Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/24/16
AREA FORECAST DISCUSSION
NWS TUCSON AZ
127 PM MST FRI APR 22 2016
.SYNOPSIS...UNSEASONABLY WARM TEMPERATURES WILL GRADUALLY DECREASE
THROUGH THE WEEKEND AS A WEAK WEATHER SYSTEM MOVES THROUGH THE AREA
TONIGHT. THIS WILL RESULT IN SLIGHTLY ABOVE NORMAL TEMPERATURES AND
BREEZY CONDITIONS. A STORM SYSTEM EARLY IN THE WEEK WILL GENERATE
GUSTY WINDS AND ANOTHER LATE IN THE WEEK WILL BRING ANOTHER ROUND OF
WINDS AND POSSIBLY A FEW SHOWERS.
&&
.DISCUSSION...
EARLY AFTERNOON SATELLITE IMAGERY REVEALS DEVELOPING CU ACROSS NEW
MEXICO...WITH EVEN A FEW DEVELOPING CLOUDS SNEAKING INTO GREENLEE
COUNTY AS OF 20Z. ASIDE FROM SOME THIN HIGH CLOUDS MOVING IN FROM
SONORA...THE REMAINDER OF THE AREA SAW CLEAR/MOSTLY CLEAR SKIES.
THIS HAS HELPED TEMPERATURES RAPIDLY RISE INTO THE LOWER 90S ACROSS
THE DESERTS.
FOR THE REST OF TONIGHT...I STILL CANNOT RULE OUT A STRAY SPRINKLE
OR SHOWER RIGHT ALONG THE AZ/NM BORDER. PAST SEVERAL RUNS OF THE UA
WRF AND THE HRRR INDICATE VERY ISOLATED COVERAGE ACROSS GREENLEE AND
EASTERN COCHISE COUNTY. I WILL HANG ONTO CLIMO-LIKE POPS IN THESE
AREAS BUT KEEP THE FORECAST DRY ELSEWHERE. MAIN THREAT WOULD BE IN
THE FORM OF DRY LIGHTNING ALTHOUGH EVEN THIS THREAT APPEARS TO BE
WANING WITH TIME.
WEAK LOW PRESSURE WILL SWEEP THROUGH THE FOUR CORNERS
TOMORROW...USHERING IN A PROLONGED PERIOD OF TROUGHING ALOFT. THIS
WILL KNOCK TEMPERATURES BACK SEVERAL DEGREES THIS WEEKEND AND WILL
ALSO BRING IN A FAIR AMOUNT OF AFTERNOON BREEZINESS. MEANWHILE A
SECONDARY LARGER TROUGH WILL MOVE THROUGH NORTHERN ARIZONA ON
TUESDAY BUT MOISTURE TRANSPORT LOOKS TO BE QUITE MEAGER AND PRECIP
CHANCES ARE ESSENTIALLY ZERO. IT WILL HOWEVER KNOCK TEMPERATURES
DOWN A BIT MORE WITH READINGS GENERALLY FORECAST TO BE 10 DEGREES
BELOW NORMAL FOR LATE APRIL. A THIRD TROUGH IS FORECAST TO ARRIVE
LATE IN THE WEEK. STILL SOME DIFFERENCES IN THE DETERMINISTIC
GUIDANCE WITH RESPECT TO EXACT TIMING AND TRAJECTORY. NAEFS
INDICATING 10-20 PERCENT CHANCES AREA-WIDE LATE NEXT WEEK AND THIS
SEEMS LIKE A MORE THAN REASONABLE STARTING POINT.
&&
.AVIATION...VALID THRU 24/00Z.
SCT TO OCCASIONALLY BKN THIN CIRRUS AOA 25K FT AGL INTO EARLY
SATURDAY WITH SKIES GENERALLY BECOMING SKC AFTER 23/18Z. SWLY WIND
10-20 KTS THIS AFTERNOON WITH GUSTS UP TO 25 KTS POSSIBLE. WINDS
WILL TAPER OFF AFTER 23/03Z BECOMING LIGHT AND TERRAIN DRIVEN THRU
23/17Z...THEN SW WINDS INCREASING AGAIN. AVIATION DISCUSSION NOT
UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...A FEW BUILDUPS THIS AFTERNOON RIGHT ALONG THE NEW
MEXICO BORDER WHERE SOME INCREASED MOISTURE HAS MOVED IN. ANY
SHOWERS OR THUNDERSTORMS THAT DEVELOP WILL MOSTLY REMAIN TO THE EAST
OF THE AREA BUT CAN`T RULE OUT SOME GUSTY WINDS AND THE POTENTIAL
FOR A DRY LIGHTNING STRIKE OR TWO WITH ANY STORMS THAT DEVELOP ALONG
THE NEW MEXICO BORDER. ANY RESIDUAL MOISTURE WILL QUICKLY BE SWEPT
BACK TO THE EAST SATURDAY AS WESTERLY FLOW INCREASES WITH A TROUGH
OF LOW PRESSURE PASSING TO THE NORTH OF THE AREA. THIS THROUGH WILL
ALSO RESULT IN SLIGHTLY COOLER TEMPERATURES AND SOME INCREASED
BREEZES BOTH SATURDAY AND SUNDAY AFTERNOON. WIND SPEEDS WILL
GENERALLY REMAIN BELOW CRITICAL THRESHOLDS...BUT WILL REMAIN CLOSE
FOR EASTERN AREAS OF COCHISE COUNTY WHERE BRIEF LOCALIZED RED FLAG
CONDITIONS ARE POSSIBLE.
ANOTHER DRY SYSTEM WILL MOVE IN PRODUCING GUSTY WINDS EARLY NEXT
WEEK WITH COOLER TEMPERATURES ESPECIALLY ON TUESDAY. THERE IS A
POTENTIAL FOR MORE WIDESPREAD CRITICAL FIRE WEATHER CONDITIONS TO BE
MET MONDAY AND TUESDAY AFTERNOON ACROSS AREAS PRIMARILY SOUTH AND
EAST OF TUCSON. THIS IS SOMETHING WE`LL BE WATCHING CLOSELY OVER THE
NEXT FEW DAYS AS WE ASSESS THE POSSIBLE NEED FOR FIRE WEATHER
HEADLINES. BREEZY AFTERNOON WINDS WILL LIKELY CONTINUE WEDNESDAY AND
THURSDAY BUT REMAIN BELOW CRITICAL LEVELS.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
853 PM PDT SAT APR 23 2016
.SYNOPSIS....DRY WEATHER IS EXPECTED ALONG WITH SEASONABLY COOL
TEMPERATURES THROUGH THE REMAINDER OF WEEKEND AND INTO EARLY NEXT
WEEK. LOCALLY STRONG AND GUSTY NORTHWEST WINDS MAY OCCUR FROM LATE
SUNDAY INTO MONDAY...MAINLY NEAR THE COAST AND LOCALLY IN THE
HILLS. THE NEXT CHANCE OF RAIN WILL BE AROUND THE MIDDLE OF NEXT
WEEK.
&&
.DISCUSSION...AS OF 8:50 PM PDT SATURDAY...PLENTY OF CUMULUS
DEVELOPED ACROSS OUR REGION THIS AFTERNOON...BUT DRY CONDITIONS
PREVAILED AND TEMPERATURES WERE A BIT WARMER THAN YESTERDAY.
EVENING IR SATELLITE IMAGERY SHOWS AN ELONGATED UPPER TROUGH
STRETCHING FROM THE GULF OF ALASKA SSE TO NEAR THE COAST OF THE
PAC NW. THE MODELS AGREE THAT THE SOUTHERN PORTION OF THIS TROUGH
WILL DIG SOUTHEAST AND INTO THE GREAT BASIN BY SUNDAY EVENING. AS
IS TYPICALLY THE CASE FOR THESE "INSIDE SLIDER" SYSTEMS...
PRECIPITATION ASSOCIATED WITH THE UPPER TROUGH WILL REMAIN TO OUR
NORTH AND EAST. THIS WEATHER SYSTEM`S PRIMARY IMPACT ON OUR
REGION`S WEATHER WILL BE TO GENERATE LOCALLY STRONG AND GUSTY
NORTHWEST WINDS BY LATE SUNDAY. STRONGEST WINDS ARE EXPECTED TO
OCCUR FROM LATE SUNDAY AFTERNOON THROUGH LATE SUNDAY EVENING WHEN
SURFACE PRESSURE GRADIENTS PEAK AND WHEN COLD ADVECTION WILL HELP
MIX STRONGER WINDS ALOFT TO THE SURFACE. DURING THIS
TIME...NORTHWEST SUSTAINED WINDS OF 20 TO 30 MPH ARE LIKELY NEAR
THE COAST...ALONG WITH GUSTS IN EXCESS OF 40 MPH. WINDS WILL BE
LOCALLY STRONG IN THE HILLS AS WELL...BUT BASED ON LATEST MODEL
OUTPUT THE STRONGEST WINDS ARE EXPECTED TO OCCUR NEAR THE OCEAN
AND THROUGH COASTAL GAPS. A WIND ADVISORY MAY BE ISSUED FOR MOST
OF OUR COASTAL ZONES FOR LATE SUNDAY AFTERNOON AND SUNDAY EVENING.
WILL WAIT FOR ALL 00Z MODEL DATA BEFORE MAKING A DETERMINATION ON
AN ADVISORY. THE 00Z NAM MOS GUIDANCE IS JUST IN AND IT SHOWS A
SLIGHT UPTICK IN WIND SPEEDS AT SFO LATE ON SUNDAY. FOR NOW HAVE
ISSUED A HAZARDOUS WEATHER OUTLOOK TO LAY THE GROUNDWORK FOR A
POSSIBLE WIND ADVISORY.
WINDS ARE FORECAST TO GRADUALLY SUBSIDE LATE SUNDAY NIGHT INTO
MONDAY MORNING...BUT THEN RAMP BACK UP AGAIN ON MONDAY AFTERNOON.
HOWEVER...WINDS ON MONDAY ARE NOT PROJECTED TO BE QUITE AS STRONG
AS ON SUNDAY EVENING.
AFTER THE WIND EVENT EARLY IN THE WEEK OUR ATTENTION WILL TURN TO
A SYSTEM THAT MAY BRING PRECIPITATION TO OUR REGION AROUND THE
MIDDLE OF NEXT WEEK. THE GFS AND ECMWF ARE IN BASIC AGREEMENT IN
BRINGING A TROUGH TO NEAR THE NORTHERN CA COAST BY LATE TUESDAY
AND THEN DIGGING THAT TROUGH TO THE SSE AND ACROSS CA ON WEDNESDAY
AND WEDNESDAY NIGHT. BASED ON THIS FORECAST TRAJECTORY...SHOWER
CHANCES WOULD BE PRETTY UNIFORM ACROSS OUR ENTIRE AREA FROM
WEDNESDAY THROUGH WEDNESDAY NIGHT. WILL ALSO NEED TO CONSIDER THE
POSSIBILITY OF THUNDERSTORMS. A FEW SHOWERS MAY LINGER INTO
THURSDAY...BUT FOR THE MOST PART DRY WEATHER IS EXPECTED FOR THE
FINAL THREE DAYS OF NEXT WEEK.
&&
.AVIATION...AS OF 5:39 PM PDT SATURDAY...DIURNAL WARMING HAS
TRIGGERED A FEW ISOLATED SHOWERS VERY RECENTLY. CLOUD BASES ARE
SEVERAL THOUSAND FEET AGL. ECHO TOPS WITH SHOWERS ARE NOT MUCH
HIGHER AT 6 TO 7 THOUSAND FEET PER KMUX RADAR. KMUX MISSING MOST
OF THIS ACTIVITY DUE TO LIMITED VERTICAL EXTENT OF CONVECTION.
CONVECTIVE CLOUDS ARE PRIMARILY STRATIFIED AS AIR PARCELS ARE FREE
TO ACCELERATE TIL REACHING THE BASE OF A SUBSIDENCE INVERSION BASED
APPROX 6 THOUSAND FEET. LOW LEVELS REMAINED COOL TODAY FURTHER DE-
STABILIZED BY DIURNAL SURFACE WARMING HOWEVER EASTWARD MOVING
MID-UPPER LEVEL SHORTWAVE RIDGE PROVIDED AIR MASS WARMING 900-300
MB LAYER TODAY COMPARING PREVIOUS 00Z SAT AND 12Z SAT OAK
SOUNDINGS. HRRR MODEL SHOWS A FEW ADDITIONAL --ISOLATED--
DIURNALLY DRIVEN SHOWERS EARLY THIS EVENING OTHERWISE REMAINING
DRY TONIGHT. OTHERWISE GOOD CHANCES FOR VFR TO PERSIST AREA-WIDE
INTO THIS EVENING.
A COLD FRONT SWEEPS SE OVER THE BAY AREA SUNDAY WITH MID LEVEL
SHORTWAVE TROUGH AMPLIFYING. EXPECT STRENGTHENING AND GUSTY W-NW
WINDS SUNDAY INTO SUNDAY NIGHT. 700-500 MB LAYER TEMP LAPSE RATES
8 C/KM TO 8.5 C/KM SUNDAY STRONGEST OVER MONTEREY AND SAN BENITO
COUNTIES BY LATE SUNDAY AFTERNOON/EVENING. MODELS FORECAST ZERO
QPF DUE TO QUITE DRY RH LAYERS THROUGHOUT VERTICAL COLUMN BUT MID
LEVEL INSTABILITY STILL PRESENT THUS DRY CONVECTION (CLOUD FREE)
POSSIBLE OR COULD SEE SOME ISOLATED VIRGA. WINDY...TURBULENT
CLASSIC MID-LATE APRIL WX SUNDAY-MONDAY.
VICINITY OF KSFO...WESTERLY WINDS 20-25 KT TIL 04Z. VFR. STRONG AND
GUSTY W-NW WINDS SUNDAY AFTERNOON/EVENING.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY TERMINALS...VFR. GUSTY W-NW WINDS THIS EVENING. GUSTY
WINDS LIKELY SUNDAY AFTERNOON AND EVENING.
&&
.MARINE...AS OF 6:36 PM PDT SATURDAY...A DRY COLD FRONT WILL
APPROACH THE NORTHERN WATERS OVERNIGHT WITH A GRADUAL INCREASE IN
NW WINDS INTO SUNDAY MORNING. BY SUNDAY AFTERNOON GALE FORCE WIND
GUSTS WILL DEVELOP OVER MOST WATERS PRODUCING ROUGH AND CHOPPY
SEAS. GALE WARNINGS CONTINUE INTO MONDAY WITH PERSISTENT NW WINDS.
WINDS WILL EASE SLIGHTLY INTO TUESDAY BUT ANOTHER UNSEASONABLY
COLD TROUGH WILL ARRIVE BY MIDWEEK WITH ANOTHER ROUND OF
WIND...SHOWERS AND DETERIORATING SEAS.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...SCA...PT ARENA TO PT REYES 0-10 NM FROM 4 AM
SCA...PT REYES TO PIGEON PT 0-10 NM FROM 4 AM
SCA...PIGEON PT TO PT PINOS 0-10 NM FROM 4 AM
SCA...PT ARENA TO PIGEON PT 10-60 NM FROM 3 AM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM FROM 3 AM
SCA...ROUGH BAR ADVISORY FOR SF BAR
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
SCA...SF BAY UNTIL 8 PM
&&
$$
PUBLIC FORECAST: DYKEMA
AVIATION: CANEPA
MARINE: CANEPA
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
559 PM PDT SAT APR 23 2016
.SYNOPSIS....DRY WEATHER IS EXPECTED ALONG WITH SEASONABLY COOL
TEMPERATURES THROUGH THIS WEEKEND AND INTO EARLY NEXT WEEK.
LOCALLY STRONG AND GUSTY NORTHWEST WINDS MAY OCCUR FROM LATE
SUNDAY INTO MONDAY...MAINLY NEAR THE COAST AND IN THE HILLS. THE
NEXT CHANCE OF RAIN WILL BE AROUND THE MIDDLE OF NEXT WEEK.
&&
.DISCUSSION...AS OF 2:13 PM PDT SATURDAY...COLD AIR ALOFT AND
DAYTIME HEATING HAS LED TO FAIR WEATHER CUMULUS DEVELOPMENT THIS
AFTERNOON. VISIBLE SATELLITE IMAGERY SHOWS CLOUDS COVERING MANY OF
THE BAY AREA HILLS. EXPECT THE CLOUD COVER TO DIMINISH THROUGH THE
DAY...MORE SO TOWARD SUNSET WITH THE LOSS OF INSOLATION. GIVEN THE
POST FRONTAL COLD ADVECTION ENVIRONMENT...BREEZY NORTHERLY FLOW
HAS ALSO BEEN OBSERVED TODAY. WIND GUSTS 15 TO 30 MPH HAVE BEEN
REPORTED.
WEAK RIDGE OF HIGH PRESSURE CURRENTLY OVERHEAD WILL WEAKEN AS AN
UPPER LEVEL LOW DROPS SOUTH INTO NORTHEAST CALIFORNIA. THE CURRENT
FORECASTED TRACK IS VERY TO AN INSIDE SLIDER. GENERALLY
SPEAKING...INSIDE SLIDERS ARE NOT RAIN PRODUCERS FOR THE BAY
AREA...BUT WIND PRODUCERS. WILL HAVE SOME CLOUDS FOR SUNDAY...BUT
NOT MENTION ANY CHANCE OF RAIN. THE BIGGER IMPACT FOR THE BAY AREA
WILL BE THE WINDS. NORTHERLY WINDS ARE FORECAST TO RAMP UP SUNDAY
AFTERNOON/EVENING. THE STRONGEST WINDS STILL APPEAR TO BE OVER THE
COASTAL WATERS...IMMEDIATE COAST AND HIGHER TERRAIN. STILL A
MARGINAL EVENT FOR A WIND ADVISORY...BUT AN OCCASIONAL GUST TO 40
MPH. WINDS SHOULD EASE IN ALL AREAS BY MONDAY AND MONDAY NIGHT.
MEDIUM RANGE MODELS ARE FINALLY COMING INTO BETTER AGREEMENT FOR
THE NEXT CHANCE OF RAIN. BY WEDNESDAY ANOTHER UPPER LOW IS
FORECAST TO DROP SOUTH...THIS TIME OVER THE BAY AREA. RAIN CHANCES
WILL INCREASE WEDNESDAY AND THURSDAY...BUT GIVEN THE UNCERTAINTY
THAT CAN ACCOMPANY UPPER LOWS THERE IS NO GUARANTEE. AS FOR
RAINFALL AMOUNTS...THEY WILL BE HEAVILY DEPENDENT UPON THE TRACK
OF THE LOW. A FEW SHOWERS LINGER THROUGH THURSDAY...BUT DRIER
WEATHER FRIDAY AND INTO THE WEEKEND.
&&
.AVIATION...AS OF 5:39 PM PDT SATURDAY...DIURNAL WARMING HAS
TRIGGERED A FEW ISOLATED SHOWERS VERY RECENTLY. CLOUD BASES ARE
SEVERAL THOUSAND FEET AGL. ECHO TOPS WITH SHOWERS ARE NOT MUCH
HIGHER AT 6 TO 7 THOUSAND FEET PER KMUX RADAR. KMUX MISSING MOST
OF THIS ACTIVITY DUE TO LIMITED VERTICAL EXTENT OF CONVECTION.
CONVECTIVE CLOUDS ARE PRIMARILY STRATIFIED AS AIR PARCELS ARE FREE
TO ACCELERATE TIL REACHING THE BASE OF A SUBSIDENCE INVERSION BASED
APPROX 6 THOUSAND FEET. LOW LEVELS REMAINED COOL TODAY FURTHER DE-
STABILIZED BY DIURNAL SURFACE WARMING HOWEVER EASTWARD MOVING
MID-UPPER LEVEL SHORTWAVE RIDGE PROVIDED AIR MASS WARMING 900-300
MB LAYER TODAY COMPARING PREVIOUS 00Z SAT AND 12Z SAT OAK
SOUNDINGS. HRRR MODEL SHOWS A FEW ADDITIONAL --ISOLATED--
DIURNALLY DRIVEN SHOWERS EARLY THIS EVENING OTHERWISE REMAINING
DRY TONIGHT. OTHERWISE GOOD CHANCES FOR VFR TO PERSIST AREA-WIDE
INTO THIS EVENING.
A COLD FRONT SWEEPS SE OVER THE BAY AREA SUNDAY WITH MID LEVEL
SHORTWAVE TROUGH AMPLIFYING. EXPECT STRENGTHENING AND GUSTY W-NW
WINDS SUNDAY INTO SUNDAY NIGHT. 700-500 MB LAYER TEMP LAPSE RATES
8 C/KM TO 8.5 C/KM SUNDAY STRONGEST OVER MONTEREY AND SAN BENITO
COUNTIES BY LATE SUNDAY AFTERNOON/EVENING. MODELS FORECAST ZERO
QPF DUE TO QUITE DRY RH LAYERS THROUGHOUT VERTICAL COLUMN BUT MID
LEVEL INSTABILITY STILL PRESENT THUS DRY CONVECTION (CLOUD FREE)
POSSIBLE OR COULD SEE SOME ISOLATED VIRGA. WINDY...TURBULENT
CLASSIC MID-LATE APRIL WX SUNDAY-MONDAY.
VICINITY OF KSFO...WESTERLY WINDS 20-25 KT TIL 04Z. VFR. STRONG AND
GUSTY W-NW WINDS SUNDAY AFTERNOON/EVENING.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY TERMINALS...VFR. GUSTY W-NW WINDS THIS EVENING. GUSTY
WINDS LIKELY SUNDAY AFTERNOON AND EVENING.
&&
.MARINE...AS OF 10:49 AM PDT SATURDAY...NORTHWEST WINDS WILL
INCREASE TODAY ACROSS THE WATERS...STRONGEST THIS AFTERNOON SOUTH
OF PT SUR. A COLD FRONT WILL SWEEP SOUTHEAST OVER THE WATERS
SUNDAY RESULTING IN INCREASING NORTHWESTERLY WINDS AND
DETERIORATING SEAS THROUGH EARLY NEXT WEEK.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...SCA...PT ARENA TO PT REYES 0-10 NM FROM 4 AM
SCA...PT REYES TO PIGEON PT 0-10 NM FROM 4 AM
SCA...PIGEON PT TO PT PINOS 0-10 NM FROM 4 AM
SCA...PT ARENA TO PIGEON PT 10-60 NM FROM 3 AM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM FROM 3 AM
SCA...ROUGH BAR ADVISORY FOR SF BAR UNTIL 6 PM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
SCA...SF BAY UNTIL 8 PM
&&
$$
PUBLIC FORECAST: MM
AVIATION: CANEPA
MARINE: R_WALBRUN
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AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
318 PM PDT FRI APR 22 2016
.SYNOPSIS...
The possibility of precipitation will end this evening, then a
high will build in over the weekend for breezy winds and a slight
warmup. a series of lows should then arrive next week for around
normal temperatures, with possible precipitation late next week.
&&
.SHORT TERM...(TDY-MON)
A weak cold front was moving into the Central Coast this afternoon,
with rainfall amounts in nwrn SLO County less than 0.10 inch along
the coast, and about 0.20 to 0.40 inch in the coastal mtns. Rocky
Butte has had 0.43 inch as the front went thru. Mostly cloudy skies
accompany the front, with mostly sunny skies over VTU/L.A. Counties
this afternoon. Onshore pressure gradients have increased to +7.7 mb
LAX-DAG and +13.6 LAX-TPH as of 21Z. These strong pressure gradients
have been driving strong and gusty sw winds thru the Antelope Vly
this afternoon, with gusts over 40 mph in a few spots. Gusts in this
area may locally reach 50 mph especially on the west side this
afternoon and evening. These winds should cause patchy blowing dust
with visibilities possibly down to one quarter mile or less at
times. A wind advisory is in effect for this area. For the mtns,
foothills, and SLO/SBA County coast and some interior vlys, s to w
winds have increased to 15 to 25 mph with gusts to 35 mph over a
large area. Temps this afternoon will top out in the 70s to around
80 for many coastal and vly areas.
An upper level trof over central and nrn CA today will move e
tonight and Sat. Weak upper level ridging will gradually move into
the area on Sat and linger Sat night. An upper level trough will
move into the area for Sun. Swrn CA will be on the srn fringes of a
broad upper level trof over e central CA into NV Sun night and Mon,
with a broad nw flow aloft over the fcst area.
The cold front is forecast to dissipate this evening with a slight
chance of showers lingering for portions of SLO/SBA Counties, and
the slight chance of showers on the n slopes later tonight.
Otherwise, partly cloudy skies overall can be expected across the
region overnight. Gusty onshore winds will prevail along the Central
Coast, foothills, mtns and deserts this evening. Winds will turn
more nw to n tonight, with gusty winds expected in the mtns along
the I-5 corridor, and the SBA County mtns and s coast. The 12Z NAM
was predicting 850 mb winds to peak around 35 KT near the I-5
corridor and SBA County mtns tonight. Advisory level winds with
gusts to 40 to 50 mph will continue tonight in the Antelope Valley,
and develop in the L.A./VTU/SBA County mtns and SBA County s coast
this evening and persist into early Sat, except thru early Sat
evening in the L.A./VTU mtns. As a result, wind advisories are also
in effect for the mtns and SBA s cst. Please see the latest non-
precipitation weather message for further details on the wind
advisories currently in effect.
There may be a few lingering clouds early Sat, otherwise
increasingly sunny skies can be expected for the bulk of the day on
Sat. Gusty nw winds are expected along the Central Coast, in the
mtns along the I-5 Corridor, and in the Antelope Vly for Sat
afternoon and evening, and in the SBA County mtns and s cst Sat
night into early Sun. Additional wind advisories may be needed in
some of these areas as well.
Partly cloudy skies at times can be expected Sat night thru Mon as
the upper trof moves in. Clouds should once again bank up on the n
mtn slopes with a slight chance of rain or snow showers later Sun
night into Mon morning. 12Z NAM boundary lyr moisture fields were
also suggesting some low clouds and fog should develop in the
Salinas River Vly later Sun night into Mon morning. Another increase
in the onshore gradients can be expected both Sun and Mon afternoon
and evening, with gusty nw winds mainly along the Central Coast, SBA
County s cst, and in the foothills, mtns and Antelope Vly. Wind
advisory level winds will be likely at times Mon afternoon and
evening in these areas, except the Central Coast may approach
advisory levels.
Temps are forecast to warm slightly back to near normal to slightly
above normal for most areas on Sat, with little change expected for
Sun and Mon.
.LONG TERM...(TUE-FRI)
The EC/GFS are in generally good agreement with the large scale
features during the period, with only minor differences by Thu and Fri.
The upper trof extending into e central CA will move well e of the
region on Tue. Upper level troffiness will move back in from the e
Pac on Wed. A cold upper level low off the central CA cst Wed will
move se and into swrn ca on Thu, then move e of the region Thu night
and Fri.
Dry weather with breezy to windy onshore flow for the afternoon and
evening hours will continue Tue thru Wed. The GFS is more robust
with the extent of the upper low off the coast Thu compared to the
EC, and the GFS is a bit wetter than the EC for Thu. There is enough
of an increase in confidence for unsettled conditions so have
increased pops to chance levels across the forecast area Wed night
and Thu. Residual moisture and upper troffiness for Thu night into
Fri has prompted a slight chance of showers to remain in the fcst to
end the work week. If the GFS verifies with the position of the
upper low on Thu, then there would be the potential for thunderstorm
development over the area with locally heavy rainfall. This
situation will be closely monitored over the next several model
runs, but since this potential weather event is still six days away,
will not add the mention of thunderstorms just yet.
Temps will be generally near normal or slightly below normal Tue and
Wed, cool to several deg below normal for Thu, then warm slightly
Fri but still remain slightly below normal overall.
&&
.AVIATION...22/1800Z...
Mid/upper level trough of low pressure over Northern California
will shift east while a mid/upper level ridge of high pressure
over the Eastern Pacific moves over the area. Upper level
strong northwest winds will become moderate west-northwest after
23/22z and mid level moderate west winds will become moderate
northwest after 23/07z. Surface trough of low pressure and low
cloud field approaching the Central Coast will dissipate and mix
out today. Weak to moderate onshore pressure gradient will become
moderate northerly gradient between 23/05-23/17z then mixed
moderate onshore and moderate northerly gradient thereafter.
Marine inversion base was unorganized and varied from near the
surface and 5kft along the central coast to 1.7kft over KLAX this
morning with a scattered cloud field. The inversion is expected to
mix out today and not redevelop Saturday morning.
Marine layer at LAX at 1600Z is 1688 feet deep and the inversion
top is at 5431 feet with a temp of 12.1 degrees C.
KLAX...Few low clouds will dissipate through 22/19z then it is very
likely no low/mid level cigs and/or vsby below 6sm through the
period.
KBUR...Very likely current sky/vsby conditions will prevail.
virtually certain - 95-100%
very likely - 80-95%
likely - 60-80%
chance - 30-60%
very unlikely - 20% OR LESS
&&
.MARINE...22/200 pM...
There is a chance small craft advisory conditions will exist in
the vicinity of the Northern Channel Islands to San Mateo Point this
afternoon through this evening. Northwest winds will likely
increase Saturday in the vicinity of the Channel Islands and over
the entire area Sunday and there is a chance gale force winds will
exist Saturday afternoon in the vicinity of the Channel Islands
and over the entire area at times Sunday afternoon through Monday
night. Otherwise seas currently in the Eastern Pacific and
oriented 290-310 degrees relative to Ventura coast will arrive
through Saturday morning and there is a chance small craft
advisory for hazardous sea conditions will exist from Piedras
Blancas to San Clemente Island Saturday through Sunday morning. A
storm force wind fetch is expected to develop in the Southern
Ocean and oriented 190-180 degrees to Ventura County Saturday.The swells
that will begin to arrive next week Saturday and probably
generate hazardous surf and extra currents and surging along
exposed south facing shores Saturday night through Monday.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory in effect from 8 PM this evening to 8 AM PDT
Saturday For zones 39-52. (See LAXNPWLOX).
Wind Advisory in effect from 8 PM this evening to 8 PM PDT
Saturday For zones 53-54. (See LAXNPWLOX).
Wind Advisory in effect until 8 AM PDT Saturday For zone 59. (See LAXNPWLOX).
PZ...Gale Watch in effect from Sunday afternoon through late
Monday night For zones 645-670-673-676. (See LAXMWWLOX).
Small Craft Advisory in effect until 1 AM PDT Saturday For
zones 650-655. (See LAXMWWLOX).
Gale Watch in effect from Sunday evening through Monday
evening For zones 650-655. (See LAXMWWLOX).
Small Craft Advisory in effect until 3 PM PDT Sunday For
zones 670-673-676. (See LAXMWWLOX).
&&
$$
PUBLIC...Sirard
AVIATION...30
MARINE...30
SYNOPSIS...Seto
weather.gov/losangeles
Area Forecast Discussion
National Weather Service Reno NV
303 PM PDT FRI APR 22 2016
.SYNOPSIS...
A strong Pacific storm will continue to move through the Sierra
and Western Nevada tonight. Rain and heavy mountain snow are
expected this evening near and south of I-80. A break is expected
Saturday before more showers are expected Sunday into Monday with
another system. Unsettled weather will continue through next week
with below average temperatures.
&&
.SHORT TERM...
A strong spring storm continues to move through. Heavy snow is
falling in the Sierra with rates approaching 3"/hr. It is best to
avoid travel in the Sierra for the next few hours if possible.
Heavy convective snowfall continues in the Sierra with the bands
extending from Westwood south into Bridgeport. Heavy snow is
falling above 6000 feet, with the snow level locally down to 4500
feet in the heaviest bands. Latest satellite/radar trends support
the HRRR in keeping the heaviest rain/snow going thru 03Z near and
south of I-80. After there will be a rapid reduction in showers as
the upper forcing moves east and the airmass stabilizes.
Until then, another 6+ inches of snow is possible above 7000 feet
with another 2-4" down to 5500-6000 feet. Rainfall into Western NV
will be heaviest in the Sierra front where an additional 1/4" of
rain is possible. It may mix with snow at times in the foothills
while lighter amounts are expected toward the highway 95 corridor.
Winds are much weaker along the Sierra Front with the precip
falling, but strong gusts continue east of a Bridgeport to
Lovelock line. Will cancel the advisory for Reno-Carson-Minden,
but leave the remainder as the winds continue there.
Behind this storm, a break is expected Saturday with continued
cool temps, but lighter winds and dry conditions. Another upper
low is expected Sunday afternoon into Monday. Showers are expected
Sunday afternoon with enough instability for a few thunderstorms
as well. The core of the low will move overhead Monday morning
with much colder air. Snow levels will fall to near the valley
floors. While this storm will have some moisture with it, the best
forcing is expected to remain over Eastern NV so we are not
expecting another big precip event. However, there remains a
threat (low at this time) of some light snowfall during the Monday
morning commute along the I-80 and highway 50 corridors. Wallmann
.LONG TERM...Monday Night through Friday...
Unsettled weather pattern is expected to continue through next
week as late season storm systems line up to move into the West
Coast. Wednesday-Friday could be a rather wet period for much of
the region with potential for additional snow in higher
elevations.
For Monday night, the first upper low is likely to be on its way
out with lingering rain and snow showers diminishing. Tuesday
still looks like the least active weather day, although a few
showers remain possible as residual moisture will remain in place.
Even though temperatures are expected to increase about 10-15
degrees from Monday, highs in the lower 60s and around 50 degrees
near the Sierra will still be a few degrees below average for late
April.
For next Wednesday-Friday, medium range guidance continues to
indicate a potent low pressure tracking southward along the
California coast, then swing inland across the southwest US (or
possibly farther north into eastern NV). Despite this southerly
track, a broad area of upper divergence and instability is
projected to set up over the Sierra and western NV, along with a
decent tap of Pacific moisture. A few thunderstorms are also
possible each afternoon, although the better instability looks to
be trending north of I-80 by next Friday. Current projections
favor the best overall rain and snow chances Wednesday night and
higher thunderstorm potential on Thursday, but this could vary
depending on the eventual storm track. Widespread cloud cover will
keep daytime temps a few degrees below average each day, with
nighttime temps slightly above average. Early snow level
projections generally range from 6000-7000 feet in the Sierra,
although these snow levels could occasionally drop several hundred
feet during convection or heavier precip bands. MJD
&&
.AVIATION...
The most significant weather effects on aviation will continue
through this evening with IFR/LIFR cigs/vsby in snow near the
Sierra including KTVL/KTRK/KMMH, and a few inches of snow
accumulating on pavement. For lower elevations including KRNO-
KCXP, rain will produce MVFR cigs/vsby with mountain obscurations,
IFR at times during heavier rain bands. The strongest winds have
ended at KRNO-KCXP but some gusts to 35 KT remain possible. KMMH
may receive stronger gusts above 40 KT until 03z.
Later tonight, if cloud cover breaks up sufficiently, areas of
FZFG would develop across many Sierra valleys around Tahoe and
northeast CA, including KTRK. For Saturday, generally VFR
conditions are expected with lighter winds. MJD
&&
.REV Watches/Warnings/Advisories...
NV...Winter Weather Advisory until 11 PM PDT this evening NVZ002.
Wind Advisory until 8 PM PDT this evening NVZ001-004.
CA...Winter Weather Advisory until 5 PM PDT this afternoon above 5500
feet in CAZ071.
Wind Advisory until 8 PM PDT this evening CAZ073.
Winter Weather Advisory until 11 PM PDT this evening CAZ072.
&&
$$
For more information from the National Weather Service visit...
http://weather.gov/reno
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
230 PM PDT FRI APR 22 2016
.SYNOPSIS....A FEW SHOWERS WILL LINGER INTO THE EVENING HOURS
BEFORE DRIER CONDITIONS DEVELOP TONIGHT. DRY WEATHER IS EXPECTED
ALONG WITH SEASONABLY COOL TEMPERATURES THIS WEEKEND. A LOW
PRESSURE SYSTEM DROPPING INTO THE INTERIOR WILL BRING A SLIGHT
CHANCE OF SHOWERS FOR THE MIDDLE OF NEXT WEEK.
&&
.DISCUSSION...AS OF 02:50 PM PDT FRIDAY...IN THE NEAR TERM ACTIVE
WEATHER CONTINUES AS A COLD FRONT CONTINUES TO THE MOVE THROUGH
THE REGION. THE FRONTAL PASSAGE THIS AFTERNOON BROUGHT MODERATE TO
LOCALLY HEAVY RAIN SHOWERS TO PORTION OF THE BAY AREA. THERE ARE
SOME DECENT SIX HOUR RAINFALL TOTALS...OVER ONE INCH NEAR PALO
ALTO AND SAN MATEO. OTHER HIGH SPOTS INCLUDE PORTIONS OF THE BIG
SUR COAST...UP TO ONE INCH AND MANY OTHER LOCATIONS ONE HALF INCH
TO THREE QUARTERS OF AN INCH. NOT A DROUGHT BUSTER...BUT MUCH
NEEDED RAINFALL NON THE LESS. THERE WAS EVEN ONE REPORT OF SMALL
HAIL NEAR HEALDSBURG.
THIS AFTERNOON INTO THIS EVENING...SHOWERS WILL STILL BE POSSIBLE
WITH THE GREATEST LIKELIHOOD FROM SAN JOSE SOUTH. HAVE NOT
RECEIVED ANY REPORTS OF THUNDER OR NOTICED LIGHTNING ON THE
DETECTION NETWORK...BUT GIVEN DAYTIME HEATING AND UNSTABLE
AIRMASS WILL KEEP THE MENTION OF THUNDERSTORMS THROUGH LATE THIS
AFTERNOON. BY LATE THIS EVENING...EXPECT PRECIP CHANCES TO
DIMINISH RATHER QUICKLY...ESPECIALLY POST SUNSET. LATEST HRRR
MODEL CONCURS AND SHOWS LITTLE IN THE WAY OF PRECIP AFTER 03Z.
FOR THE UPCOMING WEEKEND...DRY CONDITIONS DEVELOP AS RIDGING
OCCURS OVER THE REGION. THE RIDGE WEAKENS BY SUNDAY AS ANOTHER
LOW PRESSURE MOVES INTO INTERIOR CALIFORNIA. ANY RAIN LOOKS TO
REMAIN NORTH AND EAST OF THE BAY AREA AT THIS TIME. HOWEVER...ONE
IMPACT FOR THE BAY AREA WILL BE THE WINDS. NORTHERLY WINDS WILL
INCREASE 15 TO 25 MPH WITH STRONGER GUSTS OVER 30 MPH. AT THIS
TIME IT IS BORDERLINE FOR A WIND ADVISORY.
THE 12Z MODEL GUIDANCE STILL SHOWS LOTS OF UNCERTAINTY FOR THE
MIDDLE OF NEXT WEEK REGARDING RAIN CHANCES. MEDIUM RANGE MODELS
STILL INDICATE A SPREAD IN SOLUTIONS...BUT AT LEAST THEY ALL SHOW
A LOW PRESSURE SYSTEM MOVING OVER THE REGION. THE DETAILS ON THE
THE OTHER HAND VARY. GIVEN THE LOW CONFIDENCE WILL CONTINUE WITH A
SLIGHT CHANCE FOR SHOWERS.
&&
.AVIATION...AS OF 10:45 AM PDT FRIDAY...CURRENTLY TRYING TO TIME
THE RAIN ACROSS THE VARIOUS TERMINALS. EARLY RUNS OF THE HRRR DID
NOT INITIALIZE WELL SO USING IT WITH SOME CAUTION FOR THE LATEST
PACKAGE. IN GENERAL LOOK FOR MVFR TO VFR CIGS WITH RAIN SHUTTING
OFF NORTH TO SOUTH STARTING AROUND 0Z...OR POSSIBLY A BIT EARLIER.
WILL BE KEEPING A CLOSE EYE ON RADAR AND LIGHTNING PRODUCT AS
HEATING DURING THE DAY COULD TRIGGER A FEW THUNDERSTORMS. WINDS
FORECAST TO BECOME MORE 260 TO 290 LATER IN THE DAY BEHIND THE
COLD FRONT. RETURN TO VFR FOR TOMORROW. MODERATE CONFIDENCE.
VICINITY OF KSFO...-SHRA EXPECTED AT LAST THROUGH 0Z AND POSSIBLY
AN HOUR OR TWO LONGER. CIGS GENERALLY WILL STAY AT OR ABOVE 030
THROUGH THE PERIOD. WINDS FROM 220 TO 240 WILL REMAIN OVER 20 KT
WITH OCCASIONAL GUSTS TO 30 KT. WINDS AROUND 220 BECOME MORE 260
TO 280 AROUND 02Z. IMPROVING CONDITIONS AFTER 09Z WITH VFR
FORECAST FOR TOMORROW. MODERATE CONFIDENCE.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY TERMINALS...-SHRA FORECAST TO RETURN AROUND 19Z WITH
POTENTIAL FOR SHRA OR EVEN +SHRA ALONG WITH MVFR CIGS. SHOWERS
END AFTER 03Z WITH VFR FORECAST BEYOND THAT POINT. WINDS FORECAST
TO BECOME MORE 230 TO 260 WITH SPEEDS OVER 12 KT LATER IN THE
AFTERNOON. MODERATE CONFIDENCE.
&&
.MARINE...AS OF 01:57 PM PDT FRIDAY...NORTHWESTERLY WINDS BEHIND A
DEPARTING COLD FRONT WILL SLOWLY DIMINISH TONIGHT. A SECOND COLD
FRONT WILL DROP THROUGH THE WATERS WITH INCREASING NW WIND AND
SEAS SUNDAY THROUGH EARLY NEXT WEEK. GALE FORCE WINDS ARE POSSIBLE
FOR SUNDAY NIGHT IN OUR OUTER WATERS.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...SCA...SF BAY UNTIL 9 PM
SCA...PT ARENA TO PT REYES 0-10 NM UNTIL 9 PM
SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 9 PM
SCA...PT ARENA TO PIGEON PT 10-60 NM UNTIL 9 PM
&&
$$
PUBLIC FORECAST: MM
AVIATION: BELL
MARINE: BELL
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
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WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1050 AM PDT FRI APR 22 2016
.SYNOPSIS....A COLD FRONT WILL SLIDE ACROSS THE FORECAST AREA
TODAY BRINGING THE POSSIBILITY OF A WET MORNING COMMUTE FOR THE
SAN FRANCISCO BAY AREA. SHOWERS WILL LINGER INTO THE EVENING HOURS
WITH A SLIGHT CHANCE OF AFTERNOON THUNDERSTORMS. THE BEST
POSSIBILITY OF THUNDERSTORMS WILL BE FROM SAN JOSE NORTHWARD.
DRY WEATHER IS EXPECTED ALONG WITH SEASONABLY COOL TEMPERATURES
THIS WEEKEND. A LOW PRESSURE SYSTEM DROPPING INTO THE INTERIOR
WILL BRING A SLIGHT CHANCE OF SHOWERS FOR THE MIDDLE OF NEXT WEEK.
&&
.DISCUSSION...AS OF 09:29 AM PDT FRIDAY...MAIN FOCUS TODAY WILL
BE IN THE NEAR TERM AND LATE THIS AFTERNOON. CURRENT SITUATION HAS
A COLD FRONT MOVING THROUGH THE BAY AREA AS OF THIS WRITING. THE
FRONTAL BOUNDARY HAS BROUGHT WIDESPREAD PRECIP TO THE BAY
AREA...SOME OF IT MODERATE TO LOCALLY HEAVY AT TIMES. A PUBLIC
INFORMATION STATEMENT HAS BEEN ISSUED WITH RAINFALL TOTALS. SINCE
LAST NIGHT...RAIN WAS HEAVIEST OVER THE NORTH BAY WITH OVER ONE
INCH AT MT SAINT HELENA. OTHER NOTABLE AMOUNTS ACROSS THE NORTH
BAY WERE GENERALLY IN THE ONE HALF INCH TO THREE QUARTERS OF A
INCH. LOCATIONS SOUTH OF THE GOLDEN GATE WERE GENERALLY LESS AND A
FEW TENTHS TO A LITTLE OVER ONE HALF INCH. LATEST KMUX IMAGERY
CONTINUES TO SHOW RADAR ECHOES ACROSS THE BAY AREA WITH A FEW
EMBEDDED MODERATE TO HEAVY SHOWERS. PER THE NEARBY
PROFILERS...FREEZING LEVELS ARE 4500-5000 FEET. THE STRONGER CELLS
MAY INCLUDE SMALL HAIL.
AS THE FRONT CONTINUES TO MOVE SOUTH PRECIP COVERAGE WILL
GRADUALLY DIMINISH. HOWEVER...LATEST MODELS CONTINUE TO INDICATE
A SECOND ROUND OF SHOWERS POSSIBLE THIS AFTERNOON. IN FACT...THERE
WILL BE A GREATER LIKELIHOOD FOR THUNDERSTORMS THIS
AFTERNOON...MAINLY NORTH OF SAN JOSE. DAYTIME HEATING WITH COLD
AIR ALOFT WILL LEAD TO AN UNSTABLE AIRMASS. WILL HAVE TO KEEP AN
EYE ON THE RADAR WITH POSSIBLE THUNDERSTORMS.
NO UPDATE IS PLANNED AT THIS TIME...BUT WILL BE MONITORING THE
CURRENT WEATHER SITUATION AND ADJUSTING AS NEEDED.
&&
.PREV DISCUSSION...AS OF 2:55 AM PDT FRIDAY...A WEAK RIDGE OF
HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT TONIGHT INTO SATURDAY
PROVIDING DRY WEATHER THROUGH AT LEAST SATURDAY. THE RIDGE BREAKS
DOWN SUNDAY AS A STORM SYSTEM PUSHES INTO THE PACIFIC NORTHWEST
WHICH WILL HELP TO MAINTAIN COOL DAYTIME TEMPERATURES THROUGH
MONDAY. FORECAST CONFIDENCE BEGINS TO DIMINISH MIDWEEK AS THE
FORECAST MODELS MOVE ANOTHER LOW PRESSURE SYSTEM THROUGH THE AREA
WHICH MAY PROMOTE A POSSIBILITY OF SHOWERS ON WEDNESDAY AND
THURSDAY...POSSIBLY EVEN NEXT FRIDAY.
&&
.AVIATION...AS OF 10:45 AM PDT FRIDAY...CURRENTLY TRYING TO TIME
THE RAIN ACROSS THE VARIOUS TERMINALS. EARLY RUNS OF THE HRRR DID
NOT INITIALIZE WELL SO USING IT WITH SOME CAUTION FOR THE LATEST
PACKAGE. IN GENERAL LOOK FOR MVFR TO VFR CIGS WITH RAIN SHUTTING
OFF NORTH TO SOUTH STARTING AROUND 0Z...OR POSSIBLY A BIT EARLIER.
WILL BE KEEPING A CLOSE EYE ON RADAR AND LIGHTNING PRODUCT AS
HEATING DURING THE DAY COULD TRIGGER A FEW THUNDERSTORMS. WINDS
FORECAST TO BECOME MORE 260 TO 290 LATER IN THE DAY BEHIND THE
COLD FRONT. RETURN TO VFR FOR TOMORROW. MODERATE CONFIDENCE.
VICINITY OF KSFO...-SHRA EXPECTED AT LAST THROUGH 0Z AND POSSIBLY
AN HOUR OR TWO LONGER. CIGS GENERALLY WILL STAY AT OR ABOVE 030
THROUGH THE PERIOD. WINDS FROM 220 TO 240 WILL REMAIN OVER 20 KT
WITH OCCASIONAL GUSTS TO 30 KT. WINDS AROUND 220 BECOME MORE 260
TO 280 AROUND 02Z. IMPROVING CONDITIONS AFTER 09Z WITH VFR
FORECAST FOR TOMORROW. MODERATE CONFIDENCE.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY TERMINALS...-SHRA FORECAST TO RETURN AROUND 19Z WITH
POTENTIAL FOR SHRA OR EVEN +SHRA ALONG WITH MVFR CIGS. SHOWERS
END AFTER 03Z WITH VFR FORECAST BEYOND THAT POINT. WINDS FORECAST
TO BECOME MORE 230 TO 260 WITH SPEEDS OVER 12 KT LATER IN THE
AFTERNOON. MODERATE CONFIDENCE.
&&
.MARINE...AS OF 10:45 AM PDT FRIDAY...SOUTH TO SOUTHWESTERLY
WINDS WILL CONTINUE TO SLIGHTLY INCREASE TODAY AS A COLD FRONT
MOVES TOWARD OUR REGION. WINDS WILL BECOME NORTHWEST LATER TODAY
INTO TONIGHT BEHIND THE DEPARTING FRONT. A DRY COLD FRONT WILL
DROP THROUGH THE WATERS WITH INCREASING NW WIND AND SEAS SUNDAY
THROUGH EARLY NEXT WEEK.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...PT ARENA TO PIGEON PT 10-60 NM UNTIL 3 PM
&&
$$
PUBLIC FORECAST: MM
AVIATION: BELL
MARINE: BELL
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
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AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
241 AM PDT FRI APR 22 2016
.SYNOPSIS...
A LOW PRESSURE TROUGH WILL MOVE THROUGH NORTHERN CALIFORNIA TODAY
AND TONIGHT. IT WILL BRING COOLER WEATHER, MORE CLOUDS, STRONG
WINDS IN THE MOUNTAINS AND DESERTS, AS WELL AS A SLIGHT CHANCE OF
LIGHT SHOWERS TONIGHT. THE WEEKEND WILL CONTINUE RELATIVELY COOL,
BUT SEASONAL. ON SUNDAY NIGHT AND MONDAY ANOTHER TROUGH OF LOW
PRESSURE WILL MOVE THROUGH CALIFORNIA AND BRING A SMALL CHANCE OF
SHOWERS AND GUSTY WINDS. ANOTHER POSSIBILITY OF RAIN ARRIVES
THURSDAY.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
LOW CLOUDS ARE TRYING TO FORM, BUT ARE STRUGGLING SOMEWHAT TO GAIN
MUCH TRACTION THIS MORNING. PARTLY CLOUDY SKIES WILL PREVAIL TODAY
AND IT WILL BE MUCH COOLER. A TROUGH OF LOW PRESSURE WILL MOVE
THROUGH NORTHERN CALIFORNIA TODAY AND TONIGHT. IT WILL BRING US MORE
CLOUDS TONIGHT LEADING TO VERY ISOLATED LIGHT SHOWERS WEST OF THE
MOUNTAINS. STRONG WINDS WILL BE A BIGGER PLAYER FOR THE MOUNTAINS
AND DESERTS. TOP GUSTS IN THE LEE OF MOUNTAINS AND GAPS WILL
EXCEED 55 MPH, SO A WIND ADVISORY IS IN PLACE. THIS TROUGH MOVES
OUT SATURDAY, BUT NOT A LOT OF HIGH PRESSURE FOLLOWS SO THE
WEEKEND WILL STAY FAIRLY COOL. THE NEXT TROUGH TRACKS DOWN THE
COAST AND THROUGH CALIFORNIA SUNDAY NIGHT AND MONDAY. THIS HAS
MORE COLD AIR AND ENERGY, BUT LACKS IN MOISTURE. THE CHANCE OF
SHOWERS IS SMALL, BUT THERE WILL BE STRONG WINDS AGAIN IN THE
MOUNTAINS AND DESERTS. TUESDAY AND WEDNESDAY LOOK FAIR AND
SEASONAL BEFORE THE NEXT, THIRD TROUGH ARRIVES THURSDAY.
CONFIDENCE IS LOWER ABOUT THE TIMING AND INTENSITY OF THIS SYSTEM,
BUT SMALL CHANCES ARE IN THE FORECAST. THE COMING WEEK LOOKS
SEASONAL FOR TEMPERATURES WITH A FEW EPISODES OF GUSTY WINDS AND A
FEW SHOWERS.
&&
.AVIATION...
220930Z...COAST/VALLEYS...AREAS OF LOW CLOUDS NEAR THE COAST WITH
BASES 700-1200 FT MSL SPREADING ABOUT 10 SM INLAND THROUGH 15Z
TODAY. LOCAL VIS 3-5 MI IN FOG ON THE MESAS AND IN THE VALLEYS.
BASES RISING A FEW HUNDRED FEET AFTER 12Z. LOW CLOUDS AND FOG
DISSIPATING BY MID-MORNING. BKN-OVC CIGS RETURNING TO COASTAL TAF
SITES AFTER 02Z SAT WITH BASES AROUND 2000 FT.
MOUNTAINS/DESERTS...INCREASING WEST WINDS TODAY WITH SURFACE GUSTS
30-40 KT POSSIBLE AFTER 18Z WILL PRODUCE MODERATE UP/DOWN DRAFTS
AND LLWS OVER AND EAST OF THE MOUNTAINS.
&&
.MARINE...
230 AM...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH THIS
MORNING. GUSTY NORTHWEST WINDS OF 15-20 KT THIS AFTERNOON THROUGH
SATURDAY NIGHT WITH GUSTS FROM 20-25 KT AS A LOW PRESSURE TROUGH
MOVES THROUGH CENTRAL CA. CONTINUED BREEZY SATURDAY.
SUNDAY THROUGH TUESDAY MORNING, A LARGE NORTHWEST SWELL OF 9-12 FEET
AT 9-11 SECONDS FROM 290 DEGREES WILL MOVE INTO THE COASTAL WATERS.
THIS WILL COMBINE WITH STRONGER NORTHWEST WINDS THAT GUSTING 25-30
KT AS A SECOND TROUGH OF LOW PRESSURE MOVES ACROSS THE REGION. THE
STRONG WINDS AND NORTHWEST SWELL WILL CREATE COMBINED SEAS OF 9 TO
12 FEET, RESULTING IN CONDITIONS HAZARDOUS TO SMALL CRAFT. A SMALL
CRAFT ADVISORY WILL BE IN EFFECT FRIDAY AFTERNOON THROUGH TUESDAY
MORNING.
&&
.BEACHES...
230 AM...WAVE MODELS INDICATE A NW SWELL OF 10-13 FT AT ABOUT 9
SECONDS WILL MOVE INTO THE SOUTHERN CA BIGHT MON AND TUE. THIS SWELL
COULD RESULT IN ELEVATED SURF OF AROUND 6 FT WITH HIGHER SETS ON
EXPOSED WEST-FACING BEACHES...ALONG WITH STRONG RIP CURRENTS.
A LARGE NORTHWEST SWELL FROM 290 DEGREES WILL RESULT IN
ELEVATED SURF OF 3 TO 6 FEET WITH HIGHER SETS POSSIBLE. STRONG RIP
CURRENTS TUESDAY.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...WIND ADVISORY FROM 5 PM THIS AFTERNOON TO 5 AM PDT SATURDAY FOR
APPLE AND LUCERNE VALLEYS-COACHELLA VALLEY-RIVERSIDE COUNTY
MOUNTAINS-SAN BERNARDINO COUNTY MOUNTAINS-SAN DIEGO COUNTY
DESERTS-SAN DIEGO COUNTY MOUNTAINS-SAN GORGONIO PASS NEAR
BANNING.
PZ...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 11 AM PDT
TUESDAY FOR COASTAL WATERS FROM SAN MATEO POINT TO THE
MEXICAN BORDER AND OUT TO 30 NM-WATERS FROM SAN MATEO POINT
TO THE MEXICAN BORDER EXTENDING 30 TO 60 NM OUT INCLUDING
SAN CLEMENTE ISLAND.
&&
$$
PUBLIC...MM
AVIATION/MARINE/BEACHES...PG
Area Forecast Discussion
National Weather Service Reno NV
238 AM PDT FRI APR 22 2016
SYNOPSIS...
A potent Pacific storm will move through the region today. Strong
and gusty winds can be expected along with valley rain and
mountain snow. A brief break is expected Saturday before a series
of systems is expected next week. Showery conditions are expected
Sunday afternoon and beyond along with cool temperatures.
&&
.SHORT TERM...
Moderate spring storm (by Sierra standards) with a strong cold
front is currently moving on shore and will impact the Sierra and
western Nevada today. No major changes were made to the forecast
with all winter weather and wind advisories still on track today.
Travel over Sierra passes today will very likely be impacted by
winter driving conditions so plan accordingly.
Current radar shows the leading edge of the strong cold front
currently moving into northern California. Instability ahead of
the front is currently creating some convective showers along the
Sierra crest around Donner Summit with off and on light showers
remaining possible until the cold front arrives. Precipitation may
start out as rain but is expected to change over to snow
relatively quickly above 7000 feet. HRRR model solutions show the
leading edge of the main cold front and heavy precipitation will
impact the Sierra around 10-11 am today with passes in the
northern Sierra (Yuba and Fredonyer) receiving heavy precipitation
as early as 7-8 am. For more details on snow amounts and timing
see the winter weather advisories.
Precipitation is expected to quickly spill into the lee of the
Sierra due to very unstable environment along the cold front and
strong upper level jet support. This will lead to periods of
brief moderate precipitation in western Nevada valleys. The
convective nature of this system will lead to wide disparities in
rain and snow amounts from one place to another depending on where
convective bands set up. There will also be the chance for a few
isolated thunderstorms today as the front quickly moves into
western Nevada.
Winds are expected to be quite strong today in western Nevada as
surface gradients tighten and instability will allow strong 700
mb winds to mix to the surface. Widespread winds of 25-35 mph
should be expected with peaks gusts of 50 mph and up to 60 mph in
wind prone areas. This could create some localized areas of
blowing dust which even if brief can cause hazardous driving
conditions.
This system is quite progressive with the cold front expected to
move into Utah by late Friday night. A few showers may linger
along the Sierra crest but the precipitation should be over by
Saturday morning. Brief shortwave ridging on Saturday will be
replaced by another trough digging into the area on Sunday. This
could bring another round of cold air and precipitation on Sunday
into Monday. Zach
.LONG TERM...Monday through Thursday...
Unsettled weather pattern is expected to continue through next week
as late season storm systems line up to move into the West Coast.
There is good agreement in the models that cold low pressure will
remain over the Great Basin on Monday with additional showers and
convective precipitation bands due to unstable conditions.
There is a possibility that we could see snow levels dropping to
near 4500 feet on Monday morning as the coldest air is expected to
move over the Sierra and western NV. Forecast confidence on seeing
snow to the valley floors is low, although there is a chance we
could see light slushy accumulations in the valleys and foothills of
western NV. Models have trended further east into central and
northeastern NV with the heaviest bands, but we will need to keep a
close eye on how this evolves over the next couple days as it has
potential to affect the Monday morning commute. High temperatures on
Monday will struggle to get out of the 40s in western NV and 30s in
the Sierra due to the low pressure overhead and abundant cloud
cover/showers. Low pressure will move out of the area Tuesday with
warming temperatures and clearing skies.
By Wednesday, another low pressure system is expected to move
into northern CA/NV bringing additional chances for showers and
increasing clouds. There is much uncertainty for the Wednesday-
Thursday timeframe regarding precipitation amounts, although this
system doesn`t look to be quite as cold as the the Monday system.
Hoon
&&
.AVIATION...
Multiple weather-related impacts to aviation are expected through
tonight as potent low pressure moves across the region.
Winds will be the primary impact today with wind shear potential,
mainly at KRNO-KCXP-KMMH as winds above the surface increase.
Widespread turbulent conditions are likely through today with peak
gusts up to 45 kt in the lower elevations and Sierra ridge gusts
near 80 kt.
Rain and snow will reach the northern Sierra early this morning,
then spread into western Nevada by this afternoon. Snow levels
should fall to 6000-7000 feet by this afternoon, which may bring IFR
conditions to KTRK, KTVL and KMMH. Snow accumulations on paved
surfaces are unlikely during the day, but some light accumulations
up to 2 inches are possible with the back edge of the snow moving
through this evening. For the western Nevada terminals including
KRNO and KCXP, precipitation will be all rain with reduced ceilings
for MVFR conditions this afternoon-evening. MJD/Hoon
&&
.REV Watches/Warnings/Advisories...
NV...Lake Wind Advisory until 8 AM PDT this morning for Lake Tahoe in
NVZ002.
Winter Weather Advisory from 8 AM this morning to 11 PM PDT this
evening NVZ002.
Wind Advisory from 11 AM this morning to 8 PM PDT this evening
NVZ001-004.
Wind Advisory until 5 PM PDT this afternoon NVZ003.
CA...Winter Weather Advisory from 5 AM early this morning to 5 PM PDT
this afternoon above 5500 feet in CAZ071.
Wind Advisory from 5 AM early this morning to 8 PM PDT this
evening CAZ073.
Lake Wind Advisory until 8 AM PDT this morning for Lake Tahoe in
CAZ072.
Winter Weather Advisory from 8 AM this morning to 11 PM PDT this
evening CAZ072.
&&
$$
For more information from the National Weather Service visit...
http://weather.gov/reno
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
956 PM MDT SAT APR 23 2016
.UPDATE...
ISSUED AT 838 PM MDT SAT APR 23 2016
MAIN FRONT HAS PUSHED THROUGH THE AREA WITH SHOWERS AND
THUNDERSTORMS DIMINISHING WEST TO EAST...WITH SOME ACTIVITY
REMAINING OVER THE FAR NORTHEASTERN PLAINS. A DRY SLOT NOTED ON
WATER VAPOR SATELLITE OVER CENTRAL COLORADO WILL KEEP THE REST OF
THE EVENING MAINLY DRY BEFORE WRAPAROUND MOISTURE AROUND THE
WYOMING UPPER LOW WILL PUSH SNOW BACK INTO THE NORTHERN MOUNTAINS.
HAVE UPDATED TONIGHTS WEATHER GRIDS TO REFLECT THESE TRENDS. STILL
EXPECTING THE WINDS TO CONTINUE IN THE HIGH COUNTRY AND FOOTHILLS
OVERNIGHT...INCREASING TOWARD MORNING.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 233 PM MDT SAT APR 23 2016
THE UPPER TROUGH OVER NORTHERN UTAH/SOUTHWESTERN WYOMING THIS
AFTERNOON WILL TRACK TO THE NORTHEAST INTO CENTRAL WYOMING
OVERNIGHT...THEN INTO SOUTH DAKOTA BY LATE AFTN. BEST QG ASCENT
ASSOCIATED WITH THIS PASSING TROUGH WILL AROUND 00Z THEN STRONGER
QG DESCENT BUILDS IN FROM THE WEST. THE LATEST HRRR DEVELOPS A
LITTLE BETTER SHOWER/TSTMS COVERAGE BUT IT LOOKS OVERDONE COMPARED
TO PRVS RUNS. BEST CHC FOR MOUNTAIN SNOW WILL BE IN ZONES 31 AND
33...WITH BEST SHOWER/TSTM POTENTIAL ALONG THE NORTHEAST BORDER
OF THE NORTHEAST PLAINS. SHOWERS/TSTMS LATE THIS AFTN AND EVENING
COULD PACK SOME FAIRLY STRONG GUSTS...UP TO 50 MPH ACROSS THE
NORTHEAST PLAINS. STRONG JETSTREAM WINDS ALOFT OVER THE CWA THIS
AFTN SO EVEN STRONGER GUSTS IN THE MOUNTAINS/HIGHER FOOTHILLS TO
70 MPH. STRONG SUBSIDENCE LATER THIS EVENING WILL PRODUCE
AN AMPLIFIED MOUNTAIN WAVE SO STRONGER GUSTS WILL PERSIST ACROSS
THOSE AREAS OVERNIGHT. STRONGER WINDS ACROSS THE NORTHEAST PLAINS
SHOULD SUBSIDE AFT 03Z WITH THE DISSIPATION OF ANY SHOWERS. ON
SUNDAY...MDLS STILL SHOW OROGRAPHIC SNOW SHOWERS THROUGH
THE MORNING...PRIMARILY NORTH OF INTERSTATE 70...THEN THE SNOW
SHOWERS DRY UP. ACROSS THE NORTHEAST PLAINS...DRY WITH THE
EXCEPTION OF MAYBE AN EARLY MORNING SHOWER ALONG THE NORTHERN
BORDER. GUSTY WINDS THE MAIN ISSUED THROUGH THE DAY ON
SUNDAY....ESPECIALLY ALONG THE NORTHERN BORDER. NO HIGHLIGHTS BUT
WINDY THROUGH THE DAY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 233 PM MDT SAT APR 23 2016
SEVERAL SHORT WAVE TROUGHS MOVING OFF THE PACIFIC AND INTO THE
SOUTHWESTERN U.S. WILL KEEP AN ACTIVE WEATHER PATTERN IN PLACE.
ON MONDAY...ONE SHORT WAVE WILL MOVE INTO THE SOUTHWEST U.S. AND
ATTEMPT TO CLOSE OFF IN THE GREAT BASIN TO NEAR LAS VEGAS. AHEAD
OF THIS...DEEP LAYER Q-G LIFT WILL OCCUR ACROSS COLORADO...
RESULTING IN INCREASING SHOWER AND AFTERNOON STORM COVERAGE. MOST
OF THIS WILL INITIALLY OCCUR IN THE MOUNTAINS...BUT THEN SPREAD
OFF THE TERRAIN AND/OR DEVELOP ON THE PLAINS AS THE AIRMASS
DESTABILIZES LATE IN THE AFTERNOON THROUGH MONDAY NIGHT.
BY TUESDAY...MODELS ARE STILL WOBBLING WITH THE EVENTUAL LOCATION
OF THE UPPER LOW AS IT MOVES EAST TOWARD THE PLAINS. THE LATEST
ECMWF WAS MUCH MORE CONSOLIDATED AND MOVES THE UPPER LOW RIGHT
OVER THE FORECAST AREA. THE CANADIAN WAS ALSO MORE TIGHTLY WOUND
BUT FARTHER NORTH...WHILE MOST OTHER MODELS INCLUDING THE GFS AND
ITS ENSEMBLES...AND THE 00Z ECMWF WERE MORE OPEN WITH THE TROUGH.
DESPITE THE UNCERTAINTY WITH THE EXACT TRACK...THE MAIN PICTURE
THROUGH THIS TIME WILL BE UNSETTLED WEATHER WITH A GOOD CHANCE OF
SHOWERS AND THUNDERSTORMS. THERE WILL BE SNOW IN THE MOUNTAINS AND
HIGHER FOOTHILLS...AND SOME THREAT OF SNOW SPREADING DOWN ONTO
HIGHER ELEVATIONS OF THE PLAINS TUESDAY NIGHT WITH COLDER AIR
ARRIVING ALOFT. IN FACT...THE 12Z ECMWF SHOWED SNOW AS EARLY AS
TUESDAY AFTERNOON ALONG THE FRONT RANGE GIVEN ITS DEEPER AND
COLDER SOLUTION. MEANWHILE IF THE STORM IS SLOWER THAN THE THREAT
OF STRONGER STORMS WILL EXIST OVER THE EASTERN PLAINS.
THAT SYSTEM EVENTUALLY KICKS OUT TO THE NORTHEAST WEDNESDAY SO
MAINLY DRIER BUT COOL WEATHER EXPECTED. STILL CANT RULE OUT A FEW
LINGERING SHOWERS BUT SHOULD BE ISOLATED.
THE NEXT STORM SYSTEM MAY BEGIN TO IMPACT THE FORECAST AREA BY
LATE THURSDAY AS IT TOO DIVES INTO THE SOUTHWEST U.S. SIMILAR TO
MONDAY/TUESDAY SYSTEM. THIS STORM SYSTEM WILL LIKELY BRING MORE
SHOWERS AND THUNDERSTORMS...AND MOUNTAIN SNOWFALL...TO THE REGION
LATE THURSDAY THROUGH FRIDAY NIGHT. A FEW SHOWERS COULD LINGER
INTO SATURDAY. DAYTIME HIGHS WILL AVERAGE SEVERAL DEGREES BELOW
NORMAL DURING THIS MOIST AND UNSETTLED PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 956 PM MDT SAT APR 23 2016
VFR CONDITIONS EXPECTED THROUGH SUNDAY EVENING. A WEAK SURGE FROM
THE NORTH SEEMS TO BE SPREADING SOUTH FROM THE CO/WY BORDER. THIS
WILL LIKELY SHOW UP AT KDEN AND PERHAPS KBJC IN THE NEXT HOUR.
THEN FROM THERE...WINDS ARE DIFFICULT TO FORECAST AS HI RES MODELS
HAVE LIGHT AND VARIABLE UNTIL AFTER 08Z WHEN SOUTHERLY WINDS
INCREASE AGAIN. EVEN THE STRONG DOWNSLOPE WINDS EXPECTED AT
KBJC ARE BEING DOWNPLAYED ANY MORE. MAY NOT SEE THE HIGHER WINDS
UNTIL SUNDAY MORNING. HAVE DECREASED SPEEDS SOME TO REFLECT THIS
TREND. ON SUNDAY...GUSTY WEST- NORTHWEST WINDS AT ALL THE AIRPORT
EXPECTED AFTER 18Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KRIEDERMAN
SHORT TERM...COOPER
LONG TERM...BARJENBRUCH
AVIATION...KRIEDERMAN
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
838 PM MDT SAT APR 23 2016
.UPDATE...
ISSUED AT 838 PM MDT SAT APR 23 2016
MAIN FRONT HAS PUSHED THROUGH THE AREA WITH SHOWERS AND
THUNDERSTORMS DIMINISHING WEST TO EAST...WITH SOME ACTIVITY
REMAINING OVER THE FAR NORTHEASTERN PLAINS. A DRY SLOT NOTED ON
WATER VAPOR SATELLITE OVER CENTRAL COLORADO WILL KEEP THE REST OF
THE EVENING MAINLY DRY BEFORE WRAPAROUND MOISTURE AROUND THE
WYOMING UPPER LOW WILL PUSH SNOW BACK INTO THE NORTHERN MOUNTAINS.
HAVE UPDATED TONIGHTS WEATHER GRIDS TO REFLECT THESE TRENDS. STILL
EXPECTING THE WINDS TO CONTINUE IN THE HIGH COUNTRY AND FOOTHILLS
OVERNIGHT...INCREASING TOWARD MORNING.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 233 PM MDT SAT APR 23 2016
THE UPPER TROUGH OVER NORTHERN UTAH/SOUTHWESTERN WYOMING THIS
AFTERNOON WILL TRACK TO THE NORTHEAST INTO CENTRAL WYOMING
OVERNIGHT...THEN INTO SOUTH DAKOTA BY LATE AFTN. BEST QG ASCENT
ASSOCIATED WITH THIS PASSING TROUGH WILL AROUND 00Z THEN STRONGER
QG DESCENT BUILDS IN FROM THE WEST. THE LATEST HRRR DEVELOPS A
LITTLE BETTER SHOWER/TSTMS COVERAGE BUT IT LOOKS OVERDONE COMPARED
TO PRVS RUNS. BEST CHC FOR MOUNTAIN SNOW WILL BE IN ZONES 31 AND
33...WITH BEST SHOWER/TSTM POTENTIAL ALONG THE NORTHEAST BORDER
OF THE NORTHEAST PLAINS. SHOWERS/TSTMS LATE THIS AFTN AND EVENING
COULD PACK SOME FAIRLY STRONG GUSTS...UP TO 50 MPH ACROSS THE
NORTHEAST PLAINS. STRONG JETSTREAM WINDS ALOFT OVER THE CWA THIS
AFTN SO EVEN STRONGER GUSTS IN THE MOUNTAINS/HIGHER FOOTHILLS TO
70 MPH. STRONG SUBSIDENCE LATER THIS EVENING WILL PRODUCE
AN AMPLIFIED MOUNTAIN WAVE SO STRONGER GUSTS WILL PERSIST ACROSS
THOSE AREAS OVERNIGHT. STRONGER WINDS ACROSS THE NORTHEAST PLAINS
SHOULD SUBSIDE AFT 03Z WITH THE DISSIPATION OF ANY SHOWERS. ON
SUNDAY...MDLS STILL SHOW OROGRAPHIC SNOW SHOWERS THROUGH
THE MORNING...PRIMARILY NORTH OF INTERSTATE 70...THEN THE SNOW
SHOWERS DRY UP. ACROSS THE NORTHEAST PLAINS...DRY WITH THE
EXCEPTION OF MAYBE AN EARLY MORNING SHOWER ALONG THE NORTHERN
BORDER. GUSTY WINDS THE MAIN ISSUED THROUGH THE DAY ON
SUNDAY....ESPECIALLY ALONG THE NORTHERN BORDER. NO HIGHLIGHTS BUT
WINDY THROUGH THE DAY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 233 PM MDT SAT APR 23 2016
SEVERAL SHORT WAVE TROUGHS MOVING OFF THE PACIFIC AND INTO THE
SOUTHWESTERN U.S. WILL KEEP AN ACTIVE WEATHER PATTERN IN PLACE.
ON MONDAY...ONE SHORT WAVE WILL MOVE INTO THE SOUTHWEST U.S. AND
ATTEMPT TO CLOSE OFF IN THE GREAT BASIN TO NEAR LAS VEGAS. AHEAD
OF THIS...DEEP LAYER Q-G LIFT WILL OCCUR ACROSS COLORADO...
RESULTING IN INCREASING SHOWER AND AFTERNOON STORM COVERAGE. MOST
OF THIS WILL INITIALLY OCCUR IN THE MOUNTAINS...BUT THEN SPREAD
OFF THE TERRAIN AND/OR DEVELOP ON THE PLAINS AS THE AIRMASS
DESTABILIZES LATE IN THE AFTERNOON THROUGH MONDAY NIGHT.
BY TUESDAY...MODELS ARE STILL WOBBLING WITH THE EVENTUAL LOCATION
OF THE UPPER LOW AS IT MOVES EAST TOWARD THE PLAINS. THE LATEST
ECMWF WAS MUCH MORE CONSOLIDATED AND MOVES THE UPPER LOW RIGHT
OVER THE FORECAST AREA. THE CANADIAN WAS ALSO MORE TIGHTLY WOUND
BUT FARTHER NORTH...WHILE MOST OTHER MODELS INCLUDING THE GFS AND
ITS ENSEMBLES...AND THE 00Z ECMWF WERE MORE OPEN WITH THE TROUGH.
DESPITE THE UNCERTAINTY WITH THE EXACT TRACK...THE MAIN PICTURE
THROUGH THIS TIME WILL BE UNSETTLED WEATHER WITH A GOOD CHANCE OF
SHOWERS AND THUNDERSTORMS. THERE WILL BE SNOW IN THE MOUNTAINS AND
HIGHER FOOTHILLS...AND SOME THREAT OF SNOW SPREADING DOWN ONTO
HIGHER ELEVATIONS OF THE PLAINS TUESDAY NIGHT WITH COLDER AIR
ARRIVING ALOFT. IN FACT...THE 12Z ECMWF SHOWED SNOW AS EARLY AS
TUESDAY AFTERNOON ALONG THE FRONT RANGE GIVEN ITS DEEPER AND
COLDER SOLUTION. MEANWHILE IF THE STORM IS SLOWER THAN THE THREAT
OF STRONGER STORMS WILL EXIST OVER THE EASTERN PLAINS.
THAT SYSTEM EVENTUALLY KICKS OUT TO THE NORTHEAST WEDNESDAY SO
MAINLY DRIER BUT COOL WEATHER EXPECTED. STILL CANT RULE OUT A FEW
LINGERING SHOWERS BUT SHOULD BE ISOLATED.
THE NEXT STORM SYSTEM MAY BEGIN TO IMPACT THE FORECAST AREA BY
LATE THURSDAY AS IT TOO DIVES INTO THE SOUTHWEST U.S. SIMILAR TO
MONDAY/TUESDAY SYSTEM. THIS STORM SYSTEM WILL LIKELY BRING MORE
SHOWERS AND THUNDERSTORMS...AND MOUNTAIN SNOWFALL...TO THE REGION
LATE THURSDAY THROUGH FRIDAY NIGHT. A FEW SHOWERS COULD LINGER
INTO SATURDAY. DAYTIME HIGHS WILL AVERAGE SEVERAL DEGREES BELOW
NORMAL DURING THIS MOIST AND UNSETTLED PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 838 PM MDT SAT APR 23 2016
VFR CONDITIONS EXPECTED. THE STRONG SOUTHWEST TO WEST WINDS WILL
BEGIN SUBSIDING AND BECOME MORE SOUTH-SOUTHWESTERLY OVERNIGHT. AT
KBJC...GUSTY WEST-SOUTHWEST WINDS WILL CONTINUE OVERNIGHT...SO
MAY SEE GUST TO 40-45KT OVERNIGHT WITH THE DEVELOPMENT OF
DOWNSLOPE WINDS. ON SUNDAY...GUSTY WEST- NORTHWEST WINDS AT ALL
THE AIRPORT EXPECTED AFTER 18Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KRIEDERMAN
SHORT TERM...COOPER
LONG TERM...BARJENBRUCH
AVIATION...KRIEDERMAN
AREA FORECAST DISCUSSION
NWS TAUNTON MA
518 PM EDT FRI APR 22 2016
.SYNOPSIS...
A COLD FRONT OVER NEW YORK CROSSES SOUTHERN NEW ENGLAND TONIGHT
AND MOVES OFFSHORE SATURDAY. HIGH PRESSURE THEN BUILDS FOR LATER
SATURDAY AND SUNDAY BRINGING DRY AND SEASONABLE WEATHER. A FRONT WILL
PUSH SLOWLY ACROSS THE REGION MONDAY AND TUESDAY WHICH WILL BRING
MUCH NEEDED SHOWERS TO THE REGION. DRY AND SEASONABLE CONDITIONS
SHOULD MOVE IN AROUND THE MIDDLE OF NEXT WEEK. THEN A LOW PRESSURE
SYSTEM MAY BRING ADDITIONAL RAINFALL TO OUR AREA THIS UPCOMING
THURSDAY AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
THIS EVENING/EARLY NIGHT...
NORTHERN STREAM SHORTWAVE AND SUPPORTING JET MOVE ACROSS NEW
ENGLAND THIS EVENING. FAVORABLE JET DYNAMICS ALONG WITH LI AROUND
-2 AND SBCAPE AROUND 1000 HAVE BEEN HELPING TO GENERATE SHOWERS
AND A FEW TSTMS OVER THE BERKSHIRES AND HUDSON VALLEY WHICH THEN
MOVE ACROSS WESTERN AND NORTHERN MASS. THESE FAVORABLE CONDITIONS
WILL FADE AFTER SUNSET...BUT UNTIL THEN EXPECT SHOWERS AND A FEW
TSTMS OVER WESTERN/NORTHERN MASS AND NORTHERN CT.
TONIGHT...
THE NEW YORK COLD FRONT EXTRAPOLATES TO THE BERKSHIRES 6-8
PM...THE WORCESTER HILLS 9-11 PM...AND THE EASTERN COAST 12-2 AM.
MEANWHILE...AN OPEN SHORTWAVE OVER OHIO IS MOVING EAST AND WILL
REACH THE MID ATLANTIC COAST BY SATURDAY MORNING. THE SHORTWAVE IS
SUPPORTED BY AN 85-KNOT JET THAT WILL OVERLAY NEW JERSEY AND LONG
ISLAND OVERNIGHT. THIS SHORTWAVE MAY TURN THE UPPER FLOW MORE
PARALLEL TO THE SURFACE COLD FRONT...SLOWING THE FORWARD PROGRESS
OF THAT FRONT. THE SHORTWAVE AND JET MAY ALSO GENERATE A WAVE
ALONG THE FRONT OVERNIGHT. BOTH THE GFS AND HRRR ARE HINTING AT
THIS. THE ECMWF SURFACE MSLP FIELD SHOWS A BAGGINESS SOUTH OF NEW
ENGLAND AT 12Z SAT THAT ALSO HINTS AT THIS.
DEW POINTS HAVE CLIMBED INTO THE 50S. WATER TEMPERATURES ARE IN
THE MID TO UPPER 40S. THIS COOLING OF THE MOIST AIR MAY CREATE
AREAS OF FOG THAT WOULD AFFECT THE SOUTH COAST.
WHILE THE EVENING PCPN TAPERS OFF...THE CHANCE OF SHOWERS ALONG
THE FRONT WILL LINGER UNTIL FROPA. THE UPPER SHORTWAVE AND JET
WILL MAINTAIN A CHANCE OF SHOWERS THROUGH THE NIGHT WITH THE BEST
CHANCE ALONG THE SOUTH COAST. WE WILL MAINTAIN CHANCE POPS THROUGH
THE NIGHT MOST PLACES AND CARRY LIKELY POPS ALONG/SOUTH OF A
HARTFORD-PROVIDENCE LINE. WITH DEW POINTS IN THE UPPER 40S AND
50S...EXPECT MIN TEMPS IN THIS SAME RANGE.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
UPPER TROUGH MOVES EAST OF NEW ENGLAND SATURDAY AND PUSHES THE
SURFACE FRONT WELL SOUTH OF OUR AREA. LEFTOVER SHOWERS...MAINLY
OVER RI/SOUTHEAST MASS...SHOULD MOVE OFF WITH THE TROUGH. HIGH
PRESSURE OVER CANADA WILL BUILD INTO NEW ENGLAND BRINGING DRIER
AIR AND CLEARING SKIES. MIXING IS FORECAST TO 900 MB...POSSIBLY A
LITTLE HIGHER. TEMPS AT THAT HEIGHT WOULD SUPPORT MAX SFC TEMPS IN
THE 60S. WINDS IN THE MIXED LAYER WILL BE 15-20 KNOTS...WHICH MAY
BE MIXED TO THE SURFACE IN GUSTS.
AS THE HIGH BUILDS IN...THE PRESSURE GRADIENT WILL LESSEN. NOT
CLEAR WHETHER IT WILL DIMINISH ENOUGH TO ALLOW THE SURFACE AIR TO
DECOUPLE AND ALLOW RADIATIONAL COOLING. DEW POINTS WILL FALL INTO
THE 20S...WHICH WOULD BE QUITE A CHILLY START TO THE DAY IF MINS
REACHED THAT LOW. WE WILL ALLOW A LIGHT NORTH WIND OVERNIGHT AND
KEEP TEMPS ABOVE FREEZING MOST PLACES. THE BEST CHANCE OF
DECOUPLING AND RADIATIONAL COOLING WILL BE IN THE VALLEYS OF
NORTHERN AND WESTERN MASS...WHERE THERE WILL BE THE BEST CHANCE OF
DIPPING BELOW 30. WE WILL NEED TO MONITOR THIS...SUCH COOLING MAY
BE ABLE TO EXTEND FARTHER SOUTH AND EAST.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
OVERVIEW...
LONG WAVE TROUGH ALONG THE EASTERN SEABOARD EARLY THIS WEEKEND
WILL SHIFT E AS OVERALL NORTH AMERICAN UPPER LEVEL STEERING
CURRENTS REMAIN PROGRESSIVE. BROAD H5 VORTEX ELONGATES FROM THE
ARCTIC CIRCLE INTO LABRADOR AND NEWFOUNDLAND BY SUNDAY...WITH THE
BASE OF THE VORTEX KEEPING A FAST W-NW UPPER FLOW ACROSS THE
REGION FOR MOST IF NOT ALL OF THE UPCOMING WEEK. THE NEXT
APPROACHING FRONT WILL MOVE INTO THE REGION BY THE BEGINNING OF
THE WORK WEEK AND...AS IT BECOMES PARALLEL TO THE UPPER FLOW...WILL
SEE MUCH NEEDED RAIN SHOWERS MOVE ACROSS AS THE FRONT SLOWLY PUSHES
OFFSHORE.
CANADIAN HIGH PRESSURE BRINGS DRY CONDITIONS WEDNESDAY. THEN LOW
CONFIDENCE ON THE TIMING AND TRACK AS A QUICK MOVING LOW PRESSURE
SYSTEM THAT SHOULD APPROACH THE REGION OUT OF THE OHIO VALLEY AND
SOUTHERN GREAT LAKES TOWARDS THE END OF THE UPCOMING WORKWEEK.
DETAILS...
SUNDAY...MODERATE TO HIGH CONFIDENCE.
HIGH PERSSURE PASSES OVERHEAD DURING THE DAY. ANTICIAPTE MOSTLY
SUNNY SKIES...THOUGH THE FRONT TO THE NORTHWEST OF OUR AREA MAY
ALLOW FOR SOME AFTERNOON CIRRUS AND MID DECK CLOUDS. SEA BREEZES ARE
LIKELY ALONG THE COAST BY THE AFTERNOON. TEMPS NEAR NORMAL TO A FEW
DEGREES BELOW NORMAL.
SUNDAY NIGHT THROUGH TUESDAY...MODERATE CONFIDENCE.
CLOUDS WILL CONTINUE TO INCREASE SUNDAY NIGHT AS A COLD FRONT MOVES
OUT OF N NY STATE AND NORTHERN NEW ENGLAND. THE FRONT WILL MOVE
SLOWLY TO THE SOUTHEAST...BUT LOOKS LIKE IT WILL REMAIN DRY THROUGH
AT LEAST MIDNIGHT. THE POTENTIAL EXISTS FOR A FEW SHOWERS LATE
SUNDAY NIGHT...MAINLY ACROSS N MA.
THE FRONT LOOKS TO SLOW ITS FORWARD PROGRESS AS IT BECOMES PARALLEL
TO THE UPPER LEVEL WIND FLOW DURING MONDAY. CONTINUE TO EXPECT A
COUPLE OF WAVES OF LOW PRES MOVE ALONG THE FRONT...WHICH WILL ALSO
TEND TO SLOW THE FRONT DOWN. STARTING TO SEE A BIT MORE MOISTURE
CONVERGENCE SETTING UP AS THE FRONT CROSSES...ESPECIALLY MONDAY
NIGHT AND TUESDAY...BRINGING SOME MUCH NEEDED RAINFALL.
FORECAST QPF AMOUNTS LOOK TO BE ON THE ORDER OF 0.5 TO 1 INCH FROM
MONDAY AFTERNOON INTO TUESDAY.
AS THE FRONT CROSSES THE REGION LATE MON NIGHT AND TUESDAY...
COOLER AIR WORKS IN AS WINDS SHIFT TO N AND NE. HIGHS WILL BE CLOSE
TO SEASONAL NORMALS ON MONDAY...BUT WILL FALL DOWN TO SEVERAL
DEGREES BELOW SEASONAL LEVELS ON TUESDAY.
TUESDAY NIGHT AND WEDNESDAY...MODERATE CONFIDENCE.
THE FRONT SHOULD PUSH SOUTH OF OUR AREA DURING TUESDAY NIGHT...WITH
CANADIAN HIGH PRESSURE BUILDING SOUTHEASTWARD. HAVE VERY LOW CHANCE
POPS TO START TUESDAY NIGHT. OTHERWISE EXPECT CLEARING SKIES
TUESDAY NIGHT.
FAST FLOW ALOFT WILL PUSH HIGH PRES ACROSS THE REGION ON
WEDNESDAY WITH DRY BUT COOL CONDITIONS. MOSTLY SUNNY SKIES FORECAST.
WEDNESDAY NIGHT THRU FRIDAY...LOW CONFIDENCE.
A LOT OF QUESTIONS REMAIN ON THE TIMING OF A FAST MOVING LOW
PRESSURE SYSTEM THAT IS EXPECTED TO AFFECT OUR AREA DURING
THISTIMEFRAME. AT THIS POINT HAVE DRY CONDITIONS FOR MOST OF WED
NIGHT...FOLLOWED BY CHANCE TO SLIGHT CHANCE POPS FOR SHOWERS THU
INTO FRI.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SATURDAY NIGHT/...
510 PM UDPATE...CORRECTION TO MENTION 23Z.
THRU 23Z...MODERATE CONFIDENCE. SHOWERS AND ISOLATED T-STORMS
MOVING MAINLY W-E ACROSS SOUTHERN NEW ENGLAND...WITH THE BEST
CHANCE FOR T-STORMS WESTERN-CENTRAL MA AND NORTHERN CT. SOME OF
THE SHOWERS AND ESPECIALLY T-STORMS HAVE BEEN PRODUCING OUTFLOW
BOUNDARIES RESULTING IN ABRUPT AND SUBSTANTIAL WIND SHIFTS IN
VARIABLE DIRECTIONS. THIS WILL BE A RISK THRU 23Z. MAINLY VFR
CONDITIONS ACROSS THE AREA THRU 23Z...WITH LOCALIZED MVFR
CIGS/VSBYS WHERE MODERATE TO HEAVY RAINFALL OCCURS.
AFTER 23Z...HIGH CONFIDENCE. GENERALLY VFR THROUGH MIDNIGHT.
SHOWERS AND A FEW THUNDERSTORMS THIS EVENING IN WESTERN AND
CENTRAL MASS AND NORTHERN CT. SOME SHOWERS MAY BRIEFLY LOWER CIGS
AND VSBYS TO MVFR.
OVERNIGHT...MODERATE CONFIDENCE. AFTER THE FIRST SET OF SHOWERS
DIMINISHES...A SECOND AREA OF SHOWERS WILL MOVE UP FROM THE
SOUTHWEST AFTER MIDNIGHT. EXPECT VFR CIGS TO LOWER TO MVFR
OVERNIGHT IN A FEW SHOWERS...WHILE SOUTH COASTAL NEW ENGLAND WILL
LOWER TO IFR OR LIFR IN SHOWERS AND DEVELOPING FOG.
SATURDAY AND SATURDAY NIGHT... HIGH CONFIDENCE. VFR CONDITIONS IN
THE WEST. CIGS/VSBYS IMPROVE TO VFR IN THE EAST. NORTH WIND AROUND
10 KNOTS WITH POTENTIAL GUSTS NEAR 20 KNOTS IN THE AFTERNOON.
WINDS DIMINISH TOWARD EVENING.
KBOS TERMINAL...MODERATE TO HIGH CONFIDENCE. EAST SEA BREEZE
SHOULD SWITCH TO SOUTH-SOUTHWEST BY LATE AFTERNOON. VFR CONDITIONS
SHOULD PERSIST THROUGH EARLY EVENING...BUT LEFTOVER SHOWERS FROM
WESTERN MASS MAY BRING BRIEF MVFR CIGS/VSBYS THIS EVENING. ANOTHER
AREA OF SHOWERS MOVES THROUGH LATER TONIGHT WITH MVFR CONDITIONS.
KBDL TERMINAL...MODERATE TO HIGH CONFIDENCE. MAINLY VFR. HOWEVER...BRIEF
LOWER CONDITIONS POSSIBLE THIS EVENING IN SCATTERED SHOWERS AND
PERHAPS A THUNDERSTORM. ALSO A PERIOD OF MVFR CIGS POSSIBLE
OVERNIGHT.
OUTLOOK /SUNDAY THROUGH WEDNESDAY/...
SUNDAY AND SUNDAY NIGHT...HIGH CONFIDENCE. VFR SUNDAY INTO SUNDAY
EVENING. MAY SEE MVFR CIGS/VSBYS MOVE INTO NORTHERN AREAS MAINLY
NEAR AND N OF THE MASS PIKE AFTER MIDNIGHT SUNDAY NIGHT.
MONDAY AND TUESDAY...MODERATE CONFIDENCE. AREAS OF MVFR
CIGS/VSBYS IN SHOWERS AND PATCHY FOG. CONDITIONS SHOULD IMPROVE
FROM N-S TUE NIGHT...THOUGH TIMING IS IN QUESTION.
WEDNESDAY...MODERATE CONFIDENCE. VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SATURDAY NIGHT/...
TONIGHT...MODERATE TO HIGH CONFIDENCE.
PERSISTENT SOUTHWEST FLOW AHEAD OF A COLD FRONT WILL REMAIN BELOW
20 KNOTS. THE PERSISTENT FLOW WILL BUILD SEAS A LITTLE WITH 5 FOOT
HEIGHTS ON THE OUTER WATERS SOUTH OF THE ISLANDS. SMALL CRAFT
ADVISORY CONTINUES ON THOSE WATERS. AREAS OF FOG DEVELOP DURING
THE NIGHT WHICH MAY BECOME LOCALLY DENSE...RESULTING IN POOR
VISIBILITY. WINDS WILL SHIFT LATER AT NIGHT AND COME FROM THE
NORTH OR NORTHWEST.
SATURDAY AND SATURDAY NIGHT...NORTH WINDS WITH GUSTS TO 20 KNOTS
SATURDAY AND 20 TO 25 KNOTS SATURDAY NIGHT. SEAS WILL BE 3-4 FEET
SATURDAY. HEIGHTS OF 4-6 FEET POSSIBLE ON THE EASTERN OUTER WATERS
SATURDAY NIGHT. A SMALL CRAFT ADVISORY MAY BE NEEDED ON SOME OF
THE WATERS.
OUTLOOK /SUNDAY THROUGH WEDNESDAY/...
SUNDAY...MODERATE CONFIDENCE. N WINDS VEERING TO THE SE ON SUNDAY.
GUSTS UP TO 25 KT POSSIBLE DURING THE MORNING...MAINLY ALONG THE
OUTER COASTAL WATERS. LINGERING 5 FOOT SEAS ON THE OUTER COASTAL
WATERS SHOULD GRADUALLY SUBSIDE DURING THE DAY.
MONDAY...MODERATE CONFIDENCE.
WINDS AND SEAS BELOW SCA THRESHOLDS. MAY SEE VSBY RESTRICTIONS IN
SCATTERED SHOWERS AND PATCHY FOG MONDAY.
MONDAY NIGHT AND TUESDAY...LOW TO MODERATE CONFIDENCE.
COLD FRONT SLOWLY MOVES FROM N TO S ACROSS THE WATERS. S WINDS
BECOME N DURING MON NIGHT/TUE. THEN THE N WINDS MAY GUST UP TO 20 KT
DURING TUE. SEAS BUILD UP TO 5-6 FT ACROSS THE SOUTHERN WATERS
MONDAY NIGHT AND TUESDAY...AND MAY REACH TO E OF CAPE COD DURING
TUESDAY. SHOULD HAVE SUBSIDING SEAS TUESDAY NIGHT. VSBY RESTRICTIONS
IN SHOWERS AND PATCHY FOG.
WEDNESDAY...MODERATE CONFIDENCE.
WINDS/SEAS BELOW SCA THRESHOLDS.
&&
.FIRE WEATHER...
SATURDAY...WIDELY SCATTERED SHOWERS MAY LINGER ACROSS SE MA/E RI
SATURDAY MORNING WITH N-NW WIND GUSTS UP TO 20 MPH. THESE SHOULD
PUSH OFFSHORE BY MIDDAY. DRY CONDITIONS WILL TAKE OVER SATURDAY
AFTERNOON WITH NORTH TO NORTHWEST WINDS USHERING LOWERING
DEWPOINTS. MINIMUM RELATIVE HUMIDITIES WILL BE FROM 25 TO 40
PERCENT NORTH AND WEST OF I-95 AND 40 TO 60 PERCENT TO THE SOUTH
AND EAST.
SUNDAY...HIGH PRESSURE WILL MOVE ACROSS THE REGION. LIGHT N WINDS AT
5 TO 10 MPH WILL BECOME SW DURING THE AFTERNOON...WITH SEA BREEZES
PROBABLE. MINIMUM RH VALUES WILL BE FROM 20 TO 30 PERCENT FOR MUCH
OF THE AREA...EXCEPT 35 TO 45 PERCENT ALONG THE IMMEDIATE COAST.
MONDAY AND TUESDAY...A SLOW MOVING FRONT COULD BRING A SOAKING
RAINFALL TO SOUTHERN NEW ENGLAND. THE BEST CHANCE FOR APPRECIABLE
RAIN IS MONDAY AFTERNOON THRU TUESDAY MORNING. AT THIS TIME THE
POTENTIAL EXISTS FOR 0.5 TO AROUND 1.0 INCH OF RAINFALL.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT SATURDAY FOR ANZ255-256.
&&
$$
SYNOPSIS...WTB/NMB
NEAR TERM...WTB/NMB
SHORT TERM...WTB
LONG TERM...NMB
AVIATION...WTB/NMB
MARINE...WTB/NMB
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS TAUNTON MA
515 PM EDT FRI APR 22 2016
.SYNOPSIS...
A COLD FRONT OVER NEW YORK CROSSES SOUTHERN NEW ENGLAND TONIGHT
AND MOVES OFFSHORE SATURDAY. HIGH PRESSURE THEN BUILDS FOR LATER
SATURDAY AND SUNDAY BRINGING DRY AND SEASONABLE WEATHER. A FRONT WILL
PUSH SLOWLY ACROSS THE REGION MONDAY AND TUESDAY WHICH WILL BRING
MUCH NEEDED SHOWERS TO THE REGION. DRY AND SEASONABLE CONDITIONS
SHOULD MOVE IN AROUND THE MIDDLE OF NEXT WEEK. THEN A LOW PRESSURE
SYSTEM MAY BRING ADDITIONAL RAINFALL TO OUR AREA THIS UPCOMING
THURSDAY AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
THIS EVENING/EARLY NIGHT...
NORTHERN STREAM SHORTWAVE AND SUPPORTING JET MOVE ACROSS NEW
ENGLAND THIS EVENING. FAVORABLE JET DYNAMICS ALONG WITH LI AROUND
-2 AND SBCAPE AROUND 1000 HAVE BEEN HELPING TO GENERATE SHOWERS
AND A FEW TSTMS OVER THE BERKSHIRES AND HUDSON VALLEY WHICH THEN
MOVE ACROSS WESTERN AND NORTHERN MASS. THESE FAVORABLE CONDITIONS
WILL FADE AFTER SUNSET...BUT UNTIL THEN EXPECT SHOWERS AND A FEW
TSTMS OVER WESTERN/NORTHERN MASS AND NORTHERN CT.
TONIGHT...
THE NEW YORK COLD FRONT EXTRAPOLATES TO THE BERKSHIRES 6-8
PM...THE WORCESTER HILLS 9-11 PM...AND THE EASTERN COAST 12-2 AM.
MEANWHILE...AN OPEN SHORTWAVE OVER OHIO IS MOVING EAST AND WILL
REACH THE MID ATLANTIC COAST BY SATURDAY MORNING. THE SHORTWAVE IS
SUPPORTED BY AN 85-KNOT JET THAT WILL OVERLAY NEW JERSEY AND LONG
ISLAND OVERNIGHT. THIS SHORTWAVE MAY TURN THE UPPER FLOW MORE
PARALLEL TO THE SURFACE COLD FRONT...SLOWING THE FORWARD PROGRESS
OF THAT FRONT. THE SHORTWAVE AND JET MAY ALSO GENERATE A WAVE
ALONG THE FRONT OVERNIGHT. BOTH THE GFS AND HRRR ARE HINTING AT
THIS. THE ECMWF SURFACE MSLP FIELD SHOWS A BAGGINESS SOUTH OF NEW
ENGLAND AT 12Z SAT THAT ALSO HINTS AT THIS.
DEW POINTS HAVE CLIMBED INTO THE 50S. WATER TEMPERATURES ARE IN
THE MID TO UPPER 40S. THIS COOLING OF THE MOIST AIR MAY CREATE
AREAS OF FOG THAT WOULD AFFECT THE SOUTH COAST.
WHILE THE EVENING PCPN TAPERS OFF...THE CHANCE OF SHOWERS ALONG
THE FRONT WILL LINGER UNTIL FROPA. THE UPPER SHORTWAVE AND JET
WILL MAINTAIN A CHANCE OF SHOWERS THROUGH THE NIGHT WITH THE BEST
CHANCE ALONG THE SOUTH COAST. WE WILL MAINTAIN CHANCE POPS THROUGH
THE NIGHT MOST PLACES AND CARRY LIKELY POPS ALONG/SOUTH OF A
HARTFORD-PROVIDENCE LINE. WITH DEW POINTS IN THE UPPER 40S AND
50S...EXPECT MIN TEMPS IN THIS SAME RANGE.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
UPPER TROUGH MOVES EAST OF NEW ENGLAND SATURDAY AND PUSHES THE
SURFACE FRONT WELL SOUTH OF OUR AREA. LEFTOVER SHOWERS...MAINLY
OVER RI/SOUTHEAST MASS...SHOULD MOVE OFF WITH THE TROUGH. HIGH
PRESSURE OVER CANADA WILL BUILD INTO NEW ENGLAND BRINGING DRIER
AIR AND CLEARING SKIES. MIXING IS FORECAST TO 900 MB...POSSIBLY A
LITTLE HIGHER. TEMPS AT THAT HEIGHT WOULD SUPPORT MAX SFC TEMPS IN
THE 60S. WINDS IN THE MIXED LAYER WILL BE 15-20 KNOTS...WHICH MAY
BE MIXED TO THE SURFACE IN GUSTS.
AS THE HIGH BUILDS IN...THE PRESSURE GRADIENT WILL LESSEN. NOT
CLEAR WHETHER IT WILL DIMINISH ENOUGH TO ALLOW THE SURFACE AIR TO
DECOUPLE AND ALLOW RADIATIONAL COOLING. DEW POINTS WILL FALL INTO
THE 20S...WHICH WOULD BE QUITE A CHILLY START TO THE DAY IF MINS
REACHED THAT LOW. WE WILL ALLOW A LIGHT NORTH WIND OVERNIGHT AND
KEEP TEMPS ABOVE FREEZING MOST PLACES. THE BEST CHANCE OF
DECOUPLING AND RADIATIONAL COOLING WILL BE IN THE VALLEYS OF
NORTHERN AND WESTERN MASS...WHERE THERE WILL BE THE BEST CHANCE OF
DIPPING BELOW 30. WE WILL NEED TO MONITOR THIS...SUCH COOLING MAY
BE ABLE TO EXTEND FARTHER SOUTH AND EAST.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
OVERVIEW...
LONG WAVE TROUGH ALONG THE EASTERN SEABOARD EARLY THIS WEEKEND
WILL SHIFT E AS OVERALL NORTH AMERICAN UPPER LEVEL STEERING
CURRENTS REMAIN PROGRESSIVE. BROAD H5 VORTEX ELONGATES FROM THE
ARCTIC CIRCLE INTO LABRADOR AND NEWFOUNDLAND BY SUNDAY...WITH THE
BASE OF THE VORTEX KEEPING A FAST W-NW UPPER FLOW ACROSS THE
REGION FOR MOST IF NOT ALL OF THE UPCOMING WEEK. THE NEXT
APPROACHING FRONT WILL MOVE INTO THE REGION BY THE BEGINNING OF
THE WORK WEEK AND...AS IT BECOMES PARALLEL TO THE UPPER FLOW...WILL
SEE MUCH NEEDED RAIN SHOWERS MOVE ACROSS AS THE FRONT SLOWLY PUSHES
OFFSHORE.
CANADIAN HIGH PRESSURE BRINGS DRY CONDITIONS WEDNESDAY. THEN LOW
CONFIDENCE ON THE TIMING AND TRACK AS A QUICK MOVING LOW PRESSURE
SYSTEM THAT SHOULD APPROACH THE REGION OUT OF THE OHIO VALLEY AND
SOUTHERN GREAT LAKES TOWARDS THE END OF THE UPCOMING WORKWEEK.
DETAILS...
SUNDAY...MODERATE TO HIGH CONFIDENCE.
HIGH PERSSURE PASSES OVERHEAD DURING THE DAY. ANTICIAPTE MOSTLY
SUNNY SKIES...THOUGH THE FRONT TO THE NORTHWEST OF OUR AREA MAY
ALLOW FOR SOME AFTERNOON CIRRUS AND MID DECK CLOUDS. SEA BREEZES ARE
LIKELY ALONG THE COAST BY THE AFTERNOON. TEMPS NEAR NORMAL TO A FEW
DEGREES BELOW NORMAL.
SUNDAY NIGHT THROUGH TUESDAY...MODERATE CONFIDENCE.
CLOUDS WILL CONTINUE TO INCREASE SUNDAY NIGHT AS A COLD FRONT MOVES
OUT OF N NY STATE AND NORTHERN NEW ENGLAND. THE FRONT WILL MOVE
SLOWLY TO THE SOUTHEAST...BUT LOOKS LIKE IT WILL REMAIN DRY THROUGH
AT LEAST MIDNIGHT. THE POTENTIAL EXISTS FOR A FEW SHOWERS LATE
SUNDAY NIGHT...MAINLY ACROSS N MA.
THE FRONT LOOKS TO SLOW ITS FORWARD PROGRESS AS IT BECOMES PARALLEL
TO THE UPPER LEVEL WIND FLOW DURING MONDAY. CONTINUE TO EXPECT A
COUPLE OF WAVES OF LOW PRES MOVE ALONG THE FRONT...WHICH WILL ALSO
TEND TO SLOW THE FRONT DOWN. STARTING TO SEE A BIT MORE MOISTURE
CONVERGENCE SETTING UP AS THE FRONT CROSSES...ESPECIALLY MONDAY
NIGHT AND TUESDAY...BRINGING SOME MUCH NEEDED RAINFALL.
FORECAST QPF AMOUNTS LOOK TO BE ON THE ORDER OF 0.5 TO 1 INCH FROM
MONDAY AFTERNOON INTO TUESDAY.
AS THE FRONT CROSSES THE REGION LATE MON NIGHT AND TUESDAY...
COOLER AIR WORKS IN AS WINDS SHIFT TO N AND NE. HIGHS WILL BE CLOSE
TO SEASONAL NORMALS ON MONDAY...BUT WILL FALL DOWN TO SEVERAL
DEGREES BELOW SEASONAL LEVELS ON TUESDAY.
TUESDAY NIGHT AND WEDNESDAY...MODERATE CONFIDENCE.
THE FRONT SHOULD PUSH SOUTH OF OUR AREA DURING TUESDAY NIGHT...WITH
CANADIAN HIGH PRESSURE BUILDING SOUTHEASTWARD. HAVE VERY LOW CHANCE
POPS TO START TUESDAY NIGHT. OTHERWISE EXPECT CLEARING SKIES
TUESDAY NIGHT.
FAST FLOW ALOFT WILL PUSH HIGH PRES ACROSS THE REGION ON
WEDNESDAY WITH DRY BUT COOL CONDITIONS. MOSTLY SUNNY SKIES FORECAST.
WEDNESDAY NIGHT THRU FRIDAY...LOW CONFIDENCE.
A LOT OF QUESTIONS REMAIN ON THE TIMING OF A FAST MOVING LOW
PRESSURE SYSTEM THAT IS EXPECTED TO AFFECT OUR AREA DURING
THISTIMEFRAME. AT THIS POINT HAVE DRY CONDITIONS FOR MOST OF WED
NIGHT...FOLLOWED BY CHANCE TO SLIGHT CHANCE POPS FOR SHOWERS THU
INTO FRI.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SATURDAY NIGHT/...
510 PM UDPATE...
THRU 23Z...MODERATE CONFIDENCE. SHOWERS AND ISOLATED T-STORMS
MOVING MAINLY W-E ACROSS SOUTHERN NEW ENGLAND...WITH THE BEST
CHANCE FOR T-STORMS WESTERN-CENTRAL MA AND NORTHERN CT. SOME OF
THE SHOWERS AND ESPECIALLY T-STORMS HAVE BEEN PRODUCING OUTFLOW
BOUNDARIES RESULTING IN ABRUPT AND SUBSTANTIAL WIND SHIFTS IN
VARIABLE DIRECTIONS. THIS WILL BE A RISK THRU 00Z. MAINLY VFR
CONDITIONS ACROSS THE AREA THRU 00Z...WITH LOCALIZED MVFR
CIGS/VSBYS WHERE MODERATE TO HEAVY RAINFALL OCCURS.
AFTER 23Z THIS EVENING...HIGH CONFIDENCE. GENERALLY VFR THROUGH
MIDNIGHT. SHOWERS AND A FEW THUNDERSTORMS THIS EVENING IN WESTERN
AND CENTRAL MASS AND NORTHERN CT. SOME SHOWERS MAY BRIEFLY LOWER
CIGS AND VSBYS TO MVFR.
TONIGHT...MODERATE CONFIDENCE. AFTER THE FIRST SET OF SHOWERS
DIMINISHES...A SECOND AREA OF SHOWERS WILL MOVE UP FROM THE
SOUTHWEST AFTER MIDNIGHT. EXPECT VFR CIGS TO LOWER TO MVFR
OVERNIGHT IN A FEW SHOWERS...WHILE SOUTH COASTAL NEW ENGLAND WILL
LOWER TO IFR OR LIFR IN SHOWERS AND DEVELOPING FOG.
SATURDAY AND SATURDAY NIGHT... HIGH CONFIDENCE. VFR CONDITIONS IN
THE WEST. CIGS/VSBYS IMPROVE TO VFR IN THE EAST. NORTH WIND AROUND
10 KNOTS WITH POTENTIAL GUSTS NEAR 20 KNOTS IN THE AFTERNOON.
WINDS DIMINISH TOWARD EVENING.
KBOS TERMINAL...MODERATE TO HIGH CONFIDENCE. EAST SEA BREEZE
SHOULD SWITCH TO SOUTH-SOUTHWEST BY LATE AFTERNOON. VFR CONDITIONS
SHOULD PERSIST THROUGH EARLY EVENING...BUT LEFTOVER SHOWERS FROM
WESTERN MASS MAY BRING BRIEF MVFR CIGS/VSBYS THIS EVENING. ANOTHER
AREA OF SHOWERS MOVES THROUGH LATER TONIGHT WITH MVFR CONDITIONS.
KBDL TERMINAL...MODERATE TO HIGH CONFIDENCE. MAINLY VFR. HOWEVER...BRIEF
LOWER CONDITIONS POSSIBLE THIS EVENING IN SCATTERED SHOWERS AND
PERHAPS A THUNDERSTORM. ALSO A PERIOD OF MVFR CIGS POSSIBLE
OVERNIGHT.
OUTLOOK /SUNDAY THROUGH WEDNESDAY/...
SUNDAY AND SUNDAY NIGHT...HIGH CONFIDENCE. VFR SUNDAY INTO SUNDAY
EVENING. MAY SEE MVFR CIGS/VSBYS MOVE INTO NORTHERN AREAS MAINLY
NEAR AND N OF THE MASS PIKE AFTER MIDNIGHT SUNDAY NIGHT.
MONDAY AND TUESDAY...MODERATE CONFIDENCE. AREAS OF MVFR
CIGS/VSBYS IN SHOWERS AND PATCHY FOG. CONDITIONS SHOULD IMPROVE
FROM N-S TUE NIGHT...THOUGH TIMING IS IN QUESTION.
WEDNESDAY...MODERATE CONFIDENCE. VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SATURDAY NIGHT/...
TONIGHT...MODERATE TO HIGH CONFIDENCE.
PERSISTENT SOUTHWEST FLOW AHEAD OF A COLD FRONT WILL REMAIN BELOW
20 KNOTS. THE PERSISTENT FLOW WILL BUILD SEAS A LITTLE WITH 5 FOOT
HEIGHTS ON THE OUTER WATERS SOUTH OF THE ISLANDS. SMALL CRAFT
ADVISORY CONTINUES ON THOSE WATERS. AREAS OF FOG DEVELOP DURING
THE NIGHT WHICH MAY BECOME LOCALLY DENSE...RESULTING IN POOR
VISIBILITY. WINDS WILL SHIFT LATER AT NIGHT AND COME FROM THE
NORTH OR NORTHWEST.
SATURDAY AND SATURDAY NIGHT...NORTH WINDS WITH GUSTS TO 20 KNOTS
SATURDAY AND 20 TO 25 KNOTS SATURDAY NIGHT. SEAS WILL BE 3-4 FEET
SATURDAY. HEIGHTS OF 4-6 FEET POSSIBLE ON THE EASTERN OUTER WATERS
SATURDAY NIGHT. A SMALL CRAFT ADVISORY MAY BE NEEDED ON SOME OF
THE WATERS.
OUTLOOK /SUNDAY THROUGH WEDNESDAY/...
SUNDAY...MODERATE CONFIDENCE. N WINDS VEERING TO THE SE ON SUNDAY.
GUSTS UP TO 25 KT POSSIBLE DURING THE MORNING...MAINLY ALONG THE
OUTER COASTAL WATERS. LINGERING 5 FOOT SEAS ON THE OUTER COASTAL
WATERS SHOULD GRADUALLY SUBSIDE DURING THE DAY.
MONDAY...MODERATE CONFIDENCE.
WINDS AND SEAS BELOW SCA THRESHOLDS. MAY SEE VSBY RESTRICTIONS IN
SCATTERED SHOWERS AND PATCHY FOG MONDAY.
MONDAY NIGHT AND TUESDAY...LOW TO MODERATE CONFIDENCE.
COLD FRONT SLOWLY MOVES FROM N TO S ACROSS THE WATERS. S WINDS
BECOME N DURING MON NIGHT/TUE. THEN THE N WINDS MAY GUST UP TO 20 KT
DURING TUE. SEAS BUILD UP TO 5-6 FT ACROSS THE SOUTHERN WATERS
MONDAY NIGHT AND TUESDAY...AND MAY REACH TO E OF CAPE COD DURING
TUESDAY. SHOULD HAVE SUBSIDING SEAS TUESDAY NIGHT. VSBY RESTRICTIONS
IN SHOWERS AND PATCHY FOG.
WEDNESDAY...MODERATE CONFIDENCE.
WINDS/SEAS BELOW SCA THRESHOLDS.
&&
.FIRE WEATHER...
SATURDAY...WIDELY SCATTERED SHOWERS MAY LINGER ACROSS SE MA/E RI
SATURDAY MORNING WITH N-NW WIND GUSTS UP TO 20 MPH. THESE SHOULD
PUSH OFFSHORE BY MIDDAY. DRY CONDITIONS WILL TAKE OVER SATURDAY
AFTERNOON WITH NORTH TO NORTHWEST WINDS USHERING LOWERING
DEWPOINTS. MINIMUM RELATIVE HUMIDITIES WILL BE FROM 25 TO 40
PERCENT NORTH AND WEST OF I-95 AND 40 TO 60 PERCENT TO THE SOUTH
AND EAST.
SUNDAY...HIGH PRESSURE WILL MOVE ACROSS THE REGION. LIGHT N WINDS AT
5 TO 10 MPH WILL BECOME SW DURING THE AFTERNOON...WITH SEA BREEZES
PROBABLE. MINIMUM RH VALUES WILL BE FROM 20 TO 30 PERCENT FOR MUCH
OF THE AREA...EXCEPT 35 TO 45 PERCENT ALONG THE IMMEDIATE COAST.
MONDAY AND TUESDAY...A SLOW MOVING FRONT COULD BRING A SOAKING
RAINFALL TO SOUTHERN NEW ENGLAND. THE BEST CHANCE FOR APPRECIABLE
RAIN IS MONDAY AFTERNOON THRU TUESDAY MORNING. AT THIS TIME THE
POTENTIAL EXISTS FOR 0.5 TO AROUND 1.0 INCH OF RAINFALL.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT SATURDAY FOR ANZ255-256.
&&
$$
SYNOPSIS...WTB/NMB
NEAR TERM...WTB/NMB
SHORT TERM...WTB
LONG TERM...NMB
AVIATION...WTB/NMB
MARINE...WTB/NMB
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS TAUNTON MA
418 PM EDT FRI APR 22 2016
.SYNOPSIS...
A COLD FRONT OVER NEW YORK CROSSES SOUTHERN NEW ENGLAND TONIGHT
AND MOVES OFFSHORE SATURDAY. HIGH PRESSURE THEN BUILDS FOR LATER
SATURDAY AND SUNDAY BRINGING DRY AND SEASONABLE WEATHER. A FRONT WILL
PUSH SLOWLY ACROSS THE REGION MONDAY AND TUESDAY WHICH WILL BRING
MUCH NEEDED SHOWERS TO THE REGION. DRY AND SEASONABLE CONDITIONS
SHOULD MOVE IN AROUND THE MIDDLE OF NEXT WEEK. THEN A LOW PRESSURE
SYSTEM MAY BRING ADDITIONAL RAINFALL TO OUR AREA THIS UPCOMING
THURSDAY AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
THIS EVENING/EARLY NIGHT...
NORTHERN STREAM SHORTWAVE AND SUPPORTING JET MOVE ACROSS NEW
ENGLAND THIS EVENING. FAVORABLE JET DYNAMICS ALONG WITH LI AROUND
-2 AND SBCAPE AROUND 1000 HAVE BEEN HELPING TO GENERATE SHOWERS
AND A FEW TSTMS OVER THE BERKSHIRES AND HUDSON VALLEY WHICH THEN
MOVE ACROSS WESTERN AND NORTHERN MASS. THESE FAVORABLE CONDITIONS
WILL FADE AFTER SUNSET...BUT UNTIL THEN EXPECT SHOWERS AND A FEW
TSTMS OVER WESTERN/NORTHERN MASS AND NORTHERN CT.
TONIGHT...
THE NEW YORK COLD FRONT EXTRAPOLATES TO THE BERKSHIRES 6-8
PM...THE WORCESTER HILLS 9-11 PM...AND THE EASTERN COAST 12-2 AM.
MEANWHILE...AN OPEN SHORTWAVE OVER OHIO IS MOVING EAST AND WILL
REACH THE MID ATLANTIC COAST BY SATURDAY MORNING. THE SHORTWAVE IS
SUPPORTED BY AN 85-KNOT JET THAT WILL OVERLAY NEW JERSEY AND LONG
ISLAND OVERNIGHT. THIS SHORTWAVE MAY TURN THE UPPER FLOW MORE
PARALLEL TO THE SURFACE COLD FRONT...SLOWING THE FORWARD PROGRESS
OF THAT FRONT. THE SHORTWAVE AND JET MAY ALSO GENERATE A WAVE
ALONG THE FRONT OVERNIGHT. BOTH THE GFS AND HRRR ARE HINTING AT
THIS. THE ECMWF SURFACE MSLP FIELD SHOWS A BAGGINESS SOUTH OF NEW
ENGLAND AT 12Z SAT THAT ALSO HINTS AT THIS.
DEW POINTS HAVE CLIMBED INTO THE 50S. WATER TEMPERATURES ARE IN
THE MID TO UPPER 40S. THIS COOLING OF THE MOIST AIR MAY CREATE
AREAS OF FOG THAT WOULD AFFECT THE SOUTH COAST.
WHILE THE EVENING PCPN TAPERS OFF...THE CHANCE OF SHOWERS ALONG
THE FRONT WILL LINGER UNTIL FROPA. THE UPPER SHORTWAVE AND JET
WILL MAINTAIN A CHANCE OF SHOWERS THROUGH THE NIGHT WITH THE BEST
CHANCE ALONG THE SOUTH COAST. WE WILL MAINTAIN CHANCE POPS THROUGH
THE NIGHT MOST PLACES AND CARRY LIKELY POPS ALONG/SOUTH OF A
HARTFORD-PROVIDENCE LINE. WITH DEW POINTS IN THE UPPER 40S AND
50S...EXPECT MIN TEMPS IN THIS SAME RANGE.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
UPPER TROUGH MOVES EAST OF NEW ENGLAND SATURDAY AND PUSHES THE
SURFACE FRONT WELL SOUTH OF OUR AREA. LEFTOVER SHOWERS...MAINLY
OVER RI/SOUTHEAST MASS...SHOULD MOVE OFF WITH THE TROUGH. HIGH
PRESSURE OVER CANADA WILL BUILD INTO NEW ENGLAND BRINGING DRIER
AIR AND CLEARING SKIES. MIXING IS FORECAST TO 900 MB...POSSIBLY A
LITTLE HIGHER. TEMPS AT THAT HEIGHT WOULD SUPPORT MAX SFC TEMPS IN
THE 60S. WINDS IN THE MIXED LAYER WILL BE 15-20 KNOTS...WHICH MAY
BE MIXED TO THE SURFACE IN GUSTS.
AS THE HIGH BUILDS IN...THE PRESSURE GRADIENT WILL LESSEN. NOT
CLEAR WHETHER IT WILL DIMINISH ENOUGH TO ALLOW THE SURFACE AIR TO
DECOUPLE AND ALLOW RADIATIONAL COOLING. DEW POINTS WILL FALL INTO
THE 20S...WHICH WOULD BE QUITE A CHILLY START TO THE DAY IF MINS
REACHED THAT LOW. WE WILL ALLOW A LIGHT NORTH WIND OVERNIGHT AND
KEEP TEMPS ABOVE FREEZING MOST PLACES. THE BEST CHANCE OF
DECOUPLING AND RADIATIONAL COOLING WILL BE IN THE VALLEYS OF
NORTHERN AND WESTERN MASS...WHERE THERE WILL BE THE BEST CHANCE OF
DIPPING BELOW 30. WE WILL NEED TO MONITOR THIS...SUCH COOLING MAY
BE ABLE TO EXTEND FARTHER SOUTH AND EAST.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
OVERVIEW...
LONG WAVE TROUGH ALONG THE EASTERN SEABOARD EARLY THIS WEEKEND
WILL SHIFT E AS OVERALL NORTH AMERICAN UPPER LEVEL STEERING
CURRENTS REMAIN PROGRESSIVE. BROAD H5 VORTEX ELONGATES FROM THE
ARCTIC CIRCLE INTO LABRADOR AND NEWFOUNDLAND BY SUNDAY...WITH THE
BASE OF THE VORTEX KEEPING A FAST W-NW UPPER FLOW ACROSS THE
REGION FOR MOST IF NOT ALL OF THE UPCOMING WEEK. THE NEXT
APPROACHING FRONT WILL MOVE INTO THE REGION BY THE BEGINNING OF
THE WORK WEEK AND...AS IT BECOMES PARALLEL TO THE UPPER FLOW...WILL
SEE MUCH NEEDED RAIN SHOWERS MOVE ACROSS AS THE FRONT SLOWLY PUSHES
OFFSHORE.
CANADIAN HIGH PRESSURE BRINGS DRY CONDITIONS WEDNESDAY. THEN LOW
CONFIDENCE ON THE TIMING AND TRACK AS A QUICK MOVING LOW PRESSURE
SYSTEM THAT SHOULD APPROACH THE REGION OUT OF THE OHIO VALLEY AND
SOUTHERN GREAT LAKES TOWARDS THE END OF THE UPCOMING WORKWEEK.
DETAILS...
SUNDAY...MODERATE TO HIGH CONFIDENCE.
HIGH PERSSURE PASSES OVERHEAD DURING THE DAY. ANTICIAPTE MOSTLY
SUNNY SKIES...THOUGH THE FRONT TO THE NORTHWEST OF OUR AREA MAY
ALLOW FOR SOME AFTERNOON CIRRUS AND MID DECK CLOUDS. SEA BREEZES ARE
LIKELY ALONG THE COAST BY THE AFTERNOON. TEMPS NEAR NORMAL TO A FEW
DEGREES BELOW NORMAL.
SUNDAY NIGHT THROUGH TUESDAY...MODERATE CONFIDENCE.
CLOUDS WILL CONTINUE TO INCREASE SUNDAY NIGHT AS A COLD FRONT MOVES
OUT OF N NY STATE AND NORTHERN NEW ENGLAND. THE FRONT WILL MOVE
SLOWLY TO THE SOUTHEAST...BUT LOOKS LIKE IT WILL REMAIN DRY THROUGH
AT LEAST MIDNIGHT. THE POTENTIAL EXISTS FOR A FEW SHOWERS LATE
SUNDAY NIGHT...MAINLY ACROSS N MA.
THE FRONT LOOKS TO SLOW ITS FORWARD PROGRESS AS IT BECOMES PARALLEL
TO THE UPPER LEVEL WIND FLOW DURING MONDAY. CONTINUE TO EXPECT A
COUPLE OF WAVES OF LOW PRES MOVE ALONG THE FRONT...WHICH WILL ALSO
TEND TO SLOW THE FRONT DOWN. STARTING TO SEE A BIT MORE MOISTURE
CONVERGENCE SETTING UP AS THE FRONT CROSSES...ESPECIALLY MONDAY
NIGHT AND TUESDAY...BRINGING SOME MUCH NEEDED RAINFALL.
FORECAST QPF AMOUNTS LOOK TO BE ON THE ORDER OF 0.5 TO 1 INCH FROM
MONDAY AFTERNOON INTO TUESDAY.
AS THE FRONT CROSSES THE REGION LATE MON NIGHT AND TUESDAY...
COOLER AIR WORKS IN AS WINDS SHIFT TO N AND NE. HIGHS WILL BE CLOSE
TO SEASONAL NORMALS ON MONDAY...BUT WILL FALL DOWN TO SEVERAL
DEGREES BELOW SEASONAL LEVELS ON TUESDAY.
TUESDAY NIGHT AND WEDNESDAY...MODERATE CONFIDENCE.
THE FRONT SHOULD PUSH SOUTH OF OUR AREA DURING TUESDAY NIGHT...WITH
CANADIAN HIGH PRESSURE BUILDING SOUTHEASTWARD. HAVE VERY LOW CHANCE
POPS TO START TUESDAY NIGHT. OTHERWISE EXPECT CLEARING SKIES
TUESDAY NIGHT.
FAST FLOW ALOFT WILL PUSH HIGH PRES ACROSS THE REGION ON
WEDNESDAY WITH DRY BUT COOL CONDITIONS. MOSTLY SUNNY SKIES FORECAST.
WEDNESDAY NIGHT THRU FRIDAY...LOW CONFIDENCE.
A LOT OF QUESTIONS REMAIN ON THE TIMING OF A FAST MOVING LOW
PRESSURE SYSTEM THAT IS EXPECTED TO AFFECT OUR AREA DURING
THISTIMEFRAME. AT THIS POINT HAVE DRY CONDITIONS FOR MOST OF WED
NIGHT...FOLLOWED BY CHANCE TO SLIGHT CHANCE POPS FOR SHOWERS THU
INTO FRI.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SATURDAY NIGHT/...
THIS EVENING... HIGH CONFIDENCE. GENERALLY VFR THROUGH MIDNIGHT.
SHOWERS AND A FEW THUNDERSTORMS THIS EVENING IN WESTERN AND
CENTRAL MASS AND NORTHERN CT. SOME SHOWERS MAY BRIEFLY LOWER CIGS
AND VSBYS TO MVFR.
TONIGHT...MODERATE CONFIDENCE. AFTER THE FIRST SET OF SHOWERS
DIMINISHES...A SECOND AREA OF SHOWERS WILL MOVE UP FROM THE
SOUTHWEST AFTER MIDNIGHT. EXPECT VFR CIGS TO LOWER TO MVFR
OVERNIGHT IN A FEW SHOWERS...WHILE SOUTH COASTAL NEW ENGLAND WILL
LOWER TO IFR OR LIFR IN SHOWERS AND DEVELOPING FOG.
SATURDAY AND SATURDAY NIGHT... HIGH CONFIDENCE. VFR CONDITIONS IN
THE WEST. CIGS/VSBYS IMPROVE TO VFR IN THE EAST. NORTH WIND AROUND
10 KNOTS WITH POTENTIAL GUSTS NEAR 20 KNOTS IN THE AFTERNOON.
WINDS DIMINISH TOWARD EVENING.
KBOS TERMINAL...MODERATE TO HIGH CONFIDENCE. EAST SEA BREEZE
SHOULD SWITCH TO SOUTH-SOUTHWEST BY LATE AFTERNOON. VFR CONDITIONS
SHOULD PERSIST THROUGH EARLY EVENING...BUT LEFTOVER SHOWERS FROM
WESTERN MASS MAY BRING BRIEF MVFR CIGS/VSBYS THIS EVENING. ANOTHER
AREA OF SHOWERS MOVES THROUGH LATER TONIGHT WITH MVFR CONDITIONS.
KBDL TERMINAL...MODERATE TO HIGH CONFIDENCE. MAINLY VFR. HOWEVER...BRIEF
LOWER CONDITIONS POSSIBLE THIS EVENING IN SCATTERED SHOWERS AND
PERHAPS A THUNDERSTORM. ALSO A PERIOD OF MVFR CIGS POSSIBLE
OVERNIGHT.
OUTLOOK /SUNDAY THROUGH WEDNESDAY/...
SUNDAY AND SUNDAY NIGHT...HIGH CONFIDENCE. VFR SUNDAY INTO SUNDAY
EVENING. MAY SEE MVFR CIGS/VSBYS MOVE INTO NORTHERN AREAS MAINLY
NEAR AND N OF THE MASS PIKE AFTER MIDNIGHT SUNDAY NIGHT.
MONDAY AND TUESDAY...MODERATE CONFIDENCE. AREAS OF MVFR
CIGS/VSBYS IN SHOWERS AND PATCHY FOG. CONDITIONS SHOULD IMPROVE
FROM N-S TUE NIGHT...THOUGH TIMING IS IN QUESTION.
WEDNESDAY...MODERATE CONFIDENCE. VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SATURDAY NIGHT/...
TONIGHT...MODERATE TO HIGH CONFIDENCE.
PERSISTENT SOUTHWEST FLOW AHEAD OF A COLD FRONT WILL REMAIN BELOW
20 KNOTS. THE PERSISTENT FLOW WILL BUILD SEAS A LITTLE WITH 5 FOOT
HEIGHTS ON THE OUTER WATERS SOUTH OF THE ISLANDS. SMALL CRAFT
ADVISORY CONTINUES ON THOSE WATERS. AREAS OF FOG DEVELOP DURING
THE NIGHT WHICH MAY BECOME LOCALLY DENSE...RESULTING IN POOR
VISIBILITY. WINDS WILL SHIFT LATER AT NIGHT AND COME FROM THE
NORTH OR NORTHWEST.
SATURDAY AND SATURDAY NIGHT...NORTH WINDS WITH GUSTS TO 20 KNOTS
SATURDAY AND 20 TO 25 KNOTS SATURDAY NIGHT. SEAS WILL BE 3-4 FEET
SATURDAY. HEIGHTS OF 4-6 FEET POSSIBLE ON THE EASTERN OUTER WATERS
SATURDAY NIGHT. A SMALL CRAFT ADVISORY MAY BE NEEDED ON SOME OF
THE WATERS.
OUTLOOK /SUNDAY THROUGH WEDNESDAY/...
SUNDAY...MODERATE CONFIDENCE. N WINDS VEERING TO THE SE ON SUNDAY.
GUSTS UP TO 25 KT POSSIBLE DURING THE MORNING...MAINLY ALONG THE
OUTER COASTAL WATERS. LINGERING 5 FOOT SEAS ON THE OUTER COASTAL
WATERS SHOULD GRADUALLY SUBSIDE DURING THE DAY.
MONDAY...MODERATE CONFIDENCE.
WINDS AND SEAS BELOW SCA THRESHOLDS. MAY SEE VSBY RESTRICTIONS IN
SCATTERED SHOWERS AND PATCHY FOG MONDAY.
MONDAY NIGHT AND TUESDAY...LOW TO MODERATE CONFIDENCE.
COLD FRONT SLOWLY MOVES FROM N TO S ACROSS THE WATERS. S WINDS
BECOME N DURING MON NIGHT/TUE. THEN THE N WINDS MAY GUST UP TO 20 KT
DURING TUE. SEAS BUILD UP TO 5-6 FT ACROSS THE SOUTHERN WATERS
MONDAY NIGHT AND TUESDAY...AND MAY REACH TO E OF CAPE COD DURING
TUESDAY. SHOULD HAVE SUBSIDING SEAS TUESDAY NIGHT. VSBY RESTRICTIONS
IN SHOWERS AND PATCHY FOG.
WEDNESDAY...MODERATE CONFIDENCE.
WINDS/SEAS BELOW SCA THRESHOLDS.
&&
.FIRE WEATHER...
SATURDAY...WIDELY SCATTERED SHOWERS MAY LINGER ACROSS SE MA/E RI
SATURDAY MORNING WITH N-NW WIND GUSTS UP TO 20 MPH. THESE SHOULD
PUSH OFFSHORE BY MIDDAY. DRY CONDITIONS WILL TAKE OVER SATURDAY
AFTERNOON WITH NORTH TO NORTHWEST WINDS USHERING LOWERING
DEWPOINTS. MINIMUM RELATIVE HUMIDITIES WILL BE FROM 25 TO 40
PERCENT NORTH AND WEST OF I-95 AND 40 TO 60 PERCENT TO THE SOUTH
AND EAST.
SUNDAY...HIGH PRESSURE WILL MOVE ACROSS THE REGION. LIGHT N WINDS AT
5 TO 10 MPH WILL BECOME SW DURING THE AFTERNOON...WITH SEA BREEZES
PROBABLE. MINIMUM RH VALUES WILL BE FROM 20 TO 30 PERCENT FOR MUCH
OF THE AREA...EXCEPT 35 TO 45 PERCENT ALONG THE IMMEDIATE COAST.
MONDAY AND TUESDAY...A SLOW MOVING FRONT COULD BRING A SOAKING
RAINFALL TO SOUTHERN NEW ENGLAND. THE BEST CHANCE FOR APPRECIABLE
RAIN IS MONDAY AFTERNOON THRU TUESDAY MORNING. AT THIS TIME THE
POTENTIAL EXISTS FOR 0.5 TO AROUND 1.0 INCH OF RAINFALL.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EDT SATURDAY FOR ANZ255-256.
&&
$$
SYNOPSIS...WTB/EVT
NEAR TERM...WTB/EVT
SHORT TERM...WTB
LONG TERM...EVT
AVIATION...WTB/EVT
MARINE...WTB/EVT
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
141 PM EDT FRI APR 22 2016
.Aviation...
[Through 18Z Saturday] Numerous SHRA and isolated TSRA will
continue to affect south GA, southeast AL, and the FL Panhandle
and Big Bend this afternoon. The rain will end this evening, but
low clouds and fog (IFR) will develop later tonight across much of
the region. A cold front will pass through the area Saturday
morning, eventually clearing the clouds and fog late in the
morning.
&&
.Prev Discussion [909 AM EDT]...
.Near Term [Through Today]...
The 7 am EDT regional surface analysis showed a cold front from
northeast MS to the coastal waters of TX. Vapor imagery and upper
air data showed a positive-tilted trough approaching from the
west. There was an MCS propagating eastward across the FL
Panhandle and Southeast AL, which the latest HRRR appears to have
initialized fairly well. This system is expected to weaken a bit
as it moves into a region with less favorable thermodynamics, but
we are still forecasting high rain chances across most of our area
this afternoon given the expected Q-G forcing and moisture ahead
of the approaching trough. Forecast max MLCAPE values will be
around 1000 J/kg, and 0-6 km bulk shear values will be in the
20-30 KT range. These levels are marginal for storm
organization/strong updrafts, but we can`t rule out a marginally
damaging wind gust.
.Short Term [Tonight Through Sunday]...
The frontal boundary will be clearing the area tonight with
showers and thunderstorms rapidly decreasing after sunset.
Thereafter, dry conditions will prevail through the weekend with
temperatures near to slightly above average, generally low to mid
80s for highs and upper 50s to lower 60s for lows.
.Long Term [Sunday Night Through Friday]...
A rather dry and warm pattern will dominate through next week with
weak upper level ridging in place over the southeast. Expect to
see highs in the lower to mid 80s with lows in the 60s throughout
the period.
.Marine...
Generally light winds will shift to the northwest tonight behind a
cold frontal passage. Winds and seas are expected to remain on
the low side through early next week. A sea breeze is possible
near the coast on Saturday afternoon as well as Sunday afternoon.
.Fire Weather...
Aside from high dispersion values Saturday, there are no fire
weather concerns at least for the next several days.
.Hydrology...
Steady or falling river levels are expected through this weekend.
Rainfall amounts with today`s frontal system are expected to
average generally less than 1 inch for most areas with no
significant impacts on area rivers.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 62 85 58 87 61 / 10 0 0 0 0
Panama City 65 79 63 80 64 / 10 0 0 0 0
Dothan 58 82 57 85 60 / 30 0 0 0 0
Albany 58 83 57 84 60 / 40 0 0 0 0
Valdosta 61 86 58 88 60 / 30 0 0 0 0
Cross City 63 84 59 86 61 / 10 0 0 0 0
Apalachicola 64 80 62 79 64 / 10 0 0 0 0
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AL...NONE.
GM...NONE.
&&
$$
NEAR TERM...FOURNIER
SHORT TERM...DVD
LONG TERM...DVD
AVIATION...FOURNIER
MARINE...DVD
FIRE WEATHER...BARRY
HYDROLOGY...DVD
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
909 AM EDT FRI APR 22 2016
.Near Term [Through Today]...
The 7 am EDT regional surface analysis showed a cold front from
northeast MS to the coastal waters of TX. Vapor imagery and upper
air data showed a positive-tilted trough approaching from the
west. There was an MCS propagating eastward across the FL
Panhandle and Southeast AL, which the latest HRRR appears to have
initialized fairly well. This system is expected to weaken a bit
as it moves into a region with less favorable thermodynamics, but
we are still forecasting high rain chances across most of our area
this afternoon given the expected Q-G forcing and moisture ahead
of the approaching trough. Forecast max MLCAPE values will be
around 1000 J/kg, and 0-6 km bulk shear values will be in the
20-30 KT range. These levels are marginal for storm
organization/strong updrafts, but we can`t rule out a marginally
damaging wind gust.
&&
.Prev Discussion [635 AM EDT]...
.Short Term [Tonight Through Sunday]...
The frontal boundary will be clearing the area tonight with
showers and thunderstorms rapidly decreasing after sunset.
Thereafter, dry conditions will prevail through the weekend with
temperatures near to slightly above average, generally low to mid
80s for highs and upper 50s to lower 60s for lows.
.Long Term [Sunday Night Through Friday]...
A rather dry and warm pattern will dominate through next week with
weak upper level ridging in place over the southeast. Expect to
see highs in the lower to mid 80s with lows in the 60s throughout
the period.
.Aviation...
[Through 12Z Saturday] MVFR vis and/or ceilings will continue at
most TAF sites until shortly after daybreak. Otherwise, an area
of showers and thunderstorms will spread from west to east
impacting all terminals today. Convection will begin at ECP and
DHN around 12z, TLH and ABY between 17z and 18z, and VLD around
19z.
.Marine...
Generally light winds will shift to the northwest tonight behind a
cold frontal passage. Winds and seas are expected to remain on
the low side through early next week. A sea breeze is possible
near the coast on Saturday afternoon as well as Sunday afternoon.
.Fire Weather...
Aside from high dispersion values Saturday, there are no fire
weather concerns at least for the next several days.
.Hydrology...
Steady or falling river levels are expected through this weekend.
Rainfall amounts with today`s frontal system are expected to
average generally less than 1 inch for most areas with no
significant impacts on area rivers.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 82 62 85 59 86 / 70 10 10 0 0
Panama City 79 65 77 63 78 / 100 10 10 0 0
Dothan 80 58 81 57 82 / 100 30 0 0 0
Albany 79 58 81 58 83 / 80 40 0 0 0
Valdosta 83 61 83 58 83 / 70 30 10 0 0
Cross City 81 63 82 57 85 / 40 10 10 0 0
Apalachicola 80 64 80 61 78 / 60 10 10 0 0
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AL...NONE.
GM...NONE.
&&
$$
NEAR TERM...FOURNIER
SHORT TERM...DVD
LONG TERM...DVD
AVIATION...BARRY
MARINE...DVD
FIRE WEATHER...BARRY
HYDROLOGY...DVD
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
322 PM EDT FRI APR 22 2016
.SHORT TERM /TONIGHT THROUGH SUNDAY/...
CONVECTION CONTINUES TO INCREASE ACROSS AL...ERN TN AND NW GA. SO
FAR NOTHING TOO BAD WITH A COUPLE SIG WX ADVISORIES ISSUED OVER
NRN AL. CURRENT TEMPS STILL IN THE UPPER 60S TO AROUND 70 AND
DEWPOINTS AROUND 60. RESULTING SBCAPE OVER ERN AL AND FAR NW GA
STILL LIMITED TO 500-1000 J/KG AND VERTICAL WIND SHEAR QUITE WEAK.
LOW END DAMAGING WIND AND SMALL HAIL THREAT APPEARS TO BE IN LINE
WITH SPC MARGINAL RISK BUT WILL CONTINUE TO MONITOR.
EXPECT ISOLD TO SCT /20-40PCT/ COVERAGE OF STORMS REST OF
AFTERNOON THRU 10 PM OR SO TONIGHT BEFORE DIMINISHING. SO POPS
APPEAR OK. ALL PRECIP SHOULD BE OUT OF CWA BY MIDNIGHT.
NO FCST PROBLEMS EXPECTED THRU REST OF SHORT TERM FCST PERIOD.
IF WINDS DIE DOWN TONIGHT...AS SOME MOS FORECASTS INDICATE...COULD
SEE PATCHY GROUND FOG.
TEMPERATURES NEAR OR ABOVE NORMAL THIS WEEKEND. BLEND
INCORPORATING BIAS CORRECTION AND RECENT PERFORMANCE GENERALLY
ACCEPTED.
SNELSON
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
NLISTEMAA
NO MAJOR CHANGES TO THE LONG TERM PORTION OF THE FORECAST WERE
NEEDED. TWO SYSTEMS ARE EXPECTED TO IMPACT THE CWFA...ONE DURING THE
MIDDLE PART OF THE WEEK WITH THE NEXT SYSTEM EXPECTED FOR FRIDAY
INTO THE EARLY WEEKEND.
HIGH PRESSURE WILL REMAIN ACROSS THE WESTERN ATLANTIC THROUGH
TUESDAY. HOWEVER, THE HIGH CENTER WILL GET SHIFTED TO THE SOUTH AND
EAST BY LATE TUESDAY/EARLY WEDNESDAY AS A FRONTAL BOUNDARY
APPROACHES FROM THE NORTH. THE 500MB FLOW WILL REMAIN ZONAL THROUGH
THROUGH THE END OF THE WEEK...SO THE BOUNDARY SHOULD NOT MAKE IT TOO
FAR INTO THE NORTHERN CWFA BEFORE STALLING. THE HIGHEST POPS FOR THE
MIDDLE PART OF THE WEEK SHOULD BE IN THE VICINITY OF THIS BOUNDARY.
CURRENTLY...THE LONG TERM MODELS HAVE THE NEXT BOUNDARY IMPACTING
THE CWFA ON FRIDAY INTO EARLY SATURDAY.
NLISTEMAA
PREV LONG TERM DISCUSSION /SATURDAY NIGHT THROUGH THURSDAY/...
/ISSUED 344 AM EDT FRI APR 22 2016/
LONG TERM PERIOD BEGINS WITH LAST OF THE SHORTWAVE ENERGY EXITING
EAST AND TAKING ALL OF THE DEEP LAYER MOISTURE WITH IT. WITH
TIME...THROUGH SUNDAY...THE TROUGH WILL BE REPLACED BY AND UPPER
LEVEL RIDGE PROVIDING FOR A DRY PATTERN AND INCREASING
TEMPERATURES. BY SUNDAY AFTERNOON...MOST LOCATIONS WILL BE
APPROACHING THE 80 DEGREE MARK ONCE AGAIN WHICH WILL BE SOME 3 TO
5 DEGREES ABOVE SAT VALUES.
A FAIRLY STAGNANT PATTERN IN STORE THROUGH MONDAY NIGHT AS UPPER
RIDGE DOMINATES FOR MOST OF THE PERIOD BUT DOES BREAK DOWN INTO
MORE OF A ZONAL FLOW BY TUE MORNING. SURFACE RIDGE WILL GRADUALLY
SHIFT FROM THE CAROLINAS TO WELL OFFSHORE WHICH WILL PROMOTE MORE
OF A MOIST SOUTHERLY FLOW ACROSS THE AREA. IMPULSES MOVING QUICKLY
ACROSS THE SOUTH WILL EVENTUALLY IMPACT PORTIONS OF NORTH GEORGIA
TUESDAY AFTERNOON. MOISTURE WILL CONTINUE TO BE LIMITED BUT ENOUGH
LIFT AND INSTABILITY PRESENT TO WARRANT LOW END CHANCE POPS ACROSS
THE FAR NORTHERN TIER.
WILL CONTINUE WITH THE MAINLY DIURNAL CONVECTION AND LOW END
CHANCE POPS ACROSS THE FAR NORTH THROUGH WED. THEREAFTER...A COLD
FRONT WILL SAG INTO THE STATE WITH INCREASED DEEP LAYER MOISTURE.
FRONT HOWEVER STALLS QUICKLY AS UPPER RIDGE BUILDS BACK IN AND
MOISTURE LESSENS. SOME INDICATIONS FOR LATE FRI INTO NEXT WEEKEND
OF POTENTIAL NW FLOW STORMS BUT OVERALL A BENIGN PATTERN FOR MID
SPRING.
