Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/25/16
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
849 PM PDT SUN APR 24 2016
.SYNOPSIS....WIND ADVISORY ALONG THE COAST THIS EVENING WITH GUSTY
NORTHWEST WINDS. CONTINUED COOL AND BREEZY ON MONDAY...OTHERWISE
DRY AND SEASONABLY COOL WEATHER IS FORECAST THROUGH TUESDAY. THERE
IS A CHANCE OF SHOWERS WEDNESDAY AND WEDNESDAY NIGHT AS A WEATHER
SYSTEM TRACKS ACROSS CALIFORNIA FROM NORTH TO SOUTH. LONG RANGE
TRENDS SUGGEST A SIGNIFICANT WARMING TREND BY LATE IN THE WEEK AND
INTO NEXT WEEKEND.
&&
.DISCUSSION...AS OF 8:49 PM PDT SUNDAY...A WIND ADVISORY REMAINS
IN EFFECT FOR COASTAL AREAS TIL MIDNIGHT TONIGHT. POST COLD
FRONTAL W-NW WINDS ARE WELL LINKED IN THE VERTICAL. PLUS SURFACE
WINDS ARE BEING DRIVEN BY MODERATE TO STRONG SURFACE PRESSURE
GRADIENTS ACV-SFO 7.2 MB AND SFO-SAC 4 MB. A MODERATE TO STRONG
UPPER LEVEL TROUGH ADVANCING EASTWARD OVER THE WEST COAST WILL
BECOME A CLOSED OFF LOW OVER NEVADA MONDAY THE LOW THEN REACHING
NORTHERN COLORADO TUESDAY.
SURFACE BASED INSTABILITY AROUND THE BAY AREA AND NORTH CENTRAL
COAST DURING THE AFTERNOON LED TO A FEW CUMULUS CLOUD BUILD-UPS
WELL INLAND AWAY FROM THE WATER. SINCE LATE AFTERNOON CONVECTIVE
INHIBITION OR NEGATIVE BUOYANCY HAS SETTLED IN OVER THE ENTIRE
REGION; IT SHOULD REMAIN DRY TONIGHT. RECENT HRRR AND NAM MODEL
FORECASTS HINT THAT THERE MAY BE AN ISOLATED SPRINKLE OR SHOWER
BETWEEN 11 PM TONIGHT - 5 AM MONDAY BUT NOT ENOUGH FOR AN UPDATE.
CLOSE TO OPTIMUM VERTICAL MIXING MAINTAINS THROUGH TONIGHT THUS
NOT ONLY DRYING OUT THE ATMOSPHERE BUT IT SHOULD HELP HOLD TEMPS
UP THROUGH THE NIGHT AS WELL. NORTH BAY INTERIOR VALLEYS WHERE
SURFACE WINDS DE-COUPLE COULD HAVE UPPER 30S MONDAY MORNING.
A PROGRESSIVE WX PATTERN CONTINUES ACROSS THE EASTERN PACIFIC INTO
NORTH AMERICA. 500 MB HEIGHTS WILL REBOUND BACK TO NORMAL OR SLIGHTLY
ABOVE TUESDAY THEN LOWER WED-THU AS ANOTHER TROUGH WITH SHOWERS SWINGS
EASTWARD OVER THE AREA. THERE`S RECENTLY BEEN GOOD RUN TO RUN MODEL
AGREEMENT INDICATING ABOVE NORMAL RIDGING RETURNS TO THE AREA LATE
THIS WEEK BUT THERE`S SOME DISAGREEMENT THEREAFTER AS TO HOW QUICKLY
THE 500 MB HEIGHT RIDGE DISSIPATES EARLY NEXT WEEK. AS MENTIONED IN
THE PREVIOUS DISCUSSION THERE`S POTENTIAL FOR A SIGNIFICANT WARMING
TREND LATE IN THE WEEK AND NEXT WEEKEND.
&&
.PREV DISCUSSION...AS OF 3:00 PM PDT SUNDAY...WIND ADVISORY IN EFFECT
FOR COASTAL AREAS. SO FAR WE`VE SEEN GUSTS TO AROUND 45 MPH AT PT
REYES WITH 43 MPH KSFO AND SOME 35-40 MPH IN THE MARIN HILLS.
WINDS ARE FORECAST TO PEAK LATE THIS AFTERNOON AND EARLY EVENING
AS THE MAIN TROUGH AXIS PASSES OVERHEAD AND STRONGER COLD
ADVECTION ARRIVES OVER THE AREA. MUCH LIGHTER WINDS ARE OCCURRING
JUST A FEW MILES INLAND WITH AFTERNOON READINGS INTO THE 60S.
SKIES WILL BE MOSTLY CLEAR OVERNIGHT AND CHILLY LATE APRIL
TEMPERATURES ARE IN STORE BUT ENOUGH BOUNDARY LAYER MIXING TO
PRECLUDE ANYTHING TOO COLD.
MONDAY WILL BE A PARTLY CLOUDY AND SEASONABLY COOL DAY WITH SOME
CONTINUED BLUSTERY WINDS RIGHT ALONG THE COAST AND HILLS AS
ANOTHER COLD SHORTWAVE PASSES TO OUR EAST AND GENERATES SHOWERS
OVER THE SIERRA. HIGHS ON MONDAY WILL STAY IN THE 60S ONCE
AGAIN...EVEN FOR INLAND AREAS WHERE DAYTIME NORMAL ARE NOW AROUND
THE MIDDLE 70S.
NO BIG CHANGES FOR TUESDAY BUT SOME SHORTWAVE RIDGING WILL ALLOW
FOR A FEW DEGREES OF WARMING WITH SOME LOWER 70S SHOWING UP BY
TUESDAY AFTERNOON.
BY EARLY WEDS MORNING SHOWER CHANCES RETURN TO THE FORECAST WITH
THE MODELS SHOWING SOME LIGHT SHOWERS AS EARLY AS 12Z WEDS FROM A
COLD BUT FAIRLY DRY SYSTEM APPROACHING FROM THE NW. THE ECMWF HAS
HAD THIS SCENARIO FEATURED FOR DAYS NOW BUT THE OVERALL TREND HAS
BEEN DRIER. NONETHELESS IT DOES LOOK LIKE A PRETTY GOOD CHANCE OF
SHOWERS FOR WEDS. IN GENERAL THE MODELS HAVE BEEN PAINTING THE
SANTA CRUZ MTNS AND BIG SUR HILLS AS THE BEST LOCATIONS TO SEE
SHOWERS ON WEDS...ALONG WITH SOME OF THE INTERIOR HILLS DUE TO
CONVECTIVE AFTERNOON SHOWERS. FOR NOW THE FORECAST IS FAIRLY
BROADBRUSH WITH CHANCE OF SHOWERS AND QPF TOTALS 0.15-0.25 ON
AVERAGE. THE WEDS SYSTEM WILL BE COLD AS WELL WITH 850 MB TEMPS
DOWN TO AROUND 4 CELSIUS. ANY SHOWERS WILL LIKELY END AS THE SUN
GOES DOWN WEDS EVENING.
THURSDAY WILL BE A DRY BUT COOL DAY AS THE TROUGH MOVES EAST WITH
CONTINUED DRY BUT CHILLY NORTHERLY WINDS.
MODELS NOW STARTING TO SHOW A POTENTIALLY SIGNIFICANT WARMING
TREND GETTING UNDERWAY BY FRIDAY BUT PEAKING LATER NEXT WEEKEND AS
A RIDGE BUILDS...THERMAL TROUGH PUSHES TO THE COAST AND PERIODS OF
OFFSHORE WINDS ENSUE. ECMWF HAS 850 MB TEMPS TO 18 CELSIUS BY
THIS TIME NEXT WEEKEND.
&&
.AVIATION...AS OF 4:50 PM PDT SUNDAY...MAINLY HIGH CLOUDS EXPECTED
ACROSS AREA TERMINALS THROUGH TONIGHT. GUSTY WEST WINDS WILL
PREVAIL THROUGH TONIGHT AND INTO MONDAY AS THE TROUGH AXIS MOVES
ACROSS THE REGION. BREEZY CONDITIONS AND COLD AIR ADVECTION WILL
KEEP STRATUS FROM FORMING TONIGHT. HIGH CONFIDENCE.
VICINITY OF KSFO...VFR CONDITIONS EXPECTED THROUGH THE PERIOD.
STRONG AND GUSTY WEST WINDS SUSTAINED BETWEEN 25 TO 35 KT WITH
GUSTS TO 45 KT WILL PREVAIL THROUGH LATE TONIGHT. WINDS WILL
DIMINISH ACROSS THE AREA AFTER 06Z BUT REMAIN BREEZY INTO MONDAY.
AN AIRPORT WEATHER WARNING IS IN EFFECT TILL 06Z FOR KSFO. HIGH
CONFIDENCE.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY TERMINALS...VFR CONDITIONS EXPECTED THROUGH THE PERIOD.
STRONG AND GUSTY WEST WINDS SUSTAINED BETWEEN 15 TO 25 KT WITH
GUSTS AROUND 30 KT WILL PREVAIL THROUGH MUCH OF TONIGHT. HIGH
CONFIDENCE.
&&
.MARINE...AS OF 2:56 PM PDT SUNDAY...FREQUENT GALE FORCE GUSTS
ARE EXPECTED THROUGH MONDAY EVENING AS COLD AIR RUSHES IN BEHIND A
DEPARTING FRONT. THESE STRONG WINDS WILL RESULT IN STEEP CHOPPY
SEAS ACROSS THE COASTAL WATERS THROUGH MONDAY EVENING. WINDS WILL
EASE SLIGHTLY TUESDAY BUT ARE ANTICIPATED TO INCREASE ONCE AGAIN
THE SECOND HALF OF THE WEEK.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...WIND ADVISORY...COASTAL ZONES FOR SF BAY AREA AND
SOUTHERN MONTEREY BAY AND BIG SUR COAST TIL MIDNIGHT
GLW...PT ARENA TO PT REYES 0-10 NM
GLW...PT REYES TO PIGEON PT 0-10 NM
GLW...PIGEON PT TO PT PINOS 0-10 NM
GLW...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
GLW...PT ARENA TO PIGEON PT 10-60 NM
GLW...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM
SCA...ROUGH BAR ADVISORY FOR SF BAR
SCA...MRY BAY
GLW...SF BAY UNTIL 3 AM
&&
$$
PUBLIC FORECAST: CANEPA/R_WALBRUN
AVIATION: CW
MARINE: BELL
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AREA FORECAST DISCUSSION
NWS PHOENIX AZ
225 AM MST SAT APR 23 2016
.SYNOPSIS...
TEMPERATURES WILL BE ON A DOWNHILL TREND THIS WEEKEND AS THE FIRST OF
THREE LOW PRESSURE SYSTEMS MOVES THROUGH THE REGION TODAY. HIGHS
WILL DROP INTO THE 80S...POSSIBLY EVEN INTO THE 70S THROUGH NEXT
WEEK. THE SECOND SYSTEM WILL AFFECT THE REGION LATE MONDAY INTO
TUESDAY BRINGING BREEZY TO WINDY CONDITIONS BUT WITH LITTLE CHANCE
FOR ANY RAINFALL. ANOTHER STORM SYSTEM IS LIKELY FOR LATE NEXT WEEK
WITH AT LEAST SOME CHANCE OF RAIN POSSIBLE.
&&
.DISCUSSION...
AFTER SEVERAL DAYS OF VERY WARM TEMPERATURES...SOME RELIEF IS IN
SIGHT AS A COUPLE MAINLY DRY WEATHER SYSTEMS WILL BRING IN COOLER AIR
THROUGH EARLY NEXT WEEK. THE FIRST ONE IS CURRENTLY SITUATED OVER THE
GREAT BASIN AND WILL TRACK THROUGH UTAH TODAY...THUS STAYING WELL
NORTH OF OUR AREA. EVEN WITH THE NORTHERN TRACK OF THIS
SYSTEM...HEIGHTS ALOFT WILL LOWER ALONG WITH MODEST COOLING ALSO
TAKING PLACE. BREEZY WESTERLY WINDS ARE AGAIN EXPECTED TODAY UNDER AN
INCREASED PRESSURE GRADIENT...BUT GUSTS SHOULD REMAIN BELOW 25 MPH.
THE COOLING ALOFT...ROUGHLY 5C OF COOLING AT 850MB...WILL RESULT IN
HIGHS TODAY AND SUNDAY FALLING TO NEAR SEASONAL NORMALS.
WE WILL BE IN BETWEEN SYSTEMS ON SUNDAY WITH FAIRLY ZONAL FLOW
AFFECTING THE DESERT SOUTHWEST. THE SECOND LOW PRESSURE TROUGH WILL
BEGIN TO DROP OUT OF THE PACIFIC NORTHWEST AT THIS TIME WITH SOME
DEEPENING OCCURRING AS IT MOVES INTO THE GREAT BASIN ON MONDAY. THIS
SYSTEM WILL BE BETTER SUPPORTED ALOFT COMPARED TO THE FIRST ONE
CURRENTLY MOVING PAST TO OUR NORTH AND THUS WILL DEEPEN FURTHER AS IT
APPROACHES THE DESERT SOUTHWEST. MODEL ENSEMBLES SHOW VERY LITTLE
DIFFERENCES...SO CONFIDENCE IS HIGH THAT THIS STORM TRACK WILL BE
FURTHER SOUTH...LIKELY MOVING ACROSS NORTHERN ARIZONA EARLY TUESDAY.
DESPITE THE STRONGER DYNAMICS AND A MORE SOUTHERLY TRACK...THE LACK
OF ANY DECENT MOISTURE TO WORK WITH WILL KEEP RAIN CHANCES CONFINED
TO THE NORTHERN HALF OF ARIZONA. FOR OUR AREA THE BIGGEST IMPACT WILL
BE THE LIKELIHOOD OF STRONG WINDS MOVING IN LATER MONDAY. A WIND
ADVISORY WILL LIKELY BE NEEDED FOR SOUTHEAST CALIFORNIA AND MAYBE
PORTIONS OF SOUTHWEST ARIZONA FOR MONDAY AFTERNOON AND EVENING. THE
STRONG WINDS WILL SURELY GIVE RISE TO PATCHY AREAS OF BLOWING DUST
POSING SOME LOCALIZED VISIBILITY ISSUES.
EVEN MORE COOLER AIR IS EXPECTED TO MOVE IN ON TUESDAY AND WEDNESDAY
AS HIGHS SHOULD DROP TO BELOW NORMAL LEVELS. THESE COOLER CONDITIONS
WILL LIKELY CONTINUE THROUGH THE REST OF NEXT WEEK AS ANOTHER
POTENTIAL UPPER LOW IS ADVERTISED FOR THURSDAY AND FRIDAY. FOR NOW
THIS SYSTEM SHOWS A HIGHER LIKELIHOOD OF PRODUCING SOME RAIN ACROSS
SOUTHERN CALIFORNIA AND ARIZONA AS IT SHOULD HAVE MORE RESIDENCE TIME
OFF THE COAST OF CALIFORNIA AND THUS ADVECT BETTER MOISTURE INTO OUR
REGION. HAVE INCLUDED MAINLY SLIGHT CHANCE POPS IN THE FORECAST FOR
THIS TIME PERIOD AND WILL MONITOR CLOSELY FOR ANY NEEDED ADJUSTMENTS
TO POPS. THE CONTINUED BELOW NORMAL TEMPERATURES SEEMS VERY LIKELY
THROUGH THE END OF NEXT WEEK AS RELATIVELY LOW HEIGHTS ALOFT PERSIST
UNDER THIS UNSETTLED WEATHER REGIME.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL...AND
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
OCCASIONAL STRONG WIND GUSTS WILL BE THE MAIN AVIATION CONCERN
THROUGH SATURDAY AFTERNOON. A FEW W/SW GUSTS 20-25KT THROUGH THE
PHOENIX METRO AND 25-30KT OVER SERN CALIFORNIA WILL BE COMMON IN THE
EVENING BEFORE BETTER DECOUPLING OCCURS. THE WESTERLY COMPONENT
SHOULD HOLD MUCH LONGER INTO THE OVERNIGHT FOR THE PHOENIX TERMINALS
THAN IS TYPICAL. OCCASIONAL GUSTS WILL BE POSSIBLE AGAIN SATURDAY
AFTERNOON...THOUGH SPEEDS WEAKER THAN TODAY.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
A SERIES OF LOW PRESSURE SYSTEMS WILL MOVE NORTH OF THE REGION
THROUGH LATE NEXT WEEK...WHICH WILL KEEP TEMPERATURES GENERALLY AT
OR BELOW NORMAL. SEASONABLY BREEZY CONDITIONS ARE EXPECTED EACH
AFTERNOON AS WELL. WINDS WILL BE SOMEWHAT STRONGER MONDAY AHEAD OF
THE SECOND LOW PRESSURE SYSTEM...THOUGH CRITICAL FIRE WEATHER
CONDITIONS ARE NOT ANTICIPATED. A MORE DISCERNIBLE INCREASE IN
MOISTURE IS EXPECTED AHEAD OF A STORM SYSTEM THURSDAY...WHICH WILL
BRING A SLIGHT CHANCE OF PRECIPITATION THROUGH FRIDAY.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION IS NOT EXPECTED.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...KUHLMAN
AVIATION...MO
FIRE WEATHER...HIRSCH
Area Forecast Discussion...UPDATED
National Weather Service Reno NV
1022 PM PDT FRI APR 22 2016
.UPDATE...
Latest radar trends show a rapid decrease in both intensity and
coverage of snow showers as instability/convection decrease across
the interior valleys of northern CA. The upper level shortwave
will exit late tonight with drier and more stable airmass to bring
an end to showers Saturday. Temperatures will remain below
freezing overnight where snow fell today. Therefore roads will see
little improvement until treated. The snow advisory will expire at
11 pm. However, anyone planning travel during the overnight hours
should check the latest road conditions.
&&
.SYNOPSIS...
A break in the wet weather is expected Saturday before more
showers arrive Sunday into Monday. Unsettled weather will continue
through next week with below average temperatures.
&&
.PREVIOUS DISCUSSION... /Issued 736 PM PDT FRI APR 22 2016/
UPDATE...
The cold front has moved completely through western NV as of early
this evening and gradients have relaxed enough to go ahead and
drop the wind advisories and areas of blowing dust. Winds will
still be locally gusty before subsiding further this evening, but
well below earlier peaks.
Convection continues to fire over the Sacramento Valley and then
move eastward into the Tahoe Basin. Moderate to heavy snow was
falling under some of the stronger showers with roads likely to
remain a mess this evening, especially with the sun setting.
Expect another 1 to 3 inches, locally up to 4 inches this evening
before showers begin to diminish. We will continue the snow
advisory through expiration. Scattered snow showers may also
produce periods of slick roads along Hwy 395 through Mono County.
Make sure to check road conditions if you must travel tonight.
Hohmann
SYNOPSIS...
Moderate to occasionally heavy bands of snow showers will continue
across the Tahoe Basin through this evening with showers more
scattered elsewhere tonight. A break is expected Saturday before
more showers arrive Sunday into Monday. Unsettled weather will
continue through next week with below average temperatures.
PREVIOUS DISCUSSION... /Issued 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...None.
CA...None.
&&
$$
For more information from the National Weather Service visit...
http://weather.gov/reno
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
945 PM PDT FRI APR 22 2016
.SYNOPSIS....A FEW SHOWERS WILL LINGER INTO THE EVENING HOURS AND
END BY MIDNIGHT. 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 9:00 PM PDT FRIDAY...POST-FRONTAL SHOWER
ACTIVITY HAS BEEN GRADUALLY TAPERING OFF SINCE EARLY EVENING.
RADAR CURRENTLY SHOWS ISOLATED LIGHT SHOWERS FROM THE CENTRAL SF
BAY AREA SOUTH TO MONTEREY COUNTY. BASED ON LATEST HRRR AND NAM
MODELS WE CAN EXPECT ALL SHOWER ACTIVITY TO END BY MIDNIGHT.
DRY WEATHER IS FORECAST OVER THE WEEKEND ALONG WITH SLIGHTLY
COOLER THAN NORMAL TEMPERATURES. AN "INSIDE SLIDER" IS FORECAST TO
DROP ACROSS NORTHEAST CALIFORNIA LATE SUNDAY AND SUNDAY NIGHT. ALL
PRECIP WITH THIS SYSTEM IS FORECAST TO REMAIN TO OUR NORTH AND
EAST. THE PRIMARY IMPACT THIS SYSTEM WILL HAVE ON OUR WEATHER WILL
BE TO GENERATE SOME LOCALLY STRONG AND GUSTY NORTHWEST WINDS FROM
LATE SUNDAY INTO MONDAY. STRONGEST WINDS BE ALONG THE COAST AND IN
THE HILLS. WINDS MAY GUST LOCALLY TO 40 MPH AND THIS MAY BE A
MARGINAL WIND ADVISORY SCENARIO. WINDS SHOULD EASE IN ALL AREAS BY
MONDAY NIGHT.
OUR NEXT POTENTIAL FOR RAINFALL WILL BE AROUND THE MIDDLE OF NEXT
WEEK WHEN A SYSTEM IS DUE TO DROP IN FROM THE NORTHWEST. THE 18Z
GFS FORECASTS WIDESPREAD SHOWER ACTIVITY WITH THIS SYSTEM FROM
WEDNESDAY AFTERNOON THROUGH WEDNESDAY NIGHT. THE LATEST ECMWF
(12Z) IS NOT AS OPTIMISTIC AS THE GFS...SHOWING ONLY ISOLATED
LIGHT QPF DURING THE SAME PERIOD OF TIME.
&&
.AVIATION...AS OF 9:45 PM PDT FRIDAY...ISOLATED SHOWERS WILL
TAPER OFF THIS EVENING. ADDITIONAL MAINLY WEAK LOWER LEVEL
ATMOSPHERIC COOLING IS FORECAST TONIGHT WHILE A MID-UPPER LEVEL
HIGH PRESSURE AREA STEADILY BUILDS OVER NORCAL TONIGHT AND
SATURDAY.
VICINITY OF KSFO...VFR. WESTERLY WINDS 10-15 KNOTS TONIGHT AND
SATURDAY MORNING...GUSTS TO NEAR 20 KNOTS POSSIBLE SAT AFTERNOON.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY TERMINALS...VFR. MAINLY LIGHT WINDS.
&&
.MARINE...AS OF 9:29 PM PDT FRIDAY...A COLD FRONT WILL SWEEP
SOUTHEAST OVER 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...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: DYKEMA
AVIATION/MARINE: CANEPA
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AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
323 PM MDT SAT APR 23 2016
.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 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 233 PM MDT SAT APR 23 2016
AVIATION...VFR CONDITIONS EXPECTED. SOUTHWEST TO WEST WINDS
THRU 01Z 20-30 KTS THEN SOUTHWEST/SOUTH WINDS WITH THE STRONGER
GUSTS SUBSIDING AT KDEN/KAPA 04-05Z. DO NOT ANTICPATE TSTMS AT
THIS TIME BUT WL KEEP VCSH THROUGH 05Z. HIGH BASED SHOWERS COULD
PRODUCE GUSTS 40-45KT. 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.
&&
$$
SHORT TERM...COOPER
LONG TERM...BARJENBRUCH
AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1016 AM MDT SAT APR 23 2016
.UPDATE...
ISSUED AT 1013 AM MDT SAT APR 23 2016
STRONG WINDS ALREADY DEVELOPING ABOVE TIMBERLINE THIS MORNING SO
HAVE UPDATED TO GRIDS TO ACCOUNT FOR STRONGER GUSTS IN THE
MOUNTAINS TODAY. MOSTLY CLOUDY ACROSS MUCH OF THE URBAN CORRIDOR
AND NORTHEAST PLAINS TODAY TOO. AS A RESULT...I SHAVED A DEGREE
OR TWO OF THE MAX TEMPERATURES BUT STILL QUITE MILD.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM MDT SAT APR 23 2016
SOUTHWEST WINDS ALOFT WILL BE INCREASING TODAY AHEAD OF AN
APPROACHING UPPER TROUGH THAT IS OVER WESTERN UTAH THIS MORNING.
AS DAYTIME WARMING INCREASES THE DEPTH OF THE BOUNDARY LAYER...THE
WINDS ALOFT ARE EXPECTED TO MIX DOWN TO THE SURFACE...BRINGING
GUSTY WINDS TO THE PLAINS THROUGH THE AFTERNOON. THE LATEST RUNS
OF THE HRRR MODEL HAVE BEEN SHOWING A CONSOLIDATED BAND OF SHOWERS
ASSOCIATED WITH THE TROUGH AXIS MOVING OVER THE MOUNTAINS AFTER
22Z. LIGHTNING HAS BEEN DETECTED THIS MORNING OVER
UTAH...INDICATING THE INSTABILITY OF THE AIRMASS THAT WILL
ACCOMPANY THE UPPER TROUGH AS IT MOVES ACROSS THE STATE. MODEL
SOUNDINGS SHOW THAT FREEZING LEVELS WILL BE AROUND 12000 FEET MSL
AHEAD OF THE TROUGH...SO THE MOUNTAINS WILL SEE A MIX OF RAIN AND
SNOW WITH THE AFTERNOON SHOWERS...WITH THE SNOW LEVELS DROPPING
LATER IN THE EVENING. MODEL SOUNDINGS ALSO SHOW THE AIRMASS WILL
BE QUITE DRY ON THE PLAINS...MAKING IT TOUGH FOR ANY RAIN TO
REACH THE GROUND ON THE PLAINS. HOWEVER...GUSTY WINDS ARE EXPECTED
THROUGH THE LATE AFTERNOON AND EVENING DUE TO DOWNBURSTS FROM
VIRGA SHOWERS AND THE SOUTHWEST FLOW AT MID-LEVELS BEING MIXED
DOWN TO THE SURFACE. AS THE UPPER TROUGH MOVES EASTWARD AND ONTO
THE PLAINS...SHOWER ACTIVITY OVER THE MOUNTAINS AND PLAINS WILL BE
DECREASING BY MIDNIGHT. TEMPERATURES WILL ALSO COOL DOWN LATER
TONIGHT AS THE POST-TROUGH AIRMASS MOVES IN.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 412 AM MDT SAT APR 23 2016
AN UPPER LEVEL STORM SYSTEM WILL BE CENTERED OVER ERN WY EARLY ON
SUN AND THEN WILL MOVE SLOWLY EAST INTO SCNTRL SOUTH DAKOTA AND
NCNTRL NEBRASKA BY EARLY SUN EVENING. COMBINATION OF RATHER STG SFC
GRADIENT AND QG DOWNWARD DESCENT WILL ALLOW FOR STG WINDS IN THE
MORNING ESPECIALLY ACROSS THE NRN FOOTHILLS AND HIGHER MTNS. WOULD
NOT BE SURPRISED TO SEE A SOME SPOTS RECEIVE HIGH WIND CRITERIA
FOR A FEW HOURS. MEANWHILE GUSTY WINDS WILL ALSO OCCUR OVER THE
PLAINS BUT SPEEDS SHOULD STAY BLO HIGH WIND CRITERIA.
AS FAR AS PCPN CROSS-SECTIONS CONTINUE TO SHOW FAVORABLE OROGRAPHICS
AND LINGERING MOISTURE IN THE NRN MTNS MAINLY NR THE WY BORDER WITH
ADVISORY AMOUNTS POSSIBLE IN ZN 31. OTHERWISE MAY SEE A FEW AFTN
SHOWERS ACROSS THE PLAINS NEAR THE WY-NE BORDER. AS FOR HIGHS
READINGS WILL DROP BACK INTO THE 65 TO 70 DEGREE RANGE ACROSS NERN
CO.
BY MON THE FLOW ALOFT WILL BECOME SWLY AS ANOTHER STORM SYSTEM
MOVES INTO THE GREAT BASIN. MEANWHILE SFC LOW PRES WILL INTENSIFY
ALONG THE FOOTHILLS WITH GUSTY SSE WINDS ACROSS THE PLAINS BY
AFTN. AS FOR PCPN POTENTIAL...MOISTURE WILL INCREASE BY AFTN IN
THE MTNS AND COMBINE WITH FAVORABLE LAPSE RATES FOR SOME SCT
SHOWERS AND POSSIBLE A FEW TSTMS. OVER NERN CO IT WILL BE DRY
ALTHOUGH THERE COULD BEA FEW LATE AFTN HIGH BASED STORMS ALONG THE
FRONT RANGE. AS FOR HIGHS READINGS WILL BE IN THE MID 60S TO LOWER
70S ACROSS THE PLAINS.
FOR MON NIGHT THRU TUE ONCE AGAIN ITS NOT CLEAR HOW THE UPPER LEVEL
STORM SYSTEM WILL EVOLVE. IT APPEARS ONCE PIECE OF ENERGY MAY
MOVE NNE INTO THE NRN ROCKIES WHILE SIGNIFICANT ENERGY REFORMS
INTO A CLOSED LOW NEAR THE FOUR CORNERS AREA BY TUE. MEANWHILE
THE MAIN SFC LOW MAY INTENSIFY OVER SERN CO WITH DEEPER LOW LVL
MOISTURE ADVECTING INTO NERN CO NORTH OF A WRM FNT. OVERALL SHOULD
SEE A CHC OF SHOWERS AND TSTMS ESPECIALLY ACROSS THE PLAINS MON
NIGHT. ON TUE BEST CHC OF SHOWERS AND TSTMS WILL BE IN THE AFTN
ACROSS THE AREA. THERE ALSO COULD BE SOME THREAT OF STRONGER
STORMS ACROSS PORTIONS OF THE PLAINS TUE AFTN NEAR THE TRIPLE
POINT AND JUST NORTH OF THE WRM FRONT.
BY TUE NIGHT INTO WED THERE IS SOME POTENTIAL THAT THE UPPER LEVEL
LOW NEAR THE FOUR CORNERS WILL INTENSIFY AND MOVE INTO SERN CO BY
12Z WED AND THEN LIFT NORTHEAST INTO NWRN KANSAS/SWRN NEBRASKA BY
WED AFTN. IF THIS OCCURS THEN THERE COULD BE SOME SIGNIFICANT PCPN
TUE NIGHT INTO WED ACROSS PORTIONS OF NRN CO. BUFFER SOUNDINGS SHOW
TEMPS WILL BE WRM ENOUGH FOR PCPN TO FALL MOSTLY AS RAIN ACROSS THE
PLAINS WITH THE SNOW LEVEL ABOVE 6000 FT.
FOR WED NIGHT INTO THU THE UPPER LEVEL LOW IS FCST TO MOVE ENE OF
THE AREA AS ANOTHER SYSTEM DIVES INTO SRN CALIFORNIA. THUS SHOULD
SEE DRIER CONDITIONS WED NIGHT INTO THU. HOWEVER LINGERING MOISTURE
COMBINED WITH AFTN HEATING MAY LEAD TO A SLIGHT CHC OF SHOWERS AND
TSTMS ACROSS THE HIGHER TERRAIN AND ALONG THE FRONT RANGE.
BY FRI THE ECMWF AND GFS WANT TO EJECT THE LOW FM SRN CALIFORNIA
INTO THE FOUR CORNERS AREA BY FRI AFTN WHILE THE CANADIAN MODEL IS
CONSIDERABLY SLOWER AND FUTHER SW. THIS FAR OUT HARD TO SAY WHAT
WILL HAPPEN WITH THIS NEXT FEATURE. FOR NOW WILL JUST GO WITH CHC
POPS IN THE MTNS WITH A SLIGHT CHC OVER THE PLAINS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1013 AM MDT SAT APR 23 2016
VFR CONDITIONS EXPECTED. SOUTH TO SOUTHWEST WINDS WILL BE
INCREASING THROUGH THIS AFTERNOON AS A SURFACE TROUGH DEEPENS OVER
THE EASTERN PLAINS. GUSTS UP TO 30 MPH CAN BE EXPECTED BY LATE
THIS AFTERNOON. CONVECTION IS EXPECTED OVER THE FOOTHILLS THIS
AFTERNOON WHICH COULD MOVE OUT OVER THE URBAN CORRIDOR DURING THE
EVENING AS THE MAIN UPPER TROUGH PROGRESSES EASTWARD. GUSTY WINDS
BUT LITTLE PRECIPITATION IS EXPECTED FROM THE HIGH BASED SHOWERS.
GUSTS 40-50 MPH WILL BE POSSIBLE WITH THE EARLY EVENING SHOWER
ACTIVITY.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...COOPER
SHORT TERM...DANKERS
LONG TERM...RPK
AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
412 AM MDT SAT APR 23 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM MDT SAT APR 23 2016
SOUTHWEST WINDS ALOFT WILL BE INCREASING TODAY AHEAD OF AN
APPROACHING UPPER TROUGH THAT IS OVER WESTERN UTAH THIS MORNING.
AS DAYTIME WARMING INCREASES THE DEPTH OF THE BOUNDARY LAYER...THE
WINDS ALOFT ARE EXPECTED TO MIX DOWN TO THE SURFACE...BRINGING
GUSTY WINDS TO THE PLAINS THROUGH THE AFTERNOON. THE LATEST RUNS
OF THE HRRR MODEL HAVE BEEN SHOWING A CONSOLIDATED BAND OF SHOWERS
ASSOCIATED WITH THE TROUGH AXIS MOVING OVER THE MOUNTAINS AFTER
22Z. LIGHTNING HAS BEEN DETECTED THIS MORNING OVER
UTAH...INDICATING THE INSTABILITY OF THE AIRMASS THAT WILL
ACCOMPANY THE UPPER TROUGH AS IT MOVES ACROSS THE STATE. MODEL
SOUNDINGS SHOW THAT FREEZING LEVELS WILL BE AROUND 12000 FEET MSL
AHEAD OF THE TROUGH...SO THE MOUNTAINS WILL SEE A MIX OF RAIN AND
SNOW WITH THE AFTERNOON SHOWERS...WITH THE SNOW LEVELS DROPPING
LATER IN THE EVENING. MODEL SOUNDINGS ALSO SHOW THE AIRMASS WILL
BE QUITE DRY ON THE PLAINS...MAKING IT TOUGH FOR ANY RAIN TO
REACH THE GROUND ON THE PLAINS. HOWEVER...GUSTY WINDS ARE EXPECTED
THROUGH THE LATE AFTERNOON AND EVENING DUE TO DOWNBURSTS FROM
VIRGA SHOWERS AND THE SOUTHWEST FLOW AT MID-LEVELS BEING MIXED
DOWN TO THE SURFACE. AS THE UPPER TROUGH MOVES EASTWARD AND ONTO
THE PLAINS...SHOWER ACTIVITY OVER THE MOUNTAINS AND PLAINS WILL BE
DECREASING BY MIDNIGHT. TEMPERATURES WILL ALSO COOL DOWN LATER
TONIGHT AS THE POST-TROUGH AIRMASS MOVES IN.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 412 AM MDT SAT APR 23 2016
AN UPPER LEVEL STORM SYSTEM WILL BE CENTERED OVER ERN WY EARLY ON
SUN AND THEN WILL MOVE SLOWLY EAST INTO SCNTRL SOUTH DAKOTA AND
NCNTRL NEBRASKA BY EARLY SUN EVENING. COMBINATION OF RATHER STG SFC
GRADIENT AND QG DOWNWARD DESCENT WILL ALLOW FOR STG WINDS IN THE
MORNING ESPECIALLY ACROSS THE NRN FOOTHILLS AND HIGHER MTNS. WOULD
NOT BE SURPRISED TO SEE A SOME SPOTS RECEIVE HIGH WIND CRITERIA
FOR A FEW HOURS. MEANWHILE GUSTY WINDS WILL ALSO OCCUR OVER THE
PLAINS BUT SPEEDS SHOULD STAY BLO HIGH WIND CRITERIA.
AS FAR AS PCPN CROSS-SECTIONS CONTINUE TO SHOW FAVORABLE OROGRAPHICS
AND LINGERING MOISTURE IN THE NRN MTNS MAINLY NR THE WY BORDER WITH
ADVISORY AMOUNTS POSSIBLE IN ZN 31. OTHERWISE MAY SEE A FEW AFTN
SHOWERS ACROSS THE PLAINS NEAR THE WY-NE BORDER. AS FOR HIGHS
READINGS WILL DROP BACK INTO THE 65 TO 70 DEGREE RANGE ACROSS NERN
CO.
BY MON THE FLOW ALOFT WILL BECOME SWLY AS ANOTHER STORM SYSTEM
MOVES INTO THE GREAT BASIN. MEANWHILE SFC LOW PRES WILL INTENSIFY
ALONG THE FOOTHILLS WITH GUSTY SSE WINDS ACROSS THE PLAINS BY
AFTN. AS FOR PCPN POTENTIAL...MOISTURE WILL INCREASE BY AFTN IN
THE MTNS AND COMBINE WITH FAVORABLE LAPSE RATES FOR SOME SCT
SHOWERS AND POSSIBLE A FEW TSTMS. OVER NERN CO IT WILL BE DRY
ALTHOUGH THERE COULD BEA FEW LATE AFTN HIGH BASED STORMS ALONG THE
FRONT RANGE. AS FOR HIGHS READINGS WILL BE IN THE MID 60S TO LOWER
70S ACROSS THE PLAINS.
FOR MON NIGHT THRU TUE ONCE AGAIN ITS NOT CLEAR HOW THE UPPER LEVEL
STORM SYSTEM WILL EVOLVE. IT APPEARS ONCE PIECE OF ENERGY MAY
MOVE NNE INTO THE NRN ROCKIES WHILE SIGNIFICANT ENERGY REFORMS
INTO A CLOSED LOW NEAR THE FOUR CORNERS AREA BY TUE. MEANWHILE
THE MAIN SFC LOW MAY INTENSIFY OVER SERN CO WITH DEEPER LOW LVL
MOISTURE ADVECTING INTO NERN CO NORTH OF A WRM FNT. OVERALL SHOULD
SEE A CHC OF SHOWERS AND TSTMS ESPECIALLY ACROSS THE PLAINS MON
NIGHT. ON TUE BEST CHC OF SHOWERS AND TSTMS WILL BE IN THE AFTN
ACROSS THE AREA. THERE ALSO COULD BE SOME THREAT OF STRONGER
STORMS ACROSS PORTIONS OF THE PLAINS TUE AFTN NEAR THE TRIPLE
POINT AND JUST NORTH OF THE WRM FRONT.
BY TUE NIGHT INTO WED THERE IS SOME POTENTIAL THAT THE UPPER LEVEL
LOW NEAR THE FOUR CORNERS WILL INTENSIFY AND MOVE INTO SERN CO BY
12Z WED AND THEN LIFT NORTHEAST INTO NWRN KANSAS/SWRN NEBRASKA BY
WED AFTN. IF THIS OCCURS THEN THERE COULD BE SOME SIGNIFICANT PCPN
TUE NIGHT INTO WED ACROSS PORTIONS OF NRN CO. BUFFER SOUNDINGS SHOW
TEMPS WILL BE WRM ENOUGH FOR PCPN TO FALL MOSTLY AS RAIN ACROSS THE
PLAINS WITH THE SNOW LEVEL ABOVE 6000 FT.
FOR WED NIGHT INTO THU THE UPPER LEVEL LOW IS FCST TO MOVE ENE OF
THE AREA AS ANOTHER SYSTEM DIVES INTO SRN CALIFORNIA. THUS SHOULD
SEE DRIER CONDITIONS WED NIGHT INTO THU. HOWEVER LINGERING MOISTURE
COMBINED WITH AFTN HEATING MAY LEAD TO A SLIGHT CHC OF SHOWERS AND
TSTMS ACROSS THE HIGHER TERRAIN AND ALONG THE FRONT RANGE.
BY FRI THE ECMWF AND GFS WANT TO EJECT THE LOW FM SRN CALIFORNIA
INTO THE FOUR CORNERS AREA BY FRI AFTN WHILE THE CANADIAN MODEL IS
CONSIDERABLY SLOWER AND FUTHER SW. THIS FAR OUT HARD TO SAY WHAT
WILL HAPPEN WITH THIS NEXT FEATURE. FOR NOW WILL JUST GO WITH CHC
POPS IN THE MTNS WITH A SLIGHT CHC OVER THE PLAINS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 412 AM MDT SAT APR 23 2016
VFR CONDITIONS EXPECTED TO CONTINUE THROUGH TODAY AND TONIGHT.
SOUTH TO SOUTHWEST WINDS WILL BE INCREASING THROUGH THIS AFTERNOON
AS A SURFACE TROUGH DEEPENS OVER THE EASTERN PLAINS. GUSTS UP TO
30 MPH CAN BE EXPECTED BY LATE THIS AFTERNOON. CONVECTION IS
EXPECTED OVER THE FOOTHILLS THIS AFTERNOON WHICH COULD MOVE OUT
OVER THE URBAN CORRIDOR DURING THE EVENING AS THE MAIN UPPER
TROUGH PROGRESSES EASTWARD. GUSTY WINDS BUT LITTLE PRECIPITATION
IS EXPECTED FROM THE HIGH BASED SHOWERS. GUSTS UP TO 40 MPH WILL
BE POSSIBLE WITH THE EARLY EVENING SHOWER ACTIVITY.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...DANKERS
LONG TERM...RPK
AVIATION...DANKERS
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1020 PM EDT SUN APR 24 2016
.DISCUSSION...
A SMALL SURGE IN EASTERLY FLOW WILL COMBINE WITH SUFFICIENT LOW
LEVEL MOISTURE SEEN ON THE EVENING CAPE SOUNDING TO SUPPORT ISOLATED
SHOWERS/SPRINKLES OVER THE ATLC. A FEW OF THESE SHOULD CROSS THE
COAST OVERNIGHT AND EARLY MON MORNING AS INDICATED BY HRRR AND LOCAL
WRF MESOSCALE MODELS. MILD TEMPERATURES WITH LOWS IN THE MID 60S...
EXCEPT UPPER 60S/NR 70 ALG THE COAST DUE TO PERSISTENT ONSHORE FLOW.
&&
.AVIATION...VFR. SHALLOW SFC-BASED MOISTURE IN DVLPG E-ESE BLYR FLOW
REGIME SHOULD BE SUFFICIENT TO ALLOW DIURNAL CU/SC (FEW-SCT025-035)
NEAR THE COAST OVERNIGHT AND MON MORNING WITH A ISOLD -SHRA/--SHRA
POSSIBLE.
&&
.MARINE...
EAST WINDS HAVE INCREASED TO 15 KNOTS AND EXPECT SEAS TO RESPOND
OVERNIGHT BUILDING TO 3FT NEAR SHORE AND UP TO 4FT OFFSHORE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 66 80 63 82 / 0 10 10 10
MCO 66 84 64 85 / 10 10 10 10
MLB 68 80 66 81 / 10 10 10 10
VRB 67 81 64 81 / 0 10 10 10
LEE 65 84 65 85 / 10 20 10 10
SFB 64 83 64 85 / 10 10 10 10
ORL 67 84 65 85 / 10 10 10 10
FPR 67 81 63 81 / 10 10 10 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
KELLY/PENDERGRAST
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
946 AM EDT SAT APR 23 2016
.UPDATE...DRY CONDITIONS TODAY AS UPPER TROUGH AXIS MOVES
OFFSHORE...WITH MORNING SOUNDINGS SHOWING DRYING CONDITIONS IN
MID/UPR LEVELS. SATELLITE IMAGERY SHOWING WIDESPREAD LOW CLOUD
COVER...WHICH LATEST HRRR MODEL AND LAV GUIDANCE GRADUALLY
DECREASE IN COVERAGE THRU 17Z...AND HAVE UPDATED HOURLY GRIDS TO
REFLECT SLOW CLEARING AND DELAY IN HEATING. STILL EXPECT AFTERNOON
SUNSHINE PUSHING TEMPS UP INTO THE LOW 80S WITH MID 80S IN A FEW
LOCATIONS.
&&
.AVIATION...IFR CONDITIONS EXPECTED TO PERSIST THIS MORNING
BEFORE IMPROVING CONDITIONS MIDDAY...AND HAVE UPDATED TAFS TO
REFLECT THIS EXPECTATION. VFR CONDITIONS THIS AFTERNOON AND
TONIGHT.
&&
.MARINE...NO SIG CHANGES PLANNED IN NEXT CWF ISSUANCE. A FRONTAL
BOUNDARY WILL PUSH THROUGH THE REGION THIS MORNING...WITH WEST TO
NORTHWEST WINDS 10-15 KNOTS THIS MORNING. WINDS WILL BECOME LIGHT
IN THE AFTERNOON THROUGH MIDNIGHT TONIGHT. HIGH PRESSURE WILL
BUILD NORTH OF THE REGION...AND NORTHEASTERLY WINDS WILL INCREASE
LATE TONIGHT THROUGH SUNDAY TO 10-15 KNOTS. HIGH PRESSURE WILL
THEN SHIFT SLOWLY SOUTHEAST ACROSS THE WESTERN ATLANTIC THROUGH
THE MIDDLE OF THE WEEK...WITH WINDS VEERING TO THE SOUTHEAST
MONDAY AND SOUTHWEST BY THE MIDDLE OF THE WEEK. SEAS ARE FORECAST
TO BE GENERALLY IN THE 2-4 FEET RANGE THROUGH THE MIDDLE OF THE
WEEK...EXCEPT 3-5 FEET THIS MORNING BEYOND 20 NM OFFSHORE.
RIP CURRENTS: LOW RISK OF RIP CURRENTS THROUGH THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 82 57 83 59 / 10 0 0 0
SSI 80 64 75 65 / 10 0 0 10
JAX 82 59 80 63 / 10 0 10 10
SGJ 82 65 77 66 / 10 10 10 10
GNV 83 59 84 62 / 10 10 10 10
OCF 82 59 85 63 / 10 10 10 10
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
WOLF/SHASHY
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
438 AM EDT SAT APR 23 2016
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THIS MORNING. HIGH PRESSURE WILL PREVAIL
THROUGH LATE NEXT WEEK. A COLD FRONT WILL THEN APPROACH THE AREA EARLY
NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
PRE-DAWN...A COLD FRONT WILL BE APPROACHING THE FORECAST AREA DURING
THE NEXT FEW HOURS. PRIOR TO ITS ARRIVAL WILL BE WIDESPREAD LOW
CLOUDS DEVELOPING ALONG WITH PATCHY TO AREAS OF FOG AS STRATUS DECKS
ARE ALREADY RUNNING LOW ALONG AND WEST OF I-95. CANNOT RULE OUT
SOME LOCALLY DENSE FOG OVER INLAND ZONES BUT WIDESPREAD DENSE FOG
IS NOT LIKELY. A FEW SPRINKLES ARE POSSIBLE WITH SOME LIGHTER RAINS
BRUSHING THE IMMEDIATE COASTAL AREAS NORTH OF THE SAVANNAH RIVER.
TEMPS IN THE LOW TO MID 60S.
TODAY...A PRE-FRONTAL WIND SHIFT TO THE WEST WILL OCCUR NEW DAWN
WITH THE ACTUAL COLD FRONT PUSHING SOUTH THROUGH THE AREA DURING
THE LATE MORNING INTO THE EARLY AFTERNOON HOURS. STRONG DRYING
THROUGHOUT THE ATMOSPHERE SHOULD ENSURE A MAINLY DRY DAY FOR MOST
AS SURFACE DEW POINTS FALL INTO THE 50S BY MIDDAY AND CERTAINLY
DURING THE AFTERNOON. ONE POSSIBLE EXCEPTION WILL BE ALONG THE
COASTAL ZONES AS LINGERING MID LEVEL SHORTWAVE ENERGY COUPLED WITH
ENHANCED LOW-LEVEL CONVERGENCE ALONG A PINNED SEA BREEZE/COLD
FRONT INTERSECTION WILL SUPPORT A RISK FOR ISOLATED SHOWERS LATE
THIS MORNING INTO THE AFTERNOON...MAINLY ALONG AND EAST OF U.S.
17 IN SE SOUTH CAROLINA AND EAST OF I-95 IN COASTAL GEORGIA.
FORECAST SOUNDINGS SHOW GOOD MID LEVEL INSTABILITY BUT THE AIR
MASS LOOKS TOO DRY TO SUPPORT VIGOROUS UPDRAFTS ALOFT. FOR
PERSISTENCE WE MAINTAINED A MENTION OF ISOLATED TSTMS BUT WE THINK
THE POTENTIAL LOOKS PRETTY LOW AT THIS POINT. HIGHS WILL BE IN
THE LOWER 80S TODAY WITH SOME MID 80S CERTAINLY POSSIBLE.
TONIGHT...SKIES WILL CLEAR AS A SECONDARY BACKDOOR DRY FRONT MOVES
THROUGH THE REGION...TURNING LIGHT WINDS NNE OVERNIGHT WITH LOWS
DIPPING TO THE MID/UPPER 50S INLAND TO NEAR 60 COASTAL ZONES..
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
A FAIRLY QUIET AND DRY PERIOD IS EXPECTED EARLY NEXT WEEK AS HIGH
PRESSURE BUILDS FROM THE NORTH ON SUNDAY...THEN BECOMES MORE
ESTABLISHED OVER THE WESTERN ATLANTIC MONDAY AND TUESDAY. SFC HIGH
PRESSURE ALONG WITH DEEP LAYERED RIDGING ALOFT WILL SUPPORT OVERALL
HIGH TEMPS IN THE UPPER 70S TO LOWER 80S ON SUNDAY...THEN LOWER 80S
ON MONDAY. BY TUESDAY...A LIGHT SOUTHERLY FLOW AND ABUNDANT SUNSHINE
WILL SUPPORT SLIGHTLY WARMER TEMPS...WITH AFTERNOON HIGHS PEAKING IN
THE MID TO UPPER 80S FOR MOST LOCATIONS. OVERNIGHT LOWS WILL ALSO
SHOW A WARMING TREND EARLY NEXT WEEK. A LIGHT EAST/NORTHEAST WIND
AND CLEAR SKIES WILL SUPPORT SUNDAY NIGHT LOWS IN THE UPPER 50S
INLAND TO LOWER 60S ALONG THE COAST. MONDAY NIGHT LOWS WILL BE MORE
MILD AS WINDS BECOME DIRECTLY ONSHORE...WITH TEMPS RANGING IN THE
LOW TO MID 60S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
MOST AREAS WILL REMAIN DRY INTO THE MIDDLE OF NEXT WEEK AS A BROAD
MID/UPPER LVL RIDGE OF HIGH PRESSURE EXTENDS ACROSS THE SOUTHEASTERN
UNITED STATES. HOWEVER...WE CAN NOT RULE OUT A FEW SHOWERS AND/OR
THUNDERSTORMS WEDNESDAY AFTERNOON AND THURSDAY AFTERNOON AS WEAK MID
LVL WAVES OF ENERGY ROUND THE NORTHERN PERIPHERY OF THE RIDGE AND
PASS JUST TO OUR NORTH. A SLIGHT CHANCE OF SHOWERS WILL REMAIN IN
THE FORECAST ON WEDNESDAY...FOLLOWED BY A SLIGHT CHANCE OF
THUNDERSTORMS ON THURSDAY WHEN INSTABILITY IS HIGHER. BY FRIDAY...A
WEAK COLD FRONT WILL APPROACH THE AREA...PROMPTING ADDITIONAL SLIGHT
CHANCES OF SHOWERS AND/OR THUNDERSTORMS FRIDAY AFTERNOON. OVERALL
HIGH TEMPS WILL BE WARM DURING MID TO LATE WEEK...WITH AFTERNOON
HIGHS IN THE MID TO UPPER 80S. OVERNIGHT LOWS WILL ALSO BE MILD...IN
THE MID 60S.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
BOTH KCHS/KSAV WERE VFR AT 06Z INITIALIZATION TIME BUT LIFR
CIGS HAVE ALREADY MOVED INTO THE KSAV AIRPORT AND WHEN WINDS
DIMINISH IN A COUPLE OF HOURS WE WILL NEED TO WATCH FOR SOME
BUILD-DOWN DENSE FOG POTENTIAL. WHEN THE LOW LEVEL FLOWS TURNS
WEST OVERNIGHT...WE THINK SOME MVFR/IFR CIGS WILL ADVECT/DEVELOP
ALONG THE COASTAL CORRIDOR AROUND KCHS BUT OUR CONFIDENCE IS ONLY
FAIR GIVEN DIFFERENCES IN POINT SOUNDINGS FROM THE 13KM RAP AND
THE 00Z NAM MODELS. CONDITIONS SHOULD BECOME VFR BY MID TO LATE
MORNING AS CLOUDS MIX OUT IN LIGHT NW FLOW.
EXTENDED AVIATION OUTLOOK...VFR CONDITIONS ARE EXPECTED AT BOTH CHS
AND SAV TERMINALS.
&&
.MARINE...
TODAY...SOUTHWEST WINDS WILL OFFSHORE LATER THIS MORNING...THEN
TIP BACK TO SW FOR A WHILE THIS AFTERNOON. WIND SPEEDS SHOULD
MAINLY BE BELOW 15 KT AFTER SOME PRE-DAWN SURGES OVER OUTER
WATERS. A SECONDARY COLD FRONT WILL SLIDE SOUTH OVER THE WATERS
TONIGHT AND THERE WILL BE SOME SURGING NNE FLOW AFTER MIDNIGHT
THAT WILL WORK SOUTH TO THE GEORGIA WATERS BY DAWN ON SUNDAY.
THE SURGE COULD REACH 15-20 KT OFF THE CHARLESTON COAST WITH
SEAS BUILDING TO 4 FT LATE.
SUNDAY THROUGH THURSDAY...HIGH PRESSURE WILL CONTINUE TO BUILD FROM
THE NORTH ON SUNDAY...BEFORE BECOMING MORE ESTABLISHED OVER THE
COASTAL WATERS BY MONDAY. NORTHEAST WINDS WILL VEER AND BECOME MORE
ONSHORE AS THIS PROCESS UNFOLDS...BUT WILL REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS. SEAS WILL RANGE BETWEEN 2-4 FEET...HIGHEST BEYOND
10 NM FROM THE COAST. ATLANTIC HIGH PRESSURE WILL THEN DOMINATE THE
PATTERN TUESDAY THROUGH THURSDAY...WITH SOUTH/SOUTHWEST WINDS AT OR
BELOW 15 KT OVER THE COASTAL WATERS. SEAS WILL RANGE BETWEEN 1-3
FT...HIGHEST IN OFFSHORE GEORGIA WATERS.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...DPB
LONG TERM...DPB
AVIATION...DPB
MARINE...DPB
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
108 AM EDT SAT APR 23 2016
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH LATE TONIGHT AND PUSH OFFSHORE
SATURDAY MORNING. HIGH PRESSURE WILL PREVAIL THROUGH LATE NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
OVERNIGHT...A FEW LINGERING SHOWERS POSSIBLE THE REST OF THE
NIGHT UNTIL THE ACTUAL COLD FRONT MOVES THROUGH LATE. THE BEST
LIFT AND DEEPER MOISTURE WAS ON THE WAY OUT. WE MAINTAINED PATCHY
FOG TO THE FORECAST AFTER 2 OR 3 AM OVER THE CENTRAL SAVANNAH
RIVER AREA AND SITES SOUTH TO THE ALTAMAHA RIVER BASIN. THIS WILL
BE THE RESULT OF THE WET GROUNDS...LITTLE WIND FIELDS AND A
STRENGTHENING NOCTURNAL INVERSION. PLUS THERE IS THE POSSIBILITY
OF STRATUS BUILD-DOWN. FOG/STRATUS COULD CERTAINLY SPREAD FURTHER
NORTH/NE...BUT FOR NOW WE ARE SHOWING IT JUST WHERE THE LOWEST
CONDENSATION PRESSURE DEFICITS AND GEOSTROPHIC WINDS AT 1000 MB
ARE LESS THAN 10 KT. LOWS IN THE LOWER TO MID 60S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY/...
SATURDAY...A WIND PRE-FRONTAL WIND SHIFT TO THE WEST WILL OCCUR
AROUND SUNRISE WITH THE ACTUAL COLD FRONT PUSHING SOUTH THROUGH THE
AREA DURING THE LATE MORNING INTO THE EARLY AFTERNOON HOURS.
LINGERING 500 HPA SHORTWAVE ENERGY COUPLED WITH ENHANCED LOW-LEVEL
CONVERGENCE ALONG THE SEA BREEZE/COLD FRONT INTERSECTION WILL
SUPPORT A RISK FOR ISOLATED SHOWERS AND PERHAPS A TSTM FOR MUCH OF
THE DAY...MAINLY ACROSS THE CHARLESTON TRI-COUNTY AREA AND EXTENDING
SOUTH ALONG THE COAST INTO THE SAVANNAH METRO AREA. CAPPED POPS AT
20 PERCENT FOR NOW...BUT HIGHER POPS MAY EVENTUALLY BE NEEDED...
ESPECIALLY IN THE BEAUFORT-MCCLELLANVILLE AREA WHERE LOW-LEVEL
CONVERGENCE WILL BE THE STRONGEST. MODIFIED SOUNDINGS SHOW ENOUGH
INSTABILITY TO SUPPORT A MENTION OF TSTMS. HIGHS WILL GENERALLY TOP
OUT IN THE LOWER 80S AWAY FROM THE BEACHES. HIGH PRESSURE WILL BUILD
INTO THE AREA SATURDAY NIGHT AS THE COLD FRONT PUSHES FARTHER AWAY.
LOWS WILL RANGE FROM THE UPPER 50S INLAND TO THE LOWER-MID 60S AT
THE COAST...WARMEST ALONG THE GEORGIA BEACHES WHERE WINDS WILL TURN
ONSHORE AND HELP MODERATE CONDITIONS.
SUNDAY AND MONDAY...HIGH PRESSURE WILL EXTEND ACROSS THE AREA AS
DEEP LAYERED RIDGING BUILDS ALOFT. THIS WILL RESULT IN MOSTLY DRY
WEATHER WITH TEMPERATURES SLIGHTLY ABOVE NORMAL FOR LATE APRIL.
THERE ARE SIGNALS THAT A PUSH OF MOISTURE ASSOCIATED WITH THE
ONSHORE FLOW COULD SUPPORT ISOLATED SHOWERS AND POSSIBLY A TSTM OR
TWO SOUTH OF I-16 AHEAD OF THE SEA BREEZE MONDAY AFTERNOON. WILL GO
WITH A SLIGHT CHANCE OF SHOWERS/TSTMS THERE WITH RAIN-FREE
CONDITIONS ELSEWHERE. HIGHS WILL WARM INTO THE LOWER-MID 80S EACH
DAY AWAY FROM THE COAST WITH LOWS MONDAY MORNING DROPPING INTO THE
LOWER 60S INLAND WITH MID-UPPER 60S AT THE COAST...WARMEST ALONG THE
GEORGIA BEACHES.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MOST AREAS WILL REMAIN DRY INTO THE MIDDLE OF NEXT WEEK AS A BROAD
MID/UPPER LVL RIDGE OF HIGH PRESSURE EXTENDS ACROSS THE SOUTHEASTERN
UNITED STATES. HOWEVER...WE CAN NOT RULE OUT A FEW SHOWERS AND/OR
THUNDERSTORMS WEDNESDAY AND THURSDAY AFTERNOON AS SFC TEMPS PEAK IN
THE MID AND UPPER 80S AWAY FROM THE COAST. A SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS WILL REMAIN IN THE FORECAST...WITH
GREATEST CHANCES OCCURRING ALONG AN AFTERNOON SEABREEZE MOVING
INLAND. OVERNIGHT LOWS WILL BE MILD EACH NIGHT...IN THE LOW TO MID
60S.
&&
.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
BOTH KCHS/KSAV WERE VFR AT 06Z INITIALIZATION TIME BUT LOWER
CLOUDS WERE DEVELOPING UPSTREAM FROM BOTH TERMINALS. WHEN THE
LOW LEVEL FLOWS TURNS WEST OVERNIGHT...WE THINK SOME MVFR/IFR
CIGS WILL ADVECT/DEVELOP ALONG THE COASTAL CORRIDOR BUT OUR
CONFIDENCE IS ONLY FAIR GIVEN DIFFERENCES IN POINT SOUNDINGS
FROM THE 13KM RAP AND THE 00Z NAM MODELS. CONDITIONS SHOULD
BECOME VFR BY MID TO LATE MORNING AS CLOUDS MIX OUT IN LIGHT
NW FLOW.
EXTENDED AVIATION OUTLOOK...MAINLY VFR.
&&
.MARINE...
OVERNIGHT...ATLANTIC HIGH PRESSURE FAR OFF THE SE COAST IN THE
ATLANTIC WILL PULL FURTHER EAST AND GIVE WAY TO THE APPROACH OF A
COLD FRONT LATE. SW WINDS AS HIGH AS 15 OR PERHAPS 20 KT EARLY
WILL VEER TO MORE WEST AND DROP OFF 5 OR 10 KT LATE AS THE COLD
FRONT SLIDES IN BY DAYBREAK SATURDAY. SEAS WILL BEGIN THE NIGHT AT
3-5 FT...HIGHEST OVERT AMZ374 THEN SUBSIDE ABOUT A FOOT LATE AS
THE FLOW VEERS TO AN OFFSHORE DIRECTION. THE STRONGEST
T-STORMS HAVE ENDED FOR ALL BUT THE FAR NORTHERN PART OF AMZ350
EARLY ON.
SATURDAY...SOUTHWEST WINDS SATURDAY WILL TURN NORTH AND EVENTUALLY
NORTHEAST SATURDAY NIGHT AS A COLD FRONT PUSHES OFFSHORE AND HIGH
PRESSURE NOSES IN FROM THE NORTH. THE GRADIENT WILL BEGIN TO TIGHTEN
EARLY SUNDAY MORNING WITH SPEEDS POTENTIALLY REACHING AS HIGH AS 15
KT...ESPECIALLY ALONG THE LOWER SOUTH CAROLINA COASTAL WATERS...
OTHERWISE WINDS WILL REMAIN AROUND 10 KT OR SO WITH SEAS 2-3 FT
NEARSHORE...3-4 FT OFFSHORE...SUBSIDING TO 1-2 FT NEARSHORE...2-3 FT
OFFSHORE.
SUNDAY AND MONDAY...EAST TO NORTHEAST WINDS WILL PREVAIL WITH WINDS
GRADUALLY BECOMING MORE UNIFORMLY ONSHORE BY MONDAY. WINDS LOOK TO
REMAIN LESS THAN 15 KT WITH SEAS 1-2 FT NEARSHORE...2-3 FT OFFSHORE.
TUESDAY AND WEDNESDAY...WINDS WILL TURN MORE SOUTHERLY THROUGH THE
PERIOD AS HIGH PRESSURE SHIFTS OFFSHORE. LOCAL ENHANCEMENTS TO WIND
FIELD ARE LIKELY EACH AFTERNOON ALONG THE LAND/SEA INTERFACE AS THE
SEA BREEZE MOVES INLAND. SMALL CRAFT ADVISORY CONDITIONS ARE NOT
EXPECTED.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
1014 AM CDT SAT APR 23 2016
.SHORT TERM...
235 AM CDT
THROUGH SUNDAY
MOSTLY SUNNY SKIES ARE EXPECTED TODAY WITH SIGNIFICANT RANGE IN
TEMPS ACROSS THE AREA RANGING FROM LOWER 50S NEAR THE LAKE TO MID
TO UPPER 60S ONCE YOU GET 50+ MILES INLAND FROM THE LAKE.
SOUTHEAST WINDS WILL LOCK IN TONIGHT WITH WARM AIR ADVECTION
REGIME STARTING IN ADVANCE OF STRONG CYCLONE PROGGED TO MOVE OUT
INTO THE PLAINS TONIGHT. THIS SHOULD KEEP TEMPS FROM GETTING AS
COLD TONIGHT AS THEY ARE THIS MORNING...THOUGH MOST OF THE WARMING
TONIGHT WILL TAKE PLACE ALOFT. STRONGER SOUTHERLY WINDS WILL
DEVELOP SUNDAY AND ALLOW THE WARMTH ALOFT TO MIX TO THE SURFACE
WITH HIGHS LIKELY TOPPING OUT AROUND 80 DEGREES...EVEN ALONG THE
LAKE THANKS TO A STIFF SSW WIND.
IZZI
&&
.LONG TERM...
235 AM CDT
SUNDAY NIGHT THROUGH SATURDAY...
SHOWERS AND THUNDERSTORMS ARE LIKELY TO DEVELOP ALONG A COLD
FRONT FROM MN SOUTH ACROSS IA SOUTH INTO THE EASTERN PLAINS SUNDAY
AFTERNOON. THIS ACTIVITY WILL LIKELY DIMINISH SUNDAY NIGHT AS IT
ATTEMPTS TO MOVE EAST INTO A MORE CAPPED/LESS UNSTABLE AIR MASS
OVER OUR CWA...SO HAVE BACKED OFF ON POPS CONSIDERABLY. THE ECMWF
AND NAM WOULD BOTH FAVOR LITTLE OR NO PRECIP MAKING IT INTO OUR
AREA SUNDAY NIGHT. GUIDANCE HAS GENERALLY TRENDED TOWARD A
SOLUTION OF HANGING THE FRONT UP OVER WISCONSIN MONDAY KEEPING OUR
AREA IN THE BREEZY WARM SECTOR WITH ANOTHER UNSEASONABLY WARM AND
MOSTLY DRY DAY ON TAP. GFS CONTINUES TO PAINT PRECIP ACROSS THE
AREA MONDAY...BUT EVEN IT SHOWS A WEAKENING TREND AND LIKELY IS
OVERDONE WITH LIGHT QPF WITH BOTH ECMWF AND NAM SUGGESTING A
MAINLY DRY DAY. HAVE BACKED OFF ON POPS MONDAY AS A NOD TO THE
EC/NAM SOLUTION...BUT MAINTAINED SOME HIGH END CHANCE POPS DURING
THE AFTERNOON NORTHERN CWA LARGELY TO AVOID DRASTIC CHANGES TO THE
FORECAST.
AS THE WEAKENING SURFACE LOW PASSES ACROSS THE AREA MONDAY
EVENING THE SOUTHERLY FLOW THAT HAD BEEN HOLDING THE LAKE ENHANCED
FRONT TO OUR NORTH WILL COLLAPSE AND SHOULD ALLOW A VERY
IMPRESSIVE BACK DOOR PNEUMONIA FRONT TO COME BARRELING INTO
NE IL WITH A DRAMATIC DROP IN TEMPS MONDAY EVENING...PERHAPS ON
THE ORDER OF 20F+ DEGREES IN A MATTER OF MINUTES. COULD SEE SOME
SCATTERED SHOWERS AND T-STORMS MONDAY EVENING WITH THE FRONT...BUT
GIVEN THE DAMPENING SHORTWAVE ALOFT AND WEAKENING CONVERGENCE KEPT
POPS MODEST AS RAIN DOESNT APPEAR TO BE A SURE THING BY ANY MEANS
AT THIS DISTANCE.
LAKE ENHANCED COOL DOWN EXPECTED TUESDAY WITH DRY CONDITIONS. NEXT
STRONG SHORTWAVE EMANATING FROM THE WESTERN TROUGH IS PROGGED TO
MOVE INTO THE REGION TOWARD MID WEEK. MEDIUM RANGE MODELS FORECAST
THIS WAVE TO BE CLOSED OFF IN THE MID LEVELS AND WOULDNT BE
SURPRISED TO SEE LATER RUNS SLOW THE ARRIVAL OF PRECIP WITH THIS
SYSTEM. REGARDLESS...IT DOES LOOK LIKE A WET PERIOD AS THIS WAVE
MOVES ACROSS THE AREA WED/THUR TIME FRAME. CURRENT INDICATIONS ARE
THE SURFACE FRONT WILL HANG UP TO OUR SOUTH KEEPING MOST OF THE
AREA IN THE COOL SIDE OF THE SYSTEM AND WINDS OFF THE LAKE LOCKED
IN THROUGH THE REST OF THE WORK WEEK KEEPING TEMPS LAKESIDE
CHILLY.
IZZI
&&
.AVIATION...
UPDATED FOR THE 15Z TAFS...
STRATUS CLOUDS CONTINUE TO ERODE...AND EXPECT NEARLY SKC TO ARRIVE
ACROSS ALL AIRFIELDS BY 16Z OR SHORTLY AFTER.
FOR THE 12Z TAFS...
HIGH PRESSURE WILL RESULT IN LIGHT NORTHEAST TO EAST WINDS. WIND
SPEEDS SHOULD REMAIN BELOW 10 KT. SCT-BKN MVFR STRATUS HAS PUSHED
ONSHORE AND REACHED THE TERMINALS. EXPECTING THE STRATUS TO
SCATTER OUT LATE THIS MORNING. SKIES CLEAR AND WINDS BECOME SE
THIS EVENING. WINDS CONTINUE TO VEER TO SOUTH INTO SUNDAY MORNING
WITH INCREASING VFR CLOUDS AHEAD OF THE NEXT SYSTEM. WINDS ALSO
PICK UP SUNDAY MORNING WITH GUSTS BTWN 20-25 KT.
JEE
&&
.MARINE...
221 AM CDT
HEADLINES...WILL LET THE SMALL CRAFT ADVISORY EXPIRE THIS MORNING.
GUSTS MAY APPROACH 25 KT SUNDAY...BUT IT LOOKS LIKE A MARGINAL EVENT
AND HAVE LIMITED CONFIDENCE IN GUSTS 25+ KT. THEREFORE WILL NOT
ISSUE ANOTHER SMALL CRAFT ADVISORY AT THIS TIME.
HIGH PRESSURE OVERHEAD CONTINUES EAST THROUGH SUNDAY. LIGHT AND
VARIABLE WINDS BECOME SOUTHEAST TONIGHT. THE NEXT LOW FORMS OVER THE
PLAINS TONIGHT AND SHIFTS EAST PASSING OVER THE FAR SOUTHERN END OF
THE LAKE OR JUST SOUTH OF THE LAKE MONDAY NIGHT. WINDS BECOME
NORTHEAST TO EAST OVER THE NORTHERN END OF THE LAKE SUNDAY NIGHT AND
MAY INCREASE TO GALE FORCE GUSTS LATE SUNDAY NIGHT INTO MONDAY. WILL
INCLUDE OCNL GALE FORCE GUSTS IN THE GLF...BUT DO NOT HAVE ENOUGH
CONFIDENCE TO ISSUE A GALE WATCH AT THIS TIME. THE SOUTHERN TWO
THIRDS OF THE LAKE WILL SEE SOUTH WINDS TO 25 KT.
A COLD FRONT AHEAD OF HIGH PRESSURE OVER CANADA SINKS SOUTH DOWN THE
LAKE MONDAY NIGHT INTO TUESDAY. WINDS BECOME NORTHEAST BEHIND THE
FRONT AND REMAIN EAST TO NORTHEAST TO 25 KT THROUGH THURSDAY.
ANOTHER LOW PASSES OVER THE LAKE LATE NEXT WEEK. GUIDANCE DIFFERS ON
THE LOW/S PATH AND SPEED...BUT THEY DO AGREE ON HIGH PRESSURE MOVING
IN BEHIND THE LOW.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
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Area Forecast Discussion
National Weather Service Lincoln IL
1011 AM CDT SAT APR 23 2016
.UPDATE...
Issued at 1011 AM CDT Sat Apr 23 2016
Surface Ridge now traversing Illinois with light winds. Stratus
and patchy fog continue to move westward across southeast and
portions of east central Illinois. Expect the edges to begin to
erode as more insolation comes into play and dry air mixes down.
Though models may be dispersing the moisture a little fast given
the strength of the inversion evident in 12z KILX Sounding. Have
made some adjustments to delay clearing and lower high
temperatures in areas that currently have deepest boundary layer
moisture.
A mid deck moving eastward from Iowa may impact KGBG, but it is
moving into very dry air and should dissipate.
&&
.SHORT TERM...(Today)
ISSUED AT 321 AM CDT Sat Apr 23 2016
High pressure centered to our north today will bring pleasant
weather conditions to most of the area. However, a band of lower
clouds over parts of eastern Illinois early this morning was
drifting south-southwest and looks to affect, at least through
the morning hours, our east and southeast areas. As a result, with
the cloud cover expected to hold on into at least the early
afternoon hours, temperatures will be tapered back a bit from
guidance with the cooler afternoon highs (mid to upper 60s) over
the east and especially far southeast counties. while out west,
with full sunshine, we look for afternoon highs in the low to
possibly mid 70s.
.LONG TERM...(Tonight through Friday)
ISSUED AT 321 AM CDT Sat Apr 23 2016
500mb ridge building into the Midwest for the first part of the
weekend will keep the mild weather in place through tonight and into
tomorrow for Central Illinois. After a Sunday with high temps
approaching 80F and increasing southerly winds, the next system will
bring rain chances back to the forecast Sunday night. The overall
shift in the long waves puts the Midwest into an active weather next
week. Some timing differences for the next system Sunday
night...with the GFS the earliest with the onset of rain NW of the
Illinois River Valley before midnight. ECMWF and NAM dry before 12z
Monday morning. NAM actually driest in the bunch for Monday with
very little in the way of QPF, even though it similarly develops the
warm frontal boundary to the north, keeping much of the region in
the warm sector. NAM responds with precip, but delays the more
widespread QPF until the cold front moves through on Monday night.
Forecast will keep the chance mentions Mon-Tue for that round...with
some clearing possible later on Tuesday. But any clearing will be
short lived as a deep low out of the SW develops its surface system
over the southern Plains, driving WAA into the Midwest with a
developing warm front/precip on Tuesday night. Forecast looking wet
through the middle of the week through Thursday with the eventual
passage of the associated sfc low and cold front. Unfortunately, the
larger scale shift to a more progressive and active weather pattern
also means that the break between systems is short, and the next
weekend is also starting to look potentially wet.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
Issued at 600 AM CDT Sat Apr 23 2016
VFR conditions expected over PIA and SPI with some MVFR cigs
possible this morning into the early afternoon hours at CMI
BMI and DEC. Latest satellite data and surface obs continue
to indicate a band of mostly MVFR cigs was located from just
east of CMI and tracking southwest. Latest RAP forecast
soundings indicate the higher probabilities for cigs from
1200-2000 feet AGL would be at CMI to just east of DEC with
BMI more few-sct at 1200 feet. These clouds are expected to
slowly fade as we move into the afternoon hours with more
scattered clouds after 19z in our eastern TAF sites. Surface
winds today will become easterly at 5 to 10 kts and southeast
at 5 to 10 kts tonight.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Barker
SHORT TERM...Smith
LONG TERM...HJS
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
632 AM CDT SAT APR 23 2016
.SHORT TERM...
235 AM CDT
THROUGH SUNDAY
MOSTLY SUNNY SKIES ARE EXPECTED TODAY WITH SIGNIFICANT RANGE IN
TEMPS ACROSS THE AREA RANGING FROM LOWER 50S NEAR THE LAKE TO MID
TO UPPER 60S ONCE YOU GET 50+ MILES INLAND FROM THE LAKE.
SOUTHEAST WINDS WILL LOCK IN TONIGHT WITH WARM AIR ADVECTION
REGIME STARTING IN ADVANCE OF STRONG CYCLONE PROGGED TO MOVE OUT
INTO THE PLAINS TONIGHT. THIS SHOULD KEEP TEMPS FROM GETTING AS
COLD TONIGHT AS THEY ARE THIS MORNING...THOUGH MOST OF THE WARMING
TONIGHT WILL TAKE PLACE ALOFT. STRONGER SOUTHERLY WINDS WILL
DEVELOP SUNDAY AND ALLOW THE WARMTH ALOFT TO MIX TO THE SURFACE
WITH HIGHS LIKELY TOPPING OUT AROUND 80 DEGREES...EVEN ALONG THE
LAKE THANKS TO A STIFF SSW WIND.
IZZI
&&
.LONG TERM...
235 AM CDT
SUNDAY NIGHT THROUGH SATURDAY...
SHOWERS AND THUNDERSTORMS ARE LIKELY TO DEVELOP ALONG A COLD
FRONT FROM MN SOUTH ACROSS IA SOUTH INTO THE EASTERN PLAINS SUNDAY
AFTERNOON. THIS ACTIVITY WILL LIKELY DIMINISH SUNDAY NIGHT AS IT
ATTEMPTS TO MOVE EAST INTO A MORE CAPPED/LESS UNSTABLE AIR MASS
OVER OUR CWA...SO HAVE BACKED OFF ON POPS CONSIDERABLY. THE ECMWF
AND NAM WOULD BOTH FAVOR LITTLE OR NO PRECIP MAKING IT INTO OUR
AREA SUNDAY NIGHT. GUIDANCE HAS GENERALLY TRENDED TOWARD A
SOLUTION OF HANGING THE FRONT UP OVER WISCONSIN MONDAY KEEPING OUR
AREA IN THE BREEZY WARM SECTOR WITH ANOTHER UNSEASONABLY WARM AND
MOSTLY DRY DAY ON TAP. GFS CONTINUES TO PAINT PRECIP ACROSS THE
AREA MONDAY...BUT EVEN IT SHOWS A WEAKENING TREND AND LIKELY IS
OVERDONE WITH LIGHT QPF WITH BOTH ECMWF AND NAM SUGGESTING A
MAINLY DRY DAY. HAVE BACKED OFF ON POPS MONDAY AS A NOD TO THE
EC/NAM SOLUTION...BUT MAINTAINED SOME HIGH END CHANCE POPS DURING
THE AFTERNOON NORTHERN CWA LARGELY TO AVOID DRASTIC CHANGES TO THE
FORECAST.
AS THE WEAKENING SURFACE LOW PASSES ACROSS THE AREA MONDAY
EVENING THE SOUTHERLY FLOW THAT HAD BEEN HOLDING THE LAKE ENHANCED
FRONT TO OUR NORTH WILL COLLAPSE AND SHOULD ALLOW A VERY
IMPRESSIVE BACK DOOR PNEUMONIA FRONT TO COME BARRELING INTO
NE IL WITH A DRAMATIC DROP IN TEMPS MONDAY EVENING...PERHAPS ON
THE ORDER OF 20F+ DEGREES IN A MATTER OF MINUTES. COULD SEE SOME
SCATTERED SHOWERS AND T-STORMS MONDAY EVENING WITH THE FRONT...BUT
GIVEN THE DAMPENING SHORTWAVE ALOFT AND WEAKENING CONVERGENCE KEPT
POPS MODEST AS RAIN DOESNT APPEAR TO BE A SURE THING BY ANY MEANS
AT THIS DISTANCE.
LAKE ENHANCED COOL DOWN EXPECTED TUESDAY WITH DRY CONDITIONS. NEXT
STRONG SHORTWAVE EMANATING FROM THE WESTERN TROUGH IS PROGGED TO
MOVE INTO THE REGION TOWARD MID WEEK. MEDIUM RANGE MODELS FORECAST
THIS WAVE TO BE CLOSED OFF IN THE MID LEVELS AND WOULDNT BE
SURPRISED TO SEE LATER RUNS SLOW THE ARRIVAL OF PRECIP WITH THIS
SYSTEM. REGARDLESS...IT DOES LOOK LIKE A WET PERIOD AS THIS WAVE
MOVES ACROSS THE AREA WED/THUR TIME FRAME. CURRENT INDICATIONS ARE
THE SURFACE FRONT WILL HANG UP TO OUR SOUTH KEEPING MOST OF THE
AREA IN THE COOL SIDE OF THE SYSTEM AND WINDS OFF THE LAKE LOCKED
IN THROUGH THE REST OF THE WORK WEEK KEEPING TEMPS LAKESIDE
CHILLY.
IZZI
&&
.AVIATION...
FOR THE 12Z TAFS...
HIGH PRESSURE WILL RESULT IN LIGHT NORTHEAST TO EAST WINDS. WIND
SPEEDS SHOULD REMAIN BELOW 10 KT. SCT-BKN MVFR STRATUS HAS PUSHED
ONSHORE AND REACHED THE TERMINALS. EXPECTING THE STRATUS TO
SCATTER OUT LATE THIS MORNING. SKIES CLEAR AND WINDS BECOME SE
THIS EVENING. WINDS CONTINUE TO VEER TO SOUTH INTO SUNDAY MORNING
WITH INCREASING VFR CLOUDS AHEAD OF THE NEXT SYSTEM. WINDS ALSO
PICK UP SUNDAY MORNING WITH GUSTS BTWN 20-25 KT.
JEE
&&
.MARINE...
221 AM CDT
HEADLINES...WILL LET THE SMALL CRAFT ADVISORY EXPIRE THIS MORNING.
GUSTS MAY APPROACH 25 KT SUNDAY...BUT IT LOOKS LIKE A MARGINAL EVENT
AND HAVE LIMITED CONFIDENCE IN GUSTS 25+ KT. THEREFORE WILL NOT
ISSUE ANOTHER SMALL CRAFT ADVISORY AT THIS TIME.
HIGH PRESSURE OVERHEAD CONTINUES EAST THROUGH SUNDAY. LIGHT AND
VARIABLE WINDS BECOME SOUTHEAST TONIGHT. THE NEXT LOW FORMS OVER THE
PLAINS TONIGHT AND SHIFTS EAST PASSING OVER THE FAR SOUTHERN END OF
THE LAKE OR JUST SOUTH OF THE LAKE MONDAY NIGHT. WINDS BECOME
NORTHEAST TO EAST OVER THE NORTHERN END OF THE LAKE SUNDAY NIGHT AND
MAY INCREASE TO GALE FORCE GUSTS LATE SUNDAY NIGHT INTO MONDAY. WILL
INCLUDE OCNL GALE FORCE GUSTS IN THE GLF...BUT DO NOT HAVE ENOUGH
CONFIDENCE TO ISSUE A GALE WATCH AT THIS TIME. THE SOUTHERN TWO
THIRDS OF THE LAKE WILL SEE SOUTH WINDS TO 25 KT.
A COLD FRONT AHEAD OF HIGH PRESSURE OVER CANADA SINKS SOUTH DOWN THE
LAKE MONDAY NIGHT INTO TUESDAY. WINDS BECOME NORTHEAST BEHIND THE
FRONT AND REMAIN EAST TO NORTHEAST TO 25 KT THROUGH THURSDAY.
ANOTHER LOW PASSES OVER THE LAKE LATE NEXT WEEK. GUIDANCE DIFFERS ON
THE LOW/S PATH AND SPEED...BUT THEY DO AGREE ON HIGH PRESSURE MOVING
IN BEHIND THE LOW.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FROST ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006 UNTIL 8 AM SATURDAY.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
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Area Forecast Discussion
National Weather Service Lincoln IL
606 AM CDT SAT APR 23 2016
.SHORT TERM...(Today)
ISSUED AT 321 AM CDT Sat Apr 23 2016
High pressure centered to our north today will bring pleasant
weather conditions to most of the area. However, a band of lower
clouds over parts of eastern Illinois early this morning was
drifting south-southwest and looks to affect, at least through
the morning hours, our east and southeast areas. As a result, with
the cloud cover expected to hold on into at least the early
afternoon hours, temperatures will be tapered back a bit from
guidance with the cooler afternoon highs (mid to upper 60s) over
the east and especially far southeast counties. while out west,
with full sunshine, we look for afternoon highs in the low to
possibly mid 70s.
.LONG TERM...(Tonight through Friday)
ISSUED AT 321 AM CDT Sat Apr 23 2016
500mb ridge building into the Midwest for the first part of the
weekend will keep the mild weather in place through tonight and into
tomorrow for Central Illinois. After a Sunday with high temps
approaching 80F and increasing southerly winds, the next system will
bring rain chances back to the forecast Sunday night. The overall
shift in the long waves puts the Midwest into an active weather next
week. Some timing differences for the next system Sunday
night...with the GFS the earliest with the onset of rain NW of the
Illinois River Valley before midnight. ECMWF and NAM dry before 12z
Monday morning. NAM actually driest in the bunch for Monday with
very little in the way of QPF, even though it similarly develops the
warm frontal boundary to the north, keeping much of the region in
the warm sector. NAM responds with precip, but delays the more
widespread QPF until the cold front moves through on Monday night.
Forecast will keep the chance mentions Mon-Tue for that round...with
some clearing possible later on Tuesday. But any clearing will be
short lived as a deep low out of the SW develops its surface system
over the southern Plains, driving WAA into the Midwest with a
developing warm front/precip on Tuesday night. Forecast looking wet
through the middle of the week through Thursday with the eventual
passage of the associated sfc low and cold front. Unfortunately, the
larger scale shift to a more progressive and active weather pattern
also means that the break between systems is short, and the next
weekend is also starting to look potentially wet.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
Issued at 600 AM CDT Sat Apr 23 2016
VFR conditions expected over PIA and SPI with some MVFR cigs
possible this morning into the early afternoon hours at CMI
BMI and DEC. Latest satellite data and surface obs continue
to indicate a band of mostly MVFR cigs was located from just
east of CMI and tracking southwest. Latest RAP forecast
soundings indicate the higher probabilities for cigs from
1200-2000 feet AGL would be at CMI to just east of DEC with
BMI more few-sct at 1200 feet. These clouds are expected to
slowly fade as we move into the afternoon hours with more
scattered clouds after 19z in our eastern TAF sites. Surface
winds today will become easterly at 5 to 10 kts and southeast
at 5 to 10 kts tonight.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Smith
LONG TERM...HJS
AVIATION...Smith
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
156 PM EDT SAT APR 23 2016
.UPDATE...
ISSUED AT 156 PM EDT SAT APR 23 2016
ADJUSTED THE SKY COVER...TEMPERATURES...AND DEW POINTS OVER THE
NEXT SEVERAL HOURS. CLEARING HAS BEEN WORKING IN FROM THE NORTH
MORE AGRESSIVELY IN THE PAST COUPLE OF HOURS. MADE A FEW TWEAKS TO
THE HIGH TEMPERATURES BASED ON THE LATEST TRENDS...BUT THE MAIN
ADJUSTMENTS WERE RETARDING THE DIURNAL CLIMB A BIT MORE OVER THE
NEXT 1 TO 2 HOURS...BEFORE A LATE DAY COMEBACK ENSUES ONCE THE
BETTER CLEARING TAKES PLACE.
UPDATE ISSUED AT 1041 AM EDT SAT APR 23 2016
THE UPPER LEVEL TROUGH AXIS CONTINUES TO SHIFT OFF TO THE
EAST...WITH HEIGHTS RECOVERING THE REST OF THE DAY. SPRINKLES/VERY
LIGHT RAIN SHOWERS HAVE EXITED OUR FAR SOUTHEAST...BUT CLOUDS
LOOK TO HANG TOUGH TODAY AND MODELS ARE A BIT OPTIMISTIC WITH THE
CLEARING COMPARED TO THE VISIBLE SATELLITE TRENDS. GIVEN THE LOW
LEVEL NORTH TO NORTHEAST FLOW AND MAINLY NEUTRAL ADVECTION AT 850
MB...HAVE ALLOWED THE CLOUDS TO HANG ON LONGER. CONSEQUENTLY...
TEMPERATURES ARE ALSO RUNNING A BIT COOLER...SO HAVE LOWERED THE
HIGHS SOMEWHAT...MAINLY LOW TO MID 60S FOR MOST EAST OF
I-75...WITH UPPER 60S TO AROUND 70 WEST OF I-75...WHERE CLEARING
WILL TAKE PLACE THE QUICKEST. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 736 AM EDT SAT APR 23 2016
RADAR CONTINUES TO SHOW LIGHT RETURNS ACROSS THE HIGHER TERRAIN
WHERE LOW LEVELS REMAIN SATURATED BENEATH A LOW STRATUS DECK. HAVE
THEREFORE INSERTED SPRINKLES THROUGH MID MORNING AS NOTHING MORE
THAN A TRACE OF PRECIPITATION SHOULD BE POSSIBLE. REDUCED
VISIBILITIES ALSO OCCURRING IN SPOTS...BUT BLANKET OF LOW CLOUDS
SHOULD NEGATE ANY THREAT FOR WIDESPREAD DENSE FOG.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 338 AM EDT SAT APR 23 2016
UPPER TROUGH CURRENTLY PUSHING EAST ACROSS WEST VIRGINIA WILL
BRING DEEP LAYER SUBSIDENCE TO EASTERN KENTUCKY...LEADING TO
GRADUALLY CLEARING SKIES LATER THIS MORNING. BEFORE THEN...A BATCH
OF LOW STRATUS WILL CONTINUE TO PROPAGATE SOUTH ACROSS THE OHIO
VALLEY AND INTO THE COMMONWEALTH AHEAD OF A SURFACE RIDGE BUILDING
ACROSS THE GREAT LAKES AS LOW LEVELS REMAIN RATHER MOIST. THIS
SHOULD KEEP FOG PATCHY IN NATURE AS RADIATIONAL COOLING WILL BE
IMPEDED BY THE INCOMING CLOUD DECK. HOWEVER...NOT EXPECTING ANY
ADDITIONAL RAINFALL WITH UPPER SUPPORT OFF TO THE EAST AND DRYING
MID-UPPER LEVELS.
WILL SEE ALL FOG MIX OUT BY MID-LATE MORNING AS DRIER AIR
CONTINUES TO BUILD TOWARD THE SURFACE. CLOUD COVER WILL ERODE WITH
SKIES CLEARING OUT BY LATER THIS AFTERNOON INTO TONIGHT. LIGHT
NORTHERLY WINDS WILL BRING SUBTLE COOL AIR ADVECTION AND ACT TO
HOLD HIGH TEMPERATURES THIS AFTERNOON IN THE MID 60S TO LOW 70S.
SURFACE HIGH PRESSURE MIGRATING ACROSS THE EASTERN GREAT LAKES
INTO THE APPALACHIANS WILL KEEP SKIES CLEAR TONIGHT AND WINDS
LIGHT. GIVEN RECENT PRECIPITATION FRIDAY...AT LEAST PATCHY VALLEY
FOG SHOULD BE A CERTAINTY AS AN APPRECIABLE RIDGE/VALLEY SPLIT
DEVELOPS. EXPECT A FEW OF THE MORE SHELTERED VALLEY LOCALES TO
DROP INTO THE UPPER 30S WITH MOST RIDGE LOCATIONS GENERALLY IN THE
LOW-MID 40S.
BUILDING HEIGHTS ALOFT AND VEERING SOUTHERLY WINDS WILL LEAD TO A
NOTICEABLE WARMUP FOR SUNDAY AS TEMPERATURES TOP OUT IN THE UPPER
70S TO LOWER 80S.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 338 AM EDT SAT APR 23 2016
OUR WEATHER SHOULD BE MORE ACTIVE NEXT WEEK AS SHORTWAVES EJECT
OUT OF A WESTERN CONUS THROUGH AND TRACK JUST TO OUR WEST INTO THE
UPPER MIDWEST AND GREAT LAKES REGION. AT THE SURFACE...A FRONTAL
BOUNDARY WILL DROP INTO THE REGION BY TUESDAY AND HANG AROUND
THROUGH MIDWEEK. A LOW PRESSURE SYSTEM WILL ALSO GET ORGANIZED
OVER THE PLAINS MIDWEEK. THIS SYSTEM WILL TRACK EASTWARD SENDING A
COLD FRONT TOWARD OUR REGION LATE IN THE WORK WEEK.
SENSIBLE WEATHER WILL FEATURE A NICE WARM MONDAY WITH PLENTY OF
SUNSHINE AND HIGHS IN THE LOW TO MID 80S. THE THREAT FOR SHOWERS
AND THUNDERSTORMS WILL THEN INCREASE FROM NORTH TO SOUTH LATE
MONDAY NIGHT INTO TUESDAY AS THE FRONT DROPS SOUTH INTO THE
REGION. JUST SCATTERED SHOWERS/STORMS ARE ANTICIPATED TUESDAY AND
WEDNESDAY AS THE FRONT IS NOT PARTICULARLY STRONG OR EQUIPPED WITH
MUCH MOISTURE. OUR BEST CHANCE FOR SHOWERS/STORMS APPEARS TO BE
WEDNESDAY NIGHT INTO THE DAY ON THURSDAY AS THE COLD FRONT ENTERS
THE SCENE FROM THE WEST. LESSER RAIN CHANCES ARE FORECAST FOR
FRIDAY...BUT CANNOT REMOVE THEM TOTALLY WITH THE FRONT AND
ACCOMPANYING LOW PRESSURE SYSTEM REMAINING NEARBY PER THE GFS AND
ECMWF.
DESPITE THE DAILY CHANCE OF RAIN TUESDAY THROUGH FRIDAY...A
WIDESPREAD SOAKING RAINFALL APPEARS UNLIKELY AT THIS TIME.
ALSO...DESPITE THE FRONTAL PASSAGE LATE IN THE WEEK...TEMPS WILL
REMAIN WELL ABOVE NORMAL...ONLY DROPPING FROM THE LOW TO MID 80S
TUESDAY THROUGH THURSDAY TO THE MID TO UPPER 70S ON FRIDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 156 PM EDT SAT APR 23 2016
IFR/MVFR STRATOCU WILL GRADUALLY RAISE AND SCATTER OUT THROUGH
22Z...WITH SJS HANGING ON TO THE LOWER CEILINGS THE LONGEST.
CLEARING WILL REIGN TONIGHT...HOWEVER AS WINDS LIGHTEN UP AND LOW
LEVEL MOISTURE REMAINS...SOME VALLEY FOG WILL LIKELY
FORM...ESPECIALLY ALONG AND SOUTH OF THE HAL ROGERS PARKWAY AND
HIGHWAY 80 CORRIDORS. AS SUCH...DID CARRY A SMALL WINDOW OF MVFR
VISIBILITIES AT LOZ AND SME...AND IFR AT SJS. VFR CONDITIONS WILL
RETURN BETWEEN 12 AND 14Z. NORTH TO NORTHEAST WINDS OF 5 TO 10
KTS WILL BECCOME LIGHT AND VARIABLE AFTER DUSK.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...GUSEMAN
LONG TERM...ABE
AVIATION...GEOGERIAN
Area Forecast Discussion
National Weather Service Paducah KY
1234 PM CDT SAT APR 23 2016
.UPDATE...
Issued at 1231 PM CDT Sat Apr 23 2016
The AVIATION section has been updated for the 18Z TAF issuance.
&&
UPDATE Issued at 939 AM CDT Sat Apr 23 2016
Updated for Today due to clouds. Pesky thin layer of low clouds
will remain through much of the morning before mostly dissipating
by early afternoon. Have adjusted today`s max temps down a degree
or two in the central and eastern parts of the FA where cloud
cover is extensive this morning.
&&
.SHORT TERM...(Today through Monday night)
Issued at 304 AM CDT Sat Apr 23 2016
The main issue early this morning is surface high pressure surging
southwest into the region. It is keeping the northeast winds
stirred up and ushering in a solid layer of IFR level clouds that
guidance does not have a good handle on. The clouds now cover much
of the Evansville Tri State, and should continue to push
southward, per the RAP low-level RH forecast, toward the Lakes and
Pennyrile. Figure that the low clouds will dissipate quickly this
morning by 15Z.
The clouds will have more of an impact on aviation concerns, and
the AVIATION of this discussion has been updated as well.
Temperatures may be held up just a bit under the cloud cover
through daybreak, but not much, and they may hold down highs a
degree or two in the east. With plenty of sunshine expected this
afternoon and dry air in place over the region, this forecast still
leaned toward the warmer side of the guidance envelope for highs.
