Forecast Discussions mentioning any of
"HRRR" "RR" "RUC13" "RUC" received at GSD on 05/09/12
AREA FORECAST DISCUSSION
NWS FLAGSTAFF AZ
850 PM MST TUE MAY 8 2012
.SYNOPSIS...LOW PRESSURE MOVING THROUGH THE DESERT SOUTHWEST WILL
BRING COOLER TEMPERATURES WITH A CHANCE OF AFTERNOON SHOWERS AND
THUNDERSTORMS THROUGH THURSDAY. FAIR AND WARMER WEATHER WILL RETURN
TO THE AREA FROM FRIDAY THROUGH EARLY NEXT WEEK.
&&
.DISCUSSION...SHOWERS AND THUNDERSTORMS HAVE DIMINISHED IN COVERAGE
THIS EVENING. SOME OF THESE STORMS PRODUCED WIND GUSTS OF UP TO 40
MPH BUT LITTLE IN THE WAY OF RAINFALL. HRRR MODEL (HIGH RESOLUTION
RAPID REFRESH) SUGGESTS SOME SHOWER ACTIVITY WILL CONTINUE OVERNIGHT
BUT SHOULD REMAIN ISOLATED IN COVERAGE.
CURRENT FCST HANDLES THIS WELL AND NO UPDATES PLANNED.
&&
.PREV DISCUSSION (238 PM)...
FOR WEDNESDAY...ADDITIONAL MOISTURE IS FORECAST TO BE ADVECTED INTO
EAST-CENTRAL ARIZONA INCLUDING THE WHITE MOUNTAINS AND POSSIBLY AS
FAR NORTH AS FLAGSTAFF AND WINDOW ROCK. THIS MOISTURE IS CURRENTLY
LOCATED ACROSS SOUTHERN NEW MEXICO WHERE THERE ARE WIDESPREAD
THUNDERSTORMS THIS AFTERNOON. WE WILL CONTINUE THE CHANCE OF SHOWERS
AND THUNDERSTORMS OVER THE FORECAST AREA...WITH THE BEST CHANCE OVER
THE WHITE MTNS.
STARTING THURSDAY...DRYING WESTERLY FLOW IS SHOWN TO RETURN WITH
DECREASING PRECIP CHANCES FROM WEST TO EAST. THE MOISTURE IS SHOWN
TO LINGER OVER NEW MEXICO AND WE WILL KEEP A SLIGHT CHANCE OF
AFTERNOON THUNDERSTORMS ALONG THE STATE LINE THROUGH THE WEEKEND.
OTHERWISE DAYTIME TEMPS WILL WARM TO 5 TO 10 DEGREES ABOVE NORMAL
VALUES INTO EARLY NEXT WEEK. WIND SPEEDS THROUGHOUT THE 7-DAY
FORECAST...THOUGH LOCALLY BREEZY AT TIMES...WILL REMAIN BELOW WHAT
IS TYPICAL FOR A NORTHERN ARIZONA SPRING.
&&
.AVIATION...FOR THE 06Z PACKAGE...ISOLD -SHRA/-TSRA PSBL OVERNIGHT...
ESPECIALLY SOUTH OF A KSJN-KINW-KPRC LINE. AFT 18-20Z...ISOLD TO SCT
-SHRA/-TSRA WILL REDEVELOP...MOST PREVALENT FROM KPAN-KFLG-KE91
EASTWARD. GUSTY WINDS EXCEEDING 40 KTS AND ISOLATED MVFR VSBYS AND
CIGS ARE POSSIBLE WITH THUNDERSTORMS. AVIATION DISCUSSION NOT UPDATED
FOR AMENDMENTS.
&&
.FIRE WEATHER...A LOW PRESSURE SYSTEM WILL MOVE EASTWARD ACROSS
NORTHERN MEXICO WEDNESDAY...WITH RELATIVELY MOIST AIR WRAPPING
AROUND THE LOW THROUGH NORTHEASTERN ARIZONA. THE RESULT WILL BE
ISOLATED TO SCATTERED AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS AGAIN ON WEDNESDAY. SLIGHTLY WARMER TEMPERATURES AND
LIGHTER EASTERLY WINDS ARE EXPECTED. THUNDERSTORMS WILL LIKELY
PRODUCE LOW AMOUNTS OF PRECIPITATION BUT MAY CONTAIN LOCALLY STRONG
AND GUSTY WINDS. DRIER WESTERLY FLOW WILL INCREASE TEMPERATURES AND
REDUCE THUNDERSTORM COVERAGE FOR THURSDAY...WITH ONLY A SLIGHT
CHANCE FROM AROUND FLAGSTAFF EASTWARD.
FRIDAY THROUGH SUNDAY...WEAK WESTERLY FLOW ALOFT WILL BRING DRIER
CONDITIONS...ABOVE NORMAL TEMPERATURES...AND BREEZY AFTERNOON
SOUTHWESTERLY WINDS. A SLIGHT CHANCE FOR ISOLATED AFTERNOON AND
EVENING THUNDERSTORMS WILL CONTINUE OVER APACHE COUNTY.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC.........DB/JJ
AVIATION.......DB
FIRE WEATHER...DJO
FOR NORTHERN ARIZONA WEATHER INFORMATION VISIT
WEATHER.GOV/FLAGSTAFF
AREA FORECAST DISCUSSION
NWS MIAMI FL
1014 AM EDT MON MAY 7 2012
.UPDATE...THE SHORT TERM FORECAST REMAINS ON TRACK. A WEAKENING
FRONTAL BOUNDARY WILL PUSH SOUTH BUT REMAIN NORTH OF THE LOCAL
AREA TODAY, ALONG WITH THE BEST MID LEVEL ENERGY. SLIGHT CHANCE
POPS FOR THUNDERSTORMS SEEM REASONABLE THIS AFTERNOON, ESPECIALLY
FROM THE LAKE REGION AND ACROSS PALM BEACH COUNTY.
&&
.PREV DISCUSSION... /ISSUED 720 AM EDT MON MAY 7 2012/
AVIATION...
CLOUDS WILL SLOWLY INCREASE ACROSS SOUTH FLORIDA OVER THE NEXT 24
HOURS AS DEEPER MOISTURE PUSHES IN FROM THE NORTH. SHRAS WILL BE
POSSIBLE ACROSS THE AREA TOWARD THE LATE AFTERNOON HOURS...KEPT
VCSH MENTION AT ALL EAST COAST SITES. OTHERWISE...EASTERLY WINDS
AROUND 10 KTS FROM EAST COAST SEA BREEZE THIS AFTERNOON SHOULD
SUBSIDE AFTER 00Z. AT KAPF A SOUTHWESTERLY SEA BREEZE WILL DEVELOP
BY THE LATE MORNING AND CONTINUE THROUGH THE EARLY EVENING.
PREV DISCUSSION... /ISSUED 416 AM EDT MON MAY 7 2012/
DISCUSSION...WATER VAPOR IMAGERY SHOWS A TROUGH IN PLACE OVER
THE DEEP SOUTH. THIS FEATURE WILL MOVE SOUTHEAST OVER THE NEXT FEW
DAYS, REPLACING THE RIDGE THAT HAS BEEN IN PLACE ACROSS SOUTH FL.
MEANWHILE, MOISTURE WILL INCREASE AS WELL. IN FACT, THIS IS
HAPPENING ALREADY WITH GPS MET DATA SHOWING A SLOW RISE IN PWATS
SINCE LAST EVENING INTO THE 1.2-1.4 INCH RANGE, THOUGH MIAMI IS
STILL HOLDING AT 1.1 INCHES. AS MOISTURE INCREASES A TAD ALONG
WITH TROUGHING ACROSS THE AREA TUE-THU, THE RESULT WILL BE AN
INCREASING CHANCE OF SHOWERS AND THUNDERSTORMS, THOUGH CERTAINLY
NOT A WASHOUT. THEY WILL BE OF THE PULSE VARIETY DURING THE HEAT
OF THE DAY WITH FOCUS OVER THE INTERIOR-EAST COAST.
FOR THIS AFTERNOON, NOT AS HIGH OF CONFIDENCE IN A FEW
THUNDERSTORMS DEVELOPING AS COMPARED TO TUE-THU. HOWEVER, THIS
COULD OCCUR FROM THE INTERIOR TOWARDS THE WESTERN BROWARD METRO
AND ACROSS PALM BEACH COUNTY...SO HAVE SLIGHT CHANCE OF TSTORMS
ACROSS THIS AREA FOR THIS AFTERNOON. LATEST HRRR SHOWS JUST LIGHT
QPF OVER INLAND PALM BEACH/INLAND BROWARD DEVELOPING BY 4 PM WITH
MOST OF THE ACTION TO OUR NORTH OVER CENTRAL AND NORTH FL.
AS THE TROUGH MOVES IN OVERNIGHT, A FEW SHOWERS OR THUNDERSTORMS
COULD DEVELOP OVER THE GULF OF MEXICO, POSSIBLY MOVING ONSHORE THE
GULF COAST, SIGNALED SLIGHTLY BY THE ECMWF. SO ADDED SLIGHT CHANCE
POPS AFTER MIDNIGHT FOR THIS AREA. HIGHER CONFIDENCE IN SHOWER AND
TSTORM ACTIVITY DEVELOPING TUE- THU, AGAIN WITH FOCUS INTERIOR AND
EAST COAST DUE TO A WESTERLY STEERING FLOW.
GFS/ECMWF SHOW A WEAKENING COLD FRONT MOVING INTO SOUTH FL LATE
THU WHILE BECOMING DIFFUSE. BOTH GFS/ECMWF SHOW ANOTHER SHORTWAVE
MOVING INTO THE NORTHERN GULF NEXT WEEKEND, BUT WITH MOST OF THE
ACTIVE WEATHER OFF TO OUR NORTHWEST. SO MAINTAINED JUST SLIGHT
CHANCE POPS IN THE EXTENDED. TEMPS THROUGH THE PERIOD WILL REMAIN
SEASONABLY WARM.
MARINE...LIGHT WINDS WILL CONTINUE WITH SEAS GENERALLY 4 FT OR
LESS THROUGH THE PERIOD, EXCEPT POSSIBLY UP TO 5 FT OFF THE
NORTHERN PALM BEACH COAST TUE NIGHT ASSOCIATED WITH A SMALL NE
SWELL.
FIRE WEATHER...A FEW INTERIOR LOCALES SAW RH`S FALL TO JUST
BELOW 35 PERCENT YESTERDAY FOR A FEW HR. THE SLIGHT INCREASE IN
MOISTURE TODAY SHOULD KEEP RH`S ABOVE CRITICAL LEVELS TODAY AND
BEYOND.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 71 86 71 / 20 20 30 20
FORT LAUDERDALE 86 72 86 73 / 10 10 30 20
MIAMI 88 72 86 73 / 10 10 30 20
NAPLES 85 70 84 70 / 10 10 20 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
UPDATE...14/MJB
AREA FORECAST DISCUSSION
NWS MIAMI FL
720 AM EDT MON MAY 7 2012
.AVIATION...
CLOUDS WILL SLOWLY INCREASE ACROSS SOUTH FLORIDA OVER THE NEXT 24
HOURS AS DEEPER MOISTURE PUSHES IN FROM THE NORTH. SHRAS WILL BE
POSSIBLE ACROSS THE AREA TOWARD THE LATE AFTERNOON HOURS...KEPT
VCSH MENTION AT ALL EAST COAST SITES. OTHERWISE...EASTERLY WINDS
AROUND 10 KTS FROM EAST COAST SEA BREEZE THIS AFTERNOON SHOULD
SUBSIDE AFTER 00Z. AT KAPF A SOUTHWESTERLY SEA BREEZE WILL DEVELOP
BY THE LATE MORNING AND CONTINUE THROUGH THE EARLY EVENING.
&&
.PREV DISCUSSION... /ISSUED 416 AM EDT MON MAY 7 2012/
DISCUSSION...WATER VAPOR IMAGERY SHOWS A TROUGH IN PLACE OVER
THE DEEP SOUTH. THIS FEATURE WILL MOVE SOUTHEAST OVER THE NEXT FEW
DAYS, REPLACING THE RIDGE THAT HAS BEEN IN PLACE ACROSS SOUTH FL.
MEANWHILE, MOISTURE WILL INCREASE AS WELL. IN FACT, THIS IS
HAPPENING ALREADY WITH GPS MET DATA SHOWING A SLOW RISE IN PWATS
SINCE LAST EVENING INTO THE 1.2-1.4 INCH RANGE, THOUGH MIAMI IS
STILL HOLDING AT 1.1 INCHES. AS MOISTURE INCREASES A TAD ALONG
WITH TROUGHING ACROSS THE AREA TUE-THU, THE RESULT WILL BE AN
INCREASING CHANCE OF SHOWERS AND THUNDERSTORMS, THOUGH CERTAINLY
NOT A WASHOUT. THEY WILL BE OF THE PULSE VARIETY DURING THE HEAT
OF THE DAY WITH FOCUS OVER THE INTERIOR-EAST COAST.
FOR THIS AFTERNOON, NOT AS HIGH OF CONFIDENCE IN A FEW
THUNDERSTORMS DEVELOPING AS COMPARED TO TUE-THU. HOWEVER, THIS
COULD OCCUR FROM THE INTERIOR TOWARDS THE WESTERN BROWARD METRO
AND ACROSS PALM BEACH COUNTY...SO HAVE SLIGHT CHANCE OF TSTORMS
ACROSS THIS AREA FOR THIS AFTERNOON. LATEST HRRR SHOWS JUST LIGHT
QPF OVER INLAND PALM BEACH/INLAND BROWARD DEVELOPING BY 4 PM WITH
MOST OF THE ACTION TO OUR NORTH OVER CENTRAL AND NORTH FL.
AS THE TROUGH MOVES IN OVERNIGHT, A FEW SHOWERS OR THUNDERSTORMS
COULD DEVELOP OVER THE GULF OF MEXICO, POSSIBLY MOVING ONSHORE THE
GULF COAST, SIGNALED SLIGHTLY BY THE ECMWF. SO ADDED SLIGHT CHANCE
POPS AFTER MIDNIGHT FOR THIS AREA. HIGHER CONFIDENCE IN SHOWER AND
TSTORM ACTIVITY DEVELOPING TUE- THU, AGAIN WITH FOCUS INTERIOR AND
EAST COAST DUE TO A WESTERLY STEERING FLOW.
GFS/ECMWF SHOW A WEAKENING COLD FRONT MOVING INTO SOUTH FL LATE
THU WHILE BECOMING DIFFUSE. BOTH GFS/ECMWF SHOW ANOTHER SHORTWAVE
MOVING INTO THE NORTHERN GULF NEXT WEEKEND, BUT WITH MOST OF THE
ACTIVE WEATHER OFF TO OUR NORTHWEST. SO MAINTAINED JUST SLIGHT
CHANCE POPS IN THE EXTENDED. TEMPS THROUGH THE PERIOD WILL REMAIN
SEASONABLY WARM.
MARINE...LIGHT WINDS WILL CONTINUE WITH SEAS GENERALLY 4 FT OR
LESS THROUGH THE PERIOD, EXCEPT POSSIBLY UP TO 5 FT OFF THE
NORTHERN PALM BEACH COAST TUE NIGHT ASSOCIATED WITH A SMALL NE
SWELL.
FIRE WEATHER...A FEW INTERIOR LOCALES SAW RH`S FALL TO JUST
BELOW 35 PERCENT YESTERDAY FOR A FEW HR. THE SLIGHT INCREASE IN
MOISTURE TODAY SHOULD KEEP RH`S ABOVE CRITICAL LEVELS TODAY AND
BEYOND.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 71 86 71 / 20 20 30 20
FORT LAUDERDALE 86 72 86 73 / 10 10 30 20
MIAMI 88 72 86 73 / 10 10 30 20
NAPLES 85 70 84 70 / 10 10 20 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...14/MJB
AVIATION/RADAR...84/AK
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
500 AM EDT Mon May 7 2012
.SYNOPSIS...
The weather pattern remains quite complex over the Southeast this
morning, with several mesoscale features generated by convective
activity in the past 12-24 hours. We had quite a few thunderstorms
that developed yesterday across the area. In general, the storms
formed a common convective cold pool and pushed south eventually
weakening as they approached the Gulf of Mexico. These storms
produced sporadic wind damage and a few measured gusts in the
40-50kt range. The widespread thunderstorm development led to a
convectively overturned boundary layer, and we are still seeing
the effects of this early this morning. Our local forecast area is
essentially co-located with a minimum in both MUCAPE and boundary
layer dewpoints. This presents some challenges regarding the
convective forecast today, which will be discussed below. The
storms did produce some beneficial rainfall in our AL-GA zones.
Gauge-adjusted Q2 rainfall estimates were at least 0.50" in many
areas, with a few areas receiving up to 2-3" of rain. Things were
drier across the Florida Panhandle, as storms mostly started
dissipating by the time they arrived there.
Aloft, water vapor satellite and RUC analysis revealed that broad
cyclonic flow and a large area of slightly lower mid-level heights
had developed ESE over the past 24 hours, now centered over GA/SC.
Embedded within this region were two PV anomalies / MCVs. The
first was partially responsible for triggering storms in our area
today and is now moving quickly east over NE FL. The second is
moving more slowly over southern SC. At the surface, mesoscale
areas of high pressure were situated over SE AL and SW GA with
corresponding lower surface dewpoints. Greater low-level moisture
nearby was found in SE GA and along the FL Atlantic coast, as well
as just offshore over the Gulf of Mexico. A surface high pressure
ridge continued to build down the Carolinas.
&&
.SHORT TERM [Today through Wednesday]...
The primary focus was on trends through 06z Tuesday (today and
into this evening), with only minor tweaks made to the forecast
beyond that timeframe.
TODAY: Convection-allowing models are in much better agreement
regarding the convective evolution today. The PoPs derived from
the 4km NCEP WRF runs and our local 4km WRF-ARW were incorporated
into the grids for today - yielding a maximum in the FL Big Bend
and adjacent SC GA (70-80% PoPs). One potential pitfall is the
recovery of low-level moisture this morning. The dewpoint trends
this morning will probably tell the story: if they struggle to
rise into the mid-upper 60s, particularly in the aforementioned
area of higher PoPs, then convective coverage could be far more
limited than what we saw yesterday. In general, we expect decent
recovery across the eastern half of the area. RUC analyzed 0-1km
mixing ratio this morning showed a relative minimum of 9 g/kg near
Walton County, with a maximum of 14 g/kg near the GA coast, a
substantial west-to-east gradient. Meanwhile, area VWPs across S
GA and N FL all show increasing flow in the same layer with an
easterly component. As such, the eastern border of our forecast
area should be right near the nose of a broad easterly 0-1km
moisture transport maximum by 18z, and would be a favorable
location for convective initiation.
Severe weather potential today looks to be lower than yesterday.
Model forecast soundings almost all show slightly warmer mid-level
temperatures with slightly lower surface dewpoints, which yields a
shorter and narrower CAPE profile overall. However, models that
don`t erroneously convect earlier in the morning show maximum
delta thetae values around 20-22C with MLCAPE around 1000-1500
j/kg, which could support some isolated severe downbursts. The 5%
probabilities from SPC on the initial SWODY1 seem reasonable.
Storm motions will be very slow today, generally 10 knots or less
in the absence of organized and sizable cold pools. Therefore,
localized heavy rainfall and flooding cannot be ruled out.
Finally, high temperatures yesterday were well in excess of model
guidance. Many highs in the 90s were recorded with TLH at 93 and
VLD at 97. With 850mb temperatures only about 1C cooler today, and
limited cloud coverage prior to convective initiation, it seems
likely that many areas could reach around 90 again today.
TUESDAY AND WEDNESDAY: Very few notable changes were made in these
periods. The high temperatures were nudged up slightly each day
with forecast low-level temperature profiles expected to remain
roughly the same as today. In the big picture, the forecast will
be very similar for the entire Monday-Wednesday period, with
mesoscale details ultimately determining where the most storms are
focused each day.
.LONG TERM [Wednesday Night through next Monday]...
Not too many changes were made from the prior extended forecast,
as both the ECMWF and GFS are in very good agreement with the Cold
Frontal Passage on Wednesday Night into Thursday morning. However,
the fair, cooler, and drier air building in behind it may only
last for 2 to 3 days now (rest of Thu into Sat), as the unusual
and anomalously active subtropical jet stream for this time of
year appears poised to send yet an another Upper Level Shortwave
in our direction over the latter half of the weekend into early
next week. The new 00 UTC run of ECMWF is especially active with
this system, so PoPs were adjusted upward a bit to blend in with
the GFS. If the GFS trends more towards the Euro on later runs, it
could be a very wet period with plenty of beneficial rainfall from
Sunday through Tuesday of next week, which is certainly much
needed across our drought stricken area.
&&
.AVIATION [through 06z Tuesday]...
Had to essentially re-write the entire first portion of the
Aviation Discussion for the 06Z package, as the drier air that has
advected in behind Sunday`s MCS has caused a fairly quick erosion
of the Dense Fog at DHN, and now it appears that most sites are
likely to only experience a period of MVFR conditions into the
early morning hours, if at all. However, will still need to keep a
close eye on DHN, as some locations not too far to the north like
Troy, are continuing to deteriorate. Today, we could see fairly
similar conditions as we witnessed on Sunday, with good chances
for afternoon thunderstorms accompanied some gusty winds, likely
propagating from a NE-SW fashion during the afternoon hours, but
wind gusts are not expected to be as nearly as strong with less
daytime heating and destabilization, aided by the drier air mass
that has pushed in from the north behind the prior MCS.
&&
.MARINE...
A benign weather pattern will continue over the coastal waters
with light winds and seas 1 foot or less expected through Tuesday
Night. A slight increase in winds is expected around a cold front
passage Wednesday into Thursday, but conditions should remain
below what would necessitate a cautionary headline.
&&
.FIRE WEATHER...
Plenty of low level moisture and elevated rain chances should
preclude any fire weather concerns through at least the middle of
next week, with significantly drier conditions not expected until
Thursday and Friday.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 89 66 88 66 87 / 60 30 50 40 50
Panama City 84 68 82 69 83 / 40 30 40 30 40
Dothan 87 66 86 67 85 / 50 30 50 40 40
Albany 86 66 87 65 86 / 60 40 50 40 50
Valdosta 92 65 89 65 89 / 70 50 50 40 50
Cross City 89 64 88 65 86 / 60 40 40 40 50
Apalachicola 82 68 81 69 82 / 40 20 30 30 40
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...None.
GA...None.
FL...None.
GM...None.
&&
$$
Synopsis...Lamers
Short Term...Lamers
Long Term...Gould
Aviation...Gould
Marine...Lamers
Fire Weather...Gould
AREA FORECAST DISCUSSION
NWS MIAMI FL
416 AM EDT MON MAY 7 2012
.DISCUSSION...WATER VAPOR IMAGERY SHOWS A TROUGH IN PLACE OVER
THE DEEP SOUTH. THIS FEATURE WILL MOVE SOUTHEAST OVER THE NEXT FEW
DAYS, REPLACING THE RIDGE THAT HAS BEEN IN PLACE ACROSS SOUTH FL.
MEANWHILE, MOISTURE WILL INCREASE AS WELL. IN FACT, THIS IS
HAPPENING ALREADY WITH GPS MET DATA SHOWING A SLOW RISE IN PWATS
SINCE LAST EVENING INTO THE 1.2-1.4 INCH RANGE, THOUGH MIAMI IS
STILL HOLDING AT 1.1 INCHES. AS MOISTURE INCREASES A TAD ALONG
WITH TROUGHING ACROSS THE AREA TUE-THU, THE RESULT WILL BE AN
INCREASING CHANCE OF SHOWERS AND THUNDERSTORMS, THOUGH CERTAINLY
NOT A WASHOUT. THEY WILL BE OF THE PULSE VARIETY DURING THE HEAT
OF THE DAY WITH FOCUS OVER THE INTERIOR-EAST COAST.
FOR THIS AFTERNOON, NOT AS HIGH OF CONFIDENCE IN A FEW
THUNDERSTORMS DEVELOPING AS COMPARED TO TUE-THU. HOWEVER, THIS
COULD OCCUR FROM THE INTERIOR TOWARDS THE WESTERN BROWARD METRO
AND ACROSS PALM BEACH COUNTY...SO HAVE SLIGHT CHANCE OF TSTORMS
ACROSS THIS AREA FOR THIS AFTERNOON. LATEST HRRR SHOWS JUST LIGHT
QPF OVER INLAND PALM BEACH/INLAND BROWARD DEVELOPING BY 4 PM WITH
MOST OF THE ACTION TO OUR NORTH OVER CENTRAL AND NORTH FL.
AS THE TROUGH MOVES IN OVERNIGHT, A FEW SHOWERS OR THUNDERSTORMS
COULD DEVELOP OVER THE GULF OF MEXICO, POSSIBLY MOVING ONSHORE THE
GULF COAST, SIGNALED SLIGHTLY BY THE ECMWF. SO ADDED SLIGHT CHANCE
POPS AFTER MIDNIGHT FOR THIS AREA. HIGHER CONFIDENCE IN SHOWER AND
TSTORM ACTIVITY DEVELOPING TUE- THU, AGAIN WITH FOCUS INTERIOR AND
EAST COAST DUE TO A WESTERLY STEERING FLOW.
GFS/ECMWF SHOW A WEAKENING COLD FRONT MOVING INTO SOUTH FL LATE
THU WHILE BECOMING DIFFUSE. BOTH GFS/ECMWF SHOW ANOTHER SHORTWAVE
MOVING INTO THE NORTHERN GULF NEXT WEEKEND, BUT WITH MOST OF THE
ACTIVE WEATHER OFF TO OUR NORTHWEST. SO MAINTAINED JUST SLIGHT
CHANCE POPS IN THE EXTENDED. TEMPS THROUGH THE PERIOD WILL REMAIN
SEASONABLY WARM.
&&
.MARINE...LIGHT WINDS WILL CONTINUE WITH SEAS GENERALLY 4 FT OR
LESS THROUGH THE PERIOD, EXCEPT POSSIBLY UP TO 5 FT OFF THE
NORTHERN PALM BEACH COAST TUE NIGHT ASSOCIATED WITH A SMALL NE
SWELL.
&&
.FIRE WEATHER...A FEW INTERIOR LOCALES SAW RH`S FALL TO JUST
BELOW 35 PERCENT YESTERDAY FOR A FEW HR. THE SLIGHT INCREASE IN
MOISTURE TODAY SHOULD KEEP RH`S ABOVE CRITICAL LEVELS TODAY AND
BEYOND.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 71 86 71 / 20 20 30 20
FORT LAUDERDALE 86 72 86 73 / 10 10 30 20
MIAMI 88 72 86 73 / 10 10 30 20
NAPLES 85 70 84 70 / 10 10 20 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...57/GREGORIA
AVIATION/RADAR...10/CD
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1107 AM CDT MON MAY 7 2012
.DISCUSSION...
320 AM CDT
SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT...
TODAY AND TONIGHT...AN INVERTED TROUGH EXTENDS FROM NORTH CENTRAL
TEXAS THROUGH NORTHEASTERN ILLINOIS THIS MORNING. THE LOWS WARM
FRONT ARCS FROM SPRINGFIELD ILLINOIS...THROUGH DELAWARE COUNTY
INDIANA. CONVECTION HAS REMAINED ACTIVE OVERNIGHT INTO EARLY THIS
MORNING...ESPECIALLY ALONG AND NORTH OF THE WARM FRONT. A LARGE
OUTFLOW BOUNDARY IS PUSHING SOUTH AWAY FROM THE MAIN LINE OF
STORMS...WITH ISOLATED STORMS BEING INITIATED BY THE OUTFLOW
BOUNDARY. THE EVENT HAS TRANSITIONED FROM SEVERE WEATHER TO A
HEAVY RAIN/FLASH FLOODING DUE TO SLOW MOVING STORMS AND PW VALUES
BETWEEN 1.5 TO 2 INCHES.
THE MAIN LOW PASSES THROUGH CENTRAL ILLINOIS TODAY AS DOES THE
MOISTURE AXIS. WINDS FLIP TO NORTHWEST BEHIND THE LOW AND PW
VALUES DROP FROM AROUND 1.5 INCHES TO 0.75 INCHES LATE TONIGHT.
GIVEN THE NOCTURNAL CONVECTION AND CLOUDY FORECAST...KEPT TEMPS A
FEW DEGREES BELOW GUIDANCE. WITH LESS HEATING TOMORROW...NOT
EXPECTING AS MUCH CAPE. THE NAM CURRENTLY FEATURES A MAX CAPE OF
AROUND 2000 J/KG EARLY ALONG AND SOUTHEAST OF THE I-55 CORRIDOR
WITH VALUES DECLINING THROUGH THE DAY. GIVEN THE NAMS WET BIAS AND
THEREFORE TYPICAL OVERESTIMATION OF CAPE...THINKING 1500 J/KG OR
LESS IS MOST LIKELY. 0-6 KM SHEAR ALSO DECREASES AS THE INVERTED
TROUGH MOVES OFF...WITH 35 KT OR LESS THROUGHOUT THE REGION.
MODEL SOUNDINGS INDICATE WARM AIR WILL BE SEEPING IN ALOFT AHEAD OF
THE WARM FRONT. THE WARM AIR WILL CAUSE A CAP WHICH WILL FURTHER
HINDER STORM DEVELOPMENT AND THEREFORE SEVERE WEATHER. BASED ON
THE PARAMETERS...THINKING THUNDERSTORMS WILL BE MORE LIKELY
SOUTHEAST AND ALONG THE 1-55 CORRIDOR WHERE THE ENVIRONMENT IS
MORE FAVORABLE. MAIN THREAT WILL BE HEAVY RAIN...ESPECIALLY WITH
THE VERY MOIST AIR MASS OVERHEAD.
TONIGHT...WENT WITH THE QUICKER NAM AND GFS SOLUTIONS IN REGARD TO
THE NOCTURNAL PRECIP. EXPECTING PRECIP TO MOVE QUICKLY OFF TO THE
EAST BEHIND THE DEPARTING LOW...ESPECIALLY SINCE MOISTURE WILL BE
RETREATING RAPIDLY. STAYED WITH GUIDANCE ON OVERNIGHT LOWS. THE
NIGHT WILL START CLOUDY AND CLEAR OUT LATE...LEADING TO A SLOW
DROP IN TEMPS UNTIL THE SKY CLEARS.
TUESDAY...THE DAY STARTS OFF DRY BEHIND THE FRONT AND LOW PASSAGE.
THE UPPER LEVEL TROUGH SWINGS THROUGH WISCONSIN AND NORTHERN
ILLINOIS TUESDAY AFTERNOON AND EVENING. MODELS INDICATE CONVECTION
WILL FORM TUESDAY AFTERNOON ACROSS WISCONSIN. CAPE VALUES ARE
MEAGER AT BEST AND WITH THE TROUGH SINKING SOUTH OUT OF CANADA...AM
QUESTIONING HOW MUCH MOISTURE THE MODELS KEEP WITH THIS SYSTEM.
DOWNPLAYING THE PRECIP POTENTIAL IN THE LOT CWA...THINKING THE
MAJORITY OF PRECIP WILL DRY UP BEFORE ENTERING NORTHERN IL. ONCE
AGAIN WENT WITH GUIDANCE FOR TEMPS...AS THE DAY WILL BEGIN SUNNY
WITH INCREASING CLOUD COVER.
BOTH THE GFS NAM...AND THE ECMWF TO A LESSER EXTENT...SUGGEST A
MCS WILL FORM TUESDAY NIGHT IN EAST CENTRAL WI AND SINK SOUTH OVER
THE LAKE. WITH ALL 3 MODELS DEPICTING A SIMILAR STORY...DECIDED TO
PUT IN SLIGHT CHANCE TO CHANCE POPS FOR TUESDAY NIGHT...HOWEVER
CONFIDENCE IS LOW REGARDING WHERE THE ACTUAL MCS WOULD FORM IF AT
ALL.
WEDNESDAY...A DRY PATTERN BEGINS ON WEDNESDAY AS HIGH PRESSURE MOVES
IN FROM THE CENTRAL PLAINS. SLIGHTLY COOLER TEMPS EXPECTED WITH
NORTHWEST UPPER LEVEL FLOW OUT OF CANADA.
JEE
EXTENDED...THURSDAY THROUGH SUNDAY...
410 AM CDT
OVERALL...THE EXTENDED FORECAST LOOKS DRY WITH AVERAGE TEMPS. A
BROAD RIDGE SETS UP OVER THE GREAT PLAINS MID WEEK AND PASSES OVER
THE MISSISSIPPI RIVER VALLEY LATE IN THE WEEK. NEXT CHANCE OF
PRECIP ARRIVES FRIDAY NIGHT AS A SURFACE LOW PASSES NORTH OF THE
GREAT LAKES AND ITS COLD FRONT PASSES THROUGH THE AREA LATE FRIDAY
NIGHT. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO FORM ALONG THE
COLD FRONT AND PERSIST THROUGH THE EARLY PART OF SATURDAY. THE
ECMWF HAS THE BAND OF PRECIP MOVING THROUGH THE AREA FASTER THAN
THE GFS...BUT AT THIS DISTANCE...DECIDED TO KEEP PRECIP IN THE
FORECAST SPANNING BOTH FORECASTS.
FOR TEMPS...MAX TEMPS REMAIN AROUND THE CLIMATIC NORMAL...IN THE MID
60S TO LOW 70S. OVERNIGHT LOWS APPEAR TO REMAIN WELL ABOVE FREEZING
THROUGHOUT THE EXTENDED.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* -RA ENDING 17Z-18Z.
* RATE OF IMPROVEMENT FROM MVFR TO VFR THIS AFTERNOON.
* POSSIBLE VEERING WIND TO OUT OF NNE FOR EARLY AFTERNOON...THEN
BACKING TO NNW AGAIN LATE AFTERNOON.
TRS
//DISCUSSION...UPDATED 14Z...
MID LEVEL LOW CURRENTLY MOVING E ACROSS NORTHERN IL PRODUCING -RA
OCNL RA AND ACCOMPANYING MVFR AND TEMPO IFR CONDITIONS TO REACH NE
IL AROUND 18Z AND THEN CONTINUE ACROSS FAR SOUTHERN LAKE MI AND
NORTHERN IND DURING THE REST OF THE AFTERNOON.
BACK EDGE OF -RA BASED ON BOTH MODEL FORECAST OF FEATURE POSITION AS
WELL AS STRAIGHT EXTRAPOLATION HAVE -RA ENDING CHI TERMINALS
17Z OR SO. LARGE AREA OF IFR CEILINGS ACROSS ALL BUT NW AND FAR W
CENTRAL WI EXTENDS DOWN TO E CENTRAL IA SO PREVAILING MVFR CIGS AT
17Z AND AND VFR AT 19Z MAY BE A BIT PREMATURE AND GOOD CHANCE WILL
HAVE TO DELAY FOR AT LEAST A FEW HRS.
SFC PRES FALL CENTER FOLLOWING SFC LOW OVER SOUTHERN LAKE MI WAS
OVER FAR NE IL AT 13Z AND LOCAL SFC WINDS HAD FALLEN OFF TO BLO
10KT. MAIN SFC LOW CENTERED OVER SOUTHERN IND PROGGED TO NE IND BY
18Z. NEWEST RUC13 AT NAM12 SHOW A SUBTLE SFC HI OVER FAR SOUTHERN
LAKE MI THIS AFTERNOON WITH SFC WINDS RESPONDING BY VEERING TO N
AND NE AND THUS TRENDS WILL HAVE TO BE WATCHED TO SE IF THIS
DEVELOPS... THOUGH EVEN IF IT DOES FORECAST WINDS SPEEDS ARE BLO
10 KT.
CHANCES OF TS LOW AND WILL CONT TO DECREASE TODAY AS STABLE
CONDITIONS TO ONLY BECOME MORE SO...ESPECIALLY IF LOW CLOUDS
LINGER WELL INTO THE AFTERNOON.
TRS
PREVIOUS DISCUSSION...UPDATED 12Z...
AREA OF RAIN WITH EMBEDDED THUNDERSTORMS ENTERING INTO NORTHWEST
IL HAS SLOWLY WEAKENED AND HAVE BACKED OFF THUNDER MENTION TO JUST
VCTS AS NEW DEVELOPMENT IS STILL POSSIBLE. BUT EXPECT BULK OF THE
ACTIVITY TO BE LIGHT/MODERATE RAIN THROUGH MID/LATE MORNING WITH A
FEW SHOWERS PERHAPS LINGERING INTO THE EARLY AFTERNOON.
LOW CIGS HAVE DEVELOPED BUT STILL APPEAR TO BE BOUNCING AROUND
QUITE A BIT. WITH THE SURFACE LOW NOW EAST OF CMI...WINDS HAVE
SHIFTED AROUND TO THE NORTHWEST AND THINK LIFR CIGS SHOULD LIFT
THROUGH IFR INTO LOW MVFR THIS MORNING THOUGH CONFIDENCE ON EXACT
CLOUD HEIGHTS AS WELL AS THEIR DURATION IS STILL LOW. POSSIBLE
MVFR CIGS COULD PERSIST INTO THIS AFTERNOON AND WILL NEED TO BE
MONITORED THIS MORNING.
AS NOTED...WINDS SHIFTED WESTERLY AND GUSTY IN A FEW LOCATIONS BUT
SHOULD DIMINISH OVER THE NEXT FEW HRS AS THEY TURN BACK MORE
NORTHERLY. WINDS REMAIN NORTHERLY INTO THIS AFTERNOON BUT MODELS
HINTING AT A WEAK RIDGE DEVELOPING ALONG THE WEST SIDE OF THE LAKE
BY EVENING WHICH MAY ALLOW WINDS TO SWING AROUND TO THE NORTHEAST.
NOT TOO CONFIDENT THAT WILL HAPPEN AND WHILE ITS NOT IN THE THIS
SET OF TAFS...IT REMAINS A POSSIBILITY. WINDS WILL THEN SHIFT BACK
AROUND LIGHT NORTHWESTERLY LATER THIS EVENING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE -RA ENDS 17Z-18Z TIME FRAME.
* HIGH CONFIDENCE MINIMAL TO NIL THREAT FOR TS.
* HIGH CONFIDENCE PREVAILING MVFR TEMPO IFR TIL EARLY AFTERNOON.
* MEDIUM CONFIDENCE IMPROVEMENT TO VFR BY MID AFTERNOON.
* HIGH CONFIDENCE SFC WINDS GENERALLY BLO 10KT.
* MEDIUM CONFIDENCE WIND DIR NNW-NNE THRU AFTERNOON.
TRS
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
* TUESDAY NIGHT...CHANCE OF SHRA/MVFR LATE.
* WEDNESDAY...CHANCE OF SHRA. MVFR POSSIBLE EARLY.
* THURSDAY...VFR.
* FRIDAY...VFR. CHANCE OF SHRA FRIDAY NIGHT.
* SATURDAY...CHANCE OF SHRA/SLIGHT CHANCE OF TSRA.
* SUNDAY...VFR. CHANCE OF SHRA. CMS
&&
.MARINE...
317 AM...LOW PRESSURE OVER CENTRAL IL WILL LIFT NORTHEAST ACROSS
NORTHERN INDIANA TODAY REACHING LAKE ERIE TONIGHT. THERE COULD BE A
FEW HOUR PERIOD EARLY THIS MORNING WHERE WINDS OVER SOUTHERN LAKE
MICHIGAN GUST INTO THE 15-25 KT RANGE AS THE LOW APPROACHES WITH A
SOUTHEAST DIRECTION SHIFTING TO THE NORTHEAST THIS MORNING. WINDS
WILL THEN SHIFT NORTHERLY AND DIMINISH INTO THE 10-15 KT RANGE
THIS AFTERNOON. A WEAK RIDGE MAY ALLOW WINDS TO DIMINISH EVEN
FURTHER ALONG THE WESTERN SIDE OF THE LAKE. A SECOND LOW WILL MOVE
SOUTHEAST ACROSS THE NORTHERN LAKES TONIGHT AND MERGE WITH THE
FIRST LOW LIFTING NORTHEAST ACROSS THE EASTERN LAKES ON TUESDAY. A
COLD FRONT WILL THEN MOVE SOUTH ACROSS THE LAKE TUESDAY NIGHT INTO
WEDNESDAY MORNING WITH NORTHERLY WINDS POSSIBLY INCREASING TO
15-25 KT. A LARGE RIDGE OF HIGH PRESSURE WILL THEN BUILD EAST
ACROSS THE LAKES REGION WEDNESDAY NIGHT INTO THURSDAY. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
928 AM CDT MON MAY 7 2012
.DISCUSSION...
320 AM CDT
SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT...
TODAY AND TONIGHT...AN INVERTED TROUGH EXTENDS FROM NORTH CENTRAL
TEXAS THROUGH NORTHEASTERN ILLINOIS THIS MORNING. THE LOWS WARM
FRONT ARCS FROM SPRINGFIELD ILLINOIS...THROUGH DELAWARE COUNTY
INDIANA. CONVECTION HAS REMAINED ACTIVE OVERNIGHT INTO EARLY THIS
MORNING...ESPECIALLY ALONG AND NORTH OF THE WARM FRONT. A LARGE
OUTFLOW BOUNDARY IS PUSHING SOUTH AWAY FROM THE MAIN LINE OF
STORMS...WITH ISOLATED STORMS BEING INITIATED BY THE OUTFLOW
BOUNDARY. THE EVENT HAS TRANSITIONED FROM SEVERE WEATHER TO A
HEAVY RAIN/FLASH FLOODING DUE TO SLOW MOVING STORMS AND PW VALUES
BETWEEN 1.5 TO 2 INCHES.
THE MAIN LOW PASSES THROUGH CENTRAL ILLINOIS TODAY AS DOES THE
MOISTURE AXIS. WINDS FLIP TO NORTHWEST BEHIND THE LOW AND PW
VALUES DROP FROM AROUND 1.5 INCHES TO 0.75 INCHES LATE TONIGHT.
GIVEN THE NOCTURNAL CONVECTION AND CLOUDY FORECAST...KEPT TEMPS A
FEW DEGREES BELOW GUIDANCE. WITH LESS HEATING TOMORROW...NOT
EXPECTING AS MUCH CAPE. THE NAM CURRENTLY FEATURES A MAX CAPE OF
AROUND 2000 J/KG EARLY ALONG AND SOUTHEAST OF THE I-55 CORRIDOR
WITH VALUES DECLINING THROUGH THE DAY. GIVEN THE NAMS WET BIAS AND
THEREFORE TYPICAL OVERESTIMATION OF CAPE...THINKING 1500 J/KG OR
LESS IS MOST LIKELY. 0-6 KM SHEAR ALSO DECREASES AS THE INVERTED
TROUGH MOVES OFF...WITH 35 KT OR LESS THROUGHOUT THE REGION.
MODEL SOUNDINGS INDICATE WARM AIR WILL BE SEEPING IN ALOFT AHEAD OF
THE WARM FRONT. THE WARM AIR WILL CAUSE A CAP WHICH WILL FURTHER
HINDER STORM DEVELOPMENT AND THEREFORE SEVERE WEATHER. BASED ON
THE PARAMETERS...THINKING THUNDERSTORMS WILL BE MORE LIKELY
SOUTHEAST AND ALONG THE 1-55 CORRIDOR WHERE THE ENVIRONMENT IS
MORE FAVORABLE. MAIN THREAT WILL BE HEAVY RAIN...ESPECIALLY WITH
THE VERY MOIST AIR MASS OVERHEAD.
TONIGHT...WENT WITH THE QUICKER NAM AND GFS SOLUTIONS IN REGARD TO
THE NOCTURNAL PRECIP. EXPECTING PRECIP TO MOVE QUICKLY OFF TO THE
EAST BEHIND THE DEPARTING LOW...ESPECIALLY SINCE MOISTURE WILL BE
RETREATING RAPIDLY. STAYED WITH GUIDANCE ON OVERNIGHT LOWS. THE
NIGHT WILL START CLOUDY AND CLEAR OUT LATE...LEADING TO A SLOW
DROP IN TEMPS UNTIL THE SKY CLEARS.
TUESDAY...THE DAY STARTS OFF DRY BEHIND THE FRONT AND LOW PASSAGE.
THE UPPER LEVEL TROUGH SWINGS THROUGH WISCONSIN AND NORTHERN
ILLINOIS TUESDAY AFTERNOON AND EVENING. MODELS INDICATE CONVECTION
WILL FORM TUESDAY AFTERNOON ACROSS WISCONSIN. CAPE VALUES ARE
MEAGER AT BEST AND WITH THE TROUGH SINKING SOUTH OUT OF CANADA...AM
QUESTIONING HOW MUCH MOISTURE THE MODELS KEEP WITH THIS SYSTEM.
DOWNPLAYING THE PRECIP POTENTIAL IN THE LOT CWA...THINKING THE
MAJORITY OF PRECIP WILL DRY UP BEFORE ENTERING NORTHERN IL. ONCE
AGAIN WENT WITH GUIDANCE FOR TEMPS...AS THE DAY WILL BEGIN SUNNY
WITH INCREASING CLOUD COVER.
BOTH THE GFS NAM...AND THE ECMWF TO A LESSER EXTENT...SUGGEST A
MCS WILL FORM TUESDAY NIGHT IN EAST CENTRAL WI AND SINK SOUTH OVER
THE LAKE. WITH ALL 3 MODELS DEPICTING A SIMILAR STORY...DECIDED TO
PUT IN SLIGHT CHANCE TO CHANCE POPS FOR TUESDAY NIGHT...HOWEVER
CONFIDENCE IS LOW REGARDING WHERE THE ACTUAL MCS WOULD FORM IF AT
ALL.
WEDNESDAY...A DRY PATTERN BEGINS ON WEDNESDAY AS HIGH PRESSURE MOVES
IN FROM THE CENTRAL PLAINS. SLIGHTLY COOLER TEMPS EXPECTED WITH
NORTHWEST UPPER LEVEL FLOW OUT OF CANADA.
JEE
EXTENDED...THURSDAY THROUGH SUNDAY...
410 AM CDT
OVERALL...THE EXTENDED FORECAST LOOKS DRY WITH AVERAGE TEMPS. A
BROAD RIDGE SETS UP OVER THE GREAT PLAINS MID WEEK AND PASSES OVER
THE MISSISSIPPI RIVER VALLEY LATE IN THE WEEK. NEXT CHANCE OF
PRECIP ARRIVES FRIDAY NIGHT AS A SURFACE LOW PASSES NORTH OF THE
GREAT LAKES AND ITS COLD FRONT PASSES THROUGH THE AREA LATE FRIDAY
NIGHT. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO FORM ALONG THE
COLD FRONT AND PERSIST THROUGH THE EARLY PART OF SATURDAY. THE
ECMWF HAS THE BAND OF PRECIP MOVING THROUGH THE AREA FASTER THAN
THE GFS...BUT AT THIS DISTANCE...DECIDED TO KEEP PRECIP IN THE
FORECAST SPANNING BOTH FORECASTS.
FOR TEMPS...MAX TEMPS REMAIN AROUND THE CLIMATIC NORMAL...IN THE MID
60S TO LOW 70S. OVERNIGHT LOWS APPEAR TO REMAIN WELL ABOVE FREEZING
THROUGHOUT THE EXTENDED.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* RAIN THRU REST OF MORNING WITH MVFR AND TEMPO IFR.
* RATE OF IMPROVEMENT TO VFR THIS AFTERNOON.
* POSSIBLE WIND SHIFT TO OUT OF NE-ENE THIS AFTERNOON.
TRS
//DISCUSSION...UPDATED 14Z...
MID LEVEL LOW CURRENTLY MOVING E ACROSS NORTHERN IL PRODUCING -RA
OCNL RA AND ACCOMPANYING MVFR AND TEMPO IFR CONDITIONS TO REACH NE
IL AROUND 18Z AND THEN CONTINUE ACROSS FAR SOUTHERN LAKE MI AND
NORTHERN IND DURING THE REST OF THE AFTERNOON.
BACK EDGE OF -RA BASED ON BOTH MODEL FORECAST OF FEATURE POSITION AS
WELL AS STRAIGHT EXTRAPOLATION HAVE -RA ENDING CHI TERMINALS
17Z OR SO. LARGE AREA OF IFR CEILINGS ACROSS ALL BUT NW AND FAR W
CENTRAL WI EXTENDS DOWN TO E CENTRAL IA SO PREVAILING MVFR CIGS AT
17Z AND AND VFR AT 19Z MAY BE A BIT PREMATURE AND GOOD CHANCE WILL
HAVE TO DELAY FOR AT LEAST A FEW HRS.
SFC PRES FALL CENTER FOLLOWING SFC LOW OVER SOUTHERN LAKE MI WAS
OVER FAR NE IL AT 13Z AND LOCAL SFC WINDS HAD FALLEN OFF TO BLO
10KT. MAIN SFC LOW CENTERED OVER SOUTHERN IND PROGGED TO NE IND BY
18Z. NEWEST RUC13 AT NAM12 SHOW A SUBTLE SFC HI OVER FAR SOUTHERN
LAKE MI THIS AFTERNOON WITH SFC WINDS RESPONDING BY VEERING TO N
AND NE AND THUS TRENDS WILL HAVE TO BE WATCHED TO SE IF THIS
DEVELOPS... THOUGH EVEN IF IT DOES FORECAST WINDS SPEEDS ARE BLO
10 KT.
CHANCES OF TS LOW AND WILL CONT TO DECREASE TODAY AS STABLE
CONDITIONS TO ONLY BECOME MORE SO...ESPECIALLY IF LOW CLOUDS
LINGER WELL INTO THE AFTERNOON.
TRS
PREVIOUS DISCUSSION...UPDATED 12Z...
AREA OF RAIN WITH EMBEDDED THUNDERSTORMS ENTERING INTO NORTHWEST
IL HAS SLOWLY WEAKENED AND HAVE BACKED OFF THUNDER MENTION TO JUST
VCTS AS NEW DEVELOPMENT IS STILL POSSIBLE. BUT EXPECT BULK OF THE
ACTIVITY TO BE LIGHT/MODERATE RAIN THROUGH MID/LATE MORNING WITH A
FEW SHOWERS PERHAPS LINGERING INTO THE EARLY AFTERNOON.
LOW CIGS HAVE DEVELOPED BUT STILL APPEAR TO BE BOUNCING AROUND
QUITE A BIT. WITH THE SURFACE LOW NOW EAST OF CMI...WINDS HAVE
SHIFTED AROUND TO THE NORTHWEST AND THINK LIFR CIGS SHOULD LIFT
THROUGH IFR INTO LOW MVFR THIS MORNING THOUGH CONFIDENCE ON EXACT
CLOUD HEIGHTS AS WELL AS THEIR DURATION IS STILL LOW. POSSIBLE
MVFR CIGS COULD PERSIST INTO THIS AFTERNOON AND WILL NEED TO BE
MONITORED THIS MORNING.
AS NOTED...WINDS SHIFTED WESTERLY AND GUSTY IN A FEW LOCATIONS BUT
SHOULD DIMINISH OVER THE NEXT FEW HRS AS THEY TURN BACK MORE
NORTHERLY. WINDS REMAIN NORTHERLY INTO THIS AFTERNOON BUT MODELS
HINTING AT A WEAK RIDGE DEVELOPING ALONG THE WEST SIDE OF THE LAKE
BY EVENING WHICH MAY ALLOW WINDS TO SWING AROUND TO THE NORTHEAST.
NOT TOO CONFIDENT THAT WILL HAPPEN AND WHILE ITS NOT IN THE THIS
SET OF TAFS...IT REMAINS A POSSIBILITY. WINDS WILL THEN SHIFT BACK
AROUND LIGHT NORTHWESTERLY LATER THIS EVENING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH CONFIDENCE RA PERSISTS THRU MORNING.
* HIGH CONFIDENCE MINIMAL THREAT FOR TS.
* HIGH CONFIDENCE PREVAILING LIFR AND TEMPO IFR THROUGH MORNING.
* MEDIUM CONFIDENCE IMPROVEMENT TO VFR BY MID AFTERNOON.
* HIGH CONFIDENCE WINDS REST OF A.M.
* MEDIUM CONFIDENCE WINDS P.M.
TRS
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
* TUESDAY NIGHT...CHANCE OF SHRA/MVFR LATE.
* WEDNESDAY...CHANCE OF SHRA. MVFR POSSIBLE EARLY.
* THURSDAY...VFR.
* FRIDAY...VFR. CHANCE OF SHRA FRIDAY NIGHT.
* SATURDAY...CHANCE OF SHRA/SLIGHT CHANCE OF TSRA.
* SUNDAY...VFR. CHANCE OF SHRA. CMS
&&
.MARINE...
317 AM...LOW PRESSURE OVER CENTRAL IL WILL LIFT NORTHEAST ACROSS
NORTHERN INDIANA TODAY REACHING LAKE ERIE TONIGHT. THERE COULD BE A
FEW HOUR PERIOD EARLY THIS MORNING WHERE WINDS OVER SOUTHERN LAKE
MICHIGAN GUST INTO THE 15-25 KT RANGE AS THE LOW APPROACHES WITH A
SOUTHEAST DIRECTION SHIFTING TO THE NORTHEAST THIS MORNING. WINDS
WILL THEN SHIFT NORTHERLY AND DIMINISH INTO THE 10-15 KT RANGE
THIS AFTERNOON. A WEAK RIDGE MAY ALLOW WINDS TO DIMINISH EVEN
FURTHER ALONG THE WESTERN SIDE OF THE LAKE. A SECOND LOW WILL MOVE
SOUTHEAST ACROSS THE NORTHERN LAKES TONIGHT AND MERGE WITH THE
FIRST LOW LIFTING NORTHEAST ACROSS THE EASTERN LAKES ON TUESDAY. A
COLD FRONT WILL THEN MOVE SOUTH ACROSS THE LAKE TUESDAY NIGHT INTO
WEDNESDAY MORNING WITH NORTHERLY WINDS POSSIBLY INCREASING TO
15-25 KT. A LARGE RIDGE OF HIGH PRESSURE WILL THEN BUILD EAST
ACROSS THE LAKES REGION WEDNESDAY NIGHT INTO THURSDAY. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
743 PM EDT TUE MAY 8 2012
.AVIATION...
VFR CONDITIONS THIS EVENING AND OVERNIGHT. MID LEVEL CLOUDS WILL
INCREASE THROUGH THE EVENING AS UPPER LOW AND SURFACE TROUGH
APPROACH. MODELS INDICATING INCREASE IN LOW LEVEL RH WEDNESDAY
MORNING WHICH SHOULD YIELD MVFR CIGS. VERY COLD AIR ALOFT WITH UPPER
LOW SO INSTABILITY SHOWERS WILL LIKELY DEVELOP. COVERAGE IN QUESTION
AND SOME SHORT TERM HI RES GUIDANCE SUGGEST DEVELOPMENT COULD BE
LIGHT AND SOUTH AND EAST OF TERMINALS. KEPT MENTION OUT OF TAFS FOR
NOW GIVEN OUTSIDE 12 HOUR WINDOW AND THE UNCERTAINTY. COULD BE
ISOLATED THUNDER ALSO AND CLOSER TO KFWA BUT AGAIN THE LOW PROB
NATURE DOES NOT WARRANT INCLUSION AT THIS TIME RANGE.
&&
.SHORT TERM...
TONIGHT...WEDNESDAY...WEDNESDAY NIGHT...
WATER VAPOR IMAGERY AND LATEST RUC ANALYSIS CLEARLY DEPICTING THE
MAIN FEATURE OF CONCERN IN THE SHORT TERM...DEEP UPPER TROUGH OVER
MN THAT WILL BE DROPPING DOWN ACROSS THE GREAT LAKES REGION TONIGHT
AND WEDNESDAY. AHEAD OF THIS FEATURE WILL BE AN INCREASING SFC
GRADIENT ALONG WITH DRIER AIR IN THE BOUNDARY LAYER AND LOW LEVELS
WHICH SHOULD PRECLUDE ANY SIGNIFICANT FOG REDEVELOPMENT. 12Z RAOBS
SHOWING -25C COLD POOL TO ACCOMPANY TROUGH AND RESULT IN VERY STEEP
MID LEVEL LAPSE RATES BY THE LATE MORNING HOURS. EXPECT THE
DIURNALLY DRIVEN SHRA AND EVEN A FEW TSRA CURRENTLY SEEN OVER MN AND
WI WILL SPREAD OVER THE GREAT LAKES REGION AFTER MIDNIGHT TONIGHT
AND WEDNESDAY. WILL USE THE TRACK OF UPPER TROUGH AND COLD POOL IN
TIMING OF PRECIP CHANCES...BEGINNING IN THE NW CWA AFTER MIDNIGHT
TONIGHT AND CONTINUING IN THE EASTERN HALF THROUGH WEDNESDAY AFTN.
MAGNITUDE OF COLD POOL WILL ALSO FAVOR CONVECTIVE POTENTIAL BY THE
AFTERNOON HOURS...BUFKIT SOUNDINGS SHOWING TT GT 50...SO WILL ALSO
INCLUDE A MENTION OF THUNDER HERE. RESULTING TEMPS WILL BE
CONSIDERABLY COOLER IN THIS PATTERN...5-10F BELOW NORMAL BOTH
WEDNESDAY AND WEDNESDAY NIGHT.
&&
.LONG TERM...
MEAN TROUGHING WILL REDVLP ACRS THE NE CONUS INTO THIS WEEKEND AS
WRN RIDGING AMPLIFIES. THUS W/PATTN REORIENTING TWD YET ANOTHER
PNA...XPC DRY WX TO CONT AS W/NW FLW ALOFT CONTS AND LL RIDGING
PERSISTS ACRS THE GOMEX W/LTL IN WAY OF SIG LL MSTR RTN UNTIL PSBLY
AT THE END OF THE PD ON DY8. TEMPS THROUGH THE PD GENERALLY NR
NORMAL.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SHORT TERM...LOGSDON
LONG TERM...T
AVIATION...LASHLEY
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
347 PM EDT MON MAY 7 2012
.SHORT TERM...
TONIGHT...TUESDAY...TUESDAY NIGHT...
CONVECTIVE REDEVELOPMENT NOT FULLY MATERIALIZING YET AS AIRMASS
STRUGGLES TO RECOVER FROM EARLIER RAINS. KIWX RADAR SHOWING LONE
CONVECTIVE CELL JUST SOUTH OF THE CWA NEAR MUNCIE. KIND RADAR
INDICATING ADDL DEVELOPMENT NOW BEGINNING TO TAKE SHAPE FURTHER
SOUTH. WATER VAPOR IMAGERY AND LATEST RUC ANALYSIS SHOWING WEAK
SHORT WAVE APPROACHING THE AREA SO STILL HOLDING OUT HOPE FOR MORE
ORGANIZED PRECIP THIS EVENING AS SFC LOW AND FRONTAL BOUNDARY
CONTINUE TO MOVE EASTWARD...BUT HAVE DROPPED POPS OVER THE EASTERN
CWA AND OPTED FOR SCT WORDING. WILL KEEP MENTION OF THUNDER IN THE
SE CWA AS LATEST LAPS DATA ALONG WITH SPC MESO ANALYSIS HAS CAPES
NUDGING UP OVER 1000J/KG INTO JAY COUNTY. VIS SAT ALSO SHOWING
CLOUDS THINNING OUT FROM MARION TO LIMA SO FURTHER LATE AFTN
DESTABILIZATION EXPECTED. 12Z MODELS A LITTLE SLOWER IN MOVING
SYSTEM OUT SO WILL HANG ON TO SMALL CHANCE IN SE CWA TILL 12Z TUE.
REST OF THE SHORT TERM WILL FEATURE CAA PATTERN AS UPPER LOW DROPS
INTO THE NORTHERN GREAT LAKES. SHOULD STILL GET TO AROUND NORMAL FOR
HIGHS TUESDAY AS 850MB THERMAL TROUGH DELAYED UNTIL TUE NITE/WED AM.
EXPECT AN INCREASE IN CLOUD COVER TUE NITE AS UPPER TROUGH SINKS
FURTHER SOUTH ALONG WITH SECONDARY COLD FRONT.
&&
.LONG TERM...WEDNESDAY THROUGH MONDAY
AN UPPER LEVEL SPEED MAX DIGGING SOUTHWARD ACROSS THE UPPER MIDWEST
AND UPPER MS VALLEY WILL ALLOW UPPER TROUGH TO SHIFT SOUTHEAST INTO
THE GREAT LAKES REGION BY WEDNESDAY MORNING. MOISTURE WILL BE
RELATIVELY UNIMPRESSIVE WITH THIS SYSTEM AND THUS MAIN PRECIP CHANCE
IS EXPECTED TO BE CONFINED TO ASSOCIATED WEAK LOW LEVEL CONVERGENCE
AXIS THAT WILL BE DROPPING SOUTHWARD ACROSS THE AREA ON WEDNESDAY.
MID LEVEL COLD POOL IS EXPECTED TO SHIFT SOUTHEAST ACROSS LOWER
MICHIGAN INTO WEDNESDAY NIGHT. SOME WEAK SFC BASED INSTABILITY IS
POSSIBLE ON WEDNESDAY AFTERNOON ESPECIALLY ACROSS NORTHEAST PORTIONS
OF THE FORECAST AREA CLOSER TO THESE COOLER MID LEVEL PROFILES. WILL
HOLD OFF ON ANY TS INCLUSION AT THIS POINT WITH SOME CONCERN THAT IF
SOME DEEPER MIXING IS REALIZED...THIS COULD LIMIT ANY SFC BASED
INSTABILITY. CHANCE OF PRECIP TO COME TO AN END WEDNESDAY EVENING AS
THIS UPPER TROUGH SHIFTS EAST. BROAD LOW LEVEL ANTICYCLONE WILL THEN
OVERSPREAD THE REGION FOR THURSDAY AND FRIDAY SETTING UP A FEW QUIET
DAYS TO END THE WEEK.
LOW LEVEL ANTICYCLONE WILL BE VERY SLOW TO SHIFT EAST AS UPPER RIDGE
TO THE WEST AMPLIFIES AS IT APPROACHES THE GREAT LAKES REGION FRIDAY
IN RESPONSE TO NEXT PROGRESSIVE EASTERN PACIFIC TROUGH TRACKING INTO
THE NORTHERN PLAINS. MOISTURE RETURN IN ADVANCE OF THIS PACIFIC
TROUGH WILL BE SOMEWHAT ROUNDABOUT DUE TO PRESENCE OF DEPARTING
ANTICYCLONE TO THE SOUTHEAST. THIS SHOULD CONFINE ANY LOW LEVEL
MOISTURE RETURN OF CONSEQUENCE TO A FAIRLY NARROW CORRIDOR IN
ADVANCE OF ASSOCIATED COLD FRONTAL BOUNDARY. WHILE SOME SLIGHT
TIMING DIFFERENCES PERSIST WITH THIS FRONT...CHARACTERISTIC OF LARGE
SCALE FLOW AND GOOD AGREEMENT AMONGST MEDIUM RANGE MODELS HANDLING
THIS NEXT EASTERN PACIFIC TROUGH STILL LEND ENOUGH CONFIDENCE TO
MAINTAIN LOW CHANCE POPS FOR FRIDAY NIGHT INTO SUNDAY. ONCE FRONTAL
TIMING BECOMES BETTER RESOLVED WILL LIKELY BE ABLE TO CONTRACT THE
DURATION OF THESE POPS. HAVE OMITTED THUNDER AT THIS TIME GIVEN SOME
UNCERTAINTIES AS TO EXTENT OF LOW LEVEL MOISTURE RETURN BUT THIS
WILL ALSO NEED TO BE REASSESSED IN LATER FORECASTS. SOME SLIGHT
MODERATION IN TEMPERATURES EXPECTED FOR FRIDAY IN ADVANCE OF THIS
FRONT...BUT OVERALL TEMPERATURES NEAR SEASONABLE LEVELS ARE EXPECTED
THROUGH THE PERIOD. A RETURN TO DRY CONDITIONS EXPECTED FOR EARLY
NEXT WEEK AS THIS SYSTEM DEPARTS TO THE EAST.
&&
.AVIATION...
KIWX RADAR SHOWING MAJORITY OF PRECIP OUT OF THE CWA ATTM LEAVING
JUST SCATTERED SHOWERS OVER THE AREA TO BEGIN TAF PERIOD. SFC LOW
SLOWING MOVING ACROSS THE AREA AS REDEVELOPING SHOWERS OVER ILLINOIS
EXPECTED TO MOVE ACROSS BOTH TAF SITES LATE THIS AFTERNOON/EARLY
EVENING. AMPLE LOW LEVEL MOISTURE FROM EARLIER RAINS HAS IFR
CONDITIONS IN AND AROUND BOTH TAF SITES. CIGS SHOULD IMPROVE
SLIGHTLY AS PRECIP MOVES IN BUT THEN EXPECT MVFR CIGS TO REMAIN OVER
THE AREA OVERNIGHT BEFORE DRIER AIR FINALLY BEGINS TO WORK INTO THE
AREA BY EARLY TUESDAY MORNING. MID LEVEL DRYING AND WEAK SFC FLOW
SHOULD ALSO ALLOW FOR MVFR VSBYS AT BOTH TAF SITES WITH FOG
DEVELOPMENT LATER TONIGHT.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SHORT TERM...LOGSDON
LONG TERM...MARSILI
AVIATION...LOGSDON
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
145 AM EDT MON MAY 7 2012
.AVIATION.../06Z TAFS/
STRONG LOW LEVEL THETA-E ADVECTION CAUSING MCS DEVELOPMENT OVER NW
INDIANA/NRN IL EARLY THIS MORNING. 00Z NAM12 APPEARS TO BE TOO WK
WITH LLJ AND TOO FAR NE. EXPECT TSRA WILL CONT TO IMPACT SBN MUCH
OF THE NGT AS CONVECTION SHIFTS SLOWLY ENE WITH TS LIKELY
IMPACTING FWA AFT 08Z. ANOTHER ROUND OF TS PSBL DURING THE
DAY AS CDFNT MOVES THROUGH THE AREA BUT LEFT OUT OF TAFS FOR NOW
DUE TO CONCERN THAT DESTABILIZATION WILL BE HINDERED BY MORNING
CONVECTION. MVFR CONDITIONS IN TS OVERNIGHT SHOULD BECOME
WIDESPREAD BY MORNING AS LOW LEVELS MOISTEN UP. WINDS WILL SHIFT TO
NW BEHIND THE FRONT AS IT MOVES SLOWLY EAST ACROSS THE AREA TODAY
WITH VFR CONDITIONS EXPECTED ACROSS THE AREA BY THIS EVE.
&&
.PREV DISCUSSION... /ISSUED 1203 AM EDT MON MAY 7 2012/
UPDATE...
ZONES/GRIDS UPDATED TO REFLECT CURRENT RADAR TRENDS AND TRENDS OF
LATEST HRRR MODELS.