DEESE
&&
.PREV DISCUSSION... /ISSUED 228 PM EDT FRI APR 22 2016/
UPDATE...
ALREADY DID TWEAKS TO NEAR TERM POP...WX AND SKY GRIDS BASED ON
RADAR TRENDS. HIRES MODELS AND HRRR DOING A DECENT JOB HANDLING
THE RAIN BAND AND NOW DEVELOPING ISOLD CONVECTION IN ERN AL...NW
GA AND CENTRAL/ERN TN. INSTABILITY INCREASING IN ERN AL BUT NOT
AS MUCH AS FEARED EVEN THOUGH TEMPS AROUND 80F IN COUNTIES SOUTH
AND EAST OF RAIN AREA IN EC GA. ANY STORMS THAT DEVELOP OVER NW GA
THIS AFTERNOON COULD HAVE SOME STRONG WINDS AND SMALL HAIL THREAT.
SNELSON
&&
AVIATION...
18Z UPDATE...
SEVERAL ISSUES WITH FORECAST...IFR CIGS FINALLY DISSIPATING IN
RAIN AREA. STUBBORN TO CLEAR OUT OF KCSG BUT MOST OTHER AREAS MVFR
OR VFR AT THIS TIME. SFC WINDS MOSTLY SW BUT MAY BRIEFLY SWITCH TO
SE ON BACK SIDE OF RAIN AREA MOVING THROUGH. ISOLD TSRA EXPECTED
TO INCREASE OVER NW 1/2 OF GA THRU 23Z. EXPECTED COVERAGE JUST
ENOUGH TO WARRANT TEMPO FOR 21-24Z AT ATL METRO AIRPORTS. RAPID
CLEARING EXPECTED AFTER 02Z BUT COULD SEE PATCH GROUND FOG AFTER
10Z WHERE WINDS GO CALM AND PREVIOUS RAINFALL SLOW TO EVAPORATE.
SFC WINDS WILL REMAIN ON WEST COMPONENT THRU FCST. NO SIGNIFICANT GUSTS
EXPECTED.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE ON TSRA LIKELIHOOD AND LOCATIONS.
MEDIUM CONFIDENCE ON FOG OVERNIGHT.
HIGH CONFIDENCE ON ALL OTHER ELEMENTS.
SNELSON
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 55 78 54 79 / 40 0 0 0
ATLANTA 56 75 56 78 / 40 0 0 0
BLAIRSVILLE 52 72 49 76 / 50 0 0 0
CARTERSVILLE 53 74 51 79 / 30 0 0 0
COLUMBUS 57 77 56 81 / 40 0 0 0
GAINESVILLE 55 75 54 77 / 40 0 0 0
MACON 57 78 55 81 / 40 0 0 0
ROME 54 75 51 79 / 30 0 0 0
PEACHTREE CITY 53 76 52 79 / 50 0 0 0
VIDALIA 62 80 59 82 / 40 5 0 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SNELSON
LONG TERM....NLISTEMAA
AVIATION...SNELSON
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
228 PM EDT FRI APR 22 2016
.UPDATE...
ALREADY DID TWEAKS TO NEAR TERM POP...WX AND SKY GRIDS BASED ON
RADAR TRENDS. HIRES MODELS AND HRRR DOING A DECENT JOB HANDLING
THE RAIN BAND AND NOW DEVELOPING ISOLD CONVECTION IN ERN AL...NW
GA AND CENTRAL/ERN TN. INSTABILITY INCREASING IN ERN AL BUT NOT
AS MUCH AS FEARED EVEN THOUGH TEMPS AROUND 80F IN COUNTIES SOUTH
AND EAST OF RAIN AREA IN EC GA. ANY STORMS THAT DEVELOP OVER NW GA
THIS AFTERNOON COULD HAVE SOME STRONG WINDS AND SMALL HAIL THREAT.
SNELSON
&&
.PREV DISCUSSION... /ISSUED 803 AM EDT FRI APR 22 2016/
SHORT TERM /TODAY THROUGH SATURDAY/...
NEAR TERM MAINLY WITH PRE-FRONTAL MIDLEVEL WAVE OF MOISTURE ALLOWING
FOR SCATTERED SHOWERS PUSHING ACROSS PORTIONS OF NORTH GEORGIA EARLY
THIS MORNING...THOUGH GREATEST CHANCE WILL BE THIS AFTERNOON INTO
EVENING AHEAD AND ALONG RATHER HIGH AMPLITUDE UPPER SHORTWAVE TROUGH
AND TRANSLATED SFC FROPA. HAVE TRENDED LIKELY POPS ACCORDINGLY WITH
GREATEST CHANCE CENTERED IN THE 15-21Z WINDOW. PROGGED CAPE VALUES
LOOK TO INCREASE ENOUGH FOR GENERAL CHANCE THUNDER THOUGH LOOK TO
REMAIN BELOW 1000 J/KG EVEN WITH THE MU PARCEL. ANY LINGERING CLOUD
COVERAGE AHEAD OF SYSTEM MAY ALSO SERVE TO LIMIT DESTABILIZATION...
THOUGH WILL HAVE MARGINAL DEEP LAYER SHEAR NEAR 30-35 KTS AND RATHER
LOW FRZING LEVEL WITH DECENT LOW LEVEL LAPSE RATES SO SOME STRONG
STORMS...POSSIBLY LOW END SEVERE COULD DEVELOP. GUSTY
WINDS...HAIL...AND FREQUENT LIGHTNING WOULD BE MAIN THREATS THIS
AFTERNOON WITH STRONGER CONVECTION. OTHERWISE LOOKING TO HAVE
CLEARING SKIES OVERNIGHT TONIGHT WITH UPPER RIDGING AND POST-FRONTAL
REGIME. ENHANCED GRADIENT NW WINDS ON TAP FOR SATURDAY WITH DRY
CONDITIONS.
TEMPS SHOULD STAY SLIGHTLY BELOW NORMAL TODAY THEN ACTUALLY A BIT
WARMER CLOSER TO OR SLIGHTLY ABOVE NORMAL FOR SATURDAY WITH DECENT
DIURNAL HEATING DESPITE THE FROPA.
BAKER
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
LONG TERM PERIOD BEGINS WITH LAST OF THE SHORTWAVE ENERGY EXITING
EAST AND TAKING ALL OF THE DEEP LAYER MOISTURE WITH IT. WITH
TIME...THROUGH SUNDAY...THE TROUGH WILL BE REPLACED BY AND UPPER
LEVEL RIDGE PROVIDING FOR A DRY PATTERN AND INCREASING
TEMPERATURES. BY SUNDAY AFTERNOON...MOST LOCATIONS WILL BE
APPROACHING THE 80 DEGREE MARK ONCE AGAIN WHICH WILL BE SOME 3 TO
5 DEGREES ABOVE SAT VALUES.
A FAIRLY STAGNANT PATTERN IN STORE THROUGH MONDAY NIGHT AS UPPER
RIDGE DOMINATES FOR MOST OF THE PERIOD BUT DOES BREAK DOWN INTO
MORE OF A ZONAL FLOW BY TUE MORNING. SURFACE RIDGE WILL GRADUALLY
SHIFT FROM THE CAROLINAS TO WELL OFFSHORE WHICH WILL PROMOTE MORE
OF A MOIST SOUTHERLY FLOW ACROSS THE AREA. IMPULSES MOVING QUICKLY
ACROSS THE SOUTH WILL EVENTUALLY IMPACT PORTIONS OF NORTH GEORGIA
TUESDAY AFTERNOON. MOISTURE WILL CONTINUE TO BE LIMITED BUT ENOUGH
LIFT AND INSTABILITY PRESENT TO WARRANT LOW END CHANCE POPS ACROSS
THE FAR NORTHERN TIER.
WILL CONTINUE WITH THE MAINLY DIURNAL CONVECTION AND LOW END
CHANCE POPS ACROSS THE FAR NORTH THROUGH WED. THEREAFTER...A COLD
FRONT WILL SAG INTO THE STATE WITH INCREASED DEEP LAYER MOISTURE.
FRONT HOWEVER STALLS QUICKLY AS UPPER RIDGE BUILDS BACK IN AND
MOISTURE LESSENS. SOME INDICATIONS FOR LATE FRI INTO NEXT WEEKEND
OF POTENTIAL NW FLOW STORMS BUT OVERALL A BENIGN PATTERN FOR MID
SPRING.
DEESE
&&
.AVIATION...
18Z UPDATE...
SEVERAL ISSUES WITH FORECAST...IFR CIGS FINALLY DISSIPATING IN
RAIN AREA. STUBBORN TO CLEAR OUT OF KCSG BUT MOST OTHER AREAS MVFR
OR VFR AT THIS TIME. SFC WINDS MOSTLY SW BUT MAY BRIEFLY SWITCH TO
SE ON BACK SIDE OF RAIN AREA MOVING THROUGH. ISOLD TSRA EXPECTED
TO INCREASE OVER NW 1/2 OF GA THRU 23Z. EXPECTED COVERAGE JUST
ENOUGH TO WARRANT TEMPO FOR 21-24Z AT ATL METRO AIRPORTS. RAPID
CLEARING EXPECTED AFTER 02Z BUT COULD SEE PATCH GROUND FOG AFTER
10Z WHERE WINDS GO CALM AND PREVIOUS RAINFALL SLOW TO EVAPORATE.
SFC WINDS WILL REMAIN ON WEST COMPONENT THRU FCST. NO SIGNIFICANT GUSTS
EXPECTED.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE ON TSRA LIKELIHOOD AND LOCATIONS.
MEDIUM CONFIDENCE ON FOG OVERNIGHT.
HIGH CONFIDENCE ON ALL OTHER ELEMENTS.
SNELSON
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 72 55 78 55 / 70 40 0 0
ATLANTA 71 56 76 57 / 80 20 0 0
BLAIRSVILLE 67 51 73 50 / 80 30 0 0
CARTERSVILLE 72 52 75 51 / 70 20 0 0
COLUMBUS 74 57 78 55 / 80 30 0 0
GAINESVILLE 69 55 75 55 / 90 30 0 0
MACON 77 57 78 54 / 70 40 0 0
ROME 74 53 75 51 / 60 20 0 0
PEACHTREE CITY 72 53 76 52 / 80 30 0 0
VIDALIA 82 61 80 58 / 70 50 0 0
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SNELSON
LONG TERM....NLISTEMAA
AVIATION...SNELSON
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
131 AM EDT FRI APR 22 2016
.SYNOPSIS...
SURFACE HIGH PRESSURE OFF THE COAST WILL CIRCULATE A MOIST
SOUTHERLY FLOW INTO THE FORECAST AREA AHEAD OF AN APPROACHING COLD
FRONT. THE FRONT WILL CROSS THE AREA FRIDAY NIGHT. SHOWERS AND
THUNDERSTORMS ARE EXPECTED AHEAD OF THE FRONT FRIDAY. DRY HIGH
PRESSURE WILL BUILD INTO THE REGION LATE SATURDAY THROUGH TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
MOISTURE WILL BE ON THE INCREASE IN THE SOUTHERLY FLOW WELL AHEAD
OF THE COLD FRONT TONIGHT. RADAR TRENDS AND THE HRRR SUPPORT
SCATTERED SHOWERS IN THE FORECAST AREA MAINLY AFTER 200 AM.
OBSERVATION TRENDS SUPPORT THE MODEL FORECAST OF INSTABILITY
REMAINING WEAK OVERNIGHT. THE THUNDERSTORM CHANCE IS LOW.
CLOUDINESS AND MIXING SHOULD HELP HOLD UP TEMPERATURES. EXPECT
LOWS MAINLY IN THE LOWER 60S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
MOST PLACES LOOK TO GET WET ON FRIDAY AS A MODERATE STRENGTH UPPER
TROF AND ASSOCIATED COLD FRONT APPROACHES FROM THE WEST. DEEP
MOISTURE FLOW AHEAD OF THE SYSTEM SHOULD RAISE PWS TO AROUND 1.5
INCHES ACROSS THE CWA...AND DECENT LIFT DUE TO DIFFERENTIAL
VORTICITY ADVECTION IN MID LEVELS AND UPPER LEVEL JET DIVERGENCE
WILL PRODUCE WIDESPREAD SHOWERS WITH A FEW THUNDERSTORMS. THERE
WILL BE SOME MODEST LOW LEVEL CAPE WITH VALUES POTENTIALLY AS HIGH
AS 1000 J/KG...BUT DEEP LAYERED SHEAR IS NOT TOO IMPRESSIVE...SO
THE THREAT FOR SEVERE WEATHER LOOKS LOW. QPF WILL GENERALLY BE 1/2
INCH OR LESS...BUT PLACES THAT DO SEE SOME THUNDERSTORMS...
ESPECIALLY IN THE SOUTHEASTERN THIRD OF THE CWA...COULD GET
LOCALLY UP TO AN INCH. TEMPS SHOULD BE SEASONABLY WARM IN THE
UPPER 70S DESPITE CLOUD COVER AS THERE WILL BE LOW LEVEL WARM
ADVECTION AHEAD OF THE COLD FRONT.
FRIDAY NIGHT...THE BEST OF THE UPPER SUPPORT SHOULD MOVE THROUGH
QUICKLY...AS WILL THE COLD FRONT. SHOWERS WILL END FROM WEST TO
EAST DURING THE EVENING...WITH JUST A FEW LINGERING IN THE
SOUTHEAST AFTER MIDNIGHT. TEMPS WILL DROP DOWN INTO THE UPPER
50S...NOT PARTICULARLY COOL AS CLOUDS WILL NOT CLEAR UNTIL LATE
AND WINDS WILL REMAIN UP.
SATURDAY SHOULD BE MOSTLY DRY AS THE FRONT MOVES OFFSHORE. I CANT
RULE OUT A SHOWER IN THE NORTHEAST AS ANOTHER SPOKE OF ENERGY
DROPS INTO NORTH CAROLINA...BUT CHANCES LOOK TOO LOW AT THIS TIME
TO MENTION IN THE FORECAST. TEMPS WILL BE SEASONABLE WITH MID 70S
NORTH TO NEAR 80 IN THE CSRA.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
A SURFACE AREA OF HIGH PRESSURE WILL MOVE INTO THE SOUTHEAST FROM
SUNDAY INTO TUESDAY...KEEPING THE CWA DRY. THE AIR MASS WILL WARM
UP UNDER SUN ANGLE EQUIVALENT TO LATE AUGUST...WITH MAX TEMPS IN
THE LOWER TO MID 80S ON SUNDAY TO THE UPPER 80S TO NEAR 90 ON
TUESDAY. A COLD FRONT WILL APPROACH THE AREA FROM THE NORTH ON
WEDNESDAY...BUT IT IS TOO EARLY TO TELL IF IT WILL STALL JUST
NORTH OF THE CWA OR MAKE IT INTO THE CWA. MOST OF THE MID AND
UPPER LEVEL JET ENERGY WILL STAY TO THE NORTH IN EITHER CASE...BUT
A CLOSER FRONT COULD MEAN A BETTER CHANCE OF DIURNAL CONVECTION
WITH MAX TEMPS WELL UP INTO THE 80S.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS CURRENTLY. SURFACE HIGH CENTER TO OUR EAST
OFFSHORE. UPPER TROUGH AND ASSOCIATED COLD FRONT TO OUR WEST.
SOUTHERLY LOW LEVEL FLOW IN PROGRESS OVER OUR REGION. LATEST ACARS
SOUNDINGS AT CAE CONFIRM SOUTHERLY LOW LEVEL AROUND 30 KT AT 1KFT.
BETTER MOISTURE AND LOW LEVEL MOISTURE CONVERGENCE JUST TO OUR
WEST WHERE A BAND OF SHOWERS CURRENTLY STRETCHES FROM NE GA SW TO
W CENT GA...MOVING NE. LATEST HIGH RESOLUTION MODELS AND RADAR
TRENDS SUGGEST SCATTERED SHOWERS COULD AFFECT OUR TERMINALS LATE
TONIGHT INTO FRIDAY MORNING. IN ADDITION...A MOIST S TO SSW LOW
LEVEL FLOW COULD PROMOTE SOME STRATUS. MODEL CONSENSUS SUGGESTS
MVFR CIGS POSSIBLE. MODELS GENERALLY SUGGEST BANDS OF SHOWERS AND
POSSIBLE THUNDERSTORMS TO AFFECT OUR TERMINALS FRIDAY AFTERNOON
AND EVENING. FOR NOW...WILL HANDLE WITH PREDOMINATE VCSH...WITH
TEMPO SHRA DURING TIME PERIODS WHERE PRECIP APPEARS MORE LIKELY.
MAIN COLD FRONT DOES NOT APPEAR WILL COME THROUGH UNTIL EARLY
SATURDAY MORNING.
EXTENDED AVIATION OUTLOOK...CHANCE OF SHOWERS AND RESTRICTIONS
POSSIBLE THROUGH SATURDAY MORNING. NO SIGNIFICANT IMPACTS TO
AVIATION SATURDAY AFTERNOON THROUGH TUESDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS POCATELLO ID
742 PM MDT SAT APR 23 2016
.UPDATE...UPPER LOW CONTINUING TO SLIDE EAST INTO SW WYOMING THIS
EVENING PER SATELLITE IMAGERY. SFC LOW REMAINS OVER IDAHO/MONTANA
BORDER WITH SHOWERS SLIDING SOUTHEAST ACROSS THE FORECAST AREA.
SFC GRADIENT WEAKER THAN ANTICIPATED AND SHOWER ACTIVITY HELPING
TO PRECLUDE DEVELOPMENT OF THE STRONG WINDS. WIND TREND FROM RAP
AND HRRR INDICATING SLOW DECREASE OF WINDS REMAINDER OF THIS
EVENING...SUPPORTED BY EARLIER GUIDANCE. THUS HAVE LET ADVISORY GO
EARLY. HAVE ADJUSTED WIND FORECAST DOWN SLIGHTLY REMAINDER OF
TONIGHT PERIOD OTHERWISE REMAINDER OF FORECAST IN GOOD SHAPE AND
NO OTHER CHANGES ANTICIPATED. DMH
&&
.PREV DISCUSSION... /ISSUED 221 PM MDT SAT APR 23 2016/
SHORT TERM...CURRENT RADAR IMAGERY HAS THE CENTER OF CIRCULATION
OF THESE SHOWERS ROUGHLY WHERE INTERSTATE 84 CROSSES THE IDAHO
AND UTAH STATE LINE. THIS DISTURBANCE TRACKS INTO SOUTHERN WYOMING
TONIGHT WITH WRAP AROUND EXPECTED OVER THE EASTERN HIGHLANDS.
SURFACE WINDS ARE GUSTING TO AROUND 45 MPH JUST WEST OF BURLEY AND
WILL LIKELY PICK UP ALONG I84/I86 AS SOME OF THE SHOWERS BREAK OFF
THE NEXT COUPLE OF HOURS. WILL KEEP THE CURRENT WIND ADVISORY IN
EFFECT FOR THIS EVENING. THINK THE SHOWERS ARE DELAYING THE ONSET
OF THE WINDS. SNOW LEVELS DROP TO ABOUT 7000 FEET ELEVATION OVER
THE EASTERN HIGHLANDS TONIGHT...THEN REBOUND UP TWO TO THREE
HUNDRED FEET DURING THE DAY. SNOW SHOULD ACCUMULATE UP TO 5 INCHES
OVER THE MOUNTAINS AROUND DRIGGS THROUGH MONDAY AFTERNOON. TETON
PASS MOST AT RISK FOR ACCUMULATION. TRANSITORY RIDGE BUILDS IN
SATURDAY NIGHT AND EARLY SUNDAY PROVIDING A BREAK FROM SHOWERS FOR
MOST OF THE VALLEY AREAS. OROGRAPHICS FAVOR SOME SHOWERS BETWEEN
DRIGGS AND ISLAND PARK. MODELS FAVOR THE NEXT DISTURBANCE TRACKING
ACROSS NORTHERN NEVADA AND UTAH MONDAY AND TUESDAY. 700 MB WINDS
SHOW SOME POTENTIAL FOR BANDING OF PRECIPITATION OVER THE
INTERSTATE 86 STRETCH FROM POCATELLO TO BURELY...BUT SNOW LEVELS
SHOULD BE AT OR ABOVE ABOUT 6200 FEET ELEVATION. ALSO HAVE
PROBLEMS WITH LIQUID WATER CONTENT...GFS APPEARS TO HAVE SOME
CONVECTIVE FEED BACK PRESENT IN THE MODEL AT TIMES. WILL PROBABLY
TAKE A COUPLE OF MODEL RUNS TO PLACE PRECIPATION AMOUNTS. RS
LONG TERM...TUESDAY THROUGH SATURDAY NIGHT. LOOK FOR A LINGERING
SYSTEM EARLY TUESDAY BRINGING GOOD PRECIPITATION CHANCES
PARTICULARLY FOR OUR EASTERN AREAS. MOUNTAINS IN THE SOUTHEAST
HIGHLANDS WILL LIKELY SEE 1 TO 2 INCHES OF SNOW. THE GFS MODEL
CONTINUES TO SHOW MORE PRECIPITATION THAN THE ECMWF MODEL. THE ECMWF
MODEL SHOWS STRONGER RIDGING THAN THE GFS ON WEDNESDAY. THUS..THE
ECMWF MODEL IS DRIER. THE GFS MODEL SHOWS AFTERNOON MOUNTAIN SHOWERS
DEVELOPING ON WEDNESDAY. THURSDAY INTO FRIDAY BOTH MODELS BRING AN
UPPER LEVEL LOW OVER UTAH BRINGING SHOWERS ACROSS THE AREA...
PARTICULARLY OUR SOUTHERN AREAS. THE ECMWF MODEL THEN BRINGS IN HIGH
PRESSURE RIDGING QUICKER THAN THE GFS MODEL BRINGING DRY CONDITIONS
BY SATURDAY AFTERNOON. THE GFS KEEPS LINGERING PRECIPITATION ACROSS
THE AREA INTO SATURDAY EVENING PARTICULARLY FOR OUR EASTERN AREAS.
EXPECT BELOW NORMAL TEMPERATURES EARLY IN THE PERIOD SLOWLY RISING
TO NEAR NORMAL BY THE END OF THE PERIOD. WYATT
AVIATION...AN UPPER LEVEL LOW IS MOVING OVER THE AREA TODAY. EXPECT
VICINITY THUNDERSTORMS FOR THE TAF SITES THIS AFTERNOON PARTICULARLY
FOR KPIH AND KIDA. LOOK FOR SHOWERS FOR THE SNAKE RIVER PLAIN TAF
SITES BRINGING MVFR CONDITIONS THIS AFTERNOON INTO THE EVENING. CIGS
WILL GO DOWN TO IFR DURING PERIOD OF RAIN SHOWERS ON STATION. KSUN
SHOULD REMAIN VFR WITH VICINITY SHOWERS THIS AFTERNOON AND EVENING.
HOWEVER...MVFR CIGS ARE POSSIBLE FOR KSUN WITH HEAVIER SHOWERS ON
STATION. EXPECT BREEZY TO MODERATE WINDS BY MID TO LATE AFTERNOON.
WINDS SHOULD CONTINUE THROUGH MOST OF THE NIGHT AND START TAPERING
OFF BY EARLY TO MID TOMORROW MORNING. WYATT
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
222 AM EDT FRI APR 22 2016
.SYNOPSIS...
ISSUED AT 135 AM EDT FRI APR 22 2016
A FEW LINGERING SHOWERS CAN BE EXPECTED TODAY...MAINLY ALONG AND
EAST OF STATE HIGHWAY 31. A RUMBLE OF THUNDER IS POSSIBLE. HIGHS
TODAY WILL BE IN THE LOW TO MID 60S...EXCEPT COOLER NEAR LAKE
MICHIGAN. SKIES SHOULD CLEAR TONIGHT WITH LOWS DIPPING TO AROUND
40 DEGREES. SOME OF THE LOCALLY COLDER SPOTS MAY FALL INTO THE
UPPER 30S. PLEASANT WEATHER CAN BE EXPECTED SATURDAY WITH MOSTLY
SUNNY SKIES AND HIGHS IN THE MID TO UPPER 60S.
&&
.UPDATE...
ISSUED AT 804 PM EDT THU APR 21 2016
LEAD VORT MAX WILL CONTINUE TO SHIFT ACROSS NORTHWEST OHIO OVER
THE NEXT HOUR OR TWO. EXTENT/INTENSITY OF THUNDER HAS DIMINISHED
WITH THIS AREA OF RAIN OVER THE PAST FEW HOURS AS FORCING WITH
THIS VORT MAX HAS OUTRUN BETTER INSTABILITY. ADDITIONAL SCATTERED
STORMS HAVE DEVELOPED ACROSS WESTERN PORTIONS OF THE FORECAST AREA
EARLY THIS EVENING COINCIDENT WITH PRIMARY 500-1000 J/KG
INSTABILITY AXIS. INSTABILITY SHOULD BECOME PROGRESSIVELY MORE
ELEVATED OVER NEXT SEVERAL HOURS WHICH SHOULD RESULT IN DOWNWARD
TREND OF CONVECTIVE INTENSITY. STILL SOME LOW END POTENTIAL OF
SOME SMALL HAIL/LOCALIZED WIND GUSTS IN EXCESS OF 40 MPH WITH
STRONGER CORES ACROSS MAINLY WESTERN HALF OF THE FORECAST AREA
THROUGH 03Z HOWEVER. WILL KEEP LIKELY RAIN/CHANCE THUNDER MENTION
GOING THROUGH THE EVENING WITH HIGHEST POPS IN THE SOUTH DUE TO
DIGGING NATURE OF APPROACHING UPPER TROUGH. POCKET OF STEEPER MID
LEVEL LAPSE RATES ADVECTING INTO THE AREA ACCOMPANYING THIS
FEATURE SHOULD PROLONG ISOLD THUNDER POTENTIAL INTO THE OVERNIGHT
HOURS...AND MAINLY ACROSS THE SOUTH/SOUTHEAST. ONLY TWEAK FOR THE
EVENING UPDATE WAS TO REFINE POPS FOR CURRENT TRENDS BUT OTHER
FORECAST ELEMENTS APPEAR TO BE ON TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 334 PM EDT THU APR 21 2016
MAIN FOCUS ON CONVECTIVE DEVELOPMENT IN FAR WESTERN PARTS OF
FORECAST AREA AS WELL AS UPSTREAM NEAR THE UPPER LOW.
SOME POCKETS OF CLEARING/BREAKS HAVE OCCURRED ALLOWING TEMPERATURES
TO CLIMB INTO THE 60S ACROSS THE AREA AND MAKING A RUN AT 70 IN
WEST/SW LOCATIONS. NARROW PLUME OF HIGHER DEWPOINTS WAS NOW SHIFTING
ACROSS THE FORECAST AREA WITH SLIGHTLY LOWER READINGS UNDER THE
CLEARING AND WHERE CONVECTION WAS ATTEMPTING TO POP. ISOLATED
SHOWERS/STORMS HAVE BEEN DEVELOPING OVER THE LAST 30 TO 60
MINUTES...LIKELY CONTAINING AT LEAST SOME SMALL HAIL. ARC OF STORMS
ONGOING CLOSER TO THE UPPER LOW FROM WATERLOO IOWA TO MOLINE TO WEST
OF SPRINGFIELD IL. HRRR SUGGESTS THIS ACTIVITY WILL MOVE SLOWLY
NORTHEAST AND EXPAND MORE IN THE 22 TO 02Z WINDOW. HAVE KEPT HIGH
SCT TO NUMEROUS SHOWERS WITH MENTION OF THUNDER THROUGH THE EVENING.
EVE SHIFT MAY NEED TO ADJUST FOR TRENDS. TEMPERATURES WILL SLOWLY
FALL THIS EVENING AS AREA REMAINS IN THE WARM SECTOR...WITH SLOW
FALL OVERNIGHT AS THE COLD FRONT APPROACHES.
UPPER LOW WILL CONTINUE TO OPEN AND LINGER FRIDAY...ONLY DRIFTING
SLOWLY EAST INTO SOUTHERN OHIO BY 00Z SAT. GIVEN UPSTREAM TRENDS
UNDER THE UPPER LOW WITH SCATTERED SHOWERS AROUND...SEE NO REASON TO
MAKE ANY MAJOR CHANGES TO SE HALF OF THE AREA INTO MID AFTERNOON
WITH SCATTERED SHOWERS. WHILE NOT INTRODUCED...MAY NEED TO ADD
PASSING MENTION OF THUNDER AS SFC CAPE INCREASES TO AROUND 500 J/KG
AND MARGINAL LAPSE RATES.
&&
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 334 PM EDT THU APR 21 2016
A MORE PROGRESSIVE FLOW PATTERN WILL TAKE HOLD ON THE LOWER 48 THIS
WEEKEND INTO NEXT WEEK AS A SERIES OF WESTERN CONUS SHORTWAVES
EJECT/SHEAR EAST INTO MORE CONFLUENT/WNW FLOW OVER THE GREAT LAKES
REGION. LUCKILY THE WEEKEND WILL FEATURE DRY CONDITIONS WITH HIGH
PRESSURE IN CONTROL IN BETWEEN WAVES. SATURDAY THE COOLER/SUNNIER
DAY UNDER HIGH PRESSURE WITH WARM ADVECTION BEHIND SFC HIGH ALLOWING
HIGHS TO RETURN INTO THE 70S BY SUNDAY. FRONTAL SYSTEMS WITH THE
AFOREMENTIONED SHORTWAVES THEN BRING MORE UNSETTLED WX NEXT
WEEK...WITH LATEST GUIDANCE FAVORING MONDAY/MONDAY NIGHT AND
WEDNESDAY/WEDNESDAY NIGHT FOR HIGHER POPS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 123 AM EDT FRI APR 22 2016
A WEAK UPPER LOW WILL DRIFT EAST OVER THE AREA TODAY. A COLD FRONT
WILL MOVE ACROSS THE AREA BEHIND THIS SYSTEM. SOME FOG IS
POSSIBLE...EARLY THIS MORNING ESPECIALLY AT SBN IN CONJUNCTION
WITH THE FRONT PASSAGE. SOME SHOWERS ARE POSSIBLE LATER
TODAY...ESPECIALLY AT FT WAYNE AS THE LOW MOVES EAST AND THE FRONT
MOVES ACROSS THE AREA. FOR NOW...HAVE KEPT AFTERNOON SHOWERS OUT
OF FT WAYNE GIVEN UNCERTAINTY...ALTHOUGH THESE SHOWERS MAY NEED TO
BE ADDED LATER.
&&
.MARINE...
WEBCAMS SHOWING A GOOD DEAL OF DENSE FOG IN THE NEARSHORE WATERS
WARRANTING ISSUANCE OF A MARINE DENSE FOG ADVISORY INTO THIS
EVENING UNTIL COLDER AIR STARTS TO MOVE IN. WILL ALSO HOIST SMALL
CRAFT ADVISORY FOR FRIDAY INTO FRIDAY EVENING FOR INCREASING NW
FLOW AND HIGHER WAVES.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...DENSE FOG ADVISORY UNTIL 2 AM EDT EARLY THIS MORNING FOR LMZ043-
046.
SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 2 AM EDT SATURDAY
FOR LMZ043-046.
&&
$$
UPDATE...MARSILI
SYNOPSIS...SKIPPER
SHORT TERM...FISHER
LONG TERM...STEINWEDEL
AVIATION...SKIPPER
MARINE...FISHER
VISIT US AT WWW.WEATHER.GOV/IWX
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
1207 PM CDT FRI APR 22 2016
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 300 AM CDT FRI APR 22 2016
07Z water vapor imagery showed an upper trough over IL moving to the
east and an upper low off the OR coast. In between these two lows
was an upper ridge along the Rockies. Surface obs showed a weak
ridge of high pressure gradually building south through the central
plains.
The forecast continues to call for dry weather today and tonight due
to no real forcing for precip within the upper ridge. Additionally
there should be some modest dry air advection with the surface ridge
through the day preventing any real chance for precip. There is an
area of low clouds moving south through the MO river valley. RAP and
NAM progs show these clouds should hold together long enough to move
into northeast KS this morning. Otherwise there should be good
insolation by the afternoon. Because of this and with forecast
soundings mixing the boundary layer to near 800 MB, have adjusted
highs for today up a little from the prev forecast expecting
readings between 70 and 75. The surface ridge is progged to move off
to the east tonight with winds freshening from the southeast.
Although the gradient does not appear to be all that strong.
Therefore think low lying areas may decouple with winds remaining
fairly light through the night allowing lows to fall into the mid
40s. Elevated locations may see enough wind through the night for
lows to be around 50.
.LONG TERM...(Saturday through Thursday)
Issued at 300 AM CDT FRI APR 22 2016
Only minor edits to the extended forecast with model guidance
remaining fairly similar to the previous forecast package. Upper
ridging in control with a developing sfc trough to the west Saturday
afternoon will bring gusty south winds to the CWA. Speeds between 15
and 25 mph are likely with gusts peaking at 30 to 35 mph. Gulf
moisture increases dewpoints to the 50s while highs warm back into
the upper 70s and lower 80s. Chances for thunderstorms commence
Saturday evening as a lee trough lifts eastward over the western
plains. GFS and NAM runs at 00Z continue to advertise a slightly
faster progression of the sfc low and weak upper impulse, developing
scattered showers and thunderstorms over north central Kansas
overnight. The ECMWF is slightly slower with these features with the
optimal chances arriving Mon at 12Z. Have adjusted pops accordingly,
increasing the probabilities Sunday afternoon and evening as the
upper trough axis crosses southern NE, while the sfc low and dryline
are depicted similarly over central Kansas 00Z Monday. Steepening
lapse rates and warm moist conditions ahead of the system translate
up to 2000 J/KG of sfc based CAPE with little CIN to prevent
thunderstorm development. Main uncertainty will be mesoscale in
nature such as cloud cover and morning precip which could hinder
severity of convection overnight. However, with this setup any
updraft that does form in the late afternoon will likely be severe
with speed shear up to 6 km near 40 kts. 0-1 km shear enhances with
the LLJ by 00Z as well increasing the threat for tornadoes with any
isolated convection. Otherwise large hail and damaging winds are the
most likely hazards as convection is likely to congeal into a line
as tracks over the CWA Sunday evening.
The passing frontal boundary is still hanging up over southeast
Kansas on Monday with the GFS and ECMWF generating additional
convection Monday evening near the boundary over far east central
and southeast Kansas. Enough MUCAPE and effective shear in this area
will support a few strong to severe storms.
Long term models are still advertising a possible severe weather
event for a portion of the central plains region Tuesday afternoon
and evening as a strong negatively tilted trough lifts out of the
Inter-mountain West. Main discrepancies lie with the exact position
of the frontal boundary and timing of the approaching system as the
boundary lifts northward as a warm front through the day. ECMWF is
faster with the sfc low, lifting the warm front further north
with convection, placing the boundary over northern KS and most of
the CWA within the warm sector. The GFS however is still showing the
warm front bisecting the CWA west to east by 00Z with severe
convection focusing along and north of the boundary. er north with
the dryline centered over central KS. Meanwhile the slower GFS has
been persistent with the warm front bisecting the CWA from west to
east by 00Z Monday. GFS has also been the stronger solution with
over 2000 J/KG of sfc CAPE, minimal CIN and 0-6 KM bulk shear up to
50 kts. Lower lvl shear is stronger as well, enhancing the tornado
threat. Will need to keep monitoring changes, but it does appear
likely for a few severe storms in the area and have increased precip
chances during this period.
The remainder of the extended is more uncertain as the upper low
slowly exits eastward and dry conditions return on Thursday. Next
upper trough appears slower with this package so have backed off on
pops for Thursday at this time.
&&
.AVIATION...(For the 18Z TAFS through 18Z Saturday Afternoon)
Issued at 1156 AM CDT FRI APR 22 2016
For the 18z TAFs, VFR conditions should hold for the afternoon
into the evening as current stratus deck continues to erode with
the heating of the day. Not confident enough at this point to add
fog for the 11-13Z time frame in the morning. However, there is a
possibility for some reduced VIS and patchy FG around 12Z mainly
at KTOP/KFOE. Have left mention out of the TAFs for now, but this
will be something to monitor TAFs for if decoupling allows for the
set up to occur. Winds will increase by late morning from the
SSE.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Drake
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
615 AM CDT FRI APR 22 2016
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 300 AM CDT FRI APR 22 2016
07Z water vapor imagery showed an upper trough over IL moving to the
east and an upper low off the OR coast. In between these two lows
was an upper ridge along the Rockies. Surface obs showed a weak
ridge of high pressure gradually building south through the central
plains.
The forecast continues to call for dry weather today and tonight due
to no real forcing for precip within the upper ridge. Additionally
there should be some modest dry air advection with the surface ridge
through the day preventing any real chance for precip. There is an
area of low clouds moving south through the MO river valley. RAP and
NAM progs show these clouds should hold together long enough to move
into northeast KS this morning. Otherwise there should be good
insolation by the afternoon. Because of this and with forecast
soundings mixing the boundary layer to near 800 MB, have adjusted
highs for today up a little from the prev forecast expecting
readings between 70 and 75. The surface ridge is progged to move off
to the east tonight with winds freshening from the southeast.
Although the gradient does not appear to be all that strong.
Therefore think low lying areas may decouple with winds remaining
fairly light through the night allowing lows to fall into the mid
40s. Elevated locations may see enough wind through the night for
lows to be around 50.
.LONG TERM...(Saturday through Thursday)
Issued at 300 AM CDT FRI APR 22 2016
Only minor edits to the extended forecast with model guidance
remaining fairly similar to the previous forecast package. Upper
ridging in control with a developing sfc trough to the west Saturday
afternoon will bring gusty south winds to the CWA. Speeds between 15
and 25 mph are likely with gusts peaking at 30 to 35 mph. Gulf
moisture increases dewpoints to the 50s while highs warm back into
the upper 70s and lower 80s. Chances for thunderstorms commence
Saturday evening as a lee trough lifts eastward over the western
plains. GFS and NAM runs at 00Z continue to advertise a slightly
faster progression of the sfc low and weak upper impulse, developing
scattered showers and thunderstorms over north central Kansas
overnight. The ECMWF is slightly slower with these features with the
optimal chances arriving Mon at 12Z. Have adjusted pops accordingly,
increasing the probabilities Sunday afternoon and evening as the
upper trough axis crosses southern NE, while the sfc low and dryline
are depicted similarly over central Kansas 00Z Monday. Steepening
lapse rates and warm moist conditions ahead of the system translate
up to 2000 J/KG of sfc based CAPE with little CIN to prevent
thunderstorm development. Main uncertainty will be mesoscale in
nature such as cloud cover and morning precip which could hinder
severity of convection overnight. However, with this setup any
updraft that does form in the late afternoon will likely be severe
with speed shear up to 6 km near 40 kts. 0-1 km shear enhances with
the LLJ by 00Z as well increasing the threat for tornadoes with any
isolated convection. Otherwise large hail and damaging winds are the
most likely hazards as convection is likely to congeal into a line
as tracks over the CWA Sunday evening.
The passing frontal boundary is still hanging up over southeast
Kansas on Monday with the GFS and ECMWF generating additional
convection Monday evening near the boundary over far east central
and southeast Kansas. Enough MUCAPE and effective shear in this area
will support a few strong to severe storms.
Long term models are still advertising a possible severe weather
event for a portion of the central plains region Tuesday afternoon
and evening as a strong negatively tilted trough lifts out of the
Inter-mountain West. Main discrepancies lie with the exact position
of the frontal boundary and timing of the approaching system as the
boundary lifts northward as a warm front through the day. ECMWF is
faster with the sfc low, lifting the warm front further north
with convection, placing the boundary over northern KS and most of
the CWA within the warm sector. The GFS however is still showing the
warm front bisecting the CWA west to east by 00Z with severe
convection focusing along and north of the boundary. er north with
the dryline centered over central KS. Meanwhile the slower GFS has
been persistent with the warm front bisecting the CWA from west to
east by 00Z Monday. GFS has also been the stronger solution with
over 2000 J/KG of sfc CAPE, minimal CIN and 0-6 KM bulk shear up to
50 kts. Lower lvl shear is stronger as well, enhancing the tornado
threat. Will need to keep monitoring changes, but it does appear
likely for a few severe storms in the area and have increased precip
chances during this period.
The remainder of the extended is more uncertain as the upper low
slowly exits eastward and dry conditions return on Thursday. Next
upper trough appears slower with this package so have backed off on
pops for Thursday at this time.
&&
.AVIATION...(For the 12Z TAFS through 12Z Saturday Morning)
Issued at 615 AM CDT FRI APR 22 2016
The RAP and NAM eventually caught onto the MVFR stratus moving
south from the mid MO river valley, and they hang onto the low
clouds through much of the morning. Biggest uncertainty is whether
CIGS remain at or above 1 KFT or dip below 1 KFT. Looking at OBS
upstream, there is a chance for IFR CIGS for several hours this
morning. Have the CIGS scattering out around noon based on the
RAP. Once the clouds scatter out, VFR conditions should prevail
for the rest of the period.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Wolters
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
302 AM CDT FRI APR 22 2016
.SHORT TERM...(Today and Tonight)
Issued at 300 AM CDT FRI APR 22 2016
07Z water vapor imagery showed an upper trough over IL moving to the
east and an upper low off the OR coast. In between these two lows
was an upper ridge along the Rockies. Surface obs showed a weak
ridge of high pressure gradually building south through the central
plains.
The forecast continues to call for dry weather today and tonight due
to no real forcing for precip within the upper ridge. Additionally
there should be some modest dry air advection with the surface ridge
through the day preventing any real chance for precip. There is an
area of low clouds moving south through the MO river valley. RAP and
NAM progs show these clouds should hold together long enough to move
into northeast KS this morning. Otherwise there should be good
insolation by the afternoon. Because of this and with forecast
soundings mixing the boundary layer to near 800 MB, have adjusted
highs for today up a little from the prev forecast expecting
readings between 70 and 75. The surface ridge is progged to move off
to the east tonight with winds freshening from the southeast.
Although the gradient does not appear to be all that strong.
Therefore think low lying areas may decouple with winds remaining
fairly light through the night allowing lows to fall into the mid
40s. Elevated locations may see enough wind through the night for
lows to be around 50.
.LONG TERM...(Saturday through Thursday)
Issued at 300 AM CDT FRI APR 22 2016
Only minor edits to the extended forecast with model guidance
remaining fairly similar to the previous forecast package. Upper
ridging in control with a developing sfc trough to the west Saturday
afternoon will bring gusty south winds to the CWA. Speeds between 15
and 25 mph are likely with gusts peaking at 30 to 35 mph. Gulf
moisture increases dewpoints to the 50s while highs warm back into
the upper 70s and lower 80s. Chances for thunderstorms commence
Saturday evening as a lee trough lifts eastward over the western
plains. GFS and NAM runs at 00Z continue to advertise a slightly
faster progression of the sfc low and weak upper impulse, developing
scattered showers and thunderstorms over north central Kansas
overnight. The ECMWF is slightly slower with these features with the
optimal chances arriving Mon at 12Z. Have adjusted pops accordingly,
increasing the probabilities Sunday afternoon and evening as the
upper trough axis crosses southern NE, while the sfc low and dryline
are depicted similarly over central Kansas 00Z Monday. Steepening
lapse rates and warm moist conditions ahead of the system translate
up to 2000 J/KG of sfc based CAPE with little CIN to prevent
thunderstorm development. Main uncertainty will be mesoscale in
nature such as cloud cover and morning precip which could hinder
severity of convection overnight. However, with this setup any
updraft that does form in the late afternoon will likely be severe
with speed shear up to 6 km near 40 kts. 0-1 km shear enhances with
the LLJ by 00Z as well increasing the threat for tornadoes with any
isolated convection. Otherwise large hail and damaging winds are the
most likely hazards as convection is likely to congeal into a line
as tracks over the CWA Sunday evening.
The passing frontal boundary is still hanging up over southeast
Kansas on Monday with the GFS and ECMWF generating additional
convection Monday evening near the boundary over far east central
and southeast Kansas. Enough MUCAPE and effective shear in this area
will support a few strong to severe storms.
Long term models are still advertising a possible severe weather
event for a portion of the central plains region Tuesday afternoon
and evening as a strong negatively tilted trough lifts out of the
Inter-mountain West. Main discrepancies lie with the exact position
of the frontal boundary and timing of the approaching system as the
boundary lifts northward as a warm front through the day. ECMWF is
faster with the sfc low, lifting the warm front further north
with convection, placing the boundary over northern KS and most of
the CWA within the warm sector. The GFS however is still showing the
warm front bisecting the CWA west to east by 00Z with severe
convection focusing along and north of the boundary. er north with
the dryline centered over central KS. Meanwhile the slower GFS has
been persistent with the warm front bisecting the CWA from west to
east by 00Z Monday. GFS has also been the stronger solution with
over 2000 J/KG of sfc CAPE, minimal CIN and 0-6 KM bulk shear up to
50 kts. Lower lvl shear is stronger as well, enhancing the tornado
threat. Will need to keep monitoring changes, but it does appear
likely for a few severe storms in the area and have increased precip
chances during this period.
The remainder of the extended is more uncertain as the upper low
slowly exits eastward and dry conditions return on Thursday. Next
upper trough appears slower with this package so have backed off on
pops for Thursday at this time.
&&
.AVIATION...(For the 06Z TAFS through 06Z Friday Night)
Issued at 1201 AM CDT FRI APR 22 2016
Only issue at TOP/MHK will be potential for BR development,
although soundings indicate saturated layer is rather shallow and
wind speeds as high comes in still around 10kts near the NE
border. Will carry MVFR tempo visby at this time and monitor for
updates.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...67
AREA FORECAST DISCUSSION
NWS JACKSON KY
200 AM EDT FRI APR 22 2016
.UPDATE...
ISSUED AT 200 AM EDT FRI APR 22 2016
FIRST ROUND OF SHOWER ACTIVITY PUSHING ACROSS THE HIGHER TERRAIN
WILL EXIT THE COMMONWEALTH WITHIN THE NEXT HOUR OR TWO. A
SECOND...AND WHAT HAS BEEN A MORE PRONOUNCED ONE...CONTINUES TO
PUSH EAST ACROSS WESTERN KENTUCKY. WILL CONTINUE TO WATCH THIS
CONVECTIVE LINE...BUT GUST FRONT DEVELOPMENT AND WEAKENING OF
UPPER LOW DO NOT BODE TERRIBLY WELL FOR BONAFIDE RAIN CHANCES
SOUTH OF HAL ROGERS PARKWAY FROM THIS ROUND. THESE AREAS WILL HAVE
TO WAIT UNTIL REDEVELOPMENT OCCURS THIS AFTERNOON.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 345 PM EDT THU APR 21 2016
LATEST GOES WV IMAGERY SHOWS MAIN UPPER LEVEL LOW SHIFTING INTO
WESTERN INDIANA THIS AFTERNOON. AS THIS LOW SHIFTS EAST OVERNIGHT
TONIGHT...IT IS EXPECTED TO BECOME AN OPEN WAVE AND WEAKEN. THE
OPEN WAVE WILL THEN DROP SOUTHEASTWARD THROUGH EASTERN KENTUCKY
FRIDAY AFTERNOON/EVENING BEFORE SHIFTING OUT OF OUR AREA BY THE
END OF THE SHORT TERM.
AT THE SURFACE...THE STACKED SFC LOW IS CURRENTLY SWINGING INTO
WESTERN INDIANA WITH A COLD FRONT EXTENDING SOUTH THROUGH WESTERN
KENTUCKY. THIS FRONT IS PROGGED TO MOVE THROUGH OUR AREA LATE THIS
EVENING INTO THE OVERNIGHT HOURS BRINGING WITH IT CHANCES FOR RAIN
AND PERHAPS SOME ISOLATED THUNDER. FOR NOW...SOUTHEASTERLY FLOW
AND DOWNSLOPING EFFECTS HAVE KEPT THE MAJORITY OF EASTERN
KENTUCKY VERY DRY. IN FACT...DEW POINTS ONCE AGAIN DROPPED DOWN
INTO 30S LEADING TO RH VALUES IN 20 AND LOW 30 PERCENT RANGE
/MAINLY IN THE EASTERN HALF OF THE AREA/. THIS WILL ONLY ACT
FURTHER TO SLOW DOWN THE MOISTENING OF THE COLUMN ONCE RAINFALL
MOVES INTO THE REGION...CUTTING DOWN ON ACCUMULATION AMOUNTS.
THE MOST RECENT HIGH RES MODELS SHOW THE MAIN AREA OF RAINFALL
ENTERING WESTERN KENTUCKY AROUND 00Z AND THEN PROGRESSING
EASTWARD DURING THE OVERNIGHT HOURS. ONCE THE FRONT EXITS THE
REGION BY DAWN...SHOWERS WILL LIKELY CONTINUE ON AND OFF
THROUGHOUT THE REMAINDER OF THE DAY INTO EARLY SATURDAY MORNING AS
THE UPPER LEVEL FEATURE PASSES THROUGH. THERE APPEARS TO BE
BETTER INSTABILITY ASSOCIATED WITH THE UPPER LEVEL FEATURE SO
INCLUDED CHANCES FOR THUNDER FOR MOST OF THE DAY TOMORROW. ANY
REMAINING SHOWER ACTIVITY SHOULD EXIT EASTERN KENTUCKY BY DAWN ON
SATURDAY ALLOWING FOR ANOTHER DRY AND SUNNY WEEKEND.
TEMPERATURES WILL REMAIN MILD THROUGH THE SHORT TERM AS RAIN AND
CLOUD COVER INHIBIT RADIATIONAL COOLING/HEATING...WITH LOWS
GENERALLY IN 50S AND AFTERNOON HIGHS IN THE UPPER 60S AND LOW 70S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 400 PM EDT THU APR 21 2016
HIGH PRESSURE AND DRY NORTHERLY AIR WILL BE IN PLACE STARTING THE
DAY SATURDAY...CONTINUING INTO THE DAY SUNDAY AS WINDS BECOME MORE
SRLY ON THE WESTERLY SIDE OF THE HIGH PRESSURE SYSTEM. ABUNDANT SUN
BUT NORTHERLY WINDS ON SATURDAY WILL KEEP AFTERNOON TEMPS IN THE
UPPER 60S AND LOW 70S...BUT THE INTRODUCTION OF SOUTHERLY WINDS WILL
BOOST TEMPS TO AROUND 80 DEGREES BY SUNDAY. WINDS WILL ALSO BE ON
THE INCREASE SUNDAY AS AN UPPER LEVEL SHORTWAVE AND SURFACE LOW
PRESSURE SYSTEM NEAR THE REGION FROM THE CENTRAL PLAINS DURING THE
DAY. MODELS ARE CONTINUING TO TREND BACK ON BOTH THE TIMING OF THE
ASSOCIATED COLD FRONT AS WELL AS THE ASSOCIATED PRECIP AS IT SLOWLY
MOVES EASTWARD THROUGHOUT THE DAY SUNDAY. AT THIS TIME...MODELS ARE
CONTINUING TO KEEP KY DRY THROUGH THE DAY MONDAY...SO AFTER
COLLABORATING WITH OTHER OFFICES AND LOOKING AT LATEST MODEL
DATA...DECIDED TO LEAVE OUT MENTION OF SLIGHT CHANCE OR ABOVE POPS.
THE COLD FRONT WILL ELONGATE ITSELF FROM WEST TO EAST NORTH OF THE
OHIO RIVER BY MONDAY AFTERNOON...BEFORE FINALLY DROPPING SOUTHWARD
INTO THE STATE MONDAY NIGHT. BY THIS POINT THE UPPER LEVEL WAVE AS
WELL AS THE SURFACE LOW WILL QUICKLY FADE OUT...WHILE ANOTHER
SHORTWAVE AND CLOSED UPPER LEVEL LOW BEGINS DEVELOPING JUST WEST OF
THE ORIGINAL. AT THE SURFACE THE NEW STRENGTHENING LOW PRESSURE
CENTER WILL ABSORB THE FRONTAL BOUNDARY...KEEPING IT STRUNG ACROSS
OR NEAR THE OHIO RIVER VALLEY IN SOME FORM. EXPECT THE BOUNDARY TO
OSCILLATE NORTH AND SOUTHWARD ACROSS THE STATE TUESDAY THROUGH
THURSDAY TRANSITIONING FROM A WARM TO A COLD FRONT AS IT MOVES NORTH
VS. SOUTH. REGARDLESS...IT WILL BE QUITE WEAK AS FAR AS OVERALL
MOISTURE ACROSS THE AREA...BUT CONTINUED WARM TEMPS ACROSS THE AREA
AND THE EXISTENCE OF THE LIFTING MECHANISM WILL KEEP THE POTENTIAL
FOR THUNDER IN THE FORECAST EACH DAY. TEMPS WILL GENERALLY REMAIN
AROUND 80 DEGREES IN THE AFTERNOON THROUGH THIS TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 200 AM EDT FRI APR 22 2016
MULTIPLE ROUNDS OF SHOWERS AND EMBEDDED THUNDERSTORMS WILL MOVE
THROUGH EASTERN KENTUCKY TODAY AHEAD OF AN UPPER LEVEL DISTURBANCE
AND COOL FRONT. MAINLY VFR CONDITIONS WILL YIELD TO MVFR CRITERIA
AT TIMES IN HEAVIER SHOWERS AND STORMS...BUT EXACT TIMING AND
SPATIAL EXTENT OF THIS REMAIN IN QUESTION. ROUND OF SHOWERS/STORMS
COMING OUT OF WESTERN KENTUCKY TONIGHT/FRIDAY MORNING SHOULD
PRIMARILY IMPACT KSYM...BEFORE ADDITIONAL ROUNDS DEVELOP LATER
THIS MORNING/AFTERNOON. WILL HAVE TO KEEP TABS ON TSRA DEVELOPMENT
FOR LATER TAF PACKAGES. PRECIPITATION WILL WIND DOWN LATE THIS
AFTERNOON AND THIS EVENING AS CEILINGS BEGIN TO LOWER TO LOW-
RANGE VFR CRITERIA TOWARD 06Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GUSEMAN
SHORT TERM...JVM
LONG TERM...JMW
AVIATION...GUSEMAN
Area Forecast Discussion
National Weather Service Louisville KY
105 AM EDT FRI APR 22 2016
...Updated Aviation Discussion...
...Forecast Update...
Issued at 949 PM EDT Thu Apr 21 2016
Watching line of storms crossing the Wabash River. The storms are
lined up along a corridor of relative instability. However, CIN is
starting to increase, and AMDAR soundings show a low level inversion
setting up, as well predicted by mesoscale models. The line went
right through the Evansville radar, which only showed velocities of
30-40 knots on the lowest scan as the line approached. ProbSvr has
dropped quite a bit over the last few volume scans, lightning has
decreased, and reflectivities have weakened slightly. These trends
all agree with the HRRR showing a weakening of the line as it moves
into southern Indiana. So, will go with the idea of the line
weakening, or at least not producing severe weather in the immediate
future. Will still keep an eye on it, of course.
.SHORT TERM (Now through Friday Night)...
Issued 303 PM EDT Thu Apr 21 2016
The Ohio Valley remains situated in the SW flow between upper ridge
axis to our east and vertically stacked low to our NW. A steady
plume of moisture will continue to ride SW to NE across our region
between these two features through the afternoon and evening. We`re
now beginning to see an eastward push to the activity as a wave
embedded in the southwest flow arrives. In addition to the eastward
push, seeing some convection fire. Expect that numerous showers and
scattered thunderstorms will be the rule for the remainder of the
afternoon, pushing east to a Lexington to Lake Cumberland line
through the evening. With freezing levels low, some small hail may
accompany brief heavy rainfall and a few cloud to ground ligthning
strikes.
Behind the main batch of precipitation, expect a brief lull in
activity as a dry slot works into the region. However as we approach
the evening into the overnight hours, another round of scattered to
numerous showers (and a few storms) will move into our west ahead of
the upper low. Given steeper lapse rates and low freezing levels,
some small hail will still be possible with these storms across our
west into the later evening hours. Expect that intensity and
coverage will diminish as we move through the overnight and lose
instability. Expect mainly scatteed showers exiting the east by dawn.
Lows tonight should be in the mid and upper 50s.
Upper low tracks across our northern CWA on Friday, which will yield
a cloudy and showery period driven by steep low and mid level lapse
rates. Enough instability should result for some thunder chances,
along with small hail/graupel given the low freezing levels. Will
carry scattered to numerous coverage mainly along and east of I-65
through the day. Highs will be noticeably cooler under
cloudy/showery upper low. Look for upper 60s to low 70s.
.LONG TERM (Saturday through Thursday)...
Issued at 303 PM EDT Wed Apr 20 2016
Saturday - Sunday Night...
Progressive upper ridging will build and transition through the
region over the weekend, bringing a return to dry and seasonably
warm temperatures. Saturday will be mostly sunny with a light NE
surface flow. With 850 temps expected to be around 7 to 8 C, expect
high temps in the low to mid 70s. Would be inclined to go a bit
higher, but will knock off a couple degrees given the surface wind
orientation and its generally cooler impact. Temperatures Saturday
evening, will be falling through the 60s.
A dry and cool Saturday night will see temps mostly in the upper 40s
and low 50s, although a few of our eastern spots may see mid 40s.
By Sunday, upper ridge axis will be directly overhead with high
temps recovering to up around 80. Will be inclined to go a degree or
two above MEX guidance for this day given the swing to southerly
flow and slightly deeper mixing. Sunday night will be continued
dry with slightly milder low temps in the upper 50s to around 60.
Monday - Monday Night...
Upper flow begins to flatten out to a more zonal look by the start
of the new work week in response to a passing northern stream wave.
This will allow a trailing cold front to sink southward toward the
Ohio River, becoming parallel to the upper flow as it does. At this
point, models suggest we could see some activity across our far
north by Monday afternoon/evening, however with dry air in place,
expect that things may be delayed a bit, much like we just saw with
today`s system. Models disagree on exact placement, but will tend to
lean toward the slower/drier outcome for now. Expect temps in the
low 80s on the south side of the frontal boundary. Monday night will
bring lows around 60 with a small chance of showers or t-storms
dependent on the setup mentioned above.
Tuesday - Thursday...
The mid week period looks to be more active as the frontal boundary
should be in the vicinity of the region. Do expect that areas along
the boundary would become unstable on the periphery of upper ridging
and with low level moisture pooling on the boundary. Meanwhile,
progressive upper flow would allow for some disturbances to pass
through and ultimately contribute to some convective organization.
For now, will continue with the fcst of temps in the mid and upper
70s and chances for scattered showers and t-storms during this time.
&&
.AVIATION (06Z TAF Update)...
Updated at 1256 AM EDT Fri Apr 22 2016
A line of showers/storms will reach SDF around 5-530z with brief
heavy downpours, lightning and possibily small hail. Upstream
observations have shown very little wind gusts as storms are mainly
elevated at this point.
Plan on this line to weaken some as it approaches LEX toward 7-8z,
and will hold off mentioning thunder as remaining instability should
diminish by then. At BWG, scattered showers may pass the terminal
early this morning, but the bulk of precipitaiton will stay north.
A lull in the activity is expected after sunrise this morning, until
the upper low over Illinois swings over the area. The combination of
the upper low, cold temps aloft and daytime heating will spark
another round of showers and scattered thunderstorms. This is most
likely to impact SDF/LEX during the afternoon. This weather system
should pass east of the area by 00z, giving way to improving
conditions for Friday evening into the weekend.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Update.........13
Short Term.....BJS
Long Term......BJS
Aviation.......ZT
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
353 PM EDT FRI APR 22 2016
.SYNOPSIS...
A COLD FRONT PUSHES ACROSS THE AREA AND OFF THE COAST TONIGHT
INTO EARLY SATURDAY MORNING. AN UPPER LEVEL DISTURBANCE WILL DROP
THROUGH THE REGION SATURDAY. HIGH PRESSURE RETURNS SATURDAY NIGHT
THROUGH MONDAY. THE NEXT COLD FRONT DROPS ACROSS THE REGION
TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
LATEST GOES WATER VAPOR IMAGERY DEPICTS THE UPPER CLOSED LOW OVER
THE OH VALLEY THIS AFTERNOON WITH A PLUME OF MOISTURE EXTENDING
ALONG THE SOUTHEAST COASTAL PLAIN INTO THE LOCAL AREA. THE COLD
FRONT STILL LAGS OVER CENTRAL OH/KY/TN. LATEST REGIONAL RADAR
DEPICTS BROAD AREA OF SHOWERS EAST OF INTERSTATE 95 WITH SCATTERED
SHOWERS WEST. ONLY LINGER THUNDER REMAINS OVER THE ERN SHORE NEAR
THE COAST. THE NEXT BATCH OF SHOWERS AND EMBEDDED THUNDER IS LOCATED
OVER CENTRAL AND EASTERN NC. HI-RES GUIDANCE LIFTS THE SHOWERS INTO
THE SE HALF OF THE LOCAL AREA THRU THE REST OF THE AFTERNOON.
ANOTHER AREA OF SHOWERS ASSOCIATED WITH THE NEXT PLUME OF MOISTURE
AND THE UPPER LOW PUSHES INTO THE PIEDMONT...BUT IS EXPECTED TO
REMAIN SCATTERED. SHOWERS HAVE LIMITED WHAT LITTLE INSTABILITY THERE
WAS...BUT TEMPS REMAIN IN THE MID 70S ACROSS NE NC. RAP GUIDANCE
INDICATES MLCAPE VALUES AROUND 500 J/KG. WILL KEEP MENTION OF CHANCE
THUNDER WITH LIKELY POPS. PRECIP BEGINS TO TAPER OFF INLAND THIS
EVENING AS THE COLD FRONT APPROACHES. EXPECT ONLY SCATTERED SHOWERS
ALONG THE FRONT AS IT REACHES THE AREA AROUND MIDNIGHT. YET ANOTHER
WAVE CURRENTLY ASSOCIATED WITH PRECIP OVER GA/SC IS PROGGED TO LIFT
INTO THE SE LOCAL AREA OVERNIGHT. THE ADDED LIFT FROM THE
APPROACHING UPPER LOW AND COLD FRONT WILL ENHANCE PRECIP ACROSS THE
SE VA/NE NC AGAIN. LIKELY POPS PREVAIL ALONG THE COAST THRU THE
OVERNIGHT.
MILD TEMPS EXPECTED OVERNIGHT WITH CLOUDS/PRECIP. LOWS GENERALLY IN
THE MID/UPPER 50S INLAND TO LOW 60S SOUTHEAST.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
SFC FRONT PUSHES OFFSHORE SAT MORNING AS THE UPPER LEVEL FRONT LAGS
BEHIND. SHORTWAVE DROPS OVER THE LOCAL AREA SAT AFTERNOON...PUSHING
OFFSHORE SAT EVENING. PWATS DROP TO AOB 1 INCH SAT...BUT CROSS
SECTIONS AND BUFR SOUNDINGS INDICATE REMNANT MID LEVEL MOISTURE.
ADDED FORCING FOR ASCENT AND SHARPENING LAPSE RATES AS COLDER AIR
ALOFT ADVECTS INTO THE REGION WILL RESULT IN ONGOING CHANCES FOR
SHOWERS SAT MORNING. THE BEST CHANCES WILL BE ALONG THE COAST...BUT
STILL EXPECT LIGHT SHOWERS INLAND. MOISTURE REMAINS RATHER
SHALLOW...SO EXPECT ONLY A FEW TENTHS OF AN INCH AT BEST. NLY WINDS
INCREASE TO 10 TO 15 MPH SAT AFTERNOON WITH CLEARING SKIES NW TO SE
THRU THE AFTERNOON. MODEST CAA (AT BEST) AND MIXING WILL PUSH TEMPS
BACK INTO THE LOW/MID 70S (COOLER ALONG THE COAST).
UPPER/SFC HIGH PRESSURE BUILDS OVER THE REGION SAT NIGHT...LOCATING
OVER THE MID ATLANTIC REGION SUN. EXPECT A CLEAR/SUNNY SKY WITH
SEASONABLE TEMPERATURES. LOWS SAT NIGHT IN THE MID/UPPER 40S TO LOW
50S AND HIGHS SUN IN THE LOW 70S INLAND AND MID/UPPER 60S NEAR THE
COAST. LIGHT ONSHORE FLOW WILL RESULT IN TEMPS IN THE UPPER 50S
ALONG THE IMMEDIATE COAST. THE HIGH PUSHES OFFSHORE SUN NIGHT WITH
SLY/RETURN FLOW FORECAST INTO MONDAY. LOWS SUN NIGHT IN THE UPPER
40S TO LOW 50S. SUNNY MONDAY AND WARM AS H85 TEMPS WARM TO AROUND
12C (+1 STD DEV). THICKNESSES YIELD TEMPS IN THE LOW/MID 80S UNDER A
SUNNY SKY. HIGH CLOUDS MAY INCREASE LATE MON AS THE NEXT COLD FRONT
APPROACHES THE REGION FROM THE NW.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
HIGH PRESSURE SETTLES OFF THE SOUTHEAST COAST BY TUESDAY.
MEANWHILE...A SHORTWAVE TROUGH AND AN ASSOCIATED COLD FRONT APPROACH
FROM THE NW BY TUESDAY AFTN. TUESDAY CONTINUES TO TREND TOWARD BEING
A VERY WARM DAY WITH DEEP LAYER WSW FLOW ASSOCIATED WITH A BREAKING
DOWN UPPER RIDGE OVER THE E-CENTRAL/SERN CONUS. MODEL CONSENSUS
GENERALLY SUPPORTS 850MB TEMPERATURES OF 12-15C...WHICH WITH FULL
MIXING AND DOWNSLOPING SHOULD EASILY PUSH HIGHS TO THE LOW/MID 80S W
OF THE BAY...WITH UPPER 70S FOR THE ERN SHORE...AFTER MORNING LOWS
IN THE UPPER 50S TO LOW 60S. SKY COVER SHOULD GENERALLY BE MOSTLY
CLEAR MONDAY NIGHT...AND BECOME PARTLY SUNNY BY TUESDAY. THE TROUGH
AND COLD FRONT SWING THROUGH THE AREA TUESDAY AFTN INTO TUESDAY
NIGHT. THE MAIN FORCING ASSOCIATED WITH THE MID/UPPER SHORTWAVE
TROUGH GENERALLY PASSES N OF THE LOCAL AREA...AND DEEP LAYER RH
DIMINISHES AS THE FEATURE PASSES OVER THE LOCAL AREA SO FORECAST
POPS FOR SHOWERS/TSTMS REMAIN ~20%...WITH A STRIP OF 30% ACROSS THE
FAR N...AND 40% FOR THE LOWER MD ERN SHORE. HIGH PRESSURE BUILDS IN
FROM THE N WEDNESDAY...AND SLIDES OFFSHORE THURSDAY. HIGHS WEDNESDAY
SHOULD DROP BACK TO THE MID/UPPER 60S NE...TO THE MID/UPPER 70S
FARTHER INLAND...AND THEN TREND UPWARD THURSDAY INTO THE MID 70S TO
LOW 80S AS THE HIGH SLIDES OFFSHORE. LOWS SHOULD GENERALLY BE IN THE
50S. A WEAK COLD FRONT SWINGS ACROSS THE AREA LATER IN THE WEEK WITH
ONLY A MINIMAL CHC FOR SHOWERS/TSTMS.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
CONVECTION HAS DEVELOPED THIS AFTERNOON IN THE WARM MOIST
SOUTHERLY FLOW AHEAD OF A COLD FRONT...THAT IS MOVING THROUGH
EASTERN OH/KY AT 18Z. THE MAIN BAND OF CONVECTION HAS MOVED
THROUGH RIC AND IS NOW IMPACTING THE DELMARVA AND AREAS FURTHER
SOUTH. BEHIND THIS BAND OF CONVECTION MORE SHOWERS ARE
POSSIBLE...BUT ARE NOT EXPECTING TO SEE THUNDER FOR RIC. ONCE THE
MAIN BAND CLEARS THROUGH SBY BY 20Z...AGAIN COULD SEE MORE SHOWERS
BUT THE BETTER LIFT AND INSTABILITY WILL THEN SETTLE TO THE SOUTH.
WITH THE CONVECTION EXPECT TO SEE BRIEF PERIODS OF MVFR TO IFR
CONDITIONS WITH MAINLY MVFR TO VFR CONDITIONS IN THE SHOWERS.
THERE IS ALSO A SHORTWAVE TROUGH IN THE SOUTHERN STREAM THAT IS
SLIDING ACROSS AL/GA. THIS WAVE WILL GET PULLED NORTHWARD AHEAD OF
THE NORTHERN STREAM TROUGH TONIGHT AND WILL KEEP THE THREAT FOR
RAIN/STORMS ON GOING THROUGH THE EVENING INTO THE OVERNIGHT HOURS
FOR THE VA TIDEWATER AND NERN NC. AGAIN EXPECT MVFR TO IFR
CONDITIONS IN THE SHOWERS/THUNDERSTORMS.
AFTER 6Z...EXPECT THE BEST FORCING TO MOVE OFF THE COAST AND WITH
THE WINDS EXPECTED TO WEAKEN...WILL SEE A VERY MOIST ATMOSPHERE
WILL LITTLE STIRRING...WHICH SHOULD ALLOW LOW STRATUS TO FORM WITH
SOME MINOR FOG...SO HAVE A PERIOD OF MVFR VIS/IFR CEILINGS UNTIL
THE FRONT CROSSES THE AREA BETWEEN ABOUT 10Z AND 15Z SATURDAY.
ONCE THE FRONT CLEARS AND THE WINDS START TO PICK UP FROM THE
NORTHWEST...EXPECT TO SEE IMPROVING CEILINGS AND VISIBILITIES AS
DRIER AIR MOVES IN FROM THE NORTHWEST. ANY LINGERING SHOWERS WITH
THE UPPER LOW ARE EXPECT TO IMPACT THE DELMARVA LOCATIONS SATURDAY
AFTERNOON WITH SOME MVFR LEVEL SHOWERS.
OUTLOOK SAT NIGHT THROUGH WEDNESDAY...HIGH PRESSURE RETURNS SAT
NIGHT THROUGH MONDAY NIGHT WITH MAINLY VFR CONDITIONS EXPECTED. A
COLD FRONT WILL SLIDE THROUGH FROM THE NORTH LATE ON TUESDAY...BUT
LOOKS MOISTURE STARVED. HIGH PRESSURE BUILDS IN AGAIN ON
WEDNESDAY. THROUGH THE OUTLOOK PERIOD....EXPECT MAINLY VFR
CONDITIONS.
&&
.MARINE...
HIGH PRESSURE IS SITUATED WELL OFFSHORE THIS AFTN...WITH A
COLD PUSHING TOWARD THE WRN SLOPES OF THE APPALACHIANS. MOISTURE
AHEAD OF THE FRONT HAS TRIGGERED SHOWERS/TSTMS ACROSS THE MARINE
AREA THIS AFTN...WITH A FEW CELLS PRODUCING WIND GUSTS TO 30-40KT.
THE COLD FRONT SLOWLY APPROACHES FROM THE W TONIGHT...AND PUSHES
THROUGH THE AREA SATURDAY MORNING...WITH A SUBSEQUENT NORTHERLY
SURGE SATURDAY AFTN...WITH A SECONDARY SURGE SATURDAY EVENING
THROUGH THE OVERNIGHT HOURS. LOW-END SCA CONDITIONS ARE EXPECTED
OVER THE BAY WITH A 15-20KT N WIND...LIKELY IN TWO SURGES...ONE
SATURDAY AFTN...AND THE OTHER LATER SATURDAY EVENING THROUGH THE
OVERNIGHT HOURS. AN SCA FLAG HAS BEEN RAISED FOR THE BAY TO ACCOUNT
FOR THIS. THE OCEAN IS GENERALLY EXPECTED TO REMAIN SUB-
SCA...ALTHOUGH SEAS COULD BRIEFLY REACH ~5FT OFF THE CURRITUCK OUTER
BANKS LATER SATURDAY NIGHT INTO EARLY SUNDAY AS THE WIND BECOMES
MORE NNE. HIGH PRESSURE BUILDS OVER THE AREA SUNDAY...SLIDES
OFFSHORE MONDAY...AND SETTLES OFF THE SOUTHEAST COAST TUESDAY. SEAS
GENERALLY AVERAGE 2-4FT...WITH 2-3FT WAVES IN THE BAY. ANOTHER COLD
FRONT CROSSES THE AREA TUESDAY NIGHT INTO WEDNESDAY.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM SATURDAY TO 7 AM EDT SUNDAY FOR
ANZ632-634.
SMALL CRAFT ADVISORY FROM 1 PM SATURDAY TO 4 AM EDT SUNDAY FOR
ANZ630-631.
&&
$$
SYNOPSIS...SAM
NEAR TERM...SAM
SHORT TERM...SAM
LONG TERM...AJZ
AVIATION...ESS
MARINE...AJZ
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
241 PM EDT FRI APR 22 2016
.SYNOPSIS...
A COLD FRONT APPROACHES FROM THE WEST TODAY. THE COLD FRONT PUSHES
ACROSS THE AREA AND OFF THE COAST TONIGHT INTO EARLY SATURDAY
MORNING. AN UPPER LEVEL DISTURBANCE WILL DROP THROUGH THE REGION
DURING SATURDAY. HIGH PRESSURE RETURNS FOR SATURDAY NIGHT THROUGH
MONDAY. THE NEXT COLD FRONT DROPS ACROSS THE REGION TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST REGIONAL RADAR MOSAIC DEPICTS AN AREA OF SHOWERS LIFTING NEWD
INTO THE ERN VA PIEDMONT LATE THIS MORNING. THIS WELL IN ADVANCE OF
THE COLD FRONT...CURRENTLY LOCATED OVER THE OH VALLEY. AREA OF
SHOWERS MATCHES UP WELL WITH ISENTROPIC LIFT IN THE 300K SFC. MODEST
HEIGHT FALLS AND INCREASING WINDS ALOFT HAVE PROVIDED FORCING FOR
ASCENT AS THE UPPER RIDGE AXIS HAS PUSHED OFFSHORE. H85 MOISTURE
TRANSPORT HAS ADVECTED PWATS OF 1.0 TO 1.25 INCHES INTO THE REGION.
FOLLOWING HI-RES GUIDANCE (WHICH HAS VERIFIED WELL SO FAR)...EXPECT
PRECIP TO LIFT INTO CENTRAL VA AROUND NOON AND THEN POINTS EWD THRU
THE AFTERNOON. RAP SBCAPE DEPICTS LIMITED INSTABILITY OVER THE
REGION THIS MORNING...SO ONLY ANTICIPATED ISOLATED THUNDER THIS
MORNING.
BETTER FORCING ARRIVES THIS AFTERNOON AS PWATS INCREASE TO AROUND
1.2 TO 1.45 INCHES (+1 STD DEV). NAM/RAP/SREF MLCAPE REMAINS
MARGINAL AT BEST...GENERALLY AOB 750 J/KG. LAPSE RATES ALSO REMAIN
MODEST AS THE COLDEST AIR ALOFT REMAINS WEST OF THE REGION
ASSOCIATED WITH THE UPPER LEVEL FRONT. EFF SHEAR ALSO AOB 30 KT.
WITH THAT SAID...ONLY EXPECT EMBEDDED/UNORGANIZED THUNDERSTORMS. HI-
RES GUIDANCE AND NAM12 300K KEEPS THE BEST LOW LEVEL FORCING OVER
THE SOUTHEAST HALF OF THE FORECAST AREA...WHERE HIGHEST POPS WILL BE
MAINTAINED. HOWEVER...EXPECT MORE SCATTERED SHOWER ACTIVITY ACROSS
THE NW...SO HAVE TRIMMED POPS BACK INTO CHANCE RANGE. THE FRONT
PUSHES ACROSS THE REGION LATE TODAY AS ADDITIONAL UPPER LEVEL
PERTURBATIONS LIFT INTO THE REGION. EXPECT ADDITIONAL COVERAGE LATE
AFTERNOON ACROSS THE SOUTHEAST HALF OF THE LOCAL AREA. WILL RETAIN
LIKELY POPS...WITH THE NW POSSIBLY SEEING A DRYING TREND. BETTER
INSTABILITY EXPECTED MID-LATE AFTERNOON (ALBEIT STILL MARGINAL)
ACROSS THE SE...SO PERHAPS A BETTER CHANCE TO SEE THUNDER.
RETURN FLOW AND BREAKS IN THE CLOUDS WILL PUSH TEMPS INTO THE UPPER
70S TO NEAR 80 EAST OF INTERSTATE 95 (COOLER ALONG THE COAST AND
BAY). TEMPS WEST OF INTERSTATE 95 WILL LEVEL OFF IN THE LOW/MID 70S
LATE THIS MORNING THRU MID AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
WITH THE UPR LO/TROF LAGGING BEHIND THE COLD FRONT...AND PLENTY OF
LO LEVEL MOISTURE/LIFT IN PLACE...NOW HAVE LIKELY POPS EVERYWHERE
INTO TNGT. HAVE ALSO KEPT SLGT CHC OF THUNDER. LATER TNGT INTO
SAT MORNG...BULK OF PCPN WILL MOVE EWRD AND OFF THE CST AS THE UPR
LO/TROF PUSHES THE COLD FRONT ACRS THE AREA AND OFFSHR. PWATS
CLIMB TO 1.25 TO 1.5 INCHES...WHICH MAY RESULT IN PERIODS OF
MODERATE TO LOCALLY HEAVY RAINFALL. HOWEVER...QPF AMTS THRU TNGT
WILL GENERALLY RANGE FM ARND .30 INCH ACRS THE N TO NEAR .60 INCH
ACRS THE S. LOWS TNGT IN THE MID 50S TO LWR 60S.
MODEL TRENDS CONTINUE TO LINGER MID LEVEL MOISTURE TO GO ALONG
WITH THE STRONG DYNAMICS PROVIDED BY THE UPR LO DROPPING THRU THE
REGION THRU SAT AFTN. WILL HOLD ONTO SOLID CHC POPS THRU LATE
MORNG INLAND FOR SCTD SHOWERS...AND ALONG SE VA/NE NC THRU SAT
AFTN. CLOUDY CONDITIONS BECOME PARTLY CLOUDY INLAND SAT
AFTN...BUT REMAIN MOSTLY CLOUDY ALNG THE CST. TRENDED TOWARD THE
COOLER SIDE OF THE MOS GUIDANCE...DUE TO CLOUD COVER AND MODEST
CAA...BUT TEMPS REMAIN SEASONABLE IN THE UPR 60S TO MID 70S. N
WINDS GENERALLY 10 TO 15 MPH WITH GUSTS OF 20 TO 25 MPH. TROF AXIS
PUSHES WELL OFFSHORE SAT NGT...WITH DRY CONDITIONS FCST ACRS THE
AREA. LOWS IN THE MID TO UPR 40S INLAND...TO THE LWR 50S NEAR THE
CST UNDER A CLEAR OR MOSTLY CLEAR SKY. HI PRES BLDS INTO THE NE
U.S. AND TWD NEW ENGLAND SAT NGT...THEN SLIDES TO JUST OFF THE NE
U.S. AND MID ATLC CST BY 00Z MON. THE RESULT WILL BE ONGOING DRY
CONDITIONS ON SUN UNDER A MOSTLY SNY SKY. HI TEMPS WILL RANGE FM
THE MID 60S TO LWR 70S OVR MOST OF THE REGION..
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE SLIDES FARTHER OFFSHORE SUNDAY NIGHT AND MONDAY...AND
SETTLES OFF THE SOUTHEAST COAST BY TUESDAY. MEANWHILE...A SHORTWAVE
TROUGH AND AN ASSOCIATED COLD FRONT APPROACH FROM THE NW BY TUESDAY
AFTN. MONDAY AND TUESDAY ARE TRENDING TOWARD BEING VERY WARM DAYS
WITH DEEP LAYER WSW FLOW ASSOCIATED WITH A BREAKING DOWN UPPER RIDGE
OVER THE E-CENTRAL/SERN CONUS. MODEL CONSENSUS GENERALLY SUPPORTS
850MB TEMPERATURES OF 12-15C...WHICH WITH FULL MIXING AND
DOWNSLOPING SHOULD EASILY PUSH HIGHS TO 80-85F W OF THE BAY...WITH
UPPER 70S FOR THE ERN SHORE. LOWS SUNDAY NIGHT SHOULD BE IN THE
LOW/MID 50S...WITH 55-60F MONDAY NIGHT. SKY COVER SHOULD GENERALLY
BE MOSTLY CLEAR/SUNNY SUNDAY NIGHT...MONDAY INTO MONDAY NIGHT...AND
BECOME PARTLY SUNNY TUESDAY. THE TROUGH AND COLD FRONT SWING THROUGH
THE AREA TUESDAY AFTN INTO TUESDAY NIGHT. THE MAIN FORCING
ASSOCIATED WITH THE MID/UPPER SHORTWAVE TROUGH GENERALLY PASSES N OF
THE LOCAL AREA...AND DEEP LAYER RH DIMINISHES AS THE FEATURE PASSES
OVER THE LOCAL AREA SO FORECAST POPS ARE ONLY 20%...WITH A NARROW
STRIP OF 30% ACROSS THE FAR N. HIGH PRESSURE BUILDS IN FROM THE N
WEDNESDAY...AND SLIDES OFFSHORE LATER IN THE WEEK. HIGHS WEDNESDAY
SHOULD DROP BACK TO THE MID/UPPER 60S NE...TO THE MID/UPPER 70S
FARTHER INLAND...AND THEN TREND UPWARD INTO THURSDAY AS THE HIGH
SLIDES OFFSHORE. LOWS SHOULD GENERALLY BE IN THE 50S.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
CONVECTION HAS DEVELOPED THIS AFTERNOON IN THE WARM MOIST
SOUTHERLY FLOW AHEAD OF A COLD FRONT...THAT IS MOVING THROUGH
EASTERN OH/KY AT 18Z. THE MAIN BAND OF CONVECTION HAS MOVED
THROUGH RIC AND IS NOW IMPACTING THE DELMARVA AND AREAS FURTHER
SOUTH. BEHIND THIS BAND OF CONVECTION MORE SHOWERS ARE
POSSIBLE...BUT ARE NOT EXPECTING TO SEE THUNDER FOR RIC. ONCE THE
MAIN BAND CLEARS THROUGH SBY BY 20Z...AGAIN COULD SEE MORE SHOWERS
BUT THE BETTER LIFT AND INSTABILITY WILL THEN SETTLE TO THE SOUTH.
WITH THE CONVECTION EXPECT TO SEE BRIEF PERIODS OF MVFR TO IFR
CONDITIONS WITH MAINLY MVFR TO VFR CONDITIONS IN THE SHOWERS.
THERE IS ALSO A SHORTWAVE TROUGH IN THE SOUTHERN STREAM THAT IS
SLIDING ACROSS AL/GA. THIS WAVE WILL GET PULLED NORTHWARD AHEAD OF
THE NORTHERN STREAM TROUGH TONIGHT AND WILL KEEP THE THREAT FOR
RAIN/STORMS ON GOING THROUGH THE EVENING INTO THE OVERNIGHT HOURS
FOR THE VA TIDEWATER AND NERN NC. AGAIN EXPECT MVFR TO IFR
CONDITIONS IN THE SHOWERS/THUNDERSTORMS.
AFTER 6Z...EXPECT THE BEST FORCING TO MOVE OFF THE COAST AND WITH
THE WINDS EXPECTED TO WEAKEN...WILL SEE A VERY MOIST ATMOSPHERE
WILL LITTLE STIRRING...WHICH SHOULD ALLOW LOW STRATUS TO FORM WITH
SOME MINOR FOG...SO HAVE A PERIOD OF MVFR VIS/IFR CEILINGS UNTIL
THE FRONT CROSSES THE AREA BETWEEN ABOUT 10Z AND 15Z SATURDAY.
ONCE THE FRONT CLEARS AND THE WINDS START TO PICK UP FROM THE
NORTHWEST...EXPECT TO SEE IMPROVING CEILINGS AND VISIBILITIES AS
DRIER AIR MOVES IN FROM THE NORTHWEST. ANY LINGERING SHOWERS WITH
THE UPPER LOW ARE EXPECT TO IMPACT THE DELMARVA LOCATIONS SATURDAY
AFTERNOON WITH SOME MVFR LEVEL SHOWERS.
OUTLOOK SAT NIGHT THROUGH WEDNESDAY...HIGH PRESSURE RETURNS SAT
NIGHT THROUGH MONDAY NIGHT WITH MAINLY VFR CONDITIONS EXPECTED. A
COLD FRONT WILL SLIDE THROUGH FROM THE NORTH LATE ON TUESDAY...BUT
LOOKS MOISTURE STARVED. HIGH PRESSURE BUILDS IN AGAIN ON
WEDNESDAY. THROUGH THE OUTLOOK PERIOD....EXPECT MAINLY VFR
CONDITIONS.
&&
.MARINE...
TOUGH CALL WRT SCA HEADLINES TODAY AS ANY CRITERIA THAT MAY BE
MET WILL BE MINIMAL AT BEST. WILL KEEP SUSTAINED WINDS IN THE BAY
CAPPED AT 15 KT FOR NOW...ALTHOUGH OCNL GUSTS TO 20 KTS WILL BE
POSSIBLE THROUGH LATE AFTERNOON. SEAS CRNTLY 3-5 FT ACROSS MD
COASTAL WATERS (3 FT NEAR SHORE BUT 5 FT NEAR 44009) SO HAVE
ISSUED A SCA ACROSS THE MD COASTAL WATERS THROUGH 14Z WITH THE
EXPECTATION THAT SEAS OUT NEAR 20 NM DROP BELOW 5 FEET LATER THIS
MORNING. ELECTED NOT TO HAVE ANY HEADLINES FOR THE CHES BAY AND
WILL DEFER TO THE DAY SHIFT IF WINDS BECOME HIGHER THAN EXPECTED.
COLD FRONT PROGGED ACROSS THE MARINE AREA SAT MORNING. LATEST
GUIDANCE SHOWING TWO CAA SURGES...ONE SAT AFTERNOON AND ANOTHER ONE
SAT NIGHT. THE SAT AFTERNOON ONE APPEARS TO BE MARGINAL AT BEST FOR
ANY SCA HEADLINE SO WILL KEEP WINDS CAPPED AT 15 KTS ATTM. THE
SECOND CAA SURGE SAT NIGHT APPEARS TO BE A BIT STRONGER WITH WINDS
INCREASING INTO THE SCA RANGE FOR A FEW HOURS OVER THE CHES BAY.
HIGH PRESSURE BUILDS OVER THE AREA SUNDAY...SLIDES OFFSHORE
MONDAY...AND SETTLES OFF THE SOUTHEAST COAST TUESDAY.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SAM/TMG
NEAR TERM...SAM
SHORT TERM...SAM/TMG
LONG TERM...AJZ
AVIATION...ESS
MARINE...MPR
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1108 AM EDT FRI APR 22 2016
.SYNOPSIS...
A COLD FRONT APPROACHES FROM THE WEST TODAY. THE COLD FRONT PUSHES
ACROSS THE AREA AND OFF THE COAST TONIGHT INTO EARLY SATURDAY
MORNING. AN UPPER LEVEL DISTURBANCE WILL DROP THROUGH THE REGION
DURING SATURDAY. HIGH PRESSURE RETURNS FOR SATURDAY NIGHT THROUGH
MONDAY. THE NEXT COLD FRONT DROPS ACROSS THE REGION TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST REGIONAL RADAR MOSAIC DEPICTS AN AREA OF SHOWERS LIFTING NEWD
INTO THE ERN VA PIEDMONT LATE THIS MORNING. THIS WELL IN ADVANCE OF
THE COLD FRONT...CURRENTLY LOCATED OVER THE OH VALLEY. AREA OF
SHOWERS MATCHES UP WELL WITH ISENTROPIC LIFT IN THE 300K SFC. MODEST
HEIGHT FALLS AND INCREASING WINDS ALOFT HAVE PROVIDED FORCING FOR
ASCENT AS THE UPPER RIDGE AXIS HAS PUSHED OFFSHORE. H85 MOISTURE
TRANSPORT HAS ADVECTED PWATS OF 1.0 TO 1.25 INCHES INTO THE REGION.
FOLLOWING HI-RES GUIDANCE (WHICH HAS VERIFIED WELL SO FAR)...EXPECT
PRECIP TO LIFT INTO CENTRAL VA AROUND NOON AND THEN POINTS EWD THRU
THE AFTERNOON. RAP SBCAPE DEPICTS LIMITED INSTABILITY OVER THE
REGION THIS MORNING...SO ONLY ANTICIPATED ISOLATED THUNDER THIS
MORNING.
BETTER FORCING ARRIVES THIS AFTERNOON AS PWATS INCREASE TO AROUND
1.2 TO 1.45 INCHES (+1 STD DEV). NAM/RAP/SREF MLCAPE REMAINS
MARGINAL AT BEST...GENERALLY AOB 750 J/KG. LAPSE RATES ALSO REMAIN
MODEST AS THE COLDEST AIR ALOFT REMAINS WEST OF THE REGION
ASSOCIATED WITH THE UPPER LEVEL FRONT. EFF SHEAR ALSO AOB 30 KT.
WITH THAT SAID...ONLY EXPECT EMBEDDED/UNORGANIZED THUNDERSTORMS. HI-
RES GUIDANCE AND NAM12 300K KEEPS THE BEST LOW LEVEL FORCING OVER
THE SOUTHEAST HALF OF THE FORECAST AREA...WHERE HIGHEST POPS WILL BE
MAINTAINED. HOWEVER...EXPECT MORE SCATTERED SHOWER ACTIVITY ACROSS
THE NW...SO HAVE TRIMMED POPS BACK INTO CHANCE RANGE. THE FRONT
PUSHES ACROSS THE REGION LATE TODAY AS ADDITIONAL UPPER LEVEL
PERTURBATIONS LIFT INTO THE REGION. EXPECT ADDITIONAL COVERAGE LATE
AFTERNOON ACROSS THE SOUTHEAST HALF OF THE LOCAL AREA. WILL RETAIN
LIKELY POPS...WITH THE NW POSSIBLY SEEING A DRYING TREND. BETTER
INSTABILITY EXPECTED MID-LATE AFTERNOON (ALBEIT STILL MARGINAL)
ACROSS THE SE...SO PERHAPS A BETTER CHANCE TO SEE THUNDER.
RETURN FLOW AND BREAKS IN THE CLOUDS WILL PUSH TEMPS INTO THE UPPER
70S TO NEAR 80 EAST OF INTERSTATE 95 (COOLER ALONG THE COAST AND
BAY). TEMPS WEST OF INTERSTATE 95 WILL LEVEL OFF IN THE LOW/MID 70S
LATE THIS MORNING THRU MID AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
WITH THE UPR LO/TROF LAGGING BEHIND THE COLD FRONT...AND PLENTY OF
LO LEVEL MOISTURE/LIFT IN PLACE...NOW HAVE LIKELY POPS EVERYWHERE
INTO TNGT. HAVE ALSO KEPT SLGT CHC OF THUNDER. LATER TNGT INTO
SAT MORNG...BULK OF PCPN WILL MOVE EWRD AND OFF THE CST AS THE UPR
LO/TROF PUSHES THE COLD FRONT ACRS THE AREA AND OFFSHR. PWATS
CLIMB TO 1.25 TO 1.5 INCHES...WHICH MAY RESULT IN PERIODS OF
MODERATE TO LOCALLY HEAVY RAINFALL. HOWEVER...QPF AMTS THRU TNGT
WILL GENERALLY RANGE FM ARND .30 INCH ACRS THE N TO NEAR .60 INCH
ACRS THE S. LOWS TNGT IN THE MID 50S TO LWR 60S.
MODEL TRENDS CONTINUE TO LINGER MID LEVEL MOISTURE TO GO ALONG
WITH THE STRONG DYNAMICS PROVIDED BY THE UPR LO DROPPING THRU THE
REGION THRU SAT AFTN. WILL HOLD ONTO SOLID CHC POPS THRU LATE
MORNG INLAND FOR SCTD SHOWERS...AND ALONG SE VA/NE NC THRU SAT
AFTN. CLOUDY CONDITIONS BECOME PARTLY CLOUDY INLAND SAT
AFTN...BUT REMAIN MOSTLY CLOUDY ALNG THE CST. TRENDED TOWARD THE
COOLER SIDE OF THE MOS GUIDANCE...DUE TO CLOUD COVER AND MODEST
CAA...BUT TEMPS REMAIN SEASONABLE IN THE UPR 60S TO MID 70S. N
WINDS GENERALLY 10 TO 15 MPH WITH GUSTS OF 20 TO 25 MPH. TROF AXIS
PUSHES WELL OFFSHORE SAT NGT...WITH DRY CONDITIONS FCST ACRS THE
AREA. LOWS IN THE MID TO UPR 40S INLAND...TO THE LWR 50S NEAR THE
CST UNDER A CLEAR OR MOSTLY CLEAR SKY. HI PRES BLDS INTO THE NE
U.S. AND TWD NEW ENGLAND SAT NGT...THEN SLIDES TO JUST OFF THE NE
U.S. AND MID ATLC CST BY 00Z MON. THE RESULT WILL BE ONGOING DRY
CONDITIONS ON SUN UNDER A MOSTLY SNY SKY. HI TEMPS WILL RANGE FM
THE MID 60S TO LWR 70S OVR MOST OF THE REGION..
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE SLIDES FARTHER OFFSHORE SUNDAY NIGHT AND MONDAY...AND
SETTLES OFF THE SOUTHEAST COAST BY TUESDAY. MEANWHILE...A SHORTWAVE
TROUGH AND AN ASSOCIATED COLD FRONT APPROACH FROM THE NW BY TUESDAY
AFTN. MONDAY AND TUESDAY ARE TRENDING TOWARD BEING VERY WARM DAYS
WITH DEEP LAYER WSW FLOW ASSOCIATED WITH A BREAKING DOWN UPPER RIDGE
OVER THE E-CENTRAL/SERN CONUS. MODEL CONSENSUS GENERALLY SUPPORTS
850MB TEMPERATURES OF 12-15C...WHICH WITH FULL MIXING AND
DOWNSLOPING SHOULD EASILY PUSH HIGHS TO 80-85F W OF THE BAY...WITH
UPPER 70S FOR THE ERN SHORE. LOWS SUNDAY NIGHT SHOULD BE IN THE
LOW/MID 50S...WITH 55-60F MONDAY NIGHT. SKY COVER SHOULD GENERALLY
BE MOSTLY CLEAR/SUNNY SUNDAY NIGHT...MONDAY INTO MONDAY NIGHT...AND
BECOME PARTLY SUNNY TUESDAY. THE TROUGH AND COLD FRONT SWING THROUGH
THE AREA TUESDAY AFTN INTO TUESDAY NIGHT. THE MAIN FORCING
ASSOCIATED WITH THE MID/UPPER SHORTWAVE TROUGH GENERALLY PASSES N OF
THE LOCAL AREA...AND DEEP LAYER RH DIMINISHES AS THE FEATURE PASSES
OVER THE LOCAL AREA SO FORECAST POPS ARE ONLY 20%...WITH A NARROW
STRIP OF 30% ACROSS THE FAR N. HIGH PRESSURE BUILDS IN FROM THE N
WEDNESDAY...AND SLIDES OFFSHORE LATER IN THE WEEK. HIGHS WEDNESDAY
SHOULD DROP BACK TO THE MID/UPPER 60S NE...TO THE MID/UPPER 70S
FARTHER INLAND...AND THEN TREND UPWARD INTO THURSDAY AS THE HIGH
SLIDES OFFSHORE. LOWS SHOULD GENERALLY BE IN THE 50S.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
LATEST SFC OBS / SAT LOOP INDICATING A QUICK INCREASE IN BKN SC
DECK BETWEEN 1.5-3K FT THIS MORNING. SHOWERS THEN MOVE SW TO NE
AFTER 16Z AS A SHORTWAVE MOVES ACROSS THE REGION WELL AHEAD OF
THE APPROACHING COLD FRONT. THUNDER POSSIBLE BUT WAS KEPT OUT OF
THIS FORECAST ISSUANCE SINCE ANY THUNDER NOT EXPECTED UNTIL AFTER
18Z. MOST LIKELY AREAS TO SEE TSTMS WILL BE ALONG AND SOUTH OF I64
WITH BEST TIMING BETWEEN 18Z-00Z. SW WIND GUST BETWEEN 15-20 KTS
AHEAD OF ANY SHOWER WITH HIGHER GUSTS POSSIBLE IN ANY TSTMS.
MODEL GUIDANCE SUPPORTS IFR CIGS DEVELOPING BY OR SHORTLY AFTER
00Z ALONG WITH REDUCED VSBYS IN RAIN/SHOWERS WITH AREAS OF FOG
LINGERING THROUGH THE NIGHT. THE COLD FRONT MOVES OFF THE COAST
EARLY SAT. TRAILING CLOSED UPPER LOW WILL CAUSE LAPSE RATES TO
INCREASE WHICH WILL CONTINUE THE POSSIBILITY FOR MVFR CIGS AND
SHOWER OR TSTM DEVELOPMENT INTO SAT. DRIER AIR AND VFR CONDITIONS
RETURN LATE SAT NIGHT.
&&
.MARINE...
TOUGH CALL WRT SCA HEADLINES TODAY AS ANY CRITERIA THAT MAY BE
MET WILL BE MINIMAL AT BEST. WILL KEEP SUSTAINED WINDS IN THE BAY
CAPPED AT 15 KT FOR NOW...ALTHOUGH OCNL GUSTS TO 20 KTS WILL BE
POSSIBLE THROUGH LATE AFTERNOON. SEAS CRNTLY 3-5 FT ACROSS MD
COASTAL WATERS (3 FT NEAR SHORE BUT 5 FT NEAR 44009) SO HAVE
ISSUED A SCA ACROSS THE MD COASTAL WATERS THROUGH 14Z WITH THE
EXPECTATION THAT SEAS OUT NEAR 20 NM DROP BELOW 5 FEET LATER THIS
MORNING. ELECTED NOT TO HAVE ANY HEADLINES FOR THE CHES BAY AND
WILL DEFER TO THE DAY SHIFT IF WINDS BECOME HIGHER THAN EXPECTED.
COLD FRONT PROGGED ACROSS THE MARINE AREA SAT MORNING. LATEST
GUIDANCE SHOWING TWO CAA SURGES...ONE SAT AFTERNOON AND ANOTHER ONE
SAT NIGHT. THE SAT AFTERNOON ONE APPEARS TO BE MARGINAL AT BEST FOR
ANY SCA HEADLINE SO WILL KEEP WINDS CAPPED AT 15 KTS ATTM. THE
SECOND CAA SURGE SAT NIGHT APPEARS TO BE A BIT STRONGER WITH WINDS
INCREASING INTO THE SCA RANGE FOR A FEW HOURS OVER THE CHES BAY.
HIGH PRESSURE BUILDS OVER THE AREA SUNDAY...SLIDES OFFSHORE
MONDAY...AND SETTLES OFF THE SOUTHEAST COAST TUESDAY.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SAM/TMG
NEAR TERM...SAM
SHORT TERM...SAM/TMG
LONG TERM...AJZ
AVIATION...MPR
MARINE...MPR
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
123 AM EDT FRI APR 22 2016
.SYNOPSIS...
HIGH PRESSURE REMAINS OVER THE WESTERN ATLANTIC TONIGHT. A COLD
FRONT WILL APPROACH FROM THE WEST FRIDAY...PUSHING OFF THE COAST
EARLY SATURDAY MORNING. AN UPPER LEVEL DISTURBANCE DROPS OVER THE
REGION SATURDAY. HIGH PRESSURE RETURNS FOR SATURDAY NIGHT INTO
MONDAY. THE NEXT COLD FRONT PUSHES ACROSS THE REGION TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
FORECAST UPDATED BASED ON LATEST RADAR TRENDS AND HIRES MODEL
GUIDANCE...MAIN CHANGES WERE TO DROP ANY CHC OF PCPN THIS EVENG
AND DELAY POPS A BIT FRI MORNG.
PREVIOUS DISCUSSION...
LATEST REGIONAL RADAR MOSAIC DEPICTS ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS EXTENDING FROM SE NC INTO CENTRAL NC
THIS AFTERNOON. BASED ON LATEST SFC OBS...THE WARM FRONT HAS
LIFTED INTO THE LOCAL AREA...WITH BETTER DESTABILIZATION SOUTH OF
THE LOCAL AREA. EXPECT THE BETTER INSTABILITY TO REMAIN SOUTH OF
THE REGION...BUT HI-RES GUIDANCE CONTINUES TO INDICATE THE
POTENTIAL FOR ISOLATED TO WIDELY SCATTERED SHOWERS LIFTING INTO
SRN VA AND NE NC THRU LATE THIS AFTERNOON. NAM12 300K SURFACES
BACK UP THIS SCENARIO...INDICATING LOW LEVEL LIFT EVEN UNDER THE
UPPER LEVEL RIDGE LOCATED OVER THE ERN CONUS. RAP SOUNDINGS
INDICATE MODEST CAPE EXTENDING INTO THE MIXED PHASE LAYER...SO
WILL MENTION SLIGHT CHANCE FOR THUNDER. ANY SHOWERS THAT DO
DEVELOP WILL DISSIPATE EARLY EVENING WITH THE LOSS OF DAYTIME
HEATING.
TEMPS HAVE WARMED INTO THE MID/UPPER 70S...WITH A FEW LOCALES
HITTING 80 ACROSS THE PIEDMONT INTO CENTRAL VA. SOUTH WINDS AROUND
10 MPH TONIGHT ALONG WITH A PARTLY CLOUDY SKY WILL RESULT IN MILD
OVERNIGHT TEMPS. LOWS GENERALLY IN THE LOW 60S (~+1 STD DEV OR 10-12
DEGS ABOVE NORMAL).
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY/...
GENERAL MODEL TRENDS CONTINUE TO SLOW THE UPPER SYSTEM SLIGHTLY AND
DIG IT FARTHER SOUTH AND WEST THROUGH FRIDAY NIGHT. CURRENT NATIONAL
RADAR TRENDS OVER THE OH VALLEY...DEPICT RATHER UNORGANIZED
CONVECTION ASSOCIATED WITH THE UPPER LOW. THE UPPER LOW PUSHES INTO
THE TN VALLEY AS A STRONG UPPER LOW DEEPENS OVER ERN CANADA. THE
FRONT REACHES THE ERN VA PIEDMONT LATE FRIDAY INTO EARLY FRI
EVENING. LEAD SHORTWAVE ENERGY ROUNDS THE BASE OF THE UPPER
TROUGH...LIFTING INTO THE REGION FRI AFTERNOON AHEAD OF THE MAIN
TROUGH ENERGY. RETURN FLOW ADVECTS DEEPER MOISTURE INTO THE
REGION...WITH H85 FLOW COMING IN FROM THE GULF STREAM. POPS RAMP UP
OVER THE PIEDMONT MID TO LATE MORNING...AND THEN POINTS EWD THROUGH
EARLY AFTERNOON. THE FAVORED AREAS FOR SHOWERS CONTINUE TO BE ALONG
AND SOUTH OF A LINE FROM FARMVILLE TO RICHMOND AND TO THE NRN
NECK/MD ERN SHORE FRI AFTERNOON AND FRIDAY EVENING. HAVE MAINTAINED
LIKELY POPS FOR THAT AREA. HAVE TRIMMED BACK POPS NORTH AND WEST OF
THIS LINE AS MODELS INDICATE SHOWER COVERAGE ASSOCIATED WITH THE
MAIN SHORTWAVE WILL BE LIMITED IN THAT REGION. THUNDERSTORM
POTENTIAL REMAINS MARGINAL DUE TO CONSIDERABLE CLOUD COVER AND
MARGINAL INSTABILITY. GIVEN THE DYNAMICS...THETA-E ADVECTION AND THE
TIME OF YEAR...WILL KEEP CHANCE MENTION OF THUNDER. SHEAR REMAINS
MODEST (AOB 30 KT)...SO EXPECT ONLY EMBEDDED THUNDER. PWATS CLIMB TO
1.25 TO 1.5 INCHES...WHICH MAY RESULT IN PERIODS OF MODERATE TO
LOCALLY HEAVY RAINFALL. HOWEVER...QPF AMOUNTS THRU FRIDAY EVENING
WILL GENERALLY RANGE FROM LESS THAN ONE QUARTER OF AN INCH ACROSS
THE NORTH UP TO ONE HALF INCH ACROSS THE SOUTH. AREA REMAINS IN WARM
SECTOR WITH RETURN FLOW PUSHING TEMPS BACK INTO THE MID/UPPER
70S...EVEN WITH CONSIDERABLE CLOUD COVER. SHORTWAVE DROPS OVER THE
CENTRAL APPALACHIANS INTO THE LOCAL AREA THRU FRI NIGHT AS THE FRONT
PUSHES OFFSHORE. WILL KEEP SOLID CHANCE POPS ALONG THE COAST THRU
THE OVERNIGHT PERIOD.
AFOREMENTIONED MODEL TRENDS MEAN LINGERING MID LEVEL MOISTURE TO
GO ALONG WITH THE STRONG DYNAMICS PROVIDED BY THE UPPER LOW DROPPING
OVER THE REGION SAT. WILL HOLD ONTO SOLID CHANCE POPS THROUGH LATE
MORNING INLAND FOR SCATTERED SHOWERS...AND ALONG THE COAST THRU SAT
AFTERNOON. CLOUDY CONDITIONS BECOME PARTLY CLOUDY INLAND SAT
AFTERNOON...BUT REMAIN MOSTLY CLOUDY ALONG THE COAST. TRENDED TOWARD
THE COOLER SIDE OF THE MOS GUIDANCE DUE TO CLOUD COVER AND MODEST
CAA...BUT TEMPS REMAIN SEASONABLE IN THE UPPER 60S/LOW 70S.
NORTH WINDS GENERALLY 10 TO 15 MPH WITH GUSTS OF 20 TO 25 MPH. TROUGH
AXIS PUSHES OFFSHORE SAT NIGHT WITH DRY CONDITIONS FORECAST ACROSS
THE AREA. LOWS IN THE MID/UPPER 40S INLAND TO LOW 50S NEAR THE COAST
UNDER A CLEAR SKY. HIGH PRESSURE BUILDS ACROSS NEW ENGLAND SAT
NIGHT...PARKING OFF THE NORTHEAST COAST SUNDAY. THE RESULT WILL BE
ONGOING DRY CONDITIONS. CAA WANES SUN...BUT LIGHT ONSHORE FLOW WILL
KEEP TEMPS IN CHECK. THICKNESSES YIELD TEMPS IN THE LOW/MID 70S
INLAND AND MID/UPPER 60S ALONG THE COAST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE SLIDES FARTHER OFFSHORE SUNDAY NIGHT AND MONDAY...AND
SETTLES OFF THE SOUTHEAST COAST BY TUESDAY. MEANWHILE...A SHORTWAVE
TROUGH AND AN ASSOCIATED COLD FRONT APPROACH FROM THE NW BY TUESDAY
AFTN. MONDAY AND TUESDAY ARE TRENDING TOWARD BEING VERY WARM DAYS
WITH DEEP LAYER WSW FLOW ASSOCIATED WITH A BREAKING DOWN UPPER RIDGE
OVER THE E-CENTRAL/SERN CONUS. MODEL CONSENSUS GENERALLY SUPPORTS
850MB TEMPERATURES OF 12-15C...WHICH WITH FULL MIXING AND
DOWNSLOPING SHOULD EASILY PUSH HIGHS TO 80-85F W OF THE BAY...WITH
UPPER 70S FOR THE ERN SHORE. LOWS SUNDAY NIGHT SHOULD BE IN THE
LOW/MID 50S...WITH 55-60F MONDAY NIGHT. SKY COVER SHOULD GENERALLY
BE MOSTLY CLEAR/SUNNY SUNDAY NIGHT...MONDAY INTO MONDAY NIGHT...AND
BECOME PARTLY SUNNY TUESDAY. THE TROUGH AND COLD FRONT SWING THROUGH
THE AREA TUESDAY AFTN INTO TUESDAY NIGHT. THE MAIN FORCING
ASSOCIATED WITH THE MID/UPPER SHORTWAVE TROUGH GENERALLY PASSES N OF
THE LOCAL AREA...AND DEEP LAYER RH DIMINISHES AS THE FEATURE PASSES
OVER THE LOCAL AREA SO FORECAST POPS ARE ONLY 20%...WITH A NARROW
STRIP OF 30% ACROSS THE FAR N. HIGH PRESSURE BUILDS IN FROM THE N
WEDNESDAY...AND SLIDES OFFSHORE LATER IN THE WEEK. HIGHS WEDNESDAY
SHOULD DROP BACK TO THE MID/UPPER 60S NE...TO THE MID/UPPER 70S
FARTHER INLAND...AND THEN TREND UPWARD INTO THURSDAY AS THE HIGH
SLIDES OFFSHORE. LOWS SHOULD GENERALLY BE IN THE 50S.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS START OFF THE FORECAST PERIOD AND WILL CONTINUE
THROUGH AT LEAST MID MORNING. SOUTH WINDS AVG 10-15 KTS WITH HIGH
AND MID LEVEL CLOUDS INCREASE ESPECIALLY AFTER 12Z.
LATEST MODEL DATA INDICATES A QUICK INCREASE IN MID LEVEL MOISTURE
BY LATE MORNING AS MVFR CIGS (BKN SC) BECOME COMMON. SHOWERS THEN
MOVE WEST TO EAST AFTER 16Z AS A SHORTWAVE MOVES ACROSS THE REGION
WELL AHEAD OF THE APPROACHING COLD FRONT. THUNDER POSSIBLE BUT
WAS KEPT OUT OF THIS FORECAST ISSUANCE SINCE ANY THUNDER NOT EXPECTED
UNTIL AFTER 18Z. MOST LIKELY AREAS TO SEE TSTMS WILL BE ALONG AND
SOUTH OF I64 WITH BEST TIMING BETWEEN 18Z-00Z. SW WIND GUST BETWEEN
15-20 KTS AHEAD OF ANY SHOWER WITH HIGHER GUSTS POSSIBLE IN ANY
TSTMS CLOSER TOWARD 00Z.
ALL MODEL GUIDANCE SUPPORTS IFR CIGS DEVELOPING BY OR SHORTLY
AFTER 00Z ALONG WITH REDUCED VSBYS IN RAIN/SHOWERS AND AREAS
OF FOG. THE COLD FRONT MOVES OFF THE COAST LATE FRI NIGHT/EARLY
SAT. TRAILING CLOSED UPPER LOW WILL CAUSE LAPSE RATES TO INCREASE
WHICH WILL CONTINUE THE POSSIBILITY FOR MVFR CIGS AND SHOWER OR
TSTM DEVELOPMENT INTO SAT. DRIER AIR AND VFR CONDITIONS RETURN
LATE SAT NIGHT.
&&
.MARINE...
WENT AHEAD AND ISSUED A MINIMAL SCA FOR THE CHES BAY THROUGH 4 AM
BASED ON THE AMOUNT OF 20 KT GUSTS REPORTED OVER THE PAST FEW HOURS.
PVS DSCN:
HIGH PRESSURE IS SITUATED WELL OFFSHORE THIS AFTN...WITH
LOW PRESSURE WELL TO THE W OVER THE MID-MISSISSIPPI VALLEY. THE HIGH
WILL CONTINUE TO SLIDE FARTHER OFFSHORE TONIGHT AS LOW PRESSURE
LIFTS NE OVER THE GREAT LAKES. A SW WIND SHOULD AVERAGE 10-15KT
THROUGH THIS EVENING...AND THEN INCREASE TO 15KT BAY/15-20KT OCEAN
LATER THIS EVENING THROUGH FRIDAY MORNING...BEFORE DIMINISHING
FRIDAY AFTN/EVENING AS THE PRESSURE GRADIENT SLACKENS AS A WEAK COLD
FRONT GRADUALLY DROPS INTO THE REGION. THE COLD FRONT PUSHES THROUGH
THE AREA EARLY SATURDAY MORNING...WITH A SUBSEQUENT NORTHERLY SURGE
MIDDAY SATURDAY...WITH A SECONDARY SURGE SATURDAY EVENING. MARGINAL
SCA CONDITIONS ARE POSSIBLE OVER THE BAY (15-20KT N WIND). HIGH
PRESSURE BUILDS OVER THE AREA SATURDAY NIGHT AND SUNDAY...SLIDES
OFFSHORE MONDAY...AND SETTLES OFF THE SOUTHEAST COAST TUESDAY. SEAS
GENERALLY AVERAGE 2-4FT...WITH 2-3FT WAVES IN THE BAY.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT EARLY THIS MORNING FOR
ANZ630>632-634.
&&
$$
SYNOPSIS...SAM/TMG
NEAR TERM...MAS/SAM
SHORT TERM...SAM
LONG TERM...AJZ
AVIATION...MPR
MARINE...AJZ/MPR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
715 PM EDT SAT APR 23 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 424 PM EDT SAT APR 23 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW SPLIT FLOW OVER NAMERICA.
IN THE NRN STREAM...A TROF EXTENDS THRU HUDSON BAY INTO SE CANADA
BTWN RIDGING OVER WRN CANADA AND A CLOSED MID LEVEL HIGH CENTERED
JUST SE OF GREENLAND. IN THE SRN STREAM...A TROF IS OVER THE WRN
CONUS WITH RIDGING OUT OVER THE PLAINS. JET STREAK DEVELOPING IN THE
CONFLUENCE BTWN THE SRN STREAM RIDGE AND NRN STREAM TROF OVER SE
CANADA WILL BE ONE OF THE MAIN PLAYERS IN THE WET WEATHER SETTING UP
ACROSS UPPER MI FOR THE NEXT 36-48HRS. WELL OUT AHEAD OF THE WRN
CONUS TROF...WAA/ISENTROPIC ASCENT REGIME SRPEADING OVER THE NRN
PLAINS HAS LED TO SCT -SHRA DEVELOPMENT FROM ND ACROSS NE MN
THIS AFTN. MID CLOUDS ARE PEELING SE FROM THAT AREA ACROSS UPPER MI.
ALTHOUGH CLOUDS HAVE WORKED TO SOMEWHAT LIMIT THE NORMAL DIURNAL
BUILDING OF MIXING HEIGHTS...SFC DWPTS HAVE STILL FALLEN DOWN INTO
THE SINGLE DIGITS/LOW TEENS ACROSS PORTIONS OF INTERIOR W AND CNTRL
UPPER MI.
A GOOD PATTERN FOR SOAKING RAINS WILL BE SETTING UP ACROSS THE AREA
OVER THE NEXT 36-48HRS AS FCST AREA WILL RESIDE IN A SHARP
BAROCLINIC ZONE RESULTING FROM COLD AIR SPREADING ACROSS SE CANADA
UNDER NRN STREAM TROF AND WARM AIR PUSHING TOWARD THE UPPER
MISSISSIPPI VALLEY AHEAD OF THE SRN STREAM WRN CONUS TROF. IN
FACT...MOST OF THE FCST AREA WILL SEE MDT TO HVY RAINFALL AMOUNTS BY
THE TIME THIS WET PERIOD WRAPS UP MON NIGHT. AFOREMENTIONED JET
STREAK WILL BE A KEY MECHANISM FOR PCPN GENERATION AS THE RIGHT
ENTRANCE WILL PROVIDE LARGER SCALE UPPER DIVERGENCE OVER THE AREA.
AT THE LOWER LEVELS...850MB FRONT SETTING UP IN THE VCNTY OF THE
MI/WI BORDER WILL PROVIDE A FOCUS FOR PCPN DEVELOPMENT UNDER
PERSISTENT FGEN/ISENTROPIC ASCENT. PRECIPITABLE WATER INCREASING TO
AROUND 1 INCH (200-250PCT OF NORMAL) WILL THEN SUPPORT THE EXPECTED
MDT/HVY PCPN AMOUNTS. UTILIZED A MIX OF ALL AVBL MODELS TO CONSTRUCT
POPS/PCPN AMOUNTS FOR TONIGHT/SUN AS MOST OF THE GUIDANCE IS FAIRLY
WELL CLUSTERED ON QPF AND TIMING ONSET OF RAIN. PCPN DEVELOPMENT
TONIGHT MAY BE DELAYED MORE SO THAN REFLECTED IN FCST DUE TO THE
VERY DRY AIR OVER THE AREA ATTM. BY 00Z MON...EXPECT PCPN AMOUNTS
RANGING FROM AROUND ONE-THIRD OF AN INCH OVER THE NRN KEWEENAW
PENINSULA AND NE LUCE COUNTY TO 0.90-1.25 INCHES OVER MUCH OF THE W
AND CNTRL FCST AREA. AS FOR TEMPS...LOWS TONIGHT SHOULD RANGE FROM
THE MID 30S TO LWR 40S...WARMEST FAR W. WITH EXPECTATION OF RAIN
PREVAILING FOR MUCH OF THE DAY IN MOST AREAS...LOWERED MAX TEMPS
SOME FOR SUN. HIGHS SHOULD RANGE FROM THE UPPER 30S NW AND NCNTRL TO
MAINLY THE LWR 40S ELSEWHERE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 511 PM EDT SAT APR 23 2016
COOL CONDITIONS ARE EXPECTED THROUGH THE UPCOMING WEEK...WITH HEAVY
RAIN EXPECTED THROUGH MONDAY.
SUNDAY NIGHT AND MONDAY NIGHT...A STOUT BAROCLINIC ZONE STRETCHING
FROM THE NORTHERN PLAINS TO THE LOWER GREAT LAKES WILL BE THE FOCUS
FOR AN ONGOING ACTIVE PERIOD OF WEATHER. SUBSTANTIAL LOW TO MID-
LEVEL FGEN...WAA...AND LOW-LEVEL MOISTURE TRANSPORT WILL BRING A
CONTINUOUS FEED OF PRECIP ACROSS THE CWA THROUGH AT LEAST MONDAY
MORNING. PWATS APPROACHING 1.5 INCHES ACROSS MN TRACKING TOWARD THE
AREA IN CONJUNCTION WITH AN APPROACHING RIGHT ENTRANCE TO AN UPPER
JET WILL SUPPORT A PERIOD OF MODERATE TO HEAVY RAIN ACROSS ALL BUT
THE KEWEENAW PENINSULA SUNDAY EVENING INTO THE OVERNIGHT HOURS.
MODEL QPF SUNDAY NIGHT ADVERTISES A STRIPE OF 1 TO 2 INCHES WITH
ISOLATED 3 INCH TOTALS ACROSS THE CWA. CURRENT THINKING PUTS THE
HEAVIEST RAIN ALONG A LINE FROM FAR NW WI TO NORTHERN LAKE
MI...INCLUDING IWD...IMT...AND ESC. HOWEVER...MODEL GUIDANCE
CONTINUES TO TREND NORTHWARD WITH THIS SET-UP. IN FACT...LAST
WEEK...LONG TERM GUIDANCE PLACED ALL OF UPPER MI ON THE COLD AND DRY
SIDE OF THE BAROCLINIC ZONE. GIVEN THE MODEL TRENDS...HAVE CONTINUED
THE NORTHWARD PROGRESSION OF THE HIGHEST QPF SUNDAY NIGHT.
AS THE LOW-LEVEL SYSTEM PASSES TO THE SOUTH ON MONDAY...MID-LEVEL
FGEN WILL BE ENHANCED ACROSS THE CWA. THIS WILL FAVOR CONTINUED
MODERATE RAINFALL THROUGH THE MORNING AND POSSIBLY INTO THE
AFTERNOON ACROSS THE SOUTH HALF OF THE CWA. WEAKER FORCING AND DRIER
AIR FILTERING ACROSS THE AREA MONDAY AFTERNOON INTO MONDAY NIGHT
WILL ALLOW FOR A GRADUAL DIMINISHING TREND IN PRECIP AND CLOUD COVER
FROM NORTH TO SOUTH.
WITH THE NORTHWARD TREND IN MODEL GUIDANCE...THE PROSPECTS OF
APPRECIABLE ACCUMULATING SNOW CONTINUE TO DIMINISH. FORECAST
SOUNDINGS INDICATE SLIGHTLY ABOVE FREEZING TEMPS ACROSS THE CWA
THROUGH SUNDAY NIGHT. AS DRYING AND SOME COLDER AIR WORK IN FROM THE
NORTH ON MONDAY...PRECIP MAY SWITCH OVER TO SNOW ACROSS THE HIGH
TERRAIN OF THE NORTH. HOWEVER...WITH A BULK OF THE PRECIP OVER...AND
WITH LATE APRIL DAYTIME HEATING PRESENT...DO NOT EXPECT ANYTHING
MORE THAN UP TO A SLUSHY INCH OF ACCUMULATION ON GRASSY SURFACES
DURING THE DAY.
FORECAST STORM TOTAL QPF TONIGHT THROUGH MONDAY PLACES A SWATH OF 2
TO 3 INCHES SOUTH OF A LINE FROM ONTONAGON TO MARQUETTE TO ST
IGNACE. AMOUNTS QUICKLY DROP OFF TO THE NORTH...WITH LESS THAN A
HALF INCH EXPECTED FOR COPPER HARBOR. GIVEN THE WIDE VARIETY OF QPF
PLACEMENT AMONG MODELS AND ENSEMBLES...IT MUST BE NOTED THAT
LOCALIZED AMOUNTS IN EXCESS OF 4 INCHES WILL BE POSSIBLE THROUGH THE
AFOREMENTIONED PERIOD. GIVEN THE RECENT DRY PERIOD...FLOODING
CONCERNS ARE SOMEWHAT EASED. HOWEVER...WITH LITTLE TO NO
GREENUP...SOILS WILL BECOME SATURATED QUICKLY. HAVE DECIDED TO ISSUE
AN SPS TO ACCOUNT FOR POTENTIALLY VERY HEAVY RAIN AND ELEVATED RIVER
LEVELS THROUGH THE UPCOMING WEEK.
FOR THE REMAINDER OF THE WEEK...COOL AND MOSTLY DRY CONDITIONS WILL
PREVAIL AS HIGH PRESSURE RIDGING EDGES FROM NORTHERN ONTARIO INTO
THE UPPER GREAT LAKES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 714 PM EDT SAT APR 23 2016
VFR CONDITIONS WILL HOLD ON THRU THE EVENING AT ALL SITES UNDER MID
LEVEL CLOUDS. LIGHT RAIN WILL ARRIVE OVERNIGHT AND WILL CONTINUE
THROUGH THE REST OF THE FORECAST PERIOD. ONCE THE RAIN
ARRIVES...CIGS WILL STEADILY LOWER...REACHING IFR AT ALL TERMINALS
AFTER 12Z. CONDITIONS SHOULD CONTINUE TO DETERIORATE FURTHER TO
LIFR/VLIFR DURING THE MORNING HRS AND WILL CONTINUE THAT WAY THE
REST OF THE FORECAST PERIOD AT ALL SITES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 PM EDT SAT APR 23 2016
A CLASSIC SET UP FOR BRISK E TO NE WINDS IS SHAPING UP FOR LAKE
SUPERIOR OVER THE NEXT COUPLE OF DAYS AS HIGH PRES BUILDS INTO
NORTHERN ONTARIO AND A WEAK LOW PRES WAVE TRACKS ALONG A FRONT S OF
UPPER MI. WINDS INITIALLY UNDER 20KT THIS EVENING WILL SLOWLY RAMP
UP TONIGHT...MAINLY OVER WESTERN LAKE SUPERIOR. WINDS THEN INCREASE
MORE NOTABLY ACROSS THE LAKE SUN THRU MON MORNING...REACHING GALES
OVER FAR WESTERN LAKE SUPERIOR LATE SUN MORNING THRU MON AFTN AS
COASTAL CONVERGENCE/FUNNELING ENHANCE THE WINDS IN THAT AREA. A GALE
WARNING HAS BEEN POSTED FOR THAT PART OF THE LAKE. ACROSS THE REST
OF LAKE SUPERIOR...WINDS WILL INCREASE TO 20-30KT. WINDS WILL SLOWLY
DIMINISH MON NIGHT/TUE MORNING...BUT MORE SO TUE AFTN/NIGHT AS THE
NORTHERN ONTARIO HIGH PRES BUILDS INTO THE UPPER LAKES. E TO NE
WINDS GENERALLY UNDER 20KT WILL PREVAIL WED/THU. GIVEN THE E TO NE
WIND DIRECTION...WINDS WILL BE STRONGEST OVER WRN LAKE SUPERIOR ON
BOTH OF THOSE DAYS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 11 AM EDT /10 AM CDT/ SUNDAY TO 8 PM EDT /7 PM
CDT/ MONDAY FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KLUBER
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
434 PM EDT FRI APR 22 2016
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 309 PM EDT FRI APR 22 2016
WV IMAGERY AND RAP ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW INTO
THE NRN LAKES ON THE PERIPHERY OF A DEEP LOW INTO NRN HUDSON BAY.
LOW LEVEL CAA WITH NRLY WINDS KEPT LOW CLOUDS ACROSS MUCH OF THE
FCST AREA INTO EARLY AFTERNOON...BUT NOW BUILDING HIGH PRES FM NW OF
LAKE SUPERIOR HAS ALLOWED FOR INFLUX OF DRIER AIR AND ERODING CLOUD
COVER MID-LATE THIS AFTERNOON. MAX TEMPS TODAY HAVE RANGED FM THE
MID TO UPPER 30S ALONG LAKE SUPERIOR TO AROUND 50F CLOSER TO THE WI
BORDER.
TONIGHT...ALTHOUGH WINDS WILL DIMINISH WITH THE SFC HIGH PRES RIDGE
SLIDING OVER THE AREA...WAA MID CLOUDS FROM SRN MANITOBA AND NRN MN
ARE EXPECTED TO SPREAD IN FM THE W OVERNIGHT DUE TO INCREASING 295-
300K ISENTROPIC ASCENT WHICH SHOULD KEEP TEMPS FROM DROPPING OFF TOO
FAR. TEMPS MAY STILL FALL INTO THE MID 20S CENTRAL AND EAST BEFORE
THE CLOUDS MOVE IN. OTHERWISE...EXPECT MIN READINGS IN THE LOWER 30S
WEST.
SAT...A WNW FLOW ALOFT WILL DOMINATE THE UPPER GREAT LAKES BETWEEN
AN UPR RIDGE AXIS IN THE PLAINS AND AN UPR TROUGH OVER ERN CANADA.
MODELS SHOW MID/HIGH CLDS CONTINUING TO SPREAD INTO UPPER MI WITH
WAA TO THE NE OF SHARPENING FNT FM THE DAKOTAS INTO MN.
HOWEVER...THE MAJORITY OF MODELS INDICATE LINGERING LLVL DRY AIR
ASSOCIATED WITH SLOWLY DEPARTING SFC HIGH PRES WL KEEP THE CWA DRY.
ONLY THE 12Z GFS SHOWS RAIN REACHING INTO THE NW CWA WHERE MODELS
INDICATE PROXIMITY TO STRONGER H7 FGEN ALONG AND NE OF SHARPENING
FRONTAL BOUNDARY.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 434 PM EDT FRI APR 22 2016
BUILDING HEIGHTS OVER GREENLAND (500MB HEIGHTS UP TO 2.5 STANDARD
DEVIATIONS ABOVE CLIMATOLOGY) THRU EARLY NEXT WEEK WILL SUPPORT
TROFFING OVER SE CANADA AND FAIRLY COLD AIR FOR LATE APR ACROSS
ONTARIO AND QUEBEC. AS A RESULT...A RATHER SHARP BAROCLINIC ZONE
WILL SET UP ACROSS THE UPPER LAKES BTWN THE LATE SEASON COLD AIR
EXPANDING ACROSS SE CANADA AND WARM AIR SPREADING ACROSS THE PLAINS
AHEAD OF A SRN STREAM SHORTWAVE LIFTING OUT OF A MEAN TROF OVER THE
CNTRL/SRN ROCKIES. THIS BAROCLINIC ZONE WILL SET THE STAGE FOR
ACTIVE WEATHER AND POTENTIAL OF MDT TO EVEN HVY PCPN AMOUNTS IN THE
SUN/MON TIME FRAME. GIVEN THE PROXIMITY OF THE COLD AIR...IT`S NOT
OUT OF THE QUESTION THAT ACCUMULATING WET SNOW COULD ALSO OCCUR IN
SOME AREAS OF UPPER MI. LATER NEXT WEEK...THE HEIGHT ANOMALIES WILL
WEAKEN...BUT THE TROF WILL REMAIN IN SE CANADA...RESULTING IN A
CONTINUED BLO NORMAL TEMP REGIME LIKELY PERSISTING FOR UPPER MI THRU
THE ENTIRE WEEK. AFTER THE SUN/MON PCPN...ANOTHER OPPORTUNITY OF
PCPN MAY OCCUR WED/THU IF THE NEXT SHORTWAVE LIFTING OUT OF THE MEAN
ROCKIES TROF MOVES FAR ENOUGH NE TO AFFECT THE UPPER LAKES. DRY
WEATHER SHOULD THEN ROUND OUT THE WEEK. LOOKING FARTHER AHEAD...
NAEFS OUTLOOKS IN THE 8-14DAY PERIOD (APR30-MAY7) INDICATE TEMPS
OVERALL CLOSE TO NORMAL FOR UPPER MI.
BEGINNING SAT NIGHT...-RA WILL DEVELOP/SPREAD INTO THE FCST AREA
WITHIN SHARPENING BAROCLINIC ZONE...LOW-MID LEVEL FGEN...UPPER
DIVERGENCE IN RRQ OF 120KT UPPER JET ACROSS NRN ONTARIO/SRN QUEBEC
AND STRENGTHENING ISENTROPIC ASCENT. WILL CARRY HIGHER CATEGORICAL
POPS INTO ROUGHLY THE FAR HALF IN THE 06Z-12Z PERIOD.
SUN/MON...PCPN GENERATION IN THE BAROCLINIC ZONE WILL CONTINUE TO BE
MAINTAINED BY LOW-MID LEVEL FGEN AND THE RIGHT ENTRANCE OF UPPER JET
ACROSS NRN ONTARIO/SRN QUEBEC. IN ADDITION...SHORTWAVE ENERGY
EJECTING FROM THE CNTRL/SRN ROCKIES INTO THE UPPER MISSISSIPPI
VALLEY...THOUGH WEAKENING...WILL FURTHER AID THE PCPN. WITH
PRECIPITABLE WATER OF 0.75 TO A LITTLE OVER 1 INCH...ROUGHLY 200-
250PCT OF NORMAL...POTENTIAL WILL BE THERE FOR MDT TO EVEN LOCALLY
HVY PCPN AMOUNTS. THIS FCST WILL SHOW TOTAL QPF SAT NIGHT TO MON
EVENING RANGING FROM AROUND ONE-THIRD OF AN INCH OVER THE NRN
KEWEENAW PENINSULA TO AROUND 2 INCHES ALONG THE WI/MI BORDER INTO
SCNTRL UPPER MI. MODELS HAVE NOT BE VERY CONSISTENT ON THERMAL
FIELDS AND POTENTIAL FOR ACCUMULATING SNOW. ABOUT ALL THAT CAN BE
SAID AT THIS POINT IS THAT THERE IS SOME POTENTIAL FOR ACCUMULATING
WET/HVY SNOW OVER PARTS OF UPPER MI...MAINLY THE HIGHER TERRAIN OF
THE W HALF LATE SUN NIGHT/MON MORNING.
PCPN SHOULD DIMINISH/END W TO E MON NIGHT AS WEAKENING SHORTWAVE
ENERGY LIFTING INTO THE UPPER MISSISSIPPI VALLEY MON SHIFTS E ACROSS
THE GREAT LAKES REGION. WILL IGNORE THE CANADIAN MODEL WHICH IS AN
OUTLIER IN BEING MUCH SLOWER TO SHIFT THE SHORTWAVE E...RESULTING IN
PCPN (RAIN/SNOW) LINGERING INTO TUE AFTN.
SKIES WILL CLEAR OUT FOR TUE. IN FACT...WITH GFS FCST SOUNDINGS
SHOWING A DEEP DRY AIR MASS...SHOULD SEE ABUNDANT SUNSHINE. DESPITE
THE SUN...IT WILL BE CHILLY UNDER 850MB TEMPS OF -2 TO -4C AT
MIDDAY. IN ADDITION...CHILL WILL BE AIDED BY A GRADIENT NE WIND TO
START THE DAY AND THEN MESO HIGH DEVELOPING OVER LAKE SUPERIOR IN
THE AFTN MAINTAINING LAKE COOLING.
WED/THU...ATTENTION SHIFTS TO THE NEXT CLUSTER OF SHORTWAVE ENERGY
THAT SETTLED INTO THE MEAN CNTRL/SRN ROCKIES TROF MON/TUE. MUCH WILL
DEPEND ON THE STRENGTH OF THE CONTINUED SE CANADA TROF WHICH WILL BE
EVOLVING INTO A MID LEVEL LOW. IF ITS INFLUENCE REMAINS STRONGER
FARTHER S...THE EJECTING ENERGY WILL BE SUPPRESSED S OF THE AREA...
KEEPING UPPER MI UNDER DRY WEATHER...SIMILAR TO RECENT GFS RUNS AND
THE 12Z CANADIAN. IF THE TROF/CLOSED LOW IN SE CANADA IS
WEAKER/FARTHER N...THE EJECTING ENERGY WILL LIFT FARTHER TO THE NE
AND BRING MORE RAIN INTO UPPER MI...SIMILAR TO RECENT ECMWF RUNS.
HOWEVER...THE 12Z ECMWF HAS STARTED TO BACK AWAY FROM ITS MORE
AGGRESSIVE NE PUSH OF PCPN. FOR NOW...FCST WILL UTILIZE A CONSENSUS
APPROACH WHICH RESULTS IN MOSTLY SCHC POPS WED/THU.
DRY WEATHER WILL THEN ROUND OUT THE WEEK AS HIGH PRES BUILDS SE INTO
THE GREAT LAKES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 109 PM EDT FRI APR 22 2016
MVFR CLOUD DECK AT KSAW WILL ERODE SHORTLY AFT 18Z AS DRIER AIR WORKS
IN FROM NORTH OF THE LAKE. HIGH PRES BUILDING INTO THE REGION WILL
MAINTAIN VFR CONDITIONS FOR ALL TAF SITES THROUGH THE REST OF THE
FCST PERIOD. THERE WILL BE SOME INCREASE IN MID-HIGH CLOUDS INTO
KCMX AND KSAW LATE SAT MORNING AS WARM AIR PUSHES NORTH OF A FRONTAL
BOUNDARY OVER THE NORTHERN PLAINS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 309 PM EDT FRI APR 22 2016
HIGH PRES WILL MOVE ACROSS LAKE SUPERIOR TONIGHT WITH WINDS
DIMINISHING TO 15 KNOTS OE LESS INTO SAT. AS THE HIGH EXITS TO THE
EASTERN SEABOARD AND LOW PRESSURE DEVELOPS OVER THE PLAINS ON
SUNDAY, NORTHEAST WINDS WILL INCREASE TO 20-30 KTS SUNDAY INTO
MONDAY. THE STRONGEST WINDS WILL BE OVER WESTERN LAKE SUPERIOR WHERE
WINDS MAY APPROACH GALES AT TIMES. WINDS DIMINISH TO LESS THAN 20
KTS MONDAY NIGHT INTO WEDNESDAY AS HIGH PRESSURE MOVES BACK ACROSS
THE REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...ROLFSON
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
404 PM EDT FRI APR 22 2016
.DISCUSSION...
DESPITE A TRUE SPLIT FLOW CONFIGURATION OVER THE HEMISPHERE...THE
WEATHER FOR SOUTHEASTERN MICHIGAN WILL CONTINUE TO BE INFLUENCED IN
THE NEAR TERM (NEXT 6-8 HRS) BY A DAMPENING UPPER LEVEL TROUGH. THIS
TROUGH FEATURE IS THE OLD TEXAS UPPER LEVEL PV ANOMALY BECOMING
REACCLIMATED TO THE CONSOLIDATED POLAR WESTERLY BELT. ALL OF
THIS...WITH A PARTIAL CONNECTION BETWEEN PV RESERVOIR HAS BEEN SLOW
TO OCCUR. THUS...THE SLUGGISH SOUTHWARD PROGRESSION TO THE
FRONT/DEWPOINT GRADIENT SEEN OVER MONROE COUNTY TODAY. HIGHER THAN
EXPECTED DEWPOINTS IN THE MID 50S HAS RESULTED IN SBCAPES OF AROUND
500 J/KG. LATEST HIRES EXPLICIT CAM OUTPUT SUPPORTS A CONTINUED
POTENTIAL FOR SOME SHOWERS THROUGH 21Z BEFORE ENDING. RAP BASED SPC
MESOANALYSIS SHOWS THAT THE POCKET OF INSTABILITY HAS ESSENTIALLY
BEEN PUSHED SOUTH OF THE CWA BORDER ALREADY...AND LATEST RADAR
TRENDS SUPPORT THIS IDEA.
MAIN FORECAST ITEM FOR TONIGHT CENTERS ON HOW FAST CLOUDS WILL CLEAR
OUT. VISIBLE IMAGERY SUGGESTS A STRONG DEPENDENCE/FOOTING WITHIN
THE BOUNDARY LAYER. GIVEN DRY AIR ADVECTION IN THE MODELS...AND THIS
DEPENDENCE ON BOUNDARY LAYER CLOUD...THE IDEA IS THAT CLOUDS WILL
CLEAR OUT RAPIDLY THIS EVENING. THE CLEAR SKIES...LIGHT WINDS WITH
BUILDING SURFACE HIGH PRESSURE SUGGESTS COLD TEMPERATURES TONIGHT.
WENT VERY AGGRESSIVE AND WORKED IN THE COLDEST OF THE GUIDANCE
WITH LOWS SATURDAY MORNING OF LOWER TO MIDDLE 30S.
STABLE SURFACE HIGH PRESSURE AND CLEAR SKIES SATURDAY WILL PROVIDE
EFOR WONDERFUL WEATHER TO SOUTHEASTERN MICHIGAN. FORECASTED MIXING
HEIGHTS ARE NOT PARTICULARLY LOW...BUT UPSTREAM AIRMASS NORTH OF
LAKE HURON IS VERY DRY AND STABLE...(DEWPOINTS IN THE 20S AND
TEENS). PATTERN RECOGNITION AND TIME OF YEAR SUGGESTS
OVERACHIEVEMENT POTENTIAL FROM THE INSOLATION...BUT REALLY WENT
COOLER FOR SATURDAY. THE OUTGOING FORECAST WILL READ MIDDLE TO UPPER
50S MANY AREAS...LOWER TO MIDDLE 40S ALONG THE SHORELINE. NO REAL
WIND TO SPEAK OF...BUT THE DRY AIRMASS/EVAPORATIVE COOLING POTENTIAL
WILL MAKE THINGS COOLER THAN THEY WOULD OTHERWISE SEEM.
SUNDAY...THE MAIN QUESTION IS EXACTLY WHERE A STRETCHING DEFORMATION
AXIS OR THE NARROW THINNING WEAKNESS IN THE GEOPOTENTIAL HEIGHT
FIELD WILL RESIDE. FORECAST TRENDS THE PAST 24 HOURS HAS BEEN
POINTING TO NORTH OF THE CWA. CONFIDENCE AT THIS TIME IS REASONABLY
THAT IT WILL BE NORTH ENOUGH TO KEEP PRECIPITATION CHANCES OUT OF
AREAS SOUTH OF M46. FOR THE TRI CITIES...THE POTENTIAL FOR SOME RAIN
WILL INCREASE BY THE LATE AFTERNOON...BUT CANNOT GO MORE THAN A
CHANCE POP. LATEST FORECAST DATA SUGGESTS THE SATURATION TRAPPED
WITHIN THIS DEFORMATION ZONE WILL UNDERGO A SIGNIFICANT ONSLAUGHT OF
DRY AIR ADVECTION FROM BOTH THE NORTH AND SOUTH ON SUNDAY. IN
FACT...SOME PROGS SUGGEST THAT A SIGNIFICANT CENTROID OF THE UPPER
LEVEL RIDGE WILL ROLL THROUGH SOUTHEASTERN MICHIGAN EARLY SUNDAY.
DUE TO THE SPLIT FLOW...THIS AIRMASS WILL NOT BE A PARTICULARLY
WARM/HOT ONE...BUT WONDERFUL WEATHER IS NOW EXPECTED FOR A GOOD
PORTION OF THE CWA WITH TEMPERATURES REACHING THE UPPER 60S TO LOW
70S.
SURFACE LOW PRESSURE WILL TRACK ACROSS LOWER MICHIGAN ON
MONDAY...ALLOWING RAIN SHOWERS TO PERSIST MUCH OF THE DAY AND INTO
MONDAY NIGHT. THE LOW WILL SLOWLY TRACK EASTWARD ON TUESDAY MORNING
AS HIGH PRESSURE BUILDS INTO THE REGION OUT OF CANADA. THIS HIGH
WILL ALLOW DRY CONDITIONS AND COOLER AIR TO FILTER INTO SOUTHEAST
MICHIGAN RESULTING IN HIGH TEMPS ON TUESDAY TO ONLY BE IN THE UPPER
50S. THIS HIGH WILL LAST THROUGH WEDNESDAY EVENING. THE NEXT MAJOR
SYSTEM ARRIVES WEDNESDAY NIGHT AND INTO THURSDAY AS A WARM FRONT
PUSHES NORTHWARD INTO SOUTHEAST MICHIGAN. THE CENTER OF THE LOW
PRESSURE SYSTEM WILL THEN TRACK OVER LOWER MICHIGAN ON THURSDAY AND
THURSDAY EVENING KEEPING CONDITIONS ACROSS SOUTHEAST MICHIGAN WET
AND CLOUDY.
&&
.MARINE...
NORTHERLY FLOW OVER LAKE HURON BETWEEN 15 TO 20 KNOTS THIS AFTERNOON
WILL GRADUALLY EASE JUST A BIT TO AROUND 15 KNOTS TONIGHT...AND
BECOMING NORTHEAST IN PROCESS. THIS WILL ALLOW WAVES TO DIMINISH
FROM THE 3 TO 6 FOOT RANGE TO MORE LIKE 2 TO 4 FEET OVER THE
SOUTHERN LAKE HURON BASIN. HIGH PRESSURE BUILDING INTO THE CENTRAL
GREAT LAKES TOMORROW WILL LEAD TO FAVORABLE BOATING
CONDITIONS...WITH LIGHT WINDS AND LOW WAVES...ALONG WITH FULL
SUNSHINE. A DEVELOPING FRONTAL BOUNDARY FOR THE SECOND HALF OF THE
WEEKEND WILL LEAD TO STRENGTHENING EASTERLY WINDS IN EXCESS OF 20
KNOTS OVER NORTHERN LAKE HURON...ALONG WITH SHOWERS...WHICH WILL
SPREAD ACROSS THE ENTIRE MARINE WATERS AS WE HEAD INTO MONDAY.
&&
.HYDROLOGY...
A STRENGTHENING FRONTAL BOUNDARY ON SUNDAY WILL BRING THE NEXT
CHANCE OF SHOWERS TO THE AREA...BUT BULK OF THE RAINFALL IS EXPECTED
TO OCCUR OVER NORTHERN LOWER MICHIGAN. A LOW RIDING ALONG THE FRONT
ON MONDAY WILL ALLOW FOR SHOWERS TO SPREAD ACROSS ALL OF SOUTHEAST
MICHIGAN...WITH THE POTENTIAL FOR RAINFALL TOTALS IN EXCESS OF HALF
AN INCH.
&&
.AVIATION...ISSUED 1256 PM EDT FRI APR 22 2016
LOW LEVEL MOISTURE GRADUALLY SCOURING OUT...WITH MVFR CEILINGS
LIKELY DISSIPATING LATE THIS EVENING...ALTHOUGH EXACT TIMING IS
UNCERTAIN...AS COLD NORTH/NORTHEAST FLOW OFF LAKE HURON COMPLICATES
THE FORECAST A BIT. HIGHER CONFIDENCE SKIES WILL BECOME CLEAR/MOSTLY
CLEAR AFTER MIDNIGHT...CONTINUING INTO THE DAY ON SATURDAY AS
SURFACE HIGH PRESSURE TAKES HOLD OF THE CENTRAL GREAT LAKES.
