Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/26/16
AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
239 PM PDT SUN APR 24 2016
.SYNOPSIS...
Gusty northwest winds will continue over much of the area through
monday. Temperatures will fluctuate from day to day through
Tuesday. Low pressure approaching from the northwest will bring
cooler weather and possible showers Wednesday and Thursday.
warmer conditions to quickly follow Friday through the weekend.
&&
.SHORT TERM...(TDY-TUE)
The dry front is moving through Los Angeles County this
afternoon. Colder air behind the front will tap into the 100 KT
jet aloft and produce northwest winds tonight through Monday
night...with Monday bringing the strongest and most widespread
winds overall. Wind advisories cover much of the area...and even
those not under a wind advisory will see breezy conditions at
times. With the strongest winds around Point Conception and the
nam showing 55 KT at 850 MB...went ahead and issued a high wind
warning for Santa Rosa and San Miguel Islands for tonight. These
winds will also push winds up against the northern slopes later
tonight and some light showers are likely. Snow levels will lower
through the night and should settle down near 5000 feet. There is
a 10 percent chance that the snow levels come in low enough to
produce a light snow shower over the Tejon Pass/Grapevine
area...but it should not stick.
Temperatures have peaked early today...tipping Monday`s cooling
hand. While the sharpest cooling will be over interior areas...all
areas should be noticeably cooler.
While the winds should weaken below advisory thresholds quickly
monday night...they will shift and become north to northeasterly
by tuesday morning. This will combine with a ridge of high
pressure nosing in from the west to produce noticeable warming.
Temperatures should push back to above normal in most
locations...and return to similar numbers as today.
Energy from a large low pressure system currently south of the
Aleutian Islands will break off and form a new system that will
settle into eastern California Wednesday and Thursday. Small
variations in this track will have large ramifications with the
outcome teetering on cold, rain, and thunderstorms...or dry and
windy. The current projections split this difference...but the
spread in the ensembles show that this track is still anything but
settled and run-to-run variations should be expected. Spread out
the chances of rain in time to account for the range of potential
tracks...with rain possible anytime on wednesday and/or Thursday.
while the current projected track supports a slight chance of
Thunderstorms in the forecast...will wait for another day before
adding them.
.LONG TERM...(WED-SAT)
Fairly confident that the low will move out of the area to the
east as both the GFS and ECMWF continue to sing in harmony. A
large 585 DM ridge of high pressure will then push in from the
west and onshore flow will be weak. Temperatures look poised to
soar by the weekend...with temperatures generally in the 80s
likely...and some 90s are possible.
&&
.AVIATION...24/1800Z...
Mid/upper level trough of low pressure over the area will shift
east as a ridge of high pressure upstream approaches the area.
Upper level strong southwest winds will become strong west by 24/23z
and strong northwest after 25/12z while mid level light to
moderate west-northwest winds become moderate to strong northwest
after 25/04z. Decreasing mid/upper level moisture after 24/22z.
Mixed moderate onshore and northerly pressure gradient through
25/04z and after 25/19z otherwise moderate northerly gradient.
marine inversion was south and west of the area and will differ
little Monday morning.
Marine layer at LAX at 1700Z is none.
KLAX...Decreasing mid/upper level cloud field after 24/21z.
Moderate onshore surface winds between 25/03-25/13z and after
25/18z.
KBUR...Decreasing mid/upper level cloud field after 24/21z. low
level north winds likely after 25/13z.
virtually certain - 95-100%
very likely - 80-95%
likely - 60-80%
chance - 30-60%
very unlikely - 20% OR LESS
&&
.MARINE...24/200 pM...
Northwest winds will likely increase through tonight over the
entire area and a gale warning is in effect through Monday night.
Northwest winds will diminish Monday night and are expected to
increase Tuesday afternoon and it is likely small craft advisory
conditions with gale gusts will exist from Piedras Blancas to San
Clemente Island including the west portion of the Santa Barbara
Basin through Thursday. Otherwise swells from a distant storm will
continue to subside but seas will build locally and become very
steep through Monday. A storm force wind fetch developed in the
Southern Ocean and oriented 200-180 degrees to Ventura County
overnight and swells originating from the fetch will begin to
arrive next week Saturday and probably generate hazardous surf and
extra currents and surging along exposed south facing shores
Saturday through Monday.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...High Surf Advisory in effect until 5 PM PDT Tuesday For zones
34-35. (See LAXCFWLOX).
Wind Advisory in effect until 9 PM PDT this evening For zones
34>36. (See LAXNPWLOX).
Beach Hazards Statement in effect through late Monday night
For zones 39>41-87. (See LAXCFWLOX).
Wind Advisory in effect until 3 AM PDT Tuesday For zones
39-52>54-59. (See LAXNPWLOX).
Wind Advisory in effect from noon to 9 PM PDT Monday For
zones 40-41. (See LAXNPWLOX).
Wind Advisory in effect until 9 PM PDT Monday For zone 87. (See LAXNPWLOX).
High Wind Warning in effect until 6 AM PDT Monday For zone
549. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect until 3 PM PDT this afternoon
For zones 645-670. (See LAXMWWLOX).
Gale Warning in effect until 5 AM PDT Tuesday For zones
645-670-673-676. (See LAXMWWLOX).
Small Craft Advisory in effect until 8 PM PDT this evening
For zones 650-655. (See LAXMWWLOX).
Gale Warning in effect from 8 PM this evening to 9 PM PDT
Monday For zones 650-655. (See LAXMWWLOX).
&&
$$
PUBLIC...Kittell
AVIATION...30
MARINE...30
SYNOPSIS...Kittell
weather.gov/losangeles
Area Forecast Discussion
National Weather Service Reno NV
231 PM PDT SUN APR 24 2016
.SYNOPSIS...
Low pressure will move through western Nevada tonight and Monday.
Light snow is expected near the Oregon Border tonight while most
locations see a few showers and brisk northwest winds. After a
break Tuesday, unsettled weather returns for Wednesday and
Thursday. A warming trend with dry weather is looking more likely
for next weekend.
&&
.SHORT TERM...
Scattered showers have developed across Northeast California and
Western NV this afternoon and will continue into the evening. With
the cloud cover, instability has not been as great as anticipated,
but a few thunderstorms remain possible through sunset. Localized
rainfall amounts up to 1/3" are possible in the heaviest showers.
Snow levels are running around 6000 feet into this evening, but
will drop as the cold upper low moves in.
Overnight and into Monday, have made a few adjustments based on
latest trends and model forecasts. The main adjustments were to
increase the precip chances north of a Susanville-Lovelock line
and increase winds a bit more Monday afternoon. With the upper low
diving into Western NV tonight, the GFS, HRRR and EC all show an
area of deformation setting up from Austin, NV to Cedarville, CA.
QPF amounts are averaging 1/4" to 1/2" in this band. Snow levels
are expected to drop to near 4000-4500 feet. Issued a winter
weather advisory for light snow amounts near the Oregon Border
where it is more likely to stick to roads as they will be in the
cold air longer.
Monday morning that band dissipates as the upper low moves into
southern NV. The low is moving through a little faster and will
take the upper cold pool with it resulting in more stabilization.
Still expect some showers in the afternoon, but they are looking
more likely to be confined to areas south of highway 50. It still
looks quite cool, and a brisk NW wind of 15-25 mph with higher
gusts will make it feel colder. With these winds aligned with
Pyramid Lake, issued a Lake Wind Advisory there.
Monday night and Tuesday will see quiet weather under a short wave
ridge. Then the next upper low is expected to arrive Tuesday night
into Wednesday. This one will not be quite as cold, although it
will have some moisture. Forcing also does not look overly strong,
so at this point we are expecting showers again with a few
thunderstorms possible. Wallmann
.LONG TERM...Thursday through Sunday...
Active weather continues late next week as mean upper level
troughing remains fixed over the Western United States. Low
pressure that will move into the region Wednesday will slowly exit
into the Inter-Mountain West Friday night into Saturday. Snow
levels remain around 6000-7000 feet through Friday before rising
7000-8000 feet over the weekend. Kept mention of thunderstorms for
Thursday afternoon since sufficient instability remains.
Models have changed a little from previous runs for Saturday and
Sunday. Previously, deterministic runs were showing another low
dropping into the backside of the trough impacting Western Nevada
and the Sierra. Now, deterministic runs and ensembles are favoring
a more eastward track with low pressure pushing through Eastern
Nevada and Utah. As a result, have begun to back off of
precipitation chances over the weekend. Correspondingly, have
increased daily highs for the weekend as well with temperatures
approaching 70 degrees for Western Nevada Valleys. Boyd
&&
.AVIATION...
Low pressure will continue to impact the region this afternoon
into Monday at all terminals. Expect periods of IFR/MVFR in the
Sierra by Monday morning with periods of snow. MVFR conditions
will be possible for Sierra Front with snow levels dragging down
to around 4500 feet. It is possible that there could be periods of
IFR and light rain/snow mix at KRNO and KCXP Monday morning as
well. However, surface temperatures for Sierra Front terminals
will be too warm to allow for much/any snow to stick on the
tarmac.
Winds will increase with gusts generally up to 30 knots for
Sierra Front terminals while winds at KTVL/KTRK being lighter due
to precipitation influences. KMMH may see a few intermittent gusts
up to 40 knots Monday. Boyd/Hoon
&&
.REV Watches/Warnings/Advisories...
NV...Lake Wind Advisory from 6 AM to 8 PM PDT Monday for Pyramid Lake
in NVZ004.
Winter Weather Advisory from 8 PM this evening to 8 AM PDT
Monday NVZ005.
CA...Winter Weather Advisory from 8 PM this evening to 8 AM PDT
Monday CAZ070.
&&
$$
For more information from the National Weather Service visit...
http://weather.gov/reno
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
305 PM MDT SUN APR 24 2016
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 214 PM MDT SUN APR 24 2016
FOR TONIGHT...THE UPPER TROUGH OVER THE NEBRASKA PANHANDLE WILL
CONTINUE TO LIFT TO THE NORTHEAST. LINGERING WRAP AROUND MOISTURE
WILL DIMINISH OVER THE NORTHEAST PLAINS BY THIS EVENING. DOWNWARD
QG DESCENT/SUBSIDENCE WILL CONTINUE THROUGH THIS EVENING. NAM12
SPATIAL CROSS-SECTIONS SHOW THE MOISTURE WEST OF THE CONTINENTAL
DIVIDE DECREASING THIS EVENING SO LIGHT SNOW SHOULD COME TO AN END
AS WELL. GUSTY WEST/NORTHWEST WINDS WILL LINGER THROUGH THIS
AFTERNOON BUT WILL DECREASE AS WELL AFTER 00Z. LATE TONIGHT... AN
UPPER LEVEL RIDGE OF HIGH PRESSURE WILL MOVE OVER THE CWA. THE
RIDGE AXIS WILL SLIDE TO THE EAST BY 18Z MONDAY. AN INCREASING
SOUTHWESTERLY FLOW WILL OCCUR AHEAD OF THE NEXT PACIFIC SYSTEM
WHICH WILL DROP INTO THE GREAT BASIN REGION MONDAY AFTERNOON. IN
THE MOUNTAINS...MID LEVEL MOISTURE WILL INCREASE COUPLED WITH WEAK
QG ASCENT AND AFTERNOON INSTABILITY TO PRODUCE A MIX OF RAIN/SNOW
SHOWERS ALONG WITH A FEW TSTMS. ACROSS THE NORTHEAST
PLAINS...SOUTHEASTERLY SFC WINDS WILL INCREASE IN THE AFTN WHICH
SHOULD PRODUCE A DENVER CYCLONE. NAM12 FORECAST SOUNDINGS HAVE AN
INVERTED-V PROFILE WITH CAPES AROUND 500 J/KG. GUSTY OUTFLOW WINDS
WILL BE THE MAIN ISSUE AT LEAST THROUGH THE AFTERNOON,
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 214 PM MDT SUN APR 24 2016
...COOLER AND UNSETTLED WEATHER THROUGH NEXT WEEKEND...
SHOWERS AND THUNDERSTORMS SHOULD BECOME MORE NUMEROUS OVER THE
FORECAST AREA THROUGH MONDAY EVENING AS SYNOPTIC SCALE Q-G LIFT
INCREASES AHEAD OF UPPER LOW MOVING EAST THROUGH UTAH. THE MODELS
HAVE COME INTO GOOD AGREEMENT WITH THE UPPER LOW MOVING
EAST/NORTHEAST FROM THERE INTO WESTERN COLORADO LATE MONDAY NIGHT
AND THEN ACROSS ROUGHLY THE FORT COLLINS-CHEYENNE AREA BY TUESDAY
MORNING. HOWEVER...IT SHOULD BE NOTED THE STORM SYSTEM HAS YET TO
MOVE ONSHORE AND THESE TYPES OF LOWS CAN TYPICALLY DIG MORE THAN
ADVERTISED...SO WILL CONTINUE TO WATCH FOR A FARTHER SOUTH TRACK.
AS A RESULT...WILL KEEP POPS RELATIVELY HIGH THROUGH THIS PERIOD
DESPITE THE THREAT OF A DRY SLOT. EVEN IF THE STORM KICKS OUT A
BIT FARTHER TO THE NORTH COULD STILL SEE CONVECTIVE SHOWERS AND
STORMS CONTINUE THROUGH THE NIGHT INTO TUESDAY GIVEN THE
INSTABILITY AND POTENTIAL FOR WEAK UPSLOPE BEHIND A FRONTAL
SURGE. SNOW LEVEL WILL EVENTUALLY FALL THROUGH THE FOOTHILLS AND
WE COULD EVEN SEE A MIX OF RAIN/SNOW DOWN INTO THE I-25 CORRIDOR
BY TUESDAY NIGHT AS COLD AIR MOVES IN ON THE BACK SIDE OF THIS
LOW. AT THIS TIME...MOST OF THE ACCUMULATING SNOWFALL SHOULD OCCUR
ABOVE 8000-9000 FEET WHERE SEVERAL INCHES POSSIBLE THROUGH TUESDAY
NIGHT. IF THE STORM DOES DROP FARTHER SOUTH...THEN NORTHERN
FOOTHILLS WOULD HAVE A HIGHER CHANCE OF ACCUMULATING SNOWFALL AS
WELL.
BY WEDNESDAY...UPPER LEVEL RIDGE OCCURS BUT STILL SOME MOISTURE
AROUND TO KEEP A LOW THREAT OF SHOWERS IN THE FORECAST. MOST OF
THE PLAINS SHOULD BE TOO STABLE TO SUPPORT ANY PRECIP SO WILL KEEP
MOST OF THE POPS CONFINED TO THE MOUNTAINS.
THE NEXT STORM SYSTEM WILL THEN BEGIN TO AFFECT THE AREA BY
THURSDAY WITH INCREASING CHANCE OF SHOWERS AND THUNDERSTORMS. THE
LAST COUPLE MODEL RUNS AND ENSEMBLES KEEP THE TRACK OF THIS STORM
A BIT FURTHER SOUTH SO OVERALL PRECIPITATION AMOUNTS WOULD LIKELY
BE HIGHER...AND MOST OF THAT FALLING IN SNOW OVER THE HIGHER
FOOTHILLS AND MOUNTAINS. THAT STORM SYSTEM SHOULD KICK TO THE EAST
BY SATURDAY BUT ANOTHER DISTURBANCE IS ADVERTISED TO QUICKLY FILL
IN BEHIND BY SUNDAY. DAYTIME HIGHS APPEAR TO AVERAGE A GOOD 10
DEGREES BELOW NORMAL FOR THE LATTER HALF OF THIS WEEK THROUGH NEXT
WEEKEND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 214 PM MDT SUN APR 24 2016
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. NORTHWEST WINDS
EXPECTED TO CONTINUE UNTIL 00-01Z...THEN THE HRRR MDLS SHOWS A
WEAK NNELY PUSH EARLY THIS EVENING...WHICH THEN TRANSITION A
SOUTHERLY DRAINAGE BY LATE EVENING. TRENDED THE LAST SET OF TAFS
BASED ON THIS MDL. FOR MONDAY...SFC WINDS BECOME SELY IN THE LATE
MORNING/AFTN WHICH WILL INDUCE A DENVER CYCLONE. INVERTED-V
SOUNDINGS IN THE AFTERNOON...SO PRIMARY CONCERN WITH ANY
DEVELOPING STORM WILL BE GUSTY OUTFLOW WINDS...35-40 KTS. STILL
THINK CIGS WILL REMAIN HIGH ENOUGH TO AVOID ANY RESTRICTIONS IN
THE AFTERNOON.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...COOPER
LONG TERM...BARJENBRUCH
AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
935 AM MDT SUN APR 24 2016
.UPDATE...
ISSUED AT 922 AM MDT SUN APR 24 2016
GUSTY WINDS INCREASING ACROSS THE THE CWA THIS MORNING. RADAR
SHOWING SOME LIGHT SHOWERS ASSOCIATED WITH THE WRAP AROUND MSTR
DROPPING OUT OF WY AND SWINGING ACROSS NORTHERN WELD COUNTY THIS
MORNING. HAVE ADJUSTED TO POPS NORTH OF DENVER TO DROP THE PCPN A
LITTLE FURTHER SOUTH. RUC13 SPATIAL CROSS-SECTIONS SHOW STRONGEST
WINDS IN THE FOOTHILLS WILL BE IN THE 16-18Z PERIOD...WHERE SOME
GUSTS TO AROUND 70 MPH WILL BE POSSIBLE. MADE SOME MINOR
ADJUSTMENTS TO THE MAX TEMPERATURES AS WELL...LOWERED THEM BY A
COUPLE OF DEGREES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 410 AM MDT SUN APR 24 2016
AN UPPER LEVEL STORM SYSTEM IS OVER SERN WY THIS MORNING AND WILL
MOVE SLOWLY EAST INTO NC NEBRASKA/SCNTRL SOUTH DAKOTA BY THIS
EVENING. SOME MOISTURE WILL ROTATE AROUND THE UPPER LEVEL LOW AND
COMBINED WITH DECENT OROGRAPHICS WILL PRODUCE SNOW IN THE NRN MTNS
THRU THE AFTN. BEST CHC WILL BE ACROSS ZN 31 AND WRN PORTIONS OF ZN
33. SNOWFALL AMOUNTS WILL BE IN THE 2 TO 4 INCH RANGE.
MEANWHILE A DISTURBANCE OVER NCTRL CO EARLY THIS MORNING WILL MOVE
ACROSS NERN CO BY EARLY AFTN. THERE WILL BE SOME WDLY SCT HIGH
BASED SHOWERS WITH THIS FEATURE ESPECIALLY NR THE WY-NE BORDER AREA.
AS FOR WINDS AM STILL A LITTLE CONCERNED THAT THERE WILL BE A PERIOD
OF STRONGER WINDS OVER PORTIONS OF THE HIGHER FOOTHILLS AND MTN
AREAS FM MID MORNING THRU MID AFTN. THE NORMAL WINDY AREAS WILL
LIKELY SEE A FEW GUSTS FM 70 TO 80 MPH DURING THIS PERIOD BUT THE
QUESTION IS HOW WIDESPREAD WILL THEY BE. AT THIS POINT CONFIDENCE
IS NOT HIGH AS TO HOW WIDESPREAD THEY WILL BE SO WILL NOT ISSUE A
WARNING FOR NOW. ACROSS THE PLAINS WILL LIKELY SEE GUSTS TO 50 MPH
AT TIMES NEAR THE WY BORDER WITH UP TO 40 MPH ACROSS THE REST OF
THE PLAINS BY MIDDAY. AS FOR HIGHS THIS AFTN READINGS WILL BE IN
THE MID 60S TO AROUND 70 ACROSS NERN CO.
FOR TONIGHT DRIER AIR WILL SPREAD ACROSS THE NRN MTNS SO ONLY EXPECT
A SLIGHT CHC OF -SHSN THRU THE EVENING HOURS. ACROSS THE PLAINS IT
WILL BE DRY. WINDS WILL CONTINUE GUSTY EARLY THIS EVENING ACROSS
THE PLAINS AND HIGHER TERRAIN BUT SHOULD GRADUALLY DECREASE BY LATE
EVENING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 410 AM MDT SUN APR 24 2016
THERE IS UPPER RIDGING OVER THE CWA MONDAY. THE NEXT UPPER
TROUGH/CLOSED LOW GETS INTO COLORADO BY 06Z MONDAY NIGHT. THE
VARIOUS MODELS BRING THE CIRCULATION CENTER FROM THE NORTHWESTERN
COLORADO CORNER AT 18Z TUESDAY TO THE NORTHEASTERN CORNER OF
COLORADO BY 12Z WEDNESDAY MORNING. THE FLOW ALOFT IS SOUTHWESTERLY
MONDAY AND MONDAY NIGHT. IT IS DUE SOUTHERLY TUESDAY...THEN WEAK
TUESDAY NIGHT WITH THE UPPER LOW RIGHT OVER THE CWA. THERE IS
PRETTY DECENT UPWARD QG VERTICAL VELOCITY OVER THE CWA MONDAY
INTO WEDNESDAY MORNING. THE BOUNDARY LAYER FLOW IS PROGGED TO BE
SOUTHEASTERLY ON MONDAY...EVEN MORE EASTERLY MONDAY NIGHT. ON
TUESDAY A SURFACE CYCLONE IS DEVELOPING OVER SOUTHEASTERLY
COLORADO WITH UPSLOPE FOR THE PLAINS AND FOOTHILLS. MORE NORTH-
NORTHWESTERLY WINDS ARE PROGGED TUESDAY NIGHT. THERE IS SOME
MOISTURE AROUND MONDAY AND MONDAY NIGHT...MORE SO IN THE
MOUNTAINS. THE MOISTURE IS MORE WIDESPREAD AND DEEPER ON TUESDAY
WITH THE UPPER LOW AROUND. THERE IS SOME MINOR CAPE AROUND OVER
THE MOUNTAINS LATE DAY MONDAY. THE CAPE IS MORE WIDESPREAD LATE
DAY TUESDAY WITH SOME VALUES OVER 1000 J/KG OVER THE FAR NORTHEAST
CORNER. THE LAPSE RATES ARE PRETTY STEEP BOTH LATE DAY PERIODS OF
MONDAY AND TUESDAY. THE QPF FIELDS HAVE MINOR AMOUNTS OF
MEASURABLE PRECIPITATION FOR THE CWA LATE DAY MONDAY INTO TUESDAY
MORNING. THERE IS A BIT MORE NOTED FOR MOST AREAS TUESDAY
AFTERNOON AND NIGHT. FOR POPS...WILL MAINLY HAVE "CHANCE"S IN FROM
MONDAY AFTERNOON THROUGH TUESDAY NIGHT. WILL HAVE "LIKELY"S FOR
LATE DAY TUESDAY. FOR TEMPERATURES...MONDAY`S HIGHS ARE 1-3 C
WARMER THAN TODAY`S. TUESDAY`S HIGHS ARE 4-11 C COLDER THAN
MONDAY`S FOR THE LATER DAYS...WEDNESDAY THROUGH SATURDAY...MODELS
HAVE WEAK UPPER RIDGING FOR THE CWA WEDNESDAY INTO THURSDAY
MORNING...THEN SOUTH OR SOUTHWESTERLY FLOW ALOFT INTO FRIDAY
...WITH THE NEXT UPPER TROUGH/CLOSED LOW TO MOVE IN LATER THURSDAY
NIGHT THROUGH FRIDAY NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 922 AM MDT SUN APR 24 2016
VFR THRU MONDAY MORNING. STILL EXPECT STRONG WINDS TODAY WITH
SUBSIDENCE ACROSS THE AREA. SHOULD SEE DECENT MIXING OF STRONGER
FLOW ALOFT THRU THE AFTN HOURS. WINDS AT DIA WLY AT THIS TIME AND
SHOULD BE WEST-NORTHWEST BY 18Z. WILL SEE A FEW GUSTS TO 25 KTS
THRU 18Z WITH GUSTS FM 30-35 KTS AFTER 18Z. WINDS SHOULD SLOWLY
DECREASE BY 23Z INTO THE EARLY EVENING HOURS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...COOPER
SHORT TERM...RPK
LONG TERM...RJK
AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
418 AM MDT SUN APR 24 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 410 AM MDT SUN APR 24 2016
AN UPPER LEVEL STORM SYSTEM IS OVER SERN WY THIS MORNING AND WILL
MOVE SLOWLY EAST INTO NC NEBRASKA/SCNTRL SOUTH DAKOTA BY THIS
EVENING. SOME MOISTURE WILL ROTATE AROUND THE UPPER LEVEL LOW AND
COMBINED WITH DECENT OROGRAPHICS WILL PRODUCE SNOW IN THE NRN MTNS
THRU THE AFTN. BEST CHC WILL BE ACROSS ZN 31 AND WRN PORTIONS OF ZN
33. SNOWFALL AMOUNTS WILL BE IN THE 2 TO 4 INCH RANGE.
MEANWHILE A DISTURBANCE OVER NCTRL CO EARLY THIS MORNING WILL MOVE
ACROSS NERN CO BY EARLY AFTN. THERE WILL BE SOME WDLY SCT HIGH
BASED SHOWERS WITH THIS FEATURE ESPECIALLY NR THE WY-NE BORDER AREA.
AS FOR WINDS AM STILL A LITTLE CONCERNED THAT THERE WILL BE A PERIOD
OF STRONGER WINDS OVER PORTIONS OF THE HIGHER FOOTHILLS AND MTN
AREAS FM MID MORNING THRU MID AFTN. THE NORMAL WINDY AREAS WILL
LIKELY SEE A FEW GUSTS FM 70 TO 80 MPH DURING THIS PERIOD BUT THE
QUESTION IS HOW WIDESPREAD WILL THEY BE. AT THIS POINT CONFIDENCE
IS NOT HIGH AS TO HOW WIDESPREAD THEY WILL BE SO WILL NOT ISSUE A
WARNING FOR NOW. ACROSS THE PLAINS WILL LIKELY SEE GUSTS TO 50 MPH
AT TIMES NEAR THE WY BORDER WITH UP TO 40 MPH ACROSS THE REST OF
THE PLAINS BY MIDDAY. AS FOR HIGHS THIS AFTN READINGS WILL BE IN
THE MID 60S TO AROUND 70 ACROSS NERN CO.
FOR TONIGHT DRIER AIR WILL SPREAD ACROSS THE NRN MTNS SO ONLY EXPECT
A SLIGHT CHC OF -SHSN THRU THE EVENING HOURS. ACROSS THE PLAINS IT
WILL BE DRY. WINDS WILL CONTINUE GUSTY EARLY THIS EVENING ACROSS
THE PLAINS AND HIGHER TERRAIN BUT SHOULD GRADUALLY DECREASE BY LATE
EVENING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 410 AM MDT SUN APR 24 2016
THERE IS UPPER RIDGING OVER THE CWA MONDAY. THE NEXT UPPER
TROUGH/CLOSED LOW GETS INTO COLORADO BY 06Z MONDAY NIGHT. THE
VARIOUS MODELS BRING THE CIRCULATION CENTER FROM THE NORTHWESTERN
COLORADO CORNER AT 18Z TUESDAY TO THE NORTHEASTERN CORNER OF
COLORADO BY 12Z WEDNESDAY MORNING. THE FLOW ALOFT IS SOUTHWESTERLY
MONDAY AND MONDAY NIGHT. IT IS DUE SOUTHERLY TUESDAY...THEN WEAK
TUESDAY NIGHT WITH THE UPPER LOW RIGHT OVER THE CWA. THERE IS
PRETTY DECENT UPWARD QG VERTICAL VELOCITY OVER THE CWA MONDAY
INTO WEDNESDAY MORNING. THE BOUNDARY LAYER FLOW IS PROGGED TO BE
SOUTHEASTERLY ON MONDAY...EVEN MORE EASTERLY MONDAY NIGHT. ON
TUESDAY A SURFACE CYCLONE IS DEVELOPING OVER SOUTHEASTERLY
COLORADO WITH UPSLOPE FOR THE PLAINS AND FOOTHILLS. MORE NORTH-
NORTHWESTERLY WINDS ARE PROGGED TUESDAY NIGHT. THERE IS SOME
MOISTURE AROUND MONDAY AND MONDAY NIGHT...MORE SO IN THE
MOUNTAINS. THE MOISTURE IS MORE WIDESPREAD AND DEEPER ON TUESDAY
WITH THE UPPER LOW AROUND. THERE IS SOME MINOR CAPE AROUND OVER
THE MOUNTAINS LATE DAY MONDAY. THE CAPE IS MORE WIDESPREAD LATE
DAY TUESDAY WITH SOME VALUES OVER 1000 J/KG OVER THE FAR NORTHEAST
CORNER. THE LAPSE RATES ARE PRETTY STEEP BOTH LATE DAY PERIODS OF
MONDAY AND TUESDAY. THE QPF FIELDS HAVE MINOR AMOUNTS OF
MEASURABLE PRECIPITATION FOR THE CWA LATE DAY MONDAY INTO TUESDAY
MORNING. THERE IS A BIT MORE NOTED FOR MOST AREAS TUESDAY
AFTERNOON AND NIGHT. FOR POPS...WILL MAINLY HAVE "CHANCE"S IN FROM
MONDAY AFTERNOON THROUGH TUESDAY NIGHT. WILL HAVE "LIKELY"S FOR
LATE DAY TUESDAY. FOR TEMPERATURES...MONDAY`S HIGHS ARE 1-3 C
WARMER THAN TODAY`S. TUESDAY`S HIGHS ARE 4-11 C COLDER THAN
MONDAY`S FOR THE LATER DAYS...WEDNESDAY THROUGH SATURDAY...MODELS
HAVE WEAK UPPER RIDGING FOR THE CWA WEDNESDAY INTO THURSDAY
MORNING...THEN SOUTH OR SOUTHWESTERLY FLOW ALOFT INTO FRIDAY
...WITH THE NEXT UPPER TROUGH/CLOSED LOW TO MOVE IN LATER THURSDAY
NIGHT THROUGH FRIDAY NIGHT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 410 AM MDT SUN APR 24 2016
VFR TODAY THRU TONIGHT. MAIN PROBLEM TODAY WILL BE THE WINDS.
WITH SUBSIDENCE ACROSS THE AREA SHOULD SEE DECENT MIXING OF STRONGER
FLOW ALOFT LATE THIS MORNING THRU THE AFTN HOURS. WINDS AT DIA
EARLY THIS MORNING HAVE SWITCHED BACK TO MORE SSW HOWEVER THEY
SHOULD GRADUALLY BECOME MORE WLY BY 15Z AND THEN WNW BY 18Z. MAY
SEE A FEW GUSTS TO 25 MPH BETWEEN 15Z AND 18Z WITH GUSTS FM 30 TO 35
AFTER 18Z. WINDS SHOULD SLOWLY DECREASE BY 23Z INTO THE EARLY
EVENING HOURS. THE RAP HAS WINDS BECOMING LIGHT NLY BY 02Z WHILE
THE HRRR HAS MORE OF A WSW DIRECTION. WILL TREND TOWARDS A MORE
WSW COMPONENT WITH SSW WINDS BY 06Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RPK
LONG TERM...RJK
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS ALBANY NY
819 PM EDT MON APR 25 2016
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL MOVE ALONG A FRONT
PROVIDING STEADY RAINFALL TONIGHT INTO TOMORROW WITH CHILLY
TEMPERATURES. DRY WEATHER WILL RETURN FOR WEDNESDAY INTO
THURSDAY...BUT TEMPERATURES WILL REMAIN ON THE COOL SIDE FOR LATE
APRIL.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 724 PM...A STATIONARY FRONT WILL REMAIN DRAPED ACROSS THE
LOWER GREAT LAKES...OHIO VALLEY AND SOUTHERN TIER OF NEW YORK
EARLY THIS EVENING...AS A WAVE OF LOW PRESSURE STARTS TO HEAD
EAST FROM THE W-CNTRL GREAT LAKES REGION. LIGHT RAIN WILL GRADUALLY
OVERSPREAD THE AREA OVERNIGHT AS THERE IS PLENTY OF DRY AIR IN
PLACE ACROSS THE REGION AHEAD OF THIS SYSTEM. THE POPS NEEDED TO
BE SLOWED DOWN BASED ON THE LATEST 3-KM HRRR AND OBSERVATIONAL
TRENDS. THE STEADIER RAIN DOES NOT LOOK LIKE IT WILL ARRIVE UNTIL
06Z-12Z...OR JUST AFTER MIDNIGHT.
IT WILL BE A CHILLY NIGHT AS COLD AIR WILL CONTINUE TO MOVE SOUTH
FROM NORTHERN NY. EXPECT LOWS TONIGHT TO RANGE FROM THE LOWER 30S
NORTHWEST TO THE UPPER 40S SOUTHEAST. IT WILL BE COLD ENOUGH FOR
SNOW LATE TONIGHT ACROSS PORTIONS OF THE SOUTHERN ADIRONDACKS AND
THE HIGHEST TERRAIN OF THE SOUTHERN GREEN MOUNTAINS. ACCUMULATIONS
OF AN INCH OR SO ARE POSSIBLE ACROSS THESE AREAS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
ON TUESDAY SEVERAL WAVES OF LOW PRESSURE WILL BE MOVING EAST ALONG
THE FRONTAL BOUNDARY LINES UP FROM THE WESTERN SOUTHERN TIER OF
NEW YORK TO THE WESTERN GREAT LAKES. THE FRONTAL BOUNDARY WILL
GRADUALLY DROP SOUTHWARD DURING THE DAY ALLOWING COLD AIR TO
CONTINUE TO BLEED SOUTHWARD. IN FACT TEMPERATURES IN MANY AREAS
WILL ONLY RISE SEVERAL DEGREES FROM MORNING LOWS. SNOW WILL
CONTINUE TO FALL ACROSS THE HIGHER TERRAIN OF THE SOUTHERN
ADIRONDACKS AS WELL AS THE HIGHEST TERRAIN OF THE SOUTHERN GREEN
MOUNTAINS. EXPECT SNOWFALL AMOUNTS IN THESE AREAS TO TOTAL 1 TO 3
INCHES THROUGH TUESDAY MORNING. FURTHER SOUTH IT WILL BE RAINING
MUCH OF THE DAY. HIGHS ON TUESDAY ARE EXPECTED TO RANGE FROM THE
MID TO UPPER 30S NORTHWEST TO LOW TO MID 50S SOUTHEAST.
FOR TUESDAY NIGHT CONDITIONS WILL START TO DRY OUT AS A RIDGE OF HIGH
PRESSURE STARTS TO BUILD SOUTHEAST FROM NORTHERN CANADA. LOWS WILL
BE IN THE MID 20S TO UPPER 30S.
WEDNESDAY INTO THURSDAY THE RIDGE OF HIGH PRESSURE WILL CONTINUE
TO BUILD ACROSS THE REGION ALTHOUGH IT WILL CONTINUE TO BE RATHER
COOL. HIGHS ON WEDNESDAY WILL RANGE FROM THE UPPER 30S TO MID 409S
NORTHWEST TO THE LOWER 60S SOUTHEAST. LOWS WEDNESDAY NIGHT WILL BE
IN THE MID 20S TO MID 30S WITH HIGHS ON THURSDAY IN THE UPPER 40S
TO UPPER 50S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
DURING THE FIRST THIRD OF THE EXTENDED...A BROAD AREA OF WEAK LOW
PRESSURE WILL TRAVERSE FROM THE MID-MISSISSIPPI VALLEY EAST TO THE
DELMARVA REGION. THIS WILL KEEP ANY PRECIPITATION MAINLY SOUTH OF
THE CAPITAL REGION THURSDAY NIGHT.
FRIDAY WILL BECOME DRIER WITH INCREASING SUNSHINE AS A HIGH PRESSURE
RIDGE STRENGTHENS ACROSS SOUTHEASTERN CANADA AND RIDGES DOWN THE
EASTERN SEABOARD DURING THE WEEKEND. OF COURSE...THIS WILL MEAN A
DRY AND PLEASANT WEEKEND... ESPECIALLY SATURDAY WITH MORE SUN THAN
CLOUDS...AND SEASONABLE TEMPERATURES. THE HIGHS EACH DAY FROM
FRIDAY THROUGH SUNDAY WILL BE IN THE 50S AND 60S.
CLOUDS ROLL IN AHEAD OF THE NEXT SYSTEM LATE SUNDAY...WITH POSSIBLE
RAIN ARRIVING AS EARLY AS SUNDAY NIGHT. SOME SNOW MAY MIX IN ACROSS
THE NORTHWEST PORTION OF THE ADIRONDACKS. RAIN CHANCES WILL BE
GREATEST MONDAY WITH HIGHS MOSTLY IN THE 50S. BY THIS TIME THE
LOW PRESSURE AREA WILL BE OVER THE OHIO VALLEY.
OVERNIGHT LOW TEMPERATURES WILL START OUT IN THE UPPER 20S NORTH TO
LOWER 40S SOUTH THURSDAY AND FRIDAY NIGHTS...WITH A SLIGHT
MODERATING TREND PRODUCING LOWS BY SUNDAY NIGHT RANGING FROM THE MID
30S TO MID 40S.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
A STATIONARY FRONT REMAINS NEAR THE NY AND PA BORDER TONIGHT. LOW
PRESSURE OVER THE CENTRAL GREAT LAKES REGION WILL MOVE ALONG THE
BOUNDARY AND PROVIDE PERIODS OF RAIN OVERNIGHT THROUGH MOST OF
TUESDAY.
MID LEVEL CLOUDS WILL GRADUALLY LOWER TO A STRATUS DECK IN THE
3.5-6 KFT AGL RANGE PRIOR TO 06Z/TUE WITH LIGHT RAIN MOVING IN.
THE RAIN WILL TURN INTO A STEADIER AND MORE STRATIFORM RAINFALL
BTWN 06Z-12Z WITH CIGS AND VSBYS LOWERING TO MVFR/IFR LEVELS AT
KALB/KGFL/KPOU/KPSF. THERE IS A GOOD CHANCE OF IFR VSBYS/CIGS
LASTING AT ALL THE TAF SITES UNTIL 17Z-19Z. IT WILL BE A GRADUAL
IMPROVEMENT TO LOW MVFR CIGS IN THE DAMP AIR MASS.
THE WINDS WILL BE VARIABLE IN DIRECTION AND LIGHT AT 7 KTS OR LESS
TONIGHT. THE WINDS WILL BECOME N TO NE AT 4-8 KTS DURING THE LATE
MORNING INTO THE AFTERNOON.
OUTLOOK...
TUESDAY NIGHT TO SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
STEADY RAINFALL WILL ARRIVE FOR TONIGHT INTO TOMORROW WITH CHILLY
TEMPERATURES. DRY WEATHER WILL RETURN FOR WEDNESDAY INTO
THURSDAY...BUT TEMPERATURES WILL REMAIN ON THE COOL SIDE.
RELATIVE HUMIDITY VALUES WILL INCREASE TO 80 TO 100 PERCENT
TONIGHT...DROP TO 70 TO 85 PERCENT ON TUESDAY...RECOVER TO 70 TO
95 PERCENT TUESDAY NIGHT...AND DROP TO 25 TO 35 PERCENT ON
WEDNESDAY.
WINDS WILL BECOME NORTHEAST AROUND 5 MPH TONIGHT AND
TUESDAY...AND THEN BECOME NORTH TO NORTHWEST AT 5 TO 10 MPH
TUESDAY NIGHT AND WEDNESDAY.
&&
.HYDROLOGY...
RAIN WILL OVERSPREAD THE REGION OVERNIGHT AND CONTINUE THROUGH
MUCH OF TUESDAY...AS WAVES OF LOW PRESSURE MOVE ALONG A BOUNDARY
AS IT GRADUALLY MOVES SOUTHWARD ACROSS THE REGION. FORECAST
RAINFALL AMOUNTS ARE UNCERTAIN AT THIS TIME...ALTHOUGH GENERALLY
ONE HALF TO ONE INCH OF RAIN IS EXPECTED AT THIS TIME. WITH
ANTECEDENT DRY CONDITIONS IN PLACE...MOST OF THE RAIN WILL SOAK
INTO THE GROUND WITH LIMITED RUNOFF. AS A RESULT ONLY MINIMAL
RISES WILL OCCUR ON RIVERS AND STREAMS.
DRIER WEATHER RETURNS BY MIDWEEK AS ANOTHER HIGH PRESSURE SYSTEM
BUILDS INTO THE REGION.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...11/WASULA
NEAR TERM...11/WASULA
SHORT TERM...11
LONG TERM...ELH
AVIATION...WASULA
FIRE WEATHER...11
HYDROLOGY...11/NAS
AREA FORECAST DISCUSSION
NWS ALBANY NY
724 PM EDT MON APR 25 2016
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL MOVE ALONG A FRONT
PROVIDING STEADY RAINFALL TONIGHT INTO TOMORROW WITH CHILLY
TEMPERATURES. DRY WEATHER WILL RETURN FOR WEDNESDAY INTO
THURSDAY...BUT TEMPERATURES WILL REMAIN ON THE COOL SIDE FOR LATE
APRIL.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 724 PM...A STATIONARY FRONT WILL REMAIN DRAPED ACROSS THE
LOWER GREAT LAKES...OHIO VALLEY AND SOUTHERN TIER OF NEW YORK
EARLY THIS EVENING...AS A WAVE OF LOW PRESSURE STARTS TO HEAD
EAST FROM THE W-CNTRL GREAT LAKES REGION. LIGHT RAIN WILL GRADUALLY
OVERSPREAD THE AREA OVERNIGHT AS THERE IS PLENTY OF DRY AIR IN
PLACE ACROSS THE REGION AHEAD OF THIS SYSTEM. THE POPS NEEDED TO
BE SLOWED DOWN BASED ON THE LATEST 3-KM HRRR AND OBSERVATIONAL
TRENDS. THE STEADIER RAIN DOES NOT LOOK LIKE IT WILL ARRIVE UNTIL
06Z-12Z...OR JUST AFTER MIDNIGHT.
IT WILL BE A CHILLY NIGHT AS COLD AIR WILL CONTINUE TO MOVE SOUTH
FROM NORTHERN NY. EXPECT LOWS TONIGHT TO RANGE FROM THE LOWER 30S
NORTHWEST TO THE UPPER 40S SOUTHEAST. IT WILL BE COLD ENOUGH FOR
SNOW LATE TONIGHT ACROSS PORTIONS OF THE SOUTHERN ADIRONDACKS AND
THE HIGHEST TERRAIN OF THE SOUTHERN GREEN MOUNTAINS. ACCUMULATIONS
OF AN INCH OR SO ARE POSSIBLE ACROSS THESE AREAS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
ON TUESDAY SEVERAL WAVES OF LOW PRESSURE WILL BE MOVING EAST ALONG
THE FRONTAL BOUNDARY LINES UP FROM THE WESTERN SOUTHERN TIER OF
NEW YORK TO THE WESTERN GREAT LAKES. THE FRONTAL BOUNDARY WILL
GRADUALLY DROP SOUTHWARD DURING THE DAY ALLOWING COLD AIR TO
CONTINUE TO BLEED SOUTHWARD. IN FACT TEMPERATURES IN MANY AREAS
WILL ONLY RISE SEVERAL DEGREES FROM MORNING LOWS. SNOW WILL
CONTINUE TO FALL ACROSS THE HIGHER TERRAIN OF THE SOUTHERN
ADIRONDACKS AS WELL AS THE HIGHEST TERRAIN OF THE SOUTHERN GREEN
MOUNTAINS. EXPECT SNOWFALL AMOUNTS IN THESE AREAS TO TOTAL 1 TO 3
INCHES THROUGH TUESDAY MORNING. FURTHER SOUTH IT WILL BE RAINING
MUCH OF THE DAY. HIGHS ON TUESDAY ARE EXPECTED TO RANGE FROM THE
MID TO UPPER 30S NORTHWEST TO LOW TO MID 50S SOUTHEAST.
FOR TUESDAY NIGHT CONDITIONS WILL START TO DRY OUT AS A RIDGE OF HIGH
PRESSURE STARTS TO BUILD SOUTHEAST FROM NORTHERN CANADA. LOWS WILL
BE IN THE MID 20S TO UPPER 30S.
WEDNESDAY INTO THURSDAY THE RIDGE OF HIGH PRESSURE WILL CONTINUE
TO BUILD ACROSS THE REGION ALTHOUGH IT WILL CONTINUE TO BE RATHER
COOL. HIGHS ON WEDNESDAY WILL RANGE FROM THE UPPER 30S TO MID 409S
NORTHWEST TO THE LOWER 60S SOUTHEAST. LOWS WEDNESDAY NIGHT WILL BE
IN THE MID 20S TO MID 30S WITH HIGHS ON THURSDAY IN THE UPPER 40S
TO UPPER 50S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
DURING THE FIRST THIRD OF THE EXTENDED...A BROAD AREA OF WEAK LOW
PRESSURE WILL TRAVERSE FROM THE MID-MISSISSIPPI VALLEY EAST TO THE
DELMARVA REGION. THIS WILL KEEP ANY PRECIPITATION MAINLY SOUTH OF
THE CAPITAL REGION THURSDAY NIGHT.
FRIDAY WILL BECOME DRIER WITH INCREASING SUNSHINE AS A HIGH PRESSURE
RIDGE STRENGTHENS ACROSS SOUTHEASTERN CANADA AND RIDGES DOWN THE
EASTERN SEABOARD DURING THE WEEKEND. OF COURSE...THIS WILL MEAN A
DRY AND PLEASANT WEEKEND... ESPECIALLY SATURDAY WITH MORE SUN THAN
CLOUDS...AND SEASONABLE TEMPERATURES. THE HIGHS EACH DAY FROM
FRIDAY THROUGH SUNDAY WILL BE IN THE 50S AND 60S.
CLOUDS ROLL IN AHEAD OF THE NEXT SYSTEM LATE SUNDAY...WITH POSSIBLE
RAIN ARRIVING AS EARLY AS SUNDAY NIGHT. SOME SNOW MAY MIX IN ACROSS
THE NORTHWEST PORTION OF THE ADIRONDACKS. RAIN CHANCES WILL BE
GREATEST MONDAY WITH HIGHS MOSTLY IN THE 50S. BY THIS TIME THE
LOW PRESSURE AREA WILL BE OVER THE OHIO VALLEY.
OVERNIGHT LOW TEMPERATURES WILL START OUT IN THE UPPER 20S NORTH TO
LOWER 40S SOUTH THURSDAY AND FRIDAY NIGHTS...WITH A SLIGHT
MODERATING TREND PRODUCING LOWS BY SUNDAY NIGHT RANGING FROM THE MID
30S TO MID 40S.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
MID LEVEL CLOUDS WILL REMAIN IN PLACE FOR THE REMAINDER OF THE
AFTN AND INTO THE EVENING. IT SHOULD STAY DRY THROUGH THIS TIME
WITH CONTINUED VFR CONDITIONS. LIGHT N-NE WINDS WILL BE 5 KTS OR
LESS.
AN APPROACHING STORM SYSTEM WILL BRING SOME RAIN TO THE REGION
TONIGHT. ALTHOUGH THERE COULD BE SOME LIGHT RAIN BEGINNING LATE
THIS EVENING...THE BULK OF IT WON/T COME UNTIL AFTER MIDNIGHT.
FLYING CONDITIONS LOOK TO LOWER TO AT LEAST MVFR FOR BOTH VSBY AND
CIGS WITH STEADY LIGHT RAIN LATE TONIGHT. SOME PERIODS OF IFR
CONDITIONS CANNOT BE RULED OUT...BUT IT/S TOUGH TO SAY AT THIS
POINT AT WHAT TIME AND FOR HOW LONG IT WILL LAST...SO WILL NOT
INCLUDE IN THE TAF JUST YET. WINDS WILL GENERALLY BE FROM THE
NORTH AT 5-10 KTS.
STEADY RAIN WILL CONTINUE INTO THE MORNING HOURS ON TUESDAY...BUT
SHOULD START TO LIGHTEN UP AND TAPER OFF TOWARDS NOON OR EARLY
AFTERNOON TUESDAY. WITH LOTS OF LOW LEVEL MOISTURE TRAPPED BENEATH
AN INVERSION...MVFR CIGS WILL CONTINUE INTO THE AFTN DESPITE AN
IMPROVEMENT IN VSBY. WINDS WILL CONTINUE TO BE N-NE AT 5-10 KTS.
OUTLOOK...
TUESDAY NIGHT TO SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
STEADY RAINFALL WILL ARRIVE FOR TONIGHT INTO TOMORROW WITH CHILLY
TEMPERATURES. DRY WEATHER WILL RETURN FOR WEDNESDAY INTO
THURSDAY...BUT TEMPERATURES WILL REMAIN ON THE COOL SIDE.
RELATIVE HUMIDITY VALUES WILL INCREASE TO 80 TO 100 PERCENT
TONIGHT...DROP TO 70 TO 85 PERCENT ON TUESDAY...RECOVER TO 70 TO
95 PERCENT TUESDAY NIGHT...AND DROP TO 25 TO 35 PERCENT ON
WEDNESDAY.
WINDS WILL BECOME NORTHEAST AROUND 5 MPH TONIGHT AND
TUESDAY...AND THEN BECOME NORTH TO NORTHWEST AT 5 TO 10 MPH
TUESDAY NIGHT AND WEDNESDAY.
&&
.HYDROLOGY...
RAIN WILL OVERSPREAD THE REGION OVERNIGHT AND CONTINUE THROUGH
MUCH OF TUESDAY...AS WAVES OF LOW PRESSURE MOVE ALONG A BOUNDARY
AS IT GRADUALLY MOVES SOUTHWARD ACROSS THE REGION. FORECAST
RAINFALL AMOUNTS ARE UNCERTAIN AT THIS TIME...ALTHOUGH GENERALLY
ONE HALF TO ONE INCH OF RAIN IS EXPECTED AT THIS TIME. WITH
ANTECEDENT DRY CONDITIONS IN PLACE...MOST OF THE RAIN WILL SOAK
INTO THE GROUND WITH LIMITED RUNOFF. AS A RESULT ONLY MINIMAL
RISES WILL OCCUR ON RIVERS AND STREAMS.
DRIER WEATHER RETURNS BY MIDWEEK AS ANOTHER HIGH PRESSURE SYSTEM
BUILDS INTO THE REGION.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...11/WASULA
NEAR TERM...11/WASULA
SHORT TERM...11
LONG TERM...ELH
AVIATION...FRUGIS
FIRE WEATHER...11
HYDROLOGY...11/NAS
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
737 AM EDT SUN APR 24 2016
.AVIATION...AREAS OF FOG ARE BEING REPORTED REDUCING THE
VISIBILITY TO LIFR AT LAL/PGD. THIS FOG IS EXPECTED TO BURN OFF
PRETTY QUICK THIS MORNING SO WILL KEEP A TEMPO GROUP UNTIL
13Z...THEN BECOMING VFR FOR ALL TERMINALS. A BRIEF SHOWER WILL BE
POSSIBLE LATER TODAY AS THE SEA BREEZE FORMS UP AFTER 19Z SO WILL
COVER THIS WITH VCSH. NO OTHER AVIATION IMPACTS EXPECTED.
&&
.PREV DISCUSSION... /ISSUED 414 AM EDT SUN APR 24 2016/
SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOW RISING HEIGHTS IN
PROGRESS OVER THE FLORIDA PENINSULA EARLY THIS MORNING. THESE
HEIGHT RISES ARE OCCURRING ON THE BACKSIDE OF A DEPARTING LONGWAVE
TROUGH EXITING INTO THE WESTERN ATLANTIC. THE UPPER PATTERN IS
MUCH MORE ACTIVE OVER THE WESTERN AND CENTRAL CONUS AS A SERIES
OF UPPER DISTURBANCES CONTINUE TO ROTATE IN OFF THE PACIFIC AND
ACROSS THE CONTINENT. THE NORTHERN STREAM DISTURBANCES WILL NOT
HAVE MUCH IMPACT ON OUR WEATHER THROUGH THE FORECAST PERIOD AS
THEIR MAIN IMPACTS REMAIN WELL REMOVED FROM OUR LOCAL AREA. THERE
IS ONE WEAKER SOUTHERN STREAM IMPULSE CURRENTLY OVER NORTHERN
MEXICO THAT WILL BE MAKING SLOW PROGRESS ACROSS THE GULF OF MEXICO
THE NEXT 24-36 HOURS. WILL TALK MORE ABOUT THIS ENERGY AND ITS
POTENTIAL IMPACTS LOCALLY IN THE SHORT TERM DISCUSSION BELOW.
WATER VAPOR SHOWS LITTLE IN THE WAY OF MID/UPPER LEVEL MOISTURE
OVER THE STATE...ALLOWING FOR MOSTLY CLEAR SKIES. THE 24/00Z KTBW
SOUNDING PROFILE CONFIRMED THIS ANALYSIS...WITH A VERY DRY COLUMN
SAMPLED ABOVE 800MB...ALL THE WAY TO THE TROP.
AT THE SURFACE...HIGH PRESSURE CENTERED NEAR THE MID-ATLANTIC
COAST IS RIDGING SOUTHWARD AND BUILDING INTO OUR REGION. THIS
RIDGE WILL BE WITH US FOR THE NEXT SEVERAL DAYS AS IT SLOWLY
MIGRATES SOUTHEASTWARD. AREAS OF FOG HAVE DEVELOPED ACROSS THE
REGION SINCE MIDNIGHT. THIS IS NOT SURPRISING GIVEN THE RISING
HEIGHTS AND LARGE SCALE SUPPRESSION ONGOING OVER-TOP HIGHER LOW
LEVEL MOISTURE. THIS SETUP IS OFTEN FAVORABLE FOR GROUND FOG
DEVELOPMENT. OVERALL DO NOT ANTICIPATE WIDESPREAD DENSE
FOG...HOWEVER A FEW PATCHES OF SIGNIFICANT VISIBILITY REDUCTIONS
ARE POSSIBLE IN NORMALLY FOG PRONE AREAS THROUGH AROUND 13Z.
SHORT TERM (TODAY THROUGH MONDAY)...
AS MENTIONED ABOVE...HEIGHTS ARE RISING OVERHEAD THIS MORNING AS
MID/UPPER LEVEL RIDGING BUILDS OVER THE REGION. AT THE SAME
TIME...SURFACE HIGH PRESSURE IS RIDGING IN FROM THE NORTH/NE.
AFTER EARLY MORNING FOG PATCHES BURN OFF...WILL BE EXPECTING A
MOSTLY SUNNY MORNING WITH TEMPERATURES WARMING TOWARD 80 DEGREES
REGION-WIDE. THIS AFTERNOON...WINDS BEGIN TO SHIFT ONSHORE WITH
SEA-BREEZE DEVELOPMENT NEAR THE COAST...AND THIS WILL PROMOTE THE
DEVELOPMENT OF A FEW-SCT CUMULUS FIELD. GIVEN THE AMOUNT OF DRY
AIR ALOFT AND GENERALLY POOR MID-LEVEL LAPSE RATES...IT SEEMS
CONVECTION ALONG THE SEA- BREEZE WOULD HAVE A SIGNIFICANT
STRUGGLE. HOWEVER...VERY GOOD AGREEMENT AMONG THE CONVECTIVE
ALLOWING GUIDANCE THAT WE WILL SEE ISOLATED- SCT SHOWERS DEVELOP
LATE AFTERNOON/EARLY EVENING ALONG THE I-75 CORRIDOR. THE BEST
POTENTIAL FOR A LATE DAY SHOWER LOOKS TO BE FROM THE TAMPA BAY
AREA SOUTHWARD. SAYING SHOWER...ALTHOUGH AN ISOLATED THUNDERSTORM
CAN NOT BE RULED OUT. IN GENERAL GOING TO HAVE A HARD TIME
DEVELOPING UPDRAFTS DEEP ENOUGH FOR CHARGE SEPARATION AND
LIGHTNING...HOWEVER...A FEW STRONGER UPDRAFTS MAY BE ABLE TO
OVERCOME THE NEGATIVE DRY AIR ALOFT TO SUPPORT A THUNDERSTORM. ANY
SHOWER ACTIVITY (AND IT WILL BE SCT AT BEST) SHOULD HOLD OFF UNTIL
AFTER 20Z. HIGH TEMPERATURES THIS AFTERNOON WILL BE WELL UP INTO
THE 80S FOR MOST SPOTS AWAY FROM THE IMMEDIATE COAST. BEACHES WILL
BE A BIT COOLER WITH THE DEVELOPING ONSHORE FLOW...BUT SHOULD
STILL REACH THE LOWER 80S BEFORE THE SWITCH.
A FEW SHOWERS NEAR THE COAST IN THE EVENING DISSIPATE WITHIN A FEW
HOURS OF SUNSET AND RESULT IN A MOSTLY DRY OVERNIGHT THEREAFTER.
THE DRY CONDITIONS LEAD INTO MONDAY MORNING...WHEN A SIMILAR
FORECAST SCENARIO TO SUNDAY IS EXPECTED. THE ONLY DIFFERENCE WILL
BE THE APPROACH OF A WEAK SOUTHERN STREAM IMPULSE ACROSS THE GULF.
THIS IMPULSE WILL HELP IMPROVE/INCREASE THE MID-LEVEL LAPSE BY
1-2C/KM BY LATER MONDAY AND ALSO ADVECT SOME ADDED MOISTURE INTO
OUR COLUMN. THEREFORE...WOULD ANTICIPATE THE POTENTIAL FOR GREATER
COVERAGE OF SHOWERS OR ISOLATED STORMS AFTER 20Z. IT IS STILL
EARLY IN THE YEAR FOR SIGNIFICANT SEA-BREEZE CONVECTION...SO WILL
NOT GO MUCH ABOVE 30-40% POPS...HOWEVER...WILL NEED TO KEEP AN EYE
ON THE GUIDANCE SINCE THE ENERGY ALOFT WILL CERTAINLY LESSEN THE
CONVECTIVE INHIBITION.
MID/LONG TERM (MONDAY THROUGH NEXT SATURDAY)...
A LATE APRIL WEATHER PATTERN IS CERTAINLY IN PLACE ACROSS WEST
CENTRAL AND SW FLORIDA THIS WEEK AS TEMPERATURES WILL BE WARM WITH
LITTLE TO NO PRECIP EXPECTED. SURFACE HIGH PRESSURE WILL SHIFT OFF
THE EASTERN SEABOARD TO BEGIN THE WEEK AND REMAIN IN PLACE THROUGH
THE FORECAST PERIOD. THIS WILL KEEP OUR WEATHER FAIRLY QUIET
ALTHOUGH WARMER THAN NORMAL. WARM TEMPERATURES AND LIGHT STEERING
FLOW SHOULD ALLOW FOR DAILY SEABREEZES HOWEVER WITH PWAT VALUES IN
THE 1-1.25 INCH RANGE THERE IS NOT GOING TO BE A LOT OF MOISTURE
TO WORK WITH SO WILL KEEP RAIN CHANCES BELOW 20 PERCENT THOUGH THE
PERIOD. IT IS CERTAINLY POSSIBLE THAT MAYBE A STRAY SHALLOW SHOWER
MAY POP UP ALONG THE SEABREEZE BUT MOST OF THE AREA WILL REMAIN
DRY. AFTERNOON HIGH TEMPS ARE EXPECTED IN THE MID TO UPPER 80S FOR
MUCH OF THE WEEK WITH MAYBE A FEW INLAND LOCATIONS REACHING 90 BY
LATE WEEK...COOLER AT THE COAST WITH DAILY SEABREEZES.
AVIATION...
AREAS OF FOG HAVE ALREADY DEVELOPED EARLY THIS MORNING. A PERIOD
OF MVFR/IFR VISIBILITY MAY OCCUR AT ANY TIME THROUGH 13Z...
ESPECIALLY FOR KLAL AND KPGD. ONCE ANY EARLY MORNING FOG PATCHES
BURN OFF...VFR CONDITIONS WILL GENERALLY PREVAIL FOR ALL TERMINALS
THROUGH THE TAF PERIOD. AS THE SEA- BREEZE MOVES INLAND LATE THIS
AFTERNOON... THERE WILL BE A LOW CHANCE FOR A BRIEF SHOWER OR
STORM AT ANY OF THE TERMINALS...MAINLY AFTER 20Z.
MARINE...
HIGH PRESSURE OVER THE WESTERN ATLANTIC WILL RIDGE BACK WESTWARD
OVER THE EASTERN GULF OF MEXICO THROUGH THE MIDDLE OF THE WEEK.
WINDS AND SEAS WILL GENERALLY REMAIN BELOW HEADLINE CRITERIA
THROUGH THE FORECAST PERIOD. EXPECT WINDS TO SHIFT ONSHORE NEAR
THE COAST EACH DAY WITH SEABREEZE FORMATION. A FEW LATE AFTERNOON
OR EVENING THUNDERSTORMS ARE POSSIBLE NEAR THE COAST TODAY AND
AGAIN MONDAY. STORM COVERAGE WILL BE LOW...HOWEVER BOATERS SHOULD
KEEP AN EYE TO THE EAST LATE IN THE DAY AS ANY STORMS THAT DO
DEVELOP OVER LAND WILL TEND TO MIGRATE OFFSHORE.
FIRE WEATHER...
HIGH PRESSURE RIDGES OVER THE STATE THROUGH THE EARLY PORTION OF
THE WEEK. WINDS WILL GENERALLY REMAIN LIGHT...SHIFTING ONSHORE
NEAR THE COAST EACH AFTERNOON. MINIMUM RELATIVE HUMIDITY VALUES
BOTH SUNDAY AND MONDAY AFTERNOONS WILL BRIEFLY APPROACH 35
PERCENT...HOWEVER EXTENDED DURATIONS ARE NOT EXPECTED...AND WINDS
WILL REMAIN BELOW CRITICAL LEVELS...PREVENTING RED FLAG CONDITIONS.
THERE WILL BE A LOW CHANCE FOR A BRIEF LATE AFTERNOON OR EVENING
SHOWER THE NEXT SEVERAL AFTERNOON AS THE SEA-BREEZE PUSHES INLAND.
FOG POTENTIAL...AREAS OF FOG EARLY THIS MORNING WILL BURN OFF WITHIN
A FEW HOURS OF SUNRISE. NO SIGNIFICANT FOG CONCERNS ARE THEN
ANTICIPATED THROUGH MONDAY.
PRELIMINARY POINT TEMPS/POPS...
TPA 84 68 85 68 / 30 30 30 20
FMY 87 67 85 66 / 40 40 30 20
GIF 85 66 84 64 / 10 10 30 10
SRQ 80 67 81 66 / 30 30 20 10
BKV 85 63 84 61 / 20 20 30 10
SPG 84 69 83 69 / 40 40 20 10
TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 84 68 85 68 / 30 30 30 20
FMY 87 67 85 66 / 40 40 30 20
GIF 85 66 84 64 / 10 10 30 10
SRQ 80 67 81 66 / 30 30 20 10
BKV 85 63 84 61 / 20 20 30 10
SPG 84 69 83 69 / 40 40 20 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SHORT TERM/AVIATION/MARINE/FIRE WEATHER...74/WYNN
MID TERM/LONG TERM/DECISION SUPPORT...69/CLOSE
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
414 AM EDT SUN APR 24 2016
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOW RISING HEIGHTS IN
PROGRESS OVER THE FLORIDA PENINSULA EARLY THIS MORNING. THESE
HEIGHT RISES ARE OCCURRING ON THE BACKSIDE OF A DEPARTING LONGWAVE
TROUGH EXITING INTO THE WESTERN ATLANTIC. THE UPPER PATTERN IS
MUCH MORE ACTIVE OVER THE WESTERN AND CENTRAL CONUS AS A SERIES
OF UPPER DISTURBANCES CONTINUE TO ROTATE IN OFF THE PACIFIC AND
ACROSS THE CONTINENT. THE NORTHERN STREAM DISTURBANCES WILL NOT
HAVE MUCH IMPACT ON OUR WEATHER THROUGH THE FORECAST PERIOD AS
THEIR MAIN IMPACTS REMAIN WELL REMOVED FROM OUR LOCAL AREA. THERE
IS ONE WEAKER SOUTHERN STREAM IMPULSE CURRENTLY OVER NORTHERN
MEXICO THAT WILL BE MAKING SLOW PROGRESS ACROSS THE GULF OF MEXICO
THE NEXT 24-36 HOURS. WILL TALK MORE ABOUT THIS ENERGY AND ITS
POTENTIAL IMPACTS LOCALLY IN THE SHORT TERM DISCUSSION BELOW.
WATER VAPOR SHOWS LITTLE IN THE WAY OF MID/UPPER LEVEL MOISTURE
OVER THE STATE...ALLOWING FOR MOSTLY CLEAR SKIES. THE 24/00Z KTBW
SOUNDING PROFILE CONFIRMED THIS ANALYSIS...WITH A VERY DRY COLUMN
SAMPLED ABOVE 800MB...ALL THE WAY TO THE TROP.
AT THE SURFACE...HIGH PRESSURE CENTERED NEAR THE MID-ATLANTIC
COAST IS RIDGING SOUTHWARD AND BUILDING INTO OUR REGION. THIS
RIDGE WILL BE WITH US FOR THE NEXT SEVERAL DAYS AS IT SLOWLY
MIGRATES SOUTHEASTWARD. AREAS OF FOG HAVE DEVELOPED ACROSS THE
REGION SINCE MIDNIGHT. THIS IS NOT SURPRISING GIVEN THE RISING
HEIGHTS AND LARGE SCALE SUPPRESSION ONGOING OVER-TOP HIGHER LOW
LEVEL MOISTURE. THIS SETUP IS OFTEN FAVORABLE FOR GROUND FOG
DEVELOPMENT. OVERALL DO NOT ANTICIPATE WIDESPREAD DENSE
FOG...HOWEVER A FEW PATCHES OF SIGNIFICANT VISIBILITY REDUCTIONS
ARE POSSIBLE IN NORMALLY FOG PRONE AREAS THROUGH AROUND 13Z.
&&
.SHORT TERM (TODAY THROUGH MONDAY)...
AS MENTIONED ABOVE...HEIGHTS ARE RISING OVERHEAD THIS MORNING AS
MID/UPPER LEVEL RIDGING BUILDS OVER THE REGION. AT THE SAME
TIME...SURFACE HIGH PRESSURE IS RIDGING IN FROM THE NORTH/NE.
AFTER EARLY MORNING FOG PATCHES BURN OFF...WILL BE EXPECTING A
MOSTLY SUNNY MORNING WITH TEMPERATURES WARMING TOWARD 80 DEGREES
REGION-WIDE. THIS AFTERNOON...WINDS BEGIN TO SHIFT ONSHORE WITH
SEA-BREEZE DEVELOPMENT NEAR THE COAST...AND THIS WILL PROMOTE THE
DEVELOPMENT OF A FEW-SCT CUMULUS FIELD. GIVEN THE AMOUNT OF DRY
AIR ALOFT AND GENERALLY POOR MID-LEVEL LAPSE RATES...IT SEEMS
CONVECTION ALONG THE SEA- BREEZE WOULD HAVE A SIGNIFICANT
STRUGGLE. HOWEVER...VERY GOOD AGREEMENT AMONG THE CONVECTIVE
ALLOWING GUIDANCE THAT WE WILL SEE ISOLATED- SCT SHOWERS DEVELOP
LATE AFTERNOON/EARLY EVENING ALONG THE I-75 CORRIDOR. THE BEST
POTENTIAL FOR A LATE DAY SHOWER LOOKS TO BE FROM THE TAMPA BAY
AREA SOUTHWARD. SAYING SHOWER...ALTHOUGH AN ISOLATED THUNDERSTORM
CAN NOT BE RULED OUT. IN GENERAL GOING TO HAVE A HARD TIME
DEVELOPING UPDRAFTS DEEP ENOUGH FOR CHARGE SEPARATION AND
LIGHTNING...HOWEVER...A FEW STRONGER UPDRAFTS MAY BE ABLE TO
OVERCOME THE NEGATIVE DRY AIR ALOFT TO SUPPORT A THUNDERSTORM. ANY
SHOWER ACTIVITY (AND IT WILL BE SCT AT BEST) SHOULD HOLD OFF UNTIL
AFTER 20Z. HIGH TEMPERATURES THIS AFTERNOON WILL BE WELL UP INTO
THE 80S FOR MOST SPOTS AWAY FROM THE IMMEDIATE COAST. BEACHES WILL
BE A BIT COOLER WITH THE DEVELOPING ONSHORE FLOW...BUT SHOULD
STILL REACH THE LOWER 80S BEFORE THE SWITCH.
A FEW SHOWERS NEAR THE COAST IN THE EVENING DISSIPATE WITHIN A FEW
HOURS OF SUNSET AND RESULT IN A MOSTLY DRY OVERNIGHT THEREAFTER.
THE DRY CONDITIONS LEAD INTO MONDAY MORNING...WHEN A SIMILAR
FORECAST SCENARIO TO SUNDAY IS EXPECTED. THE ONLY DIFFERENCE WILL
BE THE APPROACH OF A WEAK SOUTHERN STREAM IMPULSE ACROSS THE GULF.
THIS IMPULSE WILL HELP IMPROVE/INCREASE THE MID-LEVEL LAPSE BY
1-2C/KM BY LATER MONDAY AND ALSO ADVECT SOME ADDED MOISTURE INTO
OUR COLUMN. THEREFORE...WOULD ANTICIPATE THE POTENTIAL FOR GREATER
COVERAGE OF SHOWERS OR ISOLATED STORMS AFTER 20Z. IT IS STILL
EARLY IN THE YEAR FOR SIGNIFICANT SEA-BREEZE CONVECTION...SO WILL
NOT GO MUCH ABOVE 30-40% POPS...HOWEVER...WILL NEED TO KEEP AN EYE
ON THE GUIDANCE SINCE THE ENERGY ALOFT WILL CERTAINLY LESSEN THE
CONVECTIVE INHIBITION.
&&
.MID/LONG TERM (MONDAY THROUGH NEXT SATURDAY)...
A LATE APRIL WEATHER PATTERN IS CERTAINLY IN PLACE ACROSS WEST
CENTRAL AND SW FLORIDA THIS WEEK AS TEMPERATURES WILL BE WARM WITH
LITTLE TO NO PRECIP EXPECTED. SURFACE HIGH PRESSURE WILL SHIFT OFF
THE EASTERN SEABOARD TO BEGIN THE WEEK AND REMAIN IN PLACE THROUGH
THE FORECAST PERIOD. THIS WILL KEEP OUR WEATHER FAIRLY QUIET
ALTHOUGH WARMER THAN NORMAL. WARM TEMPERATURES AND LIGHT STEERING
FLOW SHOULD ALLOW FOR DAILY SEABREEZES HOWEVER WITH PWAT VALUES IN
THE 1-1.25 INCH RANGE THERE IS NOT GOING TO BE A LOT OF MOISTURE
TO WORK WITH SO WILL KEEP RAIN CHANCES BELOW 20 PERCENT THOUGH THE
PERIOD. IT IS CERTAINLY POSSIBLE THAT MAYBE A STRAY SHALLOW SHOWER
MAY POP UP ALONG THE SEABREEZE BUT MOST OF THE AREA WILL REMAIN
DRY. AFTERNOON HIGH TEMPS ARE EXPECTED IN THE MID TO UPPER 80S FOR
MUCH OF THE WEEK WITH MAYBE A FEW INLAND LOCATIONS REACHING 90 BY
LATE WEEK...COOLER AT THE COAST WITH DAILY SEABREEZES.
&&
.AVIATION...
AREAS OF FOG HAVE ALREADY DEVELOPED EARLY THIS MORNING. A PERIOD
OF MVFR/IFR VISIBILITY MAY OCCUR AT ANY TIME THROUGH 13Z...
ESPECIALLY FOR KLAL AND KPGD. ONCE ANY EARLY MORNING FOG PATCHES
BURN OFF...VFR CONDITIONS WILL GENERALLY PREVAIL FOR ALL TERMINALS
THROUGH THE TAF PERIOD. AS THE SEA- BREEZE MOVES INLAND LATE THIS
AFTERNOON... THERE WILL BE A LOW CHANCE FOR A BRIEF SHOWER OR
STORM AT ANY OF THE TERMINALS...MAINLY AFTER 20Z.
&&
.MARINE...
HIGH PRESSURE OVER THE WESTERN ATLANTIC WILL RIDGE BACK WESTWARD
OVER THE EASTERN GULF OF MEXICO THROUGH THE MIDDLE OF THE WEEK.
WINDS AND SEAS WILL GENERALLY REMAIN BELOW HEADLINE CRITERIA
THROUGH THE FORECAST PERIOD. EXPECT WINDS TO SHIFT ONSHORE NEAR
THE COAST EACH DAY WITH SEABREEZE FORMATION. A FEW LATE AFTERNOON
OR EVENING THUNDERSTORMS ARE POSSIBLE NEAR THE COAST TODAY AND
AGAIN MONDAY. STORM COVERAGE WILL BE LOW...HOWEVER BOATERS SHOULD
KEEP AN EYE TO THE EAST LATE IN THE DAY AS ANY STORMS THAT DO
DEVELOP OVER LAND WILL TEND TO MIGRATE OFFSHORE.
&&
.FIRE WEATHER...
HIGH PRESSURE RIDGES OVER THE STATE THROUGH THE EARLY PORTION OF
THE WEEK. WINDS WILL GENERALLY REMAIN LIGHT...SHIFTING ONSHORE
NEAR THE COAST EACH AFTERNOON. MINIMUM RELATIVE HUMIDITY VALUES
BOTH SUNDAY AND MONDAY AFTERNOONS WILL BRIEFLY APPROACH 35
PERCENT...HOWEVER EXTENDED DURATIONS ARE NOT EXPECTED...AND WINDS
WILL REMAIN BELOW CRITICAL LEVELS...PREVENTING RED FLAG CONDITIONS.
THERE WILL BE A LOW CHANCE FOR A BRIEF LATE AFTERNOON OR EVENING
SHOWER THE NEXT SEVERAL AFTERNOON AS THE SEA-BREEZE PUSHES INLAND.
FOG POTENTIAL...AREAS OF FOG EARLY THIS MORNING WILL BURN OFF WITHIN
A FEW HOURS OF SUNRISE. NO SIGNIFICANT FOG CONCERNS ARE THEN
ANTICIPATED THROUGH MONDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 84 68 85 68 / 30 30 30 20
FMY 87 67 85 66 / 40 40 30 20
GIF 85 66 84 64 / 10 10 30 10
SRQ 80 67 81 66 / 30 30 20 10
BKV 85 63 84 61 / 20 20 30 10
SPG 84 69 83 69 / 40 40 20 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
MID TERM/LONG TERM/DECISION SUPPORT...MCKAUGHAN
Area Forecast Discussion
National Weather Service Lincoln IL
922 PM CDT MON APR 25 2016
.UPDATE...
Issued at 922 PM CDT Mon Apr 25 2016
Boundary is finally moving through the CWA this evening. Will need
to update pop/wx grids to account for current situation and
trends. Based on radar, isolated showers and thunderstorms will
continue to move through the CWA, mainly east of I-55. Boundary is
hard to see in the observations but it can be seen on radar just
passing the NWS office and is just east of I-55. This movement
will continue through the night, which means the showers could as
well. Other updates will be needed to account for the scattered
clouds in the west behind the boundary. Update forthcoming.
&&
.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 00Z TAFS through 00Z Tuesday evening)
Issued at 633 PM CDT Mon Apr 25 2016
VFR conditions will prevail at all TAF sites next 24hrs. Clouds
are high based around 7kft and am expecting sct-bkn clouds through
the evening. HRRR still shows some pcpn developing this evening
and moving across central IL, but think it will be near
SPI/DEC only. So will only have VCSH at these two sites and not
add til pcpn begins to showup on radar. Based on satellite loop,
must be some sort of CAP keeping storms from getting out of had.
Overnight once the frontal boundary pushes past the sites, skies
will become scattered. Boundary should push far enough south that
pcpn is not expected at any of the sites tomorrow. However, lower
clouds around 3.5kft will become broken at all sites. Winds will
be southerly, but then become southwest overnight and then
westerly tomorrow or variable with the front passing through late
tonight.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Auten
SHORT TERM...Geelhart
LONG TERM...BAK
AVIATION...Auten
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
646 PM CDT MON APR 25 2016
.MESOSCALE DISCUSSION...404 PM CDT
RAPID SCAN GOES IMAGERY INDICATES SOME STEADY VERTICAL GROWTH TO
THE CUMULUS LAYER OVER WINNEBAGO/BOONE COUNTIES. IN ADDITION THERE
HAS BEEN SOME EMBEDDED LIGHTNING WITHIN THE SHOWERS...BUT WITH THE
INCREASING EFFECTIVE SHEAR IN THE LOWER LEVELS AND STEEPENING
LAPSE RATES...EXPECT INTENSITY AND GROWTH TO TAKE PLACE WITHIN THE
NEXT HOUR OR BY 22Z. WINDS WITHIN THE 900-800MB LAYER ARE BECOMING
MORE CONVERGENT...WHICH COUPLED WITH THE DRIER AIR ARRIVING FROM
THE WEST AND THE WELL MIXED LOWER LEVELS HAS AIDED IN DCAPE VALUES
NEARING 1000J/KG ACROSS NORTHERN IL. ANY ROBUST/TALLER STORMS
WOULD LIKELY INTRODUCE A POTENTIAL FOR DAMAGING WINDS...COUPLED
WITH LARGE HAIL.
SEVERE THREAT IS LIKELY TO CONTINUE ACROSS FAR NORTHEAST IL
THROUGH APPROXIMATELY 00Z...THEN STORM MOTION SHOULD START TURNING
SOUTHEAST TOWARDS NORTHWEST INDIANA THROUGH 2Z.
BEACHLER
&&
.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 00Z TAFS...
MAIN AVIATION CONCERNS ARE ONGOING LOW COVERAGE TSRA/SHRA EARLY
THIS EVENING...THEN POTENTIAL FOR IFR/MVFR CIGS TUESDAY MORNING AS
WINDS TURN OFF LAKE MICHIGAN.
SURFACE LOW PRESSURE WAS OVER CENTRAL WI EARLY THIS EVENING...WITH
A COLD FRONT TRAILING SOUTHWEST ACROSS EASTERN IOWA. COMBINATION
OF MID-LEVEL DISTURBANCE MOVING THROUGH ALOFT AND WARM/MOIST
UNSTABLE AIR AHEAD OF THE FRONT HAS ALLOWED DEVELOPMENT OF
ISOLATED TSRA OVER NORTHERN/NORTHEAST IL...THOUGH SHALLOW NATURE
OF MOIST LAYER AND WEAK CONVERGENCE WITH WINDS ALREADY
SOUTHWESTERLY AHEAD OF THE FRONT WERE LIMITING COVERAGE. POTENTIAL
FOR ISOLATED TSRA/SHRA WILL LINGER THROUGH EARLY EVENING BEFORE
DECREASE IN INSTABILITY WITH SUNSET.
WINDS WILL SHIFT TO THE WEST-NORTHWEST LATE THIS EVENING AS THE
FRONT MOVES THROUGH...WITH WINDS EVENTUALLY VEERING TO NORTHEAST
DURING THE PRE-DAWN HOURS OF TUESDAY MORNING. COOL/MOIST MARINE
LAYER LOOKS TO SUPPORT LOW CIGS WITH IFR LIKELY EARLY...EVENTUALLY
RISING TO MID-HIGH MVFR RANGE LATER IN THE DAY.
RATZER
&&
.MARINE...
255 PM CDT
A QUICK MOVING SURFACE LOW IS EXPECTED TO MOVE ACROSS SOUTHERN
LAKE MICHIGAN TONIGHT. THIS SYSTEM LOOKS TO SPAWN SOME
THUNDERSTORM ACTIVITY EARLY THIS EVENING OVER SOUTHERN PORTIONS OF
THE LAKE. SOME OF THESE STORMS COULD BE SEVERE WITH STRONG WIND
GUSTS AND HAIL. OTHERWISE...FARTHER NORTH...EXPECT 30 TO SOME 35
KT EAST-NORTHEASTERLY GALES TO PERSIST TONIGHT BEFORE ABATING
LATE.
NORTHERLY FLOW IS EXPECTED TO SET UP LAKE-WIDE ON TUESDAY IN THE
WAKE OF TONIGHTS LOW. ONCE THIS OCCURS...IT LOOKS LIKE THERE WILL
BE A PROLONGED PERIOD OF EAST-NORTHEASTERLY FLOW OVER LAKE
MICHIGAN THROUGH THE REST OF THE WEEK...AND POSSIBLY THROUGH THE
UPCOMING WEEKEND AS WELL. DURING THIS PERIOD...SURFACE HIGH
PRESSURE IS EXPECTED TO DOMINATE OVER SOUTHERN CANADA AND THE
UPPER GREAT LAKES REGION...WHILE A COUPLE OF LOW PRESSURE SYSTEMS
TRACK EASTWARD SOUTH OF THE LAKES. EACH OF THESE LOWS WILL LIKELY
RESULT IN A PERIOD OF STRONGER EAST-NORTHEASTERLY FLOW OVER THE
LAKE. THE FIRST ONE EXPECTED TO IMPACT THE LAKE WEDNESDAY INTO
THURSDAY...THEN THE SECOND LOW IS POSSIBLE OVER THE WEEKEND. WHILE
GALE FORCE WINDS ARE CURRENTLY NOT ANTICIPATED...SOME 25 TO 30 KT
FLOW WILL LIKELY RESULT IN LARGE WAVES AND SMALL CRAFT CONDITIONS
OVER THE SOUTHERN LAKE MICHIGAN NEAR SHORES.
KJB
&&
.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:
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Area Forecast Discussion
National Weather Service Lincoln IL
633 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 00Z TAFS through 00Z Tuesday evening)
Issued at 633 PM CDT Mon Apr 25 2016
VFR conditions will prevail at all TAF sites next 24hrs. Clouds
are high based around 7kft and am expecting sct-bkn clouds through
the evening. HRRR still shows some pcpn developing this evening
and moving across central IL, but think it will be near
SPI/DEC only. So will only have VCSH at these two sites and not
add til pcpn begins to showup on radar. Based on satellite loop,
must be some sort of CAP keeping storms from getting out of had.
Overnight once the frontal boundary pushes past the sites, skies
will become scattered. Boundary should push far enough south that
pcpn is not expected at any of the sites tomorrow. However, lower
clouds around 3.5kft will become broken at all sites. Winds will
be southerly, but then become southwest overnight and then
westerly tomorrow or variable with the front passing through late
tonight.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Geelhart
LONG TERM...BAK
AVIATION...Auten
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1015 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 /REST OF TONIGHT/...
ISSUED AT 941 PM EDT MON APR 25 2016
UPDATE...
CURRENT TRENDS MATCH FORECAST...SO NO CHANGES. RAIN HAS STAYED OUT
OF CENTRAL INDIANA SO FAR...AND IS STILL NOT EXPECTED TO START
ENTERING THE NORTHERN COUNTIES UNTIL TUE 03Z. CURRENT RADAR MOSAIC
IS SHOWING A FEW ISOLATED SHOWERS AND THUNDERSTORMS JUST TO THE
WEST OF THE NORTHERN COUNTIES THAT COULD FILTER INTO THE AREA
AT THAT POINT. CURRENT TEMPS ACROSS THE AREA ARE GENERALLY IN THE
LOW 70S AND ARE PROJECTED TO BOTTOM OUT IN THE LOW 60S. UPDATED
GRIDS HAVE BEEN SENT.
PREVIOUS DISCUSSION...
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 260300Z IND TAF UPDATE/...
ISSUED AT 1015 PM EDT MON APR 25 2016
STILL DOES NOT LOOK LIKE CONVECTIVE COVERAGE WILL NOT BE ENOUGH TO
PUT IN THE TAF.
PREVIOUS DISCUSSION FOLLOWS...
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/TDUD
SHORT TERM...PUMA
LONG TERM....JH
AVIATION...MK
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
956 PM EDT MON APR 25 2016
.UPDATE...
THE NEAR TERM 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 /REST OF TONIGHT/...
ISSUED AT 941 PM EDT MON APR 25 2016
UPDATE...
CURRENT TRENDS MATCH FORECAST...SO NO CHANGES. RAIN HAS STAYED OUT
OF CENTRAL INDIANA SO FAR...AND IS STILL NOT EXPECTED TO START
ENTERING THE NORTHERN COUNTIES UNTIL TUE 03Z. CURRENT RADAR MOSAIC
IS SHOWING A FEW ISOLATED SHOWERS AND THUNDERSTORMS JUST TO THE
WEST OF THE NORTHERN COUNTIES THAT COULD FILTER INTO THE AREA
AT THAT POINT. CURRENT TEMPS ACROSS THE AREA ARE GENERALLY IN THE
LOW 70S AND ARE PROJECTED TO BOTTOM OUT IN THE LOW 60S. UPDATED
GRIDS HAVE BEEN SENT.
PREVIOUS DISCUSSION...
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/TDUD
SHORT TERM...PUMA
LONG TERM....JH
AVIATION...MK
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
749 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 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 747 PM EDT MON APR 25 2016
CONDL TS THREAT STILL EXISTS THIS EVENING AS IMPULSE OVR
NRN WI CONTS EWD. HWVR SO FAR SCT ACTIVITY HAS BEEN CONFINED TO
NEWD ARC OF RTN LL THETA-E RIDGE. THIS IS XPCD TO FOLD EWD THROUGH
MID EVENING COMMENSURATE W/CONTD VEERING OF LL FLW AND SHLD SPRT
CONTD UPSTREAM STORM DVLPMNT/INTENSIFICATION THROUGH MID EVENING
HWVR TIMING ADJUSTMENTS TWD RECENT RAP GUIDANCE WERE FOLLOWED.
REGARDLESS PRIMARILY VFR CONDS XPCD THROUGH THE PD. SOMEWHAT BTR
SATURATION/POOLED LL MSTR XPCD INVOF KFWA TWD MORNING AS FNTL
BNDRY STALLS THROUGH CNTRL IN W/A PD OF MVFR CIG RESTRICTION
PLAUSIBLE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...FISHER
SHORT TERM...FISHER
LONG TERM...AGD
AVIATION...T
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AREA FORECAST DISCUSSION
National Weather Service Topeka KS
616 AM CDT SUN APR 24 2016
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 338 AM CDT SUN APR 24 2016
A closed upper low was located over southern WY per the 08Z water
vapor imagery, and a shortwave was rotating around the base of the
upper low across the CO/NM state line. A surface low pressure system
was gradually deepening over southwest SD. This has allowed
southerly winds to remain up through the morning which continues to
advect moisture from the Gulf of Mexico north. An area of elevated
showers and thunderstorms have developed just west of the forecast
area within an area of isentropic assent.
For this morning, the HRRR/RAP/NAM solutions seem to be handling
the elevated precip fairly well so far. The showers should fall
apart during the mid to late morning hours as the isentropic lift
weakens. The main concern for today remains the potential for severe
storms later in the afternoon and early evening. Models prog the
shortwave currently over the CO/NM state line to be lifting through
north central KS by the late afternoon. Models also show the dryline
setting up across north central KS with increasing low level
convergence along the boundary. Moderate instability around 2000
J/kg may develop just ahead of the dryline as mid level lapse rates
steepen to 7.5 or 8 C/km. With forecast soundings showing a mainly
unidirectional profile and deep layer shear sufficient for supercell
storms, there is the potential for splitting storms and some very
large hail. Initially low level winds remain veered to the SSW and
as a result low level shear parameters are not that impressive for
tornadoes. So it appears that any tornado risk will be dependent on
whether local effects can cause surface winds to back. With a slower
progression to the boundary, Think storm initiation could occur just
to the west of the forecast area between 2 and 5 pm. The forecast
shows increasing POPs into the evening hours anticipating a broken
line of storms to move across northern KS.
Along with the thunderstorms this afternoon and this evening, south
winds should become strong by this afternoon with gusts between 30
and 40 MPH possible. Models show a strong pressure gradient setting
up along the turnpike. Because of this, think there could be a few
hours that sustained winds near 30 MPH with gusts over 40 MPH
through the flint hills and will be issuing a wind advisory for
Morris, Wabaunsee, Lyon, Osage and Coffey counties to account for
this potential.
With the morning showers expected to fall apart by the late morning,
think there should be enough insolation along with decent mixing of
the boundary layer for temps to warm into the upper 70s or around 80
this afternoon. There should be a pretty good gradient in lows temps
as models hang the boundary up across the forecast area. With some
dryer air moving in behind the boundary, lows are forecast to fall
to around 50 across north central KS, while northeast and east
central KS stay in the warm moist air with temps around 60 by Monday
morning.
.LONG TERM...(Monday through Saturday)
Issued at 338 AM CDT SUN APR 24 2016
By Monday morning the frontal boundary is progged to be over far
east central Kansas with any residual showers and thunderstorms
dissipating at this time. There is a slight chance for storms to
redevelop in the afternoon and early evening over east central
Kansas given the weak convergence along the front, however with the
subsident air aloft associated with weak upper ridging, most areas
should remain dry. Dewpoints rise to the upper 50s/lower 60s coupled
with lighter winds around 10 mph, conditions will feel warm and
muggy with highs near 80 degrees.
On Monday evening, the upper trough axis is centered over the
southwest CONUS, with the lee trough beginning to form over eastern
Colorado. The ECMWF and NAM runs respectively continue to develop
light qpf amounts near the boundary (generally south of Interstate
70) with some isentropic lift increasing as moisture return builds
northward. The ECMWF runs have seemed overdone with the amount of
precipitation so have sided closer to the NAM with a slight chance
mention through the morning hours.
A stout EML builds northward into the area as the warm front lifts
dewpoint temps into the lower 60s in the late afternoon Tuesday.
Both the NAM and GFS are signaling higher dewpoints, temperatures
near 80 degrees, therefore the amount of sfc CAPE in the 3000-4000
J/KG range in the late afternoon seems probable. Weakening CIN as
the capping inversion erodes could trigger an isolated storm or two
within the warm sector or just ahead of the dryline across north
central Kansas by late afternoon. Sfc winds back to the southeast at
this time while a 55 kt southerly mid level jet streak enters
central Kansas. Effective bulk shear is fairly similar across the
models at 45 to 50 kts. Low level helicity from 0-1 km shear
increase to near 30 kts by 00Z as the low level jet enhances and the
main upper low pushes into the area. All guidance is pretty robust
in developing scattered convection in the 7 PM to midnight time
frame over northeast Kansas. Optimal low level and mid level shear
parameters, ample instability, and lowering LCL heights pose a
tornado threat, in addition to the large hail and damaging winds.
Only major change to the forecast in this period was to increase
pops to a definite probability after 00Z Wednesday.
As the low pressure system phases over the central plains Wednesday,
speed of the low slows lingering showers and thunderstorms through
portions of the day Wednesday. With the high moisture profiles in
the area and the slowing system, it is possible we could have
isolated flash flooding issues especially for areas near the
Nebraska border. Severe storms are not expected on Wednesday. The
system is progged to exit Wednesday evening as northerly winds and
cool advection increase on Thursday. Thursday may be the only dry
day of the week with highs in the 60s and clearing skies.
The next slow moving upper low builds over the southwest CONUS
before ejecting over the southern and central Plains Friday into
Saturday. Placement of the trough axis still varies from the GFS to
ECMWF, however both are signaling multiple rounds of thunderstorms,
with some potential for strong to severe convection on Saturday
evening.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday Morning)
Issued at 616 AM CDT SUN APR 24 2016
High res models show the elevated showers remaining to the north
of the terminals this morning. Therefore anticipate VFR conditions
prevailing through the afternoon. There is some potential for TS
to impact the terminals this evening. The HRRR/ARW/NMM suggest
convection may only be a scattered so confidence in storms at the
terminals is to low to add a tempo or prevailing group. Although
have based the timing of the VCTS on the HRRR forecast. Have
inserted some MVFR CIGS late tonight as the GFS and NAM show low
levels saturating ahead of the frontal boundary.
&&
.TOP Watches/Warnings/Advisories...
Wind Advisory from noon today to 7 PM CDT this evening for
KSZ037-038-054-055-058.
&&
$$
SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS JACKSON KY
1014 PM EDT MON APR 25 2016
.UPDATE...
ISSUED AT 1014 PM EDT MON APR 25 2016
CLOUDS ARE SCARCE OVERALL...AND HAVE BACKED OFF ON SKY COVER FOR A
WHILE LONGER TONIGHT. OTHERWISE...THE BLENDING OF OBS INTO THE
FORECAST RESULTED IN LITTLE CHANGE.
UPDATE ISSUED AT 717 PM EDT MON APR 25 2016
THE UPDATE MAINLY BLENDS LATE DAY OBS INTO THE NIGHT TIME
FORECAST...WITH NO SIGNIFICANT CHANGES.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 243 PM EDT MON APR 25 2016
HIGH PRESSURE RIDGE AXIS HAS CONTINUED TO SHIFT EAST TODAY...WITH
MODEST RETURN FLOW SETTING UP ACROSS KENTUCKY WITH AT TIMES GUSTY
SOUTHWEST WINDS. DAYTIME MIXING HAS BROUGHT DEWPOINTS BACK DOWN
INTO THE MID TO UPPER 40S IN MANY AREAS...A GOOD 5 TO 10 DEGREES
UNDER WHAT MODELS HAD BEEN ADVERTISING YESTERDAY. WITH THIS DRIER
AIR...ANY TERRAIN INDUCED CONVECTION HAS BEEN KEPT AT
BAY...LEADING TO A DRY AFTERNOON ACROSS EASTERN KENTUCKY. AS
INSTABILITY DROPS OFF THIS EVENING...CU SHOULD DISSIPATE QUITE A
BIT...LEADING TO A RATHER PLEASANT EVENING AS TEMPERATURES QUICKLY
COOL OFF UNDER THE MOSTLY CLEAR SKIES...ESPECIALLY IN THE VALLEYS.
THIS WILL SET UP A RIDGE/VALLEY SPLIT TONIGHT WITH SHELTERED VALLEYS
FALLING BACK INTO THE MID 50S...WHILE THE MIXED RIDGES STAY IN THE
LOWER 60S.
TOMORROW...A SHORTWAVE PUSHING INTO NEW ENGLAND...WILL SEND A
SURFACE BOUNDARY SOUTH ACROSS SOUTHERN OHIO. WHILE MOISTURE WILL
CONTINUE TO SLOWLY INCREASE AHEAD OF THIS BOUNDARY...FEEL THAT
MODELS MAY STILL BE OVERDOING SURFACE MOISTURE AND ALLOWING FOR
WAY TOO MUCH CONVECTION. UNTIL SOMETHING CAN FORM ALONG THE
BOUNDARY...WHICH LIKELY WON`T HAPPEN UNTIL LATE AFTERNOON AS AN
APPROACHING VORT MAX CROSSES THE REGION...WE`LL BE HARD PRESSED
TO SEE MUCH CONVECTION AS WE WILL BE LACKING TRIGGERS. ALSO...THE
IMPRESSIVE INSTABILITY ON THE MODELS MAY BE A BIT OVERDONE AS
WELL...SO THAT LENDS ITSELF TO LESS CONVECTION AS WELL. BY LATE IN
THE DAY (AFTER 21Z)...THE THREAT FOR SHOWERS AND STORMS MOVING IN
FROM THE NORTH SHOULD INCREASE AS ACTIVITY FIRES ALONG THE SURFACE
BOUNDARY AND DRIFTS SOUTH AND EAST. STORM MOVEMENT SHOULD BE MORE
TO THE EAST WITH THE STEERING FLOW...SO STILL SOME QUESTION HOW
FAR SOUTH CONVECTION WILL REACH AND WILL BE MAINLY DETERMINED BY
OUTFLOW BOUNDARIES...PUSHING CONVECTION SOUTHWARD. THUS...HARD TO
GO ABOVE CHANCE POPS THROUGH THE EVENING AS THERE REMAINS TOO MUCH
UNCERTAINTY ON RAIN CHANCES. ALSO...WHILE WE ARE IN A MARGINAL
AREA FOR SEVERE STORMS TOMORROW...OVERALL SHEAR IS VERY
UNIMPRESSIVE. IF THE INSTABILITY IS ALSO LESS IMPRESSIVE LIKE I
ANTICIPATE...THAN THE SEVERE STORM CHANCES WILL BE MINIMAL.
HOWEVER...SOME SMALL HAIL COULD STILL BE SEEN BY THE STRONGEST
STORMS.
AS THE VORT MAX AND INSTABILITY EXITS BY LATE TUESDAY
EVENING...WE`LL HAVE SHORTWAVE RIDGING BUILDING IN FOR THE SECOND
HALF OF THE NIGHT...WHICH WOULD LEND ITSELF TO BEING MUCH QUIETER
THROUGH MUCH OF THE NIGHT. HOWEVER...GIVEN THE PROXIMITY OF THE
SURFACE BOUNDARY AND ANY OUTFLOW BOUNDARIES OVER THE AREA...WILL
MAINTAIN SOME ISOLATED SHOWERS/STORMS THROUGH THE NIGHT. GIVEN THE
INCREASED CLOUD COVER...TEMPERATURES WILL BE FAIRLY MILD...ONLY
FALLING A TOUCH UNDER 60 FOR MOST AREAS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 359 PM EDT MON APR 25 2016
AN ACTIVE PATTERN WILL BE IN STORE THROUGH THE PERIOD. AN UPPER
LEVEL LOW WILL GRADUALLY LIFT NORTHEAST OUT OF THE PLAINS AND
EVENTUALLY GET ABSORBED INTO THE CYCLONIC FLOW ASSOCIATED WITH A
DEEP EASTERN CANADIAN SYSTEM THROUGH THE END OF THE WORK
WEEK. SHORT WAVE ENERGY...ALONG WITH A LINGERING SURFACE FRONT
WILL BRING BOUTS OF UNSETTLED WEATHER TO THE OHIO AND TENNESSEE
VALLEYS THROUGH THURSDAY NIGHT. RIDGING WILL THEN MOVE IN ACROSS
THE MISSISSIPPI VALLEY ON FRIDAY...PROVIDING SOME TEMPORARY DRY
WEATHER. MEANWHILE...ANOTHER TROUGH WILL BE TAKING SHAPE ACROSS
THE WESTERN CONUS...WITH PIECES OF ENERGY EJECTING EASTWARD INTO
THE MISSISSIPPI VALLEY AND ALLOWING A RETURN OF UNSETTLED WEATHER
TO THE REGION SATURDAY THROUGH MONDAY.
WEDNESDAY THROUGH THURSDAY NIGHT WILL FEATURE SCATTERED TO
NUMEROUS SHOWERS AND STORMS ACROSS EASTERN KENTUCKY. HAVE ALLOWED
FOR SOMEWHAT OF A DIURNAL INFLUENCE TO THE POPS TO MITIGATE SOME
OF THE LOWER CONFIDENCE IN TIMING INDIVIDUAL FORCING MECHANISMS.
FRIDAY AND FRIDAY NIGHT LOOK DRY AS SHORT WAVE RIDGING MOVES IN.
THERE IS DISAGREEMENT ON HOW QUICKLY FORCING AND MOISTURE RETURN
FROM THE WEST ON SATURDAY. HAVE UNDERCUT THE POPS A TAD...BUT HAVE
STILL ALLOWED FOR A CHANCE OF SHOWERS IN THE AFTERNOON. THE
OVERALL BEST CHANCE OF POPS WILL COME IN ON SUNDAY...WITH
LINGERING CHANCES POSSIBLE INTO MONDAY...WITH TROUGHINESS
REMAINING ACROSS THE OHIO VALLEY.
TEMPERATURES WILL AVERAGE ABOVE NORMAL THROUGH THE WEEKEND...WITH
HIGHS AVERAGING IN THE UPPER 70S TO AROUND 80 AND LOWS IN THE 50S.
READINGS WILL DROP BACK CLOSER TO SEASONAL NORMALS BY EARLY NEXT
WEEK...AS HIGHS RETREAT TO THE LOWER 70S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 717 PM EDT MON APR 25 2016
PREDOMINANTLY VFR IS FORECAST DURING THE PERIOD...WITH LIGHT WINDS
TONIGHT...PICKING UP OUT OF THE SOUTHWEST AT GENERALLY 5 TO
10 KTS ON TUESDAY. THERE WILL BE AN INCREASE IN CLOUDS AT ABOUT
4-5K FT AGL...MAINLY DURING THE DAY TUESDAY...WITH AT LEAST
SCATTERED THUNDERSTORMS EXPECTED BY LATE IN THE DAY. CONFIDENCE IN
COVERAGE AND TIMING OF STORMS IS STILL FAIRLY LOW. THE STRONGEST
STORMS COULD PRODUCE GUSTY WINDS AND HAIL.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...KAS
LONG TERM...GEOGERIAN
AVIATION...HAL
[top]
Area Forecast Discussion
National Weather Service Paducah KY
835 PM CDT MON APR 25 2016
.UPDATE...
Issued at 835 PM CDT Mon Apr 25 2016
Convective trends this evening appear to matching closer to the
GFS, Canadian, NAM-WRF (NMM & ARW versions), and the HRRR guidance
for tonight through Tuesday night. Current convection over
Central/Southwest Illinois poised along low level convergence
smack in the middle of a SSW-NNE oriented theta-e plume. As the
night progresses, this theta-e axis should become more oriented
west to east, pulling richer moisture toward Southwest
Indiana/Southeast Illinois/Northwest Kentucky between 3 am and 7
am CDT. This could produce isolated shower and thunderstorm
activity in that area. Noticed even SPC has modified their
convective outlook northwest of the WFO PAH CWA reflecting a
greater severe potential along the I-70 corridor over MO/IL for
the rest of tonight.
The adjustment this evening for Tuesday will be an increase in
coverage of showers and thunderstorms during the middle and late
afternoon hours, a lesser coverage (especially along the AR/TN
borders) Tuesday evening, then a ramp up of PoPs/Weather late
Tuesday night. Numerical guidance has been hinting at the
propagation of an MCS southeast across the area late Tuesday
night.
Other sensible weather elements, such as sky, temperatures,
dewpoints, and winds appear to be in line. Was not surprise by the
expansion of the SPC Day 2 Marginal risk area over the area for
Tuesday. Cannot rule a stray storm producing severe or near severe
hail or wind.
&&
.SHORT TERM...(Tonight through Wednesday night)
Issued at 237 PM CDT Mon Apr 25 2016
Models are in pretty decent agreement on the track of our
upcoming weather system. Models show a surface low over eastern
Colorado at 12z Tuesday, moving over southeast Nebraska by 00z
Thursday. The warm front associated with this low will be hanging
out north of the PAH forecast area at 12z Tuesday, dropping south
into our region by Tuesday evening and remaining in our area
through Wednesday. The surface low will then bring the trailing
cold front across our area Wednesday night.
Showers and thunderstorms can be expected to develop along the
warm front Tuesday into Tuesday night, and along and ahead of the
cold front Wednesday into Wednesday night. ECMWF and GFS are in
good agreement showing scattered showers and thunderstorms Tuesday
into Tuesday evening, with the best chances in our northern
counties along the warm front. Models then show a push of moisture
into our western counties late Tuesday night, spreading east
through the day Wednesday, continuing into Wednesday night. Went
with increasing chances from north to south late tonight into
Tuesday, the went with likely pops north to good chance south
Tuesday night. Went with likely pops area wide on Wednesday, with
chances gradually decreasing from the west Wednesday night.
SPC has included all but our southern Kentucky counties in a
marginal risk for severe storms Tuesday into possibly Tuesday
evening due to some pretty impressive instability along and south
of the warm front. For Wednesday into Wednesday evening, our
western two thirds of counties are in a slight risk and the rest
of our area in a marginal as the approaching cold front moves into
our already unstable air mass. As for rainfall amounts, our
overall totals should be highest across our northern counties
where the warm front will trigger some heavier rainfall Tuesday
into Tuesday night, but isolated higher amounts will be possible
area wide Wednesday into Wednesday evening with thunderstorm
activity.
Our southerly winds will bring not only plenty of moisture into
the region for the next couple of days, but continued very warm
conditions. Temperatures will remain unseasonably warm through
Wednesday night. Low temperatures tonight through Wednesday night
will mostly be in the lower to middle 60s. Highs Tuesday will be
in the 80 to 85 degree range, then the additional cloud
cover/precipitation on Wednesday will drop readings back several
degrees into the middle to upper 70s.
.LONG TERM...(Thursday through Monday)
Issued at 237 PM CDT Mon Apr 25 2016
Average confidence in the long term due to multiple rain events and
some model disparity where timing, track, and coverage are concerned
with these events.
On Thursday small precipitation chances exist over the northeast
third/half of the CWA on the back side of a system that crosses the
region Wednesday night. The frontal boundary associated with this
system is forecast to become stationary just to our south Thursday
night and right now that period looks dry.
A closed H5 low moving northeast out of the four corners region on
Friday will induce a surface low on the aforementioned boundary over
the panhandle of Texas which will begin to generate an overrunning
rain event that is forecast to develop showers and thunderstorms
into our far western counties on Friday. Models not seeing eye to
eye too well with the onset of precipitation so it may not begin as
early as originally thought.
As the system slowly approaches, precipitation chances continue to
ramp up Friday into Friday night, with the highest chances area wide
being Saturday and Saturday night with the passage of the system. In
its wake, precipitation chances are expected to taper off from the
west but will linger from Sunday into Monday due to the presence of
upstream upper level energy and decent moisture.
Temperatures remain at or above normal through the period.
&&
.AVIATION...
Issued at 636 PM CDT Mon Apr 25 2016
A rather challenging forecast with the 00z Tuesday WFO PAH TAF
package. An evolving warm frontal zone is working from southwest
to northeast across the each of the TAF sites. As the frontal zone
sharpens, kept the trend of reducing from VFR to MVFR ceilings,
starting after 06z Tuesday at KCGI and around 11z at KOWB. Added a
mention of showers to KCGI, KPAH, KOWB TAF sites, as these sites
will see the most peristent lift for shower activity.
&&
.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
UPDATE...Smith
SHORT TERM...RST
LONG TERM...JP
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1158 PM EDT MON APR 25 2016
.AVIATION...
SHOWERS AND THUNDERSTORMS WILL EXIT TO THE EAST EARLY THIS MORNING
AS LOW PRESSURE LIFTS THROUGH THE REGION. TRAILING COLD FRONT WILL
LEAD IN AN EXTENSIVE LOW STRATUS DECK FROM SOUTH TO NORTH THROUGH
THE MORNING HOURS. THIS WILL RESULT IN AN EXTENDED PERIOD OF
IFR/LOW MVFR CEILING...PERHAPS ACCOMPANIED BY SOME VISIBILITY
RESTRICTIONS AND POCKETS OF DRIZZLE. THIS MOISTURE WILL HOLD FIRM
THROUGH THE DAY...SIMPLY A GRADUAL INCREASE IN CEILING HEIGHT DURING
THIS TIME.
FOR DTW...RAPID REDUCTION IN THUNDERSTORM CHANCES BEYOND 06Z. BRIEF
PERIOD OF SOUTH-SOUTHWEST FLOW IN ADVANCE OF A STRONG COLD FRONT
EXPECTED TO LIFT THROUGH MID MORNING. SOLID INCREASE IN LOW STRATUS
/IFR-LOW MVFR/ DURING THIS TIME. IMMEDIATE WIND SHIFT TO NORTHWEST
WITH FRONTAL PASSAGE...VEERING TO NORTHEAST THROUGH THE DAY.
//DTW THRESHOLD PROBABILITIES...
* MEDIUM IN CEILINGS BELOW 5000 FEET PRIOR TO 12Z...HIGH THEREAFTER
ON TUESDAY.
&&
.PREV DISCUSSION...ISSUED 808 PM EDT MON APR 25 2016
UPDATE...
INBOUND CONVECTION JUST UPSTREAM EVOLVING AS EXPECTED THUS
FAR...CONVECTIVE VIGOR AND OVERALL COVERAGE SUSTAINED BY INCREASING
MID LEVEL FORCING IMPINGING ON A WEAKLY UNSTABLE PROFILE. QUESTION
MOVING FORWARD REMAINS THE CHARACTER OF THE CONVECTION AS IT
MIGRATES INTO OUR CONSIDERABLY LESS RECEPTIVE THERMODYNAMIC
ENVIRONMENT. WELL DEFINED WARM/STATIONARY FRONTAL BOUNDARY NOW
ARCING ACROSS FAR SOUTHWEST ZONES /ADRIAN TO HOWELL/...A NOTABLY
COOLER AND DRIER NEAR SURFACE ENVIRONMENT EAST OF THE BOUNDARY
LEAVING NO TANGIBLE INSTABILITY WITHIN THE LOWEST 2500 FT. UPTICK
IN MID LEVEL INSTABILITY AS THETA-E QUALITY INCREASES IMMEDIATELY IN
ADVANCE OF THE SURFACE WAVE WILL SUPPLY THE NECESSARY BACKGROUND TO
SUPPORT AN INCREASING COVERAGE OF LARGELY ELEVATED CONVECTION.
WITH THAT SAID...REMAINS PLAUSIBLE THAT ISOLATED CELLS COULD ATTAIN
SUFFICIENT ORGANIZATION/DEPTH TO GENERATE STRONGER GUSTS/LARGE HAIL.
RISK REMAINS HIGHER ALONG THE SOUTHWEST FRINGE OF THE FORECAST AREA
/WEST OF THE HWY 23 CORRIDOR...SOUTH OF M-59/...BOTH THE RAP AND
HRRR SUSTAIN UP TO 500 J/KG OF SBCAPE ALONG THE WESTERN EDGE OF
THE DEFINED LOW LEVEL INSTABILITY GRADIENT.
PREV DISCUSSION...ISSUED 342 PM EDT MON APR 25 2016
DISCUSSION...
INCREASINGLY AGITATED CU OVER SOUTHWEST LOWER MICHIGAN SIGNALS THE
ARRIVAL OF DEEPER MID-LEVEL MOISTURE, THE LEAD EDGE OF WHICH IS
SUPPORTING A FEW LIGHT SHOWERS INVOF THE THUMB. ARRIVAL OF THIS
MOISTURE DURING PEAK HEATING WILL BRING AN INCREASING CHANCE OF
SHOWERS BETWEEN NOW AND 00Z OVER MOST OF SOUTHEAST MICHIGAN. THE
ENVIRONMENT WILL REMAIN LARGELY CAPPED THROUGH THIS TIME SO THERE
EXISTS ONLY A VERY LOW CHANCE OF THUNDER THIS AFTERNOON.
NONETHELESS, A DEEP AND VERY WELL-MIXED BOUNDARY LAYER SPORTING DRY
ADIABATIC LAPSE RATES THROUGH THE LOWEST 5KFT WILL SUPPORT STRONG
WIND GUST POTENTIAL WITHIN ANY ORGANIZED SHOWER DEVELOPMENT. THE
LACK OF INSTABILITY AND AND WEAK AMBIENT WIND FIELD THIS AFTN WILL
LIMIT POTENTIAL TO LESS THAN 50 MPH.
ATTENTION FOR THE REMAINDER OF THE NIGHT TURNS TO THE COLD FRONT
READILY EVIDENT IN VISIBLE IMAGERY OVER SOUTHERN WISCONSIN AND
WESTERN ILLINOIS WHERE CONVECTIVE INITIATION IS JUST GETTING
UNDERWAY. CONVECTION WILL INCREASE IN COVERAGE AND INTENSITY
COINCIDENT WITH DIURNAL DESTABILIZATION, BUT WILL LIKELY BECOME
ELEVATED AND LARGELY SUPPORTED BY THE STRENGTHENING LLJ AS IT
CROSSES LAKE MICHIGAN THIS EVENING. INCREASING LLJ TO 30-40KTS WILL
STEEPEN MID-LEVEL LAPSE RATES AND SUPPORT PERSISTENCE OF NOCTURNAL
CONVECTION AS IT WORKS ACROSS SE MICHIGAN 02-06Z. SURFACE-BASED
INSTABILITY WILL BE NON-EXISTENT NORTH OF THE SURFACE FRONT AND
QUITE LIMITED TO THE SOUTH GIVEN NOCTURNAL TIMING. THE EXCEPTION
WILL BE THE FAR SOUTHWEST PORTIONS OF THE CWA CURRENTLY HIGHLIGHTED
IN THE 1630Z SPC SLIGHT RISK AREA. A FEW HUNDRED J/KG CAPE
PERSISTING DURING THE SUNSET HOURS WILL YIELD AN OPPORTUNITY FOR
UPSTREAM CONVECTION TO PROPAGATE INTO THE AREA CARRYING A BETTER-
DEFINED WIND THREAT PRIOR TO BECOMING ELEVATED. NORTH AND EAST,
WITHIN THE MARGINAL RISK AREA/STILL SOUTH OF THE SURFACE WARM FRONT,
THE RATHER SHALLOW NOCTURNAL INVERSION WILL NOT BE IMPERVIOUS TO
DOWNDRAFTS, WHICH COULD BE ON THE STRONGER SIDE GIVEN THE AMPLE LOW-
LEVEL DRY AIR IN PLACE IN THE PRE-STORM ENVIRONMENT. A LOW END
SEVERE RISK THEREFORE EXISTS THROUGH ABOUT 06Z FOR ALL LOCATIONS
SOUTH OF I-69. NORTH OF THE I-69 CORRIDOR, THE STRONGLY FORCED
ENVIRONMENT WILL HELP OFFSET THE LACK OF ELEVATED INSTABILITY, SO
SUB-SEVERE HAIL CANNOT BE RULED OUT.
COLD FRONT WILL WORK THROUGH THE CWA BY 18Z TUESDAY LEADING TO A
SIZEABLE HIGH TEMPERATURE GRADIENT ACROSS THE CWA...NEAR 70 ALONG
THE OHIO BORDER AND UPPER 40S IN THE THUMB. STEEP LAPSE BOUNDARY
LAYER RATES SUPPORTED BY ONGOING CAA AND THE INTRUSION OF SHALLOW
MOISTURE PRESENTLY EVIDENT BY LOW CLOUDS ON VIS IMAGERY OVER THE
NORTHERN GREAT LAKES WILL SUPPORT PATCHY DRIZZLE IN ADDITION
OVERCAST SKIES FOR MUCH OF THE DAY...WITH THE EXCEPTION OF LOCATIONS
SOUTH OF I-94/SOUTH OF THE COLD FRONT. COOL AIRMASS CHARACTERIZED BY
H85 TEMPS IN THE SINGLE DIGITS WILL SUPPORT HIGHS IN THE 50S ON
WEDNESDAY. DRY RESIDENT AIRMASS AND CONFLUENT FLOW ALOFT WILL
SUPPORT MOSTLY CLEAR SKIES FOR MOST OF WEDNESDAY.
LOW PRESSURE SYSTEM WILL SLIDE SOUTH OF THE OHIO BORDER ON THURSDAY
ALLOWING RAIN TO SPREAD NORTHWARD ACROSS SOUTHERN LOWER MICHIGAN. AN
ISOLATED THUNDERSTORM IS ALSO A POSSIBILITY THURSDAY AFTERNOON AS
BETTER INSTABILITY WORKS INTO OUR EXTREME SOUTHERN COUNTIES. STRONG
HIGH PRESSURE BUILDS SOUTHWARD OUT OF NORTHERN ONTARIO ON FRIDAY AND
REMAINS SITUATED OVER THE REGION FOR AT LEAST THE FIRST HALF OF THE
WEEKEND. MODELS ARE UNDECIDED FOR SUNDAY...EITHER KEEPING SOUTHEAST
MICHIGAN DRY OR HAVING A LOW PRESSURE SYSTEM /AND RESULTING RAIN/
FOR SUNDAY. WILL HAVE TO FINE TUNE THIS FORECAST FOR SUNDAY AS THE
WEEK PROGRESSES.
MARINE...