CONVECTION HAS BEEN RAPIDLY DEVELOPING OVER THE PAST FEW HOURS
ACROSS PORTIONS OF SOUTHERN LAKE MI INTO N ILLINOIS IN AREA OF
MODERATE INSTABILITY AND NUMEROUS OUTFLOW BOUNDARIES. A FEW
SHOWERS AND STORMS HAVE DEVELOPED ACROSS LAPORTE AND BERRIEN
COUNTIES AND ARE TRYING TO MOVE EAST. HOWEVER...LARGE SFC DEWPT
GRADIENT NOTED WITH MUCH OF THE NE PARTS OF THE CWA SEEING DEWPTS
IN THE 30S AND 40S VS READINGS IN THE UPEPR 50S TO LOWER 60S ALONG
THE WESTERN TIER OF COUNTIES. HRRR PICKED UP ON THIS FEATURE AND
HOLDS WITH THESE LOWER SFC DEWPTS THROUGH THE NIGHT. HOWEVER...LL
MSTR ADVECTION CONTINUES TO INCREASE WHICH ALLOWS FOR AT LEAST AN
SLOW UPSWING IN SHOWER TRENDS. HAVE ADJUSTED GRIDS TO REFLECT
SLOWER ARRIVAL OF HIGHER POPS FROM WEST TO EAST THROUGH THE
REMAINDER OF THE NIGHT. THREW IN MENTION OF HEAVY RAIN GIVEN
INCREASING PWATS AND SLOW FLOW TO ALLOW FOR BACKBUILDING AND SLOW
FORWARD PROPAGATION.
PREV DISCUSSION... /ISSUED 354 PM EDT SUN MAY 6 2012/
SHORT TERM... / LATE THIS AFTERNOON THROUGH MONDAY NIGHT /
MAIN CONCERN THIS PERIOD REMAINS CHANCES FOR CONVECTION.
SYNOPTICALLY...A CLOSED UPPER LOW OVER SOUTHERN SASKATCHEWAN WILL
TRACK EWD TOWARD THE NORTH DAKOTA/MANITOBA BORDER...WITH A TRAILING
POSITIVELY TILTED H5 TROUGH DROPPING INTO THE NORTH-CENTRAL CONUS.
AT THE SFC AS OF 19Z THERE WAS A QUASI STATIONARY FRONT DRAPED SW OF
THE FA FROM CENTRAL IL WEST TO A WEAK SFC REFLECTION NEAR KANSAS
CITY. AN OCCLUDED FRONT EXTENDED NORTH FROM HERE INTO THE UPPER
MIDWEST. THESE FRONTAL BOUNDARIES AND SFC REFLECTION WILL LIKELY
CONVERGE OVER THE LOCAL AREA TOMORROW. THIS WILL BRING INCREASING
CHANCES FOR SHOWERS AND STORMS TO THE AREA TONIGHT INTO TOMORROW.
LATE THIS AFTN INTO EARLY THIS EVENING...MCV ACROSS WISCONSIN WILL
WORK INTO CENTRAL AND NORTHERN PORTIONS OF MICHIGAN. SHOWERS
ASSOCIATED WITH THIS FEATURE HAVE WEAKENED ACROSS OUR FAR NW THIS
AFTN AS THEY ENCOUNTERED MUCH MORE STABLE AIR. RAISED POPS IN THE
FAR NW TO ACCOUNT FOR THESE WEAKENING SHOWERS WITH ONLY LIGHT
AMOUNTS EXPECTED OVER THE NEXT SEVERAL HOURS. FARTHER WEST ACROSS
NRN IL AND NRN MO SCT CONVECTION HAS FIRED ALONG A RATHER
IMPRESSIVE INSTABILITY GRADIENT. LATEST HI-RES GUIDANCE SUGGESTS
THAT COVERAGE WILL CONTINUE TO INCREASE INTO A MORE ORGANIZED
CONVECTIVE SYSTEM...MAINLY IMPACTING AREAS WEST INTO
CENTRAL/NORTHERN IL INTO THE EARLY EVENING HOURS. HOWEVER...COULD
SEE A FEW ELEVATED CELLS WORK INTO OUR WESTERN ZONES EARLY THIS
EVENING. OPTED TO CONTINUE WITH 30-60 POPS ACROSS MAINLY WESTERN
ZONES AFTER 00Z TO ACCOUNT FOR THIS...WITH A SLIGHT RISK FOR LARGE
HAIL AS MORE UNSTABLE AIR ADVECTS NEWD IN A WARM ADVECTION REGIME.
TONIGHT INTO MONDAY...LOW TO MID LEVEL THETA-E ADVECTION
EXPECTED AHEAD OF THE SFC LOW AND SFC INSTABILITY GRADIENT WILL
SUPPORT INCREASING CHANCES FOR SHOWERS/STORMS. COULD SEE SOME
LOCALLY HEAVY RAINFALL GIVEN EXPECTED SLOW MOVEMENT AND PWATS
INCREASING TO NEAR 1.6 INCHES. NO CHANGES TO INHERITED LIKELY POPS
INTO MONDAY AFTERNOON AS A MODEL CONSENSUS TRACKS THE AFOREMENTIONED
WEAK SFC LOW AND SOME SEMBLANCE OF A CONVECTIVELY ENHANCED/INDUCED
MID LEVEL PERTURBATION INTO NORTHERN INDIANA. THIS TRACK WOULD BRING
THE WARM FRONT AND MOIST/UNSTABLE BOUNDARY LAYER AIR INTO OUR
SOUTHEASTERN ZONES...WHICH BRINGS ABOUT THE CONCERN FOR SEVERE SFC
BASED CONVECTION HERE BY MONDAY AFTN. VERY LOW CONFIDENCE HERE GIVEN
EXPECTED LEFTOVER CLOUD COVER AND SHOWERS...WITH A MORNING MCS
OUTFLOW POSSIBLY FORCING THE FRONTAL BOUNDARY/SFC WAVE FARTHER
SOUTH. ISOLATED WIND DAMAGE/LARGE HAIL WILL BE THE PRIMARY THREAT IF
THESE AREAS ARE ABLE TO RECOVER THERMODYNAMICALLY...WITH MULTICELLS
POSSIBLE IN A WEAKLY SHEARED ENVIRONMENT.
LONG TERM...TUESDAY THROUGH SUNDAY
STRONG COLD ADVECTION TO BEGIN THIS PERIOD AS COLD FRONTAL ZONE
CONTINUES TO SHIFT EASTWARD FROM THE GREAT LAKES REGION INTO THE
LOWER OHIO VALLEY. POST FRONTAL DRY AIR ADVECTION WILL ALSO RESULT
IN MOSTLY SUNNY SKIES BY TUESDAY AFTERNOON. DESPITE COLD
ADVECTION...BOUNDARY LAYER WILL BE RELATIVELY DEEP AND BETTER LOW
LEVEL MIXING SHOULD SUPPORT HIGHS FROM MID TO UPPER 60S NORTH TO THE
LOWER 70S SOUTH.
FOR TUESDAY NIGHT...BLOCKING PATTERN ACROSS EASTERN CANADA WILL
RESULT IN SOUTHEAST MIGRATION OF UPPER LEVEL TROUGH CURRENTLY
APPROACHING THE NORTHERN HIGH PLAINS. PRECEDING DRY AIR ADVECTION
WILL MAKE PRECIP POTENTIAL QUESTIONABLE WITH THIS UPPER TROUGH.
POSITIVELY TILTED NATURE OF THIS TROUGH AS IT DROPS SOUTHWARD ACROSS
THE WESTERN GREAT LAKES SHOULD CONFINE PRECIP POTENTIAL TO
IMMEDIATELY DOWNSTREAM OF TROUGH AXIS ACROSS NORTHWEST PORTIONS OF
CWA TUESDAY NIGHT...CLOSER TO ASSOCIATED WEAK LOW LEVEL CONVERGENCE
AXIS. FURTHER DOWNSTREAM ACROSS NORTHEAST INDIANA INTO NORTHWEST
OHIO LOW LEVEL MOISTURE PROFILES WILL LIKELY REMAIN MORE MEAGER AND
HAVE REMOVED POPS TUESDAY NIGHT ACROSS THE EAST. HAVE MAINTAINED
CHANCE POPS ON WEDNESDAY AS UPPER TROUGH DIGS SOUTHEAST ACROSS THE
SOUTHERN GREAT LAKES BUT PRECIP AMOUNTS SHOULD BE ON THE LIGHT SIDE.
DRY CONDITIONS FOR WEDNESDAY NIGHT/THURSDAY AS THIS UPPER TROUGH
DEPARTS TO THE EAST AS MID/UPPER LEVEL HEIGHT RISES OVERSPREAD UPPER
MIDWEST AND GREAT LAKES REGION. SLOW MODERATION IN TEMPERATURES BACK
CLOSE TO NORMAL EXPECTED TOWARD THE END OF THE WEEK AS BROAD 1020 MB
SFC ANTICYCLONE SHIFTS INTO THE MID ATLANTIC STATES. ATTENTION FOR
THE REMAINDER OF THE PERIOD WILL FOCUS ON NEXT FAST MOVING PACIFIC
WAVE EXPECTED TO TRACK ACROSS NORTHERN CONUS/SOUTH CENTRAL CANADA
THIS WEEKEND. NARROW CORRIDOR OF MOISTURE RETURN IS POSSIBLE JUST IN
ADVANCE OF THIS FRONT BUT WILL INTRODUCE ONLY LOW CHANCE SHRA
MENTION AT THIS TIME WITH STRONGEST LOW LEVEL CONVG EXPECTED TO
REMAIN TO THE NORTH. WITH STRONGER FORCING AND MORE PROGRESSIVE FLOW
LIKELY REMAINING ACROSS GREAT LAKES INTO SOUTHEAST CANADA...THIS
BOUNDARY MAY STALL OUT ACROSS THE SOUTHERN GREAT LAKES TOWARD THE
END OF THE PERIOD...AND THUS HAVE MAINTAINED LOW CHANCE POPS INTO
SUNDAY.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SHORT TERM...STEINWEDEL
LONG TERM...MARSILI
AVIATION...JT
AREA FORECAST DISCUSSION
NWS JACKSON KY
327 PM EDT MON MAY 7 2012
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 327 PM EDT MON MAY 7 2012
SCATTERED CONVECTION CONTINUES TO FIRE UP MAINLY ALONG AND SOUTH OF
THE HAL ROGERS PARKWAY AND HIGHWAY 80 CORRIDORS. THE RADAR REMAINS
PRETTY QUIET OFF TO THE WEST AND DESPITE THE HRRR INSISTENCE UPON
CONVECTION GETTING GOING IN WESTERN KENTUCKY AND TRANSLATING
EASTWARD...ITS HARD TO SEE ANYTHING ORGANIZED HITTING THE AREA
THROUGH AT LEAST EARLY THIS EVENING.
THE MODELS HAVE DECISIVELY SPED UP THE TIMING OF THE SURFACE AND
UPPER LEVEL FEATURES ON THE 12Z RUNS THROUGH THE SHORT TERM. AS
SUCH...HAVE EXITED EVERYTHING A BIT FASTER...ALTHOUGH AM HESITANT TO
BE TOO AGGRESSIVE AS THIS HAS NOT BEEN TREND WITH THIS SYSTEM LATELY.
SCATTERED CONVECTION SHOULD CONTINUE THROUGH EARLY THIS EVENING...AND
THEN WILL WIND DOWN TEMPORARILY WITH THE LOSS OF HEATING. MID-LEVEL
LAPSE RATES AND RADAR TRENDS CONTINUE TO UN-IMPRESS...SO WOULD BE
SURPRISED IF ANY STORMS BECOME THAT INTENSE. STILL...WILL HANG ONTO
AN ISOLATED SEVERE WORDING IN THE HWO THROUGH DUSK.
THE COLD FRONT AND BETTER MID-LEVEL FORCING WILL NUDGE TOWARDS THE
AREA LATER TONIGHT INTO EARLY TUESDAY MORNING...ALLOWING FOR MORE
WIDESPREAD PRECIPITATION COVERAGE. DEEPER MOISTURE WILL THEN
GRADUALLY EXIT DURING THE DAY ON TUESDAY...WITH SHOWERS DIMINISHING
FROM NORTHWEST TO SOUTHEAST INTO TUESDAY EVENING.
THE MAIN TROUGH AXIS WILL SHIFT THROUGH THE AREA ON WEDNESDAY...WITH
PERHAPS ENOUGH MOISTURE TO ALLOW FOR A FEW SHOWERS...ESPECIALLY ALONG
AND NORTH OF THE MOUNTAIN PARKWAY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 327 PM EDT MON MAY 7 2012
THE MODELS ARE IN PRETTY GOOD AGREEMENT AT THE START OF THE EXTENDED
WITH A FAIRLY DEEP TROUGH CROSSING THE OHIO VALLEY AND A NEARLY
DISCONNECTED LOW MEANDERING OVER NORTHERN OLD MEXICO. THE TROUGH
WILL SWEEP THROUGH THE AREA WEDNESDAY NIGHT WITH SIMILAR TIMING AND
STRENGTH IN ALL MODELS...THOUGH THE ECMWF AND GFS DO SYNCH UP THE
BEST. ONCE THE AXIS GOES THROUGH EAST KENTUCKY...A NODE OF THE UPPER
LOW RESPONSIBLE WILL PIVOT THROUGH THE GREAT LAKES AND PASS BY TO
OUR NORTHEAST DURING THE DAY THURSDAY MARKING THE LAST OF THE LOWER
HEIGHTS FROM THIS SYSTEM. BROAD RIDGING THEN COMMENCES THROUGH THE
END OF THE WEEK AND START OF THE WEEKEND. THIS WILL BE IN RESPONSE
TO THE SLOW APPROACH OF THE LOST UPPER LOW TO THE SOUTHWEST. THE
REMAINS OF THIS LOW WILL DRIFT EAST THROUGH THE SOUTHERN PLAINS AND
RELEASE ITS WEAK ENERGY EAST INTO THE OHIO AND TENNESSEE VALLEYS FOR
MAINLY THE LATTER PART OF THIS WEEKEND. AT THE SAME TIME...ANOTHER
TROUGH WILL BE PUSHING SOUTH INTO THE NORTH PLAINS AND EVENTUALLY
INTO THE NORTHERN OHIO VALLEY ON SUNDAY. WEAK WAVES IN THE SOUTHERN
STREAM WILL PASS THROUGH THE BASE OF THIS TROUGH AND POTENTIALLY
AFFECT KENTUCKY HEADING INTO THE START OF THE NEW WORK WEEK. THE
MODELS BECOME INCREASINGLY MUDDLED WITH TIME SO THAT A BLEND IS THE
MOST SENSIBLE APPROACH FOR THE LATTER PARTS OF THE EXTENDED...WHILE
FOR THE BEGINNING THE ECMWF WAS PREFERRED.
SENSIBLE WEATHER WILL FEATURE THE SLOW DEPARTURE OF THE STALLED
FRONT JUST TO OUR EAST ON WEDNESDAY NIGHT...THOUGH A COUPLE OF
EVENING SHOWERS MAY LINGER IN FAR EASTERN PARTS OF KENTUCKY. THE
TROUGH AXIS PASSING THROUGH BY MIDDAY THURSDAY MAY GEN UP A FEW
BONUS SHOWERS...BUT FOR NOW HAVE LEFT IT DRY. COOL AND DRY HIGH
PRESSURE THEN PUSHES INTO THE REGION AND WILL KEEP THE WEATHER
SETTLED AND PLEASANT THROUGH THE START OF THE WEEKEND. THIS HIGH
MODERATES AND MOVES EAST BY LATE SATURDAY ALLOWING MORE MOISTURE AND
WARMTH TO RETURN TO EAST KENTUCKY. FOR SUNDAY THROUGH MONDAY...WEAK
LOW PRESSURE TO THE SOUTH...A NEW COLD FRONT STALLING TO THE NORTH
AND AMPLE MOISTURE IN PLACE SHOULD BE ENOUGH TO GENERATE MAINLY
DIURNALLY DRIVEN SCATTERED CONVECTION FOR THE END OF THE EXTENDED AS
A MORE NORMAL LATE SPRING/EARLY SUMMER PATTERN TAKES HOLD.
THE GRID LOAD CAME IN RATHER NICE...THOUGH DID NUDGE POPS DOWN
FOR MOST OF THE CWA FROM THURSDAY THROUGH SATURDAY. ALSO...ADDED THE
STANDARD TERRAIN DRIVEN DETAILS TO THE LOW TEMPERATURE GRIDS EACH
NIGHT FROM THURSDAY THROUGH SATURDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 206 PM EDT MON MAY 7 2012
SCATTERED SHOWERS AND THUNDERSTORMS WILL BE PREVALENT ACROSS EASTERN
KENTUCKY THROUGH THIS AFTERNOON. SOME OF THESE WILL COME PRETTY CLOSE
TO TERMINALS...HOWEVER HAVE CHOSEN TO STICK WITH VCTS FOR NOW.
BETTER COVERAGE OF SHOWERS AND THUNDERSTORMS WILL ARRIVE THIS EVENING
AND TONIGHT...WITH CEILINGS DROPPING BACK TO MVFR LATE TONIGHT INTO
TUESDAY MORNING...AND THEN EVEN IFR BY THE MID-MORNING HOURS ON
TUESDAY AS A COLD FRONT GRADUALLY MOVES THROUGH THE AREA.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GEOGERIAN
LONG TERM....GREIF
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS JACKSON KY
206 PM EDT MON MAY 7 2012
.UPDATE...
ISSUED AT 206 PM EDT MON MAY 7 2012
CONVECTION HAS STARTED TO FIRE UP...MAINLY ALONG AND SOUTH OF THE HAL
ROGERS PARKWAY AND HIGHWAY 80. THE LATEST MESO-ANALYSIS PAGE SHOWS
MID-LEVEL LAPSE RATES REMAINING PRETTY WEAK...SO THE SEVERE THREAT IS
LOWER...HOWEVER CAN NOT COMPLETELY RULE OUT AN ISOLATED ONE OR TWO
WITH SOME STORM INTERACTION SO WILL LEAVE THIS MENTION IN THE HWO FOR
NOW. MAINLY FRESHENED UP THE HOURLY TEMPERATURES AND DEW POINTS TO
BETTER MATCH OBSERVATIONAL TRENDS.
UPDATE ISSUED AT 1056 AM EDT MON MAY 7 2012
THE MODELS CONTINUE TO DIFFER ON HOW MUCH AREAL CONVECTIVE COVERAGE
WE WILL REALLY SEE TODAY. THE LATEST NAM HAS VERY LITTLE IF ANY
THROUGH 00Z...ALONG WITH THE SREF. THE HRRR SHOWS AT LEAST SCATTERED
IF NOT NUMEROUS COVERAGE AT TIMES. THE CURRENT VISIBLE SATELLITE DOES
REVEAL AN OUTFLOW BOUNDARY MOVING EAST THROUGH CENTRAL KENTUCKY...
POISED TO MOVE THROUGH EASTERN KENTUCKY THIS AFTERNOON CLOSER TO PEAK
HEATING. WHILE THIS FEATURE WILL LIKELY WEAKEN WITH TIME...IT COULD
PROVIDE ENOUGH OF A WEAKNESS IN THE CAP TO GET CONVECTION GOING. AS
SUCH...DECIDED TO RAISE POPS SOMEWHAT FURTHER EAST. THE ATMOSPHERE IS
MODERATELY UNSTABLE...SO A FEW STORMS COULD APPROACH SEVERE LIMITS...
ESPECIALLY IF SOME STORM INTERACTION CAN TAKE PLACE.
UPDATE ISSUED AT 750 AM EDT MON MAY 7 2012
UPDATED THE FORECAST TO REFLECT CURRENT CONDITIONS AND MODEL TRENDS.
ONLY MADE SOME MINOR ADJUSTMENTS TO THE TEMPERATURES...WINDS AND DEW
POINTS.
UPDATE ISSUED AT 455 AM EDT MON MAY 7 2012
UPDATED THE FORECAST TO REFLECT CURRENT CONDITIONS AND MODEL TRENDS.
ONLY MADE SOME MINOR ADJUSTMENTS TO THE TEMPERATURES AND DEW POINTS.
NO ZONE UPDATE WILL BE REQUIRED.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 301 AM EDT MON MAY 7 2012
THE MODELS ARE IN DECENT AGREEMENT WITH THE TIMING OF THIS NEXT
SYSTEM. THE TIMING OF THE ACTUAL FRONT MOVING THROUGH HAS BEEN SLIPPING
OVER THE LAST FEW MODEL RUNS. THE MODELS ARE ALL VERY SLOW TO
ACTUALLY PUSH THIS SYSTEM THROUGH THE AREA. CONSIDERING THE GOOD
MODEL AGREEMENT...CONFIDENCE IS HIGHER THAN NORMAL. THE BIG
QUESTION FOR THIS AFTERNOON IS WHETHER OR NOT THERE WILL BE ANY
TRIGGERS TO GET SOME THUNDERSTORMS POPPING. ALL THE MODELS ARE NOW
GENERATING PRECIPITATION OVER THE AREA...HOWEVER THERE IS A LACK OF ANY
WELL DEFINED TRIGGERS. ONCE ANY CELLS DEVELOP AND THERE ARE ANY
OUTFLOWS...THEN THE VERY UNSTABLE AIR WILL ALLOW FOR THUNDERSTORMS TO
KEEP GOING FOR A WHILE. THESE WILL BE PULSE TYPE THUNDERSTORMS THAT DO
NOT MOVE VERY FAST. AS SUCH...THERE MAY BE SOME ISSUES WITH NUISANCE
TYPE FLOODING WITH DITCHES AND LOW WATER CROSSINGS RUNNING FULL. THE
PRECIPITABLE WATER WILL BE ABOUT 1.41 INCHES...SO RAINFALL RATES OF
OVER 1 INCH PER HOUR WILL BE FAIRLY EASY TO OBTAIN. THE MAJOR FORCING
WOULD APPEAR TO BE MOVING ACROSS THE AREA AFTER MIDNIGHT. BACK END OF
THE SYSTEM WILL NOT BE MOVING THROUGH THE AREA WEDNESDAY AFTERNOON.
EXPECT THE RAIN TO CONTINUE OFF AND ON THROUGH TUESDAY. FOR
TEMPERATURES...KEPT PRETTY CLOSE TO THE MOS BLEND. THE HIGHS FOR
TODAY MAY BE TOO HIGH IF THE CONVECTION INITIATES BEFORE NOON AND
CAUSES A LOT OF CLOUD COVER BEFORE PEAK HEATING.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 329 AM EDT MON MAY 7 2012
MODELS REMAIN IN REMARKABLY GOOD AGREEMENT THROUGH THE PERIOD
BOOSTING CONFIDENCE WITH THE FORECAST THROUGH THE END OF THE WEEK.
WE BEGIN TUESDAY NIGHT WITH LINGERING POST FRONTAL SHOWERS AND A FEW
THUNDERSTORMS OVER ERN KY AS THE UPPER LEVEL TROF SLOWLY SWINGS
THROUGH THE GREAT LAKES. ON WEDNESDAY THE TROF CONTINUES PUSHING
THROUGH THE OHIO VALLEY WITH PRECIP GRADUALLY ENDING FROM WEST TO
EAST THROUGH THE DAY AS WELL. BY WEDNESDAY NIGHT...STRONG HIGH
PRESSURE OVER THE THE HEART OF NOAM IN CONCERT WITH A BUDDING NRN
STREAM RIDGE OVER THE SRN CANADIAN PLAINS DOWN THROUGH THE NRN
ROCKIES SHIFTS EAST AND WILL BEGIN A STRETCH OF DRY...QUIET WEATHER
WITH MODERATING TEMPERATURES THAT LOOKS TO CONTINUE THROUGH THE END
OF THE WEEK. TOWARDS THE TAIL END OF THE PERIOD...BOTH THE EURO AND
THE GFS BRING A WEAK COLD FRONT INTO THE OHIO VALLEY...A LITTLE
QUICKER IN THE GFS VERSION...AS A SRN STREAM TROF MIGRATES FROM TX
THROUGH THE GULF COAST STATES...OPENING UP A RETURN FLOW OF WARM...
MOIST GOMEX AIR INTO THE REGION. GIVEN THE GOOD AGREEMENT THIS FAR
OUT...WILL KEEP SOLID CHANCES FOR PRECIP FOR THE END OF THE PERIOD
AND INTO THE BEGINNING OF NEXT WEEK.
AS FOR TEMPERATURES...THE EXTENDED INITIALIZATION CAME IN WITH A
REASONABLE STARTING POINT...THOUGH DID KEEP SOME MINOR ELEVATION
BASED DIFFERENCES FOR THURSDAY AND FRIDAY NIGHTS WITH HIGH PRESSURE
MOVING IN OVERHEAD. ALSO GAVE A BOOST TO HIGHS ON FRIDAY GIVEN THE
EXPECTED CLEAR SKIES...AND TO LINE UP A LITTLE BETTER WITH
SURROUNDING OFFICES. THIS ESSENTIALLY RESULTED IN TEMPS RUNNING A
LITTLE BELOW NORMAL THROUGH THE WEEK BEFORE RETUNING TO MORE
CLIMATOLOGICAL NORMS FOR THE WEEKEND...WITH OVERNIGHT LOWS GENERALLY
FOLLOWING A SIMILAR TREND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 206 PM EDT MON MAY 7 2012
SCATTERED SHOWERS AND THUNDERSTORMS WILL BE PREVALENT ACROSS EASTERN
KENTUCKY THROUGH THIS AFTERNOON. SOME OF THESE WILL COME PRETTY CLOSE
TO TERMINALS...HOWEVER HAVE CHOSEN TO STICK WITH VCTS FOR NOW.
BETTER COVERAGE OF SHOWERS AND THUNDERSTORMS WILL ARRIVE THIS EVENING
AND TONIGHT...WITH CEILINGS DROPPING BACK TO MVFR LATE TONIGHT INTO
TUESDAY MORNING...AND THEN EVEN IFR BY THE MID-MORNING HOURS ON
TUESDAY AS A COLD FRONT GRADUALLY MOVES THROUGH THE AREA.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...JJ
LONG TERM....MB
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS JACKSON KY
1056 AM EDT MON MAY 7 2012
.UPDATE...
ISSUED AT 1056 AM EDT MON MAY 7 2012
THE MODELS CONTINUE TO DIFFER ON HOW MUCH AREAL CONVECTIVE COVERAGE
WE WILL REALLY SEE TODAY. THE LATEST NAM HAS VERY LITTLE IF ANY
THROUGH 00Z...ALONG WITH THE SREF. THE HRRR SHOWS AT LEAST SCATTERED
IF NOT NUMEROUS COVERAGE AT TIMES. THE CURRENT VISIBLE SATELLITE DOES
REVEAL AN OUTFLOW BOUNDARY MOVING EAST THROUGH CENTRAL KENTUCKY...
POISED TO MOVE THROUGH EASTERN KENTUCKY THIS AFTERNOON CLOSER TO PEAK
HEATING. WHILE THIS FEATURE WILL LIKELY WEAKEN WITH TIME...IT COULD
PROVIDE ENOUGH OF A WEAKNESS IN THE CAP TO GET CONVECTION GOING. AS
SUCH...DECIDED TO RAISE POPS SOMEWHAT FURTHER EAST. THE ATMOSPHERE IS
MODERATELY UNSTABLE...SO A FEW STORMS COULD APPROACH SEVERE LIMITS...
ESPECIALLY IF SOME STORM INTERACTION CAN TAKE PLACE.
UPDATE ISSUED AT 750 AM EDT MON MAY 7 2012
UPDATED THE FORECAST TO REFLECT CURRENT CONDITIONS AND MODEL TRENDS.
ONLY MADE SOME MINOR ADJUSTMENTS TO THE TEMPERATURES...WINDS AND DEW
POINTS.
UPDATE ISSUED AT 455 AM EDT MON MAY 7 2012
UPDATED THE FORECAST TO REFLECT CURRENT CONDITIONS AND MODEL TRENDS.
ONLY MADE SOME MINOR ADJUSTMENTS TO THE TEMPERATURES AND DEW POINTS.
NO ZONE UPDATE WILL BE REQUIRED.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 301 AM EDT MON MAY 7 2012
THE MODELS ARE IN DECENT AGREEMENT WITH THE TIMING OF THIS NEXT
SYSTEM. THE TIMING OF THE ACTUAL FRONT MOVING THROUGH HAS BEEN SLIPPING
OVER THE LAST FEW MODEL RUNS. THE MODELS ARE ALL VERY SLOW TO
ACTUALLY PUSH THIS SYSTEM THROUGH THE AREA. CONSIDERING THE GOOD
MODEL AGREEMENT...CONFIDENCE IS HIGHER THAN NORMAL. THE BIG
QUESTION FOR THIS AFTERNOON IS WHETHER OR NOT THERE WILL BE ANY
TRIGGERS TO GET SOME THUNDERSTORMS POPPING. ALL THE MODELS ARE NOW
GENERATING PRECIPITATION OVER THE AREA...HOWEVER THERE IS A LACK OF ANY
WELL DEFINED TRIGGERS. ONCE ANY CELLS DEVELOP AND THERE ARE ANY
OUTFLOWS...THEN THE VERY UNSTABLE AIR WILL ALLOW FOR THUNDERSTORMS TO
KEEP GOING FOR A WHILE. THESE WILL BE PULSE TYPE THUNDERSTORMS THAT DO
NOT MOVE VERY FAST. AS SUCH...THERE MAY BE SOME ISSUES WITH NUISANCE
TYPE FLOODING WITH DITCHES AND LOW WATER CROSSINGS RUNNING FULL. THE
PRECIPITABLE WATER WILL BE ABOUT 1.41 INCHES...SO RAINFALL RATES OF
OVER 1 INCH PER HOUR WILL BE FAIRLY EASY TO OBTAIN. THE MAJOR FORCING
WOULD APPEAR TO BE MOVING ACROSS THE AREA AFTER MIDNIGHT. BACK END OF
THE SYSTEM WILL NOT BE MOVING THROUGH THE AREA WEDNESDAY AFTERNOON.
EXPECT THE RAIN TO CONTINUE OFF AND ON THROUGH TUESDAY. FOR
TEMPERATURES...KEPT PRETTY CLOSE TO THE MOS BLEND. THE HIGHS FOR
TODAY MAY BE TOO HIGH IF THE CONVECTION INITIATES BEFORE NOON AND
CAUSES A LOT OF CLOUD COVER BEFORE PEAK HEATING.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 329 AM EDT MON MAY 7 2012
MODELS REMAIN IN REMARKABLY GOOD AGREEMENT THROUGH THE PERIOD
BOOSTING CONFIDENCE WITH THE FORECAST THROUGH THE END OF THE WEEK.
WE BEGIN TUESDAY NIGHT WITH LINGERING POST FRONTAL SHOWERS AND A FEW
THUNDERSTORMS OVER ERN KY AS THE UPPER LEVEL TROF SLOWLY SWINGS
THROUGH THE GREAT LAKES. ON WEDNESDAY THE TROF CONTINUES PUSHING
THROUGH THE OHIO VALLEY WITH PRECIP GRADUALLY ENDING FROM WEST TO
EAST THROUGH THE DAY AS WELL. BY WEDNESDAY NIGHT...STRONG HIGH
PRESSURE OVER THE THE HEART OF NOAM IN CONCERT WITH A BUDDING NRN
STREAM RIDGE OVER THE SRN CANADIAN PLAINS DOWN THROUGH THE NRN
ROCKIES SHIFTS EAST AND WILL BEGIN A STRETCH OF DRY...QUIET WEATHER
WITH MODERATING TEMPERATURES THAT LOOKS TO CONTINUE THROUGH THE END
OF THE WEEK. TOWARDS THE TAIL END OF THE PERIOD...BOTH THE EURO AND
THE GFS BRING A WEAK COLD FRONT INTO THE OHIO VALLEY...A LITTLE
QUICKER IN THE GFS VERSION...AS A SRN STREAM TROF MIGRATES FROM TX
THROUGH THE GULF COAST STATES...OPENING UP A RETURN FLOW OF WARM...
MOIST GOMEX AIR INTO THE REGION. GIVEN THE GOOD AGREEMENT THIS FAR
OUT...WILL KEEP SOLID CHANCES FOR PRECIP FOR THE END OF THE PERIOD
AND INTO THE BEGINNING OF NEXT WEEK.
AS FOR TEMPERATURES...THE EXTENDED INITIALIZATION CAME IN WITH A
REASONABLE STARTING POINT...THOUGH DID KEEP SOME MINOR ELEVATION
BASED DIFFERENCES FOR THURSDAY AND FRIDAY NIGHTS WITH HIGH PRESSURE
MOVING IN OVERHEAD. ALSO GAVE A BOOST TO HIGHS ON FRIDAY GIVEN THE
EXPECTED CLEAR SKIES...AND TO LINE UP A LITTLE BETTER WITH
SURROUNDING OFFICES. THIS ESSENTIALLY RESULTED IN TEMPS RUNNING A
LITTLE BELOW NORMAL THROUGH THE WEEK BEFORE RETUNING TO MORE
CLIMATOLOGICAL NORMS FOR THE WEEKEND...WITH OVERNIGHT LOWS GENERALLY
FOLLOWING A SIMILAR TREND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 750 AM EDT MON MAY 7 2012
PATCHY DENSE VALLEY FOG SHOULD BE LIFTING BY 14Z. WE COULD SEE A FEW
ISOLATED SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON. INCLUDED
VCTS IN THE TAFS. THIS EVENING THE STORMS WILL BECOME MORE
WIDESPREAD. THERE IS A THREAT FOR SOME OF THE STORMS TO BECOME
SEVERE. EXPECT MOSTLY VFR CONDITIONS...EXCEPT IN THE VICINITY OF THE
STORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...JJ
LONG TERM....MB
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
349 AM EDT MON MAY 7 2012
.SYNOPSIS...
LOW PRESSURE WILL MOVE ACROSS THE GREAT LAKES TUESDAY AND PUSH A
COLD FRONT SOUTH OF THE OHIO VALLEY LATER WEDNESDAY. THIS WILL
BRING SHOWERS AND A FEW THUNDERSTORMS LATER MONDAY THROUGH
WEDNESDAY WITH COOLER TEMPERATURES BY MID WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A MEANDERING FRONTAL BOUNDARY CURRENTLY EXTENDS FROM THE SOUTHERN
PLAINS INTO THE LOWER GREAT LAKES WITH SEVERAL LOWS TRACKING DOWN
IT. EACH OF THESE LOWS IS TENDING TO BE A FOCAL POINT FOR
CONVECTIVE ACTIVITY ALONG THE FRONT...WITH SEVERAL CONVECTIVE BLOW
UPS FROM TEXAS NORTHWARD TO ILLINOIS AND EASTWARD INTO MICHIGAN.
EAST OF THIS FRONTAL BOUNDARY...A RIDGE OF HIGH PRESSURE IS
LARGELY IN CONTROL...WHICH INCLUDES OVER THE PITTSBURGH REGION.
HOWEVER...THE UPPER RIDGE HAS BEEN LARGELY DAMPENED...WITH
GENERALLY NORTHWESTERLY UPPER LEVEL FLOW PRESENT OVER THE FORECAST
AREA AT THIS TIME. GIVEN THIS STEERING FLOW...AND CONVECTIVE
TRENDS OVER LOWER MICHIGAN AND NORTHWESTERN OHIO...IT WOULD
CERTAINLY SEEM THAT SOME AMOUNT OF RESIDUAL SHOWER ACTIVITY COULD
TRACK...PARTICULARLY INTO THE WESTERN ZONES AND NORTHERN ZONES OF
THE FORECAST AREA...BY LATE THIS MORNING AND AFTERNOON.
HOWEVER...THE ORGANIZATION OF THIS ACTIVITY IS LIKELY TO BE LESS
THAN OPTIMAL. ADDITIONALLY...CONVECTIVE BLOW OFF HAS ALREADY
COVERED MUCH OF THE AREA. THIS SHOULD HELP TO KEEP CAPE VALUES A
BIT LOWER THIS AFTERNOON THAN THEY MIGHT OTHERWISE BE GIVEN A
FAIRLY WELL MIXED BOUNDARY LAYER WITH ROUGHLY 25 KTS AT 850 MB AND
850 MB TEMPERATURES ON THE ORDER OF 2C HIGHER THAN YESTERDAY.
GIVEN ADDITIONALLY CLOUD COVER...TEMPERATURES AND HENCE CAPE
VALUES SHOULD BE HELD BACK A BIT...AND GIVEN MEDIOCRE 0-6 KM SHEAR
VALUES THIS AFTERNOON...WHILE A FEW MARGINALLY SEVERE STORMS MAY
BE POSSIBLE OVER OHIO...THE FORECAST WILL NOT BE FEATURING ANY
MENTION OF SUCH ACTIVITY. FRIES
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
THE MORE CRITICAL PORTION OF THE FORECAST STARTS TUESDAY NIGHT AS
THE NEXT LARGE SCALE SYSTEM TRACKS TOWARD THE AREA. PREVIOUS MODEL
RUNS HAVE ALL STRUGGLED WITH THE TIMING OF THIS SYSTEM GIVEN THE
FAIRLY WEAK REFLECTION OF IT AT 500 MB AS A SUBTLE RIPPLE IN THE
HEIGHT FIELD BETWEEN A DEEPER NORTHERN STREAM TROUGH AND THE
DEPARTING RIDGE FROM THE WEEKEND. TIMING IS NOW COMING INTO A BIT
BETTER VIEW FAVORING A VERY SLOW PROGRESSION OF ITS ASSOCIATED
FRONTAL BOUNDARY FROM MONDAY EVENING RIGHT THROUGH THE ENTIRE DAY
ON TUESDAY. THE MODEL CONSENSUS SEEMS TO LIKE THE IDEA OF THE VORT
CURRENTLY OVER MISSOURI EJECTING TO THE EAST CONCURRENT WITH THE
FRONTAL PASSAGE ACROSS THE AREA. GIVEN NEARLY FRONT PARALLEL 500
MB FLOW...THE RESULT WILL BE VERY SLOW EASTWARD MOVEMENT OF THE
FRONT AS THIS OCCURS. AS A RESULT...THE DEEP LAYER OF INSTABILITY
EXTENDING FROM THE SURFACE UP BEYOND 500 MB IS LIKELY TO BE EASILY
FOCUSED AND HARNESSED BY THE MID-LEVEL VORT THAT WILL BE MOVING
THROUGH THE REGION. IF WE COUPLE THIS WITH THE FRONTOGENETICAL
FORCING THE FLUX OF GULF MOISTURE INTO THE REGION...THE STAGE
SEEMS TO BE SET GIVEN THE SLOW MOTION OF THE FRONTAL BOUNDARY FROM
SOME FAIRLY COPIOUS RAINFALL. THE MODEL CONSENSUS FAVORS ROUGHLY
1-2 INCHES OF RAIN FROM MONDAY NIGHT THROUGH TUESDAY ACROSS MUCH
OF THE CWA...WHICH WHILE IMPRESSIVE...IS STILL NOT ENOUGH TO FAVOR
A FLASH FLOOD WATCH ISSUANCE. THIS IS MAINLY BECAUSE THOSE 2 INCH
AMOUNTS WOULD NEED TO FALL IN AN HOUR OR TWO BEFORE MUCH CONCERN
WOULD EXIST...AND AT THIS TIME...IT IS FAR TOO DIFFICULT TO
DETERMINE IF THAT IS POSSIBLE GIVEN FRONTAL TIMING PROBLEMS AS
WELL AS UNCERTAINTY AS TO THE DEGREE OF INSTABILITY. FOR
NOW...HEAVY RAIN WAS CARRIED IN THE FORECAST FOR TUESDAY NIGHT TO
ALERT AS TO THE LIKELIHOOD OF A PERIOD OF HEAVIER RAINFALL ALONG
THE FRONTAL BOUNDARY.
THE COLD FRONT FINALLY DOES KICK SOUTHEAST OF THE AREA BY
WEDNESDAY AS THE NORTHERN STREAM DIPS WELL SOUTH OF WHERE IT HAS
TAKEN RESIDENCE IN RECENT WEEKS. AS THIS OCCURS...UPPER TROUGHING
BECOMES CENTERED OVER THE CWA FROM WEDNESDAY THROUGH THURSDAY.
WITH COLDER AIR ALOFT ENTERING THE PICTURE...INSTABILITY WILL
AGAIN BECOME FAIRLY COMMON. HOWEVER...IT IS LIKELY TO BE MUCH MORE
SHALLOW. BUFKIT PROFILES SUGGEST 100-300 J/KG CAPES WITH POSITIVE
AREA UNABLE TO GET MUCH ABOVE THE -5C ISOTHERM. AS A
RESULT...CHARGE SEPARATION IS UNLIKELY TO BE EFFICIENT ENOUGH TO
SUPPORT THUNDERSTORM DEVELOPMENT...HOWEVER IT WOULD SEEM GIVEN LAKE
MOISTURE INFLUENCE AS WELL AS FAIRLY STEEP LOW LEVEL LAPSE
RATES...SCATTERED SHOWERS SHOULD DEVELOP BY WEDNESDAY AFTERNOON.
MORE IMPORTANTLY WITH THE DIPPING SOUTH OF THE POLAR JET WILL BE
THE CHANGE IN TEMPERATURES. RECENT 850 MB TEMPERATURES HAVE BEEN
IN THE +11 TO +14C RANGE. BY WEDNESDAY AND THURSDAY...MODEL 850 MB
TEMPERATURES SHOULD FALL INTO THE +2 TO +5C RANGE. THIS SEEMS
LIKELY TO TRANSLATE INTO 15-20 DEGREES OF SURFACE COOLING RELATIVE
TO RECENT DAYS. ADDITIONALLY...WITH NIGHTTIME STABILIZATION AND
RADIATIONAL COOLING...THERE IS SOME CHANCE OF A RETURN TO FROSTY
CONDITIONS BY THURSDAY NIGHT IN SOME AREAS. FRIES
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE WILL THEN MOVE INTO THE OHIO VALLEY KEEPING THE
WEATHER DRY THROUGH SATURDAY.
A COLD FRONT IS PROGGED TO BRING SCATTERED SHOWERS SUNDAY.
TEMPERATURES ARE FORECAST TO BE A FEW DEGREES BELOW NORMAL THURSDAY
AND FRIDAY...WARMING TO SLIGHTLY ABOVE NORMAL FOR THE WEEKEND.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
LOW CONFIDENCE FORECAST FOR TODAY. DECAYING COMPLEX TO THE NORTHWEST
CONTINUES TO PUSH CIRRUS CLOUDS OVER THE UPPER OHIO VALLEY. AN AREA
OF STRATUS HAS DEVELOPED OVER THE EASTERN APPALACHIANS AND HAS BEEN
TRYING TO DRIFT WESTWARD. HOWEVER, LL FLOW IS VERY WEAK AND USING
LATEST SAT PICS, RIDGES ARE HOLDING THE LOW CLOUDS AT BAY. FOR THE
FORECAST, WILL LEAVE OUT MENTION OF STRATUS AT ALL PORTS WITH THE
EXCEPTION OF DUJ. LATEST HRRR RUN IS SHOWING THE IFR STRATUS MAKING
IT TO DUJ SHORTLY AFTER ISSUANCE TIME AND REMAINING, THROUGH 12Z.
WILL GO WITH AN MVFR/IFR FORECAST AT DUJ, BUT WILL NEED TO MONITOR
CLOSELY OVERNIGHT.
MODELS ARE HAVING DIFFICULTY DECIDING WHAT TO DO WITH THE DECAYING
COMPLEX OVER THE WESTERN GREAT LAKES. CURRENT SAT AND RADAR PICS
SHOW THE ACTIVITY DISSIPATING QUICKLY. ADDITIONALLY, LATEST MODEL
RUNS ARE FORECASTING A STRENGTHENING OF THE MIDWEST RIDGE AS IT
MOVES EASTWARD THIS MORNING. HAVE VERY LITTLE CONFIDENCE IN HOW MUCH
ACTIVITY WILL DEVELOP TODAY. TRYING TO FOLLOW THE UL WAVES TO HELP
WITH TIMING AND PLACEMENT. THE WAVE ASSOCIATED WITH THE DYING
WESTERN COMPLEX MOVES ACROSS THE NORTH DURING THE POST-DAWN MORNING
HOURS. THE PROBLEM IS THAT IT IS RUNNING INTO THE UL RIDGE. WILL
INCLUDE A MENTION OF NON-RESTRICTIVE SHOWERS ACROSS THE NORTH THIS
MORNING. WITH THE LACK OF UL SUPPORT AND DEEP LAYERED MOISTURE, WILL
LEAVE OUT THE MENTION OF RAIN AT OTHER PORTS UNTIL LATE IN THE DAY,
AS THE FRONT APPROACHES.
.OUTLOOK...TONIGHT THROUGH THURSDAY...
RESTRICTIONS ARE EXPECTED TONIGHT AND THROUGH MUCH OF TUESDAY, AS A
COLD FRONT WILL SLOWLY MOVE THROUGH. LOW CONFIDENCE FORECAST FOR THE
REMAINDER OF THE OUTLOOK, AS A LARGE UL TROUGH WILL SETTLE INTO THE
UPPER OHIO VALLEY LATE WED AND THU.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS PITTSBURGH PA
107 AM EDT MON MAY 7 2012
.SYNOPSIS...
LOW PRESSURE WILL MOVE ACROSS THE GREAT LAKES TUESDAY AND PUSH A
COLD FRONT SOUTH OF THE OHIO VALLEY LATER WEDNESDAY. THIS WILL
BRING SHOWERS AND A FEW THUNDERSTORMS LATER MONDAY THROUGH
WEDNESDAY WITH COOLER TEMPERATURES BY MID WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
OVERNIGHT PERIOD STILL APPEARS TO BE DRY...WITH CLOUDS SLOWLY ON
THE INCREASE FROM BOTH THE WEST AND THE EAST. WITH DEWPOINTS
REMAINING IN THE LOW 60S ALONG THE RIDGES...EXPECT THAT LOW
STRATUS WILL DEVELOP BY DAYBREAK. RIGHT NOW THINKING THAT FOG
SHOULD NOT BE MUCH OF A CONCERN WITH STRATUS DEVELOPMENT.
FLOW WILL BECOME MORE SOUTHERLY BY MONDAY MORNING AS WARM FRONT
STRENGTHENS AND MOVES TOWARD I-80 WHILE LOW PRESSURE AND COLD
FRONT MOVE TO THE LOWER OHIO VALLEY. ISOLATED MORNING SHOWERS
POSSIBLE MONDAY BUT WIDESPREAD SHOWERS AND A FEW STORMS SHOULD
HOLD OFF UNTIL MID TO LATE AFTERNOON WITH DEEP MOISTURE AND LIFT
WITH APPROACHING SYSTEM. FAR WESTERN COUNTIES IN A SLIGHT RISK FOR
SEVERE LATE DAY MONDAY BUT THIS WILL DEPEND ON AMOUNT OF AVAILABLE
INSTABILITY. WILL MENTION IN HWO. MILD OVERNIGHT AND CONTINUED
ABOVE NORMAL MONDAY IN WARM ADVECTION.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
WIDESPREAD SHOWERS AND SOME THUNDERSTORMS MONDAY NIGHT INTO
TUESDAY AS SURFACE LOW MOVES INTO EASTERN GREAT LAKES WITH UPPER
LEVEL TROUGH DIGGING INTO THE OHIO VALLEY. COLD FRONT WILL BE
SLOWED A BUT TUESDAY AS UPPER TROUGH DIGS AND BRINGS UPPER FLOW
MORE PARALLEL TO FRONT FOR A TIME. AS SHORTWAVE AND SURFACE LOW
PUSHES TO NEW ENGLAND TUESDAY NIGHT FRONT WILL REACH SOUTH OF
MASON DIXON LINE WITH DECREASING RAIN CHANCES NORTHWEST TO
SOUTHEAST. MODELS IN DISAGREEMENT ON WHETHER ANOTHER WAVE WILL
FORM ON FRONT WEDNESDAY AND MOVE NORTHEAST TO PUSH HIGHER POPS
BACK NORTH AND WEST ACROSS REGION. DEEPENING TROUGH WITH HEIGHT
FALLS AT 500MB WILL ALLOW FOR INSTABILITY SHOWERS AT THE VERY
LEAST SO CHANCE POPS WEDNESDAY. TEMPERATURES WILL BEGIN A GRADUAL
COOL DOWN TUESDAY TRENDING BELOW NORMAL BY WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
SCATTERED SHOWERS ARE FORECAST TO TAPER OFF WEDNESDAY NIGHT AS A LOW
PRESSURE SYSTEM EXITS TO THE EAST. HIGH PRESSURE WILL THEN MOVE INTO
THE OHIO VALLEY THURSDAY...KEEPING THE WEATHER DRY THURSDAY
AFTERNOON THROUGH SATURDAY.
A COLD FRONT IS PROGGED TO BRING SCATTERED SHOWERS SUNDAY.
TEMPERATURES ARE FORECAST TO BE A FEW DEGREES BELOW NORMAL THURSDAY
AND FRIDAY...WARMING TO SLIGHTLY ABOVE NORMAL FOR THE WEEKEND.
&&
.AVIATION /05Z MONDAY THROUGH FRIDAY/...
LOW CONFIDENCE FORECAST FOR TODAY. DECAYING COMPLEX TO THE NORTHWEST
CONTINUES TO PUSH CIRRUS CLOUDS OVER THE UPPER OHIO VALLEY. AN AREA
OF STRATUS HAS DEVELOPED OVER THE EASTERN APPALACHIANS AND HAS BEEN
TRYING TO DRIFT WESTWARD. HOWEVER, LL FLOW IS VERY WEAK AND USING
LATEST SAT PICS, RIDGES ARE HOLDING THE LOW CLOUDS AT BAY. FOR THE
FORECAST, WILL LEAVE OUT MENTION OF STRATUS AT ALL PORTS WITH THE
EXCEPTION OF DUJ. LATEST HRRR RUN IS SHOWING THE IFR STRATUS MAKING
IT TO DUJ SHORTLY AFTER ISSUANCE TIME AND REMAINING, THROUGH 12Z.
WILL GO WITH AN MVFR/IFR FORECAST AT DUJ, BUT WILL NEED TO MONITOR
CLOSELY OVERNIGHT.
MODELS ARE HAVING DIFFICULTY DECIDING WHAT TO DO WITH THE DECAYING
COMPLEX OVER THE WESTERN GREAT LAKES. CURRENT SAT AND RADAR PICS
SHOW THE ACTIVITY DISSIPATING QUICKLY. ADDITIONALLY, LATEST MODEL
RUNS ARE FORECASTING A STRENGTHENING OF THE MIDWEST RIDGE AS IT
MOVES EASTWARD THIS MORNING. HAVE VERY LITTLE CONFIDENCE IN HOW MUCH
ACTIVITY WILL DEVELOP TODAY. TRYING TO FOLLOW THE UL WAVES TO HELP
WITH TIMING AND PLACEMENT. THE WAVE ASSOCIATED WITH THE DYING
WESTERN COMPLEX MOVES ACROSS THE NORTH DURING THE POST-DAWN MORNING
HOURS. THE PROBLEM IS THAT IT IS RUNNING INTO THE UL RIDGE. WILL
INCLUDE A MENTION OF NON-RESTRICTIVE SHOWERS ACROSS THE NORTH THIS
MORNING. WITH THE LACK OF UL SUPPORT AND DEEP LAYERED MOISTURE, WILL
LEAVE OUT THE MENTION OF RAIN AT OTHER PORTS UNTIL LATE IN THE DAY,
AS THE FRONT APPROACHES.
.OUTLOOK...TONIGHT THROUGH THURSDAY...
RESTRICTIONS ARE EXPECTED TONIGHT AND THROUGH MUCH OF TUESDAY, AS A
COLD FRONT WILL SLOWLY MOVE THROUGH. LOW CONFIDENCE FORECAST FOR THE
REMAINDER OF THE OUTLOOK, AS A LARGE UL TROUGH WILL SETTLE INTO THE
UPPER OHIO VALLEY LATE WED AND THU.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
843 PM EDT TUE MAY 8 2012
.SYNOPSIS...
ISSUED AT 429 PM EDT TUE MAY 8 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH AXIS
FROM JAMES BAY THROUGH WRN LAKE SUPERIOR TO ERN MN. AT THE SFC...A
TROUGH EXTENDED FROM SE LAKE SUPERIOR THROUGH CNTRL UPPER MI INTO
WRN WI. THE COMBINATION OF DIURNAL HEATING...STEEP MID LEVEL LAPSE
RATES AND WEAK TO MODERATE QVECTOR CONV ASSOCIATED WITH THE MID
LEVEL TROUGH HAS SUPPORTED SCT/NMRS SHRA OVER MOST OF INLAND UPPER
MI. IN ADDITION...SOME ISOLD TSRA WITH SMALL HAIL HAVE ALSO
DEVELOPED. THE GREATEST SHRA COVERAGE AND HEAVIEST RAIN WAS OVER THE SE
CWA WHERE LOW LEVEL CONV WITH THE TROUGH AND LAKE BREEZE WAS MOST
PROMINENT.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 429 PM EDT TUE MAY 8 2012
AS THE MID LEVEL AND SFC TROUGH SHIFTS TO THE SOUTHEAST AND DIURNAL
HEATING SUBSIDES...EXPECT THE AREA OF SHOWERS TO DIMINISH AND SAG TO
THE SOUTH. SHOWERS MAY STILL BE NMRS/WIDESPREAD LATE THIS AFTERNOON
20Z-24Z BUT BY 00Z-03Z...THE REMAINING PCPN SHOULD BECOME SCT/ISOLD
AND END BY AROUND MIDNIGHT. HOWEVER...WITH ABUNDANT LOW LEVEL
MOISTURE REMAINING INCREASING CYCLONIC NE TO N FLOW (9505-850 MB N
WINDS OF 20-30 KT) INTO N CNTRL UPPER MI...HIGHER RES MODELS SUGGEST
LIGHT PCPN WILL DEVELOP IN LINE WITH PREVIOUS FCST.
MODELS SUGGEST THAT THE SHARP BACK EDGE OF THE LOW LEVEL
MOISTURE...PER VIS IMAGERY...WILL MOVE N-S THROUGH THE AREA BTWN
09Z-15Z. SO...ANY PCPN SHOULD END BY EARLY WED WITH PARTLY TO MOSTLY
SUNNY SKIES BY MIDDAY. SUNSHINE/MIXING SHOULD ALLOW INLAND TEMPS TO
CLIMB TO NEAR 60 BUT ONSHORE FLOW NORTH WILL KEEP READINGS IN THE
UPPER 40S TO LOWER 50S NEAR LAKE SUPERIOR.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 429 PM EDT TUE MAY 8 2012
A RIDGE OF HIGH PRESSURE...CENTERED FROM WY TO N MANITOBA WILL BE
PUSHING ACROSS THE UPPER GREAT LAKES WEDNESDAY NIGHT THROUGH FRIDAY
MORNING. WE CONTINUE TO LOOK INTO WEDNESDAY NIGHT/THURSDAY MORNING
AS BEING THE COLDEST TIME PERIOD...WITH LIGHT WINDS AND RELATIVELY
LOW PW VALUES. INCLUDED THE MENTION OF FREEZING TEMPS FOR THE
INTERIOR WEST IN THE HWO.
THE MAIN FEATURE OF INTEREST PRECIPITATION WISE WILL BE THE STACKED
LOW OVER N CENTRAL CANADA FOR THE LATTER HALF OF THE WORK WEEK. THE
LOW ITSELF WILL SLOWLY SHIFT ACROSS HUDSON BAY BY SATURDAY
NIGHT...WHERE IT WILL LIKELY LINGER THROUGH THE REMAINDER OF THE
PERIOD. WAVES ROTATING AROUND THE LOW SHOULD BRING THE INITIAL SFC
TROUGH/COLD FRONT TO FAR W LAKE SUPERIOR AT 18Z FRIDAY...CENTRAL
UPPER MI BY 00Z SATURDAY...AND EAST OF ALL UPPER MI BY 12Z SATURDAY.
TIMING DIFFERS BY 3-5HRS BETWEEN THE VARIOUS MODELS...WITH THE
08/00Z CANADIAN ON THE SLOW END...AND THE 08/00Z ECMWF AND 08/12Z
BEING ON THE QUICKER SOLUTIONS. THE 08/06Z GFS RUNS THE MIDDLE
GROUND BETWEEN THESE VARYING SOLUTIONS. ADDED THE MENTION OF
ISOLATED TS OVER THE WITH SB/MU CAPE VALUES OF 300 TO 600J/KG.
GIVEN THE STRENGTHENING SOUTHERLY WINDS AHEAD OF THE COLD FRONT
FRIDAY AFTERNOON WITH THE PEAK OF DAYTIME HEATING...FIRE WX CONCERNS
MAY INCREASE...PARTICULARLY OVER THE E HALF WHERE MORE LIMITED
HUMIDITY VALUES WILL LIKELY EXIST. WILL ALSO CONTINUE TO HIGHLIGHT
DOWNSLOPE AREAS FOR SOME OF THE WARMER TEMPS ACROSS THE CWA. SOME
GUIDANCE IS HINTING AT THE POTENTIAL OF 80 DEGREES OVER THE BARAGA
PLAINS FRIDAY.
EXPECT SHOWERS TO COME TO AN END SATURDAY MORNING...WITH DRY WEATHER
THEN TAKING HOLD THROUGH TUESDAY. GIVEN W TO NW FLOW ALOFT...THERE
COULD BE A SMALLER CHANCE OF SHOWERS...BUT WILL NOT INCLUDE AT THIS
TIME GIVEN THE LOW PROBABILITY...WITH HIGH PRESSURE SLIDING IN FROM
THE N/CENTRAL PLAINS. MODELS ARE NOT DOING THE BEST AT COMING
TOGETHER ON A SOLUTION FOR MONDAY...WITH THE POTENTIAL OF ANOTHER
COLD FRONT MOVING NW TO SE OVER THE CWA /LIKE THE 08/12Z ECMWF/.
THIS MAY BE ONE AREA OF THE FCST THAT CHANGES MORE THAN ANY OTHER
OVER THE NEXT SEVERAL DAYS. OTHERWISE...HIGHS IN THE 60S INLAND FROM
THE GREAT LAKES LOOK TO BE THE RULE FROM SUNDAY THROUGH NEXT TUESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 839 PM EDT TUE MAY 8 2012
AN UPPER LEVEL DISTURBANCE MOVING ACROSS THE AREA IS STILL
SUPPORTING SHOWERS THIS EVENING BUT THESE SHOWERS WILL REMAIN SOUTH
AND EAST OF THE TAF SITES. LINGERING LOW-LVL MOISTURE WILL RESULT IN
MVFR CIGS OVERNIGHT INTO EARLY WED FOR KIWD AND KCMX. NORTH WINDS AND
FAVORABLE UPSLOPE FLOW AT KSAW SHOULD RESULT IN ALT LANDING MINS
BEING REACHED BY LATE EVENING AND OVERNIGHT IN STRATUS AND POSSIBLE
FOG.
DRIER AIR MOVING IN FROM THE NORTH WILL LEAD TO QUICKLY IMPROVING
CONDITIONS TO VFR BY MID WED MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 429 PM EDT TUE MAY 8 2012
ABUNDANT LOW-LEVEL MOISTURE AND LIGHT CONVERGENT WIND FLOW HAS LEAD
TO AREAS OF FOG (DENSE AT TIMES) ACROSS LAKE SUPERIOR. THUS DENSE
FOG ADVY CONTINUES FOR MUCH OF THE LAKE. FOG WILL LIFT TONIGHT AS
DRIER AIR ARRIVES FROM THE N.
LACK OF SIGNIFICANT WEATHER FEATURES WILL RESULT IN WINDS MOSTLY
UNDER 20KT ACROSS LAKE SUPERIOR THRU THE END OF THE WEEK. THE
STRONGER WINDS THIS WEEK WILL OCCUR THIS EVENING INTO WED OVER
ERN LAKE SUPERIOR AS A LOW PRES TROF EXITS THE AREA...AND ALSO FRI
AS ANOTHER LOW PRES TROF MOVES ACROSS THE UPPER GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LSZ249>251-
266-267.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...KF
AVIATION...VOSS
MARINE...JLB
AREA FORECAST DISCUSSION
NWS DULUTH MN
720 PM CDT TUE MAY 8 2012
.UPDATE...
REFRESHED EVENING FORECAST BASED ON QUICKLY DIMINISHING RADAR
TRENDS AND ADJUSTED SKY COVER TO REFLECT ADVANCING CLEARING FROM
CANADA. INTRODUCED PATCHY FOG TO ALL ZONES IN ANTICIPATION OF
CLEARING SKIES AND LIGHT WINDS OVERNIGHT RESULTING RADIATIONAL
COOLING/FOG. LATEST NAM BUFR SOUNDINGS SUGGEST BEST CHC FOR FOG
WILL BE ALONG AND SOUTH OF US HIGHWAY 2. NORTH OF THIS
LINE...MUCH DRIER CANADIAN AIR WILL ARRIVE DURING THE EARLY
MORNING HRS.
&&
.PREV DISCUSSION... /ISSUED 638 PM CDT TUE MAY 8 2012/
AVIATION.../00Z TAF ISSUANCE/
DIURNALLY DRIVEN SHOWERS BEGINNING TO DIMINISH FROM NORTH TO
SOUTH. CLOUDS SCATTER NORTH OF THE INTERNATIONAL BORDER AND WILL
MOVE INTO THE TERMINALS LATER TONIGHT. SOME FOG PATCHES MAY OCCUR
AFTER 06Z AS THE SKIES PARTIALLY CLEAR. SKIES WILL ME MOSTLY CLEAR
FOR WEDNESDAY WITH NORTHWEST WINDS AROUND 10 KNOTS.
PREV DISCUSSION... /ISSUED 342 PM CDT TUE MAY 8 2012/
SFC/MID LVL LOW COLLAPSING SOUTHWARD THIS AFTERNOON AS PROGRESSIVE
FLOW ALOFT CONTINUES. ELONGATED SFC TROUGH/CONVERGENCE ZONE HAS BEEN
A RESERVOIR OF LOW LVL INSTABILITY TODAY AS DEPICTED BY RUC13 THETAE
FIELDS IN LOWEST 3/4K FT. UPPER COLD POOL HAS PROVIDED OPPORTUNITY
FOR STEEP LAPSE RATES AND AREAS OF CONVECTION HAVE DEVELOPED. MOST
PERSISTENT PRECIP HAS BEEN LOCATED ALONG/NORTH OF DEEP SHEAR AXIS
ACROSS IRON RANGE...SLOWLY MOVING SOUTH. A FEW REPORTS OF SMALL HAIL
WERE RECEIVED ACROSS WISCONSIN ZONES EARLY THIS AFTERNOON.
TONIGHT...OTHER THAN EARLY EVENING CONVECTION POTENTIAL...CONDITIONS
SHOULD TREND TOWARDS LESS PRECIP AND DECREASING CLOUD COVER FROM
NORTH TO SOUTH. CONFIDENCE NOT HIGH ON BR/FG DEVELOPMENT SO HAVE
LEFT OUT OF GRIDS/ZFP FOR NOW. LOWEST TEMPS SHOULD OCCUR IN
ARROWHEAD WHERE CLEARING OCCURS FIRST.
TOMORROW/TOMORROW NIGHT...SFC/MID LVL RIDGING WILL DOMINATE
WEDNESDAY. EXPECT DECENT WARMING WITH MAX TEMPS NEAR/ABOVE CLIMO.
EXPECT AN AREA OF INCREASING HIGH CLOUDS TO PUSH ACROSS RIDGE AXIS INTO CWA
DURING THE AFTN/EVENING HOURS. TIMING IS A BIT OF A CHALLENGE AS
MDLS DIFFER ON EXTENT/SPEED OF HIGH LVL COND PRESS DEFICITS.
LONG TERM...THURSDAY THROUGH TUESDAY.
MAIN FORECAST CONCERN FOR THE EXTENDED FORECAST PERIOD IS A STRONG
COLD FRONT THAT IS PROGGED TO TRACK ACROSS THE UPPER MIDWEST
FRIDAY/FRIDAY NIGHT. AHEAD OF THE FRONT...A WARM-UP IS EXPECTED FOR
THURSDAY WITH HIGHS IN THE 70S. THE FRONT WILL TAP THIS WARMTH ALONG
WITH INCREASING MOISTURE TO PRODUCE A CHANCE OF SHOWERS AND STORMS
ACROSS THE NORTHLAND FRIDAY AND FRIDAY NIGHT. THE PRECIPITATION WILL
END BY SATURDAY...WITH MAINLY DRY CONDITIONS EXPECTED THROUGH EARLY
NEXT WEEK.
&&
.POINT TEMPS/POPS...
DLH 38 62 42 69 / 10 0 0 0
INL 34 65 41 73 / 10 0 10 0
BRD 38 65 43 75 / 40 0 10 0
HYR 36 64 38 72 / 30 0 0 0
ASX 36 63 39 71 / 10 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...GRANING
AREA FORECAST DISCUSSION
NWS DULUTH MN
638 PM CDT TUE MAY 8 2012
.AVIATION.../0Z TAF ISSUANCE/
DIURNALLY DRIVEN SHOWERS BEGINNING TO DIMINISH FROM NORTH TO
SOUTH. CLOUDS SCATTER NORTH OF THE INTERNATIONAL BORDER AND WILL
MOVE INTO THE TERMINALS LATER TONIGHT. SOME FOG PATCHES MAY OCCUR
AFTER 06Z AS THE SKIES PARTIALLY CLEAR. SKIES WILL ME MOSTLY CLEAR
FOR WEDNESDAY WITH NORTHWEST WINDS AROUND 10 KNOTS.
&&
.PREV DISCUSSION... /ISSUED 342 PM CDT TUE MAY 8 2012/
SFC/MID LVL LOW COLLAPSING SOUTHWARD THIS AFTERNOON AS PROGRESSIVE
FLOW ALOFT CONTINUES. ELONGATED SFC TROUGH/CONVERGENCE ZONE HAS BEEN
A RESERVOIR OF LOW LVL INSTABILITY TODAY AS DEPICTED BY RUC13 THETAE
FIELDS IN LOWEST 3/4K FT. UPPER COLD POOL HAS PROVIDED OPPORTUNITY
FOR STEEP LAPSE RATES AND AREAS OF CONVECTION HAVE DEVELOPED. MOST
PERSISTENT PRECIP HAS BEEN LOCATED ALONG/NORTH OF DEEP SHEAR AXIS
ACROSS IRON RANGE...SLOWLY MOVING SOUTH. A FEW REPORTS OF SMALL HAIL
WERE RECEIVED ACROSS WISCONSIN ZONES EARLY THIS AFTERNOON.
TONIGHT...OTHER THAN EARLY EVENING CONVECTION POTENTIAL...CONDITIONS
SHOULD TREND TOWARDS LESS PRECIP AND DECREASING CLOUD COVER FROM
NORTH TO SOUTH. CONFIDENCE NOT HIGH ON BR/FG DEVELOPMENT SO HAVE
LEFT OUT OF GRIDS/ZFP FOR NOW. LOWEST TEMPS SHOULD OCCUR IN
ARROWHEAD WHERE CLEARING OCCURS FIRST.