FOR DTW...SHOWERS TOWARD THE SOUTHERN MICHIGAN BORDER EARLY THIS
AFTERNOON EXPECTED TO REMAIN SOUTH OF THE TERMINAL.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CEILINGS 5 KFT OR LESS THROUGH THE AFTERNOON...MEDIUM
THIS EVENING...THEN LOW OVERNIGHT.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR LHZ421-
441>443.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
DISCUSSION...CB
MARINE.......SF
HYDROLOGY....SF
AVIATION.....SF
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
311 PM EDT FRI APR 22 2016
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 309 PM EDT FRI APR 22 2016
WV IMAGERY AND RAP ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW INTO
THE NRN LAKES ON THE PERIPHERY OF A DEEP LOW INTO NRN HUDSON BAY.
LOW LEVEL CAA WITH NRLY WINDS KEPT LOW CLOUDS ACROSS MUCH OF THE
FCST AREA INTO EARLY AFTERNOON...BUT NOW BUILDING HIGH PRES FM NW OF
LAKE SUPERIOR HAS ALLOWED FOR INFLUX OF DRIER AIR AND ERODING CLOUD
COVER MID-LATE THIS AFTERNOON. MAX TEMPS TODAY HAVE RANGED FM THE
MID TO UPPER 30S ALONG LAKE SUPERIOR TO AROUND 50F CLOSER TO THE WI
BORDER.
TONIGHT...ALTHOUGH WINDS WILL DIMINISH WITH THE SFC HIGH PRES RIDGE
SLIDING OVER THE AREA...WAA MID CLOUDS FROM SRN MANITOBA AND NRN MN
ARE EXPECTED TO SPREAD IN FM THE W OVERNIGHT DUE TO INCREASING 295-
300K ISENTROPIC ASCENT WHICH SHOULD KEEP TEMPS FROM DROPPING OFF TOO
FAR. TEMPS MAY STILL FALL INTO THE MID 20S CENTRAL AND EAST BEFORE
THE CLOUDS MOVE IN. OTHERWISE...EXPECT MIN READINGS IN THE LOWER 30S
WEST.
SAT...A WNW FLOW ALOFT WILL DOMINATE THE UPPER GREAT LAKES BETWEEN
AN UPR RIDGE AXIS IN THE PLAINS AND AN UPR TROUGH OVER ERN CANADA.
MODELS SHOW MID/HIGH CLDS CONTINUING TO SPREAD INTO UPPER MI WITH
WAA TO THE NE OF SHARPENING FNT FM THE DAKOTAS INTO MN.
HOWEVER...THE MAJORITY OF MODELS INDICATE LINGERING LLVL DRY AIR
ASSOCIATED WITH SLOWLY DEPARTING SFC HIGH PRES WL KEEP THE CWA DRY.
ONLY THE 12Z GFS SHOWS RAIN REACHING INTO THE NW CWA WHERE MODELS
INDICATE PROXIMITY TO STRONGER H7 FGEN ALONG AND NE OF SHARPENING
FRONTAL BOUNDARY.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 351 AM EDT FRI APR 22 2016
LOOKS LIKE A CHILLY...ACTIVE WX PATTERN WL DOMINATE LATE THIS
WEEKEND INTO EARLY NEXT WEEK AS A VERY TIGHT BAROCLINIC ZN WL SETUP
ACRS THE UPR GREAT LKS UNDER THE CONFLUENCE ZN BTWN ARCTIC AIRSTREAM
IN CANADA AND AN ACTIVE POLAR BRANCH FLOW OVER THE NRN CONUS. SOME
MDT TO HEAVY PCPN IS LIKELY TO FALL OVER AT LEAST THE S HALF OF UPR
MI...WHICH WL BE CLOSER TO A STNRY FNT RUNNING W-E THRU THE UPR
MIDWEST. IF ENUF COLD AIR IN THE NNE FLOW BTWN BLDG HI PRES INTO NRN
ONTARIO AND THE LOWER PRES TO THE S ADVECTS INTO THE CWA AND THIS
AIR IS NOT EXCESSIVELY DRY...THERE COULD BE SOME ACCUMULATING WET SN
OVER MAINLY THE HIER TERRAIN OF NRN UPR MI ON SUN NGT INTO MON.
QUIETER BUT STILL RELATIVELY CHILLY WX WL BE THE RULE FOR MID WEEK.
SAT...UPR MI IS FCST TO BE DOMINATED BY WNW FLOW ALF BTWN UPR RDG
AXIS IN THE PLAINS AND UPR TROFFING IN ERN CANADA. ALTHOUGH MODELS
INDICATE A GOOD DEAL OF MID/HI CLDS RELATED TO WAA TO THE NE OF
SHARPENING FNT FM THE DAKOTAS INTO MN WL IMPACT THE CWA...SUSPECT
LINGERING LLVL DRY AIR ASSOCIATED WITH SLOWLY DEPARTING SFC HI PRES
WL KEEP THE CWA DRY. BEST CHC FOR SOME RAIN WL BE OVER THE NW CWA
CLOSER TO BAND OF STRONGER H7 FGEN TO THE NE OF SHARPENING FNT.
SAT NGT...MODELS IN FAIRLY GOOD AGREEMENT SHOWING MORE WIDESPREAD RA
DVLPG OVER THE CWA ESPECIALLY NEAR THE WI BORDER WITH SHARPENING
BAROCLINIC ZN/FGEN/INCRSG UPR DVGC IN RRQ OF 120KT H3 JET CORE
MOVING TO JUST S OF JAMES BAY BY 12Z SUN. WL CARRY THE HIER
CATEGORICAL POPS NEAR THE WI BORDER IN THE 06Z-12Z PERIOD.
SUN THRU MON...UPR MI IS FCST TO BE CLOSE TO SHARP BAROCLINIC ZN
UNDER CONFLUENCE ZN BTWN ARCTIC BRANCH NW FLOW DOMINATING QUEBEC AND
A WSW POLAR BRANCH FLOW OVER THE NRN CONUS. DESPITE THE UNFAVORABLE
LOOK OF THE CONFLUENT UPR FLOW WELL TO THE NE OF SHRTWV RIDING ENEWD
THRU THE NRN PLAINS WHICH WOULD TEND TO FAVOR DRY WX...MOST OF THE
MEDIUM RANGE MODELS GENERATE SOME MDT TO HEAVY PCPN OVER MAINLY THE
S HALF OF THE CWA. UPR DVGC IN RRQ OF 120KT H3 JET MAX JUST S OF
JAMES BAY AS WELL AS SHARP...PERSISTENT H85-7 FGEN N OF THE H85
WARM/STNRY FNT STRETCHING E ACRS WI FM LO IN THE NRN PLAINS AND
UNDER AXIS OF PWAT AOA AN INCH OVER THE SRN CWA LOOK TO BE THE
ENHANCEMENT FACTORS THAT WOULD OVERCOME THE UPR CONFLUENCE THAT WL
WEAKEN DISTURBANCES RIDING ENEWD TOWARD THE CWA AHEAD OF THE MAIN
SHRTWV TO THE SW. ALTHOUGH SOME OF THE COLDER MODELS` FCST SDNGS/
THERMAL FIELDS WITH H85 TEMPS AOB 0C INDICATE AT LEAST SOME OF THE
PCPN NEAR THE NRN EDGE OF THE BAND WL BE IN THE FORM OF SN...SHARP
GRADIENT IN SFC-H85 MSTR BTWN THE FNT AND CHILLY HI PRES BLDG INTO
NRN ONTARIO WL LIKELY BRING A RATHER SHARP NRN EDGE TO THE PCPN BAND
AND LIMIT THE COVERAGE OF SGNFT SN. BUT IF THE COLDER GUIDANCE IS
CORRECT AND THE LLVL DRYING IS NOT TOO AGGRESSIVE...NOT OUT OF THE
QUESTION THERE COULD BE SEVERAL INCHES OF WET...HEAVY SN OVER
PORTIONS OF THE NRN CWA MAINLY ON SUN NGT/MON MRNG AS STEADY LLVL NE
WINDS ADVECT COLDER AIR INTO THE LKS TO THE S OF THE ONTARIO HI PRES.
MON NGT THRU THU...AS THE HI PRES OVER NORTHERN ONTARIO BUILDS S
INTO THE UPR LKS UNDER CONFLUENT NW FLOW ALF BTWN UPR RDG AXIS
SHIFTING E FM THE PLAINS AND CLOSED UPR LO OVER QUEBEC...EXPECT
LINGERING PCPN TO END ON MON NGT...WITH THE HI PRES BRINGING DRY
WX/MOCLR SKIES ON TUE INTO WED. DEPENDING ON HOW QUICKLY THE QUEBEC
CLOSED LO WEAKENS AND WHETHER OR NOT THE UPR FLOW INTO THE GREAT LKS
TURNS MORE PROGRESSIVE...ANOTHER LO PRES MOVE ENE FM THE PLAINS
COULD BRING MORE PCPN TO THE AREA NEXT THU. BUT IF THE QUEBEC CLOSED
LO IS MORE RESILIENT...THAT NEXT PLAINS LO COULD BE SHUNTED TO THE
SW. EXPECT RELATIVELY CHILLY WX THRU THE EXTENDED PERIOD WITH SUB
ZERO H85 TEMPS DOMINATING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 109 PM EDT FRI APR 22 2016
MVFR CLOUD DECK AT KSAW WILL ERODE SHORTLY AFT 18Z AS DRIER AIR WORKS
IN FROM NORTH OF THE LAKE. HIGH PRES BUILDING INTO THE REGION WILL
MAINTAIN VFR CONDITIONS FOR ALL TAF SITES THROUGH THE REST OF THE
FCST PERIOD. THERE WILL BE SOME INCREASE IN MID-HIGH CLOUDS INTO
KCMX AND KSAW LATE SAT MORNING AS WARM AIR PUSHES NORTH OF A FRONTAL
BOUNDARY OVER THE NORTHERN PLAINS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 309 PM EDT FRI APR 22 2016
HIGH PRES WILL MOVE ACROSS LAKE SUPERIOR TONIGHT WITH WINDS
DIMINISHING TO 15 KNOTS OE LESS INTO SAT. AS THE HIGH EXITS TO THE
EASTERN SEABOARD AND LOW PRESSURE DEVELOPS OVER THE PLAINS ON
SUNDAY, NORTHEAST WINDS WILL INCREASE TO 20-30 KTS SUNDAY INTO
MONDAY. THE STRONGEST WINDS WILL BE OVER WESTERN LAKE SUPERIOR WHERE
WINDS MAY APPROACH GALES AT TIMES. WINDS DIMINISH TO LESS THAN 20
KTS MONDAY NIGHT INTO WEDNESDAY AS HIGH PRESSURE MOVES BACK ACROSS
THE REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...KC
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
113 PM EDT FRI APR 22 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 457 AM EDT FRI APR 22 2016
WV IMAGERY AND RAP ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW INTO
THE NRN LAKES ON THE PERIPHERY OF A DEEP LOW INTO NRN HUDSON BAY.
LOW LEVEL CAA WITH NRLY WINDS INCREASED OVERNIGHT AS THE PRES
GRADIENT TIGHTENED BETWEEN HIGH PRESSURE INTO NRN ONTARIO AND TROUGH
OVER THE LOWER LAKES. CONVERGENT AND UPSLOPE FLOW INTO N CNTRL UPPER
MI COMBINED WITH LINGERING LOW LEVEL MOISTURE SUPPORTED SOME DZ/FZDZ
THAT HAS MIXED WITH LIGHT SNOW.
TODAY...EXPECT THAT THE LIGHT SNOW WILL TRANSITION TO MAINLY DZ/FZDZ
EARLY THIS MORNING AS THE DEEPER MOISTURE DEPARTS...LEAVING THE
MOIST LAYER WARMER THAN -8C. SATELLITE AND MODEL 925-900 MB RH FCST
TRENDS SUGGEST THAT THE LIGHT PCPN SHOULD DIMINISH OR END AROUND
12Z-14Z BUT THAT THE CLOUDS MAY PERSIST...MOVING OUT BTWN 15Z-18Z AS
HIGH PRESSURE WITH LOW LEVEL DRYING BUILDS IN. OTHERWISE...SUNSHINE
WITH 850 MB TEMPS NEAR -2C DURING THE AFTERNOON WILL HELP BOOST
INLAND TEMPS TO AROUND 50. OTHERWISE...NRLY FLOW OFF OF LAKE SUPERIOR
WILL LIMIT HIGH TEMPS CLOSER TO 40.
TONIGHT...ALTHOUGH WINDS WILL DIMINISH WITH THE SFC RIDGE OVER THE
AREA...MID CLOUDS MOVING IN OVERNIGHT WITH 700-500 MB WAA WILL KEEP
TEMPS FROM DROPPING OFF TOO FAR. TEMPS MAY STILL FALL INTO THE MID
20S CENTRAL AND EAST BEFORE THE CLOUDS MOVE IN. OTHERWISE...EXPECT
MIN READINGS IN THE LOWER 30S WEST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 351 AM EDT FRI APR 22 2016
LOOKS LIKE A CHILLY...ACTIVE WX PATTERN WL DOMINATE LATE THIS
WEEKEND INTO EARLY NEXT WEEK AS A VERY TIGHT BAROCLINIC ZN WL SETUP
ACRS THE UPR GREAT LKS UNDER THE CONFLUENCE ZN BTWN ARCTIC AIRSTREAM
IN CANADA AND AN ACTIVE POLAR BRANCH FLOW OVER THE NRN CONUS. SOME
MDT TO HEAVY PCPN IS LIKELY TO FALL OVER AT LEAST THE S HALF OF UPR
MI...WHICH WL BE CLOSER TO A STNRY FNT RUNNING W-E THRU THE UPR
MIDWEST. IF ENUF COLD AIR IN THE NNE FLOW BTWN BLDG HI PRES INTO NRN
ONTARIO AND THE LOWER PRES TO THE S ADVECTS INTO THE CWA AND THIS
AIR IS NOT EXCESSIVELY DRY...THERE COULD BE SOME ACCUMULATING WET SN
OVER MAINLY THE HIER TERRAIN OF NRN UPR MI ON SUN NGT INTO MON.
QUIETER BUT STILL RELATIVELY CHILLY WX WL BE THE RULE FOR MID WEEK.
SAT...UPR MI IS FCST TO BE DOMINATED BY WNW FLOW ALF BTWN UPR RDG
AXIS IN THE PLAINS AND UPR TROFFING IN ERN CANADA. ALTHOUGH MODELS
INDICATE A GOOD DEAL OF MID/HI CLDS RELATED TO WAA TO THE NE OF
SHARPENING FNT FM THE DAKOTAS INTO MN WL IMPACT THE CWA...SUSPECT
LINGERING LLVL DRY AIR ASSOCIATED WITH SLOWLY DEPARTING SFC HI PRES
WL KEEP THE CWA DRY. BEST CHC FOR SOME RAIN WL BE OVER THE NW CWA
CLOSER TO BAND OF STRONGER H7 FGEN TO THE NE OF SHARPENING FNT.
SAT NGT...MODELS IN FAIRLY GOOD AGREEMENT SHOWING MORE WIDESPREAD RA
DVLPG OVER THE CWA ESPECIALLY NEAR THE WI BORDER WITH SHARPENING
BAROCLINIC ZN/FGEN/INCRSG UPR DVGC IN RRQ OF 120KT H3 JET CORE
MOVING TO JUST S OF JAMES BAY BY 12Z SUN. WL CARRY THE HIER
CATEGORICAL POPS NEAR THE WI BORDER IN THE 06Z-12Z PERIOD.
SUN THRU MON...UPR MI IS FCST TO BE CLOSE TO SHARP BAROCLINIC ZN
UNDER CONFLUENCE ZN BTWN ARCTIC BRANCH NW FLOW DOMINATING QUEBEC AND
A WSW POLAR BRANCH FLOW OVER THE NRN CONUS. DESPITE THE UNFAVORABLE
LOOK OF THE CONFLUENT UPR FLOW WELL TO THE NE OF SHRTWV RIDING ENEWD
THRU THE NRN PLAINS WHICH WOULD TEND TO FAVOR DRY WX...MOST OF THE
MEDIUM RANGE MODELS GENERATE SOME MDT TO HEAVY PCPN OVER MAINLY THE
S HALF OF THE CWA. UPR DVGC IN RRQ OF 120KT H3 JET MAX JUST S OF
JAMES BAY AS WELL AS SHARP...PERSISTENT H85-7 FGEN N OF THE H85
WARM/STNRY FNT STRETCHING E ACRS WI FM LO IN THE NRN PLAINS AND
UNDER AXIS OF PWAT AOA AN INCH OVER THE SRN CWA LOOK TO BE THE
ENHANCEMENT FACTORS THAT WOULD OVERCOME THE UPR CONFLUENCE THAT WL
WEAKEN DISTURBANCES RIDING ENEWD TOWARD THE CWA AHEAD OF THE MAIN
SHRTWV TO THE SW. ALTHOUGH SOME OF THE COLDER MODELS` FCST SDNGS/
THERMAL FIELDS WITH H85 TEMPS AOB 0C INDICATE AT LEAST SOME OF THE
PCPN NEAR THE NRN EDGE OF THE BAND WL BE IN THE FORM OF SN...SHARP
GRADIENT IN SFC-H85 MSTR BTWN THE FNT AND CHILLY HI PRES BLDG INTO
NRN ONTARIO WL LIKELY BRING A RATHER SHARP NRN EDGE TO THE PCPN BAND
AND LIMIT THE COVERAGE OF SGNFT SN. BUT IF THE COLDER GUIDANCE IS
CORRECT AND THE LLVL DRYING IS NOT TOO AGGRESSIVE...NOT OUT OF THE
QUESTION THERE COULD BE SEVERAL INCHES OF WET...HEAVY SN OVER
PORTIONS OF THE NRN CWA MAINLY ON SUN NGT/MON MRNG AS STEADY LLVL NE
WINDS ADVECT COLDER AIR INTO THE LKS TO THE S OF THE ONTARIO HI PRES.
MON NGT THRU THU...AS THE HI PRES OVER NORTHERN ONTARIO BUILDS S
INTO THE UPR LKS UNDER CONFLUENT NW FLOW ALF BTWN UPR RDG AXIS
SHIFTING E FM THE PLAINS AND CLOSED UPR LO OVER QUEBEC...EXPECT
LINGERING PCPN TO END ON MON NGT...WITH THE HI PRES BRINGING DRY
WX/MOCLR SKIES ON TUE INTO WED. DEPENDING ON HOW QUICKLY THE QUEBEC
CLOSED LO WEAKENS AND WHETHER OR NOT THE UPR FLOW INTO THE GREAT LKS
TURNS MORE PROGRESSIVE...ANOTHER LO PRES MOVE ENE FM THE PLAINS
COULD BRING MORE PCPN TO THE AREA NEXT THU. BUT IF THE QUEBEC CLOSED
LO IS MORE RESILIENT...THAT NEXT PLAINS LO COULD BE SHUNTED TO THE
SW. EXPECT RELATIVELY CHILLY WX THRU THE EXTENDED PERIOD WITH SUB
ZERO H85 TEMPS DOMINATING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 109 PM EDT FRI APR 22 2016
MVFR CLOUD DECK AT KSAW WILL ERODE SHORTLY AFT 18Z AS DRIER AIR WORKS
IN FROM NORTH OF THE LAKE. HIGH PRES BUILDING INTO THE REGION WILL
MAINTAIN VFR CONDITIONS FOR ALL TAF SITES THROUGH THE REST OF THE
FCST PERIOD. THERE WILL BE SOME INCREASE IN MID-HIGH CLOUDS INTO
KCMX AND KSAW LATE SAT MORNING AS WARM AIR PUSHES NORTH OF A FRONTAL
BOUNDARY OVER THE NORTHERN PLAINS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 457 AM EDT FRI APR 22 2016
NORTHERLY WINDS 15-25 KNOTS EARLY THIS MORNING ARE EXPECTED TO
DIMINISH TO 20 KTS OR LESS FRIDAY AFTERNOON THROUGH MOST OF SATURDAY
NIGHT AS A HIGH PRESSURE RIDGE CROSSES LAKE SUPERIOR. AS THE HIGH
EXITS TO THE EASTERN SEABOARD AND LOW PRESSURE DEVELOPS OVER THE
PLAINS ON SUNDAY, NORTHEAST WINDS WILL INCREASE TO 20-30 KTS SUNDAY
INTO MONDAY. THE STRONGEST WINDS WILL BE OVER WESTERN LAKE SUPERIOR
WHERE WINDS MAY APPROACH GALES AT TIMES. WINDS DIMINISH TO LESS THAN
20 KTS MONDAY NIGHT INTO TUESDAY AS HIGH PRESSURE MOVES BACK ACROSS
THE REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KC
AVIATION...VOSS
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
742 AM EDT FRI APR 22 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 457 AM EDT FRI APR 22 2016
WV IMAGERY AND RAP ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW INTO
THE NRN LAKES ON THE PERIPHERY OF A DEEP LOW INTO NRN HUDSON BAY.
LOW LEVEL CAA WITH NRLY WINDS INCREASED OVERNIGHT AS THE PRES
GRADIENT TIGHTENED BETWEEN HIGH PRESSURE INTO NRN ONTARIO AND TROUGH
OVER THE LOWER LAKES. CONVERGENT AND UPSLOPE FLOW INTO N CNTRL UPPER
MI COMBINED WITH LINGERING LOW LEVEL MOISTURE SUPPORTED SOME DZ/FZDZ
THAT HAS MIXED WITH LIGHT SNOW.
TODAY...EXPECT THAT THE LIGHT SNOW WILL TRANSITION TO MAINLY DZ/FZDZ
EARLY THIS MORNING AS THE DEEPER MOISTURE DEPARTS...LEAVING THE
MOIST LAYER WARMER THAN -8C. SATELLITE AND MODEL 925-900 MB RH FCST
TRENDS SUGGEST THAT THE LIGHT PCPN SHOULD DIMINISH OR END AROUND
12Z-14Z BUT THAT THE CLOUDS MAY PERSIST...MOVING OUT BTWN 15Z-18Z AS
HIGH PRESSURE WITH LOW LEVEL DRYING BUILDS IN. OTHERWISE...SUNSHINE
WITH 850 MB TEMPS NEAR -2C DURING THE AFTERNOON WILL HELP BOOST
INLAND TEMPS TO AROUND 50. OTHERWISE...NRLY FLOW OFF OF LAKE SUPERIOR
WILL LIMIT HIGH TEMPS CLOSER TO 40.
TONIGHT...ALTHOUGH WINDS WILL DIMINISH WITH THE SFC RIDGE OVER THE
AREA...MID CLOUDS MOVING IN OVERNIGHT WITH 700-500 MB WAA WILL KEEP
TEMPS FROM DROPPING OFF TOO FAR. TEMPS MAY STILL FALL INTO THE MID
20S CENTRAL AND EAST BEFORE THE CLOUDS MOVE IN. OTHERWISE...EXPECT
MIN READINGS IN THE LOWER 30S WEST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 351 AM EDT FRI APR 22 2016
LOOKS LIKE A CHILLY...ACTIVE WX PATTERN WL DOMINATE LATE THIS
WEEKEND INTO EARLY NEXT WEEK AS A VERY TIGHT BAROCLINIC ZN WL SETUP
ACRS THE UPR GREAT LKS UNDER THE CONFLUENCE ZN BTWN ARCTIC AIRSTREAM
IN CANADA AND AN ACTIVE POLAR BRANCH FLOW OVER THE NRN CONUS. SOME
MDT TO HEAVY PCPN IS LIKELY TO FALL OVER AT LEAST THE S HALF OF UPR
MI...WHICH WL BE CLOSER TO A STNRY FNT RUNNING W-E THRU THE UPR
MIDWEST. IF ENUF COLD AIR IN THE NNE FLOW BTWN BLDG HI PRES INTO NRN
ONTARIO AND THE LOWER PRES TO THE S ADVECTS INTO THE CWA AND THIS
AIR IS NOT EXCESSIVELY DRY...THERE COULD BE SOME ACCUMULATING WET SN
OVER MAINLY THE HIER TERRAIN OF NRN UPR MI ON SUN NGT INTO MON.
QUIETER BUT STILL RELATIVELY CHILLY WX WL BE THE RULE FOR MID WEEK.
SAT...UPR MI IS FCST TO BE DOMINATED BY WNW FLOW ALF BTWN UPR RDG
AXIS IN THE PLAINS AND UPR TROFFING IN ERN CANADA. ALTHOUGH MODELS
INDICATE A GOOD DEAL OF MID/HI CLDS RELATED TO WAA TO THE NE OF
SHARPENING FNT FM THE DAKOTAS INTO MN WL IMPACT THE CWA...SUSPECT
LINGERING LLVL DRY AIR ASSOCIATED WITH SLOWLY DEPARTING SFC HI PRES
WL KEEP THE CWA DRY. BEST CHC FOR SOME RAIN WL BE OVER THE NW CWA
CLOSER TO BAND OF STRONGER H7 FGEN TO THE NE OF SHARPENING FNT.
SAT NGT...MODELS IN FAIRLY GOOD AGREEMENT SHOWING MORE WIDESPREAD RA
DVLPG OVER THE CWA ESPECIALLY NEAR THE WI BORDER WITH SHARPENING
BAROCLINIC ZN/FGEN/INCRSG UPR DVGC IN RRQ OF 120KT H3 JET CORE
MOVING TO JUST S OF JAMES BAY BY 12Z SUN. WL CARRY THE HIER
CATEGORICAL POPS NEAR THE WI BORDER IN THE 06Z-12Z PERIOD.
SUN THRU MON...UPR MI IS FCST TO BE CLOSE TO SHARP BAROCLINIC ZN
UNDER CONFLUENCE ZN BTWN ARCTIC BRANCH NW FLOW DOMINATING QUEBEC AND
A WSW POLAR BRANCH FLOW OVER THE NRN CONUS. DESPITE THE UNFAVORABLE
LOOK OF THE CONFLUENT UPR FLOW WELL TO THE NE OF SHRTWV RIDING ENEWD
THRU THE NRN PLAINS WHICH WOULD TEND TO FAVOR DRY WX...MOST OF THE
MEDIUM RANGE MODELS GENERATE SOME MDT TO HEAVY PCPN OVER MAINLY THE
S HALF OF THE CWA. UPR DVGC IN RRQ OF 120KT H3 JET MAX JUST S OF
JAMES BAY AS WELL AS SHARP...PERSISTENT H85-7 FGEN N OF THE H85
WARM/STNRY FNT STRETCHING E ACRS WI FM LO IN THE NRN PLAINS AND
UNDER AXIS OF PWAT AOA AN INCH OVER THE SRN CWA LOOK TO BE THE
ENHANCEMENT FACTORS THAT WOULD OVERCOME THE UPR CONFLUENCE THAT WL
WEAKEN DISTURBANCES RIDING ENEWD TOWARD THE CWA AHEAD OF THE MAIN
SHRTWV TO THE SW. ALTHOUGH SOME OF THE COLDER MODELS` FCST SDNGS/
THERMAL FIELDS WITH H85 TEMPS AOB 0C INDICATE AT LEAST SOME OF THE
PCPN NEAR THE NRN EDGE OF THE BAND WL BE IN THE FORM OF SN...SHARP
GRADIENT IN SFC-H85 MSTR BTWN THE FNT AND CHILLY HI PRES BLDG INTO
NRN ONTARIO WL LIKELY BRING A RATHER SHARP NRN EDGE TO THE PCPN BAND
AND LIMIT THE COVERAGE OF SGNFT SN. BUT IF THE COLDER GUIDANCE IS
CORRECT AND THE LLVL DRYING IS NOT TOO AGGRESSIVE...NOT OUT OF THE
QUESTION THERE COULD BE SEVERAL INCHES OF WET...HEAVY SN OVER
PORTIONS OF THE NRN CWA MAINLY ON SUN NGT/MON MRNG AS STEADY LLVL NE
WINDS ADVECT COLDER AIR INTO THE LKS TO THE S OF THE ONTARIO HI PRES.
MON NGT THRU THU...AS THE HI PRES OVER NORTHERN ONTARIO BUILDS S
INTO THE UPR LKS UNDER CONFLUENT NW FLOW ALF BTWN UPR RDG AXIS
SHIFTING E FM THE PLAINS AND CLOSED UPR LO OVER QUEBEC...EXPECT
LINGERING PCPN TO END ON MON NGT...WITH THE HI PRES BRINGING DRY
WX/MOCLR SKIES ON TUE INTO WED. DEPENDING ON HOW QUICKLY THE QUEBEC
CLOSED LO WEAKENS AND WHETHER OR NOT THE UPR FLOW INTO THE GREAT LKS
TURNS MORE PROGRESSIVE...ANOTHER LO PRES MOVE ENE FM THE PLAINS
COULD BRING MORE PCPN TO THE AREA NEXT THU. BUT IF THE QUEBEC CLOSED
LO IS MORE RESILIENT...THAT NEXT PLAINS LO COULD BE SHUNTED TO THE
SW. EXPECT RELATIVELY CHILLY WX THRU THE EXTENDED PERIOD WITH SUB
ZERO H85 TEMPS DOMINATING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 741 AM EDT FRI APR 22 2016
EXPECT LOW CIGS TO GIVE WAY TO CLEARING BY LATE MORNING...PER
SATELLITE TRENDS AND FCST 900-925MB RH. SOME -FZDZ WILL ALSO BE
POSSIBLE AT SAW EARLY. CMX WILL CLEAR OUT EARLIEST AND IWD/SAW WITH
MORE PERSISTENT UPSLOPE FLOW SHOULD SEE CLEARING BY 14Z/16Z. HIGH
PRES BUILDING INTO THE REGION WILL BRING VFR CONDITIONS FOR THE REST
OF THE FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 457 AM EDT FRI APR 22 2016
NORTHERLY WINDS 15-25 KNOTS EARLY THIS MORNING ARE EXPECTED TO
DIMINISH TO 20 KTS OR LESS FRIDAY AFTERNOON THROUGH MOST OF SATURDAY
NIGHT AS A HIGH PRESSURE RIDGE CROSSES LAKE SUPERIOR. AS THE HIGH
EXITS TO THE EASTERN SEABOARD AND LOW PRESSURE DEVELOPS OVER THE
PLAINS ON SUNDAY, NORTHEAST WINDS WILL INCREASE TO 20-30 KTS SUNDAY
INTO MONDAY. THE STRONGEST WINDS WILL BE OVER WESTERN LAKE SUPERIOR
WHERE WINDS MAY APPROACH GALES AT TIMES. WINDS DIMINISH TO LESS THAN
20 KTS MONDAY NIGHT INTO TUESDAY AS HIGH PRESSURE MOVES BACK ACROSS
THE REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KC
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
459 AM EDT FRI APR 22 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 457 AM EDT FRI APR 22 2016
WV IMAGERY AND RAP ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW INTO
THE NRN LAKES ON THE PERIPHERY OF A DEEP LOW INTO NRN HUDSON BAY.
LOW LEVEL CAA WITH NRLY WINDS INCREASED OVERNIGHT AS THE PRES
GRADIENT TIGHTENED BETWEEN HIGH PRESSURE INTO NRN ONTARIO AND TROUGH
OVER THE LOWER LAKES. CONVERGENT AND UPSLOPE FLOW INTO N CNTRL UPPER
MI COMBINED WITH LINGERING LOW LEVEL MOISTURE SUPPORTED SOME DZ/FZDZ
THAT HAS MIXED WITH LIGHT SNOW.
TODAY...EXPECT THAT THE LIGHT SNOW WILL TRANSITION TO MAINLY DZ/FZDZ
EARLY THIS MORNING AS THE DEEPER MOISTURE DEPARTS...LEAVING THE
MOIST LAYER WARMER THAN -8C. SATELLITE AND MODEL 925-900 MB RH FCST
TRENDS SUGGEST THAT THE LIGHT PCPN SHOULD DIMINISH OR END AROUND
12Z-14Z BUT THAT THE CLOUDS MAY PERSIST...MOVING OUT BTWN 15Z-18Z AS
HIGH PRESSURE WITH LOW LEVEL DRYING BUILDS IN. OTHERWISE...SUNSHINE
WITH 850 MB TEMPS NEAR -2C DURING THE AFTERNOON WILL HELP BOOST
INLAND TEMPS TO AROUND 50. OTHERWISE...NRLY FLOW OFF OF LAKE SUPERIOR
WILL LIMIT HIGH TEMPS CLOSER TO 40.
TONIGHT...ALTHOUGH WINDS WILL DIMINISH WITH THE SFC RIDGE OVER THE
AREA...MID CLOUDS MOVING IN OVERNIGHT WITH 700-500 MB WAA WILL KEEP
TEMPS FROM DROPPING OFF TOO FAR. TEMPS MAY STILL FALL INTO THE MID
20S CENTRAL AND EAST BEFORE THE CLOUDS MOVE IN. OTHERWISE...EXPECT
MIN READINGS IN THE LOWER 30S WEST.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 351 AM EDT FRI APR 22 2016
LOOKS LIKE A CHILLY...ACTIVE WX PATTERN WL DOMINATE LATE THIS
WEEKEND INTO EARLY NEXT WEEK AS A VERY TIGHT BAROCLINIC ZN WL SETUP
ACRS THE UPR GREAT LKS UNDER THE CONFLUENCE ZN BTWN ARCTIC AIRSTREAM
IN CANADA AND AN ACTIVE POLAR BRANCH FLOW OVER THE NRN CONUS. SOME
MDT TO HEAVY PCPN IS LIKELY TO FALL OVER AT LEAST THE S HALF OF UPR
MI...WHICH WL BE CLOSER TO A STNRY FNT RUNNING W-E THRU THE UPR
MIDWEST. IF ENUF COLD AIR IN THE NNE FLOW BTWN BLDG HI PRES INTO NRN
ONTARIO AND THE LOWER PRES TO THE S ADVECTS INTO THE CWA AND THIS
AIR IS NOT EXCESSIVELY DRY...THERE COULD BE SOME ACCUMULATING WET SN
OVER MAINLY THE HIER TERRAIN OF NRN UPR MI ON SUN NGT INTO MON.
QUIETER BUT STILL RELATIVELY CHILLY WX WL BE THE RULE FOR MID WEEK.
SAT...UPR MI IS FCST TO BE DOMINATED BY WNW FLOW ALF BTWN UPR RDG
AXIS IN THE PLAINS AND UPR TROFFING IN ERN CANADA. ALTHOUGH MODELS
INDICATE A GOOD DEAL OF MID/HI CLDS RELATED TO WAA TO THE NE OF
SHARPENING FNT FM THE DAKOTAS INTO MN WL IMPACT THE CWA...SUSPECT
LINGERING LLVL DRY AIR ASSOCIATED WITH SLOWLY DEPARTING SFC HI PRES
WL KEEP THE CWA DRY. BEST CHC FOR SOME RAIN WL BE OVER THE NW CWA
CLOSER TO BAND OF STRONGER H7 FGEN TO THE NE OF SHARPENING FNT.
SAT NGT...MODELS IN FAIRLY GOOD AGREEMENT SHOWING MORE WIDESPREAD RA
DVLPG OVER THE CWA ESPECIALLY NEAR THE WI BORDER WITH SHARPENING
BAROCLINIC ZN/FGEN/INCRSG UPR DVGC IN RRQ OF 120KT H3 JET CORE
MOVING TO JUST S OF JAMES BAY BY 12Z SUN. WL CARRY THE HIER
CATEGORICAL POPS NEAR THE WI BORDER IN THE 06Z-12Z PERIOD.
SUN THRU MON...UPR MI IS FCST TO BE CLOSE TO SHARP BAROCLINIC ZN
UNDER CONFLUENCE ZN BTWN ARCTIC BRANCH NW FLOW DOMINATING QUEBEC AND
A WSW POLAR BRANCH FLOW OVER THE NRN CONUS. DESPITE THE UNFAVORABLE
LOOK OF THE CONFLUENT UPR FLOW WELL TO THE NE OF SHRTWV RIDING ENEWD
THRU THE NRN PLAINS WHICH WOULD TEND TO FAVOR DRY WX...MOST OF THE
MEDIUM RANGE MODELS GENERATE SOME MDT TO HEAVY PCPN OVER MAINLY THE
S HALF OF THE CWA. UPR DVGC IN RRQ OF 120KT H3 JET MAX JUST S OF
JAMES BAY AS WELL AS SHARP...PERSISTENT H85-7 FGEN N OF THE H85
WARM/STNRY FNT STRETCHING E ACRS WI FM LO IN THE NRN PLAINS AND
UNDER AXIS OF PWAT AOA AN INCH OVER THE SRN CWA LOOK TO BE THE
ENHANCEMENT FACTORS THAT WOULD OVERCOME THE UPR CONFLUENCE THAT WL
WEAKEN DISTURBANCES RIDING ENEWD TOWARD THE CWA AHEAD OF THE MAIN
SHRTWV TO THE SW. ALTHOUGH SOME OF THE COLDER MODELS` FCST SDNGS/
THERMAL FIELDS WITH H85 TEMPS AOB 0C INDICATE AT LEAST SOME OF THE
PCPN NEAR THE NRN EDGE OF THE BAND WL BE IN THE FORM OF SN...SHARP
GRADIENT IN SFC-H85 MSTR BTWN THE FNT AND CHILLY HI PRES BLDG INTO
NRN ONTARIO WL LIKELY BRING A RATHER SHARP NRN EDGE TO THE PCPN BAND
AND LIMIT THE COVERAGE OF SGNFT SN. BUT IF THE COLDER GUIDANCE IS
CORRECT AND THE LLVL DRYING IS NOT TOO AGGRESSIVE...NOT OUT OF THE
QUESTION THERE COULD BE SEVERAL INCHES OF WET...HEAVY SN OVER
PORTIONS OF THE NRN CWA MAINLY ON SUN NGT/MON MRNG AS STEADY LLVL NE
WINDS ADVECT COLDER AIR INTO THE LKS TO THE S OF THE ONTARIO HI PRES.
MON NGT THRU THU...AS THE HI PRES OVER NORTHERN ONTARIO BUILDS S
INTO THE UPR LKS UNDER CONFLUENT NW FLOW ALF BTWN UPR RDG AXIS
SHIFTING E FM THE PLAINS AND CLOSED UPR LO OVER QUEBEC...EXPECT
LINGERING PCPN TO END ON MON NGT...WITH THE HI PRES BRINGING DRY
WX/MOCLR SKIES ON TUE INTO WED. DEPENDING ON HOW QUICKLY THE QUEBEC
CLOSED LO WEAKENS AND WHETHER OR NOT THE UPR FLOW INTO THE GREAT LKS
TURNS MORE PROGRESSIVE...ANOTHER LO PRES MOVE ENE FM THE PLAINS
COULD BRING MORE PCPN TO THE AREA NEXT THU. BUT IF THE QUEBEC CLOSED
LO IS MORE RESILIENT...THAT NEXT PLAINS LO COULD BE SHUNTED TO THE
SW. EXPECT RELATIVELY CHILLY WX THRU THE EXTENDED PERIOD WITH SUB
ZERO H85 TEMPS DOMINATING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 121 AM EDT FRI APR 22 2016
PRECIPITATION HAS MOSTLY ENDED IN THE WAKE OF YESTERDAY/S COLD
FROPA BUT A COOL/MOIST NORTHERLY FLOW REMAINS AND WITH ADDITIONAL
MOISTURE OFF LK SUPERIOR CEILINGS HAVE LOWERED TO LOW END MVFR TO
IFR THIS EVENING. EXPECT SLOW IMPROVEMENT FOR THE OVERNIGHT
HOURS WITH SKIES CLEARING OUT FRIDAY MORNING AS HIGH PRES BUILDS IN
FROM NW OF LAKE SUPERIOR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 457 AM EDT FRI APR 22 2016
NORTHERLY WINDS 15-25 KNOTS EARLY THIS MORNING ARE EXPECTED TO
DIMINISH TO 20 KTS OR LESS FRIDAY AFTERNOON THROUGH MOST OF SATURDAY
NIGHT AS A HIGH PRESSURE RIDGE CROSSES LAKE SUPERIOR. AS THE HIGH
EXITS TO THE EASTERN SEABOARD AND LOW PRESSURE DEVELOPS OVER THE
PLAINS ON SUNDAY, NORTHEAST WINDS WILL INCREASE TO 20-30 KTS SUNDAY
INTO MONDAY. THE STRONGEST WINDS WILL BE OVER WESTERN LAKE SUPERIOR
WHERE WINDS MAY APPROACH GALES AT TIMES. WINDS DIMINISH TO LESS THAN
20 KTS MONDAY NIGHT INTO TUESDAY AS HIGH PRESSURE MOVES BACK ACROSS
THE REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KC
AVIATION...VOSS
MARINE...JLB
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1207 AM EDT FRI APR 22 2016
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 327 PM EDT THU APR 21 2016
AFTER SHOWERS AND ISOLATED THUNDERSTORMS EXIT THE AREA EARLY
TONIGHT...CHANCES FOR SHOWERS AND THUNDERSTORMS RETURN SUNDAY AND
CONTINUE WELL INTO NEXT WEEK. SUNDAY WILL BE WARM WITH TEMPERATURES
APPROACHING 70 IN SOME SPOTS. AFTERWARDS...HIGHS WILL BE NEAR
OR SLIGHTLY ABOVE NORMAL WITH HIGHS IN THE LOWER TO MID 60S.
&&
.UPDATE...
ISSUED AT 936 PM EDT THU APR 21 2016
WE HAVE UPDATED THE FCST THIS EVENING TO FRESHEN UP PCPN
TRENDS...PULL THUNDER...AND ADD MORE FOG TO THE FCST AREA-WIDE.
A FEW STORMS TRIED TO MAKE IT UP INTO THE AREA FROM THE S/SW...BUT
COULDN/T QUITE MAKE IT WITH THE LACK OF INSTABILITY UP THIS WAY
WITH ALL OF THE CLOUD COVER TODAY. MODELS ALL SHOW THE INSTABILITY
WILL BE STEADILY ON THE WANE THROUGH THE NIGHT...SO WE PULLED IT
ALTOGETHER.
A FEW SHOWERS ARE AFFECTING THE SE CORNER OF THE CWFA THIS EVENING
LEFT OVER FROM CONVECTION FROM EARLIER ACROSS INDIANA. THESE WILL
BE MOVING OUT SOON...LEAVING ONLY A SMALL CHC OF A SHOWER
OVERNIGHT AS THE SECONDARY FRONT DROPS THROUGH THE AREA.
FOG LOOKS TO BE A LITTLE MORE LIKELY...ESPECIALLY WITH SOME
CLEARING WORKING THROUGH THE SRN TWO THIRDS OF THE CWFA THIS
EVENING. WINDS ARE STILL RELATIVELY LIGHT...AND COULD REMAIN THAT
WAY RIGHT AT THE SFC ALL NIGHT. SOME BETTER MIXING ALOFT WILL MOVE
IN BEHIND THE FRONT. WE EXPECT SOME FOG DEVELOPING...WITH THE
BIGGER ISSUE BEING STRATUS EXPECTED TO MOVE IN FROM THE NORTH
OVERNIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 327 PM EDT THU APR 21 2016
EXPERIMENTAL HRRR GUIDANCE IS LOOKING ON TRACK AS CLEARING HAS
SPREAD INTO EXTREME SOUTHWEST LOWER MI AND A THUNDERSTORM ALREADY
HAS DEVELOPED OVER NORTHWEST INDIANA. BASED ON EXPECTED MOVEMENT
TO THE NORTHEAST...WE STILL EXPECT THE BEST CHANCES FOR THUNDERSTORMS
WILL BE SOUTH OF I-96 AND EAST OF KALAMAZOO MAINLY BEFORE MIDNIGHT.
AFTER THIS EXPECT AT LEAST SOME PATCHY FOG NEAR THE I-94 CORRIDOR
THE REST OF THE NIGHT.
AFTER TONIGHT...FORECAST CONCERNS ARE MINIMAL WITH RAIN SHOWERS
APPROACHING FROM THE NORTHWEST ON SATURDAY NIGHT.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 327 PM EDT THU APR 21 2016
A STATIONARY FRONT IS STILL EXPECTED TO SLIDE SLOWLY SOUTH THROUGH
THE CWA SUNDAY INTO MONDAY NIGHT. THIS FRONT WILL HAVE A SOLID GULF
MOISTURE CONNECTION AND THE OVER RIDING ACROSS THIS FRONT SHOULD
PRODUCE A FAIR AMOUNT OF RAIN. IT APPEARS MOST AREAS SHOULD GET A
AROUND AN INCH OF RAIN. THE STEADIEST RAINS SHOULD OCCUR ACROSS
CENTRAL LOWER WHERE THE BEST LIFT PERSISTS ACROSS THE FRONT...AND
OVER AN INCH OF RAIN CERTAINLY SEEMS POSSIBLE HERE. A BIT LIGHTER
RAINS ARE EXPECTED TOWARD I-94. A FEW CLAPS OF THUNDER WILL BE
POSSIBLE BUT NO SEVERE WEATHER IS EXPECTED AT THIS TIME. THE AREA
SHOULD DRY OUT INTO TUESDAY AS A WAVE OF LOW PRESSURE SLIDES ALONG
THE FRONT AND HEADS EAST.
HOWEVER THE DRY SPELL APPEARS BRIEF AS MORE RAIN CHANCES RETURN FOR
WEDNESDAY AND THURSDAY WITH ANOTHER WAVE OF LOW PRESSURE MOVING
ACROSS THE OHIO VALLEY. SIMILAR PATTERN WITH A GOOD CHANCE OF
RAIN...BUT MINIMAL CHANCES FOR SEVERE STORMS.
WE WILL REMAIN MILD UNTIL THE FRONT COMES THROUGH...WITH A COOLER
PERIOD FOR TUESDAY AND WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1207 AM EDT FRI APR 22 2016
WIDESPREAD IFR/LIFR CONDITIONS IN FOG AND LOW CLOUDS ARE LIKELY
OVERNIGHT DUE TO MOIST BOUNDARY LAYER CONDITIONS WITH DEW PTS IN
THE LOWER 50S AND LIGHT SFC WINDS. THE LOWER CIGS/VSBYS WILL
LINGER THROUGH ABOUT 15Z FRIDAY THEN LIFT TO MVFR TO VFR LEVELS IN
THE AFTERNOON AS WINDS INCREASE OUT OF THE NORTH TO AROUND 10 KTS
AND SEND DRIER AIR INTO THE REGION. VFR LIKELY ON FRIDAY NIGHT.
&&
.MARINE...
ISSUED AT 327 PM EDT THU APR 21 2016
FOG HAS BECOME CONSIDERABLY THICKER IN THE LAST COUPLE HOURS SO IN
COORDINATION WITH IWX HAVE HOISTED A MARINE DENSE FOG ADVISORY.
FOG WILL GET SWEPT OUT OVERNIGHT WHEN STRONG NORTH WINDS SPREAD
SOUTH ACROSS LAKE MICHIGAN. RAPIDLY GROWING WAVES WITH THE
STRONGER WINDS AND A VERY FAVORABLE LONG FETCH WILL GIVE US SMALL
CRAFT ADVISORY CONDITIONS QUICKLY FRIDAY MORNING SO HAVE ALSO
ISSUED A SMALL CRAFT ADVISORY WITH THIS PACKAGE.
&&
.HYDROLOGY...
ISSUED AT 158 PM EDT THU APR 21 2016
RAINFALL LAST NIGHT AND TODAY HAS BEEN LIGHT IN NATURE... WITH FEW
TOTALS EXCEEDING A QUARTER INCH. LEVELS ON MAIN STEM RIVERS CONTINUE
A GRADUAL DECLINE... BUT WE HAVE BEEN SEEING RISES ON SMALLER RIVERS
AND CREEKS. NO FLOODING IN ANTICIPATED TODAY OR TOMORROW.
AFTER A QUIET FRIDAY AND SATURDAY... SUNDAY THROUGH THE REST OF NEXT
WEEK LOOKS FAIRLY ACTIVE. A WIDESPREAD INCH OF RAINFALL IS CERTAINLY
POSSIBLE. RIVERS REMAIN ELEVATED... SO WE COULD SEE SOME RISE ABOVE
BANKFULL AND PRODUCE MINOR FLOODING IN LOWLAND AREAS NEXT WEEK.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR LMZ844>849.
SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 2 AM EDT SATURDAY
FOR LMZ844>849.
&&
$$
UPDATE...NJJ
SYNOPSIS...TJT
SHORT TERM...TJT
LONG TERM...JK
AVIATION...MEADE
HYDROLOGY...EBW
MARINE...TJT
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1047 PM CDT SAT APR 23 2016
.Short Term...(This Evening through Monday Night)
Issued at 309 PM CDT SAT APR 23 2016
Short Term (Tonight through Monday night):
The main concern in the short term will be the potential for a few
strong and isolated severe storms on Sunday evening into Sunday
night. Tonight, however will be much less interesting and quite
pleasant as modest southerly winds will hold temperatures in the mid
50s to lower 60s. The system, an upper level trough, that will bring
thunderstorms to the area Sunday will move from western Wyoming to
near the WY/SD/NE by Saturday night. This will force a cold front into
the western Plains. Thunderstorms will develop along this front
tonight across western Kansas. This storms will progress across
Kansas overnight enhanced by a 50-60kt SSWly nocturnal LLJ. By early
Sunday morning the LLJ will veer to the southwest and storms will
begin to approach northeastern KS and northwestern MO. However,
these storms will be weakening as they approach and there may just
be a few isolated storms or residual shower to make it into the
extreme NW CWA Sunday morning. However, by Sunday afternoon, a dry
line will exist across central Kansas with the attendant cold front
lagging to the west across the western High Plains. Thunderstorms
are expected to develop out ahead of the cold front across central
Kansas during the afternoon and move eastward. These storms will
have the potential to be strong with perhaps isolated severe storms
possible mainly across northwestern MO/northeastern KS where
dewpoints will be near 60 degrees, modest instability of 500-
800J/kg, and steep mid-level lapse rates will exist. However, shear
is not impressive and as previously mentioned instability is merely
modest. Consequently, strong storms will be possible and perhaps
even a marginally severe storm capable of producing large hail or
damaging winds. Storms will weaken Sunday night as storms move into
a more stable environment and the upper level trough continues to
weak as it moves into the Upper Midwest. On Monday, the cold front
associated with the upper level system will sag through the area.
However, will little forcing the front will sag through the area
with little activity expected. The best chance for storms would
occur head of the front where modest instability will reside. Monday
night the cold front will sink south of the area and become
stationary. A few thunderstorms may develop north of the stationary
boundary Monday as a SW 40kt LLJ overrides the boundary. These
thunderstorms may affect the southern CWA depending on the location
of the front.
.Long Term...(Tuesday through Saturday)
Issued at 309 PM CDT SAT APR 23 2016
Tuesday evening and Wednesday will bring another round of showers
and possibly severe thunderstorms to the CWA. The most recent NAM
and GFS runs show Tuesday morning and early afternoon warm and humid
with precipitation mainly staying just south of the WFO. A negatively
tilted low pressure trough stations itself over eastern CO/western KS
Tuesday afternoon. A cold front will move east through Kansas
Wednesday afternoon, and an associated warm front will be located E-W
through our forecast area late Tuesday bringing low- level moisture
with it. Dew point temperatures will range from low 50s north of the
front spreading south to the mid-60s. We will also have decent
instability and shear with CAPE values around 1000-2000 J/kg and
30-50 kt 0-6 km bulk shear. A combination of high CAPE and shear may
lead to potentially severe thunderstorms ahead of the cold front. The
development and location of severe weather will depend on the timing
of convection and the frontal passage, which will become more clear
as we get closer to the event. For now, the GFS and Euro models show
precipitation starting in eastern KS and moving east through the WFO
late Tuesday night through Wednesday morning. Convection could
continue throughout Wednesday as CAPE values are expected to stay
above 1000 J/kg throughout Wednesday afternoon.
High temperatures will continue to be in the mid 70s through
Wednesday, but will drop to the mid-high 60s for Thursday and Friday
after the cold front passes. Low temperatures will drop Thursday and
Friday mornings to the high 40s to low 50s. Thursday is expected to
be dry before another upper low system may cause more precipitation
late Friday into Saturday.
&&
.Aviation...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1046 PM CDT SAT APR 23 2016
VFR conditions expected through much of the fcst period. Latest
model runs suggesting the bulk of thunderstorm activity will remain
west of the forecast area. Cannot rule out some isolated convection
holding itself together as it moves east off the dryline in central
Kansas...but activity will be moving into a more and more unfavorable
environment with further eastward progress. In any event...have
inserted a VCTS mention for STJ...and later updates can address the
KC terminals if trends begin to change. The other main concern
remains the likelihood for LLWS early this morning thanks to a strong
southwesterly low-level jet...and have maintained mention for all
terminals with the 06z package. Meanwhile...southerly winds of 10-15
kts overnight will increase after 16z on Sunday with gusts up to 30
kts possible during the afternoon hours.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Short Term...73
Long Term...Chandler/CDB
Aviation...32
[top]
Area Forecast Discussion...Updated
National Weather Service Saint Louis MO
921 PM CDT SAT APR 23 2016
.UPDATE...
Issued at 921 PM CDT Sat Apr 23 2016
Going dry forecast the rest of the night still looks good as upper
ridge moves over the area allowing for only a few high clouds to
drift across the area. Still may be some patchy fog tonight, but
think this will be held in check by the wind which should stay up
tonight as the pressure gradient continues to tighten. Only made
minor adjustments to lows based on going temperature trends.
Britt
&&
.SHORT TERM... (Through Late Tonight)
Issued at 255 PM CDT Sat Apr 23 2016
Surface ridge extending from MI southwest into eastern MO will move
eastward. The stratus clouds across southeast IL should continue to
dissipate late this afternoon. Few-scattered diurnal cumulus
clouds, especially across parts of northeast and central MO will
dissipate early this evening with the loss of daytime heating.
Mainly just a little high level cloudiness tonight. Lows tonight
will be warmer than the previous night, mainly due to southeast
surface winds on the backside of the surface ridge. The warmest
temperatures will be across central MO with the coolest temperatures
in southwest IL. Lows tonight will be about 5 to 10 degrees above
normal for late April.
GKS
.LONG TERM... (Sunday through Next Saturday)
Issued at 255 PM CDT Sat Apr 23 2016
Dry and warmer weather to persist on Sunday, but will see an
increase in high clouds as next weather system approaches region.
With gusty south winds will see highs in the upper 70s to low 80s.
Sunday night rain chances to approach region, but models are a bit
slower with onset, so lowered pops just a bit. Then Monday through
Tuesday, frontal boundary to slowly slide south through area with
mainly scattered showers and thunderstorms. Front to stall out
across southern Missouri on Tuesday. Highs will be in the upper 70s
to low 80s on Monday, then dip down into the low 70s to low 80s
Tuesday and Wednesday.
Decent instability north of front Tuesday night, so could see
elevated activity develop and slide along boundary on nose of decent
low level jet. Large hail would be the main threat with this round
of storms.
Models are still indicating decent instability, CAPES in excess of
1500 J/kg and shear with system Wednesday afternoon, Wednesday night
as warm front lifts north through forecast area. All of this still
points to our first real potential severe weather day this spring,
but a lot can happen in 5 days. Stay tuned to further updates.
With everything a bit slower, main cold front to slide through early
on Thursday with precipitation tapering off to just slight chance
pops through Friday. Then extended models showing next system
lifting northeast towards forecast area Friday night and Saturday
with increasing chances of showers and thunderstorms once again.
Once system exits region on Thursday, will see precipitation taper
off. Even though it will be a bit cooler Thursday, highs will still
be a bit above normal in the mid 60s to upper 70s. Extended models
beginning to indicate another system approaching region on Friday,
but timing is hard to pin down. So for now kept slight chance pops.
Byrd
&&
.AVIATION... (For the 00z TAFs through 00z Sunday Evening)
Issued at 650 PM CDT Sat Apr 23 2016
Dry and VFR conditions are expected at the terminals. There may be
some patchy fog late tonight and early Sunday over southern
Illinois and southeast Missouri. Low level wind shear is still
possible at KUIN and KCOU between 09-15Z as a 35-40kt low level
jet sets up between 1000-2000 feet. This threat will end by mid
morning as mixing begins and the surface winds begin to pick up.
Do expect some gusts above 20kts during the late morning and
afternoon hours.
Specifics for KSTL: Dry and VFR conditions are expected the next
30 hours. Southerly winds will increase after 18Z on Sunday
afternoon with wind gusts over 20kts.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
705 PM CDT SAT APR 23 2016
.SHORT TERM... (Through Late Tonight)
Issued at 255 PM CDT Sat Apr 23 2016
Surface ridge extending from MI southwest into eastern MO will move
eastward. The stratus clouds across southeast IL should continue to
dissipate late this afternoon. Few-scattered diurnal cumulus
clouds, especially across parts of northeast and central MO will
dissipate early this evening with the loss of daytime heating.
Mainly just a little high level cloudiness tonight. Lows tonight
will be warmer than the previous night, mainly due to southeast
surface winds on the backside of the surface ridge. The warmest
temperatures will be across central MO with the coolest temperatures
in southwest IL. Lows tonight will be about 5 to 10 degrees above
normal for late April.
GKS
.LONG TERM... (Sunday through Next Saturday)
Issued at 255 PM CDT Sat Apr 23 2016
Dry and warmer weather to persist on Sunday, but will see an
increase in high clouds as next weather system approaches region.
With gusty south winds will see highs in the upper 70s to low 80s.
Sunday night rain chances to approach region, but models are a bit
slower with onset, so lowered pops just a bit. Then Monday through
Tuesday, frontal boundary to slowly slide south through area with
mainly scattered showers and thunderstorms. Front to stall out
across southern Missouri on Tuesday. Highs will be in the upper 70s
to low 80s on Monday, then dip down into the low 70s to low 80s
Tuesday and Wednesday.
Decent instability north of front Tuesday night, so could see
elevated activity develop and slide along boundary on nose of decent
low level jet. Large hail would be the main threat with this round
of storms.
Models are still indicating decent instability, CAPES in excess of
1500 J/kg and shear with system Wednesday afternoon, Wednesday night
as warm front lifts north through forecast area. All of this still
points to our first real potential severe weather day this spring,
but a lot can happen in 5 days. Stay tuned to further updates.
With everything a bit slower, main cold front to slide through early
on Thursday with precipitation tapering off to just slight chance
pops through Friday. Then extended models showing next system
lifting northeast towards forecast area Friday night and Saturday
with increasing chances of showers and thunderstorms once again.
Once system exits region on Thursday, will see precipitation taper
off. Even though it will be a bit cooler Thursday, highs will still
be a bit above normal in the mid 60s to upper 70s. Extended models
beginning to indicate another system approaching region on Friday,
but timing is hard to pin down. So for now kept slight chance pops.
Byrd
&&
.AVIATION... (For the 00z TAFs through 00z Sunday Evening)
Issued at 650 PM CDT Sat Apr 23 2016
Dry and VFR conditions are expected at the terminals. There may be
some patchy fog late tonight and early Sunday over southern
Illinois and southeast Missouri. Low level wind shear is still
possible at KUIN and KCOU between 09-15Z as a 35-40kt low level
jet sets up between 1000-2000 feet. This threat will end by mid
morning as mixing begins and the surface winds begin to pick up.
Do expect some gusts above 20kts during the late morning and
afternoon hours.
Specifics for KSTL: Dry and VFR conditions are expected the next
30 hours. Southerly winds will increase after 18Z on Sunday
afternoon with wind gusts over 20kts.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
629 PM CDT SAT APR 23 2016
.Short Term...(This Evening through Monday Night)
Issued at 309 PM CDT SAT APR 23 2016
Short Term (Tonight through Monday night):
The main concern in the short term will be the potential for a few
strong and isolated severe storms on Sunday evening into Sunday
night. Tonight, however will be much less interesting and quite
pleasant as modest southerly winds will hold temperatures in the mid
50s to lower 60s. The system, an upper level trough, that will bring
thunderstorms to the area Sunday will move from western Wyoming to
near the WY/SD/NE by Saturday night. This will force a cold front into
the western Plains. Thunderstorms will develop along this front
tonight across western Kansas. This storms will progress across
Kansas overnight enhanced by a 50-60kt SSWly nocturnal LLJ. By early
Sunday morning the LLJ will veer to the southwest and storms will
begin to approach northeastern KS and northwestern MO. However,
these storms will be weakening as they approach and there may just
be a few isolated storms or residual shower to make it into the
extreme NW CWA Sunday morning. However, by Sunday afternoon, a dry
line will exist across central Kansas with the attendant cold front
lagging to the west across the western High Plains. Thunderstorms
are expected to develop out ahead of the cold front across central
Kansas during the afternoon and move eastward. These storms will
have the potential to be strong with perhaps isolated severe storms
possible mainly across northwestern MO/northeastern KS where
dewpoints will be near 60 degrees, modest instability of 500-
800J/kg, and steep mid-level lapse rates will exist. However, shear
is not impressive and as previously mentioned instability is merely
modest. Consequently, strong storms will be possible and perhaps
even a marginally severe storm capable of producing large hail or
damaging winds. Storms will weaken Sunday night as storms move into
a more stable environment and the upper level trough continues to
weak as it moves into the Upper Midwest. On Monday, the cold front
associated with the upper level system will sag through the area.
However, will little forcing the front will sag through the area
with little activity expected. The best chance for storms would
occur head of the front where modest instability will reside. Monday
night the cold front will sink south of the area and become
stationary. A few thunderstorms may develop north of the stationary
boundary Monday as a SW 40kt LLJ overrides the boundary. These
thunderstorms may affect the southern CWA depending on the location
of the front.
.Long Term...(Tuesday through Saturday)
Issued at 309 PM CDT SAT APR 23 2016
Tuesday evening and Wednesday will bring another round of showers
and possibly severe thunderstorms to the CWA. The most recent NAM
and GFS runs show Tuesday morning and early afternoon warm and humid
with precipitation mainly staying just south of the WFO. A negatively
tilted low pressure trough stations itself over eastern CO/western KS
Tuesday afternoon. A cold front will move east through Kansas
Wednesday afternoon, and an associated warm front will be located E-W
through our forecast area late Tuesday bringing low- level moisture
with it. Dew point temperatures will range from low 50s north of the
front spreading south to the mid-60s. We will also have decent
instability and shear with CAPE values around 1000-2000 J/kg and
30-50 kt 0-6 km bulk shear. A combination of high CAPE and shear may
lead to potentially severe thunderstorms ahead of the cold front. The
development and location of severe weather will depend on the timing
of convection and the frontal passage, which will become more clear
as we get closer to the event. For now, the GFS and Euro models show
precipitation starting in eastern KS and moving east through the WFO
late Tuesday night through Wednesday morning. Convection could
continue throughout Wednesday as CAPE values are expected to stay
above 1000 J/kg throughout Wednesday afternoon.
High temperatures will continue to be in the mid 70s through
Wednesday, but will drop to the mid-high 60s for Thursday and Friday
after the cold front passes. Low temperatures will drop Thursday and
Friday mornings to the high 40s to low 50s. Thursday is expected to
be dry before another upper low system may cause more precipitation
late Friday into Saturday.
&&
.Aviation...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 629 PM CDT SAT APR 23 2016
VFR conditions anticipated through the fcst period with modest south
winds of 10-15 kts expected through the overnight before increasing
after 16z. Further aloft...a strong southwesterly low-level jet of
roughly 45 kts will lead to increasing LLWS concerns after 06z and a
mention has been added for all forecast locations. Precip chances in
the form of shwrs/storms look to increase after 21z...however the
mostly likely location right now appears to be STJ based on expected
dryline configuration. Will consider adding further south with the
next forecast issuance.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Short Term...73
Long Term...Chandler/CDB
Aviation...32
[top]
Area Forecast Discussion
National Weather Service Springfield MO
616 PM CDT SAT APR 23 2016
...00z Aviation Update...
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 616 PM CDT Sat Apr 23 2016
VFR conditions will again persist through this TAF cycle. Winds
have become southerly (as advertised) during the day today.
Surface winds will steadily increase through Sunday ahead of a
passing system over the plains. Gusty southerly winds can be
expected for SGF and JLN by Sunday afternoon and should continue
through the end of the period.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Frye
Area Forecast Discussion
National Weather Service Springfield MO
616 PM CDT SAT APR 23 2016
...00z Aviation Update...
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 616 PM CDT Sat Apr 23 2016
VFR conditions will again persist through this TAF cycle. Winds
have become southerly (as advertised) during the day today.
Surface winds will steadily increase through Sunday ahead of a
passing system over the plains. Gusty southerly winds can be
expected for SGF and JLN by Sunday afternoon and should continue
through the end of the period.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Frye
Area Forecast Discussion
National Weather Service Springfield MO
328 PM CDT SAT APR 23 2016
...Beautiful Weather This Weekend...Increasing Confidence for
Strong to Severe Storms Next Week...
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1159 AM CDT Sat Apr 23 2016
VFR conditions are expected through the period as surface high
pressure continues to drift eastward and an upper level ridge
moves across the area. Main forecast concern is gusty winds
beginning after sunrise on Sunday as the next approaching system
begins to tighten up the surface pressure gradient. Winds should
develop gusts after 13z at KSGF/KJLN but believe that it will be
later in the afternoon...after the end of the forecast
period...for KBBG.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Gaede
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
310 PM CDT SAT APR 23 2016
.Short Term...(This Evening through Monday Night)
Issued at 309 PM CDT SAT APR 23 2016
Short Term (Tonight through Monday night):
The main concern in the short term will be the potential for a few
strong and isolated severe storms on Sunday evening into Sunday
night. Tonight, however will be much less interesting and quite
pleasant as modest southerly winds will hold temperatures in the mid
50s to lower 60s. The system, an upper level trough, that will bring
thunderstorms to the area Sunday will move from western Wyoming to
near the WY/SD/NE by Saturday night. This will force a cold front into
the western Plains. Thunderstorms will develop along this front
tonight across western Kansas. This storms will progress across
Kansas overnight enhanced by a 50-60kt SSWly nocturnal LLJ. By early
Sunday morning the LLJ will veer to the southwest and storms will
begin to approach northeastern KS and northwestern MO. However,
these storms will be weakening as they approach and there may just
be a few isolated storms or residual shower to make it into the
extreme NW CWA Sunday morning. However, by Sunday afternoon, a dry
line will exist across central Kansas with the attendant cold front
lagging to the west across the western High Plains. Thunderstorms
are expected to develop out ahead of the cold front across central
Kansas during the afternoon and move eastward. These storms will
have the potential to be strong with perhaps isolated severe storms
possible mainly across northwestern MO/northeastern KS where
dewpoints will be near 60 degrees, modest instability of 500-
800J/kg, and steep mid-level lapse rates will exist. However, shear
is not impressive and as previously mentioned instability is merely
modest. Consequently, strong storms will be possible and perhaps
even a marginally severe storm capable of producing large hail or
damaging winds. Storms will weaken Sunday night as storms move into
a more stable environment and the upper level trough continues to
weak as it moves into the Upper Midwest. On Monday, the cold front
associated with the upper level system will sag through the area.
However, will little forcing the front will sag through the area
with little activity expected. The best chance for storms would
occur head of the front where modest instability will reside. Monday
night the cold front will sink south of the area and become
stationary. A few thunderstorms may develop north of the stationary
boundary Monday as a SW 40kt LLJ overrides the boundary. These
thunderstorms may affect the southern CWA depending on the location
of the front.
.Long Term...(Tuesday through Saturday)
Issued at 309 PM CDT SAT APR 23 2016
Tuesday evening and Wednesday will bring another round of showers
and possibly severe thunderstorms to the CWA. The most recent NAM
and GFS runs show Tuesday morning and early afternoon warm and humid
with precipitation mainly staying just south of the WFO. A negatively
tilted low pressure trough stations itself over eastern CO/western KS
Tuesday afternoon. A cold front will move east through Kansas
Wednesday afternoon, and an associated warm front will be located E-W
through our forecast area late Tuesday bringing low- level moisture
with it. Dew point temperatures will range from low 50s north of the
front spreading south to the mid-60s. We will also have decent
instability and shear with CAPE values around 1000-2000 J/kg and
30-50 kt 0-6 km bulk shear. A combination of high CAPE and shear may
lead to potentially severe thunderstorms ahead of the cold front. The
development and location of severe weather will depend on the timing
of convection and the frontal passage, which will become more clear
as we get closer to the event. For now, the GFS and Euro models show
precipitation starting in eastern KS and moving east through the WFO
late Tuesday night through Wednesday morning. Convection could
continue throughout Wednesday as CAPE values are expected to stay
above 1000 J/kg throughout Wednesday afternoon.
High temperatures will continue to be in the mid 70s through
Wednesday, but will drop to the mid-high 60s for Thursday and Friday
after the cold front passes. Low temperatures will drop Thursday and
Friday mornings to the high 40s to low 50s. Thursday is expected to
be dry before another upper low system may cause more precipitation
late Friday into Saturday.
&&
.Aviation...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1230 PM CDT SAT APR 23 2016
VFR conds will prevail through the pd with mainly just sct high
clouds expected. Winds will pick up out of the south this afternoon
to 10-15kts with gusts to around 20kts. Winds will lose their gusts
this evening but still remain around 10-15kts. However, tomorrow
morning winds will again increase to 15-20kts with gusts to 25-30kts.
LLWS may be a marginal concern tonight as winds at 2kft will be out
of the SSW at 35-40kts btn 06Z-14Z and, may need to be added to the
TAF at the 00Z issuance.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Short Term...73
Long Term...Chandler/CDB
Aviation...73
Area Forecast Discussion
National Weather Service Saint Louis MO
257 PM CDT SAT APR 23 2016
.SHORT TERM... (Through Late Tonight)
Issued at 255 PM CDT Sat Apr 23 2016
Surface ridge extending from MI southwest into eastern MO will move
eastward. The stratus clouds across southeast IL should continue to
dissipate late this afternoon. Few-scattered diurnal cumulus
clouds, especially across parts of northeast and central MO will
dissipate early this evening with the loss of daytime heating.
Mainly just a little high level cloudiness tonight. Lows tonight
will be warmer than the previous night, mainly due to southeast
surface winds on the backside of the surface ridge. The warmest
temperatures will be across central MO with the coolest temperatures
in southwest IL. Lows tonight will be about 5 to 10 degrees above
normal for late April.
GKS
.LONG TERM... (Sunday through Next Saturday)
Issued at 255 PM CDT Sat Apr 23 2016
Dry and warmer weather to persist on Sunday, but will see an
increase in high clouds as next weather system approaches region.
With gusty south winds will see highs in the upper 70s to low 80s.
Sunday night rain chances to approach region, but models are a bit
slower with onset, so lowered pops just a bit. Then Monday through
Tuesday, frontal boundary to slowly slide south through area with
mainly scattered showers and thunderstorms. Front to stall out
across southern Missouri on Tuesday. Highs will be in the upper 70s
to low 80s on Monday, then dip down into the low 70s to low 80s
Tuesday and Wednesday.
Decent instability north of front Tuesday night, so could see
elevated activity develop and slide along boundary on nose of decent
low level jet. Large hail would be the main threat with this round
of storms.
Models are still indicating decent instability, CAPES in excess of
1500 J/kg and shear with system Wednesday afternoon, Wednesday night
as warm front lifts north through forecast area. All of this still
points to our first real potential severe weather day this spring,
but a lot can happen in 5 days. Stay tuned to further updates.
With everything a bit slower, main cold front to slide through early
on Thursday with precipitation tapering off to just slight chance
pops through Friday. Then extended models showing next system
lifting northeast towards forecast area Friday night and Saturday
with increasing chances of showers and thunderstorms once again.
Once system exits region on Thursday, will see precipitation taper
off. Even though it will be a bit cooler Thursday, highs will still
be a bit above normal in the mid 60s to upper 70s. Extended models
beginning to indicate another system approaching region on Friday,
but timing is hard to pin down. So for now kept slight chance pops.
Byrd
&&
.AVIATION... (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1104 AM CDT Sat Apr 23 2016
Surface ridge extending from the Great Lakes region southwest
into eastern MO will shift eastward this period. The low level
cloudiness over eastern IA into northeast MO should remain north
of UIN this afternoon. The stratus cloudiness across southeast IL
should gradually dissipate this afternoon with daytime heating,
mixing and drying and remain east of the St Louis metro area.
There may be a few diurnal cumulus clouds at the taf sites this
afternoon. There will be a little high level cloudiness late
tonight and Sunday morning. Southeasterly surface winds should
strengthen at UIN and COU through the forecast period as the
surface pressure gradient gradually tightens, becoming more
southerly on Sunday. Light northeast wind in the St Louis metro
area will also strengthen as well through the period, veering
around to a southeast direction by early this evening, then
southerly Sunday morning. There will be some LLWS conditions in
UIN and COU very late tonight and early Sunday morning as a
southwesterly low level jet translates eastward into northwest MO
with both speed and directional shear in the lowest 1000 feet.
Specifics for KSTL: Stratus clouds across southeast IL should
gradually dissipate this afternoon and remain east-southeast of
STL. Few diurnal cumulus clouds may develop this afternoon due to
daytime heating, then dissipate early this evening. There will be
some high level cloudiness late tonight and Sunday. Light
northeast wind will increase in speed to 8-10 kts by late this
afternoon or early this evening as it veers around to a southeast
direction. The surface wind will become southerly Sunday morning
and possibly gusty Sunday afternoon.
GKS
&&
.PRELIMINARY POINT TEMPS/POPS...
Saint Louis 55 82 63 81 / 0 0 20 30
Quincy 56 81 61 79 / 5 5 30 30
Columbia 57 81 60 78 / 5 5 20 30
Jefferson City 58 82 61 80 / 5 5 20 30
Salem 51 79 60 80 / 0 0 10 20
Farmington 52 79 60 79 / 0 0 10 20
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1230 PM CDT SAT APR 23 2016
.Discussion...
Issued at 412 AM CDT SAT APR 23 2016
Today - Tonight:
In the very near term will be dealing with patchy dense fog over the
northeast 1/2 of the CWA. The fog and stratus is forming under a
surface ridge with river valleys and low lying areas the most
susceptible. The latest NAM/RAP 925mb condensation pressure deficit
prog best depict the low clouds with the SREF favoring more
widespread dense fog further north in IA.
Otherwise, for today expect a nice warm up as pressure falls over
the Central Plains induce increasing southerly winds. Should see
decent mixing with a dry adiabatic lapse rate yielding highs around
10 degrees above average. Upper level ridging spreading east into
the CWA will provide for continued dry conditions.
Increasing warm air advection aloft will ensue across KS and NE this
evening with scattered elevated convection possibly grazing far
northwest MO towards sunrise Sunday morning. Any convection which
reaches this region should fall apart Sunday morning with convective
debris and mid level accas likely lingering over the western CWA
into the afternoon.
Sunday - Sunday night:
The weather will become more interesting late Sunday afternoon into
the evening as an upper level closed low migrates into SD/NE. A
negatively tilted shortwave trough is progged to rotate from under
the upper low and lift northeast across KS and NE during the
afternoon. A moderately strong low level jet around 45kts will pull
deeper low level moisture ahead of a north-south dryline which will
anchor over central KS and far western OK. Expect to see scattered
strong/severe convection form along the dryline by mid/late
afternoon and track quickly northeast. Far northwest MO stands the
best chance of seeing active convection. Surface based CAPEs around
1500 J/kg and 0-6km shear around 40kts will support
strong/marginally severe storms over this area. All models strongly
suggest the dryline will move little to the east so the severe
threat in the CWA will likely be limited to far northwest MO.
Convection will weaken and decrease in coverage as it moves east
through the CWA with the far southeastern counties receiving the
least QPF.
Monday - Friday:
A fairly active period with two more closed upper lows likely
affecting the region. While Monday initially looked relatively quiet
as the Upper MS Valley system pulls away there is some concern that
some afternoon convection could form along the remnants of a stalled
surface boundary. The limiting factor will be increasing mid level
heights and a lack of upper support. Nonetheless with a front in the
CWA will need to be vigilant.
As we`ve been discussing over the past few days a second and
stronger upper system will become a factor and play a significant
role in our weather by Tuesday night and continuing into Wednesday.
Medium range operational models continue to eject a negatively
tilted shortwave through KS and MO. There is every reason to believe
a west-east frontal boundary will be in the vicinity with this
feature lifting north and through the CWA. Low-level moisture will
not be a problem with low/mid 60 dewpoints likely south of the front
and spreading northward. The GFS indicates 2000-3000 J/kg of CAPE
could be available with 30-40kt 0-6km shear so severe storms are a
growing concern. As always timing of the front and convective
development will determine where severe will occur but our CWA is
currently within the window of opportunity.
Convection could linger well into Wednesday as the upper low opens
up and lifts through NE/KS/IA/MO.
Thursday looks quiet as we`ll be between systems. The third system
we`ll be keeping an eye on will be yet another closed upper low.
This feature may not be a factor until late Friday.
Through out this period expect to see above average temperatures with
an overall increase in humidity.
&&
.Aviation...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1230 PM CDT SAT APR 23 2016
VFR conds will prevail through the pd with mainly just sct high
clouds expected. Winds will pick up out of the south this afternoon
to 10-15kts with gusts to around 20kts. Winds will lose their gusts
this evening but still remain around 10-15kts. However, tomorrow
morning winds will again increase to 15-20kts with gusts to 25-30kts.
LLWS may be a marginal concern tonight as winds at 2kft will be out
of the SSW at 35-40kts btn 06Z-14Z and, may need to be added to the
TAF at the 00Z issuance.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...MJ
Aviation...73
Area Forecast Discussion
National Weather Service Springfield MO
1206 PM CDT SAT APR 23 2016
.SHORT TERM...(Today through Sunday)
Issued at 330 AM CDT Sat Apr 23 2016
An upper level ridge is currently building over the region early
this morning and will be centered over the area by tonight. As an
upper level trough tracks east into the northern Plains on Sunday
the ridge will start to spread off Sunday night.
Warm and dry conditions will occur through much of this weekend
as highs warm into the upper 70s to the lower 80s both afternoons.
Sunny skies will occur today with partly cloudy skies occurring on
Sunday. Gusty southerly winds will develop Sunday afternoon as
surface low pressure develops across the central Plains ahead of
the upper level low. Wind gusts over 30 mph can be expected for
locations generally along and west of Hwy 65 Sunday afternoon.
.LONG TERM...(Sunday night through Friday)
Issued at 330 AM CDT Sat Apr 23 2016
As the upper level low tracks east storms are expected to develop
to the west and northwest of the area along a cold front Sunday
evening. The front will then drop to the southeast into the area
Sunday night into Monday. The better lift and instability will
remain to the northwest and north of the area as the upper level
trough remains well north of the area. There will be an
instability gradient that sets up close to the far northwestern
portions of the area, so storms will be weakening as they move
southeast into the area, but a few strong storms may still be
possible generally northwest of a Pittsburg KS to Nevada MO line
Sunday night into early Monday morning. Coverage in storms will be
decreasing as the storms move into the area and will be isolated
to scattered in nature and many locations will remain dry. It is
also possible the storms dissipate just to the northwest of the
area.
As the front moves south through the area on Monday a few
thunderstorms will be possible, but overall most locations will
remain dry as coverage will be very limited with this activity.
Instability is expected to remain on the weak side, therefore,
not expecting a severe risk Monday.
Another upper level low will push into the northwestern U.S.
Sunday then dig to the south into the southwestern U.S. Monday
then lift to the northeast across the plains by Wednesday. As the
upper level low lifts to the northeast, the front that moves
south through the region Sunday night into Monday will lift back
to the north as a warm front Monday night into Tuesday morning.
Scattered storm chances will occur again along the front as it
lifts north.
Instability will then increase across the region on Tuesday ahead
of the approaching storm system, but a strong cap will also
develop across the area. The strong lift with this system will
remain well west of the area through the day on Tuesday, Therefore
most of the day should be dry after the warm front lifts north of
the area.
Storms are expected to develop across central Kansas
to the south into central Texas Tuesday evening along a cold
front. The front will then track east Tuesday night into Wednesday
Wednesday across the area. There is still some question on the
exact timing of the front but it will be at some point during the
day on Wednesday. There will be a severe risk with the storms
overnight Tuesday into Wednesday as the gulf moisture and an
unstable air mass will be in place across the area, large hail and
strong winds will be the main risk.
As the system moves off to the east mostly dry weather will occur
on Thursday. Then another system will begin to track into the
region Friday into the start of the weekend brining additional
chances for thunderstorms to the area.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1159 AM CDT Sat Apr 23 2016
VFR conditions are expected through the period as surface high
pressure continues to drift eastward and an upper level ridge
moves across the area. Main forecast concern is gusty winds
beginning after sunrise on Sunday as the next approaching system
begins to tighten up the surface pressure gradient. Winds should
develop gusts after 13z at KSGF/KJLN but believe that it will be
later in the afternoon...after the end of the forecast
period...for KBBG.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...Gaede
Area Forecast Discussion
National Weather Service Springfield MO
1206 PM CDT SAT APR 23 2016
.SHORT TERM...(Today through Sunday)
Issued at 330 AM CDT Sat Apr 23 2016
An upper level ridge is currently building over the region early
this morning and will be centered over the area by tonight. As an
upper level trough tracks east into the northern Plains on Sunday
the ridge will start to spread off Sunday night.
Warm and dry conditions will occur through much of this weekend
as highs warm into the upper 70s to the lower 80s both afternoons.
Sunny skies will occur today with partly cloudy skies occurring on
Sunday. Gusty southerly winds will develop Sunday afternoon as
surface low pressure develops across the central Plains ahead of
the upper level low. Wind gusts over 30 mph can be expected for
locations generally along and west of Hwy 65 Sunday afternoon.
.LONG TERM...(Sunday night through Friday)
Issued at 330 AM CDT Sat Apr 23 2016
As the upper level low tracks east storms are expected to develop
to the west and northwest of the area along a cold front Sunday
evening. The front will then drop to the southeast into the area
Sunday night into Monday. The better lift and instability will
remain to the northwest and north of the area as the upper level
trough remains well north of the area. There will be an
instability gradient that sets up close to the far northwestern
portions of the area, so storms will be weakening as they move
southeast into the area, but a few strong storms may still be
possible generally northwest of a Pittsburg KS to Nevada MO line
Sunday night into early Monday morning. Coverage in storms will be
decreasing as the storms move into the area and will be isolated
to scattered in nature and many locations will remain dry. It is
also possible the storms dissipate just to the northwest of the
area.
As the front moves south through the area on Monday a few
thunderstorms will be possible, but overall most locations will
remain dry as coverage will be very limited with this activity.
Instability is expected to remain on the weak side, therefore,
not expecting a severe risk Monday.
Another upper level low will push into the northwestern U.S.
Sunday then dig to the south into the southwestern U.S. Monday
then lift to the northeast across the plains by Wednesday. As the
upper level low lifts to the northeast, the front that moves
south through the region Sunday night into Monday will lift back
to the north as a warm front Monday night into Tuesday morning.
Scattered storm chances will occur again along the front as it
lifts north.
Instability will then increase across the region on Tuesday ahead
of the approaching storm system, but a strong cap will also
develop across the area. The strong lift with this system will
remain well west of the area through the day on Tuesday, Therefore
most of the day should be dry after the warm front lifts north of
the area.
Storms are expected to develop across central Kansas
to the south into central Texas Tuesday evening along a cold
front. The front will then track east Tuesday night into Wednesday
Wednesday across the area. There is still some question on the
exact timing of the front but it will be at some point during the
day on Wednesday. There will be a severe risk with the storms
overnight Tuesday into Wednesday as the gulf moisture and an
unstable air mass will be in place across the area, large hail and
strong winds will be the main risk.
As the system moves off to the east mostly dry weather will occur
on Thursday. Then another system will begin to track into the
region Friday into the start of the weekend brining additional
chances for thunderstorms to the area.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1159 AM CDT Sat Apr 23 2016
VFR conditions are expected through the period as surface high
pressure continues to drift eastward and an upper level ridge
moves across the area. Main forecast concern is gusty winds
beginning after sunrise on Sunday as the next approaching system
begins to tighten up the surface pressure gradient. Winds should
develop gusts after 13z at KSGF/KJLN but believe that it will be
later in the afternoon...after the end of the forecast
period...for KBBG.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...Gaede
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1140 AM CDT SAT APR 23 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 350 AM CDT Sat Apr 23 2016
Focus today will be clouds and temps.
Sfc ridge will continue to drift ewd today, allowing sly winds to
return to wrn portions of the CWA. Winds elsewhere are expected to
remain sely to ely.
The area of clouds currently just E of the CWA shud remain E.
However, some clouds may drift into ern portions of the CWA mainly
this morning until the ridge pushes them out of the area.
A secondary ridge axis over nrn portions of the CWA is expected to
be the focus for FG/stratus this morning. There is still uncertainty
regarding how widespread any FG will be, as well as any stratus. The
additional moisture within the bndy layer across this region shud
allow for at least sct clouds this morning, dissipating thru the
afternoon.
All of this leads to a rather complex temp forecast for today. For
ern portions of the CWA, have kept temps cooler where the ridge axis
will remain in place longer. Areas under this ridge yesterday saw
temps in the upper 60s, however, believe there will be less cloud
cover today. Believe the warmer temps will build into wrn portions
of the CWA where winds will become sly as well as the thermal ridge
building into this area. Have gone with trends close to a blend of
the RAP and local 4km WRF, which has been a good mix in these
setups. Did trend slightly cooler than this blend across nrn
portions of the CWA where more questions exist regarding cloud cover
today.
Tilly
.LONG TERM... (Tonight through Friday)
Issued at 350 AM CDT Sat Apr 23 2016
An upper level longwave RIDGE axis will persist over the Plains
thru much of next week, with upper longwave TROFs on the west and
east coasts. A series of strong Pacific storms will run thru this
RIDGE, being dropped off from the west coast TROF and being picked
up by the east coast TROF a few days later, with an overall track to
the E-NE thru our region. It would seem that each successive storm
system will track a bit further south than its predecessor.
The first storm system is slated to track to our north late Sunday
and into Monday, and will be mostly a glancing blow to our region as
a result, with what forms mostly upstream initially to our northwest
as it is thrown in our direction and largely weakens as it moves in.
This convection may also create additional boundaries during Monday
afternoon and early evening to maintain the threat for showers and
thunderstorms.
In the wake of this first storm system, a cold front will drop down
late Monday night into Tuesday and will maintain a low chance for
rain.
The second Pacific storm system will be more of a direct hit as it
will initially correspond well with the surface frontal boundary
buckling north as a warm front Wednesday morning. This should
result in elevated storms with hail as their primary threat during
that time.
Heading into Wednesday afternoon and evening, it will depend heavily
on how far north the front gets. Models have been trending with
less northward progress from 24hrs ago, but anywhere to the south of
it will have plenty of instability and moisture as well as strong
shear for more surface-based storms which will have a good potential
for some severe.
The rain potential lingers into Thursday if the cold front slows
enough to not make it thru until this day.
Friday should be a dry day, finally, but it appears only briefly
until yet another storm system approaches from the west in time for
the following weekend.
Otherwise, the longwave RIDGE setup will ensure that temps remain at
or above average throughout the period.
TES
&&
.AVIATION... (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1104 AM CDT Sat Apr 23 2016
Surface ridge extending from the Great Lakes region southwest
into eastern MO will shift eastward this period. The low level
cloudiness over eastern IA into northeast MO should remain north
of UIN this afternoon. The stratus cloudiness across southeast IL
should gradually dissipate this afternoon with daytime heating,
mixing and drying and remain east of the St Louis metro area.
There may be a few diurnal cumulus clouds at the taf sites this
afternoon. There will be a little high level cloudiness late
tonight and Sunday morning. Southeasterly surface winds should
strengthen at UIN and COU through the forecast period as the
surface pressure gradient gradually tightens, becoming more
southerly on Sunday. Light northeast wind in the St Louis metro
area will also strengthen as well through the period, veering
around to a southeast direction by early this evening, then
southerly Sunday morning. There will be some LLWS conditions in
UIN and COU very late tonight and early Sunday morning as a
southwesterly low level jet translates eastward into northwest MO
with both speed and directional shear in the lowest 1000 feet.
Specifics for KSTL: Stratus clouds across southeast IL should
gradually dissipate this afternoon and remain east-southeast of
STL. Few diurnal cumulus clouds may develop this afternoon due to
daytime heating, then dissipate early this evening. There will be
some high level cloudiness late tonight and Sunday. Light
northeast wind will increase in speed to 8-10 kts by late this
afternoon or early this evening as it veers around to a southeast
direction. The surface wind will become southerly Sunday morning
and possibly gusty Sunday afternoon.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
711 PM CDT SAT APR 23 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 345 PM CDT SAT APR 23 2016
ALOFT: A RIDGE WAS OVER THE PLAINS IN ADVANCE OF AN UPR LOW AND
ASSOCIATED TROF OVER THE WRN USA. THIS LOW WAS OVER UT AND THE GFS
ENSEMBLE MEMBERS AND LATEST 2 RUNS OF NAM/GFS/EC/GEM ARE TIGHTLY
CLUSTERED ON IT MOVING INTO WY BY 00Z...CROSSING THE STATE TONIGHT
AND THEN INTO SW SD TOMORROW.
SURFACE: LOW PRES WAS OVER SE MT WITH A WARM FRONT EXTENDING E
THRU SD AND THEN SE INTO THE MID MS VALLEY. A PAC COLD FRONT
EXTENDED SW THRU WY/UT/AZ...WITH A LEE TROF EXTENDING S THRU
WY/CO/NM. THE LOW WILL GRADUALLY EJECT INTO SD THIS EVE AND
ESSENTIALLY STALL... AWAITING THE ARRIVAL OF THE UPR LOW. THE COLD
FRONT WILL WEAKEN AND MERGE WITH THE LEE TROF TONIGHT BEFORE
ADVANCING THRU THE FCST AREA TOMORROW. MEANWHILE...A SURGE OF E-W
ORIENTED CANADIAN AIR WILL DROP S AND BEGIN SURGING AROUND THE
BACKSIDE OF THE LOW AS A COLD FRONT TOMORROW AFTERNOON. THIS FRONT
WILL BE APPROACHING THE NW FRINGE OF THE FCST AREA BY 00Z/MON.
REST OF THIS AFTERNOON: INCREASING THICK CIRROSTRATUS FROM THE W.
WINDY AS S WINDS CONT TO GUST 30-40 KTS.
PEAK GUST THUS FAR 39 KTS AT EAR.
TONIGHT: M/CLOUDY AND MILD. STILL WINDY...ESPECIALLY PRIOR TO 3
AM WITH S WINDS GUSTING UP TO 35 KTS. THEN WINDS DIMINISH AS THE
SFC TROF APPROACHES.
HIGH-BASED TSTMS WILL DEVELOP OVER THE HIGH PLAINS TO THE SW THIS
AFTERNOON/EVE AND SPREAD NE INTO THE FCST AREA...MOST LIKELY
SUSTAINED BY THE COLD FRONT ALOFT. TEMPS CLOSE TO 80F AND DWPTS
NEAR 50F HAVE RESULTED IN A NARROW AXIS OF MUCAPE OF 1000-1500
J/KG TO THE W THIS AFTERNOON. DIURNAL COOLING WILL REDUCE THIS
INSTABILITY LEAVING 500-750 J/KG. ENOUGH FOR PROBABLY SOME SMALL
HAIL AND G40 KTS IN A COUPLE SPOTS.
SUN: DECREASING CLOUDS FROM W-E. THE COLD FRONT ALOFT WILL BE
MOVING THRU THE E HALF OF THE FCST AREA IN THE AFTERNOON. THERE IS
A NARROW WINDOW OF OPPORTUNITY FOR THE FIRST STORMS OF THE DAY TO
FIRE E OF HWY 281 AND THEY COULD BE SVR.
SVR: DRIER SFC AIR WILL HAVE OVERTAKEN MOST OF THE FCST AREA
BEHIND THE SFC TROF...BUT DWPTS COULD STILL 58-62F E OF HWY 281.
AND WITH TEMPS IN THE MID 70S...THIS WILL RESULT IN MLCAPE UP TO
1500 J/KG. THE WIND PROFILE WILL BE UNIDIRECTIONAL...BUT WITH
DEEP LAYER SHEAR AROUND 40 KTS. THAT IS STRONG ENOUGH FOR A
SUPERCELL CONVECTIVE MODE BEFORE STORMS CONSOLIDATE INTO A LINE
WHICH WILL PROBABLY HAPPEN OVER ERN NEB.
CELL MOVEMENT WILL BE FROM THE SW AT 45 KTS.
THE COLD FRONT WILL BE APPROACHING FROM THE NW LATE AFTERNOON...
BUT ANY INSTABILITY SHWR ACTIVITY WITH THE UPR LOW BEHIND IT IN
THE COLD AIR.
ANOTHER VERY WARM DAY TOMORROW. BUMPED UP HIGHS FROM THE PRVS FCST
TO 75-82F...COOLEST N AND W OF THE TRI-CITIES.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 345 PM CDT SAT APR 23 2016
A PERSISTENT LONGWAVE TROUGH IN THE WESTERN UNITED STATES WILL
CONTINUE TO EJECT ENERGY INTO THE CENTRAL PLAINS...KEEPING THE
POTENTIAL OF THUNDERSTORMS IN THE FORECAST FOR MUCH OF THE LONG
TERM. THIS WILL BE AN ACTIVE WEATHER PATTERN AND THERE IS
PARTICULAR INTEREST IN SEVERE WEATHER CHANCES TUESDAY AFTERNOON
AND EVENING.
A NEGATIVELY TILTED MID TO UPPER LEVEL SHORTWAVE TROUGH WILL
CONTINUE ITS TREK THROUGH THE NORTHERN/CENTRAL PLAINS SUNDAY
EVENING WITH A CLOSED LOW MOVING ACROSS NORTHERN NEBRASKA AND
SOUTH DAKOTA. THE ASSOCIATED SURFACE COLD FRONT SHOULD CLEAR THE
CWA BY MID- EVENING. OUR FAR EAST MAY HAVE SOME LINGERING
PRECIP/SEVERE CHANCES...DEPENDING ON HOW FAST THE COLD FRONT MAKES
IT THROUGH. SEVERE WEATHER WILL LIKELY BE EAST OF THE CWA...ALONG
A DRY LINE.
A STRONGER WAVE DROPS INTO THE INTERMOUNTAIN WEST MONDAY AS A
LOW- AMPLITUDE NEGATIVELY TILED SHORTWAVE RIDGE TRAVERSES THE
CENTRAL PLAINS FROM SOUTHWEST TO NORTHEAST...ALL BUT INSURING A
DRY PERIOD. AS A LOW-LEVEL JET MOVES IN FROM THE WEST...WE COULD
GET SOME THUNDERSTORM ACTIVITY MONDAY NIGHT...FOCUSED MORE WEST
SOUTHWEST...CLOSER TO THE THETA-E AXIS.
ON TUESDAY THERE SEEMS TO BE GOOD AGREEMENT AMONG BOTH THE
OPERATIONAL RUNS AND ENSEMBLES THAT WE WILL HAVE THE STRONG
NEGATIVELY TILTED WAVE MOVE OUT INTO THE CENTRAL PLAINS TUESDAY
AFTERNOON/EVENING. I AM MOST CONCERNED ABOUT A WARM FRONT ACROSS
NORTHERN KANSAS THAT COULD BE THE FOCUS OF SEVERE WEATHER...
INCLUDING TORNADOES. MOISTURE TRANSPORT INCREASES ACROSS THE WARM
SECTOR AND MODERATE TO STRONG INSTABILITY WILL BE IN PLACE.
VERTICAL WIND PROFILES INDICATE SIGNIFICANT SPEED AND DIRECTIONAL
SHEAR AND LOW/MID LEVEL LAPSE RATES HAVE THE POTENTIAL TO BE
STEEP. AS THE WAVE MOVES INTO THE PLAINS...HEIGHT FALLS WILL
ENCOURAGE THUNDERSTORM DEVELOPMENT...AND WILL LIKELY HAVE SEVERE
WEATHER DEVELOP AS A RESULT...ESPECIALLY IN OUR SOUTH NEAR WHERE
THE WARM/STATIONARY FRONT IS EXPECTED TO BE. THIS WAVE LOOKS LIKE
IT MEANS BUSINESS. THERE IS ALSO A GOOD CHANCE OF QUITE A BIT OF
NOCTURNAL CONVECTION TUESDAY NIGHT AS THE TROUGH AXIS CROSSES THE
CWA.
FOR WEDNESDAY...WE COULD CONTINUE TO GET CONVECTION...ESPECIALLY
NORTH AS THE AS THE CLOSED LOW MOVES NORTHEAST AND THE ELONGATED
TROUGH PIVOTS...KEEPING THE AXIS CLOSE BY TO THE NORTH. THE SEVERE
THREAT SHIFTS EAST AS THE CLOSED UPPER LOW AND SURFACE LOW/COLD
FRONT WILL BE FAR ENOUGH EAST TO QUELL SEVERE WEATHER CONCERNS.
ANOTHER SHORTWAVE RIDGE FOR THURSDAY SHOULD HELP KEEP THIS DAY
DRY...BUT ANOTHER WAVE WILL BE ON ITS WAY AND THURSDAY NIGHT A
LOW-LEVEL JET WILL DEVELOP THAT WILL ONCE AGAIN PUT THUNDERSTORMS
BACK IN THE FORECAST.
THE TROUGH TAKES ITS TIME SWINGING THROUGH AS IT BECOMES MORE
NEGATIVELY TILED AND A CLOSED LOW DEVELOPS OVER THE WEEKEND. THE
FRIDAY AFTERNOON THROUGH SATURDAY NIGHT TIME FRAME COULD BE
ANOTHER POTENTIAL FOR MORE SEVERE WEATHER...BUT IT IS STILL A
LITTLE EARLY TO DO MUCH MORE SPECULATION.
TEMPERATURES WILL BE WITHIN A TYPICAL RANGE FOR THE LONG TERM...
BUT THE HIGHS MAY WIND UP BEING AVERAGE TO A BIT BELOW AVERAGE AND
LOWS NEAR TO A BIT ABOVE AVERAGE GENERALLY INCREASED SKY
COVER/MOISTURE. THIS WORKS OUT TO BE HIGHS MOSTLY IN THE LOWER TO
MID 60S AND LOWS IN THE 40S.
&&
.AVIATION...(FOR THE 00Z KGRI/KEAR TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 707 PM CDT SAT APR 23 2016
IT IS A CHALLENGING FORECAST WITH SOME MODELS LIKE THE RUC
INDICATING STRONG LOW LEVEL WIND SHEAR...WHILE THE NAM IS LESS
SEVERE WITH THE WIND SHEAR AND WOULD NOT EVEN BE WORTH MENTIONING
IN THE TAF. WILL CONTINUE TO GO WITH AT LEAST THE POTENTIAL FOR
STRONG LOW LEVEL WIND SHEAR SINCE IT WAS ALREADY IN THE
FORECAST...BUT CONFIDENCE IS LOWER THAN NORMAL. WE ALSO HAVE THE
18Z NAM...SEVERAL WRF MODELS...AND THE 12Z ECMWF BASICALLY
CALLING FOR A DRY NIGHT...WHILE THE HRRR AND THE 18Z GFS HINT AT
THUNDERSTORMS LATER TONIGHT. MOST LIKELY WE WILL BE DRY OR SEE
VERY LITTLE IF ANY PRECIPITATION...BUT WILL KEEP THE VICINITY
THUNDER IN THE TAF FOR NOW.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...HALBLAUB
LONG TERM...HEINLEIN
AVIATION...WESELY
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1119 PM CDT THU APR 21 2016
.SYNOPSIS...
ISSUED AT 333 PM CDT THU APR 21 2016
H5 ANALYSIS FROM EARLIER THIS MORNING HAD A CLOSED LOW
OVER WESTERN IOWA WITH A TROUGH OF LOW PRESSURE EXTENDING SOUTH INTO
THE ARKLATEX. HT FALLS OF 50 TO 70 METERS WERE NOTED FROM THE MID
MISSISSIPPI VALLEY NORTHWARD TO THE ARROWHEAD OF MINNESOTA. WEST OF
THE TROUGH AND CLOSED LOW...WAS A RIDGE OF HIGH PRESSURE WHICH
EXTENDED FROM THE FOUR CORNERS...NORTH TO NORTHERN MONTANA. WEST OF
THE RIDGE...A TROUGH OF LOW PRESSURE WAS PRESENT FROM THE
ALEUTIANS...SOUTH INTO THE EASTERN PACIFIC...AND WAS ROUGHLY 500
MILES WEST OF THE OREGON AND WASHINGTON COASTS. AT THE SURFACE...LOW
PRESSURE WAS LOCATED OVER CENTRAL IOWA WITH HIGH PRESSURE ANCHORED
ACROSS THE FRONT RANGE OF COLORADO AND WYOMING. ACROSS WESTERN AND
NORTH CENTRAL NEBRASKA...WINDS WERE NORTHERLY BETWEEN THESE TWO
SURFACE FEATURES...AND WERE BREEZY THIS AFTERNOON WITH SPEEDS OF 15
TO 25 MPH. UNDER PARTLY CLOUDY SKIES...TEMPERATURES WERE IN THE
UPPER 60S TO AROUND 70.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 333 PM CDT THU APR 21 2016
MAIN FORECAST CONCERNS ARE WIND AND TEMPERATURES. THE UPPER LOW
CONTINUES ITS SLOW EASTWARD TREK AND GETS ABSORBED WITH THE OVERALL
FLOW OVER THE GREAT LAKES. H5 RIDGE BUILDS OVER THE GREAT PLAINS
WHILE A SURFACE TROUGH APPROACHES THE PANHANDLE LATE FRIDAY.
THIS EVENING AND TONIGHT... EFFICIENT MIXING TO NEAR 750HPA AS
INDICATED BY RAP AND HRRR SOUNDINGS AND NEARLY UNIDIRECTIONAL FLOW
CREATING GUSTS TO 25MPH FOR MUCH OF THE AREA. SOUNDINGS ALSO
INDICATE LOW LEVEL LIFT... WHICH IS CONFIRMED BY A GROWING CUMULUS
FIELD OVER WESTERN NEBRASKA. LEFT PRECIP MENTION OUT AS ABUNDANT DRY
AIR EXISTS IN THE MID LEVELS AND SURFACE DEW POINT DEPRESSIONS REACH
30F WEST TO 20F EAST. CLOUDS WILL CLEAR TONIGHT WITH THE LOSS OF
DIURNAL HEATING AND WINDS RELAX WITH BOUNDARY LAYER DECOUPLING.
MADE LITTLE CHANGE TO MIN TEMPS AS MID/UPPER 30S SEEMED REASONABLE
GIVEN CLEAR SKIES... LIGHT WINDS... AND NEGLIGIBLE TEMP ADVECTION AT
H85.
FRIDAY... CONTINUED THE TREND OF FOLLOWING WARMER GUIDANCE OR GOING
SLIGHTLY ABOVE FOR MAX TEMPS. RETURN FLOW SWITCHES LOW LEVEL WINDS
TO SOUTHERLY... AND MODELS IN AGREEMENT WITH APPRECIABLE WAA. H85
TEMPS RANGE FROM NEAR 20C PANHANDLE TO 10C NORTH CENTRAL... ABOUT 5
TO 10C WARMER THAN THURSDAY. LOW LEVEL WINDS STRENGTHEN THROUGHOUT
THE DAY AS THE PRESSURE GRADIENT INCREASES AHEAD OF THE TROUGH. NAM
SHOWING AROUND 1MB/HR FALLS DURING THE AFTERNOON. COUPLED WITH
SUBSIDENCE AND MIXING TO NEAR 800HPA WHERE H85 WINDS APPROACH
30KTS... GUSTS MAY REACH 25 TO 30MPH AT THE SURFACE. DESPITE WARM
TEMPERATURES AND BREEZY WINDS... FIRE WEATHER DOES NOT APPEAR TO BE
A SIGNIFICANT ISSUE AT THIS TIME. NAM...GFS...AND EURO KEEP SFC DEW
POINTS IN THE 40S DURING THE AFTERNOON... AND MIXING RATIOS INCREASE
1-2G/KG SINCE THURSDAY. MINIMUM RH VALUES STAY ABOVE 25 PERCENT
PANHANDLE AND 30 PERCENT EAST.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 333 PM CDT THU APR 21 2016
MID RANGE...FRIDAY NIGHT THROUGH SUNDAY...A TROUGH OF
LOW PRESSURE ALOFT WILL COME ONSHORE ACROSS NRN CALIFORNIA/OREGON
LATE FRIDAY. THIS FEATURE WILL TRACK EAST INTO WYOMING OVER THE NEXT
24 HOURS...MAKING IT AS FAR EAST AS NWRN WYOMING BY 00Z SUNDAY.
DURING THIS PERIOD...A STRONG LEE SIDE SFC CYCLONE WILL DEVELOP OVER
EASTERN WYOMING AND NERN COLORADO. EAST OF THIS FEATURE...SRLY WINDS
WILL INCREASE FRIDAY AFTERNOON INTO FRIDAY NIGHT. SRLY FLOW WILL
PUSH LOW LEVEL MOISTURE NWD DURING THE NIGHT AND THIS COUPLED WITH
THE SRLY WINDS...WILL MAKE FOR MILD TEMPS FRIDAY NIGHT. FCST LOWS
WILL BE IN THE UPPER 40S TO AROUND 50...SOME 10 TO 15 DEGREES ABOVE
NORMAL. ON SATURDAY...STRONG LOW LEVEL WARM AIR ADVECTION WILL
CONTINUE WITH H85 TEMPS REACHING 25C IN THE WEST BY 00Z SUN. THE
LATEST GUIDANCE REFLECTED THESE WARMER TEMPS SHOWN IN THE GRAPHICAL
NAM AND GFS FCST MODELS FROM THIS MORNING...AND HAVE TRENDED UP
HIGHS FOR SAT AFTN. THIS RESULTED IN HIGHS IN THE LOWER 80S ACROSS
THE BOARD. WE EVEN MAY SEE SOME MIDDLE 80S IN THE NORTHWEST WHERE
DRIER AIR IS EXPECTED SAT AFTN. ON SATURDAY EVENING...A PACIFIC COLD
FRONT WILL APPROACH THE PANHANDLE SAT EVENING...AND A LEAD
DISTURBANCE WILL APPROACH SWRN NEBRASKA FROM NERN COLORADO.
THUNDERSTORM CHANCES WILL INCREASE DURING THE EVENING HOURS WITH THE
BEST CHANCES IN THE SOUTHWEST IN PROXIMITY TO THE UPPER LEVEL
WAVE...AND IN THE NORTHWESTERN CWA INVOF THE FRONT AND CLOSER
PROXIMITY TO THE H5 LOW. AS FOR THE THREAT FOR SEVERE STORMS...WAS
CONCERNED SOMEWHAT ABOUT THE 2000 J/KG CAPES DEPICTED IN THE 12Z
NAM SOLN THIS MORNING...ACROSS CENTRAL PORTIONS OF THE CWA.
HOWEVER...BULK SHEAR IS ONLY 15 TO 20 KTS SAT AFTN/EVE...SO THE
SEVERE THREAT APPEARS MINIMAL ATTM. ON SUNDAY...THE UPPER LEVEL LOW
WILL TRACK ALONG THE NEBR/SD BORDER. ATTM...THE MAIN THREAT FOR PCPN
WILL CONTINUE OVER NRN NEBRASKA WITH MAINLY DRY CONDS IN THE SOUTH.
IT WILL BE WINDY WITH DECENT NORTHWESTERLY WINDS BEHIND THE COLD
FRONT SUNDAY. TEMPERATURES WILL RANGE FROM AROUND 60 IN THE WEST TO
THE MID 70S IN THE FAR EAST.
LONG RANGE...SUNDAY NIGHT THROUGH THURSDAY...AN ACTIVE SWRLY FLOW
PATTERN WILL CONTINUE INTO NEXT WEEK. THE FIRST OF TWO UPPER LEVEL
LOWS WILL APPROACH THE FORECAST AREA MONDAY NIGHT WITH LIKELY PCPN
EXPECTED FOR TUESDAY INTO TUESDAY NIGHT. PCPN WILL LINGER IN THE
NORTH FOR WEDNESDAY...WITH DRY CONDS EXPECTED WEDS NIGHT INTO
THURSDAY. A SECOND SYSTEM WILL APPROACH THE REGION LATE THURSDAY
WITH ANOTHER ROUND OF PCPN ON TAP FOR FRIDAY INTO SATURDAY NEXT
WEEK. TEMPERATURES WILL BE COOL WITH HIGHS IN THE 50S WITH SOME 40S
POSSIBLE IN NRN NEBRASKA TUES/WEDS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1119 PM CDT THU APR 21 2016
VFR IS EXPECTED ALL AREAS OVERNIGHT THROUGH FRIDAY EVENING.
SFC LOW PRESSURE WILL ORGANIZE ACROSS THE NRN HIGH PLAINS BENEATH
AN UPPER LEVEL RIDGE OF HIGH PRESSURE. SKIES SHOULD REMAIN MOSTLY
CLEAR.
&&
.HYDROLOGY...
ISSUED AT 333 PM CDT THU APR 21 2016
RISES ON THE SOUTH PLATTE RIVER EXPECTED TO CONTINUE
OVER THE NEXT SEVERAL DAYS. UPSTREAM GAUGE AT JULESBURG STILL
SHOWING A SLOW RISE WITH AN EXPECTED CREST AT ROSCOE OF AROUND 7.3
FEET LATE FRIDAY/EARLY SATURDAY. ISSUED RVS THIS MORNING WITH
UPDATED FORECAST FROM MBRFC. SLIGHT UPTICK OBSERVED AT NORTH PLATTE
BUT STILL 1.5 FEET BELOW ACTION STAGE.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BUTTLER
SHORT TERM...SNIVELY
LONG TERM...BUTTLER
AVIATION...CDC
HYDROLOGY...SNIVELY
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
305 PM PDT FRI APR 22 2016
.SYNOPSIS...A SERIES OF PACIFIC STORM SYSTEMS WILL BRING COOLER
TEMPERATURES, WINDY PERIODS, AND CHANCES OF PRECIPITATION TO
PORTIONS OF THE REGION THROUGH EARLY NEXT WEEK. THE
BEST CHANCES OF PRECIPITATION APPEAR TO BE IN THE SIERRA AND
SOUTHERN GREAT BASIN TONIGHT THEN AGAIN ON MONDAY.
&&
.SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT.
THE VIGOROUS TROUGH DIVING OVER NORTHERN AND CENTRAL CALIFORNIA
WILL CONTINUE TO PRODUCE WIDESPREAD SOUTH-SOUTHWEST WINDS GUSTING
OVER 40 MPH ACROSS MUCH OF THE FORECAST AREA THIS EVENING. THE TROUGH
AXIS IS FORECAST TO QUICKLY TRAVERSE SOUTHERN NEVADA BETWEEN 06Z AND
12Z SATURDAY MORNING AND WE WILL LIKELY SEE SOME OF THE STRONGEST
GUSTS ACROSS SOUTHERN NEVADA AND THE MOJAVE DESERT REGION BETWEEN
05Z AND 09Z. SEVERAL SENSORS ACROSS THE NEVADA NATIONAL SECURITY SITE
IN NORTHERN NYE COUNTY RECORDED GUSTS OVER 60 MPH THIS AFTERNOON AND
A HIGH WIND WARNING WAS ISSUED FOR CENTRAL/SOUTHERN NYE AND WESTERN
LINCOLN COUNTIES AS SIMILAR GUSTS WILL CONTINUE INTO EARLY THIS EVENING.
THE LATEST HIGH RES MODELS INDICATE A FAIRLY QUICK DROP IN WIND SPEEDS
AFTER 04Z ACROSS INYO COUNTY AND SOUTH CENTRAL NEVADA THEN DECREASING
AFTER 10Z FOR THE SPRING MOUNTAINS AND MUCH OF THE MOJAVE DESERT ZONES.
NUMEROUS SHOWERS WILL OCCUR ACROSS NORTHERN INYO AND ESMERALDA COUNTIES
THIS EVENING AND POPS WERE INCREASED CONSIDERABLE FOR THOSE ZONES.
SATURDAY SHOULD BE A FAIRLY PLEASANT DAY WITH NORTHWEST WINDS GENERALLY
LESS THAN 15 MPH AND TEMPERATURES RUNNING ABOUT 10-12 DEGREES COOLER
ACROSS SOUTHERN NEVADA AND SURROUNDING AREAS. ATTENTION THEN TURNS TO
THE NEXT PACIFIC SYSTEM WHICH WILL BE NEAR THE PACIFIC NORTHWEST SUNDAY
MORNING THEN DIVING TOWARD SOUTHERN NEVADA SUNDAY NIGHT. THIS WILL BRING
INCREASING SOUTH-SOUTHWEST WINDS AHEAD OF IT SUNDAY AFTERNOON AND EVENING
AND THE POTENTIAL FOR SHOWERS WILL SPREAD DOWN ACROSS INYO COUNTY AND
SOUTH CENTRAL NEVADA INTO THE SPRING MOUNTAINS AND SHEEP RANGE SUNDAY
NIGHT.
.LONG TERM...MONDAY THROUGH THURSDAY.
ACTIVE PATTERN CONTINUES WITH TWO MORE STORMS IN THE LONG TERM
PERIOD. THE FIRST WILL BE AFFECTING OUR AREA MONDAY. MODELS ARE
CURRENTLY IN GOOD AGREEMENT...AND IF THE SOLUTIONS PAN OUT...PRECIP
CHANCES WOULD BE ROUGHLY FROM LAS VEGAS NORTH WITH STRONG WESTERLY
WINDS FROM LAS VEGAS SOUTH. JUDGING FROM THE CURRENT MODELS...WIND
ADVISORIES WOULD LIKELY BE NEEDED AGAIN FOR MUCH OF THE MOJAVE
DESERT...BUT WILL CONTINUE TO MONITOR FOR ANY NORTHWARD OR SOUTHWARD
SHIFTS IN THE STORM TRACK. SINCE THE STORM IS TRACKING EASTWARD
RATHER THAN SOUTHWARD...POST FRONTAL NORTHERLY WINDS TUESDAY SHOULD
NOT BE SIGNIFICANT. BY WEDNESDAY THE NEXT STORM APPROACHES THE WEST
COAST WITH SOUTHWEST WINDS INCREASING AGAIN.
THERE IS MORE MODEL SPREAD WITH THE TRACK AND STRENGTH OF THIS
STORM...AS IS TYPICAL 6-7 DAYS OUT. A MODEL CONSENSUS WOULD SUGGEST
A SIMILAR OUTCOME TO THE MONDAY STORM...EXCEPT PERHAPS SLIGHTLY LESS
STRONG WIND. PLENTY OF TIME TO WATCH THIS...WITH THE MAIN MESSAGE AT
THIS TIME BEING TO PREPARE FOR WINDY AND RAPIDLY CHANGING WEATHER
FOR MUCH OF NEXT WEEK. SPEAKING OF RAPIDLY CHANGING...TEMPERATURES
WILL CRASH DOWN TO ABOUT TEN DEGREES BELOW NORMAL AREAWIDE ON MONDAY
AND TUESDAY...RISE A BIT WEDNESDAY...THEN GET KNOCKED DOWN AGAIN ON
THURSDAY AS THE NEXT STORM ARRIVES.
&&
.AVIATION...FOR MCCARRAN...WINDY EVENING IN STORE FOR THE TERMINAL
AS A STORM SYSTEM MOVES THROUGH THE AREA TONIGHT AND TOMORROW. SOUTH
WINDS HAVE INCREASED THIS AFTERNOON AND SPEEDS/GUSTS SHOULD CONTINUE
TO CLIMB GRADUALLY THROUGH THIS EVENING AS DIRECTIONS VERY SLOWLY TO
A MORE SOUTHWESTERLY DIRECTION OVERNIGHT. MAX SPEEDS EXPECTED TO BE
20-30 KTS WITH GUSTS UP TO 40 KTS BETWEEN ABOUT 03Z AND 09Z. WINDS
WILL CONTINUE TO VEER AS A COLD FRONT APPROACHES THE VALLEY LATE
TONIGHT...BUT SPEEDS WILL DECREASE RAPIDLY AFTER 09Z. WINDS WILL
SWITCH TO N OR NW IN THE 12Z TO 16Z PERIOD. ALTHOUGH WINDS MAY PICK
UP DURING AND JUST AFTER FRONTAL PASSAGE...MOST GUIDANCE SUGGESTS
SPEEDS 5-15 KTS WITH AN OCCASIONAL GUST TO 20 KTS TOMORROW WITH THE
STRONGEST WINDS IN THE MORNING. FEW-SCT MID AND HIGH CLOUDS EXPECTED
THROUGH THE PERIOD. MECHANICAL TURBULENCE CAN BE EXPECTED THROUGH
TONIGHT ESPECIALLY DOWNSTREAM OF THE SPRING MOUNTAINS.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...SOUTH/SOUTHWEST WINDS HAVE INCREASED ACROSS THE AREA
THIS AFTERNOON WITH SPEEDS GENERALLY 15-30 KTS WITH GUSTS UP TO 40
KTS. WINDS SHOULD CONTINUE TO INCREASE SLOWLY THROUGH THE EVENING
HOURS...ESPECIALLY IN THE SOUTHERN GREAT BASIN AND INYO COUNTY.
SPOTTY AREAS OF BLOWING DUST HAVE BEEN REPORTED THIS AFTERNOON...AND
CAN BE EXPECTED THROUGH THE EVENING HOURS. SPEEDS SHOULD BEGIN TO
DECREASE RAPIDLY AFTER 09Z. MOUNTAIN WAVE ACTIVITY IS POSSIBLE
DOWNSTREAM OF THE SIERRA, WHITES, AND SPRING MOUNTAINS, AND
MECHANICAL TURBULENCE IS LIKELY THROUGH THE OVERNIGHT HOURS. A COLD
FRONT WILL SWEEP ACROSS THE AREA OVERNIGHT AND TOMORROW MORNING,
SWITCHING WINDS TO NORTH/NORTHWEST. DURING AND JUST AFTER FRONTAL
PASSAGE, WINDS MAY PICK UP (10-20 KTS), BUT OVERALL SPEEDS WILL BE
CONSIDERABLY LOWER TOMORROW THAN THOSE OBSERVED TODAY. BRIEF SHOT OF
LIGHT PRECIPITATION IS EXPECTED IN THE SIERRA AND WHITE MOUNTAINS
THIS EVENING/OVERNIGHT WITH BKN-OVC 050-120 CIGS AND SOME MOUNTAIN
OBSCURATIONS POSSIBLE...OTHERWISE FEW-SCT MID AND HIGH CLOUDS ARE
ANTICIPATED FOR MOST OF THE REGION THROUGH THE PERIOD.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTERS SHOULD REPORT ANY
SIGNIFICANT WEATHER ACCORDING TO STANDARD OPERATING PROCEDURES.
$$
SHORT TERM...ADAIR
LONG TERM.... MORGAN
AVIATION....SHAFER
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
Area Forecast Discussion
National Weather Service Reno NV
303 PM PDT FRI APR 22 2016
.SYNOPSIS...
A strong Pacific storm will continue to move through the Sierra
and Western Nevada tonight. Rain and heavy mountain snow are
expected this evening near and south of I-80. A break is expected
Saturday before more showers are expected Sunday into Monday with
another system. Unsettled weather will continue through next week
with below average temperatures.
&&
.SHORT TERM...
A strong spring storm continues to move through. Heavy snow is
falling in the Sierra with rates approaching 3"/hr. It is best to
avoid travel in the Sierra for the next few hours if possible.
Heavy convective snowfall continues in the Sierra with the bands
extending from Westwood south into Bridgeport. Heavy snow is
falling above 6000 feet, with the snow level locally down to 4500
feet in the heaviest bands. Latest satellite/radar trends support
the HRRR in keeping the heaviest rain/snow going thru 03Z near and
south of I-80. After there will be a rapid reduction in showers as
the upper forcing moves east and the airmass stabilizes.
Until then, another 6+ inches of snow is possible above 7000 feet
with another 2-4" down to 5500-6000 feet. Rainfall into Western NV
will be heaviest in the Sierra front where an additional 1/4" of
rain is possible. It may mix with snow at times in the foothills
while lighter amounts are expected toward the highway 95 corridor.
Winds are much weaker along the Sierra Front with the precip
falling, but strong gusts continue east of a Bridgeport to
Lovelock line. Will cancel the advisory for Reno-Carson-Minden,
but leave the remainder as the winds continue there.
Behind this storm, a break is expected Saturday with continued
cool temps, but lighter winds and dry conditions. Another upper
low is expected Sunday afternoon into Monday. Showers are expected
Sunday afternoon with enough instability for a few thunderstorms
as well. The core of the low will move overhead Monday morning
with much colder air. Snow levels will fall to near the valley
floors. While this storm will have some moisture with it, the best
forcing is expected to remain over Eastern NV so we are not
expecting another big precip event. However, there remains a
threat (low at this time) of some light snowfall during the Monday
morning commute along the I-80 and highway 50 corridors. Wallmann
.LONG TERM...Monday Night through Friday...
Unsettled weather pattern is expected to continue through next
week as late season storm systems line up to move into the West
Coast. Wednesday-Friday could be a rather wet period for much of
the region with potential for additional snow in higher
elevations.
For Monday night, the first upper low is likely to be on its way
out with lingering rain and snow showers diminishing. Tuesday
still looks like the least active weather day, although a few
showers remain possible as residual moisture will remain in place.
Even though temperatures are expected to increase about 10-15
degrees from Monday, highs in the lower 60s and around 50 degrees
near the Sierra will still be a few degrees below average for late
April.
For next Wednesday-Friday, medium range guidance continues to
indicate a potent low pressure tracking southward along the
California coast, then swing inland across the southwest US (or
possibly farther north into eastern NV). Despite this southerly
track, a broad area of upper divergence and instability is
projected to set up over the Sierra and western NV, along with a
decent tap of Pacific moisture. A few thunderstorms are also
possible each afternoon, although the better instability looks to
be trending north of I-80 by next Friday. Current projections
favor the best overall rain and snow chances Wednesday night and
higher thunderstorm potential on Thursday, but this could vary
depending on the eventual storm track. Widespread cloud cover will
keep daytime temps a few degrees below average each day, with
nighttime temps slightly above average. Early snow level
projections generally range from 6000-7000 feet in the Sierra,
although these snow levels could occasionally drop several hundred
feet during convection or heavier precip bands. MJD
&&
.AVIATION...
The most significant weather effects on aviation will continue
through this evening with IFR/LIFR cigs/vsby in snow near the
Sierra including KTVL/KTRK/KMMH, and a few inches of snow
accumulating on pavement. For lower elevations including KRNO-
KCXP, rain will produce MVFR cigs/vsby with mountain obscurations,
IFR at times during heavier rain bands. The strongest winds have
ended at KRNO-KCXP but some gusts to 35 KT remain possible. KMMH
may receive stronger gusts above 40 KT until 03z.
Later tonight, if cloud cover breaks up sufficiently, areas of
FZFG would develop across many Sierra valleys around Tahoe and
northeast CA, including KTRK. For Saturday, generally VFR
conditions are expected with lighter winds. MJD
&&
.REV Watches/Warnings/Advisories...
NV...Winter Weather Advisory until 11 PM PDT this evening NVZ002.
Wind Advisory until 8 PM PDT this evening NVZ001-004.
CA...Winter Weather Advisory until 5 PM PDT this afternoon above 5500
feet in CAZ071.
Wind Advisory until 8 PM PDT this evening CAZ073.
Winter Weather Advisory until 11 PM PDT this evening CAZ072.
&&
$$
For more information from the National Weather Service visit...
http://weather.gov/reno
AREA FORECAST DISCUSSION
NWS ELKO NV
248 AM PDT FRI APR 22 2016
.SYNOPSIS...BREEZY ACROSS NORTHERN NEVADA TODAY WITH SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS...CENTRAL NEVADA WILL BE DRIER
AND WINDIER THIS AFTERNOON. COOLER THIS WEEKEND WITH INCREASING
SHOWER ACTIVITY. AS COLDER AIR MOVES IN LATE SUNDAY INTO EARLY
NEXT WEEK...VALLEY RAINS WILL TRANSITION TO SNOW IN MANY
LOCATIONS. UNSETTLED WEATHER CONTINUES THROUGH MUCH OF NEXT WEEK.
&&
.SHORT TERM...TODAY THROUGH SUNDAY. TROUGH ENERGY MOVING IN OVER
NORTHERN AND CENTRAL CALIFORNIA TODAY RESULTS IN SOUTHWESTERLY
FLOW OVER NEVADA. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
WILL SPREAD INTO NORTHWESTERN NEVADA LATE THIS MORNING AND
PROGRESS INTO NORTH-CENTRAL NEVADA AND PORTIONS OF NORTHEASTERN
ELKO COUNTY BY THIS AFTERNOON. SOUTHERLY WINDS WILL BE BREEZY OVER
NORTHERN NEVADA WITH AREAS OF BLOWING DUST. CENTRAL NEVADA WILL BE
DRIER AND WINDIER THAN NORTHERN NEVADA TODAY AS THE LEADING EDGE
OF THE JET STREAM MOVES UP UNDER THE APPROACHING TROUGH. EXPANDED
THE WIND ADVISORY TO INCLUDE SOUTHERN LANDER AND EUREKA COUNTIES
AS WELL AS ELKO COUNTY EAST OF THE RUBY MOUNTAINS. THESE NEW WIND
ADVISORY AREAS WILL BE ON THE LIGHTER END OF THE ADVISORY LEVEL
WINDS...WITH STRONGEST WINDS TODAY STILL EXPECTED ACROSS CENTRAL
NEVADA. HIGH TEMPERATURES ACROSS NORTHWESTERN NEVADA WILL BE QUITE
A BIT COOLER TODAY THAN YESTERDAY AS THE TROUGH NEARS. CENTRAL AND
NORTHEASTERN NEVADA WILL BE A LITTLE COOLER THAN YESTERDAY...BUT
STILL WELL ABOVE NORMAL DUE TO STRONG SOUTHERLY FLOW.
THIS EVENING WINDS WILL DIMINISH AS TROUGH ENERGY FROM NORTHERN
CALIFORNIA SLIDES IN OVER NORTHERN NEVADA. COOLER AIR MOVES IN
WITH THE TROUGH TONIGHT WITH VALLEY RAIN AND MOUNTAIN SNOWS. BY
EARLY SATURDAY MORNING SOME OF THE HIGHER ELEVATION VALLEY
LOCATIONS MAY SEE A DUSTING TO POSSIBLY A HALF INCH OF
SNOW...GENERALLY AREAS ABOVE 7000 FEET. SHOWERS CONTINUE ON
SATURDAY BEFORE TAPERING OFF SATURDAY NIGHT AS THE TROUGH EXITS
OFF TO THE EAST.
A SECOND STORM SYSTEM WILL APPROACH FROM THE PACIFIC NORTHWEST
EARLY SUNDAY MORNING...WITH ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS OVER MOST OF NORTHERN AND PORTIONS OF CENTRAL NEVADA
BY SUNDAY AFTERNOON.
.LONG TERM...SUNDAY NIGHT THROUGH NEXT THURSDAY. MODELS ARE IN
PRETTY GOOD AGREEMENT DEPICTING TWO BACK TO BACK MOIST LOW
PRESSURE SYSTEMS TO MOVE THROUGH THE GREAT BASIN. UNSETTLED
WEATHER IS EXPECTED THROUGHOUT THE EXTENDED PERIOD.
SUNDAY NIGHT THROUGH TUESDAY. THIS PERIOD WILL HAVE THE GREATEST
IMPACT FROM SNOWFALL. THE PLACEMENT OF AN UPPER LOW TO IMPACT THE
GREAT BASIN IS ESSENTIALLY THE SAME AS ON PREVIOUS MODEL RUNS
HOWEVER MODELS HAVE MADE ADJUSTMENTS IN THE PROPOSED TRACK OF THE
LOW CENTER. LOW PRESSURE WILL MOVE IN OFF THE PACIFIC...TRAVERSE
OREGON...AND WILL PARALLEL THE SIERRA-NEVADA RANGE WHILE CENTRAL
LOW PRESSURE STAYS EAST THE SIERRA-NEVADA RANGE. THIS WILL FAVOR
THE EASTERN HALF OF THE STATE FOR RECEIVING A GOOD MOIST FLOW. NYE
COUNTY SEEMS TO BE THE SOUTHERN-MOST EXTENT MODELED FOR THE LOW
CENTER MONDAY AFTERNOON BEFORE IT BEGINS TO EJECT EAST-
NORTHEAST...PROVIDING A GOOD WRAP-AROUND MOISTURE EFFECT FOR
NORTHEAST NEVADA. SNOW LEVELS WILL BE FALLING TO THE VALLEY FLOORS
WEST TO EAST MONDAY THUS SNOW SHOULD FALL IN THE VALLEYS MONDAY
THROUGH MONDAY NIGHT. TRAVEL IMPACTS SHOULD BE MINIMAL DURING THE
DAY MONDAY SINCE ROAD TEMPERATURES WILL BE ELEVATED. MONDAY
EVENING MAY GET A LITTLE DICEY EAST OF THE RUBY MOUNTAINS AS
TEMPERATURES FALL BUT THEN PRECIPITATION RATES SHOULD DECREASE AS
THE LOW CENTER MOVES EAST OF THE STATE. THERE IS THE POSSIBILITY
FOR SEVERAL INCHES OF WRAP-AROUND SNOWFALL IN THE COOLER AIR OVER
NORTHERN ELKO COUNTY MONDAY THROUGH TUESDAY. AT THIS
JUNCTURE...THE BIGGEST IMPACT IS EXPECTED ACROSS NORTHERN ELKO
COUNTY...POSSIBLY RECEIVING SEVERAL INCHES OF VALLEY SNOW
ACCUMULATION. THE JARBIDGE WILDERNESS AREA NEAR THE IDAHO BORDER
WITH ELKO COUNTY COULD RECEIVE 8-10 INCHES OF SNOW. SHOWERS WILL
TAPER OFF TUESDAY.
TUESDAY NIGHT THROUGH THURSDAY. LOW PRESSURE CIRCULATING OFF THE
CANADIAN COAST WILL SPIN OFF A POTENT SHORTWAVE THAT WILL TRACK
VERY SIMILAR TO THE PREVIOUS STORM...THEN GET RE-ENFORCED BY THE
MAIN CANADIAN UPPER LOW CENTER MOVING DOWN INTO THE BASE OF THE
MEAN TROUGH THAT WILL GET CARVED OUT OVER SOUTHERN NEVADA AND
SOUTHERN CALIFORNIA THURSDAY. THE AIR MASS IS NOT CURRENTLY
MODELED TO BE EXCEPTIONALLY COLD HOWEVER THERE IS POTENTIAL FOR
SIGNIFICANT MOUNTAIN SNOWFALL ACROSS MUCH OF NORTHERN AND CENTRAL
NEVADA.
&&
.AVIATION...VFR WILL BE THE PREVAILING CONDITION AT KWMC KEKO KELY
AND KTPH THROUGH SATURDAY MORNING. HOWEVER A COLD FRONT WILL BE
APPROACHING AND MOVING THROUGH THE AREA TODAY AND TONIGHT.
THUNDERSTORMS COULD AFFECT ALL FOUR SITES THIS AFTERNOON. GUSTY
WINDS AHEAD OF AND ALONG THE FRONT MAY CAUSE BLOWING DUST AND
REDUCED VISIBILITY AT ALL FOUR SITES. AS SHOWER ACTIVITY INCREASES
TONIGHT AND EARLY SATURDAY...MVFR CIGS ARE POSSIBLE.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 11 AM THIS MORNING TO 9 PM PDT THIS EVENING
FOR NORTHEASTERN NYE COUNTY-NORTHWESTERN NYE COUNTY-SOUTH
CENTRAL ELKO COUNTY-SOUTHEASTERN ELKO COUNTY-SOUTHERN LANDER
COUNTY AND SOUTHERN EUREKA COUNTY-WHITE PINE COUNTY.
&&
$$
96/92/92
Area Forecast Discussion
National Weather Service Reno NV
238 AM PDT FRI APR 22 2016
SYNOPSIS...
A potent Pacific storm will move through the region today. Strong
and gusty winds can be expected along with valley rain and
mountain snow. A brief break is expected Saturday before a series
of systems is expected next week. Showery conditions are expected
Sunday afternoon and beyond along with cool temperatures.
&&
.SHORT TERM...
Moderate spring storm (by Sierra standards) with a strong cold
front is currently moving on shore and will impact the Sierra and
western Nevada today. No major changes were made to the forecast
with all winter weather and wind advisories still on track today.
Travel over Sierra passes today will very likely be impacted by
winter driving conditions so plan accordingly.
Current radar shows the leading edge of the strong cold front
currently moving into northern California. Instability ahead of
the front is currently creating some convective showers along the
Sierra crest around Donner Summit with off and on light showers
remaining possible until the cold front arrives. Precipitation may
start out as rain but is expected to change over to snow
relatively quickly above 7000 feet. HRRR model solutions show the
leading edge of the main cold front and heavy precipitation will
impact the Sierra around 10-11 am today with passes in the
northern Sierra (Yuba and Fredonyer) receiving heavy precipitation
as early as 7-8 am. For more details on snow amounts and timing
see the winter weather advisories.
Precipitation is expected to quickly spill into the lee of the
Sierra due to very unstable environment along the cold front and
strong upper level jet support. This will lead to periods of
brief moderate precipitation in western Nevada valleys. The
convective nature of this system will lead to wide disparities in
rain and snow amounts from one place to another depending on where
convective bands set up. There will also be the chance for a few
isolated thunderstorms today as the front quickly moves into
western Nevada.
Winds are expected to be quite strong today in western Nevada as
surface gradients tighten and instability will allow strong 700
mb winds to mix to the surface. Widespread winds of 25-35 mph
should be expected with peaks gusts of 50 mph and up to 60 mph in
wind prone areas. This could create some localized areas of
blowing dust which even if brief can cause hazardous driving
conditions.
This system is quite progressive with the cold front expected to
move into Utah by late Friday night. A few showers may linger
along the Sierra crest but the precipitation should be over by
Saturday morning. Brief shortwave ridging on Saturday will be
replaced by another trough digging into the area on Sunday. This
could bring another round of cold air and precipitation on Sunday
into Monday. Zach
.LONG TERM...Monday through Thursday...
Unsettled weather pattern is expected to continue through next week
as late season storm systems line up to move into the West Coast.
There is good agreement in the models that cold low pressure will
remain over the Great Basin on Monday with additional showers and
convective precipitation bands due to unstable conditions.
There is a possibility that we could see snow levels dropping to
near 4500 feet on Monday morning as the coldest air is expected to
move over the Sierra and western NV. Forecast confidence on seeing
snow to the valley floors is low, although there is a chance we
could see light slushy accumulations in the valleys and foothills of
western NV. Models have trended further east into central and
northeastern NV with the heaviest bands, but we will need to keep a
close eye on how this evolves over the next couple days as it has
potential to affect the Monday morning commute. High temperatures on
Monday will struggle to get out of the 40s in western NV and 30s in
the Sierra due to the low pressure overhead and abundant cloud
cover/showers. Low pressure will move out of the area Tuesday with
warming temperatures and clearing skies.
By Wednesday, another low pressure system is expected to move
into northern CA/NV bringing additional chances for showers and
increasing clouds. There is much uncertainty for the Wednesday-
Thursday timeframe regarding precipitation amounts, although this
system doesn`t look to be quite as cold as the the Monday system.
Hoon
&&
.AVIATION...
Multiple weather-related impacts to aviation are expected through
tonight as potent low pressure moves across the region.
Winds will be the primary impact today with wind shear potential,
mainly at KRNO-KCXP-KMMH as winds above the surface increase.
Widespread turbulent conditions are likely through today with peak
gusts up to 45 kt in the lower elevations and Sierra ridge gusts
near 80 kt.
Rain and snow will reach the northern Sierra early this morning,
then spread into western Nevada by this afternoon. Snow levels
should fall to 6000-7000 feet by this afternoon, which may bring IFR
conditions to KTRK, KTVL and KMMH. Snow accumulations on paved
surfaces are unlikely during the day, but some light accumulations
up to 2 inches are possible with the back edge of the snow moving
through this evening. For the western Nevada terminals including
KRNO and KCXP, precipitation will be all rain with reduced ceilings
for MVFR conditions this afternoon-evening. MJD/Hoon
&&
.REV Watches/Warnings/Advisories...
NV...Lake Wind Advisory until 8 AM PDT this morning for Lake Tahoe in
NVZ002.
Winter Weather Advisory from 8 AM this morning to 11 PM PDT this
evening NVZ002.
Wind Advisory from 11 AM this morning to 8 PM PDT this evening
NVZ001-004.
Wind Advisory until 5 PM PDT this afternoon NVZ003.
CA...Winter Weather Advisory from 5 AM early this morning to 5 PM PDT
this afternoon above 5500 feet in CAZ071.
Wind Advisory from 5 AM early this morning to 8 PM PDT this
evening CAZ073.
Lake Wind Advisory until 8 AM PDT this morning for Lake Tahoe in
CAZ072.
Winter Weather Advisory from 8 AM this morning to 11 PM PDT this
evening CAZ072.
&&
$$
For more information from the National Weather Service visit...
http://weather.gov/reno
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1152 AM MDT FRI APR 22 2016
.AVIATION...
18Z TAF CYCLE
SOUTHERLY WINDS TODAY WILL DELIVER AN INFLUX OF MOISTURE FOR
-SHRA/TSRA AFT 22Z BTWN THE CONT DVD AND THE CENTRAL MT CHAIN.
GREATEST CHANCE FOR GUSTY OUTFLOW WINDS AND MEASURABLE PRECIP
WILL OCCUR AROUND KAEG...KABQ...AND KSAF BTWN 00Z AND 06Z. NO
IMPACTS BELOW VFR ARE EXPECTED. ACTIVITY MAY ALSO SLIDE OFF THE
CENTRAL MT CHAIN TO KLVS AND KROW DURING THE EVENING/OVERNIGHT
PERIOD BUT CONFIDENCE NOT AS HIGH THERE. DRIER SW FLOW WILL MOVE
IN SATURDAY WITH A FEW REMNANT -SHRA POSSIBLE OVER THE NORTHERN
HIGH TERRAIN AND THE NE PLAINS.
GUYER
&&
.PREV DISCUSSION...333 AM MDT FRI APR 22 2016...
.SYNOPSIS...
MODEST MOISTURE CONTINUES TO WORK ITS WAY INTO CENTRAL NEW MEXICO
FROM THE SOUTHEAST AS A COUPLE OF LOW PRESSURE SYSTEMS CROSS THE
WEST COAST. THESE SYSTEMS WILL SKIRT AROUND NEW MEXICO TO THE
NORTH AND SOUTH...BUT THE MOISTURE IN PLACE WILL HELP SPARK
SCATTERED TO ISOLATED SHOWERS AND THUNDERSTORMS MAINLY OVER
CENTRAL AREAS THIS AFTERNOON AND EVENING...THEN ALONG AND TO A
LESSER EXTENT EAST OF THE CENTRAL MOUNTAIN CHAIN ON SATURDAY. THE
JET STREAM WILL MOVE OVER THE COLORADO AND NEW MEXICO BORDER ON
SATURDAY WITH SURFACE WIND GUSTS PROBABLY REACHING 50 MPH OVER A
GOOD PORTION OF NORTHERN NEW MEXICO IN THE AFTERNOON. FIRE WEATHER
CONCERNS WILL RAMP UP WEST OF THE CENTRAL MOUNTAIN CHAIN
SATURDAY...THEN CONTINUE TO PLAGUE PORTIONS OF NORTHERN AND
CENTRAL NEW MEXICO THROUGH TUESDAY AS DRIER AIR MOVES IN FROM THE
WEST AND BREEZY TO WINDY CONDITIONS RETURN DAILY.
&&
.DISCUSSION...
SOME STORMS WILL PRODUCE LITTLE OR NO RAIN WEST OF THE
CONTINENTAL DIVIDE TODAY...THEN AT LOWER ELEVATIONS BETWEEN THE
CENTRAL MOUNTAIN CHAIN AND CONTINENTAL DIVIDE ON SATURDAY.
MEANWHILE...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS
SATURDAY AFTERNOON AND EVENING IN UNION COUNTY/FAR NE NM.
A PACIFIC COLD FRONT WILL CROSS FROM THE WEST SATURDAY AND
SATURDAY NIGHT USHERING COOLER TEMPERATURES AND DRY AIR FOR
SUNDAY. READINGS WILL VARY AROUND NORMAL MOST PLACES...EXCEPT ON
THE FAR EASTERN PLAINS WHERE READINGS 4 TO 10 DEGREES ABOVE NORMAL
SHOULD PERSIST. BREEZY TO WINDY CONDITIONS ARE EXPECTED TO RETURN
IN THE VICINITY OF THE I-40 CORRIDOR OF EASTERN NM SUNDAY AFTERNOON
WITH WESTERLY DOWNSLOPE FLOW.
ANOTHER UPPER LEVEL LOW PRESSURE SYSTEM WILL DIG INTO THE GREAT
BASIN ON MONDAY...THEN PASS NORTH OF NEW MEXICO ON TUESDAY
STEERING THE JET STREAM SQUARELY OVER THE FORECAST AREA. THIS WILL
KEEP BREEZY TO WINDY CONDITIONS IN THE FORECAST ACROSS WESTERN
AREAS MONDAY AND AREAWIDE TUESDAY. IT WILL CAUSE FIRE WEATHER
CONCERNS TO PERSIST.
SHORT WAVE RIDGING WILL CAUSE WINDS TO SETTLE DOWN WEDNESDAY...BUT
SW FLOW LOOKS TO STRENGTHEN AGAIN DURING THE LATTER HALF OF THE
WEEK AS YET ANOTHER UPPER LEVEL LOW PRESSURE SYSTEM DIGS INTO THE
GREAT BASIN AND APPROACHES NM FROM THE W OR NW.
44
&&
.FIRE WEATHER...
CRITICAL CONDITIONS WILL BE AT LEAST SPOTTY SATURDAY THROUGH MONDAY
WITH MORE WIDESPREAD CRITICAL CONDITIONS POSSIBLE NEXT TUESDAY. VENT
RATES WILL BE GOOD TO EXCELLENT TODAY THROUGH NEXT WEDNESDAY.
THE LATEST MODELS QUITE CONSISTENT WITH PREVIOUS VERSIONS IN THE
SHORTER TERM. THE UPPER RIDGE WILL BE MOVING OVER NEW MEXICO TODAY
AND THEN TO THE EAST OF THE STATE SATURDAY AS AN UPPER LOW TRACKS
INTO THE GREAT BASIN AND THROUGH THE CENTRAL ROCKIES. WINDS ALOFT
WILL TRANSITION TO SOUTHWEST LATER TODAY AND TONIGHT...AND WILL
STRENGTHEN WITH TIME. LOW LEVEL MOISTURE APPEARS TO BE MIGRATING INTO
SOUTH CENTRAL NM AT THIS TIME...AND A SUSTAINED SOUTHEAST TO SOUTH
FLOW REMAINS FORECAST...WHICH WOULD BRING HIGHER DEW POINTS UP THE
RGV AND TOWARDS THE CONTDVD...AS THE GFS HAS BEEN INDICATING FOR
SEVERAL DAYS. RUC AND HRRR NOW JUMPING ONBOARD BREAKING OUT CONVECTION
ALONG THE CONTDVD AND CENTRAL MT CHAIN BY MIDAFTERNOON. WITH THE
POOR RH RECOVERIES ALONG/WEST OF THE CONTDVD AT THIS TIME...CAN/T HELP BUT
THINK THERE MAY BE SOME HIGH BASED VIRGA SHOWERS/ISOLD DRY LIGHTNING
OVER THIS AREA LATER TODAY...GIVEN THE INSTABILITY FORECAST BY THE NAM12.