A FRONTAL BOUNDARY THAT WAS STALLED ACROSS THE CENTRAL GREAT LAKE
HAS DRIFTED SOUTHWARD THROUGH THE DAY. A LOW PRESSURE SYSTEM TO THE
WEST IS TRACKING ALONG THIS BOUNDARY WHILE PULLING A WARM FRONT INTO
THE SOUTHERN GREAT LAKES...WHICH WILL PHASE WITH THE EXISTING FRONT.
THIS HAS RESULTED IN EASTERLY FLOW ACROSS ALL OF THE EASTERN LAKES.
SOUTHWESTERLY FLOW WILL ATTEMPT TO LIFT OVER LAKE ERIE THIS EVENING
BUT THE LOW WILL TRACK RIGHT ACROSS SOUTHERN LOWER MICHIGAN WHICH
WILL KEEP PRIMARILY AN EASTERLY/NORTHEASTERLY FLOW. IN
ADDITION...SHOWERS WILL CONTINUE ALONG THE FRONT WITH A CHANCE OF
THUNDERSTORMS LATER THIS EVENING.
SMALL CRAFT ADVISORIES REMAIN IN EFFECT FOR A PORTION OF THE
NEARSHORE WATERS OF LAKE HURON INCLUDING SAGINAW BAY. WINDS AND
WAVES WILL BE MARGINAL...WITH THE EXCEPTION OF SAGINAW BAY ALREADY
GUSTING OVER 25 KNOTS...BUT SUSTAINED EAST/NORTHEAST FLOW OVER LAKE
HURON WILL CAUSE WAVE HEIGHTS TO BUILD ALONG THE SHORELINE. WINDS
WILL DECREASE WHILE BECOMING NORTHERLY ON TUESDAY AS HIGH PRESSURE
BEGINS TO MOVE BACK INTO THE REGION.
HYDROLOGY...
LOW PRESSURE AND AN ATTENDING COLD FRONT WILL MOVE THROUGH SOUTHEAST
MICHIGAN LATE TODAY INTO TONIGHT WITH NUMEROUS SHOWERS AND EMBEDDED
THUNDERSTORMS BECOMING INCREASINGLY LIKELY FROM LATE AFTERNOON INTO
THE EVENING HOURS. WHILE WIDESPREAD BASIN AVERAGE RAINFALL WILL
HOVER AROUND ONE QUARTER OF AN INCH...LOCALIZED RAINFALL AMOUNTS OF
ONE HALF TO THREE QUARTERS OF AN INCH WILL BE POSSIBLE FROM LATE
TODAY INTO EARLY TUESDAY MORNING. THE BULK OF THE RAIN IS FORECAST
BETWEEN 00-06Z TONIGHT WHEN THUNDERSTORMS WILL BE MOST LIKELY.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...SMALL CRAFT ADVISORY FROM 8 AM TO 4 PM EDT TUESDAY FOR LHZ442-443.
SMALL CRAFT ADVISORY UNTIL 4 PM EDT TUESDAY FOR LHZ421-422-441.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....MR
UPDATE.......MR
DISCUSSION...JVC/RK
MARINE.......DRK
HYDROLOGY....DRK
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
808 PM EDT MON APR 25 2016
.UPDATE...
INBOUND CONVECTION JUST UPSTREAM EVOLVING AS EXPECTED THUS
FAR...CONVECTIVE VIGOR AND OVERALL COVERAGE SUSTAINED BY INCREASING
MID LEVEL FORCING IMPINGING ON A WEAKLY UNSTABLE PROFILE. QUESTION
MOVING FORWARD REMAINS THE CHARACTER OF THE CONVECTION AS IT
MIGRATES INTO OUR CONSIDERABLY LESS RECEPTIVE THERMODYNAMIC
ENVIRONMENT. WELL DEFINED WARM/STATIONARY FRONTAL BOUNDARY NOW
ARCING ACROSS FAR SOUTHWEST ZONES /ADRIAN TO HOWELL/...A NOTABLY
COOLER AND DRIER NEAR SURFACE ENVIRONMENT EAST OF THE BOUNDARY
LEAVING NO TANGIBLE INSTABILITY WITHIN THE LOWEST 2500 FT. UPTICK
IN MID LEVEL INSTABILITY AS THETA-E QUALITY INCREASES IMMEDIATELY IN
ADVANCE OF THE SURFACE WAVE WILL SUPPLY THE NECESSARY BACKGROUND TO
SUPPORT AN INCREASING COVERAGE OF LARGELY ELEVATED CONVECTION.
WITH THAT SAID...REMAINS PLAUSIBLE THAT ISOLATED CELLS COULD ATTAIN
SUFFICIENT ORGANIZATION/DEPTH TO GENERATE STRONGER GUSTS/LARGE HAIL.
RISK REMAINS HIGHER ALONG THE SOUTHWEST FRINGE OF THE FORECAST AREA
/WEST OF THE HWY 23 CORRIDOR...SOUTH OF M-59/...BOTH THE RAP AND
HRRR SUSTAIN UP TO 500 J/KG OF SBCAPE ALONG THE WESTERN EDGE OF
THE DEFINED LOW LEVEL INSTABILITY GRADIENT.
&&
.AVIATION...ISSUED 715 PM EDT MON APR 25 2016
ATTENTION THROUGH EARLY TONIGHT CENTERED ON CONVECTION NOW
ORGANIZING ACROSS THE LAKE MICHIGAN/NORTHERN IL CORRIDOR. EXISTING
DOWNSTREAM ENVIRONMENT WILL FAVOR THE MAINTAINANCE OF AT LEAST
POCKETS OF THUNDERSTORMS WITHIN A BROADER REGION OF SHOWERS
FUNNELING DOWNSTREAM. LATEST RADAR TRENDS AND MODEL GUIDANCE
CONTINUE TO FAVOR A LOCAL ARRIVAL OF THIS PRECIPITATION AT ALL
TERMINALS WITHIN THE 02Z-05Z WINDOW. THUNDERSTORM SEVERITY HINDERED
BY LIMITED LOW INSTABILITY RELATIVE TO POINTS UPSTREAM...WILL
CONTINUE TO MONITOR TRENDS GOING FORWARD. AGGRESSIVE SOUTHWARD
EXPANSION OF LOW LEVEL MOISTURE ACCOMPANYING THE COLD FRONTAL
PASSAGE WILL THEN LEAD EXTENSIVE IFR/LOW MVFR CIGS DURING THE EARLY-
MID MORNING HOURS. THIS MOISTURE WILL HOLD FIRM THROUGH THE
DAY...SIMPLY A GRADUAL INCREASE IN CEILING HEIGHT DURING THIS TIME.
FOR DTW...WARM FRONT NOW ANCHORED NEAR ANN ARBOR SHOWING NO
ADDITIONAL SIGNS OF FORWARD PROGRESS...LEAVING WINDS PARKED AT A SE
TO ESE DIRECTION THIS EVENING. THUNDER POTENTIAL REMAINS DEFINED
WITHIN THE 04Z-06Z PERIOD...VERY LOW PROBABILITY FOR A STORM TO
APPROACH SEVERE LIMITS AND WILL CONTINUE TO MONITOR UPSTREAM TRENDS.
VFR CONDITIONS OUTSIDE OF TSRA UNTIL STRATUS ACCOMPANIES COLD
FRONTAL PASSAGE AROUND DAYBREAK. IMMEDIATE POST-FRONTAL WINDS OUT
OF THE NORTHWEST TUESDAY MORNING...VEERING TO NORTHEAST THROUGH THE
DAY.
//DTW THRESHOLD PROBABILITIES...
* MEDIUM IN THUNDERSTORMS IMPACTING THE TERMINAL BETWEEN 04Z AND 06Z.
* MEDIUM IN CEILINGS BELOW 5000 FEET PRIOR TO 12Z...HIGH THEREAFTER
ON TUESDAY.
&&
.PREV DISCUSSION...ISSUED 342 PM EDT MON APR 25 2016
DISCUSSION...
INCREASINGLY AGITATED CU OVER SOUTHWEST LOWER MICHIGAN SIGNALS THE
ARRIVAL OF DEEPER MID-LEVEL MOISTURE, THE LEAD EDGE OF WHICH IS
SUPPORTING A FEW LIGHT SHOWERS INVOF THE THUMB. ARRIVAL OF THIS
MOISTURE DURING PEAK HEATING WILL BRING AN INCREASING CHANCE OF
SHOWERS BETWEEN NOW AND 00Z OVER MOST OF SOUTHEAST MICHIGAN. THE
ENVIRONMENT WILL REMAIN LARGELY CAPPED THROUGH THIS TIME SO THERE
EXISTS ONLY A VERY LOW CHANCE OF THUNDER THIS AFTERNOON.
NONETHELESS, A DEEP AND VERY WELL-MIXED BOUNDARY LAYER SPORTING DRY
ADIABATIC LAPSE RATES THROUGH THE LOWEST 5KFT WILL SUPPORT STRONG
WIND GUST POTENTIAL WITHIN ANY ORGANIZED SHOWER DEVELOPMENT. THE
LACK OF INSTABILITY AND AND WEAK AMBIENT WIND FIELD THIS AFTN WILL
LIMIT POTENTIAL TO LESS THAN 50 MPH.
ATTENTION FOR THE REMAINDER OF THE NIGHT TURNS TO THE COLD FRONT
READILY EVIDENT IN VISIBLE IMAGERY OVER SOUTHERN WISCONSIN AND
WESTERN ILLINOIS WHERE CONVECTIVE INITIATION IS JUST GETTING
UNDERWAY. CONVECTION WILL INCREASE IN COVERAGE AND INTENSITY
COINCIDENT WITH DIURNAL DESTABILIZATION, BUT WILL LIKELY BECOME
ELEVATED AND LARGELY SUPPORTED BY THE STRENGTHENING LLJ AS IT
CROSSES LAKE MICHIGAN THIS EVENING. INCREASING LLJ TO 30-40KTS WILL
STEEPEN MID-LEVEL LAPSE RATES AND SUPPORT PERSISTENCE OF NOCTURNAL
CONVECTION AS IT WORKS ACROSS SE MICHIGAN 02-06Z. SURFACE-BASED
INSTABILITY WILL BE NON-EXISTENT NORTH OF THE SURFACE FRONT AND
QUITE LIMITED TO THE SOUTH GIVEN NOCTURNAL TIMING. THE EXCEPTION
WILL BE THE FAR SOUTHWEST PORTIONS OF THE CWA CURRENTLY HIGHLIGHTED
IN THE 1630Z SPC SLIGHT RISK AREA. A FEW HUNDRED J/KG CAPE
PERSISTING DURING THE SUNSET HOURS WILL YIELD AN OPPORTUNITY FOR
UPSTREAM CONVECTION TO PROPAGATE INTO THE AREA CARRYING A BETTER-
DEFINED WIND THREAT PRIOR TO BECOMING ELEVATED. NORTH AND EAST,
WITHIN THE MARGINAL RISK AREA/STILL SOUTH OF THE SURFACE WARM FRONT,
THE RATHER SHALLOW NOCTURNAL INVERSION WILL NOT BE IMPERVIOUS TO
DOWNDRAFTS, WHICH COULD BE ON THE STRONGER SIDE GIVEN THE AMPLE LOW-
LEVEL DRY AIR IN PLACE IN THE PRE-STORM ENVIRONMENT. A LOW END
SEVERE RISK THEREFORE EXISTS THROUGH ABOUT 06Z FOR ALL LOCATIONS
SOUTH OF I-69. NORTH OF THE I-69 CORRIDOR, THE STRONGLY FORCED
ENVIRONMENT WILL HELP OFFSET THE LACK OF ELEVATED INSTABILITY, SO
SUB-SEVERE HAIL CANNOT BE RULED OUT.
COLD FRONT WILL WORK THROUGH THE CWA BY 18Z TUESDAY LEADING TO A
SIZEABLE HIGH TEMPERATURE GRADIENT ACROSS THE CWA...NEAR 70 ALONG
THE OHIO BORDER AND UPPER 40S IN THE THUMB. STEEP LAPSE BOUNDARY
LAYER RATES SUPPORTED BY ONGOING CAA AND THE INTRUSION OF SHALLOW
MOISTURE PRESENTLY EVIDENT BY LOW CLOUDS ON VIS IMAGERY OVER THE
NORTHERN GREAT LAKES WILL SUPPORT PATCHY DRIZZLE IN ADDITION
OVERCAST SKIES FOR MUCH OF THE DAY...WITH THE EXCEPTION OF LOCATIONS
SOUTH OF I-94/SOUTH OF THE COLD FRONT. COOL AIRMASS CHARACTERIZED BY
H85 TEMPS IN THE SINGLE DIGITS WILL SUPPORT HIGHS IN THE 50S ON
WEDNESDAY. DRY RESIDENT AIRMASS AND CONFLUENT FLOW ALOFT WILL
SUPPORT MOSTLY CLEAR SKIES FOR MOST OF WEDNESDAY.
LOW PRESSURE SYSTEM WILL SLIDE SOUTH OF THE OHIO BORDER ON THURSDAY
ALLOWING RAIN TO SPREAD NORTHWARD ACROSS SOUTHERN LOWER MICHIGAN. AN
ISOLATED THUNDERSTORM IS ALSO A POSSIBILITY THURSDAY AFTERNOON AS
BETTER INSTABILITY WORKS INTO OUR EXTREME SOUTHERN COUNTIES. STRONG
HIGH PRESSURE BUILDS SOUTHWARD OUT OF NORTHERN ONTARIO ON FRIDAY AND
REMAINS SITUATED OVER THE REGION FOR AT LEAST THE FIRST HALF OF THE
WEEKEND. MODELS ARE UNDECIDED FOR SUNDAY...EITHER KEEPING SOUTHEAST
MICHIGAN DRY OR HAVING A LOW PRESSURE SYSTEM /AND RESULTING RAIN/
FOR SUNDAY. WILL HAVE TO FINE TUNE THIS FORECAST FOR SUNDAY AS THE
WEEK PROGRESSES.
MARINE...
A FRONTAL BOUNDARY THAT WAS STALLED ACROSS THE CENTRAL GREAT LAKE
HAS DRIFTED SOUTHWARD THROUGH THE DAY. A LOW PRESSURE SYSTEM TO THE
WEST IS TRACKING ALONG THIS BOUNDARY WHILE PULLING A WARM FRONT INTO
THE SOUTHERN GREAT LAKES...WHICH WILL PHASE WITH THE EXISTING FRONT.
THIS HAS RESULTED IN EASTERLY FLOW ACROSS ALL OF THE EASTERN LAKES.
SOUTHWESTERLY FLOW WILL ATTEMPT TO LIFT OVER LAKE ERIE THIS EVENING
BUT THE LOW WILL TRACK RIGHT ACROSS SOUTHERN LOWER MICHIGAN WHICH
WILL KEEP PRIMARILY AN EASTERLY/NORTHEASTERLY FLOW. IN
ADDITION...SHOWERS WILL CONTINUE ALONG THE FRONT WITH A CHANCE OF
THUNDERSTORMS LATER THIS EVENING.
SMALL CRAFT ADVISORIES REMAIN IN EFFECT FOR A PORTION OF THE
NEARSHORE WATERS OF LAKE HURON INCLUDING SAGINAW BAY. WINDS AND
WAVES WILL BE MARGINAL...WITH THE EXCEPTION OF SAGINAW BAY ALREADY
GUSTING OVER 25 KNOTS...BUT SUSTAINED EAST/NORTHEAST FLOW OVER LAKE
HURON WILL CAUSE WAVE HEIGHTS TO BUILD ALONG THE SHORELINE. WINDS
WILL DECREASE WHILE BECOMING NORTHERLY ON TUESDAY AS HIGH PRESSURE
BEGINS TO MOVE BACK INTO THE REGION.
HYDROLOGY...
LOW PRESSURE AND AN ATTENDING COLD FRONT WILL MOVE THROUGH SOUTHEAST
MICHIGAN LATE TODAY INTO TONIGHT WITH NUMEROUS SHOWERS AND EMBEDDED
THUNDERSTORMS BECOMING INCREASINGLY LIKELY FROM LATE AFTERNOON INTO
THE EVENING HOURS. WHILE WIDESPREAD BASIN AVERAGE RAINFALL WILL
HOVER AROUND ONE QUARTER OF AN INCH...LOCALIZED RAINFALL AMOUNTS OF
ONE HALF TO THREE QUARTERS OF AN INCH WILL BE POSSIBLE FROM LATE
TODAY INTO EARLY TUESDAY MORNING. THE BULK OF THE RAIN IS FORECAST
BETWEEN 00-06Z TONIGHT WHEN THUNDERSTORMS WILL BE MOST LIKELY.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...SMALL CRAFT ADVISORY FROM 8 AM TO 4 PM EDT TUESDAY FOR LHZ442-443.
SMALL CRAFT ADVISORY UNTIL 4 PM EDT TUESDAY FOR LHZ421-422-441.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
UPDATE.......MR
AVIATION.....MR
DISCUSSION...JVC/RK
MARINE.......DRK
HYDROLOGY....DRK
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
734 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 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 730 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 FROM ACROSS WI TO
LWR MI 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...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
437 PM EDT SUN APR 24 2016
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 437 PM EDT SUN APR 24 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW CONFLUENT WNW FLOW OVER
THE UPPER GREAT LAKES BTWN A NRN STREAM TROF OVER SE CANADA INTO NEW
ENGLAND AND LOW AMPLITUDE SRN STREAM RIDGING OVER THE MISSISSIPPI
VALLEY AHEAD OF A MID LEVEL LOW CENTERED NEAR RAPID CITY. COLD AIR
THAT HAS EXPANDED UNDER THE SE CANADA TROF AND WARM AIR PUSHING INTO
THE UPPER MISSISSIPPI VALLEY AHEAD OF SRN STREAM MID LEVEL LOW HAS
RESULTED IN A TIGHTENING THERMAL GRADIENT/BAROCLINIC ZONE ACROSS THE
UPPER MISSISSIPPI VALLEY/GREAT LAKES. PER 12Z RAOBS...850MB TEMPS
RANGED FROM -16C AT MOOSONEE TO -10C AT PICKLE LAKE TO 14C AT THE
TWIN CITIES. UPPER DIVERGENCE IN RIGHT ENTRANCE OF 120+KT UPPER JET
EXTENDING ACROSS NRN ONTARIO INTO SRN QUEBEC IS AIDING PCPN
DEVELOPMENT WITHIN THE BAROCLINIC ZONE OVER THE UPPER MISSISSIPPI
VALLEY INTO THE WRN GREAT LAKES. HOWEVER...PCPN TODAY HAS BEEN
DISPLACED FARTHER SW THAN INDICATED BY THE MODELS YESTERDAY. THIS IS
ESPECIALLY TRUE OF THE MDT/HEAVY PCPN WHICH HAS STAYED SW AND S OF
THE WI/MI BORDER. ALL DAY...RADAR IMAGERY LOOP HAS SHOWED PCPN
DEVELOPMENT BEING FOCUSED CLOSER TO THE SFC FRONTAL BOUNDARY ACROSS
SRN MN TO ECNTRL WI. AS A RESULT...MEANINGFUL 850/700MB MOISTURE
TRANSPORT HAS NOT ABLE TO EXTEND NE INTO UPPER MI. THUS...PCPN
AMOUNTS TODAY HAVE BEEN MUCH LESS THAN ANTICIPATED.
TONIGHT...INFLUENCE OF THE SE CANADA TROF IS FCST TO RELAX
SOME...ALLOWING MID LEVEL LOW OVER THE WRN PLAINS TO SHIFT E TO ERN
SD/SW MN. PROGRESSION OF THESE FEATURES SHOULD ALLOW BETTER MOISTURE
TRANSPORT/LOW-MID LEVEL FGEN TO SHIFT NE INTO UPPER MI. UPPER
DIVERGENCE IN RIGHT ENTRANCE OF UPPER JET ALSO BECOMES MORE
FAVORABLY POSITIONED OVER THE AREA. AS A RESULT...EXPECT
STEADIER/HEAVIER RAIN TO LIFT NE INTO THE FCST AREA TONIGHT.
HOWEVER...GIVEN RECENT MODEL PERFORMANCE IN BEING TOO AGGRESSIVE
LIFTING PCPN N...WOULD NOT BE SURPRISED IF THE HEAVIER PCPN
STRUGGLES TO SPREAD NE INTO THE FCST AREA.
ON MON...REMNANT OF THE MID LEVEL LOW THAT WILL BE OVER ERN SD/SW MN
MON MORNING WILL RAPIDLY WEAKEN AS IT SHEARS EASTWARD INTO THE
CONFLUENT FLOW OVER THE UPPER LAKES. ALTHOUGH WEAKENING...INCREASING
DEEP LAYER FORCING PER QVECTORS AND LINGERING FGEN WILL KEEP PERIODS
OF RAIN GOING THRU THE DAY. MAY SEE A BREAK OR A PERIOD OF
DIMINISHED RAINFALL LATE TONIGHT/MON MORNING...ESPECIALLY ACROSS THE
S...BEFORE DEEP LAYER FORCING INCREASES.
SINCE RAINFALL TODAY WAS NOT NEARLY AS MUCH AS EXPECTED...DO NOT
ANTICIPATE ANY ISSUES WITH RAINFALL TONIGHT/MON. WILL PROBABLY STILL
SEE SOME PERIODS OF MDT/HVY RAINFALL...BUT AMOUNTS TONIGHT/MON ARE
NOW EXPECTED TO BE MOSTLY IN THE 1-2 INCH RANGE WHICH SHOULD NOT
POSE ANY WATER ISSUES.
MIN TEMPS TONIGHT WILL BE IN THE MID/UPPER 30S. WITH CLOUDS/FREQUENT
RAIN ON MON...FAVORED THE LOW END OF AVBL GUIDANCE. EXPECT HIGH
TEMPS IN THE UPPER 30S/LWR 40S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 PM EDT SUN APR 24 2016
SHORTWAVE MOVING THROUGH MON NIGHT WILL LEAD TO MAINLY RAIN...BUT
COLD AIR MOVING IN FROM THE N MAY TURN SOME PRECIP TO SNOW OVER NRN
UPPER MI. HOWEVER...PRECIP IS DIMINISHING AND MOVING OUT WHILE THE
COLDER AIR IS MOVING IN...SO ANY SNOWFALL AMOUNTS WILL BE LIGHT AND
SHOULD MAINLY BE ON GRASSY SURFACES.
TUE THROUGH NEXT SUN LOOKS COOL AND DRY AS CANADIAN HIGH PRESSURE
DOMINATES. 850MB TEMPS HOVERING A DEGREE OR TWO BELOW 0C WILL KEEP
HIGH TEMPS IN THE MID 40S TO MID 50S (MAYBE SOME UPPER 50S) AND WITH
PARTLY CLOUDY TO MOSTLY CLEAR SKIES...LOWS WILL BE NEAR TO BELOW
FREEZING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 148 PM EDT SUN APR 24 2016
WITH A STATIONARY FRONT REMAINING S OF UPPER MI THRU MON...EXPECT
PERIODS OF RAIN DURING THIS FCST PERIOD WITH CONDITIONS GENERALLY
SETTLING INTO THE IFR CATEGORY AT KIWD/KCMX/KSAW. BEST CHC OF
PREVAILING LIFR CONDITIONS WILL BE LATE TONIGHT/MON MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 437 PM EDT SUN APR 24 2016
WITH HIGH PRES BUILDING INTO NORTHERN ONTARIO AND WEAKENING LOW PRES
TRACKING E ALONG A STALLED FRONT S OF UPPER MI...STRONG E TO NE
WINDS WILL BE THE RULE ACROSS LAKE SUPERIOR THRU MON. OVER THE
WESTERN LAKE WHERE COASTAL CONVERGENCE/FUNNELING ENHANCE E TO NE
WINDS...GALE FORCE WINDS ARE EXPECTED THRU MON. STRONGEST WIND
GUSTS...POSSIBLY UP TO 45KT...WILL OCCUR MON AFTN. ACROSS THE REST
OF LAKE SUPERIOR...WINDS WILL STEADILY INCREASE FROM W TO E
TONIGHT...REACHING 20-30KT BY SUNRISE MON. WINDS WILL SLOWLY
DIMINISH MON NIGHT/TUE MORNING...BUT MORE SO TUE AFTN/NIGHT AS THE
NORTHERN ONTARIO HIGH PRES BUILDS INTO THE UPPER LAKES. E TO NE
WINDS GENERALLY UNDER 20KT WILL PREVAIL WED. GIVEN THE E TO NE WIND
DIRECTION...WINDS WILL BE STRONGEST OVER WRN LAKE SUPERIOR. WINDS
WILL REMAIN UNDER 20KT THU/FRI WITH HIGH PRES OVER THE AREA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 8 PM EDT /7 PM CDT/ MONDAY FOR LSZ162.
GALE WARNING FROM 5 AM TO 8 PM EDT MONDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
345 PM EDT SUN APR 24 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 424 AM EDT SUN APR 24 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW A CONFLUENT WNW
FLOW ALF OVER THE UPR LKS BTWN A NRN BRANCH CUTOFF LO OVER NRN
QUEBEC AND A SRN BRANCH FLOW DOMINATING THE CONUS WITH A STRONG
SHRTWV IN THIS FLOW DRIFTING SLOWLY ENEWD THRU WYOMING. THERE IS A
GOOD DEAL OF CLD COVER OVER UPR MI WITH WAA IN TIGHTENING BAROCLINIC
ZN TO THE NE OF H85 WARM FNT STRETCHING FM THE NRN PLAINS INTO WRN
WI...BUT AXIS OF HEAVIEST RA EARLY THIS MRNG STRETCHES FM NCENTRAL
MN ESEWD INTO NCENTRAL WI CLOSER TO THE H85 FNT. THERE ARE MORE SCT
RA SHOWERS DVLPG IN NRN MN WHERE UPR DVGC IN RRQ OF 120KT H3 JET
CORE CENTERED JUST SW OF JAMES BAY IS AIDING LIFT OF MOISTER AIR
SHOWN ON THE 00Z INL RAOB. LINGERING LLVL DRY AIR SHOWN ON THE 00Z
GRB/APX RAOBS THAT IS REPRESENTATIVE OF CONDITIONS OVER THE CWA HAS
SLOWED DOWN THE ARRIVAL OF THIS EXPANDING PCPN AND THE NE PUSH OF
THE RA IN WI CLOSER TO THE H85 WARM FNT. THE AIR IN ONTARIO IS EVEN
DRIER WITH 00Z PWAT AS LO AS 0.14 INCH AT YPL.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/QPF ASSOCIATED
WITH TIGHTENING BAROCLINIC ZN OVER UPR MI UNDER PERSISTENT UPR DVGC
IN RRQ OF H3 JET MAX MOVING ONLY SLOWLY E THRU TNGT. CLOSER APRCH
TNGT OF SHRTWV NOW IN WYOMING WILL INTENSIFY THE DYNAMIC SUPPORT.
CONFIDENCE IS INCRSG THE HEAVIER RA WL FALL NEAR THE WI BORDER...BUT
THERE ARE STILL SOME MODEL INCONSISTENCIES AS TO THE PLACEMENT OF
THE AXIS OF HEAVIER RA RELATED TO POSITION OF SHARPER FGEN AND
IMPACT OF DRY AIR TO THE N.
TDAY...H85 THERMAL GRADIENT/UPR DVGC IN RRQ OF UPR JET CORE TO THE
NE IS FCST TO EXPAND OVER UPR MI TODAY...AND MOST OF THE MODELS
SHIFT AXIS OF HEAVIER PCPN TO THE N ACCORDINGLY. SO WL EXPAND HIER
POPS NE THRU THE CWA EXCEPT OVER THE KEWEENAW...WHICH WL BE CLOSER
TO THE DEEPER DRY AIR JUST TO THE N. HOWEVER...WITH LINGERING LLVL
DRY AIR...FAVOR THE 00Z REGIONAL CNDN MODEL FCST. THIS MODEL SHOWS
THE HIER QPF REMAINING CLOSER TO THE WI BORDER WHERE EVEN THE 00Z
NAM SHOWS MORE PERSISTENT AXIS OF SHARPER H85-7 FGEN/UVV AND WHERE
PWAT IS FCST TO INCRS TO AOA 1 INCH /ABOUT 225 PCT OF NORMAL/. THIS
FCST IS ALSO MORE CONSISTENT WITH LOCATION OF AXIS OF HEAVIER RA FM
NCENTRAL MN INTO NCENTRAL WI EARLY THIS MRNG...THE LOCATION OF WHICH
MAY HINT AT A BNDRY WHICH MAY ACT TO INTERCEPT MSTR INFLOW. WITH THE
CLDS AND RA DVLPG...EXPECT WELL BLO NORMAL MAX TEMPS THAT WL LIKELY
STAY UNDER 40 AT SOME PLACES NEAR LK SUP.
TNGT...WITH SLOW APRCH OF SHRTWV FM THE WSW TNGT...UPR DVGC OVER AND
MSTR TRANSPORT INTO ARE FCST TO INCRS OVERNGT. SO EXPECT HEAVIER RA
TO EXPAND TO THE NE. THE CNDN MODEL STILL SEEMS TO BE ON THE RIGHT
TRACK SHOWING THE AXIS OF HEAVIER PCPN DIMINISHING A BIT WITH THE
SHIFT TO THE NE GIVEN PERSISTENT DRY AIR IN THAT DIRECTION THAT WILL
TEND TO SHARPEN THE NRN EDGE OF THE PCPN/HEAVIER RA. TOTAL RA THRU
12Z MON WL REACH AS MUCH AS 1.50 TO 2.00 INCHES NEAR THE WI BORDER.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 345 PM EDT SUN APR 24 2016
SHORTWAVE MOVING THROUGH MON NIGHT WILL LEAD TO MAINLY RAIN...BUT
COLD AIR MOVING IN FROM THE N MAY TURN SOME PRECIP TO SNOW OVER NRN
UPPER MI. HOWEVER...PRECIP IS DIMINISHING AND MOVING OUT WHILE THE
COLDER AIR IS MOVING IN...SO ANY SNOWFALL AMOUNTS WILL BE LIGHT AND
SHOULD MAINLY BE ON GRASSY SURFACES.
TUE THROUGH NEXT SUN LOOKS COOL AND DRY AS CANADIAN HIGH PRESSURE
DOMINATES. 850MB TEMPS HOVERING A DEGREE OR TWO BELOW 0C WILL KEEP
HIGH TEMPS IN THE MID 40S TO MID 50S (MAYBE SOME UPPER 50S) AND WITH
PARTLY CLOUDY TO MOSTLY CLEAR SKIES...LOWS WILL BE NEAR TO BELOW
FREEZING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 148 PM EDT SUN APR 24 2016
WITH A STATIONARY FRONT REMAINING S OF UPPER MI THRU MON...EXPECT
PERIODS OF RAIN DURING THIS FCST PERIOD WITH CONDITIONS GENERALLY
SETTLING INTO THE IFR CATEGORY AT KIWD/KCMX/KSAW. BEST CHC OF
PREVAILING LIFR CONDITIONS WILL BE LATE TONIGHT/MON MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 AM EDT SUN APR 24 2016
WITH TIGHTENING PRES GRADIENT BETWEEN HI PRES BUILDING INTO NORTHERN
ONTARIO AND A LO PRES MOVING E FROM THE PLAINS ALONG A STALLED LO
PRES TROUGH TO THE S...EXPECT NE WINDS INCREASING TO 25 TO 30 KTS
THRU MON. THE STRONGEST WINDS WILL BE OVER THE WESTERN LAKE...WHERE
GALES TO 35-40 KTS ARE FORECAST THIS AFTERNOON THRU MON WITH A
COASTLINE CONFIGURATION THAT WILL ACCENTUATE THE NE FLOW. EXPANDED
THE GALE WARNING FOR LSZ162 TO INCLUDE LSZ263 FOR LATE TONIGHT AND
MON. WINDS WILL GRADUALLY DIMINISH MON NIGHT THRU TUE AS A HI PRES
BUILDS INTO THE UPPER LAKES. N TO E WINDS GENERALLY UNDER 20 KTS WILL
THEN PREVAIL ON WED AND THU WITH A HI PRES RIDGE AXIS IN PLACE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 8 PM EDT /7 PM CDT/ MONDAY FOR LSZ162.
GALE WARNING FROM 5 AM TO 8 PM EDT MONDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
149 PM EDT SUN APR 24 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 424 AM EDT SUN APR 24 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW A CONFLUENT WNW
FLOW ALF OVER THE UPR LKS BTWN A NRN BRANCH CUTOFF LO OVER NRN
QUEBEC AND A SRN BRANCH FLOW DOMINATING THE CONUS WITH A STRONG
SHRTWV IN THIS FLOW DRIFTING SLOWLY ENEWD THRU WYOMING. THERE IS A
GOOD DEAL OF CLD COVER OVER UPR MI WITH WAA IN TIGHTENING BAROCLINIC
ZN TO THE NE OF H85 WARM FNT STRETCHING FM THE NRN PLAINS INTO WRN
WI...BUT AXIS OF HEAVIEST RA EARLY THIS MRNG STRETCHES FM NCENTRAL
MN ESEWD INTO NCENTRAL WI CLOSER TO THE H85 FNT. THERE ARE MORE SCT
RA SHOWERS DVLPG IN NRN MN WHERE UPR DVGC IN RRQ OF 120KT H3 JET
CORE CENTERED JUST SW OF JAMES BAY IS AIDING LIFT OF MOISTER AIR
SHOWN ON THE 00Z INL RAOB. LINGERING LLVL DRY AIR SHOWN ON THE 00Z
GRB/APX RAOBS THAT IS REPRESENTATIVE OF CONDITIONS OVER THE CWA HAS
SLOWED DOWN THE ARRIVAL OF THIS EXPANDING PCPN AND THE NE PUSH OF
THE RA IN WI CLOSER TO THE H85 WARM FNT. THE AIR IN ONTARIO IS EVEN
DRIER WITH 00Z PWAT AS LO AS 0.14 INCH AT YPL.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/QPF ASSOCIATED
WITH TIGHTENING BAROCLINIC ZN OVER UPR MI UNDER PERSISTENT UPR DVGC
IN RRQ OF H3 JET MAX MOVING ONLY SLOWLY E THRU TNGT. CLOSER APRCH
TNGT OF SHRTWV NOW IN WYOMING WILL INTENSIFY THE DYNAMIC SUPPORT.
CONFIDENCE IS INCRSG THE HEAVIER RA WL FALL NEAR THE WI BORDER...BUT
THERE ARE STILL SOME MODEL INCONSISTENCIES AS TO THE PLACEMENT OF
THE AXIS OF HEAVIER RA RELATED TO POSITION OF SHARPER FGEN AND
IMPACT OF DRY AIR TO THE N.
TDAY...H85 THERMAL GRADIENT/UPR DVGC IN RRQ OF UPR JET CORE TO THE
NE IS FCST TO EXPAND OVER UPR MI TODAY...AND MOST OF THE MODELS
SHIFT AXIS OF HEAVIER PCPN TO THE N ACCORDINGLY. SO WL EXPAND HIER
POPS NE THRU THE CWA EXCEPT OVER THE KEWEENAW...WHICH WL BE CLOSER
TO THE DEEPER DRY AIR JUST TO THE N. HOWEVER...WITH LINGERING LLVL
DRY AIR...FAVOR THE 00Z REGIONAL CNDN MODEL FCST. THIS MODEL SHOWS
THE HIER QPF REMAINING CLOSER TO THE WI BORDER WHERE EVEN THE 00Z
NAM SHOWS MORE PERSISTENT AXIS OF SHARPER H85-7 FGEN/UVV AND WHERE
PWAT IS FCST TO INCRS TO AOA 1 INCH /ABOUT 225 PCT OF NORMAL/. THIS
FCST IS ALSO MORE CONSISTENT WITH LOCATION OF AXIS OF HEAVIER RA FM
NCENTRAL MN INTO NCENTRAL WI EARLY THIS MRNG...THE LOCATION OF WHICH
MAY HINT AT A BNDRY WHICH MAY ACT TO INTERCEPT MSTR INFLOW. WITH THE
CLDS AND RA DVLPG...EXPECT WELL BLO NORMAL MAX TEMPS THAT WL LIKELY
STAY UNDER 40 AT SOME PLACES NEAR LK SUP.
TNGT...WITH SLOW APRCH OF SHRTWV FM THE WSW TNGT...UPR DVGC OVER AND
MSTR TRANSPORT INTO ARE FCST TO INCRS OVERNGT. SO EXPECT HEAVIER RA
TO EXPAND TO THE NE. THE CNDN MODEL STILL SEEMS TO BE ON THE RIGHT
TRACK SHOWING THE AXIS OF HEAVIER PCPN DIMINISHING A BIT WITH THE
SHIFT TO THE NE GIVEN PERSISTENT DRY AIR IN THAT DIRECTION THAT WILL
TEND TO SHARPEN THE NRN EDGE OF THE PCPN/HEAVIER RA. TOTAL RA THRU
12Z MON WL REACH AS MUCH AS 1.50 TO 2.00 INCHES NEAR THE WI BORDER.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 413 AM EDT SUN APR 24 2016
SHORTWAVE TROUGH LIFTING ACROSS THE NORTHERN PLAINS COMBINES WITH
SHARP H85 BAROCLINIC ZONE TO SUPPORT MODERATE PERHAPS HEAVY RAIN
MONDAY MORNING. SINCE STRONGEST H85 TEMP GRADIENT AND ASSOCIATED
FRONTOGENSIS REMAINS OVER SOUTHERN TIER OF UPR MICHIGAN...PERFER
MODEL SOLUTIONS THAT DIMINISH QPF AS IT LIFTS OVER NORTHERN TIER
OF CWA IN THE MORNING. GFS AND GEM-REGIONAL FIT INTO THAT CATEGORY.
QUITE A COOL AND DAMP DAY ON MON NO MATTER THE COVERAGE OF THE RAIN.
EXPECT CHILLY READINGS IN THE MID-UPR 30S NEAR LK SUPERIOR AND
ONLY AROUND 40 ELSEWHERE.
PRIMARY SHORTWAVE TROUGH ARRIVES OVER UPPER GREAT LAKES ON MONDAY
AFTN. JET STREAK ROUNDING BASE OF TROUGH AND SOME ELEVATED
INSTABILITY MAY RESULT IN TSRA POSSIBLY SNEAKING INTO SCNTRL CWA
LATE MONDAY AFTN INTO MONDAY EVENING. DID KEEP MENTION OF TSRA OUT
ATTM AS WITH SFC LOW PASSING BY SOUTH OF UPR MICHIGAN...WOULD EXPECT
BEST CHANCES FOR EVEN ELEVATED TSRA OVER EASTERN WI AND ON FARTHER
SOUTH. ARRIVAL OF THE SHORTWAVE TROUGH SHOULD BRING ANOTHER ROUND OF
RAIN TO MAINLY THE SOUTH AND SOUTH CENTRAL IN THE AFTN. COOLER AIR
WORKS ACROSS UPR MICHIGAN MON EVENING AS THE LOW OVER WI SLIDES
EAST. 1000-500MB/850-700MB THICKNESSES AND NAM/GFS SOUNDINGS
INDICATE POTENTIAL FOR SNOW TO BEGIN MIXING WITH RAIN OVER HIGHER
TERRAIN OF NW AND NCNTRL MON EVENING THEN SWITCH OVER TO SNOW
OVERNIGHT MON NIGHT. SINCE THE ARRIVAL OF THE COLD AIR TIMES OUT
WITH DIMINISHING PRECIPITATION...SNOW AMOUNTS MON NIGHT SHOULD STAY
LESS THAN AN INCH...MAINLY ON GRASSY SURFACES.
AFTER THE RAIN/SNOW TO SNOW MOVES OUT LATE MON NIGHT...LOOKS DRY
THROUGH THE REST OF THE WEEK AND INTO NEXT WEEKEND AS HIGH PRESSURE
BUILDS OVER HUDSON BAY AND PERSISTS. DRY EASTERLY FLOW SHOULD KEEP
UPPER MICHIGAN DRY. WITH THE EAST TO NORTHEAST WIND OFF THE HIGH
COOLEST READINGS DURING THE DAYTIME SHOULD BE NEAR LK SUPERIOR.
TEMPS THERE LIKELY WILL REMAIN SLIGHTLY BELOW NORMAL THROUGH THE
WEEK. INLAND TEMPS AND NEAR LK MICHIGAN SHOULD REACH TOWARD NORMAL
BY MID TO LATE WEEK WITH READINGS IN THE 50S TO NEAR 60 BY LATE IN
THE WEEK. INFLUENCE OF THE DRY HIGH PRESSURE SHOULD ALLOW TEMPS AT
NIGHT AWAY FROM THE GREAT LAKES TO FALL INTO THE 20S TO LOW 30S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 148 PM EDT SUN APR 24 2016
WITH A STATIONARY FRONT REMAINING S OF UPPER MI THRU MON...EXPECT
PERIODS OF RAIN DURING THIS FCST PERIOD WITH CONDITIONS GENERALLY
SETTLING INTO THE IFR CATEGORY AT KIWD/KCMX/KSAW. BEST CHC OF
PREVAILING LIFR CONDITIONS WILL BE LATE TONIGHT/MON MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 AM EDT SUN APR 24 2016
WITH TIGHTENING PRES GRADIENT BETWEEN HI PRES BUILDING INTO NORTHERN
ONTARIO AND A LO PRES MOVING E FROM THE PLAINS ALONG A STALLED LO
PRES TROUGH TO THE S...EXPECT NE WINDS INCREASING TO 25 TO 30 KTS
THRU MON. THE STRONGEST WINDS WILL BE OVER THE WESTERN LAKE...WHERE
GALES TO 35-40 KTS ARE FORECAST THIS AFTERNOON THRU MON WITH A
COASTLINE CONFIGURATION THAT WILL ACCENTUATE THE NE FLOW. EXPANDED
THE GALE WARNING FOR LSZ162 TO INCLUDE LSZ263 FOR LATE TONIGHT AND
MON. WINDS WILL GRADUALLY DIMINISH MON NIGHT THRU TUE AS A HI PRES
BUILDS INTO THE UPPER LAKES. N TO E WINDS GENERALLY UNDER 20 KTS WILL
THEN PREVAIL ON WED AND THU WITH A HI PRES RIDGE AXIS IN PLACE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 8 PM EDT /7 PM CDT/ MONDAY FOR LSZ162.
GALE WARNING FROM 5 AM TO 8 PM EDT MONDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
741 AM EDT SUN APR 24 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 424 AM EDT SUN APR 24 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW A CONFLUENT WNW
FLOW ALF OVER THE UPR LKS BTWN A NRN BRANCH CUTOFF LO OVER NRN
QUEBEC AND A SRN BRANCH FLOW DOMINATING THE CONUS WITH A STRONG
SHRTWV IN THIS FLOW DRIFTING SLOWLY ENEWD THRU WYOMING. THERE IS A
GOOD DEAL OF CLD COVER OVER UPR MI WITH WAA IN TIGHTENING BAROCLINIC
ZN TO THE NE OF H85 WARM FNT STRETCHING FM THE NRN PLAINS INTO WRN
WI...BUT AXIS OF HEAVIEST RA EARLY THIS MRNG STRETCHES FM NCENTRAL
MN ESEWD INTO NCENTRAL WI CLOSER TO THE H85 FNT. THERE ARE MORE SCT
RA SHOWERS DVLPG IN NRN MN WHERE UPR DVGC IN RRQ OF 120KT H3 JET
CORE CENTERED JUST SW OF JAMES BAY IS AIDING LIFT OF MOISTER AIR
SHOWN ON THE 00Z INL RAOB. LINGERING LLVL DRY AIR SHOWN ON THE 00Z
GRB/APX RAOBS THAT IS REPRESENTATIVE OF CONDITIONS OVER THE CWA HAS
SLOWED DOWN THE ARRIVAL OF THIS EXPANDING PCPN AND THE NE PUSH OF
THE RA IN WI CLOSER TO THE H85 WARM FNT. THE AIR IN ONTARIO IS EVEN
DRIER WITH 00Z PWAT AS LO AS 0.14 INCH AT YPL.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/QPF ASSOCIATED
WITH TIGHTENING BAROCLINIC ZN OVER UPR MI UNDER PERSISTENT UPR DVGC
IN RRQ OF H3 JET MAX MOVING ONLY SLOWLY E THRU TNGT. CLOSER APRCH
TNGT OF SHRTWV NOW IN WYOMING WILL INTENSIFY THE DYNAMIC SUPPORT.
CONFIDENCE IS INCRSG THE HEAVIER RA WL FALL NEAR THE WI BORDER...BUT
THERE ARE STILL SOME MODEL INCONSISTENCIES AS TO THE PLACEMENT OF
THE AXIS OF HEAVIER RA RELATED TO POSITION OF SHARPER FGEN AND
IMPACT OF DRY AIR TO THE N.
TDAY...H85 THERMAL GRADIENT/UPR DVGC IN RRQ OF UPR JET CORE TO THE
NE IS FCST TO EXPAND OVER UPR MI TODAY...AND MOST OF THE MODELS
SHIFT AXIS OF HEAVIER PCPN TO THE N ACCORDINGLY. SO WL EXPAND HIER
POPS NE THRU THE CWA EXCEPT OVER THE KEWEENAW...WHICH WL BE CLOSER
TO THE DEEPER DRY AIR JUST TO THE N. HOWEVER...WITH LINGERING LLVL
DRY AIR...FAVOR THE 00Z REGIONAL CNDN MODEL FCST. THIS MODEL SHOWS
THE HIER QPF REMAINING CLOSER TO THE WI BORDER WHERE EVEN THE 00Z
NAM SHOWS MORE PERSISTENT AXIS OF SHARPER H85-7 FGEN/UVV AND WHERE
PWAT IS FCST TO INCRS TO AOA 1 INCH /ABOUT 225 PCT OF NORMAL/. THIS
FCST IS ALSO MORE CONSISTENT WITH LOCATION OF AXIS OF HEAVIER RA FM
NCENTRAL MN INTO NCENTRAL WI EARLY THIS MRNG...THE LOCATION OF WHICH
MAY HINT AT A BNDRY WHICH MAY ACT TO INTERCEPT MSTR INFLOW. WITH THE
CLDS AND RA DVLPG...EXPECT WELL BLO NORMAL MAX TEMPS THAT WL LIKELY
STAY UNDER 40 AT SOME PLACES NEAR LK SUP.
TNGT...WITH SLOW APRCH OF SHRTWV FM THE WSW TNGT...UPR DVGC OVER AND
MSTR TRANSPORT INTO ARE FCST TO INCRS OVERNGT. SO EXPECT HEAVIER RA
TO EXPAND TO THE NE. THE CNDN MODEL STILL SEEMS TO BE ON THE RIGHT
TRACK SHOWING THE AXIS OF HEAVIER PCPN DIMINISHING A BIT WITH THE
SHIFT TO THE NE GIVEN PERSISTENT DRY AIR IN THAT DIRECTION THAT WILL
TEND TO SHARPEN THE NRN EDGE OF THE PCPN/HEAVIER RA. TOTAL RA THRU
12Z MON WL REACH AS MUCH AS 1.50 TO 2.00 INCHES NEAR THE WI BORDER.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 413 AM EDT SUN APR 24 2016
SHORTWAVE TROUGH LIFTING ACROSS THE NORTHERN PLAINS COMBINES WITH
SHARP H85 BAROCLINIC ZONE TO SUPPORT MODERATE PERHAPS HEAVY RAIN
MONDAY MORNING. SINCE STRONGEST H85 TEMP GRADIENT AND ASSOCIATED
FRONTOGENSIS REMAINS OVER SOUTHERN TIER OF UPR MICHIGAN...PERFER
MODEL SOLUTIONS THAT DIMINISH QPF AS IT LIFTS OVER NORTHERN TIER
OF CWA IN THE MORNING. GFS AND GEM-REGIONAL FIT INTO THAT CATEGORY.
QUITE A COOL AND DAMP DAY ON MON NO MATTER THE COVERAGE OF THE RAIN.
EXPECT CHILLY READINGS IN THE MID-UPR 30S NEAR LK SUPERIOR AND
ONLY AROUND 40 ELSEWHERE.
PRIMARY SHORTWAVE TROUGH ARRIVES OVER UPPER GREAT LAKES ON MONDAY
AFTN. JET STREAK ROUNDING BASE OF TROUGH AND SOME ELEVATED
INSTABILITY MAY RESULT IN TSRA POSSIBLY SNEAKING INTO SCNTRL CWA
LATE MONDAY AFTN INTO MONDAY EVENING. DID KEEP MENTION OF TSRA OUT
ATTM AS WITH SFC LOW PASSING BY SOUTH OF UPR MICHIGAN...WOULD EXPECT
BEST CHANCES FOR EVEN ELEVATED TSRA OVER EASTERN WI AND ON FARTHER
SOUTH. ARRIVAL OF THE SHORTWAVE TROUGH SHOULD BRING ANOTHER ROUND OF
RAIN TO MAINLY THE SOUTH AND SOUTH CENTRAL IN THE AFTN. COOLER AIR
WORKS ACROSS UPR MICHIGAN MON EVENING AS THE LOW OVER WI SLIDES
EAST. 1000-500MB/850-700MB THICKNESSES AND NAM/GFS SOUNDINGS
INDICATE POTENTIAL FOR SNOW TO BEGIN MIXING WITH RAIN OVER HIGHER
TERRAIN OF NW AND NCNTRL MON EVENING THEN SWITCH OVER TO SNOW
OVERNIGHT MON NIGHT. SINCE THE ARRIVAL OF THE COLD AIR TIMES OUT
WITH DIMINISHING PRECIPITATION...SNOW AMOUNTS MON NIGHT SHOULD STAY
LESS THAN AN INCH...MAINLY ON GRASSY SURFACES.
AFTER THE RAIN/SNOW TO SNOW MOVES OUT LATE MON NIGHT...LOOKS DRY
THROUGH THE REST OF THE WEEK AND INTO NEXT WEEKEND AS HIGH PRESSURE
BUILDS OVER HUDSON BAY AND PERSISTS. DRY EASTERLY FLOW SHOULD KEEP
UPPER MICHIGAN DRY. WITH THE EAST TO NORTHEAST WIND OFF THE HIGH
COOLEST READINGS DURING THE DAYTIME SHOULD BE NEAR LK SUPERIOR.
TEMPS THERE LIKELY WILL REMAIN SLIGHTLY BELOW NORMAL THROUGH THE
WEEK. INLAND TEMPS AND NEAR LK MICHIGAN SHOULD REACH TOWARD NORMAL
BY MID TO LATE WEEK WITH READINGS IN THE 50S TO NEAR 60 BY LATE IN
THE WEEK. INFLUENCE OF THE DRY HIGH PRESSURE SHOULD ALLOW TEMPS AT
NIGHT AWAY FROM THE GREAT LAKES TO FALL INTO THE 20S TO LOW 30S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 739 AM EDT SUN APR 24 2016
AS AREA OF RA OVERSPREADS UPR MI TODAY...EXPECT VFR CONDITIONS AT
TAF ISSUANCE TIME TO DETERIORATE. SINCE IWD WL BE CLOSEST TO AN
APRCHG WARM FNT/DEEPER MSTR...CIGS WL FALL TO IFR QUICKER THERE AND
BY 18Z. SINCE CMX IS FARTHER N INTO MUCH DRIER AIR...THE ONSET OF
IFR CIGS IS NOT LIKELY TO HAPPEN UNTIL LATER TNGT WHEN AN APRCHG UPR
DISTURBANCE WL BRING A BETTER CHC FOR MORE RA TO OVERCOME THE LLVL
DRY AIR. A MORE UPSLOPE NE FLOW WL BRING ABOUT LIFR CONDITIONS AT
SAW LATER TNGT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 AM EDT SUN APR 24 2016
WITH TIGHTENING PRES GRADIENT BETWEEN HI PRES BUILDING INTO NORTHERN
ONTARIO AND A LO PRES MOVING E FROM THE PLAINS ALONG A STALLED LO
PRES TROUGH TO THE S...EXPECT NE WINDS INCREASING TO 25 TO 30 KTS
THRU MON. THE STRONGEST WINDS WILL BE OVER THE WESTERN LAKE...WHERE
GALES TO 35-40 KTS ARE FORECAST THIS AFTERNOON THRU MON WITH A
COASTLINE CONFIGURATION THAT WILL ACCENTUATE THE NE FLOW. EXPANDED
THE GALE WARNING FOR LSZ162 TO INCLUDE LSZ263 FOR LATE TONIGHT AND
MON. WINDS WILL GRADUALLY DIMINISH MON NIGHT THRU TUE AS A HI PRES
BUILDS INTO THE UPPER LAKES. N TO E WINDS GENERALLY UNDER 20 KTS WILL
THEN PREVAIL ON WED AND THU WITH A HI PRES RIDGE AXIS IN PLACE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 11 AM EDT /10 AM CDT/ THIS MORNING TO 8 PM EDT
/7 PM CDT/ MONDAY FOR LSZ162.
GALE WARNING FROM 5 AM TO 8 PM EDT MONDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
425 AM EDT SUN APR 24 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 424 AM EDT SUN APR 24 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW A CONFLUENT WNW
FLOW ALF OVER THE UPR LKS BTWN A NRN BRANCH CUTOFF LO OVER NRN
QUEBEC AND A SRN BRANCH FLOW DOMINATING THE CONUS WITH A STRONG
SHRTWV IN THIS FLOW DRIFTING SLOWLY ENEWD THRU WYOMING. THERE IS A
GOOD DEAL OF CLD COVER OVER UPR MI WITH WAA IN TIGHTENING BAROCLINIC
ZN TO THE NE OF H85 WARM FNT STRETCHING FM THE NRN PLAINS INTO WRN
WI...BUT AXIS OF HEAVIEST RA EARLY THIS MRNG STRETCHES FM NCENTRAL
MN ESEWD INTO NCENTRAL WI CLOSER TO THE H85 FNT. THERE ARE MORE SCT
RA SHOWERS DVLPG IN NRN MN WHERE UPR DVGC IN RRQ OF 120KT H3 JET
CORE CENTERED JUST SW OF JAMES BAY IS AIDING LIFT OF MOISTER AIR
SHOWN ON THE 00Z INL RAOB. LINGERING LLVL DRY AIR SHOWN ON THE 00Z
GRB/APX RAOBS THAT IS REPRESENTATIVE OF CONDITIONS OVER THE CWA HAS
SLOWED DOWN THE ARRIVAL OF THIS EXPANDING PCPN AND THE NE PUSH OF
THE RA IN WI CLOSER TO THE H85 WARM FNT. THE AIR IN ONTARIO IS EVEN
DRIER WITH 00Z PWAT AS LO AS 0.14 INCH AT YPL.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/QPF ASSOCIATED
WITH TIGHTENING BAROCLINIC ZN OVER UPR MI UNDER PERSISTENT UPR DVGC
IN RRQ OF H3 JET MAX MOVING ONLY SLOWLY E THRU TNGT. CLOSER APRCH
TNGT OF SHRTWV NOW IN WYOMING WILL INTENSIFY THE DYNAMIC SUPPORT.
CONFIDENCE IS INCRSG THE HEAVIER RA WL FALL NEAR THE WI BORDER...BUT
THERE ARE STILL SOME MODEL INCONSISTENCIES AS TO THE PLACEMENT OF
THE AXIS OF HEAVIER RA RELATED TO POSITION OF SHARPER FGEN AND
IMPACT OF DRY AIR TO THE N.
TDAY...H85 THERMAL GRADIENT/UPR DVGC IN RRQ OF UPR JET CORE TO THE
NE IS FCST TO EXPAND OVER UPR MI TODAY...AND MOST OF THE MODELS
SHIFT AXIS OF HEAVIER PCPN TO THE N ACCORDINGLY. SO WL EXPAND HIER
POPS NE THRU THE CWA EXCEPT OVER THE KEWEENAW...WHICH WL BE CLOSER
TO THE DEEPER DRY AIR JUST TO THE N. HOWEVER...WITH LINGERING LLVL
DRY AIR...FAVOR THE 00Z REGIONAL CNDN MODEL FCST. THIS MODEL SHOWS
THE HIER QPF REMAINING CLOSER TO THE WI BORDER WHERE EVEN THE 00Z
NAM SHOWS MORE PERSISTENT AXIS OF SHARPER H85-7 FGEN/UVV AND WHERE
PWAT IS FCST TO INCRS TO AOA 1 INCH /ABOUT 225 PCT OF NORMAL/. THIS
FCST IS ALSO MORE CONSISTENT WITH LOCATION OF AXIS OF HEAVIER RA FM
NCENTRAL MN INTO NCENTRAL WI EARLY THIS MRNG...THE LOCATION OF WHICH
MAY HINT AT A BNDRY WHICH MAY ACT TO INTERCEPT MSTR INFLOW. WITH THE
CLDS AND RA DVLPG...EXPECT WELL BLO NORMAL MAX TEMPS THAT WL LIKELY
STAY UNDER 40 AT SOME PLACES NEAR LK SUP.
TNGT...WITH SLOW APRCH OF SHRTWV FM THE WSW TNGT...UPR DVGC OVER AND
MSTR TRANSPORT INTO ARE FCST TO INCRS OVERNGT. SO EXPECT HEAVIER RA
TO EXPAND TO THE NE. THE CNDN MODEL STILL SEEMS TO BE ON THE RIGHT
TRACK SHOWING THE AXIS OF HEAVIER PCPN DIMINISHING A BIT WITH THE
SHIFT TO THE NE GIVEN PERSISTENT DRY AIR IN THAT DIRECTION THAT WILL
TEND TO SHARPEN THE NRN EDGE OF THE PCPN/HEAVIER RA. TOTAL RA THRU
12Z MON WL REACH AS MUCH AS 1.50 TO 2.00 INCHES NEAR THE WI BORDER.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 413 AM EDT SUN APR 24 2016
SHORTWAVE TROUGH LIFTING ACROSS THE NORTHERN PLAINS COMBINES WITH
SHARP H85 BAROCLINIC ZONE TO SUPPORT MODERATE PERHAPS HEAVY RAIN
MONDAY MORNING. SINCE STRONGEST H85 TEMP GRADIENT AND ASSOCIATED
FRONTOGENSIS REMAINS OVER SOUTHERN TIER OF UPR MICHIGAN...PERFER
MODEL SOLUTIONS THAT DIMINISH QPF AS IT LIFTS OVER NORTHERN TIER
OF CWA IN THE MORNING. GFS AND GEM-REGIONAL FIT INTO THAT CATEGORY.
QUITE A COOL AND DAMP DAY ON MON NO MATTER THE COVERAGE OF THE RAIN.
EXPECT CHILLY READINGS IN THE MID-UPR 30S NEAR LK SUPERIOR AND
ONLY AROUND 40 ELSEWHERE.
PRIMARY SHORTWAVE TROUGH ARRIVES OVER UPPER GREAT LAKES ON MONDAY
AFTN. JET STREAK ROUNDING BASE OF TROUGH AND SOME ELEVATED
INSTABILITY MAY RESULT IN TSRA POSSIBLY SNEAKING INTO SCNTRL CWA
LATE MONDAY AFTN INTO MONDAY EVENING. DID KEEP MENTION OF TSRA OUT
ATTM AS WITH SFC LOW PASSING BY SOUTH OF UPR MICHIGAN...WOULD EXPECT
BEST CHANCES FOR EVEN ELEVATED TSRA OVER EASTERN WI AND ON FARTHER
SOUTH. ARRIVAL OF THE SHORTWAVE TROUGH SHOULD BRING ANOTHER ROUND OF
RAIN TO MAINLY THE SOUTH AND SOUTH CENTRAL IN THE AFTN. COOLER AIR
WORKS ACROSS UPR MICHIGAN MON EVENING AS THE LOW OVER WI SLIDES
EAST. 1000-500MB/850-700MB THICKNESSES AND NAM/GFS SOUNDINGS
INDICATE POTENTIAL FOR SNOW TO BEGIN MIXING WITH RAIN OVER HIGHER
TERRAIN OF NW AND NCNTRL MON EVENING THEN SWITCH OVER TO SNOW
OVERNIGHT MON NIGHT. SINCE THE ARRIVAL OF THE COLD AIR TIMES OUT
WITH DIMINISHING PRECIPITATION...SNOW AMOUNTS MON NIGHT SHOULD STAY
LESS THAN AN INCH...MAINLY ON GRASSY SURFACES.
AFTER THE RAIN/SNOW TO SNOW MOVES OUT LATE MON NIGHT...LOOKS DRY
THROUGH THE REST OF THE WEEK AND INTO NEXT WEEKEND AS HIGH PRESSURE
BUILDS OVER HUDSON BAY AND PERSISTS. DRY EASTERLY FLOW SHOULD KEEP
UPPER MICHIGAN DRY. WITH THE EAST TO NORTHEAST WIND OFF THE HIGH
COOLEST READINGS DURING THE DAYTIME SHOULD BE NEAR LK SUPERIOR.
TEMPS THERE LIKELY WILL REMAIN SLIGHTLY BELOW NORMAL THROUGH THE
WEEK. INLAND TEMPS AND NEAR LK MICHIGAN SHOULD REACH TOWARD NORMAL
BY MID TO LATE WEEK WITH READINGS IN THE 50S TO NEAR 60 BY LATE IN
THE WEEK. INFLUENCE OF THE DRY HIGH PRESSURE SHOULD ALLOW TEMPS AT
NIGHT AWAY FROM THE GREAT LAKES TO FALL INTO THE 20S TO LOW 30S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 121 AM EDT SUN APR 24 2016
VFR CONDITIONS WILL HOLD ON UNTIL LATE TONIGHT AT ALL SITES UNDER
MID LEVEL CLOUDS. LIGHT RAIN WILL ARRIVE AND WILL CONTINUE THROUGH
THE REST OF THE FORECAST PERIOD. ONCE THE RAIN ARRIVES...CIGS WILL
STEADILY LOWER...REACHING IFR AT ALL TERMINALS AFTER 12Z. CONDITIONS
SHOULD CONTINUE TO DETERIORATE FURTHER TO LIFR/VLIFR DURING THE
MORNING HRS AND WILL CONTINUE THAT WAY THE REST OF THE FORECAST
PERIOD AT ALL SITES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 AM EDT SUN APR 24 2016
WITH TIGHTENING PRES GRADIENT BETWEEN HI PRES BUILDING INTO NORTHERN
ONTARIO AND A LO PRES MOVING E FROM THE PLAINS ALONG A STALLED LO
PRES TROUGH TO THE S...EXPECT NE WINDS INCREASING TO 25 TO 30 KTS
THRU MON. THE STRONGEST WINDS WILL BE OVER THE WESTERN LAKE...WHERE
GALES TO 35-40 KTS ARE FORECAST THIS AFTERNOON THRU MON WITH A
COASTLINE CONFIGURATION THAT WILL ACCENTUATE THE NE FLOW. EXPANDED
THE GALE WARNING FOR LSZ162 TO INCLUDE LSZ263 FOR LATE TONIGHT AND
MON. WINDS WILL GRADUALLY DIMINISH MON NIGHT THRU TUE AS A HI PRES
BUILDS INTO THE UPPER LAKES. N TO E WINDS GENERALLY UNDER 20 KTS WILL
THEN PREVAIL ON WED AND THU WITH A HI PRES RIDGE AXIS IN PLACE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 11 AM EDT /10 AM CDT/ THIS MORNING TO 8 PM EDT
/7 PM CDT/ MONDAY FOR LSZ162.
GALE WARNING FROM 5 AM TO 8 PM EDT MONDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...07
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
413 AM EDT SUN APR 24 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 424 PM EDT SAT APR 23 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW SPLIT FLOW OVER NAMERICA.
IN THE NRN STREAM...A TROF EXTENDS THRU HUDSON BAY INTO SE CANADA
BTWN RIDGING OVER WRN CANADA AND A CLOSED MID LEVEL HIGH CENTERED
JUST SE OF GREENLAND. IN THE SRN STREAM...A TROF IS OVER THE WRN
CONUS WITH RIDGING OUT OVER THE PLAINS. JET STREAK DEVELOPING IN THE
CONFLUENCE BTWN THE SRN STREAM RIDGE AND NRN STREAM TROF OVER SE
CANADA WILL BE ONE OF THE MAIN PLAYERS IN THE WET WEATHER SETTING UP
ACROSS UPPER MI FOR THE NEXT 36-48HRS. WELL OUT AHEAD OF THE WRN
CONUS TROF...WAA/ISENTROPIC ASCENT REGIME SRPEADING OVER THE NRN
PLAINS HAS LED TO SCT -SHRA DEVELOPMENT FROM ND ACROSS NE MN
THIS AFTN. MID CLOUDS ARE PEELING SE FROM THAT AREA ACROSS UPPER MI.
ALTHOUGH CLOUDS HAVE WORKED TO SOMEWHAT LIMIT THE NORMAL DIURNAL
BUILDING OF MIXING HEIGHTS...SFC DWPTS HAVE STILL FALLEN DOWN INTO
THE SINGLE DIGITS/LOW TEENS ACROSS PORTIONS OF INTERIOR W AND CNTRL
UPPER MI.
A GOOD PATTERN FOR SOAKING RAINS WILL BE SETTING UP ACROSS THE AREA
OVER THE NEXT 36-48HRS AS FCST AREA WILL RESIDE IN A SHARP
BAROCLINIC ZONE RESULTING FROM COLD AIR SPREADING ACROSS SE CANADA
UNDER NRN STREAM TROF AND WARM AIR PUSHING TOWARD THE UPPER
MISSISSIPPI VALLEY AHEAD OF THE SRN STREAM WRN CONUS TROF. IN
FACT...MOST OF THE FCST AREA WILL SEE MDT TO HVY RAINFALL AMOUNTS BY
THE TIME THIS WET PERIOD WRAPS UP MON NIGHT. AFOREMENTIONED JET
STREAK WILL BE A KEY MECHANISM FOR PCPN GENERATION AS THE RIGHT
ENTRANCE WILL PROVIDE LARGER SCALE UPPER DIVERGENCE OVER THE AREA.
AT THE LOWER LEVELS...850MB FRONT SETTING UP IN THE VCNTY OF THE
MI/WI BORDER WILL PROVIDE A FOCUS FOR PCPN DEVELOPMENT UNDER
PERSISTENT FGEN/ISENTROPIC ASCENT. PRECIPITABLE WATER INCREASING TO
AROUND 1 INCH (200-250PCT OF NORMAL) WILL THEN SUPPORT THE EXPECTED
MDT/HVY PCPN AMOUNTS. UTILIZED A MIX OF ALL AVBL MODELS TO CONSTRUCT
POPS/PCPN AMOUNTS FOR TONIGHT/SUN AS MOST OF THE GUIDANCE IS FAIRLY
WELL CLUSTERED ON QPF AND TIMING ONSET OF RAIN. PCPN DEVELOPMENT
TONIGHT MAY BE DELAYED MORE SO THAN REFLECTED IN FCST DUE TO THE
VERY DRY AIR OVER THE AREA ATTM. BY 00Z MON...EXPECT PCPN AMOUNTS
RANGING FROM AROUND ONE-THIRD OF AN INCH OVER THE NRN KEWEENAW
PENINSULA AND NE LUCE COUNTY TO 0.90-1.25 INCHES OVER MUCH OF THE W
AND CNTRL FCST AREA. AS FOR TEMPS...LOWS TONIGHT SHOULD RANGE FROM
THE MID 30S TO LWR 40S...WARMEST FAR W. WITH EXPECTATION OF RAIN
PREVAILING FOR MUCH OF THE DAY IN MOST AREAS...LOWERED MAX TEMPS
SOME FOR SUN. HIGHS SHOULD RANGE FROM THE UPPER 30S NW AND NCNTRL TO
MAINLY THE LWR 40S ELSEWHERE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 413 AM EDT SUN APR 24 2016
SHORTWAVE TROUGH LIFTING ACROSS THE NORTHERN PLAINS COMBINES WITH
SHARP H85 BAROCLINIC ZONE TO SUPPORT MODERATE PERHAPS HEAVY RAIN
MONDAY MORNING. SINCE STRONGEST H85 TEMP GRADIENT AND ASSOCIATED
FRONTOGENSIS REMAINS OVER SOUTHERN TIER OF UPR MICHIGAN...PERFER
MODEL SOLUTIONS THAT DIMINISH QPF AS IT LIFTS OVER NORTHERN TIER
OF CWA IN THE MORNING. GFS AND GEM-REGIONAL FIT INTO THAT CATEGORY.
QUITE A COOL AND DAMP DAY ON MON NO MATTER THE COVERAGE OF THE RAIN.
EXPECT CHILLY READINGS IN THE MID-UPR 30S NEAR LK SUPERIOR AND
ONLY AROUND 40 ELSEWHERE.
PRIMARY SHORTWAVE TROUGH ARRIVES OVER UPPER GREAT LAKES ON MONDAY
AFTN. JET STREAK ROUNDING BASE OF TROUGH AND SOME ELEVATED
INSTABILITY MAY RESULT IN TSRA POSSIBLY SNEAKING INTO SCNTRL CWA
LATE MONDAY AFTN INTO MONDAY EVENING. DID KEEP MENTION OF TSRA OUT
ATTM AS WITH SFC LOW PASSING BY SOUTH OF UPR MICHIGAN...WOULD EXPECT
BEST CHANCES FOR EVEN ELEVATED TSRA OVER EASTERN WI AND ON FARTHER
SOUTH. ARRIVAL OF THE SHORTWAVE TROUGH SHOULD BRING ANOTHER ROUND OF
RAIN TO MAINLY THE SOUTH AND SOUTH CENTRAL IN THE AFTN. COOLER AIR
WORKS ACROSS UPR MICHIGAN MON EVENING AS THE LOW OVER WI SLIDES
EAST. 1000-500MB/850-700MB THICKNESSES AND NAM/GFS SOUNDINGS
INDICATE POTENTIAL FOR SNOW TO BEGIN MIXING WITH RAIN OVER HIGHER
TERRAIN OF NW AND NCNTRL MON EVENING THEN SWITCH OVER TO SNOW
OVERNIGHT MON NIGHT. SINCE THE ARRIVAL OF THE COLD AIR TIMES OUT
WITH DIMINISHING PRECIPITATION...SNOW AMOUNTS MON NIGHT SHOULD STAY
LESS THAN AN INCH...MAINLY ON GRASSY SURFACES.
AFTER THE RAIN/SNOW TO SNOW MOVES OUT LATE MON NIGHT...LOOKS DRY
THROUGH THE REST OF THE WEEK AND INTO NEXT WEEKEND AS HIGH PRESSURE
BUILDS OVER HUDSON BAY AND PERSISTS. DRY EASTERLY FLOW SHOULD KEEP
UPPER MICHIGAN DRY. WITH THE EAST TO NORTHEAST WIND OFF THE HIGH
COOLEST READINGS DURING THE DAYTIME SHOULD BE NEAR LK SUPERIOR.
TEMPS THERE LIKELY WILL REMAIN SLIGHTLY BELOW NORMAL THROUGH THE
WEEK. INLAND TEMPS AND NEAR LK MICHIGAN SHOULD REACH TOWARD NORMAL
BY MID TO LATE WEEK WITH READINGS IN THE 50S TO NEAR 60 BY LATE IN
THE WEEK. INFLUENCE OF THE DRY HIGH PRESSURE SHOULD ALLOW TEMPS AT
NIGHT AWAY FROM THE GREAT LAKES TO FALL INTO THE 20S TO LOW 30S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 121 AM EDT SUN APR 24 2016
VFR CONDITIONS WILL HOLD ON UNTIL LATE TONIGHT AT ALL SITES UNDER
MID LEVEL CLOUDS. LIGHT RAIN WILL ARRIVE AND WILL CONTINUE THROUGH
THE REST OF THE FORECAST PERIOD. ONCE THE RAIN ARRIVES...CIGS WILL
STEADILY LOWER...REACHING IFR AT ALL TERMINALS AFTER 12Z. CONDITIONS
SHOULD CONTINUE TO DETERIORATE FURTHER TO LIFR/VLIFR DURING THE
MORNING HRS AND WILL CONTINUE THAT WAY THE REST OF THE FORECAST
PERIOD AT ALL SITES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 PM EDT SAT APR 23 2016
A CLASSIC SET UP FOR BRISK E TO NE WINDS IS SHAPING UP FOR LAKE
SUPERIOR OVER THE NEXT COUPLE OF DAYS AS HIGH PRES BUILDS INTO
NORTHERN ONTARIO AND A WEAK LOW PRES WAVE TRACKS ALONG A FRONT S OF
UPPER MI. WINDS INITIALLY UNDER 20KT THIS EVENING WILL SLOWLY RAMP
UP TONIGHT...MAINLY OVER WESTERN LAKE SUPERIOR. WINDS THEN INCREASE
MORE NOTABLY ACROSS THE LAKE SUN THRU MON MORNING...REACHING GALES
OVER FAR WESTERN LAKE SUPERIOR LATE SUN MORNING THRU MON AFTN AS
COASTAL CONVERGENCE/FUNNELING ENHANCE THE WINDS IN THAT AREA. A GALE
WARNING HAS BEEN POSTED FOR THAT PART OF THE LAKE. ACROSS THE REST
OF LAKE SUPERIOR...WINDS WILL INCREASE TO 20-30KT. WINDS WILL SLOWLY
DIMINISH MON NIGHT/TUE MORNING...BUT MORE SO TUE AFTN/NIGHT AS THE
NORTHERN ONTARIO HIGH PRES BUILDS INTO THE UPPER LAKES. E TO NE
WINDS GENERALLY UNDER 20KT WILL PREVAIL WED/THU. GIVEN THE E TO NE
WIND DIRECTION...WINDS WILL BE STRONGEST OVER WRN LAKE SUPERIOR ON
BOTH OF THOSE DAYS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 11 AM EDT /10 AM CDT/ THIS MORNING TO 8 PM EDT
/7 PM CDT/ MONDAY FOR LSZ162.
GALE WARNING FROM 5 AM TO 8 PM EDT MONDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
122 AM EDT SUN APR 24 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 424 PM EDT SAT APR 23 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW SPLIT FLOW OVER NAMERICA.
IN THE NRN STREAM...A TROF EXTENDS THRU HUDSON BAY INTO SE CANADA
BTWN RIDGING OVER WRN CANADA AND A CLOSED MID LEVEL HIGH CENTERED
JUST SE OF GREENLAND. IN THE SRN STREAM...A TROF IS OVER THE WRN
CONUS WITH RIDGING OUT OVER THE PLAINS. JET STREAK DEVELOPING IN THE
CONFLUENCE BTWN THE SRN STREAM RIDGE AND NRN STREAM TROF OVER SE
CANADA WILL BE ONE OF THE MAIN PLAYERS IN THE WET WEATHER SETTING UP
ACROSS UPPER MI FOR THE NEXT 36-48HRS. WELL OUT AHEAD OF THE WRN
CONUS TROF...WAA/ISENTROPIC ASCENT REGIME SRPEADING OVER THE NRN
PLAINS HAS LED TO SCT -SHRA DEVELOPMENT FROM ND ACROSS NE MN
THIS AFTN. MID CLOUDS ARE PEELING SE FROM THAT AREA ACROSS UPPER MI.
ALTHOUGH CLOUDS HAVE WORKED TO SOMEWHAT LIMIT THE NORMAL DIURNAL
BUILDING OF MIXING HEIGHTS...SFC DWPTS HAVE STILL FALLEN DOWN INTO
THE SINGLE DIGITS/LOW TEENS ACROSS PORTIONS OF INTERIOR W AND CNTRL
UPPER MI.
A GOOD PATTERN FOR SOAKING RAINS WILL BE SETTING UP ACROSS THE AREA
OVER THE NEXT 36-48HRS AS FCST AREA WILL RESIDE IN A SHARP
BAROCLINIC ZONE RESULTING FROM COLD AIR SPREADING ACROSS SE CANADA
UNDER NRN STREAM TROF AND WARM AIR PUSHING TOWARD THE UPPER
MISSISSIPPI VALLEY AHEAD OF THE SRN STREAM WRN CONUS TROF. IN
FACT...MOST OF THE FCST AREA WILL SEE MDT TO HVY RAINFALL AMOUNTS BY
THE TIME THIS WET PERIOD WRAPS UP MON NIGHT. AFOREMENTIONED JET
STREAK WILL BE A KEY MECHANISM FOR PCPN GENERATION AS THE RIGHT
ENTRANCE WILL PROVIDE LARGER SCALE UPPER DIVERGENCE OVER THE AREA.
AT THE LOWER LEVELS...850MB FRONT SETTING UP IN THE VCNTY OF THE
MI/WI BORDER WILL PROVIDE A FOCUS FOR PCPN DEVELOPMENT UNDER
PERSISTENT FGEN/ISENTROPIC ASCENT. PRECIPITABLE WATER INCREASING TO
AROUND 1 INCH (200-250PCT OF NORMAL) WILL THEN SUPPORT THE EXPECTED
MDT/HVY PCPN AMOUNTS. UTILIZED A MIX OF ALL AVBL MODELS TO CONSTRUCT
POPS/PCPN AMOUNTS FOR TONIGHT/SUN AS MOST OF THE GUIDANCE IS FAIRLY
WELL CLUSTERED ON QPF AND TIMING ONSET OF RAIN. PCPN DEVELOPMENT
TONIGHT MAY BE DELAYED MORE SO THAN REFLECTED IN FCST DUE TO THE
VERY DRY AIR OVER THE AREA ATTM. BY 00Z MON...EXPECT PCPN AMOUNTS
RANGING FROM AROUND ONE-THIRD OF AN INCH OVER THE NRN KEWEENAW
PENINSULA AND NE LUCE COUNTY TO 0.90-1.25 INCHES OVER MUCH OF THE W
AND CNTRL FCST AREA. AS FOR TEMPS...LOWS TONIGHT SHOULD RANGE FROM
THE MID 30S TO LWR 40S...WARMEST FAR W. WITH EXPECTATION OF RAIN
PREVAILING FOR MUCH OF THE DAY IN MOST AREAS...LOWERED MAX TEMPS
SOME FOR SUN. HIGHS SHOULD RANGE FROM THE UPPER 30S NW AND NCNTRL TO
MAINLY THE LWR 40S ELSEWHERE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 511 PM EDT SAT APR 23 2016
COOL CONDITIONS ARE EXPECTED THROUGH THE UPCOMING WEEK...WITH HEAVY
RAIN EXPECTED THROUGH MONDAY.
SUNDAY NIGHT AND MONDAY NIGHT...A STOUT BAROCLINIC ZONE STRETCHING
FROM THE NORTHERN PLAINS TO THE LOWER GREAT LAKES WILL BE THE FOCUS
FOR AN ONGOING ACTIVE PERIOD OF WEATHER. SUBSTANTIAL LOW TO MID-
LEVEL FGEN...WAA...AND LOW-LEVEL MOISTURE TRANSPORT WILL BRING A
CONTINUOUS FEED OF PRECIP ACROSS THE CWA THROUGH AT LEAST MONDAY
MORNING. PWATS APPROACHING 1.5 INCHES ACROSS MN TRACKING TOWARD THE
AREA IN CONJUNCTION WITH AN APPROACHING RIGHT ENTRANCE TO AN UPPER
JET WILL SUPPORT A PERIOD OF MODERATE TO HEAVY RAIN ACROSS ALL BUT
THE KEWEENAW PENINSULA SUNDAY EVENING INTO THE OVERNIGHT HOURS.
MODEL QPF SUNDAY NIGHT ADVERTISES A STRIPE OF 1 TO 2 INCHES WITH
ISOLATED 3 INCH TOTALS ACROSS THE CWA. CURRENT THINKING PUTS THE
HEAVIEST RAIN ALONG A LINE FROM FAR NW WI TO NORTHERN LAKE
MI...INCLUDING IWD...IMT...AND ESC. HOWEVER...MODEL GUIDANCE
CONTINUES TO TREND NORTHWARD WITH THIS SET-UP. IN FACT...LAST
WEEK...LONG TERM GUIDANCE PLACED ALL OF UPPER MI ON THE COLD AND DRY
SIDE OF THE BAROCLINIC ZONE. GIVEN THE MODEL TRENDS...HAVE CONTINUED
THE NORTHWARD PROGRESSION OF THE HIGHEST QPF SUNDAY NIGHT.
AS THE LOW-LEVEL SYSTEM PASSES TO THE SOUTH ON MONDAY...MID-LEVEL
FGEN WILL BE ENHANCED ACROSS THE CWA. THIS WILL FAVOR CONTINUED
MODERATE RAINFALL THROUGH THE MORNING AND POSSIBLY INTO THE
AFTERNOON ACROSS THE SOUTH HALF OF THE CWA. WEAKER FORCING AND DRIER
AIR FILTERING ACROSS THE AREA MONDAY AFTERNOON INTO MONDAY NIGHT
WILL ALLOW FOR A GRADUAL DIMINISHING TREND IN PRECIP AND CLOUD COVER
FROM NORTH TO SOUTH.
WITH THE NORTHWARD TREND IN MODEL GUIDANCE...THE PROSPECTS OF
APPRECIABLE ACCUMULATING SNOW CONTINUE TO DIMINISH. FORECAST
SOUNDINGS INDICATE SLIGHTLY ABOVE FREEZING TEMPS ACROSS THE CWA
THROUGH SUNDAY NIGHT. AS DRYING AND SOME COLDER AIR WORK IN FROM THE
NORTH ON MONDAY...PRECIP MAY SWITCH OVER TO SNOW ACROSS THE HIGH
TERRAIN OF THE NORTH. HOWEVER...WITH A BULK OF THE PRECIP OVER...AND
WITH LATE APRIL DAYTIME HEATING PRESENT...DO NOT EXPECT ANYTHING
MORE THAN UP TO A SLUSHY INCH OF ACCUMULATION ON GRASSY SURFACES
DURING THE DAY.
FORECAST STORM TOTAL QPF TONIGHT THROUGH MONDAY PLACES A SWATH OF 2
TO 3 INCHES SOUTH OF A LINE FROM ONTONAGON TO MARQUETTE TO ST
IGNACE. AMOUNTS QUICKLY DROP OFF TO THE NORTH...WITH LESS THAN A
HALF INCH EXPECTED FOR COPPER HARBOR. GIVEN THE WIDE VARIETY OF QPF
PLACEMENT AMONG MODELS AND ENSEMBLES...IT MUST BE NOTED THAT
LOCALIZED AMOUNTS IN EXCESS OF 4 INCHES WILL BE POSSIBLE THROUGH THE
AFOREMENTIONED PERIOD. GIVEN THE RECENT DRY PERIOD...FLOODING
CONCERNS ARE SOMEWHAT EASED. HOWEVER...WITH LITTLE TO NO
GREENUP...SOILS WILL BECOME SATURATED QUICKLY. HAVE DECIDED TO ISSUE
AN SPS TO ACCOUNT FOR POTENTIALLY VERY HEAVY RAIN AND ELEVATED RIVER
LEVELS THROUGH THE UPCOMING WEEK.
FOR THE REMAINDER OF THE WEEK...COOL AND MOSTLY DRY CONDITIONS WILL
PREVAIL AS HIGH PRESSURE RIDGING EDGES FROM NORTHERN ONTARIO INTO
THE UPPER GREAT LAKES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 121 AM EDT SUN APR 24 2016
VFR CONDITIONS WILL HOLD ON UNTIL LATE TONIGHT AT ALL SITES UNDER
MID LEVEL CLOUDS. LIGHT RAIN WILL ARRIVE AND WILL CONTINUE THROUGH
THE REST OF THE FORECAST PERIOD. ONCE THE RAIN ARRIVES...CIGS WILL
STEADILY LOWER...REACHING IFR AT ALL TERMINALS AFTER 12Z. CONDITIONS
SHOULD CONTINUE TO DETERIORATE FURTHER TO LIFR/VLIFR DURING THE
MORNING HRS AND WILL CONTINUE THAT WAY THE REST OF THE FORECAST
PERIOD AT ALL SITES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 PM EDT SAT APR 23 2016
A CLASSIC SET UP FOR BRISK E TO NE WINDS IS SHAPING UP FOR LAKE
SUPERIOR OVER THE NEXT COUPLE OF DAYS AS HIGH PRES BUILDS INTO
NORTHERN ONTARIO AND A WEAK LOW PRES WAVE TRACKS ALONG A FRONT S OF
UPPER MI. WINDS INITIALLY UNDER 20KT THIS EVENING WILL SLOWLY RAMP
UP TONIGHT...MAINLY OVER WESTERN LAKE SUPERIOR. WINDS THEN INCREASE
MORE NOTABLY ACROSS THE LAKE SUN THRU MON MORNING...REACHING GALES
OVER FAR WESTERN LAKE SUPERIOR LATE SUN MORNING THRU MON AFTN AS
COASTAL CONVERGENCE/FUNNELING ENHANCE THE WINDS IN THAT AREA. A GALE
WARNING HAS BEEN POSTED FOR THAT PART OF THE LAKE. ACROSS THE REST
OF LAKE SUPERIOR...WINDS WILL INCREASE TO 20-30KT. WINDS WILL SLOWLY
DIMINISH MON NIGHT/TUE MORNING...BUT MORE SO TUE AFTN/NIGHT AS THE
NORTHERN ONTARIO HIGH PRES BUILDS INTO THE UPPER LAKES. E TO NE
WINDS GENERALLY UNDER 20KT WILL PREVAIL WED/THU. GIVEN THE E TO NE
WIND DIRECTION...WINDS WILL BE STRONGEST OVER WRN LAKE SUPERIOR ON
BOTH OF THOSE DAYS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 11 AM EDT /10 AM CDT/ THIS MORNING TO 8 PM EDT
/7 PM CDT/ MONDAY FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KLUBER
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
348 PM CDT SUN APR 24 2016
.SHORT TERM...(TONIGHT)
ISSUED AT 348 PM CDT SUN APR 24 2016
A STRONG LOW PRESSURE SYSTEM WAS OVER CENTRAL SOUTH DAKOTA AT MID
AFTERNOON. A NEARLY STATIONARY FRONT MEANDERED FROM THE LOW
THROUGH WEST CENTRAL MN TO THE SOUTHERN METRO TO SOUTH OF EAU
CLAIRE WHILE A COLD FRONT CURVED SOUTH FROM THE LOW THROUGH
EASTERN NEBRASKA. SOME SUNSHINE DID OCCUR EARLIER IN THE
AFTERNOON ACROSS SOUTHWEST MN THROUGH EASTERN NE AND WESTERN IA.
THIS AREA HAS BECOME QUITE UNSTABLE WITH STORM DEVELOPMENT ALREADY
IN PROGRESS ACROSS EASTERN NE. VARIOUS CAMS INDICATE FURTHER
STRENGTHENING OF THE STORMS IN EASTERN NE WHILE MOVING INTO NW IA
AND EVENTUALLY SOUTHWEST AND SOUTH CENTRAL MN THIS EVENING.
EFFECTIVE SHEAR IS BEST INTO EARLY THIS EVENING ACROSS OUR FAR
WEST CENTRAL AND SOUTHWEST MN COUNTIES. HENCE...A SEVERE STORM OR
TWO CAN NOT BE RULED OUT TO THE NORTH AND EAST OF THE CURRENT
SEVERE THUNDERSTORM WATCH WHICH ADJOINS OUR SOUTHWEST MN CWA.
CAPE BEGINS TO FADE QUICKLY AFTER 02Z ON THE HRRR WITH A DOWNWARD
TREND IN STORM INTENSITY EXPECTED. THE STORMS COULD BE GETTING
CLOSE TO THE SOUTHWEST METRO AT THAT TIME BUT IN A WEAKENING MODE.
SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE THROUGH THE NIGHT
AS THE LOW SLOWLY APPROACHES SOUTHWEST MN BY DAYBREAK MONDAY. THE
SHOWERS AND THUNDERSTORMS WILL BE EFFICIENT RAIN PRODUCERS. PW
VALUES WILL PEAK AROUND 1.4 INCHES ACROSS SOUTH CENTRAL MN THIS
EVENING WITH VALUES ELSEWHERE IN THE 1.2 TO 1.3 INCH RANGE. THIS
IS AT THE TOP OF OUR PW CLIMATOLOGY FOR LATE APRIL. THEREFORE A
QUICK INCH OF RAIN IS NOT OUT OF THE QUESTION. QPF GRIDS ARE
WIDESPREAD HALF TO ONE INCH. THERE WILL ALSO BE QUITE THE THERMAL
CONTRAST ACROSS THE FA OVERNIGHT WITH THE EAST- WEST BOUNDARY
ACROSS SOUTHERN MN. LOWS WILL RANGE FROM THE LOWER 40S ACROSS
CENTRAL MN TO NEAR 60 AT ALBERT LEA.
.LONG TERM...(MONDAY THROUGH SUNDAY)
ISSUED AT 348 PM CDT SUN APR 24 2016
AN ACTIVE SOUTHWEST FLOW PATTERN WILL BE IN PLACE THROUGH THE
WEEKEND ACROSS THE CENTRAL CONUS. THE RESULT WILL BE A WET AND
SOMEWHAT COOL PATTERN OVER THE NEXT 7 DAYS.
THE FIRST OF THREE ROBUST UPPER LOWS WILL PASS ACROSS MN AND INTO
WISCONSIN TOMORROW. AS MENTIONED IN THE DISCUSSION ABOVE...THUNDER
IS EXPECTED TONIGHT OUT AHEAD OF THIS LOW THAT IS ADVANCING ACROSS
THE DAKOTAS. TOMORROW THE UPPER LOW WILL PASS ACROSS MN BUT START
TO SHEAR OUT AS IT REACHES LAKE SUPERIOR TOMORROW NIGHT. THE SURFACE
LOW WILL TRACK JUST TO THE SOUTH FROM ROUGHLY REDWOOD FALLS...TO
SOMEWHERE BETWEEN MANKATO AND THE SOUTHERN TWIN CITES METRO...TO
AROUND LA CROSSE. THE WARM FRONT ASSOCIATED WITH THIS LOW WILL
BISECT THE FORECAST AREA AND ONCE AGAIN YIELD A PRONOUNCED NORTH-
SOUTH TEMPERATURE GRADIENT ACROSS MN AND WESTERN WI. THERE WILL
ONCE AGAIN BE WIDESPREAD SHOWERS ACROSS THE FORECAST AREA WITH THE
POTENTIAL FOR THUNDER ACROSS EASTERN MN AND WESTERN WI WHERE
FORECAST SOUNDINGS SHOW 200-800J/KG OF MUCAPE AND ENOUGH VERTICAL
WIND SHEAR TO SUPPORT WEAKLY ORGANIZED OR MULTICELL CONVECTION. A
STRONG CELL OR TWO CANNOT BE RULED OUT TOMORROW AFTERNOON IN
WI...ESPECIALLY GIVEN THE WARM FRONT IN THE VICINITY AND THE ADDED
VORTICITY DUE TO THE SURFACE LOW. IT SORT OF HAS THE LOOK OF A
LOW- TOPPED NON-SUPERCELL LANDSPOUT DAY.
THERE IS ANOTHER DEEP LOW EJECTING OUT OFF THE ROCKIES AND INTO THE
PLAINS ON TUESDAY. THE TROUGH WILL DIG IN A LITTLER FARTHER SOUTH
AND WRAP MUCH MORE MOISTURE NORTH ACROSS THE PLAINS. THIS IS SETTING
THE STAGE FOR SEVERE WEATHER IN STATES TO OUR SOUTH.
LOCALLY...WIDESPREAD MODERATE RAIN TO POTENTIALLY HEAVY RAIN AS THE
LOW SWINGS EAST/NORTHEAST AND MID-LEVEL FGEN TRANSLATES ACROSS THE
AREA. A THIRD TROUGH WILL MAKE ITS WAY INTO THE CENTRAL CONUS THIS
WEEKEND AND CONTINUES OUR CHANCE FOR SHOWERS AND STORMS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1237 PM CDT SUN APR 24 2016
A NEARLY STATIONARY FRONT STRETCHES FROM WEST CENTRAL MN THROUGH
THE SOUTH METRO TO SOUTH OF KEAU. THE BOUNDARY WILL SLIP SLOWLY
SOUTH THIS EVENING ALLOWING MVFR OR LOWER CEILINGS TO SETTLE
ACROSS ALL OF CENTRAL MN AND MUCH OF WEST CENTRAL WI. THE METRO
AREA WILL BE BORDERLINE THIS EVENING THEN TREND LOWER OVERNIGHT.
SHOWERS CHANCES EARLY THIS AFTERNOON WILL BE MOST NUMEROUS ACROSS
CENTRAL MN AND WEST CENTRAL WI WITH MORE ROBUST THUNDERSTORMS
DEVELOPING ACROSS WEST CENTRAL THROUGH SOUTH CENTRAL MN LATE IN
THE DAY AND PROGRESSING EASTWARD THIS EVENING. THE THUNDERSTORM
ACTIVITY WILL LIKELY WANE OVERNIGHT AND TURN INTO A LARGE AREA OF
SHOWERS/LIGHT RAIN WITH LESS THAN MVFR VISIBILITIES. MVFR OR LOWER
CEILINGS AND VISIBILITIES WILL OCCUR ON MONDAY ALONG WITH SHOWERS
AND ISOLATED THUNDERSTORMS AS A LOW PRESSURE SYSTEM MOVES SLOWLY
EASTWARD ACROSS THE TAF SITES. WINDS THIS AFTERNOON AND EVENING
WILL BE ENE AT 15-20 KNOTS NORTH OF THE BOUNDARY AND SSE 15-25
KNOTS SOUTH OF THE BOUNDARY. WIND SPEEDS WILL SLOWLY DIMINISH
TONIGHT.
KMSP...A FEW SHOWERS EARLY THIS AFTERNOON WITH MAINLY VFR
CONDITIONS. THUNDERSTORMS CHANCES LOOK HIGH THIS EVENING WITH A
TEMPO GROUP INSERTED. THEREAFTER...SHOWERS WILL DIMINISH FOR A
TIME BUT THEM PICK BACK UP LATE IN THE NIGHT AND FOR EARLY
MONDAY WITH IFR CONDITIONS LIKELY.
/OUTLOOK FOR KMSP/
MON...MVFR/IFR WITH -SHRA ISOLATED TSRA. WIND NE 10-15KTS.
TUE...VFR. WINDS E 10-15KTS.
WED...MVFR LATE IN THE DAY. SHRA LIKELY. WIND E 15-25KTS
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...RAH
LONG TERM...CLF
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1242 PM CDT SUN APR 24 2016
.UPDATE...
ISSUED AT 1235 PM CDT SUN APR 24 2016
PARAMETERS ARE STILL COMING TOGETHER FOR A THREAT OF SEVERE THIS
AFTERNOON. AREA OF MID AND UPPER 50S DEW POINTS WERE BEGINNING TO
SURGE NORTH INTO WESTERN SECTIONS OF EASTERN NEBRASKA AS OF
NOON...JUST EAST OF DRYLINE IN CENTRAL NEBRASKA. SCATTERED SHOWERS
HAVE PERSISTED IN MID LEVEL WARM ADVECTION THERE...BUT CLEARING TO
THE EAST WAS NOTED ON VISIBLE SATELLITE LOOPS. THIS WAS ALLOWING
TEMPERATURES TO CLIMB INTO THE 70S. WHERE MOISTURE AND WARMING WERE
COINCIDENT IN CENTRAL KANSAS...SURFACE-BASED CAPES WERE ALREADY
TOPPING 1000 J/KG. AND WITH CONTINUED WARMING/MOISTENING...EXPECT AT
LEAST 1500 J/KG JUST AHEAD OF DRYLINE LATER THIS AFTERNOON IN
EASTERN NEBRASKA. BULK SHEAR WAS INCREASING AS EXPECTED AS
WELL...WITH 0-6KM VECTORS SOUTHWEST AT 30KT AS OF NOON. A
CONSENSUS OF HI-RES CONVECTION-ALLOWING MODELS SUGGESTS
INITIATION WILL OCCUR SOMETIME NEAR OR JUST AFTER 21Z...LIKELY
ALONG A WAYNE TO JUST WEST OF LINCOLN LINE AS PER EXPERIMENTAL
HRRR OUTPUT. GIVEN EXPECTED INSTABILITY AND SHEAR VECTORS BECOMING
MORE NORMAL TO LINE OF CONVECTION...SUPERCELL STRUCTURES ARE
LIKELY WITH ATTENDANT LARGE HAIL AND DAMAGING WIND THREAT. THERE
IS ALSO A SMALL TORNADO RISK...ESPECIALLY IN SOUTHEAST NEBRASKA AT
LATE AFTERNOON WHERE AXIS OF HIGHER HELICITY NOSES IN FROM THE
SOUTH.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 315 AM CDT SUN APR 24 2016
THE POTENTIAL FOR SEVERE STORMS TODAY IS THE MAIN FCST CONCERN.
CLOSED LOW AT 500 MB WAS NEAR THE UT/WY/CO BORDER AREA AT 00Z WITH
12 HOUR HEIGHT FALLS OF UP TO AROUND 80 METERS JUST AHEAD OF THE
CIRCULATION CENTER. THERE WAS A JET SEGMENT OF AROUND 70 KTS AT
300 MB NEAR THE UT/CO BORDER. AT 700 MB...THERMAL RIDGE AXIS
STRETCHED FROM SWRN NM UP INTO SERN MT. MOIST AXIS AT 850 MB
EXTENDED FROM TX INTO THE DKTS. WATER VAPOR STLT IMAGERY EARLY
THIS MORNING SHOWED THE MID TROPOSPHERIC LOW HAD PROGRESSED INTO
CENTRAL WY. SFC ANLYS AT 08Z HAD A LOW PRES CENTER OVER WRN SD.
A WMFNT EXTENDED E/NE FROM THE LOW INTO MN AND A CDFNT EXTENDED
S/SW INTO NERN NM. DEWPOINTS AHEAD OF THE CDFNT WERE IN THE UPPER
40S AND LOWER 50S.
TODAY...CURRENT SHOWERS AND TSTMS TO OUR WEST SHOULD MOVE INTO
THE AREA THIS MORNING BUT IT APPEARS THESE WILL STAY BELOW SVR
LIMITS. RECENT RUNS OF THE RAP AND HRRR MODELS DEPICT VIGOROUS
STORM DEVELOPMENT IN OUR AREA THIS AFTN. SFC-500 METER MIXED
LAYER CAPE VALUES COULD REACH AROUND 2000 J/KG BY MID AFTN IN OUR
WRN ZONES...BASED ON DEWPOINTS RISING TO THE MID/UPPER 50S. THE
STRONGEST STORMS SHOULD FORM THERE AND THEN DVLP EWD. ZERO TO 6 KM
SHEAR VALUES OF 35-45 KTS SHOULD BE ENOUGH FOR SOME SUPERCELLS...
WITH HAIL THE MOST LIKELY HAZARD. EXPERIMENTAL HRRR AND MANY OTHER
CONVECTION ALLOWING MODELS SHOW SIMILAR RESULTS. LOOK FOR HIGHS 75
TO 80.
STORMS SHOULD CONTINUE TO DVLP EWD AND MAINLY BE OUT OF THE AREA
BY 06Z TNGT. SOME SMALL CHANCE OF SHOWERS MAY LINGER INTO THE
EARLY MORNING HOURS...MAINLY NEAR THE SD BORDER. SFC LOW SHOULD BE
JUST NW OF KSUX BY 12Z MON...THEN THAT WILL MOVE TO NEAR THE
WI/IA/MN BORDER AREA BY 00Z TUE. NW SFC WINDS SHOULD PULL COOLER
AIR INTO NERN NE FOR MON...BUT COOLING WILL BE LESS FOR SERN NE
AND SWRN IA. THERE COULD BE SOME LGT PCPN IN OUR NRN COUNTIES MON
BUT FOR NOW KEPT MON INTO MON NGT DRY. OUR NEXT CHANCE OF SHOWERS
AND TSTMS WILL BE ON TUE...AS LOW PRES INTENSIFIES OVER ERN CO AND
WRN KS. LOCATION OF A NWD LIFTING WMFNT WILL BE CRITICAL...BUT IT
DOES APPEAR THERE WILL BE ENOUGH INSTABILITY IN SERN NE FOR SOME
STG TO SVR STORMS TUE AFTN AND EVENING.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 315 AM CDT SUN APR 24 2016
OVERALL THIS PERIOD LOOKS RATHER ACTIVE. DIFFLUENT FLOW SHOULD BE
IN PLACE OVER THE AREA AT THE START OF THIS PERIOD...AHEAD OF A
CLOSED LOW IN SRN WY. WED COULD ALSO BE AN ACTIVE DAY WITH STORMS
BUT WITH FAIRLY WIDESPREAD CLOUDS AND PCPN SVR POTENTIAL IS NOT
CLEAR. IT DOES APPEAR THAT WE WILL DRY OUT THU INTO THU NGT...BUT
RAIN CHANCES SHOULD RETURN FRI AND PROBABLY LAST INTO THE WEEKEND.
&&
.AVIATION...(18Z TAFS FOR KOMA...KLNK...KOFK THROUGH 18Z MONDAY)
ISSUED AT 1235 PM CDT SUN APR 24 2016
GENERALLY VFR CONDITIONS ARE FORECAST OUTSIDE OF SHOWERS AND
THUNDERSTORMS EXPECTED TO OVERSPREAD TAF SITES THIS AFTERNOON INTO
THE EVENING. AREA OF STORMS JUST SOUTHWEST OF KOFK AS OF NOON WILL
MOVE OVER THAT SITE...AND WILL LIKELY MOVE OFF TO THE NORTHEAST BY
20Z. LINE OF STORMS IS EXPECTED TO FIRE EAST OF KOFK AND WEST OF
KLNK BY 21Z OR SO...AND MOVE EAST ACROSS KLNK AND KOMA TAF SITES
BETWEEN 21Z AND 03Z. ATTENDANT IFR VSBYS AND POTENTIAL CIGS WILL
ACCOMPANY THUNDERSTORMS. LARGE HAIL IS ALSO A POSSIBILITY WITH ANY
STORMS BUT WAS NOT MENTIONED IN TAF AT THE MOMENT. STORMS WILL
MOVE EAST OF EASTERN NEBRASKA TAF SITES AFTER 03Z...WITH LINGERING
SHOWERS POSSIBLE OVERNIGHT. OTHERWISE VFR CIGS AND WINDS BECOMING
SOUTHWEST OR WEST BY 12Z CAN BE EXPECTED.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...DERGAN
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1051 AM CDT SUN APR 24 2016
.UPDATE...
ISSUED AT 1051 AM CDT SUN APR 24 2016
995 MB LOW PRES WAS OVER CNTRL SD. THE COLD FRONT ALOFT IS
CURRENTLY OVER CNTRL NEB/KS...SLIGHTLY AHEAD OF THE DRY TROF WHICH
EXTENDS FROM ODX-HDE-NRN. SCT SHWRS HAVE STARTED DEVELOPING IN THE
LAST HR.
DWPTS ARE IN THE MID-UPR 50S AHEAD OF THE SFC TROF. UPDATED THE
FCST USING THE 13 KM RAP WHICH BRINGS VERY DRY DWPTS IN FROM THE W
THIS AFTN. DWPTS ARE IN THE 30S JUST W OF THE FCST AREA AT
IML/OGA/LBF/TIF/BBW.
EXPECT SCT SHWRS TO BECOME TSTMS ESPECIALLY BY 3 PM E OF HWY 281.
SHOULD BE DRY TO THE W OF 281 BY THAT TIME. THE TSTMS SHOULD EXIT
THE FCST AREA AND BE INTO ERN NEB/KS BY 6 PM.
CLOUDS WILL INHIBIT HEATING SOME...BUT STILL EXPECT MLCAPE UP TO
1500 J/KG. DEEP LAYER SHEAR WILL BE ABOUT 40 KTS WITH A FAIRLY
UNIDIRECTIONAL PROFILE. INITIAL STORMS COULD BE SUPERCELLULAR.
MEAN CELL MVMT WILL BE TO THE NE AT 40-45 KTS.
GOES E GOES INTO RAPID SCAN MODE AT 1814Z.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 336 AM CDT SUN APR 24 2016
THE MAIN CONCERN TODAY AND TONIGHT IS HOW WIDESPREAD SHOWERS AND
THUNDERSTORMS WILL BE. LIGHT SCATTERED ACTIVITY IS ONGOING THIS
MORNING AND IS EXPECTED TO BECOME MORE WIDESPREAD AS IT MOVES
EASTWARD. THE MAJORITY ACTIVITY IS EXPECTED TO MOVE EAST OF
HIGHWAY 81 BY SUNRISE. ACTIVITY IS EXPECTED TO DIMINISH BY MID-
MORNING...BUT INCREASE AGAIN DURING THE AFTERNOON. THE HIGH-RES
GUIDANCE INDICATES THE CHANCE FOR SHOWERS AND THUNDERSTORMS TO
DEVELOP AROUND THE TRI-CITIES AND MOVE EASTWARD DURING THE MID
AFTERNOON HOWEVER...HAVE KEPT THE FORECAST IN THIS AREA MAINLY DRY
DUE TO LOW CONFIDENCE ON THIS OCCURRING...SO WILL NEED TO WATCH IF
THIS OCCURS. MAINLY EXPECTING SKIES TO SCATTER ACROSS WESTERN
SECTIONS AND HIGHS TO BE IN THE UPPER 70S AND LOW 80S. COOLER IN
THE EAST WHERE CLOUDS ARE EXPECTED TO PERSIST MUCH OF THE DAY.
THE UPPER LOW WILL MOVE ACROSS THE NE/SD BORDER. THE FRONT/TROUGH
WILL BE SLOW TO MAKE MUCH EASTWARD MOVEMENT UNTIL THE UPPER LOW
BEGINS TO MOVE NORTHEAST. A BIG QUESTION IS HOW QUICKLY WILL THE
UPPER LOW MOVE...WHICH WILL BE IMPORTANT FOR HOW FAR EAST THE
FRONT WILL MOVE. IF IT SLOWS DOWN...AS HIGH-RES GUIDANCE IS
INDICATING...SOME STRONG TO SEVERE STORMS MAY DEVELOP ALONG AND
EAST OF HIGHWAY 281. INSTABILITY OF 1500-2000J/KG MUCAPE AND
45-50KTS SHEAR IS AMPLE FOR ANY STORM TO BE SEVERE. LARGE HAIL AND
DAMAGING WIND ARE THE MAIN THREATS. THESE STORMS WILL QUICKLY MOVE
EAST/NORTHEAST AND SHOULD MOVE INTO EASTERN NEBRASKA AROUND OR
JUST AFTER SUNSET.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 336 AM CDT SUN APR 24 2016
MONDAY THERE IS A WEAK UPPER LEVEL RIDGE AND SURFACE HIGH ACROSS
THE AREA. TEMPERATURES WILL REMAIN ON THE WARM SIDE...BUT A LITTLE
COOLER THAN TODAY. BY MONDAY NIGHT THERE IS A SURFACE LOW
DEVELOPING ON THE HIGH PLAINS AND AN UPPER LEVEL LOW IN THE FOUR
CORNERS REGION. WITH THE SURFACE LOW IN WESTERN KANSAS THE WINDS
ACROSS THE AREA WILL TURN TO THE EAST/SOUTHEAST AND BRING IN
MOISTURE TO THE AREA. THERE COULD BE A LITTLE PRECIPITATION MAINLY
IN THE SOUTHWEST PART OF THE FORECAST AREA LATE MONDAY NIGHT.
ON TUESDAY THE UPPER LEVEL LOW MOVES INTO THE HIGH PLAINS AND
THUNDERSTORMS SPREAD ACROSS THE FORECAST AREA. THE UPPER LEVEL LOW
CONTINUES TO MOVE TO THE NORTHEAST AND ACROSS THE FORECAST AREA
TUESDAY NIGHT. THE SURFACE LOW ALSO MOVES THROUGH THE AREA WITH A
WARM FRONT TO THE EAST OF THE LOW. MUCAPE OF UP TO 5000 J/KG ARE
FORECAST...MAINLY ACROSS NORTH CENTRAL KANSAS. THE WARM FRONT
MOVES TO THE NORTH DURING THE AFTERNOON AND EVENING EVEN WHEN THE
MUCAPE DECREASES SOME. EXPECT THERE TO BE THUNDERSTORMS AND SOME
OF THEM COULD BE STRONG TO SEVERE.
MODELS HAVE A FEW DIFFERENCES FOR WEDNESDAY AND BEYOND. THE TRACK
AND SPEED OF THE UPPER LEVEL LOW ARE A LITTLE DIFFERENT. THE GFS
TAKES THE LOW A LITTLE FURTHER NORTH AND IS A LITTLE FASTER THAN
THE ECMWF. WITH THE FURTHER NORTH TRACK THE PRECIPITATION COMES TO
AN END IN THE SOUTHERN PART OF THE FORECAST AREA A LITTLE EARLIER.
THE THUNDERSTORMS ARE EXPECTED TO CONTINUE ACROSS THE AREA ON
WEDNESDAY. WEDNESDAY NIGHT EVEN THE ECMWF STARTS TO PULL FAR
ENOUGH TO THE NORTH THAT THE PRECIPITATION SHOULD COME TO AN END
FROM SOUTH TO NORTH. THERE IS LITTLE CAPE LEFT WEDNESDAY NIGHT SO
HAVE JUST SHOWERS. ON THURSDAY THERE STILL COULD BE A FEW SHOWERS
IN THE FAR NORTHERN PART OF THE REGION.
THE PERIOD THURSDAY NIGHT THROUGH SATURDAY THERE IS ANOTHER UPPER
LEVEL SYSTEM SET TO AFFECT THE AREA. THE MODELS CONTINUE TO HAVE A
FEW DIFFERENCES IN TRACK AND STRENGTH OF THE LOW. EVEN WITH THE
DIFFERENCES BOTH THE GFS AND ECMWF HAVE SOME PRECIPITATION ACROSS
THE AREA AND THIS WILL BE ANOTHER CHANCE FOR THUNDERSTORMS AGAIN.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z MON MORNING)
ISSUED AT 550 AM CDT SUN APR 24 2016
THE MAIN AVIATION FORECAST CONCERN IS THE CHANCE FOR SCATTERED
SHOWERS/THUNDERSTORMS TO IMPACT THE TERMINALS THIS AFTERNOON IN
ADDITION TO A WIND SHIFT.
A WIND SHIFT ALONG A SURFACE FRONT/TROUGH WILL MOVE THROUGH THE
AREA CAUSING WINDS TO BECOME MORE SOUTHWESTERLY. BRIEF SHOWERS AND
ISOLATED THUNDERSTORMS MAY IMPACT THE TERMINALS THIS AFTERNOON
AROUND 18Z. DUE TO THE ISOLATED NATURE HAVE LEFT THIS OUT...BUT IT
COULD IMPACT BOTH KEAR/KGRI. THEN AROUND 20Z HIGH-RES GUIDANCE
SHOWS THE CHANCE FOR THUNDERSTORMS TO DEVELOP ALONG THE FRONT.
THIS ACTIVITY COULD ORIGINATE AROUND THE KGRI TERMINAL. IT WILL
QUICKLY MOVE EASTWARD AND SKIES WILL CLEAR. AT THIS TIME DUE TO
THE UNCERTAINTY THAT STORMS MAY ACTUALLY DEVELOP AS FAR WEST AS
KGRI...HAVE LEFT ANY THUNDERSTORM MENTION OUT OF THE FORECAST.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...BILLINGS WRIGHT
LONG TERM...JCB
AVIATION...BILLINGS WRIGHT
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
624 AM CDT SUN APR 24 2016
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 315 AM CDT SUN APR 24 2016
THE POTENTIAL FOR SEVERE STORMS TODAY IS THE MAIN FCST CONCERN.
CLOSED LOW AT 500 MB WAS NEAR THE UT/WY/CO BORDER AREA AT 00Z WITH
12 HOUR HEIGHT FALLS OF UP TO AROUND 80 METERS JUST AHEAD OF THE
CIRCULATION CENTER. THERE WAS A JET SEGMENT OF AROUND 70 KTS AT
300 MB NEAR THE UT/CO BORDER. AT 700 MB...THERMAL RIDGE AXIS
STRETCHED FROM SWRN NM UP INTO SERN MT. MOIST AXIS AT 850 MB
EXTENDED FROM TX INTO THE DKTS. WATER VAPOR STLT IMAGERY EARLY
THIS MORNING SHOWED THE MID TROPOSPHERIC LOW HAD PROGRESSED INTO
CENTRAL WY. SFC ANLYS AT 08Z HAD A LOW PRES CENTER OVER WRN SD.
A WMFNT EXTENDED E/NE FROM THE LOW INTO MN AND A CDFNT EXTENDED
S/SW INTO NERN NM. DEWPOINTS AHEAD OF THE CDFNT WERE IN THE UPPER
40S AND LOWER 50S.
TODAY...CURRENT SHOWERS AND TSTMS TO OUR WEST SHOULD MOVE INTO
THE AREA THIS MORNING BUT IT APPEARS THESE WILL STAY BELOW SVR
LIMITS. RECENT RUNS OF THE RAP AND HRRR MODELS DEPICT VIGOROUS
STORM DEVELOPMENT IN OUR AREA THIS AFTN. SFC-500 METER MIXED
LAYER CAPE VALUES COULD REACH AROUND 2000 J/KG BY MID AFTN IN OUR
WRN ZONES...BASED ON DEWPOINTS RISING TO THE MID/UPPER 50S. THE
STRONGEST STORMS SHOULD FORM THERE AND THEN DVLP EWD. ZERO TO 6 KM
SHEAR VALUES OF 35-45 KTS SHOULD BE ENOUGH FOR SOME SUPERCELLS...
WITH HAIL THE MOST LIKELY HAZARD. EXPERIMENTAL HRRR AND MANY OTHER
CONVECTION ALLOWING MODELS SHOW SIMILAR RESULTS. LOOK FOR HIGHS 75
TO 80.
STORMS SHOULD CONTINUE TO DVLP EWD AND MAINLY BE OUT OF THE AREA
BY 06Z TNGT. SOME SMALL CHANCE OF SHOWERS MAY LINGER INTO THE
EARLY MORNING HOURS...MAINLY NEAR THE SD BORDER. SFC LOW SHOULD BE
JUST NW OF KSUX BY 12Z MON...THEN THAT WILL MOVE TO NEAR THE
WI/IA/MN BORDER AREA BY 00Z TUE. NW SFC WINDS SHOULD PULL COOLER
AIR INTO NERN NE FOR MON...BUT COOLING WILL BE LESS FOR SERN NE
AND SWRN IA. THERE COULD BE SOME LGT PCPN IN OUR NRN COUNTIES MON
BUT FOR NOW KEPT MON INTO MON NGT DRY. OUR NEXT CHANCE OF SHOWERS
AND TSTMS WILL BE ON TUE...AS LOW PRES INTENSIFIES OVER ERN CO AND
WRN KS. LOCATION OF A NWD LIFTING WMFNT WILL BE CRITICAL...BUT IT
DOES APPEAR THERE WILL BE ENOUGH INSTABILITY IN SERN NE FOR SOME
STG TO SVR STORMS TUE AFTN AND EVENING.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 315 AM CDT SUN APR 24 2016
OVERALL THIS PERIOD LOOKS RATHER ACTIVE. DIFLUENT FLOW SHOULD BE
IN PLACE OVER THE AREA AT THE START OF THIS PERIOD...AHEAD OF A
CLOSED LOW IN SRN WY. WED COULD ALSO BE AN ACTIVE DAY WITH STORMS
BUT WITH FAIRLY WIDESPREAD CLOUDS AND PCPN SVR POTENTIAL IS NOT
CLEAR. IT DOES APPEAR THAT WE WILL DRY OUT THU INTO THU NGT...BUT
RAIN CHANCES SHOULD RETURN FRI AND PROBABLY LAST INTO THE WEEKEND.