Surface high pressure will continue to dominate the region tonight,
so clear skies and light winds will allow for good radiational
cooling. Definitely went at or below coolest guidance for tonight`s
lows in most locations. The surface high will push east of the
area on Sunday, allowing south winds to return across the region.
With high pressure aloft resulting in mostly sunny skies, went at
or above the warmest guidance. Most of the area should be in the
lower 80s.
South winds will stay up in the 5 to 10 mph range Sunday night, so
it should be a milder night. Skies will still be no worse than
partly cloudy, so will not go much above guidance. Lows should be
around 60.
As our next potential storm system settles over the Four Corners
region Monday, the flow aloft over our region will become nearly
zonal. A surface cold front will become strung out nearly west to
east well to our north. This should keep us high and dry Monday
and most likely Monday night, too. Will have the slightest of PoPs
for SHRA/TSRA in the Perryville, Pinckneyville, and Mt Vernon
areas on Monday and along the I-64 corridor Monday night, but this
is mainly just to provide a buffer with our surrounding forecast
areas.
The 00Z models do not indicate much increase in clouds Monday, so
temperatures should soar into the 80-85F range, which is well above
guidance. Lows Monday night will continue to trend milder. With a
bit more wind expected, and increasing clouds overnight, lows will
be in the 60-65F range.
.LONG TERM...(Tuesday through Friday)
Issued at 304 AM CDT Sat Apr 23 2016
The upper-level split flow pattern will consist of an active
southern stream across the United States, and a more diffuse polar
jet across northern Canada. A series of shortwaves will eject
northeast out of the Desert Southwest to the central Plains, then
finally into the Great Lakes before weakening. There are still
significant model differences concerning the timing of these
shortwaves and their associated frontal systems. Overall, the
pattern looks rather warm and wet given the storm track to our
north.
As far as the daily specifics, the models are in good agreement for
Tuesday. A narrow 500 mb ridge will pass over the Mississippi Valley
ahead of the first shortwave, which will be emerging into the
southern high Plains. Beneath the ridge aloft, the models continue
to sag a weak frontal boundary south to Interstate 64 by late in the
day Tuesday. The air mass is forecast to be warm and unstable south
of the front, moreso than with other fronts this spring. Therefore,
chance pops will be kept in the forecast despite weak forcing aloft.
The weak frontal boundary should continue south into the Lower Ohio
Valley Tuesday night. Beyond that, the models really start to
diverge on the timing of subsequent frontal passages. The front may
move south of our area before returning north as a warm front during
the middle of the week. A weakening surface low will then move east
across the Midwest Wednesday night and Thursday. A cold front
trailing southwest from the low will move across our region, but
timing differences are quite large. The faster 00z ecmwf is
consistent with the previous NWS forecast and the 12z Fri ecmwf
ensemble mean. However, the slower 00z gfs has support from the
00z gefs. In a nutshell, pops will be in the high chance to likely
category Wed and Wednesday night. Compared with previous systems
this spring, there will be plenty of moisture and instability for
convection. Wind profiles will be moderately strong. A few intense
storms are possible.
Late in the week, another weak shortwave ridge will traverse the
Mississippi and Ohio Valleys between systems. The weak cold front
will be suppressed south of our region. It now appears Friday will
be dry in many areas, but a slight chance pop will be retained
closer to the frontal boundary in the Tennessee border counties
and much of se Missouri. Temperatures should be a little cooler
north of the front, with highs Friday from 70 to 75.
&&
.AVIATION...
Issued at 1231 PM CDT Sat Apr 23 2016
The IFR ceilings at KPAH, KEVV and KOWB will dissipate by 19-21Z as
the low level moisture continues to steadily erode. Thereafter
mainly clear skies and light winds will prevail through the
reminder of the TAF periods as surface high pressure dominates.
Will include some limited fog tonight given very light to brief
calm winds and clear skies.
&&
.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
UPDATE...RLS
SHORT TERM...DRS
LONG TERM...MY
AVIATION...RS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1041 AM EDT SAT APR 23 2016
.UPDATE...
ISSUED AT 1041 AM EDT SAT APR 23 2016
THE UPPER LEVEL TROUGH AXIS CONTINUES TO SHIFT OFF TO THE
EAST...WITH HEIGHTS RECOVERING THE REST OF THE DAY. SPRINKLES/VERY
LIGHT RAIN SHOWERS HAVE EXITED OUR FAR SOUTHEAST...BUT CLOUDS
LOOK TO HANG TOUGH TODAY AND MODELS ARE A BIT OPTIMISTIC WITH THE
CLEARING COMPARED TO THE VISIBLE SATELLITE TRENDS. GIVEN THE LOW
LEVEL NORTH TO NORTHEAST FLOW AND MAINLY NEUTRAL ADVECTION AT 850
MB...HAVE ALLOWED THE CLOUDS TO HANG ON LONGER. CONSEQUENTLY...
TEMPERATURES ARE ALSO RUNNING A BIT COOLER...SO HAVE LOWERED THE
HIGHS SOMEWHAT...MAINLY LOW TO MID 60S FOR MOST EAST OF
I-75...WITH UPPER 60S TO AROUND 70 WEST OF I-75...WHERE CLEARING
WILL TAKE PLACE THE QUICKEST. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 736 AM EDT SAT APR 23 2016
RADAR CONTINUES TO SHOW LIGHT RETURNS ACROSS THE HIGHER TERRAIN
WHERE LOW LEVELS REMAIN SATURATED BENEATH A LOW STRATUS DECK. HAVE
THEREFORE INSERTED SPRINKLES THROUGH MID MORNING AS NOTHING MORE
THAN A TRACE OF PRECIPITATION SHOULD BE POSSIBLE. REDUCED
VISIBILITIES ALSO OCCURRING IN SPOTS...BUT BLANKET OF LOW CLOUDS
SHOULD NEGATE ANY THREAT FOR WIDESPREAD DENSE FOG.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 338 AM EDT SAT APR 23 2016
UPPER TROUGH CURRENTLY PUSHING EAST ACROSS WEST VIRGINIA WILL
BRING DEEP LAYER SUBSIDENCE TO EASTERN KENTUCKY...LEADING TO
GRADUALLY CLEARING SKIES LATER THIS MORNING. BEFORE THEN...A BATCH
OF LOW STRATUS WILL CONTINUE TO PROPAGATE SOUTH ACROSS THE OHIO
VALLEY AND INTO THE COMMONWEALTH AHEAD OF A SURFACE RIDGE BUILDING
ACROSS THE GREAT LAKES AS LOW LEVELS REMAIN RATHER MOIST. THIS
SHOULD KEEP FOG PATCHY IN NATURE AS RADIATIONAL COOLING WILL BE
IMPEDED BY THE INCOMING CLOUD DECK. HOWEVER...NOT EXPECTING ANY
ADDITIONAL RAINFALL WITH UPPER SUPPORT OFF TO THE EAST AND DRYING
MID-UPPER LEVELS.
WILL SEE ALL FOG MIX OUT BY MID-LATE MORNING AS DRIER AIR
CONTINUES TO BUILD TOWARD THE SURFACE. CLOUD COVER WILL ERODE WITH
SKIES CLEARING OUT BY LATER THIS AFTERNOON INTO TONIGHT. LIGHT
NORTHERLY WINDS WILL BRING SUBTLE COOL AIR ADVECTION AND ACT TO
HOLD HIGH TEMPERATURES THIS AFTERNOON IN THE MID 60S TO LOW 70S.
SURFACE HIGH PRESSURE MIGRATING ACROSS THE EASTERN GREAT LAKES
INTO THE APPALACHIANS WILL KEEP SKIES CLEAR TONIGHT AND WINDS
LIGHT. GIVEN RECENT PRECIPITATION FRIDAY...AT LEAST PATCHY VALLEY
FOG SHOULD BE A CERTAINTY AS AN APPRECIABLE RIDGE/VALLEY SPLIT
DEVELOPS. EXPECT A FEW OF THE MORE SHELTERED VALLEY LOCALES TO
DROP INTO THE UPPER 30S WITH MOST RIDGE LOCATIONS GENERALLY IN THE
LOW-MID 40S.
BUILDING HEIGHTS ALOFT AND VEERING SOUTHERLY WINDS WILL LEAD TO A
NOTICEABLE WARMUP FOR SUNDAY AS TEMPERATURES TOP OUT IN THE UPPER
70S TO LOWER 80S.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 338 AM EDT SAT APR 23 2016
OUR WEATHER SHOULD BE MORE ACTIVE NEXT WEEK AS SHORTWAVES EJECT
OUT OF A WESTERN CONUS THROUGH AND TRACK JUST TO OUR WEST INTO THE
UPPER MIDWEST AND GREAT LAKES REGION. AT THE SURFACE...A FRONTAL
BOUNDARY WILL DROP INTO THE REGION BY TUESDAY AND HANG AROUND
THROUGH MIDWEEK. A LOW PRESSURE SYSTEM WILL ALSO GET ORGANIZED
OVER THE PLAINS MIDWEEK. THIS SYSTEM WILL TRACK EASTWARD SENDING A
COLD FRONT TOWARD OUR REGION LATE IN THE WORK WEEK.
SENSIBLE WEATHER WILL FEATURE A NICE WARM MONDAY WITH PLENTY OF
SUNSHINE AND HIGHS IN THE LOW TO MID 80S. THE THREAT FOR SHOWERS
AND THUNDERSTORMS WILL THEN INCREASE FROM NORTH TO SOUTH LATE
MONDAY NIGHT INTO TUESDAY AS THE FRONT DROPS SOUTH INTO THE
REGION. JUST SCATTERED SHOWERS/STORMS ARE ANTICIPATED TUESDAY AND
WEDNESDAY AS THE FRONT IS NOT PARTICULARLY STRONG OR EQUIPPED WITH
MUCH MOISTURE. OUR BEST CHANCE FOR SHOWERS/STORMS APPEARS TO BE
WEDNESDAY NIGHT INTO THE DAY ON THURSDAY AS THE COLD FRONT ENTERS
THE SCENE FROM THE WEST. LESSER RAIN CHANCES ARE FORECAST FOR
FRIDAY...BUT CANNOT REMOVE THEM TOTALLY WITH THE FRONT AND
ACCOMPANYING LOW PRESSURE SYSTEM REMAINING NEARBY PER THE GFS AND
ECMWF.
DESPITE THE DAILY CHANCE OF RAIN TUESDAY THROUGH FRIDAY...A
WIDESPREAD SOAKING RAINFALL APPEARS UNLIKELY AT THIS TIME.
ALSO...DESPITE THE FRONTAL PASSAGE LATE IN THE WEEK...TEMPS WILL
REMAIN WELL ABOVE NORMAL...ONLY DROPPING FROM THE LOW TO MID 80S
TUESDAY THROUGH THURSDAY TO THE MID TO UPPER 70S ON FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 736 AM EDT SAT APR 23 2016
LOW STRATUS CONTINUES TO MAINTAIN GENERALLY MVFR CEILINGS...WITH
ISOLATED LIFR/IFR ALSO POSSIBLE FOR THE NEXT HOUR OR TWO AT
KJKL/KSJS/KSYM. WILL SEE ALL CEILINGS LIFT WITH VFR CONDITIONS
RETURNING BY LATE MORNING. CONTINUED INTRUSION OF DRIER
AIR...THANKS TO HIGH PRESSURE BUILDING IN...WILL CLEAR SKIES
THROUGH THE DAY. LIGHT NORTH WINDS WILL VEER EAST AND SOUTHEAST
THIS EVENING INTO TONIGHT. WILL HAVE TO MONITOR FOG/LOW CEILING
POTENTIAL TONIGHT INTO SUNDAY MORNING WITH CLEAR AND CALM
CONDITIONS IN PLACE...BUT WILL OPT TO KEEP MENTION SILENT FOR NOW
UNTIL SPATIAL/TIMING RESOLUTION BECOME BETTER REFINED.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...GUSEMAN
LONG TERM...ABE
AVIATION...GUSEMAN
Area Forecast Discussion
National Weather Service Paducah KY
939 AM CDT SAT APR 23 2016
.UPDATE...
Issued at 939 AM CDT Sat Apr 23 2016
Updated for Today due to clouds. Pesky thin layer of low clouds
will remain through much of the morning before mostly dissipating
by early afternoon. Have adjusted today`s max temps down a degree
or two in the central and eastern parts of the FA where cloud
cover is extensive this morning.
&&
.SHORT TERM...(Today through Monday night)
Issued at 304 AM CDT Sat Apr 23 2016
The main issue early this morning is surface high pressure surging
southwest into the region. It is keeping the northeast winds
stirred up and ushering in a solid layer of IFR level clouds that
guidance does not have a good handle on. The clouds now cover much
of the Evansville Tri State, and should continue to push
southward, per the RAP low-level RH forecast, toward the Lakes and
Pennyrile. Figure that the low clouds will dissipate quickly this
morning by 15Z.
The clouds will have more of an impact on aviation concerns, and
the AVIATION of this discussion has been updated as well.
Temperatures may be held up just a bit under the cloud cover
through daybreak, but not much, and they may hold down highs a
degree or two in the east. With plenty of sunshine expected this
afternoon and dry air in place over the region, this forecast still
leaned toward the warmer side of the guidance envelope for highs.
Surface high pressure will continue to dominate the region tonight,
so clear skies and light winds will allow for good radiational
cooling. Definitely went at or below coolest guidance for tonight`s
lows in most locations. The surface high will push east of the
area on Sunday, allowing south winds to return across the region.
With high pressure aloft resulting in mostly sunny skies, went at
or above the warmest guidance. Most of the area should be in the
lower 80s.
South winds will stay up in the 5 to 10 mph range Sunday night, so
it should be a milder night. Skies will still be no worse than
partly cloudy, so will not go much above guidance. Lows should be
around 60.
As our next potential storm system settles over the Four Corners
region Monday, the flow aloft over our region will become nearly
zonal. A surface cold front will become strung out nearly west to
east well to our north. This should keep us high and dry Monday
and most likely Monday night, too. Will have the slightest of PoPs
for SHRA/TSRA in the Perryville, Pinckneyville, and Mt Vernon
areas on Monday and along the I-64 corridor Monday night, but this
is mainly just to provide a buffer with our surrounding forecast
areas.
The 00Z models do not indicate much increase in clouds Monday, so
temperatures should soar into the 80-85F range, which is well above
guidance. Lows Monday night will continue to trend milder. With a
bit more wind expected, and increasing clouds overnight, lows will
be in the 60-65F range.
.LONG TERM...(Tuesday through Friday)
Issued at 304 AM CDT Sat Apr 23 2016
The upper-level split flow pattern will consist of an active
southern stream across the United States, and a more diffuse polar
jet across northern Canada. A series of shortwaves will eject
northeast out of the Desert Southwest to the central Plains, then
finally into the Great Lakes before weakening. There are still
significant model differences concerning the timing of these
shortwaves and their associated frontal systems. Overall, the
pattern looks rather warm and wet given the storm track to our
north.
As far as the daily specifics, the models are in good agreement for
Tuesday. A narrow 500 mb ridge will pass over the Mississippi Valley
ahead of the first shortwave, which will be emerging into the
southern high Plains. Beneath the ridge aloft, the models continue
to sag a weak frontal boundary south to Interstate 64 by late in the
day Tuesday. The air mass is forecast to be warm and unstable south
of the front, moreso than with other fronts this spring. Therefore,
chance pops will be kept in the forecast despite weak forcing aloft.
The weak frontal boundary should continue south into the Lower Ohio
Valley Tuesday night. Beyond that, the models really start to
diverge on the timing of subsequent frontal passages. The front may
move south of our area before returning north as a warm front during
the middle of the week. A weakening surface low will then move east
across the Midwest Wednesday night and Thursday. A cold front
trailing southwest from the low will move across our region, but
timing differences are quite large. The faster 00z ecmwf is
consistent with the previous NWS forecast and the 12z Fri ecmwf
ensemble mean. However, the slower 00z gfs has support from the
00z gefs. In a nutshell, pops will be in the high chance to likely
category Wed and Wednesday night. Compared with previous systems
this spring, there will be plenty of moisture and instability for
convection. Wind profiles will be moderately strong. A few intense
storms are possible.
Late in the week, another weak shortwave ridge will traverse the
Mississippi and Ohio Valleys between systems. The weak cold front
will be suppressed south of our region. It now appears Friday will
be dry in many areas, but a slight chance pop will be retained
closer to the frontal boundary in the Tennessee border counties
and much of se Missouri. Temperatures should be a little cooler
north of the front, with highs Friday from 70 to 75.
&&
.AVIATION...
Issued at 639 AM CDT Sat Apr 23 2016
The IFR/LIFR ceilings reached all of the TAF sites except KCGI,
but MVFR visibilities were impacting the entire area. The low
clouds and fog should dissipate fairly quickly now that the sun is
up. It may take most of the morning for KOWB and KEVV to burn off.
Otherwise, the only potential concern to aviation is a possible
recurrence of fog or low cloud development late tonight. The
surface high is expected to shift eastward a bit, which will
hopefully keep any such development east of the TAF sites.
&&
.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
UPDATE...RS
SHORT TERM...DRS
LONG TERM...MY
AVIATION...DRS
AREA FORECAST DISCUSSION
NWS JACKSON KY
736 AM EDT SAT APR 23 2016
.UPDATE...
ISSUED AT 736 AM EDT SAT APR 23 2016
RADAR CONTINUES TO SHOW LIGHT RETURNS ACROSS THE HIGHER TERRAIN
WHERE LOW LEVELS REMAIN SATURATED BENEATH A LOW STRATUS DECK. HAVE
THEREFORE INSERTED SPRINKLES THROUGH MID MORNING AS NOTHING MORE
THAN A TRACE OF PRECIPITATION SHOULD BE POSSIBLE. REDUCED
VISIBILITIES ALSO OCCURRING IN SPOTS...BUT BLANKET OF LOW CLOUDS
SHOULD NEGATE ANY THREAT FOR WIDESPREAD DENSE FOG.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 338 AM EDT SAT APR 23 2016
UPPER TROUGH CURRENTLY PUSHING EAST ACROSS WEST VIRGINIA WILL
BRING DEEP LAYER SUBSIDENCE TO EASTERN KENTUCKY...LEADING TO
GRADUALLY CLEARING SKIES LATER THIS MORNING. BEFORE THEN...A BATCH
OF LOW STRATUS WILL CONTINUE TO PROPAGATE SOUTH ACROSS THE OHIO
VALLEY AND INTO THE COMMONWEALTH AHEAD OF A SURFACE RIDGE BUILDING
ACROSS THE GREAT LAKES AS LOW LEVELS REMAIN RATHER MOIST. THIS
SHOULD KEEP FOG PATCHY IN NATURE AS RADIATIONAL COOLING WILL BE
IMPEDED BY THE INCOMING CLOUD DECK. HOWEVER...NOT EXPECTING ANY
ADDITIONAL RAINFALL WITH UPPER SUPPORT OFF TO THE EAST AND DRYING
MID-UPPER LEVELS.
WILL SEE ALL FOG MIX OUT BY MID-LATE MORNING AS DRIER AIR
CONTINUES TO BUILD TOWARD THE SURFACE. CLOUD COVER WILL ERODE WITH
SKIES CLEARING OUT BY LATER THIS AFTERNOON INTO TONIGHT. LIGHT
NORTHERLY WINDS WILL BRING SUBTLE COOL AIR ADVECTION AND ACT TO
HOLD HIGH TEMPERATURES THIS AFTERNOON IN THE MID 60S TO LOW 70S.
SURFACE HIGH PRESSURE MIGRATING ACROSS THE EASTERN GREAT LAKES
INTO THE APPALACHIANS WILL KEEP SKIES CLEAR TONIGHT AND WINDS
LIGHT. GIVEN RECENT PRECIPITATION FRIDAY...AT LEAST PATCHY VALLEY
FOG SHOULD BE A CERTAINTY AS AN APPRECIABLE RIDGE/VALLEY SPLIT
DEVELOPS. EXPECT A FEW OF THE MORE SHELTERED VALLEY LOCALES TO
DROP INTO THE UPPER 30S WITH MOST RIDGE LOCATIONS GENERALLY IN THE
LOW-MID 40S.
BUILDING HEIGHTS ALOFT AND VEERING SOUTHERLY WINDS WILL LEAD TO A
NOTICEABLE WARMUP FOR SUNDAY AS TEMPERATURES TOP OUT IN THE UPPER
70S TO LOWER 80S.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 338 AM EDT SAT APR 23 2016
OUR WEATHER SHOULD BE MORE ACTIVE NEXT WEEK AS SHORTWAVES EJECT
OUT OF A WESTERN CONUS THROUGH AND TRACK JUST TO OUR WEST INTO THE
UPPER MIDWEST AND GREAT LAKES REGION. AT THE SURFACE...A FRONTAL
BOUNDARY WILL DROP INTO THE REGION BY TUESDAY AND HANG AROUND
THROUGH MIDWEEK. A LOW PRESSURE SYSTEM WILL ALSO GET ORGANIZED
OVER THE PLAINS MIDWEEK. THIS SYSTEM WILL TRACK EASTWARD SENDING A
COLD FRONT TOWARD OUR REGION LATE IN THE WORK WEEK.
SENSIBLE WEATHER WILL FEATURE A NICE WARM MONDAY WITH PLENTY OF
SUNSHINE AND HIGHS IN THE LOW TO MID 80S. THE THREAT FOR SHOWERS
AND THUNDERSTORMS WILL THEN INCREASE FROM NORTH TO SOUTH LATE
MONDAY NIGHT INTO TUESDAY AS THE FRONT DROPS SOUTH INTO THE
REGION. JUST SCATTERED SHOWERS/STORMS ARE ANTICIPATED TUESDAY AND
WEDNESDAY AS THE FRONT IS NOT PARTICULARLY STRONG OR EQUIPPED WITH
MUCH MOISTURE. OUR BEST CHANCE FOR SHOWERS/STORMS APPEARS TO BE
WEDNESDAY NIGHT INTO THE DAY ON THURSDAY AS THE COLD FRONT ENTERS
THE SCENE FROM THE WEST. LESSER RAIN CHANCES ARE FORECAST FOR
FRIDAY...BUT CANNOT REMOVE THEM TOTALLY WITH THE FRONT AND
ACCOMPANYING LOW PRESSURE SYSTEM REMAINING NEARBY PER THE GFS AND
ECMWF.
DESPITE THE DAILY CHANCE OF RAIN TUESDAY THROUGH FRIDAY...A
WIDESPREAD SOAKING RAINFALL APPEARS UNLIKELY AT THIS TIME.
ALSO...DESPITE THE FRONTAL PASSAGE LATE IN THE WEEK...TEMPS WILL
REMAIN WELL ABOVE NORMAL...ONLY DROPPING FROM THE LOW TO MID 80S
TUESDAY THROUGH THURSDAY TO THE MID TO UPPER 70S ON FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 736 AM EDT SAT APR 23 2016
LOW STRATUS CONTINUES TO MAINTAIN GENERALLY MVFR CEILINGS...WITH
ISOLATED LIFR/IFR ALSO POSSIBLE FOR THE NEXT HOUR OR TWO AT
KJKL/KSJS/KSYM. WILL SEE ALL CEILINGS LIFT WITH VFR CONDITIONS
RETURNING BY LATE MORNING. CONTINUED INTRUSION OF DRIER
AIR...THANKS TO HIGH PRESSURE BUILDING IN...WILL CLEAR SKIES
THROUGH THE DAY. LIGHT NORTH WINDS WILL VEER EAST AND SOUTHEAST
THIS EVENING INTO TONIGHT. WILL HAVE TO MONITOR FOG/LOW CEILING
POTENTIAL TONIGHT INTO SUNDAY MORNING WITH CLEAR AND CALM
CONDITIONS IN PLACE...BUT WILL OPT TO KEEP MENTION SILENT FOR NOW
UNTIL SPATIAL/TIMING RESOLUTION BECOME BETTER REFINED.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GUSEMAN
SHORT TERM...GUSEMAN
LONG TERM...ABE
AVIATION...GUSEMAN
Area Forecast Discussion
National Weather Service Louisville KY
651 AM EDT SAT APR 23 2016
...Updated Aviation Discussion...
.SHORT TERM (Now through Sunday)...
Issued 240 AM EDT Sat Apr 23 2016
...A pleasant weekend in store...
The synoptic pattern early this morning features a weak trough
across the eastern CONUS, with another more substantial trough
building into the western CONUS. Ridging in between these two
features will build into the Ohio Valley through the period,
bringing a very pleasant weekend to the region.
Low clouds continue to stream in from the north early this morning.
The latest HRRR has a pretty good handle on these clouds, thus have
leaned toward its solution for today. These clouds should mix out
pretty quickly by mid to late morning, making way for quite a bit of
sunshine this afternoon. The clouds may slow our temperatures rise
a bit this morning, but think the solar insolation this afternoon
should be enough to get temperatures into the upper 60s and lower
70s.
Surface ridging will slide east of the region tonight into Sunday.
Southerly flow will commence on the backside of this high, which
will allow temperatures to warm up for Sunday. Will go above the
general guidance consensus, which places highs in the lower 80s
under mostly sunny skies.
.LONG TERM (Sunday night through Friday)...
Issued at 310 AM EDT Sat Apr 23 2016
...A more active convective weather pattern at times next week...
The synoptic pattern at the start of the long term period will
feature zonal to WSW flow over the Ohio Valley due to an upstream
western CONUS trough. This regime will allow for a couple of
disturbances to eject out of the trough which will make for a more
active weather pattern beginning around Monday night/Tuesday of next
week.
While confidence in the overall pattern is high, confidence in
timing of each feature ejecting out of the western trough is rather
low. As a result, have gone with more of an ensemble approach to
the forecast and stuck with a general model/ensemble blend.
A warm front will sharpen well to the north of the region on Monday.
As a result, any precipitation will remain out of the Ohio Valley
which will allow us to warm rather nicely during the afternoon hours
as we will sit on the warm side of the boundary. Have upper highs
well into the 80s on Monday afternoon, with some upper 80s readings
not out of the question in the typically warmer locations.
The first PV anomaly will slide southeast along the front Monday
night into Tuesday. This will help push the front into the Ohio
River Valley, sparking showers and thunderstorms as it drives
southeast. The kinematics with this system are not impressive, with
deep layer shear only around 20-30 knots, so do not see an organized
severe threat with this activity on Tuesday (maybe just a few strong
storms depending on how well we destabilize).
The western trough will begin to eject into the Central Plains late
Tuesday into Wednesday, which will push the cold front back to the
north as a warm front. A few thunderstorms will be possible
Wednesday along/south of the boundary lifting north, but it appears
the better chance of thunderstorms will come mainly Wednesday night
as the main forcing for ascent pushes through the Ohio Valley. Wind
fields are more impressive with this system, but timing as it stands
now is not very favorable. However, we will continue to monitor
this system closely as substantial differences remain in the
deterministic/ensemble guidance suite.
The GFS is much slower, keeping storm chances going through
Thursday, with the ECMWF showing a much drier solution. Will split
the difference and continue with chance pops Thursday, but go mainly
dry for Friday as the guidance consensus is to finally push the cold
front to the south of the region.
Temperatures through the period will be very dependent on the timing
of precipitation, but highs generally in the 80s with lows in the
upper 50s/60s is likely through much of next week, until the
slightly cooler air arrives Friday.
&&
.AVIATION (12Z TAF Update)...
Updated at 650 AM EDT Sat Apr 23 2016
Batch of low level clouds will continue to drop southward through KY
this morning. Ceilings are expected to run around 1-1.5Kft AGL this
morning with a light northerly wind. Some light fog will also be
possible for a time this morning. Overall visibilities should run
in the MVFR range with 4-5SM expected. The low cloud deck is
forecast to mixout around 23/14-16Z with VFR conditions expected at
all the terminals after 23/17Z. VFR conditions are expected this
afternoon and tonight with just a light northeasterly breeze.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Short Term........KJD
Long Term.........KJD
Aviation..........MJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
338 AM EDT SAT APR 23 2016
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 338 AM EDT SAT APR 23 2016
UPPER TROUGH CURRENTLY PUSHING EAST ACROSS WEST VIRGINIA WILL
BRING DEEP LAYER SUBSIDENCE TO EASTERN KENTUCKY...LEADING TO
GRADUALLY CLEARING SKIES LATER THIS MORNING. BEFORE THEN...A BATCH
OF LOW STRATUS WILL CONTINUE TO PROPAGATE SOUTH ACROSS THE OHIO
VALLEY AND INTO THE COMMONWEALTH AHEAD OF A SURFACE RIDGE BUILDING
ACROSS THE GREAT LAKES AS LOW LEVELS REMAIN RATHER MOIST. THIS
SHOULD KEEP FOG PATCHY IN NATURE AS RADIATIONAL COOLING WILL BE
IMPEDED BY THE INCOMING CLOUD DECK. HOWEVER...NOT EXPECTING ANY
ADDITIONAL RAINFALL WITH UPPER SUPPORT OFF TO THE EAST AND DRYING
MID-UPPER LEVELS.
WILL SEE ALL FOG MIX OUT BY MID-LATE MORNING AS DRIER AIR
CONTINUES TO BUILD TOWARD THE SURFACE. CLOUD COVER WILL ERODE WITH
SKIES CLEARING OUT BY LATER THIS AFTERNOON INTO TONIGHT. LIGHT
NORTHERLY WINDS WILL BRING SUBTLE COOL AIR ADVECTION AND ACT TO
HOLD HIGH TEMPERATURES THIS AFTERNOON IN THE MID 60S TO LOW 70S.
SURFACE HIGH PRESSURE MIGRATING ACROSS THE EASTERN GREAT LAKES
INTO THE APPALACHIANS WILL KEEP SKIES CLEAR TONIGHT AND WINDS
LIGHT. GIVEN RECENT PRECIPITATION FRIDAY...AT LEAST PATCHY VALLEY
FOG SHOULD BE A CERTAINTY AS AN APPRECIABLE RIDGE/VALLEY SPLIT
DEVELOPS. EXPECT A FEW OF THE MORE SHELTERED VALLEY LOCALES TO
DROP INTO THE UPPER 30S WITH MOST RIDGE LOCATIONS GENERALLY IN THE
LOW-MID 40S.
BUILDING HEIGHTS ALOFT AND VEERING SOUTHERLY WINDS WILL LEAD TO A
NOTICEABLE WARMUP FOR SUNDAY AS TEMPERATURES TOP OUT IN THE UPPER
70S TO LOWER 80S.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 338 AM EDT SAT APR 23 2016
OUR WEATHER SHOULD BE MORE ACTIVE NEXT WEEK AS SHORTWAVES EJECT
OUT OF A WESTERN CONUS THROUGH AND TRACK JUST TO OUR WEST INTO THE
UPPER MIDWEST AND GREAT LAKES REGION. AT THE SURFACE...A FRONTAL
BOUNDARY WILL DROP INTO THE REGION BY TUESDAY AND HANG AROUND
THROUGH MIDWEEK. A LOW PRESSURE SYSTEM WILL ALSO GET ORGANIZED
OVER THE PLAINS MIDWEEK. THIS SYSTEM WILL TRACK EASTWARD SENDING A
COLD FRONT TOWARD OUR REGION LATE IN THE WORK WEEK.
SENSIBLE WEATHER WILL FEATURE A NICE WARM MONDAY WITH PLENTY OF
SUNSHINE AND HIGHS IN THE LOW TO MID 80S. THE THREAT FOR SHOWERS
AND THUNDERSTORMS WILL THEN INCREASE FROM NORTH TO SOUTH LATE
MONDAY NIGHT INTO TUESDAY AS THE FRONT DROPS SOUTH INTO THE
REGION. JUST SCATTERED SHOWERS/STORMS ARE ANTICIPATED TUESDAY AND
WEDNESDAY AS THE FRONT IS NOT PARTICULARLY STRONG OR EQUIPPED WITH
MUCH MOISTURE. OUR BEST CHANCE FOR SHOWERS/STORMS APPEARS TO BE
WEDNESDAY NIGHT INTO THE DAY ON THURSDAY AS THE COLD FRONT ENTERS
THE SCENE FROM THE WEST. LESSER RAIN CHANCES ARE FORECAST FOR
FRIDAY...BUT CANNOT REMOVE THEM TOTALLY WITH THE FRONT AND
ACCOMPANYING LOW PRESSURE SYSTEM REMAINING NEARBY PER THE GFS AND
ECMWF.
DESPITE THE DAILY CHANCE OF RAIN TUESDAY THROUGH FRIDAY...A
WIDESPREAD SOAKING RAINFALL APPEARS UNLIKELY AT THIS TIME.
ALSO...DESPITE THE FRONTAL PASSAGE LATE IN THE WEEK...TEMPS WILL
REMAIN WELL ABOVE NORMAL...ONLY DROPPING FROM THE LOW TO MID 80S
TUESDAY THROUGH THURSDAY TO THE MID TO UPPER 70S ON FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 150 AM EDT SAT APR 23 2016
MAIN ISSUE THIS CYCLE WILL BE LOW STRATUS APPROACHING FROM THE
OHIO VALLEY. HAVE SEEN SEVERAL BREAKS IN THIS...SUGGESTING NOT
EVERYONE WILL SEE PERSISTENT LOWERING CEILINGS. MVFR CEILINGS LOOK
LIKE A DECENT BET FOR ALL SITES AT SOME POINT. FOG AND REDUCED
VISIBILITIES MAY BECOME AN ISSUE IN LIEU OF LOWERING CEILINGS
LATER TONIGHT AND SATURDAY MORNING. LIGHT NORTHWEST WINDS WILL
CONTINUE THROUGH THE PERIOD AS CLOUD COVER SLOWLY DECREASES
THROUGH THE DAY SATURDAY AS HIGH PRESSURE SETTLES INTO EASTERN
KENTUCKY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GUSEMAN
LONG TERM...ABE
AVIATION...GUSEMAN
Area Forecast Discussion
National Weather Service Louisville KY
312 AM EDT SAT APR 23 2016
.SHORT TERM (Now through Sunday)...
Issued 240 AM EDT Sat Apr 23 2016
...A pleasant weekend in store...
The synoptic pattern early this morning features a weak trough
across the eastern CONUS, with another more substantial trough
building into the western CONUS. Ridging in between these two
features will build into the Ohio Valley through the period,
bringing a very pleasant weekend to the region.
Low clouds continue to stream in from the north early this morning.
The latest HRRR has a pretty good handle on these clouds, thus have
leaned toward its solution for today. These clouds should mix out
pretty quickly by mid to late morning, making way for quite a bit of
sunshine this afternoon. The clouds may slow our temperatures rise
a bit this morning, but think the solar insolation this afternoon
should be enough to get temperatures into the upper 60s and lower
70s.
Surface ridging will slide east of the region tonight into Sunday.
Southerly flow will commence on the backside of this high, which
will allow temperatures to warm up for Sunday. Will go above the
general guidance consensus, which places highs in the lower 80s
under mostly sunny skies.
.LONG TERM (Sunday night through Friday)...
Issued at 310 AM EDT Sat Apr 23 2016
...A more active convective weather pattern at times next week...
The synoptic pattern at the start of the long term period will
feature zonal to WSW flow over the Ohio Valley due to an upstream
western CONUS trough. This regime will allow for a couple of
disturbances to eject out of the trough which will make for a more
active weather pattern beginning around Monday night/Tuesday of next
week.
While confidence in the overall pattern is high, confidence in
timing of each feature ejecting out of the western trough is rather
low. As a result, have gone with more of an ensemble approach to
the forecast and stuck with a general model/ensemble blend.
A warm front will sharpen well to the north of the region on Monday.
As a result, any precipitation will remain out of the Ohio Valley
which will allow us to warm rather nicely during the afternoon hours
as we will sit on the warm side of the boundary. Have upper highs
well into the 80s on Monday afternoon, with some upper 80s readings
not out of the question in the typically warmer locations.
The first PV anomaly will slide southeast along the front Monday
night into Tuesday. This will help push the front into the Ohio
River Valley, sparking showers and thunderstorms as it drives
southeast. The kinematics with this system are not impressive, with
deep layer shear only around 20-30 knots, so do not see an organized
severe threat with this activity on Tuesday (maybe just a few strong
storms depending on how well we destabilize).
The western trough will begin to eject into the Central Plains late
Tuesday into Wednesday, which will push the cold front back to the
north as a warm front. A few thunderstorms will be possible
Wednesday along/south of the boundary lifting north, but it appears
the better chance of thunderstorms will come mainly Wednesday night
as the main forcing for ascent pushes through the Ohio Valley. Wind
fields are more impressive with this system, but timing as it stands
now is not very favorable. However, we will continue to monitor
this system closely as substantial differences remain in the
deterministic/ensemble guidance suite.
The GFS is much slower, keeping storm chances going through
Thursday, with the ECMWF showing a much drier solution. Will split
the difference and continue with chance pops Thursday, but go mainly
dry for Friday as the guidance consensus is to finally push the cold
front to the south of the region.
Temperatures through the period will be very dependent on the timing
of precipitation, but highs generally in the 80s with lows in the
upper 50s/60s is likely through much of next week, until the
slightly cooler air arrives Friday.
&&
.AVIATION (06Z TAF Update)...
Updated at 1255 AM EDT Sat Apr 23 2016
Overnight concern remains on low clouds currently dropping southward
through central Indiana this morning. Last few runs of the HRRR and
HRRRX suggest that this trend will continue and the low cloudiness
would expand across KY overnight. Given current trends, it appears
that may be a little overdone. However, it does look like some low
clouds will likely affect KSDF between roughly 23/08 through about
23/14Z. Some MVFR cloudiness may affect KLEX between 23/08-14Z as
well. Further south at KBWG, surface patchy fog may be more of an
issue than the low cloudiness. Surface winds overnight will remain
out of the north and light. A return to VFR conditions is expected
Saturday morning with the terminals seeing mostly clear skies after
23/15Z.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Short Term........KJD
Long Term.........KJD
Aviation..........MJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
150 AM EDT SAT APR 23 2016
.UPDATE...
ISSUED AT 150 AM EDT SAT APR 23 2016
LOW STRATUS CONTINUES TO TRACK SOUTH ACROSS THE OHIO VALLEY TOWARD
THE COMMONWEALTH. SEVERAL BREAKS CAN BE SEEN IN SATELLITE
IMAGERY...SUGGESTING A NON-UNIFORM PATTERN TO THE CLOUD COVER. IF
SKIES CAN REMAIN MOSTLY CLEAR FOR A MAJORITY OF TONIGHT/EARLY
SATURDAY...MAY SEE AN UPTICK IN FOG THICKNESS AND COVERAGE AND
NEED TO BEEF UP WORDING IN THE FORECAST. FOR NOW...PATCHY FOG
REMAINS IN PLAY PENDING EVOLUTION OF INCOMING STRATUS.
UPDATE ISSUED AT 1036 PM EDT FRI APR 22 2016
CURRENT CONDITIONS ACROSS EASTERN KENTUCKY POSE AN INTERESTING
FORECAST PROBLEM FOR TONIGHT. UPDATED THE FORECAST TO REMOVE POPS
FOR THE NIGHT AS ALL THIS ACTIVITY HAS EXITED AND WHILE SOME
UPPER LEVEL SUPPORT IS STILL PASSING THROUGH TO THE NORTH...NO
PRECIP IS EXPECTED TONIGHT. THE SECOND ISSUE IS CONCERNING THE LOW
LEVEL CLOUD COVER TO THE NORTHWEST. AT THE CURRENT TIME...THIS IS
SLOW TO MOVE INTO EASTERN KENTUCKY. THE CONCERN IS THAT IF THERE
ARE MORE BREAKS IN THE CLOUD COVER TONIGHT WITH THE RAINFALL FROM
EARLIER TODAY...THE FOG WILL BECOME MORE EXTENSIVE AND EVEN DENSE
IN SOME AREAS. FOR NOW HAVE ADDED PATCHY FOG TO THE ZFP BUT THIS
MAY NEED TO BE REEVALUATED IF THE CLOUD COVER DOES NOT SET UP
TONIGHT. A NEW ZFP HAS BEEN SENT AND THE HWO WAS UPDATED TO REMOVE
THUNDER.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 340 PM EDT FRI APR 22 2016
LATEST RADAR IMAGERY SHOWS THREE SEPARATE LINES/AREAS OF
SHOWERS/THUNDERSTORMS...THE FIRST OF WHICH IS CURRENTLY MOVING
THROUGH EASTERN KENTUCKY AND HAS PRODUCED PEA AND NICKEL SIZE
HAIL. THE SECOND LINE IS DEVELOPING ALONG THE WESTERN BORDER OF
THE FORECAST AREA AND IS ASSOCIATED WITH THE COLD FRONT.
FINALLY...THE THIRD AREA OF SHOWERS/STORMS IS ASSOCIATED WITH THE
UPPER LEVEL LOW AND IS LOCATED OVER NORTH CENTRAL KY/SOUTHWEST OH
ATTM. THESE THREE ROUNDS OF RAIN/THUNDERSTORMS WILL CONTINUE TO
MOVE THROUGH THE AREA THIS EVENING AND INTO THE OVERNIGHT HOURS
BUT THE STRENGTH OF THE STORMS SHOULD WANE A BIT AFTER SUNSET.
THROUGH THIS EVENING...HOWEVER...SMALL HAIL AND GUSTY WINDS WILL
BE POSSIBLE WITH ANY STRONG STORM.
RAIN SHOULD EXIT TO OUR EAST BY 06Z AS THE UPPER LEVEL LOW SHIFTS
INTO WEST VIRGINIA. RIDGING WILL BUILD INTO THE REGION THROUGHOUT
THE DAY ON SATURDAY...HELPING TO CLEAR OUT THE CLOUDS AND BRING A
RETURN OF SUNSHINE FOR MOST OF THE WEEKEND.
TEMPERATURES THROUGH THE SHORT TERM WILL REMAIN NEAR NORMAL WITH
LOWS BOTH NIGHTS IN THE UPPER 40S/LOW 50S AND AFTERNOON HIGHS NEAR
THE 70 DEGREE MARK.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 340 PM EDT FRI APR 22 2016
DRY WARM WEATHER WILL PREVAIL FOR THE LATTER PART OF THE WEEKEND AND
INTO EARLY NEXT WEEK AS HIGH PRESSURE DRIFTS EAST ACROSS THE GREAT
LAKES AND OH VALLEY. NEXT WEEK WILL FEATURE A LARGE UPPER LEVEL LOW
MOVING FROM THE SOUTHWEST UNITED STATES TOWARDS THE GREAT LAKES FROM
TUESDAY INTO THURSDAY. AT THE SURFACE A FRONTAL BOUNDARY WILL DRIFT
SOUTH INTO THE OH AND TN VALLEYS AND REMAIN IN THE VICINITY OF KY.
THIS WILL RESULT IN SHOWER AND THUNDERSTORM CHANCES FROM THE TUESDAY
THROUGH THE REMAINDER OF THE WEEK. THE BEST DYNAMICS WILL REMAIN
WELL TO OUR WEST NEXT WEEK...WITH THE CHANCES FOR STRONGER STORMS
BEING OVER THE PLAINS INTO THE MS VALLEY. TEMPERATURES WILL CONTINUE
TO RUN ABOVE NORMAL NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 150 AM EDT SAT APR 23 2016
MAIN ISSUE THIS CYCLE WILL BE LOW STRATUS APPROACHING FROM THE
OHIO VALLEY. HAVE SEEN SEVERAL BREAKS IN THIS...SUGGESTING NOT
EVERYONE WILL SEE PERSISTENT LOWERING CEILINGS. MVFR CEILINGS LOOK
LIKE A DECENT BET FOR ALL SITES AT SOME POINT. FOG AND REDUCED
VISIBILITIES MAY BECOME AN ISSUE IN LIEU OF LOWERING CEILINGS
LATER TONIGHT AND SATURDAY MORNING. LIGHT NORTHWEST WINDS WILL
CONTINUE THROUGH THE PERIOD AS CLOUD COVER SLOWLY DECREASES
THROUGH THE DAY SATURDAY AS HIGH PRESSURE SETTLES INTO EASTERN
KENTUCKY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GUSEMAN
SHORT TERM...JVM
LONG TERM...SBH
AVIATION...GUSEMAN
Area Forecast Discussion
National Weather Service Louisville KY
1255 AM EDT SAT APR 23 2016
...Updated Aviation Discussion...
.SHORT TERM (Now through Sunday)...
Issued 300 PM EDT Fri Apr 22 2016
...Scattered showers til early evening then a nice weather weekend...
As expected, scattered to numerous showers and thunderstorms have
developed immediately south and east of the mid-level trough, with
greatest precip coverage over our northern and eastern counties. In
these areas, marginal instability (surface-based lifted indices -2
to -3 and CAPE 500-1000 J/kg) is supporting the convective elements.
The strongest cores will be capable of pea size hail (we received
one such report so far), brief heavy rain, and several lightning
strikes. By early evening as daytime heating wanes, showers will
weaken and eventually dissipate. Thereafter, model cross-sections
suggest that some low clouds may persistent or develop later tonight
in areas, with some light fog possible in some locations.
For Saturday and Sunday, a ridge of high pressure at the surface
will cross the Ohio Valley with plenty of sunshine. There could be a
few flat afternoon cumulus clouds Saturday and some high cirrus
Sunday, but that`s about it. Nights will be cool in the upper 40s
and lower 50s Saturday morning, and mid 40s to about 50 Sunday
morning. Highs Saturday afternoon will be in the upper 60s in east-
central KY to lower 70s elsewhere. Warmer Sunday with highs in the
upper 70s and lower 80s. Winds Saturday will be northeast 5-10 mph
and south 5-10 mph on Sunday.
.LONG TERM (Sunday night through Friday)...
Issued at 315 PM EDT Fri Apr 22 2016
...A more active convective weather pattern at times next week...
Pattern in the extended will feature a mean trough in the western
U.S. and a mix of more zonal flow or flat ridging over the Ohio
Valley. At least two strong systems are progged by all models to
eject out of the western trough next week through next weekend, with
severe weather at times over the southern-central Plains into the
mid MS Valley, and possibly into the Ohio Valley.
Monday-Tuesday...
On Monday, a shortwave will move across the northern Plains then
across the Great Lakes. This will drive a cold front southeastward
across the Ohio Valley late Monday and Tuesday. The air mass south
of the front will be warm (generally lower-mid 80s) and become more
unstable. Scattered thunderstorms could develop late Monday night
over southern IN closer to the front, and areawide on Tuesday along
and south of the boundary. Models differ on frontal location with
GFS a little farther south than ECMWF. Either way, the boundary will
become stationary over/near the area. Organized severe storms are
not expected but a few strong storms are certainly possible Tuesday
afternoon. Models suggest that scattered showers and storms could
occur or move in from the west Tuesday night as well(especially the
GEM model).
Wednesday-Wednesday night...
As a strong storm system ejects out of the southwestern U.S. and
across the Plains states Tuesday, thunderstorms could push into or
through the mid MS Valley by Wednesday morning. Much uncertainty
exists with how potential severe weather well to our south and west
Tuesday afternoon and night will evolve and affect our area
Wednesday and Wednesday night, as well as the interaction with the
frontal zone in our vicinity. It is possible that some remnant
storms could affect our area first half of Wednesday. However, late
Wednesday and/or Wednesday night looks potentially interesting as a
moderately unstable air mass develops (assuming enough diurnal
isolation) and as the exit region of a mid/upper level jet streak
approaches the Ohio Valley. This could potentially result in
cellular and/or linear convection during this time, with a few
severe storms possible. Our forecast will carry higher probabilities
of precip during this time period.
Thursday-Friday...
Depending on how the Wednesday system evolves, associated
convection could linger or redevelop along a trailing cold front
Thursday afternoon, but be more scattered in nature. Then drier air
should return by Friday as the system moves through. Highs Friday
should be cooler in the post-frontal air mass than on Thursday.
Next Saturday-Sunday...
Although this is past the current forecast period, another strong
system could eject out of the southwestern U.S. and across the
Plains. This could bring another round of convection to the Ohio
Valley sometime next weekend.
&&
.AVIATION (06Z TAF Update)...
Updated at 1255 AM EDT Sat Apr 23 2016
Overnight concern remains on low clouds currently dropping southward
through central Indiana this morning. Last few runs of the HRRR and
HRRRX suggest that this trend will continue and the low cloudiness
would expand across KY overnight. Given current trends, it appears
that may be a little overdone. However, it does look like some low
clouds will likely affect KSDF between roughly 23/08 through about
23/14Z. Some MVFR cloudiness may affect KLEX between 23/08-14Z as
well. Further south at KBWG, surface patchy fog may be more of an
issue than the low cloudiness. Surface winds overnight will remain
out of the north and light. A return to VFR conditions is expected
Saturday morning with the terminals seeing mostly clear skies after
23/15Z.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Short Term........TWF
Long Term.........TWF
Aviation..........MJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
715 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 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 715 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/LIFR CATEGORY AT KIWD/KCMX/KSAW.
&&
.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...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
512 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 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 139 PM EDT SAT APR 23 2016
VFR CONDITIONS WILL LIKELY HOLD ON THRU THE EVENING AT
KIWD/KCMX/KSAW UNDER ONLY BKN-OVC MID LEVEL CLOUDS. LIGHT RAIN WILL
ARRIVE TONIGHT AND CONTINUE THRU SUN. CIGS WILL BEGIN TO STEADILY
LOWER OVERNIGHT AS STEADIER RAIN ARRIVES...REACHING IFR AT ALL
TERMINALS AROUND 12Z. CONDITIONS MAY CONTINUE TO DETERIORATE FURTHER
TO LIFR DURING THE MORNING HRS...PARTICULARLY AT KCMX/KSAW UNDER
UPSLOPE WINDS. VIS SHOULD MAINLY BE MVFR SUN MORNING...BUT COULD FALL
TO IFR AT TIMES.
&&
.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...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
424 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 THROUGH FRIDAY)
ISSUED AT 401 AM EDT SAT APR 23 2016
LOOKS LIKE THE CHILLY...ACTIVE WX PATTERN IS STILL ON TRACK FOR LATE
THIS WEEKEND INTO EARLY NEXT WEEK AS A VERY TIGHT BAROCLINIC ZN WL
SETUP ACRS THE UPR GREAT LKS NEAR THE CONFLUENCE ZN BTWN NRN BRANCH
NW FLOW IN CANADA AND AN ACTIVE SRN BRANCH WSW 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 AND MOISTER AIR TO THE S. 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 NW UPR MI FM LATE SUN NGT INTO MON NGT. BUT AS IS ALWAYS THE CASE
WHEN AN AREA IS NEAR THE NRN EDGE OF A PCPN AREA WITH PLENTY OF DRY
AIR JUST TO THE N...SMALL CHANGES IN THE FCST PARAMETERS MAY HAVE A
SGNFT IMPACT ON THE OUTCOME. AS THE ONTARIO HI PRES BLDS INTO THE
UPR LKS ON TUE...EXPECT QUITE BUT STILL RELATIVELY CHILLY WX INTO
MID WEEK. ANOTHER DISTURANCE/LO PRES MOVING NE FM THE PLAINS MAY
BRING MORE PCPN LATER WED/THU...BUT THERE IS GREAT UNCERTAINTY AS TO
WHETHER THE NW FLOW ALOFT ARND A DEEP UPR TROF CENTERED IN QUEBEC WL
SHUNT THIS SYSTEM TO THE S. THIS PERSISTENT DEEP TROF WL MAINTAIN
BLO NORMAL TEMPS FOR UPR MI THRU THIS WEEK.
SUN/MON...UPR MI IS FCST TO BE UNDER SHARP BAROCLINIC ZN UNDER
CONFLUENCE ZN BTWN COLD NRN BRANCH NW FLOW DOMINATING QUEBEC AND A
SRN BRANCH WSW FLOW OVER THE NRN CONUS. ALTHOUGH THE CONFLUENT UPR
FLOW WELL TO THE NE OF SLOW MOVING...STRONGER SRN BRANCH SHRTWV
RIDING ENEWD THRU THE NRN PLAINS WL TEND TO SHEAR OUT/WEAKEN THAT
SHRTWV AND OTHER DISTURBANCES THAT EJECT OUT AHEAD OF IT...MOST OF
THE MEDIUM RANGE MODELS GENERATE SOME MDT TO HEAVY PCPN OVER MAINLY
THE S HALF OF THE CWA. WAA TO THE N OF THE FNT...UPR DVGC IN RRQ OF
120KT H3 JET MAX JUST S OF JAMES BAY AS WELL AS SHARP...PERSISTENT
LO-MID LVL FGEN N OF THE H85 WARM/STNRY FNT STRETCHING E ACRS WI FM
LO IN THE NRN PLAINS AND AXIS OF PWAT AOA AN INCH /ABOUT 225 PCT OF
NORMAL/ OVER THE SRN CWA LOOK TO BE THE ENHANCEMENT FACTORS THAT WL
SUPPORT THIS HEAVIER PCPN AND OVERCOME THE NEGATIVES ASSOCIATED WITH
THE UPR CONFLUENCE. SOME OF THE MODELS SHOW AS MUCH AS 2-3 INCHES OF
PCPN FALLING OVER PORTIONS OF THE CWA DURING THE SUN THRU MON TIME.
SOME OF THE COLDER MODELS` FCST SDNGS/THERMAL FIELDS WITH H85 TEMPS
FALLING BLO 0C INDICATE AT LEAST SOME OF THE PCPN NEAR THE NRN EDGE
OF THE PCPN AREA WL FALL IN THE FORM OF SN AT TIMES. HOWEVER...
GUIDANCE HAS BEEN INCONSISTENT ON THE DEGREE OF COOLING AS WELL AS
THE IMPACT OF MUCH DRIER AIR THAT WL BE PRESENT JUST TO THE N AND
COULD ADVECT INTO THE CWA IN THE STEADY NNE FLOW TO THE S OF HI PRES
BLDG INTO NW ONTARIO. BEST CHC FOR SOME DRYING THAT MAY LIMIT
POPS/QPF AT LEAST TEMPORARILY LOOKS TO BE LATER ON SUN IN THE WAKE
OF A SHEARING DISTURBANCE PASSING TO THE E. THE BEST CHC FOR SOME
ACCUMULATING SN WL BE LATE SUN NGT INTO MON MRNG OVER THE HIER
TERRAIN OF THE W HALF WHEN THE SLOWLY APRCHG MAIN SHRTWV WL ENHANCE
UVV/DYNAMIC COOLING IN THE ABSENCE OF SOLAR WARMING...UNLESS LLVL
DRYING FM THE N NEGATIVELY IMPACTS PCPN POTENTIAL. NOT OUT OF THE
QUESTION THERE COULD BE A COUPLE INCHES OF WET...HEAVY SN IN THESE
AREAS. TEMPS THRU THIS TIME WL RUN BLO TO WELL BLO NORMAL...
ESPECIALLY THE MAX TEMPS.
MON NGT...AS THE SHRTWV RIDING TO THE NE BEGINS TO SHEAR OUT TO THE
ESE...LARGER SCALE DVNA/MID LVL DRYING/DEEP LYR QVECTOR DVGC IN ITS
WAKE WL TEND TO DIMINISH LINGERING PCPN NW-SE. WITH THE ARRIVAL OF
DRIER LLVL AIR ASSOCIATED WITH THE ONTARIO HI BLDG TOWARD THE UPR
LKS...SKIES MAY CLR OUT AS WELL AND ALLOW MIN TEMPS TO FALL WELL
INTO THE 20S.
TUE/TUE NGT...AS THE ONTARIO HI PRES EXPANDS INTO THE UPR LKS UNDER
CONFLUENT NW FLOW ALF BTWN DEEP UPR LO OVER QUEBEC AND AN APRCHG RDG
SHIFTING E THRU THE NRN PLAINS...EXPECT MOCLR SKIES. H85 TEMPS
RECOVERING TO NEAR 0C AND PLENTY OF SUNSHINE SHOULD ALLOW MAX TEMPS
TO RECOVER AT LEAST CLOSE TO 50 AWAY FM THE COOLING INFLUENCE OF THE
LKS. TUE NGT IS LIKELY TO BE ANOTHER CHILLY ONE WITH THE HI PRES
STILL DOMINATING.
WED/THU...ATTENTION WL THEN TURN TO WHETHER ANOTHER SRN BRANCH
SHRTWV MOVING NE THRU THE PLAINS WL IMPACT THE CWA DURING THE MID
WEEK. HOW FAR NE THIS DISTURBANCE/ACCOMPANYING PCPN WL MOVE WL
DEPEND ON THE STRENGTH OF THE PERSISTENT...DEEP CLOSED LO IN QUEBEC.
ALTHOUGH MANY OF THE MEDIUM RANGE MODELS BRING ASSOCIATED PCPN INTO
THE UPR LKS...SUSPECT THE DRIER RECENT CNDN MODELS ARE ON THE RIGHT
TRACK WITH A MORE CONFLUENT NW FLOW THRU ONTARIO ALLOWING A MORE
PERSISTENT SFC HI PRES RDG TO INFLUENCE THE UPR LKS AS SUGGESTED BY
THE 12Z GFS ENSEMBLE MEAN. BUT WL FOLLOW MODEL CONSENSUS GIVEN THE
MODEL SPREAD SO FAR OUT IN THE FCST PERIOD.
FRI...UPR RDGING/SFC HI PRES BLDG INTO THE UPR LKS WL BRING A RETURN
OF DRY AND SEASONABLE WX. WITH H85 TEMPS FCST WITHIN A FEW DEGREES
OF 0C...BLO NORMAL TEMPS WL CONTINUE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 139 PM EDT SAT APR 23 2016
VFR CONDITIONS WILL LIKELY HOLD ON THRU THE EVENING AT
KIWD/KCMX/KSAW UNDER ONLY BKN-OVC MID LEVEL CLOUDS. LIGHT RAIN WILL
ARRIVE TONIGHT AND CONTINUE THRU SUN. CIGS WILL BEGIN TO STEADILY
LOWER OVERNIGHT AS STEADIER RAIN ARRIVES...REACHING IFR AT ALL
TERMINALS AROUND 12Z. CONDITIONS MAY CONTINUE TO DETERIORATE FURTHER
TO LIFR DURING THE MORNING HRS...PARTICULARLY AT KCMX/KSAW UNDER
UPSLOPE WINDS. VIS SHOULD MAINLY BE MVFR SUN MORNING...BUT COULD FALL
TO IFR AT TIMES.
&&
.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...KC
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
131 AM EDT SAT APR 23 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 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 130 AM EDT SAT APR 23 2016
VFR CONDITIONS WILL CONTINUE FOR THE ENTIRE FORECAST PERIOD. LIGHT
RAIN WILL MOVE IN FOR SAT EVENING AND WILL START TO LOWER CLOUD
HEIGHTS THEN.
&&
.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...07
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
658 PM CDT SUN APR 24 2016
.UPDATE...
ISSUED AT 648 PM CDT SUN APR 24 2016
UPDATED AVIATION DISCUSSION BELOW FOR THE 00Z TAF ISSUANCE.
&&
.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 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 648 PM CDT SUN APR 24 2016
SURFACE LOW IN SOUTH DAKOTA WITH A FRONTAL BOUNDARY DRAPED WEST
TO EAST ACROSS THE FORECAST AREA. SITES TO THE NORTH OF THAT
BOUNDARY ARE SOCKED IN WITH IFR OR EVEN LIFR CIGS AND IT WILL
REMAIN THAT WAY ALL NIGHT AND THROUGH AT LEAST PART OF MONDAY.
THIS INCLUDES AXN...STC...AND POSSIBLY RNH. MSP IS SITTING ON THE
EDGE OF VFR CIGS TO THE SOUTH...AND MVFR/IFR JUST TO THE NORTH.
WENT WITH VFR THROUGH ABOUT 04Z...THEN EXPECT THE LOW STRATUS TO
SAG SOUTH AND TAKE OVER. RWF IS FAR ENOUGH SOUTH THAT VFR IS
POSSIBLE THROUGH THE PERIOD. SHOWERS AND THUNDERSTORMS ARE MOVING
INTO SOUTHWESTERN MN AND WILL CONTINUE TO MOVE NORTHEAST...BUT
WEAKEN WITH TIME. BY THE TIME THEY REACH THE METRO AREA...THEY
WILL HAVE WEAKENED CONSIDERABLY...AND OVERNIGHT MOSTLY SCATTERED
SHOWERS WITH ISOLATED RUMBLES OF THUNDER WILL BE LIKELY
INITIALLY...BUT AS THE NIGHT GOES ON LOOK FOR A TRANSITION TO JUST
SCATTERED SHOWERS.
KMSP...STILL THINKING CIGS GO DOWN OVERNIGHT...BUT SOME HI-RES
GUIDANCE WANTS TO KEEP MSP JUST BARELY ON THE VFR SIDE OF THE
BOUNDARY INTO TOMORROW MORNING. FEEL THAT IS UNLIKELY AT THIS
TIME...AND SHOULD HAVE AT LEAST MVFR AND POSSIBLY IFR COME IN
TONIGHT AND REMAIN IN PLACE FOR MUCH OF MONDAY.
/OUTLOOK FOR KMSP/
TUE...VFR. WINDS E 10-15KTS.
WED...MVFR LATE IN THE DAY. SHRA LIKELY. WIND E 15-25KTS.
THU...MVFR PSBL. CHANCE OF SHRA. WIND E 10-15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
UPDATE...SPD
SHORT TERM...RAH
LONG TERM...CLF
AVIATION...SPD
AREA FORECAST DISCUSSION
NWS DULUTH MN
1254 PM CDT SAT APR 23 2016
.UPDATE...
ISSUED AT 1034 AM CDT SAT APR 23 2016
UPDATED THE FORECAST THROUGH EARLY SUNDAY...MAINLY FOCUSING ON THE
TIMING OF THE PRECIPITATION. LEANED ON THE EXPERIMENTAL HRRR AND
RAP13 FOR THE BLEND BECAUSE THE TWO MODELS WERE PERFORMING THE
BEST WITH WHAT WAS OCCURRING EARLIER THIS MORNING. BOTH THE HRRR
AND RAP13 WERE REFLECTING THE BAND OF SHOWERS ACROSS THE WEST
CENTRAL FORECAST AREA...THEN LIFTING THE BAND NORTH AND EAST INTO
THIS AFTERNOON. MUCH OF THE PCPN THIS AFTERNOON SHOULD BE LIMITED
TO FAR NORTHERN MINNESOTA...AND THEN ONLY BEGIN TO SPREAD INTO THE
REST OF THE NORTHLAND LATE TODAY.
THE PREVIOUS FORECAST HAD SLEET AND FREEZING RAIN OVER THE
ARROWHEAD TONIGHT AND EARLY SUNDAY. HOWEVER...THE LATEST
RAP13/NAM12/GFS20 MODEL SOUNDINGS HEAVILY FAVOR ONLY RAIN OR
SNOW...SO REMOVED THE SLEET AND FREEZING RAIN. THE PREVIOUS
FORECAST ALSO HAD A MIXTURE OF RAIN AND SNOW FOR THE LAKE SUPERIOR
AREA SUNDAY AFTERNOON...BUT THE TEMPERATURES ALOFT HEAVILY SUPPORT
RAIN. WHILE COLD NEAR SURFACE TEMPERATURES MAY APPROACH THE
FREEZING MARK...THE RELATIVELY WARM TEMPERATURES ALOFT SHOULD
ENSURE THE FALLING PCPN REMAINS RAIN.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 401 AM CDT SAT APR 23 2016
THE SHORT TERM FORECAST FOCUS WILL BE ON PRECIPITATION CHANCES/TYPE
THROUGH SUNDAY.
A SURFACE LOW IN EASTERN MONTANA IS FORECAST TO MOVE SOUTHEAST INTO
SOUTH DAKOTA BY 12Z SUNDAY THEN MOVE ONLY SLOWLY EAST ON SUNDAY.
MOISTURE WILL SURGE INTO THE NORTHLAND TODAY INTO SUNDAY WITH PWAT
VALUES INCREASING FROM A THIRD TO HALF INCH OVER THE AREA THIS
MORNING...TO THREE QUARTERS TO NEAR AN INCH AND A QUARTER BY 12Z
SUNDAY. PERSISTENT WAA/FGEN AS WELL AS SHORTWAVE ENERGY TODAY INTO
SUNDAY WILL CAUSE PRECIPITATION TO INCREASE ACROSS THE NORTHLAND.
PRECIPITATION WILL BECOME WIDESPREAD TONIGHT INTO SUNDAY. A
STRONG GRADIENT WITH PRESSURE FALLS OFF TO THE SOUTHWEST WILL
CAUSE THE WIND TO INCREASE AROUND LAKE SUPERIOR...WITH STRONG
WINDS OVER AND CLOSE TO LAKE SUPERIOR DEVELOPING LATER TONIGHT
INTO MONDAY.
PRECIPITATION TYPE WILL BE A CHALLENGE OVER PORTIONS OF THE
NORTHLAND...MAINLY TONIGHT INTO SUNDAY IN THE ARROWHEAD TO THE HEAD
OF LAKE SUPERIOR. JUST SHOWERS ARE EXPECTED TODAY AS THE BOUNDARY
LAYER WARMS...BUT TONIGHT THE LOW LEVELS WILL COOL AROUND PORTIONS
OF LAKE SUPERIOR AND WITH INCREASING EAST/NORTHEAST
WINDS...ADDITIONAL COOLING CAN BE EXPECTED AROUND THE LAKE. FORECAST
SOUNDINGS AND SURFACE TEMPERATURES SUGGEST A MIX FROM RAIN OR SNOW
TO SLEET OR EVEN SOME FREEZING RAIN WILL BE POSSIBLE LATER TONIGHT
INTO SUNDAY MORNING OVER PORTIONS OF THE ARROWHEAD. AT THIS
TIME...IT LOOKS LIKE TEMPERATURES THROUGH SUNDAY MORNING WILL REMAIN
WARM ENOUGH FOR JUST RAIN IN THE TWIN PORTS AND SOUTH SHORE AREAS. A
MIX MAY DEVELOP LATE SUNDAY AFTERNOON/EVENING AT THE HEAD OF LAKE
SUPERIOR AS STRONG EASTERLY FLOW AND PERSISTENT RAIN COOLS SURFACE
TEMPERATURES IN THOSE AREAS. AT THIS TIME...SIGNIFICANT ICE IS NOT
EXPECTED...BUT IF SURFACE TEMPERATURES HAPPEN TO COOL ABOUT 2 OR 3
DEGREES MORE THAN EXPECTED...THERE COULD BE SOME ICING THAT DEVELOPS.
SIGNIFICANT RAINFALL IS EXPECTED THROUGH MONDAY...WITH AMOUNTS
RANGING FROM A THIRD OF AN INCH ALONG THE INTERNATIONAL BORDER...TO
1.5 TO 2.5 INCHES FROM THE TWIN PORTS AND OVER NORTHERN WISCONSIN.
WE EXPECT HIGHS TODAY TO RANGE FROM THE LOWER TO MID SIXTIES IN THE
BRAINERD LAKES INTO NORTHWEST WISCONSIN...TO THE LOWER FIFTIES OVER
FAR NORTHERN MINNESOTA. INCREASING WINDS OFF OF LAKE SUPERIOR WILL
KEEP ALL AREAS AROUND THE LAKE MUCH COOLER...WITH ONLY LOWER TO MID
FORTIES EXPECTED. SUNDAY WILL BE EVEN COOLER WITH STRONGER WINDS.
THE LAKE INFLUENCE WILL BE FELT WELL INLAND TO MOOSE LAKE...SOLON
SPRINGS AND IRON RIVER...AND WELL INTO THE ARROWHEAD. TEMPERATURES
HERE WILL ONLY BE IN THE THIRTIES...WITH MID FORTIES TO LOWER
FIFTIES ELSEWHERE.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 401 AM CDT SAT APR 23 2016
PRECIPITATION WILL CONTINUE SUNDAY NIGHT AND MONDAY WITH THE STRONG
SURFACE LOW SLOWLY MOVING FROM CENTRAL SOUTH DAKOTA...EAST TO
NORTHWEST IOWA BY EARLY MONDAY MORNING AND ON TO NORTHWEST ILLINOIS
BY MONDAY EVENING. STRONG FRONTOGENESIS AND ISENTROPIC LIFT WILL
CONTINUE ACROSS THE SOUTHERN HALF OF THE FORECAST AREA SUNDAY NIGHT
THROUGH MONDAY. FOR NOW...IT APPEARS THE GREATEST POPS SHOULD BE
SUNDAY NIGHT...GRADUALLY DIMINISHING THROUGH MONDAY. EASTERLY FLOW
OFF LAKE SUPERIOR AND COLDER...DRIER AIR MOVING IN FROM THE AREA
FROM THE NORTHEAST MAY TURN THE PRECIPITATION OVER TO A WINTRY MIX
ALONG THE NORTH SHORE OR FARTHER INLAND NORTH OF THE IRON RANGE.
SURFACE TEMPERATURES WILL BE CRITICAL DURING THIS TIME RANGE...AND
THERE IS SOME POTENTIAL FOR FREEZING RAIN. HAVE LEFT THE FREEZING
RAIN OUT OF THE FORECAST FOR THESE PERIODS FOR NOW...BUT WILL HAVE
TO RE-EVALUATE THIS OVER THE NEXT DAYS. MONDAY NIGHT THE
PRECIPITATION WILL GRADUALLY END FROM WEST TO EAST...LEAVING DRY
CONDITIONS FOR TUESDAY...WITH WARMER CONDITIONS FOR TUESDAY THAN
MONDAY.
TUESDAY NIGHT THROUGH FRIDAY THERE ARE SOME SIGNIFICANT DIFFERENCES
IN THE MODELS. A STRONG UPPER LOW OVER THE PLAINS WILL GRADUALLY
MOVE EAST THROUGH THE PERIOD...WITH THE GFS KEEPING THE LOW TIGHTER
AND FARTHER TO THE NORTH THAN THE MORE OPEN AND FASTER MOVING ECMWF.
THE GFS SOLUTION KEEPS PRECIPITATION GOING OVER THE FORECAST AREA
WEDNESDAY THROUGH THURSDAY NIGHT...WHERE THE ECMWF KEEPS US DRY
THROUGH MUCH OF THE PERIOD WITH THE UPPER LOW TOO FAR NORTH TO
AFFECT US. THIS FARTHER NORTH GFS SOLUTION IS RELATIVELY NEW...AS
PREVIOUS SOLUTIONS ALSO KEPT THIS UPPER LOW TOO FAR SOUTH TO AFFECT
THE FORECAST AREA. HAVE KEPT TO THE BLENDED SOLUTION FOR POPS...BUT
WE MAY BE ABLE TO LOWER THEM AGAIN. TEMPERATURES GRADUALLY WARM
THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1245 PM CDT SAT APR 23 2016
VFR CONDITIONS TODAY WILL GIVE WAY TO LOWERING CEILINGS THIS
EVENING...AND SHOWERS WITH WIDESPREAD MVFR CONDITIONS AFTER 06Z.
THUNDER IS POSSIBLE FOR KBRD...KDLH AND KHYR OVERNIGHT. ALTHOUGH
HAVE LEFT OUT OF THE TAF FOR NOW DUE TO UNCERTAINTIES IN COVERAGE
AND TIMING. WINDS WILL INCREASE OUT OF THE EAST SUNDAY WITH
FREQUENT GUSTS AROUND 25 KNOTS. WINDS WILL BE STRONGER NEAR LAKE
SUPERIOR.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 48 35 37 32 / 10 80 80 90
INL 52 36 50 30 / 60 70 10 10
BRD 65 44 45 37 / 20 70 70 90
HYR 62 46 50 38 / 0 70 90 90
ASX 55 39 41 35 / 10 80 90 90
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...GALE WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON FOR
LSZ140>147.
SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 10 AM CDT
SUNDAY FOR LSZ143>146.
&&
$$
UPDATE...GROCHOCINSKI
SHORT TERM...MELDE
LONG TERM...LE
AVIATION...GRANING
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1034 AM CDT SAT APR 23 2016
.UPDATE...
ISSUED AT 1034 AM CDT SAT APR 23 2016
UPDATED THE FORECAST THROUGH EARLY SUNDAY...MAINLY FOCUSING ON THE
TIMING OF THE PRECIPITATION. LEANED ON THE EXPERIMENTAL HRRR AND
RAP13 FOR THE BLEND BECAUSE THE TWO MODELS WERE PERFORMING THE
BEST WITH WHAT WAS OCCURRING EARLIER THIS MORNING. BOTH THE HRRR
AND RAP13 WERE REFLECTING THE BAND OF SHOWERS ACROSS THE WEST
CENTRAL FORECAST AREA...THEN LIFTING THE BAND NORTH AND EAST INTO
THIS AFTERNOON. MUCH OF THE PCPN THIS AFTERNOON SHOULD BE LIMITED
TO FAR NORTHERN MINNESOTA...AND THEN ONLY BEGIN TO SPREAD INTO THE
REST OF THE NORTHLAND LATE TODAY.
THE PREVIOUS FORECAST HAD SLEET AND FREEZING RAIN OVER THE
ARROWHEAD TONIGHT AND EARLY SUNDAY. HOWEVER...THE LATEST
RAP13/NAM12/GFS20 MODEL SOUNDINGS HEAVILY FAVOR ONLY RAIN OR
SNOW...SO REMOVED THE SLEET AND FREEZING RAIN. THE PREVIOUS
FORECAST ALSO HAD A MIXTURE OF RAIN AND SNOW FOR THE LAKE SUPERIOR
AREA SUNDAY AFTERNOON...BUT THE TEMPERATURES ALOFT HEAVILY SUPPORT
RAIN. WHILE COLD NEAR SURFACE TEMPERATURES MAY APPROACH THE
FREEZING MARK...THE RELATIVELY WARM TEMPERATURES ALOFT SHOULD
ENSURE THE FALLING PCPN REMAINS RAIN.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 401 AM CDT SAT APR 23 2016
THE SHORT TERM FORECAST FOCUS WILL BE ON PRECIPITATION CHANCES/TYPE
THROUGH SUNDAY.
A SURFACE LOW IN EASTERN MONTANA IS FORECAST TO MOVE SOUTHEAST INTO
SOUTH DAKOTA BY 12Z SUNDAY THEN MOVE ONLY SLOWLY EAST ON SUNDAY.
MOISTURE WILL SURGE INTO THE NORTHLAND TODAY INTO SUNDAY WITH PWAT
VALUES INCREASING FROM A THIRD TO HALF INCH OVER THE AREA THIS
MORNING...TO THREE QUARTERS TO NEAR AN INCH AND A QUARTER BY 12Z
SUNDAY. PERSISTENT WAA/FGEN AS WELL AS SHORTWAVE ENERGY TODAY INTO
SUNDAY WILL CAUSE PRECIPITATION TO INCREASE ACROSS THE NORTHLAND.
PRECIPITATION WILL BECOME WIDESPREAD TONIGHT INTO SUNDAY. A
STRONG GRADIENT WITH PRESSURE FALLS OFF TO THE SOUTHWEST WILL
CAUSE THE WIND TO INCREASE AROUND LAKE SUPERIOR...WITH STRONG
WINDS OVER AND CLOSE TO LAKE SUPERIOR DEVELOPING LATER TONIGHT
INTO MONDAY.
PRECIPITATION TYPE WILL BE A CHALLENGE OVER PORTIONS OF THE
NORTHLAND...MAINLY TONIGHT INTO SUNDAY IN THE ARROWHEAD TO THE HEAD
OF LAKE SUPERIOR. JUST SHOWERS ARE EXPECTED TODAY AS THE BOUNDARY
LAYER WARMS...BUT TONIGHT THE LOW LEVELS WILL COOL AROUND PORTIONS
OF LAKE SUPERIOR AND WITH INCREASING EAST/NORTHEAST
WINDS...ADDITIONAL COOLING CAN BE EXPECTED AROUND THE LAKE. FORECAST
SOUNDINGS AND SURFACE TEMPERATURES SUGGEST A MIX FROM RAIN OR SNOW
TO SLEET OR EVEN SOME FREEZING RAIN WILL BE POSSIBLE LATER TONIGHT
INTO SUNDAY MORNING OVER PORTIONS OF THE ARROWHEAD. AT THIS
TIME...IT LOOKS LIKE TEMPERATURES THROUGH SUNDAY MORNING WILL REMAIN
WARM ENOUGH FOR JUST RAIN IN THE TWIN PORTS AND SOUTH SHORE AREAS. A
MIX MAY DEVELOP LATE SUNDAY AFTERNOON/EVENING AT THE HEAD OF LAKE
SUPERIOR AS STRONG EASTERLY FLOW AND PERSISTENT RAIN COOLS SURFACE
TEMPERATURES IN THOSE AREAS. AT THIS TIME...SIGNIFICANT ICE IS NOT
EXPECTED...BUT IF SURFACE TEMPERATURES HAPPEN TO COOL ABOUT 2 OR 3
DEGREES MORE THAN EXPECTED...THERE COULD BE SOME ICING THAT DEVELOPS.
SIGNIFICANT RAINFALL IS EXPECTED THROUGH MONDAY...WITH AMOUNTS
RANGING FROM A THIRD OF AN INCH ALONG THE INTERNATIONAL BORDER...TO
1.5 TO 2.5 INCHES FROM THE TWIN PORTS AND OVER NORTHERN WISCONSIN.
WE EXPECT HIGHS TODAY TO RANGE FROM THE LOWER TO MID SIXTIES IN THE
BRAINERD LAKES INTO NORTHWEST WISCONSIN...TO THE LOWER FIFTIES OVER
FAR NORTHERN MINNESOTA. INCREASING WINDS OFF OF LAKE SUPERIOR WILL
KEEP ALL AREAS AROUND THE LAKE MUCH COOLER...WITH ONLY LOWER TO MID
FORTIES EXPECTED. SUNDAY WILL BE EVEN COOLER WITH STRONGER WINDS.
THE LAKE INFLUENCE WILL BE FELT WELL INLAND TO MOOSE LAKE...SOLON
SPRINGS AND IRON RIVER...AND WELL INTO THE ARROWHEAD. TEMPERATURES
HERE WILL ONLY BE IN THE THIRTIES...WITH MID FORTIES TO LOWER
FIFTIES ELSEWHERE.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 401 AM CDT SAT APR 23 2016
PRECIPITATION WILL CONTINUE SUNDAY NIGHT AND MONDAY WITH THE STRONG
SURFACE LOW SLOWLY MOVING FROM CENTRAL SOUTH DAKOTA...EAST TO
NORTHWEST IOWA BY EARLY MONDAY MORNING AND ON TO NORTHWEST ILLINOIS
BY MONDAY EVENING. STRONG FRONTOGENESIS AND ISENTROPIC LIFT WILL
CONTINUE ACROSS THE SOUTHERN HALF OF THE FORECAST AREA SUNDAY NIGHT
THROUGH MONDAY. FOR NOW...IT APPEARS THE GREATEST POPS SHOULD BE
SUNDAY NIGHT...GRADUALLY DIMINISHING THROUGH MONDAY. EASTERLY FLOW
OFF LAKE SUPERIOR AND COLDER...DRIER AIR MOVING IN FROM THE AREA
FROM THE NORTHEAST MAY TURN THE PRECIPITATION OVER TO A WINTRY MIX
ALONG THE NORTH SHORE OR FARTHER INLAND NORTH OF THE IRON RANGE.
SURFACE TEMPERATURES WILL BE CRITICAL DURING THIS TIME RANGE...AND
THERE IS SOME POTENTIAL FOR FREEZING RAIN. HAVE LEFT THE FREEZING
RAIN OUT OF THE FORECAST FOR THESE PERIODS FOR NOW...BUT WILL HAVE
TO RE-EVALUATE THIS OVER THE NEXT DAYS. MONDAY NIGHT THE
PRECIPITATION WILL GRADUALLY END FROM WEST TO EAST...LEAVING DRY
CONDITIONS FOR TUESDAY...WITH WARMER CONDITIONS FOR TUESDAY THAN
MONDAY.
TUESDAY NIGHT THROUGH FRIDAY THERE ARE SOME SIGNIFICANT DIFFERENCES
IN THE MODELS. A STRONG UPPER LOW OVER THE PLAINS WILL GRADUALLY
MOVE EAST THROUGH THE PERIOD...WITH THE GFS KEEPING THE LOW TIGHTER
AND FARTHER TO THE NORTH THAN THE MORE OPEN AND FASTER MOVING ECMWF.
THE GFS SOLUTION KEEPS PRECIPITATION GOING OVER THE FORECAST AREA
WEDNESDAY THROUGH THURSDAY NIGHT...WHERE THE ECMWF KEEPS US DRY
THROUGH MUCH OF THE PERIOD WITH THE UPPER LOW TOO FAR NORTH TO
AFFECT US. THIS FARTHER NORTH GFS SOLUTION IS RELATIVELY NEW...AS
PREVIOUS SOLUTIONS ALSO KEPT THIS UPPER LOW TOO FAR SOUTH TO AFFECT
THE FORECAST AREA. HAVE KEPT TO THE BLENDED SOLUTION FOR POPS...BUT
WE MAY BE ABLE TO LOWER THEM AGAIN. TEMPERATURES GRADUALLY WARM
THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 642 AM CDT SAT APR 23 2016
VFR CONDITIONS THIS MORNING ARE EXPECTED TO CONTINUE UNTIL
APPROXIMATELY 03Z THIS EVENING. AFTER 03Z AN AREA OF MVFR CEILINGS
WILL SPREAD INTO THE AREA FROM THE WEST WITH SCATTERED SHOWERS.
THESE CEILINGS WILL GRADUALLY LOWER TO IFR FOR KDLH...KHIB...KBRD
AND KHYR WITH MVFR VISIBILITIES IN LIGHT RAIN. KINL TO REMAIN
MVFR. THUNDER IS ALSO POSSIBLE FOR KBRD...KDLH AND KHYR AFTER 00Z
THIS EVENING...THOUGH HAVE LEFT OUT OF THE SPECIFIC TERMINAL
FORECAST FOR NOW DUE TO UNCERTAINTIES IN TIMING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 48 35 37 32 / 10 80 80 90
INL 52 36 50 30 / 60 60 10 10
BRD 65 44 45 37 / 40 70 70 90
HYR 62 46 50 38 / 0 70 90 90
ASX 55 39 41 35 / 10 80 90 90
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...GALE WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON FOR
LSZ140>147.
SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 10 AM CDT
SUNDAY FOR LSZ143>146.
&&
$$
UPDATE...GROCHOCINSKI
SHORT TERM...MELDE
LONG TERM...LE
AVIATION...LE
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
912 PM CDT SUN APR 24 2016
.UPDATE...
GENERALLY THE FCST IS ON TRACK. STILL EXPECT SOME PATCHY FOG IN THE
E/SE AS THE LOW LEVEL RETURN FLOW WILL BE THE LIGHTEST DUE TO THE
SFC RIDGE OVER THE AREA SLOWLY BUILDING E. HRRR IS NOT SHOWING MUCH
FOG BUT FCST SOUNDINGS INDICATE ENOUGH RADIATIONAL COOLING FOR SOME
PATCHY FOG AT BEST. WINDS ARE GENERALLY LIGHT BUT SOME MID/HIGH
LEVEL CLOUDINESS AND A LITTLE BIT OF SFC WINDS WILL KEEP THE LOWS
SLIGHTLY WARMER TONIGHT. ADJUSTED HOURLY TEMPS/DEWPOINT CURVES. REST
OF THE FCST LOOKS GOOD. /DC/
&&
.AVIATION...VFR CONDITIONS WILL CONTINUE OVERNIGHT FOR MOST
LOCATIONS. SOME PATCHY FOG WILL BE POSSIBLE GENERALLY ALONG AND
SOUTHEAST OF THE I59 CORRIDOR. SOME LOCALLY DENSE FOG MAY BE SEEN AT
HBG BETWEEN 10 AND 14Z. /26/
&&
.DISCUSSION... /ISSUED 319 PM CDT SUN APR 24 2016/
DISCUSSION...VERY PLEASANT WEATHER CONDITIONS CONTINUED TODAY AS
THE SURFACE RIDGE CONTINUED TO SHIFT EAST OF THE REGION AND LOW
LEVEL FLOW TURNED AROUND TO THE SOUTH. HIGH CLOUDS HAVE BEGUN TO
INCREASE AHEAD OF AN APPROACHING SHORTWAVE, CURRENTLY PROPAGATING
ALONG THE NW GULF COAST. WITH MOISTURE REMAINING FAIRLY LIMITED, THIS
FEATURE IS NOT EXPECTED TO RESULT IN PRECIP AS IT PUSHES PAST OUR
AREA. MOSTLY DRY CONDITIONS ARE EXPECTED TO PERSIST INTO THE
BEGINNING OF THE NEW WORK WEEK AS SHORTWAVE MID/UPPER LEVEL RIDGING
BUILDS MONDAY INTO TUESDAY.
WITH THE POTENTIAL FOR CLOUDS AROUND AND A SOUTHERLY BREEZE
PERSISTING IN SOME AREAS OVERNIGHT, IT IS NOT EXPECTED TO BE QUITE AS
COOL AS IT WAS THIS MORNING. HOWEVER, THE EASTERN HALF OF THE AREA
SEEMS TO HAVE THE GREATEST POTENTIAL FOR CALM/LIGHT WIND...SO MIN
TEMPS WERE TRENDED A BIT COOLER IN THAT AREA. THERE COULD ALSO BE
SOME PATCHY FOG DEVELOPMENT, AND GUIDANCE SUGGESTS THE SOUTHEASTERN
QUADRANT OF THE AREA IS THE MOST LIKELY LOCATION FOR THIS TO OCCUR.
WITH DEEP LAYER MOISTURE GRADUALLY RETURNING TO THE AREA, THERE MAY
BE SUFFICIENT INSTABILITY FOR ISOLATED CONVECTION OVER THE SOUTHWEST
TOMORROW AND ACROSS THE ENTIRE AREA BY TUESDAY. THIS ACTIVITY IS
EXPECTED TO BE DIURNAL IN NATURE, SO FORECAST POPS WERE LIMITED TO
THE DAYTIME HOURS. OTHERWISE, EXPECT CONTINUED ABOVE NORMAL
TEMPERATURES WITH MOST LOCALES REMAINING DRY THROUGH TUESDAY. /DL/
LONG TERM...DURING THE PERIOD A GENERAL RIDGING PATTERN IS EXPECTED
WITH BETTER STORM ENERGY BEING DEFLECTED TO THE NORTH. THIS WILL
BRING WARMER THAN NORMAL TEMPERATURES AND RAIN CHANCES THROUGH MOST
OF THE LONG TERM PERIOD. ENSEMBLE GUIDANCE CONTINUES TO SHOW SOME
ANOMALOUS WARM LOW LEVEL TEMPS FOR NEXT WEEK. MODELS AND ENSEMBLES
WERE GENERALLY SIMILAR WITH THE UPPER PATTERN.
FOR WEDNESDAY THE CLOSED MID-UPPER LOW WILL LIFT INTO THE CENTRAL
AND NORTHERN PLAINS. IT WILL PUSH AGAINST THE NARROW MID-UPPER
RIDGE OVER THE MS VALLEY. THE ASSOCIATED COLD FRONT WILL PUSH
THROUGH THE PLAINS TOWARD THE REGION. PWATS WILL INCREASE TO AROUND
1.3-1.5 INCHES. THE MIDLEVEL RIDGE AXIS WILL PUSH EAST OF THE CWA.
MOISTURE TRANSPORT AND DAYTIME HEATING WILL BRING SOME SCATTERED
CONVECTION TO THE REGION FOR WEDNESDAY INTO WEDNESDAY NIGHT. SOME OF
THE MODELS INDICATE SOME STRONG THUNDERSTORM POTENTIAL AS THE COLD
FRONT APPROACHES THE REGION. THE GFS SHOWS LAPSE RATES WILL BE
AROUND 7-8C...SHOWALTER INDEXES WILL BE AROUND -6...AND CAPES ABOVE
2500 J/KG...WHICH WILL RESULT IN SOME STRONG INSTABILITY. SPC HAS A
15% SEVERE RISK JUST NORTHWEST OF THE REGION. SO FOR RIGHT NOW WILL
HOLD OFF IN PUTTING A LIMITED RISK IN THE HWO FOR THE DELTA REGION
FOR NOW...SINCE THE EURO DOES NOT SHOW SUCH STRONG PARAMETERS.
BY THURSDAY MORNING THE EURO MODEL WAS A LITTLE FASTER THAN THE
GEM/GFS IN PUSHING THE FRONT INTO ASHLEY COUNTY BY 12Z. MEANWHILE
ANOTHER CLOSED UPPER LOW WILL BE DEVELOPING OVER THE WESTERN CONUS.
MANUAL PROGS WERE A LITTLE FASTER IN BRINGING THE FRONT FARTHER INTO
THE NORTHWEST ON EARLY THURSDAY. DAYTIME HEATING AND THE APPROACHING
FRONT WILL BRING SCATTERED CONVECTION DURING THE DAY...WHICH WILL
BECOME ISOLATED IN THE EVENING. PWATS WILL INCREASE TO AROUND 1.8
INCHES. FOR FRIDAY THE FRONTAL BOUNDARY WILL BECOME STATIONARY NORTH
OF THE REGION. THE WESTERN US UPPER TROUGH WILL PIVOT TOWARD BAJA
WHICH WILL AMPLIFY THE MID-UPPER RIDGE OVER THE MS VALLEY. PWATS WILL
STAY AT AROUND 1.5 INCHES. CONVECTION WILL REMAIN ISOLATED TO
SCATTERED ON FRIDAY ACROSS THE REGION. AS WE MOVE INTO SATURDAY THE
FRONTAL BOUNDARY WILL EASE DOWN INTO THE CWA DURING THE DAY AND WILL
BECOME STATIONARY. THE BOUNDARY COMBINED WITH DAYTIME HEATING WILL
BECOME THE FOCUS FOR SOME SCATTERED CONVECTION. OUR RAIN CHANCES WILL
CONTINUE THROUGH EARLY THE FOLLOWING WEEK.
AS FAR AS TEMPS ARE CONCERNED HIGHS WILL BE WELL INTO THE 80S ON
MOST DAYS AND LOWS WILL BE IN THE 60S THROUGH THE PERIOD. WENT A FEW
DEGREES ABOVE SUPERBLEND FOR AFTERNOON HIGHS GOING TOWARD A BLEND OF
WPC AND MOS GUIDANCE. THE REST OF TEMPS WERE GENERALLY WITH THE
SUPERBLEND. MADE SOME SLIGHT POPS ADJUSTMENTS TO SUPERBLEND./17/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 58 83 64 86 / 2 8 8 22
MERIDIAN 54 82 63 85 / 0 3 5 22
VICKSBURG 63 83 67 85 / 1 14 8 20
HATTIESBURG 57 84 63 85 / 6 6 7 23
NATCHEZ 61 82 67 84 / 5 23 12 22
GREENVILLE 62 82 67 83 / 0 3 6 18
GREENWOOD 60 83 65 85 / 0 2 5 21
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DC/17/26
Area Forecast Discussion...Updated
National Weather Service Saint Louis MO
909 PM CDT SUN APR 24 2016
.UPDATE...
Issued at 909 PM CDT Sun Apr 24 2016
Still expect only a slight chance of showers and thunderstorms
over central and northeast Missouri through the rest of tonight.
The latest runs of the RAP continue to show a mid level trough
shearing out at the same time that the low level moisture
convergence weakens. This should cause the thunderstorms now over
far northwestern Missouri and eastern Kansas to begin to weaken.
This is confirmed based on the latest CAMS reflectivity. We
should still see some convective debris cloudiness over at least
the northern part of the CWA after midnight, and southerly winds
should not go light tonight because of the pressure gradient. Only
made minor changes to going lows based on current temperature
trends.
Britt
&&
.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 00z TAFs through 00z Monday Evening)
Issued at 622 PM CDT Sun Apr 24 2016
Thunderstorms over eastern Kansas are expected to weaken and stay northwest
of the terminals. Dry and VFR conditions are expected through the terminals.
Southerly winds will likely gust to around 20kts at times on Monday.
Specifics for KSTL: Dry and VFR conditions are expected over the
30 hours. Southerly winds will likely gust to around 20kts at
times on Monday.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1237 PM CDT SAT APR 23 2016
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 320 AM CDT SAT APR 23 2016
THE PRIMARY FCST CONCERNS CONTINUE TO BE TSTM CHANCES FROM TONIGHT
INTO MONDAY AND TEMPS.
UPPER AIR CHARTS FROM LAST EVENING HAD THE FOLLOWING FEATURES OF
INTEREST. AT 850 MB...A RIDGE WAS IN PLACE FROM TX INTO MN. MOISTURE
AT THIS LEVEL WAS MAINLY CONFINED TO SOUTH TEXAS AND THE GULF
COASTAL REGION. A RIDGE WAS ALSO IN ABOUT THE SAME AREA AT 700 MB
...WITH A TROUGH TO THE WEST. AT 500 MB...A TROUGH WAS OVER THE
WRN UNITED STATES...WITH 12 HOUR HEIGHT FALLS OF UP TO 90 METERS
AT KOAK IN CA. A JET MAX OF AROUND 110 KTS WAS STILL OUT OVER THE
PACIFIC AT 300 MB...ON THE BACKSIDE OF THE TROUGH. LATEST WATER
VAPOR AND IR STLT IMAGERY SHOWED JUST SOME CIRRUS LOCALLY...WITH
AREAS OF FOG TO THE EAST IN IA AND THICKER MID LEVEL CLOUDS OVER
THE ROCKIES. AT THE SFC...A RIDGE WAS TO OUR EAST AND A TROUGH TO
THE WEST...FROM ERN MT INTO ERN CO. S OR SE WINDS WERE NOTED WITH
DEWPOINTS IN THE 40S. THE KOAX SOUNDING FROM LAST EVENING ONLY HAD
ABOUT 0.33 PW. THERE WAS SOME BETTER MOISTURE TO OUR S.
TODAY...WILL PROBABLY KEEP THE FCST DRY. THE 00Z NAM AND EVEN SOME
RECENT RAP MODEL RUNS TRIED TO DVLP ISOLD LGT PCPN OVER PARTS OF
THE AREA THIS MORNING. 06Z NAM AND MOST OF THE RECENT EXPERIMENTAL
HRRR RUNS DID NOT SHOW ANY PCPN. AS THE PRES GRADIENT TIGHTENS
TODAY...IT WILL BECOME BREEZY OR WINDY. PREVIOUS FCST HIGHS LOOKED
PRETTY GOOD...MAINLY 75 TO 80...SO CHANGES WERE MINOR.
PCPN CHANCES WILL BE INCREASING TONIGHT. GENLY FELT THAT MUCH OF
THE EVENING WOULD BE DRY...DESPITE SOME PCPN SHOWN BY THE GFS.