CONVECTION THIS EVENING MAY RESULT IN SOME WETTING PRECIPITATION BETWEEN THE
CONTDVD AND EAST SLOPES OF THE CENTRAL MT CHAIN.
SATURDAY STILL LOOKS TO SEE WIND GUSTS TO AROUND 45 OR 50 MPH AS THE
WESTERLY WINDS SHOVE THE LOW LEVEL MOISTURE FROM WEST TO EAST OVER
THE STATE. MIN RH VALUES FALL BELOW 15 PERCENT FOR PORTIONS OF THE
MIDDLE RGV AND WEST. DECIDED TO GO AHEAD WITH A FIRE WEATHER WATCH
FOR AREAS BELOW SNOWPACK FOR THE NORTHWEST/WEST CENTRAL AND MIDDLE RGV
ALTHOUGH MAINLY FOR BERNALILLO AND VALENCIA COUNTIES IF THE GRIDS
ARE CLOSE. NOT SURE OF THE STATE OF GREENUP AT THIS TIME...BUT RECENT
COOLER WEATHER MAY HAVE RETARDED IT. HIGHS WILL BE ABOVE AVERAGE...BUT
NOT OVERLY SO...IN THE RANGE OF 5 TO 10 DEGREES.
CONVECTION WILL BE FOCUSED OVER THE CENTRAL AND EAST SATURDAY/SATURDAY
NIGHT BUT SUNDAY LOOKS TO BE DRY. THERE MAY BE A FEW SHOWERS OR STORMS
ON THE DRIER SIDE FROM THE CENTRAL MT CHAIN WWD AS THE MOISTURE BECOMES
MORE SHALLOW ON SATURDAY. RIDGETOP WINDS MAY PERSIST SATURDAY NIGHT BEFORE
RELENTING SOMEWHAT SUNDAY UNDER ZONAL FLOW...BUT NOT ENOUGH TO
ELIMINATE THE POTENTIAL FOR CRITICAL CONDITIONS IN THE EAST CENTRAL
SUNDAY AFTERNOON. RH RECOVERIES SATURDAY AND SUNDAY NIGHT WILL BE
FAIR TO POOR FOR MANY LOCALES.
MONDAY THROUGH TUESDAY WILL SEE INCREASING WINDS AS ANOTHER SYSTEM
SWINGS THROUGH THE CENTRAL ROCKIES. POOR RH RECOVERIES LOOK TO BE
WIDESPREAD MONDAY NIGHT. HIGHS WILL FALL TO AROUND 5 TO 10 DEGREES
BELOW AVERAGE WEST AND CENTRAL AND TO NEAR AVERAGE EAST BY TUESDAY...
TO HELP MODERATE THE COMBO OF WIND AND SUB 15 PERCENT RH FROM THE
MIDDLE RGV TO THE EAST CENTRAL AND NORTHEAST PLAINS TUESDAY AFTERNOON...
WHERE CRITICAL CONDITIONS LOOK TO BE WIDESPREAD. ANY WETTING PRECIPITATION
WILL BE CONFINED TO THE HIGHER TERRAIN OF THE NORTHWEST AND NORTH CENTRAL
MONDAY THROUGH TUESDAY. GUSTY WEST WINDS MAY CONTINUE TUESDAY NIGHT BEFORE
SLACKING OFF. ANOTHER SYSTEM LINED UP FOR THE END OF NEXT WEEK BUT GFS
IS DRIER AND WINDIER...THE ECMWF IS WETTER.
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY EVENING
FOR THE FOLLOWING ZONES... NMZ101-105-106.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
525 AM MDT FRI APR 22 2016
.AVIATION...
12Z TAF CYCLE
UPPER RIDGE TO MOVE OVER NM FROM WEST TO EAST TODAY WITH FLOW
ALOFT BECOMING SWLY. MOIST LOW LEVEL SOUTHEAST WINDS TO TRANSPORT
MOISTURE UP THE RGV AND TOWARDS THE CONTDVD. MID LEVEL MOISTURE
INCREASING AS WELL...AND EXPECT ISOLD TO SCT SHRA AND TSRA TO
DEVELOP OVER THE HIGHER TERRAIN WITH GUSTS TO AROUND 40KT AFT 18Z.
MTS MAY BE BRIEFLY OBSCURED BY HEAVIER SHRA/TSRA IN WHICH
CIGS/VSBYS MAY FALL TO MVFR.
&&
.PREV DISCUSSION...333 AM MDT FRI APR 22 2016...
.SYNOPSIS...
MODEST MOISTURE CONTINUES TO WORK ITS WAY INTO CENTRAL NEW MEXICO
FROM THE SOUTHEAST AS A COUPLE OF LOW PRESSURE SYSTEMS CROSS THE
WEST COAST. THESE SYSTEMS WILL SKIRT AROUND NEW MEXICO TO THE
NORTH AND SOUTH...BUT THE MOISTURE IN PLACE WILL HELP SPARK
SCATTERED TO ISOLATED SHOWERS AND THUNDERSTORMS MAINLY OVER
CENTRAL AREAS THIS AFTERNOON AND EVENING...THEN ALONG AND TO A
LESSER EXTENT EAST OF THE CENTRAL MOUNTAIN CHAIN ON SATURDAY. THE
JET STREAM WILL MOVE OVER THE COLORADO AND NEW MEXICO BORDER ON
SATURDAY WITH SURFACE WIND GUSTS PROBABLY REACHING 50 MPH OVER A
GOOD PORTION OF NORTHERN NEW MEXICO IN THE AFTERNOON. FIRE WEATHER
CONCERNS WILL RAMP UP WEST OF THE CENTRAL MOUNTAIN CHAIN
SATURDAY...THEN CONTINUE TO PLAGUE PORTIONS OF NORTHERN AND
CENTRAL NEW MEXICO THROUGH TUESDAY AS DRIER AIR MOVES IN FROM THE
WEST AND BREEZY TO WINDY CONDITIONS RETURN DAILY.
&&
.DISCUSSION...
SOME STORMS WILL PRODUCE LITTLE OR NO RAIN WEST OF THE
CONTINENTAL DIVIDE TODAY...THEN AT LOWER ELEVATIONS BETWEEN THE
CENTRAL MOUNTAIN CHAIN AND CONTINENTAL DIVIDE ON SATURDAY.
MEANWHILE...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS
SATURDAY AFTERNOON AND EVENING IN UNION COUNTY/FAR NE NM.
A PACIFIC COLD FRONT WILL CROSS FROM THE WEST SATURDAY AND
SATURDAY NIGHT USHERING COOLER TEMPERATURES AND DRY AIR FOR
SUNDAY. READINGS WILL VARY AROUND NORMAL MOST PLACES...EXCEPT ON
THE FAR EASTERN PLAINS WHERE READINGS 4 TO 10 DEGREES ABOVE NORMAL
SHOULD PERSIST. BREEZY TO WINDY CONDITIONS ARE EXPECTED TO RETURN
IN THE VICINITY OF THE I-40 CORRIDOR OF EASTERN NM SUNDAY AFTERNOON
WITH WESTERLY DOWNSLOPE FLOW.
ANOTHER UPPER LEVEL LOW PRESSURE SYSTEM WILL DIG INTO THE GREAT
BASIN ON MONDAY...THEN PASS NORTH OF NEW MEXICO ON TUESDAY
STEERING THE JET STREAM SQUARELY OVER THE FORECAST AREA. THIS WILL
KEEP BREEZY TO WINDY CONDITIONS IN THE FORECAST ACROSS WESTERN
AREAS MONDAY AND AREAWIDE TUESDAY. IT WILL CAUSE FIRE WEATHER
CONCERNS TO PERSIST.
SHORT WAVE RIDGING WILL CAUSE WINDS TO SETTLE DOWN WEDNESDAY...BUT
SW FLOW LOOKS TO STRENGTHEN AGAIN DURING THE LATTER HALF OF THE
WEEK AS YET ANOTHER UPPER LEVEL LOW PRESSURE SYSTEM DIGS INTO THE
GREAT BASIN AND APPROACHES NM FROM THE W OR NW.
44
&&
.FIRE WEATHER...
CRITICAL CONDITIONS WILL BE AT LEAST SPOTTY SATURDAY THROUGH MONDAY
WITH MORE WIDESPREAD CRITICAL CONDITIONS POSSIBLE NEXT TUESDAY. VENT
RATES WILL BE GOOD TO EXCELLENT TODAY THROUGH NEXT WEDNESDAY.
THE LATEST MODELS QUITE CONSISTENT WITH PREVIOUS VERSIONS IN THE
SHORTER TERM. THE UPPER RIDGE WILL BE MOVING OVER NEW MEXICO TODAY
AND THEN TO THE EAST OF THE STATE SATURDAY AS AN UPPER LOW TRACKS
INTO THE GREAT BASIN AND THROUGH THE CENTRAL ROCKIES. WINDS ALOFT
WILL TRANSITION TO SOUTHWEST LATER TODAY AND TONIGHT...AND WILL
STRENGTHEN WITH TIME. LOW LEVEL MOISTURE APPEARS TO BE MIGRATING INTO
SOUTH CENTRAL NM AT THIS TIME...AND A SUSTAINED SOUTHEAST TO SOUTH
FLOW REMAINS FORECAST...WHICH WOULD BRING HIGHER DEW POINTS UP THE
RGV AND TOWARDS THE CONTDVD...AS THE GFS HAS BEEN INDICATING FOR
SEVERAL DAYS. RUC AND HRRR NOW JUMPING ONBOARD BREAKING OUT CONVECTION
ALONG THE CONTDVD AND CENTRAL MT CHAIN BY MIDAFTERNOON. WITH THE
POOR RH RECOVERIES ALONG/WEST OF THE CONTDVD AT THIS TIME...CAN/T HELP BUT
THINK THERE MAY BE SOME HIGH BASED VIRGA SHOWERS/ISOLD DRY LIGHTNING
OVER THIS AREA LATER TODAY...GIVEN THE INSTABILITY FORECAST BY THE NAM12.
CONVECTION THIS EVENING MAY RESULT IN SOME WETTING PRECIPITATION BETWEEN THE
CONTDVD AND EAST SLOPES OF THE CENTRAL MT CHAIN.
SATURDAY STILL LOOKS TO SEE WIND GUSTS TO AROUND 45 OR 50 MPH AS THE
WESTERLY WINDS SHOVE THE LOW LEVEL MOISTURE FROM WEST TO EAST OVER
THE STATE. MIN RH VALUES FALL BELOW 15 PERCENT FOR PORTIONS OF THE
MIDDLE RGV AND WEST. DECIDED TO GO AHEAD WITH A FIRE WEATHER WATCH
FOR AREAS BELOW SNOWPACK FOR THE NORTHWEST/WEST CENTRAL AND MIDDLE RGV
ALTHOUGH MAINLY FOR BERNALILLO AND VALENCIA COUNTIES IF THE GRIDS
ARE CLOSE. NOT SURE OF THE STATE OF GREENUP AT THIS TIME...BUT RECENT
COOLER WEATHER MAY HAVE RETARDED IT. HIGHS WILL BE ABOVE AVERAGE...BUT
NOT OVERLY SO...IN THE RANGE OF 5 TO 10 DEGREES.
CONVECTION WILL BE FOCUSED OVER THE CENTRAL AND EAST SATURDAY/SATURDAY
NIGHT BUT SUNDAY LOOKS TO BE DRY. THERE MAY BE A FEW SHOWERS OR STORMS
ON THE DRIER SIDE FROM THE CENTRAL MT CHAIN WWD AS THE MOISTURE BECOMES
MORE SHALLOW ON SATURDAY. RIDGETOP WINDS MAY PERSIST SATURDAY NIGHT BEFORE
RELENTING SOMEWHAT SUNDAY UNDER ZONAL FLOW...BUT NOT ENOUGH TO
ELIMINATE THE POTENTIAL FOR CRITICAL CONDITIONS IN THE EAST CENTRAL
SUNDAY AFTERNOON. RH RECOVERIES SATURDAY AND SUNDAY NIGHT WILL BE
FAIR TO POOR FOR MANY LOCALES.
MONDAY THROUGH TUESDAY WILL SEE INCREASING WINDS AS ANOTHER SYSTEM
SWINGS THROUGH THE CENTRAL ROCKIES. POOR RH RECOVERIES LOOK TO BE
WIDESPREAD MONDAY NIGHT. HIGHS WILL FALL TO AROUND 5 TO 10 DEGREES
BELOW AVERAGE WEST AND CENTRAL AND TO NEAR AVERAGE EAST BY TUESDAY...
TO HELP MODERATE THE COMBO OF WIND AND SUB 15 PERCENT RH FROM THE
MIDDLE RGV TO THE EAST CENTRAL AND NORTHEAST PLAINS TUESDAY AFTERNOON...
WHERE CRITICAL CONDITIONS LOOK TO BE WIDESPREAD. ANY WETTING PRECIPITATION
WILL BE CONFINED TO THE HIGHER TERRAIN OF THE NORTHWEST AND NORTH CENTRAL
MONDAY THROUGH TUESDAY. GUSTY WEST WINDS MAY CONTINUE TUESDAY NIGHT BEFORE
SLACKING OFF. ANOTHER SYSTEM LINED UP FOR THE END OF NEXT WEEK BUT GFS
IS DRIER AND WINDIER...THE ECMWF IS WETTER.
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY EVENING
FOR THE FOLLOWING ZONES... NMZ101-105-106.
&&
$$
AREA FORECAST DISCUSSION...CORRECTED
NWS ALBUQUERQUE NM
333 AM MDT FRI APR 22 2016
CORRECTED SECOND PARAGRAPH OF DISCUSSION SECTION
.SYNOPSIS...
MODEST MOISTURE CONTINUES TO WORK ITS WAY INTO CENTRAL NEW MEXICO
FROM THE SOUTHEAST AS A COUPLE OF LOW PRESSURE SYSTEMS CROSS THE
WEST COAST. THESE SYSTEMS WILL SKIRT AROUND NEW MEXICO TO THE
NORTH AND SOUTH...BUT THE MOISTURE IN PLACE WILL HELP SPARK
SCATTERED TO ISOLATED SHOWERS AND THUNDERSTORMS MAINLY OVER
CENTRAL AREAS THIS AFTERNOON AND EVENING...THEN ALONG AND TO A
LESSER EXTENT EAST OF THE CENTRAL MOUNTAIN CHAIN ON SATURDAY. THE
JET STREAM WILL MOVE OVER THE COLORADO AND NEW MEXICO BORDER ON
SATURDAY WITH SURFACE WIND GUSTS PROBABLY REACHING 50 MPH OVER A
GOOD PORTION OF NORTHERN NEW MEXICO IN THE AFTERNOON. FIRE WEATHER
CONCERNS WILL RAMP UP WEST OF THE CENTRAL MOUNTAIN CHAIN
SATURDAY...THEN CONTINUE TO PLAGUE PORTIONS OF NORTHERN AND
CENTRAL NEW MEXICO THROUGH TUESDAY AS DRIER AIR MOVES IN FROM THE
WEST AND BREEZY TO WINDY CONDITIONS RETURN DAILY.
&&
.DISCUSSION...
SOME STORMS WILL PRODUCE LITTLE OR NO RAIN WEST OF THE
CONTINENTAL DIVIDE TODAY...THEN AT LOWER ELEVATIONS BETWEEN THE
CENTRAL MOUNTAIN CHAIN AND CONTINENTAL DIVIDE ON SATURDAY.
MEANWHILE...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS
SATURDAY AFTERNOON AND EVENING IN UNION COUNTY/FAR NE NM.
A PACIFIC COLD FRONT WILL CROSS FROM THE WEST SATURDAY AND
SATURDAY NIGHT USHERING COOLER TEMPERATURES AND DRY AIR FOR
SUNDAY. READINGS WILL VARY AROUND NORMAL MOST PLACES...EXCEPT ON
THE FAR EASTERN PLAINS WHERE READINGS 4 TO 10 DEGREES ABOVE NORMAL
SHOULD PERSIST. BREEZY TO WINDY CONDITIONS ARE EXPECTED TO RETURN
IN THE VICINITY OF THE I-40 CORRIDOR OF EASTERN NM SUNDAY AFTERNOON
WITH WESTERLY DOWNSLOPE FLOW.
ANOTHER UPPER LEVEL LOW PRESSURE SYSTEM WILL DIG INTO THE GREAT
BASIN ON MONDAY...THEN PASS NORTH OF NEW MEXICO ON TUESDAY
STEERING THE JET STREAM SQUARELY OVER THE FORECAST AREA. THIS WILL
KEEP BREEZY TO WINDY CONDITIONS IN THE FORECAST ACROSS WESTERN
AREAS MONDAY AND AREAWIDE TUESDAY. IT WILL CAUSE FIRE WEATHER
CONCERNS TO PERSIST.
SHORT WAVE RIDGING WILL CAUSE WINDS TO SETTLE DOWN WEDNESDAY...BUT
SW FLOW LOOKS TO STRENGTHEN AGAIN DURING THE LATTER HALF OF THE
WEEK AS YET ANOTHER UPPER LEVEL LOW PRESSURE SYSTEM DIGS INTO THE
GREAT BASIN AND APPROACHES NM FROM THE W OR NW.
44
&&
.FIRE WEATHER...
CRITICAL CONDITIONS WILL BE AT LEAST SPOTTY SATURDAY THROUGH MONDAY
WITH MORE WIDESPREAD CRITICAL CONDITIONS POSSIBLE NEXT TUESDAY. VENT
RATES WILL BE GOOD TO EXCELLENT TODAY THROUGH NEXT WEDNESDAY.
THE LATEST MODELS QUITE CONSISTENT WITH PREVIOUS VERSIONS IN THE
SHORTER TERM. THE UPPER RIDGE WILL BE MOVING OVER NEW MEXICO TODAY
AND THEN TO THE EAST OF THE STATE SATURDAY AS AN UPPER LOW TRACKS
INTO THE GREAT BASIN AND THROUGH THE CENTRAL ROCKIES. WINDS ALOFT
WILL TRANSITION TO SOUTHWEST LATER TODAY AND TONIGHT...AND WILL
STRENGTHEN WITH TIME. LOW LEVEL MOISTURE APPEARS TO BE MIGRATING INTO
SOUTH CENTRAL NM AT THIS TIME...AND A SUSTAINED SOUTHEAST TO SOUTH
FLOW REMAINS FORECAST...WHICH WOULD BRING HIGHER DEW POINTS UP THE
RGV AND TOWARDS THE CONTDVD...AS THE GFS HAS BEEN INDICATING FOR
SEVERAL DAYS. RUC AND HRRR NOW JUMPING ONBOARD BREAKING OUT CONVECTION
ALONG THE CONTDVD AND CENTRAL MT CHAIN BY MIDAFTERNOON. WITH THE
POOR RH RECOVERIES ALONG/WEST OF THE CONTDVD AT THIS TIME...CAN/T HELP BUT
THINK THERE MAY BE SOME HIGH BASED VIRGA SHOWERS/ISOLD DRY LIGHTNING
OVER THIS AREA LATER TODAY...GIVEN THE INSTABILITY FORECAST BY THE NAM12.
CONVECTION THIS EVENING MAY RESULT IN SOME WETTING PRECIPITATION BETWEEN THE
CONTDVD AND EAST SLOPES OF THE CENTRAL MT CHAIN.
SATURDAY STILL LOOKS TO SEE WIND GUSTS TO AROUND 45 OR 50 MPH AS THE
WESTERLY WINDS SHOVE THE LOW LEVEL MOISTURE FROM WEST TO EAST OVER
THE STATE. MIN RH VALUES FALL BELOW 15 PERCENT FOR PORTIONS OF THE
MIDDLE RGV AND WEST. DECIDED TO GO AHEAD WITH A FIRE WEATHER WATCH
FOR AREAS BELOW SNOWPACK FOR THE NORTHWEST/WEST CENTRAL AND MIDDLE RGV
ALTHOUGH MAINLY FOR BERNALILLO AND VALENCIA COUNTIES IF THE GRIDS
ARE CLOSE. NOT SURE OF THE STATE OF GREENUP AT THIS TIME...BUT RECENT
COOLER WEATHER MAY HAVE RETARDED IT. HIGHS WILL BE ABOVE AVERAGE...BUT
NOT OVERLY SO...IN THE RANGE OF 5 TO 10 DEGREES.
CONVECTION WILL BE FOCUSED OVER THE CENTRAL AND EAST SATURDAY/SATURDAY
NIGHT BUT SUNDAY LOOKS TO BE DRY. THERE MAY BE A FEW SHOWERS OR STORMS
ON THE DRIER SIDE FROM THE CENTRAL MT CHAIN WWD AS THE MOISTURE BECOMES
MORE SHALLOW ON SATURDAY. RIDGETOP WINDS MAY PERSIST SATURDAY NIGHT BEFORE
RELENTING SOMEWHAT SUNDAY UNDER ZONAL FLOW...BUT NOT ENOUGH TO
ELIMINATE THE POTENTIAL FOR CRITICAL CONDITIONS IN THE EAST CENTRAL
SUNDAY AFTERNOON. RH RECOVERIES SATURDAY AND SUNDAY NIGHT WILL BE
FAIR TO POOR FOR MANY LOCALES.
MONDAY THROUGH TUESDAY WILL SEE INCREASING WINDS AS ANOTHER SYSTEM
SWINGS THROUGH THE CENTRAL ROCKIES. POOR RH RECOVERIES LOOK TO BE
WIDESPREAD MONDAY NIGHT. HIGHS WILL FALL TO AROUND 5 TO 10 DEGREES
BELOW AVERAGE WEST AND CENTRAL AND TO NEAR AVERAGE EAST BY TUESDAY...
TO HELP MODERATE THE COMBO OF WIND AND SUB 15 PERCENT RH FROM THE
MIDDLE RGV TO THE EAST CENTRAL AND NORTHEAST PLAINS TUESDAY AFTERNOON...
WHERE CRITICAL CONDITIONS LOOK TO BE WIDESPREAD. ANY WETTING PRECIPITATION
WILL BE CONFINED TO THE HIGHER TERRAIN OF THE NORTHWEST AND NORTH CENTRAL
MONDAY THROUGH TUESDAY. GUSTY WEST WINDS MAY CONTINUE TUESDAY NIGHT BEFORE
SLACKING OFF. ANOTHER SYSTEM LINED UP FOR THE END OF NEXT WEEK BUT GFS
IS DRIER AND WINDIER...THE ECMWF IS WETTER.
&&
.AVIATION...
06Z TAF CYCLE
UPPER RIDGE ENTERING NM AT PRODUCT GENERATION TIME WILL MOVE OVER
THE STATE OVERNIGHT WITH FLOW ALOFT BECOMING SOUTHWEST LATER FRI.
BACK DOOR FRONT HAS BREACHED THE GAPS OF CENTRAL MT CHAIN AND WILL
CONTINUE TO GENERATE SPOTTY MODERATE E TO SE WINDS UNTIL NEAR OR A
LITTLE BEFORE DAWN. THIS UPSLOPE FLOW MAY STILL LEAD TO A FEW
PATCHES OF MVFR CIGS FROM THE EAST SLOPES CENTRAL MT CHAIN PERHAPS
INTO THE ERN PLAINS AFT 08Z...BUT FOR THE MOST PART CONFIDENCE TOO
LOW TO PLACE THIS DEGREE OF IMPACT IN ANY OF THE TAFS. OVER AND A
LITTLE WAYS EAST OF THE CONTINENTAL DIVIDE AFTER ABOUT 19Z
ISOLATED TO SCT HIGH BASED AND GUSTY SHRA AND TSRA ARE LIKELY TO
DEVELOP AND SOME MAY MAKE AS FAR EAST AS THE CENTRAL MT
CHAIN...INCLUDING ABQ...SAF AND LVS AFTER ROUGHLY 22Z. WHILE MOST
CIGS SHOULD REMAIN VFR...BRIEF AND VERY LOCALIZED MVFR
CONDITIONS...ALONG WITH MT OBSCURATIONS...COULD DEVELOP WITH
STRONGER TSRA.
43
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 79 48 75 36 / 5 5 5 5
DULCE........................... 72 38 70 28 / 30 20 30 10
CUBA............................ 71 41 71 32 / 40 40 20 5
GALLUP.......................... 78 43 73 31 / 5 10 0 0
EL MORRO........................ 72 38 68 30 / 30 20 0 0
GRANTS.......................... 76 39 74 32 / 30 20 5 5
QUEMADO......................... 75 42 72 37 / 20 10 0 0
GLENWOOD........................ 81 43 78 40 / 20 10 0 0
CHAMA........................... 66 37 64 27 / 30 30 40 10
LOS ALAMOS...................... 69 48 71 40 / 20 50 30 10
PECOS........................... 72 44 73 38 / 30 50 30 10
CERRO/QUESTA.................... 70 42 70 33 / 20 20 30 20
RED RIVER....................... 56 37 54 31 / 20 20 30 20
ANGEL FIRE...................... 64 33 64 28 / 20 40 30 20
TAOS............................ 70 41 70 32 / 20 40 30 10
MORA............................ 69 44 69 37 / 30 50 30 20
ESPANOLA........................ 76 50 76 39 / 20 50 20 10
SANTA FE........................ 71 47 71 40 / 20 50 30 10
SANTA FE AIRPORT................ 74 47 74 39 / 20 50 20 10
ALBUQUERQUE FOOTHILLS........... 77 55 78 46 / 10 50 20 5
ALBUQUERQUE HEIGHTS............. 79 52 81 46 / 10 50 10 5
ALBUQUERQUE VALLEY.............. 81 52 83 45 / 10 50 10 5
ALBUQUERQUE WEST MESA........... 80 52 82 45 / 10 50 10 5
LOS LUNAS....................... 80 51 82 45 / 10 50 10 5
RIO RANCHO...................... 79 53 80 45 / 10 50 10 5
SOCORRO......................... 80 52 84 47 / 10 30 10 5
SANDIA PARK/CEDAR CREST......... 72 49 73 42 / 20 50 20 5
TIJERAS......................... 76 50 76 43 / 20 50 20 5
MORIARTY/ESTANCIA............... 76 44 76 38 / 10 50 20 5
CLINES CORNERS.................. 73 44 73 39 / 20 40 30 10
GRAN QUIVIRA.................... 73 49 73 45 / 20 30 20 5
CARRIZOZO....................... 77 50 77 48 / 10 20 20 10
RUIDOSO......................... 71 46 71 45 / 30 20 30 10
CAPULIN......................... 70 48 72 40 / 20 20 20 20
RATON........................... 74 43 76 38 / 20 20 20 20
SPRINGER........................ 76 46 77 40 / 30 30 20 20
LAS VEGAS....................... 73 44 74 38 / 20 40 30 20
CLAYTON......................... 77 50 82 47 / 10 10 20 20
ROY............................. 73 48 77 43 / 20 30 20 20
CONCHAS......................... 81 54 85 51 / 10 20 20 20
SANTA ROSA...................... 80 51 83 50 / 10 20 20 20
TUCUMCARI....................... 82 52 87 51 / 5 10 20 10
CLOVIS.......................... 79 51 83 52 / 5 5 20 10
PORTALES........................ 79 52 83 54 / 5 5 20 10
FORT SUMNER..................... 79 52 84 51 / 5 10 20 10
ROSWELL......................... 83 53 87 52 / 10 10 20 10
PICACHO......................... 79 50 82 51 / 20 20 20 10
ELK............................. 74 48 75 48 / 20 30 20 10
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY EVENING
FOR THE FOLLOWING ZONES... NMZ101-105-106.
&&
$$
44
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
330 AM MDT FRI APR 22 2016
.SYNOPSIS...
MODEST MOISTURE CONTINUES TO WORK ITS WAY INTO CENTRAL NEW MEXICO
FROM THE SOUTHEAST AS A COUPLE OF LOW PRESSURE SYSTEMS CROSS THE
WEST COAST. THESE SYSTEMS WILL SKIRT AROUND NEW MEXICO TO THE
NORTH AND SOUTH...BUT THE MOISTURE IN PLACE WILL HELP SPARK
SCATTERED TO ISOLATED SHOWERS AND THUNDERSTORMS MAINLY OVER
CENTRAL AREAS THIS AFTERNOON AND EVENING...THEN ALONG AND TO A
LESSER EXTENT EAST OF THE CENTRAL MOUNTAIN CHAIN ON SATURDAY. THE
JET STREAM WILL MOVE OVER THE COLORADO AND NEW MEXICO BORDER ON
SATURDAY WITH SURFACE WIND GUSTS PROBABLY REACHING 50 MPH OVER A
GOOD PORTION OF NORTHERN NEW MEXICO IN THE AFTERNOON. FIRE WEATHER
CONCERNS WILL RAMP UP WEST OF THE CENTRAL MOUNTAIN CHAIN
SATURDAY...THEN CONTINUE TO PLAGUE PORTIONS OF NORTHERN AND
CENTRAL NEW MEXICO THROUGH TUESDAY AS DRIER AIR MOVES IN FROM THE
WEST AND BREEZY TO WINDY CONDITIONS RETURN DAILY.
&&
.DISCUSSION...
SOME STORMS WILL PRODUCE LITTLE OR NO RAIN WEST OF THE
CONTINENTAL DIVIDE TODAY...THEN AT LOWER ELEVATIONS BETWEEN THE
CENTRAL MOUNTAIN CHAIN AND CONTINENTAL DIVIDE ON SATURDAY.
MEANWHILE...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORM
SATURDAY AFTERNOON AND EVENING IN UNION COUNTY/FAR NE NM.
A PACIFIC COLD FRONT WILL CROSS FROM THE WEST SATURDAY AND
SATURDAY NIGHT USHERING COOLER TEMPERATURES AND DRY AIR FOR
SUNDAY. READINGS WILL VARY AROUND NORMAL MOST PLACES...EXCEPT ON
THE FAR EASTERN PLAINS WHERE READINGS 4 TO 10 DEGREES ABOVE NORMAL
SHOULD PERSIST. BREEZY TO WINDY CONDITIONS ARE EXPECTED TO RETURN
IN THE VICINITY OF THE I-40 CORRIDOR OF EASTERN NM SATURDAY
AFTERNOON WITH WESTERLY DOWNSLOPE FLOW.
ANOTHER UPPER LEVEL LOW PRESSURE SYSTEM WILL DIG INTO THE GREAT
BASIN ON MONDAY...THEN PASS NORTH OF NEW MEXICO ON TUESDAY
STEERING THE JET STREAM SQUARELY OVER THE FORECAST AREA. THIS WILL
KEEP BREEZY TO WINDY CONDITIONS IN THE FORECAST ACROSS WESTERN
AREAS MONDAY AND AREAWIDE TUESDAY. IT WILL CAUSE FIRE WEATHER
CONCERNS TO PERSIST.
SHORT WAVE RIDGING WILL CAUSE WINDS TO SETTLE DOWN WEDNESDAY...BUT
SW FLOW LOOKS TO STRENGTHEN AGAIN DURING THE LATTER HALF OF THE
WEEK AS YET ANOTHER UPPER LEVEL LOW PRESSURE SYSTEM DIGS INTO THE
GREAT BASIN AND APPROACHES NM FROM THE W OR NW.
44
&&
.FIRE WEATHER...
CRITICAL CONDITIONS WILL BE AT LEAST SPOTTY SATURDAY THROUGH MONDAY
WITH MORE WIDESPREAD CRITICAL CONDITIONS POSSIBLE NEXT TUESDAY. VENT
RATES WILL BE GOOD TO EXCELLENT TODAY THROUGH NEXT WEDNESDAY.
THE LATEST MODELS QUITE CONSISTENT WITH PREVIOUS VERSIONS IN THE
SHORTER TERM. THE UPPER RIDGE WILL BE MOVING OVER NEW MEXICO TODAY
AND THEN TO THE EAST OF THE STATE SATURDAY AS AN UPPER LOW TRACKS
INTO THE GREAT BASIN AND THROUGH THE CENTRAL ROCKIES. WINDS ALOFT
WILL TRANSITION TO SOUTHWEST LATER TODAY AND TONIGHT...AND WILL
STRENGTHEN WITH TIME. LOW LEVEL MOISTURE APPEARS TO BE MIGRATING INTO
SOUTH CENTRAL NM AT THIS TIME...AND A SUSTAINED SOUTHEAST TO SOUTH
FLOW REMAINS FORECAST...WHICH WOULD BRING HIGHER DEW POINTS UP THE
RGV AND TOWARDS THE CONTDVD...AS THE GFS HAS BEEN INDICATING FOR
SEVERAL DAYS. RUC AND HRRR NOW JUMPING ONBOARD BREAKING OUT CONVECTION
ALONG THE CONTDVD AND CENTRAL MT CHAIN BY MIDAFTERNOON. WITH THE
POOR RH RECOVERIES ALONG/WEST OF THE CONTDVD AT THIS TIME...CAN/T HELP BUT
THINK THERE MAY BE SOME HIGH BASED VIRGA SHOWERS/ISOLD DRY LIGHTNING
OVER THIS AREA LATER TODAY...GIVEN THE INSTABILITY FORECAST BY THE NAM12.
CONVECTION THIS EVENING MAY RESULT IN SOME WETTING PRECIPITATION BETWEEN THE
CONTDVD AND EAST SLOPES OF THE CENTRAL MT CHAIN.
SATURDAY STILL LOOKS TO SEE WIND GUSTS TO AROUND 45 OR 50 MPH AS THE
WESTERLY WINDS SHOVE THE LOW LEVEL MOISTURE FROM WEST TO EAST OVER
THE STATE. MIN RH VALUES FALL BELOW 15 PERCENT FOR PORTIONS OF THE
MIDDLE RGV AND WEST. DECIDED TO GO AHEAD WITH A FIRE WEATHER WATCH
FOR AREAS BELOW SNOWPACK FOR THE NORTHWEST/WEST CENTRAL AND MIDDLE RGV
ALTHOUGH MAINLY FOR BERNALILLO AND VALENCIA COUNTIES IF THE GRIDS
ARE CLOSE. NOT SURE OF THE STATE OF GREENUP AT THIS TIME...BUT RECENT
COOLER WEATHER MAY HAVE RETARDED IT. HIGHS WILL BE ABOVE AVERAGE...BUT
NOT OVERLY SO...IN THE RANGE OF 5 TO 10 DEGREES.
CONVECTION WILL BE FOCUSED OVER THE CENTRAL AND EAST SATURDAY/SATURDAY
NIGHT BUT SUNDAY LOOKS TO BE DRY. THERE MAY BE A FEW SHOWERS OR STORMS
ON THE DRIER SIDE FROM THE CENTRAL MT CHAIN WWD AS THE MOISTURE BECOMES
MORE SHALLOW ON SATURDAY. RIDGETOP WINDS MAY PERSIST SATURDAY NIGHT BEFORE
RELENTING SOMEWHAT SUNDAY UNDER ZONAL FLOW...BUT NOT ENOUGH TO
ELIMINATE THE POTENTIAL FOR CRITICAL CONDITIONS IN THE EAST CENTRAL
SUNDAY AFTERNOON. RH RECOVERIES SATURDAY AND SUNDAY NIGHT WILL BE
FAIR TO POOR FOR MANY LOCALES.
MONDAY THROUGH TUESDAY WILL SEE INCREASING WINDS AS ANOTHER SYSTEM
SWINGS THROUGH THE CENTRAL ROCKIES. POOR RH RECOVERIES LOOK TO BE
WIDESPREAD MONDAY NIGHT. HIGHS WILL FALL TO AROUND 5 TO 10 DEGREES
BELOW AVERAGE WEST AND CENTRAL AND TO NEAR AVERAGE EAST BY TUESDAY...
TO HELP MODERATE THE COMBO OF WIND AND SUB 15 PERCENT RH FROM THE
MIDDLE RGV TO THE EAST CENTRAL AND NORTHEAST PLAINS TUESDAY AFTERNOON...
WHERE CRITICAL CONDITIONS LOOK TO BE WIDESPREAD. ANY WETTING PRECIPITATION
WILL BE CONFINED TO THE HIGHER TERRAIN OF THE NORTHWEST AND NORTH CENTRAL
MONDAY THROUGH TUESDAY. GUSTY WEST WINDS MAY CONTINUE TUESDAY NIGHT BEFORE
SLACKING OFF. ANOTHER SYSTEM LINED UP FOR THE END OF NEXT WEEK BUT GFS
IS DRIER AND WINDIER...THE ECMWF IS WETTER.
&&
.AVIATION...
06Z TAF CYCLE
UPPER RIDGE ENTERING NM AT PRODUCT GENERATION TIME WILL MOVE OVER
THE STATE OVERNIGHT WITH FLOW ALOFT BECOMING SOUTHWEST LATER FRI.
BACK DOOR FRONT HAS BREACHED THE GAPS OF CENTRAL MT CHAIN AND WILL
CONTINUE TO GENERATE SPOTTY MODERATE E TO SE WINDS UNTIL NEAR OR A
LITTLE BEFORE DAWN. THIS UPSLOPE FLOW MAY STILL LEAD TO A FEW
PATCHES OF MVFR CIGS FROM THE EAST SLOPES CENTRAL MT CHAIN PERHAPS
INTO THE ERN PLAINS AFT 08Z...BUT FOR THE MOST PART CONFIDENCE TOO
LOW TO PLACE THIS DEGREE OF IMPACT IN ANY OF THE TAFS. OVER AND A
LITTLE WAYS EAST OF THE CONTINENTAL DIVIDE AFTER ABOUT 19Z
ISOLATED TO SCT HIGH BASED AND GUSTY SHRA AND TSRA ARE LIKELY TO
DEVELOP AND SOME MAY MAKE AS FAR EAST AS THE CENTRAL MT
CHAIN...INCLUDING ABQ...SAF AND LVS AFTER ROUGHLY 22Z. WHILE MOST
CIGS SHOULD REMAIN VFR...BRIEF AND VERY LOCALIZED MVFR
CONDITIONS...ALONG WITH MT OBSCURATIONS...COULD DEVELOP WITH
STRONGER TSRA.
43
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 79 48 75 36 / 5 5 5 5
DULCE........................... 72 38 70 28 / 30 20 30 10
CUBA............................ 71 41 71 32 / 40 40 20 5
GALLUP.......................... 78 43 73 31 / 5 10 0 0
EL MORRO........................ 72 38 68 30 / 30 20 0 0
GRANTS.......................... 76 39 74 32 / 30 20 5 5
QUEMADO......................... 75 42 72 37 / 20 10 0 0
GLENWOOD........................ 81 43 78 40 / 20 10 0 0
CHAMA........................... 66 37 64 27 / 30 30 40 10
LOS ALAMOS...................... 69 48 71 40 / 20 50 30 10
PECOS........................... 72 44 73 38 / 30 50 30 10
CERRO/QUESTA.................... 70 42 70 33 / 20 20 30 20
RED RIVER....................... 56 37 54 31 / 20 20 30 20
ANGEL FIRE...................... 64 33 64 28 / 20 40 30 20
TAOS............................ 70 41 70 32 / 20 40 30 10
MORA............................ 69 44 69 37 / 30 50 30 20
ESPANOLA........................ 76 50 76 39 / 20 50 20 10
SANTA FE........................ 71 47 71 40 / 20 50 30 10
SANTA FE AIRPORT................ 74 47 74 39 / 20 50 20 10
ALBUQUERQUE FOOTHILLS........... 77 55 78 46 / 10 50 20 5
ALBUQUERQUE HEIGHTS............. 79 52 81 46 / 10 50 10 5
ALBUQUERQUE VALLEY.............. 81 52 83 45 / 10 50 10 5
ALBUQUERQUE WEST MESA........... 80 52 82 45 / 10 50 10 5
LOS LUNAS....................... 80 51 82 45 / 10 50 10 5
RIO RANCHO...................... 79 53 80 45 / 10 50 10 5
SOCORRO......................... 80 52 84 47 / 10 30 10 5
SANDIA PARK/CEDAR CREST......... 72 49 73 42 / 20 50 20 5
TIJERAS......................... 76 50 76 43 / 20 50 20 5
MORIARTY/ESTANCIA............... 76 44 76 38 / 10 50 20 5
CLINES CORNERS.................. 73 44 73 39 / 20 40 30 10
GRAN QUIVIRA.................... 73 49 73 45 / 20 30 20 5
CARRIZOZO....................... 77 50 77 48 / 10 20 20 10
RUIDOSO......................... 71 46 71 45 / 30 20 30 10
CAPULIN......................... 70 48 72 40 / 20 20 20 20
RATON........................... 74 43 76 38 / 20 20 20 20
SPRINGER........................ 76 46 77 40 / 30 30 20 20
LAS VEGAS....................... 73 44 74 38 / 20 40 30 20
CLAYTON......................... 77 50 82 47 / 10 10 20 20
ROY............................. 73 48 77 43 / 20 30 20 20
CONCHAS......................... 81 54 85 51 / 10 20 20 20
SANTA ROSA...................... 80 51 83 50 / 10 20 20 20
TUCUMCARI....................... 82 52 87 51 / 5 10 20 10
CLOVIS.......................... 79 51 83 52 / 5 5 20 10
PORTALES........................ 79 52 83 54 / 5 5 20 10
FORT SUMNER..................... 79 52 84 51 / 5 10 20 10
ROSWELL......................... 83 53 87 52 / 10 10 20 10
PICACHO......................... 79 50 82 51 / 20 20 20 10
ELK............................. 74 48 75 48 / 20 30 20 10
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY EVENING
FOR THE FOLLOWING ZONES... NMZ101-105-106.
&&
$$
44
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1240 PM EDT FRI APR 22 2016
.SYNOPSIS...A COLD FRONT WILL MOVE SLOWLY EAST ACROSS CENTRAL NC
LATE TONIGHT THROUGH EARLY SATURDAY MORNING. HIGH PRESSURE WILL
BUILD INTO THE REGION BEHIND THE FRONT SATURDAY AFTERNOON
THROUGH SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM FRIDAY...
MAIN ADJUSTMENTS THIS MORNING WERE TO RAISE POPS WHERE STEADY
SHOWERS ARE ONGOING OR IMMINENT. INCREASINGLY WARM AND MOIST SSW LOW
LEVEL FLOW IS PULLING ABOVE NORMAL PW INTO THE AREA (NEAR 1.5")...
AND DEEPENING FORCING FOR ASCENT (INCLUDING MODEST MID LEVEL
HEIGHT FALLS AND IMPROVING UPPER DIVERGENCE) AND MINOR INSTABILITY
WITH MIXING/HEATING WILL LEAD TO FURTHER DEVELOPMENT OF SHOWERS AND
ISOLATED STORMS THROUGH THE AFTERNOON... YIELDING SEVERAL HOURS OF
CATEGORICAL POPS AREAWIDE. WHILE QPF FROM THE CAMS STILL APPEARS
OVERDONE IN SPOTS... THE OVERALL TOTAL QPF APPEARS TO BE TRENDING A
BIT HIGHER THAN WAS DENOTED YESTERDAY... WITH OBSERVATIONS
INDICATING A QUARTER TO HALF INCH FOR MOST AREAS THROUGH TONIGHT
WITH LOCALLY HIGHER AMOUNTS. THE RISK OF THUNDER APPEARS MARGINAL
WITH RAP SURFACE CAPE PEAKING AT 200-500 J/KG NW TO SE... ALTHOUGH
DEEP LAYER SHEAR SHOULD BE IMPROVING IN THE EAST. WILL LEAVE IN A
MENTION OF ISOLATED THUNDER AREAWIDE... AND MONITOR CLOSELY FOR ANY
AREAS OF ENHANCED HEATING THAT MIGHT PUSH CAPE UP. OBSERVED TRENDS
AND HIGH RES GUIDANCE SHOW A SMALL TEMP CLIMB TODAY GIVEN THE CLOUDS
AND PRECIP... SO EXPECT HIGHS OF 69-78 NW TO SE. -GIH
EARLIER DISCUSSION FROM 335 AM: WATER VAPOR IMAGERY AT 07Z DEPICTS
WELL DEFINED S/W LIFTING E-NE OUT OF THE LOWER MS VALLEY. NEAR TERM
MODEL GUIDANCE HAS DECENT HANDLE ON THIS FEATURE...LIFTING IT ACROSS
OUR REGION LATER TODAY. THE APPROACH OF THIS SYSTEM INTERACTING WITH
AVAILABLE MOISTURE WILL TRIGGER SCATTERED-NUMEROUS
SHOWERS...INITIALLY OVER THE WESTERN PIEDMONT AFTER 9-10AM...AND
ACROSS THE BULK OF CENTRAL THIS AFTERNOON. MODEL GUIDANCE HAS
TRENDED DEEPER WITH THE LIFT THROUGH THE COLUMN...SUPPORTIVE OF
HIGHER RAINFALL AMOUNTS THAN SUGGESTED A COUPLE OF DAYS AGO. NOT
READY TO CLIMB ONBOARD THE GUIDANCE FROM WPC...SUGGESTING RAINFALL
TOTALS IN THE RDU AREA 1-1.33 INCHES TODAY AND TONIGHT. HAVE LEANED
TOWARD AMOUNTS GENERALLY IN THE HALF TO THREE-QUARTERS OF AN INCH
WITH POCKETS AROUND AN INCH. RAIN WILL BE WELCOMED FOR MOST FOLKS AS
MEASURABLE RAINFALL HAS NOT BEEN OBSERVED IN 8-9 DAYS. THUNDER
THREAT STILL APPEARS CONFINED TO AREAS ALONG AND EAST OF HIGHWAY 1
DURING PEAK HEATING THOUGH LOW LEVEL INSTABILITY MEAGER WITH SBCAPE
NO WORSE THAN A 1000-1200 J/KG AND MLCAPE AT OR BELOW 300 J/KG.0-6KM
BULK SHEAR INCREASES THIS AFTERNOON TO AROUND 35 KTS...SO EXPECT THE
SMATTERING OF SHOWERS THIS MORNING TO EVENTUALLY ORGANIZED INTO
BROKEN BAND OF SHOWERS BY MID AFTERNOON.
MAX TEMPS TODAY HIGHLY DEPENDENT UPON WHEN SHOWER COVERAGE
INCREASES. A DELAY IN THE ARRIVAL OF SHOWERS AT ANY ONE SPOT WILL
TRANSLATE TO WARMER HIGH TEMPS. USED A BLEND OF MOS
GUIDANCE...YIELDING MAX TEMPS LOWER 70S NW TO MID-UPPER 70S EAST-SE.
TONIGHT...MAY SEE A TEMPORARY LULL IN SHOWER COVERAGE DEVELOP LATE
IN THE DAY/EARLY EVENING AS S/W TRAVERSES ACROSS THE REGION. EXPECT
TO SEE AN UPTICK IN SHOWER COVERAGE AFTER SUNSET AS SFC COLD FRONT
ASSOCIATED WITH THE NORTHERN STREAM S/W APPROACHES/CROSSES OUR
REGION. THIS BAND OF SHOWERS SHOULD EXIT THE PIEDMONT AROUND OR
SHORTLY AFTER MIDNIGHT...AND THE COASTAL PLAIN COUNTIES PRIOR TO
DAYBREAK SATURDAY. EXPECT PARTIAL CLEARING BEHIND THE EXITING FRONT
THOUGH RESIDUAL LOW LEVEL MOISTURE COUPLED WITH A LIGHT WIND REGIME
SUGGEST A GOOD POTENTIAL FOR LOW CLOUDS TO DEVELOP ACROSS THE AREA
OVERNIGHT. MIN TEMPS MID-UPPER 50S NW-LOWER 60S SE.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 350 AM FRIDAY...
NORTHERN STREAM S/W CROSSES OVERHEAD SATURDAY. WHILE MOISTURE
BASICALLY CONFINED TO THE LOWEST 10K FEET...MID LEVEL LAPSE RATES
BETWEEN 6 AND 6.5 C/KM ALONG WITH HEATING SHOULD TRIGGER A FEW LOW
TOPPED SHOWERS IN THE LATE MORNING AND AFTERNOON HOURS. EXPECT
HIGHEST RISK FOR SHOWERS (1:4 CHANCE) OVER THE FAR NE PIEDMONT AND
THE COASTAL PLAIN. SHOWER THREAT SHOULD DIMINISH/END PRIOR TO
SUNSET.
EARLY MORNING LOW CLOUDS SHOULD LIFT INTO A SCATTERED/BROKEN DECK BY
LATE MORNING. THE PARTIAL SUNSHINE AND A RELATIVELY MILD START TO
THE DAY SHOULD ALLOW TEMPS TO RECOVER INTO THE MID-UPPER
70S...WARMEST IN THE SW WHERE MORE SUN/FEWER (IF ANY) SHOWERS
EXPECTED.
HIGH PRESSURE OVER SOUTHERN SECTIONS OF ONTARIO/QUEBEC BUILDS SWD
INTO THE SOUTHERN APPALACHIANS SATURDAY NIGHT. THIS WILL LEAD TO
CLEARING SKIES AND SLIGHTLY COOLER TEMPS. MIN TEMPS BY EARLY SUNDAY
50-55 DEGREES.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 305 AM FRIDAY...
SUNDAY THROUGH MONDAY NIGHT: MID LEVEL RIDGING WILL BUILD BACK OVER
THE AREA FOR THE SECOND HALF OF THE WEEKEND INTO EARLY NEXT WEEK.
MEANWHILE SURFACE HIGH PRESSURE... INITIALLY LOCATED OVER THE REGION
TO START THE PERIOD WILL SHIFT TO THE COAST AND THEN OFFSHORE SUNDAY
EVENING INTO EARLY NEXT WEEK. THIS WILL RESULT IN A DRY AND WARMING
FORECAST FOR THIS TIME FRAME. HIGHS SUNDAY ARE EXPECTED TO RANGE
FROM THE LOWER 70S NE TO THE UPPER 70S SW. HIGHS MONDAY SHOULD BE A
COUPLE OF CATEGORIES WARMER WITH A SOUTHERLY RETURN FLOW AROUND
OFFSHORE HIGH PRESSURE. THUS... EXPECT HIGHS ON MONDAY WILL BE IN
THE LOWER TO MID 80S. LOWS WILL FOLLOW A SIMILAR TREND... INCREASING
EACH MORNING. LOWS ARE EXPECTED TO BE IN 50S FOR MONDAY MONDAY
MORNING... AND NEAR 60/LOWER 60S ON TUESDAY MORNING.
TUESDAY THROUGH THURSDAY: THE MID LEVEL RIDGE WILL HAVE FLATTENED BY
TUESDAY MORNING AS A S/W DISTURBANCE TRACKS EASTWARD ACROSS THE
GREAT LAKES AND NORTHEAST U.S. MONDAY NIGHT INTO TUESDAY. HOW THIS
SYSTEM INTERACTS WITH THE EASTERN CANADA DEEP MID/UPPER LEVEL LOW
WILL PLAY A ROLE ON HOW FAR SOUTH THE ASSOCIATED COLD FRONT (FROM
THE S/W TRACKING EAST ACROSS THE NORTHEASTERN U.S.) MEDIUM RANGE
MODELS HAVE STRUGGLED WITH HOW FAR SOUTH THE FRONT WILL MAKE IT NEXT
WEEK. THE 00Z/22ND GFS CONTINUES TO DRIVE THE FRONT SOUTHWARD
THROUGH THE AREA TUESDAY NIGHT INTO WEDNESDAY... WHILE THE 00Z/22ND
ECMWF STALLS THE FRONT JUST TO OUR NORTH AND NORTHEAST. THUS...
CONFIDENCE REMAINS LOW FOR TEMPS TUESDAY NIGHT ONWARD AND PRECIP
CHANCES FOR TUESDAY EVENING INTO WEDNESDAY. FOR NOW WILL GO WITH
ONLY A SLIGHT CHANCE OF SHOWERS AND STORMS FROM LATE TUESDAY THROUGH
WEDNESDAY. TEMPS WILL BE GREATLY DEPENDENT BY THE PLACEMENT OF THE
FRONT... WITH LIKELY A LARGE TEMPERATURE GRADIENT NEAR THE FRONT.
REGARDLESS THOUGH... TUESDAY LOOKS TO BE WARM... WITH HIGHS IN THE
MID TO UPPER 80S. WILL FOLLOW CLOSE TO WPC AND GO WITH HIGHS
WEDNESDAY RANGING FROM THE UPPER 70S NE TO UPPER 80S SW... WITH THE
COLD FRONT BISECTING THE AREA ON WEDNESDAY MORNING. LOWS ARE
EXPECTED TO RANGE FROM THE MID TO UPPER 50S TO THE LOWER 60S.
THE NEXT COLD FRONT IS EXPECTED TO APPROACH THE AREA ON THURSDAY WITH
INCREASING CHANCES FOR SHOWERS AND STORMS... WITH HIGHS NEAR 80
NORTH TO THE MID TO UPPER 80S SOUTH... WITH THE STALLED FRONT
EXPECTED TO BE TO THE NORTH OF THE AREA BY THURSDAY.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 1240 PM FRIDAY...
DIFFICULT AVIATION FORECAST AS ROUNDS OF SHOWERS AND ISOLATED STORMS
WILL LEAD TO WIDELY VARYING CIGS/VSBYS FOR THE NEXT 12-15 HOURS. A
WARM MOIST FLOW FROM THE SW ALONG WITH AN APPROACHING COLD FRONT AND
UPPER LEVEL DISTURBANCE WILL GENERATE INCREASING COVERAGE OF SHOWERS
AT ALL TERMINALS THROUGH THIS AFTERNOON. IFR TO LOW-END MVFR CIGS
BETWEEN 500 AND 1500 FT AGL ARE LIKELY WITHIN THE MODERATE TO HEAVY
SHOWERS WITH IFR VSBYS... AND WHEN RAIN IS LIGHT OR ABSENT... THE
LOWER CLOUDS WILL BECOME SCATTERED WITH VFR CIGS ABOVE 4KFT AGL AND
MVFR-VFR VSBYS. THE BEST CHANCE FOR DOMINANT SUB-VFR CONDITIONS ARE
18-22Z AND 01Z-05Z AT RDU/FAY/RWI... AND 22Z-02Z AT INT/GSO. A
THUNDERSTORM IS POSSIBLE THIS AFTERNOON... MAINLY AT RDU/FAY/RWI.
THE SHOWERS WILL BE ON A DIMINISHING TREND IN COVERAGE AND INTENSITY
FROM WEST TO EAST LATER THIS EVENING INTO THE OVERNIGHT HOURS (03Z-
08Z)... BUT WITH LIGHT SURFACE WINDS AND HIGH HUMIDITY LINGERING
OVER CENTRAL NC AHEAD OF THE COLD FRONT... LOWER CIGS (AGAIN IN THE
500-1500 AGL RANGE) IN THE FORM OF BROKEN SHALLOW STRATUS CLOUDS ARE
LIKELY TO RE-DEVELOP TONIGHT AS THE RAIN TAPERS DOWN... AND ISOLATED
POCKETS OF MVFR-IFR VSBYS ARE POSSIBLE AS WELL. THESE LOW CLOUDS
WILL DISPERSE AND LIFT... LEADING TO VFR-DOMINANT CONDITIONS
AT ALL SITES AFTER 14Z SAT.
LOOKING BEYOND 18Z SAT... A FEW SHOWERS ARE POSSIBLE ESPECIALLY AT
NORTHERN TERMINALS SAT AFTERNOON BUT ANY SUB-VFR CONDITIONS WOULD BE
VERY BRIEF. OTHERWISE... THE COLD FRONT WILL FINALLY DROP SE THROUGH
THE AREA SAT NIGHT WITH HIGH PRESSURE BUILDING INTO AND OVER THE
AREA SUN/MON BEFORE SHIFTING OFFSHORE THROUGH MIDWEEK... LEADING TO
VFR CONDITIONS AND A WARMING TREND SUN INTO TUE. AN APPROACHING
BACKDOOR FRONT MAY BRING A FEW SHOWERS TO NORTHERN TERMINALS TUE
NIGHT/WED BUT VFR CONDITIONS SHOULD STILL PREVAIL. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS/HARTFIELD
NEAR TERM...HARTFIELD/WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1033 AM EDT FRI APR 22 2016
.SYNOPSIS...A COLD FRONT WILL MOVE SLOWLY EAST ACROSS CENTRAL NC
LATE TONIGHT THROUGH EARLY SATURDAY MORNING. HIGH PRESSURE WILL
BUILD INTO THE REGION BEHIND THE FRONT SATURDAY AFTERNOON
THROUGH SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM FRIDAY...
MAIN ADJUSTMENTS THIS MORNING WERE TO RAISE POPS WHERE STEADY
SHOWERS ARE ONGOING OR IMMINENT. INCREASINGLY WARM AND MOIST SSW LOW
LEVEL FLOW IS PULLING ABOVE NORMAL PW INTO THE AREA (NEAR 1.5")...
AND DEEPENING FORCING FOR ASCENT (INCLUDING MODEST MID LEVEL
HEIGHTFALLS AND IMPROVING UPPER DIVERGENCE) AND MINOR INSTABILITY
WITH MIXING/HEATING WILL LEAD TO FURTHER DEVELOPMENT OF SHOWERS AND
ISOLATED STORMS THROUGH THE AFTERNOON... YIELDING SEVERAL HOURS OF
CATEGORICAL POPS AREAWIDE. WHILE QPF FROM THE CAMS STILL APPEARS
OVERDONE IN SPOTS... THE OVERALL TOTAL QPF APPEARS TO BE TRENDING A
BIT HIGHER THAN WAS DENOTED YESTERDAY... WITH OBSERVATIONS
INDICATING A QUARTER TO HALF INCH FOR MOST AREAS THROUGH TONIGHT
WITH LOCALLY HIGHER AMOUNTS. THE RISK OF THUNDER APPEARS MARGINAL
WITH RAP SURFACE CAPE PEAKING AT 200-500 J/KG NW TO SE... ALTHOUGH
DEEP LAYER SHEAR SHOULD BE IMPROVING IN THE EAST. WILL LEAVE IN A
MENTION OF ISOLATED THUNDER AREAWIDE... AND MONITOR CLOSELY FOR ANY
AREAS OF ENHANCED HEATING THAT MIGHT PUSH CAPE UP. OBSERVED TRENDS
AND HIGH RES GUIDANCE SHOW A SMALL TEMP CLIMB TODAY GIVEN THE CLOUDS
AND PRECIP... SO EXPECT HIGHS OF 69-78 NW TO SE. -GIH
EARLIER DISCUSSION FROM 335 AM: WATER VAPOR IMAGERY AT 07Z DEPICTS
WELL DEFINED S/W LIFTING E-NE OUT OF THE LOWER MS VALLEY. NEAR TERM
MODEL GUIDANCE HAS DECENT HANDLE ON THIS FEATURE...LIFTING IT ACROSS
OUR REGION LATER TODAY. THE APPROACH OF THIS SYSTEM INTERACTING WITH
AVAILABLE MOISTURE WILL TRIGGER SCATTERED-NUMEROUS
SHOWERS...INITIALLY OVER THE WESTERN PIEDMONT AFTER 9-10AM...AND
ACROSS THE BULK OF CENTRAL THIS AFTERNOON. MODEL GUIDANCE HAS
TRENDED DEEPER WITH THE LIFT THROUGH THE COLUMN...SUPPORTIVE OF
HIGHER RAINFALL AMOUNTS THAN SUGGESTED A COUPLE OF DAYS AGO. NOT
READY TO CLIMB ONBOARD THE GUIDANCE FROM WPC...SUGGESTING RAINFALL
TOTALS IN THE RDU AREA 1-1.33 INCHES TODAY AND TONIGHT. HAVE LEANED
TOWARD AMOUNTS GENERALLY IN THE HALF TO THREE-QUARTERS OF AN INCH
WITH POCKETS AROUND AN INCH. RAIN WILL BE WELCOMED FOR MOST FOLKS AS
MEASURABLE RAINFALL HAS NOT BEEN OBSERVED IN 8-9 DAYS. THUNDER
THREAT STILL APPEARS CONFINED TO AREAS ALONG AND EAST OF HIGHWAY 1
DURING PEAK HEATING THOUGH LOW LEVEL INSTABILITY MEAGER WITH SBCAPE
NO WORSE THAN A 1000-1200 J/KG AND MLCAPE AT OR BELOW 300 J/KG.0-6KM
BULK SHEAR INCREASES THIS AFTERNOON TO AROUND 35 KTS...SO EXPECT THE
SMATTERING OF SHOWERS THIS MORNING TO EVENTUALLY ORGANIZED INTO
BROKEN BAND OF SHOWERS BY MID AFTERNOON.
MAX TEMPS TODAY HIGHLY DEPENDENT UPON WHEN SHOWER COVERAGE
INCREASES. A DELAY IN THE ARRIVAL OF SHOWERS AT ANY ONE SPOT WILL
TRANSLATE TO WARMER HIGH TEMPS. USED A BLEND OF MOS
GUIDANCE...YIELDING MAX TEMPS LOWER 70S NW TO MID-UPPER 70S EAST-SE.
TONIGHT...MAY SEE A TEMPORARY LULL IN SHOWER COVERAGE DEVELOP LATE
IN THE DAY/EARLY EVENING AS S/W TRAVERSES ACROSS THE REGION. EXPECT
TO SEE AN UPTICK IN SHOWER COVERAGE AFTER SUNSET AS SFC COLD FRONT
ASSOCIATED WITH THE NORTHERN STREAM S/W APPROACHES/CROSSES OUR
REGION. THIS BAND OF SHOWERS SHOULD EXIT THE PIEDMONT AROUND OR
SHORTLY AFTER MIDNIGHT...AND THE COASTAL PLAIN COUNTIES PRIOR TO
DAYBREAK SATURDAY. EXPECT PARTIAL CLEARING BEHIND THE EXITING FRONT
THOUGH RESIDUAL LOW LEVEL MOISTURE COUPLED WITH A LIGHT WIND REGIME
SUGGEST A GOOD POTENTIAL FOR LOW CLOUDS TO DEVELOP ACROSS THE AREA
OVERNIGHT. MIN TEMPS MID-UPPER 50S NW-LOWER 60S SE.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 350 AM FRIDAY...
NORTHERN STREAM S/W CROSSES OVERHEAD SATURDAY. WHILE MOISTURE
BASICALLY CONFINED TO THE LOWEST 10K FEET...MID LEVEL LAPSE RATES
BETWEEN 6 AND 6.5 C/KM ALONG WITH HEATING SHOULD TRIGGER A FEW LOW
TOPPED SHOWERS IN THE LATE MORNING AND AFTERNOON HOURS. EXPECT
HIGHEST RISK FOR SHOWERS (1:4 CHANCE) OVER THE FAR NE PIEDMONT AND
THE COASTAL PLAIN. SHOWER THREAT SHOULD DIMINISH/END PRIOR TO
SUNSET.
EARLY MORNING LOW CLOUDS SHOULD LIFT INTO A SCATTERED/BROKEN DECK BY
LATE MORNING. THE PARTIAL SUNSHINE AND A RELATIVELY MILD START TO
THE DAY SHOULD ALLOW TEMPS TO RECOVER INTO THE MID-UPPER
70S...WARMEST IN THE SW WHERE MORE SUN/FEWER (IF ANY) SHOWERS
EXPECTED.
HIGH PRESSURE OVER SOUTHERN SECTIONS OF ONTARIO/QUEBEC BUILDS SWD
INTO THE SOUTHERN APPALACHIANS SATURDAY NIGHT. THIS WILL LEAD TO
CLEARING SKIES AND SLIGHTLY COOLER TEMPS. MIN TEMPS BY EARLY SUNDAY
50-55 DEGREES.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 305 AM FRIDAY...
SUNDAY THROUGH MONDAY NIGHT: MID LEVEL RIDGING WILL BUILD BACK OVER
THE AREA FOR THE SECOND HALF OF THE WEEKEND INTO EARLY NEXT WEEK.
MEANWHILE SURFACE HIGH PRESSURE... INITIALLY LOCATED OVER THE REGION
TO START THE PERIOD WILL SHIFT TO THE COAST AND THEN OFFSHORE SUNDAY
EVENING INTO EARLY NEXT WEEK. THIS WILL RESULT IN A DRY AND WARMING
FORECAST FOR THIS TIME FRAME. HIGHS SUNDAY ARE EXPECTED TO RANGE
FROM THE LOWER 70S NE TO THE UPPER 70S SW. HIGHS MONDAY SHOULD BE A
COUPLE OF CATEGORIES WARMER WITH A SOUTHERLY RETURN FLOW AROUND
OFFSHORE HIGH PRESSURE. THUS... EXPECT HIGHS ON MONDAY WILL BE IN
THE LOWER TO MID 80S. LOWS WILL FOLLOW A SIMILAR TREND... INCREASING
EACH MORNING. LOWS ARE EXPECTED TO BE IN 50S FOR MONDAY MONDAY
MORNING... AND NEAR 60/LOWER 60S ON TUESDAY MORNING.
TUESDAY THROUGH THURSDAY: THE MID LEVEL RIDGE WILL HAVE FLATTENED BY
TUESDAY MORNING AS A S/W DISTURBANCE TRACKS EASTWARD ACROSS THE
GREAT LAKES AND NORTHEAST U.S. MONDAY NIGHT INTO TUESDAY. HOW THIS
SYSTEM INTERACTS WITH THE EASTERN CANADA DEEP MID/UPPER LEVEL LOW
WILL PLAY A ROLE ON HOW FAR SOUTH THE ASSOCIATED COLD FRONT (FROM
THE S/W TRACKING EAST ACROSS THE NORTHEASTERN U.S.) MEDIUM RANGE
MODELS HAVE STRUGGLED WITH HOW FAR SOUTH THE FRONT WILL MAKE IT NEXT
WEEK. THE 00Z/22ND GFS CONTINUES TO DRIVE THE FRONT SOUTHWARD
THROUGH THE AREA TUESDAY NIGHT INTO WEDNESDAY... WHILE THE 00Z/22ND
ECMWF STALLS THE FRONT JUST TO OUR NORTH AND NORTHEAST. THUS...
CONFIDENCE REMAINS LOW FOR TEMPS TUESDAY NIGHT ONWARD AND PRECIP
CHANCES FOR TUESDAY EVENING INTO WEDNESDAY. FOR NOW WILL GO WITH
ONLY A SLIGHT CHANCE OF SHOWERS AND STORMS FROM LATE TUESDAY THROUGH
WEDNESDAY. TEMPS WILL BE GREATLY DEPENDENT BY THE PLACEMENT OF THE
FRONT... WITH LIKELY A LARGE TEMPERATURE GRADIENT NEAR THE FRONT.
REGARDLESS THOUGH... TUESDAY LOOKS TO BE WARM... WITH HIGHS IN THE
MID TO UPPER 80S. WILL FOLLOW CLOSE TO WPC AND GO WITH HIGHS
WEDNESDAY RANGING FROM THE UPPER 70S NE TO UPPER 80S SW... WITH THE
COLD FRONT BISECTING THE AREA ON WEDNESDAY MORNING. LOWS ARE
EXPECTED TO RANGE FROM THE MID TO UPPER 50S TO THE LOWER 60S.
THE NEXT COLD FRONT IS EXPECTED TO APPROACH THE AREA ON THURSDAY WITH
INCREASING CHANCES FOR SHOWERS AND STORMS... WITH HIGHS NEAR 80
NORTH TO THE MID TO UPPER 80S SOUTH... WITH THE STALLED FRONT
EXPECTED TO BE TO THE NORTH OF THE AREA BY THURSDAY.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 805 AM FRIDAY...
AVIATION CONDITIONS HAVE DETERIORATED TO MVFR WITH CEILINGS IN THE
1000-2500FT ALONG WITH POCKETS OF IFR 600-900FT CEILINGS. THE LOW
CEILINGS WILL PERSIST THROUGH 14Z-15Z THEN LIFT TO 2500-4000FT BY
EARLY AFTERNOON. SCATTERED SHOWERS AND ASSOCIATED MVFR VISIBILITIES
WILL CROSS THE TRIAD TERMINALS THROUGH 16Z SCATTERED TO NUMEROUS
SHOWERS WILL BECOME PROMINENT ACROSS THE REMAINDER OF CENTRAL NC
DURING THE AFTERNOON HOURS...PERSISTING INTO THE EVENING. FOR
NOW...THE THREAT FOR THUNDER APPEARS GREATEST IN VICINITY OF KFAY
AND KRWI DURING THE LATE AFTERNOON-EARLY EVENING HOURS WHEN LOW
LEVEL INSTABILITY IS AT ITS PEAK.
A SFC COLD FRONT WILL APPROACH FROM THE WEST TODAY...AND CROSS
CENTRAL NC LATE TONIGHT THROUGH EARLY SATURDAY MORNING. WITH THE
PASSAGE OF THE FRONT...THE NEAR SFC FLOW WILL VEER TO A WEST-NW
DIRECTION AND THE SHOWER THREAT WILL END. RESIDUAL LOW LEVEL
MOISTURE WILL LEAD TO THE FORMATION OF LOW CLOUDS LATE TONIGHT...
LINGERING INTO THE FIRST HALF OF SATURDAY MORNING. ONCE THESE CLOUDS
LIFT/DISSIPATE...VFR CONDITIONS ARE HIGHLY LIKELY FROM MID DAY
SATURDAY THROUGH MONDAY. A COLD FRONT APPROACHING FROM THE NORTH
TUESDAY WILL BRING THE NEXT THREAT FOR SUB VFR CONDITIONS TO CENTRAL
NC.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS/HARTFIELD
NEAR TERM...HARTFIELD/WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
923 PM CDT SAT APR 23 2016
.UPDATE...
ISSUED AT 921 PM CDT SAT APR 23 2016
WIDELY SCATTERED SHOWERS NORTHEAST DECREASING. SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS APPROACHING THE SOUTHWEST. EXPECT
AROUND OR SHORTLY AFTER MIDNIGHT. CONTINUED BREEZY TO WINDY.
UPDATE ISSUED AT 636 PM CDT SAT APR 23 2016
DEEP LOW PRESSURE OVER WESTERN SOUTH DAKOTA AND HIGH PRESSURE
ACROSS MANITOBA WERE ENHANCING THE LOW LEVEL WINDS ACROSS NORTH
DAKOTA. MOST AREAS HAD EAST WINDS OF 20 TO 35 MPH WITH A FEW
SITES ABOVE 40 MPH. EXPECT THE WINDS TO CONTINUE TONIGHT. WATER
VAPOR CHANNEL SHOWS THE 700 MB UPPER LOW IN THE VICINITY OF WEST
CENTRAL WYOMING. SCATTERED THUNDERSTORMS HAVE DEVELOPED INTO SOUTH
CENTRAL MONTANA SOUTHEAST THROUGH EASTERN WYOMING. EXPECT THIS
AREA TO ROTATE NORTHEAST INTO SOUTHWEST NORTH DAKOTA LATE TONIGHT.
OTHERWISE FOR THE NEXT 6 HOURS OR SO LOOKING AT SOME INCREASING
CLOUDS AND A STEADY EAST WIND OF 20 TO 40 MPH.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 313 PM CDT SAT APR 23 2016
MAIN HIGHLIGHTS THROUGH SUNDAY AFTERNOON: RAINFALL AMOUNTS
ESPECIALLY LOCATIONS WHERE TOTALS EXCEED ONE INCH...A FEW STRONG
THUNDERSTORMS SOUTHWEST TONIGHT WITH POSSIBLE SMALL HAIL AND
GUSTY WINDS...AND POTENTIAL WIND ADVISORY TURTLE MOUNTAINS AND
VICINITY SUNDAY.
THE LATEST WATER VAPOR IMAGERY SHOWS A CLOSED UPPER LOW CIRCULATING
OVER FAR SOUTHEAST IDAHO WITH A DEEPENING SURFACE LOW
DOWNSTREAM...POSITIONED OVER NORTHEAST WYOMING. A WARM FRONT
EXTENDED FROM THIS LOW AND WAS DRAPED ALONG THE SOUTHERN BORDER.
WITH THIS WARM FRONT REMAINING JUST SOUTH OF OUR BORDER
TONIGHT/SUNDAY...AND THE UPPER LOW CATCHING UP WITH THE SURFACE
LOW AND BECOMING A VERTICALLY STACKED SYSTEM OVER CENTRAL SOUTH
DAKOTA...A WELL DEFINED DEFORMATION ZONE SETS UP OVER ALL OF
CENTRAL AND SOUTHERN NORTH DAKOTA LATER TONIGHT THROUGH SUNDAY.
FORCING/VERTICAL MOTION PER Q-VECTOR DIVERGENCE FIELD AND STEEP
MID LEVEL LAPSE RATES APPEAR MAXIMIZED BETWEEN INTERSTATE 94 AND
JUST SOUTH OF HIGHWAY 2. THIS SHOULD SET THE STAGE FOR PERIODS OF
HEAVIER RAINFALL AND HIGHEST RAINFALL TOTALS THROUGH SUNDAY.
EXPECT BETWEEN 1 AND 1.4 INCHES OF TOTAL RAINFALL THROUGH SUNDAY
NIGHT BETWEEN INTERSTATE 94 AND HIGHWAY 2.
THUNDERSTORM POTENTIAL REMAINS ELEVATED THROUGH THE PERIOD WITH
DECREASING CIN AS MOISTURE INCREASES THROUGH THE COLUMN AND
STEEPENING MID LEVEL LAPSE RATES. BEST CHANCES WILL BE TONIGHT
THROUGH SUNDAY MORNING...WITH SOUNDINGS BECOMING SATURATED AND
SHOWING RELATIVELY SKINNY OR NO CAPE FIELD. ENVIRONMENT SHOULD
TRANSITION MORE TOWARDS A HEAVY RAIN VERSUS CONVECTIVE IN NATURE.
SPC HAS MAINTAINED THE MARGINAL RISK FOR SEVERE THUNDERSTORMS IN
THE FAR SOUTHWEST TONIGHT. THINKING IS CONVECTION WOULD BEGIN AFTER
03Z PER LATEST HRRR AND GRADUALLY INCREASE OVERNIGHT INTO MID
MORNING SUNDAY.
GUSTY NORTHEAST WINDS WILL CONTINUE TONIGHT THROUGH SUNDAY ACROSS
ALL OF WESTERN AND CENTRAL NORTH DAKOTA. THE STRONGEST WINDS ARE
FORECAST ALONG AND NORTH OF HIGHWAY 2...WITH THE TURTLE MOUNTAINS
PINPOINTED FOR THE HIGHEST SUSTAINED WINDS OF AROUND 30 MPH AND
GUSTS TO 45 MPH. FUTURE SHIFTS CAN RE-EVALUATE FOR A POSSIBLE WIND
ADVISORY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 313 PM CDT SAT APR 23 2016
THE VERTICALLY STACKED SYSTEM CONTINUES TO SLOWLY SHIFT EAST
SUNDAY NIGHT AND MONDAY WITH A GRADUAL DECREASE IN POPS. HOWEVER
THE ECMWF HAS BEEN CONSISTENTLY ADVERTISING HIGHER QPF AND COLDER
AIR ESPECIALLY ALONG AND SOUTH OF INTERSTATE 94 MONDAY. THUS HAVE
TRENDED POPS BETWEEN CHC/LIKELY WITH MOSTLY RAIN AND A LITTLE BIT
OF SNOW EXPECTED. SNOWFALL ACCUMULATIONS OF A COUPLE TENTHS POSSIBLE
SUNDAY NIGHT ACROSS THE WEST.
ANOTHER ROUND OF PRECIPITATION IS POSSIBLE TUESDAY NIGHT THROUGH
WEDNESDAY NIGHT MAINLY ACROSS SOUTHERN NORTH DAKOTA. THE GFS AND
ECMWF CONTINUE TO BE AT ODDS IF THIS WILL OCCUR. THE GFS HAS BEEN
CONSISTENTLY SHOWING THE ABOVE...WHILE THE ECMWF IS NOT AS FAR
NORTH WITH THE PRECIPITATION SHIELD.
A BREAK IN THE PRECIPITATION THREAT IS POSSIBLE THURSDAY AND FRIDAY.
ANOTHER WET PERIOD SATURDAY BUT THE GFS AND ECMWF DIFFER ON PLACEMENT
OF THE PRECIPITATION AREA.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 636 PM CDT SAT APR 23 2016
MAIN HAZARDS TO AVIATION WILL BE GUSTY EAST WINDS AND A DEVELOPING
RAIN THAT WILL USHER IN WIDESPREAD IFR CONDITIONS FROM KDIK-
KBIS- KJMS ON SUNDAY. SURFACE LOW PRESSURE ACROSS WESTERN SOUTH
DAKOTA WILL MAINTAIN A STRONG EASTERLY WIND FLOW THROUGH THE
PERIOD. VFR EXPECTED THROUGH 08Z...THEN RAPIDLY DETERIORATING
CONDITIONS TO IFR IN RAIN AND BR AFTER 08Z. MVFR KISN-KMOT AFTER
09Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...KS
LONG TERM...KS
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
649 PM CDT SAT APR 23 2016
.UPDATE...
ISSUED AT 636 PM CDT SAT APR 23 2016
DEEP LOW PRESSURE OVER WESTERN SOUTH DAKOTA AND HIGH PRESSURE
ACROSS MANITOBA WERE ENHANCING THE LOW LEVEL WINDS ACROSS NORTH
DAKOTA. MOST AREAS HAD EAST WINDS OF 20 TO 35 MPH WITH A FEW
SITES ABOVE 40 MPH. EXPECT THE WINDS TO CONTINUE TONIGHT. WATER
VAPOR CHANNEL SHOWS THE 700 MB UPPER LOW IN THE VICINITY OF WEST
CENTRAL WYOMING. SCATTERED THUNDERSTORMS HAVE DEVELOPED INTO SOUTH
CENTRAL MONTANA SOUTHEAST THROUGH EASTERN WYOMING. EXPECT THIS
AREA TO ROTATE NORTHEAST INTO SOUTHWEST NORTH DAKOTA LATE TONIGHT.
OTHERWISE FOR THE NEXT 6 HOURS OR SO LOOKING AT SOME INCREASING
CLOUDS AND A STEADY EAST WIND OF 20 TO 40 MPH.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 313 PM CDT SAT APR 23 2016
MAIN HIGHLIGHTS THROUGH SUNDAY AFTERNOON: RAINFALL AMOUNTS
ESPECIALLY LOCATIONS WHERE TOTALS EXCEED ONE INCH...A FEW STRONG
THUNDERSTORMS SOUTHWEST TONIGHT WITH POSSIBLE SMALL HAIL AND
GUSTY WINDS...AND POTENTIAL WIND ADVISORY TURTLE MOUNTAINS AND
VICINITY SUNDAY.
THE LATEST WATER VAPOR IMAGERY SHOWS A CLOSED UPPER LOW CIRCULATING
OVER FAR SOUTHEAST IDAHO WITH A DEEPENING SURFACE LOW
DOWNSTREAM...POSITIONED OVER NORTHEAST WYOMING. A WARM FRONT
EXTENDED FROM THIS LOW AND WAS DRAPED ALONG THE SOUTHERN BORDER.
WITH THIS WARM FRONT REMAINING JUST SOUTH OF OUR BORDER
TONIGHT/SUNDAY...AND THE UPPER LOW CATCHING UP WITH THE SURFACE
LOW AND BECOMING A VERTICALLY STACKED SYSTEM OVER CENTRAL SOUTH
DAKOTA...A WELL DEFINED DEFORMATION ZONE SETS UP OVER ALL OF
CENTRAL AND SOUTHERN NORTH DAKOTA LATER TONIGHT THROUGH SUNDAY.
FORCING/VERTICAL MOTION PER Q-VECTOR DIVERGENCE FIELD AND STEEP
MID LEVEL LAPSE RATES APPEAR MAXIMIZED BETWEEN INTERSTATE 94 AND
JUST SOUTH OF HIGHWAY 2. THIS SHOULD SET THE STAGE FOR PERIODS OF
HEAVIER RAINFALL AND HIGHEST RAINFALL TOTALS THROUGH SUNDAY.
EXPECT BETWEEN 1 AND 1.4 INCHES OF TOTAL RAINFALL THROUGH SUNDAY
NIGHT BETWEEN INTERSTATE 94 AND HIGHWAY 2.
THUNDERSTORM POTENTIAL REMAINS ELEVATED THROUGH THE PERIOD WITH
DECREASING CIN AS MOISTURE INCREASES THROUGH THE COLUMN AND
STEEPENING MID LEVEL LAPSE RATES. BEST CHANCES WILL BE TONIGHT
THROUGH SUNDAY MORNING...WITH SOUNDINGS BECOMING SATURATED AND
SHOWING RELATIVELY SKINNY OR NO CAPE FIELD. ENVIRONMENT SHOULD
TRANSITION MORE TOWARDS A HEAVY RAIN VERSUS CONVECTIVE IN NATURE.
SPC HAS MAINTAINED THE MARGINAL RISK FOR SEVERE THUNDERSTORMS IN
THE FAR SOUTHWEST TONIGHT. THINKING IS CONVECTION WOULD BEGIN AFTER
03Z PER LATEST HRRR AND GRADUALLY INCREASE OVERNIGHT INTO MID
MORNING SUNDAY.
GUSTY NORTHEAST WINDS WILL CONTINUE TONIGHT THROUGH SUNDAY ACROSS
ALL OF WESTERN AND CENTRAL NORTH DAKOTA. THE STRONGEST WINDS ARE
FORECAST ALONG AND NORTH OF HIGHWAY 2...WITH THE TURTLE MOUNTAINS
PINPOINTED FOR THE HIGHEST SUSTAINED WINDS OF AROUND 30 MPH AND
GUSTS TO 45 MPH. FUTURE SHIFTS CAN RE-EVALUATE FOR A POSSIBLE WIND
ADVISORY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 313 PM CDT SAT APR 23 2016
THE VERTICALLY STACKED SYSTEM CONTINUES TO SLOWLY SHIFT EAST
SUNDAY NIGHT AND MONDAY WITH A GRADUAL DECREASE IN POPS. HOWEVER
THE ECMWF HAS BEEN CONSISTENTLY ADVERTISING HIGHER QPF AND COLDER
AIR ESPECIALLY ALONG AND SOUTH OF INTERSTATE 94 MONDAY. THUS HAVE
TRENDED POPS BETWEEN CHC/LIKELY WITH MOSTLY RAIN AND A LITTLE BIT
OF SNOW EXPECTED. SNOWFALL ACCUMULATIONS OF A COUPLE TENTHS POSSIBLE
SUNDAY NIGHT ACROSS THE WEST.
ANOTHER ROUND OF PRECIPITATION IS POSSIBLE TUESDAY NIGHT THROUGH
WEDNESDAY NIGHT MAINLY ACROSS SOUTHERN NORTH DAKOTA. THE GFS AND
ECMWF CONTINUE TO BE AT ODDS IF THIS WILL OCCUR. THE GFS HAS BEEN
CONSISTENTLY SHOWING THE ABOVE...WHILE THE ECMWF IS NOT AS FAR
NORTH WITH THE PRECIPITATION SHIELD.
A BREAK IN THE PRECIPITATION THREAT IS POSSIBLE THURSDAY AND FRIDAY.
ANOTHER WET PERIOD SATURDAY BUT THE GFS AND ECMWF DIFFER ON PLACEMENT
OF THE PRECIPITATION AREA.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 636 PM CDT SAT APR 23 2016
MAIN HAZARDS TO AVIATION WILL BE GUSTY EAST WINDS AND A DEVELOPING
RAIN THAT WILL USHER IN WIDESPREAD IFR CONDITIONS FROM KDIK-
KBIS- KJMS ON SUNDAY. SURFACE LOW PRESSURE ACROSS WESTERN SOUTH
DAKOTA WILL MAINTAIN A STRONG EASTERLY WIND FLOW THROUGH THE
PERIOD. VFR EXPECTED THROUGH 08Z...THEN RAPIDLY DETERIORATING
CONDITIONS TO IFR IN RAIN AND BR AFTER 08Z. MVFR KISN-KMOT AFTER
09Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...KS
LONG TERM...KS
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1204 PM CDT FRI APR 22 2016
.UPDATE...
ISSUED AT 1204 PM CDT FRI APR 22 2016
LATEST SURFACE ANALYSIS SHOWS INCREASING SOUTHEAST WINDS ACROSS
SOUTHWEST NORTH DAKOTA...ON TRACK WITH OUR GRIDDED WIND DATA. THE
LATEST HRRR EXPERIMENTAL CONTINUES TO PORTRAY DEWPOINTS IN THE 30S
AND THIS SEEMS REASONABLE GIVEN THE UPSTREAM OBSERVATIONS IN SOUTH
DAKOTA. NO CHANGES TO CURRENT FORECAST AT THIS TIME.
UPDATE ISSUED AT 1006 AM CDT FRI APR 22 2016
ONCE AGAIN...NO SIGNIFICANT CHANGES WITH THIS UPDATE. MORNING
SURFACE ANALYSES REVEAL SURFACE PRESSURE FALLS BEGINNING ACROSS
EASTERN MT AND THE WESTERN DAKOTAS AS A REFLECTION OF WARM AIR
ADVECTION ALOFT. THIS IS INDUCING INCREASING SOUTHEAST FLOW AND
GIVEN UPSTREAM OBSERVED DEWPOINTS IN THE 30S TO AROUND 40 F FROM
SD INTO NEB...SOME MODEST LOW-LEVEL MOISTURE ADVECTION WILL OCCUR
THIS AFTERNOON AND EVENING. GUIDANCE...INCLUDING THE EXPERIMENTAL/
ESRL-RUN HRRR THAT HAS VERIFIED WELL LATELY...SUGGESTS HUMIDITIES
IN FAR SOUTHWEST ND WILL NOT FALL BELOW 25 PERCENT ACROSS A LARGE
ENOUGH AREA TO WARRANT ISSUANCE OF A RED FLAG WARNING.
UPDATE ISSUED AT 640 AM CDT FRI APR 22 2016
NO SIGNIFICANT CHANGE WITH THIS FORECAST UPDATE OTHER THAN TO
BLEND TO OBSERVED TRENDS THROUGH 11 UTC. WILL CONTINUE TO MONITOR
CONDITIONS ACROSS SOUTHWEST NORTH DAKOTA THROUGH THE DAY SHOULD A
RED FLAG WARNING BECOME NECESSARY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CDT FRI APR 22 2016
POTENTIAL NEAR CRITICAL FIRE WEATHER CONDITIONS FAR SOUTHWEST
TODAY HIGHLIGHT THE SHORT TERM FORECAST. SEE THE FIRE WEATHER
DISCUSSION BELOW FOR DETAILS.
A STATIONARY FRONT ACROSS NORTH CENTRAL THROUGH SOUTHEAST MONTANA
THIS MORNING WILL PROPAGATE EAST TODAY AS A WARM FRONT AND
APPROACH FAR SOUTHWEST NORTH DAKOTA LATE THIS AFTERNOON. AS A
RESULT...A LARGE TEMPERATURE GRADIENT IS EXPECTED ACROSS THE AREA
TODAY WITH HIGHS IN THE 50S ACROSS THE TURTLE MOUNTAINS TO NEAR 80
ACROSS THE FAR SOUTHWEST. BREEZY SOUTHEAST WINDS OF 20 TO 30 MPH
ARE EXPECTED ACROSS THE WEST THIS AFTERNOON WITH A TIGHTENING
PRESSURE GRADIENT AND ISALLOBARIC FORCING FROM PRESSURE FALLS
AHEAD OF THE WARM FRONT. GIVEN GOOD AGREEMENT...A BLEND OF THE 00
UTC GLOBAL AND HIGH RESOLUTION SUITES WERE USED...WITH PREFERENCE
GIVEN TO THE WARMER EDGE OF GUIDANCE FOR TEMPERATURES ACROSS THE
WEST PER VERIFICATION TRENDS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 302 AM CDT FRI APR 22 2016
WIDESPREAD PRECIPITATION LATE SATURDAY NIGHT THROUGH MONDAY
MORNING HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC DETERMINISTIC AND ENSEMBLE GLOBAL SUITES ARE IN GOOD
AGREEMENT ON THE UPPER LOW COMING ON SHORE TO CALIFORNIA AND
OREGON TODAY PROPAGATING INTO THE NORTHERN PLAINS SATURDAY NIGHT
THROUGH MONDAY MORNING. THE TREND OVER THE LAST 24 HOURS HAS BEEN
FOR A SLIGHT NORTHWARD SHIFT IN THE LOW TRACK...YIELDING MORE
WIDESPREAD AND HIGHER PRECIPITATION CHANCES ACROSS MUCH OF WESTERN
AND CENTRAL NORTH DAKOTA.
REGARDING DETAILS...SURFACE CYCLOGENESIS IS FORECAST ACROSS
WESTERN SOUTH DAKOTA SATURDAY NIGHT INTO SUNDAY MORNING WITH
RESULTING INCREASING MOISTURE TRANSPORT INTO THE REGION. WITH
STRONG DIFFLUENCE ALOFT AND STEEP MID LEVEL LAPSE
RATES...THUNDERSTORMS ARE POSSIBLE SATURDAY NIGHT INTO SUNDAY
MORNING MORNING. CERTAINLY COULD NOT RULE OUT A FEW STRONG
ELEVATED STORMS ACROSS SOUTHERN NORTH DAKOTA WITH MUCAPE OF
500-1000 J/KG AT 750 MB AND THE PRESENCE OF STRONG DEEP LAYER
SHEAR. PRECIPITATION ACROSS NORTH DAKOTA IS FORECAST TO TRANSITION
TO STRATIFORM THROUGH THE DAY ON SUNDAY AS THE SYSTEM BECOMES
NEARLY VERTICALLY STACKED ACROSS SOUTH CENTRAL SOUTH DAKOTA. AS
SUB- FREEZING LOW LEVEL AIR ADVECTS INTO THE SYSTEM SUNDAY NIGHT
INTO MONDAY MORNING...RAIN MAY TRANSITION TO SNOW WITH PERHAPS
LIGHT ACCUMULATIONS ON GRASSY SURFACES. WIDESPREAD RAINFALL TOTALS
OVER AN INCH ARE STILL FORECAST SOUTH OF US HIGHWAY 2.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1204 PM CDT FRI APR 22 2016
VFR CONDITIONS ARE FORECAST ACROSS WESTERN AND CENTRAL ND THROUGH
THE 18 UTC TAF CYCLE. HOWEVER...THERE IS A LOW PROBABILITY OF MVFR
OR EVEN IFR CEILINGS /STRATUS/ DEVELOPING OVER THE SOUTHERN JAMES
RIVER VALLEY BETWEEN 09 AND 15 UTC. OTHERWISE...BREEZY SOUTHEAST
WINDS WITH GUSTS TO 30 KT ARE EXPECTED ACROSS WESTERN ND AT KISN AND
KDIK THIS AFTERNOON. LOW-LEVEL WIND SHEAR IS POSSIBLE AT KDIK...KBIS
AND KJMS TONIGHT AND EARLY SATURDAY MORNING.
&&
.FIRE WEATHER...
ISSUED AT 1006 AM CDT FRI APR 22 2016
NEAR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED ACROSS FAR
SOUTHWEST NORTH DAKOTA TODAY IN GOLDEN VALLEY...SLOPE...BILLINGS
AND BOWMAN COUNTIES. HIGH TEMPERATURES TODAY WILL BE IN THE UPPER
70S WITH SOUTHEAST WINDS OF 20 TO 25 MPH...GUSTING AT 30 TO 35
MPH. OF GREATEST UNCERTAINTY ARE FORECAST RELATIVE HUMIDITY
VALUES. AFTERNOON RELATIVE HUMIDITY MAY FALL INTO THE 20 TO 25
PERCENT RANGE THIS AFTERNOON...WITH EVEN LOWER VALUES POSSIBLE
ACROSS THE BORDER IN MONTANA. HOWEVER...THE LATEST INDICATIONS ARE
THAT HUMIDITY VALUES WILL NOT FALL LOW ENOUGH OVER A LARGE ENOUGH
AREA OF ANY GIVEN COUNTY TO WARRANT ISSUANCE OF A RED FLAG WARNING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...AYD
LONG TERM...AYD
AVIATION...CJS
FIRE WEATHER...AYD/CJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1006 AM CDT FRI APR 22 2016
.UPDATE...
ISSUED AT 1006 AM CDT FRI APR 22 2016
ONCE AGAIN...NO SIGNIFICANT CHANGES WITH THIS UPDATE. MORNING
SURFACE ANALYSES REVEAL SURFACE PRESSURE FALLS BEGINNING ACROSS
EASTERN MT AND THE WESTERN DAKOTAS AS A REFLECTION OF WARM AIR
ADVECTION ALOFT. THIS IS INDUCING INCREASING SOUTHEAST FLOW AND
GIVEN UPSTREAM OBSERVED DEWPOINTS IN THE 30S TO AROUND 40 F FROM
SD INTO NEB...SOME MODEST LOW-LEVEL MOISTURE ADVECTION WILL OCCUR
THIS AFTERNOON AND EVENING. GUIDANCE...INCLUDING THE EXPERIMENTAL/
ESRL-RUN HRRR THAT HAS VERIFIED WELL LATELY...SUGGESTS HUMIDITIES
IN FAR SOUTHWEST ND WILL NOT FALL BELOW 25 PERCENT ACROSS A LARGE
ENOUGH AREA TO WARRANT ISSUANCE OF A RED FLAG WARNING.
UPDATE ISSUED AT 640 AM CDT FRI APR 22 2016
NO SIGNIFICANT CHANGE WITH THIS FORECAST UPDATE OTHER THAN TO
BLEND TO OBSERVED TRENDS THROUGH 11 UTC. WILL CONTINUE TO MONITOR
CONDITIONS ACROSS SOUTHWEST NORTH DAKOTA THROUGH THE DAY SHOULD A
RED FLAG WARNING BECOME NECESSARY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 320 AM CDT FRI APR 22 2016
POTENTIAL NEAR CRITICAL FIRE WEATHER CONDITIONS FAR SOUTHWEST
TODAY HIGHLIGHT THE SHORT TERM FORECAST. SEE THE FIRE WEATHER
DISCUSSION BELOW FOR DETAILS.
A STATIONARY FRONT ACROSS NORTH CENTRAL THROUGH SOUTHEAST MONTANA
THIS MORNING WILL PROPAGATE EAST TODAY AS A WARM FRONT AND
APPROACH FAR SOUTHWEST NORTH DAKOTA LATE THIS AFTERNOON. AS A
RESULT...A LARGE TEMPERATURE GRADIENT IS EXPECTED ACROSS THE AREA
TODAY WITH HIGHS IN THE 50S ACROSS THE TURTLE MOUNTAINS TO NEAR 80
ACROSS THE FAR SOUTHWEST. BREEZY SOUTHEAST WINDS OF 20 TO 30 MPH
ARE EXPECTED ACROSS THE WEST THIS AFTERNOON WITH A TIGHTENING
PRESSURE GRADIENT AND ISALLOBARIC FORCING FROM PRESSURE FALLS
AHEAD OF THE WARM FRONT. GIVEN GOOD AGREEMENT...A BLEND OF THE 00
UTC GLOBAL AND HIGH RESOLUTION SUITES WERE USED...WITH PREFERENCE
GIVEN TO THE WARMER EDGE OF GUIDANCE FOR TEMPERATURES ACROSS THE
WEST PER VERIFICATION TRENDS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 302 AM CDT FRI APR 22 2016
WIDESPREAD PRECIPITATION LATE SATURDAY NIGHT THROUGH MONDAY
MORNING HIGHLIGHTS THE EXTENDED FORECAST.
THE 00 UTC DETERMINISTIC AND ENSEMBLE GLOBAL SUITES ARE IN GOOD
AGREEMENT ON THE UPPER LOW COMING ON SHORE TO CALIFORNIA AND
OREGON TODAY PROPAGATING INTO THE NORTHERN PLAINS SATURDAY NIGHT
THROUGH MONDAY MORNING. THE TREND OVER THE LAST 24 HOURS HAS BEEN
FOR A SLIGHT NORTHWARD SHIFT IN THE LOW TRACK...YIELDING MORE
WIDESPREAD AND HIGHER PRECIPITATION CHANCES ACROSS MUCH OF WESTERN
AND CENTRAL NORTH DAKOTA.
REGARDING DETAILS...SURFACE CYCLOGENESIS IS FORECAST ACROSS
WESTERN SOUTH DAKOTA SATURDAY NIGHT INTO SUNDAY MORNING WITH
RESULTING INCREASING MOISTURE TRANSPORT INTO THE REGION. WITH
STRONG DIFFLUENCE ALOFT AND STEEP MID LEVEL LAPSE
RATES...THUNDERSTORMS ARE POSSIBLE SATURDAY NIGHT INTO SUNDAY
MORNING MORNING. CERTAINLY COULD NOT RULE OUT A FEW STRONG
ELEVATED STORMS ACROSS SOUTHERN NORTH DAKOTA WITH MUCAPE OF
500-1000 J/KG AT 750 MB AND THE PRESENCE OF STRONG DEEP LAYER
SHEAR. PRECIPITATION ACROSS NORTH DAKOTA IS FORECAST TO TRANSITION
TO STRATIFORM THROUGH THE DAY ON SUNDAY AS THE SYSTEM BECOMES
NEARLY VERTICALLY STACKED ACROSS SOUTH CENTRAL SOUTH DAKOTA. AS
SUB- FREEZING LOW LEVEL AIR ADVECTS INTO THE SYSTEM SUNDAY NIGHT
INTO MONDAY MORNING...RAIN MAY TRANSITION TO SNOW WITH PERHAPS
LIGHT ACCUMULATIONS ON GRASSY SURFACES. WIDESPREAD RAINFALL TOTALS
OVER AN INCH ARE STILL FORECAST SOUTH OF US HIGHWAY 2.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 640 AM CDT FRI APR 22 2016
VFR CONDITIONS ARE EXPECTED ACROSS WESTERN AND CENTRAL NORTH
DAKOTA FOR THE 06 UTC TAF CYCLE. BREEZY SOUTHEAST WINDS WITH
GUSTS OF 25-30 KTS ARE FORECAST AT KISN AND KDIK THIS AFTERNOON.
LOW LEVEL WIND SHEAR IS POSSIBLE AT KDIK/KBIS TONIGHT.
&&
.FIRE WEATHER...
ISSUED AT 1006 AM CDT FRI APR 22 2016
NEAR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED ACROSS FAR
SOUTHWEST NORTH DAKOTA TODAY IN GOLDEN VALLEY...SLOPE...BILLINGS
AND BOWMAN COUNTIES. HIGH TEMPERATURES TODAY WILL BE IN THE UPPER
70S WITH SOUTHEAST WINDS OF 20 TO 25 MPH...GUSTING AT 30 TO 35
MPH. OF GREATEST UNCERTAINTY ARE FORECAST RELATIVE HUMIDITY
VALUES. AFTERNOON RELATIVE HUMIDITY MAY FALL INTO THE 20 TO 25
PERCENT RANGE THIS AFTERNOON...WITH EVEN LOWER VALUES POSSIBLE
ACROSS THE BORDER IN MONTANA. HOWEVER...THE LATEST INDICATIONS ARE
THAT HUMIDITY VALUES WILL NOT FALL LOW ENOUGH OVER A LARGE ENOUGH
AREA OF ANY GIVEN COUNTY TO WARRANT ISSUANCE OF A RED FLAG WARNING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CJS
SHORT TERM...AYD
LONG TERM...AYD
AVIATION...AYD
FIRE WEATHER...AYD/CJS
AREA FORECAST DISCUSSION
NWS PORTLAND OR
325 PM PDT FRI APR 22 2016
CORRECTED MARINE AND AVIATION SECTIONS
.SYNOPSIS...A COOL LOW PRESSURE SYSTEM WILL BE OVER OREGON FOR
MORE SHOWERS AND POSSIBLY AN AFTERNOON THUNDERSTORM...THEN MOVE EAST
OF SOUTHWEST WASHINGTON AND NORTHWEST OREGON LATER TONIGHT AND EARLY
SATURDAY FOR DECREASING SHOWERS. THE NEXT SYSTEM WILL SPREAD MORE
SHOWERS INTO THE FORECAST AREA LATER SATURDAY AND SATURDAY NIGHT. THE
ASSOCIATED EVEN COLDER LOW WILL NOT MOVE OUT OF THE FORECAST AREA
UNTIL LATER MONDAY AND MONDAY NIGHT. THIS LOW WILL DROP SNOW LEVELS
BELOW THE CASCADE PASSES SATURDAY NIGHT THROUGH MONDAY... AND SEVERAL
INCHES OF SNOW ARE POSSIBLE. THE NEXT SYSTEM IS EXPECTED TUESDAY
NIGHT AND WEDNESDAY AS UNSETTLED WEATHER CONTINUES.
&&
.SHORT TERM...SHOWER ACTIVITY IS SLOW TO INCREASE THIS AFTERNOON.
CURRENT INSTABILITY ANALYSIS AND HRRR MODEL TRENDS SHOW STRONGER
SHOWER ACTIVITY IN THE NEXT FEW HOURS. THE HRRR MODEL RECENTLY
DEPICTING STRONGER SHOWERS OVER THE COAST RANGE AND OREGON CASCADES
WITH A FEW CELLS OVER THE CENTRAL AND SOUTH VALLEY FROM ABOUT 3 PM TO
6 PM. THERE WAS A REPORT OF A FUNNEL CLOUD NEAR MONMOUTH LATE THIS
MORNING. NAM BUFR SOUNDING SHOW WEAK LOW LEVEL DIRECTIONAL WIND SHEAR
FOR THAT TIME SO ITS POSSIBLE THAT THE INITIAL RELEASE OF INSTABILITY
ALLOWED A SHOWER TO SPIN UP THIS FUNNEL. MODEL SOUNDINGS SHOW LESS
FAVORABLE CONDITIONS FOR FUNNEL CLOUDS THIS AFTERNOON.
MODELS SHOW THE AIR MASS STABILIZING A LOT QUICKER THAN THE THU NIGHT
SYSTEM SO EXPECT THREAT OF THUNDERSTORMS TO QUICKLY DIMINISH BY 7 OR
8 PM. PRECIPITATION AMOUNTS DO NOT LOOK AS HEAVY THIS AFTERNOON AND
EVENING IN A LARGE SCALE SENSE...THOUGH INDIVIDUAL CELLS COULD STILL
PRODUCE HEAVY RAIN. THE UPPER LOW MOVES EAST OF THE FORECAST AREA
LATER TONIGHT AND SATURDAY MORNING WITH SHOWER ACTIVITY MAINLY OVER
THE MOUNTAINS THEN INCREASE AGAIN OVER THE LOWLANDS IN THE AFTERNOON.
THERE IS INDICATION OF RENEWED INSTABILITY SAT AFTERNOON BUT
SHOWERS SHOULD REMAIN CAPPED BELOW -10C LEVEL. THE NEXT SYSTEM
APPROACHES LATER SATURDAY AND PUSHES A FRONT INTO THE AREA SATURDAY
NIGHT FOR MORE SHOWERS. THE ASSOCIATED COOL UPPER TROUGH SAGS ACROSS
THE AREA SAT NIGHT AND SUN WITH LOWERING SNOW LEVELS. THE CASCADE
PASSES WILL PROBABLY SEE SEVERAL INCHES OF NEW SNOW BY SUN AFTERNOON.
THE COOL UPPER TROUGH WILL BRING ALSO INCREASE INSTABILITY SO WILL
INCLUDE A SLIGHT CHANCE OF THUNDERSTORMS ON SUN.
TOTAL RAINFALL ACCUMULATIONS THROUGH SUNDAY COULD REACH 1 TO 1.5
ALONG THE COAST AND IN THE MOUNTAINS...AND FROM 0.50 TO 1 INCHES IN
THE VALLEYS. THUS THIS LOOKS TO BE A REASONABLY WET PERIOD AFTER OUR
RECENT COUPLE OF UNSEASONABLY WARM SPELLS. /MH
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY. SHOWERS START TAPERING OFF
MONDAY NIGHT AS SHORTWAVE RIDGING BUILDS IN TO THE PACIFIC
NORTHWEST. TUESDAY FOR THE MOST PART LOOKS DRY. MODELS HAVE BEEN
VERY INCONSISTENT WITH THE FORECAST FOR MID-TO-LATE WEEK NEXT
WEEK...BUT IT IS STARTING TOO LOOK LIKE THE NEXT SYSTEM WILL
PROBABLY DROP TO OUR SOUTH. THIS MAY CLIP SOUTHERN PARTS OF OUR
AREA...BUT AREAS SALEM NORTHWARD WILL PROBABLY STAY DRY. HAVE LEFT A
SLIGHT CHANCE OF SHOWERS ACROSS OUR AREA TO ACCOUNT FOR THE
INCONSISTENCY WITH THE TRACK OF THIS SYSTEM BETWEEN MODEL RUNS. WILL
PROBABLY SEE FORECAST TREND DRIER IF MODELS CONTINUE TO SHOW THIS
SYSTEM DROPPING SOUTH OF US. ON THURSDAY WE SEE A SHORTWAVE TROUGH
DROP DOWN OUT OF CANADA ALONG THE EAST SIDE OF THE CASCADES BRINGING
SHOWERS TO THE CASCADE CREST...BUT FURTHER WEST WILL PROBABLY BE DRY
AS RIDGING STARTS TO BUILD BACK OVER THE EASTERN PACIFIC ALONG THE
WEST COAST. MODELS DIFFER ABOUT WHETHER THIS RIDGE PERSISTS INTO THE
WEEKEND...OR IS ONLY A TEMPORARY REPRIEVE BEFORE MORE RAIN MOVES IN
OVER THE WEEKEND...THEREFORE CONFIDENCE IS LOW AT THIS TIME IN THE
FORECAST FOR FRIDAY AND BEYOND. -MCCOY
&&
.AVIATION...MOIST AND UNSTABLE AIR MASS CONTINUES TO PRODUCE
SCATTERED SHOWERS ACROSS THE FORECAST AREA...THOUGH CONDITIONS IN
GENERAL REMAIN VFR. HEAVIER SHOWERS MAY BRIEFLY LOWER CIGS/VSBYS
INTO THE MVFR CATEGORY BEFORE MOVING ALONG SLOWLY TO THE NORTH.
ISOLD TSRA REMAIN POSSIBLE DUE TO THE INSTABILITY...THOUGH TODAYS
CONVECTION SHOULD BE LESS ORGANIZED THAN IT HAS BEEN THE PAST
COUPLE DAYS. SHOWERS SHOULD TAPER OFF QUICKLY AFTER SUNSET DUE TO
LOSS OF DAYTIME HEATING. SOME RELATIVE CLEARING IS POSSIBLE THIS
EVENING...WHICH COULD LEAD TO SOME VERY THIN PATCHES OF GROUND FOG
AT THE MORE FOG-PRONE TERMINALS LIKE KEUG/KHIO THIS EVENING.
HIGHER CLOUD COVER IS EXPECTED TO INCREASE SAT MORNING AHEAD OF AN
APPROACHING WEAK COLD FRONT...WHICH SHOULD MITIGATE FOG FORMATION.
WILL HINT AT SOME MIFG IN KHIO/KEUG TAFS...BUT WILL KEEP
PREVAILING WX VFR UNTIL SHOWERS ARRIVE AHEAD OF THE COLD FRONT
AROUND 18Z SAT. THERE IS ALSO ABOUT A 40 PERCENT CHANCE OF A LOW
CLOUD DECK DEVELOPING WITH BASES AROUND 2000-3000 FT LATER
TONIGHT OR SAT AM...WHICH WOULD ALSO INHIBIT FOG FORMATION IF IT
DEVELOPS.
KPDX AND APPROACHES...EXPECT VFR TO PREVAIL MOST OF THE TIME
THROUGH TONIGHT WITH GENERAL LIGHT-MDT S-SW FLOW. ANOTHER ROUND
OF SHRA/ISOLD TSRA IS DEVELOPING THIS AFTERNOON DUE TO THE MOIST
AND UNSTABLE AIR MASS. CONVECTION THIS AFTERNOON SHOULD BE LESS
ORGANIZED THAN THE LAST COUPLE DAYS...BUT COULD STILL PRODUCE
BRIEF MVFR AND LOCALIZED GUSTY OUTFLOW UP TO 25 KT. SHRA SHOULD
DISSIPATE QUICKLY AFTER 02Z WITH LOSS OF DAYTIME HEATING. AREAS OF
MVFR WILL LIKELY DEVELOP AS LOW CLOUDS FORM LATER TONIGHT...THOUGH
ONLY ABOUT A 40 PERCENT CHANCE OF MVFR IMPACTING THE PDX TERMINAL
ITSELF. WEAGLE
&&
.MARINE...S-SW WINDS ARE EASING THIS AFTERNOON AFTER AN EARLIER
SURGE BROUGHT SOME GUSTS TO 25 KT TO MOST OF THE COASTAL WATERS.
WILL HOLD ON TO THE SCA FOR WIND IN THE NORTHERN WATERS UNTIL
4 PM FOR THE NORTHERN WATERS...AS THERE ARE STILL A FEW GUSTS
NEAR 20 KT BEING REPORTED ALONG THE COAST. LOW CENTER PRESENTLY
NEAR 43N/128W WILL SLOWLY MEANDER ONSHORE INTO SOUTHERN OR
TONIGHT/EARLY SAT MORNING...AND THERE MAY BE A BRIEF SURGE OF S-SW
WINDS GUSTING TO 20 KT EARLY SAT DUE TO THE REMNANTS OF THE LOWS
OCCLUDED FRONT. THAT SAID...IT APPEARS WINDS WILL REMAIN BELOW SCA
CRITERIA SAT MORNING. A BATCH OF WESTERLY SWELL ASSOCIATED WITH
THE LOW IS AIMING FOR THE CENTRAL/S OREGON COAST AND SHOULD PUSH
SEAS BACK UP TO 10+ FT TONIGHT. WILL ISSUE AN SCA FOR SEAS FOR OUR
SOUTHERN WATERS LATER TONIGHT/SAT.
HIGH PRESSURE BUILDING IN BEHIND THE LOW WILL CAUSE WINDS TO VEER
NW AND INCREASE SAT NIGHT/SUN...WITH GUSTS 20-25 KT PERSISTING
THROUGH EARLY MON. HIGH PRES RIDGE AXIS WILL SLIDE ACROSS THE
WATERS LATER MON/TUE FOR LIGHTER WINDS AND SEAS. WEAGLE
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 4 PM PDT THIS AFTERNOON
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD
OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 11 PM THIS EVENING
TO 5 PM PDT SATURDAY FOR COASTAL WATERS FROM CASCADE HEAD
OR TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 2 AM TO
9 AM PDT SATURDAY.
&&
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 4 PM PDT THIS AFTERNOON
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD
OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM PDT THIS MORNING FOR
COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60
NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 2 AM TO
9 AM PDT SATURDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS PORTLAND OR
225 PM PDT FRI APR 22 2016
.SYNOPSIS...A COOL LOW PRESSURE SYSTEM WILL BE OVER OREGON FOR
MORE SHOWERS AND POSSIBLY AN AFTERNOON THUNDERSTORM...THEN MOVE EAST
OF SOUTHWEST WASHINGTON AND NORTHWEST OREGON LATER TONIGHT AND EARLY
SATURDAY FOR DECREASING SHOWERS. THE NEXT SYSTEM WILL SPREAD MORE
SHOWERS INTO THE FORECAST AREA LATER SATURDAY AND SATURDAY NIGHT. THE
ASSOCIATED EVEN COLDER LOW WILL NOT MOVE OUT OF THE FORECAST AREA
UNTIL LATER MONDAY AND MONDAY NIGHT. THIS LOW WILL DROP SNOW LEVELS
BELOW THE CASCADE PASSES SATURDAY NIGHT THROUGH MONDAY... AND SEVERAL
INCHES OF SNOW ARE POSSIBLE. THE NEXT SYSTEM IS EXPECTED TUESDAY
NIGHT AND WEDNESDAY AS UNSETTLED WEATHER CONTINUES.
&&
.SHORT TERM...SHOWER ACTIVITY IS SLOW TO INCREASE THIS AFTERNOON.
CURRENT INSTABILITY ANALYSIS AND HRRR MODEL TRENDS SHOW STRONGER
SHOWER ACTIVITY IN THE NEXT FEW HOURS. THE HRRR MODEL RECENTLY
DEPICTING STRONGER SHOWERS OVER THE COAST RANGE AND OREGON CASCADES
WITH A FEW CELLS OVER THE CENTRAL AND SOUTH VALLEY FROM ABOUT 3 PM TO
6 PM. THERE WAS A REPORT OF A FUNNEL CLOUD NEAR MONMOUTH LATE THIS
MORNING. NAM BUFR SOUNDING SHOW WEAK LOW LEVEL DIRECTIONAL WIND SHEAR
FOR THAT TIME SO ITS POSSIBLE THAT THE INITIAL RELEASE OF INSTABILITY
ALLOWED A SHOWER TO SPIN UP THIS FUNNEL. MODEL SOUNDINGS SHOW LESS
FAVORABLE CONDITIONS FOR FUNNEL CLOUDS THIS AFTERNOON.
MODELS SHOW THE AIR MASS STABILIZING A LOT QUICKER THAN THE THU NIGHT
SYSTEM SO EXPECT THREAT OF THUNDERSTORMS TO QUICKLY DIMINISH BY 7 OR
8 PM. PRECIPITATION AMOUNTS DO NOT LOOK AS HEAVY THIS AFTERNOON AND
EVENING IN A LARGE SCALE SENSE...THOUGH INDIVIDUAL CELLS COULD STILL
PRODUCE HEAVY RAIN. THE UPPER LOW MOVES EAST OF THE FORECAST AREA
LATER TONIGHT AND SATURDAY MORNING WITH SHOWER ACTIVITY MAINLY OVER
THE MOUNTAINS THEN INCREASE AGAIN OVER THE LOWLANDS IN THE AFTERNOON.
THERE IS INDICATION OF RENEWED INSTABILITY SAT AFTERNOON BUT
SHOWERS SHOULD REMAIN CAPPED BELOW -10C LEVEL. THE NEXT SYSTEM
APPROACHES LATER SATURDAY AND PUSHES A FRONT INTO THE AREA SATURDAY
NIGHT FOR MORE SHOWERS. THE ASSOCIATED COOL UPPER TROUGH SAGS ACROSS
THE AREA SAT NIGHT AND SUN WITH LOWERING SNOW LEVELS. THE CASCADE
PASSES WILL PROBABLY SEE SEVERAL INCHES OF NEW SNOW BY SUN AFTERNOON.
THE COOL UPPER TROUGH WILL BRING ALSO INCREASE INSTABILITY SO WILL
INCLUDE A SLIGHT CHANCE OF THUNDERSTORMS ON SUN.
TOTAL RAINFALL ACCUMULATIONS THROUGH SUNDAY COULD REACH 1 TO 1.5
ALONG THE COAST AND IN THE MOUNTAINS...AND FROM 0.50 TO 1 INCHES IN
THE VALLEYS. THUS THIS LOOKS TO BE A REASONABLY WET PERIOD AFTER OUR
RECENT COUPLE OF UNSEASONABLY WARM SPELLS. /MH
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY. SHOWERS START TAPERING OFF
MONDAY NIGHT AS SHORTWAVE RIDGING BUILDS IN TO THE PACIFIC
NORTHWEST. TUESDAY FOR THE MOST PART LOOKS DRY. MODELS HAVE BEEN
VERY INCONSISTENT WITH THE FORECAST FOR MID-TO-LATE WEEK NEXT
WEEK...BUT IT IS STARTING TOO LOOK LIKE THE NEXT SYSTEM WILL
PROBABLY DROP TO OUR SOUTH. THIS MAY CLIP SOUTHERN PARTS OF OUR
AREA...BUT AREAS SALEM NORTHWARD WILL PROBABLY STAY DRY. HAVE LEFT A
SLIGHT CHANCE OF SHOWERS ACROSS OUR AREA TO ACCOUNT FOR THE
INCONSISTENCY WITH THE TRACK OF THIS SYSTEM BETWEEN MODEL RUNS. WILL
PROBABLY SEE FORECAST TREND DRIER IF MODELS CONTINUE TO SHOW THIS
SYSTEM DROPPING SOUTH OF US. ON THURSDAY WE SEE A SHORTWAVE TROUGH
DROP DOWN OUT OF CANADA ALONG THE EAST SIDE OF THE CASCADES BRINGING
SHOWERS TO THE CASCADE CREST...BUT FURTHER WEST WILL PROBABLY BE DRY
AS RIDGING STARTS TO BUILD BACK OVER THE EASTERN PACIFIC ALONG THE
WEST COAST. MODELS DIFFER ABOUT WHETHER THIS RIDGE PERSISTS INTO THE
WEEKEND...OR IS ONLY A TEMPORARY REPRIEVE BEFORE MORE RAIN MOVES IN
OVER THE WEEKEND...THEREFORE CONFIDENCE IS LOW AT THIS TIME IN THE
FORECAST FOR FRIDAY AND BEYOND. -MCCOY
&&
.AVIATION...PLENTY OF SHOWERS EXPECTED TODAY ACROSS THE REGION...
THOUGH THE PREVAILING FLIGHT CATEGORY ON AVERAGE WILL BE VFR.
OCCASIONAL MVFR CIGS/VSBYS WILL OCCUR WITH HEAVIER SHOWERS. DRY
SLOT BEHIND INITIAL BATCH OF SHOWERS...PRESENTLY S OF KSLE...WILL
LIKELY BRING A BREAK IN THE ACTIVITY FROM S TO N DURING THE MIDDAY
HOURS. HOWEVER IT DOES APPEAR THERE WILL BE ENOUGH INSTABILITY FOR
ADDITIONAL SHOWERS AND ISOLD TSRA TO DEVELOP LATER THIS AFTERNOON
AND EVENING...THOUGH TODAYS CONVECTION SHOULD BE LESS ORGANIZED
THAN IT HAS BEEN THE PAST COUPLE DAYS.
KPDX AND APPROACHES...FIRST BATCH OF HEAVY SHOWERS FROM EARLIER
THIS MORNING HAS GENERALLY MOVED NW OF THE PDX METRO AREA...SO
EXPECT VFR TO PREVAIL MUCH OF THE DAY. COULD BE AREAS OF -RA AND
MVFR PERSISTING UNTIL ABOUT 18Z. ANOTHER ROUND OF SHRA/ISOLD TSRA
POSSIBLE AFTER 20Z...BUT SHOULD BE LESS ORGANIZED THAN PREVIOUS
CONVECTION THE LAST COUPLE DAYS. WEAGLE
&&
.MARINE...COLD FRONT CONTINUES TO LIFT N THROUGH THE NORTHERN
OREGON COASTAL WATERS THIS MORNING...WITH A BRIEF BURST OF S WINDS
BEHIND IT. BUOY 46050 HAD A BRIEF GUST TO 33 KT AT 13Z...LIKELY
AIDED BY A SQUALL LINE THAT DEVELOPED WITH THE FRONT. THIS APPEARS
TO HAVE STIRRED UP SEAS LOCALLY...WITH BUOY 46050 REPORTING 9 FT
AT 8 SEC AT THE MOMENT. DECIDED NOT TO ISSUE AN SCA FOR SEAS DUE
TO THE APPARENTLY LOCALIZED NATURE OF THESE SEAS...AND EXPECT THE
SEAS TO SETTLE DOWN TO 5-7 FT LATER TODAY. HOWEVER A BATCH OF
WESTERLY SWELL IS AIMING FOR THE CENTRAL/S OREGON COAST AND SHOULD
PUSH SEAS BACK UP TO 10+ FT TONIGHT. WILL LIKELY NEED TO ISSUE AN
SCA FOR SEAS FOR AT LEAST OUR SOUTHERN WATERS LATER TONIGHT/SAT.
OTHERWISE BROAD LOW PRESSURE WILL PREVAIL OVER THE WATERS THROUGH
THE WEEKEND...CONTINUING THE UNSETTLED WEATHER BUT KEEPING PRES
GRADIENTS RATHER LIGHT FOR LIGHT TO MODERATE S-SW WINDS. NEXT COLD
FRONT CROSSING 150W MAY BRING A BRIEF SURGE IN NW WINDS WITH GUSTS
20-25 KT AS COOL AIR PUSHES IN BEHIND IT SAT NIGHT/SUN AM. HIGH
PRES EXPECTED TO BUILD IN MON/TUE FOR LIGHTER WINDS/SEAS EARLY
NEXT WEEK. WEAGLE
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 4 PM PDT THIS AFTERNOON
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD
OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM PDT THIS MORNING FOR
COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60
NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 2 AM TO
9 AM PDT SATURDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS PENDLETON OR
1030 PM PDT THU APR 21 2016
.UPDATE...A TROUGH CONTINUES TO APPROACH THE COAST THIS EVENING AS
THE RIDGE THAT HAS BEEN OVER THE AREA MOVES EAST. A WAVE EMBEDDED IN
THE SOUTHERLY FLOW OVER WASHINGTON AND OREGON HAS BEEN GENERATING
SHOWERS AND A THUNDERSTORM OR TWO WEST OF THE CASCADES. MODELS SHOW
THE DISTURBANCE MOVING INTO OUR AREA OVERNIGHT. THE NAM AND THE
SHORT TERM HRRR AND RUC13 MODELS ALL SHOW SHOWERS DEVELOPING LATER
TONIGHT OVER THE EASTERN MOUNTAINS AND PROPAGATING NORTH THROUGH THE
COLUMBIA BASIN BEFORE EXITING AROUND SUNRISE. RADAR IS ALREADY
SHOWING SOME ECHOES IN NORTHERN MALHEUR AND BAKER COUNTIES AND SEE
CELLS DEVELOPING IN NORTHERN NEVADA SO HAVE ADDED ISOLATED RAIN
SHOWERS FROM JOHN DAY EASTWARD IN THE MOUNTAINS AND FROM HANFORD
EASTWARD IN THE COLUMBIA BASIN. HAVE KEPT THE ISOLATED SHOWERS ALONG
THE CASCADES AND INTO CENTRAL OREGON NORTH TO YAKIMA AND ELLENSBURG.
HAVE ALSO RAISED CLOUD COVER TO MOSTLY CLOUDY FOR THE REST OF THE
NIGHT. MADE A FEW SMALL ADJUSTMENTS TO THE WIND AS WELL. REST OF THE
FORECAST LOOKED GOOD. FORECAST UPDATES ALREADY OUT. PERRY
.AVIATION...06Z TAFS. CEILINGS BKN 060-100 TONIGHT INTO FRIDAY. A
FEW SHOWERS POSSIBLE EARLY TONIGHT FROM BDN/RDM TO DLS. OTHERWISE
BEST CHANCE OF SHOWERS AND ISOLATED THUNDERSTORMS WILL BE FRIDAY.
WINDS 5-10KT TONIGHT INCREASING TO 10-20KT LATER FRIDAY.
&&
.SHORT TERM...TONIGHT THROUGH SUNDAY...THE HIGH PRESSURE RIDGE AXIS
IS SHIFTING EASTWARD AS A TROUGH OF LOW PRESSURE IN THE GULF OF
ALASKA SLIDES TOWARD THE PACIFIC NORTHWEST. THE TROUGH WILL FORM A
CLOSED LOW OFF THE SOUTHWEST COAST OF OREGON BY FRIDAY AFTERNOON.
THE ATMOSPHERE OVER EASTERN OREGON AND WASHINGTON WILL BEGIN TO
DESTABILIZE FRIDAY AS THE LOW APPROACHES LEADING TO AN INCREASE IN
SHOWERS AND THUNDERSTORMS ACROSS THE FORECAST AREA. THE LOW WILL
THEN MOVE OVER THE REGION FRIDAY NIGHT AND EXIT EARLY SATURDAY WITH
SHOWERS DECREASING OVERNIGHT. MODELS ARE HINTING THAT SOME MOISTURE
WRAPPING BACK AROUND THE LOW COULD IMPACT FAR NORTHEAST OREGON AND
SOUTHEAST WASHINGTON THROUGH SATURDAY MORNING SO HAVE BUMPED UP POPS
FOR THIS. OTHERWISE SATURDAY WILL BE AN IN BETWEEN WEATHER SYSTEMS
DAY BEFORE THE NEXT UPPER LEVEL LOW DROPS INTO THE PACIFIC NORTHWEST
LATE SUNDAY. THIS WILL ONCE AGAIN INCREASE SHOWERS AND BRING A
POSSIBILITY SOME THUNDERSTORMS TO PORTIONS OF THE FORECAST AREA.
THERE WILL ALSO BE SOME INCREASING WESTERLY WINDS FRIDAY AND THROUGH
THE WEEKEND USHERING IN SOME COOLER AIR. SNOW LEVELS WILL BE
DROPPING TO 5000 TO 6000 FEET ON FRIDAY NIGHT AND THEN DOWN TO 4000
TO 5000 FEET ON SUNDAY.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...A LARGE UPPER LOW WILL
BE MOVING SOUTHEAST ACROSS OREGON ON SUNDAY NIGHT. THIS WILL BRING A
GOOD CHANCE OF SHOWERS AND HIGH MOUNTAIN SNOW SHOWERS TO THE AREA.
ON MONDAY THE LOW WILL BE OVER THE GREAT BASIN BUT WRAP AROUND
MOISTURE ESPECIALLY IN OREGON WILL BRING A CONTINUED CHANCE FOR
SHOWERS AND MOUNTAIN SNOW SHOWERS ABOVE 4000-4500 FEET. WITH THE LOW
OVER THE CENTRAL ROCKIES ON TUESDAY AND SLIGHT RIDGING OVER THE AREA
EXPECT A DECREASE IN SHOWER ACTIVITY. BY WEDNESDAY ANOTHER UPPER LOW
WILL EITHER MOVE OVER OR JUST SOUTH OF THE REGION WITH INCREASING
CHANCES FOR SHOWERS. BY THURSDAY SHOWERS WILL BEGIN TO TAPER OFF.
THERE MAY BE ENOUGH INSTABILITY FOR THUNDERSTORMS WEDNESDAY AND
THURSDAY BUT THE MARGINAL NATURE OF THE THREAT SEVERAL DAYS OUT
PRECLUDES A MENTION IN THE FORECAST AT THIS TIME. IT WILL BE WINDY
THROUGH THE COLUMBIA RIVER GORGE AND KITTITAS VALLEY SUNDAY NIGHT
THROUGH MONDAY. TEMPERATURES WILL START OUT NEAR OR SLIGHTLY BELOW
NORMAL AND THEN RISE TO SLIGHTLY ABOVE NORMAL BY THE END OF THE
FORECAST PERIOD. 78
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 52 74 50 65 / 10 40 40 10
ALW 56 76 50 66 / 10 40 40 20
PSC 59 76 51 72 / 10 20 20 10
YKM 52 74 47 71 / 20 30 20 10
HRI 53 76 51 68 / 10 20 20 10
ELN 51 73 49 65 / 20 40 20 10
RDM 41 62 37 60 / 10 60 40 10
LGD 46 70 44 58 / 20 60 60 30
GCD 47 67 44 58 / 10 70 60 10
DLS 52 69 50 65 / 20 40 20 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
83/94
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
644 PM EDT FRI APR 22 2016
.SYNOPSIS...
A COLD FRONT WILL PUSH THROUGH PA THIS EVENING AND EARLY TONIGHT.
HIGH PRESSURE WILL BUILD INTO THE REGION THIS WEEKEND. ANOTHER
COLD FRONT IS LIKELY TO PUSH ACROSS THE AREA MONDAY NIGHT INTO
TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
WIND SHIFT TO THE NW AT KBFD AND KFKL IN THE LAST HR. SO THE FRONT
MUST BE PUSHING THRU THERE NOW.
HRRR AND RAP NOT HANDLING THE INITIAL AND FIRST HR/TWO OF
QPF AND PLACEMENT OF CONVECTION VERY WELL THIS EVENING. THIS MAY
BE DUE TO THE LIGHT RADAR RETURNS WITH MID CLOUDS AHEAD OF THE
MAIN AREA OF SCT SHRA BEING INGESTED INTO THE MODEL INITS. SHOWERS
IN THE NORTH ARE UNDERDONE AND IN THE SOUTH ARE OVERDONE. IN ANY
CASE...THE SHOWERS ARE MOVING SLOWLY...BUT THE RADAR ESTIMATES ARE
VERY LOW SAVE FOR SOME PINPRICKS OF >0.25IN IN THE THE ONE HR
ESTIMATES. PWATS ARE NOT THAT HIGH...AND ARE ONLY A LITTLE HIGHER
THAN NORMAL FOR LATE APRIL. VERY LITTLE ICE IN THEM AND THUS
LITTLE LIGHTNING. JUST ENOUGH LTG TO KEEP MENTIONS OF IT IN THE
FCST. WILL CARRY ON WITH HIGH POPS IN THE SE FOR THE LATE EVENING
AND EARLY TONIGHT.
PREV...
A DISTINCT AREA OF LLVL RIDGING HELPED TO BRING MAINLY DRY
CONDITIONS ACROSS MUCH OF CENTRAL PENN TODAY BENEATH AN OVC LAYER
OF THICK ALTO CU AND ALTO/CIRROSTRATUS CLOUDS. AN AREA OF SHOWERS
LINKED TO THE NOSE OF A 30-40 KT SWRLY LLJ WAS SLIDING ACROSS OUR
EXTREME SERN COUNTIES ATTM...WHILE A SECOND AREA OF SCATTERED
SHOWERS /ASSOCIATED WITH THE LEFT EXIT REGION OF A SOUTHERLY UPPER
JETLET JUST AHEAD OF THE SFC COLD FRONT/ WAS AFFECTING THE NRN
MTNS AND WRN PLATEAU OF PENN..
MIXED LAYER CAPE WILL INCREASE TO 200-500 J/KG ACROSS SOUTHERN AND
WESTERN PARTS OF THE FCST AREA LATE THIS AFTERNOON AND
EVENING /WITH SOME POCKETS OF CAPE APPROACHING 1000 J/KG
POSSIBLE/. THIS MODEST INCREASE IN INSTAB AHEAD OF THE COLD FRONT
WILL SUPPORT THE DEVELOPMENT OF ISOLATED HEAVIER SHOWERS AND A
FEW LOW-TOPPED TSRA...MAINLY NEAR AND WEST OF RT 219 AND TO THE
SOUTH OF THE RT 22/322 CORRIDOR.
TEMPS AT 18Z ARE NEARING THEIR FORECAST HIGHS /SEVERAL DEG ABV
CLIMO/...IN THE LOWER TO MID 60S ACROSS THE NRN AND WRN MTNS...AND
UPPER 60S TO LOWER 70S ELSEWHERE ACROSS CENTRAL AND SERN PA.
AS THE COLD FRONT SLIDES SE ACROSS THE ALLEGHENIES AND INTO
CENTRAL PENN LATER THIS EVENING THROUGH ABOUT 06Z...THE TIMING
SHOULD COINCIDE NICELY WITH THE EWD PROGRESSION OF AN AREA OF
STRONG UPPER DIFFLUENCE/UVVEL JUST AHEAD OF THE COMPACT UPPER
TROUGH SEEN OVER OHIO LATE THIS AFTERNOON. HRRR AGREES WITH THIS
SCENARIO AND PAINTS OF FEW SMALL AREAS OF ENHANCED CONVECTION AND
QPF OVER THE SOUTHERN HALF TO TWO THIRDS OF THE CWA. ALTHOUGH A
FEW RUMBLES OF THUNDER CAN/T BE RULED OUT...SCATTERED MDT TO
BRIEFLY HEAVY SHRA WILL LIKELY BE THE DOMINANT FORM OF CONVECTION
THIS EVENING AND TONIGHT. ADDITIONAL RAINFALL RANGING FROM 1-2
TENTHS ACROSS THE REGION NORTH OF I-80...AND UP TO 3 TENTHS OF AN
INCH IN THE SOUTH STILL LOOKS IN GOOD SHAPE FORECAST-WISE BASED ON
THE PAST SEVERAL RUNS OF THE HRRR...THE LATEST SREF AND GEFS...AND
12Z OPER MODELS.
WINDS WILL BE VERY LIGHT AND VARIABLE IN DIRECTION TO START THE
AFTERNOON...THEN BECOME SOUTHWESTERLY AT 5 TO 8 KTS LATER THIS
AFTERNOON/EVENING JUST AHEAD OF THE CFRONT.
AFTER THE CFROPA LATE TONIGHT AND EARLY SATURDAY...LLVL WINDS WILL
BLOW FROM 340-010 DEG...WITH SOME GUSTS INTO THE MID AND UPPER
TEENS BY LATE SAT MORNING. A PERIOD OF LOW STRATUS/STRATOCU
APPEARS LIKELY LATE TONIGHT THROUGH 14-16Z SAT /ESP ACROSS THE
NRN AND WRN MTNS OF PENN/.
LOW TEMPS EARLY SATURDAY WILL VARY FROM THE U30S NW TO LOWER 50S
IN THE SE.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
CAN/T RULE OUT A FEW LINGERING SHOWERS LASTING THRU LATE SAT AM
ACROSS THE LOWER SUSQ VALLEY. THE MAIN FCST PROBLEM FOR LATER
SATURDAY MORNING WILL SURROUND THE EXTENT OF LOW CLOUDS...AND
TIMING OF THEIR DISSIPATION.
THE ARRIVAL OF HIGH PRESSURE AND DRIER NNW FLOW SHOULD BRING
MSUNNY SKIES TO THE ENTIRE AREA BY SAT AFTN. SUPERBLEND TEMPS
LOOKING SEASONABLE SAT...FROM THE U50S NW MTNS TO M-U60S SE
COUNTIES.
THE WIND WILL AVERAGE 10-15 KTS WITH SOME GUSTS IN THE UPPER TEENS
LIKELY CENTRAL AND WESTERN PENN. SUSTAINED AND PEAK GUSTS
NORTHERLY WIND GUSTS COULD BE 5-8 KTS HIGHER ACROSS THE EAST
WHERE LLVL P-GRADIENT IS THE TIGHTEST AHEAD OF HIGH PRESSURE OVER
THE GLAKES REGION. LATER SHIFTS MAY HAVE TO CONSIDER/COLLABORATE
WITH SURROUNDING WFOS A FIRE WEATHER WATCH OR RED FLAG WARNING FOR
SATURDAY SHOULD RAINFALL AMOUNTS BE LESS THAN CURRENTLY FCST.
HIGH PRESSURE WILL BECOME CENTERED OVER THE REGION SATURDAY NIGHT
WITH CLEAR SKIES...LOW PWATS AND NEARLY CALM AIR. INCLUDED PATCHY
FROST ACROSS THE MTNS NEAR THE I-80 CORRIDOR AND LARGER AREAS OF
FROST ACROSS THE NRN MTNS. HOWEVER...THIS AREA OF THE STATE IS
STILL OUTSIDE OF THE BEGINNING OF THE GROWING SEASON. A LOW PROB
FOR A FROST ADVISORY IS IN THE EAST/WEST SLIVER OF COUNTIES JUST
ALONG AND JUST SOUTH OF I-80 WHERE THE OFFICIAL START TO THE
GROWING SEASON WAS THURSDAY/APRIL 21ST.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
GUIDANCE HAS BEEN CONSISTENT IN SHOWING THE BROAD
TROUGH/RIDGE/TROUGH CONFIGURATION EXTENDING FROM THE GREAT BASIN
TO THE PLAINS INTO THE MID ATLANTIC REGION AT THE START OF THE
LONG TERM PERIOD TRANSITIONING TOWARD A MEAN WESTERN
TROUGH/BUILDING RIDGE IN THE EAST THRU NEXT WEEK. UNCERTAINTY HAS
ALSO DECREASED OVER THE POSITION OF AN EAST/WEST SFC FRONTAL
BOUNDARY AND LOW LEVEL BAROCLINIC ZONE WITH COLDER TEMPERATURES
STAYING WELL TO THE NORTH OF PA ALONG THE NRN TIER STATES/CANADIAN
BORDER.
THE WEEKEND AS A WHOLE LOOKS FAIR AND DRY WITH A RISK OF
FROST/FREEZE CONDITIONS SATURDAY NIGHT INTO SUNDAY MORNING. WAVES
OF LOW PRESSURE MOVG EWD ALONG WAVY SFC FRONTAL BOUNDARY PRESSING
SWD FROM THE LOWER LAKES/UPSTATE NY SHOULD BRING PERIODS OF RAIN
EARLY NEXT WEEK BUT CONFIDENCE IN EXACT TIMING OF GREATEST PCPN
RISK IS STILL BELOW AVERAGE AND COULD EASILY SHIFT +/- 12 HOURS.
MODEL CONSENSUS FAVORS A DRY PERIOD ON WEDNESDAY BEFORE RAIN PROBS
TREND HIGHER FROM WEST TO EAST INTO THE SECOND HALF OF NEXT WEEK.
ASIDE FROM A CHILLY SUNDAY MORNING...THE GLOBAL ENSEMBLE MEANS
ALONG WITH NATIONAL/REGIONAL BLENDS ALL SUPPORT ABOVE NORMAL TEMPS
THROUGH THE MEDIUM RANGE PERIOD.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
COLD FRONT WILL PUSH SLOWLY ACROSS THE REGION LATER TODAY AND
TONIGHT. AHEAD OF THAT...LLJET WILL SWING THROUGH THE SOUTHEASTERN
THIRD OF THE STATE...BRINGING A PLUME OF MOISTURE THROUGH EARLY
THIS AFTERNOON...THAT WILL SUPPORT A FEW AREA OF MAINLY LIGHT
SHOWERS AND BRING CIG REDUCTIONS MAINLY TO WESTERN HALF.
THE AREA OF DRYING AND MAINLY VFR...MID-LEVEL CLOUDS THAT
OCCURRED BEHIND THE DEPARTING LL JET OVER NRN MD AND SERN PENN
WILL TRANSITION TO AN INCREASING THREAT FOR SHOWERS OVER THE WRN
MTNS AFTER 20Z.
THE COLD FRONT AND APPROACHING UPPER LOW WILL BRING NUMEROUS
SHOWERS AND PERHAPS A FEW ISOLATED LATE TODAY/ THIS EVENING
/AND MAINLY OVERNIGHT IN THE SE/...ALONG WITH RESTRICTIONS
RETURNING TO THE WEST AND INTERMITTENT RESTRICTIONS TO THE EAST.
RESTRICTIONS CONTINUE OVER WESTERN AND CENTRAL MTNS INTO SAT AS
UPPER TROUGH PASSES THROUGH.
OUTLOOK...
SAT...AM LOW CIGS W MTNS.
SUN...NO SIG WX EXPECTED.
MON-TUE...PM SHRA DEVELOPING MONDAY AND CONTINUING INTO TUESDAY.
REDUCTIONS POSSIBLE...MAINLY NW PA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/GARTNER
AVIATION...LAMBERT/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
330 PM EDT FRI APR 22 2016
.SYNOPSIS...
A COLD FRONT ALONG THE SOUTH SHORE OF LAKE ERIE THIS AFTERNOON
WILL PUSH SLOWLY SOUTHEAST ACROSS PENNSYLVANIA LATE TODAY AND
TONIGHT. THIS FRONT WILL COMBINE WITH A COMPACT UPPER LOW HEADING
EAST FROM OHIO TO BRING AN INCREASING CHANCE FOR SHOWERS LATER
THIS AFTERNOON AND EVENING ACROSS CENTRAL AND WESTERN
PENNSYLVANIA...AND LATE TONIGHT OVER THE SOUTHEAST. HIGH PRESSURE
WILL BUILD INTO THE REGION THIS WEEKEND. ANOTHER COLD FRONT IS
LIKELY TO PUSH ACROSS THE AREA MONDAY NIGHT INTO TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
A DISTINCT AREA OF LLVL RIDGING HELPED TO BRING MAINLY DRY
CONDITIONS ACROSS MUCH OF CENTRAL PENN TODAY BENEATH AN OVC LAYER
OF THICK ALTO CU AND ALTO/CIRROSTRATUS CLOUDS. AN AREA OF SHOWERS
LINKED TO THE NOSE OF A 30-40 KT SWRLY LLJ WAS SLIDING ACROSS OUR
EXTREME SERN COUNTIES ATTM...WHILE A SECOND AREA OF SCATTERED
SHOWERS /ASSOCIATED WITH THE LEFT EXIT REGION OF A SOUTHERLY UPPER
JETLET JUST AHEAD OF THE SFC COLD FRONT/ WAS AFFECTING THE NRN
MTNS AND WRN PLATEAU OF PENN..
MIXED LAYER CAPE WILL INCREASE TO 200-500 J/KG ACROSS SOUTHERN AND
WESTERN PARTS OF THE FCST AREA LATE THIS AFTERNOON AND
EVENING /WITH SOME POCKETS OF CAPE APPROACHING 1000 J/KG
POSSIBLE/. THIS MODEST INCREASE IN INSTAB AHEAD OF THE COLD FRONT
WILL SUPPORT THE DEVELOPMENT OF ISOLATED HEAVIER SHOWERS AND A
FEW LOW-TOPPED TSRA...MAINLY NEAR AND WEST OF RT 219 AND TO THE
SOUTH OF THE RT 22/322 CORRIDOR.
TEMPS AT 18Z ARE NEARING THEIR FORECAST HIGHS /SEVERAL DEG ABV
CLIMO/...IN THE LOWER TO MID 60S ACROSS THE NRN AND WRN MTNS...AND
UPPER 60S TO LOWER 70S ELSEWHERE ACROSS CENTRAL AND SERN PA.
AS THE COLD FRONT SLIDES SE ACROSS THE ALLEGHENIES AND INTO
CENTRAL PENN LATER THIS EVENING THROUGH ABOUT 06Z...THE TIMING
SHOULD COINCIDE NICELY WITH THE EWD PROGRESSION OF AN AREA OF
STRONG UPPER DIFFLUENCE/UVVEL JUST AHEAD OF THE COMPACT UPPER
TROUGH SEEN OVER OHIO LATE THIS AFTERNOON. HRRR AGREES WITH THIS
SCENARIO AND PAINTS OF FEW SMALL AREAS OF ENHANCED CONVECTION AND
QPF OVER THE SOUTHERN HALF TO TWO THIRDS OF THE CWA. ALTHOUGH A
FEW RUMBLES OF THUNDER CAN/T BE RULED OUT...SCATTERED MDT TO
BRIEFLY HEAVY SHRA WILL LIKELY BE THE DOMINANT FORM OF CONVECTION
THIS EVENING AND TONIGHT. ADDITIONAL RAINFALL RANGING FROM 1-2
TENTHS ACROSS THE REGION NORTH OF I-80...AND UP TO 3 TENTHS OF AN
INCH IN THE SOUTH STILL LOOKS IN GOOD SHAPE FORECAST-WISE BASED ON
THE PAST SEVERAL RUNS OF THE HRRR...THE LATEST SREF AND GEFS...AND
12Z OPER MODELS.
WINDS WILL BE VERY LIGHT AND VARIABLE IN DIRECTION TO START THE
AFTERNOON...THEN BECOME SOUTHWESTERLY AT 5 TO 8 KTS LATER THIS
AFTERNOON/EVENING JUST AHEAD OF THE CFRONT.
AFTER THE CFROPA LATE TONIGHT AND EARLY SATURDAY...LLVL WINDS WILL
BLOW FROM 340-010 DEG...WITH SOME GUSTS INTO THE MID AND UPPER
TEENS BY LATE SAT MORNING. A PERIOD OF LOW STRATUS/STRATOCU
APPEARS LIKELY LATE TONIGHT THROUGH 14-16Z SAT /ESP ACROSS THE
NRN AND WRN MTNS OF PENN/.
LOW TEMPS EARLY SATURDAY WILL VARY FROM THE U30S NW TO LOWER 50S
IN THE SE.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
CAN/T RULE OUT A FEW LINGERING SHOWERS LASTING THRU LATE SAT AM
ACROSS THE LOWER SUSQ VALLEY. THE MAIN FCST PROBLEM FOR LATER
SATURDAY MORNING WILL SURROUND THE EXTENT OF LOW CLOUDS...AND
TIMING OF THEIR DISSIPATION.
