Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/22/12

AREA FORECAST DISCUSSION

NWS TALLAHASSEE FL

 836 PM EDT Mon May 21 2012

.NEAR TERM [Rest of Tonight]...
The axis of instability across the western portion of our
forecast area is remaining very active into the evening hours.
Individual pulse cells that occurred early this afternoon are
giving way to a MCS propagating into the Florida panhandle from
Alabama. This activity has showed some signs of weakening due to
loss of afternoon heating. However, the HRRR model (which
initialized very well) seems to pivot yet another batch of
thunderstorm activity now in central Alabama through the western
and central portions of the area later tonight. Therefore, it
appears we may be in for an active night. Have adjusted the
current forecast to get more in line with this thinking. Although
the thunderstorm activity is expected to continue through
tonight, the threat of severe thunderstorms will diminish as
storms weaken overnight.

&&

.SHORT TERM [Tuesday through Wednesday Night]...
If ongoing conditions in SE Alabama are any indication of the type
of convection the current environment can support, we will certainly
have the potential for some severe weather tomorrow. The overall
setup will be similar to today: deep mixing to around 7000 ft, and a
sub-cloud inverted-V signature on forecast soundings. The main
difference will be about 1-2C of cooling in the mid-levels with the
approach of a digging shortwave, and increased flow to around 50kt
above 400mb. This may provide a slight increase in both mid-level
lapse rates and deep layer wind shear. The deep mixing is supportive
of primarily a damaging wind threat, and with 0-6km shear remaining
around 20-25 knots we should see a relatively short life cycle in
individual thunderstorm cells. Damaging winds will occur in the
collapsing cells with a fairly high downburst threat. However, we
probably won`t see updrafts sustained long enough to have an
appreciable large hail threat (cannot rule out a few 1" diameter
reports, though). SREF calibrated 12-hr severe probabilities from
the SPC website are anywhere from 15% to as high as 40% over parts
of our forecast area tomorrow. These values, combined with the
previously mentioned analysis, provide enough confidence to include
severe wording in the grids for Tuesday afternoon. Storms should
diminish in the evening, and we have a dry forecast after 06z Wed.

850mb temperatures actually rise about 1-2C as we move into
Wednesday, so we aren`t expecting much cooling as the surface front
stalls over the area and loses its character. Therefore, highs
should hit the lower 90s with mostly sunny skies.


.LONG TERM [Wednesday Night through next Monday]...
This extended period begins with a familiar pattern of closing off
an upper low over the mid- Atlantic states with troughing
extending down across the local region. The upper low and trough
will lift to the northeast on Friday followed by strong ridging
that will become centered over the Ohio valley but occupy the
eastern CONUS through the remainder of the period. At the
surface...a weak pattern will be in place with light winds across
the region through Friday. Then alight easterly flow becomes
established as high pressure ridges down from the northeast.
Overall, pattern will favor above normal temperatures with
afternoon highs into the lower to mid 90s along with generally dry
conditions for the latter part of the week. The easterly flow will
bring increasing low level moisture and possibly isolated
showers/thunderstorms to the area so went with 20% PoPs for Sunday
and Monday.


&&

.AVIATION [through 18z Tuesday]...
VFR conditions will prevail throughout much of the TAF cycle.
Scattered convection developing across East Central Alabama will
likely affect the DHN terminal after 21z when MVFR conditions in
TSRA will be possible. Expect convection to largely diminish after
sunset. Aside from a brief MVFR vsby restriction at VLD before
sunrise, no other impacts are anticipated this TAF cycle.

&&

.MARINE...
West to southwest flow around 10 knots will prevail over the NE Gulf
of Mexico over the next few days, with seas around 1-2 feet. No
cautionary or advisory level conditions are expected until at least
late on Saturday or early on Sunday.

&&

.FIRE WEATHER...
With the dry air fairly well entrenched across much of the
interior the Florida Big Bend and Panhandle this afternoon, the
present Red Flag Warning over Washington, Inland Bay, Leon, and
Inland Wakulla Counties (where the ERC is also greater than 35) is
well on track towards verification (4 hour minimum durations). We
are expecting slightly more humid conditions on Tuesday, which
should keep minimum Relative Humidities just above 35 percent
across North Florida, but this will have to be monitored very
closely, as the combination of ERCs and Dispersions would
otherwise be favorable for Red Flag Conditions. On Wednesday, did
go ahead with a new Fire Weather Watch for the Interior Florida
Big Bend and Panhandle zones, for the possibility of Relative
Humidities less than 35 percent combined with Dispersions greater
than 75 and ERCs greater than 20.

&&

.PRELIMINARY POINT TEMPS/POPS...
Tallahassee   64  90  65  91  65 /  20  40  20  10   0
Panama City   71  86  70  86  71 /  20  20  10  10   0
Dothan        65  89  63  91  65 /  30  40  10  10   0
Albany        65  89  63  91  64 /  30  50  20  10   0
Valdosta      64  92  63  89  64 /  20  40  30  10   0
Cross City    64  90  63  90  64 /  10  10  10  10   0
Apalachicola  67  85  70  85  71 /  20  20  10  10   0

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
AL...None.
GA...None.
FL...Fire Weather Watch from Wednesday afternoon through Wednesday
     evening for Calhoun-Gadsden-Holmes-Inland Jefferson-Inland
     Walton-Jackson-Lafayette-Leon-Liberty-Madison-Washington.

     Red Flag Warning until 7 PM EDT /6 PM CDT/ this evening for
     Inland Bay-Inland Wakulla-Leon-Washington.

GM...None.

&&

$$

Near Term...Lericos
Short Term...Lamers
Long Term...Barry
Aviation...Gosdey
Marine...Lamers
Fire Weather...Gould









AREA FORECAST DISCUSSION...RETRANSMITTED...

NWS QUAD CITIES IA IL

 641 AM CDT SUN MAY 20 2012

.UPDATE...
TRENDS IN SATELLITE/RADAR AND THE RAP MODEL NOW QUESTION IF
ANYTHING OTHER THAN SPRINKLES WILL OCCUR DURING THE MORNING HOURS.
RAP TRENDS ALSO INDICATE THE OVERALL FORCING WITH THE FRONT IS
WEAK BUT IT WILL BE MOVING ACROSS THE CWFA DURING PEAK HEATING.
MCS...LIFT...AND HEAVY RAIN TOOLS ALONG WITH THE OVERALL SYNOPTIC
FORCING SUGGEST CONVECTION MAY BE POSSIBLE THIS AFTERNOON WITH
DEVELOPMENT GENERALLY EAST OF THE MISSISSIPPI WHERE TEMPERATURES
WILL BE THE WARMEST. FCST SOUNDINGS FROM THE RAP ARE SUGGESTING
CONVECTIVE TEMPERATURES ARE AROUND 90 WHICH MAY NOT BE ACHIEVABLE
DUE TO CLOUD COVER.

WILL CONTINUE TO MONITOR TRENDS FOR A POSSIBLE UPDATE PRIOR TO 8
AM.             ..08..

&&

.AVIATION...
COLD FRONT WILL MOVE THROUGH EASTERN IOWA/NORTHERN ILLINOIS AFT
18Z/20. VFR WX IS STILL GENERALLY EXPECTED AT ALL TAF SITES.
CONVECTION IS STILL IN QUESTION THIS AFTERNOON BUT TRENDS FROM THE
RAP MODEL SUGGEST IT WOULD OCCUR EAST OF KMLI/KBRL. SATELLITE
TRENDS INDICATE MVFR CONDITIONS DVLPG BEHIND THE FRONT WHICH
SHOULD AFFECT KCID/KDBQ AFT 21Z/20. HIGH PRESSURE BUILDING IN AFT
00Z/21 WILL EVENTUALLY ALLOW VFR CONDITIONS TO DVLP AGAIN BY
12Z/21 AT ALL TAF SITES.             ..08..

&&

.PREV DISCUSSION... /ISSUED 327 AM CDT SUN MAY 20 2012/

SYNOPSIS...
06Z SFC ANALYSIS HAS A LOW IN SOUTHERN MINNESOTA WITH AN INFERRED
LOW JUST EAST OF KOFF. THE FRONTAL BOUNDARY CONNECTS WITH THE
SOUTHERN MINNESOTA LOW INTO CENTRAL KANSAS WHILE ANOTHER COLD
FRONT EXTENDED FROM THE KOFF LOW THROUGH EASTERN KANSAS AND INTO
WEST TEXAS. DEW POINTS AHEAD OF THE FRONTAL BOUNDARY WERE IN THE
50S WITH POCKETS OF LOW 60 DEW POINTS. BEHIND THE FRONT DEW POINTS
QUICKLY DROPPED OFF INTO THE 40S WITH SOME 30S IN THE FRONT RANGE
OF THE ROCKIES. SATELLITE/RADAR TRENDS SHOW THE PRECIPITATION
CONTINUING TO DECREASE ACROSS THE MIDWEST AS CLOUD TOPS WARM.

SHORT TERM...TODAY AND TONIGHT...
THE OVERALL FORCING ALONG THE FRONTAL BOUNDARY IS NOT GREAT WHICH
BRINGS INTO QUESTION THE POTENTIAL FOR PRECIPITATION THIS
AFTERNOON. CLOUD COVER MAY KEEP TEMPERATURES BELOW THE CONVECTIVE
TEMPERATURE. BASED ON CURRENT RADAR/SATELLITE TRENDS ALONG WITH
INPUT FROM THE RAP...WILL GO WITH SCHC POPS IN THE WESTERN 40
PERCENT OF THE CWFA THIS MORNING FOR ISOLATED SHOWERS. THE LIFT
TOOL SHOWS THE OVERALL CONVERGENCE CONTINUING TO WEAKEN SO
SPRINKLES MAY BE MORE APPROPRIATE THAN ISOLATED SHRA.

THIS AFTERNOON...ONCE THE COLD FRONT PASSES ANY PARTICULAR
LOCATION THE THREAT FOR ANY PRECIPITATION IS OVER. BASED ON
OBSERVATIONS AND INPUT FROM THE RAP...ROUGHLY THE EASTERN HALF TO
TWO THIRDS OF THE CWFA WILL HAVE A CHANCE FOR PRECIPITATION THIS
AFTERNOON. THE WEAK FORCING AND QUESTIONS ABOUT ACHIEVING
CONVECTIVE TEMPERATURE HAS RESULTED IN POPS BEING LOWERED. THE
EASTERN THIRD OF THE CWFA PROBABLY HAS THE BEST CHANCE AT SEEING
SOME SCATTERED SHRA/TSRA. THE CAA BEHIND THE FRONT IS QUITE STRONG
AS THE OVERALL SYSTEM CONTINUES TO STRENGTHEN SO TEMPERATURES
SHOULD SLOWLY FALL DURING THE AFTERNOON IN THE WESTERN PARTS OF
THE CWFA.

TONIGHT...LINGERING SHRA WILL END AROUND SUNSET IN THE FAR EASTERN
PARTS OF THE CWFA WHILE DRY CONDITIONS ARE EXPECTED ELSEWHERE.
SKIES WILL CLEAR FROM WEST TO EAST OVERNIGHT RESULTING IN A CHILLY
NIGHT. IT IS WITHIN THE REALM OF POSSIBILITY THAT FAVORED AREAS IN
THE NORTHWEST PART OF THE CWFA MAY DROP INTO THE LOWER 40S BEFORE
SUNRISE MONDAY.                  ..08..

LONG TERM...MONDAY THROUGH SATURDAY...
THE PERIOD FROM MONDAY INTO TUESDAY NIGHT APPEARS TO BE PREDICTABLY
QUIET AND PLEASANT WITH WIDE DIURNAL TEMPERATURE RANGES. AFTER A
CHILLY START TO THE DAY MONDAY...DEEP MIXING AND SUNSHINE WILL HELP
BOOST READINGS BACK TO THE LOWER 70S OVER THE CWA...WITH SOME
POSSIBLE MID 70S FAR SOUTH AND WEST.   HIGH PRESSURE AND DRY AIR IN
PLACE MONDAY NIGHT WILL ALLOW FOR LOWS IN THE UPPER 40S TO LOWER
50S...WITH SOME LOCAL COLD SPOTS POSSIBLY DIPPING TO THE MID 40S.
MODERATION ALOFT BY TUESDAY SHOULD HELP JUMP WESTERN 1/2
TEMPERATURES INTO THE UPPER 70S TO LOWER 80S...WHILE THE EAST SEES
HIGHS IN THE MID 70S. WEDNESDAY THROUGH THURSDAY...HEAT WILL
CERTAINLY BUILD...WITH HIGHS IN THE LOWER TO UPPER 80S.

THE PATTERN MUCH DEBATED IN THE EXTENDED HAS BEEN THE POSITION OF A
LARGE SYNOPTIC RIDGE...AND THE CLOSENESS...OR LACK THERE OF OF A
BROAD WESTERN TROF...AS WELL AS JET ENERGY. THE DIFFERENCE BETWEEN
THE TWO HAS BEEN THE GFS/UKMET CAMP OF EPISODES OF THUNDERSTORMS
WITH A FRONT NEARBY...OF THE ECMWF/GEM CAMP SHOWING SUPER STRONG
UPPER RIDGING AND INTENSE MIDWEST HEAT.  TONIGHTS 00Z MODELS ARE IN
BETTER AGREEMENT...AND THERE IS HOPE THAT CONFIDENCE ON A PATTERN IS
GOING UP. THE GFS AND EC CAMPS ARE NOW IN APPROXIMATE AGREEMENT WITH
THE FRONT NEARING THE CWA TOWARDS THURSDAY...AND REMAINING INTO
FRIDAY NIGHT. CONVECTION IS POSSIBLE...BUT ALSO MAY DEAL WITH STRONG
CAPPING. THUS...WE WILL SHOW A SLIGHT CHANCE FOR STORMS IN THE LATE
WEEK. TEMPERATURES SHOULD BE WARM THROUGH SATURDAY...AND IF THE
RIDGE CAN BUILD AS SHOWN BY THE EC SATURDAY...WE WILL BE HOT THIS
HOLIDAY WEEKEND.  ERVIN

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&

$$







AREA FORECAST DISCUSSION

NWS GOODLAND KS

 826 PM MDT MON MAY 21 2012

.UPDATE...
ISSUED AT 822 PM MDT MON MAY 21 2012

INCREASED PRECIPITATION CHANCES OVER PART OF SOUTHWEST NEBRASKA AS
A THUNDERSTORM APPROACHES THE AREA. STORM SHOULD EXIT THE
SOUTHWEST NEBRASKA AND FAR NORTHWEST KANSAS AROUND MIDNIGHT ASSUMING IT
WILL AT CONTINUE AT ITS CURRENT RATE OF SPEED AND DIRECTION.

UPDATE ISSUED AT 739 PM MDT MON MAY 21 2012

HAVE REMOVED PRECIP. CHANCES FOR THE NIGHT FOR THE AREA AND HAVE
SPED UP THE START TIME OF THE PATCHY FOG AFTER MIDNIGHT.

VISIBLE/IR SATELLITE INDICATES CUMULUS COVERAGE HAS BEEN
DISSIPATING FOR THE LAST HOUR OR SO AND MODEL ANALYSIS SHOWS THE
MID LEVEL CAPE MOVING SOUTH OUT OF THE AREA. OVERNIGHT MODELS
CONTINUE TO HAVE THE MID LEVEL CAPE SOUTH OF THE AREA. SOME 5O0MB
VORTICITY DOES DEVELOP OVER THE SOUTHERN PART OF THE AREA...BUT
POINT SOUNDINGS SHOW THE ENVIRONMENT DRYING OUT THROUGH THE
EVENING INTO THE OVERNIGHT PERIODS AS THE MID LEVEL WINDS TURN
TO THE SOUTHWEST.

LATEST RUC ANALYSIS OF MIXING RATIOS/MOISTURE TRANS. VECTORS AT
THE SURFACE IS MOVING THE HIGHER MIXING RATIOS INTO THE AREA
EARLIER. POINT SOUNDINGS ACROSS THE SOUTHERN PART OF THE AREA
CONTINUE TO ADVERTISE SATURATION NEAR THE GROUND. HOWEVER MODELS
DISAGREE HOW LONG THE SATURATION WILL LAST AND HOW DEEP IT WILL
BE. THE FAIRLY BREEZY SOUTH WINDS ARE ALSO A CONCERN FOR FOG
DEVELOPMENT. AS SUCH WILL LEAVE THE FOG COVERAGE AT PATCHY FOR NOW.

&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 121 PM MDT MON MAY 21 2012

16Z WATER VAPOR IMAGERY/RUC ANALYSIS INDICATED BROAD RIDGING IN
PLACE ACROSS THE CENTRAL ROCKIES AND ADJACENT HIGH PLAINS...WITH
TROUGH APPROACHING THE PACIFIC NORTHWEST. AT THE SFC...TROUGH WAS IN
PLACE ACROSS CENTRAL AND EASTERN COLORADO ...ROUGHLY BETWEEN KDNR
AND KAKO. TO THE EAST OF THIS TROUGH...MOISTURE ADVECTION WAS
INCREASING WITH AN AREA OF DEW POINTS AT OR ABOVE 50 F FROM KLIC
SOUTHEAST INTO THE OKLAHOMA PANHANDLE. 12Z RAOBS AT DNR AND DDC
INDICATED AREA OF STEEP MID LEVEL LAPSE RATES BETWEEN H7 AND
H6...WITH A MUCH DEEPER LAYER NOTED AT DNR.

MAIN CONCERN FOR THE SHORT TERM PERIODS WILL BE CONVECTIVE
INITIATION CHANCES TODAY AND TEMPS/RH/FIRE WX TOMORROW.

REST OF THE AFTERNOON-TONIGHT...WITH AFOREMENTIONED MOISTURE
ADVECTION ALREADY ONGOING PER SFC OBS...AND NOSE OF STEEP MID LEVEL
LAPSE RATES IN PLACE ALONG SFC TROUGH ACROSS EASTERN COLORADO
CONFIDENCE INCREASING IN CONVECTIVE INITIATION ALONG SFC TROUGH THIS
AFTERNOON...ESPECIALLY GIVEN THAT MIXED LAYER TDS ARE VERY SIMILAR
TO FORECAST SFC VALUES INDICATING SOME DEPTH TO THE MOISTURE
PROFILE. WHILE CONFIDENCE IN DEVELOPMENT OF THUNDERSTORMS IS
HIGHER...HIGHER RES MODELS KEEPING COVERAGE FAIRLY SPARSE AND WITH
LATEST HRRR JUMPING AROUND QUITE A BIT WITH TIMING AND LOCATION...DO
NOT THINK POPS ABOVE THE 20-30 PERCENT RANGE WARRANTED JUST YET.
WITH A LOT OF UNCERTAINTY IN THE DETAILS...HAVE GENERALLY WENT WITH
BROADER COVERAGE OF POPS STARTING FIRST AROUND SFC TROUGH AROUND 20Z
AND GRADUALLY SHIFTING EAST AND DIMINISHING. SOME ELEVATED
INSTABILITY REMAINS THROUGH THE NIGHT WITH SOME WEAK ASCENT EXPECTED
TO THE WEST OF H7 THERMAL RIDGE. PROBABILISTIC GUIDANCE NOT REALLY
SUPPORTING MUCH OF A PRECIP THREAT AT THIS POINT...BUT CANNOT
TOTALLY RULE OUT SOME ELEVATED OVERNIGHT STORMS AND WILL GENERALLY
KEEP PREVIOUS FORECAST IN THIS REGARD. GIVEN ALREADY OBSERVED
MOISTURE TRANSPORT...DO HAVE SOME CONCERNS ABOUT THE DEVELOPMENT OF
FOG OVERNIGHT. WINDS SHOULD GENERALLY STAY UP WHICH WILL MINIMIZE
THE THREAT SOME WHAT...BUT GIVEN EXPECTED MOISTURE PROFILE AND SREF
INDICATING A SMALL THREAT FOR FOG THINK AT LEAST A PATCHY MENTION IS
IN ORDER.

TUESDAY...H5 RIDGE AXIS WILL SHIFT TO THE EAST THROUGH THE
DAY...WITH CWA UNDER THE INFLUENCE OF LARGE SCALE FORCING FOR
SUBSIDENCE THROUGH MUCH OF THE DAY. WHILE SYNOPTIC SCALE SUPPORT IS
LACKING...FAIRLY STRONG AND PERSISTENT CONVERGENCE EXPECTED ALONG
DRY LINE THAT WILL DEVELOP ACROSS AREA DURING THE AFTERNOON. COULD
POTENTIALLY SEE A STORM OR TWO DEVELOP IN THIS AREA...BUT GIVEN
LARGE SCALE PATTERN...POTENTIAL FOR A STRONG CAP AND VERY LOW
PROBABILITIES FROM THE NORMALLY WET SREF DATABASE...CONFIDENCE NOT
HIGH ENOUGH TO INCLUDE THUNDERSTORM THREAT AT THIS TIME. MIXED LAYER
TEMPS STILL SUPPORT TEMPS IN THE 90S ACROSS MUCH OF THE
AREA...ALTHOUGH THERE DOES APPEAR TO BE SOME DISCREPANCIES FOR HOW
WARM THINGS WILL GET WITH SREF INDICATING A RANGE BETWEEN 97 AND
AROUND 88 FOR GLD. GIVEN OVERALL PATTERN AND POTENTIAL TO BE ON MUCH
DRIER SIDE OF THE DRY LINE THINK WARMER SOLUTIONS THE WAY TO AND MADE
ONLY MINOR CHANGES TO GOING FORECAST.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 236 PM MDT MON MAY 21 2012

A COLD FRONT WILL DROP SOUTH TOWARDS OUR CWA TUESDAY NIGHT AS A
SHORTWAVE TROUGH MOVES ACROSS THE NORTHERN PLAINS. WITH AIR MASS OVER
CWA GENERALLY STABILIZING TUESDAY EVENING THUNDERSTORM CHANCES
REMAIN MINIMAL AND WILL BE TIED MAINLY TO WHAT DEVELOPS DURING THE
AFTERNOON. MODEL DIFFERENCES IN THE TIMING/POSITION OF THE FRONT
WILL HAVE A LARGER IMPACT ON THE TEMPERATURE FORECAST WEDNESDAY WHEN
IT WILL STALL OVER THE CWA AND THEN LIFT NORTH AS A WARM FRONT.
ECMWF AND GFS TEND TO BE THE QUICKEST IN DEVELOPING A STRONG LEE
TROUGH OVER EASTERN COLORADO...PUSHING THE FRONT NORTH BY MIDDAY.
CURRENT HIGH TEMP FORECAST FOR WEDNESDAY REFLECTS A BLEND OF
SOLUTIONS WITH UPPER 90S OVER SW PART OF THE CWA...AND UPPER 70S IN
THE NORTHWEST. WERE THE FRONT TO LIFT QUICKER...MID-UPPER 90S COULD
BE EXPECTED ACROSS A MUCH LARGER PART OF THE CWA. WITH THE SURFACE
TROUGH EXPECTED TO BE OVER THE CWA BY MIDDAY...STRONGEST SURFACE
GRADIENT SHOULD REMAIN EAST...SO WINDS SHOULD REMAIN BELOW RED FLAG
CRITERIA.

LARGE SCALE TROUGH DEVELOPS OVER THE GREAT BASIN/NORTHERN ROCKIES BY
WEDNESDAY AFTERNOON...WITH A SERIES OF WEAK SHORTWAVE TROUGH MOVING
JUST NORTH AND WEST OF THE CWA THROUGH NEXT WEEKEND. THE FIRST
SHORTWAVE ARRIVES BY WEDNESDAY NIGHT...WITH THUNDERSTORMS POSSIBLY
INITIATING OVER NORTHEAST COLORADO. BEST CHANCES WILL BE ACROSS THE
NORTH AFTER MIDNIGHT WEDNESDAY NIGHT WHEN A COLD FRONT WILL MOVE
INTO SOUTHWEST NEBRASKA AND STALL. I HAVE LESS CONFIDENCE FURTHER
SOUTH AND EAST...HOWEVER WITH AT LEAST SOME GUIDANCE SHOWING
DEVELOPMENT TOWARDS THE I-70 CORRIDOR...I FELT COMFORTABLE KEEPING
SLIGHT CHANCE/CHANCE POPS IN PLACE.

BY THURSDAY THIS INITIAL SHORTWAVE WILL MOVE TO THE EAST WITH
SUBSIDENCE BUILDING IN OVER THE CWA IN IT WAKE. AT THE SAME TIME
ANOTHER WEAK DISTURBANCE WILL BE MOVING IN FROM THE WEST BY THURSDAY
AFTERNOON/NIGHT...WITH POPS INCREASING ONCE AGAIN FROM THE
WEST...AND CHANCES LIMITED TO NORTH OF INTERSTATE 70.

FRIDAY-MONDAY...LARGE SCALE TROUGH REMAINS IN PLACE ACROSS THE
WESTERN CONUS...EVENTUALLY BREAKING DOWN AND TRANSITIONING TO A
WESTERLY ZONAL PATTERN BY EARLY NEXT WEEK. RESULT WILL BE A FAIRLY
ACTIVE PATTERN...WITH STORM TRACK FAVORING NORTHERN PORTIONS OF OUR
CWA FOR SHOWER/THUNDERSTORM CHANCES. CONFIDENCE WAS TOO LOW TO RAISE
POPS BEYOND 20/30 RANGE...CONSIDERING DIFFERENCE IN TIMING OF THESE
FEATURES...AND DIFFERENCES IN POSITION OF SURFACE FEATURES AS
HANDLED BY GUIDANCE.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 521 PM MDT MON MAY 21 2012

VFR CONDITIONS ARE FORECAST FOR THE 0Z TAFS. ISOLATED
THUNDERSTORMS WILL CONTINUE TO FORM EAST OF A SURFACE TROUGH OVER
EASTERN COLORADO THROUGH THE EARLY EVENING. MODEL ANALYSIS OF THE
ENVIRONMENT SHOWS THE CONVECTIVE INSTABILITY TAPERING OFF TOWARD KGLD...SO
DO NOT EXPECT THE ISOLATED THUNDERSTORMS TO LAST ONCE THEY MOVE
INTO KANSAS. EXPECT STORMS TO REMAIN NORTH OF KMCK THROUGH THE
EVENING AS THEY TRACK EAST. OTHERWISE THE GUSTY SOUTH WINDS WILL
DECLINE DURING THE EVENING...BUT REMAIN BREEZY THROUGH THE NIGHT.
THERE IS THE POTENTIAL FOR IFR CEILINGS/FOG AT KGLD DURING THE
EARLY MORNING HOURS. HOWEVER MODELS DISAGREE WITH WHETHER THE LOW
LEVELS WILL SATURATE ENOUGH TO DEVELOP A BROKEN CLOUD DECK...SO
WILL LEAVE A SCATTERED DECK FOR NOW AT KGLD. AM NOT TOO CONFIDENT
WITH THE DEVELOPMENT OF FOG EITHER. KGLD SEEMS TO BE ON THE
NORTHERN END OF THE FOG AS IT DEVELOPS MORE TO THE SOUTH. WITH THE
BREEZY WINDS DURING THAT TIME AND THE BRIEF PERIOD OF LOW LEVEL SATURATION
IN THE SOUNDINGS...WILL HOLD OFF UNTIL NEXT TAF ISSUANCE BEFORE
GOING LOWER THAN VFR FOR VIS.


&&

.FIRE WEATHER...
ISSUED AT 121 PM MDT MON MAY 21 2012

VERY WARM AND DRY WEATHER IS EXPECTED ACROSS MUCH OF THE AREA ON
TUESDAY...WITH AFTERNOON HUMIDITIES BELOW 15 PERCENT EXPECTED
ALONG AND EAST OF THE COLORADO AND KANSAS STATE LINE. WESTERLY
WINDS WILL GRADUALLY INCREASE IN THIS AREA TO AROUND 15 MPH IN THE
AFTERNOON. WITH RECENT RAINFALL AND WINDS NOT EXPECTED TO INCREASE
TO LATE IN THE AFTERNOON...OVERALL CONFIDENCE IN CRITICAL FIRE
WEATHER CONDITIONS IS TOO LOW TO WARRANT A WATCH OR WARNING AT
THIS POINT.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&

$$

UPDATE...JTL
SHORT TERM...JRM
LONG TERM...DR
AVIATION...JTL
FIRE WEATHER...JRM







AREA FORECAST DISCUSSION

NWS GOODLAND KS

 749 PM MDT MON MAY 21 2012

.UPDATE...
ISSUED AT 739 PM MDT MON MAY 21 2012

HAVE REMOVED PRECIP. CHANCES FOR THE NIGHT FOR THE AREA AND HAVE
SPED UP THE START TIME OF THE PATCHY FOG AFTER MIDNIGHT.

VISIBLE/IR SATELLITE INDICATES CUMULUS COVERAGE HAS BEEN
DISSIPATING FOR THE LAST HOUR OR SO AND MODEL ANALYSIS SHOWS THE
MID LEVEL CAPE MOVING SOUTH OUT OF THE AREA. OVERNIGHT MODELS
CONTINUE TO HAVE THE MID LEVEL CAPE SOUTH OF THE AREA. SOME 5O0MB
VORTICITY DOES DEVELOP OVER THE SOUTHERN PART OF THE AREA...BUT
POINT SOUNDINGS SHOW THE ENVIRONMENT DRYING OUT THROUGH THE
EVENING INTO THE OVERNIGHT PERIODS AS THE MID LEVEL WINDS TURN
TO THE SOUTHWEST.

LATEST RUC ANALYSIS OF MIXING RATIOS/MOISTURE TRANS. VECTORS AT
THE SURFACE IS MOVING THE HIGHER MIXING RATIOS INTO THE AREA
EARLIER. POINT SOUNDINGS ACROSS THE SOUTHERN PART OF THE AREA
CONTINUE TO ADVERTISE SATURATION NEAR THE GROUND. HOWEVER MODELS
DISAGREE HOW LONG THE SATURATION WILL LAST AND HOW DEEP IT WILL
BE. THE FAIRLY BREEZY SOUTH WINDS ARE ALSO A CONCERN FOR FOG
DEVELOPMENT. AS SUCH WILL LEAVE THE FOG COVERAGE AT PATCHY FOR NOW.

&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 121 PM MDT MON MAY 21 2012

16Z WATER VAPOR IMAGERY/RUC ANALYSIS INDICATED BROAD RIDGING IN
PLACE ACROSS THE CENTRAL ROCKIES AND ADJACENT HIGH PLAINS...WITH
TROUGH APPROACHING THE PACIFIC NORTHWEST. AT THE SFC...TROUGH WAS IN
PLACE ACROSS CENTRAL AND EASTERN COLORADO ...ROUGHLY BETWEEN KDNR
AND KAKO. TO THE EAST OF THIS TROUGH...MOISTURE ADVECTION WAS
INCREASING WITH AN AREA OF DEW POINTS AT OR ABOVE 50 F FROM KLIC
SOUTHEAST INTO THE OKLAHOMA PANHANDLE. 12Z RAOBS AT DNR AND DDC
INDICATED AREA OF STEEP MID LEVEL LAPSE RATES BETWEEN H7 AND
H6...WITH A MUCH DEEPER LAYER NOTED AT DNR.

MAIN CONCERN FOR THE SHORT TERM PERIODS WILL BE CONVECTIVE
INITIATION CHANCES TODAY AND TEMPS/RH/FIRE WX TOMORROW.

REST OF THE AFTERNOON-TONIGHT...WITH AFOREMENTIONED MOISTURE
ADVECTION ALREADY ONGOING PER SFC OBS...AND NOSE OF STEEP MID LEVEL
LAPSE RATES IN PLACE ALONG SFC TROUGH ACROSS EASTERN COLORADO
CONFIDENCE INCREASING IN CONVECTIVE INITIATION ALONG SFC TROUGH THIS
AFTERNOON...ESPECIALLY GIVEN THAT MIXED LAYER TDS ARE VERY SIMILAR
TO FORECAST SFC VALUES INDICATING SOME DEPTH TO THE MOISTURE
PROFILE. WHILE CONFIDENCE IN DEVELOPMENT OF THUNDERSTORMS IS
HIGHER...HIGHER RES MODELS KEEPING COVERAGE FAIRLY SPARSE AND WITH
LATEST HRRR JUMPING AROUND QUITE A BIT WITH TIMING AND LOCATION...DO
NOT THINK POPS ABOVE THE 20-30 PERCENT RANGE WARRANTED JUST YET.
WITH A LOT OF UNCERTAINTY IN THE DETAILS...HAVE GENERALLY WENT WITH
BROADER COVERAGE OF POPS STARTING FIRST AROUND SFC TROUGH AROUND 20Z
AND GRADUALLY SHIFTING EAST AND DIMINISHING. SOME ELEVATED
INSTABILITY REMAINS THROUGH THE NIGHT WITH SOME WEAK ASCENT EXPECTED
TO THE WEST OF H7 THERMAL RIDGE. PROBABILISTIC GUIDANCE NOT REALLY
SUPPORTING MUCH OF A PRECIP THREAT AT THIS POINT...BUT CANNOT
TOTALLY RULE OUT SOME ELEVATED OVERNIGHT STORMS AND WILL GENERALLY
KEEP PREVIOUS FORECAST IN THIS REGARD. GIVEN ALREADY OBSERVED
MOISTURE TRANSPORT...DO HAVE SOME CONCERNS ABOUT THE DEVELOPMENT OF
FOG OVERNIGHT. WINDS SHOULD GENERALLY STAY UP WHICH WILL MINIMIZE
THE THREAT SOME WHAT...BUT GIVEN EXPECTED MOISTURE PROFILE AND SREF
INDICATING A SMALL THREAT FOR FOG THINK AT LEAST A PATCHY MENTION IS
IN ORDER.

TUESDAY...H5 RIDGE AXIS WILL SHIFT TO THE EAST THROUGH THE
DAY...WITH CWA UNDER THE INFLUENCE OF LARGE SCALE FORCING FOR
SUBSIDENCE THROUGH MUCH OF THE DAY. WHILE SYNOPTIC SCALE SUPPORT IS
LACKING...FAIRLY STRONG AND PERSISTENT CONVERGENCE EXPECTED ALONG
DRY LINE THAT WILL DEVELOP ACROSS AREA DURING THE AFTERNOON. COULD
POTENTIALLY SEE A STORM OR TWO DEVELOP IN THIS AREA...BUT GIVEN
LARGE SCALE PATTERN...POTENTIAL FOR A STRONG CAP AND VERY LOW
PROBABILITIES FROM THE NORMALLY WET SREF DATABASE...CONFIDENCE NOT
HIGH ENOUGH TO INCLUDE THUNDERSTORM THREAT AT THIS TIME. MIXED LAYER
TEMPS STILL SUPPORT TEMPS IN THE 90S ACROSS MUCH OF THE
AREA...ALTHOUGH THERE DOES APPEAR TO BE SOME DISCREPANCIES FOR HOW
WARM THINGS WILL GET WITH SREF INDICATING A RANGE BETWEEN 97 AND
AROUND 88 FOR GLD. GIVEN OVERALL PATTERN AND POTENTIAL TO BE ON MUCH
DRIER SIDE OF THE DRY LINE THINK WARMER SOLUTIONS THE WAY TO AND MADE
ONLY MINOR CHANGES TO GOING FORECAST.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 236 PM MDT MON MAY 21 2012

A COLD FRONT WILL DROP SOUTH TOWARDS OUR CWA TUESDAY NIGHT AS A
SHORTWAVE TROUGH MOVES ACROSS THE NORTHERN PLAINS. WITH AIR MASS OVER
CWA GENERALLY STABILIZING TUESDAY EVENING THUNDERSTORM CHANCES
REMAIN MINIMAL AND WILL BE TIED MAINLY TO WHAT DEVELOPS DURING THE
AFTERNOON. MODEL DIFFERENCES IN THE TIMING/POSITION OF THE FRONT
WILL HAVE A LARGER IMPACT ON THE TEMPERATURE FORECAST WEDNESDAY WHEN
IT WILL STALL OVER THE CWA AND THEN LIFT NORTH AS A WARM FRONT.
ECMWF AND GFS TEND TO BE THE QUICKEST IN DEVELOPING A STRONG LEE
TROUGH OVER EASTERN COLORADO...PUSHING THE FRONT NORTH BY MIDDAY.
CURRENT HIGH TEMP FORECAST FOR WEDNESDAY REFLECTS A BLEND OF
SOLUTIONS WITH UPPER 90S OVER SW PART OF THE CWA...AND UPPER 70S IN
THE NORTHWEST. WERE THE FRONT TO LIFT QUICKER...MID-UPPER 90S COULD
BE EXPECTED ACROSS A MUCH LARGER PART OF THE CWA. WITH THE SURFACE
TROUGH EXPECTED TO BE OVER THE CWA BY MIDDAY...STRONGEST SURFACE
GRADIENT SHOULD REMAIN EAST...SO WINDS SHOULD REMAIN BELOW RED FLAG
CRITERIA.

LARGE SCALE TROUGH DEVELOPS OVER THE GREAT BASIN/NORTHERN ROCKIES BY
WEDNESDAY AFTERNOON...WITH A SERIES OF WEAK SHORTWAVE TROUGH MOVING
JUST NORTH AND WEST OF THE CWA THROUGH NEXT WEEKEND. THE FIRST
SHORTWAVE ARRIVES BY WEDNESDAY NIGHT...WITH THUNDERSTORMS POSSIBLY
INITIATING OVER NORTHEAST COLORADO. BEST CHANCES WILL BE ACROSS THE
NORTH AFTER MIDNIGHT WEDNESDAY NIGHT WHEN A COLD FRONT WILL MOVE
INTO SOUTHWEST NEBRASKA AND STALL. I HAVE LESS CONFIDENCE FURTHER
SOUTH AND EAST...HOWEVER WITH AT LEAST SOME GUIDANCE SHOWING
DEVELOPMENT TOWARDS THE I-70 CORRIDOR...I FELT COMFORTABLE KEEPING
SLIGHT CHANCE/CHANCE POPS IN PLACE.

BY THURSDAY THIS INITIAL SHORTWAVE WILL MOVE TO THE EAST WITH
SUBSIDENCE BUILDING IN OVER THE CWA IN IT WAKE. AT THE SAME TIME
ANOTHER WEAK DISTURBANCE WILL BE MOVING IN FROM THE WEST BY THURSDAY
AFTERNOON/NIGHT...WITH POPS INCREASING ONCE AGAIN FROM THE
WEST...AND CHANCES LIMITED TO NORTH OF INTERSTATE 70.

FRIDAY-MONDAY...LARGE SCALE TROUGH REMAINS IN PLACE ACROSS THE
WESTERN CONUS...EVENTUALLY BREAKING DOWN AND TRANSITIONING TO A
WESTERLY ZONAL PATTERN BY EARLY NEXT WEEK. RESULT WILL BE A FAIRLY
ACTIVE PATTERN...WITH STORM TRACK FAVORING NORTHERN PORTIONS OF OUR
CWA FOR SHOWER/THUNDERSTORM CHANCES. CONFIDENCE WAS TOO LOW TO RAISE
POPS BEYOND 20/30 RANGE...CONSIDERING DIFFERENCE IN TIMING OF THESE
FEATURES...AND DIFFERENCES IN POSITION OF SURFACE FEATURES AS
HANDLED BY GUIDANCE.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 521 PM MDT MON MAY 21 2012

VFR CONDITIONS ARE FORECAST FOR THE 0Z TAFS. ISOLATED
THUNDERSTORMS WILL CONTINUE TO FORM EAST OF A SURFACE TROUGH OVER
EASTERN COLORADO THROUGH THE EARLY EVENING. MODEL ANALYSIS OF THE
ENVIRONMENT SHOWS THE CONVECTIVE INSTABILITY TAPERING OFF TOWARD KGLD...SO
DO NOT EXPECT THE ISOLATED THUNDERSTORMS TO LAST ONCE THEY MOVE
INTO KANSAS. EXPECT STORMS TO REMAIN NORTH OF KMCK THROUGH THE
EVENING AS THEY TRACK EAST. OTHERWISE THE GUSTY SOUTH WINDS WILL
DECLINE DURING THE EVENING...BUT REMAIN BREEZY THROUGH THE NIGHT.
THERE IS THE POTENTIAL FOR IFR CEILINGS/FOG AT KGLD DURING THE
EARLY MORNING HOURS. HOWEVER MODELS DISAGREE WITH WHETHER THE LOW
LEVELS WILL SATURATE ENOUGH TO DEVELOP A BROKEN CLOUD DECK...SO
WILL LEAVE A SCATTERED DECK FOR NOW AT KGLD. AM NOT TOO CONFIDENT
WITH THE DEVELOPMENT OF FOG EITHER. KGLD SEEMS TO BE ON THE
NORTHERN END OF THE FOG AS IT DEVELOPS MORE TO THE SOUTH. WITH THE
BREEZY WINDS DURING THAT TIME AND THE BRIEF PERIOD OF LOW LEVEL SATURATION
IN THE SOUNDINGS...WILL HOLD OFF UNTIL NEXT TAF ISSUANCE BEFORE
GOING LOWER THAN VFR FOR VIS.


&&

.FIRE WEATHER...
ISSUED AT 121 PM MDT MON MAY 21 2012

VERY WARM AND DRY WEATHER IS EXPECTED ACROSS MUCH OF THE AREA ON
TUESDAY...WITH AFTERNOON HUMIDITIES BELOW 15 PERCENT EXPECTED
ALONG AND EAST OF THE COLORADO AND KANSAS STATE LINE. WESTERLY
WINDS WILL GRADUALLY INCREASE IN THIS AREA TO AROUND 15 MPH IN THE
AFTERNOON. WITH RECENT RAINFALL AND WINDS NOT EXPECTED TO INCREASE
TO LATE IN THE AFTERNOON...OVERALL CONFIDENCE IN CRITICAL FIRE
WEATHER CONDITIONS IS TOO LOW TO WARRANT A WATCH OR WARNING AT
THIS POINT.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&

$$

UPDATE...JTL
SHORT TERM...JRM
LONG TERM...DR
AVIATION...JTL
FIRE WEATHER...JRM







AREA FORECAST DISCUSSION

NWS GOODLAND KS

 532 PM MDT MON MAY 21 2012

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 121 PM MDT MON MAY 21 2012

16Z WATER VAPOR IMAGERY/RUC ANALYSIS INDICATED BROAD RIDGING IN
PLACE ACROSS THE CENTRAL ROCKIES AND ADJACENT HIGH PLAINS...WITH
TROUGH APPROACHING THE PACIFIC NORTHWEST. AT THE SFC...TROUGH WAS IN
PLACE ACROSS CENTRAL AND EASTERN COLORADO ...ROUGHLY BETWEEN KDNR
AND KAKO. TO THE EAST OF THIS TROUGH...MOISTURE ADVECTION WAS
INCREASING WITH AN AREA OF DEW POINTS AT OR ABOVE 50 F FROM KLIC
SOUTHEAST INTO THE OKLAHOMA PANHANDLE. 12Z RAOBS AT DNR AND DDC
INDICATED AREA OF STEEP MID LEVEL LAPSE RATES BETWEEN H7 AND
H6...WITH A MUCH DEEPER LAYER NOTED AT DNR.

MAIN CONCERN FOR THE SHORT TERM PERIODS WILL BE CONVECTIVE
INITIATION CHANCES TODAY AND TEMPS/RH/FIRE WX TOMORROW.

REST OF THE AFTERNOON-TONIGHT...WITH AFOREMENTIONED MOISTURE
ADVECTION ALREADY ONGOING PER SFC OBS...AND NOSE OF STEEP MID LEVEL
LAPSE RATES IN PLACE ALONG SFC TROUGH ACROSS EASTERN COLORADO
CONFIDENCE INCREASING IN CONVECTIVE INITIATION ALONG SFC TROUGH THIS
AFTERNOON...ESPECIALLY GIVEN THAT MIXED LAYER TDS ARE VERY SIMILAR
TO FORECAST SFC VALUES INDICATING SOME DEPTH TO THE MOISTURE
PROFILE. WHILE CONFIDENCE IN DEVELOPMENT OF THUNDERSTORMS IS
HIGHER...HIGHER RES MODELS KEEPING COVERAGE FAIRLY SPARSE AND WITH
LATEST HRRR JUMPING AROUND QUITE A BIT WITH TIMING AND LOCATION...DO
NOT THINK POPS ABOVE THE 20-30 PERCENT RANGE WARRANTED JUST YET.
WITH A LOT OF UNCERTAINTY IN THE DETAILS...HAVE GENERALLY WENT WITH
BROADER COVERAGE OF POPS STARTING FIRST AROUND SFC TROUGH AROUND 20Z
AND GRADUALLY SHIFTING EAST AND DIMINISHING. SOME ELEVATED
INSTABILITY REMAINS THROUGH THE NIGHT WITH SOME WEAK ASCENT EXPECTED
TO THE WEST OF H7 THERMAL RIDGE. PROBABILISTIC GUIDANCE NOT REALLY
SUPPORTING MUCH OF A PRECIP THREAT AT THIS POINT...BUT CANNOT
TOTALLY RULE OUT SOME ELEVATED OVERNIGHT STORMS AND WILL GENERALLY
KEEP PREVIOUS FORECAST IN THIS REGARD. GIVEN ALREADY OBSERVED
MOISTURE TRANSPORT...DO HAVE SOME CONCERNS ABOUT THE DEVELOPMENT OF
FOG OVERNIGHT. WINDS SHOULD GENERALLY STAY UP WHICH WILL MINIMIZE
THE THREAT SOME WHAT...BUT GIVEN EXPECTED MOISTURE PROFILE AND SREF
INDICATING A SMALL THREAT FOR FOG THINK AT LEAST A PATCHY MENTION IS
IN ORDER.