TOMORROW/TOMORROW NIGHT...SFC/MID LVL RIDGING WILL DOMINATE
WEDNESDAY. EXPECT DECENT WARMING WITH MAX TEMPS NEAR/ABOVE CLIMO.
EXPECT AN AREA OF INCREASING HIGH CLOUDS TO PUSH ACROSS RIDGE AXIS INTO CWA
DURING THE AFTN/EVENING HOURS. TIMING IS A BIT OF A CHALLENGE AS
MDLS DIFFER ON EXTENT/SPEED OF HIGH LVL COND PRESS DEFICITS.
LONG TERM...THURSDAY THROUGH TUESDAY.
MAIN FORECAST CONCERN FOR THE EXTENDED FORECAST PERIOD IS A STRONG
COLD FRONT THAT IS PROGGED TO TRACK ACROSS THE UPPER MIDWEST
FRIDAY/FRIDAY NIGHT. AHEAD OF THE FRONT...A WARM-UP IS EXPECTED FOR
THURSDAY WITH HIGHS IN THE 70S. THE FRONT WILL TAP THIS WARMTH ALONG
WITH INCREASING MOISTURE TO PRODUCE A CHANCE OF SHOWERS AND STORMS
ACROSS THE NORTHLAND FRIDAY AND FRIDAY NIGHT. THE PRECIPITATION WILL
END BY SATURDAY...WITH MAINLY DRY CONDITIONS EXPECTED THROUGH EARLY
NEXT WEEK.
&&
.POINT TEMPS/POPS...
DLH 38 62 42 69 / 10 0 0 0
INL 34 65 41 73 / 10 0 10 0
BRD 38 65 43 75 / 40 0 10 0
HYR 36 64 38 72 / 40 0 0 0
ASX 36 63 39 71 / 10 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
AVIATION...KK
AREA FORECAST DISCUSSION
NWS DULUTH MN
1258 PM CDT MON MAY 7 2012
.AVIATION.../18Z TAF ISSUANCE/
A COMPLEX CLOUD FORECAST IS SHAPING UP OVER THE DURATION OF THE
TAF CYCLE. A DOUBLE LOW PRESSURE SYSTEM WILL GRADUALLY MORPH INTO
ONE MAIN LOW PRESSURE SYSTEM OVER THE NORTHERN GREAT LAKES THROUGH
THE TAF CYCLE. THE RESULT WILL BE A WEST TO EAST LOW PRESSURE
TROUGH THAT WILL HELP TO FOCUS SHOWERS AND LOWERING CLOUD HEIGHTS.
TODAY IT LOOKS LIKE ANY POSSIBLE MVFR CIGS/VSBYS WOULD BE CONFINED
TO THE KINL AREA. HOWEVER...MVFR AND SOME IFR CONDITIONS SHOULD
BECOME THE NORM ACROSS THE AREA TONIGHT AND INTO TUESDAY MORNING.
&&
.PREV DISCUSSION... /ISSUED 1039 AM CDT MON MAY 7 2012/
UPDATE...ZFP/GRIDS IN VERY GOOD CONDITION SO ONLY MINOR TWEAKS
MADE AT THIS POINT. GUSTY WINDS SHOULD DEVELOP TODAY WITHIN
RELATIVE NARROW DRY SLOT AS MIXING LAYER DEEPENS AND MOMENTUM
TRANSFER INCREASES. PROGRESSIVE NATURE OF MID LVL THERMAL POOL
MAKES INSTABILITY CLOUD DEVELOPMENT FAIRLY RAPID. INSTABILITY
PARAMETERS ARE NOT VERY IMPRESSIVE WITH LATEST SREF SHOWING
HIGHEST PROBABILITY NEAR BORDERLAND/IRON RANGE THIS AFTN. WILL
LEAVE ISO TRW IN MOST OF PRECIP AREA TODAY AS FCST 85/50H LAPSE
RATES INCREASE TO GREATER THAN 6C/KM.
PREV DISCUSSION... /ISSUED 636 AM CDT MON MAY 7 2012/
UPDATE...
UPDATED THE FORECAST TO REFLECT THE LATEST CLOUD AND FOG TRENDS.
IT APPEARS THICKER FOG HAS FORMED ALONG THE NORTH SHORE...SO
ALTERED THE MORNING FORECAST FROM PATCHY FOG TO AREAS OF FOG FOR
THAT AREA. ALSO...THE LATEST HRRR AND NAM RUNS SUGGEST MORE
EXTENSIVE CLOUD COVER MOVING IN FROM THE WEST TODAY...SO INCREASED
CLOUD COVER INTO THIS AFTERNOON.
PREV DISCUSSION... /ISSUED 627 AM CDT MON MAY 7 2012/
AVIATION...12Z TAFS.
DRY SLOT WORKING ITS WAY ACROSS THE AREA EARLY IN THE TAF CYCLE
WILL PRESENT A BRIEF WINDOW OF VFR. LIFR/IFR CIGS/VSBYS WITH
PATCHY BR/FOG AHEAD OF THE DRY SLOT WILL EXIT THE AREA FAIRLY
QUICKLY. BEHIND THE DRY SLOT...MVFR CIGS WILL SPREAD ACROSS THE
TAF SITES WITH SOME GUSTY SFC WINDS FROM 16Z TO 22Z. SOME SHOWERS
MAY OCCUR AFTER 21Z AS SFC LOW AND UPPER LOW DROP THROUGH THE
AREA. UPSTREAM SFC OBS INDICATE THE SHOWERS WILL BE ISOLD AND HAVE
VCSH TO ACCOUNT FOR THIS ISOLD NATURE.
PREV DISCUSSION... /ISSUED 337 AM CDT MON MAY 7 2012/
SHORT TERM...[NOW - TUESDAY]
AT 0830Z...THERE WAS A SURFACE LOW AND AN ASSOCIATED MID/UPPER
LEVEL LOW CENTERED OVER SOUTHERN SASKATCHEWAN. AN ASSOCIATED
OCCLUDED FRONT STRETCHED SOUTHEAST THROUGH THE WESTERN FA. MUCH OF
THE FA WAS COVERED WITH VERY LOW OVERCAST STRATUS...AND IN
ADDITION BKN/OVC HIGH CLOUDS COVERED THE SOUTHEASTERN FA. THERE
WAS SOME FOG ACROSS THE NORTHLAND...WITH SOME RECENT REPORTS NEAR
THE BRAINERD LAKES AND TWIN PORTS AREAS. THE WINDS WERE MOSTLY
CALM OR VERY LIGHT AND VARIABLE...EXCEPT FOR DEVELOPING LIGHT
SOUTHERLY WINDS ACROSS THE NORTHERN AND WESTERN FA. TEMPERATURES
WERE IN THE 40S TO LOW 50S. THE RADAR INDICATED LINGERING SHOWERS
ACROSS THE EASTERN FA...NAMELY THE ARROWHEAD.
EARLY THIS MORNING...THE OCCLUDED FRONT WILL CONTINUE TO MOVE
EASTWARD THROUGH THE FA...AND THE SHOWERS IN THE EASTERN FA WILL
GRADUALLY MOVE OUT OF THE FA. THE VERY LOW STRATUS AND PATCHY FOG
MAY LINGER THROUGH AT LEAST DAWN.
TODAY...THE SURFACE AND MID/UPPER LEVEL LOWS IN SOUTHERN
SASKATCHEWAN WILL MOVE INTO NORTHERN MINNESOTA. MIXING WILL
INCREASE THIS MORNING WITH THE INCREASING WESTERLY WINDS. THIS
SHOULD BEGIN TO BURN OFF THE EARLY MORNING STRATUS AND PATCHY
FOG...AS WELL AS GIVE THE FA SOME MORNING SUNSHINE. PATCHY FOG MAY
LINGER THROUGH PART OF THE MORNING ACROSS THE EASTERN FA WHERE THE
WINDS WILL BE LIGHTEST. THE COLD AIR ALOFT AND THE RELATIVELY LOW
CONVECTIVE TEMPERATURES TODAY SHOULD RESULT IN PLENTY OF CUMULUS
CLOUDS DEVELOPING BY THIS AFTERNOON. THE MODELS ARE IN GOOD
AGREEMENT THAT THE NORTHERN AND WESTERN FA COULD GET RAIN
SHOWERS. MODEL SUPPORT FOR INSTABILITY IS LIMITED...ABOUT 300 J/KG
OR LESS...BUT ENOUGH TO WARRANT INCLUDING A MENTION OF ISOLATED
THUNDER WITH THE SHOWERS. THE MORNING SUNSHINE SHOULD ALLOW
TEMPERATURES TO CLIMB TO THE LOWER 60S ACROSS MOST OF THE FA.
TONIGHT...THE SURFACE AND MID/UPPER TROUGH WILL MOVE
SOUTHEASTWARDS THROUGH THE FA. EXPECT A CLOUDY AND COOL NIGHT WITH
CONTINUING CHANCES OF RAIN SHOWERS...MAINLY ACROSS THE NORTHERN
HALF OF THE FA.
TUESDAY...THE NEGATIVELY TILTED MID/UPPER LEVEL TROUGH WILL SWING
THROUGH THE GREAT LAKES REGION THROUGH THE DAY ON TUESDAY AND THE
ASSOCIATED STACKED SURFACE LOW WILL SLIDE SOUTH TO SOUTHEASTERN
MINNESOTA BY TUESDAY EVENING. FORECAST SOUNDINGS ARE QUITE
SATURATED THROUGH THE MID LEVELS THROUGH THE DAY AND INTO THE
EVENING. AS THAT LOW PRESSURE CENTER SWINGS SOUTH...THE FA WILL
REMAIN CLOUDY AND WET...BUT COOLER THAN PREVIOUS DAY. THE
SOUNDINGS TUESDAY AFTERNOON ALSO SHOW SOME WEAK CAPE VALUES ACROSS
THE AREA AS THE AFTERNOON HEATING PICKS UP. HAVE INCLUDED ISOLATED
THUNDER TO ADDRESS THIS.
LONG TERM...[TUESDAY NIGHT - SUNDAY]
A LONG WAVE TROF WILL CLEAR THE FA TUESDAY EVENING WHILE ONE MORE
PIECE OF ENERGY DROPS QUICKLY INTO THE AREA BEHIND IT. THESE
FEATURES WARRANT THE POPS CURRENTLY IN PLACE OVER THE EASTERN TWO
THIRDS OF THE AREA TUESDAY EVENING. AFTER 06Z WEDNESDAY, UPPER
LEVEL AND SFC RIDGING BUILD INTO THE FA WITH A CLEARING SKY. THE
SFC RIDGING MOVES TO THE SOUTHERN GREAT LAKES WHILE UPPER RIDGING
REMAINS OVER THE FA THROUGH THURSDAY. A SW RETURN FLOW SETS UP IN
THURSDAY AFTERNOON ALLOWING WARM, MOIST AIR TO ADVECT INTO THE
AREA. THURSDAY NIGHT FINDS A STRONG COLD FRONT MOVING TOWARDS THE
FA WITH THUNDERSTORMS IN THE VICINITY OF THE FRONT. THE GFS, GEM,
NOGAPS AND DGEX ARE THE FASTEST WITH THE FRONT WHILE THE 00Z ECMWF
IS SLOWEST. TRIED TO LEAN MORE TOWARD THE ECMWF AS ALL MODELS ARE
TOO QUICK TO BREAK DOWN RIDGING DOWNSTREAM. THIS TREND CONTINUES
ON FRIDAY AND KEPT THE SAME APPROACH. LEFT SOME POPS OVER THE
EASTERN THIRD OF THE FA FRIDAY NIGHT AS PCPN MAY LINGER BEHIND THE
DEPARTING FRONT WITH THE CAA. A QUASI-ZONAL FLOW SETS UP SATURDAY
AND SUNDAY. A WEAK SHORT WAVE CLIPS THE EASTERN PORTION OF THE FA
SUNDAY AND HAVE SMALL POPS TO ACCOUNT FOR ITS PASSAGE.
&&
.POINT TEMPS/POPS...
DLH 63 42 52 39 / 10 20 60 20
INL 59 41 55 35 / 50 50 50 10
BRD 63 43 55 40 / 20 20 60 10
HYR 68 42 54 38 / 10 10 60 30
ASX 64 42 50 38 / 10 20 60 30
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...CANNON
LONG TERM....DAP
AVIATION...DAP
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1039 AM CDT MON MAY 7 2012
.UPDATE...ZFP/GRIDS IN VERY GOOD CONDITION SO ONLY MINOR TWEAKS
MADE AT THIS POINT. GUSTY WINDS SHOULD DEVELOP TODAY WITHIN
RELATIVE NARROW DRY SLOT AS MIXING LAYER DEEPENS AND MOMENTUM
TRANSFER INCREASES. PROGRESSIVE NATURE OF MID LVL THERMAL POOL
MAKES INSTABILITY CLOUD DEVELOPMENT FAIRLY RAPID. INSTABILITY
PARAMETERS ARE NOT VERY IMPRESSIVE WITH LATEST SREF SHOWING
HIGHEST PROBABILITY NEAR BORDERLAND/IRON RANGE THIS AFTN. WILL
LEAVE ISO TRW IN MOST OF PRECIP AREA TODAY AS FCST 85/50H LAPSE
RATES INCREASE TO GREATER THAN 6C/KM.
&&
.PREV DISCUSSION... /ISSUED 636 AM CDT MON MAY 7 2012/
UPDATE...
UPDATED THE FORECAST TO REFLECT THE LATEST CLOUD AND FOG TRENDS.
IT APPEARS THICKER FOG HAS FORMED ALONG THE NORTH SHORE...SO
ALTERED THE MORNING FORECAST FROM PATCHY FOG TO AREAS OF FOG FOR
THAT AREA. ALSO...THE LATEST HRRR AND NAM RUNS SUGGEST MORE
EXTENSIVE CLOUD COVER MOVING IN FROM THE WEST TODAY...SO INCREASED
CLOUD COVER INTO THIS AFTERNOON.
PREV DISCUSSION... /ISSUED 627 AM CDT MON MAY 7 2012/
AVIATION...12Z TAFS.
DRY SLOT WORKING ITS WAY ACROSS THE AREA EARLY IN THE TAF CYCLE
WILL PRESENT A BRIEF WINDOW OF VFR. LIFR/IFR CIGS/VSBYS WITH
PATCHY BR/FOG AHEAD OF THE DRY SLOT WILL EXIT THE AREA FAIRLY
QUICKLY. BEHIND THE DRY SLOT...MVFR CIGS WILL SPREAD ACROSS THE
TAF SITES WITH SOME GUSTY SFC WINDS FROM 16Z TO 22Z. SOME SHOWERS
MAY OCCUR AFTER 21Z AS SFC LOW AND UPPER LOW DROP THROUGH THE
AREA. UPSTREAM SFC OBS INDICATE THE SHOWERS WILL BE ISOLD AND HAVE
VCSH TO ACCOUNT FOR THIS ISOLD NATURE.
PREV DISCUSSION... /ISSUED 337 AM CDT MON MAY 7 2012/
SHORT TERM...[NOW - TUESDAY]
AT 0830Z...THERE WAS A SURFACE LOW AND AN ASSOCIATED MID/UPPER
LEVEL LOW CENTERED OVER SOUTHERN SASKATCHEWAN. AN ASSOCIATED
OCCLUDED FRONT STRETCHED SOUTHEAST THROUGH THE WESTERN FA. MUCH OF
THE FA WAS COVERED WITH VERY LOW OVERCAST STRATUS...AND IN
ADDITION BKN/OVC HIGH CLOUDS COVERED THE SOUTHEASTERN FA. THERE
WAS SOME FOG ACROSS THE NORTHLAND...WITH SOME RECENT REPORTS NEAR
THE BRAINERD LAKES AND TWIN PORTS AREAS. THE WINDS WERE MOSTLY
CALM OR VERY LIGHT AND VARIABLE...EXCEPT FOR DEVELOPING LIGHT
SOUTHERLY WINDS ACROSS THE NORTHERN AND WESTERN FA. TEMPERATURES
WERE IN THE 40S TO LOW 50S. THE RADAR INDICATED LINGERING SHOWERS
ACROSS THE EASTERN FA...NAMELY THE ARROWHEAD.
EARLY THIS MORNING...THE OCCLUDED FRONT WILL CONTINUE TO MOVE
EASTWARD THROUGH THE FA...AND THE SHOWERS IN THE EASTERN FA WILL
GRADUALLY MOVE OUT OF THE FA. THE VERY LOW STRATUS AND PATCHY FOG
MAY LINGER THROUGH AT LEAST DAWN.
TODAY...THE SURFACE AND MID/UPPER LEVEL LOWS IN SOUTHERN
SASKATCHEWAN WILL MOVE INTO NORTHERN MINNESOTA. MIXING WILL
INCREASE THIS MORNING WITH THE INCREASING WESTERLY WINDS. THIS
SHOULD BEGIN TO BURN OFF THE EARLY MORNING STRATUS AND PATCHY
FOG...AS WELL AS GIVE THE FA SOME MORNING SUNSHINE. PATCHY FOG MAY
LINGER THROUGH PART OF THE MORNING ACROSS THE EASTERN FA WHERE THE
WINDS WILL BE LIGHTEST. THE COLD AIR ALOFT AND THE RELATIVELY LOW
CONVECTIVE TEMPERATURES TODAY SHOULD RESULT IN PLENTY OF CUMULUS
CLOUDS DEVELOPING BY THIS AFTERNOON. THE MODELS ARE IN GOOD
AGREEMENT THAT THE NORTHERN AND WESTERN FA COULD GET RAIN
SHOWERS. MODEL SUPPORT FOR INSTABILITY IS LIMITED...ABOUT 300 J/KG
OR LESS...BUT ENOUGH TO WARRANT INCLUDING A MENTION OF ISOLATED
THUNDER WITH THE SHOWERS. THE MORNING SUNSHINE SHOULD ALLOW
TEMPERATURES TO CLIMB TO THE LOWER 60S ACROSS MOST OF THE FA.
TONIGHT...THE SURFACE AND MID/UPPER TROUGH WILL MOVE
SOUTHEASTWARDS THROUGH THE FA. EXPECT A CLOUDY AND COOL NIGHT WITH
CONTINUING CHANCES OF RAIN SHOWERS...MAINLY ACROSS THE NORTHERN
HALF OF THE FA.
TUESDAY...THE NEGATIVELY TILTED MID/UPPER LEVEL TROUGH WILL SWING
THROUGH THE GREAT LAKES REGION THROUGH THE DAY ON TUESDAY AND THE
ASSOCIATED STACKED SURFACE LOW WILL SLIDE SOUTH TO SOUTHEASTERN
MINNESOTA BY TUESDAY EVENING. FORECAST SOUNDINGS ARE QUITE
SATURATED THROUGH THE MID LEVELS THROUGH THE DAY AND INTO THE
EVENING. AS THAT LOW PRESSURE CENTER SWINGS SOUTH...THE FA WILL
REMAIN CLOUDY AND WET...BUT COOLER THAN PREVIOUS DAY. THE
SOUNDINGS TUESDAY AFTERNOON ALSO SHOW SOME WEAK CAPE VALUES ACROSS
THE AREA AS THE AFTERNOON HEATING PICKS UP. HAVE INCLUDED ISOLATED
THUNDER TO ADDRESS THIS.
LONG TERM...[TUESDAY NIGHT - SUNDAY]
A LONG WAVE TROF WILL CLEAR THE FA TUESDAY EVENING WHILE ONE MORE
PIECE OF ENERGY DROPS QUICKLY INTO THE AREA BEHIND IT. THESE
FEATURES WARRANT THE POPS CURRENTLY IN PLACE OVER THE EASTERN TWO
THIRDS OF THE AREA TUESDAY EVENING. AFTER 06Z WEDNESDAY, UPPER
LEVEL AND SFC RIDGING BUILD INTO THE FA WITH A CLEARING SKY. THE
SFC RIDGING MOVES TO THE SOUTHERN GREAT LAKES WHILE UPPER RIDGING
REMAINS OVER THE FA THROUGH THURSDAY. A SW RETURN FLOW SETS UP IN
THURSDAY AFTERNOON ALLOWING WARM, MOIST AIR TO ADVECT INTO THE
AREA. THURSDAY NIGHT FINDS A STRONG COLD FRONT MOVING TOWARDS THE
FA WITH THUNDERSTORMS IN THE VICINITY OF THE FRONT. THE GFS, GEM,
NOGAPS AND DGEX ARE THE FASTEST WITH THE FRONT WHILE THE 00Z ECMWF
IS SLOWEST. TRIED TO LEAN MORE TOWARD THE ECMWF AS ALL MODELS ARE
TOO QUICK TO BREAK DOWN RIDGING DOWNSTREAM. THIS TREND CONTINUES
ON FRIDAY AND KEPT THE SAME APPROACH. LEFT SOME POPS OVER THE
EASTERN THIRD OF THE FA FRIDAY NIGHT AS PCPN MAY LINGER BEHIND THE
DEPARTING FRONT WITH THE CAA. A QUASI-ZONAL FLOW SETS UP SATURDAY
AND SUNDAY. A WEAK SHORT WAVE CLIPS THE EASTERN PORTION OF THE FA
SUNDAY AND HAVE SMALL POPS TO ACCOUNT FOR ITS PASSAGE.
&&
.POINT TEMPS/POPS...
DLH 63 42 52 39 / 10 20 60 20
INL 59 41 55 35 / 50 50 50 10
BRD 63 43 55 40 / 20 20 60 10
HYR 68 42 54 38 / 10 10 60 30
ASX 64 42 50 38 / 10 20 60 30
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...CANNON
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
636 AM CDT MON MAY 7 2012
.UPDATE...
UPDATED THE FORECAST TO REFLECT THE LATEST CLOUD AND FOG TRENDS.
IT APPEARS THICKER FOG HAS FORMED ALONG THE NORTH SHORE...SO
ALTERED THE MORNING FORECAST FROM PATCHY FOG TO AREAS OF FOG FOR
THAT AREA. ALSO...THE LATEST HRRR AND NAM RUNS SUGGEST MORE
EXTENSIVE CLOUD COVER MOVING IN FROM THE WEST TODAY...SO INCREASED
CLOUD COVER INTO THIS AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 627 AM CDT MON MAY 7 2012/
AVIATION...12Z TAFS.
DRY SLOT WORKING ITS WAY ACROSS THE AREA EARLY IN THE TAF CYCLE
WILL PRESENT A BRIEF WINDOW OF VFR. LIFR/IFR CIGS/VSBYS WITH
PATCHY BR/FOG AHEAD OF THE DRY SLOT WILL EXIT THE AREA FAIRLY
QUICKLY. BEHIND THE DRY SLOT...MVFR CIGS WILL SPREAD ACROSS THE
TAF SITES WITH SOME GUSTY SFC WINDS FROM 16Z TO 22Z. SOME SHOWERS
MAY OCCUR AFTER 21Z AS SFC LOW AND UPPER LOW DROP THROUGH THE
AREA. UPSTREAM SFC OBS INDICATE THE SHOWERS WILL BE ISOLD AND HAVE
VCSH TO ACCOUNT FOR THIS ISOLD NATURE.
PREV DISCUSSION... /ISSUED 337 AM CDT MON MAY 7 2012/
SHORT TERM...[NOW - TUESDAY]
AT 0830Z...THERE WAS A SURFACE LOW AND AN ASSOCIATED MID/UPPER
LEVEL LOW CENTERED OVER SOUTHERN SASKATCHEWAN. AN ASSOCIATED
OCCLUDED FRONT STRETCHED SOUTHEAST THROUGH THE WESTERN FA. MUCH OF
THE FA WAS COVERED WITH VERY LOW OVERCAST STRATUS...AND IN
ADDITION BKN/OVC HIGH CLOUDS COVERED THE SOUTHEASTERN FA. THERE
WAS SOME FOG ACROSS THE NORTHLAND...WITH SOME RECENT REPORTS NEAR
THE BRAINERD LAKES AND TWIN PORTS AREAS. THE WINDS WERE MOSTLY
CALM OR VERY LIGHT AND VARIABLE...EXCEPT FOR DEVELOPING LIGHT
SOUTHERLY WINDS ACROSS THE NORTHERN AND WESTERN FA. TEMPERATURES
WERE IN THE 40S TO LOW 50S. THE RADAR INDICATED LINGERING SHOWERS
ACROSS THE EASTERN FA...NAMELY THE ARROWHEAD.
EARLY THIS MORNING...THE OCCLUDED FRONT WILL CONTINUE TO MOVE
EASTWARD THROUGH THE FA...AND THE SHOWERS IN THE EASTERN FA WILL
GRADUALLY MOVE OUT OF THE FA. THE VERY LOW STRATUS AND PATCHY FOG
MAY LINGER THROUGH AT LEAST DAWN.
TODAY...THE SURFACE AND MID/UPPER LEVEL LOWS IN SOUTHERN
SASKATCHEWAN WILL MOVE INTO NORTHERN MINNESOTA. MIXING WILL
INCREASE THIS MORNING WITH THE INCREASING WESTERLY WINDS. THIS
SHOULD BEGIN TO BURN OFF THE EARLY MORNING STRATUS AND PATCHY
FOG...AS WELL AS GIVE THE FA SOME MORNING SUNSHINE. PATCHY FOG MAY
LINGER THROUGH PART OF THE MORNING ACROSS THE EASTERN FA WHERE THE
WINDS WILL BE LIGHTEST. THE COLD AIR ALOFT AND THE RELATIVELY LOW
CONVECTIVE TEMPERATURES TODAY SHOULD RESULT IN PLENTY OF CUMULUS
CLOUDS DEVELOPING BY THIS AFTERNOON. THE MODELS ARE IN GOOD
AGREEMENT THAT THE NORTHERN AND WESTERN FA COULD GET RAIN
SHOWERS. MODEL SUPPORT FOR INSTABILITY IS LIMITED...ABOUT 300 J/KG
OR LESS...BUT ENOUGH TO WARRANT INCLUDING A MENTION OF ISOLATED
THUNDER WITH THE SHOWERS. THE MORNING SUNSHINE SHOULD ALLOW
TEMPERATURES TO CLIMB TO THE LOWER 60S ACROSS MOST OF THE FA.
TONIGHT...THE SURFACE AND MID/UPPER TROUGH WILL MOVE
SOUTHEASTWARDS THROUGH THE FA. EXPECT A CLOUDY AND COOL NIGHT WITH
CONTINUING CHANCES OF RAIN SHOWERS...MAINLY ACROSS THE NORTHERN
HALF OF THE FA.
TUESDAY...THE NEGATIVELY TILTED MID/UPPER LEVEL TROUGH WILL SWING
THROUGH THE GREAT LAKES REGION THROUGH THE DAY ON TUESDAY AND THE
ASSOCIATED STACKED SURFACE LOW WILL SLIDE SOUTH TO SOUTHEASTERN
MINNESOTA BY TUESDAY EVENING. FORECAST SOUNDINGS ARE QUITE
SATURATED THROUGH THE MID LEVELS THROUGH THE DAY AND INTO THE
EVENING. AS THAT LOW PRESSURE CENTER SWINGS SOUTH...THE FA WILL
REMAIN CLOUDY AND WET...BUT COOLER THAN PREVIOUS DAY. THE
SOUNDINGS TUESDAY AFTERNOON ALSO SHOW SOME WEAK CAPE VALUES ACROSS
THE AREA AS THE AFTERNOON HEATING PICKS UP. HAVE INCLUDED ISOLATED
THUNDER TO ADDRESS THIS.
LONG TERM...[TUESDAY NIGHT - SUNDAY]
A LONG WAVE TROF WILL CLEAR THE FA TUESDAY EVENING WHILE ONE MORE
PIECE OF ENERGY DROPS QUICKLY INTO THE AREA BEHIND IT. THESE
FEATURES WARRANT THE POPS CURRENTLY IN PLACE OVER THE EASTERN TWO
THIRDS OF THE AREA TUESDAY EVENING. AFTER 06Z WEDNESDAY, UPPER
LEVEL AND SFC RIDGING BUILD INTO THE FA WITH A CLEARING SKY. THE
SFC RIDGING MOVES TO THE SOUTHERN GREAT LAKES WHILE UPPER RIDGING
REMAINS OVER THE FA THROUGH THURSDAY. A SW RETURN FLOW SETS UP IN
THURSDAY AFTERNOON ALLOWING WARM, MOIST AIR TO ADVECT INTO THE
AREA. THURSDAY NIGHT FINDS A STRONG COLD FRONT MOVING TOWARDS THE
FA WITH THUNDERSTORMS IN THE VICINITY OF THE FRONT. THE GFS, GEM,
NOGAPS AND DGEX ARE THE FASTEST WITH THE FRONT WHILE THE 00Z ECMWF
IS SLOWEST. TRIED TO LEAN MORE TOWARD THE ECMWF AS ALL MODELS ARE
TOO QUICK TO BREAK DOWN RIDGING DOWNSTREAM. THIS TREND CONTINUES
ON FRIDAY AND KEPT THE SAME APPROACH. LEFT SOME POPS OVER THE
EASTERN THIRD OF THE FA FRIDAY NIGHT AS PCPN MAY LINGER BEHIND THE
DEPARTING FRONT WITH THE CAA. A QUASI-ZONAL FLOW SETS UP SATURDAY
AND SUNDAY. A WEAK SHORT WAVE CLIPS THE EASTERN PORTION OF THE FA
SUNDAY AND HAVE SMALL POPS TO ACCOUNT FOR ITS PASSAGE.
&&
.POINT TEMPS/POPS...
DLH 61 42 52 39 / 20 20 60 20
INL 61 41 55 35 / 40 50 50 10
BRD 63 43 55 40 / 20 20 60 10
HYR 67 42 54 38 / 10 10 60 30
ASX 64 42 50 38 / 10 20 60 30
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...GROCHOCINSKI
LONG TERM....GSF
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1213 PM CDT MON MAY 7 2012
.AVIATION...18Z TAF. GENERALLY QUIET WEATHER WITH VFR CONDITIONS
ARE EXPECTED FOR THIS TAF PERIOD. COULD SEE A FEW SPRINKLES MOVE
INTO THE AREA...ASSOCIATED WITH AN AREA OF LIGHT RAIN SHIFTING
NORTHEAST OUT OF KANSAS...SO LEFT VCSH MENTION GOING THIS
AFTERNOON. EVEN IF THE TERMINAL AREA DOES SEE PRECIP...CLOUD
BASES ARE EXPECTED TO REMAIN IN THE MID/UPPER LEVELS. WITH SURFACE
HIGH PRESSURE SET UP TO THE WEST THROUGH THE TAF PERIOD...WIND
DIRECTION EXPECTED TO REMAIN PRIMARILY NORTHWESTERLY. SHOULD START
TO SEE DIMINISHING SPEEDS LATER THIS AFTERNOON AND THOUGH THE
OVERNIGHT HOURS...BEFORE BECOMING A BIT MORE GUSTY TOWARD THE END
OF THE TAF PERIOD.
&&
PREV DISCUSSION... /ISSUED 416 AM CDT MON MAY 7 2012/
SHORT TERM...CERTAINLY QUITE A CHANGE FROM THE PAST WEEK...WHICH
WAS MORE LIKE JULY WITH HIGH HUMIDITY AND SEVERAL EPISODES OF SEVERE
THUNDERSTORMS WITH LARGE HAIL. WE NOW HAVE SUB-40 DEGREE DEWPOINTS
WORKING INTO CENTRAL NEBRASKA FROM THE NORTHWEST ABOUT
NORTH/NORTHWEST WINDS. TEMPERATURES HAVE REMAINED UP A BIT TONIGHT
WITH COLD ADVECTION THANKS TO GOOD DECK OF MID/HIGH CLOUDS.
THE MAIN ISSUE TODAY IS A SMALL RISK FOR SPRINKLES IN SOME AREA...AND
THEN SOME CONCERN OF PATCHY FROST OVER THE NORTHWEST FORECAST AREA
TONIGHT. THOUGH LOW LEVEL DRY AIR WILL DEEPEN WITH TIME...THE FORECAST
AREA ASCENDS INTO A FAVORABLE RIGHT REAR QUADRANT OF 250MB JET STREAK
BY AFTERNOON. THIS FRONTOGENETIC TYPE FORCING IS CAPTIONED ON AT
LEAST A FEW MODELS...INCLUDING THE RUC RAPID REFRESH...WITH HINTS OF
MOISTURE TRYING TO SPILL NORTHEAST FROM COLORADO. BELIEVE ITS WORTH
A SPRINKLE MENTION AT THIS TIME FOR AREAS SOUTH OF INTERSTATE 80.
CHILLY CONDITIONS TONIGHT ARE MOST LIKELY IN THE NORTHWEST FORECAST
AREA...MAINLY NORTHWEST OF A LINE FROM ELWOOD...TO LOUP CITY...TO
GREELEY. AIR WILL BE DRY ENOUGH...WINDS PROBABLY LIGHT ENOUGH...TO
REACH NEAR THE 36 DEGREE LINE OR LOWER...WHICH WOULD SUPPORT FROST.
THE ISSUE MAY BE CLOUDS...AS SOME INCREASE/LINGERING CLOUDS COULD
REEK HAVOC WITH JUST WHAT AREAS ACTUALLY DROP THE LOWEST. WILL
MENTION SOME PATCHY FROST IN THE GOTHENBURG AREA...AND IN THE
HAZARDOUS WEATHER OUTLOOK...BUT NOT CONFIDENT ENOUGH TO ISSUE ANY
ADVISORY AT THIS TIME.
DESPITE SUNSHINE...A COOL START WILL LEAD TO A COOLISH DAY TUESDAY.
NORTH/NORTHWEST WINDS WILL KEEP THAT COOL FEEL IN THE AIR EVEN WITH
TEMPERATURES IN THE UPPER 60S TO LOWER 70S. THE WINDS WILL BE
STRONGEST ACROSS SOUTH CENTRAL NEBRASKA...AND GRADUALLY DROP OFF
THE FURTHER SOUTH ONE GOES. WITH HIGH PRESSURE SETTLING RIGHT ON THE
FORECAST TUESDAY NIGHT...ANOTHER RISK FOR PATCHY FROST COULD ARISE.
THAT APPEARS MOSTLY LIKELY IN THE NORTHEAST FORECAST AREA...MAINLY
NORTH AND EAST OF A YORK TO GREELEY LINE. THE WESTERN AREAS WILL
SEE JUST EVEN SOUTHERLY FLOW TO LIMIT COOLING IN THOSE AREAS.
WEDNESDAY AND WEDNESDAY WILL BE NICE WITH MAINLY CLEAR SKIES AND
SOUTHERLY FLOW GRADUALLY DEVELOPING THROUGHOUT THE DAY FROM WEST
TO EAST. HIGHS WEDNESDAY WILL BE RIGHT WHERE SHOULD BE FOR THIS
TIME OF YEAR...IN THE LOWER 70S.
LONG TERM...THURSDAY THROUGH SUNDAY. NEEDLESS TO SAY...IT LOOKS
LIKE THE MONTH OF MAY GOT ITS FIRST MULTI-DAY BOUT OF SEVERE WEATHER
OUT OF THE WAY QUITE EARLY...AS THERE ARE NO SYNOPTICALLY EVIDENT
THREATS FOR WIDESPREAD STRONG-SEVERE STORMS THROUGH AT LEAST THE
NEXT 7-9 DAYS PER THE LATEST 00Z GFS/ECMWF RUNS. THAT BEING
SAID...THERE ARE SOME CHANCES FOR SHOWERS/GENERALLY WEAK STORMS.
TEMP WISE...THESE 4 DAYS WILL GENERALLY BOUNCE AROUND WITHIN ROUGHLY
5 DEGREES EITHER SIDE OF NORMAL FOR MID-MAY.
STARTING OFF THURSDAY...THIS IS LOOKING LIKE THE WARMEST DAY OF
THE EXTENDED...AND NUDGED UP HIGHS VERY SLIGHTLY FROM PREVIOUS
FORECAST...PUTTING MOST AREAS IN THE 78-82 RANGE. IN THE MID-UPPER
LEVELS...THE TWO MAIN FEATURES ARE A COMPACT...CUT OFF LOW SLOWLY
MOVING INTO TX...AND A LARGER SCALE SHORTWAVE TROUGH CROSSING THE
NORTHERN ROCKIES. IN RESPONSE TO THE LATTER...HIGH PLAINS SURFACE
PRESSURE FALLS WILL INDUCE SOUTHERLY WINDS DURING THE DAY...AND
LIKELY A BIT BREEZY WITH SUSTAINED SPEEDS EASILY 15-20 MPH.
THURSDAY NIGHT...MODELS ARE IN DECENT AGREEMENT DRAGGING THE 500MB
SHORTWAVE TROUGH ALONG THE CANADIAN BORDER INTO THE ND AREA...AND
PUSHING A WELL-DEFINED SURFACE COLD FRONT SOUTHWARD INTO THE
REGION. AT THIS TIME...THE GFS IS A BIT FASTER/STRONGER WITH THIS
WAVE AND RESULTANT FRONTAL PASSAGE THAN THE ECMWF...AND DEVELOPS A
BAND OF PRECIP MAINLY ACROSS WESTERN NEB DURING THE NIGHT WITHIN
THE ENTRANCE REGION OF THE UPPER JET AND JUST BEHIND THE SURFACE
FRONT. ALTHOUGH ECMWF KEEPS ALL PRECIP NORTHWEST OF THE CWA
THROUGH THE NIGHT...WILL PLAY IT CLOSER TO PREVIOUS FORECAST AND
THE GFS SOLUTION WITH JUST A SLIGHT CHANCE OF SHOWERS/ISOLATED
STORMS ACROSS FAR NORTHWEST COUNTIES. INSTABILITY PROGS INDICATE
THAT EVEN A FEW HUNDRED J/KG OF ELEVATED CAPE MAY BE HARD TO COME
BY...SO AT THIS POINT WOULD THINK SMALL HAIL WOULD BE THE MOST ANY
STORMS COULD GENERATE.
FRIDAY INTO FRIDAY NIGHT...MODEL AGREEMENT REMAINS REASONABLY HIGH
FOR THIS TIME RANGE...AS THE NORTHERN SHORTWAVE CONTINUES TRACKING
TOWARD THE GREAT LAKES...AND THE SURFACE COLD FRONT PUSHES WELL
SOUTH THROUGH THE CWA. WELL OFF TO THE SOUTH...THE SLOW MOVING TX
MID-UPPER LOW SHOULD KEEP APPRECIABLE LOW LEVEL MOISTURE/INSTABILITY
WELL SOUTH OF THE CENTRAL PLAINS. THAT BEING SAID...MID LEVEL
SATURATION WITHIN THE ENTRANCE REGION OF THE UPPER JET SHOULD KEEP
AT LEAST THE POTENTIAL FOR RAIN SHOWERS GOING...AND HAVE 20-30
PERCENT CHANCES CWA-WIDE. DESPITE MEAGER INSTABILITY...WILL
MAINTAIN THUNDER WORDING BUT WILL KEEP IT AS ISOLATED AND WITH
SEEMINGLY VERY LITTLE RISK OF STRONG/SEVERE. TEMP-WISE...HIGHS
FRIDAY WILL BE A BIT TRICKY AS THE FRONT PUSHES IN...BUT WILL AIM
FOR MID 60S NORTHWEST TO MID 70S SOUTHEAST. HAVE FRIDAY NIGHT LOWS
WELL DOWN IN THE 40S ACROSS THE NORTHWEST 1/2 OF THE CWA.
SATURDAY INTO SATURDAY NIGHT...KEPT SLIGHT CHANCE POPS FOR MAINLY
LIGHT RAIN SHOWERS GOING...BUT PRIMARILY NEAR AND SOUTH OF THE
STATE LINE. LOWERED HIGHS FOR SATURDAY SLIGHTLY PER ALLBLEND MODEL
CONSENSUS...WITH ONLY MID-UPPER 60S CWA-WIDE. A SEASONABLY COOL
NIGHT FOLLOWS WITH MID-UPPER 40S CWA-WIDE.
FINALLY FOR SUNDAY...KEPT 20-30 POPS GOING ACROSS SOUTHERN
ZONES...BUT MODEL AGREEMENT HAS ALREADY FADED BY THEN...WITH GFS
KEEPING IT DRY...WHILE ECMWF BRINGS A BROAD MID LEVEL WAVE INTO
THE REGION IN DISORGANIZED NORTHWEST FLOW...BUT WITH BETTER PRECIP
CHANCES PRESUMABLY FOCUSING IN MORE FAVORED UPSLOPE AREAS TO THE
WEST. WILL AIM FOR LOW 70S CWA-WIDE FOR HIGH TEMPS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
559 AM CDT MON MAY 7 2012
.AVIATION...12Z KGRI TAF. VFR CEILING/VISIBILITY ARE FORECAST
THROUGH THE PERIOD...ALTHOUGH THE WEATHER WON`T NECESSARILY BE
COMPLETELY INACTIVE. A FAIRLY SOLID MID LEVEL CLOUD DECK WILL
DOMINATE MOST OF THE PERIOD...AND THERE ARE INCREASING SIGNS THAT
SPRINKLES OR A FEW PASSING LIGHT RAIN SHOWERS WILL AFFECT THE AREA
MAINLY DURING THE FIRST 12 HOURS. WILL FOREGO ANY PREVAILING OR
TEMPO PRECIPITATION GROUPS AT THIS TIME...BUT WILL INSERT A
VICINITY SHOWER MENTION. OTHERWISE...SURFACE WINDS WILL PREVAIL
FROM A NORTHWESTERLY DIRECTION THROUGH THE MAJORITY OF THE
PERIOD...WITH A BIT OF GUSTINESS FOR MUCH OF THE DAY WITH GUST
POTENTIAL TO AROUND 24KT BEFORE SUBSIDING FOR THE OVERNIGHT HOURS.
&&
.PREV DISCUSSION... /ISSUED 416 AM CDT MON MAY 7 2012/
SHORT TERM...CERTAINLY QUITE A CHANGE FROM THE PAST WEEK...WHICH
WAS MORE LIKE JULY WITH HIGH HUMIDITY AND SEVERAL EPISODES OF SEVERE
THUNDERSTORMS WITH LARGE HAIL. WE NOW HAVE SUB-40 DEGREE DEWPOINTS
WORKING INTO CENTRAL NEBRASKA FROM THE NORTHWEST ABOUT
NORTH/NORTHWEST WINDS. TEMPERATURES HAVE REMAINED UP A BIT TONIGHT
WITH COLD ADVECTION THANKS TO GOOD DECK OF MID/HIGH CLOUDS.
THE MAIN ISSUE TODAY IS A SMALL RISK FOR SPRINKLES IN SOME AREA...AND
THEN SOME CONCERN OF PATCHY FROST OVER THE NORTHWEST FORECAST AREA
TONIGHT. THOUGH LOW LEVEL DRY AIR WILL DEEPEN WITH TIME...THE FORECAST
AREA ASCENDS INTO A FAVORABLE RIGHT REAR QUADRANT OF 250MB JET STREAK
BY AFTERNOON. THIS FRONTOGENETIC TYPE FORCING IS CAPTIONED ON AT
LEAST A FEW MODELS...INCLUDING THE RUC RAPID REFRESH...WITH HINTS OF
MOISTURE TRYING TO SPILL NORTHEAST FROM COLORADO. BELIEVE ITS WORTH
A SPRINKLE MENTION AT THIS TIME FOR AREAS SOUTH OF INTERSTATE 80.
CHILLY CONDITIONS TONIGHT ARE MOST LIKELY IN THE NORTHWEST FORECAST
AREA...MAINLY NORTHWEST OF A LINE FROM ELWOOD...TO LOUP CITY...TO
GREELEY. AIR WILL BE DRY ENOUGH...WINDS PROBABLY LIGHT ENOUGH...TO
REACH NEAR THE 36 DEGREE LINE OR LOWER...WHICH WOULD SUPPORT FROST.
THE ISSUE MAY BE CLOUDS...AS SOME INCREASE/LINGERING CLOUDS COULD
REEK HAVOC WITH JUST WHAT AREAS ACTUALLY DROP THE LOWEST. WILL
MENTION SOME PATCHY FROST IN THE GOTHENBURG AREA...AND IN THE
HAZARDOUS WEATHER OUTLOOK...BUT NOT CONFIDENT ENOUGH TO ISSUE ANY
ADVISORY AT THIS TIME.
DESPITE SUNSHINE...A COOL START WILL LEAD TO A COOLISH DAY TUESDAY.
NORTH/NORTHWEST WINDS WILL KEEP THAT COOL FEEL IN THE AIR EVEN WITH
TEMPERATURES IN THE UPPER 60S TO LOWER 70S. THE WINDS WILL BE
STRONGEST ACROSS SOUTH CENTRAL NEBRASKA...AND GRADUALLY DROP OFF
THE FURTHER SOUTH ONE GOES. WITH HIGH PRESSURE SETTLING RIGHT ON THE
FORECAST TUESDAY NIGHT...ANOTHER RISK FOR PATCHY FROST COULD ARISE.
THAT APPEARS MOSTLY LIKELY IN THE NORTHEAST FORECAST AREA...MAINLY
NORTH AND EAST OF A YORK TO GREELEY LINE. THE WESTERN AREAS WILL
SEE JUST EVEN SOUTHERLY FLOW TO LIMIT COOLING IN THOSE AREAS.
WEDNESDAY AND WEDNESDAY WILL BE NICE WITH MAINLY CLEAR SKIES AND
SOUTHERLY FLOW GRADUALLY DEVELOPING THROUGHOUT THE DAY FROM WEST
TO EAST. HIGHS WEDNESDAY WILL BE RIGHT WHERE SHOULD BE FOR THIS
TIME OF YEAR...IN THE LOWER 70S.
LONG TERM...THURSDAY THROUGH SUNDAY. NEEDLESS TO SAY...IT LOOKS
LIKE THE MONTH OF MAY GOT ITS FIRST MULTI-DAY BOUT OF SEVERE WEATHER
OUT OF THE WAY QUITE EARLY...AS THERE ARE NO SYNOPTICALLY EVIDENT
THREATS FOR WIDESPREAD STRONG-SEVERE STORMS THROUGH AT LEAST THE
NEXT 7-9 DAYS PER THE LATEST 00Z GFS/ECMWF RUNS. THAT BEING
SAID...THERE ARE SOME CHANCES FOR SHOWERS/GENERALLY WEAK STORMS.
TEMP WISE...THESE 4 DAYS WILL GENERALLY BOUNCE AROUND WITHIN ROUGHLY
5 DEGREES EITHER SIDE OF NORMAL FOR MID-MAY.
STARTING OFF THURSDAY...THIS IS LOOKING LIKE THE WARMEST DAY OF
THE EXTENDED...AND NUDGED UP HIGHS VERY SLIGHTLY FROM PREVIOUS
FORECAST...PUTTING MOST AREAS IN THE 78-82 RANGE. IN THE MID-UPPER
LEVELS...THE TWO MAIN FEATURES ARE A COMPACT...CUT OFF LOW SLOWLY
MOVING INTO TX...AND A LARGER SCALE SHORTWAVE TROUGH CROSSING THE
NORTHERN ROCKIES. IN RESPONSE TO THE LATTER...HIGH PLAINS SURFACE
PRESSURE FALLS WILL INDUCE SOUTHERLY WINDS DURING THE DAY...AND
LIKELY A BIT BREEZY WITH SUSTAINED SPEEDS EASILY 15-20 MPH.
THURSDAY NIGHT...MODELS ARE IN DECENT AGREEMENT DRAGGING THE 500MB
SHORTWAVE TROUGH ALONG THE CANADIAN BORDER INTO THE ND AREA...AND
PUSHING A WELL-DEFINED SURFACE COLD FRONT SOUTHWARD INTO THE
REGION. AT THIS TIME...THE GFS IS A BIT FASTER/STRONGER WITH THIS
WAVE AND RESULTANT FRONTAL PASSAGE THAN THE ECMWF...AND DEVELOPS A
BAND OF PRECIP MAINLY ACROSS WESTERN NEB DURING THE NIGHT WITHIN
THE ENTRANCE REGION OF THE UPPER JET AND JUST BEHIND THE SURFACE
FRONT. ALTHOUGH ECMWF KEEPS ALL PRECIP NORTHWEST OF THE CWA
THROUGH THE NIGHT...WILL PLAY IT CLOSER TO PREVIOUS FORECAST AND
THE GFS SOLUTION WITH JUST A SLIGHT CHANCE OF SHOWERS/ISOLATED
STORMS ACROSS FAR NORTHWEST COUNTIES. INSTABILITY PROGS INDICATE
THAT EVEN A FEW HUNDRED J/KG OF ELEVATED CAPE MAY BE HARD TO COME
BY...SO AT THIS POINT WOULD THINK SMALL HAIL WOULD BE THE MOST ANY
STORMS COULD GENERATE.
FRIDAY INTO FRIDAY NIGHT...MODEL AGREEMENT REMAINS REASONABLY HIGH
FOR THIS TIME RANGE...AS THE NORTHERN SHORTWAVE CONTINUES TRACKING
TOWARD THE GREAT LAKES...AND THE SURFACE COLD FRONT PUSHES WELL
SOUTH THROUGH THE CWA. WELL OFF TO THE SOUTH...THE SLOW MOVING TX
MID-UPPER LOW SHOULD KEEP APPRECIABLE LOW LEVEL MOISTURE/INSTABILITY
WELL SOUTH OF THE CENTRAL PLAINS. THAT BEING SAID...MID LEVEL
SATURATION WITHIN THE ENTRANCE REGION OF THE UPPER JET SHOULD KEEP
AT LEAST THE POTENTIAL FOR RAIN SHOWERS GOING...AND HAVE 20-30
PERCENT CHANCES CWA-WIDE. DESPITE MEAGER INSTABILITY...WILL
MAINTAIN THUNDER WORDING BUT WILL KEEP IT AS ISOLATED AND WITH
SEEMINGLY VERY LITTLE RISK OF STRONG/SEVERE. TEMP-WISE...HIGHS
FRIDAY WILL BE A BIT TRICKY AS THE FRONT PUSHES IN...BUT WILL AIM
FOR MID 60S NORTHWEST TO MID 70S SOUTHEAST. HAVE FRIDAY NIGHT LOWS
WELL DOWN IN THE 40S ACROSS THE NORTHWEST 1/2 OF THE CWA.
SATURDAY INTO SATURDAY NIGHT...KEPT SLIGHT CHANCE POPS FOR MAINLY
LIGHT RAIN SHOWERS GOING...BUT PRIMARILY NEAR AND SOUTH OF THE
STATE LINE. LOWERED HIGHS FOR SATURDAY SLIGHTLY PER ALLBLEND MODEL
CONSENSUS...WITH ONLY MID-UPPER 60S CWA-WIDE. A SEASONABLY COOL
NIGHT FOLLOWS WITH MID-UPPER 40S CWA-WIDE.
FINALLY FOR SUNDAY...KEPT 20-30 POPS GOING ACROSS SOUTHERN
ZONES...BUT MODEL AGREEMENT HAS ALREADY FADED BY THEN...WITH GFS
KEEPING IT DRY...WHILE ECMWF BRINGS A BROAD MID LEVEL WAVE INTO
THE REGION IN DISORGANIZED NORTHWEST FLOW...BUT WITH BETTER PRECIP
CHANCES PRESUMABLY FOCUSING IN MORE FAVORED UPSLOPE AREAS TO THE
WEST. WILL AIM FOR LOW 70S CWA-WIDE FOR HIGH TEMPS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...MORITZ
LONG TERM/AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS HASTINGS NE
416 AM CDT MON MAY 7 2012
.SHORT TERM...CERTAINLY QUITE A CHANGE FROM THE PAST WEEK...WHICH
WAS MORE LIKE JULY WITH HIGH HUMIDITY AND SEVERAL EPISODES OF SEVERE
THUNDERSTORMS WITH LARGE HAIL. WE NOW HAVE SUB-40 DEGREE DEWPOINTS
WORKING INTO CENTRAL NEBRASKA FROM THE NORTHWEST ABOUT
NORTH/NORTHWEST WINDS. TEMPERATURES HAVE REMAINED UP A BIT TONIGHT
WITH COLD ADVECTION THANKS TO GOOD DECK OF MID/HIGH CLOUDS.
THE MAIN ISSUE TODAY IS A SMALL RISK FOR SPRINKLES IN SOME AREA...AND
THEN SOME CONCERN OF PATCHY FROST OVER THE NORTHWEST FORECAST AREA
TONIGHT. THOUGH LOW LEVEL DRY AIR WILL DEEPEN WITH TIME...THE FORECAST
AREA ASCENDS INTO A FAVORABLE RIGHT REAR QUADRANT OF 250MB JET STREAK
BY AFTERNOON. THIS FRONTOGENETIC TYPE FORCING IS CAPTIONED ON AT
LEAST A FEW MODELS...INCLUDING THE RUC RAPID REFRESH...WITH HINTS OF
MOISTURE TRYING TO SPILL NORTHEAST FROM COLORADO. BELIEVE ITS WORTH
A SPRINKLE MENTION AT THIS TIME FOR AREAS SOUTH OF INTERSTATE 80.
CHILLY CONDITIONS TONIGHT ARE MOST LIKELY IN THE NORTHWEST FORECAST
AREA...MAINLY NORTHWEST OF A LINE FROM ELWOOD...TO LOUP CITY...TO
GREELEY. AIR WILL BE DRY ENOUGH...WINDS PROBABLY LIGHT ENOUGH...TO
REACH NEAR THE 36 DEGREE LINE OR LOWER...WHICH WOULD SUPPORT FROST.
THE ISSUE MAY BE CLOUDS...AS SOME INCREASE/LINGERING CLOUDS COULD
REEK HAVOC WITH JUST WHAT AREAS ACTUALLY DROP THE LOWEST. WILL
MENTION SOME PATCHY FROST IN THE GOTHENBURG AREA...AND IN THE
HAZARDOUS WEATHER OUTLOOK...BUT NOT CONFIDENT ENOUGH TO ISSUE ANY
ADVISORY AT THIS TIME.
DESPITE SUNSHINE...A COOL START WILL LEAD TO A COOLISH DAY TUESDAY.
NORTH/NORTHWEST WINDS WILL KEEP THAT COOL FEEL IN THE AIR EVEN WITH
TEMPERATURES IN THE UPPER 60S TO LOWER 70S. THE WINDS WILL BE
STRONGEST ACROSS SOUTH CENTRAL NEBRASKA...AND GRADUALLY DROP OFF
THE FURTHER SOUTH ONE GOES. WITH HIGH PRESSURE SETTLING RIGHT ON THE
FORECAST TUESDAY NIGHT...ANOTHER RISK FOR PATCHY FROST COULD ARISE.
THAT APPEARS MOSTLY LIKELY IN THE NORTHEAST FORECAST AREA...MAINLY
NORTH AND EAST OF A YORK TO GREELEY LINE. THE WESTERN AREAS WILL
SEE JUST EVEN SOUTHERLY FLOW TO LIMIT COOLING IN THOSE AREAS.
WEDNESDAY AND WEDNESDAY WILL BE NICE WITH MAINLY CLEAR SKIES AND
SOUTHERLY FLOW GRADUALLY DEVELOPING THROUGHOUT THE DAY FROM WEST
TO EAST. HIGHS WEDNESDAY WILL BE RIGHT WHERE SHOULD BE FOR THIS
TIME OF YEAR...IN THE LOWER 70S. MORITZ
.LONG TERM...THURSDAY THROUGH SUNDAY. NEEDLESS TO SAY...IT LOOKS
LIKE THE MONTH OF MAY GOT ITS FIRST MULTI-DAY BOUT OF SEVERE WEATHER
OUT OF THE WAY QUITE EARLY...AS THERE ARE NO SYNOPTICALLY EVIDENT
THREATS FOR WIDESPREAD STRONG-SEVERE STORMS THROUGH AT LEAST THE
NEXT 7-9 DAYS PER THE LATEST 00Z GFS/ECMWF RUNS. THAT BEING
SAID...THERE ARE SOME CHANCES FOR SHOWERS/GENERALLY WEAK STORMS.
TEMP WISE...THESE 4 DAYS WILL GENERALLY BOUNCE AROUND WITHIN ROUGHLY
5 DEGREES EITHER SIDE OF NORMAL FOR MID-MAY.
STARTING OFF THURSDAY...THIS IS LOOKING LIKE THE WARMEST DAY OF
THE EXTENDED...AND NUDGED UP HIGHS VERY SLIGHTLY FROM PREVIOUS
FORECAST...PUTTING MOST AREAS IN THE 78-82 RANGE. IN THE MID-UPPER
LEVELS...THE TWO MAIN FEATURES ARE A COMPACT...CUT OFF LOW SLOWLY
MOVING INTO TX...AND A LARGER SCALE SHORTWAVE TROUGH CROSSING THE
NORTHERN ROCKIES. IN RESPONSE TO THE LATTER...HIGH PLAINS SURFACE
PRESSURE FALLS WILL INDUCE SOUTHERLY WINDS DURING THE DAY...AND
LIKELY A BIT BREEZY WITH SUSTAINED SPEEDS EASILY 15-20 MPH.
THURSDAY NIGHT...MODELS ARE IN DECENT AGREEMENT DRAGGING THE 500MB
SHORTWAVE TROUGH ALONG THE CANADIAN BORDER INTO THE ND AREA...AND
PUSHING A WELL-DEFINED SURFACE COLD FRONT SOUTHWARD INTO THE
REGION. AT THIS TIME...THE GFS IS A BIT FASTER/STRONGER WITH THIS
WAVE AND RESULTANT FRONTAL PASSAGE THAN THE ECMWF...AND DEVELOPS A
BAND OF PRECIP MAINLY ACROSS WESTERN NEB DURING THE NIGHT WITHIN
THE ENTRANCE REGION OF THE UPPER JET AND JUST BEHIND THE SURFACE
FRONT. ALTHOUGH ECMWF KEEPS ALL PRECIP NORTHWEST OF THE CWA
THROUGH THE NIGHT...WILL PLAY IT CLOSER TO PREVIOUS FORECAST AND
THE GFS SOLUTION WITH JUST A SLIGHT CHANCE OF SHOWERS/ISOLATED
STORMS ACROSS FAR NORTHWEST COUNTIES. INSTABILITY PROGS INDICATE
THAT EVEN A FEW HUNDRED J/KG OF ELEVATED CAPE MAY BE HARD TO COME
BY...SO AT THIS POINT WOULD THINK SMALL HAIL WOULD BE THE MOST ANY
STORMS COULD GENERATE.
FRIDAY INTO FRIDAY NIGHT...MODEL AGREEMENT REMAINS REASONABLY HIGH
FOR THIS TIME RANGE...AS THE NORTHERN SHORTWAVE CONTINUES TRACKING
TOWARD THE GREAT LAKES...AND THE SURFACE COLD FRONT PUSHES WELL
SOUTH THROUGH THE CWA. WELL OFF TO THE SOUTH...THE SLOW MOVING TX
MID-UPPER LOW SHOULD KEEP APPRECIABLE LOW LEVEL MOISTURE/INSTABILITY
WELL SOUTH OF THE CENTRAL PLAINS. THAT BEING SAID...MID LEVEL
SATURATION WITHIN THE ENTRANCE REGION OF THE UPPER JET SHOULD KEEP
AT LEAST THE POTENTIAL FOR RAIN SHOWERS GOING...AND HAVE 20-30
PERCENT CHANCES CWA-WIDE. DESPITE MEAGER INSTABILITY...WILL
MAINTAIN THUNDER WORDING BUT WILL KEEP IT AS ISOLATED AND WITH
SEEMINGLY VERY LITTLE RISK OF STRONG/SEVERE. TEMP-WISE...HIGHS
FRIDAY WILL BE A BIT TRICKY AS THE FRONT PUSHES IN...BUT WILL AIM
FOR MID 60S NORTHWEST TO MID 70S SOUTHEAST. HAVE FRIDAY NIGHT LOWS
WELL DOWN IN THE 40S ACROSS THE NORTHWEST 1/2 OF THE CWA.
SATURDAY INTO SATURDAY NIGHT...KEPT SLIGHT CHANCE POPS FOR MAINLY
LIGHT RAIN SHOWERS GOING...BUT PRIMARILY NEAR AND SOUTH OF THE
STATE LINE. LOWERED HIGHS FOR SATURDAY SLIGHTLY PER ALLBLEND MODEL
CONSENSUS...WITH ONLY MID-UPPER 60S CWA-WIDE. A SEASONABLY COOL
NIGHT FOLLOWS WITH MID-UPPER 40S CWA-WIDE.
FINALLY FOR SUNDAY...KEPT 20-30 POPS GOING ACROSS SOUTHERN
ZONES...BUT MODEL AGREEMENT HAS ALREADY FADED BY THEN...WITH GFS
KEEPING IT DRY...WHILE ECMWF BRINGS A BROAD MID LEVEL WAVE INTO
THE REGION IN DISORGANIZED NORTHWEST FLOW...BUT WITH BETTER PRECIP
CHANCES PRESUMABLY FOCUSING IN MORE FAVORED UPSLOPE AREAS TO THE
WEST. WILL AIM FOR LOW 70S CWA-WIDE FOR HIGH TEMPS. PFANNKUCH
&&
.PREV DISCUSSION... /ISSUED 1050 PM CDT SUN MAY 6 2012/
UPDATE...UPDATED THE FORECAST TONIGHT TO INCREASE SKY COVER AND
LOWER DEW POINTS...AND ALSO TO HOLD ON TO THE LINGERING SHOWERS IN
THE SOUTHEAST LONGER TONIGHT.
AVIATION...06Z KGRI TAF. WIND WILL BE THE BIGGEST ISSUE FOR THIS
FORECAST. NORTH WIND WILL PICK BACK UP AGAIN FOR MONDAY BY MID-
MORNING AS LOW-LEVEL LAPSE RATES INCREASE. THERE SHOULD BE A
CONSIDERABLE AMOUNT OF MID-LEVEL CLOUDINESS HANGING AROUND FOR
MOST IF NOT ALL OF THIS FORECAST. ANY SHOWER ACTIVITY SHOULD
REMAIN SOUTHEAST OF THE TERMINAL TONIGHT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1153 PM CDT SUN MAY 6 2012
.AVIATION...
06Z TAFS FOR KOFK...KOMA AND KLNK.
DRIER DEWPOINTS ARE MOVING IN FROM THE NORTH WITH VFR CONDTIONS
AND VARIABLE MID AND HIGH LEVEL CLOUDS THROUGH THE TAF PERIOD.
THERE IS A STORM SYSTEM OVER THE SOUTHWEST U.S. AND SHOULD LEAD TO
SOME THICKENING MID LEVEL CLOUDS MONDAY. THERE ARE SOME MODEL
DIFFERENCES ON HOW STRONG THE MOISTURE RETURN WILL BE. IF IT WILL
BE JUST CLOUDS OR POSSIBLY SOME LIGHT PRECIP. SO THIS WILL NEED TO
BE MONITORED. NORTH WINDS TONIGHT AT 5 TO 15KT WILL INCREASE AFTER
15Z TO 15 TO 20KTS WITH GUSTS TO 25KT DURING THE DAY MONDAY.
&&
.PREV DISCUSSION... /ISSUED 315 PM CDT SUN MAY 6 2012/
SHORT TERM...TONIGHT
UPPER AIR CHARTS FROM 12Z SHOWED THE FOLLOWING. AT 300 MB...PRIMARY
JETSTREAM STRETCHED FROM UTAH INTO ONTARIO WITH A JET MAX OF AROUND
90-100 KNOTS OVER NORTH DAKOTA. AT 500 MB...A FAIRLY TIGHT/COMPACT
CLOSED LOW WAS NOTED NEAR KGGW...CLOSE TO THE BORDER OF MONTANA AND
SASKATCHEWAN. 12 HOUR 500 MB HEIGHT FALL AT KGGW WAS 110 METERS BUT
THE ESTIMATED MAX VALUE WAS ABOUT 140 METERS A LITTLE FARTHER NORTH.
MODEST SOUTHWESTERLY FLOW WAS NOTED FROM THE DESERT SOUTHWEST INTO
THE NORTHERN PLAINS. DECENT MOISTURE WAS IN PLACE AT 850 MB...WITH
DEWPOINTS IN THE TEENS FROM KANSAS INTO ILLINOIS. AT THE SURFACE...
AN OCCLUDED FRONT CURVED FROM LOW PRESSURE OVER SASKATCHWAN INTO
MINNESOTA...THEN A COLD FRONT TRAILED SOUTH THROUGH WESTERN IOWA...
AND DOWN INTO WESTERN OKLAHOMA. SURFACE PATTERN ACROSS SOUTHEAST
NEBRASKA WAS SOMEWHAT AFFECTED/CONTAMINATED BY EARLIER MCS THAT
PRODUCED OUTFLOW.
ALTHOUGH THE MAIN SURFACE FRONT WILL CONTINUE TO PUSH SOUTHEAST OR
EAST TONIGHT...THERE IS STILL ENOUGH LINGERING ELEVATED MOISTURE AND
INSTABILITY OVER ABOUT THE SOUTHEASTERN 1/2 OF THE FORECAST AREA FOR
SCATTERED THUNDERSTORMS AT LEAST THROUGH MIDNIGHT. THIS IS CLOSER
TO THE 850 MB FRONT. 12Z NAM WAS MORE A BIT MORE AGRESSIVE WITH
PRECIPITATION COMPARED TO THE GFS. 17Z RUN OF THE HRRR THOUGH
SUGGESTED 12Z NAM WAS REASONABLE.
LONG TERM...MONDAY THROUGH SUNDAY.
TEMPERATURES WILL PROVIDE THE MAIN CHALLENGES THROUGH MUCH OF THE
WEEK WITH HIGHER CHANCES FOR SHOWERS/THUNDERSTORMS NOT ARRIVING
UNTIL ABOUT FRIDAY.
CLOSED LOW AT 500 MB WILL TRACK EASTWARD JUST NORTH OF THE BORDER OF
THE U.S. AND CANADA ON MONDAY...WHILE THE TROUGH ASSOCIATED WITH
IT TRACKS ACROSS THE NORTHERN AND CENTRAL PLAINS. IT APPEARS THAT
PRECIPITATION CHANCES WILL BE MINIMAL IN OUR AREA. SOME LIGHT
SHOWERS COULD LINGER IN FAR SOUTHEAST NEBRASKA PAST 6 AM...SO LEFT
A LOW POP THERE UNTIL ABOUT 9 AM. ON TUESDAY...FELT BETTER CHANCES
FOR SHOWERS WOULD STAY TO OUR NORTH OR NORTHEAST.
A RIDGE OF HIGH PRESSURE AT THE SURFACE WILL BUILD INTO THE AREA
MONDAY NIGHT INTO TUESDAY...SETTING THE STAGE FOR WHAT LOOKS LIKE A
COOL EARLY MORNING FOR WEDNESDAY. WENT SEVERAL DEGREES BELOW
GUIDANCE FOR LOWS TUESDAY NIGHT/WEDNESDAY MORNING WITH MAINLY CLEAR
SKIES AND LIGHT WINDS EXPECTED.