THE ARRIVAL OF HIGH PRESSURE AND DRIER NNW FLOW SHOULD BRING
MSUNNY SKIES TO THE ENTIRE AREA BY SAT AFTN. SUPERBLEND TEMPS
LOOKING SEASONABLE SAT...FROM THE U50S NW MTNS TO M-U60S SE
COUNTIES.
THE WIND WILL AVERAGE 10-15 KTS WITH SOME GUSTS IN THE UPPER TEENS
LIKELY CENTRAL AND WESTERN PENN. SUSTAINED AND PEAK GUSTS
NORTHERLY WIND GUSTS COULD BE 5-8 KTS HIGHER ACROSS THE EAST
WHERE LLVL P-GRADIENT IS THE TIGHTEST AHEAD OF HIGH PRESSURE OVER
THE GLAKES REGION. LATER SHIFTS MAY HAVE TO CONSIDER/COLLABORATE
WITH SURROUNDING WFOS A FIRE WEATHER WATCH OR RED FLAG WARNING FOR
SATURDAY SHOULD RAINFALL AMOUNTS BE LESS THAN CURRENTLY FCST.
HIGH PRESSURE WILL BECOME CENTERED OVER THE REGION SATURDAY NIGHT
WITH CLEAR SKIES...LOW PWATS AND NEARLY CALM AIR. INCLUDED PATCHY
FROST ACROSS THE MTNS NEAR THE I-80 CORRIDOR AND LARGER AREAS OF
FROST ACROSS THE NRN MTNS. HOWEVER...THIS AREA OF THE STATE IS
STILL OUTSIDE OF THE BEGINNING OF THE GROWING SEASON. A LOW PROB
FOR A FROST ADVISORY IS IN THE EAST/WEST SLIVER OF COUNTIES JUST
ALONG AND JUST SOUTH OF I-80 WHERE THE OFFICIAL START TO THE
GROWING SEASON WAS THURSDAY/APRIL 21ST.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
GUIDANCE HAS BEEN CONSISTENT IN SHOWING THE BROAD
TROUGH/RIDGE/TROUGH CONFIGURATION EXTENDING FROM THE GREAT BASIN
TO THE PLAINS INTO THE MID ATLANTIC REGION AT THE START OF THE
LONG TERM PERIOD TRANSITIONING TOWARD A MEAN WESTERN
TROUGH/BUILDING RIDGE IN THE EAST THRU NEXT WEEK. UNCERTAINTY HAS
ALSO DECREASED OVER THE POSITION OF AN EAST/WEST SFC FRONTAL
BOUNDARY AND LOW LEVEL BAROCLINIC ZONE WITH COLDER TEMPERATURES
STAYING WELL TO THE NORTH OF PA ALONG THE NRN TIER STATES/CANADIAN
BORDER.
THE WEEKEND AS A WHOLE LOOKS FAIR AND DRY WITH A RISK OF
FROST/FREEZE CONDITIONS SATURDAY NIGHT INTO SUNDAY MORNING. WAVES
OF LOW PRESSURE MOVG EWD ALONG WAVY SFC FRONTAL BOUNDARY PRESSING
SWD FROM THE LOWER LAKES/UPSTATE NY SHOULD BRING PERIODS OF RAIN
EARLY NEXT WEEK BUT CONFIDENCE IN EXACT TIMING OF GREATEST PCPN
RISK IS STILL BELOW AVERAGE AND COULD EASILY SHIFT +/- 12 HOURS.
MODEL CONSENSUS FAVORS A DRY PERIOD ON WEDNESDAY BEFORE RAIN PROBS
TREND HIGHER FROM WEST TO EAST INTO THE SECOND HALF OF NEXT WEEK.
ASIDE FROM A CHILLY SUNDAY MORNING...THE GLOBAL ENSEMBLE MEANS
ALONG WITH NATIONAL/REGIONAL BLENDS ALL SUPPORT ABOVE NORMAL TEMPS
THROUGH THE MEDIUM RANGE PERIOD.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
COLD FRONT WILL PUSH SLOWLY ACROSS THE REGION LATER TODAY AND
TONIGHT. AHEAD OF THAT...LLJET WILL SWING THROUGH THE SOUTHEASTERN
THIRD OF THE STATE...BRINGING A PLUME OF MOISTURE THROUGH EARLY
THIS AFTERNOON...THAT WILL SUPPORT A FEW AREA OF MAINLY LIGHT
SHOWERS AND BRING CIG REDUCTIONS MAINLY TO WESTERN HALF.
THE AREA OF DRYING AND MAINLY VFR...MID-LEVEL CLOUDS THAT
OCCURRED BEHIND THE DEPARTING LL JET OVER NRN MD AND SERN PENN
WILL TRANSITION TO AN INCREASING THREAT FOR SHOWERS OVER THE WRN
MTNS AFTER 20Z.
THE COLD FRONT AND APPROACHING UPPER LOW WILL BRING NUMEROUS
SHOWERS AND PERHAPS A FEW ISOLATED LATE TODAY/ THIS EVENING
/AND MAINLY OVERNIGHT IN THE SE/...ALONG WITH RESTRICTIONS
RETURNING TO THE WEST AND INTERMITTENT RESTRICTIONS TO THE EAST.
RESTRICTIONS CONTINUE OVER WESTERN AND CENTRAL MTNS INTO SAT AS
UPPER TROUGH PASSES THROUGH.
OUTLOOK...
SAT...AM LOW CIGS W MTNS.
SUN...NO SIG WX EXPECTED.
MON-TUE...PM SHRA DEVELOPING MONDAY AND CONTINUING INTO TUESDAY.
REDUCTIONS POSSIBLE...MAINLY NW PA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/GARTNER
AVIATION...LAMBERT/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
253 PM EDT FRI APR 22 2016
.SYNOPSIS...
A COLD FRONT ALONG THE SOUTH SHORE OF LAKE ERIE THIS AFTERNOON
WILL PUSH SLOWLY SOUTHEAST ACROSS PENNSYLVANIA LATE TODAY AND
TONIGHT. THIS FRONT WILL COMBINE WITH A COMPACT UPPER LOW HEADING
EAST FROM OHIO TO BRING AN INCREASING CHANCE FOR SHOWERS LATER
THIS AFTERNOON AND EVENING ACROSS CENTRAL AND WESTERN
PENNSYLVANIA...AND LATE TONIGHT OVER THE SOUTHEAST. HIGH PRESSURE
WILL BUILD INTO THE REGION THIS WEEKEND. ANOTHER COLD FRONT IS
LIKELY TO PUSH ACROSS THE AREA MONDAY NIGHT INTO TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
A DISTINCT AREA OF LLVL RIDGING HELPED TO BRING MAINLY DRY
CONDITIONS ACROSS MUCH OF CENTRAL PENN TODAY BENEATH AN OVC LAYER
OF THICK ALTO CU AND ALTO/CIRROSTRATUS CLOUDS. AN AREA OF SHOWERS
LINKED TO THE NOSE OF A 30-40 KT SWRLY LLJ WAS SLIDING ACROSS OUR
EXTREME SERN COUNTIES ATTM...WHILE A SECOND AREA OF SCATTERED
SHOWERS /ASSOCIATED WITH THE LEFT EXIT REGION OF A SOUTHERLY UPPER
JETLET JUST AHEAD OF THE SFC COLD FRONT/ WAS AFFECTING THE NRN
MTNS AND WRN PLATEAU OF PENN..
MIXED LAYER CAPE WILL INCREASE TO 200-500 J/KG ACROSS SOUTHERN AND
WESTERN PARTS OF THE FCST AREA LATE THIS AFTERNOON AND
EVENING /WITH SOME POCKETS OF CAPE APPROACHING 1000 J/KG
POSSIBLE/. THIS MODEST INCREASE IN INSTAB AHEAD OF THE COLD FRONT
WILL SUPPORT THE DEVELOPMENT OF ISOLATED HEAVIER SHOWERS AND A
FEW LOW-TOPPED TSRA...MAINLY NEAR AND WEST OF RT 219 AND TO THE
SOUTH OF THE RT 22/322 CORRIDOR.
TEMPS AT 18Z ARE NEARING THEIR FORECAST HIGHS /SEVERAL DEG ABV
CLIMO/...IN THE LOWER TO MID 60S ACROSS THE NRN AND WRN MTNS...AND
UPPER 60S TO LOWER 70S ELSEWHERE ACROSS CENTRAL AND SERN PA.
AS THE COLD FRONT SLIDES SE ACROSS THE ALLEGHENIES AND INTO
CENTRAL PENN LATER THIS EVENING THROUGH ABOUT 06Z...THE TIMING
SHOULD COINCIDE NICELY WITH THE EWD PROGRESSION OF AN AREA OF
STRONG UPPER DIFFLUENCE/UVVEL JUST AHEAD OF THE COMPACT UPPER
TROUGH SEEN OVER OHIO LATE THIS AFTERNOON. HRRR AGREES WITH THIS
SCENARIO AND PAINTS OF FEW SMALL AREAS OF ENHANCED CONVECTION AND
QPF OVER THE SOUTHERN HALF TO TWO THIRDS OF THE CWA. ALTHOUGH A
FEW RUMBLES OF THUNDER CAN/T BE RULED OUT...SCATTERED MDT TO
BRIEFLY HEAVY SHRA WILL LIKELY BE THE DOMINANT FORM OF CONVECTION
THIS EVENING AND TONIGHT. ADDITIONAL RAINFALL RANGING FROM 1-2
TENTHS ACROSS THE REGION NORTH OF I-80...AND UP TO 3 TENTHS OF AN
INCH IN THE SOUTH STILL LOOKS IN GOOD SHAPE FORECAST-WISE BASED ON
THE PAST SEVERAL RUNS OF THE HRRR...THE LATEST SREF AND GEFS...AND
12Z OPER MODELS.
WINDS WILL BE VERY LIGHT AND VARIABLE IN DIRECTION TO START THE
AFTERNOON...THEN BECOME SOUTHWESTERLY AT 5 TO 8 KTS LATER THIS
AFTERNOON/EVENING JUST AHEAD OF THE CFRONT.
AFTER THE CFROPA LATE TONIGHT AND EARLY SATURDAY...LLVL WINDS WILL
BLOW FROM 340-010 DEG...WITH SOME GUSTS INTO THE MID AND UPPER
TEENS BY LATE SAT MORNING. A PERIOD OF LOW STRATUS/STRATOCU
APPEARS LIKELY LATE TONIGHT THROUGH 14-16Z SAT /ESP ACROSS THE
NRN AND WRN MTNS OF PENN/.
LOW TEMPS EARLY SATURDAY WILL VARY FROM THE U30S NW TO LOWER 50S
IN THE SE.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
CAN/T RULE OUT A FEW LINGERING SHOWERS LASTING THRU LATE SAT AM
ACROSS THE LOWER SUSQ VALLEY. THE MAIN FCST PROBLEM FOR LATER
SATURDAY MORNING WILL SURROUND THE EXTENT OF LOW CLOUDS...AND
TIMING OF THEIR DISSIPATION.
THE ARRIVAL OF HIGH PRESSURE AND DRIER NNW FLOW SHOULD BRING
MSUNNY SKIES TO THE ENTIRE AREA BY SAT AFTN. SUPERBLEND TEMPS
LOOKING SEASONABLE SAT...FROM THE U50S NW MTNS TO M-U60S SE
COUNTIES.
THE WIND WILL AVERAGE 10-15 KTS WITH SOME GUSTS IN THE UPPER TEENS
LIKELY CENTRAL AND WESTERN PENN. SUSTAINED AND PEAK GUSTS
NORTHERLY WIND GUSTS COULD BE 5-8 KTS HIGHER ACROSS THE EAST
WHERE LLVL P-GRADIENT IS THE TIGHTEST AHEAD OF HIGH PRESSURE OVER
THE GLAKES REGION. LATER SHIFTS MAY HAVE TO CONSIDER/COLLABORATE
WITH SURROUNDING WFOS A FIRE WEATHER WATCH OR RED FLAG WARNING FOR
SATURDAY SHOULD RAINFALL AMOUNTS BE LESS THAN CURRENTLY FCST.
HIGH PRESSURE WILL BECOME CENTERED OVER THE REGION SATURDAY NIGHT
WITH CLEAR SKIES...LOW PWATS AND NEARLY CALM AIR. INCLUDED PATCHY
FROST ACROSS THE MTNS NEAR THE I-80 CORRIDOR AND LARGER AREAS OF
FROST ACROSS THE NRN MTNS. HOWEVER...THIS AREA OF THE STATE IS
STILL OUTSIDE OF THE BEGINNING OF THE GROWING SEASON. A LOW PROB
FOR A FROST ADVISORY IS IN THE EAST/WEST SLIVER OF COUNTIES JUST
ALONG AND JUST SOUTH OF I-80 WHERE THE OFFICIAL START TO THE
GROWING SEASON WAS THURSDAY/APRIL 21ST.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
GUIDANCE HAS COME INTO MUCH BETTER AGREEMENT IN THE PATTERN
VERSUS PREVIOUS DAYS...SHOWING A MIGRATION FROM A BROAD
TROUGH/RIDGE/TROUGH CONFIGURATION EXTENDING FROM THE GREAT BASIN
TO THE PLAINS INTO THE MID ATLANTIC REGION AT THE START OF THE
PERIOD...TOWARD A MEAN WESTERN TROUGH/BUILDING RIDGE IN THE EAST
BY NEXT THU AS THE STRONG HIGH LATITUDE BLOCKING WEAKENS OVER
GREENLAND/EASTERN CANADA. UNCERTAINTY HAS ALSO DECREASED OVER THE
POSITION OF AN EAST/WEST SFC FRONTAL BOUNDARY AND LOW LEVEL
BAROCLINIC ZONE WITH COLDER TEMPERATURES STAYING WELL TO THE NORTH
OF PA ALONG THE NRN TIER STATES/CANADIAN BORDER.
THE WEEKEND AS A WHOLE LOOKS FAIR AND DRY WITH A RISK OF
FROST/FREEZE CONDITIONS SATURDAY NIGHT INTO SUNDAY MORNING. WAVES
OF LOW PRESSURE MOVG EWD ALONG WAVY SFC FRONTAL BOUNDARY PRESSING
SWD FROM THE LOWER LAKES/UPSTATE NY SHOULD BRING PERIODS OF RAIN
EARLY NEXT WEEK BUT CONFIDENCE IN EXACT TIMING OF GREATEST PCPN
RISK IS STILL BELOW AVERAGE AND COULD EASILY SHIFT +/- 12 HOURS.
MODEL CONSENSUS FAVORS A DRY PERIOD ON WEDNESDAY BEFORE RAIN PROBS
TREND HIGHER FROM WEST TO EAST INTO THE SECOND HALF OF NEXT WEEK.
ASIDE FROM A CHILLY SUNDAY MORNING...THE GLOBAL ENSEMBLE MEANS
ALONG WITH NATIONAL/REGIONAL BLENDS ALL SUPPORT ABOVE NORMAL TEMPS
THROUGH THE MEDIUM RANGE PERIOD.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
COLD FRONT WILL PUSH SLOWLY ACROSS THE REGION LATER TODAY AND
TONIGHT. AHEAD OF THAT...LLJET WILL SWING THROUGH THE SOUTHEASTERN
THIRD OF THE STATE...BRINGING A PLUME OF MOISTURE THROUGH EARLY
THIS AFTERNOON...THAT WILL SUPPORT A FEW AREA OF MAINLY LIGHT
SHOWERS AND BRING CIG REDUCTIONS MAINLY TO WESTERN HALF.
THE AREA OF DRYING AND MAINLY VFR...MID-LEVEL CLOUDS THAT
OCCURRED BEHIND THE DEPARTING LL JET OVER NRN MD AND SERN PENN
WILL TRANSITION TO AN INCREASING THREAT FOR SHOWERS OVER THE WRN
MTNS AFTER 20Z.
THE COLD FRONT AND APPROACHING UPPER LOW WILL BRING NUMEROUS
SHOWERS AND PERHAPS A FEW ISOLATED LATE TODAY/ THIS EVENING
/AND MAINLY OVERNIGHT IN THE SE/...ALONG WITH RESTRICTIONS
RETURNING TO THE WEST AND INTERMITTENT RESTRICTIONS TO THE EAST.
RESTRICTIONS CONTINUE OVER WESTERN AND CENTRAL MTNS INTO SAT AS
UPPER TROUGH PASSES THROUGH.
OUTLOOK...
SAT...AM LOW CIGS W MTNS.
SUN...NO SIG WX EXPECTED.
MON-TUE...PM SHRA DEVELOPING MONDAY AND CONTINUING INTO TUESDAY.
REDUCTIONS POSSIBLE...MAINLY NW PA.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...LAMBERT/RXR
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
636 PM CDT SAT APR 23 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 418 PM CDT SAT APR 23 2016
WARM AND WINDY DAY TODAY TO BE FOLLOWED BY A MILD AND BREEZY NIGHT
AS SOUTHERLY FLOW REMAINS STOUT BENEATH INCREASING LOW LEVEL JET.
QUESTION FOR TONIGHT WILL BE MOISTURE AVAILABILITY FOR CONVERGENT
AREA ON THE NOSE OF THE LOW LEVEL JET. PERSISTENT BUT WEAKENING WARM
ADVECTION WILL AID IN STEEPENING MID LEVEL LAPSE RATES ACROSS THE
AREA...AND WITH SOME MODEST MID LEVEL MOISTURE AVAILABLE...POTENTIAL
FOR SPOTTY ACCAS SHRA/TSRA OVER MUCH OF THE CWA BY LATE TONIGHT.
THINK MORE FOCUSED AREA WILL BE NEAR/NORTH OF HIGHWAY 14...NEAREST
THE NOSE OF THE LOW LEVEL JET/850MB WARM FRONT...BUT EVEN THERE
CONFIDENCE NOT HIGH ENOUGH IN MEASURABLE PRECIP THREAT AT THIS TIME
TO GO MUCH HIGHER THAN SLIGHT CHANCE POPS AFTER 06Z...WITH BETTER
CHANCE NORTH OF OUR FORECAST AREA. STEADY SOUTHERLY BREEZE AND
MODEST LOW LEVEL MOISTURE SHOULD HOLD OVERNIGHT LOWS IN THE MID 50S
TO AROUND 60.
ANY EARLY MORNING ACCAS ACTIVITY LIKELY TO WANE AS THE LOW LEVEL JET
WEAKENS THROUGH THE MORNING...AND FOCUS THEN SHIFTS TO DETERMINING
JUST HOW FAR EAST THE DEVELOPING DRY LINE WILL PROGRESS THROUGH THE
AFTERNOON. QUITE A BIT OF DISAGREEMENT AMONG THE MODELS ON EVENTUAL
PLACEMENT...THOUGH OVERALL HAVE TRENDED A BIT FARTHER WEST WITH THIS
FEATURE OVER RECENT RUNS. NAM MUCH FARTHER WEST THAN MOST MODELS...
HOLDING THE DRY LINE WEST OF THE JAMES RIVER VALLEY THROUGH 00Z...
WHILE GFS MORE AGGRESSIVE IN PUSHING THE DRY LINE NEAR/EAST OF I-29
BY 21Z BEFORE PULLING IT BACK TO THE WEST AS A SURFACE LOW BECOMES
MORE ORGANIZED IN SOUTH CENTRAL SOUTH DAKOTA. HIGHER-RESOLUTION
ARW/NMM MODELS APPEAR A GOOD COMPROMISE WITH A LOCATION NEAR/JUST
WEST OF I-29 IN THE LATE AFTERNOON...AND HAVE FAVORED THIS SOLUTION
WHICH KEEPS BEST CHANCE FOR DEVELOPMENT EAST OF A VERMILLION-SIOUX
FALLS-BROOKINGS LINE AFTER 21Z. WITH CONTINUED STEEP MID LEVEL LAPSE
RATES...ALONG WITH LOW LEVEL DEW POINTS CLIMBING INTO THE MID-UPPER
50S AND DEEP LAYER SHEAR PUSHING 40-45KTS...CANNOT ARGUE WITH SLIGHT
RISK AS HIGHLIGHTED BY SPC ACROSS NORTHWEST IOWA. INCREASED MOISTURE
AND GREATER CLOUD COVERAGE COULD HOLD TEMPERATURES EAST OF I-29 DOWN
A BIT FROM FULL MIXING POTENTIAL...AND HAVE LOWERED HIGHS A COUPLE
OF DEGREES INTO THE MID 70S. MEANWHILE LOCATIONS WEST OF THE DRY
LINE SHOULD BE WELL-MIXED WITH HIGHS AGAIN CLOSE TO 80 DEGREES.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 418 PM CDT SAT APR 23 2016
SEVERE WEATHER THREAT WILL CONTINUE THROUGH THE EARLY EVENING HOURS.
WILL HAVE TO MONITOR POTENTIAL FOR STORMS TO BECOME A BIT MORE
THREATENING ACROSS PARTS OF NW IA...WITH MODELS INDICATING AN
INCREASE IN WINDS ABOUT A KM OR SO OFF THE SURFACE ALREADY BY EARLY
EVENING. WITH PERIOD OF MAIN PV ADVECTION LASTING INTO EARLY
EVENING...WILL MAXIMIZE POTENTIAL AROUND 00Z OR SHORTLY
THEREAFTER...AND BY 03Z LIKELY TO SEE DOWNWARD TREND IN INTENSITY
AND EASTWARD PUSH TO MAIN BROKEN LINE...FAVORED BY ORIENTATION OF
SHEAR VECTOR CROSS BOUNDARY. OTHER CONVECTION WILL BE POSSIBLE BACK
TOWARD THE CONVERGENCE AREA WANDERING THROUGH THE MID JAMES VALLEY.
WHILE A MUCH LESS LIKELY TO SUPPORT AN ISOLATED SEVERE STORM NORTH
OF I-90...IT IS CERTAINLY A NON ZERO THREAT.
AS MAIN UPPER LOW BEGINS TO SLIDE/SHEAR EAST/NORTHEASTWARD
OVERNIGHT...PRECIPITATION SHOULD WRAP/SETTLE BACK MAINLY THROUGH THE
NORTHERN HALF OF THE AREA...ROUGHLY NORTH OF I 90. SHOULD BE MAINLY
RAIN...BUT A TOUCH OF ELEVATED INSTABILITY REMAINS AHEAD OF THE WAVE
AND HAVE MAINTAINED A MENTION OF THUNDER SLIPPING EASTWARD THROUGH
THE NIGHT EAST OF I-29.
BEHIND THE SYSTEM...WILL SEE FAIRLY EXPANSIVE STRATUS SHIELD PUSH
SOUTHWARD. AS A RESULT...TEMPS WILL STRUGGLE OVER MUCH OF THE
AREA...BUT PERHAPS CLOUDS COULD SPARE PARTS OF FAR NORTHWEST IOWA
LONG ENOUGH INTO THE DAY TO HAVE TEMPS MODERATE INTO THE MID 60S.
LOCATIONS HEADING PROGRESSIVELY NORTH AND WEST WILL HAVE READINGS
MAINLY STEADY TO A MODEST CLIMB AT BEST...MOSTLY IN THE 50S...
ESPECIALLY WHERE SOME LIGHT RAIN COULD LINGER AROUND KBKX AND KMML.
PLENTY OF CLOUDS HOLDING AROUND MONDAY NIGHT...AS NORTHERLY WINDS
WORK TOWARD NORTHEAST...A TRAJECTORY IN FAVOR OF HOLDING MORE FIRM
WITH LOW CLOUD COVERAGE.
ON TUESDAY...WILL HOLD OUT HOPE THAT PERSISTENT AND TREND TO
EASTERLY FLOW WILL EVENTUALLY HELP TO BREAK OUT LOW CLOUDS AT
LEAST THROUGH SOME AREAS EAST OF I 29...BUT UNFORTUNATELY THE NEXT
SYSTEM WILL ALREADY BE TRUDGING OUT OF THE ROCKIES AND INTO THE
CENTRAL HIGH PLAINS. MEAN SOLUTIONS A BIT SLOWER THAN PREVIOUS FEW
SETS OF MODEL RUNS...AND RIDGING TO THE EAST SHOULD BE ABLE TO HOLD
OFF PRECIP TO JUST AREAS MAINLY JAMES VALLEY AND MISSOURI VALLEY
THROUGH AFTERNOON. ELEVATED INSTABILITY RETURNS WITH SOLID WARM AIR
ADVECTION IN THE MID LEVELS...AND AGAIN WILL START TO WORK THUNDER
INTO THE SOUTH LATER IN DAY.
FAIRLY CONSISTENT SOLUTIONS HANDLING PACE AND TRACK OF LARGE CLOSED
LOW THROUGH THE CENTRAL AND NORTHERN PLAINS THROUGH THURSDAY. SOME
MINOR NORTH/SOUTH VARIATIONS IN TRACK OF MID LEVEL CIRCULATION...
BUT SUGGESTION THAT AREA UNLIKELY TO FULLY BREAK INTO THE WARM
SECTOR WITH SURFACE WAVE KEEPING FURTHER SOUTH IN THE VAST MAJORITY
OF SOLUTIONS. GFS AND CANADIAN KEEP WINDOW OPEN THAT WAVE/WARM FRONT
COULD SPREAD INTO FAR NORTHEAST NEBRASKA OR NORTHWEST IOWA ON
WEDNESDAY...BUT IN GENERAL WILL BE SUSCEPTIBLE FOR PERIODS OF
SHOWERS AND THUNDERSTORMS WRAPPING AROUND THE SLOW MOVING SYSTEM.
SEVERE THREAT SHOULD BE LITTLE TO NONE...WITH EXCEPTION OF PERHAPS
THAT FAR SOUTHERN TIER AROUND KSUX...AS EVEN MORE ELEVATED STORMS
COULD PRODUCE A HAIL THREAT GIVEN THE POTENTIAL STEEPER LAPSE RATES
ADVECTING AHEAD OF UPPER LOW FROM LATER TUESDAY NIGHT THROUGH
WEDNESDAY EVENING. MORE CERTAIN WILL BE SOME APPRECIABLE RAINFALL
POTENTIAL MIDWEEK...AN INCH OR TWO IN MANY LOCATIONS.
SYSTEM PULLS EAST THURSDAY WITH LINGERING AREAS OF LIGHT RAIN... AND
WILL REPLAY THE MORE WIDESPREAD LOWER CLOUDS. SHEARING OUT THE
SYSTEM SHOULD END THE PRECIP THREAT OVER MOST OF THE AREA THURSDAY
NIGHT...PERHAPS A FEW SPITS EARLY ON IN SW MN.
FRIDAY PERHAPS THE MOST PLEASANT DAY OF THE UPCOMING WEEK IN TERMS
OF DRY WEATHER...JUST A BIT ON THE COOL SIDE OF NORMAL...AND AGAIN
STRUGGLING WITH LINGERING CLOUDS...AND INCREASE AHEAD OF YET ANOTHER
WEATHER SYSTEM FOR THE WEEKEND. WILL REPLAY THE INCREASE IN WARM
ADVECTION AND OVERSPREADING OF LIFT FORCING FRIDAY NIGHT INTO
SATURDAY...ALONG WITH INCREASING ELEVATED INSTABILITY FOR SOME
THUNDER ONCE AGAIN. TEMPS REMAINING ON THE COOL SIDE OF NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 631 PM CDT SAT APR 23 2016
SOUTHERLY WINDS WILL BE QUITE GUSTY UNTIL SUNSET...FREQUENTLY
GUSTING TO 25 TO 30 KNOTS BEFORE SUBSIDING RELATIVELY SPEAKING
AFTER SUNSET. IT IS ANTICIPATED THAT VFR CONDITIONS WILL PREVAIL
THROUGH SUNDAY. HOWEVER THE NAM IS POINTING AT SOME POSSIBLE MVFR
CEILINGS SUNDAY MORNING. LEFT IT OUT OF THE TAFS FOR NOW AS THIS
SCENARIO WAS NOT BACKED UP BY OTHER MODELS SUCH AS THE RAP AND
GFS. BUT DID HEDGE AS A HEADS UP AND KEPT A SCATTERED DECK GOING.
FOR SUNDAY AFTERNOON...LEFT THE MENTION OF TSRA OUT OF THE KFSD
AND KSUX TAF SITES FOR NOW AS MUCH OF THE ACTIVITY MAY DEVELOP
WEST OF INTERSTATE 29.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...JH
LONG TERM...CHAPMAN
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
412 AM CDT FRI APR 22 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM CDT FRI APR 22 2016
THE REAL CHALLENGE TODAY WILL BE THE EXPANDING STRATUS FIELD ACROSS
PARTS OF NORTHWEST IOWA AND SOUTHWEST MINNESOTA. WHILE IT HAS THUS
FAR REMAIN JUST EAST OF FSD AND SUX...STILL A DECENT CHANCE THAT IT
COULD EXPAND FURTHER TO THE WEST...ESPECIALLY AROUND SUX. EXPECT THE
STRATUS TO LINGER THROUGH MID TO LATE MORNING IN PARTS OF NORTHWEST
IOWA AND SOUTHWEST MINNESOTA...BEFORE GIVING WAY TO A SUNNY
DAY.STARTING TO GET A LITTLE WORRIED HOWEVER WITH A LOW LEVEL WIND
FIELD TURNING TO THE NORTHEAST AND EAST THROUGH THE DAY THAT THIS
STRATUS WILL BE DIFFICULT TO SHAKE. WINDS WILL BE LIGHT ACROSS THE
AREA AND WITH PLENTY OF SUNSHINE HIGHS IN THE 60S WILL FEEL PRETTY
NICE.
BY TONIGHT THE RIDGE OF HIGH PRESSURE WILL MOVE EAST OF THE AREA
ALLOWING A SOUTH TO SOUTHEAST WIND TO DEVELOP. LOWS WILL BE MILDEST
IN CENTRAL SOUTH DAKOTA WHERE WINDS WILL INCREASE QUICKEST WHILE THE
COOLER READINGS WILL BE IN THE LOW SPOTS ACROSS NORTHWEST IOWA WHERE
WINDS WILL LIKELY REMAIN AT ABOUT 6 OR 7 MPH OR LESS THROUGH MOST OF
THE NIGHT. EXPECT LOWS TO RANGE FROM THE LOWER 50S IN CENTRAL SOUTH
DAKOTA TO THE MID 40S IN NORTHWEST IOWA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 412 AM CDT FRI APR 22 2016
SOUTHERLY FLOW INCREASES ON SATURDAY AS AN INTENSIFYING AREA OF LOW
PRESSURE APPROACHES FROM THE WEST. WITH THE GULF OPENING UP...THERE
IS SOME QUESTION AS TO HOW QUICKLY MOISTURE RETURNS ACROSS THE
AREA.MODELS SUGGEST 20-30 KNOTS OF SOUTHERLY FLOW THROUGH A DEEP
PORTION OF THE ATMOSPHERE...AND WITH A LITTLE EASTERLY COMPONENT
SHOULD KEEP SPEEDS BELOW ADVISORY LEVEL. THE NAM IS THE MOST
AGGRESSIVE WITH THE MOISTURE...AND ACTUALLY BECOMES UNSTABLE WITH
SATURATION AROUND 800 MB BY SUNDAY MORNING. THE OPERATIONAL RUN OF
THE NAM IS CLOSE TO 2000 J/KG OF CAPE...WHILE OTHER MEMBERS OF THE
SREF ARE MUCH MORE STABLE. WITH THE OPERATIONAL RUN OF THE NAM
BEING AN OUTLIER AND THE GFS REMAINING STABLE...IS A TOUGH CALL AND
LEFT LOW POPS IN. BEST CHANCES FOR STORMS ON SUNDAY APPEAR TO BE IN
THE EAST AHEAD OF THE TROUGH.
AS THE TROUGH MOVES THROUGH...MUCH COOLER MORE STABLE AIR IS
EXPECTED TO MOVE IN. MODEL SOUNDINGS SUGGEST STRATUS
POTENTIAL...AND MAY SQUEEZE OUT SOME DRIZZLE. DROPPED MENTION OF
POPS AT THIS POINT ACROSS THE SOUTH...AND MAY NEED TO DO THE SAME
THING IN THE NORTH AS ATMOSPHERE APPEARS TO BE QUITE STABLE. FOR
NOW...DROPPED POPS JUST TO A SLIGHT CHANCE.
DROPPED MENTION OF POPS ON MONDAY NIGHT AS FORECAST AREA IS IN
BETWEEN SYSTEMS. NEXT SYSTEM MOVES INTO THE CENTRAL PORTIONS OF THE
PLAINS. TOUGH CALL ON HIGHS ON TUESDAY...AS WE WILL LIKELY BE
SHROUDED IN CLOUDS WITH INCREASING EASTERLY FLOW. REAL QUESTION AS
TO HOW FAR NORTH THE WARM FRONT WILL WORK THROUGHOUT THE DAY. FOR
NOW...DECREASED HIGHS A FEW DEGREES ACROSS THE NORTH WHERE THE WARM
FRONT IS UNLIKELY TO REACH.
THEREAFTER...DIFFICULT FORECAST AS MODELS ARE UNSURE HOW MUCH COLD
AIR WILL COME DOWN. JUST THE GFS AND ECMWF ARE OFF NEARLY 10C AT 925
HPA. FOR NOW...STUCK FAIRLY CLOSE TO CONSENSUS...WHICH IS NEARLY
ISOTHERMAL IN THE EC WORLD.
SURFACE RIDGE IS EXPECTED TO BUILD INTO THE REGION LATE WEEK... BUT
APPEARS AS THOUGH CLOUDS WILL ACCOMPANY THE RIDGE...MAKING
TEMPERATURES TRICKY. FOR NOW...STUCK CLOSE TO CONSENSUS BUT COULD
BE STUBBORN TO WARM.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1041 PM CDT THU APR 21 2016
06Z TAFS ARE LIKELY GOING TO REFLECT VFR CONDITIONS WITH A COUPLE
OF CAVEATS. FIRST...STILL A LITTLE CONCERNED ABOUT PATCHY FOG
DEVELOPMENT IN THE JAMES RIVER VALLEY LATE TONIGHT AND EARLY
FRIDAY...RIGHT ALONG A SURFACE RIDGE AXIS WHICH WILL GIVE VERY
LIGHT WINDS IN THAT AREA. THEREFORE HEDGED WITH SOME MVFR TYPE FOG
FOR KHON...BUT AT THIS TIME DO NOT HAVE ENOUGH CONFIDENCE TO GO
ANY WORSE THEN THAT SINCE THE FOG MAY NOT FORM AT ALL. SECOND...
THERE ARE SOME INDICATIONS FROM THE LATEST NAM AND HRRR FIELDS
THAT THERE WILL BE ABUNDANT HUMIDITY IN THE VERY LOW LEVELS JUST
ABOVE THE SURFACE LATE TONIGHT THROUGH MID FRIDAY MORNING AT KSUX.
THE GROUND IS QUITE WET IN THAT AREA...SO IT MAY BE AN ARTIFACT OF
GROUND MOISTURE. BUT FOR A HEADS UP...DECIDED TO INCLUDE A
SCATTERED DECK AT 800 FEET JUST IN CASE SOME LOWER STRATUS FORMS
JUST BEFORE SUNRISE AND LINGERS INTO MID MORNING AT KSUX.
OTHERWISE CURRENTLY...UPPER END IFR TO MVFR STRATUS IS MOVING
SOUTHWARD ACROSS PARTS OF SOUTHWEST MN AND NORTHWEST IA. AT THIS
TIME...THE TRAJECTORY OF THESE CLOUDS SUGGEST THAT THEY WILL STAY
TOO FAR EAST TO IMPACT KSUX OR KFSD...BUT ESPECIALLY AT KSUX...IT
WILL BE CLOSE FOR A FEW HOURS.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...08
LONG TERM...BT
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1010 PM CDT SAT APR 23 2016
.UPDATE...
CONVECTION CONTINUES TO DEVELOP ALONG THE LOWER RIO GRANDE THIS
EVENING ASSOCIATED WITH A COMPACT SHORTWAVE PUSHING EAST INTO THE
STATE. EXPECT HIGH CLOUDS ASSOCIATED WITH THIS ACTIVITY TO
OVERSPREAD THE REGION FROM THE WEST/SOUTHWEST TONIGHT. THINK MOST
OF THE REGION WILL STAY DRY TONIGHT... BUT ADDED CHANCE/30 POPS
OVER THE SOUTHWESTERN COUNTIES/MATAGORDA BAY AREA SUNDAY MORNING
WITH THE APPROACH OF THE SHORTWAVE AND LOW LEVEL MOISTURE RETURN
OCCURRING MUCH QUICKER THAN WHAT PRELIMINARY 00Z GUIDANCE AND THE
LATEST RAP ARE SUGGESTING. THE KHGX VAD WIND PROFILE ALREADY SHOWS
SOUTHERLY FLOW 15-20 KNOTS THROUGH 5KFT... WITH THE GUIDANCE
INSISTING ON A MORE BACKED/DRIER FLOW PERSISTING UNTIL AFTER 06Z.
OTHERWISE... EXPECT OVERNIGHT LOWS TO FALL INTO THE UPPER 50S TO
MID 60S.
HUFFMAN
&&
.PREV DISCUSSION... /ISSUED 611 PM CDT SAT APR 23 2016/
AVIATION...
VFR CONDS EXPECTED THROUGH ABOUT 09Z. MIGHT GET SOME SHALLOW
GROUND FOG ONCE AGAIN BUT CIRRUS STREAMING INTO THE AREA WILL
LIMIT COVERAGE AND INTENSITY. A STRONG S/WV OVER NORTHERN MEXICO
WILL APPROACH ON SUNDAY. FCST SOUNDINGS DON`T LOOK TOO IMPRESSIVE
BUT THE S/WV LOOKS GOOD ON WATER VAPOR AND UPPER LEVEL WINDS ARE
BROADLY DIVERGENT SO SHRA/ISO TSRA SEEMS REASONABLE. KEPT THUNDER
OUT OF THE TAFS FOR NOW AND WILL RE-EVALUATE TSRA POTENTIAL FOR
03Z UPDATE. 43
PREV DISCUSSION... /ISSUED 318 PM CDT SAT APR 23 2016/
DISCUSSION...
GIVEN THE WAY THIS WEEK STARTED...GREAT TO END THE WEEK WITH SOME
BEAUTIFUL WEATHER ACROSS SE TEXAS. TEMPERATURES HAVE REACHED THE
LOW 80S WITH LOW HUMIDITY THIS AFTERNOON. ONE CANNOT ASK FOR MUCH
BETTER WEATHER TO BE OUTSIDE.
SUNDAY AN UPPER LEVEL TROUGH SHOULD MOVE OVER THE REGION DURING
THE AFTERNOON AND EVENING. WATER VAPOR SATELLITE IMAGERY SHOWS
THIS SYSTEM OVER MEXICO. THE FORECAST WILL KEEP SOME HIGHER RAIN
CHANCES OFF TO THE SOUTHWEST OF HOUSTON BUT LOOKS LIKE THOSE
CHANCES DIMINISH TOWARDS THE EVENING HOURS. OUTSIDE OF THE
CANADIAN MODEL...MOST MODELS INCLUDING HIGH RESOLUTION CONVECTIVE
ALLOWING MODELS DO NOT PRODUCE MUCH CONVECTION. GFS SEEMS TO BE ON
THE HIGH END FOR QPF BUT EVEN IT ENDS PRECIPITATION IN THE
EVENING. REGARDLESS CLOUD COVER SHOULD INCREASE ACROSS THE AREA
AND HOLD TEMPERATURES IN THE LOW 80S AS MOISTURE RETURNS.
WATER VAPOR IMAGERY SHOWS ANOTHER STRONG UPPER LOW AND JET STREAM
OUT OVER THE PACIFIC AND GULF OF ALASKA. THIS SYSTEM SHOULD PULL
INTO THE ROCKIES TUESDAY MORNING AND INTO THE PLAINS BY 00Z
WEDNESDAY. THIS SYSTEM WILL PROVIDE A FAVORABLE SET UP FOR SEVERE
WEATHER ACROSS THE PLAINS. ACROSS SOUTHEAST TEXAS...FAIRLY STRONG
CAP IS EXPECTED TO DEVELOP WHICH SHOULD RESTRICT CONVECTIVE
DEVELOPMENT. THERE STILL MAY BE SOME PASSING SHOWERS DUE TO
MOISTURE/WARM AIR ADVECTION PATTERN. A TRAILING PACIFIC FRONT OR
DRY LINE MAY PUSH INTO THE AREA AND STALL ON WEDNESDAY SO
MAINTAINED 30/40 POPS FOR THE REGION. THE GFS AND ECMWF HAVE SOME
DIFFERENCES IN THIS EVOLUTION WITH THE ECMWF MORE AGGRESSIVE WITH
PRECIP CHANCES. THAT SAID...GFS MODEL SOUNDINGS SHOW THE CAP
WEAKENING ON WEDNESDAY.
IN THE EXTENDED FORECAST...WE WILL NEED TO KEEP AN EYE ON THE NEXT
SYSTEM AFTER THE MIDWEEK SYSTEM. BOTH GFS/ECMWF DEPICT A DEEP
TROUGH OVER THE SOUTHERN ROCKIES. ECMWF IS MORE CONCERNING SINCE
IT HAS A BETTER DIFFLUENT JET STRUCTURE WHICH WOULD ALLOW FOR A
WEAKER CAP AND WIDESPREAD CONVECTION. THIS IS A MODEL SIGNAL THAT
MAY NEED TO BE MONITORED IN THE MODEL RUNS FOR THE NEXT FEW DAYS.
THE ECMWF SOLUTION WILL LARGELY DEPEND ON HOW DEEP THE TROUGH
DEVELOPS OVER THE SOUTHERN ROCKIES INTO MEXICO.
OVERPECK
MARINE...
LIGHT OFFSHORE WINDS WILL PREVAIL OVER THE COASTAL WATERS TONIGHT.
OVER THE BAYS THE BRIEF ONSHORE FLOW IN THE WAKE OF THE SEABREEZE
SHOULD GIVE WAY TO A LIGHT ELY FLOW OVERNIGHT. WITH THE SFC HIGH
MOVING FURTHER EAST OF THE REGION TOMORROW...ONSHORE WINDS ARE EX-
PECTED TO RETURN ACROSS THE AREA TOMORROW...STRENGTHENING THROUGH
MUCH OF THE UPCOMING WEEK IN RESPONSE TO A SERIES OF DISTURBANCES
MOVING IN FROM THE SW. WE COULD SEE CAUTION FLAGS OVER THE MARINE
WATERS STARTING MON NIGHT ON INTO THURS. 41
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 60 81 67 84 69 / 10 20 20 10 10
HOUSTON (IAH) 61 81 67 83 70 / 10 20 20 10 10
GALVESTON (GLS) 68 77 71 79 73 / 10 30 20 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...14
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
627 PM CDT SAT APR 23 2016
.AVIATION...
AN UPPER LEVEL SHORT WAVE TROUGH WILL EJECT FROM THE COLORADO
ROCKIES ONTO THE CENTRAL HIGH PLAINS SUNDAY MORNING. SFC PRESSURE
GRADIENT WILL REMAIN TIGHT...KEEPING SOUTH WINDS BREEZY OVERNIGHT
THEN VEERING TO SOUTHWEST SUNDAY MORNING. LOW LEVEL MOISTURE
RETURN OVERNIGHT...BUT ANY STRATUS SHOULD STAY TO THE SOUTH.
&&
.PREV DISCUSSION... /ISSUED 349 PM CDT SAT APR 23 2016/
SHORT TERM...
THE DRYLINE HAS BEEN SITTING IN EASTERN NM FOR SOME TIME TODAY AND
SHOULD STAY THERE...FOR THE MOST PART... UNTIL THE UPPER LEVEL LOW
PUSHES CLOSER TO THE REGION. CONVECTION ALONG THE DRYLINE STILL
LOOKS UNLIKELY AS LIFT LOOKS TO BE HARD TO COME BY. THE BEST CHANCE
FOR LIFT WOULD BE WITH THE DRYLINE. THE BEST SURFACE CONVERGENCE
ALONG THE DRYLINE IS NORTH IN THE TEXAS PANHANDLE. A LOCALIZED AREA
OF ENHANCE CONVERGENCE HAS RECENTLY SET UP OVER THE TX/NM STATE LINE
AROUND PARMER COUNTY. THIS HAS RESULTED IN A SHALLOW CU FIELD.
ENOUGH LIFT FOR ISOLATED SHOWER DEVELOPMENT IS NOT OUT OF THE
QUESTION...HOWEVER THUNDERSTORM DEVELOPMENT IS NOT HIGH ON THE
EXPECTATION LIST. THIS IS DUE TO CONVECTION HAVING TO OVERCOME A
SUBSIDENCE INVERSION IN THE UPPER-MID LEVELS AS WELL AS THERE BEING
A LACK OF CAPE. THE HRRR SEEMS TO BE THE MOST GENEROUS OF THE MODELS
IN HANDING OUT CAPE WHICH IS ONLY A COUPLE HUNDRED J/KG AT BEST
ACROSS OUR NORTHWESTERN ZONES. FOR NOW THE FORECAST WILL REFLECT A
MENTION OF ISOLATED SHOWERS BEFORE 1 AM AND NO MENTION OF THUNDER.
WINDS WILL STAY GUSTY INTO THE NIGHT AHEAD OF AND BEHIND THE
DRYLINE. WINDS WILL BE MOSTLY OUT OF THE WEST BY EARLY TOMORROW
AFTERNOON ACROSS THE CAPROCK AND WILL INCREASE TO THE 25 MPH RANGE
AS THE MAIN ENERGY FROM THE UPPER LOW PASSES TO OUR NORTH. ALDRICH
LONG TERM...
WARM...DRY AND BREEZY CONDITIONS ARE IN STORE THROUGH TUESDAY.
THE SECOND IN A SERIES OF UPPER LOWS/TROUGHS WILL SWING ACROSS THE
SOUTHERN HIGH PLAINS TUESDAY AFTERNOON...PRODUCING THE WINDIEST
DAY OF THE PERIOD. GFS MOS GUIDANCE CONTINUES TO HOVER AROUND 30
TO 34 KTS AT LUBBOCK...WHILE THE MET IS AROUND 20 KTS. WE
CONTINUE TO PLY THE MIDDLE-GROUND AT AROUND 25 KTS OR SO...OR 25
TO 30 MPH WITH GUSTS TO AROUND 40 MPH. HIGH TEMPS MONDAY AND
TUESDAY SHOULD BE IN THE 80S TO LOW 90S. WE HAVE RETAINED A SLIVER
OF T-STORM CHANCES IN THE SRN ROLLING PLAINS LATE THURSDAY...BUT
THE LATEST INDICATIONS ARE THAT THE DRYLINE WILL BE TO THE EAST OF
THE AREA...BUT IT IS NOT OUT OF THE QUESTION SOME STORMS COULD
DEVELOP IN THAT AREA AS THE DRYLINE RETREATS SOMEWHAT IN THE
EVENING. WEDNESDAY SHOULD BE SLIGHTLY COOLER AS FLOW SWITCHES TO
NORTHWEST...THEN A COLD FRONT WILL MOVE THROUGH WEDNESDAY NIGHT OR
EARLY THURSDAY. THE NEXT UPPER LOW IS STILL FORECAST TO DIG INTO
THE DESERT SOUTHEAST MIDWEEK WITH NOT MUCH CHANGE IN TRACK THE
PAST 24 HRS. SURFACE RIDGING...A STRENGTHENING SRLY LOW-LEVEL JET
AND SW FLOW ALOFT THURSDAY SHOULD RETURN GULF MOISTURE INTO THE
AREA AND ALONG WITH SOME ISENTROPIC UPGLIDE...BEGIN TO INCREASE
PRECIP CHANCES. DURING THE DAY THURSDAY THESE CHANCES MAY BE
CONFINED TO OUR SRN AND ERN COUNTIES WHERE THE DEEPER MOISTURE IS
EXPECTED TO BE NOSING IN FROM THE SOUTH. THURSDAY NIGHT INTO
FRIDAY MORNING WE COULD SEE SHOWER AND T-STORM ACTIVITY INCREASE
AS LARGE-SCALE ASCENT FROM THE UPPER LOW BEGINS TO SPREAD OVER THE
REGION. BY FRIDAY...THE MED- RANGE SOLUTIONS BEGIN TO DIVERGE WITH
THE SURFACE DETAILS AS THE GFS BRINGS A DRYLINE INTO THE AREA
WHILE THE ECMWF MAINTAINS SURFACE RIDGING. OVERALL...THE PATTERN
CERTAINLY APPEARS FAVORABLE FOR T-STORM ACTIVITY...AND POSSIBLY
SEVERE WEATHER...BUT AS USUAL THE CONFIDENCE IN THE DETAILS IS LOW
THIS FAR OUT. THE UPPER- TROUGH IS CURRENTLY EXPECTED TO PASS
ACROSS WEST TEXAS DURING THE DAY SATURDAY...DRAGGING PRECIP.
CHANCES EASTWARD WITH IT.
FIRE WEATHER...
THE FIRE DANGER WILL BECOME ELEVATED ACROSS MUCH OF THE CAPROCK
EACH AFTERNOON SUNDAY THROUGH TUESDAY. CONDITIONS WILL LIKELY BE
THE WORST ON TUESDAY AS A PASSING STORM SYSTEM BRINGS STRONGER
WIND SPEEDS. HOWEVER...THE OVERALL FIRE DANGER WILL BE REDUCED BY
THE SEASONAL GREEN-UP ACROSS THE AREA.
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
111 AM CDT FRI APR 22 2016
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...SOME LOCALIZED FOG NOW IN CAMERON COUNTY...ESPECIALLY
AT HRL. LOOKS LIKE MVFR CEILINGS WILL DEVELOP AND PERSIST THROUGH
MID TO LATE THIS MORNING. HIGH PRESSURE ASSOCIATED WITH A WEAK
FRONT WILL PUSH INTO THE AREA TODAY WITH LIGHT WINDS BACKING TO
EAST AND NORTHEAST. COULD SEE A FEW SHOWERS AROUND THE AREA THIS
MORNING...BUT DRIER AIR WILL BE MOVING IN LATER IN THE DAY...WITH
DIMINISHED RAIN CHANCES TONIGHT...FRIDAY NIGHT.
&&
.PREV DISCUSSION... /ISSUED 337 PM CDT THU APR 21 2016/
SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...LATEST SATELLITE IMAGERY
SHOWS AN OUTFLOW BOUNDARY EXTENDING FROM NORTH OF LAREDO TO NEAR
KINGSVILLE THIS AFTERNOON. THE COMBINATION OF A SOUTHWARD MOVING
BOUNDARY ACROSS SOUTH TEXAS...AN INLAND MOVING SEA BREEZE EXTENDING
FROM BROWNSVILLE TO NEAR CORPUS CHRISTI AND DAYTIME HEATING WILL
SUPPORT THE DEVELOPMENT OF ISOLATED TO SCATTERED CONVECTION FOR THE
REST OF THE AFTERNOON INTO THIS EVENING. BROWNSVILLE RADAR CURRENTLY
SHOWS ISOLATED ACTIVITY ACROSS KENEDY AND WILLACY COUNTIES. THE
STORM PREDICTION CENTER /SPC/ HAS ALL OF DEEP SOUTH TEXAS UNDER A
MARGINAL RISK OF SEVERE WEATHER THROUGH TONIGHT. THE MAIN THREATS
FROM ANY OF THE STORMS THAT DEVELOP THIS AFTERNOON INTO THIS EVENING
WILL BE SMALL HAIL...GUSTY WINDS AND LOCALLY HEAVY RAINFALL.
THE 21Z HRRR INDICATES CONVECTION WILL CONTINUE TO DEVELOP ACROSS
THE COASTAL COUNTIES THROUGH LATE AFTERNOON WITH ADDITIONAL
DEVELOPMENT ACROSS ZAPATA AND STARR THIS EVENING. THE 12Z NAM KEEPS
MOST OF THE CONVECTION OVER THE GULF WATERS...THE 12Z GFS SHOWS A
LITTLE CONVECTION OVER THE VALLEY...AND THE 12Z ECMWF SHOWS MORE
ROBUST CONVECTION ACROSS THE AREA. BASED ON CURRENT TRENDS WILL GO
ABOVE MET/MAV GUIDANCE FOR POPS THROUGH THE REST OF THIS AFTERNOON
AND EVENING.
THE APPROACH AND PASSAGE OF A 500 MB DISTURBANCE ALONG WITH A WEAK
COLD FRONT SAGGING SOUTH WILL GENERATE ISOLATED SCATTERED CONVECTION
OVER PORTIONS OF DEEP SOUTH TEXAS TONIGHT. THE COLD FRONT STALLS
OVER DEEP SOUTH TEXAS FRIDAY AND FRIDAY NIGHT. POOLING MOISTURE IN
ADVANCE OF THIS SURFACE FEATURE WILL COMBINE WITH DAYTIME
HEATING...AND ENHANCED SEA BREEZE EFFECT...AND ANOTHER WEAK 500 MB
DISTURBANCE TO PRODUCE MAINLY SCATTERED CONVECTION ON FRIDAY. LOW
TEMPERATURES TONIGHT WILL GENERALLY BE IN THE LOWER 70S. HIGH
TEMPERATURES FRIDAY WILL RANGE FROM THE LOWER 80S NEAR THE COAST TO
THE UPPER ACROSS THE UPPER VALLEY. LOW TEMPERATURES WILL BE SLIGHTLY
COOLER FRIDAY NIGHT WITH TEMPERATURES FALLING INTO THE MID 60S TO
AROUND 70.
MARINE...NOW THROUGH FRIDAY NIGHT...BUOY 42020 REPORTED NORTH WINDS
AROUND 2 KNOTS GUSTING TO AROUND 4 KNOTS WITH SEAS SLIGHTLY UNDER
3.3 FEET WITH A PERIOD OF 7 SECONDS AT 15 CDT/19 UTC. A WEAK
GRADIENT ALONG THE LOWER TEXAS COAST WILL MAINTAIN LIGHT TO MODERATE
WINDS AND LOW TO MODERATE SEAS THROUGH THE PERIOD. NO SMALL CRAFT
EXERCISE CAUTION OR SMALL CRAFT ADVISORY ANTICIPATED.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
54/66
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
202 PM EDT FRI APR 22 2016
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL APPROACH THE REGION FROM THE WEST
TODAY BEFORE PASSING THROUGH THE AREA OVERNIGHT INTO EARLY
SATURDAY. HIGH PRESSURE SHOULD BUILD IN BEHIND THIS SYSTEM LATER
SATURDAY AND REMAIN OVER THE REGION THROUGH MONDAY. THE NEXT COLD
FRONT WILL SLIDE SOUTH THROUGH THE AREA ON TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 240 AM EDT FRIDAY...
WEAKENING UPPER LOW AND ITS ASSOCIATED SURFACE COLD FRONT WILL FINALLY
PUSH EAST TODAY REACHING THE BLUE RIDGE THIS EVENING BEFORE THE FRONT
SLIDES TOWARD THE COAST TOWARD DAYBREAK SATURDAY. QUICK INCREASE IN
DEEPER MOISTURE PER SPIKE IN PWATS TO JUST BELOW 1.5 INCHES SHOULD
BRING A BIT MORE IN THE WAY OF MUCH NEEDED RAINFALL INTO THIS
EVENING. HOWEVER JUST HOW THINGS UNFOLD AND THE DEGREE OF DEEPER
CONVECTION REMAINS UNCERTAIN...ESPCLY GIVEN POTENTIAL FOR MULTIPLE
BANDS AHEAD OF THE FRONT DESPITE LACK OF DEEP INSTABILITY PER
LIMITED HEATING. LATEST MODELS DEPICT THIS WELL WITH AN INITIAL
BAND OF SHOWERS REDEVELOPING OVER THE WEST THIS MORNING ALONG AN
AXIS OF DIFFLUENCE AND DRIVEN BY WEAK SHORTWAVE ENERGY JUST AHEAD
OF THE ACTUAL FRONT. HRRR HAS THIS AXIS OF SHOWERS ALL THE WAY OUT
TO THE BLUE RIDGE THIS MORNING WHICH LOOKS OVERDONE...ALTHOUGH
OTHER SOLUTIONS VARY ON TIMING BUT TEND TO SUPPORT THIS SCENARIO.
THEREFORE TRENDED HIGHER POPS IN THAT DIRECTION EARLY ON.
ONCE THIS BAND SPREADS EAST...GUIDANCE SHOWS SOME INCREASE IN
INSTABILITY PIEDMONT ALONG ITS LEADING EDGE...AND THEN OUT WEST
AHEAD OF ANOTHER BAND OR TWO JUST AHEAD OF THE FRONT. HOWEVER
FORECAST CAPES/BULK SHEAR NOT IMPRESSIVE ESPCLY WITH INSOLATION
TEMPERED BY CLOUDS/SHRA UNLESS MODELS ARE OVERDONE AND MORE
HEATING IS REALIZED. FOR NOW WILL TREND TOWARD WESTERN SHOWER
COVERAGE EARLY...THEN HAVE MORE WIDESPREAD SHOWERS PER LIKELY OR
BETTER POPS THIS AFTERNOON ALL SECTIONS...INCLUDING MORE THUNDER
MENTION FAR WEST AND ESPCLY SOUTHEAST WHERE SHOULD GET A LITTLE
MORE HEATING. OTRW KEEPING MAINLY ISOLATED THUNDER MENTION
ELSEWHERE WHICH MAY BE GENEROUS. TRIMMED HIGH TEMPS BACK A CAT OR
SO ESPCLY WEST WHERE COULD GET STUCK IN THE LOW/MID 60S WITH ONLY
THE EAST PERHAPS 67-72 OR WARMER.
CORRIDOR OF BETTER LIFT SHOULD SPILL EAST OF THE AREA AHEAD OF THE
FRONT THIS EVENING WITH THE OPENING 5H LOW LIKELY KEEPING SOME SHOWERS
AND ISOLATED TSRA GOING MAINLY NORTH/NW ESPCLY BEFORE MIDNIGHT. OTRW
FLOW TURNING NW BEHIND THE BOUNDARY LOOKS TO CUT INTO LINGERING
SHRA ELSEWHERE...SO STEADILY REDUCING POPS AFTER 00Z WITH ONLY
20/30 POPS REMAINING FOR THE MOST PART AFTER MIDNIGHT. TOTAL QPF
LOOKS TO BE A BIT MORE PENDING COVERAGE WITHIN BANDS PERHAPS
RESULTING IN .30 TO .75 WITH THE HIGHEST AMOUNTS OVER THE SOUTH
AND WEST AT THIS POINT. COOL ADVECTION BEHIND THE FRONT RATHER
WEAK OVERNIGHT AND WITH LINGERING CLOUDS EXPECT LOWS TO REMAIN
MOSTLY IN THE UPPER 40S TO MID 50S.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
AS OF 245 AM EDT FRIDAY...
AN UPPER LOW WILL DROP SOUTHEAST ACROSS THE REGION ON SATURDAY WITH
ISOLATED TO SCATTERED SHOWERS. HIGH TEMPERATURES ON SATURDAY WILL
RANGE FROM THE UPPER 50S IN THE MOUNTAINS TO THE MID 70S IN THE
PIEDMONT.
THE UPPER TROUGH WILL PUSH OUT INTO THE ATLANTIC OCEAN SATURDAY
EVENING. THIS WILL ALLOW HIGH PRESSURE TO BUILD INTO OUR REGION
SATURDAY NIGHT. LOW TEMPERATURES SATURDAY NIGHT WILL VARY FROM
AROUND 40 IN THE NORTHWEST MOUNTAINS TO THE LOWER 50S IN THE
PIEDMONT.
A 1020 MB SURFACE HIGH PRESSURE WILL BUILD ACROSS OUR AREA SUNDAY.
HIGH TEMPERATURES WILL WARM INTO THE UPPER 60S IN THE WEST TO THE
UPPER 70S IN THE EAST. UNDER MOSTLY CLEAR SKIES...SUNDAY NIGHT LOW
TEMPERATURES WILL DROP INTO THE UPPER 40S TO LOWER 50S. HIGH
PRESSURE WILL REMAINS JUST OF THE NORTH CAROLINA COAST MONDAY INTO
MONDAY NIGHT. IT WILL BE A WARM START TO THE WORKWEEK WITH HIGHS
MONDAY FROM THE MID 70S IN THE MOUNTAINS TO THE LOWER 80S IN THE
PIEDMONT. LOW TEMPERATURES MONDAY NIGHT WILL BE MILD WITH READINGS
GENERALLY IN THE MID 50S TO AROUND 60 DEGREES.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 245 AM EDT FRIDAY...
GUIDANCE OFFERS SOLUTIONS OF A COLD FRONT APPROACHING AND CROSSING
THE AREA TUESDAY INTO WEDNESDAY. HOWEVER...TIMING VARIES BETWEEN THE
GFS AND ECMWF...ALONG WITH THE EXTENT PRECIPITATION WILL REACH AND
PERSIST INTO THE FORECAST REGION.
THE UNCERTAINTY OF THE ABOVE EVENT...TIES INTO THE EVEN GREATER
UNCERTAINTY OF THE NEXT EVENT. THE COLD FRONT IS EXPECTED TO STALL
EITHER OVER...OR SOUTH OF...THE REGION FOR A BRIEF PERIOD OF TIME.
AN APPROACHING UPPER LOW/TROUGH WILL HELP SWING LOW LEVEL WINDS TO
THE SOUTHWEST WEDNESDAY INTO THURSDAY AND LIFT THE STALLED FRONT
BACK NORTH AS A WARM FRONT. AGAIN...WITH EACH SOLUTION OFFERING
DIFFERENCES IN TIMING...PRECIPITATION AMOUNTS AND EXTENT OF THE
PRECIPITATION.
OUR LATEST FORECAST WILL REFLECT A CONSENSUS OF THESE AND OTHER
SOLUTIONS BY WEIGHING HEAVILY ON THE SUPERBLEND SOLUTION. THIS
SCENARIO OFFERS A SLIGHTLY SLOWER ARRIVAL TIME OF THE PRECIPITATION
MONDAY NIGHT INTO TUESDAY...LITTLE CHANGE TO THE PRIOR WEDNESDAY
FORECAST...AND SCATTERED SHOWERS ACROSS THE AREA ON THURSDAY.
INSTABILITY LOOKS STRONG ENOUGH FOR AT LEAST ISOLATED THUNDERSTORMS
TUESDAY...WEDNESDAY...AND THURSDAY AFTERNOON.
TEMPERATURES DURING THIS PORTION OF THE FORECAST WILL TREND MILDER
THROUGH TUESDAY...AND THEN SLIGHTLY COOLER THROUGH THURSDAY.
READINGS WILL BE AROUND TEN DEGREES ABOVE NORMAL FOR THIS TIME OF
YEAR.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 150 PM EDT FRIDAY...
MULTIPLE BANDS OF SHOWERS AND ISOLATED THUNDERSTORMS WILL CROSS
SOUTHWEST VIRGINIA...SOUTHEAST WEST VIRGINIA AND NORTHWEST NORTH
CAROLINA THIS AFTERNOON AND EVENING AHEAD OF A COLD FRONT.
MODERATE TO HEAVY RAIN WILL PRODUCE MVFR VISIBILITIES. CEILINGS
WERE WIDELY VARIABLE...RANGING FROM VFR TO IFR.
NCAR ENSEMBLE AND GEFS FORECAST...AS WELL AS OTHER MODELS WERE
CONSISTENT ON TIMING...WITH A BULK OF THE PRECIPITATION MOVING
EAST OF KDAN AND KLYH AROUND MIDNIGHT. ONCE THE PRECIPITATION
ENDS...HIGH CONFIDENCE OF FOG AND STRATUS OVERNIGHT.
WINDS TURN TO THE NORTHWEST THEN NORTH BEHIND THE COLD FRONT
THAT CROSSES THROUGH THE REGION TONIGHT. THE DOWNSLOPE WIND AND
ARRIVAL OF A DRIER AIRMASS WILL RESULT IN CLEARING ON THE LEE SIDE
OF THE BLUE RIDGE SATURDAY MORNING. MEDIUM TO HIGH CONFIDENCE THAT
KROA WILL ONLY HAVE SCATTERED CLOUDS LEFT BY THE 18Z END OF THE
TAF FORECAST PERIOD. CLOUDS ASSOCIATED WITH THE UPPER LOW MAY
LINGER IN KLYH AND KDAN LONGER ON SATURDAY. CONFIDENCE ON WHEN
CLEARING WILL OCCUR IS NOT AS HIGH FOR THESE SITES. IN THE
MOUNTAINS...LOWER CLOUDS WILL LINGER WELL INTO THE AFTERNOON.
EXTENDED AVIATION DISCUSSION...
WEAK HIGH PRESSURE FOLLOWS SATURDAY NIGHT INTO EARLY NEXT WEEK.
HOWEVER SOME LOWER CIGS MIGHT REDEVELOP ACROSS THE MOUNTAINS BY
SUNDAY AS LIGHT EASTERLY FLOW SETS UP UNDER ANOTHER WEAK WEDGE
WHICH SHOULD FADE BY EARLY NEXT WEEK. THE NEXT WEAK BACKDOOR COLD
FRONT MAY BRING A BAND OF SHOWERS ALONG WITH MOUNTAIN SUB-VFR ON
TUESDAY AND WEDNESDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH
SHORT TERM...KK
LONG TERM...DS/KK
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
652 AM EDT FRI APR 22 2016
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL APPROACH THE REGION FROM THE WEST
TODAY BEFORE PASSING THROUGH THE AREA OVERNIGHT INTO EARLY
SATURDAY. HIGH PRESSURE SHOULD BUILD IN BEHIND THIS SYSTEM LATER
SATURDAY AND REMAIN OVER THE REGION THROUGH MONDAY. THE NEXT COLD
FRONT WILL SLIDE SOUTH THROUGH THE AREA ON TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 240 AM EDT FRIDAY...
WEAKENING UPPER LOW AND ITS ASSOCIATED SURFACE COLD FRONT WILL FINALLY
PUSH EAST TODAY REACHING THE BLUE RIDGE THIS EVENING BEFORE THE FRONT
SLIDES TOWARD THE COAST TOWARD DAYBREAK SATURDAY. QUICK INCREASE IN
DEEPER MOISTURE PER SPIKE IN PWATS TO JUST BELOW 1.5 INCHES SHOULD
BRING A BIT MORE IN THE WAY OF MUCH NEEDED RAINFALL INTO THIS
EVENING. HOWEVER JUST HOW THINGS UNFOLD AND THE DEGREE OF DEEPER
CONVECTION REMAINS UNCERTAIN...ESPCLY GIVEN POTENTIAL FOR MULTIPLE
BANDS AHEAD OF THE FRONT DESPITE LACK OF DEEP INSTABILITY PER
LIMITED HEATING. LATEST MODELS DEPICT THIS WELL WITH AN INITIAL
BAND OF SHOWERS REDEVELOPING OVER THE WEST THIS MORNING ALONG AN
AXIS OF DIFFLUENCE AND DRIVEN BY WEAK SHORTWAVE ENERGY JUST AHEAD
OF THE ACTUAL FRONT. HRRR HAS THIS AXIS OF SHOWERS ALL THE WAY OUT
TO THE BLUE RIDGE THIS MORNING WHICH LOOKS OVERDONE...ALTHOUGH
OTHER SOLUTIONS VARY ON TIMING BUT TEND TO SUPPORT THIS SCENARIO.
THEREFORE TRENDED HIGHER POPS IN THAT DIRECTION EARLY ON.
ONCE THIS BAND SPREADS EAST...GUIDANCE SHOWS SOME INCREASE IN
INSTABILITY PIEDMONT ALONG ITS LEADING EDGE...AND THEN OUT WEST
AHEAD OF ANOTHER BAND OR TWO JUST AHEAD OF THE FRONT. HOWEVER
FORECAST CAPES/BULK SHEAR NOT IMPRESSIVE ESPCLY WITH INSOLATION
TEMPERED BY CLOUDS/SHRA UNLESS MODELS ARE OVERDONE AND MORE
HEATING IS REALIZED. FOR NOW WILL TREND TOWARD WESTERN SHOWER
COVERAGE EARLY...THEN HAVE MORE WIDESPREAD SHOWERS PER LIKELY OR
BETTER POPS THIS AFTERNOON ALL SECTIONS...INCLUDING MORE THUNDER
MENTION FAR WEST AND ESPCLY SOUTHEAST WHERE SHOULD GET A LITTLE
MORE HEATING. OTRW KEEPING MAINLY ISOLATED THUNDER MENTION
ELSEWHERE WHICH MAY BE GENEROUS. TRIMMED HIGH TEMPS BACK A CAT OR
SO ESPCLY WEST WHERE COULD GET STUCK IN THE LOW/MID 60S WITH ONLY
THE EAST PERHAPS 67-72 OR WARMER.
CORRIDOR OF BETTER LIFT SHOULD SPILL EAST OF THE AREA AHEAD OF THE
FRONT THIS EVENING WITH THE OPENING 5H LOW LIKELY KEEPING SOME SHOWERS
AND ISOLATED TSRA GOING MAINLY NORTH/NW ESPCLY BEFORE MIDNIGHT. OTRW
FLOW TURNING NW BEHIND THE BOUNDARY LOOKS TO CUT INTO LINGERING
SHRA ELSEWHERE...SO STEADILY REDUCING POPS AFTER 00Z WITH ONLY
20/30 POPS REMAINING FOR THE MOST PART AFTER MIDNIGHT. TOTAL QPF
LOOKS TO BE A BIT MORE PENDING COVERAGE WITHIN BANDS PERHAPS
RESULTING IN .30 TO .75 WITH THE HIGHEST AMOUNTS OVER THE SOUTH
AND WEST AT THIS POINT. COOL ADVECTION BEHIND THE FRONT RATHER
WEAK OVERNIGHT AND WITH LINGERING CLOUDS EXPECT LOWS TO REMAIN
MOSTLY IN THE UPPER 40S TO MID 50S.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
AS OF 245 AM EDT FRIDAY...
AN UPPER LOW WILL DROP SOUTHEAST ACROSS THE REGION ON SATURDAY WITH
ISOLATED TO SCATTERED SHOWERS. HIGH TEMPERATURES ON SATURDAY WILL
RANGE FROM THE UPPER 50S IN THE MOUNTAINS TO THE MID 70S IN THE
PIEDMONT.
THE UPPER TROUGH WILL PUSH OUT INTO THE ATLANTIC OCEAN SATURDAY
EVENING. THIS WILL ALLOW HIGH PRESSURE TO BUILD INTO OUR REGION
SATURDAY NIGHT. LOW TEMPERATURES SATURDAY NIGHT WILL VARY FROM
AROUND 40 IN THE NORTHWEST MOUNTAINS TO THE LOWER 50S IN THE
PIEDMONT.
A 1020 MB SURFACE HIGH PRESSURE WILL BUILD ACROSS OUR AREA SUNDAY.
HIGH TEMPERATURES WILL WARM INTO THE UPPER 60S IN THE WEST TO THE
UPPER 70S IN THE EAST. UNDER MOSTLY CLEAR SKIES...SUNDAY NIGHT LOW
TEMPERATURES WILL DROP INTO THE UPPER 40S TO LOWER 50S. HIGH
PRESSURE WILL REMAINS JUST OF THE NORTH CAROLINA COAST MONDAY INTO
MONDAY NIGHT. IT WILL BE A WARM START TO THE WORKWEEK WITH HIGHS
MONDAY FROM THE MID 70S IN THE MOUNTAINS TO THE LOWER 80S IN THE
PIEDMONT. LOW TEMPERATURES MONDAY NIGHT WILL BE MILD WITH READINGS
GENERALLY IN THE MID 50S TO AROUND 60 DEGREES.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 245 AM EDT FRIDAY...
GUIDANCE OFFERS SOLUTIONS OF A COLD FRONT APPROACHING AND CROSSING
THE AREA TUESDAY INTO WEDNESDAY. HOWEVER...TIMING VARIES BETWEEN THE
GFS AND ECMWF...ALONG WITH THE EXTENT PRECIPITATION WILL REACH AND
PERSIST INTO THE FORECAST REGION.
THE UNCERTAINTY OF THE ABOVE EVENT...TIES INTO THE EVEN GREATER
UNCERTAINTY OF THE NEXT EVENT. THE COLD FRONT IS EXPECTED TO STALL
EITHER OVER...OR SOUTH OF...THE REGION FOR A BRIEF PERIOD OF TIME.
AN APPROACHING UPPER LOW/TROUGH WILL HELP SWING LOW LEVEL WINDS TO
THE SOUTHWEST WEDNESDAY INTO THURSDAY AND LIFT THE STALLED FRONT
BACK NORTH AS A WARM FRONT. AGAIN...WITH EACH SOLUTION OFFERING
DIFFERENCES IN TIMING...PRECIPITATION AMOUNTS AND EXTENT OF THE
PRECIPITATION.
OUR LATEST FORECAST WILL REFLECT A CONSENSUS OF THESE AND OTHER
SOLUTIONS BY WEIGHING HEAVILY ON THE SUPERBLEND SOLUTION. THIS
SCENARIO OFFERS A SLIGHTLY SLOWER ARRIVAL TIME OF THE PRECIPITATION
MONDAY NIGHT INTO TUESDAY...LITTLE CHANGE TO THE PRIOR WEDNESDAY
FORECAST...AND SCATTERED SHOWERS ACROSS THE AREA ON THURSDAY.
INSTABILITY LOOKS STRONG ENOUGH FOR AT LEAST ISOLATED THUNDERSTORMS
TUESDAY...WEDNESDAY...AND THURSDAY AFTERNOON.
TEMPERATURES DURING THIS PORTION OF THE FORECAST WILL TREND MILDER
THROUGH TUESDAY...AND THEN SLIGHTLY COOLER THROUGH THURSDAY.
READINGS WILL BE AROUND TEN DEGREES ABOVE NORMAL FOR THIS TIME OF
YEAR.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 640 AM EDT FRIDAY...
FLYING CONDITIONS WILL CONTINUE TO DETERIORATE THIS MORNING AS
SHOWERS CONTINUE TO MOISTEN THE COLUMN FROM WEST TO EAST AND IN
TURN ALLOWING CIGS TO FALL INTO MVFR LEVELS OR WORSE THROUGH
MIDDAY. IN ADDITION...PERIODS OF MVFR VSBYS IN RAIN/FOG WILL
OCCUR ACROSS MOST LOCATIONS AT TIMES WITH THE HEAVIER RAINFALL
ALONG THE KBLF/KLWB CORRIDOR AND LESS IN THE EAST.
LOTS OF UNCERTAINTY STILL IN REGARDS TO CIGS AND SHOWER COVERAGE
BY THIS AFTERNOON WITH MODELS WANTING TO MARCH THE EARLY BAND OF
SHOWERS EAST ACROSS KDAN/KLYH MAKING FOR LESS INSTABILITY OVER THE
REGION AHEAD OF THE ACTUAL COLD FRONT LATER IN THE DAY. THIS WOULD
TEND TO LIMIT DEEP CONVECTION TO PERHAPS THE FAR WEST WHERE MAY
SEE MORE BREAKS SOONER WITH MORE EMBEDDED NATURE TSRA ELSEWHERE AT
WORST. SINCE IFFY GIVEN CURRENT MORE WIDESPREAD COVERAGE WITH THE
INITIAL RAINFALL...PLAN TO JUST KEEP IN A VCTS MENTION MOST SPOTS
THIS AFTERNOON WITH PREVAILING MVFR TO OCNL IFR CIGS WITHIN
ADDED SHOWER COVERAGE. IF EARLY RAINFALL FADES OUT SOONER THEN
COULD BREAK INTO A PERIOD OF VFR CIGS BEFORE ADDED CONVECTION
FILLS IN LATER IN THE DAY.
EXPECT THE MAJORITY OF THE SHRA/TSRA TO SHIFT EAST AHEAD OF THE
FRONT THIS EVENING WITH RESIDUAL SHOWERS UNDER THE TRAILING UPPER
LOW THAT WILL CROSS THE REGION OVERNIGHT. THIS FEATURE MAY KEEP
SHOWERS GOING ESPCLY KBLF/KLWB WITH DOWNSLOPE DRYING AND LOSS OF
HEATING LIMITING ADDED COVERAGE OUT EAST WHERE WILL LEAVE OUT
SHRA MENTION AFTER EARLY THIS EVENING. OTRW OVERALL MVFR CIGS
WITH PATCHY MVFR VSBYS IN FOG EAST IN THE WAKE OF THE EARLIER
RAINFALL AND LINGERING LIGHT SHOWERS KLWB VICINITY OVERNIGHT.
EXTENDED AVIATION DISCUSSION...
SOME LINGERING WRAP AROUND MOISTURE ON THE BACK OF THE DEPARTING
UPPER LOW COULD KEEP ADDED SPOTTY SHOWERS AND MVFR CIGS GOING INTO
SATURDAY ESPCLY MOUNTAINS EAST TO KLYH BEFORE IMPROVING LATER IN
THE DAY. WEAK HIGH PRESSURE FOLLOWS SATURDAY NIGHT INTO EARLY NEXT
WEEK. HOWEVER SOME LOWER CIGS MIGHT REDEVELOP ACROSS THE MOUNTAINS
BY SUNDAY AS LIGHT EASTERLY FLOW SETS UP UNDER ANOTHER WEAK WEDGE
WHICH SHOULD FADE BY EARLY NEXT WEEK. THE NEXT WEAK BACKDOOR COLD
FRONT MAY BRING A BAND OF SHOWERS ALONG WITH MOUNTAIN SUB-VFR ON
TUESDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH
SHORT TERM...KK
LONG TERM...DS/KK
AVIATION...AMS/JH/MBS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
324 AM EDT FRI APR 22 2016
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL APPROACH THE REGION FROM THE WEST
TODAY BEFORE PASSING THROUGH THE AREA OVERNIGHT INTO EARLY
SATURDAY. HIGH PRESSURE SHOULD BUILD IN BEHIND THIS SYSTEM LATER
SATURDAY AND REMAIN OVER THE REGION THROUGH MONDAY. THE NEXT COLD
FRONT WILL SLIDE SOUTH THROUGH THE AREA ON TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 240 AM EDT FRIDAY...
WEAKENING UPPER LOW AND ITS ASSOCIATED SURFACE COLD FRONT WILL FINALLY
PUSH EAST TODAY REACHING THE BLUE RIDGE THIS EVENING BEFORE THE FRONT
SLIDES TOWARD THE COAST TOWARD DAYBREAK SATURDAY. QUICK INCREASE IN
DEEPER MOISTURE PER SPIKE IN PWATS TO JUST BELOW 1.5 INCHES SHOULD
BRING A BIT MORE IN THE WAY OF MUCH NEEDED RAINFALL INTO THIS
EVENING. HOWEVER JUST HOW THINGS UNFOLD AND THE DEGREE OF DEEPER
CONVECTION REMAINS UNCERTAIN...ESPCLY GIVEN POTENTIAL FOR MULTIPLE
BANDS AHEAD OF THE FRONT DESPITE LACK OF DEEP INSTABILITY PER
LIMITED PROLONGED HEATING. LATEST MODELS DEPICT THIS WELL WITH AN
INITIAL BAND OF SHOWERS REDEVELOPING OVER THE WEST THIS MORNING
ALONG AN AXIS OF DIFFLUENCE AND DRIVEN BY WEAK SHORTWAVE ENERGY
JUST AHEAD OF THE ACTUAL FRONT. HRRR HAS THIS AXIS OF RATHER LIGHT
SHOWERS ALL THE WAY OUT TO THE BLUE RIDGE THIS MORNING WHICH LOOKS
OVERDONE...ALTHOUGH OTHER SOLUTIONS VARY ON TIMING BUT TEND TO
SUPPORT THIS SCENARIO.
ONCE THIS BAND SPREADS EAST...GUIDANCE SHOWS SOME INCREASE IN
INSTABILITY OUT EAST ALONG ITS LEADING EDGE...AND THEN OUT WEST
AHEAD OF ANOTHER BAND OR TWO JUST AHEAD OF THE FRONT. HOWEVER
FORECAST CAPES/BULK SHEAR NOT IMPRESSIVE ESPCLY WITH INSOLATION
TEMPERED BY CLOUDS/SHRA UNLESS MODELS ARE OVERDONE AND MORE
HEATING IS REALIZED. FOR NOW WILL TREND TOWARD WESTERN SHOWER
COVERAGE EARLY...THEN HAVE MORE WIDESPREAD SHOWERS PER LIKELY OR
BETTER POPS THIS AFTERNOON ALL SECTIONS...INCLUDING MORE THUNDER
MENTION FAR WEST AND ESPCLY SOUTHEAST WHERE SHOULD GET A LITTLE
MORE HEATING. OTRW KEEPING MAINLY ISOLATED THUNDER MENTION
ELSEWHERE WHICH MAY BE GENEROUS. TRIMMED HIGH TEMPS BACK A CAT OR
SO ESPCLY WEST WHERE COULD GET STUCK IN THE 60S WITH ONLY THE EAST
PERHAPS 67-72 OR WARMER.
CORRIDOR OF BETTER LIFT SHOULD SPILL EAST OF THE AREA AHEAD OF THE
FRONT THIS EVENING WITH THE OPENING 5H LOW LIKELY KEEPING SOME SHOWERS
AND ISOLATED TSRA GOING MAINLY NORTH/NW ESPCLY BEFORE MIDNIGHT. OTRW
FLOW TURNING NW BEHIND THE BOUNDARY LOOKS TO CUT INTO LINGERING
SHRA ELSEWHERE...SO STEADILY REDUCING POPS AFTER 00Z WITH ONLY
20/30 POPS REMAINING FOR THE MOST PART AFTER MIDNIGHT. TOTAL QPF
LOOKS TO BE A BIT MORE PENDING COVERAGE WITHIN BANDS PERHAPS
RESULTING IN .30 TO .75 WITH THE HIGHEST AMOUNTS OVER THE SOUTH
AND WEST AT THIS POINT. COOL ADVECTION BEHIND THE FRONT RATHER
WEAK OVERNIGHT AND WITH LINGERING CLOUDS EXPECT LOWS TO REMAIN
MOSTLY IN THE UPPER 40S TO MID 50S.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
AS OF 245 AM EDT FRIDAY...
AN UPPER LOW WILL DROP SOUTHEAST ACROSS THE REGION ON SATURDAY WITH
ISOLATED TO SCATTERED SHOWERS. HIGH TEMPERATURES ON SATURDAY WILL
RANGE FROM THE UPPER 50S IN THE MOUNTAINS TO THE MID 70S IN THE
PIEDMONT.
THE UPPER TROUGH WILL PUSH OUT INTO THE ATLANTIC OCEAN SATURDAY
EVENING. THIS WILL ALLOW HIGH PRESSURE TO BUILD INTO OUR REGION
SATURDAY NIGHT. LOW TEMPERATURES SATURDAY NIGHT WILL VARY FROM
AROUND 40 IN THE NORTHWEST MOUNTAINS TO THE LOWER 50S IN THE
PIEDMONT.
A 1020 MB SURFACE HIGH PRESSURE WILL BUILD ACROSS OUR AREA SUNDAY.
HIGH TEMPERATURES WILL WARM INTO THE UPPER 60S IN THE WEST TO THE
UPPER 70S IN THE EAST. UNDER MOSTLY CLEAR SKIES...SUNDAY NIGHT LOW
TEMPERATURES WILL DROP INTO THE UPPER 40S TO LOWER 50S. HIGH
PRESSURE WILL REMAINS JUST OF THE NORTH CAROLINA COAST MONDAY INTO
MONDAY NIGHT. IT WILL BE A WARM START TO THE WORKWEEK WITH HIGHS
MONDAY FROM THE MID 70S IN THE MOUNTAINS TO THE LOWER 80S IN THE
PIEDMONT. LOW TEMPERATURES MONDAY NIGHT WILL BE MILD WITH READINGS
GENERALLY IN THE MID 50S TO AROUND 60 DEGREES.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 245 AM EDT FRIDAY...
GUIDANCE OFFERS SOLUTIONS OF A COLD FRONT APPROACHING AND CROSSING
THE AREA TUESDAY INTO WEDNESDAY. HOWEVER...TIMING VARIES BETWEEN THE
GFS AND ECMWF...ALONG WITH THE EXTENT PRECIPITATION WILL REACH AND
PERSIST INTO THE FORECAST REGION.
THE UNCERTAINTY OF THE ABOVE EVENT...TIES INTO THE EVEN GREATER
UNCERTAINTY OF THE NEXT EVENT. THE COLD FRONT IS EXPECTED TO STALL
EITHER OVER...OR SOUTH OF...THE REGION FOR A BRIEF PERIOD OF TIME.
AN APPROACHING UPPER LOW/TROUGH WILL HELP SWING LOW LEVEL WINDS TO
THE SOUTHWEST WEDNESDAY INTO THURSDAY AND LIFT THE STALLED FRONT
BACK NORTH AS A WARM FRONT. AGAIN...WITH EACH SOLUTION OFFERING
DIFFERENCES IN TIMING...PRECIPITATION AMOUNTS AND EXTENT OF THE
PRECIPITATION.
OUR LATEST FORECAST WILL REFLECT A CONSENSUS OF THESE AND OTHER
SOLUTIONS BY WEIGHING HEAVILY ON THE SUPERBLEND SOLUTION. THIS
SCENARIO OFFERS A SLIGHTLY SLOWER ARRIVAL TIME OF THE PRECIPITATION
MONDAY NIGHT INTO TUESDAY...LITTLE CHANGE TO THE PRIOR WEDNESDAY
FORECAST...AND SCATTERED SHOWERS ACROSS THE AREA ON THURSDAY.
INSTABILITY LOOKS STRONG ENOUGH FOR AT LEAST ISOLATED THUNDERSTORMS
TUESDAY...WEDNESDAY...AND THURSDAY AFTERNOON.
TEMPERATURES DURING THIS PORTION OF THE FORECAST WILL TREND MILDER
THROUGH TUESDAY...AND THEN SLIGHTLY COOLER THROUGH THURSDAY.
READINGS WILL BE AROUND TEN DEGREES ABOVE NORMAL FOR THIS TIME OF
YEAR.
&&
.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
AS OF 1245 AM EDT FRIDAY...
FLYING CONDITIONS WILL REMAIN VFR A WHILE LONGER OVERNIGHT WITH
CIGS LIKELY QUICKLY DECREASING TO MVFR OR WORSE FROM SW TO NE BY
DAYBREAK AS DEEPER MOISTURE ALONG AN INITIAL FADING BAND OF
SHOWERS WORKS EAST. HOWEVER GIVEN DRYNESS SEEN IN THE EARLIER
EVENING SOUNDINGS...MAY TAKE LONGER TO MOISTEN UP THE COLUMN SO
DELAYED THE ONSET OF THE SUB-VFR CONDITIONS UNTIL JUST BEFORE DAWN
FAR WEST AND BLUE RIDGE INCLUDING POINTS EAST AROUND 12Z/8AM.
COULD ALSO SEE PERIODS OF MVFR VSBYS IN SHOWERS PENDING
REDEVELOPMENT OF THE CURRENT WEAKER BAND OF RAIN OVER THE
MOUNTAINS. LATEST MODEL SUITE CONTINUES TO SUGGEST THAT THIS AREA
OF SHOWERS WILL BECOME MORE WIDESPREAD LATE SO KEEPING LOWER VSBYS
IN SHRA MOST SPOTS BY DAWN.
LOTS OF UNCERTAINTY IN REGARDS TO CIGS AND SHOWER COVERAGE DURING
FRIDAY WITH MODELS WANTING TO MARCH THE EARLY BAND OF SHOWERS EAST
ACROSS KDAN/KLYH MAKING FOR LESS INSTABILITY OVER THE REGION AHEAD
OF THE ACTUAL COLD FRONT LATER IN THE DAY. THIS WOULD TEND TO
LIMIT DEEP CONVECTION TO PERHAPS THE FAR WEST WHERE MAY SEE MORE
BREAKS SOONER WITH MORE EMBEDDED NATURE TSRA ELSEWHERE AT WORST.
SINCE IFFY GIVEN WARMTH AND LIKELY OVERDONE NATURE WITH MODELS
WITH THE INITIAL RAINFALL...PLAN TO KEEP IN AT LEAST A VCTS
MENTION MOST SPOTS THIS AFTERNOON WITH PREVAILING MVFR TO OCNL IFR
CIGS WITHIN LIGHTER SHOWER COVERAGE. IF EARLY RAINFALL IS LESS
THEN COULD BREAK INTO A PERIOD OF VFR CIGS BEFORE ADDED CONVECTION
FILLS IN LATER IN THE DAY.
EXPECT THE MAJORITY OF THE SHRA/TSRA TO SHIFT EAST AHEAD OF THE
FRONT THIS EVENING WITH RESIDUAL SHOWERS UNDER THE TRAILING UPPER
LOW THAT WILL CROSS THE REGION OVERNIGHT. THIS FEATURE MAY KEEP
SHOWERS GOING ESPCLY KBLF/KLWB WITH DOWNSLOPE DRYING AND LOSS OF
HEATING LIMITING ADDED COVERAGE TO THE EAST WHERE WILL LEAVE OUT
ADDED SHRA MENTION AFTER EARLY THIS EVENING. OTRW OVERALL MVFR
CIGS WITH PATCHY MVFR VSBYS IN FOG IN THE WAKE OF THE EARLIER
RAINFALL.
EXTENDED AVIATION DISCUSSION...
SOME LINGERING WRAP AROUND MOISTURE ON THE BACK OF THE DEPARTING
UPPER LOW COULD KEEP ADDED SPOTTY SHOWERS AND MVFR CIGS GOING INTO
SATURDAY ESPCLY MOUNTAINS BEFORE IMPROVING LATER IN THE DAY. WEAK
HIGH PRESSURE FOLLOWS SATURDAY NIGHT INTO EARLY NEXT WEEK. HOWEVER
SOME LOWER CIGS MIGHT REDEVELOP ACROSS THE MOUNTAINS BY SUNDAY AS
LIGHT EASTERLY FLOW SETS UP UNDER ANOTHER WEAK WEDGE WHICH SHOULD
FADE BY EARLY NEXT WEEK. THE NEXT WEAK BACKDOOR COLD FRONT MAY
BRING A BAND OF SHOWERS ALONG WITH MOUNTAIN SUB-VFR ON TUESDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH
SHORT TERM...KK
LONG TERM...DS/KK
AVIATION...AMS/JH/MBS
AREA FORECAST DISCUSSION
NWS SEATTLE WA
900 AM PDT FRI APR 22 2016
.SYNOPSIS...AN UPPER LOW WILL BRING SHOWERS TODAY. AFTER A DRIER
PERIOD EARLY SATURDAY...ANOTHER SYSTEM WILL BRING SHOWERS LATER
SATURDAY AND SUNDAY. A DRYING TREND WILL FOLLOW NEXT WEEK.
&&
.SHORT TERM...SHOWERS OVER NW OREGON AND SW WA WILL SPREAD NORTH
BY AFTERNOON. THE UPPER LOW CENTERED OFF THE NORTH CALIF COAST
WILL MOVE TO SRN IDAHO BY MIDDAY SATURDAY AND SHOWER ACTIVITY
SHOULD DECREASE AS THE LOW DEPARTS. A NEW UPPER TROUGH WILL BRING
AN INCREASING CHANCE OF SHOWERS AGAIN AROUND SATURDAY EVENING.
THAT UPPER TROUGH WILLS SAG INTO THE GREAT BASIN THROUGH MONDAY
WITH SHOWERS DECREASING AGAIN OVER WRN WA AS THAT LOW DEPARTS.
.LONG TERM...A WEAK UPPER RIDGE WILL MOVE OVER THE AREA ON
TUESDAY SO THAT SHOULD BE A DRY DAY. A SPLITTING FRONT WILL FALL
APART JUST OFFSHORE ON WEDNESDAY WITH THE BULK OF THAT PRECIP
HEADING INTO NRN CALIF. MODEL SOLUTIONS DIVERGE ON THURSDAY.
THE GFS HAS ANOTHER UPPER LOW BRUSH THE AREA WITH SOME SHOWERS.
THE ECMWF HAS A RIDGE FOR DRY WEATHER.
&&
.AVIATION...AN UPPER LEVEL LOW OVER THE PAC NW WILL MAINTAIN SHOWERS
ACROSS WESTERN WA TODAY. THE AIR MASS IS MOIST WITH SOUTHERLY FLOW
ALOFT. THE HIGHEST INSTABILITY IS OVER THE CASCADES THIS AFTERNOON
WITH ISOLATED THUNDERSTORMS POSSIBLE. LOW LEVEL ONSHORE FLOW WILL
INCREASE TONIGHT WITH MVFR CIGS LIKELY. 33
KSEA...SHOWERS IN THE VICINITY TODAY. SOUTH FLOW AT THE SURFACE.
CIGS LOWERING TONIGHT WITH MVFR CONDITIONS. 33
&&
.MARINE...WEAK HIGH PRESSURE ALONG THE COAST WILL MAINTAIN ONSHORE
FLOW ACROSS WESTERN WA TODAY. WEST WINDS WILL INCREASE THOUGH THE
STRAIT OF JUAN DE FUCA THIS AFTERNOON - A SMALL CRAFT ADVISORY
REMAINS IN EFFECT. ONSHORE FLOW WILL INCREASE ON SATURDAY AS A COLD
FRONT MOVES INLAND. ONSHORE FLOW WILL CONTINUE THROUGH EARLY NEXT
WEAK WITH HIGH PRESSURE OVER THE NE PAC. THE NEXT FRONT WILL
ARRIVE TUESDAY NIGHT OR WEDNESDAY. 33
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO MIDNIGHT PDT
TONIGHT FOR CENTRAL U.S. WATERS STRAIT OF JUAN DE FUCA-EAST
ENTRANCE U.S. WATERS STRAIT OF JUAN DE FUCA.
&&
$$
WWW.WEATHER.GOV/SEATTLE
YOU CAN SEE AN ILLUSTRATED VERSION OF THIS DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
Area Forecast Discussion
National Weather Service Spokane WA
1104 AM PDT FRI APR 22 2016
.SYNOPSIS...
A strong upper level low and associated cold front will push into
the region today bringing a chance showers with thunderstorms
possible this afternoon and evening. A few of the thunderstorms
will be capable of producing hail and gusty winds. As the low
dives into southern Idaho late tonight, it will shift the focus
for precipitation across southeast Washington and the southern
Idaho Panhandle. This precipitation could be locally heavy at
times with possible mounain snow into Saturday morning. The
threat of showers will then continue through the rest of the
weekend and into early next week, especially for the Idaho
panhandle. Temperatures will be considerably cooler than what
what was experienced over the past several days.
&&
.DISCUSSION...
First band of convection is sliding northward of Spokane across
northeast Washington and across the Panhandle with mainly light
precipitation. Winds veer to the south-southwest behind this band
and expect partial clearing. This will allos the boundary layer to
heat up and instability increase. May see some surface based
convection bubble up by mid afternoon, but it looks to be
isolated. The HRRR shows the best chances across the Cascade
crest, the Blues and across the southern Panhandle. This
convective activity will spread northward into the evening hours
with occasional lightning strikes, brief downpours, gusty winds
and possibly small hail. The arrival of an upper level disturbance
late tonight will bring a more widespread area of showers across
the southeast portion of the forecast area. /rfox.
&&
.AVIATION...
12Z TAFS: Light showers with mid level CIGs will be found north
and east of KGEG through early afternoon. The next round of
convection will be surface based, with the best instability after
21z from KOMK-KGEG-KLWS with a chance of thunderstorms, gusty
winds and possibly small hail. The instability will decrease
after 03z, but a band of light showers will move up from the south
after 08z reaching KLWS and KPUW toward KCOE through the early
morning hours. Little thunderstorm threat expected in KEAT & KMWH,
and winds will veer to the west to northwest by early evening.
/rfox.
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 72 47 61 43 57 40 / 30 50 30 20 60 10
Coeur d`Alene 72 45 58 42 57 39 / 30 70 80 40 50 10
Pullman 70 42 57 41 55 37 / 40 90 90 20 40 20
Lewiston 76 48 60 45 62 42 / 50 90 100 20 40 30
Colville 74 45 68 42 60 39 / 40 60 40 50 60 30
Sandpoint 70 42 58 40 55 36 / 40 70 60 60 50 10
Kellogg 72 41 53 39 54 36 / 60 80 100 50 60 30
Moses Lake 76 45 71 44 66 40 / 20 30 10 10 40 10
Wenatchee 73 48 68 47 63 43 / 20 20 10 20 50 20
Omak 74 46 72 44 62 41 / 30 20 10 20 60 30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1137 PM CDT THU APR 21 2016
.UPDATE...LATE THIS EVENING INTO FRIDAY
ISSUED AT 1137 PM CDT THU APR 12 2016
SHOWERS AND THUNDERSTORMS HAVE ENDED ACROSS THE AREA WITH A FEW
SPRINKLES REMAINING. PLAN ON MAINLY DRY WEATHER THROUGH THE
OVERNIGHT WITH BREEZY NORTHERLY WINDS IN THE WAKE OF A COLD FRONT.
MOSTLY CLOUDY SKIES ARE EXPECTED THROUGH MID MORNING FRIDAY THEN
WE SHOULD SEE A MOSTLY SUNNY AFTERNOON WITH HIGH PRESSURE IN
CONTROL.
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 344 PM CDT THU APR 21 2016
AT 3 PM...SCATTERED SHOWERS WERE FOUND ACROSS CLARK COUNTY IN
NORTH-CENTRAL WISCONSIN AND NORTHEAST IOWA. BOTH OF THESE WERE
LOCATED ALONG A BAND OF 900 TO 800 MB FRONTOGENESIS. THERE WERE
REPORTS OF A WALL CLOUD AND PEA SIZE HAIL IN DAVENPORT/S FORECAST
AREA. THIS WAS OCCURRING IN AN AREA WHERE THE RAP WAS HIGHLIGHTING
THE NON SUPERCELL TORNADO PARAMETER /NST/. THROUGH 21.23Z...THE
RAP IS HIGHLIGHTING ANOTHER AREA OF NST ACROSS NORTHEAST IOWA AND
SOUTHWEST WISCONSIN. THERE IS A STATIONARY BOUNDARY IN THIS AREA.
HOWEVER THE RAP IS 5 TO 8F TOO HIGH WITH ITS SURFACE DEW
POINTS...THEREFORE...ITS CAPES ARE TOO HIGH. THIS IS LIKELY
ENHANCING THE NST VALUE TOO MUCH.
FOR THIS EVENING...THE 21.12Z AND 21.18Z MODELS CONTINUE TO SHOW
THAT BOTH OF THE 900 TO 800 MB FRONTOGENESIS BANDS WILL SLOWLY
MOVE SOUTHEAST AND WEAKEN. AT THE SAME TIME...THE SURFACE BASED
CAPES AND 900 TO 850 MB LAPSE RATES WILL BE WEAKENING. AS THIS
OCCURS...THE SHOWERS WILL RAPIDLY DISSIPATE BETWEEN 22.03Z AND
22.06Z.
ON FRIDAY MORNING...TEMPERATURES WILL DROP INTO THE MID-30S IN
TAYLOR COUNTY. WHILE THE TEMPERATURES WILL BE COOL FOR THE
POTENTIAL OF SCATTERED FROST...THERE WILL STILL BE A 2 TO 3F
TEMPERATURE-DEW POINT DEPRESSIONS AND THE SURFACE WINDS WILL BE IN
THE 5 TO 10 MPH RANGE. THIS SHOULD DETER THE DEVELOPMENT OF FROST
IN THAT AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 344 PM CDT THU APR 21 2016
ON FRIDAY NIGHT THERE WILL BE MOSTLY CLEAR SKIES AND LIGHT WINDS.
THIS WILL ALLOW THE LOW TEMPERATURES TO FALL INTO THE MID 30S IN
CENTRAL WISCONSIN. THIS MAY RESULT IN SOME PATCHY FROST IN THIS
AREA. WE WILL HAVE TO WATCH THIS AREA CLOSELY FOR A POTENTIAL
FROST ADVISORY.
FROM SATURDAY NIGHT THROUGH MONDAY...AN UPPER LEVEL LOW WILL MOVE
SOUTHEAST THROUGH THE REGION. ON SUNDAY AFTERNOON...THE 0-4 KM
CAPES WILL CLIMB UP TO 750 J/KG SOUTH OF INTERSTATE 90 CORRIDOR
AND THE 0-6 KM SHEAR WILL CLIMB UP TO 45 KNOTS. THIS MAY RESULT IN
THE DEVELOPMENT OF A FEW SUPERCELLS AHEAD OF THE COLD FRONT IN
NORTHEAST IOWA. WE WILL HAVE TO WATCH THIS PERIOD CLOSELY.
FROM TUESDAY NIGHT INTO WEDNESDAY...ANOTHER UPPER LEVEL LOW WILL
MOVE SOUTHEAST THROUGH THE REGION. THERE CONTINUES TO BE DEEP
SHEAR LOCATED SOUTH OF INTERSTATE 94. HOWEVER THE CAPES ARE ONLY
UP TO 500 J/KG. THIS CAPE WILL BE A LIMITING FACTOR FOR ANY THREAT
OF SEVERE WEATHER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1137 PM CDT THU APR 21 2016
A PERIOD OF MVFR CEILINGS IS EXPECTED TONIGHT IN STRATUS WITH
CLOUD BASES OF 1500 TO 2500 FT. THE STRATUS WILL THEN SHIFT SOUTH
OF THE TAF SITES BY MID TO LATE MORNING ON FRIDAY GIVING WAY TO
VFR CONDITIONS AND MOSTLY SUNNY SKIES. LOOK FOR WINDS TO BECOME
LIGHT AND VARIABLE LATE FRIDAY AFTERNOON INTO FRIDAY EVENING AS
HIGH PRESSURE BUILDS INTO THE AREA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...WETENKAMP
UPDATE...WETENKAMP
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
414 AM EDT SUN APR 24 2016
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOW RISING HEIGHTS IN
PROGRESS OVER THE FLORIDA PENINSULA EARLY THIS MORNING. THESE
HEIGHT RISES ARE OCCURRING ON THE BACKSIDE OF A DEPARTING LONGWAVE
TROUGH EXITING INTO THE WESTERN ATLANTIC. THE UPPER PATTERN IS
MUCH MORE ACTIVE OVER THE WESTERN AND CENTRAL CONUS AS A SERIES
OF UPPER DISTURBANCES CONTINUE TO ROTATE IN OFF THE PACIFIC AND
ACROSS THE CONTINENT. THE NORTHERN STREAM DISTURBANCES WILL NOT
HAVE MUCH IMPACT ON OUR WEATHER THROUGH THE FORECAST PERIOD AS
THEIR MAIN IMPACTS REMAIN WELL REMOVED FROM OUR LOCAL AREA. THERE
IS ONE WEAKER SOUTHERN STREAM IMPULSE CURRENTLY OVER NORTHERN
MEXICO THAT WILL BE MAKING SLOW PROGRESS ACROSS THE GULF OF MEXICO
THE NEXT 24-36 HOURS. WILL TALK MORE ABOUT THIS ENERGY AND ITS
POTENTIAL IMPACTS LOCALLY IN THE SHORT TERM DISCUSSION BELOW.
WATER VAPOR SHOWS LITTLE IN THE WAY OF MID/UPPER LEVEL MOISTURE
OVER THE STATE...ALLOWING FOR MOSTLY CLEAR SKIES. THE 24/00Z KTBW
SOUNDING PROFILE CONFIRMED THIS ANALYSIS...WITH A VERY DRY COLUMN
SAMPLED ABOVE 800MB...ALL THE WAY TO THE TROP.
AT THE SURFACE...HIGH PRESSURE CENTERED NEAR THE MID-ATLANTIC
COAST IS RIDGING SOUTHWARD AND BUILDING INTO OUR REGION. THIS
RIDGE WILL BE WITH US FOR THE NEXT SEVERAL DAYS AS IT SLOWLY
MIGRATES SOUTHEASTWARD. AREAS OF FOG HAVE DEVELOPED ACROSS THE
REGION SINCE MIDNIGHT. THIS IS NOT SURPRISING GIVEN THE RISING
HEIGHTS AND LARGE SCALE SUPPRESSION ONGOING OVER-TOP HIGHER LOW
LEVEL MOISTURE. THIS SETUP IS OFTEN FAVORABLE FOR GROUND FOG
DEVELOPMENT. OVERALL DO NOT ANTICIPATE WIDESPREAD DENSE
FOG...HOWEVER A FEW PATCHES OF SIGNIFICANT VISIBILITY REDUCTIONS
ARE POSSIBLE IN NORMALLY FOG PRONE AREAS THROUGH AROUND 13Z.
&&
.SHORT TERM (TODAY THROUGH MONDAY)...
AS MENTIONED ABOVE...HEIGHTS ARE RISING OVERHEAD THIS MORNING AS
MID/UPPER LEVEL RIDGING BUILDS OVER THE REGION. AT THE SAME
TIME...SURFACE HIGH PRESSURE IS RIDGING IN FROM THE NORTH/NE.
AFTER EARLY MORNING FOG PATCHES BURN OFF...WILL BE EXPECTING A
MOSTLY SUNNY MORNING WITH TEMPERATURES WARMING TOWARD 80 DEGREES
REGION-WIDE. THIS AFTERNOON...WINDS BEGIN TO SHIFT ONSHORE WITH
SEA-BREEZE DEVELOPMENT NEAR THE COAST...AND THIS WILL PROMOTE THE
DEVELOPMENT OF A FEW-SCT CUMULUS FIELD. GIVEN THE AMOUNT OF DRY
AIR ALOFT AND GENERALLY POOR MID-LEVEL LAPSE RATES...IT SEEMS
CONVECTION ALONG THE SEA- BREEZE WOULD HAVE A SIGNIFICANT
STRUGGLE. HOWEVER...VERY GOOD AGREEMENT AMONG THE CONVECTIVE
ALLOWING GUIDANCE THAT WE WILL SEE ISOLATED- SCT SHOWERS DEVELOP
LATE AFTERNOON/EARLY EVENING ALONG THE I-75 CORRIDOR. THE BEST
POTENTIAL FOR A LATE DAY SHOWER LOOKS TO BE FROM THE TAMPA BAY
AREA SOUTHWARD. SAYING SHOWER...ALTHOUGH AN ISOLATED THUNDERSTORM
CAN NOT BE RULED OUT. IN GENERAL GOING TO HAVE A HARD TIME
DEVELOPING UPDRAFTS DEEP ENOUGH FOR CHARGE SEPARATION AND
LIGHTNING...HOWEVER...A FEW STRONGER UPDRAFTS MAY BE ABLE TO
OVERCOME THE NEGATIVE DRY AIR ALOFT TO SUPPORT A THUNDERSTORM. ANY
SHOWER ACTIVITY (AND IT WILL BE SCT AT BEST) SHOULD HOLD OFF UNTIL
AFTER 20Z. HIGH TEMPERATURES THIS AFTERNOON WILL BE WELL UP INTO
THE 80S FOR MOST SPOTS AWAY FROM THE IMMEDIATE COAST. BEACHES WILL
BE A BIT COOLER WITH THE DEVELOPING ONSHORE FLOW...BUT SHOULD
STILL REACH THE LOWER 80S BEFORE THE SWITCH.
A FEW SHOWERS NEAR THE COAST IN THE EVENING DISSIPATE WITHIN A FEW
HOURS OF SUNSET AND RESULT IN A MOSTLY DRY OVERNIGHT THEREAFTER.
THE DRY CONDITIONS LEAD INTO MONDAY MORNING...WHEN A SIMILAR
FORECAST SCENARIO TO SUNDAY IS EXPECTED. THE ONLY DIFFERENCE WILL
BE THE APPROACH OF A WEAK SOUTHERN STREAM IMPULSE ACROSS THE GULF.
THIS IMPULSE WILL HELP IMPROVE/INCREASE THE MID-LEVEL LAPSE BY
1-2C/KM BY LATER MONDAY AND ALSO ADVECT SOME ADDED MOISTURE INTO
OUR COLUMN. THEREFORE...WOULD ANTICIPATE THE POTENTIAL FOR GREATER
COVERAGE OF SHOWERS OR ISOLATED STORMS AFTER 20Z. IT IS STILL
EARLY IN THE YEAR FOR SIGNIFICANT SEA-BREEZE CONVECTION...SO WILL
NOT GO MUCH ABOVE 30-40% POPS...HOWEVER...WILL NEED TO KEEP AN EYE
ON THE GUIDANCE SINCE THE ENERGY ALOFT WILL CERTAINLY LESSEN THE
CONVECTIVE INHIBITION.
&&
.MID/LONG TERM (MONDAY THROUGH NEXT SATURDAY)...
A LATE APRIL WEATHER PATTERN IS CERTAINLY IN PLACE ACROSS WEST
CENTRAL AND SW FLORIDA THIS WEEK AS TEMPERATURES WILL BE WARM WITH
LITTLE TO NO PRECIP EXPECTED. SURFACE HIGH PRESSURE WILL SHIFT OFF
THE EASTERN SEABOARD TO BEGIN THE WEEK AND REMAIN IN PLACE THROUGH
THE FORECAST PERIOD. THIS WILL KEEP OUR WEATHER FAIRLY QUIET
ALTHOUGH WARMER THAN NORMAL. WARM TEMPERATURES AND LIGHT STEERING
FLOW SHOULD ALLOW FOR DAILY SEABREEZES HOWEVER WITH PWAT VALUES IN
THE 1-1.25 INCH RANGE THERE IS NOT GOING TO BE A LOT OF MOISTURE
TO WORK WITH SO WILL KEEP RAIN CHANCES BELOW 20 PERCENT THOUGH THE
PERIOD. IT IS CERTAINLY POSSIBLE THAT MAYBE A STRAY SHALLOW SHOWER
MAY POP UP ALONG THE SEABREEZE BUT MOST OF THE AREA WILL REMAIN
DRY. AFTERNOON HIGH TEMPS ARE EXPECTED IN THE MID TO UPPER 80S FOR
MUCH OF THE WEEK WITH MAYBE A FEW INLAND LOCATIONS REACHING 90 BY
LATE WEEK...COOLER AT THE COAST WITH DAILY SEABREEZES.
&&
.AVIATION...
AREAS OF FOG HAVE ALREADY DEVELOPED EARLY THIS MORNING. A PERIOD
OF MVFR/IFR VISIBILITY MAY OCCUR AT ANY TIME THROUGH 13Z...
ESPECIALLY FOR KLAL AND KPGD. ONCE ANY EARLY MORNING FOG PATCHES
BURN OFF...VFR CONDITIONS WILL GENERALLY PREVAIL FOR ALL TERMINALS
THROUGH THE TAF PERIOD. AS THE SEA- BREEZE MOVES INLAND LATE THIS
AFTERNOON... THERE WILL BE A LOW CHANCE FOR A BRIEF SHOWER OR
STORM AT ANY OF THE TERMINALS...MAINLY AFTER 20Z.
&&
.MARINE...
HIGH PRESSURE OVER THE WESTERN ATLANTIC WILL RIDGE BACK WESTWARD
OVER THE EASTERN GULF OF MEXICO THROUGH THE MIDDLE OF THE WEEK.
WINDS AND SEAS WILL GENERALLY REMAIN BELOW HEADLINE CRITERIA
THROUGH THE FORECAST PERIOD. EXPECT WINDS TO SHIFT ONSHORE NEAR
THE COAST EACH DAY WITH SEABREEZE FORMATION. A FEW LATE AFTERNOON
OR EVENING THUNDERSTORMS ARE POSSIBLE NEAR THE COAST TODAY AND
AGAIN MONDAY. STORM COVERAGE WILL BE LOW...HOWEVER BOATERS SHOULD
KEEP AN EYE TO THE EAST LATE IN THE DAY AS ANY STORMS THAT DO
DEVELOP OVER LAND WILL TEND TO MIGRATE OFFSHORE.
&&
.FIRE WEATHER...
HIGH PRESSURE RIDGES OVER THE STATE THROUGH THE EARLY PORTION OF
THE WEEK. WINDS WILL GENERALLY REMAIN LIGHT...SHIFTING ONSHORE
NEAR THE COAST EACH AFTERNOON. MINIMUM RELATIVE HUMIDITY VALUES
BOTH SUNDAY AND MONDAY AFTERNOONS WILL BRIEFLY APPROACH 35
PERCENT...HOWEVER EXTENDED DURATIONS ARE NOT EXPECTED...AND WINDS
WILL REMAIN BELOW CRITICAL LEVELS...PREVENTING RED FLAG CONDITIONS.
THERE WILL BE A LOW CHANCE FOR A BRIEF LATE AFTERNOON OR EVENING
SHOWER THE NEXT SEVERAL AFTERNOON AS THE SEA-BREEZE PUSHES INLAND.
FOG POTENTIAL...AREAS OF FOG EARLY THIS MORNING WILL BURN OFF WITHIN
A FEW HOURS OF SUNRISE. NO SIGNIFICANT FOG CONCERNS ARE THEN
ANTICIPATED THROUGH MONDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 84 68 85 68 / 30 30 30 20
FMY 87 67 85 66 / 40 40 30 20
GIF 85 66 84 64 / 10 10 30 10
SRQ 80 67 81 66 / 30 30 20 10
BKV 85 63 84 61 / 20 20 30 10
SPG 84 69 83 69 / 40 40 20 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
MID TERM/LONG TERM/DECISION SUPPORT...MCKAUGHAN
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
425 AM EDT SUN APR 24 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 424 AM EDT SUN APR 24 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW A CONFLUENT WNW
FLOW ALF OVER THE UPR LKS BTWN A NRN BRANCH CUTOFF LO OVER NRN
QUEBEC AND A SRN BRANCH FLOW DOMINATING THE CONUS WITH A STRONG
SHRTWV IN THIS FLOW DRIFTING SLOWLY ENEWD THRU WYOMING. THERE IS A
GOOD DEAL OF CLD COVER OVER UPR MI WITH WAA IN TIGHTENING BAROCLINIC
ZN TO THE NE OF H85 WARM FNT STRETCHING FM THE NRN PLAINS INTO WRN
WI...BUT AXIS OF HEAVIEST RA EARLY THIS MRNG STRETCHES FM NCENTRAL
MN ESEWD INTO NCENTRAL WI CLOSER TO THE H85 FNT. THERE ARE MORE SCT
RA SHOWERS DVLPG IN NRN MN WHERE UPR DVGC IN RRQ OF 120KT H3 JET
CORE CENTERED JUST SW OF JAMES BAY IS AIDING LIFT OF MOISTER AIR
SHOWN ON THE 00Z INL RAOB. LINGERING LLVL DRY AIR SHOWN ON THE 00Z
GRB/APX RAOBS THAT IS REPRESENTATIVE OF CONDITIONS OVER THE CWA HAS
SLOWED DOWN THE ARRIVAL OF THIS EXPANDING PCPN AND THE NE PUSH OF
THE RA IN WI CLOSER TO THE H85 WARM FNT. THE AIR IN ONTARIO IS EVEN
DRIER WITH 00Z PWAT AS LO AS 0.14 INCH AT YPL.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/QPF ASSOCIATED
WITH TIGHTENING BAROCLINIC ZN OVER UPR MI UNDER PERSISTENT UPR DVGC
IN RRQ OF H3 JET MAX MOVING ONLY SLOWLY E THRU TNGT. CLOSER APRCH
TNGT OF SHRTWV NOW IN WYOMING WILL INTENSIFY THE DYNAMIC SUPPORT.
CONFIDENCE IS INCRSG THE HEAVIER RA WL FALL NEAR THE WI BORDER...BUT
THERE ARE STILL SOME MODEL INCONSISTENCIES AS TO THE PLACEMENT OF
THE AXIS OF HEAVIER RA RELATED TO POSITION OF SHARPER FGEN AND
IMPACT OF DRY AIR TO THE N.
TDAY...H85 THERMAL GRADIENT/UPR DVGC IN RRQ OF UPR JET CORE TO THE
NE IS FCST TO EXPAND OVER UPR MI TODAY...AND MOST OF THE MODELS
SHIFT AXIS OF HEAVIER PCPN TO THE N ACCORDINGLY. SO WL EXPAND HIER
POPS NE THRU THE CWA EXCEPT OVER THE KEWEENAW...WHICH WL BE CLOSER
TO THE DEEPER DRY AIR JUST TO THE N. HOWEVER...WITH LINGERING LLVL
DRY AIR...FAVOR THE 00Z REGIONAL CNDN MODEL FCST. THIS MODEL SHOWS
THE HIER QPF REMAINING CLOSER TO THE WI BORDER WHERE EVEN THE 00Z
NAM SHOWS MORE PERSISTENT AXIS OF SHARPER H85-7 FGEN/UVV AND WHERE
PWAT IS FCST TO INCRS TO AOA 1 INCH /ABOUT 225 PCT OF NORMAL/. THIS
FCST IS ALSO MORE CONSISTENT WITH LOCATION OF AXIS OF HEAVIER RA FM
NCENTRAL MN INTO NCENTRAL WI EARLY THIS MRNG...THE LOCATION OF WHICH
MAY HINT AT A BNDRY WHICH MAY ACT TO INTERCEPT MSTR INFLOW. WITH THE
CLDS AND RA DVLPG...EXPECT WELL BLO NORMAL MAX TEMPS THAT WL LIKELY
STAY UNDER 40 AT SOME PLACES NEAR LK SUP.
TNGT...WITH SLOW APRCH OF SHRTWV FM THE WSW TNGT...UPR DVGC OVER AND
MSTR TRANSPORT INTO ARE FCST TO INCRS OVERNGT. SO EXPECT HEAVIER RA
TO EXPAND TO THE NE. THE CNDN MODEL STILL SEEMS TO BE ON THE RIGHT
TRACK SHOWING THE AXIS OF HEAVIER PCPN DIMINISHING A BIT WITH THE
SHIFT TO THE NE GIVEN PERSISTENT DRY AIR IN THAT DIRECTION THAT WILL
TEND TO SHARPEN THE NRN EDGE OF THE PCPN/HEAVIER RA. TOTAL RA THRU
12Z MON WL REACH AS MUCH AS 1.50 TO 2.00 INCHES NEAR THE WI BORDER.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 413 AM EDT SUN APR 24 2016
SHORTWAVE TROUGH LIFTING ACROSS THE NORTHERN PLAINS COMBINES WITH
SHARP H85 BAROCLINIC ZONE TO SUPPORT MODERATE PERHAPS HEAVY RAIN
MONDAY MORNING. SINCE STRONGEST H85 TEMP GRADIENT AND ASSOCIATED
FRONTOGENSIS REMAINS OVER SOUTHERN TIER OF UPR MICHIGAN...PERFER
MODEL SOLUTIONS THAT DIMINISH QPF AS IT LIFTS OVER NORTHERN TIER
OF CWA IN THE MORNING. GFS AND GEM-REGIONAL FIT INTO THAT CATEGORY.
QUITE A COOL AND DAMP DAY ON MON NO MATTER THE COVERAGE OF THE RAIN.
EXPECT CHILLY READINGS IN THE MID-UPR 30S NEAR LK SUPERIOR AND
ONLY AROUND 40 ELSEWHERE.
PRIMARY SHORTWAVE TROUGH ARRIVES OVER UPPER GREAT LAKES ON MONDAY
AFTN. JET STREAK ROUNDING BASE OF TROUGH AND SOME ELEVATED
INSTABILITY MAY RESULT IN TSRA POSSIBLY SNEAKING INTO SCNTRL CWA
LATE MONDAY AFTN INTO MONDAY EVENING. DID KEEP MENTION OF TSRA OUT
ATTM AS WITH SFC LOW PASSING BY SOUTH OF UPR MICHIGAN...WOULD EXPECT
BEST CHANCES FOR EVEN ELEVATED TSRA OVER EASTERN WI AND ON FARTHER
SOUTH. ARRIVAL OF THE SHORTWAVE TROUGH SHOULD BRING ANOTHER ROUND OF
RAIN TO MAINLY THE SOUTH AND SOUTH CENTRAL IN THE AFTN. COOLER AIR
WORKS ACROSS UPR MICHIGAN MON EVENING AS THE LOW OVER WI SLIDES
EAST. 1000-500MB/850-700MB THICKNESSES AND NAM/GFS SOUNDINGS
INDICATE POTENTIAL FOR SNOW TO BEGIN MIXING WITH RAIN OVER HIGHER
TERRAIN OF NW AND NCNTRL MON EVENING THEN SWITCH OVER TO SNOW
OVERNIGHT MON NIGHT. SINCE THE ARRIVAL OF THE COLD AIR TIMES OUT
WITH DIMINISHING PRECIPITATION...SNOW AMOUNTS MON NIGHT SHOULD STAY
LESS THAN AN INCH...MAINLY ON GRASSY SURFACES.
AFTER THE RAIN/SNOW TO SNOW MOVES OUT LATE MON NIGHT...LOOKS DRY
THROUGH THE REST OF THE WEEK AND INTO NEXT WEEKEND AS HIGH PRESSURE
BUILDS OVER HUDSON BAY AND PERSISTS. DRY EASTERLY FLOW SHOULD KEEP
UPPER MICHIGAN DRY. WITH THE EAST TO NORTHEAST WIND OFF THE HIGH
COOLEST READINGS DURING THE DAYTIME SHOULD BE NEAR LK SUPERIOR.
TEMPS THERE LIKELY WILL REMAIN SLIGHTLY BELOW NORMAL THROUGH THE
WEEK. INLAND TEMPS AND NEAR LK MICHIGAN SHOULD REACH TOWARD NORMAL
BY MID TO LATE WEEK WITH READINGS IN THE 50S TO NEAR 60 BY LATE IN
THE WEEK. INFLUENCE OF THE DRY HIGH PRESSURE SHOULD ALLOW TEMPS AT
NIGHT AWAY FROM THE GREAT LAKES TO FALL INTO THE 20S TO LOW 30S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 121 AM EDT SUN APR 24 2016
VFR CONDITIONS WILL HOLD ON UNTIL LATE TONIGHT AT ALL SITES UNDER
MID LEVEL CLOUDS. LIGHT RAIN WILL ARRIVE AND WILL CONTINUE THROUGH
THE REST OF THE FORECAST PERIOD. ONCE THE RAIN ARRIVES...CIGS WILL
STEADILY LOWER...REACHING IFR AT ALL TERMINALS AFTER 12Z. CONDITIONS
SHOULD CONTINUE TO DETERIORATE FURTHER TO LIFR/VLIFR DURING THE
MORNING HRS AND WILL CONTINUE THAT WAY THE REST OF THE FORECAST
PERIOD AT ALL SITES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 AM EDT SUN APR 24 2016
WITH TIGHTENING PRES GRADIENT BETWEEN HI PRES BUILDING INTO NORTHERN
ONTARIO AND A LO PRES MOVING E FROM THE PLAINS ALONG A STALLED LO
PRES TROUGH TO THE S...EXPECT NE WINDS INCREASING TO 25 TO 30 KTS
THRU MON. THE STRONGEST WINDS WILL BE OVER THE WESTERN LAKE...WHERE
GALES TO 35-40 KTS ARE FORECAST THIS AFTERNOON THRU MON WITH A
COASTLINE CONFIGURATION THAT WILL ACCENTUATE THE NE FLOW. EXPANDED
THE GALE WARNING FOR LSZ162 TO INCLUDE LSZ263 FOR LATE TONIGHT AND
MON. WINDS WILL GRADUALLY DIMINISH MON NIGHT THRU TUE AS A HI PRES
BUILDS INTO THE UPPER LAKES. N TO E WINDS GENERALLY UNDER 20 KTS WILL
THEN PREVAIL ON WED AND THU WITH A HI PRES RIDGE AXIS IN PLACE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 11 AM EDT /10 AM CDT/ THIS MORNING TO 8 PM EDT
/7 PM CDT/ MONDAY FOR LSZ162.
GALE WARNING FROM 5 AM TO 8 PM EDT MONDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...07
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
413 AM EDT SUN APR 24 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 424 PM EDT SAT APR 23 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW SPLIT FLOW OVER NAMERICA.
IN THE NRN STREAM...A TROF EXTENDS THRU HUDSON BAY INTO SE CANADA
BTWN RIDGING OVER WRN CANADA AND A CLOSED MID LEVEL HIGH CENTERED
JUST SE OF GREENLAND. IN THE SRN STREAM...A TROF IS OVER THE WRN
CONUS WITH RIDGING OUT OVER THE PLAINS. JET STREAK DEVELOPING IN THE
CONFLUENCE BTWN THE SRN STREAM RIDGE AND NRN STREAM TROF OVER SE
CANADA WILL BE ONE OF THE MAIN PLAYERS IN THE WET WEATHER SETTING UP
ACROSS UPPER MI FOR THE NEXT 36-48HRS. WELL OUT AHEAD OF THE WRN
CONUS TROF...WAA/ISENTROPIC ASCENT REGIME SRPEADING OVER THE NRN
PLAINS HAS LED TO SCT -SHRA DEVELOPMENT FROM ND ACROSS NE MN
THIS AFTN. MID CLOUDS ARE PEELING SE FROM THAT AREA ACROSS UPPER MI.
ALTHOUGH CLOUDS HAVE WORKED TO SOMEWHAT LIMIT THE NORMAL DIURNAL
BUILDING OF MIXING HEIGHTS...SFC DWPTS HAVE STILL FALLEN DOWN INTO
THE SINGLE DIGITS/LOW TEENS ACROSS PORTIONS OF INTERIOR W AND CNTRL
UPPER MI.
A GOOD PATTERN FOR SOAKING RAINS WILL BE SETTING UP ACROSS THE AREA
OVER THE NEXT 36-48HRS AS FCST AREA WILL RESIDE IN A SHARP
BAROCLINIC ZONE RESULTING FROM COLD AIR SPREADING ACROSS SE CANADA
UNDER NRN STREAM TROF AND WARM AIR PUSHING TOWARD THE UPPER
MISSISSIPPI VALLEY AHEAD OF THE SRN STREAM WRN CONUS TROF. IN
FACT...MOST OF THE FCST AREA WILL SEE MDT TO HVY RAINFALL AMOUNTS BY
THE TIME THIS WET PERIOD WRAPS UP MON NIGHT. AFOREMENTIONED JET
STREAK WILL BE A KEY MECHANISM FOR PCPN GENERATION AS THE RIGHT
ENTRANCE WILL PROVIDE LARGER SCALE UPPER DIVERGENCE OVER THE AREA.
AT THE LOWER LEVELS...850MB FRONT SETTING UP IN THE VCNTY OF THE
MI/WI BORDER WILL PROVIDE A FOCUS FOR PCPN DEVELOPMENT UNDER
PERSISTENT FGEN/ISENTROPIC ASCENT. PRECIPITABLE WATER INCREASING TO
AROUND 1 INCH (200-250PCT OF NORMAL) WILL THEN SUPPORT THE EXPECTED
MDT/HVY PCPN AMOUNTS. UTILIZED A MIX OF ALL AVBL MODELS TO CONSTRUCT
POPS/PCPN AMOUNTS FOR TONIGHT/SUN AS MOST OF THE GUIDANCE IS FAIRLY
WELL CLUSTERED ON QPF AND TIMING ONSET OF RAIN. PCPN DEVELOPMENT
TONIGHT MAY BE DELAYED MORE SO THAN REFLECTED IN FCST DUE TO THE
VERY DRY AIR OVER THE AREA ATTM. BY 00Z MON...EXPECT PCPN AMOUNTS
RANGING FROM AROUND ONE-THIRD OF AN INCH OVER THE NRN KEWEENAW
PENINSULA AND NE LUCE COUNTY TO 0.90-1.25 INCHES OVER MUCH OF THE W
AND CNTRL FCST AREA. AS FOR TEMPS...LOWS TONIGHT SHOULD RANGE FROM
THE MID 30S TO LWR 40S...WARMEST FAR W. WITH EXPECTATION OF RAIN
PREVAILING FOR MUCH OF THE DAY IN MOST AREAS...LOWERED MAX TEMPS
SOME FOR SUN. HIGHS SHOULD RANGE FROM THE UPPER 30S NW AND NCNTRL TO
MAINLY THE LWR 40S ELSEWHERE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 413 AM EDT SUN APR 24 2016
SHORTWAVE TROUGH LIFTING ACROSS THE NORTHERN PLAINS COMBINES WITH
SHARP H85 BAROCLINIC ZONE TO SUPPORT MODERATE PERHAPS HEAVY RAIN
MONDAY MORNING. SINCE STRONGEST H85 TEMP GRADIENT AND ASSOCIATED
FRONTOGENSIS REMAINS OVER SOUTHERN TIER OF UPR MICHIGAN...PERFER
MODEL SOLUTIONS THAT DIMINISH QPF AS IT LIFTS OVER NORTHERN TIER
OF CWA IN THE MORNING. GFS AND GEM-REGIONAL FIT INTO THAT CATEGORY.
QUITE A COOL AND DAMP DAY ON MON NO MATTER THE COVERAGE OF THE RAIN.
EXPECT CHILLY READINGS IN THE MID-UPR 30S NEAR LK SUPERIOR AND
ONLY AROUND 40 ELSEWHERE.
PRIMARY SHORTWAVE TROUGH ARRIVES OVER UPPER GREAT LAKES ON MONDAY
AFTN. JET STREAK ROUNDING BASE OF TROUGH AND SOME ELEVATED
INSTABILITY MAY RESULT IN TSRA POSSIBLY SNEAKING INTO SCNTRL CWA
LATE MONDAY AFTN INTO MONDAY EVENING. DID KEEP MENTION OF TSRA OUT
ATTM AS WITH SFC LOW PASSING BY SOUTH OF UPR MICHIGAN...WOULD EXPECT
BEST CHANCES FOR EVEN ELEVATED TSRA OVER EASTERN WI AND ON FARTHER
SOUTH. ARRIVAL OF THE SHORTWAVE TROUGH SHOULD BRING ANOTHER ROUND OF
RAIN TO MAINLY THE SOUTH AND SOUTH CENTRAL IN THE AFTN. COOLER AIR
WORKS ACROSS UPR MICHIGAN MON EVENING AS THE LOW OVER WI SLIDES
EAST. 1000-500MB/850-700MB THICKNESSES AND NAM/GFS SOUNDINGS
INDICATE POTENTIAL FOR SNOW TO BEGIN MIXING WITH RAIN OVER HIGHER
TERRAIN OF NW AND NCNTRL MON EVENING THEN SWITCH OVER TO SNOW
OVERNIGHT MON NIGHT. SINCE THE ARRIVAL OF THE COLD AIR TIMES OUT
WITH DIMINISHING PRECIPITATION...SNOW AMOUNTS MON NIGHT SHOULD STAY
LESS THAN AN INCH...MAINLY ON GRASSY SURFACES.
AFTER THE RAIN/SNOW TO SNOW MOVES OUT LATE MON NIGHT...LOOKS DRY
THROUGH THE REST OF THE WEEK AND INTO NEXT WEEKEND AS HIGH PRESSURE
BUILDS OVER HUDSON BAY AND PERSISTS. DRY EASTERLY FLOW SHOULD KEEP
UPPER MICHIGAN DRY. WITH THE EAST TO NORTHEAST WIND OFF THE HIGH
COOLEST READINGS DURING THE DAYTIME SHOULD BE NEAR LK SUPERIOR.
TEMPS THERE LIKELY WILL REMAIN SLIGHTLY BELOW NORMAL THROUGH THE
WEEK. INLAND TEMPS AND NEAR LK MICHIGAN SHOULD REACH TOWARD NORMAL
BY MID TO LATE WEEK WITH READINGS IN THE 50S TO NEAR 60 BY LATE IN
THE WEEK. INFLUENCE OF THE DRY HIGH PRESSURE SHOULD ALLOW TEMPS AT
NIGHT AWAY FROM THE GREAT LAKES TO FALL INTO THE 20S TO LOW 30S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 121 AM EDT SUN APR 24 2016
VFR CONDITIONS WILL HOLD ON UNTIL LATE TONIGHT AT ALL SITES UNDER
MID LEVEL CLOUDS. LIGHT RAIN WILL ARRIVE AND WILL CONTINUE THROUGH
THE REST OF THE FORECAST PERIOD. ONCE THE RAIN ARRIVES...CIGS WILL
STEADILY LOWER...REACHING IFR AT ALL TERMINALS AFTER 12Z. CONDITIONS
SHOULD CONTINUE TO DETERIORATE FURTHER TO LIFR/VLIFR DURING THE
MORNING HRS AND WILL CONTINUE THAT WAY THE REST OF THE FORECAST
PERIOD AT ALL SITES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 PM EDT SAT APR 23 2016
A CLASSIC SET UP FOR BRISK E TO NE WINDS IS SHAPING UP FOR LAKE
SUPERIOR OVER THE NEXT COUPLE OF DAYS AS HIGH PRES BUILDS INTO
NORTHERN ONTARIO AND A WEAK LOW PRES WAVE TRACKS ALONG A FRONT S OF
UPPER MI. WINDS INITIALLY UNDER 20KT THIS EVENING WILL SLOWLY RAMP
UP TONIGHT...MAINLY OVER WESTERN LAKE SUPERIOR. WINDS THEN INCREASE
MORE NOTABLY ACROSS THE LAKE SUN THRU MON MORNING...REACHING GALES
OVER FAR WESTERN LAKE SUPERIOR LATE SUN MORNING THRU MON AFTN AS
COASTAL CONVERGENCE/FUNNELING ENHANCE THE WINDS IN THAT AREA. A GALE
WARNING HAS BEEN POSTED FOR THAT PART OF THE LAKE. ACROSS THE REST
OF LAKE SUPERIOR...WINDS WILL INCREASE TO 20-30KT. WINDS WILL SLOWLY
DIMINISH MON NIGHT/TUE MORNING...BUT MORE SO TUE AFTN/NIGHT AS THE
NORTHERN ONTARIO HIGH PRES BUILDS INTO THE UPPER LAKES. E TO NE
WINDS GENERALLY UNDER 20KT WILL PREVAIL WED/THU. GIVEN THE E TO NE
WIND DIRECTION...WINDS WILL BE STRONGEST OVER WRN LAKE SUPERIOR ON
BOTH OF THOSE DAYS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 11 AM EDT /10 AM CDT/ THIS MORNING TO 8 PM EDT
/7 PM CDT/ MONDAY FOR LSZ162.
GALE WARNING FROM 5 AM TO 8 PM EDT MONDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
122 AM EDT SUN APR 24 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 424 PM EDT SAT APR 23 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW SPLIT FLOW OVER NAMERICA.
IN THE NRN STREAM...A TROF EXTENDS THRU HUDSON BAY INTO SE CANADA
BTWN RIDGING OVER WRN CANADA AND A CLOSED MID LEVEL HIGH CENTERED
JUST SE OF GREENLAND. IN THE SRN STREAM...A TROF IS OVER THE WRN
CONUS WITH RIDGING OUT OVER THE PLAINS. JET STREAK DEVELOPING IN THE
CONFLUENCE BTWN THE SRN STREAM RIDGE AND NRN STREAM TROF OVER SE
CANADA WILL BE ONE OF THE MAIN PLAYERS IN THE WET WEATHER SETTING UP
ACROSS UPPER MI FOR THE NEXT 36-48HRS. WELL OUT AHEAD OF THE WRN
CONUS TROF...WAA/ISENTROPIC ASCENT REGIME SRPEADING OVER THE NRN
PLAINS HAS LED TO SCT -SHRA DEVELOPMENT FROM ND ACROSS NE MN
THIS AFTN. MID CLOUDS ARE PEELING SE FROM THAT AREA ACROSS UPPER MI.
ALTHOUGH CLOUDS HAVE WORKED TO SOMEWHAT LIMIT THE NORMAL DIURNAL
BUILDING OF MIXING HEIGHTS...SFC DWPTS HAVE STILL FALLEN DOWN INTO
THE SINGLE DIGITS/LOW TEENS ACROSS PORTIONS OF INTERIOR W AND CNTRL
UPPER MI.
A GOOD PATTERN FOR SOAKING RAINS WILL BE SETTING UP ACROSS THE AREA
OVER THE NEXT 36-48HRS AS FCST AREA WILL RESIDE IN A SHARP
BAROCLINIC ZONE RESULTING FROM COLD AIR SPREADING ACROSS SE CANADA
UNDER NRN STREAM TROF AND WARM AIR PUSHING TOWARD THE UPPER
MISSISSIPPI VALLEY AHEAD OF THE SRN STREAM WRN CONUS TROF. IN
FACT...MOST OF THE FCST AREA WILL SEE MDT TO HVY RAINFALL AMOUNTS BY
THE TIME THIS WET PERIOD WRAPS UP MON NIGHT. AFOREMENTIONED JET
STREAK WILL BE A KEY MECHANISM FOR PCPN GENERATION AS THE RIGHT
ENTRANCE WILL PROVIDE LARGER SCALE UPPER DIVERGENCE OVER THE AREA.
AT THE LOWER LEVELS...850MB FRONT SETTING UP IN THE VCNTY OF THE
MI/WI BORDER WILL PROVIDE A FOCUS FOR PCPN DEVELOPMENT UNDER
PERSISTENT FGEN/ISENTROPIC ASCENT. PRECIPITABLE WATER INCREASING TO
AROUND 1 INCH (200-250PCT OF NORMAL) WILL THEN SUPPORT THE EXPECTED
MDT/HVY PCPN AMOUNTS. UTILIZED A MIX OF ALL AVBL MODELS TO CONSTRUCT
POPS/PCPN AMOUNTS FOR TONIGHT/SUN AS MOST OF THE GUIDANCE IS FAIRLY
WELL CLUSTERED ON QPF AND TIMING ONSET OF RAIN. PCPN DEVELOPMENT
TONIGHT MAY BE DELAYED MORE SO THAN REFLECTED IN FCST DUE TO THE
VERY DRY AIR OVER THE AREA ATTM. BY 00Z MON...EXPECT PCPN AMOUNTS
RANGING FROM AROUND ONE-THIRD OF AN INCH OVER THE NRN KEWEENAW
PENINSULA AND NE LUCE COUNTY TO 0.90-1.25 INCHES OVER MUCH OF THE W
AND CNTRL FCST AREA. AS FOR TEMPS...LOWS TONIGHT SHOULD RANGE FROM
THE MID 30S TO LWR 40S...WARMEST FAR W. WITH EXPECTATION OF RAIN
PREVAILING FOR MUCH OF THE DAY IN MOST AREAS...LOWERED MAX TEMPS
SOME FOR SUN. HIGHS SHOULD RANGE FROM THE UPPER 30S NW AND NCNTRL TO
MAINLY THE LWR 40S ELSEWHERE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 511 PM EDT SAT APR 23 2016
COOL CONDITIONS ARE EXPECTED THROUGH THE UPCOMING WEEK...WITH HEAVY
RAIN EXPECTED THROUGH MONDAY.
SUNDAY NIGHT AND MONDAY NIGHT...A STOUT BAROCLINIC ZONE STRETCHING
FROM THE NORTHERN PLAINS TO THE LOWER GREAT LAKES WILL BE THE FOCUS
FOR AN ONGOING ACTIVE PERIOD OF WEATHER. SUBSTANTIAL LOW TO MID-
LEVEL FGEN...WAA...AND LOW-LEVEL MOISTURE TRANSPORT WILL BRING A
CONTINUOUS FEED OF PRECIP ACROSS THE CWA THROUGH AT LEAST MONDAY
MORNING. PWATS APPROACHING 1.5 INCHES ACROSS MN TRACKING TOWARD THE
AREA IN CONJUNCTION WITH AN APPROACHING RIGHT ENTRANCE TO AN UPPER
JET WILL SUPPORT A PERIOD OF MODERATE TO HEAVY RAIN ACROSS ALL BUT
THE KEWEENAW PENINSULA SUNDAY EVENING INTO THE OVERNIGHT HOURS.
MODEL QPF SUNDAY NIGHT ADVERTISES A STRIPE OF 1 TO 2 INCHES WITH
ISOLATED 3 INCH TOTALS ACROSS THE CWA. CURRENT THINKING PUTS THE
HEAVIEST RAIN ALONG A LINE FROM FAR NW WI TO NORTHERN LAKE
MI...INCLUDING IWD...IMT...AND ESC. HOWEVER...MODEL GUIDANCE
CONTINUES TO TREND NORTHWARD WITH THIS SET-UP. IN FACT...LAST
WEEK...LONG TERM GUIDANCE PLACED ALL OF UPPER MI ON THE COLD AND DRY
SIDE OF THE BAROCLINIC ZONE. GIVEN THE MODEL TRENDS...HAVE CONTINUED
THE NORTHWARD PROGRESSION OF THE HIGHEST QPF SUNDAY NIGHT.
AS THE LOW-LEVEL SYSTEM PASSES TO THE SOUTH ON MONDAY...MID-LEVEL
FGEN WILL BE ENHANCED ACROSS THE CWA. THIS WILL FAVOR CONTINUED
MODERATE RAINFALL THROUGH THE MORNING AND POSSIBLY INTO THE
AFTERNOON ACROSS THE SOUTH HALF OF THE CWA. WEAKER FORCING AND DRIER
AIR FILTERING ACROSS THE AREA MONDAY AFTERNOON INTO MONDAY NIGHT
WILL ALLOW FOR A GRADUAL DIMINISHING TREND IN PRECIP AND CLOUD COVER
FROM NORTH TO SOUTH.
WITH THE NORTHWARD TREND IN MODEL GUIDANCE...THE PROSPECTS OF
APPRECIABLE ACCUMULATING SNOW CONTINUE TO DIMINISH. FORECAST
SOUNDINGS INDICATE SLIGHTLY ABOVE FREEZING TEMPS ACROSS THE CWA
THROUGH SUNDAY NIGHT. AS DRYING AND SOME COLDER AIR WORK IN FROM THE
NORTH ON MONDAY...PRECIP MAY SWITCH OVER TO SNOW ACROSS THE HIGH
TERRAIN OF THE NORTH. HOWEVER...WITH A BULK OF THE PRECIP OVER...AND
WITH LATE APRIL DAYTIME HEATING PRESENT...DO NOT EXPECT ANYTHING
MORE THAN UP TO A SLUSHY INCH OF ACCUMULATION ON GRASSY SURFACES
DURING THE DAY.
FORECAST STORM TOTAL QPF TONIGHT THROUGH MONDAY PLACES A SWATH OF 2
TO 3 INCHES SOUTH OF A LINE FROM ONTONAGON TO MARQUETTE TO ST
IGNACE. AMOUNTS QUICKLY DROP OFF TO THE NORTH...WITH LESS THAN A
HALF INCH EXPECTED FOR COPPER HARBOR. GIVEN THE WIDE VARIETY OF QPF
PLACEMENT AMONG MODELS AND ENSEMBLES...IT MUST BE NOTED THAT
LOCALIZED AMOUNTS IN EXCESS OF 4 INCHES WILL BE POSSIBLE THROUGH THE
AFOREMENTIONED PERIOD. GIVEN THE RECENT DRY PERIOD...FLOODING
CONCERNS ARE SOMEWHAT EASED. HOWEVER...WITH LITTLE TO NO
GREENUP...SOILS WILL BECOME SATURATED QUICKLY. HAVE DECIDED TO ISSUE
AN SPS TO ACCOUNT FOR POTENTIALLY VERY HEAVY RAIN AND ELEVATED RIVER
LEVELS THROUGH THE UPCOMING WEEK.