TUESDAY...H5 RIDGE AXIS WILL SHIFT TO THE EAST THROUGH THE
DAY...WITH CWA UNDER THE INFLUENCE OF LARGE SCALE FORCING FOR
SUBSIDENCE THROUGH MUCH OF THE DAY. WHILE SYNOPTIC SCALE SUPPORT IS
LACKING...FAIRLY STRONG AND PERSISTENT CONVERGENCE EXPECTED ALONG
DRY LINE THAT WILL DEVELOP ACROSS AREA DURING THE AFTERNOON. COULD
POTENTIALLY SEE A STORM OR TWO DEVELOP IN THIS AREA...BUT GIVEN
LARGE SCALE PATTERN...POTENTIAL FOR A STRONG CAP AND VERY LOW
PROBABILITIES FROM THE NORMALLY WET SREF DATABASE...CONFIDENCE NOT
HIGH ENOUGH TO INCLUDE THUNDERSTORM THREAT AT THIS TIME. MIXED LAYER
TEMPS STILL SUPPORT TEMPS IN THE 90S ACROSS MUCH OF THE
AREA...ALTHOUGH THERE DOES APPEAR TO BE SOME DISCREPANCIES FOR HOW
WARM THINGS WILL GET WITH SREF INDICATING A RANGE BETWEEN 97 AND
AROUND 88 FOR GLD. GIVEN OVERALL PATTERN AND POTENTIAL TO BE ON MUCH
DRIER SIDE OF THE DRY LINE THINK WARMER SOLUTIONS THE WAY TO AND MADE
ONLY MINOR CHANGES TO GOING FORECAST.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 236 PM MDT MON MAY 21 2012

A COLD FRONT WILL DROP SOUTH TOWARDS OUR CWA TUESDAY NIGHT AS A
SHORTWAVE TROUGH MOVES ACROSS THE NORTHERN PLAINS. WITH AIR MASS OVER
CWA GENERALLY STABILIZING TUESDAY EVENING THUNDERSTORM CHANCES
REMAIN MINIMAL AND WILL BE TIED MAINLY TO WHAT DEVELOPS DURING THE
AFTERNOON. MODEL DIFFERENCES IN THE TIMING/POSITION OF THE FRONT
WILL HAVE A LARGER IMPACT ON THE TEMPERATURE FORECAST WEDNESDAY WHEN
IT WILL STALL OVER THE CWA AND THEN LIFT NORTH AS A WARM FRONT.
ECMWF AND GFS TEND TO BE THE QUICKEST IN DEVELOPING A STRONG LEE
TROUGH OVER EASTERN COLORADO...PUSHING THE FRONT NORTH BY MIDDAY.
CURRENT HIGH TEMP FORECAST FOR WEDNESDAY REFLECTS A BLEND OF
SOLUTIONS WITH UPPER 90S OVER SW PART OF THE CWA...AND UPPER 70S IN
THE NORTHWEST. WERE THE FRONT TO LIFT QUICKER...MID-UPPER 90S COULD
BE EXPECTED ACROSS A MUCH LARGER PART OF THE CWA. WITH THE SURFACE
TROUGH EXPECTED TO BE OVER THE CWA BY MIDDAY...STRONGEST SURFACE
GRADIENT SHOULD REMAIN EAST...SO WINDS SHOULD REMAIN BELOW RED FLAG
CRITERIA.

LARGE SCALE TROUGH DEVELOPS OVER THE GREAT BASIN/NORTHERN ROCKIES BY
WEDNESDAY AFTERNOON...WITH A SERIES OF WEAK SHORTWAVE TROUGH MOVING
JUST NORTH AND WEST OF THE CWA THROUGH NEXT WEEKEND. THE FIRST
SHORTWAVE ARRIVES BY WEDNESDAY NIGHT...WITH THUNDERSTORMS POSSIBLY
INITIATING OVER NORTHEAST COLORADO. BEST CHANCES WILL BE ACROSS THE
NORTH AFTER MIDNIGHT WEDNESDAY NIGHT WHEN A COLD FRONT WILL MOVE
INTO SOUTHWEST NEBRASKA AND STALL. I HAVE LESS CONFIDENCE FURTHER
SOUTH AND EAST...HOWEVER WITH AT LEAST SOME GUIDANCE SHOWING
DEVELOPMENT TOWARDS THE I-70 CORRIDOR...I FELT COMFORTABLE KEEPING
SLIGHT CHANCE/CHANCE POPS IN PLACE.

BY THURSDAY THIS INITIAL SHORTWAVE WILL MOVE TO THE EAST WITH
SUBSIDENCE BUILDING IN OVER THE CWA IN IT WAKE. AT THE SAME TIME
ANOTHER WEAK DISTURBANCE WILL BE MOVING IN FROM THE WEST BY THURSDAY
AFTERNOON/NIGHT...WITH POPS INCREASING ONCE AGAIN FROM THE
WEST...AND CHANCES LIMITED TO NORTH OF INTERSTATE 70.

FRIDAY-MONDAY...LARGE SCALE TROUGH REMAINS IN PLACE ACROSS THE
WESTERN CONUS...EVENTUALLY BREAKING DOWN AND TRANSITIONING TO A
WESTERLY ZONAL PATTERN BY EARLY NEXT WEEK. RESULT WILL BE A FAIRLY
ACTIVE PATTERN...WITH STORM TRACK FAVORING NORTHERN PORTIONS OF OUR
CWA FOR SHOWER/THUNDERSTORM CHANCES. CONFIDENCE WAS TOO LOW TO RAISE
POPS BEYOND 20/30 RANGE...CONSIDERING DIFFERENCE IN TIMING OF THESE
FEATURES...AND DIFFERENCES IN POSITION OF SURFACE FEATURES AS
HANDLED BY GUIDANCE.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 521 PM MDT MON MAY 21 2012

VFR CONDITIONS ARE FORECAST FOR THE 0Z TAFS. ISOLATED
THUNDERSTORMS WILL CONTINUE TO FORM EAST OF A SURFACE TROUGH OVER
EASTERN COLORADO THROUGH THE EARLY EVENING. MODEL ANALYSIS OF THE
ENVIRONMENT SHOWS THE CONVECTIVE INSTABILITY TAPERING OFF TOWARD KGLD...SO
DO NOT EXPECT THE ISOLATED THUNDERSTORMS TO LAST ONCE THEY MOVE
INTO KANSAS. EXPECT STORMS TO REMAIN NORTH OF KMCK THROUGH THE
EVENING AS THEY TRACK EAST. OTHERWISE THE GUSTY SOUTH WINDS WILL
DECLINE DURING THE EVENING...BUT REMAIN BREEZY THROUGH THE NIGHT.
THERE IS THE POTENTIAL FOR IFR CEILINGS/FOG AT KGLD DURING THE
EARLY MORNING HOURS. HOWEVER MODELS DISAGREE WITH WHETHER THE LOW
LEVELS WILL SATURATE ENOUGH TO DEVELOP A BROKEN CLOUD DECK...SO
WILL LEAVE A SCATTERED DECK FOR NOW AT KGLD. AM NOT TOO CONFIDENT
WITH THE DEVELOPMENT OF FOG EITHER. KGLD SEEMS TO BE ON THE
NORTHERN END OF THE FOG AS IT DEVELOPS MORE TO THE SOUTH. WITH THE
BREEZY WINDS DURING THAT TIME AND THE BRIEF PERIOD OF LOW LEVEL SATURATION
IN THE SOUNDINGS...WILL HOLD OFF UNTIL NEXT TAF ISSUANCE BEFORE
GOING LOWER THAN VFR FOR VIS.

&&

.FIRE WEATHER...
ISSUED AT 121 PM MDT MON MAY 21 2012

VERY WARM AND DRY WEATHER IS EXPECTED ACROSS MUCH OF THE AREA ON
TUESDAY...WITH AFTERNOON HUMIDITIES BELOW 15 PERCENT EXPECTED
ALONG AND EAST OF THE COLORADO AND KANSAS STATE LINE. WESTERLY
WINDS WILL GRADUALLY INCREASE IN THIS AREA TO AROUND 15 MPH IN THE
AFTERNOON. WITH RECENT RAINFALL AND WINDS NOT EXPECTED TO INCREASE
TO LATE IN THE AFTERNOON...OVERALL CONFIDENCE IN CRITICAL FIRE
WEATHER CONDITIONS IS TOO LOW TO WARRANT A WATCH OR WARNING AT
THIS POINT.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&

$$

SHORT TERM...JRM
LONG TERM...DR
AVIATION...JTL
FIRE WEATHER...JRM







AREA FORECAST DISCUSSION

NWS DODGE CITY KS

 308 PM CDT SUN MAY 20 2012

...UPDATED LONG TERM SECTION...

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 335 AM CDT SUN MAY 20 2012

THE LATEST NAM AND RUC MODEL GUIDANCE SHOWS THE BAND OF 700 MILLIBAR
FRONTOGENETIC FORCING ACROSS FAR WESTERN KANSAS EARLY THIS MORNING.
THE MODELS MOVE THIS AREA OF FORCING EASTWARD AND WEAKEN IT
THROUGH SUNRISE. GIVEN THE GOING RADAR TRENDS, EXPECT THE
PRECIPITATION TO BE MOVING OUT OF WESTERN KANSAS AND THROUGH
CENTRAL KANSAS BY 12Z AS THE FORCING MOVES EAST AND WEAKENS.

WINDS HAVE BECOME LIGHT AND VARIABLE AS THE BOUNDARY LAYER
DECOUPLED THIS EVENING. SURFACE HIGH PRESSURE WILL BE BUILDING
INTO WESTERN KANSAS THROUGH THIS MORNING. WE SHOULD SEE A PERIOD
OF WINDS GUSTING TO AROUND 20 KNOTS OR SO DEVELOPING AFTER
SUNRISE. WINDS WILL DIMINISH AND SWITCH TO THE EAST/NORTHEAST THIS
AFTERNOON AS THE HIGH PRESSURE MOVES OFF TO THE EAST.

WIDELY SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP OFF THE FRONT
RANGE OF THE ROCKIES THIS AFTERNOON AS SOME LIMITED INSTABILITY
DEVELOPS WITH CAPE VALUES AROUND 500 J/KG OR SO. MODEL SOUNDINGS
ACROSS FAR SOUTHWEST KANSAS ARE MORE STABLE SO EXPECT THAT ANY
THUNDERSTORMS THAT DEVELOP WILL PROBABLY STAY IN EASTERN COLORADO
BEFORE DIMINISHING WITH SUNSET.

SKIES SHOULD BE MOSTLY CLEAR TONIGHT AS UPPER LEVEL RIDGING CONTINUES
TO DEVELOP. LOW TEMPERATURES MAY FALL INTO THE UPPER 40S AROUND HAYS
AND LARNED CLOSER TO THE SURFACE HIGH PRESSURE. FARTHER WEST...LOWS
SHOULD STAY IN THE MID 50S AROUND ELKHART WHERE WINDS WILL STAY UP
A LITTLE MORE TONIGHT.

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 306 PM CDT SUN MAY 20 2012

MONDAY NIGHT THROUGH WEDNESDAY:
MID-UPPER TROPOSPHERIC RIDGING WILL MOVE QUICKLY EAST FROM THE
ROCKIES MONDAY NIGHT TO THE EASTERN CONUS BY WEDNESDAY.  IN ITS
WAKE...A STRONG PACIFIC JET WILL NOSE INTO THE INTERMOUNTAIN
WEST/CENTRAL ROCKIES BY WEDNESDAY.  WHAT THIS WILL RESULT IN IS A
CONTINUED SLOW DEEPENING OF THE LEE TROUGH ACROSS EASTERN
COLORADO...WITH LOW DEVELOPMENT ALONG THE LEE TROUGH WEDNESDAY AHEAD
OF AN APPROACHING COLD FRONT.  ON MONDAY NIGHT WILL HAVE SOME 15 TO
20 POPS GOING FROM ELKHART TO SYRACUSE FOR ANY COLORADO STORMS
(PARTICULARLY OFF THE PALMER DIVIDE) WHICH MAY FORM AND DRIFT
SOUTHEAST TOWARD THE STATE BORDER.  THE LATEST NAM12 DOES SUPPORT
CONVECTION APPROACHING THE STATE BORDER DURING THE MID TO LATE
EVENING HOURS BEFORE DISSIPATING DUE TO LACK OF LARGE SCALE ASCENT.
FROM 09-15Z TUESDAY...WILL HAVE TO WATCH FOR THE DEVELOPMENT OF SOME
ELEVATED CONVECTION ON THE NOSE OF A RETURNING MOISTURE PLUME.

THE GFS MODEL IS THE ONLY MODEL WHICH SHOWS A SOMEWHAT COHERENT
CONVECTIVE QPF SIGNAL WHEREAS THE ECMWF AND NAM ARE MORE OR LESS
DRY.  A LOOK AT THE 09Z RUN OF THE SREF ALSO SUPPORTS THE DRIER
SOLUTION SO WILL KEEP POPS OUT OF THE GRIDS FOR 09-18Z TUESDAY.  AN
ISOLATED THUNDERSTORM OR TWO MAY FORM NEAR THE SPRINGFIELD LOW LATE
TUESDAY AFTERNOON AS TEMPERATURES WARM TO THE LOWER-MID 90S SO WILL
INCLUDE SOME 15-20 POPS FOR MAINLY THE MORTON COUNTY AREA LATE TUES
AFTERNOON INTO THE EVENING HOURS.  HAVE BUMPED UP THE WIND SPEEDS
TUESDAY (TO 22-25 KNOTS SUSTAINED DURING THE AFTERNOON) AS THE LEE
TROUGH PRESSURE GRADIENT WILL BE QUITE STRONG IN ADVANCE OF THE
ROCKIES UPPER JET STREAK.  13 TO 18 KNOTS OF SOUTH TO SOUTHWEST WIND
SHOULD LAST THROUGH MUCH OF THE NIGHT TUESDAY NIGHT KEEPING
TEMPERATURES RATHER MILD WITH LOWS IN THE LOWER TO MID 60S.

WEDNESDAY FORECAST IS DIFFICULT DEPENDING ON THE STRENGTH OF THE
FRONT.  IF THE FRONT IS SLOWER PER THE 00Z RUN OF THE ECMWF...THEN
VERY HOT CONDITIONS WILL DEVELOP ACROSS SOUTHWEST KANSAS WEDNESDAY
AFTERNOON WITH WIDESPREAD 100 DEGREE HEAT.  THE 12Z RUNS OF THE GFS
AND ESPECIALLY THE NAM SUPPORT A MORE AGGRESSIVE PUSH OF THE COLD
FRONT AND KEEPING TEMPERATURES QUITE A BIT COOLER.  THE OFFICIAL
FORECAST WILL CONTINUE TO REFLECT LOWER 90S FOR MOST AREAS...BUT
THIS IS SUBJECT TO CHANGE IN FUTURE UPDATES.

THURSDAY THROUGH SUNDAY:
THE FIRST JET STREAK THAT APPROACHES THE ROCKIES WEDNESDAY/WEDNESDAY
NIGHT WILL EJECT NORTHEAST INTO THE NORTHERN PLAINS.  THE FRONT THAT
PUSHES SOUTH DUE TO THIS JET WILL EVENTUALLY STALL OUT WEDNESDAY
NIGHT/THURSDAY SOMEWHERE OVER OR NEAR SOUTHWEST KANSAS.  THE NEXT
DEEP TROUGH WILL DEVELOP OVER CALIFORNIA/GREAT BASIN REGION LATE
THURSDAY INTO FRIDAY.  THE FRONT SHOULD LIFT BACK NORTH AS A WARM
FRONT...ESPECIALLY IF THE ECMWF IS BELIEVED.  THE DETERMINISTIC GFS
AND ECMWF SOLUTIONS DO NOT AGREE ON THE DOWNSTREAM JET CONFIGURATION
AND THE STRENGTH OF THE UPPER HIGH TO ITS SOUTH.  THE ECMWF MODEL
WOULD YIELD MUCH MORE SUMMER-LIKE WEATHER WITH HOT TEMPERATURES IN
THE MID TO UPPER 90S EACH DAY AND PRETTY MUCH NO PRECIPITATION WITH
THE FRONT WELL TO THE NORTH.  THE GFS ON THE OTHER HAND HAS A MORE
ROBUST SURFACE HIGH TO THE NORTH KEEPING THE FRONT ACROSS THE
CENTRAL PLAINS AND YIELDING QUITE A BIT OF PRECIPITATION FOR WESTERN
KANSAS.  THE TEMPTATION IS TO GO WITH THE ECMWF GIVEN ITS BETTER
LONG-TERM SKILL AT THESE FORECAST HOURS OVER THE GFS.  AS SUCH...ALL
POPS ARE KEPT BELOW 15 PERCENT FOR NOW.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1256 PM CDT SUN MAY 20 2012

SURFACE HIGH PRESSURE WILL SETTLE ACROSS WESTERN KANSAS THIS AFTERNOON
AND TONIGHT, RESULTING IN DECREASING WINDS AND A CHANGE IN DIRECTION
FROM NORTHEAST TO SOUTHEAST. WINDS WILL BEGIN TO INCREASE BY
13-15Z MONDAY AS A TROUGH OF LOW PRESSURE DEVELOPS IN THE LEE OF
THE ROCKIES.


&&

.PRELIMINARY POINT TEMPS/POPS...
DDC  48  82  58  92 /   0  10  10  10
GCK  49  82  58  95 /  10  10  10  10
EHA  54  82  58  95 /  10  20  20  20
LBL  53  82  59  94 /  10  20  20  10
HYS  48  81  58  91 /   0  10  10  10
P28  53  81  59  87 /   0  10  10  10

&&

.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...GERARD
LONG TERM...UMSCHEID
AVIATION...FINCH







AREA FORECAST DISCUSSION

NWS DODGE CITY KS

 1259 PM CDT SUN MAY 20 2012

...UPATED FOR AVIATION DISCUSSION...

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 335 AM CDT SUN MAY 20 2012

THE LATEST NAM AND RUC MODEL GUIDANCE SHOWS THE BAND OF 700 MILLIBAR
FRONTOGENETIC FORCING ACROSS FAR WESTERN KANSAS EARLY THIS MORNING.
THE MODELS MOVE THIS AREA OF FORCING EASTWARD AND WEAKEN IT
THROUGH SUNRISE. GIVEN THE GOING RADAR TRENDS, EXPECT THE
PRECIPITATION TO BE MOVING OUT OF WESTERN KANSAS AND THROUGH
CENTRAL KANSAS BY 12Z AS THE FORCING MOVES EAST AND WEAKENS.

WINDS HAVE BECOME LIGHT AND VARIABLE AS THE BOUNDARY LAYER
DECOUPLED THIS EVENING. SURFACE HIGH PRESSURE WILL BE BUILDING
INTO WESTERN KANSAS THROUGH THIS MORNING. WE SHOULD SEE A PERIOD
OF WINDS GUSTING TO AROUND 20 KNOTS OR SO DEVELOPING AFTER
SUNRISE. WINDS WILL DIMINISH AND SWITCH TO THE EAST/NORTHEAST THIS
AFTERNOON AS THE HIGH PRESSURE MOVES OFF TO THE EAST.

WIDELY SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP OFF THE FRONT
RANGE OF THE ROCKIES THIS AFTERNOON AS SOME LIMITED INSTABILITY
DEVELOPS WITH CAPE VALUES AROUND 500 J/KG OR SO. MODEL SOUNDINGS
ACROSS FAR SOUTHWEST KANSAS ARE MORE STABLE SO EXPECT THAT ANY
THUNDERSTORMS THAT DEVELOP WILL PROBABLY STAY IN EASTERN COLORADO
BEFORE DIMINISHING WITH SUNSET.

SKIES SHOULD BE MOSTLY CLEAR TONIGHT AS UPPER LEVEL RIDGING CONTINUES
TO DEVELOP. LOW TEMPERATURES MAY FALL INTO THE UPPER 40S AROUND HAYS
AND LARNED CLOSER TO THE SURFACE HIGH PRESSURE. FARTHER WEST...LOWS
SHOULD STAY IN THE MID 50S AROUND ELKHART WHERE WINDS WILL STAY UP
A LITTLE MORE TONIGHT.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 335 AM CDT SUN MAY 20 2012

SHORT RANGE MODELS INDICATE A WEAK UPPER LEVEL RIDGE OF HIGH
PRESSURE DEVELOPING ACROSS THE ROCKIES EARLY MONDAY SETTING UP A
NORTHWESTERLY FLOW ALOFT ACROSS THE WESTERN HIGH PLAINS. MEANWHILE,
SURFACE HIGH PRESSURE WILL BE TRACKING EAST OUT OF THE NORTHERN
PLAINS INTO THE UPPER MIDWEST HELPING TO INFLUENCE A SOUTHEASTERLY
UPSLOPE FLOW ACROSS THE WESTERN HIGH PLAINS. AS A RESULT, DIURNALLY
DRIVEN ISOLATED TO WIDELY SCATTERED THUNDERSTORMS ARE EXPECTED TO
DEVELOP JUST LEE OF THE ROCKIES MONDAY AFTERNOON AND EVENING,
POTENTIALLY DRIFTING EASTWARD INTO FAR SOUTHWESTERN KANSAS. WILL
RETAIN THE SLIGHT POPS ACROSS OUR FAR SOUTHWEST DUE TO THE EXPECTED
WEAK FLOW ALOFT COMBINED WITH THE UNCERTAINTY AS TO HOW FAR EAST
ANY DEVELOPING STORMS MAY REACH BEFORE DISSIPATING.

MEDIUM RANGE MODELS SHOW AN UPPER LEVEL TROUGH TRACKING SOUTHEAST
ACROSS THE PACIFIC NORTHWEST INTO THE ROCKY MOUNTAIN REGION TUESDAY
SETTING UP FOR ANOTHER CHANCE FOR PRECIP TO PORTIONS OF CENTRAL AND
WESTERN KANSAS. AS THE SYSTEM APPROACHES, INCREASING FIELDS OF
DIVERGENCE ALOFT WILL DEVELOP DOWNSTREAM OF THE TROUGH AXIS.
ADDITIONALLY, A PREVAILING LOW LEVEL SOUTHEASTERLY UPSLOPE FLOW
ACROSS THE WESTERN HIGH PLAINS WILL HELP WITH INCREASED FORCING AS
WELL AS ADVECT MORE MOISTURE NORTHWARD INTO THE REGION. AS A RESULT,
THE CHANCE FOR A FEW SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS
PORTIONS OF CENTRAL AND WESTERN KANSAS INTO TUESDAY. DRIER
CONDITIONS ARE EXPECTED ACROSS WESTERN KANSAS WEDNESDAY AS A
DEVELOPING SURFACE LOW LEE OF THE ROCKIES STRENGTHENS HELPING TO
DRAW DRIER AIR NORTHEASTWARD INTO SOUTHWEST KANSAS.

TEMPERATURES WILL BE SLIGHTLY WARMER GOING INTO MONDAY AS SURFACE
HIGH PRESSURE DROPS SOUTHEAST OUT OF THE NORTHERN PLAINS INTO THE
MID MISSISSIPPI RIVER VALLEY. THIS WILL HELP KEEP A SOUTHEASTERLY
LOW LEVEL FLOW IN PLACE ACROSS WESTERN KANSAS ALLOWING FOR SOME
MODEST WARM AIR ADVECTION. THE NAM, GFS, AND ECMWF SHOW H85
TEMPERATURES RANGING FROM THE MID TEENS(C) ACROSS CENTRAL KANSAS
TO NEAR 20C ALONG THE COLORADO BORDER. LOOK FOR HIGHS TO BE NEAR
TO JUST ABOVE 80F MONDAY AFTERNOON WITH A FEW UPPER 70S(F) STILL
POSSIBLE IN SOME LOCATIONS...MAINLY IN CENTRAL KANSAS. THE WARMING
TREND WILL CONTINUE INTO TUESDAY AS LEE SIDE TROUGHING STRENGTHENS
ACROSS EASTERN COLORADO. ENHANCED WARM AIR ADVECTION WITHIN A
STRONGER SOUTH TO SOUTHWESTERLY FLOW WILL RAISE H85 TEMPERATURES
UP TO NEAR 20C ACROSS CENTRAL KANSAS TO THE UPPER 20S(C) ACROSS
FAR SOUTHWEST KANSAS. EXPECT HIGHS FROM THE MID TO UPPER 80S(F) IN
CENTRAL KANSAS TUESDAY AFTERNOON TO THE LOWER TO MID 90S(F) IN
EXTREME SOUTHWEST KANSAS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1256 PM CDT SUN MAY 20 2012

SURFACE HIGH PRESSURE WILL SETTLE ACROSS WESTERN KANSAS THIS AFTERNOON
AND TONIGHT, RESULTING IN DECREASING WINDS AND A CHANGE IN DIRECTION
FROM NORTHEAST TO SOUTHEAST. WINDS WILL BEGIN TO INCREASE BY
13-15Z MONDAY AS A TROUGH OF LOW PRESSURE DEVELOPS IN THE LEE OF
THE ROCKIES.

&&

.PRELIMINARY POINT TEMPS/POPS...
DDC  77  52  81  60 /  50   0  10  10
GCK  77  51  81  60 /  40  10  10  10
EHA  77  55  82  60 /   0  10  20  20
LBL  78  56  82  61 /   0  10  20  20
HYS  77  48  81  60 /   0   0  10  10
P28  78  55  80  61 /  10  10  10  10

&&

.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...GERARD
LONG TERM...JJOHNSON
AVIATION...FINCH







AREA FORECAST DISCUSSION

NWS DODGE CITY KS

 525 AM CDT SUN MAY 20 2012

...UPDATE FOR THE SHORT TERM FORECAST...

.UPDATE...
ISSUED AT 519 AM CDT SUN MAY 20 2012

UPDATED THE FORECAST TO INCLUDE THUNDER WITH THE ONGOING SMALL
AREA OF SHOWERS OVER PARTS OF WEST CENTRAL AND SOUTHWEST KANSAS
EARLY THIS MORNING. REFLECTIVITY IN THE CELLS HAS INCREASED A BIT
OVER THE PAST HOUR AND LIGHTNING DETECTION NETWORK HAS BEEN
INDICATING A FEW STRIKES. EXTRAPOLATION OF THE VORT MAX IN THE
WATER VAPOR IMAGERY SHOWS THE AREA OF PRECIPITATION MOVING INTO
CENTRAL KANSAS AROUND 13-15Z SO WILL HANG ON TO SOME SMALL POPS
AROUND LARNED AND LACROSSE THROUGH THAT TIME.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 335 AM CDT SUN MAY 20 2012

THE LATEST NAM AND RUC MODEL GUIDANCE SHOWS THE BAND OF 700 MILLIBAR
FRONTOGENETIC FORCING ACROSS FAR WESTERN KANSAS EARLY THIS MORNING.
THE MODELS MOVE THIS AREA OF FORCING EASTWARD AND WEAKEN IT
THROUGH SUNRISE. GIVEN THE GOING RADAR TRENDS, EXPECT THE
PRECIPITATION TO BE MOVING OUT OF WESTERN KANSAS AND THROUGH
CENTRAL KANSAS BY 12Z AS THE FORCING MOVES EAST AND WEAKENS.

WINDS HAVE BECOME LIGHT AND VARIABLE AS THE BOUNDARY LAYER
DECOUPLED THIS EVENING. SURFACE HIGH PRESSURE WILL BE BUILDING
INTO WESTERN KANSAS THROUGH THIS MORNING. WE SHOULD SEE A PERIOD
OF WINDS GUSTING TO AROUND 20 KNOTS OR SO DEVELOPING AFTER
SUNRISE. WINDS WILL DIMINISH AND SWITCH TO THE EAST/NORTHEAST THIS
AFTERNOON AS THE HIGH PRESSURE MOVES OFF TO THE EAST.

WIDELY SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP OFF THE FRONT
RANGE OF THE ROCKIES THIS AFTERNOON AS SOME LIMITED INSTABILITY
DEVELOPS WITH CAPE VALUES AROUND 500 J/KG OR SO. MODEL SOUNDINGS
ACROSS FAR SOUTHWEST KANSAS ARE MORE STABLE SO EXPECT THAT ANY
THUNDERSTORMS THAT DEVELOP WILL PROBABLY STAY IN EASTERN COLORADO
BEFORE DIMINISHING WITH SUNSET.

SKIES SHOULD BE MOSTLY CLEAR TONIGHT AS UPPER LEVEL RIDGING CONTINUES
TO DEVELOP. LOW TEMPERATURES MAY FALL INTO THE UPPER 40S AROUND HAYS
AND LARNED CLOSER TO THE SURFACE HIGH PRESSURE. FARTHER WEST...LOWS
SHOULD STAY IN THE MID 50S AROUND ELKHART WHERE WINDS WILL STAY UP
A LITTLE MORE TONIGHT.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 335 AM CDT SUN MAY 20 2012

SHORT RANGE MODELS INDICATE A WEAK UPPER LEVEL RIDGE OF HIGH
PRESSURE DEVELOPING ACROSS THE ROCKIES EARLY MONDAY SETTING UP A
NORTHWESTERLY FLOW ALOFT ACROSS THE WESTERN HIGH PLAINS. MEANWHILE,
SURFACE HIGH PRESSURE WILL BE TRACKING EAST OUT OF THE NORTHERN
PLAINS INTO THE UPPER MIDWEST HELPING TO INFLUENCE A SOUTHEASTERLY
UPSLOPE FLOW ACROSS THE WESTERN HIGH PLAINS. AS A RESULT, DIURNALLY
DRIVEN ISOLATED TO WIDELY SCATTERED THUNDERSTORMS ARE EXPECTED TO
DEVELOP JUST LEE OF THE ROCKIES MONDAY AFTERNOON AND EVENING,
POTENTIALLY DRIFTING EASTWARD INTO FAR SOUTHWESTERN KANSAS. WILL
RETAIN THE SLIGHT POPS ACROSS OUR FAR SOUTHWEST DUE TO THE EXPECTED
WEAK FLOW ALOFT COMBINED WITH THE UNCERTAINTY AS TO HOW FAR EAST
ANY DEVELOPING STORMS MAY REACH BEFORE DISSIPATING.

MEDIUM RANGE MODELS SHOW AN UPPER LEVEL TROUGH TRACKING SOUTHEAST
ACROSS THE PACIFIC NORTHWEST INTO THE ROCKY MOUNTAIN REGION TUESDAY
SETTING UP FOR ANOTHER CHANCE FOR PRECIP TO PORTIONS OF CENTRAL AND
WESTERN KANSAS. AS THE SYSTEM APPROACHES, INCREASING FIELDS OF
DIVERGENCE ALOFT WILL DEVELOP DOWNSTREAM OF THE TROUGH AXIS.
ADDITIONALLY, A PREVAILING LOW LEVEL SOUTHEASTERLY UPSLOPE FLOW
ACROSS THE WESTERN HIGH PLAINS WILL HELP WITH INCREASED FORCING AS
WELL AS ADVECT MORE MOISTURE NORTHWARD INTO THE REGION. AS A RESULT,
THE CHANCE FOR A FEW SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS
PORTIONS OF CENTRAL AND WESTERN KANSAS INTO TUESDAY. DRIER
CONDITIONS ARE EXPECTED ACROSS WESTERN KANSAS WEDNESDAY AS A
DEVELOPING SURFACE LOW LEE OF THE ROCKIES STRENGTHENS HELPING TO
DRAW DRIER AIR NORTHEASTWARD INTO SOUTHWEST KANSAS.

TEMPERATURES WILL BE SLIGHTLY WARMER GOING INTO MONDAY AS SURFACE
HIGH PRESSURE DROPS SOUTHEAST OUT OF THE NORTHERN PLAINS INTO THE
MID MISSISSIPPI RIVER VALLEY. THIS WILL HELP KEEP A SOUTHEASTERLY
LOW LEVEL FLOW IN PLACE ACROSS WESTERN KANSAS ALLOWING FOR SOME
MODEST WARM AIR ADVECTION. THE NAM, GFS, AND ECMWF SHOW H85
TEMPERATURES RANGING FROM THE MID TEENS(C) ACROSS CENTRAL KANSAS
TO NEAR 20C ALONG THE COLORADO BORDER. LOOK FOR HIGHS TO BE NEAR
TO JUST ABOVE 80F MONDAY AFTERNOON WITH A FEW UPPER 70S(F) STILL
POSSIBLE IN SOME LOCATIONS...MAINLY IN CENTRAL KANSAS. THE WARMING
TREND WILL CONTINUE INTO TUESDAY AS LEE SIDE TROUGHING STRENGTHENS
ACROSS EASTERN COLORADO. ENHANCED WARM AIR ADVECTION WITHIN A
STRONGER SOUTH TO SOUTHWESTERLY FLOW WILL RAISE H85 TEMPERATURES
UP TO NEAR 20C ACROSS CENTRAL KANSAS TO THE UPPER 20S(C) ACROSS
FAR SOUTHWEST KANSAS. EXPECT HIGHS FROM THE MID TO UPPER 80S(F) IN
CENTRAL KANSAS TUESDAY AFTERNOON TO THE LOWER TO MID 90S(F) IN
EXTREME SOUTHWEST KANSAS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1257 AM CDT SUN MAY 20 2012

WILL SHOW SOME SCATTERED TO BROKEN MID/UPPER LEVEL CLOUDINESS ACROSS
CENTRAL AND SOUTHWEST KANSAS THROUGH THE EARLY MORNING HOURS AS A WEAK
DISTURBANCE MOVES OVER THE AREA. AN ASSOCIATED SMALL AREA OF LIGHT RAIN
SHOWERS OR SPRINKLES WILL ALSO MOVE THROUGH THE AREA. THIS PRECIPITATION
IS VERY LIGHT SO VISIBILITIES SHOULD REMAIN IN THE VFR CATEGORY. NORTHERLY
WINDS MAY BECOME GUSTY FOR A TIME AFTER SUNRISE BUT SHOULD DECREASE
AGAIN AND SWITCH AROUND TO THE NORTHEAST AFTER 18Z.


&&

.PRELIMINARY POINT TEMPS/POPS...
DDC  77  52  81  60 /   0   0  10  10
GCK  77  51  81  60 /  10  10  10  10
EHA  77  55  82  60 /   0  10  20  20
LBL  78  56  82  61 /   0  10  20  20
HYS  77  48  81  60 /  10   0  10  10
P28  78  55  80  61 /  20  10  10  10

&&

.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...GERARD
SYNOPSIS...GERARD
SHORT TERM...GERARD
LONG TERM...JJOHNSON
AVIATION...GERARD







AREA FORECAST DISCUSSION

NWS DODGE CITY KS

 335 AM CDT SUN MAY 20 2012

...UPDATED SYNOPSIS...SHORT TERM AND LONG TERM DISCUSSIONS...

.SYNOPSIS...
ISSUED AT 335 AM CDT SUN MAY 20 2012

WATER VAPOR LOOPS SHOW A WEAK VORT MAX TRAILING THE MAIN SHORTWAVE
TROUGH THAT MOVED OUT OVER THE CENTRAL HIGH PLAINS SUNDAY
AFTERNOON. A SMALL AREA OF LIGHT RAIN SHOWERS WAS MOVING INTO FAR
WEST CENTRAL KANSAS...APPARENTLY BEING FORCED ALONG A BAND OF MID
LEVEL FRONTOGENETIC FORCING. FARTHER WEST...AN UPPER LEVEL RIDGE WAS
BUILDING OVER THE ROCKIES AS EVIDENT IN THE WIDESPREAD 50-70 METER
HEIGHT RISES AT 500 MILLIBARS FROM WASHINGTON STATE TO COLORADO
AND NEW MEXICO. SURFACE HIGH PRESSURE CONTINUED TO NOSE SOUTHWARD
INTO THE CENTRAL HIGH PLAINS.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 335 AM CDT SUN MAY 20 2012

THE LATEST NAM AND RUC MODEL GUIDANCE SHOWS THE BAND OF 700 MILLIBAR
FRONTOGENETIC FORCING ACROSS FAR WESTERN KANSAS EARLY THIS MORNING.
THE MODELS MOVE THIS AREA OF FORCING EASTWARD AND WEAKEN IT
THROUGH SUNRISE. GIVEN THE GOING RADAR TRENDS, EXPECT THE
PRECIPITATION TO BE MOVING OUT OF WESTERN KANSAS AND THROUGH
CENTRAL KANSAS BY 12Z AS THE FORCING MOVES EAST AND WEAKENS.

WINDS HAVE BECOME LIGHT AND VARIABLE AS THE BOUNDARY LAYER
DECOUPLED THIS EVENING. SURFACE HIGH PRESSURE WILL BE BUILDING
INTO WESTERN KANSAS THROUGH THIS MORNING. WE SHOULD SEE A PERIOD
OF WINDS GUSTING TO AROUND 20 KNOTS OR SO DEVELOPING AFTER
SUNRISE. WINDS WILL DIMINISH AND SWITCH TO THE EAST/NORTHEAST THIS
AFTERNOON AS THE HIGH PRESSURE MOVES OFF TO THE EAST.

WIDELY SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP OFF THE FRONT
RANGE OF THE ROCKIES THIS AFTERNOON AS SOME LIMITED INSTABILITY
DEVELOPS WITH CAPE VALUES AROUND 500 J/KG OR SO. MODEL SOUNDINGS
ACROSS FAR SOUTHWEST KANSAS ARE MORE STABLE SO EXPECT THAT ANY
THUNDERSTORMS THAT DEVELOP WILL PROBABLY STAY IN EASTERN COLORADO
BEFORE DIMINISHING WITH SUNSET.

SKIES SHOULD BE MOSTLY CLEAR TONIGHT AS UPPER LEVEL RIDGING CONTINUES
TO DEVELOP. LOW TEMPERATURES MAY FALL INTO THE UPPER 40S AROUND HAYS
AND LARNED CLOSER TO THE SURFACE HIGH PRESSURE. FARTHER WEST...LOWS
SHOULD STAY IN THE MID 50S AROUND ELKHART WHERE WINDS WILL STAY UP
A LITTLE MORE TONIGHT.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 335 AM CDT SUN MAY 20 2012

SHORT RANGE MODELS INDICATE A WEAK UPPER LEVEL RIDGE OF HIGH
PRESSURE DEVELOPING ACROSS THE ROCKIES EARLY MONDAY SETTING UP A
NORTHWESTERLY FLOW ALOFT ACROSS THE WESTERN HIGH PLAINS. MEANWHILE,
SURFACE HIGH PRESSURE WILL BE TRACKING EAST OUT OF THE NORTHERN
PLAINS INTO THE UPPER MIDWEST HELPING TO INFLUENCE A SOUTHEASTERLY
UPSLOPE FLOW ACROSS THE WESTERN HIGH PLAINS. AS A RESULT, DIURNALLY
DRIVEN ISOLATED TO WIDELY SCATTERED THUNDERSTORMS ARE EXPECTED TO
DEVELOP JUST LEE OF THE ROCKIES MONDAY AFTERNOON AND EVENING,
POTENTIALLY DRIFTING EASTWARD INTO FAR SOUTHWESTERN KANSAS. WILL
RETAIN THE SLIGHT POPS ACROSS OUR FAR SOUTHWEST DUE TO THE EXPECTED
WEAK FLOW ALOFT COMBINED WITH THE UNCERTAINTY AS TO HOW FAR EAST
ANY DEVELOPING STORMS MAY REACH BEFORE DISSIPATING.

MEDIUM RANGE MODELS SHOW AN UPPER LEVEL TROUGH TRACKING SOUTHEAST
ACROSS THE PACIFIC NORTHWEST INTO THE ROCKY MOUNTAIN REGION TUESDAY
SETTING UP FOR ANOTHER CHANCE FOR PRECIP TO PORTIONS OF CENTRAL AND
WESTERN KANSAS. AS THE SYSTEM APPROACHES, INCREASING FIELDS OF
DIVERGENCE ALOFT WILL DEVELOP DOWNSTREAM OF THE TROUGH AXIS.
ADDITIONALLY, A PREVAILING LOW LEVEL SOUTHEASTERLY UPSLOPE FLOW
ACROSS THE WESTERN HIGH PLAINS WILL HELP WITH INCREASED FORCING AS
WELL AS ADVECT MORE MOISTURE NORTHWARD INTO THE REGION. AS A RESULT,
THE CHANCE FOR A FEW SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS
PORTIONS OF CENTRAL AND WESTERN KANSAS INTO TUESDAY. DRIER
CONDITIONS ARE EXPECTED ACROSS WESTERN KANSAS WEDNESDAY AS A
DEVELOPING SURFACE LOW LEE OF THE ROCKIES STRENGTHENS HELPING TO
DRAW DRIER AIR NORTHEASTWARD INTO SOUTHWEST KANSAS.

TEMPERATURES WILL BE SLIGHTLY WARMER GOING INTO MONDAY AS SURFACE
HIGH PRESSURE DROPS SOUTHEAST OUT OF THE NORTHERN PLAINS INTO THE
MID MISSISSIPPI RIVER VALLEY. THIS WILL HELP KEEP A SOUTHEASTERLY
LOW LEVEL FLOW IN PLACE ACROSS WESTERN KANSAS ALLOWING FOR SOME
MODEST WARM AIR ADVECTION. THE NAM, GFS, AND ECMWF SHOW H85
TEMPERATURES RANGING FROM THE MID TEENS(C) ACROSS CENTRAL KANSAS
TO NEAR 20C ALONG THE COLORADO BORDER. LOOK FOR HIGHS TO BE NEAR
TO JUST ABOVE 80F MONDAY AFTERNOON WITH A FEW UPPER 70S(F) STILL
POSSIBLE IN SOME LOCATIONS...MAINLY IN CENTRAL KANSAS. THE WARMING
TREND WILL CONTINUE INTO TUESDAY AS LEE SIDE TROUGHING STRENGTHENS
ACROSS EASTERN COLORADO. ENHANCED WARM AIR ADVECTION WITHIN A
STRONGER SOUTH TO SOUTHWESTERLY FLOW WILL RAISE H85 TEMPERATURES
UP TO NEAR 20C ACROSS CENTRAL KANSAS TO THE UPPER 20S(C) ACROSS
FAR SOUTHWEST KANSAS. EXPECT HIGHS FROM THE MID TO UPPER 80S(F) IN
CENTRAL KANSAS TUESDAY AFTERNOON TO THE LOWER TO MID 90S(F) IN
EXTREME SOUTHWEST KANSAS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1257 AM CDT SUN MAY 20 2012

WILL SHOW SOME SCATTERED TO BROKEN MID/UPPER LEVEL CLOUDINESS ACROSS
CENTRAL AND SOUTHWEST KANSAS THROUGH THE EARLY MORNING HOURS AS A WEAK
DISTURBANCE MOVES OVER THE AREA. AN ASSOCIATED SMALL AREA OF LIGHT RAIN
SHOWERS OR SPRINKLES WILL ALSO MOVE THROUGH THE AREA. THIS PRECIPITATION
IS VERY LIGHT SO VISIBILITIES SHOULD REMAIN IN THE VFR CATEGORY. NORTHERLY
WINDS MAY BECOME GUSTY FOR A TIME AFTER SUNRISE BUT SHOULD DECREASE
AGAIN AND SWITCH AROUND TO THE NORTHEAST AFTER 18Z.


&&

.PRELIMINARY POINT TEMPS/POPS...
DDC  77  55  81  60 /   0   0  10  10
GCK  76  54  81  60 /   0  10  10  10
EHA  76  56  82  60 /   0  10  20  20
LBL  77  57  82  61 /   0  10  20  20
HYS  76  53  81  60 /   0   0  10  10
P28  80  57  80  61 /   0  10  10  10

&&

.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...GERARD
SHORT TERM...GERARD
LONG TERM...JJOHNSON
AVIATION...GERARD







AREA FORECAST DISCUSSION

NWS WICHITA KS

 1155 PM CDT SAT MAY 19 2012

.AVIATION...06Z TAFS KRSL/KSLN/KHUT/KICT/KCNU

LINGERING CONVECTION WILL FESTER OVER SOUTHEAST KS
OVERNIGHT...AFFECTING MAINLY KCNU AND POSSIBLY KICT...AS COLD
FRONT CONTINUES TO SLOWLY ADVANCE SOUTHEAST. CANNOT RULE OUT A FEW
SHOWERS/THUNDERSTORMS OVER FAR SOUTHERN KS SUNDAY ALONG MID-LEVEL
BAROCLINIC ZONE...WHICH COULD FLIRT WITH KICT-KCNU. LEFT OUT OF
TAFS FOR NOW.

ADK

&&

.PREV DISCUSSION... /ISSUED 959 PM CDT SAT MAY 19 2012/

UPDATE...