&&
.AVIATION...(12Z TAFS FOR KOMA...KLNK...KOFK THROUGH 12Z MONDAY)
ISSUED AT 612 AM CDT SUN APR 24 2016
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO MOVE THROUGH
KOMA AND KLNK THIS MORNING. VFR CONDITIONS ARE EXPECTED AFTER
14-15Z UNTIL THUNDERSTORMS BEGIN TO BLOSSOM AND MOVE EAST ACROSS
THE REGION MID AFTERNOON...SOME OF WHICH COULD BE SEVERE.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...KERN
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
315 AM CDT SUN APR 24 2016
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 315 AM CDT SUN APR 24 2016
THE POTENTIAL FOR SEVERE STORMS TODAY IS THE MAIN FCST CONCERN.
CLOSED LOW AT 500 MB WAS NEAR THE UT/WY/CO BORDER AREA AT 00Z WITH
12 HOUR HEIGHT FALLS OF UP TO AROUND 80 METERS JUST AHEAD OF THE
CIRCULATION CENTER. THERE WAS A JET SEGMENT OF AROUND 70 KTS AT
300 MB NEAR THE UT/CO BORDER. AT 700 MB...THERMAL RIDGE AXIS
STRETCHED FROM SWRN NM UP INTO SERN MT. MOIST AXIS AT 850 MB
EXTENDED FROM TX INTO THE DKTS. WATER VAPOR STLT IMAGERY EARLY
THIS MORNING SHOWED THE MID TROPOSPHERIC LOW HAD PROGRESSED INTO
CENTRAL WY. SFC ANLYS AT 08Z HAD A LOW PRES CENTER OVER WRN SD.
A WMFNT EXTENDED E/NE FROM THE LOW INTO MN AND A CDFNT EXTENDED
S/SW INTO NERN NM. DEWPOINTS AHEAD OF THE CDFNT WERE IN THE UPPER
40S AND LOWER 50S.
TODAY...CURRENT SHOWERS AND TSTMS TO OUR WEST SHOULD MOVE INTO
THE AREA THIS MORNING BUT IT APPEARS THESE WILL STAY BELOW SVR
LIMITS. RECENT RUNS OF THE RAP AND HRRR MODELS DEPICT VIGOROUS
STORM DEVELOPMENT IN OUR AREA THIS AFTN. SFC-500 METER MIXED
LAYER CAPE VALUES COULD REACH AROUND 2000 J/KG BY MID AFTN IN OUR
WRN ZONES...BASED ON DEWPOINTS RISING TO THE MID/UPPER 50S. THE
STRONGEST STORMS SHOULD FORM THERE AND THEN DVLP EWD. ZERO TO 6 KM
SHEAR VALUES OF 35-45 KTS SHOULD BE ENOUGH FOR SOME SUPERCELLS...
WITH HAIL THE MOST LIKELY HAZARD. EXPERIMENTAL HRRR AND MANY OTHER
CONVECTION ALLOWING MODELS SHOW SIMILAR RESULTS. LOOK FOR HIGHS 75
TO 80.
STORMS SHOULD CONTINUE TO DVLP EWD AND MAINLY BE OUT OF THE AREA
BY 06Z TNGT. SOME SMALL CHANCE OF SHOWERS MAY LINGER INTO THE
EARLY MORNING HOURS...MAINLY NEAR THE SD BORDER. SFC LOW SHOULD BE
JUST NW OF KSUX BY 12Z MON...THEN THAT WILL MOVE TO NEAR THE
WI/IA/MN BORDER AREA BY 00Z TUE. NW SFC WINDS SHOULD PULL COOLER
AIR INTO NERN NE FOR MON...BUT COOLING WILL BE LESS FOR SERN NE
AND SWRN IA. THERE COULD BE SOME LGT PCPN IN OUR NRN COUNTIES MON
BUT FOR NOW KEPT MON INTO MON NGT DRY. OUR NEXT CHANCE OF SHOWERS
AND TSTMS WILL BE ON TUE...AS LOW PRES INTENSIFIES OVER ERN CO AND
WRN KS. LOCATION OF A NWD LIFTING WMFNT WILL BE CRITICAL...BUT IT
DOES APPEAR THERE WILL BE ENOUGH INSTABILITY IN SERN NE FOR SOME
STG TO SVR STORMS TUE AFTN AND EVENING.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 315 AM CDT SUN APR 24 2016
OVERALL THIS PERIOD LOOKS RATHER ACTIVE. DIFLUENT FLOW SHOULD BE
IN PLACE OVER THE AREA AT THE START OF THIS PERIOD...AHEAD OF A
CLOSED LOW IN SRN WY. WED COULD ALSO BE AN ACTIVE DAY WITH STORMS
BUT WITH FAIRLY WIDESPREAD CLOUDS AND PCPN SVR POTENTIAL IS NOT
CLEAR. IT DOES APPEAR THAT WE WILL DRY OUT THU INTO THU NGT...BUT
RAIN CHANCES SHOULD RETURN FRI AND PROBABLY LAST INTO THE WEEKEND.
&&
.AVIATION...(06Z TAFS FOR KOMA...KLNK...KOFK THROUGH 06Z MONDAY)
ISSUED AT 1133 PM CDT SAT APR 23 2016
PRIMARY AVIATION CONCERN REVOLVES AROUND 2 ROUNDS OF THUNDERSTORMS
THAT WILL AFFECT TAF SITES. THE FIRST WILL BE EARLY THIS MORNING
09-14Z. SECOND ROUND OF STORMS EXPECTED 21-02Z...WHICH WOULD BE
STRONGER WITH A SLIGHT RISK OF HAIL AND DAMAGING WINDS. SECONDARY
CONCERN IS NON CONVECTIVE LOW LEVEL WIND SHEAR...WITH WINDS AT
FLIGHT LEVEL 020 AROUND 45-50 KNOTS FROM NOW THROUGH ABOUT 11-14Z.
OTHERWISE VFR CONDITIONS PREVAIL WITH SOUTHEASTERLY WINDS AT 15
TO 30 KNOTS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
321 PM PDT SUN APR 24 2016
.SYNOPSIS...UNSETTLED WEATHER WILL SETTLE IN OVER THE AREA FOR THE
NEXT SEVERAL DAYS AS A SERIES OF SPRING STORM SYSTEMS MOVE THROUGH
THE REGION. THE FIRST SYSTEM TONIGHT WILL BRING INCREASING WINDS AND
CHANCES FOR PRECIPITATION TO PARTS OF THE AREA THAT WILL CONTINUE
THROUGH MONDAY EVENING. A BRIEF BREAK IS EXPECTED TUESDAY BEFORE
ANOTHER STORM SYSTEM MOVES IN MIDWEEK WITH RENEWED SHOWER CHANCES
AND MORE GUSTY WINDS.
&&
.DISCUSSION...ENERGY FROM THE NEXT PACIFIC SYSTEM IS BEGINNING TO
MOVE INTO THE AREA WITH GUSTY SOUTHERLY WINDS DEVELOPING ACROSS MUCH
OF THE REGION THIS AFTERNOON. MID AND HIGH CLOUDS HAVE EXPANDED TO
ACROSS MOST OF THE AREA AS WELL. A FEW LIGHTNING STRIKES WERE NOTED
IN THE SIERRA BUT JUST NORTH OF OUR AREA OF RESPONSIBILITY FOR THE
MOMENT. THE SYSTEM WILL MOVE INTO THE AREA TONIGHT AND MONDAY WITH A
BROAD CLOSED LOW DEVELOPING OVER THE SOUTHERN GREAT BASIN EARLY
MONDAY AND THEN MOVE EAST OF THE AREA MONDAY NIGHT INTO TUESDAY.
STRONG WINDS WILL DEVELOP OVER THE WESTERN PORTIONS OF SAN
BERNARDINO COUNTY LATER THIS AFTERNOON AND CONTINUE THROUGH MUCH OF
MONDAY WHERE A WIND ADVISORY IS IN EFFECT. A COLD FRONT WILL MOVE
INTO THE NORTHWEST CWA MONDAY MORNING AND GUSTY NORTHWEST WINDS ARE
EXPECTED TO DEVELOP BEHIND THE FRONT OVER ESMERALDA AND CENTRAL NYE
COUNTIES. A WIND ADVISORY HAS BEEN ISSUED FOR THESE AREAS FOR
MONDAY. STRONG WINDS ACROSS THE MOJAVE DESERT WILL SPREAD EASTWARD
ACROSS SOUTHERN SAN BERNARDINO INTO SOUTHERN MOHAVE COUNTIES MONDAY
AFTERNOON AND CONTINUE INTO THE EVENING. A WIND ADVISORY HAS BEEN
ISSUED FOR THESE AREAS FOR MONDAY AFTERNOON. WINDS WILL DECREASE
AREA WIDE BY MIDNIGHT MONDAY WITH LIGHTER WINDS EXPECTED TUESDAY
BEHIND THE SYSTEM.
OTHER THAN WIND, SHOWERS AND ISOLATED THUNDERSTORMS WILL
DEVELOP OVER THE SIERRA AND EASTWARD ACROSS THE SOUTHERN GREAT BASIN
THIS EVENING WITH SHOWERS CONTINUING THROUGH THE NIGHT. MOST AREAS
NORTH OF I-40 WILL HAVE A CHANCE OF RAIN AND MOUNTAIN SNOW MONDAY
WITH SHOWER CHANCES DECREASING MONDAY NIGHT. SNOW IS EXPECTED IN THE
HIGHER ELEVATION ABOVE 6500 FEET WITH 1-3 INCHES POSSIBLE IN LINCOLN
COUNTY THROUGH MID DAY MONDAY. DECIDED AGAINST A WINTER WEATHER
ADVISORY FOR NOW BASED ON EXPECTED ACCUMULATIONS AND RECENT WARM
CONDITIONS.
SHORTWAVE RIDGING ON TUESDAY QUICKLY GIVES WAY TO THE NEXT SYSTEM
MOVING INTO THE AREA EARLY WEDNESDAY. THIS ONE DEVELOPS FURTHER ONCE
IT MOVES OVER THE SOUTHWEST AND ADDITIONAL SHOWER CHANCES ARE
EXPECTED. STRONG WINDS ARE AGAIN FORECAST TO DEVELOP OVER THE
WESTERN MOJAVE DESERT WEDNESDAY AND HEADLINES MAY BE NECESSARY.
DEPENDING ON THE EVENTUAL TRACK OF THE SYSTEM, MOST AREAS COULD SEE
AT LEAST A SLIGHT CHANCE OF SHOWERS WEDNESDAY/THURSDAY. MODELS ARE
IN PRETTY GOOD AGREEMENT THAT IMPACTS FROM THIS SYSTEM WILL BE OVER
BY EARLY FRIDAY.
A BREAK FROM ACTIVE WEATHER IS POSSIBLE FRIDAY/SATURDAY BUT ENSEMBLE
SPREAD IS HIGH AND MODEL SOLUTIONS ARE ALL OVER THE PLACE FOR NEXT
WEEKEND. FOR WHAT THEY ARE WORTH, THE 12Z MODELS AGREE ON A MOSTLY
DRY...WINDY INSIDE SLIDER. BUT WE`LL SEE.
&&
.AVIATION...FOR MCCARRAN...CLOUDS WILL CONTINUE TO LOWER OVERNIGHT
WITH SCT-BROKEN SKIES AROUND 10KFT EXPECTED WITH PERIODS OF
OVERCAST. STRONGER SOUTHWEST WINDS ARRIVE LATE THIS AFTERNOON/EARLY
EVENING IN THE 10-15 KNOT RANGE. WINDS WILL CONTINUE TO FAVOR WEST
AND SOUTHWEST DIRECTIONS THROUGH MONDAY WITH SPEEDS OF 15-25 KNOTS
AND GUSTS AROUND 30 KNOTS. CANNOT RULE OUT SOME LIGHT SHOWERS AROUND
THE VALLEY TONIGHT AND MONDAY, BUT CONFIDENCE IS LOW THAT THEY WILL
MOVE OVER THE AIRFIELD. MOUNTAIN OBSCURATIONS AND MECHANICAL
TURBULENCE ARE POSSIBLE THROUGH MONDAY.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...CLOUD BASES WILL LOWER BECOMING SCT-BKN AROUND 10KFT,
ESPECIALLY NORTH OF INTERSTATE 40. STRONG AND GUSTY SOUTHWEST WINDS
WILL IMPACT TAF SITES NEAR KDAG AND KNXP THROUGH THE PERIOD WITH
GUSTS OVER 35KTS LIKELY AND AREAS OF BLOWING DUST. SHOWERS, MOUNTAIN
OBSCURATIONS AND MECHANICAL TURBULENCE ARE POSSIBLE THROUGH MONDAY
AROUND KBIH, KVGT, AND KHND. &&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION IS NOT
ANTICIPATED THIS WEEKEND. HOWEVER, SPOTTERS SHOULD REPORT ANY
SIGNIFICANT WEATHER ACCORDING TO STANDARD OPERATING PROCEDURES.
&&
$$
DISCUSSION...SALMEN
AVIATION...PADDOCK
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
Area Forecast Discussion
National Weather Service Reno NV
231 PM PDT SUN APR 24 2016
.SYNOPSIS...
Low pressure will move through western Nevada tonight and Monday.
Light snow is expected near the Oregon Border tonight while most
locations see a few showers and brisk northwest winds. After a
break Tuesday, unsettled weather returns for Wednesday and
Thursday. A warming trend with dry weather is looking more likely
for next weekend.
&&
.SHORT TERM...
Scattered showers have developed across Northeast California and
Western NV this afternoon and will continue into the evening. With
the cloud cover, instability has not been as great as anticipated,
but a few thunderstorms remain possible through sunset. Localized
rainfall amounts up to 1/3" are possible in the heaviest showers.
Snow levels are running around 6000 feet into this evening, but
will drop as the cold upper low moves in.
Overnight and into Monday, have made a few adjustments based on
latest trends and model forecasts. The main adjustments were to
increase the precip chances north of a Susanville-Lovelock line
and increase winds a bit more Monday afternoon. With the upper low
diving into Western NV tonight, the GFS, HRRR and EC all show an
area of deformation setting up from Austin, NV to Cedarville, CA.
QPF amounts are averaging 1/4" to 1/2" in this band. Snow levels
are expected to drop to near 4000-4500 feet. Issued a winter
weather advisory for light snow amounts near the Oregon Border
where it is more likely to stick to roads as they will be in the
cold air longer.
Monday morning that band dissipates as the upper low moves into
southern NV. The low is moving through a little faster and will
take the upper cold pool with it resulting in more stabilization.
Still expect some showers in the afternoon, but they are looking
more likely to be confined to areas south of highway 50. It still
looks quite cool, and a brisk NW wind of 15-25 mph with higher
gusts will make it feel colder. With these winds aligned with
Pyramid Lake, issued a Lake Wind Advisory there.
Monday night and Tuesday will see quiet weather under a short wave
ridge. Then the next upper low is expected to arrive Tuesday night
into Wednesday. This one will not be quite as cold, although it
will have some moisture. Forcing also does not look overly strong,
so at this point we are expecting showers again with a few
thunderstorms possible. Wallmann
.LONG TERM...Thursday through Sunday...
Active weather continues late next week as mean upper level
troughing remains fixed over the Western United States. Low
pressure that will move into the region Wednesday will slowly exit
into the Inter-Mountain West Friday night into Saturday. Snow
levels remain around 6000-7000 feet through Friday before rising
7000-8000 feet over the weekend. Kept mention of thunderstorms for
Thursday afternoon since sufficient instability remains.
Models have changed a little from previous runs for Saturday and
Sunday. Previously, deterministic runs were showing another low
dropping into the backside of the trough impacting Western Nevada
and the Sierra. Now, deterministic runs and ensembles are favoring
a more eastward track with low pressure pushing through Eastern
Nevada and Utah. As a result, have begun to back off of
precipitation chances over the weekend. Correspondingly, have
increased daily highs for the weekend as well with temperatures
approaching 70 degrees for Western Nevada Valleys. Boyd
&&
.AVIATION...
Low pressure will continue to impact the region this afternoon
into Monday at all terminals. Expect periods of IFR/MVFR in the
Sierra by Monday morning with periods of snow. MVFR conditions
will be possible for Sierra Front with snow levels dragging down
to around 4500 feet. It is possible that there could be periods of
IFR and light rain/snow mix at KRNO and KCXP Monday morning as
well. However, surface temperatures for Sierra Front terminals
will be too warm to allow for much/any snow to stick on the
tarmac.
Winds will increase with gusts generally up to 30 knots for
Sierra Front terminals while winds at KTVL/KTRK being lighter due
to precipitation influences. KMMH may see a few intermittent gusts
up to 40 knots Monday. Boyd/Hoon
&&
.REV Watches/Warnings/Advisories...
NV...Lake Wind Advisory from 6 AM to 8 PM PDT Monday for Pyramid Lake
in NVZ004.
Winter Weather Advisory from 8 PM this evening to 8 AM PDT
Monday NVZ005.
CA...Winter Weather Advisory from 8 PM this evening to 8 AM PDT
Monday CAZ070.
&&
$$
For more information from the National Weather Service visit...
http://weather.gov/reno
AREA FORECAST DISCUSSION
NWS BISMARCK ND
925 PM CDT MON APR 25 2016
.UPDATE...
ISSUED AT 923 PM CDT MON APR 25 2016
LIGHT SNOW NOW ACROSS MUCH OF WEST CENTRAL NORTH DAKOTA AS
TEMPERATURES HAVE FALLEN INTO THE LOWER 30S. ALSO HAVE 1 TO 2
INCHES OF SNOW FOR THIS AREA TONIGHT.
UPDATE ISSUED AT 611 PM CDT MON APR 25 2016
TEMPERATURES REMAIN NEAR THE RAIN/SNOW THRESHOLD ACROSS SOUTHWEST
AND WEST CENTRAL NORTH DAKOTA THIS EVENING. WHILE THERE MAY BE A
SPOT OR TWO OF SLEET MIXED IN FOR THE MOST PART A MIX OF RAIN AND
SNOW LOOKS TO PREDOMINATE. TWEAKED THE TEMPERATURES A BIT COOLER
THROUGH THE EVENING HOURS WHICH WILL MAINTAIN MORE SNOW AS A
WEATHER ELEMENT WEST. OTHERWISE SINCE TEMPERATURES BOTTOM OUT IN
THE LOWER 30S DONT EXPECT ACCUMULATIONS MORE THAN AN INCH ON
GRASSY AREAS WEST CENTRAL TONIGHT.
&&
.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 ANALYSES. 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 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 611 PM CDT MON APR 25 2016
BROAD AREA OF COOL MOIST AIR REMAINS IN PLACE ACROSS NORTH DAKOTA WITH
IFR CEILINGS FROM KDIK- KBIS- KJMS TONIGHT AND TUESDAY. MVFR EXPECTED
KISN-KMOT BECOMING IFR AFTER 12Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...CJS
LONG TERM...CJS
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
628 PM CDT MON APR 25 2016
.UPDATE...
ISSUED AT 611 PM CDT MON APR 25 2016
TEMPERATURES REMAIN NEAR THE RAIN/SNOW THRESHOLD ACROSS SOUTHWEST
AND WEST CENTRAL NORTH DAKOTA THIS EVENING. WHILE THERE MAY BE A
SPOT OR TWO OF SLEET MIXED IN FOR THE MOST PART A MIX OF RAIN AND
SNOW LOOKS TO PREDOMINATE. TWEAKED THE TEMPERATURES A BIT COOLER
THROUGH THE EVENING HOURS WHICH WILL MAINTAIN MORE SNOW AS A
WEATHER ELEMENT WEST. OTHERWISE SINCE TEMPERATURES BOTTOM OUT IN
THE LOWER 30S DONT EXPECT ACCUMULATIONS MORE THAN AN INCH ON
GRASSY AREAS WEST CENTRAL TONIGHT.
&&
.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 ANALYSES. 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 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 611 PM CDT MON APR 25 2016
BROAD AREA OF COOL MOIST AIR REMAINS IN PLACE ACROSS NORTH DAKOTA WITH
IFR CEILINGS FROM KDIK- KBIS- KJMS TONIGHT AND TUESDAY. MVFR EXPECTED
KISN-KMOT BECOMING IFR AFTER 12Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...CJS
LONG TERM...CJS
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1218 PM CDT SUN APR 24 2016
.UPDATE...
ISSUED AT 1218 PM CDT SUN APR 24 2016
CURRENT FORECAST IS ON TRACK WITH SEVERAL BANDS OF SHOWERS AND
THUNDERSTORMS ROTATING AROUND A VERTICALLY STACKED CLOSED LOW
CIRCULATING IN SOUTHWEST SOUTH DAKOTA. THE PREVIOUS FORECAST AND
LATEST HRRR BOTH HAVE HAD THE RIGHT IDEA WITH THE CURRENT POP
TRENDS. THUS VERY LITTLE IF ANY ADJUSTMENTS NEEDED AT THIS TIME.
WINDS STILL STRONGEST IN NORTHERN NORTH DAKOTA WITH RUGBY
SUSTAINED AT 30 MPH. HOWEVER AREAL COVERAGE IS LIMITED AND TRENDS
WITH THESE SUSTAINED WINDS WILL FALL DURING THE AFTERNOON. THUS
WILL CONTINUE TO MESSAGE THE GUSTY WINDS VIA THE HAZARDOUS
WEATHER OUTLOOK THIS AFTERNOON.
INTERESTING THE 12Z NAM/GFS/SREF ALL DEVELOP A CLOSED MID LEVEL
CIRCULATION/700MB LOW...LATE SUNDAY NIGHT THROUGH MONDAY. THIS LOW
MOVES FROM EAST TO WEST WITHIN THE DEFORMATION ZONE THAT REMAINS
STATIONARY ACROSS CENTRAL AND SOUTHERN NORTH DAKOTA. THE NET
RESULT WILL LIKELY BE A WET MONDAY DEVELOPING FROM EAST TO WEST.
MORE ON THIS IN THE AFTERNOON DISCUSSION.
UPDATE ISSUED AT 1056 AM CDT SUN APR 24 2016
QUICK UPDATE FOR CONVECTION DEVELOPING NORTH OF HIGHWAY 2. HAVE
ADDED IN SCATTERED THUNDERSTORMS IN THIS AREA TAPERING TO ISOLATED
NEAR THE CANADIAN BORDER UNTIL EARLY AFTERNOON. UPDATES
FORTHCOMING.
UPDATE ISSUED AT 954 AM CDT SUN APR 24 2016
LATEST WATER VAPOR IMAGERY LOOP SHOWS THE DRY SLOT FROM PREVIOUS
DISCUSSION HAS WRAPPED TOTALLY AROUND THE VERTICALLY STACKED
MID/UPPER LOW. OCCLUDED SYSTEM NOW CIRCULATING IN SOUTHWEST SOUTH
DAKOTA WILL CONTINUE TO SHIFT EAST TODAY...RIDING ALONG THE SOUTH
DAKOTA/NEBRASKA BORDER. DEFORMATION ZONE EVIDENT ACROSS SOUTHERN
NORTH DAKOTA. RADAR SHOWS ECHOES FILLING IN ACROSS THIS AREA...AND
CURRENT POPS ON TRACK FROM PREVIOUS UPDATE. DID ADJUST WINDS A BIT
HIGHER TODAY USING A BLEND OF THE MAV/MET GUIDANCE GIVEN CURRENT
OBSERVATIONS. AFTER COORDINATING WITH GRAND FORKS...WILL HOLD OFF
ON ANY WIND ADVISORY...AS MINIMAL AREAL COVERAGE AND OVERALL
LENGTH OF TIME MEETING SUSTAINED 30 MPH IS MARGINAL. ALSO COORDINATED
WITH GRAND FORKS TO INCREASE POPS TONIGHT AS STRATIFORM PRECIP
SHIELD ON THE NORTHWEST SIDE OF THE STACKED LOW IS FORECAST TO
ENVELOP MOST OF CENTRAL/SOUTHERN NORTH DAKOTA.
UPDATE ISSUED AT 649 AM CDT SUN APR 24 2016
THE 06-10 UTC HIGH RESOLUTION SUITES HAVE CONSISTENTLY SHIFTED
THE AXIS OF HEAVIEST RAINFALL FURTHER NORTHERN INTO THE HIGHWAY
200 AND US HIGHWAY 2 CORRIDORS. THIS IS CONSISTENT WITH A DRY SLOT
EVIDENT ON SATELLITE THROUGH 1130 UTC ACROSS WESTERN SOUTH DAKOTA
AND NEBRASKA THAT WILL PROPAGATE NORTH INTO SOUTHWEST AND SOUTH
CENTRAL NORTH DAKOTA THROUGH THE DAY. THUS SHIFTED THE GREATEST
POPS AND RAINFALL TOTALS FURTHER NORTH IN LINE WITH THE
AFOREMENTIONED GUIDANCE SUITES. MAINTAINED THE MENTION OF THUNDER
SOUTH OF US HIGHWAY 2 WITH MODEST ELEVATED INSTABILITY WITH STRONG
DEEP LAYER SHEAR.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 318 AM CDT SUN APR 24 2016
WIDESPREAD RAINFALL IS EXPECTED TODAY AND TONIGHT AS THE NORTHERN
PLAINS LOW DEEPENS AND LOW-LEVEL FRONTOGENESIS INTENSIFIES.
ISOLATED THUNDERSTORMS ARE POSSIBLE THIS MORNING WITH AN UNSTABLE
ELEVATED MOIST LAYER.
HIGH-RES MODELS CONTINUE TO DELAY THE ONSET OF PRECIPITATION.
CURRENT RADAR ANALYSIS INDICATED ZERO PRECIPITATION ACROSS WESTERN
AND CENTRAL NORTH DAKOTA AS OF 4 AM. THIS IS EXPECTED TO CHANGE
LATER THIS MORNING AS UPPER LEVEL SUPPORT AND INCREASED MOISTURE
ADVECTION MOVE INTO THE AREA. THE AXIS OF HEAVIEST RAINFALL STILL
APPEARS TO LINE UP BETWEEN I94 AND HIGHWAY 200...WHERE 1 TO 1.5
INCHES OF RAIN IS EXPECTED.
ACROSS FAR NORTHERN NORTH DAKOTA THERE MAY BE A BRIEF TRANSITION
FROM RAIN TO FREEZING RAIN OR SNOW AS TEMPERATURES FALL BELOW
CRITICAL THRESHOLDS.
GUSTY NORTHEAST WINDS WILL CONTINUE TODAY. THE STRONGEST WINDS
ARE FORECAST ALONG AND NORTH OF HIGHWAY 2...WITH THE TURTLE
MOUNTAINS PINPOINTED FOR THE HIGHEST SUSTAINED WINDS OF AROUND 30
MPH AND GUSTS TO 45 MPH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 318 AM CDT SUN APR 24 2016
SEVERAL WAVES WILL EJECT ACROSS THE PLAINS THIS WEEK. THIS WILL
LEAD TO RAIN CHANCES THROUGH THURSDAY. MODELS ARE FAIRLY
CONSISTENT IN TIMING AND PLACEMENT OF PRECIPITATION. AT THIS TIME
IT APPEARS WESTERN AND SOUTHERN NORTH DAKOTA HAVE THE HIGHEST
CHANCES OF SEEING RAIN MONDAY THROUGH THURSDAY.
WITH PERSISTENT EAST/NORTHEAST WINDS AND STUBBORN CLOUD
COVER...TEMPERATURES WILL REMAIN COOL WITH READINGS DURING THE DAY
IN THE 40S AND LOW 50S AND OVERNIGHT LOWS IN THE 30S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1218 PM CDT SUN APR 24 2016
IFR/LIFR CONDITIONS WILL CONTINUE THROUGH AT LEAST MIDDAY MONDAY
ACROSS SOUTHWEST AND SOUTH CENTRAL ND. IN NORTHERN AREAS...FROM
KISN TO KMOT...MVFR CONDITIONS MAY PREVAIL. RAIN IS FORECAST FOR
MOST OF WESTERN AND CENTRAL ND THROUGH MONDAY...BUT THE CHANCE OF
THUNDERSTORMS WILL DIMINISH BY 00 UTC THIS EVENING. SOME SNOW IS
POSSIBLE LATE TONIGHT AND MONDAY MORNING IN THE WEST AND NORTH.
FINALLY...EAST-NORTHEAST WINDS WHICH ARE GUSTING UP TO 35 KT AT
MIDDAY WILL GRADUALLY DECREASE BY TONIGHT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...CJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1236 AM CDT SUN APR 24 2016
.UPDATE...
ISSUED AT 1225 AM CDT SUN APR 24 2016
TWEAKED PRECIPITATION CHANCES WITH THIS UPDATE. RAIN SHOWERS ARE
SLOW TO DEVELOP LATE TONIGHT. LATEST HIGH-RES DATA INDICATES A
SLIGHTLY DELAYED DEVELOPMENT OF PRECIPITATION COMPARED TO THE
PREVIOUS FORECASTS. THEREFORE DELAYED THE MENTION OF LIKELY
CHANCES TILL THIS MORNING. LOW LEVEL FRONTOGENESIS CONTINUES TO
STRENGTHEN TONIGHT...HOWEVER...THE MAIN UPPER LEVEL WAVE WAS STILL
LOCATED ACROSS SOUTH DAKOTA. THUNDERSTORMS STILL APPEAR POSSIBLE
ACROSS SOUTHERN NORTH DAKOTA. ISOLATED THUNDERSTORMS HAVE
DEVELOPED WEST OF THE BLACK HILLS IN ASSOCIATION WITH THE 700 MB
LOW.
UPDATE ISSUED AT 921 PM CDT SAT APR 23 2016
WIDELY SCATTERED SHOWERS NORTHEAST DECREASING. SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS APPROACHING THE SOUTHWEST. EXPECT
AROUND OR SHORTLY AFTER MIDNIGHT. CONTINUED BREEZY TO WINDY.
UPDATE ISSUED AT 636 PM CDT SAT APR 23 2016
DEEP LOW PRESSURE OVER WESTERN SOUTH DAKOTA AND HIGH PRESSURE
ACROSS MANITOBA WERE ENHANCING THE LOW LEVEL WINDS ACROSS NORTH
DAKOTA. MOST AREAS HAD EAST WINDS OF 20 TO 35 MPH WITH A FEW
SITES ABOVE 40 MPH. EXPECT THE WINDS TO CONTINUE TONIGHT. WATER
VAPOR CHANNEL SHOWS THE 700 MB UPPER LOW IN THE VICINITY OF WEST
CENTRAL WYOMING. SCATTERED THUNDERSTORMS HAVE DEVELOPED INTO SOUTH
CENTRAL MONTANA SOUTHEAST THROUGH EASTERN WYOMING. EXPECT THIS
AREA TO ROTATE NORTHEAST INTO SOUTHWEST NORTH DAKOTA LATE TONIGHT.
OTHERWISE FOR THE NEXT 6 HOURS OR SO LOOKING AT SOME INCREASING
CLOUDS AND A STEADY EAST WIND OF 20 TO 40 MPH.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 313 PM CDT SAT APR 23 2016
MAIN HIGHLIGHTS THROUGH SUNDAY AFTERNOON: RAINFALL AMOUNTS
ESPECIALLY LOCATIONS WHERE TOTALS EXCEED ONE INCH...A FEW STRONG
THUNDERSTORMS SOUTHWEST TONIGHT WITH POSSIBLE SMALL HAIL AND
GUSTY WINDS...AND POTENTIAL WIND ADVISORY TURTLE MOUNTAINS AND
VICINITY SUNDAY.
THE LATEST WATER VAPOR IMAGERY SHOWS A CLOSED UPPER LOW CIRCULATING
OVER FAR SOUTHEAST IDAHO WITH A DEEPENING SURFACE LOW
DOWNSTREAM...POSITIONED OVER NORTHEAST WYOMING. A WARM FRONT
EXTENDED FROM THIS LOW AND WAS DRAPED ALONG THE SOUTHERN BORDER.
WITH THIS WARM FRONT REMAINING JUST SOUTH OF OUR BORDER
TONIGHT/SUNDAY...AND THE UPPER LOW CATCHING UP WITH THE SURFACE
LOW AND BECOMING A VERTICALLY STACKED SYSTEM OVER CENTRAL SOUTH
DAKOTA...A WELL DEFINED DEFORMATION ZONE SETS UP OVER ALL OF
CENTRAL AND SOUTHERN NORTH DAKOTA LATER TONIGHT THROUGH SUNDAY.
FORCING/VERTICAL MOTION PER Q-VECTOR DIVERGENCE FIELD AND STEEP
MID LEVEL LAPSE RATES APPEAR MAXIMIZED BETWEEN INTERSTATE 94 AND
JUST SOUTH OF HIGHWAY 2. THIS SHOULD SET THE STAGE FOR PERIODS OF
HEAVIER RAINFALL AND HIGHEST RAINFALL TOTALS THROUGH SUNDAY.
EXPECT BETWEEN 1 AND 1.4 INCHES OF TOTAL RAINFALL THROUGH SUNDAY
NIGHT BETWEEN INTERSTATE 94 AND HIGHWAY 2.
THUNDERSTORM POTENTIAL REMAINS ELEVATED THROUGH THE PERIOD WITH
DECREASING CIN AS MOISTURE INCREASES THROUGH THE COLUMN AND
STEEPENING MID LEVEL LAPSE RATES. BEST CHANCES WILL BE TONIGHT
THROUGH SUNDAY MORNING...WITH SOUNDINGS BECOMING SATURATED AND
SHOWING RELATIVELY SKINNY OR NO CAPE FIELD. ENVIRONMENT SHOULD
TRANSITION MORE TOWARDS A HEAVY RAIN VERSUS CONVECTIVE IN NATURE.
SPC HAS MAINTAINED THE MARGINAL RISK FOR SEVERE THUNDERSTORMS IN
THE FAR SOUTHWEST TONIGHT. THINKING IS CONVECTION WOULD BEGIN AFTER
03Z PER LATEST HRRR AND GRADUALLY INCREASE OVERNIGHT INTO MID
MORNING SUNDAY.
GUSTY NORTHEAST WINDS WILL CONTINUE TONIGHT THROUGH SUNDAY ACROSS
ALL OF WESTERN AND CENTRAL NORTH DAKOTA. THE STRONGEST WINDS ARE
FORECAST ALONG AND NORTH OF HIGHWAY 2...WITH THE TURTLE MOUNTAINS
PINPOINTED FOR THE HIGHEST SUSTAINED WINDS OF AROUND 30 MPH AND
GUSTS TO 45 MPH. FUTURE SHIFTS CAN RE-EVALUATE FOR A POSSIBLE WIND
ADVISORY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 313 PM CDT SAT APR 23 2016
THE VERTICALLY STACKED SYSTEM CONTINUES TO SLOWLY SHIFT EAST
SUNDAY NIGHT AND MONDAY WITH A GRADUAL DECREASE IN POPS. HOWEVER
THE ECMWF HAS BEEN CONSISTENTLY ADVERTISING HIGHER QPF AND COLDER
AIR ESPECIALLY ALONG AND SOUTH OF INTERSTATE 94 MONDAY. THUS HAVE
TRENDED POPS BETWEEN CHC/LIKELY WITH MOSTLY RAIN AND A LITTLE BIT
OF SNOW EXPECTED. SNOWFALL ACCUMULATIONS OF A COUPLE TENTHS POSSIBLE
SUNDAY NIGHT ACROSS THE WEST.
ANOTHER ROUND OF PRECIPITATION IS POSSIBLE TUESDAY NIGHT THROUGH
WEDNESDAY NIGHT MAINLY ACROSS SOUTHERN NORTH DAKOTA. THE GFS AND
ECMWF CONTINUE TO BE AT ODDS IF THIS WILL OCCUR. THE GFS HAS BEEN
CONSISTENTLY SHOWING THE ABOVE...WHILE THE ECMWF IS NOT AS FAR
NORTH WITH THE PRECIPITATION SHIELD.
A BREAK IN THE PRECIPITATION THREAT IS POSSIBLE THURSDAY AND FRIDAY.
ANOTHER WET PERIOD SATURDAY BUT THE GFS AND ECMWF DIFFER ON PLACEMENT
OF THE PRECIPITATION AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1225 AM CDT SUN APR 24 2016
MAIN HAZARDS TO AVIATION WILL BE GUSTY EAST WINDS AND A DEVELOPING
RAIN THAT WILL USHER IN WIDESPREAD IFR CONDITIONS SUNDAY. SURFACE
LOW PRESSURE ACROSS WESTERN SOUTH DAKOTA WILL MAINTAIN A STRONG
EASTERLY WIND FLOW THROUGH THE PERIOD. VFR EXPECTED THROUGH
08Z...THEN RAPIDLY DETERIORATING CONDITIONS TO IFR IN RAIN AND BR
AFTER 08Z. ISOLATED THUNDERSTORMS ARE POSSIBLE NEAR KBIS/KDIK/KJMS
THIS MORNING...BUT CONFIDENCE AND COVERAGE IS NOT HIGH ENOUGH TO
WARRANT ANYTHING OTHER THAN A VICINITY MENTION.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AJ
SHORT TERM...KS
LONG TERM...KS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1006 PM EDT MON APR 25 2016
.SYNOPSIS...
WEAKENING LOW PRESSURE WILL MOVE EAST ALONG A STATIONARY
FRONT NEAR LAKE ERIE LATE TONIGHT INTO TUESDAY PULLING THE FRONT
SOUTH OF THE OHIO RIVER BY TUESDAY NIGHT. ANOTHER LOW WILL MOVE OUT
OF THE PLAINS WEDNESDAY NIGHT AND SLOWLY MOVE UP THE OHIO RIVER
THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
UPDATE...FOLLOWED THE HRRR PROGRESSION OF THE CONVECTION TO OUR
WEST WHICH DROPS IT SOUTHEAST ACROSS THE AREA OVERNIGHT. SREF
AGREES. HAVE ADJUSTED POPS TO SHOW A LINE/AREA OF CONVECTION
SAGGING SOUTHEAST WITH LIKELY POPS. CONTINUED WITH LOWER THUNDER
CHANCES AS CONVECTION SHOULD BE WEAKENING AS TO DROPS THROUGH. NO
OTHER BIG CHANGES.
ORIGINAL...WARM FRONT WILL SLOWLY LIFT NORTHWARD THROUGH THE
EVENING WITH UNCERTAINTY ABOUT IF IT WILL BE LIFTING ACROSS LAKE
ERIE. MOISTURE LEVELS ARE INCREASING BUT REMAINS RATHER SHALLOW.
THIS WILL MAKE IT DIFFICULT FOR ANY SHOWERS/THUNDER TO DEVELOP
ALONG THE WARM FRONT/WEAK LAKE BOUNDARY INTERACTION ACROSS THE
NORTHEAST PORTION OF THE COUNTY WARNING AREA. WILL STILL KEEP A
SLIGHT CHANCE/CHANCE MENTION FOR THIS AREA DURING THE EARLY
EVENING. CURRENT THINKING IS THAT THE CHANCES OF
SHOWERS/THUNDERSTORMS WILL NOT INCREASE UNTIL AFTER DARK AS THE
COLD FRONT MOVES TOWARD NW OHIO. THE LOW IS WEAKENING AS IT MOVES
EASTWARD OVERNIGHT WHICH SHOULD SLOW THE EASTWARD MOVEMENT OF THE
COLD FRONT. THE FRONT MAY BE ABOUT HALF WAY ACROSS THE COUNTY
WARNING AREA BY 12Z. THE COVERAGE OF THE SHOWERS AND THUNDERSTORMS
REMAINS UNCERTAIN WITH THE BEST COVERAGE OCCURRING ACROSS THE
NORTHEAST CWA. WE WILL NEED TO MONITOR THE CONVECTION THAT
DEVELOPS NEAR CHICAGO IN CASE IT SENDS A SIGNIFICANT OUTFLOW
BOUNDARY TOWARDS WESTERN OHIO.
IT WILL BE A WARM NIGHT WITH LOWS IN THE 50S. SLIGHTLY COOLER NEAR
THE LAKE.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
COLD FRONT WILL SLOWLY CROSS THE AREA THROUGH MONDAY MORNING. AS
THE WEAKENING LOW MOVES ACROSS THE REGION INTO CENTRAL PA TUESDAY
AFTERNOON WINDS WILL BECOME NORTHERLY PUSHING THE MOISTURE AND
WARMTH SOUTHWARD. HIGH PRESSURE WILL RIDGE INTO THE AREA FROM
CENTRAL CANADA ON WEDNESDAY KEEPING A FRONTAL BOUNDARY DOWN NEAR
THE OHIO RIVER VALLEY. THIS BOUNDARY WILL LIFT BACK TOWARD
NORTHERN OHIO AND NW PA WEDNESDAY NIGHT INTO THURSDAY WITH RAIN
CHANCES INCREASING FROM THE SOUTHWEST TO THE NORTHEAST. IT MAY
TAKE WELL INTO THURSDAY AFTERNOON FOR NW PA TO SEE ANY OF THE
RAIN. LOW PRESSURE THURSDAY AFTERNOON AND EVENING SHOULD TRACK
EASTWARD ALONG THE FRONTAL BOUNDARY THAT MAY LIFT AS FAR
NORTHWARD AS CENTRAL OHIO.
AFTER MORNING/EARLY AFTERNOON HIGHS ON TUESDAY THE TREND WILL BE
DOWNWARD. HIGHS WEDNESDAY AND THURSDAY SHOULD REMAIN IN THE 50S
NORTH AND 60S SOUTH. COLDEST NEAR THE LAKE WITH UPPER 40S
POSSIBLE.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
LONG TERM BEGINS ON FRIDAY AND MODELS ARE IN GOOD AGREEMENT ON AN
UPPER LEVEL SHORTWAVE TROUGH THAT WILL MOVE THROUGH THE GREAT LAKES
REGION. A WEAK SURFACE LOW PRESSURE SYSTEM ASSOCIATED WITH THIS
TROUGH WILL MEANDER EASTWARD ON FRIDAY BRINGING SLIGHT CHANCE TO
CHANCE POPS TO THE REGION THROUGH FRIDAY EVENING. ON SATURDAY MODELS
SHOW SOME UPPER LEVEL RIDGING BUILDING BEHIND THE TROUGH AND ALLOW
FOR A BREAK IN PRECIPITATION CHANCES FOR SATURDAY. GFS AND ECMWF
VARY ON THE INTENSITY OF THE RIDGE AND THE TIMING OF THE FOLLOWING
UPPER LEVEL TROUGH. THE GFS HAS A WEAKER RIDGE ON SATURDAY THAT
GIVES WAY TO A WEAK SHORTWAVE TROUGH BY MONDAY. ECMWF HAS A HIGHER
AMPLITUDE RIDGE ON SATURDAY BUT THE FOLLOWING TROUGH IS STRONGER AND
BECOMES CUT OFF OVER THE GREAT LAKES. GIVEN DIFFERING SOLUTIONS
BIASED MORE TOWARDS THE ECMWF AS GFS HAS NOT DONE AS WELL HANDLING
THE PRESENT WEATHER. THUS HAVE INCREASED POPS FOR SUNDAY AND MONDAY
AND LEFT A SLIGHT CHANCE OF THUNDER FOR SUNDAY AS AIRMASS COULD BE
MODESTLY UNSTABLE.
TEMPERATURES THROUGH THE PERIOD WILL BE AT OR BELOW CLIMATOLOGY.
LONG TERM LOOKS ACTIVE WITH CLOUDS AND RAIN WITH WINDS PREDOMINATELY
OUT OF THE NORTH/NORTHEAST...ALL OF WHICH WOULD PROMOTE TEMPERATURES
TO BE ON THE COOLER SIDE.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
STATIONARY FRONT POSITIONED RIGHT ACROSS NORTHERN OHIO AND INTO NW
PA...OVERHEAD OF CLE IN FACT. SHOWERS AND A FEW THUNDERSTORMS HAVE
BEEN FIRING OFF OF THIS NEAR CLE AND TO THE EAST. EXPECT THIS
ACTIVITY TO LAST ANOTHER COUPLE OF HOURS. THE FRONT SHOULD DRIFT
NORTH AS A WAVE OF LOW PRESSURE RIDES ALONG THE FRONT OVERNIGHT.
SHOWERS/THUNDERSTORMS ACROSS LAKE MICHIGAN EXPECTED TO CONGEAL AND
MOVE ACROSS NORTHERN OHIO DURING THE OVERNIGHT HOURS. IT WILL BE
IN A WEAKENING STATE BY THIS POINT AND NOT SURE THE AMOUNT OF
THUNDER THAT WILL TAKE PLACE. HAVE TS TEMPO FOR TOL/FDY AND THE
MENTION OF VCTS FOR CLE. THEN WEDNESDAY AS THE FRONT SINKS BACK
SOUTHWARD AFTER THAT WAVE PASSES...MVFR CEILINGS WILL OVERSPREAD
THE AREA...POSSIBLY SOME IFR FOR NE OH/NW. THIS WILL LIKELY LINGER
FOR MUCH IF NOT ALL OF WEDNESDAY THROUGH 00Z THU. SOUTHWEST WINDS
FOR ALL SOUTH OF THE FRONT WILL SHIFT TO THE NORTH FOR WEDNESDAY
AT A STEADY 15 KNOTS OR SO.
OUTLOOK...NON-VFR LATE WEDNESDAY NIGHT THROUGH FRIDAY...AND
POSSIBLY AGAIN ON SATURDAY.
&&
.MARINE...
A WARM FRONT INTO CENTRAL OHIO WILL LIFT TO NEAR ERIE LAKESHORE THIS
EVENING AND THEN STALL. LOW PRESSURE SYSTEM IN IOWA WILL RIDE ALONG
THE BOUNDARY ACROSS OHIO OVERNIGHT. THE SYSTEM WILL PUSH SOUTHEAST
OF THE AREA TUESDAY...DRAGGING A COLD FRONT ACROSS THE AREA. SMALL
CRAFT ADVISORY POSSIBLE SOMETIME TUESDAY INTO TUESDAY NIGHT AS THE
NORTHEAST FLOW OVER THE LAKE INCREASES TO 10 TO 20 KNOTS BEHIND THE
SYSTEM. EAST TO NORTHEAST WINDS WILL CONTINUE ON THE LAKE INTO NEXT
WEEKEND AS HIGH PRESSURE BECOMES ESTABLISHED OVER CENTRAL CANADA.
WINDS WILL INCREASE THURSDAY AS LOW PRESSURE MOVES ACROSS THE OHIO
VALLEY. WIND SPEEDS WILL DEPEND UPON HOW FAR NORTH THE LOW TRACKS.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MULLEN
NEAR TERM...TK/MULLEN
SHORT TERM...MULLEN
LONG TERM...SEFCOVIC
AVIATION...OUDEMAN
MARINE...SEFCOVIC
AREA FORECAST DISCUSSION
NWS Tulsa OK
645 PM CDT MON APR 25 2016
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
MVFR ceilings will develop again late tonight and will likely
persist through most of the day Tuesday. South winds will become
gusty by Tuesday afternoon. There is a chance that thunderstorms
will begin to affect the northeast Oklahoma sites by the very end
of the forecast period, but will hold off on the mention of them
at this time.
&&
.PREV DISCUSSION... /ISSUED 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.
&&
.TSA Watches/Warnings/Advisories...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...05
AREA FORECAST DISCUSSION
NWS PORTLAND OR
222 PM PDT SUN APR 24 2016
.SYNOPSIS...UNSETTLED WEATHER IN PLACE THIS AFTERNOON WITH A MIX OF
CLOUDS AND SUNBREAKS...PLENTY OF SHOWERS...SOME WITH SMALL HAIL
AND/OR A STRAY RUMBLE OF THUNDER. COOL AIR ALOFT HAS ALSO LOWERED THE
SNOW LEVEL TO NEAR THE CASCADE PASSES...WHERE A COUPLE MORE INCHES
OF SNOW ARE POSSIBLE THROUGH MONDAY. SNOW LEVELS WILL DROP A LITTLE
FURTHER TONIGHT AS THE BULK OF THE COLD AIR ALOFT SWINGS THROUGH THE
REGION. HIGHER PRESSURE WILL BUILD OFFSHORE FOR LESS SHOWER COVERAGE
MONDAY THEN DRIER WEATHER MONDAY NIGHT INTO TUESDAY. NEXT CHANCE FOR
SHOWERS COMES TUE NIGHT AND WED AS A SPLITTING SYSTEM APPROACHES THE
WEST COAST. THE MODELS ARE TRENDING DRIER FOR LATER NEXT WEEK AND
NEXT WEEKEND AS A FLAT UPPER LEVEL RIDGE OF HIGH PRESSURE DEVELOPS
OFFSHORE.
&&
.SHORT TERM...TONIGHT THROUGH WEDNESDAY...CLASSIC SPRING UNSETTLED
WEATHER PATTERN IN PLACE TODAY...WITH A COLD POOL ALOFT NEAR THE
OREGON COAST. WITHIN THE CORE OF THE COLD POOL...20Z RAP ANALYSIS
STILL SHOWS 500 MB TEMPS AS LOW AS -33 DEG C...PLENTY COLD TO SUPPORT
CONVECTION AND VERY ISOLATED THUNDERSTORMS. SHOWERS ARE FAIRLY
WIDESPREAD ACROSS SW WA/NW OR THIS AFTERNOON...WITH A FEW OF THE
STRONGER ONES PRODUCING PEA-SIZED HAIL AND/OR A LIGHTNING STRIKE OR
TWO. AS EXPECTED THE CELLS HAVE GENERALLY BEEN PULSE-TYPE WITH LITTLE
TO NO ORGANIZATION. MOST ARE ONLY LASTING THE FIRST UPDRAFT CYCLE
BEFORE COLLAPSING BACK DOWN ON THEMSELVES. THERE DOES APPEAR TO BE A
LOOSELY ORGANIZED LINE OF CONVECTION FROM HILLSBORO TO EUGENE...
MARCHING SLOWLY EASTWARD ACROSS THE WILLAMETTE VALLEY ALONG A WEAK
FRONTAL BOUNDARY ALOFT. WILL CONTINUE TO MONITOR THIS AREA...BUT IT
IS DOUBTFUL IT WILL DO MUCH OTHER THAN PRODUCE A COUPLE AREAS OF
SMALL HAIL AND A COUPLE STRAY LIGHTNING STRIKES. OTHERWISE EXPECT
SIMILAR MAINLY PULSE-TYPE SHOWERS TO CONTINUE UNTIL SUNSET BEFORE
DECREASING IN COVERAGE WITH THE LOSS OF SOLAR HEATING.
TEMPERATURES TODAY STAND IN SHARP CONTRAST TO WHAT THE REGION HAS
FELT FOR MUCH OF THE MONTH OF APRIL...WE MAY ACTUALLY END UP BELOW
NORMAL FOR THE DAY AS HIGHS STRUGGLE TO GET OUT OF THE 50S IN THE
LOWLANDS. SNOW LEVELS ARE DOWN NEAR THE CASCADE PASSES...BUT MOST OF
THE SNOW SEEMS TO BE MELTING EITHER ON CONTACT WITH THE ROADS OR
SHORTLY AFTERWARDS. WITHOUT THE FAIRLY STRONG LATE APRIL SUNSHINE...
SNOW SHOULD HAVE A LITTLE EASIER TIME ACCUMULATING ABOVE 3500 FT
TONIGHT. HEAVIER SNOW SHOWERS COULD PRODUCE A QUICK 1-2 INCH DUSTING
AT TIMES...BUT OTHERWISE SNOW AMOUNTS SHOULD BE FAIRLY LIGHT.
12Z GFS SHOWS THE CORE OF THE UPPER LOW OPENING UP INTO AN ENLONGATED
TROUGH TONIGHT AND MONDAY...MAKING VERY LITTLE INLAND PROGRESS.
REMNANT COOL AIR ALOFT WILL LIKELY TRIGGER A FEW SHOWERS MONDAY...
FAVORING THE HIGHER TERRAIN. 12Z NAM/GFS SOUNDINGS SUGGEST WARMER
AIR WILL ALREADY BE MOVING IN ALOFT BY AFTERNOON...KEEPING ANY
CONVECTION SHALLOWER THAN IT HAS BEEN THE PAST FEW DAYS. BY MONDAY
NIGHT UPPER LEVEL RIDGING WILL PROVIDE ENOUGH SUBSIDENCE TO BRING AN
END TO THE SHOWER ACTIVITY...YIELDING A MAINLY DRY AND SEASONABLE
LATE APRIL DAY TUESDAY.
MODELS SHOW GOOD AGREEMENT NOW THAT THE STRONG UPPER LOW DEVELOPING
SOUTH OF THE ALEUTIANS WILL REPLACE THE CURRENT GULF OF ALASKA
LOW...WHILE SENDING A SECONDARY UPPER TROUGH AND COLD FRONT TOWARD
THE U.S. WEST COAST. MODELS HAVE BEEN TRENDING TOWARD SPLITTING THIS
SYSTEM AS IT APPROACHES THE COAST...WITH A SIGNIFICANT AMOUNT OF ITS
ENERGY HEADING SOUTH TOWARD CALIFORNIA. STILL LOOKS LIKE IT WILL HOLD
TOGETHER ENOUGH TO BRING SOME RAIN TO THE DISTRICT TUE NIGHT/WED...
THOUGH AMOUNTS LOOK LIGHT. IMPACTS ARE EXPECTED TO BE MINIMAL IN THE
CASCADES...PERHAPS A LITTLE DUSTING UP TO 2 INCHES ABOVE PASS
LEVEL. WEAGLE
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY. A FEW RESIDUAL SHOWERS
MAY CONTINUE IN THE WEAKLY ONSHORE FLOW ALOFT WEDNESDAY NIGHT...
PARTICULARLY IN THE CASCADES SOUTH OF MT HOOD...BEFORE COMING TO AN
END BY EARLY SATURDAY. MEANWHILE...AN UPPER LEVEL RIDGE OVER THE
NORTHEAST PACIFIC STRENGTHENS AND BUILDS INTO THE PACIFIC NORTHWEST.
A PASSING SHORTWAVE MAY BRING SOME LIGHT SHOWERS TO THE NORTHERN
ZONES ON FRIDAY...BUT OTHERWISE A GENERALLY DRY END OF THE WEEK INTO
THE WEEKEND. HIGH TEMPERATURES GRADUALLY WARM AT THE END OF THE
WEEK...AND CLIMB A FEW DEGREES ABOVE SEASONAL NORMS BY NEXT
WEEKEND. CULLEN
&&
.AVIATION...AN UNSTABLE AIR MASS WILL CONTINUE TO BRING SCATTERED
SHOWERS TO THE FORECAST AREA TODAY AND TONIGHT. EXPECT PRIMARILY
VFR CONDITIONS BUT ISOLATED HEAVY SHOWERS OR THUNDERSTORMS MAY
BRING BRIEF MVFR OR LOWER CONDITIONS. SMALL HAIL CAN ALSO BE
EXPECTED WITH SHOWERS OR THUNDERSTORMS UNTIL ABOUT 02Z MON.
EXPECT PRIMARILY VFR THROUGH MON BUT THERE MAY BE LOCAL MVFR
CONDITIONS MON MORNING. THE CASCADES LIKELY REMAIN MOSTLY
OBSCURED TONIGHT UNDER LIGHT RAIN AND SNOW SHOWERS.
KPDX AND APPROACHES...PRIMARILY VFR CONDITIONS THROUGH TONIGHT.
WILL ALSO SEE A THREAT OF TSRA THRU 03Z MON WHICH MAY BRING BRIEF
MVFR CIGS AND VIS. /MH
&&
.MARINE...HIGH PRES TO THE WEST OF THE WATERS WILL MAINTAIN
NORTHWESTERLY WINDS ACROSS THE WATERS TONIGHT. WINDS ARE EXPECTED
TO REMAIN BELOW ADVISORY CRITERIA BUT STILL EXPECT GUSTS TO 20 KT
IN THE COOL UNSTABLE AIR MASS. WINDS EASE LATER TONIGHT AND MONDAY
AS THE HIGH PRES SHIFTS OVER THE WATERS. MODELS CONTINUE TO SHOW A
WEAKENING FRONT APPROACHING LATE TUE OR WED...BUT IMPACTS LOOK TO
REMAIN MINIMAL. WILL LIKELY SEE GUSTY NORTHERLY WINDS DEVELOP LATE
IN THE WEEK AS THERMAL LOW PRES BUILDS OVER NORTHERN CALIFORNIA
AND SOUTHERN OREGON. MODELS ALSO CONTINUE TO SHOW ANOTHER WEAK
FRONT MOVING ACROSS THE WATERS NEXT WEEKEND.
SEAS CURRENTLY AROUND 8 FT EARLY THIS MORNING...BUT WILL BUILD TO
AROUND 10 FT BY NOON TODAY AND CONTINUE THROUGH MONDAY. SEAS LOOK
TO FALL BELOW 10 FT MONDAY AFTERNOON AND REMAIN BELOW ADVISORY
CRITERIA THROUGH THURSDAY. /MH /64
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 3 PM PDT MONDAY
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR
OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 PM
THIS AFTERNOON TO 10 PM PDT THIS EVENING.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM TO
10 AM PDT MONDAY.
&&
$$
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THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS PORTLAND OR
1004 AM PDT SUN APR 24 2016
.SYNOPSIS...UNSETTLED WEATHER EXPECTED TODAY WITH A MIX OF CLOUDS AND
SUNBREAKS...PLENTY OF SHOWERS AND ISOLATED THUNDERSTORMS. COOL UPPER
LEVEL LOW IS MOVING ONSHORE INTO OREGON...DESTABILIZING THE AIR MASS
AND RESULTING IN THE UNSETTLED WEATHER. THE COOL AIR HAS ALSO DROPPED
THE SNOW LEVEL TO THE CASCADE PASSES...WHERE A COUPLE INCHES OF
ADDITIONAL SNOW ARE POSSIBLE THROUGH MONDAY. SNOW LEVELS WILL DROP A
LITTLE FURTHER TONIGHT AS THE BULK OF THE COLD AIR ALOFT SWINGS
THROUGH THE REGION. HIGHER PRESSURE WILL BUILD OFFSHORE FOR LESS
SHOWER COVERAGE MONDAY THEN DRIER WEATHER MONDAY NIGHT INTO TUESDAY.
NEXT CHANCE FOR SHOWERS COMES TUE NIGHT AND WED AS A SPLITTING SYSTEM
APPROACHES THE WEST COAST. THE MODELS ARE TRENDING DRIER FOR LATER
NEXT WEEK AND NEXT WEEKEND.
&&
.MORNING UPDATE...CLASSIC SPRING UNSETTLED WEATHER PATTERN SETTING UP
TODAY...WITH A COLD POOL ALOFT APPROACHING THE OREGON COAST. WITHIN
THE CORE OF THE COLD POOL...15Z RAP ANALYSIS SHOWS 500 MB TEMPS AS
LOW AS -33 DEG C...PLENTY COLD TO SUPPORT CONVECTION AND ISOLATED
THUNDERSTORMS. LATEST SATELLITE IMAGERY SHOWS A GOOD AMOUNT OF COLD
AIR CUMULUS OFFSHORE...WHILE LIGHTNING DETECTION SHOWS THE STRONGER
CELLS PRODUCING A HANDFUL OF LIGHTNING STRIKES. THE COLD POOL ALOFT
IS EXPECTED TO MODERATE SLIGHTLY WHILE APPROACHING THE COAST
TODAY...AND THE 12Z NAM NEVER QUITE BRINGS THE CORE OF THE COLD AIR
INLAND. ON THE OTHER HAND...VISIBLE SATELLITE IMAGERY SHOWS A FEW
SUNBREAKS WHICH WILL ENHANCE SURFACE HEATING AND INSTABILITY AS THE
DAY PROGRESSES. OVERALL IT APPEARS THE ENVIRONMENT ACROSS THE
FORECAST AREA WILL A FEW HEAVY SHOWERS...SOME SMALL HAIL...AND A
COUPLE THUNDERSTORMS TODAY. CELLS WILL PROBABLY HAVE DIFFICULTY
GETTING ORGANIZED GIVEN THE RATHER WEAK SHEAR PROFILE BELOW 500
MB...SO WE GENERALLY EXPECT PULSE-TYPE CELLS. CELLS COMING OFF THE
COAST RANGE WILL HAVE A LITTLE BETTER CHANCE AT ORGANIZATION DUE TO
TERRAIN-FORCED S-SW FLOW NEAR THE SURFACE VERSUS THE MORE WESTERLY
FLOW ABOVE 1 KM. WOULD NOT BE SURPRISED TO HEAR OF A COLD CORE FUNNEL
OR TWO THIS AFTERNOON...PATTERN RECOGNITION SUGGESTS MANY OF OUR
FUNNEL CLOUD CASES OCCUR WHEN A COLD CORE LOW IS MOVING ONSHORE. AS
USUAL...IT IS HIGHLY UNLIKELY ANY COLD-CORE FUNNELS WOULD TOUCH THE
GROUND AS A TORNADO SHOULD THEY DEVELOP.
OTHERWISE THE FORECAST LOOKS TO BE IN GOOD SHAPE...WARMED UP TEMPS
SLIGHTLY TODAY AND MONDAY AS WE SHOULD BE ABLE TO GET INTO THE UPPER
50S OR NEAR 60 WITH SUNBREAKS AND 850 MB TEMPS NEAR ZERO DEG C. SNOW
LEVELS APPEAR TO BE NEAR CASCADE PASS LEVEL PER ODOT WEBCAMS...MOST
OF THE SNOW SEEMS TO BE MELTING EITHER ON CONTACT WITH THE ROADS OR
SHORTLY AFTERWARDS. HEAVIER SNOW SHOWERS IN THE CASCADES COULD
PRODUCE A QUICK 1-2 INCH DUSTING AT TIMES...BUT OTHERWISE SNOW
AMOUNTS SHOULD BE FAIRLY LIGHT. WEAGLE
/PREV DISC ISSUED 321 AM PDT SUN APR 24 2016/
.SHORT TERM...A COLD FRONT MOVED THROUGH SOUTHWEST WASHINGTON AND
NORTHWEST OREGON OVERNIGHT. ONSHORE FLOW BEHIND THE FRONT WILL SPREAD
MORE SHOWERS ONSHORE TODAY. THE ASSOCIATED PARENT UPPER LOW IS TO
APPROACH THE COAST TODAY...THEN DIG SOUTH TOWARD THE GREAT BASIN
TONIGHT AND TUESDAY. THIS SHOULD KEEP DECENT SHOWER ACTIVITY OVER THE
FORECAST AREA TODAY...WITH SNOW LEVELS BELOW THE CASCADE PASSES.
THERE WILL LIKELY BE ACCUMULATING SNOW IN THE PASSES...BUT BELOW SNOW
ADVISORY CRITERIA.
THE COOLER AIR ALOFT SPREADING IN TODAY WITH THE UPPER LOW WILL
RESULT IN A CHANCE OF THUNDER...ESPECIALLY THIS AFTERNOON AND
EVENING. ANY THUNDERSTORMS THAT DO DEVELOP WILL HAVE SOME HAIL...
GUSTY WINDS...AND HEAVY SHOWERS WITH THEM. THE COOLER AIR WILL ALSO
KEEP HIGHS INLAND TODAY IN THE 55 TO 60 RANGE.
AS THE LOW DIGS SOUTH...SHOWER COVERAGE WILL DECREASE LATER TONIGHT
AND MONDAY...THOUGH THE SHOWERS WILL NOT END DUE TO BEING ON THE
CYCLONIC SIDE OF THE JET.
AN UPPER LEVEL RIDGE BRINGS DRYING TO THE AREA MONDAY NIGHT AND
TUESDAY. LOOK FOR SOME AREAS OF LOW CLOUDS AND PATCHY FOG DEVELOPING
LATER MONDAY NIGHT THROUGH TUESDAY MORNING...THEN BREAKING UP TUESDAY
AFTERNOON WITH INLAND TEMPS CLIMBING BACK INTO THE LOWER 60S.
TOLLESON
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
EXPECT INCREASING CLOUDS AGAIN TUESDAY NIGHT WITH THE NEXT FRONTAL
SYSTEM OFFSHORE AND APPROACHING THE COAST. FORECAST MODELS SUGGEST A
SPLITTING SYSTEM WITH THE MAJORITY OF THE ENERGY MOVING TO THE SOUTH
OF THE FORECAST AREA. AS A RESULT...HAVE INCREASED POPS OVER THE
SOUTHERN PORTIONS OF THE FORECAST AREA FOR LATE TUESDAY NIGHT THROUGH
WEDNESDAY TO CHANCE RANGE...TAPERING OFF TO SLIGHT CHANCE FOR THE
NORTHERN ZONES. THE GENERAL TREND IN THE MODEL GUIDANCE SUPPORTS THIS
UPPER LOW DEEPENING OVER THE GREAT BASIN OR FOUR CORNERS REGION FOR
THE SECOND HALF OF NEXT WEEK...WITH A WEAK RIDGE SETTING UP OVER THE
REGION. A FEW SHORTWAVES MAY ATTEMPT TO PASS OVER THE TOP OF THIS
RIDGE. FOR NOW...EXPECT THAT THE EXTENDED PERIOD WILL GENERALLY BE
MARKED BY MORE PERIODS OF DRY THAN WET BUT THE TIMING OF THE PERIODS
OF PRECIPITATION WILL LIKELY BE REFINED IN THE COMING DAYS. CULLEN
&&
.AVIATION...AN UNSTABLE AIR MASS WILL CONTINUE TO BRING SCATTERED
SHOWERS TO THE FORECAST AREA TODAY AND TONIGHT. EXPECT PRIMARILY
VFR CONDITIONS THIS AFTERNOON...BUT ONSHORE FLOW MAY KEEP A MIX
OF CIGS AT THE COAST. THE UNSTABLE AIR MASS WILL ALSO BRING A
THREAT OF TSRA AND ISOLATED MVFR OR IFR CONDITIONS ACROSS THE
REGION THROUGH THIS EVENING. WILL LIKELY SEE CIGS BECOME PRIMARILY
MVFR ALONG THE COAST LATE TONIGHT WITH THE INTERIOR REMAINING VFR.
THE CASCADES LIKELY REMAIN OBSCURED TODAY AND TONIGHT UNDER LIGHT
RAIN AND SNOW SHOWERS.
KPDX AND APPROACHES...PRIMARILY VFR CONDITIONS THROUGH TONIGHT.
WILL ALSO SEE A THREAT OF TSRA BETWEEN 24/18Z AND 25/03Z WHICH MAY
BRING BRIEF MVFR CIGS AND VIS. /MH /64
&&
.MARINE...HIGH PRES TO THE WEST OF THE WATERS WILL MAINTAIN
NORTHWESTERLY WINDS ACROSS THE WATERS TODAY. WINDS ARE EXPECTED TO
REMAIN BELOW ADVISORY CRITERIA BUT STILL EXPECT GUSTS TO 20 KT IN
THE COOL UNSTABLE AIR MASS. WINDS EASE LATER TONIGHT AND MONDAY AS
THE HIGH PRES SHIFTS OVER THE WATERS. MODELS CONTINUE TO SHOW A
WEAKENING FRONT APPROACHING LATE TUE OR WED...BUT IMPACTS LOOK TO
REMAIN MINIMAL. WILL LIKELY SEE GUSTY NORTHERLY WINDS DEVELOP LATE
IN THE WEEK AS THERMAL LOW PRES BUILDS OVER NORTHERN CALIFORNIA
AND SOUTHERN OREGON. MODELS ALSO CONTINUE TO SHOW ANOTHER WEAK
FRONT MOVING ACROSS THE WATERS NEXT WEEKEND.
SEAS CURRENTLY AROUND 8 FT EARLY THIS MORNING...BUT WILL BUILD TO
AROUND 10 FT BY NOON TODAY AND CONTINUE THROUGH MONDAY. SEAS LOOK
TO FALL BELOW 10 FT MONDAY AFTERNOON AND REMAIN BELOW ADVISORY
CRITERIA THROUGH THURSDAY. /MH /64
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 3 PM PDT MONDAY
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR
OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 10 AM
PDT THIS MORNING.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 PM
THIS AFTERNOON TO 10 PM PDT THIS EVENING.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1200 AM EDT TUE APR 26 2016
.SYNOPSIS...
LOW PRESSURE OVER THE LAKE MICHIGAN WILL TRACK THROUGH THE
SOUTHERN GREAT LAKES TONIGHT AND OVER NRN PA/WRN NY STATE ON
TUESDAY. IT WILL PUSH A COLD FRONT THROUGH THE AREA ON TUESDAY AND
TO THE SOUTH OF THE COMMONWEALTH BY WEDNESDAY MORNING. ANOTHER
AREA OF LOW PRESSURE TRACK SOUTH OF PENNSYLVANIA THURSDAY INTO
FRIDAY.
&&
.NEAR TERM /UNTIL 8 AM TUESDAY MORNING/...
NICE CELL W/THUNDER AND PERHAPS A WIND GUST TO 30-35MPH IN IT
ROLLING THRU ELK CO. THIS MAY BE THE MCV OF THE CURRENT CLUSTER OF
SH/TSRA AS IT SEEMS TO HAVE A VERY BROAD ROTATION TO IT. FORECAST
IS ROLLING ALONG NICELY...TOO. EXPECT THINGS TO MAINTAIN OR WEAKEN
SLIGHTLY AS THEY MAY START TO FEED MORE OFF OF THE VERY DRY LLVL
AIR OVER CENTRAL PA RATHER THAN THE UPSTREAM /SW/ VALUES WHICH ARE
INTO THE 50S. SHOWERS DO STRETCH BACK INTO NRN OH AS EXPECTED AND
WILL PLAY SOME CHC POPS ACROSS THE NRN TIER FOR THE REST OF THE
NIGHT. TEMPS SHOULD REMAIN VERY MILD OVERNIGHT.
PREV...
A FEW CLOUD FLASHES AND CGS INSIDE THE CONVECTION OVER CRAWFORD
CO...SO FEEL SAFE LEAVING MENTIONS OF THUNDER IN FOR THE NIGHT.
GOOD INFLOW FROM THE SW TO THESE SHOWERS - BUT THE DEWPOINTS ARE
ONLY 45-50F OVER SRN OH/SWRN PA. WITH THE QUICK MOTION AND LOW
MOISTURE - THESE SHOULD NOT EVEN MAKE HEAVY RAIN FOR MORE THAN A
MINUTE AT ANY LOCATION. HOWEVER...REPEATED CELLS PASSING OVERHEAD
COULD TAKE QPF INTO THE QUARTER TO HALF INCH ACROSS THE NRN TIER
BY MORNING. HRR AND RAP PROPAGATE THE FIRST BATCH OF PRECIP TO
THE EAST STEADILY. A SECOND AND PERHAPS THIRD WAVE OF
SHOWERS/TSTORMS IS FCST TO DEVELOP OVER NRN OH AND CROSS THE STATE
- MAINLY NORTH OF INTERSTATE 80 - LIKELY SKIRTING DRY/HAPPY
VALLEY.
PREV...
TRANSLUCENT MID LEVEL DECK INCREASING OVER CENTRAL PA EARLY THIS
AFTERNOON. MAIN BAROCLINIC ZONE AND OPAQUE CLOUDINESS RESIDE
NORTH OF THE PA/NY BORDER...AND MOST AREAS WILL REMAIN MOSTLY
SUNNY THROUGH THE THINK MID/HIGH CLOUD DECK. TEMPS QUITE WARM AND
RANGE FROM THE UPPER 60S THROUGH THE 70S ELSEWHERE.
HIGH LEVEL MOISTURE WILL CONTINUE TO INCREASE TONIGHT AHEAD OF AN
APPROACHING SHORTWAVE AND ASSOCIATED LOW PRESSURE TRACKING THROUGH
THE SOUTHERN GLAKS. POTENT SHORTWAVE AND ASSOC LL JET WILL BRING
A GOOD CHC OF SHOWERS AND ISOLD TSRA OVERNIGHT...PRIMARILY ACROSS
THE NORTHERN HALF OF THE STATE. STILL TIMING BEST CHANCE OF RAIN
BETWEEN 02Z TO 10Z TIMEFRAME. DIMINISHING CHC OF SHOWERS LINGERS
AFTERWARDS AS FRONT SAGS SOUTHWARD ACROSS THE COMMONWEALTH.
NORTHERN AND CENTRAL AREAS MAY SEE BETWEEN A QUARTER AND A THIRD
OF AN INCH OF RAIN...OUTLIERS NEAR ONE HALF...WHICH IS MUCH NEEDED
GIVEN RECENT DRYNESS.
&&
.SHORT TERM /8 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
SFC FRONTAL WAVE TRACKS ALONG THE PA/NY BORDER TUESDAY MORNING...
BEFORE SAGGING SOUTHWARD AS COLD FRONT SETTLES ACROSS THE
COMMONWEALTH. EXTREME SOUTHERN TIER REMAINS IN SPC MRGL OUTLOOK
WITH PERHAPS ENOUGH CAPE TO PRODUCE A STRONG STORM OR TWO BEFORE
THE FRONT SETTLES SOUTH OF THE MASON DIXON LINE TUE AFTERNOON.
MODELS SHOWING LOCAL PREFRONTAL 1000 J/KG CAPES IN THIS ALONG THE
MASON DIXON LINE TUE MORNING/AFTN.
COOL AIR REACHES THE NORTHWEST EARLY TUE...WITH HIGHS THERE ONLY
REACHING NEAR 60F. FARTHER SOUTH ANOTHER WARM DAY WILL BE SEEN
WITH HIGHS IN THE MID TO UPPER 70S FOR ONE MORE DAY ACROSS SOUTH
CENTRAL AND SOUTHEAST PA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
NOT A LOT OF CHANGE TO THIS PART OF THIS PACKAGE.
STILL LOOKS DRY ON WED...AS A NE FLOW OF DRY AIR BUILDS SOUTHWARD
FROM A LARGE HIGH OVER WESTERN HUDSON BAY.
A SYSTEM TRACKING SOUTH OF THE AREA ON THU WILL BRING SOME RAIN
AND COOL TEMPERATURES TO THE AREA.
A SECOND WEAK SYSTEM TRACKING SOUTH OF THE AREA OUT OF WV MAY
BRING SOME SHOWERS STILL ON FRIDAY. LEFT POPS IN.
STILL SOME HINTS OF A JET MAX DROPPING SE ON SAT...BUT REALLY
NO MOISTURE TO WORK WITH. THUS STILL EXPECT THE DAY TO BE DRY.
MID SHIFT HAD SOME SHOWERS IN FOR LATER ON SUNDAY. YESTERDAY THE
EC WAS TOO FAST...STILL THAT WAY TODAY. LEFT POPS IN BUT DID LOWER
SOME FOR SUNDAY AND SUNDAY NIGHT.
FOR SUNDAY NIGHT..DID EDGE TEMPERATURES DOWN A LITTLE.
LOOKS WET AND COOL FOR MONDAY. DID NOT GO QUITE AS HIGH AS
THE SUPERBLEND WITH THE POPS.
CLEARING OUT LATER MONDAY NIGHT.
OVERALL A PATTERN THAT FAVORS WETTER AND COOLER WEATHER
THAN WE HAVE HAD LATELY.
&&
.AVIATION /04Z TUESDAY THROUGH SATURDAY/...
SHOWERS AND THUNDERSTORMS CONTINUE TO MOVE EASTWARD...HOWEVER THE
STORMS CONTINUE TO FADE AS THEY REACH THE DRIER AIR TO THE EAST.
THERE WILL BE ANOTHER PERIOD OF STORMS OVERNIGHT TOWARDS THE
MORNING...ALONG A FRONTAL BOUNDARY THAT WILL PASS THROUGH THE
REGION WEST TO EAST BEGINNING AROUND 09Z. THAT LINE WILL BRING
MVFR TO POSSIBLE IFR CIGS TO BFD...JST...UNV AND AOO. WITH MVFR
POSSIBLE THE REST OF THE TAF SITES. THOUGH THE SYSTEM WILL BE
DRIER AS IT REACHES THE SOUTHEASTERN TAF SITES. THERE STILL
REMAINS A CHANCE FOR THUNDERSTORMS ACROSS SOUTHERN PA TUE
AFTERNOON. THE OTHER AVIATION CONCERN IS LOW LEVEL WIND SHEAR OUT
AHEAD OF THE LINE...AND HAVE PUT LLWS FOR AOO...JST...BFD AND UNV
BETWEEN 09Z TO 14Z.
OUTLOOK...
WED...NO SIG WX EXPECTED.
THU-FRI...MVFR WITH SHRA LIKELY.
SAT...FAIR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DANGELO/DEVOIR
SHORT TERM...DEVOIR
LONG TERM...MARTIN
AVIATION...DEVOIR/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1010 PM EDT MON APR 25 2016
.SYNOPSIS...
LOW PRESSURE OVER THE LAKE MICHIGAN WILL TRACK THROUGH THE
SOUTHERN GREAT LAKES TONIGHT AND OVER NRN PA/WRN NY STATE ON
TUESDAY. IT WILL PUSH A COLD FRONT THROUGH THE AREA ON TUESDAY AND
TO THE SOUTH OF THE COMMONWEALTH BY WEDNESDAY MORNING. ANOTHER
AREA OF LOW PRESSURE TRACK SOUTH OF PENNSYLVANIA THURSDAY INTO
FRIDAY.
&&
.NEAR TERM /UNTIL 8 AM TUESDAY MORNING/...
NICE CELL W/THUNDER AND PERHAPS A WIND GUST TO 30-35MPH IN IT
ROLLING THRU ELK CO. THIS MAY BE THE MCV OF THE CURRENT CLUSTER OF
SH/TSRA AS IT SEEMS TO HAVE A VERY BROAD ROTATION TO IT. FORECAST
IS ROLLING ALONG NICELY...TOO. EXPECT THINGS TO MAINTAIN OR WEAKEN
SLIGHTLY AS THEY MAY START TO FEED MORE OFF OF THE VERY DRY LLVL
AIR OVER CENTRAL PA RATHER THAN THE UPSTREAM /SW/ VALUES WHICH ARE
INTO THE 50S. SHOWERS DO STRETCH BACK INTO NRN OH AS EXPECTED AND
WILL PLAY SOME CHC POPS ACROSS THE NRN TIER FOR THE REST OF THE
NIGHT. TEMPS SHOULD REMAIN VERY MILD OVERNIGHT.
PREV...
A FEW CLOUD FLASHES AND CGS INSIDE THE CONVECTION OVER CRAWFORD
CO...SO FEEL SAFE LEAVING MENTIONS OF THUNDER IN FOR THE NIGHT.
GOOD INFLOW FROM THE SW TO THESE SHOWERS - BUT THE DEWPOINTS ARE
ONLY 45-50F OVER SRN OH/SWRN PA. WITH THE QUICK MOTION AND LOW
MOISTURE - THESE SHOULD NOT EVEN MAKE HEAVY RAIN FOR MORE THAN A
MINUTE AT ANY LOCATION. HOWEVER...REPEATED CELLS PASSING OVERHEAD
COULD TAKE QPF INTO THE QUARTER TO HALF INCH ACROSS THE NRN TIER
BY MORNING. HRR AND RAP PROPAGATE THE FIRST BATCH OF PRECIP TO
THE EAST STEADILY. A SECOND AND PERHAPS THIRD WAVE OF
SHOWERS/TSTORMS IS FCST TO DEVELOP OVER NRN OH AND CROSS THE STATE
- MAINLY NORTH OF INTERSTATE 80 - LIKELY SKIRTING DRY/HAPPY
VALLEY.
PREV...
TRANSLUCENT MID LEVEL DECK INCREASING OVER CENTRAL PA EARLY THIS
AFTERNOON. MAIN BAROCLINIC ZONE AND OPAQUE CLOUDINESS RESIDE
NORTH OF THE PA/NY BORDER...AND MOST AREAS WILL REMAIN MOSTLY
SUNNY THROUGH THE THINK MID/HIGH CLOUD DECK. TEMPS QUITE WARM AND
RANGE FROM THE UPPER 60S THROUGH THE 70S ELSEWHERE.
HIGH LEVEL MOISTURE WILL CONTINUE TO INCREASE TONIGHT AHEAD OF AN
APPROACHING SHORTWAVE AND ASSOCIATED LOW PRESSURE TRACKING THROUGH
THE SOUTHERN GLAKS. POTENT SHORTWAVE AND ASSOC LL JET WILL BRING
A GOOD CHC OF SHOWERS AND ISOLD TSRA OVERNIGHT...PRIMARILY ACROSS
THE NORTHERN HALF OF THE STATE. STILL TIMING BEST CHANCE OF RAIN
BETWEEN 02Z TO 10Z TIMEFRAME. DIMINISHING CHC OF SHOWERS LINGERS
AFTERWARDS AS FRONT SAGS SOUTHWARD ACROSS THE COMMONWEALTH.
NORTHERN AND CENTRAL AREAS MAY SEE BETWEEN A QUARTER AND A THIRD
OF AN INCH OF RAIN...OUTLIERS NEAR ONE HALF...WHICH IS MUCH NEEDED
GIVEN RECENT DRYNESS.
&&
.SHORT TERM /8 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
SFC FRONTAL WAVE TRACKS ALONG THE PA/NY BORDER TUESDAY MORNING...
BEFORE SAGGING SOUTHWARD AS COLD FRONT SETTLES ACROSS THE
COMMONWEALTH. EXTREME SOUTHERN TIER REMAINS IN SPC MRGL OUTLOOK
WITH PERHAPS ENOUGH CAPE TO PRODUCE A STRONG STORM OR TWO BEFORE
THE FRONT SETTLES SOUTH OF THE MASON DIXON LINE TUE AFTERNOON.
MODELS SHOWING LOCAL PREFRONTAL 1000 J/KG CAPES IN THIS ALONG THE
MASON DIXON LINE TUE MORNING/AFTN.
COOL AIR REACHES THE NORTHWEST EARLY TUE...WITH HIGHS THERE ONLY
REACHING NEAR 60F. FARTHER SOUTH ANOTHER WARM DAY WILL BE SEEN
WITH HIGHS IN THE MID TO UPPER 70S FOR ONE MORE DAY ACROSS SOUTH
CENTRAL AND SOUTHEAST PA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
NOT A LOT OF CHANGE TO THIS PART OF THIS PACKAGE.
STILL LOOKS DRY ON WED...AS A NE FLOW OF DRY AIR BUILDS SOUTHWARD
FROM A LARGE HIGH OVER WESTERN HUDSON BAY.
A SYSTEM TRACKING SOUTH OF THE AREA ON THU WILL BRING SOME RAIN
AND COOL TEMPERATURES TO THE AREA.
A SECOND WEAK SYSTEM TRACKING SOUTH OF THE AREA OUT OF WV MAY
BRING SOME SHOWERS STILL ON FRIDAY. LEFT POPS IN.
STILL SOME HINTS OF A JET MAX DROPPING SE ON SAT...BUT REALLY
NO MOISTURE TO WORK WITH. THUS STILL EXPECT THE DAY TO BE DRY.
MID SHIFT HAD SOME SHOWERS IN FOR LATER ON SUNDAY. YESTERDAY THE
EC WAS TOO FAST...STILL THAT WAY TODAY. LEFT POPS IN BUT DID LOWER
SOME FOR SUNDAY AND SUNDAY NIGHT.
FOR SUNDAY NIGHT..DID EDGE TEMPERATURES DOWN A LITTLE.
LOOKS WET AND COOL FOR MONDAY. DID NOT GO QUITE AS HIGH AS
THE SUPERBLEND WITH THE POPS.
CLEARING OUT LATER MONDAY NIGHT.
OVERALL A PATTERN THAT FAVORS WETTER AND COOLER WEATHER
THAN WE HAVE HAD LATELY.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
LATEST RADAR HAS SHOWERS BEGINNING TO STREAM ACROSS THE NORTHERN
TIER OF COUNTIES IN CENTRAL PA. HOWEVER VFR CONDITIONS CONTINUE TO
DOMINATE THROUGH THE EARLY EVENING HOURS. LATEST HRRR BRINGS TWO
PORTIONS OF PRECIPITATION THROUGH THE REGION. THE FIRST YOU ARE
SEEING NOW AND WILL SPREAD THROUGH CENTRAL PA...AFFECTING
BFD...UNV AND IPT...WITH MVFR CIGS POSSIBLE. THE SECOND IS ALONG
THE FRONTAL BOUNDARY THAT WILL PASS BEGIN TO PASS THROUGH THE
REGION WEST TO EAST BEGINNING AROUND 09Z. THAT LINE WILL BRING
MVFR TO POSSIBLE IFR CIGS TO BFD...JST AND AOO. WITH MVFR POSSIBLE
THE REST OF THE TAF SITES. THOUGH THE SYSTEM WILL BE DRIER AS IT
REACHES THE SOUTHEASTERN TAF SITES. THERE STILL REMAINS A CHANCE
FOR THUNDERSTORMS ACROSS SOUTHERN PA TUE AFTERNOON.
THE OTHER AVIATION CONCERN IS LOW LEVEL WIND SHEAR OUT AHEAD OF
THE LINE...AND HAVE PUT LLWS FOR AOO...JST...BFD AND UNV BETWEEN
09Z TO 14Z.
OUTLOOK...
WED...NO SIG WX EXPECTED.
THU-FRI...MVFR WITH SHRA LIKELY.
SAT...FAIR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DANGELO/DEVOIR
SHORT TERM...DEVOIR
LONG TERM...MARTIN
AVIATION...DEVOIR/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
911 PM EDT MON APR 25 2016
.SYNOPSIS...
LOW PRESSURE OVER THE UPPER MIDWEST MONDAY AFTERNOON WILL TRACK
THROUGH THE SOUTHERN GREAT LAKES TONIGHT AND ALONG THE
PENNSYLVANIA NEW YORK ON TUESDAY BEFORE PUSHING A COLD FRONT SOUTH
OF THE COMMONWEALTH BY WEDNESDAY MORNING. ANOTHER AREA OF LOW
PRESSURE TRACK SOUTH OF PENNSYLVANIA THURSDAY INTO FRIDAY.
&&
.NEAR TERM /UNTIL 7 AM TUESDAY MORNING/...
A FEW CLOUD FLASHES AND CGS INSIDE THE CONVECTION OVER CRAWFORD
CO...SO FEEL SAFE LEAVING MENTIONS OF THUNDER IN FOR THE NIGHT.
GOOD INFLOW FROM THE SW TO THESE SHOWERS - BUT THE DEWPOINTS ARE
ONLY 45-50F OVER SRN OH/SWRN PA. WITH THE QUICK MOTION AND LOW
MOISTURE - THESE SHOULD NOT EVEN MAKE HEAVY RAIN FOR MORE THAN A
MINUTE AT ANY LOCATION. HOWEVER...REPEATED CELLS PASSING OVERHEAD
COULD TAKE QPF INTO THE QUARTER TO HALF INCH ACROSS THE NRN TIER
BY MORNING. HRR AND RAP PROPAGATE THE FIRST BATCH OF PRECIP TO
THE EAST STEADILY. A SECOND AND PERHAPS THIRD WAVE OF
SHOWERS/TSTORMS IS FCST TO DEVELOP OVER NRN OH AND CROSS THE STATE
- MAINLY NORTH OF INTERSTATE 80 - LIKELY SKIRTING DRY/HAPPY
VALLEY.
PREV...
TRANSLUCENT MID LEVEL DECK INCREASING OVER CENTRAL PA EARLY THIS
AFTERNOON. MAIN BAROCLINIC ZONE AND OPAQUE CLOUDINESS RESIDE
NORTH OF THE PA/NY BORDER...AND MOST AREAS WILL REMAIN MOSTLY
SUNNY THROUGH THE THINK MID/HIGH CLOUD DECK. TEMPS QUITE WARM AND
RANGE FROM THE UPPER 60S THROUGH THE 70S ELSEWHERE.
HIGH LEVEL MOISTURE WILL CONTINUE TO INCREASE TONIGHT AHEAD OF AN
APPROACHING SHORTWAVE AND ASSOCIATED LOW PRESSURE TRACKING THROUGH
THE SOUTHERN GLAKS. POTENT SHORTWAVE AND ASSOC LL JET WILL BRING
A GOOD CHC OF SHOWERS AND ISOLD TSRA OVERNIGHT...PRIMARILY ACROSS
THE NORTHERN HALF OF THE STATE. STILL TIMING BEST CHANCE OF RAIN
BETWEEN 02Z TO 10Z TIMEFRAME. DIMINISHING CHC OF SHOWERS LINGERS
AFTERWARDS AS FRONT SAGS SOUTHWARD ACROSS THE COMMONWEALTH.
NORTHERN AND CENTRAL AREAS MAY SEE BETWEEN A QUARTER AND A THIRD
OF AN INCH OF RAIN...OUTLIERS NEAR ONE HALF...WHICH IS MUCH NEEDED
GIVEN RECENT DRYNESS.
&&
.SHORT TERM /7 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
SFC FRONTAL WAVE TRACKS ALONG THE PA/NY BORDER TUESDAY MORNING...
BEFORE SAGGING SOUTHWARD AS COLD FRONT SETTLES ACROSS THE
COMMONWEALTH. EXTREME SOUTHERN TIER REMAINS IN SPC MRGL OUTLOOK
WITH PERHAPS ENOUGH CAPE TO PRODUCE A STRONG STORM OR TWO BEFORE
THE FRONT SETTLES SOUTH OF THE MASON DIXON LINE TUE AFTERNOON.
MODELS SHOWING LOCAL PREFRONTAL 1000 J/KG CAPES IN THIS ALONG THE
MASON DIXON LINE TUE MORNING/AFTN.
COOL AIR REACHES THE NORTHWEST EARLY TUE...WITH HIGHS THERE ONLY
REACHING NEAR 60F. FARTHER SOUTH ANOTHER WARM DAY WILL BE SEEN
WITH HIGHS IN THE MID TO UPPER 70S FOR ONE MORE DAY ACROSS SOUTH
CENTRAL AND SOUTHEAST PA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
NOT A LOT OF CHANGE TO THIS PART OF THIS PACKAGE.
STILL LOOKS DRY ON WED...AS A NE FLOW OF DRY AIR BUILDS SOUTHWARD
FROM A LARGE HIGH OVER WESTERN HUDSON BAY.
A SYSTEM TRACKING SOUTH OF THE AREA ON THU WILL BRING SOME RAIN
AND COOL TEMPERATURES TO THE AREA.
A SECOND WEAK SYSTEM TRACKING SOUTH OF THE AREA OUT OF WV MAY
BRING SOME SHOWERS STILL ON FRIDAY. LEFT POPS IN.
STILL SOME HINTS OF A JET MAX DROPPING SE ON SAT...BUT REALLY
NO MOISTURE TO WORK WITH. THUS STILL EXPECT THE DAY TO BE DRY.
MID SHIFT HAD SOME SHOWERS IN FOR LATER ON SUNDAY. YESTERDAY THE
EC WAS TOO FAST...STILL THAT WAY TODAY. LEFT POPS IN BUT DID LOWER
SOME FOR SUNDAY AND SUNDAY NIGHT.
FOR SUNDAY NIGHT..DID EDGE TEMPERATURES DOWN A LITTLE.
LOOKS WET AND COOL FOR MONDAY. DID NOT GO QUITE AS HIGH AS
THE SUPERBLEND WITH THE POPS.
CLEARING OUT LATER MONDAY NIGHT.
OVERALL A PATTERN THAT FAVORS WETTER AND COOLER WEATHER
THAN WE HAVE HAD LATELY.
&&
.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
LATEST RADAR HAS SHOWERS BEGINNING TO STREAM ACROSS THE NORTHERN
TIER OF COUNTIES IN CENTRAL PA. HOWEVER VFR CONDITIONS CONTINUE TO
DOMINATE THROUGH THE EARLY EVENING HOURS. LATEST HRRR BRINGS TWO
PORTIONS OF PRECIPITATION THROUGH THE REGION. THE FIRST YOU ARE
SEEING NOW AND WILL SPREAD THROUGH CENTRAL PA...AFFECTING
BFD...UNV AND IPT...WITH MVFR CIGS POSSIBLE. THE SECOND IS ALONG
THE FRONTAL BOUNDARY THAT WILL PASS BEGIN TO PASS THROUGH THE
REGION WEST TO EAST BEGINNING AROUND 09Z. THAT LINE WILL BRING
MVFR TO POSSIBLE IFR CIGS TO BFD...JST AND AOO. WITH MVFR POSSIBLE
THE REST OF THE TAF SITES. THOUGH THE SYSTEM WILL BE DRIER AS IT
REACHES THE SOUTHEASTERN TAF SITES. THERE STILL REMAINS A CHANCE
FOR THUNDERSTORMS ACROSS SOUTHERN PA TUE AFTERNOON.
THE OTHER AVIATION CONCERN IS LOW LEVEL WIND SHEAR OUT AHEAD OF
THE LINE...AND HAVE PUT LLWS FOR AOO...JST...BFD AND UNV BETWEEN
09Z TO 14Z.
OUTLOOK...
WED...NO SIG WX EXPECTED.
THU-FRI...MVFR WITH SHRA LIKELY.
SAT...FAIR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DANGELO/DEVOIR
SHORT TERM...DEVOIR
LONG TERM...MARTIN
AVIATION...CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
751 PM EDT MON APR 25 2016
.SYNOPSIS...
LOW PRESSURE OVER THE UPPER MIDWEST MONDAY AFTERNOON WILL TRACK
THROUGH THE SOUTHERN GREAT LAKES TONIGHT AND ALONG THE
PENNSYLVANIA NEW YORK ON TUESDAY BEFORE PUSHING A COLD FRONT SOUTH
OF THE COMMONWEALTH BY WEDNESDAY MORNING. ANOTHER AREA OF LOW
PRESSURE TRACK SOUTH OF PENNSYLVANIA THURSDAY INTO FRIDAY.
&&
.NEAR TERM /UNTIL 7 AM TUESDAY MORNING/...
A FEW CLOUD FLASHES AND CGS INSIDE THE CONVECTION OVER CRAWFORD
CO...SO FEEL SAFE LEAVING MENTIONS OF THUNDER IN FOR THE NIGHT.
GOOD INFLOW FROM THE SW TO THESE SHOWERS - BUT THE DEWPOINTS ARE
ONLY 45-50F OVER SRN OH/SWRN PA. WITH THE QUICK MOTION AND LOW
MOISTURE - THESE SHOULD NOT EVEN MAKE HEAVY RAIN FOR MORE THAN A
MINUTE AT ANY LOCATION. HOWEVER...REPEATED CELLS PASSING OVERHEAD
COULD TAKE QPF INTO THE QUARTER TO HALF INCH ACROSS THE NRN TIER
BY MORNING. HRR AND RAP PROPAGATE THE FIRST BATCH OF PRECIP TO
THE EAST STEADILY. A SECOND AND PREHAPS THIRD WAVE OF
SHOWERS/TSTORMS IS FCST TO DEVELOP OVER NRN OH AND CROSS THE STATE
- MAINLY NORTH OF INTERSTATE 80 - LIKELY SKIRTING DRY/HAPPY
VALLEY.
PREV...
TRANSLUCENT MID LEVEL DECK INCREASING OVER CENTRAL PA EARLY THIS
AFTERNOON. MAIN BAROCLINIC ZONE AND OPAQUE CLOUDINESS RESIDE
NORTH OF THE PA/NY BORDER...AND MOST AREAS WILL REMAIN MOSTLY
SUNNY THROUGH THE THINK MID/HIGH CLOUD DECK. TEMPS QUITE WARM AND
RANGE FROM THE UPPER 60S THROUGH THE 70S ELSEWHERE.
HIGH LEVEL MOISTURE WILL CONTINUE TO INCREASE TONIGHT AHEAD OF AN
APPROACHING SHORTWAVE AND ASSOCIATED LOW PRESSURE TRACKING THROUGH
THE SOUTHERN GLAKS. POTENT SHORTWAVE AND ASSOC LL JET WILL BRING
A GOOD CHC OF SHOWERS AND ISOLD TSRA OVERNIGHT...PRIMARILY ACROSS
THE NORTHERN HALF OF THE STATE. STILL TIMING BEST CHANCE OF RAIN
BETWEEN 02Z TO 10Z TIMEFRAME. DIMINISHING CHC OF SHOWERS LINGERS
AFTERWARDS AS FRONT SAGS SOUTHWARD ACROSS THE COMMONWEALTH.
NORTHERN AND CENTRAL AREAS MAY SEE BETWEEN A QUARTER AND A THIRD
OF AN INCH OF RAIN...OUTLIERS NEAR ONE HALF...WHICH IS MUCH NEEDED
GIVEN RECENT DRYNESS.
&&
.SHORT TERM /7 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
SFC FRONTAL WAVE TRACKS ALONG THE PA/NY BORDER TUESDAY MORNING...
BEFORE SAGGING SOUTHWARD AS COLD FRONT SETTLES ACROSS THE
COMMONWEALTH. EXTREME SOUTHERN TIER REMAINS IN SPC MRGL OUTLOOK
WITH PERHAPS ENOUGH CAPE TO PRODUCE A STRONG STORM OR TWO BEFORE
THE FRONT SETTLES SOUTH OF THE MASON DIXON LINE TUE AFTERNOON.
MODELS SHOWING LOCAL PREFRONTAL 1000 J/KG CAPES IN THIS ALONG THE
MASON DIXON LINE TUE MORNING/AFTN.
COOL AIR REACHES THE NORTHWEST EARLY TUE...WITH HIGHS THERE ONLY
REACHING NEAR 60F. FARTHER SOUTH ANOTHER WARM DAY WILL BE SEEN
WITH HIGHS IN THE MID TO UPPER 70S FOR ONE MORE DAY ACROSS SOUTH
CENTRAL AND SOUTHEAST PA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
NOT A LOT OF CHANGE TO THIS PART OF THIS PACKAGE.
STILL LOOKS DRY ON WED...AS A NE FLOW OF DRY AIR BUILDS SOUTHWARD
FROM A LARGE HIGH OVER WESTERN HUDSON BAY.
A SYSTEM TRACKING SOUTH OF THE AREA ON THU WILL BRING SOME RAIN
AND COOL TEMPERATURES TO THE AREA.
A SECOND WEAK SYSTEM TRACKING SOUTH OF THE AREA OUT OF WV MAY
BRING SOME SHOWERS STILL ON FRIDAY. LEFT POPS IN.
STILL SOME HINTS OF A JET MAX DROPPING SE ON SAT...BUT REALLY
NO MOISTURE TO WORK WITH. THUS STILL EXPECT THE DAY TO BE DRY.
MID SHIFT HAD SOME SHOWERS IN FOR LATER ON SUNDAY. YESTERDAY THE
EC WAS TOO FAST...STILL THAT WAY TODAY. LEFT POPS IN BUT DID LOWER
SOME FOR SUNDAY AND SUNDAY NIGHT.
FOR SUNDAY NIGHT..DID EDGE TEMPERATURES DOWN A LITTLE.
LOOKS WET AND COOL FOR MONDAY. DID NOT GO QUITE AS HIGH AS
THE SUPERBLEND WITH THE POPS.
CLEARING OUT LATER MONDAY NIGHT.
OVERALL A PATTERN THAT FAVORS WETTER AND COOLER WEATHER
THAN WE HAVE HAD LATELY.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
HIGH PRESSURE CONTINUES TO EXIT OFFSHORE...WHILE A BOUNDARY SETS
UP ALONG THE NEW YORK BORDER. LOW PRESSURE WILL TRACK ALONG THE
BOUNDARY ON TUESDAY...PUSHING IT SOUTHWARD ACROSS THE STATE AS A
COLD FRONT. WIDESPREAD VFR CONDITIONS WILL CONTINUE INTO TONIGHT
UNDER INFLUENCE OF HIGH PRESSURE. WINDS WILL REMAIN VERY LIGHT.
AS A BOUNDARY STARTS TO SLIP SOUTHWARD INTO THE NORTHERN MTNS
TONIGHT...SHOWERS WILL BECOME LIKELY OVER THE NORTHERN HALF...WITH
RESTRICTIONS POSS NORTH OF I-80. THUNDERSTORMS WILL BE POSSIBLE
ACROSS SOUTHERN PA TUE AFT.
OUTLOOK...
TONIGHT-TUE...SHRA DEVELOPING THIS EVE AND CONTINUING INTO
TUESDAY. REDUCTIONS POSSIBLE...MAINLY NW PA.
WED...NO SIG WX EXPECTED.
THU-FRI...MVFR WITH SHRA LIKELY.
SAT...FAIR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DANGELO/DEVOIR
SHORT TERM...DEVOIR
LONG TERM...MARTIN
AVIATION...DEVOIR/MARTIN
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
636 PM CDT MON APR 25 2016
.AVIATION...
SOUTHWEST FLOW WILL STRENGTHEN NOTABLY IN THE COMING 24 HOURS AS A
DEEP UPPER LOW OVER THE EASTERN GREAT BASIN THIS EVENING MOVES TO THE
CENTRAL HIGH PLAINS LATE TUESDAY. ADDED A PERIOD AROUND MIDDAY FOR
KLBB AND KPVW FOR A SHARP INCREASE IN WIND SPEEDS AT THAT TIME
WITH MINOR VISIBILITY RESTRICTION AS WELL. WILL ADDRESS KCDS WIND
ISSUES FOR THE 06Z PACKAGE. TONIGHT WE EXPECT A WEAK UPPER IMPULSE
CURRENTLY CROSSING NORTHERN CHIHUAHUA MEXICO TO MOVE ACROSS OUR
SOUTHEAST ZONES EARLY TUESDAY. APPEARS RAP AND HRRR SOLUTIONS MAY
BE OVERDOING FORECAST THUNDERSTORMS LATE TONIGHT SINCE WE ARE
SEEING LITTLE TO NOTHING DEVELOPING TO OUR SOUTHWEST AT THIS TIME.
BUT WILL KEEP A CLOSE EYE AS THE EVENING PROGRESSES. ALSO WATCHING
FOR DRY-LINE RETREAT INTO THE ROLLING PLAINS TONIGHT BEFORE LOW
LEVEL FLOW VEERS LATER TUESDAY MORNING. OUTSIDE CHANCE STILL OF
STRATUS AS FAR WEST AS KCDS SO WILL RETAIN THE PREVIOUS MENTION OF
FEW020 AT KCDS. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 336 PM CDT MON APR 25 2016/
SHORT TERM...
THE DRYLINE HAS MOVED EAST OF THE FORECAST AREA MONDAY AFTERNOON
WITH TEMPERATURES IN THE MID TO UPPER 80S...AND A FEW LOWER
90S...BEING REPORTED AREA-WIDE AT 3 PM. OFF TO OUR WEST...WATER
VAPOR IMAGERY SHOWS A LARGE TROUGH ACROSS THE DESERT SOUTHWEST.
LOWER AND MID-LEVEL FLOW IS FORECAST TO ONLY BACK SLIGHTLY TONIGHT
AS THE TROUGH APPROACHES BUT THIS WILL LIKELY BE ENOUGH TO DRAW THE
DRYLINE BACK WEST INTO THE SOUTHERN AND EASTERN ROLLING PLAINS. SOME
LOW STRATUS WILL BE POSSIBLE IN THAT AREA EARLY TUESDAY
MORNING...BUT CONFIDENCE IS LOW.
THE DRYLINE WILL RACE EAST ON TUESDAY AS A STRONG UPPER-LEVEL JET
EMERGES OVER WEST TEXAS. A DRY AND DEEPLY MIXED AIRMASS WILL SPREAD
ACROSS OUR FORECAST AREA WITH GUSTY SOUTHWEST TO WEST WINDS
DEVELOPING IN THE AFTERNOON. WE ARE STILL EXPECTING BREEZY TO WINDY
CONDITIONS ON THE CAPROCK WITH SPEEDS GENERALLY IN THE 25 TO 35 MPH
RANGE...WITH GUSTS WELL INTO THE 40S...AND PERHAPS SLIGHTLY HIGHER
ROUGHLY TO THE WEST OF INTERSTATE 27/HIGHWAY 87. SOME PATCHY BLOWING
DUST APPEARS LIKELY AS MAY FIELDS ACROSS THE AREA ARE BEING PLOWED
FOR SPRING PLANTING. COLD ADVECTION WILL SPREAD IN FROM THE WEST BY
AFTERNOON AND TEMPS ARE LIKELY TO BE COOLER ON THE CAPROCK...WITH
HIGHS IN THE 70S TO LOW 80S...AND MID TO UPPER 80S IN THE ROLLING
PLAINS.
LONG TERM...
TUE NIGHT/WED...UPPER LOW WILL CONTINUE LIFTING INTO CENTRAL PLAINS
LATE TUE INTO WED. DRY AIR WILL CONT IN PLACE WITH SURFACE GRADIENT
WEAKENING DURING THE AFTERNOON RESULTING IN MODERATE WLY WINDS
DECREASING AFTER 21Z. DRYLINE WILL REMAIN WELL EAST OF THE REGION IN
WRN OK AND NW TEXAS. MINIMAL FORCING AS WEAK DOWNSTREAM RIDGING AND
WARMING MID LEVEL TEMPS KEEP SFC TEMPS WARM AND CLOUD COVER TO
MINIMUM.
WED NIGHT/THURSDAY...A RETREATING DRY LINE AND INCREASING FLOW ALOFT
WILL MATERIALIZE AS UPPER LOW TRANSLATES EWD TO CENTRAL AZ WITH
ENERGETIC UPR TROUGH APPROACHING W TX. WEAK FRONT LOOKS TO PUSH
SOUTHWARD INTO PANHANDLE TOWARD 12Z THUR. TOO EARLY TO DETERMINE
WHERE THIS BOUNDARY WILL SET UP AFTER A POSSIBLE NORTHWARD RETREAT
IN THE AFTERNOON. BACKING LOW LEVEL FLOW WILL TRANSPORT SOME GULF
MOISTURE AT LEAST INTO ROLLING PLAINS AND PERHAPS FARTHER WEST.
SEVERE STORMS CERTAINLY LOOK POSSIBLE ESPECIALLY NEAR TRIPLE
POINT...BUT THAT COULD BE FARTHER NORTH OR NE OF FA...AND ATMOSPHERE
MAY BE SOMEWHAT CAPPED FARTHER SOUTH WITH MORE LIMITED COVERAGE.
CERTAINLY RISK OF SEVERE THURSDAY.
BY LATE THURSDAY...IF TIMING OF GFS/ECM IS TO BE BELIEVED...LOW
CLOUDS/HIGHER DEWPOINTS LIKELY TO RETURN WWD INTO EARLY FRIDAY WITH
HIGHER COVERAGE OF SHOWERS/SOME THUNDER POSSIBLE OVERNIGHT WITH
MODERATE FORCING ALOFT. DRYLINE EXPECTED TO RAPIDLY SURGE EAST AS
STRONGEST UPPER LEVEL WINDS WITH TROF MOVE ACROSS AREA FRIDAY
AFTERNOON. COULD SEE SOME ACTIVITY EARLY...BUT DRYLINE MAY BE EAST
OF THE REGION BY LATE AFTERNOON FRI. EXTREME ERN COUNTIES MOST
LIKELY TO HAVE A CONDITIONAL SEVERE CHANCE THEN.
WEEKEND INTO EARLY NEXT WEEK...ELONGATED UPPER TROUGH WILL STRETCH
ACROSS THE WESTERN CONUS SATURDAY WITH WESTERLY FLOW ALOFT ACROSS
THE AREA WITH DRY WEATHER ANTICIPATED AT THIS TIME. ANOTHER FRONT
COULD ENTER THE PICTURE LATE SATURDAY OR ON SUNDAY...WITH MODELS NOT
OVERLY EXCITED ABOUT RAIN COVERAGE. NEXT LOW ATTM WILL DIG INTO
SRN AZ WITH BRIEF DOWNSTREAM RIDGING LIKELY LATE SUNDAY. BY SUNDAY
NIGHT...UPPER HEIGHT FIELD WOULD SUGGEST MODERATE/STRONG FORCING
IN EASTERN NEW MEXICO WITH DIFLUENT NEG TILTED UPR TROF
APPROACHING WITHIN LARGE SCALE REX BLOCK/SPLIT FLOW PATTERN ACROSS
WRN/CNTRL US. COOL NE SURFACE FLOW CONTG WITH CLOUDY...COOL
WEATHER. PRECIPITATION COULD BECOME WIDESPREAD EARLY NEXT WEEK IN
POST FRONTAL ENVIRONMENT WITH SW FLOW ALOFT ABOVE SFC HIGH
PRESSURE RIDGE...KEEPING CHANCE OF RAIN IN FCST ALONG WITH
POTENTIALLY MUCH COOLER TEMPS.
FIRE WEATHER...
DESPITE THE COOLER TEMPS...NEAR SEASONAL NORMS FOR LATE APRIL...A
VERY DRY AIRMASS WILL RESULT IN RH VALUES FALLING INTO THE SINGLE
DIGITS ACROSS THE WESTERN SOUTH PLAINS AND FAR SOUTHWEST TEXAS
PANHANDLE TUESDAY AFTERNOON. COMBINED WITH GUSTY S-SW WINDS...THIS
WILL RESULT IN A PERIOD OF METEOROLOGICAL CRITICAL CONDITIONS.
HOWEVER...THE RECENT GREEN-UP OF GRASSES...REFLECTED IN LOW ERC
VALUES...MEANS THAT FUELS ARE NOT PARTICULARLY RESPONSIVE TO FIRE
STARTS. ERC VALUES HAVE TRENDED HIGHER THOUGH DUE TO THE RECENT DRY
WEATHER. WE WILL HOLD OFF ON ANY FIRE DANGER HIGHLIGHTS AT THIS TIME
GIVEN THE STATE OF THE FUELS...BUT A FIRE DANGER STATEMENT MAY BE
ISSUED FOR THE SITUATION TUESDAY.
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/05
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
104 PM CDT SUN APR 24 2016
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...A MULTI-LEVEL CLOUD DECK PREVAILS ACROSS DEEP SOUTH
TEXAS THIS AFTERNOON WITH A MIX OF VFR/MVFR CEILINGS. WILL MENTION
TEMPO MVFR CEILINGS THROUGH AROUND 21Z BEFORE SOME LOW LEVEL
MIXING OCCURS. A MID LEVEL DISTURBANCE OVERHEAD WILL CONTINUE TO
MOVE EAST THIS AFTERNOON AND TODAY. NO WIDESPREAD CONVECTION IS
EXPECTED THROUGH THE NEXT 24 HOURS AS THE ATMOSPHERE HAS STABILIZED
ACROSS MUCH OF DEEP SOUTH TEXAS. HOWEVER...WILL INCLUDE VCSH AT
VALLEY TAF SITES THROUGH MID AFTERNOON FOR AN ISOLATED -SHRA OR
TWO. VFR TAFS OTHERWISE UNTIL LATE TONIGHT THEN MVFR CEILINGS
EXPECTED TO RETURN TO THE AREA. LIGHT TO MODERATE SOUTHEAST TO
SOUTH WINDS TODAY AND TONIGHT. VFR CONDITIONS DEVELOP ALONG WITH
BREEZY SOUTHEAST TO SOUTH WINDS AROUND MID-MORNING MONDAY.
&&
.PREV DISCUSSION... /ISSUED 916 AM CDT SUN APR 24 2016/
DISCUSSION...BROWNSVILLE RADAR SHOWS THE LARGE AREA OF
SHOWERS AND THUNDERSTORMS MOVING EAST OF THE LOWER TEXAS GULF
WATERS THIS MORNING. THE ATMOSPHERE HAS STABILIZED ACROSS MUCH OF
DEEP SOUTH TEXAS THIS MORNING IN THE WAKE OF THE OVERNIGHT
CONVECTION. THE COMBINATION OF THE APPROACHING UPPER LEVEL
DISTURBANCE...DAYTIME HEATING AND THE MOIST AIR MASS IN PLACE
WILL SUPPORT THE DEVELOPMENT OF CONVECTION THIS AFTERNOON. THE
STORM PREDICTION CENTER /SPC/ CONTINUES TO HAVE MOST OF DEEP SOUTH
TEXAS UNDER A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR TODAY.
MADE A QUICK UPDATE TO LOWER POPS FOR THIS MORNING AND MADE SOME
MINOR ADJUSTMENTS TO THE POP AND QPF GRIDS. NO OTHER CHANGES
NEEDED.
PREV DISCUSSION... /ISSUED 639 AM CDT SUN APR 24 2016/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...CEILINGS HAVE TEMPORARILY LIFTED...BUT THE MID LEVEL
DISTURBANCE MOVING OVER CENTRAL TEXAS MAY HAVE A BIT OF ENERGY
LEFT IN IT...WITH MVFR CEILINGS BUILT INTO THE TAFS FOR A FEW
HOURS FROM MID MORNING TO MID AFTERNOON...WITH ANY REMAINING
RESIDUAL RAIN CHANCES. VFR TAFS OTHERWISE UNTIL LATE TONIGHT.
WINDS WILL REMAIN LIGHT TO MODERATE SOUTHEAST.
PREV DISCUSSION... /ISSUED 428 AM CDT SUN APR 24 2016/
SHORT TERM /NOW THROUGH MONDAY/...A MID LEVEL SHORT WAVE TROUGH
WILL TRUNDLE ACROSS SOUTH CENTRAL TEXAS TODAY AND...WITH DAYTIME
HEATING...HAS PROMPTED A MARGINAL RISK OF SVR WEATHER CATEGORIZATION
FROM SPC. THE MAIN THREAT TODAY...AS SCATTERED THUNDERSTORMS DEVELOP
AND MOVE ACROSS THE AREA...WILL BE STRONG WIND GUSTS...FREQUENT
LIGHTNING...SMALL HAIL AND BRIEF HEAVY DOWNPOURS.
A ROUND OF SHOWERS AND THUNDERSTORMS HAS ALREADY MOVED THROUGH THE
AREA THIS MORNING...CONFIRMING THE THREAT FOR LIGHTNING...BRIEF
DOWNPOURS AND GUSTY WINDS...BUT RADAR ALSO SHOWS MORE DEVELOPMENT
TO THE SOUTH...AND THERE IS NO REASON TO BELIEVE THAT SOME
CONVECTION WILL NOT KEEP COMING THROUGH THE DAY. THE HRRR AND NAM
SHOW SOME QPF OVER EASTERN SECTIONS.
CONVECTION SHOULD END THIS EVENING...EXCEPT POSSIBLY FOR THE MARINE
AREAS...WITH IMPROVING CONDITIONS. LOOK FOR MODERATE SOUTHEAST WINDS
AND A MIX OF CLOUDS AND SUN ON MONDAY. HIGH TEMPS WILL RANGE FROM
THE 80S AT THE COAST TO THE UPPER 90S FAR WEST.
LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...THE ONLY OPPORTUNITY
FOR PRECIPITATION DURING THE LONG TERM PORTION OF THE FORECAST
WILL OCCUR ON WEDNESDAY...AS THE INTRUSION OF A WEAK COLD FRONT
INTO DEEP SOUTH TEXAS AND THE RIO GRANDE VALLEY COMBINES WITH
DECENT AVAILABLE MOISTURE AND DAYTIME HEATING TO PRODUCE ISOLATED
SHOWERS AND THUNDERSTORMS. THE REMAINDER OF THE FORECAST WILL BE
DRY WITH NO OTHER COLD FRONT PASSAGES OR SIGNIFICANT DISTURBANCES
AT THE 500 MB LEVEL. MAINLY PARTLY CLOUDY SKIES WILL SUPPORT WELL
ABOVE NORMAL DAYTIME HIGH AND OVERNIGHT LOW TEMPERATURES.
MARINE...NOW THROUGH MONDAY...LIGHT SOUTHEAST WINDS WILL INCREASE
TO HIGH END MODERATE THIS AFTERNOON AS HIGH PRESSURE OVER THE
NORTHWEST GULF INTERACTS WITH LOWER PRESSURE OVER THE HIGH PLAINS.