FOR THE REMAINDER OF THE WEEK...COOL AND MOSTLY DRY CONDITIONS WILL
PREVAIL AS HIGH PRESSURE RIDGING EDGES FROM NORTHERN ONTARIO INTO
THE UPPER GREAT LAKES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 121 AM EDT SUN APR 24 2016
VFR CONDITIONS WILL HOLD ON UNTIL LATE TONIGHT AT ALL SITES UNDER
MID LEVEL CLOUDS. LIGHT RAIN WILL ARRIVE AND WILL CONTINUE THROUGH
THE REST OF THE FORECAST PERIOD. ONCE THE RAIN ARRIVES...CIGS WILL
STEADILY LOWER...REACHING IFR AT ALL TERMINALS AFTER 12Z. CONDITIONS
SHOULD CONTINUE TO DETERIORATE FURTHER TO LIFR/VLIFR DURING THE
MORNING HRS AND WILL CONTINUE THAT WAY THE REST OF THE FORECAST
PERIOD AT ALL SITES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 PM EDT SAT APR 23 2016
A CLASSIC SET UP FOR BRISK E TO NE WINDS IS SHAPING UP FOR LAKE
SUPERIOR OVER THE NEXT COUPLE OF DAYS AS HIGH PRES BUILDS INTO
NORTHERN ONTARIO AND A WEAK LOW PRES WAVE TRACKS ALONG A FRONT S OF
UPPER MI. WINDS INITIALLY UNDER 20KT THIS EVENING WILL SLOWLY RAMP
UP TONIGHT...MAINLY OVER WESTERN LAKE SUPERIOR. WINDS THEN INCREASE
MORE NOTABLY ACROSS THE LAKE SUN THRU MON MORNING...REACHING GALES
OVER FAR WESTERN LAKE SUPERIOR LATE SUN MORNING THRU MON AFTN AS
COASTAL CONVERGENCE/FUNNELING ENHANCE THE WINDS IN THAT AREA. A GALE
WARNING HAS BEEN POSTED FOR THAT PART OF THE LAKE. ACROSS THE REST
OF LAKE SUPERIOR...WINDS WILL INCREASE TO 20-30KT. WINDS WILL SLOWLY
DIMINISH MON NIGHT/TUE MORNING...BUT MORE SO TUE AFTN/NIGHT AS THE
NORTHERN ONTARIO HIGH PRES BUILDS INTO THE UPPER LAKES. E TO NE
WINDS GENERALLY UNDER 20KT WILL PREVAIL WED/THU. GIVEN THE E TO NE
WIND DIRECTION...WINDS WILL BE STRONGEST OVER WRN LAKE SUPERIOR ON
BOTH OF THOSE DAYS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 11 AM EDT /10 AM CDT/ THIS MORNING TO 8 PM EDT
/7 PM CDT/ MONDAY FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KLUBER
AVIATION...07
MARINE...ROLFSON
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
417 AM CDT SUN APR 24 2016
.Discussion...
Issued at 417 AM CDT SUN APR 24 2016
Today - Tonight:
The first in a series of upper level systems will bring scattered
convection to at least the northwest half of the CWA starting late
this afternoon. A closed upper low now over WY is progged to track
east and reach the central SD/NE border by late afternoon. A
nocturnal low-level jet over the Central Plains and modest
isentropic ascent are currently aiding a narrow band of elevated
convection from central KS into south central NE. This activity is
expected to lift northeast and possibly graze the northwest tip of
MO this morning before dissipating.
Several additional features will generate strong/severe convection
from western OK through central KS and into far northwest MO. A
dryline will set up from central KS through far western OK this
afternoon while a cold front swings southeast from under the WY
system. As a h7 vorticity max/lobe emerges from under the WY system
and ejects northeast across KS scattered surface-based convection
will form along the KS/OK portion of the dryline. In addition storms
will form over southeast NE/northeast KS where a weak boundary left
by this mornings convection or a pre-frontal convergence zone lies.
The NE/KS convection should affect the northwest 1/3 of the CWA late
this afternoon and early evening. Moderate instability around 1500
J/kg with 30kt 0-6km shear may be sufficient to support a few
marginally severe storms. The primary threat will be large hail. The
severe threat will last several hours ending a few hours after
sunset as the storms weaken as they move east into a less favorable
environment. Coverage and intensity will gradually decrease with
time such that most of the convection will have dissipated by the
pre-dawn hours of Monday morning.
The severe storms which form along the KS/OK dryline may never reach
the CWA as they will weaken and tend to decrease in coverage as they
lift northeast and off the dryline. Accept the model trends in
slowing the arrival of the convection into the CWA as well as
decreasing it in coverage. So, have lowered PoPs for all but the
northwest 1/3 of the CWA as well as limit the QPF.
Monday - Saturday:
As noted in yesterday`s discussion this will be a very active period
with several additional periods of strong/possibly severe convection
as well as the potential for heavy rainfall Tuesday night/Wednesday.
While Monday looks relatively quiet isolated convection is still
possible as the earlier mentioned cold front stalls over the CWA and
around 1000 J/kg of instability will be available. Increasing mid
level heights and the lack of an upper level feature should greatly
limit convection.
By Tuesday the next closed upper system will move out of the Central
High Plains. This system will be much larger with a better defined
negatively tilted shortwave ejecting northeast across KS. With
surface dewpoints likely well into the 60s advecting into the region
there will be ample instability, in excess of 2500 J/kg, to supply
the needed energy for severe convection Tuesday evening. Will need
to keep a close eye on where the warm front will be as it will be a
primary focus for severe storm development. However, the shear will
be near the lower end of the threshold with 0-6km shear in the 25-
30kt range. Heavy rainfall will also be a concern Tuesday
night/Wednesday as precipitable water values between 1.25 and 1.5
inches are near the 99% percentile.
Should see at least a one day break in the rain on Thursday,
possibly carrying over into the first part of Friday before the next
upper trough sends the first wave of warm air advection convection
into the CWA by Friday evening. Timing differences between the ECMWF
and the GFS by the end of the week requires more of a broadbrush
approach on rain chances. Even then PoPs will be rather high this
far out. Should we get as much rain as the models are advertising in
the upcoming week we should eliminate the yearly shortage in
precipitation.
&&
.Aviation...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1046 PM CDT SAT APR 23 2016
VFR conditions expected through much of the fcst period. Latest
model runs suggesting the bulk of thunderstorm activity will remain
west of the forecast area. Cannot rule out some isolated convection
holding itself together as it moves east off the dryline in central
Kansas...but activity will be moving into a more and more unfavorable
environment with further eastward progress. In any event...have
inserted a VCTS mention for STJ...and later updates can address the
KC terminals if trends begin to change. The other main concern
remains the likelihood for LLWS early this morning thanks to a strong
southwesterly low-level jet...and have maintained mention for all
terminals with the 06z package. Meanwhile...southerly winds of 10-15
kts overnight will increase after 16z on Sunday with gusts up to 30
kts possible during the afternoon hours.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...MJ
Aviation...32
[top]
Area Forecast Discussion
National Weather Service Saint Louis MO
355 AM CDT SUN APR 24 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 355 AM CDT Sun Apr 24 2016
The sfc ridge is expected to build further ewd today, allowing sly
winds across the region. An upper ridge is expected to remain in
place today, which will keep precip W of the CWA.
The light FG across ern portions of the CWA shud dissipate by mid-
morning. This area shud also see the most cloud cover, but is still
expected to be only sct coverage. However, high clouds shud cover
the region. Believe these clouds, other than those lower over ern
CWA, will have little impact on temps today. Have trended aoa the
warmer guidance across the region.
Tilly
.LONG TERM... (Tonight through Saturday)
Issued at 355 AM CDT Sun Apr 24 2016
An omega block will dominate Canada and the northern CONUS thru this
week, with upper longwave TROFs on the west and east coasts and the
RIDGE component over the Plains. A series of strong Pacific storms
will run just south of this blocking pattern, being dropped off from
the west coast TROF and being picked up by the east coast TROF a few
days later, with an overall track to the E-NE thru our region. Model
progs show that each successive storm system will track a bit
further south than its predecessor.
The first storm system will track to our north late tonight and into
Monday, and will be just a glancing blow to our region as a result,
with what forms mostly upstream initially to our northwest working
its way in late tonight as it weakens with a possible low level
boundary setting up for additional development further southeast
during the day on Monday.
In the wake of this first storm system, a cold front will drop down
late Monday night into Tuesday and will maintain a low chance for
rain. Severe storm chances up until this point look to be low.
The second Pacific storm system will be more of a direct hit as it
will initially correspond well with the surface frontal boundary
buckling north as a warm front late Tuesday night into Wednesday
morning. This should result in elevated storms, with hail as their
primary severe threat during that time.
Heading into Wednesday afternoon and evening, it will depend heavily
on how far north the front gets. Models continue to skiddishly
track the frontal boundary a tad further south than where they were
progging it 24hrs prior, but the bottom line still remains nearly
the same for now, with a strong shear and unstable environment with
a low level boundary for severe storm formation potential, including
tornadoes.
Things dry out briefly for late in the work week before the third
storm system approaches from the west for the upcoming weekend and
rain chances ramp up again. But with this storm system expected to
track the furthest south, this next episode of rain could very well
be mostly showers with imbedded storms if this track holds, with any
severe potential remaining well to the south.
Otherwise, the default RIDGE setup in our part of the CONUS will
ensure that temps remain at or above average throughout the period.
TES
&&
.AVIATION... (For the 06z TAFs through 06z Sunday Night)
Issued at 1152 PM CDT Sat Apr 23 2016
Dry and VFR conditions are still expected at the terminals through
the TAF period. There may be some patchy fog late tonight and
early Sunday over southern Illinois and southeast Missouri. Low
level wind shear is still possible at KUIN and KCOU between 09-15Z
as a 35-40kt low level jet sets up between 1000-2000 feet. Still
expect gusts over 20kts during the late morning and afternoon
hours that will decrease slightly after sunset.
Specifics for KSTL:
Dry and VFR conditions are expected through the TAF period. Gusts
above 20 kts are possible after 18Z on Sunday afternoon.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
[top]
Area Forecast Discussion
National Weather Service Springfield MO
347 AM CDT SUN APR 24 2016
.SHORT TERM...(Today and tonight)
Issued at 343 AM CDT Sun Apr 24 2016
An upper level ridge remains over the central U.S. early this
morning along with a warm air mass. Early morning temperatures are
currently in the upper 50s to lower 60s. Temperatures will not
drop much more early this morning with lows in the middle 50s to
around 60 occurring.
An upper level low is currently over Wyoming early this morning,
and will track to the east and opening up today into tonight. This
will start to push the ridge to the east today. Surface low
pressure has developed ahead of the upper level low across the
plains. The pressure gradient will tighten across the region today
as the low tracks east. Temperatures will be very similar to those
that were observed on Saturday with highs in the upper 70s to the
lower 80s. There will be few more clouds today than yesterday but
still plenty of sunshine will occur. Southerly winds will increase
and be gusty today ahead of the approaching system and gusts over
30 mph will occur at times mainly along and west of Hwy 65 this
afternoon.
A cold front associated with the surface low will track east
across portions of central and eastern Nebraska and Kansas today
into tonight. This evening Thunderstorms will develop along the
front to the west and northwest of the forecast area. The front
will remain to the west and north of the area and not move into
the area overnight. Storms will likely move off the front but
instability will be weaker the farther to the east and with the
better lift remaining west of the area storms will weaken as they
push into the area. A few storms may make it into the area before
dissipating but most locations should remain dry.
.LONG TERM...(Monday through Saturday)
Issued at 343 AM CDT Sun Apr 24 2016
The front is expected to remain north of the area on Monday as the
upper level trough and surface low push off to the east. Shortwave
upper level ridging will build over the area on Monday. Can not
rule out an isolated shower/rumble of thunder mainly in the
morning hours as isentropic lift spreads across the area ahead of
the ridge, but expect most location to remain dry during the day
on Monday.
Isentropic lift will again develop, mainly over the extreme
southeastern Kansas and far southwestern Missouri Monday night
into Tuesday morning. Instability will start to develop across
the area as Gulf moisture spread north, but a cap will also develop
across the area. The cap does weaken some for an elevated storm,
but it does not go completely away. Did include a chance for
thunderstorms to develop across the western portions of the
forecast area to account for this. Instability for an elevated
storm will be limited so not expecting strong to severe storms at
this time.
An upper level trough will lift across the plains on Tuesday then
to the north of the area on Wednesday. Instability will increase
across the region ahead of this system but so will the cap. So,
besides a few morning storms mentioned above, think the cap will
keep much of the afternoon hours dry. Surface low pressure will
develop across the central Plains and connect with the front that
will stall to the north of the area, with it being a warm front.
As the Low level jet increases Tuesday evening storms are expected
to develop along and just north of the warm front, at this time
the front is expected to remain north of the area and these storms
should too.
As the low lifts to the northeast a cold front will move east
across central Kansas and central Oklahoma late Tuesday afternoon
into Tuesday evening. The cap will weaken enough for storms to
develop along and ahead of the front. They should be able to move
off the front as the front only slowly moves east, resulting in
the potential for supercells. The front will not push east into
the area Tuesday night, but cold pools from the storms could
congeal and keep the storms going to the east, in more of a line
or line segments, pushing into and across the area Tuesday night
into Wednesday morning. Instability will be weaker given the
overnight timing, but will remain strong enough to support a
severe risk across the area Tuesday night and Wednesday. Low level
shear will increase with the approach of the storm system, so all
modes of severe weather will be possible, through large hail and
damaging straight line winds will be the main risk. The front will
push across the region Wednesday with the storms/rain chances
ending Wednesday evening.
Thursday will be a dry day then yet another storm system will
track into and across the region Friday into the weekend bringing
additional rounds for showers and thunderstorms to the region.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1144 PM CDT Sat Apr 23 2016
For the KSGF/KJLN/KBBG tafs: VFR conditions are expected with
increasing south to southeast winds. Low pressure will move into
the Plains with an increasing pressure gradient and sfc winds by
15z. High resolution models support sustained 15-20kt winds with
higher gusts.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...DSA
Area Forecast Discussion
National Weather Service Springfield MO
1158 PM CDT SAT APR 23 2016
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1144 PM CDT Sat Apr 23 2016
For the KSGF/KJLN/KBBG tafs: VFR conditions are expected with
increasing south to southeast winds. Low pressure will move into
the Plains with an increasing pressure gradient and sfc winds by
15z. High resolution models support sustained 15-20kt winds with
higher gusts.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...DSA
Area Forecast Discussion
National Weather Service Springfield MO
1158 PM CDT SAT APR 23 2016
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1144 PM CDT Sat Apr 23 2016
For the KSGF/KJLN/KBBG tafs: VFR conditions are expected with
increasing south to southeast winds. Low pressure will move into
the Plains with an increasing pressure gradient and sfc winds by
15z. High resolution models support sustained 15-20kt winds with
higher gusts.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...DSA
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1152 PM CDT SAT APR 23 2016
.UPDATE...
Issued at 921 PM CDT Sat Apr 23 2016
Going dry forecast the rest of the night still looks good as upper
ridge moves over the area allowing for only a few high clouds to
drift across the area. Still may be some patchy fog tonight, but
think this will be held in check by the wind which should stay up
tonight as the pressure gradient continues to tighten. Only made
minor adjustments to lows based on going temperature trends.
Britt
&&
.SHORT TERM... (Through Late Tonight)
Issued at 255 PM CDT Sat Apr 23 2016
Surface ridge extending from MI southwest into eastern MO will move
eastward. The stratus clouds across southeast IL should continue to
dissipate late this afternoon. Few-scattered diurnal cumulus
clouds, especially across parts of northeast and central MO will
dissipate early this evening with the loss of daytime heating.
Mainly just a little high level cloudiness tonight. Lows tonight
will be warmer than the previous night, mainly due to southeast
surface winds on the backside of the surface ridge. The warmest
temperatures will be across central MO with the coolest temperatures
in southwest IL. Lows tonight will be about 5 to 10 degrees above
normal for late April.
GKS
.LONG TERM... (Sunday through Next Saturday)
Issued at 255 PM CDT Sat Apr 23 2016
Dry and warmer weather to persist on Sunday, but will see an
increase in high clouds as next weather system approaches region.
With gusty south winds will see highs in the upper 70s to low 80s.
Sunday night rain chances to approach region, but models are a bit
slower with onset, so lowered pops just a bit. Then Monday through
Tuesday, frontal boundary to slowly slide south through area with
mainly scattered showers and thunderstorms. Front to stall out
across southern Missouri on Tuesday. Highs will be in the upper 70s
to low 80s on Monday, then dip down into the low 70s to low 80s
Tuesday and Wednesday.
Decent instability north of front Tuesday night, so could see
elevated activity develop and slide along boundary on nose of decent
low level jet. Large hail would be the main threat with this round
of storms.
Models are still indicating decent instability, CAPES in excess of
1500 J/kg and shear with system Wednesday afternoon, Wednesday night
as warm front lifts north through forecast area. All of this still
points to our first real potential severe weather day this spring,
but a lot can happen in 5 days. Stay tuned to further updates.
With everything a bit slower, main cold front to slide through early
on Thursday with precipitation tapering off to just slight chance
pops through Friday. Then extended models showing next system
lifting northeast towards forecast area Friday night and Saturday
with increasing chances of showers and thunderstorms once again.
Once system exits region on Thursday, will see precipitation taper
off. Even though it will be a bit cooler Thursday, highs will still
be a bit above normal in the mid 60s to upper 70s. Extended models
beginning to indicate another system approaching region on Friday,
but timing is hard to pin down. So for now kept slight chance pops.
Byrd
&&
.AVIATION... (For the 06z TAFs through 06z Sunday Night)
Issued at 1152 PM CDT Sat Apr 23 2016
Dry and VFR conditions are still expected at the terminals through
the TAF period. There may be some patchy fog late tonight and
early Sunday over southern Illinois and southeast Missouri. Low
level wind shear is still possible at KUIN and KCOU between 09-15Z
as a 35-40kt low level jet sets up between 1000-2000 feet. Still
expect gusts over 20kts during the late morning and afternoon
hours that will decrease slightly after sunset.
Specifics for KSTL:
Dry and VFR conditions are expected through the TAF period. Gusts
above 20 kts are possible after 18Z on Sunday afternoon.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1047 PM CDT SAT APR 23 2016
.Short Term...(This Evening through Monday Night)
Issued at 309 PM CDT SAT APR 23 2016
Short Term (Tonight through Monday night):
The main concern in the short term will be the potential for a few
strong and isolated severe storms on Sunday evening into Sunday
night. Tonight, however will be much less interesting and quite
pleasant as modest southerly winds will hold temperatures in the mid
50s to lower 60s. The system, an upper level trough, that will bring
thunderstorms to the area Sunday will move from western Wyoming to
near the WY/SD/NE by Saturday night. This will force a cold front into
the western Plains. Thunderstorms will develop along this front
tonight across western Kansas. This storms will progress across
Kansas overnight enhanced by a 50-60kt SSWly nocturnal LLJ. By early
Sunday morning the LLJ will veer to the southwest and storms will
begin to approach northeastern KS and northwestern MO. However,
these storms will be weakening as they approach and there may just
be a few isolated storms or residual shower to make it into the
extreme NW CWA Sunday morning. However, by Sunday afternoon, a dry
line will exist across central Kansas with the attendant cold front
lagging to the west across the western High Plains. Thunderstorms
are expected to develop out ahead of the cold front across central
Kansas during the afternoon and move eastward. These storms will
have the potential to be strong with perhaps isolated severe storms
possible mainly across northwestern MO/northeastern KS where
dewpoints will be near 60 degrees, modest instability of 500-
800J/kg, and steep mid-level lapse rates will exist. However, shear
is not impressive and as previously mentioned instability is merely
modest. Consequently, strong storms will be possible and perhaps
even a marginally severe storm capable of producing large hail or
damaging winds. Storms will weaken Sunday night as storms move into
a more stable environment and the upper level trough continues to
weak as it moves into the Upper Midwest. On Monday, the cold front
associated with the upper level system will sag through the area.
However, will little forcing the front will sag through the area
with little activity expected. The best chance for storms would
occur head of the front where modest instability will reside. Monday
night the cold front will sink south of the area and become
stationary. A few thunderstorms may develop north of the stationary
boundary Monday as a SW 40kt LLJ overrides the boundary. These
thunderstorms may affect the southern CWA depending on the location
of the front.
.Long Term...(Tuesday through Saturday)
Issued at 309 PM CDT SAT APR 23 2016
Tuesday evening and Wednesday will bring another round of showers
and possibly severe thunderstorms to the CWA. The most recent NAM
and GFS runs show Tuesday morning and early afternoon warm and humid
with precipitation mainly staying just south of the WFO. A negatively
tilted low pressure trough stations itself over eastern CO/western KS
Tuesday afternoon. A cold front will move east through Kansas
Wednesday afternoon, and an associated warm front will be located E-W
through our forecast area late Tuesday bringing low- level moisture
with it. Dew point temperatures will range from low 50s north of the
front spreading south to the mid-60s. We will also have decent
instability and shear with CAPE values around 1000-2000 J/kg and
30-50 kt 0-6 km bulk shear. A combination of high CAPE and shear may
lead to potentially severe thunderstorms ahead of the cold front. The
development and location of severe weather will depend on the timing
of convection and the frontal passage, which will become more clear
as we get closer to the event. For now, the GFS and Euro models show
precipitation starting in eastern KS and moving east through the WFO
late Tuesday night through Wednesday morning. Convection could
continue throughout Wednesday as CAPE values are expected to stay
above 1000 J/kg throughout Wednesday afternoon.
High temperatures will continue to be in the mid 70s through
Wednesday, but will drop to the mid-high 60s for Thursday and Friday
after the cold front passes. Low temperatures will drop Thursday and
Friday mornings to the high 40s to low 50s. Thursday is expected to
be dry before another upper low system may cause more precipitation
late Friday into Saturday.
&&
.Aviation...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1046 PM CDT SAT APR 23 2016
VFR conditions expected through much of the fcst period. Latest
model runs suggesting the bulk of thunderstorm activity will remain
west of the forecast area. Cannot rule out some isolated convection
holding itself together as it moves east off the dryline in central
Kansas...but activity will be moving into a more and more unfavorable
environment with further eastward progress. In any event...have
inserted a VCTS mention for STJ...and later updates can address the
KC terminals if trends begin to change. The other main concern
remains the likelihood for LLWS early this morning thanks to a strong
southwesterly low-level jet...and have maintained mention for all
terminals with the 06z package. Meanwhile...southerly winds of 10-15
kts overnight will increase after 16z on Sunday with gusts up to 30
kts possible during the afternoon hours.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Short Term...73
Long Term...Chandler/CDB
Aviation...32
Area Forecast Discussion...Updated
National Weather Service Saint Louis MO
921 PM CDT SAT APR 23 2016
.UPDATE...
Issued at 921 PM CDT Sat Apr 23 2016
Going dry forecast the rest of the night still looks good as upper
ridge moves over the area allowing for only a few high clouds to
drift across the area. Still may be some patchy fog tonight, but
think this will be held in check by the wind which should stay up
tonight as the pressure gradient continues to tighten. Only made
minor adjustments to lows based on going temperature trends.
Britt
&&
.SHORT TERM... (Through Late Tonight)
Issued at 255 PM CDT Sat Apr 23 2016
Surface ridge extending from MI southwest into eastern MO will move
eastward. The stratus clouds across southeast IL should continue to
dissipate late this afternoon. Few-scattered diurnal cumulus
clouds, especially across parts of northeast and central MO will
dissipate early this evening with the loss of daytime heating.
Mainly just a little high level cloudiness tonight. Lows tonight
will be warmer than the previous night, mainly due to southeast
surface winds on the backside of the surface ridge. The warmest
temperatures will be across central MO with the coolest temperatures
in southwest IL. Lows tonight will be about 5 to 10 degrees above
normal for late April.
GKS
.LONG TERM... (Sunday through Next Saturday)
Issued at 255 PM CDT Sat Apr 23 2016
Dry and warmer weather to persist on Sunday, but will see an
increase in high clouds as next weather system approaches region.
With gusty south winds will see highs in the upper 70s to low 80s.
Sunday night rain chances to approach region, but models are a bit
slower with onset, so lowered pops just a bit. Then Monday through
Tuesday, frontal boundary to slowly slide south through area with
mainly scattered showers and thunderstorms. Front to stall out
across southern Missouri on Tuesday. Highs will be in the upper 70s
to low 80s on Monday, then dip down into the low 70s to low 80s
Tuesday and Wednesday.
Decent instability north of front Tuesday night, so could see
elevated activity develop and slide along boundary on nose of decent
low level jet. Large hail would be the main threat with this round
of storms.
Models are still indicating decent instability, CAPES in excess of
1500 J/kg and shear with system Wednesday afternoon, Wednesday night
as warm front lifts north through forecast area. All of this still
points to our first real potential severe weather day this spring,
but a lot can happen in 5 days. Stay tuned to further updates.
With everything a bit slower, main cold front to slide through early
on Thursday with precipitation tapering off to just slight chance
pops through Friday. Then extended models showing next system
lifting northeast towards forecast area Friday night and Saturday
with increasing chances of showers and thunderstorms once again.
Once system exits region on Thursday, will see precipitation taper
off. Even though it will be a bit cooler Thursday, highs will still
be a bit above normal in the mid 60s to upper 70s. Extended models
beginning to indicate another system approaching region on Friday,
but timing is hard to pin down. So for now kept slight chance pops.
Byrd
&&
.AVIATION... (For the 00z TAFs through 00z Sunday Evening)
Issued at 650 PM CDT Sat Apr 23 2016
Dry and VFR conditions are expected at the terminals. There may be
some patchy fog late tonight and early Sunday over southern
Illinois and southeast Missouri. Low level wind shear is still
possible at KUIN and KCOU between 09-15Z as a 35-40kt low level
jet sets up between 1000-2000 feet. This threat will end by mid
morning as mixing begins and the surface winds begin to pick up.
Do expect some gusts above 20kts during the late morning and
afternoon hours.
Specifics for KSTL: Dry and VFR conditions are expected the next
30 hours. Southerly winds will increase after 18Z on Sunday
afternoon with wind gusts over 20kts.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
705 PM CDT SAT APR 23 2016
.SHORT TERM... (Through Late Tonight)
Issued at 255 PM CDT Sat Apr 23 2016
Surface ridge extending from MI southwest into eastern MO will move
eastward. The stratus clouds across southeast IL should continue to
dissipate late this afternoon. Few-scattered diurnal cumulus
clouds, especially across parts of northeast and central MO will
dissipate early this evening with the loss of daytime heating.
Mainly just a little high level cloudiness tonight. Lows tonight
will be warmer than the previous night, mainly due to southeast
surface winds on the backside of the surface ridge. The warmest
temperatures will be across central MO with the coolest temperatures
in southwest IL. Lows tonight will be about 5 to 10 degrees above
normal for late April.
GKS
.LONG TERM... (Sunday through Next Saturday)
Issued at 255 PM CDT Sat Apr 23 2016
Dry and warmer weather to persist on Sunday, but will see an
increase in high clouds as next weather system approaches region.
With gusty south winds will see highs in the upper 70s to low 80s.
Sunday night rain chances to approach region, but models are a bit
slower with onset, so lowered pops just a bit. Then Monday through
Tuesday, frontal boundary to slowly slide south through area with
mainly scattered showers and thunderstorms. Front to stall out
across southern Missouri on Tuesday. Highs will be in the upper 70s
to low 80s on Monday, then dip down into the low 70s to low 80s
Tuesday and Wednesday.
Decent instability north of front Tuesday night, so could see
elevated activity develop and slide along boundary on nose of decent
low level jet. Large hail would be the main threat with this round
of storms.
Models are still indicating decent instability, CAPES in excess of
1500 J/kg and shear with system Wednesday afternoon, Wednesday night
as warm front lifts north through forecast area. All of this still
points to our first real potential severe weather day this spring,
but a lot can happen in 5 days. Stay tuned to further updates.
With everything a bit slower, main cold front to slide through early
on Thursday with precipitation tapering off to just slight chance
pops through Friday. Then extended models showing next system
lifting northeast towards forecast area Friday night and Saturday
with increasing chances of showers and thunderstorms once again.
Once system exits region on Thursday, will see precipitation taper
off. Even though it will be a bit cooler Thursday, highs will still
be a bit above normal in the mid 60s to upper 70s. Extended models
beginning to indicate another system approaching region on Friday,
but timing is hard to pin down. So for now kept slight chance pops.
Byrd
&&
.AVIATION... (For the 00z TAFs through 00z Sunday Evening)
Issued at 650 PM CDT Sat Apr 23 2016
Dry and VFR conditions are expected at the terminals. There may be
some patchy fog late tonight and early Sunday over southern
Illinois and southeast Missouri. Low level wind shear is still
possible at KUIN and KCOU between 09-15Z as a 35-40kt low level
jet sets up between 1000-2000 feet. This threat will end by mid
morning as mixing begins and the surface winds begin to pick up.
Do expect some gusts above 20kts during the late morning and
afternoon hours.
Specifics for KSTL: Dry and VFR conditions are expected the next
30 hours. Southerly winds will increase after 18Z on Sunday
afternoon with wind gusts over 20kts.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
629 PM CDT SAT APR 23 2016
.Short Term...(This Evening through Monday Night)
Issued at 309 PM CDT SAT APR 23 2016
Short Term (Tonight through Monday night):
The main concern in the short term will be the potential for a few
strong and isolated severe storms on Sunday evening into Sunday
night. Tonight, however will be much less interesting and quite
pleasant as modest southerly winds will hold temperatures in the mid
50s to lower 60s. The system, an upper level trough, that will bring
thunderstorms to the area Sunday will move from western Wyoming to
near the WY/SD/NE by Saturday night. This will force a cold front into
the western Plains. Thunderstorms will develop along this front
tonight across western Kansas. This storms will progress across
Kansas overnight enhanced by a 50-60kt SSWly nocturnal LLJ. By early
Sunday morning the LLJ will veer to the southwest and storms will
begin to approach northeastern KS and northwestern MO. However,
these storms will be weakening as they approach and there may just
be a few isolated storms or residual shower to make it into the
extreme NW CWA Sunday morning. However, by Sunday afternoon, a dry
line will exist across central Kansas with the attendant cold front
lagging to the west across the western High Plains. Thunderstorms
are expected to develop out ahead of the cold front across central
Kansas during the afternoon and move eastward. These storms will
have the potential to be strong with perhaps isolated severe storms
possible mainly across northwestern MO/northeastern KS where
dewpoints will be near 60 degrees, modest instability of 500-
800J/kg, and steep mid-level lapse rates will exist. However, shear
is not impressive and as previously mentioned instability is merely
modest. Consequently, strong storms will be possible and perhaps
even a marginally severe storm capable of producing large hail or
damaging winds. Storms will weaken Sunday night as storms move into
a more stable environment and the upper level trough continues to
weak as it moves into the Upper Midwest. On Monday, the cold front
associated with the upper level system will sag through the area.
However, will little forcing the front will sag through the area
with little activity expected. The best chance for storms would
occur head of the front where modest instability will reside. Monday
night the cold front will sink south of the area and become
stationary. A few thunderstorms may develop north of the stationary
boundary Monday as a SW 40kt LLJ overrides the boundary. These
thunderstorms may affect the southern CWA depending on the location
of the front.
.Long Term...(Tuesday through Saturday)
Issued at 309 PM CDT SAT APR 23 2016
Tuesday evening and Wednesday will bring another round of showers
and possibly severe thunderstorms to the CWA. The most recent NAM
and GFS runs show Tuesday morning and early afternoon warm and humid
with precipitation mainly staying just south of the WFO. A negatively
tilted low pressure trough stations itself over eastern CO/western KS
Tuesday afternoon. A cold front will move east through Kansas
Wednesday afternoon, and an associated warm front will be located E-W
through our forecast area late Tuesday bringing low- level moisture
with it. Dew point temperatures will range from low 50s north of the
front spreading south to the mid-60s. We will also have decent
instability and shear with CAPE values around 1000-2000 J/kg and
30-50 kt 0-6 km bulk shear. A combination of high CAPE and shear may
lead to potentially severe thunderstorms ahead of the cold front. The
development and location of severe weather will depend on the timing
of convection and the frontal passage, which will become more clear
as we get closer to the event. For now, the GFS and Euro models show
precipitation starting in eastern KS and moving east through the WFO
late Tuesday night through Wednesday morning. Convection could
continue throughout Wednesday as CAPE values are expected to stay
above 1000 J/kg throughout Wednesday afternoon.
High temperatures will continue to be in the mid 70s through
Wednesday, but will drop to the mid-high 60s for Thursday and Friday
after the cold front passes. Low temperatures will drop Thursday and
Friday mornings to the high 40s to low 50s. Thursday is expected to
be dry before another upper low system may cause more precipitation
late Friday into Saturday.
&&
.Aviation...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 629 PM CDT SAT APR 23 2016
VFR conditions anticipated through the fcst period with modest south
winds of 10-15 kts expected through the overnight before increasing
after 16z. Further aloft...a strong southwesterly low-level jet of
roughly 45 kts will lead to increasing LLWS concerns after 06z and a
mention has been added for all forecast locations. Precip chances in
the form of shwrs/storms look to increase after 21z...however the
mostly likely location right now appears to be STJ based on expected
dryline configuration. Will consider adding further south with the
next forecast issuance.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Short Term...73
Long Term...Chandler/CDB
Aviation...32
Area Forecast Discussion
National Weather Service Springfield MO
616 PM CDT SAT APR 23 2016
...00z Aviation Update...
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 616 PM CDT Sat Apr 23 2016
VFR conditions will again persist through this TAF cycle. Winds
have become southerly (as advertised) during the day today.
Surface winds will steadily increase through Sunday ahead of a
passing system over the plains. Gusty southerly winds can be
expected for SGF and JLN by Sunday afternoon and should continue
through the end of the period.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Frye
Area Forecast Discussion
National Weather Service Springfield MO
616 PM CDT SAT APR 23 2016
...00z Aviation Update...
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 616 PM CDT Sat Apr 23 2016
VFR conditions will again persist through this TAF cycle. Winds
have become southerly (as advertised) during the day today.
Surface winds will steadily increase through Sunday ahead of a
passing system over the plains. Gusty southerly winds can be
expected for SGF and JLN by Sunday afternoon and should continue
through the end of the period.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Frye
Area Forecast Discussion
National Weather Service Springfield MO
328 PM CDT SAT APR 23 2016
...Beautiful Weather This Weekend...Increasing Confidence for
Strong to Severe Storms Next Week...
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1159 AM CDT Sat Apr 23 2016
VFR conditions are expected through the period as surface high
pressure continues to drift eastward and an upper level ridge
moves across the area. Main forecast concern is gusty winds
beginning after sunrise on Sunday as the next approaching system
begins to tighten up the surface pressure gradient. Winds should
develop gusts after 13z at KSGF/KJLN but believe that it will be
later in the afternoon...after the end of the forecast
period...for KBBG.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Gaede
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
310 PM CDT SAT APR 23 2016
.Short Term...(This Evening through Monday Night)
Issued at 309 PM CDT SAT APR 23 2016
Short Term (Tonight through Monday night):
The main concern in the short term will be the potential for a few
strong and isolated severe storms on Sunday evening into Sunday
night. Tonight, however will be much less interesting and quite
pleasant as modest southerly winds will hold temperatures in the mid
50s to lower 60s. The system, an upper level trough, that will bring
thunderstorms to the area Sunday will move from western Wyoming to
near the WY/SD/NE by Saturday night. This will force a cold front into
the western Plains. Thunderstorms will develop along this front
tonight across western Kansas. This storms will progress across
Kansas overnight enhanced by a 50-60kt SSWly nocturnal LLJ. By early
Sunday morning the LLJ will veer to the southwest and storms will
begin to approach northeastern KS and northwestern MO. However,
these storms will be weakening as they approach and there may just
be a few isolated storms or residual shower to make it into the
extreme NW CWA Sunday morning. However, by Sunday afternoon, a dry
line will exist across central Kansas with the attendant cold front
lagging to the west across the western High Plains. Thunderstorms
are expected to develop out ahead of the cold front across central
Kansas during the afternoon and move eastward. These storms will
have the potential to be strong with perhaps isolated severe storms
possible mainly across northwestern MO/northeastern KS where
dewpoints will be near 60 degrees, modest instability of 500-
800J/kg, and steep mid-level lapse rates will exist. However, shear
is not impressive and as previously mentioned instability is merely
modest. Consequently, strong storms will be possible and perhaps
even a marginally severe storm capable of producing large hail or
damaging winds. Storms will weaken Sunday night as storms move into
a more stable environment and the upper level trough continues to
weak as it moves into the Upper Midwest. On Monday, the cold front
associated with the upper level system will sag through the area.
However, will little forcing the front will sag through the area
with little activity expected. The best chance for storms would
occur head of the front where modest instability will reside. Monday
night the cold front will sink south of the area and become
stationary. A few thunderstorms may develop north of the stationary
boundary Monday as a SW 40kt LLJ overrides the boundary. These
thunderstorms may affect the southern CWA depending on the location
of the front.
.Long Term...(Tuesday through Saturday)
Issued at 309 PM CDT SAT APR 23 2016
Tuesday evening and Wednesday will bring another round of showers
and possibly severe thunderstorms to the CWA. The most recent NAM
and GFS runs show Tuesday morning and early afternoon warm and humid
with precipitation mainly staying just south of the WFO. A negatively
tilted low pressure trough stations itself over eastern CO/western KS
Tuesday afternoon. A cold front will move east through Kansas
Wednesday afternoon, and an associated warm front will be located E-W
through our forecast area late Tuesday bringing low- level moisture
with it. Dew point temperatures will range from low 50s north of the
front spreading south to the mid-60s. We will also have decent
instability and shear with CAPE values around 1000-2000 J/kg and
30-50 kt 0-6 km bulk shear. A combination of high CAPE and shear may
lead to potentially severe thunderstorms ahead of the cold front. The
development and location of severe weather will depend on the timing
of convection and the frontal passage, which will become more clear
as we get closer to the event. For now, the GFS and Euro models show
precipitation starting in eastern KS and moving east through the WFO
late Tuesday night through Wednesday morning. Convection could
continue throughout Wednesday as CAPE values are expected to stay
above 1000 J/kg throughout Wednesday afternoon.
High temperatures will continue to be in the mid 70s through
Wednesday, but will drop to the mid-high 60s for Thursday and Friday
after the cold front passes. Low temperatures will drop Thursday and
Friday mornings to the high 40s to low 50s. Thursday is expected to
be dry before another upper low system may cause more precipitation
late Friday into Saturday.
&&
.Aviation...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1230 PM CDT SAT APR 23 2016
VFR conds will prevail through the pd with mainly just sct high
clouds expected. Winds will pick up out of the south this afternoon
to 10-15kts with gusts to around 20kts. Winds will lose their gusts
this evening but still remain around 10-15kts. However, tomorrow
morning winds will again increase to 15-20kts with gusts to 25-30kts.
LLWS may be a marginal concern tonight as winds at 2kft will be out
of the SSW at 35-40kts btn 06Z-14Z and, may need to be added to the
TAF at the 00Z issuance.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Short Term...73
Long Term...Chandler/CDB
Aviation...73
Area Forecast Discussion
National Weather Service Saint Louis MO
257 PM CDT SAT APR 23 2016
.SHORT TERM... (Through Late Tonight)
Issued at 255 PM CDT Sat Apr 23 2016
Surface ridge extending from MI southwest into eastern MO will move
eastward. The stratus clouds across southeast IL should continue to
dissipate late this afternoon. Few-scattered diurnal cumulus
clouds, especially across parts of northeast and central MO will
dissipate early this evening with the loss of daytime heating.
Mainly just a little high level cloudiness tonight. Lows tonight
will be warmer than the previous night, mainly due to southeast
surface winds on the backside of the surface ridge. The warmest
temperatures will be across central MO with the coolest temperatures
in southwest IL. Lows tonight will be about 5 to 10 degrees above
normal for late April.
GKS
.LONG TERM... (Sunday through Next Saturday)
Issued at 255 PM CDT Sat Apr 23 2016
Dry and warmer weather to persist on Sunday, but will see an
increase in high clouds as next weather system approaches region.
With gusty south winds will see highs in the upper 70s to low 80s.
Sunday night rain chances to approach region, but models are a bit
slower with onset, so lowered pops just a bit. Then Monday through
Tuesday, frontal boundary to slowly slide south through area with
mainly scattered showers and thunderstorms. Front to stall out
across southern Missouri on Tuesday. Highs will be in the upper 70s
to low 80s on Monday, then dip down into the low 70s to low 80s
Tuesday and Wednesday.
Decent instability north of front Tuesday night, so could see
elevated activity develop and slide along boundary on nose of decent
low level jet. Large hail would be the main threat with this round
of storms.
Models are still indicating decent instability, CAPES in excess of
1500 J/kg and shear with system Wednesday afternoon, Wednesday night
as warm front lifts north through forecast area. All of this still
points to our first real potential severe weather day this spring,
but a lot can happen in 5 days. Stay tuned to further updates.
With everything a bit slower, main cold front to slide through early
on Thursday with precipitation tapering off to just slight chance
pops through Friday. Then extended models showing next system
lifting northeast towards forecast area Friday night and Saturday
with increasing chances of showers and thunderstorms once again.
Once system exits region on Thursday, will see precipitation taper
off. Even though it will be a bit cooler Thursday, highs will still
be a bit above normal in the mid 60s to upper 70s. Extended models
beginning to indicate another system approaching region on Friday,
but timing is hard to pin down. So for now kept slight chance pops.
Byrd
&&
.AVIATION... (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1104 AM CDT Sat Apr 23 2016
Surface ridge extending from the Great Lakes region southwest
into eastern MO will shift eastward this period. The low level
cloudiness over eastern IA into northeast MO should remain north
of UIN this afternoon. The stratus cloudiness across southeast IL
should gradually dissipate this afternoon with daytime heating,
mixing and drying and remain east of the St Louis metro area.
There may be a few diurnal cumulus clouds at the taf sites this
afternoon. There will be a little high level cloudiness late
tonight and Sunday morning. Southeasterly surface winds should
strengthen at UIN and COU through the forecast period as the
surface pressure gradient gradually tightens, becoming more
southerly on Sunday. Light northeast wind in the St Louis metro
area will also strengthen as well through the period, veering
around to a southeast direction by early this evening, then
southerly Sunday morning. There will be some LLWS conditions in
UIN and COU very late tonight and early Sunday morning as a
southwesterly low level jet translates eastward into northwest MO
with both speed and directional shear in the lowest 1000 feet.
Specifics for KSTL: Stratus clouds across southeast IL should
gradually dissipate this afternoon and remain east-southeast of
STL. Few diurnal cumulus clouds may develop this afternoon due to
daytime heating, then dissipate early this evening. There will be
some high level cloudiness late tonight and Sunday. Light
northeast wind will increase in speed to 8-10 kts by late this
afternoon or early this evening as it veers around to a southeast
direction. The surface wind will become southerly Sunday morning
and possibly gusty Sunday afternoon.
GKS
&&
.PRELIMINARY POINT TEMPS/POPS...
Saint Louis 55 82 63 81 / 0 0 20 30
Quincy 56 81 61 79 / 5 5 30 30
Columbia 57 81 60 78 / 5 5 20 30
Jefferson City 58 82 61 80 / 5 5 20 30
Salem 51 79 60 80 / 0 0 10 20
Farmington 52 79 60 79 / 0 0 10 20
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1230 PM CDT SAT APR 23 2016
.Discussion...
Issued at 412 AM CDT SAT APR 23 2016
Today - Tonight:
In the very near term will be dealing with patchy dense fog over the
northeast 1/2 of the CWA. The fog and stratus is forming under a
surface ridge with river valleys and low lying areas the most
susceptible. The latest NAM/RAP 925mb condensation pressure deficit
prog best depict the low clouds with the SREF favoring more
widespread dense fog further north in IA.
Otherwise, for today expect a nice warm up as pressure falls over
the Central Plains induce increasing southerly winds. Should see
decent mixing with a dry adiabatic lapse rate yielding highs around
10 degrees above average. Upper level ridging spreading east into
the CWA will provide for continued dry conditions.
Increasing warm air advection aloft will ensue across KS and NE this
evening with scattered elevated convection possibly grazing far
northwest MO towards sunrise Sunday morning. Any convection which
reaches this region should fall apart Sunday morning with convective
debris and mid level accas likely lingering over the western CWA
into the afternoon.
Sunday - Sunday night:
The weather will become more interesting late Sunday afternoon into
the evening as an upper level closed low migrates into SD/NE. A
negatively tilted shortwave trough is progged to rotate from under
the upper low and lift northeast across KS and NE during the
afternoon. A moderately strong low level jet around 45kts will pull
deeper low level moisture ahead of a north-south dryline which will
anchor over central KS and far western OK. Expect to see scattered
strong/severe convection form along the dryline by mid/late
afternoon and track quickly northeast. Far northwest MO stands the
best chance of seeing active convection. Surface based CAPEs around
1500 J/kg and 0-6km shear around 40kts will support
strong/marginally severe storms over this area. All models strongly
suggest the dryline will move little to the east so the severe
threat in the CWA will likely be limited to far northwest MO.
Convection will weaken and decrease in coverage as it moves east
through the CWA with the far southeastern counties receiving the
least QPF.
Monday - Friday:
A fairly active period with two more closed upper lows likely
affecting the region. While Monday initially looked relatively quiet
as the Upper MS Valley system pulls away there is some concern that
some afternoon convection could form along the remnants of a stalled
surface boundary. The limiting factor will be increasing mid level
heights and a lack of upper support. Nonetheless with a front in the
CWA will need to be vigilant.
As we`ve been discussing over the past few days a second and
stronger upper system will become a factor and play a significant
role in our weather by Tuesday night and continuing into Wednesday.
Medium range operational models continue to eject a negatively
tilted shortwave through KS and MO. There is every reason to believe
a west-east frontal boundary will be in the vicinity with this
feature lifting north and through the CWA. Low-level moisture will
not be a problem with low/mid 60 dewpoints likely south of the front
and spreading northward. The GFS indicates 2000-3000 J/kg of CAPE
could be available with 30-40kt 0-6km shear so severe storms are a
growing concern. As always timing of the front and convective
development will determine where severe will occur but our CWA is
currently within the window of opportunity.
Convection could linger well into Wednesday as the upper low opens
up and lifts through NE/KS/IA/MO.
Thursday looks quiet as we`ll be between systems. The third system
we`ll be keeping an eye on will be yet another closed upper low.
This feature may not be a factor until late Friday.
Through out this period expect to see above average temperatures with
an overall increase in humidity.
&&
.Aviation...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1230 PM CDT SAT APR 23 2016
VFR conds will prevail through the pd with mainly just sct high
clouds expected. Winds will pick up out of the south this afternoon
to 10-15kts with gusts to around 20kts. Winds will lose their gusts
this evening but still remain around 10-15kts. However, tomorrow
morning winds will again increase to 15-20kts with gusts to 25-30kts.
LLWS may be a marginal concern tonight as winds at 2kft will be out
of the SSW at 35-40kts btn 06Z-14Z and, may need to be added to the
TAF at the 00Z issuance.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...MJ
Aviation...73
Area Forecast Discussion
National Weather Service Springfield MO
1206 PM CDT SAT APR 23 2016
.SHORT TERM...(Today through Sunday)
Issued at 330 AM CDT Sat Apr 23 2016
An upper level ridge is currently building over the region early
this morning and will be centered over the area by tonight. As an
upper level trough tracks east into the northern Plains on Sunday
the ridge will start to spread off Sunday night.
Warm and dry conditions will occur through much of this weekend
as highs warm into the upper 70s to the lower 80s both afternoons.
Sunny skies will occur today with partly cloudy skies occurring on
Sunday. Gusty southerly winds will develop Sunday afternoon as
surface low pressure develops across the central Plains ahead of
the upper level low. Wind gusts over 30 mph can be expected for
locations generally along and west of Hwy 65 Sunday afternoon.
.LONG TERM...(Sunday night through Friday)
Issued at 330 AM CDT Sat Apr 23 2016
As the upper level low tracks east storms are expected to develop
to the west and northwest of the area along a cold front Sunday
evening. The front will then drop to the southeast into the area
Sunday night into Monday. The better lift and instability will
remain to the northwest and north of the area as the upper level
trough remains well north of the area. There will be an
instability gradient that sets up close to the far northwestern
portions of the area, so storms will be weakening as they move
southeast into the area, but a few strong storms may still be
possible generally northwest of a Pittsburg KS to Nevada MO line
Sunday night into early Monday morning. Coverage in storms will be
decreasing as the storms move into the area and will be isolated
to scattered in nature and many locations will remain dry. It is
also possible the storms dissipate just to the northwest of the
area.
As the front moves south through the area on Monday a few
thunderstorms will be possible, but overall most locations will
remain dry as coverage will be very limited with this activity.
Instability is expected to remain on the weak side, therefore,
not expecting a severe risk Monday.
Another upper level low will push into the northwestern U.S.
Sunday then dig to the south into the southwestern U.S. Monday
then lift to the northeast across the plains by Wednesday. As the
upper level low lifts to the northeast, the front that moves
south through the region Sunday night into Monday will lift back
to the north as a warm front Monday night into Tuesday morning.
Scattered storm chances will occur again along the front as it
lifts north.
Instability will then increase across the region on Tuesday ahead
of the approaching storm system, but a strong cap will also
develop across the area. The strong lift with this system will
remain well west of the area through the day on Tuesday, Therefore
most of the day should be dry after the warm front lifts north of
the area.
Storms are expected to develop across central Kansas
to the south into central Texas Tuesday evening along a cold
front. The front will then track east Tuesday night into Wednesday
Wednesday across the area. There is still some question on the
exact timing of the front but it will be at some point during the
day on Wednesday. There will be a severe risk with the storms
overnight Tuesday into Wednesday as the gulf moisture and an
unstable air mass will be in place across the area, large hail and
strong winds will be the main risk.
As the system moves off to the east mostly dry weather will occur
on Thursday. Then another system will begin to track into the
region Friday into the start of the weekend brining additional
chances for thunderstorms to the area.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1159 AM CDT Sat Apr 23 2016
VFR conditions are expected through the period as surface high
pressure continues to drift eastward and an upper level ridge
moves across the area. Main forecast concern is gusty winds
beginning after sunrise on Sunday as the next approaching system
begins to tighten up the surface pressure gradient. Winds should
develop gusts after 13z at KSGF/KJLN but believe that it will be
later in the afternoon...after the end of the forecast
period...for KBBG.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...Gaede
Area Forecast Discussion
National Weather Service Springfield MO
1206 PM CDT SAT APR 23 2016
.SHORT TERM...(Today through Sunday)
Issued at 330 AM CDT Sat Apr 23 2016
An upper level ridge is currently building over the region early
this morning and will be centered over the area by tonight. As an
upper level trough tracks east into the northern Plains on Sunday
the ridge will start to spread off Sunday night.
Warm and dry conditions will occur through much of this weekend
as highs warm into the upper 70s to the lower 80s both afternoons.
Sunny skies will occur today with partly cloudy skies occurring on
Sunday. Gusty southerly winds will develop Sunday afternoon as
surface low pressure develops across the central Plains ahead of
the upper level low. Wind gusts over 30 mph can be expected for
locations generally along and west of Hwy 65 Sunday afternoon.
.LONG TERM...(Sunday night through Friday)
Issued at 330 AM CDT Sat Apr 23 2016
As the upper level low tracks east storms are expected to develop
to the west and northwest of the area along a cold front Sunday
evening. The front will then drop to the southeast into the area
Sunday night into Monday. The better lift and instability will
remain to the northwest and north of the area as the upper level
trough remains well north of the area. There will be an
instability gradient that sets up close to the far northwestern
portions of the area, so storms will be weakening as they move
southeast into the area, but a few strong storms may still be
possible generally northwest of a Pittsburg KS to Nevada MO line
Sunday night into early Monday morning. Coverage in storms will be
decreasing as the storms move into the area and will be isolated
to scattered in nature and many locations will remain dry. It is
also possible the storms dissipate just to the northwest of the
area.
As the front moves south through the area on Monday a few
thunderstorms will be possible, but overall most locations will
remain dry as coverage will be very limited with this activity.
Instability is expected to remain on the weak side, therefore,
not expecting a severe risk Monday.
Another upper level low will push into the northwestern U.S.
Sunday then dig to the south into the southwestern U.S. Monday
then lift to the northeast across the plains by Wednesday. As the
upper level low lifts to the northeast, the front that moves
south through the region Sunday night into Monday will lift back
to the north as a warm front Monday night into Tuesday morning.
Scattered storm chances will occur again along the front as it
lifts north.
Instability will then increase across the region on Tuesday ahead
of the approaching storm system, but a strong cap will also
develop across the area. The strong lift with this system will
remain well west of the area through the day on Tuesday, Therefore
most of the day should be dry after the warm front lifts north of
the area.
Storms are expected to develop across central Kansas
to the south into central Texas Tuesday evening along a cold
front. The front will then track east Tuesday night into Wednesday
Wednesday across the area. There is still some question on the
exact timing of the front but it will be at some point during the
day on Wednesday. There will be a severe risk with the storms
overnight Tuesday into Wednesday as the gulf moisture and an
unstable air mass will be in place across the area, large hail and
strong winds will be the main risk.
As the system moves off to the east mostly dry weather will occur
on Thursday. Then another system will begin to track into the
region Friday into the start of the weekend brining additional
chances for thunderstorms to the area.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1159 AM CDT Sat Apr 23 2016
VFR conditions are expected through the period as surface high
pressure continues to drift eastward and an upper level ridge
moves across the area. Main forecast concern is gusty winds
beginning after sunrise on Sunday as the next approaching system
begins to tighten up the surface pressure gradient. Winds should
develop gusts after 13z at KSGF/KJLN but believe that it will be
later in the afternoon...after the end of the forecast
period...for KBBG.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...Gaede
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1140 AM CDT SAT APR 23 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 350 AM CDT Sat Apr 23 2016
Focus today will be clouds and temps.
Sfc ridge will continue to drift ewd today, allowing sly winds to
return to wrn portions of the CWA. Winds elsewhere are expected to
remain sely to ely.
The area of clouds currently just E of the CWA shud remain E.
However, some clouds may drift into ern portions of the CWA mainly
this morning until the ridge pushes them out of the area.
A secondary ridge axis over nrn portions of the CWA is expected to
be the focus for FG/stratus this morning. There is still uncertainty
regarding how widespread any FG will be, as well as any stratus. The
additional moisture within the bndy layer across this region shud
allow for at least sct clouds this morning, dissipating thru the
afternoon.
All of this leads to a rather complex temp forecast for today. For
ern portions of the CWA, have kept temps cooler where the ridge axis
will remain in place longer. Areas under this ridge yesterday saw
temps in the upper 60s, however, believe there will be less cloud
cover today. Believe the warmer temps will build into wrn portions
of the CWA where winds will become sly as well as the thermal ridge
building into this area. Have gone with trends close to a blend of
the RAP and local 4km WRF, which has been a good mix in these
setups. Did trend slightly cooler than this blend across nrn
portions of the CWA where more questions exist regarding cloud cover
today.
Tilly
.LONG TERM... (Tonight through Friday)
Issued at 350 AM CDT Sat Apr 23 2016
An upper level longwave RIDGE axis will persist over the Plains
thru much of next week, with upper longwave TROFs on the west and
east coasts. A series of strong Pacific storms will run thru this
RIDGE, being dropped off from the west coast TROF and being picked
up by the east coast TROF a few days later, with an overall track to
the E-NE thru our region. It would seem that each successive storm
system will track a bit further south than its predecessor.
The first storm system is slated to track to our north late Sunday
and into Monday, and will be mostly a glancing blow to our region as
a result, with what forms mostly upstream initially to our northwest
as it is thrown in our direction and largely weakens as it moves in.
This convection may also create additional boundaries during Monday
afternoon and early evening to maintain the threat for showers and
thunderstorms.
In the wake of this first storm system, a cold front will drop down
late Monday night into Tuesday and will maintain a low chance for
rain.
The second Pacific storm system will be more of a direct hit as it
will initially correspond well with the surface frontal boundary
buckling north as a warm front Wednesday morning. This should
result in elevated storms with hail as their primary threat during
that time.
Heading into Wednesday afternoon and evening, it will depend heavily
on how far north the front gets. Models have been trending with
less northward progress from 24hrs ago, but anywhere to the south of
it will have plenty of instability and moisture as well as strong
shear for more surface-based storms which will have a good potential
for some severe.
The rain potential lingers into Thursday if the cold front slows
enough to not make it thru until this day.
Friday should be a dry day, finally, but it appears only briefly
until yet another storm system approaches from the west in time for
the following weekend.
Otherwise, the longwave RIDGE setup will ensure that temps remain at
or above average throughout the period.
TES
&&
.AVIATION... (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1104 AM CDT Sat Apr 23 2016
Surface ridge extending from the Great Lakes region southwest
into eastern MO will shift eastward this period. The low level
cloudiness over eastern IA into northeast MO should remain north
of UIN this afternoon. The stratus cloudiness across southeast IL
should gradually dissipate this afternoon with daytime heating,
mixing and drying and remain east of the St Louis metro area.
There may be a few diurnal cumulus clouds at the taf sites this
afternoon. There will be a little high level cloudiness late
tonight and Sunday morning. Southeasterly surface winds should
strengthen at UIN and COU through the forecast period as the
surface pressure gradient gradually tightens, becoming more
southerly on Sunday. Light northeast wind in the St Louis metro
area will also strengthen as well through the period, veering
around to a southeast direction by early this evening, then
southerly Sunday morning. There will be some LLWS conditions in
UIN and COU very late tonight and early Sunday morning as a
southwesterly low level jet translates eastward into northwest MO
with both speed and directional shear in the lowest 1000 feet.
Specifics for KSTL: Stratus clouds across southeast IL should
gradually dissipate this afternoon and remain east-southeast of
STL. Few diurnal cumulus clouds may develop this afternoon due to
daytime heating, then dissipate early this evening. There will be
some high level cloudiness late tonight and Sunday. Light
northeast wind will increase in speed to 8-10 kts by late this
afternoon or early this evening as it veers around to a southeast
direction. The surface wind will become southerly Sunday morning
and possibly gusty Sunday afternoon.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
315 AM CDT SUN APR 24 2016
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 315 AM CDT SUN APR 24 2016
THE POTENTIAL FOR SEVERE STORMS TODAY IS THE MAIN FCST CONCERN.
CLOSED LOW AT 500 MB WAS NEAR THE UT/WY/CO BORDER AREA AT 00Z WITH
12 HOUR HEIGHT FALLS OF UP TO AROUND 80 METERS JUST AHEAD OF THE
CIRCULATION CENTER. THERE WAS A JET SEGMENT OF AROUND 70 KTS AT
300 MB NEAR THE UT/CO BORDER. AT 700 MB...THERMAL RIDGE AXIS
STRETCHED FROM SWRN NM UP INTO SERN MT. MOIST AXIS AT 850 MB
EXTENDED FROM TX INTO THE DKTS. WATER VAPOR STLT IMAGERY EARLY
THIS MORNING SHOWED THE MID TROPOSPHERIC LOW HAD PROGRESSED INTO
CENTRAL WY. SFC ANLYS AT 08Z HAD A LOW PRES CENTER OVER WRN SD.
A WMFNT EXTENDED E/NE FROM THE LOW INTO MN AND A CDFNT EXTENDED
S/SW INTO NERN NM. DEWPOINTS AHEAD OF THE CDFNT WERE IN THE UPPER
40S AND LOWER 50S.
TODAY...CURRENT SHOWERS AND TSTMS TO OUR WEST SHOULD MOVE INTO
THE AREA THIS MORNING BUT IT APPEARS THESE WILL STAY BELOW SVR
LIMITS. RECENT RUNS OF THE RAP AND HRRR MODELS DEPICT VIGOROUS
STORM DEVELOPMENT IN OUR AREA THIS AFTN. SFC-500 METER MIXED
LAYER CAPE VALUES COULD REACH AROUND 2000 J/KG BY MID AFTN IN OUR
WRN ZONES...BASED ON DEWPOINTS RISING TO THE MID/UPPER 50S. THE
STRONGEST STORMS SHOULD FORM THERE AND THEN DVLP EWD. ZERO TO 6 KM
SHEAR VALUES OF 35-45 KTS SHOULD BE ENOUGH FOR SOME SUPERCELLS...
WITH HAIL THE MOST LIKELY HAZARD. EXPERIMENTAL HRRR AND MANY OTHER
CONVECTION ALLOWING MODELS SHOW SIMILAR RESULTS. LOOK FOR HIGHS 75
TO 80.
STORMS SHOULD CONTINUE TO DVLP EWD AND MAINLY BE OUT OF THE AREA
BY 06Z TNGT. SOME SMALL CHANCE OF SHOWERS MAY LINGER INTO THE
EARLY MORNING HOURS...MAINLY NEAR THE SD BORDER. SFC LOW SHOULD BE
JUST NW OF KSUX BY 12Z MON...THEN THAT WILL MOVE TO NEAR THE
WI/IA/MN BORDER AREA BY 00Z TUE. NW SFC WINDS SHOULD PULL COOLER
AIR INTO NERN NE FOR MON...BUT COOLING WILL BE LESS FOR SERN NE
AND SWRN IA. THERE COULD BE SOME LGT PCPN IN OUR NRN COUNTIES MON
BUT FOR NOW KEPT MON INTO MON NGT DRY. OUR NEXT CHANCE OF SHOWERS
AND TSTMS WILL BE ON TUE...AS LOW PRES INTENSIFIES OVER ERN CO AND
WRN KS. LOCATION OF A NWD LIFTING WMFNT WILL BE CRITICAL...BUT IT
DOES APPEAR THERE WILL BE ENOUGH INSTABILITY IN SERN NE FOR SOME
STG TO SVR STORMS TUE AFTN AND EVENING.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 315 AM CDT SUN APR 24 2016
OVERALL THIS PERIOD LOOKS RATHER ACTIVE. DIFLUENT FLOW SHOULD BE
IN PLACE OVER THE AREA AT THE START OF THIS PERIOD...AHEAD OF A
CLOSED LOW IN SRN WY. WED COULD ALSO BE AN ACTIVE DAY WITH STORMS
BUT WITH FAIRLY WIDESPREAD CLOUDS AND PCPN SVR POTENTIAL IS NOT
CLEAR. IT DOES APPEAR THAT WE WILL DRY OUT THU INTO THU NGT...BUT
RAIN CHANCES SHOULD RETURN FRI AND PROBABLY LAST INTO THE WEEKEND.
&&
.AVIATION...(06Z TAFS FOR KOMA...KLNK...KOFK THROUGH 06Z MONDAY)
ISSUED AT 1133 PM CDT SAT APR 23 2016
PRIMARY AVIATION CONCERN REVOLVES AROUND 2 ROUNDS OF THUNDERSTORMS
THAT WILL AFFECT TAF SITES. THE FIRST WILL BE EARLY THIS MORNING
09-14Z. SECOND ROUND OF STORMS EXPECTED 21-02Z...WHICH WOULD BE
STRONGER WITH A SLIGHT RISK OF HAIL AND DAMAGING WINDS. SECONDARY
CONCERN IS NON CONVECTIVE LOW LEVEL WIND SHEAR...WITH WINDS AT
FLIGHT LEVEL 020 AROUND 45-50 KNOTS FROM NOW THROUGH ABOUT 11-14Z.
OTHERWISE VFR CONDITIONS PREVAIL WITH SOUTHEASTERLY WINDS AT 15
TO 30 KNOTS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1236 AM CDT SUN APR 24 2016
.UPDATE...
ISSUED AT 1225 AM CDT SUN APR 24 2016
TWEAKED PRECIPITATION CHANCES WITH THIS UPDATE. RAIN SHOWERS ARE
SLOW TO DEVELOP LATE TONIGHT. LATEST HIGH-RES DATA INDICATES A
SLIGHTLY DELAYED DEVELOPMENT OF PRECIPITATION COMPARED TO THE
PREVIOUS FORECASTS. THEREFORE DELAYED THE MENTION OF LIKELY
CHANCES TILL THIS MORNING. LOW LEVEL FRONTOGENESIS CONTINUES TO
STRENGTHEN TONIGHT...HOWEVER...THE MAIN UPPER LEVEL WAVE WAS STILL
LOCATED ACROSS SOUTH DAKOTA. THUNDERSTORMS STILL APPEAR POSSIBLE
ACROSS SOUTHERN NORTH DAKOTA. ISOLATED THUNDERSTORMS HAVE
DEVELOPED WEST OF THE BLACK HILLS IN ASSOCIATION WITH THE 700 MB
LOW.
UPDATE ISSUED AT 921 PM CDT SAT APR 23 2016
WIDELY SCATTERED SHOWERS NORTHEAST DECREASING. SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS APPROACHING THE SOUTHWEST. EXPECT
AROUND OR SHORTLY AFTER MIDNIGHT. CONTINUED BREEZY TO WINDY.
UPDATE ISSUED AT 636 PM CDT SAT APR 23 2016
DEEP LOW PRESSURE OVER WESTERN SOUTH DAKOTA AND HIGH PRESSURE
ACROSS MANITOBA WERE ENHANCING THE LOW LEVEL WINDS ACROSS NORTH
DAKOTA. MOST AREAS HAD EAST WINDS OF 20 TO 35 MPH WITH A FEW
SITES ABOVE 40 MPH. EXPECT THE WINDS TO CONTINUE TONIGHT. WATER
VAPOR CHANNEL SHOWS THE 700 MB UPPER LOW IN THE VICINITY OF WEST
CENTRAL WYOMING. SCATTERED THUNDERSTORMS HAVE DEVELOPED INTO SOUTH
CENTRAL MONTANA SOUTHEAST THROUGH EASTERN WYOMING. EXPECT THIS
AREA TO ROTATE NORTHEAST INTO SOUTHWEST NORTH DAKOTA LATE TONIGHT.
OTHERWISE FOR THE NEXT 6 HOURS OR SO LOOKING AT SOME INCREASING
CLOUDS AND A STEADY EAST WIND OF 20 TO 40 MPH.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 313 PM CDT SAT APR 23 2016
MAIN HIGHLIGHTS THROUGH SUNDAY AFTERNOON: RAINFALL AMOUNTS
ESPECIALLY LOCATIONS WHERE TOTALS EXCEED ONE INCH...A FEW STRONG
THUNDERSTORMS SOUTHWEST TONIGHT WITH POSSIBLE SMALL HAIL AND
GUSTY WINDS...AND POTENTIAL WIND ADVISORY TURTLE MOUNTAINS AND
VICINITY SUNDAY.
THE LATEST WATER VAPOR IMAGERY SHOWS A CLOSED UPPER LOW CIRCULATING
OVER FAR SOUTHEAST IDAHO WITH A DEEPENING SURFACE LOW
DOWNSTREAM...POSITIONED OVER NORTHEAST WYOMING. A WARM FRONT
EXTENDED FROM THIS LOW AND WAS DRAPED ALONG THE SOUTHERN BORDER.
WITH THIS WARM FRONT REMAINING JUST SOUTH OF OUR BORDER
TONIGHT/SUNDAY...AND THE UPPER LOW CATCHING UP WITH THE SURFACE
LOW AND BECOMING A VERTICALLY STACKED SYSTEM OVER CENTRAL SOUTH
DAKOTA...A WELL DEFINED DEFORMATION ZONE SETS UP OVER ALL OF
CENTRAL AND SOUTHERN NORTH DAKOTA LATER TONIGHT THROUGH SUNDAY.
FORCING/VERTICAL MOTION PER Q-VECTOR DIVERGENCE FIELD AND STEEP
MID LEVEL LAPSE RATES APPEAR MAXIMIZED BETWEEN INTERSTATE 94 AND
JUST SOUTH OF HIGHWAY 2. THIS SHOULD SET THE STAGE FOR PERIODS OF
HEAVIER RAINFALL AND HIGHEST RAINFALL TOTALS THROUGH SUNDAY.
EXPECT BETWEEN 1 AND 1.4 INCHES OF TOTAL RAINFALL THROUGH SUNDAY
NIGHT BETWEEN INTERSTATE 94 AND HIGHWAY 2.
THUNDERSTORM POTENTIAL REMAINS ELEVATED THROUGH THE PERIOD WITH
DECREASING CIN AS MOISTURE INCREASES THROUGH THE COLUMN AND
STEEPENING MID LEVEL LAPSE RATES. BEST CHANCES WILL BE TONIGHT
THROUGH SUNDAY MORNING...WITH SOUNDINGS BECOMING SATURATED AND
SHOWING RELATIVELY SKINNY OR NO CAPE FIELD. ENVIRONMENT SHOULD
TRANSITION MORE TOWARDS A HEAVY RAIN VERSUS CONVECTIVE IN NATURE.
SPC HAS MAINTAINED THE MARGINAL RISK FOR SEVERE THUNDERSTORMS IN
THE FAR SOUTHWEST TONIGHT. THINKING IS CONVECTION WOULD BEGIN AFTER
03Z PER LATEST HRRR AND GRADUALLY INCREASE OVERNIGHT INTO MID
MORNING SUNDAY.
GUSTY NORTHEAST WINDS WILL CONTINUE TONIGHT THROUGH SUNDAY ACROSS
ALL OF WESTERN AND CENTRAL NORTH DAKOTA. THE STRONGEST WINDS ARE
FORECAST ALONG AND NORTH OF HIGHWAY 2...WITH THE TURTLE MOUNTAINS
PINPOINTED FOR THE HIGHEST SUSTAINED WINDS OF AROUND 30 MPH AND
GUSTS TO 45 MPH. FUTURE SHIFTS CAN RE-EVALUATE FOR A POSSIBLE WIND
ADVISORY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 313 PM CDT SAT APR 23 2016
THE VERTICALLY STACKED SYSTEM CONTINUES TO SLOWLY SHIFT EAST
SUNDAY NIGHT AND MONDAY WITH A GRADUAL DECREASE IN POPS. HOWEVER
THE ECMWF HAS BEEN CONSISTENTLY ADVERTISING HIGHER QPF AND COLDER
AIR ESPECIALLY ALONG AND SOUTH OF INTERSTATE 94 MONDAY. THUS HAVE
TRENDED POPS BETWEEN CHC/LIKELY WITH MOSTLY RAIN AND A LITTLE BIT
OF SNOW EXPECTED. SNOWFALL ACCUMULATIONS OF A COUPLE TENTHS POSSIBLE
SUNDAY NIGHT ACROSS THE WEST.
ANOTHER ROUND OF PRECIPITATION IS POSSIBLE TUESDAY NIGHT THROUGH
WEDNESDAY NIGHT MAINLY ACROSS SOUTHERN NORTH DAKOTA. THE GFS AND
ECMWF CONTINUE TO BE AT ODDS IF THIS WILL OCCUR. THE GFS HAS BEEN
CONSISTENTLY SHOWING THE ABOVE...WHILE THE ECMWF IS NOT AS FAR
NORTH WITH THE PRECIPITATION SHIELD.
A BREAK IN THE PRECIPITATION THREAT IS POSSIBLE THURSDAY AND FRIDAY.
ANOTHER WET PERIOD SATURDAY BUT THE GFS AND ECMWF DIFFER ON PLACEMENT
OF THE PRECIPITATION AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1225 AM CDT SUN APR 24 2016
MAIN HAZARDS TO AVIATION WILL BE GUSTY EAST WINDS AND A DEVELOPING
RAIN THAT WILL USHER IN WIDESPREAD IFR CONDITIONS SUNDAY. SURFACE
LOW PRESSURE ACROSS WESTERN SOUTH DAKOTA WILL MAINTAIN A STRONG
EASTERLY WIND FLOW THROUGH THE PERIOD. VFR EXPECTED THROUGH
08Z...THEN RAPIDLY DETERIORATING CONDITIONS TO IFR IN RAIN AND BR
AFTER 08Z. ISOLATED THUNDERSTORMS ARE POSSIBLE NEAR KBIS/KDIK/KJMS
THIS MORNING...BUT CONFIDENCE AND COVERAGE IS NOT HIGH ENOUGH TO
WARRANT ANYTHING OTHER THAN A VICINITY MENTION.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AJ
SHORT TERM...KS
LONG TERM...KS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
428 AM CDT SUN APR 24 2016
.SHORT TERM /NOW THROUGH MONDAY/...A MID LEVEL SHORT WAVE TROUGH
WILL TRUNDLE ACROSS SOUTH CENTRAL TEXAS TODAY AND...WITH DAYTIME
HEATING...HAS PROMPTED A MARGINAL RISK OF SVR WEATHER CATEGORIZATION
FROM SPC. THE MAIN THREAT TODAY...AS SCATTERED THUNDERSTORMS DEVELOP
AND MOVE ACROSS THE AREA...WILL BE STRONG WIND GUSTS...FREQUENT
LIGHTNING...SMALL HAIL AND BRIEF HEAVY DOWNPOURS.
A ROUND OF SHOWERS AND THUNDERSTORMS HAS ALREADY MOVED THROUGH THE
AREA THIS MORNING...CONFIRMING THE THREAT FOR LIGHTNING...BRIEF
DOWNPOURS AND GUSTY WINDS...BUT RADAR ALSO SHOWS MORE DEVELOPMENT TO
THE SOUTH...AND THERE IS NO REASON TO BELIEVE THAT SOME CONVECTION
WILL NOT KEEP COMING THROUGH THE DAY. THE HRRR AND NAM SHOW SOME QPF
OVER EASTERN SECTIONS.
CONVECTION SHOULD END THIS EVENING...EXCEPT POSSIBLY FOR THE MARINE
AREAS...WITH IMPROVING CONDITIONS. LOOK FOR MODERATE SOUTHEAST WINDS
AND A MIX OF CLOUDS AND SUN ON MONDAY. HIGH TEMPS WILL RANGE FROM
THE 80S AT THE COAST TO THE UPPER 90S FAR WEST.
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...THE ONLY OPPORTUNITY
FOR PRECIPITATION DURING THE LONG TERM PORTION OF THE FORECAST
WILL OCCUR ON WEDNESDAY...AS THE INTRUSION OF A WEAK COLD FRONT
INTO DEEP SOUTH TEXAS AND THE RIO GRANDE VALLEY COMBINES WITH
DECENT AVAILABLE MOISTURE AND DAYTIME HEATING TO PRODUCE ISOLATED
SHOWERS AND THUNDERSTORMS. THE REMAINDER OF THE FORECAST WILL BE
DRY WITH NO OTHER COLD FRONT PASSAGES OR SIGNIFICANT DISTURBANCES
AT THE 500 MB LEVEL. MAINLY PARTLY CLOUDY SKIES WILL SUPPORT WELL
ABOVE NORMAL DAYTIME HIGH AND OVERNIGHT LOW TEMPERATURES.
&&
.MARINE...NOW THROUGH MONDAY...LIGHT SOUTHEAST WINDS WILL INCREASE
TO HIGH END MODERATE THIS AFTERNOON AS HIGH PRESSURE OVER THE
NORTHWEST GULF INTERACTS WITH LOWER PRESSURE OVER THE HIGH PLAINS.
MODERATE WINDS WILL CONTINUE TONIGHT AND SEAS WILL BUILD...WITH
POSSIBLE SMALL CRAFT SHOULD EXERCISE CAUTION CONDITIONS. HIGH END
MODERATE WINDS WILL REPEAT ON MONDAY. SHOWERS AND THUNDERSTORMS
WILL BE POSSIBLE TODAY AS AN UPPER DISTURBANCE INFLUENCES THE
AREA.
MONDAY NIGHT THROUGH SATURDAY...SMALL CRAFT EXERCISE CAUTION
AND SMALL CRAFT ADVISORY WILL DOMINATE THROUGHOUT THE LONG
TERM PORTION OF THE MARINE FORECAST...WITH HIGH PRESSURE OVER
THE GULF OF MEXICO INTERACTING WITH LOWER PRESSURE INLAND.
&&
.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL 82 74 86 74 / 60 20 10 0
BROWNSVILLE 84 74 87 74 / 70 20 0 0
HARLINGEN 85 73 91 74 / 60 20 0 0
MCALLEN 89 73 94 74 / 30 10 0 0
RIO GRANDE CITY 91 72 98 73 / 40 20 0 0
SOUTH PADRE ISLAND 79 74 82 73 / 70 20 10 0
&&
.BRO WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
SHORT TERM...MILLER-54
LONG TERM...TOMASELLI-66
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1145 PM CDT SAT APR 23 2016
.AVIATION...
VFR CONDS EXPECTED THROUGH ABOUT 09Z. MIGHT GET SOME SHALLOW
GROUND FOG ONCE AGAIN BUT CIRRUS STREAMING INTO THE AREA WILL
LIMIT COVERAGE AND INTENSITY. WATER VAPOR CONTS TO SHOW A WELL
DEFINED S/WV OVER NORTHERN MEXICO HEADING TOWARD SE TX AND FEEL
THIS DISTURBANCE WILL TRIGGER SHRA/TSRA BY 18Z WITH SHRAS
BEGINNING AS EARLY AS 15-16Z. FCST SOUNDINGS SHOWING BETTER
POTENTIAL FOR PRECIP COVERAGE WITH THE NAM/GFS/ECMWF ALL LOOKING
SIMILAR. PW VALUES INCREASE TO 1.73 INCHES WITH CAPE AROUND 1000.
43
&&
.PREV DISCUSSION... /ISSUED 1010 PM CDT SAT APR 23 2016/
UPDATE...
CONVECTION CONTINUES TO DEVELOP ALONG THE LOWER RIO GRANDE THIS
EVENING ASSOCIATED WITH A COMPACT SHORTWAVE PUSHING EAST INTO THE
STATE. EXPECT HIGH CLOUDS ASSOCIATED WITH THIS ACTIVITY TO
OVERSPREAD THE REGION FROM THE WEST/SOUTHWEST TONIGHT. THINK MOST
OF THE REGION WILL STAY DRY TONIGHT... BUT ADDED CHANCE/30 POPS
OVER THE SOUTHWESTERN COUNTIES/MATAGORDA BAY AREA SUNDAY MORNING
WITH THE APPROACH OF THE SHORTWAVE AND LOW LEVEL MOISTURE RETURN
OCCURRING MUCH QUICKER THAN WHAT PRELIMINARY 00Z GUIDANCE AND THE
LATEST RAP ARE SUGGESTING. THE KHGX VAD WIND PROFILE ALREADY SHOWS
SOUTHERLY FLOW 15-20 KNOTS THROUGH 5KFT... WITH THE GUIDANCE
INSISTING ON A MORE BACKED/DRIER FLOW PERSISTING UNTIL AFTER 06Z.
OTHERWISE... EXPECT OVERNIGHT LOWS TO FALL INTO THE UPPER 50S TO
MID 60S.
HUFFMAN
PREV DISCUSSION... /ISSUED 318 PM CDT SAT APR 23 2016/
DISCUSSION...
GIVEN THE WAY THIS WEEK STARTED...GREAT TO END THE WEEK WITH SOME
BEAUTIFUL WEATHER ACROSS SE TEXAS. TEMPERATURES HAVE REACHED THE
LOW 80S WITH LOW HUMIDITY THIS AFTERNOON. ONE CANNOT ASK FOR MUCH
BETTER WEATHER TO BE OUTSIDE.
SUNDAY AN UPPER LEVEL TROUGH SHOULD MOVE OVER THE REGION DURING
THE AFTERNOON AND EVENING. WATER VAPOR SATELLITE IMAGERY SHOWS
THIS SYSTEM OVER MEXICO. THE FORECAST WILL KEEP SOME HIGHER RAIN
CHANCES OFF TO THE SOUTHWEST OF HOUSTON BUT LOOKS LIKE THOSE
CHANCES DIMINISH TOWARDS THE EVENING HOURS. OUTSIDE OF THE
CANADIAN MODEL...MOST MODELS INCLUDING HIGH RESOLUTION CONVECTIVE
ALLOWING MODELS DO NOT PRODUCE MUCH CONVECTION. GFS SEEMS TO BE ON
THE HIGH END FOR QPF BUT EVEN IT ENDS PRECIPITATION IN THE
EVENING. REGARDLESS CLOUD COVER SHOULD INCREASE ACROSS THE AREA
AND HOLD TEMPERATURES IN THE LOW 80S AS MOISTURE RETURNS.
WATER VAPOR IMAGERY SHOWS ANOTHER STRONG UPPER LOW AND JET STREAM
OUT OVER THE PACIFIC AND GULF OF ALASKA. THIS SYSTEM SHOULD PULL
INTO THE ROCKIES TUESDAY MORNING AND INTO THE PLAINS BY 00Z
WEDNESDAY. THIS SYSTEM WILL PROVIDE A FAVORABLE SET UP FOR SEVERE
WEATHER ACROSS THE PLAINS. ACROSS SOUTHEAST TEXAS...FAIRLY STRONG
CAP IS EXPECTED TO DEVELOP WHICH SHOULD RESTRICT CONVECTIVE
DEVELOPMENT. THERE STILL MAY BE SOME PASSING SHOWERS DUE TO
MOISTURE/WARM AIR ADVECTION PATTERN. A TRAILING PACIFIC FRONT OR
DRY LINE MAY PUSH INTO THE AREA AND STALL ON WEDNESDAY SO
MAINTAINED 30/40 POPS FOR THE REGION. THE GFS AND ECMWF HAVE SOME
DIFFERENCES IN THIS EVOLUTION WITH THE ECMWF MORE AGGRESSIVE WITH
PRECIP CHANCES. THAT SAID...GFS MODEL SOUNDINGS SHOW THE CAP
WEAKENING ON WEDNESDAY.
IN THE EXTENDED FORECAST...WE WILL NEED TO KEEP AN EYE ON THE NEXT
SYSTEM AFTER THE MIDWEEK SYSTEM. BOTH GFS/ECMWF DEPICT A DEEP
TROUGH OVER THE SOUTHERN ROCKIES. ECMWF IS MORE CONCERNING SINCE
IT HAS A BETTER DIFFLUENT JET STRUCTURE WHICH WOULD ALLOW FOR A
WEAKER CAP AND WIDESPREAD CONVECTION. THIS IS A MODEL SIGNAL THAT
MAY NEED TO BE MONITORED IN THE MODEL RUNS FOR THE NEXT FEW DAYS.
THE ECMWF SOLUTION WILL LARGELY DEPEND ON HOW DEEP THE TROUGH
DEVELOPS OVER THE SOUTHERN ROCKIES INTO MEXICO.
OVERPECK
MARINE...
LIGHT OFFSHORE WINDS WILL PREVAIL OVER THE COASTAL WATERS TONIGHT.
OVER THE BAYS THE BRIEF ONSHORE FLOW IN THE WAKE OF THE SEABREEZE
SHOULD GIVE WAY TO A LIGHT ELY FLOW OVERNIGHT. WITH THE SFC HIGH
MOVING FURTHER EAST OF THE REGION TOMORROW...ONSHORE WINDS ARE EX-
PECTED TO RETURN ACROSS THE AREA TOMORROW...STRENGTHENING THROUGH
MUCH OF THE UPCOMING WEEK IN RESPONSE TO A SERIES OF DISTURBANCES
MOVING IN FROM THE SW. WE COULD SEE CAUTION FLAGS OVER THE MARINE
WATERS STARTING MON NIGHT ON INTO THURS. 41
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 60 81 67 84 69 / 10 20 20 10 10
HOUSTON (IAH) 61 81 67 83 70 / 10 20 20 10 10
GALVESTON (GLS) 68 77 71 79 73 / 10 30 20 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...14
AVIATION/MARINE...43
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1130 PM CDT SAT APR 23 2016
.AVIATION...
BREEZY SOUTH WINDS TO VEER TO SW AS AN UPPER LEVEL SHORT WAVE
TROUGH MOVES ACROSS THE HIGH PLAINS. THERE IS AN OUTSIDE CHANCE
FOR STRATUS TO DEVELOP VCNTY KLBB AND KPVW AROUND 12Z SUNDAY.
CHANCE IS VERY LOW AND WILL TAFS VFR THROUGH THE PERIOD.
&&
.PREV DISCUSSION... /ISSUED 627 PM CDT SAT APR 23 2016/
AVIATION...
AN UPPER LEVEL SHORT WAVE TROUGH WILL EJECT FROM THE COLORADO
ROCKIES ONTO THE CENTRAL HIGH PLAINS SUNDAY MORNING. SFC PRESSURE
GRADIENT WILL REMAIN TIGHT...KEEPING SOUTH WINDS BREEZY OVERNIGHT
THEN VEERING TO SOUTHWEST SUNDAY MORNING. LOW LEVEL MOISTURE
RETURN OVERNIGHT...BUT ANY STRATUS SHOULD STAY TO THE SOUTH.
PREV DISCUSSION... /ISSUED 349 PM CDT SAT APR 23 2016/
SHORT TERM...
THE DRYLINE HAS BEEN SITTING IN EASTERN NM FOR SOME TIME TODAY AND
SHOULD STAY THERE...FOR THE MOST PART... UNTIL THE UPPER LEVEL LOW
PUSHES CLOSER TO THE REGION. CONVECTION ALONG THE DRYLINE STILL
LOOKS UNLIKELY AS LIFT LOOKS TO BE HARD TO COME BY. THE BEST CHANCE
FOR LIFT WOULD BE WITH THE DRYLINE. THE BEST SURFACE CONVERGENCE
ALONG THE DRYLINE IS NORTH IN THE TEXAS PANHANDLE. A LOCALIZED AREA
OF ENHANCE CONVERGENCE HAS RECENTLY SET UP OVER THE TX/NM STATE LINE
AROUND PARMER COUNTY. THIS HAS RESULTED IN A SHALLOW CU FIELD.
ENOUGH LIFT FOR ISOLATED SHOWER DEVELOPMENT IS NOT OUT OF THE
QUESTION...HOWEVER THUNDERSTORM DEVELOPMENT IS NOT HIGH ON THE
EXPECTATION LIST. THIS IS DUE TO CONVECTION HAVING TO OVERCOME A
SUBSIDENCE INVERSION IN THE UPPER-MID LEVELS AS WELL AS THERE BEING
A LACK OF CAPE. THE HRRR SEEMS TO BE THE MOST GENEROUS OF THE MODELS
IN HANDING OUT CAPE WHICH IS ONLY A COUPLE HUNDRED J/KG AT BEST
ACROSS OUR NORTHWESTERN ZONES. FOR NOW THE FORECAST WILL REFLECT A
MENTION OF ISOLATED SHOWERS BEFORE 1 AM AND NO MENTION OF THUNDER.
WINDS WILL STAY GUSTY INTO THE NIGHT AHEAD OF AND BEHIND THE
DRYLINE. WINDS WILL BE MOSTLY OUT OF THE WEST BY EARLY TOMORROW
AFTERNOON ACROSS THE CAPROCK AND WILL INCREASE TO THE 25 MPH RANGE
AS THE MAIN ENERGY FROM THE UPPER LOW PASSES TO OUR NORTH. ALDRICH
LONG TERM...
WARM...DRY AND BREEZY CONDITIONS ARE IN STORE THROUGH TUESDAY.
THE SECOND IN A SERIES OF UPPER LOWS/TROUGHS WILL SWING ACROSS THE
SOUTHERN HIGH PLAINS TUESDAY AFTERNOON...PRODUCING THE WINDIEST
DAY OF THE PERIOD. GFS MOS GUIDANCE CONTINUES TO HOVER AROUND 30
TO 34 KTS AT LUBBOCK...WHILE THE MET IS AROUND 20 KTS. WE
CONTINUE TO PLY THE MIDDLE-GROUND AT AROUND 25 KTS OR SO...OR 25
TO 30 MPH WITH GUSTS TO AROUND 40 MPH. HIGH TEMPS MONDAY AND
TUESDAY SHOULD BE IN THE 80S TO LOW 90S. WE HAVE RETAINED A SLIVER
OF T-STORM CHANCES IN THE SRN ROLLING PLAINS LATE THURSDAY...BUT
THE LATEST INDICATIONS ARE THAT THE DRYLINE WILL BE TO THE EAST OF
THE AREA...BUT IT IS NOT OUT OF THE QUESTION SOME STORMS COULD
DEVELOP IN THAT AREA AS THE DRYLINE RETREATS SOMEWHAT IN THE
EVENING. WEDNESDAY SHOULD BE SLIGHTLY COOLER AS FLOW SWITCHES TO
NORTHWEST...THEN A COLD FRONT WILL MOVE THROUGH WEDNESDAY NIGHT OR
EARLY THURSDAY. THE NEXT UPPER LOW IS STILL FORECAST TO DIG INTO
THE DESERT SOUTHEAST MIDWEEK WITH NOT MUCH CHANGE IN TRACK THE
PAST 24 HRS. SURFACE RIDGING...A STRENGTHENING SRLY LOW-LEVEL JET
AND SW FLOW ALOFT THURSDAY SHOULD RETURN GULF MOISTURE INTO THE
AREA AND ALONG WITH SOME ISENTROPIC UPGLIDE...BEGIN TO INCREASE
PRECIP CHANCES. DURING THE DAY THURSDAY THESE CHANCES MAY BE
CONFINED TO OUR SRN AND ERN COUNTIES WHERE THE DEEPER MOISTURE IS
EXPECTED TO BE NOSING IN FROM THE SOUTH. THURSDAY NIGHT INTO
FRIDAY MORNING WE COULD SEE SHOWER AND T-STORM ACTIVITY INCREASE
AS LARGE-SCALE ASCENT FROM THE UPPER LOW BEGINS TO SPREAD OVER THE
REGION. BY FRIDAY...THE MED- RANGE SOLUTIONS BEGIN TO DIVERGE WITH
THE SURFACE DETAILS AS THE GFS BRINGS A DRYLINE INTO THE AREA
WHILE THE ECMWF MAINTAINS SURFACE RIDGING. OVERALL...THE PATTERN
CERTAINLY APPEARS FAVORABLE FOR T-STORM ACTIVITY...AND POSSIBLY
SEVERE WEATHER...BUT AS USUAL THE CONFIDENCE IN THE DETAILS IS LOW
THIS FAR OUT. THE UPPER- TROUGH IS CURRENTLY EXPECTED TO PASS
ACROSS WEST TEXAS DURING THE DAY SATURDAY...DRAGGING PRECIP.
CHANCES EASTWARD WITH IT.
FIRE WEATHER...
THE FIRE DANGER WILL BECOME ELEVATED ACROSS MUCH OF THE CAPROCK
EACH AFTERNOON SUNDAY THROUGH TUESDAY. CONDITIONS WILL LIKELY BE
THE WORST ON TUESDAY AS A PASSING STORM SYSTEM BRINGS STRONGER
WIND SPEEDS. HOWEVER...THE OVERALL FIRE DANGER WILL BE REDUCED BY
THE SEASONAL GREEN-UP ACROSS THE AREA.
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
935 AM MDT SUN APR 24 2016
.UPDATE...
ISSUED AT 922 AM MDT SUN APR 24 2016
GUSTY WINDS INCREASING ACROSS THE THE CWA THIS MORNING. RADAR
SHOWING SOME LIGHT SHOWERS ASSOCIATED WITH THE WRAP AROUND MSTR
DROPPING OUT OF WY AND SWINGING ACROSS NORTHERN WELD COUNTY THIS
MORNING. HAVE ADJUSTED TO POPS NORTH OF DENVER TO DROP THE PCPN A
LITTLE FURTHER SOUTH. RUC13 SPATIAL CROSS-SECTIONS SHOW STRONGEST
WINDS IN THE FOOTHILLS WILL BE IN THE 16-18Z PERIOD...WHERE SOME
GUSTS TO AROUND 70 MPH WILL BE POSSIBLE. MADE SOME MINOR
ADJUSTMENTS TO THE MAX TEMPERATURES AS WELL...LOWERED THEM BY A
COUPLE OF DEGREES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 410 AM MDT SUN APR 24 2016
AN UPPER LEVEL STORM SYSTEM IS OVER SERN WY THIS MORNING AND WILL
MOVE SLOWLY EAST INTO NC NEBRASKA/SCNTRL SOUTH DAKOTA BY THIS
EVENING. SOME MOISTURE WILL ROTATE AROUND THE UPPER LEVEL LOW AND
COMBINED WITH DECENT OROGRAPHICS WILL PRODUCE SNOW IN THE NRN MTNS
THRU THE AFTN. BEST CHC WILL BE ACROSS ZN 31 AND WRN PORTIONS OF ZN
33. SNOWFALL AMOUNTS WILL BE IN THE 2 TO 4 INCH RANGE.
MEANWHILE A DISTURBANCE OVER NCTRL CO EARLY THIS MORNING WILL MOVE
ACROSS NERN CO BY EARLY AFTN. THERE WILL BE SOME WDLY SCT HIGH
BASED SHOWERS WITH THIS FEATURE ESPECIALLY NR THE WY-NE BORDER AREA.
AS FOR WINDS AM STILL A LITTLE CONCERNED THAT THERE WILL BE A PERIOD
OF STRONGER WINDS OVER PORTIONS OF THE HIGHER FOOTHILLS AND MTN
AREAS FM MID MORNING THRU MID AFTN. THE NORMAL WINDY AREAS WILL
LIKELY SEE A FEW GUSTS FM 70 TO 80 MPH DURING THIS PERIOD BUT THE
QUESTION IS HOW WIDESPREAD WILL THEY BE. AT THIS POINT CONFIDENCE
IS NOT HIGH AS TO HOW WIDESPREAD THEY WILL BE SO WILL NOT ISSUE A
WARNING FOR NOW. ACROSS THE PLAINS WILL LIKELY SEE GUSTS TO 50 MPH
AT TIMES NEAR THE WY BORDER WITH UP TO 40 MPH ACROSS THE REST OF
THE PLAINS BY MIDDAY. AS FOR HIGHS THIS AFTN READINGS WILL BE IN
THE MID 60S TO AROUND 70 ACROSS NERN CO.
FOR TONIGHT DRIER AIR WILL SPREAD ACROSS THE NRN MTNS SO ONLY EXPECT
A SLIGHT CHC OF -SHSN THRU THE EVENING HOURS. ACROSS THE PLAINS IT
WILL BE DRY. WINDS WILL CONTINUE GUSTY EARLY THIS EVENING ACROSS
THE PLAINS AND HIGHER TERRAIN BUT SHOULD GRADUALLY DECREASE BY LATE
EVENING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 410 AM MDT SUN APR 24 2016
THERE IS UPPER RIDGING OVER THE CWA MONDAY. THE NEXT UPPER
TROUGH/CLOSED LOW GETS INTO COLORADO BY 06Z MONDAY NIGHT. THE
VARIOUS MODELS BRING THE CIRCULATION CENTER FROM THE NORTHWESTERN
COLORADO CORNER AT 18Z TUESDAY TO THE NORTHEASTERN CORNER OF
COLORADO BY 12Z WEDNESDAY MORNING. THE FLOW ALOFT IS SOUTHWESTERLY
MONDAY AND MONDAY NIGHT. IT IS DUE SOUTHERLY TUESDAY...THEN WEAK
TUESDAY NIGHT WITH THE UPPER LOW RIGHT OVER THE CWA. THERE IS
PRETTY DECENT UPWARD QG VERTICAL VELOCITY OVER THE CWA MONDAY
INTO WEDNESDAY MORNING. THE BOUNDARY LAYER FLOW IS PROGGED TO BE
SOUTHEASTERLY ON MONDAY...EVEN MORE EASTERLY MONDAY NIGHT. ON
TUESDAY A SURFACE CYCLONE IS DEVELOPING OVER SOUTHEASTERLY
COLORADO WITH UPSLOPE FOR THE PLAINS AND FOOTHILLS. MORE NORTH-
NORTHWESTERLY WINDS ARE PROGGED TUESDAY NIGHT. THERE IS SOME
MOISTURE AROUND MONDAY AND MONDAY NIGHT...MORE SO IN THE
MOUNTAINS. THE MOISTURE IS MORE WIDESPREAD AND DEEPER ON TUESDAY
WITH THE UPPER LOW AROUND. THERE IS SOME MINOR CAPE AROUND OVER
THE MOUNTAINS LATE DAY MONDAY. THE CAPE IS MORE WIDESPREAD LATE
DAY TUESDAY WITH SOME VALUES OVER 1000 J/KG OVER THE FAR NORTHEAST
CORNER. THE LAPSE RATES ARE PRETTY STEEP BOTH LATE DAY PERIODS OF
MONDAY AND TUESDAY. THE QPF FIELDS HAVE MINOR AMOUNTS OF
MEASURABLE PRECIPITATION FOR THE CWA LATE DAY MONDAY INTO TUESDAY
MORNING. THERE IS A BIT MORE NOTED FOR MOST AREAS TUESDAY
AFTERNOON AND NIGHT. FOR POPS...WILL MAINLY HAVE "CHANCE"S IN FROM
MONDAY AFTERNOON THROUGH TUESDAY NIGHT. WILL HAVE "LIKELY"S FOR
LATE DAY TUESDAY. FOR TEMPERATURES...MONDAY`S HIGHS ARE 1-3 C
WARMER THAN TODAY`S. TUESDAY`S HIGHS ARE 4-11 C COLDER THAN
MONDAY`S FOR THE LATER DAYS...WEDNESDAY THROUGH SATURDAY...MODELS
HAVE WEAK UPPER RIDGING FOR THE CWA WEDNESDAY INTO THURSDAY
MORNING...THEN SOUTH OR SOUTHWESTERLY FLOW ALOFT INTO FRIDAY
...WITH THE NEXT UPPER TROUGH/CLOSED LOW TO MOVE IN LATER THURSDAY
NIGHT THROUGH FRIDAY NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 922 AM MDT SUN APR 24 2016
VFR THRU MONDAY MORNING. STILL EXPECT STRONG WINDS TODAY WITH
SUBSIDENCE ACROSS THE AREA. SHOULD SEE DECENT MIXING OF STRONGER
FLOW ALOFT THRU THE AFTN HOURS. WINDS AT DIA WLY AT THIS TIME AND
SHOULD BE WEST-NORTHWEST BY 18Z. WILL SEE A FEW GUSTS TO 25 KTS
THRU 18Z WITH GUSTS FM 30-35 KTS AFTER 18Z. WINDS SHOULD SLOWLY
DECREASE BY 23Z INTO THE EARLY EVENING HOURS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...COOPER
SHORT TERM...RPK
LONG TERM...RJK
AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
418 AM MDT SUN APR 24 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 410 AM MDT SUN APR 24 2016
AN UPPER LEVEL STORM SYSTEM IS OVER SERN WY THIS MORNING AND WILL
MOVE SLOWLY EAST INTO NC NEBRASKA/SCNTRL SOUTH DAKOTA BY THIS
EVENING. SOME MOISTURE WILL ROTATE AROUND THE UPPER LEVEL LOW AND
COMBINED WITH DECENT OROGRAPHICS WILL PRODUCE SNOW IN THE NRN MTNS
THRU THE AFTN. BEST CHC WILL BE ACROSS ZN 31 AND WRN PORTIONS OF ZN
33. SNOWFALL AMOUNTS WILL BE IN THE 2 TO 4 INCH RANGE.
MEANWHILE A DISTURBANCE OVER NCTRL CO EARLY THIS MORNING WILL MOVE
ACROSS NERN CO BY EARLY AFTN. THERE WILL BE SOME WDLY SCT HIGH
BASED SHOWERS WITH THIS FEATURE ESPECIALLY NR THE WY-NE BORDER AREA.
AS FOR WINDS AM STILL A LITTLE CONCERNED THAT THERE WILL BE A PERIOD
OF STRONGER WINDS OVER PORTIONS OF THE HIGHER FOOTHILLS AND MTN
AREAS FM MID MORNING THRU MID AFTN. THE NORMAL WINDY AREAS WILL
LIKELY SEE A FEW GUSTS FM 70 TO 80 MPH DURING THIS PERIOD BUT THE
QUESTION IS HOW WIDESPREAD WILL THEY BE. AT THIS POINT CONFIDENCE
IS NOT HIGH AS TO HOW WIDESPREAD THEY WILL BE SO WILL NOT ISSUE A
WARNING FOR NOW. ACROSS THE PLAINS WILL LIKELY SEE GUSTS TO 50 MPH
AT TIMES NEAR THE WY BORDER WITH UP TO 40 MPH ACROSS THE REST OF
THE PLAINS BY MIDDAY. AS FOR HIGHS THIS AFTN READINGS WILL BE IN
THE MID 60S TO AROUND 70 ACROSS NERN CO.
FOR TONIGHT DRIER AIR WILL SPREAD ACROSS THE NRN MTNS SO ONLY EXPECT
A SLIGHT CHC OF -SHSN THRU THE EVENING HOURS. ACROSS THE PLAINS IT
WILL BE DRY. WINDS WILL CONTINUE GUSTY EARLY THIS EVENING ACROSS
THE PLAINS AND HIGHER TERRAIN BUT SHOULD GRADUALLY DECREASE BY LATE
EVENING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 410 AM MDT SUN APR 24 2016
THERE IS UPPER RIDGING OVER THE CWA MONDAY. THE NEXT UPPER
TROUGH/CLOSED LOW GETS INTO COLORADO BY 06Z MONDAY NIGHT. THE
VARIOUS MODELS BRING THE CIRCULATION CENTER FROM THE NORTHWESTERN
COLORADO CORNER AT 18Z TUESDAY TO THE NORTHEASTERN CORNER OF
COLORADO BY 12Z WEDNESDAY MORNING. THE FLOW ALOFT IS SOUTHWESTERLY
MONDAY AND MONDAY NIGHT. IT IS DUE SOUTHERLY TUESDAY...THEN WEAK
TUESDAY NIGHT WITH THE UPPER LOW RIGHT OVER THE CWA. THERE IS
PRETTY DECENT UPWARD QG VERTICAL VELOCITY OVER THE CWA MONDAY
INTO WEDNESDAY MORNING. THE BOUNDARY LAYER FLOW IS PROGGED TO BE
SOUTHEASTERLY ON MONDAY...EVEN MORE EASTERLY MONDAY NIGHT. ON
TUESDAY A SURFACE CYCLONE IS DEVELOPING OVER SOUTHEASTERLY
COLORADO WITH UPSLOPE FOR THE PLAINS AND FOOTHILLS. MORE NORTH-
NORTHWESTERLY WINDS ARE PROGGED TUESDAY NIGHT. THERE IS SOME
MOISTURE AROUND MONDAY AND MONDAY NIGHT...MORE SO IN THE
MOUNTAINS. THE MOISTURE IS MORE WIDESPREAD AND DEEPER ON TUESDAY
WITH THE UPPER LOW AROUND. THERE IS SOME MINOR CAPE AROUND OVER
THE MOUNTAINS LATE DAY MONDAY. THE CAPE IS MORE WIDESPREAD LATE
DAY TUESDAY WITH SOME VALUES OVER 1000 J/KG OVER THE FAR NORTHEAST
CORNER. THE LAPSE RATES ARE PRETTY STEEP BOTH LATE DAY PERIODS OF
MONDAY AND TUESDAY. THE QPF FIELDS HAVE MINOR AMOUNTS OF
MEASURABLE PRECIPITATION FOR THE CWA LATE DAY MONDAY INTO TUESDAY
MORNING. THERE IS A BIT MORE NOTED FOR MOST AREAS TUESDAY
AFTERNOON AND NIGHT. FOR POPS...WILL MAINLY HAVE "CHANCE"S IN FROM
MONDAY AFTERNOON THROUGH TUESDAY NIGHT. WILL HAVE "LIKELY"S FOR
LATE DAY TUESDAY. FOR TEMPERATURES...MONDAY`S HIGHS ARE 1-3 C
WARMER THAN TODAY`S. TUESDAY`S HIGHS ARE 4-11 C COLDER THAN
MONDAY`S FOR THE LATER DAYS...WEDNESDAY THROUGH SATURDAY...MODELS
HAVE WEAK UPPER RIDGING FOR THE CWA WEDNESDAY INTO THURSDAY
MORNING...THEN SOUTH OR SOUTHWESTERLY FLOW ALOFT INTO FRIDAY
...WITH THE NEXT UPPER TROUGH/CLOSED LOW TO MOVE IN LATER THURSDAY
NIGHT THROUGH FRIDAY NIGHT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 410 AM MDT SUN APR 24 2016
VFR TODAY THRU TONIGHT. MAIN PROBLEM TODAY WILL BE THE WINDS.
WITH SUBSIDENCE ACROSS THE AREA SHOULD SEE DECENT MIXING OF STRONGER
FLOW ALOFT LATE THIS MORNING THRU THE AFTN HOURS. WINDS AT DIA
EARLY THIS MORNING HAVE SWITCHED BACK TO MORE SSW HOWEVER THEY
SHOULD GRADUALLY BECOME MORE WLY BY 15Z AND THEN WNW BY 18Z. MAY
SEE A FEW GUSTS TO 25 MPH BETWEEN 15Z AND 18Z WITH GUSTS FM 30 TO 35
AFTER 18Z. WINDS SHOULD SLOWLY DECREASE BY 23Z INTO THE EARLY
EVENING HOURS. THE RAP HAS WINDS BECOMING LIGHT NLY BY 02Z WHILE
THE HRRR HAS MORE OF A WSW DIRECTION. WILL TREND TOWARDS A MORE
WSW COMPONENT WITH SSW WINDS BY 06Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RPK
LONG TERM...RJK
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
737 AM EDT SUN APR 24 2016
.AVIATION...AREAS OF FOG ARE BEING REPORTED REDUCING THE
VISIBILITY TO LIFR AT LAL/PGD. THIS FOG IS EXPECTED TO BURN OFF
PRETTY QUICK THIS MORNING SO WILL KEEP A TEMPO GROUP UNTIL
13Z...THEN BECOMING VFR FOR ALL TERMINALS. A BRIEF SHOWER WILL BE
POSSIBLE LATER TODAY AS THE SEA BREEZE FORMS UP AFTER 19Z SO WILL
COVER THIS WITH VCSH. NO OTHER AVIATION IMPACTS EXPECTED.
&&
.PREV DISCUSSION... /ISSUED 414 AM EDT SUN APR 24 2016/
SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOW RISING HEIGHTS IN
PROGRESS OVER THE FLORIDA PENINSULA EARLY THIS MORNING. THESE
HEIGHT RISES ARE OCCURRING ON THE BACKSIDE OF A DEPARTING LONGWAVE
TROUGH EXITING INTO THE WESTERN ATLANTIC. THE UPPER PATTERN IS
MUCH MORE ACTIVE OVER THE WESTERN AND CENTRAL CONUS AS A SERIES
OF UPPER DISTURBANCES CONTINUE TO ROTATE IN OFF THE PACIFIC AND
ACROSS THE CONTINENT. THE NORTHERN STREAM DISTURBANCES WILL NOT
HAVE MUCH IMPACT ON OUR WEATHER THROUGH THE FORECAST PERIOD AS
THEIR MAIN IMPACTS REMAIN WELL REMOVED FROM OUR LOCAL AREA. THERE
IS ONE WEAKER SOUTHERN STREAM IMPULSE CURRENTLY OVER NORTHERN
MEXICO THAT WILL BE MAKING SLOW PROGRESS ACROSS THE GULF OF MEXICO
THE NEXT 24-36 HOURS. WILL TALK MORE ABOUT THIS ENERGY AND ITS
POTENTIAL IMPACTS LOCALLY IN THE SHORT TERM DISCUSSION BELOW.
WATER VAPOR SHOWS LITTLE IN THE WAY OF MID/UPPER LEVEL MOISTURE
OVER THE STATE...ALLOWING FOR MOSTLY CLEAR SKIES. THE 24/00Z KTBW
SOUNDING PROFILE CONFIRMED THIS ANALYSIS...WITH A VERY DRY COLUMN
SAMPLED ABOVE 800MB...ALL THE WAY TO THE TROP.
AT THE SURFACE...HIGH PRESSURE CENTERED NEAR THE MID-ATLANTIC
COAST IS RIDGING SOUTHWARD AND BUILDING INTO OUR REGION. THIS
RIDGE WILL BE WITH US FOR THE NEXT SEVERAL DAYS AS IT SLOWLY
MIGRATES SOUTHEASTWARD. AREAS OF FOG HAVE DEVELOPED ACROSS THE
REGION SINCE MIDNIGHT. THIS IS NOT SURPRISING GIVEN THE RISING
HEIGHTS AND LARGE SCALE SUPPRESSION ONGOING OVER-TOP HIGHER LOW
LEVEL MOISTURE. THIS SETUP IS OFTEN FAVORABLE FOR GROUND FOG
DEVELOPMENT. OVERALL DO NOT ANTICIPATE WIDESPREAD DENSE
FOG...HOWEVER A FEW PATCHES OF SIGNIFICANT VISIBILITY REDUCTIONS
ARE POSSIBLE IN NORMALLY FOG PRONE AREAS THROUGH AROUND 13Z.
SHORT TERM (TODAY THROUGH MONDAY)...
AS MENTIONED ABOVE...HEIGHTS ARE RISING OVERHEAD THIS MORNING AS
MID/UPPER LEVEL RIDGING BUILDS OVER THE REGION. AT THE SAME
TIME...SURFACE HIGH PRESSURE IS RIDGING IN FROM THE NORTH/NE.
AFTER EARLY MORNING FOG PATCHES BURN OFF...WILL BE EXPECTING A
MOSTLY SUNNY MORNING WITH TEMPERATURES WARMING TOWARD 80 DEGREES
REGION-WIDE. THIS AFTERNOON...WINDS BEGIN TO SHIFT ONSHORE WITH
SEA-BREEZE DEVELOPMENT NEAR THE COAST...AND THIS WILL PROMOTE THE
DEVELOPMENT OF A FEW-SCT CUMULUS FIELD. GIVEN THE AMOUNT OF DRY
AIR ALOFT AND GENERALLY POOR MID-LEVEL LAPSE RATES...IT SEEMS
CONVECTION ALONG THE SEA- BREEZE WOULD HAVE A SIGNIFICANT
STRUGGLE. HOWEVER...VERY GOOD AGREEMENT AMONG THE CONVECTIVE
ALLOWING GUIDANCE THAT WE WILL SEE ISOLATED- SCT SHOWERS DEVELOP
LATE AFTERNOON/EARLY EVENING ALONG THE I-75 CORRIDOR. THE BEST
POTENTIAL FOR A LATE DAY SHOWER LOOKS TO BE FROM THE TAMPA BAY
AREA SOUTHWARD. SAYING SHOWER...ALTHOUGH AN ISOLATED THUNDERSTORM
CAN NOT BE RULED OUT. IN GENERAL GOING TO HAVE A HARD TIME
DEVELOPING UPDRAFTS DEEP ENOUGH FOR CHARGE SEPARATION AND
LIGHTNING...HOWEVER...A FEW STRONGER UPDRAFTS MAY BE ABLE TO
OVERCOME THE NEGATIVE DRY AIR ALOFT TO SUPPORT A THUNDERSTORM. ANY
SHOWER ACTIVITY (AND IT WILL BE SCT AT BEST) SHOULD HOLD OFF UNTIL
AFTER 20Z. HIGH TEMPERATURES THIS AFTERNOON WILL BE WELL UP INTO
THE 80S FOR MOST SPOTS AWAY FROM THE IMMEDIATE COAST. BEACHES WILL
BE A BIT COOLER WITH THE DEVELOPING ONSHORE FLOW...BUT SHOULD
STILL REACH THE LOWER 80S BEFORE THE SWITCH.
A FEW SHOWERS NEAR THE COAST IN THE EVENING DISSIPATE WITHIN A FEW
HOURS OF SUNSET AND RESULT IN A MOSTLY DRY OVERNIGHT THEREAFTER.
THE DRY CONDITIONS LEAD INTO MONDAY MORNING...WHEN A SIMILAR
FORECAST SCENARIO TO SUNDAY IS EXPECTED. THE ONLY DIFFERENCE WILL
BE THE APPROACH OF A WEAK SOUTHERN STREAM IMPULSE ACROSS THE GULF.
THIS IMPULSE WILL HELP IMPROVE/INCREASE THE MID-LEVEL LAPSE BY
1-2C/KM BY LATER MONDAY AND ALSO ADVECT SOME ADDED MOISTURE INTO
OUR COLUMN. THEREFORE...WOULD ANTICIPATE THE POTENTIAL FOR GREATER
COVERAGE OF SHOWERS OR ISOLATED STORMS AFTER 20Z. IT IS STILL
EARLY IN THE YEAR FOR SIGNIFICANT SEA-BREEZE CONVECTION...SO WILL
NOT GO MUCH ABOVE 30-40% POPS...HOWEVER...WILL NEED TO KEEP AN EYE
ON THE GUIDANCE SINCE THE ENERGY ALOFT WILL CERTAINLY LESSEN THE
CONVECTIVE INHIBITION.
MID/LONG TERM (MONDAY THROUGH NEXT SATURDAY)...
A LATE APRIL WEATHER PATTERN IS CERTAINLY IN PLACE ACROSS WEST
CENTRAL AND SW FLORIDA THIS WEEK AS TEMPERATURES WILL BE WARM WITH
LITTLE TO NO PRECIP EXPECTED. SURFACE HIGH PRESSURE WILL SHIFT OFF
THE EASTERN SEABOARD TO BEGIN THE WEEK AND REMAIN IN PLACE THROUGH
THE FORECAST PERIOD. THIS WILL KEEP OUR WEATHER FAIRLY QUIET
ALTHOUGH WARMER THAN NORMAL. WARM TEMPERATURES AND LIGHT STEERING
FLOW SHOULD ALLOW FOR DAILY SEABREEZES HOWEVER WITH PWAT VALUES IN
THE 1-1.25 INCH RANGE THERE IS NOT GOING TO BE A LOT OF MOISTURE
TO WORK WITH SO WILL KEEP RAIN CHANCES BELOW 20 PERCENT THOUGH THE
PERIOD. IT IS CERTAINLY POSSIBLE THAT MAYBE A STRAY SHALLOW SHOWER
MAY POP UP ALONG THE SEABREEZE BUT MOST OF THE AREA WILL REMAIN
DRY. AFTERNOON HIGH TEMPS ARE EXPECTED IN THE MID TO UPPER 80S FOR
MUCH OF THE WEEK WITH MAYBE A FEW INLAND LOCATIONS REACHING 90 BY
LATE WEEK...COOLER AT THE COAST WITH DAILY SEABREEZES.
AVIATION...
AREAS OF FOG HAVE ALREADY DEVELOPED EARLY THIS MORNING. A PERIOD
OF MVFR/IFR VISIBILITY MAY OCCUR AT ANY TIME THROUGH 13Z...
ESPECIALLY FOR KLAL AND KPGD. ONCE ANY EARLY MORNING FOG PATCHES
BURN OFF...VFR CONDITIONS WILL GENERALLY PREVAIL FOR ALL TERMINALS
THROUGH THE TAF PERIOD. AS THE SEA- BREEZE MOVES INLAND LATE THIS
AFTERNOON... THERE WILL BE A LOW CHANCE FOR A BRIEF SHOWER OR
STORM AT ANY OF THE TERMINALS...MAINLY AFTER 20Z.
MARINE...
HIGH PRESSURE OVER THE WESTERN ATLANTIC WILL RIDGE BACK WESTWARD
OVER THE EASTERN GULF OF MEXICO THROUGH THE MIDDLE OF THE WEEK.
WINDS AND SEAS WILL GENERALLY REMAIN BELOW HEADLINE CRITERIA
THROUGH THE FORECAST PERIOD. EXPECT WINDS TO SHIFT ONSHORE NEAR
THE COAST EACH DAY WITH SEABREEZE FORMATION. A FEW LATE AFTERNOON
OR EVENING THUNDERSTORMS ARE POSSIBLE NEAR THE COAST TODAY AND
AGAIN MONDAY. STORM COVERAGE WILL BE LOW...HOWEVER BOATERS SHOULD
KEEP AN EYE TO THE EAST LATE IN THE DAY AS ANY STORMS THAT DO
DEVELOP OVER LAND WILL TEND TO MIGRATE OFFSHORE.
FIRE WEATHER...
HIGH PRESSURE RIDGES OVER THE STATE THROUGH THE EARLY PORTION OF
THE WEEK. WINDS WILL GENERALLY REMAIN LIGHT...SHIFTING ONSHORE
NEAR THE COAST EACH AFTERNOON. MINIMUM RELATIVE HUMIDITY VALUES
BOTH SUNDAY AND MONDAY AFTERNOONS WILL BRIEFLY APPROACH 35
PERCENT...HOWEVER EXTENDED DURATIONS ARE NOT EXPECTED...AND WINDS
WILL REMAIN BELOW CRITICAL LEVELS...PREVENTING RED FLAG CONDITIONS.
THERE WILL BE A LOW CHANCE FOR A BRIEF LATE AFTERNOON OR EVENING
SHOWER THE NEXT SEVERAL AFTERNOON AS THE SEA-BREEZE PUSHES INLAND.
FOG POTENTIAL...AREAS OF FOG EARLY THIS MORNING WILL BURN OFF WITHIN
A FEW HOURS OF SUNRISE. NO SIGNIFICANT FOG CONCERNS ARE THEN
ANTICIPATED THROUGH MONDAY.
PRELIMINARY POINT TEMPS/POPS...
TPA 84 68 85 68 / 30 30 30 20
FMY 87 67 85 66 / 40 40 30 20
GIF 85 66 84 64 / 10 10 30 10
SRQ 80 67 81 66 / 30 30 20 10
BKV 85 63 84 61 / 20 20 30 10
SPG 84 69 83 69 / 40 40 20 10
TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 84 68 85 68 / 30 30 30 20
FMY 87 67 85 66 / 40 40 30 20
GIF 85 66 84 64 / 10 10 30 10
SRQ 80 67 81 66 / 30 30 20 10
BKV 85 63 84 61 / 20 20 30 10
SPG 84 69 83 69 / 40 40 20 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SHORT TERM/AVIATION/MARINE/FIRE WEATHER...74/WYNN
MID TERM/LONG TERM/DECISION SUPPORT...69/CLOSE
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
616 AM CDT SUN APR 24 2016
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 338 AM CDT SUN APR 24 2016
A closed upper low was located over southern WY per the 08Z water
vapor imagery, and a shortwave was rotating around the base of the
upper low across the CO/NM state line. A surface low pressure system
was gradually deepening over southwest SD. This has allowed
southerly winds to remain up through the morning which continues to
advect moisture from the Gulf of Mexico north. An area of elevated
showers and thunderstorms have developed just west of the forecast
area within an area of isentropic assent.
For this morning, the HRRR/RAP/NAM solutions seem to be handling
the elevated precip fairly well so far. The showers should fall
apart during the mid to late morning hours as the isentropic lift
weakens. The main concern for today remains the potential for severe
storms later in the afternoon and early evening. Models prog the
shortwave currently over the CO/NM state line to be lifting through
north central KS by the late afternoon. Models also show the dryline
setting up across north central KS with increasing low level
convergence along the boundary. Moderate instability around 2000
J/kg may develop just ahead of the dryline as mid level lapse rates
steepen to 7.5 or 8 C/km. With forecast soundings showing a mainly
unidirectional profile and deep layer shear sufficient for supercell
storms, there is the potential for splitting storms and some very
large hail. Initially low level winds remain veered to the SSW and
as a result low level shear parameters are not that impressive for
tornadoes. So it appears that any tornado risk will be dependent on
whether local effects can cause surface winds to back. With a slower
progression to the boundary, Think storm initiation could occur just
to the west of the forecast area between 2 and 5 pm. The forecast
shows increasing POPs into the evening hours anticipating a broken
line of storms to move across northern KS.
Along with the thunderstorms this afternoon and this evening, south
winds should become strong by this afternoon with gusts between 30
and 40 MPH possible. Models show a strong pressure gradient setting
up along the turnpike. Because of this, think there could be a few
hours that sustained winds near 30 MPH with gusts over 40 MPH
through the flint hills and will be issuing a wind advisory for
Morris, Wabaunsee, Lyon, Osage and Coffey counties to account for
this potential.
With the morning showers expected to fall apart by the late morning,
think there should be enough insolation along with decent mixing of
the boundary layer for temps to warm into the upper 70s or around 80
this afternoon. There should be a pretty good gradient in lows temps
as models hang the boundary up across the forecast area. With some
dryer air moving in behind the boundary, lows are forecast to fall
to around 50 across north central KS, while northeast and east
central KS stay in the warm moist air with temps around 60 by Monday
morning.
.LONG TERM...(Monday through Saturday)
Issued at 338 AM CDT SUN APR 24 2016
By Monday morning the frontal boundary is progged to be over far
east central Kansas with any residual showers and thunderstorms
dissipating at this time. There is a slight chance for storms to
redevelop in the afternoon and early evening over east central
Kansas given the weak convergence along the front, however with the
subsident air aloft associated with weak upper ridging, most areas
should remain dry. Dewpoints rise to the upper 50s/lower 60s coupled
with lighter winds around 10 mph, conditions will feel warm and
muggy with highs near 80 degrees.
On Monday evening, the upper trough axis is centered over the
southwest CONUS, with the lee trough beginning to form over eastern
Colorado. The ECMWF and NAM runs respectively continue to develop
light qpf amounts near the boundary (generally south of Interstate
70) with some isentropic lift increasing as moisture return builds
northward. The ECMWF runs have seemed overdone with the amount of
precipitation so have sided closer to the NAM with a slight chance
mention through the morning hours.
A stout EML builds northward into the area as the warm front lifts
dewpoint temps into the lower 60s in the late afternoon Tuesday.
Both the NAM and GFS are signaling higher dewpoints, temperatures
near 80 degrees, therefore the amount of sfc CAPE in the 3000-4000
J/KG range in the late afternoon seems probable. Weakening CIN as
the capping inversion erodes could trigger an isolated storm or two
within the warm sector or just ahead of the dryline across north
central Kansas by late afternoon. Sfc winds back to the southeast at
this time while a 55 kt southerly mid level jet streak enters
central Kansas. Effective bulk shear is fairly similar across the
models at 45 to 50 kts. Low level helicity from 0-1 km shear
increase to near 30 kts by 00Z as the low level jet enhances and the
main upper low pushes into the area. All guidance is pretty robust
in developing scattered convection in the 7 PM to midnight time
frame over northeast Kansas. Optimal low level and mid level shear
parameters, ample instability, and lowering LCL heights pose a
tornado threat, in addition to the large hail and damaging winds.
Only major change to the forecast in this period was to increase
pops to a definite probability after 00Z Wednesday.
As the low pressure system phases over the central plains Wednesday,
speed of the low slows lingering showers and thunderstorms through
portions of the day Wednesday. With the high moisture profiles in
the area and the slowing system, it is possible we could have
isolated flash flooding issues especially for areas near the
Nebraska border. Severe storms are not expected on Wednesday. The
system is progged to exit Wednesday evening as northerly winds and
cool advection increase on Thursday. Thursday may be the only dry
day of the week with highs in the 60s and clearing skies.
The next slow moving upper low builds over the southwest CONUS
before ejecting over the southern and central Plains Friday into
Saturday. Placement of the trough axis still varies from the GFS to
ECMWF, however both are signaling multiple rounds of thunderstorms,
with some potential for strong to severe convection on Saturday
evening.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday Morning)
Issued at 616 AM CDT SUN APR 24 2016
High res models show the elevated showers remaining to the north
of the terminals this morning. Therefore anticipate VFR conditions
prevailing through the afternoon. There is some potential for TS
to impact the terminals this evening. The HRRR/ARW/NMM suggest
convection may only be a scattered so confidence in storms at the
terminals is to low to add a tempo or prevailing group. Although
have based the timing of the VCTS on the HRRR forecast. Have
inserted some MVFR CIGS late tonight as the GFS and NAM show low
levels saturating ahead of the frontal boundary.
&&
.TOP Watches/Warnings/Advisories...
Wind Advisory from noon today to 7 PM CDT this evening for
KSZ037-038-054-055-058.
&&
$$
SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
741 AM EDT SUN APR 24 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 424 AM EDT SUN APR 24 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW A CONFLUENT WNW
FLOW ALF OVER THE UPR LKS BTWN A NRN BRANCH CUTOFF LO OVER NRN
QUEBEC AND A SRN BRANCH FLOW DOMINATING THE CONUS WITH A STRONG
SHRTWV IN THIS FLOW DRIFTING SLOWLY ENEWD THRU WYOMING. THERE IS A
GOOD DEAL OF CLD COVER OVER UPR MI WITH WAA IN TIGHTENING BAROCLINIC
ZN TO THE NE OF H85 WARM FNT STRETCHING FM THE NRN PLAINS INTO WRN
WI...BUT AXIS OF HEAVIEST RA EARLY THIS MRNG STRETCHES FM NCENTRAL
MN ESEWD INTO NCENTRAL WI CLOSER TO THE H85 FNT. THERE ARE MORE SCT
RA SHOWERS DVLPG IN NRN MN WHERE UPR DVGC IN RRQ OF 120KT H3 JET
CORE CENTERED JUST SW OF JAMES BAY IS AIDING LIFT OF MOISTER AIR
SHOWN ON THE 00Z INL RAOB. LINGERING LLVL DRY AIR SHOWN ON THE 00Z
GRB/APX RAOBS THAT IS REPRESENTATIVE OF CONDITIONS OVER THE CWA HAS
SLOWED DOWN THE ARRIVAL OF THIS EXPANDING PCPN AND THE NE PUSH OF
THE RA IN WI CLOSER TO THE H85 WARM FNT. THE AIR IN ONTARIO IS EVEN
DRIER WITH 00Z PWAT AS LO AS 0.14 INCH AT YPL.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/QPF ASSOCIATED
WITH TIGHTENING BAROCLINIC ZN OVER UPR MI UNDER PERSISTENT UPR DVGC
IN RRQ OF H3 JET MAX MOVING ONLY SLOWLY E THRU TNGT. CLOSER APRCH
TNGT OF SHRTWV NOW IN WYOMING WILL INTENSIFY THE DYNAMIC SUPPORT.
CONFIDENCE IS INCRSG THE HEAVIER RA WL FALL NEAR THE WI BORDER...BUT
THERE ARE STILL SOME MODEL INCONSISTENCIES AS TO THE PLACEMENT OF
THE AXIS OF HEAVIER RA RELATED TO POSITION OF SHARPER FGEN AND
IMPACT OF DRY AIR TO THE N.
TDAY...H85 THERMAL GRADIENT/UPR DVGC IN RRQ OF UPR JET CORE TO THE
NE IS FCST TO EXPAND OVER UPR MI TODAY...AND MOST OF THE MODELS
SHIFT AXIS OF HEAVIER PCPN TO THE N ACCORDINGLY. SO WL EXPAND HIER
POPS NE THRU THE CWA EXCEPT OVER THE KEWEENAW...WHICH WL BE CLOSER
TO THE DEEPER DRY AIR JUST TO THE N. HOWEVER...WITH LINGERING LLVL
DRY AIR...FAVOR THE 00Z REGIONAL CNDN MODEL FCST. THIS MODEL SHOWS
THE HIER QPF REMAINING CLOSER TO THE WI BORDER WHERE EVEN THE 00Z
NAM SHOWS MORE PERSISTENT AXIS OF SHARPER H85-7 FGEN/UVV AND WHERE
PWAT IS FCST TO INCRS TO AOA 1 INCH /ABOUT 225 PCT OF NORMAL/. THIS
FCST IS ALSO MORE CONSISTENT WITH LOCATION OF AXIS OF HEAVIER RA FM
NCENTRAL MN INTO NCENTRAL WI EARLY THIS MRNG...THE LOCATION OF WHICH
MAY HINT AT A BNDRY WHICH MAY ACT TO INTERCEPT MSTR INFLOW. WITH THE
CLDS AND RA DVLPG...EXPECT WELL BLO NORMAL MAX TEMPS THAT WL LIKELY
STAY UNDER 40 AT SOME PLACES NEAR LK SUP.
TNGT...WITH SLOW APRCH OF SHRTWV FM THE WSW TNGT...UPR DVGC OVER AND
MSTR TRANSPORT INTO ARE FCST TO INCRS OVERNGT. SO EXPECT HEAVIER RA
TO EXPAND TO THE NE. THE CNDN MODEL STILL SEEMS TO BE ON THE RIGHT
TRACK SHOWING THE AXIS OF HEAVIER PCPN DIMINISHING A BIT WITH THE
SHIFT TO THE NE GIVEN PERSISTENT DRY AIR IN THAT DIRECTION THAT WILL
TEND TO SHARPEN THE NRN EDGE OF THE PCPN/HEAVIER RA. TOTAL RA THRU
12Z MON WL REACH AS MUCH AS 1.50 TO 2.00 INCHES NEAR THE WI BORDER.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 413 AM EDT SUN APR 24 2016
SHORTWAVE TROUGH LIFTING ACROSS THE NORTHERN PLAINS COMBINES WITH
SHARP H85 BAROCLINIC ZONE TO SUPPORT MODERATE PERHAPS HEAVY RAIN
MONDAY MORNING. SINCE STRONGEST H85 TEMP GRADIENT AND ASSOCIATED
FRONTOGENSIS REMAINS OVER SOUTHERN TIER OF UPR MICHIGAN...PERFER
MODEL SOLUTIONS THAT DIMINISH QPF AS IT LIFTS OVER NORTHERN TIER
OF CWA IN THE MORNING. GFS AND GEM-REGIONAL FIT INTO THAT CATEGORY.
QUITE A COOL AND DAMP DAY ON MON NO MATTER THE COVERAGE OF THE RAIN.
EXPECT CHILLY READINGS IN THE MID-UPR 30S NEAR LK SUPERIOR AND
ONLY AROUND 40 ELSEWHERE.
PRIMARY SHORTWAVE TROUGH ARRIVES OVER UPPER GREAT LAKES ON MONDAY
AFTN. JET STREAK ROUNDING BASE OF TROUGH AND SOME ELEVATED
INSTABILITY MAY RESULT IN TSRA POSSIBLY SNEAKING INTO SCNTRL CWA
LATE MONDAY AFTN INTO MONDAY EVENING. DID KEEP MENTION OF TSRA OUT
ATTM AS WITH SFC LOW PASSING BY SOUTH OF UPR MICHIGAN...WOULD EXPECT
BEST CHANCES FOR EVEN ELEVATED TSRA OVER EASTERN WI AND ON FARTHER
SOUTH. ARRIVAL OF THE SHORTWAVE TROUGH SHOULD BRING ANOTHER ROUND OF
RAIN TO MAINLY THE SOUTH AND SOUTH CENTRAL IN THE AFTN. COOLER AIR
WORKS ACROSS UPR MICHIGAN MON EVENING AS THE LOW OVER WI SLIDES
EAST. 1000-500MB/850-700MB THICKNESSES AND NAM/GFS SOUNDINGS
INDICATE POTENTIAL FOR SNOW TO BEGIN MIXING WITH RAIN OVER HIGHER
TERRAIN OF NW AND NCNTRL MON EVENING THEN SWITCH OVER TO SNOW
OVERNIGHT MON NIGHT. SINCE THE ARRIVAL OF THE COLD AIR TIMES OUT
WITH DIMINISHING PRECIPITATION...SNOW AMOUNTS MON NIGHT SHOULD STAY
LESS THAN AN INCH...MAINLY ON GRASSY SURFACES.
AFTER THE RAIN/SNOW TO SNOW MOVES OUT LATE MON NIGHT...LOOKS DRY
THROUGH THE REST OF THE WEEK AND INTO NEXT WEEKEND AS HIGH PRESSURE
BUILDS OVER HUDSON BAY AND PERSISTS. DRY EASTERLY FLOW SHOULD KEEP
UPPER MICHIGAN DRY. WITH THE EAST TO NORTHEAST WIND OFF THE HIGH
COOLEST READINGS DURING THE DAYTIME SHOULD BE NEAR LK SUPERIOR.
TEMPS THERE LIKELY WILL REMAIN SLIGHTLY BELOW NORMAL THROUGH THE
WEEK. INLAND TEMPS AND NEAR LK MICHIGAN SHOULD REACH TOWARD NORMAL
BY MID TO LATE WEEK WITH READINGS IN THE 50S TO NEAR 60 BY LATE IN
THE WEEK. INFLUENCE OF THE DRY HIGH PRESSURE SHOULD ALLOW TEMPS AT
NIGHT AWAY FROM THE GREAT LAKES TO FALL INTO THE 20S TO LOW 30S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 739 AM EDT SUN APR 24 2016
AS AREA OF RA OVERSPREADS UPR MI TODAY...EXPECT VFR CONDITIONS AT
TAF ISSUANCE TIME TO DETERIORATE. SINCE IWD WL BE CLOSEST TO AN
APRCHG WARM FNT/DEEPER MSTR...CIGS WL FALL TO IFR QUICKER THERE AND
BY 18Z. SINCE CMX IS FARTHER N INTO MUCH DRIER AIR...THE ONSET OF
IFR CIGS IS NOT LIKELY TO HAPPEN UNTIL LATER TNGT WHEN AN APRCHG UPR
DISTURBANCE WL BRING A BETTER CHC FOR MORE RA TO OVERCOME THE LLVL
DRY AIR. A MORE UPSLOPE NE FLOW WL BRING ABOUT LIFR CONDITIONS AT
SAW LATER TNGT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 AM EDT SUN APR 24 2016
WITH TIGHTENING PRES GRADIENT BETWEEN HI PRES BUILDING INTO NORTHERN
ONTARIO AND A LO PRES MOVING E FROM THE PLAINS ALONG A STALLED LO
PRES TROUGH TO THE S...EXPECT NE WINDS INCREASING TO 25 TO 30 KTS
THRU MON. THE STRONGEST WINDS WILL BE OVER THE WESTERN LAKE...WHERE
GALES TO 35-40 KTS ARE FORECAST THIS AFTERNOON THRU MON WITH A
COASTLINE CONFIGURATION THAT WILL ACCENTUATE THE NE FLOW. EXPANDED
THE GALE WARNING FOR LSZ162 TO INCLUDE LSZ263 FOR LATE TONIGHT AND
MON. WINDS WILL GRADUALLY DIMINISH MON NIGHT THRU TUE AS A HI PRES
BUILDS INTO THE UPPER LAKES. N TO E WINDS GENERALLY UNDER 20 KTS WILL
THEN PREVAIL ON WED AND THU WITH A HI PRES RIDGE AXIS IN PLACE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 11 AM EDT /10 AM CDT/ THIS MORNING TO 8 PM EDT
/7 PM CDT/ MONDAY FOR LSZ162.
GALE WARNING FROM 5 AM TO 8 PM EDT MONDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...KC
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
654 AM CDT SUN APR 24 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 355 AM CDT Sun Apr 24 2016
The sfc ridge is expected to build further ewd today, allowing sly
winds across the region. An upper ridge is expected to remain in
place today, which will keep precip W of the CWA.
The light FG across ern portions of the CWA shud dissipate by mid-
morning. This area shud also see the most cloud cover, but is still
expected to be only sct coverage. However, high clouds shud cover
the region. Believe these clouds, other than those lower over ern
CWA, will have little impact on temps today. Have trended aoa the
warmer guidance across the region.
Tilly
.LONG TERM... (Tonight through Saturday)
Issued at 355 AM CDT Sun Apr 24 2016
An omega block will dominate Canada and the northern CONUS thru this
week, with upper longwave TROFs on the west and east coasts and the
RIDGE component over the Plains. A series of strong Pacific storms
will run just south of this blocking pattern, being dropped off from
the west coast TROF and being picked up by the east coast TROF a few
days later, with an overall track to the E-NE thru our region. Model
progs show that each successive storm system will track a bit
further south than its predecessor.
The first storm system will track to our north late tonight and into
Monday, and will be just a glancing blow to our region as a result,
with what forms mostly upstream initially to our northwest working
its way in late tonight as it weakens with a possible low level
boundary setting up for additional development further southeast
during the day on Monday.
In the wake of this first storm system, a cold front will drop down
late Monday night into Tuesday and will maintain a low chance for
rain. Severe storm chances up until this point look to be low.
The second Pacific storm system will be more of a direct hit as it
will initially correspond well with the surface frontal boundary
buckling north as a warm front late Tuesday night into Wednesday
morning. This should result in elevated storms, with hail as their
primary severe threat during that time.
Heading into Wednesday afternoon and evening, it will depend heavily
on how far north the front gets. Models continue to skiddishly
track the frontal boundary a tad further south than where they were
progging it 24hrs prior, but the bottom line still remains nearly
the same for now, with a strong shear and unstable environment with
a low level boundary for severe storm formation potential, including
tornadoes.
Things dry out briefly for late in the work week before the third
storm system approaches from the west for the upcoming weekend and
rain chances ramp up again. But with this storm system expected to
track the furthest south, this next episode of rain could very well
be mostly showers with imbedded storms if this track holds, with any
severe potential remaining well to the south.
Otherwise, the default RIDGE setup in our part of the CONUS will
ensure that temps remain at or above average throughout the period.
TES
&&
.AVIATION... (For the 12z TAFs through 12z Monday Morning)
Issued at 640 AM CDT Sun Apr 24 2016
Winds will become sly and increase this morning with gusts to
around 20 kts possible, mainly at UIN/COU. Isod to sct TSRA are
possible late tonight, possibly impacting UIN/COU. Given the isod
nature of these storms, have held off mentioning in the TAF attm.
A bkn cloud deck will also move into the region late tonight, but
is expected to remain VFR.
Specifics for KSTL: Once current FG dissipates, VFR and dry
conditions expected thru the TAF period.
Tilly
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
654 AM CDT SUN APR 24 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 355 AM CDT Sun Apr 24 2016
The sfc ridge is expected to build further ewd today, allowing sly
winds across the region. An upper ridge is expected to remain in
place today, which will keep precip W of the CWA.
The light FG across ern portions of the CWA shud dissipate by mid-
morning. This area shud also see the most cloud cover, but is still
expected to be only sct coverage. However, high clouds shud cover
the region. Believe these clouds, other than those lower over ern
CWA, will have little impact on temps today. Have trended aoa the
warmer guidance across the region.
Tilly
.LONG TERM... (Tonight through Saturday)
Issued at 355 AM CDT Sun Apr 24 2016
An omega block will dominate Canada and the northern CONUS thru this
week, with upper longwave TROFs on the west and east coasts and the
RIDGE component over the Plains. A series of strong Pacific storms
will run just south of this blocking pattern, being dropped off from
the west coast TROF and being picked up by the east coast TROF a few
days later, with an overall track to the E-NE thru our region. Model
progs show that each successive storm system will track a bit
further south than its predecessor.
The first storm system will track to our north late tonight and into
Monday, and will be just a glancing blow to our region as a result,
with what forms mostly upstream initially to our northwest working
its way in late tonight as it weakens with a possible low level
boundary setting up for additional development further southeast
during the day on Monday.
In the wake of this first storm system, a cold front will drop down
late Monday night into Tuesday and will maintain a low chance for
rain. Severe storm chances up until this point look to be low.
The second Pacific storm system will be more of a direct hit as it
will initially correspond well with the surface frontal boundary
buckling north as a warm front late Tuesday night into Wednesday
morning. This should result in elevated storms, with hail as their
primary severe threat during that time.
Heading into Wednesday afternoon and evening, it will depend heavily
on how far north the front gets. Models continue to skiddishly
track the frontal boundary a tad further south than where they were
progging it 24hrs prior, but the bottom line still remains nearly
the same for now, with a strong shear and unstable environment with
a low level boundary for severe storm formation potential, including
tornadoes.
Things dry out briefly for late in the work week before the third
storm system approaches from the west for the upcoming weekend and
rain chances ramp up again. But with this storm system expected to
track the furthest south, this next episode of rain could very well
be mostly showers with imbedded storms if this track holds, with any
severe potential remaining well to the south.
Otherwise, the default RIDGE setup in our part of the CONUS will
ensure that temps remain at or above average throughout the period.
TES
&&
.AVIATION... (For the 12z TAFs through 12z Monday Morning)
Issued at 640 AM CDT Sun Apr 24 2016
Winds will become sly and increase this morning with gusts to
around 20 kts possible, mainly at UIN/COU. Isod to sct TSRA are
possible late tonight, possibly impacting UIN/COU. Given the isod
nature of these storms, have held off mentioning in the TAF attm.
A bkn cloud deck will also move into the region late tonight, but
is expected to remain VFR.
Specifics for KSTL: Once current FG dissipates, VFR and dry
conditions expected thru the TAF period.
Tilly
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
[top]
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
638 AM CDT SUN APR 24 2016
.Discussion...
Issued at 417 AM CDT SUN APR 24 2016
Today - Tonight:
The first in a series of upper level systems will bring scattered
convection to at least the northwest half of the CWA starting late
this afternoon. A closed upper low now over WY is progged to track
east and reach the central SD/NE border by late afternoon. A
nocturnal low-level jet over the Central Plains and modest
isentropic ascent are currently aiding a narrow band of elevated
convection from central KS into south central NE. This activity is
expected to lift northeast and possibly graze the northwest tip of
MO this morning before dissipating.
Several additional features will generate strong/severe convection
from western OK through central KS and into far northwest MO. A
dryline will set up from central KS through far western OK this
afternoon while a cold front swings southeast from under the WY
system. As a h7 vorticity max/lobe emerges from under the WY system
and ejects northeast across KS scattered surface-based convection
will form along the KS/OK portion of the dryline. In addition storms
will form over southeast NE/northeast KS where a weak boundary left
by this mornings convection or a pre-frontal convergence zone lies.
The NE/KS convection should affect the northwest 1/3 of the CWA late
this afternoon and early evening. Moderate instability around 1500
J/kg with 30kt 0-6km shear may be sufficient to support a few
marginally severe storms. The primary threat will be large hail. The
severe threat will last several hours ending a few hours after
sunset as the storms weaken as they move east into a less favorable
environment. Coverage and intensity will gradually decrease with
time such that most of the convection will have dissipated by the
pre-dawn hours of Monday morning.
The severe storms which form along the KS/OK dryline may never reach
the CWA as they will weaken and tend to decrease in coverage as they
lift northeast and off the dryline. Accept the model trends in
slowing the arrival of the convection into the CWA as well as
decreasing it in coverage. So, have lowered PoPs for all but the
northwest 1/3 of the CWA as well as limit the QPF.
Monday - Saturday:
As noted in yesterday`s discussion this will be a very active period
with several additional periods of strong/possibly severe convection
as well as the potential for heavy rainfall Tuesday night/Wednesday.
While Monday looks relatively quiet isolated convection is still
possible as the earlier mentioned cold front stalls over the CWA and
around 1000 J/kg of instability will be available. Increasing mid
level heights and the lack of an upper level feature should greatly
limit convection.
By Tuesday the next closed upper system will move out of the Central
High Plains. This system will be much larger with a better defined
negatively tilted shortwave ejecting northeast across KS. With
surface dewpoints likely well into the 60s advecting into the region
there will be ample instability, in excess of 2500 J/kg, to supply
the needed energy for severe convection Tuesday evening. Will need
to keep a close eye on where the warm front will be as it will be a
primary focus for severe storm development. However, the shear will
be near the lower end of the threshold with 0-6km shear in the 25-
30kt range. Heavy rainfall will also be a concern Tuesday
night/Wednesday as precipitable water values between 1.25 and 1.5
inches are near the 99% percentile.
Should see at least a one day break in the rain on Thursday,
possibly carrying over into the first part of Friday before the next
upper trough sends the first wave of warm air advection convection
into the CWA by Friday evening. Timing differences between the ECMWF
and the GFS by the end of the week requires more of a broadbrush
approach on rain chances. Even then PoPs will be rather high this
far out. Should we get as much rain as the models are advertising in
the upcoming week we should eliminate the yearly shortage in
precipitation.
&&
.Aviation...(For the 12Z TAFS through 12Z Monday Morning)
Issued at 632 AM CDT SUN APR 24 2016
Scattered elevated showers will cross far northwest MO through 14z
before lifting into IA. Otherwise VFR conditions with strong and
gusty southerly winds developing by mid morning and lasting well into
the evening hours.
Expect to see scattered convection to reform over southeast
NE/northeast KS by late afternoon and track across northwest MO. A
few strong/marginally severe storms possible over this area towards
sunset and lasting into mid evening. Other scattered convection is
possible over east central KS and west central MO after 00z but with
the activity weakening quickly by mid evening. Most of the convection
will decrease greatly in coverage and intensity after midnight as it
heads towards northeast MO.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...MJ
Aviation...MJ
[top]
Area Forecast Discussion
National Weather Service Springfield MO
607 AM CDT SUN APR 24 2016
.SHORT TERM...(Today and tonight)
Issued at 343 AM CDT Sun Apr 24 2016
An upper level ridge remains over the central U.S. early this
morning along with a warm air mass. Early morning temperatures are
currently in the upper 50s to lower 60s. Temperatures will not
drop much more early this morning with lows in the middle 50s to
around 60 occurring.