STRONG/SEVERE STORMS ARE HANGING AROUND A BIT LONGER THAN
PREVIOUSLY EXPECTED...AND ARE REMAINING FAIRLY STOUT FURTHER EAST
THAN PREVIOUSLY THOUGHT...DESPITE SHARPLY DECREASING INSTABILITY
EAST OF THE FLINT HILLS AND A STOUT CAPPING INVERSION PER TOPEKA
AND SPRINGFIELD EVENING SOUNDINGS. ONE POSSIBILITY FOR THE RECENT
70-80 MPH WIND GUST OVER GREENWOOD COUNTY IS EVAPORATIVE COOLING
DUE TO DRY LOW-LEVELS. ACTIVITY OVER SOUTH-CENTRAL KANSAS ALONG
THE OK BORDER IS STILL ABLE TO TAP A MODESTLY UNSTABLE
AIRMASS TO THE SOUTH OF THE COLD FRONT...SO STRONG/SEVERE MAKES
SENSE THERE. OVERALL TREND SHOULD BE FOR A GRADUAL DECREASE IN
THUNDERSTORM INTENSITY...ALTHOUGH COVERAGE COULD STAY UP DUE TO
LOW-LEVEL JET ACTING ON COLD FRONT. WILL CONTINUE SEVERE
THUNDERSTORM WATCH GENERALLY SOUTHEAST OF THE KS TURNPIKE IN
EFFECT UNTIL 4 AM...ALTHOUGH ENVISION OVERNIGHT SHIFT WILL BE ABLE
TO CANCEL EARLY.

ADK

PREV DISCUSSION... /ISSUED 805 PM CDT SAT MAY 19 2012/

UPDATE...

IT APPEARS TORNADO THREAT IS RAPIDLY WANING AS LOW-LEVEL CAPE
DECREASES DUE TO ONSET OF DIURNAL COOLING.
ADDITIONALLY...MAGNITUDE OF SEVERE WEATHER SHOULD GRADUALLY WANE
WITH EASTWARD EXTENT...AS LOW-LEVEL THETA-E AND INSTABILITY DROPS
OFF SHARPLY EAST OF THE FLINT HILLS. HOWEVER...DID END UP
INCLUDING GREENWOOD-ELK-CHAUTAUQUA-COWLEY COUNTIES IN THE SEVERE
THUNDERSTORM WATCH UNTIL 10 PM. SUB-SEVERE SHOWERS/THUNDERSTORMS
COULD CONTINUE REDEVELOPING/FESTERING OVER PORTIONS OF
CENTRAL/SOUTH- CENTRAL KS IN WAKE OF THE SURFACE COLD
FRONT...ALONG ELEVATED FRONTAL SURFACE PUSHING EAST.

ADK

PREV DISCUSSION... /ISSUED 659 PM CDT SAT MAY 19 2012/

AVIATION...00Z TAFS KRSL/KSLN/KHUT/KICT/KCNU

SCATTERED STRONG/SEVERE STORMS ALONG AN EASTWARD ADVANCING COLD
FRONT WILL CONTINUE MOVING EAST/NORTHEAST THIS
EVENING...AFFECTING KSLN-KICT WITHIN THE NEXT FEW HOURS AND
POSSIBLY KHUT. VERY HEAVY RAIN...GUSTY WINDS AND HAIL CAN BE
EXPECTED. THREAT SHOULD PASS KHUT-KICT-KSLN BY 02-03Z OR SO...WITH
THUNDERSTORMS MAYBE NOT EVEN MAKING IT TO KCNU. WILL CONTINUE TO
MONITOR.

ADK

PREV DISCUSSION... /ISSUED 314 PM CDT SAT MAY 19 2012/

DISCUSSION...

SYNOPSIS...SURFACE LOW PRESSURE WAS CENTERED NEAR GREAT BEND AT
18Z.  THIS LOW WAS PART OF A COLD FRONT THAT EXTENDED FROM CENTRAL
MINNESOTA /AND AREAS FURTHER NORTH/...TO THE TEXAS PANHANDLE.

A STRONG UPPER LEVEL DISTURBANCE WAS ADVANCING NORTHEASTWARD ACROSS
SOUTHWEST NEBRASKA.  THIS WILL BRING DESTABILIZING COOLER AIR IN THE
MID LEVELS TO THE REGION...CAUSING SHOWERS AND THUNDERSTORMS TO
DEVELOP ALONG THE FRONT.  THESE ARE ALSO A BIG PART OF THE STORMS
ONGOING ACROSS WESTERN KANSAS AND WESTERN NEBRASKA. AS OF
1945Z...THE LEADING EDGE OF THIS CAN BE SEEN WELL ON WATER VAPOR
MOVING ACROSS WESTERN KANSAS.

TONIGHT...
THE FRONT WILL CONTINUE MOVING SOUTHEAST THIS EVENING.  RUC SHOWING
SIGNIFICANT COLD ADVECTION ONGOING WITH THE APPROACHING
DISTURBANCE.  DURING THE DAY...THE CONVERGENCE ALONG THE FRONT HAS HAD A
HARD TIME GETTING GOING AS THE WINDS HAVE VEERED AHEAD OF THE
FRONT.  THIS HAS ADDED TO THE UNCERTAINTY OF WHEN CONVECTION IS
EXPECTED TO DEVELOP...BUT SHOULD BE BY 23Z.  0-6KM SHEAR IS MARGINAL
FOR ORGANIZED CONVECTION...WITH VALUES RANGING FROM 30-35 KNOTS.
THAT SAID...THERE IS ENOUGH INSTABILITY FOR SOME OF THE STORMS TO
BECOME SEVERE.

SUNDAY...THE FRONT SHOULD MAKE IT WELL INTO SOUTHEAST KANSAS.  WITH
THE MAIN UPPER LEVEL SUPPORT FAR REMOVED FROM THE FRONT...ORGANIZED
SEVERE STORMS LOOK UNLIKELY AT THIS TIME...THOUGH SOME SCATTERED
STORMS EXPECTED.

MONDAY-SATURDAY...
HIGH PRESSURE WILL REMAIN ACROSS THE REGION THROUGH TUESDAY. THE
FRONT THAT JUST MOVED THROUGH WILL RETREAT NORTHWARD AS A WARM
FRONT. LEE CYCLOGENESIS TAKES PLACE AND BY WEDNESDAY...STRONG
SOUTHWESTERLY WINDS DEVELOP AGAIN AT THE SURFACE.  THIS WILL ALL
RESULT IN A WARMING TREND IN THE MIDDLE AND LATTER PORTION OF THE
WEEK.  BY FRIDAY...A DEEP UPPER LEVEL TROUGH DEVELOPS OVER THE
PACIFIC COAST WITH RIDGING OVER THE SOUTHEAST.  THIS WILL KEEP ALL
OF THE SIGNIFICANT PRECIPITATION WELL TO THE NORTH.

COOK

AVIATION...18Z TAFS KRSL/KSLN/KHUT/KICT/KCNU

MAIN HAZARDS: WINDS AHEAD OF/BEHIND COLD FRONT...AND THUNDERSTORMS.

S-SWRLY GUSTS 25-35KT WILL PERSIST AHEAD OF FRONT THIS PM/EARLY
EVE. COLD FRONT SHOULD REACH RSL AROUND 20-21Z...SLN/HUT
01-02Z...AND ICT ~03-04Z. SCATTERED-BROKEN LINE OF THUNDERSTORMS
SHOULD DEVELOP ALONG THE FRONT LATE THIS PM/EVE WHICH COULD
PRODUCE OUTFLOW AHEAD OF ACTUAL FRONT. WIND GUSTS 40-50 KT AND
HAIL WOULD BE THE MAIN THREATS FROM THESE STORMS. WILL CARRY TEMPO
TS AT HUT/SLN SITES WITH HIGHEST CONFIDENCE OF STORMS AFFECTING
THOSE SITES...AND VCTS AT ICT. WIND SHIFT TO NW WITH SOME GUSTS
20-25 KT THIS EVE IN CENTRAL/SOUTH CENTRAL KS.

JMC

&&

.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT    58  79  57  80 /  60  20  10   0
HUTCHINSON      56  78  54  80 /  60  10   0   0
NEWTON          57  77  53  78 /  60  20  10   0
ELDORADO        59  78  54  79 /  60  20  10   0
WINFIELD-KWLD   61  79  58  80 /  60  30  20  10
RUSSELL         52  77  51  81 /  10  10   0   0
GREAT BEND      53  78  52  81 /  10  10   0   0
SALINA          56  78  51  80 /  60  10   0   0
MCPHERSON       57  77  52  79 /  60  10   0   0
COFFEYVILLE     65  81  59  79 /  40  40  30  10
CHANUTE         64  79  57  78 /  50  40  10  10
IOLA            64  78  57  77 /  50  40  10  10
PARSONS-KPPF    65  80  58  78 /  50  40  20  10

&&

.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$








AREA FORECAST DISCUSSION

NWS JACKSON KY

 111 PM EDT SUN MAY 20 2012

.UPDATE...
ISSUED AT 111 PM EDT SUN MAY 20 2012

VISIBLE SATELLITE SHOWS CU FIELD HAS BECOME MORE EXTENSIVE OVER THE
CUMBERLAND PLATEAU OF TN AND NORTHWARD INTO THE SW PART OF OUR
FORECAST AREA. A FEW RADAR RETURNS ALSO BEGINNING TO POP UP...MAINLY
W AND S OF FORECAST AREA. HAVE ADDED ISOLATED SHOWERS AND
THUNDERSTORMS IN THE FORECAST GRIDS OVER THE SOUTHWEST PART OF
FORECASTA AREA AND HAVE ALSO UPDATED THE ZFP.

UPDATE ISSUED AT 1131 AM EDT SUN MAY 20 2012

UPDATED THE NDFD FOR LATEST OBSERVATIONAL TRENDS. MADE SOME MINOR
ADJUSTMENTS TO AFTERNOON MAXIMUM TEMPERATURES IN A FEW SPOTS...WITH A
FEW SPOTS MAINLY IN THE SOUTH LOWERED SLIGHTLY...AND A FEW SPOTS
MAINLY IN THE NORTH INCREASED SLIGHTLY. THESE CHANGES WERE MINOR AND
DID NOT AFFECT THE ZFP...BUT THE ZFP WAS SENT TO UPDATE AFTERNOON
WORDING. HAVE DECIDED TO CONTINUE WITH THE ISOLATED...20 PERCENT
CHANCE OF SHOWERS AND THUNDERSTORMS IN THE HIGHER TERRAIN ALONG THE
VA BORDER...WITH THIS IDEA SUPPORTED BY THE 12Z NAM. THE RECENT RUNS
OF THE HRRR STILL SHOWING ISOLATED CONVECTION THIS AFTERNOON OVER THE
WESTERN PART OF THE FORECAST AREA...BUT NOT QUITE AS MUCH AS EARLIER
RUNS. DID NOT EXPAND THE AREA OF SLIGHT CHANCE THUNDERSTORMS
FROM THE CURRENT AREA BUT WILL CONTINUE TO MONITOR.

UPDATE ISSUED AT 942 AM EDT SUN MAY 20 2012

HAVE UPDATED NDFD FOR LATEST OBSERVATIONAL TRENDS...MAKING ONLY MINOR
MODIFICATIONS TO THE FORECAST DATABASE. SATELLITE SHOWS THE HIGH
CLOUDINESS OVER E KY THINNING. EXPECT THINNING TO CONTINUE PER
LATEST SATELLITE TRENDS...WITH THIS IDEA SUPPORTED BY 06Z NAM
GUIDANCE. MAIN QUESTION TO RESOLVE FOR THIS AFTERNOON IS WHETHER
THERE WILL BE ANY ISOLATED CONVECTION AND WHERE IT WOULD BE. FOR NOW
HAVE DECIDED TO CONTINUE WITH THE PREVIOUS FORECAST OF ISOLATED
CONVECTION FOR LETCHER...HARLAN AND BELL COUNTIES.

HOWEVER THERE ARE INDICATIONS ISOLATED CONVECTION COULD DEVELOP
FURTHER WEST...MORE ALONG THE EDGE OF WHERE THE HIGH CLOUD HAS BEEN.
VISIBLE SATELLITE SHOWING CU OVER PARTS OF E AND CENTRAL KY WEST OF A
LINE FROM CAMPTON TO MIDDLESBORO. CAN SEE THE CU THAT IS JUST WEST
OF JACKSON FROM THE NWS OFFICE. THE RECENT RUNS OF THE HRRR HAVE
POINTED TOWARDS ISOLATED CONVECTION WEST OF A LINE FROM SANDY HOOK TO
HARLAN THIS AFTERNOON. THINK THE NORTHERN EXTENT OF THIS MAY BE OVERDONE...AS
THERE WAS A SLIGHT CAP IN THE ILN SOUNDING...BUT THE NASHVILLE
SOUNDING WAS NOT CAPPED. THE SREF SUPPORTS THE IDEA OF CONVECTION
OVER OUR SW COUNTIES THIS AFTERNOON...AND THE HRRR INDICATES THE
GREATEST COVERAGE IN OUR FORECAST AREA WOULD BE OVER THE SOUTHWEST.
WILL MONITOR AS THE MORNING CONTINUES...AND MAY ADD ISOLATED
CONVECTION ALONG OUR SOUTHERN BORDER ALL THE WAY TO LAKE CUMBERLAND.

UPDATE ISSUED AT 638 AM EDT SUN MAY 20 2012

LOT MORE HIGH CLOUDS DEVELOPING UPSTREAM OVER THE PAST FEW HOURS. IF
THE HIGH CLOUDS PERSIST LIKE THEY APPEAR TO BE...WE MAY NOT DEVELOP
AS MUCH CU TODAY...AND THUS THE ISOLATED SHOWER/THUNDERSTORM CHANCES
IN THE SOUTHEAST COULD BE IN JEOPARDY. HOWEVER...STILL TIME FOR THIS
TO CHANGE...AND WON`T MAKE ANY CHANGES AT THIS TIME. ONCOMING
DAYSHIFT CAN REEVALUATE THE NEED FOR POPS IN THE SOUTHEAST.
OTHERWISE...TWEAKED MORNING TEMPERATURES AND DEWPOINTS TO BETTER
MATCH UP WITH OBSERVATIONS. THESE CHANGES WERE VERY MINOR...SO NO
NEED TO SEND OUT AN UPDATED FORECAST AT THIS TIME.

&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 305 AM EDT SUN MAY 20 2012

TROPICAL STORM ALBERTA CONTINUES TO SPIN OFF THE SOUTH CAROLINA COAST
THIS MORNING WITH A MID LEVEL TROUGH PUSHING ACROSS THE CENTRAL
PLAINS. BETWEEN THESE TWO SYSTEMS...A STRONG RIDGE OF HIGH PRESSURE
CONTINUES TO PRODUCE QUIET WEATHER FROM THE GREAT LAKES...SOUTHWARD
INTO THE OHIO VALLEY. THE SETUP WILL REMAIN VERY SIMILAR TO
YESTERDAY...WITH ANOTHER ROUND OF ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS DEVELOPING ACROSS THE TENNESSEE VALLEY REGION AS STRONG
INSTABILITY DEVELOPS MY MID AFTERNOON. MUCH LIKE YESTERDAY...A FEW
SHOWERS OR STORMS COULD SCRAPE THE COUNTIES IN KENTUCKY NEAR THE
VIRGINIA AND TENNESSEE BORDERS THIS AFTERNOON. THUS...WENT WITH
ISOLATED COVERAGE AS ANY SHOWERS AND STORMS WILL NOT AFFECT ANY LARGE
AREAS. THE SHOWERS AND STORMS WILL DISSIPATE BY SUNSET.

MEANWHILE...THE MID LEVEL TROUGH TO OUR WEST WILL PUSH INTO WESTERN
AND CENTRAL KENTUCKY LATE TONIGHT. SHOWERS AND PERHAPS A FEW
THUNDERSTORMS MAY ACCOMPANY THIS FEATURE...BUT ARE EXPECTED TO BE
WEAKENING AS THEY OUTRUN THE BETTER MID LEVEL SUPPORT. A FEW OF THESE
SHOWERS OR STORMS COULD SNEAK INTO OUR SOUTHWEST COUNTIES AROUND
DAYBREAK MONDAY. AS THE SHORTWAVE TROUGH PUSHES INTO THE OHIO VALLEY
ON MONDAY...THIS WILL PROVIDE BETTER MID/UPPER LEVEL SUPPORT FOR
SHOWER AND THUNDERSTORM DEVELOPMENT. IN ADDITION...INSTABILITY IS
EXPECTED TO INCREASE ACROSS THE REGION. THIS COMBINATION WILL LEAD TO
THE DEVELOPMENT OF A LINE OF SHOWERS AND STORMS AND WILL TRACK
EASTWARD ACROSS THE AREA MONDAY AFTERNOON. SHEAR IS VERY WEAK...IF
NOT NON-EXISTENT...SO NO THREAT FOR ANY SEVERE STORMS THIS TIME
AROUND. THIS LINE WILL WEAKEN AND DISSIPATE AS IT PUSHES TO OUR EAST
MONDAY NIGHT. IN THE WAKE OF THIS ACTIVITY...NOT MUCH SUPPORT FOR
ADDITIONAL DEVELOPMENT...ALTHOUGH AN ISOLATED SHOWER OR STORM IS
STILL POSSIBLE AS THE MID LEVEL THROUGH REMAINS ANCHORED ACROSS OUR
REGION. WENT WITH LIKELY POPS ON MONDAY WITH THE GOOD DYNAMICS AND
INSTABILITY AROUND...AND DROPPED POPS BACK TO MAINLY SLIGHT CHANCE
FOR MONDAY NIGHT.

.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 305 AM EDT SUN MAY 20 2012

THE MODELS CONTINUE TO HAVE SOME DIFFERENCES ALOFT WITH THE TROUGH
DIVING THROUGH THE OHIO VALLEY AT THE START OF THE EXTENDED. THE NAM
APPEARS TO BE THE MAIN OUTLIER HERE WITH A DEEPER AND SLOWER CLOSED
LOW SETTLING INTO OHIO THAN THE OTHER MODELS. BY CONTRAST THEY
REMAIN PROGRESSIVE INTO WEDNESDAY...THOUGH THE ECMWF DOES CLOSE OFF
A WEAKER VERSION OF ITS LOW FROM YESTERDAY OVER THE SOUTHERN
APPALACHIANS. THE GFS...IN CONTRAST...BRINGS IN RIDGING DURING THIS
TIME KEEPING JUST A WEAK HINT OF A LOW WELL EAST OF THE OTHER
MODELS. BY THURSDAY MORNING...THE ECMWF TAKES THE UPPER LOW EAST...
THOUGH IT STILL LAGS THE OTHER MODELS. THROUGH THE FIRST PART OF THE
EXTENDED...A BLEND IS PREFERRED...WITH SOME FAVORING THE
SLOWER/DEEPER ECMWF SOLUTION. LATER...THOUGH...THE MODELS ARE IN
BETTER AGREEMENT...AT LEAST LOCALLY...WITH RIDGING BUILDING OVERHEAD
IN RESPONSE TO A DEEP LOW PUSHING ASHORE ON THE WEST COAST. THIS
RIDGE SHOULD PROVIDE A PROTECTIVE DOME OVER THE OHIO VALLEY AND EAST
KENTUCKY HEADING INTO THE WEEKEND WHILE SHORTWAVES MOVE PAST WELL TO
THE NORTH.

SENSIBLE WEATHER WILL FEATURE STILL DECENT CHANCES OF SHOWERS AND
THUNDERSTORMS DURING THE DAY TUESDAY...FAVORING THE EAST...BENEATH
THE UPPER LOW AND ITS WEAK SFC REFLECTION OVER THE EASTERN OHIO
VALLEY. HAVE GONE WITH A DIURNAL PEAK IN THE MID TO LATE AFTERNOON
FOR POPS AND SKY COVER. A SMALL THREAT FOR CONVECTION WILL REMAIN IN
THE AREA ON WEDNESDAY AS WEAK HIGH PRESSURE SLOWLY BUILDS INTO THE
AREA FROM THE WEST AND THE UPPER LOW STARTS TO FILL AND MOVE OFF TO
THE EAST. THE CLOUDS AND PCPN WILL BE ENOUGH TO KEEP TEMPERATURES ON
THE COOL SIDE OF NORMAL FOR MOST PLACES TUESDAY AND WEDNESDAY BEFORE
A SIGNIFICANT WARMUP BEGINS IN EARNEST FRIDAY WITH THE ARRIVAL OF
SFC HIGH PRESSURE AND RIDGING ALOFT. THESE WILL COMBINE TO LIMIT
PCPN CHANCES THROUGH THE REMAINDER OF THE EXTENDED AND ALLOW
TEMPERATURES TO TAKE A RUN AT 90 DEGREES IN MANY EAST KENTUCKY
LOCATIONS BY SATURDAY AFTERNOON.

THE GRID LOAD CAME IN FAIRLY DECENT WITH A REASONABLE EMPHASIS ON
THE ECMWF SOLUTION. DID FINE TUNE THE POPS THROUGH WEDNESDAY FOR
MORE OF A DIURNAL FACTOR AND LESS IN THE SOUTHWEST THAN WAS LOADED.
ALSO...ADDED SOME USUAL TERRAIN BASED DETAILS TO THE LOW TEMPERATURE
GRIDS WEDNESDAY THROUGH FRIDAY NIGHT AS WE CONTINUE TO DRY OUT AND
SOUTHWEST FLOW KICKS IN.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 111 PM EDT SUN MAY 20 2012

ISOLATED SHOWERS HAVE DEVELOPED ACROSS THE FAR SW PART OF FORECAST
AREA IN THE LAKE CUMBERLAND AREA AS OF 17Z...WITH MORE CONVECTION S AND
WEST OF THE FORECAST AREA. EXPECT MOST SHOWERS AND THUNDERSTORMS TO
BE REMAIN S OR SW OF SME AND LOZ...AND WILL NOT MENTION IN THE TAFS.
ANY CONVECTION WILL DISSIPATE THIS EVENING...BUT EXPECT SOME FOG TO
DEVELOP IN VALLEYS AND OPEN AREAS LATE TONIGHT. HAVE INTRODUCED MVFR
VSIBILITY WITH FOG IN THE LOZ AND SME TAFS FOR LATE TONIGHT AND EARLY
MONDAY MORNING. RIDGE TOP AIRPORTS SUCH AS JKL SHOULD REMAIN FOG
FREE. A COLD FRONT WILL BE APPROACHING THE REGION ON MONDAY...AND
THIS WILL BRING MORE ORGANIZED SHOWERS AND THUNDERSTORMS FROM MONDAY
AFTERNOON INTO MONDAY NIGHT.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...SBH
SHORT TERM...KAS
LONG TERM....GREIF
AVIATION...SBH







AREA FORECAST DISCUSSION

NWS JACKSON KY

 1132 AM EDT SUN MAY 20 2012

.UPDATE...
ISSUED AT 1131 AM EDT SUN MAY 20 2012

UPDATED THE NDFD FOR LATEST OBSERVATIONAL TRENDS. MADE SOME MINOR
ADJUSTMENTS TO AFTERNOON MAXIMUM TEMPERATURES IN A FEW SPOTS...WITH A
FEW SPOTS MAINLY IN THE SOUTH LOWERED SLIGHTLY...AND A FEW SPOTS
MAINLY IN THE NORTH INCREASED SLIGHTLY. THESE CHANGES WERE MINOR AND
DID NOT AFFECT THE ZFP...BUT THE ZFP WAS SENT TO UPDATE AFTERNOON
WORDING. HAVE DECIDED TO CONTINUE WITH THE ISOLATED...20 PERCENT
CHANCE OF SHOWERS AND THUNDERSTORMS IN THE HIGHER TERRAIN ALONG THE
VA BORDER...WITH THIS IDEA SUPPORTED BY THE 12Z NAM. THE RECENT RUNS
OF THE HRRR STILL SHOWING ISOLATED CONVECTION THIS AFTERNOON OVER THE
WESTERN PART OF THE FORECAST AREA...BUT NOT QUITE AS MUCH AS EARLIER
RUNS. DID NOT EXPAND THE AREA OF SLIGHT CHANCE THUNDERSTORMS
FROM THE CURRENT AREA BUT WILL CONTINUE TO MONITOR.

UPDATE ISSUED AT 942 AM EDT SUN MAY 20 2012

HAVE UPDATED NDFD FOR LATEST OBSERVATIONAL TRENDS...MAKING ONLY MINOR
MODIFICATIONS TO THE FORECAST DATABASE. SATELLITE SHOWS THE HIGH
CLOUDINESS OVER E KY THINNING. EXPECT THINNING TO CONTINUE PER
LATEST SATELLITE TRENDS...WITH THIS IDEA SUPPORTED BY 06Z NAM
GUIDANCE. MAIN QUESTION TO RESOLVE FOR THIS AFTERNOON IS WHETHER
THERE WILL BE ANY ISOLATED CONVECTION AND WHERE IT WOULD BE. FOR NOW
HAVE DECIDED TO CONTINUE WITH THE PREVIOUS FORECAST OF ISOLATED
CONVECTION FOR LETCHER...HARLAN AND BELL COUNTIES.

HOWEVER THERE ARE INDICATIONS ISOLATED CONVECTION COULD DEVELOP
FURTHER WEST...MORE ALONG THE EDGE OF WHERE THE HIGH CLOUD HAS BEEN.
VISIBLE SATELLITE SHOWING CU OVER PARTS OF E AND CENTRAL KY WEST OF A
LINE FROM CAMPTON TO MIDDLESBORO. CAN SEE THE CU THAT IS JUST WEST
OF JACKSON FROM THE NWS OFFICE. THE RECENT RUNS OF THE HRRR HAVE
POINTED TOWARDS ISOLATED CONVECTION WEST OF A LINE FROM SANDY HOOK TO
HARLAN THIS AFTERNOON. THINK THE NORTHERN EXTENT OF THIS MAY BE OVERDONE...AS
THERE WAS A SLIGHT CAP IN THE ILN SOUNDING...BUT THE NASHVILLE
SOUNDING WAS NOT CAPPED. THE SREF SUPPORTS THE IDEA OF CONVECTION
OVER OUR SW COUNTIES THIS AFTERNOON...AND THE HRRR INDICATES THE
GREATEST COVERAGE IN OUR FORECAST AREA WOULD BE OVER THE SOUTHWEST.
WILL MONITOR AS THE MORNING CONTINUES...AND MAY ADD ISOLATED
CONVECTION ALONG OUR SOUTHERN BORDER ALL THE WAY TO LAKE CUMBERLAND.

UPDATE ISSUED AT 638 AM EDT SUN MAY 20 2012

LOT MORE HIGH CLOUDS DEVELOPING UPSTREAM OVER THE PAST FEW HOURS. IF
THE HIGH CLOUDS PERSIST LIKE THEY APPEAR TO BE...WE MAY NOT DEVELOP
AS MUCH CU TODAY...AND THUS THE ISOLATED SHOWER/THUNDERSTORM CHANCES
IN THE SOUTHEAST COULD BE IN JEOPARDY. HOWEVER...STILL TIME FOR THIS
TO CHANGE...AND WON`T MAKE ANY CHANGES AT THIS TIME. ONCOMING
DAYSHIFT CAN REEVALUATE THE NEED FOR POPS IN THE SOUTHEAST.
OTHERWISE...TWEAKED MORNING TEMPERATURES AND DEWPOINTS TO BETTER
MATCH UP WITH OBSERVATIONS. THESE CHANGES WERE VERY MINOR...SO NO
NEED TO SEND OUT AN UPDATED FORECAST AT THIS TIME.

&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 305 AM EDT SUN MAY 20 2012

TROPICAL STORM ALBERTA CONTINUES TO SPIN OFF THE SOUTH CAROLINA COAST
THIS MORNING WITH A MID LEVEL TROUGH PUSHING ACROSS THE CENTRAL
PLAINS. BETWEEN THESE TWO SYSTEMS...A STRONG RIDGE OF HIGH PRESSURE
CONTINUES TO PRODUCE QUIET WEATHER FROM THE GREAT LAKES...SOUTHWARD
INTO THE OHIO VALLEY. THE SETUP WILL REMAIN VERY SIMILAR TO
YESTERDAY...WITH ANOTHER ROUND OF ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS DEVELOPING ACROSS THE TENNESSEE VALLEY REGION AS STRONG
INSTABILITY DEVELOPS MY MID AFTERNOON. MUCH LIKE YESTERDAY...A FEW
SHOWERS OR STORMS COULD SCRAPE THE COUNTIES IN KENTUCKY NEAR THE
VIRGINIA AND TENNESSEE BORDERS THIS AFTERNOON. THUS...WENT WITH
ISOLATED COVERAGE AS ANY SHOWERS AND STORMS WILL NOT AFFECT ANY LARGE
AREAS. THE SHOWERS AND STORMS WILL DISSIPATE BY SUNSET.

MEANWHILE...THE MID LEVEL TROUGH TO OUR WEST WILL PUSH INTO WESTERN
AND CENTRAL KENTUCKY LATE TONIGHT. SHOWERS AND PERHAPS A FEW
THUNDERSTORMS MAY ACCOMPANY THIS FEATURE...BUT ARE EXPECTED TO BE
WEAKENING AS THEY OUTRUN THE BETTER MID LEVEL SUPPORT. A FEW OF THESE
SHOWERS OR STORMS COULD SNEAK INTO OUR SOUTHWEST COUNTIES AROUND
DAYBREAK MONDAY. AS THE SHORTWAVE TROUGH PUSHES INTO THE OHIO VALLEY
ON MONDAY...THIS WILL PROVIDE BETTER MID/UPPER LEVEL SUPPORT FOR
SHOWER AND THUNDERSTORM DEVELOPMENT. IN ADDITION...INSTABILITY IS
EXPECTED TO INCREASE ACROSS THE REGION. THIS COMBINATION WILL LEAD TO
THE DEVELOPMENT OF A LINE OF SHOWERS AND STORMS AND WILL TRACK
EASTWARD ACROSS THE AREA MONDAY AFTERNOON. SHEAR IS VERY WEAK...IF
NOT NON-EXISTENT...SO NO THREAT FOR ANY SEVERE STORMS THIS TIME
AROUND. THIS LINE WILL WEAKEN AND DISSIPATE AS IT PUSHES TO OUR EAST
MONDAY NIGHT. IN THE WAKE OF THIS ACTIVITY...NOT MUCH SUPPORT FOR
ADDITIONAL DEVELOPMENT...ALTHOUGH AN ISOLATED SHOWER OR STORM IS
STILL POSSIBLE AS THE MID LEVEL THROUGH REMAINS ANCHORED ACROSS OUR
REGION. WENT WITH LIKELY POPS ON MONDAY WITH THE GOOD DYNAMICS AND
INSTABILITY AROUND...AND DROPPED POPS BACK TO MAINLY SLIGHT CHANCE
FOR MONDAY NIGHT.

.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 305 AM EDT SUN MAY 20 2012

THE MODELS CONTINUE TO HAVE SOME DIFFERENCES ALOFT WITH THE TROUGH
DIVING THROUGH THE OHIO VALLEY AT THE START OF THE EXTENDED. THE NAM
APPEARS TO BE THE MAIN OUTLIER HERE WITH A DEEPER AND SLOWER CLOSED
LOW SETTLING INTO OHIO THAN THE OTHER MODELS. BY CONTRAST THEY
REMAIN PROGRESSIVE INTO WEDNESDAY...THOUGH THE ECMWF DOES CLOSE OFF
A WEAKER VERSION OF ITS LOW FROM YESTERDAY OVER THE SOUTHERN
APPALACHIANS. THE GFS...IN CONTRAST...BRINGS IN RIDGING DURING THIS
TIME KEEPING JUST A WEAK HINT OF A LOW WELL EAST OF THE OTHER
MODELS. BY THURSDAY MORNING...THE ECMWF TAKES THE UPPER LOW EAST...
THOUGH IT STILL LAGS THE OTHER MODELS. THROUGH THE FIRST PART OF THE
EXTENDED...A BLEND IS PREFERRED...WITH SOME FAVORING THE
SLOWER/DEEPER ECMWF SOLUTION. LATER...THOUGH...THE MODELS ARE IN
BETTER AGREEMENT...AT LEAST LOCALLY...WITH RIDGING BUILDING OVERHEAD
IN RESPONSE TO A DEEP LOW PUSHING ASHORE ON THE WEST COAST. THIS
RIDGE SHOULD PROVIDE A PROTECTIVE DOME OVER THE OHIO VALLEY AND EAST
KENTUCKY HEADING INTO THE WEEKEND WHILE SHORTWAVES MOVE PAST WELL TO
THE NORTH.

SENSIBLE WEATHER WILL FEATURE STILL DECENT CHANCES OF SHOWERS AND
THUNDERSTORMS DURING THE DAY TUESDAY...FAVORING THE EAST...BENEATH
THE UPPER LOW AND ITS WEAK SFC REFLECTION OVER THE EASTERN OHIO
VALLEY. HAVE GONE WITH A DIURNAL PEAK IN THE MID TO LATE AFTERNOON
FOR POPS AND SKY COVER. A SMALL THREAT FOR CONVECTION WILL REMAIN IN
THE AREA ON WEDNESDAY AS WEAK HIGH PRESSURE SLOWLY BUILDS INTO THE
AREA FROM THE WEST AND THE UPPER LOW STARTS TO FILL AND MOVE OFF TO
THE EAST. THE CLOUDS AND PCPN WILL BE ENOUGH TO KEEP TEMPERATURES ON
THE COOL SIDE OF NORMAL FOR MOST PLACES TUESDAY AND WEDNESDAY BEFORE
A SIGNIFICANT WARMUP BEGINS IN EARNEST FRIDAY WITH THE ARRIVAL OF
SFC HIGH PRESSURE AND RIDGING ALOFT. THESE WILL COMBINE TO LIMIT
PCPN CHANCES THROUGH THE REMAINDER OF THE EXTENDED AND ALLOW
TEMPERATURES TO TAKE A RUN AT 90 DEGREES IN MANY EAST KENTUCKY
LOCATIONS BY SATURDAY AFTERNOON.

THE GRID LOAD CAME IN FAIRLY DECENT WITH A REASONABLE EMPHASIS ON
THE ECMWF SOLUTION. DID FINE TUNE THE POPS THROUGH WEDNESDAY FOR
MORE OF A DIURNAL FACTOR AND LESS IN THE SOUTHWEST THAN WAS LOADED.
ALSO...ADDED SOME USUAL TERRAIN BASED DETAILS TO THE LOW TEMPERATURE
GRIDS WEDNESDAY THROUGH FRIDAY NIGHT AS WE CONTINUE TO DRY OUT AND
SOUTHWEST FLOW KICKS IN.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 638 AM EDT SUN MAY 20 2012

AFTER MORNING FOG BURNS OFF...VFR CONDITIONS WILL PREVAIL ACROSS
EASTERN KENTUCKY THROUGH THIS EVENING. DEPENDING ON HOW WELL
DEWPOINTS CAN OR CANNOT MIX OUT THIS AFTERNOON...WE COULD BE LOOKING
AT ANOTHER NIGHT OF PATCHY VALLEY FOG...MAINLY IMPACTING KLOZ WITH
ANOTHER BRIEF PERIOD OF MVFR FOG EARLY TOMORROW MORNING.
HOWEVER...WITH DRIER AIR OFF TO OUR EAST...IF SOME OF THIS CAN ADVECT
INTO OUR REGION TODAY...THE FOG THREAT MAY BE MUCH LESS TONIGHT.
OTHERWISE...HIGH CLOUDS WILL DOMINATE THE SKIES TODAY...BUT IF WE CAN
THIN OUT THESE CLOUDS ENOUGH...WE COULD GET SOME 5-6KFT CU TO
DEVELOP.


&&

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...SBH
SHORT TERM...KAS
LONG TERM....GREIF
AVIATION...KAS







AREA FORECAST DISCUSSION

NWS JACKSON KY

 942 AM EDT SUN MAY 20 2012

.UPDATE...
ISSUED AT 942 AM EDT SUN MAY 20 2012

HAVE UPDATED NDFD FOR LATEST OBSERVATIONAL TRENDS...MAKING ONLY MINOR
MODIFICATIONS TO THE FORECAST DATABASE. SATELLITE SHOWS THE HIGH
CLOUDINESS OVER E KY THINNING. EXPECT THINNING TO CONTINUE PER
LATEST SATELLITE TRENDS...WITH THIS IDEA SUPPORTED BY 06Z NAM
GUIDANCE. MAIN QUESTION TO RESOLVE FOR THIS AFTERNOON IS WHETHER
THERE WILL BE ANY ISOLATED CONVECTION AND WHERE IT WOULD BE. FOR NOW
HAVE DECIDED TO CONTINUE WITH THE PREVIOUS FORECAST OF ISOLATED
CONVECTION FOR LETCHER...HARLAN AND BELL COUNTIES.

HOWEVER THERE ARE INDICATIONS ISOLATED CONVECTION COULD DEVELOP
FURTHER WEST...MORE ALONG THE EDGE OF WHERE THE HIGH CLOUD HAS BEEN.
VISIBLE SATELLITE SHOWING CU OVER PARTS OF E AND CENTRAL KY WEST OF A
LINE FROM CAMPTON TO MIDDLESBORO. CAN SEE THE CU THAT IS JUST WEST
OF JACKSON FROM THE NWS OFFICE. THE RECENT RUNS OF THE HRRR HAVE
POINTED TOWARDS ISOLATED CONVECTION WEST OF A LINE FROM SANDY HOOK TO
HARLAN THIS AFTERNOON. THINK THE NORTHERN EXTENT OF THIS MAY BE OVERDONE...AS
THERE WAS A SLIGHT CAP IN THE ILN SOUNDING...BUT THE NASHVILLE
SOUNDING WAS NOT CAPPED. THE SREF SUPPORTS THE IDEA OF CONVECTION
OVER OUR SW COUNTIES THIS AFTERNOON...AND THE HRRR INDICATES THE
GREATEST COVERAGE IN OUR FORECAST AREA WOULD BE OVER THE SOUTHWEST.
WILL MONITOR AS THE MORNING CONTINUES...AND MAY ADD ISOLATED
CONVECTION ALONG OUR SOUTHERN BORDER ALL THE WAY TO LAKE CUMBERLAND.

UPDATE ISSUED AT 638 AM EDT SUN MAY 20 2012

LOT MORE HIGH CLOUDS DEVELOPING UPSTREAM OVER THE PAST FEW HOURS. IF
THE HIGH CLOUDS PERSIST LIKE THEY APPEAR TO BE...WE MAY NOT DEVELOP
AS MUCH CU TODAY...AND THUS THE ISOLATED SHOWER/THUNDERSTORM CHANCES
IN THE SOUTHEAST COULD BE IN JEOPARDY. HOWEVER...STILL TIME FOR THIS
TO CHANGE...AND WON`T MAKE ANY CHANGES AT THIS TIME. ONCOMING
DAYSHIFT CAN REEVALUATE THE NEED FOR POPS IN THE SOUTHEAST.
OTHERWISE...TWEAKED MORNING TEMPERATURES AND DEWPOINTS TO BETTER
MATCH UP WITH OBSERVATIONS. THESE CHANGES WERE VERY MINOR...SO NO
NEED TO SEND OUT AN UPDATED FORECAST AT THIS TIME.

&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 305 AM EDT SUN MAY 20 2012

TROPICAL STORM ALBERTA CONTINUES TO SPIN OFF THE SOUTH CAROLINA COAST
THIS MORNING WITH A MID LEVEL TROUGH PUSHING ACROSS THE CENTRAL
PLAINS. BETWEEN THESE TWO SYSTEMS...A STRONG RIDGE OF HIGH PRESSURE
CONTINUES TO PRODUCE QUIET WEATHER FROM THE GREAT LAKES...SOUTHWARD
INTO THE OHIO VALLEY. THE SETUP WILL REMAIN VERY SIMILAR TO
YESTERDAY...WITH ANOTHER ROUND OF ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS DEVELOPING ACROSS THE TENNESSEE VALLEY REGION AS STRONG
INSTABILITY DEVELOPS MY MID AFTERNOON. MUCH LIKE YESTERDAY...A FEW
SHOWERS OR STORMS COULD SCRAPE THE COUNTIES IN KENTUCKY NEAR THE
VIRGINIA AND TENNESSEE BORDERS THIS AFTERNOON. THUS...WENT WITH
ISOLATED COVERAGE AS ANY SHOWERS AND STORMS WILL NOT AFFECT ANY LARGE
AREAS. THE SHOWERS AND STORMS WILL DISSIPATE BY SUNSET.

MEANWHILE...THE MID LEVEL TROUGH TO OUR WEST WILL PUSH INTO WESTERN
AND CENTRAL KENTUCKY LATE TONIGHT. SHOWERS AND PERHAPS A FEW
THUNDERSTORMS MAY ACCOMPANY THIS FEATURE...BUT ARE EXPECTED TO BE
WEAKENING AS THEY OUTRUN THE BETTER MID LEVEL SUPPORT. A FEW OF THESE
SHOWERS OR STORMS COULD SNEAK INTO OUR SOUTHWEST COUNTIES AROUND
DAYBREAK MONDAY. AS THE SHORTWAVE TROUGH PUSHES INTO THE OHIO VALLEY
ON MONDAY...THIS WILL PROVIDE BETTER MID/UPPER LEVEL SUPPORT FOR
SHOWER AND THUNDERSTORM DEVELOPMENT. IN ADDITION...INSTABILITY IS
EXPECTED TO INCREASE ACROSS THE REGION. THIS COMBINATION WILL LEAD TO
THE DEVELOPMENT OF A LINE OF SHOWERS AND STORMS AND WILL TRACK
EASTWARD ACROSS THE AREA MONDAY AFTERNOON. SHEAR IS VERY WEAK...IF
NOT NON-EXISTENT...SO NO THREAT FOR ANY SEVERE STORMS THIS TIME
AROUND. THIS LINE WILL WEAKEN AND DISSIPATE AS IT PUSHES TO OUR EAST
MONDAY NIGHT. IN THE WAKE OF THIS ACTIVITY...NOT MUCH SUPPORT FOR
ADDITIONAL DEVELOPMENT...ALTHOUGH AN ISOLATED SHOWER OR STORM IS
STILL POSSIBLE AS THE MID LEVEL THROUGH REMAINS ANCHORED ACROSS OUR
REGION. WENT WITH LIKELY POPS ON MONDAY WITH THE GOOD DYNAMICS AND
INSTABILITY AROUND...AND DROPPED POPS BACK TO MAINLY SLIGHT CHANCE
FOR MONDAY NIGHT.

.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 305 AM EDT SUN MAY 20 2012

THE MODELS CONTINUE TO HAVE SOME DIFFERENCES ALOFT WITH THE TROUGH
DIVING THROUGH THE OHIO VALLEY AT THE START OF THE EXTENDED. THE NAM
APPEARS TO BE THE MAIN OUTLIER HERE WITH A DEEPER AND SLOWER CLOSED
LOW SETTLING INTO OHIO THAN THE OTHER MODELS. BY CONTRAST THEY
REMAIN PROGRESSIVE INTO WEDNESDAY...THOUGH THE ECMWF DOES CLOSE OFF
A WEAKER VERSION OF ITS LOW FROM YESTERDAY OVER THE SOUTHERN
APPALACHIANS. THE GFS...IN CONTRAST...BRINGS IN RIDGING DURING THIS
TIME KEEPING JUST A WEAK HINT OF A LOW WELL EAST OF THE OTHER
MODELS. BY THURSDAY MORNING...THE ECMWF TAKES THE UPPER LOW EAST...
THOUGH IT STILL LAGS THE OTHER MODELS. THROUGH THE FIRST PART OF THE
EXTENDED...A BLEND IS PREFERRED...WITH SOME FAVORING THE
SLOWER/DEEPER ECMWF SOLUTION. LATER...THOUGH...THE MODELS ARE IN
BETTER AGREEMENT...AT LEAST LOCALLY...WITH RIDGING BUILDING OVERHEAD
IN RESPONSE TO A DEEP LOW PUSHING ASHORE ON THE WEST COAST. THIS
RIDGE SHOULD PROVIDE A PROTECTIVE DOME OVER THE OHIO VALLEY AND EAST
KENTUCKY HEADING INTO THE WEEKEND WHILE SHORTWAVES MOVE PAST WELL TO
THE NORTH.

SENSIBLE WEATHER WILL FEATURE STILL DECENT CHANCES OF SHOWERS AND
THUNDERSTORMS DURING THE DAY TUESDAY...FAVORING THE EAST...BENEATH
THE UPPER LOW AND ITS WEAK SFC REFLECTION OVER THE EASTERN OHIO
VALLEY. HAVE GONE WITH A DIURNAL PEAK IN THE MID TO LATE AFTERNOON
FOR POPS AND SKY COVER. A SMALL THREAT FOR CONVECTION WILL REMAIN IN
THE AREA ON WEDNESDAY AS WEAK HIGH PRESSURE SLOWLY BUILDS INTO THE
AREA FROM THE WEST AND THE UPPER LOW STARTS TO FILL AND MOVE OFF TO
THE EAST. THE CLOUDS AND PCPN WILL BE ENOUGH TO KEEP TEMPERATURES ON
THE COOL SIDE OF NORMAL FOR MOST PLACES TUESDAY AND WEDNESDAY BEFORE
A SIGNIFICANT WARMUP BEGINS IN EARNEST FRIDAY WITH THE ARRIVAL OF
SFC HIGH PRESSURE AND RIDGING ALOFT. THESE WILL COMBINE TO LIMIT
PCPN CHANCES THROUGH THE REMAINDER OF THE EXTENDED AND ALLOW
TEMPERATURES TO TAKE A RUN AT 90 DEGREES IN MANY EAST KENTUCKY
LOCATIONS BY SATURDAY AFTERNOON.