OTHER MODELS KEEP BEST PCPN CHANCES W OF OUR AREA UNTIL AFTER
MIDNIGHT. POPS MAINLY FROM 20-30 PCT SEEM PRUDENT BASED ON THE
MOISTURE RETURN AND FORCING. TREND SHOULD BE FOR PCPN TO TRY TO
DIE OUT SUN MORNING...THEN REDEVELOP IN THE AFTN. THERE IS FAIRLY
GOOD MODEL AGREEMENT ON THAT. SPC DAY 2 OTLK SHOWS SLGT CHANCE OF
SVR AND BASED ON INSTABILITY AND SHEAR FCSTS...THAT LOOKS RIGHT.
BOUNDARY LAYER CAPE VALUES UP TO ABOUT 1500 J/KG SEEM PSBL. THE
HIGHEST TSTM CHANCES WILL BE ACRS ABOUT THE SERN 1/2 OF THE FCST
AREA. LOOK FOR LOWS TNGT 55 TO 60 AND HIGHS SUN MOSTLY MID OR
UPPER 70S.
A FRONT WILL MOVE DOWN THROUGH THE AREA MON...BUT LIFT LOOKS WEAK
SO HAVE KEPT POPS BELOW 15 PCT FOR NOW.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 320 AM CDT SAT APR 23 2016
WEAK HIGH PRES SHOULD BE OVER THE AREA MON NGT...WITH CONTINUED
DRY WEATHER. BUT...A CLOSED LOW WILL BE ORGANIZING TO OUR W/SW
MOST LIKELY OVER UT OR NRN AZ. THAT SHOULD MOVE OUT TO WRN KS BY
12Z WED...THEN PROBABLY INTO IA BY 12Z THU. YET ANOTHER CLOSED LOW
IS EXPECTED TO BE OVER SRN CA BY THU MORNING. MODEL AGREEMENT IS
NOT OVERLY GREAT BY FRI...BUT THE GENERAL CONSENSUS IS THAT THE
LOW WILL PROBABLY OPEN UP AND MOVE OUT INTO THE HIGH PLAINS BY THE
WEEKEND.
THE 00Z GFS WAS SLOWER BRINGING A CHANCE OF SHRA/TSTMS BACK TO THE
AREA ON TUE COMPARED TO THE ECMWF. GAVE BOTH MODELS EQUAL WEIGHT
FOR NOW. PCPN SHOULD BE FAIRLY WIDESPREAD TUE NGT/WED...WHICH MAY
HELP LIMIT STRONG STORM COVERAGE. CURRENT EXPECTED TIMING DRIES
THE AREA OUT FOR THE PD FROM THU INTO FRI MORNING...THEN PCPN IS
LIKELY TO RETURN.
&&
.AVIATION...(18Z TAFS FOR KOMA...KLNK...KOFK THROUGH 18Z SUNDAY)
ISSUED AT 1230 PM CDT SAT APR 23 2016
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE PERIOD. STRONG
SOUTH WINDS WILL CONTINUE ACROSS THE AREA THROUGH ABOUT 06Z AS LOW
PRESSURE OVER HIGH PLAINS OF MONTANA AND WYOMING TRACKS EAST
ACROSS SOUTH DAKOTA. A FEW ISOLATED THUNDERSTORMS POSSIBLE AFTER
06Z AS COLD FRONT MOVES INTO CENTRAL NEBRASKA.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
621 AM CDT SAT APR 23 2016
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 320 AM CDT SAT APR 23 2016
THE PRIMARY FCST CONCERNS CONTINUE TO BE TSTM CHANCES FROM TONIGHT
INTO MONDAY AND TEMPS.
UPPER AIR CHARTS FROM LAST EVENING HAD THE FOLLOWING FEATURES OF
INTEREST. AT 850 MB...A RIDGE WAS IN PLACE FROM TX INTO MN. MOISTURE
AT THIS LEVEL WAS MAINLY CONFINED TO SOUTH TEXAS AND THE GULF
COASTAL REGION. A RIDGE WAS ALSO IN ABOUT THE SAME AREA AT 700 MB
...WITH A TROUGH TO THE WEST. AT 500 MB...A TROUGH WAS OVER THE
WRN UNITED STATES...WITH 12 HOUR HEIGHT FALLS OF UP TO 90 METERS
AT KOAK IN CA. A JET MAX OF AROUND 110 KTS WAS STILL OUT OVER THE
PACIFIC AT 300 MB...ON THE BACKSIDE OF THE TROUGH. LATEST WATER
VAPOR AND IR STLT IMAGERY SHOWED JUST SOME CIRRUS LOCALLY...WITH
AREAS OF FOG TO THE EAST IN IA AND THICKER MID LEVEL CLOUDS OVER
THE ROCKIES. AT THE SFC...A RIDGE WAS TO OUR EAST AND A TROUGH TO
THE WEST...FROM ERN MT INTO ERN CO. S OR SE WINDS WERE NOTED WITH
DEWPOINTS IN THE 40S. THE KOAX SOUNDING FROM LAST EVENING ONLY HAD
ABOUT 0.33 PW. THERE WAS SOME BETTER MOISTURE TO OUR S.
TODAY...WILL PROBABLY KEEP THE FCST DRY. THE 00Z NAM AND EVEN SOME
RECENT RAP MODEL RUNS TRIED TO DVLP ISOLD LGT PCPN OVER PARTS OF
THE AREA THIS MORNING. 06Z NAM AND MOST OF THE RECENT EXPERIMENTAL
HRRR RUNS DID NOT SHOW ANY PCPN. AS THE PRES GRADIENT TIGHTENS
TODAY...IT WILL BECOME BREEZY OR WINDY. PREVIOUS FCST HIGHS LOOKED
PRETTY GOOD...MAINLY 75 TO 80...SO CHANGES WERE MINOR.
PCPN CHANCES WILL BE INCREASING TONIGHT. GENLY FELT THAT MUCH OF
THE EVENING WOULD BE DRY...DESPITE SOME PCPN SHOWN BY THE GFS.
OTHER MODELS KEEP BEST PCPN CHANCES W OF OUR AREA UNTIL AFTER
MIDNIGHT. POPS MAINLY FROM 20-30 PCT SEEM PRUDENT BASED ON THE
MOISTURE RETURN AND FORCING. TREND SHOULD BE FOR PCPN TO TRY TO
DIE OUT SUN MORNING...THEN REDEVELOP IN THE AFTN. THERE IS FAIRLY
GOOD MODEL AGREEMENT ON THAT. SPC DAY 2 OTLK SHOWS SLGT CHANCE OF
SVR AND BASED ON INSTABILITY AND SHEAR FCSTS...THAT LOOKS RIGHT.
BOUNDARY LAYER CAPE VALUES UP TO ABOUT 1500 J/KG SEEM PSBL. THE
HIGHEST TSTM CHANCES WILL BE ACRS ABOUT THE SERN 1/2 OF THE FCST
AREA. LOOK FOR LOWS TNGT 55 TO 60 AND HIGHS SUN MOSTLY MID OR
UPPER 70S.
A FRONT WILL MOVE DOWN THROUGH THE AREA MON...BUT LIFT LOOKS WEAK
SO HAVE KEPT POPS BELOW 15 PCT FOR NOW.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 320 AM CDT SAT APR 23 2016
WEAK HIGH PRES SHOULD BE OVER THE AREA MON NGT...WITH CONTINUED
DRY WEATHER. BUT...A CLOSED LOW WILL BE ORGANIZING TO OUR W/SW
MOST LIKELY OVER UT OR NRN AZ. THAT SHOULD MOVE OUT TO WRN KS BY
12Z WED...THEN PROBABLY INTO IA BY 12Z THU. YET ANOTHER CLOSED LOW
IS EXPECTED TO BE OVER SRN CA BY THU MORNING. MODEL AGREEMENT IS
NOT OVERLY GREAT BY FRI...BUT THE GENERAL CONSENSUS IS THAT THE
LOW WILL PROBABLY OPEN UP AND MOVE OUT INTO THE HIGH PLAINS BY THE
WEEKEND.
THE 00Z GFS WAS SLOWER BRINGING A CHANCE OF SHRA/TSTMS BACK TO THE
AREA ON TUE COMPARED TO THE ECMWF. GAVE BOTH MODELS EQUAL WEIGHT
FOR NOW. PCPN SHOULD BE FAIRLY WIDESPREAD TUE NGT/WED...WHICH MAY
HELP LIMIT STRONG STORM COVERAGE. CURRENT EXPECTED TIMING DRIES
THE AREA OUT FOR THE PD FROM THU INTO FRI MORNING...THEN PCPN IS
LIKELY TO RETURN.
&&
.AVIATION...(12Z TAFS FOR KOMA...KLNK...KOFK THROUGH 12Z SUNDAY)
ISSUED AT 619 AM CDT SAT APR 23 2016
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD WITH CHANGE
GROUPS DUE TO INCREASE IN SFC WINDS THROUGH THE DAY AND A GRADUAL
DECREASE THIS EVENING. WILL CONTINUE TO MONITOR AREAS OF FOG EAST
OF KOMA THIS MORNING AND SEND OUT UPDATES IF IT BEGINS TO MOVE
TOWARD THE MISSOURI RIVER VALLEY.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...KERN
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
320 AM CDT SAT APR 23 2016
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 320 AM CDT SAT APR 23 2016
THE PRIMARY FCST CONCERNS CONTINUE TO BE TSTM CHANCES FROM TONIGHT
INTO MONDAY AND TEMPS.
UPPER AIR CHARTS FROM LAST EVENING HAD THE FOLLOWING FEATURES OF
INTEREST. AT 850 MB...A RIDGE WAS IN PLACE FROM TX INTO MN. MOISTURE
AT THIS LEVEL WAS MAINLY CONFINED TO SOUTH TEXAS AND THE GULF
COASTAL REGION. A RIDGE WAS ALSO IN ABOUT THE SAME AREA AT 700 MB
...WITH A TROUGH TO THE WEST. AT 500 MB...A TROUGH WAS OVER THE
WRN UNITED STATES...WITH 12 HOUR HEIGHT FALLS OF UP TO 90 METERS
AT KOAK IN CA. A JET MAX OF AROUND 110 KTS WAS STILL OUT OVER THE
PACIFIC AT 300 MB...ON THE BACKSIDE OF THE TROUGH. LATEST WATER
VAPOR AND IR STLT IMAGERY SHOWED JUST SOME CIRRUS LOCALLY...WITH
AREAS OF FOG TO THE EAST IN IA AND THICKER MID LEVEL CLOUDS OVER
THE ROCKIES. AT THE SFC...A RIDGE WAS TO OUR EAST AND A TROUGH TO
THE WEST...FROM ERN MT INTO ERN CO. S OR SE WINDS WERE NOTED WITH
DEWPOINTS IN THE 40S. THE KOAX SOUNDING FROM LAST EVENING ONLY HAD
ABOUT 0.33 PW. THERE WAS SOME BETTER MOISTURE TO OUR S.
TODAY...WILL PROBABLY KEEP THE FCST DRY. THE 00Z NAM AND EVEN SOME
RECENT RAP MODEL RUNS TRIED TO DVLP ISOLD LGT PCPN OVER PARTS OF
THE AREA THIS MORNING. 06Z NAM AND MOST OF THE RECENT EXPERIMENTAL
HRRR RUNS DID NOT SHOW ANY PCPN. AS THE PRES GRADIENT TIGHTENS
TODAY...IT WILL BECOME BREEZY OR WINDY. PREVIOUS FCST HIGHS LOOKED
PRETTY GOOD...MAINLY 75 TO 80...SO CHANGES WERE MINOR.
PCPN CHANCES WILL BE INCREASING TONIGHT. GENLY FELT THAT MUCH OF
THE EVENING WOULD BE DRY...DESPITE SOME PCPN SHOWN BY THE GFS.
OTHER MODELS KEEP BEST PCPN CHANCES W OF OUR AREA UNTIL AFTER
MIDNIGHT. POPS MAINLY FROM 20-30 PCT SEEM PRUDENT BASED ON THE
MOISTURE RETURN AND FORCING. TREND SHOULD BE FOR PCPN TO TRY TO
DIE OUT SUN MORNING...THEN REDEVELOP IN THE AFTN. THERE IS FAIRLY
GOOD MODEL AGREEMENT ON THAT. SPC DAY 2 OTLK SHOWS SLGT CHANCE OF
SVR AND BASED ON INSTABILITY AND SHEAR FCSTS...THAT LOOKS RIGHT.
BOUNDARY LAYER CAPE VALUES UP TO ABOUT 1500 J/KG SEEM PSBL. THE
HIGHEST TSTM CHANCES WILL BE ACRS ABOUT THE SERN 1/2 OF THE FCST
AREA. LOOK FOR LOWS TNGT 55 TO 60 AND HIGHS SUN MOSTLY MID OR
UPPER 70S.
A FRONT WILL MOVE DOWN THROUGH THE AREA MON...BUT LIFT LOOKS WEAK
SO HAVE KEPT POPS BELOW 15 PCT FOR NOW.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 320 AM CDT SAT APR 23 2016
WEAK HIGH PRES SHOULD BE OVER THE AREA MON NGT...WITH CONTINUED
DRY WEATHER. BUT...A CLOSED LOW WILL BE ORGANIZING TO OUR W/SW
MOST LIKELY OVER UT OR NRN AZ. THAT SHOULD MOVE OUT TO WRN KS BY
12Z WED...THEN PROBABLY INTO IA BY 12Z THU. YET ANOTHER CLOSED LOW
IS EXPECTED TO BE OVER SRN CA BY THU MORNING. MODEL AGREEMENT IS
NOT OVERLY GREAT BY FRI...BUT THE GENERAL CONSENSUS IS THAT THE
LOW WILL PROBABLY OPEN UP AND MOVE OUT INTO THE HIGH PLAINS BY THE
WEEKEND.
THE 00Z GFS WAS SLOWER BRINGING A CHANCE OF SHRA/TSTMS BACK TO THE
AREA ON TUE COMPARED TO THE ECMWF. GAVE BOTH MODELS EQUAL WEIGHT
FOR NOW. PCPN SHOULD BE FAIRLY WIDESPREAD TUE NGT/WED...WHICH MAY
HELP LIMIT STRONG STORM COVERAGE. CURRENT EXPECTED TIMING DRIES
THE AREA OUT FOR THE PD FROM THU INTO FRI MORNING...THEN PCPN IS
LIKELY TO RETURN.
&&
.AVIATION...(06Z TAFS FOR KOMA...KLNK...KOFK THROUGH 06Z SUNDAY)
ISSUED AT 1136 PM CDT FRI APR 22 2016
SOME MVFR CLOUDS ARE DEVELOPING ABOUT 40 MILES EAST OF KOMA. DON`T
BELIEVE THEY WILL DEVELOP WESTWARD INTO OMAHA. A COUPLE OF MODELS
ALSO DEVELOP SOME MVFR FOG AT KOMA LATER TONIGHT AS WELL.
OTHERWISE...VFR CONDITIONS...WITH SOUTHEAST WINDS INCREASING TO 19
TO 32 KNOTS BY 14-17Z.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
220 AM PDT SAT APR 23 2016
.SYNOPSIS...AS ONE SYSTEM MOVES OUT OF THE REGION TODAY ANOTHER
SYSTEM WILL MOVE INTO THE WEST COAST SUNDAY AND MONDAY. THIS WILL
BRING ANOTHER ROUND OF GUSTY WINDS ALONG WITH A CHANCE OF SHOWERS TO
MUCH OF THE REGION. TEMPERATURES LOOK TO REMAIN BELOW NORMAL THROUGH
MUCH OF NEXT WEEK.
&&
.SHORT TERM...THROUGH MONDAY NIGHT.
WINDS HAVE BEEN ON THE DECREASE OVER MUCH OF THE REGION EARLY THIS
MORNING...BUT THERE ARE STILL A FEW DOWNSLOPE PRONE AREAS WEST OF
THE SPRING MOUNTAINS THAT ARE SEEING GUSTS INTO ADVISORY LEVELS.
HIRES MODELS DO INDICATE A RAPID DECREASE IN THE STRONGER WINDS
AFTER 10Z SO THE WIND ADVISORY SHOULD EXPIRE ON TIME. THE UPPER LOW
RESPONSIBLE FOR THE WIND AND PRECIPITATION WILL MOVE NORTHEAST TODAY
AND IS EXPECTED TO BE OVER NORTHERN UTAH BY MID DAY TODAY. THERE
STILL LOOKS TO BE SOME RESIDUAL SHOWERS ACROSS NORTHERN LINCOLN
COUNTY...BUT ANYTHING THAT DOES FALL IS EXPECTED TO REMAIN LIGHT AND
SHOULD BE OUT OF THE AREA BY LATE THIS AFTERNOON.
SHORT LIVED AND WEAK HIGH PRESSURE WILL MOVE OVER THE REGION LATE
THIS AFTERNOON INTO EARLY SUNDAY BEFORE THE EFFECTS OF THE NEXT
TROUGH MOVES INTO THE WEST COAST. WE WILL START TO SEE INCREASING
SOUTHWEST WINDS AGAIN SUNDAY AFTERNOON...BUT AT THIS TIME WIND
SPEEDS LOOK TO REMAIN BELOW ADVISORY LEVELS. PRECIPITATION WILL
SPREAD INTO THE SIERRA AND THEN ACROSS THE NORTHERN ZONES SUNDAY
NIGHT. THE BIGGER CHANGES WILL OCCUR MONDAY AS THE MODELS INDICATE A
COLD CLOSED LOW DROPPING SOUTH THROUGH NORTHERN CALIFORNIA AND
WESTERN NEVADA. THIS IS EXPECTED TO BRING MUCH COOLER TEMPERATURES
TO THE REGION ALONG WITH A BETTER CHANCE OF PRECIPITATION TO MUCH OF
THE AREA. THIS SYSTEM DOES NOT HAVE A SIGNIFICANT MOISTURE TAP SO
MAJORITY OF THE PRECIPITATION WILL REMAIN LIGHT...WITH THE EXCEPTION
OF CENTRAL NYE AND LINCOLN COUNTY WHERE MORE WIDESPREAD
PRECIPITATION COULD OCCUR. SNOW LEVELS ARE EXPECTED BE BETWEEN 5000-
6000 FEET...BUT AT THIS TIME SNOW AMOUNTS SHOULD NOT EXCEED ADVISORY
LEVELS. TEMPERATURES WILL DROP ABOUT 10 DEGREES FROM SUNDAYS HIGHS
AND BE AROUND 10 DEGREES BELOW NORMAL. DEPENDING ON WHERE THE UPPER
LOW SETS UP WE COULD SEE A BAND OF STRONGER WINDS ACROSS SAN
BERNARDINO AND SOUTHERN MOHAVE COUNTIES MONDAY AFTERNOON WITH
ADVISORY LEVEL WINDS POSSIBLE.
.LONG TERM...TUESDAY THROUGH FRIDAY.
NOT TOO MUCH CHANGE OVERALL IN THE MODEL SOLUTIONS THIS MORNING AS
COMPARED TO YESTERDAY...WITH ONLY A COUPLE OF TIMING DIFFERENCES.
ACTIVE PATTERN PERSISTS WITH MULTIPLE STORM SYSTEMS PASSING THROUGH
DURING THE PERIOD. PICKING UP TUESDAY MORNING...LOW PRESSURE WHICH
PASSED THROUGH ON MONDAY SHOULD BE MOVING AWAY TO THE EAST. ONE
TIMING DIFFERENCE IS THAT THE MODELS /ESPECIALLY THE GFS/ ARE A BIT
SLOWER WITH THIS SYSTEM THAN YESTERDAY...SUGGESTING THAT PRECIP
CHANCES MAY LINGER INTO TUESDAY OVER LINCOLN COUNTY. TEMPERATURES
WILL BE ABOUT TEN DEGREES BELOW NORMAL TUESDAY IN THE WAKE OF THE
STORM. THE NEXT STORM WILL BE NEAR THE CALIFORNIA COAST BY WEDNESDAY
AFTERNOON...WITH CLOUDS INCREASING AGAIN AREAWIDE AND PRECIP CHANCES
BEGINNING IN THE SIERRA AND SOUTHERN GREAT BASIN. TEMPERATURES WILL
COME UP A FEW DEGREES FROM TUESDAY IN THE SOUTHERN GREAT BASIN AND
SEVERAL DEGREES IN THE MOJAVE DESERT...BUT REMAIN BELOW NORMAL
PRETTY MUCH AREAWIDE. AS THIS STORM ROLLS INTO THE MOJAVE DESERT
THURSDAY...PRECIP CHANCES WILL INCREASE AREAWIDE AND TEMPERATURES
WILL COME BACK DOWN A FEW DEGREES. ANOTHER TIMING DIFFERENCE FROM
YESTERDAY IS THAT THE MODELS ARE SLOWER TO EJECT THIS SYSTEM TO THE
EAST...SUGGESTING THAT PRECIP CHANCES COULD LINGER INTO FRIDAY.
TEMPERATURES MAY ALSO BE SLOW TO RECOVER ON FRIDAY IF THE STORM
HANGS AROUND. ALL IN ALL...AN ACTIVE WEEK AHEAD WITH TEMPERATURES
SOLIDLY BELOW NORMAL FOR MUCH OF THE PERIOD.
&&
.AVIATION...FOR MCCARRAN...WINDS ARE EXPECTED TO SHIFT TO THE
NORTHWEST THIS MORNING WITH SPEEDS GENERALLY BETWEEN 10-15KTS THERE
COULD STILL BE A GUST OR TWO TO AROUND 20KTS...BUT THE MORE
FAVORABLE TIMEFRAME FOR GUSTS WOULD BE IN THE MORNING. WINDS ARE
FORECAST TO SHIFT BACK TO THE SOUTHWEST AFTERNOON SUNSET THIS
EVENING WITH SPEEDS AROUND 6-8KTS. FEW-SCT MID AND HIGH CLOUDS
EXPECTED THROUGH THE PERIOD.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...COLD FRONT WILL MOVE THROUGH THE REGION EARLY THIS
MORNING WITH WINDS GRADUALLY SHIFTING TO THE NORTHWEST AFTER 12Z FOR
AREAS SOUTH OF A DAG-IFP-IGM LINE. WINDS BEHIND THE FRONT ARE
FORECAST TO BECOME NORTHWEST WITH SPEEDS BETWEEN 10-15KTS. SOME
GUSTS UP TO 20KTS ARE POSSIBLE THIS MORNING AND ESPECIALLY DOWN THE
COLORADO RIVER THROUGH THE DAY. ISOLD-SCT RAIN/SNOW SHOWERS ACROSS
NORTHERN LINCOLN COUNTY THROUGH THIS AFTERNOON.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTERS SHOULD REPORT ANY
SIGNIFICANT WEATHER ACCORDING TO STANDARD OPERATING PROCEDURES.
$$
SHORT TERM/AVIATION...GORELOW
LONG TERM.... MORGAN
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
Area Forecast Discussion...UPDATED
National Weather Service Reno NV
1022 PM PDT FRI APR 22 2016
.UPDATE...
Latest radar trends show a rapid decrease in both intensity and
coverage of snow showers as instability/convection decrease across
the interior valleys of northern CA. The upper level shortwave
will exit late tonight with drier and more stable airmass to bring
an end to showers Saturday. Temperatures will remain below
freezing overnight where snow fell today. Therefore roads will see
little improvement until treated. The snow advisory will expire at
11 pm. However, anyone planning travel during the overnight hours
should check the latest road conditions.
&&
.SYNOPSIS...
A break in the wet weather is expected Saturday before more
showers arrive Sunday into Monday. Unsettled weather will continue
through next week with below average temperatures.
&&
.PREVIOUS DISCUSSION... /Issued 736 PM PDT FRI APR 22 2016/
UPDATE...
The cold front has moved completely through western NV as of early
this evening and gradients have relaxed enough to go ahead and
drop the wind advisories and areas of blowing dust. Winds will
still be locally gusty before subsiding further this evening, but
well below earlier peaks.
Convection continues to fire over the Sacramento Valley and then
move eastward into the Tahoe Basin. Moderate to heavy snow was
falling under some of the stronger showers with roads likely to
remain a mess this evening, especially with the sun setting.
Expect another 1 to 3 inches, locally up to 4 inches this evening
before showers begin to diminish. We will continue the snow
advisory through expiration. Scattered snow showers may also
produce periods of slick roads along Hwy 395 through Mono County.
Make sure to check road conditions if you must travel tonight.
Hohmann
SYNOPSIS...
Moderate to occasionally heavy bands of snow showers will continue
across the Tahoe Basin through this evening with showers more
scattered elsewhere tonight. A break is expected Saturday before
more showers arrive Sunday into Monday. Unsettled weather will
continue through next week with below average temperatures.
PREVIOUS DISCUSSION... /Issued 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...None.
CA...None.
&&
$$
For more information from the National Weather Service visit...
http://weather.gov/reno
AREA FORECAST DISCUSSION.
HIGHS TODAY WILL BE MAINLY 50S IN CENTRAL NEW YORK...AND IN THE
UPPER 50S-LOWER 60S ALONG AND ESPECIALLY SOUTH OF THE TWIN TIERS.
LOWER ELEVATIONS OF PIKE-SULLIVAN COUNTIES MAY EVEN GET INTO THE
MIDDLE 60S.
HIGH PRESSURE MOVES OVERHEAD TONIGHT...DECOUPLING WIND AND SETTING
UP GOOD RADIATIONAL COOLING CONDITIONS. LOWS WILL REACH TO AROUND
FREEZING PLUS OR MINUS A FEW DEGREES.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
345 AM UPDATE...
HIGH PRESSURE LARGE-AND-IN-CHARGE SUNDAY...THEN A WEST-TO-EAST FRONTAL
ZONE WILL SET UP OVER THE REGION WITH INCREASING CHANCES OF
SHOWERS.
FULL SUNSHINE IS EXPECTED SUNDAY...WITH VERY LIGHT WINDS YET ALSO
EVEN LOWER RELATIVE HUMIDITY VALUES. ONCE AGAIN...DEWPOINTS
NEEDED TO BE LOWERED VERSUS MODEL GUIDANCE...WITH THE VERY DRY
AIR ABOVE THE BOUNDARY LAYER WHICH WILL MIX DOWN DURING PEAK
HEATING. TEMPERATURES WILL MODERATE TO RIGHT AROUND CLIMATOLOGY
FOR HIGHS...UPPER 50S TO MID 60S.
HIGH PRESSURE WILL THEN SHIFT INTO THE ATLANTIC...MAKING ROOM FOR
THE DEVELOPMENT OF A WEST-TO-EAST FRONTAL ZONE OVER THE
REGION...UNDER BRISK ZONAL FLOW ALOFT. MOISTURE WILL AT FIRST
FOCUS NORTH OF THE AREA BUT WITH TIME WILL SAG SOUTHWARD TO
INCLUDE OUR REGION. INITIAL CHANCES OF SHOWERS WILL BE FAIRLY LOW
LATE SUNDAY NIGHT-MONDAY MORNING...AND MAINLY IN CENTRAL NEW YORK.
THEN ONE OR POSSIBLY TWO WAVES OF LOW PRESSURE AND ASSOCIATED
SHORTWAVES...WILL MOVE THROUGH THE FRONTAL ZONE MONDAY AFTERNOON
THROUGH ESPECIALLY MONDAY NIGHT-TUESDAY...LEADING TO A BETTER
LIKELIHOOD OF SHOWERS DURING THAT TIME. RAIN AMOUNTS DO NOT LOOK
OVERWHELMING...BUT SHOULD PROBABLY ENOUGH TO BE CONSIDERED A
WETTING RAIN FOR FIRE WEATHER CONCERNS...WHICH WOULD BE WELCOME.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
LONG TERM FORECAST CONCERNS NEXT WEEK ARE CENTERED AROUND THE
PASSAGE OF A SLOW MOVING COLD FRONT MONDAY AND TUESDAY WITH RAIN
SHOWERS. THERE IS ANOTHER WEAK COLD FRONT EXPECTED TO PUSH
THROUGH ON THURSDAY AND FRIDAY WITH MORE RAIN. IN BETWEEN THESE
TWO SYSTEMS DURING THE MIDDLE OF THE WEEK AN AREA OF HIGH PRESSURE
WILL BRING A BRIEF RESPITE TO THE REGION WITH DRY WEATHER AND
SLIGHTLY WARMER TEMPERATURES.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
NORTHERLY FLOW WILL CONTINUE TO PREVAIL ACROSS THE REGION TODAY.
THIS FLOW WILL BRING VERY DRY AIR TO THE REGION AND WILL CONTINUE
TO ERODE WHAT REMAINS OF THE DENSE STRATUS DECK FROM THIS
MORNING. THIS DECK SHOULD ERODE QUICKLY OVER THE NEXT HOUR AND ALL
TAF SITES SHOULD LIFT TO VFR. ONCE THE DECK LIFTS... FLIGHT
CONDITIONS WILL REMAIN IN VFR THROUGH THE REMAINDER OF THE
PERIOD.
WINDS THROUGH THE AFTERNOON WILL REMAIN N/NW AROUND 12 KNOTS AS
HIGH PRESSURE SLOWLY MOVES INTO THE REGION. WINDS WILL WEAKEN
SLIGHTLY OVERNIGHT AS HIGH PRESSURE STARTS TO SETTLE.
.OUTLOOK...
SUN OVERNIGHT TO TUE...OCCASIONAL SHOWERS. CHANCE FLIGHT RESTRICTIONS.
WED...BECOMING VFR.
THURS...RESTRICTIONS POSSIBLE WITH RAIN SHOWERS.
&&
.FIRE WEATHER...
A FRONT JUST WENT THROUGH THE REGION BUT ONLY PRODUCED A WETTING
RAIN FOR SOME AREAS. BEHIND THE FRONT...NORTH-NORTHWEST WINDS WILL
PICK UP TO 10-15 MPH WITH GUSTS AROUND 25 MPH AT TIMES. MUCH DRIER
AIR WILL ALSO MOVE INTO THE REGION...ALLOWING RELATIVE HUMIDITY TO
PLUMMET INTO THE 25 TO 35 PERCENT RANGE LATE THIS AFTERNOON. FOR
LOCATIONS THAT DID NOT GET A WETTING RAIN...THIS MAY CONTRIBUTE TO
FIRE ACTIVITY. LOOKING AHEAD...WINDS WILL BE MUCH LIGHTER
SUNDAY...BUT HUMIDITY LEVELS ARE LIKELY TO BE EVEN LOWER. OUR NEXT
GOOD CHANCE FOR A WETTING RAIN WILL BE LATE MONDAY INTO TUESDAY.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN/MDP
NEAR TERM...DJN
SHORT TERM...MDP
LONG TERM...BJT
AVIATION...KAH
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS RALEIGH NC
309 AM EDT SAT APR 23 2016
.SYNOPSIS...A WEAK COLD FRONT WILL EXIT CENTRAL NC THIS
MORNING. A SECONDARY COLD FRONT WILL DROP SOUTHEAST THROUGH THE AREA
THIS EVENING...FOLLOWED BY HIGH PRESSURE WHICH WILL BUILD
INTO THE REGION SUNDAY THROUGH MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 950 PM FRIDAY...
THE UPPER TROUGH AXIS AND SYNOPTIC COLD FRONT REMAIN JUST WEST OF
THE MOUNTAINS THIS EVENING...WHILE THE DOWNSTREAM CLUSTERS OF
SHOWERS AND ISOLATED STORMS HAVE BECOME MOSTLY CONFINED TO ONE
COMMON CONVERGENCE AXIS IN THE COASTAL PLAIN...EAST OF THE RAH CWA.
MOISTURE TRANSPORT REMAINS GREATEST OVER EASTERN NC...WATER VAPOR
IMAGERY STILL SUGGESTS A COUPLE DISTURBANCES ALOFT THAT WILL TRACK
NORTHEAST ACROSS NC THIS EVENING. THE MORE NOTABLE DISTURBANCES
IS CURRENTLY MOVING OVER EAST-CENTRAL SC AND WILL LIKELY CAUSE
SHOWERS TO EXPAND A LITTLE BACK TO THE WEST TOWARD THE I-95 CORRIDOR
AS THEY MOVE THROUGH THE NC COASTAL PLAIN IN THE NEXT FEW HOURS.
LATEST HRRR ITERATIONS SHOW THIS AS THE LAST REAL GASP OF
PRECIP...WITH JUST A FEW ISOLATED SHOWERS NEAR THE COLD FRONT AS IT
MOVES INTO THE MORE STABLE AIRMASS OVER THE PIEDMONT LATER TONIGHT.
AM ISOLATED STORM NEAR OR EAST OF I-95 IS STILL POSSIBLE...BUT THE
THREAT OF STRONG UPDRAFTS AND ANY NEAR SEVERE STORMS HAS LIKELY
PASSED.
THE OTHER FORECAST CONCERN OVERNIGHT IS THE POTENTIAL FOR FOG GIVEN
CLEARING ALOFT FROM WEST TO EAST AND THE DELAYED ARRIVAL OF THE COLD
FRONT AND DRIER NORTHWEST FLOW. WHILE THE SIGNAL IS NOT
OVERWHELMINGLY STRONG...RAP AND HRRR SOUNDINGS INDICATE THE FOG
POTENTIAL PRIMARILY IN THE WESTERN PIEDMONT FROM 05Z TO 10Z. TEMPS
SHOULDN`T HAVE MUCH CHANCE TO FALL PRIOR TOT HE COLD FRONT...WITH
LOWS IN THE MID 50S TO LOWER 60S.
&&
.SHORT TERM /SATURDAY AND SUNDAY NIGHT/...
AS OF 235 PM FRIDAY...
THE INITIAL COLD FRONT SHOULD HAVE MOVED TO COASTAL NC BY DAYBREAK
SAT. AREAS OF LOW CLOUDS AND PATCHY FOG IN THE MORNING SHOULD BURN
OFF QUICKLY WITH DRY AIR ABOVE IT THROUGH THE MID LEVELS. THE MID
LEVEL SHORTWAVE TROUGH AXIS WILL BE SITUATED OVERHEAD THROUGH
CENTRAL VA AND CENTRAL NC AND WILL MOVE SLOWLY ESE THROUGH THE
DAY... BRINGING A POCKET OF HIGHER MID LEVEL LAPSE RATES (AOA 6.0
C/KM) ACROSS THE AREA... REACHING THE ERN FORECAST AREA DURING PEAK
HEATING. WHILE ANY MOISTURE WILL BE SHALLOW... THE POSSIBILITY OF
MINOR INSTABILITY WITH THE ATTENDANT DPVA AND POCKET OF COOLER AIR
ALOFT COULD STILL SUPPORT ISOLATED TO SCATTERED SHOWERS... MAINLY
FROM THE TRIANGLE NORTH AND EAST IN THE AFTERNOON. ANY ADDITIONAL
RAINFALL AMOUNTS WILL BE SMALL. OTHERWISE... EXPECT PARTLY TO MOSTLY
SUNNY SKIES. THIS INITIAL FRONT WILL NOT HAVE A LOT OF COOL AIR
RIGHT BEHIND IT... AS THICKNESSES DROP ONLY SLIGHTLY AND REMAIN
ABOVE NORMAL. EXPECT HIGHS IN THE MID 70S TO NEAR 80. THE SECONDARY
AND MORE SUBSTANTIAL COLD FRONT DROPS SE THROUGH THE AREA SAT
EVENING... WITH SURFACE WINDS SHIFTING FROM NNW TO NE AND A COOLER
RIDGE BUILDING IN FROM THE NORTH. SHOULD SEE MOSTLY CLEAR SKIES SAT
NIGHT... ALTHOUGH SCATTERED STRATOCU ARE POSSIBLE NEAR 4-6 KFT AGL
AS THE 850 MB ANTICYCLONE MOVES IN FROM THE WEST YIELDING A POOLING
OF MOISTURE AT THAT LEVEL OVERNIGHT. THICKNESS DROP BACK DOWN NEAR
OR JUST BELOW NORMAL WITH THE FRONTAL PASSAGE... SUPPORTING LOWS IN
THE LOWER TO MID 50S. -GIH
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 305 AM SATURDAY...
MONDAY THROUGH TUESDAY: MID LEVEL S/W RIDGING TO START THE PERIOD
WILL DAMPEN AS A MID LEVEL S/W TRACKS FROM THE GREAT LAKES TO THE
NORTHEAST U.S. EARLY NEXT WEEK... HELPING TO SEND A BACK DOOR COLD
FRONT TOWARDS THE AREA. THE FRONT WILL REMAIN NORTH OF CENTRAL NC
THROUGH TUESDAY. THUS... EXPECT DRY CONDITIONS OUTSIDE OF A VERY
SMALL CHANCE FOR SOME SHOWERS AND STORMS LATE IN THE DAY ON TUESDAY
ACROSS THE FAR NORTH NEAR THE VA/NC BORDER. WITH SURFACE HIGH
LOCATED OFFSHORE THIS SHOULD ALLOW FOR A WARMING SOUTHWESTERLY
RETURN FLOW... YIELDING HIGHS IN THE LOWER 80S MONDAY TO THE MID TO
UPPER 80S ON TUESDAY. LOWS TEMPS TUESDAY MORNING ARE EXPECTED TO BE
AROUND 60.
TUESDAY NIGHT THROUGH FRIDAY: MEDIUM RANGE MODELS CONTINUE TO
STRUGGLE WITH HOW FAR SOUTH THE AFOREMENTIONED BACKDOOR COLD FRONT
MAKES IT. HOWEVER... THE TREND HAS BEEN TO PUSH THE FRONT FURTHER
SOUTHWARD AND INTO CENTRAL NC BY TUESDAY NIGHT INTO WEDNESDAY...
WITH THE GFS NOW PUSHING THE FRONT WELL TO THE SOUTH OF THE AREA.
THUS... WEDNESDAY HIGH TEMPS FORECAST HAS A HIGH BUST POTENTIAL. THE
RAW GFS TEMPS HAVE HIGHS IN THE UPPER 50S TO MID 60S ON WEDNESDAY...
WHILE THE ECMWF IS CLOSER TO WPC VALUES... HIGHS RANGING FROM THE
MID 70S NE TO THE MID TO UPPER 80S SW. FOR NOW WILL STICK CLOSE TO
WPC AND SHOW THE FRONT STALLING ACROSS THE AREA ON WEDNESDAY... WITH
THE POTENTIAL FOR SOME SHOWERS AND STORMS (SLIGHT CHANCE TO LOW END
CHANCE).
CONFIDENCE DECREASES FURTHER THURSDAY INTO FRIDAY. AS THE NEXT IN A
PARADE OF S/W DISTURBANCE TRACKS FROM THE WESTERN U.S... STARTING
OUT AS A DEEP MID/UPPER LEVEL LOW/TROUGH.... THEN OPENING/WEAKENING
SOME AS IT SHIFTS EASTWARD. HOWEVER... TIMING OF THIS NEXT
DISTURBANCE AND EVENTUAL TRACK ARE IN GREAT QUESTION AT THIS TIME.
GIVEN WE ARE TALKING ABOUT A SYSTEM THAT IS YET TO BREAK OFF FROM A
DEEP VORTEX NEAR/SOUTH OF ALASKA... WILL KEEP POPS LOW AND TREND THE
TIMING OF THE ASSOCIATED FRONT TOWARDS WPC (LATE WEEK/FRIDAY). TEMPS
WILL BE TRICKY AND LARGELY DRIVEN BY HOW QUICKLY THE PREVIOUS FRONT
DISSIPATES/RETREATS NORTHWARD. FOR NOW WILL GO WITH HIGHS IN THE
LOWER TO MID 80S LATE NEXT WEEK... WITH LOWS GENERALLY IN THE UPPER
50S TO LOWER 60S.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 835 PM FRIDAY...
AREAS OF LIGHT TO BRIEFLY MODERATE RAIN WILL EXIT THE COASTAL PLAIN
COUNTIES PRIOR TO DAYBREAK AS A SFC COLD FRONT CROSSES CENTRAL NC.
IN THE WAKE OF THE RAIN...CEILINGS AND VISIBILITIES WILL LOWER INTO
THE IFR/LIFR CATEGORY. THE VERY POOR AVIATION CONDITIONS EXPECTED
PRIMARILY BETWEEN 09Z-13Z/ AFTER 13Z...CEILINGS AND VISIBILITIES
WILL QUICKLY IMPROVE...LEADING TO VFR CONDITIONS AREAWIDE BY 15Z.
A STEADY NLY WIND AROUND 10KTS WILL DEVELOP AROUND 14Z AND PERSIST
WELL INTO THE AFTERNOON.
WITH HEATING...EXPECT A BROKEN STRATOCU DECK TO FORM WITH CEILINGS
4000-6000FT ANTICIPATED. A FEW SHOWERS MAY ALSO DEVELOP...MAINLY
BETWEEN 19Z SATURDAY-01Z SUNDAY... AND PRIMARILY TO THE NORTH OF
KRDU AND KRWI. THESE SHOWERS WILL BE ALONG/AHEAD OF A SECONDARY
FRONT THAT WILL CROSS OUR REGION EARLY THIS EVENING.
HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT...LEADING TO A PERIOD
OF VFR CONDITIONS WHICH SHOULD LAST UNTIL TUESDAY. AN APPROACHING
FRONT WILL BRING THE NEXT CHANCE FOR SUB VFR CONDITIONS TO CENTRAL
NC TUESDAY NIGHT INTO WEDNESDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...22
SHORT TERM...HARTFIELD
LONG TERM...BSD
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
132 AM EDT SAT APR 23 2016
.SYNOPSIS...A WEAK COLD FRONT WILL EXIT CENTRAL NC THIS
MORNING. A SECONDARY COLD FRONT WILL DROP SOUTHEAST THROUGH THE AREA
THIS EVENING...FOLLOWED BY HIGH PRESSURE WHICH WILL BUILD
INTO THE REGION SUNDAY THROUGH MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 950 PM FRIDAY...
THE UPPER TROUGH AXIS AND SYNOPTIC COLD FRONT REMAIN JUST WEST OF
THE MOUNTAINS THIS EVENING...WHILE THE DOWNSTREAM CLUSTERS OF
SHOWERS AND ISOLATED STORMS HAVE BECOME MOSTLY CONFINED TO ONE
COMMON CONVERGENCE AXIS IN THE COASTAL PLAIN...EAST OF THE RAH CWA.
MOISTURE TRANSPORT REMAINS GREATEST OVER EASTERN NC...WATER VAPOR
IMAGERY STILL SUGGESTS A COUPLE DISTURBANCES ALOFT THAT WILL TRACK
NORTHEAST ACROSS NC THIS EVENING. THE MORE NOTABLE DISTURBANCES
IS CURRENTLY MOVING OVER EAST-CENTRAL SC AND WILL LIKELY CAUSE
SHOWERS TO EXPAND A LITTLE BACK TO THE WEST TOWARD THE I-95 CORRIDOR
AS THEY MOVE THROUGH THE NC COASTAL PLAIN IN THE NEXT FEW HOURS.
LATEST HRRR ITERATIONS SHOW THIS AS THE LAST REAL GASP OF
PRECIP...WITH JUST A FEW ISOLATED SHOWERS NEAR THE COLD FRONT AS IT
MOVES INTO THE MORE STABLE AIRMASS OVER THE PIEDMONT LATER TONIGHT.
AM ISOLATED STORM NEAR OR EAST OF I-95 IS STILL POSSIBLE...BUT THE
THREAT OF STRONG UPDRAFTS AND ANY NEAR SEVERE STORMS HAS LIKELY
PASSED.
THE OTHER FORECAST CONCERN OVERNIGHT IS THE POTENTIAL FOR FOG GIVEN
CLEARING ALOFT FROM WEST TO EAST AND THE DELAYED ARRIVAL OF THE COLD
FRONT AND DRIER NORTHWEST FLOW. WHILE THE SIGNAL IS NOT
OVERWHELMINGLY STRONG...RAP AND HRRR SOUNDINGS INDICATE THE FOG
POTENTIAL PRIMARILY IN THE WESTERN PIEDMONT FROM 05Z TO 10Z. TEMPS
SHOULDN`T HAVE MUCH CHANCE TO FALL PRIOR TOT HE COLD FRONT...WITH
LOWS IN THE MID 50S TO LOWER 60S.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 235 PM FRIDAY...
THE INITIAL COLD FRONT SHOULD HAVE MOVED TO COASTAL NC BY DAYBREAK
SAT. AREAS OF LOW CLOUDS AND PATCHY FOG IN THE MORNING SHOULD BURN
OFF QUICKLY WITH DRY AIR ABOVE IT THROUGH THE MID LEVELS. THE MID
LEVEL SHORTWAVE TROUGH AXIS WILL BE SITUATED OVERHEAD THROUGH
CENTRAL VA AND CENTRAL NC AND WILL MOVE SLOWLY ESE THROUGH THE
DAY... BRINGING A POCKET OF HIGHER MID LEVEL LAPSE RATES (AOA 6.0
C/KM) ACROSS THE AREA... REACHING THE ERN FORECAST AREA DURING PEAK
HEATING. WHILE ANY MOISTURE WILL BE SHALLOW... THE POSSIBILITY OF
MINOR INSTABILITY WITH THE ATTENDANT DPVA AND POCKET OF COOLER AIR
ALOFT COULD STILL SUPPORT ISOLATED TO SCATTERED SHOWERS... MAINLY
FROM THE TRIANGLE NORTH AND EAST IN THE AFTERNOON. ANY ADDITIONAL
RAINFALL AMOUNTS WILL BE SMALL. OTHERWISE... EXPECT PARTLY TO MOSTLY
SUNNY SKIES. THIS INITIAL FRONT WILL NOT HAVE A LOT OF COOL AIR
RIGHT BEHIND IT... AS THICKNESSES DROP ONLY SLIGHTLY AND REMAIN
ABOVE NORMAL. EXPECT HIGHS IN THE MID 70S TO NEAR 80. THE SECONDARY
AND MORE SUBSTANTIAL COLD FRONT DROPS SE THROUGH THE AREA SAT
EVENING... WITH SURFACE WINDS SHIFTING FROM NNW TO NE AND A COOLER
RIDGE BUILDING IN FROM THE NORTH. SHOULD SEE MOSTLY CLEAR SKIES SAT
NIGHT... ALTHOUGH SCATTERED STRATOCU ARE POSSIBLE NEAR 4-6 KFT AGL
AS THE 850 MB ANTICYCLONE MOVES IN FROM THE WEST YIELDING A POOLING
OF MOISTURE AT THAT LEVEL OVERNIGHT. THICKNESS DROP BACK DOWN NEAR
OR JUST BELOW NORMAL WITH THE FRONTAL PASSAGE... SUPPORTING LOWS IN
THE LOWER TO MID 50S. -GIH
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 305 AM FRIDAY...
SUNDAY THROUGH TUESDAY: HIGH PRESSURE WILL MOVE FROM THE MID-
ATLANTIC STATES TO OFF OF THE CAROLINA COAST ON SUNDAY AND STAY
THERE THROUGH THE EARLY PART OF THE WORK WEEK. THIS WILL PUT CENTRAL
NC IN THE SOUTHWESTERLY RETURN FLOW AND HELP TEMPERATURES RISE INTO
THE MID TO EVEN UPPER 80S BY THE TIME TUESDAY AFTERNOON COMES
AROUND. PRIOR TO THAT...TEMPS ON SUNDAY WILL TOP OUT IN THE MID TO
UPPER 70S BEFORE RISING INTO THE LOW 80S ON MONDAY. LOWS DURING THIS
TIME IN THE MID 50S TO LOWER 60S.
WEDNESDAY THROUGH FRIDAY: A LOW PRESSURE SYSTEM SITUATED OVER THE
CENTRAL U.S. WILL MOVE TOWARDS THE GREAT LAKES ON WEDNESDAY AS A
BACKDOOR COLD FRONT EXTENDING NEARLY DUE EAST FROM THE CENTER OF THE
LOW IS EXPECTED TO MOVE THROUGH THE MID-ATLANTIC STATES AND APPROACH
THE NORTHERN PARTS OF THE FORECAST AREA. THEREFORE THERE WILL BE A
SLIGHT CHANCE OF SHOWERS ESPECIALLY ACROSS THE NORTH ON WEDNESDAY
BUT CONFIDENCE IS STILL LOW ON HOW FAR SOUTH THE FRONT WILL
PROGRESS. WHILE SOME CAPE IS AVAILABLE WEDNESDAY AFTERNOON...THE
SHEAR IS MEAGER UNTIL LATE AFTERNOON WHEN IT PICKS UP ACROSS THE NW
PIEDMONT. THEREFORE A THUNDERSTORM IS POSSIBLE BUT THE MODE OF
PRECIPITATION...IF WE GET ANY...SHOULD BE JUST SHOWERS FOR MUCH OF
THE DAY. THE GFS IS PREDICTING THE COLD FRONT TO MOVE ALL THE WAY
THROUGH NC BECAUSE OF A DEVELOPING MESO-HIGH NORTH OF THE AREA BUT
THIS FEATURE IS LESS PRONOUNCED IN MOST OTHER MODELS. THE ECMWF
FOLLOWS MORE IN LINE WITH WPC THINKING WITH THE COLD FRONT ONLY
REACHING THE NORTHERN PARTS OF THE STATE. MOST MODEL BLENDS ALSO
KEEP US LARGELY IN THE WARM SECTOR ON WEDNESDAY AS WELL. THEREFORE
TRENDING WARMER WITH TEMPERATURES WEDNESDAY AFTERNOON WITH HIGHS AT
LEAST IN THE LOW TO MID 80S WITH SOME UPPER 80S POSSIBLE IN THE
SOUTHWEST. LOWS IN THE UPPER 50S TO LOW 60S WEDNESDAY NIGHT INTO
THURSDAY MORNING.
A SECOND COLD FRONT WILL APPROACH THE AREA AS THE LOW PRESSURE
SYSTEM MOVES NORTHEAST WEDNESDAY NIGHT AND INTO THURSDAY MORNING.
THE COLD FRONT SHOULD MOVE THROUGH THE AREA THROUGHOUT THE DAY ON
THURSDAY BRINGING A CHANCE OF SHOWERS AND A SLIGHT CHANCE OF
THUNDERSTORMS. SHOWERS COULD EXTEND INTO FRIDAY DEPENDING ON THE
POSITION OF THE COLD FRONT AND HOW WELL IT HOLDS TOGETHER BUT
CONFIDENCE IN THE FORECAST THIS FAR OUT IS LOW AT THIS TIME. WILL
CARRY LOW SLIGHT CHANCE POPS IN THE FORECAST FOR NOW. DESPITE THE
SURFACE FRONT TRYING TO MOVE THROUGH THE AREA...THERE WILL NOT BE
MUCH CHANGE IN AIRMASS ON FRIDAY THEREFORE TEMPS ARE EXPECTED TO BE
HIGHER THAN AVERAGE WITH HIGHS IN THE LOW TO MID 80S THURSDAY
AND FRIDAY AND LOWS IN THE UPPER 50S TO MID 60S.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 835 PM FRIDAY...
AREAS OF LIGHT TO BRIEFLY MODERATE RAIN WILL EXIT THE COASTAL PLAIN
COUNTIES PRIOR TO DAYBREAK AS A SFC COLD FRONT CROSSES CENTRAL NC.
IN THE WAKE OF THE RAIN...CEILINGS AND VISIBILITIES WILL LOWER INTO
THE IFR/LIFR CATEGORY. THE VERY POOR AVIATION CONDITIONS EXPECTED
PRIMARILY BETWEEN 09Z-13Z/ AFTER 13Z...CEILINGS AND VISIBILITIES
WILL QUICKLY IMPROVE...LEADING TO VFR CONDITIONS AREAWIDE BY 15Z.
A STEADY NLY WIND AROUND 10KTS WILL DEVELOP AROUND 14Z AND PERSIST
WELL INTO THE AFTERNOON.
WITH HEATING...EXPECT A BROKEN STRATOCU DECK TO FORM WITH CEILINGS
4000-6000FT ANTICIPATED. A FEW SHOWERS MAY ALSO DEVELOP...MAINLY
BETWEEN 19Z SATURDAY-01Z SUNDAY... AND PRIMARILY TO THE NORTH OF
KRDU AND KRWI. THESE SHOWERS WILL BE ALONG/AHEAD OF A SECONDARY
FRONT THAT WILL CROSS OUR REGION EARLY THIS EVENING.
HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT...LEADING TO A PERIOD
OF VFR CONDITIONS WHICH SHOULD LAST UNTIL TUESDAY. AN APPROACHING
FRONT WILL BRING THE NEXT CHANCE FOR SUB VFR CONDITIONS TO CENTRAL
NC TUESDAY NIGHT INTO WEDNESDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...22
SHORT TERM...HARTFIELD
LONG TERM...ELLIS/DND
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
102 AM EDT SAT APR 23 2016
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE AREA LATE TONIGHT. AN UPPER
LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA EARLY ON SATURDAY.
HIGH PRESSURE WILL BUILD ACROSS THE AREA DURING THE
WEEKEND...MOVING OFFSHORE EARLY NEXT WEEK. WARM TEMPERATURES AND
DRY WEATHER ARE EXPECTED THROUGH MIDWEEK...WITH SCATTERED
THUNDERSTORMS POSSIBLE WITH INCREASING HEAT AND HUMIDITY TOWARDS
THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1 AM SATURDAY...BULK OF CONVECTION HAS NOW MOVED NE OF THE
FORECAST AREA...WITH PENDER COUNTY NOW SEEING MOST OF WHAT IS
LEFT. FORECAST IN GOOD SHAPE...NO CHANGES ANTICIPATED WITH THE
LATEST UPDATE. PREVIOUS DISCUSSION FOLLOWS:
THINGS HAVE UNFOLDED PRETTY MUCH AS EXPECTED OVER THE PAST
SEVERAL HOURS..AND THAT`S QUITE UNUSUAL WHERE CONVECTION IS
INVOLVED! SURFACE-BASED INSTABILITY IS NOW LIMITED TO A NARROW
STRIP ALONG THE IMMEDIATE COAST WHERE TEMPERATURES ARE STILL NEAR
70 DEGREES. INLAND CONVECTION HAS LARGELY DECAYED INTO STRATIFORM
RAIN WHICH EXTENDS AS FAR BACK AS DARLINGTON AND MARLBORO COUNTIES
IN SOUTH CAROLINA.
OVER THE PAST FEW HOURS RAINFALL HAS BEEN QUITE SUBSTANTIAL ACROSS
PORTIONS OF THE SC PEE DEE REGION. THE HIGHEST TOTALS ON OUR
MESONET INCLUDE 2.35 INCHES IN NICHOLS (MARION COUNTY), 1.75
INCHES IN KINGSTREE (WILLIAMSBURG COUNTY), AND 1.73 INCHES IN
GREEN SEA (HORRY COUNTY). RADAR ESTIMATES RANGE AS HIGH AS 3.4
INCHES JUST SOUTH OF FLORENCE AND WEST OF MARION. RAINFALL TOTALS FROM
THIS POINT FORWARD SHOULD BE HIGHEST ACROSS THE CAPE FEAR REGION
OF SE NORTH CAROLINA WITH UP TO AN INCH POSSIBLE WHERE TRAINING IS
OCCURRING FROM LAKE WACCAMAW NORTHEASTWARD TO NEAR WALLACE.
LATEST HRRR AND HRRRX RAINFALL PROJECTIONS LOOK VERY REASONABLE.
DISCUSSION FROM 700 PM FOLLOWS...
STRONG THUNDERSTORM ACTIVITY ACROSS THE SOUTH CAROLINA PEE DEE
REGION HAS YET TO BECOME SEVERE. WE RECEIVED A COUPLE OF REPORTS
OF SMALL HAIL (0.5 TO 0.75 INCH DIAMETER) EARLIER FROM THE
FLORENCE VICINITY. BASED ON TEMPERATURES ALOFT WE`RE LOOKING FOR
50 DBZ ECHOES AT OR ABOVE 26000 FEET TO INDICATE A SEVERE HAIL
RISK TODAY. SO FAR REFLECTIVITY CORES ALOFT HAVE REMAINED BELOW
THIS LEVEL. SURFACE- BASED CAPE IS STILL NEAR 1000 J/KG IN THE
WARM AIR (TEMPS > 70) OUT AHEAD OF THE STORMS.
EVOLUTION OF THE CONVECTION OVER THE NEXT FEW HOURS WILL PROBABLY
FOCUS LESS ON SURFACE-BASED INSTABILITY AND MORE ON ELEVATED
INSTABILITY COUPLED WITH SYNOPTICALLY-DRIVEN LOW LEVEL CONVERGENCE
ACROSS THE INTERIOR COASTAL PLAIN. VIRTUALLY ALL MODELS SHOW THE
WEAK AREA OF LOW PRESSURE SOUTH OF ORANGEBURG SC WILL MOVE SLOWLY
NORTH-NORTHEASTWARD. CONVERGING WINDS INTO THIS FEATURE SHOULD
HELP MAINTAIN SHOWERS AND THUNDERSTORMS LARGELY WHERE THE ACTIVITY
CURRENTLY IS OVER THE NEXT SEVERAL HOURS. OUR FOCUS MAY SHIFT
AWAY FROM A HAIL RISK TO A FLOODING RISK WITH TIME.
AS THE WEAK LOW FINALLY MAKES IT UP INTO SE NORTH CAROLINA BY
MIDNIGHT THE BETTER LOW LEVEL CONVERGENCE SHOULD HELP SUPPORT
SHOWERS AND STORMS DOWN AT THE COAST. FORECAST POPS RANGE FROM 100
PERCENT ALONG THE INTERSTATE 95 CORRIDOR TO 60-90 PERCENT ON THE
COAST...INCREASING FROM SOUTH TO NORTH.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/...
AS OF 220 PM FRIDAY...A ROBUST MID-LEVEL SHORTWAVE TROUGH WILL
MOVE ACROSS THE FORECAST AREA DURING SAT. SHOWERS MAY BE LURKING
NEAR THE COAST AND OFFSHORE AT FIRST LIGHT SAT. THEN AS THIS
FEATURE APPROACHES...SOME COOLING ALOFT COUPLED WITH HEATING AT
THE SURFACE WILL STEEPEN LAPSE RATES. THIS SHOULD ALLOW ISOLATED
TO SCATTERED SHOWERS TO DEVELOP. THE BEST LIFT/COLD POOL
ASSOCIATED WITH THIS DISTURBANCE WILL TRACK N OF THE AREA...WITH
OUR FORECAST AREA ON THE SOUTHERN PERIPHERY. THUS...WILL PORTRAY
HIGHEST POPS NE HALF OF THE FORECAST AREA.
THE SHOWERS SHOULD DISSIPATE WITH THE LOSS OF HEATING WHICH WILL BE
COINCIDENT WITH THE TROUGH MOVING OFFSHORE. WE ARE NOT LOOKING FOR
SIGNIFICANT RAINFALL ON SAT...JUST HIT OR MISS SHOWERS WHICH WILL
TEND TO BE FAST PACED AND THUS BRIEF.
DRY WEATHER THROUGHOUT SAT NIGHT THROUGH SUN NIGHT AS HIGH PRESSURE
BUILDS SOUTHWARD ACROSS THE AREA. TEMPS WILL BE JUST ABOUT NORMAL
FOR LATE APRIL.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 220 PM FRIDAY...THE WEEK WILL BEGIN WITH HIGH PRESSURE
SURFACE-ALOFT PUSHING OFF THE EAST COAST. RETURN FLOW AROUND THE
SURFACE HIGH WILL SET UP LATE MONDAY AND PERSIST THROUGH
WEDNESDAY. 12Z GFS IS INDICATING A WEAK SURFACE FRONT MAY SLIP
SOUTH AND BRIEFLY INTO THE SOUTHERN CWA ON WEDNESDAY BEFORE
QUICKLY LIFTING BACK TO THE NORTH. WILL TWEAK THE FORECAST TOWARDS
THIS SOLUTION BY INDICATING A BRIEF SHIFT TO NORTHEAST WINDS
ACROSS THE NORTHWEST HALF OF THE CWA ON WEDNESDAY. A SMALL CHANCE
OF SHOWERS WILL BE ASSOCIATED WITH THIS BOUNDARY. BETTER CHANCES
FOR CONVECTION ARE EXPECTED ON THURSDAY AND FRIDAY...ALONG WITH A
CHANCE OF THUNDER...AS SURFACE-BASED INSTABILITY INCREASES WITH
SURGING TEMPS/DEWPOINTS. MODELS CONTINUE TO INDICATE A COLD
FRONTAL PASSAGE FRIDAY NIGHT.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 06Z...SHOWERS AND ISOLATED THUNDERSTORMS AHEAD OF A WEAK
COLD FRONT HAVE MOVE MOSTLY NE OF THE TERMINALS EARLY THIS MORNING
LEAVING ISOLATED LIGHT SHOWERS IN ITS WAKE. SHOWERS CHANCES WILL
COME TO AN END EARLY THIS MORNING AS THE FRONT SLOWLY MOVES
EAST...PUSHING OFF THE COAST BEFORE DAYBREAK. WINDS WILL BECOME
W-NW BEHIND THE FRONT... BUT A LACK OF COLD ADVECTION OR A TIGHT
GRADIENT WILL KEEP WINDS LIGHT. LOW LEVEL MOISTURE WILL MANIFEST
AS LOW STRATUS ALONG THE COAST WHERE BOUNDARY LAYER WINDS ARE
SLIGHTLY HIGHER...AND FOG AT INLAND TERMINALS WHERE BOUNDARY LAYER
MIXING WILL BE LESS. THERE WILL BE A PERIOD OF TIME EARLY THIS
MORNING WHERE CEILINGS AND/OR VISIBILITIES WILL DROP INTO THE IFR
CATEGORY...POSSIBLY LIFR AT KFLO/KLBT IF SKIES CLEAR ENOUGH. CIGS
SHOULD INCREASE TO MVFR THEN VFR BY MID-MORNING. WINDS WILL BE
W-NW BECOMING N LATER IN THE AFTERNOON. SOME ISOLATED SHOWERS
POSSIBLE NEAR KILM/KCRE...DISSIPATING BY EVENING.
EXTENDED OUTLOOK...VFR
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1 AM SATURDAY...NO CHANGES ARE NEEDED TO THE FORECAST THIS
EVENING. PREVIOUS DISCUSSION FROM 700 PM FOLLOWS:
HIGH PRESSURE OUT NEAR BERMUDA IS DRAGGING AIR FROM THE NORTHERN
CARIBBEAN AND BAHAMAS UP THE COAST AND ACROSS THE CAROLINAS. A
COLD FRONT JUST WEST OF THE APPALACHIANS IS MOVING EASTWARD AND
SHOULD REACH THE COASTAL WATERS AROUND SUNRISE SATURDAY MORNING.
SOUTH WINDS SHOULD AVERAGE 15 KT ACROSS THE SC WATERS AND 15-20 KT
ACROSS THE NC WATERS TONIGHT... DIMINISHING BY ABOUT 5 KNOTS AFTER
3-4 AM AS A WAVE OF LOW PRESSURE ALONG THE FRONT IN SOUTH CAROLINA
MOVES NORTH OF THE AREA. SHOWERS AND THUNDERSTORMS INLAND SHOULD
REACH THE COASTAL WATERS BY LATE THIS EVENING AND THERE MAY BE
GOOD COVERAGE OF RAIN ACROSS THE WATERS AFTER
MIDNIGHT...ESPECIALLY NORTH OF CAPE FEAR.
SEAS ARE CURRENTLY 3-4 FEET AT THE CAPE FEAR NEARSHORE BUOYS AND 5
FEET OUT AT THE FRYING PAN SHOALS BUOY. LOOK FOR THESE WAVE
HEIGHTS TO BUILD BY ABOUT A FOOT OVER THE NEXT SEVERAL HOURS.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 220 PM FRIDAY...A COLD FRONT MAY LINGER NEAR THE OFFSHORE
WATERS...WAITING ON A POTENT SHORTWAVE TROUGH BEFORE PUSHING
FURTHER OFFSHORE DURING SAT. W WINDS TO START THE DAY SAT ARE
EXPECTED TO VEER TO NW....BEFORE SHIFTING TO THE N AND NE AND
INCREASING TO NEAR 20 KT SAT NIGHT. A SMALL CRAFT SHOULD EXERCISE
CAUTION HEADLINE MAY BE REQUIRED SAT NIGHT INTO EARLY SUN MORNING.
AS HIGH PRESSURE TO THE N GROWS CLOSER...WIND SPEEDS WILL DECREASE
TO 10 TO 15 KT DURING SUN AND TO 10 KT OR LESS SUN NIGHT. THE WIND
DIRECTION WILL VEER FROM NE SUN TO E SUN NIGHT.
LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 220 PM FRIDAY...SURFACE HIGH PRESSURE WILL SHIFT OFF THE
COAST EARLY MONDAY AND WILL BE THE MAIN INFLUENCE ON THE MARINE
FORECAST THROUGH WEDNESDAY. WINDS ARE EXPECTED TO BE LIGHT WITH
SOME VARIABILITY EARLY MONDAY UNTIL THE CENTER OF THE HIGH MOVES
AWAY FROM THE COAST. THIS WILL ALLOW SOUTHWEST WINDS TO DEVELOP
OVER THE WATERS...WHICH WILL INCREASE TO A 10-15 KNOT RANGE TUE-
WED. A WEAK COLD FRONT IS EXPECTED TO APPROACH FROM THE NORTH ON
WEDNESDAY AND WILL RESULT IN WINDS BACKING TO THE EAST AND PERHAPS
NORTHEAST BRIEFLY..GENERALLY NORTH OF CAPE FEAR.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...CRM
NEAR TERM...REK/TRA
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...REK/MRR
MARINE...REK/TRA/JDW
AREA FORECAST DISCUSSION
NWS BISMARCK ND
313 PM CDT SAT APR 23 2016
.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 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 313 PM CDT SAT APR 23 2016
VFR CONDITIONS WILL PREVAIL THIS AFTERNOON AND EVENING WITH A FEW
SHOWERS AND ISOLATED STORMS POSSIBLE. BREEZY EAST-NORTHEAST WINDS
WILL STEADILY INCREASE WITH 25 TO 35 KT GUSTS WIDESPREAD TONIGHT
AND SUNDAY. EXPECT CEILINGS TO LOWER TONIGHT WITH WIDESPREAD MVFR
AND IFR CONDITIONS ACROSS WESTERN AND CENTRAL ND LATE TONIGHT AND
SUNDAY TO GO WITH AN INCREASE IN RAIN AND THUNDERSTORM CHANCES.
THAT SAID...WE HAVE ONLY MODEST CONFIDENCE IN TIMING THE ONSET OF
LOWER CEILINGS AND PRECIPITATION AT ANY SPECIFIC TERMINAL.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KS
LONG TERM...KS
AVIATION...CJS
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
756 AM EDT SAT APR 23 2016
.SYNOPSIS...
A COLD FRONT WILL CONTINUE TO PUSH THROUGH THE REGION EARLY THIS
MORNING...EXITING SOUTHEAST PA BY DAWN. HIGH PRESSURE WILL BUILD
INTO THE REGION THIS WEEKEND. ANOTHER COLD FRONT IS LIKELY TO PUSH
ACROSS THE AREA TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MAIN FEATURE IN WATER VAPOR IMAGERY THIS MORNING IS UPPER LOW
TRACKING ACROSS WEST VIRGINIA. UPPER LVL DIFFLUENCE IN ADVANCE OF
THIS FEATURE IS SUPPORTING LINGERING SHOWERS ACROSS SOUTHEAST PA
AS OF 1030Z. AS UPPER LOW TRACKS EAST...EXPECT THE SHOWERS TO
PUSH SE OF THE REGION LATER THIS MORNING. LATEST HRRR AND NCAR
ENSEMBLE SUGGEST THE SHOWERS COULD LAST UNTIL ARND 14Z OVER
LANCASTER CO.
IR IMAGERY AT 10Z SHOWS AN EXTENSIVE STRATUS SHIELD EXTENDING ALL
THE WAY BACK TO LKS ERIE AND ONTARIO. HOWEVER...MDL SOUNDINGS
CONTINUE TO INDICATE CLEARING SKIES BY THIS AFTERNOON...DUE TO
DEEPENING BLYR AND MIXING OF MUCH DRIER AIR ALOFT. SUPERBLEND
TEMPS LOOKING FAIRLY SEASONABLE THIS AFTN...RANGING FROM THE U50S
OVR THE N MTNS...TO THE M-U60S SE COUNTIES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
HIGH PRESSURE WILL BECOME CENTERED OVER THE REGION LATE TONIGHT
WITH CLEAR SKIES...LOW PWATS AND NEARLY CALM AIR. INCLUDED PATCHY
FROST ACROSS THE MTNS NEAR THE I-80 CORRIDOR AND WIDESPREAD SUB-
FREEZING TEMPS 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.
AFTER THE CHILLY START...ABUNDANT SUNSHINE SHOULD PUSH TEMPS WELL
INTO THE 60S BY SUNDAY AFTN. HIGH PRES DIRECTLY OVERHEAD SHOULD
ENSURE VERY LGT WINDS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
A SURGE OF WARMER AIR SHOULD WORK INTO PA MONDAY...AS HIGH DRIFTS
OFF THE COAST AND WARM FRONT LIFTS NORTHWARD THRU THE E GRT LKS.
MSUNNY SKIES AND MDL 8H TEMPS NR 12C SHOULD SUPPORT MAX TEMPS
FROM THE M70S N MTNS...TO THE L80S IN THE SOUTHERN VALLEYS.
ALL MED RANGE GUIDANCE INDICATES A WEAKENING SHORTWAVE TRACKING
THRU THE E GRK LKS WILL PUSH A COLD FRONT AND ASSOC BAND OF
SHOWERS SOUTHWARD ACROSS PA BY TUESDAY. SOME MDL DISAGREEMENT WITH
REGARDS TIMING OF FROPA...WITH SLOWER ECENS/SREF/CANADIAN
SOLUTIONS CURRENTLY FAVORED OVR THE FASTER GEFS. THIS SLOWER
SOLUTION RESULTS IN A GOOD CHC OF SHOWERS LASTING THRU TUESDAY...RATHER
THAN JUST MON NIGHT. CURRENT MDL-BLENDED QPF INDICATES THIS WILL
BE A RELATIVELY LIGHT RAINFALL FOR MOST OF THE AREA WITH AMTS
GENERALLY LESS THAN A HALF INCH.
LATEST ECENS AND NAEFS POINT TOWARD A DRY/SEASONABLE WEDNESDAY...AS
SFC RIDGE BUILDS ACROSS PA. NEXT CHC OF SHOWERY WX ARRIVES
THURSDAY WHEN ECENS/NAEFS BOTH TRACK A SFC LOW JUST SOUTH OF THE
STATE. FAIR WX LIKELY TO RETURN BY FRIDAY...AS LOW DEPARTS THE NE
COAST AND DRIER NW FLOW FOLLOWS ACROSS PA.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
A COLD FRONT WILL EXITING TO THE SOUTHEAST EARLY TODAY. HIGH
PRESSURE WILL BUILD INTO THE REGION THIS WEEKEND.
UPPER LOW TRACKING ACROSS WEST VIRGINIA WILL KEEP SHOWERS IN THE
LOWER SUSQ FOR NEXT COUPLE OF HOURS. OTHERWISE...AN EXTENSIVE
STRATUS SHIELD IS IN PLACE...PRODUCING WIDESPREAD RESTRICTIONS OF
MVFR IN MOST LOCALES TO IFR IN THE WESTERN AND NORTHERN HIGHER
TERRAIN. AS MIXING KICKS IN...IT WILL TAP INTO MUCH DRIER AIR
ALOFT WHICH WILL BRING IMPROVEMENT TO VFR THROUGH 18Z. A NORTH
WIND WILL PICK UP WITH SFC SPEEDS OF 10-20 MPH...BEFORE TAPERING
OFF THIS EVE.
OUTLOOK...
SUN...NO SIG WX EXPECTED.
MON-TUE...PM SHRA DEVELOPING MONDAY AND CONTINUING INTO TUESDAY.
REDUCTIONS POSSIBLE...MAINLY NW PA.
WED...NO SIG WX EXPECTED.
&&
.FIRE WEATHER...
WINDS WILL BECOME A BIT GUSTY THIS AFTN WITH RELATIVE HUMIDITY
FALLING TO NEAR 30 PERCENT BY LATE AFTN. LATEST BUFKIT SOUNDINGS
SUPPORT GUSTS BTWN 15-20KTS LATER TODAY ACROSS EASTERN PA...WITH
CONDS CLOSE TO RED FLAG CRITERIA POSSIBLE FOR A COUPLE OF HOURS
DURING LATE AFTN OR EARLY EVENING. GIVEN THE MARGINAL CONDS AND
THE LGT RAIN THAT FELL OVERNIGHT...HAVE OPTED NOT TO ISSUE EITHER
A FIRE WX WATCH OR RED FLAG WARNING. DAY SHIFT WILL LIKELY NEED TO
CONTACT PA FORESTRY FOR LATEST ASSESSMENT OF FUEL MOISTURE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD
AVIATION...RXR
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
633 AM EDT SAT APR 23 2016
.SYNOPSIS...
A COLD FRONT WILL CONTINUE TO PUSH THROUGH THE REGION EARLY THIS
MORNING...EXITING SOUTHEAST PA BY DAWN. HIGH PRESSURE WILL BUILD
INTO THE REGION THIS WEEKEND. ANOTHER COLD FRONT IS LIKELY TO PUSH
ACROSS THE AREA TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MAIN FEATURE IN WATER VAPOR IMAGERY THIS MORNING IS UPPER LOW
TRACKING ACROSS WEST VIRGINIA. UPPER LVL DIFFLUENCE IN ADVANCE OF
THIS FEATURE IS SUPPORTING LINGERING SHOWERS ACROSS SOUTHEAST PA
AS OF 1030Z. AS UPPER LOW TRACKS EAST...EXPECT THE SHOWERS TO
PUSH SE OF THE REGION LATER THIS MORNING. LATEST HRRR AND NCAR
ENSEMBLE SUGGEST THE SHOWERS COULD LAST UNTIL ARND 14Z OVER
LANCASTER CO.
IR IMAGERY AT 10Z SHOWS AN EXTENSIVE STRATUS SHIELD EXTENDING ALL
THE WAY BACK TO LKS ERIE AND ONTARIO. HOWEVER...MDL SOUNDINGS
CONTINUE TO INDICATE CLEARING SKIES BY THIS AFTERNOON...DUE TO
DEEPENING BLYR AND MIXING OF MUCH DRIER AIR ALOFT. SUPERBLEND
TEMPS LOOKING FAIRLY SEASONABLE THIS AFTN...RANGING FROM THE U50S
OVR THE N MTNS...TO THE M-U60S SE COUNTIES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
HIGH PRESSURE WILL BECOME CENTERED OVER THE REGION LATE TONIGHT
WITH CLEAR SKIES...LOW PWATS AND NEARLY CALM AIR. INCLUDED PATCHY
FROST ACROSS THE MTNS NEAR THE I-80 CORRIDOR AND WIDESPREAD SUB-
FREEZING TEMPS 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.
AFTER THE CHILLY START...ABUNDANT SUNSHINE SHOULD PUSH TEMPS WELL
INTO THE 60S BY SUNDAY AFTN. HIGH PRES DIRECTLY OVERHEAD SHOULD
ENSURE VERY LGT WINDS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
A SURGE OF WARMER AIR SHOULD WORK INTO PA MONDAY...AS HIGH DRIFTS
OFF THE COAST AND WARM FRONT LIFTS NORTHWARD THRU THE E GRT LKS.
MSUNNY SKIES AND MDL 8H TEMPS NR 12C SHOULD SUPPORT MAX TEMPS
FROM THE M70S N MTNS...TO THE L80S IN THE SOUTHERN VALLEYS.
ALL MED RANGE GUIDANCE INDICATES A WEAKENING SHORTWAVE TRACKING
THRU THE E GRK LKS WILL PUSH A COLD FRONT AND ASSOC BAND OF
SHOWERS SOUTHWARD ACROSS PA BY TUESDAY. SOME MDL DISAGREEMENT WITH
REGARDS TIMING OF FROPA...WITH SLOWER ECENS/SREF/CANADIAN
SOLUTIONS CURRENTLY FAVORED OVR THE FASTER GEFS. THIS SLOWER
SOLUTION RESULTS IN A GOOD CHC OF SHOWERS LASTING THRU TUESDAY...RATHER
THAN JUST MON NIGHT. CURRENT MDL-BLENDED QPF INDICATES THIS WILL
BE A RELATIVELY LIGHT RAINFALL FOR MOST OF THE AREA WITH AMTS
GENERALLY LESS THAN A HALF INCH.
LATEST ECENS AND NAEFS POINT TOWARD A DRY/SEASONABLE WEDNESDAY...AS
SFC RIDGE BUILDS ACROSS PA. NEXT CHC OF SHOWERY WX ARRIVES
THURSDAY WHEN ECENS/NAEFS BOTH TRACK A SFC LOW JUST SOUTH OF THE
STATE. FAIR WX LIKELY TO RETURN BY FRIDAY...AS LOW DEPARTS THE NE
COAST AND DRIER NW FLOW FOLLOWS ACROSS PA.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
SHOWERS WILL CONTINUE TO IMPACT PORTIONS OF SOUTHERN PA THROUGH
DAWN IN VICINITY OF SLOW MOVING COLD FRONT.
TO THE NORTH OF THE FRONT...EXTENSIVE STRATUS SHIELD NOTED ACROSS
NORTHERN PA INTO UPSTATE NY...AND CIGS OVER NORTHERN AND WESTERN
SECTIONS OF CWA WILL GRADUALLY FALL TO MVFR AND IFR AS NORTHERLY
FLOW BEGINS TO INCREASE. GENERALLY VFR OVER THE SE...THOUGH A
BRIEF PERIOD OF MVFR POSS AROUND DAWN.
RESTRICTIONS WILL BE IN PLACE OVER NW HALF TO START THE DAY
SAT AS UPPER TROUGH AXIS PASSES THROUGH...BUT CONDITIONS WILL
IMPROVE TO VFR LATE MORNING AS HIGH PRESSURE BUILDS IN FROM THE
NW. A NORTH WIND WILL PICK UP WITH SFC SPEEDS OF 10-20
MPH...BEFORE TAPERING OFF SAT EVE.
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.
WED...NO SIG WX EXPECTED.
&&
.FIRE WEATHER...
WINDS WILL BECOME A BIT GUSTY THIS AFTN WITH RELATIVE HUMIDITY
FALLING TO NEAR 30 PERCENT BY LATE AFTN. LATEST BUFKIT SOUNDINGS
SUPPORT GUSTS BTWN 15-20KTS LATER TODAY ACROSS EASTERN PA...WITH
CONDS CLOSE TO RED FLAG CRITERIA POSSIBLE FOR A COUPLE OF HOURS
DURING LATE AFTN OR EARLY EVENING. GIVEN THE MARGINAL CONDS AND
THE LGT RAIN THAT FELL OVERNIGHT...HAVE OPTED NOT TO ISSUE EITHER
A FIRE WX WATCH OR RED FLAG WARNING. DAY SHIFT WILL LIKELY NEED TO
CONTACT PA FORESTRY FOR LATEST ASSESSMENT OF FUEL MOISTURE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD
AVIATION...RXR
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
532 AM EDT SAT APR 23 2016
.SYNOPSIS...
A COLD FRONT WILL CONTINUE TO PUSH THROUGH THE REGION EARLY THIS
MORNING...EXITING SOUTHEAST PA BY DAWN. HIGH PRESSURE WILL BUILD
INTO THE REGION THIS WEEKEND. ANOTHER COLD FRONT IS LIKELY TO PUSH
ACROSS THE AREA TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MAIN FEATURE IN WATER VAPOR IMAGERY THIS MORNING IS UPPER LOW
TRACKING ACROSS WEST VIRGINIA. UPPER LVL DIFFLUENCE IN ADVANCE OF
THIS FEATURE IS SUPPORTING LINGERING SHOWERS ACROSS SOUTHERN PA AS
OF 09Z. AS UPPER LOW TRACKS EAST...EXPECT THE SHOWERS TO PUSH SE
OF THE REGION LATER THIS MORNING. LATEST HRRR AND NCAR ENSEMBLE
SUGGEST THE SHOWERS COULD LAST UNTIL ARND 14Z OVER LANCASTER CO.
IR IMAGERY AT 09Z SHOWS AN EXTENSIVE STRATUS SHIELD EXTENDING ALL
THE WAY BACK TO LKS ERIE AND ONTARIO. HOWEVER...MDL SOUNDINGS
CONTINUE TO INDICATE CLEARING SKIES BY MIDDAY...DUE TO DEEPENING
BLYR AND MIXING OF MUCH DRIER AIR ALOFT. SUPERBLEND TEMPS LOOKING
FAIRLY SEASONABLE THIS AFTN...RANGING FROM THE U50S OVR THE N
MTNS...TO THE M-U60S SE COUNTIES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
HIGH PRESSURE WILL BECOME CENTERED OVER THE REGION LATE TONIGHT
WITH CLEAR SKIES...LOW PWATS AND NEARLY CALM AIR. INCLUDED PATCHY
FROST ACROSS THE MTNS NEAR THE I-80 CORRIDOR AND WIDESPREAD SUB-
FREEZING TEMPS 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.
AFTER THE CHILLY START...ABUNDANT SUNSHINE SHOULD PUSH TEMPS WELL
INTO THE 60S BY SUNDAY AFTN. HIGH PRES DIRECTLY OVERHEAD SHOULD
ENSURE VERY LGT WINDS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
A SURGE OF WARMER AIR SHOULD WORK INTO PA MONDAY...AS HIGH DRIFTS
OFF THE COAST AND WARM FRONT LIFTS NORTHWARD THRU THE E GRT LKS.
MSUNNY SKIES AND MDL 8H TEMPS NR 12C SHOULD SUPPORT MAX TEMPS
FROM THE M70S N MTNS...TO THE L80S IN THE SOUTHERN VALLEYS.
ALL MED RANGE GUIDANCE INDICATES A WEAKENING SHORTWAVE TRACKING
THRU THE E GRK LKS WILL PUSH A COLD FRONT AND ASSOC BAND OF
SHOWERS SOUTHWARD ACROSS PA BY TUESDAY. SOME MDL DISAGREEMENT WITH
REGARDS TIMING OF FROPA...WITH SLOWER ECENS/SREF/CANADIAN
SOLUTIONS CURRENTLY FAVORED OVR THE FASTER GEFS. THIS SLOWER
SOLUTION RESULTS IN A GOOD CHC OF SHOWERS LASTING THRU TUESDAY...RATHER
THAN JUST MON NIGHT. CURRENT MDL-BLENDED QPF INDICATES THIS WILL
BE A RELATIVELY LIGHT RAINFALL FOR MOST OF THE AREA WITH AMTS
GENERALLY LESS THAN A HALF INCH.
LATEST ECENS AND NAEFS POINT TOWARD A DRY/SEASONABLE WEDNESDAY...AS
SFC RIDGE BUILDS ACROSS PA. NEXT CHC OF SHOWERY WX ARRIVES
THURSDAY WHEN ECENS/NAEFS BOTH TRACK A SFC LOW JUST SOUTH OF THE
STATE. FAIR WX LIKELY TO RETURN BY FRIDAY...AS LOW DEPARTS THE NE
COAST AND DRIER NW FLOW FOLLOWS ACROSS PA.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
SHOWERS WILL CONTINUE TO IMPACT PORTIONS OF SOUTHERN PA THROUGH
DAWN IN VICINITY OF SLOW MOVING COLD FRONT.
TO THE NORTH OF THE FRONT...EXTENSIVE STRATUS SHIELD NOTED ACROSS
NORTHERN PA INTO UPSTATE NY...AND CIGS OVER NORTHERN AND WESTERN
SECTIONS OF CWA WILL GRADUALLY FALL TO MVFR AND IFR AS NORTHERLY
FLOW BEGINS TO INCREASE. GENERALLY VFR OVER THE SE...THOUGH A
BRIEF PERIOD OF MVFR POSS AROUND DAWN.
RESTRICTIONS WILL BE IN PLACE OVER NW HALF TO START THE DAY
SAT AS UPPER TROUGH AXIS PASSES THROUGH...BUT CONDITIONS WILL
IMPROVE TO VFR LATE MORNING AS HIGH PRESSURE BUILDS IN FROM THE
NW. A NORTH WIND WILL PICK UP WITH SFC SPEEDS OF 10-20
MPH...BEFORE TAPERING OFF SAT EVE.
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.
WED...NO SIG WX EXPECTED.
&&
.FIRE WEATHER...
WINDS WILL BECOME A BIT GUSTY THIS AFTN WITH RELATIVE HUMIDITY
FALLING TO NEAR 30 PERCENT BY LATE AFTN. LATEST BUFKIT SOUNDINGS
SUPPORT GUSTS BTWN 15-20KTS LATER TODAY ACROSS EASTERN PA...WITH
CONDS CLOSE TO RED FLAG CRITERIA POSSIBLE FOR A COUPLE OF HOURS
DURING LATE AFTN OR EARLY EVENING. GIVEN THE MARGINAL CONDS AND
THE LGT RAIN THAT FELL OVERNIGHT...HAVE OPTED NOT TO ISSUE EITHER
A FIRE WX WATCH OR RED FLAG WARNING. DAY SHIFT WILL LIKELY NEED TO
CONTACT PA FORESTRY FOR LATEST ASSESSMENT OF FUEL MOISTURE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD
AVIATION...RXR
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
305 AM EDT SAT APR 23 2016
.SYNOPSIS...
A COLD FRONT WILL CONTINUE TO PUSH THROUGH THE REGION EARLY THIS
MORNING...EXITING SOUTHEAST PA BY DAWN. 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 THIS MORNING/...
SHOWERS STILL FALLING ACROSS SOUTHERN PA AT 06Z IN VICINITY OF
SLOW MOVING COLD FRONT. BASED ON LATEST HRRR AND RADAR
TRENDS...WILL MAINTAIN LIKELY POPS ACROSS THE SOUTHERN COUNTIES
THRU DAWN.
TO THE NORTH OF THE FRONT...EXTENSIVE STRATUS SHIELD NOTED ACROSS
NORTHERN PA INTO UPSTATE NY...SO EXPECT GENERALLY OVERCAST SKIES
THRU DAWN. BLEND OF LATEST LAMP/SUPERBLEND GUIDANCE INDICATE LOW
TEMPS SHOULD RANGE FROM THE L40S ACROSS THE NW MTNS...TO THE M50S
ACROSS THE SE COUNTIES.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/...
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 NIGHT 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 /07Z SATURDAY THROUGH WEDNESDAY/...
SHOWERS WILL CONTINUE TO IMPACT PORTIONS OF SOUTHERN PA THROUGH
DAWN IN VICINITY OF SLOW MOVING COLD FRONT.
TO THE NORTH OF THE FRONT...EXTENSIVE STRATUS SHIELD NOTED ACROSS
NORTHERN PA INTO UPSTATE NY...AND CIGS OVER NORTHERN AND WESTERN
SECTIONS OF CWA WILL GRADUALLY FALL TO MVFR AND IFR AS NORTHERLY
FLOW BEGINS TO INCREASE. GENERALLY VFR OVER THE SE...THOUGH A
BRIEF PERIOD OF MVFR POSS AROUND DAWN.
RESTRICTIONS WILL BE IN PLACE OVER NW HALF TO START THE DAY
SAT AS UPPER TROUGH AXIS PASSES THROUGH...BUT CONDITIONS WILL
IMPROVE TO VFR LATE MORNING AS HIGH PRESSURE BUILDS IN FROM THE
NW. A NORTH WIND WILL PICK UP WITH SFC SPEEDS OF 10-20
MPH...BEFORE TAPERING OFF SAT EVE.
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.
WED...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD/LAMBERT
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD/LAMBERT
LONG TERM...FITZGERALD/GARTNER
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
210 AM EDT SAT APR 23 2016
.SYNOPSIS...
A COLD FRONT WILL CONTINUE TO PUSH THROUGH THE REGION EARLY THIS
MORNING...EXITING SOUTHEAST PA BY DAWN. 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 THIS MORNING/...
SHOWERS STILL FALLING ACROSS SOUTHERN PA AT 06Z IN VICINITY OF
SLOW MOVING COLD FRONT. BASED ON LATEST HRRR AND RADAR
TRENDS...WILL MAINTAIN LIKELY POPS ACROSS THE SOUTHERN COUNTIES
THRU DAWN.
TO THE NORTH OF THE FRONT...EXTENSIVE STRATUS SHIELD NOTED ACROSS
NORTHERN PA INTO UPSTATE NY...SO EXPECT GENERALLY OVERCAST SKIES
THRU DAWN. BLEND OF LATEST LAMP/SUPERBLEND GUIDANCE INDICATE LOW
TEMPS SHOULD RANGE FROM THE L40S ACROSS THE NW MTNS...TO THE M50S
ACROSS THE SE COUNTIES.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/...
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 NIGHT 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 /06Z SATURDAY THROUGH WEDNESDAY/...
SHOWERS CONTINUE TO MOVE TO THE EAST. STILL HAVE A SLIGHT CHANCE
FOR THUNDER BUT HAVE LEFT OUT ANY MENTION OF TSTM IN TAFS. THERE
HAS BEEN LIMITED RESTRICTIONS THROUGH THE EVENING. THOUGH IFR IS
POSSIBLE AT AOO THROUGH 06Z...AND AT MDT...JST AND LNS THROUGH 09Z
AS THE SYSTEM PASSES. THE RESTRICTIONS CONTINUE OVER WESTERN AND
CENTRAL MTNS INTO SAT AS UPPER TROUGH PASSES THROUGH. EXPECT
CONDITIONS TO IMPROVE BETWEEN 13Z TO 15Z AS THE WINDS MIX
DOWN...WITH GUSTY WINDS AND VFR CIGS AND VSBYS THROUGH SATURDAY.
STILL A CHANCE FOR LOW BUT VFR CIGS AT JST.
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...FITZGERALD/LAMBERT
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD/LAMBERT
LONG TERM...FITZGERALD/GARTNER
AVIATION...LAMBERT/RXR
AREA FORECAST DISCUSSION...CORRECTED
NWS LUBBOCK TX
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.
&&
$$
51/33
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
341 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. 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.
&&
$$
51/33
AREA FORECAST DISCUSSION
NWS EL PASO TX/SANTA TERESA NM
422 AM MDT SAT APR 23 2016
.SYNOPSIS...
WE WILL SEE A SLIGHT CHANCE FOR RAIN TODAY EAST OF THE RIO
GRANDE...OTHERWISE IT WILL BE MOSTLY SUNNY AND WARM. FOR SUNDAY
THROUGH THURSDAY WE WILL SEE BREEZY TO WINDY AFTERNOON CONDITIONS
WITH HIGH TEMPERATURES RUNNING A FEW DEGREES ABOVE NORMAL UNDER
MOSTLY SUNNY SKIES. FOR FRIDAY AND SATURDAY WE WILL SEE A SLIGHT
CHANCE FOR RAIN IN AREA MOUNTAINS.
&&
.DISCUSSION...
WE DID SEE SOME ISOLATED HEAVY RAIN YESTERDAY WITH A FEW SPOTS
EVEN GETTING SOME SMALL HAIL. MOST OF US THOUGH SAW LOTS OF CLOUDS
BUT LITTLE OR NO RAIN. THE MOISTURE IS QUICKLY MOVING TO THE EAST
OF THE AREA THIS MORNING...BUT THERE WILL BE ENOUGH MOISTURE
LINGERING TO GIVE US A SLIGHT CHANCE FOR AFTERNOON THUNDERSTORMS
EAST OF THE RIO GRANDE. THESE STORMS (IF THERE ARE ANY) WILL BE
VERY SPOTTY IN NATURE. IF A STORM DOES POP UP IT WILL BE CAPABLE
OF PRODUCING SOME STRONG OUTFLOW WINDS. THE VAST MAJORITY OF US
WILL STAY WARM AND DRY TODAY AS A ZONAL FLOW WILL HELP GIVE US
BREEZY AFTERNOON WINDS. SPEAKING OF WINDS THAT WILL BE THE STORY
FOR MUCH OF THE NEXT WEEK. WE WILL SEE BREEZY TO WINDY CONDITIONS
TODAY THROUGH AT LEAST TUESDAY. TUESDAY`S WINDS MAY APPROACH
ADVISORY LEVEL (25 TO 35 MPH) AS AN UPPER LEVEL TROUGH PASSES TO
OUR NORTH. WE WILL LIKELY SEE MORE BREEZY AFTERNOON WINDS TO
FINISH OUT THE WEEK (IT IS STILL THE WINDY SEASON AFTER ALL).
TEMPERATURES FOR MUCH OF THE COMING WEEK WILL BE NEAR OR A FEW
DEGREES ABOVE NORMAL. BY THE END OF NEXT WEEK ANOTHER APPROACHING
UPPER LEVEL STORM SYSTEM WILL BRING A SLIGHT CHANCE FOR RAIN TO
THE GILA REGION.
&&
.AVIATION...VALID 23/12Z-24/12Z
WE WILL SEE VFR CONDITIONS FOR THE NEXT 24 HOURS (AND SEVERAL DAYS
BEYOND THAT). THERE WILL BE JUST ENOUGH MOISTURE TO HELP FUEL A
FEW ISOLATED THUNDERSTORMS EAST OF THE RIO GRANDE THIS AFTERNOON.
IF STORMS DO DEVELOP THEY WILL BE CAPABLE OF PRODUCING SOME STRONG
GUSTY SURFACE WINDS. WE WILL SEE CLOUDS OF MAINLY FEW-SCT080 THIS
AFTERNOON...BUT A FEW SPOTS COULD SEE A CEILING OF BKN080. SURFACE
WINDS WILL BE FROM THE WEST AND GUSTY THIS AFTERNOON 24015G25KT.
&&
.FIRE WEATHER...
WE WILL SEE AN ACTIVE WEEK FOR FIRE WEATHER WITH THE WINDS BEING
THE NEWS MAKER. FOR TODAY AND SUNDAY WE WILL SEE NEAR READ FLAG
CONDITIONS AS WE WILL HAVE GUSTY AFTERNOON WINDS WITH MIN RH`S IN
THE TEENS TODAY AND IN THE UPPER SINGLE DIGITS ON SUNDAY IN THE
LOWLANDS. FOR MONDAY AND TUESDAY WE WILL STILL SEE VERY DRY
CONDITIONS AND THE WINDS WILL BE A LITTLE STRONGER SO IT DOES
APPEAR THAT WE WILL SEE RED FLAG CONDITIONS BOTH AFTERNOONS. FOR
WEDNESDAY THROUGH FRIDAY WE WILL CONTINUE TO SEE PRETTY DRY
CONDITIONS WITH MIN RH`S IN THE TEENS...BUT WINDS WHILE
BREEZY...SHOULD STAY BELOW CRITICAL LEVELS.
&&
.PRELIMINARY POINT TEMPS/POPS...