A MID TROPOSPHERIC RIDGE WILL BUILD ACROSS THE REGION WEDNESDAY
THROUGH THURSDAY WITH DRY CONDITIONS AND MILDER TEMPERATURES. MODELS
SHOW NEXT COLD FRONT APPROCHING THE AREA FROM THE NORTHWEST BY LATE
THURSDAY NIGHT. THEN HAVE LOW POPS FOR PARTS OF THE AREA INTO NEXT
WEEKEND.
MILLER
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
ZAPOTOCNY
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1125 PM EDT TUE MAY 8 2012
.SYNOPSIS...
A STRONG COLD FRONT WILL APPROACH FROM THE WEST TONIGHT AND BRING
SHOWERS AND THUNDERSTORMS TO THE AREA WEDNESDAY AND WEDNESDAY NIGHT.
COOL AND DRY HIGH PRESSURE WILL BUILD INTO THE AREA THURSDAY AND
PERSIST THROUGH THE WEEKEND. THE HIGH WILL SLIP OFF THE COAST BY
LATE SUNDAY MOVING FARTHER OFFSHORE AS NEXT FRONT APPROACHES LATE
MONDAY INTO TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1125 PM TUESDAY...TRENDS FROM THE LATEST KLTX AND SURROUNDING
88-DS INDICATE THE PCPN ACTIVITY REMAINS WEST THRU NORTHWEST OF THE
ILM CWA. THE ACTIVITY CONTINUES TO DISSIPATE AS IT APPROACHES THE
ILM CWA. HRRR/RUC MODELS INDICATE THE LACK OF INSTABILITY IE.
CAPE...AS THE MAJOR REASON FOR THE LACK OF PCPN DEVELOPMENT ACROSS
THE ILM CWA LATE THIS EVENING. HAVE TRIMMED POPS FOR THE REMAINDER
OF THE OVERNIGHT. LATEST HRRR INDICATES LOW CAPE VALUES TOWARD
DAYBREAK WEDNESDAY. HOWEVER MODELS INDICATE SUBSIDENCE ALOFT
DURING THE PRE-DAWN WED HOURS WHICH WILL LIMIT TSRA PRODUCTION AND
COVERAGE ACROSS THE ILM CWA. AS FOR POPS...WILL BASICALLY ADVERTISE
NO CHANCE FOR THE IMMEDIATE COAST AND LOW CHANCE MAINLY WEST OF I-95
...TOWARD DAYBREAK WED. HAVE LEANED WITH NAM MOS GUIDANCE FOR MIN
TEMPS TONIGHT...WITH SOME MINOR TWEAKS EITHER UPWARDS ALONG THE
IMMEDIATE COAST OR LOWER...LOW TO MID 60S...ACROSS AREAS OBSERVING
MOSTLY CLEAR SKIES. SSTS IN THE 70S COMBINED WITH ONSHORE FLOW WILL
LIKELY KEEP THE IMMEDIATE COASTAL COUNTY ZONES NEAR 70.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 245 PM TUESDAY...MAIN FORECAST CHALLENGE IS THE POTENTIAL FOR
SEVERE WEATHER WITH A COLD FRONT MOVING THROUGH THE AREA WEDNESDAY
AND WEDNESDAY NIGHT. AMPLE CLOUD COVER AHEAD OF THE FRONT WILL
IMPACT THE INSTABILITY...HOWEVER RRQ OF AN H3 JET WILL ADD LIFT TO
THE REGION RESULTING IN DECENT CONVECTIVE COVERAGE. IN THE END...MAY
NEED TO DEAL WITH A FEW SEVERE TSTMS WITH DAMAGING WINDS AS THE
PRIMARY THREAT. SPC CONTINUES TO HIGHLIGHT NEARLY THE ENTIRE ILM
FORECAST AREA IN A SLIGHT RISK.
ONCE THE FRONT MOVES THROUGH MUCH DRIER CONDITIONS WILL PREVAIL WITH
NEAR SEASONABLE TEMPERATURES ON TAP. PRECIPITABLE WATER VALUES OF
1.7 INCHES WEDNESDAY AFTERNOON/EVE WILL DROP BELOW 0.75 INCHES
THURSDAY. TIME HEIGHT CROSS SECTIONS INDICATE A VERY DRY COLUMN
ABOVE H8 WHICH WILL LEAD TO MOSTLY SUNNY SKIES BY THURSDAY MORNING.
HIGHS ON THURSDAY WILL BE AROUND 80 MOST LOCATIONS AND LOWS WILL BE
A COUPLE CATEGORIES BELOW NORMAL THURSDAY NIGHT (LOWER 50S PEE DEE
AND LBT AREAS TO THE MID 50S INLAND COASTAL AREAS). LASTLY...UNTIL
THE LOW-LEVEL WIND FIELD WEAKENS COULD SEE 20-25 MPH GUSTS IN
NORTHWEST FLOW THURSDAY MORNING.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 245 PM TUESDAY...PERIOD STARTS OFF DRY WITH TEMPERATURES NEAR
TO SLIGHTLY CLIMO AS 5H TROUGH AXIS MOVES OFF THE COAST AND SURFACE
HIGH SETTLES IN FROM THE NORTH. COMBINATION OF SURFACE HIGH AND WEAK
5H RIDGE AXIS OVER THE WEEKEND SHOULD KEEP THE AREA DRY FOR MUCH OF
THE WEEKEND. LATE SUN AFTERNOON RETURN FLOW AROUND EXITING HIGH AND
DEEPER SOUTHWEST FLOW ON THE WEST SIDE OF EXITING RIDGE ALOFT MAY
LEAD TO SOME CONVECTION ACROSS WESTERN AREAS. WILL CARRY SILENT POP
FOR SUN AFTERNOON AT THIS POINT. PRECIP CHANCES INCREASE DURING THE
MON/TUE TIMEFRAME. MEDIUM RANGE GUIDANCE IS SHOWING BROAD 5H TROUGH
DEVELOPING OVER THE EASTERN US NEXT WEEK...THOUGH MANY OF THE
PARTICULARS REMAIN IN QUESTION. IT DOES APPEAR THERE WILL BE PLENTY
OF MOISTURE IN THE AREA...GIVEN THE DEEP SOUTHWEST FLOW. SETUP MON
LOOK FAVORABLE AS FAR AS DIURNAL CONVECTION IS CONCERNED. TUE LOOKS
A LITTLE MORE SYNOPTIC WITH A WEAK COASTAL TROUGH OR WARM FRONT IN
THE VICINITY AND LOW PRESSURE MOVING UP THE COAST. AT THIS POINT
WILL CONTINUE WITH SLIGHT CHANCE MON/MON NIGHT INCREASING TO LOW
CHANCE FOR TUE/TUE NIGHT. TEMPERATURES WILL REMAIN NEAR TO SLIGHTLY
BELOW CLIMO THROUGH THE PERIOD.
&&
.AVIATION /00Z WEDNESDAY THROUGH SATURDAY/...
AS OF 00Z...PRECIPITATION LOOMING OFF TO THE WEST WITH CLOUD DECK
ALONG THE COAST ERODING AS SEA BREEZE FRONT MOVES INLAND AND STABLE
MARITIME AIR MASS MOVES ACROSS THE REGION. MODELS ARE IN PRETTY GOOD
AGREEMENT WITH HOLDING OFF ANY PRECIPITATION ACROSS THE TERMINALS
FOR THE OVERNIGHT PERIOD BEFORE BRINGING THE SHOWERS AND STORMS
AHEAD OF THE COLD FRONT ON WEDNESDAY AFTERNOON INTO THE EVENING. LOW
LEVEL MOISTURE WILL CONTINUE TO BE ON THE INCREASE TONIGHT ON SOUTH
WINDS COURTESY OF THE HIGH OFF THE COAST. WILL BE A BIT MORE
OPTIMISTIC FOR THE OVERNIGHT PERIOD AND KEEP TERMINALS VFR THROUGH
08Z-09Z ACROSS THE INLAND TERMINALS WHERE SOME PATCHY FOG IS
FORECAST TO DEVELOP. HAVE KEPT CATEGORICAL PRECIPITATION OUT OF THE
TERMINALS ON WEDNESDAY AND JUST WENT WITH VICINITY FORECAST THROUGH
20Z-21Z BEFORE GOING WITH TEMPO GROUP. CLIMO HAS SHOWN THAT THE
PROBABILITY OF SHOWERS OR THUNDERSTORMS TO BE OVER A PARTICULAR
TERMINAL DURING THE AFTERNOON TO BE RATHER LOW SO WILL FORECAST VFR
FOR THE TERMINALS THROUGH LATE AFTERNOON. LIKELIHOOD OF MVFR OR IFR
WILL INCREASE LATE IN THE AFTERNOON INLAND AND TOWARDS THE COAST
DURING THE EVENING WITH FROPA.
EXTENDED OUTLOOK...MODERATE CONFIDENCE FOR SCATTERED TO POSSIBLE
NUMEROUS SHOWERS AND THUNDERSTORMS WEDNESDAY AFTERNOON THROUGH
WEDNESDAY NIGHT...WITH INTERMITTENT IFR POSSIBLE. BECOMING VFR
THURSDAY AND CONTINUING THROUGH SUNDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1125 PM TUESDAY...SE-S WINDS TO START THE EVENING...AND WILL
SLIGHTLY VEER TO THE S-SSW OVERNIGHT. SPEEDS TO REMAIN AROUND 10 KT.
THE LOW SPEEDS CAN BE CONTRIBUTED TO A WEAK/RELAXED SFC PG...WHICH
WILL REMAIN ACROSS THE WATERS DURING THE REMAINING OVERNIGHT PERIOD.
SIGNIFICANT SEAS WILL RANGE BETWEEN 2 AND 4 FT...WITH THE 4 FOOTERS
PRIMARILY ACROSS THE WATERS FROM CAPE FEAR NORTHWARD. THE MAJOR
CONTRIBUTOR FOR THE SIG. SEAS AS ILLUSTRATED BY WAVEWATCH3 WILL COME
FROM A 3 TO 5 FT NE SWELL EXHIBITING 10-11 SECOND PERIODS JUST
OFFSHORE AND BEYOND THE SHOALS. FOR THE COASTAL WATERS...THE SWELL
DIRECTION WILL VEER TO THE ENE AND DROP TO 2 TO 3 FT DUE TO WAVE
REFRACTION ACROSS THE SHALLOW SHOALS OFF CAPE LOOKOUT AND OFF CAPE
FEAR. ADD THE 1 FT SHORT PERIOD LOCAL WIND WAVE...AND SIG SEAS EQUAL
TO 2 TO 4 FT.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 245 PM TUESDAY...SOUTHERLY WINDS WEDNESDAY AHEAD OF THE COLD
FRONT WILL VEER TO A WEST-NORTHWEST DIRECTION IN ITS WAKE WEDNESDAY
NIGHT. ADDITIONAL VEERING TO A NORTHERLY DIRECTION EXPECTED THURSDAY
AS HIGH PRESSURE BUILDS ACROSS THE WATERS. SPEEDS WILL INCREASE
10-15 KTS AHEAD OF THE FRONT THEN PEAK AROUND 15 KNOTS IN ITS WAKE.
COULD SEE A MINOR SURGE ARRIVE OVER THE WATERS LATE THURSDAY WITH
SPEEDS PICKING UP OVER THE WATERS AWAY FROM THE COAST. SEAS WILL
RANGE FROM 2-3 FT ACROSS LONG BAY AND 2-4 FT ACROSS ONSLOW BAY
WEDNESDAY...THEN NEARLY A SOLID 4 FT OFF CAPE FEAR AND 3 FT OVER
LONG BAY WED NIGHT. SEAS WILL BE AROUND 3 FT THURSDAY THEN SLIGHTLY
INCREASE AWAY FROM THE COAST LATE THURSDAY NIGHT WITH THE
AFOREMENTIONED MINOR SURGE. OTHERWISE...SCATTERED TO NUMEROUS
SHOWERS AND TSTMS WILL LOCALLY ENHANCE WINDS...ESPECIALLY WEDNESDAY
NIGHT.
LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 245 PM TUESDAY...NORTHERLY FLOW AT THE START OF THE PERIOD
WILL BE DECREASING AND VEER TO NORTHEAST THROUGHOUT THE DAY AS
SURFACE HIGH SETTLES SOUTH. RELAXED GRADIENT WILL SEE SPEEDS DROP TO
10 KT OR LESS BY AFTERNOON. WEAK SEA BREEZE DEVELOPS IN THE
AFTERNOON...BUT COOLER NORTHEAST FLOW WILL HELP LIMIT THE STRENGTH
OF THE NEAR SHORE CIRCULATION. LIGHT NORTHEAST FLOW CONTINUE TO VEER
FRI NIGHT INTO SAT AS CENTER OF THE HIGH MOVES OFF THE COAST JUST
NORTH OF THE WATERS. EAST TO SOUTHEAST FLOW AROUND 10 KT SAT BECOMES
SOUTHEAST SAT NIGHT AND SUN. SPEEDS START TO PICK UP SUN INTO SUN
NIGHT AS GRADIENT BECOMES A LITTLE MORE DEFINED. WINDS UNDER 15 KT
THROUGH THE PERIOD WILL KEEP SEAS 2 TO 3 FT.
&&
.TIDES/COASTAL FLOODING...
AS OF 1125 PM TUESDAY...HAVE EXTENDED THE ATLANTIC WATERFRONT MINOR
COASTAL FLOOD THREAT TO 1 AM WED. THIS A RESULT OF THE LATEST
OBSERVED TIDE READINGS CONTINUING WITHIN THRESHOLDS...EVENTHOUGH
THE OCCURRENCE OF HIGH TIDE HAS OCCURRED. THE ET SURGE MODEL
APPEARED TO DO QUITE WELL WITH TODAYS MIDDAY HIGH TIDE...THE LOWER
OF THE 2 PER DAY. WITH THAT SAID...THE ET MODEL STILL BRINGS EAST
FACING BEACHES AND CAPE FEAR RIVER TO THE VERY CUSP OF MINOR
FLOOD...WHICH IS TYPICALLY QUITE COMMON. SOME FLOODING THRESHOLDS
UNCERTAINTY FOR BRUNSWICK COUNTY BEACHES WITH THE TIDE GAGE NOT
WORKING...BUT THERE WERE SEVERAL REPORTS TODAY OF FLOODING AT OCEAN
ISLE BEACH. AS A RESULT...HAVE CONTINUED TO INCLUDE IN THE ADVISORY
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY FROM 8 PM THIS EVENING TO 1 AM EDT
TONIGHT FOR NCZ106-108-110.
COASTAL FLOOD ADVISORY FROM 11 PM THIS EVENING TO 3 AM EDT
WEDNESDAY FOR NCZ107.
MARINE...NONE.
&&
$$
NEAR TERM...DCH
SHORT TERM...SRP
LONG TERM...III
AVIATION...MAC
TIDES/COASTAL FLOODING...DCH/MBB
AREA FORECAST DISCUSSION
NWS RALEIGH NC
759 PM EDT TUE MAY 8 2012
.SYNOPSIS...
CONVECTIVE OUTFLOW WILL DRIFT EASTWARD ACROSS THE WESTERN PIEDMONT
THIS EVENING. MEANWHILE...A COLD FRONT WILL APPROACH FROM THE WEST
TONIGHT AND PROGRESS SLOWLY EASTWARD THROUGH CENTRAL NC WEDNESDAY
AFTERNOON AND EVENING. DRY HIGH PRESSURE WILL FOLLOW FOR THURSDAY
THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS OF 315 PM TUESDAY...
LATEST SFC ANALYSIS SHOWS A COLD FRONT EXTENDING SOUTHWESTERLY
ACROSS THE OH AND TN VALLEYS. MULTIPLE WEAK SFC TROUGHS WERE NOTED
ACROSS THE SOUTHERN APPALACHIANS AND GA/SC. LATEST SPC MESOANALYSIS
INDICATES A WEAKLY UNSTABLE AIRMASS ACROSS FAR WESTERN NC AND SC
WITH MLCAPE VALUES OF AROUND 250-500 J/KG IN A REGION OF ENHANCED
SFC DEW POINTS IN THE LOW/MID 60S. FURTHER EAST ACROSS THE PIEDMONT
AND COASTAL PLAIN THE AIR MASS IS MORE STABLE WITH LITTLE OR NO
SBCAPE/MLCAPE IN A REGION OF DEW POINTS IN THE MID 50S TO AROUND 60.
SCT SHOWERS CONTINUE TO MOVE NORTHEAST AT AROUND 20KTS. MUCH OF
CENTRAL NC UNDER A BKN CLOUD DECK WITH CIGS RANGING FROM 3-5KFT.
RECENT SIMULATIONS FROM THE WRF HIRESW AND HRRR SUGGEST THAT THE SCT
CONVECTION WILL PERSIST INTO THE EVENING HOURS AND CONTINUE TO SHIFT
EASTWARD. IN FACT SOME SIMULATION SUGGEST THAT THE CONVECTION ACROSS
THE FOOTHILLS WILL INTENSIFY A BIT AND GROW INTO A BROKEN LINE AND
MOVE ACROSS THE WESTERN PIEDMONT INTO THE EASTERN PIEDMONT BUT
LIKELY WEAKEN OR HOLD WEST OF THE COASTAL PLAIN. THREAT OF SEVERE
CONVECTION THIS AFTN/EVE IS LIMITED WITH A WEAKLY UNSTABLE AIRMASS
THIS AFTN CHARACTERIZED BY MLCAPE VALUES LESS THAN 500 J/KG...MODEST
0-6KM BULK SHEAR OF 15 KTS OR LESS AND WEAK MID LEVEL LAPSE RATES.
GIVEN AN INCREASE IN PW VALUES NOW APPROACHING 1.7 INCHES IN THE
SOUTHERN PIEDMONT...SOME LOCATIONS COULD SEE HEAVY RAIN THIS
EVENING. THREAT OF PRECIPITATION OVERNIGHT DECREASES SOMEWHAT WITH
LIMITED FORCING FOR ASCENT BUT WILL MAINTAIN AT LEAST A SLIGHT CHC
POP OVERNIGHT. GIVEN WIDESPREAD CLOUDINESS...A LIGHT SOUTHERLY WIND
TRANSPORTING SLIGHTLY HIGHER DEW POINTS INTO THE REGION...HAVE EDGED
TOWARD THE WARMER END OF THE GUIDANCE ENVELOPE WITH LOWS IN THE
62-66 RANGE. -BLAES
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 315 PM TUESDAY...
THE NORTHERN STREAM SHORTWAVE WILL DIVE INTO THE OH VALLEY TOWARD
DAYBREAK ON WED. BOTH THE NAM/GFS HAVE TRENDED A LITTLE SHARPER WITH
THIS FEATURE AS IT PIVOTS EAST AND BECOMES NEUTRAL OR EVEN BRIEFLY
NEGATIVELY TILTED WEDNESDAY NIGHT. THE BEST FORCING FOR ASCENT WITH
THE WAVE WILL REMAIN IN WV/VA NORTHWARD. THE POLAR JET STRENGTHENS
ACROSS PA/NY AND EXTEND SOUTHWEST TO THE OH VALLEY WED AFTERNOON BUT
WILL LIKELY ONLY PROVIDE LIMITED FORCING FOR ASCENT OVER NC. WHILE
THE BEST FORCING WILL REMAIN NORTH OF NC...SFC DEW POINTS RECOVER
INTO THE LOWER TO MID 60S WHICH MAY BE SUFFICIENT FOR PERHAPS A
MODERATELY UNSTABLE AIRMASS WITH MLCAPE VALUES CLIMBING TO AROUND
1000 J/KG IN THE COASTAL PLAIN WITH REDUCED MLCAPE VALUES IN THE
PIEDMONT GIVEN A SHALLOWER BOUNDARY LAYER. NAM/GFS FORECAST
SOUNDINGS BOTH DEPICT A MOIST ENVIRONMENT WITH THIN CAPE AND LIMITED
DRY AIR ALOFT. BULK SHEAR VALUES INCREASE DURING THE AFTERNOON AND
REACH THE 25-30KT RANGE IN THE EAST AND AROUND 35KTS ACROSS THE
WEST. WHILE THE SHEAR IS SUFFICIENT TO SUPPORT SOME
ORGANIZATION...THE MOIST PROFILES SUGGEST THE SEVERE WEATHER THREAT
MAY BE SOMEWHAT LIMITED. WITH A GENERALLY LINEAR WIND PROFILE AND
THE MEAN WIND PARALLEL TO THE APPROACHING COLD FRONT...THE
CONVECTION WILL LIKELY TAKE ON A MORE LINEAR ORIENTATION. ANY
DISCRETE STORM WILL HAVE AN INCREASED SEVERE WEATHER THREAT GIVEN
THE MARGINAL POTENTIAL FOR SUPERCELLS AND SEMI STRAIGHT HODOGRAPHS
WHICH SUGGEST POSSIBLE SPLITTING SUPERCELLS. PW VALUES CLIMB TO
AROUND 1.75 INCHES AND THE CONVECTION WILL LIKELY BECOME ORIENTED
PARALLEL TO THE THE NORTHEAST MOTION...SUGGESTING THAT STORMS WILL
HAVE THE POTENTIAL TO DUMP HEAVY RAIN OVER A GIVEN LOCATION FOR A
PROLONGED PERIOD OF TIME. GIVEN THIS...THE PRIMARY SEVERE THREAT ON
WEDNESDAY AND WEDNESDAY EVENING WILL BE FLOODING AND WET DOWNBURSTS.
WILL RAMP UP POPS INTO THE LIKELY RANGE ON WEDNESDAY AFTERNOON AND
EARLY EVENING AND THEN QUICKLY DIMINISH POPS FROM WEST TO EAST AFTER
MIDNIGHT. HIGH TEMPERATURES ON WEDNESDAY WILL RANGE IN THE MID 70S
WEST TO THE UPPER 70S TO AROUND 80 EAST. WILL KEEP LOWS ON WEDNESDAY
NIGHT TOWARD THE HIGHER END OF THE GUIDANCE RANGE GIVEN THE CLOUD
COVER AND TENDENCY FOR OVERNIGHT LOWS TO REMAIN ELEVATED WITH COLD
FRONTAL PASSAGES LATE AT NIGHT. LOWS IN THE MID 50S NORTHWEST TO
AROUND 60 SOUTHEAST. -BLAES
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 300 PM TUESDAY...
THURSDAY THROUGH FRIDAY...THE UPPER TROUGH AXIS PUSHES EAST OF
CENTRAL NORTH CAROLINA QUICKLY DURING THE MORNING...WITH THE JET
ALOFT ALSO MOVING EAST. GOOD SUBSIDENCE TAKES PLACE AS HIGH PRESSURE
BUILDS IN...WITH BUFR SOUNDINGS AT 12Z STABLE TO DEEP CONVECTION
THROUGHOUT CENTRAL NORTH CAROLINA ON BOTH THE NAM AND THE GFS.
PRECIPITABLE WATER VALUES THAT FALL TO AROUND 0.75 INCH AROUND 12Z
THURSDAY FALL FURTHER TO AROUND 0.5 INCH BY 18Z THURSDAY...WHERE
THEY REMAIN THROUGH THE DAY ON FRIDAY. EXCEPT FOR VERY EARLY
THURSDAY...K INDICES ARE NEGATIVE...WELL NEGATIVE FOR FRIDAY.
WHILE IT WILL BE CLOSE TO THE INTERSTATE 95 CORRIDOR...EXPECT
PRECIPITATION TO BE JUST EAST OF CENTRAL NORTH CAROLINA BY 12Z
THURSDAY. FROM THERE...SKIES SHOULD CLEAR...BUT A RELATIVE MAXIMUM
OF 850MB THETA-E IN THE COASTAL PLAIN COULD YIELD SOME SHALLOW
AFTERNOON CU. IN ADDITION...A FEW CLOUDS COULD DRIFT FROM THE
MOUNTAINS...WHERE COOL AIR ALOFT WILL MAKE CONDITIONS THERE
RELATIVELY UNSTABLE...TOWARD THE TRIAD...BUT THE AIR SHOULD BE SO
STABLE THAT ONLY FEW SHOULD MAKE IT TO NEAR KINT AND KGSO. THE
SURFACE GRADIENT BEHIND THE FRONT WILL BE TIGHT TO START THE DAY...
RESULTING IN WIND GUSTS WITH MIXING AS HIGH AS THE LOWER 20S MPH
BEFORE 925MB WINDS FALL TO AROUND 15KT IN THE AFTERNOON...LESSENING
THE WIND GUSTS. UNDER OVERALL 850MB THETA-E TROUGHINESS FRIDAY...AND
AMPLE SUBSIDENCE AND DRY AIR...UNDER A SLACK GRADIENT AS WELL...
EXPECT PLENTY OF SUNSHINE AND CALM CONDITIONS FOR THE DAY...POSSIBLY
A BRIEF NOTICEABLE WIND GUST TO AROUND 10KT WITH MIXING EARLY.
BASED ON A COMBINATION OF 1000-850MB THICKNESSES...MOS GUIDANCE...
AND EXPECTED MIXING BASED ON BUFR SOUNDINGS...FORECAST HIGHS NEAR
THE HIGHER MAV MOS ON THURSDAY. WITH A FORECAST NEARER THE COOLER
GUIDANCE THURSDAY NIGHT UNDER A CLEAR SKY AND DIMINISHING WIND...
TEMPERATURES IN CENTRAL NORTH CAROLINA FRIDAY SHOULD BE SIMILAR TO
THURSDAY WITH A THICKNESS DIFFERENCE OF ONLY ABOUT 5M. FOR
NOW...WENT ABOUT A DEGREE COOLER FRIDAY COMPARED TO THURSDAY DUE TO
THE LIGHT...GENERALLY NORTHERLY LOW-LEVEL FLOW.
HEIGHTS ALOFT RISE NOTICEABLY FRIDAY NIGHT INTO SATURDAY...BEFORE
HEIGHTS START TO FALL AGAIN AS A WEAKENING UPPER-LEVEL LOW THAT
MOVES FROM THE SOUTHWEST STATES INTO THE SOUTH PLAINS SLOWLY PUSHES
FARTHER EAST. THE SOUTHEAST CONUS FALLS ON THE DOWNSTREAM SIDE OF
THE UPPER REMNANT TROUGH BY THE END OF THE WEEKEND...AND WHILE A
MID-LEVEL SHORTWAVE OF SOME STRENGTH SHOULD REACH CENTRAL NORTH
CAROLINA BY LATE SUNDAY...THE UPPER FLOW IS INITIALLY CONFLUENT AND
THE SURFACE RIDGE AXIS REMAINS OVERHEAD. DRY CONDITIONS SHOULD EXIST
FRIDAY NIGHT THROUGH SATURDAY IN HIGH PRESSURE SURFACE AND
ALOFT...AND WILL CONTINUE A DRY FORECAST FOR NOW THROUGH SUNDAY DUE
TO THE PRESENCE OF SURFACE HIGH PRESSURE AND THE CONFLUENT FLOW
ALOFT. LATE SUNDAY AND SUNDAY NIGHT...IT IS POSSIBLE THAT THE
SURFACE RIDGE AXIS STARTS TO MOVE NORTH OF THE AREA RESULTING IN
INCREASING ATLANTIC MOISTURE...AND WHILE AN ISOLATED SHOWER OR
THUNDERSTORM IS POSSIBLE...WILL LEAVE IT OUT OF THE FORECAST FOR NOW
THAT FAR OUT IN TIME. MOST OF THE GUIDANCE IS DRY OR TRENDING DRIER
FOR SUNDAY.
WHILE THE EVOLUTION OF SURFACE AND UPPER-LEVEL FEATURES ARE IN
QUESTION EARLY NEXT WEEK...CURRENTLY THE PREPONDERANCE OF THE
EVIDENCE SUGGESTS A MOISTENING AIR MASS WITH INCREASING LIFT. AT A
MINIMUM...ATLANTIC MOISTURE SHOULD BE ABLE TO SPREAD INTO CENTRAL
NORTH CAROLINA...AND THE UPPER-LEVEL FLOW...PERSISTENTLY
SOUTHWEST...BECOMES LESS CONFLUENT. AT LEAST SLIGHT CHANCES FOR
SHOWERS AND THUNDERSTORMS WILL BE FORECAST MONDAY...WITH SLIGHTLY
HIGHER CHANCES IN THAT CATEGORY OVER THE WESTERN PIEDMONT DUE TO
GREATER INSTABILITY AND CONVERGENCE EXPECTED TOWARD THE MOUNTAINS...
ALONG WITH A MORE FAVORABLE UPSLOPE FLOW FOR DEEPER CONVECTION WHICH
MAY THEN MOVE INTO THE TRIAD AND AREAS NEAR THE YADKIN RIVER ON THE
WESTERLY THERMAL WIND AS CURRENTLY FORECAST. BY TUESDAY...MOISTENING
CONTINUES...AND WITH A SLIGHTLY MORE DIFFLUENT FLOW ALOFT UNDER A
SERIES OF MID-LEVEL WAVES MOVING THROUGH ON THE SOUTHWEST FLOW...
AT LEAST CHANCES FOR SHOWERS AND THUNDERSTORMS ARE EXPECTED. GFSX
MOS ENSEMBLE GUIDANCE POPS ARE VIRTUALLY ALL ABOVE CLIMATOLOGY
MONDAY AND TUESDAY...AND IT IS POSSIBLE OVER TIME THAT CHANCES FOR
PRECIPITATION WILL INCREASE DURING PART OR ALL OF THOSE TWO DAYS...
WITH THAT INCREASE SEEMINGLY MORE LIKELY FOR TUESDAY.
1000-850MB THICKNESSES SUPPORT TEMPERATURES EACH DAY FROM THE MID
70S TO NEAR 80 DEGREES...BASICALLY AROUND NORMAL. HIGHEST
THICKNESSES ARE SATURDAY...BUT THE DAY TO DAY VARIATION IS ON THE
ORDER OF 5 TO 10M ON BOTH THE GFS AND ECMWF. LEANED TOWARD COOLER
VALUES TUESDAY DUE TO THE INCREASING POTENTIAL FOR CLOUDS AND
PRECIPITATION...BUT STILL SLIGHTLY ABOVE THE HPC GUIDANCE VALUES FOR
NOW BASED ON EXPECTED WARMER OVERNIGHT LOWS AS A RESULT OF CLOUD
COVER...AND SOME WARMING POTENTIAL ANTICIPATED DUE TO THE TIME OF
YEAR.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AS OF 755 PM TUESDAY...
A CLUSTER OF SHOWERS AND THUNDERSTORMS AND ASSOCIATED MVFR CEILINGS
AND MVFR-IFR VISIBILITY RESTRICTIONS WILL MOVE EASTWARD AND AFFECT
KINT/KGSO THROUGH AROUND 02Z. ADDITIONAL...MORE WIDELY-SCATTERED
SHOWERS AND STORMS WEST OF THE INITIAL LINE WILL LIKELY AFFECT AT
LEAST THE TRIAD TERMINAL VICINITIES THROUGH MIDNIGHT. WHILE THE
SHOWERS AND STORMS WILL WEAKEN WITH THE LOSS OF DAYTIME HEATING/
DESTABILIZATION...SOME OF THEM MAY HOLD TOGETHER AND AFFECT THE
VICINITY OF KRDU AFTER 04Z. VFR CONDITIONS ARE EXPECTED TO CONTINUE
DOWNSTREAM AT KFAY AND KRWI WELL INTO THE NIGHT...UNTIL BOUNDARY
LAYER COOLING PROMOTES THE DEVELOPMENT OF MVFR VISIBILITY
RESTRICTIONS BETWEEN 08-12Z. OTHERWISE...MOIST SOUTHERLY FLOW WILL
LIKELY RESULT IN THE DEVELOPMENT OF IFR-MVFR STRATUS FROM WEST TO
EAST LATE TONIGHT THROUGH EARLY WED; AND THIS STRATUS WILL SLOWLY
LIFT THROUGH MVFR RANGE THROUGH EARLY WED AFTERNOON. THE LIFTING OF
THE STRATUS...AND POSSIBLE SCATTERING AT EASTERN TERMINALS FROM KRWI
TO KFAY...WILL PROVIDE FOR WEAK DESTABILIZATION AND RESULTANT
NUMEROUS TO WIDESPREAD SHOWER AND THUNDERSTORM DEVELOPMENT ALONG AND
AHEAD OF A COLD FRONT THAT WILL SETTLE SLOWLY EASTWARD THROUGH
CENTRAL NC LATE WED AFTERNOON AND EVENING.
OUTLOOK: THE PASSAGE OF THE COLD FRONT AND ARRIVAL OF DRY HIGH
PRESSURE FROM THE WEST WILL RESULT IN CLEARING SKIES AND VFR
CONDITIONS FROM WEST TO EAST BETWEEN 23Z AT TRIAD TERMINALS AND 05Z
AT EASTERN TERMINALS. VFR HIGH PRESSURE WILL THEN DOMINATE THROUGH
THE WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MWS
NEAR TERM...BLAES
SHORT TERM...BLAES
LONG TERM...DJF
AVIATION...MWS
AREA FORECAST DISCUSSION
NWS TULSA OK
1141 PM CDT SUN MAY 6 2012
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
VFR CONDITIONS ARE OCCURRING IN ADVANCE OF A COLD FRONT
THAT IS POISED TO MOVE INTO NORTHEAST OKLAHOMA. SHOWERS
AND THUNDERSTORMS CURRENTLY ALONG AND NEAR THE COLD FRONT
WILL MOVE INTO THE AREA OVERNIGHT AFFECTING THE NORTHEAST
OKLAHOMA AND NORTHWEST ARKANSAS TAF SITES OVERNIGHT INTO
EARLY MONDAY MORNING. MVFR TO IFR CONDITIONS WILL BE POSSIBLE
WITH THE THUNDERSTORMS. MVFR CEILINGS WILL MOVE INTO THE
REGION IN THE WAKE OF THE COLD FRONT. VFR CONDITIONS ARE EXPECTED
TO RETURN MONDAY AFTERNOON/EVENING.
&&
.PREV DISCUSSION... /ISSUED 921 PM CDT SUN MAY 6 2012/
..UPDATE...
DISCUSSION...
COLD FRONT CURRENTLY EXTENDING FROM EAST CENTRAL KANSAS SOUTHWARD
INTO SOUTHWEST OKLAHOMA HAS PROGRESSED ONLY SLOWLY EASTWARD THIS
EVENING...AND HAS RECENTLY BECOME THE FOCUS FOR EXPANDING
THUNDERSTORM COVERAGE ACROSS EASTERN KANSAS. 00Z KOUN SOUNDING
SAMPLED THE HIGHLY UNSTABLE YET CAPPED AIRMASS CURRENTLY IN PLACE.
GIVEN THE ABSENCE OF LARGE SCALE FORCING IN PLACE...THE FOCUS FOR
LIFT WILL REMAIN NEAR THE COLD FRONT. THE EVOLUTION OF CONVECTION
ALONG THE FRONT IS UNCLEAR AS SOME SHORT TERM MODEL SOLUTIONS
DEVELOP AN AGGRESSIVE COLD POOL WHICH SPREAD SOUTHEASTWARD DURING
THE EARLY MORNING HOURS. THE 00Z NAM IS IN THIS CAMP HOWEVER WE
QUESTION WHETHER IT IS RELEASING THE HIGH CAPE ENVIRONMENT TOO
EASILY...WITH LOCAL WRF RUNS MUCH LESS AGGRESSIVE IN SOUTHEASTWARD
DEVELOPMENT. THE HRRR SOLUTIONS HAVE BEEN SOMEWHAT CONSISTENT AND
OFFER A COMPROMISE WHICH SEEMS REASONABLE AT THIS POINT...AND
ALLOW CONVECTION TO SPREAD SOUTHEASTWARD OFF THE FRONT BUT
EVENTUALLY LIMIT THE SOUTHWARD ADVANCE DURING THE OVERNIGHT HOURS.
THUS THE UPDATED FORECAST WILL TRIP POPS ACROSS THE SOUTHERN HALF
OF THE FORECAST AREA AND RETAIN THE FOCUS FOR NORTHEAST OKLAHOMA
INTO FAR NORTHWEST ARKANSAS. THE STABILIZING BOUNDARY LAYER LOOKS
TO KEEP THE HIGHEST INSTABILITY FROM BEING REALIZED...HOWEVER
POOLING DEEPER MOISTURE NEAR THE FRONTAL ZONE WILL RETAIN
SUFFICIENT ELEVATED INSTABILITY TO WARRANT A SEVERE WEATHER RISK
OVERNIGHT. OVERNIGHT LOW TEMPS LOOK ON TRACK ASSUMING SOME TYPE OF
OUTFLOW COOLS LOCATIONS AHEAD OF THE FRONTAL POSITION BEFORE
SUNRISE.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...10
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
354 PM CDT MON MAY 7 2012
.DISCUSSION...
ISOLATED THUNDERSTORMS THAT DEVELOPED ALONG THE BAY BREEZE THIS
AFTERNOON CONTINUE TO MOVE TO THE SOUTHWEST ACROSS BRAZORIA COUNTY
AND SHOULD MOVE OFFSHORE WITHIN THE NEXT COUPLE OF HOURS PER
LATEST HRRR RUNS. ADDITIONAL DEVELOPMENT INLAND IS POSSIBLE AS THE
OUTFLOW BOUNDARY FROM THIS ACTIVITY CONTINUES TO PUSH WESTWARD
ACROSS HARRIS COUNTY.
TO OUR WEST...THUNDERSTORMS CONTINUE TO INCREASE IN COVERAGE
ACROSS THE NORTHERN HILL COUNTRY ALONG AND AHEAD OF A COLD FRONT
MOVING SOUTHWARD THROUGH THE STATE. THIS ACTIVITY HAS SPREAD
EASTWARD OVER THE PAST FEW HOURS TO NEAR THE I-35 CORRIDOR AND
SHOULD CONTINUE TO DEVELOP EASTWARD OVER THE NEXT FEW HOURS. THIS
ACTIVITY WILL LIKELY MOVE INTO OUR CWA LATE THIS EVENING ALTHOUGH
SOME DEVELOPMENT ACROSS OUR NORTHERN COUNTIES THIS AFTERNOON IS
POSSIBLE AS THE AREA REMAINS GENERALLY UNCAPPED WITH TEMPERATURES
IN THE UPPER 80S AND LOW 90S. MODEL SOUNDINGS SUGGEST CAPE VALUES
OF 2500-3000 WITH LI VALUES BETWEEN -6 AND -9 ACROSS THE NORTHERN
HALF OF OUR REGION SO ANYTHING THAT DOES DEVELOP THIS AFTERNOON OR
EVENING HAS THE POTENTIAL TO BE SEVERE WITH DAMAGING WINDS AND
LARGE HAIL.
EXTENDED FORECAST REMAINS RELATIVELY UNCHANGED. PRECIPITATION WILL
CONTINUE TO INCREASE ACROSS THE REGION ON TUESDAY AS THE FRONTAL
BOUNDARY SAGS SOUTHWARD INTO THE REGION. THURSDAY LOOKS TO BE OUR
DRIEST DAY OF THE WEEK BEFORE A STRONG UPPER LEVEL LOW MOVES INTO
THE STATE. GOOD DIVERGENCE ALOFT AHEAD OF THIS SYSTEM SHOULD ALLOW
FOR FAIRLY WIDESPREAD PRECIPITATION FROM LATE THURSDAY NIGHT INTO
FRIDAY ACROSS OUR REGION. GFS CONTINUES TO BE MORE PROGRESSIVE
WITH MOVING THIS SYSTEM EAST OF THE AREA WHILE THE ECMWF CONTINUES
TO HOLD THE TROUGH AXIS WEST OF OUR AREA ON FRIDAY...MUCH THE SAME
AS ITS 00Z RUN. GIVEN THIS POSSIBILITY WILL GO AHEAD AND KEEP SOME
POPS LINGERING ACROSS THE REGION FOR SATURDAY. 38
&&
.MARINE...
LIGHT TO MODERATE ONSHORE WINDS WILL PERSIST UNTIL A COLD FRONT
MOVES SOUTHWARD AND STALLS NEAR THE COAST ON TUESDAY. MODERATE TO
POSSIBLY STRONG EAST TO NORTHEAST WINDS AND ELEVATED SEAS ARE
EXPECTED TO DEVELOP THURSDAY THROUGH SATURDAY WITH CAUTION OR
ADVISORY FLAGS ANTICIPATED. 42
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 71 83 64 80 59 / 50 60 50 20 20
HOUSTON (IAH) 72 85 68 81 62 / 20 30 50 30 20
GALVESTON (GLS) 73 83 74 81 69 / 10 20 40 40 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...38
AVIATION/MARINE...42
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1155 PM CDT SUN MAY 6 2012
.AVIATION...
MAIN AVIATION CONCERN IS STILL THE EXPECTED SPREAD AND DEVELOPMENT
OF LOW STRATUS ACROSS THE REGION EARLY MONDAY MORNING. LATEST GUIDANCE
IS SLIGHTLY MORE PESSIMISTIC AND WE HAVE ADJUSTED THE TAFS TO SHOW
A LONGER DURATION OF MVFR CEILINGS. A PERIOD OF IFR CEILINGS AND
PERHAPS EVEN SOME LIGHT -DZ ARE POSSIBLE AS WELL. CEILINGS MAY
STILL LIFT TO VFR BY MIDDAY BUT CONFIDENCE HAS DECREASED. SHRA AND
TSRA CHANCES ARE POSSIBLE AT KLBB AT THE VERY END OF THE TAF PERIOD.
&&
.PREV DISCUSSION... /ISSUED 629 PM CDT SUN MAY 6 2012/
AVIATION...
VFR CONDITIONS EXPECTED TO CONTINUE UNTIL 07Z-08Z...AFTER WHICH
LOW STRATUS IS FORECAST TO EXPAND SOUTH FROM THE PANHANDLES AND
AFFECT KLBB AND KCDS WITH MVFR CEILINGS...AND POSSIBLY A PERIOD OF
IFR CEILINGS AT KLBB EARLY MONDAY MORNING. THE CEILINGS SHOULD
SLOWLY LIFT AT BOTH TERMINALS ABOVE MVFR BY LATE MORNING OR MIDDAY
MONDAY...WITH WX CONDITIONS THEN EXPECTED TO DETERIORATE MONDAY
NIGHT AFTER 0Z. NE SFC WINDS BETWEEN 10 TO 18 KTS WILL PREVAIL.
PREV DISCUSSION... /ISSUED 444 PM CDT SUN MAY 6 2012/
UPDATE...
QUICK UPDATE TO ADD AN ISOLATED THUNDERSTORM MENTION FOR THE NEXT
COUPLE OF HOURS ACROSS THE EXTREME SOUTHEAST ZONES...WHERE HIGH-
BASED STORMS WERE DEVELOPING. NO OTHER CHANGES MADE TO THE
FORECAST ATTM.
PREV DISCUSSION... /ISSUED 257 PM CDT SUN MAY 6 2012/
SHORT TERM...
COLD FRONT HAS SLOWED THIS AFTN AND AS OF 19Z EXTENDED ALONG A LINE
FROM SEMINOLE-POST-PADUCAH NORTHWEST OF A DRYLINE FROM NEAR LAKE ALAN
HENRY TO GUTHRIE. ENHANCED CONVERGENCE WHERE THESE TWO BOUNDARIES
MEET IS EVIDENT ON LAPS DATA...HOWEVER A LACK OF CU THUS FAR
CONFIRMS CAPPING IS STILL QUITE ROBUST. HRRR SEEMS AWFUL BULLISH IN
CONVECTING NEAR KING AND STONEWALL COUNTIES BY 20Z. TEND TO BELIEVE
IF STORMS MATERIALIZE THEY WILL BE DELAYED IN TIME AND DISPLACED
FARTHER EAST...SO POPS WERE LEFT SILENT FOR NOW.
TONIGHT...THE AXIS OF A SURFACE HIGH WILL SHARPEN SSW INTO ERN NM
ALLOWING WINDS AROUND 850MB TO VEER NELY AND BEGIN TAPPING A RICHER
FIELD OF MOISTURE PRESENTLY IN NWRN OK. LOW CLOUDS ALREADY IN THE
CENTRAL TX PANHANDLE SHOULD EXPAND SOUTH TONIGHT IN RESPONSE TO THIS
PROCESS.
MONDAY...INITIAL COOL SURFACE RIDGING IS FORECAST TO WEAKEN IN
RESPONSE TO INCREASING WARM ADVECTION AND PRESSURE FALLS FROM SRN NM
INTO THE PERMIAN BASIN. DRIVING FORCE BEHIND THIS IS TIED TO AN
APPROACHING UPPER TROUGH CURRENTLY NEAR BAJA CA AND AN ASSOCIATED
TROPOPAUSE JET STREAK DOWNSTREAM. BRUNT OF THIS FORCING WILL NOT
AFFECT OUR CWA UNTIL THE FOLLOWING PERIOD...HOWEVER SUSTAINED LIGHT
ELY UPSLOPE FLOW THROUGHOUT THE LOWEST 5K FEET COMBINED WITH AN
ELEVATED BUT SHARPENING BAROCLINIC ZONE APPEAR SUFFICIENT FOR
CONVECTION IN ERN NM BY MIDDAY. FORECAST SOUNDINGS HERE BY LATE AFTN
INDICATE SBCAPE AND ELEVATED CAPE OF 500-1000 J/KG EMBEDDED WITHIN
STRONG 0-6KM BULK SHEAR OF 50-60 KNOTS. CURRENT THINKING IS STORMS
IN NM COULD THREATEN THE WRN SOUTH PLAINS BY LATE AFTN WITH A
CONDITIONAL THREAT OF SOME BEING SEVERE. DID REMOVE POP MENTION OFF
THE CAPROCK TOMORROW AS LIFT HERE APPEARS MUCH TOO SHALLOW TO
OVERCOME A STOUT EML AROUND 750MB. WITH STRATUS EXPECTED TO LINGER
MUCH OF THE DAY...TEMPS AREA WIDE WILL FALL BELOW NORMAL FOR THE
FIRST TIME SINCE MID APRIL!
LONG TERM...
THE CLOSED LOW PROGGED TO BE PINCHED OFF FROM THE UL TROF EDGING
ACROSS THE ROCKIES WILL DIVE SOUTH OUT OF UT INTO NRN MEXICO THRU
WED EVENING. FROM THERE GUIDANCE HAS COME TO BETTER AGREEMENT WITH
THE TRACK OF THE LOW AS IT PUSHES EASTWARD INTO WTX...ALBEIT A SLOW
PROGRESSION. THIS COMBINED WITH A QUASI-STATIONARY FRONT TO THE
SOUTH...POSSIBLE AS FAR SOUTH AS THE RGV...WILL CONTRIBUTE TO
CONTINUED PRECIP CHANCES EACH DAY DURING THE WEEK.
THE FIRST AND BEST PRECIP CHANCE REMAINS ON TUE AS A SECONDARY 850
FRONT PUSHES THRU THE AREA AS THE SFC RIDGE BUILDS IN OVER THE
PANHANDLE. NAM/GFS AGREE UPON SOME 305K ISENTROPIC UPGLIDE AOA 12Z
TUE. THIS COMBINED WITH THE CONTINUED UL DIVERGENT REGION OVER THE
REGION TUE...THE BEST CHANCES FOR HEAVY PRECIP LOOKS TO REMAIN IN
THE MORNING HOURS...WITH CHANCES TRENDING DOWN FROM THERE AS THE SFC
RIDGE SETTLES IN TO THE NORTH. THIS EVENT CONTINUES TO LOOK LIKE A
DESCENT RAIN MAKER...WITH ONLY LIMIT INSTABILITY /GENERALLY UNDER
200 J/KG MUCAPE/. THEREFORE...HAVE ONCE AGAIN LOWER THUNDER TO ONLY
AN ISOLATED MENTION.
WED 00Z ON...THE BEST PRECIP CHANCES WILL BE TIED TO THE FRONT TO
THE SOUTH AND THE AFOREMENTIONED UL LOW EDGING EAST.
THEREFORE...MOST OF THE LATER HALF OF THE WEEK HAVE CONTINUED SLGT
CHANCE POPS MAINLY ACROSS THE SWRN ZONES. HOWEVER...BY THE WEEKEND
THERE REMAINS SOME SLIGHT DIFFERENCE ON SPEED AND TRACK OF THE UL
LOW OVER THE REGION AS WELL AS THE ONE OFF THE ERN CONUS.
THEREFORE...WILL CONTINUE ECMWF TREND FROM PREVIOUS THINKING.
MEADOWS
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 49 64 44 58 44 / 10 30 50 50 20
TULIA 52 66 48 60 45 / 10 20 40 40 20
PLAINVIEW 52 68 49 59 47 / 10 20 40 40 20
LEVELLAND 53 74 52 60 50 / 10 20 60 60 20
LUBBOCK 54 74 53 60 48 / 10 10 50 60 20
DENVER CITY 52 78 52 64 50 / 10 30 70 70 20
BROWNFIELD 52 76 52 60 50 / 10 20 60 70 20
CHILDRESS 59 75 54 70 50 / 10 10 30 40 20
SPUR 57 76 54 64 49 / 10 10 40 40 20
ASPERMONT 60 80 56 70 50 / 10 10 40 40 20
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
33
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
1147 PM CDT SUN MAY 6 2012
.DISCUSSION...SEE AVIATION SECTION BELOW.
&&
.AVIATION...VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH MUCH OF
TONIGHT WITH MVFR TOWARD MON MORNING AND BRIEF PERIODS OF IFR
CONDITIONS FROM ALI TO VCT DUE TO CIGS AND PATCHY FOG. VFR
CONDITIONS ARE EXPECTED TO RESUME BY MID TO LATE MON MORNING AND
CONTINUE THROUGH THE REMAINDER OF MON AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 712 PM CDT SUN MAY 6 2012/
DISCUSSION...SEE 00Z AVIATION DISCUSSION.
AVIATION...CONVECTION IS FIRING UP IN SOUTH CENTRAL TX...AND SOME
MODELS (TTU AND HRRR) BRING THIS CONVECTION INTO KVCT AREA.
CONFIDENCE IN THIS HAPPENING ARE NOT HIGH ENOUGH AT THIS TIME
(GIVEN WEAKER LOW LEVEL WINDS TONIGHT...INCREASING CIN/LOWER CAPES AND
LACK OF UPPER SUPPORT). THAT BEING SAID...EXPECTING MUCH LESS MID
AND HIGH CLOUD COVER TONIGHT...SO WILL BRING IN THE MVFR
CONDITIONS A BIT EARLIER...OVER KVCT AOA 03Z AND KCRP/KALI AOA
06Z. EXPECTING VFR AT KLRD (AND HAVE REMOVED THUNDER). HAVE ALSO
INCLUDED A BIT OF BR (ACTUALLY KEPT FROM PREVIOUS TAFS)...WITH
POSSIBLE IFR CIGS AT KALI. WILL HAVE MVFR CONDITIONS EAST OF KLRD
TIL ABOUT 17Z. AM EXPECTING LESS WIND TOMORROW AS WELL (WITH FRONT
TO THE NORTH)...BUT WINDS WILL BE A BIT GUSTY AT TIMES DURING THE
AFTERNOON SO HAVE A MENTION OF GUSTS (LESS THAN 25 KNOTS) FOR THE
AFTERNOON.
PREV DISCUSSION... /ISSUED 327 PM CDT SUN MAY 6 2012/
SHORT TERM (TONIGHT THROUGH MONDAY NIGHT)...MAIN FORECAST
CHALLENGE IN SHORT TERM PERIOD IS CONVECTIVE CHANCES TONIGHT AND
AGAIN MON NIGHT. SEVERAL BOUNDARIES WERE EMITTED LAST NIGHT FROM
MCS THAT REMAINED JUST TO OUR NORTH. ONE BOUNDARY HAS RECENTLY PUSHED
OFF THE LOWER TX COAST WHILE ANOTHER LOST ITS CHARACTERISTICS OVER
CRP CWA. SEA BREEZE IS TRYING TO PUSH INLAND BUT MAY NOT BE ABLE
TO COMPENSATE FOR SLIGHT CIN VALUES ACROSS COASTAL PLAINS...THUS
ISO CONVECTION MAY BE VERY LIMITED ACROSS THE EAST REMAINDER OF
THIS AFTERNOON. FOCUS FOR LATE AFTERNOON AND THIS EVENING TURNS TO
WESTERN ZONES WHERE CONVECTION MAY DEVELOP OR MOVE IN FROM OLD
MEX. SURFACE DRYLINE/TROUGH CURRENTLY EXTENDS FROM ACROSS EDWARDS
PLATEAU AND FARTHER SOUTH INTO MEX. CONVECTION IS ALREADY
DEVELOPING ALONG BOUNDARY AND IN HIGHER ELEVATIONS IN MEX AND SOME
OF THIS CONVECTION MAY APPROACH WESTERN ZONES THIS EVENING.
SEVERAL CONSECUTIVE RUNS OF HRRR WANT TO BRING CONVECTION THROUGH
WESTERN ZONES OVERNIGHT WHILE OTHER 4KM WRF RUNS WERE DRIER. DO NOT
WANT TO COMPLETELY DISCOUNT HRRR AS OTHER RUNS DID NOT HANDLE THIS
MORNING/S MCS AND RESULTANT MCV WELL AND THUS HAVE DECIDED TO GO
WITH LOW CHANCE POPS TONIGHT OUT WEST. ANY STORMS THAT OCCUR MAY
BECOME STRONG WITH AN ISOLATED SEVERE THREAT POSSIBLE. WILL ALSO
NEED TO WATCH FOR POTENTIAL CONVECTION ACROSS EWX CWA AS CORFIDI
VECTORS INDICATE POTENTIAL MOVEMENT INTO OUR NORTHERN ZONES. IF
CONVECTION DOES AFFECT CWA THERE IS A SLIGHT CHANCE IT MAY REACH
THE COASTAL PLAINS LATE TONIGHT BUT THOSE CHANCES ARE CURRENTLY
LOW AS CIN VALUES FARTHER EAST WILL BE INCREASING OVERNIGHT. FOR
MONDAY...MID LEVEL RIDGING SHOULD HELP KEEP S TX HOT WITH HIGHS
AROUND 100 ACROSS WESTERN ZONES AND 90S ACROSS THE EAST UNDER
PARTLY TO MOSTLY SUNNY SKIES IN THE AFTERNOON. GFS AND CMC WANT TO
DEVELOP CONVECTION TO OUR NW IN EWX CWA MON AFTERNOON WITH
CONVECTION MOVING SOUTHEAST TOWARDS OUR AREA DURING THE EVENING.
NAM AND ECMWF ARE LESS ROBUST AND KEEP MOST ACTIVITY TO OUR NORTH.
FOR NOW...GIVEN BETTER UPPER LEVEL DYNAMICS PROG TO EXIST...HAVE
GONE WITH CHANCE POPS ACROSS NW AREAS.
LONG TERM (TUESDAY THROUGH SUNDAY)...MAIN ISSUES FOR THE
EXTENDED PART OF THE FORECAST WILL BE CONVECTION THROUGHOUT THE
WEEK. PERIOD WILL START OF WILL UPPER LEVEL RIDGE MOVING EAST AND
DAMPENING AS UPPER LEVEL LOW DEEPENS OVER SOUTHERN CA/AZ. COLD
FRONT WILL BE MOVING SOUTHWARD ACROSS TEXAS DURING THE DAY ON
TUESDAY. MODELS PROG LEFT EXIT REGION OF UPPER JET TO BE
APPROACHING THE AREA AS WELL DURING THIS TIME. MOISTURE WILL BE IN
PLACE AS PWATS CLIMB TO ABOUT 1.4 TO 1.5 INCHES OVER SOUTH TEXAS.
THIS WILL LEAD TO SHOWERS AND STORMS DEVELOPING ALONG THE BOUNDARY
TUESDAY NIGHT INTO WEDNESDAY. NAM/GFS IN FAIRLY GOOD AGREEMENT ON
EVOLUTION OF THE FRONT SO WAS COMFORTABLE RAISING POPS FOR THESE
PERIOD. WILL CARRY 50 POPS OUT WEST TO 20 POPS OVER THE COASTAL
PLAINS TUESDAY NIGHT WITH 40 POPS OVER LAND ON WEDNESDAY.
CONVECTIVE ACTIVITY WILL BE HIGHLY DEPENDENT ON WHERE FRONT ENDS
UP AND HOW LONG IT LINGERS OVER THE CWA. THESE DETAILS WILL BE
FINE TUNED OVER THE NEXT SEVERAL DAYS. UPPER LOW WILL BE MOVING
OUT OF MEXICO AND WEST TEXAS TO THE EAST NORTHEAST THURSDAY INTO
FRIDAY. MOISTURE WILL STILL REMAIN OVER SOUTH TEXAS AS PWAT VALUES
CONTINUE TO BE ABOVE NORMAL FOR THIS TIME OF YEAR. SHOWER AND
THUNDERSTORM CHANCES WILL CONTINUE FOR THE SECOND HALF OF THE WORK
WEEK. HAVE ALSO RAISED POPS DURING THE THURSDAY NIGHT AND FRIDAY
TIME FRAME. OVERALL...A WET PERIOD MAY MATERIALIZE ACROSS SOUTH
TEXAS THIS UPCOMING WEEK WITH PERIODS OF LOCALLY HEAVY RAINFALL
POSSIBLE. AFTERNOON HIGH TEMPERATURES WEDNESDAY THROUGH FRIDAY
WILL BE AT OR BELOW NORMAL FOR THIS TIME OF YEAR DUE TO CLOUD
COVER AND PRECIP CHANCES. UPPER SYSTEM WILL BEGIN TO MOVE
NORTHEAST OF THE REGION ON SATURDAY...WITH RAIN CHANCES ENDING
FROM WEST TO EAST.
MARINE...SCEC CONDITIONS TO PERSIST TONIGHT THROUGH AT LEAST
MONDAY WITH LITTLE CHANGE EXPECTED TO SEA CONDITIONS. AREAS OF
HAZE FROM AGRICULTURAL FIRES IN MEXICO MAY EXIST MONDAY ACROSS THE
OPEN WATERS OF THE MIDDLE TEXAS COAST. A LATE SEASON COLD FRONT
AND STRONG UPPER LEVEL WEATHER DISTURBANCE MAY AFFECT THE AREA BY
THE MIDDLE OF THIS WEEK WITH SHOWER AND THUNDERSTORM CHANCES
INCREASING AT TIME.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 74 92 74 89 72 / 10 10 10 10 20
VICTORIA 70 92 72 87 70 / 10 10 10 20 20
LAREDO 75 101 75 94 72 / 10 10 20 10 40
ALICE 72 97 73 91 71 / 10 10 10 10 30
ROCKPORT 76 86 76 85 76 / 10 10 10 10 20
COTULLA 72 99 71 91 70 / 10 20 30 20 50
KINGSVILLE 74 96 75 90 73 / 10 10 10 10 20
NAVY CORPUS 75 86 76 86 75 / 10 10 10 10 20
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
TE/81...AVIATION
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
904 PM CDT TUE MAY 8 2012
.UPDATE...
UPPER TROF AXIS DRIFTING SOUTHEAST ACROSS THE AREA AT THIS TIME.
COLD TEMPS ALOFT SUPPORTED A GOOD DEAL OF LATE AFTERNOON SHOWERS
AND ISOLATED THUNDERSTORMS...BUT THE NEGATIVE DIURNAL TRENDS HAVE
BEEN MORE DRAMATIC THAN PREVIOUSLY EXPECTED. LOW LEVELS REMAIN
VERY DRY AND COMBINED WITH THE LACK OF SUNSHINE HAVE NEARLY ENDED
ALL THE SHOWERS ACROSS THE AREA BY MID EVENING. CLOUDS REMAIN
BASED UP AROUND 8-10KFT. AT THE SFC...THERE IS A SFC LOW IN THE
SHEBOYGAN VCNTY WITH A TROF/CDFNT STRETCHING NORTHWEST THROUGH
ABOUT EAU CLAIRE IN NORTHWEST WISCONSIN. THIS TROF WILL SWING
SOUTH THROUGH THE FORECAST AREA OVERNIGHT. WE TRIMMED POPS
SIGNIFICANTLY EARLIER ON THE SHIFT...AND WILL HANG ONTO A SLIGHT
CHANCE AS THE TOF SWINGS THROUGH. WINDS SWINGING AROUND TO THE
NORTH NORTHEAST SHOULD BRING A MORE SOLID CLOUD DECK LATER TONIGHT
THAT WILL HANG IN THROUGH WEDNESDAY MORNING. CU RULE LOOKS PRETTY
CLOUDY THROUGH EARLY AFTERNOON...THEN SUPPORTS MORE SUNSHINE AS
THE MOISTURE MIXES OUT DURING THE AFTERNOON.
&&
.AVIATION/06Z TAFS/...
UPPER TROF AXIS IS DRIFTING SOUTHEAST THROUGH THE AREA AT THIS
TIME. AT THE SURFACE...A WEAK SURFACE LOW IS LOCATED AROUND
SHEBOYGAN WITH A TROF/COLD FRONT EXTENDING NORTHWEST THROUGH EAU
CLAIRE. THAT TROF WILL DRIFT SOUTH THROUGH THE TAF SITES OVERNIGHT
AND COULD BRING A PERIOD OF MVFR CIGS IN ITS WAKE FROM LATE
TONIGHT THROUGH MID MORNING OR SO ON WEDNESDAY. THE SHOWERS HAVE
NEARLY ENDED...BUT WILL HANG ONTO A SLIGHT CHANCE OVERNIGHT AS THE
TROF DROPS THROUGH. WINDS WILL SHIFT FROM WESTERLY TO NORTH
NORTHEAST BEHIND THE COLD FRONT. AS THE DAY PROGRESSES ON
WEDNESDAY...MIXING WILL LIFT THE CIGS THROUGH THE MORNING AND
SHOULD EVENTUALLY SCATTER OUT THE CIGS BY MID TO LATE AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 318 PM CDT TUE MAY 8 2012/
TONIGHT AND WEDNESDAY...FORECAST CONFIDENCE...MEDIUM TO HIGH
500MB SHORTWAVE TROUGH CONTINUES TO SLIDE SOUTHEAST ACROSS MINNESOTA
AND NORTHWEST WISCONSIN. THIS FEATURE HAS 500MB TEMPERATURES OF 24
TO 27 BELOW ZERO CELSIUS PER RUC ANALYSIS IN ITS CORE FROM SOUTHWEST
MINNESOTA TO NORTHERN WISCONSIN. IN ADDITION...STEEP LOW TO MID
LEVEL LAPSE RATES WITH LOW LEVEL MLCAPES OF A HUNDRED OR SO J/KG
SEEN ACROSS THIS AREA. THESE FEATURES HELPING GENERATE SCATTERED TO
NUMEROUS SHOWERS...WHICH ARE ENTERING THE WESTERN AND NORTHWESTERN
COUNTIES.
THESE SHOULD CONTINUE TO SPREAD EAST SOUTHEAST ACROSS THE FORECAST
AREA LATE THIS AFTERNOON AND EARLY THIS EVENING...WITH PASSAGE OF
SHORTWAVE TROUGH. ISOLATED THUNDER POSSIBLE AS WELL...WITH A FEW
LIGHTNING STRIKES SEEN TO THE NORTHWEST OF THE AREA EARLIER TODAY.
LOW FREEZING LEVELS MAY ALLOW FOR SOME GRAUPEL OR SMALL HAIL TO FALL
WITH A STORM. MAIN SURFACE TROUGH DOES NOT SHIFT SOUTH THROUGH THE
AREA UNTIL LATER TONIGHT...SO NOT CONCERNED ABOUT COLD AIR FUNNELS.
AFTER SHORTWAVE TROUGH SWINGS THROUGH BY 06Z WEDNESDAY...ANOTHER
VORTICITY MAXIMUM SLIDES SOUTH THROUGH THE AREA LATE TONIGHT AND
EARLY WEDNESDAY MORNING. ALTHOUGH LOW CLOUDS ARE EXPECTED TO MOVE
INTO THE AREA LATER TONIGHT AND INTO WEDNESDAY MORNING IN THE
EAST...NOT SEEING MUCH MOISTURE ABOVE THIS LAYER TO WARRANT ANYTHING
MORE THAN ISOLATED SHOWERS AFTER MIDNIGHT...WITH WEDNESDAY MORNING
DRY.
CLOUDS GRADUALLY LIFT AND SCATTER OUT BY THE AFTERNOON FROM WEST TO
EAST ACROSS THE AREA...WITH HIGH PRESSURE BRINGING QUIET WEATHER.
PRESSURE GRADIENT WEAKENS ENOUGH FOR WINDS TO VEER NORTHEAST NEAR
THE LAKE IN THE AFTERNOON. HIGHS SHOULD RISE INTO THE UPPER 50S
LAKESIDE...TO THE LOWER TO MID 60S INLAND PER 925MB TEMPERATURES.
WEDNESDAY NIGHT THROUGH FRIDAY...FORECAST CONFIDENCE...MEDIUM TO HIGH
HIGH PRESSURE CENTERED OVER ILLINOIS WEDNESDAY NIGHT WILL SLOWLY
DRIFT EASTWARD TO THE OHIO RIVER VALLEY BY FRIDAY EVENING. THIS WILL
BRING FAIR WEATHER TO SOUTHERN WISCONSIN THROUGH THIS PERIOD...WITH
ONLY A FEW MID AND HIGH LEVEL CLOUDS PASSING THROUGH AT TIMES.
925 MB TEMPS ANTICIPATED TO INCREASE TO AROUND 14-15C BY THU
AFTERNOON...THEN TO UP TO 18C BY FRI AFTERNOON. WITH A GOOD AMOUNT
OF SUNSHINE EXPECTED...SHOULD BE A NICE COUPLE OF DAYS WITH HIGH
TEMPS RISING TO A FEW DEGREES ABOVE NORMAL BY FRIDAY. LIGHT WINDS
THURSDAY SHOULD ALLOW A LAKE BREEZE TO PUSH INLAND...KEEPING THINGS
COOLER NEAR THE LAKE. AN APPROACHING TROUGH OF LOW PRESSURE FRIDAY
MAY INCREASE SOUTHWEST WINDS ENOUGH TO KEEP THE LAKE BREEZE OFF
SHORE. TEMPS WERE THUS BUMPED UP A BIT NEAR THE LAKE.
FRIDAY NIGHT AND SATURDAY...FORECAST CONFIDENCE...MEDIUM
WEAK SFC TROUGH AND COLD FRONT TO SLIDE THOUGH FRIDAY NIGHT AND INTO
SATURDAY. LIFT NOT THAT GREAT OVERALL...BUT GFS PRECIPITABLE WATER
VALUES DO GET UP OVER AN INCH...SO KEPT SOME LOW POPS GOING. A
LITTLE BIT OF ELEVATED CAPE IN THE GFS SOUNDINGS...SO LEFT A SLIGHT
CHANCE OF THUNDER IN THE FORECAST AS WELL. TEMPS SHOULD BE COOLER ON
SATURDAY BEHIND THE FRONT...ESPECIALLY IF CLOUDS AND SHOWERS LINGER
THROUGH THE MORNING HOURS.
SUNDAY THROUGH TUESDAY...FORECAST CONFIDENCE...MEDIUM TO HIGH
HIGH PRESSURE GENERALLY EXPECTED FOR SUNDAY THROUGH TUESDAY...WITH
MOSTLY SUNNY TO PARTLY CLOUDY SKIES AND NEAR NORMAL TEMPERATURES.