THE GRID LOAD CAME IN FAIRLY DECENT WITH A REASONABLE EMPHASIS ON
THE ECMWF SOLUTION. DID FINE TUNE THE POPS THROUGH WEDNESDAY FOR
MORE OF A DIURNAL FACTOR AND LESS IN THE SOUTHWEST THAN WAS LOADED.
ALSO...ADDED SOME USUAL TERRAIN BASED DETAILS TO THE LOW TEMPERATURE
GRIDS WEDNESDAY THROUGH FRIDAY NIGHT AS WE CONTINUE TO DRY OUT AND
SOUTHWEST FLOW KICKS IN.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 638 AM EDT SUN MAY 20 2012

AFTER MORNING FOG BURNS OFF...VFR CONDITIONS WILL PREVAIL ACROSS
EASTERN KENTUCKY THROUGH THIS EVENING. DEPENDING ON HOW WELL
DEWPOINTS CAN OR CANNOT MIX OUT THIS AFTERNOON...WE COULD BE LOOKING
AT ANOTHER NIGHT OF PATCHY VALLEY FOG...MAINLY IMPACTING KLOZ WITH
ANOTHER BRIEF PERIOD OF MVFR FOG EARLY TOMORROW MORNING.
HOWEVER...WITH DRIER AIR OFF TO OUR EAST...IF SOME OF THIS CAN ADVECT
INTO OUR REGION TODAY...THE FOG THREAT MAY BE MUCH LESS TONIGHT.
OTHERWISE...HIGH CLOUDS WILL DOMINATE THE SKIES TODAY...BUT IF WE CAN
THIN OUT THESE CLOUDS ENOUGH...WE COULD GET SOME 5-6KFT CU TO
DEVELOP.


&&

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...SBH
SHORT TERM...KAS
LONG TERM....GREIF
AVIATION...KAS







AREA FORECAST DISCUSSION

NWS GRAY ME

 1017 PM EDT MON MAY 21 2012

.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST TONIGHT AS LOW PRESSURE TRAVELS UP
THE EAST COAST. A COLD FRONT WILL APPROACH FROM THE WEST TOMORROW
TRIGGERING SHOWERS AND THUNDERSTORMS. THE REMAINDER OF THE WEEK WILL
BE WARM AND UNSETTLED WITH A CHANCE OF SHOWERS EACH DAY.

&&

.NEAR TERM /UNTIL 7 AM TUESDAY MORNING/...

10 PM UPDATE...HAVE UPDATED FORECASTS TO LOWER POPS ACROSS THE
REGION TO CHC OVERNIGHT AS MOST OF THE PRECIP REMAINS WEST OF THE
REGION. HAVE BUMPED UP TEMPS A BIT TO ACCOUNT FOR THE LACK OF
SHOWER ACTIVITY AND FOR WINDS KEEPING TEMPERATURES WARMER ACROSS
THE HIGHER TERRAIN. HAVE ALSO ENHANCED THE WORDING FOR DRIZZLE AND
FOG ACROSS COASTAL AREAS TONIGHT AND TUESDAY MORNING BASED ON
RECENT OBSERVATIONS.

3:30 PM - HIGH PRESSURE WILL WEAKEN OVER THE AREA TONIGHT AS LOW
PRESSURE NEAR THE CAROLINA COAST MOVES NORTH. THE HIGH PRESSURE AS
WELL AS DIURNAL HEATING HAS BEEN ABLE TO SUPPRESS/SLOW DOWN THE
STRATUS DECK TO OUR SOUTH FOR THE MOST PART TODAY...BUT AS WE LOSE
DAYTIME HEATING THIS EVENING THE WARM FRONT WILL SURGE NORTHWARD.
DRIZZLE WILL START SOON AFTER ALONG THE COAST WITH TRUE RAIN
MOVING IN TONIGHT. THE HRRR IS HANDLING THIS SYSTEM BETTER THAN
THE NAM AND SO AM GOING CLOSER TO ITS SOLUTION IN THE FIRST FEW
HOURS. AM NOT EXPECTING MUCH QPF REALLY UNTIL AFTER MIDNIGHT IN NH
AND TOWARDS DAYBREAK IN MAINE. CLOUD COVER WILL KEEP OVERNIGHT
LOWS IN THE MID 50S MOST SPOTS.

&&

.SHORT TERM /7 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
PW VALUES WILL BE AROUND +2 STANDARD DEVIATIONS ABOVE NORMAL
TOMORROW AS LOW PRESSURE PASSES BY TO OUR EAST DRAGGING TROPICAL
MOISTURE WITH IT. A COLD FRONT WILL APPROACH OUR NORTHERN BORDERS
LATE IN THE MORNING AND MOVE THROUGH NORTHERN NEW ENGLAND
THROUGHOUT THE DAY. THIS WILL HELP FOCUS THE MOISTURE AND WE
SHOULD SEE SOME HEAVY RAINFALL AT TIMES WITH URBAN FLOODING AT
TIMES. MODELS ARE DEPICTING MORE MUCAPE THAN SURFACE BASED CAPE
BUT STILL SHOULD HAVE A GOOD CHANCE AT CONVECTION. HIGH
TEMPERATURES WILL RANGE FROM THE LOWER TO MID 60S NORTH TO LOWER
70S SOUTH.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
A MILD AND AT TIMES UNSETTLED PATTERN THROUGH THIS PERIOD. UPPER
LEVEL RIDGE OVER THE REGION WITH A FEW DISTURBANCES MOVING
NORTHEAST IN THE FLOW. WITH INCREASE TEMPS AND MOISTURE THESE
DISTURBANCES SHOULD SET OFF A FEW SHOWERS. THE INCREASE IN TEMPS AND
MOISTURE SHOULD ALSO RESULT IN AREAS OF FOG AND DRIZZLE ESPECIALLY
ALONG COASTAL REGIONS AT NIGHT. LI`S AT OR SLIGHTLY BELOW ZERO WED
AFTERNOON. ISOLATED CONVECTION POSSIBLE. BEST CHANCE OF
THUNDERSTORMS APPEARS TO BE SATURDAY AHEAD OF A COLD FRONT THAT
CROSSES THE AREA.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
SHORT TERM...VFR CONDITIONS WILL DETERIORATE QUICKLY AFTER DARK AS
A WARM FRONT SURGES NORTH AND DRIZZLE...RAIN...AND FOG FOLLOW.
CEILINGS WILL DROP AS LOW AS LIFR. VISIBILITIES WILL BE WORSE
ALONG THE COAST THAN INLAND. IMPROVEMENT TO MVFR OR BETTER IS
LIKELY BY AFTERNOON TUESDAY.

LONG TERM...AREAS OF MVFR DURING THE DAY AND IFR NIGHT AS LOW
LEVEL MOISTURE INCREASES.

&&

.MARINE...
SHORT TERM...SEAS WILL APPROACH SMALL CRAFT CONDITIONS TOMORROW
NIGHT IN THE OUTER WATERS AS A COLD FRONT PUSHES OFFSHORE.

LONG TERM...WIND AND SEAS EXPECTED TO REMAIN BELOW SCA LEVELS.

&&

.FIRE WEATHER...
CLOUDS AND MOISTURE WILL INCREASE TONIGHT AS A WARM FRONT LIFTS
NORTH INTO THE AREA. SCATTERED SHOWERS AND HIGH RELATIVE HUMIDITIES
WILL LAST UNTIL WEDNESDAY. THERE WILL BE A CHANCE OF SHOWERS
WEDNESDAY THROUGH FRIDAY WITH A COLD FRONTAL PASSAGE AND MORE
SUBSTANTIAL RAINS SATURDAY.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...
NEAR TERM...JENSENIUS








AREA FORECAST DISCUSSION

NWS WAKEFIELD VA

 1150 PM EDT MON MAY 21 2012

.SYNOPSIS...
LOW PRESSURE AND UNSETTLED CONDITIONS WILL PERSIST ACROSS THE AREA
THROUGH MID WEEK. HIGH PRESSURE BUILDS INTO THE AREA LATE THIS WEEK
AND INTO THE HOLIDAY WEEKEND.

&&

.NEAR TERM /THROUGH TUESDAY/...
UPDATE TO ADD 30 PERCENT CHC SHOWERS/ISOLATED THUNDER MOST AREAS
WEST OF THE CHESAPEAKE. HRRR AND OTHER HIGH RES MODELS INDICATE
CONVECTION OVERNIGHT IN AN AREA THAT HAS SLIGHTLY NEGATIVE LI/S.
AS OF 03Z...SHOWERS WERE OVER BRUNSWICK COUNTY AND APPROACHING
LUNENBURG AND MECKLENBURG COUNTY FROM THE WEST. LEFT SLGT CHC
SHOWERS ERN PORTIONS WHERE THE ATMPOSPHERE IS RELATIVELY STABLE.

PREVIOUS DISCUSSION...
MOST PCPN HAS WEAKENED / DISSIPATED SINCE SUNSET WITH ONLY A FEW
SHOWERS OVER I95 CORRIDOR NORTH OF RICHMOND. NOW WATCHING BAND OF
SHOWERS / TSTRMS FROM LYH-DAN. TUFF CALL ON JUST HOW FAR EAST THEY
GET NEXT FEW HOURS AS SHORT RANGE MODELS DIFFER A BIT ON HOW LONG
THEY SURVIVE. THUS...HAVE ADDED ISLTD THUNDER TO EXTREME WESTERN
COUNTIES NEXT FEW HOURS FOR ANY CELL THAT DOES MOVE EAST. OTW...ENUF
MOISTURE IN PLACE FOR AT LESAT ISOLATED SHOWERS FOR THE REST OF THE
NIGHT...ESPECIALLY ACROSS WESTERN HALF OF FA DUE TO LINGERING TROF.
ADDED PATCHY FOG ALONG THE EASTERN SHORE. LATER UPDATES MAY HAVE TO
EXPAND THE FOG THREAT TOWARD SUNRISE. WARM AND HUMID. LOWS 60-65.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
UNSETTLED CONDS...NOT DUE TO TS ALBERTO...WILL CONTINUE THRU THE
SHORT TERM PERIOD WITH THE AFOREMENTIONED UPR-LVL TROF STILL IN
PLACE ALONG THE EASTERN SEABOARD. THIS WILL LEAD TO PERIODIC
CHANCES FOR SHOWERS AND STORMS AS MOIST S/SW FLOW CONTINUES. FOR
TUE...SFC TROF WILL BE SITUATED OVR WESTERN PORTIONS OF THE FA
WHERE HIGHEST POPS (50%) WERE PLACED...30-40% ELSEWHERE. TEMPS
CLIMB INTO THE UPR 70S TO LWR 80S UNDER A MSTLY CLDY SKY. RAIN MAY
LINGER INTO TUE NGT...WITH THE BEST CHC AGAIN OVR WESTERN AREAS.
UPR-LVL TROF CUTS OFF FROM THE MEAN FLOW TUE NGT INTO WED AS A
POTENT S/W DIVES DOWN THE TROF BASE. THE CENTER OF THE RESULTING
UPR-LVL LOW WILL CENTER ITSELF NEAR THE MID ATLANTIC WED INTO
THU...WITH CHANCES FOR RAIN EACH DAY. BEST CHANCE FOR RAIN DURING
THE PERIOD WILL BE WED (LIKELY POPS FOR NW QUADRANT OF FA) WITH A
SFC TROF OVR THE MID ATLANTIC...DECENT FORCING ALOFT...AND A VERY
MOIST ATM. SEASONABLE TEMPS CONTINUE WED AND THU...HIGHS STILL IN
THE UPR 70S TO LWR 80S.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE LATEST NUMERICAL GUIDANCE IS SUGGESTING THAT THE PERSISTENT
UPPER LOW MAY LINGER INTO FRIDAY. HOWEVER...AT THIS POINT NOTHING
MORE THAT A SLIGHT CHANCE POP IS NECESSARY. AN UPPER HIGH THEN
BUILDS OVER THE OHIO VALLEY FOR THE MEMORIAL DAY WEEKEND. GIVEN
WHERE THE HIGH SETS UP IT IS POSSIBLE SOME CONVECTION COULD ROUND
THE TOP OF THE RIDGE AND APPROACH THE LOCAL AREA IN MID-LEVEL NNW
FLOW. THE LARGE MAJORITY OF THE TIME IS EXPECTED TO BE DRY AND THERE
IS BASICALLY NO SKILL IN FORECASTING MCS ACTIVITY IN THE MEDIUM
RANGE. TEMPERATURES SHOULD BE ABOVE SEASONAL AVERAGES WITH HIGHS IN
THE MID 80S TO NEAR 90 (SLIGHTLY COOLER ALONG THE COASTS WITH LIGHT
ONSHORE FLOW). LOW TEMPERATURES SHOULD GENERALLY BE IN THE 60S.

&&

.AVIATION /04Z TUESDAY THROUGH SATURDAY/...
WEAK LOW PRESSURE OVER THE REGION WITH MOSTLY LIGHT WINDS FROM THE
E-SE. SOME PERSISTENT SCATTERED SHOWERS CONTINUE MOSTLY OVER THE
NORTHERN PORTIONS OF THE CWA...BUT AN AREA OF SHOWERS AND TSTMS IS
ALSO MOVG THRU THE ROANOKE VALLEY. SOME OF THIS CONVECTION COULD
PSBLY AFFECT WESTERN COUNTIES LATER TONIGHT. BIGGEST CONCERN TONIGHT
IS THE CHANCE OF IFR CONDITIONS DUE TO PLENTY OF LOW LEVEL MOISTURE
WITH IFR CEILINGS DEVELOPING GENERALLY AFTER MIDNIGHT. SOME PATCHY
DENSE FOG WILL LIKELY OCCUR OVER THE EASTERN SHORE BUT FOG WILL
PROBABLY RANGE FROM 1 TO 3 MILES OVER THE REGION DURING THE NIGHT.

VFR CONDITIONS WILL EXPECTED BY MID TO LATE MORNING AS WINDS SHIFT
TO THE S-SW DURING THE OVERNIGHT. MORE SHOWERS AND TSTMS POSSIBLE
FOR TUE AFTN/EVENING AS WEAK INSTABILITY CONTINUES OVER THE REGION.

&&

.MARINE...
THE LATEST SURFACE ANALYSIS SHOWS A RATHER NEBULOUS SURFACE PATTERN
ACROSS THE LOCAL MARNIE AREA AND HENCE WEAK FLOW. THIS GENERAL FLOW
PATTERN SHOULD CONTINUE THROUGH MUCH OF THE WEEK WITH S OR SE FLOW
AOB 10KT. AN AREA OF LOW PRESSURE (NOT TS ALBERTO) PRESENTLY WELL
EAST OF THE NC COAST WILL MOVE NNE ON A TRAJECTORY TOWARD NS THROUGH
TUESDAY. WNA WAVE SHOWS SWELL ASSOCIATED WITH THIS LOW AFFECTING THE
MARINE AREA TUESDAY INTO TUESDAY NIGHT WITH SEAS AOA 5FT GENERALLY
OUT PAST 5-10NM. AN SCA FOR HAZARDOUS SEAS WILL BE RAISED FROM 6AM
TUESDAY TO 6AM WEDNESDAY. OTHERWISE...SEAS SHOULD DROP BELOW SCA FOR
THE REMAINDER OF THE WEEK. UNSETTLED CONDITIONS SHOULD PERSIST MUCH
OF THE WEEK WITH A CHANCE FOR MAINLY AFTERNOON AND EVENING
THUNDERSTORMS.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 6 AM TUESDAY TO 6
     AM EDT WEDNESDAY FOR ANZ650-652-654-656-658.

&&

$$
SYNOPSIS...MAS
NEAR TERM...MPR/LSA
SHORT TERM...MAS
LONG TERM...AJZ
AVIATION...DAP
MARINE...AJZ







AREA FORECAST DISCUSSION

NWS BALTIMORE MD/WASHINGTON DC

 1110 AM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRES OVR NRN NEW ENGLAND CONTINUES TO NOSE DOWN THE ERN
SEABOARD THIS AFTERNOON. THE ARE TWO AREAS OF LOW PRESSURE - A
WEAK SYSTEM WELL E OF VIRGINIA BEACH AND TROPICAL STORM ALBERTO -
OFF THE SOUTH CAROLINA COAST. LOW PRESSURE WILL GRADUALLY LIFT
NORTHEASTWARD MONDAY THROUGH THE MID-ATLANTIC...AS A FRONT MOVES
IN FROM THE WEST FOR TUESDAY AND WEDNESDAY. HIGH PRESSURE SLOWLY
BUILDS IN FOR THE END OF THE WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL REMAIN OVER THE REGION TODAY WHILE LOW PRESSURE
RETROGRADES WESTWARD TOWARD THE NORTH CAROLINA COAST. TROPICAL
STORM ALBERTO REMAINS OFF THE SOUTH CAROLINA COAST...BUT IT WILL
NOT HAVE AN IMPACT ON OUR WEATHER.

MOISTURE WILL WRAP AROUND THE LOW OFF THE NORTH CAROLINA
COAST...CAUSING CLOUDS TO INCREASE ESPECIALLY ACROSS LOWER
SOUTHERN MARYLAND INTO CENTRAL VIRGINIA. ELSEWHERE...PLENTY OF
SUNSHINE IS EXPECTED ALONG WITH DRY CONDITIONS. MAX TEMPS WILL
RANGE FROM THE MID 70S ACROSS LOWER SOUTHERN MARYLAND WHERE MORE
CLOUD COVER IS EXPECTED...TO THE LOWER AND MIDDLE 80S ACROSS MOST
OTHER LOCATIONS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
FOR TNGT MDLS..ESPECIALLY THE NAM...SEEM SOMEWHAT AGGRESSIVE ON
BRINGING RAFL INTO THE RGN IN ASSO W/ THE NRN CSTL LOW (NOT
ALBERTO...WHICH IS RMNG FURTHER S). IT`S INTERESTING TO NOTE THAT
THE HRRR IS SHOWING EVEN NOW A FAIRLY DVLPD SPIRAL BANDING OF PCPN
OFF THE DELMARVA...BUT ON IR STLT IT LOOKS AS IF THERE`S BARELY
EVEN ANY CLD IN ASSO W/ IT. SREF SHOWS THE LOW APRCHG THE CST LN
THIS EVE WHILE WEAKENING ERLY ONSHORE FLOW WL ADVECT SOME MOISTURE
INTO CWA. QUSTN THEN IS HOW FAR W AND HOW MUCH? AND WL ALBERTO
TAKE ENERGY FM THE NRN LOW? I HV CUT BACK ON QPF...AND PUSHED
BACK THE TIMING ABT 6 HRS...PSBLY LGT RA REACHING DC BY 06Z.
WOULDN`T BE SURPRISED IF NO PCPN OCCURS W OF THE BLUE RDG...AND HV
CUT WRN CWA POPS TO LO CHC. BEST CHC FOR RAFL OVRNGT WL LKLY BE LWR
SRN MD.

LOWS IN THE 50S XCPT L60S IN THE CITIES/ALONG THE BAY.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
STACKED LOPRES...MOSTLY UNRELATED TO TROPICAL STORM ALBERTO...WILL CONT WWD
DRIFT INTO MID-ATLC MON. HIGH CHC/LOW LIKELY SHWRS AND ISOLATED
THUNDER FOR MON...WITH DIURNAL PEAK IN CNVCTN. MON NGT PCPN WANES AS
CLOSED LOW OPENS AND IS PULLED NEWD/ABSORBED BY APPROACHING NRN
STREAM ULVL TROF. TROF WILL BE BLOCKED BY STRONG BERMUDA RDGG AND
DRAW STATIONARY TUE...EVOLVING INTO CLOSED LOPRES CNTRD S OF RGN ON
WED. AT SFC...TROF/CDFNT WILL CROSS APLCNS TUE...INDUCING SCT/NUM
SHWRS/TSTMS.  TEMPS SHUD BE REGULATED BY XTNSV CLOUD COVER
MON...SUPPRESSING MAXIMA TO L/M70S. TUE SHUD HAVE SOME BREAKS IN
CLOUDS...ALLOWING TEMPS TO REACH AOA 80F MOST RGN...THUS THE BETTER
TSTM CHCS.  CONFIDENCE IN AFOREMENTIONED IS LOW...AS GUIDANCE IS NOT
IN AGREEMENT AND ALBERTO IS ESPECIALLY NOT WELL HANDLED BY MODELS
ATTM.

WITH M/ULVL LOPRES S/W OF RGN TUE NGT/WED...SFC TROF AXIS WILL
MEANDER THRU CWA AND GRADUALLY WASH OUT...WITH PLENTY MOISTURE IN
PLACE...CHC POPS WARRANTED.  GUIDANCE SUGGESTS THAT ANOTHER NRN
BRANCH TROF WILL BCM DOMINATE ACRS PLAINS THU/FRI...ALLOWING SWLY
FLOW TO ESTABLISH ACRS ERN CONUS. WITH THIS...BERMUDA RIDGE WOULD
BUILD INTO ERN CONUS...TRIGGERING DRIER/WARMER CONDS FOR MID-ATLC
FOR WKS END. STILL...LLVL MOISTURE WILL BE DECENT...SO ISOLATED/SCT
MAINLY DIURNAL CNVCTN CANT BE RULED OUT THRU XTDD FCST.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
VFR CONDS TDA. CLDS XPCTD TO BEGIN TO LOWER TNGT...W/ CIGS DROPPING
INTO THE MVFR RANGE OVERNIGHT. IFR CIGS ARE POSSIBLE AS WELL. LGT
RAIN MAY IMPACT THE TERMINALS OVERNIGHT.

SCT/NUM SHWRS/PSBLY TSTMS WILL IMPACT TERMINALS MON THRU WED.
HIGHLY UNCERTAIN AS TO EXTENT OF PREVAILING FLIGHT
RESTRICTIONS...BUT AT LEAST PERIODS OF SUB-VFR CIGS/VBSYS APPEAR
PLAUSIBLE WITH MOIST ELY FLOW IN PLACE. POPS GRADUALLY DIMINISH FOR
SECOND HALF OF WEEK...AS HIPRES BUILDS IN.

&&

.MARINE...
HIGH PRESSURE WILL REMAIN OVER THE WATERS THIS AFTERNOON...BUT LOW
PRESSURE WILL RETROGRADE INTO NORTH CAROLINA THROUGH TONIGHT. THE
PRESSURE GRADIENT BETWEEN THESE TWO SYSTEMS WILL CAUSE WIND GUSTS
AROUND 20 KNOTS ACROSS THE WATERS THIS AFTERNOON AND EARLY
EVENING. A SMALL CRAFT ADVISORY IS IN EFFECT DURING THIS TIME. THE
SMALL CRAFT ADVISORY CONTINUES THROUGH TONIGHT FOR THE MARYLAND
CHESAPEAKE BAY SOUTH OF SANDY POINT AND THE LOWER TIDAL POTOMAC
RIVER FROM COBB ISLAND TO SMITH POINT.

NELY FLOW CONTS MON/TUE. GUSTS ON MON MAY APPROACH SCA
THRESHOLD...BUT CONFIDENCE TO LOW ATTM FOR EXTENSION OF HEADLINES.
LOPRES RMNS IN VICINITY THRU MIDWK...WITH SCT/NUM SHWRS/TSTMS XPCD.
SFC TROF/CDFNT APPROACHES TUE NGT/WED...WITH HIPRES SLOWLY BUILDING
IN THEREAFTER.

&&

.TIDES/COASTAL FLOODING...
WITH PROLONGED ELY FLOW AND LWRG PRESSURE ACRS CHESAPEAKE BAY...
MINOR COASTAL FLOODING LOOKS LIKELY WITH MON MRNGS HIGH TIDE.
FAVORABLE FLOW WILL CONT MON INTO TUE...SO ADDITIONAL COASTAL
FLOODING OF SENSITIVE LOCATIONS IS POSSIBLE AGAIN DURING HIGH
TIDES THIS PERIOD.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ530-
     531-535-536-538-539.
     SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ532>534-537-
     540>543.

&&

$$
PRODUCTS...LASORSA/WOODY!/SBK







AREA FORECAST DISCUSSION

NWS BALTIMORE MD/WASHINGTON DC

 931 AM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRES OVR NRN NEW ENGLAND CONTINUES TO NOSE DOWN THE ERN
SEABOARD THIS AFTERNOON. THE ARE TWO AREAS OF LOW PRESSURE - A
WEAK SYSTEM WELL E OF VIRGINIA BEACH AND TROPICAL STORM ALBERTO -
OFF THE SOUTH CAROLINA COAST. LOW PRESSURE WILL GRADUALLY LIFT
NORTHEASTWARD MONDAY THROUGH THE MID-ATLANTIC...AS A FRONT MOVES
IN FROM THE WEST FOR TUESDAY AND WEDNESDAY. HIGH PRESSURE SLOWLY
BUILDS IN FOR THE END OF THE WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL REMAIN OVER THE REGION TODAY WHILE LOW PRESSURE
RETROGRADES WESTWARD TOWARD THE NORTH CAROLINA COAST. TROPICAL
STORM ALBERTO REMAINS OFF THE SOUTH CAROLINA COAST...BUT IT WILL
NOT HAVE AN IMPACT ON OUR WEATHER.

MOISTURE WILL WRAP AROUND THE LOW OFF THE NORTH CAROLINA
COAST...CAUSING CLOUDS TO INCREASE ESPECIALLY ACROSS LOWER
SOUTHERN MARYLAND INTO CENTRAL VIRGINIA. ELSEWHERE...PLENTY OF
SUNSHINE IS EXPECTED ALONG WITH DRY CONDITIONS. MAX TEMPS WILL
RANGE FROM THE MID 70S ACROSS LOWER SOUTHERN MARYLAND WHERE MORE
CLOUD COVER IS EXPECTED...TO THE LOWER AND MIDDLE 80S ACROSS MOST
OTHER LOCATIONS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
FOR TNGT MDLS..ESPECIALLY THE NAM...SEEM SOMEWHAT AGGRESSIVE ON
BRINGING RAFL INTO THE RGN IN ASSO W/ THE NRN CSTL LOW (NOT
ALBERTO...WHICH IS RMNG FURTHER S). IT`S INTERESTING TO NOTE THAT
THE HRRR IS SHOWING EVEN NOW A FAIRLY DVLPD SPIRAL BANDING OF PCPN
OFF THE DELMARVA...BUT ON IR STLT IT LOOKS AS IF THERE`S BARELY
EVEN ANY CLD IN ASSO W/ IT. SREF SHOWS THE LOW APRCHG THE CST LN
THIS EVE WHILE WEAKENING ERLY ONSHORE FLOW WL ADVECT SOME MOISTURE
INTO CWA. QUSTN THEN IS HOW FAR W AND HOW MUCH? AND WL ALBERTO
TAKE ENERGY FM THE NRN LOW? I HV CUT BACK ON QPF...AND PUSHED
BACK THE TIMING ABT 6 HRS...PSBLY LGT RA REACHING DC BY 06Z.
WOULDN`T BE SURPRISED IF NO PCPN OCCURS W OF THE BLUE RDG...AND HV
CUT WRN CWA POPS TO LO CHC. BEST CHC FOR RAFL OVRNGT WL LKLY BE LWR
SRN MD.

LOWS IN THE 50S XCPT L60S IN THE CITIES/ALONG THE BAY.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
STACKED LOPRES...MOSTLY UNRELATED TO TROPICAL STORM ALBERTO...WILL CONT WWD
DRIFT INTO MID-ATLC MON. HIGH CHC/LOW LIKELY SHWRS AND ISOLATED
THUNDER FOR MON...WITH DIURNAL PEAK IN CNVCTN. MON NGT PCPN WANES AS
CLOSED LOW OPENS AND IS PULLED NEWD/ABSORBED BY APPROACHING NRN
STREAM ULVL TROF. TROF WILL BE BLOCKED BY STRONG BERMUDA RDGG AND
DRAW STATIONARY TUE...EVOLVING INTO CLOSED LOPRES CNTRD S OF RGN ON
WED. AT SFC...TROF/CDFNT WILL CROSS APLCNS TUE...INDUCING SCT/NUM
SHWRS/TSTMS.  TEMPS SHUD BE REGULATED BY XTNSV CLOUD COVER
MON...SUPPRESSING MAXIMA TO L/M70S. TUE SHUD HAVE SOME BREAKS IN
CLOUDS...ALLOWING TEMPS TO REACH AOA 80F MOST RGN...THUS THE BETTER
TSTM CHCS.  CONFIDENCE IN AFOREMENTIONED IS LOW...AS GUIDANCE IS NOT
IN AGREEMENT AND ALBERTO IS ESPECIALLY NOT WELL HANDLED BY MODELS
ATTM.

WITH M/ULVL LOPRES S/W OF RGN TUE NGT/WED...SFC TROF AXIS WILL
MEANDER THRU CWA AND GRADUALLY WASH OUT...WITH PLENTY MOISTURE IN
PLACE...CHC POPS WARRANTED.  GUIDANCE SUGGESTS THAT ANOTHER NRN
BRANCH TROF WILL BCM DOMINATE ACRS PLAINS THU/FRI...ALLOWING SWLY
FLOW TO ESTABLISH ACRS ERN CONUS. WITH THIS...BERMUDA RIDGE WOULD
BUILD INTO ERN CONUS...TRIGGERING DRIER/WARMER CONDS FOR MID-ATLC
FOR WKS END. STILL...LLVL MOISTURE WILL BE DECENT...SO ISOLATED/SCT
MAINLY DIURNAL CNVCTN CANT BE RULED OUT THRU XTDD FCST.

&&

.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
VFR CONDS TDA. CLDS XPCTD TO BEGIN TO LOWER TNGT...W/ CIGS DROPPING
INTO THE MVFR RANGE OVERNIGHT. IFR CIGS ARE POSSIBLE AS WELL. LGT
RAIN MAY IMPACT THE TERMINALS OVERNIGHT.

SCT/NUM SHWRS/PSBLY TSTMS WILL IMPACT TERMINALS MON THRU WED.
HIGHLY UNCERTAIN AS TO EXTENT OF PREVAILING FLIGHT
RESTRICTIONS...BUT AT LEAST PERIODS OF SUB-VFR CIGS/VBSYS APPEAR
PLAUSIBLE WITH MOIST ELY FLOW IN PLACE. POPS GRADUALLY DIMINISH FOR
SECOND HALF OF WEEK...AS HIPRES BUILDS IN.

&&

.MARINE...
HIGH PRESSURE WILL REMAIN OVER THE WATERS THIS AFTERNOON...BUT LOW
PRESSURE WILL RETROGRADE ONTO THE NORTH CAROLINA COAST INTO
TONIGHT. THE PRESSURE GRADIENT BETWEEN THESE TWO SYSTEMS WILL
CAUSE WIND GUSTS AROUND 20 KNOTS ACROSS THE MIDDLE PORTION OF THE
BAY AND LOWER TIDAL POTOMAC RIVER. A SMALL CRAFT ADVISORY IS IN
EFFECT FOR THESE AREAS THROUGH TONIGHT.

NELY FLOW CONTS MON/TUE. GUSTS ON MON MAY APPROACH SCA
THRESHOLD...BUT CONFIDENCE TO LOW ATTM FOR EXTENSION OF HEADLINES.
LOPRES RMNS IN VICINITY THRU MIDWK...WITH SCT/NUM SHWRS/TSTMS XPCD.
SFC TROF/CDFNT APPROACHES TUE NGT/WED...WITH HIPRES SLOWLY BUILDING
IN THEREAFTER.

&&

.TIDES/COASTAL FLOODING...
WITH PROLONGED ELY FLOW AND LWRG PRESSURE ACRS CHESAPEAKE BAY...
MINOR COASTAL FLOODING LOOKS LIKELY WITH MON MRNGS HIGH TIDE.
FAVORABLE FLOW WILL CONT MON INTO TUE...SO ADDITIONAL COASTAL
FLOODING OF SENSITIVE LOCATIONS IS POSSIBLE AGAIN DURING HIGH
TIDES THIS PERIOD.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ532>534-537-
     540>543.

&&

$$
PRODUCTS...LASORSA/WOODY!/SBK







AREA FORECAST DISCUSSION

NWS BALTIMORE MD/WASHINGTON DC

 329 AM EDT SUN MAY 20 2012

.SYNOPSIS...

HIGH PRES OVR NRN NEW ENGLAND CONTINUES TO NOSE DOWN THE ERN
SEABOARD TDA. THE ARE TWO AREAS OF LOW PRESSURE - A WEAK SYSTEM
WELL E OF VIRGINIA BEACH AND TROPICAL STORM ALBERTO - OFF THE
SOUTH CAROLINA COAST. LOW PRESSURE WILL GRADUALLY LIFT
NORTHEASTWARD MONDAY THROUGH THE MID-ATLANTIC...AS A FRONT MOVES
IN FROM THE WEST FOR TUESDAY AND WEDNESDAY. HIGH PRESSURE SLOWLY
BUILDS IN FOR THE END OF THE WEEK.

&&

.NEAR TERM /TODAY/...

WX SURE HAS BEEN NICE FOR THE PAST SVRL DAYS...40S DWPTS HV MADE
THINGS VERY COMFORTABLE. TDA SHOULD BE ANOTHER FINE DAY OF
WX...ALTHO DWPTS HV CREPT BACK INTO THE 50S. HIGH PRES WHICH HAS
BEEN RESPONSIBLE FOR THIS HAS DONE A SLOW CRAWL OVR THE PAST 48
HRS FM NY STATE TO CT AND NOW TO NRN NH. TDA A WK AREA OF LOW
PRES HAS FORMED E OF ORF...AND IN A REAL RARITY TS ALBERTO HAS
DVLPD OFF THE S CAROLINA CST. FOR TDA ALL THESE SHOULD DO FOR MID
ATLC IS CONT TO PRODUCE CI. YDA TEMPS REACHED LM80S ACROSS MUCH OF
THE AREA. LK LAST NGT WE`LL BE BEGINNING THE DAY FM A HIGHER TEMP
STARTING PT THAN DURG THE LAST DAYS OF THE WORKWEEK...SO WE CAN
XPCT TO SEE LM80S AGN THIS AFTN.

&&

.SHORT TERM /TONIGHT/...

FOR TNGT MDLS..ESPECIALLY THE NAM...SEEM SOMEWHAT AGGRESSIVE ON
BRINGING RAFL INTO THE RGN IN ASSO W/ THE NRN CSTL LOW (NOT
ALBERTO...WHICH IS RMNG FURTHER S). IT`S INTERESTING TO NOTE THAT
THE HRRR IS SHOWING EVEN NOW A FAIRLY DVLPD SPIRAL BANDING OF PCPN
OFF THE DELMARVA...BUT ON IR STLT IT LOOKS AS IF THERE`S BARELY
EVEN ANY CLD IN ASSO W/ IT. SREF SHOWS THE LOW APRCHG THE CST LN
THIS EVE WHILE WEAKENING ERLY ONSHORE FLOW WL ADVECT SOME MOISTURE
INTO CWA. QUSTN THEN IS HOW FAR W AND HOW MUCH? AND WL ALBERTO
TAKE ENERGY FM THE NRN LOW? I HV CUT BACK ON QPF...AND PUSHED
BACK THE TIMING ABT 6 HRS...PSBLY LGT RA REACHING DC BY 06Z.
WOULDN`T BE SURPRISED IF NO PCPN OCCURS W OF THE BLUE RDG...AND HV
CUT WRN CWA POPS TO LO CHC. BEST CHC FOR RAFL OVRNGT WL LKLY BE LWR
SRN MD.

LOWS IN THE 50S XCPT L60S IN THE CITIES/ALONG THE BAY.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...

STACKED LOPRES...MOSTLY UNRELATED TO TROPICAL STORM ALBERTO...WILL CONT WWD
DRIFT INTO MID-ATLC MON. HIGH CHC/LOW LIKELY SHWRS AND ISOLATED
THUNDER FOR MON...WITH DIURNAL PEAK IN CNVCTN. MON NGT PCPN WANES AS
CLOSED LOW OPENS AND IS PULLED NEWD/ABSORBED BY APPROACHING NRN
STREAM ULVL TROF. TROF WILL BE BLOCKED BY STRONG BERMUDA RDGG AND
DRAW STATIONARY TUE...EVOLVING INTO CLOSED LOPRES CNTRD S OF RGN ON
WED. AT SFC...TROF/CDFNT WILL CROSS APLCNS TUE...INDUCING SCT/NUM
SHWRS/TSTMS.  TEMPS SHUD BE REGULATED BY XTNSV CLOUD COVER
MON...SUPPRESSING MAXIMA TO L/M70S. TUE SHUD HAVE SOME BREAKS IN
CLOUDS...ALLOWING TEMPS TO REACH AOA 80F MOST RGN...THUS THE BETTER
TSTM CHCS.  CONFIDENCE IN AFOREMENTIONED IS LOW...AS GUIDANCE IS NOT
IN AGREEMENT AND ALBERTO IS ESPECIALLY NOT WELL HANDLED BY MODELS
ATTM.

WITH M/ULVL LOPRES S/W OF RGN TUE NGT/WED...SFC TROF AXIS WILL
MEANDER THRU CWA AND GRADUALLY WASH OUT...WITH PLENTY MOISTURE IN
PLACE...CHC POPS WARRANTED.  GUIDANCE SUGGESTS THAT ANOTHER NRN
BRANCH TROF WILL BCM DOMINATE ACRS PLAINS THU/FRI...ALLOWING SWLY
FLOW TO ESTABLISH ACRS ERN CONUS. WITH THIS...BERMUDA RIDGE WOULD
BUILD INTO ERN CONUS...TRIGGERING DRIER/WARMER CONDS FOR MID-ATLC
FOR WKS END. STILL...LLVL MOISTURE WILL BE DECENT...SO ISOLATED/SCT
MAINLY DIURNAL CNVCTN CANT BE RULED OUT THRU XTDD FCST.

&&

.AVIATION /07Z SUNDAY THROUGH THURSDAY/...

VFR CONDS TDA. CLDS XPCTD TO BEGIN TO LOWER TNGT...W/ CIGS PSBLY
DROPPING INTO THE MVFR RANGE LATE THIS EVE. LGT RA PSBL OVRNGT BUT
NOT XPCTD TO CAUSE A REDUCTION TO VSBY.

SCT/NUM SHWRS/PSBLY TSTMS WILL IMPACT TERMINALS MON THRU WED.
HIGHLY UNCERTAIN AS TO EXTENT OF PREVAILING FLIGHT
RESTRICTIONS...BUT AT LEAST PERIODS OF SUB-VFR CIGS/VBSYS APPEAR
PLAUSIBLE WITH MOIST ELY FLOW IN PLACE. POPS GRADUALLY DIMINISH FOR
SECOND HALF OF WEEK...AS HIPRES BUILDS IN.

&&

.MARINE...

WINDS HV BEEN BLO SCA LVLS IN EVEN OUR LWR PTMC/BAY..SO HV PUSHED
THE START TIME OF THE SCA TO 8 AM. AS OFFSHORE LOW MOVES CLOSER TO
THE CST XPCT TO SEE MORE 20 KT NRLY GUSTS TDA FM S CHES BAY OF
SANDY PT AND TDL PTMC E OF COBB ISLAND.

NELY FLOW CONTS MON/TUE. GUSTS ON MON MAY APPROACH SCA
THRESHOLD...BUT CONFIDENCE TO LOW ATTM FOR EXTENSION OF HEADLINES.
LOPRES RMNS IN VICINITY THRU MIDWK...WITH SCT/NUM SHWRS/TSTMS XPCD.
SFC TROF/CDFNT APPROACHES TUE NGT/WED...WITH HIPRES SLOWLY BUILDING
IN THEREAFTER.

&&

.TIDES/COASTAL FLOODING...

WITH PROLONGED ELY FLOW AND LWRG PRESSURE ACRS CHESAPEAKE BAY...
MINOR COASTAL FLOODING LOOKS LIKELY WITH MON MRNGS HIGH TIDE.
FAVORABLE FLOW WILL CONT MON INTO TUE...SO ADDITIONAL COASTAL
FLOODING OF SENSITIVE LOCATIONS IS POSSIBLE AGAIN DURING HIGH
TIDES THIS PERIOD.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 6 AM EDT MONDAY
     FOR ANZ532>534-537-540>543.

&&

$$
PRODUCTS...WOODY!/SBK








AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

 128 PM CDT SUN MAY 20 2012

.UPDATE...

UPDATED FOR THE 18Z AVIATION DISCUSSION BELOW.

.DISCUSSION...
/ISSUED 423 AM CDT SUN MAY 20 2012/

RAP H5 ANALYSIS ALONG WITH WATER VAPOR IMAGERY SHOWING NEG TILTED
AND FAIRLY STRONG SHORTWAVE MOVING INTO SRN MN THIS MORNING...THAT
IS FLANKED BY FAIRLY ROBUST RIDGING OVER THE ERN GREAT LAKES AND A
WEAK RIDGE NOW MOVING ACROSS THE ROCKIES. A STRONG UPPER JET AND
DEEP UPPER LOW CAN BE SEEN ACROSS THE NRN PAC THAT IS ON ITS WAY
TOWARD WRN CANADA. AT THE SFC...A COUPLE OF COLD FRONTS WERE
ANALYZED ACROSS THE AREA THIS MORNING. THE MAIN COLD FRONT AT 330
AM STRETCHED FROM NEAR ALBERT LEA UP TO THE ASHLAND...WI
AREA...WITH A SECONDARY COLD FRONT SPLAYED OUT ACROSS MN FROM NEAR
DULUTH TO FARGO. ALONG THE PRIMARY FRONT...THERE IS A SFC
CIRCULATION NEAR ROCHESTER. TO THE WEST OF ALL OF THIS...A
SPRAWLING AREA OF HIGH PRESSURE SITS ON OUR DOORSTEP ACROSS THE
NORTHERN PLAINS.

UPPER LOW MOVING INTO SRN MN WILL BE OVER THE U.P. OF MICH BY
TONIGHT AS IT SLOWLY DE-AMPLIFIES AS IT RUNS INTO THE ERN RIDGE.
UPPER RIDGE CURRENTLY OVER THE ROCKIES WILL SLIP ACROSS THE AREA
MON/TUE AS THE UPPER LOW CURRENTLY IN THE NRN PAC MOVES TO THE BC
COAST AS SIGNIFICANT TROUGH SETS UP OVER THE NRN ROCKIES. THIS
GENERAL TROUGH/RIDGE PATTERN WILL BASICALLY REMAIN IN PLACE INTO
THE HOLIDAY WEEKEND...THOUGH BECOME CONSIDERABLY MORE
AMPLIFIED...WITH H5 HEIGHTS IN SUBTROPICAL RIDGE OVER THE OHIO
VALLEY PEGGED TO RISE ABOVE 590 DM.

AT THE SFC...COLD FRONT LOOKS TO CLEAR THE ERN MPX CWA AROUND
18Z...WITH THE SFC LOW TRACKING FROM RST UP THROUGH EAU. HIGH
PRESSURE WILL QUICKLY MOVE ACROSS THE AREA MONDAY...WITH A STRONG
LEE SIDE LOW EXPECTED TO DEVELOP OVER WRN NODAK TUESDAY. FRONTAL
FEATURE WITH THIS LOW STILL ON TRACK TO MOVE INTO WRN MN
WED...THEN STALL OUT THU NIGHT AS IT RUNS INTO THE AMPLIFYING
RIDGE TO THE SOUTH AND EAST. THE GFS/ECMWF SHOW THIS FRONT HANGING
OUT NEAR THE MPX AREA AS A WARM/STATIONARY FRONT THROUGH THE
WEEKEND...WITH NO STRONG KICKER SYSTEM INDICATED UNTIL MEMORIAL
DAY AT THE EARLIEST.

FOR TODAY THE MAIN ISSUES REVOLVE AROUND MOVING POPS OUT OF THE
AREA...HOW MUCH IF AT ALL DO TEMPS WARM UP OUTSIDE OF WRN MN...AND
HOW STRONG WILL THE WINDS BE THIS MORNING. FOR POPS...THE RAP
SHOWS THE DEFORMATION BAND OF PRECIP FOLLOWING JUST W/NW OF THE
SFC LOW. USED A BLEND OF THE HRRR/GEM/NAM TO CRAWL PRECIP ACROSS
THE AREA...WITH MOST PRECIP OUT OF MN BY 18Z...WITH RAIN CLEARING
EAU/LADYSMITH AROUND 21Z. FOR TEMPS...CONTINUED NORTH
WINDS...COMBINED WITH RAINFALL BEHIND THE COLD FRONT HAS STEADILY
BEAT TEMPERATURES BACK INTO THE 50S ACROSS THE MN PORTION OF THE
CWA...WITH 40S NOT TOO FAR AWAY. GIVEN PREFERENCE FOR HANDLING OF
PRECIP THIS MORNING BY THE GEM/NAM...USED THESE MODELS FOR HIGHS
TODAY...WHICH ENDED UP BEING FAIRLY AGGRESSIVE ON THE COLD SIDE OF
THINGS...WITH HIGHS ONLY AROUND 60 UP THE I-35 CORRIDOR. THIS COULD
BUST IN A BIG WAY IF WE CLEAR OUT FOR A COUPLE OF HOURS THIS
AFTERNOON...BUT CLEARING DOES NOT LOOK TO GET TO THE 35 CORRIDOR
SOON ENOUGH TO ALLOW MUCH OF AN IMPROVEMENT IN TEMPS TODAY. FOR
WRN WI...HIGHS WILL BE ACHIEVED BY 18Z...WITH FALLING TEMPS
EXPECTED THROUGH THE AFTERNOON. AS FOR WINDS...HAVE SEEN SOME 40
TO 50 MPH WINDS GUSTS OVERNIGHT IN CENTRAL MN. THOUGH NOT
EXPECTING ANYTHING LIKE THAT TODAY...THE HRRR DOES SHOW A FAIRLY
TIGHT PRESSURE GRADIENT DEVELOPING ON THE WRN EDGE OF THE SFC LOW
WORKING THROUGH SE MN RIGHT NOW. THE HRRR HAS BEEN DOING PRETTY
GOOD AT PICKING UP THE STRONGER WINDS THROUGH THE NIGHT...SO
LEANED HEAVILY ON IT FOR WINDS THIS MORNING...WITH SOME 20-25 MPH
SUSTAINED NORTH WINDS ACROSS ERN MN THROUGH THE MORNING.