MODERATE WINDS WILL CONTINUE TONIGHT AND SEAS WILL BUILD...WITH
POSSIBLE SMALL CRAFT SHOULD EXERCISE CAUTION CONDITIONS. HIGH END
MODERATE WINDS WILL REPEAT ON MONDAY. SHOWERS AND THUNDERSTORMS
WILL BE POSSIBLE TODAY AS AN UPPER DISTURBANCE INFLUENCES THE
AREA.
MONDAY NIGHT THROUGH SATURDAY...SMALL CRAFT EXERCISE CAUTION
AND SMALL CRAFT ADVISORY WILL DOMINATE THROUGHOUT THE LONG
TERM PORTION OF THE MARINE FORECAST...WITH HIGH PRESSURE OVER
THE GULF OF MEXICO INTERACTING WITH LOWER PRESSURE INLAND.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
63
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
916 AM CDT SUN APR 24 2016
.DISCUSSION...BROWNSVILLE RADAR SHOWS THE LARGE AREA OF
SHOWERS AND THUNDERSTORMS MOVING EAST OF THE LOWER TEXAS GULF
WATERS THIS MORNING. THE ATMOSPHERE HAS STABILIZED ACROSS MUCH OF
DEEP SOUTH TEXAS THIS MORNING IN THE WAKE OF THE OVERNIGHT
CONVECTION. THE COMBINATION OF THE APPROACHING UPPER LEVEL
DISTURBANCE...DAYTIME HEATING AND THE MOIST AIR MASS IN PLACE
WILL SUPPORT THE DEVELOPMENT OF CONVECTION THIS AFTERNOON. THE
STORM PREDICTION CENTER /SPC/ CONTINUES TO HAVE MOST OF DEEP SOUTH
TEXAS UNDER A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR TODAY.
MADE A QUICK UPDATE TO LOWER POPS FOR THIS MORNING AND MADE SOME
MINOR ADJUSTMENTS TO THE POP AND QPF GRIDS. NO OTHER CHANGES
NEEDED.
&&
.PREV DISCUSSION... /ISSUED 639 AM CDT SUN APR 24 2016/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...CEILINGS HAVE TEMPORARILY LIFTED...BUT THE MID LEVEL
DISTURBANCE MOVING OVER CENTRAL TEXAS MAY HAVE A BIT OF ENERGY
LEFT IN IT...WITH MVFR CEILINGS BUILT INTO THE TAFS FOR A FEW
HOURS FROM MID MORNING TO MID AFTERNOON...WITH ANY REMAINING
RESIDUAL RAIN CHANCES. VFR TAFS OTHERWISE UNTIL LATE TONIGHT.
WINDS WILL REMAIN LIGHT TO MODERATE SOUTHEAST.
PREV DISCUSSION... /ISSUED 428 AM CDT SUN APR 24 2016/
SHORT TERM /NOW THROUGH MONDAY/...A MID LEVEL SHORT WAVE TROUGH
WILL TRUNDLE ACROSS SOUTH CENTRAL TEXAS TODAY AND...WITH DAYTIME
HEATING...HAS PROMPTED A MARGINAL RISK OF SVR WEATHER CATEGORIZATION
FROM SPC. THE MAIN THREAT TODAY...AS SCATTERED THUNDERSTORMS DEVELOP
AND MOVE ACROSS THE AREA...WILL BE STRONG WIND GUSTS...FREQUENT
LIGHTNING...SMALL HAIL AND BRIEF HEAVY DOWNPOURS.
A ROUND OF SHOWERS AND THUNDERSTORMS HAS ALREADY MOVED THROUGH THE
AREA THIS MORNING...CONFIRMING THE THREAT FOR LIGHTNING...BRIEF
DOWNPOURS AND GUSTY WINDS...BUT RADAR ALSO SHOWS MORE DEVELOPMENT
TO THE SOUTH...AND THERE IS NO REASON TO BELIEVE THAT SOME
CONVECTION WILL NOT KEEP COMING THROUGH THE DAY. THE HRRR AND NAM
SHOW SOME QPF OVER EASTERN SECTIONS.
CONVECTION SHOULD END THIS EVENING...EXCEPT POSSIBLY FOR THE MARINE
AREAS...WITH IMPROVING CONDITIONS. LOOK FOR MODERATE SOUTHEAST WINDS
AND A MIX OF CLOUDS AND SUN ON MONDAY. HIGH TEMPS WILL RANGE FROM
THE 80S AT THE COAST TO THE UPPER 90S FAR WEST.
LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...THE ONLY OPPORTUNITY
FOR PRECIPITATION DURING THE LONG TERM PORTION OF THE FORECAST
WILL OCCUR ON WEDNESDAY...AS THE INTRUSION OF A WEAK COLD FRONT
INTO DEEP SOUTH TEXAS AND THE RIO GRANDE VALLEY COMBINES WITH
DECENT AVAILABLE MOISTURE AND DAYTIME HEATING TO PRODUCE ISOLATED
SHOWERS AND THUNDERSTORMS. THE REMAINDER OF THE FORECAST WILL BE
DRY WITH NO OTHER COLD FRONT PASSAGES OR SIGNIFICANT DISTURBANCES
AT THE 500 MB LEVEL. MAINLY PARTLY CLOUDY SKIES WILL SUPPORT WELL
ABOVE NORMAL DAYTIME HIGH AND OVERNIGHT LOW TEMPERATURES.
MARINE...NOW THROUGH MONDAY...LIGHT SOUTHEAST WINDS WILL INCREASE
TO HIGH END MODERATE THIS AFTERNOON AS HIGH PRESSURE OVER THE
NORTHWEST GULF INTERACTS WITH LOWER PRESSURE OVER THE HIGH PLAINS.
MODERATE WINDS WILL CONTINUE TONIGHT AND SEAS WILL BUILD...WITH
POSSIBLE SMALL CRAFT SHOULD EXERCISE CAUTION CONDITIONS. HIGH END
MODERATE WINDS WILL REPEAT ON MONDAY. SHOWERS AND THUNDERSTORMS
WILL BE POSSIBLE TODAY AS AN UPPER DISTURBANCE INFLUENCES THE
AREA.
MONDAY NIGHT THROUGH SATURDAY...SMALL CRAFT EXERCISE CAUTION
AND SMALL CRAFT ADVISORY WILL DOMINATE THROUGHOUT THE LONG
TERM PORTION OF THE MARINE FORECAST...WITH HIGH PRESSURE OVER
THE GULF OF MEXICO INTERACTING WITH LOWER PRESSURE INLAND.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
63
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
639 AM CDT SUN APR 24 2016
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...CEILINGS HAVE TEMPORARILY LIFTED...BUT THE MID LEVEL
DISTURBANCE MOVING OVER CENTRAL TEXAS MAY HAVE A BIT OF ENERGY
LEFT IN IT...WITH MVFR CEILINGS BUILT INTO THE TAFS FOR A FEW
HOURS FROM MID MORNING TO MID AFTERNOON...WITH ANY REMAINING
RESIDUAL RAIN CHANCES. VFR TAFS OTHERWISE UNTIL LATE TONIGHT.
WINDS WILL REMAIN LIGHT TO MODERATE SOUTHEAST.
&&
.PREV DISCUSSION... /ISSUED 428 AM CDT SUN APR 24 2016/
SHORT TERM /NOW THROUGH MONDAY/...A MID LEVEL SHORT WAVE TROUGH
WILL TRUNDLE ACROSS SOUTH CENTRAL TEXAS TODAY AND...WITH DAYTIME
HEATING...HAS PROMPTED A MARGINAL RISK OF SVR WEATHER CATEGORIZATION
FROM SPC. THE MAIN THREAT TODAY...AS SCATTERED THUNDERSTORMS DEVELOP
AND MOVE ACROSS THE AREA...WILL BE STRONG WIND GUSTS...FREQUENT
LIGHTNING...SMALL HAIL AND BRIEF HEAVY DOWNPOURS.
A ROUND OF SHOWERS AND THUNDERSTORMS HAS ALREADY MOVED THROUGH THE
AREA THIS MORNING...CONFIRMING THE THREAT FOR LIGHTNING...BRIEF
DOWNPOURS AND GUSTY WINDS...BUT RADAR ALSO SHOWS MORE DEVELOPMENT TO
THE SOUTH...AND THERE IS NO REASON TO BELIEVE THAT SOME CONVECTION
WILL NOT KEEP COMING THROUGH THE DAY. THE HRRR AND NAM SHOW SOME QPF
OVER EASTERN SECTIONS.
CONVECTION SHOULD END THIS EVENING...EXCEPT POSSIBLY FOR THE MARINE
AREAS...WITH IMPROVING CONDITIONS. LOOK FOR MODERATE SOUTHEAST WINDS
AND A MIX OF CLOUDS AND SUN ON MONDAY. HIGH TEMPS WILL RANGE FROM
THE 80S AT THE COAST TO THE UPPER 90S FAR WEST.
LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...THE ONLY OPPORTUNITY
FOR PRECIPITATION DURING THE LONG TERM PORTION OF THE FORECAST
WILL OCCUR ON WEDNESDAY...AS THE INTRUSION OF A WEAK COLD FRONT
INTO DEEP SOUTH TEXAS AND THE RIO GRANDE VALLEY COMBINES WITH
DECENT AVAILABLE MOISTURE AND DAYTIME HEATING TO PRODUCE ISOLATED
SHOWERS AND THUNDERSTORMS. THE REMAINDER OF THE FORECAST WILL BE
DRY WITH NO OTHER COLD FRONT PASSAGES OR SIGNIFICANT DISTURBANCES
AT THE 500 MB LEVEL. MAINLY PARTLY CLOUDY SKIES WILL SUPPORT WELL
ABOVE NORMAL DAYTIME HIGH AND OVERNIGHT LOW TEMPERATURES.
MARINE...NOW THROUGH MONDAY...LIGHT SOUTHEAST WINDS WILL INCREASE
TO HIGH END MODERATE THIS AFTERNOON AS HIGH PRESSURE OVER THE
NORTHWEST GULF INTERACTS WITH LOWER PRESSURE OVER THE HIGH PLAINS.
MODERATE WINDS WILL CONTINUE TONIGHT AND SEAS WILL BUILD...WITH
POSSIBLE SMALL CRAFT SHOULD EXERCISE CAUTION CONDITIONS. HIGH END
MODERATE WINDS WILL REPEAT ON MONDAY. SHOWERS AND THUNDERSTORMS
WILL BE POSSIBLE TODAY AS AN UPPER DISTURBANCE INFLUENCES THE
AREA.
MONDAY NIGHT THROUGH SATURDAY...SMALL CRAFT EXERCISE CAUTION
AND SMALL CRAFT ADVISORY WILL DOMINATE THROUGHOUT THE LONG
TERM PORTION OF THE MARINE FORECAST...WITH HIGH PRESSURE OVER
THE GULF OF MEXICO INTERACTING WITH LOWER PRESSURE INLAND.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
54/66/65
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
428 AM CDT SUN APR 24 2016
.SHORT TERM /NOW THROUGH MONDAY/...A MID LEVEL SHORT WAVE TROUGH
WILL TRUNDLE ACROSS SOUTH CENTRAL TEXAS TODAY AND...WITH DAYTIME
HEATING...HAS PROMPTED A MARGINAL RISK OF SVR WEATHER CATEGORIZATION
FROM SPC. THE MAIN THREAT TODAY...AS SCATTERED THUNDERSTORMS DEVELOP
AND MOVE ACROSS THE AREA...WILL BE STRONG WIND GUSTS...FREQUENT
LIGHTNING...SMALL HAIL AND BRIEF HEAVY DOWNPOURS.
A ROUND OF SHOWERS AND THUNDERSTORMS HAS ALREADY MOVED THROUGH THE
AREA THIS MORNING...CONFIRMING THE THREAT FOR LIGHTNING...BRIEF
DOWNPOURS AND GUSTY WINDS...BUT RADAR ALSO SHOWS MORE DEVELOPMENT TO
THE SOUTH...AND THERE IS NO REASON TO BELIEVE THAT SOME CONVECTION
WILL NOT KEEP COMING THROUGH THE DAY. THE HRRR AND NAM SHOW SOME QPF
OVER EASTERN SECTIONS.
CONVECTION SHOULD END THIS EVENING...EXCEPT POSSIBLY FOR THE MARINE
AREAS...WITH IMPROVING CONDITIONS. LOOK FOR MODERATE SOUTHEAST WINDS
AND A MIX OF CLOUDS AND SUN ON MONDAY. HIGH TEMPS WILL RANGE FROM
THE 80S AT THE COAST TO THE UPPER 90S FAR WEST.
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...THE ONLY OPPORTUNITY
FOR PRECIPITATION DURING THE LONG TERM PORTION OF THE FORECAST
WILL OCCUR ON WEDNESDAY...AS THE INTRUSION OF A WEAK COLD FRONT
INTO DEEP SOUTH TEXAS AND THE RIO GRANDE VALLEY COMBINES WITH
DECENT AVAILABLE MOISTURE AND DAYTIME HEATING TO PRODUCE ISOLATED
SHOWERS AND THUNDERSTORMS. THE REMAINDER OF THE FORECAST WILL BE
DRY WITH NO OTHER COLD FRONT PASSAGES OR SIGNIFICANT DISTURBANCES
AT THE 500 MB LEVEL. MAINLY PARTLY CLOUDY SKIES WILL SUPPORT WELL
ABOVE NORMAL DAYTIME HIGH AND OVERNIGHT LOW TEMPERATURES.
&&
.MARINE...NOW THROUGH MONDAY...LIGHT SOUTHEAST WINDS WILL INCREASE
TO HIGH END MODERATE THIS AFTERNOON AS HIGH PRESSURE OVER THE
NORTHWEST GULF INTERACTS WITH LOWER PRESSURE OVER THE HIGH PLAINS.
MODERATE WINDS WILL CONTINUE TONIGHT AND SEAS WILL BUILD...WITH
POSSIBLE SMALL CRAFT SHOULD EXERCISE CAUTION CONDITIONS. HIGH END
MODERATE WINDS WILL REPEAT ON MONDAY. SHOWERS AND THUNDERSTORMS
WILL BE POSSIBLE TODAY AS AN UPPER DISTURBANCE INFLUENCES THE
AREA.
MONDAY NIGHT THROUGH SATURDAY...SMALL CRAFT EXERCISE CAUTION
AND SMALL CRAFT ADVISORY WILL DOMINATE THROUGHOUT THE LONG
TERM PORTION OF THE MARINE FORECAST...WITH HIGH PRESSURE OVER
THE GULF OF MEXICO INTERACTING WITH LOWER PRESSURE INLAND.
&&
.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL 82 74 86 74 / 60 20 10 0
BROWNSVILLE 84 74 87 74 / 70 20 0 0
HARLINGEN 85 73 91 74 / 60 20 0 0
MCALLEN 89 73 94 74 / 30 10 0 0
RIO GRANDE CITY 91 72 98 73 / 40 20 0 0
SOUTH PADRE ISLAND 79 74 82 73 / 70 20 10 0
&&
.BRO WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
SHORT TERM...MILLER-54
LONG TERM...TOMASELLI-66
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1145 PM CDT SAT APR 23 2016
.AVIATION...
VFR CONDS EXPECTED THROUGH ABOUT 09Z. MIGHT GET SOME SHALLOW
GROUND FOG ONCE AGAIN BUT CIRRUS STREAMING INTO THE AREA WILL
LIMIT COVERAGE AND INTENSITY. WATER VAPOR CONTS TO SHOW A WELL
DEFINED S/WV OVER NORTHERN MEXICO HEADING TOWARD SE TX AND FEEL
THIS DISTURBANCE WILL TRIGGER SHRA/TSRA BY 18Z WITH SHRAS
BEGINNING AS EARLY AS 15-16Z. FCST SOUNDINGS SHOWING BETTER
POTENTIAL FOR PRECIP COVERAGE WITH THE NAM/GFS/ECMWF ALL LOOKING
SIMILAR. PW VALUES INCREASE TO 1.73 INCHES WITH CAPE AROUND 1000.
43
&&
.PREV DISCUSSION... /ISSUED 1010 PM CDT SAT APR 23 2016/
UPDATE...
CONVECTION CONTINUES TO DEVELOP ALONG THE LOWER RIO GRANDE THIS
EVENING ASSOCIATED WITH A COMPACT SHORTWAVE PUSHING EAST INTO THE
STATE. EXPECT HIGH CLOUDS ASSOCIATED WITH THIS ACTIVITY TO
OVERSPREAD THE REGION FROM THE WEST/SOUTHWEST TONIGHT. THINK MOST
OF THE REGION WILL STAY DRY TONIGHT... BUT ADDED CHANCE/30 POPS
OVER THE SOUTHWESTERN COUNTIES/MATAGORDA BAY AREA SUNDAY MORNING
WITH THE APPROACH OF THE SHORTWAVE AND LOW LEVEL MOISTURE RETURN
OCCURRING MUCH QUICKER THAN WHAT PRELIMINARY 00Z GUIDANCE AND THE
LATEST RAP ARE SUGGESTING. THE KHGX VAD WIND PROFILE ALREADY SHOWS
SOUTHERLY FLOW 15-20 KNOTS THROUGH 5KFT... WITH THE GUIDANCE
INSISTING ON A MORE BACKED/DRIER FLOW PERSISTING UNTIL AFTER 06Z.
OTHERWISE... EXPECT OVERNIGHT LOWS TO FALL INTO THE UPPER 50S TO
MID 60S.
HUFFMAN
PREV DISCUSSION... /ISSUED 318 PM CDT SAT APR 23 2016/
DISCUSSION...
GIVEN THE WAY THIS WEEK STARTED...GREAT TO END THE WEEK WITH SOME
BEAUTIFUL WEATHER ACROSS SE TEXAS. TEMPERATURES HAVE REACHED THE
LOW 80S WITH LOW HUMIDITY THIS AFTERNOON. ONE CANNOT ASK FOR MUCH
BETTER WEATHER TO BE OUTSIDE.
SUNDAY AN UPPER LEVEL TROUGH SHOULD MOVE OVER THE REGION DURING
THE AFTERNOON AND EVENING. WATER VAPOR SATELLITE IMAGERY SHOWS
THIS SYSTEM OVER MEXICO. THE FORECAST WILL KEEP SOME HIGHER RAIN
CHANCES OFF TO THE SOUTHWEST OF HOUSTON BUT LOOKS LIKE THOSE
CHANCES DIMINISH TOWARDS THE EVENING HOURS. OUTSIDE OF THE
CANADIAN MODEL...MOST MODELS INCLUDING HIGH RESOLUTION CONVECTIVE
ALLOWING MODELS DO NOT PRODUCE MUCH CONVECTION. GFS SEEMS TO BE ON
THE HIGH END FOR QPF BUT EVEN IT ENDS PRECIPITATION IN THE
EVENING. REGARDLESS CLOUD COVER SHOULD INCREASE ACROSS THE AREA
AND HOLD TEMPERATURES IN THE LOW 80S AS MOISTURE RETURNS.
WATER VAPOR IMAGERY SHOWS ANOTHER STRONG UPPER LOW AND JET STREAM
OUT OVER THE PACIFIC AND GULF OF ALASKA. THIS SYSTEM SHOULD PULL
INTO THE ROCKIES TUESDAY MORNING AND INTO THE PLAINS BY 00Z
WEDNESDAY. THIS SYSTEM WILL PROVIDE A FAVORABLE SET UP FOR SEVERE
WEATHER ACROSS THE PLAINS. ACROSS SOUTHEAST TEXAS...FAIRLY STRONG
CAP IS EXPECTED TO DEVELOP WHICH SHOULD RESTRICT CONVECTIVE
DEVELOPMENT. THERE STILL MAY BE SOME PASSING SHOWERS DUE TO
MOISTURE/WARM AIR ADVECTION PATTERN. A TRAILING PACIFIC FRONT OR
DRY LINE MAY PUSH INTO THE AREA AND STALL ON WEDNESDAY SO
MAINTAINED 30/40 POPS FOR THE REGION. THE GFS AND ECMWF HAVE SOME
DIFFERENCES IN THIS EVOLUTION WITH THE ECMWF MORE AGGRESSIVE WITH
PRECIP CHANCES. THAT SAID...GFS MODEL SOUNDINGS SHOW THE CAP
WEAKENING ON WEDNESDAY.
IN THE EXTENDED FORECAST...WE WILL NEED TO KEEP AN EYE ON THE NEXT
SYSTEM AFTER THE MIDWEEK SYSTEM. BOTH GFS/ECMWF DEPICT A DEEP
TROUGH OVER THE SOUTHERN ROCKIES. ECMWF IS MORE CONCERNING SINCE
IT HAS A BETTER DIFFLUENT JET STRUCTURE WHICH WOULD ALLOW FOR A
WEAKER CAP AND WIDESPREAD CONVECTION. THIS IS A MODEL SIGNAL THAT
MAY NEED TO BE MONITORED IN THE MODEL RUNS FOR THE NEXT FEW DAYS.
THE ECMWF SOLUTION WILL LARGELY DEPEND ON HOW DEEP THE TROUGH
DEVELOPS OVER THE SOUTHERN ROCKIES INTO MEXICO.
OVERPECK
MARINE...
LIGHT OFFSHORE WINDS WILL PREVAIL OVER THE COASTAL WATERS TONIGHT.
OVER THE BAYS THE BRIEF ONSHORE FLOW IN THE WAKE OF THE SEABREEZE
SHOULD GIVE WAY TO A LIGHT ELY FLOW OVERNIGHT. WITH THE SFC HIGH
MOVING FURTHER EAST OF THE REGION TOMORROW...ONSHORE WINDS ARE EX-
PECTED TO RETURN ACROSS THE AREA TOMORROW...STRENGTHENING THROUGH
MUCH OF THE UPCOMING WEEK IN RESPONSE TO A SERIES OF DISTURBANCES
MOVING IN FROM THE SW. WE COULD SEE CAUTION FLAGS OVER THE MARINE
WATERS STARTING MON NIGHT ON INTO THURS. 41
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 60 81 67 84 69 / 10 20 20 10 10
HOUSTON (IAH) 61 81 67 83 70 / 10 20 20 10 10
GALVESTON (GLS) 68 77 71 79 73 / 10 30 20 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...14
AVIATION/MARINE...43
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1130 PM CDT SAT APR 23 2016
.AVIATION...
BREEZY SOUTH WINDS TO VEER TO SW AS AN UPPER LEVEL SHORT WAVE
TROUGH MOVES ACROSS THE HIGH PLAINS. THERE IS AN OUTSIDE CHANCE
FOR STRATUS TO DEVELOP VCNTY KLBB AND KPVW AROUND 12Z SUNDAY.
CHANCE IS VERY LOW AND WILL TAFS VFR THROUGH THE PERIOD.
&&
.PREV DISCUSSION... /ISSUED 627 PM CDT SAT APR 23 2016/
AVIATION...
AN UPPER LEVEL SHORT WAVE TROUGH WILL EJECT FROM THE COLORADO
ROCKIES ONTO THE CENTRAL HIGH PLAINS SUNDAY MORNING. SFC PRESSURE
GRADIENT WILL REMAIN TIGHT...KEEPING SOUTH WINDS BREEZY OVERNIGHT
THEN VEERING TO SOUTHWEST SUNDAY MORNING. LOW LEVEL MOISTURE
RETURN OVERNIGHT...BUT ANY STRATUS SHOULD STAY TO THE SOUTH.
PREV DISCUSSION... /ISSUED 349 PM CDT SAT APR 23 2016/
SHORT TERM...
THE DRYLINE HAS BEEN SITTING IN EASTERN NM FOR SOME TIME TODAY AND
SHOULD STAY THERE...FOR THE MOST PART... UNTIL THE UPPER LEVEL LOW
PUSHES CLOSER TO THE REGION. CONVECTION ALONG THE DRYLINE STILL
LOOKS UNLIKELY AS LIFT LOOKS TO BE HARD TO COME BY. THE BEST CHANCE
FOR LIFT WOULD BE WITH THE DRYLINE. THE BEST SURFACE CONVERGENCE
ALONG THE DRYLINE IS NORTH IN THE TEXAS PANHANDLE. A LOCALIZED AREA
OF ENHANCE CONVERGENCE HAS RECENTLY SET UP OVER THE TX/NM STATE LINE
AROUND PARMER COUNTY. THIS HAS RESULTED IN A SHALLOW CU FIELD.
ENOUGH LIFT FOR ISOLATED SHOWER DEVELOPMENT IS NOT OUT OF THE
QUESTION...HOWEVER THUNDERSTORM DEVELOPMENT IS NOT HIGH ON THE
EXPECTATION LIST. THIS IS DUE TO CONVECTION HAVING TO OVERCOME A
SUBSIDENCE INVERSION IN THE UPPER-MID LEVELS AS WELL AS THERE BEING
A LACK OF CAPE. THE HRRR SEEMS TO BE THE MOST GENEROUS OF THE MODELS
IN HANDING OUT CAPE WHICH IS ONLY A COUPLE HUNDRED J/KG AT BEST
ACROSS OUR NORTHWESTERN ZONES. FOR NOW THE FORECAST WILL REFLECT A
MENTION OF ISOLATED SHOWERS BEFORE 1 AM AND NO MENTION OF THUNDER.
WINDS WILL STAY GUSTY INTO THE NIGHT AHEAD OF AND BEHIND THE
DRYLINE. WINDS WILL BE MOSTLY OUT OF THE WEST BY EARLY TOMORROW
AFTERNOON ACROSS THE CAPROCK AND WILL INCREASE TO THE 25 MPH RANGE
AS THE MAIN ENERGY FROM THE UPPER LOW PASSES TO OUR NORTH. ALDRICH
LONG TERM...
WARM...DRY AND BREEZY CONDITIONS ARE IN STORE THROUGH TUESDAY.
THE SECOND IN A SERIES OF UPPER LOWS/TROUGHS WILL SWING ACROSS THE
SOUTHERN HIGH PLAINS TUESDAY AFTERNOON...PRODUCING THE WINDIEST
DAY OF THE PERIOD. GFS MOS GUIDANCE CONTINUES TO HOVER AROUND 30
TO 34 KTS AT LUBBOCK...WHILE THE MET IS AROUND 20 KTS. WE
CONTINUE TO PLY THE MIDDLE-GROUND AT AROUND 25 KTS OR SO...OR 25
TO 30 MPH WITH GUSTS TO AROUND 40 MPH. HIGH TEMPS MONDAY AND
TUESDAY SHOULD BE IN THE 80S TO LOW 90S. WE HAVE RETAINED A SLIVER
OF T-STORM CHANCES IN THE SRN ROLLING PLAINS LATE THURSDAY...BUT
THE LATEST INDICATIONS ARE THAT THE DRYLINE WILL BE TO THE EAST OF
THE AREA...BUT IT IS NOT OUT OF THE QUESTION SOME STORMS COULD
DEVELOP IN THAT AREA AS THE DRYLINE RETREATS SOMEWHAT IN THE
EVENING. WEDNESDAY SHOULD BE SLIGHTLY COOLER AS FLOW SWITCHES TO
NORTHWEST...THEN A COLD FRONT WILL MOVE THROUGH WEDNESDAY NIGHT OR
EARLY THURSDAY. THE NEXT UPPER LOW IS STILL FORECAST TO DIG INTO
THE DESERT SOUTHEAST MIDWEEK WITH NOT MUCH CHANGE IN TRACK THE
PAST 24 HRS. SURFACE RIDGING...A STRENGTHENING SRLY LOW-LEVEL JET
AND SW FLOW ALOFT THURSDAY SHOULD RETURN GULF MOISTURE INTO THE
AREA AND ALONG WITH SOME ISENTROPIC UPGLIDE...BEGIN TO INCREASE
PRECIP CHANCES. DURING THE DAY THURSDAY THESE CHANCES MAY BE
CONFINED TO OUR SRN AND ERN COUNTIES WHERE THE DEEPER MOISTURE IS
EXPECTED TO BE NOSING IN FROM THE SOUTH. THURSDAY NIGHT INTO
FRIDAY MORNING WE COULD SEE SHOWER AND T-STORM ACTIVITY INCREASE
AS LARGE-SCALE ASCENT FROM THE UPPER LOW BEGINS TO SPREAD OVER THE
REGION. BY FRIDAY...THE MED- RANGE SOLUTIONS BEGIN TO DIVERGE WITH
THE SURFACE DETAILS AS THE GFS BRINGS A DRYLINE INTO THE AREA
WHILE THE ECMWF MAINTAINS SURFACE RIDGING. OVERALL...THE PATTERN
CERTAINLY APPEARS FAVORABLE FOR T-STORM ACTIVITY...AND POSSIBLY
SEVERE WEATHER...BUT AS USUAL THE CONFIDENCE IN THE DETAILS IS LOW
THIS FAR OUT. THE UPPER- TROUGH IS CURRENTLY EXPECTED TO PASS
ACROSS WEST TEXAS DURING THE DAY SATURDAY...DRAGGING PRECIP.
CHANCES EASTWARD WITH IT.
FIRE WEATHER...
THE FIRE DANGER WILL BECOME ELEVATED ACROSS MUCH OF THE CAPROCK
EACH AFTERNOON SUNDAY THROUGH TUESDAY. CONDITIONS WILL LIKELY BE
THE WORST ON TUESDAY AS A PASSING STORM SYSTEM BRINGS STRONGER
WIND SPEEDS. HOWEVER...THE OVERALL FIRE DANGER WILL BE REDUCED BY
THE SEASONAL GREEN-UP ACROSS THE AREA.
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
949 PM CDT MON APR 25 2016
.UPDATE...
AXIS OF HIGHER DEW POINTS HAS SHIFTED EAST OF AREA AHEAD OF
SURFACE LOW NOW CENTERED OVER SRN LAKE MICHIGAN ENDING THE SEVERE
WEATHER THREAT. AN ISOLATED SHOWER STILL POSSIBLE LATE THIS
EVENING ALONG COLD FRONT/SURFACE TROUGH AS IT SAGS THROUGH THE
REMAINDER OF THE CWA OVERNIGHT IN THE WAKE OF THE LOW. MOSTLY
CLEAR SKIES WILL BE REPLACED BY STRATUS DECK BEHIND THE COLD
FRONT. LATEST NAM SUPPORTS GOING FORECAST WITH EVERYONE FALLING
INTO THE 40S BY MORNING ON NORTH TO NORTHEAST WINDS.
&&
.AVIATION/06Z TAFS/...
LOOKING FOR VFR CONDITIONS UNTIL IFR STRATUS OVERSPREADS ALL OF
SOUTHERN WISCONSIN LATE TONIGHT BEHIND A COLD FRONT/SURFACE TROUGH
THAT IS CURRENTLY ALONG A WEST BEND...JUNEAU...PORTAGE TO THE
DELLS LINE. CURRENT TIMING BRINGS THE LOW CLOUDS DOWN TO A LONE
ROCK...MADISON TO MILWAUKEE LINE AROUND 0430Z TO 05Z...AND TO THE
ILLINOIS BORDER BETWEEN 06Z AND 07Z...WITH THE LATER TIME OVER THE
SW. COULD SEE SOME LOCATIONS DROP TO BELOW ALTERNATE MINIMUMS IN
THE EAST WITH THE COOL NORTH TO NORTHEAST FLOW OFF OF LAKE
MICHIGAN ALONG WITH SOME PATCHY DRIZZLE. SHOULD LIFT CLOUDS BACK
UP TO MVFR LEVELS OVER WESTERN AREAS AROUND MID-MORNING...BUT
EASTERN LOCATIONS WILL NOT REACH THOSE LEVELS UNTIL MIDDAY OR
EARLY AFTERNOON. EXPECT VFR CIGS BY EARLY AFTERNOON WEST AND LATE
AFTERNOON EAST.
&&
.MARINE...
SLOW MOVEMENT OF SURFACE TROUGH/COLD FRONT WILL KEEP NORTHERLY
GUSTS FROM REACHING SMALL CRAFT ADVISORY LEVELS UNTIL AFTER 08Z IN
THE NORTH AND 11Z OR 12Z IN THE SOUTH. CURRENT TIMING OF SMALL
CRAFT ADVISORIES LOOKS ON TRACK AND SUPPORTED BY LATEST NAM
SOUNDINGS.
&&
.PREV DISCUSSION... /ISSUED 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...REM
TONIGHT/TUESDAY AND AVIATION/MARINE...MRC
TUESDAY NIGHT THROUGH MONDAY...DAVIS
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
332 AM EDT TUE APR 26 2016
.DISCUSSION...
...MODERATE RIP CURRENT RISK TODAY AT EAST CENTRAL FLORIDA BEACHES...
TODAY...NW FLOW ALOFT WILL CONTINUE TODAY ON THE BACK SIDE OF A
MID/UPR LVL S/W TROUGH THAT WILL MOVE EAST OF THE STATE OVER THE
ATLC THROUGH THE MORNING HOURS. 00Z CAPE SOUNDING INDICATED A DRY
AIRMASS WITH PWAT OF .91 INCHES WITH COOL MID LVL TEMPS ASSOCIATED
WITH THE TROUGH ALOFT TO -13 DEGS C AT H5. SOME WARMING OF THE
MID LVLS IS FCST THIS AFTERNOON AS H5 TEMPS WARM TO -10 C. LIGHT SE
FLOW THIS MORNING AROUND THE ATLC RIDGE WILL BACK SOME TO THE ESE/E
THIS AFTERNOON WITH THE EAST COAST SEA BREEZE MOVING INLAND WITH THE
PREVAILING LOW LVL FLOW. MOST OF THE SHORT RANGE GUID TODAY INDICATES
CONVECTION AGAIN WEST OF THE E CENTRAL FL FOCUSED CLOSER TO THE WEST
COAST SEA BREEZE IN THE LATE AFTERNOON. WILL CONTINUE LOW SHOWER
CHANCES ACROSS FAR SRN SECTIONS THIS MORNING AND WELL INTERIOR
SECTIONS LATER THIS AFTERNOON BUT WITH DRY FCSTS FROM THE 00Z GFS
AND ECMWF AND ALSO 04Z HRRR EXPERIMENTAL RUN NOT EXPECTING MUCH
COVERAGE. 00Z NAM AGAIN APPEARS TO BE AN OUTLIER WITH SOME HEAVIER
QPF NEAR ORLANDO IN THE AFTN. A MODERATE RISK OF RIP CURRENTS IS
EXPECTED WITH A NE SWELL AT THE BEACHES. HIGHS IN THE LOWER 80S
COASTAL TO MID 80S OVER THE INTERIOR.
TONIGHT...SE FLOW WILL CONTINUE AROUND THE ATLC RIDGE WITH ANY
EVENING CONVECTION EXPECTED TO BE WEST OF THE AREA. LOWS WILL BE IN
THE 60S WITH MOSTLY CLEAR TO PARTLY CLOUDY SKIES.
WED-THU...WEAK RIDGING ALOFT IS FORECAST TO CONTINUE WHILE AXIS OF
ATLANTIC SURFACE HIGH PRESSURE RIDGE WILL EXTEND ACROSS THE
PENINSULA. THIS WILL RESULT IN AN EXTENDED PERIOD OF ONSHORE WINDS.
TIME HEIGHT CROSS SECTIONS INDICATE THAT MOST IF NOT ALL THE
MOISTURE WILL BE IN THE SURFACE TO 5000 FEET (850MB) LAYER AND A DRY
SUBSIDENT AIR MASS ABOVE 10000 FEET (700MB). LIGHT WINDS EACH NIGHT
WITH AN EAST COAST SEA BREEZE EACH AFTERNOON MOSTLY CLEAR TO PARTLY
SUNNY SKIES WILL ALLOW AN EAST COAST SEA BREEZE TO FORM AND PUSH
INLAND EACH DAY. THE AIR MASS WILL REMAIN QUITE DRY AND ONSHORE LOW
LEVEL FLOW LOOKS SHALLOW/WEAK...SO ANY SEA BREEZE CONVECTION SHOULD
BE LATE IN THE DAY AND OVER THE WEST SIDE OF THE PENINSULA. GUIDANCE
CAME IN WITH POP LESS THAN 15 PERCENT WHICH WOULD BE LOWER THAN
CURRENT POP. RATHER THAN HAVE SUCH LOW POP BOUNCE AROUND DID NOT
STRAY FAR FROM CURRENT POP OF 20 PERCENT OR LESS. MOSTLY CLEAR TO
PARTLY SUNNY SKIES AND LIGHT WINDS WILL ALLOW AFTERNOON HIGHS TO
REACH IN THE LOWER 80S AT THE COAST AND THE MID TO UPPER 80S FOR THE
INTERIOR.
FRI-SUN...RIDGING ALOFT BUILDS THROUGH THE WEEKEND AS TROUGHING OVER
THE ROCKIES MOVES INTO SOUTHEAST U.S. AMD GULF COAST. TIME HEIGHT
CROSS SECTIONS CONTINUE TO DEPICT SHALLOW MOISTURE AND EASTERLY
WINDS. DRY FORECAST TO CONTINUE. HIGHS IN THE MID AND UPPER 80S AND
LOW IN THE MID 60S.
MON...TROUGH/WEAK FRONT MOVING ACROSS THE SOUTHEAST U.S. PUSHES THE
SURFACE/LOW LEVEL RIDGES TO THE SOUTHEAST FAR ENOUGH FOR A WIND
SHIFT TO THE SOUTH. SOUTHERLY FLOW DRAWS ENOUGH MOISTURE BACK INTO
CENTRAL FLORIDA FOR A SLIGHT CHANCE OF MAINLY AFTERNOON STORMS OVER
THE INTERIOR. HIGHS MID 80S AND LOW IN THE LOW AND MID 60S.
TUE...SURFACE RIDGE IS PUSHED TO THE SOUTHEAST BY TROUGH ADVANCING
ACROSS THE LOWER MISSISSIPPI RIVER VALLEY INTO THE SOUTHEAST U.S.
TIME HEIGHT CROSS SECTIONS SHOW MORE...BUT LIMITED...MOISTURE AHEAD
OF THE FRONT WITH SLIGHTLY BETTER MID AND UPPER LEVEL LIFT AND
VORTICITY TO GO WITH SOME AFTERNOON STORMS AND A SLIGHT CHANCE OF
EVENING SHOWERS. HIGHS MID 80S...LOWS MID AND UPPER 60S.
&&
.AVIATION...
VFR CONDS EXPECTED WITH SCATTERED CUMULUS FOR SRN TERMINALS AND THE
INTERIOR TERMINALS WITH DAYTIME HEATING. HAVE VCSH STUART TERMINAL
15Z-18Z WHICH MAY BE GENEROUS. OTHER TERMINALS WILL KEEP DRY. ANY
LATE DAY SHOWER ACTIVITY EXPECTED TO BE WEST OF KMCO-KSFB CORRIDOR.
WITH ONLY A SLIGHT CHANCE FOR A LATE DAY SHOWER AT KLEE-KISM HAVE
LEFT PRECIP MENTION OUT OF FCST.
&&
.MARINE...
TODAY-TONIGHT...SE WINDS 5-10 KNOTS WILL INCREASE TO AROUND 10 KNOTS
BY THIS AFTERNOON AND 10-15 KNOTS TONIGHT. SEAS 3 FT NEARSHORE TO 4
FT OFFSHORE IN A NE SWELL.
TUESDAY...RIDGE AXIS NORTH OF THE AREA WILL PRODUCE E/SE WINDS OVER
THE COASTAL WATERS WITH SPEEDS LESS THAN 15 KNOTS. SEAS WILL RANGE
FROM 2-4 FEET.
WED-SAT...AXIS OF THE ATLANTIC HIGH PRESSURE RIDGE REMAINS EITHER
OVER AND JUST TO THE NORTH OF CENTRAL FLORIDA. EXCEPT FOR OFFSHORE
WINDS FRI AS A WEAK FRONT/TROUGH TRACKS EAST OVER THE SOUTHEAST U.S.
EAST TO SOUTHEAST WINDS LESS THAN 15 KNOTS PREVAIL. SEAS 3 TO 4 FEET
OFFSHORE AND 3 FEET AND LESS NEARSHORE.
&&
.FIRE WEATHER...
MIN RHS TO 40-45 PCT ACROSS THE INTERIOR THE NEXT SEVERAL AFTERNOONS
WITH WINDS GENERALLY LESS THAN 15 MPH...EXCEPT UP TO 15 MPH WITH THE
SEA BREEZE CIRCULATION EACH AFTERNOON. NO HEADLINES EXPECTED THOUGH
ERC VALUES WILL CONTINUE TO CREEP UP WITH DRY WEATHER INTO LATE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 82 65 84 65 / 0 0 10 0
MCO 86 67 88 67 / 10 10 20 0
MLB 82 67 83 66 / 10 10 10 0
VRB 83 65 84 64 / 10 10 10 0
LEE 86 68 87 69 / 20 10 20 10
SFB 85 66 86 67 / 10 10 10 10
ORL 85 68 86 68 / 10 10 20 10
FPR 82 64 84 63 / 10 10 20 0
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM/AVIATION...VOLKMER
LONG TERM....WIMMER
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
109 AM CDT TUE APR 26 2016
.UPDATE...
903 PM CDT
HAVE CLEARED SOME OF THE NORTH/NORTHWEST COUNTIES AND MARINE ZONES
FROM SEVERE THUNDERSTORM WATCH 103...GENERALLY NORTHWEST OF A
MENDOTA TO HIGHLAND PARK LINE AS OF 9 PM CDT.
WHILE INSTABILITY IS DIMINISHING AFTER SUNSET...ISOLATED
THUNDERSTORMS CONTINUE TO FESTER IN CONVERGENCE ZONE ALONG A
SOUTHWEST-NORTHEAST ORIENTED BOUNDARY NOTED IN RADAR IMAGERY FROM
NORTHWEST LASALLE CO TO NORTHEAST COOK CO. SPC RAP-BASED MESOANALYSIS
INDICATES 40-50 KT OF EFFECTIVE DEEP LAYER SHEAR WITHIN REGION OF
1000-1500 J/KG CAPE AXIS SOUTHEAST OF THIS BOUNDARY...AND WHILE
STORMS ARE LIKELY BECOMING ELEVATED...THE POTENTIAL FOR ISOLATED
LARGE/SEVERE HAIL WILL CONTINUE FOR AT LEAST THE NEXT HOUR OR SO.
THUS WILL MAINTAIN REMAINING PORTIONS OF 103 UNTIL EXPIRATION.
AS FOR OVERNIGHT FORECAST...HAVE ADJUSTED POPS/WX BASED ON LATEST
OB/RADAR TRENDS TO TIGHTEN UP THE TRAILING PORTION OF THE
GRADIENT. ALSO TWEAKED HOURLY TEMP/DEW POINTS ACCOUNT POSITION OF
THE BOUNDARY. NO OTHER CHANGES MADE AT THIS TIME.
RATZER
&&
.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 06Z TAFS...
THUNDERSTORMS NO LONGER POSE A THREAT TO THE TERMINALS. HOWEVER
THE COLD FRONT IS STEADILY ADVANCING SOUTH. YOU CAN SEE THE FRONT
ON RADAR PUSHING SOUTHWEST. WINDS BECOME NE LESS THAN 10 KT
BEHIND IT INITIALLY BUT EXPECTING WIND SPEEDS TO INCREASE TO 10-15
KT THIS MORNING. LIFR STRATUS IS ALSO LAGGING BEHIND THE FRONT.
LUCKILY THE STRATUS AND FOG OVER THE LAKE ARE REMAINING OVER THE
LAKE AND NOT SPREADING TOO FAR ONSHORE. EXPECTING AN INITIAL WIND
SHIFT TO NE WITHIN THE NEXT FEW HOURS AT THE EASTERN
TERMINALS...AND THEN THE STRATUS SHOULD BUILD IN A FEW HOURS
LATER. GYY AND RFD ARE THE EXCEPTION. THINKING THE LAKE STRATUS
WILL MOVE OVER GYY WITH THE WIND SHIFT TO N OR NNE EARLY THIS
MORNING. ALSO THINKING THE STRATUS AND WIND SHIFT WILL OCCUR
SIMULTANEOUSLY AT RFD. I HAVE HIGH ENOUGH CONFIDENCE TO GO WITH
500 FT CIGS INITIALLY. COULD SEE EVEN LOWER CIGS AS MANY SITES IN
WI ARE BELOW 500 FT. NOT EXPECTING ANY FOG AT THE TERMINALS.
GUIDANCE DIFFERS ON HOW CIGS WILL BEHAVE TODAY. LEANING TOWARD A
MORE PESSIMISTIC OUTLOOK WITH CIGS RISING TO MVFR LATE THIS
MORNING AND REMAINING MVFR THROUGH THE PERIOD. IT IS POSSIBLE THAT
CIGS RISE TO VFR THIS AFTN OR EVENING. HAVE HIGH CONFIDENCE IN
THICK CLOUD COVER AND CIG TRENDS THROUGH THE PERIOD...BUT ONLY
MEDIUM CONFIDENCE IN MVFR THIS AFTN AND EVENING AS WE MAY BE VFR.
JEE
&&
.MARINE...
255 PM CDT
A QUICK MOVING SURFACE LOW IS EXPECTED TO MOVE ACROSS SOUTHERN
LAKE MICHIGAN TONIGHT. THIS SYSTEM LOOKS TO SPAWN SOME
THUNDERSTORM ACTIVITY EARLY THIS EVENING OVER SOUTHERN PORTIONS OF
THE LAKE. SOME OF THESE STORMS COULD BE SEVERE WITH STRONG WIND
GUSTS AND HAIL. OTHERWISE...FARTHER NORTH...EXPECT 30 TO SOME 35
KT EAST-NORTHEASTERLY GALES TO PERSIST TONIGHT BEFORE ABATING
LATE.
NORTHERLY FLOW IS EXPECTED TO SET UP LAKE-WIDE ON TUESDAY IN THE
WAKE OF TONIGHTS LOW. ONCE THIS OCCURS...IT LOOKS LIKE THERE WILL
BE A PROLONGED PERIOD OF EAST-NORTHEASTERLY FLOW OVER LAKE
MICHIGAN THROUGH THE REST OF THE WEEK...AND POSSIBLY THROUGH THE
UPCOMING WEEKEND AS WELL. DURING THIS PERIOD...SURFACE HIGH
PRESSURE IS EXPECTED TO DOMINATE OVER SOUTHERN CANADA AND THE
UPPER GREAT LAKES REGION...WHILE A COUPLE OF LOW PRESSURE SYSTEMS
TRACK EASTWARD SOUTH OF THE LAKES. EACH OF THESE LOWS WILL LIKELY
RESULT IN A PERIOD OF STRONGER EAST-NORTHEASTERLY FLOW OVER THE
LAKE. THE FIRST ONE EXPECTED TO IMPACT THE LAKE WEDNESDAY INTO
THURSDAY...THEN THE SECOND LOW IS POSSIBLE OVER THE WEEKEND. WHILE
GALE FORCE WINDS ARE CURRENTLY NOT ANTICIPATED...SOME 25 TO 30 KT
FLOW WILL LIKELY RESULT IN LARGE WAVES AND SMALL CRAFT CONDITIONS
OVER THE SOUTHERN LAKE MICHIGAN NEAR SHORES.
KJB
&&
.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
1153 PM CDT MON APR 25 2016
.UPDATE...
Issued at 922 PM CDT Mon Apr 25 2016
Boundary is finally moving through the CWA this evening. Will need
to update pop/wx grids to account for current situation and
trends. Based on radar, isolated showers and thunderstorms will
continue to move through the CWA, mainly east of I-55. Boundary is
hard to see in the observations but it can be seen on radar just
passing the NWS office and is just east of I-55. This movement
will continue through the night, which means the showers could as
well. Other updates will be needed to account for the scattered
clouds in the west behind the boundary. Update forthcoming.
&&
.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 06Z TAFS through 06Z Tuesday night)
Issued at 1153 PM CDT Mon Apr 25 2016
VFR conditions will prevail at all TAF sites next 24hrs. Sct to
bkn clouds at around 5-6kft will continue over the area and then
become all scattered in a few hours at all sites. However,
additional moisture will increase along the boundary that is
slowly moving through the area. By morning this will bring broken
cigs around 4kft at all sites. These broken cigs will continue
over the area through remainder of the forecast period. With the
frond just south of sites, any pcpn along the front should remain
south of the TAF sites as well. Winds will be tricky as the front
will be fairly stationary near I-72, so PIA/BMI and then CMI will
see winds become more northeast after FROPA. SPI and DEC should
see variable winds through most of the period, but then become
more southwest for the afternoon and evening periods.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Auten
SHORT TERM...Geelhart
LONG TERM...BAK
AVIATION...Auten
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
427 AM EDT TUE APR 26 2016
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 339 AM EDT TUE APR 26 2016
AN UNSETTLED WEATHER PATTERN WITH THE POTENTIAL FOR SHOWERS AND
THUNDERSTORMS WILL CONTINUE THROUGH THURSDAY AS A FRONTAL BOUNDARY
OSCILLATES ACROSS THE OHIO VALLEY. AFTER A BRIEF PERIOD OF DRY
WEATHER TO END THE WEEK...WETTER CONDITIONS WILL RETURN FOR THE
WEEKEND AS LOW PRESSURE TRACKS THROUGH THE REGION. AN UPPER LOW WILL
MOVE INTO THE GREAT LAKES EARLY NEXT WEEK...BRINGING COOL WET
WEATHER TO CENTRAL INDIANA.
&&
.NEAR TERM /TODAY/...
ISSUED AT 339 AM EDT TUE APR 26 2016
PARTLY CLOUDY SKIES AND BREEZY CONDITIONS ONGOING EARLY THIS MORNING
WITH SOUTHWEST WINDS REMAINING AT A STEADY 10-20MPH AS LOW PRESSURE
TRACKS THROUGH THE LOWER GREAT LAKES. MOST OF THE CONVECTION IS IN
CLOSEST PROXIMITY TO THE LOW...EXTENDING ACROSS THE EASTERN GREAT
LAKES BACK INTO NORTHEAST INDIANA. WITH WELL MIXED AIR IN THE
BOUNDARY LAYER...TEMPS HAVE NOT MOVED MUCH SO FAR DURING THE
OVERNIGHT...WITH 07Z TEMPS GENERALLY IN THE MID AND UPPER 60S.
PRIMARY FOCUS FOR TODAY IS ON THE POTENTIAL FOR REDEVELOPING
CONVECTION WHILE SIFTING THROUGH THE MODEL SUITE WHICH CONTINUES TO
CARRY POOR RUN TO RUN CONTINUITY. HAVE LEANED MUCH CLOSER TO THE HI-
RES GUIDANCE /HRRR-WRF-4KM NAM/ FOR TIMING CONVECTIVE DEVELOPMENT
AND LOCATION OF GREATEST COVERAGE LATER TODAY.
COLD FRONT EXTENDS W/SW ACROSS NW INDIANA AND NORTH CENTRAL ILLINOIS
FROM THE SURFACE LOW CURRENTLY OVER SOUTHEAST MICHIGAN. MOST OF THE
FORCING ALOFT IS IN THE VICINITY OF THE SURFACE WAVE WITH THE LOW
LEVEL JET ALREADY DEPARTING INTO THE EASTERN GREAT LAKES. THIS HAS
RESULTED IN CONVECTION REMAINING ISOLATED AT BEST WITH LITTLE TO
FIRE OFF OF BACK TO THE NORTHWEST OF THE AREA SO FAR THIS MORNING.
FURTHERMORE...MODELS HAVE NOT HANDLED THE PRESENCE OF THE DRIER
AIRMASS OVER CENTRAL INDIANA WELL AT ALL...CONSISTENTLY TRYING TO
ADVECT LOW LEVEL MOISTURE INTO THE REGION FASTER THAN WHAT IS
ACTUALLY OCCURRING. MESOANALYSIS SHOWS THIS VERY CLEARLY WITH A
BORDERLINE HOSTILE ENVIRONMENT PRESENT OVER THE FORECAST AREA
HIGHLIGHTED BY DEWPOINTS PRIMARILY IN THE LOWER/MID 50S AND AN
ABUNDANCE OF CONVECTIVE INHIBITION. AS A RESULT...EVEN SHOWERS HAVE
HAD A DIFFICULT TIME MAKING IT INTO THE REGION SO FAR EARLY THIS
MORNING.
WHILE CONVECTIVE INHIBITION WILL SLOWLY DIMINISH THROUGH THE MORNING
AS MOISTURE SLOWLY INCREASES...HAVE A HARD TIME JUSTIFYING ANY
HIGHER THAN A 20 POP WITH RIDGING ALOFT DEVELOPING. THE PRESENCE OF
THE FRONTAL BOUNDARY SLIPPING SOUTH INTO THE NORTHERN HALF OF THE
FORECAST AREA BY LATE MORNING REALLY IS THE ONLY FEATURE LIKELY TO
PRODUCE ANYTHING OF SUBSTANCE THROUGH MIDDAY.
AS THE FRONT SHIFTS INTO THE SOUTHERN HALF OF THE FORECAST AREA THIS
AFTERNOON HOWEVER...THE SETUP WILL BECOME MUCH MORE CONDUCIVE FOR
THUNDERSTORMS AS MOISTURE POOLS ALONG THE BOUNDARY AND THE AIRMASS
BECOMES MODESTLY UNSTABLE WITH STEEPENING LAPSE RATES. A WAVE ALOFT
THAT IS CURRENTLY GENERATING INITIAL CONVECTIVE DEVELOPMENT IN THE
MISSOURI VALLEY EARLY THIS MORNING WILL ROUND THE UPPER RIDGE AND
SWING INTO THE REGION BY LATE AFTERNOON. THIS FEATURE WILL ADD SOME
FORCING FOR MORE ORGANIZED CONVECTIVE DEVELOPMENT WITH BULK OF THE
HI-RES GUIDANCE ALL CAPTURING AREAS OF THUNDERSTORMS DEVELOPING AND
BECOMING MOST NUMEROUS ALONG AND SOUTH OF I-70. WILL CONTINUE WITH
HIGHEST POPS IN THESE AREAS...TAPERING OFF QUICKLY OVER NORTHERN
COUNTIES AS DRIER AIR FILTERS IN NORTH OF THE FRONT. LACK OF MORE
APPRECIABLE BL SHEAR AND UNIMPRESSIVE BOUNDARY LAYER FLOW SUPPORT
MORE OF A MULTICELLULAR MODE TO STORMS WITH PULSING INTENSITY. COULD
SEE STRONGER STORMS PRODUCE HAIL AND BRIEF WIND GUSTS BUT OVERALL
EXPECT STORMS TO REMAIN SUBSEVERE INTO THE EVENING.
TEMPS...CONSIDERING THE WARMER START THIS MORNING WHICH MOST OF THE
MODELS HAVE MISSED...AND THE POTENTIAL FOR SUN AND QUICK HEATING
THROUGH THE FIRST HALF OF THE DAY...TRENDED HIGH TEMPS TOWARDS
HRRR/4KM NAM WHICH PLACE MOST AREAS AT OR A COUPLE DEGREES WARMER
THAN MOS. EXPECT MID 70S NORTH TO LOWER 80S SOUTH.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
ISSUED AT 339 AM EDT TUE APR 26 2016
FORECAST CHALLENGES FOCUS ON PRECIP CHANCES THROUGH MUCH OF THE
PERIOD...AND POTENTIAL IMPACTS TO TEMPS AS LOCATION OF THE
OSCILLATING FRONTAL BOUNDARY WILL CREATE SHARP GRADIENTS FROM NORTH
TO SOUTH ACROSS THE FORECAST AREA AT TIMES.
CONVECTION LIKELY TO BE ONGOING AT 00Z THIS EVENING NEAR THE FRONTAL
BOUNDARY OVER THE SOUTHERN HALF OF THE FORECAST AREA. THE BOUNDARY
WILL CONTINUE TO PRESS INTO FAR SOUTHERN INDIANA LATE TONIGHT AIDED
BY BROAD HIGH PRESSURE OVER THE NORTHERN GREAT LAKES. ANY SCATTERED
CONVECTION WILL SHIFT TO THE LOWER WABASH VALLEY AND PERHAPS FAR
SOUTHERN ROW OF COUNTIES AFTER MIDNIGHT AS E/NE FLOW BRINGS DRIER
AIR BACK SOUTH INTO MUCH OF THE REGION. SHALLOW LAYER OF COOLER AIR
IN THE NEAR SURFACE LAYER WILL LEAD TO A SHARP INVERSION DEVELOPING
LATE TONIGHT AND CONTINUING INTO WEDNESDAY MORNING. THIS WILL LIKELY
MANIFEST AS A THICK LAYER OF STRATUS AND WILL CONTINUE WITH MOSTLY
CLOUDY SKIES ACROSS MUCH OF THE AREA.
FOCUS WILL SHIFT TO THE DEEP UPPER LOW AND ATTENDANT SURFACE WAVE
LIFTING NORTH THROUGH THE CENTRAL PLAINS WEDNESDAY MORNING. THIS
WILL PROMPT THE BOUNDARY TO LIFT BACK NORTH AS A WARM FRONT WHILE
THE LOW PRESSURE OCCLUDES OVER THE MISSOURI VALLEY. THESE FEATURES
WILL BE THE PRIMARY CATALYSTS IN THE POTENTIAL SIGNIFICANT SEVERE
WEATHER EXPECTED LATE TODAY AND TONIGHT OVER THE CENTRAL AND
SOUTHERN PLAINS. THAT ACTIVITY IS LIKELY TO COALESCE INTO A LINE OR
LINES OF WEAKER CONVECTION OVERNIGHT INTO WEDNESDAY MORNING AS IT
PRESSES EAST INTO THE MID MISSISSIPPI VALLEY AND LOWER OHIO VALLEY.
REMNANTS FROM THESE STORMS WILL GET DRAWN INTO THE REGION BY
WEDNESDAY AFTERNOON AS THE WARM FRONT LIFTS NORTH...AND MAY EVEN SEE
SOME RESTRENGTHENING OF STORMS LATE DAY IN THE LOWER WABASH VALLEY
WHERE ACTIVITY HAS BEST CHANCE TO BECOME SURFACE BASED IN THE WARM
SECTOR. NICE DIFFLUENCE ALOFT WILL HELP TO ENHANCE CONVECTIVE
COVERAGE WITH RAIN AND STORMS BECOMING WIDESPREAD FROM LATE
AFTERNOON INTO WEDNESDAY NIGHT. WILL CONTINUE WITH HIGH POPS ACROSS
THE FORECAST AREA AS A RESULT.
THE OCCLUDING SURFACE LOW WILL KICK OUT INTO THE REGION THURSDAY AS
THE UPPER LOW OPENS UP AND TRACKS INTO THE GREAT LAKES. DEEPER
MOISTURE AND BETTER FORCING SUPPORTS CARRYING BEST CHANCE POPS
ACROSS THE NORTHEAST HALF OF THE FORECAST AREA THURSDAY. SCATTERED
SHOWERS WILL GRADUALLY END THURSDAY EVENING AS THE LOW MOVES AWAY TO
THE EAST AND UPPER RIDGING QUICKLY EXPANDS INTO THE OHIO VALLEY.
TEMPS...WITH THE FRONT IN SOUTHERN COUNTIES WEDNESDAY...EXPECT A
FAIRLY SHARP TEMP GRADIENT FROM THE LOWER 60S IN THE NORTHEAST TO
THE MID 70S IN THE LOWER WABASH VALLEY. WARMER TEMPS EXPECTED
THURSDAY AND FAR SOUTHERN COUNTIES MAY MAKE A RUN AT 80 DEGREES WITH
MORE SUNSHINE AND ONLY WIDELY SCATTERED CONVECTION ANTICIPATED. AN
OVERALL MODEL BLEND CAPTURED THIS THINKING WELL. GENERALLY TRENDED
TOWARDS WARMER MAVMOS FOR LOWS THROUGH THE PERIOD.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
ISSUED AT 242 AM EDT TUE APR 26 2016
MODELS ARE CLOSE ENOUGH THAT THE SUPERBLEND INITIALIZATION WAS
ACCEPTED FOR MOST ITEMS.
AN UPPER LEVEL LOW INITIALLY OVER THE WESTERN HALF OF THE COUNTRY
WILL WORK SLOWLY EAST INTO THE REGION THROUGH THE LONG TERM. THIS
WILL ALSO BRING A SURFACE LOW PRESSURE SYSTEM WITH IT. THE RESULT OF
THIS SETUP WILL BE FREQUENT CHANCES FOR RAIN THROUGH THE LONG TERM.
GFS IS FASTER THAN ECMWF/CANADIAN IN BRINGING A RETURN OF RAIN
FRIDAY NIGHT. STUCK WITH THE CONSENSUS OF THE ECMWF/CANADIAN AND CUT
BACK SUPERBLEND/S POPS FRIDAY NIGHT. THIS IS CLOSE TO THE PREVIOUS
FORECAST AND THUS AVOIDS POTENTIAL FLIP-FLOPPING.
TEMPERATURES WILL START OUT NEAR AVERAGE...BUT WILL END UP COOLING
TO BELOW AVERAGE LATE IN THE PERIOD AS THE UPPER LOW MOVES IN.
&&
.AVIATION /DISCUSSION FOR 260900Z TAF UPDATE/...
ISSUED AT 427 AM EDT TUE APR 26 2016
LOOKS LIKE MVFR CEILINGS MAY NOT DEVELOP AFTER ALL...PER LATEST
CONSENSUS SHORT TERM GUIDANCE AND LATEST OBSERVATIONS. CONFIDENCE IS
STILL LOW TO MEDIUM AT BEST THOUGH. HAVE REMOVED MVFR CEILINGS THIS
MORNING FROM THE TAFS.
PREVIOUS DISCUSSION FOLLOWS...
MODERATE CONFIDENCE THAT VFR CONDITIONS WILL DETERIORATE TO MVFR IN
THE 10Z-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 EXCEPT PERHAPS BRIEFLY AT THE ONSET AT LAF PER
RADAR TRENDS. THE ONCE WIDESPREAD HRRR REFLECTIVITY PROGS ARE NOW
EVEN HINTING AT SMALL COVERAGE AT BEST. THINK THE BETTER CHANCE FOR
CONVECTION WILL BE THIS AFTERNOON AS THE FRONTAL BOUNDARY WORKS ITS
WAY SOUTH ACROSS CENTRAL INDIANA. WOULD NOT RULE OUT MORE ACTIVITY
TONIGHT...BUT AGAIN COVERAGE LOOKS TOO LOW TO MENTION.
WINDS WILL BE SOUTHWEST 6 TO 10 KNOTS OVERNIGHT AND WEST AND
NORTHWEST LESS THAN 10 KNOTS IN THE WAKE OF THE FRONT AFTER DAYBREAK.
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 UNTIL
SHORTLY AFTER 00Z TONIGHT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....50
AVIATION...MK/50
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
339 AM EDT TUE APR 26 2016
.UPDATE...
THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN UPDATED
BELOW.
&&
.SYNOPSIS...
ISSUED AT 339 AM EDT TUE APR 26 2016
AN UNSETTLED WEATHER PATTERN WITH THE POTENTIAL FOR SHOWERS AND
THUNDERSTORMS WILL CONTINUE THROUGH THURSDAY AS A FRONTAL BOUNDARY
OSCILLATES ACROSS THE OHIO VALLEY. AFTER A BRIEF PERIOD OF DRY
WEATHER TO END THE WEEK...WETTER CONDITIONS WILL RETURN FOR THE
WEEKEND AS LOW PRESSURE TRACKS THROUGH THE REGION. AN UPPER LOW WILL
MOVE INTO THE GREAT LAKES EARLY NEXT WEEK...BRINGING COOL WET
WEATHER TO CENTRAL INDIANA.
&&
.NEAR TERM /TODAY/...
ISSUED AT 339 AM EDT TUE APR 26 2016
PARTLY CLOUDY SKIES AND BREEZY CONDITIONS ONGOING EARLY THIS MORNING
WITH SOUTHWEST WINDS REMAINING AT A STEADY 10-20MPH AS LOW PRESSURE
TRACKS THROUGH THE LOWER GREAT LAKES. MOST OF THE CONVECTION IS IN
CLOSEST PROXIMITY TO THE LOW...EXTENDING ACROSS THE EASTERN GREAT
LAKES BACK INTO NORTHEAST INDIANA. WITH WELL MIXED AIR IN THE
BOUNDARY LAYER...TEMPS HAVE NOT MOVED MUCH SO FAR DURING THE
OVERNIGHT...WITH 07Z TEMPS GENERALLY IN THE MID AND UPPER 60S.
PRIMARY FOCUS FOR TODAY IS ON THE POTENTIAL FOR REDEVELOPING
CONVECTION WHILE SIFTING THROUGH THE MODEL SUITE WHICH CONTINUES TO
CARRY POOR RUN TO RUN CONTINUITY. HAVE LEANED MUCH CLOSER TO THE HI-
RES GUIDANCE /HRRR-WRF-4KM NAM/ FOR TIMING CONVECTIVE DEVELOPMENT
AND LOCATION OF GREATEST COVERAGE LATER TODAY.
COLD FRONT EXTENDS W/SW ACROSS NW INDIANA AND NORTH CENTRAL ILLINOIS
FROM THE SURFACE LOW CURRENTLY OVER SOUTHEAST MICHIGAN. MOST OF THE
FORCING ALOFT IS IN THE VICINITY OF THE SURFACE WAVE WITH THE LOW
LEVEL JET ALREADY DEPARTING INTO THE EASTERN GREAT LAKES. THIS HAS
RESULTED IN CONVECTION REMAINING ISOLATED AT BEST WITH LITTLE TO
FIRE OFF OF BACK TO THE NORTHWEST OF THE AREA SO FAR THIS MORNING.
FURTHERMORE...MODELS HAVE NOT HANDLED THE PRESENCE OF THE DRIER
AIRMASS OVER CENTRAL INDIANA WELL AT ALL...CONSISTENTLY TRYING TO
ADVECT LOW LEVEL MOISTURE INTO THE REGION FASTER THAN WHAT IS
ACTUALLY OCCURRING. MESOANALYSIS SHOWS THIS VERY CLEARLY WITH A
BORDERLINE HOSTILE ENVIRONMENT PRESENT OVER THE FORECAST AREA
HIGHLIGHTED BY DEWPOINTS PRIMARILY IN THE LOWER/MID 50S AND AN
ABUNDANCE OF CONVECTIVE INHIBITION. AS A RESULT...EVEN SHOWERS HAVE
HAD A DIFFICULT TIME MAKING IT INTO THE REGION SO FAR EARLY THIS
MORNING.
WHILE CONVECTIVE INHIBITION WILL SLOWLY DIMINISH THROUGH THE MORNING
AS MOISTURE SLOWLY INCREASES...HAVE A HARD TIME JUSTIFYING ANY
HIGHER THAN A 20 POP WITH RIDGING ALOFT DEVELOPING. THE PRESENCE OF
THE FRONTAL BOUNDARY SLIPPING SOUTH INTO THE NORTHERN HALF OF THE
FORECAST AREA BY LATE MORNING REALLY IS THE ONLY FEATURE LIKELY TO
PRODUCE ANYTHING OF SUBSTANCE THROUGH MIDDAY.
AS THE FRONT SHIFTS INTO THE SOUTHERN HALF OF THE FORECAST AREA THIS
AFTERNOON HOWEVER...THE SETUP WILL BECOME MUCH MORE CONDUCIVE FOR
THUNDERSTORMS AS MOISTURE POOLS ALONG THE BOUNDARY AND THE AIRMASS
BECOMES MODESTLY UNSTABLE WITH STEEPENING LAPSE RATES. A WAVE ALOFT
THAT IS CURRENTLY GENERATING INITIAL CONVECTIVE DEVELOPMENT IN THE
MISSOURI VALLEY EARLY THIS MORNING WILL ROUND THE UPPER RIDGE AND
SWING INTO THE REGION BY LATE AFTERNOON. THIS FEATURE WILL ADD SOME
FORCING FOR MORE ORGANIZED CONVECTIVE DEVELOPMENT WITH BULK OF THE
HI-RES GUIDANCE ALL CAPTURING AREAS OF THUNDERSTORMS DEVELOPING AND
BECOMING MOST NUMEROUS ALONG AND SOUTH OF I-70. WILL CONTINUE WITH
HIGHEST POPS IN THESE AREAS...TAPERING OFF QUICKLY OVER NORTHERN
COUNTIES AS DRIER AIR FILTERS IN NORTH OF THE FRONT. LACK OF MORE
APPRECIABLE BL SHEAR AND UNIMPRESSIVE BOUNDARY LAYER FLOW SUPPORT
MORE OF A MULTICELLULAR MODE TO STORMS WITH PULSING INTENSITY. COULD
SEE STRONGER STORMS PRODUCE HAIL AND BRIEF WIND GUSTS BUT OVERALL
EXPECT STORMS TO REMAIN SUBSEVERE INTO THE EVENING.
TEMPS...CONSIDERING THE WARMER START THIS MORNING WHICH MOST OF THE
MODELS HAVE MISSED...AND THE POTENTIAL FOR SUN AND QUICK HEATING
THROUGH THE FIRST HALF OF THE DAY...TRENDED HIGH TEMPS TOWARDS
HRRR/4KM NAM WHICH PLACE MOST AREAS AT OR A COUPLE DEGREES WARMER
THAN MOS. EXPECT MID 70S NORTH TO LOWER 80S SOUTH.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
ISSUED AT 339 AM EDT TUE APR 26 2016
FORECAST CHALLENGES FOCUS ON PRECIP CHANCES THROUGH MUCH OF THE
PERIOD...AND POTENTIAL IMPACTS TO TEMPS AS LOCATION OF THE
OSCILLATING FRONTAL BOUNDARY WILL CREATE SHARP GRADIENTS FROM NORTH
TO SOUTH ACROSS THE FORECAST AREA AT TIMES.
CONVECTION LIKELY TO BE ONGOING AT 00Z THIS EVENING NEAR THE FRONTAL
BOUNDARY OVER THE SOUTHERN HALF OF THE FORECAST AREA. THE BOUNDARY
WILL CONTINUE TO PRESS INTO FAR SOUTHERN INDIANA LATE TONIGHT AIDED
BY BROAD HIGH PRESSURE OVER THE NORTHERN GREAT LAKES. ANY SCATTERED
CONVECTION WILL SHIFT TO THE LOWER WABASH VALLEY AND PERHAPS FAR
SOUTHERN ROW OF COUNTIES AFTER MIDNIGHT AS E/NE FLOW BRINGS DRIER
AIR BACK SOUTH INTO MUCH OF THE REGION. SHALLOW LAYER OF COOLER AIR
IN THE NEAR SURFACE LAYER WILL LEAD TO A SHARP INVERSION DEVELOPING
LATE TONIGHT AND CONTINUING INTO WEDNESDAY MORNING. THIS WILL LIKELY
MANIFEST AS A THICK LAYER OF STRATUS AND WILL CONTINUE WITH MOSTLY
CLOUDY SKIES ACROSS MUCH OF THE AREA.
FOCUS WILL SHIFT TO THE DEEP UPPER LOW AND ATTENDANT SURFACE WAVE
LIFTING NORTH THROUGH THE CENTRAL PLAINS WEDNESDAY MORNING. THIS
WILL PROMPT THE BOUNDARY TO LIFT BACK NORTH AS A WARM FRONT WHILE
THE LOW PRESSURE OCCLUDES OVER THE MISSOURI VALLEY. THESE FEATURES
WILL BE THE PRIMARY CATALYSTS IN THE POTENTIAL SIGNIFICANT SEVERE
WEATHER EXPECTED LATE TODAY AND TONIGHT OVER THE CENTRAL AND
SOUTHERN PLAINS. THAT ACTIVITY IS LIKELY TO COALESCE INTO A LINE OR
LINES OF WEAKER CONVECTION OVERNIGHT INTO WEDNESDAY MORNING AS IT
PRESSES EAST INTO THE MID MISSISSIPPI VALLEY AND LOWER OHIO VALLEY.
REMNANTS FROM THESE STORMS WILL GET DRAWN INTO THE REGION BY
WEDNESDAY AFTERNOON AS THE WARM FRONT LIFTS NORTH...AND MAY EVEN SEE
SOME RESTRENGTHENING OF STORMS LATE DAY IN THE LOWER WABASH VALLEY
WHERE ACTIVITY HAS BEST CHANCE TO BECOME SURFACE BASED IN THE WARM
SECTOR. NICE DIFFLUENCE ALOFT WILL HELP TO ENHANCE CONVECTIVE
COVERAGE WITH RAIN AND STORMS BECOMING WIDESPREAD FROM LATE
AFTERNOON INTO WEDNESDAY NIGHT. WILL CONTINUE WITH HIGH POPS ACROSS
THE FORECAST AREA AS A RESULT.
THE OCCLUDING SURFACE LOW WILL KICK OUT INTO THE REGION THURSDAY AS
THE UPPER LOW OPENS UP AND TRACKS INTO THE GREAT LAKES. DEEPER
MOISTURE AND BETTER FORCING SUPPORTS CARRYING BEST CHANCE POPS
ACROSS THE NORTHEAST HALF OF THE FORECAST AREA THURSDAY. SCATTERED
SHOWERS WILL GRADUALLY END THURSDAY EVENING AS THE LOW MOVES AWAY TO
THE EAST AND UPPER RIDGING QUICKLY EXPANDS INTO THE OHIO VALLEY.
TEMPS...WITH THE FRONT IN SOUTHERN COUNTIES WEDNESDAY...EXPECT A
FAIRLY SHARP TEMP GRADIENT FROM THE LOWER 60S IN THE NORTHEAST TO
THE MID 70S IN THE LOWER WABASH VALLEY. WARMER TEMPS EXPECTED
THURSDAY AND FAR SOUTHERN COUNTIES MAY MAKE A RUN AT 80 DEGREES WITH
MORE SUNSHINE AND ONLY WIDELY SCATTERED CONVECTION ANTICIPATED. AN
OVERALL MODEL BLEND CAPTURED THIS THINKING WELL. GENERALLY TRENDED
TOWARDS WARMER MAVMOS FOR LOWS THROUGH THE PERIOD.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
ISSUED AT 242 AM EDT TUE APR 26 2016
MODELS ARE CLOSE ENOUGH THAT THE SUPERBLEND INITIALIZATION WAS
ACCEPTED FOR MOST ITEMS.
AN UPPER LEVEL LOW INITIALLY OVER THE WESTERN HALF OF THE COUNTRY
WILL WORK SLOWLY EAST INTO THE REGION THROUGH THE LONG TERM. THIS
WILL ALSO BRING A SURFACE LOW PRESSURE SYSTEM WITH IT. THE RESULT OF
THIS SETUP WILL BE FREQUENT CHANCES FOR RAIN THROUGH THE LONG TERM.
GFS IS FASTER THAN ECMWF/CANADIAN IN BRINGING A RETURN OF RAIN
FRIDAY NIGHT. STUCK WITH THE CONSENSUS OF THE ECMWF/CANADIAN AND CUT
BACK SUPERBLEND/S POPS FRIDAY NIGHT. THIS IS CLOSE TO THE PREVIOUS
FORECAST AND THUS AVOIDS POTENTIAL FLIP-FLOPPING.
TEMPERATURES WILL START OUT NEAR AVERAGE...BUT WILL END UP COOLING
TO BELOW AVERAGE LATE IN THE PERIOD AS THE UPPER LOW MOVES IN.
&&
.AVIATION /DISCUSSION FOR 260600Z TAF ISSUANCE/...
ISSUED AT 1228 AM EDT TUE APR 26 2016
MODERATE CONFIDENCE THAT VFR CONDITIONS WILL DETERIORATE TO MVFR IN
THE 10Z-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 EXCEPT PERHAPS BRIEFLY AT THE ONSET AT LAF PER
RADAR TRENDS. THE ONCE WIDESPREAD HRRR REFLECTIVITY PROGS ARE NOW
EVEN HINTING AT SMALL COVERAGE AT BEST. THINK THE BETTER CHANCE FOR
CONVECTION WILL BE THIS AFTERNOON AS THE FRONTAL BOUNDARY WORKS ITS
WAY SOUTH ACROSS CENTRAL INDIANA. WOULD NOT RULE OUT MORE ACTIVITY
TONIGHT...BUT AGAIN COVERAGE LOOKS TOO LOW TO MENTION.
WINDS WILL BE SOUTHWEST 6 TO 10 KNOTS OVERNIGHT AND WEST AND
NORTHWEST LESS THAN 10 KNOTS IN THE WAKE OF THE FRONT AFTER DAYBREAK.
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 UNTIL
SHORTLY AFTER 00Z TONIGHT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....50
AVIATION...MK
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
242 AM EDT TUE APR 26 2016
.UPDATE...
THE LONG TERM 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 /REST OF TONIGHT/...
ISSUED AT 941 PM EDT MON APR 25 2016
UPDATE...
CURRENT TRENDS MATCH FORECAST...SO NO CHANGES. RAIN HAS STAYED OUT
OF CENTRAL INDIANA SO FAR...AND IS STILL NOT EXPECTED TO START
ENTERING THE NORTHERN COUNTIES UNTIL TUE 03Z. CURRENT RADAR MOSAIC
IS SHOWING A FEW ISOLATED SHOWERS AND THUNDERSTORMS JUST TO THE
WEST OF THE NORTHERN COUNTIES THAT COULD FILTER INTO THE AREA
AT THAT POINT. CURRENT TEMPS ACROSS THE AREA ARE GENERALLY IN THE
LOW 70S AND ARE PROJECTED TO BOTTOM OUT IN THE LOW 60S. UPDATED
GRIDS HAVE BEEN SENT.
PREVIOUS DISCUSSION...
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 /FRIDAY THROUGH MONDAY/...
ISSUED AT 242 AM EDT TUE APR 26 2016
MODELS ARE CLOSE ENOUGH THAT THE SUPERBLEND INITIALIZATION WAS
ACCEPTED FOR MOST ITEMS.
AN UPPER LEVEL LOW INITIALLY OVER THE WESTERN HALF OF THE COUNTRY
WILL WORK SLOWLY EAST INTO THE REGION THROUGH THE LONG TERM. THIS
WILL ALSO BRING A SURFACE LOW PRESSURE SYSTEM WITH IT. THE RESULT OF
THIS SETUP WILL BE FREQUENT CHANCES FOR RAIN THROUGH THE LONG TERM.
GFS IS FASTER THAN ECMWF/CANADIAN IN BRINGING A RETURN OF RAIN
FRIDAY NIGHT. STUCK WITH THE CONSENSUS OF THE ECMWF/CANADIAN AND CUT
BACK SUPERBLEND/S POPS FRIDAY NIGHT. THIS IS CLOSE TO THE PREVIOUS
FORECAST AND THUS AVOIDS POTENTIAL FLIP-FLOPPING.
TEMPERATURES WILL START OUT NEAR AVERAGE...BUT WILL END UP COOLING
TO BELOW AVERAGE LATE IN THE PERIOD AS THE UPPER LOW MOVES IN.
&&
.AVIATION /DISCUSSION FOR 260600Z TAF ISSUANCE/...
ISSUED AT 1228 AM EDT TUE APR 26 2016
MODERATE CONFIDENCE THAT VFR CONDITIONS WILL DETERIORATE TO MVFR IN
THE 10Z-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 EXCEPT PERHAPS BRIEFLY AT THE ONSET AT LAF PER
RADAR TRENDS. THE ONCE WIDESPREAD HRRR REFLECTIVITY PROGS ARE NOW
EVEN HINTING AT SMALL COVERAGE AT BEST. THINK THE BETTER CHANCE FOR
CONVECTION WILL BE THIS AFTERNOON AS THE FRONTAL BOUNDARY WORKS ITS
WAY SOUTH ACROSS CENTRAL INDIANA. WOULD NOT RULE OUT MORE ACTIVITY
TONIGHT...BUT AGAIN COVERAGE LOOKS TOO LOW TO MENTION.
WINDS WILL BE SOUTHWEST 6 TO 10 KNOTS OVERNIGHT AND WEST AND
NORTHWEST LESS THAN 10 KNOTS IN THE WAKE OF THE FRONT AFTER DAYBREAK.
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 UNTIL
SHORTLY AFTER 00Z TONIGHT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...PUMA
NEAR TERM...PUMA/TDUD
SHORT TERM...PUMA
LONG TERM....50
AVIATION...MK
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
235 AM EDT TUE APR 26 2016
.SYNOPSIS...
ISSUED AT 230 AM EDT TUE APR 26 2016
INCREASING SOUTHWESTERLY WINDS WILL HELP DRAW IN WARMER AND
INCREASINGLY HUMID AIR TO HELP SET THE STAGE FOR SHOWERS AND
THUNDERSTORMS AHEAD OF A COLD FRONT. 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
TODAY... 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 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 226 AM EDT TUE APR 26 2016
A COLD FRONT WAS MOVING SOUTH ACROSS LOWER MICH AND LAKE MICHIGAN
AND WILL MOVE ACROSS THE AREA LATE TONIGHT AND EARLY WEDNESDAY.
SHOWERS AND STORMS ARE POSSIBLE AHEAD OF THE FRONT...BUT SHOULD
END BEFORE DAYBREAK. OTHERWISE...SOME LOW CLOUDS SHOULD SPREAD
INTO NW INDIANA AND THE SBN TERMINAL AS THE COMBINATION OF THE
COLDER AIR BEHIND THE FRONT AND THE COLD MARINE LAYER ACCENTUATE
THE FRONT. ADDED IFR CONDITIONS AT SOUTH BEND DURING THE MORNING
FOR THESE CLOUDS. OTHERWISE...WINDS SHOULD VEER TO THE NORTHEAST
AS A LARGE SURFACE HIGH MOVES INTO THE REGION.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...FISHER/SKIPPER
SHORT TERM...FISHER
LONG TERM...AGD
AVIATION...SKIPPER
VISIT US AT WWW.WEATHER.GOV/IWX
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1228 AM EDT TUE APR 26 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 /REST OF TONIGHT/...
ISSUED AT 941 PM EDT MON APR 25 2016
UPDATE...
CURRENT TRENDS MATCH FORECAST...SO NO CHANGES. RAIN HAS STAYED OUT
OF CENTRAL INDIANA SO FAR...AND IS STILL NOT EXPECTED TO START
ENTERING THE NORTHERN COUNTIES UNTIL TUE 03Z. CURRENT RADAR MOSAIC
IS SHOWING A FEW ISOLATED SHOWERS AND THUNDERSTORMS JUST TO THE
WEST OF THE NORTHERN COUNTIES THAT COULD FILTER INTO THE AREA
AT THAT POINT. CURRENT TEMPS ACROSS THE AREA ARE GENERALLY IN THE
LOW 70S AND ARE PROJECTED TO BOTTOM OUT IN THE LOW 60S. UPDATED
GRIDS HAVE BEEN SENT.
PREVIOUS DISCUSSION...
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 260600Z TAF ISSUANCE/...
ISSUED AT 1228 AM EDT TUE APR 26 2016
MODERATE CONFIDENCE THAT VFR CONDITIONS WILL DETERIORATE TO MVFR IN
THE 10Z-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 EXCEPT PERHAPS BRIEFLY AT THE ONSET AT LAF PER
RADAR TRENDS. THE ONCE WIDESPREAD HRRR REFLECTIVITY PROGS ARE NOW
EVEN HINTING AT SMALL COVERAGE AT BEST. THINK THE BETTER CHANCE FOR
CONVECTION WILL BE THIS AFTERNOON AS THE FRONTAL BOUNDARY WORKS ITS
WAY SOUTH ACROSS CENTRAL INDIANA. WOULD NOT RULE OUT MORE ACTIVITY
TONIGHT...BUT AGAIN COVERAGE LOOKS TOO LOW TO MENTION.
WINDS WILL BE SOUTHWEST 6 TO 10 KNOTS OVERNIGHT AND WEST AND
NORTHWEST LESS THAN 10 KNOTS IN THE WAKE OF THE FRONT AFTER DAYBREAK.
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 UNTIL
SHORTLY AFTER 00Z TONIGHT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...PUMA
NEAR TERM...PUMA/TDUD
SHORT TERM...PUMA
LONG TERM....JH
AVIATION...MK
AREA FORECAST DISCUSSION
NWS JACKSON KY
124 AM EDT TUE APR 26 2016
.UPDATE...
ISSUED AT 1256 AM EDT TUE APR 26 2016
OVERALL NO BIG ISSUES FOR THE OVERNIGHT HOURS WEATHER WISE. WE ARE
DEALING WITH SOME TEMP SPLITS...AND ADJUSTED TEMPS TO BETTER MATCH
THE TRENDS. A FEW PASSING MID CLOUDS TONIGHT...BUT MOST LOCATIONS
SEEING CLEAR TO MOSTLY CLEAR SKIES. THEREFORE UPDATE WAS MINOR AT
THIS POINT.
UPDATE ISSUED AT 1014 PM EDT MON APR 25 2016
CLOUDS ARE SCARCE OVERALL...AND HAVE BACKED OFF ON SKY COVER FOR A
WHILE LONGER TONIGHT. OTHERWISE...THE BLENDING OF OBS INTO THE
FORECAST RESULTED IN LITTLE CHANGE.
UPDATE ISSUED AT 717 PM EDT MON APR 25 2016
THE UPDATE MAINLY BLENDS LATE DAY OBS INTO THE NIGHT TIME
FORECAST...WITH NO SIGNIFICANT CHANGES.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 243 PM EDT MON APR 25 2016
HIGH PRESSURE RIDGE AXIS HAS CONTINUED TO SHIFT EAST TODAY...WITH
MODEST RETURN FLOW SETTING UP ACROSS KENTUCKY WITH AT TIMES GUSTY
SOUTHWEST WINDS. DAYTIME MIXING HAS BROUGHT DEWPOINTS BACK DOWN
INTO THE MID TO UPPER 40S IN MANY AREAS...A GOOD 5 TO 10 DEGREES
UNDER WHAT MODELS HAD BEEN ADVERTISING YESTERDAY. WITH THIS DRIER
AIR...ANY TERRAIN INDUCED CONVECTION HAS BEEN KEPT AT
BAY...LEADING TO A DRY AFTERNOON ACROSS EASTERN KENTUCKY. AS
INSTABILITY DROPS OFF THIS EVENING...CU SHOULD DISSIPATE QUITE A
BIT...LEADING TO A RATHER PLEASANT EVENING AS TEMPERATURES QUICKLY
COOL OFF UNDER THE MOSTLY CLEAR SKIES...ESPECIALLY IN THE VALLEYS.
THIS WILL SET UP A RIDGE/VALLEY SPLIT TONIGHT WITH SHELTERED VALLEYS
FALLING BACK INTO THE MID 50S...WHILE THE MIXED RIDGES STAY IN THE
LOWER 60S.
TOMORROW...A SHORTWAVE PUSHING INTO NEW ENGLAND...WILL SEND A
SURFACE BOUNDARY SOUTH ACROSS SOUTHERN OHIO. WHILE MOISTURE WILL
CONTINUE TO SLOWLY INCREASE AHEAD OF THIS BOUNDARY...FEEL THAT
MODELS MAY STILL BE OVERDOING SURFACE MOISTURE AND ALLOWING FOR
WAY TOO MUCH CONVECTION. UNTIL SOMETHING CAN FORM ALONG THE
BOUNDARY...WHICH LIKELY WON`T HAPPEN UNTIL LATE AFTERNOON AS AN
APPROACHING VORT MAX CROSSES THE REGION...WE`LL BE HARD PRESSED
TO SEE MUCH CONVECTION AS WE WILL BE LACKING TRIGGERS. ALSO...THE
IMPRESSIVE INSTABILITY ON THE MODELS MAY BE A BIT OVERDONE AS
WELL...SO THAT LENDS ITSELF TO LESS CONVECTION AS WELL. BY LATE IN
THE DAY (AFTER 21Z)...THE THREAT FOR SHOWERS AND STORMS MOVING IN
FROM THE NORTH SHOULD INCREASE AS ACTIVITY FIRES ALONG THE SURFACE
BOUNDARY AND DRIFTS SOUTH AND EAST. STORM MOVEMENT SHOULD BE MORE
TO THE EAST WITH THE STEERING FLOW...SO STILL SOME QUESTION HOW
FAR SOUTH CONVECTION WILL REACH AND WILL BE MAINLY DETERMINED BY
OUTFLOW BOUNDARIES...PUSHING CONVECTION SOUTHWARD. THUS...HARD TO
GO ABOVE CHANCE POPS THROUGH THE EVENING AS THERE REMAINS TOO MUCH
UNCERTAINTY ON RAIN CHANCES. ALSO...WHILE WE ARE IN A MARGINAL
AREA FOR SEVERE STORMS TOMORROW...OVERALL SHEAR IS VERY
UNIMPRESSIVE. IF THE INSTABILITY IS ALSO LESS IMPRESSIVE LIKE I
ANTICIPATE...THAN THE SEVERE STORM CHANCES WILL BE MINIMAL.
HOWEVER...SOME SMALL HAIL COULD STILL BE SEEN BY THE STRONGEST
STORMS.
AS THE VORT MAX AND INSTABILITY EXITS BY LATE TUESDAY
EVENING...WE`LL HAVE SHORTWAVE RIDGING BUILDING IN FOR THE SECOND
HALF OF THE NIGHT...WHICH WOULD LEND ITSELF TO BEING MUCH QUIETER
THROUGH MUCH OF THE NIGHT. HOWEVER...GIVEN THE PROXIMITY OF THE
SURFACE BOUNDARY AND ANY OUTFLOW BOUNDARIES OVER THE AREA...WILL
MAINTAIN SOME ISOLATED SHOWERS/STORMS THROUGH THE NIGHT. GIVEN THE
INCREASED CLOUD COVER...TEMPERATURES WILL BE FAIRLY MILD...ONLY
FALLING A TOUCH UNDER 60 FOR MOST AREAS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 359 PM EDT MON APR 25 2016
AN ACTIVE PATTERN WILL BE IN STORE THROUGH THE PERIOD. AN UPPER
LEVEL LOW WILL GRADUALLY LIFT NORTHEAST OUT OF THE PLAINS AND
EVENTUALLY GET ABSORBED INTO THE CYCLONIC FLOW ASSOCIATED WITH A
DEEP EASTERN CANADIAN SYSTEM THROUGH THE END OF THE WORK
WEEK. SHORT WAVE ENERGY...ALONG WITH A LINGERING SURFACE FRONT
WILL BRING BOUTS OF UNSETTLED WEATHER TO THE OHIO AND TENNESSEE
VALLEYS THROUGH THURSDAY NIGHT. RIDGING WILL THEN MOVE IN ACROSS
THE MISSISSIPPI VALLEY ON FRIDAY...PROVIDING SOME TEMPORARY DRY
WEATHER. MEANWHILE...ANOTHER TROUGH WILL BE TAKING SHAPE ACROSS
THE WESTERN CONUS...WITH PIECES OF ENERGY EJECTING EASTWARD INTO
THE MISSISSIPPI VALLEY AND ALLOWING A RETURN OF UNSETTLED WEATHER
TO THE REGION SATURDAY THROUGH MONDAY.
WEDNESDAY THROUGH THURSDAY NIGHT WILL FEATURE SCATTERED TO
NUMEROUS SHOWERS AND STORMS ACROSS EASTERN KENTUCKY. HAVE ALLOWED
FOR SOMEWHAT OF A DIURNAL INFLUENCE TO THE POPS TO MITIGATE SOME
OF THE LOWER CONFIDENCE IN TIMING INDIVIDUAL FORCING MECHANISMS.
FRIDAY AND FRIDAY NIGHT LOOK DRY AS SHORT WAVE RIDGING MOVES IN.
THERE IS DISAGREEMENT ON HOW QUICKLY FORCING AND MOISTURE RETURN
FROM THE WEST ON SATURDAY. HAVE UNDERCUT THE POPS A TAD...BUT HAVE
STILL ALLOWED FOR A CHANCE OF SHOWERS IN THE AFTERNOON. THE
OVERALL BEST CHANCE OF POPS WILL COME IN ON SUNDAY...WITH
LINGERING CHANCES POSSIBLE INTO MONDAY...WITH TROUGHINESS
REMAINING ACROSS THE OHIO VALLEY.
TEMPERATURES WILL AVERAGE ABOVE NORMAL THROUGH THE WEEKEND...WITH
HIGHS AVERAGING IN THE UPPER 70S TO AROUND 80 AND LOWS IN THE 50S.
READINGS WILL DROP BACK CLOSER TO SEASONAL NORMALS BY EARLY NEXT
WEEK...AS HIGHS RETREAT TO THE LOWER 70S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 124 AM EDT TUE APR 26 2016
VFR REMAINS THE STORY FOR THE TAF PERIOD. A FRONT WILL SAG SOUTH
FOR TUESDAY AND THIS WILL AID IN CU DEVELOPMENT THROUGH THE
AFTERNOON. THEN STORMS POSSIBLE BY TUESDAY LATE
AFTERNOON/EVENING. RIGHT NOW WILL GO WITH VCTS IN THE TAF SITES
TOWARD LATE AFTERNOON/EVENING...BUT OVERALL BEST CHANCE WOULD BE
NEAR THE I64 CORRIDOR/NORTHERN TAF SITES UNTIL LATE IN THE TAF
PERIOD. SOME STORMS COULD BE STRONG WITH GUSTY WINDS AND
HAIL...OVERALL WINDS DO INCREASE IN THE AFTERNOON WITH SOME GUSTS
IN THE 15 KT RANGE.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...KAS
LONG TERM...GEOGERIAN
AVIATION...DJ
Area Forecast Discussion
National Weather Service Louisville KY
118 AM EDT TUE APR 26 2016
...Updated Aviation Discussion...
...Forecast Update...
Issued at 922 PM EDT Mon Apr 25 2016
Overall, no major changes to the forecast for the remainder of this
evening and overnight. Continue to expect a dry overnight with a
weak impulse traveling across central IL/IN to keep bulk of
showers/storms north of the area. This feature will act to drop a
frontal boundary toward the area, which may bring a few light
showers toward dawn but most likely just an increase in cloud cover.
Mild night with lows holding up in the 60s.
For tomorrow, latest guidance continues to suggest the combination
of a passing mid-level wave and daytime instability will spark a
round of showers and storms by mid-afternoon. Consensus of the hi-
res data shows this to initiate across southern Indiana, then track
into north central or central Kentucky. In coordination with
neighboring offices, bumped up chances into the 50 to 70 percent
range for parts of the area for mid/late afternoon into early
evening. Severe threat still is on the table with some loosely
organized multi-cell clusters producing damaging winds.
.SHORT TERM (Now through Tuesday Night)...
Issued at 309 PM EDT Mon Apr 25 2016
Now - Tonight...
Dry weather will continue this afternoon and through the much
overnight under influence of high pressure. For the remainder of the
afternoon, highs will max out in the 80 to 85 range with scattered
diurnally driven clouds. SW winds between 10 and 15 mph will gust up
around 25 to 30 mph at times.
Expect lows in the lower 60s tonight with increasing cloud cover
toward dawn. A few rain showers may be possible toward sunrise but
most spots should remain dry.
...Rounds of Showers and Storms through Midweek, Some Strong
Possible...
Tuesday - Wednesday Night...
By Tuesday, surface low will travel into New England with a trailing
cold front stretching across southern IL/IN/OH toward the Ohio
River. With destabilization in the form of low level moisture
convergence and heating ahead of the front, expect scattered showers
and storms to develop by mid to late afternoon. Additionally, a
subtle mid level perturbation will slide through the flow aloft,
helping to enhance deep shear a bit during this time. This could
promote some storm organization in the form of a few line segments
with a damaging wind threat. Heavy rain, lightning and some hail
will also be secondary threats. Highs should reach into the low 80s
on Tuesday.
Think we`ll see a drop off in coverage on Tuesday Night with the
passage of the wave and loss of heating. However, with the front
still in the area will keep lower coverage in the grids. Expect mild
lows in the low 60s.
Strong and negatively tilted shortwave ejects out of the Plains to
the upper Midwest during the day Wednesday through Wednesday night.
As this occurs, low level response will help to drag the stalled
frontal boundary back to the north as a warm front. This will allow
for scattered to numerous showers and storms along the warm front in
the morning. Then, another round of showers and storms is expected
once the better forcing arrives in the afternoon and evening.
Destabilization will be in question, but should be able to at least
realize some instability in the warm sector by afternoon/evening.
This combined with the forcing and enough deep layer shear for
organization a few strong storms will again be possible. Main
threats for severe would be damaging winds. Additionally, heavy
rainfall, cloud to ground lightning, and some hail will also be
possible with any stronger storm.
Coverage of storms should be diminishing by dawn on Thursday with
temperatures falling into the low 60s by this time.
.LONG TERM (Wednesday through Monday)...
Issued at 355 PM EDT Mon Apr 24 2016
The active, progressive upper level flow with periodic impulses
moving through the lower Ohio Valley will continue late in the work
week, this weekend and into early next week. Overall, an unsettled
pattern for the area.
On Thursday, one round of showers and thunderstorms will likely be
exiting during the early morning hours as a PV anomaly passes
through the region. The surface low remains back to our northwest,
so with daytime heating and modest lapse rates, MUCAPE around 1000
J/kg develops during the afternoon. Shear profiles aren`t
impressive, so storm mode likely to be pulse or loosely organized
multicells. Likely some residual boundaries around so scattered
afternoon and early evening showers/storms will be possible. Look
for highs right around 80.
Friday continues to look like our driest day of the week as we`re in
between weather systems. High pressure originating out of the lower
Great Lakes will provide drier, slightly cooler air. Look for partly
to mostly sunny skies and highs in the low 70s to near 80, warmest
near the TN border.
The western trough will reload and eject another surface low out
into the central Plains and mid-Mississippi valley this weekend.
Still plenty of uncertainty in the strength and position of the
surface low and warm front Saturday morning, but overall the chances
of showers/storms will be on the increase during the day. Higher
confidence that we`ll see additional rounds of storms Saturday night
into Sunday, and likely into the first part of next week. The
environment will favor stronger to potentially severe storms as well
with a more favorable shear environment. Latest 7 day rainfall
outlook shows the potential for 2 to 4 inches of rain through early
next week so depending on how storms play this week, we may have to
monitor the hydrologic side of things more closely.
&&
.AVIATION (06Z TAF Update)...
Updated at 115 AM EDT Tue Apr 26 2016
Will be watching upstream convection for potential for showers
around the SDF/LEX terminals this morning, otherwise expecting VFR
conditions with south to southwest winds the first half of the
period. Hi-res guidance continues to struggle with timing of
afternoon storms, but it does appear some upper level energy will
cross to our north and provide focus for some storms to develop in
the late afternoon into evening hours. Brief IFR conditions are
possible as well as gusty winds with these storms. Any storms should
be dissipating by the end of the period, but a frontal boundary will
stall over the region and should provide a focus for additional
showers/storms the next few days.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Update.........ZT
Short Term.....BJS
Long Term......ZT
Aviation.......RJS
Area Forecast Discussion
National Weather Service Paducah KY
1205 AM CDT TUE APR 26 2016
.UPDATE...
Issued at 835 PM CDT Mon Apr 25 2016
Convective trends this evening appear to matching closer to the
GFS, Canadian, NAM-WRF (NMM & ARW versions), and the HRRR guidance
for tonight through Tuesday night. Current convection over
Central/Southwest Illinois poised along low level convergence
smack in the middle of a SSW-NNE oriented theta-e plume. As the
night progresses, this theta-e axis should become more oriented
west to east, pulling richer moisture toward Southwest
Indiana/Southeast Illinois/Northwest Kentucky between 3 am and 7
am CDT. This could produce isolated shower and thunderstorm
activity in that area. Noticed even SPC has modified their
convective outlook northwest of the WFO PAH CWA reflecting a
greater severe potential along the I-70 corridor over MO/IL for
the rest of tonight.
The adjustment this evening for Tuesday will be an increase in
coverage of showers and thunderstorms during the middle and late
afternoon hours, a lesser coverage (especially along the AR/TN
borders) Tuesday evening, then a ramp up of PoPs/Weather late
Tuesday night. Numerical guidance has been hinting at the
propagation of an MCS southeast across the area late Tuesday
night.
Other sensible weather elements, such as sky, temperatures,
dewpoints, and winds appear to be in line. Was not surprise by the
expansion of the SPC Day 2 Marginal risk area over the area for
Tuesday. Cannot rule a stray storm producing severe or near severe
hail or wind.
&&
.SHORT TERM...(Tonight through Wednesday night)
Issued at 237 PM CDT Mon Apr 25 2016
Models are in pretty decent agreement on the track of our
upcoming weather system. Models show a surface low over eastern
Colorado at 12z Tuesday, moving over southeast Nebraska by 00z
Thursday. The warm front associated with this low will be hanging
out north of the PAH forecast area at 12z Tuesday, dropping south
into our region by Tuesday evening and remaining in our area
through Wednesday. The surface low will then bring the trailing
cold front across our area Wednesday night.
Showers and thunderstorms can be expected to develop along the
warm front Tuesday into Tuesday night, and along and ahead of the
cold front Wednesday into Wednesday night. ECMWF and GFS are in
good agreement showing scattered showers and thunderstorms Tuesday
into Tuesday evening, with the best chances in our northern
counties along the warm front. Models then show a push of moisture
into our western counties late Tuesday night, spreading east
through the day Wednesday, continuing into Wednesday night. Went
with increasing chances from north to south late tonight into
Tuesday, the went with likely pops north to good chance south
Tuesday night. Went with likely pops area wide on Wednesday, with
chances gradually decreasing from the west Wednesday night.
SPC has included all but our southern Kentucky counties in a
marginal risk for severe storms Tuesday into possibly Tuesday
evening due to some pretty impressive instability along and south
of the warm front. For Wednesday into Wednesday evening, our
western two thirds of counties are in a slight risk and the rest
of our area in a marginal as the approaching cold front moves into
our already unstable air mass. As for rainfall amounts, our
overall totals should be highest across our northern counties
where the warm front will trigger some heavier rainfall Tuesday
into Tuesday night, but isolated higher amounts will be possible
area wide Wednesday into Wednesday evening with thunderstorm
activity.
Our southerly winds will bring not only plenty of moisture into
the region for the next couple of days, but continued very warm
conditions. Temperatures will remain unseasonably warm through
Wednesday night. Low temperatures tonight through Wednesday night
will mostly be in the lower to middle 60s. Highs Tuesday will be
in the 80 to 85 degree range, then the additional cloud
cover/precipitation on Wednesday will drop readings back several
degrees into the middle to upper 70s.
.LONG TERM...(Thursday through Monday)
Issued at 237 PM CDT Mon Apr 25 2016
Average confidence in the long term due to multiple rain events and
some model disparity where timing, track, and coverage are concerned
with these events.
On Thursday small precipitation chances exist over the northeast
third/half of the CWA on the back side of a system that crosses the
region Wednesday night. The frontal boundary associated with this
system is forecast to become stationary just to our south Thursday
night and right now that period looks dry.
A closed H5 low moving northeast out of the four corners region on
Friday will induce a surface low on the aforementioned boundary over
the panhandle of Texas which will begin to generate an overrunning
rain event that is forecast to develop showers and thunderstorms
into our far western counties on Friday. Models not seeing eye to
eye too well with the onset of precipitation so it may not begin as
early as originally thought.
As the system slowly approaches, precipitation chances continue to
ramp up Friday into Friday night, with the highest chances area wide
being Saturday and Saturday night with the passage of the system. In
its wake, precipitation chances are expected to taper off from the
west but will linger from Sunday into Monday due to the presence of
upstream upper level energy and decent moisture.
Temperatures remain at or above normal through the period.
&&
.AVIATION...
Issued at 1204 am CDT Tue Apr 26 2016
Challenging TAFs continue with the 06z Tuesday issuance. Kept with
MVFR ceilings with the KCGI TAF, with sharp ceiling changes at
KEVV and KOWB, especially during the last 6-9 hours of the TAF
period as convective elements work along surface boundary. Most
variation in weather conditions will likely range between 14z
Tuesday to 03z Wednesday.
&&
.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
UPDATE...Smith
SHORT TERM...RST
LONG TERM...JP
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
410 AM EDT TUE APR 26 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 401 AM EDT TUE APR 26 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW SHRTWV MOVING THRU
THE UPR GREAT LKS EARLY THIS MRNG. BUT SINCE THIS DISTURBANCE IS
ENTERING CONFLUENT ZN BTWN NW FLOW OVER ONTARIO ARND CLOSED UPR LO
OVER THE CNDN MARITIMES AND WLY SRN BRANCH FLOW OVER THE CONUS...
THIS DISTURBANCE IS WEAKENING AS HINTED BY WARMING CLD TOP TEMPS
OVER THE CWA. MOST OF THE LINGERING PCPN IN THE FORM OF RA/SN IS OVER
THE E HALF CLOSER TO THE EXITING/WEAKENING DISTURBANCE...BUT
LINGERING LLVL MSTR UNDER THE MID LVL DRYING/SUBSIDENCE IN ITS WAKE
IS ALLOWING SOME LIGHT DRIZZLE/FLURRIES TO LINGER FARTHER W...
ESPECIALLY WHERE LLVL GUSTY NE FLOW IS UPSLOPING. BUT MUCH DRIER LLVL
AIR IS JUST TO THE N ASSOCIATED WITH HI PRES BLDG INTO NRN ONTARIO.
THE 00Z YPL RAOB IS QUITE DRY IN THE LLVLS...WITH H925/H85 DEWPT
DEPRESSIONS 17C/11C. STLT IMAGERY SHOWS THE NRN EDGE OF THE CLDS ARE
MOVING STEADILY TO THE S ACRS LK SUP WITH THIS DRY ADVECTION IN THE
LLVL NE FLOW. THIS CLRG LINE IS APRCHG THE KEWEENAW AT FCST ISSUANCE.
LOOKING TO THE W...THERE IS ANOTHER WEAKER SRN BRANCH SHRTWV SLIDING
E THRU CENTRAL MN.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON LLVL DRYING TRENDS/
IMPACT ON LINGERING LGT PCPN THIS MRNG AND THEN MIN TEMPS TNGT AS
DRIER/CHILLY AIRMASS ASSOCIATED WITH ONTARIO HI PRES WL DOMINATE.
TODAY...ALTHOUGH THERE ARE SOME DIFFERENCES ON THE TIMING...SHORTER
TERM MODELS ALL SHOW STEADY LLVL DRYING TODAY IN CONTINUED STEADY/
SLOWLY WEAKENING NE FLOW ON THE SRN FLANK OF ONTARIO HI PRES. GIVEN
THE STLT CLD TRENDS/FALLING SFC DEWPTS JUST TO THE N...PREFER THE
MODELS THAT SHOW MORE AGGRESSIVE LLVL DRYING. SO EXPECT LINGERING
DRIZZLE/FREEZING DRIZZLE/FLURRIES TO DIMINISH AND END BY ABOUT
12Z...LAST IN THE UPSLOPE HIER TERRAIN AREAS OF THE NCNTRL. SOME LO
CLDS MAY LINGER A BIT LONGER...BUT EVEN THESE SHOULD DISSOLVE N-S BY
LATE MRNG. ALTHOUGH SHRTWV IN MN IS FCST TO SLIDE E AND BRING SOME
DPVA/DEEP LYR QVECTOR CNVGC MAINLY TO THE WI BORDER AREAS...INFLUX OF
LLVL DRY AIR WL PREVENT ANY PCPN AND LIMIT IMPACT TO JUST MORE MID/HI
CLDS. DESPITE THE RETURN OF SOME SUNSHINE ESPECIALLY OVER THE NRN
TIER...NE FLOW OFF THE CHILLY LK SUP WATERS WL LIMIT DIURNAL TEMP
RECOVERY TO NO HIER THAN ABOUT 40 NEAR THE LK. TEMPS WL TOP OUT ARND
50 OVER THE SCENTRAL.
TNGT...ANY LINGERING CLDS ASSOCIATED WITH THE SECOND SHRTWV WL CLR
THE FAR SCENTRAL BY 00Z THIS EVNG...SETTING THE STAGE FOR A CHILLY
NGT AS THE SFC HI PRES IN ONTARIO EXTENDS A SFC RDG AXIS INTO THE
UPR LKS UNDER LARGE SCALE SUBSIDENCE. THE ONLY LIMITING FACTOR WL BE
A PERSISTENT LIGHT NE FLOW TO THE S OF THE HI CENTER LINGERING OVER
ONTARIO. BUT WITH PWAT FALLING AOB 0.25 INCH...WL TEND TOWARD THE LO
END OF GUIDANCE FOR THE INTERIOR SHELTERED LOCATIONS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 409 AM EDT TUE APR 26 2016
SPLIT FLOW ACROSS NORTH AMERICA. SHARP TROUGH IN THE NORTHERN POLAR
JET STREAM PERSISTS OVER EASTERN CANADA MOST OF THE WEEK. STRONG
TROUGH IN THE SOUTHERN STREAM PUSHING ACROSS THE WESTERN CONUS ATTM
SHEARS OUT WED INTO THU AS IT PUSHES INTO CONFLUENT FLOW ON WESTERN
EDGE OF THE EASTERN CANADA UPPER TROUGH. ANOTHER TROUGH MOVES ACROSS
WESTERN CONUS FRIDAY AND AS THAT SYSTEM LIFTS TOWARD GREAT LAKES LATE
IN THE WEEKEND COULD SEE SOME LIGHT PRECIPITATION. APPEARS COOLER
AND UNSETTLED WEATHER MAY LINGER EARLY NEXT WEEK AS THIS UPPER LOW
MEANDERS OVER THE GREAT LAKES. LATEST CPC FORECAST THEN SHOWS
GREATER CHANCES FOR ABOVE NORMAL TEMPS AND BELOW NORMAL PRECIP SETS
UP FOR MAY 3RD THROUGH MAY 8TH.
AS IT HAS LOOKED LIKE FOR A WHILE...MAIN SFC FEATURE THIS WEEK WILL
BE HIGH PRESSURE VCNTY OF HUDSON BAY WITH RIDGING EXTENDING OVER THE
UPPER GREAT LAKES. AS THE SHORTWAVE TROUGH CURRENTLY MOVING ACROSS
THE ROCKIES TO THE PLAINS TODAY LIFTS TOWARD UPPER GREAT LAKES WED
NIGHT INTO THU...SHOULD SEE INCREASING MID CLOUDS...ESPECIALLY OVER
SOUTH HALF OF CWA. WEAKENING FORCING ALONG WITH SOUNDINGS SHOWING
DRY AIR WITH THE HIGH BLO 700MB INDICATES MINIMAL CHANCES OF RAIN
OVER SOUTH CENTRAL ON THU. WEAKENING SYSTEM DEPARTS THU NIGHT THEN
COULD SEE INCREASING MID CLOUDS AGAIN FRI AS ANOTHER SYSTEM SHEARS
OUT WHILE MOVING FM THE CENTRAL PLAINS TOWARD THE STRONG LOW-LEVEL
RIDGE. GRADUALLY WARMING H85 TEMPS SHOULD ALLOW TEMPS INLAND TO
SLOWLY WARM THROUGH THE 50S TO POSSIBLY LOWER 60S BY FRI OR SAT.
GRADIENT NORTHEAST WINDS OUT OF THE HIGH WILL KEEP LK SUPERIOR SHORE
MAINLY IN THE 40S. WITH THE HIGH AND DRY AIRMASS IN VCNTY CONTINUE
TO PREFER NIGHTTIME TEMPS AT OR BLO FREEZING INLAND FOR THE REST OF
THE WEEK. DRY AIR SHOULD ALSO LEAD TO LOW TD/RH IN THE AFTN. WINDS
FOR MOST PART LOOK LIGHT SO EVEN THOUGH FIRE WEATHER CONCERNS WILL
BE INCREASING...THEY SHOULD BE KEPT IN CHECK.
CONSENSUS CONTINUES TO SHOW SLIGHT CHANCE POPS LATER IN THE WEEKEND
AS YET ANOTHER UPPER TROUGH MOVES TOWARD GREAT LAKES. PREVIOUS ECMWF
WAS SHOWING SYSTEM BEGINNING TO AFFECT AREA AS EARLY AS SAT NIGHT
BUT 00Z RUN DELAYS THE WEAKENING SYSTEM UNTIL LATE SUN INTO SUN
NIGHT/MON. GFS AND GEM-NH ARE SHUNTED MORE TO THE SOUTH...WHICH
MAKES SENSE GIVEN THE STRONG DRY HIGH PRESSURE PERSISTING. OVERALL
NOT LOOKING LIKE MUCH OF A CHANCE FOR RAIN FOR THE EXTENDED PERIOD
UNTIL EARLY NEXT WEEK...MAYBE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 124 AM EDT TUE APR 26 2016
AS WEAK LOW SLIDES SE OF THE REGION OVERNIGHT...PCPN WILL BE
TAPERING OFF FM W TO E AND RAIN WILL MIX WITH OR CHANGE OVER TO SNOW
AT KCMX AND KSAW. WITH SHALLOW MOIST EASTERLY FLOW
CONTINUING...EXPECT IFR/LIFR CONDITIONS TO PERSIST AT KIWD/KCMX/KSAW
OVERNIGHT. 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 401 AM EDT TUE APR 26 2016
ENE WINDS UP TO 25-30 KTS OVER THE LAKE THIS MORNING...STRONGEST
OVER THE W...WILL DIMINISH THROUGH THE DAY TO UNDER 20 KTS AS A HI
PRES RIDGE BUILDS S THRU ONTARIO AND THE PRES GRADIENT WEAKENS. E TO
NE WINDS GENERALLY UNDER 20-25KT WILL THEN PREVAIL THRU SAT TO THE S
OF PERSISTENT HI PRES NEAR HUDSON BAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...VOSS
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
402 AM EDT TUE APR 26 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 401 AM EDT TUE APR 26 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW SHRTWV MOVING THRU
THE UPR GREAT LKS EARLY THIS MRNG. BUT SINCE THIS DISTURBANCE IS
ENTERING CONFLUENT ZN BTWN NW FLOW OVER ONTARIO ARND CLOSED UPR LO
OVER THE CNDN MARITIMES AND WLY SRN BRANCH FLOW OVER THE CONUS...
THIS DISTURBANCE IS WEAKENING AS HINTED BY WARMING CLD TOP TEMPS
OVER THE CWA. MOST OF THE LINGERING PCPN IN THE FORM OF RA/SN IS OVER
THE E HALF CLOSER TO THE EXITING/WEAKENING DISTURBANCE...BUT
LINGERING LLVL MSTR UNDER THE MID LVL DRYING/SUBSIDENCE IN ITS WAKE
IS ALLOWING SOME LIGHT DRIZZLE/FLURRIES TO LINGER FARTHER W...
ESPECIALLY WHERE LLVL GUSTY NE FLOW IS UPSLOPING. BUT MUCH DRIER LLVL
AIR IS JUST TO THE N ASSOCIATED WITH HI PRES BLDG INTO NRN ONTARIO.
THE 00Z YPL RAOB IS QUITE DRY IN THE LLVLS...WITH H925/H85 DEWPT
DEPRESSIONS 17C/11C. STLT IMAGERY SHOWS THE NRN EDGE OF THE CLDS ARE
MOVING STEADILY TO THE S ACRS LK SUP WITH THIS DRY ADVECTION IN THE
LLVL NE FLOW. THIS CLRG LINE IS APRCHG THE KEWEENAW AT FCST ISSUANCE.
LOOKING TO THE W...THERE IS ANOTHER WEAKER SRN BRANCH SHRTWV SLIDING
E THRU CENTRAL MN.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON LLVL DRYING TRENDS/
IMPACT ON LINGERING LGT PCPN THIS MRNG AND THEN MIN TEMPS TNGT AS
DRIER/CHILLY AIRMASS ASSOCIATED WITH ONTARIO HI PRES WL DOMINATE.