LOOKS LIKE A PRETTY NICE START TO NEXT WEEK.
AVIATION/00Z TAFS/...
SCATTERED TO NUMEROUS RAIN SHOWERS WILL DEVELOP BY 00Z WEDNESDAY
ACROSS TAF SITES...AND LINGER TO AROUND 03Z TO 04Z WEDNESDAY...AS
UPPER LEVEL DISTURBANCE PASSES THROUGH AREA. BROKEN TO NEARLY
OVERCAST VFR CEILINGS ARE EXPECTED LATE THIS AFTERNOON AND EVENING
AS WELL. GUSTY WEST WINDS LATE THIS AFTERNOON WILL WEAKEN BY EARLY
THIS EVENING...AND VEER NORTHWEST TO NORTH LATER TONIGHT WITH
PASSAGE OF SURFACE WIND SHIFT.
CEILINGS WILL LOWER TO MVFR BY 08Z TO 09Z WEDNESDAY ACROSS TAF
SITES...AND SHOULD LINGER UNTIL AROUND 15Z WEDNESDAY BEFORE MIXING
UP TO VFR LEVELS. BROKEN VFR DIURNAL CUMULUS SHOULD THEN LINGER
THROUGH THE REST OF THE DAY. NORTH WINDS AROUND 10 KNOTS ARE
EXPECTED THROUGH THE REST OF WEDNESDAY...VEERING NORTHEAST TO EAST
IN THE AFTERNOON AT MILWAUKEE AND KENOSHA.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...DAVIS
TONIGHT/WEDNESDAY AND AVIATION/MARINE...WOOD
WEDNESDAY NIGHT THROUGH TUESDAY...DDV
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1248 PM CDT MON MAY 7 2012
.UPDATE...DRIER AIR WORKING IN LOW-MID LEVELS HELPING TO ERODE STRATUS
FROM WEST TO EAST. THIS IS HAPPENING A BIT FASTER THAN ORIGINALLY
FORECAST SO HAD TO UPDATE TRENDS IN BOTH SKY COVER AND TEMPS. ALSO
WIPED OUT SHRA CHANCES THIS AFTERNOON EXCEPT IN THE FAR
SOUTHEAST...WHERE BETTER MOISTURE AND LOW LEVEL CONVERGENCE NEAR
SURFACE TROUGH MAY HELP SOME SHOWERS HANG ON INTO THE AFTERNOON.
&&
.AVIATION/18Z TAFS/...LIGHT RAIN WILL EXIT FAR SOUTHEAST WISCONSIN
BY THE THE MIDDLE OF THIS AFTERNOON AS LOW PRESSURE PULLS AWAY TO
THE EAST. MVFR CIGS TO LINGER INTO THE AFTERNOON...FINALLY
EXITING THE EAST EARLY THIS EVENING. SHOULD SEE VFR CONDITIONS
THEN THROUGH TONIGHT AND INTO TOMORROW.
UPPER WAVE EXPECTED TO DROP INTO SOUTHERN WISCONSIN TUESDAY
AFTERNOON...BRINGING A CHANCE OF RAIN SHOWERS WITH A FEW RUMBLES
OF THUNDER POSSIBLE AS WELL. ENOUGH DRY AIR IN THE LOWER LEVELS TO
SUGGEST THAT CIGS WILL STAY VFR AS THE WAVE MOVES THROUGH...THOUGH
MVFR CONDITIONS NOT OUT OF THE QUESTION WITHIN ANY HEFTIER
SHOWERS.
&&
.PREV DISCUSSION... /ISSUED 330 AM CDT MON MAY 7 2012/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
THE STRONG 250 MB JET MAX OF 120 KNOTS HAS PUSHED OFF TO SOUTHERN
QUEBEC WITH A WEAKER JET MAX IN THE UPSTREAM OF THE TROUGH THAT
EXTENDS FROM LAKE WINNIPEG TO THE CENTRAL ROCKIES. ONLY WEAK UPPER
DIVERGENCE TODAY ACROSS WISCONSIN...WHICH HEADS OFF TO THE EASTERN
GREAT LAKES LATE TONIGHT.
A WEAKENING 30 KNOT 700 MB FLOW ACROSS NORTHERN ILLINOIS AND THE
WISCONSIN BORDER AREA EARLY THIS MORNING DIMINISHES TO 10 KNOTS
JUST AFTER SUNRISE.
WEAK 700 MB UPWARD MOTION OF 2.2 MICROBARS/SEC ACROSS LAKE
MICHIGAN JUST AFTER SUNRISE NEAR THE WEAK 700 MB TROUGH AXIS. THEN
LITTLE LIFT LATER THIS MORNING AS AN OCCLUDED FRONT PUSHES EAST
ACROSS THE FORECAST AREA.
THE NAM AND THE 03Z LOCAL WRF KEEP MOST OF THE PRECIPITATION
ACROSS NORTHERN ILLINOIS EARLY THIS MORNING CLOSER TO THE SURFACE
BOUNDARY AND SURFACE LOW. THE NAM/LOCAL WRF/ RAP/AND HRRR ALL
BRING SOME SCATTERED LIGHT SHOWERS ACROSS THE FAR SOUTH THIS
MORNING.
STRONG 700 MB DRYING WILL OCCUR LATE THIS MORNING OVER NORTHWEST
SECTIONS OF THE FORECAST AREA...AND ACROSS ALL OF SOUTHERN
WISCONSIN THIS AFTERNOON. THE DRYING OCCURS AT 850 MB AS
WELL...ALTHOUGH SOME INCREASE IN RH AT 850 OCCURS OVER THE
NORTHERN SECTIONS TONIGHT AHEAD OF THE APPROACHING MID LEVEL
TROUGH THAT EXTENDS FROM THE MINNESOTA ARROWHEAD TO SOUTHEAST
SOUTH DAKOTA BY SUNRISE SATURDAY.
SURFACE DEWPOINTS ALSO DRY...ESPECIALLY TONIGHT AS THEY LOWER
INTO THE LOWER 40S.
SHORT TERM...TUESDAY THROUGH WEDNESDAY NIGHT...FORECAST
CONFIDENCE IS MEDIUM TO HIGH.
SHORT TERM MODELS CONTINUE TO SHOW UPPER LEVEL TROUGH SWINGING
SOUTHEAST THROUGH THE REGION TUESDAY THROUGH WEDNESDAY. APPEARS
BEST CHANCES FOR SHOWERS WILL BE TUESDAY AFTERNOON INTO TUESDAY
EVENING...WITH BEST DIFFERENTIAL CYCLONIC VORTICITY ADVECTION
PASSING THROUGH. CHANCES LOWER LATER TUESDAY NIGHT INTO
WEDNESDAY...WITH SECONDARY VORTICITY MAXIMUM PASSING THROUGH THE
AREA.
AREA FORECAST SOUNDINGS SHOWING STEEP LOW TO MID LEVEL LAPSE
RATES TUESDAY AS THE TROUGH MOVES INTO THE REGION. NAM MORE ROBUST
ON MEAN LAYER CAPES THAN GFS...UP TO 200 J/KG.
HOWEVER...INSTABILITY BARELY REACHING 10 DEGREE BELOW ZERO CELSIUS
ISOTHERM NEEDED FOR CONVECTION. WILL CONTINUE TO MENTION LOW
CHANCES FOR THUNDER TUESDAY AFTERNOON DESPITE MIXED CONFIDENCE IN
ITS OCCURRENCE.
CONTINUED LOWER END POPS TUESDAY NIGHT INTO WEDNESDAY...ESPECIALLY
IN THE EASTERN PORTIONS OF THE AREA. TEMPERATURES WILL BE NEAR TO
JUST BELOW SEASONAL NORMALS DURING THIS TIME...WITH A LAKE BREEZE
EXPECTED WEDNESDAY AFTERNOON. HIGH PRESSURE PASSING OVER THE AREA
WEDNESDAY NIGHT WILL BRING QUIET WEATHER AND COOL TEMPERATURES.
LONG TERM...THURSDAY THROUGH SUNDAY...FORECAST CONFIDENCE IS
MEDIUM.
ECMWF/GFS IN DECENT AGREEMENT DURING THIS PERIOD WITH FEATURES.
THEY SHOW UPPER RIDGING SHIFTING THROUGH THE REGION THURSDAY AND
THURSDAY NIGHT...WITH HIGH PRESSURE SLOWLY SLIDING SOUTHEAST OF
THE AREA. QUIET WEATHER IS EXPECTED TO CONTINUE...WITH
TEMPERATURES NEAR SEASONAL NORMALS.
GFS THEN BRINGS COLD FRONT SOUTHEAST THROUGH THE REGION QUICKER
THAN THE ECMWF...MAINLY FRIDAY AFTERNOON THROUGH FRIDAY EVENING.
ECMWF IS ABOUT 12 HOURS SLOWER WITH THIS FRONTAL PASSAGE.
VORTICITY MAXIMUM SLIDES THROUGH THE AREA WITH THE FRONT.
THUS...WENT WITH A CONSENSUS BLEND FOR POPS AND TEMPERATURES
FRIDAY THROUGH SATURDAY NIGHT.
MODELS THEN SHOW PASSING VORTICITY MAXIMA WITHIN WEST TO NORTHWEST
UPPER LEVEL FLOW. SOME DIFFERENCES WITH TIMING AND PLACEMENT OF
THESE FEATURES...SO WENT WITH CONSENSUS BLEND FOR POPS AND
TEMPERATURES DURING THIS PERIOD AS WELL.
AVIATION/12Z TAFS/...
EXPECT MVFR WITH SOME IFR/LIFR CIGS THIS MORNING. CEILINGS SHOULD
RISE TO VFR THIS AFTERNOON AS DRIER AIR MOVES IN BEHIND AN
OCCLUDED FRONT.
MARINE...
THE PERSISTENT EAST FLOW SHOULD BECOME NORTH THIS MORNING THEN
NORTHWEST TONIGHT. WINDS/WAVES WILL REMAIN BELOW SMALL CRAFT
CRITERIA.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...WIMBERLEY/DDV
TODAY/TONIGHT AND AVIATION/MARINE...HENTZ
TUESDAY THROUGH SUNDAY...WOOD
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
330 AM CDT MON MAY 7 2012
.TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
THE STRONG 250 MB JET MAX OF 120 KNOTS HAS PUSHED OFF TO SOUTHERN
QUEBEC WITH A WEAKER JET MAX IN THE UPSTREAM OF THE TROUGH THAT
EXTENDS FROM LAKE WINNIPEG TO THE CENTRAL ROCKIES. ONLY WEAK UPPER
DIVERGENCE TODAY ACROSS WISCONSIN...WHICH HEADS OFF TO THE EASTERN
GREAT LAKES LATE TONIGHT.
A WEAKENING 30 KNOT 700 MB FLOW ACROSS NORTHERN ILLINOIS AND THE
WISCONSIN BORDER AREA EARLY THIS MORNING DIMINISHES TO 10 KNOTS
JUST AFTER SUNRISE.
WEAK 700 MB UPWARD MOTION OF 2.2 MICROBARS/SEC ACROSS LAKE
MICHIGAN JUST AFTER SUNRISE NEAR THE WEAK 700 MB TROUGH AXIS. THEN
LITTLE LIFT LATER THIS MORNING AS AN OCCLUDED FRONT PUSHES EAST
ACROSS THE FORECAST AREA.
THE NAM AND THE 03Z LOCAL WRF KEEP MOST OF THE PRECIPITATION
ACROSS NORTHERN ILLINOIS EARLY THIS MORNING CLOSER TO THE SURFACE
BOUNDARY AND SURFACE LOW. THE NAM/LOCAL WRF/ RAP/AND HRRR ALL
BRING SOME SCATTERED LIGHT SHOWERS ACROSS THE FAR SOUTH THIS
MORNING.
STRONG 700 MB DRYING WILL OCCUR LATE THIS MORNING OVER NORTHWEST
SECTIONS OF THE FORECAST AREA...AND ACROSS ALL OF SOUTHERN
WISCONSIN THIS AFTERNOON. THE DRYING OCCURS AT 850 MB AS
WELL...ALTHOUGH SOME INCREASE IN RH AT 850 OCCURS OVER THE
NORTHERN SECTIONS TONIGHT AHEAD OF THE APPROACHING MID LEVEL
TROUGH THAT EXTENDS FROM THE MINNESOTA ARROWHEAD TO SOUTHEAST
SOUTH DAKOTA BY SUNRISE SATURDAY.
SURFACE DEWPOINTS ALSO DRY...ESPECIALLY TONIGHT AS THEY LOWER
INTO THE LOWER 40S.
.SHORT TERM...TUESDAY THROUGH WEDNESDAY NIGHT...FORECAST
CONFIDENCE IS MEDIUM TO HIGH.
SHORT TERM MODELS CONTINUE TO SHOW UPPER LEVEL TROUGH SWINGING
SOUTHEAST THROUGH THE REGION TUESDAY THROUGH WEDNESDAY. APPEARS
BEST CHANCES FOR SHOWERS WILL BE TUESDAY AFTERNOON INTO TUESDAY
EVENING...WITH BEST DIFFERENTIAL CYCLONIC VORTICITY ADVECTION
PASSING THROUGH. CHANCES LOWER LATER TUESDAY NIGHT INTO
WEDNESDAY...WITH SECONDARY VORTICITY MAXIMUM PASSING THROUGH THE
AREA.
AREA FORECAST SOUNDINGS SHOWING STEEP LOW TO MID LEVEL LAPSE
RATES TUESDAY AS THE TROUGH MOVES INTO THE REGION. NAM MORE ROBUST
ON MEAN LAYER CAPES THAN GFS...UP TO 200 J/KG.
HOWEVER...INSTABILITY BARELY REACHING 10 DEGREE BELOW ZERO CELSIUS
ISOTHERM NEEDED FOR CONVECTION. WILL CONTINUE TO MENTION LOW
CHANCES FOR THUNDER TUESDAY AFTERNOON DESPITE MIXED CONFIDENCE IN
ITS OCCURRENCE.
CONTINUED LOWER END POPS TUESDAY NIGHT INTO WEDNESDAY...ESPECIALLY
IN THE EASTERN PORTIONS OF THE AREA. TEMPERATURES WILL BE NEAR TO
JUST BELOW SEASONAL NORMALS DURING THIS TIME...WITH A LAKE BREEZE
EXPECTED WEDNESDAY AFTERNOON. HIGH PRESSURE PASSING OVER THE AREA
WEDNESDAY NIGHT WILL BRING QUIET WEATHER AND COOL TEMPERATURES.
.LONG TERM...THURSDAY THROUGH SUNDAY...FORECAST CONFIDENCE IS
MEDIUM.
ECMWF/GFS IN DECENT AGREEMENT DURING THIS PERIOD WITH FEATURES.
THEY SHOW UPPER RIDGING SHIFTING THROUGH THE REGION THURSDAY AND
THURSDAY NIGHT...WITH HIGH PRESSURE SLOWLY SLIDING SOUTHEAST OF
THE AREA. QUIET WEATHER IS EXPECTED TO CONTINUE...WITH
TEMPERATURES NEAR SEASONAL NORMALS.
GFS THEN BRINGS COLD FRONT SOUTHEAST THROUGH THE REGION QUICKER
THAN THE ECMWF...MAINLY FRIDAY AFTERNOON THROUGH FRIDAY EVENING.
ECMWF IS ABOUT 12 HOURS SLOWER WITH THIS FRONTAL PASSAGE.
VORTICITY MAXIMUM SLIDES THROUGH THE AREA WITH THE FRONT.
THUS...WENT WITH A CONSENSUS BLEND FOR POPS AND TEMPERATURES
FRIDAY THROUGH SATURDAY NIGHT.
MODELS THEN SHOW PASSING VORTICITY MAXIMA WITHIN WEST TO NORTHWEST
UPPER LEVEL FLOW. SOME DIFFERENCES WITH TIMING AND PLACEMENT OF
THESE FEATURES...SO WENT WITH CONSENSUS BLEND FOR POPS AND
TEMPERATURES DURING THIS PERIOD AS WELL.
&&
.AVIATION/12Z TAFS/...
EXPECT MVFR WITH SOME IFR/LIFR CIGS THIS MORNING. CEILINGS SHOULD
RISE TO VFR THIS AFTERNOON AS DRIER AIR MOVES IN BEHIND AN
OCCLUDED FRONT.
&&
.MARINE...
THE PERSISTENT EAST FLOW SHOULD BECOME NORTH THIS MORNING THEN
NORTHWEST TONIGHT. WINDS/WAVES WILL REMAIN BELOW SMALL CRAFT
CRITERIA.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...HENTZ
TUESDAY THROUGH SUNDAY...WOOD
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
320 AM EDT WED MAY 9 2012
.SYNOPSIS...
07Z WATER VAPOR AND H4 RUC ANALYSIS SHOWS NORTHERN STREAM FLOW
CONFINED TO OUR NORTH THIS MORNING. FLOW ARRIVES OVER THE
WASHINGTON/BRITISH COLUMBIA COAST AND FORMS LONGWAVE RIDGING OVER
THE INTER-MOUNTAIN WEST/HIGH PLAINS BEFORE DIVING BACK TO THE SOUTH
INTO SHARP LONGWAVE RIDGING DIGGING INTO THE MIDWEST/TN/OH VALLEYS.
THIS TROUGH WILL CONTINUE TO DIG INTO THE EASTERN CONUS AND DRIVE A
LATE SEASON COLD FRONT THROUGH THE FL PENINSULA ON THURSDAY. ACROSS
THE SOUTHERN TIER OF THE COUNTRY WE FIND AN UPPER LOW SPINNING OVER
THE NORTHERN BAJA WHICH IS NOW COMPLETELY CUT-OFF FROM THE MAIN FLOW
AND SLOWLY DRIFTING SOUTHWARD. CLOSER TO HOME...THE FLOW IS
MORE-OR-LESS ZONAL ALONG THE NORTHERN GULF COAST...BUT WILL BECOME
INCREASINGLY CYCLONIC IN NATURE OVER THE NEXT 24 HOURS AS THE TROUGH
TO THE NORTHWEST DIGS INTO THE SOUTHEASTERN STATES.
AT THE SURFACE...FORECAST AREA IS LOCATED BETWEEN THE SUBTROPICAL
RIDGE OVER SOUTH FLORIDA...AND A NEARLY STATIONARY FRONTAL SYSTEM
EXTENDING FROM NEAR THE MS DELTA NORTHEASTWARD ACROSS AL/GA. IT WILL
BE THIS FRONT THAT BECOMES BETTER ORGANIZED WITH TIME AND THEN IS
FORCED SOUTH THROUGH THE REGION ON THURSDAY. HOWEVER...FOR ONE MORE
DAY...OUR LOCAL WEATHER WEATHER/RAIN CHANCES WILL BE CONTROLLED
PRIMARILY BY THE SEA BREEZE.
&&
.SHORT TERM (TODAY THROUGH FRIDAY...
TODAY...AS THE MID/UPPER LEVEL TROUGH DIGS/EVOLVES INTO THE EASTERN
STATES AND THE SURFACE FRONT BEGINS TO MAKE PROGRESS SOUTHWARD...
MASS FIELDS WILL FORCE OUR LOW LEVEL FLOW TO STRENGTHEN. THIS
STRONGER SYNOPTIC FLOW WILL ONLY ACT TO ACCELERATE THE DEVELOPING
SEA BREEZE INLAND DURING THE AFTERNOON HOURS. SIMILAR TO PREVIOUS
DAYS...THIS INLAND PROPAGATION OF THIS BOUNDARY WILL KEEP THE BEST
CONVECTIVE DEVELOPMENT/RAIN CHANCES (30-40%) OVER THE INTERIOR
(GENERALLY WEST OF I-75). THE STRENGTHENING FLOW AND SLOWLY
APPROACHING SYNOPTIC SUPPORT MAY BE ENOUGH TO FORCE A FEW SHOWERS
OVER THE EASTERN GULF THAT WILL APPROACH THE COAST (EVEN IN THE WAKE
OF THE SEA BREEZE)...HOWEVER WATER TEMPERATURES ARE STILL GENERALLY
BELOW 80 DEGREES WHICH SHOULD LIMIT THIS DEVELOPMENT TODAY.
THEREFORE MOST LOCATIONS NEAR THE COAST WILL REMAIN DRY...AND WILL
ONLY GO WITH A SLIGHT CHANCE 20% POP. IN TERMS OF TEMPS...SEE LITTLE
REASON TO DEVIATE MUCH FROM THE MOS NUMBERS WITH UPPER 80S TO 90
INLAND AND LOWER TO MIDDLE 80S AT THE COAST.
TONIGHT...UPPER ENERGY ARRIVING OVER THE EASTERN SEABOARD WILL
RESULT IN CYCLOGENESIS OFF THE MID-ATLANTIC STATES. THE COLD FRONT
EXTENDED SOUTH AND WEST FROM THIS LOW WILL MAKE PROGRESS INTO OUR
REGION AND BE ALIGNED NEAR THE I-4 CORRIDOR BY SUNRISE. WILL LIKELY
SEE A FEW SCATTERED SHOWERS/ISOLATED STORMS ALONG AND AHEAD OF THIS
BOUNDARY GIVEN AT LEAST SOME DEEP LAYER QG FORCING AND LOW LEVEL
FOCUS PROGGED BY THE GFS/ECMWF. HOWEVER THIS SYSTEM WILL BECOME
RATHER ELONGATED WITH TIME AS THE SURFACE LOW RAPIDLY MOVES
NORTHWARD UP THE EAST COAST...AND COMBINED WITH THE DIURNAL MINIMUM
IN CONVECTION SUGGESTS THAT OVERALL COVERAGE OF SHOWERS WILL BE LOW.
CERTAINLY DOES NOT LOOK TO BE A DROUGHT BUSTER.
THURSDAY/THURSDAY NIGHT...COLD FRONT SETTLES INTO SOUTH FLORIDA
DURING THE DAY WHILE ANY LINGERING UPPER LEVEL SUPPORT/DEEP LAYER
MOISTURE MIGRATES SOUTH AND EAST OF OUR FORECAST AREA. SHOULD SEE A
CONTINUATION OF THE SCATTERED SHOWERS THURSDAY MORNING/EARLY
AFTERNOON (GENERALLY SOUTH OF THE I-4 CORRIDOR)...BUT BY THE LATE
AFTERNOON/EARLY EVENING HOURS...MOST OF THIS ACTIVITY WILL BE
CONFINED TO AREAS EAST AND SOUTH OF OUR ZONES. THE OVERNIGHT PERIOD
WILL BE QUIET AND SEASONABLY COOL AS A MUCH DRIER
AIRMASS/ATMOSPHERIC COLUMN DESCENDS ON THE PENINSULA.
FRIDAY...1020+MB SURFACE HIGH PRESSURE WILL MOVE TO THE CAROLINA
COAST PROVIDING A GENERAL EAST/NE SYNOPTIC FLOW INTO THE PENINSULA.
ATMOSPHERIC COLUMN WILL BE FAR TO DRY TO SUPPORT ANY CONVECTION OVER
ALMOST THE ENTIRE AREA...AND WILL LEAVE MENTION OF SHOWERS OUT OF
THE FORECAST. ALTHOUGH 850MB TEMPS IN THE WAKE OF THE FRONT WILL BE
RATHER LOW FOR THIS TIME OF YEAR (11-13C)...GOOD DIURNAL MIXING
SHOULD STILL PROVIDE AFTERNOON HIGHS IN THE MID/UPPER 80S.
&&
.LONG TERM (SATURDAY THROUGH NEXT TUESDAY)...
THE MAIN FEATURE FOR THE EXTENDED PORTION OF THE FORECAST WILL BE AN
UPPER-LEVEL TROUGH FORECAST BY NEARLY ALL MODELS TO DIG TOWARD THE
GULF COAST SUNDAY THROUGH TUESDAY. THE ECMWF AND CANADIAN MODEL KEEP
THE UPPER-TROUGH OPEN THROUGH MONDAY WHILE THE GFS CLOSES OFF A LOW
OVER THE MID-WEST. IN EACH CASE...THE TROUGH AXIS REMAINS TO OUR
WEST WHICH WILL SET UP A FEED OF MOISTURE-RICH AIR ON SOUTHWESTERLY
WINDS ALOFT. THE DEEPER LOW IN THE GFS WOULD BRING MORE UPPER-LEVEL
SUPPORT OVER THE AREA RESULTING IN GREATER OVERALL COVERAGE OF RAIN
WHILE THE MORE ELONGATED POSITIVELY TILTED TROUGH IN THE ECMWF WOULD
RESULT IN MAINLY DIURNALLY DRIVEN SHOWERS AND STORMS WHICH WOULD
FAVOR INLAND LOCATIONS IN THE DEEP WESTERLY FLOW. I DO NOT FAVOR THE
DEEPER GFS SOLUTION BUT CAN NOT COMPLETELY RULE IT OUT EITHER. FOR
THIS REASON...WILL USE A BLEND AND SHOW JUST A SLIGHT CHANCE OF
AFTERNOON SHOWERS ON SUNDAY FOLLOWED BY BETTER SHOWER CHANCES
ESPECIALLY OVER THE NORTHERN HALF OF OUR FORECAST AREA ON MONDAY.
THE GFS WRAPS SOME DRIER AIR INTO THE REGION ON TUESDAY BUT NOT
ENOUGH TO SHUT DOWN RAIN CHANCES.
EITHER WAY...WITH UPPER-LEVEL TROUGHING TO THE WEST AND A DEEP
SOUTHWESTERLY FLOW POTENTIALLY TRANSPORTING DEEP MOISTURE OVER THE
REGION...WE SHOULD SEE 2 OR 3 DAYS OF UNSETTLED WEATHER WITH THE
POTENTIAL FOR SOME BENEFICIAL RAINS EARLY NEXT WEEK.
&&
.AVIATION...
PREDOMINANTLY VFR TODAY WITH SOME CUMULUS/SMALL SHOWERS MOVING IN
OFF THE GULF THIS MORNING. BRIEF MVFR CEILINGS ARE POSSIBLE
ESPECIALLY AROUND PIE AND TPA. OTHERWISE LAL MAY SEE SOME PATCHY FOG
AROUND SUNRISE...THEN SOME SHOWERS AND STORMS AROUND DURING THE
AFTERNOON.
&&
.MARINE...
SOUTHWEST FLOW WILL SLOWLY INCREASE THROUGH THE DAY AHEAD OF AN
APPROACHING COLD FRONT. WINDS WILL REACH CAUTIONARY LEVELS THIS
EVENING FROM TAMPA BAY NORTHWARD ALONG THE NATURE COAST. THE COLD
FRONT WILL THEN SETTLE SOUTHWARD THROUGH THE FORECAST WATERS LATE
TONIGHT INTO THURSDAY. FLOW WILL TURN TO NORTHERLY IN THE WAKE OF
THE FRONT THROUGH THURSDAY NIGHT AND THEN VEER EASTERLY FOR THE
UPCOMING WEEKEND. THE FLOW THIS WEEKEND WILL BE ELEVATED WITH
PERIODS OF CAUTIONARY TO ADVISORY LEVELS WINDS...ESPECIALLY DURING
THE OVERNIGHT AND EARLY MORNING HOURS.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS EXPECTED TODAY AS ABUNDANT LOW LEVEL
MOISTURE KEEPS RELATIVE HUMIDITY ABOVE CRITICAL LEVELS. DRIER AIR
WILL BEGIN TO FILTER INTO THE REGION IN THE WAKE OF A COLD FRONT
DURING THURSDAY. CURRENT FORECAST HAS ENOUGH OF DRIER AIR REACHING
THE NATURE COAST ZONES FOR A BRIEF PERIOD OF NEAR OR BELOW CRITICAL
RELATIVE HUMIDITY THURSDAY AFTERNOON...HOWEVER RED FLAG CONDITIONS
ARE CURRENTLY NOT ANTICIPATED.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 87 72 85 67 / 20 30 30 0
FMY 89 71 86 66 / 20 20 30 0
GIF 89 68 87 66 / 40 30 30 0
SRQ 85 73 83 67 / 20 30 30 0
BKV 86 69 85 61 / 30 30 20 0
SPG 84 74 83 70 / 20 30 30 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/MARINE...MROCZKA
LONG TERM/AVIATION/FIRE WX...JILLSON
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
157 AM EDT WED MAY 9 2012
.AVIATION /06 UTC TAFS/...
UPSTREAM SHORTWAVE COMBINED WITH COLD TEMPS ALOFT SHOULD PROMOTE BKN
CU FIELD TO RAPIDLY DVLP WITH INCREASED TURBULENT MIXING A FEW HOURS
AFTER SUNRISE. LOWER LCL ENVIRONMENT IN LAKE MODIFIED BLYR SHOULD
INITIALLY RESULT IN MVFR CIGS CLOSE TO FUEL ALT/2KFT INVOF
KSBN...HIR FURTHER INLAND. CIGS TO GRDLY RISE WITH INCRSD SFC
HEATING TO DECIDEDLY VFR BY ERLY AFTN. TIMING OF LOBE OF DEEPER
MOISTURE IN ADVOF NCNTL WISCONSIN SHORTWAVE TO DROP SEWD INTO NRN IN
MIDDAY FOR TEMPO PD OF -SHRA AT KFWA WITH HIR PROB FOR DEEPER
CONVECTION...TSRA/CB POTNL...RELEGATED N/NE OF AIRFIELD IN CORE OF
MIDLVL COLD POOL.
&&
.SHORT TERM...
TONIGHT...WEDNESDAY...WEDNESDAY NIGHT...
WATER VAPOR IMAGERY AND LATEST RUC ANALYSIS CLEARLY DEPICTING THE
MAIN FEATURE OF CONCERN IN THE SHORT TERM...DEEP UPPER TROUGH OVER
MN THAT WILL BE DROPPING DOWN ACROSS THE GREAT LAKES REGION TONIGHT
AND WEDNESDAY. AHEAD OF THIS FEATURE WILL BE AN INCREASING SFC
GRADIENT ALONG WITH DRIER AIR IN THE BOUNDARY LAYER AND LOW LEVELS
WHICH SHOULD PRECLUDE ANY SIGNIFICANT FOG REDEVELOPMENT. 12Z RAOBS
SHOWING -25C COLD POOL TO ACCOMPANY TROUGH AND RESULT IN VERY STEEP
MID LEVEL LAPSE RATES BY THE LATE MORNING HOURS. EXPECT THE
DIURNALLY DRIVEN SHRA AND EVEN A FEW TSRA CURRENTLY SEEN OVER MN AND
WI WILL SPREAD OVER THE GREAT LAKES REGION AFTER MIDNIGHT TONIGHT
AND WEDNESDAY. WILL USE THE TRACK OF UPPER TROUGH AND COLD POOL IN
TIMING OF PRECIP CHANCES...BEGINNING IN THE NW CWA AFTER MIDNIGHT
TONIGHT AND CONTINUING IN THE EASTERN HALF THROUGH WEDNESDAY AFTN.
MAGNITUDE OF COLD POOL WILL ALSO FAVOR CONVECTIVE POTENTIAL BY THE
AFTERNOON HOURS...BUFKIT SOUNDINGS SHOWING TT GT 50...SO WILL ALSO
INCLUDE A MENTION OF THUNDER HERE. RESULTING TEMPS WILL BE
CONSIDERABLY COOLER IN THIS PATTERN...5-10F BELOW NORMAL BOTH
WEDNESDAY AND WEDNESDAY NIGHT.
&&
.LONG TERM...
MEAN TROUGHING WILL REDVLP ACRS THE NE CONUS INTO THIS WEEKEND AS
WRN RIDGING AMPLIFIES. THUS W/PATTN REORIENTING TWD YET ANOTHER
PNA...XPC DRY WX TO CONT AS W/NW FLW ALOFT CONTS AND LL RIDGING
PERSISTS ACRS THE GOMEX W/LTL IN WAY OF SIG LL MSTR RTN UNTIL PSBLY
AT THE END OF THE PD ON DY8. TEMPS THROUGH THE PD GENERALLY NR
NORMAL.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SHORT TERM...LOGSDON
LONG TERM...T
AVIATION...MURPHY
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
442 AM EDT WED MAY 9 2012
.SYNOPSIS...
ISSUED AT 441 AM EDT WED MAY 9 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF OVER THE GULF OF
ALASKA...A DOWNSTREAM RIDGE EXTENDING FROM THE ROCKIES TO NUNAVUT
AND A TROF EXTENDING FROM QUEBEC THRU THE WRN GREAT LAKES. WITH A
SLOWLY PROGRESSIVE PATTERN...A QUIET 2-3 DAYS ARE ON THE WAY AS THE
UPSTREAM RIDGE SHIFTS E IN RESPONSE TO TROF MOVING INLAND FROM THE
GULF OF ALASKA. TROF WILL REACH THE UPPER LAKES LATE FRI...BRINGING
THE NEXT CHC OF -SHRA. AFTER A COOL DAY TODAY...A WARMING TREND WILL
GET UNDER WAY THU AND FRI AS WAA PATTERN DEVELOPS AHEAD OF THE TROF.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 441 AM EDT WED MAY 9 2012
WITH TROF AXIS SHIFTING SE OF UPPER MI...BACK EDGE OF
MOISTURE/CLOUDS IS PROGRESSING STEADILY SE ACROSS LAKE SUPERIOR
ATTM. PLENTY OF DRY AIR IN AN ABSOLUTE AND RELATIVE SENSE IS NOTED
UPSTREAM PER 00Z CWPL SOUNDING WHICH SHOWED PRECIPITABLE WATER OF
0.24 INCHES (AROUND 50PCT OF NORMAL) AND DWPT DEPRESSIONS GENERALLY
IN THE 10-25C RANGE FROM THE SFC TO ABOUT 500MB. WITH THE INFLUX OF
DRY AIR...THE FEW -SHRA/SPRINKLES NOTED ON KMQT RADAR WILL END IN
THE NEXT FEW HRS...AND CLOUDS WILL CLEAR OUT FROM NW TO SE TODAY. NOT
MUCH DIURNAL CU WAS NOTED UPSTREAM IN NRN ONTARIO YESTERDAY AFTN.
SHOULD BE A SIMILAR SITUATION HERE TODAY. THIS IDEA IS SUPPORTED BY
THE CU RULE WHICH SUGGESTS SCT DEVELOPMENT EARLIER IN THE DAY BEFORE
MIXING OF DRIER AIR BEGINS TO EAT AWAY AT THE CU. STABILIZING
INFLUENCE OF COOL FLOW OFF LAKE SUPERIOR WILL KEEP DAYTIME CU
INLAND...WITH CU PROGRESSIVELY FARTHER INLAND WITH TIME AS MARINE
LAYER INFLUENCE EXPANDS S. IT WILL BE A COOL DAY WITH 850MB
THERMAL TROF AROUND 0C SLOWLY SLIPPING E DURING THE AFTN. LOCATIONS
ALONG THE LAKE SUPERIOR SHORELINE SHOULD HOLD TO THE LOW/MID
40S...COOLEST OVER THE E. MIXING TO AROUND 800MB YIELDS MAX TEMPS IN
THE UPPER 50S/AROUND 60 TOWARD THE WI BORDER...WHICH IS INLINE WITH
UPSTREAM TEMPS IN NRN ONTARIO YESTERDAY.
AFTER A COOL DAY TODAY...STAGE WILL BE SET FOR A CHILLY/FROSTY
NIGHT TONIGHT AS SFC HIGH PRES RIDGE DRIFTS OVER THE AREA...
RESULTING IN WINDS DIMINISHING TO CALM/NEAR CALM UNDER MOSTLY CLEAR
SKIES. WITH PRECIPITABLE WATER RUNNING 50-75PCT OF NORMAL...
CONTINUED TO LEAN TOWARD THE LOW END OF AVBL GUIDANCE GIVEN THE
FAVORABLE RADIATIONAL COOLING CONDITIONS. TRADITIONAL COLD SPOTS IN
THE INTERIOR...ESPECIALLY W HALF...MAY SLIP INTO THE UPPER 20S. THAT
SAID...ONE POTENTIAL ISSUE THAT MAY LIMIT COOLING IS SOME CLOUD
COVER. MODELS SUGGEST THAT MID CLOUDS CURRENTLY OVER NRN MANITOBA AT
THE NOSE OF SOME WAA COULD DROP SE OVER THE AREA TONIGHT. SINCE THAT
WAA WEAKENS TO THE SE...EXPECT THE MID CLOUDS TO SHOW AT LEAST SOME
DECREASE IN COVERAGE AS THEY HEAD TOWARD THE AREA. OBVIOUSLY...CLOUD
TRENDS UPSTREAM TODAY WILL BE SOMETHING TO MONITOR DUE TO THE
POSSIBLE AFFECT ON MIN TEMPS TONIGHT.
UNDER SUNNY SKIES...A WARMER DAY IS EXPECTED THU WITH HIGH PRES IN
CONTROL AND 850MB TEMPS RISING TO 6 TO 10C BY LATE IN THE DAY. TEMPS
SHOULD REBOUND TO NEAR OR SLIGHTLY ABOVE NORMAL THOUGH LAKE BREEZES
SHOULD RULE LATE MORNING THRU THE AFTN TO PROVIDE COOLING NEAR THE
LAKES. MIXING UPWARDS OF 750MB YIELDS MAX TEMPS AROUND 70F OVER THE
INTERIOR W. TEMPS LAKESIDE WILL BE IN THE 40S/50S...DEPENDING ON HOW
EARLY LAKE BREEZE DEVELOPS AT EACH LOCATION.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 441 AM EDT WED MAY 9 2012
NAM SHOWS A 500 MB RIDGE OVER THE UPPER MISSISSIPPI RIVER VALLEY 00Z
FRI WITH TROUGHING AND A CLOSED LOW OVER NEW ENGLAND AND THE EASTERN
U.S...A CLOSED 500 MB LOW AND TROUGH NEAR IN NE MEXICO...AND A
TROUGH IN THE NORTHERN ROCKIES. THE 500 MB RIDGE MOVES INTO THE
UPPER GREAT LAKES ON FRIDAY. THE SHORTWAVE OVER THE NORTHERN ROCKIES
MOVES INTO THE UPPER GREAT LAKES FRIDAY NIGHT.
NAM BRINGS IN SOME 850-500 MB Q-VECTOR CONVERGENCE WITH DEEPER
MOISTURE MOVING IN FRI AFTERNOON INTO SAT MORNING. GFS AND ECMWF
SHOW THE SAME THING FRI AFTERNOON INTO SAT MORNING. WHAT THAT WILL
MEAN IS CHANCE POPS MOVING ACROSS THE CWA FRIDAY AFTERNOON THROUGH
FRIDAY NIGHT...THEN SATURDAY LOOKS DRY AS THE FRONT AND NARROW BAND
OF PCPN MOVE OUT. REMOVED POPS OVER THE EAST ON SATURDAY AS THE
FRONT IS WELL SOUTH AND EAST OF THE AREA BY THEN. THIS IS THE ONLY
CHANGE I MADE IN THE MID TERM. TEMPERATURES LOOKED GOOD AND LEFT
THEM ALONE FOR THE MOST PART.
IN THE EXTENDED...PROLONGED DRY PERIOD CONTINUES WITH THE NEXT
CHANCE FOR PCPN LATE ON TUESDAY. ECMWF SHOWS THE UPPER GREAT LAKES
STAYING IN A BROAD 500 MB TROUGH...BUT ALL THE DYNAMICS STAY NORTH
OF THE AREA UNTIL A TROUGH DIGS TO THE SOUTHEAST LATE ON TUESDAY.
TEMPERATURES THIS PERIOD LOOK TO BE NEAR NORMAL TO SLIGHTLY ABOVE
NORMAL WITH A SLOW WARMING TREND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 139 AM EDT WED MAY 9 2012
AN UPPER LEVEL DISTURBANCE MOVING ACROSS THE AREA COULD BRING SOME
-SHRA/-DZ TO KSAW OVERNIGHT BUT OTHERWISE EXPECT DRY CONDITIONS
ELSEWHERE. LINGERING LOW-LVL MOISTURE WILL RESULT IN MVFR CIGS
OVERNIGHT INTO EARLY WED...BUT THERE WILL BE A PERIOD OF IFR
CONDITIONS AT KIWD AND KSAW WHERE NORTH WINDS AND FAVORABLE UPSLOPE
FLOW COULD STILL RESULT IN A PERIOD OF STRATUS AND POSSIBLE FOG
OVERNIGHT.
DRIER AIR MOVING IN FROM THE NORTH WILL LEAD TO QUICKLY IMPROVING
CONDITIONS TO VFR BY MID MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 441 AM EDT WED MAY 9 2012
THE DENSE FOG OVER THE LAKE LOOKS TO BE DONE AS NO SHIP OBS OR
OBSERVATION HAVE SHOWN IT THE PAST FEW HOURS AND CARIBOU ISLAND HAS
A 6 DEGREE TEMP/DEW POINT SPREAD. THE DRIER AIR HAS MOVED OVER THE
LAKE AND HELPED TO DISSIPATE THE FOG. LACK OF SIGNIFICANT WEATHER
FEATURES WILL RESULT IN WINDS MOSTLY UNDER 20KT ACROSS LAKE SUPERIOR
THRU THE END OF THE WEEK. NO GALES SEEN ANYTIME SOON.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...NONE.
LAKE SUPERIOR...NONE.
LAKE MICHIGAN...NONE.
&&
$$
SYNOPSIS...ROLFSON
SHORT TERM...ROLFSON
LONG TERM...07
AVIATION...VOSS
MARINE...07
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
141 AM EDT WED MAY 9 2012
.SYNOPSIS...
ISSUED AT 429 PM EDT TUE MAY 8 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH AXIS
FROM JAMES BAY THROUGH WRN LAKE SUPERIOR TO ERN MN. AT THE SFC...A
TROUGH EXTENDED FROM SE LAKE SUPERIOR THROUGH CNTRL UPPER MI INTO
WRN WI. THE COMBINATION OF DIURNAL HEATING...STEEP MID LEVEL LAPSE
RATES AND WEAK TO MODERATE QVECTOR CONV ASSOCIATED WITH THE MID
LEVEL TROUGH HAS SUPPORTED SCT/NMRS SHRA OVER MOST OF INLAND UPPER
MI. IN ADDITION...SOME ISOLD TSRA WITH SMALL HAIL HAVE ALSO
DEVELOPED. THE GREATEST SHRA COVERAGE AND HEAVIEST RAIN WAS OVER THE SE
CWA WHERE LOW LEVEL CONV WITH THE TROUGH AND LAKE BREEZE WAS MOST
PROMINENT.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 429 PM EDT TUE MAY 8 2012
AS THE MID LEVEL AND SFC TROUGH SHIFTS TO THE SOUTHEAST AND DIURNAL
HEATING SUBSIDES...EXPECT THE AREA OF SHOWERS TO DIMINISH AND SAG TO
THE SOUTH. SHOWERS MAY STILL BE NMRS/WIDESPREAD LATE THIS AFTERNOON
20Z-24Z BUT BY 00Z-03Z...THE REMAINING PCPN SHOULD BECOME SCT/ISOLD
AND END BY AROUND MIDNIGHT. HOWEVER...WITH ABUNDANT LOW LEVEL
MOISTURE REMAINING INCREASING CYCLONIC NE TO N FLOW (9505-850 MB N
WINDS OF 20-30 KT) INTO N CNTRL UPPER MI...HIGHER RES MODELS SUGGEST
LIGHT PCPN WILL DEVELOP IN LINE WITH PREVIOUS FCST.
MODELS SUGGEST THAT THE SHARP BACK EDGE OF THE LOW LEVEL
MOISTURE...PER VIS IMAGERY...WILL MOVE N-S THROUGH THE AREA BTWN
09Z-15Z. SO...ANY PCPN SHOULD END BY EARLY WED WITH PARTLY TO MOSTLY
SUNNY SKIES BY MIDDAY. SUNSHINE/MIXING SHOULD ALLOW INLAND TEMPS TO
CLIMB TO NEAR 60 BUT ONSHORE FLOW NORTH WILL KEEP READINGS IN THE
UPPER 40S TO LOWER 50S NEAR LAKE SUPERIOR.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 429 PM EDT TUE MAY 8 2012
A RIDGE OF HIGH PRESSURE...CENTERED FROM WY TO N MANITOBA WILL BE
PUSHING ACROSS THE UPPER GREAT LAKES WEDNESDAY NIGHT THROUGH FRIDAY
MORNING. WE CONTINUE TO LOOK INTO WEDNESDAY NIGHT/THURSDAY MORNING
AS BEING THE COLDEST TIME PERIOD...WITH LIGHT WINDS AND RELATIVELY
LOW PW VALUES. INCLUDED THE MENTION OF FREEZING TEMPS FOR THE
INTERIOR WEST IN THE HWO.
THE MAIN FEATURE OF INTEREST PRECIPITATION WISE WILL BE THE STACKED
LOW OVER N CENTRAL CANADA FOR THE LATTER HALF OF THE WORK WEEK. THE
LOW ITSELF WILL SLOWLY SHIFT ACROSS HUDSON BAY BY SATURDAY
NIGHT...WHERE IT WILL LIKELY LINGER THROUGH THE REMAINDER OF THE
PERIOD. WAVES ROTATING AROUND THE LOW SHOULD BRING THE INITIAL SFC
TROUGH/COLD FRONT TO FAR W LAKE SUPERIOR AT 18Z FRIDAY...CENTRAL
UPPER MI BY 00Z SATURDAY...AND EAST OF ALL UPPER MI BY 12Z SATURDAY.
TIMING DIFFERS BY 3-5HRS BETWEEN THE VARIOUS MODELS...WITH THE
08/00Z CANADIAN ON THE SLOW END...AND THE 08/00Z ECMWF AND 08/12Z
BEING ON THE QUICKER SOLUTIONS. THE 08/06Z GFS RUNS THE MIDDLE
GROUND BETWEEN THESE VARYING SOLUTIONS. ADDED THE MENTION OF
ISOLATED TS OVER THE WITH SB/MU CAPE VALUES OF 300 TO 600J/KG.
GIVEN THE STRENGTHENING SOUTHERLY WINDS AHEAD OF THE COLD FRONT
FRIDAY AFTERNOON WITH THE PEAK OF DAYTIME HEATING...FIRE WX CONCERNS
MAY INCREASE...PARTICULARLY OVER THE E HALF WHERE MORE LIMITED
HUMIDITY VALUES WILL LIKELY EXIST. WILL ALSO CONTINUE TO HIGHLIGHT
DOWNSLOPE AREAS FOR SOME OF THE WARMER TEMPS ACROSS THE CWA. SOME
GUIDANCE IS HINTING AT THE POTENTIAL OF 80 DEGREES OVER THE BARAGA
PLAINS FRIDAY.
EXPECT SHOWERS TO COME TO AN END SATURDAY MORNING...WITH DRY WEATHER
THEN TAKING HOLD THROUGH TUESDAY. GIVEN W TO NW FLOW ALOFT...THERE
COULD BE A SMALLER CHANCE OF SHOWERS...BUT WILL NOT INCLUDE AT THIS
TIME GIVEN THE LOW PROBABILITY...WITH HIGH PRESSURE SLIDING IN FROM
THE N/CENTRAL PLAINS. MODELS ARE NOT DOING THE BEST AT COMING
TOGETHER ON A SOLUTION FOR MONDAY...WITH THE POTENTIAL OF ANOTHER
COLD FRONT MOVING NW TO SE OVER THE CWA /LIKE THE 08/12Z ECMWF/.
THIS MAY BE ONE AREA OF THE FCST THAT CHANGES MORE THAN ANY OTHER
OVER THE NEXT SEVERAL DAYS. OTHERWISE...HIGHS IN THE 60S INLAND FROM
THE GREAT LAKES LOOK TO BE THE RULE FROM SUNDAY THROUGH NEXT TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 139 AM EDT WED MAY 9 2012
AN UPPER LEVEL DISTURBANCE MOVING ACROSS THE AREA COULD BRING SOME
-SHRA/-DZ TO KSAW OVERNIGHT BUT OTHERWISE EXPECT DRY CONDITIONS
ELSEWHERE. LINGERING LOW-LVL MOISTURE WILL RESULT IN MVFR CIGS
OVERNIGHT INTO EARLY WED...BUT THERE WILL BE A PERIOD OF IFR
CONDITIONS AT KIWD AND KSAW WHERE NORTH WINDS AND FAVORABLE UPSLOPE
FLOW COULD STILL RESULT IN A PERIOD OF STRATUS AND POSSIBLE FOG
OVERNIGHT.
DRIER AIR MOVING IN FROM THE NORTH WILL LEAD TO QUICKLY IMPROVING
CONDITIONS TO VFR BY MID MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 429 PM EDT TUE MAY 8 2012
ABUNDANT LOW-LEVEL MOISTURE AND LIGHT CONVERGENT WIND FLOW HAS LEAD
TO AREAS OF FOG (DENSE AT TIMES) ACROSS LAKE SUPERIOR. THUS DENSE
FOG ADVY CONTINUES FOR MUCH OF THE LAKE. FOG WILL LIFT TONIGHT AS
DRIER AIR ARRIVES FROM THE N.
LACK OF SIGNIFICANT WEATHER FEATURES WILL RESULT IN WINDS MOSTLY
UNDER 20KT ACROSS LAKE SUPERIOR THRU THE END OF THE WEEK. THE
STRONGER WINDS THIS WEEK WILL OCCUR THIS EVENING INTO WED OVER
ERN LAKE SUPERIOR AS A LOW PRES TROF EXITS THE AREA...AND ALSO FRI
AS ANOTHER LOW PRES TROF MOVES ACROSS THE UPPER GREAT LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 2 AM EDT EARLY THIS MORNING FOR LSZ251-
267.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...KF
AVIATION...VOSS
MARINE...JLB
AREA FORECAST DISCUSSION
NWS DULUTH MN
1223 AM CDT WED MAY 9 2012
.AVIATION.../06Z TAF ISSUANCE/
BRIEF PERIOD OF IFR CEILINGS NEAR LAKE SUPERIOR SHOULD ONLY LAST A
COUPLE OF HOURS AS CLEAR SKIES MOVE INTO NORTHERN MINNESOTA. WITH
THE CLEAR SKIES AND LIGHT WINDS...SOME PATCHY FOG FORMATION IS
POSSIBLE OVER THE TERMINALS BEFORE SUNRISE. HAVE TEMPO GROUPS FOR
VISIBILITIES AT 2SM BETWEEN 08Z AND 11Z. VFR CONDITIONS ARE
EXPECTED AFTER DAYBREAK.
&&
.PREV DISCUSSION... /ISSUED 1116 PM CDT TUE MAY 8 2012/
UPDATE...
LATEST IR SAT IMAGERY SHOWS WELL DEFINED CLEARING LINE ADVANCING
FROM THE NORTH. AT 11 PM...THE CLEARING WAS LOCATED ALONG A LINE
FROM KBJI...EAST TO KHIB...AND LUTSEN IN NE MINNESOTA. UNDER THE
CLEAR SKIES TEMPERATURES HAVE FALLING QUICKLY INTO THE MIDDLE 30S.
UPDATED FCST TO LOWER OVERNIGHT TEMPS A FEW DEGREES DUE TO THE
CLEAR SKIES AND LOWER DEWPOINTS ADVECTING IN FROM THE NORTH.
EXPECT A FEW FAVORED LOCATIONS ALONG THE IRON RANGE TO FALL INTO
THE UPPER 20S AROUND DAY BREAK.
PREV DISCUSSION... /ISSUED 720 PM CDT TUE MAY 8 2012/
UPDATE...
REFRESHED EVENING FORECAST BASED ON QUICKLY DIMINISHING RADAR
TRENDS AND ADJUSTED SKY COVER TO REFLECT ADVANCING CLEARING FROM
CANADA. INTRODUCED PATCHY FOG TO ALL ZONES IN ANTICIPATION OF
CLEARING SKIES AND LIGHT WINDS OVERNIGHT RESULTING RADIATIONAL
COOLING/FOG. LATEST NAM BUFR SOUNDINGS SUGGEST BEST CHC FOR FOG
WILL BE ALONG AND SOUTH OF US HIGHWAY 2. NORTH OF THIS
LINE...MUCH DRIER CANADIAN AIR WILL ARRIVE DURING THE EARLY
MORNING HRS.
PREV DISCUSSION... /ISSUED 342 PM CDT TUE MAY 8 2012/
SFC/MID LVL LOW COLLAPSING SOUTHWARD THIS AFTERNOON AS PROGRESSIVE
FLOW ALOFT CONTINUES. ELONGATED SFC TROUGH/CONVERGENCE ZONE HAS BEEN
A RESERVOIR OF LOW LVL INSTABILITY TODAY AS DEPICTED BY RUC13 THETAE
FIELDS IN LOWEST 3/4K FT. UPPER COLD POOL HAS PROVIDED OPPORTUNITY
FOR STEEP LAPSE RATES AND AREAS OF CONVECTION HAVE DEVELOPED. MOST
PERSISTENT PRECIP HAS BEEN LOCATED ALONG/NORTH OF DEEP SHEAR AXIS
ACROSS IRON RANGE...SLOWLY MOVING SOUTH. A FEW REPORTS OF SMALL HAIL
WERE RECEIVED ACROSS WISCONSIN ZONES EARLY THIS AFTERNOON.
TONIGHT...OTHER THAN EARLY EVENING CONVECTION POTENTIAL...CONDITIONS
SHOULD TREND TOWARDS LESS PRECIP AND DECREASING CLOUD COVER FROM
NORTH TO SOUTH. CONFIDENCE NOT HIGH ON BR/FG DEVELOPMENT SO HAVE
LEFT OUT OF GRIDS/ZFP FOR NOW. LOWEST TEMPS SHOULD OCCUR IN
ARROWHEAD WHERE CLEARING OCCURS FIRST.
TOMORROW/TOMORROW NIGHT...SFC/MID LVL RIDGING WILL DOMINATE
WEDNESDAY. EXPECT DECENT WARMING WITH MAX TEMPS NEAR/ABOVE CLIMO.
EXPECT AN AREA OF INCREASING HIGH CLOUDS TO PUSH ACROSS RIDGE AXIS INTO CWA
DURING THE AFTN/EVENING HOURS. TIMING IS A BIT OF A CHALLENGE AS
MDLS DIFFER ON EXTENT/SPEED OF HIGH LVL COND PRESS DEFICITS.
LONG TERM...THURSDAY THROUGH TUESDAY.
MAIN FORECAST CONCERN FOR THE EXTENDED FORECAST PERIOD IS A STRONG
COLD FRONT THAT IS PROGGED TO TRACK ACROSS THE UPPER MIDWEST
FRIDAY/FRIDAY NIGHT. AHEAD OF THE FRONT...A WARM-UP IS EXPECTED FOR
THURSDAY WITH HIGHS IN THE 70S. THE FRONT WILL TAP THIS WARMTH ALONG
WITH INCREASING MOISTURE TO PRODUCE A CHANCE OF SHOWERS AND STORMS
ACROSS THE NORTHLAND FRIDAY AND FRIDAY NIGHT. THE PRECIPITATION WILL
END BY SATURDAY...WITH MAINLY DRY CONDITIONS EXPECTED THROUGH EARLY
NEXT WEEK.
&&
.POINT TEMPS/POPS...
DLH 37 62 42 69 / 10 0 0 0
INL 33 65 41 73 / 10 0 10 0
BRD 39 65 43 75 / 40 0 10 0
HYR 35 64 38 72 / 30 0 0 0
ASX 35 63 39 71 / 10 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
AVIATION...KK
AREA FORECAST DISCUSSION
NWS DULUTH MN
1116 PM CDT TUE MAY 8 2012
.UPDATE...
LATEST IR SAT IMAGERY SHOWS WELL DEFINED CLEARING LINE ADVANCING
FROM THE NORTH. AT 11 PM...THE CLEARING WAS LOCATED ALONG A LINE
FROM KBJI...EAST TO KHIB...AND LUTSEN IN NE MINNESOTA. UNDER THE
CLEAR SKIES TEMPERATURES HAVE FALLING QUICKLY INTO THE MIDDLE 30S.
UPDATED FCST TO LOWER OVERNIGHT TEMPS A FEW DEGREES DUE TO THE
CLEAR SKIES AND LOWER DEWPOINTS ADVECTING IN FROM THE NORTH.
EXPECT A FEW FAVORED LOCATIONS ALONG THE IRON RANGE TO FALL INTO
THE UPPER 20S AROUND DAY BREAK.
&&
.PREV DISCUSSION... /ISSUED 720 PM CDT TUE MAY 8 2012/
UPDATE...
REFRESHED EVENING FORECAST BASED ON QUICKLY DIMINISHING RADAR
TRENDS AND ADJUSTED SKY COVER TO REFLECT ADVANCING CLEARING FROM
CANADA. INTRODUCED PATCHY FOG TO ALL ZONES IN ANTICIPATION OF
CLEARING SKIES AND LIGHT WINDS OVERNIGHT RESULTING RADIATIONAL
COOLING/FOG. LATEST NAM BUFR SOUNDINGS SUGGEST BEST CHC FOR FOG
WILL BE ALONG AND SOUTH OF US HIGHWAY 2. NORTH OF THIS
LINE...MUCH DRIER CANADIAN AIR WILL ARRIVE DURING THE EARLY
MORNING HRS.
PREV DISCUSSION... /ISSUED 638 PM CDT TUE MAY 8 2012/
AVIATION.../00Z TAF ISSUANCE/
DIURNALLY DRIVEN SHOWERS BEGINNING TO DIMINISH FROM NORTH TO
SOUTH. CLOUDS SCATTER NORTH OF THE INTERNATIONAL BORDER AND WILL
MOVE INTO THE TERMINALS LATER TONIGHT. SOME FOG PATCHES MAY OCCUR
AFTER 06Z AS THE SKIES PARTIALLY CLEAR. SKIES WILL ME MOSTLY CLEAR
FOR WEDNESDAY WITH NORTHWEST WINDS AROUND 10 KNOTS.
PREV DISCUSSION... /ISSUED 342 PM CDT TUE MAY 8 2012/
SFC/MID LVL LOW COLLAPSING SOUTHWARD THIS AFTERNOON AS PROGRESSIVE
FLOW ALOFT CONTINUES. ELONGATED SFC TROUGH/CONVERGENCE ZONE HAS BEEN
A RESERVOIR OF LOW LVL INSTABILITY TODAY AS DEPICTED BY RUC13 THETAE
FIELDS IN LOWEST 3/4K FT. UPPER COLD POOL HAS PROVIDED OPPORTUNITY
FOR STEEP LAPSE RATES AND AREAS OF CONVECTION HAVE DEVELOPED. MOST
PERSISTENT PRECIP HAS BEEN LOCATED ALONG/NORTH OF DEEP SHEAR AXIS
ACROSS IRON RANGE...SLOWLY MOVING SOUTH. A FEW REPORTS OF SMALL HAIL
WERE RECEIVED ACROSS WISCONSIN ZONES EARLY THIS AFTERNOON.
TONIGHT...OTHER THAN EARLY EVENING CONVECTION POTENTIAL...CONDITIONS
SHOULD TREND TOWARDS LESS PRECIP AND DECREASING CLOUD COVER FROM
NORTH TO SOUTH. CONFIDENCE NOT HIGH ON BR/FG DEVELOPMENT SO HAVE
LEFT OUT OF GRIDS/ZFP FOR NOW. LOWEST TEMPS SHOULD OCCUR IN
ARROWHEAD WHERE CLEARING OCCURS FIRST.
TOMORROW/TOMORROW NIGHT...SFC/MID LVL RIDGING WILL DOMINATE
WEDNESDAY. EXPECT DECENT WARMING WITH MAX TEMPS NEAR/ABOVE CLIMO.
EXPECT AN AREA OF INCREASING HIGH CLOUDS TO PUSH ACROSS RIDGE AXIS INTO CWA
DURING THE AFTN/EVENING HOURS. TIMING IS A BIT OF A CHALLENGE AS
MDLS DIFFER ON EXTENT/SPEED OF HIGH LVL COND PRESS DEFICITS.
LONG TERM...THURSDAY THROUGH TUESDAY.
MAIN FORECAST CONCERN FOR THE EXTENDED FORECAST PERIOD IS A STRONG
COLD FRONT THAT IS PROGGED TO TRACK ACROSS THE UPPER MIDWEST
FRIDAY/FRIDAY NIGHT. AHEAD OF THE FRONT...A WARM-UP IS EXPECTED FOR
THURSDAY WITH HIGHS IN THE 70S. THE FRONT WILL TAP THIS WARMTH ALONG
WITH INCREASING MOISTURE TO PRODUCE A CHANCE OF SHOWERS AND STORMS
ACROSS THE NORTHLAND FRIDAY AND FRIDAY NIGHT. THE PRECIPITATION WILL
END BY SATURDAY...WITH MAINLY DRY CONDITIONS EXPECTED THROUGH EARLY
NEXT WEEK.
&&
.POINT TEMPS/POPS...
DLH 37 62 42 69 / 10 0 0 0
INL 33 65 41 73 / 10 0 10 0
BRD 39 65 43 75 / 40 0 10 0
HYR 35 64 38 72 / 30 0 0 0
ASX 35 63 39 71 / 10 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...GRANING
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
135 AM EDT WED MAY 9 2012
.SYNOPSIS...
A STRONG COLD FRONT WILL APPROACH FROM THE WEST OVERNIGHT AND
BRING SHOWERS AND THUNDERSTORMS TO THE AREA WEDNESDAY AND
WEDNESDAY NIGHT. COOL AND DRY HIGH PRESSURE WILL BUILD INTO THE
AREA THURSDAY AND PERSIST THROUGH THE WEEKEND. THE HIGH WILL SLIP
OFF THE COAST BY LATE SUNDAY MOVING FARTHER OFFSHORE AS NEXT FRONT
APPROACHES LATE MONDAY INTO TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1125 PM TUESDAY...TRENDS FROM THE LATEST KLTX AND SURROUNDING
88-DS INDICATE THE PCPN ACTIVITY REMAINS WEST THRU NORTHWEST OF THE
ILM CWA. THE ACTIVITY CONTINUES TO DISSIPATE AS IT APPROACHES THE
ILM CWA. HRRR/RUC MODELS INDICATE THE LACK OF INSTABILITY IE.
CAPE...AS THE MAJOR REASON FOR THE LACK OF PCPN DEVELOPMENT ACROSS
THE ILM CWA LATE THIS EVENING. HAVE TRIMMED POPS FOR THE REMAINDER
OF THE OVERNIGHT. LATEST HRRR INDICATES LOW CAPE VALUES TOWARD
DAYBREAK WEDNESDAY. HOWEVER MODELS INDICATE SUBSIDENCE ALOFT
DURING THE PRE-DAWN WED HOURS WHICH WILL LIMIT TSRA PRODUCTION AND
COVERAGE ACROSS THE ILM CWA. AS FOR POPS...WILL BASICALLY ADVERTISE
NO CHANCE FOR THE IMMEDIATE COAST AND LOW CHANCE MAINLY WEST OF I-95
TOWARD DAYBREAK WED. HAVE LEANED WITH NAM MOS GUIDANCE FOR MIN
TEMPS TONIGHT...WITH SOME MINOR TWEAKS EITHER UPWARDS ALONG THE
IMMEDIATE COAST OR LOWER...LOW TO MID 60S...ACROSS AREAS OBSERVING
MOSTLY CLEAR SKIES. SSTS IN THE 70S COMBINED WITH ONSHORE FLOW WILL
LIKELY KEEP THE IMMEDIATE COASTAL COUNTY ZONES NEAR 70.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/...
AS OF 245 PM TUESDAY...MAIN FORECAST CHALLENGE IS THE POTENTIAL FOR
SEVERE WEATHER WITH A COLD FRONT MOVING THROUGH THE AREA WEDNESDAY
AND WEDNESDAY NIGHT. AMPLE CLOUD COVER AHEAD OF THE FRONT WILL
IMPACT THE INSTABILITY...HOWEVER RRQ OF AN H3 JET WILL ADD LIFT TO
THE REGION RESULTING IN DECENT CONVECTIVE COVERAGE. IN THE END...MAY
NEED TO DEAL WITH A FEW SEVERE TSTMS WITH DAMAGING WINDS AS THE
PRIMARY THREAT. SPC CONTINUES TO HIGHLIGHT NEARLY THE ENTIRE ILM
FORECAST AREA IN A SLIGHT RISK.
ONCE THE FRONT MOVES THROUGH MUCH DRIER CONDITIONS WILL PREVAIL WITH
NEAR SEASONABLE TEMPERATURES ON TAP. PRECIPITABLE WATER VALUES OF
1.7 INCHES WEDNESDAY AFTERNOON/EVE WILL DROP BELOW 0.75 INCHES
THURSDAY. TIME HEIGHT CROSS SECTIONS INDICATE A VERY DRY COLUMN
ABOVE H8 WHICH WILL LEAD TO MOSTLY SUNNY SKIES BY THURSDAY MORNING.
HIGHS ON THURSDAY WILL BE AROUND 80 MOST LOCATIONS AND LOWS WILL BE
A COUPLE CATEGORIES BELOW NORMAL THURSDAY NIGHT (LOWER 50S PEE DEE
AND LBT AREAS TO THE MID 50S INLAND COASTAL AREAS). LASTLY...UNTIL
THE LOW-LEVEL WIND FIELD WEAKENS COULD SEE 20-25 MPH GUSTS IN
NORTHWEST FLOW THURSDAY MORNING.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 245 PM TUESDAY...PERIOD STARTS OFF DRY WITH TEMPERATURES NEAR
TO SLIGHTLY CLIMO AS 5H TROUGH AXIS MOVES OFF THE COAST AND SURFACE
HIGH SETTLES IN FROM THE NORTH. COMBINATION OF SURFACE HIGH AND WEAK
5H RIDGE AXIS OVER THE WEEKEND SHOULD KEEP THE AREA DRY FOR MUCH OF
THE WEEKEND. LATE SUN AFTERNOON RETURN FLOW AROUND EXITING HIGH AND
DEEPER SOUTHWEST FLOW ON THE WEST SIDE OF EXITING RIDGE ALOFT MAY
LEAD TO SOME CONVECTION ACROSS WESTERN AREAS. WILL CARRY SILENT POP
FOR SUN AFTERNOON AT THIS POINT. PRECIP CHANCES INCREASE DURING THE
MON/TUE TIMEFRAME. MEDIUM RANGE GUIDANCE IS SHOWING BROAD 5H TROUGH
DEVELOPING OVER THE EASTERN US NEXT WEEK...THOUGH MANY OF THE
PARTICULARS REMAIN IN QUESTION. IT DOES APPEAR THERE WILL BE PLENTY
OF MOISTURE IN THE AREA...GIVEN THE DEEP SOUTHWEST FLOW. SETUP MON
LOOK FAVORABLE AS FAR AS DIURNAL CONVECTION IS CONCERNED. TUE LOOKS
A LITTLE MORE SYNOPTIC WITH A WEAK COASTAL TROUGH OR WARM FRONT IN
THE VICINITY AND LOW PRESSURE MOVING UP THE COAST. AT THIS POINT
WILL CONTINUE WITH SLIGHT CHANCE MON/MON NIGHT INCREASING TO LOW
CHANCE FOR TUE/TUE NIGHT. TEMPERATURES WILL REMAIN NEAR TO SLIGHTLY
BELOW CLIMO THROUGH THE PERIOD.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 06Z...PRECIPITATION STILL LOOMING OFF TO THE WEST OF LBT AND
FLO WITH CLOUD DECK SLOWLY SPREADING TO THE EAST. MODELS STILL IN
PRETTY GOOD AGREEMENT WITH HOLDING OFF ANY PRECIPITATION ACROSS
THE TERMINALS FOR THE REST OF THE OVERNIGHT PERIOD BEFORE BRINGING
THE SHOWERS AND STORMS AHEAD OF THE COLD FRONT ON WEDNESDAY
AFTERNOON INTO THE EVENING. FROM PREVIOUS DISCUSSION...LOW LEVEL
MOISTURE WILL CONTINUE TO BE ON THE INCREASE TONIGHT ON SOUTH
WINDS COURTESY OF THE HIGH OFF THE COAST. WILL BE A BIT MORE
OPTIMISTIC FOR THE OVERNIGHT PERIOD AND KEEP TERMINALS VFR THROUGH
08Z-09Z ACROSS THE INLAND TERMINALS WHERE SOME PATCHY FOG IS
FORECAST TO DEVELOP. HAVE KEPT CATEGORICAL PRECIPITATION OUT OF
THE TERMINALS ON WEDNESDAY AND JUST WENT WITH VICINITY FORECAST
THROUGH 20Z-21Z BEFORE GOING WITH TEMPO GROUP. CLIMO HAS SHOWN
THAT THE PROBABILITY OF SHOWERS OR THUNDERSTORMS TO BE OVER A
PARTICULAR TERMINAL DURING THE AFTERNOON TO BE RATHER LOW SO WILL
FORECAST VFR FOR THE TERMINALS THROUGH LATE AFTERNOON.