TONIGHT...SFC RIDGE OVER THE HIGHS PLAINS WILL MOVE
OVERHEAD...WITH CLEAR SKIES...CALM WINDS...AND A LOW STARTING
POINT WITH TEMPS THIS EVENING ALL CONSPIRING FOR A RATHER COOL
MORNING ON MONDAY...WITH 40S EXPECTED AND A FEW LOWS IN THE 30S
NOT OUT OF THE QUESTION ACROSS CENTRAL MN. MONDAY WILL BE VERY
PLEASANT...WITH ONLY REAL QUESTION BEING HOW LOW DO DEWPS GO IN
THE AFTERNOON. SOUNDINGS CERTAINLY INDICATE STRONG POTENTIAL FOR
SOME GOOD MIXING OF DRIER AIR TO THE SFC AND FAVORED DEWPS MONDAY
TOWARD THE MUCH DRIER MET.

FOR MONDAY NIGHT...STRONG WAA WILL BE COMING IN ALOFT OUT AHEAD OF
THE SYSTEM DEVELOPING OVER THE WRN DAKOTAS. 20.00 GFS GENERATES
SOME ELEVATED THUNDERSTORMS IN WRN MN MON NIGHT IN THIS WAA...BUT
QUICK LOOK AT SOUNDINGS AND RH HEIGHT PROFILES SHOWS ATMO BELOW
10K FT BEING QUITE DRY...SO KEPT THE FORECAST DRY WITH THE
EXPECTATION OF ANOTHER GOOD ROUND OF ACCUS/VIRGA BREAKING OUT. OF
COURSE WITH THAT WAA...A SIGNIFICANT WARM TONGUE AT H85 IS
FORECAST BY ALL MODELS TO COME INTO WRN MN...WITH TEMPS BETWEEN 16
AND 18C NOTED. LAST WEEK THIS RESULTED IN HIGHS IN THE 90S AND
THERE IS GUIDANCE SHOWING PLACES LIKE MADISON GETTING BACK INTO
THE 90S TUESDAY. HOWEVER...THE WARM FRONT SHOULD STAY OFF TO OUR
SW...SO NOT FEELING CONFIDENT IN 90S OCCURRING AGAIN...BUT DID BUMP
WRN MN UP INTO THE MID/UPPER 80S.

AFTER THAT...WHAT LOOKS LIKE A GOOD BET IS ANOTHER ROUND OF
SHOWERS AND THUNDERSTORMS WED AFTERNOON INTO THU AS ANOTHER COLD
FRONT MOVES IN. THERE ARE TIMING DIFFERENCES WITH THIS
FRONT...WITH THE GFS SHOWING MORE WED/WED NIGHT WHILE THE ECMWF IS
MORE WED NIGHT/THU. EITHER WAY...DOES LOOK LIKE ANOTHER GOOD SHOT
AT SOME HEALTHY RAINS AS THE FRONT STALLS OUT OVER/NEAR MN
THURSDAY. BEYOND THURSDAY...CONFIDENCE DECREASES QUITE A BIT ON
THE FORECAST AS THE GFS/ECMWF DIFFER ON WHERE TO PLACE THE
STATIONARY/WARM FRONT FRIDAY RIGHT THROUGH MEMORIAL DAY. GIVEN THE
STRENGTHENING RIDGE TO THE SOUTH AND EAST OVER NEXT WEEKEND...THE
FRONT COULD CERTAINLY BE A BREEDING GROUND FOR SEVERAL ROUNDS OF
THUNDERSTORMS AS MOISTURE RIDES UP OVER IT. IF WE EVER END UP ON
THE SOUTH END OF THE FRONT NEXT WEEKEND...RECORD TEMPS CERTAINLY
LOOK LIKE A POSSIBILITY AS H85 TEMPS ARE PROGGED TO GET UP INTO
THE MID/UPPER 20S C OVER THE CENTRAL PLAINS. THE 20.00
ECMWF/GFS...BOTH SHOW THIS FRONT WELL SOUTH OF THE AREA
FRIDAY...WITH IT SLOWLY LIFTING TO NORTH OF THE MPX AREA BY
SUNDAY.

&&

.AVIATION.../18Z TAF ISSUANCE/

IFR/MVFR CEILINGS WILL SLOWLY WALK ACROSS MN/WI THIS AFTERNOON AND
EARLY EVENING. SATELLITE TRENDS SHOW VFR CONDITIONS AND FILTERED
SUNSHINE IN WESTERN MN. THIS IS TRENDING EAST...SO MUCH OF MN WILL
BE VFR BY 00Z. A COMBINATION OF LIGHT RAIN/DRIZZLE IS
CONTRIBUTING TO THE REDUCED VIS...WHICH IS ABOUT HALF WAY ACROSS
MN. DRIER AIR IS MOVING IN BEHIND THE FRONT...BUT ITS VERY SLOW
AND AS A RESULT...WONDERING IF PATCHY FOG WON`T BE AN ISSUE EARLY
FRIDAY MORNING IN EASTERN MN AND WEST CENTRAL WI.

KMSP...PROBABLY SHOULD HAVE STARTED THE TAF OUT WITH AN HOUR OF
IFR...AND TRANSITIONED BACK TO MVFR. THE CEILINGS HAVE SHOWN SOME
VARIABILITY...WITH BASES RANGING FROM 600-1300FT OVER THE LAST FEW
HOURS. STARTED THE TAF REALLY WITH WHAT`S EXPECTED SHORTLY. THINK
THE WORST OF THE CIGS/VIS WILL BE FINISHED BY THE LATE AFTERNOON.
VFR THEREAFTER ALONG WITH DECREASING WIND.

OUTLOOK...
MON-TUE...VFR.
WED-WED...MVFR POSSIBLE WITH SHOWERS AND THUNDERSTORMS.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&

$$

MPG/CLF







AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

 704 AM CDT SUN MAY 20 2012

.UPDATE...

UPDATED FOR AVIATION DISCUSSION BELOW.

&&

.DISCUSSION...
/ISSUED 423 AM CDT SUN MAY 20 2012/

RAP H5 ANALYSIS ALONG WITH WATER VAPOR IMAGERY SHOWING NEG TILTED
AND FAIRLY STRONG SHORTWAVE MOVING INTO SRN MN THIS MORNING...THAT
IS FLANKED BY FAIRLY ROBUST RIDGING OVER THE ERN GREAT LAKES AND A
WEAK RIDGE NOW MOVING ACROSS THE ROCKIES. A STRONG UPPER JET AND
DEEP UPPER LOW CAN BE SEEN ACROSS THE NRN PAC THAT IS ON ITS WAY
TOWARD WRN CANADA. AT THE SFC...A COUPLE OF COLD FRONTS WERE
ANALYZED ACROSS THE AREA THIS MORNING. THE MAIN COLD FRONT AT 330
AM STRETCHED FROM NEAR ALBERT LEA UP TO THE ASHLAND...WI
AREA...WITH A SECONDARY COLD FRONT SPLAYED OUT ACROSS MN FROM NEAR
DULUTH TO FARGO. ALONG THE PRIMARY FRONT...THERE IS A SFC
CIRCULATION NEAR ROCHESTER. TO THE WEST OF ALL OF THIS...A
SPRAWLING AREA OF HIGH PRESSURE SITS ON OUR DOORSTEP ACROSS THE
NORTHERN PLAINS.

UPPER LOW MOVING INTO SRN MN WILL BE OVER THE U.P. OF MICH BY
TONIGHT AS IT SLOWLY DE-AMPLIFIES AS IT RUNS INTO THE ERN RIDGE.
UPPER RIDGE CURRENTLY OVER THE ROCKIES WILL SLIP ACROSS THE AREA
MON/TUE AS THE UPPER LOW CURRENTLY IN THE NRN PAC MOVES TO THE BC
COAST AS SIGNIFICANT TROUGH SETS UP OVER THE NRN ROCKIES. THIS
GENERAL TROUGH/RIDGE PATTERN WILL BASICALLY REMAIN IN PLACE INTO
THE HOLIDAY WEEKEND...THOUGH BECOME CONSIDERABLY MORE
AMPLIFIED...WITH H5 HEIGHTS IN SUBTROPICAL RIDGE OVER THE OHIO
VALLEY PEGGED TO RISE ABOVE 590 DM.

AT THE SFC...COLD FRONT LOOKS TO CLEAR THE ERN MPX CWA AROUND
18Z...WITH THE SFC LOW TRACKING FROM RST UP THROUGH EAU. HIGH
PRESSURE WILL QUICKLY MOVE ACROSS THE AREA MONDAY...WITH A STRONG
LEE SIDE LOW EXPECTED TO DEVELOP OVER WRN NODAK TUESDAY. FRONTAL
FEATURE WITH THIS LOW STILL ON TRACK TO MOVE INTO WRN MN
WED...THEN STALL OUT THU NIGHT AS IT RUNS INTO THE AMPLIFYING
RIDGE TO THE SOUTH AND EAST. THE GFS/ECMWF SHOW THIS FRONT HANGING
OUT NEAR THE MPX AREA AS A WARM/STATIONARY FRONT THROUGH THE
WEEKEND...WITH NO STRONG KICKER SYSTEM INDICATED UNTIL MEMORIAL
DAY AT THE EARLIEST.

FOR TODAY THE MAIN ISSUES REVOLVE AROUND MOVING POPS OUT OF THE
AREA...HOW MUCH IF AT ALL DO TEMPS WARM UP OUTSIDE OF WRN MN...AND
HOW STRONG WILL THE WINDS BE THIS MORNING. FOR POPS...THE RAP
SHOWS THE DEFORMATION BAND OF PRECIP FOLLOWING JUST W/NW OF THE
SFC LOW. USED A BLEND OF THE HRRR/GEM/NAM TO CRAWL PRECIP ACROSS
THE AREA...WITH MOST PRECIP OUT OF MN BY 18Z...WITH RAIN CLEARING
EAU/LADYSMITH AROUND 21Z. FOR TEMPS...CONTINUED NORTH
WINDS...COMBINED WITH RAINFALL BEHIND THE COLD FRONT HAS STEADILY
BEAT TEMPERATURES BACK INTO THE 50S ACROSS THE MN PORTION OF THE
CWA...WITH 40S NOT TOO FAR AWAY. GIVEN PREFERENCE FOR HANDLING OF
PRECIP THIS MORNING BY THE GEM/NAM...USED THESE MODELS FOR HIGHS
TODAY...WHICH ENDED UP BEING FAIRLY AGGRESSIVE ON THE COLD SIDE OF
THINGS...WITH HIGHS ONLY AROUND 60 UP THE I-35 CORRIDOR. THIS COULD
BUST IN A BIG WAY IF WE CLEAR OUT FOR A COUPLE OF HOURS THIS
AFTERNOON...BUT CLEARING DOES NOT LOOK TO GET TO THE 35 CORRIDOR
SOON ENOUGH TO ALLOW MUCH OF AN IMPROVEMENT IN TEMPS TODAY. FOR
WRN WI...HIGHS WILL BE ACHIEVED BY 18Z...WITH FALLING TEMPS
EXPECTED THROUGH THE AFTERNOON. AS FOR WINDS...HAVE SEEN SOME 40
TO 50 MPH WINDS GUSTS OVERNIGHT IN CENTRAL MN. THOUGH NOT
EXPECTING ANYTHING LIKE THAT TODAY...THE HRRR DOES SHOW A FAIRLY
TIGHT PRESSURE GRADIENT DEVELOPING ON THE WRN EDGE OF THE SFC LOW
WORKING THROUGH SE MN RIGHT NOW. THE HRRR HAS BEEN DOING PRETTY
GOOD AT PICKING UP THE STRONGER WINDS THROUGH THE NIGHT...SO
LEANED HEAVILY ON IT FOR WINDS THIS MORNING...WITH SOME 20-25 MPH
SUSTAINED NORTH WINDS ACROSS ERN MN THROUGH THE MORNING.

TONIGHT...SFC RIDGE OVER THE HIGHS PLAINS WILL MOVE
OVERHEAD...WITH CLEAR SKIES...CALM WINDS...AND A LOW STARTING
POINT WITH TEMPS THIS EVENING ALL CONSPIRING FOR A RATHER COOL
MORNING ON MONDAY...WITH 40S EXPECTED AND A FEW LOWS IN THE 30S
NOT OUT OF THE QUESTION ACROSS CENTRAL MN. MONDAY WILL BE VERY
PLEASANT...WITH ONLY REAL QUESTION BEING HOW LOW DO DEWPS GO IN
THE AFTERNOON. SOUNDINGS CERTAINLY INDICATE STRONG POTENTIAL FOR
SOME GOOD MIXING OF DRIER AIR TO THE SFC AND FAVORED DEWPS MONDAY
TOWARD THE MUCH DRIER MET.

FOR MONDAY NIGHT...STRONG WAA WILL BE COMING IN ALOFT OUT AHEAD OF
THE SYSTEM DEVELOPING OVER THE WRN DAKOTAS. 20.00 GFS GENERATES
SOME ELEVATED THUNDERSTORMS IN WRN MN MON NIGHT IN THIS WAA...BUT
QUICK LOOK AT SOUNDINGS AND RH HEIGHT PROFILES SHOWS ATMO BELOW
10K FT BEING QUITE DRY...SO KEPT THE FORECAST DRY WITH THE
EXPECTATION OF ANOTHER GOOD ROUND OF ACCUS/VIRGA BREAKING OUT. OF
COURSE WITH THAT WAA...A SIGNIFICANT WARM TONGUE AT H85 IS
FORECAST BY ALL MODELS TO COME INTO WRN MN...WITH TEMPS BETWEEN 16
AND 18C NOTED. LAST WEEK THIS RESULTED IN HIGHS IN THE 90S AND
THERE IS GUIDANCE SHOWING PLACES LIKE MADISON GETTING BACK INTO
THE 90S TUESDAY. HOWEVER...THE WARM FRONT SHOULD STAY OFF TO OUR
SW...SO NOT FEELING CONFIDENT IN 90S OCCURRING AGAIN...BUT DID BUMP
WRN MN UP INTO THE MID/UPPER 80S.

AFTER THAT...WHAT LOOKS LIKE A GOOD BET IS ANOTHER ROUND OF
SHOWERS AND THUNDERSTORMS WED AFTERNOON INTO THU AS ANOTHER COLD
FRONT MOVES IN. THERE ARE TIMING DIFFERENCES WITH THIS
FRONT...WITH THE GFS SHOWING MORE WED/WED NIGHT WHILE THE ECMWF IS
MORE WED NIGHT/THU. EITHER WAY...DOES LOOK LIKE ANOTHER GOOD SHOT
AT SOME HEALTHY RAINS AS THE FRONT STALLS OUT OVER/NEAR MN
THURSDAY. BEYOND THURSDAY...CONFIDENCE DECREASES QUITE A BIT ON
THE FORECAST AS THE GFS/ECMWF DIFFER ON WHERE TO PLACE THE
STATIONARY/WARM FRONT FRIDAY RIGHT THROUGH MEMORIAL DAY. GIVEN THE
STRENGTHENING RIDGE TO THE SOUTH AND EAST OVER NEXT WEEKEND...THE
FRONT COULD CERTAINLY BE A BREEDING GROUND FOR SEVERAL ROUNDS OF
THUNDERSTORMS AS MOISTURE RIDES UP OVER IT. IF WE EVER END UP ON
THE SOUTH END OF THE FRONT NEXT WEEKEND...RECORD TEMPS CERTAINLY
LOOK LIKE A POSSIBILITY AS H85 TEMPS ARE PROGGED TO GET UP INTO
THE MID/UPPER 20S C OVER THE CENTRAL PLAINS. THE 20.00
ECMWF/GFS...BOTH SHOW THIS FRONT WELL SOUTH OF THE AREA
FRIDAY...WITH IT SLOWLY LIFTING TO NORTH OF THE MPX AREA BY
SUNDAY.

&&

.AVIATION.../12Z TAF ISSUANCE/

MAIN ISSUES WILL BE THUNDER IN WISCONSIN AND IFR/MVFR CEILINGS IN
MN AND EVENTUALLY WISC. FRONT IS MAKING VERY SLOW PROGRESS. STILL
ONLY AT KRNH NOW AND SEEMS LIKE THE SLOWER APPROACH WILL BE
CORRECT. THUS WILL NOT BRING IT TO KEAU UNTIL EARLY AFTERNOON AND
WILL INTRODUCE ANOTHER ROUND OF THUNDER AT KEAU AT 17Z. FIRST
BATCH OF STORMS THERE NOW AND WILL MENTI0N TSRA FOR AN HOUR OR SO.

OTHER CONCERN IS MVFR/IFR CEILINGS IN RAIN-COOLED AIR.
KSTC/KRWF/KMSP ALL IFR AT THIS TIME AND EXPECT KAXN WILL GO IFR
WITH RAIN AT THEIR DOORSTEP. ONCE DEFORMATION RAIN DEPARTS AND/OR
WEAKENS... CEILINGS SHOULD SCATTER OUT LATE THIS AFTERNOON.

KMSP...
IFR CEILINGS ACROSS THE ENTIRE METRO AS WELL AS SOUTH/WEST/NORTH
OF KMSP. WITH FRONT OVER THE EASTERN METRO THERE HAVE BEEN POCKETS
OF CLEARING AND SOME SITES HAVE SEEN THEIR VISIBILITY DROP TO IFR
IN THE LAST HOUR. LAKE ELMO IS EVEN AT 1/4SM. KMSP IS NOT AS PRONE
TO FOG AS SOME OF THE EASTERN METRO AIRPORTS BUT THIS WILL NEED TO
BE WATCHED CLOSELY. OTHERWISE...THUNDER THREAT IS TO THE EAST AND
IT IS MAINLY A MATTER OF TIMING FOR THE IFR CEILINGS TO IMPROVE TO
MVFR AND THEN SCATTER OUT LATER THIS AFTERNOON.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&

$$
MPG/TDK






AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

 423 AM CDT SUN MAY 20 2012

.DISCUSSION...

RAP H5 ANALYSIS ALONG WITH WATER VAPOR IMAGERY SHOWING NEG TILTED
AND FAIRLY STRONG SHORTWAVE MOVING INTO SRN MN THIS MORNING...THAT
IS FLANKED BY FAIRLY ROBUST RIDGING OVER THE ERN GREAT LAKES AND A
WEAK RIDGE NOW MOVING ACROSS THE ROCKIES. A STRONG UPPER JET AND
DEEP UPPER LOW CAN BE SEEN ACROSS THE NRN PAC THAT IS ON ITS WAY
TOWARD WRN CANADA. AT THE SFC...A COUPLE OF COLD FRONTS WERE
ANALYZED ACROSS THE AREA THIS MORNING. THE MAIN COLD FRONT AT 330
AM STRETCHED FROM NEAR ALBERT LEA UP TO THE ASHLAND...WI
AREA...WITH A SECONDARY COLD FRONT SPLAYED OUT ACROSS MN FROM NEAR
DULUTH TO FARGO. ALONG THE PRIMARY FRONT...THERE IS A SFC
CIRCULATION NEAR ROCHESTER. TO THE WEST OF ALL OF THIS...A
SPRAWLING AREA OF HIGH PRESSURE SITS ON OUR DOORSTEP ACROSS THE
NORTHERN PLAINS.

UPPER LOW MOVING INTO SRN MN WILL BE OVER THE U.P. OF MICH BY
TONIGHT AS IT SLOWLY DE-AMPLIFIES AS IT RUNS INTO THE ERN RIDGE.
UPPER RIDGE CURRENTLY OVER THE ROCKIES WILL SLIP ACROSS THE AREA
MON/TUE AS THE UPPER LOW CURRENTLY IN THE NRN PAC MOVES TO THE BC
COAST AS SIGNIFICANT TROUGH SETS UP OVER THE NRN ROCKIES. THIS
GENERAL TROUGH/RIDGE PATTERN WILL BASICALLY REMAIN IN PLACE INTO
THE HOLIDAY WEEKEND...THOUGH BECOME CONSIDERABLY MORE
AMPLIFIED...WITH H5 HEIGHTS IN SUBTROPICAL RIDGE OVER THE OHIO
VALLEY PEGGED TO RISE ABOVE 590 DM.

AT THE SFC...COLD FRONT LOOKS TO CLEAR THE ERN MPX CWA AROUND
18Z...WITH THE SFC LOW TRACKING FROM RST UP THROUGH EAU. HIGH
PRESSURE WILL QUICKLY MOVE ACROSS THE AREA MONDAY...WITH A STRONG
LEE SIDE LOW EXPECTED TO DEVELOP OVER WRN NODAK TUESDAY. FRONTAL
FEATURE WITH THIS LOW STILL ON TRACK TO MOVE INTO WRN MN
WED...THEN STALL OUT THU NIGHT AS IT RUNS INTO THE AMPLIFYING
RIDGE TO THE SOUTH AND EAST. THE GFS/ECMWF SHOW THIS FRONT HANGING
OUT NEAR THE MPX AREA AS A WARM/STATIONARY FRONT THROUGH THE
WEEKEND...WITH NO STRONG KICKER SYSTEM INDICATED UNTIL MEMORIAL
DAY AT THE EARLIEST.

FOR TODAY THE MAIN ISSUES REVOLVE AROUND MOVING POPS OUT OF THE
AREA...HOW MUCH IF AT ALL DO TEMPS WARM UP OUTSIDE OF WRN MN...AND
HOW STRONG WILL THE WINDS BE THIS MORNING. FOR POPS...THE RAP
SHOWS THE DEFORMATION BAND OF PRECIP FOLLOWING JUST W/NW OF THE
SFC LOW. USED A BLEND OF THE HRRR/GEM/NAM TO CRAWL PRECIP ACROSS
THE AREA...WITH MOST PRECIP OUT OF MN BY 18Z...WITH RAIN CLEARING
EAU/LADYSMITH AROUND 21Z. FOR TEMPS...CONTINUED NORTH
WINDS...COMBINED WITH RAINFALL BEHIND THE COLD FRONT HAS STEADILY
BEAT TEMPERATURES BACK INTO THE 50S ACROSS THE MN PORTION OF THE
CWA...WITH 40S NOT TOO FAR AWAY. GIVEN PREFERENCE FOR HANDLING OF
PRECIP THIS MORNING BY THE GEM/NAM...USED THESE MODELS FOR HIGHS
TODAY...WHICH ENDED UP BEING FAIRLY AGGRESSIVE ON THE COLD SIDE OF
THINGS...WITH HIGHS ONLY AROUND 60 UP THE I-35 CORRIDOR. THIS COULD
BUST IN A BIG WAY IF WE CLEAR OUT FOR A COUPLE OF HOURS THIS
AFTERNOON...BUT CLEARING DOES NOT LOOK TO GET TO THE 35 CORRIDOR
SOON ENOUGH TO ALLOW MUCH OF AN IMPROVEMENT IN TEMPS TODAY. FOR
WRN WI...HIGHS WILL BE ACHIEVED BY 18Z...WITH FALLING TEMPS
EXPECTED THROUGH THE AFTERNOON. AS FOR WINDS...HAVE SEEN SOME 40
TO 50 MPH WINDS GUSTS OVERNIGHT IN CENTRAL MN. THOUGH NOT
EXPECTING ANYTHING LIKE THAT TODAY...THE HRRR DOES SHOW A FAIRLY
TIGHT PRESSURE GRADIENT DEVELOPING ON THE WRN EDGE OF THE SFC LOW
WORKING THROUGH SE MN RIGHT NOW. THE HRRR HAS BEEN DOING PRETTY
GOOD AT PICKING UP THE STRONGER WINDS THROUGH THE NIGHT...SO
LEANED HEAVILY ON IT FOR WINDS THIS MORNING...WITH SOME 20-25 MPH
SUSTAINED NORTH WINDS ACROSS ERN MN THROUGH THE MORNING.

TONIGHT...SFC RIDGE OVER THE HIGHS PLAINS WILL MOVE
OVERHEAD...WITH CLEAR SKIES...CALM WINDS...AND A LOW STARTING
POINT WITH TEMPS THIS EVENING ALL CONSPIRING FOR A RATHER COOL
MORNING ON MONDAY...WITH 40S EXPECTED AND A FEW LOWS IN THE 30S
NOT OUT OF THE QUESTION ACROSS CENTRAL MN. MONDAY WILL BE VERY
PLEASANT...WITH ONLY REAL QUESTION BEING HOW LOW DO DEWPS GO IN
THE AFTERNOON. SOUNDINGS CERTAINLY INDICATE STRONG POTENTIAL FOR
SOME GOOD MIXING OF DRIER AIR TO THE SFC AND FAVORED DEWPS MONDAY
TOWARD THE MUCH DRIER MET.

FOR MONDAY NIGHT...STRONG WAA WILL BE COMING IN ALOFT OUT AHEAD OF
THE SYSTEM DEVELOPING OVER THE WRN DAKOTAS. 20.00 GFS GENERATES
SOME ELEVATED THUNDERSTORMS IN WRN MN MON NIGHT IN THIS WAA...BUT
QUICK LOOK AT SOUNDINGS AND RH HEIGHT PROFILES SHOWS ATMO BELOW
10K FT BEING QUITE DRY...SO KEPT THE FORECAST DRY WITH THE
EXPECTATION OF ANOTHER GOOD ROUND OF ACCUS/VIRGA BREAKING OUT. OF
COURSE WITH THAT WAA...A SIGNIFICANT WARM TONGUE AT H85 IS
FORECAST BY ALL MODELS TO COME INTO WRN MN...WITH TEMPS BETWEEN 16
AND 18C NOTED. LAST WEEK THIS RESULTED IN HIGHS IN THE 90S AND
THERE IS GUIDANCE SHOWING PLACES LIKE MADISON GETTING BACK INTO
THE 90S TUESDAY. HOWEVER...THE WARM FRONT SHOULD STAY OFF TO OUR
SW...SO NOT FEELING CONFIDENT IN 90S OCCURRING AGAIN...BUT DID BUMP
WRN MN UP INTO THE MID/UPPER 80S.

AFTER THAT...WHAT LOOKS LIKE A GOOD BET IS ANOTHER ROUND OF
SHOWERS AND THUNDERSTORMS WED AFTERNOON INTO THU AS ANOTHER COLD
FRONT MOVES IN. THERE ARE TIMING DIFFERENCES WITH THIS
FRONT...WITH THE GFS SHOWING MORE WED/WED NIGHT WHILE THE ECMWF IS
MORE WED NIGHT/THU. EITHER WAY...DOES LOOK LIKE ANOTHER GOOD SHOT
AT SOME HEALTHY RAINS AS THE FRONT STALLS OUT OVER/NEAR MN
THURSDAY. BEYOND THURSDAY...CONFIDENCE DECREASES QUITE A BIT ON
THE FORECAST AS THE GFS/ECMWF DIFFER ON WHERE TO PLACE THE
STATIONARY/WARM FRONT FRIDAY RIGHT THROUGH MEMORIAL DAY. GIVEN THE
STRENGTHENING RIDGE TO THE SOUTH AND EAST OVER NEXT WEEKEND...THE
FRONT COULD CERTAINLY BE A BREEDING GROUND FOR SEVERAL ROUNDS OF
THUNDERSTORMS AS MOISTURE RIDES UP OVER IT. IF WE EVER END UP ON
THE SOUTH END OF THE FRONT NEXT WEEKEND...RECORD TEMPS CERTAINLY
LOOK LIKE A POSSIBILITY AS H85 TEMPS ARE PROGGED TO GET UP INTO
THE MID/UPPER 20S C OVER THE CENTRAL PLAINS. THE 20.00
ECMWF/GFS...BOTH SHOW THIS FRONT WELL SOUTH OF THE AREA
FRIDAY...WITH IT SLOWLY LIFTING TO NORTH OF THE MPX AREA BY
SUNDAY.

&&

.AVIATION.../06Z TAF ISSUANCE/
THE MAIN AVIATION CONCERN REMAINS THE THREAT OF THUNDERSTORMS
THROUGH SUNDAY MORNING. MESOSCALE CONVECTIVE COMPLEX WAS CENTERED
OVER SOUTHERN MN. THE BACK OF THE COMPLEX EXTENDS OVER EASTERN
SOUTH DAKOTA AND SOUTHWEST IOWA AT THIS TIME. SYSTEM WILL CONTINUE
TO ADVANCE NORTHEAST OVERNIGHT WITH SHOWERS AND THUNDERSTORMS
CONTINUING OVER MUCH OF THE FORECAST AREA. CEILINGS/VISIBILITIES
LOWER TO IFR CONDITIONS IN HEAVY RAIN. SOME SMALL HAIL IS ALSO
POSSIBLE. CONDITIONS WILL BEGIN TO IMPROVE FROM WEST TO EAST
TOWARD DAYBREAK SUNDAY IN WESTERN MN AND DURING THE AFTERNOON
SUNDAY OVER IN WESTERN WISCONSIN. EXPECT CONDS TO IMPROVE TO VFR
BEFORE NOON SUNDAY IN THE KAXN AREA...AND NOT IN THE KEAU AREA
UNTIL AFTER 300 PM. NORTH-NORTHWEST WINDS WILL CONTINUE TO USHER
IN DRIER AIR...ESPECIALLY DURING THE DAY ON SUNDAY.

KMSP...LARGE CLUSTER OF SHOWERS AND THUNDERSTORMS WILL CONTINUE TO
LIFT OVER THE AREA OVERNIGHT. EXPECT OCCASIONAL IFR WEATHER
CONDITIONS IN HEAVY RAIN AND THUNDERSTORMS.  CONDITIONS WILL BEGIN
TO IMPROVE SUNDAY AFTERNOON AS DRIER AIR FILTER OVER THE AREA. SOME
PATCHY OR AREAS OF FOG DEVELOPING IN LOW LYING AREAS SUNDAY NIGHT.

OUTLOOK...
SUN NIGHT AND MONDAY MORNING...PATCHY AREAS OF FOG.
MON-TUE...VFR.



&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&

$$

MPG/JVM






AREA FORECAST DISCUSSION

NWS JACKSON MS

 933 PM CDT MON MAY 21 2012

.UPDATE...CONVECTION CONTINUES ACROSS THE AREA...ALTHOUGH IT IS MORE
ISOLATED AT THIS POINT. THE STEAM IS FINALLY GIVING OUT AND THE
STORMS ARE WEAKENING...BUT A FEW MAY PULSE UP OVER THE NEXT HOUR OR
SO. THERE ARE STILL A FEW POCKETS OF INSTABILITY...GENERALLY OVER THE
DELTA...WHERE DEWPOINTS ARE HIGHER AND IT WAS WARMER TODAY. THE
SOUTHWEST PORTIONS OF THE AREA ALSO HAD A LITTLE INSTABILITY
LEFT...WHERE STORMS WERE MOVING ACROSS NORTHEAST LOUISIANA INTO
SOUTHWEST MISSISSIPPI. RUC ALSO SUGGESTING THERE MAY BE A SUBTLE WAVE
AROUND 850 PASSING THROUGH THE SOUTHWEST WITH SOME 20-25KT NORTHWEST
WINDS FEEDING INTO THE STORMS. ANTICIPATING THE THUNDERSTORMS TO
DIMINISH THROUGH MIDNIGHT. MAINTAINED ISOLATED SHOWERS AND
THUNDERSTORMS FOR MUCH OF THE AREA THROUGH MIDNIGHT AND REDUCED IT TO
THE SOUTH AND EAST THROUGH EARLY MORNING.

TWEAKED HOURLY VALUES TO ACCOUNT FOR WARMER TEMPERATURES AND TO
ADJUST DEWPOINTS. RAISED OVERNIGHT LOWS A DEGREE OR TWO...GUIDANCE
SUGGESTED THINGS WOULD BE NEAR 60 FOR MUCH OF THE AREA. OVERALL THE
FORECAST WAS GOOD. NO NEED FOR ANY REAL CHANGES. MAY HAVE TO UPDATE
AGAIN BEFORE MIDNIGHT. WILL SEND ZONES SHORTLY.



&&

.AVIATION...ISOLATED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS
THE AREA FOR THE NEXT FEW HOURS. HEZ WILL BE THE ONLY STATION
IMPACTED TONIGHT.THERE MAY BE A FEW SHOWERS NEAR JAN THROUGH MIDNIGHT
ALSO. OTHERWISE...SKIES WILL CONTINUE TO CLEAR FROM THE NORTHWEST.
VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST PERIOD.


&&

.PRELIMINARY POINT TEMPS/POPS...
JACKSON       59  83  54  87 /  19   3   0   7
MERIDIAN      58  82  52  87 /  20   5   0   7
VICKSBURG     57  82  51  88 /  17   4   0   7
HATTIESBURG   61  86  55  89 /  23   4   5   5
NATCHEZ       61  82  56  86 /  19   3   0  11
GREENVILLE    59  79  54  86 /   9   4   0   7
GREENWOOD     57  79  51  85 /   9   3   0   6

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&

$$

7/CME






AREA FORECAST DISCUSSION

NWS GLASGOW MT

 814 PM MDT MON MAY 21 2012

.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH WEDNESDAY...
8 PM UPDATE...AN ARC OF SHOWERS WITH A FLASH OR TWO OF THUNDER
CONTINUE TO PUSH EAST ACROSS THE CMR AND GARFIELD COUNTY THIS
EVENING. THE ARC OF SHOWERS/STORMS HAS PRODUCED 30 TO 50 MPH WIND
GUSTS AS IT PASSES OVER OBSERVATION SITES. THE LATEST HRRR MODEL
PUSHES THIS ARC THROUGH AND DIMINISHES IT THROUGH 10 PM. WILL HAVE
TO WATCH THE AREA OF SHOWERS TO THE EAST OF GREAT FALLS... THE
HRRR BRINGS THAT THROUGH THE WESTERN CMR AND UP FORT PECK LAKE
THROUGH MIDNIGHT. MAY HAVE TO UPDATE AT 10 PM TO BETTER DEFINE
OVERNIGHT POPS AND QPF.               PROTON

6 PM UPDATE...AN AREA OF THUNDERSTORMS HELD TOGETHER OVER CENTRAL
MONTANA AND IS MOVING INTO THE WESTERN ZONES. UPDATED THE FORECAST
TO ADD GUSTY WINDS SINCE UPSTREAM OBSERVATIONS HAVE SOME GUSTS TO
30 MPH. INCREASED POP COVERAGE FOR THE CMR AND THE WEST SIDE OF
FORT PECK LAKE WITH THE HRRR MODEL HITTING THIS AREA HARDER WITH
RAINFALL THIS EVENING.             PROTON

UPPER TROF OFF THE PACIFIC NORTHWEST EXPECTED TO TRANSITION INTO
MONTANA DURING THE SHORT TERM. SOUTHWEST FLOW ALOFT ALREADY
PUSHING INCREASED MOISTURE INTO THE WESTERN PART OF THE STATE AND
A FEW HIGH BASED THUNDERSTORMS ARE MOVING ACROSS CENTRAL MONTANA
THIS AFTERNOON. AIRMASS OVER EASTERN MONTANA STILL QUITE DRY AND
AFFECTED BY PROXIMITY OF RIDGE AXIS BUT JET STREAK PUSHING ACROSS
CENTRAL MONTANA INTO SOUTHERN SASKATCHEWAN OVERNIGHT WILL HELP
SPREAD THUNDERSTORMS OVER THE NORTHWEST ZONES. JET ALSO PUSHES
COLD FRONT ACROSS THE STATE OVERNIGHT AND WITH COLD AIR ADVECTION
...TIGHTENING PRESSURE GRADIENT AND DOWNSLOPE FLOW WITH JET EXPECT
WINDS TO INCREASE ACROSS THE REGION ON TUESDAY. SHOULD BE STRONG
ENOUGH FOR LAKE WIND ADVISORY BY MIDDAY...EXTENDING INTO THE
EVENING HOURS IF NOT THROUGH THE NIGHT.

STRONG WESTERLIES AND CAA BEHIND THE FRONT WILL RESULT IN SOME
INHIBITION OF SHOWERS FOR TUESDAY MORNING. ANOTHER JET STREAK
PUSHES ACROSS NORTHERN WYOMING IN THE AFTERNOON...WHICH COULD HELP
DEVELOP CONVECTION OFF THE HIGHER TERRAIN IN SOUTHWEST MONTANA AND
PUSH IT INTO THE PLAINS.

BY WEDNESDAY THE BETTER LIFT MOVES EAST AS THE UPPER TROF SLIDES
INTO MONTANA. COLD AIR ALOFT COULD RESULT IN ENOUGH INSTABILITY
FOR A FEW SHOWERS BUT OVERALL TREND WILL BE DRY AND COOL. LOW
LEVELS MIX ENOUGH THAT ANOTHER LAKE WIND ADVISORY MAY BE NEEDED.
EBERT


.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...

MADE SOME ADJUSTMENTS TO THE LONG TERM FORECAST PERIOD. A BROAD
UPPER LEVEL TROUGH WILL DOMINATE THE WEATHER PATTERN OVER THE
ROCKIES...INTER-MOUNTAIN WEST...AND NORTHERN HIGH PLAINS THROUGH
MOST OF THE EXTENDED PERIOD. LOOKS LIKE IT UNFOLD IN TWO PHASES.
FIRST...THE LONG AND BROAD UN-AMPLIFIED TROUGH WILL DROP THROUGH
THE NORTHERN ROCKIES AND NORTHERN HIGH PLAINS FROM WEDNESDAY NIGHT
THROUGH THURSDAY NIGHT.

FROM THURSDAY NIGHT ONWARD...AN UPSTREAM UPPER LEVEL LOW CENTER
LOBE BECOMES THE STAR OF THE SHOW AS IT QUICKLY DEEPENS AND DIGS
DOWN OVER THE CASCADE MOUNTAIN RANGE...BOTTOMING OUT OVER LAS
VEGAS...THEN QUICKLY CHANGING COURSE AND HEADING NORTHEAST THROUGH
SUNDAY...EVENTUALLY MOVING DIRECTLY OVER OUR CWA.

MODELS ARE IN MODERATELY GOOD AGREEMENT WITH THIS GENERAL WEATHER
PATTERN...BUT ANY MORE DETAILS GET KIND OF MUDDLED. ESPECIALLY
WITH THE NORTHWARD PROGRESSION OF THIS LATE UPPER LOW THROUGH THE
WEEKEND. THE GFS DIFFUSES AND OPENS UP THIS LOW CENTER QUITE
QUICKLY...BUT THE EC HOLDS ONTO IT AND EVEN DEEPENS IT OVER OUR
CWA WHICH WOULD RESULT IN MUCH COLDER TEMPERATURES THAN WE HAVE
CURRENTLY FORECASTED.

TRIED TO SHOW AN EXTENDED MODEL BLEND...BUT DID NOT GIVE EQUAL
WEIGHT TO THE EXTREME EC OUTLIER AND WOULD ADVISE DOING SO UNTIL
EXTENDED MODELS SHOW BETTER AGREEMENT.

OVERALL...EXPECT ALTERNATING PERIODS OF RAIN SHOWERS AND DRY SLOTS
WITH GENERALLY COOLER TEMPERATURES AS THIS LARGE UPPER TROUGH
SYSTEM SPREADS ACROSS MOST OF THIS PORTION OF THE CONTINENT.
BMICKELSON

PREVIOUS LONG TERM DISCUSSION...MODELS TAKE ONE UPPER TROUGH TO
THE EAST THURSDAY AND THURSDAY NIGHT WHILE DIGGING ANOTHER OVER
THE PACIFIC NORTHWEST. WHILE THE BULK OF THE MOISTURE WITH
THURSDAY`S TROUGH IS EXPECTED TO BE TO THE EAST...THERE WILL BE
ENOUGH LINGERING MOISTURE AND INSTABILITY TO WARRANT A CHANCE OF
SHOWERS.

ON FRIDAY...THE FORECAST WILL BE BETWEEN SYSTEMS IN A SOUTHWEST
FLOW ALOFT AS A CLOSED LOW DEVELOPS IN CALIFORNIA IN THE WEST
COAST UPPER TROUGH. MODELS DIFFER BETWEEN A DRY SW FLOW (GFS) AND
MOIST SW FLOW (ECMWF) ALOFT. WILL MAINTAIN EITHER A CHANCE OR
SLIGHT CHANCE OF SHOWERS.

MODELS GRADUALLY LIFT THIS LOW NORTH OVER THE WEEKEND AND BRING IT
ACROSS MONTANA ON SUNDAY. IF THIS FORECAST HOLDS TRUE...IT COULD
BE A VERY WET WEEKEND ACROSS THE REGION. WILL MAINTAIN A CHANCE
OF SHOWERS FOR NOW UNTIL BETTER RUN TO RUN AGREEMENT IS
MAINTAINED.

THE LOW LIFTS NORTH NEXT MONDAY DIMINISHING THE CHANCE OF SHOWERS. FORRESTER


&&

.AVIATION...
AN APPROACHING PACIFIC LOW PRESSURE SYSTEM WILL BRING INCREASED
CLOUDINESS AND RAIN SHOWERS TO NORTHEAST MONTANA TOWARD THE END OF
THIS TAF PERIOD. VFR CONDITIONS ARE EXPECTED TO PREVAIL WITH ONE
BRIEF EXCEPTION...KGGW MAY SEE MVFR CONDITIONS WITH A BRIEF RAIN
SHOWER TONIGHT AND AGAIN BY MID DAY TUESDAY. A COLD FRONT WILL
PUSH RAIN SHOWERS AND POSSIBLY A FEW THUNDERSTORMS THROUGH THE
ENTIRE REGION. WINDS WILL SHIFT AROUND TO COME FROM THE NORTHWEST AND
WEST DURING THE LATE MORNING HOURS ON TUESDAY...THEN INCREASE INTO
THE 25G35KT RANGE BY MID DAY. OVERALL...EXPECT INCREASED CROSSWIND
CONCERNS FOR NORTH TO SOUTH ORIENTED RUNWAYS DURING THE MID DAY
AND AFTERNOON HOURS ON TUESDAY WITH BRIEF MODERATE RAIN SHOWERS.
BMICKELSON


&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...
LAKE WIND ADVISORY FROM 10 AM TO 9 PM MDT TUESDAY FOR FORT PECK
LAKE.

&&

$$

WEATHER.GOV/GLASGOW






AREA FORECAST DISCUSSION...UPDATED

NWS GLASGOW MT

 535 PM MDT MON MAY 21 2012

.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH WEDNESDAY...
UPDATE...AN AREA OF THUNDERSTORMS HELD TOGETHER OVER CENTRAL
MONTANA AND IS MOVING INTO THE WESTERN ZONES. UPDATED THE FORECAST
TO ADD GUSTY WINDS SINCE UPSTREAM OBSERVATIONS HAVE SOME GUSTS TO
30 MPH. INCREASED POP COVERAGE FOR THE CMR AND THE WEST SIDE OF
FORT PECK LAKE WITH THE HRRR MODEL HITTING THIS AREA HARDER WITH
RAINFALL THIS EVENING.             PROTON

UPPER TROF OFF THE PACIFIC NORTHWEST EXPECTED TO TRANSITION INTO
MONTANA DURING THE SHORT TERM. SOUTHWEST FLOW ALOFT ALREADY
PUSHING INCREASED MOISTURE INTO THE WESTERN PART OF THE STATE AND
A FEW HIGH BASED THUNDERSTORMS ARE MOVING ACROSS CENTRAL MONTANA
THIS AFTERNOON. AIRMASS OVER EASTERN MONTANA STILL QUITE DRY AND
AFFECTED BY PROXIMITY OF RIDGE AXIS BUT JET STREAK PUSHING ACROSS
CENTRAL MONTANA INTO SOUTHERN SASKATCHEWAN OVERNIGHT WILL HELP
SPREAD THUNDERSTORMS OVER THE NORTHWEST ZONES. JET ALSO PUSHES
COLD FRONT ACROSS THE STATE OVERNIGHT AND WITH COLD AIR ADVECTION
...TIGHTENING PRESSURE GRADIENT AND DOWNSLOPE FLOW WITH JET EXPECT
WINDS TO INCREASE ACROSS THE REGION ON TUESDAY. SHOULD BE STRONG
ENOUGH FOR LAKE WIND ADVISORY BY MIDDAY...EXTENDING INTO THE
EVENING HOURS IF NOT THROUGH THE NIGHT.

STRONG WESTERLIES AND CAA BEHIND THE FRONT WILL RESULT IN SOME
INHIBITION OF SHOWERS FOR TUESDAY MORNING. ANOTHER JET STREAK
PUSHES ACROSS NORTHERN WYOMING IN THE AFTERNOON...WHICH COULD HELP
DEVELOP CONVECTION OFF THE HIGHER TERRAIN IN SOUTHWEST MONTANA AND
PUSH IT INTO THE PLAINS.

BY WEDNESDAY THE BETTER LIFT MOVES EAST AS THE UPPER TROF SLIDES
INTO MONTANA. COLD AIR ALOFT COULD RESULT IN ENOUGH INSTABILITY
FOR A FEW SHOWERS BUT OVERALL TREND WILL BE DRY AND COOL. LOW
LEVELS MIX ENOUGH THAT ANOTHER LAKE WIND ADVISORY MAY BE NEEDED.
EBERT


.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...