TODAY...ALTHOUGH THERE ARE SOME DIFFERENCES ON THE TIMING...SHORTER
TERM MODELS ALL SHOW STEADY LLVL DRYING TODAY IN CONTINUED STEADY/
SLOWLY WEAKENING NE FLOW ON THE SRN FLANK OF ONTARIO HI PRES. GIVEN
THE STLT CLD TRENDS/FALLING SFC DEWPTS JUST TO THE N...PREFER THE
MODELS THAT SHOW MORE AGGRESSIVE LLVL DRYING. SO EXPECT LINGERING
DRIZZLE/FREEZING DRIZZLE/FLURRIES TO DIMINISH AND END BY ABOUT
12Z...LAST IN THE UPSLOPE HIER TERRAIN AREAS OF THE NCNTRL. SOME LO
CLDS MAY LINGER A BIT LONGER...BUT EVEN THESE SHOULD DISSOLVE N-S BY
LATE MRNG. ALTHOUGH SHRTWV IN MN IS FCST TO SLIDE E AND BRING SOME
DPVA/DEEP LYR QVECTOR CNVGC MAINLY TO THE WI BORDER AREAS...INFLUX OF
LLVL DRY AIR WL PREVENT ANY PCPN AND LIMIT IMPACT TO JUST MORE MID/HI
CLDS. DESPITE THE RETURN OF SOME SUNSHINE ESPECIALLY OVER THE NRN
TIER...NE FLOW OFF THE CHILLY LK SUP WATERS WL LIMIT DIURNAL TEMP
RECOVERY TO NO HIER THAN ABOUT 40 NEAR THE LK. TEMPS WL TOP OUT ARND
50 OVER THE SCENTRAL.
TNGT...ANY LINGERING CLDS ASSOCIATED WITH THE SECOND SHRTWV WL CLR
THE FAR SCENTRAL BY 00Z THIS EVNG...SETTING THE STAGE FOR A CHILLY
NGT AS THE SFC HI PRES IN ONTARIO EXTENDS A SFC RDG AXIS INTO THE
UPR LKS UNDER LARGE SCALE SUBSIDENCE. THE ONLY LIMITING FACTOR WL BE
A PERSISTENT LIGHT NE FLOW TO THE S OF THE HI CENTER LINGERING OVER
ONTARIO. BUT WITH PWAT FALLING AOB 0.25 INCH...WL TEND TOWARD THE LO
END OF GUIDANCE FOR THE INTERIOR SHELTERED LOCATIONS.
.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 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 124 AM EDT TUE APR 26 2016
AS WEAK LOW SLIDES SE OF THE REGION OVERNIGHT...PCPN WILL BE
TAPERING OFF FM W TO E AND RAIN WILL MIX WITH OR CHANGE OVER TO SNOW
AT KCMX AND KSAW. WITH SHALLOW MOIST EASTERLY FLOW
CONTINUING...EXPECT IFR/LIFR CONDITIONS TO PERSIST AT KIWD/KCMX/KSAW
OVERNIGHT. 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 401 AM EDT TUE APR 26 2016
ENE WINDS UP TO 25-30 KTS OVER THE LAKE THIS MORNING...STRONGEST
OVER THE W...WILL DIMINISH THROUGH THE DAY TO UNDER 20 KTS AS A HI
PRES RIDGE BUILDS S THRU ONTARIO AND THE PRES GRADIENT WEAKENS. E TO
NE WINDS GENERALLY UNDER 20-25KT WILL THEN PREVAIL THRU SAT TO THE S
OF PERSISTENT HI PRES NEAR HUDSON BAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...VOSS
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
125 AM EDT TUE APR 26 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 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 124 AM EDT TUE APR 26 2016
AS WEAK LOW SLIDES SE OF THE REGION OVERNIGHT...PCPN WILL BE
TAPERING OFF FM W TO E AND RAIN WILL MIX WITH OR CHANGE OVER TO SNOW
AT KCMX AND KSAW. WITH SHALLOW MOIST EASTERLY FLOW
CONTINUING...EXPECT IFR/LIFR CONDITIONS TO PERSIST AT KIWD/KCMX/KSAW
OVERNIGHT. 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...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...VOSS
MARINE...ROLFSON
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
416 AM CDT TUE APR 26 2016
.Discussion...
Issued at 416 AM CDT TUE APR 26 2016
Early morning elevated convection will continue to fire south of a
stationary frontal boundary draped across northeast Kansas and
northern Missouri. A stout EML will continue to support modest
instability with further destabilization through the morning hours.
Storms early on will be relatively isolated and should remain north
of the I-70 corridor until daybreak. Overnight convection has been
slow to strengthen given the lack of instability, though should
start to see more widespread development in the early to mid morning
hours. A larger cluster of storms developing over north central
Kansas, where more supportive instability is present, will likely
generate a cold pool sufficient enough to steer nearby convection to
the southeast. As these elevated storms strengthen after daybreak,
some storms may produce large hail until the mid morning.
As this activity slides to the southeast through the late morning to
early afternoon, there should be a bit of a break in the activity
until the late afternoon and early evening hours. The anticipated
deep upper low will center across western Kansas while at the
surface, a dryline will reside from central Texas up to south
central Nebraska. Morning convection may limit instability to a
degree, though cloud cover should thin out enough to generate
surface based CAPE values over 2000 Jkg by the mid afternoon. More
robust convection will fire along the dry line well to the west of
the area through the early afternoon. This convection will then
slide into eastern Kansas and western Missouri by the late
afternoon. Will also need to monitor the potential for convection
ahead of the dryline within an area of surface convergence. As the
storms over eastern Kansas approach the area, will likely transition
to a linear mode with bowing segments. Large hail and damaging winds
will be the primary hazards, particularly for western Missouri,
though a few embedded tornadoes cannot be ruled out.
The next round of activity, which could be more pronounced for the
CWA, arrives during Wednesday as the dryline advances toward eastern
Kansas. Modest instability looks to develop across eastern Kansas
along with central and southwest Missouri as previous convection
clears out. Most of the expected convection should develop over
central and eastern Missouri, though will need to monitor points
west, particularly northwest Missouri as the stacked low could
produce a few tornadoes.
The active pattern will subside temporarily heading into Thursday
and Friday, though another upper low will deepen across the
southwest during this time. Could see late week convection by late
Friday as a warm front lifts north. A few rounds of storms with
potential severe storms will then develop through the weekend as the
surface low lifts to the northwest into the Central Plains.
&&
.Aviation...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1236 AM CDT TUE APR 26 2016
Active next 24 hours with showers and storms expected to blossom
across eastern KS and western MO over the next 2 to 6 hours and
continue off and on into late morning. Some of these storms could be
strong. Another round of storms is expected Tuesday evening, which
will likely be in the form of a north-south oriented line that will
track slowly from eastern KS into western MO after dark.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...Welsh
Aviation...Hawblitzel
[top]
Area Forecast Discussion
National Weather Service Saint Louis MO
407 AM CDT TUE APR 26 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 406 AM CDT Tue Apr 26 2016
A Rex Block pattern exists over the CONUS Rockies and Canadian
Prairie with a weak RIDGE over our region. A surface frontal
boundary at 07z extended from just south of Chicagoland west-
southwestward to just north of Quincy and near Kansas City. This
front, in the absence of any upper support and low level jet, will
be the primary focus for any convection that might develop thru late
this morning. Such as it is, a capping inversion has largely
suppressed the attempted convection in our region and so only a
slight chance is anticipated during this time.
The best focus thru early this morning will be to our west in
northeast Kansas and southeast Nebraska, where there will be a low
level jet and radar and satellite shows this is where the breaking
of the capping inversion has been most successful.
Short-term model guidance seems to have a loose consensus on the
convection that develops to our west congealing and then tracking
east along what should be a slowly southward sagging front over our
way. Have followed these trends for now with increasing PoPs into
central MO for late this morning, sliding into STL metro during
midday-early afternoon, and then into southern IL during the
afternoon. Peaked PoPs at 50% for now, but these will need to be
increased as confidence of this event waxes.
This convective event for late this morning and afternoon, and
especially the leading or eastern edge of it, will have some
potential for severe with marginal bulk shear values and CAPE of
around 2000 J/kg. It will very much depend on how organized the
convection can get early this morning before heading east.
Corresponding with a southward moving front and increased cloudiness
associated with this convective event later today, have edged back
on max temps, still preferring the MAV MOS values from upper 70s in
northeast MO and west-central IL to 80-85 elsewhere. Again, this
is all conditional on the rain event, so these will probably need
further massaging.
TES
.LONG TERM... (Tonight through Monday)
Issued at 406 AM CDT Tue Apr 26 2016
A complex forecast in the short term with multiple rounds of storms
thru mid-week.
Convection today will largely determine how events tonight will
unfold. In general, have trended twd the NSSL WRF/local 4km WRF
early in the period, then twd the GFS/ECMWF late tonight into Wed
morning. The 06z/26 NAM actually trended twd this idea as well.
The outflow boundary from today`s convection is expected to push any
activity S of the CWA this evening. As the trof over the Plains
becomes more negatively tilted and the sfc boundary lifting nwd back
into the area, expect more storms to move into the region late
tonight. Mdls still prog near 1000 J/kg elevated CAPE, with enuf
deep layer shear to support a threat for severe storms, mainly large
hail given elevated storms. Flooding will be another threat tonight
if storms today evolve as anticipated, with storms tonight traveling
over the same region. Due to uncertainty in precip today and
tonight, have held off on any headlines attm.
Expect convection to be ongoing at the beginning of the period Wed
along and N of the fnt. This convection is expected to push nwd as
the upper trof rotates nwd. The wrmfnt associated with this system
is expected to be draped across the central portions of the CWA and
will provide a focus for storm development Wed afternoon as a s/w
rotates thru the base of the trof. Cloud cover, and therefore
heating, near the fnt are still uncertain with mdls depicting mid
level warming that may keep the region capped. If this cap can be
broken, supercells with large hail will be possible along this fnt,
with what appears to be a triple point in central MO.
The bulk of what develops shud be N of the area by around Midnight
Thurs, but have kept higher PoPs to account for timing differences.
Once this precip exits the area, expect much of Thurs and Fri dry.
Active weather returns this weekend with sfc ridge building into the
region on Mon bringing much cooler temps to the region.
Tilly
&&
.AVIATION... (For the 06z TAFs through 06z Tuesday Night)
Issued at 1152 PM CDT Mon Apr 25 2016
Still looks like thunderstorms will develop late tonight over
western MO and move east into central MO. These storms may affect
KCOU and possibly the St. Louis metro terminals through mid
morning. A cold front currently over southeast Missouri and
northern Missouri will move southeast which could produce
additional thunderstorms during the day on Thursday. Any
thunderstorms that move over an airport could produce MVFR or
brief IFR ceilings and visibilities. There is also the possibility
that a few storms could produce hail and wind gusts over 50 kts.
Specifics for KSTL: There is a chance of showers and thunderstorms
through the period, particularly late Tuesday afternoon and
Tuesday night when a cold front will move into the area. Any
thunderstorms that move over the terminal could produce MVFR or
brief IFR ceilings and visibilities.
Britt
&&
.PRELIMINARY POINT TEMPS/POPS...
Saint Louis 82 64 80 58 / 50 80 80 50
Quincy 79 56 74 54 / 20 80 80 70
Columbia 81 61 80 54 / 50 80 70 30
Jefferson City 84 61 81 54 / 50 80 70 30
Salem 80 62 77 58 / 50 70 80 70
Farmington 81 61 77 56 / 50 80 80 50
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
[top]
Area Forecast Discussion
National Weather Service Springfield MO
251 AM CDT TUE APR 26 2016
.SYNOPSIS...
Issued at 251 AM CDT Tue Apr 26 2016
Convection starting to develop along a west east boundary across
northeast KS and west central MO near the I-70 corridor. Pretty
decent elevated mixed layer was located along and south of the
boundary and developing convection including our forecast area.
Surface low was located over the high plains with dryline from
western Kansas into the panhandle of OK and TX. South-southwest
low level jet and mid level diffluent flow was aiding in the
developing convection.
This is going to be a busy weather day/night for our CWA and
neighboring CWA`s to the west and will be the main focus with this
forecast package.
&&
.SHORT TERM...(Today and tonight)
Issued at 251 AM CDT Tue Apr 26 2016
Early morning convection will continue to increase north of the
CWA prior to sunrise nearer to the surface boundary. This activity
will gradually shift east today over mostly northern and central
MO, possibly affecting our central MO counties later today.
Further south within the EML, instability will increase
significantly with CAPES in excess of 3000 j/kg developing. Have
my doubts as to whether we will freely convect given the strength
of the thermal cap in place without a trigger, but will keep in
low end pops just in case. Best chance will be over central MO
where some outflow or ongoing convection may move into the area.
Dryline out west is likely to get active by midday as upper level
jet impinges on the central/southern plains and weakens the EML.
By late in the afternoon, the shear starts to become fairly strong
to our west and the combination with the strong instability
supports the moderate risk of severe storms from southern Nebraska
into central Kansas and Oklahoma. The best chances for supercells
moving into our area will be this evening and over our western
CWA, before they start to congeal into more of line segments. The
primary severe risk after that occurs will be damaging wind,
although we could still see tornadoes develop out of these line
segments through the rest of the evening and overnight hours.
.LONG TERM...(Wednesday through Monday)
Issued at 251 AM CDT Tue Apr 26 2016
Wednesday looks like a messy forecast. There will probably be
ongoing convection at 12z Wed to start the morning, but models are
clearing this out by late morning. With the front still to the
west, can enough instability develop in the wake of the first
complex for convection to refire in the afternoon. Best bet will
be over our eastern CWA, where the higher surface dewpoints will
hang around the longest. Current day 2 outlook shows this with
slight risk over the eastern half of our CWA. Would expect this
activity to clear our eastern CWA by mid to late evening.
There should be a brief break from the convective potential on
Thursday, before the active pattern brings in the next system on
Friday into the weekend. This has the potential to be a wet
weekend with closed upper level low sitting over the central U.S.
for quite awhile.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1145 PM CDT Mon Apr 25 2016
For the KSGF/KJLN/KBBG tafs: Scattered tstms are expected to
develop north of the taf sites over the next few hours close to
a warm front over northeast KS and northern MO. Some of this
activity may moves south toward the area by 12z-14z, but timing is
questionable. Will maintain vcts groups for KSGF and KJLN for now.
Low level moisture is expected to increase and have low end mvfr
or ifr ceilings at all sites toward 12z. Ceilings are expected to
lift between 15z-18z.
Additional storms are expected to develop late in the taf period
over the Plains and shift east into western MO.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SYNOPSIS...Lindenberg
SHORT TERM...Lindenberg
LONG TERM...Lindenberg
AVIATION...DSA
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1226 AM CDT TUE APR 26 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 06Z TAFS through 06Z Tuesday Night)
Issued at 1236 AM CDT TUE APR 26 2016
Active next 24 hours with showers and storms expected to blossom
across eastern KS and western MO over the next 2 to 6 hours and
continue off and on into late morning. Some of these storms could be
strong. Another round of storms is expected Tuesday evening, which
will likely be in the form of a north-south oriented line that will
track slowly from eastern KS into western MO after dark.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...CDB
Aviation...Hawblitzel
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1203 AM CDT TUE APR 26 2016
.UPDATE...
Issued at 914 PM CDT Mon Apr 25 2016
Have made some adjustments to PoP trends. Thunderstorms have had a
hard time developing over the CWA so far this evening as the 00Z
SGF sounding was showing a large inversion around 750mb. The RAP
is showing an increase in low level moisture convergence along
I-70 across western and central MO after midnight on the nose of a
40kt low level jet. This will be occuring at the same time a weak
shortwave will be approaching the area from the Central Plains.
Have shown an increase in scattered thunderstorms after midnight
over central Missouri that spreads into eastern Missouri towards
morning. There will be some risk for large hail with these storms
over central Missouri per the latest SPC outlook with MUCAPES of
1000-1500 J/kg and effective shear 30-35kts.
Going low temperatures still look good.
Britt
&&
.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 06z TAFs through 06z Tuesday Night)
Issued at 1152 PM CDT Mon Apr 25 2016
Still looks like thunderstorms will develop late tonight over
western MO and move east into central MO. These storms may affect
KCOU and possibly the St. Louis metro terminals through mid
morning. A cold front currently over southeast Missouri and
northern Missouri will move southeast which could produce
additional thunderstorms during the day on Thursday. Any
thunderstorms that move over an airport could produce MVFR or
brief IFR ceilings and visibilities. There is also the possibility
that a few storms could produce hail and wind gusts over 50 kts.
Specifics for KSTL: There is a chance of showers and thunderstorms
through the period, particularly late Tuesday afternoon and
Tuesday night when a cold front will move into the area. Any
thunderstorms that move over the terminal could produce MVFR or
brief IFR ceilings and visibilities.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Springfield MO
1159 PM CDT MON APR 25 2016
.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 06Z TAFS through 06Z Tuesday night)
Issued at 1145 PM CDT Mon Apr 25 2016
For the KSGF/KJLN/KBBG tafs: Scattered tstms are expected to
develop north of the taf sites over the next few hours close to
a warm front over northeast KS and northern MO. Some of this
activity may moves south toward the area by 12z-14z, but timing is
questionable. Will maintain vcts groups for KSGF and KJLN for now.
Low level moisture is expected to increase and have low end mvfr
or ifr ceilings at all sites toward 12z. Ceilings are expected to
lift between 15z-18z.
Additional storms are expected to develop late in the taf period
over the Plains and shift east into western MO.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Burchfield
LONG TERM...Griffin
AVIATION...DSA
Area Forecast Discussion...Updated
National Weather Service Saint Louis MO
915 PM CDT MON APR 25 2016
.UPDATE...
Issued at 914 PM CDT Mon Apr 25 2016
Have made some adjustments to PoP trends. Thunderstorms have had a
hard time developing over the CWA so far this evening as the 00Z
SGF sounding was showing a large inversion around 750mb. The RAP
is showing an increase in low level moisture convergence along
I-70 across western and central MO after midnight on the nose of a
40kt low level jet. This will be occuring at the same time a weak
shortwave will be approaching the area from the Central Plains.
Have shown an increase in scattered thunderstorms after midnight
over central Missouri that spreads into eastern Missouri towards
morning. There will be some risk for large hail with these storms
over central Missouri per the latest SPC outlook with MUCAPES of
1000-1500 J/kg and effective shear 30-35kts.
Going low temperatures still look good.
Britt
&&
.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 00z TAFs through 00z Tuesday Evening)
Issued at 619 PM CDT Mon Apr 25 2016
There is still some potential for scattered thunderstorms to
develop over the area this evening that could affect any of the
the terminals. This chance is too low however to include in any of
the TAFs at this point. Models are hinting that a complex of
storms could develop over western MO later tonight and move east
which would affect KCOU and possibly the St. Louis area terminals.
Have gone ahead and added VCTS at KCOU for a short period to
include this possibility. Cold front that currently extends from
southern Iowa into northern Missouri will move south into the area
by tomorrow afternoon. Additional scattered thunderstorms could
develop along it which could affect KCOU and the St. Louis area
terminals. Any thunderstorms that move over an airport could
produce MVFR or brief IFR ceilings and visibilities. There is
also the possibility that a few storms could produce hail and wind
gusts over 50 kts.
Specifics for KSTL: Have gone with a dry and VFR TAF for now,
however there will a 20-30 percent chance of thunderstorms through
the period. A cold front will move south to near the terminal
during the day tomorrow causing winds to shift to the southeast.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Springfield MO
645 PM CDT MON APR 25 2016
...00z Aviation Update...
.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 00Z TAFS through 00Z Tuesday evening)
Issued at 645 PM CDT Mon Apr 25 2016
VFR conditions can be expected at the start of this cycle. CIGs
will begin to lower later tonight and early tomorrow as stratus
build down takes over. To aid in this, a decent southerly surface
flow will continue to supply the area with plenty of low level
moisture. With the stratus build down, did go ahead and lower vis
into the MVFR range and dropped CIGs into IFR at least for a short
time early Tuesday.
Conditions will once again improve during the day to VFR by mid to
late afternoon. In terms of precipitation, low confidence at the
moment. Decided to keep only VCs going for now. The aforementioned
"decent" surface winds/flow may become a tad gusty tomorrow
afternoon over JLN. Speaking of wind, low level wind shear will be
present overnight tonight with an increasing LLJ, especially over
JLN and SGF.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Burchfield
LONG TERM...Griffin
AVIATION...Frye
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
644 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 00z TAFs through 00z Tuesday Evening)
Issued at 619 PM CDT Mon Apr 25 2016
There is still some potential for scattered thunderstorms to
develop over the area this evening that could affect any of the
the terminals. This chance is too low however to include in any of
the TAFs at this point. Models are hinting that a complex of
storms could develop over western MO later tonight and move east
which would affect KCOU and possibly the St. Louis area terminals.
Have gone ahead and added VCTS at KCOU for a short period to
include this possibility. Cold front that currently extends from
southern Iowa into northern Missouri will move south into the area
by tomorrow afternoon. Additional scattered thunderstorms could
develop along it which could affect KCOU and the St. Louis area
terminals. Any thunderstorms that move over an airport could
produce MVFR or brief IFR ceilings and visibilities. There is
also the possibility that a few storms could produce hail and wind
gusts over 50 kts.
Specifics for KSTL: Have gone with a dry and VFR TAF for now,
however there will a 20-30 percent chance of thunderstorms through
the period. A cold front will move south to near the terminal
during the day tomorrow causing winds to shift to the southeast.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
635 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 00Z TAFS through 00Z Tuesday Evening)
Issued at 635 PM CDT MON APR 25 2016
Front remains draped across the lower Missouri Valley this
evening and it will be this feature that serves as focusing
mechanism for developing shwrs/storms after midnight as the low-
level jet begins impinging upon the boundary. For now...best coverage
of storms looks to occur after the 08z time frame...and tempo groups
have been inserted for all terminals. As storms develop...IFR
conditions will remain possible through the mid-morning hrs before
conditions improve towards 14z. Otherwise...dry conditions to prevail
through much of the remaining daylight hrs with storms again becoming
likely after the conclusion of the fcst period.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...CDB
Aviation...32
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
635 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 00Z TAFS through 00Z Tuesday Evening)
Issued at 635 PM CDT MON APR 25 2016
Front remains draped across the lower Missouri Valley this
evening and it will be this feature that serves as focusing
mechanism for developing shwrs/storms after midnight as the low-
level jet begins impinging upon the boundary. For now...best coverage
of storms looks to occur after the 08z time frame...and tempo groups
have been inserted for all terminals. As storms develop...IFR
conditions will remain possible through the mid-morning hrs before
conditions improve towards 14z. Otherwise...dry conditions to prevail
through much of the remaining daylight hrs with storms again becoming
likely after the conclusion of the fcst period.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...CDB
Aviation...32
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
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
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 HASTINGS NE
325 AM CDT TUE APR 26 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 321 AM CDT TUE APR 26 2016
SATELLITE AND OBSERVATIONS SHOW SOME STRATUS SPREADING ACROSS THE
FORECAST AREA THIS MORNING. RADAR HAS A SINGLE CELL IN NORTH CENTRAL
KANSAS AND MAYBE A FEW SPRINKLES ACROSS SOUTHWEST NEBRASKA.
STILL A LOT OF DIFFERENCES IN THE MODELS THIS MORNING CONSIDERING
THAT THE MAIN EVENT IS LESS THAN 24 HOURS OUT. NEARLY ALL OF THE
MODELS HAVE THERE BEING PRECIPITATION ACROSS THE ENTIRE FORECAST
AREA THROUGH MUCH OF THE PERIOD. THE DETAILS ARE THE PART THAT
CREATE THE CHALLENGE. THE UPPER LOW IS TO THE WEST OF THE FORECAST
AREA AND THE FIRST WAVE OF ENERGY FROM THE LOW IS MOVING INTO THE
AREA EARLY THIS MORNING. THE SURFACE LOW IS STILL TO THE
WEST/SOUTHWEST OF THE FORECAST AREA THIS MORNING AND THERE IS A WARM
FRONT THAT EXTENDS TO THE EAST OF THE FRONT ACROSS NORTHERN KANSAS.
THE CURRENT CONVECTION IS TO THE NORTH OF THE FRONT IN AN AREA OF
WARM MOIST ADVECTION. THE INCREASE OF LOW LEVEL MOISTURE HAS THE
POTENTIAL TO BRING SOME FOG AND MAYBE SOME DRIZZLE TO THE AREA. THE
MAIN AREA WOULD BE TO THE NORTH OF THE FRONT. FOR NOW HAVE SOME
AREAS OF DRIZZLE AND PATCHY FOG.
WITH THE START OF THE CONVECTION ALREADY IN NORTH CENTRAL KANSAS
THERE IS ALREADY SIGNIFICANT CAPE AND SHEAR AND THUNDERSTORMS THIS
MORNING WOULD LIKELY BE SEVERE. THIS ACTIVITY SHOULD BE DECREASING
AROUND SUNRISE AS IT MOVES TO THE EAST.
ONE OF THE MAIN VARIABLES FOR TODAY AND TONIGHT IS THE LOCATION OF
THE SURFACE LOW AND WARM FRONT. SOME OF THE MODELS PUSH THE WARM
FRONT TO THE NORTH...WHILE OTHERS KEEP IT FURTHER TO THE SOUTH. HAVE
KEPT WITH THE FURTHER SOUTH THEORY SINCE THERE COULD BE STRATUS
AROUND THIS MORNING AND INTO THE EARLY AFTERNOON THAT WOULD SLOW THE
FRONT MOVING TO THE NORTH. MOST OF THE MODELS ALSO KEEP THE SURFACE
LOW NEAR THE KANSAS/NEBRASKA BORDER THROUGH THE DAY.
THE NEXT QUESTION WILL BE HOW MUCH PRECIPITATION WILL THERE BE MID
MORNING TO MID AFTERNOON. THE NAM...GFS...ECMWF AND A FEW OF THE
SHORT TERM MODELS HAVE CONVECTION SPREADING ACROSS THE FORECAST AREA
DURING THE MORNING HOURS. ON THE OTHER HAND THE HRRR AND SOME OF THE
OTHER SHORT TERM MODELS HAVE A DRY OR NEARLY DRY PERIOD FOR MID DAY.
HAVE KEPT THE POPS DURING THE DAY...BUT HAVE A FEW CONCERNS HOW MUCH
THERE WILL BE.
WHEN WILL CONVECTION GET GOING THIS AFTERNOON? MOST OF THE MODELS
HAVE CONVECTION STARTING SOMETIME AROUND 21 TO 00Z THIS AFTERNOON
AND CONTINUING THROUGH THE NIGHT. THE BEST CHANCES WILL BE DURING
THE EVENING HOURS. ANOTHER CONCERN IS THAT SOME OF THE MODELS ARE
BRINGING IN A DRY SLOT INTO THE SOUTHERN PORTION OF THE FORECAST
AREA. WILL HAVE TO WATCH THIS TO SEE JUST WHERE AND HOW FAR IT MOVES
INTO THE AREA LATE TONIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 321 AM CDT TUE APR 26 2016
IT IS NO QUESTION THAT THE MAIN CONCERNS LIE WITHIN THE SHORT-
TERM...BUT THE MID AND EXTENDED ARE STILL ACTIVE AND INTERESTING
IN THEIR OWN RIGHT.
MID-TERM (WEDNESDAY - THURSDAY):
THE MAIN FOCUS IN THIS PERIOD IS THE EXIT OF THE UPPER LEVEL LOW
THAT BEGINS TO IMPACT US TODAY. ONCE THE UPPER DISTURBANCE ROTATES
FROM THE SOUTHWEST INTO NEBRASKA EARLY WEDNESDAY MORNING IT
BECOMES RELATIVELY STAGNANT AND SLOW MOVING. THIS CAUSED THE
MULTIPLE PV ANOMALIES ROTATING AROUND THE UPPER LOW TO CAUSE
CHANCES FOR RAIN THROUGHOUT WEDNESDAY. THINK THE BEST CHANCES WILL
BE OVER SOUTH CENTRAL NEBRASKA ALONG AND NORTH OF WHERE THE
SURFACE LOW TRACKS. THERE ARE SOME DISCREPANCIES ON HOW THE
QUICKLY THE UPPER LOW EJECTS EASTWARD WITH THE GFS AND EC MORE
PROGRESSIVE WHILE THE NAM ROTATES THE ENERGY BACK NORTHWARD OVER
THE NORTHERN PLAINS. REGARDLESS THINK PRECIPITATION WILL WANE LATE
WEDNESDAY AND THAT THE ARE WILL BE MOSTLY DRY WEDNESDAY OVERNIGHT
INTO THURSDAY MORNING.
THURSDAY IS EXPECTED TO BE DRY...BUT THE ACTIVE PATTERN CONTINUES
AS THE NEXT DISTURBANCE APPROACHES FROM THE WEST THURSDAY NIGHT.
IN THE WARM SECTOR AHEAD OF THE NEXT WAVE PRECIPITATION IS
EXPECTED TO DEVELOP FROM SOUTHWEST MOVING TO THE NORTHEAST.
LONG-TERM (FRIDAY - MONDAY):
THIS PERIOD IS LIKELY TO BE WET AT LEAST OFF AND ON. THE UPPER LOW
WILL PROGRESS EASTWARD SLOWLY WHILE THE SURFACE LOW TRACKS
NORTHEAST ACROSS THE AREA AS WELL. PRECIPITATION POTENTIAL IS
FAIRLY HIGH. WATER COULD BE COME A CONCERN. WATCH THIS PERIOD AS
IT NEARS.
THE MAJORITY OF THE FORECAST WAS FOCUSED ON THE SHORT AND MID-TERM
WITH ONGOING CONVECTION...THE LONG-TERM FORECAST IS ABBREVIATED
BECAUSE OF THIS.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1208 AM CDT TUE APR 26 2016
A COUPLE OF CONCERNS FOR THIS FORECAST PERIOD. FIRST THERE WILL BE
LOW LEVEL MOISTURE ADVECTION INTO THE AREA THROUGH MUCH OF THE
PERIOD. THROUGH MID DAY THERE WILL BE AN INCREASE IN LOWER
CLOUDS AND THERE COULD BE SOME DRIZZLE AND PERHAPS SOME FOG.
CURRENTLY THERE ARE NOT LOCATIONS THAT HAVE EXTREMELY LOW CEILINGS
AND VISIBILITY BUT EXPECT THAT TO CHANGE TOWARD DAY BREAK. HAVE
MVFR IN THERE NOW...BUT THERE COULD BE SOME IFR AROUND SUNRISE.
THE NEXT CONCERN IS A CHANCE FOR THUNDERSTORMS. THERE COULD BE
SOME DURING THE MORNING...BUT THE BETTER CHANCE WILL BE THIS
AFTERNOON AND EVENING.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...JCB
LONG TERM...BILLINGS WRIGHT
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1235 AM CDT TUE APR 26 2016
.UPDATE...
ISSUED AT 1222 AM CDT TUE APR 26 2016
PREVIOUS FORECAST IS IN GOOD SHAPE. JUST A FEW MINOR TWEAKS WERE
MADE TO THE PRECIPITATION FORECAST TO MATCH CURRENT TRENDS. LIGHT
SNOW CONTINUES ACROSS SOUTHWEST NORTH DAKOTA...MAINLY ALONG I-94
BETWEEN BELFIELD AND GLEN ULLIN. TEMPERATURES ARE RIGHT NEAR
FREEZING WHICH HAS LED TO MINOR ACCUMULATIONS. SOME MINOR
ACCUMULATIONS ON ROADS AND 1 TO 2 INCHES ON GRASSY AREAS IS
EXPECTED. FURTHER EAST LIGHT RAIN AND DRIZZLE CONTINUES.
UPDATE ISSUED AT 923 PM CDT MON APR 25 2016
LIGHT SNOW NOW ACROSS MUCH OF WEST CENTRAL NORTH DAKOTA AS
TEMPERATURES HAVE FALLEN INTO THE LOWER 30S. ALSO HAVE 1 TO 2
INCHES OF SNOW FOR THIS AREA TONIGHT.
UPDATE ISSUED AT 611 PM CDT MON APR 25 2016
TEMPERATURES REMAIN NEAR THE RAIN/SNOW THRESHOLD ACROSS SOUTHWEST
AND WEST CENTRAL NORTH DAKOTA THIS EVENING. WHILE THERE MAY BE A
SPOT OR TWO OF SLEET MIXED IN FOR THE MOST PART A MIX OF RAIN AND
SNOW LOOKS TO PREDOMINATE. TWEAKED THE TEMPERATURES A BIT COOLER
THROUGH THE EVENING HOURS WHICH WILL MAINTAIN MORE SNOW AS A
WEATHER ELEMENT WEST. OTHERWISE SINCE TEMPERATURES BOTTOM OUT IN
THE LOWER 30S DONT EXPECT ACCUMULATIONS MORE THAN AN INCH ON
GRASSY AREAS WEST CENTRAL TONIGHT.
&&
.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 ANALYSES. 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 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1222 AM CDT TUE APR 26 2016
WIDESPREAD IFR CONDITIONS WILL CONTINUE ACROSS SOUTHERN NORTH DAKOTA
TONIGHT AND THROUGH MUCH OF TUESDAY. AREAS OF LIGHT SNOW AT KDIK AND
RAIN AT KBIS AND KJMS. KISN AND KMOT WILL REMAIN ALONG THE NORTHERN
FRINGE OF MVFR CLOUDINESS. CURRENTLY AT 06 UTC THEY REMAIN VFR BUT
COULD CERTAINLY SEE PERIOD OF MVFR LATE TONIGHT THROUGH TUESDAY
MORNING. SOUTHERN TAF SITES WILL LIKELY REMAIN MVFR-IFR THROUGH THE
DAY TUESDAY. RAIN CHANCES WILL LESSEN DURING THE DAY TUESDAY BUT
PICK UP BY LATE AFTERNOON/EARLY EVENING FROM KDIK TO KISN AND KBIS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AJ
SHORT TERM...CJS
LONG TERM...CJS
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
237 AM EDT TUE APR 26 2016
.SYNOPSIS...
COLD FRONT SINKS SOUTH INTO OUR FORECAST AREA TODAY. FRONT WAFFLES
BACK/FORTH IN OUR VICINITY THROUGH THURSDAY NIGHT...PROVIDING FOR
ROUNDS OF SHOWERS AND THUNDERSTORMS.
&&
.NEAR TERM /THROUGH TONIGHT/...
WARM MORNING TODAY WITH HRRR SUGGESTING A LITTLE BIT OF
CONVECTION THIS MORNING...BUT HAVE YET TO SEE IT MATERIALIZE ON
RADAR.
MAIN FEATURE TODAY WILL BE THE COLD FRONT SINKING DOWN FROM THE
NORTH. THIS WILL INCREASE CLOUDS AND INSTABILITY FOR SCT THUNDERSTORMS
THIS AFTERNOON. THERE IS A LITTLE BIT OF SEVERE POTENTIAL WITH
THESE STORMS WITH 1000+ J/KG CAPE...35 KT OF DEEP LAYER SHEAR...AND
250 M2/S2 OF SRH COULD PRODUCE A FEW ROTATING STORMS WITH THE
BIGGEST SEVERE THREAT BEING HAIL/WIND. SPC HAS US MARGINALLY
RISKED WHICH SEEMS LIKE A FAIR ASSESSMENT.
THE FRONT LAYS OUT TONIGHT BUT WILL KEEP INCLEMENT WEATHER AROUND
THE AREA THROUGH MUCH OF THE WEEK.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
MODELS ARE STRUGGLING WITH THIS PATTERN...PROVIDING VARIOUS
SOLUTIONS. THIS LEADS TO LOW CONFIDENCE IN THE TIMING OF VARIOUS
FEATURES AND ASSOCIATED ROUNDS OF SHOWERS AND THUNDERSTORMS. WILL
LOWER POPS WEDNESDAY NIGHT TO REFLECT THIS UNCERTAINTY. WILL ALSO
KEEP THE CURRENT FORECAST FROM THURSDAY NIGHT ONWARD FOR
CONSISTENCY...ESPECIALLY CONSIDERING THAT CONFIDENCE IN ANY ONE
SOLUTION IS NOT HIGH.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
MODELS IN AGREEMENT WITH LOW PRESSURE MOVING THROUGH THE AREA ON
FRIDAY AND EXITING OFF THE ATLANTIC COAST LATE FRIDAY NIGHT. ANY
SHOWERS WILL EXIT WITH THIS SYSTEM. SATURDAY LOOKS TO BE THE
BEST DAY OUT OF THE WEEKEND WITH WEAK RIDGING TAKING HOLD.
SUNDAY THROUGH MONDAY IS WHERE THE CONFIDENCE OF THE FORECAST
DIMINISHES. BOTH THE GFS AND ECMWF DEVELOP SYSTEM OUT TO OUR
WEST, BUT TIMING AND POSITION OF THE SYSTEMS DIFFER. THE GFS
BRINGS A WARM FRONTAL BOUNDARY UP ACROSS THE AREA AND DEVELOPS A
LOW PRESSURE SYSTEM THAT TRACKS ACROSS THE SOUTHERN PORTION OF THE
CWA. THE ECMWF DEVELOPS THE LOW AND TRACKS IT NORTH OF THE CWA
THROUGH MONDAY. IN ANY CASE THERE WILL BE SHOWERS AROUND. WITH
THIS SCENARIO, INTRODUCE LIKELY POPS OVER MUCH OF THE AREA ON
SUNDAY AND KEPT CHANCE POPS EVERYWHERE MONDAY.
&&
.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
AROUND 30 KT OF LLWS THIS MORNING AS LOW LEVEL JET SNEAKS IN WITH
LOWER ATMOSPHERE DECOUPLED. VFR THOUGH MVFR/IFR CONDITIONS
POSSIBLE IN SHOWERS OR STORMS THIS AFTERNOON. MVFR OR IFR
CONDITIONS ARE EXPECTED BEHIND THE FRONT TONIGHT INTO WEDNESDAY.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: COVERAGE OF SHOWERS COULD BE MORE THAN EXPECTED BY 18Z
TODAY. IFR MAY BE A POSSIBILITY IN WAKE OF FRONT AS DEEP LOW LEVEL
SATURATION OCCURS.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE TUE 04/26/16
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H H H H H H H H H H M
HTS CONSISTENCY H H H H H H H H H H H M
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H M
PKB CONSISTENCY H H H H H H H H H M M M
CKB CONSISTENCY H H H H H H H H H M M H
AFTER 06Z WEDNESDAY...
IFR POSSIBLE IN ROUNDS OF SHOWERS OR STORMS THROUGH THURSDAY. LOW
CEILINGS MAY ALSO FORM WEDNESDAY MORNING NORTH OF THE STALLED
FRONT.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JS/RPY/JW
NEAR TERM...JW
SHORT TERM...RPY
LONG TERM...JS
AVIATION...JW
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
231 AM EDT TUE APR 26 2016
.SYNOPSIS...
COLD FRONT SINKS SOUTH INTO OUR FORECAST AREA TODAY. FRONT
WAFFLES BACK/FORTH IN OUR VICINITY THROUGH THURSDAY NIGHT.
BOUNDARY PROVIDES OPPORTUNITIES FOR ROUNDS OF SHOWERS/STORMS.
&&
.NEAR TERM /THROUGH TONIGHT/...
WARM MORNING TODAY WITH HRRR SUGGESTING A LITTLE BIT OF
CONVECTION THIS MORNING...BUT HAVE YET TO SEE IT MATERIALIZE ON
RADAR.
MAIN FEATURE TODAY WILL BE THE COLD FRONT SINKING DOWN FROM THE
NORTH. THIS WILL INCREASE CLOUDS AND INSTABILITY FOR SCT TSTORMS
THIS AFTERNOON. THERE IS A LITTLE BIT OF SEVERE POTENTIAL WITH
THESE STORMS WITH 1000+ J/KG CAPE...35 KT OF DEEP LAYER SHEAR...AND
250 M2/S2 OF SRH COULD PRODUCE A FEW ROTATING STORMS WITH THE
BIGGEST SEVERE THREAT BEING HAIL/WIND. SPC HAS US MARGINALLY
RISKED WHICH SEEMS LIKE A FAIR ASSESSMENT.
THE FRONT LAYS OUT TONIGHT BUT WILL KEEP INCLEMENT WEATHER AROUND
THE AREA THROUGH MUCH OF THE WEEK.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
THERE IS MUCH MODEL DISCREPANCY IN THE MASS AND QPF FIELDS THIS
PERIOD...AS THE INTERACTION BETWEEN THE NORTHERN STREAM FLOW ACROSS
THE GREAT LAKES AND NEW ENGLAND AND THE CLOSED UPPER LOW OVER THE
PLAINS STATES IS UNCERTAIN. CONFIDENCE IN TIMING...ESPECIALLY LATER
IN THE PERIOD IS RATHER LOW. WHILE MODELS AGREE THERE WILL BE ENOUGH
PUSH OF THE COLD FRONT SOUTHWARD INTO THE AREA TUESDAY NIGHT...HOW
FAR SOUTH IT GETS BEFORE STALLING IS A BIG QUESTION. IN ADDITION...
WHEN AND HOW FAST THE FRONT THEN RETURNS NORTHWARD AS A WARM FRONT AS
THE UPPER LOW TO THE WEST STARTS EJECTING EASTWARD IS ALSO A QUESTION.
THE BEST SOLUTION AT THIS TIME IS TO TAKE A BLEND OF THE SOLUTIONS.
THIS ACCEPTED SOLUTION WILL BRING ABOUT A WET PERIOD WITH THE FRONT
BASICALLY HANGING AROUND THE AREA. GOOD INSTABILITY IS SHOWN WITH
THE FRONT...SO THUNDER INCLUDED MOST AREAS MOST OF THE TIME...BUT
TOO EARLY TO MENTION OTHER THAN GENERAL THUNDER.
SPECIFICALLY...WE HAVE THE FRONT AT THE BEGINNING OF THE PERIOD IN
FAR NORTHERN ZONES...DROPPING SOUTH INTO THE SOUTHERN COAL FIELDS
BEFORE STALLING TUESDAY NIGHT. THE FRONT WILL THEN START TO
RETURN SLOWLY NORTHWARD LATER WEDNESDAY AHEAD OF THE EJECTING UPPER
LOW...LIFTING NORTH OF THE AREA DURING THURSDAY. BEST POPS/QPF WILL
THEN ACCOMPANY THE FRONT FROM NORTH TO SOUTH TUESDAY NIGHT...LESSENING
SOMEWHAT BEFORE THE FRONT RETURNS NORTHWARD LATE WEDNESDAY INTO THE
THURSDAY MORNING. THURSDAY AFTERNOON SHOULD PLACE US IN THE WARM SECTOR...
BUT STILL A LOWER CHANCE OF SHOWERS AND STORMS THURSDAY AFTERNOON GIVEN
THE CONTINUING INSTABILITY. AT THIS TIME WE HAVE NO HAZARDOUS
WEATHER MENTIONED FOR THIS PERIOD.
TEMPERATURES WOULD HIGHLY DEPEND ON THE CLOUDS AND SHOWERS. DESPITE GOING
WITH GENERALLY UNSETTLED WEATHER AND CLOUDS...WE LOOK FOR HIGHS
SLIGHTLY ON THE HIGHER SIDE OF GUIDANCE BY DAY AND ON THE HIGHER
SIDE BY NIGHT.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
MODELS IN AGREEMENT WITH LOW PRESSURE MOVING THROUGH THE AREA ON
FRIDAY AND EXITING OFF THE ATLANTIC COAST LATE FRIDAY NIGHT. ANY
SHOWERS WILL EXIT WITH THIS SYSTEM. SATURDAY LOOKS TO BE THE
BEST DAY OUT OF THE WEEKEND WITH WEAK RIDGING TAKING HOLD.
SUNDAY THROUGH MONDAY IS WHERE THE CONFIDENCE OF THE FORECAST
DIMINISHES. BOTH THE GFS AND ECMWF DEVELOP SYSTEM OUT TO OUR
WEST, BUT TIMING AND POSITION OF THE SYSTEMS DIFFER. THE GFS
BRINGS A WARM FRONTAL BOUNDARY UP ACROSS THE AREA AND DEVELOPS A
LOW PRESSURE SYSTEM THAT TRACKS ACROSS THE SOUTHERN PORTION OF THE
CWA. THE ECMWF DEVELOPS THE LOW AND TRACKS IT NORTH OF THE CWA
THROUGH MONDAY. IN ANY CASE THERE WILL BE SHOWERS AROUND. WITH
THIS SCENARIO, INTRODUCE LIKELY POPS OVER MUCH OF THE AREA ON
SUNDAY AND KEPT CHC POPS EVERYWHERE MONDAY.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
VFR THOUGH MVFR/IFR CONDITIONS POSSIBLE IN SHOWERS OR STORMS
THIS AFTERNOON. MVFR OR IFR CONDITIONS ARE EXPECTED BEHIND THE
FRONT TONIGHT INTO WEDNESDAY.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: COVERAGE OF SHOWERS COULD BE MORE THAN EXPECTED BY 18Z
TODAY. IFR MAY BE A POSSIBILITY IN WAKE OF FRONT AS DEEP LOW LEVEL
SATURATION OCCURS.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE TUE 04/26/16
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H H H H H H H H H H M
HTS CONSISTENCY H H H H H H H H H H H M
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H M
PKB CONSISTENCY H H H H H H H H H M M M
CKB CONSISTENCY H H H H H H H H H M M H
AFTER 06Z WEDNESDAY...
IFR POSSIBLE IN ROUNDS OF SHOWERS OR STORMS THROUGH THURSDAY. LOW
CEILINGS MAY ALSO FORM WEDNESDAY MORNING NORTH OF THE STALLED
FRONT.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JS/KTB/JMV/JW
NEAR TERM...JW
SHORT TERM...JMV
LONG TERM...JS
AVIATION...JW
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
102 AM EDT TUE APR 26 2016
.SYNOPSIS...
WEAKENING LOW PRESSURE WILL MOVE EAST ALONG A STATIONARY
FRONT NEAR LAKE ERIE LATE TONIGHT INTO TUESDAY PULLING THE FRONT
SOUTH OF THE OHIO RIVER BY TUESDAY NIGHT. ANOTHER LOW WILL MOVE OUT
OF THE PLAINS WEDNESDAY NIGHT AND SLOWLY MOVE UP THE OHIO RIVER
THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
UPDATE...FOLLOWED THE HRRR PROGRESSION OF THE CONVECTION TO OUR
WEST WHICH DROPS IT SOUTHEAST ACROSS THE AREA OVERNIGHT. SREF
AGREES. HAVE ADJUSTED POPS TO SHOW A LINE/AREA OF CONVECTION
SAGGING SOUTHEAST WITH LIKELY POPS. CONTINUED WITH LOWER THUNDER
CHANCES AS CONVECTION SHOULD BE WEAKENING AS TO DROPS THROUGH. NO
OTHER BIG CHANGES.
ORIGINAL...WARM FRONT WILL SLOWLY LIFT NORTHWARD THROUGH THE
EVENING WITH UNCERTAINTY ABOUT IF IT WILL BE LIFTING ACROSS LAKE
ERIE. MOISTURE LEVELS ARE INCREASING BUT REMAINS RATHER SHALLOW.
THIS WILL MAKE IT DIFFICULT FOR ANY SHOWERS/THUNDER TO DEVELOP
ALONG THE WARM FRONT/WEAK LAKE BOUNDARY INTERACTION ACROSS THE
NORTHEAST PORTION OF THE COUNTY WARNING AREA. WILL STILL KEEP A
SLIGHT CHANCE/CHANCE MENTION FOR THIS AREA DURING THE EARLY
EVENING. CURRENT THINKING IS THAT THE CHANCES OF
SHOWERS/THUNDERSTORMS WILL NOT INCREASE UNTIL AFTER DARK AS THE
COLD FRONT MOVES TOWARD NW OHIO. THE LOW IS WEAKENING AS IT MOVES
EASTWARD OVERNIGHT WHICH SHOULD SLOW THE EASTWARD MOVEMENT OF THE
COLD FRONT. THE FRONT MAY BE ABOUT HALF WAY ACROSS THE COUNTY
WARNING AREA BY 12Z. THE COVERAGE OF THE SHOWERS AND THUNDERSTORMS
REMAINS UNCERTAIN WITH THE BEST COVERAGE OCCURRING ACROSS THE
NORTHEAST CWA. WE WILL NEED TO MONITOR THE CONVECTION THAT
DEVELOPS NEAR CHICAGO IN CASE IT SENDS A SIGNIFICANT OUTFLOW
BOUNDARY TOWARDS WESTERN OHIO.
IT WILL BE A WARM NIGHT WITH LOWS IN THE 50S. SLIGHTLY COOLER NEAR
THE LAKE.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
COLD FRONT WILL SLOWLY CROSS THE AREA THROUGH MONDAY MORNING. AS
THE WEAKENING LOW MOVES ACROSS THE REGION INTO CENTRAL PA TUESDAY
AFTERNOON WINDS WILL BECOME NORTHERLY PUSHING THE MOISTURE AND
WARMTH SOUTHWARD. HIGH PRESSURE WILL RIDGE INTO THE AREA FROM
CENTRAL CANADA ON WEDNESDAY KEEPING A FRONTAL BOUNDARY DOWN NEAR
THE OHIO RIVER VALLEY. THIS BOUNDARY WILL LIFT BACK TOWARD
NORTHERN OHIO AND NW PA WEDNESDAY NIGHT INTO THURSDAY WITH RAIN
CHANCES INCREASING FROM THE SOUTHWEST TO THE NORTHEAST. IT MAY
TAKE WELL INTO THURSDAY AFTERNOON FOR NW PA TO SEE ANY OF THE
RAIN. LOW PRESSURE THURSDAY AFTERNOON AND EVENING SHOULD TRACK
EASTWARD ALONG THE FRONTAL BOUNDARY THAT MAY LIFT AS FAR
NORTHWARD AS CENTRAL OHIO.
AFTER MORNING/EARLY AFTERNOON HIGHS ON TUESDAY THE TREND WILL BE
DOWNWARD. HIGHS WEDNESDAY AND THURSDAY SHOULD REMAIN IN THE 50S
NORTH AND 60S SOUTH. COLDEST NEAR THE LAKE WITH UPPER 40S
POSSIBLE.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
LONG TERM BEGINS ON FRIDAY AND MODELS ARE IN GOOD AGREEMENT ON AN
UPPER LEVEL SHORTWAVE TROUGH THAT WILL MOVE THROUGH THE GREAT LAKES
REGION. A WEAK SURFACE LOW PRESSURE SYSTEM ASSOCIATED WITH THIS
TROUGH WILL MEANDER EASTWARD ON FRIDAY BRINGING SLIGHT CHANCE TO
CHANCE POPS TO THE REGION THROUGH FRIDAY EVENING. ON SATURDAY MODELS
SHOW SOME UPPER LEVEL RIDGING BUILDING BEHIND THE TROUGH AND ALLOW
FOR A BREAK IN PRECIPITATION CHANCES FOR SATURDAY. GFS AND ECMWF
VARY ON THE INTENSITY OF THE RIDGE AND THE TIMING OF THE FOLLOWING
UPPER LEVEL TROUGH. THE GFS HAS A WEAKER RIDGE ON SATURDAY THAT
GIVES WAY TO A WEAK SHORTWAVE TROUGH BY MONDAY. ECMWF HAS A HIGHER
AMPLITUDE RIDGE ON SATURDAY BUT THE FOLLOWING TROUGH IS STRONGER AND
BECOMES CUT OFF OVER THE GREAT LAKES. GIVEN DIFFERING SOLUTIONS
BIASED MORE TOWARDS THE ECMWF AS GFS HAS NOT DONE AS WELL HANDLING
THE PRESENT WEATHER. THUS HAVE INCREASED POPS FOR SUNDAY AND MONDAY
AND LEFT A SLIGHT CHANCE OF THUNDER FOR SUNDAY AS AIRMASS COULD BE
MODESTLY UNSTABLE.
TEMPERATURES THROUGH THE PERIOD WILL BE AT OR BELOW CLIMATOLOGY.
LONG TERM LOOKS ACTIVE WITH CLOUDS AND RAIN WITH WINDS PREDOMINATELY
OUT OF THE NORTH/NORTHEAST...ALL OF WHICH WOULD PROMOTE TEMPERATURES
TO BE ON THE COOLER SIDE.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
LOW PRESSURE OVER SRN LMIC WILL MOVE EAST ALONG A STATIONARY FRONT
INTO NRN PA THIS MORNING PULING THE FRONT SOUTH OF OUR TAF SITES
EARLY THIS AFTERNOON. A BAND OF SHRA/TSRA OVER SRN MI WILL PUSH SE
ACROSS THE AREA AND SHOULD BE SE OF CAK AND YNG BY ABOUT 11Z. SOME
ADDITIONAL SCT SHRA WILL PROBABLY DEVELOP OVER THE SNOWBELT AREA SW
TO NEAR MFR MID MORNING INTO EARLY AFTERNOON THEN SHIFT SE OUT OF
THE AREA. THE MODELS SHOW HIGH RH AT LOW LEVELS SPREADING SOUTH
ACROSS THE AREA BEHIND THE FRONT AND LASTING INTO TONIGHT. EXPECT
MVFR/IFR TO DEVELOP THIS MORNING AND CONTINUE INTO TONIGHT BEFORE
DRIER AIR ARRIVES TO BRING IMPROVEMENT.
SW WINDS OF 5 TO 12 KNOTS WILL TURN TO THE NW WITH THE FRONTAL
PASSAGE AND INCREASE TO 10 TO 20 KNOTS WHILE CONTINUING TO VEER TO
THE NE THIS AFTERNOON THRU EARLY TONIGHT.
OUTLOOK...NON-VFR LATE WED NIGHT THROUGH FRI...AND PROBABLY AGAIN
SAT NIGHT.
&&
.MARINE...
A WARM FRONT INTO CENTRAL OHIO WILL LIFT TO NEAR ERIE LAKESHORE THIS
EVENING AND THEN STALL. LOW PRESSURE SYSTEM IN IOWA WILL RIDE ALONG
THE BOUNDARY ACROSS OHIO OVERNIGHT. THE SYSTEM WILL PUSH SOUTHEAST
OF THE AREA TUESDAY...DRAGGING A COLD FRONT ACROSS THE AREA. SMALL
CRAFT ADVISORY POSSIBLE SOMETIME TUESDAY INTO TUESDAY NIGHT AS THE
NORTHEAST FLOW OVER THE LAKE INCREASES TO 10 TO 20 KNOTS BEHIND THE
SYSTEM. EAST TO NORTHEAST WINDS WILL CONTINUE ON THE LAKE INTO NEXT
WEEKEND AS HIGH PRESSURE BECOMES ESTABLISHED OVER CENTRAL CANADA.
WINDS WILL INCREASE THURSDAY AS LOW PRESSURE MOVES ACROSS THE OHIO
VALLEY. WIND SPEEDS WILL DEPEND UPON HOW FAR NORTH THE LOW TRACKS.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MULLEN
NEAR TERM...TK/MULLEN
SHORT TERM...MULLEN
LONG TERM...SEFCOVIC
AVIATION...ADAMS
MARINE...SEFCOVIC
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
516 AM EDT TUE APR 26 2016
.SYNOPSIS...
LOW PRESSURE OVER SOUTHERN MICHIGAN WILL MOVE EAST AND TRACK
OVER NRN PA/WRN NY STATE TODAY. THIS LOW WILL PUSH A COLD FRONT
THROUGH THE AREA TODAY. A LARGE AREA OF HIGH PRESSURE OVER SOUTH
CENTRAL CANADA WILL RIDGE SOUTHEAST ACROSS THE GREAT LAKES AND
INTO PENNSYLVANIA WEDNESDAY INTO THURSDAY WITH FAIR AND COOLER
CONDITIONS. ANOTHER AREA OF LOW PRESSURE TRACK SOUTH OF
PENNSYLVANIA THURSDAY INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SUBSTANTIALLY WEAKENED MCS HEADED ACROSS NRN OHIO AND LAKE ERIE AT
09Z WILL PUSH A PRECEDING OUTFLOW BOUNDARY ACROSS NRN AND WESTERN
PENN THIS MORNING...MUDDYING THE LOCATION OF PREVIOUS OUTFLOW
BOUNDARIES AND THE TRUE STATIONARY FRONT NEAR THE PA/NY BORDER
EARLY TODAY.
DECENT AMOUNT OF MORNING SUNSHINE (MIXED WITH SOME ALTO CU CLOUDS)
AND INCREASING DEWPOINTS/MID LEVEL WESTERLY WINDS OVER SOUTHERN
PENN WILL SET THE STAGE FOR SCATTERED/POTENTIALLY STRONG TO
SEVERE TSRA LATE THIS MORNING...OR MORE LIKELY DURING THE EARLY TO
MID AFTERNOON HOURS.
TEMPS FOR THE REST OF THE PREDAWN HOURS WILL STAY QUITE MILD...IN
THE 50S...TO LOWER AND MID 60S ACROSS THE LAUREL HIGHLANDS.
WINDS WILL BE GENERALLY LIGHT AND VARIABLE...BUT SOME 15 TO 25 KT
GUSTS ARE POSSIBLE INVOF SCATTERED HEAVIER SHOWERS OVER NRN
PENN...AND ACCOMPANYING THE MCS OUTFLOW BOUNDARY AS IT PUSHES SE
FROM THE NW MTNS OF PENN.
SFC FRONTAL WAVE TRACKS ALONG THE PA/NY BORDER THIS MORNING...
BEFORE SAGGING SOUTHWARD AS COLD FRONT SETTLES ACROSS THE
COMMONWEALTH.
CONVECTION SHOULD STEADILY EXPAND FROM NW TO SE ACROSS THE CWA AS
MILDER AND MORE UNSTABLE AIR PUSHES NE OUT OF THE OHIO VALLEY. A
2-3 SIGMA 850MB WESTERLY JET WILL SLIDE ACROSS THE SOUTHERN HALF
OF PENN THROUGH THE MIDDAY HOURS...AND WILL SUPPORT AN INITIALLY
COMPACT AREA OF 3-4 SIGMA 850 MB MOISTURE FLUX. THIS AREA OF
BETTER MOISTURE AND STRONGER FORCING ALONG AND AHEAD OF THE
OUTFLOW BOUNDARY AND SFC CFRONT WILL COVER ABOUT THE SE THIRD OF
THE STATE AT 18Z.
THE AFOREMENTIONED OUTFLOW BOUNDARY WILL SERVE AS THE DEMARCATION
LINE BETWEEN MDTLY HIGH ML CAPES DURING THE LATE MORNING AND
AFTERNOON HOURS...AND MUCH MORE STABLE AIR ACROSS THE NRN MTNS.
SPC`S DAY 1 MARGINAL RISK AREA COVERS THE SE HALF OF PENN...BUT
UPGRADED FAR SERN PENN (INCLUDING YORK AND LANCASTER COUNTIES) TO
A SLIGHT RISK WITH THE MAIN SEVERE WEATHER THREAT COMING IN THE
FORM OF ISOLATED STRONG/DAMAGING WESTERLY WIND GUSTS ATTRIBUTED TO
30-50 KT WINDS IN THE 850-700 MB LAYER...AND AN INVERTED-V
SOUNDING. MODELS SHOWING LOCAL PREFRONTAL 1000 J/KG CAPES ALONG
THE MASON-DIXON LINE LATER THIS MORNING/AFTN.
TOTAL FCST RAINFALL FROM ABOUT MIDNIGHT MONDAY NIGHT THROUGH 6 PM
TODAY WAS PAINTED TO BE A BIT HIGHER THAN A GEFS/SREF
BLEND ACROSS APPROX THE SOUTHERN HALF OF THE CWA...GIVEN THE 6
HOURLY TOTALS THAT OCCURRED WITH THE MCS NOW TRACKING ACROSS
WESTERN LAKE ERIE AND FAR NWRN OHIO.
COOL AIR REACHES THE NORTHWEST BY LATE THIS MORNING...WITH HIGHS
THERE ONLY REACHING NEAR 60F. FARTHER SOUTH ANOTHER WARM DAY WILL
BE SEEN WITH HIGHS IN THE MID TO UPPER 70S FOR ONE MORE DAY ACROSS
SOUTH CENTRAL AND SOUTHEAST PA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
LATEST...07Z HRRR IMPLIES THAT THE SFC COLD FRONT WILL SLIDE
SOUTH OF THE I-76/78 CORRIDOR BEFORE DUSK...WITH LINGERING
SHOWERS AND TSRA NEAR THE MASON/DIXON LINE INTO THIS EVENING.
A SEVERAL HOUR PERIOD OF BKN-OVC STRATUS AND STRATO CU SHOULD
FOLLOW THE CFROPA THROUGH LATE THIS EVENING...BEFORE DRIER AIR
PUSHES IN FROM THE NORTH/NORTHEAST AND HELPS TO ERODE THE LOW CLOUD
DECK.
LOW TEMPS TONIGHT WILL RANGE FROM THE FROSTY LOWER 30S ACROSS THE
NORTHERN TIER COUNTIES...TO THE MID AND UPPER 40S IN THE SOUTH.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
WED LOOKS DRY AND COOLER...AS A NE FLOW OF DRY AIR BUILDS
SOUTHWARD FROM A LARGE HIGH OVER WESTERN HUDSON BAY.
A SYSTEM TRACKING SOUTH OF THE AREA ON THU WILL BRING SOME
RAIN...AND MORE NOTABLY COOLER TEMPERATURES TO THE AREA.
A SECOND WEAK SYSTEM TRACKING SOUTH OF THE AREA OUT OF WV MAY
BRING SOME SHOWERS STILL ON FRIDAY. LEFT POPS IN.
STILL SOME HINTS OF A JET MAX DROPPING SE ON SAT...BUT REALLY
NO MOISTURE TO WORK WITH. THUS STILL EXPECT THE DAY TO BE DRY.
MID SHIFT HAD SOME SHOWERS IN FOR LATER ON SUNDAY. YESTERDAY THE
EC WAS TOO FAST...STILL THAT WAY TODAY. LEFT POPS IN BUT DID LOWER
SOME FOR SUNDAY AND SUNDAY NIGHT.
FOR SUNDAY NIGHT..DID EDGE TEMPERATURES DOWN A LITTLE.
LOOKS WET AND COOL FOR MONDAY. DID NOT GO QUITE AS HIGH AS
THE SUPERBLEND WITH THE POPS.
CLEARING OUT LATER MONDAY NIGHT.
OVERALL A PATTERN THAT FAVORS WETTER AND COOLER WEATHER
THAN WE HAVE HAD LATELY.
&&
.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
SFC FRONTAL WAVE TRACKS ALONG THE PA/NY BORDER THIS MORNING...
BEFORE SAGGING SOUTHWARD AS COLD FRONT SETTLES ACROSS THE
COMMONWEALTH LATER IN THE DAY.
OVERNIGHT...GENERALLY VFR CONDITIONS PERSISTING AREAWIDE...EXCEPT
IN SCT SHOWERS/VERY ISOLATED TSTMS MAINLY NORTH OF I-80. MORE
WIDESPREAD SHOWERS WILL IMPACT NW PORTIONS AFTER 09Z AS WESTERLY LLJET
SWINGS THROUGH.
EXPECT A BIT OF A MINIMUM OF SHOWER ACTIVITY MID/LATE
MORNING...BUT CONVECTION SHOULD STEADILY EXPAND OVER CENTRAL MTNS
AND EXPAND INTO SOUTHERN MTNS IN THE AFTERNOON AS MORE UNSTABLE
AIR PUSHES NE OUT OF THE OHIO VALLEY.
PRECIP WILL END FROM NW TO SE...EXITING THE LOWER SUSQ SHORTLY
AFTER 00Z WED. LOWERING CIGS WILL SAG IN FROM THE
NORTH...IMPACTING MAINLY WESTERN HIGHER TERRAIN AND LIKELY
EXPANDING INTO THE CENTRAL MTNS TUE NIGHT.
OUTLOOK...
WED...NO SIG WX EXPECTED.
THU-FRI...MVFR WITH SHRA LIKELY.
SAT...FAIR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/MARTIN
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
308 AM CDT TUE APR 26 2016
.DISCUSSION...
SKIES WERE GENERALLY CLEAR ACROSS THE MIDSOUTH WITH PATCHY
STRATOCU IN NORTH CENTRAL ARKANSAS STARTING TO BLEED INTO THE
WESTERN COUNTIES. TEMPERATURES WERE IN THE 60S WITH SOUTH WINDS
RUNNING 5 TO 10 MPH. THOUGH THE MIDSOUTH WAS FREE OF
CONVECTION...STORMS NEAR THE KANSAS CITY METRO ALONG A STATIONARY
FRONT ARE FORMING AHEAD OF SCHEDULE COMPARED TO THE HRRR MODEL.
FOR TODAY AND TOMORROW...BREEZY SOUTH WINDS AHEAD OF A DEVELOPING
STORM IN THE PLAINS WILL CONTINUE TO PUMP GULF MOISTURE INTO THE
MIDSOUTH...WITH DEWPOINTS CLIMBING INTO THE MID AND UPPER 60S BY
THIS AFTERNOON. THIS COUPLED WITH TEMPERATURES IN THE LOW TO MID
80S WILL GENERATE A FAIR AMOUNT OF CUMULUS AND CAPE VALUES NEAR
3000 J/KG. HOWEVER THE CLOSEST TRIGGER TO INITIATE STORMS WILL
LIE WITH HOW THE ABOVE MENTIONED CONVECTION IN MISSOURI UNFOLDS.
HRRR AND NAM MODELS SUGGEST THIS ACTIVITY WILL PROPAGATE EAST
SOUTHEAST ALONG THE FRONT AS IT PUSHES INTO THE LOWER OHIO VALLEY.
A STRONG ENOUGH AND PERSISTENT ENOUGH OUTFLOW FROM THIS MCS COULD
FIRE STORMS LATE THIS AFTERNOON AND EVENING ALONG THE FAR NORTHERN
MIDSOUTH COUNTIES...OF WHICH SOME COULD BE STRONG OR SEVERE GIVEN
THE ANTICIPATED CAPE. FOR NOW WILL PASS THE POTENTIAL ON TO THE
DAYCREW. BETTER CHANCES FOR STORMS WILL ARRIVE LATER TONIGHT AS
CONVECTION MARCHES EAST OUT OF OKLAHOMA AND TEXAS. THIS ACTIVITY
MAY ALSO MAINTAIN A FAIR AMOUNT OF INTENSITY AS IT WILL BE LINKED
TO THE SUPPORTING NEGATIVE TILTED SHORTWAVE. MODELS SHOW THE
LEADING EDGE REACHING THE MISSISSIPPI RIVER NEAR DAYBREAK AND THE
TENNESSEE RIVER BY NOON. AFTER WHICH QUESTIONS ARISE WITH THE
AMOUNT OF LINGERING CLOUD COVER AND THUS THE ABILITY FOR THE
ATMOSPHERE TO SOMEWHAT RELOAD. MODELS SHOW A WEAKER WAVE SWINGING
THROUGH THE OZARKS IN THE 26/0Z TO 26/06Z TIME FRAME THAT MAY BE
ENOUGH FOR AT LEAST ISOLATED STORMS FROM LATE IN THE AFTERNOON
THROUGH THE EVENING. LOW LEVEL SHEAR WILL HAVE WEAKEN ATT...ALONG
WITH RISING HEIGHT FALLS...AS BOTH THE UPPER AND LOW LEVEL SYSTEM
BEGIN FILLING. THE ONLY CAVEAT WILL BE MIDLEVEL LAPSE RATES WILL
FALL TO NEAR 8C...WHICH WOULD LEAD TO A LARGE HAIL THREAT. CHANCES
FOR RAIN WILL DIMINISH FROM WEST TO EAST LATE TOMORROW NIGHT.
HIGHS TODAY WILL BE IN THE LOW TO MID 80S WITH TEMPERATURES
RUNNING ABOUT FIVE DEGREES COOLER TOMORROW. LOWS IN THE 60S.
THURSDAY AND FRIDAY...DRY INITIALLY WITH WEAK LOW LEVEL FLOW AND
A CONTINUANCE OF ABOVE NORMAL TEMPERATURES. A SECOND STORM SYSTEM
WILL DEVELOP IN THE SOUTHERN ROCKIES...SURGING MOISTURE AND
ENERGY BACK INTO THE OZARKS AND LOWER MISSISSIPPI VALLEY BY FRIDAY
AFTERNOON. SHOWERS AND STORMS WILL OVERSPREAD THE AREA FRIDAY NIGHT.
SATURDAY THROUGH MONDAY NIGHT...A GENERALLY WET PERIOD AS THE
UPPER LOW IN THE FOUR CORNERS TAKES A SIMILAR TRACK...AND TIMING
AS THE CURRENT FRONT RANGE LOW. THIS WOULD PLACE THE MAIN JET
CORRIDOR FROM TEXAS TO THE OHIO VALLEY. ROUNDS OF
CONVECTION...WITH SOME STORMS POTENTIALLY SEVERE APPEAR
FAVORABLE...AS WELL AS A THREAT FOR PERIODS OF HEAVIER RAINFALL.
HIGH TEMPERATURES WILL RUN CLOSE TO NORMAL WITH ABOVE NORMAL LOWS.
JAB
&&
.AVIATION...
06Z TAF CYCLE
VFR CONDS ONGOING WILL PERSIST THE ENTIRE CYCLE. SOUTHERLY WINDS
WILL PICK UP AFTER SUNRISE TO BE SUSTAINED BETWEEN 8 AND 10 KTS
FOR TUESDAY AFTERNOON. HIGHER GUSTS ARE LIKELY AT KMEM AND KJBR
AS SFC RETURN FLOW INCREASES AHEAD OF A DEVELOPING LOW PRESSURE
SYSTEM TO THE WEST AND ASSOCIATED COLD FRONT. WINDS SUBSIDE
SLIGHTLY AFTER SUNSET.
ZDM
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1145 PM CDT MON APR 25 2016
.AVIATION...
UPPER LOW STILL ON TRACK TO MOVE FROM SOUTHERN UTAH AT MIDNIGHT TO
SOUTHEAST COLORADO TUESDAY EVENING. THIS WILL DEEPEN THE SURFACE
LOW PRESSURE TROUGH ACROSS THE OKLAHOMA AND TEXAS PANHANDLES DRIVING
SUSTAINED WINDS AROUND 25 TO 30 KNOTS ACROSS THE TERMINALS. RECENT
SOLUTIONS HAVE SLIGHTLY STRENGTHENED THIS SYSTEM COMPARED TO
PREVIOUS RUNS WITH HIGHER WINDS REFLECTED IN TAF FORECASTS AS
WELL. SURFACE WINDS WILL VEER MORE SOUTHWESTERLY OVERNIGHT KLBB
AND KPVW ESPECIALLY. STILL CANNOT RULE OUT STRATUS DECK NEARING
KCDS EARLY TUESDAY MORNING THOUGH SOLUTIONS STILL DO NOT SHOW THIS
LAYER MOVING AS FAR WEST AS KCDS. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 636 PM CDT MON APR 25 2016/
AVIATION...
SOUTHWEST FLOW WILL STRENGTHEN NOTABLY IN THE COMING 24 HOURS AS A
DEEP UPPER LOW OVER THE EASTERN GREAT BASIN THIS EVENING MOVES TO THE
CENTRAL HIGH PLAINS LATE TUESDAY. ADDED A PERIOD AROUND MIDDAY FOR
KLBB AND KPVW FOR A SHARP INCREASE IN WIND SPEEDS AT THAT TIME
WITH MINOR VISIBILITY RESTRICTION AS WELL. WILL ADDRESS KCDS WIND
ISSUES FOR THE 06Z PACKAGE. TONIGHT WE EXPECT A WEAK UPPER IMPULSE
CURRENTLY CROSSING NORTHERN CHIHUAHUA MEXICO TO MOVE ACROSS OUR
SOUTHEAST ZONES EARLY TUESDAY. APPEARS RAP AND HRRR SOLUTIONS MAY
BE OVERDOING FORECAST THUNDERSTORMS LATE TONIGHT SINCE WE ARE
SEEING LITTLE TO NOTHING DEVELOPING TO OUR SOUTHWEST AT THIS TIME.
BUT WILL KEEP A CLOSE EYE AS THE EVENING PROGRESSES. ALSO WATCHING
FOR DRY-LINE RETREAT INTO THE ROLLING PLAINS TONIGHT BEFORE LOW
LEVEL FLOW VEERS LATER TUESDAY MORNING. OUTSIDE CHANCE STILL OF
STRATUS AS FAR WEST AS KCDS SO WILL RETAIN THE PREVIOUS MENTION OF
FEW020 AT KCDS. RMCQUEEN
PREV DISCUSSION... /ISSUED 336 PM CDT MON APR 25 2016/
SHORT TERM...
THE DRYLINE HAS MOVED EAST OF THE FORECAST AREA MONDAY AFTERNOON
WITH TEMPERATURES IN THE MID TO UPPER 80S...AND A FEW LOWER
90S...BEING REPORTED AREA-WIDE AT 3 PM. OFF TO OUR WEST...WATER
VAPOR IMAGERY SHOWS A LARGE TROUGH ACROSS THE DESERT SOUTHWEST.
LOWER AND MID-LEVEL FLOW IS FORECAST TO ONLY BACK SLIGHTLY TONIGHT
AS THE TROUGH APPROACHES BUT THIS WILL LIKELY BE ENOUGH TO DRAW THE
DRYLINE BACK WEST INTO THE SOUTHERN AND EASTERN ROLLING PLAINS. SOME
LOW STRATUS WILL BE POSSIBLE IN THAT AREA EARLY TUESDAY
MORNING...BUT CONFIDENCE IS LOW.
THE DRYLINE WILL RACE EAST ON TUESDAY AS A STRONG UPPER-LEVEL JET
EMERGES OVER WEST TEXAS. A DRY AND DEEPLY MIXED AIRMASS WILL SPREAD
ACROSS OUR FORECAST AREA WITH GUSTY SOUTHWEST TO WEST WINDS
DEVELOPING IN THE AFTERNOON. WE ARE STILL EXPECTING BREEZY TO WINDY
CONDITIONS ON THE CAPROCK WITH SPEEDS GENERALLY IN THE 25 TO 35 MPH
RANGE...WITH GUSTS WELL INTO THE 40S...AND PERHAPS SLIGHTLY HIGHER
ROUGHLY TO THE WEST OF INTERSTATE 27/HIGHWAY 87. SOME PATCHY BLOWING
DUST APPEARS LIKELY AS MAY FIELDS ACROSS THE AREA ARE BEING PLOWED
FOR SPRING PLANTING. COLD ADVECTION WILL SPREAD IN FROM THE WEST BY
AFTERNOON AND TEMPS ARE LIKELY TO BE COOLER ON THE CAPROCK...WITH
HIGHS IN THE 70S TO LOW 80S...AND MID TO UPPER 80S IN THE ROLLING
PLAINS.
LONG TERM...
TUE NIGHT/WED...UPPER LOW WILL CONTINUE LIFTING INTO CENTRAL PLAINS
LATE TUE INTO WED. DRY AIR WILL CONT IN PLACE WITH SURFACE GRADIENT
WEAKENING DURING THE AFTERNOON RESULTING IN MODERATE WLY WINDS
DECREASING AFTER 21Z. DRYLINE WILL REMAIN WELL EAST OF THE REGION IN
WRN OK AND NW TEXAS. MINIMAL FORCING AS WEAK DOWNSTREAM RIDGING AND
WARMING MID LEVEL TEMPS KEEP SFC TEMPS WARM AND CLOUD COVER TO
MINIMUM.
WED NIGHT/THURSDAY...A RETREATING DRY LINE AND INCREASING FLOW ALOFT
WILL MATERIALIZE AS UPPER LOW TRANSLATES EWD TO CENTRAL AZ WITH
ENERGETIC UPR TROUGH APPROACHING W TX. WEAK FRONT LOOKS TO PUSH
SOUTHWARD INTO PANHANDLE TOWARD 12Z THUR. TOO EARLY TO DETERMINE
WHERE THIS BOUNDARY WILL SET UP AFTER A POSSIBLE NORTHWARD RETREAT
IN THE AFTERNOON. BACKING LOW LEVEL FLOW WILL TRANSPORT SOME GULF
MOISTURE AT LEAST INTO ROLLING PLAINS AND PERHAPS FARTHER WEST.
SEVERE STORMS CERTAINLY LOOK POSSIBLE ESPECIALLY NEAR TRIPLE
POINT...BUT THAT COULD BE FARTHER NORTH OR NE OF FA...AND ATMOSPHERE
MAY BE SOMEWHAT CAPPED FARTHER SOUTH WITH MORE LIMITED COVERAGE.
CERTAINLY RISK OF SEVERE THURSDAY.
BY LATE THURSDAY...IF TIMING OF GFS/ECM IS TO BE BELIEVED...LOW
CLOUDS/HIGHER DEWPOINTS LIKELY TO RETURN WWD INTO EARLY FRIDAY WITH
HIGHER COVERAGE OF SHOWERS/SOME THUNDER POSSIBLE OVERNIGHT WITH
MODERATE FORCING ALOFT. DRYLINE EXPECTED TO RAPIDLY SURGE EAST AS
STRONGEST UPPER LEVEL WINDS WITH TROF MOVE ACROSS AREA FRIDAY
AFTERNOON. COULD SEE SOME ACTIVITY EARLY...BUT DRYLINE MAY BE EAST
OF THE REGION BY LATE AFTERNOON FRI. EXTREME ERN COUNTIES MOST
LIKELY TO HAVE A CONDITIONAL SEVERE CHANCE THEN.
WEEKEND INTO EARLY NEXT WEEK...ELONGATED UPPER TROUGH WILL STRETCH
ACROSS THE WESTERN CONUS SATURDAY WITH WESTERLY FLOW ALOFT ACROSS
THE AREA WITH DRY WEATHER ANTICIPATED AT THIS TIME. ANOTHER FRONT
COULD ENTER THE PICTURE LATE SATURDAY OR ON SUNDAY...WITH MODELS NOT
OVERLY EXCITED ABOUT RAIN COVERAGE. NEXT LOW ATTM WILL DIG INTO
SRN AZ WITH BRIEF DOWNSTREAM RIDGING LIKELY LATE SUNDAY. BY SUNDAY
NIGHT...UPPER HEIGHT FIELD WOULD SUGGEST MODERATE/STRONG FORCING
IN EASTERN NEW MEXICO WITH DIFLUENT NEG TILTED UPR TROF
APPROACHING WITHIN LARGE SCALE REX BLOCK/SPLIT FLOW PATTERN ACROSS
WRN/CNTRL US. COOL NE SURFACE FLOW CONTG WITH CLOUDY...COOL
WEATHER. PRECIPITATION COULD BECOME WIDESPREAD EARLY NEXT WEEK IN
POST FRONTAL ENVIRONMENT WITH SW FLOW ALOFT ABOVE SFC HIGH
PRESSURE RIDGE...KEEPING CHANCE OF RAIN IN FCST ALONG WITH
POTENTIALLY MUCH COOLER TEMPS.
FIRE WEATHER...
DESPITE THE COOLER TEMPS...NEAR SEASONAL NORMS FOR LATE APRIL...A
VERY DRY AIRMASS WILL RESULT IN RH VALUES FALLING INTO THE SINGLE
DIGITS ACROSS THE WESTERN SOUTH PLAINS AND FAR SOUTHWEST TEXAS
PANHANDLE TUESDAY AFTERNOON. COMBINED WITH GUSTY S-SW WINDS...THIS
WILL RESULT IN A PERIOD OF METEOROLOGICAL CRITICAL CONDITIONS.
HOWEVER...THE RECENT GREEN-UP OF GRASSES...REFLECTED IN LOW ERC
VALUES...MEANS THAT FUELS ARE NOT PARTICULARLY RESPONSIVE TO FIRE
STARTS. ERC VALUES HAVE TRENDED HIGHER THOUGH DUE TO THE RECENT DRY
WEATHER. WE WILL HOLD OFF ON ANY FIRE DANGER HIGHLIGHTS AT THIS TIME
GIVEN THE STATE OF THE FUELS...BUT A FIRE DANGER STATEMENT MAY BE
ISSUED FOR THE SITUATION TUESDAY.
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/05
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
414 AM EDT TUE APR 26 2016
.SYNOPSIS...
FRONT WITH WAVES OF LOW PRESSURE EXTENDED FROM NEW JERSEY TO
MISSOURI THIS MORNING. THIS FRONT WILL DRIFT SOUTH THEN STALL OVER
THE MID ATLANTIC REGION ON WEDNESDAY. ANOTHER LOW PRESSURE SYSTEM
WILL TRACK FROM THE MID MISSISSIPPI VALLEY TO THE EAST COAST ON
THURSDAY AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 355 AM EDT TUESDAY...
LOW PRESSURE OVER MICHIGAN WILL MOVE EAST ALONG A FRONT INTO
EASTERN PENNSYLVANIA TODAY. THEN THE FRONT WILL MOVE SOUTH INTO
THE MID ATLANTIC REGION LATE TODAY INTO TONIGHT. THE SURFACE
BOUNDARY REACHES THE FORECAST AREA AFTER 00Z/8PM...WHILE THE
850MB FRONT STAYS WELL TO THE NORTH. STARTING OUT WITH LITTLE
CLOUD COVER THIS MORNING SO TEMPERATURES WILL WARM QUICKLY AFTER
SUNRISE. WITH SURFACE DEW POINTS IN THE 50S...CONVECTIVE AVAILABLE
POTENTIAL ENERGY WAS FORECAST TO BE AROUND 1500 J/KG THIS
AFTERNOON AHEAD OF THE FRONT. SOME GUIDANCE SUGGESTED POOLING OF
DEW POINTS IN THE LOWER 60S JUST AHEAD OF THE BOUNDARY WHICH WOULD
RESULT IN EVEN LARGER CAPE. 00Z NAM AS WELL AS THE RAP AND LOCAL
WRF HAVE A BULK OF THE PRECIPITATION THAT WILL BE AHEAD OF THE
FRONT REACHING THE NORTHERN COUNTY WARNING AREA JUST AFTER
18Z/2PM. BETTER COVERAGE OF SHOWERS AND THUNDERSTORMS MAY NOT
PROGRESS SOUTH...REACHING THE VIRGINIA/NORTH CAROLINA BORDER UNTIL
AROUND 00Z/8PM. BETTER VORTICITY ADVECTION AND JET SUPPORT REACH
THE FORECAST AREA TONIGHT SO HAVE INCREASED THE PROBABILITY OF
PRECIPITATION FOR TONIGHT.
GUIDANCE WAS TOO COOL FOR MAXIMUM TEMPERATURES ON MONDAY. HAVE
GONE CLOSER TO WARMER GUIDANCE AND PERSISTENCE FROM MONDAY FOR
MAXIMUM TEMPERATURES TODAY. CLOUDS AND MILD DEW POINTS WILL KEEP
TEMPERATURES FROM DROPPING MUCH OVERNIGHT. HAVE RAISED MINIMUM
TEMPERATURES SLIGHTLY ACROSS THE PIEDMONT TONIGHT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
AS OF 330 AM EDT TUESDAY...
THE UPPER LEVEL PATTERN WILL REMAIN UNSETTLED AS THE WESTERN TROF
SPLINTERS INTO PIECES WITH SEVERAL BITS OF SHORT WAVE ENERGY MOVING IN
OUR DIRECTION INTERSPERSED WITH PERIODS OF GENERALLY FLAT RIDGING. AND
WITHOUT SOLID UPPER LEVEL SUPPORT TO MOVE IT ALONG...THE FRONTAL ZONE
AT THE SURFACE WILL SIMPLY LINGER OVER THE REGION THROUGH THE END OF
THE WEEK. AMPLE CONVERGENCE AND INSTABILITY IN THE FRONTAL ZONE WILL
KEEP UP WITH A CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY. BY FRIDAY
IT APPEARS THAT A SHORT WAVE REMNANT OF THE WESTERN TROF WILL SWING BY
TO OUR NORTH AND HELP PUSH THE FRONTAL BOUNDARY FURTHER TO THE SOUTH
AND ALLOW A WEDGE OF HIGH PRESSURE TO BUILD DOWN EAST OF THE
APPALACHIANS. HOWEVER ANY IMPROVEMENT IN OUR WEATHER LOOK TO BE
MARGINAL SINCE CLOUDS AND SOME LIGHT PRECIPITATION WILL ACCOMPANY THE
WEDGE. TEMPERATURES WILL GENERALLY BE A BIT ABOVE NORMAL THROUGH THE
END OF THE WEEK WITH HIGHS IN THE MID 70S TO AROUND 80 EAST OF THE BLUE
RIDGE...AND IN THE LOW TO MID 70S WEST.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 245 PM EDT MONDAY...
WEAK UPPER RIDGING THROUGH SATURDAY WILL KEEP PRECIP CHANCES CONFINED
TO ISOLATED/WIDELY SCATTERED IN COVERAGE. AT THE SFC...12Z ECMWF KEEPS
WEDGE IN PLACE THROUGH SATURDAY. WHILE TEMPS WERE BROUGHT DOWN A COUPLE
OF DEGREES DURING THIS TIME...THESE FORECAST VALUES STILL MAY BE TOO
WARM.
HOWEVER...BETTER CHANCES FOR MORE WIDESPREAD PRECIPITATION
ARRIVE LATER SUNDAY INTO MONDAY...DEPENDING ON THE ARRIVAL OF AN
OPENING UPPER LOW MOVING THROUGH THE OHIO VALLEY. AS IT TYPICAL
FOR THE LONG RANGE MODELS...THERE IS DISAGREEMENT IN THE TIMING
AND TRACK OF THIS SYSTEM...BUT INDIVIDUAL GEFS ENSEMBLE MEMBERS
SUGGEST THE BEST CHANCES FOR PRECIPITATION WILL BE LATE SUNDAY
INTO EARLY MONDAY...AND THIS IS THE TIME PERIOD WHERE THE POPS ARE
HIGHEST.
TEMPS ARE EXPECTED TO BE BELOW NORMAL EARLY WITH THE WEDGE IN
PLACE TO NEAR NORMAL LATER IN THE LONG TERM PERIOD.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
AS OF 130 AM EDT TUESDAY...
A COLD FRONT EXTENDED FROM RHODE ISLAND TO MICHIGAN TO MISSOURI
EARLY THIS MORNING. THIS FRONT WILL MOVE SOUTH INTO THE MID
ATLANTIC REGION TODAY. WITH THE BOUNDARY IN THE AREA AND
MOISTURE ON THE INCREASE...SCATTERED SHOWERS AND THUNDERSTORM WITH
MVFR CEILINGS AND VISIBILITIES ARE EXPECTED THIS
AFTERNOON...MAINLY ACROSS THE MOUNTAINS. BY THE LATE MORNING
SURFACE WIND GUSTS WILL BE IN THE 15 TO 20 KT RANGE. MODELS BRING
THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS INTO THE AREA AFTER
3PM IN KLWB AND NOT UNTIL 5PM AT KDAN. MEDIUM CONFIDENCE ON THE
TIMING OF THE PRECIPITATION.
EXTENDED AVIATION DISCUSSION...
THIS FRONT WILL REMAIN STALLED OVERHEAD TUESDAY NIGHT AND
WEDNESDAY...BEFORE A STRONGER COLD FRONT ENTERS FROM THE WEST TO
PUSH THE WEAKER FRONT OFFSHORE. DURING THIS TIME...SCATTERED
SHOWERS WITH A FEW AFTERNOON THUNDERSTORMS APPEAR LIKELY. THE
GREATEST CHANCE OF RAIN AND MVFR/IFR CONDITIONS WILL ACCOMPANY THE
STRONGER COLD FRONT ON THURSDAY. SOME CLEARING SHOULD TAKE PLACE
DURING FRIDAY...ALTHOUGH A FEW MOUNTAIN SHOWERS AND MVFR CLOUDS
ARE POSSIBLE.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...PH
LONG TERM...PH
AVIATION...AMS/DS
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1032 AM EDT TUE APR 26 2016
.SYNOPSIS...
A FRONTAL BOUNDARY LOCATED TO OUR NORTH WILL SLOWLY PUSH
SOUTHWARD ACROSS THE AREA TODAY AS AN AREA OF LOW PRESSURE MOVES
ALONG THE BOUNDARY. THE FRONT WILL PUSH SOUTH OF THE AREA
OVERNIGHT INTO WEDNESDAY MORNING AND STALL TO OUR SOUTH. ANOTHER
AREA OF LOW PRESSURE WILL MOVE ALONG THIS BOUNDARY TO OUR SOUTH
LATE THURSDAY INTO THURSDAY NIGHT. OUR AREA WILL REMAIN ON THE
SOUTHERN EDGE OF HIGH PRESSURE CENTERED ACROSS CENTRAL CANADA OVER
THE WEEKEND. AN AREA OF LOW PRESSURE AND ASSOCIATED FRONTAL
BOUNDARIES MAY AFFECT THE AREA EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
13Z SURFACE ANALYSIS SHOWS A QUASI-STATIONARY FRONT ALONG THE NY-
PA, ARCING E-SEWD INTO THE NRN NJ. A WEAK AREA OF LOW PRESSURE
WAS NOTED ALONG THIS BOUNDARY NEAR BGM. LOOKING ALOFT, WATER VAPOR
SATELLITE IMAGERY SHOWS A SHORTWAVE TROUGH ASSOCIATED WITH THE
REMNANTS OF A MIDWEST MCS IS MOVING INTO E PA MID MORNING.
WEAKENING TRENDS WITH REGARDS TO THE CONVECTION CONTINUE TO BE
NOTED IN THE IR SATELLITE/ MOSAIC RADAR LOOP AS THIS SYSTEM MOVES
EASTWARD INTO OUR AREA THIS MORNING. THESE SHOWERS WILL MOVE THRU
THE SRN POCONOS AND NW NJ OVER OVER THE NEXT 1-2 HOURS. ELSEWHERE,
VIRTUALLY REMOVED THE MENTION OF PRECIP FROM THE FORECAST THRU
MIDDAY (THOUGH ISO SHOWERS WERE KEPT IN A FEW LOCATIONS AREAS).
LEFTOVER DEBRIS CLOUDS FROM THE REMNANT MCS WILL SWEEP THRU THE
AREA WHICH WILL DELAY STRONG SOLAR HEATING BY 2 OR 3 HOURS. MADE
ONLY SLIGHT MODIFICATIONS TO MAX TEMPS TODAY, TRYING TO SHOW A
TIGHT N-S TEMPERATURE GRADIENT ALONG THE I-80 CORRIDOR SINCE THIS
IS WHERE THE FRONT HAS STALLED. WE WERE CONSERVATIVE IN MAKING
UPWARD ADJUSTMENTS FOR HIGHS IN THE WARM SECTOR DUE TO THE MORNING
CLOUDS BUT HIGHS IN THE MID TO UPPER 80S ARE NOT OUT OF THE
QUESTION FROM PHILA SOUTHWARD IF WE CAN SEE AN EXTENDED PERIOD OF
SUNSHINE DURING PEAK HEATING THIS AFTERNOON.
BASED ON THE LATEST HI-RES CONVECTIVE-ALLOWING MODELS, HOURLY
POPS/WX WERE UPDATED FOR THIS AFTERNOON TO BETTER TIME THE
CONVECTION THAT IS EXPECTED TO DEVELOP ALONG THE FRONT AS IT
PROGRESSES SWD THRU THE AREA. FORECAST SOUNDINGS FROM THE NAM 4KM,
RAP AND HRRR SHOW MODEST INSTABILITY WITH ABOUT 600-1000 J/KG OF
MLCAPE DEVELOPING FROM SE PA-C NJ AND POINTS SWD BY MID TO LATE
AFTERNOON. FORECAST BULK SHEAR PROFILES INCREASE TO NEAR 50 KT
LATE THIS AFTERNOON AS A 65 KT MID-LEVEL JET STREAK SHIFTS
OVERHEAD. LARGER-SCALE LIFT DOES NOT LOOK QUITE AS FAVORABLE AS
IT ONCE DID IN EARLIER MODEL RUNS WITH THE DEEPEST LIFT FROM AN
APPROACHING MID-LEVEL SHORTWAVE TROUGH AND UPPER-LEVEL JET STREAK
SLIGHTLY REMOVED NORTH (ACROSS FAR NORTHERN PARTS OF THE CWA)
FROM WHERE THE STRONGEST DESTABILIZATION IS EXPECTED TO OCCUR THIS
AFTERNOON (ACROSS THE SOUTHERN HALF OF THE CWA). NONETHELESS,
THERE IS STILL ENOUGH INGREDIENTS AVAILABLE FOR AT LEAST SEVERAL
SEVERE THUNDERSTORMS TO DEVELOP. THE MAIN THREAT IS DAMAGING
WINDS BUT ISOLATED LARGE HAIL IS POSSIBLE. THE LATEST SPC D1
FORECAST EXPANDED THE SLIGHT RISK INTO MOST OF THE FORECAST AREA.
THE GREATEST RISK FOR SEVERE STORMS APPEARS TO BE FROM ABOUT 2-5
PM IN NE PA/NW NJ, 4-7 PM IN SE PA AND S NJ, 5-9 PM IN THE
DELMARVA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
THE COLD FRONT IS EXPECTED TO EXTEND THROUGH THE PHILADELPHIA
METROPOLITAN AREA AROUND 800 PM AND IT SHOULD REACH SOUTHERN
DELAWARE AND ITS ADJACENT COASTAL WATERS BY MIDNIGHT. THE ARRIVAL
OF THE FRONT SHOULD BRING AN END TO THE PRECIPITATION. HOWEVER,
CLOUDS ARE ANTICIPATED TO LINGER THROUGH MUCH OF THE NIGHT.
THE WIND SHOULD SETTLE INTO THE NORTH AND NORTHEAST BEHIND THE
COLD FRONT. TEMPERATURES ARE FORECAST TO DROP INTO THE 40S AND
50S.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
THE COLD FRONT WILL BECOME STATIONARY NEAR THE NC-VA BORDER
WEDNESDAY. DRIER AND COOLER AIR WILL WORKS ITS WAY INTO THE REGION
AS CANADIAN HIGH PRESSURE CENTERED NEAR THE NORTHWEST PASSAGES
RIDGES DOWN TOWARD US. HOWEVER, THE DRIER AIR MAY STRUGGLE TO MAKE
IT INTO OUR FAR SOUTHERN ZONES, RESULTING IN CLOUDY SKIES THAT
PERSIST INTO MOST OF WEDNESDAY ACROSS THE DELMARVA.
LEE CYCLOGENESIS IS CURRENTLY TAKING PLACE IN THE CO FRONT RANGE
OF THE ROCKIES. THIS SURFACE LOW WILL MEANDER OVER THE CENTRAL
PLAINS FOR THE NEXT FEW DAYS AS THE UPPER TROUGH TIED TO THE
SURFACE LOW REMAINS CUTS OFF. THE CUTOFF LOW IS FORECAST TO
EVENTUALLY WEAKEN AND BECOME AN OPEN WAVE BY THURSDAY. IN RESPONSE
TO THE EVOLVING UPPER PATTERN, THE SURFACE LOW WILL PROGRESS
EASTWARD ALONG THE STATIONARY BOUNDARY TO OUR SOUTH ON THURSDAY. A
SECONDARY WAVE OF LOW PRESSURE MAY DEVELOP AND RIDE THE FRONT ON
FRIDAY. OVERRUNNING PRECIP SHOULD EXPAND NORTHWARD LATE WEDNESDAY
NIGHT INTO THURSDAY AS THE FLOW BACKS MORE OUT OF THE SOUTH AHEAD
OF THE LOW AND ISENTROPIC LIFT STRENGTHENS ALONG AND ON THE COOL
SIDE OF THE BOUNDARY. THERE IS STILL UNCERTAINTY REGARDING HOW FAR
NORTH THE FRONT AND PRECIP ADVANCES WITH DRIER AIR BEING
REINFORCED BY HIGH PRESSURE ANCHORED TO OUR NORTH. THERE IS SOME
EVIDENCE FROM GUIDANCE THAT EVAPORATIVE COOLING AT THE ONSET COULD
LEAD TO A COLD AIR DAMMING PATTERN IF THERE IS ENOUGH LOW-LEVEL
DRY AIR IN PLACE WHEN THE OVERRUNNING PRECIP MOVES IN. THIS WOULD
KEEP THE FORECAST AREA ON THE COLD SIDE OF THE BOUNDARY. WE WILL
CONTINUE TO SHOW THE HIGHEST POPS ACROSS OUR SOUTHERN AREAS DUE TO
THE PROXIMITY OF THE FRONT.
THERE COULD CONTINUE TO BE SOME SHOWERS DURING THE DAY FRIDAY AS A
SHORT WAVE PUSHES ACROSS THE AREA AND THE FRONT CONTINUES TO PUSH
FURTHER TO OUR SOUTH. SATURDAY LOOKS DRY AS HIGH PRESSURE BRIEFLY
BUILDS BACK INTO THE MID ATLANTIC. SHOWERS MAY RETURN SUNDAY INTO
MONDAY AS YET ANOTHER WAVE OF LOW PRESSURE IS EXPECTED TO ORGANIZE
OVER THE GREAT PLAINS AND TRACK EASTWARD ALONG THE STATIONARY
FRONT.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
VFR THRU AT LEAST 18Z FOR THE TERMINALS. THE WIND ARE STILL RATHER
LIGHT SO FAR MORNING FROM PHL NORTHWARD. FARTHER SOUTH IN THE WARM
SECTOR, SW WINDS ARE GUSTING 20-25 KT. EXPECT WIND GUSTS OF
SIMILAR MAGNITUDE TO DEVELOP FARTHER NORTH LATE THIS MORNING AND
EARLY AFTERNOON.
THE AFTERNOON IS EXPECTED TO BEGIN WITH VFR CONDITIONS ALONG WITH
A CONTINUATION OF THE GUSTY WEST SOUTHWEST WIND. HOWEVER, A COLD
FRONT APPROACHING FROM THE NORTH SHOULD BRING SHOWERS AND
THUNDERSTORMS. THE THUNDERSTORMS WILL BE ACCOMPANIED BY BRIEFLY
MODERATE TO HEAVY RAINFALL, LOW CEILING AND VISIBILITY VALUES, AND
PERHAPS WIND GUSTS IN EXCESS OF 35 KNOTS.
THE FRONT IS ANTICIPATED TO PASS THROUGH KABE, KRDG AND KTTN
BETWEEN ABOUT 2200 AND 2300Z BRINGING AND END TO THE POTENTIAL FOR
SHOWERS AND THUNDERSTORMS. THE FRONT IS EXPECTED TO ARRIVE AT KPNE
AND KPHL AROUND 0000Z, AND AT KILG, KACY AND KMIV ABOUT 0100Z. THE
WIND IS FORECAST TO SHIFT TO THE NORTHWEST, THEN TO THE NORTH AND
NORTHEAST AND SPEEDS SHOULD DECREASE TO AROUND 8 TO 12 KNOTS.
OUTLOOK...
WEDNESDAY...MVFR CIGS POSSIBLE FOR THE SOUTHERN TWO-THIRDS OF THE
AREA, WITH VFR POSSIBLE NORTHERN AREAS.
WEDNESDAY NIGHT...VFR EXPECTED.
THURSDAY-THURSDAY NIGHT...VFR EARLY, BECOMING MVFR OR IFR LATE IN
THE DAY AND OVERNIGHT WITH RAIN POSSIBLE.
FRIDAY-FRIDAY NIGHT...MVFR CIGS POSSIBLE WITH SCATTERED SHOWERS.
SATURDAY...VFR CIGS, WITH PERIODS OF MVFR POSSIBLE.
&&
.MARINE...
THE SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR OUR OCEAN WATERS
FOR TODAY AND TONIGHT. THE ADVISORY IS MAINLY IN EFFECT FOR WAVE
HEIGHTS AROUND 5 FEET. HOWEVER, LOCALIZED GUSTS NEAR 25 KNOTS ARE
POSSIBLE. A SMALL CRAFT ADVISORY HAS BEEN ISSUED FOR DELAWARE BAY
AND IT IS IN EFFECT UNTIL 600 PM.
THE WIND DIRECTION IS FORECAST TO FAVOR THE SOUTHWEST FOR TODAY.
A COLD FRONT FROM THE NORTH WILL DROP THROUGH THE REGION THIS
EVENING AND THE WIND DIRECTION IS EXPECTED TO SHIFT TO THE
NORTHWEST TO NORTHEAST QUADRANT.
OUTLOOK...
WEDNESDAY-SATURDAY...SUB-SMALL CRAFT ADVISORY CONDITIONS EXPECTED
TO CONTINUE. WINDS COULD PERIODICALLY GUST AROUND 20 KNOTS,
ESPECIALLY THURSDAY AND THURSDAY NIGHT WHEN GUSTS COULD APPROACH
ADVISORY LEVELS.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ430-
431.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...KLEIN
SHORT TERM...IOVINO
LONG TERM...KLEIN/ROBERTSON
AVIATION...IOVINO/KLEIN/ROBERTSON
MARINE...IOVINO/ROBERTSON
Area Forecast Discussion
National Weather Service Lincoln IL
1047 AM CDT TUE APR 26 2016
.SHORT TERM...(Today)
ISSUED AT 335 AM CDT Tue Apr 26 2016
Weak cold currently stretching from northwest Indiana southwest
through our far northern counties into northeast Missouri will slide
south across the forecast area today. Convection has had a hard time
developing along the boundary overnight due to weak convergence and
stronger lift further north with the surface low. Short term models
suggest other than some isolated showers along the southward moving
boundary, the better threat for showers and thunderstorms will be
associated with shortwave energy now pushing through central Kansas.
Convection has already started just ahead of that feature well to
our west with the stronger convection progged to shift east and
affect our southeast counties this afternoon.
Looks like a fairly sharp cutoff to the precip along and north of
Interstate 74 where the lower POPs will be today, while areas south
of I-72 will have the higher rain threat this afternoon. Surface
based capes of around 2500 J/Kg were noted south of I-72 this
afternoon, although 0-6km shear values were not much higher than 25
kts during this same time period. Hail and gusty winds will be
possible over southeast Illinois with this cluster of storms this
afternoon. With the frontal boundary shifting into southeast
Illinois later today, will have a rather large temperature gradient
this afternoon with forecast highs ranging from around 70 over our
far northern counties, to the lower 80s over extreme southeast
Illinois.
.LONG TERM...(Tonight through Monday)
ISSUED AT 335 AM CDT Tue Apr 26 2016
Forecast really is not changing much in this round, with the
exception of maybe building a bit of a break into the evening hours
without precip. However, the deep low spinning out over the Plains
and developing storm system will slowly spread rain/thunder into the
region after midnight especially...along a developing warm frontal
feature. The surface low remains out to the west for Wednesday and
is slow to progress with the deep low over eastern Canada/NE CONUS.
Much of Central Illinois remains in the warm sector with a potential
for some persistent and good rain Wed-Wed night along...up to an
inch or so. Low slow to move out Thursday as the rain comes to an
end briefly with a break before the next wave ejects out of the SW
across the Midwest for the weekend.
Rain chances return for Friday night through the weekend with a
similar setup happening again. Some variability in the
tracks/strength of the sfc system. The ECMWF is initially more well
developed with a classic low...but both the European and the GFS get
a messier look by the end of the weekend, with the system shearing
out over the Ohio River Valley and slowing any progression. Either
way, next weekend looks wetter than not.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1045 AM CDT Tue Apr 26 2016
Updated the forecast to increase chances of showers and
thunderstorms south of I-72 this afternoon and also increase cloud
cover across CWA. MCS over southern IA and northern MO is
spreading clouds eastward toward I-57 late this morning, while
leading edge of showers and thunderstorms moving into west central
IL just west of CWA. HRRR model seems 1-2 hours too slow with this
convection spreading ESE across areas south of I-74 this
afternoon and following the quicker SPC high res model solution.
SPC has slight risk of severe storms over much of Clay and sw
Jasper counties by late afternoon. Frontal boundary is pressing
southward toward I-72 late this morning and will push south of
I-70 late this afternoon. Temps currently range from mid 60s from
Macomb to Lacon north to the mid 70s from I-72 south. Highs today
to range from the upper 60s to near 70F from Galesburg and Lacon
north to the upper 70s and lower 80s from I-72 south.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Smith
LONG TERM...HJS
AVIATION...07
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
704 AM CDT TUE APR 26 2016
.UPDATE...
ISSUED AT 702 AM CDT TUE APR 26 2016
THE GROWING MISSOURI MCS HAS PRODUCED FORCING FOR SHOWERS ALL THE
WAY UP TO JUST SOUTH OF INTERSTATE 80 IN CENTRAL IOWA. THIS IS
ONLY BEING HANDLED BY THE HRRR AND PARTIALLY THE 06Z NAM. I HAVE
UPDATED THE SLIGHT CHANCE POPS IN THE SOUTH AND EXPANDED AND UPPED
THEM TO INCLUDE SOME EMBEDDED THUNDER THIS MORNING.
ERVIN
&&
.SYNOPSIS...
ISSUED AT 307 AM CDT TUE APR 26 2016
A COLD FRONT HAS NOW PUSHED INTO OUR FAR SOUTHERN COUNTIES...WITH
ANOTHER PUSH OF SIGNIFICANTLY COLDER AIR ARRIVING TOWARD SUNRISE
THIS MORNING...AS LAKE MICHIGAN AFFECTED AIR PUSHES SOUTHWEST OVER
OUR NORTHERN COUNTIES. THIS WILL CREATE A STRONG TEMPERATURE
CONTRAST OVER THE CWA TODAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CDT TUE APR 26 2016
BY 7 AM...THE NORTHEAST WINDS AND STRATUS ASSOCIATED WITH THE LAKE
MICHIGAN AFFECTED COLD WILL SPREAD INTO THE NORTHEAST
COUNTIES...POSSIBLY AS FAR SOUTH TO REACH HIGHWAY 30. BY MID
MORNING...THE STRATUS SHOULD REACH DOWN TO CEDAR RAPIDS AND THE QUAD
CITIES. HOWEVER...FARTHER SOUTH...BY MID MORNING...THE STRONG
SUNSHINE MIXED WITH MID CLOUDS AND HIGH CLOUDS SHOULD ALLOW FOR
HEATING THAT MAY HALT THE STRATUS FROM GOING MUCH FARTHER SOUTH
DURING THE DAY. THIS CREATES A DAY WHERE THE SOUTH SHOULD WARM UP TO
THE MID TO UPPER 70S...WHILE THE NORTH STRUGGLES THROUGH TO HIGHS
ONLY IN THE UPPER 50S...AND DEPENDING ON WHERE THE STRATUS CAN STAY
OPAQUE THROUGH THE DAY...THAT MAY BE OPTIMISTIC.
DESPITE THE CHALLENGING TEMPERATURES TODAY...IS SHOULD BE DRY DAY
FOR NEARLY OFF THE CWA...AS ONLY THE FAR SOUTH COULD SEE SOME LIGHT
RAIN SHOWERS FROM THE NORTHERN EDGE OF THE MISSOURI ACTIVITY...WHICH
SHOWS A MORE LIKELY CHANCE TO DROP SOUTHEAST...MISSING OUR CWA ALL
TOGETHER. THE NEXT CHANCE FOR RAIN WILL ARRIVE TONIGHT...MAINLY IN
THE SOUTHWEST COUNTIES. LOOKING SYNOPTICALLY...DESPITE THE WARM
FRONT NEAR NORTHERN MISSOURI...THERE WILL BE RIDGING ALOFT UNTIL
LATE TONIGHT. THAT SHOULD KEEP THE FOCUS FOR WAA DRIVEN SHOWERS AND
THUNDERSTORMS WEST OF EASTERN IOWA FOR QUITE A WHILE BEFORE A MORE
WIDESPREAD RAIN ARRIVES LATE TONIGHT. THE LOW LEVEL CAA WILL
CONTINUE AS STRENGTHENING NORTHEAST WINDS USHER IN LOW DEWPOINTS.
THUS...ANY RAIN WILL RAPIDLY COOL OFF TEMPERATURES EVEN FURTHER
THROUGH WETBULB AFFECTS. THIS WILL CREATE A COLD MARCH LIKE
NIGHT...WITH RAIN ARRIVING IN MOST AREAS AFTER MIDNIGHT...AND ONLY
EMBEDDED RUMBLES OF THUNDER EXPECTED AS CONVECTION ARRIVING FROM
FARTHER SOUTHWEST STRATIFIES INTO A LIGHT TO MODERATE RAIN SHIELD.
THE LATE ARRIVAL OF RAIN TONIGHT...RESULTS IN A NEARLY DRY FORECAST
FOR THE NEXT 24 HOURS IN OUR NORTHEASTERN COUNTIES EAST OF DUBUQUE.
ERVIN
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 307 AM CDT TUE APR 26 2016
FORECAST FOCUS ON TWO STRONG STORM SYSTEMS BRINGING WIDESPREAD RAIN
AND EMBEDDED THUNDERSTORMS. TEMPERATURES WILL BE BELOW NORMAL
DURING MUCH OF THE EXTENDED PERIOD.
WEDNESDAY THROUGH THURSDAY...MODELS HAVE BEEN FAIRLY CONSISTENT WITH
SHOWING LOW PRESSURE LIFTING OUT OF THE CENTRAL PLAINS AND INTO IOWA
AS A NEGATIVE-TILT TROUGH. STRONG FORCING WILL ACCOMPANY THIS SYSTEM
WITH A NICE WARM MOIST CONVEYOR BELT FROM THE SOUTH LIFTING OVER THE
COOL AIRMASS IN THE CWA...DUE TO A NORTHEAST TO EAST WIND COMING OFF
THE GREAT LAKES. A FRONTAL BOUNDARY WILL BE NEARLY STALLED IN FAR
NORTHERN MO. WIDESPREAD MODERATE RAIN AND EMBEDDED THUNDERSTORMS
WILL BE THE RULE WITH QPF AMOUNTS AT LEAST IN THE 1/2 TO 1 INCH
RANGE...POSSIBLY SOME HIGHER AMOUNTS WITH PWAT`S OVER 1.30 INCHES.
THERE IS THE POTENTIAL FOR A FEW STRONGER STORMS IN OUR FAR SOUTHERN
CWA CLOSER TO THE BOUNDARY AND SURFACE LOW. HOWEVER...THE MAIN
SEVERE WEATHER EVENT SHOULD REMAIN FARTHER SOUTH IN MO AND INTO THE
LOWER MS VALLEY. THE SYSTEM WILL BE OCCLUDING LATER WEDNESDAY NIGHT
CUTTING OFF THE DEEPER MOISTURE SOURCE WITH THE RAIN BECOMING
SCATTERED AND LIGHT. THE OCCLUDED LOW AND ASSOCIATED COLD POOL WILL
DRIFT ACROSS THE DVN CWA ON THURSDAY SO WILL KEEP THE MENTION OF
SCATTERED RAIN SHOWERS. TEMPERATURES ON WEDNESDAY WILL RANGE FROM
THE LOWER TO MID 50S NORTH TO THE MID TO UPPER 60S SOUTH. THIS WILL
FEEL LIKE A RAW DAY IN OUR NORTHERN COUNTIES WITH RAIN...COOL
TEMPERATURES AND AN EAST WIND GUSTING TO 30 MPH. HIGHS ON THURSDAY
WILL RANGE FROM THE LOWER 50S NORTH TO THE MID 60S FAR SOUTH.
THURSDAY NIGHT THROUGH FRIDAY...TIME TO BRIEFLY DRY OUT AS WEAK HIGH
PRESSURE RIDGE BUILDS INTO THE AREA FROM THE NORTH. HIGHS ON FRIDAY
WILL BE A TAD WARMER AS ANOTHER STRONG STORM SYSTEM BEGINS TO TAKE
SHAPE IN THE CENTRAL PLAINS.
FRIDAY NIGHT THROUGH SUNDAY...ANOTHER STRONG STORM SYSTEM WILL TRACK
OUT OF THE CENTRAL PLAINS AND THEN SLOWLY INTO THE CORN BELT. THIS
LOOKS TO BE A SIMILAR SET UP AS THE MID WEEK EVENT IF NOT A BIT
FARTHER NORTH. SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS CAN BE
EXPECTED DURING THE WEEKEND WITH WIDESPREAD QPF AMOUNTS ONCE AGAIN
AT LEAST 1/2 TO 1 INCH. IF THE ECWMF IS CORRECT THERE IS THE
POTENTIAL FOR STRONG STORMS ON SUNDAY ESPECIALLY IN WESTERN IL AS
THE SURFACE LOW TRACKS NEAR THAT AREA. HOWEVER...THE GFS TAKES THE
LOW FARTHER TO THE SOUTH WHICH WOULD REDUCE THIS POTENTIAL.
TEMPERATURES OVER THE WEEKEND WILL ONCE AGAIN BE BELOW NORMAL WITH
HIGHS IN THE 50S NORTH TO 60S SOUTH.
HAASE
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 610 AM CDT TUE APR 26 2016
A CHALLENGING AVIATION DAY AND NIGHT ARE IN STORE THROUGH
WEDNESDAY MORNING...AS LOW STRATUS AROUND 800 TO 1500 FT SPREAD
SOUTHWEST OUT OF WISCONSIN THIS MORNING...LIKELY REACHING BOTH CID
AND MLI BEFORE STALLING OUT NORTH OF BRL. A WARM FRONT WILL
DEVELOP OVER NORTHERN MISSOURI TODAY...TURNING ALL WINDS IN
EASTERN IOWA AND NORTHWEST ILLINOIS TO THE NORTHEAST AT 15 TO 25
KTS. AFTER SOME IMPROVEMENT TO VFR DURING THE AFTERNOON AND
EVENING HOURS...ANOTHER LAKE ENHANCED STRATUS DECK SHOULD MOVE
OVER THE ENTIRE AREA TONIGHT...LASTING THROUGH WEDNESDAY. RAIN
WILL ALSO SPREAD IN FROM MISSOURI LATE TONIGHT.
ERVIN
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...ERVIN
SYNOPSIS...ERVIN
SHORT TERM...ERVIN
LONG TERM...HAASE
AVIATION...ERVIN
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
726 AM EDT TUE APR 26 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 401 AM EDT TUE APR 26 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW SHRTWV MOVING THRU
THE UPR GREAT LKS EARLY THIS MRNG. BUT SINCE THIS DISTURBANCE IS
ENTERING CONFLUENT ZN BTWN NW FLOW OVER ONTARIO ARND CLOSED UPR LO
OVER THE CNDN MARITIMES AND WLY SRN BRANCH FLOW OVER THE CONUS...
THIS DISTURBANCE IS WEAKENING AS HINTED BY WARMING CLD TOP TEMPS
OVER THE CWA. MOST OF THE LINGERING PCPN IN THE FORM OF RA/SN IS OVER
THE E HALF CLOSER TO THE EXITING/WEAKENING DISTURBANCE...BUT
LINGERING LLVL MSTR UNDER THE MID LVL DRYING/SUBSIDENCE IN ITS WAKE
IS ALLOWING SOME LIGHT DRIZZLE/FLURRIES TO LINGER FARTHER W...
ESPECIALLY WHERE LLVL GUSTY NE FLOW IS UPSLOPING. BUT MUCH DRIER LLVL
AIR IS JUST TO THE N ASSOCIATED WITH HI PRES BLDG INTO NRN ONTARIO.
THE 00Z YPL RAOB IS QUITE DRY IN THE LLVLS...WITH H925/H85 DEWPT
DEPRESSIONS 17C/11C. STLT IMAGERY SHOWS THE NRN EDGE OF THE CLDS ARE
MOVING STEADILY TO THE S ACRS LK SUP WITH THIS DRY ADVECTION IN THE
LLVL NE FLOW. THIS CLRG LINE IS APRCHG THE KEWEENAW AT FCST ISSUANCE.