EL PASO 85 62 85 61 / 10 0 0 0
SIERRA BLANCA 81 57 82 57 / 20 0 0 0
LAS CRUCES 83 54 81 53 / 0 0 0 0
ALAMOGORDO 83 55 81 52 / 10 0 0 0
CLOUDCROFT 59 41 60 40 / 20 0 0 0
TRUTH OR CONSEQUENCES 82 53 81 52 / 0 0 0 0
SILVER CITY 76 46 73 45 / 0 0 0 0
DEMING 84 54 82 52 / 0 0 0 0
LORDSBURG 85 50 81 48 / 0 0 0 0
WEST EL PASO METRO 84 61 84 61 / 0 0 0 0
DELL CITY 83 53 85 53 / 20 0 0 0
FORT HANCOCK 83 58 86 58 / 10 0 0 0
LOMA LINDA 78 57 80 56 / 10 0 0 0
FABENS 84 58 85 58 / 10 0 0 0
SANTA TERESA 84 58 84 57 / 0 0 0 0
WHITE SANDS HQ 83 59 81 56 / 0 0 0 0
JORNADA RANGE 83 51 82 50 / 0 0 0 0
HATCH 85 52 84 50 / 0 0 0 0
COLUMBUS 86 55 83 54 / 0 0 0 0
OROGRANDE 83 59 83 56 / 10 0 0 0
MAYHILL 69 47 71 47 / 20 0 0 0
MESCALERO 70 44 70 45 / 20 0 0 0
TIMBERON 68 46 69 45 / 20 0 0 0
WINSTON 74 43 73 42 / 0 0 0 0
HILLSBORO 79 50 77 49 / 0 0 0 0
SPACEPORT 83 52 82 51 / 0 0 0 0
LAKE ROBERTS 75 39 72 39 / 0 0 0 0
HURLEY 78 47 75 46 / 0 0 0 0
CLIFF 82 42 78 41 / 0 0 0 0
MULE CREEK 80 39 75 39 / 0 0 0 0
FAYWOOD 79 49 77 47 / 0 0 0 0
ANIMAS 85 53 82 51 / 0 0 0 0
HACHITA 86 52 82 51 / 0 0 0 0
ANTELOPE WELLS 84 53 81 51 / 0 0 0 0
CLOVERDALE 80 50 77 48 / 0 0 0 0
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
BRICE
Area Forecast Discussion
National Weather Service Midland/Odessa TX
518 AM CDT SAT APR 23 2016
.DISCUSSION...
See 12Z Aviation Discussion below.
&&
.AVIATION...
VFR conditions will prevail next 24 hours, except in direct
convection. KMAF VAD profiler shows a 45kt LLJ continuing over
the area this AM, w/plenty of high cloud moving thru a dirty
ridge over the area. Sfc flow is forecast yo veer slightly to S
over the next 24 hours, w/a 40+kt LLJ forecast to redevelop after
sunset Saturday night. Forecast soundings develop a widespread cu
field by late morning most terminals, w/bases 4-7 kft agl. As an
upper trough moves thru the region today/tonight, could see some
convection develop over the Big Bend/Lwr Trans Pecos. This will
affect mainly KFST, although the latest HRRR and NAM suggest
convection may develop a little further north.
&&
.PREV DISCUSSION... /issued 453 AM CDT SAT APR 23 2016/
DISCUSSION...
Upper ridging is over the region with an upper low over northern
Mexico that is moving northward. This upper low will bring an
increase in moisture to the area and will allow for a chance of rain
and thunderstorms today across areas primarily south and west of the
Pecos River. Despite an increase in moisture, temperatures will
likely be a couple degrees warmer than yesterday with southerly
winds across the area.
On Sunday, the upper low will move east of the region resulting in
dryer conditions for the area. A surface trough will develop with
west to southwest winds across the area on Sunday allowing for
temperatures to warm up into the upper 80s to lower 90s for much of
the CWA. Similar conditions as Sunday are expected on Monday. An
upper trough will begin moving over the central conus on Tuesday
with the base of the trough moving over the CWA. A surface trough
will also be across the area on Tuesday. The base of the upper
trough moving over the region will result in stronger winds aloft
mixing downward to the surface. This will likely result in critical
fire weather conditions across western portions of the CWA as the
dryline remains to the east. See the fire weather discussion below.
There will be a chance of thunderstorms across the Western Low
Rolling Plains southward to the Lower Trans Pecos Tuesday evening
into Tuesday night as the dryline moves slightly west. The upper
trough will move away from the region on Wednesday with drying
conditions until the next upper trough that is expected to
approach the area next Thursday/Friday.
FIRE WEATHER...
WV imagery shows an upper-lvl trough moving thru NV, and is forecast
to eject into the upper Midwest by 00Z Monday. This will be
followed by a Pac trough making landfall in the PacNW around 06Z
Monday, and quickly digging to the Four Corners by 18Z Tuesday. This
will result in critical fire wx conditions developing as soon as
Sunday across the Guadalupe Mtns/SE NM Plains, and evolving into a
widespread Red Flag day across much of the western fire districts
Tuesday as the Pac trough ejects to the north. While current ERCs
over the Trans Pecos region are below-normal, current Fire Danger
over SE NM and adjacent West Texas is already High-to-Very High,
w/reports of plenty of cured (and tall) fuels west of KINK. As both
upper-lvl troughs translate eastward into the CONUS,
associated leeside troughing on the Front Range will veer 20` winds
to a more westerly direction over the next few days and, combined
w/expected above-normal temps, will only increase Fire Danger and
maintain low RHs. Sunday, as the first trough passes north,
forecast soundings at KGDP mix to around H65, where 25-30kt
westerlies are forecast. These winds will extend some distance
south into West Texas, mainly Culberson, Reeves, and Jeff Davis
Counties. However, throwing much of this into question will be any
convection that develops over the next 24 hours as the trough moves
east thru the region, especially south. For brevity, we`ll issue a
Fire Wx Watch for the areas mentioned above for Sunday, and let
later shifts reassess. Monday looks similar to Sunday, and roughly
the same area will likely be affected. Tuesday looks to be the big
day as the secondary trough ejects just north of West Texas and
Southeast New Mexico.
&&
.PRELIMINARY POINT TEMPS/POPS...
Big Spring 82 60 88 60 / 10 10 10 0
Carlsbad 87 56 87 57 / 10 20 0 0
Dryden 81 62 89 62 / 20 20 10 0
Fort Stockton 83 60 90 59 / 20 20 0 0
Guadalupe Pass 78 55 78 54 / 20 20 0 0
Hobbs 83 56 84 54 / 10 10 0 0
Marfa 76 47 81 47 / 20 20 0 0
Midland Intl Airport 83 62 89 59 / 10 10 0 0
Odessa 83 62 89 60 / 10 10 0 0
Wink 86 61 92 58 / 10 10 0 0
&&
.MAF Watches/Warnings/Advisories...
NM...Fire Weather Watch from Sunday morning through Sunday evening
for Guadalupe Mountains-Southeast Plains.
TX...Fire Weather Watch from Sunday morning through Sunday evening
for Davis/Apache Mountains Area-Guadalupe Mountains-Reeves
County and Upper Trans Pecos-Van Horn and Highway 54
Corridor.
&&
$$
44/80/44
AREA FORECAST DISCUSSION...CORRECTED
NWS MILWAUKEE/SULLIVAN WI
927 PM CDT SUN APR 24 2016
.UPDATE...
18Z GFS AND 23Z HRRR EXPERIMENTAL AND 00Z NAM IS SHOWING A LITTLE
MORE OF A SEVERE WEATHER POTENTIAL FOR MONDAY AFTERNOON AND EARLY
EVENING.
18Z FORECAST SOUNDINGS INDICATE SOME SEVERE HAIL POTENTIAL AND
EVEN A MARGINAL TORNADO POTENTIAL. THE SEVERE WEATHER INDEX CWASP
RISES TO MID TO UPPER 70S. STP VALUES RISE TO AROUND 1 WITH THE
SUPERCELL INDEX AROUND 4. ZERO TO 1 KM MIXED LAYER CAPE RISES TO
AROUND 1400 JOULES/KG. THE GFS INDICATES SOUTHERN WISCONSIN WILL
BE IN THE WARM SECTOR... ALTHOUGH THE SURFACE BOUNDARY HAS BEEN
SAGGING SOUTH OVER THE NORTHEAST 2/3RDS OF THE FORECAST AREA. THIS
WILL BE THE MAIN CONCERN AS THE SURFACE LOW AND WARM FRONT MAY BE
FARTHER SOUTH THAN THE MODELS INDICATE...AS THE MODELS PUSH IT
BACK NORTH LATE TONIGHT AND MONDAY MORNING. MEANWHILE THE 850 MB
LOW TRACK IS ACROSS NORTHERN WISCONSIN...SO THE 850 MB WARM FRONT
WILL BE WELL TO THE NORTH.
IF THE GFS SURFACE TRACK IS CORRECT WITH THE LOW MOVING ACROSS
THE FOND DU LAC AND SHEBOYGAN AREA...THE SETUP WOULD FAVOR A
SEVERE WEATHER POTENTIAL OVER MUCH OF SOUTHERN WISCONSIN AS THE
700 MB SPEED MAX OF 50 KNOTS PUSHES ACROSS SOUTHERN WISCONSIN. THE
SOUTHWEST 850 MB WINDS INCREASE TO 35 KNOTS. MEANWHILE A 50 KNOT
WEST SPEED MAX PUSHES ACROSS BY EVENING WITH THE MAIN MID LEVEL
LOW OVER FAR NORTHERN WISCONSIN.
THE 18Z NAM HAS A MORE SOUTHERN TRACK OF THE SURFACE LOW...WITH
THE SEVERE THREAT THEN LIKELY LIMITED TO THE SOUTHWEST AND FAR
SOUTH.
THE STORM PREDICTION CENTER HAS MUCH OF SOUTHERN WISCONSIN IN A
MARGINAL RISK OF SEVERE THUNDERSTORMS. ANY UPGRADE TO SLIGHT RISK
WOULD LIKELY NEED MORE OF THE MODELS INDICATING THE NORTHERN
TRACK FOR THE SURFACE LOW. EVEN WITH THE HRRR EXPERIMENTALNORTHERLY
TRACK MUCH OF THE STRONG THUNDERSTORMS DEVELOP JUST SOUTH MORE
ACROSS NORTHERN ILLINOIS.
THE 00Z NAM IS STILL PUSHING THE BOUNDARY BACK NORTH MONDAY
MORNING WITH THE WARM FRONT APPRACHING THE DELLS TO JUST SOUTH OF
MILWAUKEE BY 1 PM. THE 00Z NAM ALSO SEEMS TO BE TRENDING TO MORE
OF THE 18Z GFS TRACK...SO STAY TUNED.
&&
.AVIATION/06Z TAFS/...
VFR CONDITIONS TO CONTINUE THIS EVENING AND OVERNIGHT ACROSS THE TAF
SITES. SOUTHWESTERLY WINDS OF 25 TO 35 KTS BETWEEN 1-2 KFT WILL
CREATE MARGINAL CONDITIONS FOR WIND SHEAR LATE THIS EVENING INTO THE
EARLY MORNING HOURS.
SHOWERS AND MAYBE A RUMBLE OF THUNDER ARE POSSIBLE LATE TONIGHT INTO
MONDAY MORNING AS AN UPPER AIR DISTURBANCE TRACKS THROUGH THE AREA.
VFR CIGS EXPECTED TO CONTINUE WITH THIS FEATURE.
A FRONT WILL STALL OVER CENTRAL WI DURING THE DAY MONDAY AND BE THE
FOCUS FOR POSSIBLE SHOWERS AND THUNDERSTORMS...WITH MVFR CONDITIONS
POSSIBLE AT TIMES. ANOTHER FRONT COULD BRING THUNDERSTORMS TO THE
REST OF SOUTHERN WI LATE MONDAY AFTERNOON/EVENING. SOUTH TO
SOUTHWESTERLY WINDS WILL GUST BETWEEN 15 TO 25 KTS LATE MONDAY
MORNING THROUGH THE AFTERNOON.
&&
.MARINE...
EASTERLY WINDS WILL VEER TO THE SOUTHEAST TO SOUTH ON MONDAY AHEAD
OF AN APPROACHING LOW PRESSURE SYSTEM. ONCE THE LOW PASSES
BY...STRONGER NORTHEAST WINDS WILL PUSH DOWN THE LAKE LATE MONDAY
NIGHT INTO TUESDAY. THIS COULD RESULT IN SMALL CRAFT ADVISORY
CONDITIONS...ESPECIALLY NORTH OF MILWAUKEE. WINDS AND WAVES WILL
DECREASE BY TUESDAY NIGHT AS HIGH PRESSURE WITH AN EASTERLY FLOW
SETTLES ACROSS THE REGION.
&&
.PREV DISCUSSION... /ISSUED 307 PM CDT SUN APR 24 2016/
TONIGHT AND MONDAY... FORECAST CONFIDENCE MEDIUM.
MODELS ARE HAVING A HARD TIME RESOLVING THE SUBTLE FORCING FEATURES
JUTTING OUT AHEAD OF A CLOSED UPPER LOW THAT IS SLOWLY TRAVERSING
ACROSS THE PLAINS. CHANCES FOR LIGHT SHOWERS AND MAYBE A RUMBLE OF
THUNDER TOWARD CENTRAL WI INCLUDING FOND DU LAC AND SHEBOYGAN SHOULD
BE DIMINISHING EARLY THIS EVENING AS UPPER LEVEL RIDGING WORKS
FARTHER INTO SOUTHERN WI. THESE WERE ASSOCIATED WITH STEADY 850-
700MB WARM AIR ADVECTION AND FRONTOGENESIS.
LATER TONIGHT...SHORTWAVE ENERGY FROM THE APPROACHING UPPER LOW WILL
SWING FROM WEST TO EAST ACROSS SOUTHERN WI... PROBABLY BETWEEN 4 AM
AND 10 AM. THIS COULD BE ENOUGH FORCING FOR SOME SHOWERS. THERE WILL
BE SOME ELEVATED INSTABILITY PRESENT WITH THE STEEP UPPER LEVEL
LAPSE RATES AND EXTRA LIFT FROM THE LOW LEVEL JET... SO KEPT SMALL
MENTION OF THUNDER.
WE ARE STILL WAITING FOR THE SURFACE WARM FRONT TO CREEP INTO
SOUTHWEST WI AND BRING TEMPS UP A COUPLE MORE DEGREES INTO THE UPPER
70S LATE THIS AFTERNOON. THIS FRONT WILL CONTINUE TO BATTLE THE
COOLER AIR MASS INFLUENCED BY LAKE MICHIGAN... BUT MODELS AGREE ON
BRINGING IT NORTHWARD UP TO SOUTHERN FOND DU LAC AND SHEBOYGAN
COUNTIES BY LATE TONIGHT. THIS MEANS TEMPERATURES WILL BE WARMER
NEAR LAKE MICHIGAN ON MONDAY.
THIS FRONT WILL SIT OVER CENTRAL WI ON MONDAY AND BE THE FOCUS FOR
SHOWERS AND ISOLATED THUNDERSTORMS ONCE AGAIN. THE SURFACE LOW IS
EXPECTED TO MOVE INTO SOUTH CENTRAL WI SOMETIME ON MONDAY. LOW LEVEL
FRONTOGENESIS WILL SWEEP THROUGH THE AREA DURING THE LATE AFTERNOON.
SOME MODELS GENERATE CONVECTION ALONG THIS FRONT IN SOUTH
CENTRAL/SOUTHEAST WI WHILE OTHERS WAIT FOR IT TO CLEAR WI AND THEN
GENERATE PRECIP ALONG IT TO OUR SOUTHEAST DURING THE EVENING.
THE NAM CONTINUES TO BE ONE OF THE MORE ROBUST MODELS WITH
GENERATING HIGH CAPE UP TO 2000 J/KG WHILE THE GFS IS MORE MODERATE
AROUND 1000 J/KG. NONETHELESS THE SHEAR VALUES OF 30 TO 40 KNOTS
SUPPORT ORGANIZED CONVECTION. SPC KEPT SOUTHERN WI IN THE MARGINAL
RISK FOR SEVERE STORMS FOR THE ISOLATED POTENTIAL.
MONDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM.
ANY ONGOING CONVECTION THAT FIRES LATE IN THE AFTERNOON ON MONDAY
WILL QUICKLY EXIT EAST DURING THE EVENING. THE COLD FRONT
ASSOCIATED WITH THE WEAKENING LOW WILL BE OVER THE SOUTHEAST RIGHT
AROUND 00Z TUESDAY...WITH A TRIPLE POINT ASSOCIATED WITH THE
WARM/OCCLUDED FRONT UP AROUND FOND DU LAC AND SHEBOYGAN. ALL THIS
SHOULD BE PUSHING INTO LOWER MICHIGAN BY 03Z TUESDAY. THERE IS A
VERY MARGINAL THREAT THAT SOME OF THESE STORMS COULD BE SEVERE
GIVEN THE POTENTIAL FOR FAVORABLE INSTABILITY AND DEEP LAYER SHEAR
ON THE ORDER OF 30-40KTS. HOWEVER...TOO MUCH CLOUDINESS MAY BE AN
ISSUE AND WILL LIMIT HOW UNSTABLE WE GET. AREAS WEST OF MADISON
WILL BE DRYING OUT BY THE START OF THIS PERIOD.
TUESDAY INTO TUESDAY NIGHT...FORECAST CONFIDENCE IS HIGH.
SFC HIGH PRESSURE WILL BUILD INTO THE AREA...BRINGING A MUCH
COOLER NORTHEAST THEN EASTERLY FLOW DURING THE PERIOD. COOLEST
READINGS OF COURSE WILL BE FELT ACROSS THE EASTERN HALF OF THE
FORECAST AREA DUE TO THE INFLUENCE OF THE COLD LAKE MICHIGAN
WATERS. BY LATE TUESDAY NIGHT...THE MID LEVEL RIDGE THAT BROUGHT
THE DRY CONDITIONS WILL PUSH EAST...ALLOWING THE ENERGY OF A
DECENT MID LEVEL CIRCULATION TO IMPINGE ON SOUTHWEST WISCONSIN. WE
COULD SEE SOME RAIN CHANCES ENTER THAT AREA AFTER ABOUT 4 AM.
WEDNESDAY THROUGH THURSDAY...FORECAST CONFIDENCE IS MEDIUM.
THAT MID LEVEL WAVE WILL BE VERY SLOW TO MOVE THROUGH THE
REGION DURING THIS PERIOD. THE UPPER CIRCULATION WILL TRAVEL
FROM NEBRASKA WED MORNING TO NRN IL BY MID DAY ON THURSDAY. THE
ASSOCIATED SURFACE LOW WILL REMAIN SOUTH OF WISCONSIN...KEEPING US
ON THE CHILLY SIDE OF THINGS. RAIN WILL BEGIN SPREADING NORTH ON
WEDNESDAY BUT WILL BE HINDERED BY A VERY DRY EASTERLY FLOW. THIS
CLASSIC SET UP WILL LIKELY MEAN OUR NE FORECAST AREA WILL BE DRY
ON WED...BUT COLD DUE TO THE FLOW OFF THE LAKE. KEPT A SMALL
CHANCE OF RAIN UP THERE JUST IN CASE IT HAS MORE MOMENTUM THAN
EXPECTED. THE RAIN SHOULD EVENTUALLY OVERSPREAD ALL OF THE AREA
WEDNESDAY NIGHT INTO THURSDAY...BEFORE FINALLY ENDING THURSDAY
AFTERNOON. NO THUNDER. JUST A CHILLY RAIN.
THURSDAY NIGHT THROUGH FRIDAY NIGHT...FORECAST CONFIDENCE IS
MEDIUM.
HIGH PRESSURE SHOULD KEEP MUCH OF THE AREA DRY THROUGH THE PERIOD.
MUCH LIKE THE PREVIOUS SYSTEM...MID LEVEL RIDGING WILL BREAK DOWN
LATE FRIDAY NIGHT WITH ANOTHER CIRCULATION APPROACHING...BRINGING A
CHANCE OF RAIN TO THE AREA AFTER MIDNIGHT.
SATURDAY AND SUNDAY...FORECAST CONFIDENCE IS MEDIUM.
ANOTHER MID LEVEL CIRCULATION WILL DRIFT ACROSS THE AREA WITH THE
SURFACE LOW REMAINING TO OUR SOUTH. THIS BRINGS ANOTHER PERIOD OF
POTENTIAL RAIN FOR NEXT WEEKEND...AND GIVEN THE POSITION OF THE
SURFACE LOW...THE COOL EAST TO NORTHEAST WINDS WITH HIGHS IN THE
40S AND 50S WILL CONTINUE.
AVIATION/00Z TAFS/...
VFR CONDITIONS EXPECTED THROUGH THIS EVENING. CHANCE OF LIGHT
RAIN/SPRINKLES TODAY AND THIS EVENING TOWARD FOND DU LAC AND
SHEBOYGAN.
SOUTHWESTERLY WINDS OF 25 TO 35 KT BETWEEN 1000 AND 2000 FEET WILL
CREATE MARGINAL CONDITIONS FOR WIND SHEAR ONCE AGAIN LATE THIS
EVENING INTO THE EARLY MORNING HOURS.
SHOWERS AND MAYBE A RUMBLE OF THUNDER ARE POSSIBLE LATE TONIGHT INTO
MONDAY MORNING AS AN UPPER AIR DISTURBANCE TRACKS THROUGH THE AREA.
VFR CIGS EXPECTED WITH THIS FEATURE.
A FRONT WILL STALL OVER CENTRAL WI DURING THE DAY MONDAY AND BE THE
FOCUS FOR POSSIBLE SHOWERS AND THUNDERSTORMS AND MVFR CONDITIONS AT
TIMES. ANOTHER FRONT COULD BRING THUNDERSTORMS TO THE REST OF
SOUTHERN WI LATE MONDAY AFTERNOON/EVENING.
MARINE...
EASTERLY WINDS WILL VEER TO THE SOUTHEAST TO SOUTH ON MONDAY AHEAD
OF AN APPROACHING LOW PRESSURE SYSTEM. ONCE THE LOW PASSES
BY...STRONGER NORTHEAST WINDS WILL PUSH DOWN THE LAKE LATE MONDAY
NIGHT INTO TUESDAY. THIS COULD RESULT IN SMALL CRAFT ADVISORY
CONDITIONS...ESPECIALLY NORTH OF MILWAUKEE. WINDS AND WAVES WILL
DECREASE BY TUESDAY NIGHT AS HIGH PRESSURE WITH AN EASTERLY FLOW
SETTLES ACROSS THE REGION.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...HENTZ
TONIGHT/MONDAY AND AVIATION/MARINE...MRC
MONDAY NIGHT THROUGH SUNDAY...DAVIS
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
903 PM CDT SUN APR 24 2016
.UPDATE...
18Z GFS AND 23Z HRRR EXPERIMENTAL AND 00Z NAM IS SHOWING A LITTLE
MORE OF A SEVERE WEATHER POTENTIAL FOR MONDAY AFTERNOON AND EARLY
EVENING.
18Z FORECAST SOUNDINGS INDICATE SOME SEVERE HAIL POTENTIAL AND
EVEN A MARGINAL TORNADO POTENTIAL. THE SEVERE WEATHER INDEX CWASP
RISES TO MID TO UPPER 70S. STP VALUES RISE TO AROUND 4. ZERO TO 1
KM MIXED LAYER CAPE RISES TO AROUND 1400 JOULES/KG. THE GFS
INDICATES SOUTHERN WISCONSIN WILL BE IN THE WARM SECTOR...
ALTHOUGH THE SURFACE BOUNDARY HAS BEEN SAGGING SOUTH OVER THE
NORTHEAST 2/3RDS OF THE FORECAST AREA. THIS WILL BE THE MAIN
CONCERN AS THE SURFACE LOW AND WARM FRONT MAY BE FARTHER SOUTH
THAN THE MODELS INDICATE...AS THE MODELS PUSH IT BACK NORTH LATE
TONIGHT AND MONDAY MORNING. MEANWHILE THE 850 MB LOW TRACK IS
ACROSS NORTHERN WISCONSIN...SO THE 850 MB WARM FRONT WILL BE WELL TO
THE NORTH.
IF THE GFS SURFACE TRACK IS CORRECT WITH THE LOW MOVING ACROSS
THE FOND DU LAC AND SHEBOYGAN AREA...THE SETUP WOULD FAVOR A
SEVERE WEATHER POTENTIAL OVER MUCH OF SOUTHERN WISCONSIN AS THE
700 MB SPEED MAX OF 50 KNOTS PUSHES ACROSS SOUTHERN WISCONSIN. THE
SOUTHWEST 850 MB WINDS INCREASE TO 35 KNOTS. MEANWHILE A 50 KNOT
WEST SPEED MAX PUSHES ACROSS BY EVENING WITH THE MAIN MID LEVEL
LOW OVER FAR NORTHERN WISCONSIN.
THE 18Z NAM HAS A MORE SOUTHERN TRACK OF THE SURFACE LOW...WITH
THE SEVERE THREAT THEN LIKELY LIMITED TO THE SOUTHWEST AND FAR
SOUTH.
THE STORM PREDICTION CENTER HAS MUCH OF SOUTHERN WISCONSIN IN A
MARGINAL RISK OF SEVERE THUNDERSTORMS. ANY UPGRADE TO SLIGHT RISK
WOULD LIKELY NEED MORE OF THE MODELS INDICATING THE NORTHERN
TRACK FOR THE SURFACE LOW. EVEN WITH THE HRRR EXPERIMENTALNORTHERLY
TRACK MUCH OF THE STRONG THUNDERSTORMS DEVELOP JUST SOUTH MORE
ACROSS NORTHERN ILLINOIS.
THE 00Z NAM IS STILL PUSHING THE BOUNDARY BACK NORTH MONDAY
MORNING WITH THE WARM FRONT APPRACHING THE DELLS TO JUST SOUTH OF
MILWAUKEE BY 1 PM. THE 00Z NAM ALSO SEEMS TO BE TRENDING TO MORE
OF THE 18Z GFS TRACK...SO STAY TUNED.
&&
.AVIATION/06Z TAFS/...
VFR CONDITIONS TO CONTINUE THIS EVENING AND OVERNIGHT ACROSS THE TAF
SITES. SOUTHWESTERLY WINDS OF 25 TO 35 KTS BETWEEN 1-2 KFT WILL
CREATE MARGINAL CONDITIONS FOR WIND SHEAR LATE THIS EVENING INTO THE
EARLY MORNING HOURS.
SHOWERS AND MAYBE A RUMBLE OF THUNDER ARE POSSIBLE LATE TONIGHT INTO
MONDAY MORNING AS AN UPPER AIR DISTURBANCE TRACKS THROUGH THE AREA.
VFR CIGS EXPECTED TO CONTINUE WITH THIS FEATURE.
A FRONT WILL STALL OVER CENTRAL WI DURING THE DAY MONDAY AND BE THE
FOCUS FOR POSSIBLE SHOWERS AND THUNDERSTORMS...WITH MVFR CONDITIONS
POSSIBLE AT TIMES. ANOTHER FRONT COULD BRING THUNDERSTORMS TO THE
REST OF SOUTHERN WI LATE MONDAY AFTERNOON/EVENING. SOUTH TO
SOUTHWESTERLY WINDS WILL GUST BETWEEN 15 TO 25 KTS LATE MONDAY
MORNING THROUGH THE AFTERNOON.
&&
.MARINE...
EASTERLY WINDS WILL VEER TO THE SOUTHEAST TO SOUTH ON MONDAY AHEAD
OF AN APPROACHING LOW PRESSURE SYSTEM. ONCE THE LOW PASSES
BY...STRONGER NORTHEAST WINDS WILL PUSH DOWN THE LAKE LATE MONDAY
NIGHT INTO TUESDAY. THIS COULD RESULT IN SMALL CRAFT ADVISORY
CONDITIONS...ESPECIALLY NORTH OF MILWAUKEE. WINDS AND WAVES WILL
DECREASE BY TUESDAY NIGHT AS HIGH PRESSURE WITH AN EASTERLY FLOW
SETTLES ACROSS THE REGION.
&&
.PREV DISCUSSION... /ISSUED 307 PM CDT SUN APR 24 2016/
TONIGHT AND MONDAY... FORECAST CONFIDENCE MEDIUM.
MODELS ARE HAVING A HARD TIME RESOLVING THE SUBTLE FORCING FEATURES
JUTTING OUT AHEAD OF A CLOSED UPPER LOW THAT IS SLOWLY TRAVERSING
ACROSS THE PLAINS. CHANCES FOR LIGHT SHOWERS AND MAYBE A RUMBLE OF
THUNDER TOWARD CENTRAL WI INCLUDING FOND DU LAC AND SHEBOYGAN SHOULD
BE DIMINISHING EARLY THIS EVENING AS UPPER LEVEL RIDGING WORKS
FARTHER INTO SOUTHERN WI. THESE WERE ASSOCIATED WITH STEADY 850-
700MB WARM AIR ADVECTION AND FRONTOGENESIS.
LATER TONIGHT...SHORTWAVE ENERGY FROM THE APPROACHING UPPER LOW WILL
SWING FROM WEST TO EAST ACROSS SOUTHERN WI... PROBABLY BETWEEN 4 AM
AND 10 AM. THIS COULD BE ENOUGH FORCING FOR SOME SHOWERS. THERE WILL
BE SOME ELEVATED INSTABILITY PRESENT WITH THE STEEP UPPER LEVEL
LAPSE RATES AND EXTRA LIFT FROM THE LOW LEVEL JET... SO KEPT SMALL
MENTION OF THUNDER.
WE ARE STILL WAITING FOR THE SURFACE WARM FRONT TO CREEP INTO
SOUTHWEST WI AND BRING TEMPS UP A COUPLE MORE DEGREES INTO THE UPPER
70S LATE THIS AFTERNOON. THIS FRONT WILL CONTINUE TO BATTLE THE
COOLER AIR MASS INFLUENCED BY LAKE MICHIGAN... BUT MODELS AGREE ON
BRINGING IT NORTHWARD UP TO SOUTHERN FOND DU LAC AND SHEBOYGAN
COUNTIES BY LATE TONIGHT. THIS MEANS TEMPERATURES WILL BE WARMER
NEAR LAKE MICHIGAN ON MONDAY.
THIS FRONT WILL SIT OVER CENTRAL WI ON MONDAY AND BE THE FOCUS FOR
SHOWERS AND ISOLATED THUNDERSTORMS ONCE AGAIN. THE SURFACE LOW IS
EXPECTED TO MOVE INTO SOUTH CENTRAL WI SOMETIME ON MONDAY. LOW LEVEL
FRONTOGENESIS WILL SWEEP THROUGH THE AREA DURING THE LATE AFTERNOON.
SOME MODELS GENERATE CONVECTION ALONG THIS FRONT IN SOUTH
CENTRAL/SOUTHEAST WI WHILE OTHERS WAIT FOR IT TO CLEAR WI AND THEN
GENERATE PRECIP ALONG IT TO OUR SOUTHEAST DURING THE EVENING.
THE NAM CONTINUES TO BE ONE OF THE MORE ROBUST MODELS WITH
GENERATING HIGH CAPE UP TO 2000 J/KG WHILE THE GFS IS MORE MODERATE
AROUND 1000 J/KG. NONETHELESS THE SHEAR VALUES OF 30 TO 40 KNOTS
SUPPORT ORGANIZED CONVECTION. SPC KEPT SOUTHERN WI IN THE MARGINAL
RISK FOR SEVERE STORMS FOR THE ISOLATED POTENTIAL.
MONDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM.
ANY ONGOING CONVECTION THAT FIRES LATE IN THE AFTERNOON ON MONDAY
WILL QUICKLY EXIT EAST DURING THE EVENING. THE COLD FRONT
ASSOCIATED WITH THE WEAKENING LOW WILL BE OVER THE SOUTHEAST RIGHT
AROUND 00Z TUESDAY...WITH A TRIPLE POINT ASSOCIATED WITH THE
WARM/OCCLUDED FRONT UP AROUND FOND DU LAC AND SHEBOYGAN. ALL THIS
SHOULD BE PUSHING INTO LOWER MICHIGAN BY 03Z TUESDAY. THERE IS A
VERY MARGINAL THREAT THAT SOME OF THESE STORMS COULD BE SEVERE
GIVEN THE POTENTIAL FOR FAVORABLE INSTABILITY AND DEEP LAYER SHEAR
ON THE ORDER OF 30-40KTS. HOWEVER...TOO MUCH CLOUDINESS MAY BE AN
ISSUE AND WILL LIMIT HOW UNSTABLE WE GET. AREAS WEST OF MADISON
WILL BE DRYING OUT BY THE START OF THIS PERIOD.
TUESDAY INTO TUESDAY NIGHT...FORECAST CONFIDENCE IS HIGH.
SFC HIGH PRESSURE WILL BUILD INTO THE AREA...BRINGING A MUCH
COOLER NORTHEAST THEN EASTERLY FLOW DURING THE PERIOD. COOLEST
READINGS OF COURSE WILL BE FELT ACROSS THE EASTERN HALF OF THE
FORECAST AREA DUE TO THE INFLUENCE OF THE COLD LAKE MICHIGAN
WATERS. BY LATE TUESDAY NIGHT...THE MID LEVEL RIDGE THAT BROUGHT
THE DRY CONDITIONS WILL PUSH EAST...ALLOWING THE ENERGY OF A
DECENT MID LEVEL CIRCULATION TO IMPINGE ON SOUTHWEST WISCONSIN. WE
COULD SEE SOME RAIN CHANCES ENTER THAT AREA AFTER ABOUT 4 AM.
WEDNESDAY THROUGH THURSDAY...FORECAST CONFIDENCE IS MEDIUM.
THAT MID LEVEL WAVE WILL BE VERY SLOW TO MOVE THROUGH THE
REGION DURING THIS PERIOD. THE UPPER CIRCULATION WILL TRAVEL
FROM NEBRASKA WED MORNING TO NRN IL BY MID DAY ON THURSDAY. THE
ASSOCIATED SURFACE LOW WILL REMAIN SOUTH OF WISCONSIN...KEEPING US
ON THE CHILLY SIDE OF THINGS. RAIN WILL BEGIN SPREADING NORTH ON
WEDNESDAY BUT WILL BE HINDERED BY A VERY DRY EASTERLY FLOW. THIS
CLASSIC SET UP WILL LIKELY MEAN OUR NE FORECAST AREA WILL BE DRY
ON WED...BUT COLD DUE TO THE FLOW OFF THE LAKE. KEPT A SMALL
CHANCE OF RAIN UP THERE JUST IN CASE IT HAS MORE MOMENTUM THAN
EXPECTED. THE RAIN SHOULD EVENTUALLY OVERSPREAD ALL OF THE AREA
WEDNESDAY NIGHT INTO THURSDAY...BEFORE FINALLY ENDING THURSDAY
AFTERNOON. NO THUNDER. JUST A CHILLY RAIN.
THURSDAY NIGHT THROUGH FRIDAY NIGHT...FORECAST CONFIDENCE IS
MEDIUM.
HIGH PRESSURE SHOULD KEEP MUCH OF THE AREA DRY THROUGH THE PERIOD.
MUCH LIKE THE PREVIOUS SYSTEM...MID LEVEL RIDGING WILL BREAK DOWN
LATE FRIDAY NIGHT WITH ANOTHER CIRCULATION APPROACHING...BRINGING A
CHANCE OF RAIN TO THE AREA AFTER MIDNIGHT.
SATURDAY AND SUNDAY...FORECAST CONFIDENCE IS MEDIUM.
ANOTHER MID LEVEL CIRCULATION WILL DRIFT ACROSS THE AREA WITH THE
SURFACE LOW REMAINING TO OUR SOUTH. THIS BRINGS ANOTHER PERIOD OF
POTENTIAL RAIN FOR NEXT WEEKEND...AND GIVEN THE POSITION OF THE
SURFACE LOW...THE COOL EAST TO NORTHEAST WINDS WITH HIGHS IN THE
40S AND 50S WILL CONTINUE.
AVIATION/00Z TAFS/...
VFR CONDITIONS EXPECTED THROUGH THIS EVENING. CHANCE OF LIGHT
RAIN/SPRINKLES TODAY AND THIS EVENING TOWARD FOND DU LAC AND
SHEBOYGAN.
SOUTHWESTERLY WINDS OF 25 TO 35 KT BETWEEN 1000 AND 2000 FEET WILL
CREATE MARGINAL CONDITIONS FOR WIND SHEAR ONCE AGAIN LATE THIS
EVENING INTO THE EARLY MORNING HOURS.
SHOWERS AND MAYBE A RUMBLE OF THUNDER ARE POSSIBLE LATE TONIGHT INTO
MONDAY MORNING AS AN UPPER AIR DISTURBANCE TRACKS THROUGH THE AREA.
VFR CIGS EXPECTED WITH THIS FEATURE.
A FRONT WILL STALL OVER CENTRAL WI DURING THE DAY MONDAY AND BE THE
FOCUS FOR POSSIBLE SHOWERS AND THUNDERSTORMS AND MVFR CONDITIONS AT
TIMES. ANOTHER FRONT COULD BRING THUNDERSTORMS TO THE REST OF
SOUTHERN WI LATE MONDAY AFTERNOON/EVENING.
MARINE...
EASTERLY WINDS WILL VEER TO THE SOUTHEAST TO SOUTH ON MONDAY AHEAD
OF AN APPROACHING LOW PRESSURE SYSTEM. ONCE THE LOW PASSES
BY...STRONGER NORTHEAST WINDS WILL PUSH DOWN THE LAKE LATE MONDAY
NIGHT INTO TUESDAY. THIS COULD RESULT IN SMALL CRAFT ADVISORY
CONDITIONS...ESPECIALLY NORTH OF MILWAUKEE. WINDS AND WAVES WILL
DECREASE BY TUESDAY NIGHT AS HIGH PRESSURE WITH AN EASTERLY FLOW
SETTLES ACROSS THE REGION.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...HENTZ
TONIGHT/MONDAY AND AVIATION/MARINE...MRC
MONDAY NIGHT THROUGH SUNDAY...DAVIS
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1104 PM PDT SUN APR 24 2016
.SYNOPSIS....WIND ADVISORY ALONG THE COAST THIS EVENING WITH GUSTY
NORTHWEST WINDS. CONTINUED COOL AND BREEZY ON MONDAY...OTHERWISE
DRY AND SEASONABLY COOL WEATHER IS FORECAST THROUGH TUESDAY. THERE
IS A CHANCE OF SHOWERS WEDNESDAY AND WEDNESDAY NIGHT AS A WEATHER
SYSTEM TRACKS ACROSS CALIFORNIA FROM NORTH TO SOUTH. LONG RANGE
TRENDS SUGGEST A SIGNIFICANT WARMING TREND BY LATE IN THE WEEK AND
INTO NEXT WEEKEND.
&&
.DISCUSSION...AS OF 8:49 PM PDT SUNDAY...A WIND ADVISORY REMAINS
IN EFFECT FOR COASTAL AREAS TIL MIDNIGHT TONIGHT. POST COLD
FRONTAL W-NW WINDS ARE WELL LINKED IN THE VERTICAL. PLUS SURFACE
WINDS ARE BEING DRIVEN BY MODERATE TO STRONG SURFACE PRESSURE
GRADIENTS ACV-SFO 7.2 MB AND SFO-SAC 4 MB. A MODERATE TO STRONG
UPPER LEVEL TROUGH ADVANCING EASTWARD OVER THE WEST COAST WILL
BECOME A CLOSED OFF LOW OVER NEVADA MONDAY THE LOW THEN REACHING
NORTHERN COLORADO TUESDAY.
SURFACE BASED INSTABILITY AROUND THE BAY AREA AND NORTH CENTRAL
COAST DURING THE AFTERNOON LED TO A FEW CUMULUS CLOUD BUILD-UPS
WELL INLAND AWAY FROM THE WATER. SINCE LATE AFTERNOON CONVECTIVE
INHIBITION OR NEGATIVE BUOYANCY HAS SETTLED IN OVER THE ENTIRE
REGION; IT SHOULD REMAIN DRY TONIGHT. RECENT HRRR AND NAM MODEL
FORECASTS HINT THAT THERE MAY BE AN ISOLATED SPRINKLE OR SHOWER
BETWEEN 11 PM TONIGHT - 5 AM MONDAY BUT NOT ENOUGH FOR AN UPDATE.
CLOSE TO OPTIMUM VERTICAL MIXING MAINTAINS THROUGH TONIGHT THUS
NOT ONLY DRYING OUT THE ATMOSPHERE BUT IT SHOULD HELP HOLD TEMPS
UP THROUGH THE NIGHT AS WELL. NORTH BAY INTERIOR VALLEYS WHERE
SURFACE WINDS DE-COUPLE COULD HAVE UPPER 30S MONDAY MORNING.
A PROGRESSIVE WX PATTERN CONTINUES ACROSS THE EASTERN PACIFIC INTO
NORTH AMERICA. 500 MB HEIGHTS WILL REBOUND BACK TO NORMAL OR SLIGHTLY
ABOVE TUESDAY THEN LOWER WED-THU AS ANOTHER TROUGH WITH SHOWERS SWINGS
EASTWARD OVER THE AREA. THERE`S RECENTLY BEEN GOOD RUN TO RUN MODEL
AGREEMENT INDICATING ABOVE NORMAL RIDGING RETURNS TO THE AREA LATE
THIS WEEK BUT THERE`S SOME DISAGREEMENT THEREAFTER AS TO HOW QUICKLY
THE 500 MB HEIGHT RIDGE DISSIPATES EARLY NEXT WEEK. AS MENTIONED IN
THE PREVIOUS DISCUSSION THERE`S POTENTIAL FOR A SIGNIFICANT WARMING
TREND LATE IN THE WEEK AND NEXT WEEKEND.
&&
.PREV DISCUSSION...AS OF 3:00 PM PDT SUNDAY...WIND ADVISORY IN EFFECT
FOR COASTAL AREAS. SO FAR WE`VE SEEN GUSTS TO AROUND 45 MPH AT PT
REYES WITH 43 MPH KSFO AND SOME 35-40 MPH IN THE MARIN HILLS.
WINDS ARE FORECAST TO PEAK LATE THIS AFTERNOON AND EARLY EVENING
AS THE MAIN TROUGH AXIS PASSES OVERHEAD AND STRONGER COLD
ADVECTION ARRIVES OVER THE AREA. MUCH LIGHTER WINDS ARE OCCURRING
JUST A FEW MILES INLAND WITH AFTERNOON READINGS INTO THE 60S.
SKIES WILL BE MOSTLY CLEAR OVERNIGHT AND CHILLY LATE APRIL
TEMPERATURES ARE IN STORE BUT ENOUGH BOUNDARY LAYER MIXING TO
PRECLUDE ANYTHING TOO COLD.
MONDAY WILL BE A PARTLY CLOUDY AND SEASONABLY COOL DAY WITH SOME
CONTINUED BLUSTERY WINDS RIGHT ALONG THE COAST AND HILLS AS
ANOTHER COLD SHORTWAVE PASSES TO OUR EAST AND GENERATES SHOWERS
OVER THE SIERRA. HIGHS ON MONDAY WILL STAY IN THE 60S ONCE
AGAIN...EVEN FOR INLAND AREAS WHERE DAYTIME NORMAL ARE NOW AROUND
THE MIDDLE 70S.
NO BIG CHANGES FOR TUESDAY BUT SOME SHORTWAVE RIDGING WILL ALLOW
FOR A FEW DEGREES OF WARMING WITH SOME LOWER 70S SHOWING UP BY
TUESDAY AFTERNOON.
BY EARLY WEDS MORNING SHOWER CHANCES RETURN TO THE FORECAST WITH
THE MODELS SHOWING SOME LIGHT SHOWERS AS EARLY AS 12Z WEDS FROM A
COLD BUT FAIRLY DRY SYSTEM APPROACHING FROM THE NW. THE ECMWF HAS
HAD THIS SCENARIO FEATURED FOR DAYS NOW BUT THE OVERALL TREND HAS
BEEN DRIER. NONETHELESS IT DOES LOOK LIKE A PRETTY GOOD CHANCE OF
SHOWERS FOR WEDS. IN GENERAL THE MODELS HAVE BEEN PAINTING THE
SANTA CRUZ MTNS AND BIG SUR HILLS AS THE BEST LOCATIONS TO SEE
SHOWERS ON WEDS...ALONG WITH SOME OF THE INTERIOR HILLS DUE TO
CONVECTIVE AFTERNOON SHOWERS. FOR NOW THE FORECAST IS FAIRLY
BROADBRUSH WITH CHANCE OF SHOWERS AND QPF TOTALS 0.15-0.25 ON
AVERAGE. THE WEDS SYSTEM WILL BE COLD AS WELL WITH 850 MB TEMPS
DOWN TO AROUND 4 CELSIUS. ANY SHOWERS WILL LIKELY END AS THE SUN
GOES DOWN WEDS EVENING.
THURSDAY WILL BE A DRY BUT COOL DAY AS THE TROUGH MOVES EAST WITH
CONTINUED DRY BUT CHILLY NORTHERLY WINDS.
MODELS NOW STARTING TO SHOW A POTENTIALLY SIGNIFICANT WARMING
TREND GETTING UNDERWAY BY FRIDAY BUT PEAKING LATER NEXT WEEKEND AS
A RIDGE BUILDS...THERMAL TROUGH PUSHES TO THE COAST AND PERIODS OF
OFFSHORE WINDS ENSUE. ECMWF HAS 850 MB TEMPS TO 18 CELSIUS BY
THIS TIME NEXT WEEKEND.
&&
.AVIATION...AS OF 10:55 PM PDT SUNDAY...MAINLY HIGH CLOUDS EXPECTED
ACROSS AREA TERMINALS THROUGH TONIGHT WITH PATCHY CLOUDS FORMING
LOCALLY OVER THE HILLS. GUSTY WEST WINDS WILL PREVAIL THROUGH
TONIGHT AND INTO MONDAY AS THE TROUGH AXIS MOVES ACROSS THE
REGION. BREEZY CONDITIONS AND COLD AIR ADVECTION WILL KEEP STRATUS
TO A MINIMUM ALONG THE COAST. HIGH CONFIDENCE.
VICINITY OF KSFO...VFR CONDITIONS EXPECTED THROUGH THE PERIOD.
WEST WINDS SUSTAINED BETWEEN 15 TO 25 KT WITH GUSTS TO 30 KT WILL
PREVAIL THROUGH TONIGHT INTO MONDAY. HIGH CONFIDENCE.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY TERMINALS...VFR CONDITIONS EXPECTED THROUGH THE PERIOD.
WEST WINDS SUSTAINED AROUND 15 KT WITH GUSTS AROUND 25 KT WILL
PREVAIL THROUGH TONIGHT. HIGH CONFIDENCE.
&&
.MARINE...AS OF 9:00 PM PDT SUNDAY...FREQUENT GALE FORCE GUSTS
ARE EXPECTED THROUGH MONDAY EVENING AS COLD AIR RUSHES IN BEHIND A
DEPARTING FRONT. THESE STRONG WINDS WILL RESULT IN STEEP CHOPPY
SEAS ACROSS THE COASTAL WATERS THROUGH MONDAY EVENING. WINDS WILL
EASE SLIGHTLY TUESDAY BUT ARE ANTICIPATED TO INCREASE ONCE AGAIN
THE SECOND HALF OF THE WEEK.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...WIND ADVISORY...COASTAL ZONES FOR SF BAY AREA AND
SOUTHERN MONTEREY BAY AND BIG SUR COAST TIL MIDNIGHT
GLW...PT ARENA TO PT REYES 0-10 NM
GLW...PT REYES TO PIGEON PT 0-10 NM
GLW...PIGEON PT TO PT PINOS 0-10 NM
GLW...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
GLW...PT ARENA TO PIGEON PT 10-60 NM
GLW...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM
SCA...ROUGH BAR ADVISORY FOR SF BAR
SCA...MRY BAY
GLW...SF BAY UNTIL 3 AM
&&
$$
PUBLIC FORECAST: CANEPA/R_WALBRUN
AVIATION: CW
MARINE: BELL/CW
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AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
1010 PM PDT SUN APR 24 2016
.SYNOPSIS...
PARTLY CLOUDY OVERNIGHT WITH SOME INCREASE IN HIGH CLOUDS LATER
TONIGHT...AND TEMPERATURES A LITTLE ABOVE NORMAL. COOLER ON MONDAY
WITH INCREASING CLOUDS...STRONG AND GUSTY WEST WINDS...AND A CHANCE
FOR LIGHT SHOWERS OVER AND WEST OF THE MOUNTAINS. DRY AND A LITTLE
WARMER FOR TUESDAY AND MOST OF WEDNESDAY UNDER WEAK HIGH PRESSURE
ALOFT. SIGNIFICANT COOLING AGAIN FOR LATE WEDNESDAY AND THURSDAY
WITH A CHANCE FOR SHOWERS AND MOUNTAIN SNOW...ALONG WITH GUSTY WEST
WINDS IN THE MOUNTAINS AND DESERTS. THE SHOWERS TAPER OFF ON
FRIDAY...BUT CONDITIONS REMAIN COOL BEFORE WARMING NEXT WEEKEND AS A
RIDGE ALOFT BUILDS.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
...EVENING UPDATE...
WINDS WERE RATHER STRONG DURING THE EARLY EVENING IN THE
DESERTS...BUT HAS SINCE COME INTO A LULL. EXPECT SOME RENEWED STRONG
WINDS OVER THE MOUNTAINS AND INTO THE DESERTS LATE TONIGHT TOWARDS
DAYBREAK.
THE MODELS ARE IN GOOD AGREEMENT THAT PRESSURE GRADIENTS WILL PICK
UP SUBSTANTIALLY ON MONDAY AS A STRONG TROUGH DROPS INTO THE GREAT
BASIN. ALTHOUGH PRECIP CHANCES ARE MEAGER FOR OUR REGION WITH THIS
SYSTEM WITH JUST SOME LIGHT PRECIP POSSIBLE OVER THE
MOUNTAINS...WINDS WILL DEFINITELY BE THE OVERWHELMING CONCERN
THROUGH MONDAY NIGHT. DIURNALLY ENHANCED STRONG WINDS OVER THE COAST
AND INTERIOR VALLEYS MAY BE A SIGNIFICANT IMPACT FOR MONDAY
AFTERNOON RUSH HOUR...WITH WIND GUSTS OF 35 TO 45 MPH LIKELY AT
TIMES...ESPECIALLY IN THE NORTHERN INLAND EMPIRE AND ORANGE COUNTY
WHERE THE GRADIENTS WILL BE MAXIMIZED. STRONG WINDS WILL ALSO BE
NOTED ACROSS ALL OF THE MOUNTAIN AND DESERTS AREAS...PEAKING MONDAY
EVENING...THEN DIMINISHING TOWARDS TUESDAY MORNING.
THE STRONGEST WINDS MAY BE NOTED IN THE SAN BERNARDINO COUNTY
MOUNTAINS AND DESERTS WITH ISOLATED WIND GUSTS OF 60 TO 70 MPH
POSSIBLE IN REMOTE LOCATIONS. WE CONSIDERED ISSUING A HIGH WIND
WARNING BUT AT THIS TIME THE LOCATIONS AND IMPACTS WERE NOT DEEMED
WIDESPREAD ENOUGH TO SUPPORT A WARNING. LATER SHIFTS WILL NEED TO
KEEP A CLOSE EYE ON THE LATEST OBSERVATIONS AND HI-RES GUIDANCE.
...REMAINDER OF PREVIOUS DISCUSSION...ISSUED AT 159 PM PDT...
VISIBLE SATELLITE THIS AFTERNOON SHOWS AREAS OF HIGH CLOUDS
MOVING IN FROM THE WEST. MEANWHILE...TEMPERATURES ARE SEVERAL
DEGREES ABOVE WHAT THEY WERE AT THIS TIME YESTERDAY FOR A MAJORITY
OF THE AREA.
MODELS CONTINUE TO SHOW A LOW MOVING DOWN FROM THE NORTH LATE
WEDNESDAY THROUGH THURSDAY...CREATING A MORE SIGNIFICANT COOL-
DOWN...INCREASING CLOUDS...GUSTY WINDS IN THE MOUNTAINS AND DESERTS
AND POTENTIALLY PRODUCING PERIODS OF LIGHT TO MODERATE SHOWERS. THE
ENSEMBLES REMAIN IN FAIRLY GOOD AGREEMENT...ALTHOUGH THE ECMWF IS A
LITTLE WETTER AND ALSO QUICKER WITH BRINGING THE TROUGH INTO THE
REGION. MOST MODEL SOLUTIONS BRING THE COLD CORE OF THE LOW CLOSE
TO...OR OVER...SOUTHERN CALIFORNIA...SO SOME LOCALLY HEAVIER SHOWERS
AND/OR THUNDERSTORMS ARE A POSSIBILITY.
SNOW LEVELS LOWER TO AROUND 6500-7500 FEET WITH A FEW INCHES OF SNOW
POSSIBLE ABOVE THAT ELEVATION.
THERE MAY BE A FEW LINGERING SHOWERS FRIDAY AS THE TROUGH SLOWLY
MOVES EAST. 12Z GFS AND 12Z ECMWF ARE NOW IN MUCH BETTER ALIGNMENT
FOR THE FORECAST FOR NEXT WEEKEND...AS THEY BOTH INDICATE RIDGING
BUILDING IN FROM THE WEST...WHICH WOULD RESULT IN DRY CONDITIONS
AND WARMING.
&&
.AVIATION...
250400...COAST/VALLEYS...BKN015-025 WITH TOPS TO 5000 FT MSL THROUGH
10Z. AFTER 10Z THE CLOUDS WILL SCATTER OUT FROM THE COAST, FOLLOWED
BY CLEARING IN THE INLAND AREAS AND COASTAL SLOPES LATER IN THE
MORNING. BECOMING WINDY. WEST WINDS INCREASING TO 15-20 KT AFTER 16Z
WITH GUSTS 25-30 KT.
MOUNTAINS/DESERTS...WINDY. NORTHWEST WINDS 20-30 KT GUSTING TO 50-60
WITH LLWS AND STRONG UDDFS. SURFACING MOUNTAIN WAVES AND ROTORS OVER
THE DESERTS THROUGH TUESDAY MORNING IMPACTING PSP AND TRM. PARTIAL
MTN OBSCURATION THROUGH 18Z MONDAY.
&&
.MARINE...
900 PM...SAN CLEMENTE BASIN BUOY REPORTED WEST WINDS 17G23KT SUNDAY
EVENING. THE STRONG NORTHWEST WINDS WILL CONTINUE THROUGH MONDAY
NIGHT WITH SUSTAINED WINDS OF 15-30 KT AND GUSTS 35 TO 40 KT.
STRONGEST GALES WILL OCCUR OVER THE OUTER WATERS.
THE WINDS WILL BE ACCOMPANIED BY A 9-12 FT NORTHWEST SWELL AT 10-13
SECONDS FROM 290 DEGREES. THE WINDS AND SWELL WILL PRODUCE COMBINED
SEAS OF 9-14 FT. HIGHEST WINDS AND SEAS WILL OCCUR NEAR AND SOUTH OF
SAN CLEMENTE ISLAND.
&&
.BEACHES...
900 PM...A 10-12 FT NW SWELL WILL PEAK MONDAY AND TUESDAY AND BRING
ELEVATED SURF AND STRONG RIP CURRENTS TO THE BEACHES THROUGH
TUESDAY. SURF WILL BE 3-6 FT SURF AT MOST BEACHES WITH SETS TO 7 FT
POSSIBLE IN SOUTHERN SAN DIEGO COUNTY.
&&
.SKYWARN...
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...WIND ADVISORY FROM 5 PM THIS AFTERNOON TO 11 PM PDT MONDAY 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.
WIND ADVISORY FROM NOON TO 9 PM PDT MONDAY FOR ORANGE COUNTY
COASTAL AREAS-ORANGE COUNTY INLAND AREAS-SAN BERNARDINO AND
RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-SAN DIEGO COUNTY
COASTAL AREAS-SAN DIEGO COUNTY VALLEYS-SANTA ANA MOUNTAINS
AND FOOTHILLS.
BEACH HAZARDS STATEMENT THROUGH TUESDAY EVENING FOR ORANGE
COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS.
PZ...SMALL CRAFT ADVISORY UNTIL 8 PM PDT THIS EVENING 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.
GALE WARNING FROM 8 PM THIS EVENING TO 11 PM PDT MONDAY 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...HARRISON/BROTHERTON
AVIATION/MARINE/BEACHES...MOEDE
[top]
Area Forecast Discussion
National Weather Service Sacramento CA
953 PM PDT SUN APR 24 2016
.Synopsis...
Unsettled and cool weather Sunday and Monday, then again Tuesday
night and Wednesday.
&&
.Discussion...
Cluster of strong thunderstorms developed around Maxwell this
afternoon and moved ESEwd...interacting with the Delta Breeze
E of SAC...and forming a line of storms from around Granite Bay Swd
to Rancho Seco. This line moved E into the Motherlode. As the
cluster of storms neared or intersected with the Delta Breeze
between Rocklin/Granite Bay...radar indicated a potential rotating
head configuration but with very weak circulation...and did not
receive reports of any rotating storms there. Activity is finally
windind down with lingering showers and isolated over zone 69 S of
I-80.
The center of the trough will be over Central Nevada on Monday and
may bring some wrap around moisture and showers to the Sierra
Nevada. Snow levels look to be around 7000 feet during the day.
Most other areas should remain dry, cool with breezy to locally
windy northerly winds for the valley. The strongest winds look
like they should be over the west side of the valley. Nly pressure
gradients have increased to 8 mbs or so...a little stronger than
forecast...so the models may be slightly understanding the strength
of the Nly gradients initially. Wind advisory may be needed on Mon
for the Valley given the gradients...925 mbs winds and forecast
strength of the subsidence in the wake of the vort max moving
through the Nly flow in the wake of the Central NV upper low.
Tuesday will be dry and warmer as a ridge builds over the area
with lighter northerly flow. The dry weather looks short lived as
another system moves into the region Tuesday night and Wednesday.
Wednesday`s system should bring a little bit more precipitation to
the region with the best chances continuing over the foothills and
mountains. Have left out any mention of thunderstorms for now but
at this point perhaps a low probability for some on Wednesday
looks possible. Several inches of snow also looks possible near
pass levels. /JHM
.EXTENDED DISCUSSION (Thursday THROUGH Sunday)
Upper low continues to dig southward into SoCal Thursday
maintaining a slight chance of wrap around showers over the
eastern foothills and mountains...from near Lassen Park southward.
Drier with warming temperatures and locally breezy North to East
wind Friday into the weekend as upper ridging builds over NorCal.
&&
.AVIATION...
General VFR conditions tonight except for local MVFR/IFR lingering
showers and evening thunderstorms over the mountains and
foothills...snow showers possible above 5000 feet. Areas of
northerly surface winds gusting 20 to 30 kt through 18z with LLWS
possible in the Valley overnight. Winds may gust up to 35-40kt
Monday afternoon. EK
&&
.STO Watches/Warnings/Advisories...
None.
&&
$$
[top]
Area Forecast Discussion...UPDATED
National Weather Service Reno NV
912 PM PDT SUN APR 24 2016
.UPDATE...
Latest radar/satellite imagery and surface reports indicate light
scattered rain/snow showers across the region with thunderstorms
remaining isolated due to the lack of surface heating and only
weak large scale forcing. Colder air was advecting into far
northeast CA and northwest NV where temperatures had fallen into
the 30s. So precipitation in these areas is likely switching over
to snow. The 00z GFS continues to show a band forming across
northwest NV this evening and then shifting east and south Monday
morning while the NAM/latest HRRR are much lighter with the QPF.
While latest radar trends make confidence of the GFS scenario a
bit lower, there is still time for this band to form based on
current track of upper low. So we will continue the snow advisory
for Surprise Valley and northwest NV.
As the band works southeast, light rain and mountain snow will
continue across the basin and range into Monday morning, possibly
extending back into the Reno-Carson City area. We are not
anticipating any commute issues for the I-80/Hwy 50 corridors as
valley temperatures will be a bit too warm. The gradient will
tighten overnight and brisk northwest winds are expected across
the area for Monday. Also, latest model projections show the
airmass stabilizing along and north of I-80 during the afternoon.
So showers may be mostly south and east of Reno-Lovelock in the
afternoon. Hohmann
&&
.PREVIOUS DISCUSSION... /Issued 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 until 8 AM PDT Monday NVZ005.
CA...Winter Weather Advisory until 8 AM PDT Monday CAZ070.
&&
$$
For more information from the National Weather Service visit...
http://weather.gov/reno
AREA FORECAST DISCUSSION...UPDATED
NWS TAMPA BAY RUSKIN FL
355 AM EDT MON APR 25 2016
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A COMPLEX UPPER LEVEL
PATTERN OVER NORTH AMERICA THIS MORNING. THE MAIN FEATURE OF NOTE
INCLUDE A DEEP/SHARP TROUGH MOVING ASHORE OVER THE PACIFIC
COAST...WHICH THEN TRANSLATES INTO A POTENT UPPER LEVEL CLOSED LOW
SPINNING OVER THE HIGH PLAINS. THIS UPPER LOW IS SUPPORTING NUMEROUS
CLUSTER OF STRONG THUNDERSTORMS FROM THE CENTRAL PLAINS TO THE UPPER
MIDWEST. THE OTHER FEATURE OF NOTE...AND THE MOST IMPORTANT TO OUR
FORECAST THE NEXT 24 HOURS IS A SOUTHERN STREAM SHORTWAVE FEATURE
STEADILY PROGRESSING EASTWARD ACROSS THE GULF OF MEXICO TOWARD THE
FLORIDA PENINSULA. THIS ENERGY WILL HAVE SOME IMPACT ON OUR FORECAST
FOR LATER THIS AFTERNOON/EVENING...AND WE WILL DISCUSS THIS FEATURE
IN MORE DETAIL IN THE SHORT TERM DISCUSSION BELOW.
AT THE SURFACE...A LARGE SPRAWLING RIDGE OF HIGH PRESSURE IS LOCATED
ALONG THE EASTERN SEABOARD. THIS HIGH RIDGES ALL THE WAY SOUTH TO
COVER THE ENTIRE FLORIDA PENINSULA AND EASTERN GULF OF MEXICO. AS A
RESULT...THE GRADIENT IS FAIRLY RELAXED ACROSS THE REGION. THE WEAK
LOW LEVEL FLOW AND STRONG TERRESTRIAL HEATING WILL PROMOTE THE
DEVELOPMENT OF A HEALTHY SEA-BREEZE THIS AFTERNOON/EARLY EVENING.
&&
.SHORT TERM (TODAY THROUGH TUESDAY)...
AS MENTIONED ABOVE...WATCHING THE PROGRESS OF A WELL-DEFINED
SOUTHERN STREAM SHORTWAVE APPROACHING OVER THE GULF OF MEXICO. THE
MAIN SYNOPTIC FORCING/QVECTOR CONVERGENCE AHEAD OF THE TROUGH
AXIS ACTUALLY PASSES THROUGH OUR REGION AND OFF INTO THE ATLANTIC
FAIRLY EARLY TODAY. HOWEVER...WEAK HEIGHT FALLS CONTINUE INTO THE
AFTERNOON HOURS WITH MID-LEVEL LAPSE RATES IMPROVING/INCREASING TO
6-6.5C/KM. GIVEN THE LOWERED HEIGHT AND CERTAINLY LESS LARGE SCALE
SUPPRESSION THAN WAS SEEN ON SUNDAY...COMBINED WITH AN
INCREASINGLY FAVORABLE MOISTURE PROFILE...ANTICIPATE A MORE ACTIVE
CONVECTIVE SCENARIO THAN THE ISOLATED SHOWERS THAT FORMED ALONG
THE SEA-BREEZE LATE SUNDAY. SIMILAR TO SUNDAY...ANY
SHOWERS/ISOLATED STORMS WILL HOLD OFF UNTIL LATE IN THE
AFTERNOON...MEANING MOST OF THE DAYLIGHT HOURS TODAY WILL BE DRY.
TEMPERATURES CLIMB INTO THE 80S...AND WELL INTO THE 80S AWAY FROM
THE BEACHES. ONCE AGAIN...A WELL-DEFINED SEABREEZE CIRCULATION
WILL BECOMES ESTABLISHED BY 17-18Z. ONCE THE SEABREEZE BEGINS TO
PUSH INLAND...LOW LEVEL FOCUS AHEAD OF THE BOUNDARY WILL
COMPLIMENT THE IMPROVING THERMODYNAMICS ALOFT TO ALLOW A
SCATTERING OF SHOWERS TO DEVELOP ALONG THE I-75 CORRIDOR. GIVEN
THE FLOW PATTERN...MUCH IF NOT ALL THE CONVECTION WILL BE FOCUSED
ALONG THE FLORIDA WEST COAST BY LATE AFTERNOON. FOR NOW...WILL
KEEP RAIN CHANCES ALONG THIS CORRIDOR IN THE 30-50% RANGE AFTER
20Z...HOWEVER...NEIGHBORHOOD ENSEMBLE POPS FROM THE CONVECTION
ALLOWING GUIDANCE SUITE ARE ACTUALLY MORE AGGRESSIVE. SINCE
CONVECTION ALLOWING MODELS ARE OFTEN TOO AGGRESSIVE WITH
CONVECTION...ESPECIALLY THIS TIME OF YEAR...THE 30-50% POPS SEEM
A REASONABLE APPROACH. GIVEN THE MORE UNIFORM THERMODYNAMIC
ENVIRONMENT ACROSS THE AREA...WILL EXPECT SCT CONVECTION TO FIRE ALL
THE WAY UP THROUGH THE NATURE COAST TODAY AS WELL. FCST SOUNDING
PROFILES SUGGEST AN EQUILIBRIUM LEVEL AROUND 30,000 FEET AGL LATER
THIS AFTERNOON...PROVIDING A MUCH BETTER OPPORTUNITY TODAY FOR
UPDRAFTS TO REACH HEIGHTS CONDUCIVE FOR CHARGE SEPARATION AND
LIGHTING POTENTIAL. ALSO...THE COOLER MID-LEVEL TEMPS (-12C AT 500MB
FOR EXAMPLE) ALLOWS FOR DECENT CAPE PROFILES THROUGH THE -10C TO
-30C HAIL GROWTH ZONE... PER LATEST NAM/ARW/HRRR BUFKIT SOUNDINGS.
ANY STORMS THAT CAN SUPPORT A STRONGER AND/OR LONGER LASTING UPDRAFT
WILL HAVE THE POTENTIAL FOR SMALL HAIL. THE SCT CONVECTION WILL BE
SLOW MOVING TODAY...BUT SHOULD GENERALLY MIGRATE TOWARD THE COAST
AND OFFSHORE DURING THE EARLY/MID EVENING HOURS...BEFORE DISSIPATING.
THE SHORTWAVE AXIS MAKES A QUICK EXIT TO OUR EAST AND SOUTHEAST
TONIGHT...ALLOWING SUBTLE HEIGHT RISES OVER THE FLORIDA PENINSULA BY
SUNRISE TUESDAY. THIS PROCESS WILL CONTINUE THROUGHOUT TUESDAY AND
RESULT IN WELL DEFINED MID/UPPER RIDGING OVER OUR HEADS BY THE
SECOND HALF OF THE DAY. NEAR THE SURFACE...RIDGING WILL REMAIN IN
CONTROL FROM A HIGH CENTER LOCATED OVER THE WESTERN ATLANTIC. STRONG
TERRESTRIAL HEATING AND WEAK LOW LEVEL FLOW AGAIN ALLOWS SEA-
BREEZE FORMATION TO TURN WINDS ONSHORE AT THE BEACHES AFTER 17Z.
A SIMILAR FLOW PATTERN IN THE LOWER LEVELS TO PREVIOUS DAYS WILL
KEEP THE BEST CONVERGENCE ACROSS THE WESTERN SIDE OF THE FL
PENINSULA. CERTAINLY THE UPPER LEVELS THERMODYNAMICS ARE LESS
FAVORABLE BY TUESDAY AFTERNOON...AS THE RIDGING CONTINUES TO
BUILD...AND THEREFORE WILL SWING THE FORECAST BACK THE OTHER WAY
TOWARD MORE ISOLATED AND SHALLOW CONVECTION LATE TUESDAY
AFTERNOON/EVENING. HIGH TEMPERATURES TUESDAY IN THE MID/UPPER 80S
AWAY FROM THE BEACHES AND LOWER 80S AT THE IMMEDIATE COAST.
&&
.MID/LONG TERM (WEDNESDAY THROUGH NEXT SUNDAY)...
THE MID AND LONG TERM FORECAST PERIODS WILL FEATURE DRY WEATHER
AND ABOVE NORMAL TEMPERATURES FOR WEST CENTRAL AND SW FLORIDA.
SURFACE HIGH PRESSURE WILL REMAIN IN PLACE ACROSS THE WESTERN
ATLANTIC LEAVING US IN A PREDOMINANT E TO SE LOW-LEVEL FLOW FOR
MUCH OF THE WEEK AND INTO NEXT WEEKEND. THE ATMOSPHERE WILL REMAIN
FAIRLY DRY IN THE MID TO UPPER LEVELS AS MOST OF THE AVAILABLE
ATMOSPHERIC MOISTURE WILL REMAIN BELOW THE 700 MB LEVEL. THIS WILL
MAKE THE ENVIRONMENT VERY HOSTILE TO ANY SHOWERS THAT TRY TO
DEVELOP DURING THE AFTERNOON HOURS. ITS POSSIBLE THAT MAYBE A
STRAY SHOWER COULD DEVELOP WITH SEABREEZE INTERACTIONS BUT GIVEN
THE HOSTILE MID/UPPER LEVELS THEY WOULD BE FAIRLY SHALLOW SHOWERS
AND QPF WOULD BE VERY LOW. THAT BEING SAID MOST OF THE AREA CAN
EXPECT TO REMAIN DRY THIS WEEK AND INTO NEXT WEEKEND AND WILL KEEP
POPS BELOW 20 PERCENT AREA WIDE THROUGH THE FORECAST PERIOD.
DAILY AFTERNOON TEMPERATURES ARE EXPECTED TO TOP OUT IN THE MID TO
UPPER 80S...WITH SOME SPOTS REACHING 90 NOT OUT OF THE QUESTION
ACROSS THE INTERIOR. DAILY SEABREEZE DEVELOPMENT IN THE EARLY
AFTERNOON WILL HELP KEEP THE COASTAL REGIONS A TAD COOLER. OVERNIGHT
LOWS WILL BE ON THE MILD SIDE WITH MID TO UPPER 60S EXPECTED...LOWER
70S LIKELY NEAR THE IMMEDIATE COAST.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS WEST-CENTRAL AND SOUTHWEST FLORIDA
EARLY THIS MORNING. LOW POTENTIAL FOR A BRIEF PERIOD OF MVFR MIST
AT KLAL/KPGD AROUND DAWN...BUT OTHERWISE ANTICIPATE THE VFR
CONDITIONS TO PERSIST THROUGH THE MORNING HOURS. SCT SHOWERS AND
EVEN A FEW THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE SEA
BREEZE LATE THIS AFTERNOON (MAINLY AFTER 19-20Z) INTO THE EVENING
HOURS. ANY TERMINAL MAY SEE A BRIEF RESTRICTIONS ASSOCIATED WITH A
PASSING SHOWERS. SHOWERS DISSIPATE AFTER SUNSET.
&&
.MARINE...
THE PATTERN REMAINS STAGNANT THROUGH THE MIDDLE PORTION OF THE
WEEK...WITH HIGH PRESSURE OFF THE EASTERN SEABOARD CONTINUES TO
RIDGE BACK TO THE WEST OVER THE FLORIDA PENINSULA AND EASTERN GULF
OF MEXICO. THE PREDOMINANT LARGE SCALE FLOW AROUND THIS RIDGE
WILL BE FROM THE SOUTHEAST...HOWEVER THE GRADIENT IS WEAK ENOUGH
TO ALLOW WINDS TO TURN ONSHORE NEAR THE COAST EACH AFTERNOON AND
EVENING...BEFORE SWITCHING BACK TO THE SOUTHEAST BY MIDNIGHT EACH
NIGHT. WINDS AND SEAS WILL GENERALLY REMAIN BELOW HEADLINE
CRITERIA FOR SEVERAL DAYS TO COME. MARINERS SHOULD KEEP AN EYE TO
THE EAST LATER THIS AFTERNOON AS SCATTERED THUNDERSTORM ARE
EXPECTED TO DEVELOP ALONG THE I-75 CORRIDOR AFTER 3-4 PM EDT...AND
THEN SLOWLY MIGRATE OFFSHORE THROUGH THE EARLY EVENING HOURS.
STORMS WILL BE MUCH MORE ISOLATED IN NATURE FOR LATER TUESDAY AND
WEDNESDAY.
&&
.FIRE WEATHER...
HIGH PRESSURE AT THE SURFACE CONTINUE TO RIDGE OVER THE REGION FROM
THE WESTERN ATLANTIC THROUGH THE NEXT SEVERAL DAYS. SCATTERED STORMS
ARE ANTICIPATED TO DEVELOP ALONG THE I-75 CORRIDOR LATE THIS
AFTERNOON INTO THE EVENING HOUR BEFORE DISSIPATING AFTER SUNSET.
ONLY ISOLATED SHOWERS ARE EXPECTED LATE TUESDAY AND LATE WEDNESDAY
AFTERNOONS. RELATIVE HUMIDITY VALUES GENERALLY REMAIN ABOVE CRITICAL
LEVELS THROUGH THURSDAY. A FEW SPOTS MAY BRIEFLY REACH 35 PERCENT
ANY AFTERNOON...HOWEVER...EXTENDED DURATIONS OF CRITICAL RH ARE
UNLIKELY...AND WINDS WILL REMAIN BELOW CRITICAL LEVELS.
THEREFORE...NO RED FLAG CONDITIONS ARE ANTICIPATED THE NEXT SEVERAL
DAYS.
FOG POTENTIAL...ISOLATED POCKETS OF FOG ARE POSSIBLE INLAND EACH
NIGHT THROUGH THURSDAY...HOWEVER NO SIGNIFICANT AREAS OF DENSE FOG
OR VISIBILITY REDUCTIONS ARE ANTICIPATED.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 85 69 86 69 / 50 50 20 10
FMY 86 67 85 67 / 50 50 20 10
GIF 85 66 87 66 / 30 20 20 10
SRQ 80 69 81 67 / 30 30 10 10
BKV 86 64 84 63 / 40 40 20 10
SPG 84 70 84 71 / 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...CORRECTED
NWS TAMPA BAY RUSKIN FL
340 AM EDT MON APR 25 2016
.SYNOPSIS...
07Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A COMPLEX UPPER LEVEL
PATTERN OVER NORTH AMERICA THIS MORNING. THE MAIN FEATURE OF NOTE
INCLUDE A DEEP/SHARP TROUGH MOVING ASHORE OVER THE PACIFIC
COAST...WHICH THEN TRANSLATES INTO A POTENT UPPER LEVEL CLOSED LOW
SPINNING OVER THE HIGH PLAINS. THIS UPPER LOW IS SUPPORTING
NUMEROUS CLUSTER OF STRONG THUNDERSTORMS FROM THE CENTRAL PLAINS
TO THE UPPER MIDWEST. THE OTHER FEATURE OF NOTE...AND THE MOST
IMPORTANT TO OUR FORECAST THE NEXT 24 HOURS IS A SOUTHERN STREAM
SHORTWAVE FEATURE STEADILY PROGRESSING EASTWARD ACROSS THE GULF OF
MEXICO TOWARD THE FLORIDA PENINSULA. THIS ENERGY WILL HAVE SOME
IMPACT ON OUR FORECAST FOR LATER THIS AFTERNOON/EVENING...AND WE
WILL DISCUSS THIS FEATURE IN MORE DETAIL IN THE SHORT TERM
DISCUSSION BELOW.
AT THE SURFACE...A LARGE SPRAWLING RIDGE OF HIGH PRESSURE IS LOCATED
ALONG THE EASTERN SEABOARD. THIS HIGH RIDGES ALL THE WAY SOUTH TO
COVER THE ENTIRE FLORIDA PENINSULA AND EASTERN GULF OF MEXICO. AS A
RESULT...THE GRADIENT IS FAIRLY RELAXED ACROSS THE REGION. THE WEAK
LOW LEVEL FLOW AND STRONG TERRESTRIAL HEATING WILL PROMOTE THE
DEVELOPMENT OF A HEALTHY SEA-BREEZE THIS AFTERNOON/EARLY EVENING.
&&
.SHORT TERM (TODAY THROUGH TUESDAY)...
AS MENTIONED ABOVE...WATCHING THE PROGRESS OF A WELL-DEFINED
SOUTHERN STREAM SHORTWAVE APPROACHING OVER THE GULF OF MEXICO. THE
MAIN SYNOPTIC FORCING/QVECTOR CONVERGENCE AHEAD OF THE TROUGH
AXIS ACTUALLY PASSES THROUGH OUR REGION AND OFF INTO THE ATLANTIC
FAIRLY EARLY TODAY. HOWEVER...WEAK HEIGHT FALLS CONTINUE INTO THE
AFTERNOON HOURS WITH MID-LEVEL LAPSE RATES IMPROVING/INCREASING TO
6-6.5C/KM. GIVEN THE LOWERED HEIGHT AND CERTAINLY LESS LARGE SCALE
SUPPRESSION THAN WAS SEEN ON SUNDAY...COMBINED WITH AN
INCREASINGLY FAVORABLE MOISTURE PROFILE...ANTICIPATE A MORE ACTIVE
CONVECTIVE SCENARIO THAN THE ISOLATED SHOWERS THAT FORMED ALONG
THE SEA-BREEZE LATE SUNDAY. SIMILAR TO SUNDAY...ANY
SHOWERS/ISOLATED STORMS WILL HOLD OFF UNTIL LATE IN THE
AFTERNOON...MEANING MOST OF THE DAYLIGHT HOURS TODAY WILL BE DRY.
TEMPERATURES CLIMB INTO THE 80S...AND WELL INTO THE 80S AWAY FROM
THE BEACHES. ONCE AGAIN...A WELL-DEFINED SEABREEZE CIRCULATION
WILL BECOMES ESTABLISHED BY 17-18Z. ONCE THE SEABREEZE BEGINS TO
PUSH INLAND...LOW LEVEL FOCUS AHEAD OF THE BOUNDARY WILL
COMPLIMENT THE IMPROVING THERMODYNAMICS ALOFT TO ALLOW A
SCATTERING OF SHOWERS TO DEVELOP ALONG THE I-75 CORRIDOR. GIVEN
THE FLOW PATTERN...MUCH IF NOT ALL THE CONVECTION WILL BE FOCUSED
ALONG THE FLORIDA WEST COAST BY LATE AFTERNOON. FOR NOW...WILL
KEEP RAIN CHANCES ALONG THIS CORRIDOR IN THE 30-50% RANGE AFTER
20Z...HOWEVER...NEIGHBORHOOD ENSEMBLE POPS FROM THE CONVECTION
ALLOWING GUIDANCE SUITE ARE ACTUALLY MORE AGGRESSIVE. SINCE
CONVECTION ALLOWING MODELS ARE OFTEN TOO AGGRESSIVE WITH
CONVECTION...ESPECIALLY THIS TIME OF YEAR...THE 30-50% POPS SEEM
A REASONABLE APPROACH. GIVEN THE MORE UNIFORM THERMODYNAMIC
ENVIRONMENT...WILL EXPECT SOME CONVECTION TO FIRE ALL THE WAY UP
THROUGH THE NATURE COAST TODAY AS WELL. THERE IS A BETTER CHANCE
TODAY THAT UPDRAFTS REACH HEIGHTS CONDUCIVE FOR CHARGE SEPARATION
AND LIGHTING POTENTIAL. THE SCT CONVECTION WILL BE SLOW MOVING
TODAY...BUT SHOULD GENERALLY MIGRATE TOWARD THE COAST AND OFFSHORE
DURING THE EARLY/MID EVENING HOURS...BEFORE DISSIPATING.
THE SHORTWAVE AXIS MAKES A QUICK EXIT TO OUR EAST AND SOUTHEAST
TONIGHT...ALLOWING SUBTLE HEIGHT RISES OVER THE FLORIDA PENINSULA BY
SUNRISE TUESDAY. THIS PROCESS WILL CONTINUE THROUGHOUT TUESDAY AND
RESULT IN WELL DEFINED MID/UPPER RIDGING OVER OUR HEADS BY THE
SECOND HALF OF THE DAY. NEAR THE SURFACE...RIDGING WILL REMAIN IN
CONTROL FROM A HIGH CENTER LOCATED OVER THE WESTERN ATLANTIC. STRONG
TERRESTRIAL HEATING AND WEAK LOW LEVEL FLOW AGAIN ALLOWS SEA-
BREEZE FORMATION TO TURN WINDS ONSHORE AT THE BEACHES AFTER 17Z.
A SIMILAR FLOW PATTERN IN THE LOWER LEVELS TO PREVIOUS DAYS WILL
KEEP THE BEST CONVERGENCE ACROSS THE WESTERN SIDE OF THE FL
PENINSULA. CERTAINLY THE UPPER LEVELS THERMODYNAMICS ARE LESS
FAVORABLE BY TUESDAY AFTERNOON...AS THE RIDGING CONTINUES TO
BUILD...AND THEREFORE WILL SWING THE FORECAST BACK THE OTHER WAY
TOWARD MORE ISOLATED AND SHALLOW CONVECTION LATE TUESDAY
AFTERNOON/EVENING. HIGH TEMPERATURES TUESDAY IN THE MID/UPPER 80S
AWAY FROM THE BEACHES AND LOWER 80S AT THE IMMEDIATE COAST.
&&
.MID/LONG TERM (WEDNESDAY THROUGH NEXT SUNDAY)...
THE MID AND LONG TERM FORECAST PERIODS WILL FEATURE DRY WEATHER
AND ABOVE NORMAL TEMPERATURES FOR WEST CENTRAL AND SW FLORIDA.
SURFACE HIGH PRESSURE WILL REMAIN IN PLACE ACROSS THE WESTERN
ATLANTIC LEAVING US IN A PREDOMINANT E TO SE LOW-LEVEL FLOW FOR
MUCH OF THE WEEK AND INTO NEXT WEEKEND. THE ATMOSPHERE WILL REMAIN
FAIRLY DRY IN THE MID TO UPPER LEVELS AS MOST OF THE AVAILABLE
ATMOSPHERIC MOISTURE WILL REMAIN BELOW THE 700 MB LEVEL. THIS WILL
MAKE THE ENVIRONMENT VERY HOSTILE TO ANY SHOWERS THAT TRY TO
DEVELOP DURING THE AFTERNOON HOURS. ITS POSSIBLE THAT MAYBE A
STRAY SHOWER COULD DEVELOP WITH SEABREEZE INTERACTIONS BUT GIVEN
THE HOSTILE MID/UPPER LEVELS THEY WOULD BE FAIRLY SHALLOW SHOWERS
AND QPF WOULD BE VERY LOW. THAT BEING SAID MOST OF THE AREA CAN
EXPECT TO REMAIN DRY THIS WEEK AND INTO NEXT WEEKEND AND WILL KEEP
POPS BELOW 20 PERCENT AREA WIDE THROUGH THE FORECAST PERIOD.
DAILY AFTERNOON TEMPERATURES ARE EXPECTED TO TOP OUT IN THE MID TO
UPPER 80S...WITH SOME SPOTS REACHING 90 NOT OUT OF THE QUESTION
ACROSS THE INTERIOR. DAILY SEABREEZE DEVELOPMENT IN THE EARLY
AFTERNOON WILL HELP KEEP THE COASTAL REGIONS A TAD COOLER. OVERNIGHT
LOWS WILL BE ON THE MILD SIDE WITH MID TO UPPER 60S EXPECTED...LOWER
70S LIKELY NEAR THE IMMEDIATE COAST.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS WEST-CENTRAL AND SOUTHWEST FLORIDA
EARLY THIS MORNING. LOW POTENTIAL FOR A BRIEF PERIOD OF MVFR MIST
AT KLAL/KPGD AROUND DAWN...BUT OTHERWISE ANTICIPATE THE VFR
CONDITIONS TO PERSIST THROUGH THE MORNING HOURS. SCT SHOWERS AND
EVEN A FEW THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE SEA
BREEZE LATE THIS AFTERNOON (MAINLY AFTER 19-20Z) INTO THE EVENING
HOURS. ANY TERMINAL MAY SEE A BRIEF RESTRICTIONS ASSOCIATED WITH A
PASSING SHOWERS. SHOWERS DISSIPATE AFTER SUNSET.
&&
.MARINE...
THE PATTERN REMAINS STAGNANT THROUGH THE MIDDLE PORTION OF THE
WEEK...WITH HIGH PRESSURE OFF THE EASTERN SEABOARD CONTINUES TO
RIDGE BACK TO THE WEST OVER THE FLORIDA PENINSULA AND EASTERN GULF
OF MEXICO. THE PREDOMINANT LARGE SCALE FLOW AROUND THIS RIDGE
WILL BE FROM THE SOUTHEAST...HOWEVER THE GRADIENT IS WEAK ENOUGH
TO ALLOW WINDS TO TURN ONSHORE NEAR THE COAST EACH AFTERNOON AND
EVENING...BEFORE SWITCHING BACK TO THE SOUTHEAST BY MIDNIGHT EACH
NIGHT. WINDS AND SEAS WILL GENERALLY REMAIN BELOW HEADLINE
CRITERIA FOR SEVERAL DAYS TO COME. MARINERS SHOULD KEEP AN EYE TO
THE EAST LATER THIS AFTERNOON AS SCATTERED THUNDERSTORM ARE
EXPECTED TO DEVELOP ALONG THE I-75 CORRIDOR AFTER 3-4 PM EDT...AND
THEN SLOWLY MIGRATE OFFSHORE THROUGH THE EARLY EVENING HOURS.
STORMS WILL BE MUCH MORE ISOLATED IN NATURE FOR LATER TUESDAY AND
WEDNESDAY.
&&
.FIRE WEATHER...
HIGH PRESSURE AT THE SURFACE CONTINUE TO RIDGE OVER THE REGION FROM
THE WESTERN ATLANTIC THROUGH THE NEXT SEVERAL DAYS. SCATTERED STORMS
ARE ANTICIPATED TO DEVELOP ALONG THE I-75 CORRIDOR LATE THIS
AFTERNOON INTO THE EVENING HOUR BEFORE DISSIPATING AFTER SUNSET.
ONLY ISOLATED SHOWERS ARE EXPECTED LATE TUESDAY AND LATE WEDNESDAY
AFTERNOONS. RELATIVE HUMIDITY VALUES GENERALLY REMAIN ABOVE CRITICAL
LEVELS THROUGH THURSDAY. A FEW SPOTS MAY BRIEFLY REACH 35 PERCENT
ANY AFTERNOON...HOWEVER...EXTENDED DURATIONS OF CRITICAL RH ARE
UNLIKELY...AND WINDS WILL REMAIN BELOW CRITICAL LEVELS.
THEREFORE...NO RED FLAG CONDITIONS ARE ANTICIPATED THE NEXT SEVERAL
DAYS.
FOG POTENTIAL...ISOLATED POCKETS OF FOG ARE POSSIBLE INLAND EACH
NIGHT THROUGH THURSDAY...HOWEVER NO SIGNIFICANT AREAS OF DENSE FOG
OR VISIBILITY REDUCTIONS ARE ANTICIPATED.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 85 69 86 69 / 50 50 20 10
FMY 86 67 85 67 / 50 50 20 10
GIF 85 66 87 66 / 30 20 20 10
SRQ 80 69 81 67 / 30 30 10 10
BKV 86 64 84 63 / 40 40 20 10
SPG 84 70 84 71 / 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 TAMPA BAY RUSKIN FL
330 AM EDT MON APR 25 2016
.SYNOPSIS...
07Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A COMPLEX UPPER LEVEL
PATTERN OVER NORTH AMERICA THIS MORNING. THE MAIN FEATURE OF NOTE
INCLUDE A DEEP/SHARP TROUGH MOVING ASHORE OVER THE PACIFIC
COAST...WHICH THEN TRANSLATES INTO A POTENT UPPER LEVEL CLOSED LOW
SPINNING OVER THE HIGH PLAINS. THIS UPPER LOW IS SUPPORTING
NUMEROUS CLUSTER OF STRONG THUNDERSTORMS FROM THE CENTRAL PLAINS
TO THE UPPER MIDWEST. THE OTHER FEATURE OF NOTE...AND THE MOST
IMPORTANT TO OUR FORECAST THE NEXT 24 HOURS IS A SOUTHERN STREAM
SHORTWAVE FEATURE STEADILY PROGRESSING EASTWARD ACROSS THE GULF OF
MEXICO TOWARD THE FLORIDA PENINSULA. THIS ENERGY WILL HAVE SOME
IMPACT ON OUR FORECAST FOR LATER THIS AFTERNOON/EVENING...AND WE
WILL DISCUSS THIS FEATURE IN MORE DETAIL IN THE SHORT TERM
DISCUSSION BELOW.
AT THE SURFACE...A LARGE SPRAWLING RIDGE OF HIGH PRESSURE IS LOCATED
ALONG THE EASTERN SEABOARD. THIS HIGH RIDGES ALL THE WAY SOUTH TO
COVER THE ENTIRE FLORIDA PENINSULA AND EASTERN GULF OF MEXICO. AS A
RESULT...THE GRADIENT IS FAIRLY RELAXED ACROSS THE REGION. THE WEAK
LOW LEVEL FLOW AND STRONG TERRESTRIAL HEATING WILL PROMOTE THE
DEVELOPMENT OF A HEALTHY SEA-BREEZE THIS AFTERNOON/EARLY EVENING.
&&
.SHORT TERM (TODAY THROUGH TUESDAY)...
AS MENTIONED ABOVE...WATCHING THE PROGRESS OF A WELL-DEFINED
SOUTHERN STREAM SHORTWAVE APPROACHING OVER THE GULF OF MEXICO. THE
MAIN SYNOPTIC FORCING/QVECTOR CONVERGENCE AHEAD OF THE TROUGH
AXIS ACTUALLY PASSES THROUGH OUR REGION AND OFF INTO THE ATLANTIC
FAIRLY EARLY TODAY. HOWEVER...WEAK HEIGHT FALLS CONTINUE INTO THE
AFTERNOON HOURS WITH MID-LEVEL LAPSE RATES IMPROVING/INCREASING TO
6-6.5C/KM. GIVEN THE LOWERED HEIGHT AND CERTAINLY LESS LARGE SCALE
SUPPRESSION THAN WAS SEEN ON SUNDAY...COMBINED WITH AN
INCREASINGLY FAVORABLE MOISTURE PROFILE...ANTICIPATE A MORE ACTIVE
CONVECTIVE SCENARIO THAN THE ISOLATED SHOWERS THAT FORMED ALONG
THE SEA-BREEZE LATE SUNDAY. SIMILAR TO SUNDAY...ANY
SHOWERS/ISOLATED STORMS WILL HOLD OFF UNTIL LATE IN THE
AFTERNOON...MEANING MOST OF THE DAYLIGHT HOURS TODAY WILL BE DRY.
TEMPERATURES CLIMB INTO THE 80S...AND WELL INTO THE 80S AWAY FROM
THE BEACHES. ONCE AGAIN...A WELL-DEFINED SEABREEZE CIRCULATION
WILL BECOMES ESTABLISHED BY 17-18Z. ONCE THE SEABREEZE BEGINS TO
PUSH INLAND...LOW LEVEL FOCUS AHEAD OF THE BOUNDARY WILL
COMPLIMENT THE IMPROVING THERMODYNAMICS ALOFT TO ALLOW A
SCATTERING OF SHOWERS TO DEVELOP ALONG THE I-75 CORRIDOR. GIVEN
THE FLOW PATTERN...MUCH IF NOT ALL THE CONVECTION WILL BE FOCUSED
ALONG THE FLORIDA WEST COAST BY LATE AFTERNOON. FOR NOW...WILL
KEEP RAIN CHANCES ALONG THIS CORRIDOR IN THE 30-50% RANGE AFTER
20Z...HOWEVER...NEIGHBORHOOD ENSEMBLE POPS FROM THE CONVECTION
ALLOWING GUIDANCE SUITE ARE ACTUALLY MORE AGGRESSIVE. SINCE
CONVECTION ALLOWING MODELS ARE OFTEN TOO AGGRESSIVE WITH
CONVECTION...ESPECIALLY THIS TIME OF YEAR...THE 30-50% POPS SEEM
A REASONABLE APPROACH. GIVEN THE MORE UNIFORM THERMODYNAMIC
ENVIRONMENT...WILL EXPECT SOME CONVECTION TO FIRE ALL THE WAY UP
THROUGH THE NATURE COAST TODAY AS WELL. THERE IS A BETTER CHANCE
TODAY THAT UPDRAFTS REACH HEIGHTS CONDUCIVE FOR CHARGE SEPARATION
AND LIGHTING POTENTIAL. THE SCT CONVECTION WILL BE SLOW MOVING
TODAY...BUT SHOULD GENERALLY MIGRATE TOWARD THE COAST AND OFFSHORE
DURING THE EARLY/MID EVENING HOURS...BEFORE DISSIPATING.
THE SHORTWAVE AXIS MAKES A QUICK EXIT TO OUR EAST AND SOUTHEAST
TONIGHT...ALLOWING SUBTLE HEIGHT RISES OVER THE FLORIDA PENINSULA BY
SUNRISE TUESDAY. THIS PROCESS WILL CONTINUE THROUGHOUT TUESDAY AND
RESULT IN WELL DEFINED MID/UPPER RIDGING OVER OUR HEADS BY THE
SECOND HALF OF THE DAY. NEAR THE SURFACE...RIDGING WILL REMAIN IN
CONTROL FROM A HIGH CENTER LOCATED OVER THE WESTERN ATLANTIC. STRONG
TERRESTRIAL HEATING AND WEAK LOW LEVEL FLOW AGAIN ALLOWS SEA-
BREEZE FORMATION TO TURN WINDS ONSHORE AT THE BEACHES AFTER 17Z.
A SIMILAR FLOW PATTERN IN THE LOWER LEVELS TO PREVIOUS DAYS WILL
KEEP THE BEST CONVERGENCE ACROSS THE WESTERN SIDE OF THE FL
PENINSULA. CERTAINLY THE UPPER LEVELS THERMODYNAMICS ARE LESS
FAVORABLE BY TUESDAY AFTERNOON...AS THE RIDGING CONTINUES TO
BUILD...AND THEREFORE WILL SWING THE FORECAST BACK THE OTHER WAY
TOWARD MORE ISOLATED AND SHALLOW CONVECTION LATE TUESDAY
AFTERNOON/EVENING. HIGH TEMPERATURES TUESDAY IN THE MID/UPPER 80S
AWAY FROM THE BEACHES AND LOWER 80S AT THE IMMEDIATE COAST.
&&
.MID/LONG TERM (WEDNESDAY THROUGH NEXT SUNDAY)...
THE MID AND LONG TERM FORECAST PERIODS WILL FEATURE DRY WEATHER
AND ABOVE NORMAL TEMPERATURES FOR WEST CENTRAL AND SW FLORIDA.