EXTENDED OUTLOOK...MODERATE CONFIDENCE FOR SCATTERED TO POSSIBLE
NUMEROUS SHOWERS AND THUNDERSTORMS WEDNESDAY AFTERNOON THROUGH
WEDNESDAY NIGHT...WITH INTERMITTENT IFR POSSIBLE. BECOMING VFR
THURSDAY AND CONTINUING THROUGH SUNDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1125 PM TUESDAY...SE-S WINDS TO START THE EVENING...AND WILL
SLIGHTLY VEER TO THE S-SSW OVERNIGHT. SPEEDS TO REMAIN AROUND 10 KT.
THE LOW SPEEDS CAN BE CONTRIBUTED TO A WEAK/RELAXED SFC PG...WHICH
WILL REMAIN ACROSS THE WATERS DURING THE REMAINING OVERNIGHT PERIOD.
SIGNIFICANT SEAS WILL RANGE BETWEEN 2 AND 4 FT...WITH THE 4 FOOTERS
PRIMARILY ACROSS THE WATERS FROM CAPE FEAR NORTHWARD. THE MAJOR
CONTRIBUTOR FOR THE SIG. SEAS AS ILLUSTRATED BY WAVEWATCH3 WILL COME
FROM A 3 TO 5 FT NE SWELL EXHIBITING 10-11 SECOND PERIODS JUST
OFFSHORE AND BEYOND THE SHOALS. FOR THE COASTAL WATERS...THE SWELL
DIRECTION WILL VEER TO THE ENE AND DROP TO 2 TO 3 FT DUE TO WAVE
REFRACTION ACROSS THE SHALLOW SHOALS OFF CAPE LOOKOUT AND OFF CAPE
FEAR. ADD THE 1 FT SHORT PERIOD LOCAL WIND WAVE...AND SIG SEAS EQUAL
TO 2 TO 4 FT.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 245 PM TUESDAY...SOUTHERLY WINDS WEDNESDAY AHEAD OF THE COLD
FRONT WILL VEER TO A WEST-NORTHWEST DIRECTION IN ITS WAKE WEDNESDAY
NIGHT. ADDITIONAL VEERING TO A NORTHERLY DIRECTION EXPECTED THURSDAY
AS HIGH PRESSURE BUILDS ACROSS THE WATERS. SPEEDS WILL INCREASE
10-15 KTS AHEAD OF THE FRONT THEN PEAK AROUND 15 KNOTS IN ITS WAKE.
COULD SEE A MINOR SURGE ARRIVE OVER THE WATERS LATE THURSDAY WITH
SPEEDS PICKING UP OVER THE WATERS AWAY FROM THE COAST. SEAS WILL
RANGE FROM 2-3 FT ACROSS LONG BAY AND 2-4 FT ACROSS ONSLOW BAY
WEDNESDAY...THEN NEARLY A SOLID 4 FT OFF CAPE FEAR AND 3 FT OVER
LONG BAY WED NIGHT. SEAS WILL BE AROUND 3 FT THURSDAY THEN SLIGHTLY
INCREASE AWAY FROM THE COAST LATE THURSDAY NIGHT WITH THE
AFOREMENTIONED MINOR SURGE. OTHERWISE...SCATTERED TO NUMEROUS
SHOWERS AND TSTMS WILL LOCALLY ENHANCE WINDS...ESPECIALLY WEDNESDAY
NIGHT.
LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 245 PM TUESDAY...NORTHERLY FLOW AT THE START OF THE PERIOD
WILL BE DECREASING AND VEER TO NORTHEAST THROUGHOUT THE DAY AS
SURFACE HIGH SETTLES SOUTH. RELAXED GRADIENT WILL SEE SPEEDS DROP TO
10 KT OR LESS BY AFTERNOON. WEAK SEA BREEZE DEVELOPS IN THE
AFTERNOON...BUT COOLER NORTHEAST FLOW WILL HELP LIMIT THE STRENGTH
OF THE NEAR SHORE CIRCULATION. LIGHT NORTHEAST FLOW CONTINUE TO VEER
FRI NIGHT INTO SAT AS CENTER OF THE HIGH MOVES OFF THE COAST JUST
NORTH OF THE WATERS. EAST TO SOUTHEAST FLOW AROUND 10 KT SAT BECOMES
SOUTHEAST SAT NIGHT AND SUN. SPEEDS START TO PICK UP SUN INTO SUN
NIGHT AS GRADIENT BECOMES A LITTLE MORE DEFINED. WINDS UNDER 15 KT
THROUGH THE PERIOD WILL KEEP SEAS 2 TO 3 FT.
&&
.TIDES/COASTAL FLOODING...
AS OF 1125 PM TUESDAY...HAVE EXTENDED THE ATLANTIC WATERFRONT MINOR
COASTAL FLOOD THREAT TO 1 AM WED. THIS A RESULT OF THE LATEST
OBSERVED TIDE READINGS CONTINUING WITHIN THRESHOLDS...EVEN THOUGH
THE OCCURRENCE OF HIGH TIDE HAS OCCURRED. THE ET SURGE MODEL
APPEARED TO DO QUITE WELL WITH TODAYS MIDDAY HIGH TIDE...THE LOWER
OF THE 2 PER DAY. WITH THAT SAID...THE ET MODEL STILL BRINGS EAST
FACING BEACHES AND CAPE FEAR RIVER TO THE VERY CUSP OF MINOR
FLOOD...WHICH IS TYPICALLY QUITE COMMON. SOME FLOODING THRESHOLDS
UNCERTAINTY FOR BRUNSWICK COUNTY BEACHES WITH THE TIDE GAGE NOT
WORKING...BUT THERE WERE SEVERAL REPORTS TODAY OF FLOODING AT OCEAN
ISLE BEACH. AS A RESULT...HAVE CONTINUED TO INCLUDE IN THE ADVISORY
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY UNTIL 3 AM EDT EARLY THIS MORNING FOR
NCZ107.
MARINE...NONE.
&&
$$
AVIATION...MAC
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
601 AM EDT WED MAY 9 2012
.SYNOPSIS...
AN UPPER LEVEL TROUGH EXTENDING FROM THE GREAT LAKES SOUTHWARD
THROUGH THE MID MISSISSIPPI VALLEY WILL AMPLIFY AND PROGRESS
EASTWARD TODAY...REACHING THE CENTRAL APPALACHIANS BY TONIGHT. THE
COLD FRONT OVER THE MID-ATLANTIC PIEDMONT WILL BECOME NEARLY
STATIONARY ALONG THE COASTAL PLAIN AS A SECONDARY WAVE OF LOW
PRESSURE DEVELOPS AND LIFTS NORTHWARD ALONG THE BOUNDARY. THE
FRONT WILL EVENTUALLY SHIFT OFFSHORE EARLY THURSDAY LEAVING BEHIND
A COOL AND GUSTY NORTHWEST FLOW. FAIR AND DRY WEATHER IS IN STORE
FOR FRIDAY THROUGH THE FIRST HALF OF THE UPCOMING WEEKEND WITH
HIGH PRESSURE RETURNING TO THE AREA.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
08Z RUC SFC ANALYSIS SHOWS LOW PRES CENTERED JUST NORTH OF OTTAWA
CANADA WITH COLD FRONT/SFC TROF EXTENDING SWD INTO ERN PA. RADAR
SHOWS LGT RAINS LIFTING NEWD ACRS THE CHESAPEAKE BAY AND CLIPPING
FAR SE PA. THIS ACTIVITY IS ASSOCD WITH A WEAK MID LVL S/W
EMBEDDED WITHIN THE LEADING EDGE OF MAIN UPPER TROF MOVG EWD ACRS
THE MIDWEST/CENTRAL GREAT LAKES. NOT EXPECTING ANY PCPN THRU MID
MORNING...WITH PATCHY FOG AND LOW CLOUDS DISSIPATING SHORTLY AFTER
SUNRISE.
THE UPPER TROF WILL AMPLIFY AS IT SHIFTS EWD INTO THE ERN GREAT
LAKES/UPPER OHIO VALLEY BY THIS EVE. COMBO OF LG SCALE LIFT AND
COOLING ALOFT/STEEPENING LAPSE RATES ASSOCD WITH THE APPROACHING
UPPER TROF WILL TRIGGER ISOLD-SCT SHOWERS OVR THE WRN ALLEGHENIES
DURING LATE MORNING/EARLY AFTN...WITH SIMILAR CVRG SPREADING EWD
INTO THE CENTRAL MTNS MID BY PEAK HEATING. ALTHOUGH INSTABILITY
WILL BE LIMITED...CAN/T RULE OUT A RUMBLE OF TS IN OVR THE NW MTNS
WHERE 850-500MB LAPSE RATES NEAR 7 C/KM BY LATE IN THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
HEIGHT FALLS CROSSING THE CENTRAL APPLCHNS WILL INDUCE A SECONDARY
WAVE OF LOW PRES WHICH WILL LIFT NWD ALONG THE SLOW-MOVG BNDRY OVER
THE MID-ATLC PIEDMONT/COASTAL PLAIN. MDLS AGREE THAT THE FAR ERN
ZONES WILL BE ON THE WRN EDGE OF MOD-LCLY HVY PCPN AXIS EXPECTED
ALONG THE MID-ATLC COAST AS THE SFC WAVE INTERACTS WITH RICH PLUME
OF DEEP MSTR/HI PWATS.
THE PATTERN EVENTUALLY EVOLVES TWD A TYPICAL COLD SEASON CYC/NWLY
FLOW REGIME...WITH DEEPENING SFC LOW LIFTING NWD ALONG THE SRN NEW
ENGLAND COAST. WNW WINDS WILL INCREASE ON THE BACKSIDE OF THE
DEPARTING SYS.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
MODELS ARE CONSISTENT THROUGH FRIDAY...AS THE EC TAKES A STRONG
UPPER LEVEL EAST...AND THE GFS MOVES THE SYSTEM NORTH...WITH A
SLIGHT RETROGRADE. A SHARP UPPER LEVEL RIDGE AND ASSOCIATED
1026-1029 MB SC HIGH BUILDS INTO THE REGION FRIDAY NIGHT INTO
SATURDAY. THE RIDGE CONTINUES TO TREND WEAKER AS IT SHOULD BE
FLATTENING OUT BY SATURDAY NIGHT AS SHORTWAVE ENERGY STREAKS SE
ACROSS THE UPPER GREAT LAKES. GUIDANCE DISAGREES ON THE TIMING OF
THIS SHORTWAVE...THE OPERATIONAL EC BRINGING IT THROUGH FASTER
THAN THE GFS.
DUE TO THE HIGH PRESSURE TEMPS SHOULD WARM BACK TOWARD NORMAL
WITH BELOW NORMAL CHANCES OF PCPN OCCURRING FRIDAY THROUGH SUNDAY.
THE NEXT CHC FOR ANY RAIN SHOWERS WILL COME LATE SUNDAY AFTERNOON
AND...DEPENDING ON THE PROGRESSION OF THE COLD FRONT HEADED ESE
FROM THE GREAT LAKES...WILL CONTINUE THROUGH SUNDAY NIGHT INTO
MONDAY MORNING.
&&
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
LOW CIGS AND FOG ARE IMPROVING AS OF 10Z ACRS THE WESTERN TAF
SITES AND EXPECT THIS TREND TO CONTINUE. AREAS OF FOG AND STRATUS
ARE STILL IMPACTING THE ERN TAFS BUT ALSO ANTICIPATING IMPROVING
CONDS HERE WITHIN THE NEXT FEW HOURS.
SCT -SHRA WILL BE PSBL FM LATE MORNING THRU THE AFTN OVR WRN AND
CENTRAL TERMINALS...AS THE AIR COOLS ALOFT AND FORCING INCREASES
AHEAD OF THE UPPER TROUGH APPROACHING FROM THE WEST. CVRG IS XPTD
TO BE SCT AT BEST AND MAY REMOVE VCSH WITH THE 12Z TAF SET. THE
OVERALL PATTERN WILL EVENTUALLY TRANSITION TO A COOL NWLY POST-
FRONTAL REGIME AS THE UPPER TROUGH CROSSES THE NE STATES AND LOW
PRES DEEPENS AS IT LIFTS NWD ALONG THE SRN NEW ENG COAST.
OUTLOOK...
THU...MVFR NORTH/WEST. VFR SOUTH/EAST. GUSTY NW WINDS.
FRI-SUN...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...LAMBERT/GARTNER
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
538 AM EDT WED MAY 9 2012
.SYNOPSIS...
AN UPPER LEVEL TROUGH EXTENDING FROM THE GREAT LAKES SOUTHWARD
THROUGH THE MID MISSISSIPPI VALLEY WILL AMPLIFY AND PROGRESS
EASTWARD TODAY...REACHING THE CENTRAL APPALACHIANS BY TONIGHT. THE
COLD FRONT OVER THE MID-ATLANTIC PIEDMONT WILL BECOME NEARLY
STATIONARY ALONG THE COASTAL PLAIN AS A SECONDARY WAVE OF LOW
PRESSURE DEVELOPS AND LIFTS NORTHWARD ALONG THE BOUNDARY. THE
FRONT WILL EVENTUALLY SHIFT OFFSHORE EARLY THURSDAY LEAVING BEHIND
A COOL AND GUSTY NORTHWEST FLOW. FAIR AND DRY WEATHER IS IN STORE
FOR FRIDAY THROUGH THE FIRST HALF OF THE UPCOMING WEEKEND WITH
HIGH PRESSURE RETURNING TO THE AREA.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
08Z RUC SFC ANALYSIS SHOWS LOW PRES CENTERED JUST NORTH OF OTTAWA
CANADA WITH COLD FRONT/SFC TROF EXTENDING SWD INTO ERN PA. RADAR
SHOWS LGT RAINS LIFTING NEWD ACRS THE CHESAPEAKE BAY AND CLIPPING
FAR SE PA. THIS ACTIVITY IS ASSOCD WITH A WEAK MID LVL S/W
EMBEDDED WITHIN THE LEADING EDGE OF MAIN UPPER TROF MOVG EWD ACRS
THE MIDWEST/CENTRAL GREAT LAKES. NOT EXPECTING ANY PCPN THRU MID
MORNING...WITH PATCHY FOG AND LOW CLOUDS DISSIPATING SHORTLY AFTER
SUNRISE.
THE UPPER TROF WILL AMPLIFY AS IT SHIFTS EWD INTO THE ERN GREAT
LAKES/UPPER OHIO VALLEY BY THIS EVE. COMBO OF LG SCALE LIFT AND
COOLING ALOFT/STEEPENING LAPSE RATES ASSOCD WITH THE APPROACHING
UPPER TROF WILL TRIGGER ISOLD-SCT SHOWERS OVR THE WRN ALLEGHENIES
DURING LATE MORNING/EARLY AFTN...WITH SIMILAR CVRG SPREADING EWD
INTO THE CENTRAL MTNS MID BY PEAK HEATING. ALTHOUGH INSTABILITY
WILL BE LIMITED...CAN/T RULE OUT A RUMBLE OF TS IN OVR THE NW MTNS
WHERE 850-500MB LAPSE RATES NEAR 7 C/KM BY LATE IN THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
HEIGHT FALLS CROSSING THE CENTRAL APPLCHNS WILL INDUCE A SECONDARY
WAVE OF LOW PRES WHICH WILL LIFT NWD ALONG THE SLOW-MOVG BNDRY OVER
THE MID-ATLC PIEDMONT/COASTAL PLAIN. MDLS AGREE THAT THE FAR ERN
ZONES WILL BE ON THE WRN EDGE OF MOD-LCLY HVY PCPN AXIS EXPECTED
ALONG THE MID-ATLC COAST AS THE SFC WAVE INTERACTS WITH RICH PLUME
OF DEEP MSTR/HI PWATS.
THE PATTERN EVENTUALLY EVOLVES TWD A TYPICAL COLD SEASON CYC/NWLY
FLOW REGIME...WITH DEEPENING SFC LOW LIFTING NWD ALONG THE SRN NEW
ENGLAND COAST. WNW WINDS WILL INCREASE ON THE BACKSIDE OF THE
DEPARTING SYS.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
MODELS ARE CONSISTENT THROUGH FRIDAY...AS THE EC TAKES A STRONG
UPPER LEVEL EAST...AND THE GFS MOVES THE SYSTEM NORTH...WITH A
SLIGHT RETROGRADE. A SHARP UPPER LEVEL RIDGE AND ASSOCIATED
1026-1029 MB SC HIGH BUILDS INTO THE REGION FRIDAY NIGHT INTO
SATURDAY. THE RIDGE CONTINUES TO TREND WEAKER AS IT SHOULD BE
FLATTENING OUT BY SATURDAY NIGHT AS SHORTWAVE ENERGY STREAKS SE
ACROSS THE UPPER GREAT LAKES. GUIDANCE DISAGREES ON THE TIMING OF
THIS SHORTWAVE...THE OPERATIONAL EC BRINGING IT THROUGH FASTER
THAN THE GFS.
DUE TO THE HIGH PRESSURE TEMPS SHOULD WARM BACK TOWARD NORMAL
WITH BELOW NORMAL CHANCES OF PCPN OCCURRING FRIDAY THROUGH SUNDAY.
THE NEXT CHC FOR ANY RAIN SHOWERS WILL COME LATE SUNDAY AFTERNOON
AND...DEPENDING ON THE PROGRESSION OF THE COLD FRONT HEADED ESE
FROM THE GREAT LAKES...WILL CONTINUE THROUGH SUNDAY NIGHT INTO
MONDAY MORNING.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
LGT W/SW WNDS COMBINED WITH PARTIAL CLEARING AND HIGH LLVL/BLYR MSTR
IS RESULTING IN POCKETS OF IFR/MVFR STRATUS AND FOG EARLY THIS
MORNING IN WAKE OF COLD FNT SHIFTING EWD INTO ERN PA. XPT CONDS
TO IMPROVE TO MVFR AND VFR BY MID MORNING. THE COLD FRONT WILL
BECOME NEARLY STATIONARY OVR ERN PA/NJ AND DELMARVA AS A WELL-
DEFINED UPPER LEVEL TROUGH SHIFTS SEWD FM THE GRT LKS. SCT -SHRA
WILL BE PSBL FM LATE MORNING THRU THE AFT AS THE AIR COOLS ALOFT
AND FORCING INCREASES AHEAD OF THE UPPER TROUGH AXIS. THE OVERALL
PATTERN WILL EVENTUALLY TRANSITION TO A MORE OF A COLD SEASON NWLY
POST-FRONTAL REGIME AS THE UPPER TROUGH CROSSES THE NE STATES AND
LOW PRES DEEPENS NWD ALONG THE NEW ENG COAST.
OUTLOOK...
THU...MVFR NORTH/WEST. VFR SOUTH/EAST.
FRI-SUN...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...LAMBERT/GARTNER
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
344 AM CDT WED MAY 9 2012
.SHORT TERM...TODAY THROUGH FRIDAY
343 AM CDT WED MAY 9 2012
AT 3 AM...A TROUGH OF LOW PRESSURE WAS LOCATED JUST NORTH OF THE
INTERSTATE 90 CORRIDOR. THERE ARE A FEW SHOWERS STILL BEING
DETECTED BY RADAR JUST BEHIND THE TROUGH AXIS. NOT OVERLY
SURPRISED BY THIS...BECAUSE THE SAME THING WAS HAPPENING ACROSS
NORTHERN MINNESOTA ON TUESDAY MORNING. THE HRRR SUGGESTS THAT
THESE SHOWERS WILL DISSIPATE BY 09.12Z...SO KEPT THE FORECAST DRY
ACROSS THE AREA TODAY.
FOR TONIGHT AND EARLY THURSDAY MORNING...THE 09.00Z MODELS ARE IN
VERY GOOD AGREEMENT THAT THE 500 MB POTENTIAL VORTICITY ANOMALY
/CURRENTLY LOCATED OVER MONTANA/ WILL MOVE THROUGH THE FORECAST
AREA. THIS HAS BEEN A CONSISTENT SIGNAL OVER THE PAST COUPLE OF
DAYS. WITH MUCH OF THE MOISTURE ASSOCIATED WITH THIS SYSTEM IS
LOCATED ABOVE ABOVE 600 MB...ONLY EXPECTING A BROKEN DECK OF MID
AND HIGH CLOUDS. THESE CLOUDS WILL LIKELY LIMIT SOME OF NOCTURNAL
COOLING...SO RAISED THE TEMPERATURES BY A FEW DEGREES.
ON FRIDAY...ALL OF THE 09.00Z MODELS ARE IN VERY GOOD AGREEMENT
THAT A CANADIAN COLD FRONT WILL MOVE SOUTHEAST ACROSS
MINNESOTA...WESTERN IOWA...AND NORTHERN WISCONSIN. THIS FRONT WILL
HAVE LIMITED MOISTURE TO WORK DUE TO THE UPPER LEVEL LOW OVER TEXAS
PREVENTING THIS SYSTEM FROM TAPPING INTO GULF OF MEXICO MOISTURE.
WHILE THIS WILL BE CASE...MEAN LAYER CAPES STILL CLIMB INTO THE
500 TO 1000 J/KG RANGE AHEAD OF THIS FRONT. BUFKIT SOUNDINGS SHOW
THAT THERE WILL BE A CAP LOCATED BETWEEN 750 AND 650 MB. AS HAS
BEEN THE CASE OVER THE PAST SEVERAL DAYS...THE ECMWF CONTINUES TO
KEEP THE PRECIPITATION JUST WEST OF THE FORECAST AREA. MEANWHILE
THE GFS AND NAM/WRF HAVE COME AROUND TO GEM SOLUTION OF GENERATING
PRECIPITATION ACROSS THE ENTIRE AREA DURING THE AFTERNOON. THE
MAIN DIFFERENCE IS HOW FAST THE CAP ERODES. DUE TO THIS
UNCERTAINTY...JUST KEPT THE PRECIPITATION PROBABILITIES BETWEEN
25 AND 34 PERCENT. WITH WEAK 0-3 KM AND 0-6 KM SHEAR...IT STILL
DOES NOT LOOK LIKE THAT ANY OF THESE THUNDERSTORMS WOULD BECOME
SEVERE.
.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
343 AM CDT WED MAY 9 2012
ON FRIDAY NIGHT...ALL OF THE 09.00Z MODELS ARE IN FAIRLY GOOD
AGREEMENT THAT A COLD FRONT WILL MOVE SOUTHEAST THROUGH NORTHEAST
IOWA...AND SOUTHWEST AND CENTRAL WISCONSIN. THE INSTABILITY
GRADUALLY WANES DURING THE EVENING...THEREFORE...CONFINED THE
PRECIPITATION CHANCES TO MAINLY THE EVENING.
ON TUESDAY...THE LAST TWO RUNS OF THE ECMWF AND 09.00Z GFS
INDICATE THAT A WEAK SHORT WAVE TROUGH WILL MOVE SOUTHEAST ACROSS
NORTHERN MINNESOTA...NORTHERN WISCONSIN...AND SOUTHWEST ONTARIO.
OVERALL THE BEST FORCING WILL BE LOCATED TO THE NORTH AND EAST OF
THE FORECAST AREA. HOWEVER THE MEAN LAYER CAPES WILL RANGE FROM
500 TO 1000 J/JG...THIS WILL BE ENOUGH INSTABILITY FOR THE
POSSIBILITY OF SOME SCATTERED SHOWERS. THE 09.00Z GFS AND 08.12Z
ECMWF SUGGEST THAT THESE SHOWERS WOULD BE MAINLY NORTH OF
WISCONSIN 29. MEANWHILE THE 09.00Z ECMWF HAS THESE SHOWERS ACROSS
THE ENTIRE AREA. WITH THE BEST CONSISTENCY ACROSS TAYLOR AND
NORTHERN CLARK COUNTIES IN NORTH CENTRAL WISCONSIN...WENT WITH A
15 TO 24 PERCENT PRECIPITATION PROBABILITY AND LEFT THE REMAINDER
OF THE AREA DRY FOR NOW.
&&
.AVIATION...THROUGH 06Z THURSDAY
1136 PM CDT TUE MAY 8 2012
AN AREA OF HIGH PRESSURE OVER THE DAKOTAS WILL SLOWLY BUILD EAST
INTO THE TAF SITES BY THIS EVENING. DRIER AIR FILTERING IN ON
NORTH TO NORTHWEST WINDS IN THE LOW LEVELS IS EXPECTED TO MAINTAIN
VFR CONDITIONS THROUGHOUT. SHOULD HAVE PERIODS OF BROKEN VFR
CUMULUS THROUGH WEDNESDAY...WHICH COMBINED WITH A GENERAL 5 TO 10
KT BREEZE WILL LIKELY PREVENT ANY FOG FROM FORMING THIS MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
241 AM CDT WED MAY 9 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS DENVER CO
944 AM MDT WED MAY 9 2012
.UPDATE...CURRENT FORECASTS ON TRACK. STILL A SLIGHT CHANCE FOR
THUNDERSTORMS ACROSS THE MOUNTAINS SOUTH OF INTERSTATE 70 THIS
AFTERNOON OR EARLY EVENING WHERE RUC SHOWS SOME MOISTURE BUT
LIMITED INSTABILITY. IF STORMS DEVELOP...THERE WILL BE MORE WIND
THAN RAIN. OTHERWISE DRY AND WARMER.
&&
.AVIATION...CURRENT TAF TRENDS LOOK GOOD AND WILL CONTINUE FOR THE
18Z ISSUANCE.
&&
.PREV DISCUSSION... /ISSUED 410 AM MDT WED MAY 9 2012/
SHORT TERM...WK WNW FLOW ALOFT WILL BE OVER THE AREA THRU TONIGHT
WITH LITTLE MOISTURE. COULD STILL SEE AN ISOLATED WK TSTM OR TWO
OVER THE MTNS SOUTH OF I-70 BY LATE AFTN OR EARLY EVENING SO WILL
KEEP IN VERY LOW POPS FOR THIS AREA. OTHERWISE IT WILL REMAIN DRY
ELSEWHERE. HIGHS THIS AFTN BASED ON DECENT 850-700 MB WARMING
SHOULD RISE INTO THE 75 TO 80 DEGREE RANGE OVER NERN CO.
LONG TERM...MODELS KEEP AN UPPER RIDGE OVER THE FORECAST AREA ON
THURSDAY INTO THURSDAY EVENING. THEY HAVE AN UPPER TROUGH MOVING
EASTWARD TO THE NORTH OF COLORADO THURSDAY NIGHT INTO FRIDAY. THE
FLOW ALOFT IS FAIRLY WEAK AND WEST-SOUTHWESTERLY OVER THE CWA THE
REST OF THE THURSDAY NIGHT THROUGH FRIDAY NIGHT. A FAIRLY STRONG
COLD FRONT IT PROGGED TO MOVE INTO THE CWA THURSDAY NIGHT. THERE IS
WEAK UPWARD SYNOPTIC SCALE ENERGY PROGGED OVER THE CWA FROM THURSDAY
AFTERNOON THROUGH FRIDAY NIGHT. SOUTHEAST TO SOUTHERLY BOUNDARY
LAYER WINDS ARE PROGGED FOR THE CWA THURSDAY INTO THURSDAY EVENING.
AFTER MIDNIGHT THURSDAY NIGHT...MODELS HAVE A DECENT COLD FRONT MOVE
SOUTH OVER THE CWA...WITH NORTHEASTERLY UPSLOPE FLOW BEHIND IT
THROUGH FRIDAY. BY FRIDAY NIGHT...EAST-SOUTHEASTERLY UPSLOPE IS
PROGGED. FOR MOISTURE...THERE IS LITTLE THURSDAY MORNING...THEN A
BIT BY LATE DAY AND EVENING ASSOCIATED WITH CONVECTION. BY 12Z
FRIDAY MORNING...LOW LEVEL MOISTURE IS OVER THE PLAINS AND FOOTHILLS
WITH THE UPSLOPE FLOW. MOISTURE INCREASES ON FRIDAY...AND IT IS
PRETTY DEEP OVER MUCH OF THE CWA BY LATE AFTERNOON. THIS MOISTURE
CONTINUES FRIDAY NIGHT. BOUNDARY LAYER DEW POINT READINGS ARE
PROGGED FROM THE TEENS F WEST TO AROUND 30 F EAST LATE DAY
THURSDAY. AFTER THE FRONT...DEW POINTS ARE MAINLY IN THE 30S F FOR
FRIDAY AND FRIDAY NIGHT...HOWEVER THE MOUNTAINS ARE A BIT DRIER
UNTIL FRIDAY NIGHT. THERE IS SOME MINOR CAPE PROGGED OVER THE
FORECAST AREA LATE DAY THURSDAY. THERE IS BETTER CAPE OVER THE
MOUNTAINS...FROM THE DIVIDE WEST FOR FRIDAY. THE PLAINS ARE TOO
STABLE. THE QPF FIELDS SHOW A TAD OF MEASURABLE PRECIPITATION OVER
THE MOUNTAINS...FOOTHILLS AND ADJACENT PLAINS LATE DAY AND EVENING
THURSDAY. THERE IS A TAD INDICATED FRIDAY AND FRIDAY NIGHT OVER ALL
AREAS. WILL GO WITH SOME MINOR POPS OVER THE MOUNTAINS LATE DAY
THURSDAY. WITH THE PREVIOUS STORM IN MIND...WILL GO WITH 20-50%
POPS FRIDAY AND FRIDAY NIGHT. HIGHEST OVER THE TERRAIN FROM THE
DIVIDE EAST. WILL ONLY MENTION "SLIGHT CHANCES" FOR THUNDER IN THE
MOUNTAINS. FOR TEMPERATURES...THURSDAY`S HIGHS ARE 2-3 C WARMER
THAN TODAY`S. FRIDAY`S COOL OFF SIGNIFICANTLY BY 10-17 C. FOR THE
LATER DAYS...SATURDAY THROUGH TUESDAY...WEAK UPPER TROUGHINESS IS
AROUND SATURDAY INTO SUNDAY...THEN WEAK UPPER RIDGING MOVES IN
THROUGH TUESDAY...LEAVING THE CWA IN NORTHWESTERLY FLOW ALOFT.
MOISTURE IS STILL AROUND SATURDAY...BUT DECREASES SATURDAY NIGHT...
WITH SPARSE MOISTURE AROUND THROUGH TUESDAY. TEMPERATURES STAY
PRETTY COOL SATURDAY...BUT WARM-UP SOMEWHAT SUNDAY THROUGH TUESDAY.
AVIATION...VFR THRU TONIGHT. SLY DRAINAGE WINDS EARLY THIS MORNING
WILL BECOME LIGHT SWLY BY 15Z AND THEN LIGHT NELY AFTER 18Z. BY
THIS EVENING WINDS WILL BECOME DRAINAGE AGAIN AFTER 02Z.
HYDROLOGY...NO TSTMS ARE EXPECTED IN THE BURN AREAS TODAY OR TONIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....RJK
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1017 AM EDT WED MAY 9 2012
.SYNOPSIS...
A COLD FRONT SLOWLY CROSSES THE REGION TODAY...THEN MOVES OFF THE
COAST TONIGHT. HIGH PRESSURE BUILDS INTO THE AREA THURSDAY THROUGH
THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
INITIAL FRONT ALMOST STALLED NORTHEAST TO SOUTHWEST ACROSS CENTRAL
VIRGINIA. THE MODELS ARE DEPICTING THIS MOVING ONLY SLOWLY EAST
WHILE A STRONGER FRONT IN THE OHIO VALLEY CATCHES UP WITH IT THIS
EVENING. HAVE ONE AREA OF PRECIPITATION ALONG THE INITIAL FRONT.
THESE SHOWERS WILL SLOWLY DIMINISH INTO EARLY AFTERNOON. FARTHER
WEST CAN SEE MORE SHOWERS DEVELOPING AND ENHANCING IR IMAGE. THIS
CORRESPONDS TO INCREASING DIVERGENCE FROM THE JET. MODELS MOVE
THIS AREA INTO MUCH OF THE COUNTY WARNING AREA DURING THE
AFTERNOON AND EVENING. ALSO WITH STRONG POTENTIAL VORTICITY MAX
MOVING OVER THE AREA THIS EVENING WILL ENHANCE THE LIFT AS WELL.
SO PLENTY OF RAIN AND SOME OF IT WILL BE QUITE HEAVY AS
PRECIPITABLE WATER OVER 180 PERCENT OF NORMAL.
PLENTY OF QUESTION ON THUNDERSTORMS AND IF ANY WILL BE SEVERE. DO
HAVE A FEW BREAKS IN CENTRAL VIRGINIA BUT THIS WILL FILL IN
QUICKLY THIS AFTERNOON AND THIS LIMITS THE HEATING. ALSO LAPSE
RATES ARE FAIRLY WEAK LIMITING INSTABILITY. ALSO WHILE THE SHEAR
DOES INCREASE TOWARD EVENING BY THEN THE INSTABILITY IS WEAKENING.
DO BELIEVE THERE WILL BE SOME THUNDER THIS EVENING WITH THE STRONG
LIFT AND CAN NOT RULE OUT AN ISOLATED WET MICRO BURST BUT EXPECT
ANY SEVERE TO BE VERY LIMITED.
BECAUSE OF SOME BREAKS IN CLOUDS IN THE WEST RAISED MAXES THERE A
LITTLE WHILE LOWERED THEM FARTHER TO THE EAST. THIS CORRESPONDS
WELL WITH HRRR AND RUC AS WELL AS GRIDDED LAMP DATA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
EXPECT A "JUMP" IN THE FRONTAL BOUNDARY TO COASTAL SECTIONS EARLY
THIS EVENING BEHIND FIRST EXITING S/W. SECOND (POST FRONTAL) IMPULSE
THEN PROGGED TO QUICKLY MOVE NE ALONG THE BOUNDARY THIS EVENING
KEEPING CATEGORICAL POPS GOING MOST AREAS. HEAVIEST RAINFALL EXPECTED
EAST OF I95 AND HAVE ADDED LOCALLY HEAVY RAINFALL TO THE COUNTIES
AROUND AND EAST OF THE CHES BAY THIS EVENING. ANY SEVERE THREAT ENDS
QUICKLY THIS EVENING.
FRONT MOVES OFFSHORE AROUND OR SHORTLY AFTER MIDNIGHT. PCPN CHANCES
QUICKLY TAPER OFF (AND END ACROSS WESTERN HALF OF FA) AS SECOND S/W
PULLS AWAY FROM THE REGION. TEMPS FALL INTO THE 50S AS CAA REMAINS
RATHER WEAK. EXPECT A WIDE QPF WITH THIS SYSTEM. AROUND .50 INCH
ACROSS EXTREME WESTERN COUNTIES UPWARDS TO 1.50 INCHES ACROSS SERN
AREAS WHERE THE HEAVIEST RAINFALL IS EXPECTED.
SOME LINGERING SHWRS ALONG THE IMMEDIATE COASTAL AREAS PUSH OFFSHORE
ARND 12Z THURSDAY. LARGE RIDGE OF HIGH PRESSURE PROGGED TO BUILD INTO
REGION THURSDAY AFTERNOON AND FRIDAY. LINGERING WRAP ARND MSTR MAY
ENHANCE AFTERNOON SC ACROSS LWR MD ERN SHORE THURSDAY. OTW...TSCTNS
SHOW A QUICK COLUMN DRYING SO IT SHOULD END UP M SUNNY. DESPITE THE
INCREASING SUNSHINE...CAA KEEPS TEMPS IN THE L-M70S. CLEAR AND COOL
THURSDAY NIGHT. LOWS M40S-M50S. RIDGE AXIS STILL WEST OF FA FRIDAY.
M SUNNY WITH HIGHS IN THE L-M70S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
HIGH PRESSURE GRADUALLY MOVES OFFSHORE THIS WEEKEND WITH THE NEXT
FRONT APPROACHING BY MONDAY. RETURN FLOW RESULTS IN A GRADUAL WARMUP.
LATEST DATA SUGGESTS HIGHS THIS WEEKEND BETWEEN 75-80 SO HAVE BUMBED
UP TEMPS A BIT. PATTERN SLOWLY TRANSITIONS TO A WET PATTERN TOWARD
THE MIDDLE OF NEXT WEEK. MODELS HAVE SOME CHANGES THAT COULD AFFECT
OUR WEATHER NEXT WEEK. KEPT POPS AT 20 PERCENT SUNDAY NIGHT THROUGH
MONDAY NIGHT AS CONFIDENCE IN PCPN IS NOT HIGH ENOUGH TO MENTION IN
THE FCST. LOW PRESSURE SLOWLY PULLS NORTHEAST FROM THE WESTERN GULF
COAST REGION AND BRINGS A GOOD CHANCE FOR PCPN BY TUESDAY. WENT NO
HIGHER THAN 30 PERCENT THIS FAR OUT AS THE TIMING COULD CHANGE.
HIGHS IN THE 70S NEXT WEEK WITH LOWS IN THE 50S.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
COLD FRNT SLOWLY APPROACHING FROM THE WEST WILL CONTINUE TO USHER
IN MVFR/VFR CLOUD DECKS THRU THE MRNG HRS. TEMPO GROUP INCLUDED
FOR -RA AT ALL TAF SITES OVR NEXT FEW HRS WITH HIT OR MISS SHOWERS
ACROSS THE AREA. IFR CIGS POSSIBLE BUT KEPT OUT OF TAFS FOR NOW
DUE TO LOW CONFIDENCE. LIGHT TO MODERATE RAIN EXPECTED DURING THE
SECOND HALF OF THE DAY...WITH THUNDER POSSIBLE AS WELL...SE VA/NE
NC WILL HAVE THE BEST CHANCE FOR STORMS. LOW CIGS WILL PERSIST
INTO THE OVRNGT HRS.
CLOUDS WILL LINGER INTO THU MRNG AS HIGH PRES BUILDS IN FROM THE
WEST. VFR CONDS WILL THEN PREVAIL THRU THE WEEKEND.
&&
.MARINE...
HIGH PRES PERSISTS OFF TO THE EAST AS A COLD FRNT APPROACHES FROM
THE WEST TDY. SCA HAS BEEN DROPPED FOR THE MOUTH OF THE BAY WHERE
WAVES HAVE STAYED BELO 4 FT. ELSEWHERE...SOUTHERLY WINDS ARE JUST
BELO SCA THRESHOLDS OVR THE BAY...AND SPEEDS SHUD DIMINISH BY MIDDAY
AS THE 925 MB JET STREAK WEAKENS. THE SCA OVR COASTAL WATERS
CONTINUES THRU TNGT WITH 4-5 FT SEAS EXPECTED IN ASSOCIATION WITH
A PROLONGED S/SE FETCH AND 15-20 KT WINDS. WINDS OVR THE BAY MAY
REACH SCA THRESHOLDS FOR A SHORT DURATION TNGT WITH THE
FROPA...BUT WILL HOLD OFF ON ANY HEADLINES FOR THIS ATTM DUE TO
THE SHORT DURATION AND TIMING UNCERTAINTIES.
BEYOND TNGT...THE NEXT CHANCE FOR MARGINAL SCA CONDS WILL OCCUR
BEHIND THE COLD FRNT THU WITH W/NW WINDS. ANOTHER WEAK SURGE MAY
ARRIVE FRI MRNG. QUIET CONDS OVR THE WATERS INTO THE WEEKEND WITH
HIGH PRES IN PLACE.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EDT THURSDAY FOR ANZ654-656-
658.
SMALL CRAFT ADVISORY UNTIL 4 AM EDT THURSDAY FOR ANZ650-652.
&&
$$
SYNOPSIS...MPR
NEAR TERM...MPR/JAB
SHORT TERM...MPR
LONG TERM...MPR/LSA
AVIATION...MAS
MARINE...MAS
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
956 AM EDT WED MAY 9 2012
.SYNOPSIS...
A COLD FRONT OVER THE APPALACHIANS WILL SLOWLY MOVE ACROSS THE
AREA TODAY...THEN WILL PUSH OFF THE MID ATLANTIC COAST TONIGHT.
HIGH PRESSURE BUILDS IN FROM THE WEST ON THURSDAY...AND WILL HOLD
OVER THE AREA THROUGH SATURDAY. THE NEXT COLD FRONT WILL APPROACH
FROM THE WEST ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
SURFACE TROUGH/FRONTAL BOUNDARY ALONG THE INTERSTATE 95 CORRIDOR
THIS MORNING. PRECIP ASSOCIATED WITH THIS FEATURE HAS BEGUN TO SHIFT
EAST OF THE FORECAST AREA...WITH SOME LINGERING SHOWERS ALONG THE
WESTERN SHORE OF THE CHESAPEAKE BAY.
THERE WILL BE A LULL IN PRECIP DURING THE LATE MORNING AND EARLY
AFTERNOON HOURS ACROSS THE CWFA. A SECOND FRONTAL BOUNDARY CURRENTLY
ACROSS THE EASTERN OHIO VALLEY IS EXPECTED TO MOVE ACROSS THE CWFA
LATER THIS AFTERNOON INTO THE EVENING HOURS ACCOMPANIED BY ANOTHER
ROUND OF PRECIP.
LATEST HRRR RUNS SHOWS A BROKEN LINE OF SHOWERS AND THUNDERSTORMS
DEVELOPING ACROSS THE EASTERN THIRD OF THE CWFA AFTER 18Z. THIS LINE
WILL MOVE OFFSHORE DURING THE EVENING HOURS. THE BEST CHANCE
THUNDERSTORMS WILL BE EAST OF THE I-95 CORRIDOR...WHERE MARGINAL
SURFACE INSTABILITY WILL RESIDE. A FEW STRONG STORMS WILL BE
POSSIBLE...BUT SEVERE WEATHER IS NOT ANTICIPATED AT THIS TIME.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
COLD FRONT WILL HAVE MOVED OFF THE MID ATLANTIC COAST BY 12Z
THURSDAY...TAKING THE RAINFALL WITH IT. MODELS SHOW DECENT COLD/DRY
ADVECTION BEHIND THE FRONT DURING THE DAYTIME THURSDAY ON NORTHWEST
WINDS. THIS WILL MEAN A RETURN OF SUNSHINE...AND WITH SUNSHINE AND
COLD ADVECTION THERE WILL BE DECENT MIXING FOR WIND GUSTS OF 25 TO
30 MPH FROM MID-MORNING THROUGH AFTERNOON. TEMPERATURES WILL BE
COOLER ON THURSDAY...ALTHOUGH SUNSHINE AND A DOWNSLOPING COMPONENT
EAST OF THE MTNS WILL HELP OFFSET THE IMPACT OF COLD ADVECTION
SOME. STAYED CLOSE TO MOS.
WIND GUSTS ARE EXPECTED TO DIMINISH THURSDAY EVENING...AS HIGH
PRESSURE BUILDS IN FROM THE WEST PROMOTING MOSTLY CLEAR SKIES.
RADIATIONAL COOLING WILL SUPPORT MINIMA AT LEAST SEVERAL DEGREES
BELOW CLIMO...AROUND 50 IN DOWNTOWN WASHINGTON/BALTIMORE TO LOWER TO
MID 40S IN THE SUBURBS AND MID TO UPPER 30S OVER THE POTOMAC
HIGHLANDS.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE WILL REMAIN IN CONTROL OVER THE MID ATLANTIC
FRIDAY/SATURDAY...WITH TEMPERATURES MODERATING BACK ABOVE CLIMO FOR
SATURDAY WITH HIGHER HEIGHTS FROM THE UPPER RIDGE. EXPECT MOSTLY
CLEAR NIGHTS/MOSTLY SUNNY DAYS FRIDAY/SATURDAY UNDER HIGH PRESSURE.
SURFACE HIGH PRESSURE MOVES OFF THE COAST SUNDAY...WITH A RETURN
FLOW LIKELY TO BRING AN INCREASE IN CLOUDS. COLD FRONT WILL APPROACH
FROM THE WEST ON SUNDAY...BUT IS MORE LIKELY TO AFFECT THE CWA EARLY
NEXT WEEK WITH A CHANCE OF SHOWERS AND THUNDERSTORMS.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
CIGS AT THE TERMINAL SITES ARE MVFR/VFR THIS MORNING. DO EXPECT
SKIES TO REMAIN CLOUDY THROUGH THE REMAINDER OF THE MORNING INTO
MUCH OF THE OVERNIGHT HOURS. IFR CIGS/VSBYS ARE POSSIBLE IN
THUNDERSTORMS ACROSS THE EASTERN TERMINAL SITES THIS AFT/EVE.
HIGH PRESSURE BEGINS TO BUILD IN FROM THE WEST ON THURSDAY...AND
HOLDS ACROSS THE AREA INTO THE FIRST PART OF THE WEEKEND. VFR
EXPECTED THROUGH THIS PERIOD. MAIN IMPACT ON THURSDAY WILL BE
WINDS...FROM THE NORTHWEST AND GUSTING AOA 25 KT FROM MID-MORNING
THROUGH AFTERNOON. NO SIGNIFICANT WX EXPECTED FRIDAY/SATURDAY...THEN
THE NEXT COLD FRONT APPROACHES FROM THE WEST ON SUNDAY.
&&
.MARINE...
SMALL CRAFT ADVISORY EXPIRED AT 8 AM. SOUTHERLY FLOW CONTINUES
ACROSS THE WATERS THROUGH THE AFTERNOON...AOB 15 KT. SHOWERS AND
THUNDERSTORMS ARE LIKELY THIS AFTERNOON AND EVENING.
NORTHWEST WINDS WITH THE AID OF COLD ADVECTION LOOK TO BRING SMALL
CRAFT ADVISORY CONDITIONS OVER THE WATERS ON THURSDAY. THEY MAY
LINGER INTO THE EVENING /FOURTH PERIOD/ HOWEVER WITH LOWER
CONFIDENCE DID NOT EXTEND SCA THIS FAR. HIGH PRESSURE BUILDS IN
FRIDAY AND THIS WEEKEND. STILL MAY HAVE MARGINAL SCA CONDITIONS OVER
PORTIONS OF THE WATERS FRIDAY...THEN LESS WIND EXPECTED OVER THE
WEEKEND.
&&
.TIDES/COASTAL FLOODING...
ANOMALIES CONTINUE AROUND 1 FOOT ABOVE NORMAL. COASTAL FLOOD
ADVISORY IS ALREADY IN EFFECT THROUGH 1 PM FOR THE MORNING/MIDDAY
HIGH TIDE CYCLE FOR LOCATIONS ON THE WESTERN SHORE OF THE NORTHERN
CHESAPEAKE BAY AND ON THE UPPER TIDAL POTOMAC RIVER NEAR
ALEXANDRIA AND WASHINGTON D.C. ADVISORY IS MAINLY FOR SENSITIVE
AREAS VULNERABLE TO MINOR COASTLINE INUNDATION...SUCH AS
ALEXANDRIA AND ANNAPOLIS.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...COASTAL FLOOD ADVISORY UNTIL 1 PM EDT THIS AFTERNOON FOR
DCZ001.
MD...COASTAL FLOOD ADVISORY UNTIL 1 PM EDT THIS AFTERNOON FOR
MDZ007-011-014.
VA...COASTAL FLOOD ADVISORY UNTIL 1 PM EDT THIS AFTERNOON FOR
VAZ054.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EDT THURSDAY FOR
ANZ530>543.
&&
$$
UPDATE...LISTEMAA
AREA FORECAST DISCUSSION...UPDATED
NWS MARQUETTE MI
921 AM EDT WED MAY 9 2012
.UPDATE...
ISSUED AT 919 AM EDT WED MAY 9 2012
FCST IN PRETTY GOOD SHAPE. ADDED FOG THROUGH 14Z OVR FAR WEST BUT
THIS IS FADING FAST. TWEAKED SKY COVER UP OVER EASTERN CWA FOR
MORNING AS THERMAL TROUGH /H85 TEMPS -2C/ SLIDES IN ON PERIPHERY
OF UPPER TROUGH MOVING ACROSS GREAT LAKES. RUC 900MB RH SHOWS THIS
WELL BUT ALSO INDICATES DAYTIME MIXING AND STABILIZING FLOW OFF LK
SUPERIOR WILL SIGNIFICANTLY DECREASE CLOUDS BY EARLY AFTN. &&
.SYNOPSIS...
ISSUED AT 441 AM EDT WED MAY 9 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF OVER THE GULF OF
ALASKA...A DOWNSTREAM RIDGE EXTENDING FROM THE ROCKIES TO NUNAVUT
AND A TROF EXTENDING FROM QUEBEC THRU THE WRN GREAT LAKES. WITH A
SLOWLY PROGRESSIVE PATTERN...A QUIET 2-3 DAYS ARE ON THE WAY AS THE
UPSTREAM RIDGE SHIFTS E IN RESPONSE TO TROF MOVING INLAND FROM THE
GULF OF ALASKA. TROF WILL REACH THE UPPER LAKES LATE FRI...BRINGING
THE NEXT CHC OF -SHRA. AFTER A COOL DAY TODAY...A WARMING TREND WILL
GET UNDER WAY THU AND FRI AS WAA PATTERN DEVELOPS AHEAD OF THE TROF.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 441 AM EDT WED MAY 9 2012
WITH TROF AXIS SHIFTING SE OF UPPER MI...BACK EDGE OF
MOISTURE/CLOUDS IS PROGRESSING STEADILY SE ACROSS LAKE SUPERIOR
ATTM. PLENTY OF DRY AIR IN AN ABSOLUTE AND RELATIVE SENSE IS NOTED
UPSTREAM PER 00Z CWPL SOUNDING WHICH SHOWED PRECIPITABLE WATER OF
0.24 INCHES (AROUND 50PCT OF NORMAL) AND DWPT DEPRESSIONS GENERALLY
IN THE 10-25C RANGE FROM THE SFC TO ABOUT 500MB. WITH THE INFLUX OF
DRY AIR...THE FEW -SHRA/SPRINKLES NOTED ON KMQT RADAR WILL END IN
THE NEXT FEW HRS...AND CLOUDS WILL CLEAR OUT FROM NW TO SE TODAY. NOT
MUCH DIURNAL CU WAS NOTED UPSTREAM IN NRN ONTARIO YESTERDAY AFTN.
SHOULD BE A SIMILAR SITUATION HERE TODAY. THIS IDEA IS SUPPORTED BY
THE CU RULE WHICH SUGGESTS SCT DEVELOPMENT EARLIER IN THE DAY BEFORE
MIXING OF DRIER AIR BEGINS TO EAT AWAY AT THE CU. STABILIZING
INFLUENCE OF COOL FLOW OFF LAKE SUPERIOR WILL KEEP DAYTIME CU
INLAND...WITH CU PROGRESSIVELY FARTHER INLAND WITH TIME AS MARINE
LAYER INFLUENCE EXPANDS S. IT WILL BE A COOL DAY WITH 850MB
THERMAL TROF AROUND 0C SLOWLY SLIPPING E DURING THE AFTN. LOCATIONS
ALONG THE LAKE SUPERIOR SHORELINE SHOULD HOLD TO THE LOW/MID
40S...COOLEST OVER THE E. MIXING TO AROUND 800MB YIELDS MAX TEMPS IN
THE UPPER 50S/AROUND 60 TOWARD THE WI BORDER...WHICH IS INLINE WITH
UPSTREAM TEMPS IN NRN ONTARIO YESTERDAY.
AFTER A COOL DAY TODAY...STAGE WILL BE SET FOR A CHILLY/FROSTY
NIGHT TONIGHT AS SFC HIGH PRES RIDGE DRIFTS OVER THE AREA...
RESULTING IN WINDS DIMINISHING TO CALM/NEAR CALM UNDER MOSTLY CLEAR
SKIES. WITH PRECIPITABLE WATER RUNNING 50-75PCT OF NORMAL...
CONTINUED TO LEAN TOWARD THE LOW END OF AVBL GUIDANCE GIVEN THE
FAVORABLE RADIATIONAL COOLING CONDITIONS. TRADITIONAL COLD SPOTS IN
THE INTERIOR...ESPECIALLY W HALF...MAY SLIP INTO THE UPPER 20S. THAT
SAID...ONE POTENTIAL ISSUE THAT MAY LIMIT COOLING IS SOME CLOUD
COVER. MODELS SUGGEST THAT MID CLOUDS CURRENTLY OVER NRN MANITOBA AT
THE NOSE OF SOME WAA COULD DROP SE OVER THE AREA TONIGHT. SINCE THAT
WAA WEAKENS TO THE SE...EXPECT THE MID CLOUDS TO SHOW AT LEAST SOME
DECREASE IN COVERAGE AS THEY HEAD TOWARD THE AREA. OBVIOUSLY...CLOUD
TRENDS UPSTREAM TODAY WILL BE SOMETHING TO MONITOR DUE TO THE
POSSIBLE AFFECT ON MIN TEMPS TONIGHT.
UNDER SUNNY SKIES...A WARMER DAY IS EXPECTED THU WITH HIGH PRES IN
CONTROL AND 850MB TEMPS RISING TO 6 TO 10C BY LATE IN THE DAY. TEMPS
SHOULD REBOUND TO NEAR OR SLIGHTLY ABOVE NORMAL THOUGH LAKE BREEZES
SHOULD RULE LATE MORNING THRU THE AFTN TO PROVIDE COOLING NEAR THE
LAKES. MIXING UPWARDS OF 750MB YIELDS MAX TEMPS AROUND 70F OVER THE
INTERIOR W. TEMPS LAKESIDE WILL BE IN THE 40S/50S...DEPENDING ON HOW
EARLY LAKE BREEZE DEVELOPS AT EACH LOCATION.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 441 AM EDT WED MAY 9 2012
NAM SHOWS A 500 MB RIDGE OVER THE UPPER MISSISSIPPI RIVER VALLEY 00Z
FRI WITH TROUGHING AND A CLOSED LOW OVER NEW ENGLAND AND THE EASTERN
U.S...A CLOSED 500 MB LOW AND TROUGH NEAR IN NE MEXICO...AND A
TROUGH IN THE NORTHERN ROCKIES. THE 500 MB RIDGE MOVES INTO THE
UPPER GREAT LAKES ON FRIDAY. THE SHORTWAVE OVER THE NORTHERN ROCKIES
MOVES INTO THE UPPER GREAT LAKES FRIDAY NIGHT.
NAM BRINGS IN SOME 850-500 MB Q-VECTOR CONVERGENCE WITH DEEPER
MOISTURE MOVING IN FRI AFTERNOON INTO SAT MORNING. GFS AND ECMWF
SHOW THE SAME THING FRI AFTERNOON INTO SAT MORNING. WHAT THAT WILL
MEAN IS CHANCE POPS MOVING ACROSS THE CWA FRIDAY AFTERNOON THROUGH
FRIDAY NIGHT...THEN SATURDAY LOOKS DRY AS THE FRONT AND NARROW BAND
OF PCPN MOVE OUT. REMOVED POPS OVER THE EAST ON SATURDAY AS THE
FRONT IS WELL SOUTH AND EAST OF THE AREA BY THEN. THIS IS THE ONLY
CHANGE I MADE IN THE MID TERM. TEMPERATURES LOOKED GOOD AND LEFT
THEM ALONE FOR THE MOST PART.
IN THE EXTENDED...PROLONGED DRY PERIOD CONTINUES WITH THE NEXT
CHANCE FOR PCPN LATE ON TUESDAY. ECMWF SHOWS THE UPPER GREAT LAKES
STAYING IN A BROAD 500 MB TROUGH...BUT ALL THE DYNAMICS STAY NORTH
OF THE AREA UNTIL A TROUGH DIGS TO THE SOUTHEAST LATE ON TUESDAY.
TEMPERATURES THIS PERIOD LOOK TO BE NEAR NORMAL TO SLIGHTLY ABOVE
NORMAL WITH A SLOW WARMING TREND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 659 AM EDT WED MAY 9 2012
MUCH DRIER AIR ARRIVING AHEAD OF HIGH PRES WILL BRING VFR CONDITIONS
TO KIWD/KCMX/KSAW THRU THIS FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 441 AM EDT WED MAY 9 2012
THE DENSE FOG OVER THE LAKE LOOKS TO BE DONE AS NO SHIP OBS OR
OBSERVATION HAVE SHOWN IT THE PAST FEW HOURS AND CARIBOU ISLAND HAS
A 6 DEGREE TEMP/DEW POINT SPREAD. THE DRIER AIR HAS MOVED OVER THE
LAKE AND HELPED TO DISSIPATE THE FOG. LACK OF SIGNIFICANT WEATHER
FEATURES WILL RESULT IN WINDS MOSTLY UNDER 20KT ACROSS LAKE SUPERIOR
THRU THE END OF THE WEEK. NO GALES SEEN ANYTIME SOON.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SYNOPSIS...ROLFSON
SHORT TERM...ROLFSON
LONG TERM...07
AVIATION...ROLFSON
MARINE...07
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
700 AM EDT WED MAY 9 2012
.SYNOPSIS...
ISSUED AT 441 AM EDT WED MAY 9 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF OVER THE GULF OF
ALASKA...A DOWNSTREAM RIDGE EXTENDING FROM THE ROCKIES TO NUNAVUT
AND A TROF EXTENDING FROM QUEBEC THRU THE WRN GREAT LAKES. WITH A
SLOWLY PROGRESSIVE PATTERN...A QUIET 2-3 DAYS ARE ON THE WAY AS THE
UPSTREAM RIDGE SHIFTS E IN RESPONSE TO TROF MOVING INLAND FROM THE
GULF OF ALASKA. TROF WILL REACH THE UPPER LAKES LATE FRI...BRINGING
THE NEXT CHC OF -SHRA. AFTER A COOL DAY TODAY...A WARMING TREND WILL
GET UNDER WAY THU AND FRI AS WAA PATTERN DEVELOPS AHEAD OF THE TROF.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 441 AM EDT WED MAY 9 2012
WITH TROF AXIS SHIFTING SE OF UPPER MI...BACK EDGE OF
MOISTURE/CLOUDS IS PROGRESSING STEADILY SE ACROSS LAKE SUPERIOR
ATTM. PLENTY OF DRY AIR IN AN ABSOLUTE AND RELATIVE SENSE IS NOTED
UPSTREAM PER 00Z CWPL SOUNDING WHICH SHOWED PRECIPITABLE WATER OF
0.24 INCHES (AROUND 50PCT OF NORMAL) AND DWPT DEPRESSIONS GENERALLY
IN THE 10-25C RANGE FROM THE SFC TO ABOUT 500MB. WITH THE INFLUX OF
DRY AIR...THE FEW -SHRA/SPRINKLES NOTED ON KMQT RADAR WILL END IN
THE NEXT FEW HRS...AND CLOUDS WILL CLEAR OUT FROM NW TO SE TODAY. NOT
MUCH DIURNAL CU WAS NOTED UPSTREAM IN NRN ONTARIO YESTERDAY AFTN.
SHOULD BE A SIMILAR SITUATION HERE TODAY. THIS IDEA IS SUPPORTED BY
THE CU RULE WHICH SUGGESTS SCT DEVELOPMENT EARLIER IN THE DAY BEFORE
MIXING OF DRIER AIR BEGINS TO EAT AWAY AT THE CU. STABILIZING
INFLUENCE OF COOL FLOW OFF LAKE SUPERIOR WILL KEEP DAYTIME CU
INLAND...WITH CU PROGRESSIVELY FARTHER INLAND WITH TIME AS MARINE
LAYER INFLUENCE EXPANDS S. IT WILL BE A COOL DAY WITH 850MB
THERMAL TROF AROUND 0C SLOWLY SLIPPING E DURING THE AFTN. LOCATIONS
ALONG THE LAKE SUPERIOR SHORELINE SHOULD HOLD TO THE LOW/MID
40S...COOLEST OVER THE E. MIXING TO AROUND 800MB YIELDS MAX TEMPS IN
THE UPPER 50S/AROUND 60 TOWARD THE WI BORDER...WHICH IS INLINE WITH
UPSTREAM TEMPS IN NRN ONTARIO YESTERDAY.
AFTER A COOL DAY TODAY...STAGE WILL BE SET FOR A CHILLY/FROSTY
NIGHT TONIGHT AS SFC HIGH PRES RIDGE DRIFTS OVER THE AREA...
RESULTING IN WINDS DIMINISHING TO CALM/NEAR CALM UNDER MOSTLY CLEAR
SKIES. WITH PRECIPITABLE WATER RUNNING 50-75PCT OF NORMAL...
CONTINUED TO LEAN TOWARD THE LOW END OF AVBL GUIDANCE GIVEN THE
FAVORABLE RADIATIONAL COOLING CONDITIONS. TRADITIONAL COLD SPOTS IN
THE INTERIOR...ESPECIALLY W HALF...MAY SLIP INTO THE UPPER 20S. THAT
SAID...ONE POTENTIAL ISSUE THAT MAY LIMIT COOLING IS SOME CLOUD
COVER. MODELS SUGGEST THAT MID CLOUDS CURRENTLY OVER NRN MANITOBA AT
THE NOSE OF SOME WAA COULD DROP SE OVER THE AREA TONIGHT. SINCE THAT
WAA WEAKENS TO THE SE...EXPECT THE MID CLOUDS TO SHOW AT LEAST SOME
DECREASE IN COVERAGE AS THEY HEAD TOWARD THE AREA. OBVIOUSLY...CLOUD
TRENDS UPSTREAM TODAY WILL BE SOMETHING TO MONITOR DUE TO THE
POSSIBLE AFFECT ON MIN TEMPS TONIGHT.
UNDER SUNNY SKIES...A WARMER DAY IS EXPECTED THU WITH HIGH PRES IN
CONTROL AND 850MB TEMPS RISING TO 6 TO 10C BY LATE IN THE DAY. TEMPS
SHOULD REBOUND TO NEAR OR SLIGHTLY ABOVE NORMAL THOUGH LAKE BREEZES
SHOULD RULE LATE MORNING THRU THE AFTN TO PROVIDE COOLING NEAR THE
LAKES. MIXING UPWARDS OF 750MB YIELDS MAX TEMPS AROUND 70F OVER THE
INTERIOR W. TEMPS LAKESIDE WILL BE IN THE 40S/50S...DEPENDING ON HOW
EARLY LAKE BREEZE DEVELOPS AT EACH LOCATION.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 441 AM EDT WED MAY 9 2012
NAM SHOWS A 500 MB RIDGE OVER THE UPPER MISSISSIPPI RIVER VALLEY 00Z
FRI WITH TROUGHING AND A CLOSED LOW OVER NEW ENGLAND AND THE EASTERN
U.S...A CLOSED 500 MB LOW AND TROUGH NEAR IN NE MEXICO...AND A
TROUGH IN THE NORTHERN ROCKIES. THE 500 MB RIDGE MOVES INTO THE
UPPER GREAT LAKES ON FRIDAY. THE SHORTWAVE OVER THE NORTHERN ROCKIES
MOVES INTO THE UPPER GREAT LAKES FRIDAY NIGHT.
NAM BRINGS IN SOME 850-500 MB Q-VECTOR CONVERGENCE WITH DEEPER
MOISTURE MOVING IN FRI AFTERNOON INTO SAT MORNING. GFS AND ECMWF
SHOW THE SAME THING FRI AFTERNOON INTO SAT MORNING. WHAT THAT WILL
MEAN IS CHANCE POPS MOVING ACROSS THE CWA FRIDAY AFTERNOON THROUGH
FRIDAY NIGHT...THEN SATURDAY LOOKS DRY AS THE FRONT AND NARROW BAND
OF PCPN MOVE OUT. REMOVED POPS OVER THE EAST ON SATURDAY AS THE
FRONT IS WELL SOUTH AND EAST OF THE AREA BY THEN. THIS IS THE ONLY
CHANGE I MADE IN THE MID TERM. TEMPERATURES LOOKED GOOD AND LEFT
THEM ALONE FOR THE MOST PART.
IN THE EXTENDED...PROLONGED DRY PERIOD CONTINUES WITH THE NEXT
CHANCE FOR PCPN LATE ON TUESDAY. ECMWF SHOWS THE UPPER GREAT LAKES
STAYING IN A BROAD 500 MB TROUGH...BUT ALL THE DYNAMICS STAY NORTH
OF THE AREA UNTIL A TROUGH DIGS TO THE SOUTHEAST LATE ON TUESDAY.
TEMPERATURES THIS PERIOD LOOK TO BE NEAR NORMAL TO SLIGHTLY ABOVE
NORMAL WITH A SLOW WARMING TREND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 659 AM EDT WED MAY 9 2012
MUCH DRIER AIR ARRIVING AHEAD OF HIGH PRES WILL BRING VFR CONDITIONS
TO KIWD/KCMX/KSAW THRU THIS FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 441 AM EDT WED MAY 9 2012
THE DENSE FOG OVER THE LAKE LOOKS TO BE DONE AS NO SHIP OBS OR
OBSERVATION HAVE SHOWN IT THE PAST FEW HOURS AND CARIBOU ISLAND HAS
A 6 DEGREE TEMP/DEW POINT SPREAD. THE DRIER AIR HAS MOVED OVER THE
LAKE AND HELPED TO DISSIPATE THE FOG. LACK OF SIGNIFICANT WEATHER
FEATURES WILL RESULT IN WINDS MOSTLY UNDER 20KT ACROSS LAKE SUPERIOR
THRU THE END OF THE WEEK. NO GALES SEEN ANYTIME SOON.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...ROLFSON
SHORT TERM...ROLFSON
LONG TERM...07
AVIATION...ROLFSON
MARINE...07
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
829 AM EDT WED MAY 9 2012
.SYNOPSIS...