LOOKING TO THE W...THERE IS ANOTHER WEAKER SRN BRANCH SHRTWV SLIDING
E THRU CENTRAL MN.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON LLVL DRYING TRENDS/
IMPACT ON LINGERING LGT PCPN THIS MRNG AND THEN MIN TEMPS TNGT AS
DRIER/CHILLY AIRMASS ASSOCIATED WITH ONTARIO HI PRES WL DOMINATE.
TODAY...ALTHOUGH THERE ARE SOME DIFFERENCES ON THE TIMING...SHORTER
TERM MODELS ALL SHOW STEADY LLVL DRYING TODAY IN CONTINUED STEADY/
SLOWLY WEAKENING NE FLOW ON THE SRN FLANK OF ONTARIO HI PRES. GIVEN
THE STLT CLD TRENDS/FALLING SFC DEWPTS JUST TO THE N...PREFER THE
MODELS THAT SHOW MORE AGGRESSIVE LLVL DRYING. SO EXPECT LINGERING
DRIZZLE/FREEZING DRIZZLE/FLURRIES TO DIMINISH AND END BY ABOUT
12Z...LAST IN THE UPSLOPE HIER TERRAIN AREAS OF THE NCNTRL. SOME LO
CLDS MAY LINGER A BIT LONGER...BUT EVEN THESE SHOULD DISSOLVE N-S BY
LATE MRNG. ALTHOUGH SHRTWV IN MN IS FCST TO SLIDE E AND BRING SOME
DPVA/DEEP LYR QVECTOR CNVGC MAINLY TO THE WI BORDER AREAS...INFLUX OF
LLVL DRY AIR WL PREVENT ANY PCPN AND LIMIT IMPACT TO JUST MORE MID/HI
CLDS. DESPITE THE RETURN OF SOME SUNSHINE ESPECIALLY OVER THE NRN
TIER...NE FLOW OFF THE CHILLY LK SUP WATERS WL LIMIT DIURNAL TEMP
RECOVERY TO NO HIER THAN ABOUT 40 NEAR THE LK. TEMPS WL TOP OUT ARND
50 OVER THE SCENTRAL.
TNGT...ANY LINGERING CLDS ASSOCIATED WITH THE SECOND SHRTWV WL CLR
THE FAR SCENTRAL BY 00Z THIS EVNG...SETTING THE STAGE FOR A CHILLY
NGT AS THE SFC HI PRES IN ONTARIO EXTENDS A SFC RDG AXIS INTO THE
UPR LKS UNDER LARGE SCALE SUBSIDENCE. THE ONLY LIMITING FACTOR WL BE
A PERSISTENT LIGHT NE FLOW TO THE S OF THE HI CENTER LINGERING OVER
ONTARIO. BUT WITH PWAT FALLING AOB 0.25 INCH...WL TEND TOWARD THE LO
END OF GUIDANCE FOR THE INTERIOR SHELTERED LOCATIONS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 409 AM EDT TUE APR 26 2016
SPLIT FLOW ACROSS NORTH AMERICA. SHARP TROUGH IN THE NORTHERN POLAR
JET STREAM PERSISTS OVER EASTERN CANADA MOST OF THE WEEK. STRONG
TROUGH IN THE SOUTHERN STREAM PUSHING ACROSS THE WESTERN CONUS ATTM
SHEARS OUT WED INTO THU AS IT PUSHES INTO CONFLUENT FLOW ON WESTERN
EDGE OF THE EASTERN CANADA UPPER TROUGH. ANOTHER TROUGH MOVES ACROSS
WESTERN CONUS FRIDAY AND AS THAT SYSTEM LIFTS TOWARD GREAT LAKES LATE
IN THE WEEKEND COULD SEE SOME LIGHT PRECIPITATION. APPEARS COOLER
AND UNSETTLED WEATHER MAY LINGER EARLY NEXT WEEK AS THIS UPPER LOW
MEANDERS OVER THE GREAT LAKES. LATEST CPC FORECAST THEN SHOWS
GREATER CHANCES FOR ABOVE NORMAL TEMPS AND BELOW NORMAL PRECIP SETS
UP FOR MAY 3RD THROUGH MAY 8TH.
AS IT HAS LOOKED LIKE FOR A WHILE...MAIN SFC FEATURE THIS WEEK WILL
BE HIGH PRESSURE VCNTY OF HUDSON BAY WITH RIDGING EXTENDING OVER THE
UPPER GREAT LAKES. AS THE SHORTWAVE TROUGH CURRENTLY MOVING ACROSS
THE ROCKIES TO THE PLAINS TODAY LIFTS TOWARD UPPER GREAT LAKES WED
NIGHT INTO THU...SHOULD SEE INCREASING MID CLOUDS...ESPECIALLY OVER
SOUTH HALF OF CWA. WEAKENING FORCING ALONG WITH SOUNDINGS SHOWING
DRY AIR WITH THE HIGH BLO 700MB INDICATES MINIMAL CHANCES OF RAIN
OVER SOUTH CENTRAL ON THU. WEAKENING SYSTEM DEPARTS THU NIGHT THEN
COULD SEE INCREASING MID CLOUDS AGAIN FRI AS ANOTHER SYSTEM SHEARS
OUT WHILE MOVING FM THE CENTRAL PLAINS TOWARD THE STRONG LOW-LEVEL
RIDGE. GRADUALLY WARMING H85 TEMPS SHOULD ALLOW TEMPS INLAND TO
SLOWLY WARM THROUGH THE 50S TO POSSIBLY LOWER 60S BY FRI OR SAT.
GRADIENT NORTHEAST WINDS OUT OF THE HIGH WILL KEEP LK SUPERIOR SHORE
MAINLY IN THE 40S. WITH THE HIGH AND DRY AIRMASS IN VCNTY CONTINUE
TO PREFER NIGHTTIME TEMPS AT OR BLO FREEZING INLAND FOR THE REST OF
THE WEEK. DRY AIR SHOULD ALSO LEAD TO LOW TD/RH IN THE AFTN. WINDS
FOR MOST PART LOOK LIGHT SO EVEN THOUGH FIRE WEATHER CONCERNS WILL
BE INCREASING...THEY SHOULD BE KEPT IN CHECK.
CONSENSUS CONTINUES TO SHOW SLIGHT CHANCE POPS LATER IN THE WEEKEND
AS YET ANOTHER UPPER TROUGH MOVES TOWARD GREAT LAKES. PREVIOUS ECMWF
WAS SHOWING SYSTEM BEGINNING TO AFFECT AREA AS EARLY AS SAT NIGHT
BUT 00Z RUN DELAYS THE WEAKENING SYSTEM UNTIL LATE SUN INTO SUN
NIGHT/MON. GFS AND GEM-NH ARE SHUNTED MORE TO THE SOUTH...WHICH
MAKES SENSE GIVEN THE STRONG DRY HIGH PRESSURE PERSISTING. OVERALL
NOT LOOKING LIKE MUCH OF A CHANCE FOR RAIN FOR THE EXTENDED PERIOD
UNTIL EARLY NEXT WEEK...MAYBE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 725 AM EDT TUE APR 26 2016
AS LLVL DRY AIR IN THE NE FLOW TO THE S OF BLDG HI PRES IN ONTARIO
PUSHES INTO UPR MI...WHICH HAS ALREADY ARRIVED AND CLEARED THE LO
CLDS AT CMX...EXPECT LINGERING LO CLDS AT SAW AND IWD TO CLEAR THIS
MRNG. VFR CONDITIONS WL THEN PREVAIL THIS FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 401 AM EDT TUE APR 26 2016
ENE WINDS UP TO 25-30 KTS OVER THE LAKE THIS MORNING...STRONGEST
OVER THE W...WILL DIMINISH THROUGH THE DAY TO UNDER 20 KTS AS A HI
PRES RIDGE BUILDS S THRU ONTARIO AND THE PRES GRADIENT WEAKENS. E TO
NE WINDS GENERALLY UNDER 20-25KT WILL THEN PREVAIL THRU SAT TO THE S
OF PERSISTENT HI PRES NEAR HUDSON BAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
721 AM CDT TUE APR 26 2016
.UPDATE...
ISSUED AT 719 AM CDT TUE APR 26 2016
THE RAP MODEL IS TRENDING COLDER. THE COLD AIR IS OVER-TAKING THE
FCST AREA AND SNOW IS UNDERWAY ACROSS NORTHWEST NEB IN SOUIX
COUNTY. SNOW MAY BE UNDERWAY IN PARTS OF SHERIDAN COUNTY ALSO. A
NEW FORECAST IS OUT FOR PERIODS OF SNOW AND COOLER TEMPERATURES
TODAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CDT TUE APR 26 2016
TODAY AND TONIGHT...THE SFC FRONT NEAR DODGE CITY AT 06Z LIFTS NORTH
TO NEAR THE KANSAS NEBRASKA BORDER BY 12Z AND REMAINS STATIONARY
TODAY. THE FRONT THEN GETS SWEPT EAST AND SOUTH TONIGHT AS SFC LOW
PRESSURE DEEPENS ACROSS NCNTL KS.
THE RAP MODEL SHOWS 2000 J/KG OF ELEVATED INSTABILITY JUST NORTH OF
THE SFC FRONT AT 12Z WHICH LIFTS NORTH THROUGH THE FCST AREA TODAY.
THIS INSTABILITY SHOULD BE THE CATALYST FOR THUNDERSTORMS CONTAINING
LARGE AND SMALL HAIL. THIS STORM ACTIVITY COULD BE UNDERWAY BY 12Z
ACROSS SWRN NEB. A SECOND AREA OF ELEVATED INSTABILITY SHOULD REFORM
ACROSS SWRN NEB AROUND 21Z WHICH WILL BE THE GENESIS FOR A SECOND
ROUND OF THUNDERSTORMS TONIGHT WHICH SHOULD LAST FOR MANY HOURS
ACROSS THE SANDHILLS AND PRODUCE AN AREAL AVERAGE RAINFALL NEAR 1
INCH. THE THREAT OF HAIL...LARGE AND SMALL...SHOULD CONTINUE
THROUGHOUT THE EVENING.
THE LATEST RAP MODEL PRODUCES HIGHS ONLY IN THE 40S AND 5OS TODAY.
THIS SEVERAL DEGREES COOLER THAN THE DETERMINISTIC MODEL CONSENSUS.
LOWS TONIGHT FALL INTO THE 30S AND 40S. THE NAM SUGGESTS A MIX OF
RAIN AND SNOW ACROSS SHERIDAN COUNTY WHILE THE GFS KEEPS THE PTYPE
ALL RAIN. THE GFS WAS PREFERRED AS THE SNOW AND COLDER AIR APPEARS
ELUSIVE THIS MORNING...CONFINED TO WY...ND AND MT.
THE TORNADO POTENTIAL APPEARS VERY CONDITIONAL THIS AFTERNOON AS THE
MODEL CONSENSUS LIFTS THE SFC LOW AND TRIPLE PT THROUGH KS TODAY AND
TO NEAR LINCOLN NEB BY WEDNESDAY MORNING. THIS WOULD PROBABLY KEEP
ERN LINCOLN COUNTY...FRONTIER AND SRN CUSTER COUNTIES IN THE COOL
SECTOR LESSENING THE RISK OF TORNADO DEVELOPMENT. IF THE WARM FRONT
CAN LIFT INTO SRN NEB...TO NEAR I-80 EAST OF NORTH PLATTE...THEN THE
TORNADO RISK WOULD INCREASE SIGNIFICANTLY.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 325 AM CDT TUE APR 26 2016
BEGINNING 12Z WEDNESDAY. THE NEGATIVELY TILTED UPPER LEVEL LOW IS
PROJECTED TO BE CENTERED NEAR THE KS/NEB BORDER ON WEDNESDAY. THE
PLACEMENT OF THE LOW FAVORS THE HIGHEST POPS ACROSS OUR NORTHERN
ZONES...BUT ALL AREAS HAVE A SHOT AT ADDITIONAL ROUNDS OF
SHOWERS/STORMS. THE LATEST GUIDANCE HAS BACKED OFF ON THE
INSTABILITY PARAMETERS THIS EVENING FOR WEDNESDAY...BUT SUFFICIENT
ELEVATED CAPE REMAINS FOR AT LEAST AN ISO MENTION OF THUNDER FROM
SOUTHWEST NEB NORTHEAST TO OUR NORTH CENTRAL NEB ZONES. AS THE LOW
EJECTS EAST IN THE EVENING HOURS...THE MODELS SUGGEST ENOUGH COLD AIR
ON THE BACKSIDE OF THE LOW FOR A COMPLETE CHANGE OVER TO SNOW ACROSS
NW NEB...AND A MIX AS FAR EAST AS THE HIGHWAY 83 CORRIDOR. THE
RECENT TREND OF THE MODELS HAS BEEN COOLER...WHICH WILL NEED TO BE
MONITORED IN THE EVENT THAT ACCUMULATIONS OCCUR. WARM GROUND
TEMPERATURES WILL CREATE AN UNFAVORABLE ENVIRONMENT FOR
ACCUMULATIONS ACROSS NW NEB...SO FOR NOW...WILL KEEP ACCUMULATIONS
MINIMAL. THE LOW WILL LIFT TOWARD SOUTHERN WISCONSIN ON THURSDAY
ALLOWING A LOW AMPLITUDE RIDGE TO FOLLOW. THE RIDGE WILL BE
CHARACTERIZED AS TRANSIENT AS THE NEXT LOW CLOSES ON THE PLAINS FOR
FRIDAY. TEMPERATURES WITH THE RIDGE WILL HAVE LITTLE TIME TO
RECOVER...SO THE BELOW AVERAGE HIGHS WILL CONTINUE INTO THE NEXT
SYSTEM WITH THE POSSIBILITY OF A MIX OF SNOW ONCE AGAIN ACROSS
NORTHWEST NEBRASKA EARLY FRIDAY MORNING...ELSEWHERE SHOWERS OF RAIN
ARE FORECAST. ONE WOULD EXPECT THE TRACK OF THE H5 LOW WOULD ALLOW
SOME INSTABILITY TO WORK BACK INTO SOUTHERN PORTIONS OF THE CWA AT A
MINIMUM. WILL ONCE AGAIN KEEP AN ISO T MENTION GOING IN THE
FORECAST FRIDAY AFTERNOON INTO EARLY SATURDAY. IT SHOULD BE NOTED
THAT THE ECMWF IS COOLER THAN THE GFS WITH THE WEEKEND SYSTEM...THUS
A MIX OF SNOW IS POSSIBLE ONCE AGAIN ACROSS NW NEBRASKA DURING THE
EARLY MORNING HOURS AS THE ECMWF SUGGESTS H85 T/S FALLING BELOW 0C.
ANOTHER POTENTIALLY SIGNIFICANT TREND IS THAT BOTH THE GFS AND EC
ARE GENERATING MODERATE QPF AT TIMES OVER MUCH OF THE CWA AS THE
TRACK NOW FAVORS THE SANDHILLS. IN ADDITION...AS THE H5 LOW TAKES
ON A NEGATIVE TILT OVER THE HIGH PLAINS...IT STALLS AND IMPACTS THE
CWA FOR A PERIOD OF 48 HOURS OR MORE. SOLID RAIN CHANCES WILL
CONTINUE INTO MONDAY OF NEXT WEEK WITH THE POSSIBILITY OF A MIX OF
RAIN AND SNOW ACROSS THE NORTHWEST DURING THE EARLY MORNING HOURS.
TEMPERATURES WILL BE COOL THROUGH MUCH OF THE EXTENDED GIVEN THE
PRESENCE OF CLOUDS...PRECIP AND PERIODS OF CAA. BY EARLY NEXT WEEK A
WELL DEFINED RIDGE IS SHOWN TO DEVELOP AND SPREAD WARMING TEMPS BACK
ACROSS THE CWA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 623 AM CDT TUE APR 26 2016
MIXED FLIGHT CONDITIONS MVFR/IFR ARE EXPECTED TO CONTINUE TODAY
AND TONIGHT WITH TSTMS/STRONG/SVR TSTMS. HAIL IS THE SEVERE
WEATHER CONCERN. ONCE LOW LEVEL WINDS BECOME NORTHWEST LATE
TONIGHT...CIGS SHOULD LIFT TO MVFR/VFR IN RAIN.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CDC
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
623 AM CDT TUE APR 26 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CDT TUE APR 26 2016
TODAY AND TONIGHT...THE SFC FRONT NEAR DODGE CITY AT 06Z LIFTS NORTH
TO NEAR THE KANSAS NEBRASKA BORDER BY 12Z AND REMAINS STATIONARY
TODAY. THE FRONT THEN GETS SWEPT EAST AND SOUTH TONIGHT AS SFC LOW
PRESSURE DEEPENS ACROSS NCNTL KS.
THE RAP MODEL SHOWS 2000 J/KG OF ELEVATED INSTABILITY JUST NORTH OF
THE SFC FRONT AT 12Z WHICH LIFTS NORTH THROUGH THE FCST AREA TODAY.
THIS INSTABILITY SHOULD BE THE CATALYST FOR THUNDERSTORMS CONTAINING
LARGE AND SMALL HAIL. THIS STORM ACTIVITY COULD BE UNDERWAY BY 12Z
ACROSS SWRN NEB. A SECOND AREA OF ELEVATED INSTABILITY SHOULD REFORM
ACROSS SWRN NEB AROUND 21Z WHICH WILL BE THE GENESIS FOR A SECOND
ROUND OF THUNDERSTORMS TONIGHT WHICH SHOULD LAST FOR MANY HOURS
ACROSS THE SANDHILLS AND PRODUCE AN AREAL AVERAGE RAINFALL NEAR 1
INCH. THE THREAT OF HAIL...LARGE AND SMALL...SHOULD CONTINUE
THROUGHOUT THE EVENING.
THE LATEST RAP MODEL PRODUCES HIGHS ONLY IN THE 40S AND 5OS TODAY.
THIS SEVERAL DEGREES COOLER THAN THE DETERMINISTIC MODEL CONSENSUS.
LOWS TONIGHT FALL INTO THE 30S AND 40S. THE NAM SUGGESTS A MIX OF
RAIN AND SNOW ACROSS SHERIDAN COUNTY WHILE THE GFS KEEPS THE PTYPE
ALL RAIN. THE GFS WAS PREFERRED AS THE SNOW AND COLDER AIR APPEARS
ELUSIVE THIS MORNING...CONFINED TO WY...ND AND MT.
THE TORNADO POTENTIAL APPEARS VERY CONDITIONAL THIS AFTERNOON AS THE
MODEL CONSENSUS LIFTS THE SFC LOW AND TRIPLE PT THROUGH KS TODAY AND
TO NEAR LINCOLN NEB BY WEDNESDAY MORNING. THIS WOULD PROBABLY KEEP
ERN LINCOLN COUNTY...FRONTIER AND SRN CUSTER COUNTIES IN THE COOL
SECTOR LESSENING THE RISK OF TORNADO DEVELOPMENT. IF THE WARM FRONT
CAN LIFT INTO SRN NEB...TO NEAR I-80 EAST OF NORTH PLATTE...THEN THE
TORNADO RISK WOULD INCREASE SIGNIFICANTLY.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 325 AM CDT TUE APR 26 2016
BEGINNING 12Z WEDNESDAY. THE NEGATIVELY TILTED UPPER LEVEL LOW IS
PROJECTED TO BE CENTERED NEAR THE KS/NEB BORDER ON WEDNESDAY. THE
PLACEMENT OF THE LOW FAVORS THE HIGHEST POPS ACROSS OUR NORTHERN
ZONES...BUT ALL AREAS HAVE A SHOT AT ADDITIONAL ROUNDS OF
SHOWERS/STORMS. THE LATEST GUIDANCE HAS BACKED OFF ON THE
INSTABILITY PARAMETERS THIS EVENING FOR WEDNESDAY...BUT SUFFICIENT
ELEVATED CAPE REMAINS FOR AT LEAST AN ISO MENTION OF THUNDER FROM
SOUTHWEST NEB NORTHEAST TO OUR NORTH CENTRAL NEB ZONES. AS THE LOW
EJECTS EAST IN THE EVENING HOURS...THE MODELS SUGGEST ENOUGH COLD AIR
ON THE BACKSIDE OF THE LOW FOR A COMPLETE CHANGE OVER TO SNOW ACROSS
NW NEB...AND A MIX AS FAR EAST AS THE HIGHWAY 83 CORRIDOR. THE
RECENT TREND OF THE MODELS HAS BEEN COOLER...WHICH WILL NEED TO BE
MONITORED IN THE EVENT THAT ACCUMULATIONS OCCUR. WARM GROUND
TEMPERATURES WILL CREATE AN UNFAVORABLE ENVIRONMENT FOR
ACCUMULATIONS ACROSS NW NEB...SO FOR NOW...WILL KEEP ACCUMULATIONS
MINIMAL. THE LOW WILL LIFT TOWARD SOUTHERN WISCONSIN ON THURSDAY
ALLOWING A LOW AMPLITUDE RIDGE TO FOLLOW. THE RIDGE WILL BE
CHARACTERIZED AS TRANSIENT AS THE NEXT LOW CLOSES ON THE PLAINS FOR
FRIDAY. TEMPERATURES WITH THE RIDGE WILL HAVE LITTLE TIME TO
RECOVER...SO THE BELOW AVERAGE HIGHS WILL CONTINUE INTO THE NEXT
SYSTEM WITH THE POSSIBILITY OF A MIX OF SNOW ONCE AGAIN ACROSS
NORTHWEST NEBRASKA EARLY FRIDAY MORNING...ELSEWHERE SHOWERS OF RAIN
ARE FORECAST. ONE WOULD EXPECT THE TRACK OF THE H5 LOW WOULD ALLOW
SOME INSTABILITY TO WORK BACK INTO SOUTHERN PORTIONS OF THE CWA AT A
MINIMUM. WILL ONCE AGAIN KEEP AN ISO T MENTION GOING IN THE
FORECAST FRIDAY AFTERNOON INTO EARLY SATURDAY. IT SHOULD BE NOTED
THAT THE ECMWF IS COOLER THAN THE GFS WITH THE WEEKEND SYSTEM...THUS
A MIX OF SNOW IS POSSIBLE ONCE AGAIN ACROSS NW NEBRASKA DURING THE
EARLY MORNING HOURS AS THE ECMWF SUGGESTS H85 T/S FALLING BELOW 0C.
ANOTHER POTENTIALLY SIGNIFICANT TREND IS THAT BOTH THE GFS AND EC
ARE GENERATING MODERATE QPF AT TIMES OVER MUCH OF THE CWA AS THE
TRACK NOW FAVORS THE SANDHILLS. IN ADDITION...AS THE H5 LOW TAKES
ON A NEGATIVE TILT OVER THE HIGH PLAINS...IT STALLS AND IMPACTS THE
CWA FOR A PERIOD OF 48 HOURS OR MORE. SOLID RAIN CHANCES WILL
CONTINUE INTO MONDAY OF NEXT WEEK WITH THE POSSIBILITY OF A MIX OF
RAIN AND SNOW ACROSS THE NORTHWEST DURING THE EARLY MORNING HOURS.
TEMPERATURES WILL BE COOL THROUGH MUCH OF THE EXTENDED GIVEN THE
PRESENCE OF CLOUDS...PRECIP AND PERIODS OF CAA. BY EARLY NEXT WEEK A
WELL DEFINED RIDGE IS SHOWN TO DEVELOP AND SPREAD WARMING TEMPS BACK
ACROSS THE CWA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 623 AM CDT TUE APR 26 2016
MIXED FLIGHT CONDITIONS MVFR/IFR ARE EXPECTED TO CONTINUE TODAY
AND TONIGHT WITH TSTMS/STRONG/SVR TSTMS. HAIL IS THE SEVERE
WEATHER CONCERN. ONCE LOW LEVEL WINDS BECOME NORTHWEST LATE
TONIGHT...CIGS SHOULD LIFT TO MVFR/VFR IN RAIN.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS HASTINGS NE
621 AM CDT TUE APR 26 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 321 AM CDT TUE APR 26 2016
SATELLITE AND OBSERVATIONS SHOW SOME STRATUS SPREADING ACROSS THE
FORECAST AREA THIS MORNING. RADAR HAS A SINGLE CELL IN NORTH CENTRAL
KANSAS AND MAYBE A FEW SPRINKLES ACROSS SOUTHWEST NEBRASKA.
STILL A LOT OF DIFFERENCES IN THE MODELS THIS MORNING CONSIDERING
THAT THE MAIN EVENT IS LESS THAN 24 HOURS OUT. NEARLY ALL OF THE
MODELS HAVE THERE BEING PRECIPITATION ACROSS THE ENTIRE FORECAST
AREA THROUGH MUCH OF THE PERIOD. THE DETAILS ARE THE PART THAT
CREATE THE CHALLENGE. THE UPPER LOW IS TO THE WEST OF THE FORECAST
AREA AND THE FIRST WAVE OF ENERGY FROM THE LOW IS MOVING INTO THE
AREA EARLY THIS MORNING. THE SURFACE LOW IS STILL TO THE
WEST/SOUTHWEST OF THE FORECAST AREA THIS MORNING AND THERE IS A WARM
FRONT THAT EXTENDS TO THE EAST OF THE FRONT ACROSS NORTHERN KANSAS.
THE CURRENT CONVECTION IS TO THE NORTH OF THE FRONT IN AN AREA OF
WARM MOIST ADVECTION. THE INCREASE OF LOW LEVEL MOISTURE HAS THE
POTENTIAL TO BRING SOME FOG AND MAYBE SOME DRIZZLE TO THE AREA. THE
MAIN AREA WOULD BE TO THE NORTH OF THE FRONT. FOR NOW HAVE SOME
AREAS OF DRIZZLE AND PATCHY FOG.
WITH THE START OF THE CONVECTION ALREADY IN NORTH CENTRAL KANSAS
THERE IS ALREADY SIGNIFICANT CAPE AND SHEAR AND THUNDERSTORMS THIS
MORNING WOULD LIKELY BE SEVERE. THIS ACTIVITY SHOULD BE DECREASING
AROUND SUNRISE AS IT MOVES TO THE EAST.
ONE OF THE MAIN VARIABLES FOR TODAY AND TONIGHT IS THE LOCATION OF
THE SURFACE LOW AND WARM FRONT. SOME OF THE MODELS PUSH THE WARM
FRONT TO THE NORTH...WHILE OTHERS KEEP IT FURTHER TO THE SOUTH. HAVE
KEPT WITH THE FURTHER SOUTH THEORY SINCE THERE COULD BE STRATUS
AROUND THIS MORNING AND INTO THE EARLY AFTERNOON THAT WOULD SLOW THE
FRONT MOVING TO THE NORTH. MOST OF THE MODELS ALSO KEEP THE SURFACE
LOW NEAR THE KANSAS/NEBRASKA BORDER THROUGH THE DAY.
THE NEXT QUESTION WILL BE HOW MUCH PRECIPITATION WILL THERE BE MID
MORNING TO MID AFTERNOON. THE NAM...GFS...ECMWF AND A FEW OF THE
SHORT TERM MODELS HAVE CONVECTION SPREADING ACROSS THE FORECAST AREA
DURING THE MORNING HOURS. ON THE OTHER HAND THE HRRR AND SOME OF THE
OTHER SHORT TERM MODELS HAVE A DRY OR NEARLY DRY PERIOD FOR MID DAY.
HAVE KEPT THE POPS DURING THE DAY...BUT HAVE A FEW CONCERNS HOW MUCH
THERE WILL BE.
WHEN WILL CONVECTION GET GOING THIS AFTERNOON? MOST OF THE MODELS
HAVE CONVECTION STARTING SOMETIME AROUND 21 TO 00Z THIS AFTERNOON
AND CONTINUING THROUGH THE NIGHT. THE BEST CHANCES WILL BE DURING
THE EVENING HOURS. ANOTHER CONCERN IS THAT SOME OF THE MODELS ARE
BRINGING IN A DRY SLOT INTO THE SOUTHERN PORTION OF THE FORECAST
AREA. WILL HAVE TO WATCH THIS TO SEE JUST WHERE AND HOW FAR IT MOVES
INTO THE AREA LATE TONIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 321 AM CDT TUE APR 26 2016
IT IS NO QUESTION THAT THE MAIN CONCERNS LIE WITHIN THE SHORT-
TERM...BUT THE MID AND EXTENDED ARE STILL ACTIVE AND INTERESTING
IN THEIR OWN RIGHT.
MID-TERM (WEDNESDAY - THURSDAY):
THE MAIN FOCUS IN THIS PERIOD IS THE EXIT OF THE UPPER LEVEL LOW
THAT BEGINS TO IMPACT US TODAY. ONCE THE UPPER DISTURBANCE ROTATES
FROM THE SOUTHWEST INTO NEBRASKA EARLY WEDNESDAY MORNING IT
BECOMES RELATIVELY STAGNANT AND SLOW MOVING. THIS CAUSED THE
MULTIPLE PV ANOMALIES ROTATING AROUND THE UPPER LOW TO CAUSE
CHANCES FOR RAIN THROUGHOUT WEDNESDAY. THINK THE BEST CHANCES WILL
BE OVER SOUTH CENTRAL NEBRASKA ALONG AND NORTH OF WHERE THE
SURFACE LOW TRACKS. THERE ARE SOME DISCREPANCIES ON HOW THE
QUICKLY THE UPPER LOW EJECTS EASTWARD WITH THE GFS AND EC MORE
PROGRESSIVE WHILE THE NAM ROTATES THE ENERGY BACK NORTHWARD OVER
THE NORTHERN PLAINS. REGARDLESS THINK PRECIPITATION WILL WANE LATE
WEDNESDAY AND THAT THE ARE WILL BE MOSTLY DRY WEDNESDAY OVERNIGHT
INTO THURSDAY MORNING.
THURSDAY IS EXPECTED TO BE DRY...BUT THE ACTIVE PATTERN CONTINUES
AS THE NEXT DISTURBANCE APPROACHES FROM THE WEST THURSDAY NIGHT.
IN THE WARM SECTOR AHEAD OF THE NEXT WAVE PRECIPITATION IS
EXPECTED TO DEVELOP FROM SOUTHWEST MOVING TO THE NORTHEAST.
LONG-TERM (FRIDAY - MONDAY):
THIS PERIOD IS LIKELY TO BE WET AT LEAST OFF AND ON. THE UPPER LOW
WILL PROGRESS EASTWARD SLOWLY WHILE THE SURFACE LOW TRACKS
NORTHEAST ACROSS THE AREA AS WELL. PRECIPITATION POTENTIAL IS
FAIRLY HIGH. WATER COULD BE COME A CONCERN. WATCH THIS PERIOD AS
IT NEARS.
THE MAJORITY OF THE FORECAST WAS FOCUSED ON THE SHORT AND MID-TERM
WITH ONGOING CONVECTION...THE LONG-TERM FORECAST IS ABBREVIATED
BECAUSE OF THIS.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 616 AM CDT TUE APR 26 2016
THE MAIN CONVECTION THIS MORNING WILL HAVE LITTLE IMPACT FOR THE
TERMINALS. THE LOWER CLOUDS HAVE BEEN MOVING TO THE NORTH AND IF
THEY ARE NOT IN THE TERMINAL AREAS BY START OF THE TAF...IT SHOULD
BE SOON. STILL SOME TIMING CONCERNS WITH THE THUNDERSTORMS. THE
BEST CHANCE FOR THUNDERSTORMS WILL BE THIS AFTERNOON AND
EVENING...BUT THERE IS A CHANCE FOR THEM THIS MORNING AND EARLY
AFTERNOON.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...JCB
LONG TERM...BILLINGS WRIGHT
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
949 AM EDT TUE APR 26 2016
.SYNOPSIS...
WARM WEATHER IS EXPECTED THROUGH FRIDAY. A COLD FRONT WILL BRING
SHOWERS THURSDAY INTO THURSDAY NIGHT. HIGH PRESSURE WILL BUILD IN
ON SATURDAY BRINGING A BIT OF A COOLDOWN. RAIN CHANCES RAMP UP ON
SUNDAY AND WILL PERSIST FOR THE FEW DAYS THAT FOLLOW.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM TUESDAY...EXPANSIVE SURFACE HIGH PRESSURE CENTERED
WELL OFF THE MID-ATLANTIC COAST WILL CONTINUE TO RIDGE BACK INTO
THE SOUTHEAST TODAY. THIS HIGH WILL BE THE CONTROLLING INFLUENCE
INTO OUR SENSIBLE WEATHER...KEEPING A SLOW MOVING COLD FRONT
STALLED WELL TO OUR NORTH ACROSS THE OH VLY AND INTO SOUTHERN NEW
ENGLAND.
RETURN FLOW AROUND THIS HIGH COMBINED WITH ZONAL FLOW ALOFT WILL
DRIVE TEMPS TO ABOVE CLIMO VALUES TODAY...WITH MID 80S EXPECTED
INLAND AND UPPER 70S ALONG THE IMMEDIATE COAST. THE COAST WILL BE
MUCH COOLER THANKS TO A STRONG SEA BREEZE FORECAST TO DEVELOP
EARLY THIS AFTERNOON...WITH S/SW WINDS INCREASING TO AROUND 15
MPH. THIS WILL ALSO DRIVE ENOUGH MOISTURE INTO THE COLUMN TO
PRODUCE WIDESPREAD BUT MOSTLY SHALLOW CUMULUS INLAND FROM THE SEA
BREEZE TODAY. LATEST HRRR AND ARW SUGGEST ISOLATED SHOWERS ARE
POSSIBLE...AND HAVE INCREASED POP FROM INHERITED...BUT MAINTAINED
VALUES BELOW MENTIONABLE DUE TO THE DRY AIR ALOFT AND A SUBSIDENCE
INVERSION AROUND 800MB. CANNOT RULE OUT A STRAY SHOWER TODAY BUT
FELT IT MORE ACCURATE TO KEEP POP SILENT ATTM.
A WARM AND HUMID NIGHT FORECAST AS WARM SW FLOW PERSISTS. MINS WILL
DROP ONLY INTO THE LOW AND MID 60S...WARMEST NEAR THE COAST...AND
A STRONG LLJ PREVENTS STEEPENING OF THE NOCTURNAL INVERSION.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM TUESDAY...EVEN THOUGH THE UPPER LEVEL RIDGE ACROSS
THE SE UNITED STATES WILL TECHNICALLY REMAIN IN PLACE WEDNESDAY
AND THURSDAY...IT WILL GET BEATEN DOWN BY SEVERAL SHORTWAVE
DISTURBANCES. SURFACE HIGH PRESSURE WILL REMAIN WELL OFF THE EAST
COAST...FEEDING HEAT AND MOISTURE NORTHWARD FROM FLORIDA.
WITH INLAND HIGHS REACHING THE MID 80S BOTH DAYS...SURFACE-BASED
INSTABILITY SHOULD REACH 1000 J/KG WEDNESDAY AND MAY APPROACH 1500
J/KG ON THURSDAY. THIS SHOULD LEAD TO IMPRESSIVE CUMULUS GROWTH AND
SOME OF THE FIRST AIRMASS THUNDERSTORMS OF THE YEAR. THESE STORMS
SHOULD CONCENTRATE ALONG THE SEABREEZE BOUNDARY BOTH DAYS AND ALSO
AHEAD OF AN UPPER DISTURBANCE MOVING OVERHEAD THURSDAY. FORECAST
POPS ARE AROUND 20 PERCENT WEDNESDAY AND 40 PERCENT ON THURSDAY.
A COLD FRONT DROPPING SOUTH FROM NEW ENGLAND SHOULD MAY MAKE IT AS
FAR SOUTH AS NORTHEASTERN NORTH CAROLINA ON WEDNESDAY. THIS BOUNDARY
WILL REMAIN NEARLY STATIONARY THROUGH THURSDAY...BUT RECENT MODELS
ARE SUGGESTING IT MAY SAG SOUTH INTO SOUTHEASTERN NORTH CAROLINA
THURSDAY NIGHT. SHOULD THIS OCCUR IT COULD LEAD AN ENHANCEMENT IN
SHOWER AND THUNDERSTORM COVERAGE. CONFIDENCE IN THE MOVEMENT OF THIS
BOUNDARY IS LOWER THAN NORMAL GIVEN THAT ITS POSITION WEDNESDAY AND
THURSDAY WILL BE HEAVILY INFLUENCED BY UPSTREAM THUNDERSTORMS ACROSS
VIRGINIA AND NORTHERN NORTH CAROLINA...NONE OF WHICH HAVE DEVELOPED
YET.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 300 AM TUESDAY...COOL FRONT PUSHES THROUGH EARLY FRIDAY AND
TAKES ANY MOISTURE ALONG WITH IT. TEMPERATURES LIKELY TO REMAIN
ABOVE CLIMO THOUGH AS THE MAIN COOL PUSH IS DELAYED UNTIL FRIDAY
NIGHT WITH THE PASSAGE OF A WAVE OFF MID ATLANTIC COAST. THIS
SECONDARY PUSH WILL BRING SEASONABLE TEMPERATURES BACK BY SATURDAY
AS HIGH PRESSURE RIDGES IN FROM THE NORTH. WARM FRONT LIFTS BACK
THROUGH TO THE NORTH ON SUNDAY AND CONSIDERABLE MOISTURE RETURN
APPEARS TO ACCOMPANY AND FOLLOW ITS PASSAGE. FOR THE REMAINDER OF
THE PERIOD THE UPPER RIDGE BREAKS DOWN AND A VERY POSITIVELY
TILTED TROUGH HANGS UP TO OUR WEST. THIS WILL KEEP US IN A VORT-
LADEN SOUTHWESTERLY FLOW ATOP INCREASING GULF MOISTURE FOR SOME
RATHER UNSETTLED WEATHER.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
AS OF 12Z...EXPECT VFR THROUGH THE VALID TAF PERIOD AS HIGH PRESSURE
REMAINS JUST OFFSHORE.
POTENTIAL FOR LIGHT PATCHY FOG THIS MORNING...BUT CONFIDENCE IS
LOW THUS HAVE NOT INTRODUCED INTO GOING FORECAST. LIGHT WINDS WILL
BECOME SOUTHWESTERLY AND INCREASE TO AOB 10 KTS LATER THIS
MORNING. ANTICIPATE SOUTHERLY FLOW TO INCREASE ALONG THE COAST
THIS AFTERNOON WITH WINDS OF 10 TO 20 KTS. ANY MID TO HIGH CLOUD
DEVELOPMENT TODAY WILL REMAIN FEW/SCT IN NATURE. GUSTS WILL
SUBSIDE THIS EVENING AND SOUTHWESTERLY WINDS AOB 10 KTS WILL
CONTINUE OVERNIGHT.
EXTENDED OUTLOOK...ISOLATED SHOWERS POSSIBLE WED AFTERNOON WITH
BETTER CHANCES THURSDAY AND FRIDAY. OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM TUESDAY...HIGH PRESSURE CENTERED WELL OFF THE COAST
WILL DRIFT SLOWLY MORE TO THE EAST THROUGH TONIGHT. THIS WILL
CONTINUE S/SW WINDS ACROSS THE WATERS...WITH SPEEDS INCREASING TO
AROUND 15 KTS. A STRONG SEA BREEZE CIRCULATION IS FORECAST THIS
AFTN AND EVENING...SO WINDS WITHIN THE NEAR SHORE WATERS MAY BACK
A BIT TO THE SOUTH AND GUST TO 20 KTS AT TIMES...BEFORE THE
SYNOPTIC FLOW AGAIN BECOMES PREDOMINANT TONIGHT. SEAS CURRENTLY
AROUND 2-3 FEET MAY LOCALLY BUILD TO 3-4 FEET IN SPOTS TONIGHT IN
A COMBINATION OF ENE SWELL AND LOCAL SHORT PERIOD WIND CHOP.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM TUESDAY...HIGH PRESSURE WILL REMAIN WELL OFF THE EAST
COAST. A COLD FRONT PUSHING SOUTH FROM NEW ENGLAND WILL MAKE IT AS
FAR SOUTH AS NORTHEASTERN NORTH CAROLINA WEDNESDAY. THE FRONT SHOULD
THEN BECOME NEARLY STATIONARY THROUGH THURSDAY AS WAVES OF LOW
PRESSURE RIPPLE ALONG IT. MODELS ARE BECOMING A LITTLE MORE EMPHATIC
THAT THE FRONT MAY PUSH SOUTH INTO SE NORTH CAROLINA THURSDAY NIGHT.
THE TIMING OF THIS FRONTAL PASSAGE IS VERY UNCERTAIN...PARTICULARLY
SINCE MOST MODELS PAINT MULTIPLE CLUSTERS OF THUNDERSTORMS ALONG THE
FRONT THURSDAY AND THURSDAY NIGHT. OUTSIDE OF THUNDERSTORMS THE
STRONGEST SYNOPTIC WIND SPEEDS ARE EXPECTED BOTH WEDNESDAY AND
THURSDAY AFTERNOONS IN ASSOCIATION WITH THE DAILY SEABREEZE
CIRCULATION.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 300 AM TUESDAY...COLD FRONT COMES THROUGH EARLY FRIDAY
LEAVING MUCH OF THE DAY WITH LIGHT AND VARIABLE WINDS. A SECONDARY
PUSH OF HIGH PRESSURE COMES IN FROM THE NORTH FRIDAY NIGHT INTO
SATURDAY TURNING THE WINDS TO NORTHEAST. THE HIGH REMAINS WELL TO
OUR NORTH ON SATURDAY NIGHT AS IT PROGRESSES EASTWARD. LOCALLY
THIS TURNS THE FLOW TO SOUTHEASTERLY OR EVEN SOUTHERLY. DURING ALL
OF THESE DIRECTIONAL CHANGES WIND SPEEDS WILL BE CAPPED IN THE 10
TO 15 KT RANGE. SO WHILE WAVE PERIODS MAY BE UNPLEASANTLY SHORT
AND CHOPPY THERE WILL NOT BE MUCH OVERALL BUILDING OF DOMINANT
WAVE HEIGHTS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...JDW
SHORT TERM...TRA
LONG TERM...MBB
AVIATION...SGL
MARINE...
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
630 AM EDT TUE APR 26 2016
.SYNOPSIS...
COLD FRONT SINKS SOUTH INTO OUR FORECAST AREA TODAY. FRONT WAFFLES
BACK/FORTH IN OUR VICINITY THROUGH THURSDAY NIGHT...PROVIDING FOR
ROUNDS OF SHOWERS AND THUNDERSTORMS.
&&
.NEAR TERM /THROUGH TONIGHT/...
630 AM UPDATE...
LINE ON CONVECTION WILL BRUSH OUR NORTHERN COUNTIES THIS MORNING
WITH SOME THUNDERSTORMS. LINE IS MOVING FAIRLY QUICKLY SO DO NOT
EXPECT IT TO POSE TOO MUCH OF A THREAT...MAINLY A BRIEF PERIOD OF
RAIN WITH SOME SMALL HAIL AND A WIND GUST. HRRR IS NOT LATCHING
ONTO THE FEATURE VERY WELL. OVERALL ENVIRONMENT AHEAD OF THIS LINE
OF THUNDERSTORMS IS NOT TOO IMPRESSIVE YET...SO BELIEVE IT WILL
WEAKEN OVER THE NEXT FEW HOURS AS IT MOVES INTO THE MTNS.
MAIN FEATURE TODAY WILL BE THE COLD FRONT SINKING DOWN FROM THE
NORTH. THIS WILL INCREASE CLOUDS AND INSTABILITY FOR SCT
THUNDERSTORMS TODAY. THIS AFTERNOON...THERE IS A LITTLE BIT OF
SEVERE POTENTIAL WITH THE STORMS WITH 1000+ J/KG CAPE...35 KT OF
DEEP LAYER SHEAR...AND 250 M2/S2 OF SRH COULD PRODUCE A FEW
ROTATING STORMS WITH THE BIGGEST SEVERE THREAT BEING HAIL/WIND.
SPC HAS US MARGINALLY RISKED WHICH SEEMS LIKE A FAIR ASSESSMENT.
THE FRONT LAYS OUT TONIGHT BUT WILL KEEP INCLEMENT WEATHER AROUND
THE AREA THROUGH MUCH OF THE WEEK.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
MODELS ARE STRUGGLING WITH THIS PATTERN...PROVIDING VARIOUS
SOLUTIONS. THIS LEADS TO LOW CONFIDENCE IN THE TIMING OF VARIOUS
FEATURES AND ASSOCIATED ROUNDS OF SHOWERS AND THUNDERSTORMS. WILL
LOWER POPS WEDNESDAY NIGHT TO REFLECT THIS UNCERTAINTY. WILL ALSO
KEEP THE CURRENT FORECAST FROM THURSDAY NIGHT ONWARD FOR
CONSISTENCY...ESPECIALLY CONSIDERING THAT CONFIDENCE IN ANY ONE
SOLUTION IS NOT HIGH.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
MODELS IN AGREEMENT WITH LOW PRESSURE MOVING THROUGH THE AREA ON
FRIDAY AND EXITING OFF THE ATLANTIC COAST LATE FRIDAY NIGHT. ANY
SHOWERS WILL EXIT WITH THIS SYSTEM. SATURDAY LOOKS TO BE THE
BEST DAY OUT OF THE WEEKEND WITH WEAK RIDGING TAKING HOLD.
SUNDAY THROUGH MONDAY IS WHERE THE CONFIDENCE OF THE FORECAST
DIMINISHES. BOTH THE GFS AND ECMWF DEVELOP SYSTEM OUT TO OUR
WEST, BUT TIMING AND POSITION OF THE SYSTEMS DIFFER. THE GFS
BRINGS A WARM FRONTAL BOUNDARY UP ACROSS THE AREA AND DEVELOPS A
LOW PRESSURE SYSTEM THAT TRACKS ACROSS THE SOUTHERN PORTION OF THE
CWA. THE ECMWF DEVELOPS THE LOW AND TRACKS IT NORTH OF THE CWA
THROUGH MONDAY. IN ANY CASE THERE WILL BE SHOWERS AROUND. WITH
THIS SCENARIO, INTRODUCE LIKELY POPS OVER MUCH OF THE AREA ON
SUNDAY AND KEPT CHANCE POPS EVERYWHERE MONDAY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AROUND 30 KT OF LLWS THIS MORNING AS LOW LEVEL JET SNEAKS IN WITH
LOWER ATMOSPHERE DECOUPLED. VFR THOUGH MVFR/IFR CONDITIONS
IN SHOWERS OR STORMS TODAY. MVFR OR IFR CONDITIONS ARE EXPECTED
BEHIND THE FRONT TONIGHT INTO WEDNESDAY.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z WEDNESDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: COVERAGE OF SHOWERS COULD BE MORE THAN
EXPECTED. IFR MAY BE A POSSIBILITY IN WAKE OF FRONT AS DEEP LOW
LEVEL SATURATION OCCURS.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
EDT 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
CRW CONSISTENCY H H H H H H H M M M M M
HTS CONSISTENCY H H H H H H H M M M M M
BKW CONSISTENCY H H H H H H H H H H M M
EKN CONSISTENCY H H H H H H H M M M M M
PKB CONSISTENCY H H H H H M M M M M M M
CKB CONSISTENCY H H H H H M M H H M M M
AFTER 12Z WEDNESDAY...
IFR POSSIBLE IN ROUNDS OF SHOWERS OR STORMS THROUGH THURSDAY. LOW
CEILINGS MAY ALSO FORM WEDNESDAY MORNING NORTH OF THE STALLED
FRONT.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JS/RPY/JW
NEAR TERM...JW
SHORT TERM...RPY
LONG TERM...JS
AVIATION...JW
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1055 AM EDT TUE APR 26 2016
.SYNOPSIS...
A COLD FRONT WILL DROP ACROSS THE REGION THIS AFTERNOON. A LARGE
AREA OF HIGH PRESSURE OVER SOUTH CENTRAL CANADA WILL RIDGE
SOUTHEAST ACROSS THE GREAT LAKES AND INTO PENNSYLVANIA WEDNESDAY
INTO THURSDAY WITH FAIR AND COOLER CONDITIONS. ANOTHER AREA OF LOW
PRESSURE TRACK SOUTH OF PENNSYLVANIA THURSDAY INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
REMNANT SHOWERS FROM DISSIPATING MCS ARE NOW EXITING SOUTHERN
LANCASTER AND YOR COUNTIES. FOCUS SHIFTS UPSTREAM TO SECONDARY
CONVECTIVE DEVELOPMENT ALONG BAROCLINIC ZONE SAGGING ESE ACROSS
CENTRAL AND SOUTH CENTRAL PA THIS AFTERNOON. HI RES CAMS INDICATE
A BROKEN LINE OF CONVECTION WITH ISOLATED TO SCATTERED COVERAGE
ACCOMPANYING THIS BOUNDARY AS IT DROPS SOUTHWARD BETWEEN 16Z AND
22Z...AND WE`RE OUTLOOKED IN MRGL/SLGT RSK BY SPC WITH ISOLD
MUCAPES UP TO 1500 J/KG. WEAK CIN IN THE 0-1 KM LAYER COMPLICATES
THINGS AND DEGRADES CONFIDENCE SOMEWHAT GIVEN THE LACK OF UPPER
LEVEL FORCING...BUT STILL ON THE LOOKOUT FOR ISOLATED TO
SCATTERED COVERAGE OF SHOWERS ALONG WITH A FEW STORMS WHICH COULD
PRODUCE MARGINAL PULSE WIND GUSTS.
THE SFC FRONTAL WAVE ITSELF TRACKS ALONG THE PA/NY BORDER THIS
AFTERNOON...WITH ITS SOUTHWESTWARD TRAILING COLD FRONT SETTLING
ACROSS THE COMMONWEALTH LATE THIS AFTERNOON AND THIS EVENING.
TIMING OF PRECIP/CONVECTION WILL BE TIED TO THIS FEATURE...WITH
SHRA/TSRA MOST LIKELY FROM 18Z TO 22Z.
SPC`S DAY 1 MARGINAL AND SLGT RISK AREAS COVER THE SE HALF OF
PENN. STRONG WESTERLY WIND GUSTS ATTRIBUTED TO 30-50 KT WINDS IN
THE 850-700 MB LAYER...AND AN INVERTED-V SOUNDING...ARE THE MAIN
THREAT.
COOLER AIR IS OVERSPREADING THE NORTHWEST AFTERNOON. HIGHS THERE
ONLY REACH NEAR 60F. FARTHER SOUTH ANOTHER WARM DAY WILL BE SEEN
WITH HIGHS IN THE MID TO UPPER 70S FOR ONE MORE DAY ACROSS SOUTH
CENTRAL AND SOUTHEAST PA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
LATEST...07Z HRRR IMPLIES THAT THE SFC COLD FRONT WILL SLIDE
SOUTH OF THE I-76/78 CORRIDOR BEFORE DUSK...WITH LINGERING
SHOWERS AND TSRA NEAR THE MASON/DIXON LINE INTO THIS EVENING.
A SEVERAL HOUR PERIOD OF BKN-OVC STRATUS AND STRATO CU SHOULD
FOLLOW THE CFROPA THROUGH LATE THIS EVENING...BEFORE DRIER AIR
PUSHES IN FROM THE NORTH/NORTHEAST AND HELPS TO ERODE THE LOW CLOUD
DECK.
LOW TEMPS TONIGHT WILL RANGE FROM THE FROSTY LOWER 30S ACROSS THE
NORTHERN TIER COUNTIES...TO THE MID AND UPPER 40S IN THE SOUTH.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
WED LOOKS DRY AND COOLER...AS A NE FLOW OF DRY AIR BUILDS
SOUTHWARD FROM A LARGE HIGH OVER WESTERN HUDSON BAY.
A SYSTEM TRACKING SOUTH OF THE AREA ON THU WILL BRING SOME
RAIN...AND MORE NOTABLY COOLER TEMPERATURES TO THE AREA.
A SECOND WEAK SYSTEM TRACKING SOUTH OF THE AREA OUT OF WV MAY
BRING SOME SHOWERS STILL ON FRIDAY. LEFT POPS IN.
STILL SOME HINTS OF A JET MAX DROPPING SE ON SAT...BUT REALLY
NO MOISTURE TO WORK WITH. THUS STILL EXPECT THE DAY TO BE DRY.
MID SHIFT HAD SOME SHOWERS IN FOR LATER ON SUNDAY. YESTERDAY THE
EC WAS TOO FAST...STILL THAT WAY TODAY. LEFT POPS IN BUT DID LOWER
SOME FOR SUNDAY AND SUNDAY NIGHT.
FOR SUNDAY NIGHT..DID EDGE TEMPERATURES DOWN A LITTLE.
LOOKS WET AND COOL FOR MONDAY. DID NOT GO QUITE AS HIGH AS
THE SUPERBLEND WITH THE POPS.
CLEARING OUT LATER MONDAY NIGHT.
OVERALL A PATTERN THAT FAVORS WETTER AND COOLER WEATHER
THAN WE HAVE HAD LATELY.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
A MINIMUM OF SHOWER ACTIVITY PERSISTS THROUGH MIDDAY...
BUT CONVECTION WILL REDEVELOP AND EXPAND OVER CENTRAL MTNS AND
DROP ACROSS SOUTHERN SECTIONS IN THE AFTERNOON AS A COLD FRONT
DROPS ACROSS THE STATE. CAPE INCREASES MIDDAY...WHICH WILL BRING
SCT TSTMS AS WELL.
PRECIP WILL END FROM NW TO SE...EXITING THE LOWER SUSQ SHORTLY
AFTER 00Z WED. LOWERING CIGS WILL SAG IN FROM THE
NORTH...IMPACTING MAINLY WESTERN HIGHER TERRAIN AND LIKELY
EXPANDING INTO THE CENTRAL MTNS TONIGHT.
OUTLOOK...
WED...NO SIG WX EXPECTED.
THU-FRI...MVFR WITH SHRA LIKELY.
SAT...FAIR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DEVOIR/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/MARTIN
AVIATION...DEVOIR/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
743 AM EDT TUE APR 26 2016
.SYNOPSIS...
LOW PRESSURE OVER SOUTHERN MICHIGAN WILL MOVE EAST AND TRACK
OVER NRN PA/WRN NY STATE TODAY. THIS LOW WILL PUSH A COLD FRONT
THROUGH THE AREA TODAY. A LARGE AREA OF HIGH PRESSURE OVER SOUTH
CENTRAL CANADA WILL RIDGE SOUTHEAST ACROSS THE GREAT LAKES AND
INTO PENNSYLVANIA WEDNESDAY INTO THURSDAY WITH FAIR AND COOLER
CONDITIONS. ANOTHER AREA OF LOW PRESSURE TRACK SOUTH OF
PENNSYLVANIA THURSDAY INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SUBSTANTIALLY WEAKENED MCS HEADED ACROSS THE ALLEGHENY PLATEAU OF
NRN AND WRN PENN AT 1030Z. THIS FEATURE WILL SPREAD SHOWERS AND A
FEW BRIEF...LOW-TOPPED TSRA ACROSS THE CENTRAL MTNS AND SUSQ
VALLEY DURING THE MID TO LATE MORNING HOURS TODAY.
SFC COLD FRONT EXTENDING FROM LOW PRESSURE NEAR DETROIT WILL
BE LAGGING THIS MCS BY SEVERAL HOURS. DEWPOINTS WILL RECOVER INTO
THE MID AND UPPER 50S ACROSS SOUTHERN PENN THIS AFTERNOON...AND
THEY WILL COMBINE WITH PARTLY SUNNY SKIES AND MDTLY STRONG DEEP
LAYER WESTERLY SHEAR TO PRODUCE A RISK OF STRONG TO SEVERE TSRA
DURING THE EARLY TO MID AFTERNOON HOURS OVER THE SERN HALF OF THE
STATE.
THE SFC FRONTAL WAVE TRACKS ALONG THE PA/NY BORDER THIS
AFTERNOON...WITH ITS SOUTHWESTWARD TRAILING COLD FRONT SETTLING
ACROSS THE COMMONWEALTH LATE THIS AFTERNOON AND THIS EVENING.
A SECOND ROUND OF CONVECTION SHOULD REFIRE DURING THE LATE
MORNING AND EARLY AFTERNOON HOURS ACROSS CENTRAL AND WESTERN
PENN...THEN STEADILY EXPAND TO THE ESE ACROSS THE LOWER/MID SUSQ
VALLEY AND SOUTHERN TIER OF PENN AS THE MILDER AND MORE UNSTABLE
AIR PUSHES NORTHEAST OUT OF THE OHIO VALLEY.
A 2-3 SIGMA 850MB WESTERLY JET WILL SLIDE ACROSS THE SOUTHERN
HALF OF PENN THROUGH THE MIDDAY HOURS...AND WILL SUPPORT AN
INITIALLY COMPACT AREA OF 3-4 SIGMA 850 MB MOISTURE FLUX. THIS
AREA OF BETTER MOISTURE AND STRONGER FORCING WILL COVER ABOUT THE
SE THIRD OF THE STATE AT 18Z.
POCKETS OF MDTLY HIGH ML CAPES OF 1000-1500 J/KG WILL DEVELOP DURING
THE LATE MORNING AND AFTERNOON HOURS ACROSS THE SOUTHERN THIRD OF
THE STATE...WHILE MUCH MORE STABLE AIR ADVECTS INTO THE NRN MTNS.
SPC`S DAY 1 MARGINAL RISK AREA COVERS THE SE HALF OF PENN...BUT
UPGRADED FAR SERN PENN (INCLUDING YORK AND LANCASTER COUNTIES) TO
A SLIGHT RISK WITH THE MAIN SEVERE WEATHER THREAT COMING IN THE
FORM OF ISOLATED STRONG/DAMAGING WESTERLY WIND GUSTS ATTRIBUTED TO
30-50 KT WINDS IN THE 850-700 MB LAYER...AND AN INVERTED-V
SOUNDING. MODELS SHOWING LOCAL PREFRONTAL 1000 J/KG CAPES ALONG
THE MASON-DIXON LINE LATER THIS MORNING/AFTN.
TOTAL FCST RAINFALL FROM ABOUT MIDNIGHT MONDAY NIGHT THROUGH 6 PM
TODAY WAS PAINTED TO BE A BIT HIGHER THAN A GEFS/SREF
BLEND ACROSS APPROX THE SOUTHERN HALF OF THE CWA...GIVEN THE 6
HOURLY TOTALS THAT OCCURRED WITH THE MCS NOW TRACKING ACROSS
WESTERN LAKE ERIE AND FAR NWRN OHIO.
COOL AIR REACHES THE NORTHWEST BY LATE THIS MORNING...WITH HIGHS
THERE ONLY REACHING NEAR 60F. FARTHER SOUTH ANOTHER WARM DAY WILL
BE SEEN WITH HIGHS IN THE MID TO UPPER 70S FOR ONE MORE DAY ACROSS
SOUTH CENTRAL AND SOUTHEAST PA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
LATEST...07Z HRRR IMPLIES THAT THE SFC COLD FRONT WILL SLIDE
SOUTH OF THE I-76/78 CORRIDOR BEFORE DUSK...WITH LINGERING
SHOWERS AND TSRA NEAR THE MASON/DIXON LINE INTO THIS EVENING.
A SEVERAL HOUR PERIOD OF BKN-OVC STRATUS AND STRATO CU SHOULD
FOLLOW THE CFROPA THROUGH LATE THIS EVENING...BEFORE DRIER AIR
PUSHES IN FROM THE NORTH/NORTHEAST AND HELPS TO ERODE THE LOW CLOUD
DECK.
LOW TEMPS TONIGHT WILL RANGE FROM THE FROSTY LOWER 30S ACROSS THE
NORTHERN TIER COUNTIES...TO THE MID AND UPPER 40S IN THE SOUTH.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
WED LOOKS DRY AND COOLER...AS A NE FLOW OF DRY AIR BUILDS
SOUTHWARD FROM A LARGE HIGH OVER WESTERN HUDSON BAY.
A SYSTEM TRACKING SOUTH OF THE AREA ON THU WILL BRING SOME
RAIN...AND MORE NOTABLY COOLER TEMPERATURES TO THE AREA.
A SECOND WEAK SYSTEM TRACKING SOUTH OF THE AREA OUT OF WV MAY
BRING SOME SHOWERS STILL ON FRIDAY. LEFT POPS IN.
STILL SOME HINTS OF A JET MAX DROPPING SE ON SAT...BUT REALLY
NO MOISTURE TO WORK WITH. THUS STILL EXPECT THE DAY TO BE DRY.
MID SHIFT HAD SOME SHOWERS IN FOR LATER ON SUNDAY. YESTERDAY THE
EC WAS TOO FAST...STILL THAT WAY TODAY. LEFT POPS IN BUT DID LOWER
SOME FOR SUNDAY AND SUNDAY NIGHT.
FOR SUNDAY NIGHT..DID EDGE TEMPERATURES DOWN A LITTLE.
LOOKS WET AND COOL FOR MONDAY. DID NOT GO QUITE AS HIGH AS
THE SUPERBLEND WITH THE POPS.
CLEARING OUT LATER MONDAY NIGHT.
OVERALL A PATTERN THAT FAVORS WETTER AND COOLER WEATHER
THAN WE HAVE HAD LATELY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
FIRST WAVE SLIDING THROUGH BRINGING AN ERODING AREA OF SHOWERS
/AND EARLIER ISO THUNDER TO FAR WESTERN SECTIONS/. CONDITIONS
REMAINING GENERALLY VFR ACROSS CENTRAL PA THOUGH VSBYS HAVE
SLIPPED TO MVFR FOR A SHORT TIME IN THE EAST.
EXPECT A MINIMUM OF SHOWER ACTIVITY MID/LATE MORNING...BUT
CONVECTION SHOULD STEADILY EXPAND OVER CENTRAL MTNS AND DROP
ACROSS SOUTHERN SECTIONS IN THE AFTERNOON AS A COLD FRONT DROPS
ACROSS THE STATE. CAPE INCREASES MIDDAY...WHICH WILL BRING SCT
TSTMS AS WELL.
PRECIP WILL END FROM NW TO SE...EXITING THE LOWER SUSQ SHORTLY
AFTER 00Z WED. LOWERING CIGS WILL SAG IN FROM THE
NORTH...IMPACTING MAINLY WESTERN HIGHER TERRAIN AND LIKELY
EXPANDING INTO THE CENTRAL MTNS TONIGHT.
OUTLOOK...
WED...NO SIG WX EXPECTED.
THU-FRI...MVFR WITH SHRA LIKELY.
SAT...FAIR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/MARTIN
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
655 AM EDT TUE APR 26 2016
.SYNOPSIS...
LOW PRESSURE OVER SOUTHERN MICHIGAN WILL MOVE EAST AND TRACK
OVER NRN PA/WRN NY STATE TODAY. THIS LOW WILL PUSH A COLD FRONT
THROUGH THE AREA TODAY. A LARGE AREA OF HIGH PRESSURE OVER SOUTH
CENTRAL CANADA WILL RIDGE SOUTHEAST ACROSS THE GREAT LAKES AND
INTO PENNSYLVANIA WEDNESDAY INTO THURSDAY WITH FAIR AND COOLER
CONDITIONS. ANOTHER AREA OF LOW PRESSURE TRACK SOUTH OF
PENNSYLVANIA THURSDAY INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SUBSTANTIALLY WEAKENED MCS HEADED ACROSS THE ALLEGHENY PLATEAU OF
NRN AND WRN PENN AT 1030Z. THIS FEATURE WILL SPREAD SHOWERS AND A
FEW BRIEF...LOW-TOPPED TSRA ACROSS THE CENTRAL MTNS AND SUSQ
VALLEY DURING THE MID TO LATE MORNING HOURS TODAY.
SFC COLD FRONT EXTENDING FROM LOW PRESSURE NEAR DETROIT WILL
BE LAGGING THIS MCS BY SEVERAL HOURS. DEWPOINTS WILL RECOVER INTO
THE MID AND UPPER 50S ACROSS SOUTHERN PENN THIS AFTERNOON...AND
THEY WILL COMBINE WITH PARTLY SUNNY SKIES AND MDTLY STRONG DEEP
LAYER WESTERLY SHEAR TO PRODUCE A RISK OF STRONG TO SEVERE TSRA
DURING THE EARLY TO MID AFTERNOON HOURS OVER THE SERN HALF OF THE
STATE.
THE SFC FRONTAL WAVE TRACKS ALONG THE PA/NY BORDER THIS
AFTERNOON...WITH ITS SOUTHWESTWARD TRAILING COLD FRONT SETTLING
ACROSS THE COMMONWEALTH LATE THIS AFTERNOON AND THIS EVENING.
A SECOND ROUND OF CONVECTION SHOULD REFIRE DURING THE LATE
MORNING AND EARLY AFTERNOON HOURS ACROSS CENTRAL AND WESTERN
PENN...THEN STEADILY EXPAND TO THE ESE ACROSS THE LOWER/MID SUSQ
VALLEY AND SOUTHERN TIER OF PENN AS THE MILDER AND MORE UNSTABLE
AIR PUSHES NORTHEAST OUT OF THE OHIO VALLEY.
A 2-3 SIGMA 850MB WESTERLY JET WILL SLIDE ACROSS THE SOUTHERN
HALF OF PENN THROUGH THE MIDDAY HOURS...AND WILL SUPPORT AN
INITIALLY COMPACT AREA OF 3-4 SIGMA 850 MB MOISTURE FLUX. THIS
AREA OF BETTER MOISTURE AND STRONGER FORCING WILL COVER ABOUT THE
SE THIRD OF THE STATE AT 18Z.
POCKETS OF MDTLY HIGH ML CAPES OF 1000-1500 J/KG WILL DEVELOP DURING
THE LATE MORNING AND AFTERNOON HOURS ACROSS THE SOUTHERN THIRD OF
THE STATE...WHILE MUCH MORE STABLE AIR ADVECTS INTO THE NRN MTNS.
SPC`S DAY 1 MARGINAL RISK AREA COVERS THE SE HALF OF PENN...BUT
UPGRADED FAR SERN PENN (INCLUDING YORK AND LANCASTER COUNTIES) TO
A SLIGHT RISK WITH THE MAIN SEVERE WEATHER THREAT COMING IN THE
FORM OF ISOLATED STRONG/DAMAGING WESTERLY WIND GUSTS ATTRIBUTED TO
30-50 KT WINDS IN THE 850-700 MB LAYER...AND AN INVERTED-V
SOUNDING. MODELS SHOWING LOCAL PREFRONTAL 1000 J/KG CAPES ALONG
THE MASON-DIXON LINE LATER THIS MORNING/AFTN.
TOTAL FCST RAINFALL FROM ABOUT MIDNIGHT MONDAY NIGHT THROUGH 6 PM
TODAY WAS PAINTED TO BE A BIT HIGHER THAN A GEFS/SREF
BLEND ACROSS APPROX THE SOUTHERN HALF OF THE CWA...GIVEN THE 6
HOURLY TOTALS THAT OCCURRED WITH THE MCS NOW TRACKING ACROSS
WESTERN LAKE ERIE AND FAR NWRN OHIO.
COOL AIR REACHES THE NORTHWEST BY LATE THIS MORNING...WITH HIGHS
THERE ONLY REACHING NEAR 60F. FARTHER SOUTH ANOTHER WARM DAY WILL
BE SEEN WITH HIGHS IN THE MID TO UPPER 70S FOR ONE MORE DAY ACROSS
SOUTH CENTRAL AND SOUTHEAST PA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
LATEST...07Z HRRR IMPLIES THAT THE SFC COLD FRONT WILL SLIDE
SOUTH OF THE I-76/78 CORRIDOR BEFORE DUSK...WITH LINGERING
SHOWERS AND TSRA NEAR THE MASON/DIXON LINE INTO THIS EVENING.
A SEVERAL HOUR PERIOD OF BKN-OVC STRATUS AND STRATO CU SHOULD
FOLLOW THE CFROPA THROUGH LATE THIS EVENING...BEFORE DRIER AIR
PUSHES IN FROM THE NORTH/NORTHEAST AND HELPS TO ERODE THE LOW CLOUD
DECK.
LOW TEMPS TONIGHT WILL RANGE FROM THE FROSTY LOWER 30S ACROSS THE
NORTHERN TIER COUNTIES...TO THE MID AND UPPER 40S IN THE SOUTH.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
WED LOOKS DRY AND COOLER...AS A NE FLOW OF DRY AIR BUILDS
SOUTHWARD FROM A LARGE HIGH OVER WESTERN HUDSON BAY.
A SYSTEM TRACKING SOUTH OF THE AREA ON THU WILL BRING SOME
RAIN...AND MORE NOTABLY COOLER TEMPERATURES TO THE AREA.
A SECOND WEAK SYSTEM TRACKING SOUTH OF THE AREA OUT OF WV MAY
BRING SOME SHOWERS STILL ON FRIDAY. LEFT POPS IN.
STILL SOME HINTS OF A JET MAX DROPPING SE ON SAT...BUT REALLY
NO MOISTURE TO WORK WITH. THUS STILL EXPECT THE DAY TO BE DRY.
MID SHIFT HAD SOME SHOWERS IN FOR LATER ON SUNDAY. YESTERDAY THE
EC WAS TOO FAST...STILL THAT WAY TODAY. LEFT POPS IN BUT DID LOWER
SOME FOR SUNDAY AND SUNDAY NIGHT.
FOR SUNDAY NIGHT..DID EDGE TEMPERATURES DOWN A LITTLE.
LOOKS WET AND COOL FOR MONDAY. DID NOT GO QUITE AS HIGH AS
THE SUPERBLEND WITH THE POPS.
CLEARING OUT LATER MONDAY NIGHT.
OVERALL A PATTERN THAT FAVORS WETTER AND COOLER WEATHER
THAN WE HAVE HAD LATELY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
SFC FRONTAL WAVE TRACKS ALONG THE PA/NY BORDER THIS MORNING...
BEFORE SAGGING SOUTHWARD AS COLD FRONT SETTLES ACROSS THE
COMMONWEALTH LATER IN THE DAY.
OVERNIGHT...GENERALLY VFR CONDITIONS PERSISTING AREAWIDE...EXCEPT
IN SCT SHOWERS/VERY ISOLATED TSTMS MAINLY NORTH OF I-80. MORE
WIDESPREAD SHOWERS WILL IMPACT NW PORTIONS AFTER 09Z AS WESTERLY LLJET
SWINGS THROUGH.
EXPECT A BIT OF A MINIMUM OF SHOWER ACTIVITY MID/LATE
MORNING...BUT CONVECTION SHOULD STEADILY EXPAND OVER CENTRAL MTNS
AND EXPAND INTO SOUTHERN MTNS IN THE AFTERNOON AS MORE UNSTABLE
AIR PUSHES NE OUT OF THE OHIO VALLEY.
PRECIP WILL END FROM NW TO SE...EXITING THE LOWER SUSQ SHORTLY
AFTER 00Z WED. LOWERING CIGS WILL SAG IN FROM THE
NORTH...IMPACTING MAINLY WESTERN HIGHER TERRAIN AND LIKELY
EXPANDING INTO THE CENTRAL MTNS TUE NIGHT.
OUTLOOK...
WED...NO SIG WX EXPECTED.
THU-FRI...MVFR WITH SHRA LIKELY.
SAT...FAIR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/MARTIN
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1100 AM CDT TUE APR 26 2016
.UPDATE...
INCREASED POPS ACROSS NORTHERN PORTIONS OF THE MID SOUTH LATE THIS
AFTERNOON INTO THIS EVENING.
&&
.DISCUSSION...
LOW LEVEL MOISTURE CONTINUES TO SURGE NORTHWARD INTO THE MID SOUTH
THIS MORNING...ACCOMPANIED BY LOW LEVEL STRATUS DECK ACROSS THE
WESTERN HALF OF THE AREA. THIS LOW LEVEL CLOUD COVER SHOULD MIX
OUT BY LATE MORNING IN MOST AREAS...WHICH WILL ALLOW TEMPERATURES
TO RISE INTO THE LOWER AND MIDDLE 80S BY THIS AFTERNOON ALONG WITH
MIDDLE TO UPPER 60S DEWPOINTS.
REVIEW OF THE 12Z REGIONAL SOUNDING DATA SUGGESTS STRONGER CAPPING
WITHIN THE 850-700 MB LAYER TO THE SOUTHWEST (KLZK...KSHV). THE
CAPPING IS WEAKER TO THE NORTHEAST AS SUGGESTED BY THE 12Z KOHX
SOUNDING. REGIONAL RADAR SHOWS A MESOSCALE CONVECTIVE SYSTEM
(MCS) MOVING THROUGH CENTRAL MISSOURI LATE THIS MORNING AND
PROPAGATING QUICKLY TO THE SOUTHEAST. INSTABILITY ACROSS NORTHERN
PORTIONS OF THE MID SOUTH SHOULD INCREASE SUBSTANTIALLY BY THIS
AFTERNOON IN A WEAKLY CAPPED ENVIRONMENT. LATEST MODEL GUIDANCE
SUGGESTS SBCAPES RISING BETWEEN 2000-3000 J/KG WITH MID LEVEL
LAPSE RATES BETWEEN 7.5-8.0 C/KM AND LI/S AROUND -8C. AS THE
FORWARD PROPAGATING MCS CONVECTION MOVES INTO NORTHERN AREAS EARLY
THIS EVENING...A FEW STORMS MAY REMAIN SEVERE WITH THE POTENTIAL
FOR DAMAGING WINDS AND LARGE HAIL. CONVECTION SHOULD DIMINISH IN
INTENSITY AND COVERAGE WITH SOUTHWARD EXTENT THROUGH THE EVENING
AS MID LEVEL CAPPING NEGATIVELY INFLUENCES CONVECTION. PLAN TO
INCLUDE SLIGHT RISK MENTION FOR SEVERE STORMS ACROSS NORTHERN
AREAS FOR LATE THIS AFTERNOON AND EVENING.
STORMS SHOULD DIMINISH ENTIRELY BY LATE EVENING PRIOR TO REACHING
THE INTERSTATE 40 CORRIDOR.
UPDATED ZONES...GRIDS...AND HAZARDOUS WEATHER OUTLOOK WILL BE SENT
OUT SHORTLY.
JLH
&&
.PREV DISCUSSION... /ISSUED 308 AM CDT TUE APR 26 2016/
SKIES WERE GENERALLY CLEAR ACROSS THE MIDSOUTH WITH PATCHY
STRATOCU IN NORTH CENTRAL ARKANSAS STARTING TO BLEED INTO THE
WESTERN COUNTIES. TEMPERATURES WERE IN THE 60S WITH SOUTH WINDS
RUNNING 5 TO 10 MPH. THOUGH THE MIDSOUTH WAS FREE OF
CONVECTION...STORMS NEAR THE KANSAS CITY METRO ALONG A STATIONARY
FRONT ARE FORMING AHEAD OF SCHEDULE COMPARED TO THE HRRR MODEL.
FOR TODAY AND TOMORROW...BREEZY SOUTH WINDS AHEAD OF A DEVELOPING
STORM IN THE PLAINS WILL CONTINUE TO PUMP GULF MOISTURE INTO THE
MIDSOUTH...WITH DEWPOINTS CLIMBING INTO THE MID AND UPPER 60S BY
THIS AFTERNOON. THIS COUPLED WITH TEMPERATURES IN THE LOW TO MID
80S WILL GENERATE A FAIR AMOUNT OF CUMULUS AND CAPE VALUES NEAR
3000 J/KG. HOWEVER THE CLOSEST TRIGGER TO INITIATE STORMS WILL
LIE WITH HOW THE ABOVE MENTIONED CONVECTION IN MISSOURI UNFOLDS.
HRRR AND NAM MODELS SUGGEST THIS ACTIVITY WILL PROPAGATE EAST
SOUTHEAST ALONG THE FRONT AS IT PUSHES INTO THE LOWER OHIO VALLEY.
A STRONG ENOUGH AND PERSISTENT ENOUGH OUTFLOW FROM THIS MCS COULD
FIRE STORMS LATE THIS AFTERNOON AND EVENING ALONG THE FAR NORTHERN
MIDSOUTH COUNTIES...OF WHICH SOME COULD BE STRONG OR SEVERE GIVEN
THE ANTICIPATED CAPE. FOR NOW WILL PASS THE POTENTIAL ON TO THE
DAYCREW. BETTER CHANCES FOR STORMS WILL ARRIVE LATER TONIGHT AS
CONVECTION MARCHES EAST OUT OF OKLAHOMA AND TEXAS. THIS ACTIVITY
MAY ALSO MAINTAIN A FAIR AMOUNT OF INTENSITY AS IT WILL BE LINKED
TO THE SUPPORTING NEGATIVE TILTED SHORTWAVE. MODELS SHOW THE
LEADING EDGE REACHING THE MISSISSIPPI RIVER NEAR DAYBREAK AND THE
TENNESSEE RIVER BY NOON. AFTER WHICH QUESTIONS ARISE WITH THE
AMOUNT OF LINGERING CLOUD COVER AND THUS THE ABILITY FOR THE
ATMOSPHERE TO SOMEWHAT RELOAD. MODELS SHOW A WEAKER WAVE SWINGING
THROUGH THE OZARKS IN THE 26/0Z TO 26/06Z TIME FRAME THAT MAY BE
ENOUGH FOR AT LEAST ISOLATED STORMS FROM LATE IN THE AFTERNOON
THROUGH THE EVENING. LOW LEVEL SHEAR WILL HAVE WEAKEN ATT...ALONG
WITH RISING HEIGHT FALLS...AS BOTH THE UPPER AND LOW LEVEL SYSTEM
BEGIN FILLING. THE ONLY CAVEAT WILL BE MIDLEVEL LAPSE RATES WILL
FALL TO NEAR 8C...WHICH WOULD LEAD TO A LARGE HAIL THREAT. CHANCES
FOR RAIN WILL DIMINISH FROM WEST TO EAST LATE TOMORROW NIGHT.
HIGHS TODAY WILL BE IN THE LOW TO MID 80S WITH TEMPERATURES
RUNNING ABOUT FIVE DEGREES COOLER TOMORROW. LOWS IN THE 60S.
THURSDAY AND FRIDAY...DRY INITIALLY WITH WEAK LOW LEVEL FLOW AND
A CONTINUANCE OF ABOVE NORMAL TEMPERATURES. A SECOND STORM SYSTEM
WILL DEVELOP IN THE SOUTHERN ROCKIES...SURGING MOISTURE AND
ENERGY BACK INTO THE OZARKS AND LOWER MISSISSIPPI VALLEY BY FRIDAY
AFTERNOON. SHOWERS AND STORMS WILL OVERSPREAD THE AREA FRIDAY NIGHT.
SATURDAY THROUGH MONDAY NIGHT...A GENERALLY WET PERIOD AS THE
UPPER LOW IN THE FOUR CORNERS TAKES A SIMILAR TRACK...AND TIMING
AS THE CURRENT FRONT RANGE LOW. THIS WOULD PLACE THE MAIN JET
CORRIDOR FROM TEXAS TO THE OHIO VALLEY. ROUNDS OF
CONVECTION...WITH SOME STORMS POTENTIALLY SEVERE APPEAR
FAVORABLE...AS WELL AS A THREAT FOR PERIODS OF HEAVIER RAINFALL.
HIGH TEMPERATURES WILL RUN CLOSE TO NORMAL WITH ABOVE NORMAL LOWS.
JAB
&&
.AVIATION...12Z TAF CYCLE
VFR CONDITIONS WILL PERSIST TODAY AND MOST OF THE NIGHT BEFORE
SHOWERS AND THUNDERSTORMS MOVE IN LATE TONIGHT. WINDS WILL BE
SOUTHERLY THROUGH THE PERIOD...INCREASING TO 8-12KT TODAY...LIKELY
REMAINING AROUND 10 KT TONIGHT.
INCLUDED VCTS AT MKL AND MEM AFTER 10Z WITH CIGS OF 4000FT. STORMS
LOOK LIKELY A BIT EARLIER AT JBR...POSSIBLY AS EARLY AS 07Z.
INCLUDED PREVAILING -TSRA WITH 3SM VIS AFTER 10Z. CIGS SHOULD BE
AROUND 4000FT.
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
626 AM CDT TUE APR 26 2016
.UPDATE...AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 308 AM CDT TUE APR 26 2016/
SKIES WERE GENERALLY CLEAR ACROSS THE MIDSOUTH WITH PATCHY
STRATOCU IN NORTH CENTRAL ARKANSAS STARTING TO BLEED INTO THE
WESTERN COUNTIES. TEMPERATURES WERE IN THE 60S WITH SOUTH WINDS
RUNNING 5 TO 10 MPH. THOUGH THE MIDSOUTH WAS FREE OF
CONVECTION...STORMS NEAR THE KANSAS CITY METRO ALONG A STATIONARY
FRONT ARE FORMING AHEAD OF SCHEDULE COMPARED TO THE HRRR MODEL.
FOR TODAY AND TOMORROW...BREEZY SOUTH WINDS AHEAD OF A DEVELOPING
STORM IN THE PLAINS WILL CONTINUE TO PUMP GULF MOISTURE INTO THE
MIDSOUTH...WITH DEWPOINTS CLIMBING INTO THE MID AND UPPER 60S BY
THIS AFTERNOON. THIS COUPLED WITH TEMPERATURES IN THE LOW TO MID
80S WILL GENERATE A FAIR AMOUNT OF CUMULUS AND CAPE VALUES NEAR
3000 J/KG. HOWEVER THE CLOSEST TRIGGER TO INITIATE STORMS WILL
LIE WITH HOW THE ABOVE MENTIONED CONVECTION IN MISSOURI UNFOLDS.
HRRR AND NAM MODELS SUGGEST THIS ACTIVITY WILL PROPAGATE EAST
SOUTHEAST ALONG THE FRONT AS IT PUSHES INTO THE LOWER OHIO VALLEY.
A STRONG ENOUGH AND PERSISTENT ENOUGH OUTFLOW FROM THIS MCS COULD
FIRE STORMS LATE THIS AFTERNOON AND EVENING ALONG THE FAR NORTHERN
MIDSOUTH COUNTIES...OF WHICH SOME COULD BE STRONG OR SEVERE GIVEN
THE ANTICIPATED CAPE. FOR NOW WILL PASS THE POTENTIAL ON TO THE
DAYCREW. BETTER CHANCES FOR STORMS WILL ARRIVE LATER TONIGHT AS
CONVECTION MARCHES EAST OUT OF OKLAHOMA AND TEXAS. THIS ACTIVITY
MAY ALSO MAINTAIN A FAIR AMOUNT OF INTENSITY AS IT WILL BE LINKED
TO THE SUPPORTING NEGATIVE TILTED SHORTWAVE. MODELS SHOW THE
LEADING EDGE REACHING THE MISSISSIPPI RIVER NEAR DAYBREAK AND THE
TENNESSEE RIVER BY NOON. AFTER WHICH QUESTIONS ARISE WITH THE
AMOUNT OF LINGERING CLOUD COVER AND THUS THE ABILITY FOR THE
ATMOSPHERE TO SOMEWHAT RELOAD. MODELS SHOW A WEAKER WAVE SWINGING
THROUGH THE OZARKS IN THE 26/0Z TO 26/06Z TIME FRAME THAT MAY BE
ENOUGH FOR AT LEAST ISOLATED STORMS FROM LATE IN THE AFTERNOON
THROUGH THE EVENING. LOW LEVEL SHEAR WILL HAVE WEAKEN ATT...ALONG
WITH RISING HEIGHT FALLS...AS BOTH THE UPPER AND LOW LEVEL SYSTEM
BEGIN FILLING. THE ONLY CAVEAT WILL BE MIDLEVEL LAPSE RATES WILL
FALL TO NEAR 8C...WHICH WOULD LEAD TO A LARGE HAIL THREAT. CHANCES
FOR RAIN WILL DIMINISH FROM WEST TO EAST LATE TOMORROW NIGHT.
HIGHS TODAY WILL BE IN THE LOW TO MID 80S WITH TEMPERATURES
RUNNING ABOUT FIVE DEGREES COOLER TOMORROW. LOWS IN THE 60S.
THURSDAY AND FRIDAY...DRY INITIALLY WITH WEAK LOW LEVEL FLOW AND
A CONTINUANCE OF ABOVE NORMAL TEMPERATURES. A SECOND STORM SYSTEM
WILL DEVELOP IN THE SOUTHERN ROCKIES...SURGING MOISTURE AND
ENERGY BACK INTO THE OZARKS AND LOWER MISSISSIPPI VALLEY BY FRIDAY
AFTERNOON. SHOWERS AND STORMS WILL OVERSPREAD THE AREA FRIDAY NIGHT.
SATURDAY THROUGH MONDAY NIGHT...A GENERALLY WET PERIOD AS THE
UPPER LOW IN THE FOUR CORNERS TAKES A SIMILAR TRACK...AND TIMING
AS THE CURRENT FRONT RANGE LOW. THIS WOULD PLACE THE MAIN JET
CORRIDOR FROM TEXAS TO THE OHIO VALLEY. ROUNDS OF
CONVECTION...WITH SOME STORMS POTENTIALLY SEVERE APPEAR
FAVORABLE...AS WELL AS A THREAT FOR PERIODS OF HEAVIER RAINFALL.
HIGH TEMPERATURES WILL RUN CLOSE TO NORMAL WITH ABOVE NORMAL LOWS.
JAB
&&
.AVIATION...12Z TAF CYCLE
VFR CONDITIONS WILL PERSIST TODAY AND MOST OF THE NIGHT BEFORE
SHOWERS AND THUNDERSTORMS MOVE IN LATE TONIGHT. WINDS WILL BE
SOUTHERLY THROUGH THE PERIOD...INCREASING TO 8-12KT TODAY...LIKELY
REMAINING AROUND 10 KT TONIGHT.
INCLUDED VCTS AT MKL AND MEM AFTER 10Z WITH CIGS OF 4000FT. STORMS
LOOK LIKELY A BIT EARLIER AT JBR...POSSIBLY AS EARLY AS 07Z.
INCLUDED PREVAILING -TSRA WITH 3SM VIS AFTER 10Z. CIGS SHOULD BE
AROUND 4000FT.
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1015 AM EDT TUE APR 26 2016
.SYNOPSIS...
FRONT WITH WAVES OF LOW PRESSURE EXTENDED FROM NEW JERSEY TO
MISSOURI THIS MORNING. THIS FRONT WILL DRIFT SOUTH THEN STALL OVER
THE MID ATLANTIC REGION ON WEDNESDAY. ANOTHER LOW PRESSURE SYSTEM
WILL TRACK FROM THE MID MISSISSIPPI VALLEY TO THE EAST COAST ON
THURSDAY AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1015 AM EDT TUESDAY...
AREA OF CONVECTION TO THE SOUTH OF THE FRONTAL BOUNDARY CONTINUES
TO DRIFT SOUTHEASTWARD THROUGH NRN WEST VIRGINIA...AND MAY BRUSH
THE FAR NRN PORTION OF OUR FCST AREA BETWEEN 11AM AND NOON BEFORE
DISSIPATING. HOWEVER THIS SHOULD LEAVE AN OUTFLOW BOUNDARY TO AID
IN THE DEVELOPMENT OF MORE CONVECTION BY MID TO LATE AFTERNOON.
FARTHER SOUTH IT LOOKS LIKE SOME WEAK SUBSIDENCE WILL PREVENT MORE
THAN ISOLATED SHWRS OR THUNDERSTORMS TO FORM...AND THESE WOULD BE
CONFINED TO MTNS...BUT BEST CHANCES WILL BE LATE AFTERNOON INTO
EARLY EVENING MAINLY NORTH OF U.S. 460. ONE OR TWO OF THE
CONVECTIVE RESOLVING MODELS DO SUGGESTS A BROKEN LINE WILL MAKE IT
DOWN TO AT LEAST THE NORTH CAROLINA BORDER BY LATE EVENING...BUT
AM SKEPTICAL OF THESE ARE WILL AWAIT 12Z UPDATES TO SOME OF THESE
BEFORE REFINING FORECAST FURTHER. FOR NOW HAVE REDUCED POPS
FARTHER SOUTH AND SLOWED DOWN TIMING OF ARRIVAL OF THES SCATTERED
STORMS. STILL EXPECTING SOME ISOLATED SEVERE THREAT NORTH OF 460
AND MAINLY WEST OF BLUE RIDGE...WITH WIND DAMAGE BEING MOST LIKELY
CONCERN GIVEN DRY AIR ALOFT TO SUPPORT DOWNDRAFTS AND MODEST LOW
LEVEL WIND SHEAR TO ALLOW FOR SOME DEGREE OF ORGANIZATION. CANNOT
RULE OUT A HAIL THREAT BUT INSTABILITY IS NOT ESPECIALLY HIGH AND
WARM BOUNDARY LAYER TEMPS WILL HELP WITH MELTING.
PREV DISCUSSION AS OF 355 AM EDT TUESDAY...
LOW PRESSURE OVER MICHIGAN WILL MOVE EAST ALONG A FRONT INTO
EASTERN PENNSYLVANIA TODAY. THEN THE FRONT WILL MOVE SOUTH INTO
THE MID ATLANTIC REGION LATE TODAY INTO TONIGHT. THE SURFACE
BOUNDARY REACHES THE FORECAST AREA AFTER 00Z/8PM...WHILE THE
850MB FRONT STAYS WELL TO THE NORTH. STARTING OUT WITH LITTLE
CLOUD COVER THIS MORNING SO TEMPERATURES WILL WARM QUICKLY AFTER
SUNRISE. WITH SURFACE DEW POINTS IN THE 50S...CONVECTIVE AVAILABLE
POTENTIAL ENERGY WAS FORECAST TO BE AROUND 1500 J/KG THIS
AFTERNOON AHEAD OF THE FRONT. SOME GUIDANCE SUGGESTED POOLING OF
DEW POINTS IN THE LOWER 60S JUST AHEAD OF THE BOUNDARY WHICH WOULD
RESULT IN EVEN LARGER CAPE. 00Z NAM AS WELL AS THE RAP AND LOCAL
WRF HAVE A BULK OF THE PRECIPITATION THAT WILL BE AHEAD OF THE
FRONT REACHING THE NORTHERN COUNTY WARNING AREA JUST AFTER
18Z/2PM. BETTER COVERAGE OF SHOWERS AND THUNDERSTORMS MAY NOT
PROGRESS SOUTH...REACHING THE VIRGINIA/NORTH CAROLINA BORDER UNTIL
AROUND 00Z/8PM. BETTER VORTICITY ADVECTION AND JET SUPPORT REACH
THE FORECAST AREA TONIGHT SO HAVE INCREASED THE PROBABILITY OF
PRECIPITATION FOR TONIGHT.
GUIDANCE WAS TOO COOL FOR MAXIMUM TEMPERATURES ON MONDAY. HAVE
GONE CLOSER TO WARMER GUIDANCE AND PERSISTENCE FROM MONDAY FOR
MAXIMUM TEMPERATURES TODAY. CLOUDS AND MILD DEW POINTS WILL KEEP
TEMPERATURES FROM DROPPING MUCH OVERNIGHT. HAVE RAISED MINIMUM
TEMPERATURES SLIGHTLY ACROSS THE PIEDMONT TONIGHT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
AS OF 330 AM EDT TUESDAY...
THE UPPER LEVEL PATTERN WILL REMAIN UNSETTLED AS THE WESTERN TROF
SPLINTERS INTO PIECES WITH SEVERAL BITS OF SHORT WAVE ENERGY MOVING IN
OUR DIRECTION INTERSPERSED WITH PERIODS OF GENERALLY FLAT RIDGING. AND
WITHOUT SOLID UPPER LEVEL SUPPORT TO MOVE IT ALONG...THE FRONTAL ZONE
AT THE SURFACE WILL SIMPLY LINGER OVER THE REGION THROUGH THE END OF
THE WEEK. AMPLE CONVERGENCE AND INSTABILITY IN THE FRONTAL ZONE WILL
KEEP UP WITH A CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY. BY FRIDAY
IT APPEARS THAT A SHORT WAVE REMNANT OF THE WESTERN TROF WILL SWING BY
TO OUR NORTH AND HELP PUSH THE FRONTAL BOUNDARY FURTHER TO THE SOUTH
AND ALLOW A WEDGE OF HIGH PRESSURE TO BUILD DOWN EAST OF THE
APPALACHIANS. HOWEVER ANY IMPROVEMENT IN OUR WEATHER LOOK TO BE
MARGINAL SINCE CLOUDS AND SOME LIGHT PRECIPITATION WILL ACCOMPANY THE
WEDGE. TEMPERATURES WILL GENERALLY BE A BIT ABOVE NORMAL THROUGH THE
END OF THE WEEK WITH HIGHS IN THE MID 70S TO AROUND 80 EAST OF THE BLUE
RIDGE...AND IN THE LOW TO MID 70S WEST.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 245 PM EDT MONDAY...
WEAK UPPER RIDGING THROUGH SATURDAY WILL KEEP PRECIP CHANCES CONFINED
TO ISOLATED/WIDELY SCATTERED IN COVERAGE. AT THE SFC...12Z ECMWF KEEPS
WEDGE IN PLACE THROUGH SATURDAY. WHILE TEMPS WERE BROUGHT DOWN A COUPLE
OF DEGREES DURING THIS TIME...THESE FORECAST VALUES STILL MAY BE TOO
WARM.
HOWEVER...BETTER CHANCES FOR MORE WIDESPREAD PRECIPITATION
ARRIVE LATER SUNDAY INTO MONDAY...DEPENDING ON THE ARRIVAL OF AN
OPENING UPPER LOW MOVING THROUGH THE OHIO VALLEY. AS IT TYPICAL
FOR THE LONG RANGE MODELS...THERE IS DISAGREEMENT IN THE TIMING
AND TRACK OF THIS SYSTEM...BUT INDIVIDUAL GEFS ENSEMBLE MEMBERS
SUGGEST THE BEST CHANCES FOR PRECIPITATION WILL BE LATE SUNDAY
INTO EARLY MONDAY...AND THIS IS THE TIME PERIOD WHERE THE POPS ARE
HIGHEST.
TEMPS ARE EXPECTED TO BE BELOW NORMAL EARLY WITH THE WEDGE IN
PLACE TO NEAR NORMAL LATER IN THE LONG TERM PERIOD.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
AS OF 720 AM EDT TUESDAY...
A COLD FRONT EXTENDED FROM PENNSYLVANIA TO MISSOURI THIS MORNING.
THIS FRONT WILL MOVE SOUTH INTO THE MID ATLANTIC REGION TODAY.
WITH THE BOUNDARY IN THE AREA AND MOISTURE ON THE INCREASE...SCATTERED
SHOWERS AND THUNDERSTORM WITH MVFR CEILINGS AND VISIBILITIES WILL
DEVELOP THIS AFTERNOON...MAINLY ACROSS THE MOUNTAINS. BY THE LATE
MORNING SURFACE WIND GUSTS WILL BE IN THE 15 TO 20 KT RANGE.
MODELS BRING THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS INTO THE
AREA AFTER 3PM IN KLWB AND NOT UNTIL 5PM AT KDAN. MEDIUM
CONFIDENCE ON THE TIMING OF THE PRECIPITATION AND ON THE
OCCURRENCE OF AN ADDITIONAL PRECIPITATION OVERNIGHT.
EXTENDED AVIATION DISCUSSION...
THIS FRONT WILL REMAIN STALLED OVERHEAD WEDNESDAY...BEFORE A
STRONGER COLD FRONT ENTERS FROM THE WEST TO PUSH THE WEAKER FRONT
OFFSHORE. DURING THIS TIME...SCATTERED SHOWERS WITH A FEW
AFTERNOON THUNDERSTORMS APPEAR LIKELY. THE GREATEST CHANCE OF RAIN
AND MVFR/IFR CONDITIONS WILL ACCOMPANY THE STRONGER COLD FRONT ON
THURSDAY. SOME CLEARING SHOULD TAKE PLACE DURING FRIDAY...ALTHOUGH
A FEW MOUNTAIN SHOWERS AND MVFR CLOUDS ARE POSSIBLE.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...PH
LONG TERM...PH
AVIATION...AMS/DS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
725 AM EDT TUE APR 26 2016
.SYNOPSIS...
FRONT WITH WAVES OF LOW PRESSURE EXTENDED FROM NEW JERSEY TO
MISSOURI THIS MORNING. THIS FRONT WILL DRIFT SOUTH THEN STALL OVER
THE MID ATLANTIC REGION ON WEDNESDAY. ANOTHER LOW PRESSURE SYSTEM
WILL TRACK FROM THE MID MISSISSIPPI VALLEY TO THE EAST COAST ON
THURSDAY AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 355 AM EDT TUESDAY...
LOW PRESSURE OVER MICHIGAN WILL MOVE EAST ALONG A FRONT INTO
EASTERN PENNSYLVANIA TODAY. THEN THE FRONT WILL MOVE SOUTH INTO
THE MID ATLANTIC REGION LATE TODAY INTO TONIGHT. THE SURFACE
BOUNDARY REACHES THE FORECAST AREA AFTER 00Z/8PM...WHILE THE
850MB FRONT STAYS WELL TO THE NORTH. STARTING OUT WITH LITTLE
CLOUD COVER THIS MORNING SO TEMPERATURES WILL WARM QUICKLY AFTER
SUNRISE. WITH SURFACE DEW POINTS IN THE 50S...CONVECTIVE AVAILABLE
POTENTIAL ENERGY WAS FORECAST TO BE AROUND 1500 J/KG THIS
AFTERNOON AHEAD OF THE FRONT. SOME GUIDANCE SUGGESTED POOLING OF
DEW POINTS IN THE LOWER 60S JUST AHEAD OF THE BOUNDARY WHICH WOULD
RESULT IN EVEN LARGER CAPE. 00Z NAM AS WELL AS THE RAP AND LOCAL
WRF HAVE A BULK OF THE PRECIPITATION THAT WILL BE AHEAD OF THE
FRONT REACHING THE NORTHERN COUNTY WARNING AREA JUST AFTER
18Z/2PM. BETTER COVERAGE OF SHOWERS AND THUNDERSTORMS MAY NOT
PROGRESS SOUTH...REACHING THE VIRGINIA/NORTH CAROLINA BORDER UNTIL
AROUND 00Z/8PM. BETTER VORTICITY ADVECTION AND JET SUPPORT REACH
THE FORECAST AREA TONIGHT SO HAVE INCREASED THE PROBABILITY OF
PRECIPITATION FOR TONIGHT.
GUIDANCE WAS TOO COOL FOR MAXIMUM TEMPERATURES ON MONDAY. HAVE
GONE CLOSER TO WARMER GUIDANCE AND PERSISTENCE FROM MONDAY FOR
MAXIMUM TEMPERATURES TODAY. CLOUDS AND MILD DEW POINTS WILL KEEP
TEMPERATURES FROM DROPPING MUCH OVERNIGHT. HAVE RAISED MINIMUM
TEMPERATURES SLIGHTLY ACROSS THE PIEDMONT TONIGHT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
AS OF 330 AM EDT TUESDAY...
THE UPPER LEVEL PATTERN WILL REMAIN UNSETTLED AS THE WESTERN TROF
SPLINTERS INTO PIECES WITH SEVERAL BITS OF SHORT WAVE ENERGY MOVING IN
OUR DIRECTION INTERSPERSED WITH PERIODS OF GENERALLY FLAT RIDGING. AND
WITHOUT SOLID UPPER LEVEL SUPPORT TO MOVE IT ALONG...THE FRONTAL ZONE
AT THE SURFACE WILL SIMPLY LINGER OVER THE REGION THROUGH THE END OF
THE WEEK. AMPLE CONVERGENCE AND INSTABILITY IN THE FRONTAL ZONE WILL
KEEP UP WITH A CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY. BY FRIDAY
IT APPEARS THAT A SHORT WAVE REMNANT OF THE WESTERN TROF WILL SWING BY
TO OUR NORTH AND HELP PUSH THE FRONTAL BOUNDARY FURTHER TO THE SOUTH
AND ALLOW A WEDGE OF HIGH PRESSURE TO BUILD DOWN EAST OF THE
APPALACHIANS. HOWEVER ANY IMPROVEMENT IN OUR WEATHER LOOK TO BE
MARGINAL SINCE CLOUDS AND SOME LIGHT PRECIPITATION WILL ACCOMPANY THE
WEDGE. TEMPERATURES WILL GENERALLY BE A BIT ABOVE NORMAL THROUGH THE
END OF THE WEEK WITH HIGHS IN THE MID 70S TO AROUND 80 EAST OF THE BLUE
RIDGE...AND IN THE LOW TO MID 70S WEST.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 245 PM EDT MONDAY...
WEAK UPPER RIDGING THROUGH SATURDAY WILL KEEP PRECIP CHANCES CONFINED
TO ISOLATED/WIDELY SCATTERED IN COVERAGE. AT THE SFC...12Z ECMWF KEEPS
WEDGE IN PLACE THROUGH SATURDAY. WHILE TEMPS WERE BROUGHT DOWN A COUPLE
OF DEGREES DURING THIS TIME...THESE FORECAST VALUES STILL MAY BE TOO
WARM.
HOWEVER...BETTER CHANCES FOR MORE WIDESPREAD PRECIPITATION
ARRIVE LATER SUNDAY INTO MONDAY...DEPENDING ON THE ARRIVAL OF AN
OPENING UPPER LOW MOVING THROUGH THE OHIO VALLEY. AS IT TYPICAL
FOR THE LONG RANGE MODELS...THERE IS DISAGREEMENT IN THE TIMING
AND TRACK OF THIS SYSTEM...BUT INDIVIDUAL GEFS ENSEMBLE MEMBERS
SUGGEST THE BEST CHANCES FOR PRECIPITATION WILL BE LATE SUNDAY
INTO EARLY MONDAY...AND THIS IS THE TIME PERIOD WHERE THE POPS ARE
HIGHEST.
TEMPS ARE EXPECTED TO BE BELOW NORMAL EARLY WITH THE WEDGE IN
PLACE TO NEAR NORMAL LATER IN THE LONG TERM PERIOD.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 720 AM EDT TUESDAY...
A COLD FRONT EXTENDED FROM PENNSYLVANIA TO MISSOURI THIS MORNING.
THIS FRONT WILL MOVE SOUTH INTO THE MID ATLANTIC REGION TODAY.
WITH THE BOUNDARY IN THE AREA AND MOISTURE ON THE INCREASE...SCATTERED
SHOWERS AND THUNDERSTORM WITH MVFR CEILINGS AND VISIBILITIES WILL
DEVELOP THIS AFTERNOON...MAINLY ACROSS THE MOUNTAINS. BY THE LATE
MORNING SURFACE WIND GUSTS WILL BE IN THE 15 TO 20 KT RANGE.
MODELS BRING THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS INTO THE
AREA AFTER 3PM IN KLWB AND NOT UNTIL 5PM AT KDAN. MEDIUM
CONFIDENCE ON THE TIMING OF THE PRECIPITATION AND ON THE
OCCURRENCE OF AN ADDITIONAL PRECIPITATION OVERNIGHT.
EXTENDED AVIATION DISCUSSION...
THIS FRONT WILL REMAIN STALLED OVERHEAD WEDNESDAY...BEFORE A
STRONGER COLD FRONT ENTERS FROM THE WEST TO PUSH THE WEAKER FRONT
OFFSHORE. DURING THIS TIME...SCATTERED SHOWERS WITH A FEW
AFTERNOON THUNDERSTORMS APPEAR LIKELY. THE GREATEST CHANCE OF RAIN
AND MVFR/IFR CONDITIONS WILL ACCOMPANY THE STRONGER COLD FRONT ON
THURSDAY. SOME CLEARING SHOULD TAKE PLACE DURING FRIDAY...ALTHOUGH
A FEW MOUNTAIN SHOWERS AND MVFR CLOUDS ARE POSSIBLE.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...PH
LONG TERM...PH
AVIATION...AMS/DS
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
406 PM EDT TUE APR 26 2016
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTH OF OUR AREA THROUGH TONIGHT AND
WEDNESDAY MORNING AND THEN STALL. LOW PRESSURE WILL TRACK ALONG THIS
FRONT TO OUR SOUTH THURSDAY INTO FRIDAY. HIGH PRESSURE CENTERED NEAR
HUDSON BAY CANADA FRIDAY INTO SATURDAY WILL BUILD DOWN INTO OUR AREA
THROUGH MUCH OF SUNDAY. LOW PRESSURE THOUGH IN THE OHIO VALLEY
MONDAY SLOWLY MOVES CLOSER TO OUR AREA TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
19Z SURFACE ANALYSIS SHOWS A W-E ORIENTED COLD FRONT POSITIONED
ALONG THE I-80 CORRIDOR IN NRN PA AND NRN NJ. A WEAK WAVE OF LOW
PRESSURE AS LOCATED ALONG THE FRONT JUST TO THE NORTH OF PHILA.
MULTIPLE CONVECTIVE BANDS HAVE DEVELOPED ACROSS THE CENTRAL AND
NORTHERN TIER F THE CWA SO FAR THIS AFTERNOON.
BASED ON THE LATEST MESOANALYSIS AND RECENT SATELLITE/RADAR TRENDS,
POPS/WX WERE UPDATED TO BETTER TIME THE CONVECTION. OUR FORECAST
FOLLOWS THE HRRR CLOSELY AS IT HAD CAPTURED THE FASTER SOUTHWARD
PROGRESSION OF THE CONVECTION.
MESOANALYSIS SHOWS MODEST INSTABILITY WITH ABOUT 400-800 J/KG OF
MLCAPE SOUTH OF THE FRONT. EFFECTIVE BULK SHEAR PROFILES ARE 45-55
KT ACROSS THE AREA. COVERAGE/SEVERITY OF CONVECTION SHOULD BE
LIMITED WITH THE LARGER-SCALE LIFT WITH AN APPROACHING MID-LEVEL
SHORTWAVE TROUGH AND UPPER-LEVEL JET STREAK BEING SLIGHTLY REMOVED
NORTH (I-78 CORRIDOR NORTHWARD) OF WHERE THE BEST INSTABILITY
IS. NONETHELESS, THE ENVIRONMENT IS STILL SUPPORTIVE OF AT LEAST
ISOLATED SEVERE THUNDERSTORMS. SEVERE THUNDERSTORM WATCH 107 WAS
ISSUED AT 2 PM AND INCLUDES THE ENTIRE FORECAST AREA UNTIL 9 PM. NOT
MUCH HAS CHANGED IN OUR THINKING WITH REGARDS TO STORM MODE, COVERAGE
AND TIMING. THE MAIN THREAT IS STILL LOCALLY DAMAGING WINDS WITH THE
STRONGEST MULTI-CELL CLUSTERS. MARGINALLY SEVERE HAIL ALSO POSSIBLE.
SHOWERS EXPECTED TO LINGER OVERNIGHT ACROSS THE DELMARVA REGION WITH
THE FRONT SLOWING DOWN AS IT MOVES SOUTHWARD.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
THE COLD FRONT IS EXPECTED TO DECELERATE AS IT MOVES SOUTHWARD INTO
SRN VA AND NC ON WEDNESDAY. MEANWHILE, HIGH PRESSURE CENTERED NEAR
THE CANADIAN NORTHWEST PASSAGES WILL BUILD SEWD INTO THE NORTHEAST
STATES. THE LATEST GUIDANCE SHOWS DRIER AIR WITH THIS HIGH
ADVECTING SOUTH INTO THE LEHIGH VALLEY AND NW NJ DURING THE MORNING
BUT STRUGGLE TO ADVANCE FARTHER TO THE SOUTH DURING THE AFTERNOON.
THIS APPEARS A RESULT OF THE WINDS ACROSS SE PA/S NJ/DELMARVA REMAINING
VEERED OUT OF THE NE. FORECAST SOUNDINGS ACROSS THE SRN HALF OF
THE CWA, ESPECIALLY FROM THE 12Z NAM, INDICATE MOISTURE WILL
REMAIN TRAPPED UNDERNEATH THE BOUNDARY LAYER DUE TO ONSHORE FLOW
OFF THE OCEAN. THE MARINE STRATOCU WILL BE STUBBORN TO ERODE THE
FARTHER SOUTH YOU GO. HIGHS RANGE FROM THE MU50S IN THE DELMARVA
AND COASTAL NJ TO LM60S IN E PA AND IN C/NW NJ.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
THE SYNOPTIC PATTERN IS FORECAST TO BE COMPRISED OF A STRONG CLOSED
LOW NEAR THE CANADIAN MARITIMES WEDNESDAY NIGHT AND THURSDAY THAT
THEN SHIFTS EASTWARD. THIS ALLOWS CYCLONIC FLOW TO OCCUR ACROSS OUR
REGION FOR A TIME. THERE ARE SOME POCKETS OF ENERGY FORECAST TO
EVOLVE AROUND THIS LARGE TROUGH, ALLOWING LOW PRESSURE TO TRACK ALONG
A STALLED FRONTAL BOUNDARY TO OUR SOUTH THURSDAY THEN ANOTHER ONE
EARLY NEXT WEEK. THIS WILL LEAD TO SOME UNSETTLED WEATHER AT TIMES,
MOSTLY ON THURSDAY AND THEN AGAIN EARLY NEXT WEEK. THE AMOUNT OF
PRECIPITATION AND CLOUD COVER WILL IMPACT THE TEMPERATURES,
ESPECIALLY GIVEN THROUGH SUNDAY STRONG HIGH PRESSURE IS ANCHORED
WELL TO OUR NORTH. WE USED A MODEL/CONTINUITY BLEND THROUGH FRIDAY,
THEN BLENDED IN THE 12Z WPC GUIDANCE THEREAFTER. SOME ADJUSTMENTS
WERE THEN MADE FOLLOWING ADDITIONAL COLLABORATION WITH OUR
NEIGHBORING OFFICES.
FOR WEDNESDAY NIGHT AND THURSDAY...A POTENT CLOSED LOW CENTERED NEAR
THE CANADIAN MARITIMES WILL RESULT IN CYCLONIC FLOW ACROSS THE AREA.
A STALLED FRONT TO OUR SOUTH WILL CONTINUE WITH ENERGY TRAVERSING
IT, WITH THE MAIN ENERGY BACK INTO THE PLAINS. SURFACE HIGH PRESSURE
TRIES TO BUILD DOWN INTO OUR AREA AT FIRST, HOWEVER A LEAD IMPULSE
WILL DRIVE WAA AND OVERRUNNING INTO OUR AREA DURING THURSDAY.
HOWEVER, THERE IS SOME UNCERTAINTY ON THE NORTHERN EXTENT AND ALSO
COVERAGE OF THE SHOWERS ASSOCIATED WITH THIS GIVEN POTENTIALLY MUCH
DRIER AIR ADVECTING SOUTHWARD. LOOKS LIKE THE HIGHEST CHCS FOR
SHOWERS IS IN THE SOUTHERN HALF OF THE AREA AND THIS IS WHERE THE
HIGHEST POPS ARE CURRENTLY PLACED. GIVEN A NORTHEASTERLY LOW-
LEVEL FLOW AND THE PROSPECTS FOR A DECENT AMOUNT OF CLOUD COVER, WE
ARE ANTICIPATING THURSDAY TO BE ON THE COOL SIDE.
FOR FRIDAY THROUGH SUNDAY...SURFACE LOW FEATURE TO OUR SOUTH OVERALL
SHOULD BE SHIFTING OFFSHORE TO START FRIDAY. AS ADDITIONAL ENERGY
AMPLIFIES ACROSS THE PLAINS INTO SUNDAY, STRONG AND EXPANSIVE HIGH
PRESSURE AT THE SURFACE CENTERED NEAR HUDSON BAY WILL WEDGE DOWN
INTO OUR AREA ESPECIALLY SATURDAY AND MUCH OF SUNDAY. THIS WILL
RESULT IN NORTHEASTERLY FLOW OVERALL IN THE LOWER LEVELS, WITH COOL
TEMPERATURES CONTINUING ALTHOUGH SOME MODERATION SHOULD OCCUR
SUNDAY AWAY FROM THE COAST. LOW PRESSURE MIGRATING FROM THE CENTRAL
PLAINS TO THE UPPER OHIO VALLEY SUNDAY INTO MONDAY WILL PUSH A WARM
FRONT TOWARD OUR AREA LATER SUNDAY. SOME WAA AND ISENTROPIC LIFT MAY
BE ENOUGH TO PRODUCE SOME SHOWERS ESPECIALLY LATE SUNDAY.
FOR MONDAY AND TUESDAY...THE EVOLUTION OF AN INITIAL CLOSED LOW WELL
TO OUR WEST, AS IT MAY OPEN UP INTO THE EAST, DURING EARLY NEXT WEEK
WILL DETERMINE OUR SENSIBLE WEATHER. SOME GUIDANCE INDICATES A
FASTER EVOLUTION TO THIS FEATURE WHICH WOULD END ANY PRECIPITATION
CHCS SOONER. THE FLOW OVERALL LOOKS LIKE IT COULD BE BLOCKY ENOUGH
TO RESULT IN A SLOWER EASTWARD SHIFT OF THE SURFACE LOW, THEREFORE
WE FAVORED WPC GUIDANCE THAT SHOWS THE LOW ARRIVING DURING TUESDAY.
AS A RESULT, A POTENTIALLY UNSETTLED REGIME DURING THIS TIME
FRAME.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
SCT SHRA AND TSRA ALONG AND SOUTH OF A COLD FRONT ARE MOVING THRU THE
AREA THIS AFTN. A BRIEF PERIOD OF GUSTY NW WINDS AND IFR VSBY
RESTRICTIONS WILL OCCUR WHERE STORMS MOVE DIRECTLY OVER THE
TERMINALS.
FROPA WILL MOVE SOUTHWARD THRU THE AREA AND BE MARKED BY A WIND
SHIFT FROM W-SW TO N LATE THIS AFTN AND THEN NELY AFTER SUNSET.
MARINE STRATUS MAY MOVE INLAND WITH ONSHORE FLOW BEHIND THE FRONT.
ADDED MVFR CIGS TO THE TERMINALS FOR LATE THIS EVE AND OVERNIGHT.
IMPROVING TO VFR EVERYWHERE ON WEDNESDAY. NELY WINDS WILL BE
LIGHT.
OUTLOOK...
WEDNESDAY NIGHT AND THURSDAY...POTENTIALLY LOWERING TO MVFR/IFR
CONDITIONS ALONG WITH SHOWERS.
FRIDAY...MVFR CEILINGS POSSIBLE TO START, OTHERWISE VFR.
SATURDAY AND SUNDAY...VFR OVERALL, HOWEVER LOWER CEILINGS MAY
DEVELOP LATER SUNDAY WITH SOME SHOWERS.
&&
.MARINE...
SEVERE THUNDERSTORM WATCH IN EFFECT FOR THE WATERS THRU 9 PM. MAIN
THREAT IS STRONG WIND GUSTS.
SCA REMAINS IN EFFECT FOR THE DE BAY THRU THE REST OF THE AFTN WITH
W-SWLY WINDS GUSTING TO 25 KT. ADJACENT COASTAL AREAS WILL ALL SEE
GRADIENT WIND GUSTS 25 TO 30 KT. A BACKDOOR COLD FRONT HAS ALREADY
MADE IT INTO OUR NRN COASTAL WATERS. THE BOUNDARY WILL MOVE SWD THRU
THE AREA LATE THIS AFTN AND EVE. WINDS WILL SHIFT OUT OF THE NE
BEHIND IT. SCA CONTINUES FOR THE COASTAL WATERS THRU TONIGHT AS
A BRIEF NELY SURGE COULD PRODUCE GUSTS TO 25 KT IN THE COASTAL WATERS
TONIGHT. SEAS WILL BE 4-7 FT.
NELY WINDS DIMINISH ON WEDNESDAY. SEAS SHOULD DROP BELOW 5 FT BY
MORNING.
OUTLOOK...
WEDNESDAY NIGHT THROUGH SUNDAY...THE WINDS OVERALL ARE
ANTICIPATED TO BE BELOW 25 KNOTS, HOWEVER THE SEAS SHOULD BUILD
TO ABOUT 5 FEET ON THE ATLANTIC COASTAL WATERS THURSDAY
INTO THE WEEKEND WITH AN ONSHORE FLOW.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ430-
431.