SURFACE HIGH PRESSURE WILL REMAIN IN PLACE ACROSS THE WESTERN
ATLANTIC LEAVING US IN A PREDOMINANT E TO SE LOW-LEVEL FLOW FOR
MUCH OF THE WEEK AND INTO NEXT WEEKEND. THE ATMOSPHERE WILL REMAIN
FAIRLY DRY IN THE MID TO UPPER LEVELS AS MOST OF THE AVAILABLE
ATMOSPHERIC MOISTURE WILL REMAIN BELOW THE 700 MB LEVEL. THIS WILL
MAKE THE ENVIRONMENT VERY HOSTILE TO ANY SHOWERS THAT TRY TO
DEVELOP DURING THE AFTERNOON HOURS. ITS POSSIBLE THAT MAYBE A
STRAY SHOWER COULD DEVELOP WITH SEABREEZE INTERACTIONS BUT GIVEN
THE HOSTILE MID/UPPER LEVELS THEY WOULD BE FAIRLY SHALLOW SHOWERS
AND QPF WOULD BE VERY LOW. THAT BEING SAID MOST OF THE AREA CAN
EXPECT TO REMAIN DRY THIS WEEK AND INTO NEXT WEEKEND AND WILL KEEP
POPS BELOW 20 PERCENT AREA WIDE THROUGH THE FORECAST PERIOD.
DAILY AFTERNOON TEMPERATURES ARE EXPECTED TO TOP OUT IN THE MID TO
UPPER 80S...WITH SOME SPOTS REACHING 90 NOT OUT OF THE QUESTION
ACROSS THE INTERIOR. DAILY SEABREEZE DEVELOPMENT IN THE EARLY
AFTERNOON WILL HELP KEEP THE COASTAL REGIONS A TAD COOLER. OVERNIGHT
LOWS WILL BE ON THE MILD SIDE WITH MID TO UPPER 60S EXPECTED...LOWER
70S LIKELY NEAR THE IMMEDIATE COAST.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS WEST-CENTRAL AND SOUTHWEST FLORIDA
EARLY THIS MORNING. LOW POTENTIAL FOR A BRIEF PERIOD OF MVFR MIST
AT KLAL/KPGD AROUND DAWN...BUT OTHERWISE ANTICIPATE THE VFR
CONDITIONS TO PERSIST THROUGH THE MORNING HOURS. SCT SHOWERS AND
EVEN A FEW THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE SEA
BREEZE LATE THIS AFTERNOON (MAINLY AFTER 19-20Z) INTO THE EVENING
HOURS. ANY TERMINAL MAY SEE A BRIEF RESTRICTIONS ASSOCIATED WITH A
PASSING SHOWERS. SHOWERS DISSIPATE AFTER SUNSET.
&&
.MARINE...
THE PATTERN REMAINS STAGNANT THROUGH THE MIDDLE PORTION OF THE
WEEK...WITH HIGH PRESSURE OFF THE EASTERN SEABOARD CONTINUES TO
RIDGE BACK TO THE WEST OVER THE FLORIDA PENINSULA AND EASTERN GULF
OF MEXICO. THE PREDOMINANT LARGE SCALE FLOW AROUND THIS RIDGE
WILL BE FROM THE SOUTHEAST...HOWEVER THE GRADIENT IS WEAK ENOUGH
TO ALLOW WINDS TO TURN ONSHORE NEAR THE COAST EACH AFTERNOON AND
EVENING...BEFORE SWITCHING BACK TO THE SOUTHEAST BY MIDNIGHT EACH
NIGHT. WINDS AND SEAS WILL GENERALLY REMAIN BELOW HEADLINE
CRITERIA FOR SEVERAL DAYS TO COME. MARINERS SHOULD KEEP AN EYE TO
THE EAST LATER THIS AFTERNOON AS SCATTERED THUNDERSTORM ARE
EXPECTED TO DEVELOP ALONG THE I-75 CORRIDOR AFTER 3-4 PM EDT...AND
THEN SLOWLY MIGRATE OFFSHORE THROUGH THE EARLY EVENING HOURS.
STORMS WILL BE MUCH MORE ISOLATED IN NATURE FOR LATER TUESDAY AND
WEDNESDAY.
&&
.FIRE WEATHER...
HIGH PRESSURE AT THE SURFACE CONTINUE TO RIDGE OVER THE REGION FROM
THE WESTERN ATLANTIC THROUGH THE NEXT SEVERAL DAYS. SCATTERED STORMS
ARE ANTICIPATED TO DEVELOP ALONG THE I-4 CORRIDOR LATE THIS
AFTERNOON INTO THE EVENING HOUR BEFORE DISSIPATING AFTER SUNSET.
ONLY ISOLATED SHOWERS ARE EXPECTED LATE TUESDAY AND LATE WEDNESDAY
AFTERNOONS. RELATIVE HUMIDITY VALUES GENERALLY REMAIN ABOVE CRITICAL
LEVELS THROUGH THURSDAY. A FEW SPOTS MAY BRIEFLY REACH 35% ANY
AFTERNOON...HOWEVER...EXTENDED DURATIONS OF CRITICAL RH ARE
UNLIKELY...AND WINDS WILL REMAIN BELOW CRITICAL LEVELS.
THEREFORE...NO RED FLAG CONDITIONS ARE ANTICIPATED THE NEXT SEVERAL
DAYS.
FOG POTENTIAL...ISOLATED POCKETS OF FOG ARE POSSIBLE INLAND EACH
NIGHT THROUGH THURSDAY...HOWEVER NO SIGNIFICANT AREAS OF DENSE FOG
OR VISIBILITY REDUCTIONS ARE ANTICIPATED.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 85 69 86 69 / 50 50 20 10
FMY 86 67 85 67 / 50 50 20 10
GIF 85 66 87 66 / 30 20 20 10
SRQ 80 69 81 67 / 30 30 10 10
BKV 86 64 84 63 / 40 40 20 10
SPG 84 70 84 71 / 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 QUAD CITIES IA IL
315 AM CDT MON APR 25 2016
.SYNOPSIS...
ISSUED AT 315 AM CDT MON APR 25 2016
LOW PRESSURE WAS LOCATED IN EXTREME EASTERN SD WITH A WARM FRONT
INTO SOUTHERN WI AND A COLD FRONT EXTENDING FROM THE LOW INTO
EXTREME EASTERN NEB AND THEN TO SW KS. LINE OF THUNDERSTORMS THAT
WAS IN CENTRAL IA EARLIER IN THE NIGHT HAS RAPIDLY DECAYED THE
PAST COUPLE OF HOURS TO ONLY A FEW SHOWERS. THIS IS DUE TO A MUCH
MORE STABLE AIRMASS OVER THE DVN CWA AND LACK OF SHEAR.
TEMPERATURES WERE MILD EARLY THIS MORNING AS EXPECTED WITH A
STEADY SOUTH WIND AND CLOUD COVER. 3 AM TEMPERATURES WERE MAINLY
IN THE LOWER TO MID 60S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CDT MON APR 25 2016
FORECAST FOCUS ON THE POTENTIAL FOR ISOLATED STRONG OR SEVERE
THUNDERSTORMS LATER TODAY.
TODAY...WHAT FEW SHOWERS THERE ARE EARLY THIS MORNING WILL
CONTINUE TO FADE AWAY LEAVING THE MORNING HOURS (AFTER 6 AM) DRY.
THEN THE FOCUS WILL BE ON IF ANY CONVECTION CAN ERUPT LATER THIS
AFTERNOON AND EVENING. LOW PRESSURE WILL TRACK ACROSS SOUTHERN MN
AND BE NEAR LA CROSSE WI BY EVENING. A WEAK COLD FRONT WILL DRAG
SOUTHEAST INTO THE DVN CWA THIS AFTERNOON. AHEAD OF THE FRONT
TEMPERATURES SHOULD WARM INTO THE UPPER 70S TO LOWER 80S. WITH
DEWPOINTS IN THE MID 50S TO AROUND 60 THIS SHOULD YIELD MUCAPES OF
ABOUT 2000 J/KG AND MLCAPE TO 1000 J/KG. A 50 KNOT MID LEVEL WIND
MAX WILL APPROACH THE AREA AT PEAK HEATING WITH MODERATE DEEP
LAYER SHEAR OF 40 KNOTS. ANY STORMS DEVELOPING IN THIS ENVIRONMENT
SHOULD BE ABLE TO PRODUCE LARGE HAIL AND DAMAGING WINDS.
HOWEVER...THE BIG PROBLEM IS THE LACK OF SUFFICIENT CONVERGENCE
NEAR THE FRONT AS THE WINDS VEER UNIDIRECTIONAL FROM THE SOUTHWEST.
THE HRRR KEEPS THE CONVECTION IN WI CLOSER TO THE SURFACE LOW AND
BETTER FORCING WHILE THE SPC 4.0 KM WRF-NMM FIRES UP CONVECTION
EAST OF THE MS RIVER NOT UNTIL THIS EVENING. THEREFORE...HAVE
KEPT MENTION OF CHANCE POPS IN THE 20-40 PERCENT RANGE AND MAINLY
ALONG AND EAST OF THE MS RIVER LATER THIS AFTERNOON AND EVENING...
AHEAD OF THE FRONT. SPC DOES HAVE A SLIGHT RISK EAST OF THE MS RIVER.
AT THIS TIME WILL KEEP COVERAGE OF THE STORMS TO ISOLATED TO
SCATTERED BUT THE POTENTIAL IS THERE FOR A DRY FROPA...AND LET DAY
SHIFT MONITOR TRENDS.
TONIGHT...ASSUMING CONVECTION FORMS LATER THIS AFTERNOON AND
EVENING THE FRONT WILL HAVE PUSHED EAST OF THE DVN CWA BY LATE
EVENING ENDING ANY RAIN CHANCES. WEST WINDS SHOULD BRING SOMEWHAT
DRIER AIR INTO THE CWA SO LOWS TONIGHT WILL BE COOLER...IN THE 50S.
SKIES WILL BECOME CLEAR OR PARTLY CLOUDY BEHIND THE FRONT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 315 AM CDT MON APR 25 2016
THE FORECAST OF VERY ACTIVE SYNOPTIC PROGRESSIVE LOW PRESSURE
SYSTEMS REMAINS FORECAST BY ALL GLOBAL MODELS TONIGHT FOR THE
EXTENDED FORECAST. THE TREND THAT THESE SYSTEMS WILL PASS JUST SOUTH
OF OUR CWA...OR THROUGH OUR SOUTHERN CWA CONTINUES TO SUGGEST
EXTENDED PERIODS OF NEAR 100 PERCENT POPS WILL BE REQUIRED FOR LATE
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT AND POSSIBLY THURSDAY. ANOTHER
SYSTEM ON THE HEELS OF THE DEPARTING THURSDAY LOW APPEARS SIMILAR
WITH WIDESPREAD STRATIFORM RAIN/EMBEDDED THUNDER FOR LATE FRIDAY
NIGHT THROUGH THE ENTIRE UPCOMING WEEKEND AND POSSIBLY EARLY WEEK
AHEAD. THAT SYSTEM AS THE MOMENT IS SUGGESTED TO END THE PROGRESSIVE
NATURE OF THE SYNOPTIC FLOW...AND CUT OFF INTO A BROAD UPPER LOW
OVER THE EASTERN HALF OF THE CONUS. THIS IS THE CASE IN BOTH THE GFS
AND EC 00Z RUNS. IN ANY CASE...RAIN...AND PLENTY OF IT....IS
FORECAST THIS UPCOMING WEEK...WITH SOME BOUTS OF EMBEDDED THUNDER
LIKELY AS WELL DURING PERIODS OF STRONG WARM ADVECTION ALOFT.
AT THE TIME...WHILE THE WEEK LONG PERIOD OFFERS THE POTENTIAL FOR
WIDESPREAD 1 TO 2 INCHES OF RAIN...WITH SOME AREAS POSSIBLY SEEING
MORE IN MESOSCALE BANDS OF ACTIVITY. THE RAINFALL RATES OVER ALL
SEEM TO OFFER A SOMEWHAT MORE BENIGN FLASH FLOODING FORECAST...AND
A SLOWLY EVOLVING RIVER RISE POTENTIAL.
TEMPERATURES TUESDAY UNDER SHORT TERM HIGH PRESSURE AND LITTLE COLD
ADVECTION SHOULD TOP OUT WELL INTO THE 70S...MAKING FOR A CERTAIN
CANDIDATE FOR THE MOST PLEASANT DAY THIS WEEK. ONCE RAIN AND CLOUDS
ARRIVE TUESDAY NIGHT...THE NEXT DRY DAY WITH ANY PREDICTABILITY MAY
BE FRIDAY. WEDNESDAY THROUGH THURSDAY WILL SEE FAR COLDER
TEMPERATURES AS IN THE LOWER 50S TO LOWER 60S FROM NORTH TO
SOUTH...AS RAIN COOLED AIR PERSISTS NORTH OF THE WARM FRONT. AT THIS
TIME...IT APPEARS THE WET AND CLOUDY WEATHER WILL KEEP US WELL BELOW
NORMAL WELL INTO NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1143 PM CDT SUN APR 24 2016
AREA OF SHOWERS WITH EMBEDDED THUNDER WILL CONTINUE TO WEAKEN AND
GRADUALLY DIMINISH IN COVERAGE WHILE MOVING INTO EASTERN IA
OVERNIGHT. HAVE GONE WITH TEMPO GROUP FOR JUST SHOWERS AT CID
AND HAVE VCSH WORDING AT THE RIVER SITES DUE TO LOWER CONFIDENCE
TIED TO RATE OF DECAY OF ACTIVITY. OTHERWISE... NEXT FOCUS IS
WITH ISOLD TO SCT STORM POTENTIAL FROM MID MONDAY AFTERNOON
THROUGH EARLY EVENING. LIMITED CONVERGENCE LEADS TO LOW CONFIDENCE
ON COVERAGE THUS FOR NOW HAVE HANDLED AS VCTS WORDING AT THE
RIVER SITES BY LATE AFTERNOON INTO EARLY EVENING AHEAD OF COLD
FRONT. OVERALL... EXPECT VFR CONDITIONS OUTSIDE OF THE
PRECIPITATION... WITH MAINLY MVFR IN ANY SHOWERS OR STORMS. HAIL
AND GUSTY WINDS COULD BE A THREAT WITH THE STRONGER PM STORMS ON
MONDAY. WINDS ARE EXPECTED TO BECOME GUSTY TOMORROW FROM SSW AT
15-25 KTS THEN TAPER OFF AND BEGIN TO VEER TO WESTERLY MONDAY EVE
WITH FRONT ARRIVING.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...ERVIN
AVIATION...MCCLURE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
427 AM EDT MON APR 25 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 422 AM EDT MON APR 25 2016
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CONFLUENT NW FLOW
ALF INTO THE UPR LKS BTWN NRN BRANCH CLOSED LO OVER NRN QUEBEC AND A
SRN BRANCH SHRTWV OVER THE WRN GREAT LKS AHEAD OF STRONG SHRTWV
MOVING SLOWLY ENEWD THRU THE NCENTRAL PLAINS. ALTHOUGH MOISTER
AIR...WITH 00Z PWATS AS HI AS 1.16 INCH AT MPX /ALMOST 250 PCT OF
NORMAL/ AND 0.92 INCH AT GRB /190 PCT OF NORMAL/...HAS PUSHED
FARTHER N AHEAD OF THIS SHRTWV AND SFC/H85 LO OVER ERN SDAKOTA...
DRIER AIR ON THE SRN FLANK OF BONE DRY AIRMASS IN ONTARIO /WHERE 00Z
PWAT AT YPL WAS ONLY 0.12 INCH/ MAINTAINED BY PROXIMITY OF THE
CONFLUENCE ZN BTWN THE BRANCHES SLOWED THE ARRIVAL OF HEAVIER RA
THAT HAS BEEN FCST RECENTLY. HOWEVER...LATEST RADAR IMAGERY SHOWS A
BAND OF RA N OF A NEARLY STNRY H85 WARM FNT STRETCHING FM CENTRAL MN
ACRS NCENTRAL WI IS PUSHING NE THRU UPR MI. UPR DVGC IN RRQ OF 120KT
H3 JET MAX OVER SW QUEBEC AS WELL AS SHARP H85-7 FGEN N OF THE ARPCHG
WARM FNT APPEAR TO BE SGNFT FORCING MECHANISMS. BUT THIS BAND IS
RATHER NARROW...WITH DRY SLOTTING IN ADVANCE OF THE APRCHG SHRTWV
CAUSING A SHARP SRN EDGE TO THIS BAND OF HEAVIER RA THAT IS ALREADY
PUSHING N ACRS THE WI BORDER.
MAIN FCST CONCERNS THRU TNGT FOCUS ON POPS/QPF TODAY AHEAD OF SLOWLY
APRCHG SHRTWV AND THEN DRYING TRENDS/POTENTIAL FOR SOME SN TNGT AS
LARGE SCALE SUBSIDENCE/SOMEWHAT COLDER AIR FOLLOW IN THE WAKE OF
SHEARING SHRTWV THRU WI.
TODAY...MODELS IN GOOD AGREEMENT SHOWING BAND OF HEAVIER RA
CONTINUING NE THRU THE CWA BUT TENDING TO DIMINISH AS THE FGEN
FORCING WEAKENS AS THIS BAND MOVES FARTHER N INTO LINGERING DRY AIR
MAINTAINED BY NW FLOW ALF OVER ONTARIO AND AWAY FM NEARLY STNRY FNT
LINGERING IN WI. THEN SOME DRY SLOTTING WILL IMPACT MAINLY THE
SCENTRAL BEFORE DPVA/LARGER SCALE QVECTOR CNVGC IN ADVANCE OF THE
APRCHG SHRTWV ARRIVE W-E AND CAUSE THE PCPN AREA TO EXPAND AGAIN/
INTENSIFY IN THE AFTN. WITH CLD COVER/RA...WL MAINTAIN PREVIOUS FCST
WELL BLO NORMAL MAX TEMPS NOT FAR FM 40.
TNGT...SHRTWV SLIDING ENEWD IS PROGGED TO SHEAR OUT AND MOVE MORE
QUICKLY TO THE E ACRS WI AS IT ENTERS THE UPR CONFLUENCE ZN BTWN THE
NRN AND SRN BRANCHES. WITH DIMINISHING DYNAMIC SUPPORT/MID LVL
DRYING ACCOMPANYING THE SHEARING SHRTWV...EXPECT PCPN COVERAGE/
INTENSITY TO GRDLY DIMINISH. WITH THE ARRIVAL OF COLDER AIR AS THE
LLVL FLOW BACKS MORE TO THE NE...GUIDANCE HINTS THE PCPN WL AT LEAST
MIX WITH SOME SN BEFORE ENDING ESPECIALLY OVER THE NRN TIER AS H85
TEMPS FALL AOB 0C. THE NAM INDICATES SEVERAL INCHES OF WET SN COULD
ACCUMULATE OVER THE HIER TERRAIN OF THE NCNTRL WITH LINGERING SLGTLY
CYC NE UPSLOPE FLOW AIDING COOLING/LIFT. THIS MODEL IS SLOWER THAN
MOST OF THE OTHER GUIDANCE IN SHEARING OUT THE SHRTWV/BRINGING IN
LARGER SCALE QVECTOR DVGC/HOLDING ON TO LLVL CYC FLOW. BUT SINCE
SOME OF THE OTHER HI RES MODELS INDICATE SOME PERSISTENT HIER QPF
OVER THE HIER TERRAIN OF THE NCENTRAL...WL MAINTAIN SOME HIER POPS
IN THIS AREA ALONG WITH A HIER QPF.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 349 AM EDT MON APR 25 2016
UPPER AIR PATTERN WILL FEATURE A COLD UPPER LEVEL TROUGH CENTERED
OVER QUEBEC MOST OF THIS WEEK WITH TROUGHING OVER WESTERN CONUS.
UPPER LAKES WILL RESIDE WITHIN CONFLUENT NW FLOW ALOFT ON EDGE OF
EASTERN CANADA TROUGH. RESULT IS HIGH PRESSURE EXPANDING OVER HUDSON
BAY EARLY THIS WEEK WILL PUSH A RIDGE OVER UPPER GREAT LAKES INTO
NEXT WEEKEND. PATTERN WILL LEAD TO DRY WEATHER WITH SEASONABLY COOL
TEMPERATURES. NO REAL SIGNIFICANT WARM UP IS IN SIGHT ATTM. IN FACT
IF ANYTHING THE 7-10 DAY PERIOD JUST BEYOND REACH OF THIS FORECAST
POINTS TO MORE COOLER AND UNSETTLED PATTERN AS TROUGHING OVER
WESTERN CONUS EVENTUALLY MAKES IT TO THE GREAT LAKES. EXTRAPOLATING
CPC DAY 8-14 OUTLOOK MADE ON APRIL 24TH SUGGESTS THAT WARMER AIR MAY
BEGIN TO MAKE ITS WAY OVER GREAT LAKES TOWARD MID MAY AND CPC 3-4
WEEK OUTLOOK GOOD THROUGH MID-LATE MAY SIGNALS A SWITCH TO ABOVE
NORMAL TEMPS. TIME WILL TELL IF THAT DOES INDEED OCCUR.
LINGERING EFFECTS FROM DEPARTING LOW PRESSURE SYSTEM ARE FEW BUT
COULD SHOW UP AS A FEW RAIN/SNOW SHOWERS EARLY ON TUESDAY...MAINLY
FOR UPSLOPE AREAS OF CNTRL CWA. AT THE LEAST...INCREASED SKY COVER
UNTIL LATE MORNING WHEN DRY AIR WITH THE HIGH BUILDING TO THE NORTH
SHOULD ERODE LOW CLOUDS STEADILY FROM NORTH TO SOUTH. SMATTERING OF
MID OR HIGH CLOUDS MAY TRY TO LINGER OVER SOUTHERN CWA...BUT OVERALL
SHOULD TURN INTO A MOSTLY SUNNY DAY FOR ALL CWA.
NO REAL SIGNIFICANT FORECAST ISSUES REST OF THIS WEEK AS THE HIGH
PRESSURE DOMINATES. SKIES SHOULD BE MOSTLY CLEAR AND WINDS NOT
PARTICULARLY STRONG/GUSTY. GRADIENT ONSHORE NORTHEAST WINDS OUT OF
THE HIGH WILL KEEP LAKE SUPERIOR SHORELINE COOLEST WITH DAYTIME
HIGHS MAINLY IN THE 40S. ELSEWHERE...TEMPS SHOULD GRADUALLY RISE
THROUGH THE 50S BY LATE WEEK. PERHAPS MAY SEE LOWER 60S WELL INLAND
FROM THE GREAT LAKES SHORES BY LATE THIS WEEK INTO NEXT WEEKEND...
BUT THAT WOULD ONLY COME FROM AIRMASS MODERATION AS THE OVERALL
TEMPS ALOFT WARM LITTLE. THE COOL AND DRY AIR MASS WITH THE HIGH
POINTS TO GOING ON LOWER END OF GUIDANCE FOR NIGHTTIME LOWS
ESPECIALLY INLAND.
CONSENSUS OF MODELS BRINGS SLIGHT CHANCES BACK OVER UPR MICHIGAN
NEXT SUNDAY. PREVIOUS ECMWF DROVE THOSE RELATIVELY HIGHER POPS...BUT
LATEST RUN HAS TRENDED FARTHER SOUTH WITH SFC-MID LEVEL LOW LIFTING
ACROSS MID MISSISSIPPI RIVER VALLEY. FARTHER SOUTH TREND WITH PRECIP
MAKES SENSE GIVEN THE STRONG/PERSISTENT/DRY HUDSON BAY HIGH THE
SYSTEM WILL BE RUNNING INTO.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 127 AM EDT MON APR 25 2016
WITH A STATIONARY FRONT REMAINING S OF UPPER MI THRU MON...EXPECT
PERIODS OF RAIN DURING THIS FCST PERIOD WITH CONDITIONS GENERALLY
REMAINING IN THE IFR/LIFR CATEGORY AT ALL SITES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 AM EDT MON APR 25 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 INTO TONIGHT. OVER THE
WESTERN LAKE WHERE COASTAL CONVERGENCE/FUNNELING ENHANCE E TO NE
WINDS...GALE FORCE WINDS ARE EXPECTED THROUGH THIS EVENING. ACROSS
THE REST OF LAKE SUPERIOR...PLAN FOR WINDS OF 20-30KT. WINDS WILL
SLOWLY DIMINISH LATE TONIGHT/TUE MORNING...BUT MORE SO TUE NIGHT AS
THE NORTHERN ONTARIO HIGH PRES BUILDS INTO THE UPPER LAKES. E TO NE
WINDS GENERALLY UNDER 20KT WILL PREVAIL WED...THOUGH GUSTS TO 25 KTS
MAY OCCUR OVER WRN LAKE SUPERIOR. WINDS WILL DIMINISH TO LESS THAN
20KT THU/FRI ACROSS THE ENTIRE LAKE AS HIGH PRES SETTLES OVER THE
AREA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EDT /MIDNIGHT CDT/ TUESDAY FOR LSZ162.
GALE WARNING UNTIL 1 AM EDT TUESDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...07
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
351 AM EDT MON APR 25 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...(TUESDAY THROUGH SUNDAY)
ISSUED AT 349 AM EDT MON APR 25 2016
UPPER AIR PATTERN WILL FEATURE A COLD UPPER LEVEL TROUGH CENTERED
OVER QUEBEC MOST OF THIS WEEK WITH TROUGHING OVER WESTERN CONUS.
UPPER LAKES WILL RESIDE WITHIN CONFLUENT NW FLOW ALOFT ON EDGE OF
EASTERN CANADA TROUGH. RESULT IS HIGH PRESSURE EXPANDING OVER HUDSON
BAY EARLY THIS WEEK WILL PUSH A RIDGE OVER UPPER GREAT LAKES INTO
NEXT WEEKEND. PATTERN WILL LEAD TO DRY WEATHER WITH SEASONABLY COOL
TEMPERATURES. NO REAL SIGNIFICANT WARM UP IS IN SIGHT ATTM. IN FACT
IF ANYTHING THE 7-10 DAY PERIOD JUST BEYOND REACH OF THIS FORECAST
POINTS TO MORE COOLER AND UNSETTLED PATTERN AS TROUGHING OVER
WESTERN CONUS EVENTUALLY MAKES IT TO THE GREAT LAKES. EXTRAPOLATING
CPC DAY 8-14 OUTLOOK MADE ON APRIL 24TH SUGGESTS THAT WARMER AIR MAY
BEGIN TO MAKE ITS WAY OVER GREAT LAKES TOWARD MID MAY AND CPC 3-4
WEEK OUTLOOK GOOD THROUGH MID-LATE MAY SIGNALS A SWITCH TO ABOVE
NORMAL TEMPS. TIME WILL TELL IF THAT DOES INDEED OCCUR.
LINGERING EFFECTS FROM DEPARTING LOW PRESSURE SYSTEM ARE FEW BUT
COULD SHOW UP AS A FEW RAIN/SNOW SHOWERS EARLY ON TUESDAY...MAINLY
FOR UPSLOPE AREAS OF CNTRL CWA. AT THE LEAST...INCREASED SKY COVER
UNTIL LATE MORNING WHEN DRY AIR WITH THE HIGH BUILDING TO THE NORTH
SHOULD ERODE LOW CLOUDS STEADILY FROM NORTH TO SOUTH. SMATTERING OF
MID OR HIGH CLOUDS MAY TRY TO LINGER OVER SOUTHERN CWA...BUT OVERALL
SHOULD TURN INTO A MOSTLY SUNNY DAY FOR ALL CWA.
NO REAL SIGNIFICANT FORECAST ISSUES REST OF THIS WEEK AS THE HIGH
PRESSURE DOMINATES. SKIES SHOULD BE MOSTLY CLEAR AND WINDS NOT
PARTICULARLY STRONG/GUSTY. GRADIENT ONSHORE NORTHEAST WINDS OUT OF
THE HIGH WILL KEEP LAKE SUPERIOR SHORELINE COOLEST WITH DAYTIME
HIGHS MAINLY IN THE 40S. ELSEWHERE...TEMPS SHOULD GRADUALLY RISE
THROUGH THE 50S BY LATE WEEK. PERHAPS MAY SEE LOWER 60S WELL INLAND
FROM THE GREAT LAKES SHORES BY LATE THIS WEEK INTO NEXT WEEKEND...
BUT THAT WOULD ONLY COME FROM AIRMASS MODERATION AS THE OVERALL
TEMPS ALOFT WARM LITTLE. THE COOL AND DRY AIR MASS WITH THE HIGH
POINTS TO GOING ON LOWER END OF GUIDANCE FOR NIGHTTIME LOWS
ESPECIALLY INLAND.
CONSENSUS OF MODELS BRINGS SLIGHT CHANCES BACK OVER UPR MICHIGAN
NEXT SUNDAY. PREVIOUS ECMWF DROVE THOSE RELATIVELY HIGHER POPS...BUT
LATEST RUN HAS TRENDED FARTHER SOUTH WITH SFC-MID LEVEL LOW LIFTING
ACROSS MID MISSISSIPPI RIVER VALLEY. FARTHER SOUTH TREND WITH PRECIP
MAKES SENSE GIVEN THE STRONG/PERSISTENT/DRY HUDSON BAY HIGH THE
SYSTEM WILL BE RUNNING INTO. &&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 127 AM EDT MON APR 25 2016
WITH A STATIONARY FRONT REMAINING S OF UPPER MI THRU MON...EXPECT
PERIODS OF RAIN DURING THIS FCST PERIOD WITH CONDITIONS GENERALLY
REMAINING IN THE IFR/LIFR CATEGORY AT ALL SITES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 AM EDT MON APR 25 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 INTO TONIGHT. OVER THE
WESTERN LAKE WHERE COASTAL CONVERGENCE/FUNNELING ENHANCE E TO NE
WINDS...GALE FORCE WINDS ARE EXPECTED THROUGH THIS EVENING. ACROSS
THE REST OF LAKE SUPERIOR...PLAN FOR WINDS OF 20-30KT. WINDS WILL
SLOWLY DIMINISH LATE TONIGHT/TUE MORNING...BUT MORE SO TUE NIGHT AS
THE NORTHERN ONTARIO HIGH PRES BUILDS INTO THE UPPER LAKES. E TO NE
WINDS GENERALLY UNDER 20KT WILL PREVAIL WED...THOUGH GUSTS TO 25 KTS
MAY OCCUR OVER WRN LAKE SUPERIOR. WINDS WILL DIMINISH TO LESS THAN
20KT THU/FRI ACROSS THE ENTIRE LAKE AS HIGH PRES SETTLES OVER THE
AREA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EDT /MIDNIGHT CDT/ TUESDAY FOR LSZ162.
GALE WARNING UNTIL 1 AM EDT TUESDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...07
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
127 AM EDT MON APR 25 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 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 127 AM EDT MON APR 25 2016
WITH A STATIONARY FRONT REMAINING S OF UPPER MI THRU MON...EXPECT
PERIODS OF RAIN DURING THIS FCST PERIOD WITH CONDITIONS GENERALLY
REMAINING IN THE IFR/LIFR CATEGORY AT ALL SITES.
&&
.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/ THIS EVENING FOR LSZ162.
GALE WARNING FROM 5 AM EARLY THIS MORNING TO 8 PM EDT THIS
EVENING FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1208 AM CDT MON APR 25 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 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1205 AM CDT MON APR 25 2016
SURFACE LOW IN SOUTH DAKOTA WITH A FRONTAL BOUNDARY DRAPED WEST
TO EAST ACROSS THE FORECAST AREA. SITES TO THE NORTH OF THAT
BOUNDARY ARE SOCKED IN WITH IFR OR EVEN LIFR CIGS AND IT WILL
REMAIN THAT WAY ALL NIGHT AND THROUGH AT LEAST PART OF MONDAY.
THIS INCLUDES AXN...STC...AND POSSIBLY RNH. MSP IS SITTING ON THE
EDGE OF VFR CIGS TO THE SOUTH...AND MVFR/IFR JUST TO THE NORTH.
WENT WITH VFR THROUGH 09Z WITH A TEMPO FOR LOWER CIGS...THEN
EXPECT THE LOW STRATUS TO SAG SOUTH AND TAKE OVER. RWF IS FAR
ENOUGH SOUTH THAT VFR IS POSSIBLE THROUGH THE PERIOD. OVERNIGHT
MOSTLY SCATTERED SHOWERS WITH ISOLATED RUMBLES OF THUNDER WILL BE
LIKELY INITIALLY...BUT AS THE NIGHT GOES ON LOOK FOR A TRANSITION
TO JUST SCATTERED SHOWERS AND A LACK OF THUNDER.
KMSP...WEAKENED STORMS APPROACHING NEXT HOUR TWO. THERE MAY NOT BE
ANY THUNDER AT ALL BY THE TIME THEY REACH MSP...BUT CONTINUED TO
MENTION VCTS. VFR COULD LAST LONGER THAN THE TAF INDICATES AS THE
EDGE OF THE LOW CIGS WILL MOVE LITTLE.
/OUTLOOK FOR KMSP/
TUE...VFR. WINDS E 10-15KTS.
WED...MVFR LATE IN THE DAY. SHRA LIKELY. WIND E 15-25KTS.
THU...MVFR PSBL. CHANCE OF SHRA. WIND E 10-15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...RAH
LONG TERM...CLF
AVIATION...SPD
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
421 AM CDT MON APR 25 2016
.Discussion...
Issued at 419 AM CDT MON APR 25 2016
Overview:
A very active pattern starting off with the dying
convection generated from the first of three upper level storm
systems. Several periods of severe weather as well as the potential
for very heavy rains Tuesday night/Wednesday morning highlight the
forecast.
Short Term (Today through Tonight):
The convective line which entered the western CWA late Sunday night
soon fell apart after midnight as instability dried up after sunset.
Expect the weakening trend to continue until all convection
dissipate around sunrise.
The Central/Northern Plains closed upper system which initiated last
nights convection has opened up and will now lift northeast. A weak
frontal boundary or surface trough is expected to lie/stall across
northwest MO today. Low level moisture will continue streaming
northward into the CWA today with an area of stratus advecting
northeast and overspreading a good part of west central MO and
possibly reaching central MO. Satellite imagery shows this cloud
cover has quickly formed early this morning and is headed our way.
North of the above boundary there should be sufficient sunshine to
allow temperatures to max out in the 75-80 range resulting in CAPEs
approaching 1500 J/kg. Low-level convergence appears to be lacking
along this boundary while mid level heights increase as mid-level
ridging commences. Will throw in some slight chance PoPs for this
afternoon should any mesoscale processes allow a storm or two to bubble
up.
Otherwise, will turn attention towards our western CWA as increasing
isentropic ascent over eastern KS with a corresponding h7 vorticity
max could generate some elevated convection near the MO/KS border.
Will only insert slight chance PoPs for this area as overall
confidence on this outcome is low.
Will lower temperatures across the southwestern counties as stratus
is most likely to remain through the day.
Medium Term (Tuesday through Wednesday):
A second storm system will impact our forecast area during this
period with the potential for severe storms and a high likelihood of
significant rainfall, owing to the presence of precipitable water
values in the 99th percentile.
As a deep upper low lifts northeast out of the desert southwest a
surface low will deepen over the Central High Plains. A frontal
boundary, likely the above noted boundary moving into northwest MO
today, extending east from the low and across the southern CWA will
lift north on Tuesday while a dryline strengthens from south central
NE through western OK. Afternoon/evening severe weather is expected
along both boundaries. All forms of severe weather will be possible
with this system.
A second day of severe weather is possible on Wednesday as the slow
moving closed upper system plods through the Central Plains. The
surface low will be west of the CWA. There likely will be ongoing
convection over the eastern CWA Wednesday morning and where any
residual convective boundaries exist will be potential breeding
grounds for redevelopment in the afternoon. In addition the surface
dryline will probably lie over eastern KS and afternoon convection
could easily form along this feature if it indeed ends up there.
Long Term (Thursday through Sunday):
Thursday into the first part of Friday looks relatively quiet as
upper level ridging moves into the region before a third closed
upper level system moves out of the Southern Rockies and generates a
couple rounds of active, possibly severe, convection from Friday
night through the weekend.
&&
.Aviation...(For the 06Z TAFS through 06Z Monday Night)
Issued at 1158 PM CDT SUN APR 24 2016
Light to moderate rain moving through the terminals over the next
couple hours. Rain might hold on at IXD a little longer due to the
orientation of the showers training over that area. Still should see
some improvement in conditions just after 06z at all terminals.
Expect convectively driven NW`ly winds to recover back to the
south/southwest overnight. Expect some moisture to move north through
the day on Monday, which should bring some MVFR CIGs through most of
the day. KSTJ lies on the border of reduced CIGs, so KSTJ might
remain VFR all period long. Expect some improvement in CIGs around
sunset on Monday evening.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...MJ
Aviation...Leighton
[top]
Area Forecast Discussion
National Weather Service Saint Louis MO
355 AM CDT MON APR 25 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 355 AM CDT Mon Apr 25 2016
Main focus today will be chances for thunderstorms.
Convection from early this morning continues to dissipate as the
upper level trof shears out and a loss of low level forcing. As the
trof lifts nwd, height rises build into the area, which shud
suppress convection thru at least the morning hours.
Mdls depict a outflow bndy or pre-frontal trof draped across the
nrn portions of the CWA later today. With the cdfnt remaining N of
the area, this bndy will be the focus for convection this afternoon.
Heating shud be sufficient to erode the cap in place, allowing
storms this afternoon. That said, there is some question on
placement of storms given the lingering convective debris. Still, it
appears there should be enuf MLCAPE, around 1000 J/kg according to
the more conservative GFS, as well as deep layer shear to support a
few potentially severe storms, lingering into the evening hours.
These values seem appropriate given the warm dewpoint bias in the
NAM.
As for temps, the sfc bndy and convective debris mentioned above
lead to uncertainty in the temps for today. Believe the cool spot in
the CWA will be mainly the nrn counties. Believe the warmer areas
will be generally from KJEF to KPPQ and areas to the SE with warmest
temps along a KVIH to KSTL line, just ahead of the surface bndy.
These temps are well depicted in the MOS and have trended at the
warmer MOS for the area. The RAP and local 4km WRF suggest even
warmer temps, but too many questions in cloud cover today to go that
warm attm.
Tilly
.LONG TERM... (Tonight through Sunday)
Issued at 355 AM CDT Mon Apr 25 2016
The weather is about to get a lot more active for this week, with a
sustained period for the threat of severe storms.
An upper level Rex Block covering much of North America will
continue to prevail thru much of this week, with a RIDGE over the
Canadian Prairie and TROFs flanking it on the coasts. Complimenting
this will be a series of strong Pacific storm systems that will run
just south thru the CONUS, 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 be well on its way to becoming absorbed
into the main flow by this evening, but the main focus at this point
will be where an old convective surface boundary will be. Several
models are in good agreement on firing this up either just before
00z/Tue or right at, when the CINH aloft can weaken just enough, and
once it gets going, should be able to sustain development for a good
portion of the evening, if not into the late night. Enough
instability may be able to be tapped during a small window of time
early this evening for isolated severe storms possible.
A cold front will drop down very late tonight into Tuesday and then
stall at some point over our forecast area, probably just north of I-
70, and will maintain a chance for storms. Should be decent
moisture pooling near the front by Tuesday afternoon, and while
shear is sub-par, MLCAPE near the stalled frontal boundary will be
around 3000 J/kg and would support some severe storms thru magnitude
of instability alone.
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 Tuesday night into Wednesday morning.
Along with an increase of broadscale lift, this should result in
elevated storms, with hail as their primary severe threat during
that time.
Heading into Wednesday afternoon and evening, things look much more
muddled than they did 24-48hrs ago, with the severe threat and mode
still heavily dependent on how far north the warm front gets by this
time. Models continue to show enough variation with frontal
position for low-medium confidence, which for forecast purposes for
now will be near or just north of the I-70 corridor. If the rain
coverage is as high as what several model solutions are suggesting,
this may also work to lower the severe potential on this day,
limiting instability more than previously thought. Either way,
shear will increase substantially as the storm system approaches and
instability may not need to be as high as what it was Tuesday anyway
to justify a continuation of a severe risk.
Things dry out briefly from late Thursday thru early Friday 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 to the south.
Otherwise, daytime max temps will begin much above average this
week, but then slide back towards average for late week and the
upcoming weekend. If the models showing the loss of the western
TROF is accurate for late week, this should result in a slide
towards more of a NW flow aloft pattern for the following week, and
could yield a period of more tranquil wx.
TES
&&
.AVIATION... (For the 06z TAFs through 06z Monday Night)
Issued at 1134 PM CDT Sun Apr 24 2016
Still expect terminals to be dry and VFR through the period as
line of showers and thunderstorms should rapidly diminish as it
moves east the next few hours. Otherwise...still expect winds to
gust to around 20kts on Monday.
Specifics for KSTL: Expect dry and VFR conditions the next 30
hours as line of showers and thunderstorms over western Missouri
should rapidly diminish as it moves east. Otherwise...still expect
still expect winds to gust to around 20 kts on Monday.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
250 AM PDT MON APR 25 2016
.SYNOPSIS...SHOWERS AND ISOLATED THUNDERSTORMS ARE LIKELY TODAY
MAINLY NORTH OF INTERSTATE 40 AS A WEATHER SYSTEM MOVES THROUGH THE
REGION. STRONG WINDS AND PATCHY BLOWING DUST CAN ALSO BE EXPECTED
ESPECIALLY ACROSS THE MOJAVE DESERT AND THE SOUTHERN GREAT BASIN.
IMPROVING CONDITIONS EXPECTED TUESDAY BEFORE ANOTHER WEATHER SYSTEM
MOVES IN MIDWEEK WITH ADDITIONAL SHOWER CHANCES AND ANOTHER ROUND OF
SPRING WINDS.
&&
.SHORT TERM...THROUGH TUESDAY NIGHT.
ITS BEEN AN ACTIVE EVENING AND OVERNIGHT PERIOD TODAY AS A FAIRLY
POTENT TROUGH PIVOTS INTO THE REGION. THIS HAS SPARKED SHOWERS AND
ISOLATED THUNDERSTORMS THROUGH THE NIGHT MAINLY ACROSS INYO COUNTY
AND THE SOUTHERN GREAT BASIN. THUNDERSTORMS NEAR DEATH VALLEY WERE
FAIRLY POTENT FOR A FEW HOURS AFTER SUNSET AS THEY WERE SPARKED BY
SURFACE CONVERGENCE ALONG A SOUTHWARD MOVING COLD FRONT AND AIDED BY
STRONG LIFT IN THE LEFT EXIT REGION OF AN INCOMING JET. THUNDERSTORM
ACTIVITY HAS SINCE WANED WITH NO NEW STRIKES DETECTED IN THE PAST
HOUR...HOWEVER WE REMAIN IN THE FAVORABLY DIFFLUENT LEFT EXIT REGION
OF A 80KT JET AT 300MB....WHICH WILL AID IN ADDITIONAL SHOWER
DEVELOPMENT ACROSS OUR REGION THROUGH THE MORNING HOURS. HIGH RES
GUIDANCE INCLUDING THE HRRR BREAK OUT ADDITIONAL SHOWERS IN SOUTHERN
INYO COUNTY EARLY THIS MORNING AND DRIFT THEM EASTWARD TOWARDS THE
LAS VEGAS VALLEY AROUND SUNRISE. STRONG FORCING AND MARGINAL
INSTABILITY COULD RESULT IN A FEW RUMBLES OF THUNDER AS WELL. GIVEN
THE MODEL AGREEMENT IN THIS PARTICULAR PART OF THE FORECAST
AREA...IVE BOOSTED POPS INTO THE LIKELY CATEGORY FOR THE LAS VEGAS
AREA FOR THE MORNING HOURS. BEWARE OF WET AND SLICK
ROADWAYS...THOUGH IM NOT ANTICIPATING MUCH MORE THAN A FEW
HUNDREDTHS FOR MOST AREAS. OUTSIDE OF FAR SOUTHERN
NEVADA...WIDESPREAD SHOWERS AND ISOLATED THUNDERSTORMS CAN BE
EXPECTED TODAY NORTH OF INTERSTATE 40...PARTICULARLY ACROSS THE
SOUTHERN GREAT BASIN WHERE SOME AREAS MAY PICK UP OVER A QUARTER OF
AN INCH OF PRECIPITATION...AND PERHAPS SOME SLUSHY ACCUMULATIONS OF
SNOW ABOVE 6000 FEET.
ASIDE FROM THE PRECIPITATION...THE OTHER BIG CONCERN IS WIND.
HIGHEST IMPACT AREA FROM WIND WILL BE ACROSS THE WESTERN MOJAVE
DESERT PARTICULARLY NEAR DAGGETT AND BICYCLE LAKE. IVE MAINTAINED
THE WIND ADVISORY FOR THESE AREAS IN FAVOR OF THE WIND SPEEDS
ADVERTISED BY OUR HIGH RES MODELS. HOWEVER...MOS GUIDANCE
PARTICULARLY THE MAV HAS BEEN VERY BULLISH WITH HIGH WINDS IN THE
MID AFTERNOON FOR DAGGETT. SO WE WILL NEED TO KEEP AN EYE ON
IT...BUT I HAVE DISCOUNTED IT FOR NOW SINCE IT HAS RUN TOO HIGH IN
RECENT PAST EVENTS. ANTICIPATE PEAK GUSTS IN THE 50 TO 55 MPH RANGE
FOR MOST AREAS IN THE WESTERN MOJAVE DESERT....THOUGH A COUPLE
ISOLATED LOCATIONS MAY EXCEED THAT. GUSTY NORTHWEST WINDS WILL ALSO
MATERIALIZE IN THE SOUTHERN GREAT BASIN BEHIND THE COLD FRONT.
IMPROVING CONDITIONS ARE EXPECTED TUESDAY AS A SHORTWAVE RIDGE
BUILDS IN AND TEMPERATURES WARM CLOSER TO SEASONAL NORMALS.
.LONG TERM...WEDNESDAY THROUGH SATURDAY.
THE PROGRESSIVE PATTERN CONTINUES WITH YET ANOTHER PACIFIC TROUGH
FORECAST TO DIVE ACROSS NORTHERN CALIFORNIA WEDNESDAY AND SPIN INTO
A CLOSED UPPER LOW OVER THE DESERT SOUTHWEST WEDNESDAY NIGHT AND
THURSDAY. THE MEDIUM RANGE MODELS ARE IN FAIRLY GOOD AGREEMENT WITH
THE TRACK AND TIMING OF THIS SYSTEM THROUGH THURSDAY AND CONFIDENCE
IS HIGH THAT COOL AND SHOWERY WEATHER WILL OCCUR AGAIN ACROSS THE
FORECAST AREA WEDNESDAY AFTERNOON THROUGH THURSDAY. THE SYSTEM WILL
HAVE LIMITED MOISTURE DUE TO THE INLAND TRACK AND PRECIPITATION
AMOUNTS DO NOT LOOK IMPRESSIVE. THE PROBABILITY OF ANY PARTICULAR
POINT SEEING MEASURABLE PRECIPITATION IS 30-40 PERCENT IN THE
VALLEYS/DESERTS AND 50-60 PERCENT IN THE MOUNTAINS. SNOW LEVELS WILL
GENERALLY BE AROUND 7000 FEET THOUGH MAY DIP TO AROUND 6000 FEET IN
THE SOUTHERN SIERRA WEDNESDAY NIGHT.
THE LOW CENTER IS FORECAST TO LIFT ACROSS THE FOUR CORNERS REGION
FRIDAY THOUGH SOME LINGERING MOISTURE AND INSTABILITY ON THE BACK
SIDE OF THE TROUGH MAY KEEP A CHANCE OF SHOWERS GOING OVER THE
MOUNTAINS AND ZONES NORTH AND EAST OF LAS VEGAS FRIDAY AND TO A
LESSER EXTENT SATURDAY. THE OPERATIONAL MEDIUM RANGE MODELS INDICATE
ANOTHER SHORTWAVE TROUGH WILL DROP OVER EASTERN WA/OR AND IDAHO
SATURDAY THEN SLIDE DOWN THE NEVADA/UTAH BORDER SATURDAY NIGHT AND
SUNDAY. THIS WOULD PRIMARILY LEAD TO GUSTY NORTH WINDS AND COOLER
TEMPERATURES SUNDAY AND ALSO THE POSSIBILITY OF SHOWERS OVER LINCOLN
AND MOHAVE COUNTIES. CONFIDENCE IN ANY DETAILS BUT WILL TREND TEMPS
AND WINDS TOWARD THIS SCENARIO.
&&
.AVIATION...FOR MCCARRAN...CLOUDS WILL RAPIDLY INCREASE PRIOR TO
SUNRISE WITH SHOWERS DEVELOPING IN THE VICINITY OF THE AIRFIELD
BETWEEN 12-15Z. A PERIOD OF LIGHT RAIN IS PROBABLE THROUGH THE
MORNING HOURS WITH CIGS IN THE 4-6K RANGE AND MOUNTAIN OBSCURATIONS
LIKELY. WINDS WILL CONTINUE TO FAVOR A SOUTH OR SOUTHWEST DIRECTION
GENERALLY IN THE 9-12 KNOT RANGE...THOUGH OCCASIONAL STRONGER PULSES
CAN BE EXPECTED ESPECIALLY PRIOR TO THE ARRIVAL OF SHOWER ACTIVITY.
PERIODIC GUSTS TO 25 KNOTS POSSIBLE DURING THOSE PERIODS. IMPROVING
CONDITIONS EXPECTED IN THE AFTERNOON WITH CIGS RISING CLOSER TO 10K
WHILE CLOUDS BECOME MORE SCATTERED BUT ISOLATED SHOWERS REMAIN
POSSIBLE. BREEZY SOUTHWEST WINDS WILL CONTINUE INTO THE AFTERNOON AS
WELL IN THE 12-18KT RANGE WITH GUSTS TO 25KTS.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...WIDESPREAD SHOWERS AND ISOLATED THUNDERSTORMS EXPECTED
TODAY MAINLY NORTH OF INTERSTATE 40. EXPECT REDUCED CIGS ESPECIALLY
IN THE MORNING HOURS AND MOUNTAIN OBSCURATIONS...WITH POCKETS OF
TURBULENCE. STRONG WINDS EXPECTED ALONG A BELT FROM THE WESTERN
MOJAVE DESERT EASTWARD TOWARDS THE COLORADO RIVER. SITES SUCH AS
KNXP AND KDAG CAN ANTICIPATE WESTERLY WIND GUSTS OVER 45KTS ALONG
WITH AREAS OF BLOWING AND SUSPENDED DUST.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION IS NOT
ANTICIPATED THIS WEEKEND. HOWEVER, SPOTTERS SHOULD REPORT ANY
SIGNIFICANT WEATHER ACCORDING TO STANDARD OPERATING PROCEDURES.
&&
$$
SHORT TERM/AVIATION...OUTLER
LONG TERM...ADAIR
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS ELKO NV
229 AM PDT MON APR 25 2016
.SYNOPSIS...A COUPLE STORMS WILL IMPACT THE GREAT BASIN THIS
WEEK. SNOWFALL MAY IMPACT TRAVEL ACROSS SUMMITS AND OVERPASSES
TODAY AND ACCUMULATION MAY OCCUR ON ALL ROADWAYS TONIGHT BEFORE
THE STORM EXITS. THE NEXT STORM WILL MOVE THROUGH WEDNESDAY AND
THURSDAY...BRINGING VALLEY RAIN AND MOUNTAIN SNOW.
&&
.SHORT TERM...TODAY THROUGH WEDNESDAY. IR SATELLITE IMAGERY
DENOTES THE CENTER OF THE UPPER LEVEL CIRCULATION NEAR BISHOP
CALIFORNIA AT THIS HOUR WITH MOST LIGHTNING OCCURRING SOUTH OF
CENTRAL LOW PRESSURE NEAR THE LEFT FRONT OF THE JET CORE AROUND
BEATTY NEVADA. THERE IS SOME BLOSSOMING CLOUD TOPS NORTHEAST OF
BEATTY AND OVER AUSTIN TO THE NORTH. MESOWEST DATA SHOWS THE
COLD AIR HAS LOWERED TO ABOUT 5500 FEET IN THE NORTH AND ABOUT
6500 FEET ACROSS EAST CENTRAL NEVADA. STILL PURE RAIN AT ELKO WITH
TEMPERATURE DIPPING INTO THE MID 30S. SNOW LEVEL HAS LOWERED BY
ABOUT 500 FEET THIS MORNING. MOST VALLEY LOCATIONS ARE IN THE MID
30S. WORKING TOWARDS A SECOND TENTH OF RAIN AT LKN SINCE 00Z.
MODELS SEEM TO BE IN PRETTY GOOD AGREEMENT FOR THE SHORT TERM
PERIOD.
TODAY THROUGH TONIGHT. THIS IS THE PERIOD WHERE MOST OF THE
ACTION TAKES PLACE. THERE WILL BE SOME VALLEY SNOW
ACCUMULATION...SOME TRAVEL IMPACTS DUE TO LIGHT SNOW ACCUMULATION
ON THE ROADWAYS AND POSSIBLE BLOWING SNOW REDUCING VISIBILITY AT
TIMES...AND HEAVY AMOUNTS OF SNOW ON THE MOUNTAINS. A LOW PRESSURE
TROUGH HAS SETTLED OVER THE GREAT BASIN MUCH AS THE MODELS
IMPLIED. MOISTURE HAS POOLED OVER CENTRAL NEVADA. MODELS INDICATE
A SURFACE FEATURE SHOULD BE POSITIONED OVER LAS VEGAS WITH ONE OF
TWO LOBES EXTENDING NORTH THROUGH ELKO. THIS CAN BE CONFIRMED BY
THE SHOWERS MOVING TO THE NORTH EAST OF ELKO AND TO THE SOUTH WEST
OF ELKO. THE SURFACE LOW WILL MOVE EAST OUT AHEAD OF THE UPPER
LOW AND BRING THE COLD POOL FURTHER EAST. A PRIME WRAP-AROUND
MOISTURE SET-UP FOR WEST OF THE RUBY MOUNTAINS WILL LAST THROUGH
ABOUT 18Z THEN FOCUS ON THE RUBIES EAST SIDE AFTER 18Z. THE RUBIES
BENEFIT FROM A GOOD MOIST FLOW THE ENTIRE TIME AS DOES NORTHERN
ELKO COUNTY. MOST VALLEY LOCATIONS WITH ELEVATIONS ABOVE 5500
FEET SHOULD SEE 2-5 INCHES OF SNOW BY MONDAY AFTERNOON. LOCATIONS
ALONG THE NORTHERN SLOPES OF MOUNTAINS SUCH AS SPRING CREEK IN
ELKO COUNTY MAY SEE HIGHER SNOW AMOUNTS DUE TO UPSLOPE ENHANCEMENT
WITH THE NORTHERLY WINDS. THE JARBIDGE WILDERNESS AREA NEAR THE
IDAHO BORDER WITH ELKO COUNTY COULD RECEIVE 1-2 FEET OF SNOW...AS
COULD THE RUBY MOUNTAINS. TOWARDS THE WEST...WIND GUSTS OVER 40
MPH COULD PRODUCE VISIBILITY ISSUES FOR TRAVELERS WHEN COMBINED
WITH SNOW.
TUESDAY THROUGH TUESDAY NIGHT. SHOWERS WILL TAPER OFF OVER
EASTERN NEVADA IN THE AFTERNOON.
WEDNESDAY. THE NEXT SYSTEM WILL MOVE SOUTH NEAR THE SIERRAS. THE
ECMWF MODEL STILL HAS THE LOW CENTER PLUNGING EAST OF THE
SIERRAS...SIMILAR TO THE PREVIOUS TWO LOWS AND A MORE FAVORABLE
PATTERN FOR PRECIPITATION. HOWEVER THE LATEST GFS MODEL RUN NOW HAS
THE LOW MOVING THROUGH CALIFORNIA...A DRIER SCENARIO DUE TO THE
RAIN SHADOWING ASPECT OF THE SIERRAS. INDICATIONS ARE THAT THIS
SYSTEM WILL SPREAD RAIN SHOWERS ALL ACROSS THE CWFA BY WEDNESDAY
AFTERNOON.
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY. UPPER LOW OVER THE REGION
WILL BRING SHOWERS TO THE AREA WEDNESDAY NIGHT AND THURSDAY, WITH
SHOWERS TAPERING OFF ON FRIDAY AS UPPER RIDGE BEGINS TO BUILD INTO
THE REGION. SNOW LEVELS WILL REMAIN ABOVE 7000 FEET. A FEW SHOWERS
POSSIBLE OVER THE WEEKEND ACROSS EASTERN NV AS UPPER LOW DROPS SOUTH
THROUGH THE AREA. DRY AGAIN ON MONDAY AS RIDGE BUILDS IN.
&&
.AVIATION...LOW PRESSURE SYSTEM OVER THE AREA WILL BRING WIDESPREAD
SHOWERS, WITH SNOW OR MIXED RAIN AND SNOW AS LOW AS 5000 FEET. AREAS
OF MVFR CONDITIONS WITH LOCAL IFR CONDITIONS EXPECTED. STRONG
SURFACE PRESSURE GRADIENT WILL BRING WIND GUSTS UP TO 45KTS AT THE
KTPH TERMINAL AFTER 16Z WITH WINDS SLOWLY DIMINISHING AFT 02Z.
&&
.HYDROLOGY...RIVERS CREEKS AND STREAMS HAVE BEEN FLOWING WITHOUT
MUCH INCIDENT THIS SPRING SEASON AND IT HAS BEEN NICE TO HAVE THE
WATER BACK. HOWEVER WITH THE EXPECTED NEW SNOWFALL...PERIODS OF RAIN
ON SNOW...AND PROJECTED WARMER TEMPERATURES BY THE MIDDLE OF NEXT
WEEK...SOME CREEKS RUNNING OFF THE MOUNTAINS MAY EXCEED BANK-FULL.
LAMOILLE CREEK...MARTIN CREEK...AND SALMON FALLS CREEK ARE THREE NAMED
CREEKS TO WATCH IF SNOW-MELT ESCALATES HOWEVER THERE ARE NUMEROUS
SMALL CHANNELS ORIGINATING IN THE MOUNTAINS THAT MAY CAUSE
FLOODING ISSUES OR SOGGY ROADWAYS.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 11 PM PDT MONDAY FOR NORTHERN ELKO
COUNTY-RUBY MOUNTAINS/EAST HUMBOLDT RANGE.
WIND ADVISORY FROM 9 AM TO 5 PM PDT MONDAY FOR HUMBOLDT COUNTY.
WINTER WEATHER ADVISORY FROM 3 AM TO 3 PM PDT MONDAY FOR
NORTHEASTERN NYE COUNTY-NORTHERN LANDER COUNTY AND NORTHERN
EUREKA COUNTY-SOUTH CENTRAL ELKO COUNTY-SOUTHERN LANDER COUNTY
AND SOUTHERN EUREKA COUNTY-SOUTHWESTERN ELKO COUNTY-WHITE PINE
COUNTY.
WIND ADVISORY FROM 5 AM TO 11 PM PDT MONDAY FOR NORTHWESTERN NYE
COUNTY.
&&
$$
92/91/91
[top]
Area Forecast Discussion...UPDATED
National Weather Service Reno NV
912 PM PDT SUN APR 24 2016
.UPDATE...
Latest radar/satellite imagery and surface reports indicate light
scattered rain/snow showers across the region with thunderstorms
remaining isolated due to the lack of surface heating and only
weak large scale forcing. Colder air was advecting into far
northeast CA and northwest NV where temperatures had fallen into
the 30s. So precipitation in these areas is likely switching over
to snow. The 00z GFS continues to show a band forming across
northwest NV this evening and then shifting east and south Monday
morning while the NAM/latest HRRR are much lighter with the QPF.
While latest radar trends make confidence of the GFS scenario a
bit lower, there is still time for this band to form based on
current track of upper low. So we will continue the snow advisory
for Surprise Valley and northwest NV.
As the band works southeast, light rain and mountain snow will
continue across the basin and range into Monday morning, possibly
extending back into the Reno-Carson City area. We are not
anticipating any commute issues for the I-80/Hwy 50 corridors as
valley temperatures will be a bit too warm. The gradient will
tighten overnight and brisk northwest winds are expected across
the area for Monday. Also, latest model projections show the
airmass stabilizing along and north of I-80 during the afternoon.
So showers may be mostly south and east of Reno-Lovelock in the
afternoon. Hohmann
&&
.PREVIOUS DISCUSSION... /Issued 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 until 8 AM PDT Monday NVZ005.
CA...Winter Weather Advisory until 8 AM PDT Monday CAZ070.
&&
$$
For more information from the National Weather Service visit...
http://weather.gov/reno
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
406 AM CDT MON APR 25 2016
.SHORT TERM (TODAY THROUGH TUESDAY)...
THE POSSIBILITY OF STRONG TO SEVERE THUNDERSTORMS WILL BE THE
MAIN HIGHLIGHT OF THIS FORECAST PERIOD LATE AFTERNOON TUESDAY
INTO EARLY WEDNESDAY MORNING. LARGE HAIL AND DAMAGING WINDS APPEAR
TO THE PRIMARY THREATS AT THIS TIME. PLEASE STAY TUNED FOR FURTHER
UPDATES AS TIMING AND EVOLUTION BECOME MORE CLEAR.
LOW-LVL MOISTURE IS STREAMING IN ON SOUTHEAST WINDS THIS MORNING
AND CREATING WIDESPREAD OVERCAST SKY CONDITIONS. CLOUDS WILL
SLOWLY DISSIPATE THROUGH THE LATE MORNING WITH MORE SUN EXPECTED
THIS AFTERNOON. WITH SOUTH TO SOUTHWEST 925-700MB WINDS,
TEMPERATURES WILL CLIMB ABOVE NORMAL INTO THE UPPER 80S TO LOW 90S
WITH SOME MID 90S POSSIBLE ACROSS THE RIO GRANDE. AS FURTHER
HEATING OCCURS THIS AFTERNOON, DEWPOINTS WILL MIX OUT INTO THE LOW
TO MID 60S WITH PWATS NEAR 1.4". LACK OF DEEPER MOISUTRE AND A MID
TO UPPER LEVEL TRIGGER MAY NOT ALLOW FOR SHOWER OR STORM
GENERATION THIS AFTERNOON DESPITE THE NEAR 3000 J/KG SBCAPE. A
CAPPING INVERSION IN PLACE MAY JUST BE SLIGHTLY TOO STRONG FOR
THUNDERSTORM INITIATION ON PARCEL BUOYANCY ALONE. THE NEW SPC
SSEO DOES SUGGEST SOME ACTIVITY COULD BE POSSIBLE IN THE 7-10PM
RANGE WHILE HRRR AND TEXAS TECH WRF DO NOT AGREE. GLOBAL MODELS
SHOW HINTS OF VERY ISOLATED ACTIVITY. IF A STORM WAS ABLE TO BREAK
THROUGH THE CAP...IT COULD BECOME STRONG GIVEN THE STEEP LAPSE
RATES IN PLACE. WILL HAVE MENTION SUPER LOW END CHANCES WITH
SLIGHT CHANCE THUNDER WORDING FOR WEAKER CAPPING AREAS THIS
AFTERNOON. A QUIET OVERNIGHT INTO TUESDAY MORNING IS EXPECTED WITH
LOW CLOUDS BUILDING BACK INTO THE REGION.
H5 HEIGHT FALLS WILL BEGIN EARLY TUESDAY MORNING ACROSS THE BIG
BEND OF TEXAS THAT MAY HELP SPARK OFF A FEW SHOWERS OVER THE
EDWARDS PLATEAU. MOST OF THIS ACTIVITY SHOULD STAY NORTH OF THE
REGION THROUGH THE EARLY AFTERNOON. A POWERFUL WEATHER SYSTEM
WILL PIVOT ACROSS THE SOUTHERN PLAINS DURING THE AFTERNOON. THE
STRONGEST FORCING WILL REMAIN NORTH WHERE THE BULK OF SEVERE
STORMS ARE EXPECTED. FARTHER SOUTH - CAPPING WILL INITIALLY KEEP
SHOWER AND STORM COVERAGE AT BAY UNTIL THE LATE AFTERNOON HOURS.
BUFR SOUNDINGS INDICATE THE INVERSION WEAKENING BY 4-6PM AND
INCREASED COVERAGE COULD OCCUR DURING THIS TIME OVER THE HILL
COUNTRY TO POSSIBLY THE I35 CORRIDOR. CONTINUED STEEP LAPSE RATES
NEAR 8 C/KM AND 30-40 KT DEEP LAYER SHEAR SHOULD SUPPORT STRONG TO
SEVERE STORMS. THE SPC HAS EXPANDED THE SLIGHT RISK OF SEVERE
STORMS FARTHER SOUTH AND WEST TUESDAY AFTERNOON AND INTO THE
OVERNIGHT. LARGE HAIL AND STRAIGHT-LINE DAMAGING WINDS WILL BE
THE MOST LIKELY HAZARDS BUT A TORNADO CAN NOT BE RULED OUT. LOW-
LVL SHEAR DOES NOT LOOK TO BE OVERLY IMPRESSIVE BUT 0-3KM SHEAR
VECTOR ORIENTATION SHOULD SUPPORT SEMI-DISCRETE STORMS THAT COULD
ACT TO SUPPORT THE LOW-END TORNADO RISK. ADDITIONAL HEIGHT FALLS
THROUGH MIDNIGHT FROM A SECONDARY IMPULSE COULD HELP ORGANIZE THE
STORMS INTO A LINE AND SHIFT IT SOUTHEAST THROUGH WEDNESDAY
MORNING. OVERALL STRENGTH OF THE LINE SHOULD DECREASE BUT SOME
CONTINUED STRONG STORMS COULD BE POSSIBLE. POCKETS OF HEAVY RAIN
WILL ALSO BE POSSIBLE BUT OVERALL COVERAGE SHOULD BE LOW ENOUGH TO
PRECLUDE A FLASH FLOOD WATCH. THIS ACTIVITY A SHOULD HELP FORCE
THE DRYLINE BOUNDARY THROUGH MOST OF THE REGION WEDNESDAY WITH
DRYING AND CLEARING THROUGH THE DAY.
&&
.LONG TERM (WEDNESDAY THROUGH SUNDAY)...
A CONTINUED ACTIVE PATTERN WILL PERSIST LATE WEEK AND EARLY
WEEKEND WITH SOME POTENTIAL IMPACTS FROM HEAVY RAINFALL AND
ANOTHER POSSIBILITY OF STRONG TO SEVERE STORMS.
THE DRYLINE/BOUNDARY SHOULD BE ALONG TO JUST INLAND FROM THE COAST
ON WEDNESDAY WITH DRIER AIR IN PLACE OVER MUCH OF SOUTH-CENTRAL
TEXAS. HOWEVER, BY THURSDAY, THE BOUNDARY WILL SHIFT BACK WEST TO
THE RIO GRANDE AS A SURFACE LOW DEVELOPS NEAR THE BIG BEND WITH
ANOTHER NEGATIVE TILTED TROUGH SWINGING ACROSS THE SW CONUS. AN
IMPLIED IMPULSE AHEAD OF THE PARENT LOW IS DEPICTED IN THE GFS/GEM
AND THIS COULD HELP GENERATE SCATTERED SHOWERS AND THUNDERSTORMS
THURSDAY AFTERNOON. WILL NEED TO MONITOR IF THESE CAN BECOME
STRONG TO SEVERE.
FRIDAY INTO SATURDAY WILL FEATURE THE PARENT CUT-OFF LOW MOVING
OVER NORTH TEXAS INTO THE GREAT PLAINS WITH A STRONG DIFFLUENT
UPPER JET STRUCTURE OVER SOUTH TEXAS. PWATS IN THE 1.6-1.9" ARE
PROGGED TO BE IN PLACE AS DECENTLY AGREED UPON MODEL GUIDANCE
SUGGESTS STRONG SYNOPTIC VERTICAL MOTION IN PLACE. THIS SET-UP
COULD LEAD TO PERIODS OF HEAVY RAIN FRIDAY AFTERNOON INTO SATURDAY
ALONG WITH STRONG TO SEVERE HAZARDS. THIS TIMEFRAME WILL NEED TO
WATCHED CLOSELY THROUGH THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 88 71 86 66 87 / 10 10 30 60 10
AUSTIN BERGSTROM INTL AIRPORT 87 70 86 66 86 / 10 10 30 60 10
NEW BRAUNFELS MUNI AIRPORT 88 70 87 66 87 / 10 10 30 50 10
BURNET MUNI AIRPORT 86 68 85 61 85 / 10 10 30 70 10
DEL RIO INTL AIRPORT 92 70 93 62 90 / - - 10 20 -
GEORGETOWN MUNI AIRPORT 85 70 85 64 86 / 10 10 30 70 10
HONDO MUNI AIRPORT 92 70 88 64 89 / 10 10 20 40 10
SAN MARCOS MUNI AIRPORT 87 70 86 66 86 / 10 10 30 50 10
LA GRANGE - FAYETTE REGIONAL 85 71 86 69 86 / 10 10 20 50 20
SAN ANTONIO INTL AIRPORT 89 71 86 67 87 / 10 10 30 50 10
STINSON MUNI AIRPORT 90 71 89 68 88 / 10 10 20 40 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...17
SYNOPTIC/GRIDS...ALLEN
AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION CAN BE SEEN AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
318 AM PDT MON APR 25 2016
.SYNOPSIS...
PARTLY CLOUDY OVERNIGHT WITH SOME INCREASE IN HIGH CLOUDS LATER
TONIGHT...AND TEMPERATURES A LITTLE ABOVE NORMAL. COOLER ON MONDAY
WITH INCREASING CLOUDS...STRONG AND GUSTY WEST WINDS...AND A CHANCE
FOR LIGHT SHOWERS OVER AND WEST OF THE MOUNTAINS. DRY AND A LITTLE
WARMER FOR TUESDAY AND MOST OF WEDNESDAY UNDER WEAK HIGH PRESSURE
ALOFT. SIGNIFICANT COOLING AGAIN FOR LATE WEDNESDAY AND THURSDAY
WITH A CHANCE FOR SHOWERS AND MOUNTAIN SNOW...ALONG WITH GUSTY WEST
WINDS IN THE MOUNTAINS AND DESERTS. THE SHOWERS TAPER OFF ON
FRIDAY...BUT CONDITIONS REMAIN COOL BEFORE WARMING NEXT WEEKEND AS A
RIDGE ALOFT BUILDS.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
CLOUDY THIS MORNING WITH A FEW SHOWERS MOVING EAST AT ABOUT 20
MPH...MOSTLY OVER THE SAN BERNARDINO MTNS AND THE HIGH DESERTS
WHERE A FEW HUNDREDTHS TO NEAR TWO TENTHS OF AN INCH OF RAIN HAS
FALLEN IN SOME LOCATIONS. ABOVE 7000 FT...A DUSTING OF SNOW WAS
OBSERVED AT A FEW LOCATIONS. ELSEWHERE WEST OF THE MTNS...TRACE
AMOUNTS WERE REPORTED AT A FEW LOCATIONS. THE WINDS HAVE INCREASED
FROM THE WEST AND SEVERAL LOCATIONS IN THE MTNS HAVE REPORTED WIND
GUSTS OF 50-60 MPH.
THE TROUGH OF LOW PRESSURE RESPONSIBLE FOR THE WINDS AND SHOWERS
WILL MOVE THROUGH CALIFORNIA TODAY AND INTO THE ROCKIES BY TUE
MORNING. EXPECT COOL AND UNSETTLED WEATHER TO CONTINUE THROUGH
THIS EVENING...WITH ISOLATED SHOWERS TAPERING OFF BY MIDNIGHT.
MOST OF THE PRECIP WILL FALL OVER AND WEST OF THE MTNS..ALTHOUGH
ACCUMULATIONS ARE EXPECTED TO BE LESS THAN 0.25 INCH AND MOST
LOCATIONS WILL RECEIVE LITTLE OR NO RAIN. THE WEST WINDS WILL
CONTINUE TO INCREASE THROUGH THE MORNING...PEAKING IN THE
AFTERNOON/EVENING...THEN WEAKENING OVERNIGHT.
FAIR AND WARMER ON TUE AND WED AS THE LOW PRESSURE TROUGH MOVES
EAST AND A RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST AHEAD OF
ANOTHER COLDER...LOW PRESSURE SYSTEM APPROACHING FROM THE
NORTHWEST.
DETERMINISTIC MODELS CONTINUE TO SHOW A LOW PRESSURE SYSTEM
MOVING IN FROM THE NORTHWEST LATE WEDNESDAY THROUGH
THURSDAY...CREATING A MORE SIGNIFICANT COOL-DOWN...INCREASING
CLOUDS...GUSTY WINDS IN THE MOUNTAINS AND DESERTS AND A CHANCE FOR
PERIODS OF LIGHT TO MODERATE SHOWERS. WHILE THE MODELS ARE IN
FAIRLY GOOD AGREEMENT ON THE GENERAL PATTERN...THE DETAILS OF
TIMING...TRAJECTORY AND PRECIP AMOUNTS REMAIN UNCERTAIN. MOST
MODEL SOLUTIONS BRING THE COLD POOL OF THE UPPER LOW CLOSE TO...OR
OVER...SOUTHERN CALIFORNIA...SO SOME LOCALLY HEAVIER SHOWERS
AND/OR THUNDERSTORMS ARE A POSSIBILITY. SNOW LEVELS LOWER TO
AROUND 6500-7500 FEET WITH A FEW INCHES OF SNOW POSSIBLE ABOVE
THAT ELEVATION.
THERE MAY BE A FEW LINGERING SHOWERS FRIDAY AS THE TROUGH SLOWLY
MOVES EAST. MODELS ARE NOW IN MUCH BETTER ALIGNMENT FOR NEXT
WEEKEND...AS THEY BOTH INDICATE RIDGING BUILDING IN FROM THE
WEST AND WEAK OFFSHORE SFC PRESSURE GRADIENTS...WHICH WOULD
RESULT IN DRY AND WARM CONDITIONS.
&&
.AVIATION...
250900...COAST/VALLEYS...BKN020-030 WITH TOPS TO 5000 FEET MSL THIS
MORNING. GRADUAL SCATTER OUT FROM THE COAST TO VALLEYS AND COASTAL
SLOPES BY MIDDAY. ISOLATED LIGHT SHOWERS. WESTERLY WINDS INCREASING
TO 15-20 KT AFTER 16Z WITH GUSTS 25-30 KT.
MOUNTAINS/DESERTS...WINDY. NORTHWEST WINDS 20-30 KT GUSTING IN SPOTS
TO 50-60 WITH LLWS AND STRONG UDDFS IN LEE OF MOUNTAINS. SURFACING
MOUNTAIN WAVES AND ROTORS OVER THE DESERTS THROUGH TUESDAY MORNING
POSSIBLY IMPACTING PSP AND TRM. PARTIAL MOUNTAIN OBSCURATION ON
COASTAL SLOPES THROUGH 18Z THIS MORNING WITH ISOLATED SHOWERS.
&&
.MARINE...
200 AM...GALE FORCE GUSTS TODAY AND TONIGHT...DECREASING OVERNIGHT.
NORTHWEST SWELL PEAKING TODAY AND TONIGHT BEFORE DIMINISHING
TUESDAY. HIGHEST WINDS AND SEAS WILL OCCUR NEAR AND SOUTH OF SAN
CLEMENTE ISLAND. FOR DETAILS CHECK THE GALE WARNING...LAXMWWSGX.
&&
.BEACHES...
200 AM...A BIG SHORT PERIOD SWELL WILL PEAK TODAY AND TONIGHT BEFORE
DIMINISHING TUESDAY. STRONG RIP CURRENTS WILL RESULT. FOR DETAILS
CHECK THE BEACH HAZARDS STATEMENT...LAXCFWSGX...AND THE SURF
FORECAST...LAXSRFSGX.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...WIND ADVISORY UNTIL 11 PM PDT THIS EVENING 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.
WIND ADVISORY FROM NOON TODAY TO 9 PM PDT THIS EVENING FOR
ORANGE COUNTY COASTAL AREAS-ORANGE COUNTY INLAND AREAS-SAN
BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-
SAN DIEGO COUNTY COASTAL AREAS-SAN DIEGO COUNTY VALLEYS-
SANTA ANA MOUNTAINS AND FOOTHILLS.
BEACH HAZARDS STATEMENT THROUGH TUESDAY EVENING FOR ORANGE
COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS.
PZ...GALE WARNING UNTIL 11 PM PDT THIS EVENING 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...PG
AVIATION/MARINE/BEACHES...MM
[top]
Area Forecast Discussion
National Weather Service Reno NV
312 AM PDT MON APR 25 2016
.SYNOPSIS...
Low pressure will move through western Nevada with a few showers
and brisk northwest winds expected this afternoon. 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...
An upper level low is currently centered across Nevada with areas of
light showers extending roughly from Fallon to just north of Pyramid
Lake. Current water vapor and IR satellite show drier air aloft
beginning to push across northern California which has diminished
shower activity and thinned cloud cover. Couple this with radar
trends and the latest HRRR simulations, do think that most of the
precipitation activity will remain across Pershing and Churchill
counties with only light shower activity along and west of the Hwy
395 corridor. As such, have expired the Winter Weather Advisory
across the Surprise Valley and northern Washoe County.
Brisk northwest winds will continue today with steady 15-25 mph
winds expected with gusts around 30-35 mph possible. This may
result in rough lake waters especially on Pyramid Lake and have a
Lake Wind Advisory in place today as a result. These northerly
winds may produce some terrain enhanced snow showers across Mono
County but all told snow showers should remain light with 1-2" of
snowfall possible mainly across eastern portions of Pershing and
Churchill counties.
Showers will diminish by this evening with a drier and quieter day
expected for Tuesday as we briefly see shortwave ridging aloft. This
will be followed by the next upper low which is expected to arrive
Tuesday night into Wednesday. This system will be a little warmer so
mainly expecting rain showers with isolated embedded thunderstorms
possible by Wednesday afternoon. Snow levels will remain around
6,000-6,500 feet during the afternoon so could see some snow and
rain mix at lake level. This system is also a quick moving trough
so that should also limit significant accumulations. Fuentes
.LONG TERM...Thursday through Sunday...
Low pressure hangs around on Thursday with moisture and instability.
Additional showers and a few thunderstorms remain through the day on
Thursday with peak instability in the afternoon, especially for
areas south of Interstate 80. Snow levels will remain around 6000-
7000 feet, although some stronger showers could bring snow levels
down to around 5000 feet at times. Low pressure moves out of the
area on Friday, with clearing skies and temperatures rising back up
into the upper 60s in western NV and upper 50s in the Sierra.
Beyond Friday, there is much uncertainty in the forecast as models
have been flip-flopping on potential of a shortwave dropping out of
Western Canada and into the Great Basin. This would potentially
bring a dry back-door cold front to the forecast area for the
weekend. Ensembles are also showing big differences in the forecast
as well. We didn`t make too much change in the forecast for the
weekend due to low forecaster confidence. Hoon
&&
.AVIATION...
A broad area of low pressure continues to affect the region with
moisture and shower activity. A few isolated to scattered showers
are possible this morning around KRNO/KCXP, although it does look
like the best potential will remain further east near KLOL-KNFL.
Periods of MVFR CIGS are likely through early this afternoon for the
area terminals, especially at KTRK and KTVL.
Gusty North-Northwest winds up to 25-30kts are expected through the
day, with gusts up to 40kts at KMMH. Low pressure moves out of the
area for Tuesday with lighter winds and clearing skies. Hoon
&&
.REV Watches/Warnings/Advisories...
NV...Lake Wind Advisory from 6 AM this morning to 8 PM PDT this
evening for Pyramid Lake in NVZ004.
CA...None.
&&
$$
For more information from the National Weather Service visit...
http://weather.gov/reno
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
738 AM EDT MON APR 25 2016
.AVIATION...
GENERALLY VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THE NEXT
24 HOURS. THE POSSIBLE EXCEPTION WILL BE SURROUNDING SHOWERS AND A
FEW THUNDERSTORMS DEVELOPING ALONG THE SEA BREEZE AFTER AROUND
19Z...AND CONTINUING THROUGH THE EARLY EVENING HOURS. AS SHOWERS
OR STORMS MOVE INTO THE VICINITY OF INDIVIDUAL TERMINALS...FLIGHT
CATEGORIES MAY BRIEFLY DROP TO MVFR/IFR.
&&
.PREV DISCUSSION... /ISSUED 355 AM EDT MON APR 25 2016/
SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A COMPLEX UPPER LEVEL
PATTERN OVER NORTH AMERICA THIS MORNING. THE MAIN FEATURE OF NOTE
INCLUDE A DEEP/SHARP TROUGH MOVING ASHORE OVER THE PACIFIC
COAST...WHICH THEN TRANSLATES INTO A POTENT UPPER LEVEL CLOSED LOW
SPINNING OVER THE HIGH PLAINS. THIS UPPER LOW IS SUPPORTING NUMEROUS
CLUSTER OF STRONG THUNDERSTORMS FROM THE CENTRAL PLAINS TO THE UPPER
MIDWEST. THE OTHER FEATURE OF NOTE...AND THE MOST IMPORTANT TO OUR
FORECAST THE NEXT 24 HOURS IS A SOUTHERN STREAM SHORTWAVE FEATURE
STEADILY PROGRESSING EASTWARD ACROSS THE GULF OF MEXICO TOWARD THE
FLORIDA PENINSULA. THIS ENERGY WILL HAVE SOME IMPACT ON OUR FORECAST
FOR LATER THIS AFTERNOON/EVENING...AND WE WILL DISCUSS THIS FEATURE
IN MORE DETAIL IN THE SHORT TERM DISCUSSION BELOW.
AT THE SURFACE...A LARGE SPRAWLING RIDGE OF HIGH PRESSURE IS LOCATED
ALONG THE EASTERN SEABOARD. THIS HIGH RIDGES ALL THE WAY SOUTH TO
COVER THE ENTIRE FLORIDA PENINSULA AND EASTERN GULF OF MEXICO. AS A
RESULT...THE GRADIENT IS FAIRLY RELAXED ACROSS THE REGION. THE WEAK
LOW LEVEL FLOW AND STRONG TERRESTRIAL HEATING WILL PROMOTE THE
DEVELOPMENT OF A HEALTHY SEA-BREEZE THIS AFTERNOON/EARLY EVENING.
SHORT TERM (TODAY THROUGH TUESDAY)...
AS MENTIONED ABOVE...WATCHING THE PROGRESS OF A WELL-DEFINED
SOUTHERN STREAM SHORTWAVE APPROACHING OVER THE GULF OF MEXICO. THE
MAIN SYNOPTIC FORCING/QVECTOR CONVERGENCE AHEAD OF THE TROUGH
AXIS ACTUALLY PASSES THROUGH OUR REGION AND OFF INTO THE ATLANTIC
FAIRLY EARLY TODAY. HOWEVER...WEAK HEIGHT FALLS CONTINUE INTO THE
AFTERNOON HOURS WITH MID-LEVEL LAPSE RATES IMPROVING/INCREASING TO
6-6.5C/KM. GIVEN THE LOWERED HEIGHT AND CERTAINLY LESS LARGE SCALE
SUPPRESSION THAN WAS SEEN ON SUNDAY...COMBINED WITH AN
INCREASINGLY FAVORABLE MOISTURE PROFILE...ANTICIPATE A MORE ACTIVE
CONVECTIVE SCENARIO THAN THE ISOLATED SHOWERS THAT FORMED ALONG
THE SEA-BREEZE LATE SUNDAY. SIMILAR TO SUNDAY...ANY
SHOWERS/ISOLATED STORMS WILL HOLD OFF UNTIL LATE IN THE
AFTERNOON...MEANING MOST OF THE DAYLIGHT HOURS TODAY WILL BE DRY.
TEMPERATURES CLIMB INTO THE 80S...AND WELL INTO THE 80S AWAY FROM
THE BEACHES. ONCE AGAIN...A WELL-DEFINED SEABREEZE CIRCULATION
WILL BECOMES ESTABLISHED BY 17-18Z. ONCE THE SEABREEZE BEGINS TO
PUSH INLAND...LOW LEVEL FOCUS AHEAD OF THE BOUNDARY WILL
COMPLIMENT THE IMPROVING THERMODYNAMICS ALOFT TO ALLOW A
SCATTERING OF SHOWERS TO DEVELOP ALONG THE I-75 CORRIDOR. GIVEN
THE FLOW PATTERN...MUCH IF NOT ALL THE CONVECTION WILL BE FOCUSED
ALONG THE FLORIDA WEST COAST BY LATE AFTERNOON. FOR NOW...WILL
KEEP RAIN CHANCES ALONG THIS CORRIDOR IN THE 30-50% RANGE AFTER
20Z...HOWEVER...NEIGHBORHOOD ENSEMBLE POPS FROM THE CONVECTION
ALLOWING GUIDANCE SUITE ARE ACTUALLY MORE AGGRESSIVE. SINCE
CONVECTION ALLOWING MODELS ARE OFTEN TOO AGGRESSIVE WITH
CONVECTION...ESPECIALLY THIS TIME OF YEAR...THE 30-50% POPS SEEM
A REASONABLE APPROACH. GIVEN THE MORE UNIFORM THERMODYNAMIC
ENVIRONMENT ACROSS THE AREA...WILL EXPECT SCT CONVECTION TO FIRE ALL
THE WAY UP THROUGH THE NATURE COAST TODAY AS WELL. FCST SOUNDING
PROFILES SUGGEST AN EQUILIBRIUM LEVEL AROUND 30,000 FEET AGL LATER
THIS AFTERNOON...PROVIDING A MUCH BETTER OPPORTUNITY TODAY FOR
UPDRAFTS TO REACH HEIGHTS CONDUCIVE FOR CHARGE SEPARATION AND
LIGHTING POTENTIAL. ALSO...THE COOLER MID-LEVEL TEMPS (-12C AT 500MB
FOR EXAMPLE) ALLOWS FOR DECENT CAPE PROFILES THROUGH THE -10C TO
-30C HAIL GROWTH ZONE... PER LATEST NAM/ARW/HRRR BUFKIT SOUNDINGS.
ANY STORMS THAT CAN SUPPORT A STRONGER AND/OR LONGER LASTING UPDRAFT
WILL HAVE THE POTENTIAL FOR SMALL HAIL. THE SCT CONVECTION WILL BE
SLOW MOVING TODAY...BUT SHOULD GENERALLY MIGRATE TOWARD THE COAST
AND OFFSHORE DURING THE EARLY/MID EVENING HOURS...BEFORE DISSIPATING.
THE SHORTWAVE AXIS MAKES A QUICK EXIT TO OUR EAST AND SOUTHEAST
TONIGHT...ALLOWING SUBTLE HEIGHT RISES OVER THE FLORIDA PENINSULA BY
SUNRISE TUESDAY. THIS PROCESS WILL CONTINUE THROUGHOUT TUESDAY AND
RESULT IN WELL DEFINED MID/UPPER RIDGING OVER OUR HEADS BY THE
SECOND HALF OF THE DAY. NEAR THE SURFACE...RIDGING WILL REMAIN IN
CONTROL FROM A HIGH CENTER LOCATED OVER THE WESTERN ATLANTIC. STRONG
TERRESTRIAL HEATING AND WEAK LOW LEVEL FLOW AGAIN ALLOWS SEA-
BREEZE FORMATION TO TURN WINDS ONSHORE AT THE BEACHES AFTER 17Z.
A SIMILAR FLOW PATTERN IN THE LOWER LEVELS TO PREVIOUS DAYS WILL
KEEP THE BEST CONVERGENCE ACROSS THE WESTERN SIDE OF THE FL
PENINSULA. CERTAINLY THE UPPER LEVELS THERMODYNAMICS ARE LESS
FAVORABLE BY TUESDAY AFTERNOON...AS THE RIDGING CONTINUES TO
BUILD...AND THEREFORE WILL SWING THE FORECAST BACK THE OTHER WAY
TOWARD MORE ISOLATED AND SHALLOW CONVECTION LATE TUESDAY
AFTERNOON/EVENING. HIGH TEMPERATURES TUESDAY IN THE MID/UPPER 80S
AWAY FROM THE BEACHES AND LOWER 80S AT THE IMMEDIATE COAST.
MID/LONG TERM (WEDNESDAY THROUGH NEXT SUNDAY)...
THE MID AND LONG TERM FORECAST PERIODS WILL FEATURE DRY WEATHER
AND ABOVE NORMAL TEMPERATURES FOR WEST CENTRAL AND SW FLORIDA.
SURFACE HIGH PRESSURE WILL REMAIN IN PLACE ACROSS THE WESTERN
ATLANTIC LEAVING US IN A PREDOMINANT E TO SE LOW-LEVEL FLOW FOR
MUCH OF THE WEEK AND INTO NEXT WEEKEND. THE ATMOSPHERE WILL REMAIN
FAIRLY DRY IN THE MID TO UPPER LEVELS AS MOST OF THE AVAILABLE
ATMOSPHERIC MOISTURE WILL REMAIN BELOW THE 700 MB LEVEL. THIS WILL
MAKE THE ENVIRONMENT VERY HOSTILE TO ANY SHOWERS THAT TRY TO
DEVELOP DURING THE AFTERNOON HOURS. ITS POSSIBLE THAT MAYBE A
STRAY SHOWER COULD DEVELOP WITH SEABREEZE INTERACTIONS BUT GIVEN
THE HOSTILE MID/UPPER LEVELS THEY WOULD BE FAIRLY SHALLOW SHOWERS
AND QPF WOULD BE VERY LOW. THAT BEING SAID MOST OF THE AREA CAN
EXPECT TO REMAIN DRY THIS WEEK AND INTO NEXT WEEKEND AND WILL KEEP
POPS BELOW 20 PERCENT AREA WIDE THROUGH THE FORECAST PERIOD.
DAILY AFTERNOON TEMPERATURES ARE EXPECTED TO TOP OUT IN THE MID TO
UPPER 80S...WITH SOME SPOTS REACHING 90 NOT OUT OF THE QUESTION
ACROSS THE INTERIOR. DAILY SEABREEZE DEVELOPMENT IN THE EARLY
AFTERNOON WILL HELP KEEP THE COASTAL REGIONS A TAD COOLER. OVERNIGHT
LOWS WILL BE ON THE MILD SIDE WITH MID TO UPPER 60S EXPECTED...LOWER
70S LIKELY NEAR THE IMMEDIATE COAST.
MARINE... THE PATTERN REMAINS STAGNANT THROUGH THE MIDDLE PORTION
OF THE WEEK...WITH HIGH PRESSURE OFF THE EASTERN SEABOARD
CONTINUES TO RIDGE BACK TO THE WEST OVER THE FLORIDA PENINSULA AND
EASTERN GULF OF MEXICO. THE PREDOMINANT LARGE SCALE FLOW AROUND
THIS RIDGE WILL BE FROM THE SOUTHEAST...HOWEVER THE GRADIENT IS
WEAK ENOUGH TO ALLOW WINDS TO TURN ONSHORE NEAR THE COAST EACH
AFTERNOON AND EVENING...BEFORE SWITCHING BACK TO THE SOUTHEAST BY
MIDNIGHT EACH NIGHT. WINDS AND SEAS WILL GENERALLY REMAIN BELOW
HEADLINE CRITERIA FOR SEVERAL DAYS TO COME. MARINERS SHOULD KEEP
AN EYE TO THE EAST LATER THIS AFTERNOON AS SCATTERED THUNDERSTORM
ARE EXPECTED TO DEVELOP ALONG THE I-75 CORRIDOR AFTER 3-4 PM
EDT...AND THEN SLOWLY MIGRATE OFFSHORE THROUGH THE EARLY EVENING
HOURS. STORMS WILL BE MUCH MORE ISOLATED IN NATURE FOR LATER
TUESDAY AND WEDNESDAY.
FIRE WEATHER...
HIGH PRESSURE AT THE SURFACE CONTINUE TO RIDGE OVER THE REGION FROM
THE WESTERN ATLANTIC THROUGH THE NEXT SEVERAL DAYS. SCATTERED STORMS
ARE ANTICIPATED TO DEVELOP ALONG THE I-75 CORRIDOR LATE THIS
AFTERNOON INTO THE EVENING HOUR BEFORE DISSIPATING AFTER SUNSET.
ONLY ISOLATED SHOWERS ARE EXPECTED LATE TUESDAY AND LATE WEDNESDAY
AFTERNOONS. RELATIVE HUMIDITY VALUES GENERALLY REMAIN ABOVE CRITICAL
LEVELS THROUGH THURSDAY. A FEW SPOTS MAY BRIEFLY REACH 35 PERCENT
ANY AFTERNOON...HOWEVER...EXTENDED DURATIONS OF CRITICAL RH ARE
UNLIKELY...AND WINDS WILL REMAIN BELOW CRITICAL LEVELS.
THEREFORE...NO RED FLAG CONDITIONS ARE ANTICIPATED THE NEXT SEVERAL
DAYS.
FOG POTENTIAL...ISOLATED POCKETS OF FOG ARE POSSIBLE INLAND EACH
NIGHT THROUGH THURSDAY...HOWEVER NO SIGNIFICANT AREAS OF DENSE FOG
OR VISIBILITY REDUCTIONS ARE ANTICIPATED.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 85 69 86 69 / 50 50 20 10
FMY 86 67 85 67 / 50 50 20 10
GIF 85 66 87 66 / 30 20 20 10
SRQ 80 69 81 67 / 30 30 10 10
BKV 86 64 84 63 / 40 40 20 10
SPG 84 70 84 71 / 40 40 20 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
AVIATION...18/FLEMING
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
1044 AM CDT MON APR 25 2016
.UPDATE...
1029 AM CDT
TEMPERATURES ARE OFF TO THE RACES THIS MORNING...ALREADY CLIMBING
INTO THE LOWER 70S BY 10 AM ACROSS NORTHERN IL/NORTHWEST IN...AND
WILL CONTINUE TO RISE TOWARDS 80 BY EARLY THIS AFTERNOON. VISIBLE
IMAGERY INDICATES MOSTLY SUNNY SKIES OVERHEAD...WITH THE EXCEPTION
OF A CHANNEL OF STRATUS OVER EXTREME NORTHWEST ILLINOIS STRETCHING
SOUTHWEST THROUGH CENTRAL MISSOURI. THIS AREA OF LOWER CLOUDS WAS
SLOWLY LIFTING NORTHEAST...AND EXPECTED TO STEADILY THIN AS IT
ENCOUNTERS A WELL MIXED ENVIRONMENT OVER NORTHERN IL.
THEN THE FOCUS TURNS TOWARDS THIS AFTERNOON AND CONVECTIVE CHANCES
AS WELL AS TIMING. WHILE SFC INSTABILITY IS POISED TO
INCREASE...ESPECIALLY WITHIN THE 0-3KM LAYER...IT IS AN
APPROACHING 50KT MID-LVL WIND FIELD THAT IS CONCERNING AS IT
MERGES WITH A CONVERGENT AIRMASS OVER NORTHEAST ILLINOIS BETWEEN
21-23Z...ADDING TO THE SHEAR WITHIN THE MID LEVELS. ONCE
CONVECTION DEVELOPS...SOME STEADY/QUICK GROWTH INTO A FEW
SUPERCELLS WILL BE POSSIBLE BETWEEN 22-23Z THEN BEGIN TO SHIFT
EAST/SOUTHEAST ACROSS FAR NORTHEAST ILLINOIS TURNING INTO NORTHERN
INDIANA BY EARLY THIS EVENING. MAIN HAZARDS WILL BE ISOLATED
DAMAGING HAIL AND WIND THREATS.