AN UPPER LEVEL TROUGH EXTENDING FROM THE GREAT LAKES SOUTHWARD
THROUGH THE MID MISSISSIPPI VALLEY WILL AMPLIFY AND PROGRESS
EASTWARD TODAY...REACHING THE CENTRAL APPALACHIANS BY TONIGHT. THE
COLD FRONT OVER THE MID-ATLANTIC PIEDMONT WILL BECOME NEARLY
STATIONARY ALONG THE COASTAL PLAIN AS A SECONDARY WAVE OF LOW
PRESSURE DEVELOPS AND LIFTS NORTHWARD ALONG THE BOUNDARY. THE
FRONT WILL EVENTUALLY SHIFT OFFSHORE EARLY THURSDAY LEAVING BEHIND
A COOL AND GUSTY NORTHWEST FLOW. FAIR AND DRY WEATHER IS IN STORE
FOR FRIDAY THROUGH THE FIRST HALF OF THE UPCOMING WEEKEND WITH
HIGH PRESSURE RETURNING TO THE AREA.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
12Z RUC SFC ANALYSIS SHOWS LOW PRES CENTERED OVER SRN ONT CANADA
WITH COLD FRONT/SFC TROF EXTENDING SWD INTO ERN PA...E OF THE SUSQ
RVR. STILL NOT EXPECTING ANY PCPN THRU MID MORNING...WITH PATCHY
FOG AND LOW CLOUDS DISSIPATING BY 14Z. COSPA/HRRR DATA SHOWS
SCT -SHRA AND ISOLD -TSRA DEVELOPING IN THE UPPER OH VLY AND WRN
PA AFT 16Z.
THE UPPER TROF WILL AMPLIFY AS IT SHIFTS EWD INTO THE ERN GREAT
LAKES/UPPER OHIO VALLEY BY THIS EVE. CURRENT RADAR RETURNS OVER
WRN PA ARE NOT REACHING THE GROUND. COMBO OF LG SCALE LIFT AND
COOLING ALOFT/STEEPENING LAPSE RATES ASSOCD WITH THE APPROACHING
UPPER TROF WILL TRIGGER ISOLD-SCT SHOWERS OVR THE WRN ALLEGHENIES
DURING LATE MORNING/EARLY AFTN...WITH SIMILAR CVRG SPREADING EWD
INTO THE CENTRAL MTNS DURING PEAK HEATING. ALTHOUGH INSTABILITY
WILL BE LIMITED...CAN/T RULE OUT A RUMBLE OF TS IN OVR THE NW MTNS
WHERE 850-500MB LAPSE RATES NEAR 7 C/KM BY LATE IN THE DAY.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH 6 AM THURSDAY/...
HEIGHT FALLS CROSSING THE CENTRAL APPLCHNS WILL INDUCE A SECONDARY
WAVE OF LOW PRES WHICH WILL LIFT NWD ALONG THE SLOW-MOVG BNDRY OVER
THE MID-ATLC PIEDMONT/COASTAL PLAIN. MDLS AGREE THAT THE FAR ERN
ZONES WILL BE ON THE WRN EDGE OF MOD-LCLY HVY PCPN AXIS EXPECTED
ALONG THE MID-ATLC COAST AS THE SFC WAVE INTERACTS WITH RICH PLUME
OF DEEP MSTR/HI PWATS.
THE PATTERN EVENTUALLY EVOLVES TWD A TYPICAL COLD SEASON CYC/NWLY
FLOW REGIME...WITH DEEPENING SFC LOW LIFTING NWD ALONG THE SRN NEW
ENGLAND COAST. WNW WINDS WILL INCREASE ON THE BACKSIDE OF THE
DEPARTING SYS.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
MODELS ARE CONSISTENT THROUGH FRIDAY...AS THE EC TAKES A STRONG
UPPER LEVEL EAST...AND THE GFS MOVES THE SYSTEM NORTH...WITH A
SLIGHT RETROGRADE. A SHARP UPPER LEVEL RIDGE AND ASSOCIATED
1026-1029 MB SC HIGH BUILDS INTO THE REGION FRIDAY NIGHT INTO
SATURDAY. THE RIDGE CONTINUES TO TREND WEAKER AS IT SHOULD BE
FLATTENING OUT BY SATURDAY NIGHT AS SHORTWAVE ENERGY STREAKS SE
ACROSS THE UPPER GREAT LAKES. GUIDANCE DISAGREES ON THE TIMING OF
THIS SHORTWAVE...THE OPERATIONAL EC BRINGING IT THROUGH FASTER
THAN THE GFS.
DUE TO THE HIGH PRESSURE TEMPS SHOULD WARM BACK TOWARD NORMAL
WITH BELOW NORMAL CHANCES OF PCPN OCCURRING FRIDAY THROUGH SUNDAY.
THE NEXT CHC FOR ANY RAIN SHOWERS WILL COME LATE SUNDAY AFTERNOON
AND...DEPENDING ON THE PROGRESSION OF THE COLD FRONT HEADED ESE
FROM THE GREAT LAKES...WILL CONTINUE THROUGH SUNDAY NIGHT INTO
MONDAY MORNING.
&&
.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
LOW CIGS/FOG WILL GIVE WAY TO VFR AT ALL SITES BY 14Z. SCT -SHRA
AND ISOLD -TSRA ARE EXPECTED TO DEVELOP OVR THE ERN 1/2 OF ZOB
SECTOR AIRSPACE AFT 16Z...WITH CVRG LKLY EXPANDING EWD INTO
CENTRAL PA AND WRN PTNS OF ZNY SECTOR BY MID-LATE AFTN. GIVEN LIMITED
CVRG AND LOW POINT PROBS...ONLY OPTED TO INCLUDE VCSH AT JST/BFD. THE
OVERALL PATTERN WILL EVENTUALLY TRANSITION TO A COOL NWLY POST-
FRONTAL REGIME AS THE UPPER TROUGH CROSSES THE NE STATES AND LOW
PRES DEEPENS AS IT LIFTS NWD ALONG THE SRN NEW ENG COAST. IN THIS
PATTERN LOW CIGS ARE LKLY AT BFD/JST WITH MAINLY VFR E OF THE MTNS.
OUTLOOK...
THU...MVFR NORTH/WEST. VFR SOUTH/EAST. GUSTY NW WINDS.
FRI-SUN...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/STEINBUGL
NEAR TERM...DANGELO/STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...LAMBERT/GARTNER
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
753 AM EDT WED MAY 9 2012
.SYNOPSIS...
AN UPPER LEVEL TROUGH EXTENDING FROM THE GREAT LAKES SOUTHWARD
THROUGH THE MID MISSISSIPPI VALLEY WILL AMPLIFY AND PROGRESS
EASTWARD TODAY...REACHING THE CENTRAL APPALACHIANS BY TONIGHT. THE
COLD FRONT OVER THE MID-ATLANTIC PIEDMONT WILL BECOME NEARLY
STATIONARY ALONG THE COASTAL PLAIN AS A SECONDARY WAVE OF LOW
PRESSURE DEVELOPS AND LIFTS NORTHWARD ALONG THE BOUNDARY. THE
FRONT WILL EVENTUALLY SHIFT OFFSHORE EARLY THURSDAY LEAVING BEHIND
A COOL AND GUSTY NORTHWEST FLOW. FAIR AND DRY WEATHER IS IN STORE
FOR FRIDAY THROUGH THE FIRST HALF OF THE UPCOMING WEEKEND WITH
HIGH PRESSURE RETURNING TO THE AREA.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
12Z RUC SFC ANALYSIS SHOWS LOW PRES CENTERED OVER SRN ONT CANADA
WITH COLD FRONT/SFC TROF EXTENDING SWD INTO ERN PA...E OF THE SUSQ
RVR. STILL NOT EXPECTING ANY PCPN THRU MID MORNING...WITH PATCHY
FOG AND LOW CLOUDS DISSIPATING BY 14Z. COSPA/HRRR DATA SHOWS
SCT -SHRA AND ISOLD -TSRA DEVELOPING IN THE UPPER OH VLY AND WRN
PA AFT 16Z.
THE UPPER TROF WILL AMPLIFY AS IT SHIFTS EWD INTO THE ERN GREAT
LAKES/UPPER OHIO VALLEY BY THIS EVE. COMBO OF LG SCALE LIFT AND
COOLING ALOFT/STEEPENING LAPSE RATES ASSOCD WITH THE APPROACHING
UPPER TROF WILL TRIGGER ISOLD-SCT SHOWERS OVR THE WRN ALLEGHENIES
DURING LATE MORNING/EARLY AFTN...WITH SIMILAR CVRG SPREADING EWD
INTO THE CENTRAL MTNS MID BY PEAK HEATING. ALTHOUGH INSTABILITY
WILL BE LIMITED...CAN/T RULE OUT A RUMBLE OF TS IN OVR THE NW MTNS
WHERE 850-500MB LAPSE RATES NEAR 7 C/KM BY LATE IN THE DAY.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH 6 AM THURSDAY/...
HEIGHT FALLS CROSSING THE CENTRAL APPLCHNS WILL INDUCE A SECONDARY
WAVE OF LOW PRES WHICH WILL LIFT NWD ALONG THE SLOW-MOVG BNDRY OVER
THE MID-ATLC PIEDMONT/COASTAL PLAIN. MDLS AGREE THAT THE FAR ERN
ZONES WILL BE ON THE WRN EDGE OF MOD-LCLY HVY PCPN AXIS EXPECTED
ALONG THE MID-ATLC COAST AS THE SFC WAVE INTERACTS WITH RICH PLUME
OF DEEP MSTR/HI PWATS.
THE PATTERN EVENTUALLY EVOLVES TWD A TYPICAL COLD SEASON CYC/NWLY
FLOW REGIME...WITH DEEPENING SFC LOW LIFTING NWD ALONG THE SRN NEW
ENGLAND COAST. WNW WINDS WILL INCREASE ON THE BACKSIDE OF THE
DEPARTING SYS.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
MODELS ARE CONSISTENT THROUGH FRIDAY...AS THE EC TAKES A STRONG
UPPER LEVEL EAST...AND THE GFS MOVES THE SYSTEM NORTH...WITH A
SLIGHT RETROGRADE. A SHARP UPPER LEVEL RIDGE AND ASSOCIATED
1026-1029 MB SC HIGH BUILDS INTO THE REGION FRIDAY NIGHT INTO
SATURDAY. THE RIDGE CONTINUES TO TREND WEAKER AS IT SHOULD BE
FLATTENING OUT BY SATURDAY NIGHT AS SHORTWAVE ENERGY STREAKS SE
ACROSS THE UPPER GREAT LAKES. GUIDANCE DISAGREES ON THE TIMING OF
THIS SHORTWAVE...THE OPERATIONAL EC BRINGING IT THROUGH FASTER
THAN THE GFS.
DUE TO THE HIGH PRESSURE TEMPS SHOULD WARM BACK TOWARD NORMAL
WITH BELOW NORMAL CHANCES OF PCPN OCCURRING FRIDAY THROUGH SUNDAY.
THE NEXT CHC FOR ANY RAIN SHOWERS WILL COME LATE SUNDAY AFTERNOON
AND...DEPENDING ON THE PROGRESSION OF THE COLD FRONT HEADED ESE
FROM THE GREAT LAKES...WILL CONTINUE THROUGH SUNDAY NIGHT INTO
MONDAY MORNING.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
LOW CIGS/FOG WILL GIVE WAY TO VFR AT ALL SITES BY 14Z. SCT -SHRA
AND ISOLD -TSRA ARE EXPECTED TO DEVELOP OVR THE ERN 1/2 OF ZOB
SECTOR AIRSPACE AFT 16Z...WITH CVRG LKLY EXPANDING EWD INTO
CENTRAL PA AND WRN PTNS OF ZNY SECTOR BY MID-LATE AFTN. GIVEN LIMITED
CVRG AND LOW POINT PROBS...ONLY OPTED TO INCLUDE VCSH AT JST/BFD. THE
OVERALL PATTERN WILL EVENTUALLY TRANSITION TO A COOL NWLY POST-
FRONTAL REGIME AS THE UPPER TROUGH CROSSES THE NE STATES AND LOW
PRES DEEPENS AS IT LIFTS NWD ALONG THE SRN NEW ENG COAST. IN THIS
PATTERN LOW CIGS ARE LKLY AT BFD/JST WITH MAINLY VFR E OF THE MTNS.
OUTLOOK...
THU...MVFR NORTH/WEST. VFR SOUTH/EAST. GUSTY NW WINDS.
FRI-SUN...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...LAMBERT/GARTNER
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
600 AM CDT WED MAY 9 2012
.SHORT TERM...TODAY THROUGH FRIDAY
343 AM CDT WED MAY 9 2012
AT 3 AM...A TROUGH OF LOW PRESSURE WAS LOCATED JUST NORTH OF THE
INTERSTATE 90 CORRIDOR. THERE ARE A FEW SHOWERS STILL BEING
DETECTED BY RADAR JUST BEHIND THE TROUGH AXIS. NOT OVERLY
SURPRISED BY THIS...BECAUSE THE SAME THING WAS HAPPENING ACROSS
NORTHERN MINNESOTA ON TUESDAY MORNING. THE HRRR SUGGESTS THAT
THESE SHOWERS WILL DISSIPATE BY 09.12Z...SO KEPT THE FORECAST DRY
ACROSS THE AREA TODAY.
FOR TONIGHT AND EARLY THURSDAY MORNING...THE 09.00Z MODELS ARE IN
VERY GOOD AGREEMENT THAT THE 500 MB POTENTIAL VORTICITY ANOMALY
/CURRENTLY LOCATED OVER MONTANA/ WILL MOVE THROUGH THE FORECAST
AREA. THIS HAS BEEN A CONSISTENT SIGNAL OVER THE PAST COUPLE OF
DAYS. WITH MUCH OF THE MOISTURE ASSOCIATED WITH THIS SYSTEM IS
LOCATED ABOVE ABOVE 600 MB...ONLY EXPECTING A BROKEN DECK OF MID
AND HIGH CLOUDS. THESE CLOUDS WILL LIKELY LIMIT SOME OF NOCTURNAL
COOLING...SO RAISED THE TEMPERATURES BY A FEW DEGREES.
ON FRIDAY...ALL OF THE 09.00Z MODELS ARE IN VERY GOOD AGREEMENT
THAT A CANADIAN COLD FRONT WILL MOVE SOUTHEAST ACROSS
MINNESOTA...WESTERN IOWA...AND NORTHERN WISCONSIN. THIS FRONT WILL
HAVE LIMITED MOISTURE TO WORK DUE TO THE UPPER LEVEL LOW OVER TEXAS
PREVENTING THIS SYSTEM FROM TAPPING INTO GULF OF MEXICO MOISTURE.
WHILE THIS WILL BE CASE...MEAN LAYER CAPES STILL CLIMB INTO THE
500 TO 1000 J/KG RANGE AHEAD OF THIS FRONT. BUFKIT SOUNDINGS SHOW
THAT THERE WILL BE A CAP LOCATED BETWEEN 750 AND 650 MB. AS HAS
BEEN THE CASE OVER THE PAST SEVERAL DAYS...THE ECMWF CONTINUES TO
KEEP THE PRECIPITATION JUST WEST OF THE FORECAST AREA. MEANWHILE
THE GFS AND NAM/WRF HAVE COME AROUND TO GEM SOLUTION OF GENERATING
PRECIPITATION ACROSS THE ENTIRE AREA DURING THE AFTERNOON. THE
MAIN DIFFERENCE IS HOW FAST THE CAP ERODES. DUE TO THIS
UNCERTAINTY...JUST KEPT THE PRECIPITATION PROBABILITIES BETWEEN
25 AND 34 PERCENT. WITH WEAK 0-3 KM AND 0-6 KM SHEAR...IT STILL
DOES NOT LOOK LIKE THAT ANY OF THESE THUNDERSTORMS WOULD BECOME
SEVERE.
.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
343 AM CDT WED MAY 9 2012
ON FRIDAY NIGHT...ALL OF THE 09.00Z MODELS ARE IN FAIRLY GOOD
AGREEMENT THAT A COLD FRONT WILL MOVE SOUTHEAST THROUGH NORTHEAST
IOWA...AND SOUTHWEST AND CENTRAL WISCONSIN. THE INSTABILITY
GRADUALLY WANES DURING THE EVENING...THEREFORE...CONFINED THE
PRECIPITATION CHANCES TO MAINLY THE EVENING.
ON TUESDAY...THE LAST TWO RUNS OF THE ECMWF AND 09.00Z GFS
INDICATE THAT A WEAK SHORT WAVE TROUGH WILL MOVE SOUTHEAST ACROSS
NORTHERN MINNESOTA...NORTHERN WISCONSIN...AND SOUTHWEST ONTARIO.
OVERALL THE BEST FORCING WILL BE LOCATED TO THE NORTH AND EAST OF
THE FORECAST AREA. HOWEVER THE MEAN LAYER CAPES WILL RANGE FROM
500 TO 1000 J/JG...THIS WILL BE ENOUGH INSTABILITY FOR THE
POSSIBILITY OF SOME SCATTERED SHOWERS. THE 09.00Z GFS AND 08.12Z
ECMWF SUGGEST THAT THESE SHOWERS WOULD BE MAINLY NORTH OF
WISCONSIN 29. MEANWHILE THE 09.00Z ECMWF HAS THESE SHOWERS ACROSS
THE ENTIRE AREA. WITH THE BEST CONSISTENCY ACROSS TAYLOR AND
NORTHERN CLARK COUNTIES IN NORTH CENTRAL WISCONSIN...WENT WITH A
15 TO 24 PERCENT PRECIPITATION PROBABILITY AND LEFT THE REMAINDER
OF THE AREA DRY FOR NOW.
&&
.AVIATION...
600 AM CDT TUE MAY 8 2012
A BANK OF 6 KFT BKN CLOUDS WILL SLIDE SOUTHWARD ACROSS THE REGION
TODAY...WITH SATELLITE TRENDS SUGGESTING IT WILL MOVE SOUTH OF
KRST/KLSE BETWEEN 15-18Z. EXPECT SOME CU DEVELOPMENT POST THESE
CLOUDS FOR THE AFTERNOON...BUT SHOULD STAY VFR.
LIGHT WINDS TONIGHT AS A SFC HIGH WORKS OVERHEAD. COULD BE SOME FOG
CONCERNS WITH RECENT RAINS SATURATING THE GROUND. HOWEVER...CIRRUS
WILL SPILL ACROSS AN UPPER LEVEL RIDGE AND OVER THE REGION
TONIGHT. ALSO...EXPECT SOME DRYING THIS AFTERNOON. LATEST OBS ACROSS
NORTHERN MN HAVE AREAS OF FOG...BUT UNDER CLEAR SKIES. WILL LEAVE
FOG OUT OF THE TAFS FOR NOW. IF IT WOULD DEVELOP...KLSE IN THE RIVER
VALLEY WOULD HAVE THE GREATER POTENTIAL FOR VSBY RESTRICTIONS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
241 AM CDT WED MAY 9 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS DENVER CO
303 PM MDT WED MAY 9 2012
.SHORT TERM...CUMULUS FINALLY DEVELOPING ACROSS MOUNTAINS OF PARK
SUMMIT AND GRAND COUNTIES. AIRMASS DRIER WITH LOW PRECIPITABLE
WATER. LAPS SURFACE ANALYSIS SHOWING CAPES AROUND 200 J/KG IN THIS
AREA. LATEST RUC INDICATES 200-300 J/KG OF CAPE ACROSS THE
MOUNTAINS THROUGH THE EARLY EVENING. STILL CAN`T RULE OUT A FEW
HIGH BASED STORMS...AND WILL MAINTAIN THE SLIGHT CHANCE THROUGH
THE EARLY EVENING. FORECAST SOUNDINGS INDICATE POTENTIAL FOR MORE
WIND THAN RAIN. OTHERWISE...DRY CONDITIONS TO PREVAIL WITH MAINLY
CLEAR SKIES. WITH LIGHT DRAINAGE WINDS EXPECTED OVERNIGHT...LOWS
TO DROP INTO THE 40S ACROSS THE PLAINS...WITH SOME MID AND UPPER
30S IN LOW LYING AREAS. ON THURSDAY...UPPER LEVEL RIDGE OVER AREA TO
SHIFT EAST WITH FLOW ALOFT BECOMING SOUTHWEST. THIS FLOW TO ALLOW
SOME INCREASE IN MOISTURE ACROSS THE MOUNTAINS BY THE AFTERNOON.
WITH FAIRLY STEEP LAPSE RATES EXPECTED AND FORECAST CAPES AROUND
500 J/KG...IT APPEARS THAT THERE WILL BE A BETTER CHANCE FOR
THUNDERSTORMS OVER THE HIGH COUNTRY. BUT WITHOUT HELP FROM AN
UPPER LEVEL FEATURE...SLIGHT CHANCE POPS SHOULD SUFFICE FOR NOW.
WILL ALSO ADD A SLIGHT CHANCE OF STORMS TO THE FOOTHILLS LATE IN
THE DAY AS A FEW OF THE STORMS COULD MOVE ACROSS AREA. FORECAST
SOUNDINGS STILL SHOWING POTENTIAL FOR MORE WIND THAN RAIN. ACROSS
PLAINS...AIRMASS TOO DRY FOR ANY CONVECTION DESPITE THE FAIRLY
DECENT LAPSE RATES. TEMPERATURE AND THICKNESS PROGS AS WELL AS
GUIDANCE SHOW HIGHS IN THE LOWER TO MID 80S ACROSS PLAINS. THIS
LOOKS REASONABLE GIVEN AMOUNT OF WARM AIR ADVECTION EXPECTED. CURRENT
TEMPERATURE GRIDS IN LINE WITH GUIDANCE AND LOOKS REASONABLE.
.LONG TERM...UPPER LEVEL TROUGH WILL PASS WELL NORTH OF THE AREA
THURSDAY NIGHT...BUT IT WILL PUSH A COLD FRONT SOUTH THROUGH THE
AREA AROUND MIDNIGHT. MAY SEE A FEW HIGH BASED SHOWERS AND
THUNDERSTORMS AHEAD OF IT THURSDAY EVENING...THE BEST CHANCE BEING
OVER THR HIGHER TERRAIN. IT WILL BE MUCH COOLER BEHIND THE FRONT
ON FRIDAY WITH AREAS ALONG THE FRONT AND ACROSS THE EASTERN PLAINS
STRUGGLE TO CLIMB ABOVE 50 DEGREES. SHOULD BE ENOUGH MOISTURE AND
UPSLOPE FLOW TO KEEP CLOUDS OVER THE AREA FRIDAY. AIRMASS WILL BE
UNSTABLE OVER THE MOUNTAINS FRIDAY AFTERNOON. THIS COMBINED WITH
A SHORT WAVE WILL PRODUCE THUNDERSTORMS DURING THE AFTERNOON
HOURS. EAST OF THE CONTINENTAL DIVIDE...WINDS WILL TURN
EASTERLY...WHICH WILL ENHANCE THE UPSLOPE COMPONENT. EXPECT RAIN
AND SNOW TO BECOME WIDESPREAD BY FRIDAY EVENING OVER THE FRONT RANGE
AS THE UPPER LEVEL WAVE MOVES OVER. SNOW LEVEL WILL FALL TO 7000 TO
8000 FEET.
RAIN WILL LINGER INTO SATURDAY AS THE UPSLOPE FLOW CONTINUES.
HIGHS WILL AGAIN BE COOLER WITH READINGS AROUND 50 DEGREES. UPPER
LEVEL TROUGH WILL MOVE SOUTH ACROSS THE GREAT BASIN
SUNDAY. THIS SYSTEM WILL MAY BRING A ROUND OF AFTERNOON CONVECTION
TO THE HIGH COUNTRY. FOR THE PLAINS...IN ADDITION TO BEING TOO FAR
AWAY FROM THE UPPER LEVEL SYSTEM DRIER AIR WILL BE IN
PLACE. SO IF ANY SHOWERS FORM...THEY WILL BE LIGHT.
UPPER LEVEL RIDGE WILL MOVE OVER THE STATE EARLY NEXT WEEK.
CHANCES FOR CONVECTION WILL BE LOW UNDER THIS PATTERN.
TEMPERATURES WILL WARM TO SLIGHTLY ABOVE NORMAL BY TUESDAY.
&&
.AVIATION...LIGHT EASTERLY WINDS TO BECOME SOUTHWEST BY 02Z AS
DRAINAGE PATTERN DEVELOPS. WINDS TO THEN SHIFT TO THE SOUTHEAST
AFTER 18Z. VFR CONDITIONS TO PREVAIL. SLIGHT CHANCE OF
THUNDERSTORMS ALONG FOOTHILLS AFTER 21Z...SHOULD NOT AFFECT AREA
AIRPORTS.
&&
.HYDROLOGY...A FEW HIGH BASED STORMS POSSIBLE OVER THE MOUNTAINS
THIS EVENING WITH LIGHT RAINFALL EXPECTED. A SLIGHT CHANCE OF
THUNDERSTORMS MOUNTAINS AND FOOTHILLS AFTER 18Z WITH LIGHT RAIN.
NO HYDROLOGIC ISSUES ANTICIPATED.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....MEIER
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS NEW YORK NY
132 PM EDT WED MAY 9 2012
.SYNOPSIS...
A WARM FRONT CONTINUE TO HEAD NORTH OF THE TRI-STATE AREA THIS
MORNING...WITH A COLD FRONT MOVING INTO WESTERN PARTS OF THE
REGION BY LATE THIS AFTERNOON. AN AREA OF LOW PRESSURE WILL FORM
ALONG THE MID ATLANTIC COAST ALONG THE FRONT THIS EVENING...THEN
SLOWLY TRACK NORTHEAST ALONG THE FRONT INTO THE GULF OF MAINE BY
THURSDAY AFTERNOON...AND INTO THE WESTERN CANADIAN MARITIME
PROVINCES INTO THURSDAY NIGHT. A COLD FRONT MOVES THROUGH ON
FRIDAY. HIGH PRESSURE BUILDS IN FOR SATURDAY. A COLD FRONT
APPROACHES ON SUNDAY. IT WILL REMAIN UNSETTLED THROUGH THE MIDDLE
OF NEXT WEEK AS THE FRONT BECOMES STATIONARY AND DISTURBANCES RIDE
ALONG IT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MINOR ADJUSTMENTS WITH THIS UPDATE. POPS STILL HIGHER OVERALL OVER
EASTERN SECTIONS OF THE FORECAST AREA. FAR WESTERN ZONES COULD SEE
AN INCREASE IN SHOWER COVERAGE THIS AFTERNOON WITH DESTABILIZATION
AND A COLD FRONT NEARBY. A FEW MODELS...INCLUDING THE HRRR SHOW
THIS. SBCAPES ACCORDING TO LAPS DATA OVER THE WESTERN ZONES ARE
ALREADY UP TO AROUND 500 J/KG. THUNDERSTORMS THEREFORE POSSIBLE
THERE...AND WITH WET BULB ZERO HEIGHTS NEAR 8-9KFT...SMALL HAIL
NOT OUT OF THE QUESTION EITHER ASIDE FROM A STRONG GUST OR TWO.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
BASED ON MODEL SOUNDINGS...APPEARS THAT INSTABILITY SHOULD LAST
INTO THE FIRST PART OF THE EVENING...SO HAVE CARRIED A CHANCE OF
THUNDER THROUGH 00Z. OTHERWISE...THE NEXT ROUND OF HEAVIER
RAINFALL ARRIVES FOR THE SE 1/2 OF THE CWA TONIGHT IN RESPONSE TO
INCREASED FRONTOGENETIC AND DYNAMIC FORCING ASSOCIATED WITH THE
COASTAL LOW PASSING TO THE SE. THE NW 1/2 OF THE CWA SHOULD SEE
SCATTERED TO NUMEROUS SHOWERS DUE TO FORCING FROM AN APPROACHING
500 HPA TROUGH AND BEING IN THE RIGHT REAR QUADRANT OF A 120+ KT
300 HPA JET...ONCE AGAIN CHANCE POPS NW TO CATEGORICAL POPS SE.
FOR LOWS USED A BLEND OF 1/2 BIAS CORRECTED MAV GUIDANCE AND 1/4
EACH OF MET GUIDANCE AND NAM 2-METER TEMPERATURES. THIS YIELDED
VALUES AROUND 5 DEGREES ABOVE NORMAL.
PRECIPITATION SHOULD BEGIN TO SLOWLY TAPER OFF FROM NW TO SE FROM
LATE TONIGHT INTO THURSDAY MORNING AS THE COASTAL LOW AND
ASSOCIATED COLD FRONT PASS TO OUR EAST. BY THURSDAY AFTERNOON HAVE
MAINLY SLIGHT CHANCE POPS - CHANCE ACROSS THE WESTERN PORTION OF
THE NORTHERN INTERIOR ZONES...FOR INSTABILITY SHOWERS IN RESPONSE
TO THE 500 HPA TROUGH BUILDING INTO THE REGION. FOR HIGHS USED A
BLEND OF 30 PERCENT EACH OF MIXING DOWN FROM 825 HPA AND MAV AND
MET GUIDANCE AND 10 PERCENT NAM 2-METER TEMPERATURES. THIS
YIELDED TEMPERATURES AROUND NORMAL.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
SURFACE LOW PRESSURE CONTINUES TO MOVE AWAY FROM THE AREA THURSDAY
NIGHT...WHILE AN UPPER LEVEL TROUGH MOVES THROUGH. COLD FRONT MOVES
THROUGH DURING THE DAY ON FRIDAY...BUT NOT A LOT OF MOISTURE TO WORK
WITH AS A DRY WESTERLY FLOW WILL SHIFT TO THE NORTHWEST BEHIND THE
FRONT.
HIGH PRESSURE BUILDS IN FOR SATURDAY AND THE FIRST HALF OF SUNDAY.
RIDGING ALOFT BEGINS SATURDAY NIGHT INTO SUNDAY. SO HIGHS ON SUNDAY
SHOULD BE A COUPLE OF DEGREES WARMER THAN SATURDAY FOR INLAND
SECTIONS. TROUGH WILL DIG IN THE MIDDLE OF THE US ON
SUNDAY...PUSHING A COLD FRONT TOWARD THE EAST COAST. GFS DEVELOPS AN
OMEGA TYPE BLOCKING PATTERN DEVELOPS OVER THE WESTERN ATLANTIC AS
AN UPPER LEVEL LOW BECOMES CLOSED OFF OVER THE CENTRAL PLAINS LATE
MONDAY INTO TUESDAY. THIS MEANS AN EXTENDED PERIOD OF UNSETTLED
WEATHER AS THE COLD FRONT BECOMES STATIONARY NEAR THE REGION AND
DISTURBANCES RIDE ALONG THE BOUNDARY. THE ECMWF DOES NOT CUT OFF THE
LOW UNTIL WEDNESDAY NIGHT...SO THIS LENDS TO SOME MODEL DIFFERENCES
IN THE LONG TERM...BUT IT ALSO DEVELOPS THE OMEGA BLOCK.
CLIMATOLOGICALLY SPEAKING...SPRING IS THE TIME FOR BLOCKING
PATTERNS...SO WILL CARRY POPS THROUGH THE END OF THE LONG TERM
PERIOD. LIFTED INDICES BELOW 0 SUNDAY AFTERNOON...SO ADDED SLIGHT
CHANCE OF THUNDER FOR SOUTHWESTERN CT...LOWER HUDSON
VALLEY...NORTHEAST NJ...AND PORTIONS OF NEW YORK CITY DURING THE
AFTERNOON.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A COLD FRONT OVER CNTRL NY AND PA WILL PASS THIS EVE. LOW PRES WILL
DEVELOP ALONG THE FRONT AND PASS E OF THE AREA OVERNIGHT.
CONDITIONS IMPROVING THIS AFTN...ESPECIALLY WRN METRO. JFK/LGA WILL
STILL HAVE ONSHORE COMPONENT SO TAFS INDICATE LWR CIGS WITH VSBY
RESTRICTIONS POSSIBLE KJFK. VFR FCST FOR KEWR AND KTEB.
SOME -SHRA POSSIBLE AHEAD OF THE FRONT THIS EVE.
AREA WILL BE ALONG THE RAIN GRADIENT OVERNIGHT. THIS RESULTS IN A
LOW CONFIDENCE FCST. TAFS INDICATE BEST CHANCES FOR IFR KISP-KHPN
AND POINTS E. THERE IS THE POTENTIAL FOR THIS TO EXPAND WWD ALL THE
WAY TO KEWR DEPENDING ON THE DEVELOPMENT OF LOW PRES.
IMPROVEMENT FROM THE W AFT 10Z THU. VFR IN THE METRO 14Z THU AND
BEYOND.
S TO SSW WINDS TODAY. SPEEDS GENERALLY AOB 10KT. COLD FRONT BRINGS A
WIND SHIFT THE NW TNGT BUT SPEEDS BLW 15 KT EXPECTED. NW WINDS
INCREASE THU. SPEEDS 15-20KT WITH PEAK GUSTS TO 30KT POSSIBLE.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: TIMING OF IMPROVEMENT UNCERTAIN FOR THIS AFTN.
AMENDMENTS POSSIBLE FOR CIGS/VSBY THRU THE TAF PERIOD.
KLGA FCSTER COMMENTS: AMENDMENTS LIKELY FOR CIGS/VSBY THRU THE TAF
PERIOD.
KEWR FCSTER COMMENTS: AMENDMENTS POSSIBLE FOR CIGS/VSBY THRU THE TAF
PERIOD.
KTEB FCSTER COMMENTS: AMENDMENTS POSSIBLE FOR CIGS/VSBY THRU THE TAF
PERIOD.
KHPN FCSTER COMMENTS: CONFIDENCE LOW IN TIMING OF IMPROVEMENT THIS
AFTN. AMENDMENTS LIKELY.
KISP FCSTER COMMENTS: SOME IMPROVEMENT IS POSSIBLE THIS AFTN BUT
CONFIDENCE IS LOW.
OUTLOOK FOR 18Z THU THROUGH MON...
THU AFTN...CLEARING TO VFR ACROSS ERN TERMINALS. VFR ELSEWHERE.
STRONG NW WINDS.
THU NGT...VFR WITH DIMINISHING NW WINDS.
FRI-SUN...VFR.
MON...MVFR POSSIBLE.
&&
.MARINE...
WAVEWATCH IS RUNNING ABOUT 2 FEET TOO HIGH AT THIS TIME. LOW
LEVEL JET IS NOW JUST EAST OF THE WATERS...AND PRESSURE GRADIENT
TIGHTENS ONLY A LITTLE OVER THE EASTERN WATERS. SOME SWELL IS
BEING GENERATED...AND PROBABLY MAINTAINED THROUGH THURSDAY AS A
WEAK COASTAL LOW DEVELOPS IN THE VICINITY TONIGHT AND HEADS
NORTHEAST. THEREFORE EXPECTING SEAS OF 3 TO 6 FT THROUGH
TODAY...INCREASING ABOUT A FOOT LATE TONIGHT INTO THURSDAY.
OVER THE REMAINDER OF THE WATERS...EXPECT WINDS TO REMAIN BELOW
SCA LEVELS THROUGH THURSDAY...THOUGH OCCASIONAL GUSTS TO 25 KT ARE
POSSIBLE THURSDAY AFTERNOON.
WAVES WILL DIMINISH THURSDAY NIGHT AND DROP BELOW SCA CRITERIA BY
LATE FRIDAY MORNING INTO EARLY FRIDAY AFTERNOON. SUSTAINED WINDS
WILL ALSO DIMINISH THURSDAY NIGHT INTO FRIDAY MORNING AS LOW
PRESSURE DEPARTS AND GRADIENT WEAKENS. HOWEVER...WIND GUSTS TO 25
KT ARE POSSIBLE BOTH PERIODS. A PERIOD OF TRANQUIL WEATHER IS
EXPECTED OVER THE WATERS AS HIGH PRESSURE BUILDS IN FRIDAY NIGHT
INTO SUNDAY MORNING. SEAS ONCE AGAIN BUILD TOWARDS 5 FT ON SUNDAY
WITH STRENGTHENING SOUTHWEST FLOW OUT AHEAD OF AN APPROACHING
COLD FRONT.
&&
.HYDROLOGY...
STORM TOTAL PRECIPITATION WITH THIS SYSTEM IS EXPECTED TO RANGE
FROM A 1/2 AN INCH TO AN INCH FROM NYC ON N AND W AND FROM 1 TO
AROUND 2 1/4 INCHES ACROSS LONG ISLAND AND SOUTHERN CT...WITH
HIGHEST AMOUNTS EXPECTED OVER THE TWIN FORKS AND COASTAL SE CT.
LOCALLY HIGHER AMOUNTS ARE POSSIBLE...ESPECIALLY UNDER ANY
STRONGER CONVECTION. THE MAIN THREAT IS FOR MINOR URBAN/POOR
DRAINAGE FLOODING.
&&
.TIDES/COASTAL FLOODING...
TIDE LEVELS FELL SHORT OF MINOR FLOODING BENCHMARKS BY AROUND TWO
TENTHS OF A FOOT ON AVERAGE LAST NIGHT. THE PREDICTED TIDES WILL BE
A FEW OF TENTHS OF A FOOT LOWER WITH TONIGHT`S HIGH TIDE CYCLE...AND
TIDAL PILING DOES NOT APPEAR TO BE MUCH OF AN ADVERSE FACTOR BASED
ON FORECAST WINDS AND LATEST GAGE OBS. THEREFORE...EXPECTING
TONIGHT`S HIGH TIDE CYCLE TO FALL SAFELY BELOW MINOR FLOODING
THRESHOLDS AND WILL NOT ISSUE ANY STATEMENTS AT THIS TIME.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THURSDAY FOR ANZ350-353-
355.
&&
$$
SYNOPSIS...JC/MALOIT/JP
NEAR TERM...JC/MALOIT
SHORT TERM...MALOIT
LONG TERM...JP
AVIATION...12
MARINE...JC/MALOIT
HYDROLOGY...MALOIT
TIDES/COASTAL FLOODING...JC
AREA FORECAST DISCUSSION
NWS NEW YORK NY
125 PM EDT WED MAY 9 2012
.SYNOPSIS...
A WARM FRONT CONTINUE TO HEAD NORTH OF THE TRI-STATE AREA THIS
MORNING...WITH A COLD FRONT MOVING INTO WESTERN PARTS OF THE
REGION BY LATE THIS AFTERNOON. AN AREA OF LOW PRESSURE WILL FORM
ALONG THE MID ATLANTIC COAST ALONG THE FRONT THIS EVENING...THEN
SLOWLY TRACK NORTHEAST ALONG THE FRONT INTO THE GULF OF MAINE BY
THURSDAY AFTERNOON...AND INTO THE WESTERN CANADIAN MARITIME
PROVINCES INTO THURSDAY NIGHT. A COLD FRONT MOVES THROUGH ON
FRIDAY. HIGH PRESSURE BUILDS IN FOR SATURDAY. A COLD FRONT
APPROACHES ON SUNDAY. IT WILL REMAIN UNSETTLED THROUGH THE MIDDLE
OF NEXT WEEK AS THE FRONT BECOMES STATIONARY AND DISTURBANCES RIDE
ALONG IT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MINOR ADJUSTMENTS WITH THIS UPDATE. POPS STILL HIGHER OVERALL OVER
EASTERN SECTIONS OF THE FORECAST AREA. FAR WESTERN ZONES COULD SEE
AN INCREASE IN SHOWER COVERAGE THIS AFTERNOON WITH DESTABILIZATION
AND A COLD FRONT NEARBY. A FEW MODELS...INCLUDING THE HRRR SHOW
THIS. SBCAPES ACCORDING TO LAPS DATA OVER THE WESTERN ZONES ARE
ALREADY UP TO AROUND 500 J/KG. THUNDERSTORMS THEREFORE POSSIBLE
THERE...AND WITH WET BULB ZERO HEIGHTS NEAR 8-9KFT...SMALL HAIL
NOT OUT OF THE QUESTION EITHER ASIDE FROM A STRONG GUST OR TWO.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
BASED ON MODEL SOUNDINGS...APPEARS THAT INSTABILITY SHOULD LAST
INTO THE FIRST PART OF THE EVENING...SO HAVE CARRIED A CHANCE OF
THUNDER THROUGH 00Z. OTHERWISE...THE NEXT ROUND OF HEAVIER
RAINFALL ARRIVES FOR THE SE 1/2 OF THE CWA TONIGHT IN RESPONSE TO
INCREASED FRONTOGENETIC AND DYNAMIC FORCING ASSOCIATED WITH THE
COASTAL LOW PASSING TO THE SE. THE NW 1/2 OF THE CWA SHOULD SEE
SCATTERED TO NUMEROUS SHOWERS DUE TO FORCING FROM AN APPROACHING
500 HPA TROUGH AND BEING IN THE RIGHT REAR QUADRANT OF A 120+ KT
300 HPA JET...ONCE AGAIN CHANCE POPS NW TO CATEGORICAL POPS SE.
FOR LOWS USED A BLEND OF 1/2 BIAS CORRECTED MAV GUIDANCE AND 1/4
EACH OF MET GUIDANCE AND NAM 2-METER TEMPERATURES. THIS YIELDED
VALUES AROUND 5 DEGREES ABOVE NORMAL.
PRECIPITATION SHOULD BEGIN TO SLOWLY TAPER OFF FROM NW TO SE FROM
LATE TONIGHT INTO THURSDAY MORNING AS THE COASTAL LOW AND
ASSOCIATED COLD FRONT PASS TO OUR EAST. BY THURSDAY AFTERNOON HAVE
MAINLY SLIGHT CHANCE POPS - CHANCE ACROSS THE WESTERN PORTION OF
THE NORTHERN INTERIOR ZONES...FOR INSTABILITY SHOWERS IN RESPONSE
TO THE 500 HPA TROUGH BUILDING INTO THE REGION. FOR HIGHS USED A
BLEND OF 30 PERCENT EACH OF MIXING DOWN FROM 825 HPA AND MAV AND
MET GUIDANCE AND 10 PERCENT NAM 2-METER TEMPERATURES. THIS
YIELDED TEMPERATURES AROUND NORMAL.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
SURFACE LOW PRESSURE CONTINUES TO MOVE AWAY FROM THE AREA THURSDAY
NIGHT...WHILE AN UPPER LEVEL TROUGH MOVES THROUGH. COLD FRONT MOVES
THROUGH DURING THE DAY ON FRIDAY...BUT NOT A LOT OF MOISTURE TO WORK
WITH AS A DRY WESTERLY FLOW WILL SHIFT TO THE NORTHWEST BEHIND THE
FRONT.
HIGH PRESSURE BUILDS IN FOR SATURDAY AND THE FIRST HALF OF SUNDAY.
RIDGING ALOFT BEGINS SATURDAY NIGHT INTO SUNDAY. SO HIGHS ON SUNDAY
SHOULD BE A COUPLE OF DEGREES WARMER THAN SATURDAY FOR INLAND
SECTIONS. TROUGH WILL DIG IN THE MIDDLE OF THE US ON
SUNDAY...PUSHING A COLD FRONT TOWARD THE EAST COAST. GFS DEVELOPS AN
OMEGA TYPE BLOCKING PATTERN DEVELOPS OVER THE WESTERN ATLANTIC AS
AN UPPER LEVEL LOW BECOMES CLOSED OFF OVER THE CENTRAL PLAINS LATE
MONDAY INTO TUESDAY. THIS MEANS AN EXTENDED PERIOD OF UNSETTLED
WEATHER AS THE COLD FRONT BECOMES STATIONARY NEAR THE REGION AND
DISTURBANCES RIDE ALONG THE BOUNDARY. THE ECMWF DOES NOT CUT OFF THE
LOW UNTIL WEDNESDAY NIGHT...SO THIS LENDS TO SOME MODEL DIFFERENCES
IN THE LONG TERM...BUT IT ALSO DEVELOPS THE OMEGA BLOCK.
CLIMATOLOGICALLY SPEAKING...SPRING IS THE TIME FOR BLOCKING
PATTERNS...SO WILL CARRY POPS THROUGH THE END OF THE LONG TERM
PERIOD. LIFTED INDICES BELOW 0 SUNDAY AFTERNOON...SO ADDED SLIGHT
CHANCE OF THUNDER FOR SOUTHWESTERN CT...LOWER HUDSON
VALLEY...NORTHEAST NJ...AND PORTIONS OF NEW YORK CITY DURING THE
AFTERNOON.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A COLD FRONT OVER WRN NY AND PA WILL PASS THIS EVE. LOW PRES WILL
DEVELOP ALONG THE FRONT AND PASS E OF THE AREA OVERNIGHT.
MVFR OR LWR THRU THE TAF PERIOD. CIGS BLW 1K FT REMAIN ENTRENCHED
ACROSS THE REGION AT 1430Z. HAVE EXTENDED THE IFR TIL AT LEAST 17Z
ACROSS THE ENTIRE AREA. LLVL MOISTURE MAY BE TRAPPED IN THE
METRO DUE TO A WEAK SFC TROF OVER THE AREA...SO CONFIDENCE IN THE
TIMING OF ANY IMPROVEMENT TODAY IS LOW. ERN ARPTS WILL CONTINUE TO
SEE RA THRU 18Z.
NEXT ROUND OF PCPN LATE THIS AFTN. MAY BE MORE SHOWERY IN NATURE
WITH THE THREAT OF AN ISOLD TSTM TIL LOW PRES DEEPENS E OF KACY
TNGT. STEADIER RAIN AFT THAT ESPECIALLY KISP/KGON.
S TO SSW WINDS TODAY. SPEEDS GENERALLY AOB 10KT. COLD FRONT BRINGS
A WIND SHIFT THE NW TNGT BUT SPEEDS BLW 15 KT EXPECTED ATTM.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: CIGS MAY DROP TO AROUND 500 FT AT TIMES THRU
17Z. AMENDMENTS LIKELY TODAY WITH CONFIDENCE LOW IN TIMING OF
ANY IMPROVEMENT.
KLGA FCSTER COMMENTS: CIGS MAY DROP TO AROUND 500 FT AT TIMES THRU
17Z. AMENDMENTS LIKELY TODAY WITH CONFIDENCE LOW IN TIMING OF
ANY IMPROVEMENT.
KEWR FCSTER COMMENTS: AMENDMENTS LIKELY TODAY WITH CONFIDENCE LOW
IN TIMING OF ANY IMPROVEMENT.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: AMENDMENTS LIKELY TODAY WITH CONFIDENCE LOW
IN TIMING OF ANY IMPROVEMENT.
KHPN FCSTER COMMENTS: VSBY EXPECTED TO IMPROVE TO 2SM SO HAS BEEN
INDICATED IN THE AMD TAF. AMENDMENTS LIKELY TODAY WITH CONFIDENCE
LOW IN TIMING OF ANY IMPROVEMENT.
KISP FCSTER COMMENTS: AMENDMENTS LIKELY TODAY WITH CONFIDENCE
LOW IN TIMING OF ANY IMPROVEMENT.
OUTLOOK FOR 12Z THU THROUGH SUN...
THURSDAY...VFR. SCATTERED SHOWERS POSSIBLE EARLY.
THURSDAY NIGHT-SUNDAY...VFR. SHOWERS POSSIBLE SUNDAY.
&&
.MARINE...
WAVEWATCH IS RUNNING ABOUT 2 FEET TOO HIGH AT THIS TIME. LOW
LEVEL JET IS NOW JUST EAST OF THE WATERS...AND PRESSURE GRADIENT
TIGHTENS ONLY A LITTLE OVER THE EASTERN WATERS. SOME SWELL IS
BEING GENERATED...AND PROBABLY MAINTAINED THROUGH THURSDAY AS A
WEAK COASTAL LOW DEVELOPS IN THE VICINITY TONIGHT AND HEADS
NORTHEAST. THEREFORE EXPECTING SEAS OF 3 TO 6 FT THROUGH
TODAY...INCREASING ABOUT A FOOT LATE TONIGHT INTO THURSDAY.
OVER THE REMAINDER OF THE WATERS...EXPECT WINDS TO REMAIN BELOW
SCA LEVELS THROUGH THURSDAY...THOUGH OCCASIONAL GUSTS TO 25 KT ARE
POSSIBLE THURSDAY AFTERNOON.
WAVES WILL DIMINISH THURSDAY NIGHT AND DROP BELOW SCA CRITERIA BY
LATE FRIDAY MORNING INTO EARLY FRIDAY AFTERNOON. SUSTAINED WINDS
WILL ALSO DIMINISH THURSDAY NIGHT INTO FRIDAY MORNING AS LOW
PRESSURE DEPARTS AND GRADIENT WEAKENS. HOWEVER...WIND GUSTS TO 25
KT ARE POSSIBLE BOTH PERIODS. A PERIOD OF TRANQUIL WEATHER IS
EXPECTED OVER THE WATERS AS HIGH PRESSURE BUILDS IN FRIDAY NIGHT
INTO SUNDAY MORNING. SEAS ONCE AGAIN BUILD TOWARDS 5 FT ON SUNDAY
WITH STRENGTHENING SOUTHWEST FLOW OUT AHEAD OF AN APPROACHING
COLD FRONT.
&&
.HYDROLOGY...
STORM TOTAL PRECIPITATION WITH THIS SYSTEM IS EXPECTED TO RANGE
FROM A 1/2 AN INCH TO AN INCH FROM NYC ON N AND W AND FROM 1 TO
AROUND 2 1/4 INCHES ACROSS LONG ISLAND AND SOUTHERN CT...WITH
HIGHEST AMOUNTS EXPECTED OVER THE TWIN FORKS AND COASTAL SE CT.
LOCALLY HIGHER AMOUNTS ARE POSSIBLE...ESPECIALLY UNDER ANY
STRONGER CONVECTION. THE MAIN THREAT IS FOR MINOR URBAN/POOR
DRAINAGE FLOODING.
&&
.TIDES/COASTAL FLOODING...
TIDE LEVELS FELL SHORT OF MINOR FLOODING BENCHMARKS BY AROUND TWO
TENTHS OF A FOOT ON AVERAGE LAST NIGHT. THE PREDICTED TIDES WILL BE
A FEW OF TENTHS OF A FOOT LOWER WITH TONIGHT`S HIGH TIDE CYCLE...AND
TIDAL PILING DOES NOT APPEAR TO BE MUCH OF AN ADVERSE FACTOR BASED
ON FORECAST WINDS AND LATEST GAGE OBS. THEREFORE...EXPECTING
TONIGHT`S HIGH TIDE CYCLE TO FALL SAFELY BELOW MINOR FLOODING
THRESHOLDS AND WILL NOT ISSUE ANY STATEMENTS AT THIS TIME.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THURSDAY FOR ANZ350-353-
355.
&&
$$
SYNOPSIS...JC/MALOIT/JP
NEAR TERM...JC/MALOIT
SHORT TERM...MALOIT
LONG TERM...JP
AVIATION...12
MARINE...JC/MALOIT
HYDROLOGY...MALOIT
TIDES/COASTAL FLOODING...JC
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
658 PM EDT WED MAY 9 2012
.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 316 PM EDT WED MAY 9 2012
AN UPPER TROUGH MOVING THROUGH THE AREA WILL KEEP LOW CHANCES FOR
SHOWERS IN THE FORECAST THIS EVENING...BUT BY LATER TONIGHT HIGH
PRESSURE WILL START BUILDING IN AND DRY THINGS OUT THROUGH THE END
OF THE WEEK AND INTO THE WEEKEND. TEMPERATURES WILL CLIMB BACK INTO
THE 70S BY FRIDAY. SATURDAY NIGHT A FRONT WILL APPROACH THE AREA
FROM THE NORTHWEST AND COULD STALL NEAR CENTRAL INDIANA KEEPING
CHANCES FOR THUNDERSTORMS IN THE FORECAST FROM SATURDAY NIGHT
THROUGH MONDAY.
&&
.NEAR TERM /THIS EVENING AND TONIGHT/...
ISSUED AT 316 PM EDT WED MAY 9 2012
FORECAST FOCUS IS ON CHANCES FOR RAIN THIS EVENING INTO EARLY
TONIGHT. RELIED MAINLY ON OBSERVATIONAL TRENDS AND HRRR FOR THE
FIRST 6-8 HOURS...AFTER THAT MODELS ARE IN GOOD AGREEMENT ON DRY
WEATHER...MOSTLY CLEAR TO CLEAR SKIES AND THUS GOOD RADIATIONAL
COOLING FOR LOWS IN THE UPPER 30S TO LOWER 40S SIMILAR TO A MAV/MET
BLEND.
FOR POPS...SOME WEAK RADAR ECHOES ARE SHOWING UP ACROSS THE NORTHERN
COUNTIES WITH MORE /AND SLIGHTLY STRONGER/ ECHOES IN NORTHEAST
ILLINOIS AND NORTHWEST INDIANA. RAPID REFRESH IS DEPICTING THIS
FAIRLY WELL AND SHOWS THESE ECHOES HOLDING TOGETHER AND CONTINUING
TO MOVE SOUTHEAST. THUS INCREASED TO CHANCE POPS ACROSS THE NORTH
AND EAST AND USED SCATTERED SHOWERS WORDING. HAVE ONLY SEEN ONE
STRIKE OF LIGHTNING WITH THE MOST INTENSE CELL IN NORTHWEST ILLINOIS
SO DO NOT THINK THERE IS A NEED TO ADD THUNDER AT THIS TIME. FURTHER
SOUTHWEST USED JUST A SCATTERED SPRINKLES AS IT LOOKS LIKE THE
BETTER ECHOES WILL STAY EAST OF THERE WITH THE UPPER TROUGH AXIS.
MAINTAINED A SLIGHT CHANCE FOR SPRINKLES IN THE SOUTHEAST FROM 0-2Z
AS IT COULD TAKE A LITTLE LONGER FOR THIS DIURNALLY DRIVEN
PRECIPITATION TO COME TO AN END.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
ISSUED AT 316 PM EDT WED MAY 9 2012
FORECAST FOCUS IS ON TEMPERATURES. MODELS ARE IN GOOD AGREEMENT AND
WILL USE A CONSENSUS APPROACH. HIGH PRESSURE WILL MOVE ACROSS
CENTRAL INDIANA THROUGH THE SHORT TERM. SKIES WILL BE CLEAR TO
MOSTLY CLEAR THROUGH MUCH OF THE PERIOD. MOS VALUES FROM MAV AND MET
WERE VERY CLOSE AND USED AN AVERAGE FOR HIGHS STARTING IN THE UPPER
60S TO LOW 70S THURSDAY AND CLIMBING TO THE MID 70S ON FRIDAY AND
SATURDAY. BY FRIDAY NIGHT/SATURDAY A FRONT WILL APPROACH FROM THE
WEST...BUT HIGH PRESSURE AT THE SURFACE AND UPPER RIDGING ALOFT
SHOULD KEEP THIS FEATURE FROM REACHING THE AREA UNTIL AT LEAST
SATURDAY EVENING. THUS LEFT DRY POPS GOING BUT DID INCREASE CLOUD
COVER ON SATURDAY. LOW TEMPERATURES SHOULD DROP PRETTY QUICKLY AT
NIGHT WITH LITTLE TO NOTHING IN THE WAY OF CLOUD COVER BUT WILL SEE
SOME WARM ADVECTION TO INCREASE TEMPERATURES A LITTLE THURSDAY /IN
THE 40S/ AND FRIDAY NIGHTS /UPPER 40S TO LOW 50S/.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ISSUED AT 316 PM EDT WED MAY 9 2012
LOOKS LIKE A WET START TO THE EXTENDED...AS THE PERIOD BEGINS WITH
AN APPROACHING COLD FRONT TO THE NORTH ASSOCIATED WITH AN UPPER
TROUGH ACROSS THE GREAT LAKES. ALSO...A WEAK DISTURBANCE IS PROGGED
TO MOVE NORTHEAST FROM THE MID-MISSISSIPPI VALLEY INTO THE OHIO
RIVER VALLEY SATURDAY NIGHT AND SUNDAY...BRINGING ADDITIONAL
MOISTURE TO THE AREA. ECMWF/GFS ARE IN FAIRLY GOOD AGREEMENT EARLY
ON IN THE EXTENDED TIMEFRAME. HOWEVER...BY 12Z MON THE GFS
PROGRESSES THE UPPER TROUGH THROUGH THE FORECAST AREA QUICKER THAN
THE ECMWF. THEREFORE...DECIDED TO HOLD ON TO SOME LOW CHANCE POP ON
MONDAY THOUGH CONFIDENCE IS LOW THIS WILL OCCUR. THE REMAINDER OF
THE PERIOD APPEARS DRY AS HIGH PRESSURE FILTERS IN. STUCK CLOSE TO
ALLBLEND FOR TEMPS AS THEY LOOK REASONABLE.
&&
.AVIATION /DISCUSSION FOR THE 100000Z TAF ISSUANCE/...
ISSUED AT 658 PM EDT WED MAY 9 2012
VFR THROUGH THE TAF PERIOD.
AN UPPER TROUGH CURRENTLY ACROSS OUR REGION WILL MOVE ON TO THE EAST
AND WITH LOSS OF DAYTIME HEATING SKIES SHOULD BECOME CLEAR BY
MIDNIGHT. WINDS WILL ALSO BECOME 6 KNOTS OR LESS OVERNIGHT.
ON THURSDAY QUIET WEATHER WILL BE THE RULE AS HIGH PRESSURE MOVES
EAST ACROSS THE MID MISSISSIPPI VALLEY AND MOVING TO INDIANA BY
THURSDAY NIGHT. THERE MAY BE A FEW CU BY MIDDAY THURSDAY. WINDS
WILL BE FROM THE NORTHWEST THURSDAY AROUND 7 TO 10 KNOTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP
SHORT TERM...CP
LONG TERM....MRD/CP
AVIATION...JH
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
428 PM EDT WED MAY 9 2012
.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 316 PM EDT WED MAY 9 2012
AN UPPER TROUGH MOVING THROUGH THE AREA WILL KEEP LOW CHANCES FOR
SHOWERS IN THE FORECAST THIS EVENING...BUT BY LATER TONIGHT HIGH
PRESSURE WILL START BUILDING IN AND DRY THINGS OUT THROUGH THE END
OF THE WEEK AND INTO THE WEEKEND. TEMPERATURES WILL CLIMB BACK INTO
THE 70S BY FRIDAY. SATURDAY NIGHT A FRONT WILL APPROACH THE AREA
FROM THE NORTHWEST AND COULD STALL NEAR CENTRAL INDIANA KEEPING
CHANCES FOR THUNDERSTORMS IN THE FORECAST FROM SATURDAY NIGHT
THROUGH MONDAY.
&&
.NEAR TERM /THIS EVENING AND TONIGHT/...
ISSUED AT 316 PM EDT WED MAY 9 2012
FORECAST FOCUS IS ON CHANCES FOR RAIN THIS EVENING INTO EARLY
TONIGHT. RELIED MAINLY ON OBSERVATIONAL TRENDS AND HRRR FOR THE
FIRST 6-8 HOURS...AFTER THAT MODELS ARE IN GOOD AGREEMENT ON DRY
WEATHER...MOSTLY CLEAR TO CLEAR SKIES AND THUS GOOD RADIATIONAL
COOLING FOR LOWS IN THE UPPER 30S TO LOWER 40S SIMILAR TO A MAV/MET
BLEND.
FOR POPS...SOME WEAK RADAR ECHOES ARE SHOWING UP ACROSS THE NORTHERN
COUNTIES WITH MORE /AND SLIGHTLY STRONGER/ ECHOES IN NORTHEAST
ILLINOIS AND NORTHWEST INDIANA. RAPID REFRESH IS DEPICTING THIS
FAIRLY WELL AND SHOWS THESE ECHOES HOLDING TOGETHER AND CONTINUING
TO MOVE SOUTHEAST. THUS INCREASED TO CHANCE POPS ACROSS THE NORTH
AND EAST AND USED SCATTERED SHOWERS WORDING. HAVE ONLY SEEN ONE
STRIKE OF LIGHTNING WITH THE MOST INTENSE CELL IN NORTHWEST ILLINOIS
SO DO NOT THINK THERE IS A NEED TO ADD THUNDER AT THIS TIME. FURTHER
SOUTHWEST USED JUST A SCATTERED SPRINKLES AS IT LOOKS LIKE THE
BETTER ECHOES WILL STAY EAST OF THERE WITH THE UPPER TROUGH AXIS.
MAINTAINED A SLIGHT CHANCE FOR SPRINKLES IN THE SOUTHEAST FROM 0-2Z
AS IT COULD TAKE A LITTLE LONGER FOR THIS DIURNALLY DRIVEN
PRECIPITATION TO COME TO AN END.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
ISSUED AT 316 PM EDT WED MAY 9 2012
FORECAST FOCUS IS ON TEMPERATURES. MODELS ARE IN GOOD AGREEMENT AND
WILL USE A CONSENSUS APPROACH. HIGH PRESSURE WILL MOVE ACROSS
CENTRAL INDIANA THROUGH THE SHORT TERM. SKIES WILL BE CLEAR TO
MOSTLY CLEAR THROUGH MUCH OF THE PERIOD. MOS VALUES FROM MAV AND MET
WERE VERY CLOSE AND USED AN AVERAGE FOR HIGHS STARTING IN THE UPPER
60S TO LOW 70S THURSDAY AND CLIMBING TO THE MID 70S ON FRIDAY AND
SATURDAY. BY FRIDAY NIGHT/SATURDAY A FRONT WILL APPROACH FROM THE
WEST...BUT HIGH PRESSURE AT THE SURFACE AND UPPER RIDGING ALOFT
SHOULD KEEP THIS FEATURE FROM REACHING THE AREA UNTIL AT LEAST
SATURDAY EVENING. THUS LEFT DRY POPS GOING BUT DID INCREASE CLOUD
COVER ON SATURDAY. LOW TEMPERATURES SHOULD DROP PRETTY QUICKLY AT
NIGHT WITH LITTLE TO NOTHING IN THE WAY OF CLOUD COVER BUT WILL SEE
SOME WARM ADVECTION TO INCREASE TEMPERATURES A LITTLE THURSDAY /IN
THE 40S/ AND FRIDAY NIGHTS /UPPER 40S TO LOW 50S/.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ISSUED AT 316 PM EDT WED MAY 9 2012
LOOKS LIKE A WET START TO THE EXTENDED...AS THE PERIOD BEGINS WITH
AN APPROACHING COLD FRONT TO THE NORTH ASSOCIATED WITH AN UPPER
TROUGH ACROSS THE GREAT LAKES. ALSO...A WEAK DISTURBANCE IS PROGGED
TO MOVE NORTHEAST FROM THE MID-MISSISSIPPI VALLEY INTO THE OHIO
RIVER VALLEY SATURDAY NIGHT AND SUNDAY...BRINGING ADDITIONAL
MOISTURE TO THE AREA. ECMWF/GFS ARE IN FAIRLY GOOD AGREEMENT EARLY
ON IN THE EXTENDED TIMEFRAME. HOWEVER...BY 12Z MON THE GFS
PROGRESSES THE UPPER TROUGH THROUGH THE FORECAST AREA QUICKER THAN
THE ECMWF. THEREFORE...DECIDED TO HOLD ON TO SOME LOW CHANCE POP ON
MONDAY THOUGH CONFIDENCE IS LOW THIS WILL OCCUR. THE REMAINDER OF
THE PERIOD APPEARS DRY AS HIGH PRESSURE FILTERS IN. STUCK CLOSE TO
ALLBLEND FOR TEMPS AS THEY LOOK REASONABLE.
&&
.AVIATION /DISCUSSION FOR THE 092100Z KIND TAF UPDATE/...
ISSUED AT 428 PM EDT WED MAY 9 2012
MINOR TWEAKS MADE TO KIND TAF PER OBSERVATIONS. OTHERWISE...NO OTHER
CHANGES NEEDED AT THIS TIME. PREVIOUS AVIATION DISCUSSION FOLLOWS...
VFR CONDITIONS EXPECTED TO PREVAIL THROUGH THIS TAF PERIOD...
A WEAK UPPER LEVEL TROUGH IS CURRENTLY MAKING IT/S WAY THROUGH
CENTRAL INDIANA AND SHOULD PUSH EAST OF THE REGION TONIGHT. FORECAST
SOUNDINGS INDICATE A DRY COLUMN...HOWEVER CONVECTIVE TEMPERATURES
HAVE BEEN REACHED IN MANY LOCATION ALREADY...PRODUCING SCT-BKN CU.
WITH CCL/S NEAR 4000 FT...ANY CIGS WILL BE VFR. A FEW WIDELY
SCATTERED SPRINKLES ARE POSSIBLY THIS AFTERNOON...PER THE RAPID
REFRESH BUT DO NOT FEEL CONFIDENT ENOUGH TO MENTION VCSH AT THIS
TIME...AND IN EITHER CASE THIS SHOULD NOT HAVE AN IMPACT OF THE
FLIGHT CATEGORY. AS HEATING IS LOST AFTER SUNSET...CU WILL
DISSIPATE LEADING TO CLEAR SKIES. SUBSIDENCE WILL CONTINUE
OVERNIGHT AND WITH DEW POINTS EXPECTED IN THE UPPER 30S...FOG IS
NOT ANTICIPATED.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP
SHORT TERM...CP
LONG TERM....MRD/CP
AVIATION...SMF/JH
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
321 PM EDT WED MAY 9 2012
.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM
AND LONG TERM SECTIONS HAVE BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 316 PM EDT WED MAY 9 2012
AN UPPER TROUGH MOVING THROUGH THE AREA WILL KEEP LOW CHANCES FOR
SHOWERS IN THE FORECAST THIS EVENING...BUT BY LATER TONIGHT HIGH
PRESSURE WILL START BUILDING IN AND DRY THINGS OUT THROUGH THE END
OF THE WEEK AND INTO THE WEEKEND. TEMPERATURES WILL CLIMB BACK INTO
THE 70S BY FRIDAY. SATURDAY NIGHT A FRONT WILL APPROACH THE AREA
FROM THE NORTHWEST AND COULD STALL NEAR CENTRAL INDIANA KEEPING
CHANCES FOR THUNDERSTORMS IN THE FORECAST FROM SATURDAY NIGHT
THROUGH MONDAY.
&&
.NEAR TERM /THIS EVENING AND TONIGHT/...
ISSUED AT 316 PM EDT WED MAY 9 2012
FORECAST FOCUS IS ON CHANCES FOR RAIN THIS EVENING INTO EARLY
TONIGHT. RELIED MAINLY ON OBSERVATIONAL TRENDS AND HRRR FOR THE
FIRST 6-8 HOURS...AFTER THAT MODELS ARE IN GOOD AGREEMENT ON DRY
WEATHER...MOSTLY CLEAR TO CLEAR SKIES AND THUS GOOD RADIATIONAL
COOLING FOR LOWS IN THE UPPER 30S TO LOWER 40S SIMILAR TO A MAV/MET
BLEND.