&&
$$
SYNOPSIS...GORSE
NEAR TERM...KLEIN
SHORT TERM...KLEIN
LONG TERM...GORSE
AVIATION...GORSE/KLEIN
MARINE...GORSE/KLEIN
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
213 PM EDT TUE APR 26 2016
.SYNOPSIS...
A FRONTAL BOUNDARY LOCATED TO OUR NORTH WILL SLOWLY PUSH
SOUTHWARD ACROSS THE AREA TODAY AS AN AREA OF LOW PRESSURE MOVES
ALONG THE BOUNDARY. THE FRONT WILL PUSH SOUTH OF THE AREA
OVERNIGHT INTO WEDNESDAY MORNING AND STALL TO OUR SOUTH. ANOTHER
AREA OF LOW PRESSURE WILL MOVE ALONG THIS BOUNDARY TO OUR SOUTH
LATE THURSDAY INTO THURSDAY NIGHT. OUR AREA WILL REMAIN ON THE
SOUTHERN EDGE OF HIGH PRESSURE CENTERED ACROSS CENTRAL CANADA OVER
THE WEEKEND. AN AREA OF LOW PRESSURE AND ASSOCIATED FRONTAL
BOUNDARIES MAY AFFECT THE AREA EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SEVERE THUNDERSTORM WATCH 107 WAS ISSUED AT 2 PM AND INCLUDES THE
ENTIRE FORECAST AREA UNTIL 9 PM. NOT MUCH HAS CHANGED IN OUR
THINKING WITH REGARDS TO STORM MODE, COVERAGE AND TIMING. THE MAIN
THREAT IS STILL LOCALLY DAMAGING WINDS WITH THE STRONGEST MULTI-
CELL CLUSTERS. MARGINALLY SEVERE HAIL ALSO POSSIBLE.
PREVIOUS DISCUSSION...
13Z SURFACE ANALYSIS SHOWS A QUASI-STATIONARY FRONT ALONG THE NY-
PA, ARCING E-SEWD INTO THE NRN NJ. A WEAK AREA OF LOW PRESSURE
WAS NOTED ALONG THIS BOUNDARY NEAR BGM. LOOKING ALOFT, WATER VAPOR
SATELLITE IMAGERY SHOWS A SHORTWAVE TROUGH ASSOCIATED WITH THE
REMNANTS OF A MIDWEST MCS IS MOVING INTO E PA MID MORNING.
WEAKENING TRENDS WITH REGARDS TO THE CONVECTION CONTINUE TO BE
NOTED IN THE IR SATELLITE/ MOSAIC RADAR LOOP AS THIS SYSTEM MOVES
EASTWARD INTO OUR AREA THIS MORNING. THESE SHOWERS WILL MOVE THRU
THE SRN POCONOS AND NW NJ OVER OVER THE NEXT 1-2 HOURS. ELSEWHERE,
VIRTUALLY REMOVED THE MENTION OF PRECIP FROM THE FORECAST THRU
MIDDAY (THOUGH ISO SHOWERS WERE KEPT IN A FEW LOCATIONS AREAS).
LEFTOVER DEBRIS CLOUDS FROM THE REMNANT MCS WILL SWEEP THRU THE
AREA WHICH WILL DELAY STRONG SOLAR HEATING BY 2 OR 3 HOURS. MADE
ONLY SLIGHT MODIFICATIONS TO MAX TEMPS TODAY, TRYING TO SHOW A
TIGHT N-S TEMPERATURE GRADIENT ALONG THE I-80 CORRIDOR SINCE THIS
IS WHERE THE FRONT HAS STALLED. WE WERE CONSERVATIVE IN MAKING
UPWARD ADJUSTMENTS FOR HIGHS IN THE WARM SECTOR DUE TO THE MORNING
CLOUDS BUT HIGHS IN THE MID TO UPPER 80S ARE NOT OUT OF THE
QUESTION FROM PHILA SOUTHWARD IF WE CAN SEE AN EXTENDED PERIOD OF
SUNSHINE DURING PEAK HEATING THIS AFTERNOON.
BASED ON THE LATEST HI-RES CONVECTIVE-ALLOWING MODELS, HOURLY
POPS/WX WERE UPDATED FOR THIS AFTERNOON TO BETTER TIME THE
CONVECTION THAT IS EXPECTED TO DEVELOP ALONG THE FRONT AS IT
PROGRESSES SWD THRU THE AREA. FORECAST SOUNDINGS FROM THE NAM 4KM,
RAP AND HRRR SHOW MODEST INSTABILITY WITH ABOUT 600-1000 J/KG OF
MLCAPE DEVELOPING FROM SE PA-C NJ AND POINTS SWD BY MID TO LATE
AFTERNOON. FORECAST BULK SHEAR PROFILES INCREASE TO NEAR 50 KT
LATE THIS AFTERNOON AS A 65 KT MID-LEVEL JET STREAK SHIFTS
OVERHEAD. LARGER-SCALE LIFT DOES NOT LOOK QUITE AS FAVORABLE AS
IT ONCE DID IN EARLIER MODEL RUNS WITH THE DEEPEST LIFT FROM AN
APPROACHING MID-LEVEL SHORTWAVE TROUGH AND UPPER-LEVEL JET STREAK
SLIGHTLY REMOVED NORTH (ACROSS FAR NORTHERN PARTS OF THE CWA)
FROM WHERE THE STRONGEST DESTABILIZATION IS EXPECTED TO OCCUR THIS
AFTERNOON (ACROSS THE SOUTHERN HALF OF THE CWA). NONETHELESS,
THERE IS STILL ENOUGH INGREDIENTS AVAILABLE FOR AT LEAST SEVERAL
SEVERE THUNDERSTORMS TO DEVELOP. THE MAIN THREAT IS DAMAGING
WINDS BUT ISOLATED LARGE HAIL IS POSSIBLE. THE LATEST SPC D1
FORECAST EXPANDED THE SLIGHT RISK INTO MOST OF THE FORECAST AREA.
THE GREATEST RISK FOR SEVERE STORMS APPEARS TO BE FROM ABOUT 2-5
PM IN NE PA/NW NJ, 4-7 PM IN SE PA AND S NJ, 5-9 PM IN THE
DELMARVA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
THE COLD FRONT IS EXPECTED TO EXTEND THROUGH THE PHILADELPHIA
METROPOLITAN AREA AROUND 800 PM AND IT SHOULD REACH SOUTHERN
DELAWARE AND ITS ADJACENT COASTAL WATERS BY MIDNIGHT. THE ARRIVAL
OF THE FRONT SHOULD BRING AN END TO THE PRECIPITATION. HOWEVER,
CLOUDS ARE ANTICIPATED TO LINGER THROUGH MUCH OF THE NIGHT.
THE WIND SHOULD SETTLE INTO THE NORTH AND NORTHEAST BEHIND THE
COLD FRONT. TEMPERATURES ARE FORECAST TO DROP INTO THE 40S AND
50S.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
THE COLD FRONT WILL BECOME STATIONARY NEAR THE NC-VA BORDER
WEDNESDAY. DRIER AND COOLER AIR WILL WORKS ITS WAY INTO THE REGION
AS CANADIAN HIGH PRESSURE CENTERED NEAR THE NORTHWEST PASSAGES
RIDGES DOWN TOWARD US. HOWEVER, THE DRIER AIR MAY STRUGGLE TO MAKE
IT INTO OUR FAR SOUTHERN ZONES, RESULTING IN CLOUDY SKIES THAT
PERSIST INTO MOST OF WEDNESDAY ACROSS THE DELMARVA.
LEE CYCLOGENESIS IS CURRENTLY TAKING PLACE IN THE CO FRONT RANGE
OF THE ROCKIES. THIS SURFACE LOW WILL MEANDER OVER THE CENTRAL
PLAINS FOR THE NEXT FEW DAYS AS THE UPPER TROUGH TIED TO THE
SURFACE LOW REMAINS CUTS OFF. THE CUTOFF LOW IS FORECAST TO
EVENTUALLY WEAKEN AND BECOME AN OPEN WAVE BY THURSDAY. IN RESPONSE
TO THE EVOLVING UPPER PATTERN, THE SURFACE LOW WILL PROGRESS
EASTWARD ALONG THE STATIONARY BOUNDARY TO OUR SOUTH ON THURSDAY. A
SECONDARY WAVE OF LOW PRESSURE MAY DEVELOP AND RIDE THE FRONT ON
FRIDAY. OVERRUNNING PRECIP SHOULD EXPAND NORTHWARD LATE WEDNESDAY
NIGHT INTO THURSDAY AS THE FLOW BACKS MORE OUT OF THE SOUTH AHEAD
OF THE LOW AND ISENTROPIC LIFT STRENGTHENS ALONG AND ON THE COOL
SIDE OF THE BOUNDARY. THERE IS STILL UNCERTAINTY REGARDING HOW FAR
NORTH THE FRONT AND PRECIP ADVANCES WITH DRIER AIR BEING
REINFORCED BY HIGH PRESSURE ANCHORED TO OUR NORTH. THERE IS SOME
EVIDENCE FROM GUIDANCE THAT EVAPORATIVE COOLING AT THE ONSET COULD
LEAD TO A COLD AIR DAMMING PATTERN IF THERE IS ENOUGH LOW-LEVEL
DRY AIR IN PLACE WHEN THE OVERRUNNING PRECIP MOVES IN. THIS WOULD
KEEP THE FORECAST AREA ON THE COLD SIDE OF THE BOUNDARY. WE WILL
CONTINUE TO SHOW THE HIGHEST POPS ACROSS OUR SOUTHERN AREAS DUE TO
THE PROXIMITY OF THE FRONT.
THERE COULD CONTINUE TO BE SOME SHOWERS DURING THE DAY FRIDAY AS A
SHORT WAVE PUSHES ACROSS THE AREA AND THE FRONT CONTINUES TO PUSH
FURTHER TO OUR SOUTH. SATURDAY LOOKS DRY AS HIGH PRESSURE BRIEFLY
BUILDS BACK INTO THE MID ATLANTIC. SHOWERS MAY RETURN SUNDAY INTO
MONDAY AS YET ANOTHER WAVE OF LOW PRESSURE IS EXPECTED TO ORGANIZE
OVER THE GREAT PLAINS AND TRACK EASTWARD ALONG THE STATIONARY
FRONT.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
VFR THRU AT LEAST 18Z FOR THE TERMINALS. THE WIND ARE STILL RATHER
LIGHT SO FAR MORNING FROM PHL NORTHWARD. FARTHER SOUTH IN THE WARM
SECTOR, SW WINDS ARE GUSTING 20-25 KT. EXPECT WIND GUSTS OF
SIMILAR MAGNITUDE TO DEVELOP FARTHER NORTH LATE THIS MORNING AND
EARLY AFTERNOON.
THE AFTERNOON IS EXPECTED TO BEGIN WITH VFR CONDITIONS ALONG WITH
A CONTINUATION OF THE GUSTY WEST SOUTHWEST WIND. HOWEVER, A COLD
FRONT APPROACHING FROM THE NORTH SHOULD BRING SHOWERS AND
THUNDERSTORMS. THE THUNDERSTORMS WILL BE ACCOMPANIED BY BRIEFLY
MODERATE TO HEAVY RAINFALL, LOW CEILING AND VISIBILITY VALUES, AND
PERHAPS WIND GUSTS IN EXCESS OF 35 KNOTS.
THE FRONT IS ANTICIPATED TO PASS THROUGH KABE, KRDG AND KTTN
BETWEEN ABOUT 2200 AND 2300Z BRINGING AND END TO THE POTENTIAL FOR
SHOWERS AND THUNDERSTORMS. THE FRONT IS EXPECTED TO ARRIVE AT KPNE
AND KPHL AROUND 0000Z, AND AT KILG, KACY AND KMIV ABOUT 0100Z. THE
WIND IS FORECAST TO SHIFT TO THE NORTHWEST, THEN TO THE NORTH AND
NORTHEAST AND SPEEDS SHOULD DECREASE TO AROUND 8 TO 12 KNOTS.
OUTLOOK...
WEDNESDAY...MVFR CIGS POSSIBLE FOR THE SOUTHERN TWO-THIRDS OF THE
AREA, WITH VFR POSSIBLE NORTHERN AREAS.
WEDNESDAY NIGHT...VFR EXPECTED.
THURSDAY-THURSDAY NIGHT...VFR EARLY, BECOMING MVFR OR IFR LATE IN
THE DAY AND OVERNIGHT WITH RAIN POSSIBLE.
FRIDAY-FRIDAY NIGHT...MVFR CIGS POSSIBLE WITH SCATTERED SHOWERS.
SATURDAY...VFR CIGS, WITH PERIODS OF MVFR POSSIBLE.
&&
.MARINE...
THE SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR OUR OCEAN WATERS
FOR TODAY AND TONIGHT. THE ADVISORY IS MAINLY IN EFFECT FOR WAVE
HEIGHTS AROUND 5 FEET. HOWEVER, LOCALIZED GUSTS NEAR 25 KNOTS ARE
POSSIBLE. A SMALL CRAFT ADVISORY HAS BEEN ISSUED FOR DELAWARE BAY
AND IT IS IN EFFECT UNTIL 600 PM.
THE WIND DIRECTION IS FORECAST TO FAVOR THE SOUTHWEST FOR TODAY.
A COLD FRONT FROM THE NORTH WILL DROP THROUGH THE REGION THIS
EVENING AND THE WIND DIRECTION IS EXPECTED TO SHIFT TO THE
NORTHWEST TO NORTHEAST QUADRANT.
OUTLOOK...
WEDNESDAY-SATURDAY...SUB-SMALL CRAFT ADVISORY CONDITIONS EXPECTED
TO CONTINUE. WINDS COULD PERIODICALLY GUST AROUND 20 KNOTS,
ESPECIALLY THURSDAY AND THURSDAY NIGHT WHEN GUSTS COULD APPROACH
ADVISORY LEVELS.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ430-
431.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...KLEIN
SHORT TERM...IOVINO
LONG TERM...KLEIN/ROBERTSON
AVIATION...IOVINO/KLEIN/ROBERTSON
MARINE...IOVINO/ROBERTSON
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
1218 PM CDT TUE APR 26 2016
.SHORT TERM...
326 AM CDT
THROUGH WEDNESDAY...
WHEN IT COMES TO CHICAGO`S WEATHER...ESPECIALLY IN THE
SPRING...WHAT A DIFFERENCE A DAY CAN MAKE. OR...IF FOR AREAS
CLOSER TO THE LAKE...WHAT A DIFFERENCE A FEW MINUTES CAN MAKE. A
PNEUMONIA FRONT CAME BLASTING IN OFF THE LAKE A COUPLE HOURS AGO
WITH TEMP DROPS OF 20 DEGREES IN 15 MINUTES AND NOT TOO FAR FROM
30 DEGREES IN AN HOUR. LAKE ENHANCED FRONT WILL CONTINUE MOVING
ACROSS THE CWA THIS MORNING...THOUGH AS IT GETS FARTHER FROM THE
LAKE THE TEMP DROPS WILL BE LESS DRAMATIC AND THE FRONT SHOULD
HAVE A TENDENCY TO SLOW AS IT MOVES INTO CENTRAL IL THIS
AFTERNOON. LARGE BANK OF POST FRONTAL STRATUS BLANKETS MOST OF WI
AND POINTS NORTH. WHILE IT LAGS A BIT BEHIND THE SFC WIND SHIFT
BUT HAS BEEN STEADILY SEEPING SOUTHWARD AND ANTICIPATE IT TO
OVERSPREAD MOST OF THE CWA THIS MORNING. WHILE CIGS WILL LIKELY
INCH UPWARD TODAY...THINKING THAT STRATUS WILL PROBABLY HOLD
STRONG THROUGH THE DAY MOST AREAS...ESPECIALLY NORTH OF I-80 AND
NEAR THE LAKE. MOST OF THE NORTHERN 2/3RD OF THE CWA WILL PROBABLY
STRUGGLE TO GET OUT OF THE 50S TODAY AND AREAS NEAR THE LAKE WILL
LIKELY SPEND MOST OF THE DAY IN THE LOW TO MID 40S WITH LOW CLOUDS
AND A STIFF WIND OFF THE LAKE.
CLOUDY AND CHILLY CONDITIONS EXPECTED TO PERSIST THROUGH WEDNESDAY
WITH GRADUALLY INCREASING CHANCES FOR RAIN/SHOWERS AS THE DAY
WEARS ON WEDNESDAY AND POWERFUL SYSTEM AFFECTING THE CENTRAL AND
SOUTHERN PLAINS TODAY MOVES SLOWLY EAST TOWARD OUR AREA. A STEADY
FEED OF DRY AIR ADVECTING IN ON THE FAIRLY BRISK EASTERLY WINDS
WILL PROBABLY SLOW THE FORWARD PROGRESS OF RAIN ACROSS OUR
AREA...THOUGH STILL LOOKS LIKE MOST AREAS WILL SEE SHOWERS BY
WEDNESDAY AFTERNOON AND ESPECIALLY WEDNESDAY NIGHT. THE CYCLONE
WILL BE IN THE PROCESS OF BECOMING VERTICALLY STACKED AND
WEAKENING AS IT MOVES INTO THE AREA WEDNESDAY INTO WEDNESDAY NIGHT
WITH MAJORITY OF INSTABILITY PROGGED TO REMAIN SOUTH OF OUR
CWA...SO WHILE WE CANNOT TOTALLY RULE OUT A
THUNDERSTORM...ESPECIALLY SOUTH OF I-80...THE CHANCES OF THUNDER
LOOK PRETTY LOW.
IZZI
&&
.LONG TERM...
326 AM CDT
WEDNESDAY NIGHT THROUGH TUESDAY...
THE SAME SYSTEM WILL STILL BE IN THE AREA THURSDAY CONTINUING TO
WEAKEN AND FILL. ENOUGH COLD AIR ALOFT SHOULD BE PRESENT TO
SUPPORT A CONTINUED THREAT OF SHOWERS INTO THE DAY THURSDAY BEFORE
THIS SYSTEM FINALLY DISSIPATES AS IT MOVES EAST AWAY FROM THE AREA
THURSDAY NIGHT. A BREAK IN PRECIP CHANCES IS THEN EXPECTED FRIDAY
AND PROBABLY MOST IF NOT ALL OF SATURDAY AS WELL BEFORE THE NEXT
BIG SHORTWAVE/CLOSED EMERGES TO THE LEE OF THE ROCKIES AND HEADS
TOWARD THE MIDWEST BY LATER IN THE WEEKEND. HAVE TRIED TO SLOW
POPS A BIT FROM BLENDED MODEL GUIDANCE...BUT SUSPECT FURTHER
SLOWING IN THE ARRIVAL OF PRECIP COULD BE NEEDED AS MEDIUM RANGE
MODELS TEND TO SLOW THESE TYPE OF SYSTEMS EASTWARD PROGRESS AT
THIS DISTANCES. ONCE THE SYSTEM DOES EVENTUALLY ARRIVE LATER IN
THE WEEKEND LOOK FOR MORE RAIN AND PERHAPS SOME THUNDER CHANCES AS
WELL.
NOW THAT WINDS ARE SHIFTING TO NORTHEAST BEHIND THE FRONT MOVING
THROUGH THE AREA EARLY THIS MORNING...LOOK FOR THE NORTHEAST OR
EAST WIND REGIME TO REMAIN LOCKED IN THROUGH THE UPCOMING WEEKEND.
THE EASTERLY WINDS AND FREQUENT BOUTS OF CLOUD COVER AND RAIN WILL
KEEP TEMPS BELOW AVERAGE THROUGH THE UPCOMING WEEKEND. NO WHERE
WILL THAT BE THE CASE MORESO THAN NEAR THE LAKE WHERE TEMPERATURES
PROBABLY WONT REACH 50 DEGREES AGAIN THROUGH THE REST OF THE AND
POSSIBLY THROUGH THE WEEKEND AS WELL.
IZZI
&&
.AVIATION...
FOR THE 18Z TAFS...
CONCERNS CENTER AROUND MVFR CEILINGS AND SPECIFIC END
TIME...FOLLOWED BY CONTINUED EAST WINDS. FOCUS SHIFTS TO RAIN
POTENTIAL AND TIMING FOR WEDNESDAY AFTERNOON.
CEILINGS CONTINUE TO RISE PER MODEL GUIDANCE WITH MOST LOCATIONS
INTO THE MVFR CATEGORY AS OF 17Z...WITH THE EXCEPTION BEING RIGHT
AT THE LAKEFRONT WHERE IFR WILL LINGER A BIT LONGER. REMNANTS OF
THE MORNING CONVECTIVE COMPLEX WILL CONTINUE TO DRIFT
EAST/SOUTHEAST TODAY AND WILL NOT IMPACT THE TERMINALS DIRECTLY.
GUIDANCE CONTINUES TO SUGGEST MVFR STRATUS WILL LINGER FOR MOST OF
THE DAY AND AT LEAST THE EARLY EVENING HOURS. GUIDANCE IS MIXED AS
TO WHETHER THE MVFR CIGS WILL LAST INTO THE MORNING
HOURS...POSSIBLY LIFTING TO VFR OVERNIGHT THEN RETURNING TO MVFR
IN THE MORNING FOR A TIME. DEWPOINTS DO NOT DROP MUCH
TONIGHT...BUT COOLING OVERNIGHT WILL BE LIMITED DUE TO CONTINUED
EAST WINDS. THESE FACTORS SUGGEST STATUS QUO OF AT LEAST SOME
SCATTERED LOW VFR/HIGH MVFR CLOUDS BEING AROUND.
THE LARGE STORM SYSTEM TO OUR WEST WILL SLOWLY DRIFT EASTWARD ON
WEDNESDAY. HIGHER CONFIDENCE EXISTS IN SHOWERS/EMBEDDED
THUNDERSTORM CHANCES DURING THE EVENING HOURS...BUT AN ELEVATED
WARM FRONT WILL BEGIN MOVING NORTHWARD DURING THE AFTERNOON. AT
THIS POINT THUNDER CHANCES IN THE AFTERNOON APPEAR TOO LOW TO
INCLUDE IN THE TAF. SOME GUIDANCE EVEN HOLDS OF ON THE SHOWER
ACTIVITY UNTIL LATE IN THE DAY. WILL HANDLE THIS WITH A
COMPROMISE TIMING AROUND 20-21Z IN THE 30 HR ORD TAF.
KMD
&&
.MARINE...
317 AM CDT
HEADLINES...GUSTS ARE BELOW GALE FORCE OVER THE NORTHERN END OF THE
LAKE SO CANCELLED THE GALE WARNING EARLY. LEFT THE SMALL CRAFT
ADVISORIES AS IS. THE LATEST WAVE MODEL SUGGESTS THE SCY FOR THE IL
WATERS NEEDS TO BE EXTENDED. ALSO CONSIDERED EXTENDING THE SCY FOR
POINTS BETWEEN CALUMET HARBOR AND GARY. DO NOT HAVE ENOUGH
CONFIDENCE TO EXTEND EITHER OF THOSE SCY/S JUST YET.
THE LOW IS OVER SOUTHWEST MICHIGAN AND IT WILL CONTINUE EAST. ITS
COLD FRONT IS NOW SOUTH OF THE LAKE WITH WINDS NORTH TO NORTHEAST
ACROSS THE LAKE. WINDS WILL VARY BETWEEN NORTH AND EAST THROUGH
EARLY NEXT WEEK. THE NEXT LOW FORMS OVER THE PLAINS THIS AFTERNOON
AND PASSES OVER CENTRAL IL THURSDAY. THE SOUTHERN EDGE OF HIGH
PRESSURE CENTERED OVER HUDSON BAY SWINGS THROUGH FRIDAY WITH ANOTHER
LOW FORMING OVER THE PLAINS SATURDAY. GUIDANCE DIFFERS ON THE PATH
OF THE LOW...BUT THE MAIN MODELS BRING IT INTO NORTHERN IL EARLY
NEXT WEEK.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 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:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1047 AM CDT TUE APR 26 2016
.SHORT TERM...(Today)
ISSUED AT 335 AM CDT Tue Apr 26 2016
Weak cold currently stretching from northwest Indiana southwest
through our far northern counties into northeast Missouri will slide
south across the forecast area today. Convection has had a hard time
developing along the boundary overnight due to weak convergence and
stronger lift further north with the surface low. Short term models
suggest other than some isolated showers along the southward moving
boundary, the better threat for showers and thunderstorms will be
associated with shortwave energy now pushing through central Kansas.
Convection has already started just ahead of that feature well to
our west with the stronger convection progged to shift east and
affect our southeast counties this afternoon.
Looks like a fairly sharp cutoff to the precip along and north of
Interstate 74 where the lower POPs will be today, while areas south
of I-72 will have the higher rain threat this afternoon. Surface
based capes of around 2500 J/Kg were noted south of I-72 this
afternoon, although 0-6km shear values were not much higher than 25
kts during this same time period. Hail and gusty winds will be
possible over southeast Illinois with this cluster of storms this
afternoon. With the frontal boundary shifting into southeast
Illinois later today, will have a rather large temperature gradient
this afternoon with forecast highs ranging from around 70 over our
far northern counties, to the lower 80s over extreme southeast
Illinois.
.LONG TERM...(Tonight through Monday)
ISSUED AT 335 AM CDT Tue Apr 26 2016
Forecast really is not changing much in this round, with the
exception of maybe building a bit of a break into the evening hours
without precip. However, the deep low spinning out over the Plains
and developing storm system will slowly spread rain/thunder into the
region after midnight especially...along a developing warm frontal
feature. The surface low remains out to the west for Wednesday and
is slow to progress with the deep low over eastern Canada/NE CONUS.
Much of Central Illinois remains in the warm sector with a potential
for some persistent and good rain Wed-Wed night along...up to an
inch or so. Low slow to move out Thursday as the rain comes to an
end briefly with a break before the next wave ejects out of the SW
across the Midwest for the weekend.
Rain chances return for Friday night through the weekend with a
similar setup happening again. Some variability in the
tracks/strength of the sfc system. The ECMWF is initially more well
developed with a classic low...but both the European and the GFS get
a messier look by the end of the weekend, with the system shearing
out over the Ohio River Valley and slowing any progression. Either
way, next weekend looks wetter than not.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1045 AM CDT Tue Apr 26 2016
Updated the forecast to increase chances of showers and
thunderstorms south of I-72 this afternoon and also increase cloud
cover across CWA. MCS over southern IA and northern MO is
spreading clouds eastward toward I-57 late this morning, while
leading edge of showers and thunderstorms moving into west central
IL just west of CWA. HRRR model seems 1-2 hours too slow with this
convection spreading ESE across areas south of I-74 this
afternoon and following the quicker SPC high res model solution.
SPC has slight risk of severe storms over much of Clay and sw
Jasper counties by late afternoon. Frontal boundary is pressing
southward toward I-72 late this morning and will push south of
I-70 late this afternoon. Temps currently range from mid 60s from
Macomb to Lacon north to the mid 70s from I-72 south. Highs today
to range from the upper 60s to near 70F from Galesburg and Lacon
north to the upper 70s and lower 80s from I-72 south.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Smith
LONG TERM...HJS
AVIATION...07
AREA FORECAST DISCUSSION...UPDATED
NWS QUAD CITIES IA IL
1257 PM CDT TUE APR 26 2016
...18Z AVIATION UPDATE...
.UPDATE...
ISSUED AT 1120 AM CDT TUE APR 26 2016
UPDATE TO THE FORECAST DUE TO THE CONVECTION THAT IS BUBBLING
ACROSS THE AREA. CONVERGENCE AT THE H8 LEVEL THIS MORNING WAS
AIDING IN THE DEVELOPMENT OF ELEVATED CONVECTION ACROSS THE CWA.
HIRES GUIDANCE FAVORS THE CONVECTION DIVING SOUTH ACROSS THE
CONVERGENCE ZONE. PROB SEVERE AND MRMS DATA HAVE SUGGESTED THAT
THESE CELLS COULD HAVE SOME SMALL HAIL....HOWEVER NOTHING HAS BEEN
REPORTED YET. AS SUCH HAVE UPDATED POPS/WX ACROSS THE AREA. ALSO
HAVE UPDATED THE SKY TO 100%.
UPDATE ISSUED AT 702 AM CDT TUE APR 26 2016
THE GROWING MISSOURI MCS HAS PRODUCED FORCING FOR SHOWERS ALL THE
WAY UP TO JUST SOUTH OF INTERSTATE 80 IN CENTRAL IOWA. THIS IS
ONLY BEING HANDLED BY THE HRRR AND PARTIALLY THE 06Z NAM. I HAVE
UPDATED THE SLIGHT CHANCE POPS IN THE SOUTH AND EXPANDED AND UPPED
THEM TO INCLUDE SOME EMBEDDED THUNDER THIS MORNING.
ERVIN
&&
.SYNOPSIS...
ISSUED AT 307 AM CDT TUE APR 26 2016
A COLD FRONT HAS NOW PUSHED INTO OUR FAR SOUTHERN COUNTIES...WITH
ANOTHER PUSH OF SIGNIFICANTLY COLDER AIR ARRIVING TOWARD SUNRISE
THIS MORNING...AS LAKE MICHIGAN AFFECTED AIR PUSHES SOUTHWEST OVER
OUR NORTHERN COUNTIES. THIS WILL CREATE A STRONG TEMPERATURE
CONTRAST OVER THE CWA TODAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CDT TUE APR 26 2016
BY 7 AM...THE NORTHEAST WINDS AND STRATUS ASSOCIATED WITH THE LAKE
MICHIGAN AFFECTED COLD WILL SPREAD INTO THE NORTHEAST
COUNTIES...POSSIBLY AS FAR SOUTH TO REACH HIGHWAY 30. BY MID
MORNING...THE STRATUS SHOULD REACH DOWN TO CEDAR RAPIDS AND THE QUAD
CITIES. HOWEVER...FARTHER SOUTH...BY MID MORNING...THE STRONG
SUNSHINE MIXED WITH MID CLOUDS AND HIGH CLOUDS SHOULD ALLOW FOR
HEATING THAT MAY HALT THE STRATUS FROM GOING MUCH FARTHER SOUTH
DURING THE DAY. THIS CREATES A DAY WHERE THE SOUTH SHOULD WARM UP TO
THE MID TO UPPER 70S...WHILE THE NORTH STRUGGLES THROUGH TO HIGHS
ONLY IN THE UPPER 50S...AND DEPENDING ON WHERE THE STRATUS CAN STAY
OPAQUE THROUGH THE DAY...THAT MAY BE OPTIMISTIC.
DESPITE THE CHALLENGING TEMPERATURES TODAY...IS SHOULD BE DRY DAY
FOR NEARLY OFF THE CWA...AS ONLY THE FAR SOUTH COULD SEE SOME LIGHT
RAIN SHOWERS FROM THE NORTHERN EDGE OF THE MISSOURI ACTIVITY...WHICH
SHOWS A MORE LIKELY CHANCE TO DROP SOUTHEAST...MISSING OUR CWA ALL
TOGETHER. THE NEXT CHANCE FOR RAIN WILL ARRIVE TONIGHT...MAINLY IN
THE SOUTHWEST COUNTIES. LOOKING SYNOPTICALLY...DESPITE THE WARM
FRONT NEAR NORTHERN MISSOURI...THERE WILL BE RIDGING ALOFT UNTIL
LATE TONIGHT. THAT SHOULD KEEP THE FOCUS FOR WAA DRIVEN SHOWERS AND
THUNDERSTORMS WEST OF EASTERN IOWA FOR QUITE A WHILE BEFORE A MORE
WIDESPREAD RAIN ARRIVES LATE TONIGHT. THE LOW LEVEL CAA WILL
CONTINUE AS STRENGTHENING NORTHEAST WINDS USHER IN LOW DEWPOINTS.
THUS...ANY RAIN WILL RAPIDLY COOL OFF TEMPERATURES EVEN FURTHER
THROUGH WETBULB AFFECTS. THIS WILL CREATE A COLD MARCH LIKE
NIGHT...WITH RAIN ARRIVING IN MOST AREAS AFTER MIDNIGHT...AND ONLY
EMBEDDED RUMBLES OF THUNDER EXPECTED AS CONVECTION ARRIVING FROM
FARTHER SOUTHWEST STRATIFIES INTO A LIGHT TO MODERATE RAIN SHIELD.
THE LATE ARRIVAL OF RAIN TONIGHT...RESULTS IN A NEARLY DRY FORECAST
FOR THE NEXT 24 HOURS IN OUR NORTHEASTERN COUNTIES EAST OF DUBUQUE.
ERVIN
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 307 AM CDT TUE APR 26 2016
FORECAST FOCUS ON TWO STRONG STORM SYSTEMS BRINGING WIDESPREAD RAIN
AND EMBEDDED THUNDERSTORMS. TEMPERATURES WILL BE BELOW NORMAL
DURING MUCH OF THE EXTENDED PERIOD.
WEDNESDAY THROUGH THURSDAY...MODELS HAVE BEEN FAIRLY CONSISTENT WITH
SHOWING LOW PRESSURE LIFTING OUT OF THE CENTRAL PLAINS AND INTO IOWA
AS A NEGATIVE-TILT TROUGH. STRONG FORCING WILL ACCOMPANY THIS SYSTEM
WITH A NICE WARM MOIST CONVEYOR BELT FROM THE SOUTH LIFTING OVER THE
COOL AIRMASS IN THE CWA...DUE TO A NORTHEAST TO EAST WIND COMING OFF
THE GREAT LAKES. A FRONTAL BOUNDARY WILL BE NEARLY STALLED IN FAR
NORTHERN MO. WIDESPREAD MODERATE RAIN AND EMBEDDED THUNDERSTORMS
WILL BE THE RULE WITH QPF AMOUNTS AT LEAST IN THE 1/2 TO 1 INCH
RANGE...POSSIBLY SOME HIGHER AMOUNTS WITH PWAT`S OVER 1.30 INCHES.
THERE IS THE POTENTIAL FOR A FEW STRONGER STORMS IN OUR FAR SOUTHERN
CWA CLOSER TO THE BOUNDARY AND SURFACE LOW. HOWEVER...THE MAIN
SEVERE WEATHER EVENT SHOULD REMAIN FARTHER SOUTH IN MO AND INTO THE
LOWER MS VALLEY. THE SYSTEM WILL BE OCCLUDING LATER WEDNESDAY NIGHT
CUTTING OFF THE DEEPER MOISTURE SOURCE WITH THE RAIN BECOMING
SCATTERED AND LIGHT. THE OCCLUDED LOW AND ASSOCIATED COLD POOL WILL
DRIFT ACROSS THE DVN CWA ON THURSDAY SO WILL KEEP THE MENTION OF
SCATTERED RAIN SHOWERS. TEMPERATURES ON WEDNESDAY WILL RANGE FROM
THE LOWER TO MID 50S NORTH TO THE MID TO UPPER 60S SOUTH. THIS WILL
FEEL LIKE A RAW DAY IN OUR NORTHERN COUNTIES WITH RAIN...COOL
TEMPERATURES AND AN EAST WIND GUSTING TO 30 MPH. HIGHS ON THURSDAY
WILL RANGE FROM THE LOWER 50S NORTH TO THE MID 60S FAR SOUTH.
THURSDAY NIGHT THROUGH FRIDAY...TIME TO BRIEFLY DRY OUT AS WEAK HIGH
PRESSURE RIDGE BUILDS INTO THE AREA FROM THE NORTH. HIGHS ON FRIDAY
WILL BE A TAD WARMER AS ANOTHER STRONG STORM SYSTEM BEGINS TO TAKE
SHAPE IN THE CENTRAL PLAINS.
FRIDAY NIGHT THROUGH SUNDAY...ANOTHER STRONG STORM SYSTEM WILL TRACK
OUT OF THE CENTRAL PLAINS AND THEN SLOWLY INTO THE CORN BELT. THIS
LOOKS TO BE A SIMILAR SET UP AS THE MID WEEK EVENT IF NOT A BIT
FARTHER NORTH. SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS CAN BE
EXPECTED DURING THE WEEKEND WITH WIDESPREAD QPF AMOUNTS ONCE AGAIN
AT LEAST 1/2 TO 1 INCH. IF THE ECWMF IS CORRECT THERE IS THE
POTENTIAL FOR STRONG STORMS ON SUNDAY ESPECIALLY IN WESTERN IL AS
THE SURFACE LOW TRACKS NEAR THAT AREA. HOWEVER...THE GFS TAKES THE
LOW FARTHER TO THE SOUTH WHICH WOULD REDUCE THIS POTENTIAL.
TEMPERATURES OVER THE WEEKEND WILL ONCE AGAIN BE BELOW NORMAL WITH
HIGHS IN THE 50S NORTH TO 60S SOUTH.
HAASE
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1247 PM CDT TUE APR 26 2016
DIFFICULT AVIATION FORECAST THROUGH THE PERIOD AS THUNDERSTORMS
AND LOW CLOUDS ARE AFFECTING THE TAF SITES IN THE SHORT TERM AND
THEN ANOTHER ROUND OF THUNDER AND LOW CIGS IN THE AM TOMORROW.
LOOKS LIKE THE IFR AND NOW MVFR DECK THAT MOVED IN FROM THE NORTH
STOPPED A FEW MILES FROM MLI. CONVECTION SHOULD KEEP AREAS SOUTH
IN VFR FLIGHT RULES. LATER TODAY WINDS SHOULD INCREASE AND MVFR
CIGS SHOULD REDEVELOP AS A WARM FRONT TRIES TO MOVE NORTH EARLY
TOMORROW. ALL SITES WITH THE EXCEPTION OF DBQ HAVE A CHANCE FOR
THUNDER...HOWEVER AT THIS TIME WITH LOW CONFIDENCE ON TIMING HAVE
GONE WITH PROB30 AT THOSE SITES.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...GIBBS
SYNOPSIS...ERVIN
SHORT TERM...ERVIN
LONG TERM...HAASE
AVIATION...GIBBS
AREA FORECAST DISCUSSION...UPDATED
NWS QUAD CITIES IA IL
1120 AM CDT TUE APR 26 2016
.UPDATE...
ISSUED AT 1120 AM CDT TUE APR 26 2016
UPDATE TO THE FORECAST DUE TO THE CONVECTION THAT IS BUBBLING
ACROSS THE AREA. CONVERGENCE AT THE H8 LEVEL THIS MORNING WAS
AIDING IN THE DEVELOPMENT OF ELEVATED CONVECTION ACROSS THE CWA.
HIRES GUIDANCE FAVORS THE CONVECTION DIVING SOUTH ACROSS THE
CONVERGENCE ZONE. PROB SEVERE AND MRMS DATA HAVE SUGGESTED THAT
THESE CELLS COULD HAVE SOME SMALL HAIL....HOWEVER NOTHING HAS BEEN
REPORTED YET. AS SUCH HAVE UPDATED POPS/WX ACROSS THE AREA. ALSO
HAVE UPDATED THE SKY TO 100%.
UPDATE ISSUED AT 702 AM CDT TUE APR 26 2016
THE GROWING MISSOURI MCS HAS PRODUCED FORCING FOR SHOWERS ALL THE
WAY UP TO JUST SOUTH OF INTERSTATE 80 IN CENTRAL IOWA. THIS IS
ONLY BEING HANDLED BY THE HRRR AND PARTIALLY THE 06Z NAM. I HAVE
UPDATED THE SLIGHT CHANCE POPS IN THE SOUTH AND EXPANDED AND UPPED
THEM TO INCLUDE SOME EMBEDDED THUNDER THIS MORNING.
ERVIN
&&
.SYNOPSIS...
ISSUED AT 307 AM CDT TUE APR 26 2016
A COLD FRONT HAS NOW PUSHED INTO OUR FAR SOUTHERN COUNTIES...WITH
ANOTHER PUSH OF SIGNIFICANTLY COLDER AIR ARRIVING TOWARD SUNRISE
THIS MORNING...AS LAKE MICHIGAN AFFECTED AIR PUSHES SOUTHWEST OVER
OUR NORTHERN COUNTIES. THIS WILL CREATE A STRONG TEMPERATURE
CONTRAST OVER THE CWA TODAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM CDT TUE APR 26 2016
BY 7 AM...THE NORTHEAST WINDS AND STRATUS ASSOCIATED WITH THE LAKE
MICHIGAN AFFECTED COLD WILL SPREAD INTO THE NORTHEAST
COUNTIES...POSSIBLY AS FAR SOUTH TO REACH HIGHWAY 30. BY MID
MORNING...THE STRATUS SHOULD REACH DOWN TO CEDAR RAPIDS AND THE QUAD
CITIES. HOWEVER...FARTHER SOUTH...BY MID MORNING...THE STRONG
SUNSHINE MIXED WITH MID CLOUDS AND HIGH CLOUDS SHOULD ALLOW FOR
HEATING THAT MAY HALT THE STRATUS FROM GOING MUCH FARTHER SOUTH
DURING THE DAY. THIS CREATES A DAY WHERE THE SOUTH SHOULD WARM UP TO
THE MID TO UPPER 70S...WHILE THE NORTH STRUGGLES THROUGH TO HIGHS
ONLY IN THE UPPER 50S...AND DEPENDING ON WHERE THE STRATUS CAN STAY
OPAQUE THROUGH THE DAY...THAT MAY BE OPTIMISTIC.
DESPITE THE CHALLENGING TEMPERATURES TODAY...IS SHOULD BE DRY DAY
FOR NEARLY OFF THE CWA...AS ONLY THE FAR SOUTH COULD SEE SOME LIGHT
RAIN SHOWERS FROM THE NORTHERN EDGE OF THE MISSOURI ACTIVITY...WHICH
SHOWS A MORE LIKELY CHANCE TO DROP SOUTHEAST...MISSING OUR CWA ALL
TOGETHER. THE NEXT CHANCE FOR RAIN WILL ARRIVE TONIGHT...MAINLY IN
THE SOUTHWEST COUNTIES. LOOKING SYNOPTICALLY...DESPITE THE WARM
FRONT NEAR NORTHERN MISSOURI...THERE WILL BE RIDGING ALOFT UNTIL
LATE TONIGHT. THAT SHOULD KEEP THE FOCUS FOR WAA DRIVEN SHOWERS AND
THUNDERSTORMS WEST OF EASTERN IOWA FOR QUITE A WHILE BEFORE A MORE
WIDESPREAD RAIN ARRIVES LATE TONIGHT. THE LOW LEVEL CAA WILL
CONTINUE AS STRENGTHENING NORTHEAST WINDS USHER IN LOW DEWPOINTS.
THUS...ANY RAIN WILL RAPIDLY COOL OFF TEMPERATURES EVEN FURTHER
THROUGH WETBULB AFFECTS. THIS WILL CREATE A COLD MARCH LIKE
NIGHT...WITH RAIN ARRIVING IN MOST AREAS AFTER MIDNIGHT...AND ONLY
EMBEDDED RUMBLES OF THUNDER EXPECTED AS CONVECTION ARRIVING FROM
FARTHER SOUTHWEST STRATIFIES INTO A LIGHT TO MODERATE RAIN SHIELD.
THE LATE ARRIVAL OF RAIN TONIGHT...RESULTS IN A NEARLY DRY FORECAST
FOR THE NEXT 24 HOURS IN OUR NORTHEASTERN COUNTIES EAST OF DUBUQUE.
ERVIN
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 307 AM CDT TUE APR 26 2016
FORECAST FOCUS ON TWO STRONG STORM SYSTEMS BRINGING WIDESPREAD RAIN
AND EMBEDDED THUNDERSTORMS. TEMPERATURES WILL BE BELOW NORMAL
DURING MUCH OF THE EXTENDED PERIOD.
WEDNESDAY THROUGH THURSDAY...MODELS HAVE BEEN FAIRLY CONSISTENT WITH
SHOWING LOW PRESSURE LIFTING OUT OF THE CENTRAL PLAINS AND INTO IOWA
AS A NEGATIVE-TILT TROUGH. STRONG FORCING WILL ACCOMPANY THIS SYSTEM
WITH A NICE WARM MOIST CONVEYOR BELT FROM THE SOUTH LIFTING OVER THE
COOL AIRMASS IN THE CWA...DUE TO A NORTHEAST TO EAST WIND COMING OFF
THE GREAT LAKES. A FRONTAL BOUNDARY WILL BE NEARLY STALLED IN FAR
NORTHERN MO. WIDESPREAD MODERATE RAIN AND EMBEDDED THUNDERSTORMS
WILL BE THE RULE WITH QPF AMOUNTS AT LEAST IN THE 1/2 TO 1 INCH
RANGE...POSSIBLY SOME HIGHER AMOUNTS WITH PWAT`S OVER 1.30 INCHES.
THERE IS THE POTENTIAL FOR A FEW STRONGER STORMS IN OUR FAR SOUTHERN
CWA CLOSER TO THE BOUNDARY AND SURFACE LOW. HOWEVER...THE MAIN
SEVERE WEATHER EVENT SHOULD REMAIN FARTHER SOUTH IN MO AND INTO THE
LOWER MS VALLEY. THE SYSTEM WILL BE OCCLUDING LATER WEDNESDAY NIGHT
CUTTING OFF THE DEEPER MOISTURE SOURCE WITH THE RAIN BECOMING
SCATTERED AND LIGHT. THE OCCLUDED LOW AND ASSOCIATED COLD POOL WILL
DRIFT ACROSS THE DVN CWA ON THURSDAY SO WILL KEEP THE MENTION OF
SCATTERED RAIN SHOWERS. TEMPERATURES ON WEDNESDAY WILL RANGE FROM
THE LOWER TO MID 50S NORTH TO THE MID TO UPPER 60S SOUTH. THIS WILL
FEEL LIKE A RAW DAY IN OUR NORTHERN COUNTIES WITH RAIN...COOL
TEMPERATURES AND AN EAST WIND GUSTING TO 30 MPH. HIGHS ON THURSDAY
WILL RANGE FROM THE LOWER 50S NORTH TO THE MID 60S FAR SOUTH.
THURSDAY NIGHT THROUGH FRIDAY...TIME TO BRIEFLY DRY OUT AS WEAK HIGH
PRESSURE RIDGE BUILDS INTO THE AREA FROM THE NORTH. HIGHS ON FRIDAY
WILL BE A TAD WARMER AS ANOTHER STRONG STORM SYSTEM BEGINS TO TAKE
SHAPE IN THE CENTRAL PLAINS.
FRIDAY NIGHT THROUGH SUNDAY...ANOTHER STRONG STORM SYSTEM WILL TRACK
OUT OF THE CENTRAL PLAINS AND THEN SLOWLY INTO THE CORN BELT. THIS
LOOKS TO BE A SIMILAR SET UP AS THE MID WEEK EVENT IF NOT A BIT
FARTHER NORTH. SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS CAN BE
EXPECTED DURING THE WEEKEND WITH WIDESPREAD QPF AMOUNTS ONCE AGAIN
AT LEAST 1/2 TO 1 INCH. IF THE ECWMF IS CORRECT THERE IS THE
POTENTIAL FOR STRONG STORMS ON SUNDAY ESPECIALLY IN WESTERN IL AS
THE SURFACE LOW TRACKS NEAR THAT AREA. HOWEVER...THE GFS TAKES THE
LOW FARTHER TO THE SOUTH WHICH WOULD REDUCE THIS POTENTIAL.
TEMPERATURES OVER THE WEEKEND WILL ONCE AGAIN BE BELOW NORMAL WITH
HIGHS IN THE 50S NORTH TO 60S SOUTH.
HAASE
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 610 AM CDT TUE APR 26 2016
A CHALLENGING AVIATION DAY AND NIGHT ARE IN STORE THROUGH
WEDNESDAY MORNING...AS LOW STRATUS AROUND 800 TO 1500 FT SPREAD
SOUTHWEST OUT OF WISCONSIN THIS MORNING...LIKELY REACHING BOTH CID
AND MLI BEFORE STALLING OUT NORTH OF BRL. A WARM FRONT WILL
DEVELOP OVER NORTHERN MISSOURI TODAY...TURNING ALL WINDS IN
EASTERN IOWA AND NORTHWEST ILLINOIS TO THE NORTHEAST AT 15 TO 25
KTS. AFTER SOME IMPROVEMENT TO VFR DURING THE AFTERNOON AND
EVENING HOURS...ANOTHER LAKE ENHANCED STRATUS DECK SHOULD MOVE
OVER THE ENTIRE AREA TONIGHT...LASTING THROUGH WEDNESDAY. RAIN
WILL ALSO SPREAD IN FROM MISSOURI LATE TONIGHT.
ERVIN
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...GIBBS
SYNOPSIS...ERVIN
SHORT TERM...ERVIN
LONG TERM...HAASE
AVIATION...ERVIN
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
348 PM CDT TUE APR 26 2016
.DISCUSSION...
MID-AFTERNOON SFC ANALYSIS SHOWS HIGH PRESSURE CENTERED OFF THE
CAROLINAS WHILE LOW PRESSURE IS NOTED OVER THE SRN PLAINS...
MAINTAINING AN ONSHORE LOW-LEVEL FLOW ACROSS THE FORECAST AREA.
WATER VAPOR IMAGERY SHOWS A MID/UPPER-LEVEL LOW SPINNING SLOWLY
NWD OVER THE LEE SIDE OF THE ROCKIES...WHILE WEAK RIDGING LINGERS
CLOSER TO HOME. AS DISCUSSED EARLIER JUST A FEW SHOWERS ARE
SHOWING UP ON RADAR OVER THE LOWER ATCHAFALAYA BASIN WHERE A
LITTLE BETTER MOISTURE IS FOUND...OTHERWISE WARM AND PARTLY
CLOUDY CONDITIONS PREVAIL PER LATEST SFC OBS.
SIMILAR TO YESTERDAY WITH THE ONGOING CONVECTION BEING OF A
DIURNAL NATURE...EXPECT IT TO DISSIPATE WITH SUNSET THIS EVENING.
THE FUN STARTS LATER TONIGHT AS THE WRN CONUS LOW ALOFT IS
PROGGED TO CONTINUE DRIFTING NWD WHILE A SIGNIFICANT SHORTWAVE
DROPS THROUGH IT ACROSS THE SRN PLAINS. COMBO OF INCREASING LIFT
ALOFT...EXCELLENT MOISTURE (FORECAST SOUNDINGS SHOW WELL IN EXCESS
OF 1.5 INCH PWATS) AND A STRENGTHENING LOW-LEVEL JET WILL LEAD TO
AT MINIMUM SCATTERED SHOWERS AND STORMS DEVELOPING LATER TONIGHT
ACROSS THE NWRN PORTIONS OF THE FORECAST AREA. LAST FEW HRRR RUNS
HAVE BEEN INDICATING SOME SORT OF MCS DEVELOPMENT WITH A SIMILAR
TIMEFRAME. THIS ACTIVITY WILL CONTINUE EWD ACROSS THE REGION
THROUGH THE DAY TOMORROW...WITH HIGHEST POPS ACROSS THE NRN 1/2 OF
THE AREA WHERE BETTER MOISTURE/LIFT ARE PROGGED. PRETTY MUCH THE
ENTIRE AREA HAS BEEN INCLUDED IN A SLIGHT RISK FOR LATER
TONIGHT/TOMORROW DUE TO THE AFOREMENTIONED FEATURES AS WELL AS
STEEP LAPSE RATES...FORECAST SOUNDINGS INDICATE GOOD INSTABILITY
IN PLACE BUT GIVEN A FAIRLY THICK CLOUD COVER WHICH SHOULD INHIBIT
INSOLATION AM A BIT CONCERNED WITH HOW UNSTABLE WE WILL BE SO NO
SEVERE WORDING HAS BEEN INCLUDED IN THE GRIDS/ZONES FOR NOW.
RAIN CHANCES WILL IMPROVE STARTING LATE TUESDAY NIGHT AS BEST
DIVERGENCE ALOFT BEGINS APPROACHING THE FORECAST AREA. COMBO WITH
INCREASING MOISTURE ALOFT WILL ALLOW FOR MORE SCATTERED TO
NUMEROUS SHOWERS AND STORMS BY WEDNESDAY. ENTIRE AREA IS
HIGHLIGHTED IN MARGINAL/SLIGHT RISK BY SPC FOR WEDNESDAY AS
FORECAST SOUNDINGS INDICATE INSTABILITY/CAPE/LAPSE RATES ALL
IMPROVING. BULK OF THE CONVECTION SHOULD MOVE OUT OF THE AREA
WEDNESDAY NIGHT.
SMALL POPS LINGER THROUGH THE REMAINDER OF THE WORK WEEK BEFORE
NEXT ROUND OF ENHANCED SHOWER/STORM ACTIVITY MOVES IN OVER THE
WEEKEND WITH THE ARRIVAL OF THE NEXT SIGNIFICANT DISTURBANCE
ALOFT.
&&
.MARINE...
HAVE INSERTED CAUTION HEADLINES ON THE OUTER WATERS AS THE COMBO
OF A TIGHTER GRADIENT AND LOW-LEVEL JETTING ELEVATE WINDS ON THE
COASTAL WATERS STARTING TONIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 70 83 69 86 / 10 70 40 20
LCH 73 81 72 84 / 20 60 30 20
LFT 73 84 74 85 / 10 50 40 30
BPT 73 83 72 85 / 30 60 20 20
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...SMALL CRAFT EXERCISE CAUTION FROM 7 PM CDT THIS EVENING THROUGH
WEDNESDAY MORNING FOR GMZ470-472-475.
&&
$$
25
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
230 PM EDT TUE APR 26 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 401 AM EDT TUE APR 26 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW SHRTWV MOVING THRU
THE UPR GREAT LKS EARLY THIS MRNG. BUT SINCE THIS DISTURBANCE IS
ENTERING CONFLUENT ZN BTWN NW FLOW OVER ONTARIO ARND CLOSED UPR LO
OVER THE CNDN MARITIMES AND WLY SRN BRANCH FLOW OVER THE CONUS...
THIS DISTURBANCE IS WEAKENING AS HINTED BY WARMING CLD TOP TEMPS
OVER THE CWA. MOST OF THE LINGERING PCPN IN THE FORM OF RA/SN IS OVER
THE E HALF CLOSER TO THE EXITING/WEAKENING DISTURBANCE...BUT
LINGERING LLVL MSTR UNDER THE MID LVL DRYING/SUBSIDENCE IN ITS WAKE
IS ALLOWING SOME LIGHT DRIZZLE/FLURRIES TO LINGER FARTHER W...
ESPECIALLY WHERE LLVL GUSTY NE FLOW IS UPSLOPING. BUT MUCH DRIER LLVL
AIR IS JUST TO THE N ASSOCIATED WITH HI PRES BLDG INTO NRN ONTARIO.
THE 00Z YPL RAOB IS QUITE DRY IN THE LLVLS...WITH H925/H85 DEWPT
DEPRESSIONS 17C/11C. STLT IMAGERY SHOWS THE NRN EDGE OF THE CLDS ARE
MOVING STEADILY TO THE S ACRS LK SUP WITH THIS DRY ADVECTION IN THE
LLVL NE FLOW. THIS CLRG LINE IS APRCHG THE KEWEENAW AT FCST ISSUANCE.
LOOKING TO THE W...THERE IS ANOTHER WEAKER SRN BRANCH SHRTWV SLIDING
E THRU CENTRAL MN.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON LLVL DRYING TRENDS/
IMPACT ON LINGERING LGT PCPN THIS MRNG AND THEN MIN TEMPS TNGT AS
DRIER/CHILLY AIRMASS ASSOCIATED WITH ONTARIO HI PRES WL DOMINATE.
TODAY...ALTHOUGH THERE ARE SOME DIFFERENCES ON THE TIMING...SHORTER
TERM MODELS ALL SHOW STEADY LLVL DRYING TODAY IN CONTINUED STEADY/
SLOWLY WEAKENING NE FLOW ON THE SRN FLANK OF ONTARIO HI PRES. GIVEN
THE STLT CLD TRENDS/FALLING SFC DEWPTS JUST TO THE N...PREFER THE
MODELS THAT SHOW MORE AGGRESSIVE LLVL DRYING. SO EXPECT LINGERING
DRIZZLE/FREEZING DRIZZLE/FLURRIES TO DIMINISH AND END BY ABOUT
12Z...LAST IN THE UPSLOPE HIER TERRAIN AREAS OF THE NCNTRL. SOME LO
CLDS MAY LINGER A BIT LONGER...BUT EVEN THESE SHOULD DISSOLVE N-S BY
LATE MRNG. ALTHOUGH SHRTWV IN MN IS FCST TO SLIDE E AND BRING SOME
DPVA/DEEP LYR QVECTOR CNVGC MAINLY TO THE WI BORDER AREAS...INFLUX OF
LLVL DRY AIR WL PREVENT ANY PCPN AND LIMIT IMPACT TO JUST MORE MID/HI
CLDS. DESPITE THE RETURN OF SOME SUNSHINE ESPECIALLY OVER THE NRN
TIER...NE FLOW OFF THE CHILLY LK SUP WATERS WL LIMIT DIURNAL TEMP
RECOVERY TO NO HIER THAN ABOUT 40 NEAR THE LK. TEMPS WL TOP OUT ARND
50 OVER THE SCENTRAL.
TNGT...ANY LINGERING CLDS ASSOCIATED WITH THE SECOND SHRTWV WL CLR
THE FAR SCENTRAL BY 00Z THIS EVNG...SETTING THE STAGE FOR A CHILLY
NGT AS THE SFC HI PRES IN ONTARIO EXTENDS A SFC RDG AXIS INTO THE
UPR LKS UNDER LARGE SCALE SUBSIDENCE. THE ONLY LIMITING FACTOR WL BE
A PERSISTENT LIGHT NE FLOW TO THE S OF THE HI CENTER LINGERING OVER
ONTARIO. BUT WITH PWAT FALLING AOB 0.25 INCH...WL TEND TOWARD THE LO
END OF GUIDANCE FOR THE INTERIOR SHELTERED LOCATIONS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 409 AM EDT TUE APR 26 2016
SPLIT FLOW ACROSS NORTH AMERICA. SHARP TROUGH IN THE NORTHERN POLAR
JET STREAM PERSISTS OVER EASTERN CANADA MOST OF THE WEEK. STRONG
TROUGH IN THE SOUTHERN STREAM PUSHING ACROSS THE WESTERN CONUS ATTM
SHEARS OUT WED INTO THU AS IT PUSHES INTO CONFLUENT FLOW ON WESTERN
EDGE OF THE EASTERN CANADA UPPER TROUGH. ANOTHER TROUGH MOVES ACROSS
WESTERN CONUS FRIDAY AND AS THAT SYSTEM LIFTS TOWARD GREAT LAKES LATE
IN THE WEEKEND COULD SEE SOME LIGHT PRECIPITATION. APPEARS COOLER
AND UNSETTLED WEATHER MAY LINGER EARLY NEXT WEEK AS THIS UPPER LOW
MEANDERS OVER THE GREAT LAKES. LATEST CPC FORECAST THEN SHOWS
GREATER CHANCES FOR ABOVE NORMAL TEMPS AND BELOW NORMAL PRECIP SETS
UP FOR MAY 3RD THROUGH MAY 8TH.
AS IT HAS LOOKED LIKE FOR A WHILE...MAIN SFC FEATURE THIS WEEK WILL
BE HIGH PRESSURE VCNTY OF HUDSON BAY WITH RIDGING EXTENDING OVER THE
UPPER GREAT LAKES. AS THE SHORTWAVE TROUGH CURRENTLY MOVING ACROSS
THE ROCKIES TO THE PLAINS TODAY LIFTS TOWARD UPPER GREAT LAKES WED
NIGHT INTO THU...SHOULD SEE INCREASING MID CLOUDS...ESPECIALLY OVER
SOUTH HALF OF CWA. WEAKENING FORCING ALONG WITH SOUNDINGS SHOWING
DRY AIR WITH THE HIGH BLO 700MB INDICATES MINIMAL CHANCES OF RAIN
OVER SOUTH CENTRAL ON THU. WEAKENING SYSTEM DEPARTS THU NIGHT THEN
COULD SEE INCREASING MID CLOUDS AGAIN FRI AS ANOTHER SYSTEM SHEARS
OUT WHILE MOVING FM THE CENTRAL PLAINS TOWARD THE STRONG LOW-LEVEL
RIDGE. GRADUALLY WARMING H85 TEMPS SHOULD ALLOW TEMPS INLAND TO
SLOWLY WARM THROUGH THE 50S TO POSSIBLY LOWER 60S BY FRI OR SAT.
GRADIENT NORTHEAST WINDS OUT OF THE HIGH WILL KEEP LK SUPERIOR SHORE
MAINLY IN THE 40S. WITH THE HIGH AND DRY AIRMASS IN VCNTY CONTINUE
TO PREFER NIGHTTIME TEMPS AT OR BLO FREEZING INLAND FOR THE REST OF
THE WEEK. DRY AIR SHOULD ALSO LEAD TO LOW TD/RH IN THE AFTN. WINDS
FOR MOST PART LOOK LIGHT SO EVEN THOUGH FIRE WEATHER CONCERNS WILL
BE INCREASING...THEY SHOULD BE KEPT IN CHECK.
CONSENSUS CONTINUES TO SHOW SLIGHT CHANCE POPS LATER IN THE WEEKEND
AS YET ANOTHER UPPER TROUGH MOVES TOWARD GREAT LAKES. PREVIOUS ECMWF
WAS SHOWING SYSTEM BEGINNING TO AFFECT AREA AS EARLY AS SAT NIGHT
BUT 00Z RUN DELAYS THE WEAKENING SYSTEM UNTIL LATE SUN INTO SUN
NIGHT/MON. GFS AND GEM-NH ARE SHUNTED MORE TO THE SOUTH...WHICH
MAKES SENSE GIVEN THE STRONG DRY HIGH PRESSURE PERSISTING. OVERALL
NOT LOOKING LIKE MUCH OF A CHANCE FOR RAIN FOR THE EXTENDED PERIOD
UNTIL EARLY NEXT WEEK...MAYBE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 229 PM EDT TUE APR 26 2016
VFR CONDITIONS WILL PERSIST THROUGH THE TAF PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 401 AM EDT TUE APR 26 2016
ENE WINDS UP TO 25-30 KTS OVER THE LAKE THIS MORNING...STRONGEST
OVER THE W...WILL DIMINISH THROUGH THE DAY TO UNDER 20 KTS AS A HI
PRES RIDGE BUILDS S THRU ONTARIO AND THE PRES GRADIENT WEAKENS. E TO
NE WINDS GENERALLY UNDER 20-25KT WILL THEN PREVAIL THRU SAT TO THE S
OF PERSISTENT HI PRES NEAR HUDSON BAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...TITUS
MARINE...KC
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
432 PM CDT TUE APR 26 2016
.Discussion...
Issued at 432 PM CDT TUE APR 26 2016
Convection got started early this morning in response to a little
vorticity max crossing a stalled front roughly along I-70, then the
low level jet kicked in and helped organize the early morning cells
into a progressive bow echo that moved across Missouri, roughly
along a line from St Joseph and Kansas City east-southeast through
Sedalia and Boonville. Rain totals of 1 to 2 inches, with locally
higher amounts, where noted along the path of the bow echo along
with some hail and wind reports, which will all factor into the
forecast for this evening. Otherwise, the bow echo has left behind a
significantly strong enough cold pool to push the stalled front from
I-70 south of the forecast region this afternoon, placing the
outflow boundary across Allen and Bourbon counties in Kansas just to
the southwest of our area, wrapping back up into the surface low
still located across central Kansas. This outflow boundary will be
the focus for more convection late this afternoon and evening.
Rest of the afternoon...Atmospheric recovery along the outflow
boundary, and points southwest, have returned into the 3000+ J/KG
range with effective southwest shear values of 40+ knots. This has
proven more than sufficient to result in severe thunderstorms just to
our west with convection starting to bubble up again in south
central Kansas along the dry line -extending south from the Wichita-
and also along the outflow boundary from Concordia, KS southeast to
Mound City, KS. However currently, steering winds up through 850mb
are from due south with 700mb winds south-southeast. As a result the
storms are lifting north-northeast so it will take till some time
for more than isolated thunderstorm activity to spread back across
our section of eastern Kansas and western Missouri. As the parent
upper level trough lifts and pivots late tonight it will become
increasingly negatively tilted, allowing more cold air in aloft thus
keeping the atmosphere unstable well into the overnight hours. This
could help fuel storms late into the overnight hours, keeping the
severe potential going late into the night as the low level jet veers
over into northwest Missouri. As a result, severe weather is
favorable for both damaging winds and large hail along with isolated
tornadoes both early this evening and late tonight. Expect storms to
persist through much of the night with ongoing activity possibly
lingering through sunrise Wednesday. Additionally, heavy rain is
expected to accompany these storms, and given the rainfall this
morning -especially across northwestern Missouri and northeast
Kansas- we have issued a flash flood watch for tonight to cover areas
along the state line.
Speaking of Wednesday...morning activity should be lifting northeast
and then likely result in a break in convection by the late morning
hours. However, the parent upper level trough will be pivoting
across above northwest Missouri with cold air sliding in aloft.
Resulting steepening lapse rates and could result in some low topped
thunderstorms, particularly in northwest Missouri and adjacent areas
of northeast Kansas. However, working against these low topped
storms will be the fact that the parent low will push the jet axis
east putting the better shear to the east of where the low top
storms would be expected. But, this still leaves the possibility open
for low topped severe weather in areas near the Iowa border east and
southeast into northeast and central Missouri Wednesday afternoon.
Any stormy activity Wednesday will likely continue to the northeast
thus leaving the region storm free by Thursday.
Attention then turns towards the weekend as another trough exits the
Desert Southwest by moving northeast across the Plains States. This
trough currently looks to be trending just far enough south to take
the focus for severe weather and put it to our south. But, we could
still get plenty of storms starting again Friday and lasting through
at least Saturday with more storms possible into Sunday. We will
want to watch for flooding potential given the rainfall totals
expected this work week, but currently the sever threat for the
weekend looks low at this time.
&&
.Aviation...(For the 18Z TAFS through 18Z Wednesday Afternoon)
Issued at 1231 PM CDT TUE APR 26 2016
VFR conditions have developed across the western Missouri terminals
late this morning into the early afternoon hours. The VFR conditions
will persist into the mid and late afternoon hours, but then another
round of thunderstorms is expected to develop in Kansas late this
afternoon, moving east into Missouri this evening. Current thoughts
are that the strongest storms will affect the terminals between 10 PM
and 1 AM. Storms could persist through the early morning hours before
they scatter out in the mid to late morning hours. Have only lowered
CIGs into the MVFR range, but might need to amend later as storms
develop and CIG height`s firm up.
&&
.EAX Watches/Warnings/Advisories...
KS...Flash Flood Watch from 9 PM CDT this evening through Wednesday
morning for KSZ025-057-060-102>105.
MO...Flash Flood Watch from 9 PM CDT this evening through Wednesday
morning for MOZ001>004-011>014-020>022-028>030-037-038-043-
044-053-054.
&&
$$
Discussion...Cutter
Aviation...Cutter
[top]
Area Forecast Discussion
National Weather Service Saint Louis MO
408 PM CDT TUE APR 26 2016
.SHORT TERM... (Through Late Tonight)
Issued at 332 PM CDT Tue Apr 26 2016
Current bowing convective system over SW IL has a well established
cold pool and will continue to move east into the western OH
Valley into a large region of unstable air in advance of it. The
deep convective line with any severe threat should clear the area by
500 pm with trailing stratiform rain clearing the CWA by early
evening. A prominent outflow boundary with the convective system,
which should have completely moved through the CWA by 00z, has
largely stabilized the air mass to boundary layer based storms in
its wake. I will retain some low chance pops this evening on the
fringes of our CWA however I think the vast majority of the
evening in the wake of the present system will be dry. Current
thinking is that overnight we will see a MCS that has evolved
across the Plains early this evening, move west to east into central
and finally eastern MO in the predawn hours. Additional showers
and thunderstorms could develop late this evening and overnight
ahead of the aforementioned progressive Plains MCS in response to
the LLJ and WAA along north of the retreating outflow boundary/warm
front composite. There will be a severe threat with this overnight
activity given MUCAPE of 1000+ j/kg and increasing southwesterly
deep layer shear, but not nearly as great as the system that moved
through today.
Glass
.LONG TERM... (Wednesday through Next Tuesday)
Issued at 332 PM CDT Tue Apr 26 2016
A little unclear how everything will pan out on Wednesday. There
will likely be ongoing convection from a decaying MCS over parts
of eastern MO in the morning that will move into IL. However it
does appear that there will be sufficient air mass recovery in the
wake of the morning convection. How much and the most favored
corridors are hard to say. Mid level lapse rates will remain steep
and heating should lead to SBCAPE of at least 1500 j/kg over parts
of central MO by early afternoon. The combination of the east-northeast
rotating short wave trof and large scale ascent, and the attendant
advancing cold front should result in thunderstorm development
along/ahead of the cold front by mid afternoon. Coverage should
then increase through the remainder of the afternoon, with storms
persisting into the evening as the front and trof progress east.
We will probably see a mixed convective mode with all severe
weather threats. Most of the activity should have moved out of the
CWA by 06z Thursday.
The trof will be lifting to the northeast on Thursday with the
cold front advancing into the OH/TN Valley region. Present
indications are that increasingly deep westerly flow in the wake
of the front will lead to good drying and little if any
precipitation.
Next round of showers and thunderstorms looks to unfold Friday
night into the weekend. First with the LLJ, WAA, and a lead
impulse Friday night/Saturday and then with another formidable
upper trof and attendant cold front Saturday night into Sunday.
Glass
&&
.AVIATION... (For the 12z TAFs through 12z Wednesday Morning)
Issued at 645 AM CDT Tue Apr 26 2016
Outside of some patchy MVFR CIGs in the north around UIN, VFR
conditions (outside of TSRA) are expected to prevail for the TAF
sites thru this evening. A cluster of TSRA is expected to roll
down from the KS-MO-NE junction this morning and affect COU and
the STL metro sites later this morning and early afternoon. A
brief period of gusty winds at the onset is also expected. A
frontal boundary is then anticipated to stall just north of I-70
for tonight and should promote low CIG formation for areas to the
north, including UIN, with MVFR CIGs returning there and perhaps
dropping into IFR category. Widespread rain and TSRA is then
expected to overspread the region later this evening and
overnight.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
[top]
Area Forecast Discussion
National Weather Service Springfield MO
250 PM CDT TUE APR 26 2016
.SHORT TERM...(This evening through Wednesday)
Ongoing thunderstorms were becoming more outflow structured across
southwest and south central Missouri this afternoon. This will
lead to further weakening with time, and we may consider
cancelling the Severe Thunderstorm Watch early.
The main show will occur tonight as a line of thunderstorms
approaches the Kansas and Missouri state line toward midnight.
We think a few of these storms could become organized, with the
potential for damaging wind gusts and small hail. With 0 to 3 km
shear vectors screaming to the north northeast at 40 to 45 knots,
any northwest to southeast oriented line segments will have the
chance of spinning up some meso-vorts with a tornado risk.
However, it`s quite uncertain that any segments will evolve into
this northwest to southeast structure. This is more of a short
term forecast challenge.
Storms are expected to continue through the Highway 65 corridor,
and should weaken as they approach the eastern Ozarks.
Additional storms will possible Wednesday as the main cold front
shifts through southern Missouri during the daytime hours. There
is a severe risk for hail and wind east of Highway 65. All
precipitation should exit the Ozarks Wednesday evening.
.LONG TERM...(Thursday through Tuesday)
A small window of quiet weather is expected Thursday into Friday
with mild temperatures.
The risk for organized storms will ramp up Friday night into
Saturday, as another negatively tilted storm system approaches
from the west.
This system will need to be monitored closely as several
ingredients could come together for an episode of severe
thunderstorms. There doesn`t appear to be any potential negatives
for Friday night and Saturday`s set up at the moment.
Sunday into Monday the pattern would offer another window of quiet
weather with mild temperatures.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Pilots flying in and out of the southwest Missouri airports will
need to monitor the radar today and tonight.
A big storm system was approaching the region from the west, which
will force showers and thunderstorms later today and tonight. Some
thunderstorms were already ongoing across central Missouri, and
are expected to slowly drift into far southern Missouri by this
afternoon.
Surface winds could be gusty at times this afternoon.
If any storms directly impacts an airfield, look for significantly
reduced flight conditions, especially if some of these storms
become severe.
Safe Travels.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Cramer
LONG TERM...Cramer
AVIATION...Cramer
Area Forecast Discussion
National Weather Service Springfield MO
250 PM CDT TUE APR 26 2016
.SHORT TERM...(This evening through Wednesday)
Ongoing thunderstorms were becoming more outflow structured across
southwest and south central Missouri this afternoon. This will
lead to further weakening with time, and we may consider
cancelling the Severe Thunderstorm Watch early.
The main show will occur tonight as a line of thunderstorms
approaches the Kansas and Missouri state line toward midnight.
We think a few of these storms could become organized, with the
potential for damaging wind gusts and small hail. With 0 to 3 km
shear vectors screaming to the north northeast at 40 to 45 knots,
any northwest to southeast oriented line segments will have the
chance of spinning up some meso-vorts with a tornado risk.
However, it`s quite uncertain that any segments will evolve into
this northwest to southeast structure. This is more of a short
term forecast challenge.
Storms are expected to continue through the Highway 65 corridor,
and should weaken as they approach the eastern Ozarks.
Additional storms will possible Wednesday as the main cold front
shifts through southern Missouri during the daytime hours. There
is a severe risk for hail and wind east of Highway 65. All
precipitation should exit the Ozarks Wednesday evening.
.LONG TERM...(Thursday through Tuesday)
A small window of quiet weather is expected Thursday into Friday
with mild temperatures.
The risk for organized storms will ramp up Friday night into
Saturday, as another negatively tilted storm system approaches
from the west.
This system will need to be monitored closely as several
ingredients could come together for an episode of severe
thunderstorms. There doesn`t appear to be any potential negatives
for Friday night and Saturday`s set up at the moment.
Sunday into Monday the pattern would offer another window of quiet
weather with mild temperatures.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Pilots flying in and out of the southwest Missouri airports will
need to monitor the radar today and tonight.
A big storm system was approaching the region from the west, which
will force showers and thunderstorms later today and tonight. Some
thunderstorms were already ongoing across central Missouri, and
are expected to slowly drift into far southern Missouri by this
afternoon.
Surface winds could be gusty at times this afternoon.
If any storms directly impacts an airfield, look for significantly
reduced flight conditions, especially if some of these storms
become severe.
Safe Travels.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Cramer
LONG TERM...Cramer
AVIATION...Cramer
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1232 PM CDT TUE APR 26 2016
.Discussion...
Issued at 416 AM CDT TUE APR 26 2016
Early morning elevated convection will continue to fire south of a
stationary frontal boundary draped across northeast Kansas and
northern Missouri. A stout EML will continue to support modest
instability with further destabilization through the morning hours.
Storms early on will be relatively isolated and should remain north
of the I-70 corridor until daybreak. Overnight convection has been
slow to strengthen given the lack of instability, though should
start to see more widespread development in the early to mid morning
hours. A larger cluster of storms developing over north central
Kansas, where more supportive instability is present, will likely
generate a cold pool sufficient enough to steer nearby convection to
the southeast. As these elevated storms strengthen after daybreak,
some storms may produce large hail until the mid morning.
As this activity slides to the southeast through the late morning to
early afternoon, there should be a bit of a break in the activity
until the late afternoon and early evening hours. The anticipated
deep upper low will center across western Kansas while at the
surface, a dryline will reside from central Texas up to south
central Nebraska. Morning convection may limit instability to a
degree, though cloud cover should thin out enough to generate
surface based CAPE values over 2000 Jkg by the mid afternoon. More
robust convection will fire along the dry line well to the west of
the area through the early afternoon. This convection will then
slide into eastern Kansas and western Missouri by the late
afternoon. Will also need to monitor the potential for convection
ahead of the dryline within an area of surface convergence. As the
storms over eastern Kansas approach the area, will likely transition
to a linear mode with bowing segments. Large hail and damaging winds
will be the primary hazards, particularly for western Missouri,
though a few embedded tornadoes cannot be ruled out.
The next round of activity, which could be more pronounced for the
CWA, arrives during Wednesday as the dryline advances toward eastern
Kansas. Modest instability looks to develop across eastern Kansas
along with central and southwest Missouri as previous convection
clears out. Most of the expected convection should develop over
central and eastern Missouri, though will need to monitor points
west, particularly northwest Missouri as the stacked low could
produce a few tornadoes.
The active pattern will subside temporarily heading into Thursday
and Friday, though another upper low will deepen across the
southwest during this time. Could see late week convection by late
Friday as a warm front lifts north. A few rounds of storms with
potential severe storms will then develop through the weekend as the
surface low lifts to the northwest into the Central Plains.
&&
.Aviation...(For the 18Z TAFS through 18Z Wednesday Afternoon)
Issued at 1231 PM CDT TUE APR 26 2016
VFR conditions have developed across the western Missouri terminals
late this morning into the early afternoon hours. The VFR conditions
will persist into the mid and late afternoon hours, but then another
round of thunderstorms is expected to develop in Kansas late this
afternoon, moving east into Missouri this evening. Current thoughts
are that the strongest storms will affect the terminals between 10 PM
and 1 AM. Storms could persist through the early morning hours before
they scatter out in the mid to late morning hours. Have only lowered
CIGs into the MVFR range, but might need to amend later as storms
develop and CIG height`s firm up.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...Welsh
Aviation...Cutter
Area Forecast Discussion
National Weather Service Springfield MO
1228 PM CDT TUE APR 26 2016
...AVIATION UPDATE...
.SYNOPSIS...
Issued at 251 AM CDT Tue Apr 26 2016
Convection starting to develop along a west east boundary across
northeast KS and west central MO near the I-70 corridor. Pretty
decent elevated mixed layer was located along and south of the
boundary and developing convection including our forecast area.
Surface low was located over the high plains with dryline from
western Kansas into the panhandle of OK and TX. South-southwest
low level jet and mid level diffluent flow was aiding in the
developing convection.
This is going to be a busy weather day/night for our CWA and
neighboring CWA`s to the west and will be the main focus with this
forecast package.
&&
.SHORT TERM...(Today and tonight)
Issued at 251 AM CDT Tue Apr 26 2016
Early morning convection will continue to increase north of the
CWA prior to sunrise nearer to the surface boundary. This activity
will gradually shift east today over mostly northern and central
MO, possibly affecting our central MO counties later today.
Further south within the EML, instability will increase
significantly with CAPES in excess of 3000 j/kg developing. Have
my doubts as to whether we will freely convect given the strength
of the thermal cap in place without a trigger, but will keep in
low end pops just in case. Best chance will be over central MO
where some outflow or ongoing convection may move into the area.
Dryline out west is likely to get active by midday as upper level
jet impinges on the central/southern plains and weakens the EML.
By late in the afternoon, the shear starts to become fairly strong
to our west and the combination with the strong instability
supports the moderate risk of severe storms from southern Nebraska
into central Kansas and Oklahoma. The best chances for supercells
moving into our area will be this evening and over our western
CWA, before they start to congeal into more of line segments. The
primary severe risk after that occurs will be damaging wind,
although we could still see tornadoes develop out of these line
segments through the rest of the evening and overnight hours.
.LONG TERM...(Wednesday through Monday)
Issued at 251 AM CDT Tue Apr 26 2016
Wednesday looks like a messy forecast. There will probably be
ongoing convection at 12z Wed to start the morning, but models are
clearing this out by late morning. With the front still to the
west, can enough instability develop in the wake of the first
complex for convection to refire in the afternoon. Best bet will
be over our eastern CWA, where the higher surface dewpoints will
hang around the longest. Current day 2 outlook shows this with
slight risk over the eastern half of our CWA. Would expect this
activity to clear our eastern CWA by mid to late evening.
There should be a brief break from the convective potential on
Thursday, before the active pattern brings in the next system on
Friday into the weekend. This has the potential to be a wet
weekend with closed upper level low sitting over the central U.S.
for quite awhile.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Pilots flying in and out of the southwest Missouri airports will
need to monitor the radar today and tonight.
A big storm system was approaching the region from the west, which
will force showers and thunderstorms later today and tonight. Some
thunderstorms were already ongoing across central Missouri, and
are expected to slowly drift into far southern Missouri by this
afternoon.
Surface winds could be gusty at times this afternoon.
If any storms directly impacts an airfield, look for significantly
reduced flight conditions, especially if some of these storms
become severe.
Safe Travels.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SYNOPSIS...Lindenberg
SHORT TERM...Lindenberg
LONG TERM...Lindenberg
AVIATION...Cramer
Area Forecast Discussion
National Weather Service Springfield MO
1228 PM CDT TUE APR 26 2016
...AVIATION UPDATE...
.SYNOPSIS...
Issued at 251 AM CDT Tue Apr 26 2016
Convection starting to develop along a west east boundary across
northeast KS and west central MO near the I-70 corridor. Pretty
decent elevated mixed layer was located along and south of the
boundary and developing convection including our forecast area.
Surface low was located over the high plains with dryline from
western Kansas into the panhandle of OK and TX. South-southwest
low level jet and mid level diffluent flow was aiding in the
developing convection.
This is going to be a busy weather day/night for our CWA and
neighboring CWA`s to the west and will be the main focus with this
forecast package.
&&
.SHORT TERM...(Today and tonight)
Issued at 251 AM CDT Tue Apr 26 2016
Early morning convection will continue to increase north of the
CWA prior to sunrise nearer to the surface boundary. This activity
will gradually shift east today over mostly northern and central
MO, possibly affecting our central MO counties later today.
Further south within the EML, instability will increase
significantly with CAPES in excess of 3000 j/kg developing. Have
my doubts as to whether we will freely convect given the strength
of the thermal cap in place without a trigger, but will keep in
low end pops just in case. Best chance will be over central MO
where some outflow or ongoing convection may move into the area.
Dryline out west is likely to get active by midday as upper level
jet impinges on the central/southern plains and weakens the EML.
By late in the afternoon, the shear starts to become fairly strong
to our west and the combination with the strong instability
supports the moderate risk of severe storms from southern Nebraska
into central Kansas and Oklahoma. The best chances for supercells
moving into our area will be this evening and over our western
CWA, before they start to congeal into more of line segments. The
primary severe risk after that occurs will be damaging wind,
although we could still see tornadoes develop out of these line
segments through the rest of the evening and overnight hours.
.LONG TERM...(Wednesday through Monday)
Issued at 251 AM CDT Tue Apr 26 2016
Wednesday looks like a messy forecast. There will probably be
ongoing convection at 12z Wed to start the morning, but models are
clearing this out by late morning. With the front still to the
west, can enough instability develop in the wake of the first
complex for convection to refire in the afternoon. Best bet will
be over our eastern CWA, where the higher surface dewpoints will
hang around the longest. Current day 2 outlook shows this with
slight risk over the eastern half of our CWA. Would expect this
activity to clear our eastern CWA by mid to late evening.
There should be a brief break from the convective potential on
Thursday, before the active pattern brings in the next system on
Friday into the weekend. This has the potential to be a wet
weekend with closed upper level low sitting over the central U.S.
for quite awhile.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Pilots flying in and out of the southwest Missouri airports will
need to monitor the radar today and tonight.
A big storm system was approaching the region from the west, which
will force showers and thunderstorms later today and tonight. Some
thunderstorms were already ongoing across central Missouri, and
are expected to slowly drift into far southern Missouri by this
afternoon.
Surface winds could be gusty at times this afternoon.
If any storms directly impacts an airfield, look for significantly
reduced flight conditions, especially if some of these storms
become severe.
Safe Travels.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SYNOPSIS...Lindenberg
SHORT TERM...Lindenberg
LONG TERM...Lindenberg
AVIATION...Cramer
Area Forecast Discussion
National Weather Service Springfield MO
651 AM CDT TUE APR 26 2016
.SYNOPSIS...
Issued at 251 AM CDT Tue Apr 26 2016
Convection starting to develop along a west east boundary across
northeast KS and west central MO near the I-70 corridor. Pretty
decent elevated mixed layer was located along and south of the
boundary and developing convection including our forecast area.
Surface low was located over the high plains with dryline from
western Kansas into the panhandle of OK and TX. South-southwest
low level jet and mid level diffluent flow was aiding in the
developing convection.
This is going to be a busy weather day/night for our CWA and
neighboring CWA`s to the west and will be the main focus with this
forecast package.
&&
.SHORT TERM...(Today and tonight)
Issued at 251 AM CDT Tue Apr 26 2016
Early morning convection will continue to increase north of the
CWA prior to sunrise nearer to the surface boundary. This activity
will gradually shift east today over mostly northern and central
MO, possibly affecting our central MO counties later today.
Further south within the EML, instability will increase
significantly with CAPES in excess of 3000 j/kg developing. Have
my doubts as to whether we will freely convect given the strength
of the thermal cap in place without a trigger, but will keep in
low end pops just in case. Best chance will be over central MO
where some outflow or ongoing convection may move into the area.
Dryline out west is likely to get active by midday as upper level
jet impinges on the central/southern plains and weakens the EML.
By late in the afternoon, the shear starts to become fairly strong
to our west and the combination with the strong instability
supports the moderate risk of severe storms from southern Nebraska
into central Kansas and Oklahoma. The best chances for supercells
moving into our area will be this evening and over our western
CWA, before they start to congeal into more of line segments. The
primary severe risk after that occurs will be damaging wind,
although we could still see tornadoes develop out of these line
segments through the rest of the evening and overnight hours.
.LONG TERM...(Wednesday through Monday)
Issued at 251 AM CDT Tue Apr 26 2016
Wednesday looks like a messy forecast. There will probably be
ongoing convection at 12z Wed to start the morning, but models are
clearing this out by late morning. With the front still to the
west, can enough instability develop in the wake of the first
complex for convection to refire in the afternoon. Best bet will
be over our eastern CWA, where the higher surface dewpoints will
hang around the longest. Current day 2 outlook shows this with
slight risk over the eastern half of our CWA. Would expect this
activity to clear our eastern CWA by mid to late evening.
There should be a brief break from the convective potential on
Thursday, before the active pattern brings in the next system on
Friday into the weekend. This has the potential to be a wet
weekend with closed upper level low sitting over the central U.S.
for quite awhile.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 651 AM CDT Tue Apr 26 2016
Rather low confidence in overall forecast, especially with respect
to the details. Short term models want to lift MVFR ceilings from
eastern Oklahoma and Arkansas northward into the taf sites. This
has been a trend for the last several runs and latest satellite
imagery also showing this trend, so expect a period of MVFR
ceilings this morning. Otherwise expect VFR flight conditions through
the remainder of the taf period with MVFR/IFR possible in
convection later today and tonight.
In terms of convection an area of thunderstorms over northeast
Kansas is expected to drop southeast into central Missouri by
mid-day. Expect this activity to remain north of the taf sites
though, but did include some VCTS this afternoon. Otherwise,
better chances will come this evening as convection across Kansas
and Oklahoma pushes eastward. Timing still a little uncertain but
will most likely affect KJLN during the early to mid evening and
KSGF and KBBG late evening to midnight or shortly there after.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SYNOPSIS...Lindenberg
SHORT TERM...Lindenberg
LONG TERM...Lindenberg
AVIATION...Raberding
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
645 AM CDT TUE APR 26 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 406 AM CDT Tue Apr 26 2016
A Rex Block pattern exists over the CONUS Rockies and Canadian
Prairie with a weak RIDGE over our region. A surface frontal
boundary at 07z extended from just south of Chicagoland west-
southwestward to just north of Quincy and near Kansas City. This
front, in the absence of any upper support and low level jet, will
be the primary focus for any convection that might develop thru late
this morning. Such as it is, a capping inversion has largely
suppressed the attempted convection in our region and so only a
slight chance is anticipated during this time.
The best focus thru early this morning will be to our west in
northeast Kansas and southeast Nebraska, where there will be a low
level jet and radar and satellite shows this is where the breaking
of the capping inversion has been most successful.
Short-term model guidance seems to have a loose consensus on the
convection that develops to our west congealing and then tracking
east along what should be a slowly southward sagging front over our
way. Have followed these trends for now with increasing PoPs into
central MO for late this morning, sliding into STL metro during
midday-early afternoon, and then into southern IL during the
afternoon. Peaked PoPs at 50% for now, but these will need to be
increased as confidence of this event waxes.
This convective event for late this morning and afternoon, and
especially the leading or eastern edge of it, will have some
potential for severe with marginal bulk shear values and CAPE of
around 2000 J/kg. It will very much depend on how organized the
convection can get early this morning before heading east.
Corresponding with a southward moving front and increased cloudiness
associated with this convective event later today, have edged back
on max temps, still preferring the MAV MOS values from upper 70s in
northeast MO and west-central IL to 80-85 elsewhere. Again, this
is all conditional on the rain event, so these will probably need
further massaging.
TES
.LONG TERM... (Tonight through Monday)
Issued at 406 AM CDT Tue Apr 26 2016
A complex forecast in the short term with multiple rounds of storms
thru mid-week.
Convection today will largely determine how events tonight will
unfold. In general, have trended twd the NSSL WRF/local 4km WRF
early in the period, then twd the GFS/ECMWF late tonight into Wed
morning. The 06z/26 NAM actually trended twd this idea as well.
The outflow boundary from today`s convection is expected to push any
activity S of the CWA this evening. As the trof over the Plains
becomes more negatively tilted and the sfc boundary lifting nwd back
into the area, expect more storms to move into the region late
tonight. Mdls still prog near 1000 J/kg elevated CAPE, with enuf
deep layer shear to support a threat for severe storms, mainly large
hail given elevated storms. Flooding will be another threat tonight
if storms today evolve as anticipated, with storms tonight traveling
over the same region. Due to uncertainty in precip today and
tonight, have held off on any headlines attm.
Expect convection to be ongoing at the beginning of the period Wed
along and N of the fnt. This convection is expected to push nwd as
the upper trof rotates nwd. The wrmfnt associated with this system
is expected to be draped across the central portions of the CWA and
will provide a focus for storm development Wed afternoon as a s/w
rotates thru the base of the trof. Cloud cover, and therefore
heating, near the fnt are still uncertain with mdls depicting mid
level warming that may keep the region capped. If this cap can be
broken, supercells with large hail will be possible along this fnt,
with what appears to be a triple point in central MO.
The bulk of what develops shud be N of the area by around Midnight
Thurs, but have kept higher PoPs to account for timing differences.
Once this precip exits the area, expect much of Thurs and Fri dry.
Active weather returns this weekend with sfc ridge building into the
region on Mon bringing much cooler temps to the region.
Tilly
&&
.AVIATION... (For the 12z TAFs through 12z Wednesday Morning)
Issued at 645 AM CDT Tue Apr 26 2016
Outside of some patchy MVFR CIGs in the north around UIN, VFR
conditions (outside of TSRA) are expected to prevail for the TAF
sites thru this evening. A cluster of TSRA is expected to roll
down from the KS-MO-NE junction this morning and affect COU and
the STL metro sites later this morning and early afternoon. A
brief period of gusty winds at the onset is also expected. A
frontal boundary is then anticipated to stall just north of I-70
for tonight and should promote low CIG formation for areas to the
north, including UIN, with MVFR CIGs returning there and perhaps
dropping into IFR category. Widespread rain and TSRA is then
expected to overspread the region later this evening and
overnight.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
554 AM CDT TUE APR 26 2016
.Discussion...
Issued at 416 AM CDT TUE APR 26 2016
Early morning elevated convection will continue to fire south of a
stationary frontal boundary draped across northeast Kansas and
northern Missouri. A stout EML will continue to support modest
instability with further destabilization through the morning hours.
Storms early on will be relatively isolated and should remain north
of the I-70 corridor until daybreak. Overnight convection has been
slow to strengthen given the lack of instability, though should
start to see more widespread development in the early to mid morning
hours. A larger cluster of storms developing over north central
Kansas, where more supportive instability is present, will likely
generate a cold pool sufficient enough to steer nearby convection to
the southeast. As these elevated storms strengthen after daybreak,
some storms may produce large hail until the mid morning.
As this activity slides to the southeast through the late morning to
early afternoon, there should be a bit of a break in the activity
until the late afternoon and early evening hours. The anticipated
deep upper low will center across western Kansas while at the
surface, a dryline will reside from central Texas up to south
central Nebraska. Morning convection may limit instability to a
degree, though cloud cover should thin out enough to generate
surface based CAPE values over 2000 Jkg by the mid afternoon. More
robust convection will fire along the dry line well to the west of
the area through the early afternoon. This convection will then
slide into eastern Kansas and western Missouri by the late
afternoon. Will also need to monitor the potential for convection
ahead of the dryline within an area of surface convergence. As the
storms over eastern Kansas approach the area, will likely transition
to a linear mode with bowing segments. Large hail and damaging winds
will be the primary hazards, particularly for western Missouri,
though a few embedded tornadoes cannot be ruled out.
The next round of activity, which could be more pronounced for the
CWA, arrives during Wednesday as the dryline advances toward eastern
Kansas. Modest instability looks to develop across eastern Kansas
along with central and southwest Missouri as previous convection
clears out. Most of the expected convection should develop over
central and eastern Missouri, though will need to monitor points
west, particularly northwest Missouri as the stacked low could
produce a few tornadoes.
The active pattern will subside temporarily heading into Thursday
and Friday, though another upper low will deepen across the
southwest during this time. Could see late week convection by late
Friday as a warm front lifts north. A few rounds of storms with
potential severe storms will then develop through the weekend as the
surface low lifts to the northwest into the Central Plains.
&&
.Aviation...(For the 12Z TAFS through 12Z Wednesday Morning)
Issued at 545 AM CDT TUE APR 26 2016
Developing thunderstorms over NE Kansas will slide to the southeast
and should clip the KC metro through the early morning hours.
Visibility and ceilings will likely decrease to MVFR should the
storms drop far enough south as expected. This will be followed by a
break in the activity through much of the afternoon with conditions
returning to VFR. More widespread thunderstorms will then develop
ahead of a dryline over central Kansas and work their way into the
terminals this evening. Ceilings may periodically drop to IFR within
the stronger storms, though prevailing MVFR looks probable overall.
These will then begin to taper off toward the very end of the
forecast period.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...Welsh
Aviation...Welsh
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
416 AM CDT TUE APR 26 2016
.Discussion...
Issued at 416 AM CDT TUE APR 26 2016
Early morning elevated convection will continue to fire south of a
stationary frontal boundary draped across northeast Kansas and
northern Missouri. A stout EML will continue to support modest
instability with further destabilization through the morning hours.
Storms early on will be relatively isolated and should remain north
of the I-70 corridor until daybreak. Overnight convection has been
slow to strengthen given the lack of instability, though should
start to see more widespread development in the early to mid morning
hours. A larger cluster of storms developing over north central
Kansas, where more supportive instability is present, will likely
generate a cold pool sufficient enough to steer nearby convection to
the southeast. As these elevated storms strengthen after daybreak,
some storms may produce large hail until the mid morning.
As this activity slides to the southeast through the late morning to
early afternoon, there should be a bit of a break in the activity
until the late afternoon and early evening hours. The anticipated
deep upper low will center across western Kansas while at the
surface, a dryline will reside from central Texas up to south
central Nebraska. Morning convection may limit instability to a
degree, though cloud cover should thin out enough to generate
surface based CAPE values over 2000 Jkg by the mid afternoon. More
robust convection will fire along the dry line well to the west of
the area through the early afternoon. This convection will then
slide into eastern Kansas and western Missouri by the late
afternoon. Will also need to monitor the potential for convection
ahead of the dryline within an area of surface convergence. As the
storms over eastern Kansas approach the area, will likely transition
to a linear mode with bowing segments. Large hail and damaging winds
will be the primary hazards, particularly for western Missouri,
though a few embedded tornadoes cannot be ruled out.
The next round of activity, which could be more pronounced for the
CWA, arrives during Wednesday as the dryline advances toward eastern
Kansas. Modest instability looks to develop across eastern Kansas
along with central and southwest Missouri as previous convection
clears out. Most of the expected convection should develop over
central and eastern Missouri, though will need to monitor points
west, particularly northwest Missouri as the stacked low could
produce a few tornadoes.
The active pattern will subside temporarily heading into Thursday
and Friday, though another upper low will deepen across the
southwest during this time. Could see late week convection by late
Friday as a warm front lifts north. A few rounds of storms with
potential severe storms will then develop through the weekend as the
surface low lifts to the northwest into the Central Plains.
&&
.Aviation...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1236 AM CDT TUE APR 26 2016
Active next 24 hours with showers and storms expected to blossom
across eastern KS and western MO over the next 2 to 6 hours and
continue off and on into late morning. Some of these storms could be
strong. Another round of storms is expected Tuesday evening, which
will likely be in the form of a north-south oriented line that will
track slowly from eastern KS into western MO after dark.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...Welsh
Aviation...Hawblitzel
Area Forecast Discussion
National Weather Service Saint Louis MO
407 AM CDT TUE APR 26 2016
.SHORT TERM... (Through Late This Afternoon)
Issued at 406 AM CDT Tue Apr 26 2016
A Rex Block pattern exists over the CONUS Rockies and Canadian
Prairie with a weak RIDGE over our region. A surface frontal
boundary at 07z extended from just south of Chicagoland west-
southwestward to just north of Quincy and near Kansas City. This
front, in the absence of any upper support and low level jet, will
be the primary focus for any convection that might develop thru late
this morning. Such as it is, a capping inversion has largely
suppressed the attempted convection in our region and so only a
slight chance is anticipated during this time.
The best focus thru early this morning will be to our west in
northeast Kansas and southeast Nebraska, where there will be a low
level jet and radar and satellite shows this is where the breaking
of the capping inversion has been most successful.
Short-term model guidance seems to have a loose consensus on the
convection that develops to our west congealing and then tracking
east along what should be a slowly southward sagging front over our
way. Have followed these trends for now with increasing PoPs into
central MO for late this morning, sliding into STL metro during
midday-early afternoon, and then into southern IL during the
afternoon. Peaked PoPs at 50% for now, but these will need to be
increased as confidence of this event waxes.
This convective event for late this morning and afternoon, and
especially the leading or eastern edge of it, will have some
potential for severe with marginal bulk shear values and CAPE of
around 2000 J/kg. It will very much depend on how organized the
convection can get early this morning before heading east.
Corresponding with a southward moving front and increased cloudiness
associated with this convective event later today, have edged back
on max temps, still preferring the MAV MOS values from upper 70s in
northeast MO and west-central IL to 80-85 elsewhere. Again, this
is all conditional on the rain event, so these will probably need
further massaging.
TES
.LONG TERM... (Tonight through Monday)
Issued at 406 AM CDT Tue Apr 26 2016
A complex forecast in the short term with multiple rounds of storms
thru mid-week.
Convection today will largely determine how events tonight will
unfold. In general, have trended twd the NSSL WRF/local 4km WRF
early in the period, then twd the GFS/ECMWF late tonight into Wed
morning. The 06z/26 NAM actually trended twd this idea as well.
The outflow boundary from today`s convection is expected to push any
activity S of the CWA this evening. As the trof over the Plains
becomes more negatively tilted and the sfc boundary lifting nwd back
into the area, expect more storms to move into the region late
tonight. Mdls still prog near 1000 J/kg elevated CAPE, with enuf
deep layer shear to support a threat for severe storms, mainly large
hail given elevated storms. Flooding will be another threat tonight
if storms today evolve as anticipated, with storms tonight traveling
over the same region. Due to uncertainty in precip today and
tonight, have held off on any headlines attm.
Expect convection to be ongoing at the beginning of the period Wed
along and N of the fnt. This convection is expected to push nwd as
the upper trof rotates nwd. The wrmfnt associated with this system
is expected to be draped across the central portions of the CWA and
will provide a focus for storm development Wed afternoon as a s/w
rotates thru the base of the trof. Cloud cover, and therefore
heating, near the fnt are still uncertain with mdls depicting mid
level warming that may keep the region capped. If this cap can be
broken, supercells with large hail will be possible along this fnt,
with what appears to be a triple point in central MO.
The bulk of what develops shud be N of the area by around Midnight
Thurs, but have kept higher PoPs to account for timing differences.
Once this precip exits the area, expect much of Thurs and Fri dry.
Active weather returns this weekend with sfc ridge building into the
region on Mon bringing much cooler temps to the region.
Tilly
&&
.AVIATION... (For the 06z TAFs through 06z Tuesday Night)
Issued at 1152 PM CDT Mon Apr 25 2016
Still looks like thunderstorms will develop late tonight over
western MO and move east into central MO. These storms may affect
KCOU and possibly the St. Louis metro terminals through mid
morning. A cold front currently over southeast Missouri and
northern Missouri will move southeast which could produce
additional thunderstorms during the day on Thursday. Any
thunderstorms that move over an airport could produce MVFR or
brief IFR ceilings and visibilities. There is also the possibility
that a few storms could produce hail and wind gusts over 50 kts.
Specifics for KSTL: There is a chance of showers and thunderstorms
through the period, particularly late Tuesday afternoon and
Tuesday night when a cold front will move into the area. Any
thunderstorms that move over the terminal could produce MVFR or
brief IFR ceilings and visibilities.
Britt
&&
.PRELIMINARY POINT TEMPS/POPS...
Saint Louis 82 64 80 58 / 50 80 80 50
Quincy 79 56 74 54 / 20 80 80 70
Columbia 81 61 80 54 / 50 80 70 30
Jefferson City 84 61 81 54 / 50 80 70 30
Salem 80 62 77 58 / 50 70 80 70
Farmington 81 61 77 56 / 50 80 80 50
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Springfield MO
251 AM CDT TUE APR 26 2016
.SYNOPSIS...
Issued at 251 AM CDT Tue Apr 26 2016
Convection starting to develop along a west east boundary across
northeast KS and west central MO near the I-70 corridor. Pretty
decent elevated mixed layer was located along and south of the
boundary and developing convection including our forecast area.
Surface low was located over the high plains with dryline from
western Kansas into the panhandle of OK and TX. South-southwest
low level jet and mid level diffluent flow was aiding in the
developing convection.
This is going to be a busy weather day/night for our CWA and
neighboring CWA`s to the west and will be the main focus with this
forecast package.
&&
.SHORT TERM...(Today and tonight)
Issued at 251 AM CDT Tue Apr 26 2016
Early morning convection will continue to increase north of the
CWA prior to sunrise nearer to the surface boundary. This activity
will gradually shift east today over mostly northern and central
MO, possibly affecting our central MO counties later today.
Further south within the EML, instability will increase
significantly with CAPES in excess of 3000 j/kg developing. Have
my doubts as to whether we will freely convect given the strength
of the thermal cap in place without a trigger, but will keep in
low end pops just in case. Best chance will be over central MO
where some outflow or ongoing convection may move into the area.
Dryline out west is likely to get active by midday as upper level
jet impinges on the central/southern plains and weakens the EML.
By late in the afternoon, the shear starts to become fairly strong
to our west and the combination with the strong instability
supports the moderate risk of severe storms from southern Nebraska
into central Kansas and Oklahoma. The best chances for supercells
moving into our area will be this evening and over our western
CWA, before they start to congeal into more of line segments. The
primary severe risk after that occurs will be damaging wind,
although we could still see tornadoes develop out of these line
segments through the rest of the evening and overnight hours.
.LONG TERM...(Wednesday through Monday)
Issued at 251 AM CDT Tue Apr 26 2016
Wednesday looks like a messy forecast. There will probably be
ongoing convection at 12z Wed to start the morning, but models are
clearing this out by late morning. With the front still to the
west, can enough instability develop in the wake of the first
complex for convection to refire in the afternoon. Best bet will
be over our eastern CWA, where the higher surface dewpoints will
hang around the longest. Current day 2 outlook shows this with
slight risk over the eastern half of our CWA. Would expect this
activity to clear our eastern CWA by mid to late evening.
There should be a brief break from the convective potential on
Thursday, before the active pattern brings in the next system on
Friday into the weekend. This has the potential to be a wet
weekend with closed upper level low sitting over the central U.S.
for quite awhile.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1145 PM CDT Mon Apr 25 2016
For the KSGF/KJLN/KBBG tafs: Scattered tstms are expected to
develop north of the taf sites over the next few hours close to
a warm front over northeast KS and northern MO. Some of this
activity may moves south toward the area by 12z-14z, but timing is
questionable. Will maintain vcts groups for KSGF and KJLN for now.
Low level moisture is expected to increase and have low end mvfr
or ifr ceilings at all sites toward 12z. Ceilings are expected to
lift between 15z-18z.
Additional storms are expected to develop late in the taf period
over the Plains and shift east into western MO.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SYNOPSIS...Lindenberg
SHORT TERM...Lindenberg
LONG TERM...Lindenberg
AVIATION...DSA
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1226 AM CDT TUE APR 26 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 06Z TAFS through 06Z Tuesday Night)
Issued at 1236 AM CDT TUE APR 26 2016
Active next 24 hours with showers and storms expected to blossom
across eastern KS and western MO over the next 2 to 6 hours and
continue off and on into late morning. Some of these storms could be
strong. Another round of storms is expected Tuesday evening, which
will likely be in the form of a north-south oriented line that will
track slowly from eastern KS into western MO after dark.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...CDB
Aviation...Hawblitzel
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1203 AM CDT TUE APR 26 2016
.UPDATE...
Issued at 914 PM CDT Mon Apr 25 2016
Have made some adjustments to PoP trends. Thunderstorms have had a
hard time developing over the CWA so far this evening as the 00Z
SGF sounding was showing a large inversion around 750mb. The RAP
is showing an increase in low level moisture convergence along
I-70 across western and central MO after midnight on the nose of a
40kt low level jet. This will be occuring at the same time a weak
shortwave will be approaching the area from the Central Plains.
Have shown an increase in scattered thunderstorms after midnight
over central Missouri that spreads into eastern Missouri towards
morning. There will be some risk for large hail with these storms
over central Missouri per the latest SPC outlook with MUCAPES of
1000-1500 J/kg and effective shear 30-35kts.
Going low temperatures still look good.
Britt
&&
.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 06z TAFs through 06z Tuesday Night)
Issued at 1152 PM CDT Mon Apr 25 2016
Still looks like thunderstorms will develop late tonight over
western MO and move east into central MO. These storms may affect
KCOU and possibly the St. Louis metro terminals through mid
morning. A cold front currently over southeast Missouri and
northern Missouri will move southeast which could produce
additional thunderstorms during the day on Thursday. Any
thunderstorms that move over an airport could produce MVFR or
brief IFR ceilings and visibilities. There is also the possibility
that a few storms could produce hail and wind gusts over 50 kts.
Specifics for KSTL: There is a chance of showers and thunderstorms
through the period, particularly late Tuesday afternoon and
Tuesday night when a cold front will move into the area. Any
thunderstorms that move over the terminal could produce MVFR or
brief IFR ceilings and visibilities.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Springfield MO
1159 PM CDT MON APR 25 2016
.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 06Z TAFS through 06Z Tuesday night)
Issued at 1145 PM CDT Mon Apr 25 2016
For the KSGF/KJLN/KBBG tafs: Scattered tstms are expected to
develop north of the taf sites over the next few hours close to
a warm front over northeast KS and northern MO. Some of this
activity may moves south toward the area by 12z-14z, but timing is
questionable. Will maintain vcts groups for KSGF and KJLN for now.
Low level moisture is expected to increase and have low end mvfr
or ifr ceilings at all sites toward 12z. Ceilings are expected to
lift between 15z-18z.
Additional storms are expected to develop late in the taf period
over the Plains and shift east into western MO.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Burchfield
LONG TERM...Griffin
AVIATION...DSA
Area Forecast Discussion...Updated
National Weather Service Saint Louis MO
915 PM CDT MON APR 25 2016
.UPDATE...
Issued at 914 PM CDT Mon Apr 25 2016
Have made some adjustments to PoP trends. Thunderstorms have had a
hard time developing over the CWA so far this evening as the 00Z
SGF sounding was showing a large inversion around 750mb. The RAP
is showing an increase in low level moisture convergence along
I-70 across western and central MO after midnight on the nose of a
40kt low level jet. This will be occuring at the same time a weak
shortwave will be approaching the area from the Central Plains.
Have shown an increase in scattered thunderstorms after midnight
over central Missouri that spreads into eastern Missouri towards
morning. There will be some risk for large hail with these storms
over central Missouri per the latest SPC outlook with MUCAPES of
1000-1500 J/kg and effective shear 30-35kts.
Going low temperatures still look good.
Britt
&&
.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 00z TAFs through 00z Tuesday Evening)
Issued at 619 PM CDT Mon Apr 25 2016
There is still some potential for scattered thunderstorms to
develop over the area this evening that could affect any of the
the terminals. This chance is too low however to include in any of
the TAFs at this point. Models are hinting that a complex of
storms could develop over western MO later tonight and move east
which would affect KCOU and possibly the St. Louis area terminals.
Have gone ahead and added VCTS at KCOU for a short period to
include this possibility. Cold front that currently extends from
southern Iowa into northern Missouri will move south into the area
by tomorrow afternoon. Additional scattered thunderstorms could
develop along it which could affect KCOU and the St. Louis area
terminals. Any thunderstorms that move over an airport could
produce MVFR or brief IFR ceilings and visibilities. There is
also the possibility that a few storms could produce hail and wind
gusts over 50 kts.
Specifics for KSTL: Have gone with a dry and VFR TAF for now,
however there will a 20-30 percent chance of thunderstorms through
the period. A cold front will move south to near the terminal
during the day tomorrow causing winds to shift to the southeast.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Springfield MO
645 PM CDT MON APR 25 2016
...00z Aviation Update...
.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 00Z TAFS through 00Z Tuesday evening)
Issued at 645 PM CDT Mon Apr 25 2016
VFR conditions can be expected at the start of this cycle. CIGs
will begin to lower later tonight and early tomorrow as stratus
build down takes over. To aid in this, a decent southerly surface
flow will continue to supply the area with plenty of low level
moisture. With the stratus build down, did go ahead and lower vis
into the MVFR range and dropped CIGs into IFR at least for a short
time early Tuesday.
Conditions will once again improve during the day to VFR by mid to
late afternoon. In terms of precipitation, low confidence at the
moment. Decided to keep only VCs going for now. The aforementioned
"decent" surface winds/flow may become a tad gusty tomorrow
afternoon over JLN. Speaking of wind, low level wind shear will be
present overnight tonight with an increasing LLJ, especially over
JLN and SGF.
&&
.SGF Watches/Warnings/Advisories...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Burchfield
LONG TERM...Griffin
AVIATION...Frye
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
644 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 00z TAFs through 00z Tuesday Evening)
Issued at 619 PM CDT Mon Apr 25 2016
There is still some potential for scattered thunderstorms to
develop over the area this evening that could affect any of the
the terminals. This chance is too low however to include in any of
the TAFs at this point. Models are hinting that a complex of
storms could develop over western MO later tonight and move east
which would affect KCOU and possibly the St. Louis area terminals.
Have gone ahead and added VCTS at KCOU for a short period to
include this possibility. Cold front that currently extends from
southern Iowa into northern Missouri will move south into the area
by tomorrow afternoon. Additional scattered thunderstorms could
develop along it which could affect KCOU and the St. Louis area
terminals. Any thunderstorms that move over an airport could
produce MVFR or brief IFR ceilings and visibilities. There is
also the possibility that a few storms could produce hail and wind
gusts over 50 kts.
Specifics for KSTL: Have gone with a dry and VFR TAF for now,
however there will a 20-30 percent chance of thunderstorms through
the period. A cold front will move south to near the terminal
during the day tomorrow causing winds to shift to the southeast.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
635 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 00Z TAFS through 00Z Tuesday Evening)
Issued at 635 PM CDT MON APR 25 2016
Front remains draped across the lower Missouri Valley this
evening and it will be this feature that serves as focusing
mechanism for developing shwrs/storms after midnight as the low-
level jet begins impinging upon the boundary. For now...best coverage
of storms looks to occur after the 08z time frame...and tempo groups
have been inserted for all terminals. As storms develop...IFR
conditions will remain possible through the mid-morning hrs before
conditions improve towards 14z. Otherwise...dry conditions to prevail
through much of the remaining daylight hrs with storms again becoming
likely after the conclusion of the fcst period.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...CDB
Aviation...32
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
635 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 00Z TAFS through 00Z Tuesday Evening)
Issued at 635 PM CDT MON APR 25 2016
Front remains draped across the lower Missouri Valley this
evening and it will be this feature that serves as focusing
mechanism for developing shwrs/storms after midnight as the low-
level jet begins impinging upon the boundary. For now...best coverage
of storms looks to occur after the 08z time frame...and tempo groups
have been inserted for all terminals. As storms develop...IFR
conditions will remain possible through the mid-morning hrs before
conditions improve towards 14z. Otherwise...dry conditions to prevail
through much of the remaining daylight hrs with storms again becoming
likely after the conclusion of the fcst period.
&&
.EAX Watches/Warnings/Advisories...
KS...None.
MO...None.
&&
$$
Discussion...CDB
Aviation...32
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
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
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 OMAHA/VALLEY NE
244 PM CDT TUE APR 26 2016
.SHORT TERM...(TONIGHT THROUGH FRIDAY)
ISSUED AT 243 PM CDT TUE APR 26 2016
POTENTIAL FOR SEVERE THUNDERSTORMS LOOMS THROUGH THIS EVENING.
SUBJECTIVE 12Z UPPER AIR ANALYSIS INDICATES UPPER LOW CENTERED ON
THE WY/CO BORDER...WITH ELONGATED 500MB HEIGHT FALLS THROUGH CO/NM.
UPPER-LEVEL JET STREAK HAD ROUNDED THE BASE OF THE LOW AND ALSO HAD
WEAKENED...WITH SPEEDS UP TO 95KT IN AZ/NM. 850MB LOW WAS CENTERED
IN EASTERN CO...WITH WARM FRONT EXTENDING ALONG THE KS-NEB BORDER
AND DRYLINE FROM NORTH CENTRAL KS THROUGH WESTERN OK/CENTRAL TX.
AHEAD OF THE DRYLINE AND WARM FRONT...8C+ MOISTURE PLUME EXTENDED
ACROSS EASTERN NEB/CENTRAL-EASTERN KS/OK...WITH UP TO 45KT
SOUTHWESTERLY LOW-LEVEL JET. 700-500MB LAPSE RATES OF 20C+ EXTENDED
THROUGH KS/OK INTO CENTRAL NEB AND CENTRAL MO...WITH LOWER LAPSE
RATES IN EASTERN NEB/EASTERN KS IN AREA AFFECTED BY MORNING
CONVECTION. AT 18Z...SURFACE LOW WAS CENTERED IN CENTRAL NEB...WITH
OUTFLOW BOUNDARY EXTENDING FROM N OF KSLN TO NEAR KEMP...AND LIKELY
SYNOPTIC WARM FRONT EVIDENT FROM NEAR KCNK TO NEAR KMYZ TO NORTH OF
KFNB TO NEAR KICL.
MAIN FORECAST CONCERN IS CONVECTIVE POTENTIAL THROUGH THIS
EVENING...AND AGAIN TOMORROW. MORNING CONVECTION IN SOUTHEAST
NEB/EASTERN KS/WESTERN MO THREW AN OUTFLOW BOUNDARY DOWN THAT
SUPPRESSED THE WARM SECTOR SOUTHWARD INTO KS. SOME RECOVERY HAS
OCCURRED THROUGH THE DAY...WITH GHOST OF A SYNOPTIC WARM FRONT INTO
SOUTHEAST NEB...THOUGH RAP ANALYSIS INDICATES CAP IS STILL IN PLACE
AND UNCAPPED WARM SECTOR IS STILL IN CENTRAL KS. WITH A COUPLE MORE
HOURS OF HEATING AND RECOVERY...IT REMAINS POSSIBLE FOR THAT WARM
SECTOR TO RECOVER IN OUR FAR SOUTHERN COUNTIES IN NEB...ALONG AND
SOUTH OF THE SYNOPTIC WARM FRONT...WHICH WOULD RAISE THE POTENTIAL
FOR SURFACE-BASED CONVECTION AND ALL ATTENDANT THREATS. NORTH OF
THE WARM FRONT...POTENTIAL STILL EXISTS FOR HAILERS THROUGH THE
EVENING AS CONVECTION GETS GOING. THREAT FOR TORNADOES IS
CONDITIONAL ON DESTABILIZATION...BUT HIGH ENOUGH TO BE INCLUDED IN A
TORNADO WATCH FOR A FEW COUNTIES IN SOUTHEASTERN NEB.