MADE SOME ADJUSTMENTS TO THE LONG TERM FORECAST PERIOD. A BROAD
UPPER LEVEL TROUGH WILL DOMINATE THE WEATHER PATTERN OVER THE
ROCKIES...INTER-MOUNTAIN WEST...AND NORTHERN HIGH PLAINS THROUGH
MOST OF THE EXTENDED PERIOD. LOOKS LIKE IT UNFOLD IN TWO PHASES.
FIRST...THE LONG AND BROAD UN-AMPLIFIED TROUGH WILL DROP THROUGH
THE NORTHERN ROCKIES AND NORTHERN HIGH PLAINS FROM WEDNESDAY NIGHT
THROUGH THURSDAY NIGHT.

FROM THURSDAY NIGHT ONWARD...AN UPSTREAM UPPER LEVEL LOW CENTER
LOBE BECOMES THE STAR OF THE SHOW AS IT QUICKLY DEEPENS AND DIGS
DOWN OVER THE CASCADE MOUNTAIN RANGE...BOTTOMING OUT OVER LAS
VEGAS...THEN QUICKLY CHANGING COURSE AND HEADING NORTHEAST THROUGH
SUNDAY...EVENTUALLY MOVING DIRECTLY OVER OUR CWA.

MODELS ARE IN MODERATELY GOOD AGREEMENT WITH THIS GENERAL WEATHER
PATTERN...BUT ANY MORE DETAILS GET KIND OF MUDDLED. ESPECIALLY
WITH THE NORTHWARD PROGRESSION OF THIS LATE UPPER LOW THROUGH THE
WEEKEND. THE GFS DIFFUSES AND OPENS UP THIS LOW CENTER QUITE
QUICKLY...BUT THE EC HOLDS ONTO IT AND EVEN DEEPENS IT OVER OUR
CWA WHICH WOULD RESULT IN MUCH COLDER TEMPERATURES THAN WE HAVE
CURRENTLY FORECASTED.

TRIED TO SHOW AN EXTENDED MODEL BLEND...BUT DID NOT GIVE EQUAL
WEIGHT TO THE EXTREME EC OUTLIER AND WOULD ADVISE DOING SO UNTIL
EXTENDED MODELS SHOW BETTER AGREEMENT.

OVERALL...EXPECT ALTERNATING PERIODS OF RAIN SHOWERS AND DRY SLOTS
WITH GENERALLY COOLER TEMPERATURES AS THIS LARGE UPPER TROUGH
SYSTEM SPREADS ACROSS MOST OF THIS PORTION OF THE CONTINENT.
BMICKELSON

PREVIOUS LONG TERM DISCUSSION...MODELS TAKE ONE UPPER TROUGH TO
THE EAST THURSDAY AND THURSDAY NIGHT WHILE DIGGING ANOTHER OVER
THE PACIFIC NORTHWEST. WHILE THE BULK OF THE MOISTURE WITH
THURSDAY`S TROUGH IS EXPECTED TO BE TO THE EAST...THERE WILL BE
ENOUGH LINGERING MOISTURE AND INSTABILITY TO WARRANT A CHANCE OF
SHOWERS.

ON FRIDAY...THE FORECAST WILL BE BETWEEN SYSTEMS IN A SOUTHWEST
FLOW ALOFT AS A CLOSED LOW DEVELOPS IN CALIFORNIA IN THE WEST
COAST UPPER TROUGH. MODELS DIFFER BETWEEN A DRY SW FLOW (GFS) AND
MOIST SW FLOW (ECMWF) ALOFT. WILL MAINTAIN EITHER A CHANCE OR
SLIGHT CHANCE OF SHOWERS.

MODELS GRADUALLY LIFT THIS LOW NORTH OVER THE WEEKEND AND BRING IT
ACROSS MONTANA ON SUNDAY. IF THIS FORECAST HOLDS TRUE...IT COULD
BE A VERY WET WEEKEND ACROSS THE REGION. WILL MAINTAIN A CHANCE
OF SHOWERS FOR NOW UNTIL BETTER RUN TO RUN AGREEMENT IS
MAINTAINED.

THE LOW LIFTS NORTH NEXT MONDAY DIMINISHING THE CHANCE OF SHOWERS. FORRESTER


&&

.AVIATION...
AN APPROACHING PACIFIC LOW PRESSURE SYSTEM WILL BRING INCREASED
CLOUDINESS AND RAIN SHOWERS TO NORTHEAST MONTANA TOWARD THE END OF
THIS TAF PERIOD. VFR CONDITIONS ARE EXPECTED TO PREVAIL WITH ONE
BRIEF EXCEPTION...KGGW MAY SEE MVFR CONDITIONS WITH A BRIEF RAIN
SHOWER TONIGHT AND AGAIN BY MID DAY TUESDAY. A COLD FRONT WILL
PUSH RAIN SHOWERS AND POSSIBLY A FEW THUNDERSTORMS THROUGH THE
ENTIRE REGION. WINDS WILL SHIFT AROUND TO COME FROM THE NORTHWEST AND
WEST DURING THE LATE MORNING HOURS ON TUESDAY...THEN INCREASE INTO
THE 25G35KT RANGE BY MID DAY. OVERALL...EXPECT INCREASED CROSSWIND
CONCERNS FOR NORTH TO SOUTH ORIENTED RUNWAYS DURING THE MID DAY
AND AFTERNOON HOURS ON TUESDAY WITH BRIEF MODERATE RAIN SHOWERS.
BMICKELSON


&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...
LAKE WIND ADVISORY FROM 10 AM TO 9 PM MDT TUESDAY FOR FORT PECK
LAKE.

&&

$$

WEATHER.GOV/GLASGOW






AREA FORECAST DISCUSSION

NWS HASTINGS NE

 1244 PM CDT SUN MAY 20 2012

.AVIATION...18Z TAF. QUIET WEATHER EXPECTED FOR THIS TAF
PERIOD...AND OUTSIDE OF THE POSSIBILITY FOR AN OCCASIONAL HIGH END
MVFR CEILING FOR A COUPLE HOURS EARLY THIS AFTERNOON...VFR
CONDITIONS WILL REIGN. SURFACE HIGH PRESSURE CURRENTLY CENTERED
OVER WRN NEB...WHICH WILL KEEP WINDS GENERALLY NORTHERLY THROUGH
THE AFTERNOON...WITH DIMINISHING SPEEDS. THROUGH THE
EVENING/OVERNIGHT HOURS AND INTO TOMORROW...WINDS WILL REMAIN
FAIRLY LIGHT...AND GRADUALLY BECOME MORE EASTERLY...THEN
SOUTHEASTERLY AS THE SURFACE HIGH SLIDES OFF TO THE EAST OF THE
CWA.

&&

PREV DISCUSSION... /ISSUED 440 AM CDT SUN MAY 20 2012/

SHORT TERM...THROUGH TUESDAY NIGHT. OFFICIALLY...THE FORECAST
REMAINS DRY THROUGH THESE 72 HOURS. HOWEVER...THIS WILL NEED
WATCHED CLOSELY AS THERE ARE AT LEAST A FEW OPPORTUNITIES FOR
THUNDERSTORMS TO POTENTIALLY SNEAK INTO THE FORECAST. OF HIGHER
CONFIDENCE IS POSSIBLE ADVISORY-CRITERIA WINDS ON TUESDAY.

08Z OBJECTIVE SURFACE ANALYSIS PLACES THE CWA BETWEEN A 1010MB LOW
OVER WESTERN IA...AND A 1021MB HIGH STRETCHED NORTH-SOUTH ACROSS
THE PANHANDLE INTO EASTERN CO. AS A RESULT...BREEZES EARLY THIS
MORNING ARE LARGELY FROM THE WEST-NORTHWEST AREA WIDE...BUT
RANGING FROM VERY LIGHT IN THE FAR WESTERN COUNTIES...TO GUSTS
STILL AROUND 20 MPH IN THE EAST WHERE THE GRADIENT REMAINS
TIGHTEST. WATER VAPOR IMAGERY CLEARLY DEPICTS THE DEPARTING
SHORTWAVE RESPONSIBLE FOR YESTERDAY/S ROUND OF SEVERE WEATHER NOW
OVER NORTHEAST NEB...WITH BROAD QUASI-ZONAL FLOW ALOFT EXTENDING
BACK UPSTREAM TO THE EASTERN PACIFIC. RADAR AND 11-3.9 MICRON
SATELLITE IMAGERY CONFIRMS A STUBBORN AREA OF LINGERING LIGHT RAIN
THAT HAS FINALLY PUSHED OUT OF THE NORTHEASTERN CWA...IN ASSOCIATION
WITH THE PARENT AREA OF MID LEVEL CONVERGENCE/SATURATION ON THE
BACKSIDE OF THE EXITING SHORTWAVE. MEANWHILE...OFF TO THE SOUTH A
VERY NARROW BAND OF LIGHT RAIN/SPRINKLES IS MAKING ITS WAY ACROSS
PARTS OF CENTRAL KS...LIKELY DUE TO SOME SUBTLE MID LEVEL
FRONTOGENESIS IN THE ENTRANCE REGION OF A MID-UPPER JET STREAK
PULLING ACROSS NORTHERN KS/SOUTHEAST NEB.

FOLLOWING THE 05Z HRRR REFLECTIVITY CLOSELY...ALONG WITH LATEST
RADAR TRENDS...LOOKS LIKE ANY SPRINKLES IN NEB ZONES SHOULD
PRETTY MUCH BE GONE BY SUNRISE...SO WILL NOT CARRY A PRE-FIRST
PERIOD ZONE ISSUANCE TO COVER IT. AS FOR THE KS SPRINKLES...NOT
EXPECTING THESE TO BE AN ISSUE PAST SUNRISE EITHER...BUT WILL
CARRY A SLIGHT CHANCE SPRINKLE MENTION ACROSS THE FAR SOUTHERN CWA
THROUGH 12Z JUST IN CASE SOMETHING SNEAKS IN. OTHERWISE...A DRY
AND SEASONABLY PLEASANT DAY IS IN STORE. ALOFT...THE DEPARTING
SHORTWAVE AXIS WILL BE WELL UP INTO WESTERN WI BY 00Z...WITH
BROAD...MODESTLY AMPLIFIED RIDGING EXTENDING FROM THE WEST COAST
TO CENTRAL PLAINS IN ITS WAKE. AT THE SURFACE...A RIDGE AXIS WILL
GRADUALLY PASS ACROSS THE CWA THROUGH THE DAY...TRANSITIONING
WINDS FROM NORTHERLY THROUGH MUCH OF THE DAY TO MORE EASTERLY BY
DAY/S END. WITH THIS CENTER OF THIS HIGH TO THE NORTH OF THE AREA
THIS MORNING...THERE SHOULD BE AN INCREASE IN WIND SPEEDS MOST
AREAS AS BOUNDARY LAYER MIXING COMMENCES...WITH SUSTAINED SPEEDS
EASILY 10-15 MPH FOR SEVERAL HOURS...BEFORE SUBSIDING A BIT DURING
THE AFTERNOON. ALTHOUGH COULD SEE SOME LINGERING CLOUDS THIS
MORNING...AND MAYBE EVEN SOME DAYTIME FAIR WEATHER CUMULUS
DEVELOPMENT MAINLY IN EASTERN ZONES...THE CWA AS A WHOLE SHOULD
AVERAGE MOSTLY SUNNY TODAY. AS A RESULT...ANTICIPATE A FAIRLY
EFFICIENT WARM UP...AND KEPT HIGHS SIMILAR TO PREVIOUS
FORECAST...AND FAVORING THE WARMER MET GUIDANCE/RAW NAM SOLUTION
VERSUS COOLER MAV/GFS. THUS HAVE THE MAJORITY OF THE CWA REACHING
THE 72-76 RANGE.

TONIGHT...THE BROAD WESTERN TO CENTRAL CONUS RIDGE AMPLIFIES A
BIT...WITH MODEST MID LEVEL HEIGHT RISES OVER THE CENTRAL PLAINS
AS THE UPPER LEVEL FLOW BECOMES MORE NORTHERLY VERSUS WESTERLY
AROUND THE EASTERN PERIPHERY OF THE RIDGE. ALTHOUGH HAVE LEFT ALL
THUNDERSTORM MENTION OUT OF THE FORECAST FOR NOW...WILL HAVE TO KEEP
A CLOSE EYE ON FAR NORTHWEST ZONES AFTER MIDNIGHT AND ESPECIALLY
TOWARD SUNRISE...AS BOTH THE NAM/GFS ADVERTISE MODEST ELEVATED
THETA-E ADVECTION EVIDENT AT 700MB PUSHING EAST OUT OF WESTERN
NEB...ALONG WITH MAYBE UP TO A FEW HUNDRED J/KG MUCAPE ROOTED IN
THE 850-700MB LAYER. BOTH OF THESE MODELS KEEP CONVECTIVE QPF AT
LEAST SLIGHTLY NORTHWEST OF THE CWA OVER THE SANDHILLS...AND THE
00Z 4KM WRF-NMM SHOWS LITTLE HINT OF DEVELOPING CONVECTION...BUT
THIS WILL NEED CLOSELY WATCHED AS THIS KIND OF FORCING OFTEN LEADS
TO CLASSIC SUNRISE SURPRISE SHOWERS/WEAK STORMS. FOR LOW TEMPS
TONIGHT...WITH GENERALLY LIGHT EAST-SOUTHEAST BREEZES AND MOSTLY
CLEAR SKIES...OPTED TO LOWER LOWS 1-3 DEGREES FROM PREVIOUS
FORECAST...WITH MOST AREAS BETWEEN 44-48.

MONDAY...RIDGING WILL CONTINUE TO DOMINATE THE MID/UPPER
LEVELS...WITH THE AXIS GENERALLY ALIGNED ALONG THE ROCKIES...AND
CONTINUED NORTH-NORTHWEST FLOW ALOFT OVER THE CENTRAL PLAINS. AS
THE SURFACE RIDGE AXIS DEPARTS FARTHER EAST AND MODEST PRESSURE
FALLS OCCUR OVER THE HIGH PLAINS...SOUTHERLY WINDS WILL BECOME
ESTABLISHED...AND UPPED SUSTAINED SPEEDS SLIGHTLY WITH MOST OF THE
CWA SOLIDLY INTO THE 15-20 MPH RANGE MUCH OF THE DAY. DESPITE
MODEST LOW LEVEL MOISTURE RETURN WITH SURFACE DEWPOINTS POSSIBLY
APPROACHING 50 ACROSS THE WESTERN CWA...THE PRIMARY LOW LEVEL
INSTABILITY AXIS SHOULD SET UP AT LEAST 1-2 COUNTIES WEST OF THE
CWA DURING THE AFTERNOON...WITH THE NAM KEEPING ANY LATE AFTERNOON
CONVECTION SAFELY NORTHWEST OF THE AREA ACROSS THE SANDHILLS.
ASSUMING THAT NO SHOWERS/WEAK STORMS DO IN FACT DEVELOP EARLY IN
THE MORNING AS DISCUSSED ABOVE...HAVE FAIRLY HIGH CONFIDENCE IN
LEAVING STORMS OUT THROUGH THE AFTERNOON HOURS...DESPITE SPC
ASSIGNING A GENERAL THUNDER AREA TO MUCH OF THE WESTERN CWA ON THE
DAY2 OUTLOOK. WITH SOUTHERLY FLOW AND AFTERNOON MIXING TO AROUND
800MB PER NAM SOUNDINGS...KEPT HIGH TEMPS SIMILAR TO PREVIOUS
FORECAST...AND GENERALLY 2-4 DEGREES ABOVE MET/MAV GUIDANCE
CONSENSUS...WITH MOST AREAS 79-82.

MONDAY NIGHT...THE MID/UPPER RIDGE AXIS BECOMES MORE POSITIVELY
TILTED AND EXTENDS DIRECTLY THROUGH THE CENTRAL PLAINS...AS THE
RIDGE STARTS ITS EASTWARD PUSH IN RESPONSE TO AN INCOMING
SHORTWAVE AND ASSOCIATED UPPER JET STREAK MOVING INTO THE PACIFIC
NORTHWEST. ASSUMING THAT NO SANDHILLS CONVECTION SNEAKS INTO THE
CWA DURING THE EVENING...WILL STAY THE COURSE WITH A STORM-FREE
FORECAST THROUGH THE NIGHT...ALTHOUGH THIS WILL ALSO BEAR WATCHING
AS BOTH THE NAM/GFS ADVERTISE A BATCH OF ELEVATED INSTABILITY ON
THE ORDER OF 500-1000 J/KG SLIDING EAST OVER THE CWA DURING THE
NIGHT. THINKING AT THIS POINT IS THAT THESE PARCELS SHOULD REMAIN
CAPPED IN THE PRESENCE OF VERY LITTLE UPPER FORCING...WITH BETTER
CONVERGENCE ALONG THE NOSE OF THE LOW LEVEL JET AIMED MORE INTO
THE OAX CWA TOWARD THE MO RIVER...WHERE THE NAM ACTUALLY DOES
DEVELOP SOME CONVECTIVE QPF. CERTAINLY CANNOT COMPLETELY RULE OUT
A FEW SHOWERS/STORMS FLARING UP AND LATER SHIFTS MAY HAVE TO
CONSIDER ADDING A SLIGHT POP SOMEWHERE.

TUESDAY...INSTABILITY INCREASES FURTHER...AS SURFACE DEWPOINTS
CLIMB BACK INTO THE LOW-MID 50S...BUT WITH INCOMING NORTHWEST
CONUS SHORTWAVE REMAINING TO THE WEST...THIS SHOULD BE NOTHING
MORE THAN A WARM AND RATHER WINDY DAY...WITH NEAR-SURFACE PARCELS
CAPPED OFF AS SUGGESTED BY 700MB TEMPS INTO THE 11-13C RANGE. ANY
LATE AFTERNOON STORMS THAT MIGHT MANAGE TO DEVELOP IN THE REGION
SHOULD FOCUS WEST OF THE CWA NEARER THE PRIMARY SYNOPTIC DRYLINE.
AS A RESULT...EXPECT THE BIG STORY TUESDAY TO BE STRONG SOUTHERLY
WINDS...AS BOTH THE NAM/GFS DEEPEN A 989-992MB LOW OVER THE HIGH
PLAINS OVER THE COURSE OF THE DAY. THE RESULTANT STRENGTHENING
PRESSURE GRADIENT...ALONG WITH MIXING TO AT LEAST 750MB MOST
AREAS...SHOULD REALLY GET SOUTHERLY WINDS GOING. PREVIOUS FORECAST
ALREADY HAD PARTS OF THE AREA REACHING ADVISORY CRITERIA OF
SUSTAINED 30 MPH...AND GENERALLY KEPT THIS THEME INTACT...WITH THE
HIGHEST SPEEDS FOCUSED ACROSS THE WESTERN 1/2 OF THE CWA. WITH
THIS STILL BEING 5 PERIODS OUT...WAY TOO EARLY FOR A
HEADLINE...BUT WILL CONTINUE TO HIGHLIGHT IN THE HAZARDOUS WEATHER
OUTLOOK. EXPECTING MINIMAL CLOUD COVER...THIS SHOULD BE A CLASSIC
BIG WARM UP...DECENT DEWPOINT MIX-DOWN KIND OF DAY...AND HAVE
DEWPOINTS FALLING A BIT IN THE AFTERNOON...ESPECIALLY WEST. TEMP
WISE...NUDGED UP HIGHS 2-3 DEGREES FROM PREVIOUS FORECAST MOST
AREAS...AIMING FOR 89-92 MOST AREAS...AND EVEN MID 90S SOUTHWEST.
ALTHOUGH THIS IS SEVERAL DEGREES ABOVE MET/MAV GUIDANCE
CONSENSUS...IT IS MORE IN LINE WITH RAW NAM TEMPS...AND DAYS LIKE
THIS HAVE PROVEN SEVERAL TIMES IN THE PAST FEW WEEKS THAT WARMER
IS THE WAY TO GO.

TUESDAY NIGHT...YET AGAIN KEPT THE AREA FREE OF STORM
MENTION...DESPITE THE GFS TRYING TO SNEAK SOME ACTIVITY INTO
NORTHEAST ZONES AFTER MIDNIGHT. DESPITE INCREASING FORCING FROM
THE INCOMING SHORTWAVE...MOST OF THIS ENERGY WILL REMAIN BACK OVER
THE NORTHERN ROCKIES/NORTHERN PLAINS...AND BESIDES BOTH THE
NAM/GFS ADVERTISE A CONSIDERABLE CAPPING INVERSION WITH A 700MB
THERMAL RIDGE OF 13C+ SETTING UP OVER THE CWA DURING THE NIGHT.
NOT SURPRISINGLY...MODEL CONSENSUS IS TO FOCUS CONVECTION NORTH OF
THE CWA THROUGH THE NIGHT...NEAR AND JUST BEHIND AN INCOMING
SURFACE COLD FRONT AND IN AREA OF SLIGHTLY COOLER MID LEVEL TEMPS.
WILL HAVE TO IRON OUT SOME DETAILS REGARDING THE SPEED OF THIS
INCOMING COLD FRONT HOWEVER...AS BY 12Z WEDNESDAY THE NAM ALREADY
HAS THE FRONT INTO THE WESTERN CWA...WHILE THE ECMWF STILL HAS IT
BACK IN WESTERN NEB. IF ANY STORMS DO MANAGE TO DEVELOP INTO THE
NORTHERN CWA DURING THE NIGHT...STRONG TO SEVERE IS CERTAINLY
POSSIBLE...BUT CONFIDENCE STILL REMAINS LOW ENOUGH REGARDING
STORM DEVELOPMENT TO KEEP POPS BELOW THE 20 PERCENT SLIGHT CHANCE
THRESHOLD.

LONG TERM...TARTING 12Z WEDNESDAY. GUIDANCE FROM THE OPERATIONAL
GFS AND EC SUGGEST A MID LEVEL SHORT WAVE...PERHAPS A CLOSED LOW
PER THE GFS...WILL PUSH ACROSS THE NORTHERN PLAINS AND SOUTH
CENTRAL CANADA WEDNESDAY AND THURSDAY. AN ASSOCIATED SURFACE LOW
IS ALSO EXPECTED TO PUSH EAST ACROSS THE NORTHERN PLAINS AND SOUTH
CENTRAL CANADA THUS ALLOWING A LOW LEVEL BAROCLINIC ZONE TO PUSH
ACROSS OUR AREA DURING THE DAY WEDNESDAY. SURFACE RIDGING IS THEN
EXPECTED TO INFILTRATE THE CENTRAL PLAINS LATE WEDNESDAY THROUGH
EARLY FRIDAY BEFORE LOW LEVEL RETURN FLOW IS REALIZED ACROSS OUR
AREA LATE FRIDAY INTO SATURDAY.

THE OPERATIONAL GFS AND EC BOTH CONTINUE TO INDICATE CONVECTION
ALONG THE LOW LEVEL BAROCLINIC ZONE WEDNESDAY AFTERNOON AND EVENING.
THE OPERATIONAL GFS IS BECOMING SOMEWHAT MORE PROGRESSIVE AND NOW
SUGGESTS CONVECTION WILL FIRE EAST OF OUR CWA WELL AFTER THE LOW
LEVEL BAROCLINIC ZONE HAS CLEARED OUR AREA. THE EC ON THE OTHER HAND
SUGGESTS A SLIGHTLY SLOWER FROPA WITH CONVECTION POSSIBLE ALONG THE
EASTERN HALF OF OUR CWA LATE WEDNESDAY AFTERNOON INTO WEDNESDAY
EVENING. WITH 0-1KM MLCAPE VALUES PERHAPS APPROACHING 1500J/KG AND
DEEP LAYER BULK SHEAR VALUES IN THE NEIGHBORHOOD OF 40KTS...LARGE
HAIL AND PERHAPS STRONG WINDS CANNOT BE RULED OUT SHOULD
CONVECTION BE REALIZED OVER OUR AREA ALONG THE LOW LEVEL BAROCLINIC
ZONE WEDNESDAY. OPTED TO PLAY IT SAFE SINCE THE EC CONTINUES TO
SUGGEST THIS POSSIBILITY AND KEPT CONVECTION IN THE FORECAST ACROSS
THE EASTERN HALF OF THE CWA...WITH A SEVERE MENTION ALSO IN THE HWO
FOR LATE WEDNESDAY AFTERNOON INTO WEDNESDAY EVENING.

MID AND UPPER LEVEL JET ENERGY IS EXPECTED TO PUSH OVERHEAD
THE CENTRAL PLAINS LATE WEDNESDAY...WITH THE LEFT-FRONT QUAD OF A
60-70KT MID LEVEL JET STREAK EXPECTED TO SET UP SHOP OVER OUR AREA
WEDNESDAY NIGHT INTO THURSDAY MORNING. AN INDIRECT THERMAL
CIRCULATION MAY PRODUCE ENOUGH LIFT FOR PRECIPITATION
PRODUCTION...ASSUMING ENOUGH LOW TO MID LEVEL MOISTURE...AND QPF
FIELDS FROM THE OPERATIONAL GFS AND EC BOTH SUGGEST PRECIPITATION
WILL BE REALIZED WEDNESDAY NIGHT/THURSDAY MORNING. WENT AHEAD WITH
POPS LATE WEDNESDAY INTO EARLY THURSDAY AS A RESULT. THE RIGHT-REAR
QUADRANT OF THE SAME MID LEVEL JET STREAK IS THEN EXPECTED TO PUSH
OVER NORTHERN PORTIONS OF THE CWA THURSDAY NIGHT INTO FRIDAY
MORNING...THUS BRINGING ANOTHER CHANCE FOR PRECIPITATION TO NORTHERN
PORTIONS OF OUR AREA. THE INTRODUCTION OF A ~40KT LOW LEVEL JET
STREAK WILL THEN BRING FURTHER CHANCES OF PRECIPITATION TO THE AREA
FRIDAY NIGHT INTO EARLY SATURDAY. BEYOND WEDNESDAY EVENING...LOW
LEVEL MOISTURE IS NOT OVERLY IMPRESSIVE AS SURFACE RIDGING REMAINS
ENTRENCHED ACROSS THE AREA AND AS A RESULT...INSTABILITY SUFFERS
GREATLY. LOW LEVEL MOISTURE FINALLY IMPROVES BY LATE FRIDAY AS LOW
LEVEL RETURN FLOW IS REALIZED ACROSS THE AREA...WITH DEEP LAYER
MUCAPE VALUES PERHAPS CLIMBING TO AROUND 1000J/KG BY FRIDAY NIGHT.
GIVEN ALL THIS...AM NOT INCLINED TO GO WITH ANY SEVERE WORDING IN
THE HWO BEYOND WEDNESDAY EVENING.

A SUBTLE COOLING TREND SHOULD BE NOTED ACROSS THE AREA WEDNESDAY AND
THURSDAY AS SURFACE RIDGING REMAINS OVER THE AREA. LOW LEVEL RETURN
FLOW AND RESULTANT LOW LEVEL WARM AIR ADVECTION WILL THEN PROMOTE A
WARMING TREND TO FINISH OUT THE EXTENDED FORECAST PERIOD. DESPITE
ANY TRENDS...TEMPERATURES DURING THE EXTENDED FORECAST PERIOD WILL
REMAIN AT NEAR OR ABOVE-NORMAL LEVELS FOR THIS TIME OF YEAR.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

AVIATION...ADO
SHORT...PFANNKUCH
LONG...BRYANT






AREA FORECAST DISCUSSION

NWS HASTINGS NE

 550 AM CDT SUN MAY 20 2012

.AVIATION...12Z KGRI TAF. VFR CONDITIONS TO CONTINUE THROUGH THE
NEXT 24 HOURS. SATELLITE IMAGERY INDICATES SKIES ARE CLEARING OUT
ACROSS SOUTH CENTRAL NEBRASKA...WITH CLEAR SKIES EXPECTED BY 15Z.
SURFACE WINDS WILL REMAIN FROM THE NORTH/NORTHWEST BUT WEAKEN
THROUGH THE DAY...BECOMING LIGHT AND VARIABLE OVERNIGHT. VISIBILITY
RESTRICTIONS ARE NOT EXPECTED THROUGH THE NEXT 24 HOURS.

&&

.PREV DISCUSSION... /ISSUED 440 AM CDT SUN MAY 20 2012/

SHORT TERM...THROUGH TUESDAY NIGHT. OFFICIALLY...THE FORECAST
REMAINS DRY THROUGH THESE 72 HOURS. HOWEVER...THIS WILL NEED
WATCHED CLOSELY AS THERE ARE AT LEAST A FEW OPPORTUNITIES FOR
THUNDERSTORMS TO POTENTIALLY SNEAK INTO THE FORECAST. OF HIGHER
CONFIDENCE IS POSSIBLE ADVISORY-CRITERIA WINDS ON TUESDAY.

08Z OBJECTIVE SURFACE ANALYSIS PLACES THE CWA BETWEEN A 1010MB LOW
OVER WESTERN IA...AND A 1021MB HIGH STRETCHED NORTH-SOUTH ACROSS
THE PANHANDLE INTO EASTERN CO. AS A RESULT...BREEZES EARLY THIS
MORNING ARE LARGELY FROM THE WEST-NORTHWEST AREA WIDE...BUT
RANGING FROM VERY LIGHT IN THE FAR WESTERN COUNTIES...TO GUSTS
STILL AROUND 20 MPH IN THE EAST WHERE THE GRADIENT REMAINS
TIGHTEST. WATER VAPOR IMAGERY CLEARLY DEPICTS THE DEPARTING
SHORTWAVE RESPONSIBLE FOR YESTERDAY/S ROUND OF SEVERE WEATHER NOW
OVER NORTHEAST NEB...WITH BROAD QUASI-ZONAL FLOW ALOFT EXTENDING
BACK UPSTREAM TO THE EASTERN PACIFIC. RADAR AND 11-3.9 MICRON
SATELLITE IMAGERY CONFIRMS A STUBBORN AREA OF LINGERING LIGHT RAIN
THAT HAS FINALLY PUSHED OUT OF THE NORTHEASTERN CWA...IN ASSOCIATION
WITH THE PARENT AREA OF MID LEVEL CONVERGENCE/SATURATION ON THE
BACKSIDE OF THE EXITING SHORTWAVE. MEANWHILE...OFF TO THE SOUTH A
VERY NARROW BAND OF LIGHT RAIN/SPRINKLES IS MAKING ITS WAY ACROSS
PARTS OF CENTRAL KS...LIKELY DUE TO SOME SUBTLE MID LEVEL
FRONTOGENESIS IN THE ENTRANCE REGION OF A MID-UPPER JET STREAK
PULLING ACROSS NORTHERN KS/SOUTHEAST NEB.

FOLLOWING THE 05Z HRRR REFLECTIVITY CLOSELY...ALONG WITH LATEST
RADAR TRENDS...LOOKS LIKE ANY SPRINKLES IN NEB ZONES SHOULD
PRETTY MUCH BE GONE BY SUNRISE...SO WILL NOT CARRY A PRE-FIRST
PERIOD ZONE ISSUANCE TO COVER IT. AS FOR THE KS SPRINKLES...NOT
EXPECTING THESE TO BE AN ISSUE PAST SUNRISE EITHER...BUT WILL
CARRY A SLIGHT CHANCE SPRINKLE MENTION ACROSS THE FAR SOUTHERN CWA
THROUGH 12Z JUST IN CASE SOMETHING SNEAKS IN. OTHERWISE...A DRY
AND SEASONABLY PLEASANT DAY IS IN STORE. ALOFT...THE DEPARTING
SHORTWAVE AXIS WILL BE WELL UP INTO WESTERN WI BY 00Z...WITH
BROAD...MODESTLY AMPLIFIED RIDGING EXTENDING FROM THE WEST COAST
TO CENTRAL PLAINS IN ITS WAKE. AT THE SURFACE...A RIDGE AXIS WILL
GRADUALLY PASS ACROSS THE CWA THROUGH THE DAY...TRANSITIONING
WINDS FROM NORTHERLY THROUGH MUCH OF THE DAY TO MORE EASTERLY BY
DAY/S END. WITH THIS CENTER OF THIS HIGH TO THE NORTH OF THE AREA
THIS MORNING...THERE SHOULD BE AN INCREASE IN WIND SPEEDS MOST
AREAS AS BOUNDARY LAYER MIXING COMMENCES...WITH SUSTAINED SPEEDS
EASILY 10-15 MPH FOR SEVERAL HOURS...BEFORE SUBSIDING A BIT DURING
THE AFTERNOON. ALTHOUGH COULD SEE SOME LINGERING CLOUDS THIS
MORNING...AND MAYBE EVEN SOME DAYTIME FAIR WEATHER CUMULUS
DEVELOPMENT MAINLY IN EASTERN ZONES...THE CWA AS A WHOLE SHOULD
AVERAGE MOSTLY SUNNY TODAY. AS A RESULT...ANTICIPATE A FAIRLY
EFFICIENT WARM UP...AND KEPT HIGHS SIMILAR TO PREVIOUS
FORECAST...AND FAVORING THE WARMER MET GUIDANCE/RAW NAM SOLUTION
VERSUS COOLER MAV/GFS. THUS HAVE THE MAJORITY OF THE CWA REACHING
THE 72-76 RANGE.

TONIGHT...THE BROAD WESTERN TO CENTRAL CONUS RIDGE AMPLIFIES A
BIT...WITH MODEST MID LEVEL HEIGHT RISES OVER THE CENTRAL PLAINS
AS THE UPPER LEVEL FLOW BECOMES MORE NORTHERLY VERSUS WESTERLY
AROUND THE EASTERN PERIPHERY OF THE RIDGE. ALTHOUGH HAVE LEFT ALL
THUNDERSTORM MENTION OUT OF THE FORECAST FOR NOW...WILL HAVE TO KEEP
A CLOSE EYE ON FAR NORTHWEST ZONES AFTER MIDNIGHT AND ESPECIALLY
TOWARD SUNRISE...AS BOTH THE NAM/GFS ADVERTISE MODEST ELEVATED
THETA-E ADVECTION EVIDENT AT 700MB PUSHING EAST OUT OF WESTERN
NEB...ALONG WITH MAYBE UP TO A FEW HUNDRED J/KG MUCAPE ROOTED IN
THE 850-700MB LAYER. BOTH OF THESE MODELS KEEP CONVECTIVE QPF AT
LEAST SLIGHTLY NORTHWEST OF THE CWA OVER THE SANDHILLS...AND THE
00Z 4KM WRF-NMM SHOWS LITTLE HINT OF DEVELOPING CONVECTION...BUT
THIS WILL NEED CLOSELY WATCHED AS THIS KIND OF FORCING OFTEN LEADS
TO CLASSIC SUNRISE SURPRISE SHOWERS/WEAK STORMS. FOR LOW TEMPS
TONIGHT...WITH GENERALLY LIGHT EAST-SOUTHEAST BREEZES AND MOSTLY
CLEAR SKIES...OPTED TO LOWER LOWS 1-3 DEGREES FROM PREVIOUS
FORECAST...WITH MOST AREAS BETWEEN 44-48.

MONDAY...RIDGING WILL CONTINUE TO DOMINATE THE MID/UPPER
LEVELS...WITH THE AXIS GENERALLY ALIGNED ALONG THE ROCKIES...AND
CONTINUED NORTH-NORTHWEST FLOW ALOFT OVER THE CENTRAL PLAINS. AS
THE SURFACE RIDGE AXIS DEPARTS FARTHER EAST AND MODEST PRESSURE
FALLS OCCUR OVER THE HIGH PLAINS...SOUTHERLY WINDS WILL BECOME
ESTABLISHED...AND UPPED SUSTAINED SPEEDS SLIGHTLY WITH MOST OF THE
CWA SOLIDLY INTO THE 15-20 MPH RANGE MUCH OF THE DAY. DESPITE
MODEST LOW LEVEL MOISTURE RETURN WITH SURFACE DEWPOINTS POSSIBLY
APPROACHING 50 ACROSS THE WESTERN CWA...THE PRIMARY LOW LEVEL
INSTABILITY AXIS SHOULD SET UP AT LEAST 1-2 COUNTIES WEST OF THE
CWA DURING THE AFTERNOON...WITH THE NAM KEEPING ANY LATE AFTERNOON
CONVECTION SAFELY NORTHWEST OF THE AREA ACROSS THE SANDHILLS.
ASSUMING THAT NO SHOWERS/WEAK STORMS DO IN FACT DEVELOP EARLY IN
THE MORNING AS DISCUSSED ABOVE...HAVE FAIRLY HIGH CONFIDENCE IN
LEAVING STORMS OUT THROUGH THE AFTERNOON HOURS...DESPITE SPC
ASSIGNING A GENERAL THUNDER AREA TO MUCH OF THE WESTERN CWA ON THE
DAY2 OUTLOOK. WITH SOUTHERLY FLOW AND AFTERNOON MIXING TO AROUND
800MB PER NAM SOUNDINGS...KEPT HIGH TEMPS SIMILAR TO PREVIOUS
FORECAST...AND GENERALLY 2-4 DEGREES ABOVE MET/MAV GUIDANCE
CONSENSUS...WITH MOST AREAS 79-82.

MONDAY NIGHT...THE MID/UPPER RIDGE AXIS BECOMES MORE POSITIVELY
TILTED AND EXTENDS DIRECTLY THROUGH THE CENTRAL PLAINS...AS THE
RIDGE STARTS ITS EASTWARD PUSH IN RESPONSE TO AN INCOMING
SHORTWAVE AND ASSOCIATED UPPER JET STREAK MOVING INTO THE PACIFIC
NORTHWEST. ASSUMING THAT NO SANDHILLS CONVECTION SNEAKS INTO THE
CWA DURING THE EVENING...WILL STAY THE COURSE WITH A STORM-FREE
FORECAST THROUGH THE NIGHT...ALTHOUGH THIS WILL ALSO BEAR WATCHING
AS BOTH THE NAM/GFS ADVERTISE A BATCH OF ELEVATED INSTABILITY ON
THE ORDER OF 500-1000 J/KG SLIDING EAST OVER THE CWA DURING THE
NIGHT. THINKING AT THIS POINT IS THAT THESE PARCELS SHOULD REMAIN
CAPPED IN THE PRESENCE OF VERY LITTLE UPPER FORCING...WITH BETTER
CONVERGENCE ALONG THE NOSE OF THE LOW LEVEL JET AIMED MORE INTO
THE OAX CWA TOWARD THE MO RIVER...WHERE THE NAM ACTUALLY DOES
DEVELOP SOME CONVECTIVE QPF. CERTAINLY CANNOT COMPLETELY RULE OUT
A FEW SHOWERS/STORMS FLARING UP AND LATER SHIFTS MAY HAVE TO
CONSIDER ADDING A SLIGHT POP SOMEWHERE.

TUESDAY...INSTABILITY INCREASES FURTHER...AS SURFACE DEWPOINTS
CLIMB BACK INTO THE LOW-MID 50S...BUT WITH INCOMING NORTHWEST
CONUS SHORTWAVE REMAINING TO THE WEST...THIS SHOULD BE NOTHING
MORE THAN A WARM AND RATHER WINDY DAY...WITH NEAR-SURFACE PARCELS
CAPPED OFF AS SUGGESTED BY 700MB TEMPS INTO THE 11-13C RANGE. ANY
LATE AFTERNOON STORMS THAT MIGHT MANAGE TO DEVELOP IN THE REGION
SHOULD FOCUS WEST OF THE CWA NEARER THE PRIMARY SYNOPTIC DRYLINE.
AS A RESULT...EXPECT THE BIG STORY TUESDAY TO BE STRONG SOUTHERLY
WINDS...AS BOTH THE NAM/GFS DEEPEN A 989-992MB LOW OVER THE HIGH
PLAINS OVER THE COURSE OF THE DAY. THE RESULTANT STRENGTHENING
PRESSURE GRADIENT...ALONG WITH MIXING TO AT LEAST 750MB MOST
AREAS...SHOULD REALLY GET SOUTHERLY WINDS GOING. PREVIOUS FORECAST
ALREADY HAD PARTS OF THE AREA REACHING ADVISORY CRITERIA OF
SUSTAINED 30 MPH...AND GENERALLY KEPT THIS THEME INTACT...WITH THE
HIGHEST SPEEDS FOCUSED ACROSS THE WESTERN 1/2 OF THE CWA. WITH
THIS STILL BEING 5 PERIODS OUT...WAY TOO EARLY FOR A
HEADLINE...BUT WILL CONTINUE TO HIGHLIGHT IN THE HAZARDOUS WEATHER
OUTLOOK. EXPECTING MINIMAL CLOUD COVER...THIS SHOULD BE A CLASSIC
BIG WARM UP...DECENT DEWPOINT MIX-DOWN KIND OF DAY...AND HAVE
DEWPOINTS FALLING A BIT IN THE AFTERNOON...ESPECIALLY WEST. TEMP
WISE...NUDGED UP HIGHS 2-3 DEGREES FROM PREVIOUS FORECAST MOST
AREAS...AIMING FOR 89-92 MOST AREAS...AND EVEN MID 90S SOUTHWEST.
ALTHOUGH THIS IS SEVERAL DEGREES ABOVE MET/MAV GUIDANCE
CONSENSUS...IT IS MORE IN LINE WITH RAW NAM TEMPS...AND DAYS LIKE
THIS HAVE PROVEN SEVERAL TIMES IN THE PAST FEW WEEKS THAT WARMER
IS THE WAY TO GO.

TUESDAY NIGHT...YET AGAIN KEPT THE AREA FREE OF STORM
MENTION...DESPITE THE GFS TRYING TO SNEAK SOME ACTIVITY INTO
NORTHEAST ZONES AFTER MIDNIGHT. DESPITE INCREASING FORCING FROM
THE INCOMING SHORTWAVE...MOST OF THIS ENERGY WILL REMAIN BACK OVER
THE NORTHERN ROCKIES/NORTHERN PLAINS...AND BESIDES BOTH THE
NAM/GFS ADVERTISE A CONSIDERABLE CAPPING INVERSION WITH A 700MB
THERMAL RIDGE OF 13C+ SETTING UP OVER THE CWA DURING THE NIGHT.
NOT SURPRISINGLY...MODEL CONSENSUS IS TO FOCUS CONVECTION NORTH OF
THE CWA THROUGH THE NIGHT...NEAR AND JUST BEHIND AN INCOMING
SURFACE COLD FRONT AND IN AREA OF SLIGHTLY COOLER MID LEVEL TEMPS.
WILL HAVE TO IRON OUT SOME DETAILS REGARDING THE SPEED OF THIS
INCOMING COLD FRONT HOWEVER...AS BY 12Z WEDNESDAY THE NAM ALREADY
HAS THE FRONT INTO THE WESTERN CWA...WHILE THE ECMWF STILL HAS IT
BACK IN WESTERN NEB. IF ANY STORMS DO MANAGE TO DEVELOP INTO THE
NORTHERN CWA DURING THE NIGHT...STRONG TO SEVERE IS CERTAINLY
POSSIBLE...BUT CONFIDENCE STILL REMAINS LOW ENOUGH REGARDING
STORM DEVELOPMENT TO KEEP POPS BELOW THE 20 PERCENT SLIGHT CHANCE
THRESHOLD.

LONG TERM...TARTING 12Z WEDNESDAY. GUIDANCE FROM THE OPERATIONAL
GFS AND EC SUGGEST A MID LEVEL SHORT WAVE...PERHAPS A CLOSED LOW
PER THE GFS...WILL PUSH ACROSS THE NORTHERN PLAINS AND SOUTH
CENTRAL CANADA WEDNESDAY AND THURSDAY. AN ASSOCIATED SURFACE LOW
IS ALSO EXPECTED TO PUSH EAST ACROSS THE NORTHERN PLAINS AND SOUTH
CENTRAL CANADA THUS ALLOWING A LOW LEVEL BAROCLINIC ZONE TO PUSH
ACROSS OUR AREA DURING THE DAY WEDNESDAY. SURFACE RIDGING IS THEN
EXPECTED TO INFILTRATE THE CENTRAL PLAINS LATE WEDNESDAY THROUGH
EARLY FRIDAY BEFORE LOW LEVEL RETURN FLOW IS REALIZED ACROSS OUR
AREA LATE FRIDAY INTO SATURDAY.

THE OPERATIONAL GFS AND EC BOTH CONTINUE TO INDICATE CONVECTION
ALONG THE LOW LEVEL BAROCLINIC ZONE WEDNESDAY AFTERNOON AND EVENING.
THE OPERATIONAL GFS IS BECOMING SOMEWHAT MORE PROGRESSIVE AND NOW
SUGGESTS CONVECTION WILL FIRE EAST OF OUR CWA WELL AFTER THE LOW
LEVEL BAROCLINIC ZONE HAS CLEARED OUR AREA. THE EC ON THE OTHER HAND
SUGGESTS A SLIGHTLY SLOWER FROPA WITH CONVECTION POSSIBLE ALONG THE
EASTERN HALF OF OUR CWA LATE WEDNESDAY AFTERNOON INTO WEDNESDAY
EVENING. WITH 0-1KM MLCAPE VALUES PERHAPS APPROACHING 1500J/KG AND
DEEP LAYER BULK SHEAR VALUES IN THE NEIGHBORHOOD OF 40KTS...LARGE
HAIL AND PERHAPS STRONG WINDS CANNOT BE RULED OUT SHOULD
CONVECTION BE REALIZED OVER OUR AREA ALONG THE LOW LEVEL BAROCLINIC
ZONE WEDNESDAY. OPTED TO PLAY IT SAFE SINCE THE EC CONTINUES TO
SUGGEST THIS POSSIBILITY AND KEPT CONVECTION IN THE FORECAST ACROSS
THE EASTERN HALF OF THE CWA...WITH A SEVERE MENTION ALSO IN THE HWO
FOR LATE WEDNESDAY AFTERNOON INTO WEDNESDAY EVENING.