ALL OF THE ACTIVITY SHOULD BE ON A DOWNWARD TREND BY 2-4Z AS A
FRONTAL BOUNDARY DIVES SOUTH ALONG THE LAKE AND DIFFLUENT FLOW
PUSHES IN FROM THE WEST/NORTHWEST AND FLOW TURNS NORTHERLY
OVERNIGHT.
BEACHLER
&&
.SHORT TERM...
344 AM CDT
THROUGH WEDNESDAY...
PRIMARY CONCERNS IN THE SHORT TERM INCLUDE THE UNSEASONABLY WARM
TEMPS TODAY...THUNDERSTORM CHANCES LATE THIS AFTERNOON AND
EVENING...THEN LAKE ENHANCED COLD FRONT AND FREE FALL IN TEMPS
EARLY TUESDAY.
CONVECTION OVER IOWA IS QUICKLY MEETING ITS DEMISE AS IT
ENCOUNTERS DRIER MORE STABLE AIR MASS. SHORTWAVE ASSOCIATED WITH
THAT CONVECTION WILL MOVE ACROSS OUR AREA LATER THIS MORNING...BUT
SUSPECT IT WILL PASS THROUGH WITHOUT MUCH FANFARE OTHER THAN
CLOUDINESS. A 997MB SFC LOW OVER SD WILL MOVE EAST INTO SOUTHERN
WISCONSIN BY THIS EVENING BUT STEADILY WEAKEN ALONG THE WAY AS
STRONG SHORTWAVE AND ASSOCIATED CLOSED LOW RAPIDLY WEAKENS AND
SHEARS EASTWARD INTO THE UPPER GREAT LAKES REGION TONIGHT. DESPITE
SOME CLOUDINESS...STILL LOOKING FOR UNSEASONABLY WARM TEMPS TODAY
LIKELY TOPPING OUT IN THE LOWER 80S...EVEN ALONG THE LAKEFRONT AS
MODERATELY BRISK SOUTHERLY WINDS BRING THE WARMTH RIGHT UP TO THE
SHORELINE.
CONVECTION IS REALLY THE TRICKIEST PART OF THE FORECAST IN THE
NEAR TERM. AFTER SHORTWAVE PASSES THIS MORNING REALLY HARD TO FIND
ANY FEATURE TO SUPPORT LARGE SCALE ASCENT...IN FACT...IF ANYTHING
LOOK FOR SOME VERY SUBTLE MID LEVEL HEIGHT RISES THIS
AFTERNOON/EVENING AS UPPER LOW QUICKLY FILLS. DESPITE THE LIMITED
TO NON-EXISTENT SUPPORT ALOFT...MAJORITY OF CONVECTIVE ALLOWING
MODELS (CAMS) BREAK OUT CONVECTION THIS AFTERNOON ALONG WEAK
ADVANCING COLD FRONT. SHOULD SEE MLCAPE VALUES APPROACHING 1000
J/KG IN ADVANCE OF THE FRONT AS DEWPOINTS POOL IN THE MID 50S TO
PERHAPS NEAR 60 ALONG THE FRONT AND SFC TEMPS WARM INTO THE LOW
80S. EVENING SOUNDINGS TO OUR WEST SHOW LARGE POOL OF STEEP MID
LEVEL LAPSE RATES WHICH AS FORECAST TO ADVECT EASTWARD INTO OUR
AREA THIS AFTERNOON WHICH SHOULD HELP WITH INSTABILITY...THOUGH IT
DOES LEAD TO QUESTIONS REGARDING WHETHER A WEAK CAPPING INVERSION
COULD DEVELOP AT BASE OF THIS ELEVATED MIXED LAYER.
CERTAINLY CONCERNS ARE THERE WITH SUCH WEAK FORCING AND POTENTIAL
CAPPING...BUT GIVEN THE UNANIMITY OF THE CAMS IN FIRING AT LEAST A
BROKEN LINE OF STORMS ALONG THE WEAK FRONT/PRE-FRONTAL TROUGH TO
OUR WEST THIS AFTERNOON...SPREADING EAST ACROSS OUR CWA VERY LATE
THIS AFTERNOON INTO EARLY THIS EVENING...FELT SOMEWHAT COMFORTABLE
HOLDING ONTO LOW END LIKELY POPS TONIGHT. ASSUMING STORMS DO
INDEED MATERIALIZE AS FORECAST...GUIDANCE SUGGESTS A 40-50KT 500MB
JET STREAK WILL MOVE INTO THE AREA THIS EVENING...WHICH SHOULD
RESULT IN SUFFICIENTLY STRONG SHEAR TO SUPPORT A THREAT OF LARGE
HAIL/DAMAGING WIND THREAT WITH ANY STORMS. BOTH SHEAR AND
INSTABILITY ARE FORECAST TO BE WITHIN THE RANGE TO SUPPORT
SUPERCELLS...WHICH WOULD ONLY ENHANCE THE HAIL THREAT. LARGE T/TD
SPREADS AND WEAKER LOW LEVEL SHEAR SHOULD LIMIT THE TORNADO
POTENTIAL.
STORMS SHOULD MOVE OUT OF THE AREA BETWEEN 06-09Z TUESDAY...THOUGH
IT WILL REMAIN MILD MUCH OF THE NIGHT TONIGHT. MODELS HAVE
CONTINUED TO TREND SLOWER WITH THE SECONDARY LAKE ENHANCED FRONT
WHICH IS POISED TO BRING A QUICK AND DRAMATIC END TO OUR SUMMER-
LIKE WARMTH. LATEST MODE RUNS NOW HAVE THE FRONT PLOWING IN OFF
THE LAKE EARLY TUESDAY MORNING WITH TEMPS DROPPING INTO THE 50S
BEHIND THE FRONT...EXCEPT INTO THE 40S NEAR THE LAKE. FRONT SHOULD
MOVE THROUGH SOUTHERN CWA DURING THE AFTERNOON ALLOWING FOR TEMPS
TO WARM INTO THE 70S AHEAD OF THE FRONT BEFORE TEMPS CRASH BEHIND
THE FRONT LATE.
IZZI
&&
.LONG TERM...
344 AM CDT
WEDNESDAY NIGHT THROUGH MONDAY...
ANOTHER STRONG NEGATIVELY TILTED SHORTWAVE WILL BRING SEVERE
WEATHER TO THE PLAINS TUESDAY AFTERNOON THEN BEGIN TO WEAKEN AS IT
MOVES TOWARD THE MIDWEST WEDNESDAY. NORTHEAST LOW LEVEL FLOW
SHOULD PROVIDE A STEADY FEED OF DRY AIR WHICH SHOULD HELP DELAY
THE ONSET OF THE PRECIP IN OUR CWA...ESPECIALLY THE FARTHER NORTH
AND EAST YOU GET. HAVE DELAYED THE ONSET OF THE HIGHER POPS FROM
PREVIOUS FORECAST. REALLY NOT LOOKING LIKE MUCH OF A THUNDERSTORM
THREAT THIS FAR NORTH AS WEAK LAPSE AND QUICKLY WEAKENING SYSTEM
KEEPS LOW LEVEL JET AND POTENTIAL FOR LLJ DRIVEN STORMS FAIRLY
LOW. STILL LOOKS LIKE A DECENT RAIN EVENT WEDNESDAY INTO WEDNESDAY
NIGHT. DRIER AND SEASONABLY CHILLY CONDITIONS ARE EXPECTED IN THE
WAKE OF THIS SYSTEM LATER THURSDAY INTO FRIDAY BEFORE WE RINSE AND
REPEAT WITH ANOTHER STRONG NEGATIVELY TILTED CLOSED LOW MOVING
INTO THE PLAINS BEFORE SLOWLY WEAKENING AS IT WOBBLES INTO OUR
AREA NEXT WEEKEND WITH RAIN CHANCES RETURNING. ONCE FRONT MOVES
THROUGH TOMORROW MORNING LOOK FOR CHILLY WINDS OFF THE LAKE TO
LOCK IN FOR THE REST OF THE WEEK AND PROBABLY INTO THE WEEKEND AS
WELL.
IZZI
&&
.AVIATION...
FOR THE 12Z TAFS...
THE NEXT LOW PRESSURE SYSTEM IS CURRENTLY OVER THE WESTERN MN/IA
STATE LINE AND IT WILL CONTINUE TO WEAKEN AS IT PASSES OVER THE
REGION TONIGHT. VFR CIGS ARE EXPECTED WITH SSW WINDS GUSTING TO
20-25 KT ESPECIALLY AFTER 18Z. GUIDANCE MEMBERS ARE STILL
SUGGESTING CONVECTION WILL FIRE AHEAD OF THE COLD FRONT THIS
EVENING...BUT THINKING THE MODELS MAY BE TOO FAST WITH THE FRONT
AND ASSOCIATED CONVECTION. HOWEVER...DO NOT HAVE ENOUGH CONFIDENCE
TO ADJUST TIMING AND COVERAGE OF CONVECTION SO LEFT WELL ENOUGH
ALONE FOR NOW. IF CONVECTION FIRES LATE THIS AFTN/EARLY THIS
EVENING COULD SEE SOME STORMS PRODUCE WIND GUSTS UP TO 60 MPH AND
HAIL UP TO HALF DOLLAR SIZE. IF THE FRONT AND ASSOICATED STORMS
DEVELOP LATER...MAY NOT SEE ANY THUNDERSTORMS AT ALL.
WINDS BECOME NORTHWEST AND CLOUDS BRIEFLY SCATTER OUT BEHIND THE
FRONT. WINDS CONTINUE TO VEER INTO TUESDAY MORNING WITH NORTHEAST
WINDS IN EXCESS OF 10 KT. THINKING AN IFR MARINE STRATUS DECK
WILL PUSH ON SHORE.
CONFIDENCE...MEDIUM CONFIDENCE IN THUNDERSTORM
OCCURRENCE...MEDIUM-LOW CONFIDENCE IN THUNDERSTORM TIMING. HIGH
CONFIDENCE IN WINDS THROUGH THE PERIOD. LOW CONFIDENCE IN IFR CIGS
TUESDAY MORNING.
JEE
&&
.MARINE...
304 AM CDT
HEADLINES...REPLACED THE GALE WATCH WITH A GALE WARNING FOR LATE
THIS AFTERNOON INTO EARLY TUESDAY MORNING. ALSO ISSUED A SMALL
CRAFT ADVISORY FOR HAZARDOUS WAVES TUESDAY MORNING INTO WEDNESDAY
EVENING FOR THE IL NSH AND TUESDAY AFTN INTO WEDNESDAY AFTN FOR THE
INDIANA NSH WATERS.
A COLD FRONT IS OVER CENTRAL LAKE MICHIGAN WITH NE WINDS NORTH OF
THE FRONT AND SOUTHEAST WINDS TO THE SOUTH. WINDS WILL INCREASE TO
GALE FORCE OVER THE NORTHERN END LATE THIS AFTN WHILE WINDS ON THE
SOUTH HALF WILL BECOME SOUTHWEST THIS EVENING. THE FRONT WILL SHIFT
SOUTH AS THE WEAKENING LOW PASSES OVER THE SOUTHERN END OF THE LAKE
TONIGHT. WINDS BECOME NORTHEAST LEADING TO HAZARDOUS WAVES IN THE
NSH WATERS INTO WEDNESDAY EVENING. ANOTHER LOW MOVES OVER THE
PLAINS WEDNESDAY AND PASSES SOUTH OF THE LAKE THURSDAY. NORTHEAST TO
EAST WINDS TO 25 KT CONTINUE THROUGH THURSDAY AFTERNOON PROBABLY
LEADING TO ANOTHER PERIOD OF HAZARDOUS WAVES FOR AT LEAST THE IL NSH
WATERS. THE SOUTHERN END OF HIGH PRESSURE CENTERED OVER HUDSON BAY
ROTATES OVER THE LAKE LATE THIS WEEK WITH WEAK NORTH TO NORTHEAST
WINDS. ANOTHER LOW IS PROGGED TO SLOWLY SHIFT EAST FROM THE PLAINS
TO OVER CENTRAL IL AND INDIANA LAKE EARLY NEXT WEEK. THIS WILL
RESULT IN STRENGTHENING NORTHEAST WINDS.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...10 AM TUESDAY TO
10 PM WEDNESDAY.
SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...4 PM TUESDAY TO 4
PM WEDNESDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1014 AM CDT MON APR 25 2016
.UPDATE...
Issued at 1014 AM CDT Mon Apr 25 2016
Early morning scattered clouds have been thinning out and moving
east out of the area, with mostly sunny conditions at midday. Wind
gusts starting to reach the 25-30 mph range in several areas as
the low level inversion seen on the morning sounding mixes out.
Temperatures have already reached the 70-75 degree range across
the CWA. While clouds should start to increase later today,
CAPE`s expected to reach over 1500 J/kg by mid afternoon over west
central Illinois, helping to fuel some scattered thunderstorms.
Have done some tweaking to the timing of the convection, starting
the PoP`s northwest of the Illinois River around 2-3 pm and
bringing them about as far as Springfield-Rantoul by late
afternoon. Latest HRRR and the evening run of the NSSL 1km ARW do
suggest some scattered convection more in the Decatur-Champaign
area late afternoon, so have maintained the slight chance PoP`s in
that area but limited them to late afternoon. Greatest convection
still expected more across northern Illinois, shifting southward
as the boundary moves into central Illinois/Indiana tonight.
Northern parts of the CWA should pretty much be dry by midnight,
and have removed the post-midnight PoP`s in that area.
&&
.SHORT TERM...(Today)
ISSUED AT 333 AM CDT Mon Apr 25 2016
Storm system over eastern South Dakota as of 300 am is expected to
track east along a stalled frontal boundary over northern Iowa east
through southern Wisconsin later today. A cold front located from
the low over eastern South Dakota southward through eastern Nebraska
will track slowly east today and not get into our area until first
thing Tuesday morning. Surface dew points in the mid to upper 50s
were noted just east of the cold front and as the boundary shifts
east today, so will the moist axis into our area this afternoon.
As was advertised with most model data, the storms that occurred
last night in Iowa have dissipated with the latest surface analysis
indicating a weak boundary/remnant outflow boundary over east
central Iowa. Most of the high res reflectivity simulations off the
4km NAM along with the WRF-ARW and NMM indicate redevelopment in
west-central Illinois later this afternoon. Surface temperatures in
the lower 80s combined with dew points in the upper 50s will yield
ML capes of around 1800 in a few areas along and west of the
Illinois River later this afternoon. That combined with rather steep
mid level lapse rates and 0-6km shear values of around 40 kts will
bring the threat for scattered thunderstorms after 300 pm, some of
which may produce strong winds and large hail, roughly along and
west of a Springfield to Bloomington line.
.LONG TERM...(Tonight through Sunday)
ISSUED AT 333 AM CDT Mon Apr 25 2016
After another warm day, with showers and thunderstorms chances
through the afternoon and into the evening hours, a series of
weather systems will bring precip for most of this week. The first
wave has slowed on approach overall, delaying the onset of precip.
Also, models are having some consistency issues with the extent of
the southerly progression of the front before the next wave moves
into the Midwest and enhances the precip/storms for Tuesday night
and into Wednesday. Much of ILX sits in an area with limited severe
weather potential partially due to timing of the system late Tuesday
in the overnight hours. At any rate, the deep low over the southern
Plains ejects out and into the region, spreading best chances for
precipitation Wednesday and Wednesday night. Models still limiting
the progression of the warm front, keeping temperatures not quite as
warm for Tue/Wed ahead of the advancing storm center. By late
Thursday, the winds become more northerly and drier air slowly tries
to build back in for a brief break Thu night through later Friday.
The break looks to be short lived again as another wave moves out of
the long wave trof over the SW and into the region, bringing precip
back for next weekend. Overall, an active pattern, with more wet
than dry.
&&
.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
Issued at 612 AM CDT Mon Apr 25 2016
VFR conditions are expected this forecast period. Thunderstorms
that occurred to our west last evening have dissipated as they
approached the Mississippi River early this morning. There were
some scattered mid and high clouds that were pushing into the area
from the storms that occurred last evening. Latest sounding data
indicates some higher based cumulus should develop late this
morning with bases in the 4000-5000 foot range. In addition, a
rather gusty south to southwest wind of 15 to 20 kts is expected
later this morning into the afternoon hours with gusts around 25
kts possible. As a frontal boundary slow approaches the area late
tonight and tonight, scattered convection will be possible, but at
this time, it appears coverage will be too limited to include much
more than VCTS. Southwest winds of 10 to 15 kts can be expected
after sunset this evening.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...Smith
LONG TERM...HJS
AVIATION...Smith
AREA FORECAST DISCUSSION...UPDATED
NWS QUAD CITIES IA IL
1033 AM CDT MON APR 25 2016
.UPDATE...
ISSUED AT 1029 AM CDT MON APR 25 2016
STILL ON TRACK FOR STRONG TO SEVERE STORMS THIS AFTERNOON AS H5
AND H3 JET APPROACHES THE AREA. THIS WITH A SURGE IN THE SFC
BOUNDARY WILL LEAD TO CONVERGENCE AT THE SFC AND STORM INITIATION
AROUND 19Z. BEST CHANCES FOR SEVERE WEATHER WILL BE IN OUR
ILLINOIS ZONES AS STORMS MATURE. DEEP LAYER SHEAR AND HIRES MODELS
SUGGEST ISOLATED SUPERCELLULAR STRICTURES WITH LARGE HAIL BEING
THE MAIN THREAT. MAIN LIMITING FACTOR WILL BE STORM COVERAGE AS
SOME CAMS DO NOT PRODUCE ANY STORMS. THAT SAID ANYTHING THAT DOES
DEVELOP WILL HAVE THE CHANCE TO BECOME SEVERE. HAVE UPDATED POP
GRIDS WITH CURRENT TIMING AND CHANGED THE SKY GRIDS AS WELL. NO
OTHER CHANGES ARE EXPECTED AT THIS TIME.
&&
.SYNOPSIS...
ISSUED AT 315 AM CDT MON APR 25 2016
LOW PRESSURE WAS LOCATED IN EXTREME EASTERN SD WITH A WARM FRONT
INTO SOUTHERN WI AND A COLD FRONT EXTENDING FROM THE LOW INTO
EXTREME EASTERN NEB AND THEN TO SW KS. LINE OF THUNDERSTORMS THAT
WAS IN CENTRAL IA EARLIER IN THE NIGHT HAS RAPIDLY DECAYED THE
PAST COUPLE OF HOURS TO ONLY A FEW SHOWERS. THIS IS DUE TO A MUCH
MORE STABLE AIRMASS OVER THE DVN CWA AND LACK OF SHEAR.
TEMPERATURES WERE MILD EARLY THIS MORNING AS EXPECTED WITH A
STEADY SOUTH WIND AND CLOUD COVER. 3 AM TEMPERATURES WERE MAINLY
IN THE LOWER TO MID 60S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CDT MON APR 25 2016
FORECAST FOCUS ON THE POTENTIAL FOR ISOLATED STRONG OR SEVERE
THUNDERSTORMS LATER TODAY.
TODAY...WHAT FEW SHOWERS THERE ARE EARLY THIS MORNING WILL
CONTINUE TO FADE AWAY LEAVING THE MORNING HOURS (AFTER 6 AM) DRY.
THEN THE FOCUS WILL BE ON IF ANY CONVECTION CAN ERUPT LATER THIS
AFTERNOON AND EVENING. LOW PRESSURE WILL TRACK ACROSS SOUTHERN MN
AND BE NEAR LA CROSSE WI BY EVENING. A WEAK COLD FRONT WILL DRAG
SOUTHEAST INTO THE DVN CWA THIS AFTERNOON. AHEAD OF THE FRONT
TEMPERATURES SHOULD WARM INTO THE UPPER 70S TO LOWER 80S. WITH
DEWPOINTS IN THE MID 50S TO AROUND 60 THIS SHOULD YIELD MUCAPES OF
ABOUT 2000 J/KG AND MLCAPE TO 1000 J/KG. A 50 KNOT MID LEVEL WIND
MAX WILL APPROACH THE AREA AT PEAK HEATING WITH MODERATE DEEP
LAYER SHEAR OF 40 KNOTS. ANY STORMS DEVELOPING IN THIS ENVIRONMENT
SHOULD BE ABLE TO PRODUCE LARGE HAIL AND DAMAGING WINDS.
HOWEVER...THE BIG PROBLEM IS THE LACK OF SUFFICIENT CONVERGENCE
NEAR THE FRONT AS THE WINDS VEER UNIDIRECTIONAL FROM THE SOUTHWEST.
THE HRRR KEEPS THE CONVECTION IN WI CLOSER TO THE SURFACE LOW AND
BETTER FORCING WHILE THE SPC 4.0 KM WRF-NMM FIRES UP CONVECTION
EAST OF THE MS RIVER NOT UNTIL THIS EVENING. THEREFORE...HAVE
KEPT MENTION OF CHANCE POPS IN THE 20-40 PERCENT RANGE AND MAINLY
ALONG AND EAST OF THE MS RIVER LATER THIS AFTERNOON AND EVENING...
AHEAD OF THE FRONT. SPC DOES HAVE A SLIGHT RISK EAST OF THE MS RIVER.
AT THIS TIME WILL KEEP COVERAGE OF THE STORMS TO ISOLATED TO
SCATTERED BUT THE POTENTIAL IS THERE FOR A DRY FROPA...AND LET DAY
SHIFT MONITOR TRENDS.
TONIGHT...ASSUMING CONVECTION FORMS LATER THIS AFTERNOON AND
EVENING THE FRONT WILL HAVE PUSHED EAST OF THE DVN CWA BY LATE
EVENING ENDING ANY RAIN CHANCES. WEST WINDS SHOULD BRING SOMEWHAT
DRIER AIR INTO THE CWA SO LOWS TONIGHT WILL BE COOLER...IN THE 50S.
SKIES WILL BECOME CLEAR OR PARTLY CLOUDY BEHIND THE FRONT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 315 AM CDT MON APR 25 2016
THE FORECAST OF VERY ACTIVE SYNOPTIC PROGRESSIVE LOW PRESSURE
SYSTEMS REMAINS FORECAST BY ALL GLOBAL MODELS TONIGHT FOR THE
EXTENDED FORECAST. THE TREND THAT THESE SYSTEMS WILL PASS JUST SOUTH
OF OUR CWA...OR THROUGH OUR SOUTHERN CWA CONTINUES TO SUGGEST
EXTENDED PERIODS OF NEAR 100 PERCENT POPS WILL BE REQUIRED FOR LATE
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT AND POSSIBLY THURSDAY. ANOTHER
SYSTEM ON THE HEELS OF THE DEPARTING THURSDAY LOW APPEARS SIMILAR
WITH WIDESPREAD STRATIFORM RAIN/EMBEDDED THUNDER FOR LATE FRIDAY
NIGHT THROUGH THE ENTIRE UPCOMING WEEKEND AND POSSIBLY EARLY WEEK
AHEAD. THAT SYSTEM AS THE MOMENT IS SUGGESTED TO END THE PROGRESSIVE
NATURE OF THE SYNOPTIC FLOW...AND CUT OFF INTO A BROAD UPPER LOW
OVER THE EASTERN HALF OF THE CONUS. THIS IS THE CASE IN BOTH THE GFS
AND EC 00Z RUNS. IN ANY CASE...RAIN...AND PLENTY OF IT....IS
FORECAST THIS UPCOMING WEEK...WITH SOME BOUTS OF EMBEDDED THUNDER
LIKELY AS WELL DURING PERIODS OF STRONG WARM ADVECTION ALOFT.
AT THE TIME...WHILE THE WEEK LONG PERIOD OFFERS THE POTENTIAL FOR
WIDESPREAD 1 TO 2 INCHES OF RAIN...WITH SOME AREAS POSSIBLY SEEING
MORE IN MESOSCALE BANDS OF ACTIVITY. THE RAINFALL RATES OVER ALL
SEEM TO OFFER A SOMEWHAT MORE BENIGN FLASH FLOODING FORECAST...AND
A SLOWLY EVOLVING RIVER RISE POTENTIAL.
TEMPERATURES TUESDAY UNDER SHORT TERM HIGH PRESSURE AND LITTLE COLD
ADVECTION SHOULD TOP OUT WELL INTO THE 70S...MAKING FOR A CERTAIN
CANDIDATE FOR THE MOST PLEASANT DAY THIS WEEK. ONCE RAIN AND CLOUDS
ARRIVE TUESDAY NIGHT...THE NEXT DRY DAY WITH ANY PREDICTABILITY MAY
BE FRIDAY. WEDNESDAY THROUGH THURSDAY WILL SEE FAR COLDER
TEMPERATURES AS IN THE LOWER 50S TO LOWER 60S FROM NORTH TO
SOUTH...AS RAIN COOLED AIR PERSISTS NORTH OF THE WARM FRONT. AT THIS
TIME...IT APPEARS THE WET AND CLOUDY WEATHER WILL KEEP US WELL BELOW
NORMAL WELL INTO NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 657 AM CDT MON APR 25 2016
MAINLY VFR CONDS THROUGH THIS TAF CYCLE. SOUTH WINDS AROUND 10
KNOTS EARLY THIS MORNING WILL VEER SOUTHWEST AND INCREASE TO 15 TO
25 KNOTS LATER THIS MORNING AND AFTERNOON. A WEAK COLD FRONT WILL
PUSH ACROSS EASTERN IA LATE THIS AFTERNOON WITH THE POTENTIAL FOR
ISOLATED TO SCATTERED THUNDERSTORMS ALONG THE FRONT. DUE TO WEAK
CONVERGENCE ALONG THE FRONT THERE IS ALSO THE POSSIBILITY OF A DRY
FROPA SO CONFIDENCE IS RATHER LOW ON COVERAGE OF THUNDERSTORMS.
THEREFORE...WILL MAINTAIN THE VCTS AT KBRL/KDBQ/KMLI. THE FRONT
WILL PUSH INTO IL EARLY THIS EVENING ENDING ANY THREAT OF RAIN.
WINDS WILL BECOME WEST BEHIND THE FRONT AT LESS THAN 10 KNOTS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...GIBBS
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...ERVIN
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
658 AM CDT MON APR 25 2016
...AVIATION UPDATE...
.SYNOPSIS...
ISSUED AT 315 AM CDT MON APR 25 2016
LOW PRESSURE WAS LOCATED IN EXTREME EASTERN SD WITH A WARM FRONT
INTO SOUTHERN WI AND A COLD FRONT EXTENDING FROM THE LOW INTO
EXTREME EASTERN NEB AND THEN TO SW KS. LINE OF THUNDERSTORMS THAT
WAS IN CENTRAL IA EARLIER IN THE NIGHT HAS RAPIDLY DECAYED THE
PAST COUPLE OF HOURS TO ONLY A FEW SHOWERS. THIS IS DUE TO A MUCH
MORE STABLE AIRMASS OVER THE DVN CWA AND LACK OF SHEAR.
TEMPERATURES WERE MILD EARLY THIS MORNING AS EXPECTED WITH A
STEADY SOUTH WIND AND CLOUD COVER. 3 AM TEMPERATURES WERE MAINLY
IN THE LOWER TO MID 60S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CDT MON APR 25 2016
FORECAST FOCUS ON THE POTENTIAL FOR ISOLATED STRONG OR SEVERE
THUNDERSTORMS LATER TODAY.
TODAY...WHAT FEW SHOWERS THERE ARE EARLY THIS MORNING WILL
CONTINUE TO FADE AWAY LEAVING THE MORNING HOURS (AFTER 6 AM) DRY.
THEN THE FOCUS WILL BE ON IF ANY CONVECTION CAN ERUPT LATER THIS
AFTERNOON AND EVENING. LOW PRESSURE WILL TRACK ACROSS SOUTHERN MN
AND BE NEAR LA CROSSE WI BY EVENING. A WEAK COLD FRONT WILL DRAG
SOUTHEAST INTO THE DVN CWA THIS AFTERNOON. AHEAD OF THE FRONT
TEMPERATURES SHOULD WARM INTO THE UPPER 70S TO LOWER 80S. WITH
DEWPOINTS IN THE MID 50S TO AROUND 60 THIS SHOULD YIELD MUCAPES OF
ABOUT 2000 J/KG AND MLCAPE TO 1000 J/KG. A 50 KNOT MID LEVEL WIND
MAX WILL APPROACH THE AREA AT PEAK HEATING WITH MODERATE DEEP
LAYER SHEAR OF 40 KNOTS. ANY STORMS DEVELOPING IN THIS ENVIRONMENT
SHOULD BE ABLE TO PRODUCE LARGE HAIL AND DAMAGING WINDS.
HOWEVER...THE BIG PROBLEM IS THE LACK OF SUFFICIENT CONVERGENCE
NEAR THE FRONT AS THE WINDS VEER UNIDIRECTIONAL FROM THE SOUTHWEST.
THE HRRR KEEPS THE CONVECTION IN WI CLOSER TO THE SURFACE LOW AND
BETTER FORCING WHILE THE SPC 4.0 KM WRF-NMM FIRES UP CONVECTION
EAST OF THE MS RIVER NOT UNTIL THIS EVENING. THEREFORE...HAVE
KEPT MENTION OF CHANCE POPS IN THE 20-40 PERCENT RANGE AND MAINLY
ALONG AND EAST OF THE MS RIVER LATER THIS AFTERNOON AND EVENING...
AHEAD OF THE FRONT. SPC DOES HAVE A SLIGHT RISK EAST OF THE MS RIVER.
AT THIS TIME WILL KEEP COVERAGE OF THE STORMS TO ISOLATED TO
SCATTERED BUT THE POTENTIAL IS THERE FOR A DRY FROPA...AND LET DAY
SHIFT MONITOR TRENDS.
TONIGHT...ASSUMING CONVECTION FORMS LATER THIS AFTERNOON AND
EVENING THE FRONT WILL HAVE PUSHED EAST OF THE DVN CWA BY LATE
EVENING ENDING ANY RAIN CHANCES. WEST WINDS SHOULD BRING SOMEWHAT
DRIER AIR INTO THE CWA SO LOWS TONIGHT WILL BE COOLER...IN THE 50S.
SKIES WILL BECOME CLEAR OR PARTLY CLOUDY BEHIND THE FRONT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 315 AM CDT MON APR 25 2016
THE FORECAST OF VERY ACTIVE SYNOPTIC PROGRESSIVE LOW PRESSURE
SYSTEMS REMAINS FORECAST BY ALL GLOBAL MODELS TONIGHT FOR THE
EXTENDED FORECAST. THE TREND THAT THESE SYSTEMS WILL PASS JUST SOUTH
OF OUR CWA...OR THROUGH OUR SOUTHERN CWA CONTINUES TO SUGGEST
EXTENDED PERIODS OF NEAR 100 PERCENT POPS WILL BE REQUIRED FOR LATE
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT AND POSSIBLY THURSDAY. ANOTHER
SYSTEM ON THE HEELS OF THE DEPARTING THURSDAY LOW APPEARS SIMILAR
WITH WIDESPREAD STRATIFORM RAIN/EMBEDDED THUNDER FOR LATE FRIDAY
NIGHT THROUGH THE ENTIRE UPCOMING WEEKEND AND POSSIBLY EARLY WEEK
AHEAD. THAT SYSTEM AS THE MOMENT IS SUGGESTED TO END THE PROGRESSIVE
NATURE OF THE SYNOPTIC FLOW...AND CUT OFF INTO A BROAD UPPER LOW
OVER THE EASTERN HALF OF THE CONUS. THIS IS THE CASE IN BOTH THE GFS
AND EC 00Z RUNS. IN ANY CASE...RAIN...AND PLENTY OF IT....IS
FORECAST THIS UPCOMING WEEK...WITH SOME BOUTS OF EMBEDDED THUNDER
LIKELY AS WELL DURING PERIODS OF STRONG WARM ADVECTION ALOFT.
AT THE TIME...WHILE THE WEEK LONG PERIOD OFFERS THE POTENTIAL FOR
WIDESPREAD 1 TO 2 INCHES OF RAIN...WITH SOME AREAS POSSIBLY SEEING
MORE IN MESOSCALE BANDS OF ACTIVITY. THE RAINFALL RATES OVER ALL
SEEM TO OFFER A SOMEWHAT MORE BENIGN FLASH FLOODING FORECAST...AND
A SLOWLY EVOLVING RIVER RISE POTENTIAL.
TEMPERATURES TUESDAY UNDER SHORT TERM HIGH PRESSURE AND LITTLE COLD
ADVECTION SHOULD TOP OUT WELL INTO THE 70S...MAKING FOR A CERTAIN
CANDIDATE FOR THE MOST PLEASANT DAY THIS WEEK. ONCE RAIN AND CLOUDS
ARRIVE TUESDAY NIGHT...THE NEXT DRY DAY WITH ANY PREDICTABILITY MAY
BE FRIDAY. WEDNESDAY THROUGH THURSDAY WILL SEE FAR COLDER
TEMPERATURES AS IN THE LOWER 50S TO LOWER 60S FROM NORTH TO
SOUTH...AS RAIN COOLED AIR PERSISTS NORTH OF THE WARM FRONT. AT THIS
TIME...IT APPEARS THE WET AND CLOUDY WEATHER WILL KEEP US WELL BELOW
NORMAL WELL INTO NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 657 AM CDT MON APR 25 2016
MAINLY VFR CONDS THROUGH THIS TAF CYCLE. SOUTH WINDS AROUND 10
KNOTS EARLY THIS MORNING WILL VEER SOUTHWEST AND INCREASE TO 15 TO
25 KNOTS LATER THIS MORNING AND AFTERNOON. A WEAK COLD FRONT WILL
PUSH ACROSS EASTERN IA LATE THIS AFTERNOON WITH THE POTENTIAL FOR
ISOLATED TO SCATTERED THUNDERSTORMS ALONG THE FRONT. DUE TO WEAK
CONVERGENCE ALONG THE FRONT THERE IS ALSO THE POSSIBILITY OF A DRY
FROPA SO CONFIDENCE IS RATHER LOW ON COVERAGE OF THUNDERSTORMS.
THEREFORE...WILL MAINTAIN THE VCTS AT KBRL/KDBQ/KMLI. THE FRONT
WILL PUSH INTO IL EARLY THIS EVENING ENDING ANY THREAT OF RAIN.
WINDS WILL BECOME WEST BEHIND THE FRONT AT LESS THAN 10 KNOTS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...ERVIN
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
745 AM EDT MON APR 25 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 422 AM EDT MON APR 25 2016
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CONFLUENT NW FLOW
ALF INTO THE UPR LKS BTWN NRN BRANCH CLOSED LO OVER NRN QUEBEC AND A
SRN BRANCH SHRTWV OVER THE WRN GREAT LKS AHEAD OF STRONG SHRTWV
MOVING SLOWLY ENEWD THRU THE NCENTRAL PLAINS. ALTHOUGH MOISTER
AIR...WITH 00Z PWATS AS HI AS 1.16 INCH AT MPX /ALMOST 250 PCT OF
NORMAL/ AND 0.92 INCH AT GRB /190 PCT OF NORMAL/...HAS PUSHED
FARTHER N AHEAD OF THIS SHRTWV AND SFC/H85 LO OVER ERN SDAKOTA...
DRIER AIR ON THE SRN FLANK OF BONE DRY AIRMASS IN ONTARIO /WHERE 00Z
PWAT AT YPL WAS ONLY 0.12 INCH/ MAINTAINED BY PROXIMITY OF THE
CONFLUENCE ZN BTWN THE BRANCHES SLOWED THE ARRIVAL OF HEAVIER RA
THAT HAS BEEN FCST RECENTLY. HOWEVER...LATEST RADAR IMAGERY SHOWS A
BAND OF RA N OF A NEARLY STNRY H85 WARM FNT STRETCHING FM CENTRAL MN
ACRS NCENTRAL WI IS PUSHING NE THRU UPR MI. UPR DVGC IN RRQ OF 120KT
H3 JET MAX OVER SW QUEBEC AS WELL AS SHARP H85-7 FGEN N OF THE ARPCHG
WARM FNT APPEAR TO BE SGNFT FORCING MECHANISMS. BUT THIS BAND IS
RATHER NARROW...WITH DRY SLOTTING IN ADVANCE OF THE APRCHG SHRTWV
CAUSING A SHARP SRN EDGE TO THIS BAND OF HEAVIER RA THAT IS ALREADY
PUSHING N ACRS THE WI BORDER.
MAIN FCST CONCERNS THRU TNGT FOCUS ON POPS/QPF TODAY AHEAD OF SLOWLY
APRCHG SHRTWV AND THEN DRYING TRENDS/POTENTIAL FOR SOME SN TNGT AS
LARGE SCALE SUBSIDENCE/SOMEWHAT COLDER AIR FOLLOW IN THE WAKE OF
SHEARING SHRTWV THRU WI.
TODAY...MODELS IN GOOD AGREEMENT SHOWING BAND OF HEAVIER RA
CONTINUING NE THRU THE CWA BUT TENDING TO DIMINISH AS THE FGEN
FORCING WEAKENS AS THIS BAND MOVES FARTHER N INTO LINGERING DRY AIR
MAINTAINED BY NW FLOW ALF OVER ONTARIO AND AWAY FM NEARLY STNRY FNT
LINGERING IN WI. THEN SOME DRY SLOTTING WILL IMPACT MAINLY THE
SCENTRAL BEFORE DPVA/LARGER SCALE QVECTOR CNVGC IN ADVANCE OF THE
APRCHG SHRTWV ARRIVE W-E AND CAUSE THE PCPN AREA TO EXPAND AGAIN/
INTENSIFY IN THE AFTN. WITH CLD COVER/RA...WL MAINTAIN PREVIOUS FCST
WELL BLO NORMAL MAX TEMPS NOT FAR FM 40.
TNGT...SHRTWV SLIDING ENEWD IS PROGGED TO SHEAR OUT AND MOVE MORE
QUICKLY TO THE E ACRS WI AS IT ENTERS THE UPR CONFLUENCE ZN BTWN THE
NRN AND SRN BRANCHES. WITH DIMINISHING DYNAMIC SUPPORT/MID LVL
DRYING ACCOMPANYING THE SHEARING SHRTWV...EXPECT PCPN COVERAGE/
INTENSITY TO GRDLY DIMINISH. WITH THE ARRIVAL OF COLDER AIR AS THE
LLVL FLOW BACKS MORE TO THE NE...GUIDANCE HINTS THE PCPN WL AT LEAST
MIX WITH SOME SN BEFORE ENDING ESPECIALLY OVER THE NRN TIER AS H85
TEMPS FALL AOB 0C. THE NAM INDICATES SEVERAL INCHES OF WET SN COULD
ACCUMULATE OVER THE HIER TERRAIN OF THE NCNTRL WITH LINGERING SLGTLY
CYC NE UPSLOPE FLOW AIDING COOLING/LIFT. THIS MODEL IS SLOWER THAN
MOST OF THE OTHER GUIDANCE IN SHEARING OUT THE SHRTWV/BRINGING IN
LARGER SCALE QVECTOR DVGC/HOLDING ON TO LLVL CYC FLOW. BUT SINCE
SOME OF THE OTHER HI RES MODELS INDICATE SOME PERSISTENT HIER QPF
OVER THE HIER TERRAIN OF THE NCENTRAL...WL MAINTAIN SOME HIER POPS
IN THIS AREA ALONG WITH A HIER QPF.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 349 AM EDT MON APR 25 2016
UPPER AIR PATTERN WILL FEATURE A COLD UPPER LEVEL TROUGH CENTERED
OVER QUEBEC MOST OF THIS WEEK WITH TROUGHING OVER WESTERN CONUS.
UPPER LAKES WILL RESIDE WITHIN CONFLUENT NW FLOW ALOFT ON EDGE OF
EASTERN CANADA TROUGH. RESULT IS HIGH PRESSURE EXPANDING OVER HUDSON
BAY EARLY THIS WEEK WILL PUSH A RIDGE OVER UPPER GREAT LAKES INTO
NEXT WEEKEND. PATTERN WILL LEAD TO DRY WEATHER WITH SEASONABLY COOL
TEMPERATURES. NO REAL SIGNIFICANT WARM UP IS IN SIGHT ATTM. IN FACT
IF ANYTHING THE 7-10 DAY PERIOD JUST BEYOND REACH OF THIS FORECAST
POINTS TO MORE COOLER AND UNSETTLED PATTERN AS TROUGHING OVER
WESTERN CONUS EVENTUALLY MAKES IT TO THE GREAT LAKES. EXTRAPOLATING
CPC DAY 8-14 OUTLOOK MADE ON APRIL 24TH SUGGESTS THAT WARMER AIR MAY
BEGIN TO MAKE ITS WAY OVER GREAT LAKES TOWARD MID MAY AND CPC 3-4
WEEK OUTLOOK GOOD THROUGH MID-LATE MAY SIGNALS A SWITCH TO ABOVE
NORMAL TEMPS. TIME WILL TELL IF THAT DOES INDEED OCCUR.
LINGERING EFFECTS FROM DEPARTING LOW PRESSURE SYSTEM ARE FEW BUT
COULD SHOW UP AS A FEW RAIN/SNOW SHOWERS EARLY ON TUESDAY...MAINLY
FOR UPSLOPE AREAS OF CNTRL CWA. AT THE LEAST...INCREASED SKY COVER
UNTIL LATE MORNING WHEN DRY AIR WITH THE HIGH BUILDING TO THE NORTH
SHOULD ERODE LOW CLOUDS STEADILY FROM NORTH TO SOUTH. SMATTERING OF
MID OR HIGH CLOUDS MAY TRY TO LINGER OVER SOUTHERN CWA...BUT OVERALL
SHOULD TURN INTO A MOSTLY SUNNY DAY FOR ALL CWA.
NO REAL SIGNIFICANT FORECAST ISSUES REST OF THIS WEEK AS THE HIGH
PRESSURE DOMINATES. SKIES SHOULD BE MOSTLY CLEAR AND WINDS NOT
PARTICULARLY STRONG/GUSTY. GRADIENT ONSHORE NORTHEAST WINDS OUT OF
THE HIGH WILL KEEP LAKE SUPERIOR SHORELINE COOLEST WITH DAYTIME
HIGHS MAINLY IN THE 40S. ELSEWHERE...TEMPS SHOULD GRADUALLY RISE
THROUGH THE 50S BY LATE WEEK. PERHAPS MAY SEE LOWER 60S WELL INLAND
FROM THE GREAT LAKES SHORES BY LATE THIS WEEK INTO NEXT WEEKEND...
BUT THAT WOULD ONLY COME FROM AIRMASS MODERATION AS THE OVERALL
TEMPS ALOFT WARM LITTLE. THE COOL AND DRY AIR MASS WITH THE HIGH
POINTS TO GOING ON LOWER END OF GUIDANCE FOR NIGHTTIME LOWS
ESPECIALLY INLAND.
CONSENSUS OF MODELS BRINGS SLIGHT CHANCES BACK OVER UPR MICHIGAN
NEXT SUNDAY. PREVIOUS ECMWF DROVE THOSE RELATIVELY HIGHER POPS...BUT
LATEST RUN HAS TRENDED FARTHER SOUTH WITH SFC-MID LEVEL LOW LIFTING
ACROSS MID MISSISSIPPI RIVER VALLEY. FARTHER SOUTH TREND WITH PRECIP
MAKES SENSE GIVEN THE STRONG/PERSISTENT/DRY HUDSON BAY HIGH THE
SYSTEM WILL BE RUNNING INTO.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 744 AM EDT MON APR 25 2016
WITH PERIODS OF RA AND A SHALLOW E FLOW OF CHILLY...MOIST AIR TO THE
N OF A STNRY FNT IN WI...EXPECT IFR/LIFR CONDITIONS TO DOMINATE THE
TAF SITES THIS FCST PERIOD. THE ARRIVAL OF DRIER AIR LATE TNGT AT
CMX WL BRING A RETURN OF COME CLRG AND VFR WX.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 AM EDT MON APR 25 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 INTO TONIGHT. OVER THE
WESTERN LAKE WHERE COASTAL CONVERGENCE/FUNNELING ENHANCE E TO NE
WINDS...GALE FORCE WINDS ARE EXPECTED THROUGH THIS EVENING. ACROSS
THE REST OF LAKE SUPERIOR...PLAN FOR WINDS OF 20-30KT. WINDS WILL
SLOWLY DIMINISH LATE TONIGHT/TUE MORNING...BUT MORE SO TUE NIGHT AS
THE NORTHERN ONTARIO HIGH PRES BUILDS INTO THE UPPER LAKES. E TO NE
WINDS GENERALLY UNDER 20KT WILL PREVAIL WED...THOUGH GUSTS TO 25 KTS
MAY OCCUR OVER WRN LAKE SUPERIOR. WINDS WILL DIMINISH TO LESS THAN
20KT THU/FRI ACROSS THE ENTIRE LAKE AS HIGH PRES SETTLES OVER THE
AREA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EDT /MIDNIGHT CDT/ TUESDAY FOR LSZ162-
263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...JLA
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
700 AM CDT MON APR 25 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 355 AM CDT Mon Apr 25 2016
Main focus today will be chances for thunderstorms.
Convection from early this morning continues to dissipate as the
upper level trof shears out and a loss of low level forcing. As the
trof lifts nwd, height rises build into the area, which shud
suppress convection thru at least the morning hours.
Mdls depict a outflow bndy or pre-frontal trof draped across the
nrn portions of the CWA later today. With the cdfnt remaining N of
the area, this bndy will be the focus for convection this afternoon.
Heating shud be sufficient to erode the cap in place, allowing
storms this afternoon. That said, there is some question on
placement of storms given the lingering convective debris. Still, it
appears there should be enuf MLCAPE, around 1000 J/kg according to
the more conservative GFS, as well as deep layer shear to support a
few potentially severe storms, lingering into the evening hours.
These values seem appropriate given the warm dewpoint bias in the
NAM.
As for temps, the sfc bndy and convective debris mentioned above
lead to uncertainty in the temps for today. Believe the cool spot in
the CWA will be mainly the nrn counties. Believe the warmer areas
will be generally from KJEF to KPPQ and areas to the SE with warmest
temps along a KVIH to KSTL line, just ahead of the surface bndy.
These temps are well depicted in the MOS and have trended at the
warmer MOS for the area. The RAP and local 4km WRF suggest even
warmer temps, but too many questions in cloud cover today to go that
warm attm.
Tilly
.LONG TERM... (Tonight through Sunday)
Issued at 355 AM CDT Mon Apr 25 2016
The weather is about to get a lot more active for this week, with a
sustained period for the threat of severe storms.
An upper level Rex Block covering much of North America will
continue to prevail thru much of this week, with a RIDGE over the
Canadian Prairie and TROFs flanking it on the coasts. Complimenting
this will be a series of strong Pacific storm systems that will run
just south thru the CONUS, 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 be well on its way to becoming absorbed
into the main flow by this evening, but the main focus at this point
will be where an old convective surface boundary will be. Several
models are in good agreement on firing this up either just before
00z/Tue or right at, when the CINH aloft can weaken just enough, and
once it gets going, should be able to sustain development for a good
portion of the evening, if not into the late night. Enough
instability may be able to be tapped during a small window of time
early this evening for isolated severe storms possible.
A cold front will drop down very late tonight into Tuesday and then
stall at some point over our forecast area, probably just north of I-
70, and will maintain a chance for storms. Should be decent
moisture pooling near the front by Tuesday afternoon, and while
shear is sub-par, MLCAPE near the stalled frontal boundary will be
around 3000 J/kg and would support some severe storms thru magnitude
of instability alone.
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 Tuesday night into Wednesday morning.
Along with an increase of broadscale lift, this should result in
elevated storms, with hail as their primary severe threat during
that time.
Heading into Wednesday afternoon and evening, things look much more
muddled than they did 24-48hrs ago, with the severe threat and mode
still heavily dependent on how far north the warm front gets by this
time. Models continue to show enough variation with frontal
position for low-medium confidence, which for forecast purposes for
now will be near or just north of the I-70 corridor. If the rain
coverage is as high as what several model solutions are suggesting,
this may also work to lower the severe potential on this day,
limiting instability more than previously thought. Either way,
shear will increase substantially as the storm system approaches and
instability may not need to be as high as what it was Tuesday anyway
to justify a continuation of a severe risk.
Things dry out briefly from late Thursday thru early Friday 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 to the south.
Otherwise, daytime max temps will begin much above average this
week, but then slide back towards average for late week and the
upcoming weekend. If the models showing the loss of the western
TROF is accurate for late week, this should result in a slide
towards more of a NW flow aloft pattern for the following week, and
could yield a period of more tranquil wx.
TES
&&
.AVIATION... (For the 12z TAFs through 12z Tuesday Morning)
Issued at 637 AM CDT Mon Apr 25 2016
TSRA are expected to develop this afternoon possibly impacting
COU/UIN into the early evening hours. This threat will drift swd
reaching SUS/CPS late tonight. These TSRA will also coincide with
MVFR cigs. Otherwise, winds will pick up with gusts to around 20
kts today, before diminishing tonight. Winds will veer to become
swly this afternoon and remain tonight.
Specifics for KSTL: Strong sly winds today with gusts to around 20
kts. TSRA possible late tonight with MVFR cigs. These cigs shud
lift Tues morning, tho current timing is uncertain and going TAF
may be too early.
Tilly
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
631 AM CDT MON APR 25 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CDT MON APR 25 2016
TODAY AND TONIGHT...LOW PRESSURE TRACKS INTO THE UPPER MIDWEST
SENDING A COLD FRONT THROUGH THE FCST AREA THIS MORNING. A STRONG
MODEL CONSENSUS SHOWS LIGHT AND VARIABLE WINDS AROUND 21Z FROM KAIA-
KLBF WITH SOUTHEAST RETURN FLOW UNDERWAY ACROSS SWRN NEB.
THERE IS A MODEST OPPORTUNITY FOR DESTABLIZATION ON THE NRN COLO
FRONT RANGE AND LARAMIE RANGE DEVELOPS AROUND 21Z WHICH COULD MOVE
INTO THE SRN/CNTL PANHANDLE THIS EVENING. SPC SUGGESTED A MARGINAL
HAIL AND WIND THREAT EARLY THIS EVENING ACROSS THE PANHANDLE.
PRESUMABLY THE ATM REMAINS CAPPED ELSEWHERE UNTIL LATE TONIGHT. THE
NAM AND GFS SUGGESTED ELEVATED INSTABILITY BUT A STRONG CAP WHICH
WEAKENS AFTER 09Z.
HIGHS TODAY RISE INTO THE 60S...NEAR 70 FAR SOUTH. SKIES SHOULD BE
MOSTLY CLEAR BY LATE MORNING ACROSS NRN NEB. RETURN MOISTURE FROM
THE SOUTH AND HIGH CLOUDS TONIGHT HOLD UP LOWS IN THE UPPER 30S
NORTH TO MID 40S SOUTH WHERE THE NAM AND ECM SHOW STRATUS
DEVELOPING. THE DEEPER EASTERLY MOISTURE ADVECTION ACROSS SRN NEB
MAY FAVOR DRIZZLE OR LIGHT RAIN VS THUNDERSTORM DEVELOPMENT. GIVEN
THE STRENGTH OF THE MOISTURE ADVECTION...THUNDERSTORMS ARE IN PLACE
TONIGHT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 343 AM CDT MON APR 25 2016
BEGINNING 12Z TUESDAY. THE PROBABILITY OF CONVECTIVE STORMS
REACHING SEVERE LIMITS IS INCREASING FOR TUESDAY. THIS THREAT IS
THE PRIMARY FORECAST CONCERN GOING IN THE EXTENDED PERIODS. IN
ADDITION TO THE CONVECTIVE THREAT...MEASURABLE RAINFALL...SOME OF
WHICH MAY BE MODERATE OR HEAVY IS FORECAST.
THE LONG RANGE MODELS AND ENSEMBLES CONTINUE TO ADVERTISE A SOLUTION
WHERE UNSETTLED AND COOL CONDITIONS PREVAIL THROUGH THE EXTENDED.
THE UNSETTLED WEATHER IS THE RESULT OF A PERSISTENT LONGWAVE TROUGH
OVER THE WESTERN CONUS WHICH WILL EJECT A SERIES OF WAVES/UPPER
LEVEL ENERGY ACROSS THE ROCKIES OUT ONTO THE PLAINS. SEVERAL OF THE
WAVES ACTUALLY TAKE ON A NEGATIVE TILT EAST OF THE ROCKIES AND CLOSE
OFF A LOW WHICH THEN SLOWLY MEANDER THROUGH THE REGION. THE FIRST
SIGNIFICANT CLOSED LOW ARRIVES OVER THE CENTRAL ROCKIES EARLY ON
TUESDAY. IN RESPONSE A SURFACE LOW IS SHOWN TO DEEPEN OVER
NORTHEASTERN COLORADO...WITH A WARM FRONT ARCING TO THE EAST ACROSS
FAR SOUTHERN NEBRASKA. DPVA...WAA...INITIAL HIGH PLAINS SPEED MAX
AND GULF MOISTURE STREAMING NORTH IN ADVANCE OF THE MID LEVEL CLOSED
LOW WILL PROMOTE THE DEVELOPMENT OF STRATUS AND POSSIBLY
SHOWERS/THUNDER EARLY ON THE DAY ON TUESDAY ACROSS THE SANDHILLS
REGION. THE INITIAL CONVECTIVE DEVELOPMENT IS UNCERTAIN DUE TO
MINIMAL INSTABILITY...BUT AS THE AFTERNOON PROGRESSES THE MODELS
DEPICT INCREASING CAPE AS THE LOW LIFTS THE FRONT NORTH INTO
SOUTHERN NEBRASKA. SEVERE STORMS ARE POSSIBLE WITH THE TRIAD OF
TYPICAL THREATS. LARGE HAIL AND WIND ARE MOST LIKELY GENERALLY
ALONG AND SOUTH OF I80...AND EAST THROUGH CUSTER COUNTY INTO WHEELER
COUNTY...WITH A TORNADO THREAT NEAR THE TRIPLE POINT AND EAST /SW
NEB/ AND EAST ALONG THE WARM FRONT. NAM BUFR SOUNDINGS THOUGH SHOW
FAVORABLE 0-1KM SHEAR AND HELICITY VALUES FOR TORNADIC DEVELOPMENT
DURING THE EVENING HOURS FROM SOUTHWEST LINCOLN COUNTY NORTHEAST
INTO SOUTHEASTERN WHEELER. THE CURRENT DAY TWO SPC CONVECTIVE
OUTLOOK NOW HAS FAR SOUTHEASTERN PORTIONS OF THE CWA IN THE ENHANCED
RISK WITH A MODERATE RISK JUST AT OUR SOUTHEASTER DOORSTEP. WILL
NEED TO CONTINUE TO MONITOR THE SITUATION...ESPECIALLY IF DEEPER
MOISTURE IS DRAWN BACK FURTHER WEST INTO THE LOW...OR IF THE MODELS
CONTINUE TO TREND NORTH WITH THE WARM FRONT.
THE MODELS ARE SHOWING AN UPTICK IN CONVECTIVE POTENTIAL LASTING
THROUGH THE OVERNIGHT TUESDAY AND AGAIN WEDNESDAY FOR GENERALLY THE
EASTERN THIRD OF THE CWA...AND MOST OF THE SOUTH...HOWEVER
CONVECTIVE INDICES ARE SUGGESTING A FAR LESSER CHANCE OF STRONG OR
SEVERE STORMS ON WEDNESDAY. THE UPPER LOW WILL HAVE MADE LITTLE
EASTWARD PROGRESS...PRECIPITATION CHANCES REMAIN THROUGH THE DAY ON
WEDNESDAY AND INTO THURSDAY. THE MODELS PROJECT SOME DRYING FROM
THE SOUTHWEST WEDNESDAY...SO THE GREATEST POPS REMAIN ACROSS THE
NORTH AND EAST WITH JUST SLIGHT CHANCES ACROSS OUR SOUTHWEST. A
COOLER AIRMASS IS SEEN WITH THIS LOW...AND IT/S NOT OUT OF THE
QUESTION TO SEE TEMPERATURES FALL ENOUGH ACROSS NW NEB FOR A MIX OF
RAIN AND SNOW WEDNESDAY AND THURSDAY MORNING. NO ACCUMULATIONS ARE
FORECAST THOUGH.
THE LOW IS DRAWN EAST ON THURSDAY LEAVING ONLY A SLIGHT CHANCE FOR
POPS...HOWEVER THE REPRIEVE WILL BE BRIEF AS THE NEXT SW ORGANIZES
OVER THE DESERT SOUTHWEST AND EJECTS NORTHEAST ACROSS THE SOUTHERN
ROCKIES. THE MODELS HAVE THE LOW A BIT FURTHER SOUTH WITH TONIGHT/S
RUN THAN COMPARED 24 HOURS AGO...BUT THE RESULT IS THE SAME.
INCREASING POPS ARE FORECAST BEGINNING FRIDAY...WITH SOLID RAIN
CHANCES REMAINING THROUGH THE ENTIRE WEEKEND AS THE LOW SLOWS AND
TAKES ON A NEGATIVE TILT OVER THE CENTRAL HIGH PLAINS. SEVERE
WEATHER IS NOT ANTICIPATED AS TEMPERATURES WILL STILL BE INFLUENCED
BY THE PREVIOUS COOL AIRMASS...BUT WEAK INSTABILITY IS SHOWN TO
REDEVELOP...SO WILL GO WITH AN ISO MENTION
THROUGH THE EXTENDED FORECAST...PERIODS OF RAINFALL WILL ADD
UP...ESPECIALLY IF AN AREA IS IMPACTED BY SEVERAL ROUNDS OF
CONVECTION. RAINFALL THROUGH NEXT WEEKEND COULD APPROACH A COUPLE
INCHES IN LOCATIONS. AT THIS POINT THE CENTRAL SANDHILLS NORTH HAVE
THE GREATEST CHANCES OF SEEING 1-2 INCHES OF TOTAL QPF. OTHERWISE
TEMPERATURES UNDER THE UNSETTLED AIRMASS WILL REMAIN COOL...WITH
HIGHS AND LOWS NEAR OR BELOW AVERAGE THROUGH THE EXTENDED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 631 AM CDT MON APR 25 2016
VFR IS GENERALLY EXPECTED TODAY AND THIS EVENING.
THEREAFTER...IFR/MVFR CIGS ARE EXPECTED AS UPSLOPE FLOW INCREASES.
TSTMS ARE EXPECTED TO FORM ON THE NRN COLO FRONT RANGE AND
LARAMIE RANGE AROUND 21Z THIS AFTERNOON WHICH COULD MOVE INTO THE
SRN/CNTL PANHANDLE THIS EVENING. THEN SHOWERS AND THUNDERSTORMS
MAY DEVELOP FROM 06Z ONWARD TONIGHT. THE SLOWER GFS GENERATES NO
RAIN WHILE THE FASTER ECM AND NAM DO. THE RAP IS HINTING AT THE
SLOWER GFS SOLN.
THE INCREASE IN MOISTURE TONIGHT FED BY LOW LEVEL EASTERLIES WILL
AT SOME POINT PRODUCE IFR/MVFR CIGS WITH LOWER CIGS WEST ACROSS
THE PANHANDLE. THIS FEATURE COULD DEVELOP 06Z-09Z IN THE NAM/ECM
OR AS LATE AS 12Z-15Z IN THE SLOWER GFS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS MEDFORD OR
452 AM PDT MON APR 25 2016
.UPDATED AVIATION DISCUSSION.
.DISCUSSION...THE CLOSED LOW PRESSURE HAS MOVED INTO NORTHERN
CALIFORNIA THIS MORNING. THE LOW IS EXPECTED TO CONTINUE TO MOVE
SOUTHEAST INTO NEVADA. ISOLATED SHOWERS CONTINUE FROM THE CASCADES
WEST. SNOW SHOWERS WILL CONTINUE OVER THE WARNERS THIS MORNING
FROM MOISTURE WRAPPED AROUND THE LOW BUT BY THIS AFTERNOON THE
ATMOSPHERE IS EXPECTED TO STABILIZE UNDER NW FLOW ALOFT.
WE ARE EXPECTING LESS CLOUD COVER TONIGHT THAN PREVIOUSLY THOUGHT
AND THE RADIATIONAL COOLING COULD BRING OVERNIGHT LOWS FOR SW
OREGON AND NORTHERN CALIFORNIA VALLEYS INTO THE LOWER TO MID 30S
AND FROST IS POSSIBLE OVERNIGHT. PLEASE TAKE NEEDED PRECAUTIONS TO
AVOID FROST DAMAGE.
NO PRECIPITATION IS IN THE FORECAST FOR INLAND AREAS TUESDAY AS A
RIDGE BUILDS INTO THE AREA.THE ONLY EXCEPTION IS IN OUR MARINE
ZONES WHERE THE NEXT FRONT COULD SPREAD LIGHT RAIN LATE IN THE
DAY. THE WARM FRONT IS EXPECTED TO SPREAD LIGHT RAIN INLAND
TUESDAY NIGHT. THE UPPER LEVEL SUPPORT FOR THIS NEXT SYSTEM DIVES
INTO NORTHERN CALIFORNIA AGAIN ON WEDNESDAY BUT THERE WILL STILL
BE ENOUGH MOISTURE AND INSTABILITY TO PRODUCE SHOWERS IN SOUTHERN
OREGON.
SHOWERS WILL LINGER ACROSS THE WARNER MOUNTAINS ON THURSDAY BUT
THE REST OF OUR FORECAST AREA IS EXPECTED TO BE DRY. /FB
&&
.AVIATION...FOR THE 25/12Z TAF CYCLE...PLENTY OF LOW LEVEL MOISTURE
REMAINS THIS MORNING AND THIS HAS RESULTED IN IFR CIGS/VIS THAT
DEVELOPED WITHIN THE LAST COUPLE OF HOURS AT ROSEBURG. EXPECT THESE
CONDITIONS TO LAST FOR MOST OF THE MORNING, ALTHOUGH THERE IS A
CHANCE CIGS COULD IMPROVE TO MVFR AROUND 18Z. ELSEWHERE EXPECT VFR
CIGS TO BE THE PREDOMINATE CONDITION, BUT MOUNTAINS ARE EXPECTED TO
BE AT LEAST PARTLY OBSCURED THIS MORNING. ALSO CIGS COULD SEE SAW
BRIEFLY FROM VFR TO MVFR AT KLAMATH FALLS THIS MORNING, BUT
CONFIDENCE IS LOW, SO KEPT IT OUT OF THE TAF. STABLE CONDITIONS WILL
CONTINUE TONIGHT WITH A CHANCE FOR IFR CIGS TO RETURN AT ROSEBURG.
-PETRUCELLI
&&
.MARINE...UPDATED 300 AM PDT MON 25 APR 2016...MODELS CONTINUE TO
SHOW LOW END SMALL CRAFT FOR SEAS WITH A WEST DOMINATED SWELL
AFFECTING ALL THE THE MARINE WATERS THROUGH THIS EVENING. HIGH
PRESSURE WILL BUILD OFFSHORE TODAY AND NORTH WINDS ARE EXPECTED TO
INCREASE. THE RAP SHOWS SMALL CRAFT FOR WINDS EDGING CLOSER TOWARDS
THE COAST, SO HAVE ADJUSTED THE SMALL CRAFT FOR WINDS TO REFLECT
THIS THIS THINKING. HIGH PRESSURE WILL WEAKEN AND MOVE OVER THE
WATERS TONIGHT THROUGH TUESDAY. A WEAK FRONT WILL MOVE THROUGH THE
WATERS TUESDAY NIGHT...THEN OFFSHORE HIGH PRESSURE REBUILDS AGAIN
WEDNESDAY AFTERNOON. THE MODELS REMAIN IN FAIRLY GOOD AGREEMENT
SHOWING A THERMAL TROUGH DEVELOPING AND STRENGTHENING BY THE LATTER
PART OF THE WEEK. WINDS IN THE SOUTHERN WATERS COULD REACH HIGH END
SMALL CRAFT BY THURSDAY WITH GALES POSSIBLE OVER THE SOUTHERN
PORTIONS OF MARINE ZONES 356 AND 376. NOTE THAT DETAILS ON THIS
COULD CHANCE, SO WATCH FOR UPDATES ON THIS. -PETRUCELLI
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 11 PM PDT THIS
EVENING FOR PZZ356-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
EVENING FOR PZZ350-356-370-376.
$$
AREA FORECAST DISCUSSION
NWS MEDFORD OR
315 AM PDT MON APR 25 2016
.DISCUSSION...THE CLOSED LOW PRESSURE HAS MOVED INTO NORTHERN
CALIFORNIA THIS MORNING. THE LOW IS EXPECTED TO CONTINUE TO MOVE
SOUTHEAST INTO NEVADA. ISOLATED SHOWERS CONTINUE FROM THE CASCADES
WEST. SNOW SHOWERS WILL CONTINUE OVER THE WARNERS THIS MORNING
FROM MOISTURE WRAPPED AROUND THE LOW BUT BY THIS AFTERNOON THE
ATMOSPHERE IS EXPECTED TO STABILIZE UNDER NW FLOW ALOFT.
WE ARE EXPECTING LESS CLOUD COVER TONIGHT THAN PREVIOUSLY THOUGHT
AND THE RADIATIONAL COOLING COULD BRING OVERNIGHT LOWS FOR SW
OREGON AND NORTHERN CALIFORNIA VALLEYS INTO THE LOWER TO MID 30S
AND FROST IS POSSIBLE OVERNIGHT. PLEASE TAKE NEEDED PRECAUTIONS TO
AVOID FROST DAMAGE.
NO PRECIPITATION IS IN THE FORECAST FOR INLAND AREAS TUESDAY AS A
RIDGE BUILDS INTO THE AREA.THE ONLY EXCEPTION IS IN OUR MARINE
ZONES WHERE THE NEXT FRONT COULD SPREAD LIGHT RAIN LATE IN THE
DAY. THE WARM FRONT IS EXPECTED TO SPREAD LIGHT RAIN INLAND
TUESDAY NIGHT. THE UPPER LEVEL SUPPORT FOR THIS NEXT SYSTEM DIVES
INTO NORTHERN CALIFORNIA AGAIN ON WEDNESDAY BUT THERE WILL STILL
BE ENOUGH MOISTURE AND INSTABILITY TO PRODUCE SHOWERS IN SOUTHERN
OREGON.
SHOWERS WILL LINGER ACROSS THE WARNER MOUNTAINS ON THURSDAY BUT
THE REST OF OUR FORECAST AREA IS EXPECTED TO BE DRY. /FB
&&
.AVIATION...FOR THE 25/06Z TAF CYCLE...SHOWERS CONTINUE TO DIMINISH
RAPIDLY AS AN UPPER LOW MOVES OFF TO THE EAST, AND THEY HAVE BEEN
REMOVED FROM ALL TAFS. THERE IS PLENTY OF LOW LEVEL MOISTURE LEFT SO
WE WILL SEE A MIX OF MVFR AND VFR CIGS TONIGHT THROUGH MONDAY
MORNING WITH VFR THEREAFTER. IF WE GET ENOUGH CLEARING WE COULD SEE
PATCHY VALLEY FOG AROUND SUNRISE, BUT CONFIDENCE IS NOT HIGH ENOUGH
TO INCLUDE IN THE TAFS. -WRIGHT
&&
.MARINE...UPDATED 300 AM PDT MON 25 APR 2016...MODELS CONTINUE TO
SHOW LOW END SMALL CRAFT FOR SEAS WITH A WEST DOMINATED SWELL
AFFECTING ALL THE THE MARINE WATERS THROUGH THIS EVENING. HIGH
PRESSURE WILL BUILD OFFSHORE TODAY AND NORTH WINDS ARE EXPECTED TO
INCREASE. THE RAP SHOWS SMALL CRAFT FOR WINDS EDGING CLOSER TOWARDS
THE COAST, SO HAVE ADJUSTED THE SMALL CRAFT FOR WINDS TO REFLECT
THIS THIS THINKING. HIGH PRESSURE WILL WEAKEN AND MOVE OVER THE
WATERS TONIGHT THROUGH TUESDAY. A WEAK FRONT WILL MOVE THROUGH THE
WATERS TUESDAY NIGHT...THEN OFFSHORE HIGH PRESSURE REBUILDS AGAIN
WEDNESDAY AFTERNOON. THE MODELS REMAIN IN FAIRLY GOOD AGREEMENT
SHOWING A THERMAL TROUGH DEVELOPING AND STRENGTHENING BY THE LATTER
PART OF THE WEEK. WINDS IN THE SOUTHERN WATERS COULD REACH HIGH END
SMALL CRAFT BY THURSDAY WITH GALES POSSIBLE OVER THE SOUTHERN
PORTIONS OF MARINE ZONES 356 AND 376. NOTE THAT DETAILS ON THIS
COULD CHANCE, SO WATCH FOR UPDATES ON THIS. -PETRUCELLI
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 11 PM PDT THIS
EVENING FOR PZZ356-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
EVENING FOR PZZ350-356-370-376.
$$
FJB/FJB/TRW
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
655 AM CDT MON APR 25 2016
.AVIATION...
/12Z TAFS/
MVFR/IFR CIGS ARE EXPECTED ACROSS THE AREA TERMINALS THROUGH
15Z/16Z TIME FRAME. LOW LEVEL CLOUDS ARE EXPECTED TO ERODE AND
LIFT FOR VFR CONDITIONS THIS AFTERNOON AND EVENING. ISOLATED
SHOWERS/THUNDERSTORMS ARE POSSIBLE LATE THIS AFTERNOON AND EARLY
EVENING ACROSS THE NORTHERN PART OF THE HILL COUNTRY INCLUDING
KAUS. HOWEVER...PROBABILITY IS LESS THAN 20 PERCENT. MVFR/IFR CIGS
ARE EXPECTED ALONG THE I-35 SITES LATE THIS EVENING INTO TUESDAY
MORNING AS MOISTURE RETURNS. A POWERFUL WEATHER SYSTEM IS FORECAST
TO PUSH ACROSS THE SOUTHERN PLAINS TUESDAY. STRONG TO SEVERE
STORMS ARE EXPECTED LATE TUESDAY AFTERNOON AND EVENING ACROSS THE
HILL COUNTRY AND BOTH AUSTIN AND SAN ANTONIO METRO AREAS.
LARGE HAIL AND THUNDERSTORM WIND GUSTS OF 45 TO 55 KNOTS MAY BE
POSSIBLE.
&&
.PREV DISCUSSION... /ISSUED 406 AM CDT MON APR 25 2016/
SHORT TERM (TODAY THROUGH TUESDAY)...
THE POSSIBILITY OF STRONG TO SEVERE THUNDERSTORMS WILL BE THE
MAIN HIGHLIGHT OF THIS FORECAST PERIOD LATE AFTERNOON TUESDAY
INTO EARLY WEDNESDAY MORNING. LARGE HAIL AND DAMAGING WINDS APPEAR
TO THE PRIMARY THREATS AT THIS TIME. PLEASE STAY TUNED FOR FURTHER
UPDATES AS TIMING AND EVOLUTION BECOME MORE CLEAR.
LOW-LVL MOISTURE IS STREAMING IN ON SOUTHEAST WINDS THIS MORNING
AND CREATING WIDESPREAD OVERCAST SKY CONDITIONS. CLOUDS WILL
SLOWLY DISSIPATE THROUGH THE LATE MORNING WITH MORE SUN EXPECTED
THIS AFTERNOON. WITH SOUTH TO SOUTHWEST 925-700MB WINDS,
TEMPERATURES WILL CLIMB ABOVE NORMAL INTO THE UPPER 80S TO LOW 90S
WITH SOME MID 90S POSSIBLE ACROSS THE RIO GRANDE. AS FURTHER
HEATING OCCURS THIS AFTERNOON, DEWPOINTS WILL MIX OUT INTO THE LOW
TO MID 60S WITH PWATS NEAR 1.4". LACK OF DEEPER MOISTURE AND A
MID TO UPPER LEVEL TRIGGER MAY NOT ALLOW FOR SHOWER OR STORM
GENERATION THIS AFTERNOON DESPITE THE NEAR 3000 J/KG SBCAPE. A
CAPPING INVERSION IN PLACE MAY JUST BE SLIGHTLY TOO STRONG FOR
THUNDERSTORM INITIATION ON PARCEL BUOYANCY ALONE. THE NEW SPC SSEO
DOES SUGGEST SOME ACTIVITY COULD BE POSSIBLE IN THE 7-10PM RANGE
WHILE HRRR AND TEXAS TECH WRF DO NOT AGREE. GLOBAL MODELS SHOW
HINTS OF VERY ISOLATED ACTIVITY. IF A STORM WAS ABLE TO BREAK
THROUGH THE CAP...IT COULD BECOME STRONG GIVEN THE STEEP LAPSE
RATES IN PLACE. WILL HAVE MENTION SUPER LOW END CHANCES WITH
SLIGHT CHANCE THUNDER WORDING FOR WEAKER CAPPING AREAS THIS
AFTERNOON. A QUIET OVERNIGHT INTO TUESDAY MORNING IS EXPECTED WITH
LOW CLOUDS BUILDING BACK INTO THE REGION.
H5 HEIGHT FALLS WILL BEGIN EARLY TUESDAY MORNING ACROSS THE BIG
BEND OF TEXAS THAT MAY HELP SPARK OFF A FEW SHOWERS OVER THE
EDWARDS PLATEAU. MOST OF THIS ACTIVITY SHOULD STAY NORTH OF THE
REGION THROUGH THE EARLY AFTERNOON. A POWERFUL WEATHER SYSTEM
WILL PIVOT ACROSS THE SOUTHERN PLAINS DURING THE AFTERNOON. THE
STRONGEST FORCING WILL REMAIN NORTH WHERE THE BULK OF SEVERE
STORMS ARE EXPECTED. FARTHER SOUTH - CAPPING WILL INITIALLY KEEP
SHOWER AND STORM COVERAGE AT BAY UNTIL THE LATE AFTERNOON HOURS.
BUFR SOUNDINGS INDICATE THE INVERSION WEAKENING BY 4-6PM AND
INCREASED COVERAGE COULD OCCUR DURING THIS TIME OVER THE HILL
COUNTRY TO POSSIBLY THE I35 CORRIDOR. CONTINUED STEEP LAPSE RATES
NEAR 8 C/KM AND 30-40 KT DEEP LAYER SHEAR SHOULD SUPPORT STRONG TO
SEVERE STORMS. THE SPC HAS EXPANDED THE SLIGHT RISK OF SEVERE
STORMS FARTHER SOUTH AND WEST TUESDAY AFTERNOON AND INTO THE
OVERNIGHT. LARGE HAIL AND STRAIGHT-LINE DAMAGING WINDS WILL BE
THE MOST LIKELY HAZARDS BUT A TORNADO CAN NOT BE RULED OUT. LOW-
LVL SHEAR DOES NOT LOOK TO BE OVERLY IMPRESSIVE BUT 0-3KM SHEAR
VECTOR ORIENTATION SHOULD SUPPORT SEMI-DISCRETE STORMS THAT COULD
ACT TO SUPPORT THE LOW-END TORNADO RISK. ADDITIONAL HEIGHT FALLS
THROUGH MIDNIGHT FROM A SECONDARY IMPULSE COULD HELP ORGANIZE THE
STORMS INTO A LINE AND SHIFT IT SOUTHEAST THROUGH WEDNESDAY
MORNING. OVERALL STRENGTH OF THE LINE SHOULD DECREASE BUT SOME
CONTINUED STRONG STORMS COULD BE POSSIBLE. POCKETS OF HEAVY RAIN
WILL ALSO BE POSSIBLE BUT OVERALL COVERAGE SHOULD BE LOW ENOUGH TO
PRECLUDE A FLASH FLOOD WATCH. THIS ACTIVITY A SHOULD HELP FORCE
THE DRYLINE BOUNDARY THROUGH MOST OF THE REGION WEDNESDAY WITH
DRYING AND CLEARING THROUGH THE DAY.
LONG TERM (WEDNESDAY THROUGH SUNDAY)...
A CONTINUED ACTIVE PATTERN WILL PERSIST LATE WEEK AND EARLY
WEEKEND WITH SOME POTENTIAL IMPACTS FROM HEAVY RAINFALL AND
ANOTHER POSSIBILITY OF STRONG TO SEVERE STORMS.
THE DRYLINE/BOUNDARY SHOULD BE ALONG TO JUST INLAND FROM THE COAST
ON WEDNESDAY WITH DRIER AIR IN PLACE OVER MUCH OF SOUTH-CENTRAL
TEXAS. HOWEVER, BY THURSDAY, THE BOUNDARY WILL SHIFT BACK WEST TO
THE RIO GRANDE AS A SURFACE LOW DEVELOPS NEAR THE BIG BEND WITH
ANOTHER NEGATIVE TILTED TROUGH SWINGING ACROSS THE SW CONUS. AN
IMPLIED IMPULSE AHEAD OF THE PARENT LOW IS DEPICTED IN THE GFS/GEM
AND THIS COULD HELP GENERATE SCATTERED SHOWERS AND THUNDERSTORMS
THURSDAY AFTERNOON. WILL NEED TO MONITOR IF THESE CAN BECOME
STRONG TO SEVERE.
FRIDAY INTO SATURDAY WILL FEATURE THE PARENT CUT-OFF LOW MOVING
OVER NORTH TEXAS INTO THE GREAT PLAINS WITH A STRONG DIFFLUENT
UPPER JET STRUCTURE OVER SOUTH TEXAS. PWATS IN THE 1.6-1.9" ARE
PROGGED TO BE IN PLACE AS DECENTLY AGREED UPON MODEL GUIDANCE
SUGGESTS STRONG SYNOPTIC VERTICAL MOTION IN PLACE. THIS SET-UP
COULD LEAD TO PERIODS OF HEAVY RAIN FRIDAY AFTERNOON INTO SATURDAY
ALONG WITH STRONG TO SEVERE HAZARDS. THIS TIMEFRAME WILL NEED TO
WATCHED CLOSELY THROUGH THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 88 71 86 66 87 / 10 10 30 60 10
AUSTIN BERGSTROM INTL AIRPORT 87 70 86 66 86 / 10 10 30 60 10
NEW BRAUNFELS MUNI AIRPORT 88 70 87 66 87 / 10 10 30 50 10
BURNET MUNI AIRPORT 86 68 85 61 85 / 10 10 30 70 10
DEL RIO INTL AIRPORT 92 70 93 62 90 / - - 10 20 -
GEORGETOWN MUNI AIRPORT 85 70 85 64 86 / 10 10 30 70 10
HONDO MUNI AIRPORT 92 70 88 64 89 / 10 10 20 40 10
SAN MARCOS MUNI AIRPORT 87 70 86 66 86 / 10 10 30 50 10
LA GRANGE - FAYETTE REGIONAL 85 71 86 69 86 / 10 10 20 50 20
SAN ANTONIO INTL AIRPORT 89 71 86 67 87 / 10 10 30 50 10
STINSON MUNI AIRPORT 90 71 89 68 88 / 10 10 20 40 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...17
SYNOPTIC/GRIDS...ALLEN
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
128 PM PDT MON APR 25 2016
.SYNOPSIS...
PARTLY TO MOSTLY CLOUDY AND COOL TODAY WITH STRONG AND GUSTY WEST
WINDS...AND ISOLATED LIGHT SHOWERS OVER AND WEST OF THE MOUNTAINS.
WINDS IN THE DESERTS MAY BE STRONG ENOUGH TO PRODUCE DAMAGE AND
LOW VISIBILITY IN BLOWING DUST AND SAND. DRY AND A LITTLE WARMER
FOR TUESDAY AND MOST OF WEDNESDAY UNDER WEAK HIGH PRESSURE ALOFT.
SIGNIFICANT COOLING AGAIN FOR LATE WEDNESDAY AND THURSDAY WITH
SHOWERS AND MOUNTAIN SNOW...ALONG WITH GUSTY WEST WINDS IN THE
MOUNTAINS AND DESERTS. THE SHOWERS TAPER OFF ON FRIDAY...BUT
CONDITIONS REMAIN COOL BEFORE WARMING DURING THE WEEKEND AS HIGHER
PRESSURE ALOFT STARTS TO NUDGE INTO THE WEST.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
WATER VAPOR SATELLITE SHOWS A LOW PRESSURE SYSTEM ROTATING OVER
NEVADA...AND A VORT MAX IS NOTED OVER CENTRAL CALIFORNIA. THE 12Z
MIRAMAR SOUNDING SHOWED 850 MB WESTERLY WINDS OF 35 KT...WHICH IS
A LITTLE STRONGER THAN MODELS INDICATED PREVIOUSLY. ONSHORE
PRESSURE GRADIENTS ARE ALSO STRONGER THAN THE MODELS SHOWED...AS
THEY ARE CURRENTLY 14.4 MB FROM SAN DIEGO TO LAS VEGAS...AND 8.2 MB
FROM SAN DIEGO TO THERMAL. CURRENTLY...WINDS AT MOUNTAIN
RIDGES...DESERT SLOPES AND ADJACENT DESERTS ARE INCREASING...WITH
GUSTS REACHING 40-50 MPH. THE AFOREMENTIONED VORT MAX WILL ROTATE
AROUND THE LOW AND INTO SOUTHERN CALIFORNIA LATER TODAY AND THIS
EVENING...CREATING STRONGER WINDS IN ALL AREAS...PARTICULARLY
ALONG THE DESERT SLOPES AND INTO THE DESERTS WHERE 35-45 KT
SUSTAINED WINDS ALOFT COULD SURFACE. IF THESE STRONG WINDS
SURFACE IN THE DESERTS...IMPACTS SUCH AS POSSIBLE STRUCTURAL
DAMAGE AND NEAR ZERO VISIBILITY DUE TO BLOWING SAND/DUST WOULD BE
POSSIBLE. A HIGH WIND WARNING CONTINUES FOR THE DESERTS WHILE WIND
ADVISORIES REMAIN IN EFFECT FOR ALL OTHER AREAS. WINDS WILL
DIMINISH LATE TONIGHT INTO TUESDAY MORNING AS THE WAVE MOVES TO
THE EAST.
MEANWHILE...THERE WERE ISOLATED SHOWERS PRODUCING LIGHT
PRECIPITATION AMOUNTS IN THE MOUNTAINS...WITH THE SAN BERNARDINO
COUNTY MOUNTAINS...AND THE SAN GORGONIO WILDERNESS IN
PARTICULAR...GETTING THE MAJORITY OF THE SHOWER ACTIVITY...WHERE
A PERSISTENT LINE OF SHOWERS PRODUCING NEAR A HALF INCH AND UP TO
1.1 INCHES. THERE WERE ALSO SOME REPORTS OF A DUSTING OF SNOW UP
IN THE BIG BEAR AREA. CURRENTLY...RADAR SHOWS THAT SHOWER ACTIVITY
HAS DISSIPATED FOR THE MOST PART. HOWEVER...THE HRRR SHOWS
SHOWERS RE-DEVELOPING OVER THE SAN BERNARDINO COUNTY
MOUNTAINS...INLAND EMPIRE AND INTO THE RIVERSIDE COUNTY
MOUNTAINS/DESERTS LATE THIS AFTERNOON INTO THE EVENING AS THE
UPPER LEVEL WAVE MOVES THROUGH. ADDITIONAL PRECIPITATION AMOUNTS
OF 0.05-0.25 INCHES COULD OCCUR IN THE MOUNTAINS. SNOW LEVELS ARE
AT AROUND 7000 FEET CURRENTLY AND COULD FALL TO 5500-6000 FEET
THIS EVENING...WITH A TRACE TO AN INCH OF SNOW POSSIBLE. WITH THE
STRONG AND COOL ONSHORE FLOW AND THE LOW JUST TO OUR NORTH...HIGHS
TODAY WILL FALL TO 10-20 DEGREES BELOW NORMAL FOR MOST OF THE
AREA.
A TRANSITORY WEAK UPPER RIDGE SHOULD BRING SLIGHT WARMING TUESDAY
AND WEDNESDAY...WITH HIGHS A FEW TO SEVERAL DEGREES BELOW NORMAL.
MODELS CONTINUE TO SHOW A LOW MOVING DOWN FROM THE NORTH LATE
WEDNESDAY THROUGH THURSDAY...CREATING A MORE SIGNIFICANT COOL-
DOWN...INCREASING CLOUDS...ANOTHER ROUND OF STRONG AND GUSTY
WINDS IN THE MOUNTAINS AND DESERTS AND LIKELY PRODUCING AREAS OF
LIGHT TO MODERATE SHOWERS. MODEL SOLUTIONS BRING THE COLD CORE OF
THE LOW CLOSE TO...OR OVER...SOUTHERN CALIFORNIA...SO SOME LOCALLY
HEAVIER SHOWERS AND/OR THUNDERSTORMS ARE A POSSIBILITY. FORECAST
STORM TOTAL PRECIPITATION AMOUNTS LOOK TO BE LIGHT TO LOCALLY
MODERATE...WITH A TRACE TO 0.10 INCHES IN THE COASTAL AND DESERT
AREAS...0.05 TO 0.25 INCHES IN THE VALLEYS...AND 0.25 TO 0.50
INCHES IN THE MOUNTAINS. SNOW LEVELS LOWER TO AROUND 6500-7500
FEET WITH A FEW INCHES OF SNOW POSSIBLE ABOVE THAT ELEVATION. 850
MB WINDS ONLY INCREASE TO ABOUT 15-20 KT...AND ONSHORE PRESSURE
GRADIENTS FROM SAN DIEGO TO LAS VEGAS INCREASE TO ONLY ABOUT 7-10
MB...SO EXPECT A WEAKER WIND EVENT THAN THE ONE WE ARE
EXPERIENCING TODAY.
THERE MAY BE A FEW LINGERING SHOWERS FRIDAY AS THE TROUGH SLOWLY
MOVES EAST. MODELS ARE IN GENERAL AGREEMENT WITH DRY AND WARMER
WEATHER FOR SATURDAY AND SUNDAY WITH RIDGING NUDGING EASTWARD INTO
THE WEST COAST AND NORTHERLY FLOW ALOFT.
&&
.AVIATION...
252030...COAST/VALLEYS...SCT TO BKN CIGS WITH CLOUD BASES BETWEEN
2000 AND 3000 FT MSL AND TOPS NEAR 4500 FT MSL WILL GRADUALLY BECOME
FEW TO SCT WITH BASES NEAR 3000 FT MSL THIS AFTERNOON. WESTERLY
WINDS WILL REMAIN GUSTY THROUGH 03Z...WITH SUSTAINED WINDS 10 TO 20
KTS AND GUSTS 20 TO 25 KTS. OCCASIONAL GUSTS TO 30 KTS ARE POSSIBLE
OVER THE INLAND EMPIRE. SCT TO BKN LOW CLOUDS WITH BASES NEAR 2500
FT MSL WILL REDEVELOP AFTER 03Z...WITH THE GREATEST COVERAGE
EXPECTED OVER SD COUNTY.
MOUNTAINS/DESERTS...VERY WINDY CONDITIONS WILL CONTINUE OVER THE
MOUNTAINS AND DESERTS THROUGH THIS EVENING...WITH WEST TO NORTHWEST
WINDS SUSTAINED AT 10 TO 30 KTS...GUSTING 35 TO 50 KTS. LOCAL GUSTS
IN EXCESS OF 55 KTS WILL BE POSSIBLE THROUGH THE PASSES AND ALONG
THE DESERT SLOPES OF THE MOUNTAINS. THE STRONGEST WINDS ARE EXPECTED
TO OCCUR THROUGH 03Z TUESDAY. WINDS OF THIS MAGNITUDE WILL PRODUCE
AREAS OF BLOWING DUST AND SAND...ALONG WITH STRONG UDDFS AND LLWS.
ROTORS MAY ALSO DEVELOP IN THE LEE OF THE MOUNTAINS. ISOLATED LIGHT
SHOWER ACTIVITY IS POSSIBLE OVER THE MOUNTAINS THROUGH 06Z
TUESDAY...AND MAY PRODUCE LOCALLY REDUCED VISIBILITIES.
&&
.MARINE...
130 PM...GALE FORCE CONDITIONS WILL PERSIST OVER THE COASTAL
WATERS INTO TONIGHT. NORTHWEST WINDS WILL BE SUSTAINED AT 15 TO 30
KTS WITH GUSTS 25 TO 40 KTS. A STEEP NORTHWEST SWELL WILL
ACCOMPANY THE WINDS...RESULTING IN COMBINED SEAS OF 9 TO 14
FT...WITH LOCAL SEAS TO 16 FT NEAR AND SOUTHWEST OF SAN CLEMENTE
ISLAND. THE WINDS WILL FALL BELOW GALE FORCE TUESDAY...HOWEVER THE
SEAS WILL REMAIN STEEP. ANOTHER PERIOD OF GUSTY WINDS WILL ARRIVE
WEDNESDAY INTO THURSDAY WITH LIGHT SHOWER ACTIVITY POSSIBLE
THURSDAY. LOWERING SEAS AND LIGHTER WINDS ARE EXPECTED FRIDAY
THROUGH THE WEEKEND. PLEASE SEE THE GALE WARNING...LAXMWWSGX...FOR
MORE DETAILS.
&&
.BEACHES...
130 PM...A LARGE...BUT SHORT PERIOD NORTHWEST SWELL WILL CONTINUE TO
IMPACT THE BEACHES THROUGH TONIGHT. WHEN COMBINED WITH THE
WINDS...THIS WILL RESULT IN CHOPPY 3 TO 5 FT SURF AT THE BEACHES
WITH LOCAL SETS TO 6 FT POSSIBLE OVER SOUTHERN SD COUNTY. STRONG RIP
CURRENTS WILL BE POSSIBLE AS WELL. PLEASE SEE THE BEACH HAZARD
STATEMENT...LAXCFWSGX...FOR ADDITIONAL DETAILS.
&&
.SKYWARN...
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...WIND ADVISORY UNTIL 11 PM PDT THIS EVENING FOR RIVERSIDE COUNTY
MOUNTAINS-SAN BERNARDINO COUNTY MOUNTAINS-SAN DIEGO COUNTY
MOUNTAINS.
HIGH WIND WARNING UNTIL 11 PM PDT THIS EVENING FOR APPLE AND
LUCERNE VALLEYS-COACHELLA VALLEY-SAN DIEGO COUNTY DESERTS-
SAN GORGONIO PASS NEAR BANNING.
WIND ADVISORY UNTIL 9 PM PDT THIS EVENING FOR ORANGE COUNTY
COASTAL AREAS-ORANGE COUNTY INLAND AREAS-SAN BERNARDINO AND
RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-SAN DIEGO COUNTY
COASTAL AREAS-SAN DIEGO COUNTY VALLEYS-SANTA ANA MOUNTAINS
AND FOOTHILLS.
BEACH HAZARDS STATEMENT THROUGH TUESDAY EVENING FOR ORANGE
COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS.
PZ...GALE WARNING UNTIL 11 PM PDT THIS EVENING 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...HARRISON
AVIATION/MARINE/BEACHES...BA
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
922 AM PDT MON APR 25 2016
.SYNOPSIS...
MOSTLY CLOUDY AND COOL TODAY WITH STRONG AND GUSTY WEST
WINDS...AND ISOLATED LIGHT SHOWERS OVER AND WEST OF THE MOUNTAINS.
DRY AND A LITTLE WARMER FOR TUESDAY AND MOST OF WEDNESDAY UNDER
WEAK HIGH PRESSURE ALOFT. SIGNIFICANT COOLING AGAIN FOR LATE
WEDNESDAY AND THURSDAY WITH A CHANCE FOR SHOWERS AND MOUNTAIN
SNOW...ALONG WITH GUSTY WEST WINDS IN THE MOUNTAINS AND DESERTS.
THE SHOWERS TAPER OFF ON FRIDAY...BUT CONDITIONS REMAIN COOL
BEFORE WARMING NEXT WEEKEND AS A HIGHER PRESSURE ALOFT STARTS TO
NUDGE INTO THE WEST.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
WATER VAPOR SATELLITE SHOWS A LOW PRESSURE SYSTEM ROTATING OVER
NEVADA...AND A VORT MAX IS NOTED OVER NORTHERN CALIFORNIA. THE 12Z
MIRAMAR SOUNDING SHOWED 850 MB WESTERLY WINDS OF 35 KT...WHICH IS
A LITTLE STRONGER THAN MODELS INDICATED. ONSHORE PRESSURE
GRADIENTS ARE ALSO STRONGER THAN THE MODELS SHOWED...AS THEY ARE
CURRENTLY 14 MB FROM SAN DIEGO TO LAS VEGAS...AND 7.3 MB FROM SAN
DIEGO TO THERMAL. CURRENTLY...WINDS IN AT MOUNTAIN RIDGES...DESERT
SLOPES AND ADJACENT DESERTS ARE GUSTING TO 30-40 MPH. THE
AFOREMENTIONED VORT MAX WILL ROTATE AROUND THE LOW AND INTO
SOUTHERN CALIFORNIA LATER TODAY AND THIS EVENING...CREATING
STRONGER WINDS IN ALL AREAS...PARTICULARLY ALONG THE DESERT SLOPES
AND INTO THE DESERTS WHERE 35-45 KT SUSTAINED WINDS ALOFT COULD
SURFACE. WINDS SHOULD STRENGTHEN BY LATE MORNING ACCORDING TO HI-
RES MODELS AND MOS GUIDANCE. IN FACT...GFS MOS GUIDANCE SHOWS WIND
GUSTS OF 55 MPH POSSIBLE AT PALM SPRINGS BY EARLY AFTERNOON. IF
THESE STRONG WINDS SURFACE IN THE DESERTS...IMPACTS SUCH AS
POSSIBLE STRUCTURAL DAMAGE AND NEAR ZERO VISIBILITY DUE TO BLOWING
SAND/DUST WOULD BE POSSIBLE. THUS...HAVE UPGRADED TO A HIGH WIND
WARNING FOR THE DESERTS. WIND ADVISORIES REMAIN IN EFFECT FOR ALL
OTHER AREAS. WINDS WILL DIMINISH LATE TONIGHT INTO TUESDAY MORNING
AS THE WAVE MOVES TO THE EAST.
MEANWHILE...THERE HAVE BEEN ISOLATED SHOWERS PRODUCING LIGHT
PRECIPITATION AMOUNTS IN THE MOUNTAINS...WITH THE SAN BERNARDINO
COUNTY MOUNTAINS...AND THE SAN GORGONIO WILDERNESS IN
PARTICULAR...GETTING THE MAJORITY OF THE SHOWER ACTIVITY...WHERE
NEAR A HALF INCH AND UP TO 0.91 INCHES HAVE FALLEN. THERE WERE
ALSO SOME REPORTS OF A DUSTING OF SNOW UP IN THE BIG BEAR AREA.