SHOWERS AND THUNDERSTORMS WILL GROW UPSCALE THIS EVENING...AND WITH
UPPER-LEVEL LOW IN NO HURRY TO EXIT...MAY REGENERATE AND PERSIST
THROUGH THE NIGHT IN SOME LOCATIONS. HEAVY RAIN WILL REMAIN A
THREAT TONIGHT...WITH PERIODS OF SHOWERS AND THUNDERSTORMS.
UPPER LOW IS PROGGED TO ROTATE INTO CENTRAL NEB ON
WEDNESDAY...DRAWING A WARM SECTOR INTO EASTERN NEBRASKA/WESTERN IA
IN THE AFTERNOON. THOUGH THREATS ARE LOWER ON WEDNESDAY...RISK OF
SURFACE-BASED CONVECTION DOES EXIST...WITH THREATS FOR
HAIL...WIND...AND MAYBE EVEN A TORNADO OR TWO. THREAT IS
CONDITIONAL ON GETTING SOME DESTABILIZATION DURING THE DAY IN BREAKS
BETWEEN ROUNDS OF CONVECTION. RISK OF STORMS SHOULD WANE EARLIER IN
THE EVENING AS COOLER AIR DRAWS DOWN INTO EASTERN NEB/WESTERN IA
BEHIND THE EXITING LOW...BUT CHANCE OF AT LEAST SHOWERS SHOULD
LINGER THROUGH THURSDAY.
A SHORT BREAK IN THE CHANCES FOR PRECIPITATION FINALLY GIVES US A
BREATHER ON THURSDAY NIGHT AS NEXT UPPER LOW DIGS INTO THE WESTERN
US...BUT CHANCES FOR SHOWERS AND PERHAPS A RUMBLE OF THUNDER RETURN
THROUGH THE DAY ON FRIDAY. HAVE LOWERED HIGHS FOR WEDNESDAY THROUGH
FRIDAY UNDER GENERALLY CLOUDY AND MURKY PATTERN.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 243 PM CDT TUE APR 26 2016
RAIN CHANCES RAMP UP QUICKLY FRIDAY NIGHT AND SATURDAY AS THE NEXT
UPPER LOW SLIDES TOWARD THE PLAINS...WITH FAIRLY HIGH CONFIDENCE IN
RAIN BUT LOW CONFIDENCE IN THUNDER. RIGHT NOW...IT LOOKS LIKE
EASTERN NEB/WESTERN IA WILL MOSTLY BE ON THE COOL SIDE OF THE
SURFACE LOW...WITH LOW RISK FOR THUNDER BUT CERTAINLY POTENTIAL FOR
RAIN. LOW WEAKENS AND PULLS AWAY AROUND MONDAY...WITH LITTLE OR NO
CHANCE OF RAIN BY MONDAY/TUESDAY. TEMPERATURES REMAIN ON THE COOLER
SIDE THROUGH THE REST OF THE FORECAST.
&&
.AVIATION...(18Z TAFS FOR KOMA...KLNK...KOFK THROUGH 18Z WEDNESDAY)
ISSUED AT 1230 PM CDT TUE APR 26 2016
GENERALLY VFR WEATHER IS EXPECTED THROUGH THE AFTERNOON UNTIL
THUNDERSTORMS DEVELOP IN KANSAS OR SOUTHEAST NEBRASKA AND MOVE
NORTH. THOSE STORMS WILL LIKELY HIGH KLNK AND KOMA BETWEEN 00Z AND
04Z...WITH ANOTHER ROUND EXPECTED AFTER 06Z. MVFR CIGS WILL
OVERSPREAD ALL OF EASTERN NEBRASKA AFTER 06Z...WITH AN OCCASIONAL
IFR CIG/VSBY IN SHOWERS/THUNDER. KOFK WILL LIKELY REMAIN UNDER
IFR SHOWERS MUCH OF WEDNESDAY MORNING WITH KLNK AND KOMA SEEING
MVFR CIGS BUT A DECREASE IN PRECIPITATION.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MAYES
LONG TERM...MAYES
AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
121 PM CDT TUE APR 26 2016
.UPDATE...
ISSUED AT 719 AM CDT TUE APR 26 2016
THE RAP MODEL IS TRENDING COLDER. THE COLD AIR IS OVER-TAKING THE
FCST AREA AND SNOW IS UNDERWAY ACROSS NORTHWEST NEB IN SIOUX
COUNTY. SNOW MAY BE UNDERWAY IN PARTS OF SHERIDAN COUNTY ALSO. A
NEW FORECAST IS OUT FOR PERIODS OF SNOW AND COOLER TEMPERATURES
TODAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CDT TUE APR 26 2016
TODAY AND TONIGHT...THE SFC FRONT NEAR DODGE CITY AT 06Z LIFTS NORTH
TO NEAR THE KANSAS NEBRASKA BORDER BY 12Z AND REMAINS STATIONARY
TODAY. THE FRONT THEN GETS SWEPT EAST AND SOUTH TONIGHT AS SFC LOW
PRESSURE DEEPENS ACROSS NCNTL KS.
THE RAP MODEL SHOWS 2000 J/KG OF ELEVATED INSTABILITY JUST NORTH OF
THE SFC FRONT AT 12Z WHICH LIFTS NORTH THROUGH THE FCST AREA TODAY.
THIS INSTABILITY SHOULD BE THE CATALYST FOR THUNDERSTORMS CONTAINING
LARGE AND SMALL HAIL. THIS STORM ACTIVITY COULD BE UNDERWAY BY 12Z
ACROSS SWRN NEB. A SECOND AREA OF ELEVATED INSTABILITY SHOULD REFORM
ACROSS SWRN NEB AROUND 21Z WHICH WILL BE THE GENESIS FOR A SECOND
ROUND OF THUNDERSTORMS TONIGHT WHICH SHOULD LAST FOR MANY HOURS
ACROSS THE SANDHILLS AND PRODUCE AN AREAL AVERAGE RAINFALL NEAR 1
INCH. THE THREAT OF HAIL...LARGE AND SMALL...SHOULD CONTINUE
THROUGHOUT THE EVENING.
THE LATEST RAP MODEL PRODUCES HIGHS ONLY IN THE 40S AND 5OS TODAY.
THIS SEVERAL DEGREES COOLER THAN THE DETERMINISTIC MODEL CONSENSUS.
LOWS TONIGHT FALL INTO THE 30S AND 40S. THE NAM SUGGESTS A MIX OF
RAIN AND SNOW ACROSS SHERIDAN COUNTY WHILE THE GFS KEEPS THE PTYPE
ALL RAIN. THE GFS WAS PREFERRED AS THE SNOW AND COLDER AIR APPEARS
ELUSIVE THIS MORNING...CONFINED TO WY...ND AND MT.
THE TORNADO POTENTIAL APPEARS VERY CONDITIONAL THIS AFTERNOON AS THE
MODEL CONSENSUS LIFTS THE SFC LOW AND TRIPLE PT THROUGH KS TODAY AND
TO NEAR LINCOLN NEB BY WEDNESDAY MORNING. THIS WOULD PROBABLY KEEP
ERN LINCOLN COUNTY...FRONTIER AND SRN CUSTER COUNTIES IN THE COOL
SECTOR LESSENING THE RISK OF TORNADO DEVELOPMENT. IF THE WARM FRONT
CAN LIFT INTO SRN NEB...TO NEAR I-80 EAST OF NORTH PLATTE...THEN THE
TORNADO RISK WOULD INCREASE SIGNIFICANTLY.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 325 AM CDT TUE APR 26 2016
BEGINNING 12Z WEDNESDAY. THE NEGATIVELY TILTED UPPER LEVEL LOW IS
PROJECTED TO BE CENTERED NEAR THE KS/NEB BORDER ON WEDNESDAY. THE
PLACEMENT OF THE LOW FAVORS THE HIGHEST POPS ACROSS OUR NORTHERN
ZONES...BUT ALL AREAS HAVE A SHOT AT ADDITIONAL ROUNDS OF
SHOWERS/STORMS. THE LATEST GUIDANCE HAS BACKED OFF ON THE
INSTABILITY PARAMETERS THIS EVENING FOR WEDNESDAY...BUT SUFFICIENT
ELEVATED CAPE REMAINS FOR AT LEAST AN ISO MENTION OF THUNDER FROM
SOUTHWEST NEB NORTHEAST TO OUR NORTH CENTRAL NEB ZONES. AS THE LOW
EJECTS EAST IN THE EVENING HOURS...THE MODELS SUGGEST ENOUGH COLD AIR
ON THE BACKSIDE OF THE LOW FOR A COMPLETE CHANGE OVER TO SNOW ACROSS
NW NEB...AND A MIX AS FAR EAST AS THE HIGHWAY 83 CORRIDOR. THE
RECENT TREND OF THE MODELS HAS BEEN COOLER...WHICH WILL NEED TO BE
MONITORED IN THE EVENT THAT ACCUMULATIONS OCCUR. WARM GROUND
TEMPERATURES WILL CREATE AN UNFAVORABLE ENVIRONMENT FOR
ACCUMULATIONS ACROSS NW NEB...SO FOR NOW...WILL KEEP ACCUMULATIONS
MINIMAL. THE LOW WILL LIFT TOWARD SOUTHERN WISCONSIN ON THURSDAY
ALLOWING A LOW AMPLITUDE RIDGE TO FOLLOW. THE RIDGE WILL BE
CHARACTERIZED AS TRANSIENT AS THE NEXT LOW CLOSES ON THE PLAINS FOR
FRIDAY. TEMPERATURES WITH THE RIDGE WILL HAVE LITTLE TIME TO
RECOVER...SO THE BELOW AVERAGE HIGHS WILL CONTINUE INTO THE NEXT
SYSTEM WITH THE POSSIBILITY OF A MIX OF SNOW ONCE AGAIN ACROSS
NORTHWEST NEBRASKA EARLY FRIDAY MORNING...ELSEWHERE SHOWERS OF RAIN
ARE FORECAST. ONE WOULD EXPECT THE TRACK OF THE H5 LOW WOULD ALLOW
SOME INSTABILITY TO WORK BACK INTO SOUTHERN PORTIONS OF THE CWA AT A
MINIMUM. WILL ONCE AGAIN KEEP AN ISO T MENTION GOING IN THE
FORECAST FRIDAY AFTERNOON INTO EARLY SATURDAY. IT SHOULD BE NOTED
THAT THE ECMWF IS COOLER THAN THE GFS WITH THE WEEKEND SYSTEM...THUS
A MIX OF SNOW IS POSSIBLE ONCE AGAIN ACROSS NW NEBRASKA DURING THE
EARLY MORNING HOURS AS THE ECMWF SUGGESTS H85 T/S FALLING BELOW 0C.
ANOTHER POTENTIALLY SIGNIFICANT TREND IS THAT BOTH THE GFS AND EC
ARE GENERATING MODERATE QPF AT TIMES OVER MUCH OF THE CWA AS THE
TRACK NOW FAVORS THE SANDHILLS. IN ADDITION...AS THE H5 LOW TAKES
ON A NEGATIVE TILT OVER THE HIGH PLAINS...IT STALLS AND IMPACTS THE
CWA FOR A PERIOD OF 48 HOURS OR MORE. SOLID RAIN CHANCES WILL
CONTINUE INTO MONDAY OF NEXT WEEK WITH THE POSSIBILITY OF A MIX OF
RAIN AND SNOW ACROSS THE NORTHWEST DURING THE EARLY MORNING HOURS.
TEMPERATURES WILL BE COOL THROUGH MUCH OF THE EXTENDED GIVEN THE
PRESENCE OF CLOUDS...PRECIP AND PERIODS OF CAA. BY EARLY NEXT WEEK A
WELL DEFINED RIDGE IS SHOWN TO DEVELOP AND SPREAD WARMING TEMPS BACK
ACROSS THE CWA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1251 PM CDT TUE APR 26 2016
A WARM FRONT WILL REMAIN SOUTH OF THE AREA THROUGH TONIGHT...WITH
PERSISTENT AND WIDESPREAD MVFR AND LOCAL IFR CEILINGS ACROSS ALL
OF WESTERN AND NORTH CENTRAL NEBRASKA TO THE NORTH OF THE FRONT.
AREAS OF SHOWERS AND TSTMS CAN ALSO BE EXPECTED THROUGH WEDNESDAY
MORNING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CDC
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...TAYLOR
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1246 PM CDT TUE APR 26 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 321 AM CDT TUE APR 26 2016
SATELLITE AND OBSERVATIONS SHOW SOME STRATUS SPREADING ACROSS THE
FORECAST AREA THIS MORNING. RADAR HAS A SINGLE CELL IN NORTH CENTRAL
KANSAS AND MAYBE A FEW SPRINKLES ACROSS SOUTHWEST NEBRASKA.
STILL A LOT OF DIFFERENCES IN THE MODELS THIS MORNING CONSIDERING
THAT THE MAIN EVENT IS LESS THAN 24 HOURS OUT. NEARLY ALL OF THE
MODELS HAVE THERE BEING PRECIPITATION ACROSS THE ENTIRE FORECAST
AREA THROUGH MUCH OF THE PERIOD. THE DETAILS ARE THE PART THAT
CREATE THE CHALLENGE. THE UPPER LOW IS TO THE WEST OF THE FORECAST
AREA AND THE FIRST WAVE OF ENERGY FROM THE LOW IS MOVING INTO THE
AREA EARLY THIS MORNING. THE SURFACE LOW IS STILL TO THE
WEST/SOUTHWEST OF THE FORECAST AREA THIS MORNING AND THERE IS A WARM
FRONT THAT EXTENDS TO THE EAST OF THE FRONT ACROSS NORTHERN KANSAS.
THE CURRENT CONVECTION IS TO THE NORTH OF THE FRONT IN AN AREA OF
WARM MOIST ADVECTION. THE INCREASE OF LOW LEVEL MOISTURE HAS THE
POTENTIAL TO BRING SOME FOG AND MAYBE SOME DRIZZLE TO THE AREA. THE
MAIN AREA WOULD BE TO THE NORTH OF THE FRONT. FOR NOW HAVE SOME
AREAS OF DRIZZLE AND PATCHY FOG.
WITH THE START OF THE CONVECTION ALREADY IN NORTH CENTRAL KANSAS
THERE IS ALREADY SIGNIFICANT CAPE AND SHEAR AND THUNDERSTORMS THIS
MORNING WOULD LIKELY BE SEVERE. THIS ACTIVITY SHOULD BE DECREASING
AROUND SUNRISE AS IT MOVES TO THE EAST.
ONE OF THE MAIN VARIABLES FOR TODAY AND TONIGHT IS THE LOCATION OF
THE SURFACE LOW AND WARM FRONT. SOME OF THE MODELS PUSH THE WARM
FRONT TO THE NORTH...WHILE OTHERS KEEP IT FURTHER TO THE SOUTH. HAVE
KEPT WITH THE FURTHER SOUTH THEORY SINCE THERE COULD BE STRATUS
AROUND THIS MORNING AND INTO THE EARLY AFTERNOON THAT WOULD SLOW THE
FRONT MOVING TO THE NORTH. MOST OF THE MODELS ALSO KEEP THE SURFACE
LOW NEAR THE KANSAS/NEBRASKA BORDER THROUGH THE DAY.
THE NEXT QUESTION WILL BE HOW MUCH PRECIPITATION WILL THERE BE MID
MORNING TO MID AFTERNOON. THE NAM...GFS...ECMWF AND A FEW OF THE
SHORT TERM MODELS HAVE CONVECTION SPREADING ACROSS THE FORECAST AREA
DURING THE MORNING HOURS. ON THE OTHER HAND THE HRRR AND SOME OF THE
OTHER SHORT TERM MODELS HAVE A DRY OR NEARLY DRY PERIOD FOR MID DAY.
HAVE KEPT THE POPS DURING THE DAY...BUT HAVE A FEW CONCERNS HOW MUCH
THERE WILL BE.
WHEN WILL CONVECTION GET GOING THIS AFTERNOON? MOST OF THE MODELS
HAVE CONVECTION STARTING SOMETIME AROUND 21 TO 00Z THIS AFTERNOON
AND CONTINUING THROUGH THE NIGHT. THE BEST CHANCES WILL BE DURING
THE EVENING HOURS. ANOTHER CONCERN IS THAT SOME OF THE MODELS ARE
BRINGING IN A DRY SLOT INTO THE SOUTHERN PORTION OF THE FORECAST
AREA. WILL HAVE TO WATCH THIS TO SEE JUST WHERE AND HOW FAR IT MOVES
INTO THE AREA LATE TONIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 321 AM CDT TUE APR 26 2016
IT IS NO QUESTION THAT THE MAIN CONCERNS LIE WITHIN THE SHORT-
TERM...BUT THE MID AND EXTENDED ARE STILL ACTIVE AND INTERESTING
IN THEIR OWN RIGHT.
MID-TERM (WEDNESDAY - THURSDAY):
THE MAIN FOCUS IN THIS PERIOD IS THE EXIT OF THE UPPER LEVEL LOW
THAT BEGINS TO IMPACT US TODAY. ONCE THE UPPER DISTURBANCE ROTATES
FROM THE SOUTHWEST INTO NEBRASKA EARLY WEDNESDAY MORNING IT
BECOMES RELATIVELY STAGNANT AND SLOW MOVING. THIS CAUSED THE
MULTIPLE PV ANOMALIES ROTATING AROUND THE UPPER LOW TO CAUSE
CHANCES FOR RAIN THROUGHOUT WEDNESDAY. THINK THE BEST CHANCES WILL
BE OVER SOUTH CENTRAL NEBRASKA ALONG AND NORTH OF WHERE THE
SURFACE LOW TRACKS. THERE ARE SOME DISCREPANCIES ON HOW THE
QUICKLY THE UPPER LOW EJECTS EASTWARD WITH THE GFS AND EC MORE
PROGRESSIVE WHILE THE NAM ROTATES THE ENERGY BACK NORTHWARD OVER
THE NORTHERN PLAINS. REGARDLESS THINK PRECIPITATION WILL WANE LATE
WEDNESDAY AND THAT THE ARE WILL BE MOSTLY DRY WEDNESDAY OVERNIGHT
INTO THURSDAY MORNING.
THURSDAY IS EXPECTED TO BE DRY...BUT THE ACTIVE PATTERN CONTINUES
AS THE NEXT DISTURBANCE APPROACHES FROM THE WEST THURSDAY NIGHT.
IN THE WARM SECTOR AHEAD OF THE NEXT WAVE PRECIPITATION IS
EXPECTED TO DEVELOP FROM SOUTHWEST MOVING TO THE NORTHEAST.
LONG-TERM (FRIDAY - MONDAY):
THIS PERIOD IS LIKELY TO BE WET AT LEAST OFF AND ON. THE UPPER LOW
WILL PROGRESS EASTWARD SLOWLY WHILE THE SURFACE LOW TRACKS
NORTHEAST ACROSS THE AREA AS WELL. PRECIPITATION POTENTIAL IS
FAIRLY HIGH. WATER COULD BE COME A CONCERN. WATCH THIS PERIOD AS
IT NEARS.
THE MAJORITY OF THE FORECAST WAS FOCUSED ON THE SHORT AND MID-TERM
WITH ONGOING CONVECTION...THE LONG-TERM FORECAST IS ABBREVIATED
BECAUSE OF THIS.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1239 PM CDT TUE APR 26 2016
DETERIORATING CONDITIONS ARE EXPECTED AT BOTH TERMINALS LATE THIS
AFTERNOON AS CLOUD COVER CONTINUES TO THICKEN AND LOWER ACROSS THE
LOCAL AREA. EXPECT A FAIRLY TIGHT PRESSURE GRADIENT IN PLACE NORTH
OF THE WARM FRONT...CURRENTLY ACROSS NORTH CENTRAL KANSAS...TO RESULT
IN CONTINUED GUSTY NORTHEASTERLY WINDS OVER THE NEXT FEW
HOURS...BEFORE THEY SUBSIDE A BIT AS THE AFOREMENTIONED WARM FRONT
BEGINS TO LIFT A BIT FURTHER NORTH AND THE GRADIENT WEAKENS.
AT THE SAME TIME...EXPECT SHRA AND TSRA DEVELOPMENT...SOME OF
WHICH WILL BE SEVERE...TO INITIATE ALONG THE WARM FRONT AND
PROPAGATE NORTHWARD DURING THE EVENING HOURS. AS THE SURFACE LOW
FOLLOWS SUIT AND LIFTS INTO SOUTHEASTERN NEBRASKA BY EARLY
WEDNESDAY MORNING...EXPECTED CONTINUED SHOWER AND THUNDERSTORM
DEVELOPMENT ACROSS THE LOCAL AREA WITH STRONG NORTHERLY WINDS ON
THE BACKSIDE OF THE SURFACE LOW. OVERALL...THE BEST CONDITIONS
WILL BE OVER THE NEXT COUPLE OF HOURS...WITH MVFR CIGS/VSBYS
BECOMING WIDESPREAD THIS EVENING...WITH TEMPORARY LIFR CONDITIONS
POSSIBLE IN +TSRAS AND ON THE BACKSIDE OF THE SURFACE LOW TOMORROW
WHEN PREVAILING CIGS WILL DROP BELOW 500FT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...JCB
LONG TERM...BILLINGS WRIGHT
AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
154 PM EDT TUE APR 26 2016
.SYNOPSIS...
WARM WEATHER IS EXPECTED THROUGH FRIDAY. A COLD FRONT WILL BRING
SHOWERS THURSDAY INTO THURSDAY NIGHT. HIGH PRESSURE WILL BUILD IN
ON SATURDAY BRINGING A BIT OF A COOL DOWN. RAIN CHANCES RAMP UP
ON SUNDAY AND WILL PERSIST FOR THE FEW DAYS THAT FOLLOW.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM TUESDAY...EXPANSIVE SURFACE HIGH PRESSURE CENTERED
WELL OFF THE MID-ATLANTIC COAST WILL CONTINUE TO RIDGE BACK INTO
THE SOUTHEAST TODAY. THIS HIGH WILL BE THE CONTROLLING INFLUENCE
INTO OUR SENSIBLE WEATHER...KEEPING A SLOW MOVING COLD FRONT
STALLED WELL TO OUR NORTH ACROSS THE OH VLY AND INTO SOUTHERN NEW
ENGLAND.
RETURN FLOW AROUND THIS HIGH COMBINED WITH ZONAL FLOW ALOFT WILL
DRIVE TEMPS TO ABOVE CLIMO VALUES TODAY...WITH MID 80S EXPECTED
INLAND AND UPPER 70S ALONG THE IMMEDIATE COAST. THE COAST WILL BE
MUCH COOLER THANKS TO A STRONG SEA BREEZE FORECAST TO DEVELOP
EARLY THIS AFTERNOON...WITH S/SW WINDS INCREASING TO AROUND 15
MPH. THIS WILL ALSO DRIVE ENOUGH MOISTURE INTO THE COLUMN TO
PRODUCE WIDESPREAD BUT MOSTLY SHALLOW CUMULUS INLAND FROM THE SEA
BREEZE TODAY. LATEST HRRR AND ARW SUGGEST ISOLATED SHOWERS ARE
POSSIBLE...AND HAVE INCREASED POP FROM INHERITED...BUT MAINTAINED
VALUES BELOW MENTIONABLE DUE TO THE DRY AIR ALOFT AND A SUBSIDENCE
INVERSION AROUND 800MB. CANNOT RULE OUT A STRAY SHOWER TODAY BUT
FELT IT MORE ACCURATE TO KEEP POP SILENT ATTM.
A WARM AND HUMID NIGHT FORECAST AS WARM SW FLOW PERSISTS. MINS WILL
DROP ONLY INTO THE LOW AND MID 60S...WARMEST NEAR THE COAST...AND
A STRONG LLJ PREVENTS STEEPENING OF THE NOCTURNAL INVERSION.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM TUESDAY...EVEN THOUGH THE UPPER LEVEL RIDGE ACROSS
THE SE UNITED STATES WILL TECHNICALLY REMAIN IN PLACE WEDNESDAY
AND THURSDAY...IT WILL GET BEATEN DOWN BY SEVERAL SHORTWAVE
DISTURBANCES. SURFACE HIGH PRESSURE WILL REMAIN WELL OFF THE EAST
COAST...FEEDING HEAT AND MOISTURE NORTHWARD FROM FLORIDA.
WITH INLAND HIGHS REACHING THE MID 80S BOTH DAYS...SURFACE-BASED
INSTABILITY SHOULD REACH 1000 J/KG WEDNESDAY AND MAY APPROACH 1500
J/KG ON THURSDAY. THIS SHOULD LEAD TO IMPRESSIVE CUMULUS GROWTH AND
SOME OF THE FIRST AIRMASS THUNDERSTORMS OF THE YEAR. THESE STORMS
SHOULD CONCENTRATE ALONG THE SEABREEZE BOUNDARY BOTH DAYS AND ALSO
AHEAD OF AN UPPER DISTURBANCE MOVING OVERHEAD THURSDAY. FORECAST
POPS ARE AROUND 20 PERCENT WEDNESDAY AND 40 PERCENT ON THURSDAY.
A COLD FRONT DROPPING SOUTH FROM NEW ENGLAND SHOULD MAY MAKE IT AS
FAR SOUTH AS NORTHEASTERN NORTH CAROLINA ON WEDNESDAY. THIS BOUNDARY
WILL REMAIN NEARLY STATIONARY THROUGH THURSDAY...BUT RECENT MODELS
ARE SUGGESTING IT MAY SAG SOUTH INTO SOUTHEASTERN NORTH CAROLINA
THURSDAY NIGHT. SHOULD THIS OCCUR IT COULD LEAD AN ENHANCEMENT IN
SHOWER AND THUNDERSTORM COVERAGE. CONFIDENCE IN THE MOVEMENT OF THIS
BOUNDARY IS LOWER THAN NORMAL GIVEN THAT ITS POSITION WEDNESDAY AND
THURSDAY WILL BE HEAVILY INFLUENCED BY UPSTREAM THUNDERSTORMS ACROSS
VIRGINIA AND NORTHERN NORTH CAROLINA...NONE OF WHICH HAVE DEVELOPED
YET.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 300 AM TUESDAY...COOL FRONT PUSHES THROUGH EARLY FRIDAY AND
TAKES ANY MOISTURE ALONG WITH IT. TEMPERATURES LIKELY TO REMAIN
ABOVE CLIMO THOUGH AS THE MAIN COOL PUSH IS DELAYED UNTIL FRIDAY
NIGHT WITH THE PASSAGE OF A WAVE OFF MID ATLANTIC COAST. THIS
SECONDARY PUSH WILL BRING SEASONABLE TEMPERATURES BACK BY SATURDAY
AS HIGH PRESSURE RIDGES IN FROM THE NORTH. WARM FRONT LIFTS BACK
THROUGH TO THE NORTH ON SUNDAY AND CONSIDERABLE MOISTURE RETURN
APPEARS TO ACCOMPANY AND FOLLOW ITS PASSAGE. FOR THE REMAINDER OF
THE PERIOD THE UPPER RIDGE BREAKS DOWN AND A VERY POSITIVELY
TILTED TROUGH HANGS UP TO OUR WEST. THIS WILL KEEP US IN A VORT-
LADEN SOUTHWESTERLY FLOW ATOP INCREASING GULF MOISTURE FOR SOME
RATHER UNSETTLED WEATHER.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 18Z...EXPECT VFR CONDITIONS THRUOUT THE VALID 24 HR 18Z ISSUANCE
PERIOD. WINDS REMAIN THE PROBLEM CHILD FOR THIS FCST.
LIMITED MOISTURE AND FORCING FROM AN INLAND PROGRESSING AND POTENT
SEA BREEZE THAT WILL YIELD FEW/SCT DIURNALLY DRIVEN CU THRU THIS
AFTN AND EARLY EVENING. BEHIND THE SEA BREEZE...STABLE LOW LEVEL
MARINE AIR WILL KEEP SKIES SKC. SUBSIDENCE ALOFT WILL LIMIT THE
VERTICAL GROWTH OF THE CU...WITH THEIR TOPS BEING FLATTENED OUT.
THUS COULD OBSERVE MODERATE CU GROWTH AT BEST...WITH NO PCPN
EXPECTED. FOR TONIGHT...DIURNALLY DRIVEN CU WILL DISSIPATE THIS
EVENING. DO NOT EXPECT ANY FOG DEVELOPMENT DUE TO SFC WINDS
STAYING ACTIVE.
AS FOR WINDS...THE CENTER OF HIGH PRESSURE WILL PUSH FURTHER
OFFSHORE FROM THE CAROLINA COASTS THRU THIS PERIOD...WITH ITS SFC
RIDGE AXIS EXTENDING WESTWARD AND ONSHORE NEAR THE GA-SC STATE
LINE. A SLOW TIGHTENING OF THE SFC PG WILL ALSO BE PRESENT INTO
WED. IN ADDITION...AN ACTIVE AND POTENT INLAND PROGRESSING SEA
BREEZE THIS AFTN...WILL REACH THE FLO AND LBT LINE AROUND SUNSET.
OVERALL...LOOKING AT SW-WSW WINDS AT 10 KT G15 KT...BACKING TO
S-SSW AT 10-15 KT WITH G17-19 KT. THE COASTAL TERMINALS WILL SEE
S-SSW AROUND 15 KT G20-25 KT INTO THIS EVENING. ALL LOCATIONS WILL
SEE WINDS BACK TO SW-WSW AT 5 TO 10 KT BY MIDNIGHT AND LIKELY HOLD
AT THIS SPEEDS OVERNIGHT. THE LATTER DUE TO A DEVELOPING LOW-LEVEL
JET FROM THE SW AT 30-35 KT AT 1100 TO 1400 FT AGL. AS A RESULT...
COULD SEE WIND GUSTS UP TO 15 KT ESPECIALLY AT THE COASTAL
TERMINALS AFTER MIDNIGHT. THE SFC PG RELAXES-SOME BY WED DAYTIME
MORNING...YIELDING WSW WINDS AT 5 TO 10 KT. THE WED SEA BREEZE
WILL DEVELOP BY NOON.
EXTENDED OUTLOOK...ISOLATED CONVECTION POSSIBLE WED AFTERNOON AND
EVENING. INCREASED CHANCES FOR SCATTERED CONVECTION THURSDAY INTO
FRIDAY DUE TO A BACK-DOOR COLD FRONT DROPPING SOUTHWARD.
OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM TUESDAY...HIGH PRESSURE CENTERED WELL OFF THE COAST
WILL DRIFT SLOWLY MORE TO THE EAST THROUGH TONIGHT. THIS WILL
CONTINUE S/SW WINDS ACROSS THE WATERS...WITH SPEEDS INCREASING TO
AROUND 15 KTS. A STRONG SEA BREEZE CIRCULATION IS FORECAST THIS
AFTN AND EVENING...SO WINDS WITHIN THE NEAR SHORE WATERS MAY BACK
A BIT TO THE SOUTH AND GUST TO 20 KTS AT TIMES...BEFORE THE
SYNOPTIC FLOW AGAIN BECOMES PREDOMINANT TONIGHT. SEAS CURRENTLY
AROUND 2-3 FEET MAY LOCALLY BUILD TO 3-4 FEET IN SPOTS TONIGHT IN
A COMBINATION OF ENE SWELL AND LOCAL SHORT PERIOD WIND CHOP.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM TUESDAY...HIGH PRESSURE WILL REMAIN WELL OFF THE EAST
COAST. A COLD FRONT PUSHING SOUTH FROM NEW ENGLAND WILL MAKE IT AS
FAR SOUTH AS NORTHEASTERN NORTH CAROLINA WEDNESDAY. THE FRONT SHOULD
THEN BECOME NEARLY STATIONARY THROUGH THURSDAY AS WAVES OF LOW
PRESSURE RIPPLE ALONG IT. MODELS ARE BECOMING A LITTLE MORE EMPHATIC
THAT THE FRONT MAY PUSH SOUTH INTO SE NORTH CAROLINA THURSDAY NIGHT.
THE TIMING OF THIS FRONTAL PASSAGE IS VERY UNCERTAIN...PARTICULARLY
SINCE MOST MODELS PAINT MULTIPLE CLUSTERS OF THUNDERSTORMS ALONG THE
FRONT THURSDAY AND THURSDAY NIGHT. OUTSIDE OF THUNDERSTORMS THE
STRONGEST SYNOPTIC WIND SPEEDS ARE EXPECTED BOTH WEDNESDAY AND
THURSDAY AFTERNOONS IN ASSOCIATION WITH THE DAILY SEABREEZE
CIRCULATION.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 300 AM TUESDAY...COLD FRONT COMES THROUGH EARLY FRIDAY
LEAVING MUCH OF THE DAY WITH LIGHT AND VARIABLE WINDS. A SECONDARY
PUSH OF HIGH PRESSURE COMES IN FROM THE NORTH FRIDAY NIGHT INTO
SATURDAY TURNING THE WINDS TO NORTHEAST. THE HIGH REMAINS WELL TO
OUR NORTH ON SATURDAY NIGHT AS IT PROGRESSES EASTWARD. LOCALLY
THIS TURNS THE FLOW TO SOUTHEASTERLY OR EVEN SOUTHERLY. DURING ALL
OF THESE DIRECTIONAL CHANGES WIND SPEEDS WILL BE CAPPED IN THE 10
TO 15 KT RANGE. SO WHILE WAVE PERIODS MAY BE UNPLEASANTLY SHORT
AND CHOPPY THERE WILL NOT BE MUCH OVERALL BUILDING OF DOMINANT
WAVE HEIGHTS.
&&
POTENTIAL FOR LIGHT PATCHY FOG THIS MORNING...BUT CONFIDENCE IS
LOW THUS HAVE NOT INTRODUCED INTO GOING FORECAST. LIGHT WINDS WILL
BECOME SOUTHWESTERLY AND INCREASE TO AOB 10 KTS LATER THIS
MORNING. ANTICIPATE SOUTHERLY FLOW TO INCREASE ALONG THE COAST
THIS AFTERNOON WITH WINDS OF 10 TO 20 KTS. ANY MID TO HIGH CLOUD
DEVELOPMENT TODAY WILL REMAIN FEW/SCT IN NATURE. GUSTS WILL
SUBSIDE THIS EVENING AND SOUTHWESTERLY WINDS AOB 10 KTS WILL
CONTINUE OVERNIGHT.
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...JDW
SHORT TERM...TRA
LONG TERM...MBB
AVIATION...DCH
AREA FORECAST DISCUSSION
NWS NORMAN OK
349 PM CDT TUE APR 26 2016
.DISCUSSION...
THE PRIMARY CONCERN THROUGH THIS EVENING WILL BE SEVERE WEATHER,
WHICH IS CURRENTLY ISOLATED BUT DEVELOPING ACROSS NORTHCENTRAL
OKLAHOMA AS WELL AS JUST SOUTH OF THE RED RIVER IN WESTERN NORTH
TEXAS. AT THE SURFACE, A SHARP DRYLINE HAS CAUGHT UP WITH A COLD
FRONT NEARLY ALONG THE STATE LINES IN WESTERN OKLAHOMA AND THE
TEXAS PANHANDLE. ALOFT, A LARGE SCALE TROUGH DIGGING ACROSS THE
SOUTHWESTERN U.S. INTO THE SOUTHERN HIGH PLAINS, WITH THE LEFT
EXIT QUADRANT OF THE 300 MB JET MAXIMA RIGHT OVER WESTERN NORTH
TEXAS. AHEAD OF THIS SYSTEM, STRONG LOW LEVEL MOISTURE IS IN
PLACE, WITH A VERY UNSTABLE ATMOSPHERE ALOFT. WITH CAPE VALUES IN
THE 3000-4000 J/KG RANGE, THE POTENTIAL EXIST FOR SUPERCELL
THUNDERSTORMS TO FIRE UP. LATEST OUN 18Z SPECIAL SOUNDING STILL
SHOWED A LOW LEVEL INVERSION CAP IN PLACE ABOVE THE BOUNDARY
LAYER. HOWEVER, LOW BASED FORCING ALONG THE DRYLINE/COLD FRONT
ALONG WITH SOME MID LEVEL FORCING ASSOCIATED WITH THE TROUGH
SHOULD BE SUFFICIENT TO BREAK THE CAP, RESULTING IN WIDESPREAD
CONVECTION FOR LATE AFTERNOON INTO THE EVENING HOURS. THE STRONG
CAPE VALUES COULD CERTAINLY RESULT IN LARGE HAIL UP TO BASEBALL
SIZE AND/OR SEVERE WIND GUSTS UNDER THE SUPERCELL STORMS. ALTHOUGH
HAIL WILL BE OUR MOST LIKELY CONCERN, SHEAR VALUES OF 45 TO 50 KTS
IN THE 0-6 KM LAYER COULD CERTAINLY FAVOR A FEW TORNADOS
DEVELOPING WITH THESE STORMS. ALTHOUGH MESOSCALE MODELS ARE NOT IN
FULL AGREEMENT, THE HRRR SEEMS TO HAVE A BETTER HANDLE ON THE
SCENARIO, WITH WIDESPREAD CONVECTION BREAKING OUT ALONG THE
SURFACE BOUNDARIES IN WESTERN OKLAHOMA AND WESTERN NORTH TEXAS
FROM NOW THROUGH THE EARLY EVENING HOURS, THEN CENTRAL OKLAHOMA
FOR THE REMAINDER OF THE EVENING. THESE STORMS WILL BE RATHER
QUICK MOVING, SO HYDROLOGY ISSUES/FLOODING CHANCES WOULD BE LOW.
THE SEVERE THREAT WILL BE RAMPING DOWN TOWARD THE MIDNIGHT HOURS
WITH POPS DECREASING WELL DURING THE EARLY MORNING HOURS OF
WEDNESDAY AS THE COLD FRONT AND DRIER AIR PUSH THROUGH.
FOR THE REMAINDER OF THE SHORT TERM, WEDNESDAY WILL BE SUNNY, WITH
MORE MILDER AND SEASONABLY NORMAL TEMPERATURES ON THE BACK SIDE OF
THE COLD FRONT. HOWEVER, THE COLD FRONT IS EXPECTED TO LIFT BACK
NORTHWARD AS A WARM FRONT, BRINGING MOISTURE BACK INTO THE AREA.
ANOTHER LARGE SCALE SYSTEM COMING FROM THE SOUTHWEST WILL AGAIN
BRING POPS OF TSRA BACK INTO THE FORECAST BEGINNING LATE THURSDAY
NIGHT THROUGH FRIDAY, AND POSSIBLY LINGERING AROUND INTO SATURDAY
ACROSS CENTRAL OKLAHOMA.
IN THE EXTENDED RANGE, BOTH GFS & ECMWF SUGGEST ANOTHER LARGE WAVE
MOVING IN FROM THE WEST, REINTRODUCING LOW TSRA POPS FOR LATE
SUNDAY INTO MONDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 56 77 50 79 / 50 0 0 0
HOBART OK 51 77 49 79 / 30 0 0 0
WICHITA FALLS TX 55 81 53 84 / 40 0 0 10
GAGE OK 48 73 44 73 / 10 0 0 0
PONCA CITY OK 57 74 48 76 / 80 10 0 0
DURANT OK 62 82 56 84 / 80 10 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
11/68
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
346 PM CDT TUE APR 26 2016
.DISCUSSION...
AN ACTIVE WEATHER PERIOD IS ANTICIPATED OVER THE MID SOUTH FOR THE
NEXT 24 TO 36 HOURS. THE FIRST CONCERN WILL BE WITH A MESOSCALE
CONVECTIVE SYSTEM (MCS) MOVING SOUTHEAST FROM MISSOURI THIS
EVENING. THE ENVIRONMENT AHEAD OF THIS SYSTEM IS MOST FAVORABLE
FOR MAINTENANCE OF THIS MCS INTO PORTIONS OF NORTHWEST TENNESSEE
THIS EVENING WHERE STRONG INSTABILITY OVERLAPS THE WEAKEST
CAPPING. LOW LEVEL (0-3KM) CAPE VALUES ARE NEARING 100 J/KG...WITH
SBCAPE BETWEEN 2000-2500 J/KG...MID LEVEL LAPSE RATES AROUND 7.0
C/KM...AND DEEP LAYER EFFECTIVE SHEAR EXPECTED AROUND 30 KTS THIS
EVENING OVER NORTHWEST TENNESSEE. FURTHER SOUTH AND WEST...850-700MB
CAPPING INVERSION APPEARS STRONGER. THEREFORE...STORMS SHOULD
MAINTAIN INTENSITY INTO THIS EVENING ACROSS NORTHWEST TENNESSEE
WHERE A FEW SEVERE STORMS WILL BE POSSIBLE. THE PRIMARY THREATS
THIS EVENING WILL BE DAMAGING WINDS AND LARGE HAIL. STORM COVERAGE
AND INTENSITY SHOULD DIMINISH LATER THIS EVENING WITH SOUTHWARD
EXTENT AS CAPPING OVERWHELMS ANY CONVECTIVE ACTIVITY ATTEMPTING TO
PUSH INTO THE BROAD UPPER RIDGING.
ATTENTION WILL TURN WESTWARD BY LATER TONIGHT AS SEVERE
THUNDERSTORMS OVER THE PLAINS STATES THIS AFTERNOON MOVE EAST AND
BECOME INCREASINGLY LINEAR AFTER MIDNIGHT AS THEY ADVANCE INTO THE
OZARKS. THIS ACTIVITY WILL BE DRIVEN BY A NEGATIVELY TILTED
SHORTWAVE ROTATING AROUND AN UPPER LOW CENTERED OVER THE CENTRAL
ROCKIES. THIS SHORTWAVE SHOULD LIFT NORTHEAST FROM THE SOUTHERN
PLAINS INTO THE MIDDLE MISSISSIPPI VALLEY BY WEDNESDAY MORNING.
THE LINE OF THUNDERSTORMS MOVING ACROSS ARKANSAS LATE TONIGHT MAY
MAINTAIN ITS INTENSITY INTO THE EARLY MORNING HOURS AS IT IMPACTS
AREAS WEST OF THE MISSISSIPPI RIVER BEFORE SUNRISE. LATEST
GUIDANCE SUGGESTS THAT MLCAPE VALUES SHOULD REMAIN GREATER THAN
1000 J/KG...WITH MID LEVEL LAPSE RATES IN EXCESS OF 7.0 C/KM WEST
OF THE MISSISSIPPI RIVER PRIOR TO 12Z WEDNESDAY. IN ADDITION...A
LOW LEVEL JET MAX IN EXCESS OF 40 KTS WILL ROTATE ACROSS THESE
LOCATIONS AFTER MIDNIGHT. A FEW SEVERE STORMS WILL BE POSSIBLE
AFTER MIDNIGHT IN AREAS WEST OF THE MISSISSIPPI RIVER. THE PRIMARY
THREATS WILL BE DAMAGING WINDS AND LARGE HAIL. THIS CONVECTION
SHOULD UNDERGO WEAKENING AS IT MOVES ACROSS THE MISSISSIPPI RIVER
WEDNESDAY MORNING AS THE UPPER SUPPORT WITH THE LEAD SHORTWAVE
LIFTS NORTH.
A SECONDARY SHORTWAVE ROTATING AROUND THE SOUTHERN PERIPHERY OF
THE UPPER LOW WILL MOVE INTO THE MID SOUTH AROUND MIDDAY. LATEST
GLOBAL MODEL SUITES IN ADDITION TO A FEW MEMBERS OF HIGH
RESOLUTION CONVECTION ALLOWING MODELS SUGGEST THAT THE ATMOSPHERE
WILL BE ABLE TO RECOVER TO THE WEST OF THE MORNING CONVECTION WITH
SBCAPES EXCEEDING 2000 J/KG...MID LEVEL LAPSE RATES IN EXCESS OF
7.0 C/KM...AND LI/S BETWEEN -6C AND -10C. IF THE ATMOSPHERE CAN
RECOVER SUFFICIENTLY...THEN FORCING ASSOCIATED WITH THE SECONDARY
MID LEVEL SHORTWAVE WILL FORCE ADDITIONAL THUNDERSTORMS...SOME OF
WHICH WOULD BE SEVERE. THERE STILL IS SOME QUESTIONS REGARDING THE
DEGREE OF INSTABILITY AND AMOUNT OF SURFACE HEATING AHEAD OF THIS
SECONDARY WAVE. AT THIS TIME...IT APPEARS THAT THE ATMOSPHERE WILL
RECOVER AND THE AFTERNOON SEVERE THREAT WILL MATERIALIZE ACROSS
THE REGION. DEEP LAYER SHEAR SHOULD REMAIN STRONG ENOUGH TO
SUPPORT SEVERE WEATHER AS WELL WITH 40 KTS MAINTAINED AROUND 5KFT
THROUGH THE AFTERNOON. WINDS MAY ALSO REMAIN SUFFICIENTLY BACKED
NEAR THE SURFACE TO SUPPORT 0-1KM HELICITY VALUES AROUND 200
M2/S2. ALL SEVERE WEATHER THREATS WILL BE POSSIBLE ON WEDNESDAY
WITH THE POTENTIAL FOR DAMAGING WINDS...LARGE HAIL...AND A FEW
TORNADOES...ESPECIALLY DURING THE AFTERNOON. INSTABILITY LEVELS
ALONG AND WEST OF THE MISSISSIPPI RIVER COULD BE SUFFICIENT FOR A
FEW VERY LARGE HAIL REPORTS. PLAN TO MAINTAIN THESE THREATS IN THE
LATEST HAZARDOUS WEATHER OUTLOOK. THUNDERSTORMS SHOULD EVENTUALLY
WEAKEN LATER WEDNESDAY NIGHT/THURSDAY MORNING AS THEY SAG ACROSS
NORTHEAST MISSISSIPPI.
HIGH PRESSURE WILL BUILD IN LATER THURSDAY AND THURSDAY NIGHT WITH
A RETURN TO DRY WEATHER AND CONTINUED WARM TEMPERATURES.
ANOTHER STRONG STORM SYSTEM WILL APPROACH THE MID SOUTH FROM THE
WEST BY THE WEEKEND WITH ADDITIONAL CHANCES FOR NUMEROUS SHOWERS
AND THUNDERSTORMS BEGINNING LATE FRIDAY AND CONTINUING INTO
SUNDAY. THERE WILL BE ADDITIONAL CHANCES FOR SEVERE THUNDERSTORMS
AS WELL AS HEAVY RAINFALL THROUGH THE WEEKEND FOR A LARGE PORTION
OF THE REGION.
DRY WEATHER AND COOLER TEMPERATURES SHOULD RETURN AGAIN TO THE
FORECAST AREA BY THE BEGINNING OF NEXT WEEK.
JLH
&&
.AVIATION...
18Z TAF SET
CURRENTLY...A MCS IS DEVELOPING ACROSS CENTRAL MO. THE LATEST HRRR
SHOWS THE MCS MOVING INTO THE MIDSOUTH AROUND 00Z. AS A
RESULT...HAVE HAD TO MAKE SOME MAJOR CHANGES TO TAFS. HAVE
INTRODUCED VCTS WORDING AT KJBR BEGINNING AT 2Z WITH A TEMPO
BETWEEN 2Z-6Z FOR TSRAS WITH LOW VSBYS/CIGS. ALSO...THINK WINDS
WILL TURN AROUND TO THE NW THEN TO NE AND EVENTUALLY TO SE BEHIND
THE CONVECTION. SOME GUSTY WINDS COULD OCCUR INITIALLY. BEST
TIMING FOR KMKL WILL BE BETWEEN 3Z-7Z WHILE FOR KMEM IT WILL BE
BETWEEN 4Z-7Z. DO NOT THINK THE CONVECTION WILL MAKE INTO INTO
KTUP AS THE RIDGE WILL BE THE STRONGEST OVER NE MS.
ALTHOUGH...BLOWOFF FROM THE CONVECTION WILL COVER THE AREA. AFTER
7Z...CONFIDENCE DWINDLES DRASTICALLY AS ATMOSPHERE MAY BE WORKED
OVER. ALSO...UNSURE IF THERE WILL BE A LINE OF CONVECTION MOVING
FROM THE WEST AS PREVIOUS FORECAST INDICATED. LATEST HRRR SHOWS
THE LINE FALLING APART POSSIBLY BECAUSE IT IS MOVING INTO A MORE
STABLE AIRMASS. WINDS SHOULD EVENTUALLY GO BACK TO THE SOUTH AND
INCREASE IN SPEED.
KRM
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
326 PM CDT TUE APR 26 2016
.DISCUSSION...
QUIET DAY SO FAR ACROSS THE MID STATE WITH TEMPERATURES MAINLY IN
THE LOW TO MID 80S. LARGE UPPER TROUGH THAT WILL BRING SEVERE
WEATHER TO THE GREAT PLAINS HAS A SUBTLE SHORTWAVE OUT EAST OVER
THE MS RIVER VALLEY ALONG WITH A SURFACE STATIONARY/WARM FRONT
EXTENDING NORTH OF THE OH RIVER VALLEY. THIS LOOKS TO HAVE HELPED
GENERATE A STRONG MCS ACROSS MO AND SOUTHERN IL DURING THE
AFTERNOON...AND SOME OF THAT CONVECTION LOOKS TO EVENTUALLY MAKE
ITS WAY INTO THE MID STATE TONIGHT. THE HRRR AND WRF HAVE DECENT
QPF OVER THE REGION BETWEEN 03Z AND 06Z THIS EVENING...SO UPPED
POPS A BIT FOR THE EVENING FOR SOME QUICK MOVING CONVECTIVE
POTENTIAL.
MODELS HAVE BEEN TRENDING BACK A BIT ON PRECIP CHANCES OVERNIGHT
AND INTO THE MORNING WEDNESDAY...SO BACKED OFF A BIT DURING THAT
TIME. KEPT THE AFTERNOON AND EVENING ON WEDNESDAY BASICALLY THE
SAME AS THE PREVIOUS FORECAST SINCE THE MODELS HAVE BEEN
CONSISTENT WITH PRECIP TIMING. IT STILL LOOKS LIKE THE MAIN BAND
OF PRECIP WILL BE OVER THE AREA BETWEEN 00Z AND 06Z...WITH SOME
BETTER CHANCES FOR CONVECTION WEST OF I65 DURING THE LATE
AFTERNOON AFTER 21Z. THE GFS IS THE FASTEST WITH HIGHER PRECIP
POTENTIAL...BUT SHORT TERM MODELS CATCH UP BY 03Z. FOR THE MOST
PART...I65 AND WEST WILL SEE THE MOST PRECIP BEFORE 03Z...AND EAST
WILL SEE HIGHER PRECIP AFTER 03Z.
LOOKING AT SEVERE POTENTIAL FOR TOMORROW...THE SPC HAS THE SLIGHT
RISK MAINLY ALONG THE TN RIVER VALLEY...WITH A MARGINAL
ELSEWHERE. THIS IS LARGELY DUE TO THE DIURNAL SUPPORT LACKING AS
THE CONVECTION MOVES EAST. LOOKING AT MODEL SOUNDINGS...MUCAPE
VALUES ARE DECENT AT AROUND 1500-1700 J/KG ON AVERAGE. 0-6KM
SHEAR IS A BIT WEAKER THAN WHAT WE HAVE SEEN AT AROUND 40 KNOTS.
LONG STORY SHORT THE LOW LEVEL DYNAMICS ARE ON THE WEAKER
SIDE...BUT THE POTENTIAL EXISTS FOR SOME DAMAGING WIND GUSTS AND
HAIL WITH SOME EARLY STRONGER CELLS. IF STORMS GET TO THE AREA
EARLIER...POTENTIAL WILL BE A BIT BETTER AS THE INSTABILITY AND
LOW LEVEL LAPSE RATES WILL SUPPORT STRONGER STORMS. 0-6KM SHEAR
LOOKS TO PEAK AROUND 00Z...AND COMBINED WITH THE BETTER LAPSE
RATES...HAIL AND DAMAGING WINDS WILL BE MORE LIKELY SHOULD STORMS
MOVE IN DURING THE AFTERNOON AND EARLY EVENING.
SHOWERS AND THUNDERSTORMS LOOK TO LINGER INTO THE EARLY PART OF
THURSDAY AS THE UPPER LOW TRACKS TOWARDS THE GREAT LAKES REGION.
DURING THE AFTERNOON THURSDAY MOST OF THE PRECIP CHANCES WILL BE
CONFINED TO THE PLATEAU REGION. SHORTWAVE RIDGING WILL KEEP
THURSDAY NIGHT AND DURING THE DAY FRIDAY DRY ACROSS THE MID STATE.
A SHORTWAVE TROUGH AHEAD OF A LARGER UPPER TROUGH OVER THE THE
PLAINS WILL BRING CHANCES FOR SHOWERS AND THUNDERSTORMS FRIDAY
NIGHT AND INTO THE DAY SATURDAY. BOTH THE GFS AND THE ECMWF HAVE
THE CLOSED UPPER LOW SPIN FOR A BIT OVER THE PLAINS AND EJECT
SHORTWAVES OVER THE REGION THROUGH THE WEEKEND WHICH WILL KEEP
CHANCES FOR SHOWERS AND THUNDERSTORMS IN THE FORECAST. CURRENTLY
SATURDAY NIGHT LOOKS LIKE THE BETTER CHANCE FOR STRONGER STORMS
DURING THE WEEKEND...BUT ITS STILL TOO FAR OUT TO CALL. AS THE
UPPER TROUGH MOVES EAST ACROSS THE EASTERN CONUS...IT LOOKS TO
KEEP PRECIP CHANCES INTO NEXT WEEK.
&&
.AVIATION...
18Z TAF DISCUSSION.
MOSTLY VFR CONDITIONS FOR THIS TAF CYCLE HOWEVER THIS EVENING...
SHOWERS AND THUNDERSTORMS ARE LIKELY TO MOVE INTO THE MID-STATE...
JUST AFTER 00Z FOR KCKV AND AN HOUR OR TWO LATER FOR KBNA. THIS
WILL DROP VIS/CIG TO MVFR/IFR FOR A SHORT PERIOD THEN JUST MVFR
FOR A COUPLE OF HOURS AS LIGHT RAIN PERSISTS BEHIND THE LINE. KCSV
IS A LITTLE TRICKIER AS THE LINE WON`T LIKELY BE AS INTENSE FOR
THEIR TERMINAL. WILL COVER WITH JUST SOME LIGHT RAIN AND MVFR
CIGS. WINDS WILL BE GUSTY AND LIKELY NWLY WITH THE TS THIS EVENING
OTHERWISE RELATIVELY WEAK AND SWLY.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 65 84 64 84 58 / 50 50 60 20 10
CLARKSVILLE 64 80 62 81 57 / 70 60 60 10 10
CROSSVILLE 62 79 63 78 58 / 40 50 70 40 10
COLUMBIA 64 83 63 82 57 / 40 50 60 20 10
LAWRENCEBURG 63 83 63 82 58 / 40 50 60 30 10
WAVERLY 63 81 62 82 57 / 70 60 60 10 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION......BARNWELL
AVIATION........UNGER
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1220 PM CDT TUE APR 26 2016
.UPDATE... /ISSUED 1100 AM CDT TUE APR 26 2016/
INCREASED POPS ACROSS NORTHERN PORTIONS OF THE MID SOUTH LATE
THIS AFTERNOON INTO THIS EVENING.
&&
.DISCUSSION...
LOW LEVEL MOISTURE CONTINUES TO SURGE NORTHWARD INTO THE MID SOUTH
THIS MORNING...ACCOMPANIED BY LOW LEVEL STRATUS DECK ACROSS THE
WESTERN HALF OF THE AREA. THIS LOW LEVEL CLOUD COVER SHOULD MIX
OUT BY LATE MORNING IN MOST AREAS...WHICH WILL ALLOW TEMPERATURES
TO RISE INTO THE LOWER AND MIDDLE 80S BY THIS AFTERNOON ALONG WITH
MIDDLE TO UPPER 60S DEWPOINTS.
REVIEW OF THE 12Z REGIONAL SOUNDING DATA SUGGESTS STRONGER CAPPING
WITHIN THE 850-700 MB LAYER TO THE SOUTHWEST (KLZK...KSHV). THE
CAPPING IS WEAKER TO THE NORTHEAST AS SUGGESTED BY THE 12Z KOHX
SOUNDING. REGIONAL RADAR SHOWS A MESOSCALE CONVECTIVE SYSTEM
(MCS) MOVING THROUGH CENTRAL MISSOURI LATE THIS MORNING AND
PROPAGATING QUICKLY TO THE SOUTHEAST. INSTABILITY ACROSS NORTHERN
PORTIONS OF THE MID SOUTH SHOULD INCREASE SUBSTANTIALLY BY THIS
AFTERNOON IN A WEAKLY CAPPED ENVIRONMENT. LATEST MODEL GUIDANCE
SUGGESTS SBCAPES RISING BETWEEN 2000-3000 J/KG WITH MID LEVEL
LAPSE RATES BETWEEN 7.5-8.0 C/KM AND LI/S AROUND -8C. AS THE
FORWARD PROPAGATING MCS CONVECTION MOVES INTO NORTHERN AREAS EARLY
THIS EVENING...A FEW STORMS MAY REMAIN SEVERE WITH THE POTENTIAL
FOR DAMAGING WINDS AND LARGE HAIL. CONVECTION SHOULD DIMINISH IN
INTENSITY AND COVERAGE WITH SOUTHWARD EXTENT THROUGH THE EVENING
AS MID LEVEL CAPPING NEGATIVELY INFLUENCES CONVECTION. PLAN TO
INCLUDE SLIGHT RISK MENTION FOR SEVERE STORMS ACROSS NORTHERN
AREAS FOR LATE THIS AFTERNOON AND EVENING.
STORMS SHOULD DIMINISH ENTIRELY BY LATE EVENING PRIOR TO REACHING
THE INTERSTATE 40 CORRIDOR.
UPDATED ZONES...GRIDS...AND HAZARDOUS WEATHER OUTLOOK WILL BE SENT
OUT SHORTLY.
JLH
&&
.PREV DISCUSSION... /ISSUED 308 AM CDT TUE APR 26 2016/
SKIES WERE GENERALLY CLEAR ACROSS THE MIDSOUTH WITH PATCHY
STRATOCU IN NORTH CENTRAL ARKANSAS STARTING TO BLEED INTO THE
WESTERN COUNTIES. TEMPERATURES WERE IN THE 60S WITH SOUTH WINDS
RUNNING 5 TO 10 MPH. THOUGH THE MIDSOUTH WAS FREE OF
CONVECTION...STORMS NEAR THE KANSAS CITY METRO ALONG A STATIONARY
FRONT ARE FORMING AHEAD OF SCHEDULE COMPARED TO THE HRRR MODEL.
FOR TODAY AND TOMORROW...BREEZY SOUTH WINDS AHEAD OF A DEVELOPING
STORM IN THE PLAINS WILL CONTINUE TO PUMP GULF MOISTURE INTO THE
MIDSOUTH...WITH DEWPOINTS CLIMBING INTO THE MID AND UPPER 60S BY
THIS AFTERNOON. THIS COUPLED WITH TEMPERATURES IN THE LOW TO MID
80S WILL GENERATE A FAIR AMOUNT OF CUMULUS AND CAPE VALUES NEAR
3000 J/KG. HOWEVER THE CLOSEST TRIGGER TO INITIATE STORMS WILL
LIE WITH HOW THE ABOVE MENTIONED CONVECTION IN MISSOURI UNFOLDS.
HRRR AND NAM MODELS SUGGEST THIS ACTIVITY WILL PROPAGATE EAST
SOUTHEAST ALONG THE FRONT AS IT PUSHES INTO THE LOWER OHIO VALLEY.
A STRONG ENOUGH AND PERSISTENT ENOUGH OUTFLOW FROM THIS MCS COULD
FIRE STORMS LATE THIS AFTERNOON AND EVENING ALONG THE FAR NORTHERN
MIDSOUTH COUNTIES...OF WHICH SOME COULD BE STRONG OR SEVERE GIVEN
THE ANTICIPATED CAPE. FOR NOW WILL PASS THE POTENTIAL ON TO THE
DAYCREW. BETTER CHANCES FOR STORMS WILL ARRIVE LATER TONIGHT AS
CONVECTION MARCHES EAST OUT OF OKLAHOMA AND TEXAS. THIS ACTIVITY
MAY ALSO MAINTAIN A FAIR AMOUNT OF INTENSITY AS IT WILL BE LINKED
TO THE SUPPORTING NEGATIVE TILTED SHORTWAVE. MODELS SHOW THE
LEADING EDGE REACHING THE MISSISSIPPI RIVER NEAR DAYBREAK AND THE
TENNESSEE RIVER BY NOON. AFTER WHICH QUESTIONS ARISE WITH THE
AMOUNT OF LINGERING CLOUD COVER AND THUS THE ABILITY FOR THE
ATMOSPHERE TO SOMEWHAT RELOAD. MODELS SHOW A WEAKER WAVE SWINGING
THROUGH THE OZARKS IN THE 26/0Z TO 26/06Z TIME FRAME THAT MAY BE
ENOUGH FOR AT LEAST ISOLATED STORMS FROM LATE IN THE AFTERNOON
THROUGH THE EVENING. LOW LEVEL SHEAR WILL HAVE WEAKEN ATT...ALONG
WITH RISING HEIGHT FALLS...AS BOTH THE UPPER AND LOW LEVEL SYSTEM
BEGIN FILLING. THE ONLY CAVEAT WILL BE MIDLEVEL LAPSE RATES WILL
FALL TO NEAR 8C...WHICH WOULD LEAD TO A LARGE HAIL THREAT. CHANCES
FOR RAIN WILL DIMINISH FROM WEST TO EAST LATE TOMORROW NIGHT.
HIGHS TODAY WILL BE IN THE LOW TO MID 80S WITH TEMPERATURES
RUNNING ABOUT FIVE DEGREES COOLER TOMORROW. LOWS IN THE 60S.
THURSDAY AND FRIDAY...DRY INITIALLY WITH WEAK LOW LEVEL FLOW AND
A CONTINUANCE OF ABOVE NORMAL TEMPERATURES. A SECOND STORM SYSTEM
WILL DEVELOP IN THE SOUTHERN ROCKIES...SURGING MOISTURE AND
ENERGY BACK INTO THE OZARKS AND LOWER MISSISSIPPI VALLEY BY FRIDAY
AFTERNOON. SHOWERS AND STORMS WILL OVERSPREAD THE AREA FRIDAY NIGHT.
SATURDAY THROUGH MONDAY NIGHT...A GENERALLY WET PERIOD AS THE
UPPER LOW IN THE FOUR CORNERS TAKES A SIMILAR TRACK...AND TIMING
AS THE CURRENT FRONT RANGE LOW. THIS WOULD PLACE THE MAIN JET
CORRIDOR FROM TEXAS TO THE OHIO VALLEY. ROUNDS OF
CONVECTION...WITH SOME STORMS POTENTIALLY SEVERE APPEAR
FAVORABLE...AS WELL AS A THREAT FOR PERIODS OF HEAVIER RAINFALL.
HIGH TEMPERATURES WILL RUN CLOSE TO NORMAL WITH ABOVE NORMAL LOWS.
JAB
&&
.AVIATION...
18Z TAF SET
CURRENTLY...A MCS IS DEVELOPING ACROSS CENTRAL MO. THE LATEST HRRR
SHOWS THE MCS MOVING INTO THE MIDSOUTH AROUND 00Z. AS A
RESULT...HAVE HAD TO MAKE SOME MAJOR CHANGES TO TAFS. HAVE
INTRODUCED VCTS WORDING AT KJBR BEGINNING AT 2Z WITH A TEMPO
BETWEEN 2Z-6Z FOR TSRAS WITH LOW VSBYS/CIGS. ALSO...THINK WINDS
WILL TURN AROUND TO THE NW THEN TO NE AND EVENTUALLY TO SE BEHIND
THE CONVECTION. SOME GUSTY WINDS COULD OCCUR INITIALLY. BEST
TIMING FOR KMKL WILL BE BETWEEN 3Z-7Z WHILE FOR KMEM IT WILL BE
BETWEEN 4Z-7Z. DO NOT THINK THE CONVECTION WILL MAKE INTO INTO
KTUP AS THE RIDGE WILL BE THE STRONGEST OVER NE MS.
ALTHOUGH...BLOWOFF FROM THE CONVECTION WILL COVER THE AREA. AFTER
7Z...CONFIDENCE DWINDLES DRASTICALLY AS ATMOSPHERE MAY BE WORKED
OVER. ALSO...UNSURE IF THERE WILL BE A LINE OF CONVECTION MOVING
FROM THE WEST AS PREVIOUS FORECAST INDICATED. LATEST HRRR SHOWS
THE LINE FALLING APART POSSIBLY BECAUSE IT IS MOVING INTO A MORE
STABLE AIRMASS. WINDS SHOULD EVENTUALLY GO BACK TO THE SOUTH AND
INCREASE IN SPEED.
KRM
&&
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
101 PM CDT TUE APR 26 2016
.AVIATION...
MVFR CIGS ARE QUICKLY ERODING AND ALL TERMINALS WILL BE VFR WITHIN
THE HOUR. EXPECTING SHOWERS AND THUNDERSTORMS TO DEVELOP THIS
EVENING. TIMING IS UNCERTAIN AT THIS TIME. THINK THE BEST CHANCES
WILL BE AFTER ABOUT 03Z...BUT CONVECTION COULD FORM AS EARLY AS
23Z. CONVECTION SHOULD LOWER CATEGORY TO MVFR. AFTER CONVECTION
CLEARS CIGS WILL BE MVFR THROUGH THE NIGHT. SKIES WILL CLEAR
BEHIND A COLD FRONT LATE WEDNESDAY MORNING.
CONVECTION IS UNLIKELY AT DRT AND THEY SHOULD REMAIN VFR THROUGH
THE PERIOD.
&&
.PREV DISCUSSION... /ISSUED 1145 AM CDT TUE APR 26 2016/
DISCUSSION...AIRCRAFT SOUNDING DATA FROM AUS CONTINUES TO SHOW A
STRONG CAP IN PLACE ABOVE 900MB WITH A WARM NOSE AROUND 22.5 DEG C.
THIS IS PRETTY CLOSE TO THE 12Z FORECAST BUFR SOUNDINGS FROM THE
GFS...WITH THE 12Z NAM12 FORECAST BUFR SOUNDING SLIGHTLY WARMER.
BOTH MODELS INDICATE THE CAP COMPLETELY ERODING BETWEEN 21Z-00Z
(4PM-7PM) AS THE TAIL END OF INITIAL HEIGHT FALLS WITH SHORTWAVE
MOVE ACROSS THE REGION. TEXAS TECH 4KM AND HRRR HI RESOLUTION
MODELS ARE NOT INDICATING MUCH CONVECTIVE INITIALIZATION DURING
THE 21Z-00Z TIME FRAME...AND WAIT MORE ON THE FORCING WITH THE
DRYLINE/FRONT AFTER 06Z (1AM). BUT THE NMM/ARW/NAM12/GFS ARE
SHOWING A POSSIBLE SIGNAL 21Z-03Z (4PM-10PM).
SHOULD CONVECTION INITIATE LATE AFTERNOON AND EVENING ACROSS THE
CENTRAL CWA AND I-35 CORRIDOR...FORECAST SOUNDING CAPE VALUES ARE
RATHER IMPRESSIVE THROUGH THIS AREA...AROUND 4000-4500 J/KG...WITH
POSSIBLY A FEW POCKETS EVEN HIGHER. EFFECTIVE DEEP LAYER SHEAR
VALUES OF NEAR 50 KTS COMBINED WITH THE LARGE CAPE VALUES WILL
EASILY SUPPORT SEVERE STORMS CAPABLE OF PRODUCING LARGE HAIL.
IN ADDITION...A SECONDARY DOWNBURST THREAT PRODUCING DAMAGING
WIND GUSTS WILL BE POSSIBLE WITH LARGE DCAPE VALUES. THE OVERALL
TORNADO THREAT IS LOW THIS FAR SOUTH...ALTHOUGH AN ISOLATED
TORNADO CAN NOT BE COMPLETELY RULED OUT. THE MAIN THREAT WILL
CONTINUE TO BE ADVERTISED AS LARGE HAIL...UP TO BASEBALL SIZED.
THE THREAT FOR HAIL AND DAMAGING STRAIGHT LINE WIND GUSTS WILL
DEVELOP INTO THE HILL COUNTRY AFTER MIDNIGHT AS POSSIBLE BROKEN
LINE OF CONVECTION DEVELOPS SOUTH ALONG THE SURGING DRY LINE/FRONT.
MODELS STILL SHOW POCKET OF CAPE 3500-4000 J/KG POOLED RIGHT AHEAD
OF THE BOUNDARY...SO A LARGE HAIL THREAT WILL EXIST ALSO THROUGH
THE HILL COUNTRY. UNCLEAR HOW FAR SOUTH THROUGH THE I-35 CORRIDOR
THE BROKEN LINE UNZIPS OVERNIGHT...BUT COULD BE AS FAR SOUTH AS
SAN ANTONIO.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 66 90 64 87 71 / 60 10 - 20 40
AUSTIN BERGSTROM INTL AIRPORT 66 89 62 87 70 / 60 10 - 20 40
NEW BRAUNFELS MUNI AIRPORT 65 90 63 87 71 / 60 10 - 20 40
BURNET MUNI AIRPORT 61 89 61 86 68 / 60 10 - 20 40
DEL RIO INTL AIRPORT 61 91 63 92 71 / 10 0 0 10 30
GEORGETOWN MUNI AIRPORT 63 89 62 86 70 / 60 10 - 20 40
HONDO MUNI AIRPORT 62 91 61 90 71 / 50 - - 20 30
SAN MARCOS MUNI AIRPORT 65 89 62 87 71 / 60 10 - 20 40
LA GRANGE - FAYETTE REGIONAL 69 88 66 87 72 / 60 30 - 20 30
SAN ANTONIO INTL AIRPORT 65 91 64 88 72 / 60 10 - 20 30
STINSON MUNI AIRPORT 66 91 65 90 73 / 60 10 - 20 30
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...05
SYNOPTIC/GRIDS...RUNYEN
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
1229 PM CDT TUE APR 26 2016
.DISCUSSION...SEE AVIATION DISCUSSION BELOW FOR THE 18Z TAFS.
&&
.AVIATION...A PERSISTENT CLOUD DECK AND PATCHY HAZE/FOG ARE
CREATING MVFR CONDITIONS THIS MORNING...HOWEVER CONDITIONS ARE
EXPECTED TO IMPROVE TO VFR OVER THE NEXT COUPLE OF HOURS. THERE IS
A SLIGHT CHC OF STORMS ACROSS THE BRUSH COUNTRY AND INTERIOR
COASTAL BEND THIS AFTERNOON...THEREFORE KEPT VCTS FOR ALI TAF.
LATE TONIGHT TSRA CHCS INCREASE ACROSS THE NE CWA THUS KEPT THE
PROB30 FOR VCT LATE TONIGHT/EARLY WED MORNING. SFC WINDS ARE
EXPECTED TO BECOME GUSTY THIS AFTERNOON...ESPECIALLY FOR
CRP...THEN DIMINISH TONIGHT. WINDS FOR LRD ARE EXPECTED TO GO MORE
W THIS AFTERNOON AS A DRYLINE SHIFTS E...THEN BECOMES SE ONCE
AGAIN THIS EVENING...BEFORE SHIFTING N TOWARD WED MORNING.
&&
.PREV DISCUSSION... /ISSUED 1026 AM CDT TUE APR 26 2016/
DISCUSSION...THE 12Z CRP SOUNDING WAS A TAD DRIER AND MORE CAPPED
THAN PREVIOUS 24HRS. AM NOT EXPECTING MUCH PRECIP TODAY DUE TO THE
VERY STRONG CAP...HOWEVER THERE IS A SMALL WINDOW ACROSS THE
INLAND PORTIONS OF THE CWA THIS AFTERNOON WHERE CONVECTION COULD
DVLP...AND IF IT DOES...COULD BE SVR DUE TO THE HIGH CAPE VALUES
(3500-4000J/KG) AND UPPER SHORT WAVE. CURRENT FCST HAS THIS
MENTIONED IN THE GRIDS WITH A 20 POP. SFC WINDS ARE ALSO EXPECTED
TO STRENGTHEN THROUGH THE AFTERNOON WITH SCA CONDITIONS
ANTICIPATED ACROSS THE SRN BAYS AND ADJACENT NEARSHORE WATERS.
OVERALL...FCST LOOKS ON TRACK WITH NO MAJOR CHANGES AT THIS TIME.
PREV DISCUSSION... /ISSUED 639 AM CDT TUE APR 26 2016/
DISCUSSION...PLEASE SEE THE AVIATION DISCUSSION BELOW.
AVIATION...MVFR STRATUS WL GRADUALLY LIFT BY NOON TDA ACROSS MOST
OF SOUTH TX. GUSTY SOUTHEAST WINDS UP TO 30 KT WL OCCUR ACROSS
KALI...KCRP AND KVCT DURING THE DAYLIGHT HOURS. ISOLATED SEVERE
STORMS WITH LARGE HAIL WL BE POSSIBLE ACROSS INTERIOR PORTIONS
GENERALLY FROM KALI NORTHWARD BETWEEN 21Z AND 01Z. MVFR STRATUS
WL REDEVELOP QUICKLY AS EARLY AS 23Z AND ENCOMPASS MOST OF THE
AREA BY MIDNIGHT AS MODERATE ONSHORE FLOW PREVAILS. A WEAKENING
LINE OF THUNDERSTORMS WL AFFECT SOUTH TX BY 09Z IN ADVANCE OF A
SOUTHEAST MOVING COLD FRONT. LOCALLY GUSTY WINDS UP TO 40 KT WL BE
THE MAIN CONCERN WITH THESE STORMS ALTHOUGH MOST OF THESE WL BE
WEAKENING DUE TO THE VERY STRONG CAPPING INVERSION IN PLACE.
PREV DISCUSSION... /ISSUED 431 AM CDT TUE APR 26 2016/
SHORT TERM (TODAY THROUGH WEDNESDAY)...ISOLATED CONVECTION WL
ONCE AGAIN BE POSSIBLE ACROSS PORTIONS OF THE BRUSH COUNTRY MAINLY
BETWEEN 21Z AND 01Z TDA. MUCAPES AROUND 4000 J/KG AND 0-6 KM BULK
SHEAR OF 35-40 KTS ALONG WITH A WEAKNESS IN THE CIN WL LINE UP IN
THE VCNTY OF A SFC TROUGH/DRYLINE FEATURE STRETCHING FROM CHOKE
CANYON RESERVOIR TO ALICE. WL MENTION THE POSSIBILITY OF SEVERE
STORMS WITHIN THIS AREA GIVEN THE EXTREME INSTABILITY AND OTHER
FAVORABLE FACTORS MENTIONED. THIS ISOLATED CONVECTION SHOULD
DISSIPATE WELL BEFORE MIDNIGHT GIVEN THE STRENGTHENING CAP. IN
FACT MOST AREAS WL REMAIN DRY TDA GIVEN THE VERY STRONG CAP IN
EXCESS OF 150-200 J/KG.
A LINEAR MCS IS EXPECTED TO ORGANIZE ACROSS CENTRAL AND NORTH TX
TNT IN ADVANCE OF THE APPROACHING MID/UPR CLOSED LOW EMERGING
FROM THE INTERMOUNTAIN WEST INTO THE CENTRAL AND SOUTHERN PLAINS.
THIS MCS WL LKLY AFFECT OUR CWA AFTER MIDNIGHT INTO WED MORNING.
IT IS EXPECTED TO WEAKEN GIVEN THE VERY STRONG CAP AND THE FACT
THAT MOST OF THE MAIN FORCING WL BE PASSING JUST TO OUR NORTH. THE
NERN PORTION OF THE CWA WL STILL WARRANT CHC POPS WITH SLIGHT CHC
POPS MOST EVERYWHERE ELSE. WL STILL MAINTAIN SLIGHT CHC POPS FOR
THE EASTERN AREAS ON WED AFTN AS THE ACTUAL FRONT WL LKLY STALL
ALONG THIS SAME AREA WITH CAPES OF AT LEAST 3000 J/KG.
GENERALLY WENT WITH THE WARMER GUIDANCE AS THIS HAS PERFORMED
BETTER OF LATE ESPECIALLY OUT WEST.
LONG TERM (WEDNESDAY NIGHT THROUGH MONDAY NIGHT)...ACTIVE WEATHER
PATTERN CONTINUES THROUGH THE EXTENDED AS A SERIES OF UPPER LOW`S
CYCLE FROM THE SOUTHERN ROCKIES INTO THE CENTRAL PLAINS.
EXPECT LOW CHC FOR SHOWERS/STORMS ACROSS THE BRUSH COUNTRY THURSDAY
AND AGAIN FRIDAY AFTN AS A SERIES OF WEAK S/W`S EMBEDDED IN THE
SOUTHERN JETSTREAM INTERACT WITH A MOISTENING ENVIRONMENT AND
MODESTLY UNSTABLE ATMOSPHERE. CAPES ARE PROGGED >2500 J/KG AND GFS
FORECAST SOUNDINGS INDICATE THE CAP SHOULD BREAK ALONG THE NWD
RETREATING SFC BOUNDARY. IN ADDITION CYCLOGENESIS IN THE TX
PANHANDLE WILL RESULT IN A STRENGTHENING LOW LVL FLOW ACROSS SOUTH
TEXAS MAKING FOR NEAR BREEZY CONDITIONS WITH SCA`S EXPECTED OVER
THE GULF WATERS FRI-SAT.
A STRONG PACIFIC FRONT WILL MOVE FROM WEST TO EAST ACROSS THE STATE
ON SATURDAY BRINGING A GOOD CHC FOR SHOWERS/STORMS OVER THE
NORTHEAST COASTAL BEND...NEAR THE TAIL END OF A LONG CONVECTIVE
LINE. H85 WINDS TURN SW-WLY IN THE AFTN AS THE BINDERY MOVES
IN...WHICH WILL LIKELY LIMIT THE WWD EXTEND OF CONVECTION ACROSS OUR
CWA.
SUNDAY LOOKS QUIET. THEN ANOTHER POTENT WEATHER SYSTEM MOVES ACROSS
SOUTH TEXAS MONDAY BRINGING A GOOD CHANCE FOR SHOWERS/STORMS. BOTH
THE GFS/EC INDICATE A COLD FRONT WILL MOVE OFF THE COAST MONDAY
NIGHT...WITH COOLER CONDITIONS IN ITS WAKE TUESDAY WITH HIGHS IN THE
70S. UNTIL THEN...TEMPERATURES WILL GENERALLY BE ABOVE NORMAL.
MARINE...ISSUED AN SCA FOR THE SRN BAYS AND NEARSHORE WATERS
FOR MOST OF TDA GIVEN THE TIGHTENING PRESSURE GRADIENT. SCEC
CONDITIONS WL EXIST ELSW. OFFSHORE WATERS WL APPROACH MARGINAL SCA
CONDITIONS TNT. ONSHORE FLOW WL GRADUALLY WEAKEN ON WEDNESDAY AS
THE FRONT STALLS ALONG THE COAST AND WEAKENS THE OVERALL GRADIENT.
ISOLATED TO SCATTERED CONVECTION WL BE POSSIBLE ON WEDNESDAY WITH
THE WEAKENING MCS/OUTFLOW APPROACHING FROM THE NORTH.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 88 74 92 72 86 / 10 20 20 10 20
VICTORIA 86 71 90 69 87 / 10 40 30 10 20
LAREDO 101 71 100 71 97 / 10 10 10 10 20
ALICE 95 72 96 70 90 / 20 20 20 10 30
ROCKPORT 85 74 89 73 83 / 10 20 30 10 20
COTULLA 99 68 95 66 94 / 20 20 10 10 30
KINGSVILLE 92 74 95 72 89 / 10 10 20 10 20
NAVY CORPUS 84 75 87 74 83 / 10 20 20 10 20
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR THE
FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT
ARANSAS...COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS
OUT 20 NM.
&&
$$
TE/81...AVIATION
Area Forecast Discussion
National Weather Service SAN ANGELO TX
1225 PM CDT TUE APR 26 2016
.UPDATE...
Based on analysis of latest short-term models and the latest SPC
Day 1 Outlook, we decided to expand at least 20 PoPs west to
include all our counties. The latest HRRR indicates convection
will begin across our western counties mid afternoon. Also, all
our counties now have severe thunderstorms possible wording for
the remainder of this afternoon.
&&
PREV DISCUSSION... /issued 421 AM CDT TUE APR 26 2016/
SHORT TERM...
(Today and tonight)
.Strong to severe thunderstorms expected today...
A potent shortwave trough is moving east across the Four Corners
early this morning, with strong southwesterly flow aloft
overspreading the southern Plains. Moistening is noted on the
water vapor channel over southeast NM, indicating the arrival of
large scale forcing for ascent. Point soundings indicate that a
cap will persist through early/mid afternoon, but the
aforementioned synoptic scale ascent will erode the cap by 21z.
Isolated to scattered convection is expected to develop east of
the dryline, rapidly intensifying as it moves northeast. The big
question mark is where the dryline will set up this afternoon. The
models have performed poorly the past few days with the low-level
moisture and today will probably be no exception.
The dryline is forecast to be near a San Angelo-Haskell line by
18z, moving a bit farther east (roughly along a line from Fort
McKavett, to Ballinger, to Abilene) by 21z. East of the dryline,
the environment will be conducive to explosive supercell
development. MLCAPE values on the order of 3000-3500 J/kg are
possible with 0-6km shear exceeding 40 kts. Steep mid-level lapse
rates result in big, fat CAPE profiles, supportive of very large
hail. Storms should remain discrete initially, limiting the severe
weather threat in area. In addition, a few tornadoes cannot be
ruled out. However, this potential will likely be limited to the
far eastern zones where LCL heights will be below 1500 meters.
The dryline should begin to retreat around sunset but it is not
expected to move west of the CWA like we have seen previous
evenings. An eastward moving Pacific cold front will overtake the
retreating dryline, shoving low-level moisture and ongoing
convection east toward I-35 after sunset. Thunderstorms may grow
upscale into an MCS as the cold front moves across the CWA this
evening, developing as far west as a San Angelo-Abilene line. The
severe weather threat will persist through the evening hours, with
precipitation tapering off after midnight. Temperatures today will
warm into the mid 80s to near 90 degrees with lows tonight in the
low to mid 50s.
Johnson
LONG TERM...
(Wednesday through Wednesday Night)
Looks like a dry forecast for the first 24 hours of the extended
forecast. The combination of low level dry air and mainly zonal
flow aloft will result in quiet and dry weather. Warm
temperatures are expected with highs in the mid to upper 80s and
overnight lows in the 50s.
(Thursday through Tuesday)
There will a chance of showers and thunderstorms through much of
this time frame. Temperatures will remain warm through this
weekend and finally cooling off by early next week. An upper level
trough over the southwest US at 12Z Thursday will move northeast
across the southern Plains Thursday night and Friday. At the
surface, a warm front will move north across much of West Central
Texas by Thursday evening. Isolated thunderstorms will probably
develop Thursday afternoon and storms will become scattered in
coverage Thursday night across much of the area. The combination
of upper level dynamics and moderate elevated instability may
result in a few severe storms mainly Thursday night. The main
hazards will be large hail and damaging winds. Showers and
thunderstorms continue Friday(have likely Pops over the eastern
1/3 of the area)as a pacific cold front/dryline moves east across
West Central Texas. A few strong to severe storms are possible
over much of area. There will be a chance of showers and storms
over the Northern Edwards Plateau, Northwest Hill Country and
Heartland Friday night as upper level disturbances move northeast
with some elevated instability for assistance. Looks like most of
the weekend will be dry, then the next upper level short wave
trough will move east- northeast across Texas early next week and
a cold front will move south across West Central Texas Sunday
night and Monday morning. As a result, there is another chance of
rain Sunday night through Monday night. Highs will be mainly in
the 80s through this weekend, cooling into the 70s for early next
week.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 55 85 57 88 / 20 5 0 20
San Angelo 52 88 55 90 / 20 5 0 20
Junction 53 88 52 88 / 60 5 0 20
&&
.SJT Watches/Warnings/Advisories...
None.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1145 AM CDT TUE APR 26 2016
.DISCUSSION...AIRCRAFT SOUNDING DATA FROM AUS CONTINUES TO SHOW A
STRONG CAP IN PLACE ABOVE 900MB WITH A WARM NOSE AROUND 22.5 DEG C.
THIS IS PRETTY CLOSE TO THE 12Z FORECAST BUFR SOUNDINGS FROM THE
GFS...WITH THE 12Z NAM12 FORECAST BUFR SOUNDING SLIGHTLY WARMER.
BOTH MODELS INDICATE THE CAP COMPLETELY ERODING BETWEEN 21Z-00Z
(4PM-7PM) AS THE TAIL END OF INITIAL HEIGHT FALLS WITH SHORTWAVE
MOVE ACROSS THE REGION. TEXAS TECH 4KM AND HRRR HI RESOLUTION
MODELS ARE NOT INDICATING MUCH CONVECTIVE INITIALIZATION DURING
THE 21Z-00Z TIME FRAME...AND WAIT MORE ON THE FORCING WITH THE
DRYLINE/FRONT AFTER 06Z (1AM). BUT THE NMM/ARW/NAM12/GFS ARE
SHOWING A POSSIBLE SIGNAL 21Z-03Z (4PM-10PM).
SHOULD CONVECTION INITIATE LATE AFTERNOON AND EVENING ACROSS THE
CENTRAL CWA AND I-35 CORRIDOR...FORECAST SOUNDING CAPE VALUES ARE
RATHER IMPRESSIVE THROUGH THIS AREA...AROUND 4000-4500 J/KG...WITH
POSSIBLY A FEW POCKETS EVEN HIGHER. EFFECTIVE DEEP LAYER SHEAR
VALUES OF NEAR 50 KTS COMBINED WITH THE LARGE CAPE VALUES WILL
EASILY SUPPORT SEVERE STORMS CAPABLE OF PRODUCING LARGE HAIL.
IN ADDITION...A SECONDARY DOWNBURST THREAT PRODUCING DAMAGING
WIND GUSTS WILL BE POSSIBLE WITH LARGE DCAPE VALUES. THE OVERALL
TORNADO THREAT IS LOW THIS FAR SOUTH...ALTHOUGH AN ISOLATED
TORNADO CAN NOT BE COMPLETELY RULED OUT. THE MAIN THREAT WILL
CONTINUE TO BE ADVERTISED AS LARGE HAIL...UP TO BASEBALL SIZED.
THE THREAT FOR HAIL AND DAMAGING STRAIGHT LINE WIND GUSTS WILL
DEVELOP INTO THE HILL COUNTRY AFTER MIDNIGHT AS POSSIBLE BROKEN
LINE OF CONVECTION DEVELOPS SOUTH ALONG THE SURGING DRY LINE/FRONT.
MODELS STILL SHOW POCKET OF CAPE 3500-4000 J/KG POOLED RIGHT AHEAD
OF THE BOUNDARY...SO A LARGE HAIL THREAT WILL EXIST ALSO THROUGH
THE HILL COUNTRY. UNCLEAR HOW FAR SOUTH THROUGH THE I-35 CORRIDOR
THE BROKEN LINE UNZIPS OVERNIGHT...BUT COULD BE AS FAR SOUTH AS
SAN ANTONIO.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 86 66 90 64 87 / 30 60 10 - 20
AUSTIN BERGSTROM INTL AIRPORT 87 66 89 62 87 / 30 60 10 - 20
NEW BRAUNFELS MUNI AIRPORT 87 65 90 63 87 / 20 60 10 - 20
BURNET MUNI AIRPORT 84 61 89 61 86 / 30 60 10 - 20
DEL RIO INTL AIRPORT 92 61 91 63 92 / 10 10 0 0 10
GEORGETOWN MUNI AIRPORT 85 63 89 62 86 / 30 60 10 - 20
HONDO MUNI AIRPORT 89 62 91 61 90 / 20 50 - - 20
SAN MARCOS MUNI AIRPORT 85 65 89 62 87 / 20 60 10 - 20
LA GRANGE - FAYETTE REGIONAL 86 69 88 66 87 / 10 60 30 - 20
SAN ANTONIO INTL AIRPORT 86 65 91 64 88 / 20 60 10 - 20
STINSON MUNI AIRPORT 89 66 91 65 90 / 20 60 10 - 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...05
SYNOPTIC/GRIDS...RUNYEN
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
159 PM EDT TUE APR 26 2016
.SYNOPSIS...
FRONT WITH WAVES OF LOW PRESSURE EXTENDED FROM NEW JERSEY TO
MISSOURI THIS MORNING. THIS FRONT WILL DRIFT SOUTH THEN STALL OVER
THE MID ATLANTIC REGION ON WEDNESDAY. ANOTHER LOW PRESSURE SYSTEM
WILL TRACK FROM THE MID MISSISSIPPI VALLEY TO THE EAST COAST ON
THURSDAY AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1255 PM EDT TUESDAY...
INITIAL BAND OF SHOWERS AND ISOLATED THUNDERSTORMS DISSIPATED
BEFORE REACHING INTO THE NRN PORTION ON OUR FCST AREA...HOWEVER AN
OUTFLOW BOUNDARY IN ITS WAKE OVER CENTRAL WV IS NOW STARTING TO
FIRE...AND NEW RUNS OF HI RES WRF...ESPECIALLY ARW CORE...SEEM TO
HAVE THIS IDEA...ALTHOUGH MAYBE NOT DEVELOPING QUITE FAST ENOUGH.
HRRR ALSO NOT AS QUICK TO DEVELOP THIS...SO BY THE TIME IT DOES
AROUND 20 UTC OR SO IT MAY BE A LITTLE TOO FAR NORTH WITH IT. THIS
ALL MAKES FOR TRICKY TIMING OF WHEN THE BROKEN LINE OF CONVECTION MAY
REACH GREENBRIER COUNTY...BUT WITH MANY MODELS STILL PRETTY SLOW
ON THIS INTO THE EVENING...HAVE MADE SLIGHT ADJUSTMENTS FOR ITS
ARRIVAL AROUND 20 OR 21 UTC...AND THEN NOT TO THE U.S. 460 LINE
UNTIL 00 UTC OR LATER. ALSO LESS AND LESS CHANCE OF MUCH OF
ANYTHING GETTING GOING IN THE MOUNTAINS SOUTH OF THIS GIVEN DRI
AIR ALOFT AND FAIRLY EXTENSIVE CUMULUS FIELD EARLY...SO LOWERED
POPS TO SLIGHT CHC EXCEPT FOR VERY HIGHEST MTNS WITH LOW CHC POP.
SO FAR SFC-BASED CAPE PRETTY LIMITED LARGELY THANKS TO EARLIER
CONVECTION AND RESIDUAL CLOUD COVER AND EARLY START TO CU FIELD.
THIS COULD LIMIT SEVERE POTENTIAL...ALONG WITH LATER ARRIVAL TIME
NOW MAINLY INTO THE EVENING. AN ISOLATED STRONG STORM...PRIMARILY WIND
THREAT...STILL POSSIBLE.
PREV DISCUSSION AS OF 1015 AM EDT TUESDAY...
AREA OF CONVECTION TO THE SOUTH OF THE FRONTAL BOUNDARY CONTINUES
TO DRIFT SOUTHEASTWARD THROUGH NRN WEST VIRGINIA...AND MAY BRUSH
THE FAR NRN PORTION OF OUR FCST AREA BETWEEN 11AM AND NOON BEFORE
DISSIPATING. HOWEVER THIS SHOULD LEAVE AN OUTFLOW BOUNDARY TO AID
IN THE DEVELOPMENT OF MORE CONVECTION BY MID TO LATE AFTERNOON.
FARTHER SOUTH IT LOOKS LIKE SOME WEAK SUBSIDENCE WILL PREVENT MORE
THAN ISOLATED SHWRS OR THUNDERSTORMS TO FORM...AND THESE WOULD BE
CONFINED TO MTNS...BUT BEST CHANCES WILL BE LATE AFTERNOON INTO
EARLY EVENING MAINLY NORTH OF U.S. 460. ONE OR TWO OF THE
CONVECTIVE RESOLVING MODELS DO SUGGESTS A BROKEN LINE WILL MAKE IT
DOWN TO AT LEAST THE NORTH CAROLINA BORDER BY LATE EVENING...BUT
AM SKEPTICAL OF THESE ARE WILL AWAIT 12Z UPDATES TO SOME OF THESE
BEFORE REFINING FORECAST FURTHER. FOR NOW HAVE REDUCED POPS
FARTHER SOUTH AND SLOWED DOWN TIMING OF ARRIVAL OF THES SCATTERED
STORMS. STILL EXPECTING SOME ISOLATED SEVERE THREAT NORTH OF 460
AND MAINLY WEST OF BLUE RIDGE...WITH WIND DAMAGE BEING MOST LIKELY
CONCERN GIVEN DRY AIR ALOFT TO SUPPORT DOWNDRAFTS AND MODEST LOW
LEVEL WIND SHEAR TO ALLOW FOR SOME DEGREE OF ORGANIZATION. CANNOT
RULE OUT A HAIL THREAT BUT INSTABILITY IS NOT ESPECIALLY HIGH AND
WARM BOUNDARY LAYER TEMPS WILL HELP WITH MELTING.
PREV DISCUSSION AS OF 355 AM EDT TUESDAY...
LOW PRESSURE OVER MICHIGAN WILL MOVE EAST ALONG A FRONT INTO
EASTERN PENNSYLVANIA TODAY. THEN THE FRONT WILL MOVE SOUTH INTO
THE MID ATLANTIC REGION LATE TODAY INTO TONIGHT. THE SURFACE
BOUNDARY REACHES THE FORECAST AREA AFTER 00Z/8PM...WHILE THE
850MB FRONT STAYS WELL TO THE NORTH. STARTING OUT WITH LITTLE
CLOUD COVER THIS MORNING SO TEMPERATURES WILL WARM QUICKLY AFTER
SUNRISE. WITH SURFACE DEW POINTS IN THE 50S...CONVECTIVE AVAILABLE
POTENTIAL ENERGY WAS FORECAST TO BE AROUND 1500 J/KG THIS
AFTERNOON AHEAD OF THE FRONT. SOME GUIDANCE SUGGESTED POOLING OF
DEW POINTS IN THE LOWER 60S JUST AHEAD OF THE BOUNDARY WHICH WOULD
RESULT IN EVEN LARGER CAPE. 00Z NAM AS WELL AS THE RAP AND LOCAL
WRF HAVE A BULK OF THE PRECIPITATION THAT WILL BE AHEAD OF THE
FRONT REACHING THE NORTHERN COUNTY WARNING AREA JUST AFTER
18Z/2PM. BETTER COVERAGE OF SHOWERS AND THUNDERSTORMS MAY NOT
PROGRESS SOUTH...REACHING THE VIRGINIA/NORTH CAROLINA BORDER UNTIL
AROUND 00Z/8PM. BETTER VORTICITY ADVECTION AND JET SUPPORT REACH
THE FORECAST AREA TONIGHT SO HAVE INCREASED THE PROBABILITY OF
PRECIPITATION FOR TONIGHT.
GUIDANCE WAS TOO COOL FOR MAXIMUM TEMPERATURES ON MONDAY. HAVE
GONE CLOSER TO WARMER GUIDANCE AND PERSISTENCE FROM MONDAY FOR
MAXIMUM TEMPERATURES TODAY. CLOUDS AND MILD DEW POINTS WILL KEEP
TEMPERATURES FROM DROPPING MUCH OVERNIGHT. HAVE RAISED MINIMUM
TEMPERATURES SLIGHTLY ACROSS THE PIEDMONT TONIGHT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
AS OF 330 AM EDT TUESDAY...
THE UPPER LEVEL PATTERN WILL REMAIN UNSETTLED AS THE WESTERN TROF
SPLINTERS INTO PIECES WITH SEVERAL BITS OF SHORT WAVE ENERGY MOVING IN
OUR DIRECTION INTERSPERSED WITH PERIODS OF GENERALLY FLAT RIDGING. AND
WITHOUT SOLID UPPER LEVEL SUPPORT TO MOVE IT ALONG...THE FRONTAL ZONE
AT THE SURFACE WILL SIMPLY LINGER OVER THE REGION THROUGH THE END OF
THE WEEK. AMPLE CONVERGENCE AND INSTABILITY IN THE FRONTAL ZONE WILL
KEEP UP WITH A CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY. BY FRIDAY
IT APPEARS THAT A SHORT WAVE REMNANT OF THE WESTERN TROF WILL SWING BY
TO OUR NORTH AND HELP PUSH THE FRONTAL BOUNDARY FURTHER TO THE SOUTH
AND ALLOW A WEDGE OF HIGH PRESSURE TO BUILD DOWN EAST OF THE
APPALACHIANS. HOWEVER ANY IMPROVEMENT IN OUR WEATHER LOOK TO BE
MARGINAL SINCE CLOUDS AND SOME LIGHT PRECIPITATION WILL ACCOMPANY THE
WEDGE. TEMPERATURES WILL GENERALLY BE A BIT ABOVE NORMAL THROUGH THE
END OF THE WEEK WITH HIGHS IN THE MID 70S TO AROUND 80 EAST OF THE BLUE
RIDGE...AND IN THE LOW TO MID 70S WEST.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 245 PM EDT MONDAY...
WEAK UPPER RIDGING THROUGH SATURDAY WILL KEEP PRECIP CHANCES CONFINED
TO ISOLATED/WIDELY SCATTERED IN COVERAGE. AT THE SFC...12Z ECMWF KEEPS
WEDGE IN PLACE THROUGH SATURDAY. WHILE TEMPS WERE BROUGHT DOWN A COUPLE
OF DEGREES DURING THIS TIME...THESE FORECAST VALUES STILL MAY BE TOO
WARM.
HOWEVER...BETTER CHANCES FOR MORE WIDESPREAD PRECIPITATION
ARRIVE LATER SUNDAY INTO MONDAY...DEPENDING ON THE ARRIVAL OF AN
OPENING UPPER LOW MOVING THROUGH THE OHIO VALLEY. AS IT TYPICAL
FOR THE LONG RANGE MODELS...THERE IS DISAGREEMENT IN THE TIMING
AND TRACK OF THIS SYSTEM...BUT INDIVIDUAL GEFS ENSEMBLE MEMBERS
SUGGEST THE BEST CHANCES FOR PRECIPITATION WILL BE LATE SUNDAY
INTO EARLY MONDAY...AND THIS IS THE TIME PERIOD WHERE THE POPS ARE
HIGHEST.
TEMPS ARE EXPECTED TO BE BELOW NORMAL EARLY WITH THE WEDGE IN
PLACE TO NEAR NORMAL LATER IN THE LONG TERM PERIOD.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 200 PM EDT TUESDAY...
COLD FRONT REMAINS JUST SOUTH OF THE GREAT LAKES IN NORTHERN OHIO
BUT A BAND OF SHOWERS AND THUNDERSTORMS WELL TO THE SOUTH OF THIS HAS
DEVELOPED ACROSS CENTRAL WEST VIRGINIA...BUT WILL BE SLOW TO MOVE
SOUTHWARD. BEFORE THIS ARRIVES...VFR CONDITIONS WILL PREVAIL...BUT
ANY STORMS COULD PRODUCE BRIEF MVFR CONDITIONS AS WELL AS GUSTY
NORTHWEST WINDS. EXPECTED ARRIVAL TIME AT KLWB AROUND 22
UTC...THEN KBLF...KBCB...KROA...KLYH AROUND 00 UTC PLUS OR MINUS
AN HOUR...THEN LESS CERTAIN THAT THESE WILL EVER GET TO KDAN BUT
LEANING TOWARD THEY EVENTUALLY WILL BUT MORE AROUND 02 UTC AND MAY
NOT EVEN BE THUNDER AT THAT POINT BUT SOME GUSTY NW WINDS STILL
POSSIBLE. LESS LIKELY TO SEE SUB VFR CONDITIONS AT KDAN AS WELL.
THUNDER THREAT WILL DIMINISH BY MIDNIGHT BUT SOME SHOWERS COULD
LINGER...ESPECIALLY AT WESTERN TAF SITES...AND SOME IFR CONDITIONS
MAY EVENTUALLY BE POSSIBLY AT KLWB AND KBLF...ESPECIALLY IF
SHOWERS MOVE AWAY FOR A FEW HOURS. DID NOT INCLUDE ANY PREVAILING
IFR CONDITIONS...BUT MOST CONCERNED ABOUT KLWB LATE TONIGHT. IF
SHOWERS MOVE OUT COULD EASILY GET IFR FOG.
AN UPPER LEVEL WAVE AND MORE ORGANIZED AREA OF THUNDERSTORMS WILL
APPROACH THE WEST BY MORNING AND RECENT GUIDANCE IS SUGGESTING
THAT THIS COULD MAINTAIN THROUGH THE FCST AREA DURING THE MORNING
WEDNESDAY...ALTHOUGH NOT CLIMATOLOGICALLY FAVORED. BEST CHANCES
FOR SHOWERS AND SOME EMBEDDED THUNDERSTORMS WOULD BE IN THE
WEST...AND INCLUDED THOSE WITH MVFR CONDITIONS AT
KBLF...KLWB...AND KBCB...ALTHOUGH NOT ESPECIALLY HIGH CONFIDENCE.
AS FAR AS WINDS...WEST TO SOUTHWEST TODAY...GUSTING TO 15 KTS OR
SO REMAINDER OF AFTERNOON...THEN BECOMING LIGHTER TONIGHT EXCEPT
FRO NEAR ANY STORMS...WHICH COULD BRING THEM TO NORTHWEST OR
NORTH GUSTING BRIEFLY TO 25 OR 30 KTS. MORE VARIABLE
OVERNIGHT...PERHAPS BACK TO WEST. BY EARLY WED BACK DOOR FRONTAL
BOUNDARY MAY ARRIVE AT KLYH FOR A NORTHEAST WIND FOR MUCH OF THE
DAY. THIS MAY NOT GET TO ANY OTHER TAF SITES UNTIL LATE IN DAY OR
OVERNIGHT.
EXTENDED AVIATION DISCUSSION...
THIS BACK DOOR FRONT WILL SLOWLY PUSH THROUGH WEDNESDAY NIGHT AND
THEN REMAIN STALLED OR SLOWLY DRIFT BACK NORTH ON THURSDAY...BEFORE
A STRONGER COLD FRONT ENTERS FROM THE WEST TO PUSH THE WEAKER
FRONT OFFSHORE LATE THURSDAY. DURING THIS TIME...SCATTERED
SHOWERS WITH A FEW AFTERNOON THUNDERSTORMS APPEAR LIKELY. THE
GREATEST CHANCE OF RAIN AND MVFR/IFR CONDITIONS WILL ACCOMPANY THE
STRONGER COLD FRONT ON THURSDAY. SOME CLEARING SHOULD TAKE PLACE
DURING FRIDAY...ALTHOUGH A FEW MOUNTAIN SHOWERS AND MVFR CLOUDS
ARE POSSIBLE.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/SK
SHORT TERM...PH
LONG TERM...PH
AVIATION...AMS/DS/SK
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1258 PM EDT TUE APR 26 2016
.SYNOPSIS...
FRONT WITH WAVES OF LOW PRESSURE EXTENDED FROM NEW JERSEY TO
MISSOURI THIS MORNING. THIS FRONT WILL DRIFT SOUTH THEN STALL OVER
THE MID ATLANTIC REGION ON WEDNESDAY. ANOTHER LOW PRESSURE SYSTEM
WILL TRACK FROM THE MID MISSISSIPPI VALLEY TO THE EAST COAST ON
THURSDAY AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1255 PM EDT TUESDAY...
INITIAL BAND OF SHOWERS AND ISOLATED THUNDERSTORMS DISSIPATED
BEFORE REACHING INTO THE NRN PORTION ON OUR FCST AREA...HOWEVER AN
OUTFLOW BOUNDARY IN ITS WAKE OVER CENTRAL WV IS NOW STARTING TO
FIRE...AND NEW RUNS OF HI RES WRF...ESPECIALLY ARW CORE...SEEM TO
HAVE THIS IDEA...ALTHOUGH MAYBE NOT DEVELOPING QUITE FAST ENOUGH.
HRRR ALSO NOT AS QUICK TO DEVELOP THIS...SO BY THE TIME IT DOES
AROUND 20 UTC OR SO IT MAY BE A LITTLE TOO FAR NORTH WITH IT. THIS
ALL MAKES FOR TRICKY TIMING OF WHEN THE BROKEN LINE OF CONVECTION MAY
REACH GREENBRIER COUNTY...BUT WITH MANY MODELS STILL PRETTY SLOW
ON THIS INTO THE EVENING...HAVE MADE SLIGHT ADJUSTMENTS FOR ITS
ARRIVAL AROUND 20 OR 21 UTC...AND THEN NOT TO THE U.S. 460 LINE
UNTIL 00 UTC OR LATER. ALSO LESS AND LESS CHANCE OF MUCH OF
ANYTHING GETTING GOING IN THE MOUNTAINS SOUTH OF THIS GIVEN DRI
AIR ALOFT AND FAIRLY EXTENSIVE CUMULUS FIELD EARLY...SO LOWERED
POPS TO SLIGHT CHC EXCEPT FOR VERY HIGHEST MTNS WITH LOW CHC POP.
SO FAR SFC-BASED CAPE PRETTY LIMITED LARGELY THANKS TO EARLIER
CONVECTION AND RESIDUAL CLOUD COVER AND EARLY START TO CU FIELD.
THIS COULD LIMIT SEVERE POTENTIAL...ALONG WITH LATER ARRIVAL TIME
NOW MAINLY INTO THE EVENING. AN ISOLATED STRONG STORM...PRIMARILY WIND
THREAT...STILL POSSIBLE.
PREV DISCUSSION AS OF 1015 AM EDT TUESDAY...
AREA OF CONVECTION TO THE SOUTH OF THE FRONTAL BOUNDARY CONTINUES
TO DRIFT SOUTHEASTWARD THROUGH NRN WEST VIRGINIA...AND MAY BRUSH
THE FAR NRN PORTION OF OUR FCST AREA BETWEEN 11AM AND NOON BEFORE
DISSIPATING. HOWEVER THIS SHOULD LEAVE AN OUTFLOW BOUNDARY TO AID
IN THE DEVELOPMENT OF MORE CONVECTION BY MID TO LATE AFTERNOON.
FARTHER SOUTH IT LOOKS LIKE SOME WEAK SUBSIDENCE WILL PREVENT MORE
THAN ISOLATED SHWRS OR THUNDERSTORMS TO FORM...AND THESE WOULD BE
CONFINED TO MTNS...BUT BEST CHANCES WILL BE LATE AFTERNOON INTO
EARLY EVENING MAINLY NORTH OF U.S. 460. ONE OR TWO OF THE
CONVECTIVE RESOLVING MODELS DO SUGGESTS A BROKEN LINE WILL MAKE IT
DOWN TO AT LEAST THE NORTH CAROLINA BORDER BY LATE EVENING...BUT
AM SKEPTICAL OF THESE ARE WILL AWAIT 12Z UPDATES TO SOME OF THESE
BEFORE REFINING FORECAST FURTHER. FOR NOW HAVE REDUCED POPS
FARTHER SOUTH AND SLOWED DOWN TIMING OF ARRIVAL OF THES SCATTERED
STORMS. STILL EXPECTING SOME ISOLATED SEVERE THREAT NORTH OF 460
AND MAINLY WEST OF BLUE RIDGE...WITH WIND DAMAGE BEING MOST LIKELY
CONCERN GIVEN DRY AIR ALOFT TO SUPPORT DOWNDRAFTS AND MODEST LOW
LEVEL WIND SHEAR TO ALLOW FOR SOME DEGREE OF ORGANIZATION. CANNOT
RULE OUT A HAIL THREAT BUT INSTABILITY IS NOT ESPECIALLY HIGH AND
WARM BOUNDARY LAYER TEMPS WILL HELP WITH MELTING.
PREV DISCUSSION AS OF 355 AM EDT TUESDAY...
LOW PRESSURE OVER MICHIGAN WILL MOVE EAST ALONG A FRONT INTO
EASTERN PENNSYLVANIA TODAY. THEN THE FRONT WILL MOVE SOUTH INTO
THE MID ATLANTIC REGION LATE TODAY INTO TONIGHT. THE SURFACE
BOUNDARY REACHES THE FORECAST AREA AFTER 00Z/8PM...WHILE THE
850MB FRONT STAYS WELL TO THE NORTH. STARTING OUT WITH LITTLE
CLOUD COVER THIS MORNING SO TEMPERATURES WILL WARM QUICKLY AFTER
SUNRISE. WITH SURFACE DEW POINTS IN THE 50S...CONVECTIVE AVAILABLE
POTENTIAL ENERGY WAS FORECAST TO BE AROUND 1500 J/KG THIS
AFTERNOON AHEAD OF THE FRONT. SOME GUIDANCE SUGGESTED POOLING OF
DEW POINTS IN THE LOWER 60S JUST AHEAD OF THE BOUNDARY WHICH WOULD
RESULT IN EVEN LARGER CAPE. 00Z NAM AS WELL AS THE RAP AND LOCAL
WRF HAVE A BULK OF THE PRECIPITATION THAT WILL BE AHEAD OF THE
FRONT REACHING THE NORTHERN COUNTY WARNING AREA JUST AFTER
18Z/2PM. BETTER COVERAGE OF SHOWERS AND THUNDERSTORMS MAY NOT
PROGRESS SOUTH...REACHING THE VIRGINIA/NORTH CAROLINA BORDER UNTIL
AROUND 00Z/8PM. BETTER VORTICITY ADVECTION AND JET SUPPORT REACH
THE FORECAST AREA TONIGHT SO HAVE INCREASED THE PROBABILITY OF
PRECIPITATION FOR TONIGHT.
GUIDANCE WAS TOO COOL FOR MAXIMUM TEMPERATURES ON MONDAY. HAVE
GONE CLOSER TO WARMER GUIDANCE AND PERSISTENCE FROM MONDAY FOR
MAXIMUM TEMPERATURES TODAY. CLOUDS AND MILD DEW POINTS WILL KEEP
TEMPERATURES FROM DROPPING MUCH OVERNIGHT. HAVE RAISED MINIMUM
TEMPERATURES SLIGHTLY ACROSS THE PIEDMONT TONIGHT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
AS OF 330 AM EDT TUESDAY...
THE UPPER LEVEL PATTERN WILL REMAIN UNSETTLED AS THE WESTERN TROF
SPLINTERS INTO PIECES WITH SEVERAL BITS OF SHORT WAVE ENERGY MOVING IN
OUR DIRECTION INTERSPERSED WITH PERIODS OF GENERALLY FLAT RIDGING. AND
WITHOUT SOLID UPPER LEVEL SUPPORT TO MOVE IT ALONG...THE FRONTAL ZONE
AT THE SURFACE WILL SIMPLY LINGER OVER THE REGION THROUGH THE END OF
THE WEEK. AMPLE CONVERGENCE AND INSTABILITY IN THE FRONTAL ZONE WILL
KEEP UP WITH A CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY. BY FRIDAY
IT APPEARS THAT A SHORT WAVE REMNANT OF THE WESTERN TROF WILL SWING BY
TO OUR NORTH AND HELP PUSH THE FRONTAL BOUNDARY FURTHER TO THE SOUTH
AND ALLOW A WEDGE OF HIGH PRESSURE TO BUILD DOWN EAST OF THE
APPALACHIANS. HOWEVER ANY IMPROVEMENT IN OUR WEATHER LOOK TO BE
MARGINAL SINCE CLOUDS AND SOME LIGHT PRECIPITATION WILL ACCOMPANY THE
WEDGE. TEMPERATURES WILL GENERALLY BE A BIT ABOVE NORMAL THROUGH THE
END OF THE WEEK WITH HIGHS IN THE MID 70S TO AROUND 80 EAST OF THE BLUE
RIDGE...AND IN THE LOW TO MID 70S WEST.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 245 PM EDT MONDAY...
WEAK UPPER RIDGING THROUGH SATURDAY WILL KEEP PRECIP CHANCES CONFINED
TO ISOLATED/WIDELY SCATTERED IN COVERAGE. AT THE SFC...12Z ECMWF KEEPS
WEDGE IN PLACE THROUGH SATURDAY. WHILE TEMPS WERE BROUGHT DOWN A COUPLE
OF DEGREES DURING THIS TIME...THESE FORECAST VALUES STILL MAY BE TOO
WARM.
HOWEVER...BETTER CHANCES FOR MORE WIDESPREAD PRECIPITATION
ARRIVE LATER SUNDAY INTO MONDAY...DEPENDING ON THE ARRIVAL OF AN
OPENING UPPER LOW MOVING THROUGH THE OHIO VALLEY. AS IT TYPICAL
FOR THE LONG RANGE MODELS...THERE IS DISAGREEMENT IN THE TIMING
AND TRACK OF THIS SYSTEM...BUT INDIVIDUAL GEFS ENSEMBLE MEMBERS
SUGGEST THE BEST CHANCES FOR PRECIPITATION WILL BE LATE SUNDAY
INTO EARLY MONDAY...AND THIS IS THE TIME PERIOD WHERE THE POPS ARE
HIGHEST.
TEMPS ARE EXPECTED TO BE BELOW NORMAL EARLY WITH THE WEDGE IN
PLACE TO NEAR NORMAL LATER IN THE LONG TERM PERIOD.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 720 AM EDT TUESDAY...
A COLD FRONT EXTENDED FROM PENNSYLVANIA TO MISSOURI THIS MORNING.
THIS FRONT WILL MOVE SOUTH INTO THE MID ATLANTIC REGION TODAY.
WITH THE BOUNDARY IN THE AREA AND MOISTURE ON THE INCREASE...SCATTERED
SHOWERS AND THUNDERSTORM WITH MVFR CEILINGS AND VISIBILITIES WILL
DEVELOP THIS AFTERNOON...MAINLY ACROSS THE MOUNTAINS. BY THE LATE
MORNING SURFACE WIND GUSTS WILL BE IN THE 15 TO 20 KT RANGE.
MODELS BRING THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS INTO THE
AREA AFTER 3PM IN KLWB AND NOT UNTIL 5PM AT KDAN. MEDIUM
CONFIDENCE ON THE TIMING OF THE PRECIPITATION AND ON THE
OCCURRENCE OF AN ADDITIONAL PRECIPITATION OVERNIGHT.
EXTENDED AVIATION DISCUSSION...
THIS FRONT WILL REMAIN STALLED OVERHEAD WEDNESDAY...BEFORE A
STRONGER COLD FRONT ENTERS FROM THE WEST TO PUSH THE WEAKER FRONT
OFFSHORE. DURING THIS TIME...SCATTERED SHOWERS WITH A FEW
AFTERNOON THUNDERSTORMS APPEAR LIKELY. THE GREATEST CHANCE OF RAIN
AND MVFR/IFR CONDITIONS WILL ACCOMPANY THE STRONGER COLD FRONT ON
THURSDAY. SOME CLEARING SHOULD TAKE PLACE DURING FRIDAY...ALTHOUGH
A FEW MOUNTAIN SHOWERS AND MVFR CLOUDS ARE POSSIBLE.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/SK
SHORT TERM...PH
LONG TERM...PH
AVIATION...AMS/DS