MID AND UPPER LEVEL JET ENERGY IS EXPECTED TO PUSH OVERHEAD
THE CENTRAL PLAINS LATE WEDNESDAY...WITH THE LEFT-FRONT QUAD OF A
60-70KT MID LEVEL JET STREAK EXPECTED TO SET UP SHOP OVER OUR AREA
WEDNESDAY NIGHT INTO THURSDAY MORNING. AN INDIRECT THERMAL
CIRCULATION MAY PRODUCE ENOUGH LIFT FOR PRECIPITATION
PRODUCTION...ASSUMING ENOUGH LOW TO MID LEVEL MOISTURE...AND QPF
FIELDS FROM THE OPERATIONAL GFS AND EC BOTH SUGGEST PRECIPITATION
WILL BE REALIZED WEDNESDAY NIGHT/THURSDAY MORNING. WENT AHEAD WITH
POPS LATE WEDNESDAY INTO EARLY THURSDAY AS A RESULT. THE RIGHT-REAR
QUADRANT OF THE SAME MID LEVEL JET STREAK IS THEN EXPECTED TO PUSH
OVER NORTHERN PORTIONS OF THE CWA THURSDAY NIGHT INTO FRIDAY
MORNING...THUS BRINGING ANOTHER CHANCE FOR PRECIPITATION TO NORTHERN
PORTIONS OF OUR AREA. THE INTRODUCTION OF A ~40KT LOW LEVEL JET
STREAK WILL THEN BRING FURTHER CHANCES OF PRECIPITATION TO THE AREA
FRIDAY NIGHT INTO EARLY SATURDAY. BEYOND WEDNESDAY EVENING...LOW
LEVEL MOISTURE IS NOT OVERLY IMPRESSIVE AS SURFACE RIDGING REMAINS
ENTRENCHED ACROSS THE AREA AND AS A RESULT...INSTABILITY SUFFERS
GREATLY. LOW LEVEL MOISTURE FINALLY IMPROVES BY LATE FRIDAY AS LOW
LEVEL RETURN FLOW IS REALIZED ACROSS THE AREA...WITH DEEP LAYER
MUCAPE VALUES PERHAPS CLIMBING TO AROUND 1000J/KG BY FRIDAY NIGHT.
GIVEN ALL THIS...AM NOT INCLINED TO GO WITH ANY SEVERE WORDING IN
THE HWO BEYOND WEDNESDAY EVENING.

A SUBTLE COOLING TREND SHOULD BE NOTED ACROSS THE AREA WEDNESDAY AND
THURSDAY AS SURFACE RIDGING REMAINS OVER THE AREA. LOW LEVEL RETURN
FLOW AND RESULTANT LOW LEVEL WARM AIR ADVECTION WILL THEN PROMOTE A
WARMING TREND TO FINISH OUT THE EXTENDED FORECAST PERIOD. DESPITE
ANY TRENDS...TEMPERATURES DURING THE EXTENDED FORECAST PERIOD WILL
REMAIN AT NEAR OR ABOVE-NORMAL LEVELS FOR THIS TIME OF YEAR.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

SHORT TERM...PFANNKUCH
AVIATION/LONG TERM...BRYANT





AREA FORECAST DISCUSSION

NWS HASTINGS NE

 440 AM CDT SUN MAY 20 2012

.SHORT TERM...THROUGH TUESDAY NIGHT. OFFICIALLY...THE FORECAST
REMAINS DRY THROUGH THESE 72 HOURS. HOWEVER...THIS WILL NEED
WATCHED CLOSELY AS THERE ARE AT LEAST A FEW OPPORTUNITIES FOR
THUNDERSTORMS TO POTENTIALLY SNEAK INTO THE FORECAST. OF HIGHER
CONFIDENCE IS POSSIBLE ADVISORY-CRITERIA WINDS ON TUESDAY.

08Z OBJECTIVE SURFACE ANALYSIS PLACES THE CWA BETWEEN A 1010MB LOW
OVER WESTERN IA...AND A 1021MB HIGH STRETCHED NORTH-SOUTH ACROSS
THE PANHANDLE INTO EASTERN CO. AS A RESULT...BREEZES EARLY THIS
MORNING ARE LARGELY FROM THE WEST-NORTHWEST AREA WIDE...BUT
RANGING FROM VERY LIGHT IN THE FAR WESTERN COUNTIES...TO GUSTS
STILL AROUND 20 MPH IN THE EAST WHERE THE GRADIENT REMAINS
TIGHTEST. WATER VAPOR IMAGERY CLEARLY DEPICTS THE DEPARTING
SHORTWAVE RESPONSIBLE FOR YESTERDAY/S ROUND OF SEVERE WEATHER NOW
OVER NORTHEAST NEB...WITH BROAD QUASI-ZONAL FLOW ALOFT EXTENDING
BACK UPSTREAM TO THE EASTERN PACIFIC. RADAR AND 11-3.9 MICRON
SATELLITE IMAGERY CONFIRMS A STUBBORN AREA OF LINGERING LIGHT RAIN
THAT HAS FINALLY PUSHED OUT OF THE NORTHEASTERN CWA...IN ASSOCIATION
WITH THE PARENT AREA OF MID LEVEL CONVERGENCE/SATURATION ON THE
BACKSIDE OF THE EXITING SHORTWAVE. MEANWHILE...OFF TO THE SOUTH A
VERY NARROW BAND OF LIGHT RAIN/SPRINKLES IS MAKING ITS WAY ACROSS
PARTS OF CENTRAL KS...LIKELY DUE TO SOME SUBTLE MID LEVEL
FRONTOGENESIS IN THE ENTRANCE REGION OF A MID-UPPER JET STREAK
PULLING ACROSS NORTHERN KS/SOUTHEAST NEB.

FOLLOWING THE 05Z HRRR REFLECTIVITY CLOSELY...ALONG WITH LATEST
RADAR TRENDS...LOOKS LIKE ANY SPRINKLES IN NEB ZONES SHOULD
PRETTY MUCH BE GONE BY SUNRISE...SO WILL NOT CARRY A PRE-FIRST
PERIOD ZONE ISSUANCE TO COVER IT. AS FOR THE KS SPRINKLES...NOT
EXPECTING THESE TO BE AN ISSUE PAST SUNRISE EITHER...BUT WILL
CARRY A SLIGHT CHANCE SPRINKLE MENTION ACROSS THE FAR SOUTHERN CWA
THROUGH 12Z JUST IN CASE SOMETHING SNEAKS IN. OTHERWISE...A DRY
AND SEASONABLY PLEASANT DAY IS IN STORE. ALOFT...THE DEPARTING
SHORTWAVE AXIS WILL BE WELL UP INTO WESTERN WI BY 00Z...WITH
BROAD...MODESTLY AMPLIFIED RIDGING EXTENDING FROM THE WEST COAST
TO CENTRAL PLAINS IN ITS WAKE. AT THE SURFACE...A RIDGE AXIS WILL
GRADUALLY PASS ACROSS THE CWA THROUGH THE DAY...TRANSITIONING
WINDS FROM NORTHERLY THROUGH MUCH OF THE DAY TO MORE EASTERLY BY
DAY/S END. WITH THIS CENTER OF THIS HIGH TO THE NORTH OF THE AREA
THIS MORNING...THERE SHOULD BE AN INCREASE IN WIND SPEEDS MOST
AREAS AS BOUNDARY LAYER MIXING COMMENCES...WITH SUSTAINED SPEEDS
EASILY 10-15 MPH FOR SEVERAL HOURS...BEFORE SUBSIDING A BIT DURING
THE AFTERNOON. ALTHOUGH COULD SEE SOME LINGERING CLOUDS THIS
MORNING...AND MAYBE EVEN SOME DAYTIME FAIR WEATHER CUMULUS
DEVELOPMENT MAINLY IN EASTERN ZONES...THE CWA AS A WHOLE SHOULD
AVERAGE MOSTLY SUNNY TODAY. AS A RESULT...ANTICIPATE A FAIRLY
EFFICIENT WARM UP...AND KEPT HIGHS SIMILAR TO PREVIOUS
FORECAST...AND FAVORING THE WARMER MET GUIDANCE/RAW NAM SOLUTION
VERSUS COOLER MAV/GFS. THUS HAVE THE MAJORITY OF THE CWA REACHING
THE 72-76 RANGE.

TONIGHT...THE BROAD WESTERN TO CENTRAL CONUS RIDGE AMPLIFIES A
BIT...WITH MODEST MID LEVEL HEIGHT RISES OVER THE CENTRAL PLAINS
AS THE UPPER LEVEL FLOW BECOMES MORE NORTHERLY VERSUS WESTERLY
AROUND THE EASTERN PERIPHERY OF THE RIDGE. ALTHOUGH HAVE LEFT ALL
THUNDERSTORM MENTION OUT OF THE FORECAST FOR NOW...WILL HAVE TO KEEP
A CLOSE EYE ON FAR NORTHWEST ZONES AFTER MIDNIGHT AND ESPECIALLY
TOWARD SUNRISE...AS BOTH THE NAM/GFS ADVERTISE MODEST ELEVATED
THETA-E ADVECTION EVIDENT AT 700MB PUSHING EAST OUT OF WESTERN
NEB...ALONG WITH MAYBE UP TO A FEW HUNDRED J/KG MUCAPE ROOTED IN
THE 850-700MB LAYER. BOTH OF THESE MODELS KEEP CONVECTIVE QPF AT
LEAST SLIGHTLY NORTHWEST OF THE CWA OVER THE SANDHILLS...AND THE
00Z 4KM WRF-NMM SHOWS LITTLE HINT OF DEVELOPING CONVECTION...BUT
THIS WILL NEED CLOSELY WATCHED AS THIS KIND OF FORCING OFTEN LEADS
TO CLASSIC SUNRISE SURPRISE SHOWERS/WEAK STORMS. FOR LOW TEMPS
TONIGHT...WITH GENERALLY LIGHT EAST-SOUTHEAST BREEZES AND MOSTLY
CLEAR SKIES...OPTED TO LOWER LOWS 1-3 DEGREES FROM PREVIOUS
FORECAST...WITH MOST AREAS BETWEEN 44-48.

MONDAY...RIDGING WILL CONTINUE TO DOMINATE THE MID/UPPER
LEVELS...WITH THE AXIS GENERALLY ALIGNED ALONG THE ROCKIES...AND
CONTINUED NORTH-NORTHWEST FLOW ALOFT OVER THE CENTRAL PLAINS. AS
THE SURFACE RIDGE AXIS DEPARTS FARTHER EAST AND MODEST PRESSURE
FALLS OCCUR OVER THE HIGH PLAINS...SOUTHERLY WINDS WILL BECOME
ESTABLISHED...AND UPPED SUSTAINED SPEEDS SLIGHTLY WITH MOST OF THE
CWA SOLIDLY INTO THE 15-20 MPH RANGE MUCH OF THE DAY. DESPITE
MODEST LOW LEVEL MOISTURE RETURN WITH SURFACE DEWPOINTS POSSIBLY
APPROACHING 50 ACROSS THE WESTERN CWA...THE PRIMARY LOW LEVEL
INSTABILITY AXIS SHOULD SET UP AT LEAST 1-2 COUNTIES WEST OF THE
CWA DURING THE AFTERNOON...WITH THE NAM KEEPING ANY LATE AFTERNOON
CONVECTION SAFELY NORTHWEST OF THE AREA ACROSS THE SANDHILLS.
ASSUMING THAT NO SHOWERS/WEAK STORMS DO IN FACT DEVELOP EARLY IN
THE MORNING AS DISCUSSED ABOVE...HAVE FAIRLY HIGH CONFIDENCE IN
LEAVING STORMS OUT THROUGH THE AFTERNOON HOURS...DESPITE SPC
ASSIGNING A GENERAL THUNDER AREA TO MUCH OF THE WESTERN CWA ON THE
DAY2 OUTLOOK. WITH SOUTHERLY FLOW AND AFTERNOON MIXING TO AROUND
800MB PER NAM SOUNDINGS...KEPT HIGH TEMPS SIMILAR TO PREVIOUS
FORECAST...AND GENERALLY 2-4 DEGREES ABOVE MET/MAV GUIDANCE
CONSENSUS...WITH MOST AREAS 79-82.

MONDAY NIGHT...THE MID/UPPER RIDGE AXIS BECOMES MORE POSITIVELY
TILTED AND EXTENDS DIRECTLY THROUGH THE CENTRAL PLAINS...AS THE
RIDGE STARTS ITS EASTWARD PUSH IN RESPONSE TO AN INCOMING
SHORTWAVE AND ASSOCIATED UPPER JET STREAK MOVING INTO THE PACIFIC
NORTHWEST. ASSUMING THAT NO SANDHILLS CONVECTION SNEAKS INTO THE
CWA DURING THE EVENING...WILL STAY THE COURSE WITH A STORM-FREE
FORECAST THROUGH THE NIGHT...ALTHOUGH THIS WILL ALSO BEAR WATCHING
AS BOTH THE NAM/GFS ADVERTISE A BATCH OF ELEVATED INSTABILITY ON
THE ORDER OF 500-1000 J/KG SLIDING EAST OVER THE CWA DURING THE
NIGHT. THINKING AT THIS POINT IS THAT THESE PARCELS SHOULD REMAIN
CAPPED IN THE PRESENCE OF VERY LITTLE UPPER FORCING...WITH BETTER
CONVERGENCE ALONG THE NOSE OF THE LOW LEVEL JET AIMED MORE INTO
THE OAX CWA TOWARD THE MO RIVER...WHERE THE NAM ACTUALLY DOES
DEVELOP SOME CONVECTIVE QPF. CERTAINLY CANNOT COMPLETELY RULE OUT
A FEW SHOWERS/STORMS FLARING UP AND LATER SHIFTS MAY HAVE TO
CONSIDER ADDING A SLIGHT POP SOMEWHERE.

TUESDAY...INSTABILITY INCREASES FURTHER...AS SURFACE DEWPOINTS
CLIMB BACK INTO THE LOW-MID 50S...BUT WITH INCOMING NORTHWEST
CONUS SHORTWAVE REMAINING TO THE WEST...THIS SHOULD BE NOTHING
MORE THAN A WARM AND RATHER WINDY DAY...WITH NEAR-SURFACE PARCELS
CAPPED OFF AS SUGGESTED BY 700MB TEMPS INTO THE 11-13C RANGE. ANY
LATE AFTERNOON STORMS THAT MIGHT MANAGE TO DEVELOP IN THE REGION
SHOULD FOCUS WEST OF THE CWA NEARER THE PRIMARY SYNOPTIC DRYLINE.
AS A RESULT...EXPECT THE BIG STORY TUESDAY TO BE STRONG SOUTHERLY
WINDS...AS BOTH THE NAM/GFS DEEPEN A 989-992MB LOW OVER THE HIGH
PLAINS OVER THE COURSE OF THE DAY. THE RESULTANT STRENGTHENING
PRESSURE GRADIENT...ALONG WITH MIXING TO AT LEAST 750MB MOST
AREAS...SHOULD REALLY GET SOUTHERLY WINDS GOING. PREVIOUS FORECAST
ALREADY HAD PARTS OF THE AREA REACHING ADVISORY CRITERIA OF
SUSTAINED 30 MPH...AND GENERALLY KEPT THIS THEME INTACT...WITH THE
HIGHEST SPEEDS FOCUSED ACROSS THE WESTERN 1/2 OF THE CWA. WITH
THIS STILL BEING 5 PERIODS OUT...WAY TOO EARLY FOR A
HEADLINE...BUT WILL CONTINUE TO HIGHLIGHT IN THE HAZARDOUS WEATHER
OUTLOOK. EXPECTING MINIMAL CLOUD COVER...THIS SHOULD BE A CLASSIC
BIG WARM UP...DECENT DEWPOINT MIX-DOWN KIND OF DAY...AND HAVE
DEWPOINTS FALLING A BIT IN THE AFTERNOON...ESPECIALLY WEST. TEMP
WISE...NUDGED UP HIGHS 2-3 DEGREES FROM PREVIOUS FORECAST MOST
AREAS...AIMING FOR 89-92 MOST AREAS...AND EVEN MID 90S SOUTHWEST.
ALTHOUGH THIS IS SEVERAL DEGREES ABOVE MET/MAV GUIDANCE
CONSENSUS...IT IS MORE IN LINE WITH RAW NAM TEMPS...AND DAYS LIKE
THIS HAVE PROVEN SEVERAL TIMES IN THE PAST FEW WEEKS THAT WARMER
IS THE WAY TO GO.

TUESDAY NIGHT...YET AGAIN KEPT THE AREA FREE OF STORM
MENTION...DESPITE THE GFS TRYING TO SNEAK SOME ACTIVITY INTO
NORTHEAST ZONES AFTER MIDNIGHT. DESPITE INCREASING FORCING FROM
THE INCOMING SHORTWAVE...MOST OF THIS ENERGY WILL REMAIN BACK OVER
THE NORTHERN ROCKIES/NORTHERN PLAINS...AND BESIDES BOTH THE
NAM/GFS ADVERTISE A CONSIDERABLE CAPPING INVERSION WITH A 700MB
THERMAL RIDGE OF 13C+ SETTING UP OVER THE CWA DURING THE NIGHT.
NOT SURPRISINGLY...MODEL CONSENSUS IS TO FOCUS CONVECTION NORTH OF
THE CWA THROUGH THE NIGHT...NEAR AND JUST BEHIND AN INCOMING
SURFACE COLD FRONT AND IN AREA OF SLIGHTLY COOLER MID LEVEL TEMPS.
WILL HAVE TO IRON OUT SOME DETAILS REGARDING THE SPEED OF THIS
INCOMING COLD FRONT HOWEVER...AS BY 12Z WEDNESDAY THE NAM ALREADY
HAS THE FRONT INTO THE WESTERN CWA...WHILE THE ECMWF STILL HAS IT
BACK IN WESTERN NEB. IF ANY STORMS DO MANAGE TO DEVELOP INTO THE
NORTHERN CWA DURING THE NIGHT...STRONG TO SEVERE IS CERTAINLY
POSSIBLE...BUT CONFIDENCE STILL REMAINS LOW ENOUGH REGARDING
STORM DEVELOPMENT TO KEEP POPS BELOW THE 20 PERCENT SLIGHT CHANCE
THRESHOLD.

.LONG TERM...TARTING 12Z WEDNESDAY. GUIDANCE FROM THE OPERATIONAL
GFS AND EC SUGGEST A MID LEVEL SHORT WAVE...PERHAPS A CLOSED LOW
PER THE GFS...WILL PUSH ACROSS THE NORTHERN PLAINS AND SOUTH
CENTRAL CANADA WEDNESDAY AND THURSDAY. AN ASSOCIATED SURFACE LOW
IS ALSO EXPECTED TO PUSH EAST ACROSS THE NORTHERN PLAINS AND SOUTH
CENTRAL CANADA THUS ALLOWING A LOW LEVEL BAROCLINIC ZONE TO PUSH
ACROSS OUR AREA DURING THE DAY WEDNESDAY. SURFACE RIDGING IS THEN
EXPECTED TO INFILTRATE THE CENTRAL PLAINS LATE WEDNESDAY THROUGH
EARLY FRIDAY BEFORE LOW LEVEL RETURN FLOW IS REALIZED ACROSS OUR
AREA LATE FRIDAY INTO SATURDAY.

THE OPERATIONAL GFS AND EC BOTH CONTINUE TO INDICATE CONVECTION
ALONG THE LOW LEVEL BAROCLINIC ZONE WEDNESDAY AFTERNOON AND EVENING.
THE OPERATIONAL GFS IS BECOMING SOMEWHAT MORE PROGRESSIVE AND NOW
SUGGESTS CONVECTION WILL FIRE EAST OF OUR CWA WELL AFTER THE LOW
LEVEL BAROCLINIC ZONE HAS CLEARED OUR AREA. THE EC ON THE OTHER HAND
SUGGESTS A SLIGHTLY SLOWER FROPA WITH CONVECTION POSSIBLE ALONG THE
EASTERN HALF OF OUR CWA LATE WEDNESDAY AFTERNOON INTO WEDNESDAY
EVENING. WITH 0-1KM MLCAPE VALUES PERHAPS APPROACHING 1500J/KG AND
DEEP LAYER BULK SHEAR VALUES IN THE NEIGHBORHOOD OF 40KTS...LARGE
HAIL AND PERHAPS STRONG WINDS CANNOT BE RULED OUT SHOULD
CONVECTION BE REALIZED OVER OUR AREA ALONG THE LOW LEVEL BAROCLINIC
ZONE WEDNESDAY. OPTED TO PLAY IT SAFE SINCE THE EC CONTINUES TO
SUGGEST THIS POSSIBILITY AND KEPT CONVECTION IN THE FORECAST ACROSS
THE EASTERN HALF OF THE CWA...WITH A SEVERE MENTION ALSO IN THE HWO
FOR LATE WEDNESDAY AFTERNOON INTO WEDNESDAY EVENING.

MID AND UPPER LEVEL JET ENERGY IS EXPECTED TO PUSH OVERHEAD
THE CENTRAL PLAINS LATE WEDNESDAY...WITH THE LEFT-FRONT QUAD OF A
60-70KT MID LEVEL JET STREAK EXPECTED TO SET UP SHOP OVER OUR AREA
WEDNESDAY NIGHT INTO THURSDAY MORNING. AN INDIRECT THERMAL
CIRCULATION MAY PRODUCE ENOUGH LIFT FOR PRECIPITATION
PRODUCTION...ASSUMING ENOUGH LOW TO MID LEVEL MOISTURE...AND QPF
FIELDS FROM THE OPERATIONAL GFS AND EC BOTH SUGGEST PRECIPITATION
WILL BE REALIZED WEDNESDAY NIGHT/THURSDAY MORNING. WENT AHEAD WITH
POPS LATE WEDNESDAY INTO EARLY THURSDAY AS A RESULT. THE RIGHT-REAR
QUADRANT OF THE SAME MID LEVEL JET STREAK IS THEN EXPECTED TO PUSH
OVER NORTHERN PORTIONS OF THE CWA THURSDAY NIGHT INTO FRIDAY
MORNING...THUS BRINGING ANOTHER CHANCE FOR PRECIPITATION TO NORTHERN
PORTIONS OF OUR AREA. THE INTRODUCTION OF A ~40KT LOW LEVEL JET
STREAK WILL THEN BRING FURTHER CHANCES OF PRECIPITATION TO THE AREA
FRIDAY NIGHT INTO EARLY SATURDAY. BEYOND WEDNESDAY EVENING...LOW
LEVEL MOISTURE IS NOT OVERLY IMPRESSIVE AS SURFACE RIDGING REMAINS
ENTRENCHED ACROSS THE AREA AND AS A RESULT...INSTABILITY SUFFERS
GREATLY. LOW LEVEL MOISTURE FINALLY IMPROVES BY LATE FRIDAY AS LOW
LEVEL RETURN FLOW IS REALIZED ACROSS THE AREA...WITH DEEP LAYER
MUCAPE VALUES PERHAPS CLIMBING TO AROUND 1000J/KG BY FRIDAY NIGHT.
GIVEN ALL THIS...AM NOT INCLINED TO GO WITH ANY SEVERE WORDING IN
THE HWO BEYOND WEDNESDAY EVENING.

A SUBTLE COOLING TREND SHOULD BE NOTED ACROSS THE AREA WEDNESDAY AND
THURSDAY AS SURFACE RIDGING REMAINS OVER THE AREA. LOW LEVEL RETURN
FLOW AND RESULTANT LOW LEVEL WARM AIR ADVECTION WILL THEN PROMOTE A
WARMING TREND TO FINISH OUT THE EXTENDED FORECAST PERIOD. DESPITE
ANY TRENDS...TEMPERATURES DURING THE EXTENDED FORECAST PERIOD WILL
REMAIN AT NEAR OR ABOVE-NORMAL LEVELS FOR THIS TIME OF YEAR.

&&

.PREV DISCUSSION... /ISSUED 1044 PM CDT SAT MAY 19 2012/

AVIATION...06Z KGRI TAF.  MAY START OFF WITH MVFR CONDITIONS AS
LOWER CLOUDS JUST TO THE WEST WRAPPING AROUND MID LEVEL
CIRCULATION CURRENTLY OVERHEAD AND MOVING ENE. CLEAR SLOT SOUTH
WILL BE CLOSE AND WILL NEED TO MONITOR...AS WE SHOULD EVENTUALLY
BECOME VFR AND HOW QUICKLY DEPENDS ON EXTENT OF WRAP AROUND
CLOUDS. SHOULD SEE CLEAR SKIES FOR MOST OF THE DAYTIME AND
EVENING ON SUNDAY AS SURFACE HIGH PRESSURE MOVES EAST OVER THE
AREA WITH MUCH DRIER AIR AND SUBSIDENCE ALOFT. THIS WILL ALLOW
WINDS TO BE A LITTLE LIGHTER ON SUNDAY STARTING OUT FROM THE
NORTH...THEN NORTHEAST AND EVENTUALLY EASTERLY.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

SHORT TERM...PFANNKUCH
LONG TERM...BRYANT






AREA FORECAST DISCUSSION

NWS WILMINGTON NC

 800 PM EDT MON MAY 21 2012

.SYNOPSIS...
TROPICAL STORM ALBERTO WILL ACCELERATE OUT TO THE NORTHEAST TONIGHT
AND TUESDAY...REMAINING TOO FAR FROM LAND FOR ANY DIRECT IMPACTS. A
WEAK COLD FRONT WILL STALL NEAR OR WEST OF THE AREA TUESDAY NIGHT
AND WILL DISSIPATE WEDNESDAY OR THURSDAY. HIGH PRESSURE WILL DEVELOP
ACROSS THE WESTERN ATLANTIC LATE IN THE WEEK AND CONTINUE THROUGH
THE WEEKEND...BRINGING WARMER WEATHER.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 745 PM MONDAY...ACROSS THE ILM CWA...THE PRESSURE PATTERN
REMAINS SOMEWHAT DISORGANIZED ALONG WITH A RELAXED SFC PRESSURE
GRADIENT. THE FA HAS BEEN CAUGHT UP IN A WEB THIS WEEKEND INTO TODAY
FROM ANY 1 OF THE 3 DISCRETE LOW PRESSURE CENTERS SURROUND US.
1 TO THE SOUTH SOUTHEAST...NORTHEAST...AND NORTHWEST. THE LOW TO
THE SOUTH IS TROPICAL STORM ALBERTO. THE LOW TO THE NORTHEAST IS
ASSOCIATED WITH A WEAK UPPER LOW THAT HAD BEEN SITTING OFF THE VA-NC
COASTS OF THE PAST FEW DAYS. THIS CIRCULATION FROM THIS LOW BROUGHT
IN MOISTURE IN THE LOWER LEVELS THIS PAST WEEKEND. THE LOW TO THE
NORTHWEST IS ASSOCIATED WITH AN UPPER TROUGH SLIDING EAST SOUTHEAST
ACROSS KENTUCKY AND TENNESSEE AT THE MOMENT. ALBERTO AND THE LOW TO
THE NORTHEAST POSE LITTLE IF ANY ADDITIONAL DIRECT IMPACT TO THE
AREA AS THEY BOTH PUSH OUT TO SEA. THE LOW TO OUR NORTHWEST WILL
MOVE INTO THE CENTRAL CAROLINAS AND VIRGINIA BY SUNRISE TUESDAY AS
THE ASSOCIATED UPPER TROUGH APPROACHES.

THE DIURNALLY DRIVEN ISOLATED CONVECTION THIS EVENING IS NEARLY
OVERWITH...AND SHOULD BE A MEMORY AN HOUR OR SO AFTER SUNSET. THIS
WILL LEAVE A MOSTLY CLEAR SKY FOR THE OVERNIGHT...WITH SOME INCREASE
OF MOISTURE WEST OF THE I-95 CORRIDOR TOWARDS TUESDAY DAYBREAK. HAVE
KEPT POPS NULL AND VOID FROM MID TO LATE THIS EVENING UNTIL THE
START OF THE SHORT TERM WHEN LIFT AHEAD OF THE COLD FRONT BECOMES
APPARENT. .

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
AS OF 3 PM MONDAY...UNSETTLED WEATHER THROUGH THE PERIOD AS AN
UPPER TROUGH DROPS IN FROM THE NORTHWEST TUE THEN BECOMES
SEMI-CUTOFF OVER THE AREA WED. LOOKS LIKE BOTH TUE AND WED WILL BE
ACTIVE AS FAR AS CONVECTION IS CONCERNED. HIGH WILL BE SIMILAR BOTH
DAYS...LOW TO MID 80S...WITH DEWPOINT IN THE LOW TO MID 60S. UPPER
TROUGH/LOW AND ASSOCIATED COLD AIR ALOFT COMBINED WITH DIURNAL
HEATING...60 DEGREE DEWPOINTS...CONVERGENCE ALONG THE SEABREEZE WILL
PRODUCE CONVECTION EACH DAY. COVERAGE WISE WED HAD LOOKED A LITTLE
MORE FAVORABLE BUT LATEST GUIDANCE HAS BACKED OFF A BIT ON THE
DEEPER MOISTURE. NOW BOTH DAYS APPEAR SIMILAR WITH RESPECT TO BOTH
PRECIP COVERAGE AND INTENSITY...CARRYING 40-50 POP BOTH DAYS. SBCAPE
VALUES ARE IN THE 1000-1500 J/KG RANGE WITH VERTICAL PROFILES
SUGGESTING A FEW STRONG TO POTENTIALLY SEVERE PULSE STORMS COULD
DEVELOP. SPC MAINTAINS THE SEE TEXT FOR TUE AND WITH A SIMILAR
ENVIRONMENT EXPECTED ON WED WOULD NOT BE SHOCKED IF A SEE TEXT WERE
ISSUED FOR WED AT SOME POINT...ESPECIALLY WITH THE COLDEST CORE
ALOFT DIRECTLY OVERHEAD...THOUGH IT WILL BE MODIFYING. PREVIOUS
FORECAST CARRIED CHANCE POP FOR TUE NIGHT...AND GIVEN THE UPPER
TROUGH/LOW OVERHEAD WOULD EXPECT CONVECTION TO CONTINUE INTO THE
EARLY MORNING HOURS. WED NIGHT THINGS START TO DRY OUT AS THE UPPER
LOW LIFTS NORTH AND DRIER AIR STARTS TO INFILTRATE FROM THE
SOUTHWEST. OVERNIGHT LOWS WILL RUN IN THE LOW TO MID 60S.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...THE SOUTHERLY RETURN FLOW INITIALLY AROUND
BERMUDA HIGH WILL BE REPLACED BY A NORTHEAST FLOW AS HIGH PRESSURE
RIDGES DOWN FROM CANADA BY SAT. OVERALL THE SURFACE FLOW WILL BE
DOMINATED MORE BY LAND/SEA BREEZE THROUGH MOST OF THE LONG TERM AS
PRESSURE PATTERN REMAINS WEAK. EXPECT DEEP S-SW FLOW RETURN FLOW ON
THURS AS MID TO UPPER TROUGH CONTINUES TO DIG DOWN TO OUR WEST AND
BERMUDA HIGH RIDGES IN FROM THE ATLANTIC. THE H5 TROUGH AXIS SHOULD
MOVE OFF SHORE THURS NIGHT WITH A DEEPER NE FLOW DEVELOPING AS UPPER
RIDGE BUILDS INTO THE CAROLINAS FROM THE WEST THROUGH THE WEEKEND.
ENERGY FROM THIS H5 SHORTWAVE MAY PROVIDE SOME ENHANCEMENT TO
LOCALIZED CONVECTION THURS AFTERNOON BUT WE WILL ACTUALLY GET SOME
DRIER AIR MOVING IN FROM THE SW IN THE MID LEVELS COMING AROUND THE
BASE OF THE TROUGH ON THURS. THIS SHOULD HELP TO INHIBIT ANY STRONG
CONVECTION BUT WILL KEEP ISOLATED SHWRS IN THE FORECAST MAINLY LATE
DAY THURS INTO THURS NIGHT BEFORE SHORTWAVE LIFTS OFF TO THE
NORTHEAST. EXPECT PLENTY OF SUBSIDENCE ON BACK END OF TROUGH AS
RIDGE BUILDS IN LATE FRI THROUGH THE WEEKEND. HEIGHTS INCREASE CLOSE
TO 590 DEM OVER THE WEEKEND AS RIDGE BUILDS TO OUR WEST. OVERALL
EXPECT ONLY LOCALIZED CONVECTION POSSIBLE ALONG SEA BREEZE WITH A
SUMMER-LIKE AIR MASS IN PLACE. DEWPOINTS WILL BE IN THE MID 60S
THROUGH THE WEEKEND. A WAVE OF LOW PRESSURE MAY MOVE INTO THE
CAROLINAS SUN NIGHT INTO MONDAY WHICH MAY PRODUCE A BETTER CHC OF
PCP TOWARD THE END OF THE MEMORIAL DAY WEEKEND WITH A STRONGER ON
SHORE FLOW.

TEMPS SHOULD RUN ABOVE NORMAL THROUGH THE EXTENDED PERIOD AS RIDGE
BUILDS AND HEIGHTS RISE. EXPECT LESS OF A DIURNAL TREND AS A MORE
HUMID AIR MASS WILL REMAIN IN PLACE. OVERALL 80S DURING THE DAY AND
60S AT NIGHT. TEMPS SHOULD BE HIGHEST ON SUNDAY AS HEIGHTS PEAK OVER
LOCAL AREA NEAR 590 DEM.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
AS OF 00Z...EXPECT VFR THROUGH THE OVERNIGHT HOURS...WITH PATCHY
DENSE FOG CREATING MVFR/POTENTIAL IFR LATE OVERNIGHT INTO THE EARLY
MORNING HOURS. VFR WILL PREVAIL BY MORNING...WITH POTENTIAL FOR
BRIEF MVFR IN AFTERNOON VCSH/VCTS.

LATEST RADAR IMAGERY DEPICTS LINGERING ISOLATED RAIN SHOWERS
CONTINUING TO DISSIPATE...WITH A WELL-DEFINED SEABREEZE PROPAGATING
WELL INLAND. FEW/SCT MID TO HIGH LEVEL CLOUDS WILL CONTINUE THROUGH
THE OVERNIGHT HOURS...WITH LIGHT AND VARIABLE WINDS. GIVEN
AVAILABLE LOW LEVEL MOISTURE...LIGHT WINDS AND SOMEWHAT MODERATE
RADIATIONAL COOLING CONDITIONS...EXPECT PATCHY DENSE FOG LATE
OVERNIGHT INTO THE EARLY MORNING HOURS. FOR NOW HAVE KEPT
RESTRICTIONS AT MVFR...BUT CANNOT RULE OUT VISIBILITIES BEING
REDUCED EVEN MORE CREATING IFR CONDITIONS...ESPECIALLY ALONG THE
COAST. AFTER DAYBREAK...ANY LINGERING FOG WILL QUICKLY BURN OFF
ALLOWING FOR VFR TO PREVAIL WITH LIGHT WEST WINDS...GRADUALLY BACKING
TO THE SOUTH- SOUTHWEST. BY THE AFTERNOON HOURS...SUSTAINED WINDS
WILL BE AOB 12 KTS. FOR LATE MORNING THROUGH THE END OF THE VALID
PERIOD...WILL HAVE CHANCE FOR ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS. FOR NOW HAVE KEPT IN VCSH. CANNOT RULE OUT BRIEF
MVFR IN HEAVIER DOWNPOURS.

EXTENDED OUTLOOK...SCATTERED SHOWERS CREATING MVFR...WITH ISOLATED
THUNDERSTORMS CREATING TEMPO IFR POSSIBLE THROUGH THE EXTENDED
PERIOD.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 730 PM MONDAY...TROPICAL STORM ALBERTO IS ON THE MOVE...BUT
FORTUNATELY TOWARD THE EAST NORTHEAST TAKING IT WELL OFFSHORE FROM
THE SOUTHEAST U.S. COAST TONIGHT THROUGH TUESDAY. THE VORTEX OF
WINDS AROUND ALBERTO IS QUITE SMALL AND SHOULD COMPLETELY BYPASS THE
ILM WATERS. LATEST HRRR HOWEVER IS QUITE ENTHUSIASTIC WITH ITS
CLOSER APPROACH OF ALBERTO BUT CONSENSUS AMONGST THE MODELS HAVE IT
GOING OUT TO SEA. LOOK FOR VEERING WIND DIRECTIONS FROM NE TO WEST
NORTHWEST BY DAYBREAK TUESDAY. SPEEDS GENERALLY UNDER 10 KT.

SIGNIFICANT SEAS WILL RUN AROUND 3 FT THIS EVENING. WAVEWATCH3 AND
SWAN INDICATE AN ESE..3 TO 5 FT WAVE TRAIN WITH PERIODS 9-10 SECONDS
WILL AFFECT THE ILM WATERS DURING THE PRE-DAWN HOURS OF TUESDAY AND
THERE-AFTER. WILL INDICATE CURRENT SIGNIFICANT SEAS 2 TO AROUND 3
FT...BUILDING TO 3 TO 4 FT OVERNIGHT INTO TUESDAY. THE SHOALS NEAR
THE OUTER WATERS OFF CAPE FEAR COULD OBSERVE 5 FOOTERS PRIOR TO THIS
WAVE TRAIN CROSSING IT. AND OF COURSE THE SHADOW CREATED BY FPS WITH
AN EAST SOUTHEAST SWELL...WILL KEEP SEAS CLOSER TO 2 FT ACROSS THE
WATERS OFF BRUNSWICK COUNTY.

SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 2 PM MONDAY...SOUTH TO SOUTHWEST FLOW WILL DOMINATE THE
PERIOD. ALTHOUGH ALBERTO WILL PASS EAST OF THE WATERS THE STORM WILL
BE IN SUCH A WEAKENED STATE AND FAR ENOUGH EAST THAT IT WILL NOT
DIRECTLY IMPACT THE REGION. SOME WEAK SWELL FROM THE STORM MAY
AFFECT THE WATERS TUE INTO WED BUT OTHERWISE THERE WILL BE NO HINT
OF THE STORM. SPEEDS WILL BE 10 TO 15 KT FOR THE MAJORITY OF THE
PERIOD...SLIGHTLY LESS AT NIGHT...WITH SOME NEAR SHORE ENHANCEMENT
EACH DAY AS THE SEABREEZE DEVELOPS. SEAS WILL BE A COMBINATION OF
SOUTHERLY WIND WAVE AND SOUTHEAST TO EAST ALBERTO SWELL...RUNNING 3
TO 4 FT BOTH TUE AND WED.

LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 3 PM MONDAY...SOUTHERLY RETURN FLOW ON THURS AROUND BERMUDA
HIGH WILL BE REPLACED BY A N-NE FLOW THROUGH LATE FRI AS HIGH
PRESSURE BUILDS DOWN FROM CANADA. WINDS NEAR SHORE WILL BE DRIVEN
BY LAND/SEA BREEZE AS OVERALL PRESSURE PATTERN REMAINS MORE ON THE
WEAK SIDE. WINDS GENERALLY LESS THAN 15 KTS THURS AND FRI MAY
INCREASE THROUGH THE LATTER HALF OF THE WEEKEND AS A WAVE OF LOW
PRESSURE MOVES WESTWARD FROM THE OFF SHORE ATLANTIC WATERS TOWARD
THE LOCAL WATERS.

SEAS WILL BE REMAIN 2 TO 3 FT THROUGH MOST OF THE PERIOD BUT MAY
INCREASE WITH A STRONG ON SHORE PUSH BY LATE IN THE WEEKEND AS WAVE
OF LOW PRESSURE MIGRATES WESTWARD TOWARD LOCAL WATERS. SEAS WILL MIX
WITH A DECREASING EASTERLY SWELL AROUND 9 SECONDS ON THURS.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...DCH/TRA
SHORT TERM...III
LONG TERM...RGZ
AVIATION...MRR










AREA FORECAST DISCUSSION

NWS GRAND FORKS ND

 328 AM CDT SUN MAY 20 2012

.SHORT TERM (TODAY-TUESDAY NIGHT)...CHALLENGE WILL BE NEAR TERM
SHOWERS ACROSS THE SOUTHEAST AND THEN PRECIP CHANCES MONDAY
AFTERNOON INTO TUESDAY NIGHT. 00Z MODELS IN DECENT AGREEMENT AND
WILL FOLLOW A BLEND FOR DETAILS. WILL USE ECMWF/NAM FOR LOW-LEVEL
MOISTURE AS GFS IS LIKELY TOO MOIST.

UPPER WAVE AND ASSOCIATED SHOWERS MAY LINGER ACROSS THE EXTREME SE
FA EARLY THIS MORNING...BUT SHOULD MOVE EAST BY 15Z. CURRENTLY...LOW-
LEVEL DRY AIR COMBINED WITH WEAKENING SHOWERS ACROSS THE FAR SE FA
ARE CREATING GUSTY WINDS 30-50 MPH. THESE GUSTY WINDS SHOULD BE
SHORT LIVED...AND ISSUED A SPS TO MENTION THE POSSIBILITY.
OTHERWISE...SURFACE RIDGING WILL MOVE INTO THE REGION TODAY. THERE
WILL BE AN UPPER LEVEL COLD POOL AND LIKELY AFTERNOON CU
DEVELOPMENT...BUT LARGE SCALE SUBSIDENCE SHOULD LIMIT COVERAGE TO
SCATTERED. THINKING THERE WILL BE ENOUGH SOLAR FOR MAX TEMPS INTO
THE 60S...POSSIBLY 70F ACROSS SOME LOCATIONS. RETURN FLOW BEGINS
TONIGHT ACROSS THE WESTERN FA...WITH MIN TEMPS LIKELY UPPER 30S
EAST TO MID 40S WEST.

SYSTEM BEGINS TO APPROACH THE REGION ON MONDAY. MUCH OF MONDAY
SHOULD BE PARTLY SUNNY WITH TEMPS INTO THE 70S. MODELS SUGGEST
THAT AN 850MB JET AND ASSOCIATED WARM AIR ADVECTION WILL LEAD TO
SCATTERED SHOWERS/THUNDER ACROSS THE NORTHERN FA LATE MONDAY
AFTERNOON INTO MONDAY NIGHT AND TUESDAY MORNING (PROPAGATING
EAST). INSTABILITY IS VERY WEAK.

ON TUESDAY...COLD FRONT WILL BE LOCATED SOMEWHERE ACROSS CENTRAL
DAKOTAS BY 00Z WED. MUCH OF TUESDAY AFTERNOON SHOULD REMAIN DRY AS
LOW-LEVEL MOISTURE IS MARGINAL AND CAPPING HOLDS. STRONG FORCING
FROM APPROACHING MID-LEVEL WAVE WILL BE REQUIRED TO INITIATE
CONVECTION. STRONG DEEP LAYER SHEAR AND SHOWALTER INDEX OF -4C TO
-6C COULD LEAD TO A PERIOD OF POSSIBLE SEVERE STORMS TUESDAY
EVENING INTO THE OVERNIGHT HOURS.

.LONG TERM (WEDNESDAY-SATURDAY)... ODELS CONTINUE TO REMAIN IN
DECENT AGREEMENT WITH THE EXTENDED PERIOD WITH ACTIVE 500MB SW
FLOW TO BRING POPS TO MOST PERIODS IN LATTER HALF OF THE WEEK.
SHORT WAVE MOVING ACROSS THE FA ON WEDNESDAY SHOULD HAVE AMPLE
MOISTURE TO WORK WITH AS DEW POINTS ARE EXPECTED TO LIFT INTO THE
50S AND NEAR 60 AHEAD OF FROPA... INITIATING SHOWERS AND TSTORMS.
SOME UNCERTAINTY ON THURSDAY WITH AREAL COVERAGE OF SHOWER
ACTIVITY AS GFS IS A SLOWER THAN THE ECMWF IN MOVING THE VORT MAX
OVER THE FA WITH LINGERING SHOWERS. A BRIEF BREAK IN THE AREAL
POPS COVERAGE ON FRIDAY BEFORE THE WARM SECTOR SURGES NORTH INTO
THE FA WITH THE INCREASED RIDGING IN THE CENTRAL PLAINS IN
RESPONSE TO THE DEEPENING WEST COAST TROUGH. THIS WAA WARRANTS
SLIGHT CHC POPS ON FRIDAY AND SATURDAY. TEMPS FOR THE PERIOD WILL
BE SEASONAL WITH HIGHS IN THE UPPER 60S AND MID 70S.