CURRENTLY THERE IS STILL A LINE OF LIGHT SHOWERS IN THE SAN
GORGONIO WILDERNESS AREA...BUT NOT MUCH ELSEWHERE. THE HRRR SHOWS
SHOWERS CONTINUING TO DISSIPATE THIS MORNING...WITH SHOWERS THEN
RE-DEVELOPING OVER THE SAN BERNARDINO COUNTY MOUNTAINS AND INTO
THE RIVERSIDE COUNTY MOUNTAINS/DESERTS LATE THIS AFTERNOON INTO
THE EVENING AS THE UPPER LEVEL WAVE MOVES THROUGH. ADDITIONAL
PRECIPITATION AMOUNTS OF 0.05-0.25 INCHES COULD OCCUR IN THE
MOUNTAINS. SNOW LEVELS ARE AT AROUND 6000-6500 FEET CURRENTLY AND
COULD FALL TO 5500-6000 FEET TODAY...WITH A TRACE TO AN INCH OF
SNOW POSSIBLE. WITH THE STRONG AND COOL ONSHORE FLOW AND THE LOW
JUST TO OUR NORTH...HIGHS TODAY WILL FALL TO 10-20 DEGREES BELOW
NORMAL FOR MOST OF THE AREA.
A TRANSITORY WEAK UPPER RIDGE SHOULD BRING SLIGHT WARMING TUESDAY
AND WEDNESDAY...WITH HIGHS A FEW TO SEVERAL DEGREES BELOW NORMAL.
MODELS CONTINUE TO SHOW A LOW MOVING DOWN FROM THE NORTH LATE
WEDNESDAY THROUGH THURSDAY...CREATING A MORE SIGNIFICANT COOL-
DOWN...INCREASING CLOUDS...GUSTY WINDS IN THE MOUNTAINS AND
DESERTS AND POTENTIALLY PRODUCING PERIODS OF LIGHT TO MODERATE
SHOWERS. MODEL SOLUTIONS BRING THE COLD CORE OF THE LOW CLOSE
TO...OR OVER...SOUTHERN CALIFORNIA...SO SOME LOCALLY HEAVIER
SHOWERS AND/OR THUNDERSTORMS ARE A POSSIBILITY. SNOW LEVELS LOWER
TO AROUND 6500-7500 FEET WITH A FEW INCHES OF SNOW POSSIBLE ABOVE
THAT ELEVATION.
THERE MAY BE A FEW LINGERING SHOWERS FRIDAY AS THE TROUGH SLOWLY
MOVES EAST. MODELS ARE IN GENERAL AGREEMENT WITH DRY AND WARMER
WEATHER FOR SATURDAY AND SUNDAY WITH RIDGING NUDGING EASTWARD INTO
THE WEST COAST AND NORTHERLY TO NORTHWEST FLOW ALOFT.
&&
.AVIATION...
251530...COAST/VALLEYS...BKN CIGS WITH CLOUD BASES BETWEEN 2000 AND
3500 FT MSL AND TOPS NEAR 4500 FT MSL THIS MORNING...WILL GRADUALLY
BECOME SCT WITH BASES NEAR 3000 FT MSL AFTER 17Z. WESTERLY WINDS
WILL INCREASE AFTER 17Z...WITH SUSTAINED WINDS 10 TO 20 KTS AND
GUSTS 20 TO 25 KTS. OCCASIONAL GUSTS TO 30 KTS ARE POSSIBLE OVER THE
INLAND EMPIRE. THE WINDS WILL BEGIN TO DECREASE BY 03Z TUESDAY.
LOCALLY REDUCED VIS DUE TO LIGHT SHOWER ACTIVITY IS POSSIBLE OVER
THE VALLEYS THROUGH 18Z.
MOUNTAINS/DESERTS...VERY WINDY CONDITIONS ARE EXPECTED OVER THE
MOUNTAINS AND DESERTS TODAY...WITH WEST TO NORTHWEST WINDS SUSTAINED
AT 10 TO 30 KTS...GUSTING 35 TO 50 KTS. LOCAL GUSTS IN EXCESS OF 55
KTS WILL BE POSSIBLE THROUGH THE PASSES AND ALONG THE DESERT SLOPES
OF THE MOUNTAINS. THE STRONGEST WINDS ARE EXPECTED TO OCCUR THROUGH
03Z TUESDAY. WINDS OF THIS MAGNITUDE WILL PRODUCE AREAS OF BLOWING
DUST AND SAND...ALONG WITH STRONG UDDFS AND LLWS. ROTORS MAY ALSO
DEVELOP IN THE LEE OF THE MOUNTAINS. ISOLATED LIGHT SHOWER ACTIVITY
IS POSSIBLE OVER THE MOUNTAINS THROUGH THIS EVENING...AND MAY
PRODUCE LOCALLY REDUCED VISIBILITIES.
&&
.MARINE...
830 AM...GALE FORCE CONDITIONS WILL PERSIST OVER THE COASTAL WATERS
INTO TONIGHT. NORTHWEST WINDS WILL BE SUSTAINED AT 15 TO 30 KTS WITH
GUSTS 25 TO 40 KTS. A STEEP NORTHWEST SWELL WILL ACCOMPANY THE
WINDS...RESULTING IN COMBINED SEAS OF 9 TO 14 FT...WITH LOCAL SEAS
TO 16 FT NEAR AND SOUTHWEST OF SAN CLEMENTE ISLAND. THE WINDS WILL
FALL BELOW GALE FORCE TUESDAY...HOWEVER THE SEAS WILL REMAIN STEEP.
ANOTHER PERIOD OF GUSTY WINDS WILL ARRIVE WEDNESDAY INTO THURSDAY
WITH LIGHT SHOWER ACTIVITY POSSIBLE THURSDAY. LOWERING SEAS AND
LIGHTER WINDS ARE EXPECTED FRIDAY THROUGH THE WEEKEND. PLEASE SEE
THE GALE WARNING...LAXMWWSGX...FOR MORE DETAILS.
&&
.BEACHES...
830 AM...A LARGE...BUT SHORT PERIOD NORTHWEST SWELL WILL CONTINUE TO
IMPACT THE BEACHES THROUGH TONIGHT. WHEN COMBINED WITH THE
WINDS...THIS WILL RESULT IN CHOPPY 3 TO 5 FT SURF AT THE BEACHES
WITH LOCAL SETS TO 6 FT POSSIBLE OVER SOUTHERN SAN DIEGO COUNTY.
STRONG RIP CURRENTS WILL BE POSSIBLE AS WELL. PLEASE SEE THE BEACH
HAZARD STATEMENT...LAXCFWSGX...FOR ADDITIONAL DETAILS.
&&
.SKYWARN...
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...WIND ADVISORY UNTIL 11 PM PDT THIS EVENING FOR RIVERSIDE COUNTY
MOUNTAINS-SAN BERNARDINO COUNTY MOUNTAINS-SAN DIEGO COUNTY
MOUNTAINS.
HIGH WIND WARNING UNTIL 11 PM PDT THIS EVENING FOR APPLE AND
LUCERNE VALLEYS-COACHELLA VALLEY-SAN DIEGO COUNTY DESERTS-
SAN GORGONIO PASS NEAR BANNING.
WIND ADVISORY FROM NOON TODAY TO 9 PM PDT THIS EVENING FOR
ORANGE COUNTY COASTAL AREAS-ORANGE COUNTY INLAND AREAS-SAN
BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-
SAN DIEGO COUNTY COASTAL AREAS-SAN DIEGO COUNTY VALLEYS-
SANTA ANA MOUNTAINS AND FOOTHILLS.
BEACH HAZARDS STATEMENT THROUGH TUESDAY EVENING FOR ORANGE
COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS.
PZ...GALE WARNING UNTIL 11 PM PDT THIS EVENING 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...HARRISON
AVIATION/MARINE/BEACHES...BA
AREA FORECAST DISCUSSION
NWS TAUNTON MA
159 PM EDT MON APR 25 2016
.SYNOPSIS...
HIGH PRESSURE FROM CENTRAL CANADA TO NEW ENGLAND WILL REMAIN NEARLY
STATIONARY TODAY PROVIDING DRY AND SEASONABLY WARM WEATHER TO THE
AREA. A WAVE OF LOW PRESSURE WILL TRACK JUST SOUTH OF NEW ENGLAND
TUE PROVIDING A WIDESPREAD APPRECIABLE RAINFALL TO THE REGION ALONG
WITH A CHILLY NORTHEAST WIND AND MUCH COOLER THAN NORMAL TEMPS. HIGH
PRESSURE BUILDS ACROSS THE REGION WEDNESDAY. ANOTHER LOW PRESSURE
CENTER WILL QUICKLY PASS SOUTH OF NEW ENGLAND THURSDAY NIGHT INTO
EARLY FRIDAY. HIGH PRESSURE MOVES OUT OF CENTRAL CANADA LATE
FRIDAY...BRINGING DRY BUT COOL CONDITIONS THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
200 PM UPDATE...
LATEST VISIBLE SATELLITE IMAGERY SHOWS BREAKS IN THE CLOUD DECK
WHICH WILL HELP INCREASE SURFACE TEMPS ACROSS SOUTHERN NEW ENGLAND
THIS AFTERNOON. HOWEVER ONSHORE FLOW FOR COASTLINES HAVE KEPT
TEMPS INTO THE LOW 50S. OTHERWISE MAINLY DRY WEATHER DAY INTO THE
AFTERNOON. WATCHING A BATCH OF PRECIP MOVING ACROSS UPDATE NEW
YORK. LATEST HRRR GUIDANCE TRIES TO BRING THIS OVER AROUND 21/22Z.
IF THAT OCCURS THEN ANTICIPATE EITHER VIRGA OR SPRINKLES AS LOW
LEVELS ARE STILL QUITE DRY PER BUFKIT SOUNDINGS. MADE A FEW MINOR
TWEAKS TO THE FORECAST BUT OTHERWISE THE BULK OF THE FORECAST
REMAINS ON TRACK.
PREVIOUS DISCUSSION...
MID LEVEL MOISTURE FROM CLOSED LOW OVER SOUTH DAKOTA THIS MORNING
CONTINUES TO STREAM EAST-SOUTHEAST IN THE CONFLUENT FLOW OVER THE
GREAT LAKES INTO THE NORTHEAST. THIS WILL RESULT IN INCREASING MID
AND HIGH CLOUDS ACROSS SOUTHERN NEW ENGLAND AS THE DAY PROGRESSES.
ALTHOUGH LATE APRIL SUN ANGLE MAY BE HIGH ENOUGH TO YIELD AT LEAST
DIM SUNSHINE THRU THE CLOUD COVER.
REGARDING HIGH TEMPS THIS AFTERNOON...GIVEN SURFACE PRESSURES
ACROSS THE AREA ARE ONLY ABOUT 1015 MB...THIS PROMOTES A DEEP
BLYR WITH MDL SNDGS SUGGESTING MIXING TO 800 MB. THIS COMBINED
WITH 850 MB TEMPS AROUND +2C WILL SUPPORT HIGHS IN THE LOW TO MID
60S AWAY FROM COASTAL SEABREEZES. MAY HAVE TO SHAVE A FEW DEGS OFF
THESE HIGHS IF MID DECK OF CLOUDS REMAINS PERSISENT. SO OVERALL A
PLEASANT DAY BY LATE APRIL STANDARDS WITH DIM SUNSHINE THRU
MID/HIGH CLOUDS...LIGHT WINDS AND TEMPS IN THE LOW TO MID 60S AWAY
FROM THE IMMEDIATE COASTLINE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
*** MUCH NEEDED WIDESPREAD APPRECIABLE RAINFALL TUE ALONG WITH
MUCH COOLER THAN NORMAL TEMPS ***
AS CLOSED LOW OVER SOUTH DAKOTA BECOMES AN OPEN WAVE...LOW PRES
TRACKS FROM THE GREAT LAKES TONIGHT TO SOUTH OF THE NEW ENGLAND TUE.
MODEST PWAT PLUME TO WORK WITH AS ANOMALIES ARE ABOUT +1 STANDARD
DEVIATIONS ABOVE CLIMO. FAIRLY BAROCLINIC WAVE BY LATE APRIL
STANDARDS ALONG WITH MODEST FGEN. HOWEVER NAM AND GFS DIFFER ON
LOCATION AND MAGNITUDE OF FGEN WHICH IS TYPICAL AT THIS TIME RANGE.
NONETHELESS DEEP LAYER MOISTURE...SYNOPTIC SCALE LIFT AND FRONTAL
SCALE FORCING WILL YIELD A WIDESPREAD RAIN WITH APPRECIABLE QPF.
TIMING...DEEP LAYER OF DRY AIR CURRENTLY IN PLACE ACROSS SOUTHERN
NEW ENGLAND WILL LIKELY DELAY THE ONSET OF RAIN AROUND OR AFTER
MIDNIGHT TONIGHT. GFS AND ITS ENSEMBLES ARE ON THE FAST EDGE OF THE
GUID ENVELOPE WITH PRECIP ARRIVING AFTER 21Z TODAY ACROSS HFD-BAF.
WHILE THIS IS POSSIBLE ANY RAIN AFTER 21Z WILL BE VERY LIGHT AND
SPOTTY. HEAVIEST/STEADIEST RAINFALL OCCURS DURING THE DAY TUE. SOME
MODEL SPREAD/UNCERTAINTY ON DEPARTURE OF RAIN. GFS THE FASTEST WITH
PRECIP ENDING LATE TUE AFTN WITH REMAINDER OF GUID SUPPORTING TUE
EVENING OR OVERNIGHT.
PTYPE...DESPITE SUB FREEZING 925 MB AND 850 TEMPS ACROSS NORTHERN MA
LATER TUE...WARM LAYER ABOVE 850 MB WILL YIELD A COLD RAIN FOR THE
REGION. HOWEVER AS THIS WARM LAYER BEGINS TO ERODE LATER TUE RAIN
MAY MIX WITH SLEET AND/OR SNOW BEFORE ENDING ACROSS NORTHERN MA.
ANY BRIEF CHANGEOVER TO SLEET AND/OR SNOW WILL HINGE ON PRECIP
INTENSITY AND ASSOCIATED DIABATIC COOLING/MELTING. WILL NEED TO
WATCH THIS CLOSELY. YES...IT/S STILL APRIL IN NEW ENGLAND.
TEMPS...CHILLY AIRMASS ON POLEWARD SIDE OF THIS FRONTAL BOUNDARY.
COMBINATION OF PRECIP...LOW WETBULB TEMPS AND NORTHEAST WINDS WILL
YIELD TEMPS WELL BELOW NORMAL. THUS BLENDED IN THE COLDER MODEL 2
METER TEMPS AND THIS YIELDS HIGHS ONLY IN THE U30S FOR THE HIGHER
TERRAIN INCLUDING WORCESTER. NOT MUCH WARMER ELSEWHERE WITH HIGHS IN
THE 40S BUT FEELING COOLER ESPECIALLY EASTERN MA WITH NE WINDS 15-20
MPH OFF THE COOL OCEAN WATERS.
QPF...GIVEN EVENT IS STILL 36+ HRS AWAY FOLLOWED A MODEL BLEND WHICH
OFFERS 0.25 TO 0.75 INCHES. GEFS HAS 70% AND GREATER PROBS FOR 0.50
INCH OF QPF. IN ADDITION GEFS MEAN CENTERED AROUND 0.50 INCHES.
THUS APPRECIABLE RAINFALL EXPECTED HOWEVER DIFFICULT AT THIS TIME
RANGE TO PINPOINT EXACT LOCATION OF HEAVIER MESOSCALE RAIN BANDS.
IN ADDITION GFS AND NAM SUGGEST SOME UPSLOPE ENHANCEMENT POSSIBLE
TUE MORNING ACROSS THE EAST SLOPES OF THE BERKSHIRES INTO NORTHWEST
HARTFORD COUNTY. NEVERTHELESS BENEFICIAL RAINS FOR THE ENTIRE REGION.
THUNDER POTENTIAL...WITH FRONTAL WAVE TRACKING SOUTH OF NEW ENGLAND
WARM SECTOR WILL REMAIN OFFSHORE. HOWEVER MARGINAL ELEVATED
INSTABILITY ACROSS THE SOUTH COAST. THUS HAVE KEPT SLIGHT CHANCE OF
THUNDER FROM PREVIOUS FORECAST BUT CONFINED TO SOUTH COAST INCLUDING
CAPE COD AND THE ISLANDS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
OVERVIEW...
H5 CUTOFF LOW PRESSURE/COLD POOL WILL CONTINUE TO LINGER ACROSS
NORTHERN QUEBEC AND LABRADOR THROUGH THE LATTER PORTIONS OF THE
WORK WEEK...KEEPING THE REGION IN A W-NW CYCLONIC WIND FLOW. A
COUPLE OF SHORT WAVES WILL EJECT OUT OF THE UPPER PLAINS...PUSHING
QUICKLY ACROSS THE REGION...FIRST LATE TUE NIGHT INTO WED...THEN
A SECOND FRI INTO SAT. LOWERED H5 HEIGHTS WILL KEEP TEMPERATURES
GENERALLY NEAR OR JUST BELOW SEASONAL LEVELS.
THE CANADIAN CUTOFF UPPER LOW LOOKS TO SLOWLY EXIT TO GREENLAND
BY THIS WEEKEND...BUT THE W-NW FLOW WILL LINGER. LARGE HIGH PRES
OUT OF CENTRAL CANADA WILL EXPAND INTO THE NORTHEAST...BRINGING
DRY AND NEAR SEASONABLE CONDITIONS FOR THE UPCOMING WEEKEND. SOME
QUESTIONS ABOUT A SOUTHERN STREAM SYSTEM THAT MAY PUSH FAR ENOUGH
N TO BRING SOME PRECIPITATION LATE THIS WEEKEND...BUT TIMING IS
VERY MUCH IN QUESTION.
DETAILS...
TUESDAY NIGHT...
LEFTOVER SHOWERS WILL PUSH OFF THE S COAST TUE EVENING AS NOSE OF
HIGH PRES RIDGE BUILDS SE OUT OF N NY/CENTRAL CANADA. MOST OF THE
SHOWERS SHOULD BE OFFSHORE BY MIDNIGHT...BUT A FEW MAY LINGER
ACROSS S COASTAL AREAS A FEW HOURS LONGER. MIGHT SEE A FEW SPOTTY
LIGHT SNOW SHOWERS OR EVEN A LITTLE SLEET AS THE PRECIP ENDS
ACROSS THE HIGHER TERRAIN OF N CENTRAL AND W MA...BUT THIS WILL
NOT LAST LONG.
LEFTOVER GUSTS UP TO 20-25 MPH ALONG THE S COAST WILL DIMINISH
TUE EVENING. OTHERWISE...EXPECT SKIES TO BECOME PARTLY CLOUDY
ACROSS MOST AREAS...WITH MORE CLOUDS LINGERING ALONG THE S COAST
INTO THE PRE DAWN HOURS BEFORE MOVING OFFSHORE.
AS COLDER AIR FILTERS IN...TEMPS WILL FALL BACK TO THE 30S...AND
MIGHT EVEN SEE SOME READINGS IN THE UPPER 20S ACROSS THE HIGHER
INLAND TERRAIN. WILL HAVE TO WATCH OUT FOR POSSIBLE FROST IN SOME
AREAS WHERE THE GROWING SEASON HAS ALREADY BEGUN...NAMELY PORTIONS
OF COASTAL ESSEX COUNTY AS WELL AS INTERIOR SE MA...N RI AND NE
CT.
WEDNESDAY...
HIGH PRESSURE RIDGING BUILDS ACROSS THE REGION SO WILL SEE DRY
CONDITIONS AND MAINLY SUNNY SKIES. LOCAL SEA BREEZES WILL LIKELY
DEVELOP DURING THE AFTERNOON. TEMPS WILL ONLY RISE TO THE TO THE
LOWER 50S ACROSS THE HIGHER INLAND TERRAIN AS WELL AS THE CAPE
AND ISLANDS...RANGING TO AROUND 60 ACROSS THE LOWER CT VALLEY.
SKIES WILL REMAIN MOSTLY CLEAR THROUGH MOST OF WED NIGHT...THEN
SOME CLOUDS WILL START TO WORK INTO N CENTRAL CT TOWARD DAYBREAK.
WITH LIGHT/VRBL WINDS...WILL SEE GOOD RADIATIONAL COOLING AGAIN
WITH DEWPTS LOWERING TO THE UPPER TEENS AND 20S AWAY FROM THE
COAST. MAY SEE TEMPS BOTTOM OUT AROUND 20 DEGREES ALONG THE E
SLOPES OF THE BERKSHIRES...RANGING TO THE LOWER-MID 30S ALONG THE
S COAST.
THURSDAY-FRIDAY...
WITH FAST MOVING FLOW ALOFT CONTINUING...WILL SEE ANOTHER H5
SHORT WAVE PUSH TOWARD THE REGION. SOME TIMING ISSUES AMONGST THE
00Z MODEL SUITE...BUT LOOKS LIKE THE NORTHERN EDGE OF PRECIP FROM
FAST MOVING LOW PRES PASSING S OF NEW ENGLAND WILL MOVE IN THU
AFTERNOON...WITH THE BEST CHANCE FOR SHOWERS ALONG THE S COAST THU
NIGHT. WINDS BECOME LIGHT E-NE...SO WILL NOT BE AS COLD THU NIGHT
SO EXPECT PRECIP TO BE MAINLY RAIN. KEPT LOW CHANCE GOING AT MOST.
THE LOW WILL PUSH OFFSHORE BY MID MORNING FRIDAY...THEN
CONDITIONS IMPROVE FROM N-S DURING THE DAY. TEMPS WILL RISE TO
NEAR SEASONABLE LEVELS...TOPPING OFF IN THE UPPER 50S TO MID
60S...EXCEPT REMAINING COOLER ALONG THE IMMEDIATE COAST.
SATURDAY-SUNDAY...
SOUTHERN EXTENT OF LARGE HIGH PRES BUILDS SE OUT OF CENTRAL
CANADA. MODELS TENDING TO KEEP DRY AND COOL CONDITIONS ACROSS THE
REGION THROUGH THE WEEKEND.
DO NOTE THE 00Z ECMWF BRINGS MOISTURE INTO THE REGION SUNDAY
NIGHT FROM A SOUTHERN STREAM LOW PRES CENTER ACROSS THE OHIO
VALLEY. LOW CONFIDENCE WITH THIS FEATURE THIS FAR OUT SO KEPT DRY
AND COOL CONDITIONS GOING FOR NOW.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY NIGHT/...HIGH CONFIDENCE.
BEFORE 00Z...VFR. A FEW SPRINKLES POSSIBLE.
TONIGHT...VFR TO START BUT LOWERING TO MVFR TOWARD MORNING WITH
RAIN /MAINLY LIGHT/ BECOMING WIDESPREAD AFTER 06Z.
TUESDAY...MVFR BECOMING WIDESPREAD WITH IFR POSSIBLE OVER EASTERN
MA. STEADY RAIN WITH EMBEDDED MODERATE TO HEAVY RAIN AT TIMES. NE
WINDS INCREASING TO 15 TO 20 KT ACROSS EASTERN MA WITH GUSTS UP TO
25 KT POSSIBLE. LOW POSSIBILITY FOR THUNDER ACROSS THE ISLANDS.
TUESDAY NIGHT...MVFR/IFR TO START WITH CONDITIONS IMPROVING
THROUGH THE NIGHT TO VFR.
KBOS TAF...HIGH CONFIDENCE FOR VFR AND DRY WEATHER. LIGHT S-SW
WIND WILL BECOME E-SE EARLY THIS AFTERNOON.
KBDL TAF...HIGH CONFIDENCE FOR VFR AND DRY WEATHER. LOW RISK OF
SOME VERY LIGHT RAIN/SPRINKLES AFTER 21Z WITH STEADIER RAIN
ARRIVING AROUND 06Z TONIGHT.
OUTLOOK /WEDNESDAY THROUGH FRIDAY/...
WEDNESDAY...HIGH CONFIDENCE. VFR.
THURSDAY...MODERATE CONFIDENCE.
VFR EARLY THU...THEN AREAS OF MVFR CIGS/VSBYS MAINLY S OF THE
MASS PIKE IN SHOWERS AND PATCHY FOG. LOW CHANCE FOR LOCAL IFR
CONDITIONS MAINLY THU NIGHT. IMPROVING FROM N-S AFTER MIDNIGHT.
FRIDAY...MODERATE TO HIGH CONFIDENCE.
LEFTOVER MVFR CIGS/VSBYS ALONG THE S COAST EARLY...THEN
IMPROVING. OTHERWISE...VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...HIGH CONFIDENCE.
TODAY ... LIGHT WINDS WITH HIGH PRES OVERHEAD. DRY WEATHER AND
GOOD VSBY TOO.
TONIGHT ... WINDS BECOMING ENE LATE AS LOW PRES ENTERS PA. RAIN
OVERSPREADS RI WATERS LATE.
TUE ... LOW PRES TRACKS JUST SOUTH OF NEW ENGLAND. THIS WILL
YIELD AN INCREASE IN ENE WINDS OF 15 TO 20 KT WITH LOW RISK OF A
FEW 25 KT GUSTS VICINITY OF CAPE COD AND NANTUCKET WATERS EASTWARD
TOWARDS WESTERN GEORGES BANK. WIDESPREAD RAIN AND AREAS OF FOG
LIMIT VSBY.
OUTLOOK /TUESDAY NIGHT THROUGH FRIDAY/...MODERATE CONFIDENCE.
TUESDAY NIGHT...
NE WINDS GUSTING TO 20-25 KT ACROSS THE EASTERN WATERS EARLY...
THEN WILL DIMINISH AS THEY BACK TO N-NW. SEAS UP TO 5-6 FT FROM
EAST OF CAPE COD TO ACROSS THE SOUTHERN WATERS WILL CONTINUE
THROUGH THE NIGHT. SMALL CRAFTS LIKELY NEEDED. REDUCED VSBYS IN
RAIN AND PATCHY FOG SHOULD IMPROVE BY AROUND MIDNIGHT FROM N-S.
WEDNESDAY...
N-NW WINDS AT 10-15 KT WILL SHIFT TO SW ACROSS THE SOUTHERN
WATERS AND MAY GUST TO 20 KT THERE. SEAS LINGER AT AROUND 5 FT
DURING WED...THEN WILL SUBSIDE WED NIGHT.
THURSDAY...
EXPECT LIGHT E-SE WINDS THU...SHIFTING TO S-SW ON THE EASTERN
WATERS THU NIGHT. SEAS 4 FT OR LESS. REDUCED VSBYS IN SCATTERED
SHOWERS AND PATCHY FOG ACROSS THE SOUTHERN WATERS AS WELL AS THE
WATER E OF CAPE COD.
FRIDAY...
WINDS SHIFT BACK TO E-NE ACROSS ALL WATERS BY FRI AFTERNOON...
THEN BECOME LIGHT AND VARIABLE FRI NIGHT. SEAS 3 FT OR LESS.
REDUCED VSBYS EARLY FRI IN SCT SHOWERS AND PATCHY FOG ON THE
SOUTHERN WATERS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...NOCERA/EVT
NEAR TERM...NOCERA/DUNTEN
SHORT TERM...NOCERA
LONG TERM...EVT
AVIATION...DUNTEN/EVT
MARINE...NOCERA/EVT
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
244 PM CDT MON APR 25 2016
.SHORT TERM...
227 PM CDT
THROUGH TUESDAY...
ANOTHER WARM AFTERNOON UNFOLDED ACROSS NORTHERN IL/NORTHWEST IN...AS
TEMPERATURES WERE ABLE TO QUICKLY PUSH INTO THE 70S WITH A FEW
LOCATIONS REACHING 80 DEGREES. THE LOW LEVEL SOUTHERLY FLOW ALSO
HELPED TO ADVECT ADDITIONAL MOISTURE INTO THE AREA WITH DEW POINTS
RISING INTO THE MID/UPR 50S. VISIBLE SATELLITE IMAGERY HAD SHOWN A
CHANNEL OF STRATUS STRETCHING FROM WESTERN WISC DOWN TO CENTRAL
MISSOURI...WITH WATER VAPOR IMAGERY SHOWING A SOME DRIER AIR IN THE
MID LEVELS LIFTING NORTH AHEAD OF THE STRATUS WHICH COULD FURTHER
AGITATE THE MID-LEVELS AFT 21Z. DCAPE THIS HAS BEGUN TO INCREASE AS
A RESULT OF THE DRY AIR ARRIVAL IN THE MID-LVLS ACROSS SOUTHEAST
IOWA/FAR WESTERN ILLINOIS. EFFECTIVE SHEAR CONTINUES TO INCREASE
WITH SOUTHERLY WINDS OVER NORTHERN IL AND WESTERLY FLOW OVER EASTERN
IOWA...ADDS TO THE LOW LEVEL CONVERGENCE/LIFT ZONE AS IT APPROACHES
NORTHERN IL LATER THIS AFTERNOON. CONVECTIVE ALLOWING MODELS
CONTINUE TO POINT TOWARDS INITIALIZATION ACROSS FAR WESTERN
ILLINOIS...THEN EXPECT CONVECTION TO REALIZE THE INSTABILITY THROUGH
THE COLUMN AND QUICKLY ADVANCE AND GROW BY 22-23Z.
ONCE CONVECTION GROWTH AND DEVELOPMENT OCCURS...THE MAIN HAZARDS FOR
SEVERE THREAT WILL CONTINUE TO BE ON DAMAGING WIND AND POSSIBLE
LARGE HAIL. THERE IS SOME INCREASED HELICITY AS THE BETTER
CONVERGENCE ZONE ARRIVES OVER NORTHERN IL THAT AN ISOLATED ROTATING
UPDRAFT COULD OCCUR...HOWEVER THE FOCUS CONTINUES TO BE WITH
DAMAGING WINDS FROM THE INCREASED DCAPE OF NEARLY 1000J/KG AND THE
STEADILY STEEPENING LAPSE RATES FOR LARGE HAIL.
BY 00Z OR SHORTLY AFTER 00Z...CONVECTION SHOULD BE OVER THE CHICAGO
METRO AREA BEGINNING TO TURN SOUTHEAST BASED ON THE VECTORS ALL
POINTING TOWARDS A SOUTHEAST ACROSS NORTHERN IL. THE FORWARD
PROPAGATION OF STORMS SHOULD BE AROUND 30-40KTS...WHICH WILL LIKELY
BRING A QUICK END TO THE CONVECTIVE/SEVERE CONCERNS OVER THE AREA BY
1-2Z. TEMPS TONIGHT WILL HINGE ON THE TIMING OF THE FRONTAL BOUNDARY
THAT IS SLIDING SOUTH ACROSS WISCONSIN BEHIND THE MID-LVL SHORTWAVE.
GUIDANCE HAS BEEN LEANING TOWARDS THIS FEATURE NOT ARRIVING UNTIL
AFTER MIDNIGHT AND PERHAPS JUST PRIOR TO DAYBREAK TUE. THIS WOULD
ALLOW TEMPS TO REMAIN MILD AGAIN TONIGHT IN THE 50S TO PERHAPS MID
40S ACROSS THE NORTHERN PORTIONS OF THE CWFA.
THEN FOR TUE BEHIND THE FRONT WINDS WILL TURN NORTHERLY TO
NORTHEASTERLY AS MUCH COOLER AIR ARRIVES. THERMAL TROUGH PUSHES
TEMPS ALOFT INTO THE 8 TO 11 DEG C...WHICH COUPLED WITH AN EXPECTED
STRATUS LAYER ARRIVING COULD HOLD HIGHS IN THE MID 50S TO MID
60S...THE EXCEPTION WILL BE THE FAR SOUTHERN CWFA WHERE TEMPS REMAIN
MILD ALONG THE BOUNDARY AND COULD WARM INTO THE MID 70S TUE AFTN.
WITH THE ONSHORE FLOW FOR AREAS ADJACENT TO LAKE MICHIGAN TEMPS WILL
STRUGGLE TO WARM BEYOND THE UPPER 40S TO LOW 50S.
BEACHLER
&&
.LONG TERM...
243 PM CDT
TUESDAY NIGHT THROUGH MONDAY...
A COOLER AND WETTER PATTERN IS EXPECTED...ESPECIALLY WEDNESDAY
AND THURSDAY...THEN AGAIN POSSIBLY OVER THE WEEKEND. THOUGH
UNCERTAINTY WITH THIS WEEKENDS POTENTIAL WET PERIOD IS HIGH AT
THIS TIME.
AN UPPER LEVEL TROUGH/LOW CURRENTLY NOTED IN WATER VAPOR IMAGERY
OVER THE SOUTHWESTERN CONUS...IS EXPECTED TO BE OUR MAIN WEATHER
MAKER WEDNESDAY INTO THURSDAY AS IT SHIFTS OVER THE LOWER GREAT
LAKES REGION IN A WEAKENING STATE. THIS IS STILL EXPECTED TO
PRODUCE PERIODS OF SHOWERS...AND POSSIBLY A FEW ELEVATED
THUNDERSTORMS...ESPECIALLY WEDNESDAY AFTERNOON INTO THURSDAY. NO
SEVERE WEATHER IS EXPECTED WITH THIS ACTIVITY.
PERSISTENT EAST-NORTHEASTERLY FLOW WITH EXTENSIVE CLOUD COVER AND
PRECIPITATION WILL LIKELY RESULT IN TEMPERATURES WEDNESDAY AND
THURSDAY ONLY IN THE LOW 50S INLAND AND NORTH OF INTERSTATE
80...IN THE 40S ON THE LAKE FRONT...AND IN TO 60S FAR SOUTH. WITH
DRIER WEATHER EXPECTED FOR FRIDAY...TEMPERATURES SHOULD REBOUND
BACK INTO THE LOWER 60S INLAND FROM LAKE MICHIGAN...BUT ONSHORE
FLOW WILL AGAIN RESULT IN COOLER CONDITIONS NEAR THE LAKE.
A SECOND STORM SYSTEM IS EXPECTED TO TAKE SHAPE OVER THE SOUTHERN
PLAINS LATE IN THE WEEK IN RESPONSE TO ANOTHER SOUTHWESTERN CONUS
TROUGH. THIS SYSTEM IS EXPECTED TO SHIFT EASTWARD OVER THE CENTRAL
CONUS OVER THE WEEKEND. HOWEVER...THERE IS A GOOD DEAL OF
UNCERTAINTY AT THIS TIME IN WHERE THIS SYSTEM WILL TRACK...AND AS
A RESULT HOW MUCH PRECIPITATION THIS SYSTEM COULD BRING US OVER
THE WEEKEND. AT THE PRESENT WE HAVE OPTED TO CONTINUE THE CHANCE
MENTION OF SHOWERS THROUGH MUCH OF THE WEEKEND UNTIL A BETTER
UNDERSTANDING OF THIS SYSTEMS EVOLUTION IS ACHIEVED.
KJB
&&
.AVIATION...
FOR THE 18Z TAFS...
VFR CONDS CONTINUE ACROSS NORTHERN IL/NORTHWEST IN
AIRFIELDS...HOWEVER THE FOCUS REMAINS ON POTENTIAL FOR CONVECTION
TO DEVELOP LATER THIS AFTERNOON THROUGH EARLY EVENING. WINDS WILL
REMAIN BREEZY FROM THE SOUTH TURNING SOUTHWEST AHEAD OF THE
CONVECTION...WITH SPEEDS GENERALLY AROUND 10 TO 15 KT AND GUSTS
BETWEEN 20 TO 25 KT AT TIMES. VISIBLE IMAGERY DOES SHOW A LAYER OF
CUMULUS CLOUDS DEVLEOPING WITH BASES AROUND 5-6KFT AGL...HOWEVER
AS OF MIDDAY THE VERTICAL GROWTH TO THE CUMULUS LAYER DOES NOT
LOOK TOO IMPRESSIVE...WHICH COULD DELAY THE TIMING FOR
SHOWERS/THUNDERSTORMS SLIGHTLY. GUIDANCE CONTINUES TO POINT
TOWARDS 22Z FOR DEVELOPMENT OF SHOWERS/THUNDERSTORMS WESTERN
IL...THEN QUICKLY INCREASEING IN INTENSITY BY 23Z AND APPROACHING
THE CHICAGO METRO TAF SITES. THE CONVECTION SHOULD BE PROGRESSIVE
AND PUSH EAST OF THE ORD/MDW SITES BY 00Z TO PERHAPS JUST AFTER
00Z...WITH CONVECTION ENDING BY 1Z TUE. THE FRONTAL BOUNDARY
REMAINS WELL NORTH/WEST OF THE AIRFIELDS...SO EXPECT ONCE
CONVECTION PUSHES THROUGH THAT WINDS WILL REMAIN WESTERLY. THEN
OVERNIGHT THE FRONTAL BOUNDARY WILL ARRIVE AND QUICKLY FLIP WINDS
TO NORTHWEST THEN NORTHEAST AROUND DAYBREAK TUESDAY. THIS WILL
USHER IN A STRATUS LAYER OF CLOUDS WITH BASES APPROACHING 1500FT
AGL AND PERHAPS A BRIEF PERIOD OF CIGS GOING BELOW 1KFT AGL AFT
DAYBREAK TUE.
BEACHLER
&&
.MARINE...
304 AM CDT
HEADLINES...REPLACED THE GALE WATCH WITH A GALE WARNING FOR LATE
THIS AFTERNOON INTO EARLY TUESDAY MORNING. ALSO ISSUED A SMALL
CRAFT ADVISORY FOR HAZARDOUS WAVES TUESDAY MORNING INTO WEDNESDAY
EVENING FOR THE IL NSH AND TUESDAY AFTN INTO WEDNESDAY AFTN FOR THE
INDIANA NSH WATERS.
A COLD FRONT IS OVER CENTRAL LAKE MICHIGAN WITH NE WINDS NORTH OF
THE FRONT AND SOUTHEAST WINDS TO THE SOUTH. WINDS WILL INCREASE TO
GALE FORCE OVER THE NORTHERN END LATE THIS AFTN WHILE WINDS ON THE
SOUTH HALF WILL BECOME SOUTHWEST THIS EVENING. THE FRONT WILL SHIFT
SOUTH AS THE WEAKENING LOW PASSES OVER THE SOUTHERN END OF THE LAKE
TONIGHT. WINDS BECOME NORTHEAST LEADING TO HAZARDOUS WAVES IN THE
NSH WATERS INTO WEDNESDAY EVENING. ANOTHER LOW MOVES OVER THE
PLAINS WEDNESDAY AND PASSES SOUTH OF THE LAKE THURSDAY. NORTHEAST TO
EAST WINDS TO 25 KT CONTINUE THROUGH THURSDAY AFTERNOON PROBABLY
LEADING TO ANOTHER PERIOD OF HAZARDOUS WAVES FOR AT LEAST THE IL NSH
WATERS. THE SOUTHERN END OF HIGH PRESSURE CENTERED OVER HUDSON BAY
ROTATES OVER THE LAKE LATE THIS WEEK WITH WEAK NORTH TO NORTHEAST
WINDS. ANOTHER LOW IS PROGGED TO SLOWLY SHIFT EAST FROM THE PLAINS
TO OVER CENTRAL IL AND INDIANA LAKE EARLY NEXT WEEK. THIS WILL
RESULT IN STRENGTHENING NORTHEAST WINDS.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...10 AM TUESDAY TO
10 PM WEDNESDAY.
SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...4 PM TUESDAY TO 4
PM WEDNESDAY.
&&
$$
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[top]
Area Forecast Discussion
National Weather Service Lincoln IL
243 PM CDT MON APR 25 2016
.SHORT TERM...(Tonight)
ISSUED AT 242 PM CDT Mon Apr 25 2016
Main concern in the short term remains with the severe weather
potential. CAPE values already in excess of 1000 J/kg across areas
northwest of the Illinois River, where the cumulus field has only
recently started to fill in. Best wind fields are further north
across Wisconsin and far northern Illinois, but some modest 0-6km
bulk shear values of around 30 knots were analyzed on the 18Z SPC
mesoscale analysis. Boundary located just ahead of the thinning band
of stratocumulus and seen as a fine line on the Davenport Doppler
radar just northwest of the Quad Cities as of 2 pm. This will likely
be the trigger for storm development over the next couple hours,
with latest HRRR model showing development by around 3 pm. Bulk of
that particular line progged to mainly be north of us with it
scraping the northern parts of the CWA through sunset, but with
further development a bit further south along the I-55 corridor
toward 6-7 pm. Severe threat will be on the wane by mid evening,
although a few stronger storms will still be possible over east
central Illinois.
With more of a multi-cell configuration this far south, have kept
PoP`s in the 30-40% range, with the threat shifting southward with
time. By about midnight, the northern CWA should be dry, with the
higher PoP`s continuing to spread into southeast Illinois.
&&
.LONG TERM...(Tuesday through Monday)
ISSUED AT 242 PM CDT Mon Apr 25 2016
Latest models have remained fairly consistent regarding their
guidance over the next several days, and forecast does not require
significant changes at this time. Forecast area will continue to be
impacted by predominantly southwest upper-level flow with systems
ejecting toward the region from the southwest U.S. every couple of
days. Downstream blocking pattern over eastern Canada & Greenland is
forecast to persist at least until the weekend which will tend to
deflect the disturbances on a more southerly track than their
original trajectory. This storm track will keep forecast area a
little cooler than was anticipated a few days ago (although still
near seasonal normals), and push the main severe weather threat
south of the area as well.
Tuesday should start out mostly dry across the forecast area, except
in the southeast where a front will still be hanging around. Then,
precipitation chances will ramp up, especially Tuesday night into
Wednesday, as vigorous wave (currently moving into Four Corners
region) approaches the Midwest. Thursday into Friday should be
mostly dry as we lie between systems. A final system, at least for
this forecast package, is expected to bring showers/storms to the
area for the weekend. This system is larger and slower moving than
the ones earlier in the week, and will likely result in a more
widespread/drawn out precipitation event.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1217 PM CDT Mon Apr 25 2016
Not a lot of change to the previous TAF set in regards to
scattered convection developing later today, but have made some
minor adjustments to the timing. Coverage is still uncertain
enough to go more than a VCTS mention, but will amend later once
it becomes more clear. Gusty south-southwest winds to around 25-30
knots this afternoon should subside toward 00Z. As a frontal
boundary settles southward late tonight, a trend toward the west
will occur, and areas near KPIA/KBMI likely to go more north or
northeast by late in the forecast period. With the frontal
boundary settling over the area, there are some indications of
potential MVFR ceilings after 12Z, especially north of this
boundary. Right now, will keep ceilings just above 3000 feet until
this becomes a bit more clear.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Geelhart
LONG TERM...BAK
AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
114 PM CDT MON APR 25 2016
.UPDATE...1029 AM CDT
TEMPERATURES ARE OFF TO THE RACES THIS MORNING...ALREADY CLIMBING
INTO THE LOWER 70S BY 10 AM ACROSS NORTHERN IL/NORTHWEST IN...AND
WILL CONTINUE TO RISE TOWARDS 80 BY EARLY THIS AFTERNOON. VISIBLE
IMAGERY INDICATES MOSTLY SUNNY SKIES OVERHEAD...WITH THE EXCEPTION
OF A CHANNEL OF STRATUS OVER EXTREME NORTHWEST ILLINOIS STRETCHING
SOUTHWEST THROUGH CENTRAL MISSOURI. THIS AREA OF LOWER CLOUDS WAS
SLOWLY LIFTING NORTHEAST...AND EXPECTED TO STEADILY THIN AS IT
ENCOUNTERS A WELL MIXED ENVIRONMENT OVER NORTHERN IL.
THEN THE FOCUS TURNS TOWARDS THIS AFTERNOON AND CONVECTIVE CHANCES
AS WELL AS TIMING. WHILE SFC INSTABILITY IS POISED TO
INCREASE...ESPECIALLY WITHIN THE 0-3KM LAYER...IT IS AN
APPROACHING 50KT MID-LVL WIND FIELD THAT IS CONCERNING AS IT
MERGES WITH A CONVERGENT AIRMASS OVER NORTHEAST ILLINOIS BETWEEN
21-23Z...ADDING TO THE SHEAR WITHIN THE MID LEVELS. ONCE
CONVECTION DEVELOPS...SOME STEADY/QUICK GROWTH INTO A FEW
SUPERCELLS WILL BE POSSIBLE BETWEEN 22-23Z THEN BEGIN TO SHIFT
EAST/SOUTHEAST ACROSS FAR NORTHEAST ILLINOIS TURNING INTO NORTHERN
INDIANA BY EARLY THIS EVENING. MAIN HAZARDS WILL BE ISOLATED
DAMAGING HAIL AND WIND THREATS.
ALL OF THE ACTIVITY SHOULD BE ON A DOWNWARD TREND BY 2-4Z AS A
FRONTAL BOUNDARY DIVES SOUTH ALONG THE LAKE AND DIFFLUENT FLOW
PUSHES IN FROM THE WEST/NORTHWEST AND FLOW TURNS NORTHERLY
OVERNIGHT.
BEACHLER
&&
.SHORT TERM...
344 AM CDT
THROUGH WEDNESDAY...
PRIMARY CONCERNS IN THE SHORT TERM INCLUDE THE UNSEASONABLY WARM
TEMPS TODAY...THUNDERSTORM CHANCES LATE THIS AFTERNOON AND
EVENING...THEN LAKE ENHANCED COLD FRONT AND FREE FALL IN TEMPS
EARLY TUESDAY.
CONVECTION OVER IOWA IS QUICKLY MEETING ITS DEMISE AS IT
ENCOUNTERS DRIER MORE STABLE AIR MASS. SHORTWAVE ASSOCIATED WITH
THAT CONVECTION WILL MOVE ACROSS OUR AREA LATER THIS MORNING...BUT
SUSPECT IT WILL PASS THROUGH WITHOUT MUCH FANFARE OTHER THAN
CLOUDINESS. A 997MB SFC LOW OVER SD WILL MOVE EAST INTO SOUTHERN
WISCONSIN BY THIS EVENING BUT STEADILY WEAKEN ALONG THE WAY AS
STRONG SHORTWAVE AND ASSOCIATED CLOSED LOW RAPIDLY WEAKENS AND
SHEARS EASTWARD INTO THE UPPER GREAT LAKES REGION TONIGHT. DESPITE
SOME CLOUDINESS...STILL LOOKING FOR UNSEASONABLY WARM TEMPS TODAY
LIKELY TOPPING OUT IN THE LOWER 80S...EVEN ALONG THE LAKEFRONT AS
MODERATELY BRISK SOUTHERLY WINDS BRING THE WARMTH RIGHT UP TO THE
SHORELINE.
CONVECTION IS REALLY THE TRICKIEST PART OF THE FORECAST IN THE
NEAR TERM. AFTER SHORTWAVE PASSES THIS MORNING REALLY HARD TO FIND
ANY FEATURE TO SUPPORT LARGE SCALE ASCENT...IN FACT...IF ANYTHING
LOOK FOR SOME VERY SUBTLE MID LEVEL HEIGHT RISES THIS
AFTERNOON/EVENING AS UPPER LOW QUICKLY FILLS. DESPITE THE LIMITED
TO NON-EXISTENT SUPPORT ALOFT...MAJORITY OF CONVECTIVE ALLOWING
MODELS (CAMS) BREAK OUT CONVECTION THIS AFTERNOON ALONG WEAK
ADVANCING COLD FRONT. SHOULD SEE MLCAPE VALUES APPROACHING 1000
J/KG IN ADVANCE OF THE FRONT AS DEWPOINTS POOL IN THE MID 50S TO
PERHAPS NEAR 60 ALONG THE FRONT AND SFC TEMPS WARM INTO THE LOW
80S. EVENING SOUNDINGS TO OUR WEST SHOW LARGE POOL OF STEEP MID
LEVEL LAPSE RATES WHICH AS FORECAST TO ADVECT EASTWARD INTO OUR
AREA THIS AFTERNOON WHICH SHOULD HELP WITH INSTABILITY...THOUGH IT
DOES LEAD TO QUESTIONS REGARDING WHETHER A WEAK CAPPING INVERSION
COULD DEVELOP AT BASE OF THIS ELEVATED MIXED LAYER.
CERTAINLY CONCERNS ARE THERE WITH SUCH WEAK FORCING AND POTENTIAL
CAPPING...BUT GIVEN THE UNANIMITY OF THE CAMS IN FIRING AT LEAST A
BROKEN LINE OF STORMS ALONG THE WEAK FRONT/PRE-FRONTAL TROUGH TO
OUR WEST THIS AFTERNOON...SPREADING EAST ACROSS OUR CWA VERY LATE
THIS AFTERNOON INTO EARLY THIS EVENING...FELT SOMEWHAT COMFORTABLE
HOLDING ONTO LOW END LIKELY POPS TONIGHT. ASSUMING STORMS DO
INDEED MATERIALIZE AS FORECAST...GUIDANCE SUGGESTS A 40-50KT 500MB
JET STREAK WILL MOVE INTO THE AREA THIS EVENING...WHICH SHOULD
RESULT IN SUFFICIENTLY STRONG SHEAR TO SUPPORT A THREAT OF LARGE
HAIL/DAMAGING WIND THREAT WITH ANY STORMS. BOTH SHEAR AND
INSTABILITY ARE FORECAST TO BE WITHIN THE RANGE TO SUPPORT
SUPERCELLS...WHICH WOULD ONLY ENHANCE THE HAIL THREAT. LARGE T/TD
SPREADS AND WEAKER LOW LEVEL SHEAR SHOULD LIMIT THE TORNADO
POTENTIAL.
STORMS SHOULD MOVE OUT OF THE AREA BETWEEN 06-09Z TUESDAY...THOUGH
IT WILL REMAIN MILD MUCH OF THE NIGHT TONIGHT. MODELS HAVE
CONTINUED TO TREND SLOWER WITH THE SECONDARY LAKE ENHANCED FRONT
WHICH IS POISED TO BRING A QUICK AND DRAMATIC END TO OUR SUMMER-
LIKE WARMTH. LATEST MODE RUNS NOW HAVE THE FRONT PLOWING IN OFF
THE LAKE EARLY TUESDAY MORNING WITH TEMPS DROPPING INTO THE 50S
BEHIND THE FRONT...EXCEPT INTO THE 40S NEAR THE LAKE. FRONT SHOULD
MOVE THROUGH SOUTHERN CWA DURING THE AFTERNOON ALLOWING FOR TEMPS
TO WARM INTO THE 70S AHEAD OF THE FRONT BEFORE TEMPS CRASH BEHIND
THE FRONT LATE.
IZZI
&&
.LONG TERM...
344 AM CDT
WEDNESDAY NIGHT THROUGH MONDAY...
ANOTHER STRONG NEGATIVELY TILTED SHORTWAVE WILL BRING SEVERE
WEATHER TO THE PLAINS TUESDAY AFTERNOON THEN BEGIN TO WEAKEN AS IT
MOVES TOWARD THE MIDWEST WEDNESDAY. NORTHEAST LOW LEVEL FLOW
SHOULD PROVIDE A STEADY FEED OF DRY AIR WHICH SHOULD HELP DELAY
THE ONSET OF THE PRECIP IN OUR CWA...ESPECIALLY THE FARTHER NORTH
AND EAST YOU GET. HAVE DELAYED THE ONSET OF THE HIGHER POPS FROM
PREVIOUS FORECAST. REALLY NOT LOOKING LIKE MUCH OF A THUNDERSTORM
THREAT THIS FAR NORTH AS WEAK LAPSE AND QUICKLY WEAKENING SYSTEM
KEEPS LOW LEVEL JET AND POTENTIAL FOR LLJ DRIVEN STORMS FAIRLY
LOW. STILL LOOKS LIKE A DECENT RAIN EVENT WEDNESDAY INTO WEDNESDAY
NIGHT. DRIER AND SEASONABLY CHILLY CONDITIONS ARE EXPECTED IN THE
WAKE OF THIS SYSTEM LATER THURSDAY INTO FRIDAY BEFORE WE RINSE AND
REPEAT WITH ANOTHER STRONG NEGATIVELY TILTED CLOSED LOW MOVING
INTO THE PLAINS BEFORE SLOWLY WEAKENING AS IT WOBBLES INTO OUR
AREA NEXT WEEKEND WITH RAIN CHANCES RETURNING. ONCE FRONT MOVES
THROUGH TOMORROW MORNING LOOK FOR CHILLY WINDS OFF THE LAKE TO
LOCK IN FOR THE REST OF THE WEEK AND PROBABLY INTO THE WEEKEND AS
WELL.
IZZI
&&
.AVIATION...
FOR THE 18Z TAFS...
VFR CONDS CONTINUE ACROSS NORTHERN IL/NORTHWEST IN
AIRFIELDS...HOWEVER THE FOCUS REMAINS ON POTENTIAL FOR CONVECTION
TO DEVELOP LATER THIS AFTERNOON THROUGH EARLY EVENING. WINDS WILL
REMAIN BREEZY FROM THE SOUTH TURNING SOUTHWEST AHEAD OF THE
CONVECTION...WITH SPEEDS GENERALLY AROUND 10 TO 15 KT AND GUSTS
BETWEEN 20 TO 25 KT AT TIMES. VISIBLE IMAGERY DOES SHOW A LAYER OF
CUMULUS CLOUDS DEVLEOPING WITH BASES AROUND 5-6KFT AGL...HOWEVER
AS OF MIDDAY THE VERTICAL GROWTH TO THE CUMULUS LAYER DOES NOT
LOOK TOO IMPRESSIVE...WHICH COULD DELAY THE TIMING FOR
SHOWERS/THUNDERSTORMS SLIGHTLY. GUIDANCE CONTINUES TO POINT
TOWARDS 22Z FOR DEVELOPMENT OF SHOWERS/THUNDERSTORMS WESTERN
IL...THEN QUICKLY INCREASEING IN INTENSITY BY 23Z AND APPROACHING
THE CHICAGO METRO TAF SITES. THE CONVECTION SHOULD BE PROGRESSIVE
AND PUSH EAST OF THE ORD/MDW SITES BY 00Z TO PERHAPS JUST AFTER
00Z...WITH CONVECTION ENDING BY 1Z TUE. THE FRONTAL BOUNDARY
REMAINS WELL NORTH/WEST OF THE AIRFIELDS...SO EXPECT ONCE
CONVECTION PUSHES THROUGH THAT WINDS WILL REMAIN WESTERLY. THEN
OVERNIGHT THE FRONTAL BOUNDARY WILL ARRIVE AND QUICKLY FLIP WINDS
TO NORTHWEST THEN NORTHEAST AROUND DAYBREAK TUESDAY. THIS WILL
USHER IN A STRATUS LAYER OF CLOUDS WITH BASES APPROACHING 1500FT
AGL AND PERHAPS A BRIEF PERIOD OF CIGS GOING BELOW 1KFT AGL AFT
DAYBREAK TUE.
BEACHLER
&&
.MARINE...
304 AM CDT
HEADLINES...REPLACED THE GALE WATCH WITH A GALE WARNING FOR LATE
THIS AFTERNOON INTO EARLY TUESDAY MORNING. ALSO ISSUED A SMALL
CRAFT ADVISORY FOR HAZARDOUS WAVES TUESDAY MORNING INTO WEDNESDAY
EVENING FOR THE IL NSH AND TUESDAY AFTN INTO WEDNESDAY AFTN FOR THE
INDIANA NSH WATERS.
A COLD FRONT IS OVER CENTRAL LAKE MICHIGAN WITH NE WINDS NORTH OF
THE FRONT AND SOUTHEAST WINDS TO THE SOUTH. WINDS WILL INCREASE TO
GALE FORCE OVER THE NORTHERN END LATE THIS AFTN WHILE WINDS ON THE
SOUTH HALF WILL BECOME SOUTHWEST THIS EVENING. THE FRONT WILL SHIFT
SOUTH AS THE WEAKENING LOW PASSES OVER THE SOUTHERN END OF THE LAKE
TONIGHT. WINDS BECOME NORTHEAST LEADING TO HAZARDOUS WAVES IN THE
NSH WATERS INTO WEDNESDAY EVENING. ANOTHER LOW MOVES OVER THE
PLAINS WEDNESDAY AND PASSES SOUTH OF THE LAKE THURSDAY. NORTHEAST TO
EAST WINDS TO 25 KT CONTINUE THROUGH THURSDAY AFTERNOON PROBABLY
LEADING TO ANOTHER PERIOD OF HAZARDOUS WAVES FOR AT LEAST THE IL NSH
WATERS. THE SOUTHERN END OF HIGH PRESSURE CENTERED OVER HUDSON BAY
ROTATES OVER THE LAKE LATE THIS WEEK WITH WEAK NORTH TO NORTHEAST
WINDS. ANOTHER LOW IS PROGGED TO SLOWLY SHIFT EAST FROM THE PLAINS
TO OVER CENTRAL IL AND INDIANA LAKE EARLY NEXT WEEK. THIS WILL
RESULT IN STRENGTHENING NORTHEAST WINDS.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...10 AM TUESDAY TO
10 PM WEDNESDAY.
SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...4 PM TUESDAY TO 4
PM WEDNESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1217 PM CDT MON APR 25 2016
.UPDATE...
Issued at 1014 AM CDT Mon Apr 25 2016
Early morning scattered clouds have been thinning out and moving
east out of the area, with mostly sunny conditions at midday. Wind
gusts starting to reach the 25-30 mph range in several areas as
the low level inversion seen on the morning sounding mixes out.
Temperatures have already reached the 70-75 degree range across
the CWA. While clouds should start to increase later today,
CAPE`s expected to reach over 1500 J/kg by mid afternoon over west
central Illinois, helping to fuel some scattered thunderstorms.
Have done some tweaking to the timing of the convection, starting
the PoP`s northwest of the Illinois River around 2-3 pm and
bringing them about as far as Springfield-Rantoul by late
afternoon. Latest HRRR and the evening run of the NSSL 1km ARW do
suggest some scattered convection more in the Decatur-Champaign
area late afternoon, so have maintained the slight chance PoP`s in
that area but limited them to late afternoon. Greatest convection
still expected more across northern Illinois, shifting southward
as the boundary moves into central Illinois/Indiana tonight.
Northern parts of the CWA should pretty much be dry by midnight,
and have removed the post-midnight PoP`s in that area.
&&
.SHORT TERM...(Today)
ISSUED AT 333 AM CDT Mon Apr 25 2016
Storm system over eastern South Dakota as of 300 am is expected to
track east along a stalled frontal boundary over northern Iowa east
through southern Wisconsin later today. A cold front located from
the low over eastern South Dakota southward through eastern Nebraska
will track slowly east today and not get into our area until first
thing Tuesday morning. Surface dew points in the mid to upper 50s
were noted just east of the cold front and as the boundary shifts
east today, so will the moist axis into our area this afternoon.
As was advertised with most model data, the storms that occurred
last night in Iowa have dissipated with the latest surface analysis
indicating a weak boundary/remnant outflow boundary over east
central Iowa. Most of the high res reflectivity simulations off the
4km NAM along with the WRF-ARW and NMM indicate redevelopment in
west-central Illinois later this afternoon. Surface temperatures in
the lower 80s combined with dew points in the upper 50s will yield
ML capes of around 1800 in a few areas along and west of the
Illinois River later this afternoon. That combined with rather steep
mid level lapse rates and 0-6km shear values of around 40 kts will
bring the threat for scattered thunderstorms after 300 pm, some of
which may produce strong winds and large hail, roughly along and
west of a Springfield to Bloomington line.
.LONG TERM...(Tonight through Sunday)
ISSUED AT 333 AM CDT Mon Apr 25 2016
After another warm day, with showers and thunderstorms chances
through the afternoon and into the evening hours, a series of
weather systems will bring precip for most of this week. The first
wave has slowed on approach overall, delaying the onset of precip.
Also, models are having some consistency issues with the extent of
the southerly progression of the front before the next wave moves
into the Midwest and enhances the precip/storms for Tuesday night
and into Wednesday. Much of ILX sits in an area with limited severe
weather potential partially due to timing of the system late Tuesday
in the overnight hours. At any rate, the deep low over the southern
Plains ejects out and into the region, spreading best chances for
precipitation Wednesday and Wednesday night. Models still limiting
the progression of the warm front, keeping temperatures not quite as
warm for Tue/Wed ahead of the advancing storm center. By late
Thursday, the winds become more northerly and drier air slowly tries
to build back in for a brief break Thu night through later Friday.
The break looks to be short lived again as another wave moves out of
the long wave trof over the SW and into the region, bringing precip
back for next weekend. Overall, an active pattern, with more wet
than dry.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1217 PM CDT Mon Apr 25 2016
Not a lot of change to the previous TAF set in regards to
scattered convection developing later today, but have made some
minor adjustments to the timing. Coverage is still uncertain
enough to go more than a VCTS mention, but will amend later once
it becomes more clear. Gusty south-southwest winds to around 25-30
knots this afternoon should subside toward 00Z. As a frontal
boundary settles southward late tonight, a trend toward the west
will occur, and areas near KPIA/KBMI likely to go more north or
northeast by late in the forecast period. With the frontal
boundary settling over the area, there are some indications of
potential MVFR ceilings after 12Z, especially north of this
boundary. Right now, will keep ceilings just above 3000 feet until
this becomes a bit more clear.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...Smith
LONG TERM...HJS
AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
600 PM EDT MON APR 25 2016
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 218 PM EDT MON APR 25 2016
LOW PRESSURE OVER MINNESOTA IS EXPECTED TO PUSH EAST THROUGH THE
GREAT LAKES TONIGHT. AS THE LOW PASSES...A COLD FRONT WILL SAG
SOUTH ACROSS INDIANA ON LATE TONIGHT AND TUESDAY.
THE FRONTAL BOUNDARY IS EXPECTED TO LINGER ACROSS CENTRAL INDIANA
THROUGH THURSDAY. THIS WILL RESULT IN CHANCES FOR RAIN FOR MUCH
OF THE MIDDLE OF THE WORK WEEK AND INTO THE WEEKEND...ALONG WITH
SEASONABLE TEMPERATURES.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 218 PM EDT MON APR 25 2016
SURFACE ANALYSIS EARLY THIS AFTERNOON SHOWS LOW PRESSURE OVER
MINNESOTA. A WARM FRONT EXTENDED EAST FROM THE LOW ACROSS
SOUTHERN WISCONSIN AND SOUTHERN MICHIGAN. WARM SOUTHERLY FLOW WAS
IN PLACE ACROSS INDIANA AND THE OHIO VALLEY.
MAIN FORECAST CHALLENGE TONIGHT WILL BE POPS.
GFS AND NAM SUGGEST THE LOW WILL PUSH EAST ALONG THE
FRONT...STAYING WELL NORTH OF INDIANA. HOWEVER AS THE LOW PASSES
THE FRONT WILL BEGIN TO PUSH SOUTHWARD AS A COLD FRONT...REACHING
NORTHERN INDIANA BY TUESDAY MORNING. TIME HEIGHTS ACROSS THE AREA
FAIL TO SHOW ANY DEEP MOISTURE ARRIVING...AND FORECAST SOUNDINGS
ALSO SHOW AN EXTENSIVE DRY LAYER WITHIN THE COLUMN. FARTHER
ALOFT...MINIMAL UPPER SUPPORT APPEARS AVAILABLE AS BEST DYNAMICS
REMAIN ACROSS THE GREAT LAKES. EVEN A OVERRUNNING SITUATION
OVERNIGHT LOOKS WEAK...AS 850 WIND FIELD SUGGESTS ONLY AROUND 30
KNOTS OF SOUTHWEST WIND PUSHING INTO THE FRONT. THUS CONFIDENCE
FOR POPS TONIGHT IS LOW. WILL KEEP A LOW CHC POP...MAINLY LATE
ACROSS THE NRN PARTS OF THE FORECAST AREA...BUT WILL TRY TO TREND
TOWARD A DRY FORECAST PERIOD ELSEWHERE...COLLABORATION WILLING.
AS FOR TEMPS...WEAK WARM AIR ADVECTION CONTINUES THROUGH THE NIGHT
AND THE COLD FRONT FAILS TO ARRIVE BY 12Z...STILL LINGERING WELL
NORTH OF THE FORECAST AREA. THUS WITH CLOUD COVER AND WARM AIR
ADVECTION EXPECTED...WILL TREND LOWS WARMER THAN GUIDANCE.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
ISSUED AT 218 PM EDT MON APR 25 2016
ACTIVE WEATHER PATTERN POISED TO SET THROUGH THE MIDDLE OF THE
WEEK.
MODELS SUGGEST THAT A SURFACE FRONTAL BOUNDARY LOOKS TO BE
SETTLING ACROSS CENTRAL INDIANA ON TUESDAY MORNING.
MEANWHILE...MODELS ARE SUGGESTING A RIDGING RIDING SHORTWAVE TO
ARRIVE ALOFT DURING THE AFTERNOON HOURS. FORECAST SOUNDINGS SHOW
DEEP MOISTURE AVAILABLE DURING THE AFTERNOON HOURS...WITH BEST
FORCING FOUND MAINLY SOUTH OF INTERSTATE 70. FORECAST SOUNDINGS
SHOW REACHABLE CONVECTIVE TEMPS IN THE LOWER 70S...AND OVER 2K
J/KG OF CAPE AVAILABLE. PWATS ARE OVER AN INCH. THUS WILL TREND
POPS HIGH ON TUESDAY...PARTICULARLY ACROSS THE SOUTHERN PARTS OF
THE FORECAST AREA WHERE FORCING IS BEST. GIVEN THE MIX OF SUN IN
THE MORNING AND PRECIP CHANCES THROUGH THE AFTERNOON...WILL TREND
TEMPS CLOSE TO MAVMOS.
A LULL IN PRECIP CHANCES IS THEN EXPECTED ON TUESDAY NIGHT AS THE FORCING
ALOFT DEPARTS TO THE SOUTHEAST AND HEATING IS LOST. GFS AND NAM
SUGGEST RIDGING BUILDING ALOFT THROUGH WEDNESDAY MORNING AS THE
SURFACE BOUNDARY CONTINUES TO LINGER ACROSS THE STATE. WITH
FORCING LOST TUESDAY NIGHT...WILL TREND TOWARD A DRY FORECAST
THROUGH WEDNESDAY MORNING. AS FOR TEMPS DURING THIS TIME WITH
EXPECTED CLOUDS LINGER WILL TREND WARMER THAN MAVMOS.
ON WEDNESDAY AFTERNOON THROUGH THURSDAY AFTERNOON...THE GFS AND
NAM SUGGEST A DEEPER LOW WITHIN THE LOW ALOFT OVER NEBRASKA. A
NEGATIVELY TILED SHORT WAVE PIVOTING AROUND THAT SYSTEM LOOKS TO
PUSH ACROSS INDIANA DURING THE AFTERNOON AND OVERNIGHT HOURS ON
WEDNESDAY AND WEDNESDAY NIGHT. GFS 305K ISENTROPIC SURFACE SHOWS
EXCELLENT ISENTROPIC LIFT AT THAT TIME WITH SPECIFIC HUMIDITIES
OVER 4.5 G/KG. FURTHERMORE...FORECAST SOUNDINGS INDICATING DEEP
SATURATION. THUS WILL TREND POPS ON WEDNESDAY AFTERNOON THROUGH
THURSDAY HIGHER THAN GUIDANCE...KEEPING LOWS WARMER THAN MAVMOS
AND HIGHS COOLER.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
ISSUED AT 238 PM EDT MON APR 25 2016
MODEL ENSEMBLES INDICATE HIGH PRESSURE WILL REMAIN OVER NORTHERN
MANITOBA AND THE HUDSON BAY WHILE A FRONTAL SYSTEM REMAINS
ACROSS TENNESSEE TO THE SOUTHERN PLAINS. A COUPLE AREAS OF
LOW PRESSURE WILL MOVE EAST ALONG THIS FRONTAL SYSTEM.
ONE WILL BE MOVING EAST OUT OF THE OHIO VALLEY THURSDAY EVENING
AND ANY LINGERING SHOWERS SHOULD END BY MIDNIGHT.
FRIDAY WILL BE DRY. THEN OVER THE WEEKEND...THERE WILL BE INCREASING
CHANCES OF SHOWERS OVER THE WEEKEND AS LOW PRESSURE MOVES FROM OKLAHOMA
SATURDAY TO SOUTHEAST MISSOURI AND WESTERN KENTUCKY SUNDAY AND SOUTHERN
OHIO TUESDAY. THE 12Z GFS AND GEMNH MODELS KEEP US DRY UNTIL SATURDAY
EVENING...WHILE THE EURO BEGINS RAIN CHANCES 6 TO 12 HOURS SOONER.
WILL TWEAK THE BLENDED POPS DOWN SLIGHTLY SATURDAY...OTHERWISE MADE NO
SIGNIFICANT CHANGES TO OTHER PERIODS.
STAYED CLOSE TO A MODEL BLEND ON TEMPERATURES WITH HIGHS IN THE 60S
NORTH AND CENTRAL TO NEAR 70 SOUTH AND LOWS FROM 45 TO 50 NORTH AND
50S SOUTH.
&&
.AVIATION /DISCUSSION FOR 260000Z TAF ISSUANCE/...
ISSUED AT 600 PM EDT MON APR 25 2016
MODERATE CONFIDENCE THAT VFR CONDITIONS WILL DETERIORATE TO MVFR IN
THE 08Z-14Z TIME FRAME. WOULD ALSO NOT RULE OUT A THUNDERSTORM
OVERNIGHT...BUT NOT ENOUGH CONFIDENCE THERE WILL BE ENOUGH COVERAGE
TO PUT IN THE TAFS AS HRRR REFLECTIVITY PROGS ARE ALREADY OVERDOING
THINGS BASED ON RADAR. WILL THROW SOME VCTS IN TUESDAY AFTERNOON AS
COVERAGE SHOULD INCREASE SOUTH OF LAF AS A FRONTAL BOUNDARY DROPS
DOWN FROM THE NORTH.
WINDS WILL BE SOUTHWEST 10 KNOTS OR SO TONIGHT AND WEST AND
NORTHWEST LESS THAN 10 KNOTS IN THE WAKE OF THE FRONT TUESDAY.
CONFIDENCE IN FRONTAL TIMING IS NOT GREAT...BUT HAVE IT THROUGH LAF
AT 14Z AND IND AND HUF AT 18Z. DO NOT THINK IT WILL REACH BMG BY 00Z
WEDNESDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...PUMA
NEAR TERM...PUMA
SHORT TERM...PUMA
LONG TERM....JH
AVIATION...MK
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
328 PM EDT MON APR 25 2016
.SYNOPSIS...
ISSUED AT 319 PM EDT MON APR 25 2016
INCREASING SOUTHWESTERLY WINDS WILL HELP DRAW IN WARMER AND
INCREASINGLY HUMID AIR TO HELP SET THE STAGE FOR SHOWERS AND
THUNDERSTORMS...MAINLY DURING THE EVENING HOURS. SOME OF THE STORMS
MAY BE STRONG TO POSSIBLY SEVERE. LOWS TONIGHT WILL RANGE FORM THE
LOWER 50S NEAR LAKE MICHIGAN TO THE MIDDLE AND UPPER 50S
ELSEWHERE. TEMPERATURES WILL RISE LITTLE ALONG THE LAKESHORE AREAS
ON TUESDAY BUT SHOULD REACH WELL INTO THE 60S TO LOWER 70S FOR THE
REMAINDER OF THE AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 319 PM EDT MON APR 25 2016
FOCUS OF SHORT TERM WILL BE ON CONVECTIVE POTENTIAL INTO THE
OVERNIGHT HOURS.
PARTLY TO MOSTLY SUNNY SKIES AND INCREASING SOUTHERLY WINDS HAVE
ALLOWED TEMPERATURES TO CLIMB WELL INTO THE 70S AND PUSH 80 IN SOME
LOCATIONS. DEWPOINTS ARE STEADILY INCREASING AS WELL...NOW INTO THE
MIDDLE 50S WITH 58 TO 62 DEGREE DEWPOINTS OFF TO THE WEST. LOW
PRESSURE WAS CENTERED OVER SE MINNESOTA WITH A WARM FRONT INTO
SOUTHERN LOWER MICHIGAN AND COLD FRONT BACK IN EASTERN IOWA.
CONVECTIVE INITIATION EXPECTED TO COMMENCE IN THE NEXT COUPLE OF
HOURS ACROSS NORTHERN ILLINOIS/SOUTHERN WISCONSIN AND MOVE EAST AND
SOUTH INTO THIS EVENING. EXACTLY HOW THE CONVECTION EVOLVES FROM
THERE REMAINS A CHALLENGE AS HI RES MODELS SHOW DIFFERENCES IN TIMING
AND INTENSITY. LAST SEVERAL RUNS OF HRRR HAVE BEEN MOST AGGRESSIVE AND
FASTEST WITH INITIAL CELLS CONGEALING INTO LINE OF STORMS...POSSIBLY
SEVERE WHICH ARRIVES AROUND OR SHORTLY AFTER 00Z AND PROGRESSES
THROUGH THE AREA. RAP/NMM MORE FOCUS ON THE WARM FRONT AND KEEP
ACTIVITY MORE SCATTERED AND FURTHER NORTH. NAM/NAM 4KM SHOW SOME
SIMILARITY TO HRRR BUT SLOWER AND LESS ROBUST. GRIDS WERE UPDATED TO
LIMIT PRECIP POTENTIAL UNTIL AFTER 21Z WITH LITTLE IN THE WAY OF
FORCING MECHANISMS AROUND TO HELP USE THE LIMITED INSTABILITY. SHEAR
PROFILES DO INCREASE THIS EVENING...BUT INSTABILITY WILL BE ON THE
DECREASE. MID LEVEL JET WILL BE IMPINGING ON THE CONVECTION WITH
SOME HINTS OF A SMALL EML THROUGH EARLY EVENING BEFORE BEING LOST.
HAVE REMOVED THE SMALL AREA OF CATEGORICAL POPS AND WENT WITH SOME
ATTEMPT TO TIME OUT ANY CONVECTION WITH HIGH CHC TO LIKELY POPS.
PRECIP MAY LINGER LONGEST IN THE SE BUT WILL LIKELY BE WEAKENING BY
THIS POINT. TRIED TO LIMIT SOUTHERN EXTENT OF THE CONVECTION WITH
LOCATIONS SOUTH OF US-24 POSSIBLY NOT SEEING MUCH.
FRONTAL BOUNDARY WILL LINGER TO THE SOUTH OF THE AREA WITH POTENTIAL
FOR A FEW SHOWERS AND STORMS IN FAR S/SE AREAS INTO TUESDAY
AFTERNOON. SHOULDN`T BE ANYTHING TO WORRY ABOUT WITH GREATER SEVERE
THREAT SOUTH AND ESPECIALLY WELL SOUTHWEST OF THE AREA. COOL DAY IN
STORE ALONG THE LAKE WITH HIGHS IN THE MIDDLE 50S VS MIDDLE 60S TO
MIDDLE 70S INLAND.
&&
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 319 PM EDT MON APR 25 2016
TWO PRIMARY CHANCES OF RAIN DURING THIS LONG TERM PERIOD AS PAIR OF
DEEP WESTERN CONUS TROUGHS EJECT EASTWARD. THE FIRST IS CURRENTLY
CLOSING OFF OVER NEVADA. AS THIS PV ANOMALY MOVES INTO OUR REGION ON
WED...TIGHTENING BAROCLINIC ZONE/FGEN WILL SET UP OVER THE SOUTHERN
GREAT LAKES. GOOD CROSS-ISOBAR FLOW AND MOISTURE ADVECTION ON THE
300K SURFACE WITH MIXING RATIOS AROUND 8 G/KG. PW VALUES ALSO CLIMB
TO AROUND 1.2 INCHES BY LATE WEDNESDAY. THETA-E SURGE IN PRESENCE OF
GOOD ISENTROPIC ASCENT AND INCREASING CVA WILL LIKELY LEAD TO NUM
SHOWERS LATE WED INTO THURS. ADDED A BIT MORE TEMPORAL DETAIL TO POP
FORECAST...SLOWING DOWN ARRIVAL AND INCREASING TO CATEGORICAL WED
NIGHT BASED ON GOOD AGREEMENT IN 12Z MODEL SUITE. DID KEEP IN A
SLIGHT CHANCE OF THUNDER BUT PLACEMENT OF FRONTAL BOUNDARY WILL KEEP
SURFACE-BASED INSTABILITY LOCKED TO OUR SOUTH AND ELEVATED
INSTABILITY LOOKS PRETTY MEAGER BASED ON FORECAST SOUNDINGS.
MIDLEVEL VORT LOBE WILL EXIT EARLY FRIDAY MORNING WITH DRY
CONDITIONS FRI INTO EARLY SAT.
ROUND TWO (POTENTIALLY) ARRIVES IN SIMILAR FASHION LATE SAT INTO
SUNDAY...AND POSSIBLY MONDAY. MODEL AGREEMENT REMAINS POOR THOUGH
WITH LATEST GFS KEEPING SURFACE LOW AND ALL PRECIP WELL SOUTH OF OUR
AREA. CONTINUED WITH CONSENSUS CHANCE POPS FOR NOW GIVEN IT IS AT
THE VERY END OF THIS FORECAST PERIOD. TEMPS THROUGH THIS WEEK WILL
BE SLIGHTLY BELOW AVERAGE FOR THIS TIME OF YEAR...THOUGH NOT
PARTICULARLY COLD AND FROST POTENTIAL APPEARS LOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1216 PM EDT MON APR 25 2016
WINDS HAVE BEEN STRUGGLING TO PICK UP AS PATCHES OF CLOUDS MOVE
THROUGH. SHOULD SEE BETTER MIXING TAKE PLACE THIS AFTERNOON AS
SOME CLEARING TAKES PLACE.
ATTENTION WILL THEN SHIFT TO EXPECTED UPSTREAM DEVELOPMENT OF AT
LEAST SCATTERED SHOWER/STORM ACTIVITY WHICH WILL MOVE EAST AND
LIKELY EXPAND/INTENSIFY AS IT APPROACHES THE AREA. MODELS VARYING
ON TIMING WITH ONE MODELS BRINGING STORMS INTO KSBN AS EARLY AS 1Z
WHILE OTHERS HOLD CLOSER TO 3-4Z WINDOW. MAY ADJUST TIMING BY AN
HOUR OR SO...BUT UNTIL DEVELOPMENT OCCURS DON`T WANT TO MAKE TOO
MANY CHANGES WITH AMENDMENT ISSUED ONCE PICTURE IS CLEARER. ONCE
THE COLD FRONT MOVES THROUGH...RAPIDLY IMPROVING CONDITIONS SHOULD
DOMINATE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...JT/SKIPPER
SHORT TERM...FISHER
LONG TERM...AGD
AVIATION...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
NWS NORTHERN INDIANA
1256 PM EDT MON APR 25 2016
.SYNOPSIS...
ISSUED AT 1217 PM EDT MON APR 25 2016
INCREASING SOUTHWESTERLY WINDS WILL HELP DRAW IN WARMER AND
INCREASINGLY HUMID AIR TO HELP SET THE STAGE FOR SHOWERS AND
THUNDERSTORMS...MAINLY DURING THE EVENING HOURS. WARMER AIR WILL
SPREAD NORTHEAST INTO OUR AREA AHEAD OF A COLD FRONT. HIGHS SHOULD
REACH THE UPPER 70S TO AROUND 80. A COLD FRONT WILL MOVE INTO OUR
AREA TONIGHT WITH A GOOD CHANCE FOR SHOWERS AND THUNDERSTORMS.
SOME STORMS MAY BE STRONG TO POSSIBLY SEVERE. LOWS TONIGHT WILL
RANGE FROM 55 TO 60.
&&
.UPDATE...
ISSUED AT 1216 PM EDT MON APR 25 2016
DIFFICULT FORECAST FOR THE NEXT 6 TO 12 HOURS AS MODELS CONTINUE
TO STRUGGLE WITH POTENTIAL EVOLUTION OF CONVECTION BOTH UPSTREAM
AND OVER THE FORECAST AREA AHEAD OF A APPROACHING COLD FRONT.
HRRR HAS BECOME MORE AGRESSIVE WITH DEVELOPMENT OF SCATTERED CONVECTION
BACK ACROSS ILLINOIS IN THE 20 TO 22Z WINDOW MOVING RAPIDLY EAST
AND EXPANDING/ELONGATING INTO A LINE OF STRONG (SEVERE?) STORMS
THAT APPROACH FAR W/NW AREAS AS EARLY AS 00Z. IF THIS WERE TO COME
TO FRUITION...A MORE FAVORABLE SETUP FOR ISOLATED TO MAYBE SCT
SEVERE STORMS WOULD OCCUR AS SOMEWHAT BETTER INSTABILITY WILL BE
IN PLACE. NAM 4KM GIVES A SIMILAR SCENERIO IN TERMS OF STG/LOCALLY
SEVERE STORMS BUT STICKS CLOSER TO THE 3-4Z ARRIVAL WINDOW IN THE
FAR NW. RAP SORT OF IN BETWEEN BUT RATHER NON DESCRIPT IN
HANDLING. TO COMPLICATE THINGS FURTHER...15Z HRRR SHOWS WIDELY
SCATTERED SHOWERS/STORMS DEVELOPING IN THE 18 TO 20Z TIME FRAME
WELL AHEAD OF EVERYTHING. LOOKING OUTSIDE...CU ALREADY STARTING TO
FORM SUGGESTING MID LEVEL INSTABILITY MAY BE INCREASING AND COULD
BE SUFFICENT TO SPARK OFF SOME CONVECTION. SPC MESO ALSO SHOWING A
FEW HUNDRED J/KG OF MLCAPE ACROSS THE AREA. TO ADD TO THE
MIX...SPC HAS EXPANDED THE SLGT RISK EASTWARD FROM ROUGHLY
NORTHWEST OF A MONTICELLO TO WARSAW TO WAUSEON OHIO LINE. CHANGES
IN POPS/WX WILL BE NEEDED OVER THE NEXT COUPLE OF HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 408 AM EDT MON APR 25 2016
A SURFACE LOW WILL TRACK EAST INTO THE UPPER MIDWEST TODAY. DEEP
MIXING WITH A TIGHTENING SURFACE PRESSURE GRADIENT ASSOCIATED WITH
THIS SYSTEM WILL CAUSE WINDY CONDITIONS OVER THE FORECAST AREA.
RAISED WIND SPEEDS A LITTLE IN LINE WITH THE LATEST MODEL GUIDANCE.
FAVORED THE GFS TREND THE PAST SEVERAL RUNS TOWARD A SLOWER AND MORE
NORTHWEST LOW TRACK SOLUTION. NOT MUCH FORCING FOR STORMS TODAY...
BUT INCREASING MOISTURE WITH DAYTIME HEATING MAY BE SUFFICIENT TO
SUPPORT SOME SHOWERS OVER LOWER MICHIGAN INTO FAR NORTHERN INDIANA.
THERE IS A MUCH BETTER CHANCE FOR SHOWERS AND STORMS TONIGHT AS
LOW LEVEL MOISTURE SURGES NORTHEAST AHEAD OF A COLD FRONT. THE
STORM PREDICTION CENTER INDICATED SOME STORMS MAY BE MARGINALLY
SEVERE OVERNIGHT. AN ELEVATED MIXED LAYER WILL BE IN PLACE
OVERNIGHT AS A FRONT APPROACHES. SURFACE BASED NAM CAPES SHOULD
RISE ABOVE 500 J/KG AS FAVORABLE 0-3KM SHEAR RISES TO 40 M/S. SO
BEST CHANCE FOR STORMS APPEARS TO BE FROM LATE EVENING UNTIL ABOUT
4 AM EDT WITH SOME STORMS STRONG TO POSSIBLY SEVERE DURING THIS
PERIOD.
&&
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 408 AM EDT MON APR 25 2016
SEVERAL SHORT WAVES EXPECTED TO IMPACT THE REGION DURING THIS LONG
TERM PERIOD. CONFIDENCE IN DETAILS LOW GIVEN MODEL PERFORMANCE AND
WAVERING WITH THIS FIRST SHORT WAVE TO START THE WEEK. BEST CHANCES
FOR PCPN LOOKS TO BE WEDNESDAY WITH ANOTHER STRONG SHORT WAVE AND
SFC LOW MOVING SOUTH OF THE AREA. STILL MODEL DISCREPANCIES WITH
STRENGTH AND TRACK OF THIS FEATURE. DID ALLOW LIKELY POPS TO
CONTINUE BUT NOT CONFIDENT ENOUGH IN CATEGORICAL YET. BASICALLY
FOLLOWED SUPERBLEND IN DAYS 4-7 WITH SLIGHT LOWERING OF POPS FROM
LIKELY TO CHANCE GIVEN UNCERTAINTY WITH CONVECTION AND STACKED
SYSTEM IN PLAINS LATE WEEK LIKELY COMING OUT SLOWER THAN MODEL
FORECAST. TEMPS WILL TREND COOLER WED AND THU WITH EASTERLY FLOW AND
PCPN CHANCES. TEMPS WILL TREND BACK TO NEAR NORMAL LATE WEEK INTO
THE WEEKEND AHEAD OF NEXT WAVE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1216 PM EDT MON APR 25 2016
WINDS HAVE BEEN STRUGGLING TO PICK UP AS PATCHES OF CLOUDS MOVE
THROUGH. SHOULD SEE BETTER MIXING TAKE PLACE THIS AFTERNOON AS
SOME CLEARING TAKES PLACE.
ATTENTION WILL THEN SHIFT TO EXPECTED UPSTREAM DEVELOPMENT OF AT
LEAST SCATTERED SHOWER/STORM ACTIVITY WHICH WILL MOVE EAST AND
LIKELY EXPAND/INTENSIFY AS IT APPROACHES THE AREA. MODELS VARYING
ON TIMING WITH ONE MODELS BRINGING STORMS INTO KSBN AS EARLY AS 1Z
WHILE OTHERS HOLD CLOSER TO 3-4Z WINDOW. MAY ADJUST TIMING BY AN
HOUR OR SO...BUT UNTIL DEVELOPMENT OCCURS DON`T WANT TO MAKE TOO
MANY CHANGES WITH AMENDMENT ISSUED ONCE PICTURE IS CLEARER. ONCE
THE COLD FRONT MOVES THROUGH...RAPIDLY IMPROVING CONDITIONS SHOULD
DOMINATE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
UPDATE...FISHER
SYNOPSIS...JT/SKIPPER
SHORT TERM...SKIPPER
LONG TERM...LASHLEY
AVIATION...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...UPDATED
NWS QUAD CITIES IA IL
1219 PM CDT MON APR 25 2016
...AVIATION UPDATE...
.UPDATE...
ISSUED AT 1029 AM CDT MON APR 25 2016
STILL ON TRACK FOR STRONG TO SEVERE STORMS THIS AFTERNOON AS H5
AND H3 JET APPROACHES THE AREA. THIS WITH A SURGE IN THE SFC
BOUNDARY WILL LEAD TO CONVERGENCE AT THE SFC AND STORM INITIATION
AROUND 19Z. BEST CHANCES FOR SEVERE WEATHER WILL BE IN OUR
ILLINOIS ZONES AS STORMS MATURE. DEEP LAYER SHEAR AND HIRES MODELS
SUGGEST ISOLATED SUPERCELLULAR STRICTURES WITH LARGE HAIL BEING
THE MAIN THREAT. MAIN LIMITING FACTOR WILL BE STORM COVERAGE AS
SOME CAMS DO NOT PRODUCE ANY STORMS. THAT SAID ANYTHING THAT DOES
DEVELOP WILL HAVE THE CHANCE TO BECOME SEVERE. HAVE UPDATED POP
GRIDS WITH CURRENT TIMING AND CHANGED THE SKY GRIDS AS WELL. NO
OTHER CHANGES ARE EXPECTED AT THIS TIME.
&&
.SYNOPSIS...
ISSUED AT 315 AM CDT MON APR 25 2016
LOW PRESSURE WAS LOCATED IN EXTREME EASTERN SD WITH A WARM FRONT
INTO SOUTHERN WI AND A COLD FRONT EXTENDING FROM THE LOW INTO
EXTREME EASTERN NEB AND THEN TO SW KS. LINE OF THUNDERSTORMS THAT
WAS IN CENTRAL IA EARLIER IN THE NIGHT HAS RAPIDLY DECAYED THE
PAST COUPLE OF HOURS TO ONLY A FEW SHOWERS. THIS IS DUE TO A MUCH
MORE STABLE AIRMASS OVER THE DVN CWA AND LACK OF SHEAR.
TEMPERATURES WERE MILD EARLY THIS MORNING AS EXPECTED WITH A
STEADY SOUTH WIND AND CLOUD COVER. 3 AM TEMPERATURES WERE MAINLY
IN THE LOWER TO MID 60S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CDT MON APR 25 2016
FORECAST FOCUS ON THE POTENTIAL FOR ISOLATED STRONG OR SEVERE
THUNDERSTORMS LATER TODAY.
TODAY...WHAT FEW SHOWERS THERE ARE EARLY THIS MORNING WILL
CONTINUE TO FADE AWAY LEAVING THE MORNING HOURS (AFTER 6 AM) DRY.
THEN THE FOCUS WILL BE ON IF ANY CONVECTION CAN ERUPT LATER THIS
AFTERNOON AND EVENING. LOW PRESSURE WILL TRACK ACROSS SOUTHERN MN
AND BE NEAR LA CROSSE WI BY EVENING. A WEAK COLD FRONT WILL DRAG
SOUTHEAST INTO THE DVN CWA THIS AFTERNOON. AHEAD OF THE FRONT
TEMPERATURES SHOULD WARM INTO THE UPPER 70S TO LOWER 80S. WITH
DEWPOINTS IN THE MID 50S TO AROUND 60 THIS SHOULD YIELD MUCAPES OF
ABOUT 2000 J/KG AND MLCAPE TO 1000 J/KG. A 50 KNOT MID LEVEL WIND
MAX WILL APPROACH THE AREA AT PEAK HEATING WITH MODERATE DEEP
LAYER SHEAR OF 40 KNOTS. ANY STORMS DEVELOPING IN THIS ENVIRONMENT
SHOULD BE ABLE TO PRODUCE LARGE HAIL AND DAMAGING WINDS.
HOWEVER...THE BIG PROBLEM IS THE LACK OF SUFFICIENT CONVERGENCE
NEAR THE FRONT AS THE WINDS VEER UNIDIRECTIONAL FROM THE SOUTHWEST.
THE HRRR KEEPS THE CONVECTION IN WI CLOSER TO THE SURFACE LOW AND
BETTER FORCING WHILE THE SPC 4.0 KM WRF-NMM FIRES UP CONVECTION
EAST OF THE MS RIVER NOT UNTIL THIS EVENING. THEREFORE...HAVE
KEPT MENTION OF CHANCE POPS IN THE 20-40 PERCENT RANGE AND MAINLY
ALONG AND EAST OF THE MS RIVER LATER THIS AFTERNOON AND EVENING...
AHEAD OF THE FRONT. SPC DOES HAVE A SLIGHT RISK EAST OF THE MS RIVER.
AT THIS TIME WILL KEEP COVERAGE OF THE STORMS TO ISOLATED TO
SCATTERED BUT THE POTENTIAL IS THERE FOR A DRY FROPA...AND LET DAY
SHIFT MONITOR TRENDS.
TONIGHT...ASSUMING CONVECTION FORMS LATER THIS AFTERNOON AND
EVENING THE FRONT WILL HAVE PUSHED EAST OF THE DVN CWA BY LATE
EVENING ENDING ANY RAIN CHANCES. WEST WINDS SHOULD BRING SOMEWHAT
DRIER AIR INTO THE CWA SO LOWS TONIGHT WILL BE COOLER...IN THE 50S.
SKIES WILL BECOME CLEAR OR PARTLY CLOUDY BEHIND THE FRONT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 315 AM CDT MON APR 25 2016
THE FORECAST OF VERY ACTIVE SYNOPTIC PROGRESSIVE LOW PRESSURE
SYSTEMS REMAINS FORECAST BY ALL GLOBAL MODELS TONIGHT FOR THE
EXTENDED FORECAST. THE TREND THAT THESE SYSTEMS WILL PASS JUST SOUTH
OF OUR CWA...OR THROUGH OUR SOUTHERN CWA CONTINUES TO SUGGEST
EXTENDED PERIODS OF NEAR 100 PERCENT POPS WILL BE REQUIRED FOR LATE
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT AND POSSIBLY THURSDAY. ANOTHER
SYSTEM ON THE HEELS OF THE DEPARTING THURSDAY LOW APPEARS SIMILAR
WITH WIDESPREAD STRATIFORM RAIN/EMBEDDED THUNDER FOR LATE FRIDAY
NIGHT THROUGH THE ENTIRE UPCOMING WEEKEND AND POSSIBLY EARLY WEEK
AHEAD. THAT SYSTEM AS THE MOMENT IS SUGGESTED TO END THE PROGRESSIVE
NATURE OF THE SYNOPTIC FLOW...AND CUT OFF INTO A BROAD UPPER LOW
OVER THE EASTERN HALF OF THE CONUS. THIS IS THE CASE IN BOTH THE GFS
AND EC 00Z RUNS. IN ANY CASE...RAIN...AND PLENTY OF IT....IS
FORECAST THIS UPCOMING WEEK...WITH SOME BOUTS OF EMBEDDED THUNDER
LIKELY AS WELL DURING PERIODS OF STRONG WARM ADVECTION ALOFT.
AT THE TIME...WHILE THE WEEK LONG PERIOD OFFERS THE POTENTIAL FOR
WIDESPREAD 1 TO 2 INCHES OF RAIN...WITH SOME AREAS POSSIBLY SEEING
MORE IN MESOSCALE BANDS OF ACTIVITY. THE RAINFALL RATES OVER ALL
SEEM TO OFFER A SOMEWHAT MORE BENIGN FLASH FLOODING FORECAST...AND
A SLOWLY EVOLVING RIVER RISE POTENTIAL.
TEMPERATURES TUESDAY UNDER SHORT TERM HIGH PRESSURE AND LITTLE COLD
ADVECTION SHOULD TOP OUT WELL INTO THE 70S...MAKING FOR A CERTAIN
CANDIDATE FOR THE MOST PLEASANT DAY THIS WEEK. ONCE RAIN AND CLOUDS
ARRIVE TUESDAY NIGHT...THE NEXT DRY DAY WITH ANY PREDICTABILITY MAY
BE FRIDAY. WEDNESDAY THROUGH THURSDAY WILL SEE FAR COLDER
TEMPERATURES AS IN THE LOWER 50S TO LOWER 60S FROM NORTH TO
SOUTH...AS RAIN COOLED AIR PERSISTS NORTH OF THE WARM FRONT. AT THIS
TIME...IT APPEARS THE WET AND CLOUDY WEATHER WILL KEEP US WELL BELOW
NORMAL WELL INTO NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1214 PM CDT MON APR 25 2016
MVFR CONDITIONS WILL GIVE WAY TO VFR THIS AFTERNOON AND EVENING AS
A COLD FRONT PUSHES THROUGH THE AREA. THE MVFR CIGS AT CID AND DBQ
WILL NOT LAST MUCH LONGER AS THIS FIELD WILL BREAK UP INTO A BAND
CU TO TCU. EAST OF THE MISSISSIPPI RIVER....THUNDERSTORMS ARE
EXPECTED TODAY. TOMORROW AM...GUIDANCE IS HINTING AT MVFR FOG AND
EVEN LOW MVFR CIGS. THINK DBQ HAS THE BEST CHANCE FOR THIS AT THIS
TIME. IT IS POSSIBLE THAT CID MAY NEED TO HAVE THIS INCLUDED IN
LATER TAF ISSUANCES.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...GIBBS
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...ERVIN
AVIATION...GIBBS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
427 PM EDT MON APR 25 2016
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 427 PM EDT MON APR 25 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A WELL-DEFINED...BUT
WEAKENING SHORTWAVE MOVING INTO NRN WI. WITH WEAK SRN STREAM RIDGING
OVER THE SE CONUS AND A TROF CONTINUING TO PERSIST IN SE CANADA...