An upper level low is currently over Wyoming early this morning,
and will track to the east and opening up today into tonight. This
will start to push the ridge to the east today. Surface low
pressure has developed ahead of the upper level low across the
plains. The pressure gradient will tighten across the region today
as the low tracks east. Temperatures will be very similar to those
that were observed on Saturday with highs in the upper 70s to the
lower 80s. There will be few more clouds today than yesterday but
still plenty of sunshine will occur. Southerly winds will increase
and be gusty today ahead of the approaching system and gusts over
30 mph will occur at times mainly along and west of Hwy 65 this
afternoon.
A cold front associated with the surface low will track east
across portions of central and eastern Nebraska and Kansas today
into tonight. This evening Thunderstorms will develop along the
front to the west and northwest of the forecast area. The front
will remain to the west and north of the area and not move into
the area overnight. Storms will likely move off the front but
instability will be weaker the farther to the east and with the
better lift remaining west of the area storms will weaken as they
push into the area. A few storms may make it into the area before
dissipating but most locations should remain dry.
.LONG TERM...(Monday through Saturday)
Issued at 343 AM CDT Sun Apr 24 2016
The front is expected to remain north of the area on Monday as the
upper level trough and surface low push off to the east. Shortwave
upper level ridging will build over the area on Monday. Can not
rule out an isolated shower/rumble of thunder mainly in the
morning hours as isentropic lift spreads across the area ahead of
the ridge, but expect most location to remain dry during the day
on Monday.
Isentropic lift will again develop, mainly over the extreme
southeastern Kansas and far southwestern Missouri Monday night
into Tuesday morning. Instability will start to develop across
the area as Gulf moisture spread north, but a cap will also develop
across the area. The cap does weaken some for an elevated storm,
but it does not go completely away. Did include a chance for
thunderstorms to develop across the western portions of the
forecast area to account for this. Instability for an elevated
storm will be limited so not expecting strong to severe storms at
this time.
An upper level trough will lift across the plains on Tuesday then
to the north of the area on Wednesday. Instability will increase
across the region ahead of this system but so will the cap. So,
besides a few morning storms mentioned above, think the cap will
keep much of the afternoon hours dry. Surface low pressure will
develop across the central Plains and connect with the front that
will stall to the north of the area, with it being a warm front.
As the Low level jet increases Tuesday evening storms are expected
to develop along and just north of the warm front, at this time
the front is expected to remain north of the area and these storms
should too.
As the low lifts to the northeast a cold front will move east
across central Kansas and central Oklahoma late Tuesday afternoon
into Tuesday evening. The cap will weaken enough for storms to
develop along and ahead of the front. They should be able to move
off the front as the front only slowly moves east, resulting in
the potential for supercells. The front will not push east into
the area Tuesday night, but cold pools from the storms could
congeal and keep the storms going to the east, in more of a line
or line segments, pushing into and across the area Tuesday night
into Wednesday morning. Instability will be weaker given the
overnight timing, but will remain strong enough to support a
severe risk across the area Tuesday night and Wednesday. Low level
shear will increase with the approach of the storm system, so all
modes of severe weather will be possible, through large hail and
damaging straight line winds will be the main risk. The front will
push across the region Wednesday with the storms/rain chances
ending Wednesday evening.
Thursday will be a dry day then yet another storm system will
track into and across the region Friday into the weekend bringing
additional rounds for showers and thunderstorms to the region.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
Issued at 558 AM CDT Sun Apr 24 2016
Breezy conditions are expected from late morning through the
afternoon as the pressure gradient increases over the region ahead
of an area of low pressure. Will see wind gusts today at JLN/SGF
at around 25 to 28 kts at times. Still expecting only VFR ceilings
at this time through the terminal forecast.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...Lindenberg
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
417 AM CDT SUN APR 24 2016
.Discussion...
Issued at 417 AM CDT SUN APR 24 2016
Today - Tonight:
The first in a series of upper level systems will bring scattered
convection to at least the northwest half of the CWA starting late
this afternoon. A closed upper low now over WY is progged to track
east and reach the central SD/NE border by late afternoon. A
nocturnal low-level jet over the Central Plains and modest
isentropic ascent are currently aiding a narrow band of elevated
convection from central KS into south central NE. This activity is
expected to lift northeast and possibly graze the northwest tip of
MO this morning before dissipating.
Several additional features will generate strong/severe convection
from western OK through central KS and into far northwest MO. A
dryline will set up from central KS through far western OK this
afternoon while a cold front swings southeast from under the WY
system. As a h7 vorticity max/lobe emerges from under the WY system
and ejects northeast across KS scattered surface-based convection
will form along the KS/OK portion of the dryline. In addition storms
will form over southeast NE/northeast KS where a weak boundary left
by this mornings convection or a pre-frontal convergence zone lies.
The NE/KS convection should affect the northwest 1/3 of the CWA late
this afternoon and early evening. Moderate instability around 1500
J/kg with 30kt 0-6km shear may be sufficient to support a few
marginally severe storms. The primary threat will be large hail. The
severe threat will last several hours ending a few hours after
sunset as the storms weaken as they move east into a less favorable
environment. Coverage and intensity will gradually decrease with
time such that most of the convection will have dissipated by the
pre-dawn hours of Monday morning.
The severe storms which form along the KS/OK dryline may never reach
the CWA as they will weaken and tend to decrease in coverage as they
lift northeast and off the dryline. Accept the model trends in
slowing the arrival of the convection into the CWA as well as
decreasing it in coverage. So, have lowered PoPs for all but the
northwest 1/3 of the CWA as well as limit the QPF.
Monday - Saturday:
As noted in yesterday`s discussion this will be a very active period
with several additional periods of strong/possibly severe convection
as well as the potential for heavy rainfall Tuesday night/Wednesday.
While Monday looks relatively quiet isolated convection is still
possible as the earlier mentioned cold front stalls over the CWA and
around 1000 J/kg of instability will be available. Increasing mid
level heights and the lack of an upper level feature should greatly
limit convection.
By Tuesday the next closed upper system will move out of the Central
High Plains. This system will be much larger with a better defined
negatively tilted shortwave ejecting northeast across KS. With
surface dewpoints likely well into the 60s advecting into the region
there will be ample instability, in excess of 2500 J/kg, to supply
the needed energy for severe convection Tuesday evening. Will need
to keep a close eye on where the warm front will be as it will be a
primary focus for severe storm development. However, the shear will
be near the lower end of the threshold with 0-6km shear in the 25-
30kt range. Heavy rainfall will also be a concern Tuesday
night/Wednesday as precipitable water values between 1.25 and 1.5
inches are near the 99% percentile.
Should see at least a one day break in the rain on Thursday,
possibly carrying over into the first part of Friday before the next
upper trough sends the first wave of warm air advection convection
into the CWA by Friday evening. Timing differences between the ECMWF
and the GFS by the end of the week requires more of a broadbrush
approach on rain chances. Even then PoPs will be rather high this
far out. Should we get as much rain as the models are advertising in
the upcoming week we should eliminate the yearly shortage in
precipitation.
&&
.Aviation...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1046 PM CDT SAT APR 23 2016
VFR conditions expected through much of the fcst period. Latest
model runs suggesting the bulk of thunderstorm activity will remain
west of the forecast area. Cannot rule out some isolated convection
holding itself together as it moves east off the dryline in central
Kansas...but activity will be moving into a more and more unfavorable
environment with further eastward progress. In any event...have
inserted a VCTS mention for STJ...and later updates can address the
KC terminals if trends begin to change. The other main concern
remains the likelihood for LLWS early this morning thanks to a strong
southwesterly low-level jet...and have maintained mention for all
terminals with the 06z package. Meanwhile...southerly winds of 10-15
kts overnight will increase after 16z on Sunday with gusts up to 30
kts possible during the afternoon hours.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...MJ
Aviation...32
Area Forecast Discussion
National Weather Service Saint Louis MO
355 AM CDT SUN APR 24 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 355 AM CDT Sun Apr 24 2016
The sfc ridge is expected to build further ewd today, allowing sly
winds across the region. An upper ridge is expected to remain in
place today, which will keep precip W of the CWA.
The light FG across ern portions of the CWA shud dissipate by mid-
morning. This area shud also see the most cloud cover, but is still
expected to be only sct coverage. However, high clouds shud cover
the region. Believe these clouds, other than those lower over ern
CWA, will have little impact on temps today. Have trended aoa the
warmer guidance across the region.
Tilly
.LONG TERM... (Tonight through Saturday)
Issued at 355 AM CDT Sun Apr 24 2016
An omega block will dominate Canada and the northern CONUS thru this
week, with upper longwave TROFs on the west and east coasts and the
RIDGE component over the Plains. A series of strong Pacific storms
will run just south of this blocking pattern, being dropped off from
the west coast TROF and being picked up by the east coast TROF a few
days later, with an overall track to the E-NE thru our region. Model
progs show that each successive storm system will track a bit
further south than its predecessor.
The first storm system will track to our north late tonight and into
Monday, and will be just a glancing blow to our region as a result,
with what forms mostly upstream initially to our northwest working
its way in late tonight as it weakens with a possible low level
boundary setting up for additional development further southeast
during the day on Monday.
In the wake of this first storm system, a cold front will drop down
late Monday night into Tuesday and will maintain a low chance for
rain. Severe storm chances up until this point look to be low.
The second Pacific storm system will be more of a direct hit as it
will initially correspond well with the surface frontal boundary
buckling north as a warm front late Tuesday night into Wednesday
morning. This should result in elevated storms, with hail as their
primary severe threat during that time.
Heading into Wednesday afternoon and evening, it will depend heavily
on how far north the front gets. Models continue to skiddishly
track the frontal boundary a tad further south than where they were
progging it 24hrs prior, but the bottom line still remains nearly
the same for now, with a strong shear and unstable environment with
a low level boundary for severe storm formation potential, including
tornadoes.
Things dry out briefly for late in the work week before the third
storm system approaches from the west for the upcoming weekend and
rain chances ramp up again. But with this storm system expected to
track the furthest south, this next episode of rain could very well
be mostly showers with imbedded storms if this track holds, with any
severe potential remaining well to the south.
Otherwise, the default RIDGE setup in our part of the CONUS will
ensure that temps remain at or above average throughout the period.
TES
&&
.AVIATION... (For the 06z TAFs through 06z Sunday Night)
Issued at 1152 PM CDT Sat Apr 23 2016
Dry and VFR conditions are still expected at the terminals through
the TAF period. There may be some patchy fog late tonight and
early Sunday over southern Illinois and southeast Missouri. Low
level wind shear is still possible at KUIN and KCOU between 09-15Z
as a 35-40kt low level jet sets up between 1000-2000 feet. Still
expect gusts over 20kts during the late morning and afternoon
hours that will decrease slightly after sunset.
Specifics for KSTL:
Dry and VFR conditions are expected through the TAF period. Gusts
above 20 kts are possible after 18Z on Sunday afternoon.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Springfield MO
347 AM CDT SUN APR 24 2016
.SHORT TERM...(Today and tonight)
Issued at 343 AM CDT Sun Apr 24 2016
An upper level ridge remains over the central U.S. early this
morning along with a warm air mass. Early morning temperatures are
currently in the upper 50s to lower 60s. Temperatures will not
drop much more early this morning with lows in the middle 50s to
around 60 occurring.
An upper level low is currently over Wyoming early this morning,
and will track to the east and opening up today into tonight. This
will start to push the ridge to the east today. Surface low
pressure has developed ahead of the upper level low across the
plains. The pressure gradient will tighten across the region today
as the low tracks east. Temperatures will be very similar to those
that were observed on Saturday with highs in the upper 70s to the
lower 80s. There will be few more clouds today than yesterday but
still plenty of sunshine will occur. Southerly winds will increase
and be gusty today ahead of the approaching system and gusts over
30 mph will occur at times mainly along and west of Hwy 65 this
afternoon.
A cold front associated with the surface low will track east
across portions of central and eastern Nebraska and Kansas today
into tonight. This evening Thunderstorms will develop along the
front to the west and northwest of the forecast area. The front
will remain to the west and north of the area and not move into
the area overnight. Storms will likely move off the front but
instability will be weaker the farther to the east and with the
better lift remaining west of the area storms will weaken as they
push into the area. A few storms may make it into the area before
dissipating but most locations should remain dry.
.LONG TERM...(Monday through Saturday)
Issued at 343 AM CDT Sun Apr 24 2016
The front is expected to remain north of the area on Monday as the
upper level trough and surface low push off to the east. Shortwave
upper level ridging will build over the area on Monday. Can not
rule out an isolated shower/rumble of thunder mainly in the
morning hours as isentropic lift spreads across the area ahead of
the ridge, but expect most location to remain dry during the day
on Monday.
Isentropic lift will again develop, mainly over the extreme
southeastern Kansas and far southwestern Missouri Monday night
into Tuesday morning. Instability will start to develop across
the area as Gulf moisture spread north, but a cap will also develop
across the area. The cap does weaken some for an elevated storm,
but it does not go completely away. Did include a chance for
thunderstorms to develop across the western portions of the
forecast area to account for this. Instability for an elevated
storm will be limited so not expecting strong to severe storms at
this time.
An upper level trough will lift across the plains on Tuesday then
to the north of the area on Wednesday. Instability will increase
across the region ahead of this system but so will the cap. So,
besides a few morning storms mentioned above, think the cap will
keep much of the afternoon hours dry. Surface low pressure will
develop across the central Plains and connect with the front that
will stall to the north of the area, with it being a warm front.
As the Low level jet increases Tuesday evening storms are expected
to develop along and just north of the warm front, at this time
the front is expected to remain north of the area and these storms
should too.
As the low lifts to the northeast a cold front will move east
across central Kansas and central Oklahoma late Tuesday afternoon
into Tuesday evening. The cap will weaken enough for storms to
develop along and ahead of the front. They should be able to move
off the front as the front only slowly moves east, resulting in
the potential for supercells. The front will not push east into
the area Tuesday night, but cold pools from the storms could
congeal and keep the storms going to the east, in more of a line
or line segments, pushing into and across the area Tuesday night
into Wednesday morning. Instability will be weaker given the
overnight timing, but will remain strong enough to support a
severe risk across the area Tuesday night and Wednesday. Low level
shear will increase with the approach of the storm system, so all
modes of severe weather will be possible, through large hail and
damaging straight line winds will be the main risk. The front will
push across the region Wednesday with the storms/rain chances
ending Wednesday evening.
Thursday will be a dry day then yet another storm system will
track into and across the region Friday into the weekend bringing
additional rounds for showers and thunderstorms to the region.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1144 PM CDT Sat Apr 23 2016
For the KSGF/KJLN/KBBG tafs: VFR conditions are expected with
increasing south to southeast winds. Low pressure will move into
the Plains with an increasing pressure gradient and sfc winds by
15z. High resolution models support sustained 15-20kt winds with
higher gusts.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...DSA
Area Forecast Discussion
National Weather Service Springfield MO
1158 PM CDT SAT APR 23 2016
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1144 PM CDT Sat Apr 23 2016
For the KSGF/KJLN/KBBG tafs: VFR conditions are expected with
increasing south to southeast winds. Low pressure will move into
the Plains with an increasing pressure gradient and sfc winds by
15z. High resolution models support sustained 15-20kt winds with
higher gusts.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...DSA
Area Forecast Discussion
National Weather Service Springfield MO
1158 PM CDT SAT APR 23 2016
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1144 PM CDT Sat Apr 23 2016
For the KSGF/KJLN/KBBG tafs: VFR conditions are expected with
increasing south to southeast winds. Low pressure will move into
the Plains with an increasing pressure gradient and sfc winds by
15z. High resolution models support sustained 15-20kt winds with
higher gusts.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...DSA
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1152 PM CDT SAT APR 23 2016
.UPDATE...
Issued at 921 PM CDT Sat Apr 23 2016
Going dry forecast the rest of the night still looks good as upper
ridge moves over the area allowing for only a few high clouds to
drift across the area. Still may be some patchy fog tonight, but
think this will be held in check by the wind which should stay up
tonight as the pressure gradient continues to tighten. Only made
minor adjustments to lows based on going temperature trends.
Britt
&&
.SHORT TERM... (Through Late Tonight)
Issued at 255 PM CDT Sat Apr 23 2016
Surface ridge extending from MI southwest into eastern MO will move
eastward. The stratus clouds across southeast IL should continue to
dissipate late this afternoon. Few-scattered diurnal cumulus
clouds, especially across parts of northeast and central MO will
dissipate early this evening with the loss of daytime heating.
Mainly just a little high level cloudiness tonight. Lows tonight
will be warmer than the previous night, mainly due to southeast
surface winds on the backside of the surface ridge. The warmest
temperatures will be across central MO with the coolest temperatures
in southwest IL. Lows tonight will be about 5 to 10 degrees above
normal for late April.
GKS
.LONG TERM... (Sunday through Next Saturday)
Issued at 255 PM CDT Sat Apr 23 2016
Dry and warmer weather to persist on Sunday, but will see an
increase in high clouds as next weather system approaches region.
With gusty south winds will see highs in the upper 70s to low 80s.
Sunday night rain chances to approach region, but models are a bit
slower with onset, so lowered pops just a bit. Then Monday through
Tuesday, frontal boundary to slowly slide south through area with
mainly scattered showers and thunderstorms. Front to stall out
across southern Missouri on Tuesday. Highs will be in the upper 70s
to low 80s on Monday, then dip down into the low 70s to low 80s
Tuesday and Wednesday.
Decent instability north of front Tuesday night, so could see
elevated activity develop and slide along boundary on nose of decent
low level jet. Large hail would be the main threat with this round
of storms.
Models are still indicating decent instability, CAPES in excess of
1500 J/kg and shear with system Wednesday afternoon, Wednesday night
as warm front lifts north through forecast area. All of this still
points to our first real potential severe weather day this spring,
but a lot can happen in 5 days. Stay tuned to further updates.
With everything a bit slower, main cold front to slide through early
on Thursday with precipitation tapering off to just slight chance
pops through Friday. Then extended models showing next system
lifting northeast towards forecast area Friday night and Saturday
with increasing chances of showers and thunderstorms once again.
Once system exits region on Thursday, will see precipitation taper
off. Even though it will be a bit cooler Thursday, highs will still
be a bit above normal in the mid 60s to upper 70s. Extended models
beginning to indicate another system approaching region on Friday,
but timing is hard to pin down. So for now kept slight chance pops.
Byrd
&&
.AVIATION... (For the 06z TAFs through 06z Sunday Night)
Issued at 1152 PM CDT Sat Apr 23 2016
Dry and VFR conditions are still expected at the terminals through
the TAF period. There may be some patchy fog late tonight and
early Sunday over southern Illinois and southeast Missouri. Low
level wind shear is still possible at KUIN and KCOU between 09-15Z
as a 35-40kt low level jet sets up between 1000-2000 feet. Still
expect gusts over 20kts during the late morning and afternoon
hours that will decrease slightly after sunset.
Specifics for KSTL:
Dry and VFR conditions are expected through the TAF period. Gusts
above 20 kts are possible after 18Z on Sunday afternoon.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1047 PM CDT SAT APR 23 2016
.Short Term...(This Evening through Monday Night)
Issued at 309 PM CDT SAT APR 23 2016
Short Term (Tonight through Monday night):
The main concern in the short term will be the potential for a few
strong and isolated severe storms on Sunday evening into Sunday
night. Tonight, however will be much less interesting and quite
pleasant as modest southerly winds will hold temperatures in the mid
50s to lower 60s. The system, an upper level trough, that will bring
thunderstorms to the area Sunday will move from western Wyoming to
near the WY/SD/NE by Saturday night. This will force a cold front into
the western Plains. Thunderstorms will develop along this front
tonight across western Kansas. This storms will progress across
Kansas overnight enhanced by a 50-60kt SSWly nocturnal LLJ. By early
Sunday morning the LLJ will veer to the southwest and storms will
begin to approach northeastern KS and northwestern MO. However,
these storms will be weakening as they approach and there may just
be a few isolated storms or residual shower to make it into the
extreme NW CWA Sunday morning. However, by Sunday afternoon, a dry
line will exist across central Kansas with the attendant cold front
lagging to the west across the western High Plains. Thunderstorms
are expected to develop out ahead of the cold front across central
Kansas during the afternoon and move eastward. These storms will
have the potential to be strong with perhaps isolated severe storms
possible mainly across northwestern MO/northeastern KS where
dewpoints will be near 60 degrees, modest instability of 500-
800J/kg, and steep mid-level lapse rates will exist. However, shear
is not impressive and as previously mentioned instability is merely
modest. Consequently, strong storms will be possible and perhaps
even a marginally severe storm capable of producing large hail or
damaging winds. Storms will weaken Sunday night as storms move into
a more stable environment and the upper level trough continues to
weak as it moves into the Upper Midwest. On Monday, the cold front
associated with the upper level system will sag through the area.
However, will little forcing the front will sag through the area
with little activity expected. The best chance for storms would
occur head of the front where modest instability will reside. Monday
night the cold front will sink south of the area and become
stationary. A few thunderstorms may develop north of the stationary
boundary Monday as a SW 40kt LLJ overrides the boundary. These
thunderstorms may affect the southern CWA depending on the location
of the front.
.Long Term...(Tuesday through Saturday)
Issued at 309 PM CDT SAT APR 23 2016
Tuesday evening and Wednesday will bring another round of showers
and possibly severe thunderstorms to the CWA. The most recent NAM
and GFS runs show Tuesday morning and early afternoon warm and humid
with precipitation mainly staying just south of the WFO. A negatively
tilted low pressure trough stations itself over eastern CO/western KS
Tuesday afternoon. A cold front will move east through Kansas
Wednesday afternoon, and an associated warm front will be located E-W
through our forecast area late Tuesday bringing low- level moisture
with it. Dew point temperatures will range from low 50s north of the
front spreading south to the mid-60s. We will also have decent
instability and shear with CAPE values around 1000-2000 J/kg and
30-50 kt 0-6 km bulk shear. A combination of high CAPE and shear may
lead to potentially severe thunderstorms ahead of the cold front. The
development and location of severe weather will depend on the timing
of convection and the frontal passage, which will become more clear
as we get closer to the event. For now, the GFS and Euro models show
precipitation starting in eastern KS and moving east through the WFO
late Tuesday night through Wednesday morning. Convection could
continue throughout Wednesday as CAPE values are expected to stay
above 1000 J/kg throughout Wednesday afternoon.
High temperatures will continue to be in the mid 70s through
Wednesday, but will drop to the mid-high 60s for Thursday and Friday
after the cold front passes. Low temperatures will drop Thursday and
Friday mornings to the high 40s to low 50s. Thursday is expected to
be dry before another upper low system may cause more precipitation
late Friday into Saturday.
&&
.Aviation...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1046 PM CDT SAT APR 23 2016
VFR conditions expected through much of the fcst period. Latest
model runs suggesting the bulk of thunderstorm activity will remain
west of the forecast area. Cannot rule out some isolated convection
holding itself together as it moves east off the dryline in central
Kansas...but activity will be moving into a more and more unfavorable
environment with further eastward progress. In any event...have
inserted a VCTS mention for STJ...and later updates can address the
KC terminals if trends begin to change. The other main concern
remains the likelihood for LLWS early this morning thanks to a strong
southwesterly low-level jet...and have maintained mention for all
terminals with the 06z package. Meanwhile...southerly winds of 10-15
kts overnight will increase after 16z on Sunday with gusts up to 30
kts possible during the afternoon hours.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Short Term...73
Long Term...Chandler/CDB
Aviation...32
Area Forecast Discussion...Updated
National Weather Service Saint Louis MO
921 PM CDT SAT APR 23 2016
.UPDATE...
Issued at 921 PM CDT Sat Apr 23 2016
Going dry forecast the rest of the night still looks good as upper
ridge moves over the area allowing for only a few high clouds to
drift across the area. Still may be some patchy fog tonight, but
think this will be held in check by the wind which should stay up
tonight as the pressure gradient continues to tighten. Only made
minor adjustments to lows based on going temperature trends.
Britt
&&
.SHORT TERM... (Through Late Tonight)
Issued at 255 PM CDT Sat Apr 23 2016
Surface ridge extending from MI southwest into eastern MO will move
eastward. The stratus clouds across southeast IL should continue to
dissipate late this afternoon. Few-scattered diurnal cumulus
clouds, especially across parts of northeast and central MO will
dissipate early this evening with the loss of daytime heating.
Mainly just a little high level cloudiness tonight. Lows tonight
will be warmer than the previous night, mainly due to southeast
surface winds on the backside of the surface ridge. The warmest
temperatures will be across central MO with the coolest temperatures
in southwest IL. Lows tonight will be about 5 to 10 degrees above
normal for late April.
GKS
.LONG TERM... (Sunday through Next Saturday)
Issued at 255 PM CDT Sat Apr 23 2016
Dry and warmer weather to persist on Sunday, but will see an
increase in high clouds as next weather system approaches region.
With gusty south winds will see highs in the upper 70s to low 80s.
Sunday night rain chances to approach region, but models are a bit
slower with onset, so lowered pops just a bit. Then Monday through
Tuesday, frontal boundary to slowly slide south through area with
mainly scattered showers and thunderstorms. Front to stall out
across southern Missouri on Tuesday. Highs will be in the upper 70s
to low 80s on Monday, then dip down into the low 70s to low 80s
Tuesday and Wednesday.
Decent instability north of front Tuesday night, so could see
elevated activity develop and slide along boundary on nose of decent
low level jet. Large hail would be the main threat with this round
of storms.
Models are still indicating decent instability, CAPES in excess of
1500 J/kg and shear with system Wednesday afternoon, Wednesday night
as warm front lifts north through forecast area. All of this still
points to our first real potential severe weather day this spring,
but a lot can happen in 5 days. Stay tuned to further updates.
With everything a bit slower, main cold front to slide through early
on Thursday with precipitation tapering off to just slight chance
pops through Friday. Then extended models showing next system
lifting northeast towards forecast area Friday night and Saturday
with increasing chances of showers and thunderstorms once again.
Once system exits region on Thursday, will see precipitation taper
off. Even though it will be a bit cooler Thursday, highs will still
be a bit above normal in the mid 60s to upper 70s. Extended models
beginning to indicate another system approaching region on Friday,
but timing is hard to pin down. So for now kept slight chance pops.
Byrd
&&
.AVIATION... (For the 00z TAFs through 00z Sunday Evening)
Issued at 650 PM CDT Sat Apr 23 2016
Dry and VFR conditions are expected at the terminals. There may be
some patchy fog late tonight and early Sunday over southern
Illinois and southeast Missouri. Low level wind shear is still
possible at KUIN and KCOU between 09-15Z as a 35-40kt low level
jet sets up between 1000-2000 feet. This threat will end by mid
morning as mixing begins and the surface winds begin to pick up.
Do expect some gusts above 20kts during the late morning and
afternoon hours.
Specifics for KSTL: Dry and VFR conditions are expected the next
30 hours. Southerly winds will increase after 18Z on Sunday
afternoon with wind gusts over 20kts.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
705 PM CDT SAT APR 23 2016
.SHORT TERM... (Through Late Tonight)
Issued at 255 PM CDT Sat Apr 23 2016
Surface ridge extending from MI southwest into eastern MO will move
eastward. The stratus clouds across southeast IL should continue to
dissipate late this afternoon. Few-scattered diurnal cumulus
clouds, especially across parts of northeast and central MO will
dissipate early this evening with the loss of daytime heating.
Mainly just a little high level cloudiness tonight. Lows tonight
will be warmer than the previous night, mainly due to southeast
surface winds on the backside of the surface ridge. The warmest
temperatures will be across central MO with the coolest temperatures
in southwest IL. Lows tonight will be about 5 to 10 degrees above
normal for late April.
GKS
.LONG TERM... (Sunday through Next Saturday)
Issued at 255 PM CDT Sat Apr 23 2016
Dry and warmer weather to persist on Sunday, but will see an
increase in high clouds as next weather system approaches region.
With gusty south winds will see highs in the upper 70s to low 80s.
Sunday night rain chances to approach region, but models are a bit
slower with onset, so lowered pops just a bit. Then Monday through
Tuesday, frontal boundary to slowly slide south through area with
mainly scattered showers and thunderstorms. Front to stall out
across southern Missouri on Tuesday. Highs will be in the upper 70s
to low 80s on Monday, then dip down into the low 70s to low 80s
Tuesday and Wednesday.
Decent instability north of front Tuesday night, so could see
elevated activity develop and slide along boundary on nose of decent
low level jet. Large hail would be the main threat with this round
of storms.
Models are still indicating decent instability, CAPES in excess of
1500 J/kg and shear with system Wednesday afternoon, Wednesday night
as warm front lifts north through forecast area. All of this still
points to our first real potential severe weather day this spring,
but a lot can happen in 5 days. Stay tuned to further updates.
With everything a bit slower, main cold front to slide through early
on Thursday with precipitation tapering off to just slight chance
pops through Friday. Then extended models showing next system
lifting northeast towards forecast area Friday night and Saturday
with increasing chances of showers and thunderstorms once again.
Once system exits region on Thursday, will see precipitation taper
off. Even though it will be a bit cooler Thursday, highs will still
be a bit above normal in the mid 60s to upper 70s. Extended models
beginning to indicate another system approaching region on Friday,
but timing is hard to pin down. So for now kept slight chance pops.
Byrd
&&
.AVIATION... (For the 00z TAFs through 00z Sunday Evening)
Issued at 650 PM CDT Sat Apr 23 2016
Dry and VFR conditions are expected at the terminals. There may be
some patchy fog late tonight and early Sunday over southern
Illinois and southeast Missouri. Low level wind shear is still
possible at KUIN and KCOU between 09-15Z as a 35-40kt low level
jet sets up between 1000-2000 feet. This threat will end by mid
morning as mixing begins and the surface winds begin to pick up.
Do expect some gusts above 20kts during the late morning and
afternoon hours.
Specifics for KSTL: Dry and VFR conditions are expected the next
30 hours. Southerly winds will increase after 18Z on Sunday
afternoon with wind gusts over 20kts.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
629 PM CDT SAT APR 23 2016
.Short Term...(This Evening through Monday Night)
Issued at 309 PM CDT SAT APR 23 2016
Short Term (Tonight through Monday night):
The main concern in the short term will be the potential for a few
strong and isolated severe storms on Sunday evening into Sunday
night. Tonight, however will be much less interesting and quite
pleasant as modest southerly winds will hold temperatures in the mid
50s to lower 60s. The system, an upper level trough, that will bring
thunderstorms to the area Sunday will move from western Wyoming to
near the WY/SD/NE by Saturday night. This will force a cold front into
the western Plains. Thunderstorms will develop along this front
tonight across western Kansas. This storms will progress across
Kansas overnight enhanced by a 50-60kt SSWly nocturnal LLJ. By early
Sunday morning the LLJ will veer to the southwest and storms will
begin to approach northeastern KS and northwestern MO. However,
these storms will be weakening as they approach and there may just
be a few isolated storms or residual shower to make it into the
extreme NW CWA Sunday morning. However, by Sunday afternoon, a dry
line will exist across central Kansas with the attendant cold front
lagging to the west across the western High Plains. Thunderstorms
are expected to develop out ahead of the cold front across central
Kansas during the afternoon and move eastward. These storms will
have the potential to be strong with perhaps isolated severe storms
possible mainly across northwestern MO/northeastern KS where
dewpoints will be near 60 degrees, modest instability of 500-
800J/kg, and steep mid-level lapse rates will exist. However, shear
is not impressive and as previously mentioned instability is merely
modest. Consequently, strong storms will be possible and perhaps
even a marginally severe storm capable of producing large hail or
damaging winds. Storms will weaken Sunday night as storms move into
a more stable environment and the upper level trough continues to
weak as it moves into the Upper Midwest. On Monday, the cold front
associated with the upper level system will sag through the area.
However, will little forcing the front will sag through the area
with little activity expected. The best chance for storms would
occur head of the front where modest instability will reside. Monday
night the cold front will sink south of the area and become
stationary. A few thunderstorms may develop north of the stationary
boundary Monday as a SW 40kt LLJ overrides the boundary. These
thunderstorms may affect the southern CWA depending on the location
of the front.
.Long Term...(Tuesday through Saturday)
Issued at 309 PM CDT SAT APR 23 2016
Tuesday evening and Wednesday will bring another round of showers
and possibly severe thunderstorms to the CWA. The most recent NAM
and GFS runs show Tuesday morning and early afternoon warm and humid
with precipitation mainly staying just south of the WFO. A negatively
tilted low pressure trough stations itself over eastern CO/western KS
Tuesday afternoon. A cold front will move east through Kansas
Wednesday afternoon, and an associated warm front will be located E-W
through our forecast area late Tuesday bringing low- level moisture
with it. Dew point temperatures will range from low 50s north of the
front spreading south to the mid-60s. We will also have decent
instability and shear with CAPE values around 1000-2000 J/kg and
30-50 kt 0-6 km bulk shear. A combination of high CAPE and shear may
lead to potentially severe thunderstorms ahead of the cold front. The
development and location of severe weather will depend on the timing
of convection and the frontal passage, which will become more clear
as we get closer to the event. For now, the GFS and Euro models show
precipitation starting in eastern KS and moving east through the WFO
late Tuesday night through Wednesday morning. Convection could
continue throughout Wednesday as CAPE values are expected to stay
above 1000 J/kg throughout Wednesday afternoon.
High temperatures will continue to be in the mid 70s through
Wednesday, but will drop to the mid-high 60s for Thursday and Friday
after the cold front passes. Low temperatures will drop Thursday and
Friday mornings to the high 40s to low 50s. Thursday is expected to
be dry before another upper low system may cause more precipitation
late Friday into Saturday.
&&
.Aviation...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 629 PM CDT SAT APR 23 2016
VFR conditions anticipated through the fcst period with modest south
winds of 10-15 kts expected through the overnight before increasing
after 16z. Further aloft...a strong southwesterly low-level jet of
roughly 45 kts will lead to increasing LLWS concerns after 06z and a
mention has been added for all forecast locations. Precip chances in
the form of shwrs/storms look to increase after 21z...however the
mostly likely location right now appears to be STJ based on expected
dryline configuration. Will consider adding further south with the
next forecast issuance.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Short Term...73
Long Term...Chandler/CDB
Aviation...32
Area Forecast Discussion
National Weather Service Springfield MO
616 PM CDT SAT APR 23 2016
...00z Aviation Update...
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 616 PM CDT Sat Apr 23 2016
VFR conditions will again persist through this TAF cycle. Winds
have become southerly (as advertised) during the day today.
Surface winds will steadily increase through Sunday ahead of a
passing system over the plains. Gusty southerly winds can be
expected for SGF and JLN by Sunday afternoon and should continue
through the end of the period.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Frye
Area Forecast Discussion
National Weather Service Springfield MO
616 PM CDT SAT APR 23 2016
...00z Aviation Update...
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 616 PM CDT Sat Apr 23 2016
VFR conditions will again persist through this TAF cycle. Winds
have become southerly (as advertised) during the day today.
Surface winds will steadily increase through Sunday ahead of a
passing system over the plains. Gusty southerly winds can be
expected for SGF and JLN by Sunday afternoon and should continue
through the end of the period.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Frye
Area Forecast Discussion
National Weather Service Springfield MO
328 PM CDT SAT APR 23 2016
...Beautiful Weather This Weekend...Increasing Confidence for
Strong to Severe Storms Next Week...
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1159 AM CDT Sat Apr 23 2016
VFR conditions are expected through the period as surface high
pressure continues to drift eastward and an upper level ridge
moves across the area. Main forecast concern is gusty winds
beginning after sunrise on Sunday as the next approaching system
begins to tighten up the surface pressure gradient. Winds should
develop gusts after 13z at KSGF/KJLN but believe that it will be
later in the afternoon...after the end of the forecast
period...for KBBG.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Gaede
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
310 PM CDT SAT APR 23 2016
.Short Term...(This Evening through Monday Night)
Issued at 309 PM CDT SAT APR 23 2016
Short Term (Tonight through Monday night):
The main concern in the short term will be the potential for a few
strong and isolated severe storms on Sunday evening into Sunday
night. Tonight, however will be much less interesting and quite
pleasant as modest southerly winds will hold temperatures in the mid
50s to lower 60s. The system, an upper level trough, that will bring
thunderstorms to the area Sunday will move from western Wyoming to
near the WY/SD/NE by Saturday night. This will force a cold front into
the western Plains. Thunderstorms will develop along this front
tonight across western Kansas. This storms will progress across
Kansas overnight enhanced by a 50-60kt SSWly nocturnal LLJ. By early
Sunday morning the LLJ will veer to the southwest and storms will
begin to approach northeastern KS and northwestern MO. However,
these storms will be weakening as they approach and there may just
be a few isolated storms or residual shower to make it into the
extreme NW CWA Sunday morning. However, by Sunday afternoon, a dry
line will exist across central Kansas with the attendant cold front
lagging to the west across the western High Plains. Thunderstorms
are expected to develop out ahead of the cold front across central
Kansas during the afternoon and move eastward. These storms will
have the potential to be strong with perhaps isolated severe storms
possible mainly across northwestern MO/northeastern KS where
dewpoints will be near 60 degrees, modest instability of 500-
800J/kg, and steep mid-level lapse rates will exist. However, shear
is not impressive and as previously mentioned instability is merely
modest. Consequently, strong storms will be possible and perhaps
even a marginally severe storm capable of producing large hail or
damaging winds. Storms will weaken Sunday night as storms move into
a more stable environment and the upper level trough continues to
weak as it moves into the Upper Midwest. On Monday, the cold front
associated with the upper level system will sag through the area.
However, will little forcing the front will sag through the area
with little activity expected. The best chance for storms would
occur head of the front where modest instability will reside. Monday
night the cold front will sink south of the area and become
stationary. A few thunderstorms may develop north of the stationary
boundary Monday as a SW 40kt LLJ overrides the boundary. These
thunderstorms may affect the southern CWA depending on the location
of the front.
.Long Term...(Tuesday through Saturday)
Issued at 309 PM CDT SAT APR 23 2016
Tuesday evening and Wednesday will bring another round of showers
and possibly severe thunderstorms to the CWA. The most recent NAM
and GFS runs show Tuesday morning and early afternoon warm and humid
with precipitation mainly staying just south of the WFO. A negatively
tilted low pressure trough stations itself over eastern CO/western KS
Tuesday afternoon. A cold front will move east through Kansas
Wednesday afternoon, and an associated warm front will be located E-W
through our forecast area late Tuesday bringing low- level moisture
with it. Dew point temperatures will range from low 50s north of the
front spreading south to the mid-60s. We will also have decent
instability and shear with CAPE values around 1000-2000 J/kg and
30-50 kt 0-6 km bulk shear. A combination of high CAPE and shear may
lead to potentially severe thunderstorms ahead of the cold front. The
development and location of severe weather will depend on the timing
of convection and the frontal passage, which will become more clear
as we get closer to the event. For now, the GFS and Euro models show
precipitation starting in eastern KS and moving east through the WFO
late Tuesday night through Wednesday morning. Convection could
continue throughout Wednesday as CAPE values are expected to stay
above 1000 J/kg throughout Wednesday afternoon.
High temperatures will continue to be in the mid 70s through
Wednesday, but will drop to the mid-high 60s for Thursday and Friday
after the cold front passes. Low temperatures will drop Thursday and
Friday mornings to the high 40s to low 50s. Thursday is expected to
be dry before another upper low system may cause more precipitation
late Friday into Saturday.
&&
.Aviation...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1230 PM CDT SAT APR 23 2016
VFR conds will prevail through the pd with mainly just sct high
clouds expected. Winds will pick up out of the south this afternoon
to 10-15kts with gusts to around 20kts. Winds will lose their gusts
this evening but still remain around 10-15kts. However, tomorrow
morning winds will again increase to 15-20kts with gusts to 25-30kts.
LLWS may be a marginal concern tonight as winds at 2kft will be out
of the SSW at 35-40kts btn 06Z-14Z and, may need to be added to the
TAF at the 00Z issuance.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Short Term...73
Long Term...Chandler/CDB
Aviation...73
Area Forecast Discussion
National Weather Service Saint Louis MO
257 PM CDT SAT APR 23 2016
.SHORT TERM... (Through Late Tonight)
Issued at 255 PM CDT Sat Apr 23 2016
Surface ridge extending from MI southwest into eastern MO will move
eastward. The stratus clouds across southeast IL should continue to
dissipate late this afternoon. Few-scattered diurnal cumulus
clouds, especially across parts of northeast and central MO will
dissipate early this evening with the loss of daytime heating.
Mainly just a little high level cloudiness tonight. Lows tonight
will be warmer than the previous night, mainly due to southeast
surface winds on the backside of the surface ridge. The warmest
temperatures will be across central MO with the coolest temperatures
in southwest IL. Lows tonight will be about 5 to 10 degrees above
normal for late April.
GKS
.LONG TERM... (Sunday through Next Saturday)
Issued at 255 PM CDT Sat Apr 23 2016
Dry and warmer weather to persist on Sunday, but will see an
increase in high clouds as next weather system approaches region.
With gusty south winds will see highs in the upper 70s to low 80s.
Sunday night rain chances to approach region, but models are a bit
slower with onset, so lowered pops just a bit. Then Monday through
Tuesday, frontal boundary to slowly slide south through area with
mainly scattered showers and thunderstorms. Front to stall out
across southern Missouri on Tuesday. Highs will be in the upper 70s
to low 80s on Monday, then dip down into the low 70s to low 80s
Tuesday and Wednesday.
Decent instability north of front Tuesday night, so could see
elevated activity develop and slide along boundary on nose of decent
low level jet. Large hail would be the main threat with this round
of storms.
Models are still indicating decent instability, CAPES in excess of
1500 J/kg and shear with system Wednesday afternoon, Wednesday night
as warm front lifts north through forecast area. All of this still
points to our first real potential severe weather day this spring,
but a lot can happen in 5 days. Stay tuned to further updates.
With everything a bit slower, main cold front to slide through early
on Thursday with precipitation tapering off to just slight chance
pops through Friday. Then extended models showing next system
lifting northeast towards forecast area Friday night and Saturday
with increasing chances of showers and thunderstorms once again.
Once system exits region on Thursday, will see precipitation taper
off. Even though it will be a bit cooler Thursday, highs will still
be a bit above normal in the mid 60s to upper 70s. Extended models
beginning to indicate another system approaching region on Friday,
but timing is hard to pin down. So for now kept slight chance pops.
Byrd
&&
.AVIATION... (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1104 AM CDT Sat Apr 23 2016
Surface ridge extending from the Great Lakes region southwest
into eastern MO will shift eastward this period. The low level
cloudiness over eastern IA into northeast MO should remain north
of UIN this afternoon. The stratus cloudiness across southeast IL
should gradually dissipate this afternoon with daytime heating,
mixing and drying and remain east of the St Louis metro area.
There may be a few diurnal cumulus clouds at the taf sites this
afternoon. There will be a little high level cloudiness late
tonight and Sunday morning. Southeasterly surface winds should
strengthen at UIN and COU through the forecast period as the
surface pressure gradient gradually tightens, becoming more
southerly on Sunday. Light northeast wind in the St Louis metro
area will also strengthen as well through the period, veering
around to a southeast direction by early this evening, then
southerly Sunday morning. There will be some LLWS conditions in
UIN and COU very late tonight and early Sunday morning as a
southwesterly low level jet translates eastward into northwest MO
with both speed and directional shear in the lowest 1000 feet.
Specifics for KSTL: Stratus clouds across southeast IL should
gradually dissipate this afternoon and remain east-southeast of
STL. Few diurnal cumulus clouds may develop this afternoon due to
daytime heating, then dissipate early this evening. There will be
some high level cloudiness late tonight and Sunday. Light
northeast wind will increase in speed to 8-10 kts by late this
afternoon or early this evening as it veers around to a southeast
direction. The surface wind will become southerly Sunday morning
and possibly gusty Sunday afternoon.
GKS
&&
.PRELIMINARY POINT TEMPS/POPS...
Saint Louis 55 82 63 81 / 0 0 20 30
Quincy 56 81 61 79 / 5 5 30 30
Columbia 57 81 60 78 / 5 5 20 30
Jefferson City 58 82 61 80 / 5 5 20 30
Salem 51 79 60 80 / 0 0 10 20
Farmington 52 79 60 79 / 0 0 10 20
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1230 PM CDT SAT APR 23 2016
.Discussion...
Issued at 412 AM CDT SAT APR 23 2016
Today - Tonight:
In the very near term will be dealing with patchy dense fog over the
northeast 1/2 of the CWA. The fog and stratus is forming under a
surface ridge with river valleys and low lying areas the most
susceptible. The latest NAM/RAP 925mb condensation pressure deficit
prog best depict the low clouds with the SREF favoring more
widespread dense fog further north in IA.
Otherwise, for today expect a nice warm up as pressure falls over
the Central Plains induce increasing southerly winds. Should see
decent mixing with a dry adiabatic lapse rate yielding highs around
10 degrees above average. Upper level ridging spreading east into
the CWA will provide for continued dry conditions.
Increasing warm air advection aloft will ensue across KS and NE this
evening with scattered elevated convection possibly grazing far
northwest MO towards sunrise Sunday morning. Any convection which
reaches this region should fall apart Sunday morning with convective
debris and mid level accas likely lingering over the western CWA
into the afternoon.
Sunday - Sunday night:
The weather will become more interesting late Sunday afternoon into
the evening as an upper level closed low migrates into SD/NE. A
negatively tilted shortwave trough is progged to rotate from under
the upper low and lift northeast across KS and NE during the
afternoon. A moderately strong low level jet around 45kts will pull
deeper low level moisture ahead of a north-south dryline which will
anchor over central KS and far western OK. Expect to see scattered
strong/severe convection form along the dryline by mid/late
afternoon and track quickly northeast. Far northwest MO stands the
best chance of seeing active convection. Surface based CAPEs around
1500 J/kg and 0-6km shear around 40kts will support
strong/marginally severe storms over this area. All models strongly
suggest the dryline will move little to the east so the severe
threat in the CWA will likely be limited to far northwest MO.
Convection will weaken and decrease in coverage as it moves east
through the CWA with the far southeastern counties receiving the
least QPF.
Monday - Friday:
A fairly active period with two more closed upper lows likely
affecting the region. While Monday initially looked relatively quiet
as the Upper MS Valley system pulls away there is some concern that
some afternoon convection could form along the remnants of a stalled
surface boundary. The limiting factor will be increasing mid level
heights and a lack of upper support. Nonetheless with a front in the
CWA will need to be vigilant.
As we`ve been discussing over the past few days a second and
stronger upper system will become a factor and play a significant
role in our weather by Tuesday night and continuing into Wednesday.
Medium range operational models continue to eject a negatively
tilted shortwave through KS and MO. There is every reason to believe
a west-east frontal boundary will be in the vicinity with this
feature lifting north and through the CWA. Low-level moisture will
not be a problem with low/mid 60 dewpoints likely south of the front
and spreading northward. The GFS indicates 2000-3000 J/kg of CAPE
could be available with 30-40kt 0-6km shear so severe storms are a
growing concern. As always timing of the front and convective
development will determine where severe will occur but our CWA is
currently within the window of opportunity.
Convection could linger well into Wednesday as the upper low opens
up and lifts through NE/KS/IA/MO.
Thursday looks quiet as we`ll be between systems. The third system
we`ll be keeping an eye on will be yet another closed upper low.
This feature may not be a factor until late Friday.
Through out this period expect to see above average temperatures with
an overall increase in humidity.
&&
.Aviation...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1230 PM CDT SAT APR 23 2016
VFR conds will prevail through the pd with mainly just sct high
clouds expected. Winds will pick up out of the south this afternoon
to 10-15kts with gusts to around 20kts. Winds will lose their gusts
this evening but still remain around 10-15kts. However, tomorrow
morning winds will again increase to 15-20kts with gusts to 25-30kts.
LLWS may be a marginal concern tonight as winds at 2kft will be out
of the SSW at 35-40kts btn 06Z-14Z and, may need to be added to the
TAF at the 00Z issuance.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...MJ
Aviation...73
Area Forecast Discussion
National Weather Service Springfield MO
1206 PM CDT SAT APR 23 2016
.SHORT TERM...(Today through Sunday)
Issued at 330 AM CDT Sat Apr 23 2016
An upper level ridge is currently building over the region early
this morning and will be centered over the area by tonight. As an
upper level trough tracks east into the northern Plains on Sunday
the ridge will start to spread off Sunday night.
Warm and dry conditions will occur through much of this weekend
as highs warm into the upper 70s to the lower 80s both afternoons.
Sunny skies will occur today with partly cloudy skies occurring on
Sunday. Gusty southerly winds will develop Sunday afternoon as
surface low pressure develops across the central Plains ahead of
the upper level low. Wind gusts over 30 mph can be expected for
locations generally along and west of Hwy 65 Sunday afternoon.
.LONG TERM...(Sunday night through Friday)
Issued at 330 AM CDT Sat Apr 23 2016
As the upper level low tracks east storms are expected to develop
to the west and northwest of the area along a cold front Sunday
evening. The front will then drop to the southeast into the area
Sunday night into Monday. The better lift and instability will
remain to the northwest and north of the area as the upper level
trough remains well north of the area. There will be an
instability gradient that sets up close to the far northwestern
portions of the area, so storms will be weakening as they move
southeast into the area, but a few strong storms may still be
possible generally northwest of a Pittsburg KS to Nevada MO line
Sunday night into early Monday morning. Coverage in storms will be
decreasing as the storms move into the area and will be isolated
to scattered in nature and many locations will remain dry. It is
also possible the storms dissipate just to the northwest of the
area.
As the front moves south through the area on Monday a few
thunderstorms will be possible, but overall most locations will
remain dry as coverage will be very limited with this activity.
Instability is expected to remain on the weak side, therefore,
not expecting a severe risk Monday.
Another upper level low will push into the northwestern U.S.
Sunday then dig to the south into the southwestern U.S. Monday
then lift to the northeast across the plains by Wednesday. As the
upper level low lifts to the northeast, the front that moves
south through the region Sunday night into Monday will lift back
to the north as a warm front Monday night into Tuesday morning.
Scattered storm chances will occur again along the front as it
lifts north.
Instability will then increase across the region on Tuesday ahead
of the approaching storm system, but a strong cap will also
develop across the area. The strong lift with this system will
remain well west of the area through the day on Tuesday, Therefore
most of the day should be dry after the warm front lifts north of
the area.
Storms are expected to develop across central Kansas
to the south into central Texas Tuesday evening along a cold
front. The front will then track east Tuesday night into Wednesday
Wednesday across the area. There is still some question on the
exact timing of the front but it will be at some point during the
day on Wednesday. There will be a severe risk with the storms
overnight Tuesday into Wednesday as the gulf moisture and an
unstable air mass will be in place across the area, large hail and
strong winds will be the main risk.
As the system moves off to the east mostly dry weather will occur
on Thursday. Then another system will begin to track into the
region Friday into the start of the weekend brining additional
chances for thunderstorms to the area.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1159 AM CDT Sat Apr 23 2016
VFR conditions are expected through the period as surface high
pressure continues to drift eastward and an upper level ridge
moves across the area. Main forecast concern is gusty winds
beginning after sunrise on Sunday as the next approaching system
begins to tighten up the surface pressure gradient. Winds should
develop gusts after 13z at KSGF/KJLN but believe that it will be
later in the afternoon...after the end of the forecast
period...for KBBG.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...Gaede
Area Forecast Discussion
National Weather Service Springfield MO
1206 PM CDT SAT APR 23 2016
.SHORT TERM...(Today through Sunday)
Issued at 330 AM CDT Sat Apr 23 2016
An upper level ridge is currently building over the region early
this morning and will be centered over the area by tonight. As an
upper level trough tracks east into the northern Plains on Sunday
the ridge will start to spread off Sunday night.
Warm and dry conditions will occur through much of this weekend
as highs warm into the upper 70s to the lower 80s both afternoons.
Sunny skies will occur today with partly cloudy skies occurring on
Sunday. Gusty southerly winds will develop Sunday afternoon as
surface low pressure develops across the central Plains ahead of
the upper level low. Wind gusts over 30 mph can be expected for
locations generally along and west of Hwy 65 Sunday afternoon.
.LONG TERM...(Sunday night through Friday)
Issued at 330 AM CDT Sat Apr 23 2016
As the upper level low tracks east storms are expected to develop
to the west and northwest of the area along a cold front Sunday
evening. The front will then drop to the southeast into the area
Sunday night into Monday. The better lift and instability will
remain to the northwest and north of the area as the upper level
trough remains well north of the area. There will be an
instability gradient that sets up close to the far northwestern
portions of the area, so storms will be weakening as they move
southeast into the area, but a few strong storms may still be
possible generally northwest of a Pittsburg KS to Nevada MO line
Sunday night into early Monday morning. Coverage in storms will be
decreasing as the storms move into the area and will be isolated
to scattered in nature and many locations will remain dry. It is
also possible the storms dissipate just to the northwest of the
area.
As the front moves south through the area on Monday a few
thunderstorms will be possible, but overall most locations will
remain dry as coverage will be very limited with this activity.
Instability is expected to remain on the weak side, therefore,
not expecting a severe risk Monday.
Another upper level low will push into the northwestern U.S.
Sunday then dig to the south into the southwestern U.S. Monday
then lift to the northeast across the plains by Wednesday. As the
upper level low lifts to the northeast, the front that moves
south through the region Sunday night into Monday will lift back
to the north as a warm front Monday night into Tuesday morning.
Scattered storm chances will occur again along the front as it
lifts north.
Instability will then increase across the region on Tuesday ahead
of the approaching storm system, but a strong cap will also
develop across the area. The strong lift with this system will
remain well west of the area through the day on Tuesday, Therefore
most of the day should be dry after the warm front lifts north of
the area.
Storms are expected to develop across central Kansas
to the south into central Texas Tuesday evening along a cold
front. The front will then track east Tuesday night into Wednesday
Wednesday across the area. There is still some question on the
exact timing of the front but it will be at some point during the
day on Wednesday. There will be a severe risk with the storms
overnight Tuesday into Wednesday as the gulf moisture and an
unstable air mass will be in place across the area, large hail and
strong winds will be the main risk.
As the system moves off to the east mostly dry weather will occur
on Thursday. Then another system will begin to track into the
region Friday into the start of the weekend brining additional
chances for thunderstorms to the area.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1159 AM CDT Sat Apr 23 2016
VFR conditions are expected through the period as surface high
pressure continues to drift eastward and an upper level ridge
moves across the area. Main forecast concern is gusty winds
beginning after sunrise on Sunday as the next approaching system
begins to tighten up the surface pressure gradient. Winds should
develop gusts after 13z at KSGF/KJLN but believe that it will be
later in the afternoon...after the end of the forecast
period...for KBBG.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...Gaede
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1140 AM CDT SAT APR 23 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 350 AM CDT Sat Apr 23 2016
Focus today will be clouds and temps.
Sfc ridge will continue to drift ewd today, allowing sly winds to
return to wrn portions of the CWA. Winds elsewhere are expected to
remain sely to ely.
The area of clouds currently just E of the CWA shud remain E.
However, some clouds may drift into ern portions of the CWA mainly
this morning until the ridge pushes them out of the area.
A secondary ridge axis over nrn portions of the CWA is expected to
be the focus for FG/stratus this morning. There is still uncertainty
regarding how widespread any FG will be, as well as any stratus. The
additional moisture within the bndy layer across this region shud
allow for at least sct clouds this morning, dissipating thru the
afternoon.
All of this leads to a rather complex temp forecast for today. For
ern portions of the CWA, have kept temps cooler where the ridge axis
will remain in place longer. Areas under this ridge yesterday saw
temps in the upper 60s, however, believe there will be less cloud
cover today. Believe the warmer temps will build into wrn portions
of the CWA where winds will become sly as well as the thermal ridge
building into this area. Have gone with trends close to a blend of
the RAP and local 4km WRF, which has been a good mix in these
setups. Did trend slightly cooler than this blend across nrn
portions of the CWA where more questions exist regarding cloud cover
today.
Tilly
.LONG TERM... (Tonight through Friday)
Issued at 350 AM CDT Sat Apr 23 2016
An upper level longwave RIDGE axis will persist over the Plains
thru much of next week, with upper longwave TROFs on the west and
east coasts. A series of strong Pacific storms will run thru this
RIDGE, being dropped off from the west coast TROF and being picked
up by the east coast TROF a few days later, with an overall track to
the E-NE thru our region. It would seem that each successive storm
system will track a bit further south than its predecessor.
The first storm system is slated to track to our north late Sunday
and into Monday, and will be mostly a glancing blow to our region as
a result, with what forms mostly upstream initially to our northwest
as it is thrown in our direction and largely weakens as it moves in.
This convection may also create additional boundaries during Monday
afternoon and early evening to maintain the threat for showers and
thunderstorms.
In the wake of this first storm system, a cold front will drop down
late Monday night into Tuesday and will maintain a low chance for
rain.
The second Pacific storm system will be more of a direct hit as it
will initially correspond well with the surface frontal boundary
buckling north as a warm front Wednesday morning. This should
result in elevated storms with hail as their primary threat during
that time.
Heading into Wednesday afternoon and evening, it will depend heavily
on how far north the front gets. Models have been trending with
less northward progress from 24hrs ago, but anywhere to the south of
it will have plenty of instability and moisture as well as strong
shear for more surface-based storms which will have a good potential
for some severe.
The rain potential lingers into Thursday if the cold front slows
enough to not make it thru until this day.
Friday should be a dry day, finally, but it appears only briefly
until yet another storm system approaches from the west in time for
the following weekend.
Otherwise, the longwave RIDGE setup will ensure that temps remain at
or above average throughout the period.
TES
&&
.AVIATION... (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1104 AM CDT Sat Apr 23 2016
Surface ridge extending from the Great Lakes region southwest
into eastern MO will shift eastward this period. The low level
cloudiness over eastern IA into northeast MO should remain north
of UIN this afternoon. The stratus cloudiness across southeast IL
should gradually dissipate this afternoon with daytime heating,
mixing and drying and remain east of the St Louis metro area.
There may be a few diurnal cumulus clouds at the taf sites this
afternoon. There will be a little high level cloudiness late
tonight and Sunday morning. Southeasterly surface winds should
strengthen at UIN and COU through the forecast period as the
surface pressure gradient gradually tightens, becoming more
southerly on Sunday. Light northeast wind in the St Louis metro
area will also strengthen as well through the period, veering
around to a southeast direction by early this evening, then
southerly Sunday morning. There will be some LLWS conditions in
UIN and COU very late tonight and early Sunday morning as a
southwesterly low level jet translates eastward into northwest MO
with both speed and directional shear in the lowest 1000 feet.
Specifics for KSTL: Stratus clouds across southeast IL should
gradually dissipate this afternoon and remain east-southeast of
STL. Few diurnal cumulus clouds may develop this afternoon due to
daytime heating, then dissipate early this evening. There will be
some high level cloudiness late tonight and Sunday. Light
northeast wind will increase in speed to 8-10 kts by late this
afternoon or early this evening as it veers around to a southeast
direction. The surface wind will become southerly Sunday morning
and possibly gusty Sunday afternoon.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1051 AM CDT SUN APR 24 2016
.UPDATE...
ISSUED AT 1051 AM CDT SUN APR 24 2016
995 MB LOW PRES WAS OVER CNTRL SD. THE COLD FRONT ALOFT IS
CURRENTLY OVER CNTRL NEB/KS...SLIGHTLY AHEAD OF THE DRY TROF WHICH
EXTENDS FROM ODX-HDE-NRN. SCT SHWRS HAVE STARTED DEVELOPING IN THE
LAST HR.
DWPTS ARE IN THE MID-UPR 50S AHEAD OF THE SFC TROF. UPDATED THE
FCST USING THE 13 KM RAP WHICH BRINGS VERY DRY DWPTS IN FROM THE W
THIS AFTN. DWPTS ARE IN THE 30S JUST W OF THE FCST AREA AT
IML/OGA/LBF/TIF/BBW.
EXPECT SCT SHWRS TO BECOME TSTMS ESPECIALLY BY 3 PM E OF HWY 281.
SHOULD BE DRY TO THE W OF 281 BY THAT TIME. THE TSTMS SHOULD EXIT
THE FCST AREA AND BE INTO ERN NEB/KS BY 6 PM.
CLOUDS WILL INHIBIT HEATING SOME...BUT STILL EXPECT MLCAPE UP TO
1500 J/KG. DEEP LAYER SHEAR WILL BE ABOUT 40 KTS WITH A FAIRLY
UNIDIRECTIONAL PROFILE. INITIAL STORMS COULD BE SUPERCELLULAR.
MEAN CELL MVMT WILL BE TO THE NE AT 40-45 KTS.
GOES E GOES INTO RAPID SCAN MODE AT 1814Z.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 336 AM CDT SUN APR 24 2016
THE MAIN CONCERN TODAY AND TONIGHT IS HOW WIDESPREAD SHOWERS AND
THUNDERSTORMS WILL BE. LIGHT SCATTERED ACTIVITY IS ONGOING THIS
MORNING AND IS EXPECTED TO BECOME MORE WIDESPREAD AS IT MOVES
EASTWARD. THE MAJORITY ACTIVITY IS EXPECTED TO MOVE EAST OF
HIGHWAY 81 BY SUNRISE. ACTIVITY IS EXPECTED TO DIMINISH BY MID-
MORNING...BUT INCREASE AGAIN DURING THE AFTERNOON. THE HIGH-RES
GUIDANCE INDICATES THE CHANCE FOR SHOWERS AND THUNDERSTORMS TO
DEVELOP AROUND THE TRI-CITIES AND MOVE EASTWARD DURING THE MID
AFTERNOON HOWEVER...HAVE KEPT THE FORECAST IN THIS AREA MAINLY DRY
DUE TO LOW CONFIDENCE ON THIS OCCURRING...SO WILL NEED TO WATCH IF
THIS OCCURS. MAINLY EXPECTING SKIES TO SCATTER ACROSS WESTERN
SECTIONS AND HIGHS TO BE IN THE UPPER 70S AND LOW 80S. COOLER IN
THE EAST WHERE CLOUDS ARE EXPECTED TO PERSIST MUCH OF THE DAY.
THE UPPER LOW WILL MOVE ACROSS THE NE/SD BORDER. THE FRONT/TROUGH
WILL BE SLOW TO MAKE MUCH EASTWARD MOVEMENT UNTIL THE UPPER LOW
BEGINS TO MOVE NORTHEAST. A BIG QUESTION IS HOW QUICKLY WILL THE
UPPER LOW MOVE...WHICH WILL BE IMPORTANT FOR HOW FAR EAST THE
FRONT WILL MOVE. IF IT SLOWS DOWN...AS HIGH-RES GUIDANCE IS
INDICATING...SOME STRONG TO SEVERE STORMS MAY DEVELOP ALONG AND
EAST OF HIGHWAY 281. INSTABILITY OF 1500-2000J/KG MUCAPE AND
45-50KTS SHEAR IS AMPLE FOR ANY STORM TO BE SEVERE. LARGE HAIL AND
DAMAGING WIND ARE THE MAIN THREATS. THESE STORMS WILL QUICKLY MOVE
EAST/NORTHEAST AND SHOULD MOVE INTO EASTERN NEBRASKA AROUND OR
JUST AFTER SUNSET.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 336 AM CDT SUN APR 24 2016
MONDAY THERE IS A WEAK UPPER LEVEL RIDGE AND SURFACE HIGH ACROSS
THE AREA. TEMPERATURES WILL REMAIN ON THE WARM SIDE...BUT A LITTLE
COOLER THAN TODAY. BY MONDAY NIGHT THERE IS A SURFACE LOW
DEVELOPING ON THE HIGH PLAINS AND AN UPPER LEVEL LOW IN THE FOUR
CORNERS REGION. WITH THE SURFACE LOW IN WESTERN KANSAS THE WINDS
ACROSS THE AREA WILL TURN TO THE EAST/SOUTHEAST AND BRING IN
MOISTURE TO THE AREA. THERE COULD BE A LITTLE PRECIPITATION MAINLY
IN THE SOUTHWEST PART OF THE FORECAST AREA LATE MONDAY NIGHT.
ON TUESDAY THE UPPER LEVEL LOW MOVES INTO THE HIGH PLAINS AND
THUNDERSTORMS SPREAD ACROSS THE FORECAST AREA. THE UPPER LEVEL LOW
CONTINUES TO MOVE TO THE NORTHEAST AND ACROSS THE FORECAST AREA
TUESDAY NIGHT. THE SURFACE LOW ALSO MOVES THROUGH THE AREA WITH A
WARM FRONT TO THE EAST OF THE LOW. MUCAPE OF UP TO 5000 J/KG ARE
FORECAST...MAINLY ACROSS NORTH CENTRAL KANSAS. THE WARM FRONT
MOVES TO THE NORTH DURING THE AFTERNOON AND EVENING EVEN WHEN THE
MUCAPE DECREASES SOME. EXPECT THERE TO BE THUNDERSTORMS AND SOME
OF THEM COULD BE STRONG TO SEVERE.
MODELS HAVE A FEW DIFFERENCES FOR WEDNESDAY AND BEYOND. THE TRACK
AND SPEED OF THE UPPER LEVEL LOW ARE A LITTLE DIFFERENT. THE GFS
TAKES THE LOW A LITTLE FURTHER NORTH AND IS A LITTLE FASTER THAN
THE ECMWF. WITH THE FURTHER NORTH TRACK THE PRECIPITATION COMES TO
AN END IN THE SOUTHERN PART OF THE FORECAST AREA A LITTLE EARLIER.
THE THUNDERSTORMS ARE EXPECTED TO CONTINUE ACROSS THE AREA ON
WEDNESDAY. WEDNESDAY NIGHT EVEN THE ECMWF STARTS TO PULL FAR
ENOUGH TO THE NORTH THAT THE PRECIPITATION SHOULD COME TO AN END
FROM SOUTH TO NORTH. THERE IS LITTLE CAPE LEFT WEDNESDAY NIGHT SO
HAVE JUST SHOWERS. ON THURSDAY THERE STILL COULD BE A FEW SHOWERS
IN THE FAR NORTHERN PART OF THE REGION.
THE PERIOD THURSDAY NIGHT THROUGH SATURDAY THERE IS ANOTHER UPPER
LEVEL SYSTEM SET TO AFFECT THE AREA. THE MODELS CONTINUE TO HAVE A
FEW DIFFERENCES IN TRACK AND STRENGTH OF THE LOW. EVEN WITH THE
DIFFERENCES BOTH THE GFS AND ECMWF HAVE SOME PRECIPITATION ACROSS
THE AREA AND THIS WILL BE ANOTHER CHANCE FOR THUNDERSTORMS AGAIN.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z MON MORNING)
ISSUED AT 550 AM CDT SUN APR 24 2016
THE MAIN AVIATION FORECAST CONCERN IS THE CHANCE FOR SCATTERED
SHOWERS/THUNDERSTORMS TO IMPACT THE TERMINALS THIS AFTERNOON IN
ADDITION TO A WIND SHIFT.
A WIND SHIFT ALONG A SURFACE FRONT/TROUGH WILL MOVE THROUGH THE
AREA CAUSING WINDS TO BECOME MORE SOUTHWESTERLY. BRIEF SHOWERS AND
ISOLATED THUNDERSTORMS MAY IMPACT THE TERMINALS THIS AFTERNOON
AROUND 18Z. DUE TO THE ISOLATED NATURE HAVE LEFT THIS OUT...BUT IT
COULD IMPACT BOTH KEAR/KGRI. THEN AROUND 20Z HIGH-RES GUIDANCE
SHOWS THE CHANCE FOR THUNDERSTORMS TO DEVELOP ALONG THE FRONT.
THIS ACTIVITY COULD ORIGINATE AROUND THE KGRI TERMINAL. IT WILL
QUICKLY MOVE EASTWARD AND SKIES WILL CLEAR. AT THIS TIME DUE TO
THE UNCERTAINTY THAT STORMS MAY ACTUALLY DEVELOP AS FAR WEST AS
KGRI...HAVE LEFT ANY THUNDERSTORM MENTION OUT OF THE FORECAST.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...BILLINGS WRIGHT
LONG TERM...JCB
AVIATION...BILLINGS WRIGHT
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
624 AM CDT SUN APR 24 2016
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 315 AM CDT SUN APR 24 2016
THE POTENTIAL FOR SEVERE STORMS TODAY IS THE MAIN FCST CONCERN.
CLOSED LOW AT 500 MB WAS NEAR THE UT/WY/CO BORDER AREA AT 00Z WITH
12 HOUR HEIGHT FALLS OF UP TO AROUND 80 METERS JUST AHEAD OF THE
CIRCULATION CENTER. THERE WAS A JET SEGMENT OF AROUND 70 KTS AT
300 MB NEAR THE UT/CO BORDER. AT 700 MB...THERMAL RIDGE AXIS
STRETCHED FROM SWRN NM UP INTO SERN MT. MOIST AXIS AT 850 MB
EXTENDED FROM TX INTO THE DKTS. WATER VAPOR STLT IMAGERY EARLY
THIS MORNING SHOWED THE MID TROPOSPHERIC LOW HAD PROGRESSED INTO
CENTRAL WY. SFC ANLYS AT 08Z HAD A LOW PRES CENTER OVER WRN SD.
A WMFNT EXTENDED E/NE FROM THE LOW INTO MN AND A CDFNT EXTENDED
S/SW INTO NERN NM. DEWPOINTS AHEAD OF THE CDFNT WERE IN THE UPPER
40S AND LOWER 50S.
TODAY...CURRENT SHOWERS AND TSTMS TO OUR WEST SHOULD MOVE INTO
THE AREA THIS MORNING BUT IT APPEARS THESE WILL STAY BELOW SVR
LIMITS. RECENT RUNS OF THE RAP AND HRRR MODELS DEPICT VIGOROUS
STORM DEVELOPMENT IN OUR AREA THIS AFTN. SFC-500 METER MIXED
LAYER CAPE VALUES COULD REACH AROUND 2000 J/KG BY MID AFTN IN OUR
WRN ZONES...BASED ON DEWPOINTS RISING TO THE MID/UPPER 50S. THE
STRONGEST STORMS SHOULD FORM THERE AND THEN DVLP EWD. ZERO TO 6 KM
SHEAR VALUES OF 35-45 KTS SHOULD BE ENOUGH FOR SOME SUPERCELLS...
WITH HAIL THE MOST LIKELY HAZARD. EXPERIMENTAL HRRR AND MANY OTHER
CONVECTION ALLOWING MODELS SHOW SIMILAR RESULTS. LOOK FOR HIGHS 75
TO 80.
STORMS SHOULD CONTINUE TO DVLP EWD AND MAINLY BE OUT OF THE AREA
BY 06Z TNGT. SOME SMALL CHANCE OF SHOWERS MAY LINGER INTO THE
EARLY MORNING HOURS...MAINLY NEAR THE SD BORDER. SFC LOW SHOULD BE
JUST NW OF KSUX BY 12Z MON...THEN THAT WILL MOVE TO NEAR THE
WI/IA/MN BORDER AREA BY 00Z TUE. NW SFC WINDS SHOULD PULL COOLER
AIR INTO NERN NE FOR MON...BUT COOLING WILL BE LESS FOR SERN NE
AND SWRN IA. THERE COULD BE SOME LGT PCPN IN OUR NRN COUNTIES MON
BUT FOR NOW KEPT MON INTO MON NGT DRY. OUR NEXT CHANCE OF SHOWERS
AND TSTMS WILL BE ON TUE...AS LOW PRES INTENSIFIES OVER ERN CO AND
WRN KS. LOCATION OF A NWD LIFTING WMFNT WILL BE CRITICAL...BUT IT
DOES APPEAR THERE WILL BE ENOUGH INSTABILITY IN SERN NE FOR SOME
STG TO SVR STORMS TUE AFTN AND EVENING.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 315 AM CDT SUN APR 24 2016
OVERALL THIS PERIOD LOOKS RATHER ACTIVE. DIFLUENT FLOW SHOULD BE
IN PLACE OVER THE AREA AT THE START OF THIS PERIOD...AHEAD OF A
CLOSED LOW IN SRN WY. WED COULD ALSO BE AN ACTIVE DAY WITH STORMS
BUT WITH FAIRLY WIDESPREAD CLOUDS AND PCPN SVR POTENTIAL IS NOT
CLEAR. IT DOES APPEAR THAT WE WILL DRY OUT THU INTO THU NGT...BUT
RAIN CHANCES SHOULD RETURN FRI AND PROBABLY LAST INTO THE WEEKEND.
&&
.AVIATION...(12Z TAFS FOR KOMA...KLNK...KOFK THROUGH 12Z MONDAY)
ISSUED AT 612 AM CDT SUN APR 24 2016
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO MOVE THROUGH
KOMA AND KLNK THIS MORNING. VFR CONDITIONS ARE EXPECTED AFTER
14-15Z UNTIL THUNDERSTORMS BEGIN TO BLOSSOM AND MOVE EAST ACROSS
THE REGION MID AFTERNOON...SOME OF WHICH COULD BE SEVERE.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...KERN
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
916 AM CDT SUN APR 24 2016
.DISCUSSION...BROWNSVILLE RADAR SHOWS THE LARGE AREA OF
SHOWERS AND THUNDERSTORMS MOVING EAST OF THE LOWER TEXAS GULF
WATERS THIS MORNING. THE ATMOSPHERE HAS STABILIZED ACROSS MUCH OF
DEEP SOUTH TEXAS THIS MORNING IN THE WAKE OF THE OVERNIGHT
CONVECTION. THE COMBINATION OF THE APPROACHING UPPER LEVEL
DISTURBANCE...DAYTIME HEATING AND THE MOIST AIR MASS IN PLACE
WILL SUPPORT THE DEVELOPMENT OF CONVECTION THIS AFTERNOON. THE
STORM PREDICTION CENTER /SPC/ CONTINUES TO HAVE MOST OF DEEP SOUTH
TEXAS UNDER A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR TODAY.
MADE A QUICK UPDATE TO LOWER POPS FOR THIS MORNING AND MADE SOME
MINOR ADJUSTMENTS TO THE POP AND QPF GRIDS. NO OTHER CHANGES
NEEDED.
&&
.PREV DISCUSSION... /ISSUED 639 AM CDT SUN APR 24 2016/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...CEILINGS HAVE TEMPORARILY LIFTED...BUT THE MID LEVEL
DISTURBANCE MOVING OVER CENTRAL TEXAS MAY HAVE A BIT OF ENERGY
LEFT IN IT...WITH MVFR CEILINGS BUILT INTO THE TAFS FOR A FEW
HOURS FROM MID MORNING TO MID AFTERNOON...WITH ANY REMAINING
RESIDUAL RAIN CHANCES. VFR TAFS OTHERWISE UNTIL LATE TONIGHT.
WINDS WILL REMAIN LIGHT TO MODERATE SOUTHEAST.
PREV DISCUSSION... /ISSUED 428 AM CDT SUN APR 24 2016/
SHORT TERM /NOW THROUGH MONDAY/...A MID LEVEL SHORT WAVE TROUGH
WILL TRUNDLE ACROSS SOUTH CENTRAL TEXAS TODAY AND...WITH DAYTIME
HEATING...HAS PROMPTED A MARGINAL RISK OF SVR WEATHER CATEGORIZATION
FROM SPC. THE MAIN THREAT TODAY...AS SCATTERED THUNDERSTORMS DEVELOP
AND MOVE ACROSS THE AREA...WILL BE STRONG WIND GUSTS...FREQUENT
LIGHTNING...SMALL HAIL AND BRIEF HEAVY DOWNPOURS.
A ROUND OF SHOWERS AND THUNDERSTORMS HAS ALREADY MOVED THROUGH THE
AREA THIS MORNING...CONFIRMING THE THREAT FOR LIGHTNING...BRIEF
DOWNPOURS AND GUSTY WINDS...BUT RADAR ALSO SHOWS MORE DEVELOPMENT
TO THE SOUTH...AND THERE IS NO REASON TO BELIEVE THAT SOME
CONVECTION WILL NOT KEEP COMING THROUGH THE DAY. THE HRRR AND NAM
SHOW SOME QPF OVER EASTERN SECTIONS.
CONVECTION SHOULD END THIS EVENING...EXCEPT POSSIBLY FOR THE MARINE
AREAS...WITH IMPROVING CONDITIONS. LOOK FOR MODERATE SOUTHEAST WINDS
AND A MIX OF CLOUDS AND SUN ON MONDAY. HIGH TEMPS WILL RANGE FROM
THE 80S AT THE COAST TO THE UPPER 90S FAR WEST.
LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...THE ONLY OPPORTUNITY
FOR PRECIPITATION DURING THE LONG TERM PORTION OF THE FORECAST
WILL OCCUR ON WEDNESDAY...AS THE INTRUSION OF A WEAK COLD FRONT
INTO DEEP SOUTH TEXAS AND THE RIO GRANDE VALLEY COMBINES WITH
DECENT AVAILABLE MOISTURE AND DAYTIME HEATING TO PRODUCE ISOLATED
SHOWERS AND THUNDERSTORMS. THE REMAINDER OF THE FORECAST WILL BE
DRY WITH NO OTHER COLD FRONT PASSAGES OR SIGNIFICANT DISTURBANCES
AT THE 500 MB LEVEL. MAINLY PARTLY CLOUDY SKIES WILL SUPPORT WELL
ABOVE NORMAL DAYTIME HIGH AND OVERNIGHT LOW TEMPERATURES.
MARINE...NOW THROUGH MONDAY...LIGHT SOUTHEAST WINDS WILL INCREASE
TO HIGH END MODERATE THIS AFTERNOON AS HIGH PRESSURE OVER THE
NORTHWEST GULF INTERACTS WITH LOWER PRESSURE OVER THE HIGH PLAINS.
MODERATE WINDS WILL CONTINUE TONIGHT AND SEAS WILL BUILD...WITH
POSSIBLE SMALL CRAFT SHOULD EXERCISE CAUTION CONDITIONS. HIGH END
MODERATE WINDS WILL REPEAT ON MONDAY. SHOWERS AND THUNDERSTORMS
WILL BE POSSIBLE TODAY AS AN UPPER DISTURBANCE INFLUENCES THE
AREA.
MONDAY NIGHT THROUGH SATURDAY...SMALL CRAFT EXERCISE CAUTION
AND SMALL CRAFT ADVISORY WILL DOMINATE THROUGHOUT THE LONG
TERM PORTION OF THE MARINE FORECAST...WITH HIGH PRESSURE OVER
THE GULF OF MEXICO INTERACTING WITH LOWER PRESSURE INLAND.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
63
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
639 AM CDT SUN APR 24 2016
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...CEILINGS HAVE TEMPORARILY LIFTED...BUT THE MID LEVEL
DISTURBANCE MOVING OVER CENTRAL TEXAS MAY HAVE A BIT OF ENERGY
LEFT IN IT...WITH MVFR CEILINGS BUILT INTO THE TAFS FOR A FEW
HOURS FROM MID MORNING TO MID AFTERNOON...WITH ANY REMAINING
RESIDUAL RAIN CHANCES. VFR TAFS OTHERWISE UNTIL LATE TONIGHT.
WINDS WILL REMAIN LIGHT TO MODERATE SOUTHEAST.
&&
.PREV DISCUSSION... /ISSUED 428 AM CDT SUN APR 24 2016/
SHORT TERM /NOW THROUGH MONDAY/...A MID LEVEL SHORT WAVE TROUGH
WILL TRUNDLE ACROSS SOUTH CENTRAL TEXAS TODAY AND...WITH DAYTIME
HEATING...HAS PROMPTED A MARGINAL RISK OF SVR WEATHER CATEGORIZATION
FROM SPC. THE MAIN THREAT TODAY...AS SCATTERED THUNDERSTORMS DEVELOP
AND MOVE ACROSS THE AREA...WILL BE STRONG WIND GUSTS...FREQUENT
LIGHTNING...SMALL HAIL AND BRIEF HEAVY DOWNPOURS.
A ROUND OF SHOWERS AND THUNDERSTORMS HAS ALREADY MOVED THROUGH THE
AREA THIS MORNING...CONFIRMING THE THREAT FOR LIGHTNING...BRIEF
DOWNPOURS AND GUSTY WINDS...BUT RADAR ALSO SHOWS MORE DEVELOPMENT TO
THE SOUTH...AND THERE IS NO REASON TO BELIEVE THAT SOME CONVECTION
WILL NOT KEEP COMING THROUGH THE DAY. THE HRRR AND NAM SHOW SOME QPF
OVER EASTERN SECTIONS.
CONVECTION SHOULD END THIS EVENING...EXCEPT POSSIBLY FOR THE MARINE
AREAS...WITH IMPROVING CONDITIONS. LOOK FOR MODERATE SOUTHEAST WINDS
AND A MIX OF CLOUDS AND SUN ON MONDAY. HIGH TEMPS WILL RANGE FROM
THE 80S AT THE COAST TO THE UPPER 90S FAR WEST.
LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...THE ONLY OPPORTUNITY
FOR PRECIPITATION DURING THE LONG TERM PORTION OF THE FORECAST
WILL OCCUR ON WEDNESDAY...AS THE INTRUSION OF A WEAK COLD FRONT
INTO DEEP SOUTH TEXAS AND THE RIO GRANDE VALLEY COMBINES WITH
DECENT AVAILABLE MOISTURE AND DAYTIME HEATING TO PRODUCE ISOLATED
SHOWERS AND THUNDERSTORMS. THE REMAINDER OF THE FORECAST WILL BE
DRY WITH NO OTHER COLD FRONT PASSAGES OR SIGNIFICANT DISTURBANCES
AT THE 500 MB LEVEL. MAINLY PARTLY CLOUDY SKIES WILL SUPPORT WELL
ABOVE NORMAL DAYTIME HIGH AND OVERNIGHT LOW TEMPERATURES.
MARINE...NOW THROUGH MONDAY...LIGHT SOUTHEAST WINDS WILL INCREASE
TO HIGH END MODERATE THIS AFTERNOON AS HIGH PRESSURE OVER THE
NORTHWEST GULF INTERACTS WITH LOWER PRESSURE OVER THE HIGH PLAINS.
MODERATE WINDS WILL CONTINUE TONIGHT AND SEAS WILL BUILD...WITH
POSSIBLE SMALL CRAFT SHOULD EXERCISE CAUTION CONDITIONS. HIGH END
MODERATE WINDS WILL REPEAT ON MONDAY. SHOWERS AND THUNDERSTORMS
WILL BE POSSIBLE TODAY AS AN UPPER DISTURBANCE INFLUENCES THE
AREA.
MONDAY NIGHT THROUGH SATURDAY...SMALL CRAFT EXERCISE CAUTION
AND SMALL CRAFT ADVISORY WILL DOMINATE THROUGHOUT THE LONG
TERM PORTION OF THE MARINE FORECAST...WITH HIGH PRESSURE OVER
THE GULF OF MEXICO INTERACTING WITH LOWER PRESSURE INLAND.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
54/66/65
AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
239 PM PDT SUN APR 24 2016
.SYNOPSIS...
Gusty northwest winds will continue over much of the area through
monday. Temperatures will fluctuate from day to day through
Tuesday. Low pressure approaching from the northwest will bring
cooler weather and possible showers Wednesday and Thursday.
warmer conditions to quickly follow Friday through the weekend.
&&
.SHORT TERM...(TDY-TUE)
The dry front is moving through Los Angeles County this
afternoon. Colder air behind the front will tap into the 100 KT
jet aloft and produce northwest winds tonight through Monday
night...with Monday bringing the strongest and most widespread
winds overall. Wind advisories cover much of the area...and even
those not under a wind advisory will see breezy conditions at
times. With the strongest winds around Point Conception and the
nam showing 55 KT at 850 MB...went ahead and issued a high wind
warning for Santa Rosa and San Miguel Islands for tonight. These
winds will also push winds up against the northern slopes later
tonight and some light showers are likely. Snow levels will lower
through the night and should settle down near 5000 feet. There is
a 10 percent chance that the snow levels come in low enough to
produce a light snow shower over the Tejon Pass/Grapevine
area...but it should not stick.
Temperatures have peaked early today...tipping Monday`s cooling
hand. While the sharpest cooling will be over interior areas...all
areas should be noticeably cooler.
While the winds should weaken below advisory thresholds quickly
monday night...they will shift and become north to northeasterly
by tuesday morning. This will combine with a ridge of high
pressure nosing in from the west to produce noticeable warming.
Temperatures should push back to above normal in most
locations...and return to similar numbers as today.
Energy from a large low pressure system currently south of the
Aleutian Islands will break off and form a new system that will
settle into eastern California Wednesday and Thursday. Small
variations in this track will have large ramifications with the
outcome teetering on cold, rain, and thunderstorms...or dry and
windy. The current projections split this difference...but the
spread in the ensembles show that this track is still anything but
settled and run-to-run variations should be expected. Spread out
the chances of rain in time to account for the range of potential
tracks...with rain possible anytime on wednesday and/or Thursday.
while the current projected track supports a slight chance of
Thunderstorms in the forecast...will wait for another day before
adding them.
.LONG TERM...(WED-SAT)
Fairly confident that the low will move out of the area to the
east as both the GFS and ECMWF continue to sing in harmony. A
large 585 DM ridge of high pressure will then push in from the
west and onshore flow will be weak. Temperatures look poised to
soar by the weekend...with temperatures generally in the 80s
likely...and some 90s are possible.
&&
.AVIATION...24/1800Z...
Mid/upper level trough of low pressure over the area will shift
east as a ridge of high pressure upstream approaches the area.
Upper level strong southwest winds will become strong west by 24/23z
and strong northwest after 25/12z while mid level light to
moderate west-northwest winds become moderate to strong northwest
after 25/04z. Decreasing mid/upper level moisture after 24/22z.
Mixed moderate onshore and northerly pressure gradient through
25/04z and after 25/19z otherwise moderate northerly gradient.
marine inversion was south and west of the area and will differ
little Monday morning.
Marine layer at LAX at 1700Z is none.
KLAX...Decreasing mid/upper level cloud field after 24/21z.
Moderate onshore surface winds between 25/03-25/13z and after
25/18z.
KBUR...Decreasing mid/upper level cloud field after 24/21z. low
level north winds likely after 25/13z.
virtually certain - 95-100%
very likely - 80-95%
likely - 60-80%
chance - 30-60%
very unlikely - 20% OR LESS
&&
.MARINE...24/200 pM...
Northwest winds will likely increase through tonight over the
entire area and a gale warning is in effect through Monday night.
Northwest winds will diminish Monday night and are expected to
increase Tuesday afternoon and it is likely small craft advisory
conditions with gale gusts will exist from Piedras Blancas to San
Clemente Island including the west portion of the Santa Barbara
Basin through Thursday. Otherwise swells from a distant storm will
continue to subside but seas will build locally and become very
steep through Monday. A storm force wind fetch developed in the
Southern Ocean and oriented 200-180 degrees to Ventura County
overnight and swells originating from the fetch will begin to
arrive next week Saturday and probably generate hazardous surf and
extra currents and surging along exposed south facing shores
Saturday through Monday.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...High Surf Advisory in effect until 5 PM PDT Tuesday For zones
34-35. (See LAXCFWLOX).
Wind Advisory in effect until 9 PM PDT this evening For zones
34>36. (See LAXNPWLOX).
Beach Hazards Statement in effect through late Monday night
For zones 39>41-87. (See LAXCFWLOX).
Wind Advisory in effect until 3 AM PDT Tuesday For zones
39-52>54-59. (See LAXNPWLOX).
Wind Advisory in effect from noon to 9 PM PDT Monday For
zones 40-41. (See LAXNPWLOX).
Wind Advisory in effect until 9 PM PDT Monday For zone 87. (See LAXNPWLOX).
High Wind Warning in effect until 6 AM PDT Monday For zone
549. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 3 PM PDT this afternoon
For zones 645-670. (See LAXMWWLOX).
Gale Warning in effect until 5 AM PDT Tuesday For zones
645-670-673-676. (See LAXMWWLOX).
Small Craft Advisory in effect until 8 PM PDT this evening
For zones 650-655. (See LAXMWWLOX).
Gale Warning in effect from 8 PM this evening to 9 PM PDT
Monday For zones 650-655. (See LAXMWWLOX).
&&
$$
PUBLIC...Kittell
AVIATION...30
MARINE...30
SYNOPSIS...Kittell
weather.gov/losangeles
[top]
Area Forecast Discussion
National Weather Service Reno NV
231 PM PDT SUN APR 24 2016
.SYNOPSIS...
Low pressure will move through western Nevada tonight and Monday.
Light snow is expected near the Oregon Border tonight while most
locations see a few showers and brisk northwest winds. After a
break Tuesday, unsettled weather returns for Wednesday and
Thursday. A warming trend with dry weather is looking more likely
for next weekend.
&&
.SHORT TERM...
Scattered showers have developed across Northeast California and
Western NV this afternoon and will continue into the evening. With
the cloud cover, instability has not been as great as anticipated,
but a few thunderstorms remain possible through sunset. Localized
rainfall amounts up to 1/3" are possible in the heaviest showers.
Snow levels are running around 6000 feet into this evening, but
will drop as the cold upper low moves in.
Overnight and into Monday, have made a few adjustments based on
latest trends and model forecasts. The main adjustments were to
increase the precip chances north of a Susanville-Lovelock line
and increase winds a bit more Monday afternoon. With the upper low
diving into Western NV tonight, the GFS, HRRR and EC all show an
area of deformation setting up from Austin, NV to Cedarville, CA.
QPF amounts are averaging 1/4" to 1/2" in this band. Snow levels
are expected to drop to near 4000-4500 feet. Issued a winter
weather advisory for light snow amounts near the Oregon Border
where it is more likely to stick to roads as they will be in the
cold air longer.
Monday morning that band dissipates as the upper low moves into
southern NV. The low is moving through a little faster and will
take the upper cold pool with it resulting in more stabilization.
Still expect some showers in the afternoon, but they are looking
more likely to be confined to areas south of highway 50. It still
looks quite cool, and a brisk NW wind of 15-25 mph with higher
gusts will make it feel colder. With these winds aligned with
Pyramid Lake, issued a Lake Wind Advisory there.
Monday night and Tuesday will see quiet weather under a short wave
ridge. Then the next upper low is expected to arrive Tuesday night
into Wednesday. This one will not be quite as cold, although it
will have some moisture. Forcing also does not look overly strong,
so at this point we are expecting showers again with a few
thunderstorms possible. Wallmann
.LONG TERM...Thursday through Sunday...
Active weather continues late next week as mean upper level
troughing remains fixed over the Western United States. Low
pressure that will move into the region Wednesday will slowly exit
into the Inter-Mountain West Friday night into Saturday. Snow
levels remain around 6000-7000 feet through Friday before rising
7000-8000 feet over the weekend. Kept mention of thunderstorms for
Thursday afternoon since sufficient instability remains.
Models have changed a little from previous runs for Saturday and
Sunday. Previously, deterministic runs were showing another low
dropping into the backside of the trough impacting Western Nevada
and the Sierra. Now, deterministic runs and ensembles are favoring
a more eastward track with low pressure pushing through Eastern
Nevada and Utah. As a result, have begun to back off of
precipitation chances over the weekend. Correspondingly, have
increased daily highs for the weekend as well with temperatures
approaching 70 degrees for Western Nevada Valleys. Boyd
&&
.AVIATION...
Low pressure will continue to impact the region this afternoon
into Monday at all terminals. Expect periods of IFR/MVFR in the
Sierra by Monday morning with periods of snow. MVFR conditions
will be possible for Sierra Front with snow levels dragging down
to around 4500 feet. It is possible that there could be periods of
IFR and light rain/snow mix at KRNO and KCXP Monday morning as
well. However, surface temperatures for Sierra Front terminals
will be too warm to allow for much/any snow to stick on the
tarmac.
Winds will increase with gusts generally up to 30 knots for
Sierra Front terminals while winds at KTVL/KTRK being lighter due
to precipitation influences. KMMH may see a few intermittent gusts
up to 40 knots Monday. Boyd/Hoon
&&
.REV Watches/Warnings/Advisories...
NV...Lake Wind Advisory from 6 AM to 8 PM PDT Monday for Pyramid Lake
in NVZ004.
Winter Weather Advisory from 8 PM this evening to 8 AM PDT
Monday NVZ005.
CA...Winter Weather Advisory from 8 PM this evening to 8 AM PDT
Monday CAZ070.
&&
$$
For more information from the National Weather Service visit...
http://weather.gov/reno
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
305 PM MDT SUN APR 24 2016
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 214 PM MDT SUN APR 24 2016
FOR TONIGHT...THE UPPER TROUGH OVER THE NEBRASKA PANHANDLE WILL
CONTINUE TO LIFT TO THE NORTHEAST. LINGERING WRAP AROUND MOISTURE
WILL DIMINISH OVER THE NORTHEAST PLAINS BY THIS EVENING. DOWNWARD
QG DESCENT/SUBSIDENCE WILL CONTINUE THROUGH THIS EVENING. NAM12
SPATIAL CROSS-SECTIONS SHOW THE MOISTURE WEST OF THE CONTINENTAL
DIVIDE DECREASING THIS EVENING SO LIGHT SNOW SHOULD COME TO AN END
AS WELL. GUSTY WEST/NORTHWEST WINDS WILL LINGER THROUGH THIS
AFTERNOON BUT WILL DECREASE AS WELL AFTER 00Z. LATE TONIGHT... AN
UPPER LEVEL RIDGE OF HIGH PRESSURE WILL MOVE OVER THE CWA. THE
RIDGE AXIS WILL SLIDE TO THE EAST BY 18Z MONDAY. AN INCREASING
SOUTHWESTERLY FLOW WILL OCCUR AHEAD OF THE NEXT PACIFIC SYSTEM
WHICH WILL DROP INTO THE GREAT BASIN REGION MONDAY AFTERNOON. IN
THE MOUNTAINS...MID LEVEL MOISTURE WILL INCREASE COUPLED WITH WEAK
QG ASCENT AND AFTERNOON INSTABILITY TO PRODUCE A MIX OF RAIN/SNOW
SHOWERS ALONG WITH A FEW TSTMS. ACROSS THE NORTHEAST
PLAINS...SOUTHEASTERLY SFC WINDS WILL INCREASE IN THE AFTN WHICH
SHOULD PRODUCE A DENVER CYCLONE. NAM12 FORECAST SOUNDINGS HAVE AN
INVERTED-V PROFILE WITH CAPES AROUND 500 J/KG. GUSTY OUTFLOW WINDS
WILL BE THE MAIN ISSUE AT LEAST THROUGH THE AFTERNOON,
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 214 PM MDT SUN APR 24 2016
...COOLER AND UNSETTLED WEATHER THROUGH NEXT WEEKEND...
SHOWERS AND THUNDERSTORMS SHOULD BECOME MORE NUMEROUS OVER THE
FORECAST AREA THROUGH MONDAY EVENING AS SYNOPTIC SCALE Q-G LIFT
INCREASES AHEAD OF UPPER LOW MOVING EAST THROUGH UTAH. THE MODELS
HAVE COME INTO GOOD AGREEMENT WITH THE UPPER LOW MOVING
EAST/NORTHEAST FROM THERE INTO WESTERN COLORADO LATE MONDAY NIGHT
AND THEN ACROSS ROUGHLY THE FORT COLLINS-CHEYENNE AREA BY TUESDAY
MORNING. HOWEVER...IT SHOULD BE NOTED THE STORM SYSTEM HAS YET TO
MOVE ONSHORE AND THESE TYPES OF LOWS CAN TYPICALLY DIG MORE THAN
ADVERTISED...SO WILL CONTINUE TO WATCH FOR A FARTHER SOUTH TRACK.
AS A RESULT...WILL KEEP POPS RELATIVELY HIGH THROUGH THIS PERIOD
DESPITE THE THREAT OF A DRY SLOT. EVEN IF THE STORM KICKS OUT A
BIT FARTHER TO THE NORTH COULD STILL SEE CONVECTIVE SHOWERS AND
STORMS CONTINUE THROUGH THE NIGHT INTO TUESDAY GIVEN THE
INSTABILITY AND POTENTIAL FOR WEAK UPSLOPE BEHIND A FRONTAL
SURGE. SNOW LEVEL WILL EVENTUALLY FALL THROUGH THE FOOTHILLS AND
WE COULD EVEN SEE A MIX OF RAIN/SNOW DOWN INTO THE I-25 CORRIDOR
BY TUESDAY NIGHT AS COLD AIR MOVES IN ON THE BACK SIDE OF THIS
LOW. AT THIS TIME...MOST OF THE ACCUMULATING SNOWFALL SHOULD OCCUR
ABOVE 8000-9000 FEET WHERE SEVERAL INCHES POSSIBLE THROUGH TUESDAY
NIGHT. IF THE STORM DOES DROP FARTHER SOUTH...THEN NORTHERN
FOOTHILLS WOULD HAVE A HIGHER CHANCE OF ACCUMULATING SNOWFALL AS
WELL.
BY WEDNESDAY...UPPER LEVEL RIDGE OCCURS BUT STILL SOME MOISTURE
AROUND TO KEEP A LOW THREAT OF SHOWERS IN THE FORECAST. MOST OF
THE PLAINS SHOULD BE TOO STABLE TO SUPPORT ANY PRECIP SO WILL KEEP
MOST OF THE POPS CONFINED TO THE MOUNTAINS.
THE NEXT STORM SYSTEM WILL THEN BEGIN TO AFFECT THE AREA BY
THURSDAY WITH INCREASING CHANCE OF SHOWERS AND THUNDERSTORMS. THE
LAST COUPLE MODEL RUNS AND ENSEMBLES KEEP THE TRACK OF THIS STORM
A BIT FURTHER SOUTH SO OVERALL PRECIPITATION AMOUNTS WOULD LIKELY
BE HIGHER...AND MOST OF THAT FALLING IN SNOW OVER THE HIGHER
FOOTHILLS AND MOUNTAINS. THAT STORM SYSTEM SHOULD KICK TO THE EAST
BY SATURDAY BUT ANOTHER DISTURBANCE IS ADVERTISED TO QUICKLY FILL
IN BEHIND BY SUNDAY. DAYTIME HIGHS APPEAR TO AVERAGE A GOOD 10
DEGREES BELOW NORMAL FOR THE LATTER HALF OF THIS WEEK THROUGH NEXT
WEEKEND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 214 PM MDT SUN APR 24 2016
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. NORTHWEST WINDS
EXPECTED TO CONTINUE UNTIL 00-01Z...THEN THE HRRR MDLS SHOWS A
WEAK NNELY PUSH EARLY THIS EVENING...WHICH THEN TRANSITION A
SOUTHERLY DRAINAGE BY LATE EVENING. TRENDED THE LAST SET OF TAFS
BASED ON THIS MDL. FOR MONDAY...SFC WINDS BECOME SELY IN THE LATE
MORNING/AFTN WHICH WILL INDUCE A DENVER CYCLONE. INVERTED-V
SOUNDINGS IN THE AFTERNOON...SO PRIMARY CONCERN WITH ANY
DEVELOPING STORM WILL BE GUSTY OUTFLOW WINDS...35-40 KTS. STILL
THINK CIGS WILL REMAIN HIGH ENOUGH TO AVOID ANY RESTRICTIONS IN
THE AFTERNOON.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...COOPER
LONG TERM...BARJENBRUCH
AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
437 PM EDT SUN APR 24 2016
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 437 PM EDT SUN APR 24 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW CONFLUENT WNW FLOW OVER
THE UPPER GREAT LAKES BTWN A NRN STREAM TROF OVER SE CANADA INTO NEW
ENGLAND AND LOW AMPLITUDE SRN STREAM RIDGING OVER THE MISSISSIPPI
VALLEY AHEAD OF A MID LEVEL LOW CENTERED NEAR RAPID CITY. COLD AIR
THAT HAS EXPANDED UNDER THE SE CANADA TROF AND WARM AIR PUSHING INTO
THE UPPER MISSISSIPPI VALLEY AHEAD OF SRN STREAM MID LEVEL LOW HAS
RESULTED IN A TIGHTENING THERMAL GRADIENT/BAROCLINIC ZONE ACROSS THE
UPPER MISSISSIPPI VALLEY/GREAT LAKES. PER 12Z RAOBS...850MB TEMPS
RANGED FROM -16C AT MOOSONEE TO -10C AT PICKLE LAKE TO 14C AT THE
TWIN CITIES. UPPER DIVERGENCE IN RIGHT ENTRANCE OF 120+KT UPPER JET
EXTENDING ACROSS NRN ONTARIO INTO SRN QUEBEC IS AIDING PCPN
DEVELOPMENT WITHIN THE BAROCLINIC ZONE OVER THE UPPER MISSISSIPPI
VALLEY INTO THE WRN GREAT LAKES. HOWEVER...PCPN TODAY HAS BEEN
DISPLACED FARTHER SW THAN INDICATED BY THE MODELS YESTERDAY. THIS IS
ESPECIALLY TRUE OF THE MDT/HEAVY PCPN WHICH HAS STAYED SW AND S OF
THE WI/MI BORDER. ALL DAY...RADAR IMAGERY LOOP HAS SHOWED PCPN
DEVELOPMENT BEING FOCUSED CLOSER TO THE SFC FRONTAL BOUNDARY ACROSS
SRN MN TO ECNTRL WI. AS A RESULT...MEANINGFUL 850/700MB MOISTURE
TRANSPORT HAS NOT ABLE TO EXTEND NE INTO UPPER MI. THUS...PCPN
AMOUNTS TODAY HAVE BEEN MUCH LESS THAN ANTICIPATED.
TONIGHT...INFLUENCE OF THE SE CANADA TROF IS FCST TO RELAX
SOME...ALLOWING MID LEVEL LOW OVER THE WRN PLAINS TO SHIFT E TO ERN
SD/SW MN. PROGRESSION OF THESE FEATURES SHOULD ALLOW BETTER MOISTURE
TRANSPORT/LOW-MID LEVEL FGEN TO SHIFT NE INTO UPPER MI. UPPER
DIVERGENCE IN RIGHT ENTRANCE OF UPPER JET ALSO BECOMES MORE
FAVORABLY POSITIONED OVER THE AREA. AS A RESULT...EXPECT
STEADIER/HEAVIER RAIN TO LIFT NE INTO THE FCST AREA TONIGHT.
HOWEVER...GIVEN RECENT MODEL PERFORMANCE IN BEING TOO AGGRESSIVE
LIFTING PCPN N...WOULD NOT BE SURPRISED IF THE HEAVIER PCPN
STRUGGLES TO SPREAD NE INTO THE FCST AREA.
ON MON...REMNANT OF THE MID LEVEL LOW THAT WILL BE OVER ERN SD/SW MN
MON MORNING WILL RAPIDLY WEAKEN AS IT SHEARS EASTWARD INTO THE
CONFLUENT FLOW OVER THE UPPER LAKES. ALTHOUGH WEAKENING...INCREASING
DEEP LAYER FORCING PER QVECTORS AND LINGERING FGEN WILL KEEP PERIODS
OF RAIN GOING THRU THE DAY. MAY SEE A BREAK OR A PERIOD OF
DIMINISHED RAINFALL LATE TONIGHT/MON MORNING...ESPECIALLY ACROSS THE
S...BEFORE DEEP LAYER FORCING INCREASES.
SINCE RAINFALL TODAY WAS NOT NEARLY AS MUCH AS EXPECTED...DO NOT
ANTICIPATE ANY ISSUES WITH RAINFALL TONIGHT/MON. WILL PROBABLY STILL
SEE SOME PERIODS OF MDT/HVY RAINFALL...BUT AMOUNTS TONIGHT/MON ARE
NOW EXPECTED TO BE MOSTLY IN THE 1-2 INCH RANGE WHICH SHOULD NOT
POSE ANY WATER ISSUES.
MIN TEMPS TONIGHT WILL BE IN THE MID/UPPER 30S. WITH CLOUDS/FREQUENT
RAIN ON MON...FAVORED THE LOW END OF AVBL GUIDANCE. EXPECT HIGH
TEMPS IN THE UPPER 30S/LWR 40S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 PM EDT SUN APR 24 2016
SHORTWAVE MOVING THROUGH MON NIGHT WILL LEAD TO MAINLY RAIN...BUT
COLD AIR MOVING IN FROM THE N MAY TURN SOME PRECIP TO SNOW OVER NRN
UPPER MI. HOWEVER...PRECIP IS DIMINISHING AND MOVING OUT WHILE THE
COLDER AIR IS MOVING IN...SO ANY SNOWFALL AMOUNTS WILL BE LIGHT AND
SHOULD MAINLY BE ON GRASSY SURFACES.
TUE THROUGH NEXT SUN LOOKS COOL AND DRY AS CANADIAN HIGH PRESSURE
DOMINATES. 850MB TEMPS HOVERING A DEGREE OR TWO BELOW 0C WILL KEEP
HIGH TEMPS IN THE MID 40S TO MID 50S (MAYBE SOME UPPER 50S) AND WITH
PARTLY CLOUDY TO MOSTLY CLEAR SKIES...LOWS WILL BE NEAR TO BELOW
FREEZING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 148 PM EDT SUN APR 24 2016
WITH A STATIONARY FRONT REMAINING S OF UPPER MI THRU MON...EXPECT
PERIODS OF RAIN DURING THIS FCST PERIOD WITH CONDITIONS GENERALLY
SETTLING INTO THE IFR CATEGORY AT KIWD/KCMX/KSAW. BEST CHC OF
PREVAILING LIFR CONDITIONS WILL BE LATE TONIGHT/MON MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 437 PM EDT SUN APR 24 2016
WITH HIGH PRES BUILDING INTO NORTHERN ONTARIO AND WEAKENING LOW PRES
TRACKING E ALONG A STALLED FRONT S OF UPPER MI...STRONG E TO NE
WINDS WILL BE THE RULE ACROSS LAKE SUPERIOR THRU MON. OVER THE
WESTERN LAKE WHERE COASTAL CONVERGENCE/FUNNELING ENHANCE E TO NE
WINDS...GALE FORCE WINDS ARE EXPECTED THRU MON. STRONGEST WIND
GUSTS...POSSIBLY UP TO 45KT...WILL OCCUR MON AFTN. ACROSS THE REST
OF LAKE SUPERIOR...WINDS WILL STEADILY INCREASE FROM W TO E
TONIGHT...REACHING 20-30KT BY SUNRISE MON. WINDS WILL SLOWLY
DIMINISH MON NIGHT/TUE MORNING...BUT MORE SO TUE AFTN/NIGHT AS THE
NORTHERN ONTARIO HIGH PRES BUILDS INTO THE UPPER LAKES. E TO NE
WINDS GENERALLY UNDER 20KT WILL PREVAIL WED. GIVEN THE E TO NE WIND
DIRECTION...WINDS WILL BE STRONGEST OVER WRN LAKE SUPERIOR. WINDS
WILL REMAIN UNDER 20KT THU/FRI WITH HIGH PRES OVER THE AREA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 8 PM EDT /7 PM CDT/ MONDAY FOR LSZ162.
GALE WARNING FROM 5 AM TO 8 PM EDT MONDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
345 PM EDT SUN APR 24 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 424 AM EDT SUN APR 24 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW A CONFLUENT WNW
FLOW ALF OVER THE UPR LKS BTWN A NRN BRANCH CUTOFF LO OVER NRN
QUEBEC AND A SRN BRANCH FLOW DOMINATING THE CONUS WITH A STRONG
SHRTWV IN THIS FLOW DRIFTING SLOWLY ENEWD THRU WYOMING. THERE IS A
GOOD DEAL OF CLD COVER OVER UPR MI WITH WAA IN TIGHTENING BAROCLINIC
ZN TO THE NE OF H85 WARM FNT STRETCHING FM THE NRN PLAINS INTO WRN
WI...BUT AXIS OF HEAVIEST RA EARLY THIS MRNG STRETCHES FM NCENTRAL
MN ESEWD INTO NCENTRAL WI CLOSER TO THE H85 FNT. THERE ARE MORE SCT
RA SHOWERS DVLPG IN NRN MN WHERE UPR DVGC IN RRQ OF 120KT H3 JET
CORE CENTERED JUST SW OF JAMES BAY IS AIDING LIFT OF MOISTER AIR
SHOWN ON THE 00Z INL RAOB. LINGERING LLVL DRY AIR SHOWN ON THE 00Z
GRB/APX RAOBS THAT IS REPRESENTATIVE OF CONDITIONS OVER THE CWA HAS
SLOWED DOWN THE ARRIVAL OF THIS EXPANDING PCPN AND THE NE PUSH OF
THE RA IN WI CLOSER TO THE H85 WARM FNT. THE AIR IN ONTARIO IS EVEN
DRIER WITH 00Z PWAT AS LO AS 0.14 INCH AT YPL.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/QPF ASSOCIATED
WITH TIGHTENING BAROCLINIC ZN OVER UPR MI UNDER PERSISTENT UPR DVGC
IN RRQ OF H3 JET MAX MOVING ONLY SLOWLY E THRU TNGT. CLOSER APRCH
TNGT OF SHRTWV NOW IN WYOMING WILL INTENSIFY THE DYNAMIC SUPPORT.
CONFIDENCE IS INCRSG THE HEAVIER RA WL FALL NEAR THE WI BORDER...BUT
THERE ARE STILL SOME MODEL INCONSISTENCIES AS TO THE PLACEMENT OF
THE AXIS OF HEAVIER RA RELATED TO POSITION OF SHARPER FGEN AND
IMPACT OF DRY AIR TO THE N.
TDAY...H85 THERMAL GRADIENT/UPR DVGC IN RRQ OF UPR JET CORE TO THE
NE IS FCST TO EXPAND OVER UPR MI TODAY...AND MOST OF THE MODELS
SHIFT AXIS OF HEAVIER PCPN TO THE N ACCORDINGLY. SO WL EXPAND HIER
POPS NE THRU THE CWA EXCEPT OVER THE KEWEENAW...WHICH WL BE CLOSER
TO THE DEEPER DRY AIR JUST TO THE N. HOWEVER...WITH LINGERING LLVL
DRY AIR...FAVOR THE 00Z REGIONAL CNDN MODEL FCST. THIS MODEL SHOWS
THE HIER QPF REMAINING CLOSER TO THE WI BORDER WHERE EVEN THE 00Z
NAM SHOWS MORE PERSISTENT AXIS OF SHARPER H85-7 FGEN/UVV AND WHERE
PWAT IS FCST TO INCRS TO AOA 1 INCH /ABOUT 225 PCT OF NORMAL/. THIS
FCST IS ALSO MORE CONSISTENT WITH LOCATION OF AXIS OF HEAVIER RA FM
NCENTRAL MN INTO NCENTRAL WI EARLY THIS MRNG...THE LOCATION OF WHICH
MAY HINT AT A BNDRY WHICH MAY ACT TO INTERCEPT MSTR INFLOW. WITH THE
CLDS AND RA DVLPG...EXPECT WELL BLO NORMAL MAX TEMPS THAT WL LIKELY
STAY UNDER 40 AT SOME PLACES NEAR LK SUP.
TNGT...WITH SLOW APRCH OF SHRTWV FM THE WSW TNGT...UPR DVGC OVER AND
MSTR TRANSPORT INTO ARE FCST TO INCRS OVERNGT. SO EXPECT HEAVIER RA
TO EXPAND TO THE NE. THE CNDN MODEL STILL SEEMS TO BE ON THE RIGHT
TRACK SHOWING THE AXIS OF HEAVIER PCPN DIMINISHING A BIT WITH THE
SHIFT TO THE NE GIVEN PERSISTENT DRY AIR IN THAT DIRECTION THAT WILL
TEND TO SHARPEN THE NRN EDGE OF THE PCPN/HEAVIER RA. TOTAL RA THRU
12Z MON WL REACH AS MUCH AS 1.50 TO 2.00 INCHES NEAR THE WI BORDER.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 PM EDT SUN APR 24 2016
SHORTWAVE MOVING THROUGH MON NIGHT WILL LEAD TO MAINLY RAIN...BUT
COLD AIR MOVING IN FROM THE N MAY TURN SOME PRECIP TO SNOW OVER NRN
UPPER MI. HOWEVER...PRECIP IS DIMINISHING AND MOVING OUT WHILE THE
COLDER AIR IS MOVING IN...SO ANY SNOWFALL AMOUNTS WILL BE LIGHT AND
SHOULD MAINLY BE ON GRASSY SURFACES.
TUE THROUGH NEXT SUN LOOKS COOL AND DRY AS CANADIAN HIGH PRESSURE
DOMINATES. 850MB TEMPS HOVERING A DEGREE OR TWO BELOW 0C WILL KEEP
HIGH TEMPS IN THE MID 40S TO MID 50S (MAYBE SOME UPPER 50S) AND WITH
PARTLY CLOUDY TO MOSTLY CLEAR SKIES...LOWS WILL BE NEAR TO BELOW
FREEZING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 148 PM EDT SUN APR 24 2016
WITH A STATIONARY FRONT REMAINING S OF UPPER MI THRU MON...EXPECT
PERIODS OF RAIN DURING THIS FCST PERIOD WITH CONDITIONS GENERALLY
SETTLING INTO THE IFR CATEGORY AT KIWD/KCMX/KSAW. BEST CHC OF
PREVAILING LIFR CONDITIONS WILL BE LATE TONIGHT/MON MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 AM EDT SUN APR 24 2016
WITH TIGHTENING PRES GRADIENT BETWEEN HI PRES BUILDING INTO NORTHERN
ONTARIO AND A LO PRES MOVING E FROM THE PLAINS ALONG A STALLED LO
PRES TROUGH TO THE S...EXPECT NE WINDS INCREASING TO 25 TO 30 KTS
THRU MON. THE STRONGEST WINDS WILL BE OVER THE WESTERN LAKE...WHERE
GALES TO 35-40 KTS ARE FORECAST THIS AFTERNOON THRU MON WITH A
COASTLINE CONFIGURATION THAT WILL ACCENTUATE THE NE FLOW. EXPANDED
THE GALE WARNING FOR LSZ162 TO INCLUDE LSZ263 FOR LATE TONIGHT AND
MON. WINDS WILL GRADUALLY DIMINISH MON NIGHT THRU TUE AS A HI PRES
BUILDS INTO THE UPPER LAKES. N TO E WINDS GENERALLY UNDER 20 KTS WILL
THEN PREVAIL ON WED AND THU WITH A HI PRES RIDGE AXIS IN PLACE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 8 PM EDT /7 PM CDT/ MONDAY FOR LSZ162.
GALE WARNING FROM 5 AM TO 8 PM EDT MONDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
149 PM EDT SUN APR 24 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 424 AM EDT SUN APR 24 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW A CONFLUENT WNW
FLOW ALF OVER THE UPR LKS BTWN A NRN BRANCH CUTOFF LO OVER NRN
QUEBEC AND A SRN BRANCH FLOW DOMINATING THE CONUS WITH A STRONG
SHRTWV IN THIS FLOW DRIFTING SLOWLY ENEWD THRU WYOMING. THERE IS A
GOOD DEAL OF CLD COVER OVER UPR MI WITH WAA IN TIGHTENING BAROCLINIC
ZN TO THE NE OF H85 WARM FNT STRETCHING FM THE NRN PLAINS INTO WRN
WI...BUT AXIS OF HEAVIEST RA EARLY THIS MRNG STRETCHES FM NCENTRAL
MN ESEWD INTO NCENTRAL WI CLOSER TO THE H85 FNT. THERE ARE MORE SCT
RA SHOWERS DVLPG IN NRN MN WHERE UPR DVGC IN RRQ OF 120KT H3 JET
CORE CENTERED JUST SW OF JAMES BAY IS AIDING LIFT OF MOISTER AIR
SHOWN ON THE 00Z INL RAOB. LINGERING LLVL DRY AIR SHOWN ON THE 00Z
GRB/APX RAOBS THAT IS REPRESENTATIVE OF CONDITIONS OVER THE CWA HAS
SLOWED DOWN THE ARRIVAL OF THIS EXPANDING PCPN AND THE NE PUSH OF
THE RA IN WI CLOSER TO THE H85 WARM FNT. THE AIR IN ONTARIO IS EVEN
DRIER WITH 00Z PWAT AS LO AS 0.14 INCH AT YPL.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/QPF ASSOCIATED
WITH TIGHTENING BAROCLINIC ZN OVER UPR MI UNDER PERSISTENT UPR DVGC
IN RRQ OF H3 JET MAX MOVING ONLY SLOWLY E THRU TNGT. CLOSER APRCH
TNGT OF SHRTWV NOW IN WYOMING WILL INTENSIFY THE DYNAMIC SUPPORT.
CONFIDENCE IS INCRSG THE HEAVIER RA WL FALL NEAR THE WI BORDER...BUT
THERE ARE STILL SOME MODEL INCONSISTENCIES AS TO THE PLACEMENT OF
THE AXIS OF HEAVIER RA RELATED TO POSITION OF SHARPER FGEN AND
IMPACT OF DRY AIR TO THE N.
TDAY...H85 THERMAL GRADIENT/UPR DVGC IN RRQ OF UPR JET CORE TO THE
NE IS FCST TO EXPAND OVER UPR MI TODAY...AND MOST OF THE MODELS
SHIFT AXIS OF HEAVIER PCPN TO THE N ACCORDINGLY. SO WL EXPAND HIER
POPS NE THRU THE CWA EXCEPT OVER THE KEWEENAW...WHICH WL BE CLOSER
TO THE DEEPER DRY AIR JUST TO THE N. HOWEVER...WITH LINGERING LLVL
DRY AIR...FAVOR THE 00Z REGIONAL CNDN MODEL FCST. THIS MODEL SHOWS
THE HIER QPF REMAINING CLOSER TO THE WI BORDER WHERE EVEN THE 00Z
NAM SHOWS MORE PERSISTENT AXIS OF SHARPER H85-7 FGEN/UVV AND WHERE
PWAT IS FCST TO INCRS TO AOA 1 INCH /ABOUT 225 PCT OF NORMAL/. THIS
FCST IS ALSO MORE CONSISTENT WITH LOCATION OF AXIS OF HEAVIER RA FM
NCENTRAL MN INTO NCENTRAL WI EARLY THIS MRNG...THE LOCATION OF WHICH
MAY HINT AT A BNDRY WHICH MAY ACT TO INTERCEPT MSTR INFLOW. WITH THE
CLDS AND RA DVLPG...EXPECT WELL BLO NORMAL MAX TEMPS THAT WL LIKELY
STAY UNDER 40 AT SOME PLACES NEAR LK SUP.
TNGT...WITH SLOW APRCH OF SHRTWV FM THE WSW TNGT...UPR DVGC OVER AND
MSTR TRANSPORT INTO ARE FCST TO INCRS OVERNGT. SO EXPECT HEAVIER RA
TO EXPAND TO THE NE. THE CNDN MODEL STILL SEEMS TO BE ON THE RIGHT
TRACK SHOWING THE AXIS OF HEAVIER PCPN DIMINISHING A BIT WITH THE
SHIFT TO THE NE GIVEN PERSISTENT DRY AIR IN THAT DIRECTION THAT WILL
TEND TO SHARPEN THE NRN EDGE OF THE PCPN/HEAVIER RA. TOTAL RA THRU
12Z MON WL REACH AS MUCH AS 1.50 TO 2.00 INCHES NEAR THE WI BORDER.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 413 AM EDT SUN APR 24 2016
SHORTWAVE TROUGH LIFTING ACROSS THE NORTHERN PLAINS COMBINES WITH
SHARP H85 BAROCLINIC ZONE TO SUPPORT MODERATE PERHAPS HEAVY RAIN
MONDAY MORNING. SINCE STRONGEST H85 TEMP GRADIENT AND ASSOCIATED
FRONTOGENSIS REMAINS OVER SOUTHERN TIER OF UPR MICHIGAN...PERFER
MODEL SOLUTIONS THAT DIMINISH QPF AS IT LIFTS OVER NORTHERN TIER
OF CWA IN THE MORNING. GFS AND GEM-REGIONAL FIT INTO THAT CATEGORY.
QUITE A COOL AND DAMP DAY ON MON NO MATTER THE COVERAGE OF THE RAIN.
EXPECT CHILLY READINGS IN THE MID-UPR 30S NEAR LK SUPERIOR AND
ONLY AROUND 40 ELSEWHERE.
PRIMARY SHORTWAVE TROUGH ARRIVES OVER UPPER GREAT LAKES ON MONDAY
AFTN. JET STREAK ROUNDING BASE OF TROUGH AND SOME ELEVATED
INSTABILITY MAY RESULT IN TSRA POSSIBLY SNEAKING INTO SCNTRL CWA
LATE MONDAY AFTN INTO MONDAY EVENING. DID KEEP MENTION OF TSRA OUT
ATTM AS WITH SFC LOW PASSING BY SOUTH OF UPR MICHIGAN...WOULD EXPECT
BEST CHANCES FOR EVEN ELEVATED TSRA OVER EASTERN WI AND ON FARTHER
SOUTH. ARRIVAL OF THE SHORTWAVE TROUGH SHOULD BRING ANOTHER ROUND OF
RAIN TO MAINLY THE SOUTH AND SOUTH CENTRAL IN THE AFTN. COOLER AIR
WORKS ACROSS UPR MICHIGAN MON EVENING AS THE LOW OVER WI SLIDES
EAST. 1000-500MB/850-700MB THICKNESSES AND NAM/GFS SOUNDINGS
INDICATE POTENTIAL FOR SNOW TO BEGIN MIXING WITH RAIN OVER HIGHER
TERRAIN OF NW AND NCNTRL MON EVENING THEN SWITCH OVER TO SNOW
OVERNIGHT MON NIGHT. SINCE THE ARRIVAL OF THE COLD AIR TIMES OUT
WITH DIMINISHING PRECIPITATION...SNOW AMOUNTS MON NIGHT SHOULD STAY
LESS THAN AN INCH...MAINLY ON GRASSY SURFACES.
AFTER THE RAIN/SNOW TO SNOW MOVES OUT LATE MON NIGHT...LOOKS DRY
THROUGH THE REST OF THE WEEK AND INTO NEXT WEEKEND AS HIGH PRESSURE
BUILDS OVER HUDSON BAY AND PERSISTS. DRY EASTERLY FLOW SHOULD KEEP
UPPER MICHIGAN DRY. WITH THE EAST TO NORTHEAST WIND OFF THE HIGH
COOLEST READINGS DURING THE DAYTIME SHOULD BE NEAR LK SUPERIOR.
TEMPS THERE LIKELY WILL REMAIN SLIGHTLY BELOW NORMAL THROUGH THE
WEEK. INLAND TEMPS AND NEAR LK MICHIGAN SHOULD REACH TOWARD NORMAL
BY MID TO LATE WEEK WITH READINGS IN THE 50S TO NEAR 60 BY LATE IN
THE WEEK. INFLUENCE OF THE DRY HIGH PRESSURE SHOULD ALLOW TEMPS AT
NIGHT AWAY FROM THE GREAT LAKES TO FALL INTO THE 20S TO LOW 30S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 148 PM EDT SUN APR 24 2016
WITH A STATIONARY FRONT REMAINING S OF UPPER MI THRU MON...EXPECT
PERIODS OF RAIN DURING THIS FCST PERIOD WITH CONDITIONS GENERALLY
SETTLING INTO THE IFR CATEGORY AT KIWD/KCMX/KSAW. BEST CHC OF
PREVAILING LIFR CONDITIONS WILL BE LATE TONIGHT/MON MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 AM EDT SUN APR 24 2016
WITH TIGHTENING PRES GRADIENT BETWEEN HI PRES BUILDING INTO NORTHERN
ONTARIO AND A LO PRES MOVING E FROM THE PLAINS ALONG A STALLED LO
PRES TROUGH TO THE S...EXPECT NE WINDS INCREASING TO 25 TO 30 KTS
THRU MON. THE STRONGEST WINDS WILL BE OVER THE WESTERN LAKE...WHERE
GALES TO 35-40 KTS ARE FORECAST THIS AFTERNOON THRU MON WITH A
COASTLINE CONFIGURATION THAT WILL ACCENTUATE THE NE FLOW. EXPANDED
THE GALE WARNING FOR LSZ162 TO INCLUDE LSZ263 FOR LATE TONIGHT AND
MON. WINDS WILL GRADUALLY DIMINISH MON NIGHT THRU TUE AS A HI PRES
BUILDS INTO THE UPPER LAKES. N TO E WINDS GENERALLY UNDER 20 KTS WILL
THEN PREVAIL ON WED AND THU WITH A HI PRES RIDGE AXIS IN PLACE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 8 PM EDT /7 PM CDT/ MONDAY FOR LSZ162.
GALE WARNING FROM 5 AM TO 8 PM EDT MONDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
348 PM CDT SUN APR 24 2016
.SHORT TERM...(TONIGHT)
ISSUED AT 348 PM CDT SUN APR 24 2016
A STRONG LOW PRESSURE SYSTEM WAS OVER CENTRAL SOUTH DAKOTA AT MID
AFTERNOON. A NEARLY STATIONARY FRONT MEANDERED FROM THE LOW
THROUGH WEST CENTRAL MN TO THE SOUTHERN METRO TO SOUTH OF EAU
CLAIRE WHILE A COLD FRONT CURVED SOUTH FROM THE LOW THROUGH
EASTERN NEBRASKA. SOME SUNSHINE DID OCCUR EARLIER IN THE
AFTERNOON ACROSS SOUTHWEST MN THROUGH EASTERN NE AND WESTERN IA.
THIS AREA HAS BECOME QUITE UNSTABLE WITH STORM DEVELOPMENT ALREADY
IN PROGRESS ACROSS EASTERN NE. VARIOUS CAMS INDICATE FURTHER
STRENGTHENING OF THE STORMS IN EASTERN NE WHILE MOVING INTO NW IA
AND EVENTUALLY SOUTHWEST AND SOUTH CENTRAL MN THIS EVENING.
EFFECTIVE SHEAR IS BEST INTO EARLY THIS EVENING ACROSS OUR FAR
WEST CENTRAL AND SOUTHWEST MN COUNTIES. HENCE...A SEVERE STORM OR
TWO CAN NOT BE RULED OUT TO THE NORTH AND EAST OF THE CURRENT
SEVERE THUNDERSTORM WATCH WHICH ADJOINS OUR SOUTHWEST MN CWA.
CAPE BEGINS TO FADE QUICKLY AFTER 02Z ON THE HRRR WITH A DOWNWARD
TREND IN STORM INTENSITY EXPECTED. THE STORMS COULD BE GETTING
CLOSE TO THE SOUTHWEST METRO AT THAT TIME BUT IN A WEAKENING MODE.
SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE THROUGH THE NIGHT
AS THE LOW SLOWLY APPROACHES SOUTHWEST MN BY DAYBREAK MONDAY. THE
SHOWERS AND THUNDERSTORMS WILL BE EFFICIENT RAIN PRODUCERS. PW
VALUES WILL PEAK AROUND 1.4 INCHES ACROSS SOUTH CENTRAL MN THIS
EVENING WITH VALUES ELSEWHERE IN THE 1.2 TO 1.3 INCH RANGE. THIS
IS AT THE TOP OF OUR PW CLIMATOLOGY FOR LATE APRIL. THEREFORE A
QUICK INCH OF RAIN IS NOT OUT OF THE QUESTION. QPF GRIDS ARE
WIDESPREAD HALF TO ONE INCH. THERE WILL ALSO BE QUITE THE THERMAL
CONTRAST ACROSS THE FA OVERNIGHT WITH THE EAST- WEST BOUNDARY
ACROSS SOUTHERN MN. LOWS WILL RANGE FROM THE LOWER 40S ACROSS
CENTRAL MN TO NEAR 60 AT ALBERT LEA.
.LONG TERM...(MONDAY THROUGH SUNDAY)
ISSUED AT 348 PM CDT SUN APR 24 2016
AN ACTIVE SOUTHWEST FLOW PATTERN WILL BE IN PLACE THROUGH THE
WEEKEND ACROSS THE CENTRAL CONUS. THE RESULT WILL BE A WET AND
SOMEWHAT COOL PATTERN OVER THE NEXT 7 DAYS.
THE FIRST OF THREE ROBUST UPPER LOWS WILL PASS ACROSS MN AND INTO
WISCONSIN TOMORROW. AS MENTIONED IN THE DISCUSSION ABOVE...THUNDER
IS EXPECTED TONIGHT OUT AHEAD OF THIS LOW THAT IS ADVANCING ACROSS
THE DAKOTAS. TOMORROW THE UPPER LOW WILL PASS ACROSS MN BUT START
TO SHEAR OUT AS IT REACHES LAKE SUPERIOR TOMORROW NIGHT. THE SURFACE
LOW WILL TRACK JUST TO THE SOUTH FROM ROUGHLY REDWOOD FALLS...TO
SOMEWHERE BETWEEN MANKATO AND THE SOUTHERN TWIN CITES METRO...TO
AROUND LA CROSSE. THE WARM FRONT ASSOCIATED WITH THIS LOW WILL
BISECT THE FORECAST AREA AND ONCE AGAIN YIELD A PRONOUNCED NORTH-
SOUTH TEMPERATURE GRADIENT ACROSS MN AND WESTERN WI. THERE WILL
ONCE AGAIN BE WIDESPREAD SHOWERS ACROSS THE FORECAST AREA WITH THE
POTENTIAL FOR THUNDER ACROSS EASTERN MN AND WESTERN WI WHERE
FORECAST SOUNDINGS SHOW 200-800J/KG OF MUCAPE AND ENOUGH VERTICAL
WIND SHEAR TO SUPPORT WEAKLY ORGANIZED OR MULTICELL CONVECTION. A
STRONG CELL OR TWO CANNOT BE RULED OUT TOMORROW AFTERNOON IN
WI...ESPECIALLY GIVEN THE WARM FRONT IN THE VICINITY AND THE ADDED
VORTICITY DUE TO THE SURFACE LOW. IT SORT OF HAS THE LOOK OF A
LOW- TOPPED NON-SUPERCELL LANDSPOUT DAY.
THERE IS ANOTHER DEEP LOW EJECTING OUT OFF THE ROCKIES AND INTO THE
PLAINS ON TUESDAY. THE TROUGH WILL DIG IN A LITTLER FARTHER SOUTH
AND WRAP MUCH MORE MOISTURE NORTH ACROSS THE PLAINS. THIS IS SETTING
THE STAGE FOR SEVERE WEATHER IN STATES TO OUR SOUTH.
LOCALLY...WIDESPREAD MODERATE RAIN TO POTENTIALLY HEAVY RAIN AS THE
LOW SWINGS EAST/NORTHEAST AND MID-LEVEL FGEN TRANSLATES ACROSS THE
AREA. A THIRD TROUGH WILL MAKE ITS WAY INTO THE CENTRAL CONUS THIS
WEEKEND AND CONTINUES OUR CHANCE FOR SHOWERS AND STORMS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1237 PM CDT SUN APR 24 2016
A NEARLY STATIONARY FRONT STRETCHES FROM WEST CENTRAL MN THROUGH
THE SOUTH METRO TO SOUTH OF KEAU. THE BOUNDARY WILL SLIP SLOWLY
SOUTH THIS EVENING ALLOWING MVFR OR LOWER CEILINGS TO SETTLE
ACROSS ALL OF CENTRAL MN AND MUCH OF WEST CENTRAL WI. THE METRO
AREA WILL BE BORDERLINE THIS EVENING THEN TREND LOWER OVERNIGHT.
SHOWERS CHANCES EARLY THIS AFTERNOON WILL BE MOST NUMEROUS ACROSS
CENTRAL MN AND WEST CENTRAL WI WITH MORE ROBUST THUNDERSTORMS
DEVELOPING ACROSS WEST CENTRAL THROUGH SOUTH CENTRAL MN LATE IN
THE DAY AND PROGRESSING EASTWARD THIS EVENING. THE THUNDERSTORM
ACTIVITY WILL LIKELY WANE OVERNIGHT AND TURN INTO A LARGE AREA OF
SHOWERS/LIGHT RAIN WITH LESS THAN MVFR VISIBILITIES. MVFR OR LOWER
CEILINGS AND VISIBILITIES WILL OCCUR ON MONDAY ALONG WITH SHOWERS
AND ISOLATED THUNDERSTORMS AS A LOW PRESSURE SYSTEM MOVES SLOWLY
EASTWARD ACROSS THE TAF SITES. WINDS THIS AFTERNOON AND EVENING
WILL BE ENE AT 15-20 KNOTS NORTH OF THE BOUNDARY AND SSE 15-25
KNOTS SOUTH OF THE BOUNDARY. WIND SPEEDS WILL SLOWLY DIMINISH
TONIGHT.
KMSP...A FEW SHOWERS EARLY THIS AFTERNOON WITH MAINLY VFR
CONDITIONS. THUNDERSTORMS CHANCES LOOK HIGH THIS EVENING WITH A
TEMPO GROUP INSERTED. THEREAFTER...SHOWERS WILL DIMINISH FOR A
TIME BUT THEM PICK BACK UP LATE IN THE NIGHT AND FOR EARLY
MONDAY WITH IFR CONDITIONS LIKELY.
/OUTLOOK FOR KMSP/
MON...MVFR/IFR WITH -SHRA ISOLATED TSRA. WIND NE 10-15KTS.
TUE...VFR. WINDS E 10-15KTS.
WED...MVFR LATE IN THE DAY. SHRA LIKELY. WIND E 15-25KTS
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...RAH
LONG TERM...CLF
AVIATION...RAH
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
402 PM CDT SUN APR 24 2016
.Discussion...
Issued at 402 PM CDT SUN APR 24 2016
Short Term (Tonight through Tuesday):
Tonight: Thunderstorms have begun to develop across eastern Nebraska
and central Kansas along a dry line. These thunderstorms will
continue to shift slowly east late this afternoon into this evening.
Storms are developing in an area of 1500-2000J/kg of MUCAPE,and dew
points in the upper 50s to near 60. Consequently these storms will
have the potential to be severe. Large hail and damaging winds will
the main threat despite the fact that 0-6km bulk shear is currently
weak it is expected to increase during the evening hours. These
storms will move east toward the CWA this evening however, hi-res
models suggest they will be diminishing as they reach us but does
depict a quasi-linear mode of storms that will be capable of
producing strong to damaging winds across extreme northeastern
Kansas and northwest Missouri. Further south across eastern Kansas
and northern Missouri, storms will be weakened as they move into
more stable air. Storms will continue through midnight before they
diminish in the overnight hours.
Monday through Tuesday: The upper level system that is the catalyst
for tonight`s system will move into the upper Midwest and weaken.
The attendant cold front will sag into the area tomorrow morning.
this front will slowly sag through the CWA during the day. Weak
convergence and moderate instability of 1000-1500J/kg of CAPE south
of the front may be enough to spark convection south of the front
however lack of forcing may keep conditions quiet. Consequently,
have just slight chance POPs across the southern CWA. Monday night
the front will become stationary across the southern CWA or just
south of the CWA. During the overnight hours a 40-50kt SWly LLJ will
increase across eastern OK and nose into sern KS/swrn MO. This may
provide enough lift to over run the stationary boundary and allow
for thunderstorm development that would affect the southern CWA late
Monday night into Tuesday morning. Tuesday a vigorous upper level
trough will move from the central Rockies into the High Plains. An
associated cold front will move into the western Plains with a dry
line across central Kansas. This will be the system to watch during
the extended period as there is the potential for all mode of severe
weather with this system. However, outside of morning showers and
storms, the area looks to remain capped through the day keeping
conditions dry will highs in the mid 70s to lower 80s.
Tuesday night through Sunday:
There will be two system capable of producing severe weather in the
extended period. The first will come on Tuesday night into
Wednesday. Tuesday night the aforementioned upper level trough will
move into central Plains taking on a negative tilt as it does so. As
it does an embedded shortwave will rotate around the base of the
trough ushering in cooler air aloft and eroding the cap. This will
allow storms to develop along the aforementioned dryline in eastern
Kansas. With strong shear, instability and moisture all modes of
severe weather will be possible. PWAT values approaching 1.5" will
also these storms to be very efficient and flooding can not be ruled
out. Storms will push east across the CWA Tuesday night into
Wednesday morning. Wednesday, the upper level trough will move
through the eastern Plains weakening as it does. An attendant cold
front will move into Wednesday afternoon. Any severe potential is
conditional if the airmass can rebound from morning convection. If
conditions do destabilize severe storms will again be possible
across the eastern 2/3rds of the CWA. The front finally pushes east
of the area Wednesday night and we brief dry out on Wednesday night
and Thursday. Friday night, yet another negatively tilted upper
trough will move into the Plains allowing thunderstorm to overspread
the area. Shear, moisture, and instability will also be conducive
for severe storms Friday night into Saturday. Sunday, the upper
level system moves through the region continuing shower and
thunderstorm chances.
&&
.Aviation...(For the 18Z TAFS through 18Z Monday Afternoon)
Issued at 1210 PM CDT SUN APR 24 2016
VFR conds with sct mid-lvl clouds will persist thru the afternoon
into the evening. Hi-res models as well as the NAM suggest there may
be a few thunderstorms in the VC of the terminals btn 03Z-06Z.
However, thunderstorms will remain north and west of the TAF sites
with the exception of STJ which may experience thunderstorms btn 02Z-
05Z. Otrw...expect sct-bkn cigs around 5kft tonight. Tomorrow morning
models are in good agreement that MVFR cigs btn 1-2kft will move into
the terminals btn 11Z-13Z. Winds this afternoon will remain out of
the south btn 15-20kts with gusts 25-30kts. Winds will diminish
slightly this evening but remain gusty. After midnight gusts will
diminish as winds remain sustained btn 10-15kts out of the SSW.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...73
Aviation...73
[top]
Area Forecast Discussion
National Weather Service Saint Louis MO
331 PM CDT SUN APR 24 2016
.SHORT TERM... (Through Late Tonight)
Issued at 330 PM CDT Sun Apr 24 2016
Most of the convection tonight is expected to remain north of our
forecast area, associated with an upper level low now over southwest
SD and a surface low over central SD which will move eastward
through the northern Plains. Widely scattered, weakening convection
though may move into portions of northeast and central MO as well as
west central IL late tonight as a southwesterly low level jet brings
low level warm air advection and increasing moisture into this area.
Will just have slight chance pops late tonight for areas north and
west of STL. Southerly surface/low level winds, increasing cloud
cover, and relatively high surface dew points will lead to low
temperatures 10 to 15 degrees above normal and warmer than the
previous night.
GKS
.LONG TERM... (Monday through Next Sunday)
Issued at 330 PM CDT Sun Apr 24 2016
Warmer conditions to persist through Tuesday with several weak
shortwaves sliding through helping to trigger scattered showers and
thunderstorms. In the meantime, frontal boundary associated with
main system to slowly sink south, eventually stalling out along I-70
corridor by Tuesday afternoon.
More active weather to ramp up late Tuesday night as low level jet
increases with decent instability and convergence along the stalled
front. Elevated storms, some of which may be severe, could develop
into an MCS and slide east along front. Main threats would be large
hail, damaging winds and possibly a few tornadoes.
Depending on when morning activity diminishes/moves out on
Wednesday, another round of storms to develop as front moves back
north as a warm front and main cold front starts to slide through
Wednesday afternoon/evening. So if atmosphere is able to recharge,
storms to develop ahead of system with main threats being large hail
and damaging winds.
Precipitation to taper off Thursday and Thursday night, before next
chance of rain returns on Friday and persists through Sunday.
Otherwise, the default ridge setup in our part of the CONUS will
ensure that temps remain at or above average throughout the period.
Byrd
&&
.AVIATION... (For the 18z TAFs through 18z Monday Afternoon)
Issued at 1113 AM CDT Sun Apr 24 2016
Just few-scattered diurnal cumulus clouds this afternoon, and
some high level clouds this evening. An upper level low now over
southwest SD and an associated surface low over central SD will
move eastward through the northern Plains tonight and into the
Great Lakes region on Monday. It appears that most of the
convection associated with this storm system will remain north of
the taf sites, although could not rule out a few showers or storms
late tonight and Monday morning impacting UIN and COU. For now
will leave precipitation out of the tafs as the probability is
quite low and the timing still uncertain. Will get some low-mid
level clouds moving into the taf sites late tonight and Monday
morning as a low level jet brings increasing low level moisture
into the area. There may be a brief period of MVFR cigs Monday
morning in UIN or COU. Southerly surface winds, gusty at times
this afternoon and again late Monday morning, will become more
southwesterly Monday morning.
Specifics for KSTL: Few-sct diurnal cumulus clouds this afternoon,
high level clouds tonight, then VFR low-mid level cloudiness on
Monday. There may be a few showers/storms on Monday, mainly during
the afternoon, but will leave the STL taf dry for now as the
probability is quite low and the timing uncertain. Southerly
surface wind will increase to around 13-15 kts this afternoon and
become gusty. The southerly wind will weaken a little this
evening, then become more southwesterly Monday morning as well as
strengthen and become gusty again by late Monday morning.
GKS
&&
.PRELIMINARY POINT TEMPS/POPS...
Saint Louis 61 83 66 83 / 10 20 20 20
Quincy 60 80 61 79 / 20 20 20 20
Columbia 60 80 63 81 / 20 20 20 20
Jefferson City 60 82 64 82 / 20 20 20 20
Salem 59 80 65 81 / 10 20 20 20
Farmington 58 81 64 81 / 10 10 20 20
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
[top]
Area Forecast Discussion
National Weather Service Springfield MO
259 PM CDT SUN APR 24 2016
...Warm and Breezy The Next Couple of Days...Strong to Severe
Storms Possible Tuesday Through Wednesday...
.SHORT TERM...(This evening through Monday)
Issued at 216 PM CDT Sun Apr 24 2016
There are no big changes in the overall forecast. Temperatures
warmed up into the low 80s at some locations today with partly
cloudy skies. A shortwave is currently moving across the northern
Plains this evening. Quiet weather will continue for most of the
area through tonight. All model guidance and high resolution short
term data indicate that scattered convection will develop to our
northwest this evening. This convection will decrease and weaken
as it moves east-northeastward tonight. There will be a slight
chance for an isolated thunderstorms or a few showers to reach the
far western areas like southeast Kansas and west central Missouri
very late tonight. This convection will move into a less favorable
environment as they move eastward tonight.
The area will remain mostly dry...breezy...and warm on Monday.
There may be a weak boundary of weak convergence that will try to
move down into the central Missouri area tomorrow. A few of the
models indicate a couple showers...isolated storm may try to develop
over the northern portion of the Ozarks. This will be very hard
due to a strong cap. There will be more clouds on Monday with
moisture low level moisture increasing.
.LONG TERM...(Monday Night through Sunday)
Issued at 216 PM CDT Sun Apr 24 2016
Models do suggest maybe a slightly better chance for a few showers
and storms to develop late Monday night into Tuesday morning. This
may have be because of low level jet interacting with the boundary
in the area at it lifts northward. Will keep the mention for
scattered showers and a storm or two possible across the central
Missouri area late Monday night.
A strong cap will develop on Tuesday afternoon across much of the
area. We will see instability develop of 3000 to 4000 J/KG MUCape.
A negatively titled trough will begin to move out across the
Central Plains region Tuesday afternoon and evening. We will be
watching the area just west of our local area for the development
of strong to severe convection across Oklahoma and Kansas late
Tuesday afternoon ahead of a dry line. Models indicated that this
severe convection will move into our southeast Kansas counties and
extreme western Missouri late Tuesday evening and overnight. There
are some uncertainties on timing and and location of best
potential for severe weather...but all modes of severe weather
appear possible.
The area of showers and thunderstorms will continue to move
eastward during early Wednesday morning across the Missouri Ozarks
region. The big question for Wednesday is how much are we going to
clear out of the older convection and destabilize again for new
thunderstorms to develop. If we can heat the atmosphere back
up...we can see another round of strong to severe storms to
develop over the area Wednesday afternoon with all modes of severe
weather possible. Storm total rainfall estimates will average
around 1 inch.
The system begins to exit the area Wednesday evening and night as
it moves off to east. Thursday will be a break in between weather
systems with mostly dry and quiet weather expected. Another storm
system will begin to develop to our southwest across Texas and
Oklahoma Thursday night and begin to move into the area Friday.