FOR POPS...SOME WEAK RADAR ECHOES ARE SHOWING UP ACROSS THE NORTHERN
COUNTIES WITH MORE /AND SLIGHTLY STRONGER/ ECHOES IN NORTHEAST
ILLINOIS AND NORTHWEST INDIANA. RAPID REFRESH IS DEPICTING THIS
FAIRLY WELL AND SHOWS THESE ECHOES HOLDING TOGETHER AND CONTINUING
TO MOVE SOUTHEAST. THUS INCREASED TO CHANCE POPS ACROSS THE NORTH
AND EAST AND USED SCATTERED SHOWERS WORDING. HAVE ONLY SEEN ONE
STRIKE OF LIGHTNING WITH THE MOST INTENSE CELL IN NORTHWEST ILLINOIS
SO DO NOT THINK THERE IS A NEED TO ADD THUNDER AT THIS TIME. FURTHER
SOUTHWEST USED JUST A SCATTERED SPRINKLES AS IT LOOKS LIKE THE
BETTER ECHOES WILL STAY EAST OF THERE WITH THE UPPER TROUGH AXIS.
MAINTAINED A SLIGHT CHANCE FOR SPRINKLES IN THE SOUTHEAST FROM 0-2Z
AS IT COULD TAKE A LITTLE LONGER FOR THIS DIURNALLY DRIVEN
PRECIPITATION TO COME TO AN END.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
ISSUED AT 316 PM EDT WED MAY 9 2012
FORECAST FOCUS IS ON TEMPERATURES. MODELS ARE IN GOOD AGREEMENT AND
WILL USE A CONSENSUS APPROACH. HIGH PRESSURE WILL MOVE ACROSS
CENTRAL INDIANA THROUGH THE SHORT TERM. SKIES WILL BE CLEAR TO
MOSTLY CLEAR THROUGH MUCH OF THE PERIOD. MOS VALUES FROM MAV AND MET
WERE VERY CLOSE AND USED AN AVERAGE FOR HIGHS STARTING IN THE UPPER
60S TO LOW 70S THURSDAY AND CLIMBING TO THE MID 70S ON FRIDAY AND
SATURDAY. BY FRIDAY NIGHT/SATURDAY A FRONT WILL APPROACH FROM THE
WEST...BUT HIGH PRESSURE AT THE SURFACE AND UPPER RIDGING ALOFT
SHOULD KEEP THIS FEATURE FROM REACHING THE AREA UNTIL AT LEAST
SATURDAY EVENING. THUS LEFT DRY POPS GOING BUT DID INCREASE CLOUD
COVER ON SATURDAY. LOW TEMPERATURES SHOULD DROP PRETTY QUICKLY AT
NIGHT WITH LITTLE TO NOTHING IN THE WAY OF CLOUD COVER BUT WILL SEE
SOME WARM ADVECTION TO INCREASE TEMPERATURES A LITTLE THURSDAY /IN
THE 40S/ AND FRIDAY NIGHTS /UPPER 40S TO LOW 50S/.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ISSUED AT 316 PM EDT WED MAY 9 2012
LOOKS LIKE A WET START TO THE EXTENDED...AS THE PERIOD BEGINS WITH
AN APPROACHING COLD FRONT TO THE NORTH ASSOCIATED WITH AN UPPER
TROUGH ACROSS THE GREAT LAKES. ALSO...A WEAK DISTURBANCE IS PROGGED
TO MOVE NORTHEAST FROM THE MID-MISSISSIPPI VALLEY INTO THE OHIO
RIVER VALLEY SATURDAY NIGHT AND SUNDAY...BRINGING ADDITIONAL
MOISTURE TO THE AREA. ECMWF/GFS ARE IN FAIRLY GOOD AGREEMENT EARLY
ON IN THE EXTENDED TIMEFRAME. HOWEVER...BY 12Z MON THE GFS
PROGRESSES THE UPPER TROUGH THROUGH THE FORECAST AREA QUICKER THAN
THE ECMWF. THEREFORE...DECIDED TO HOLD ON TO SOME LOW CHANCE POP ON
MONDAY THOUGH CONFIDENCE IS LOW THIS WILL OCCUR. THE REMAINDER OF
THE PERIOD APPEARS DRY AS HIGH PRESSURE FILTERS IN. STUCK CLOSE TO
ALLBLEND FOR TEMPS AS THEY LOOK REASONABLE.
&&
.AVIATION /DISCUSSION FOR THE 091800Z TAFS/...
ISSUED AT 1234 PM EDT WED MAY 9 2012
VFR CONDITIONS EXPECTED TO PREVAIL THROUGH THIS TAF PERIOD...
A WEAK UPPER LEVEL TROUGH IS CURRENTLY MAKING IT/S WAY THROUGH
CENTRAL INDIANA AND SHOULD PUSH EAST OF THE REGION TONIGHT. FORECAST
SOUNDINGS INDICATE A DRY COLUMN...HOWEVER CONVECTIVE TEMPERATURES
HAVE BEEN REACHED IN MANY LOCATION ALREADY...PRODUCING SCT-BKN CU.
WITH CCL/S NEAR 4000 FT...ANY CIGS WILL BE VFR. A FEW WIDELY
SCATTERED SPRINKLES ARE POSSIBLY THIS AFTERNOON...PER THE RAPID
REFRESH BUT DO NOT FEEL CONFIDENT ENOUGH TO MENTION VCSH AT THIS
TIME...AND IN EITHER CASE THIS SHOULD NOT HAVE AN IMPACT OF THE
FLIGHT CATEGORY. AS HEATING IS LOST AFTER SUNSET...CU WILL
DISSIPATE LEADING TO CLEAR SKIES. SUBSIDENCE WILL CONTINUE
OVERNIGHT AND WITH DEW POINTS EXPECTED IN THE UPPER 30S...FOG IS
NOT ANTICIPATED.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...CP
SHORT TERM...CP
LONG TERM....MRD/CP
AVIATION...SMF
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1126 AM MDT WED MAY 9 2012
.UPDATE...
ISSUED AT 1019 AM MDT WED MAY 9 2012
BASED ON THE LATEST OBSERVATIONS HAVE INCREASED HIGH TEMPERATURES
TODAY A FEW DEGREES...WITH SOME LOCATIONS WARMING INTO THE LOW
80S. ALSO INCREASED THE WINDS OVER THE MAJORITY OF THE AREA
THROUGH THE EARLY AFTERNOON. LATEST RUC SURFACE ANALYSIS HAS A
TIGHTER PRESSURE GRADIENT OVER THE CENTRAL PART OF THE
AREA...WHICH CORRESPONDS WELL WITH THE LOCATION OF THE STRONGER
WINDS. GUIDANCE HAS THE WINDS DECREASING DURING THE MID
AFTERNOON...BUT SURFACE PRESSURE GRADIENT DOES NOT WEAKEN MUCH.
WILL MONITOR TO SEE IF WINDS WILL NEED TO BE INCREASED THROUGH THE
AFTERNOON.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY NIGHT)
ISSUED AT 215 AM MDT WED MAY 9 2012
A RIDGE WILL BE OVER THE PLAINS TODAY THROUGH THURSDAY. THE RIDGE
WILL MOVE EAST WITH WESTERLY FLOW OVER KANSAS FROM THURSDAY NIGHT
THROUGH FRIDAY NIGHT. A TROUGH WILL MOVE ACROSS THE NORTHERN PLAINS
BEHIND THE RIDGE AS IT MOVES INTO THE GREAT PLAINS. SURFACE HIGH
PRESSURE WILL SHIFT EAST INTO THE MISSOURI VALLEY TODAY. A SURFACE
TROUGH WILL MOVE INTO EASTERN COLORADO TONIGHT AND CONTINUE THERE
THURSDAY. THE TROUGH WILL MOVE EAST ACROSS KANSAS THURSDAY NIGHT
ALLOWING A COLD FRONT INTO NORTHWEST KANSAS ON FRIDAY. HIGH PRESSURE
WILL MOVE INTO WESTERN KANSAS FRIDAY NIGHT.
POPS WILL BE NIL THROUGH THURSDAY EVENING WITH SUBSIDENCE OVER THE
AREA. DYNAMICS APPROACH THE NORTHWEST CORNER OF THE FA LATE THURSDAY
NIGHT SO WILL KEEP THE CURRENT SLIGHT CHANCE POP FOR A SMALL PORTION
OF YUMA COUNTY. POPS WILL BE TIED TO THE FRONT AS IT MOVES ACROSS
THE FA FRIDAY. DYNAMICS ARE NOT THAT IMPRESSIVE WITH THE FRONT SO
WILL KEEP POPS IN THE SLIGHT CHANCE CATEGORY. MOISTURE AND DYNAMICS
IMPROVE OVERNIGHT FRIDAY NIGHT SO HAVE INCREASED THE AREA OF CHANCE
POPS FURTHER EAST.
PLAN TO KEEP CURRENT FROST ADVISORY GOING IN THE NORTHEAST WHERE
DEW POINTS ARE IN THE UPPER 20S. CLEAR SKIES AND LIGHT WIND WILL
MAKE IT POSSIBLE FOR TEMPERATURES TO FALL INTO THE FROST CATEGORY.
MAX TEMPERATURES WILL CONTINUE TO WARM THROUGH THURSDAY AHEAD OF THE
COLD FRONT. MAX TEMPERATURES FRIDAY WILL BE ABOUT 20 DEGREES COOLER
WITH READINGS IN THE 60S. MIN TEMPERATURES WILL FALL TO THE UPPER
40S/LOWER 50S TONIGHT/THURSDAY NIGHT. MIN TEMPERATURES FRIDAY NIGHT
SHOULD RANGE FROM THE LOWER 40S IN EASTERN COLORADO TO THE UPPER 40S
IN THE EASTERN FA.
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 215 AM MDT WED MAY 9 2012
THE NUMERICAL GUIDANCE IS IN DECENT AGREEMENT WITH THE 500MB HEIGHT
AND FLOW PATTERN THROUGH MOST OF THE EXTENDED PERIOD. THE AREA WILL
START WITH WESTERLY FLOW ON SATURDAY SWITCHING TO NORTHERLY FLOW BY
THE END OF THE PERIOD ON THE DOWNSTREAM SIDE OF BUILDING HEIGHTS
OVER THE WESTERN CONUS. AT THE SURFACE...HIGH PRESSURE WILL BE
LOCATED OVER THE NORTHERN PLAINS TO START THE PERIOD WHICH WILL PUT
THE AREA IN COOL UPSLOPE FLOW. CLOUDY SKIES AND DECENT CHANCES FOR
PRECIPITATION CAN BE EXPECTED THROUGH SUNDAY. WITH LIMITED
INSTABILITY WILL KEEP MAINLY SHOWERS GOING THROUGH SUNDAY AFTERNOON
AT WHICH TIME INSTABILITY MAY INCREASE ENOUGH TO PRODUCE ISOLATED
THUNDERSTORMS. HOWEVER...MOST OF THE PRECIPITATION SHOULD BE OUT OF
THE AREA. LARGE SCALE SUBSIDENCE MOVES INTO THE AREA FOR MONDAY AND
TUESDAY...EFFECTIVELY ENDING THE PRECIPITATION AND DECREASING
CLOUDS. TEMPERATURES FOR SATURDAY AND SUNDAY WILL BE BELOW AVERAGE
WITH A MODERATING TREND TO NEAR AVERAGE TEMPERATURES MONDAY AND
TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1109 AM MDT WED MAY 9 2012
VFR CONDITIONS ARE FORECAST FOR THE 18Z TAFS. LIGHT WINDS...WITH
AN OCCASIONAL GUST...WILL OCCUR THROUGH THE AFTERNOON. DURING THE
NIGHT THE WINDS WILL TURN TO THE SOUTHWEST IN RESPONSE TO THE
SURFACE TROUGH OVER EASTERN COLORADO. THE WINDS TURN BACK TO THE
SOUTH DURING THE LATE MORNING THURSDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...FS
LONG TERM...BAS
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1024 AM MDT WED MAY 9 2012
.UPDATE...
ISSUED AT 1019 AM MDT WED MAY 9 2012
BASED ON THE LATEST OBSERVATIONS HAVE INCREASED HIGH TEMPERATURES
TODAY A FEW DEGREES...WITH SOME LOCATIONS WARMING INTO THE LOW
80S. ALSO INCREASED THE WINDS OVER THE MAJORITY OF THE AREA
THROUGH THE EARLY AFTERNOON. LATEST RUC SURFACE ANALYSIS HAS A
TIGHTER PRESSURE GRADIENT OVER THE CENTRAL PART OF THE
AREA...WHICH CORRESPONDS WELL WITH THE LOCATION OF THE STRONGER
WINDS. GUIDANCE HAS THE WINDS DECREASING DURING THE MID
AFTERNOON...BUT SURFACE PRESSURE GRADIENT DOES NOT WEAKEN MUCH.
WILL MONITOR TO SEE IF WINDS WILL NEED TO BE INCREASED THROUGH THE
AFTERNOON.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY NIGHT)
ISSUED AT 215 AM MDT WED MAY 9 2012
A RIDGE WILL BE OVER THE PLAINS TODAY THROUGH THURSDAY. THE RIDGE
WILL MOVE EAST WITH WESTERLY FLOW OVER KANSAS FROM THURSDAY NIGHT
THROUGH FRIDAY NIGHT. A TROUGH WILL MOVE ACROSS THE NORTHERN PLAINS
BEHIND THE RIDGE AS IT MOVES INTO THE GREAT PLAINS. SURFACE HIGH
PRESSURE WILL SHIFT EAST INTO THE MISSOURI VALLEY TODAY. A SURFACE
TROUGH WILL MOVE INTO EASTERN COLORADO TONIGHT AND CONTINUE THERE
THURSDAY. THE TROUGH WILL MOVE EAST ACROSS KANSAS THURSDAY NIGHT
ALLOWING A COLD FRONT INTO NORTHWEST KANSAS ON FRIDAY. HIGH PRESSURE
WILL MOVE INTO WESTERN KANSAS FRIDAY NIGHT.
POPS WILL BE NIL THROUGH THURSDAY EVENING WITH SUBSIDENCE OVER THE
AREA. DYNAMICS APPROACH THE NORTHWEST CORNER OF THE FA LATE THURSDAY
NIGHT SO WILL KEEP THE CURRENT SLIGHT CHANCE POP FOR A SMALL PORTION
OF YUMA COUNTY. POPS WILL BE TIED TO THE FRONT AS IT MOVES ACROSS
THE FA FRIDAY. DYNAMICS ARE NOT THAT IMPRESSIVE WITH THE FRONT SO
WILL KEEP POPS IN THE SLIGHT CHANCE CATEGORY. MOISTURE AND DYNAMICS
IMPROVE OVERNIGHT FRIDAY NIGHT SO HAVE INCREASED THE AREA OF CHANCE
POPS FURTHER EAST.
PLAN TO KEEP CURRENT FROST ADVISORY GOING IN THE NORTHEAST WHERE
DEW POINTS ARE IN THE UPPER 20S. CLEAR SKIES AND LIGHT WIND WILL
MAKE IT POSSIBLE FOR TEMPERATURES TO FALL INTO THE FROST CATEGORY.
MAX TEMPERATURES WILL CONTINUE TO WARM THROUGH THURSDAY AHEAD OF THE
COLD FRONT. MAX TEMPERATURES FRIDAY WILL BE ABOUT 20 DEGREES COOLER
WITH READINGS IN THE 60S. MIN TEMPERATURES WILL FALL TO THE UPPER
40S/LOWER 50S TONIGHT/THURSDAY NIGHT. MIN TEMPERATURES FRIDAY NIGHT
SHOULD RANGE FROM THE LOWER 40S IN EASTERN COLORADO TO THE UPPER 40S
IN THE EASTERN FA.
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 215 AM MDT WED MAY 9 2012
THE NUMERICAL GUIDANCE IS IN DECENT AGREEMENT WITH THE 500MB HEIGHT
AND FLOW PATTERN THROUGH MOST OF THE EXTENDED PERIOD. THE AREA WILL
START WITH WESTERLY FLOW ON SATURDAY SWITCHING TO NORTHERLY FLOW BY
THE END OF THE PERIOD ON THE DOWNSTREAM SIDE OF BUILDING HEIGHTS
OVER THE WESTERN CONUS. AT THE SURFACE...HIGH PRESSURE WILL BE
LOCATED OVER THE NORTHERN PLAINS TO START THE PERIOD WHICH WILL PUT
THE AREA IN COOL UPSLOPE FLOW. CLOUDY SKIES AND DECENT CHANCES FOR
PRECIPITATION CAN BE EXPECTED THROUGH SUNDAY. WITH LIMITED
INSTABILITY WILL KEEP MAINLY SHOWERS GOING THROUGH SUNDAY AFTERNOON
AT WHICH TIME INSTABILITY MAY INCREASE ENOUGH TO PRODUCE ISOLATED
THUNDERSTORMS. HOWEVER...MOST OF THE PRECIPITATION SHOULD BE OUT OF
THE AREA. LARGE SCALE SUBSIDENCE MOVES INTO THE AREA FOR MONDAY AND
TUESDAY...EFFECTIVELY ENDING THE PRECIPITATION AND DECREASING
CLOUDS. TEMPERATURES FOR SATURDAY AND SUNDAY WILL BE BELOW AVERAGE
WITH A MODERATING TREND TO NEAR AVERAGE TEMPERATURES MONDAY AND
TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 517 AM MDT WED MAY 9 2012
VFR CONDITIONS WILL CONTINUE FOR THE NEXT 24 HOURS AT KGLD AND
KMCK AS HIGH PRESSURE RESIDES OVER THE CENTRAL PLAINS. WINDS WILL
BE LIGHT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...FS
LONG TERM...BAS
AVIATION...FS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
652 PM EDT WED MAY 09 2012
.Forecast Update...
Issued at 650 PM EDT WED May 9 2012
Scattered showers in central Indiana have been holding their own as
they push quickly to the southeast, and there has even been some new
development between Indy and Bloomington along with an increase in
lightning production. The showers are only a couple counties away
from the LMK CWFA at this point, so a decision needed to be made
regarding PoPs this evening (which were dry). After looking at KIND
radar and HRRR progs, have decided to go ahead and insert SCT/ISO
PoPs into the north, basically north of a line from Paoli to
Louisville to Lexington. The showers should fizzle as they reach
the Blue Grass around mid-evening, and we have the PoPs stopping at
02Z.
.Short Term (Tonight through Thursday night)...
Issued at 245 PM EDT May 9 2012
A weak upper disturbance is rotating southeast across the lower
Great Lakes region, sparking off not only widespread, high-based
strato-cu, but also showers and even a few storms across IL/IN/OH.
Most of this activity will stay to our north, however our
northeastern CWA could see some sprinkles perhaps by early evening.
By that time, clouds/precip will start to dissipate with the loss of
afternoon heating, so will keep just the sprinkle wording in the
grids. Best time frame/location will be between 5-10pm northeast of
a line from Louisville to Lexington. Until that timeframe, expect
gusty northwest winds and partly cloudy skies.
Once that trough swings through by roughly midnight, we`ll have
clearing skies thereafter as surface high pressure starts to slide
in from the west. Winds will become light and will help overnight
lows drop into the low-mid 40s north to around 50 south.
The center of the surface high will still be to our west Thursday,
so a steady northerly wind will be in place. Even a few gusts to
about 15 knots or so will be possible especially east of I-65
tomorrow with good mixing. Although skies will be sunny, a steady
northerly wind will keep temps around the same highs as today, maybe
even a tad cooler. Look for highs in the mid-upper 60s north and
east, to the low 70s over the southwest.
Thursday night should be the coolest night with the surface high
directly overhead. Winds will be calm, and with excellent
radiational cooling, lows will plummet into the low 40s most places.
Wouldn`t be surprised to see a few sheltered, Bluegrass locations
drop into the upper 30s.
.Long Term (Friday through Wednesday)...
Issued at 318 PM EDT May 9 2012
Friday Through Sunday Night...
The Ohio Valley will start off in northwesterly flow on Friday as a
large trough exits in the northeast US and weak mid-level low moves
into the southern Plains. High pressure will remain in control of
the weather with dry conditions Friday/Friday night. Short term
shot of upper ridging ahead of the approaching southern Plains wave
will keep the region dry on Saturday, but we`ll likely see a quick
increase in cloud cover throughout the day. Combination of
southerly return flow and isentropic ascent will likely lead to some
isolated showers/storms develop Saturday night especially across
southern KY. Better moisture and synoptic scale lift look much
better on Sunday which looks to be rather dreary with extensive
cloud cover and scattered to numerous showers/storms dotting the
region as the upper wave moves across the region. Clouds and
convection are likely to continue Sunday night as the upper wave
slowly moves east and a surface low and cold front push through the
region. Basically have done an incremental update here as the
previous forecast has this well handled. Given the increasing
forecast convergence here, have raised PoPs a little during the
Sun/Sun night period.
Highs Friday and Saturday will generally be in the mid-upper 70s but
cool into the lower 70s for Sunday. Overnight temps look to remain
rather mild with readings in the upper 40s to the lower 50s.
Monday through Wednesday...
This afternoons long term deterministic and ensemble guidance is in
general agreement with the upper level flow across the CONUS in this
time frame. By and large, the models suggest that a large ridge
will build across the western US early in the period which will
force a downstream trough to develop across the eastern US. A
decent mid-level wave looks to crash into the western US coast by
late in the period which will likely knock down that western ridge.
Considerable spread exists in the height fields across the east
during the period with regards to whether we`ll see a closed low
develop. The 09/00Z and 09/12Z GFS offer the one extreme with a
very pronounced cut off low developing over the east and then
meandering slowly to the east as the flow becomes a bit more zonal.
The 09/00Z and 09/12Z GFS ensembles are not as robust with the upper
low development and actually have a little less spread when compared
with the 09/00Z and 09/12Z OP Euro and its ensembles. Suffice to
say, forecast confidence is average at the beginning of the period
with confidence dropping in the day 6/7 (Tue/Wed) timeframe as the
uncertainty with possible closed low develop complicate the
forecast. With this issuance, have leaned closer the 12Z GFS
Ensemble and Euro solutions which gives decent continuity to the
previous forecast.
This period of the forecast will likely be a rather unsettled one
with the upper trough being situated over the eastern US. Variable
cloudiness is likely with chances of rain throughout the period. It
does seem likely that the best chances of precipitation would be in
the Monday/Tuesday time frame as the trough moves over us with
lesser chances on Wednesday as the GEFS/Euro solutions are slightly
more progressive. For now, will keep slight to low chance PoPs
going with a drier trend for Wednesday. Depending on how the upper
level pattern evolves, future forecasts will likely need some
adjustments over the next few days. As for temperatures, readings
should generally be a little below average with daytime highs in the
upper 60s to lower 70s and overnight lows in the lower-middle 50s.
&&
.Aviation (00Z TAF Issuance)...
Updated at 650 PM EDT May 9 2012
Gusty winds at the terminals are expected through the next couple of
hours until the atmosphere decouples. The CU field has also already
begun to dissipate with clear skies expected overnight. Winds will
be fairly light out of the NNE through the overnight hours. Surface
high pressure will slide into the area tomorrow. Cloud cover will be
fairly limited, though some CU may develop. Winds will be out of the
north and lighter than today, in generally the 7-12 knot range, with
a few higher gusts. Winds will begin to shift to the east after 0Z
tomorrow at SDF as the high pressure shifts eastward.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........13
Short Term.......AL
Long Term........MJ
Aviation.........EER
AREA FORECAST DISCUSSION
NWS CARIBOU ME
330 PM EDT WED MAY 9 2012
.SYNOPSIS...
LOW PRESSURE DEVELOPING OFF THE MID ATLANTIC STATES TONIGHT WILL
MOVE UP THE EAST COAST THURSDAY AND MOVE THROUGH SOUTHEAST MAINE
EARLY THURSDAY EVENING.
&&
.NEAR TERM /THROUGH THURSDAY/...
HAVE USED POP FROM RADAR TOOL TO INITIALIZE POP GRIDS DURING THE
AFTERNOON THEN BLEND THIS WITH HRRR POPS LATER IN DAY. FOR TONIGHT
AND TOMORROW HAVE USED A BLEND OF THE NAM12...GFS40 AND SREF FOR
POPS. HAVE MADE SOME MANUAL ADJUSTMENTS TO BRING POPS TO 100
PERCENT DURING HIGHEST PROBABILITY PERIODS. CURRENTLY ONE AREA OF
RAIN MOVING NORTHEAST THROUGH GULF OF MAINE BUT EXPECT MOST OF
THIS TO STAY OFF-SHORE. FOR QPF HAVE USED A BLEND OF THE
CANADIAN...GFS40...NAM80...ECMWF AND SREF. THE OPERATIONAL NAM
GIVES HIGHER AMOUNTS BUT THINK THIS IS TOO HIGH. SREF NUMBERS ARE
MUCH LOWER THAN OPERATIONAL NAM AND SREF 24-HR PROBABILITY GREATER
THAN TWO INCHES IS UNDER 40 PERCENT...EVEN IN VICINITY OF EASTPORT
WHICH IS CLOSES TO HIGHEST MOST MODEL QPF MAXIMUMS. ALSO MOST
GUIDANCE INDICATES JET MAXIMUM FURTHER TO SOUTHEAST. THIS ALL
SUPPORTS THINKING THAT CURRENT OPERATIONAL NAM QPF IS TOO HIGH.
FOR WINDS HAVE USED A BLEND OF THE NAM12 AND GMOS. TEMPERATURE AND
DEW POINT GENERATED WITH THE GMOS.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
LOW PRESSURE WILL LIFT NORTHEAST THROUGH THE MARITIMES THURSDAY
NIGHT THROUGH FRIDAY. THIS WILL RESULT IN THE STEADIER RAIN ENDING
EARLY THURSDAY EVENING. HOWEVER...AN UPPER LEVEL TROUGH WILL
SLOWLY CROSS THE REGION THROUGH FRIDAY WITH MOSTLY CLOUDY SKIES AND
THE CHANCE FOR SHOWERS THROUGH FRIDAY. THE UPPER LEVEL TROUGH WILL
SLOWLY MOVE EAST FRIDAY NIGHT THROUGH SATURDAY WITH IMPROVING
CONDITIONS. THIS WILL SET THE STAGE FOR A RATHER NICE DAY SATURDAY
AS BRIEF UPPER LEVEL RIDGING BUILDS IN AHEAD OF THE NEXT SHORT
WAVE. TEMPERATURES ON FRIDAY WILL BE A BIT BELOW NORMAL FOR THIS
TIME OF YEAR AND THEN BE NEAR NORMAL ON SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE EXTENDED MODELS ARE IN GOOD GENERAL AGREEMENT EARLY IN THE
PERIOD. A LOW OVER NR QUEBEC...AND A HIGH PRESSURE RIDGE ALONG
THE ERNA SEABOARD ARE THE MAIN WEATHER FEATURES AT THE START OF THE
PERIOD. THESES SYSTEM WILL REMAIN IN PLACE AS A NEW LOW DEVELOPS
ALONG THE MISSISSIPPI GULF COAST SUNDAY NIGHT. BY MONDAY MORNING
THE GS AND EMF ARE SHOWING A DIFFERENT SOLUTION THE RESULTING
CONDITIONS WILL BE SIMILAR. THE GS DEEPENS THE LOW AND KEEPS IT
OVER THE GULF OF MEXICO WITH A TR OF EXTENDING NE INTO THE
APPALACHIANS. THE EMF MOVE THE LOW NORTH INTO NR MS. WITH A WEAK
WARM FRONT EXTENDING EAST INTO THE APPALACHIANS. BY MONDAY EVENING
THE GS MOVES THE LOW INTO SEN MS... THE LOW OVER QUEBEC SWINGS SE
INTO SEN QUEBEC. A COLD FRONTAL SYSTEM DEVELOPS ALONG THE ERNA
SEABOARD EXTENDING BTW THESE TWO LOWS. AT THIS POINT THE EMF
AGREES WITH THE GS ON THE QUEBEC LOW AND COLD FRONT. THE SEN LOW
ORV ERNA AL. ORV THE NEXT 24HRS THE FRONT WILL BE STATIONARY ALONG
THE ERNA SEABOARD WITH THE SEN LOW MOVING NORTH ALONG THE FRONTAL
BINDERY. THE GS MOVES IT NE INTO THE ATLANTIC ALONG THE VA/NC
BORDER. THE EMF NE TO SEN PA/NR VA. THE NR LOW EAST INTO THE
WREN CANADIAN MARI TIMES. BY WEDNESDAY MORNING THE SYSTEM WILL MOVE
EAST INTO THE NORTH ATLANTIC (GS)...INTO THE SEN GULF OF MAINE
WATERS (EMF). BY WEDNESDAY EVENING THE BOTH SYSTEMS MOVE THE
FRONT EAST OF THE AREA...A WRAP AROUND LOW WILL BACK INTO THE ST
LAWRENCE WEDNESDAY NIGHT. BY THURSDAY MORNING A NEW LOW MOVE SE
OUT OF NR CANADA AND INTO NR ME BY EARLY AFTERNOON. THIS SYSTEM
WILL REMAIN IN THE AREA THROUGH THE END OF THE PERIOD.
LOADED GM OS...MADE MINOR ADJUSTMENTS TO SKY AND POPS THROUGH THE
MID PORTION OF THE FORECAST. POPS TO HIGH FOR THE SKY CON FORECAST.
LOADED NA WAVE 4 FOR SEAS IN THE COASTAL WATERS. ADDED 20 PERCENT
FOR ENDS ORV THE WATERS...15 PERCENT ORV LAND.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
NEAR TERM: EXPECT IFR CONDITIONS NEXT 24 HOURS.
SHORT TERM: MAINLY FR THROUGH THE PERIOD BUT PERIODS OF MVFR ARE
POSSIBLE THURSDAY NIGHT THROUGH FRIDAY IN ANY SHOWERS.
&&
.MARINE...
NEAR TERM: HAVE USED NAM12 WINDS WHICH APPEARS TO BE DOING THE
BEST JOB OF HANDLING THE BOUNDARY LAYER. WAVES: VERY LONG FETCH IS
CURRENTLY IN PLACE FROM THE GULF OF MAINE SOUTHEASTWARD WELL INTO
ATLANTIC. EXPECT LONG PERIOD WAVE FROM THIS FETCH TO EFFECT WATERS
THROUGH THE WEEKEND. WNA/WAVE CONTINUES TO INCREASE WIND SPEED
ACROSS THIS FETCH TONIGHT INTO THURSDAY. THINK WNA WINDS A LITTLE
TOO HIGH IN GULF OF MAINE DUE TO COLD SEA SURFACE TEMPERATURE
UNDER WARM ADVECTION RESULTING IN INVERSION....HOWEVER WINDS
FORECAST ACROSS MOST OF FETCH LOOKS REASONABLE. HAVE USED SWAN/NAM
TO INITIALIZE WAVES FOR THIS PERIOD. WILL INCREASE SWAN WAVE
HEIGHTS 1 TO 2 FEET LATER THURSDAY MORNING INTO THURSDAY
AFTERNOON. REMAINDER OF SWAN LOOKS GOOD. WILL USE LAMP25 FOR
VISIBILITY. HAVE EXTEND SCA THROUGH TOMORROW NIGHT.
SHORT TERM: SEAS WILL LIKELY REMAIN AT OR NEAR SMALL CRAFT ADVISORY
LEVELS THURSDAY NIGHT AND INTO FRIDAY. CONDITIONS WILL THEN DROP
BELOW SMALL CRAFT ADVISORY LEVELS LATER FRIDAY AND SATURDAY. FOR
WAVES USED SWAN NAM THROUGH THE PERIOD.
&&
.HYDROLOGY...
LOW PRESSURE CURRENTLY DEVELOPING OFF THE MID ATLANTIC STATES ALONG
THE EAST COAST LATE TONIGHT AND THEN TRACK NORTHWARD MOVING ACROSS
WASHINGTON COUNTY BY THURSDAY EVENING. TWO TO THREE INCHES OF RAIN
IS POSSIBLE FOR HANCOCK AND WASHINGTON COUNTIES FROM LATE TONIGHT
THROUGH THURSDAY NIGHT WITH THIS LOW PRESSURE. EXCESSIVE RUNOFF
FROM HEAVY RAINFALL MAY CAUSE ELEVATED LEVELS ON SMALL BROOKS AND
STREAMS AND POSSIBLE MINOR FLOODING IN POOR DRAINAGE AREAS AND LOW
LYING SPOTS.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EDT FRIDAY FOR ANZ050>052.
&&
$$
NEAR TERM...MIGNONE
SHORT TERM...DUDA
LONG TERM...NORTON
AVIATION...MIGNONE
MARINE...MIGNONE/DUDA
HYDROLOGY...HASTINGS
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
147 PM EDT WED MAY 9 2012
.SYNOPSIS...
A COLD FRONT SLOWLY CROSSES THE REGION TODAY...THEN MOVES OFF THE
COAST TONIGHT. HIGH PRESSURE BUILDS INTO THE AREA THURSDAY THROUGH
THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
INITIAL FRONT ALMOST STALLED NORTHEAST TO SOUTHWEST ACROSS CENTRAL
VIRGINIA. THE MODELS ARE DEPICTING THIS MOVING ONLY SLOWLY EAST
WHILE A STRONGER FRONT IN THE OHIO VALLEY CATCHES UP WITH IT THIS
EVENING. HAVE ONE AREA OF PRECIPITATION ALONG THE INITIAL FRONT.
THESE SHOWERS WILL SLOWLY DIMINISH INTO EARLY AFTERNOON. FARTHER
WEST CAN SEE MORE SHOWERS DEVELOPING AND ENHANCING IR IMAGE. THIS
CORRESPONDS TO INCREASING DIVERGENCE FROM THE JET. MODELS MOVE
THIS AREA INTO MUCH OF THE COUNTY WARNING AREA DURING THE
AFTERNOON AND EVENING. ALSO WITH STRONG POTENTIAL VORTICITY MAX
MOVING OVER THE AREA THIS EVENING WILL ENHANCE THE LIFT AS WELL.
SO PLENTY OF RAIN AND SOME OF IT WILL BE QUITE HEAVY AS
PRECIPITABLE WATER OVER 180 PERCENT OF NORMAL.
PLENTY OF QUESTION ON THUNDERSTORMS AND IF ANY WILL BE SEVERE. DO
HAVE A FEW BREAKS IN CENTRAL VIRGINIA BUT THIS WILL FILL IN
QUICKLY THIS AFTERNOON AND THIS LIMITS THE HEATING. ALSO LAPSE
RATES ARE FAIRLY WEAK LIMITING INSTABILITY. ALSO WHILE THE SHEAR
DOES INCREASE TOWARD EVENING BY THEN THE INSTABILITY IS WEAKENING.
DO BELIEVE THERE WILL BE SOME THUNDER THIS EVENING WITH THE STRONG
LIFT AND CAN NOT RULE OUT AN ISOLATED WET MICRO BURST BUT EXPECT
ANY SEVERE TO BE VERY LIMITED.
BECAUSE OF SOME BREAKS IN CLOUDS IN THE WEST RAISED MAXES THERE A
LITTLE WHILE LOWERED THEM FARTHER TO THE EAST. THIS CORRESPONDS
WELL WITH HRRR AND RUC AS WELL AS GRIDDED LAMP DATA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
EXPECT A "JUMP" IN THE FRONTAL BOUNDARY TO COASTAL SECTIONS EARLY
THIS EVENING BEHIND FIRST EXITING S/W. SECOND (POST FRONTAL) IMPULSE
THEN PROGGED TO QUICKLY MOVE NE ALONG THE BOUNDARY THIS EVENING
KEEPING CATEGORICAL POPS GOING MOST AREAS. HEAVIEST RAINFALL EXPECTED
EAST OF I95 AND HAVE ADDED LOCALLY HEAVY RAINFALL TO THE COUNTIES
AROUND AND EAST OF THE CHES BAY THIS EVENING. ANY SEVERE THREAT ENDS
QUICKLY THIS EVENING.
FRONT MOVES OFFSHORE AROUND OR SHORTLY AFTER MIDNIGHT. PCPN CHANCES
QUICKLY TAPER OFF (AND END ACROSS WESTERN HALF OF FA) AS SECOND S/W
PULLS AWAY FROM THE REGION. TEMPS FALL INTO THE 50S AS CAA REMAINS
RATHER WEAK. EXPECT A WIDE QPF WITH THIS SYSTEM. AROUND .50 INCH
ACROSS EXTREME WESTERN COUNTIES UPWARDS TO 1.50 INCHES ACROSS SERN
AREAS WHERE THE HEAVIEST RAINFALL IS EXPECTED.
SOME LINGERING SHWRS ALONG THE IMMEDIATE COASTAL AREAS PUSH OFFSHORE
ARND 12Z THURSDAY. LARGE RIDGE OF HIGH PRESSURE PROGGED TO BUILD INTO
REGION THURSDAY AFTERNOON AND FRIDAY. LINGERING WRAP ARND MSTR MAY
ENHANCE AFTERNOON SC ACROSS LWR MD ERN SHORE THURSDAY. OTW...TSCTNS
SHOW A QUICK COLUMN DRYING SO IT SHOULD END UP M SUNNY. DESPITE THE
INCREASING SUNSHINE...CAA KEEPS TEMPS IN THE L-M70S. CLEAR AND COOL
THURSDAY NIGHT. LOWS M40S-M50S. RIDGE AXIS STILL WEST OF FA FRIDAY.
M SUNNY WITH HIGHS IN THE L-M70S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
HIGH PRESSURE GRADUALLY MOVES OFFSHORE THIS WEEKEND WITH THE NEXT
FRONT APPROACHING BY MONDAY. RETURN FLOW RESULTS IN A GRADUAL WARMUP.
LATEST DATA SUGGESTS HIGHS THIS WEEKEND BETWEEN 75-80 SO HAVE BUMBED
UP TEMPS A BIT. PATTERN SLOWLY TRANSITIONS TO A WET PATTERN TOWARD
THE MIDDLE OF NEXT WEEK. MODELS HAVE SOME CHANGES THAT COULD AFFECT
OUR WEATHER NEXT WEEK. KEPT POPS AT 20 PERCENT SUNDAY NIGHT THROUGH
MONDAY NIGHT AS CONFIDENCE IN PCPN IS NOT HIGH ENOUGH TO MENTION IN
THE FCST. LOW PRESSURE SLOWLY PULLS NORTHEAST FROM THE WESTERN GULF
COAST REGION AND BRINGS A GOOD CHANCE FOR PCPN BY TUESDAY. WENT NO
HIGHER THAN 30 PERCENT THIS FAR OUT AS THE TIMING COULD CHANGE.
HIGHS IN THE 70S NEXT WEEK WITH LOWS IN THE 50S.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
SCATTERED SHOWERS WILL CONTINUE OVER THE AREA THROUGH THIS EVENING
AS A COLD FRONT SLOWLY APPROACHES FROM THE WEST. CONVECTION POSSIBLE
MAINLY IN SE PORTIONS AND INCLUDED TEMPO TSTM AT ORF 19-21Z WITH
TSTMS TO THE SW NEAR THE VA/NC BORDER. UPDATE FOR RIC MAY BE NEEDED
AS ISOLATED CONVECTION MAY DEVELOP IN CENTRAL VA NEXT FEW HOURS.
WILL MONITOR FOR PSBL TSTM POTENTIAL AT ECG TOWARDS EVENING.
PCPN EXPECTED FOR 3-5 HOURS AFTER FRONTAL PASSAGE. IFR CEILINGS ARE
A GOOD POSSIBILITY AT ORF/ECG DURING THIS TIME PER NAM MOS AND
CLIMATOLOGY WITH ANAFRONTAL SITUATIONS. WINDS TURN TO NW/N AROUND
02-06Z FROM NW TO SE WITH AN INITIAL EXTRA VEERING IMMEDIATELY
BEHIND THE FRONT (ESPECIALLY AT ORF). WINDS TO BE GUSTY FROM THE NW
DURING THE DAY THURSDAY AND FOLLOWED CLOSE TO LAVMOS. NAM BUFR
SOUNDINGS INDICATE STRATOCU POTENTIAL AFTER AROUND 14-15Z.
OUTLOOK...MAINLY VFR CONDITIONS THROUGH THE WEEKEND. NO IFR EXPECTED
FRI MRNG DUE TO LOW DEW POINTS AND A NW BREEZE DESPITE WET GROUND.
CHC PCPN EARLY NEXT WEEK.
&&
.MARINE...
HIGH PRES PERSISTS OFF TO THE EAST AS A COLD FRNT APPROACHES FROM
THE WEST TDY. SCA HAS BEEN DROPPED FOR THE MOUTH OF THE BAY WHERE
WAVES HAVE STAYED BELO 4 FT. ELSEWHERE...SOUTHERLY WINDS ARE JUST
BELO SCA THRESHOLDS OVR THE BAY...AND SPEEDS SHUD DIMINISH BY MIDDAY
AS THE 925 MB JET STREAK WEAKENS. THE SCA OVR COASTAL WATERS
CONTINUES THRU TNGT WITH 4-5 FT SEAS EXPECTED IN ASSOCIATION WITH
A PROLONGED S/SE FETCH AND 15-20 KT WINDS. WINDS OVR THE BAY MAY
REACH SCA THRESHOLDS FOR A SHORT DURATION TNGT WITH THE
FROPA...BUT WILL HOLD OFF ON ANY HEADLINES FOR THIS ATTM DUE TO
THE SHORT DURATION AND TIMING UNCERTAINTIES.
BEYOND TNGT...THE NEXT CHANCE FOR MARGINAL SCA CONDS WILL OCCUR
BEHIND THE COLD FRNT THU WITH W/NW WINDS. ANOTHER WEAK SURGE MAY
ARRIVE FRI MRNG. QUIET CONDS OVR THE WATERS INTO THE WEEKEND WITH
HIGH PRES IN PLACE.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EDT THURSDAY FOR ANZ654-656-
658.
SMALL CRAFT ADVISORY UNTIL 4 AM EDT THURSDAY FOR ANZ650-652.
&&
$$
SYNOPSIS...MPR
NEAR TERM...MPR/JAB
SHORT TERM...MPR
LONG TERM...MPR/LSA
AVIATION...LSA
MARINE...MAS
AREA FORECAST DISCUSSION...UPDATED
NWS MARQUETTE MI
216 PM EDT WED MAY 9 2012
.UPDATE...
ISSUED AT 215 PM EDT WED MAY 9 2012
CLOUD FCST FM EARLIER TODAY DID NOT WORK OUT TOO WELL. SC/CU FORMED
BUT IT WAS MORE OVR CNTRL CWA WHILE THE EAST COMPLETELY CLEARED OUT
WITH STABILIZING FLOW OFF LK SUPERIOR. UPDATED GRIDS TO KEEP SCT CU
IN OVR CNTRL CWA UNTIL LATE AFTN BUT CLOUDS WILL CLEAR OUT BY
EVENING. GIVEN MOSTLY CLEAR SKIES TONIGHT STILL EXPECTING LOW TEMPS
TO FALL INTO UPR 20S TO MID 30S.
&&
.SYNOPSIS...
ISSUED AT 441 AM EDT WED MAY 9 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF OVER THE GULF OF
ALASKA...A DOWNSTREAM RIDGE EXTENDING FROM THE ROCKIES TO NUNAVUT
AND A TROF EXTENDING FROM QUEBEC THRU THE WRN GREAT LAKES. WITH A
SLOWLY PROGRESSIVE PATTERN...A QUIET 2-3 DAYS ARE ON THE WAY AS THE
UPSTREAM RIDGE SHIFTS E IN RESPONSE TO TROF MOVING INLAND FROM THE
GULF OF ALASKA. TROF WILL REACH THE UPPER LAKES LATE FRI...BRINGING
THE NEXT CHC OF -SHRA. AFTER A COOL DAY TODAY...A WARMING TREND WILL
GET UNDER WAY THU AND FRI AS WAA PATTERN DEVELOPS AHEAD OF THE TROF.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 441 AM EDT WED MAY 9 2012
WITH TROF AXIS SHIFTING SE OF UPPER MI...BACK EDGE OF
MOISTURE/CLOUDS IS PROGRESSING STEADILY SE ACROSS LAKE SUPERIOR
ATTM. PLENTY OF DRY AIR IN AN ABSOLUTE AND RELATIVE SENSE IS NOTED
UPSTREAM PER 00Z CWPL SOUNDING WHICH SHOWED PRECIPITABLE WATER OF
0.24 INCHES (AROUND 50PCT OF NORMAL) AND DWPT DEPRESSIONS GENERALLY
IN THE 10-25C RANGE FROM THE SFC TO ABOUT 500MB. WITH THE INFLUX OF
DRY AIR...THE FEW -SHRA/SPRINKLES NOTED ON KMQT RADAR WILL END IN
THE NEXT FEW HRS...AND CLOUDS WILL CLEAR OUT FROM NW TO SE TODAY. NOT
MUCH DIURNAL CU WAS NOTED UPSTREAM IN NRN ONTARIO YESTERDAY AFTN.
SHOULD BE A SIMILAR SITUATION HERE TODAY. THIS IDEA IS SUPPORTED BY
THE CU RULE WHICH SUGGESTS SCT DEVELOPMENT EARLIER IN THE DAY BEFORE
MIXING OF DRIER AIR BEGINS TO EAT AWAY AT THE CU. STABILIZING
INFLUENCE OF COOL FLOW OFF LAKE SUPERIOR WILL KEEP DAYTIME CU
INLAND...WITH CU PROGRESSIVELY FARTHER INLAND WITH TIME AS MARINE
LAYER INFLUENCE EXPANDS S. IT WILL BE A COOL DAY WITH 850MB
THERMAL TROF AROUND 0C SLOWLY SLIPPING E DURING THE AFTN. LOCATIONS
ALONG THE LAKE SUPERIOR SHORELINE SHOULD HOLD TO THE LOW/MID
40S...COOLEST OVER THE E. MIXING TO AROUND 800MB YIELDS MAX TEMPS IN
THE UPPER 50S/AROUND 60 TOWARD THE WI BORDER...WHICH IS INLINE WITH
UPSTREAM TEMPS IN NRN ONTARIO YESTERDAY.
AFTER A COOL DAY TODAY...STAGE WILL BE SET FOR A CHILLY/FROSTY
NIGHT TONIGHT AS SFC HIGH PRES RIDGE DRIFTS OVER THE AREA...
RESULTING IN WINDS DIMINISHING TO CALM/NEAR CALM UNDER MOSTLY CLEAR
SKIES. WITH PRECIPITABLE WATER RUNNING 50-75PCT OF NORMAL...
CONTINUED TO LEAN TOWARD THE LOW END OF AVBL GUIDANCE GIVEN THE
FAVORABLE RADIATIONAL COOLING CONDITIONS. TRADITIONAL COLD SPOTS IN
THE INTERIOR...ESPECIALLY W HALF...MAY SLIP INTO THE UPPER 20S. THAT
SAID...ONE POTENTIAL ISSUE THAT MAY LIMIT COOLING IS SOME CLOUD
COVER. MODELS SUGGEST THAT MID CLOUDS CURRENTLY OVER NRN MANITOBA AT
THE NOSE OF SOME WAA COULD DROP SE OVER THE AREA TONIGHT. SINCE THAT
WAA WEAKENS TO THE SE...EXPECT THE MID CLOUDS TO SHOW AT LEAST SOME
DECREASE IN COVERAGE AS THEY HEAD TOWARD THE AREA. OBVIOUSLY...CLOUD
TRENDS UPSTREAM TODAY WILL BE SOMETHING TO MONITOR DUE TO THE
POSSIBLE AFFECT ON MIN TEMPS TONIGHT.
UNDER SUNNY SKIES...A WARMER DAY IS EXPECTED THU WITH HIGH PRES IN
CONTROL AND 850MB TEMPS RISING TO 6 TO 10C BY LATE IN THE DAY. TEMPS
SHOULD REBOUND TO NEAR OR SLIGHTLY ABOVE NORMAL THOUGH LAKE BREEZES
SHOULD RULE LATE MORNING THRU THE AFTN TO PROVIDE COOLING NEAR THE
LAKES. MIXING UPWARDS OF 750MB YIELDS MAX TEMPS AROUND 70F OVER THE
INTERIOR W. TEMPS LAKESIDE WILL BE IN THE 40S/50S...DEPENDING ON HOW
EARLY LAKE BREEZE DEVELOPS AT EACH LOCATION.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 441 AM EDT WED MAY 9 2012
NAM SHOWS A 500 MB RIDGE OVER THE UPPER MISSISSIPPI RIVER VALLEY 00Z
FRI WITH TROUGHING AND A CLOSED LOW OVER NEW ENGLAND AND THE EASTERN
U.S...A CLOSED 500 MB LOW AND TROUGH NEAR IN NE MEXICO...AND A
TROUGH IN THE NORTHERN ROCKIES. THE 500 MB RIDGE MOVES INTO THE
UPPER GREAT LAKES ON FRIDAY. THE SHORTWAVE OVER THE NORTHERN ROCKIES
MOVES INTO THE UPPER GREAT LAKES FRIDAY NIGHT.
NAM BRINGS IN SOME 850-500 MB Q-VECTOR CONVERGENCE WITH DEEPER
MOISTURE MOVING IN FRI AFTERNOON INTO SAT MORNING. GFS AND ECMWF
SHOW THE SAME THING FRI AFTERNOON INTO SAT MORNING. WHAT THAT WILL
MEAN IS CHANCE POPS MOVING ACROSS THE CWA FRIDAY AFTERNOON THROUGH
FRIDAY NIGHT...THEN SATURDAY LOOKS DRY AS THE FRONT AND NARROW BAND
OF PCPN MOVE OUT. REMOVED POPS OVER THE EAST ON SATURDAY AS THE
FRONT IS WELL SOUTH AND EAST OF THE AREA BY THEN. THIS IS THE ONLY
CHANGE I MADE IN THE MID TERM. TEMPERATURES LOOKED GOOD AND LEFT
THEM ALONE FOR THE MOST PART.
IN THE EXTENDED...PROLONGED DRY PERIOD CONTINUES WITH THE NEXT
CHANCE FOR PCPN LATE ON TUESDAY. ECMWF SHOWS THE UPPER GREAT LAKES
STAYING IN A BROAD 500 MB TROUGH...BUT ALL THE DYNAMICS STAY NORTH
OF THE AREA UNTIL A TROUGH DIGS TO THE SOUTHEAST LATE ON TUESDAY.
TEMPERATURES THIS PERIOD LOOK TO BE NEAR NORMAL TO SLIGHTLY ABOVE
NORMAL WITH A SLOW WARMING TREND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 203 PM EDT WED MAY 9 2012
HIGH PRESSURE AND DRY AIR WILL BRING VFR CONDITIONS TO ALL TERMINALS
THROUGH THE PERIOD. ONLY SCT MID CLOUDS ARE EXPECTED INTO THURSDAY
MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 441 AM EDT WED MAY 9 2012
THE DENSE FOG OVER THE LAKE LOOKS TO BE DONE AS NO SHIP OBS OR
OBSERVATION HAVE SHOWN IT THE PAST FEW HOURS AND CARIBOU ISLAND HAS
A 6 DEGREE TEMP/DEW POINT SPREAD. THE DRIER AIR HAS MOVED OVER THE
LAKE AND HELPED TO DISSIPATE THE FOG. LACK OF SIGNIFICANT WEATHER
FEATURES WILL RESULT IN WINDS MOSTLY UNDER 20KT ACROSS LAKE SUPERIOR
THRU THE END OF THE WEEK. NO GALES SEEN ANYTIME SOON.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SYNOPSIS...ROLFSON
SHORT TERM...ROLFSON
LONG TERM...07
AVIATION...JLA
MARINE...07
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
204 PM EDT WED MAY 9 2012
.UPDATE...
ISSUED AT 919 AM EDT WED MAY 9 2012
FCST IN PRETTY GOOD SHAPE. ADDED FOG THROUGH 14Z OVR FAR WEST BUT
THIS IS FADING FAST. TWEAKED SKY COVER UP OVER EASTERN CWA FOR
MORNING AS THERMAL TROUGH /H85 TEMPS -2C/ SLIDES IN ON PERIPHERY
OF UPPER TROUGH MOVING ACROSS GREAT LAKES. RUC 900MB RH SHOWS THIS
WELL BUT ALSO INDICATES DAYTIME MIXING AND STABILIZING FLOW OFF LK
SUPERIOR WILL SIGNIFICANTLY DECREASE CLOUDS BY EARLY AFTN.
&&
.SYNOPSIS...
ISSUED AT 441 AM EDT WED MAY 9 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF OVER THE GULF OF
ALASKA...A DOWNSTREAM RIDGE EXTENDING FROM THE ROCKIES TO NUNAVUT
AND A TROF EXTENDING FROM QUEBEC THRU THE WRN GREAT LAKES. WITH A
SLOWLY PROGRESSIVE PATTERN...A QUIET 2-3 DAYS ARE ON THE WAY AS THE
UPSTREAM RIDGE SHIFTS E IN RESPONSE TO TROF MOVING INLAND FROM THE
GULF OF ALASKA. TROF WILL REACH THE UPPER LAKES LATE FRI...BRINGING
THE NEXT CHC OF -SHRA. AFTER A COOL DAY TODAY...A WARMING TREND WILL
GET UNDER WAY THU AND FRI AS WAA PATTERN DEVELOPS AHEAD OF THE TROF.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 441 AM EDT WED MAY 9 2012
WITH TROF AXIS SHIFTING SE OF UPPER MI...BACK EDGE OF
MOISTURE/CLOUDS IS PROGRESSING STEADILY SE ACROSS LAKE SUPERIOR
ATTM. PLENTY OF DRY AIR IN AN ABSOLUTE AND RELATIVE SENSE IS NOTED
UPSTREAM PER 00Z CWPL SOUNDING WHICH SHOWED PRECIPITABLE WATER OF
0.24 INCHES (AROUND 50PCT OF NORMAL) AND DWPT DEPRESSIONS GENERALLY
IN THE 10-25C RANGE FROM THE SFC TO ABOUT 500MB. WITH THE INFLUX OF
DRY AIR...THE FEW -SHRA/SPRINKLES NOTED ON KMQT RADAR WILL END IN
THE NEXT FEW HRS...AND CLOUDS WILL CLEAR OUT FROM NW TO SE TODAY. NOT
MUCH DIURNAL CU WAS NOTED UPSTREAM IN NRN ONTARIO YESTERDAY AFTN.
SHOULD BE A SIMILAR SITUATION HERE TODAY. THIS IDEA IS SUPPORTED BY
THE CU RULE WHICH SUGGESTS SCT DEVELOPMENT EARLIER IN THE DAY BEFORE
MIXING OF DRIER AIR BEGINS TO EAT AWAY AT THE CU. STABILIZING
INFLUENCE OF COOL FLOW OFF LAKE SUPERIOR WILL KEEP DAYTIME CU
INLAND...WITH CU PROGRESSIVELY FARTHER INLAND WITH TIME AS MARINE
LAYER INFLUENCE EXPANDS S. IT WILL BE A COOL DAY WITH 850MB
THERMAL TROF AROUND 0C SLOWLY SLIPPING E DURING THE AFTN. LOCATIONS
ALONG THE LAKE SUPERIOR SHORELINE SHOULD HOLD TO THE LOW/MID
40S...COOLEST OVER THE E. MIXING TO AROUND 800MB YIELDS MAX TEMPS IN
THE UPPER 50S/AROUND 60 TOWARD THE WI BORDER...WHICH IS INLINE WITH
UPSTREAM TEMPS IN NRN ONTARIO YESTERDAY.
AFTER A COOL DAY TODAY...STAGE WILL BE SET FOR A CHILLY/FROSTY
NIGHT TONIGHT AS SFC HIGH PRES RIDGE DRIFTS OVER THE AREA...
RESULTING IN WINDS DIMINISHING TO CALM/NEAR CALM UNDER MOSTLY CLEAR
SKIES. WITH PRECIPITABLE WATER RUNNING 50-75PCT OF NORMAL...
CONTINUED TO LEAN TOWARD THE LOW END OF AVBL GUIDANCE GIVEN THE
FAVORABLE RADIATIONAL COOLING CONDITIONS. TRADITIONAL COLD SPOTS IN
THE INTERIOR...ESPECIALLY W HALF...MAY SLIP INTO THE UPPER 20S. THAT
SAID...ONE POTENTIAL ISSUE THAT MAY LIMIT COOLING IS SOME CLOUD
COVER. MODELS SUGGEST THAT MID CLOUDS CURRENTLY OVER NRN MANITOBA AT
THE NOSE OF SOME WAA COULD DROP SE OVER THE AREA TONIGHT. SINCE THAT
WAA WEAKENS TO THE SE...EXPECT THE MID CLOUDS TO SHOW AT LEAST SOME
DECREASE IN COVERAGE AS THEY HEAD TOWARD THE AREA. OBVIOUSLY...CLOUD
TRENDS UPSTREAM TODAY WILL BE SOMETHING TO MONITOR DUE TO THE
POSSIBLE AFFECT ON MIN TEMPS TONIGHT.
UNDER SUNNY SKIES...A WARMER DAY IS EXPECTED THU WITH HIGH PRES IN
CONTROL AND 850MB TEMPS RISING TO 6 TO 10C BY LATE IN THE DAY. TEMPS
SHOULD REBOUND TO NEAR OR SLIGHTLY ABOVE NORMAL THOUGH LAKE BREEZES
SHOULD RULE LATE MORNING THRU THE AFTN TO PROVIDE COOLING NEAR THE
LAKES. MIXING UPWARDS OF 750MB YIELDS MAX TEMPS AROUND 70F OVER THE
INTERIOR W. TEMPS LAKESIDE WILL BE IN THE 40S/50S...DEPENDING ON HOW
EARLY LAKE BREEZE DEVELOPS AT EACH LOCATION.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 441 AM EDT WED MAY 9 2012
NAM SHOWS A 500 MB RIDGE OVER THE UPPER MISSISSIPPI RIVER VALLEY 00Z
FRI WITH TROUGHING AND A CLOSED LOW OVER NEW ENGLAND AND THE EASTERN
U.S...A CLOSED 500 MB LOW AND TROUGH NEAR IN NE MEXICO...AND A
TROUGH IN THE NORTHERN ROCKIES. THE 500 MB RIDGE MOVES INTO THE
UPPER GREAT LAKES ON FRIDAY. THE SHORTWAVE OVER THE NORTHERN ROCKIES
MOVES INTO THE UPPER GREAT LAKES FRIDAY NIGHT.
NAM BRINGS IN SOME 850-500 MB Q-VECTOR CONVERGENCE WITH DEEPER
MOISTURE MOVING IN FRI AFTERNOON INTO SAT MORNING. GFS AND ECMWF
SHOW THE SAME THING FRI AFTERNOON INTO SAT MORNING. WHAT THAT WILL
MEAN IS CHANCE POPS MOVING ACROSS THE CWA FRIDAY AFTERNOON THROUGH
FRIDAY NIGHT...THEN SATURDAY LOOKS DRY AS THE FRONT AND NARROW BAND
OF PCPN MOVE OUT. REMOVED POPS OVER THE EAST ON SATURDAY AS THE
FRONT IS WELL SOUTH AND EAST OF THE AREA BY THEN. THIS IS THE ONLY
CHANGE I MADE IN THE MID TERM. TEMPERATURES LOOKED GOOD AND LEFT
THEM ALONE FOR THE MOST PART.
IN THE EXTENDED...PROLONGED DRY PERIOD CONTINUES WITH THE NEXT
CHANCE FOR PCPN LATE ON TUESDAY. ECMWF SHOWS THE UPPER GREAT LAKES
STAYING IN A BROAD 500 MB TROUGH...BUT ALL THE DYNAMICS STAY NORTH
OF THE AREA UNTIL A TROUGH DIGS TO THE SOUTHEAST LATE ON TUESDAY.
TEMPERATURES THIS PERIOD LOOK TO BE NEAR NORMAL TO SLIGHTLY ABOVE
NORMAL WITH A SLOW WARMING TREND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 203 PM EDT WED MAY 9 2012
HIGH PRESSURE AND DRY AIR WILL BRING VFR CONDITIONS TO ALL TERMINALS
THROUGH THE PERIOD. ONLY SCT MID CLOUDS ARE EXPECTED INTO THURSDAY
MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 441 AM EDT WED MAY 9 2012
THE DENSE FOG OVER THE LAKE LOOKS TO BE DONE AS NO SHIP OBS OR
OBSERVATION HAVE SHOWN IT THE PAST FEW HOURS AND CARIBOU ISLAND HAS
A 6 DEGREE TEMP/DEW POINT SPREAD. THE DRIER AIR HAS MOVED OVER THE
LAKE AND HELPED TO DISSIPATE THE FOG. LACK OF SIGNIFICANT WEATHER
FEATURES WILL RESULT IN WINDS MOSTLY UNDER 20KT ACROSS LAKE SUPERIOR
THRU THE END OF THE WEEK. NO GALES SEEN ANYTIME SOON.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SYNOPSIS...ROLFSON
SHORT TERM...ROLFSON
LONG TERM...07
AVIATION...JLA
MARINE...07
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1236 PM CDT WED MAY 9 2012
.SHORT TERM...TODAY THROUGH FRIDAY
343 AM CDT WED MAY 9 2012
AT 3 AM...A TROUGH OF LOW PRESSURE WAS LOCATED JUST NORTH OF THE
INTERSTATE 90 CORRIDOR. THERE ARE A FEW SHOWERS STILL BEING
DETECTED BY RADAR JUST BEHIND THE TROUGH AXIS. NOT OVERLY
SURPRISED BY THIS...BECAUSE THE SAME THING WAS HAPPENING ACROSS
NORTHERN MINNESOTA ON TUESDAY MORNING. THE HRRR SUGGESTS THAT
THESE SHOWERS WILL DISSIPATE BY 09.12Z...SO KEPT THE FORECAST DRY
ACROSS THE AREA TODAY.
FOR TONIGHT AND EARLY THURSDAY MORNING...THE 09.00Z MODELS ARE IN
VERY GOOD AGREEMENT THAT THE 500 MB POTENTIAL VORTICITY ANOMALY
/CURRENTLY LOCATED OVER MONTANA/ WILL MOVE THROUGH THE FORECAST
AREA. THIS HAS BEEN A CONSISTENT SIGNAL OVER THE PAST COUPLE OF
DAYS. WITH MUCH OF THE MOISTURE ASSOCIATED WITH THIS SYSTEM IS
LOCATED ABOVE ABOVE 600 MB...ONLY EXPECTING A BROKEN DECK OF MID
AND HIGH CLOUDS. THESE CLOUDS WILL LIKELY LIMIT SOME OF NOCTURNAL
COOLING...SO RAISED THE TEMPERATURES BY A FEW DEGREES.
ON FRIDAY...ALL OF THE 09.00Z MODELS ARE IN VERY GOOD AGREEMENT
THAT A CANADIAN COLD FRONT WILL MOVE SOUTHEAST ACROSS
MINNESOTA...WESTERN IOWA...AND NORTHERN WISCONSIN. THIS FRONT WILL
HAVE LIMITED MOISTURE TO WORK DUE TO THE UPPER LEVEL LOW OVER TEXAS
PREVENTING THIS SYSTEM FROM TAPPING INTO GULF OF MEXICO MOISTURE.
WHILE THIS WILL BE CASE...MEAN LAYER CAPES STILL CLIMB INTO THE
500 TO 1000 J/KG RANGE AHEAD OF THIS FRONT. BUFKIT SOUNDINGS SHOW
THAT THERE WILL BE A CAP LOCATED BETWEEN 750 AND 650 MB. AS HAS
BEEN THE CASE OVER THE PAST SEVERAL DAYS...THE ECMWF CONTINUES TO
KEEP THE PRECIPITATION JUST WEST OF THE FORECAST AREA. MEANWHILE
THE GFS AND NAM/WRF HAVE COME AROUND TO GEM SOLUTION OF GENERATING
PRECIPITATION ACROSS THE ENTIRE AREA DURING THE AFTERNOON. THE
MAIN DIFFERENCE IS HOW FAST THE CAP ERODES. DUE TO THIS
UNCERTAINTY...JUST KEPT THE PRECIPITATION PROBABILITIES BETWEEN
25 AND 34 PERCENT. WITH WEAK 0-3 KM AND 0-6 KM SHEAR...IT STILL
DOES NOT LOOK LIKE THAT ANY OF THESE THUNDERSTORMS WOULD BECOME
SEVERE.
.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
343 AM CDT WED MAY 9 2012
ON FRIDAY NIGHT...ALL OF THE 09.00Z MODELS ARE IN FAIRLY GOOD
AGREEMENT THAT A COLD FRONT WILL MOVE SOUTHEAST THROUGH NORTHEAST
IOWA...AND SOUTHWEST AND CENTRAL WISCONSIN. THE INSTABILITY
GRADUALLY WANES DURING THE EVENING...THEREFORE...CONFINED THE
PRECIPITATION CHANCES TO MAINLY THE EVENING.
ON TUESDAY...THE LAST TWO RUNS OF THE ECMWF AND 09.00Z GFS
INDICATE THAT A WEAK SHORT WAVE TROUGH WILL MOVE SOUTHEAST ACROSS
NORTHERN MINNESOTA...NORTHERN WISCONSIN...AND SOUTHWEST ONTARIO.
OVERALL THE BEST FORCING WILL BE LOCATED TO THE NORTH AND EAST OF
THE FORECAST AREA. HOWEVER THE MEAN LAYER CAPES WILL RANGE FROM
500 TO 1000 J/JG...THIS WILL BE ENOUGH INSTABILITY FOR THE
POSSIBILITY OF SOME SCATTERED SHOWERS. THE 09.00Z GFS AND 08.12Z
ECMWF SUGGEST THAT THESE SHOWERS WOULD BE MAINLY NORTH OF
WISCONSIN 29. MEANWHILE THE 09.00Z ECMWF HAS THESE SHOWERS ACROSS
THE ENTIRE AREA. WITH THE BEST CONSISTENCY ACROSS TAYLOR AND
NORTHERN CLARK COUNTIES IN NORTH CENTRAL WISCONSIN...WENT WITH A
15 TO 24 PERCENT PRECIPITATION PROBABILITY AND LEFT THE REMAINDER
OF THE AREA DRY FOR NOW.
&&
.AVIATION...THROUGH 18Z THURSDAY
1236 PM CDT WED MAY 9 2012
DIURNAL CUMULUS WILL CONTINUE TO AFFECT THE TAF SITES THIS
AFTERNOON...WITH A SCT-BKN DECK BETWEEN 3K-4K FEET. THESE WILL
DISSIPATE THIS EVENING AS HIGH PRESSURE SETTLES ACROSS THE
AREA...WITH ONLY SOME CIRRUS SPILLING OVER THE UPPER LEVEL RIDGE.
BUFKIT SOUNDINGS INDICATING ENOUGH DRYING TO PRECLUDE MENTION OF
FOG LATE TONIGHT. AS HIGH PUSHES EAST THURSDAY...GRADIENT
TIGHTENS AS WINDS BECOME MORE SOUTHERLY AND MAY BE CLOSE TO 12
KNOTS AT KRST BETWEEN 15Z-18Z THURSDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
241 AM CDT WED MAY 9 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...RABERDING