THE SHORTWAVE IS BEGINNING TO SHEAR EASTWARD INTO THE CONFLUENT FLOW
BTWN THE RIDGE AND TROF. RAIN THAT LIFTED THRU THE FCST AREA LAST
NIGHT WAS REPLACED BY SCT SHOWERY PCPN DURING THE MORNING UNDER A
PUSH OF MID LEVEL DRYING. THIS AFTN...APPROACHING DYNAMICS
ASSOCIATED WITH SHEARING SHORTWAVE HAS LED TO MORE ORGANIZED BANDS
OF SHRA AND EVEN EMBEDDED THUNDER LIFTING ACROSS THE AREA. SOO
WEBCAMS HAVE SHOWN SOME SNOW OCCURRING TODAY WITH EVEN A LITTLE
ACCUMULATION. FARTHER W...KERY OB HAS INDICATED SNOW AS PTYPE AT
TIMES WITH SFC TEMP OF 33 TO 34 DEGREES. PROBABLY CAN`T RULE IT
OUT...BUT MODEL FCST SOUNDINGS UNANIMOUSLY DON`T SUPPORT SNOW AT
KERY. UNDER CLOUDS AND PCPN...IT`S BEEN ANOTHER CHILLY DAY ACROSS
THE AREA WITH CURRENT TEMPS IN THE UPPER 30S TO AROUND 40F.
TONIGHT...SHORTWAVE OVER NRN WI WILL RAPIDLY WEAKEN AS IT SHEARS E
ACROSS THE UPPER GREAT LAKES. WITH WEAKENING DYNAMIC SUPPORT...PCPN
COVERAGE/INTENSITY WILL GRADUALLY DIMINISH. GIVEN ONGOING THUNDER
JUST AHEAD OF SHORTWAVE...WILL CARRY A MENTION OF THUNDER OVER
ROUGHLY THE S HALF OF THE FCST AREA INTO THE EARLY EVENING.
OTHERWISE...WITH THE ARRIVAL OF COLDER AIR AS LOW-LEVEL WINDS BACK
MORE TO THE NE...MODEL GUIDANCE CONTINUES TO HINT THAT THE PCPN WILL
AT LEAST MIX WITH SOME SNOW BEFORE ENDING...ESPECIALLY OVER THE NRN
TIER AS LOW-LEVEL TEMP PROFILE FALLS AOB 0C. MIGHT SEE A DUSTING OF
SNOW ON GRASSY SURFACES. IF CHANGEOVER IS A LITTLE QUICKER...THERE
COULD BE AN INCH OR TWO OF ACCUMULATION.
SOME PATCHY -SN MAY LINGER OVER THE NCNTRL EARLY TUE MORNING.
OTHERWISE...RATHER SHARP CLEARING LINE NOTED THIS AFTN ACROSS NRN
ONTARIO...JUST N OF LAKE SUPERIOR...IS SIGN OF WHAT`S TO COME ON
TUE. AS HAS BEEN THE CASE THE LAST COUPLE OF DAYS...MODELS SHOW
DRAMATIC DRYING OF THE COLUMN FROM N TO S TUE MORNING...WHICH LOOKS
QUITE REASONABLE BASED ON CONDITIONS UPSTREAM. HOWEVER...MODELS DO
SHOW SHEARED OUT VORTICITY PASSING ALONG OR JUST S OF THE MI/WI
BORDER...AND THIS MAY RESULT IN SOME MID CLOUDS ACROSS THE S THRU
THE DAY. DESPITE INCREASING SUNSHINE...GRADIENT NE WIND AND 850MB
TEMPS OF -1 TO -3C AT MIDDAY WILL KEEP CONDITIONS COOL...ESPECIALLY
CLOSER TO LAKE SUPERIOR WHERE TEMPS WILL ONLY RISE TO AROUND 40F.
WELL INLAND...TEMPS SHOULD RISE TO AROUND 50F.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 236 PM EDT MON APR 25 2016
SFC HIGH PRESSURE WILL REMAIN IN CONTROL THROUGH THE EXTENDED...WITH
ONLY A COUPLE MINIMAL CHANCES FOR RAIN. POTENTIAL FOR A SHORTWAVE TO
BRING SOME LIGHT RAIN SHOWERS TO THE SCENTRAL LATE WED NIGHT AND
THU...BUT CONFIDENCE IS LOW. THE OTHER CHANCE FOR RAIN IS OVER THE
SRN CWA SUN INTO NEXT MON...BUT MODELS DISAGREE SUBSTANTIALLY AND
ARE ALSO VARIABLE RUN TO RUN...SO POPS WILL BE SLIGHT CHANCE AT BEST.
TEMPS WILL BE MILD WITH HIGHS FROM THE MID 40S TO MAYBE UPPER
50S...COOLEST NEAR LAKE SUPERIOR. LOWS WILL GENERALLY RANGE FROM THE
MID 20S INTERIOR TO MID 30S NEAR THE GREAT LAKES...COOLEST TEMPS
DOWN TO THE LOW-MID 20S ON TUE NIGHT. SKIES WILL BE PARTLY CLOUDY TO
MOSTLY SUNNY FOR THE MOST PART...WITH MORE CLOUDS WHERE/IF PRECIP
DEVELOPS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 142 PM EDT MON APR 25 2016
WITH PERIODS OF RAIN AND A SHALLOW E FLOW OF CHILLY...MOIST AIR TO
THE N OF A WEAKENING WAVE OF LOW PRES TRACKING E ACROSS WI TO LWR MI
LATER THIS AFTN AND TONIGHT...EXPECT IFR/LIFR CONDITIONS TO DOMINATE
KIWD/KCMX/KSAW THRU TONIGHT. AS SLIGHTLY COLDER AIR ARRIVES
TONIGHT...RAIN MAY MIX WITH OR CHANGE TO SNOW FOR A TIME AT
KCMX/KSAW BEFORE ENDING. STRONG DRYING WILL OCCUR TUE MORNING...
RESULTING IN QUICK IMPROVEMENT TO VFR AS LOW CLOUDS CLEAR
OUT...BEGINNING FIRST AT KCMX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 427 PM EDT MON APR 25 2016
WITH HIGH PRES BUILDING INTO NORTHERN ONTARIO AND WEAKENING LOW PRES
TRACKING ACROSS WI TO SOUTHERN LWR MI...STRONG E TO NE WINDS WILL BE
THE RULE ACROSS LAKE SUPERIOR TONIGHT. OVER THE WESTERN LAKE WHERE
COASTAL CONVERGENCE/FUNNELING ENHANCE E TO NE WINDS...GALE FORCE
WINDS ARE EXPECTED THROUGH THIS EVENING. ACROSS THE REST OF LAKE
SUPERIOR...PLAN FOR WINDS OF 20-30KT...WITH A FEW GALE FORCE GUSTS
INTO SCNTRL LAKE SUPERIOR. AS THE PRES GRADIENT BEGINS TO WEAKEN
OVERNIGHT...WINDS WILL BEGIN TO DIMINISH. WINDS WILL CONTINUE TO
DIMINISH TUE INTO TUE NIGHT AS THE NORTHERN ONTARIO HIGH PRES BUILDS
INTO THE UPPER LAKES. E TO NE WINDS GENERALLY UNDER 20KT WILL
PREVAIL WED...THOUGH GUSTS TO 25 KTS MAY OCCUR OVER WRN LAKE
SUPERIOR. WINDS WILL GENERALLY REMAIN UNDER 20KT THU-SAT ACROSS
THE LAKE AS HIGH PRES SETTLES OVER THE AREA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EDT /MIDNIGHT CDT/ TUESDAY FOR LSZ162-
263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
236 PM EDT MON APR 25 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 422 AM EDT MON APR 25 2016
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CONFLUENT NW FLOW
ALF INTO THE UPR LKS BTWN NRN BRANCH CLOSED LO OVER NRN QUEBEC AND A
SRN BRANCH SHRTWV OVER THE WRN GREAT LKS AHEAD OF STRONG SHRTWV
MOVING SLOWLY ENEWD THRU THE NCENTRAL PLAINS. ALTHOUGH MOISTER
AIR...WITH 00Z PWATS AS HI AS 1.16 INCH AT MPX /ALMOST 250 PCT OF
NORMAL/ AND 0.92 INCH AT GRB /190 PCT OF NORMAL/...HAS PUSHED
FARTHER N AHEAD OF THIS SHRTWV AND SFC/H85 LO OVER ERN SDAKOTA...
DRIER AIR ON THE SRN FLANK OF BONE DRY AIRMASS IN ONTARIO /WHERE 00Z
PWAT AT YPL WAS ONLY 0.12 INCH/ MAINTAINED BY PROXIMITY OF THE
CONFLUENCE ZN BTWN THE BRANCHES SLOWED THE ARRIVAL OF HEAVIER RA
THAT HAS BEEN FCST RECENTLY. HOWEVER...LATEST RADAR IMAGERY SHOWS A
BAND OF RA N OF A NEARLY STNRY H85 WARM FNT STRETCHING FM CENTRAL MN
ACRS NCENTRAL WI IS PUSHING NE THRU UPR MI. UPR DVGC IN RRQ OF 120KT
H3 JET MAX OVER SW QUEBEC AS WELL AS SHARP H85-7 FGEN N OF THE ARPCHG
WARM FNT APPEAR TO BE SGNFT FORCING MECHANISMS. BUT THIS BAND IS
RATHER NARROW...WITH DRY SLOTTING IN ADVANCE OF THE APRCHG SHRTWV
CAUSING A SHARP SRN EDGE TO THIS BAND OF HEAVIER RA THAT IS ALREADY
PUSHING N ACRS THE WI BORDER.
MAIN FCST CONCERNS THRU TNGT FOCUS ON POPS/QPF TODAY AHEAD OF SLOWLY
APRCHG SHRTWV AND THEN DRYING TRENDS/POTENTIAL FOR SOME SN TNGT AS
LARGE SCALE SUBSIDENCE/SOMEWHAT COLDER AIR FOLLOW IN THE WAKE OF
SHEARING SHRTWV THRU WI.
TODAY...MODELS IN GOOD AGREEMENT SHOWING BAND OF HEAVIER RA
CONTINUING NE THRU THE CWA BUT TENDING TO DIMINISH AS THE FGEN
FORCING WEAKENS AS THIS BAND MOVES FARTHER N INTO LINGERING DRY AIR
MAINTAINED BY NW FLOW ALF OVER ONTARIO AND AWAY FM NEARLY STNRY FNT
LINGERING IN WI. THEN SOME DRY SLOTTING WILL IMPACT MAINLY THE
SCENTRAL BEFORE DPVA/LARGER SCALE QVECTOR CNVGC IN ADVANCE OF THE
APRCHG SHRTWV ARRIVE W-E AND CAUSE THE PCPN AREA TO EXPAND AGAIN/
INTENSIFY IN THE AFTN. WITH CLD COVER/RA...WL MAINTAIN PREVIOUS FCST
WELL BLO NORMAL MAX TEMPS NOT FAR FM 40.
TNGT...SHRTWV SLIDING ENEWD IS PROGGED TO SHEAR OUT AND MOVE MORE
QUICKLY TO THE E ACRS WI AS IT ENTERS THE UPR CONFLUENCE ZN BTWN THE
NRN AND SRN BRANCHES. WITH DIMINISHING DYNAMIC SUPPORT/MID LVL
DRYING ACCOMPANYING THE SHEARING SHRTWV...EXPECT PCPN COVERAGE/
INTENSITY TO GRDLY DIMINISH. WITH THE ARRIVAL OF COLDER AIR AS THE
LLVL FLOW BACKS MORE TO THE NE...GUIDANCE HINTS THE PCPN WL AT LEAST
MIX WITH SOME SN BEFORE ENDING ESPECIALLY OVER THE NRN TIER AS H85
TEMPS FALL AOB 0C. THE NAM INDICATES SEVERAL INCHES OF WET SN COULD
ACCUMULATE OVER THE HIER TERRAIN OF THE NCNTRL WITH LINGERING SLGTLY
CYC NE UPSLOPE FLOW AIDING COOLING/LIFT. THIS MODEL IS SLOWER THAN
MOST OF THE OTHER GUIDANCE IN SHEARING OUT THE SHRTWV/BRINGING IN
LARGER SCALE QVECTOR DVGC/HOLDING ON TO LLVL CYC FLOW. BUT SINCE
SOME OF THE OTHER HI RES MODELS INDICATE SOME PERSISTENT HIER QPF
OVER THE HIER TERRAIN OF THE NCENTRAL...WL MAINTAIN SOME HIER POPS
IN THIS AREA ALONG WITH A HIER QPF.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 236 PM EDT MON APR 25 2016
SFC HIGH PRESSURE WILL REMAIN IN CONTROL THROUGH THE EXTENDED...WITH
ONLY A COUPLE MINIMAL CHANCES FOR RAIN. POTENTIAL FOR A SHORTWAVE TO
BRING SOME LIGHT RAIN SHOWERS TO THE SCENTRAL LATE WED NIGHT AND
THU...BUT CONFIDENCE IS LOW. THE OTHER CHANCE FOR RAIN IS OVER THE
SRN CWA SUN INTO NEXT MON...BUT MODELS DISAGREE SUBSTANTIALLY AND
ARE ALSO VARIABLE RUN TO RUN...SO POPS WILL BE SLIGHT CHANCE AT BEST.
TEMPS WILL BE MILD WITH HIGHS FROM THE MID 40S TO MAYBE UPPER
50S...COOLEST NEAR LAKE SUPERIOR. LOWS WILL GENERALLY RANGE FROM THE
MID 20S INTERIOR TO MID 30S NEAR THE GREAT LAKES...COOLEST TEMPS
DOWN TO THE LOW-MID 20S ON TUE NIGHT. SKIES WILL BE PARTLY CLOUDY TO
MOSTLY SUNNY FOR THE MOST PART...WITH MORE CLOUDS WHERE/IF PRECIP
DEVELOPS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 142 PM EDT MON APR 25 2016
WITH PERIODS OF RAIN AND A SHALLOW E FLOW OF CHILLY...MOIST AIR TO
THE N OF A WEAKENING WAVE OF LOW PRES TRACKING E ACROSS WI TO LWR MI
LATER THIS AFTN AND TONIGHT...EXPECT IFR/LIFR CONDITIONS TO DOMINATE
KIWD/KCMX/KSAW THRU TONIGHT. AS SLIGHTLY COLDER AIR ARRIVES
TONIGHT...RAIN MAY MIX WITH OR CHANGE TO SNOW FOR A TIME AT
KCMX/KSAW BEFORE ENDING. STRONG DRYING WILL OCCUR TUE MORNING...
RESULTING IN QUICK IMPROVEMENT TO VFR AS LOW CLOUDS CLEAR
OUT...BEGINNING FIRST AT KCMX.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 AM EDT MON APR 25 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 INTO TONIGHT. OVER THE
WESTERN LAKE WHERE COASTAL CONVERGENCE/FUNNELING ENHANCE E TO NE
WINDS...GALE FORCE WINDS ARE EXPECTED THROUGH THIS EVENING. ACROSS
THE REST OF LAKE SUPERIOR...PLAN FOR WINDS OF 20-30KT. WINDS WILL
SLOWLY DIMINISH LATE TONIGHT/TUE MORNING...BUT MORE SO TUE NIGHT AS
THE NORTHERN ONTARIO HIGH PRES BUILDS INTO THE UPPER LAKES. E TO NE
WINDS GENERALLY UNDER 20KT WILL PREVAIL WED...THOUGH GUSTS TO 25 KTS
MAY OCCUR OVER WRN LAKE SUPERIOR. WINDS WILL DIMINISH TO LESS THAN
20KT THU/FRI ACROSS THE ENTIRE LAKE AS HIGH PRES SETTLES OVER THE
AREA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EDT /MIDNIGHT CDT/ TUESDAY FOR LSZ162-
263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
143 PM EDT MON APR 25 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 422 AM EDT MON APR 25 2016
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CONFLUENT NW FLOW
ALF INTO THE UPR LKS BTWN NRN BRANCH CLOSED LO OVER NRN QUEBEC AND A
SRN BRANCH SHRTWV OVER THE WRN GREAT LKS AHEAD OF STRONG SHRTWV
MOVING SLOWLY ENEWD THRU THE NCENTRAL PLAINS. ALTHOUGH MOISTER
AIR...WITH 00Z PWATS AS HI AS 1.16 INCH AT MPX /ALMOST 250 PCT OF
NORMAL/ AND 0.92 INCH AT GRB /190 PCT OF NORMAL/...HAS PUSHED
FARTHER N AHEAD OF THIS SHRTWV AND SFC/H85 LO OVER ERN SDAKOTA...
DRIER AIR ON THE SRN FLANK OF BONE DRY AIRMASS IN ONTARIO /WHERE 00Z
PWAT AT YPL WAS ONLY 0.12 INCH/ MAINTAINED BY PROXIMITY OF THE
CONFLUENCE ZN BTWN THE BRANCHES SLOWED THE ARRIVAL OF HEAVIER RA
THAT HAS BEEN FCST RECENTLY. HOWEVER...LATEST RADAR IMAGERY SHOWS A
BAND OF RA N OF A NEARLY STNRY H85 WARM FNT STRETCHING FM CENTRAL MN
ACRS NCENTRAL WI IS PUSHING NE THRU UPR MI. UPR DVGC IN RRQ OF 120KT
H3 JET MAX OVER SW QUEBEC AS WELL AS SHARP H85-7 FGEN N OF THE ARPCHG
WARM FNT APPEAR TO BE SGNFT FORCING MECHANISMS. BUT THIS BAND IS
RATHER NARROW...WITH DRY SLOTTING IN ADVANCE OF THE APRCHG SHRTWV
CAUSING A SHARP SRN EDGE TO THIS BAND OF HEAVIER RA THAT IS ALREADY
PUSHING N ACRS THE WI BORDER.
MAIN FCST CONCERNS THRU TNGT FOCUS ON POPS/QPF TODAY AHEAD OF SLOWLY
APRCHG SHRTWV AND THEN DRYING TRENDS/POTENTIAL FOR SOME SN TNGT AS
LARGE SCALE SUBSIDENCE/SOMEWHAT COLDER AIR FOLLOW IN THE WAKE OF
SHEARING SHRTWV THRU WI.
TODAY...MODELS IN GOOD AGREEMENT SHOWING BAND OF HEAVIER RA
CONTINUING NE THRU THE CWA BUT TENDING TO DIMINISH AS THE FGEN
FORCING WEAKENS AS THIS BAND MOVES FARTHER N INTO LINGERING DRY AIR
MAINTAINED BY NW FLOW ALF OVER ONTARIO AND AWAY FM NEARLY STNRY FNT
LINGERING IN WI. THEN SOME DRY SLOTTING WILL IMPACT MAINLY THE
SCENTRAL BEFORE DPVA/LARGER SCALE QVECTOR CNVGC IN ADVANCE OF THE
APRCHG SHRTWV ARRIVE W-E AND CAUSE THE PCPN AREA TO EXPAND AGAIN/
INTENSIFY IN THE AFTN. WITH CLD COVER/RA...WL MAINTAIN PREVIOUS FCST
WELL BLO NORMAL MAX TEMPS NOT FAR FM 40.
TNGT...SHRTWV SLIDING ENEWD IS PROGGED TO SHEAR OUT AND MOVE MORE
QUICKLY TO THE E ACRS WI AS IT ENTERS THE UPR CONFLUENCE ZN BTWN THE
NRN AND SRN BRANCHES. WITH DIMINISHING DYNAMIC SUPPORT/MID LVL
DRYING ACCOMPANYING THE SHEARING SHRTWV...EXPECT PCPN COVERAGE/
INTENSITY TO GRDLY DIMINISH. WITH THE ARRIVAL OF COLDER AIR AS THE
LLVL FLOW BACKS MORE TO THE NE...GUIDANCE HINTS THE PCPN WL AT LEAST
MIX WITH SOME SN BEFORE ENDING ESPECIALLY OVER THE NRN TIER AS H85
TEMPS FALL AOB 0C. THE NAM INDICATES SEVERAL INCHES OF WET SN COULD
ACCUMULATE OVER THE HIER TERRAIN OF THE NCNTRL WITH LINGERING SLGTLY
CYC NE UPSLOPE FLOW AIDING COOLING/LIFT. THIS MODEL IS SLOWER THAN
MOST OF THE OTHER GUIDANCE IN SHEARING OUT THE SHRTWV/BRINGING IN
LARGER SCALE QVECTOR DVGC/HOLDING ON TO LLVL CYC FLOW. BUT SINCE
SOME OF THE OTHER HI RES MODELS INDICATE SOME PERSISTENT HIER QPF
OVER THE HIER TERRAIN OF THE NCENTRAL...WL MAINTAIN SOME HIER POPS
IN THIS AREA ALONG WITH A HIER QPF.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 349 AM EDT MON APR 25 2016
UPPER AIR PATTERN WILL FEATURE A COLD UPPER LEVEL TROUGH CENTERED
OVER QUEBEC MOST OF THIS WEEK WITH TROUGHING OVER WESTERN CONUS.
UPPER LAKES WILL RESIDE WITHIN CONFLUENT NW FLOW ALOFT ON EDGE OF
EASTERN CANADA TROUGH. RESULT IS HIGH PRESSURE EXPANDING OVER HUDSON
BAY EARLY THIS WEEK WILL PUSH A RIDGE OVER UPPER GREAT LAKES INTO
NEXT WEEKEND. PATTERN WILL LEAD TO DRY WEATHER WITH SEASONABLY COOL
TEMPERATURES. NO REAL SIGNIFICANT WARM UP IS IN SIGHT ATTM. IN FACT
IF ANYTHING THE 7-10 DAY PERIOD JUST BEYOND REACH OF THIS FORECAST
POINTS TO MORE COOLER AND UNSETTLED PATTERN AS TROUGHING OVER
WESTERN CONUS EVENTUALLY MAKES IT TO THE GREAT LAKES. EXTRAPOLATING
CPC DAY 8-14 OUTLOOK MADE ON APRIL 24TH SUGGESTS THAT WARMER AIR MAY
BEGIN TO MAKE ITS WAY OVER GREAT LAKES TOWARD MID MAY AND CPC 3-4
WEEK OUTLOOK GOOD THROUGH MID-LATE MAY SIGNALS A SWITCH TO ABOVE
NORMAL TEMPS. TIME WILL TELL IF THAT DOES INDEED OCCUR.
LINGERING EFFECTS FROM DEPARTING LOW PRESSURE SYSTEM ARE FEW BUT
COULD SHOW UP AS A FEW RAIN/SNOW SHOWERS EARLY ON TUESDAY...MAINLY
FOR UPSLOPE AREAS OF CNTRL CWA. AT THE LEAST...INCREASED SKY COVER
UNTIL LATE MORNING WHEN DRY AIR WITH THE HIGH BUILDING TO THE NORTH
SHOULD ERODE LOW CLOUDS STEADILY FROM NORTH TO SOUTH. SMATTERING OF
MID OR HIGH CLOUDS MAY TRY TO LINGER OVER SOUTHERN CWA...BUT OVERALL
SHOULD TURN INTO A MOSTLY SUNNY DAY FOR ALL CWA.
NO REAL SIGNIFICANT FORECAST ISSUES REST OF THIS WEEK AS THE HIGH
PRESSURE DOMINATES. SKIES SHOULD BE MOSTLY CLEAR AND WINDS NOT
PARTICULARLY STRONG/GUSTY. GRADIENT ONSHORE NORTHEAST WINDS OUT OF
THE HIGH WILL KEEP LAKE SUPERIOR SHORELINE COOLEST WITH DAYTIME
HIGHS MAINLY IN THE 40S. ELSEWHERE...TEMPS SHOULD GRADUALLY RISE
THROUGH THE 50S BY LATE WEEK. PERHAPS MAY SEE LOWER 60S WELL INLAND
FROM THE GREAT LAKES SHORES BY LATE THIS WEEK INTO NEXT WEEKEND...
BUT THAT WOULD ONLY COME FROM AIRMASS MODERATION AS THE OVERALL
TEMPS ALOFT WARM LITTLE. THE COOL AND DRY AIR MASS WITH THE HIGH
POINTS TO GOING ON LOWER END OF GUIDANCE FOR NIGHTTIME LOWS
ESPECIALLY INLAND.
CONSENSUS OF MODELS BRINGS SLIGHT CHANCES BACK OVER UPR MICHIGAN
NEXT SUNDAY. PREVIOUS ECMWF DROVE THOSE RELATIVELY HIGHER POPS...BUT
LATEST RUN HAS TRENDED FARTHER SOUTH WITH SFC-MID LEVEL LOW LIFTING
ACROSS MID MISSISSIPPI RIVER VALLEY. FARTHER SOUTH TREND WITH PRECIP
MAKES SENSE GIVEN THE STRONG/PERSISTENT/DRY HUDSON BAY HIGH THE
SYSTEM WILL BE RUNNING INTO.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 142 PM EDT MON APR 25 2016
WITH PERIODS OF RAIN AND A SHALLOW E FLOW OF CHILLY...MOIST AIR TO
THE N OF A WEAKENING WAVE OF LOW PRES TRACKING E ACROSS WI TO LWR MI
LATER THIS AFTN AND TONIGHT...EXPECT IFR/LIFR CONDITIONS TO DOMINATE
KIWD/KCMX/KSAW THRU TONIGHT. AS SLIGHTLY COLDER AIR ARRIVES
TONIGHT...RAIN MAY MIX WITH OR CHANGE TO SNOW FOR A TIME AT
KCMX/KSAW BEFORE ENDING. STRONG DRYING WILL OCCUR TUE MORNING...
RESULTING IN QUICK IMPROVEMENT TO VFR AS LOW CLOUDS CLEAR
OUT...BEGINNING FIRST AT KCMX.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 AM EDT MON APR 25 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 INTO TONIGHT. OVER THE
WESTERN LAKE WHERE COASTAL CONVERGENCE/FUNNELING ENHANCE E TO NE
WINDS...GALE FORCE WINDS ARE EXPECTED THROUGH THIS EVENING. ACROSS
THE REST OF LAKE SUPERIOR...PLAN FOR WINDS OF 20-30KT. WINDS WILL
SLOWLY DIMINISH LATE TONIGHT/TUE MORNING...BUT MORE SO TUE NIGHT AS
THE NORTHERN ONTARIO HIGH PRES BUILDS INTO THE UPPER LAKES. E TO NE
WINDS GENERALLY UNDER 20KT WILL PREVAIL WED...THOUGH GUSTS TO 25 KTS
MAY OCCUR OVER WRN LAKE SUPERIOR. WINDS WILL DIMINISH TO LESS THAN
20KT THU/FRI ACROSS THE ENTIRE LAKE AS HIGH PRES SETTLES OVER THE
AREA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EDT /MIDNIGHT CDT/ TUESDAY FOR LSZ162-
263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...JLA
Area Forecast Discussion
National Weather Service Springfield MO
332 PM CDT MON APR 25 2016
...Strong to Severe Storms Tuesday Afternoon Through Wednesday
Across Southeast Kansas and the Missouri Ozarks Region.
.SHORT TERM...(This evening through Tonight)
Issued at 255 PM CDT Mon Apr 25 2016
Cloud cover was eroding this afternoon as a warm and moist
airmass continues to spread into the area. A very mild evening is
in store as southerly winds will continue. A 40kt 850 llj will
develop overnight across NE Oklahoma and Northern AR. This will
interact with a developing warm front along Central Missouri to
cause isolated to scattered showers and thunderstorms to form overnight.
High res models show this activity moving east southeastward
across locations mainly along and north of US Highway 54 overnight
closer to the boundary. A strong CAP will be in place across most
of the area. Elevated instability will be ample with progged MU
CAPEs of 2000-3000j/kg across the area. Wind shear will be
marginal however with 0-6km bulk wind shear of 30kts. So a
marginal severe storm threat is possible with any storm that can
become rooted above 850mb with large hail to the size of quarters
becoming the main threat. Models show this activity remaining
north of Interstate 44 during the early morning hours Tuesday
before shifting eastward.
.LONG TERM...(Tuesday through Monday)
Issued at 255 PM CDT Mon Apr 25 2016
Confidence is increasing that we will see an active severe
weather day across portions of the Central Plains moving into the
Ozarks Region on Tuesday afternoon and night. All eyes will be on
the area just west of the Missouri Ozarks across central and
eastern Kansas...including area down into central Oklahoma.
Forecast models are coming into agreement with an outbreak of
severe weather developing by late Tuesday afternoon and evening
moving into Missouri by late evening.
Interesting that the high resolution models suggest that
supercells and line segments will develop a little further east
across eastern Kansas into eastern Oklahoma by 21z to 00z well
ahead of the dryline. The forecast atmospheric ingredients will
include MLCAPE from 3000 to 5000 J/KG...Shear from 35 to 45
knots...decent height falls. There will be a strong cap initially but
will be overcome by the evening hours. Supercells will develop out
west of our area and move east-northeast during the evening. We
expected these storms to begin to impact our southeast Kansas
counties and extreme western Missouri along the I-49 between 5 pm
to 9 pm. This area will have the greatest potential for a tornado
threat along with damaging wind gusts and very large hail up to
golf ball size. Residents in these area should to stay weather
aware tomorrow evening.
This area of severe storms will eventually form into a line
segments as it moves across the I-49 corridor further into the
Missouri Ozarks late tomorrow evening and night. The severe
weather risk will transition into more of a damaging wind threat
and large hail but can`t rule out a brief spin of tornado
potential during the late evening and overnight hours for the
Missouri Ozarks region. We will also mention a very limited
threat for localized heavy rainfall and flash flooding of a low
water crossing or two. This will be where any thunderstorm may
train over the same area a little longer.
This line will eventually move into the eastern Ozarks by very
early Wednesday morning. The question that remains is how much we
will be able to destabilize Wednesday afternoon and evening for
another round of severe weather potential across the eastern
Ozarks. SPC has the eastern half of the area under a slight risk. The
main threat for Wednesday afternoon and evening will be damaging
wind gusts and large hail. The whole system finally moves out of
the area late Wednesday night.
We will clear out for Thursday and enjoy a nice break from rain
and storms. The next system to move in will be late Friday evening
through Sunday morning. The frontal boundary that will come
through Wednesday will back up as a warm front on Saturday.
Several rounds of showers and thunderstorms are expected over the
weekend with a limited potential for additional strong storms
possible Saturday afternoon and evening. Will also mention the
threat for some locally heavy rainfall possible by the weekend
with 1 to 3 inches possible across the area. The weather pattern
will be active and unsettled this week through the weekend across
the region.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1234 PM CDT Mon Apr 25 2016
MVFR ceilings will persist into the afternoon and SGF and JLN
before slowly lifting this afternoon. LLWS wind shear will remain
possible overnight across SGF and JLN as a strong low level jet
develops across northeast Oklahoma. Ceilings will also lower back
into MVFR after 06z and into IFR by morning. Overnight storms
north of the TAFS may try to move in by morning but confidence is
not high yet on that scenario. IFR/MVFR ceiling will persist
through most of Tuesday morning.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Burchfield
LONG TERM...Griffin
AVIATION...Burchfield
[top]
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
326 PM CDT MON APR 25 2016
.Discussion...
Issued at 325 PM CDT MON APR 25 2016
Active weather is expected over the next few days with several
rounds of severe thunderstorms possible.
For tonight, the cold front that is draped across the area, from
southwest to northeast, is expected to sag to and stall along the I-
70 corridor. A strong low-level jet will develop tonight and
intersect this boundary. The combination of forcing from the front
as well as strong, moist isentropic ascent should lead to showers
and storms developing in the vicinity of the I-70 corridor late
tonight and into tomorrow morning. The intensity of this activity is
a little variable/uncertain but there is good agreement amongst the
models in developing some activity. And given the modest instability
and shear, a few strong to severe storms are possible. These storms
should be elevated so large hail will be the biggest concern.
Depending on their intensity and coverage, these could form into a
convective cluster and generally track to the east/southeast through
Tuesday AM. The WRF-ARW is the most robust with this notion but the
NAM supports this idea as well. The GFS and the WRF-NMM, while they
both develop storms, are weaker with not as widespread coverage and
diminish activity through the morning. It`s likely that the weaker,
lower coverage amount doesn`t produce a sufficient cold pool to
sustain new convection or propagate it significantly away from its
initiation point.
Focus then turns to the Tuesday evening and overnight period. There
may be some dependency of this time frame on what happens earlier in
the day. But even the models that are very robust with convection
recover the atmosphere in time for there to be strong instability
for additional storms during the evening and overnight. While the
most intense convection should initiate over central KS, models show
an area of convergence well ahead of the dryline over eastern KS and
western MO. It`s possible this may be a secondary area of
initiation. Regardless, storms are expected to form into more of a
linear mode with bowing segments. strong low-level shear and
helicity may be supportive of embedded tornadoes but damaging winds
and hail look like more likely impacts. This activity should weaken
by early Wednesday AM but strong to potentially severe storms may be
ongoing through the night into the eastern portions of the forecast
area.
The last element to watch before this system finally lifts away is
during the day Wednesday. Wednesday afternoon looks like a decent
setup for 500 mb closed low tornadoes. The warm front will be draped
across northern MO with decent instability along and to the south of
it. The upper low should be to the west over NE. While the more
classic setup looks to be to our northwest, the strong shear along
the front may lead to a few, relatively tornadoes over northern MO.
The forecast settles down Thursday into Friday, but by Saturday,
another round of storms is expected to affect the area. Models show
another closed upper low sitting to our west, with at least parts of
the forecast area within the warm sector. So more rounds of strong
to potentially severe storms are possible Saturday into Sunday.
&&
.Aviation...(For the 18Z TAFS through 18Z Tuesday Afternoon)
Issued at 1228 PM CDT MON APR 25 2016
MVFR ceilings should persist through the afternoon from the KC area
southward. Trajectory of clouds and slow motion of the front with
ample low level moisture south of the front will help the clouds
persist. For tonight, have added a mention of thunderstorms for area
along the I-70 corridor. Models have some into good agreement
developing convection in this area late tonight into tomorrow
morning. The the placement of storms is still uncertain but as
confidence on a location increase a from group can be added. Then for
tomorrow, it looks like IFR ceilings with robust low level moisture
streaming into the area. This may lift in the afternoon but through
the morning hours it looks like IFR conditions.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...CDB
Aviation...CDB
[top]
Area Forecast Discussion
National Weather Service Saint Louis MO
246 PM CDT MON APR 25 2016
.SHORT TERM... (Through Tuesday)
Issued at 242 PM CDT Mon Apr 25 2016
(Tonight)
Main focus will continue to be on convective trends. Cold front will
come into northern CWA late this evening and stall out across CWA.
Frontal boundary will remain quasi-stationary through Tuesday.
Highest PoPs for tonight in theory should be closely tied to where
low-level warm/moist advection maximizes on nose of anticyclonically
curved portion of LLJ intersects with sfc boundary. Current
expectation is for isolated-scattered activity developing this
evening and lasting through the night tonight. May need higher PoPs
tonight...but uncertainty exists with coverage but also placement of
boundary.
Marginally severe hail will also be possible this evening with any
thunderstorms as well as for portions of central Missouri late
tonight as instability aloft increases.
Temperatures will remain very mild tonight as clouds increase with a
very warm start given today`s highs. Lows for a vast majority of the
area will be in the 60s.
(Tuesday)
Believe scattered showers/storms will be ongoing on Tuesday morning
with the best chances across the southern 2/3 of the CWA. Should be
a lull in the activity late Tuesday morning into early Tuesday
afternoon...though still carried slights due to frontal boundary
remaining across the area. Uncertainty increases for Tuesday
afternoon. Best chance of thunderstorms developing will be
along/near the quasi-stationary front but coverage (if any) is
highly unknown. Mid/upper level ridge builds across area so not
exactly a favorable environment aloft for convective initiation.
However...atmosphere should be very unstable on Tuesday afternoon
with 3000+ J/kg of SBCAPE possible depending on how the morning
activity evolves. So...any storms that do develop would likely go
severe and potentially quickly as well. Deep layer shear is not
impressive (20-25 knots)...though this may be overcome by
instability. Large hail looks to be the primary threat with any
thunderstorms on Tuesday afternoon...with very large hail possible
if any storms can sustain a rotating updraft.
Temperatures on Tuesday will be fairly similar to that of today.
Expectation is for most locations to top off in the low to mid 80s.
Gosselin
.LONG TERM... (Tuesday Night through Next Monday)
Issued at 242 PM CDT Mon Apr 25 2016
Stalled frontal boundary along I-70 corridor to remain the focus for
another round of storms Tuesday night. Models still indicating
possible MCS development as elevated convection fires up and congeals
into a complex, sliding east along boundary. Main severe threat will
be large hail.
Depending on when/if MCS develops will affect what happens on
Wednesday with another round of storms as warm front lifts north and
if there is time for atmosphere to recover. Either way, shear will
increase substantially as the storm system approaches and
instability may not need to be as high as what it was Tuesday anyway
to justify a continuation of a severe risk. For now will see best
chances of storms over northeast MO/west central-southwest IL
Wednesday/Wednesday night.
Models are slower with system as far as moving the surface low and
attendant cold front through region, not exiting til Thursday
morning. Precipitation to slowly taper off on Thursday.
Still looks to be a wet weekend as another system moves in from the
west. This system will be a bit further south than current storm, so
we will be on the cool side with mostly showers and a few
thunderstorms.
As for temperatures this week, will remain above average through
Thursday, then dip down to near normal levels through the weekend
and into early next week.
Byrd
&&
.AVIATION... (For the 18z TAFs through 18z Tuesday Afternoon)
Issued at 1245 PM CDT Mon Apr 25 2016
Main concern through Tuesday afternoon will be on chances of
showers and thunderstorms. Cold front will move into the northern
sections of the forecast area late this evening and eventually
become stationary overnight tonight. Chances of showers/storms
hard to pin down tonight and especially on Tuesday but believe
scattered activity will develop by mid evening and to persist
through the night. Given the uncertainty in timing/placement of
this expected activity...just have VCTS groups in for now.
Consensus of guidance also suggests ceilings lowering into MVFR
overnight tonight and lasting into early Tuesday morning before
lifting.
Complicated scenario for tomorrow. Not sure how much convective activity
will be still ongoing at daybreak but frontal boundary will remain
draped across the CWA on Tuesday. Believe there likely will be a
lull however in activity from late morning to early afternoon.
Additional activity may develop by mid afternoon with the best
chances right along the frontal boundary.
Specifics for KSTL:
Cold front will stall near the terminal late tonight and bring a
chance of showers/storms. Latest HRRR also suggests some scattered
activity a bit earlier along a prefrontal trough though not sure
if this actually will develop. Guidance suggests MVFR ceilings
also coming in around daybreak and lasting into late Tuesday
morning. Convective trends looking into Tuesday are highly
uncertain but with frontal boundary remaining near the
terminal...storms could develop at any time.
Gosselin
&&
.PRELIMINARY POINT TEMPS/POPS...
Saint Louis 68 84 64 78 / 40 40 60 70
Quincy 61 80 59 70 / 20 20 90 80
Columbia 65 81 63 76 / 50 50 80 70
Jefferson City 65 82 63 78 / 40 40 80 70
Salem 64 80 63 74 / 30 30 60 80
Farmington 61 79 62 75 / 20 30 60 70
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
950 AM PDT MON APR 25 2016
.SYNOPSIS...SHOWERS AND ISOLATED THUNDERSTORMS ARE LIKELY TODAY
MAINLY NORTH OF INTERSTATE 40 AS A WEATHER SYSTEM MOVES THROUGH THE
REGION. STRONG WINDS AND PATCHY BLOWING DUST CAN ALSO BE EXPECTED
ESPECIALLY ACROSS THE MOJAVE DESERT AND THE SOUTHERN GREAT BASIN.
IMPROVING CONDITIONS EXPECTED TUESDAY BEFORE ANOTHER WEATHER SYSTEM
MOVES IN MIDWEEK WITH ADDITIONAL SHOWER CHANCES AND ANOTHER ROUND OF
SPRING WINDS.
&&
.UPDATE...UPPER LOW CURRENT PUSHING SOUTHEAST THROUGH CENTRAL NEVADA
WILL CONTINUE TO MOVE INTO UTAH THIS AFTERNOON. SCATTERED LIGHT
SHOWERS HAVE BEEN OCCURRING OVER PORTIONS OF CLARK...LINCOLN AND
WESTERN MOHAVE COUNTIES AND THESE WILL CONTINUE TO MOVE EAST THROUGH
THE DAY. THERE HAVE BEEN A COUPLE OF LIGHTNING STRIKES IN LINCOLN
COUNTY SINCE 9AM WHICH IS CLOSE TO THE LOW CENTER SO ISOLATED
THUNDERSTORMS FOR LINCOLN AND NORTHERN MOHAVE WILL STILL REMAIN A
THREAT THROUGH THE DAY. HOWEVER...AREAS SUCH AS SOUTHERN CLARK AND
SOUTHERN MOHAVE COUNTIES WHICH HAVE BEEN SUN FOR MUCH OF THE MORNING
WILL ALSO SEE A THUNDERSTORM THREAT THIS AFTERNOON.
THE OTHER CONCERN FOR TODAY WILL BE GUSTY WINDS ACROSS THE REGION.
WIND ADVISORIES ARE CURRENTLY IN PLACE FOR PARTS OF SAN
BERNARINO...ESMERALDA...CENTRAL NYE...AND SOUTHERN MOHAVE COUNTIES.
THESE STILL LOOK GOOD AND NO CHANGES WILL BE NEEDED. WINDS COULD
BECOME STRONG ENOUGH OVER WESTERN SAN BERNARDINO COUNTY THIS
AFTERNOON TO PUSH HIGH WIND WARNING CRITERIA...BUT FOR NOW WILL TAKE
A WAIT AND SEE APPROACH. AT THIS TIME FEEL ITS BORDERLINE FOR THAT
TO OCCUR. NEED TO MAKE A FEW CHANGES TO INCREASE POPS OVER SOUTHERN
MOHAVE AND CLARK COUNTIES.
&&
PREV DISCUSSION
250 AM PDT MON APR 25 2016
.SHORT TERM...THROUGH TUESDAY NIGHT.
ITS BEEN AN ACTIVE EVENING AND OVERNIGHT PERIOD TODAY AS A FAIRLY
POTENT TROUGH PIVOTS INTO THE REGION. THIS HAS SPARKED SHOWERS AND
ISOLATED THUNDERSTORMS THROUGH THE NIGHT MAINLY ACROSS INYO COUNTY
AND THE SOUTHERN GREAT BASIN. THUNDERSTORMS NEAR DEATH VALLEY WERE
FAIRLY POTENT FOR A FEW HOURS AFTER SUNSET AS THEY WERE SPARKED BY
SURFACE CONVERGENCE ALONG A SOUTHWARD MOVING COLD FRONT AND AIDED BY
STRONG LIFT IN THE LEFT EXIT REGION OF AN INCOMING JET. THUNDERSTORM
ACTIVITY HAS SINCE WANED WITH NO NEW STRIKES DETECTED IN THE PAST
HOUR...HOWEVER WE REMAIN IN THE FAVORABLY DIFFLUENT LEFT EXIT REGION
OF A 80KT JET AT 300MB....WHICH WILL AID IN ADDITIONAL SHOWER
DEVELOPMENT ACROSS OUR REGION THROUGH THE MORNING HOURS. HIGH RES
GUIDANCE INCLUDING THE HRRR BREAK OUT ADDITIONAL SHOWERS IN SOUTHERN
INYO COUNTY EARLY THIS MORNING AND DRIFT THEM EASTWARD TOWARDS THE
LAS VEGAS VALLEY AROUND SUNRISE. STRONG FORCING AND MARGINAL
INSTABILITY COULD RESULT IN A FEW RUMBLES OF THUNDER AS WELL. GIVEN
THE MODEL AGREEMENT IN THIS PARTICULAR PART OF THE FORECAST
AREA...IVE BOOSTED POPS INTO THE LIKELY CATEGORY FOR THE LAS VEGAS
AREA FOR THE MORNING HOURS. BEWARE OF WET AND SLICK
ROADWAYS...THOUGH IM NOT ANTICIPATING MUCH MORE THAN A FEW
HUNDREDTHS FOR MOST AREAS. OUTSIDE OF FAR SOUTHERN
NEVADA...WIDESPREAD SHOWERS AND ISOLATED THUNDERSTORMS CAN BE
EXPECTED TODAY NORTH OF INTERSTATE 40...PARTICULARLY ACROSS THE
SOUTHERN GREAT BASIN WHERE SOME AREAS MAY PICK UP OVER A QUARTER OF
AN INCH OF PRECIPITATION...AND PERHAPS SOME SLUSHY ACCUMULATIONS OF
SNOW ABOVE 6000 FEET.
ASIDE FROM THE PRECIPITATION...THE OTHER BIG CONCERN IS WIND.
HIGHEST IMPACT AREA FROM WIND WILL BE ACROSS THE WESTERN MOJAVE
DESERT PARTICULARLY NEAR DAGGETT AND BICYCLE LAKE. IVE MAINTAINED
THE WIND ADVISORY FOR THESE AREAS IN FAVOR OF THE WIND SPEEDS
ADVERTISED BY OUR HIGH RES MODELS. HOWEVER...MOS GUIDANCE
PARTICULARLY THE MAV HAS BEEN VERY BULLISH WITH HIGH WINDS IN THE
MID AFTERNOON FOR DAGGETT. SO WE WILL NEED TO KEEP AN EYE ON
IT...BUT I HAVE DISCOUNTED IT FOR NOW SINCE IT HAS RUN TOO HIGH IN
RECENT PAST EVENTS. ANTICIPATE PEAK GUSTS IN THE 50 TO 55 MPH RANGE
FOR MOST AREAS IN THE WESTERN MOJAVE DESERT....THOUGH A COUPLE
ISOLATED LOCATIONS MAY EXCEED THAT. GUSTY NORTHWEST WINDS WILL ALSO
MATERIALIZE IN THE SOUTHERN GREAT BASIN BEHIND THE COLD FRONT.
IMPROVING CONDITIONS ARE EXPECTED TUESDAY AS A SHORTWAVE RIDGE
BUILDS IN AND TEMPERATURES WARM CLOSER TO SEASONAL NORMALS.
.LONG TERM...WEDNESDAY THROUGH SATURDAY.
THE PROGRESSIVE PATTERN CONTINUES WITH YET ANOTHER PACIFIC TROUGH
FORECAST TO DIVE ACROSS NORTHERN CALIFORNIA WEDNESDAY AND SPIN INTO
A CLOSED UPPER LOW OVER THE DESERT SOUTHWEST WEDNESDAY NIGHT AND
THURSDAY. THE MEDIUM RANGE MODELS ARE IN FAIRLY GOOD AGREEMENT WITH
THE TRACK AND TIMING OF THIS SYSTEM THROUGH THURSDAY AND CONFIDENCE
IS HIGH THAT COOL AND SHOWERY WEATHER WILL OCCUR AGAIN ACROSS THE
FORECAST AREA WEDNESDAY AFTERNOON THROUGH THURSDAY. THE SYSTEM WILL
HAVE LIMITED MOISTURE DUE TO THE INLAND TRACK AND PRECIPITATION
AMOUNTS DO NOT LOOK IMPRESSIVE. THE PROBABILITY OF ANY PARTICULAR
POINT SEEING MEASURABLE PRECIPITATION IS 30-40 PERCENT IN THE
VALLEYS/DESERTS AND 50-60 PERCENT IN THE MOUNTAINS. SNOW LEVELS WILL
GENERALLY BE AROUND 7000 FEET THOUGH MAY DIP TO AROUND 6000 FEET IN
THE SOUTHERN SIERRA WEDNESDAY NIGHT.
THE LOW CENTER IS FORECAST TO LIFT ACROSS THE FOUR CORNERS REGION
FRIDAY THOUGH SOME LINGERING MOISTURE AND INSTABILITY ON THE BACK
SIDE OF THE TROUGH MAY KEEP A CHANCE OF SHOWERS GOING OVER THE
MOUNTAINS AND ZONES NORTH AND EAST OF LAS VEGAS FRIDAY AND TO A
LESSER EXTENT SATURDAY. THE OPERATIONAL MEDIUM RANGE MODELS INDICATE
ANOTHER SHORTWAVE TROUGH WILL DROP OVER EASTERN WA/OR AND IDAHO
SATURDAY THEN SLIDE DOWN THE NEVADA/UTAH BORDER SATURDAY NIGHT AND
SUNDAY. THIS WOULD PRIMARILY LEAD TO GUSTY NORTH WINDS AND COOLER
TEMPERATURES SUNDAY AND ALSO THE POSSIBILITY OF SHOWERS OVER LINCOLN
AND MOHAVE COUNTIES. CONFIDENCE IN ANY DETAILS BUT WILL TREND TEMPS
AND WINDS TOWARD THIS SCENARIO.
&&
.AVIATION...FOR MCCARRAN...CLOUDS WILL RAPIDLY INCREASE PRIOR TO
SUNRISE WITH SHOWERS DEVELOPING IN THE VICINITY OF THE AIRFIELD
BETWEEN 12-15Z. A PERIOD OF LIGHT RAIN IS PROBABLE THROUGH THE
MORNING HOURS WITH CIGS IN THE 4-6K RANGE AND MOUNTAIN OBSCURATIONS
LIKELY. WINDS WILL CONTINUE TO FAVOR A SOUTH OR SOUTHWEST DIRECTION
GENERALLY IN THE 9-12 KNOT RANGE...THOUGH OCCASIONAL STRONGER PULSES
CAN BE EXPECTED ESPECIALLY PRIOR TO THE ARRIVAL OF SHOWER ACTIVITY.
PERIODIC GUSTS TO 25 KNOTS POSSIBLE DURING THOSE PERIODS. IMPROVING
CONDITIONS EXPECTED IN THE AFTERNOON WITH CIGS RISING CLOSER TO 10K
WHILE CLOUDS BECOME MORE SCATTERED BUT ISOLATED SHOWERS REMAIN
POSSIBLE. BREEZY SOUTHWEST WINDS WILL CONTINUE INTO THE AFTERNOON AS
WELL IN THE 12-18KT RANGE WITH GUSTS TO 25KTS.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...WIDESPREAD SHOWERS AND ISOLATED THUNDERSTORMS EXPECTED
TODAY MAINLY NORTH OF INTERSTATE 40. EXPECT REDUCED CIGS ESPECIALLY
IN THE MORNING HOURS AND MOUNTAIN OBSCURATIONS...WITH POCKETS OF
TURBULENCE. STRONG WINDS EXPECTED ALONG A BELT FROM THE WESTERN
MOJAVE DESERT EASTWARD TOWARDS THE COLORADO RIVER. SITES SUCH AS
KNXP AND KDAG CAN ANTICIPATE WESTERLY WIND GUSTS OVER 45KTS ALONG
WITH AREAS OF BLOWING AND SUSPENDED DUST.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION IS NOT
ANTICIPATED THIS WEEKEND. HOWEVER, SPOTTERS SHOULD REPORT ANY
SIGNIFICANT WEATHER ACCORDING TO STANDARD OPERATING PROCEDURES.
&&
$$
UPDATE...GORELOW
SHORT TERM/AVIATION...OUTLER
LONG TERM...ADAIR
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
400 PM CDT MON APR 25 2016
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 400 PM CDT MON APR 25 2016
OUR FOCUS THROUGH TUESDAY IS ON THE LINGERING LIGHT RAIN...AND IN
PARTS OF WESTERN ND THE POTENTIAL FOR LIGHT SNOW.
AS OF 20 UTC...A MID-LEVEL LOW BASED NEAR 700 MB IS SPINNING OVER
SOUTHEAST ND PER SATELLITE...RADAR...AND RAP ANALSYES. RAIN MOVING
WESTWARD THROUGH CENTRAL AND SOUTHWEST ND AT MID AFTERNOON IS TIED
TO THE FORCING ASSOCIATED WITH THIS FEATURE...AND BROAD MID-LEVEL
DEFORMATION THAT STRETCHES BACK INTO NORTHEAST MT. MODEL GUIDANCE
FROM 12 UTC SUGGESTS THE MID-LEVEL LOW WILL SLOWLY WASH OUT BY 12
UTC TUESDAY...BUT THE LINGERING DEFORMATION-AIDED FORCING WILL BE
ENOUGH TO SUSTAIN THE PRECIPITATION ACROSS WESTERN ND TONIGHT. THE
12 UTC GFS...NAM AND ECMWF ARE IN GOOD AGREEMENT WITH THAT...AS AS
THE MORE RECENT RAPID-REFRESH /RAP AND HRRR/ GUIDANCE. THE THERMAL
PROFILE MAY MARGINALLY SUPPORT SOME LIGHT SNOW ACROSS WESTERN ND
TONIGHT AND TUESDAY MORNING. THE 12 UTC NAM WAS MORE ROBUST IN ITS
ADVERTISEMENT OF QPF FALLING AS SNOW /BASED ON THE NCEP DOMINANT
PRECIPITATION-TYPE ALGORITHM APPLIED TO ITS MASS FIELDS/ THAN MOST
OTHER GUIDANCE...BUT EVEN THE MULTI-MODEL CONSENSUS WE UTILIZED TO
CONSTRUCT THE FORECAST YIELDED UP TO ABOUT AN INCH OF SNOW IN SOME
PARTS OF WESTERN ND BY TUESDAY MORNING.
OTHERWISE...ON THE LARGE SCALE...AFTERNOON MOISTURE CHANNEL /WATER
VAPOR/ IMAGES SHOW THE NEXT IN WHAT HAS BEEN A SERIES OF SHORTWAVE
TROUGHS/CLOSED UPPER-LEVEL LOWS DIGGING INTO THE FOUR CORNERS. THE
IMPACTS FROM THIS WAVE WILL MOSTLY HOLD OFF UNTIL TUESDAY NIGHT OR
WEDNESDAY...BUT IT WILL REINFORCE BROAD DIFFLUENT FLOW ALOFT OVER
THE AREA DURING THE DAY TUESDAY. THAT IS SUPPORTIVE OF A CONTINUED
CHANCE OF RAIN AND SNOW...ESPECIALLY WEST OF HIGHWAY 83. HIGHS ARE
FORECAST TO BE IN THE 40S F WITH EASTERLY FLOW AND CLOUD COVER.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 400 PM CDT MON APR 25 2016
ANOTHER WAVE OF PRECIPITATION IS EXPECTED WEDNESDAY AND WEDNESDAY
NIGHT...WITH YET ONE MORE CHANCE OF RAINFALL THIS WEEKEND.
THE 12 UTC MODEL GUIDANCE IS IN RELATIVE SYNC ADVERTISING A 500-MB
LOW MOVING ACROSS NEB ON WEDNESDAY...WITH DEEP EAST-SOUTHEAST FLOW
ALOFT OVER THE NORTHERN PLAINS TO ITS NORTH. THE CONSENSUS OF THAT
GUIDANCE TAKES A WELL-DEFINED BATCH OF PRECIPITATION NORTHWARD AND
INTO SOUTHERN AND WESTERN ND BY DAYTIME WEDNESDAY. TWO CHALLENGES
WITH THAT PRECIPITATION SHIELD WILL BE 1/ DETERMINING ITS PHASE IN
WESTERN AND PERHAPS SOUTH CENTRAL ND WHERE SOME WET SNOW MAY OCCUR
AND 2/ DECIDING HOW FAR NORTH IT WILL REACH. WHERE THE FIRST ISSUE
IS CONCERNED...MODEL GUIDANCE HAS CONSISTENTLY BEEN CALLING FOR AN
AREA OF SUB-FREEZING 850-MB TEMPERATURES DEVELOPING WEDNESDAY WITH
THE ONSET OF THE PRECIPITATION...WHICH IS LIKELY SUGGESTS WET BULB
COOLING WILL BE NECESSARY TO DRIVE TEMPERATURES LOW ENOUGH FOR ANY
SNOWFALL. THAT IS SOMEWHAT OF A LOW-CONFIDENCE ITEM...AND MOST OF
THE 12 UTC GUIDANCE PRECIPITATION-TYPE ALGORITHM OUTPUT BACKED OFF
ON SNOWFALL POTENTIAL. THUS...WE HELD WITH A MIX OF RAIN AND SNOW
IN THE FORECAST FOR NOW. FINALLY...NOTE THAT THE PRECIPITATION ON
WEDNESDAY APPEARS TO EMANATE IN THE MODELS OUT OF THE DEEP MOIST
CONVECTION THAT ERUPTS LATE TUESDAY IN THE CENTRAL PLAINS. THAT IS
A REASONABLE SOLUTION...BUT WHEN DEEP CONVECTION IS INVOLVED THERE
IS ALWAYS SOME INHERENT UNCERTAINTY IN DOWNSTREAM PRECIPITATION.
OTHERWISE...MEAN WESTERN UNITED STATES TROUGHING WILL PERSIST INTO
THE WEEKEND...WITH ANOTHER CHANCE OF RAINFALL SATURDAY AND SUNDAY.
THE 12 UTC ECMWF LIFTED THE WEEKEND SHORTWAVE A BIT FURTHER NORTH
THAN ITS PREVIOUS RUNS AND 12 UTC GFS AND GFS ENSEMBLE...WHICH IS
INDICATIVE OF SOME UNCERTAINTY AS TO WHETHER OR NOT THE STATE WILL
JUST BE GRAZED BY THAT WAVE OR NOT. TEMPERATURES WILL REMAIN COOL
WITH HIGHS MAINLY IN THE 40S AND 50S F DURING THE LONG TERM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 400 PM CDT MON APR 25 2016
OCCASIONAL IFR CONDITIONS WILL CONTINUE AT KDIK/KJMS THROUGH TODAY
IN RAIN...STRATUS AND FOG. SNOW OR SLEET MAY MIX IN WITH THE RAIN AT
TIMES ACROSS SOUTHERN TERMINALS OF KDIK/KBIS. KBIS HAS BEEN
SURROUNDED BY IFR/LIFR CONDITIONS ALL DAY...THROUGH THE TERMINAL
SHOULD REMAIN MVFR. CONDITIONS WILL HOLD IN THE LOW VFR/MVFR RANGE
AT KISN/KMOT TODAY. WIDESPREAD IFR CONDITIONS ARE EXPECTED TONIGHT
ACROSS THE AREA IN STRATUS AND/OR FOG.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CJS
LONG TERM...CJS
AVIATION...NH
AREA FORECAST DISCUSSION
NWS Tulsa OK
226 PM CDT MON APR 25 2016
.DISCUSSION...
A few of the latest short term model runs of the HRRR have
isolated thunderstorms developing near boundary across far north-
central Oklahoma this afternoon. It appears from latest mesoscale
analysis that cap will be strong enough to suppress any convective
development however this will continue to be monitored. Slight
chance that a few elevated thunderstorms could develop overnight
across far northeast oklahoma/northwest Arkansas in low level jet
axis, however coverage is expected to remain isolated.
Significant severe weather event expected across much of eastern
Oklahoma and northwest Arkansas starting as early as late Tuesday
afternoon and continuing into the overnight hours. Models have
trended a little faster with upper wave, including thunderstorm
initiation Tuesday afternoon. Dry line will set up near the I-35
corridor with SBCAPES in excess of 4000 J/KG developing across
a large portion of eastern Oklahoma as moisture rich gulf air
continues to surge north.
As upper level speed max shifts into the region by late afternoon,
thunderstorms will likely develop along dryline and push into
portions of northeast oklahoma by late afternoon and at the latest
early evening. Forecast point soundings during this time support the
potential for supercells with all modes of severe weather likely,
including the potential for a few strong tornadoes. The greatest
tornado threat will be late afternoon/early evening near peak
heating with any isolated supercells that initially develop/move
into northeast Oklahoma.
Severe thunderstorms will likely continue to increase in coverage
across eastern Oklahoma during the evening hours, spreading into
northwest Arkansas by late evening as wind fields continue to
increase. A tornado threat will likely continue with this activity
although may transition more to a damaging wind threat depending on
the overall thunderstorm coverage and other storm scale interactions.
Regardless, as mentioned earlier, a widespread significant severe
weather event is anticipated for much eastern Oklahoma and northwest
Arkansas. Primary severe threat will diminish late Tuesday
night/Wednesday morning as main convective line shifts east of the
region.
There is still a limited potential for a few isolated strong to
severe thunderstorms along dry line Wednesday afternoon/evening
across far E OK/NW AR as steep mid level lapse rates develop in
association with upper low to the north. Primary limiting factor
will be that forcing will become weaker as low level wind fields
begin to veer Wednesday afternoon.
Brief break in the weather expected on Thursday before another
strong upper wave moves out of the desert southwest Friday/Saturday.
Showers/thunderstorms will likely develop along/north of warm front
near the Red River late Thursday night in Friday. Multiple rounds
of severe weather/heavy rainfall will be possible through Saturday
as warm front lifts north. In addition to the severe threat,
flooding will likely become an issue where the heavier rainfall
occurs. Lingering precipitation chances will continue into early
next week as low level moisture persists with a few weak upper
level impulses possible.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 70 83 63 82 / 10 40 80 10
FSM 67 84 65 83 / 20 20 80 40
MLC 69 81 64 82 / 10 20 80 20
BVO 65 83 60 81 / 20 40 80 10
FYV 62 82 60 79 / 20 20 80 30
BYV 64 83 62 79 / 20 30 80 50
MKO 67 81 64 81 / 10 20 80 20
MIO 66 83 64 81 / 20 20 80 20
F10 68 82 63 82 / 10 30 80 10
HHW 67 82 65 82 / 10 20 80 30
&&
.TSA Watches/Warnings/Advisories...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...20
LONG TERM....12
AREA FORECAST DISCUSSION
NWS MEDFORD OR
918 AM PDT MON APR 25 2016
.DISCUSSION...THE FORECAST WAS UPDATED THIS MORNING TO INCREASE
NORTH TO NORTHWEST WINDS TODAY OVER EASTERN PORTIONS OF LAKE AND
MODOC COUNTIES. WIND SPEEDS WILL BE STRONGEST THERE WITH BREEZY
CONDITIONS ACROSS THE EAST SIDE. ALSO...A FROST ADVISORY FOR
TONIGHT WAS ISSUED FOR THE VALLEYS OF EASTERN CURRY...JOSEPHINE
AND JACKSON COUNTIES. THERE WERE LIKELY A FEW PATCHES OF FROST
IN OUT-LYING WEST SIDE VALLEYS EARLY THIS MORNING. TONIGHT WILL
BE THE COLDEST NIGHT OF THE WEEK WITH FREEZING TEMPERATURES LIKELY
IN NORTHERN CALIFORNIA AND SOUTH CENTRAL OREGON. CLOUDS WILL
DIMINISH TODAY INTO TONIGHT THOUGH LOW CLOUDS ARE LIKELY TO FORM
AGAIN IN THE UMPQUA VALLEY.
AFTER A BRIEF PERIOD OF RIDGING TONIGHT INTO TUESDAY...A FRONT IS
LIKELY TO BRING MAINLY WEST SIDE PRECIPITATION TUESDAY NIGHT THEN
LINGERING SHOWERS WEDNESDAY INTO WEDNESDAY NIGHT. HIGH PRESSURE
WILL BRING WARMING AND DRYING THURSDAY THEN A WEAK TROUGH WILL
BRUSH PAST TO THE NORTH ON FRIDAY NIGHT WITH A FEW LIGHT SHOWERS
POSSIBLE IN DOUGLAS COUNTY. HIGH PRESSURE LOOKS TO BUILD IN FOR
THE WEEKEND INTO MONDAY.
&&
.AVIATION...FOR THE 25/12Z TAF CYCLE...PLENTY OF LOW LEVEL MOISTURE
REMAINS THIS MORNING AND THIS HAS RESULTED IN IFR CIGS/VIS AT
ROSEBURG. EXPECT THESE CONDITIONS TO LAST FOR MOST OF THE MORNING,
ALTHOUGH THERE IS A CHANCE CIGS COULD IMPROVE TO MVFR AROUND 18Z.
ELSEWHERE EXPECT VFR CIGS TO PREDOMINATE, BUT MOUNTAINS ARE
EXPECTED TO BE AT LEAST PARTLY OBSCURED THIS MORNING. ALSO CIGS
COULD SEE-SAW BRIEFLY FROM VFR TO MVFR AT KLAMATH FALLS THIS
MORNING, BUT CONFIDENCE IS LOW, SO KEPT IT OUT OF THE TAF. STABLE
CONDITIONS WILL CONTINUE TONIGHT WITH A CHANCE FOR IFR CIGS TO
RETURN AT ROSEBURG. -PETRUCELLI
&&
.MARINE...UPDATED 300 AM PDT MON 25 APR 2016...MODELS CONTINUE TO
SHOW LOW END SMALL CRAFT FOR SEAS WITH A WEST DOMINATED SWELL
AFFECTING ALL THE THE MARINE WATERS THROUGH THIS EVENING. HIGH
PRESSURE WILL BUILD OFFSHORE TODAY AND NORTH WINDS ARE EXPECTED TO
INCREASE. THE RAP SHOWS SMALL CRAFT FOR WINDS EDGING CLOSER TOWARDS
THE COAST, SO HAVE ADJUSTED THE SMALL CRAFT FOR WINDS TO REFLECT
THIS THIS THINKING. HIGH PRESSURE WILL WEAKEN AND MOVE OVER THE
WATERS TONIGHT THROUGH TUESDAY. A WEAK FRONT WILL MOVE THROUGH THE
WATERS TUESDAY NIGHT...THEN OFFSHORE HIGH PRESSURE REBUILDS AGAIN
WEDNESDAY AFTERNOON. THE MODELS REMAIN IN FAIRLY GOOD AGREEMENT
SHOWING A THERMAL TROUGH DEVELOPING AND STRENGTHENING BY THE LATTER
PART OF THE WEEK. WINDS IN THE SOUTHERN WATERS COULD REACH HIGH END
SMALL CRAFT BY THURSDAY WITH GALES POSSIBLE OVER THE SOUTHERN
PORTIONS OF MARINE ZONES 356 AND 376. NOTE THAT DETAILS ON THIS
COULD CHANCE, SO WATCH FOR UPDATES ON THIS. -PETRUCELLI
&&
.PREV DISCUSSION... /ISSUED 452 AM PDT MON APR 25 2016/
THE CLOSED LOW PRESSURE HAS MOVED INTO NORTHERN CALIFORNIA THIS
MORNING. THE LOW IS EXPECTED TO CONTINUE TO MOVE SOUTHEAST INTO
NEVADA. ISOLATED SHOWERS CONTINUE FROM THE CASCADES WEST. SNOW
SHOWERS WILL CONTINUE OVER THE WARNERS THIS MORNING FROM MOISTURE
WRAPPED AROUND THE LOW BUT BY THIS AFTERNOON THE ATMOSPHERE IS
EXPECTED TO STABILIZE UNDER NW FLOW ALOFT.
WE ARE EXPECTING LESS CLOUD COVER TONIGHT THAN PREVIOUSLY THOUGHT
AND THE RADIATIONAL COOLING COULD BRING OVERNIGHT LOWS FOR SW
OREGON AND NORTHERN CALIFORNIA VALLEYS INTO THE LOWER TO MID 30S
AND FROST IS POSSIBLE OVERNIGHT. PLEASE TAKE NEEDED PRECAUTIONS TO
AVOID FROST DAMAGE.
NO PRECIPITATION IS IN THE FORECAST FOR INLAND AREAS TUESDAY AS A
RIDGE BUILDS INTO THE AREA.THE ONLY EXCEPTION IS IN OUR MARINE
ZONES WHERE THE NEXT FRONT COULD SPREAD LIGHT RAIN LATE IN THE
DAY. THE WARM FRONT IS EXPECTED TO SPREAD LIGHT RAIN INLAND
TUESDAY NIGHT. THE UPPER LEVEL SUPPORT FOR THIS NEXT SYSTEM DIVES
INTO NORTHERN CALIFORNIA AGAIN ON WEDNESDAY BUT THERE WILL STILL
BE ENOUGH MOISTURE AND INSTABILITY TO PRODUCE SHOWERS IN SOUTHERN
OREGON.
SHOWERS WILL LINGER ACROSS THE WARNER MOUNTAINS ON THURSDAY BUT
THE REST OF OUR FORECAST AREA IS EXPECTED TO BE DRY. /FB
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...FROST ADVISORY FROM 3 AM TO 9 AM PDT TUESDAY FOR ORZ024-026.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FROM 2 PM THIS
AFTERNOON TO 11 PM PDT THIS EVENING FOR PZZ356-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
EVENING FOR PZZ350-356-370-376.
$$
DW/MP/CC
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1241 PM CDT MON APR 25 2016
.AVIATION...
CLOUDS ARE RAPIDLY DISSIPATING AND ALL TERMINALS WILL BE VFR
SHORTLY. THESE CONDITIONS WILL CONTINUE THROUGH THE AFTERNOON.
LOW CLOUDS WILL DEVELOP THIS EVENING LOWER CIGS TO MVFR AND THEN
IFR OVERNIGHT. VFR WILL RETURN AROUND 17Z AT DRT AND RIGHT AT THE
END OF THE 24 HOUR PERIOD IN AUSTIN AND SAN ANTONIO...SO ONLY
INCLUDE IN AUS AND SAT TAFS. THERE IS A CHANCE FOR THUNDERSTORMS
TUESDAY AFTERNOON AND HAVE INCLUDED PROB30 GROUPS AT AUS AND SAT.
&&
.PREV DISCUSSION... /ISSUED 406 AM CDT MON APR 25 2016/
SHORT TERM (TODAY THROUGH TUESDAY)...
THE POSSIBILITY OF STRONG TO SEVERE THUNDERSTORMS WILL BE THE
MAIN HIGHLIGHT OF THIS FORECAST PERIOD LATE AFTERNOON TUESDAY
INTO EARLY WEDNESDAY MORNING. LARGE HAIL AND DAMAGING WINDS APPEAR
TO THE PRIMARY THREATS AT THIS TIME. PLEASE STAY TUNED FOR FURTHER
UPDATES AS TIMING AND EVOLUTION BECOME MORE CLEAR.
LOW-LVL MOISTURE IS STREAMING IN ON SOUTHEAST WINDS THIS MORNING
AND CREATING WIDESPREAD OVERCAST SKY CONDITIONS. CLOUDS WILL
SLOWLY DISSIPATE THROUGH THE LATE MORNING WITH MORE SUN EXPECTED
THIS AFTERNOON. WITH SOUTH TO SOUTHWEST 925-700MB WINDS,
TEMPERATURES WILL CLIMB ABOVE NORMAL INTO THE UPPER 80S TO LOW 90S
WITH SOME MID 90S POSSIBLE ACROSS THE RIO GRANDE. AS FURTHER
HEATING OCCURS THIS AFTERNOON, DEWPOINTS WILL MIX OUT INTO THE LOW
TO MID 60S WITH PWATS NEAR 1.4". LACK OF DEEPER MOISTURE AND A
MID TO UPPER LEVEL TRIGGER MAY NOT ALLOW FOR SHOWER OR STORM
GENERATION THIS AFTERNOON DESPITE THE NEAR 3000 J/KG SBCAPE. A
CAPPING INVERSION IN PLACE MAY JUST BE SLIGHTLY TOO STRONG FOR
THUNDERSTORM INITIATION ON PARCEL BUOYANCY ALONE. THE NEW SPC SSEO
DOES SUGGEST SOME ACTIVITY COULD BE POSSIBLE IN THE 7-10PM RANGE
WHILE HRRR AND TEXAS TECH WRF DO NOT AGREE. GLOBAL MODELS SHOW
HINTS OF VERY ISOLATED ACTIVITY. IF A STORM WAS ABLE TO BREAK
THROUGH THE CAP...IT COULD BECOME STRONG GIVEN THE STEEP LAPSE
RATES IN PLACE. WILL HAVE MENTION SUPER LOW END CHANCES WITH
SLIGHT CHANCE THUNDER WORDING FOR WEAKER CAPPING AREAS THIS
AFTERNOON. A QUIET OVERNIGHT INTO TUESDAY MORNING IS EXPECTED WITH
LOW CLOUDS BUILDING BACK INTO THE REGION.
H5 HEIGHT FALLS WILL BEGIN EARLY TUESDAY MORNING ACROSS THE BIG
BEND OF TEXAS THAT MAY HELP SPARK OFF A FEW SHOWERS OVER THE
EDWARDS PLATEAU. MOST OF THIS ACTIVITY SHOULD STAY NORTH OF THE
REGION THROUGH THE EARLY AFTERNOON. A POWERFUL WEATHER SYSTEM
WILL PIVOT ACROSS THE SOUTHERN PLAINS DURING THE AFTERNOON. THE
STRONGEST FORCING WILL REMAIN NORTH WHERE THE BULK OF SEVERE
STORMS ARE EXPECTED. FARTHER SOUTH - CAPPING WILL INITIALLY KEEP
SHOWER AND STORM COVERAGE AT BAY UNTIL THE LATE AFTERNOON HOURS.
BUFR SOUNDINGS INDICATE THE INVERSION WEAKENING BY 4-6PM AND
INCREASED COVERAGE COULD OCCUR DURING THIS TIME OVER THE HILL
COUNTRY TO POSSIBLY THE I35 CORRIDOR. CONTINUED STEEP LAPSE RATES
NEAR 8 C/KM AND 30-40 KT DEEP LAYER SHEAR SHOULD SUPPORT STRONG TO
SEVERE STORMS. THE SPC HAS EXPANDED THE SLIGHT RISK OF SEVERE
STORMS FARTHER SOUTH AND WEST TUESDAY AFTERNOON AND INTO THE
OVERNIGHT. LARGE HAIL AND STRAIGHT-LINE DAMAGING WINDS WILL BE
THE MOST LIKELY HAZARDS BUT A TORNADO CAN NOT BE RULED OUT. LOW-
LVL SHEAR DOES NOT LOOK TO BE OVERLY IMPRESSIVE BUT 0-3KM SHEAR
VECTOR ORIENTATION SHOULD SUPPORT SEMI-DISCRETE STORMS THAT COULD
ACT TO SUPPORT THE LOW-END TORNADO RISK. ADDITIONAL HEIGHT FALLS
THROUGH MIDNIGHT FROM A SECONDARY IMPULSE COULD HELP ORGANIZE THE
STORMS INTO A LINE AND SHIFT IT SOUTHEAST THROUGH WEDNESDAY
MORNING. OVERALL STRENGTH OF THE LINE SHOULD DECREASE BUT SOME
CONTINUED STRONG STORMS COULD BE POSSIBLE. POCKETS OF HEAVY RAIN
WILL ALSO BE POSSIBLE BUT OVERALL COVERAGE SHOULD BE LOW ENOUGH TO
PRECLUDE A FLASH FLOOD WATCH. THIS ACTIVITY A SHOULD HELP FORCE
THE DRYLINE BOUNDARY THROUGH MOST OF THE REGION WEDNESDAY WITH
DRYING AND CLEARING THROUGH THE DAY.
LONG TERM (WEDNESDAY THROUGH SUNDAY)...
A CONTINUED ACTIVE PATTERN WILL PERSIST LATE WEEK AND EARLY
WEEKEND WITH SOME POTENTIAL IMPACTS FROM HEAVY RAINFALL AND
ANOTHER POSSIBILITY OF STRONG TO SEVERE STORMS.
THE DRYLINE/BOUNDARY SHOULD BE ALONG TO JUST INLAND FROM THE COAST
ON WEDNESDAY WITH DRIER AIR IN PLACE OVER MUCH OF SOUTH-CENTRAL
TEXAS. HOWEVER, BY THURSDAY, THE BOUNDARY WILL SHIFT BACK WEST TO
THE RIO GRANDE AS A SURFACE LOW DEVELOPS NEAR THE BIG BEND WITH
ANOTHER NEGATIVE TILTED TROUGH SWINGING ACROSS THE SW CONUS. AN
IMPLIED IMPULSE AHEAD OF THE PARENT LOW IS DEPICTED IN THE GFS/GEM
AND THIS COULD HELP GENERATE SCATTERED SHOWERS AND THUNDERSTORMS
THURSDAY AFTERNOON. WILL NEED TO MONITOR IF THESE CAN BECOME
STRONG TO SEVERE.
FRIDAY INTO SATURDAY WILL FEATURE THE PARENT CUT-OFF LOW MOVING
OVER NORTH TEXAS INTO THE GREAT PLAINS WITH A STRONG DIFFLUENT
UPPER JET STRUCTURE OVER SOUTH TEXAS. PWATS IN THE 1.6-1.9" ARE
PROGGED TO BE IN PLACE AS DECENTLY AGREED UPON MODEL GUIDANCE
SUGGESTS STRONG SYNOPTIC VERTICAL MOTION IN PLACE. THIS SET-UP
COULD LEAD TO PERIODS OF HEAVY RAIN FRIDAY AFTERNOON INTO SATURDAY
ALONG WITH STRONG TO SEVERE HAZARDS. THIS TIMEFRAME WILL NEED TO
WATCHED CLOSELY THROUGH THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 71 86 66 87 65 / 10 30 60 10 10
AUSTIN BERGSTROM INTL AIRPORT 70 86 66 86 63 / 10 30 60 10 10
NEW BRAUNFELS MUNI AIRPORT 70 87 66 87 64 / 10 30 50 10 10
BURNET MUNI AIRPORT 68 85 61 85 62 / 10 30 70 10 -
DEL RIO INTL AIRPORT 70 93 62 90 63 / - 10 20 - 0
GEORGETOWN MUNI AIRPORT 70 85 64 86 63 / 10 30 70 10 -
HONDO MUNI AIRPORT 70 88 64 89 63 / 10 20 40 10 -
SAN MARCOS MUNI AIRPORT 70 86 66 86 64 / 10 30 50 10 10
LA GRANGE - FAYETTE REGIONAL 71 86 69 86 68 / 10 20 50 20 10
SAN ANTONIO INTL AIRPORT 71 86 67 87 65 / 10 30 50 10 -
STINSON MUNI AIRPORT 71 89 68 88 65 / 10 20 40 10 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...05
SYNOPTIC/GRIDS...RUNYEN
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
517 PM CDT MON APR 25 2016
.UPDATE...
SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 10 PM.
WHEN THUNDERSTORMS HIT THE LAKE BREEZE... WE ARE SEEING A BRIEF
UPTICK IN STORM STRENGTH/GROWTH. THIS IS DUE TO THE STORMS GETTING A
LITTLE EXTRA LIFT. THEY TEND TO DROP LARGER THAN PEA SIZE HAIL JUST
EAST OF THE LAKE BREEZE.
THE THUNDERSTORMS ARE PULSE-LIKE AND TYPICAL OF SINGLE CELL STORMS.
WE ARE SEEING VERY FEW STORMS THAT SHOW PERSISTENT MID LEVEL
ROTATION. MANY OF THE STORMS ARE DEVELOPING WHERE CAPE IS ONLY
AROUND 500 J/KG AND 0-6KM SHEAR IS 40 TO 50 KNOTS.
THERE IS STILL POTENTIAL FOR THUNDERSTORMS TO REACH SEVERE
CRITERIA... ESPECIALLY WITH HAIL. THE INSTABILITY WILL HANG AROUND
SOUTHEAST WI UNTIL ONE MORE FRONT MOVES THROUGH... PROBABLY CLEARING
SOUTHEAST WI BY 10 PM. WE DROPPED THE WATCH FOR DANE... COLUMBIA AND
GREEN COUNTIES SINCE THERE IS MORE DRY AIR IN THAT AREA. MESO MODELS
KEEP CONVECTION CONFINED MAINLY IN EASTERN WI.
&&
.PREV DISCUSSION... /ISSUED 337 PM CDT MON APR 25 2016/
LATE THIS AFTERNOON...
SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 10 PM.
CONVECTION DEVELOPED SLIGHTLY EARLIER THAN ANTICIPATED. THEY ARE
FOCUSING ALONG A SURFACE FRONT DEFINED BY A WIND DIRECTION CHANGE
FROM SOUTH TO SW WITHIN THE LEADING GRADIENT BETWEEN HIGHEST CAPE
AND LOWER CAPE. BULK SHEAR OF 40 TO 50 KNOTS IS SUFFICIENT FOR HAIL.
WE HAVE HAD SEVERAL REPORTS OF LESS THAN ONE INCH HAIL SO FAR.
THE OTHER AREA OF INTEREST IS TOWARD FOND DU LAC AND SHEBOYGAN WHERE
THE WARM FRONT IS MEETING UP WITH THE PERSISTENT COLD NORTHEAST FLOW
OFF LAKE MICHIGAN. THE FRONT WITH THE WIND SHIFT IS MEETING UP WITH
THESE TWO FRONTAL BOUNDARIES AND THUNDERSTORMS ARE CONTINUOUSLY
DEVELOPING. THERE IS HIGH 0-1KM SHEAR AROUND 20 KT IN THIS AREA
ALTHOUGH LOWER CAPE. THIS IS THE AREA THAT WILL NEED TO BE WATCHED
CLOSELY FOR A POSSIBLE TORNADO.
THERE SHOULD BE MORE CONVECTION DEVELOPING IN SOUTH CENTRAL WI WITH
ANOTHER WEAK FRONT/DRY LINE APPROACHING. CAPE WILL LIKELY BE HIGHER
WITH THIS NEXT ROUND IF IT DEVELOPS AND THERE IS A LARGER HAIL
THREAT. THESE ADDITIONAL THUNDERSTORMS ARE EXPECTED TO EVOLVE INTO
MORE OF A LINE LATER THIS AFTERNOON. THERE IS A LAKE BREEZE
INFLUENCE WHICH INCREASES THE 0-1KM SHEAR.
PER THE LATEST HRRR MODEL AND OTHER MESOSCALE MODELS...
THUNDERSTORMS SHOULD NOW BE OUT OF SOUTHEAST WI BY 7 PM OR 8 AT THE
LATEST.
TONIGHT AND TUESDAY...
A COLD FRONT WILL SLIDE SOUTHWESTWARD THROUGH SOUTHERN WI LATE
TONIGHT AND BRING LOW CLOUDS AND BRISK NORTH TO NORTHEAST WINDS.
THERE IS 2000 TO 3000 FEET THICK LAYER OF SATURATION WITH THE LOW
CLOUDS WHICH COULD BE SUFFICIENT FOR DRIZZLE THROUGH MID TUE
MORNING.
TUESDAY NIGHT...FORECAST CONFIDENCE IS HIGH.
A MID LEVEL SHORT WAVE RIDGE AXIS WILL DRIFT OFF TO THE
EAST...ALLOWING THE NEXT CIRCULATION TO BEGIN IMPINGING ON
SOUTHWEST WISCONSIN TOWARD SUNRISE ON WED. MOST OF THE NIGHT
SHOULD BE DRY...WITH A CHANCE SNEAKING INTO THE FAR SOUTHWEST
AFTER 4 AM.
WEDNESDAY THROUGH THURSDAY...FORECAST CONFIDENCE IS MEDIUM.
A DECENT BAND OF PRECIP SHOULD DEVELOP WITHIN A DEEP AND
PRONOUNCED TROUGH AXIS DRIFTING ACROSS THE UPPER MIDWEST. THE MID
LEVEL SYSTEM IS DISPLACED QUITE A BIT FARTHER NORTH COMPARED TO
THE SURFACE LOW WHICH WILL DRIFT ACROSS CNTRL AND SRN IL LATE WED
NIGHT AND THURSDAY. THE MAIN CHALLENGE WILL BE HOW MUCH THE DRY
EASTERLY LOW LEVEL FLOW WILL ERODE THE ADVANCING RAIN TO THE
NORTH. THE NAM IS THE MOST CONSERVATIVE WITH THE RAIN...KEEPING IT
OUT OF OUR NE FORECAST AREA...WHILE THE GFS/EC/GEM DO TAKE IT
THROUGH SHEBOYGAN AND FOND DU LAC BY WEDNESDAY NIGHT. THE MOISTURE
TRANSPORT AND SUPPORT DIMINISHES BY THURSDAY AFTERNOON...SO WE
SHOULD SEE MOST OF THE RAIN END BY LATE AFTERNOON OR EARLIER.
FRIDAY...FORECAST CONFIDENCE IS HIGH.
THIS LOOKS LIKE A DRY AND COOL DAY AS HIGH PRESSURE RETURNS...BUT
THE COOL EAST TO NORTHEAST FLOW DOMINATES.
SATURDAY AND SUNDAY...FORECAST CONFIDENCE IS MEDIUM.
ANOTHER SIMILAR MID LEVEL CIRCULATION LIFTS INTO THE AREA FOR THE
WEEKEND...BRINGING CHANCES OF SHOWERS. THE COOL EAST NORTHEAST
FLOW CONTINUES.
AVIATION/00Z TAFS/...
SEVERAL ROUNDS OF NORTH TO SOUTH ORIENTED LINES OF SCATTERED
THUNDERSTORMS ARE EXPECTED TO TRACK THROUGH SOUTHEAST WI LATE THIS
AFTERNOON INTO THE EARLY EVENING. KEEP AN EYE ON RADAR FOR TIMING OF
THUNDERSTORMS. CIGS AND VSBY RESTRICTIONS ARE ONLY EXPECTED WITHIN
THE STORMS. SOME STORMS COULD PRODUCE LARGE HAIL AND DAMAGING WINDS.
A COLD FRONT WILL SLIDE SOUTH THROUGH SOUTHERN WI LATE TONIGHT.
EXPECT BRISK NORTHERLY WINDS AND A LOW STRATUS DECK...BELOW 1000
FT...INTO SRN WI. LOW CONFIDENCE... BUT THERE COULD BE DRIZZLE WITH
THE LOW CLOUDS AND SOME ASSOCIATED MVFR FOG.
MARINE...
SCATTERED THUNDERSTORMS EXPECTED THIS AFTERNOON AND EARLY EVENING.
SOME COULD BE SEVERE WITH LARGE HAIL AND DAMAGING WINDS.
WINDS WILL SHIFT TO THE NORTHWEST TO NORTH LATER THIS EVENING AS LOW
PRESSURE PASSES BY. LOOK FOR THOSE WINDS TO TURN STRONG AND GUSTY
LATER TONIGHT...SHIFTING TO THE NORTHEAST BY TUE AFTN. WAVES WILL
BUILD TO 3 TO 5 FEET TUE AM. THE HIGHER WINDS AND WAVES WILL
CONTINUE THROUGH WED SOUTH OF NORTH POINT LIGHTHOUSE WHILE FALLING
BELOW SCA CRITERIA LATE TUE EVE NORTH OF NORTH POINT LIGHTHOUSE.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY FROM 7 AM TUESDAY TO 1 AM CDT WEDNESDAY FOR
LMZ645-646.
SMALL CRAFT ADVISORY FROM 4 AM TO 10 PM CDT TUESDAY FOR LMZ643-
644.
&&
$$
UPDATE...MRC
TONIGHT/TUESDAY AND AVIATION/MARINE...MRC
TUESDAY NIGHT THROUGH MONDAY...DAVIS
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
337 PM CDT MON APR 25 2016
.LATE THIS AFTERNOON...
SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 10 PM.
CONVECTION DEVELOPED SLIGHTLY EARLIER THAN ANTICIPATED. THEY ARE
FOCUSING ALONG A SURFACE FRONT DEFINED BY A WIND DIRECTION CHANGE
FROM SOUTH TO SW WITHIN THE LEADING GRADIENT BETWEEN HIGHEST CAPE
AND LOWER CAPE. BULK SHEAR OF 40 TO 50 KNOTS IS SUFFICIENT FOR HAIL.
WE HAVE HAD SEVERAL REPORTS OF LESS THAN ONE INCH HAIL SO FAR.
THE OTHER AREA OF INTEREST IS TOWARD FOND DU LAC AND SHEBOYGAN WHERE
THE WARM FRONT IS MEETING UP WITH THE PERSISTENT COLD NORTHEAST FLOW
OFF LAKE MICHIGAN. THE FRONT WITH THE WIND SHIFT IS MEETING UP WITH
THESE TWO FRONTAL BOUNDARIES AND THUNDERSTORMS ARE CONTINUOUSLY
DEVELOPING. THERE IS HIGH 0-1KM SHEAR AROUND 20 KT IN THIS AREA
ALTHOUGH LOWER CAPE. THIS IS THE AREA THAT WILL NEED TO BE WATCHED
CLOSELY FOR A POSSIBLE TORNADO.
THERE SHOULD BE MORE CONVECTION DEVELOPING IN SOUTH CENTRAL WI WITH
ANOTHER WEAK FRONT/DRY LINE APPROACHING. CAPE WILL LIKELY BE HIGHER
WITH THIS NEXT ROUND IF IT DEVELOPS AND THERE IS A LARGER HAIL
THREAT. THESE ADDITIONAL THUNDERSTORMS ARE EXPECTED TO EVOLVE INTO
MORE OF A LINE LATER THIS AFTERNOON. THERE IS A LAKE BREEZE
INFLUENCE WHICH INCREASES THE 0-1KM SHEAR.
PER THE LATEST HRRR MODEL AND OTHER MESOSCALE MODELS...
THUNDERSTORMS SHOULD NOW BE OUT OF SOUTHEAST WI BY 7 PM OR 8 AT THE
LATEST.
.TONIGHT AND TUESDAY...
A COLD FRONT WILL SLIDE SOUTHWESTWARD THROUGH SOUTHERN WI LATE
TONIGHT AND BRING LOW CLOUDS AND BRISK NORTH TO NORTHEAST WINDS.
THERE IS 2000 TO 3000 FEET THICK LAYER OF SATURATION WITH THE LOW
CLOUDS WHICH COULD BE SUFFICIENT FOR DRIZZLE THROUGH MID TUE
MORNING.
.TUESDAY NIGHT...FORECAST CONFIDENCE IS HIGH.
A MID LEVEL SHORT WAVE RIDGE AXIS WILL DRIFT OFF TO THE
EAST...ALLOWING THE NEXT CIRCULATION TO BEGIN IMPINGING ON
SOUTHWEST WISCONSIN TOWARD SUNRISE ON WED. MOST OF THE NIGHT
SHOULD BE DRY...WITH A CHANCE SNEAKING INTO THE FAR SOUTHWEST
AFTER 4 AM.
.WEDNESDAY THROUGH THURSDAY...FORECAST CONFIDENCE IS MEDIUM.
A DECENT BAND OF PRECIP SHOULD DEVELOP WITHIN A DEEP AND
PRONOUNCED TROUGH AXIS DRIFTING ACROSS THE UPPER MIDWEST. THE MID
LEVEL SYSTEM IS DISPLACED QUITE A BIT FARTHER NORTH COMPARED TO
THE SURFACE LOW WHICH WILL DRIFT ACROSS CNTRL AND SRN IL LATE WED
NIGHT AND THURSDAY. THE MAIN CHALLENGE WILL BE HOW MUCH THE DRY
EASTERLY LOW LEVEL FLOW WILL ERODE THE ADVANCING RAIN TO THE
NORTH. THE NAM IS THE MOST CONSERVATIVE WITH THE RAIN...KEEPING IT
OUT OF OUR NE FORECAST AREA...WHILE THE GFS/EC/GEM DO TAKE IT
THROUGH SHEBOYGAN AND FOND DU LAC BY WEDNESDAY NIGHT. THE MOISTURE
TRANSPORT AND SUPPORT DIMINISHES BY THURSDAY AFTERNOON...SO WE
SHOULD SEE MOST OF THE RAIN END BY LATE AFTERNOON OR EARLIER.
.FRIDAY...FORECAST CONFIDENCE IS HIGH.
THIS LOOKS LIKE A DRY AND COOL DAY AS HIGH PRESSURE RETURNS...BUT
THE COOL EAST TO NORTHEAST FLOW DOMINATES.
.SATURDAY AND SUNDAY...FORECAST CONFIDENCE IS MEDIUM.
ANOTHER SIMILAR MID LEVEL CIRCULATION LIFTS INTO THE AREA FOR THE
WEEKEND...BRINGING CHANCES OF SHOWERS. THE COOL EAST NORTHEAST
FLOW CONTINUES.
&&
.AVIATION/00Z TAFS/...
SEVERAL ROUNDS OF NORTH TO SOUTH ORIENTED LINES OF SCATTERED
THUNDERSTORMS ARE EXPECTED TO TRACK THROUGH SOUTHEAST WI LATE THIS
AFTERNOON INTO THE EARLY EVENING. KEEP AN EYE ON RADAR FOR TIMING OF
THUNDERSTORMS. CIGS AND VSBY RESTRICTIONS ARE ONLY EXPECTED WITHIN
THE STORMS. SOME STORMS COULD PRODUCE LARGE HAIL AND DAMAGING WINDS.
A COLD FRONT WILL SLIDE SOUTH THROUGH SOUTHERN WI LATE TONIGHT.
EXPECT BRISK NORTHERLY WINDS AND A LOW STRATUS DECK...BELOW 1000
FT...INTO SRN WI. LOW CONFIDENCE... BUT THERE COULD BE DRIZZLE WITH
THE LOW CLOUDS AND SOME ASSOCIATED MVFR FOG.
&&
.MARINE...
SCATTERED THUNDERSTORMS EXPECTED THIS AFTERNOON AND EARLY EVENING.
SOME COULD BE SEVERE WITH LARGE HAIL AND DAMAGING WINDS.
WINDS WILL SHIFT TO THE NORTHWEST TO NORTH LATER THIS EVENING AS LOW
PRESSURE PASSES BY. LOOK FOR THOSE WINDS TO TURN STRONG AND GUSTY
LATER TONIGHT...SHIFTING TO THE NORTHEAST BY TUE AFTN. WAVES WILL
BUILD TO 3 TO 5 FEET TUE AM. THE HIGHER WINDS AND WAVES WILL
CONTINUE THROUGH WED SOUTH OF NORTH POINT LIGHTHOUSE WHILE FALLING
BELOW SCA CRITERIA LATE TUE EVE NORTH OF NORTH POINT LIGHTHOUSE.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY FROM 7 AM TUESDAY TO 1 AM CDT WEDNESDAY FOR
LMZ645-646.
SMALL CRAFT ADVISORY FROM 4 AM TO 10 PM CDT TUESDAY FOR LMZ643-
644.
&&
$$
TONIGHT/TUESDAY AND AVIATION/MARINE...MRC
TUESDAY NIGHT THROUGH MONDAY...DAVIS