This will be a slow moving system bringing widespread showers and
storms to the area Friday through Saturday night. Could possibly
see some more strong thunderstorms by the weekend. Additional 1 to
2 inches of rainfall look reasonable for the weekend system.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 1218 PM CDT Sun Apr 24 2016
Breezy south winds will continue today across the area. High
clouds will start to increase tonight, with some MVFR cigs
possible by morning at JLN. LLWS will also be a concern tonight.
Lower clouds will remain in place on Monday, with moderate
southwest winds during the day. Right now it appears as if any
precipitation chances will hold off until Monday night and
Tuesday.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Boxell
Area Forecast Discussion
National Weather Service Springfield MO
1220 PM CDT SUN APR 24 2016
...18Z Aviation Update...
.SHORT TERM...(Today and tonight)
Issued at 343 AM CDT Sun Apr 24 2016
An upper level ridge remains over the central U.S. early this
morning along with a warm air mass. Early morning temperatures are
currently in the upper 50s to lower 60s. Temperatures will not
drop much more early this morning with lows in the middle 50s to
around 60 occurring.
An upper level low is currently over Wyoming early this morning,
and will track to the east and opening up today into tonight. This
will start to push the ridge to the east today. Surface low
pressure has developed ahead of the upper level low across the
plains. The pressure gradient will tighten across the region today
as the low tracks east. Temperatures will be very similar to those
that were observed on Saturday with highs in the upper 70s to the
lower 80s. There will be few more clouds today than yesterday but
still plenty of sunshine will occur. Southerly winds will increase
and be gusty today ahead of the approaching system and gusts over
30 mph will occur at times mainly along and west of Hwy 65 this
afternoon.
A cold front associated with the surface low will track east
across portions of central and eastern Nebraska and Kansas today
into tonight. This evening Thunderstorms will develop along the
front to the west and northwest of the forecast area. The front
will remain to the west and north of the area and not move into
the area overnight. Storms will likely move off the front but
instability will be weaker the farther to the east and with the
better lift remaining west of the area storms will weaken as they
push into the area. A few storms may make it into the area before
dissipating but most locations should remain dry.
.LONG TERM...(Monday through Saturday)
Issued at 343 AM CDT Sun Apr 24 2016
The front is expected to remain north of the area on Monday as the
upper level trough and surface low push off to the east. Shortwave
upper level ridging will build over the area on Monday. Can not
rule out an isolated shower/rumble of thunder mainly in the
morning hours as isentropic lift spreads across the area ahead of
the ridge, but expect most location to remain dry during the day
on Monday.
Isentropic lift will again develop, mainly over the extreme
southeastern Kansas and far southwestern Missouri Monday night
into Tuesday morning. Instability will start to develop across
the area as Gulf moisture spread north, but a cap will also develop
across the area. The cap does weaken some for an elevated storm,
but it does not go completely away. Did include a chance for
thunderstorms to develop across the western portions of the
forecast area to account for this. Instability for an elevated
storm will be limited so not expecting strong to severe storms at
this time.
An upper level trough will lift across the plains on Tuesday then
to the north of the area on Wednesday. Instability will increase
across the region ahead of this system but so will the cap. So,
besides a few morning storms mentioned above, think the cap will
keep much of the afternoon hours dry. Surface low pressure will
develop across the central Plains and connect with the front that
will stall to the north of the area, with it being a warm front.
As the Low level jet increases Tuesday evening storms are expected
to develop along and just north of the warm front, at this time
the front is expected to remain north of the area and these storms
should too.
As the low lifts to the northeast a cold front will move east
across central Kansas and central Oklahoma late Tuesday afternoon
into Tuesday evening. The cap will weaken enough for storms to
develop along and ahead of the front. They should be able to move
off the front as the front only slowly moves east, resulting in
the potential for supercells. The front will not push east into
the area Tuesday night, but cold pools from the storms could
congeal and keep the storms going to the east, in more of a line
or line segments, pushing into and across the area Tuesday night
into Wednesday morning. Instability will be weaker given the
overnight timing, but will remain strong enough to support a
severe risk across the area Tuesday night and Wednesday. Low level
shear will increase with the approach of the storm system, so all
modes of severe weather will be possible, through large hail and
damaging straight line winds will be the main risk. The front will
push across the region Wednesday with the storms/rain chances
ending Wednesday evening.
Thursday will be a dry day then yet another storm system will
track into and across the region Friday into the weekend bringing
additional rounds for showers and thunderstorms to the region.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 1218 PM CDT Sun Apr 24 2016
Breezy south winds will continue today across the area. High
clouds will start to increase tonight, with some MVFR cigs
possible by morning at JLN. LLWS will also be a concern tonight.
Lower clouds will remain in place on Monday, with moderate
southwest winds during the day. Right now it appears as if any
precipitation chances will hold off until Monday night and
Tuesday.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...Boxell
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1210 PM CDT SUN APR 24 2016
.Discussion...
Issued at 417 AM CDT SUN APR 24 2016
Today - Tonight:
The first in a series of upper level systems will bring scattered
convection to at least the northwest half of the CWA starting late
this afternoon. A closed upper low now over WY is progged to track
east and reach the central SD/NE border by late afternoon. A
nocturnal low-level jet over the Central Plains and modest
isentropic ascent are currently aiding a narrow band of elevated
convection from central KS into south central NE. This activity is
expected to lift northeast and possibly graze the northwest tip of
MO this morning before dissipating.
Several additional features will generate strong/severe convection
from western OK through central KS and into far northwest MO. A
dryline will set up from central KS through far western OK this
afternoon while a cold front swings southeast from under the WY
system. As a h7 vorticity max/lobe emerges from under the WY system
and ejects northeast across KS scattered surface-based convection
will form along the KS/OK portion of the dryline. In addition storms
will form over southeast NE/northeast KS where a weak boundary left
by this mornings convection or a pre-frontal convergence zone lies.
The NE/KS convection should affect the northwest 1/3 of the CWA late
this afternoon and early evening. Moderate instability around 1500
J/kg with 30kt 0-6km shear may be sufficient to support a few
marginally severe storms. The primary threat will be large hail. The
severe threat will last several hours ending a few hours after
sunset as the storms weaken as they move east into a less favorable
environment. Coverage and intensity will gradually decrease with
time such that most of the convection will have dissipated by the
pre-dawn hours of Monday morning.
The severe storms which form along the KS/OK dryline may never reach
the CWA as they will weaken and tend to decrease in coverage as they
lift northeast and off the dryline. Accept the model trends in
slowing the arrival of the convection into the CWA as well as
decreasing it in coverage. So, have lowered PoPs for all but the
northwest 1/3 of the CWA as well as limit the QPF.
Monday - Saturday:
As noted in yesterday`s discussion this will be a very active period
with several additional periods of strong/possibly severe convection
as well as the potential for heavy rainfall Tuesday night/Wednesday.
While Monday looks relatively quiet isolated convection is still
possible as the earlier mentioned cold front stalls over the CWA and
around 1000 J/kg of instability will be available. Increasing mid
level heights and the lack of an upper level feature should greatly
limit convection.
By Tuesday the next closed upper system will move out of the Central
High Plains. This system will be much larger with a better defined
negatively tilted shortwave ejecting northeast across KS. With
surface dewpoints likely well into the 60s advecting into the region
there will be ample instability, in excess of 2500 J/kg, to supply
the needed energy for severe convection Tuesday evening. Will need
to keep a close eye on where the warm front will be as it will be a
primary focus for severe storm development. However, the shear will
be near the lower end of the threshold with 0-6km shear in the 25-
30kt range. Heavy rainfall will also be a concern Tuesday
night/Wednesday as precipitable water values between 1.25 and 1.5
inches are near the 99% percentile.
Should see at least a one day break in the rain on Thursday,
possibly carrying over into the first part of Friday before the next
upper trough sends the first wave of warm air advection convection
into the CWA by Friday evening. Timing differences between the ECMWF
and the GFS by the end of the week requires more of a broadbrush
approach on rain chances. Even then PoPs will be rather high this
far out. Should we get as much rain as the models are advertising in
the upcoming week we should eliminate the yearly shortage in
precipitation.
&&
.Aviation...(For the 18Z TAFS through 18Z Monday Afternoon)
Issued at 1210 PM CDT SUN APR 24 2016
VFR conds with sct mid-lvl clouds will persist thru the afternoon
into the evening. Hi-res models as well as the NAM suggest there may
be a few thunderstorms in the VC of the terminals btn 03Z-06Z.
However, thunderstorms will remain north and west of the TAF sites
with the exception of STJ which may experience thunderstorms btn 02Z-
05Z. Otrw...expect sct-bkn cigs around 5kft tonight. Tomorrow morning
models are in good agreement that MVFR cigs btn 1-2kft will move into
the terminals btn 11Z-13Z. Winds this afternoon will remain out of
the south btn 15-20kts with gusts 25-30kts. Winds will diminish
slightly this evening but remain gusty. After midnight gusts will
diminish as winds remain sustained btn 10-15kts out of the SSW.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...MJ
Aviation...73
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1210 PM CDT SUN APR 24 2016
.Discussion...
Issued at 417 AM CDT SUN APR 24 2016
Today - Tonight:
The first in a series of upper level systems will bring scattered
convection to at least the northwest half of the CWA starting late
this afternoon. A closed upper low now over WY is progged to track
east and reach the central SD/NE border by late afternoon. A
nocturnal low-level jet over the Central Plains and modest
isentropic ascent are currently aiding a narrow band of elevated
convection from central KS into south central NE. This activity is
expected to lift northeast and possibly graze the northwest tip of
MO this morning before dissipating.
Several additional features will generate strong/severe convection
from western OK through central KS and into far northwest MO. A
dryline will set up from central KS through far western OK this
afternoon while a cold front swings southeast from under the WY
system. As a h7 vorticity max/lobe emerges from under the WY system
and ejects northeast across KS scattered surface-based convection
will form along the KS/OK portion of the dryline. In addition storms
will form over southeast NE/northeast KS where a weak boundary left
by this mornings convection or a pre-frontal convergence zone lies.
The NE/KS convection should affect the northwest 1/3 of the CWA late
this afternoon and early evening. Moderate instability around 1500
J/kg with 30kt 0-6km shear may be sufficient to support a few
marginally severe storms. The primary threat will be large hail. The
severe threat will last several hours ending a few hours after
sunset as the storms weaken as they move east into a less favorable
environment. Coverage and intensity will gradually decrease with
time such that most of the convection will have dissipated by the
pre-dawn hours of Monday morning.
The severe storms which form along the KS/OK dryline may never reach
the CWA as they will weaken and tend to decrease in coverage as they
lift northeast and off the dryline. Accept the model trends in
slowing the arrival of the convection into the CWA as well as
decreasing it in coverage. So, have lowered PoPs for all but the
northwest 1/3 of the CWA as well as limit the QPF.
Monday - Saturday:
As noted in yesterday`s discussion this will be a very active period
with several additional periods of strong/possibly severe convection
as well as the potential for heavy rainfall Tuesday night/Wednesday.
While Monday looks relatively quiet isolated convection is still
possible as the earlier mentioned cold front stalls over the CWA and
around 1000 J/kg of instability will be available. Increasing mid
level heights and the lack of an upper level feature should greatly
limit convection.
By Tuesday the next closed upper system will move out of the Central
High Plains. This system will be much larger with a better defined
negatively tilted shortwave ejecting northeast across KS. With
surface dewpoints likely well into the 60s advecting into the region
there will be ample instability, in excess of 2500 J/kg, to supply
the needed energy for severe convection Tuesday evening. Will need
to keep a close eye on where the warm front will be as it will be a
primary focus for severe storm development. However, the shear will
be near the lower end of the threshold with 0-6km shear in the 25-
30kt range. Heavy rainfall will also be a concern Tuesday
night/Wednesday as precipitable water values between 1.25 and 1.5
inches are near the 99% percentile.
Should see at least a one day break in the rain on Thursday,
possibly carrying over into the first part of Friday before the next
upper trough sends the first wave of warm air advection convection
into the CWA by Friday evening. Timing differences between the ECMWF
and the GFS by the end of the week requires more of a broadbrush
approach on rain chances. Even then PoPs will be rather high this
far out. Should we get as much rain as the models are advertising in
the upcoming week we should eliminate the yearly shortage in
precipitation.
&&
.Aviation...(For the 18Z TAFS through 18Z Monday Afternoon)
Issued at 1210 PM CDT SUN APR 24 2016
VFR conds with sct mid-lvl clouds will persist thru the afternoon
into the evening. Hi-res models as well as the NAM suggest there may
be a few thunderstorms in the VC of the terminals btn 03Z-06Z.
However, thunderstorms will remain north and west of the TAF sites
with the exception of STJ which may experience thunderstorms btn 02Z-
05Z. Otrw...expect sct-bkn cigs around 5kft tonight. Tomorrow morning
models are in good agreement that MVFR cigs btn 1-2kft will move into
the terminals btn 11Z-13Z. Winds this afternoon will remain out of
the south btn 15-20kts with gusts 25-30kts. Winds will diminish
slightly this evening but remain gusty. After midnight gusts will
diminish as winds remain sustained btn 10-15kts out of the SSW.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...MJ
Aviation...73
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1150 AM CDT SUN APR 24 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 355 AM CDT Sun Apr 24 2016
The sfc ridge is expected to build further ewd today, allowing sly
winds across the region. An upper ridge is expected to remain in
place today, which will keep precip W of the CWA.
The light FG across ern portions of the CWA shud dissipate by mid-
morning. This area shud also see the most cloud cover, but is still
expected to be only sct coverage. However, high clouds shud cover
the region. Believe these clouds, other than those lower over ern
CWA, will have little impact on temps today. Have trended aoa the
warmer guidance across the region.
Tilly
.LONG TERM... (Tonight through Saturday)
Issued at 355 AM CDT Sun Apr 24 2016
An omega block will dominate Canada and the northern CONUS thru this
week, with upper longwave TROFs on the west and east coasts and the
RIDGE component over the Plains. A series of strong Pacific storms
will run just south of this blocking pattern, being dropped off from
the west coast TROF and being picked up by the east coast TROF a few
days later, with an overall track to the E-NE thru our region. Model
progs show that each successive storm system will track a bit
further south than its predecessor.
The first storm system will track to our north late tonight and into
Monday, and will be just a glancing blow to our region as a result,
with what forms mostly upstream initially to our northwest working
its way in late tonight as it weakens with a possible low level
boundary setting up for additional development further southeast
during the day on Monday.
In the wake of this first storm system, a cold front will drop down
late Monday night into Tuesday and will maintain a low chance for
rain. Severe storm chances up until this point look to be low.
The second Pacific storm system will be more of a direct hit as it
will initially correspond well with the surface frontal boundary
buckling north as a warm front late Tuesday night into Wednesday
morning. This should result in elevated storms, with hail as their
primary severe threat during that time.
Heading into Wednesday afternoon and evening, it will depend heavily
on how far north the front gets. Models continue to skiddishly
track the frontal boundary a tad further south than where they were
progging it 24hrs prior, but the bottom line still remains nearly
the same for now, with a strong shear and unstable environment with
a low level boundary for severe storm formation potential, including
tornadoes.
Things dry out briefly for late in the work week before the third
storm system approaches from the west for the upcoming weekend and
rain chances ramp up again. But with this storm system expected to
track the furthest south, this next episode of rain could very well
be mostly showers with imbedded storms if this track holds, with any
severe potential remaining well to the south.
Otherwise, the default RIDGE setup in our part of the CONUS will
ensure that temps remain at or above average throughout the period.
TES
&&
.AVIATION... (For the 18z TAFs through 18z Monday Afternoon)
Issued at 1113 AM CDT Sun Apr 24 2016
Just few-scattered diurnal cumulus clouds this afternoon, and
some high level clouds this evening. An upper level low now over
southwest SD and an associated surface low over central SD will
move eastward through the northern Plains tonight and into the
Great Lakes region on Monday. It appears that most of the
convection associated with this storm system will remain north of
the taf sites, although could not rule out a few showers or storms
late tonight and Monday morning impacting UIN and COU. For now
will leave precipitation out of the tafs as the probability is
quite low and the timing still uncertain. Will get some low-mid
level clouds moving into the taf sites late tonight and Monday
morning as a low level jet brings increasing low level moisture
into the area. There may be a brief period of MVFR cigs Monday
morning in UIN or COU. Southerly surface winds, gusty at times
this afternoon and again late Monday morning, will become more
southwesterly Monday morning.
Specifics for KSTL: Few-sct diurnal cumulus clouds this afternoon,
high level clouds tonight, then VFR low-mid level cloudiness on
Monday. There may be a few showers/storms on Monday, mainly during
the afternoon, but will leave the STL taf dry for now as the
probability is quite low and the timing uncertain. Southerly
surface wind will increase to around 13-15 kts this afternoon and
become gusty. The southerly wind will weaken a little this
evening, then become more southwesterly Monday morning as well as
strengthen and become gusty again by late Monday morning.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
654 AM CDT SUN APR 24 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 355 AM CDT Sun Apr 24 2016
The sfc ridge is expected to build further ewd today, allowing sly
winds across the region. An upper ridge is expected to remain in
place today, which will keep precip W of the CWA.
The light FG across ern portions of the CWA shud dissipate by mid-
morning. This area shud also see the most cloud cover, but is still
expected to be only sct coverage. However, high clouds shud cover
the region. Believe these clouds, other than those lower over ern
CWA, will have little impact on temps today. Have trended aoa the
warmer guidance across the region.
Tilly
.LONG TERM... (Tonight through Saturday)
Issued at 355 AM CDT Sun Apr 24 2016
An omega block will dominate Canada and the northern CONUS thru this
week, with upper longwave TROFs on the west and east coasts and the
RIDGE component over the Plains. A series of strong Pacific storms
will run just south of this blocking pattern, being dropped off from
the west coast TROF and being picked up by the east coast TROF a few
days later, with an overall track to the E-NE thru our region. Model
progs show that each successive storm system will track a bit
further south than its predecessor.
The first storm system will track to our north late tonight and into
Monday, and will be just a glancing blow to our region as a result,
with what forms mostly upstream initially to our northwest working
its way in late tonight as it weakens with a possible low level
boundary setting up for additional development further southeast
during the day on Monday.
In the wake of this first storm system, a cold front will drop down
late Monday night into Tuesday and will maintain a low chance for
rain. Severe storm chances up until this point look to be low.
The second Pacific storm system will be more of a direct hit as it
will initially correspond well with the surface frontal boundary
buckling north as a warm front late Tuesday night into Wednesday
morning. This should result in elevated storms, with hail as their
primary severe threat during that time.
Heading into Wednesday afternoon and evening, it will depend heavily
on how far north the front gets. Models continue to skiddishly
track the frontal boundary a tad further south than where they were
progging it 24hrs prior, but the bottom line still remains nearly
the same for now, with a strong shear and unstable environment with
a low level boundary for severe storm formation potential, including
tornadoes.
Things dry out briefly for late in the work week before the third
storm system approaches from the west for the upcoming weekend and
rain chances ramp up again. But with this storm system expected to
track the furthest south, this next episode of rain could very well
be mostly showers with imbedded storms if this track holds, with any
severe potential remaining well to the south.
Otherwise, the default RIDGE setup in our part of the CONUS will
ensure that temps remain at or above average throughout the period.
TES
&&
.AVIATION... (For the 12z TAFs through 12z Monday Morning)
Issued at 640 AM CDT Sun Apr 24 2016
Winds will become sly and increase this morning with gusts to
around 20 kts possible, mainly at UIN/COU. Isod to sct TSRA are
possible late tonight, possibly impacting UIN/COU. Given the isod
nature of these storms, have held off mentioning in the TAF attm.
A bkn cloud deck will also move into the region late tonight, but
is expected to remain VFR.
Specifics for KSTL: Once current FG dissipates, VFR and dry
conditions expected thru the TAF period.
Tilly
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
654 AM CDT SUN APR 24 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 355 AM CDT Sun Apr 24 2016
The sfc ridge is expected to build further ewd today, allowing sly
winds across the region. An upper ridge is expected to remain in
place today, which will keep precip W of the CWA.
The light FG across ern portions of the CWA shud dissipate by mid-
morning. This area shud also see the most cloud cover, but is still
expected to be only sct coverage. However, high clouds shud cover
the region. Believe these clouds, other than those lower over ern
CWA, will have little impact on temps today. Have trended aoa the
warmer guidance across the region.
Tilly
.LONG TERM... (Tonight through Saturday)
Issued at 355 AM CDT Sun Apr 24 2016
An omega block will dominate Canada and the northern CONUS thru this
week, with upper longwave TROFs on the west and east coasts and the
RIDGE component over the Plains. A series of strong Pacific storms
will run just south of this blocking pattern, being dropped off from
the west coast TROF and being picked up by the east coast TROF a few
days later, with an overall track to the E-NE thru our region. Model
progs show that each successive storm system will track a bit
further south than its predecessor.
The first storm system will track to our north late tonight and into
Monday, and will be just a glancing blow to our region as a result,
with what forms mostly upstream initially to our northwest working
its way in late tonight as it weakens with a possible low level
boundary setting up for additional development further southeast
during the day on Monday.
In the wake of this first storm system, a cold front will drop down
late Monday night into Tuesday and will maintain a low chance for
rain. Severe storm chances up until this point look to be low.
The second Pacific storm system will be more of a direct hit as it
will initially correspond well with the surface frontal boundary
buckling north as a warm front late Tuesday night into Wednesday
morning. This should result in elevated storms, with hail as their
primary severe threat during that time.
Heading into Wednesday afternoon and evening, it will depend heavily
on how far north the front gets. Models continue to skiddishly
track the frontal boundary a tad further south than where they were
progging it 24hrs prior, but the bottom line still remains nearly
the same for now, with a strong shear and unstable environment with
a low level boundary for severe storm formation potential, including
tornadoes.
Things dry out briefly for late in the work week before the third
storm system approaches from the west for the upcoming weekend and
rain chances ramp up again. But with this storm system expected to
track the furthest south, this next episode of rain could very well
be mostly showers with imbedded storms if this track holds, with any
severe potential remaining well to the south.
Otherwise, the default RIDGE setup in our part of the CONUS will
ensure that temps remain at or above average throughout the period.
TES
&&
.AVIATION... (For the 12z TAFs through 12z Monday Morning)
Issued at 640 AM CDT Sun Apr 24 2016
Winds will become sly and increase this morning with gusts to
around 20 kts possible, mainly at UIN/COU. Isod to sct TSRA are
possible late tonight, possibly impacting UIN/COU. Given the isod
nature of these storms, have held off mentioning in the TAF attm.
A bkn cloud deck will also move into the region late tonight, but
is expected to remain VFR.
Specifics for KSTL: Once current FG dissipates, VFR and dry
conditions expected thru the TAF period.
Tilly
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
638 AM CDT SUN APR 24 2016
.Discussion...
Issued at 417 AM CDT SUN APR 24 2016
Today - Tonight:
The first in a series of upper level systems will bring scattered
convection to at least the northwest half of the CWA starting late
this afternoon. A closed upper low now over WY is progged to track
east and reach the central SD/NE border by late afternoon. A
nocturnal low-level jet over the Central Plains and modest
isentropic ascent are currently aiding a narrow band of elevated
convection from central KS into south central NE. This activity is
expected to lift northeast and possibly graze the northwest tip of
MO this morning before dissipating.
Several additional features will generate strong/severe convection
from western OK through central KS and into far northwest MO. A
dryline will set up from central KS through far western OK this
afternoon while a cold front swings southeast from under the WY
system. As a h7 vorticity max/lobe emerges from under the WY system
and ejects northeast across KS scattered surface-based convection
will form along the KS/OK portion of the dryline. In addition storms
will form over southeast NE/northeast KS where a weak boundary left
by this mornings convection or a pre-frontal convergence zone lies.
The NE/KS convection should affect the northwest 1/3 of the CWA late
this afternoon and early evening. Moderate instability around 1500
J/kg with 30kt 0-6km shear may be sufficient to support a few
marginally severe storms. The primary threat will be large hail. The
severe threat will last several hours ending a few hours after
sunset as the storms weaken as they move east into a less favorable
environment. Coverage and intensity will gradually decrease with
time such that most of the convection will have dissipated by the
pre-dawn hours of Monday morning.
The severe storms which form along the KS/OK dryline may never reach
the CWA as they will weaken and tend to decrease in coverage as they
lift northeast and off the dryline. Accept the model trends in
slowing the arrival of the convection into the CWA as well as
decreasing it in coverage. So, have lowered PoPs for all but the
northwest 1/3 of the CWA as well as limit the QPF.
Monday - Saturday:
As noted in yesterday`s discussion this will be a very active period
with several additional periods of strong/possibly severe convection
as well as the potential for heavy rainfall Tuesday night/Wednesday.
While Monday looks relatively quiet isolated convection is still
possible as the earlier mentioned cold front stalls over the CWA and
around 1000 J/kg of instability will be available. Increasing mid
level heights and the lack of an upper level feature should greatly
limit convection.
By Tuesday the next closed upper system will move out of the Central
High Plains. This system will be much larger with a better defined
negatively tilted shortwave ejecting northeast across KS. With
surface dewpoints likely well into the 60s advecting into the region
there will be ample instability, in excess of 2500 J/kg, to supply
the needed energy for severe convection Tuesday evening. Will need
to keep a close eye on where the warm front will be as it will be a
primary focus for severe storm development. However, the shear will
be near the lower end of the threshold with 0-6km shear in the 25-
30kt range. Heavy rainfall will also be a concern Tuesday
night/Wednesday as precipitable water values between 1.25 and 1.5
inches are near the 99% percentile.
Should see at least a one day break in the rain on Thursday,
possibly carrying over into the first part of Friday before the next
upper trough sends the first wave of warm air advection convection
into the CWA by Friday evening. Timing differences between the ECMWF
and the GFS by the end of the week requires more of a broadbrush
approach on rain chances. Even then PoPs will be rather high this
far out. Should we get as much rain as the models are advertising in
the upcoming week we should eliminate the yearly shortage in
precipitation.
&&
.Aviation...(For the 12Z TAFS through 12Z Monday Morning)
Issued at 632 AM CDT SUN APR 24 2016
Scattered elevated showers will cross far northwest MO through 14z
before lifting into IA. Otherwise VFR conditions with strong and
gusty southerly winds developing by mid morning and lasting well into
the evening hours.
Expect to see scattered convection to reform over southeast
NE/northeast KS by late afternoon and track across northwest MO. A
few strong/marginally severe storms possible over this area towards
sunset and lasting into mid evening. Other scattered convection is
possible over east central KS and west central MO after 00z but with
the activity weakening quickly by mid evening. Most of the convection
will decrease greatly in coverage and intensity after midnight as it
heads towards northeast MO.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...MJ
Aviation...MJ
Area Forecast Discussion
National Weather Service Springfield MO
607 AM CDT SUN APR 24 2016
.SHORT TERM...(Today and tonight)
Issued at 343 AM CDT Sun Apr 24 2016
An upper level ridge remains over the central U.S. early this
morning along with a warm air mass. Early morning temperatures are
currently in the upper 50s to lower 60s. Temperatures will not
drop much more early this morning with lows in the middle 50s to
around 60 occurring.
An upper level low is currently over Wyoming early this morning,
and will track to the east and opening up today into tonight. This
will start to push the ridge to the east today. Surface low
pressure has developed ahead of the upper level low across the
plains. The pressure gradient will tighten across the region today
as the low tracks east. Temperatures will be very similar to those
that were observed on Saturday with highs in the upper 70s to the
lower 80s. There will be few more clouds today than yesterday but
still plenty of sunshine will occur. Southerly winds will increase
and be gusty today ahead of the approaching system and gusts over
30 mph will occur at times mainly along and west of Hwy 65 this
afternoon.
A cold front associated with the surface low will track east
across portions of central and eastern Nebraska and Kansas today
into tonight. This evening Thunderstorms will develop along the
front to the west and northwest of the forecast area. The front
will remain to the west and north of the area and not move into
the area overnight. Storms will likely move off the front but
instability will be weaker the farther to the east and with the
better lift remaining west of the area storms will weaken as they
push into the area. A few storms may make it into the area before
dissipating but most locations should remain dry.
.LONG TERM...(Monday through Saturday)
Issued at 343 AM CDT Sun Apr 24 2016
The front is expected to remain north of the area on Monday as the
upper level trough and surface low push off to the east. Shortwave
upper level ridging will build over the area on Monday. Can not
rule out an isolated shower/rumble of thunder mainly in the
morning hours as isentropic lift spreads across the area ahead of
the ridge, but expect most location to remain dry during the day
on Monday.
Isentropic lift will again develop, mainly over the extreme
southeastern Kansas and far southwestern Missouri Monday night
into Tuesday morning. Instability will start to develop across
the area as Gulf moisture spread north, but a cap will also develop
across the area. The cap does weaken some for an elevated storm,
but it does not go completely away. Did include a chance for
thunderstorms to develop across the western portions of the
forecast area to account for this. Instability for an elevated
storm will be limited so not expecting strong to severe storms at
this time.
An upper level trough will lift across the plains on Tuesday then
to the north of the area on Wednesday. Instability will increase
across the region ahead of this system but so will the cap. So,
besides a few morning storms mentioned above, think the cap will
keep much of the afternoon hours dry. Surface low pressure will
develop across the central Plains and connect with the front that
will stall to the north of the area, with it being a warm front.
As the Low level jet increases Tuesday evening storms are expected
to develop along and just north of the warm front, at this time
the front is expected to remain north of the area and these storms
should too.
As the low lifts to the northeast a cold front will move east
across central Kansas and central Oklahoma late Tuesday afternoon
into Tuesday evening. The cap will weaken enough for storms to
develop along and ahead of the front. They should be able to move
off the front as the front only slowly moves east, resulting in
the potential for supercells. The front will not push east into
the area Tuesday night, but cold pools from the storms could
congeal and keep the storms going to the east, in more of a line
or line segments, pushing into and across the area Tuesday night
into Wednesday morning. Instability will be weaker given the
overnight timing, but will remain strong enough to support a
severe risk across the area Tuesday night and Wednesday. Low level
shear will increase with the approach of the storm system, so all
modes of severe weather will be possible, through large hail and
damaging straight line winds will be the main risk. The front will
push across the region Wednesday with the storms/rain chances
ending Wednesday evening.
Thursday will be a dry day then yet another storm system will
track into and across the region Friday into the weekend bringing
additional rounds for showers and thunderstorms to the region.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
Issued at 558 AM CDT Sun Apr 24 2016
Breezy conditions are expected from late morning through the
afternoon as the pressure gradient increases over the region ahead
of an area of low pressure. Will see wind gusts today at JLN/SGF
at around 25 to 28 kts at times. Still expecting only VFR ceilings
at this time through the terminal forecast.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...Lindenberg
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
417 AM CDT SUN APR 24 2016
.Discussion...
Issued at 417 AM CDT SUN APR 24 2016
Today - Tonight:
The first in a series of upper level systems will bring scattered
convection to at least the northwest half of the CWA starting late
this afternoon. A closed upper low now over WY is progged to track
east and reach the central SD/NE border by late afternoon. A
nocturnal low-level jet over the Central Plains and modest
isentropic ascent are currently aiding a narrow band of elevated
convection from central KS into south central NE. This activity is
expected to lift northeast and possibly graze the northwest tip of
MO this morning before dissipating.
Several additional features will generate strong/severe convection
from western OK through central KS and into far northwest MO. A
dryline will set up from central KS through far western OK this
afternoon while a cold front swings southeast from under the WY
system. As a h7 vorticity max/lobe emerges from under the WY system
and ejects northeast across KS scattered surface-based convection
will form along the KS/OK portion of the dryline. In addition storms
will form over southeast NE/northeast KS where a weak boundary left
by this mornings convection or a pre-frontal convergence zone lies.
The NE/KS convection should affect the northwest 1/3 of the CWA late
this afternoon and early evening. Moderate instability around 1500
J/kg with 30kt 0-6km shear may be sufficient to support a few
marginally severe storms. The primary threat will be large hail. The
severe threat will last several hours ending a few hours after
sunset as the storms weaken as they move east into a less favorable
environment. Coverage and intensity will gradually decrease with
time such that most of the convection will have dissipated by the
pre-dawn hours of Monday morning.
The severe storms which form along the KS/OK dryline may never reach
the CWA as they will weaken and tend to decrease in coverage as they
lift northeast and off the dryline. Accept the model trends in
slowing the arrival of the convection into the CWA as well as
decreasing it in coverage. So, have lowered PoPs for all but the
northwest 1/3 of the CWA as well as limit the QPF.
Monday - Saturday:
As noted in yesterday`s discussion this will be a very active period
with several additional periods of strong/possibly severe convection
as well as the potential for heavy rainfall Tuesday night/Wednesday.
While Monday looks relatively quiet isolated convection is still
possible as the earlier mentioned cold front stalls over the CWA and
around 1000 J/kg of instability will be available. Increasing mid
level heights and the lack of an upper level feature should greatly
limit convection.
By Tuesday the next closed upper system will move out of the Central
High Plains. This system will be much larger with a better defined
negatively tilted shortwave ejecting northeast across KS. With
surface dewpoints likely well into the 60s advecting into the region
there will be ample instability, in excess of 2500 J/kg, to supply
the needed energy for severe convection Tuesday evening. Will need
to keep a close eye on where the warm front will be as it will be a
primary focus for severe storm development. However, the shear will
be near the lower end of the threshold with 0-6km shear in the 25-
30kt range. Heavy rainfall will also be a concern Tuesday
night/Wednesday as precipitable water values between 1.25 and 1.5
inches are near the 99% percentile.
Should see at least a one day break in the rain on Thursday,
possibly carrying over into the first part of Friday before the next
upper trough sends the first wave of warm air advection convection
into the CWA by Friday evening. Timing differences between the ECMWF
and the GFS by the end of the week requires more of a broadbrush
approach on rain chances. Even then PoPs will be rather high this
far out. Should we get as much rain as the models are advertising in
the upcoming week we should eliminate the yearly shortage in
precipitation.
&&
.Aviation...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1046 PM CDT SAT APR 23 2016
VFR conditions expected through much of the fcst period. Latest
model runs suggesting the bulk of thunderstorm activity will remain
west of the forecast area. Cannot rule out some isolated convection
holding itself together as it moves east off the dryline in central
Kansas...but activity will be moving into a more and more unfavorable
environment with further eastward progress. In any event...have
inserted a VCTS mention for STJ...and later updates can address the
KC terminals if trends begin to change. The other main concern
remains the likelihood for LLWS early this morning thanks to a strong
southwesterly low-level jet...and have maintained mention for all
terminals with the 06z package. Meanwhile...southerly winds of 10-15
kts overnight will increase after 16z on Sunday with gusts up to 30
kts possible during the afternoon hours.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...MJ
Aviation...32
Area Forecast Discussion
National Weather Service Saint Louis MO
355 AM CDT SUN APR 24 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 355 AM CDT Sun Apr 24 2016
The sfc ridge is expected to build further ewd today, allowing sly
winds across the region. An upper ridge is expected to remain in
place today, which will keep precip W of the CWA.
The light FG across ern portions of the CWA shud dissipate by mid-
morning. This area shud also see the most cloud cover, but is still
expected to be only sct coverage. However, high clouds shud cover
the region. Believe these clouds, other than those lower over ern
CWA, will have little impact on temps today. Have trended aoa the
warmer guidance across the region.
Tilly
.LONG TERM... (Tonight through Saturday)
Issued at 355 AM CDT Sun Apr 24 2016
An omega block will dominate Canada and the northern CONUS thru this
week, with upper longwave TROFs on the west and east coasts and the
RIDGE component over the Plains. A series of strong Pacific storms
will run just south of this blocking pattern, being dropped off from
the west coast TROF and being picked up by the east coast TROF a few
days later, with an overall track to the E-NE thru our region. Model
progs show that each successive storm system will track a bit
further south than its predecessor.
The first storm system will track to our north late tonight and into
Monday, and will be just a glancing blow to our region as a result,
with what forms mostly upstream initially to our northwest working
its way in late tonight as it weakens with a possible low level
boundary setting up for additional development further southeast
during the day on Monday.
In the wake of this first storm system, a cold front will drop down
late Monday night into Tuesday and will maintain a low chance for
rain. Severe storm chances up until this point look to be low.
The second Pacific storm system will be more of a direct hit as it
will initially correspond well with the surface frontal boundary
buckling north as a warm front late Tuesday night into Wednesday
morning. This should result in elevated storms, with hail as their
primary severe threat during that time.
Heading into Wednesday afternoon and evening, it will depend heavily
on how far north the front gets. Models continue to skiddishly
track the frontal boundary a tad further south than where they were
progging it 24hrs prior, but the bottom line still remains nearly
the same for now, with a strong shear and unstable environment with
a low level boundary for severe storm formation potential, including
tornadoes.
Things dry out briefly for late in the work week before the third
storm system approaches from the west for the upcoming weekend and
rain chances ramp up again. But with this storm system expected to
track the furthest south, this next episode of rain could very well
be mostly showers with imbedded storms if this track holds, with any
severe potential remaining well to the south.
Otherwise, the default RIDGE setup in our part of the CONUS will
ensure that temps remain at or above average throughout the period.
TES
&&
.AVIATION... (For the 06z TAFs through 06z Sunday Night)
Issued at 1152 PM CDT Sat Apr 23 2016
Dry and VFR conditions are still expected at the terminals through
the TAF period. There may be some patchy fog late tonight and
early Sunday over southern Illinois and southeast Missouri. Low
level wind shear is still possible at KUIN and KCOU between 09-15Z
as a 35-40kt low level jet sets up between 1000-2000 feet. Still
expect gusts over 20kts during the late morning and afternoon
hours that will decrease slightly after sunset.
Specifics for KSTL:
Dry and VFR conditions are expected through the TAF period. Gusts
above 20 kts are possible after 18Z on Sunday afternoon.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Springfield MO
347 AM CDT SUN APR 24 2016
.SHORT TERM...(Today and tonight)
Issued at 343 AM CDT Sun Apr 24 2016
An upper level ridge remains over the central U.S. early this
morning along with a warm air mass. Early morning temperatures are
currently in the upper 50s to lower 60s. Temperatures will not
drop much more early this morning with lows in the middle 50s to
around 60 occurring.
An upper level low is currently over Wyoming early this morning,
and will track to the east and opening up today into tonight. This
will start to push the ridge to the east today. Surface low
pressure has developed ahead of the upper level low across the
plains. The pressure gradient will tighten across the region today
as the low tracks east. Temperatures will be very similar to those
that were observed on Saturday with highs in the upper 70s to the
lower 80s. There will be few more clouds today than yesterday but
still plenty of sunshine will occur. Southerly winds will increase
and be gusty today ahead of the approaching system and gusts over
30 mph will occur at times mainly along and west of Hwy 65 this
afternoon.
A cold front associated with the surface low will track east
across portions of central and eastern Nebraska and Kansas today
into tonight. This evening Thunderstorms will develop along the
front to the west and northwest of the forecast area. The front
will remain to the west and north of the area and not move into
the area overnight. Storms will likely move off the front but
instability will be weaker the farther to the east and with the
better lift remaining west of the area storms will weaken as they
push into the area. A few storms may make it into the area before
dissipating but most locations should remain dry.
.LONG TERM...(Monday through Saturday)
Issued at 343 AM CDT Sun Apr 24 2016
The front is expected to remain north of the area on Monday as the
upper level trough and surface low push off to the east. Shortwave
upper level ridging will build over the area on Monday. Can not
rule out an isolated shower/rumble of thunder mainly in the
morning hours as isentropic lift spreads across the area ahead of
the ridge, but expect most location to remain dry during the day
on Monday.
Isentropic lift will again develop, mainly over the extreme
southeastern Kansas and far southwestern Missouri Monday night
into Tuesday morning. Instability will start to develop across
the area as Gulf moisture spread north, but a cap will also develop
across the area. The cap does weaken some for an elevated storm,
but it does not go completely away. Did include a chance for
thunderstorms to develop across the western portions of the
forecast area to account for this. Instability for an elevated
storm will be limited so not expecting strong to severe storms at
this time.
An upper level trough will lift across the plains on Tuesday then
to the north of the area on Wednesday. Instability will increase
across the region ahead of this system but so will the cap. So,
besides a few morning storms mentioned above, think the cap will
keep much of the afternoon hours dry. Surface low pressure will
develop across the central Plains and connect with the front that
will stall to the north of the area, with it being a warm front.
As the Low level jet increases Tuesday evening storms are expected
to develop along and just north of the warm front, at this time
the front is expected to remain north of the area and these storms
should too.
As the low lifts to the northeast a cold front will move east
across central Kansas and central Oklahoma late Tuesday afternoon
into Tuesday evening. The cap will weaken enough for storms to
develop along and ahead of the front. They should be able to move
off the front as the front only slowly moves east, resulting in
the potential for supercells. The front will not push east into
the area Tuesday night, but cold pools from the storms could
congeal and keep the storms going to the east, in more of a line
or line segments, pushing into and across the area Tuesday night
into Wednesday morning. Instability will be weaker given the
overnight timing, but will remain strong enough to support a
severe risk across the area Tuesday night and Wednesday. Low level
shear will increase with the approach of the storm system, so all
modes of severe weather will be possible, through large hail and
damaging straight line winds will be the main risk. The front will
push across the region Wednesday with the storms/rain chances
ending Wednesday evening.
Thursday will be a dry day then yet another storm system will
track into and across the region Friday into the weekend bringing
additional rounds for showers and thunderstorms to the region.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1144 PM CDT Sat Apr 23 2016
For the KSGF/KJLN/KBBG tafs: VFR conditions are expected with
increasing south to southeast winds. Low pressure will move into
the Plains with an increasing pressure gradient and sfc winds by
15z. High resolution models support sustained 15-20kt winds with
higher gusts.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...DSA
Area Forecast Discussion
National Weather Service Springfield MO
1158 PM CDT SAT APR 23 2016
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1144 PM CDT Sat Apr 23 2016
For the KSGF/KJLN/KBBG tafs: VFR conditions are expected with
increasing south to southeast winds. Low pressure will move into
the Plains with an increasing pressure gradient and sfc winds by
15z. High resolution models support sustained 15-20kt winds with
higher gusts.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...DSA
Area Forecast Discussion
National Weather Service Springfield MO
1158 PM CDT SAT APR 23 2016
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1144 PM CDT Sat Apr 23 2016
For the KSGF/KJLN/KBBG tafs: VFR conditions are expected with
increasing south to southeast winds. Low pressure will move into
the Plains with an increasing pressure gradient and sfc winds by
15z. High resolution models support sustained 15-20kt winds with
higher gusts.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...DSA
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1152 PM CDT SAT APR 23 2016
.UPDATE...
Issued at 921 PM CDT Sat Apr 23 2016
Going dry forecast the rest of the night still looks good as upper
ridge moves over the area allowing for only a few high clouds to
drift across the area. Still may be some patchy fog tonight, but
think this will be held in check by the wind which should stay up
tonight as the pressure gradient continues to tighten. Only made
minor adjustments to lows based on going temperature trends.
Britt
&&
.SHORT TERM... (Through Late Tonight)
Issued at 255 PM CDT Sat Apr 23 2016
Surface ridge extending from MI southwest into eastern MO will move
eastward. The stratus clouds across southeast IL should continue to
dissipate late this afternoon. Few-scattered diurnal cumulus
clouds, especially across parts of northeast and central MO will
dissipate early this evening with the loss of daytime heating.
Mainly just a little high level cloudiness tonight. Lows tonight
will be warmer than the previous night, mainly due to southeast
surface winds on the backside of the surface ridge. The warmest
temperatures will be across central MO with the coolest temperatures
in southwest IL. Lows tonight will be about 5 to 10 degrees above
normal for late April.
GKS
.LONG TERM... (Sunday through Next Saturday)
Issued at 255 PM CDT Sat Apr 23 2016
Dry and warmer weather to persist on Sunday, but will see an
increase in high clouds as next weather system approaches region.
With gusty south winds will see highs in the upper 70s to low 80s.
Sunday night rain chances to approach region, but models are a bit
slower with onset, so lowered pops just a bit. Then Monday through
Tuesday, frontal boundary to slowly slide south through area with
mainly scattered showers and thunderstorms. Front to stall out
across southern Missouri on Tuesday. Highs will be in the upper 70s
to low 80s on Monday, then dip down into the low 70s to low 80s
Tuesday and Wednesday.
Decent instability north of front Tuesday night, so could see
elevated activity develop and slide along boundary on nose of decent
low level jet. Large hail would be the main threat with this round
of storms.
Models are still indicating decent instability, CAPES in excess of
1500 J/kg and shear with system Wednesday afternoon, Wednesday night
as warm front lifts north through forecast area. All of this still
points to our first real potential severe weather day this spring,
but a lot can happen in 5 days. Stay tuned to further updates.
With everything a bit slower, main cold front to slide through early
on Thursday with precipitation tapering off to just slight chance
pops through Friday. Then extended models showing next system
lifting northeast towards forecast area Friday night and Saturday
with increasing chances of showers and thunderstorms once again.
Once system exits region on Thursday, will see precipitation taper
off. Even though it will be a bit cooler Thursday, highs will still
be a bit above normal in the mid 60s to upper 70s. Extended models
beginning to indicate another system approaching region on Friday,
but timing is hard to pin down. So for now kept slight chance pops.
Byrd
&&
.AVIATION... (For the 06z TAFs through 06z Sunday Night)
Issued at 1152 PM CDT Sat Apr 23 2016
Dry and VFR conditions are still expected at the terminals through
the TAF period. There may be some patchy fog late tonight and
early Sunday over southern Illinois and southeast Missouri. Low
level wind shear is still possible at KUIN and KCOU between 09-15Z
as a 35-40kt low level jet sets up between 1000-2000 feet. Still
expect gusts over 20kts during the late morning and afternoon
hours that will decrease slightly after sunset.
Specifics for KSTL:
Dry and VFR conditions are expected through the TAF period. Gusts
above 20 kts are possible after 18Z on Sunday afternoon.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1047 PM CDT SAT APR 23 2016
.Short Term...(This Evening through Monday Night)
Issued at 309 PM CDT SAT APR 23 2016
Short Term (Tonight through Monday night):
The main concern in the short term will be the potential for a few
strong and isolated severe storms on Sunday evening into Sunday
night. Tonight, however will be much less interesting and quite
pleasant as modest southerly winds will hold temperatures in the mid
50s to lower 60s. The system, an upper level trough, that will bring
thunderstorms to the area Sunday will move from western Wyoming to
near the WY/SD/NE by Saturday night. This will force a cold front into
the western Plains. Thunderstorms will develop along this front
tonight across western Kansas. This storms will progress across
Kansas overnight enhanced by a 50-60kt SSWly nocturnal LLJ. By early
Sunday morning the LLJ will veer to the southwest and storms will
begin to approach northeastern KS and northwestern MO. However,
these storms will be weakening as they approach and there may just
be a few isolated storms or residual shower to make it into the
extreme NW CWA Sunday morning. However, by Sunday afternoon, a dry
line will exist across central Kansas with the attendant cold front
lagging to the west across the western High Plains. Thunderstorms
are expected to develop out ahead of the cold front across central
Kansas during the afternoon and move eastward. These storms will
have the potential to be strong with perhaps isolated severe storms
possible mainly across northwestern MO/northeastern KS where
dewpoints will be near 60 degrees, modest instability of 500-
800J/kg, and steep mid-level lapse rates will exist. However, shear
is not impressive and as previously mentioned instability is merely
modest. Consequently, strong storms will be possible and perhaps
even a marginally severe storm capable of producing large hail or
damaging winds. Storms will weaken Sunday night as storms move into
a more stable environment and the upper level trough continues to
weak as it moves into the Upper Midwest. On Monday, the cold front
associated with the upper level system will sag through the area.
However, will little forcing the front will sag through the area
with little activity expected. The best chance for storms would
occur head of the front where modest instability will reside. Monday
night the cold front will sink south of the area and become
stationary. A few thunderstorms may develop north of the stationary
boundary Monday as a SW 40kt LLJ overrides the boundary. These
thunderstorms may affect the southern CWA depending on the location
of the front.
.Long Term...(Tuesday through Saturday)
Issued at 309 PM CDT SAT APR 23 2016
Tuesday evening and Wednesday will bring another round of showers
and possibly severe thunderstorms to the CWA. The most recent NAM
and GFS runs show Tuesday morning and early afternoon warm and humid
with precipitation mainly staying just south of the WFO. A negatively
tilted low pressure trough stations itself over eastern CO/western KS
Tuesday afternoon. A cold front will move east through Kansas
Wednesday afternoon, and an associated warm front will be located E-W
through our forecast area late Tuesday bringing low- level moisture
with it. Dew point temperatures will range from low 50s north of the
front spreading south to the mid-60s. We will also have decent
instability and shear with CAPE values around 1000-2000 J/kg and
30-50 kt 0-6 km bulk shear. A combination of high CAPE and shear may
lead to potentially severe thunderstorms ahead of the cold front. The
development and location of severe weather will depend on the timing
of convection and the frontal passage, which will become more clear
as we get closer to the event. For now, the GFS and Euro models show
precipitation starting in eastern KS and moving east through the WFO
late Tuesday night through Wednesday morning. Convection could
continue throughout Wednesday as CAPE values are expected to stay
above 1000 J/kg throughout Wednesday afternoon.
High temperatures will continue to be in the mid 70s through
Wednesday, but will drop to the mid-high 60s for Thursday and Friday
after the cold front passes. Low temperatures will drop Thursday and
Friday mornings to the high 40s to low 50s. Thursday is expected to
be dry before another upper low system may cause more precipitation
late Friday into Saturday.
&&
.Aviation...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1046 PM CDT SAT APR 23 2016
VFR conditions expected through much of the fcst period. Latest
model runs suggesting the bulk of thunderstorm activity will remain
west of the forecast area. Cannot rule out some isolated convection
holding itself together as it moves east off the dryline in central
Kansas...but activity will be moving into a more and more unfavorable
environment with further eastward progress. In any event...have
inserted a VCTS mention for STJ...and later updates can address the
KC terminals if trends begin to change. The other main concern
remains the likelihood for LLWS early this morning thanks to a strong
southwesterly low-level jet...and have maintained mention for all
terminals with the 06z package. Meanwhile...southerly winds of 10-15
kts overnight will increase after 16z on Sunday with gusts up to 30
kts possible during the afternoon hours.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Short Term...73
Long Term...Chandler/CDB
Aviation...32
Area Forecast Discussion...Updated
National Weather Service Saint Louis MO
921 PM CDT SAT APR 23 2016
.UPDATE...
Issued at 921 PM CDT Sat Apr 23 2016
Going dry forecast the rest of the night still looks good as upper
ridge moves over the area allowing for only a few high clouds to
drift across the area. Still may be some patchy fog tonight, but
think this will be held in check by the wind which should stay up
tonight as the pressure gradient continues to tighten. Only made
minor adjustments to lows based on going temperature trends.
Britt
&&
.SHORT TERM... (Through Late Tonight)
Issued at 255 PM CDT Sat Apr 23 2016
Surface ridge extending from MI southwest into eastern MO will move
eastward. The stratus clouds across southeast IL should continue to
dissipate late this afternoon. Few-scattered diurnal cumulus
clouds, especially across parts of northeast and central MO will
dissipate early this evening with the loss of daytime heating.
Mainly just a little high level cloudiness tonight. Lows tonight
will be warmer than the previous night, mainly due to southeast
surface winds on the backside of the surface ridge. The warmest
temperatures will be across central MO with the coolest temperatures
in southwest IL. Lows tonight will be about 5 to 10 degrees above
normal for late April.
GKS
.LONG TERM... (Sunday through Next Saturday)
Issued at 255 PM CDT Sat Apr 23 2016
Dry and warmer weather to persist on Sunday, but will see an
increase in high clouds as next weather system approaches region.
With gusty south winds will see highs in the upper 70s to low 80s.
Sunday night rain chances to approach region, but models are a bit
slower with onset, so lowered pops just a bit. Then Monday through
Tuesday, frontal boundary to slowly slide south through area with
mainly scattered showers and thunderstorms. Front to stall out
across southern Missouri on Tuesday. Highs will be in the upper 70s
to low 80s on Monday, then dip down into the low 70s to low 80s
Tuesday and Wednesday.
Decent instability north of front Tuesday night, so could see
elevated activity develop and slide along boundary on nose of decent
low level jet. Large hail would be the main threat with this round
of storms.
Models are still indicating decent instability, CAPES in excess of
1500 J/kg and shear with system Wednesday afternoon, Wednesday night
as warm front lifts north through forecast area. All of this still
points to our first real potential severe weather day this spring,
but a lot can happen in 5 days. Stay tuned to further updates.
With everything a bit slower, main cold front to slide through early
on Thursday with precipitation tapering off to just slight chance
pops through Friday. Then extended models showing next system
lifting northeast towards forecast area Friday night and Saturday
with increasing chances of showers and thunderstorms once again.
Once system exits region on Thursday, will see precipitation taper
off. Even though it will be a bit cooler Thursday, highs will still
be a bit above normal in the mid 60s to upper 70s. Extended models
beginning to indicate another system approaching region on Friday,
but timing is hard to pin down. So for now kept slight chance pops.
Byrd
&&
.AVIATION... (For the 00z TAFs through 00z Sunday Evening)
Issued at 650 PM CDT Sat Apr 23 2016
Dry and VFR conditions are expected at the terminals. There may be
some patchy fog late tonight and early Sunday over southern
Illinois and southeast Missouri. Low level wind shear is still
possible at KUIN and KCOU between 09-15Z as a 35-40kt low level
jet sets up between 1000-2000 feet. This threat will end by mid
morning as mixing begins and the surface winds begin to pick up.
Do expect some gusts above 20kts during the late morning and
afternoon hours.
Specifics for KSTL: Dry and VFR conditions are expected the next
30 hours. Southerly winds will increase after 18Z on Sunday
afternoon with wind gusts over 20kts.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
705 PM CDT SAT APR 23 2016
.SHORT TERM... (Through Late Tonight)
Issued at 255 PM CDT Sat Apr 23 2016
Surface ridge extending from MI southwest into eastern MO will move
eastward. The stratus clouds across southeast IL should continue to
dissipate late this afternoon. Few-scattered diurnal cumulus
clouds, especially across parts of northeast and central MO will
dissipate early this evening with the loss of daytime heating.
Mainly just a little high level cloudiness tonight. Lows tonight
will be warmer than the previous night, mainly due to southeast
surface winds on the backside of the surface ridge. The warmest
temperatures will be across central MO with the coolest temperatures
in southwest IL. Lows tonight will be about 5 to 10 degrees above
normal for late April.
GKS
.LONG TERM... (Sunday through Next Saturday)
Issued at 255 PM CDT Sat Apr 23 2016
Dry and warmer weather to persist on Sunday, but will see an
increase in high clouds as next weather system approaches region.
With gusty south winds will see highs in the upper 70s to low 80s.
Sunday night rain chances to approach region, but models are a bit
slower with onset, so lowered pops just a bit. Then Monday through
Tuesday, frontal boundary to slowly slide south through area with
mainly scattered showers and thunderstorms. Front to stall out
across southern Missouri on Tuesday. Highs will be in the upper 70s
to low 80s on Monday, then dip down into the low 70s to low 80s
Tuesday and Wednesday.
Decent instability north of front Tuesday night, so could see
elevated activity develop and slide along boundary on nose of decent
low level jet. Large hail would be the main threat with this round
of storms.
Models are still indicating decent instability, CAPES in excess of
1500 J/kg and shear with system Wednesday afternoon, Wednesday night
as warm front lifts north through forecast area. All of this still
points to our first real potential severe weather day this spring,
but a lot can happen in 5 days. Stay tuned to further updates.
With everything a bit slower, main cold front to slide through early
on Thursday with precipitation tapering off to just slight chance
pops through Friday. Then extended models showing next system
lifting northeast towards forecast area Friday night and Saturday
with increasing chances of showers and thunderstorms once again.
Once system exits region on Thursday, will see precipitation taper
off. Even though it will be a bit cooler Thursday, highs will still
be a bit above normal in the mid 60s to upper 70s. Extended models
beginning to indicate another system approaching region on Friday,
but timing is hard to pin down. So for now kept slight chance pops.
Byrd
&&
.AVIATION... (For the 00z TAFs through 00z Sunday Evening)
Issued at 650 PM CDT Sat Apr 23 2016
Dry and VFR conditions are expected at the terminals. There may be
some patchy fog late tonight and early Sunday over southern
Illinois and southeast Missouri. Low level wind shear is still
possible at KUIN and KCOU between 09-15Z as a 35-40kt low level
jet sets up between 1000-2000 feet. This threat will end by mid
morning as mixing begins and the surface winds begin to pick up.
Do expect some gusts above 20kts during the late morning and
afternoon hours.
Specifics for KSTL: Dry and VFR conditions are expected the next
30 hours. Southerly winds will increase after 18Z on Sunday
afternoon with wind gusts over 20kts.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
629 PM CDT SAT APR 23 2016
.Short Term...(This Evening through Monday Night)
Issued at 309 PM CDT SAT APR 23 2016
Short Term (Tonight through Monday night):
The main concern in the short term will be the potential for a few
strong and isolated severe storms on Sunday evening into Sunday
night. Tonight, however will be much less interesting and quite
pleasant as modest southerly winds will hold temperatures in the mid
50s to lower 60s. The system, an upper level trough, that will bring
thunderstorms to the area Sunday will move from western Wyoming to
near the WY/SD/NE by Saturday night. This will force a cold front into
the western Plains. Thunderstorms will develop along this front
tonight across western Kansas. This storms will progress across
Kansas overnight enhanced by a 50-60kt SSWly nocturnal LLJ. By early
Sunday morning the LLJ will veer to the southwest and storms will
begin to approach northeastern KS and northwestern MO. However,
these storms will be weakening as they approach and there may just
be a few isolated storms or residual shower to make it into the
extreme NW CWA Sunday morning. However, by Sunday afternoon, a dry
line will exist across central Kansas with the attendant cold front
lagging to the west across the western High Plains. Thunderstorms
are expected to develop out ahead of the cold front across central
Kansas during the afternoon and move eastward. These storms will
have the potential to be strong with perhaps isolated severe storms
possible mainly across northwestern MO/northeastern KS where
dewpoints will be near 60 degrees, modest instability of 500-
800J/kg, and steep mid-level lapse rates will exist. However, shear
is not impressive and as previously mentioned instability is merely
modest. Consequently, strong storms will be possible and perhaps
even a marginally severe storm capable of producing large hail or
damaging winds. Storms will weaken Sunday night as storms move into
a more stable environment and the upper level trough continues to
weak as it moves into the Upper Midwest. On Monday, the cold front
associated with the upper level system will sag through the area.
However, will little forcing the front will sag through the area
with little activity expected. The best chance for storms would
occur head of the front where modest instability will reside. Monday
night the cold front will sink south of the area and become
stationary. A few thunderstorms may develop north of the stationary
boundary Monday as a SW 40kt LLJ overrides the boundary. These
thunderstorms may affect the southern CWA depending on the location
of the front.
.Long Term...(Tuesday through Saturday)
Issued at 309 PM CDT SAT APR 23 2016
Tuesday evening and Wednesday will bring another round of showers
and possibly severe thunderstorms to the CWA. The most recent NAM
and GFS runs show Tuesday morning and early afternoon warm and humid
with precipitation mainly staying just south of the WFO. A negatively
tilted low pressure trough stations itself over eastern CO/western KS
Tuesday afternoon. A cold front will move east through Kansas
Wednesday afternoon, and an associated warm front will be located E-W
through our forecast area late Tuesday bringing low- level moisture
with it. Dew point temperatures will range from low 50s north of the
front spreading south to the mid-60s. We will also have decent
instability and shear with CAPE values around 1000-2000 J/kg and
30-50 kt 0-6 km bulk shear. A combination of high CAPE and shear may
lead to potentially severe thunderstorms ahead of the cold front. The
development and location of severe weather will depend on the timing
of convection and the frontal passage, which will become more clear
as we get closer to the event. For now, the GFS and Euro models show
precipitation starting in eastern KS and moving east through the WFO
late Tuesday night through Wednesday morning. Convection could
continue throughout Wednesday as CAPE values are expected to stay
above 1000 J/kg throughout Wednesday afternoon.
High temperatures will continue to be in the mid 70s through
Wednesday, but will drop to the mid-high 60s for Thursday and Friday
after the cold front passes. Low temperatures will drop Thursday and
Friday mornings to the high 40s to low 50s. Thursday is expected to
be dry before another upper low system may cause more precipitation
late Friday into Saturday.
&&
.Aviation...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 629 PM CDT SAT APR 23 2016
VFR conditions anticipated through the fcst period with modest south
winds of 10-15 kts expected through the overnight before increasing
after 16z. Further aloft...a strong southwesterly low-level jet of
roughly 45 kts will lead to increasing LLWS concerns after 06z and a
mention has been added for all forecast locations. Precip chances in
the form of shwrs/storms look to increase after 21z...however the
mostly likely location right now appears to be STJ based on expected
dryline configuration. Will consider adding further south with the
next forecast issuance.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Short Term...73
Long Term...Chandler/CDB
Aviation...32
Area Forecast Discussion
National Weather Service Springfield MO
616 PM CDT SAT APR 23 2016
...00z Aviation Update...
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 616 PM CDT Sat Apr 23 2016
VFR conditions will again persist through this TAF cycle. Winds
have become southerly (as advertised) during the day today.
Surface winds will steadily increase through Sunday ahead of a
passing system over the plains. Gusty southerly winds can be
expected for SGF and JLN by Sunday afternoon and should continue
through the end of the period.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Frye
Area Forecast Discussion
National Weather Service Springfield MO
616 PM CDT SAT APR 23 2016
...00z Aviation Update...
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 616 PM CDT Sat Apr 23 2016
VFR conditions will again persist through this TAF cycle. Winds
have become southerly (as advertised) during the day today.
Surface winds will steadily increase through Sunday ahead of a
passing system over the plains. Gusty southerly winds can be
expected for SGF and JLN by Sunday afternoon and should continue
through the end of the period.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Frye
Area Forecast Discussion
National Weather Service Springfield MO
328 PM CDT SAT APR 23 2016
...Beautiful Weather This Weekend...Increasing Confidence for
Strong to Severe Storms Next Week...
.SHORT TERM...(This evening through Sunday Night)
Issued at 249 PM CDT Sat Apr 23 2016
Very pleasant weather was being observed across the entire area
this afternoon with sunny skies and light winds. Temperatures have
warmed up into the middle and upper 70s area wide. Another nice
evening is on the way followed by another nice day on Sunday with
highs around 80. It will be breezy as a storm system develops
across the High Plains region into the northern Plains. A strong
pressure gradient will cause southerly winds possibly gusting up
to 30 mph at times over the western half of the area.
Strong to severe convection will develop just our northwest across
Kansas by tomorrow evening along a pseudo front and dry line.
This convection will try to move eastward Sunday night but run out
of energy and atmospheric support. Will continue to mention the
possibility of a strong storm or two possibly reaching portions
of southeast Kansas and extreme western Missouri very late Sunday
night. Otherwise the convection will decrease to spotty showers
and isolated thunder across the area by Monday morning.
.LONG TERM...(Monday through Saturday)
Issued at 249 PM CDT Sat Apr 23 2016
Monday will be partly cloudy to mostly cloudy and more humid. The
front that ran out of energy and support Sunday night will stall
out across the area or just northwest of the area on Monday. With
this boundary in the general area with weak forcing and some weak
instability to work with...will continue a chance of a few
scattered showers and isolated thunder Monday through early on
Tuesday. This stalling out of the boundary will be key to allowing
low level and mid level moisture to continue to increase across
the region.
The main concern and attention will be the stronger storm system
developing on Tuesday and Wednesday. A good agreement with the
forecast models show a strong negatively tilted trough moving out
of the Rocky Mountains to the Central Plains on Tuesday afternoon.
Surface dewpoints will climb into the middle 60s across the region
with forecast cape somewhere from 3000 to 4000 J/KG. Bulk shear
magnitudes will be around 35 knots Tuesday evening and slow
increasing Tuesday night into Wednesday. There may be initially a
strong cap Tuesday afternoon. Still a few questions on timing of
when convection will develop or move into the area Tuesday evening
and Tuesday night. But confidence is slowly increasing that the
region will see severe weather late Tuesday through Wednesday.
The ECMWF is a little further southeast of the position than the
GFS with the upper level system and storm system. All models show
a possible outbreak of severe weather developing to our west late
Tuesday afternoon into the evening. This convection will begin to
move into our southeast Kansas counties and extreme western
Missouri very late Tuesday evening into the overnight hours. All
modes of severe weather appear possible west of the Highway 65
corridor with large hail...damaging winds...and a few tornadoes
possible.
The convection may be ongoing or decreasing by early Wednesday
morning. The question remains if the atmosphere will be able to
destabilize again by midday or Wednesday afternoon. The models
have slowed down the progression of the dryline or front which now
may hang out across western Missouri on Wednesday. The better
potential for severe weather on Wednesday will remain along and
east of Highway 65 Wednesday afternoon with all modes of severe
weather possible again. Areawide total forecast rainfall will
average about an inch to up to an inch and half possible.
The front finally moves through late Wednesday night and moves
out the showers and storms to the east. The front stalls out to
our south on Thursday with dry weather expected across the area.
The boundary moves northward as a warm front on Friday and
Saturday bringing another round of showers and storms to the
region late in the week. The weather pattern looks active and
storm heading into next weekend as well.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1159 AM CDT Sat Apr 23 2016
VFR conditions are expected through the period as surface high
pressure continues to drift eastward and an upper level ridge
moves across the area. Main forecast concern is gusty winds
beginning after sunrise on Sunday as the next approaching system
begins to tighten up the surface pressure gradient. Winds should
develop gusts after 13z at KSGF/KJLN but believe that it will be
later in the afternoon...after the end of the forecast
period...for KBBG.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Gaede
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
310 PM CDT SAT APR 23 2016
.Short Term...(This Evening through Monday Night)
Issued at 309 PM CDT SAT APR 23 2016
Short Term (Tonight through Monday night):
The main concern in the short term will be the potential for a few
strong and isolated severe storms on Sunday evening into Sunday
night. Tonight, however will be much less interesting and quite
pleasant as modest southerly winds will hold temperatures in the mid
50s to lower 60s. The system, an upper level trough, that will bring
thunderstorms to the area Sunday will move from western Wyoming to
near the WY/SD/NE by Saturday night. This will force a cold front into
the western Plains. Thunderstorms will develop along this front
tonight across western Kansas. This storms will progress across
Kansas overnight enhanced by a 50-60kt SSWly nocturnal LLJ. By early
Sunday morning the LLJ will veer to the southwest and storms will
begin to approach northeastern KS and northwestern MO. However,
these storms will be weakening as they approach and there may just
be a few isolated storms or residual shower to make it into the
extreme NW CWA Sunday morning. However, by Sunday afternoon, a dry
line will exist across central Kansas with the attendant cold front
lagging to the west across the western High Plains. Thunderstorms
are expected to develop out ahead of the cold front across central
Kansas during the afternoon and move eastward. These storms will
have the potential to be strong with perhaps isolated severe storms
possible mainly across northwestern MO/northeastern KS where
dewpoints will be near 60 degrees, modest instability of 500-
800J/kg, and steep mid-level lapse rates will exist. However, shear
is not impressive and as previously mentioned instability is merely
modest. Consequently, strong storms will be possible and perhaps
even a marginally severe storm capable of producing large hail or
damaging winds. Storms will weaken Sunday night as storms move into
a more stable environment and the upper level trough continues to
weak as it moves into the Upper Midwest. On Monday, the cold front
associated with the upper level system will sag through the area.
However, will little forcing the front will sag through the area
with little activity expected. The best chance for storms would
occur head of the front where modest instability will reside. Monday
night the cold front will sink south of the area and become
stationary. A few thunderstorms may develop north of the stationary
boundary Monday as a SW 40kt LLJ overrides the boundary. These
thunderstorms may affect the southern CWA depending on the location
of the front.
.Long Term...(Tuesday through Saturday)
Issued at 309 PM CDT SAT APR 23 2016
Tuesday evening and Wednesday will bring another round of showers
and possibly severe thunderstorms to the CWA. The most recent NAM
and GFS runs show Tuesday morning and early afternoon warm and humid
with precipitation mainly staying just south of the WFO. A negatively
tilted low pressure trough stations itself over eastern CO/western KS
Tuesday afternoon. A cold front will move east through Kansas
Wednesday afternoon, and an associated warm front will be located E-W
through our forecast area late Tuesday bringing low- level moisture
with it. Dew point temperatures will range from low 50s north of the
front spreading south to the mid-60s. We will also have decent
instability and shear with CAPE values around 1000-2000 J/kg and
30-50 kt 0-6 km bulk shear. A combination of high CAPE and shear may
lead to potentially severe thunderstorms ahead of the cold front. The
development and location of severe weather will depend on the timing
of convection and the frontal passage, which will become more clear
as we get closer to the event. For now, the GFS and Euro models show
precipitation starting in eastern KS and moving east through the WFO
late Tuesday night through Wednesday morning. Convection could
continue throughout Wednesday as CAPE values are expected to stay
above 1000 J/kg throughout Wednesday afternoon.
High temperatures will continue to be in the mid 70s through
Wednesday, but will drop to the mid-high 60s for Thursday and Friday
after the cold front passes. Low temperatures will drop Thursday and
Friday mornings to the high 40s to low 50s. Thursday is expected to
be dry before another upper low system may cause more precipitation
late Friday into Saturday.
&&
.Aviation...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1230 PM CDT SAT APR 23 2016
VFR conds will prevail through the pd with mainly just sct high
clouds expected. Winds will pick up out of the south this afternoon
to 10-15kts with gusts to around 20kts. Winds will lose their gusts
this evening but still remain around 10-15kts. However, tomorrow
morning winds will again increase to 15-20kts with gusts to 25-30kts.
LLWS may be a marginal concern tonight as winds at 2kft will be out
of the SSW at 35-40kts btn 06Z-14Z and, may need to be added to the
TAF at the 00Z issuance.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Short Term...73
Long Term...Chandler/CDB
Aviation...73
Area Forecast Discussion
National Weather Service Saint Louis MO
257 PM CDT SAT APR 23 2016
.SHORT TERM... (Through Late Tonight)
Issued at 255 PM CDT Sat Apr 23 2016
Surface ridge extending from MI southwest into eastern MO will move
eastward. The stratus clouds across southeast IL should continue to
dissipate late this afternoon. Few-scattered diurnal cumulus
clouds, especially across parts of northeast and central MO will
dissipate early this evening with the loss of daytime heating.
Mainly just a little high level cloudiness tonight. Lows tonight
will be warmer than the previous night, mainly due to southeast
surface winds on the backside of the surface ridge. The warmest
temperatures will be across central MO with the coolest temperatures
in southwest IL. Lows tonight will be about 5 to 10 degrees above
normal for late April.
GKS
.LONG TERM... (Sunday through Next Saturday)
Issued at 255 PM CDT Sat Apr 23 2016
Dry and warmer weather to persist on Sunday, but will see an
increase in high clouds as next weather system approaches region.
With gusty south winds will see highs in the upper 70s to low 80s.
Sunday night rain chances to approach region, but models are a bit
slower with onset, so lowered pops just a bit. Then Monday through
Tuesday, frontal boundary to slowly slide south through area with
mainly scattered showers and thunderstorms. Front to stall out
across southern Missouri on Tuesday. Highs will be in the upper 70s
to low 80s on Monday, then dip down into the low 70s to low 80s
Tuesday and Wednesday.
Decent instability north of front Tuesday night, so could see
elevated activity develop and slide along boundary on nose of decent
low level jet. Large hail would be the main threat with this round
of storms.
Models are still indicating decent instability, CAPES in excess of
1500 J/kg and shear with system Wednesday afternoon, Wednesday night
as warm front lifts north through forecast area. All of this still
points to our first real potential severe weather day this spring,
but a lot can happen in 5 days. Stay tuned to further updates.
With everything a bit slower, main cold front to slide through early
on Thursday with precipitation tapering off to just slight chance
pops through Friday. Then extended models showing next system
lifting northeast towards forecast area Friday night and Saturday
with increasing chances of showers and thunderstorms once again.
Once system exits region on Thursday, will see precipitation taper
off. Even though it will be a bit cooler Thursday, highs will still
be a bit above normal in the mid 60s to upper 70s. Extended models
beginning to indicate another system approaching region on Friday,
but timing is hard to pin down. So for now kept slight chance pops.
Byrd
&&
.AVIATION... (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1104 AM CDT Sat Apr 23 2016
Surface ridge extending from the Great Lakes region southwest
into eastern MO will shift eastward this period. The low level
cloudiness over eastern IA into northeast MO should remain north
of UIN this afternoon. The stratus cloudiness across southeast IL
should gradually dissipate this afternoon with daytime heating,
mixing and drying and remain east of the St Louis metro area.
There may be a few diurnal cumulus clouds at the taf sites this
afternoon. There will be a little high level cloudiness late
tonight and Sunday morning. Southeasterly surface winds should
strengthen at UIN and COU through the forecast period as the
surface pressure gradient gradually tightens, becoming more
southerly on Sunday. Light northeast wind in the St Louis metro
area will also strengthen as well through the period, veering
around to a southeast direction by early this evening, then
southerly Sunday morning. There will be some LLWS conditions in
UIN and COU very late tonight and early Sunday morning as a
southwesterly low level jet translates eastward into northwest MO
with both speed and directional shear in the lowest 1000 feet.
Specifics for KSTL: Stratus clouds across southeast IL should
gradually dissipate this afternoon and remain east-southeast of
STL. Few diurnal cumulus clouds may develop this afternoon due to
daytime heating, then dissipate early this evening. There will be
some high level cloudiness late tonight and Sunday. Light
northeast wind will increase in speed to 8-10 kts by late this
afternoon or early this evening as it veers around to a southeast
direction. The surface wind will become southerly Sunday morning
and possibly gusty Sunday afternoon.
GKS
&&
.PRELIMINARY POINT TEMPS/POPS...
Saint Louis 55 82 63 81 / 0 0 20 30
Quincy 56 81 61 79 / 5 5 30 30
Columbia 57 81 60 78 / 5 5 20 30
Jefferson City 58 82 61 80 / 5 5 20 30
Salem 51 79 60 80 / 0 0 10 20
Farmington 52 79 60 79 / 0 0 10 20
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1230 PM CDT SAT APR 23 2016
.Discussion...
Issued at 412 AM CDT SAT APR 23 2016
Today - Tonight:
In the very near term will be dealing with patchy dense fog over the
northeast 1/2 of the CWA. The fog and stratus is forming under a
surface ridge with river valleys and low lying areas the most
susceptible. The latest NAM/RAP 925mb condensation pressure deficit
prog best depict the low clouds with the SREF favoring more
widespread dense fog further north in IA.
Otherwise, for today expect a nice warm up as pressure falls over
the Central Plains induce increasing southerly winds. Should see
decent mixing with a dry adiabatic lapse rate yielding highs around
10 degrees above average. Upper level ridging spreading east into
the CWA will provide for continued dry conditions.
Increasing warm air advection aloft will ensue across KS and NE this
evening with scattered elevated convection possibly grazing far
northwest MO towards sunrise Sunday morning. Any convection which
reaches this region should fall apart Sunday morning with convective
debris and mid level accas likely lingering over the western CWA
into the afternoon.
Sunday - Sunday night:
The weather will become more interesting late Sunday afternoon into
the evening as an upper level closed low migrates into SD/NE. A
negatively tilted shortwave trough is progged to rotate from under
the upper low and lift northeast across KS and NE during the
afternoon. A moderately strong low level jet around 45kts will pull
deeper low level moisture ahead of a north-south dryline which will
anchor over central KS and far western OK. Expect to see scattered
strong/severe convection form along the dryline by mid/late
afternoon and track quickly northeast. Far northwest MO stands the
best chance of seeing active convection. Surface based CAPEs around
1500 J/kg and 0-6km shear around 40kts will support
strong/marginally severe storms over this area. All models strongly
suggest the dryline will move little to the east so the severe
threat in the CWA will likely be limited to far northwest MO.
Convection will weaken and decrease in coverage as it moves east
through the CWA with the far southeastern counties receiving the
least QPF.
Monday - Friday:
A fairly active period with two more closed upper lows likely
affecting the region. While Monday initially looked relatively quiet
as the Upper MS Valley system pulls away there is some concern that
some afternoon convection could form along the remnants of a stalled
surface boundary. The limiting factor will be increasing mid level
heights and a lack of upper support. Nonetheless with a front in the
CWA will need to be vigilant.
As we`ve been discussing over the past few days a second and
stronger upper system will become a factor and play a significant
role in our weather by Tuesday night and continuing into Wednesday.
Medium range operational models continue to eject a negatively
tilted shortwave through KS and MO. There is every reason to believe
a west-east frontal boundary will be in the vicinity with this
feature lifting north and through the CWA. Low-level moisture will
not be a problem with low/mid 60 dewpoints likely south of the front
and spreading northward. The GFS indicates 2000-3000 J/kg of CAPE
could be available with 30-40kt 0-6km shear so severe storms are a
growing concern. As always timing of the front and convective
development will determine where severe will occur but our CWA is
currently within the window of opportunity.
Convection could linger well into Wednesday as the upper low opens
up and lifts through NE/KS/IA/MO.
Thursday looks quiet as we`ll be between systems. The third system
we`ll be keeping an eye on will be yet another closed upper low.
This feature may not be a factor until late Friday.
Through out this period expect to see above average temperatures with
an overall increase in humidity.
&&
.Aviation...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1230 PM CDT SAT APR 23 2016
VFR conds will prevail through the pd with mainly just sct high
clouds expected. Winds will pick up out of the south this afternoon
to 10-15kts with gusts to around 20kts. Winds will lose their gusts
this evening but still remain around 10-15kts. However, tomorrow
morning winds will again increase to 15-20kts with gusts to 25-30kts.
LLWS may be a marginal concern tonight as winds at 2kft will be out
of the SSW at 35-40kts btn 06Z-14Z and, may need to be added to the
TAF at the 00Z issuance.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...MJ
Aviation...73
Area Forecast Discussion
National Weather Service Springfield MO
1206 PM CDT SAT APR 23 2016
.SHORT TERM...(Today through Sunday)
Issued at 330 AM CDT Sat Apr 23 2016
An upper level ridge is currently building over the region early
this morning and will be centered over the area by tonight. As an
upper level trough tracks east into the northern Plains on Sunday
the ridge will start to spread off Sunday night.
Warm and dry conditions will occur through much of this weekend
as highs warm into the upper 70s to the lower 80s both afternoons.
Sunny skies will occur today with partly cloudy skies occurring on
Sunday. Gusty southerly winds will develop Sunday afternoon as
surface low pressure develops across the central Plains ahead of
the upper level low. Wind gusts over 30 mph can be expected for
locations generally along and west of Hwy 65 Sunday afternoon.
.LONG TERM...(Sunday night through Friday)
Issued at 330 AM CDT Sat Apr 23 2016
As the upper level low tracks east storms are expected to develop
to the west and northwest of the area along a cold front Sunday
evening. The front will then drop to the southeast into the area
Sunday night into Monday. The better lift and instability will
remain to the northwest and north of the area as the upper level
trough remains well north of the area. There will be an
instability gradient that sets up close to the far northwestern
portions of the area, so storms will be weakening as they move
southeast into the area, but a few strong storms may still be
possible generally northwest of a Pittsburg KS to Nevada MO line
Sunday night into early Monday morning. Coverage in storms will be
decreasing as the storms move into the area and will be isolated
to scattered in nature and many locations will remain dry. It is
also possible the storms dissipate just to the northwest of the
area.
As the front moves south through the area on Monday a few
thunderstorms will be possible, but overall most locations will
remain dry as coverage will be very limited with this activity.
Instability is expected to remain on the weak side, therefore,
not expecting a severe risk Monday.
Another upper level low will push into the northwestern U.S.
Sunday then dig to the south into the southwestern U.S. Monday
then lift to the northeast across the plains by Wednesday. As the
upper level low lifts to the northeast, the front that moves
south through the region Sunday night into Monday will lift back
to the north as a warm front Monday night into Tuesday morning.
Scattered storm chances will occur again along the front as it
lifts north.
Instability will then increase across the region on Tuesday ahead
of the approaching storm system, but a strong cap will also
develop across the area. The strong lift with this system will
remain well west of the area through the day on Tuesday, Therefore
most of the day should be dry after the warm front lifts north of
the area.
Storms are expected to develop across central Kansas
to the south into central Texas Tuesday evening along a cold
front. The front will then track east Tuesday night into Wednesday
Wednesday across the area. There is still some question on the
exact timing of the front but it will be at some point during the
day on Wednesday. There will be a severe risk with the storms
overnight Tuesday into Wednesday as the gulf moisture and an
unstable air mass will be in place across the area, large hail and
strong winds will be the main risk.
As the system moves off to the east mostly dry weather will occur
on Thursday. Then another system will begin to track into the
region Friday into the start of the weekend brining additional
chances for thunderstorms to the area.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1159 AM CDT Sat Apr 23 2016
VFR conditions are expected through the period as surface high
pressure continues to drift eastward and an upper level ridge
moves across the area. Main forecast concern is gusty winds
beginning after sunrise on Sunday as the next approaching system
begins to tighten up the surface pressure gradient. Winds should
develop gusts after 13z at KSGF/KJLN but believe that it will be
later in the afternoon...after the end of the forecast
period...for KBBG.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...Gaede
Area Forecast Discussion
National Weather Service Springfield MO
1206 PM CDT SAT APR 23 2016
.SHORT TERM...(Today through Sunday)
Issued at 330 AM CDT Sat Apr 23 2016
An upper level ridge is currently building over the region early
this morning and will be centered over the area by tonight. As an
upper level trough tracks east into the northern Plains on Sunday
the ridge will start to spread off Sunday night.
Warm and dry conditions will occur through much of this weekend
as highs warm into the upper 70s to the lower 80s both afternoons.
Sunny skies will occur today with partly cloudy skies occurring on
Sunday. Gusty southerly winds will develop Sunday afternoon as
surface low pressure develops across the central Plains ahead of
the upper level low. Wind gusts over 30 mph can be expected for
locations generally along and west of Hwy 65 Sunday afternoon.
.LONG TERM...(Sunday night through Friday)
Issued at 330 AM CDT Sat Apr 23 2016
As the upper level low tracks east storms are expected to develop
to the west and northwest of the area along a cold front Sunday
evening. The front will then drop to the southeast into the area
Sunday night into Monday. The better lift and instability will
remain to the northwest and north of the area as the upper level
trough remains well north of the area. There will be an
instability gradient that sets up close to the far northwestern
portions of the area, so storms will be weakening as they move
southeast into the area, but a few strong storms may still be
possible generally northwest of a Pittsburg KS to Nevada MO line
Sunday night into early Monday morning. Coverage in storms will be
decreasing as the storms move into the area and will be isolated
to scattered in nature and many locations will remain dry. It is
also possible the storms dissipate just to the northwest of the
area.
As the front moves south through the area on Monday a few
thunderstorms will be possible, but overall most locations will
remain dry as coverage will be very limited with this activity.
Instability is expected to remain on the weak side, therefore,
not expecting a severe risk Monday.
Another upper level low will push into the northwestern U.S.
Sunday then dig to the south into the southwestern U.S. Monday
then lift to the northeast across the plains by Wednesday. As the
upper level low lifts to the northeast, the front that moves
south through the region Sunday night into Monday will lift back
to the north as a warm front Monday night into Tuesday morning.
Scattered storm chances will occur again along the front as it
lifts north.
Instability will then increase across the region on Tuesday ahead
of the approaching storm system, but a strong cap will also
develop across the area. The strong lift with this system will
remain well west of the area through the day on Tuesday, Therefore
most of the day should be dry after the warm front lifts north of
the area.
Storms are expected to develop across central Kansas
to the south into central Texas Tuesday evening along a cold
front. The front will then track east Tuesday night into Wednesday
Wednesday across the area. There is still some question on the
exact timing of the front but it will be at some point during the
day on Wednesday. There will be a severe risk with the storms
overnight Tuesday into Wednesday as the gulf moisture and an
unstable air mass will be in place across the area, large hail and
strong winds will be the main risk.
As the system moves off to the east mostly dry weather will occur
on Thursday. Then another system will begin to track into the
region Friday into the start of the weekend brining additional
chances for thunderstorms to the area.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1159 AM CDT Sat Apr 23 2016
VFR conditions are expected through the period as surface high
pressure continues to drift eastward and an upper level ridge
moves across the area. Main forecast concern is gusty winds
beginning after sunrise on Sunday as the next approaching system
begins to tighten up the surface pressure gradient. Winds should
develop gusts after 13z at KSGF/KJLN but believe that it will be
later in the afternoon...after the end of the forecast
period...for KBBG.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...Gaede
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1140 AM CDT SAT APR 23 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 350 AM CDT Sat Apr 23 2016
Focus today will be clouds and temps.
Sfc ridge will continue to drift ewd today, allowing sly winds to
return to wrn portions of the CWA. Winds elsewhere are expected to
remain sely to ely.
The area of clouds currently just E of the CWA shud remain E.
However, some clouds may drift into ern portions of the CWA mainly
this morning until the ridge pushes them out of the area.
A secondary ridge axis over nrn portions of the CWA is expected to
be the focus for FG/stratus this morning. There is still uncertainty
regarding how widespread any FG will be, as well as any stratus. The
additional moisture within the bndy layer across this region shud
allow for at least sct clouds this morning, dissipating thru the
afternoon.
All of this leads to a rather complex temp forecast for today. For
ern portions of the CWA, have kept temps cooler where the ridge axis
will remain in place longer. Areas under this ridge yesterday saw
temps in the upper 60s, however, believe there will be less cloud
cover today. Believe the warmer temps will build into wrn portions
of the CWA where winds will become sly as well as the thermal ridge
building into this area. Have gone with trends close to a blend of
the RAP and local 4km WRF, which has been a good mix in these
setups. Did trend slightly cooler than this blend across nrn
portions of the CWA where more questions exist regarding cloud cover
today.
Tilly
.LONG TERM... (Tonight through Friday)
Issued at 350 AM CDT Sat Apr 23 2016
An upper level longwave RIDGE axis will persist over the Plains
thru much of next week, with upper longwave TROFs on the west and
east coasts. A series of strong Pacific storms will run thru this
RIDGE, being dropped off from the west coast TROF and being picked
up by the east coast TROF a few days later, with an overall track to
the E-NE thru our region. It would seem that each successive storm
system will track a bit further south than its predecessor.
The first storm system is slated to track to our north late Sunday
and into Monday, and will be mostly a glancing blow to our region as
a result, with what forms mostly upstream initially to our northwest
as it is thrown in our direction and largely weakens as it moves in.
This convection may also create additional boundaries during Monday
afternoon and early evening to maintain the threat for showers and
thunderstorms.
In the wake of this first storm system, a cold front will drop down
late Monday night into Tuesday and will maintain a low chance for
rain.
The second Pacific storm system will be more of a direct hit as it
will initially correspond well with the surface frontal boundary
buckling north as a warm front Wednesday morning. This should
result in elevated storms with hail as their primary threat during
that time.
Heading into Wednesday afternoon and evening, it will depend heavily
on how far north the front gets. Models have been trending with
less northward progress from 24hrs ago, but anywhere to the south of
it will have plenty of instability and moisture as well as strong
shear for more surface-based storms which will have a good potential
for some severe.
The rain potential lingers into Thursday if the cold front slows
enough to not make it thru until this day.
Friday should be a dry day, finally, but it appears only briefly
until yet another storm system approaches from the west in time for
the following weekend.
Otherwise, the longwave RIDGE setup will ensure that temps remain at
or above average throughout the period.
TES
&&
.AVIATION... (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1104 AM CDT Sat Apr 23 2016
Surface ridge extending from the Great Lakes region southwest
into eastern MO will shift eastward this period. The low level
cloudiness over eastern IA into northeast MO should remain north
of UIN this afternoon. The stratus cloudiness across southeast IL
should gradually dissipate this afternoon with daytime heating,
mixing and drying and remain east of the St Louis metro area.
There may be a few diurnal cumulus clouds at the taf sites this
afternoon. There will be a little high level cloudiness late
tonight and Sunday morning. Southeasterly surface winds should
strengthen at UIN and COU through the forecast period as the
surface pressure gradient gradually tightens, becoming more
southerly on Sunday. Light northeast wind in the St Louis metro
area will also strengthen as well through the period, veering
around to a southeast direction by early this evening, then
southerly Sunday morning. There will be some LLWS conditions in
UIN and COU very late tonight and early Sunday morning as a
southwesterly low level jet translates eastward into northwest MO
with both speed and directional shear in the lowest 1000 feet.
Specifics for KSTL: Stratus clouds across southeast IL should
gradually dissipate this afternoon and remain east-southeast of
STL. Few diurnal cumulus clouds may develop this afternoon due to
daytime heating, then dissipate early this evening. There will be
some high level cloudiness late tonight and Sunday. Light
northeast wind will increase in speed to 8-10 kts by late this
afternoon or early this evening as it veers around to a southeast
direction. The surface wind will become southerly Sunday morning
and possibly gusty Sunday afternoon.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1242 PM CDT SUN APR 24 2016
.UPDATE...
ISSUED AT 1235 PM CDT SUN APR 24 2016
PARAMETERS ARE STILL COMING TOGETHER FOR A THREAT OF SEVERE THIS
AFTERNOON. AREA OF MID AND UPPER 50S DEW POINTS WERE BEGINNING TO
SURGE NORTH INTO WESTERN SECTIONS OF EASTERN NEBRASKA AS OF
NOON...JUST EAST OF DRYLINE IN CENTRAL NEBRASKA. SCATTERED SHOWERS
HAVE PERSISTED IN MID LEVEL WARM ADVECTION THERE...BUT CLEARING TO
THE EAST WAS NOTED ON VISIBLE SATELLITE LOOPS. THIS WAS ALLOWING
TEMPERATURES TO CLIMB INTO THE 70S. WHERE MOISTURE AND WARMING WERE
COINCIDENT IN CENTRAL KANSAS...SURFACE-BASED CAPES WERE ALREADY
TOPPING 1000 J/KG. AND WITH CONTINUED WARMING/MOISTENING...EXPECT AT
LEAST 1500 J/KG JUST AHEAD OF DRYLINE LATER THIS AFTERNOON IN
EASTERN NEBRASKA. BULK SHEAR WAS INCREASING AS EXPECTED AS
WELL...WITH 0-6KM VECTORS SOUTHWEST AT 30KT AS OF NOON. A
CONSENSUS OF HI-RES CONVECTION-ALLOWING MODELS SUGGESTS
INITIATION WILL OCCUR SOMETIME NEAR OR JUST AFTER 21Z...LIKELY
ALONG A WAYNE TO JUST WEST OF LINCOLN LINE AS PER EXPERIMENTAL
HRRR OUTPUT. GIVEN EXPECTED INSTABILITY AND SHEAR VECTORS BECOMING
MORE NORMAL TO LINE OF CONVECTION...SUPERCELL STRUCTURES ARE
LIKELY WITH ATTENDANT LARGE HAIL AND DAMAGING WIND THREAT. THERE
IS ALSO A SMALL TORNADO RISK...ESPECIALLY IN SOUTHEAST NEBRASKA AT
LATE AFTERNOON WHERE AXIS OF HIGHER HELICITY NOSES IN FROM THE
SOUTH.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 315 AM CDT SUN APR 24 2016
THE POTENTIAL FOR SEVERE STORMS TODAY IS THE MAIN FCST CONCERN.
CLOSED LOW AT 500 MB WAS NEAR THE UT/WY/CO BORDER AREA AT 00Z WITH
12 HOUR HEIGHT FALLS OF UP TO AROUND 80 METERS JUST AHEAD OF THE
CIRCULATION CENTER. THERE WAS A JET SEGMENT OF AROUND 70 KTS AT
300 MB NEAR THE UT/CO BORDER. AT 700 MB...THERMAL RIDGE AXIS
STRETCHED FROM SWRN NM UP INTO SERN MT. MOIST AXIS AT 850 MB
EXTENDED FROM TX INTO THE DKTS. WATER VAPOR STLT IMAGERY EARLY
THIS MORNING SHOWED THE MID TROPOSPHERIC LOW HAD PROGRESSED INTO
CENTRAL WY. SFC ANLYS AT 08Z HAD A LOW PRES CENTER OVER WRN SD.
A WMFNT EXTENDED E/NE FROM THE LOW INTO MN AND A CDFNT EXTENDED
S/SW INTO NERN NM. DEWPOINTS AHEAD OF THE CDFNT WERE IN THE UPPER
40S AND LOWER 50S.
TODAY...CURRENT SHOWERS AND TSTMS TO OUR WEST SHOULD MOVE INTO
THE AREA THIS MORNING BUT IT APPEARS THESE WILL STAY BELOW SVR
LIMITS. RECENT RUNS OF THE RAP AND HRRR MODELS DEPICT VIGOROUS
STORM DEVELOPMENT IN OUR AREA THIS AFTN. SFC-500 METER MIXED
LAYER CAPE VALUES COULD REACH AROUND 2000 J/KG BY MID AFTN IN OUR
WRN ZONES...BASED ON DEWPOINTS RISING TO THE MID/UPPER 50S. THE
STRONGEST STORMS SHOULD FORM THERE AND THEN DVLP EWD. ZERO TO 6 KM
SHEAR VALUES OF 35-45 KTS SHOULD BE ENOUGH FOR SOME SUPERCELLS...
WITH HAIL THE MOST LIKELY HAZARD. EXPERIMENTAL HRRR AND MANY OTHER
CONVECTION ALLOWING MODELS SHOW SIMILAR RESULTS. LOOK FOR HIGHS 75
TO 80.
STORMS SHOULD CONTINUE TO DVLP EWD AND MAINLY BE OUT OF THE AREA
BY 06Z TNGT. SOME SMALL CHANCE OF SHOWERS MAY LINGER INTO THE
EARLY MORNING HOURS...MAINLY NEAR THE SD BORDER. SFC LOW SHOULD BE
JUST NW OF KSUX BY 12Z MON...THEN THAT WILL MOVE TO NEAR THE
WI/IA/MN BORDER AREA BY 00Z TUE. NW SFC WINDS SHOULD PULL COOLER
AIR INTO NERN NE FOR MON...BUT COOLING WILL BE LESS FOR SERN NE
AND SWRN IA. THERE COULD BE SOME LGT PCPN IN OUR NRN COUNTIES MON
BUT FOR NOW KEPT MON INTO MON NGT DRY. OUR NEXT CHANCE OF SHOWERS
AND TSTMS WILL BE ON TUE...AS LOW PRES INTENSIFIES OVER ERN CO AND
WRN KS. LOCATION OF A NWD LIFTING WMFNT WILL BE CRITICAL...BUT IT
DOES APPEAR THERE WILL BE ENOUGH INSTABILITY IN SERN NE FOR SOME
STG TO SVR STORMS TUE AFTN AND EVENING.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 315 AM CDT SUN APR 24 2016
OVERALL THIS PERIOD LOOKS RATHER ACTIVE. DIFFLUENT FLOW SHOULD BE
IN PLACE OVER THE AREA AT THE START OF THIS PERIOD...AHEAD OF A
CLOSED LOW IN SRN WY. WED COULD ALSO BE AN ACTIVE DAY WITH STORMS
BUT WITH FAIRLY WIDESPREAD CLOUDS AND PCPN SVR POTENTIAL IS NOT
CLEAR. IT DOES APPEAR THAT WE WILL DRY OUT THU INTO THU NGT...BUT
RAIN CHANCES SHOULD RETURN FRI AND PROBABLY LAST INTO THE WEEKEND.
&&
.AVIATION...(18Z TAFS FOR KOMA...KLNK...KOFK THROUGH 18Z MONDAY)
ISSUED AT 1235 PM CDT SUN APR 24 2016
GENERALLY VFR CONDITIONS ARE FORECAST OUTSIDE OF SHOWERS AND
THUNDERSTORMS EXPECTED TO OVERSPREAD TAF SITES THIS AFTERNOON INTO
THE EVENING. AREA OF STORMS JUST SOUTHWEST OF KOFK AS OF NOON WILL
MOVE OVER THAT SITE...AND WILL LIKELY MOVE OFF TO THE NORTHEAST BY
20Z. LINE OF STORMS IS EXPECTED TO FIRE EAST OF KOFK AND WEST OF
KLNK BY 21Z OR SO...AND MOVE EAST ACROSS KLNK AND KOMA TAF SITES
BETWEEN 21Z AND 03Z. ATTENDANT IFR VSBYS AND POTENTIAL CIGS WILL
ACCOMPANY THUNDERSTORMS. LARGE HAIL IS ALSO A POSSIBILITY WITH ANY
STORMS BUT WAS NOT MENTIONED IN TAF AT THE MOMENT. STORMS WILL
MOVE EAST OF EASTERN NEBRASKA TAF SITES AFTER 03Z...WITH LINGERING
SHOWERS POSSIBLE OVERNIGHT. OTHERWISE VFR CIGS AND WINDS BECOMING
SOUTHWEST OR WEST BY 12Z CAN BE EXPECTED.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...DERGAN
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
321 PM PDT SUN APR 24 2016
.SYNOPSIS...UNSETTLED WEATHER WILL SETTLE IN OVER THE AREA FOR THE
NEXT SEVERAL DAYS AS A SERIES OF SPRING STORM SYSTEMS MOVE THROUGH
THE REGION. THE FIRST SYSTEM TONIGHT WILL BRING INCREASING WINDS AND
CHANCES FOR PRECIPITATION TO PARTS OF THE AREA THAT WILL CONTINUE
THROUGH MONDAY EVENING. A BRIEF BREAK IS EXPECTED TUESDAY BEFORE
ANOTHER STORM SYSTEM MOVES IN MIDWEEK WITH RENEWED SHOWER CHANCES
AND MORE GUSTY WINDS.
&&
.DISCUSSION...ENERGY FROM THE NEXT PACIFIC SYSTEM IS BEGINNING TO
MOVE INTO THE AREA WITH GUSTY SOUTHERLY WINDS DEVELOPING ACROSS MUCH
OF THE REGION THIS AFTERNOON. MID AND HIGH CLOUDS HAVE EXPANDED TO
ACROSS MOST OF THE AREA AS WELL. A FEW LIGHTNING STRIKES WERE NOTED
IN THE SIERRA BUT JUST NORTH OF OUR AREA OF RESPONSIBILITY FOR THE
MOMENT. THE SYSTEM WILL MOVE INTO THE AREA TONIGHT AND MONDAY WITH A
BROAD CLOSED LOW DEVELOPING OVER THE SOUTHERN GREAT BASIN EARLY
MONDAY AND THEN MOVE EAST OF THE AREA MONDAY NIGHT INTO TUESDAY.
STRONG WINDS WILL DEVELOP OVER THE WESTERN PORTIONS OF SAN
BERNARDINO COUNTY LATER THIS AFTERNOON AND CONTINUE THROUGH MUCH OF
MONDAY WHERE A WIND ADVISORY IS IN EFFECT. A COLD FRONT WILL MOVE
INTO THE NORTHWEST CWA MONDAY MORNING AND GUSTY NORTHWEST WINDS ARE
EXPECTED TO DEVELOP BEHIND THE FRONT OVER ESMERALDA AND CENTRAL NYE
COUNTIES. A WIND ADVISORY HAS BEEN ISSUED FOR THESE AREAS FOR
MONDAY. STRONG WINDS ACROSS THE MOJAVE DESERT WILL SPREAD EASTWARD
ACROSS SOUTHERN SAN BERNARDINO INTO SOUTHERN MOHAVE COUNTIES MONDAY
AFTERNOON AND CONTINUE INTO THE EVENING. A WIND ADVISORY HAS BEEN
ISSUED FOR THESE AREAS FOR MONDAY AFTERNOON. WINDS WILL DECREASE
AREA WIDE BY MIDNIGHT MONDAY WITH LIGHTER WINDS EXPECTED TUESDAY
BEHIND THE SYSTEM.
OTHER THAN WIND, SHOWERS AND ISOLATED THUNDERSTORMS WILL
DEVELOP OVER THE SIERRA AND EASTWARD ACROSS THE SOUTHERN GREAT BASIN
THIS EVENING WITH SHOWERS CONTINUING THROUGH THE NIGHT. MOST AREAS
NORTH OF I-40 WILL HAVE A CHANCE OF RAIN AND MOUNTAIN SNOW MONDAY
WITH SHOWER CHANCES DECREASING MONDAY NIGHT. SNOW IS EXPECTED IN THE
HIGHER ELEVATION ABOVE 6500 FEET WITH 1-3 INCHES POSSIBLE IN LINCOLN
COUNTY THROUGH MID DAY MONDAY. DECIDED AGAINST A WINTER WEATHER
ADVISORY FOR NOW BASED ON EXPECTED ACCUMULATIONS AND RECENT WARM
CONDITIONS.
SHORTWAVE RIDGING ON TUESDAY QUICKLY GIVES WAY TO THE NEXT SYSTEM
MOVING INTO THE AREA EARLY WEDNESDAY. THIS ONE DEVELOPS FURTHER ONCE
IT MOVES OVER THE SOUTHWEST AND ADDITIONAL SHOWER CHANCES ARE
EXPECTED. STRONG WINDS ARE AGAIN FORECAST TO DEVELOP OVER THE
WESTERN MOJAVE DESERT WEDNESDAY AND HEADLINES MAY BE NECESSARY.
DEPENDING ON THE EVENTUAL TRACK OF THE SYSTEM, MOST AREAS COULD SEE
AT LEAST A SLIGHT CHANCE OF SHOWERS WEDNESDAY/THURSDAY. MODELS ARE
IN PRETTY GOOD AGREEMENT THAT IMPACTS FROM THIS SYSTEM WILL BE OVER
BY EARLY FRIDAY.
A BREAK FROM ACTIVE WEATHER IS POSSIBLE FRIDAY/SATURDAY BUT ENSEMBLE
SPREAD IS HIGH AND MODEL SOLUTIONS ARE ALL OVER THE PLACE FOR NEXT
WEEKEND. FOR WHAT THEY ARE WORTH, THE 12Z MODELS AGREE ON A MOSTLY
DRY...WINDY INSIDE SLIDER. BUT WE`LL SEE.
&&
.AVIATION...FOR MCCARRAN...CLOUDS WILL CONTINUE TO LOWER OVERNIGHT
WITH SCT-BROKEN SKIES AROUND 10KFT EXPECTED WITH PERIODS OF
OVERCAST. STRONGER SOUTHWEST WINDS ARRIVE LATE THIS AFTERNOON/EARLY
EVENING IN THE 10-15 KNOT RANGE. WINDS WILL CONTINUE TO FAVOR WEST
AND SOUTHWEST DIRECTIONS THROUGH MONDAY WITH SPEEDS OF 15-25 KNOTS
AND GUSTS AROUND 30 KNOTS. CANNOT RULE OUT SOME LIGHT SHOWERS AROUND
THE VALLEY TONIGHT AND MONDAY, BUT CONFIDENCE IS LOW THAT THEY WILL
MOVE OVER THE AIRFIELD. MOUNTAIN OBSCURATIONS AND MECHANICAL
TURBULENCE ARE POSSIBLE THROUGH MONDAY.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...CLOUD BASES WILL LOWER BECOMING SCT-BKN AROUND 10KFT,
ESPECIALLY NORTH OF INTERSTATE 40. STRONG AND GUSTY SOUTHWEST WINDS
WILL IMPACT TAF SITES NEAR KDAG AND KNXP THROUGH THE PERIOD WITH
GUSTS OVER 35KTS LIKELY AND AREAS OF BLOWING DUST. SHOWERS, MOUNTAIN
OBSCURATIONS AND MECHANICAL TURBULENCE ARE POSSIBLE THROUGH MONDAY
AROUND KBIH, KVGT, AND KHND. &&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION IS NOT
ANTICIPATED THIS WEEKEND. HOWEVER, SPOTTERS SHOULD REPORT ANY
SIGNIFICANT WEATHER ACCORDING TO STANDARD OPERATING PROCEDURES.
&&
$$
DISCUSSION...SALMEN
AVIATION...PADDOCK
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
[top]
Area Forecast Discussion
National Weather Service Reno NV
231 PM PDT SUN APR 24 2016
.SYNOPSIS...
Low pressure will move through western Nevada tonight and Monday.
Light snow is expected near the Oregon Border tonight while most
locations see a few showers and brisk northwest winds. After a
break Tuesday, unsettled weather returns for Wednesday and
Thursday. A warming trend with dry weather is looking more likely
for next weekend.
&&
.SHORT TERM...
Scattered showers have developed across Northeast California and
Western NV this afternoon and will continue into the evening. With
the cloud cover, instability has not been as great as anticipated,
but a few thunderstorms remain possible through sunset. Localized
rainfall amounts up to 1/3" are possible in the heaviest showers.
Snow levels are running around 6000 feet into this evening, but
will drop as the cold upper low moves in.
Overnight and into Monday, have made a few adjustments based on
latest trends and model forecasts. The main adjustments were to
increase the precip chances north of a Susanville-Lovelock line
and increase winds a bit more Monday afternoon. With the upper low
diving into Western NV tonight, the GFS, HRRR and EC all show an
area of deformation setting up from Austin, NV to Cedarville, CA.
QPF amounts are averaging 1/4" to 1/2" in this band. Snow levels
are expected to drop to near 4000-4500 feet. Issued a winter
weather advisory for light snow amounts near the Oregon Border
where it is more likely to stick to roads as they will be in the
cold air longer.
Monday morning that band dissipates as the upper low moves into
southern NV. The low is moving through a little faster and will
take the upper cold pool with it resulting in more stabilization.
Still expect some showers in the afternoon, but they are looking
more likely to be confined to areas south of highway 50. It still
looks quite cool, and a brisk NW wind of 15-25 mph with higher
gusts will make it feel colder. With these winds aligned with
Pyramid Lake, issued a Lake Wind Advisory there.
Monday night and Tuesday will see quiet weather under a short wave
ridge. Then the next upper low is expected to arrive Tuesday night
into Wednesday. This one will not be quite as cold, although it
will have some moisture. Forcing also does not look overly strong,
so at this point we are expecting showers again with a few
thunderstorms possible. Wallmann
.LONG TERM...Thursday through Sunday...
Active weather continues late next week as mean upper level
troughing remains fixed over the Western United States. Low
pressure that will move into the region Wednesday will slowly exit
into the Inter-Mountain West Friday night into Saturday. Snow
levels remain around 6000-7000 feet through Friday before rising
7000-8000 feet over the weekend. Kept mention of thunderstorms for
Thursday afternoon since sufficient instability remains.
Models have changed a little from previous runs for Saturday and
Sunday. Previously, deterministic runs were showing another low
dropping into the backside of the trough impacting Western Nevada
and the Sierra. Now, deterministic runs and ensembles are favoring
a more eastward track with low pressure pushing through Eastern
Nevada and Utah. As a result, have begun to back off of
precipitation chances over the weekend. Correspondingly, have
increased daily highs for the weekend as well with temperatures
approaching 70 degrees for Western Nevada Valleys. Boyd
&&
.AVIATION...
Low pressure will continue to impact the region this afternoon
into Monday at all terminals. Expect periods of IFR/MVFR in the
Sierra by Monday morning with periods of snow. MVFR conditions
will be possible for Sierra Front with snow levels dragging down
to around 4500 feet. It is possible that there could be periods of
IFR and light rain/snow mix at KRNO and KCXP Monday morning as
well. However, surface temperatures for Sierra Front terminals
will be too warm to allow for much/any snow to stick on the
tarmac.
Winds will increase with gusts generally up to 30 knots for
Sierra Front terminals while winds at KTVL/KTRK being lighter due
to precipitation influences. KMMH may see a few intermittent gusts
up to 40 knots Monday. Boyd/Hoon
&&
.REV Watches/Warnings/Advisories...
NV...Lake Wind Advisory from 6 AM to 8 PM PDT Monday for Pyramid Lake
in NVZ004.
Winter Weather Advisory from 8 PM this evening to 8 AM PDT
Monday NVZ005.
CA...Winter Weather Advisory from 8 PM this evening to 8 AM PDT
Monday CAZ070.
&&
$$
For more information from the National Weather Service visit...
http://weather.gov/reno
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1218 PM CDT SUN APR 24 2016
.UPDATE...
ISSUED AT 1218 PM CDT SUN APR 24 2016
CURRENT FORECAST IS ON TRACK WITH SEVERAL BANDS OF SHOWERS AND
THUNDERSTORMS ROTATING AROUND A VERTICALLY STACKED CLOSED LOW
CIRCULATING IN SOUTHWEST SOUTH DAKOTA. THE PREVIOUS FORECAST AND
LATEST HRRR BOTH HAVE HAD THE RIGHT IDEA WITH THE CURRENT POP
TRENDS. THUS VERY LITTLE IF ANY ADJUSTMENTS NEEDED AT THIS TIME.
WINDS STILL STRONGEST IN NORTHERN NORTH DAKOTA WITH RUGBY
SUSTAINED AT 30 MPH. HOWEVER AREAL COVERAGE IS LIMITED AND TRENDS
WITH THESE SUSTAINED WINDS WILL FALL DURING THE AFTERNOON. THUS
WILL CONTINUE TO MESSAGE THE GUSTY WINDS VIA THE HAZARDOUS
WEATHER OUTLOOK THIS AFTERNOON.
INTERESTING THE 12Z NAM/GFS/SREF ALL DEVELOP A CLOSED MID LEVEL
CIRCULATION/700MB LOW...LATE SUNDAY NIGHT THROUGH MONDAY. THIS LOW
MOVES FROM EAST TO WEST WITHIN THE DEFORMATION ZONE THAT REMAINS
STATIONARY ACROSS CENTRAL AND SOUTHERN NORTH DAKOTA. THE NET
RESULT WILL LIKELY BE A WET MONDAY DEVELOPING FROM EAST TO WEST.
MORE ON THIS IN THE AFTERNOON DISCUSSION.
UPDATE ISSUED AT 1056 AM CDT SUN APR 24 2016
QUICK UPDATE FOR CONVECTION DEVELOPING NORTH OF HIGHWAY 2. HAVE
ADDED IN SCATTERED THUNDERSTORMS IN THIS AREA TAPERING TO ISOLATED
NEAR THE CANADIAN BORDER UNTIL EARLY AFTERNOON. UPDATES
FORTHCOMING.
UPDATE ISSUED AT 954 AM CDT SUN APR 24 2016
LATEST WATER VAPOR IMAGERY LOOP SHOWS THE DRY SLOT FROM PREVIOUS
DISCUSSION HAS WRAPPED TOTALLY AROUND THE VERTICALLY STACKED
MID/UPPER LOW. OCCLUDED SYSTEM NOW CIRCULATING IN SOUTHWEST SOUTH
DAKOTA WILL CONTINUE TO SHIFT EAST TODAY...RIDING ALONG THE SOUTH
DAKOTA/NEBRASKA BORDER. DEFORMATION ZONE EVIDENT ACROSS SOUTHERN
NORTH DAKOTA. RADAR SHOWS ECHOES FILLING IN ACROSS THIS AREA...AND
CURRENT POPS ON TRACK FROM PREVIOUS UPDATE. DID ADJUST WINDS A BIT
HIGHER TODAY USING A BLEND OF THE MAV/MET GUIDANCE GIVEN CURRENT
OBSERVATIONS. AFTER COORDINATING WITH GRAND FORKS...WILL HOLD OFF
ON ANY WIND ADVISORY...AS MINIMAL AREAL COVERAGE AND OVERALL
LENGTH OF TIME MEETING SUSTAINED 30 MPH IS MARGINAL. ALSO COORDINATED
WITH GRAND FORKS TO INCREASE POPS TONIGHT AS STRATIFORM PRECIP
SHIELD ON THE NORTHWEST SIDE OF THE STACKED LOW IS FORECAST TO
ENVELOP MOST OF CENTRAL/SOUTHERN NORTH DAKOTA.
UPDATE ISSUED AT 649 AM CDT SUN APR 24 2016
THE 06-10 UTC HIGH RESOLUTION SUITES HAVE CONSISTENTLY SHIFTED
THE AXIS OF HEAVIEST RAINFALL FURTHER NORTHERN INTO THE HIGHWAY
200 AND US HIGHWAY 2 CORRIDORS. THIS IS CONSISTENT WITH A DRY SLOT
EVIDENT ON SATELLITE THROUGH 1130 UTC ACROSS WESTERN SOUTH DAKOTA
AND NEBRASKA THAT WILL PROPAGATE NORTH INTO SOUTHWEST AND SOUTH
CENTRAL NORTH DAKOTA THROUGH THE DAY. THUS SHIFTED THE GREATEST
POPS AND RAINFALL TOTALS FURTHER NORTH IN LINE WITH THE
AFOREMENTIONED GUIDANCE SUITES. MAINTAINED THE MENTION OF THUNDER
SOUTH OF US HIGHWAY 2 WITH MODEST ELEVATED INSTABILITY WITH STRONG
DEEP LAYER SHEAR.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 318 AM CDT SUN APR 24 2016
WIDESPREAD RAINFALL IS EXPECTED TODAY AND TONIGHT AS THE NORTHERN
PLAINS LOW DEEPENS AND LOW-LEVEL FRONTOGENESIS INTENSIFIES.
ISOLATED THUNDERSTORMS ARE POSSIBLE THIS MORNING WITH AN UNSTABLE
ELEVATED MOIST LAYER.
HIGH-RES MODELS CONTINUE TO DELAY THE ONSET OF PRECIPITATION.
CURRENT RADAR ANALYSIS INDICATED ZERO PRECIPITATION ACROSS WESTERN
AND CENTRAL NORTH DAKOTA AS OF 4 AM. THIS IS EXPECTED TO CHANGE
LATER THIS MORNING AS UPPER LEVEL SUPPORT AND INCREASED MOISTURE
ADVECTION MOVE INTO THE AREA. THE AXIS OF HEAVIEST RAINFALL STILL
APPEARS TO LINE UP BETWEEN I94 AND HIGHWAY 200...WHERE 1 TO 1.5
INCHES OF RAIN IS EXPECTED.
ACROSS FAR NORTHERN NORTH DAKOTA THERE MAY BE A BRIEF TRANSITION
FROM RAIN TO FREEZING RAIN OR SNOW AS TEMPERATURES FALL BELOW
CRITICAL THRESHOLDS.
GUSTY NORTHEAST WINDS WILL CONTINUE TODAY. THE STRONGEST WINDS
ARE FORECAST ALONG AND NORTH OF HIGHWAY 2...WITH THE TURTLE
MOUNTAINS PINPOINTED FOR THE HIGHEST SUSTAINED WINDS OF AROUND 30
MPH AND GUSTS TO 45 MPH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 318 AM CDT SUN APR 24 2016
SEVERAL WAVES WILL EJECT ACROSS THE PLAINS THIS WEEK. THIS WILL
LEAD TO RAIN CHANCES THROUGH THURSDAY. MODELS ARE FAIRLY
CONSISTENT IN TIMING AND PLACEMENT OF PRECIPITATION. AT THIS TIME
IT APPEARS WESTERN AND SOUTHERN NORTH DAKOTA HAVE THE HIGHEST
CHANCES OF SEEING RAIN MONDAY THROUGH THURSDAY.
WITH PERSISTENT EAST/NORTHEAST WINDS AND STUBBORN CLOUD
COVER...TEMPERATURES WILL REMAIN COOL WITH READINGS DURING THE DAY
IN THE 40S AND LOW 50S AND OVERNIGHT LOWS IN THE 30S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1218 PM CDT SUN APR 24 2016
IFR/LIFR CONDITIONS WILL CONTINUE THROUGH AT LEAST MIDDAY MONDAY
ACROSS SOUTHWEST AND SOUTH CENTRAL ND. IN NORTHERN AREAS...FROM
KISN TO KMOT...MVFR CONDITIONS MAY PREVAIL. RAIN IS FORECAST FOR
MOST OF WESTERN AND CENTRAL ND THROUGH MONDAY...BUT THE CHANCE OF
THUNDERSTORMS WILL DIMINISH BY 00 UTC THIS EVENING. SOME SNOW IS
POSSIBLE LATE TONIGHT AND MONDAY MORNING IN THE WEST AND NORTH.
FINALLY...EAST-NORTHEAST WINDS WHICH ARE GUSTING UP TO 35 KT AT
MIDDAY WILL GRADUALLY DECREASE BY TONIGHT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...CJS
AREA FORECAST DISCUSSION
NWS PORTLAND OR
222 PM PDT SUN APR 24 2016
.SYNOPSIS...UNSETTLED WEATHER IN PLACE THIS AFTERNOON WITH A MIX OF
CLOUDS AND SUNBREAKS...PLENTY OF SHOWERS...SOME WITH SMALL HAIL
AND/OR A STRAY RUMBLE OF THUNDER. COOL AIR ALOFT HAS ALSO LOWERED THE
SNOW LEVEL TO NEAR THE CASCADE PASSES...WHERE A COUPLE MORE INCHES
OF SNOW ARE POSSIBLE THROUGH MONDAY. SNOW LEVELS WILL DROP A LITTLE
FURTHER TONIGHT AS THE BULK OF THE COLD AIR ALOFT SWINGS THROUGH THE
REGION. HIGHER PRESSURE WILL BUILD OFFSHORE FOR LESS SHOWER COVERAGE
MONDAY THEN DRIER WEATHER MONDAY NIGHT INTO TUESDAY. NEXT CHANCE FOR
SHOWERS COMES TUE NIGHT AND WED AS A SPLITTING SYSTEM APPROACHES THE
WEST COAST. THE MODELS ARE TRENDING DRIER FOR LATER NEXT WEEK AND
NEXT WEEKEND AS A FLAT UPPER LEVEL RIDGE OF HIGH PRESSURE DEVELOPS
OFFSHORE.
&&
.SHORT TERM...TONIGHT THROUGH WEDNESDAY...CLASSIC SPRING UNSETTLED
WEATHER PATTERN IN PLACE TODAY...WITH A COLD POOL ALOFT NEAR THE
OREGON COAST. WITHIN THE CORE OF THE COLD POOL...20Z RAP ANALYSIS
STILL SHOWS 500 MB TEMPS AS LOW AS -33 DEG C...PLENTY COLD TO SUPPORT
CONVECTION AND VERY ISOLATED THUNDERSTORMS. SHOWERS ARE FAIRLY
WIDESPREAD ACROSS SW WA/NW OR THIS AFTERNOON...WITH A FEW OF THE
STRONGER ONES PRODUCING PEA-SIZED HAIL AND/OR A LIGHTNING STRIKE OR
TWO. AS EXPECTED THE CELLS HAVE GENERALLY BEEN PULSE-TYPE WITH LITTLE
TO NO ORGANIZATION. MOST ARE ONLY LASTING THE FIRST UPDRAFT CYCLE
BEFORE COLLAPSING BACK DOWN ON THEMSELVES. THERE DOES APPEAR TO BE A
LOOSELY ORGANIZED LINE OF CONVECTION FROM HILLSBORO TO EUGENE...
MARCHING SLOWLY EASTWARD ACROSS THE WILLAMETTE VALLEY ALONG A WEAK
FRONTAL BOUNDARY ALOFT. WILL CONTINUE TO MONITOR THIS AREA...BUT IT
IS DOUBTFUL IT WILL DO MUCH OTHER THAN PRODUCE A COUPLE AREAS OF
SMALL HAIL AND A COUPLE STRAY LIGHTNING STRIKES. OTHERWISE EXPECT
SIMILAR MAINLY PULSE-TYPE SHOWERS TO CONTINUE UNTIL SUNSET BEFORE
DECREASING IN COVERAGE WITH THE LOSS OF SOLAR HEATING.
TEMPERATURES TODAY STAND IN SHARP CONTRAST TO WHAT THE REGION HAS
FELT FOR MUCH OF THE MONTH OF APRIL...WE MAY ACTUALLY END UP BELOW
NORMAL FOR THE DAY AS HIGHS STRUGGLE TO GET OUT OF THE 50S IN THE
LOWLANDS. SNOW LEVELS ARE DOWN NEAR THE CASCADE PASSES...BUT MOST OF
THE SNOW SEEMS TO BE MELTING EITHER ON CONTACT WITH THE ROADS OR
SHORTLY AFTERWARDS. WITHOUT THE FAIRLY STRONG LATE APRIL SUNSHINE...
SNOW SHOULD HAVE A LITTLE EASIER TIME ACCUMULATING ABOVE 3500 FT
TONIGHT. HEAVIER SNOW SHOWERS COULD PRODUCE A QUICK 1-2 INCH DUSTING
AT TIMES...BUT OTHERWISE SNOW AMOUNTS SHOULD BE FAIRLY LIGHT.
12Z GFS SHOWS THE CORE OF THE UPPER LOW OPENING UP INTO AN ENLONGATED
TROUGH TONIGHT AND MONDAY...MAKING VERY LITTLE INLAND PROGRESS.
REMNANT COOL AIR ALOFT WILL LIKELY TRIGGER A FEW SHOWERS MONDAY...
FAVORING THE HIGHER TERRAIN. 12Z NAM/GFS SOUNDINGS SUGGEST WARMER
AIR WILL ALREADY BE MOVING IN ALOFT BY AFTERNOON...KEEPING ANY
CONVECTION SHALLOWER THAN IT HAS BEEN THE PAST FEW DAYS. BY MONDAY
NIGHT UPPER LEVEL RIDGING WILL PROVIDE ENOUGH SUBSIDENCE TO BRING AN
END TO THE SHOWER ACTIVITY...YIELDING A MAINLY DRY AND SEASONABLE
LATE APRIL DAY TUESDAY.
MODELS SHOW GOOD AGREEMENT NOW THAT THE STRONG UPPER LOW DEVELOPING
SOUTH OF THE ALEUTIANS WILL REPLACE THE CURRENT GULF OF ALASKA
LOW...WHILE SENDING A SECONDARY UPPER TROUGH AND COLD FRONT TOWARD
THE U.S. WEST COAST. MODELS HAVE BEEN TRENDING TOWARD SPLITTING THIS
SYSTEM AS IT APPROACHES THE COAST...WITH A SIGNIFICANT AMOUNT OF ITS
ENERGY HEADING SOUTH TOWARD CALIFORNIA. STILL LOOKS LIKE IT WILL HOLD
TOGETHER ENOUGH TO BRING SOME RAIN TO THE DISTRICT TUE NIGHT/WED...
THOUGH AMOUNTS LOOK LIGHT. IMPACTS ARE EXPECTED TO BE MINIMAL IN THE
CASCADES...PERHAPS A LITTLE DUSTING UP TO 2 INCHES ABOVE PASS
LEVEL. WEAGLE
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY. A FEW RESIDUAL SHOWERS
MAY CONTINUE IN THE WEAKLY ONSHORE FLOW ALOFT WEDNESDAY NIGHT...
PARTICULARLY IN THE CASCADES SOUTH OF MT HOOD...BEFORE COMING TO AN
END BY EARLY SATURDAY. MEANWHILE...AN UPPER LEVEL RIDGE OVER THE
NORTHEAST PACIFIC STRENGTHENS AND BUILDS INTO THE PACIFIC NORTHWEST.
A PASSING SHORTWAVE MAY BRING SOME LIGHT SHOWERS TO THE NORTHERN
ZONES ON FRIDAY...BUT OTHERWISE A GENERALLY DRY END OF THE WEEK INTO
THE WEEKEND. HIGH TEMPERATURES GRADUALLY WARM AT THE END OF THE
WEEK...AND CLIMB A FEW DEGREES ABOVE SEASONAL NORMS BY NEXT
WEEKEND. CULLEN
&&
.AVIATION...AN UNSTABLE AIR MASS WILL CONTINUE TO BRING SCATTERED
SHOWERS TO THE FORECAST AREA TODAY AND TONIGHT. EXPECT PRIMARILY
VFR CONDITIONS BUT ISOLATED HEAVY SHOWERS OR THUNDERSTORMS MAY
BRING BRIEF MVFR OR LOWER CONDITIONS. SMALL HAIL CAN ALSO BE
EXPECTED WITH SHOWERS OR THUNDERSTORMS UNTIL ABOUT 02Z MON.
EXPECT PRIMARILY VFR THROUGH MON BUT THERE MAY BE LOCAL MVFR
CONDITIONS MON MORNING. THE CASCADES LIKELY REMAIN MOSTLY
OBSCURED TONIGHT UNDER LIGHT RAIN AND SNOW SHOWERS.
KPDX AND APPROACHES...PRIMARILY VFR CONDITIONS THROUGH TONIGHT.
WILL ALSO SEE A THREAT OF TSRA THRU 03Z MON WHICH MAY BRING BRIEF
MVFR CIGS AND VIS. /MH
&&
.MARINE...HIGH PRES TO THE WEST OF THE WATERS WILL MAINTAIN
NORTHWESTERLY WINDS ACROSS THE WATERS TONIGHT. WINDS ARE EXPECTED
TO REMAIN BELOW ADVISORY CRITERIA BUT STILL EXPECT GUSTS TO 20 KT
IN THE COOL UNSTABLE AIR MASS. WINDS EASE LATER TONIGHT AND MONDAY
AS THE HIGH PRES SHIFTS OVER THE WATERS. MODELS CONTINUE TO SHOW A
WEAKENING FRONT APPROACHING LATE TUE OR WED...BUT IMPACTS LOOK TO
REMAIN MINIMAL. WILL LIKELY SEE GUSTY NORTHERLY WINDS DEVELOP LATE
IN THE WEEK AS THERMAL LOW PRES BUILDS OVER NORTHERN CALIFORNIA
AND SOUTHERN OREGON. MODELS ALSO CONTINUE TO SHOW ANOTHER WEAK
FRONT MOVING ACROSS THE WATERS NEXT WEEKEND.
SEAS CURRENTLY AROUND 8 FT EARLY THIS MORNING...BUT WILL BUILD TO
AROUND 10 FT BY NOON TODAY AND CONTINUE THROUGH MONDAY. SEAS LOOK
TO FALL BELOW 10 FT MONDAY AFTERNOON AND REMAIN BELOW ADVISORY
CRITERIA THROUGH THURSDAY. /MH /64
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 3 PM PDT MONDAY
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR
OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 PM
THIS AFTERNOON TO 10 PM PDT THIS EVENING.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM TO
10 AM PDT MONDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS PORTLAND OR
1004 AM PDT SUN APR 24 2016
.SYNOPSIS...UNSETTLED WEATHER EXPECTED TODAY WITH A MIX OF CLOUDS AND
SUNBREAKS...PLENTY OF SHOWERS AND ISOLATED THUNDERSTORMS. COOL UPPER
LEVEL LOW IS MOVING ONSHORE INTO OREGON...DESTABILIZING THE AIR MASS
AND RESULTING IN THE UNSETTLED WEATHER. THE COOL AIR HAS ALSO DROPPED
THE SNOW LEVEL TO THE CASCADE PASSES...WHERE A COUPLE INCHES OF
ADDITIONAL SNOW ARE POSSIBLE THROUGH MONDAY. SNOW LEVELS WILL DROP A
LITTLE FURTHER TONIGHT AS THE BULK OF THE COLD AIR ALOFT SWINGS
THROUGH THE REGION. HIGHER PRESSURE WILL BUILD OFFSHORE FOR LESS
SHOWER COVERAGE MONDAY THEN DRIER WEATHER MONDAY NIGHT INTO TUESDAY.
NEXT CHANCE FOR SHOWERS COMES TUE NIGHT AND WED AS A SPLITTING SYSTEM
APPROACHES THE WEST COAST. THE MODELS ARE TRENDING DRIER FOR LATER
NEXT WEEK AND NEXT WEEKEND.
&&
.MORNING UPDATE...CLASSIC SPRING UNSETTLED WEATHER PATTERN SETTING UP
TODAY...WITH A COLD POOL ALOFT APPROACHING THE OREGON COAST. WITHIN
THE CORE OF THE COLD POOL...15Z RAP ANALYSIS SHOWS 500 MB TEMPS AS
LOW AS -33 DEG C...PLENTY COLD TO SUPPORT CONVECTION AND ISOLATED
THUNDERSTORMS. LATEST SATELLITE IMAGERY SHOWS A GOOD AMOUNT OF COLD
AIR CUMULUS OFFSHORE...WHILE LIGHTNING DETECTION SHOWS THE STRONGER
CELLS PRODUCING A HANDFUL OF LIGHTNING STRIKES. THE COLD POOL ALOFT
IS EXPECTED TO MODERATE SLIGHTLY WHILE APPROACHING THE COAST
TODAY...AND THE 12Z NAM NEVER QUITE BRINGS THE CORE OF THE COLD AIR
INLAND. ON THE OTHER HAND...VISIBLE SATELLITE IMAGERY SHOWS A FEW
SUNBREAKS WHICH WILL ENHANCE SURFACE HEATING AND INSTABILITY AS THE
DAY PROGRESSES. OVERALL IT APPEARS THE ENVIRONMENT ACROSS THE
FORECAST AREA WILL A FEW HEAVY SHOWERS...SOME SMALL HAIL...AND A
COUPLE THUNDERSTORMS TODAY. CELLS WILL PROBABLY HAVE DIFFICULTY
GETTING ORGANIZED GIVEN THE RATHER WEAK SHEAR PROFILE BELOW 500
MB...SO WE GENERALLY EXPECT PULSE-TYPE CELLS. CELLS COMING OFF THE
COAST RANGE WILL HAVE A LITTLE BETTER CHANCE AT ORGANIZATION DUE TO
TERRAIN-FORCED S-SW FLOW NEAR THE SURFACE VERSUS THE MORE WESTERLY
FLOW ABOVE 1 KM. WOULD NOT BE SURPRISED TO HEAR OF A COLD CORE FUNNEL
OR TWO THIS AFTERNOON...PATTERN RECOGNITION SUGGESTS MANY OF OUR
FUNNEL CLOUD CASES OCCUR WHEN A COLD CORE LOW IS MOVING ONSHORE. AS
USUAL...IT IS HIGHLY UNLIKELY ANY COLD-CORE FUNNELS WOULD TOUCH THE
GROUND AS A TORNADO SHOULD THEY DEVELOP.
OTHERWISE THE FORECAST LOOKS TO BE IN GOOD SHAPE...WARMED UP TEMPS
SLIGHTLY TODAY AND MONDAY AS WE SHOULD BE ABLE TO GET INTO THE UPPER
50S OR NEAR 60 WITH SUNBREAKS AND 850 MB TEMPS NEAR ZERO DEG C. SNOW
LEVELS APPEAR TO BE NEAR CASCADE PASS LEVEL PER ODOT WEBCAMS...MOST
OF THE SNOW SEEMS TO BE MELTING EITHER ON CONTACT WITH THE ROADS OR
SHORTLY AFTERWARDS. HEAVIER SNOW SHOWERS IN THE CASCADES COULD
PRODUCE A QUICK 1-2 INCH DUSTING AT TIMES...BUT OTHERWISE SNOW
AMOUNTS SHOULD BE FAIRLY LIGHT. WEAGLE
/PREV DISC ISSUED 321 AM PDT SUN APR 24 2016/
.SHORT TERM...A COLD FRONT MOVED THROUGH SOUTHWEST WASHINGTON AND
NORTHWEST OREGON OVERNIGHT. ONSHORE FLOW BEHIND THE FRONT WILL SPREAD
MORE SHOWERS ONSHORE TODAY. THE ASSOCIATED PARENT UPPER LOW IS TO
APPROACH THE COAST TODAY...THEN DIG SOUTH TOWARD THE GREAT BASIN
TONIGHT AND TUESDAY. THIS SHOULD KEEP DECENT SHOWER ACTIVITY OVER THE
FORECAST AREA TODAY...WITH SNOW LEVELS BELOW THE CASCADE PASSES.
THERE WILL LIKELY BE ACCUMULATING SNOW IN THE PASSES...BUT BELOW SNOW
ADVISORY CRITERIA.
THE COOLER AIR ALOFT SPREADING IN TODAY WITH THE UPPER LOW WILL
RESULT IN A CHANCE OF THUNDER...ESPECIALLY THIS AFTERNOON AND
EVENING. ANY THUNDERSTORMS THAT DO DEVELOP WILL HAVE SOME HAIL...
GUSTY WINDS...AND HEAVY SHOWERS WITH THEM. THE COOLER AIR WILL ALSO
KEEP HIGHS INLAND TODAY IN THE 55 TO 60 RANGE.
AS THE LOW DIGS SOUTH...SHOWER COVERAGE WILL DECREASE LATER TONIGHT
AND MONDAY...THOUGH THE SHOWERS WILL NOT END DUE TO BEING ON THE
CYCLONIC SIDE OF THE JET.
AN UPPER LEVEL RIDGE BRINGS DRYING TO THE AREA MONDAY NIGHT AND
TUESDAY. LOOK FOR SOME AREAS OF LOW CLOUDS AND PATCHY FOG DEVELOPING
LATER MONDAY NIGHT THROUGH TUESDAY MORNING...THEN BREAKING UP TUESDAY
AFTERNOON WITH INLAND TEMPS CLIMBING BACK INTO THE LOWER 60S.
TOLLESON
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
EXPECT INCREASING CLOUDS AGAIN TUESDAY NIGHT WITH THE NEXT FRONTAL
SYSTEM OFFSHORE AND APPROACHING THE COAST. FORECAST MODELS SUGGEST A
SPLITTING SYSTEM WITH THE MAJORITY OF THE ENERGY MOVING TO THE SOUTH
OF THE FORECAST AREA. AS A RESULT...HAVE INCREASED POPS OVER THE
SOUTHERN PORTIONS OF THE FORECAST AREA FOR LATE TUESDAY NIGHT THROUGH
WEDNESDAY TO CHANCE RANGE...TAPERING OFF TO SLIGHT CHANCE FOR THE
NORTHERN ZONES. THE GENERAL TREND IN THE MODEL GUIDANCE SUPPORTS THIS
UPPER LOW DEEPENING OVER THE GREAT BASIN OR FOUR CORNERS REGION FOR
THE SECOND HALF OF NEXT WEEK...WITH A WEAK RIDGE SETTING UP OVER THE
REGION. A FEW SHORTWAVES MAY ATTEMPT TO PASS OVER THE TOP OF THIS
RIDGE. FOR NOW...EXPECT THAT THE EXTENDED PERIOD WILL GENERALLY BE
MARKED BY MORE PERIODS OF DRY THAN WET BUT THE TIMING OF THE PERIODS
OF PRECIPITATION WILL LIKELY BE REFINED IN THE COMING DAYS. CULLEN
&&
.AVIATION...AN UNSTABLE AIR MASS WILL CONTINUE TO BRING SCATTERED
SHOWERS TO THE FORECAST AREA TODAY AND TONIGHT. EXPECT PRIMARILY
VFR CONDITIONS THIS AFTERNOON...BUT ONSHORE FLOW MAY KEEP A MIX
OF CIGS AT THE COAST. THE UNSTABLE AIR MASS WILL ALSO BRING A
THREAT OF TSRA AND ISOLATED MVFR OR IFR CONDITIONS ACROSS THE
REGION THROUGH THIS EVENING. WILL LIKELY SEE CIGS BECOME PRIMARILY
MVFR ALONG THE COAST LATE TONIGHT WITH THE INTERIOR REMAINING VFR.
THE CASCADES LIKELY REMAIN OBSCURED TODAY AND TONIGHT UNDER LIGHT
RAIN AND SNOW SHOWERS.
KPDX AND APPROACHES...PRIMARILY VFR CONDITIONS THROUGH TONIGHT.
WILL ALSO SEE A THREAT OF TSRA BETWEEN 24/18Z AND 25/03Z WHICH MAY
BRING BRIEF MVFR CIGS AND VIS. /MH /64
&&
.MARINE...HIGH PRES TO THE WEST OF THE WATERS WILL MAINTAIN
NORTHWESTERLY WINDS ACROSS THE WATERS TODAY. WINDS ARE EXPECTED TO
REMAIN BELOW ADVISORY CRITERIA BUT STILL EXPECT GUSTS TO 20 KT IN
THE COOL UNSTABLE AIR MASS. WINDS EASE LATER TONIGHT AND MONDAY AS
THE HIGH PRES SHIFTS OVER THE WATERS. MODELS CONTINUE TO SHOW A
WEAKENING FRONT APPROACHING LATE TUE OR WED...BUT IMPACTS LOOK TO
REMAIN MINIMAL. WILL LIKELY SEE GUSTY NORTHERLY WINDS DEVELOP LATE
IN THE WEEK AS THERMAL LOW PRES BUILDS OVER NORTHERN CALIFORNIA
AND SOUTHERN OREGON. MODELS ALSO CONTINUE TO SHOW ANOTHER WEAK
FRONT MOVING ACROSS THE WATERS NEXT WEEKEND.
SEAS CURRENTLY AROUND 8 FT EARLY THIS MORNING...BUT WILL BUILD TO
AROUND 10 FT BY NOON TODAY AND CONTINUE THROUGH MONDAY. SEAS LOOK
TO FALL BELOW 10 FT MONDAY AFTERNOON AND REMAIN BELOW ADVISORY
CRITERIA THROUGH THURSDAY. /MH /64
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 3 PM PDT MONDAY
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR
OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 10 AM
PDT THIS MORNING.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 PM
THIS AFTERNOON TO 10 PM PDT THIS EVENING.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
104 PM CDT SUN APR 24 2016
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...A MULTI-LEVEL CLOUD DECK PREVAILS ACROSS DEEP SOUTH
TEXAS THIS AFTERNOON WITH A MIX OF VFR/MVFR CEILINGS. WILL MENTION
TEMPO MVFR CEILINGS THROUGH AROUND 21Z BEFORE SOME LOW LEVEL
MIXING OCCURS. A MID LEVEL DISTURBANCE OVERHEAD WILL CONTINUE TO
MOVE EAST THIS AFTERNOON AND TODAY. NO WIDESPREAD CONVECTION IS
EXPECTED THROUGH THE NEXT 24 HOURS AS THE ATMOSPHERE HAS STABILIZED
ACROSS MUCH OF DEEP SOUTH TEXAS. HOWEVER...WILL INCLUDE VCSH AT
VALLEY TAF SITES THROUGH MID AFTERNOON FOR AN ISOLATED -SHRA OR
TWO. VFR TAFS OTHERWISE UNTIL LATE TONIGHT THEN MVFR CEILINGS
EXPECTED TO RETURN TO THE AREA. LIGHT TO MODERATE SOUTHEAST TO
SOUTH WINDS TODAY AND TONIGHT. VFR CONDITIONS DEVELOP ALONG WITH
BREEZY SOUTHEAST TO SOUTH WINDS AROUND MID-MORNING MONDAY.
&&
.PREV DISCUSSION... /ISSUED 916 AM CDT SUN APR 24 2016/
DISCUSSION...BROWNSVILLE RADAR SHOWS THE LARGE AREA OF
SHOWERS AND THUNDERSTORMS MOVING EAST OF THE LOWER TEXAS GULF
WATERS THIS MORNING. THE ATMOSPHERE HAS STABILIZED ACROSS MUCH OF
DEEP SOUTH TEXAS THIS MORNING IN THE WAKE OF THE OVERNIGHT
CONVECTION. THE COMBINATION OF THE APPROACHING UPPER LEVEL
DISTURBANCE...DAYTIME HEATING AND THE MOIST AIR MASS IN PLACE
WILL SUPPORT THE DEVELOPMENT OF CONVECTION THIS AFTERNOON. THE
STORM PREDICTION CENTER /SPC/ CONTINUES TO HAVE MOST OF DEEP SOUTH
TEXAS UNDER A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR TODAY.
MADE A QUICK UPDATE TO LOWER POPS FOR THIS MORNING AND MADE SOME
MINOR ADJUSTMENTS TO THE POP AND QPF GRIDS. NO OTHER CHANGES
NEEDED.
PREV DISCUSSION... /ISSUED 639 AM CDT SUN APR 24 2016/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...CEILINGS HAVE TEMPORARILY LIFTED...BUT THE MID LEVEL
DISTURBANCE MOVING OVER CENTRAL TEXAS MAY HAVE A BIT OF ENERGY
LEFT IN IT...WITH MVFR CEILINGS BUILT INTO THE TAFS FOR A FEW
HOURS FROM MID MORNING TO MID AFTERNOON...WITH ANY REMAINING
RESIDUAL RAIN CHANCES. VFR TAFS OTHERWISE UNTIL LATE TONIGHT.
WINDS WILL REMAIN LIGHT TO MODERATE SOUTHEAST.
PREV DISCUSSION... /ISSUED 428 AM CDT SUN APR 24 2016/
SHORT TERM /NOW THROUGH MONDAY/...A MID LEVEL SHORT WAVE TROUGH
WILL TRUNDLE ACROSS SOUTH CENTRAL TEXAS TODAY AND...WITH DAYTIME
HEATING...HAS PROMPTED A MARGINAL RISK OF SVR WEATHER CATEGORIZATION
FROM SPC. THE MAIN THREAT TODAY...AS SCATTERED THUNDERSTORMS DEVELOP
AND MOVE ACROSS THE AREA...WILL BE STRONG WIND GUSTS...FREQUENT
LIGHTNING...SMALL HAIL AND BRIEF HEAVY DOWNPOURS.
A ROUND OF SHOWERS AND THUNDERSTORMS HAS ALREADY MOVED THROUGH THE
AREA THIS MORNING...CONFIRMING THE THREAT FOR LIGHTNING...BRIEF
DOWNPOURS AND GUSTY WINDS...BUT RADAR ALSO SHOWS MORE DEVELOPMENT
TO THE SOUTH...AND THERE IS NO REASON TO BELIEVE THAT SOME
CONVECTION WILL NOT KEEP COMING THROUGH THE DAY. THE HRRR AND NAM
SHOW SOME QPF OVER EASTERN SECTIONS.
CONVECTION SHOULD END THIS EVENING...EXCEPT POSSIBLY FOR THE MARINE
AREAS...WITH IMPROVING CONDITIONS. LOOK FOR MODERATE SOUTHEAST WINDS
AND A MIX OF CLOUDS AND SUN ON MONDAY. HIGH TEMPS WILL RANGE FROM
THE 80S AT THE COAST TO THE UPPER 90S FAR WEST.
LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...THE ONLY OPPORTUNITY
FOR PRECIPITATION DURING THE LONG TERM PORTION OF THE FORECAST
WILL OCCUR ON WEDNESDAY...AS THE INTRUSION OF A WEAK COLD FRONT
INTO DEEP SOUTH TEXAS AND THE RIO GRANDE VALLEY COMBINES WITH
DECENT AVAILABLE MOISTURE AND DAYTIME HEATING TO PRODUCE ISOLATED
SHOWERS AND THUNDERSTORMS. THE REMAINDER OF THE FORECAST WILL BE
DRY WITH NO OTHER COLD FRONT PASSAGES OR SIGNIFICANT DISTURBANCES
AT THE 500 MB LEVEL. MAINLY PARTLY CLOUDY SKIES WILL SUPPORT WELL
ABOVE NORMAL DAYTIME HIGH AND OVERNIGHT LOW TEMPERATURES.
MARINE...NOW THROUGH MONDAY...LIGHT SOUTHEAST WINDS WILL INCREASE
TO HIGH END MODERATE THIS AFTERNOON AS HIGH PRESSURE OVER THE
NORTHWEST GULF INTERACTS WITH LOWER PRESSURE OVER THE HIGH PLAINS.
MODERATE WINDS WILL CONTINUE TONIGHT AND SEAS WILL BUILD...WITH
POSSIBLE SMALL CRAFT SHOULD EXERCISE CAUTION CONDITIONS. HIGH END
MODERATE WINDS WILL REPEAT ON MONDAY. SHOWERS AND THUNDERSTORMS
WILL BE POSSIBLE TODAY AS AN UPPER DISTURBANCE INFLUENCES THE
AREA.
MONDAY NIGHT THROUGH SATURDAY...SMALL CRAFT EXERCISE CAUTION
AND SMALL CRAFT ADVISORY WILL DOMINATE THROUGHOUT THE LONG
TERM PORTION OF THE MARINE FORECAST...WITH HIGH PRESSURE OVER
THE GULF OF MEXICO INTERACTING WITH LOWER PRESSURE INLAND.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
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