&&

.AVIATION...MVFR CIGS REMAIN AT BEMIDJI...AND CLEARING TREND IS
DIFFICULT TO FORECAST. WILL NEED TO MONITOR...THINKING MVFR
THRU 12Z-14Z USING 06Z RUC 925-850MB RELATIVE HUMIDITY. VFR
CONDITIONS THROUGH THE DAY WITH HIGH BASED CU POSSIBLE DURING THE
AFTERNOON HOURS.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$
TG/JK






AREA FORECAST DISCUSSION

NWS WILMINGTON OH

 1026 PM EDT MON MAY 21 2012

.SYNOPSIS...
A WEAK COLD FRONT AND LOW PRESSURE SYSTEM WILL MOVE EAST ACROSS
THE REGION TODAY. THE LOW WILL THEN REMAIN JUST SOUTHWEST OF THE
REGION THROUGH WEDNESDAY. AN UPPER LEVEL RIDGE WILL THEN MOVE INTO
THE AREA FOR THE END OF THE WEEK...BRINGING MUCH WARMER
TEMPERATURES AND DRY CONDITIONS.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
CONVECTION CONTINUES TO SIMMER AND BUILD WWD ACROSS CENTRAL AND SW
PORTIONS OF THE FA. EVEN SEEING SOME LINGERING SHRA IN CNTL OH.
LATEST RAP RUN IS SHOWING THAT THE CONVECTION WILL SLOWLY FADE AS
IT SLIPS SW INTO KY OVER THE NEXT FEW HOURS. UPDATED THE POPS TO
SHOW THIS TREND.

INCREASE THE CLOUD COVER OVERNIGHT...BASED ON SATELLITE LOOP AND
FCST PROGS THAT ARE SHOWING AN INCREASE IN LOW LEVEL MOISTURE.
KEPT FCST LOWS PRETTY MUCH THE SAME...JUST A TWEAK HERE OR THERE.


&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
A CLOSED UPPER LOW IS FORECAST TO DEVELOP IN THE CAROLINAS BY
LATE TUESDAY...WITH WEAK SURFACE LOW PRESSURE EXTENDING NORTH INTO
THE MIDDLE APPALACHIANS (SOMEWHAT A REMNANT OF THE FRONT AND LOW
CROSSING THE AREA TODAY). SHOWERS AND POSSIBLY SOME WEAK
THUNDERSTORMS WILL BE POSSIBLE IN THE REGIONS CLOSEST TO THIS
FEATURE...MAINLY THE SOUTHEAST PART OF THE CWA...ON BOTH TUESDAY
AND WEDNESDAY. THE WEATHER GRIDS ARE SKEWED HEAVILY TOWARD THE
DIURNAL CYCLE...AS THE WEAK FORCING INDICATES THAT THIS WILL
PRIMARILY BE AN INSTABILITY-DRIVEN SITUATION.

AT THE SAME TIME...A NARROW RIDGE OF HIGH PRESSURE WILL BE MOVING
INTO THE GREAT LAKES AND LOWER OHIO VALLEY REGIONS. THE PRESSURE
PATTERN WILL BECOME RATHER DIFFUSE BY WEDNESDAY...WITH MEAN
SOUTHERLY FLOW BEGINNING TO SET UP AS THE PRESSURE GRADIENT TO THE
WEST BEGINS TO TIGHTEN ON WEDNESDAY NIGHT AND INTO THURSDAY.

THE ECMWF IS A LITTLE BIT SLOWER IN MOVING THE UPPER LOW OUT OF
THE SOUTH...BUT THE OVERALL PATTERN IS IN AGREEMENT BETWEEN
MODELS...WITH A WARMING AND DRYING TREND DURING THE TUESDAY
THROUGH THURSDAY PERIOD.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
PESKY UPR LVL CLOSED LOW TO THE SOUTHEAST OF THE REGION IS EXPECTED
TO OPEN UP AND EJECT TO THE NE AS AN UPR LVL HIGH BEGINS TO
BUILD ACRS THE WRN FORECAST AREA ON THURSDAY. THERE COULD STILL BE A
VERY SMALL CHANCE FOR A POP UP SHOWER OR STORM THURSDAY IN THE FAR
SE...BUT HAVE DECIDED TO STILL KEEP THE FORECAST DRY. TEMPERATURES
WILL CONTINUE TO WARM TO ABOVE NORMAL READINGS.

FOR THURSDAY NIGHT INTO SUNDAY...UPR LVL RIDGE WILL CONTINUE TO
BUILD INTO THE OHIO VALLEY. A COLD FRONT WILL TRY TO NUDGE SOUTHWARD
CLOSE TO THE FAR NRN ZONES FRIDAY AFTERNOON AND EVENING. HAVE KEPT
IT DRY BUT IF THE FRONT GETS TOO CLOSE...A SLIGHT CHANCE OF A SHOWER
OR STORM MAY HAVE TO BE ADDED. FOR SATURDAY INTO SATURDAY
NIGHT...HAVE TAKEN A BLEND OF THE 00Z ECMWF AND NCEP/HPC WHICH KEEPS
THE FRONT JUST NEAR OUR FAR NRN/NERN BORDER. HAVE KEPT A SLIGHT
CHANCE OF PCPN FOR THESE LOCATIONS DURING THE AFTN AND EVENING.
ON SUNDAY...RIDGE IS EXPECTED TO HAVE ITS BEST INFLUENCE ON THE
REGION...SO SKIES SHOULD BE MOSTLY SUNNY WITH WEAK FRONTAL BOUNDARY
EITHER DISSIPATING OR PUSHING NE OF THE REGION. DRY WX IS EXPECTED.
AS FOR TEMPERATURES...THEY WILL WARM SLIGHTLY EACH DAY WITH HOT
WEATHER EXPECTED THIS WEEKEND WITH HIGHS LOWER 90S.

ON MONDAY...MEMORIAL DAY...UPR LVL RIDGE WILL BEGIN TO WEAKEN AND
MOVE OFF TO THE EAST. TEMPERATURES WILL STILL BE HOT...AROUND 90.  A
POP UP SHOWER OR THUNDERSTORM IS POSSIBLE DURING THE HEAT OF THE DAY
AS CAP ALOFT WEAKENS.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
CONVECTION CONTINUES ALONG A BOUNDARY RUNNING FROM NR CMH-LCK-ILN
INTO NE KY. ALTHOUGH SOME OF THESE CELLS HAVE SHOWN A WWD
BUILDING CHARACTERISTIC THIS EVENING...EXPECT IT TO STAY TO THE E
OF THE ERN TAFS. WITH LOSS OF DAYTIME HEATING THE CONVECTION
SHOULD DISSIPATE.

MODELS ARE INCREASING H9 MOISTURE BETWEEN 06-12Z. THIS
CORRESPONDS WITH THE SOME LOW CLOUDS IN LOWER MI. BROUGHT MVFR
CIGS INTO THE TAFS WITH THIS HIGHER RH.

DIGGING H5 TROF TRIES TO FORM A CUTOFF LOW IN THE APPALACHIANS ON
TUESDAY. LIFT FROM THIS SYSTEM CREATES SOME SHRA IN SE OH...WHICH
MIGHT BUILDS BACK TO NR ILN-CMH-LCK. WENT VCSH AT THIS TIME IN THE
TAFS. THE IFR CLOUDS WILL GRADUALLY LIFT DURING THE DAY TOMORROW.


OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

&&

$$
SYNOPSIS...HATZOS
NEAR TERM...SITES
SHORT TERM...HATZOS
LONG TERM...HICKMAN
AVIATION...SITES








AREA FORECAST DISCUSSION

NWS CLEVELAND OH

 937 PM EDT MON MAY 21 2012

.SYNOPSIS...
A COLD FRONT WILL MOVE OUT OF THE AREA THIS EVENING. HIGH
PRESSURE WILL GRADUALLY BUILD EAST OVER THE REGION BY WEDNESDAY
MORNING. THE HIGH PRESSURE CENTER WILL MOVE TO THE EAST COAST BY
WEDNESDAY NIGHT ALLOWING A WARM FRONT TO LIFT NORTH ACROSS THE
AREA THURSDAY. A WEAK COLD FRONT WILL APPROACH THE AREA LATE FRIDAY.

&&

.NEAR TERM /THROUGH 6 AM TUESDAY/...
EXCEPT FOR A CLUSTER OF CONVECTION CENTERED IN WAYNE CO...MUCH OF
THE DAYTIME CONVECTION HAD DISSIPATED. A BAND OF SHRA IN THE COOLER
AIR OVER THE WESTERN PART OF THE AREA ASSOCIATED WITH THE UPPER
TROUGH IS TRYING TO GET GOING BUT WILL HAVE A HARD TIME DUE TO A
MORE STABLE AIRMASS IN THAT AREA. WILL KEEP SMALL CHANCE GOING FOR
MOST AREAS THROUGH MIDNIGHT THEN BEGIN TO SHIFT CHANCE INTO THE
SOUTHEAST HALF OF THE AREA OVER THE COURSE OF THE REST OF THE NIGHT.
RUC AND HRRR DISAGREE SO OVERALL CONFIDENCE LOW FOR THE REST OF THE
NIGHT BUT DO FEEL ANY NEW ACTIVITY WILL BE LIGHT.

REST OF FORECAST SEEMS TO BE ON TRACK SO LITTLE WILL BE CHANGED.

&&

.SHORT TERM /6 AM TUESDAY THROUGH THURSDAY NIGHT/...THE FRONT WILL
BE JUST TO THE EAST OF THE FORECAST AREA. WITH A FAIR AMOUNT OF
MOISTURE...WILL CONTINUE WITH CHANCE POPS INTO THE
AFTERNOON...MAINLY IN THE EAST...WITH DECREASING CLOUDS ELSEWHERE.
OTHERWISE HIGH PRESSURE BUILDING IN TUESDAY NIGHT AND THE HIGH WILL
WEAKEN WEDNESDAY NIGHT. A WARM FRONT WILL MOVE ACROSS THE AREA
THURSDAY. ON THE EDGE ABOUT THE THREAT OF PRECIPITATION...ANY QPF
WOULD BE VERY LIGHT. JUST WENT WITH 20 POPS AT THE MOMENT AND WILL
MONITOR IT CLOSELY.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
BEGINNING FRIDAY IN THE LONG TERM GFS AND ECMWF SHOWING COLD FRONT
APPROACHING THE AREA BUT LOOKS LIKE TEMPS WILL BE QUITE ABOVE NORMAL
WITH SHOWERS AND THUNDERSTORMS HOLDING OFF MOVING INTO WESTERN AREAS
UNTIL LATE DAY/EVENING...WITH BETTER CHANCES ACROSS THE NORTHERN
HALF OF THE AREA FRIDAY NIGHT. THE PATTERN LOOKS TO BE TRICKY GOING
INTO THE WEEKEND HOWEVER WITH BOTH MODELS SHOWING THE FRONTAL
BOUNDARY ORIENTING ITSELF MORE WEST TO EAST ACROSS THE AREA ON
SATURDAY. WITH THE BOUNDARY ACROSS THE AREA THE CHANCES FOR SHOWERS
AND THUNDERSTORMS WILL CONTINUE. HOWEVER...GIVEN THIS FAR OUT IN THE
EXTENDED MAINLY WENT WITH LOW CHC TO SLGT CHC POPS ON SATURDAY.
THERE IS SOME DISCREPANCY WITH HOW STRONG HIGH PRESSURE TO THE NORTH
MAY RIDGE INTO THE AREA ON SUNDAY PUSHING THE FRONT FURTHER SOUTH
AWAY FROM THE AREA...BUT FOR NOW LEANED TOWARD DRIER CONDITIONS
GIVEN LOW CONFIDENCE ON TIMING OF ANY PRECIP. GIVEN MODEL
DIFFERENCES IN THE LONG TERM LEANED MORE TOWARD PREVIOUS FORECAST
TEMPS OVER SAT AND SUN GIVEN MODEL DIFFERENCES.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
A COLD FRONT CONTINUES TO MAKE SLOW PROGRESS ACROSS THE AREA. THE
FRONT APPEARS TO BE JUST EAST OF I-71 AND SHOULD BE EAST OF THE
AREA BY O6Z. SOME SCATTERED CONVECTION CONTINUES ALONG THE FRONT.
THERE HAS BEEN A GRADUAL WEAKENING TREND BUT SOME THUNDER COULD
OCCUR THE NEXT COUPLE OF HOURS. BEST CHANCES FOR THIS WILL BE NEAR
KYNG AND KMFD. WILL GIVE THOSE TWO SITES A BRIEF MENTION OF PRECIP
AND KCAK TOO. OTHERWISE WILL TRY FOR A DRY FORECAST AS COVERAGE
REMAINS SMALL. SOME MVFR CIGS HAVE MOVED INTO NW OH AND WILL ALSO
GIVE ALL OF THE TAF SITES A FEW HOURS OF MVFR CIGS SIMILAR TO
PREVIOUS PACKAGE. WINDS BEHIND THE FRONT WILL BECOME NW WITH NW TO
N FLOW THEN EXPECTED THROUGH THE END OF THE TAF PERIOD. DRIER AIR
ARRIVES TOMORROW AND WILL SCT THINGS OUT.

.OUTLOOK...NON-VFR POSSIBLE IN EARLY MORNING FOG/HAZE WEDNESDAY.

&&

.MARINE...
WEAK COLD FRONT HAS PUSHED ACROSS THE WESTERN BASIN OF LAKE ERIE AND
WILL CLEAR THE EASTERN PORTION OF THE LAKE OVERNIGHT...WITH WINDS
SHIFTING TO NORTHWEST NEAR 10 KNOTS BEHIND THE FRONT. SCATTERED
SHOWERS OR AN ISOLATED THUNDERSTORM WILL BE POSSIBLE INTO THIS
EVENING AS MOISTURE INCREASES ALONG AND BEHIND THE FRONT. A MARGINAL
INCREASE IN WAVES TO 2 TO 3 FEET CAN BE EXPECTED WITH THE ONSHORE
FLOW TOWARDS TUESDAY MORNING.

HIGH PRESSURE WILL BUILD EAST ACROSS THE REGION ON WEDNESDAY WITH
WINDS SLOWLY VEERING TO SOUTHEAST LY ON THURSDAY. A WARM FRONT WILL
LIFT BACK NORTH ACROSS THE LAKE TOWARDS THE END OF THE WEEK WITH
GENERALLY LIGHT SOUTHERLY WINDS AND STABLE CONDITIONS.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...KIELTYKA
NEAR TERM...KIELTYKA/ADAMS
SHORT TERM...KIELTYKA
LONG TERM...ABE
AVIATION...KUBINA
MARINE...KEC










AREA FORECAST DISCUSSION

NWS CLEVELAND OH

 616 PM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER PENNSYLVANIA AND NEW YORK WILL WEAKEN
OVER THE AREA THROUGH TONIGHT. A COLD FRONT WILL MOVE THROUGH THE
AREA TOMORROW...BUT THEN BECOME STATIONARY ALONG THE APPALACHIANS
EARLY NEXT WEEK. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE
WEST THROUGH TUESDAY NIGHT.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
FOR 630 PM UPDATE...ONLY CHANGE WAS TO RAISE LOWS A DEG OR TWO WEST
TWO-THIRDS DUE TO EXPECTED INCREASED CLOUDS AND SOUTH WINDS AHEAD OF
COLD FRONT THAT ARRIVES ON MON. DRY LOW LEVELS SHOULD KEEP RAIN WEST
OF AREA THROUGH DAYBREAK ALTHOUGH FIRST BAND OF WEAKENING SHRA/TSRA
COULD MAKE A RUN TOWARD THE WESTERN OH BORDER BY MIDNIGHT BEFORE
DISSIPATING.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
MODELS STARTING OFF MONDAY MAINLY DRY ACROSS THE FORECAST AREA.
BRING IN LOW POPS ACROSS THE FAR WEST WITH COLD FRONT EXPECTED TO
BE MOVING INTO NW OH AROUND 12Z. FROM THERE INCREASE POPS QUICKLY
IN THE MORNING AS QUICK HEATING WILL PROVIDE GOOD SFC INSTABILITY
WITH CAPE INCREASING TOWARD 1500 J/KG AND LI/S DROPPING DOWN
AROUND -5. EXPAND CHC/S OF SHOWERS AND THUNDERSTORMS EAST ACROSS
THE AREA THROUGH THE AFTERNOON. FOR NOW WENT WITH CHC POPS GIVEN
SCATTERED COVERAGE OF ACTIVITY...BUT IF A MORE DEFINED LINE OF
CONVECTION DOES DEVELOP OR ANTICIPATED BASED ON GUIDANCE TONIGHT
THEN PERHAPS POPS COULD BE RAISED TO LIKELY WITH SOME REFINED
TIMING.

THINKING THAT SHRA/TS WILL GET INTO CENTRAL AREAS FROM CLE-MFD
EARLY TO MID AFTERNOON...THEN BY AROUND 20Z-22Z ACROSS THE EAST.
NOT VERY CONFIDENT ON PRECIP SPREADING WESTWARD FROM THE EAST
COAST...BUT IT MAY PROVIDE SOME ADDITIONAL MOISTURE FOR THE FRONT
TO WORK WITH LATER TOMORROW/EARLY TOMORROW NIGHT. WITH MORE CU
AROUND TOMORROW AND PRECIP CHANCES DID GO A BIT COOLER TODAY...BUT
WILL HAVE TO WATCH EASTERN AREAS AS DEPENDING ON TIMING THEY MAY
HAVE ANOTHER MID 80S DAY.

MODELS DIFFER A BIT MONDAY NIGHT AND TUESDAY WITH THE SPEED ON
DRYING OUT THE AREA. THE FRONT LOOKS TO BE STALLING EAST OF THE
AREA...PLUS AN UPPER LOW/TROUGH SOUTH OF THE AREA MAY KEEP THE
POSSIBILITY OF SHOWERS ACROSS EASTERN AREAS THROUGH TUESDAY. HIGH
PRESSURE LOOKS LIKE IT WILL BE STRONG ENOUGH TO RIDGE INTO WESTERN
AREAS ALLOWING FOR DRY CONDITIONS ACROSS PERHAPS THE WESTERN HALF
OF THE FORECAST AREA. GIVEN MODEL DIFFERENCES CONFIDENCE A BIT
LOWER AT THIS TIME BUT FOR NOW LEANED TOWARD DRY CONDITIONS
EVERYWHERE WITH HIGH PRESSURE BY WEDNESDAY AND WEDNESDAY NIGHT.
WITH THE FRONT SOUTH AND EAST OF THE AREA TUESDAY MODEL TEMPS
SHOWING COOLER CONDITIONS WITH HIGH MAINLY AROUND 70...WITH
MODERATING TEMPS TO THE MID 70S WEDNESDAY.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AN UPPER RIDGE WILL BE BUILDING INTO THE AREA STARTING THURSDAY AS
THE UPPER LOW WILL BE MOVING EAST FROM THE MIDDLE ATLANTIC STATES.
SOME QUESTION HOW QUICKLY THE LOW WILL MOVE EAST AND WHETHER SOME
SHOWERS COULD BE LINGERING OVER NORTHWEST PA THURSDAY. BASED ON THE
LOCATION OF THE UPPER LOW...WILL KEEP IT DRY.

FOR FRIDAY AND THE WEEKEND A WEAK COLD FRONT IS EXPECTED TO MOVE
ACROSS THE REGION FRIDAY...THE GFS AND 12Z ECMWF AGREE. THE
DISAGREEMENT IS WHAT WILL HAPPEN SATURDAY AND SUNDAY. THE GFS HAS
HIGH PRESSURE BUILDING IN STRONGLY FROM THE NORTH...WHILE THE ECMWF
KEEPS A FRONTAL BOUNDARY WEST TO EAST ACROSS OHIO. AT THIS TIME
LEANED TOWARD KEEPING IT DRY AND WENT CLOSE TO HPC GUIDANCE FOR THE
TEMPERATURES.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS CONTINUING THROUGH MONDAY MORNING. A LAKE BREEZE
DEVELOPED VERY QUICKLY TODAY AND CONTINUES TO MOVE SLOWLY SOUTH.
THE LAKE BREEZE WILL DISSIPATE AROUND DAYBREAK. THE LAKE BREEZE
WAS ENOUGH CONVERGENCE TO GENERATE A FEW CUMULUS CLOUDS OVER
NORTHEAST OHIO. OTHERWISE JUST SOME CIRRUS THIS AFTERNOON...INTO
TONIGHT. THE HRRR MODELS HAS SHOWERS ON THE IN AND OH BORDER BY
05Z...IT LOOKS LIKE THEY SHOULD DISSIPATE. THIS WILL HAVE TO BE
WATCHED.

TWO WEATHER SYSTEMS WILL BE AFFECTING THE REGION MONDAY. A COLD
FRONT WILL BE MOVING IN FROM THE WEST WITH INCREASING CLOUDS. AN
UPPER LOW WILL BE MOVING SOUTH TO NORTH OVER PENNSYLVANIA AND THIS
MAY BRING SOME CLOUDS AND POSSIBLY SHOWERS INTO NORTHWEST
PA MONDAY AFTERNOON. THE TIMING OF THE SHOWERS AND THUNDERSTORMS
OVER NORTHWEST OH IS A LITTLE TRICKY...GOING WITH MID TO LATE
AFTERNOON MONDAY.

.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
SHOWERS/THUNDERSTORMS MONDAY AFTERNOON AND TUESDAY. EARLY
MORNING FOG/HAZE MAY ALSO OCCUR TUESDAY AND WEDNESDAY.

&&

.MARINE...
RIDGE ACROSS THE LAKE WILL WEAKEN AND MOVE EAST TONIGHT AS A WEAK
COLD FRONT MOVES TOWARD THE AREA. THE COLD FRONT WILL MOVE ACROSS
THE LAKE MONDAY THROUGH MONDAY EVENING...THEN HIGH PRESSURE WILL
BUILD BACK IN. ANOTHER WEAK COLD FRONT WILL MOVE ACROSS THE LAKE
FRIDAY. HIGH PRESSURE WILL THEN BEGIN TO BUILD IN FROM THE NORTH FOR
THE WEEKEND.

THE CONCERNS ON THE LAKE ARE SOME THUNDERSTORMS COULD DEVELOP MONDAY
AFTERNOON NEEDING A SPECIAL MARINE WARNING. BEHIND THE COLD FRONT
MONDAY NIGHT THE WINDS PICK UP AND THE WAVES COULD BE CLOSE TO SMALL
CRAFT ADVISORY CRITERIA...THIS WILL HAVE TO BE MONITORED. THE NEXT
THREAT FOR A SMALL CRAFT ADVISORY COULD BE OVER THE WEEKEND...WITH A
NORTHEAST FLOW AND HIGH PRESSURE TO THE NORTH. SOME MODEL
DIFFERENCES ON THIS FEATURE.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...ABE
NEAR TERM...ABE/ADAMS
SHORT TERM...ABE
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA










AREA FORECAST DISCUSSION

NWS CLEVELAND OH

 340 PM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER PENNSYLVANIA AND NEW YORK WILL WEAKEN
OVER THE AREA THROUGH TONIGHT. A COLD FRONT WILL MOVE THROUGH THE
AREA TOMORROW...BUT THEN BECOME STATIONARY ALONG THE APPALACHIANS
EARLY NEXT WEEK. HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE
WEST THROUGH TUESDAY NIGHT.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
HIGH PRESSURE CENTERED OVER NY AND PA WILL CONTINUE TO KEEP
CONDITIONS DRY ACROSS THE FORECAST AREA TONIGHT. EXPECTING SOME
CIRRUS CLOUDS TO CONTINUE ACROSS THE AREA WITH LITTLE IMPACT.
TEMPS WILL BE TRICKY WITH RADIATING CONDITIONS LIKELY ACROSS THE
COOLER SPOTS INCLUDING INTERIOR NW PA...BUT WESTERN AREAS MAY SEE
MILDER LOWS GIVEN INCREASING MOISTURE AND SOUTHERLY FLOW
DEVELOPING/OR INCREASING DURING THE OVERNIGHT. USED MAINLY MAV
TEMPS WITH SOME LOCAL ADJUSTMENTS. OVERALL WENT WITH MID TO UPPER
50S ACROSS THE EASTERN 2/3 OF THE AREA AND LOWS AROUND 60 ACROSS
THE FAR WEST.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
MODELS STARTING OFF MONDAY MAINLY DRY ACROSS THE FORECAST AREA.
BRING IN LOW POPS ACROSS THE FAR WEST WITH COLD FRONT EXPECTED TO
BE MOVING INTO NW OH AROUND 12Z. FROM THERE INCREASE POPS QUICKLY
IN THE MORNING AS QUICK HEATING WILL PROVIDE GOOD SFC INSTABILITY
WITH CAPE INCREASING TOWARD 1500 J/KG AND LI/S DROPPING DOWN
AROUND -5. EXPAND CHC/S OF SHOWERS AND THUNDERSTORMS EAST ACROSS
THE AREA THROUGH THE AFTERNOON. FOR NOW WENT WITH CHC POPS GIVEN
SCATTERED COVERAGE OF ACTIVITY...BUT IF A MORE DEFINED LINE OF
CONVECTION DOES DEVELOP OR ANTICIPATED BASED ON GUIDANCE TONIGHT
THEN PERHAPS POPS COULD BE RAISED TO LIKELY WITH SOME REFINED
TIMING.

THINKING THAT SHRA/TS WILL GET INTO CENTRAL AREAS FROM CLE-MFD
EARLY TO MID AFTERNOON...THEN BY AROUND 20Z-22Z ACROSS THE EAST.
NOT VERY CONFIDENT ON PRECIP SPREADING WESTWARD FROM THE EAST
COAST...BUT IT MAY PROVIDE SOME ADDITIONAL MOISTURE FOR THE FRONT
TO WORK WITH LATER TOMORROW/EARLY TOMORROW NIGHT. WITH MORE CU
AROUND TOMORROW AND PRECIP CHANCES DID GO A BIT COOLER TODAY...BUT
WILL HAVE TO WATCH EASTERN AREAS AS DEPENDING ON TIMING THEY MAY
HAVE ANOTHER MID 80S DAY.

MODELS DIFFER A BIT MONDAY NIGHT AND TUESDAY WITH THE SPEED ON
DRYING OUT THE AREA. THE FRONT LOOKS TO BE STALLING EAST OF THE
AREA...PLUS AN UPPER LOW/TROUGH SOUTH OF THE AREA MAY KEEP THE
POSSIBILITY OF SHOWERS ACROSS EASTERN AREAS THROUGH TUESDAY. HIGH
PRESSURE LOOKS LIKE IT WILL BE STRONG ENOUGH TO RIDGE INTO WESTERN
AREAS ALLOWING FOR DRY CONDITIONS ACROSS PERHAPS THE WESTERN HALF
OF THE FORECAST AREA. GIVEN MODEL DIFFERENCES CONFIDENCE A BIT
LOWER AT THIS TIME BUT FOR NOW LEANED TOWARD DRY CONDITIONS
EVERYWHERE WITH HIGH PRESSURE BY WEDNESDAY AND WEDNESDAY NIGHT.
WITH THE FRONT SOUTH AND EAST OF THE AREA TUESDAY MODEL TEMPS
SHOWING COOLER CONDITIONS WITH HIGH MAINLY AROUND 70...WITH
MODERATING TEMPS TO THE MID 70S WEDNESDAY.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AN UPPER RIDGE WILL BE BUILDING INTO THE AREA STARTING THURSDAY AS
THE UPPER LOW WILL BE MOVING EAST FROM THE MIDDLE ATLANTIC STATES.
SOME QUESTION HOW QUICKLY THE LOW WILL MOVE EAST AND WHETHER SOME
SHOWERS COULD BE LINGERING OVER NORTHWEST PA THURSDAY. BASED ON THE
LOCATION OF THE UPPER LOW...WILL KEEP IT DRY.

FOR FRIDAY AND THE WEEKEND A WEAK COLD FRONT IS EXPECTED TO MOVE
ACROSS THE REGION FRIDAY...THE GFS AND 12Z ECMWF AGREE. THE
DISAGREEMENT IS WHAT WILL HAPPEN SATURDAY AND SUNDAY. THE GFS HAS
HIGH PRESSURE BUILDING IN STRONGLY FROM THE NORTH...WHILE THE ECMWF
KEEPS A FRONTAL BOUNDARY WEST TO EAST ACROSS OHIO. AT THIS TIME
LEANED TOWARD KEEPING IT DRY AND WENT CLOSE TO HPC GUIDANCE FOR THE
TEMPERATURES.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS CONTINUING THROUGH MONDAY MORNING. A LAKE BREEZE
DEVELOPED VERY QUICKLY TODAY AND CONTINUES TO MOVE SLOWLY SOUTH.
THE LAKE BREEZE WILL DISSIPATE AROUND DAYBREAK. THE LAKE BREEZE
WAS ENOUGH CONVERGENCE TO GENERATE A FEW CUMULUS CLOUDS OVER
NORTHEAST OHIO. OTHERWISE JUST SOME CIRRUS THIS AFTERNOON...INTO
TONIGHT. THE HRRR MODELS HAS SHOWERS ON THE IN AND OH BORDER BY
05Z...IT LOOKS LIKE THEY SHOULD DISSIPATE. THIS WILL HAVE TO BE WATCHED.

TWO WEATHER SYSTEMS WILL BE AFFECTING THE REGION MONDAY. A COLD
FRONT WILL BE MOVING IN FROM THE WEST WITH INCREASING CLOUDS. AN
UPPER LOW WILL BE MOVING SOUTH TO NORTH OVER PENNSYLVANIA AND THIS
MAY BRING SOME CLOUDS AND POSSIBLY SHOWERS INTO NORTHWEST
PA MONDAY AFTERNOON. THE TIMING OF THE SHOWERS AND THUNDERSTORMS
OVER NORTHWEST OH IS A LITTLE TRICKY...GOING WITH MID TO LATE
AFTERNOON MONDAY.

.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
SHOWERS/THUNDERSTORMS MONDAY AFTERNOON AND TUESDAY. EARLY
MORNING FOG/HAZE MAY ALSO OCCUR TUESDAY AND WEDNESDAY.

&&

.MARINE...
RIDGE ACROSS THE LAKE WILL WEAKEN AND MOVE EAST TONIGHT AS A WEAK
COLD FRONT MOVES TOWARD THE AREA. THE COLD FRONT WILL MOVE ACROSS
THE LAKE MONDAY THROUGH MONDAY EVENING...THEN HIGH PRESSURE WILL
BUILD BACK IN. ANOTHER WEAK COLD FRONT WILL MOVE ACROSS THE LAKE
FRIDAY. HIGH PRESSURE WILL THEN BEGIN TO BUILD IN FROM THE NORTH FOR
THE WEEKEND.

THE CONCERNS ON THE LAKE ARE SOME THUNDERSTORMS COULD DEVELOP MONDAY
AFTERNOON NEEDING A SPECIAL MARINE WARNING. BEHIND THE COLD FRONT
MONDAY NIGHT THE WINDS PICK UP AND THE WAVES COULD BE CLOSE TO SMALL
CRAFT ADVISORY CRITERIA...THIS WILL HAVE TO BE MONITORED. THE NEXT
THREAT FOR A SMALL CRAFT ADVISORY COULD BE OVER THE WEEKEND...WITH A
NORTHEAST FLOW AND HIGH PRESSURE TO THE NORTH. SOME MODEL
DIFFERENCES ON THIS FEATURE.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...ABE
NEAR TERM...ABE
SHORT TERM...ABE
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA







AREA FORECAST DISCUSSION

NWS CLEVELAND OH

 146 PM EDT SUN MAY 20 2012

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER PENNSYLVANIA AND NEW YORK WILL MOVE
GRADUALLY EAST TO THE EAST COAST BY THIS EVENING. LOW PRESSURE WILL
MOVE EAST TO THE LOWER GREAT LAKES WITH A TRAILING COLD FRONT ON
MONDAY. A WEAK WAVE OF LOW PRESSURE WILL MOVE NORTH ALONG THE
APPALACHIAN MOUNTAINS TO CENTRAL NEW YORK BY TUESDAY AFTERNOON. A
RIDGE OF HIGH PRESSURE WILL BUILD SOUTH ACROSS THE AREA ON
WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MOSTLY SUNNY SKIES ACROSS MUCH OF THE AREA THIS AFTERNOON. SOME
THIN CIRRUS ACROSS THE WEST CONTINUES TO MOVE NORTHWARD. ADJUSTED
TEMPS ESPECIALLY WITH LAKE BREEZE KICKING IN WITH TEMPS MAXED OUT
AT ERI AND ALONG THE REMAINING LAKESHORE LOCATIONS. RADAR SHOWS
ONLY FAINT LAKE BREEZE RETURN NEAR CLE AS OF 16Z.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
COLD FRONT AND ASSOCIATED LOW PRESSURE ARRIVE ON MONDAY AND BRING
WITH IT DEEPER MOISTURE AND A CHANCE FOR SHOWERS AND THUNDERSTORMS.
DUE TO THE WARM AIR ADVECTION EXPECTED...SOME INSTABILITY WILL
DEVELOP ACROSS THE AREA TO PRODUCE THUNDERSTORMS. I STILL THINK THE
CENTRAL PORTIONS OF THE FORECAST AREA COULD ESCAPE THE SHOWERS UNTIL
LATER IN THE EVENING AS MODELS ARE CONSISTENT IN HOLDING MOISTURE
BACK IN THE CENTRAL AND EASTERN PORTIONS UNTIL EVENING. BUT...WILL
STICK WITH EARLIER FORECAST AND KEEP THE SLIGHT CHANCE GOING IN THE
FORECAST FOR NOW.

MOISTURE ASSOCIATED WITH THE TROPICAL SYSTEM OFF THE CAROLINA COAST
WILL STREAM NORTH JUST WEST OF THE APPALACHIAN MOUNTAINS BY MONDAY
EVENING. THE MOISTURE SOURCE TO THE WEST AND THE TROPICAL MOISTURE
WILL MERGE OVER THE FORECAST AREA MONDAY NIGHT AND KEEP THE THREAT
FOR SHOWERS AND THUNDERSTORMS GOING.

THE COLD FRONT AND MERGED LOW PRESSURE SYSTEMS TAKE THERE GOOD OLD
TIME GETTING OUT OF THE AREA AND WILL LEAVE A LINGERING THREAT FOR
SHOWERS AND THUNDERSTORMS INTO TUESDAY...TUESDAY NIGHT AND EXITING
FINALLY ON WEDNESDAY. HIGH PRESSURE BUILDS SOUTH ACROSS THE AREA
ENDING THE THREAT FOR PRECIPITATION BY WEDNESDAY NIGHT.

DUE TO THE WEAK COLD AIR ADVECTION EXPECTED ALONG WITH THE CLOUD
COVER AND THREAT FOR SHOWERS...WILL SLIDE TEMPERATURES DOWN A COUPLE
DEGREES FROM MONDAY NIGHT THROUGH WEDNESDAY NIGHT.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
THE GFS CONTINUES TO BRING A WEAKENING COLD FRONT OR TROUGH ACROSS
THE AREA ON FRIDAY. THERE IS SOME UNCERTAINTY WITH THE FRONT... AND
THE CONSENSUS IS TO GO WITH A LESS AGGRESSIVE FRONTAL MOVEMENT...
WITH THE FRONT STAYING JUST NORTH OF THE AREA LATE IN THE WEEK. THIS
WOULD KEEP THE AREA WITHIN THE BUILDING RIDGE AND THE SOUTHWEST
FLOW. TEMPERATURES WOULD WARM WELL ABOVE NORMAL WITH HIGHS WELL INTO
THE 80S TO AROUND 90 BY THE WEEKEND.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS CONTINUING THROUGH MONDAY MORNING. A LAKE BREEZE
DEVELOPED VERY QUICKLY TODAY AND CONTINUES TO MOVE SLOWLY SOUTH.
THE LAKE BREEZE WILL DISSIPATE AROUND DAYBREAK. THE LAKE BREEZE
WAS ENOUGH CONVERGENCE TO GENERATE A FEW CUMULUS CLOUDS OVER
NORTHEAST OHIO. OTHERWISE JUST SOME CIRRUS THIS AFTERNOON...INTO
TONIGHT. THE HRRR MODELS HAS SHOWERS ON THE IN AND OH BORDER BY
05Z...IT LOOKS LIKE THEY SHOULD DISSIPATE. THIS WILL HAVE TO BE WATCHED.

TWO WEATHER SYSTEMS WILL BE AFFECTING THE REGION MONDAY. A COLD
FRONT WILL BE MOVING IN FROM THE WEST WITH INCREASING CLOUDS. AN
UPPER LOW WILL BE MOVING SOUTH TO NORTH OVER PENNSYLVANIA AND THIS
MAY BRING SOME CLOUDS AND POSSIBLY SHOWERS INTO NORTHWEST
PA MONDAY AFTERNOON. THE TIMING OF THE SHOWERS AND THUNDERSTORMS
OVER NORTHWEST OH IS A LITTLE TRICKY...GOING WITH MID TO LATE
AFTERNOON MONDAY.

.OUTLOOK...NON-VFR CONDITIONS WILL OCCUR WITH SCATTERED
SHOWERS/THUNDERSTORMS MONDAY AFTERNOON AND TUESDAY. EARLY
MORNING FOG/HAZE MAY ALSO OCCUR TUESDAY AND WEDNESDAY.

&&

.MARINE...
QUIET AGAIN TODAY ON LAKE ERIE WITH HIGH PRESSURE CENTERED OVER
EASTERN LAKE ERIE. WINDS WILL ESSENTIALLY BE LIGHT AND VARIABLE WITH
ONSHORE WINDS DOMINATING BY AFTERNOON.

AS THE HIGH MOVES OFF TO THE EAST THE WIND WILL COME AROUND FROM THE
SOUTH TONIGHT AND CONTINUE FROM THE SOUTH AHEAD OF A COLD FRONT ON
MONDAY. STILL SOME QUESTION AS TO THE TIMING OF THE FRONT. WINDS
COULD BECOME ONSHORE MONDAY AFTERNOON OR VARIABLE AS THE PRESSURE
GRADIENT BECOME LIGHT AND SURFACE PRESSURES FALL.

A NORTH FLOW WILL DEVELOP AFTER THE FRONT MONDAY NIGHT INTO
TUESDAY...THEN THE FLOW WILL VEER MORE FROM THE NORTHEAST AS THE
SURFACE HIGH BUILDS IN DURING THE MIDWEEK. THE GRADIENT APPEARS
LIGHT ENOUGH THAT WIND SPEEDS AND WAVES SHOULD STAY BELOW SMALL
CRAFT ADVISORY CRITERIA.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...LOMBARDY
NEAR TERM...ABE
SHORT TERM...LOMBARDY
LONG TERM...KOSARIK
AVIATION...KIELTYKA
MARINE...KOSARIK








AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

 215 AM EDT SUN MAY 20 2012

.SYNOPSIS...
THE STRONG 500 HPA RIDGE AND WEAK SURFACE RIDGE SHOULD PROVIDE FOR
ANOTHER FINE DAY SUNDAY. A NORTHERN STREAM WAVE APPROACHING COULD
PULL THE FIRST NAMED STORM OF THE YEAR...ALBERTO...UP THE COAST
MONDAY-TUESDAY WHICH COULD BRING A CHANCE OF RAIN TO EASTERN PA
MONDAY EVENING AND TUESDAY. A WEAK TROUGH WILL DOMINATE THROUGH
LATE WEDNESDAY...THEN A 500 HPA RIDGE SHOULD BUILD OVER THE
EASTERN UNITED STATES. BY THE END OF THE WEEK A 5880M RIDGE WITH
+1 TO +2 STANDARD DEVIATIONS HEIGHTS WILL BE OVER THE OHIO
VALLEY. IT SHOULD RAPIDLY WARM UP HERE THURSDAY INTO SATURDAY.
SHOULD BE WELL ABOVE NORMAL HERE TEMPERATURE WISE THUR-SUNDAY.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
HIGH PRESSURE OVER THE REGION WILL PROVIDE ANOTHER MCLEAR NIGHT
ACROSS CENTRAL PA WITH LIGHT WINDS. ORIGINALLY COOL/DRY AIR MASS
HAS MODIFIED CONSIDERABLY OVER THE LAST COUPLE DAYS. 06Z
TEMPS/DWPTS SEVERAL DEG ABV THOSE OF 24HRS AGO...SUGGESTING LOWS
THIS AM RANGING FROM THE U40S N MTNS...TO THE M50S ACROSS THE
LOWER SUSQ VALLEY.

CAN/T RULE OUT A BIT OF FOG ARND DAWN OVR THE SUSQ VALLEY...WHERE
NAM AND HRRR SFC RH RISES TO NR 100PCT BY 09Z. HOWEVER...HAVE
REMOVED MENTION IN FCST...GIVEN UNCERTAINTY AND ISOLATED NATURE IF
IT DOES FORM.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM MONDAY/...
FAIR WX CONTINUES SUNDAY AS A RIDGE OVER THE ATLANTIC EXTENDS INTO
OUR REGION. WE SHOULD HAVE WEAK EASTERLY FLOW SLIGHT RISE IN
RELATIVE HUMIDITY.

SHOULD BE A GOOD DAY AND NEW GUIDANCE STILL SEEMS TO KEEP HINTS OF
RAIN OFF UNTIL MONDAY. STILL NOT AN ENSEMBLE MEMBER HAS ANY RAIN
OVER OUR AREA UNTIL AFTER ABOUT ABOUT 1200 UTC ON MONDAY.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
UPDATED GRIDS/FORECAST TO SHOW THE LATEST GEFS/SREF WITH BEST
CHANCE RAIN IN EXTREME SOUTHEAST PA A FEW HOURS EITHER SIDE OF 8
AM MONDAY. 18Z GEFS WOULD FAVOR SOME LIGHT RAIN IN EASTERN PA
BETWEEN 8 AND 4 PM ON MONDAY. SOME LOCALLY ENHANCED POPS IN NW PA
TOO MONDAY WITH THE MODEST PW SURGE AHEAD OF THE NORTHERN STREAM
FRONTAL SYSTEM. WOULD BE SHRA WITH TSTMS IN NW PA WITH CAPE VALUES
IN THE 600 TO 800JK-1 RANGE. IN EASTERN PA THE RAIN WOULD BE ON
COOLER MORE STABLE EASTERLY FLOW.

THE FRONT AND MOISTURE GET HUNG UP OVER PA TUESDAY. THUS THE
MODELS PRODUCE OVER 800JKG-1 OF CAPE TUESDAY. NO WINDS TO SPEAK
OF. BUT MODEST PROBABILITIES SHOWERS AND THUNDER LATE MORNING INTO
THE EVENING ON TUESDAY.

STILL SOME INSTABILITY TO DEAL WITH IN EASTERN PA WED. A FEW MORE
SHOWERS/TSTMS WITH MODEST CAPE MAINLY BELOW ABOUT 800JKG-1.

WE COOL OFF MONDAY-TUES WITH CLOUDS AND RAIN...EASTERLY FLOW
MONDAY IN EASTERN PA WITH COASTAL SYSTEM (ALBERTO). ALBERTO TO SE
AND AND SHORT WAVE AND FRONT TO NW MAKE MON-TUES BEST RAINFALL
POTENTIAL DAYS. AT THIS TIME LOOKING AT A FEW TENTHS. NOTHING BIG
AS PROBABILITIES OF 0.50 AND 1.00 INCHES STAY TO OUR EAST.

TRIED TO KEEP AS MUCH OF THE LATER PART OF THE WEEK DRY...GIVEN
BUILDING RIDGE ALOFT.

KEY THING IS WITH CLOSE 5880M RIDGE BUILDING IN LATER IN
WEEK...SURGE OF ABOVE NORMAL 850 HPA TEMPS WITH RELATIVELY LOW PW
VALUES SUGGESTING WARMING UP THURSDAY AND WARMER STILL FRIDAY AND
SATURDAY.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
A RIDGE OF HIGH PRESSURE WILL REMAIN NEARLY STATIONARY OVER
PENNSYLVANIA THROUGH SUNDAY...CONTINUING A PERIOD OF VFR
CONDITIONS WITH CLEAR SKIES AND LIGHT WINDS.

EASTERLY FLOW BEGINS TO INCREASE ACROSS THE REGION ON SUNDAY.
CLOUDS INCREASE SUNDAY NIGHT INTO MONDAY AS A DEEP LOW BACKS INTO
THE REGION FROM THE SOUTHEAST. SHOWERY WEATHER RETURNS EARLY
MONDAY WITH MVFR TO IFR CONDITIONS IN LOW CIGS AND VSBY POSSIBLE
IN RAIN SHOWERS ALONG THE LOWER SUSQ TAF SITES /MDT-LNS AND POSS
IPT/.

OUTLOOK...
SUN...VFR WITH A LIGHT...MAINLY EASTERLY WIND.
MON...SCATTERED MVFR CIGS AND VSBYS IN SHOWERS AND ISOLD
THUNDERSTORMS.
MON NIGHT THROUGH WEDNESDAY...MORE WIDESPREAD
REDUCED CIGS AND VSBYS LIKELY IN SHOWERS AND SCTD TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSTM POSS MAINLY SE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...GRUMM
NEAR TERM...FITZGERALD
SHORT TERM...GRUMM
LONG TERM...GRUMM/MARTIN
AVIATION...RXR







AREA FORECAST DISCUSSION

NWS GREENVILLE-SPARTANBURG SC

 946 PM EDT MON MAY 21 2012

.SYNOPSIS...
TROPICAL STORM ALBERTO WILL LINGER OFF THE CAROLINA COAST TONIGHT
BEFORE BEGINNING TO PULL AWAY TO THE NORTHEAST ON TUESDAY. AN UPPER
LEVEL LOW PRESSURE AND ASSOCIATED A COLD FRONT WILL MOVE THROUGH
THE REGION ON TUESDAY. THE LOW PRESSURE WILL STEADILY LIFT NORTHEAST
THROUGH MID WEEK...REPLACED BY BUILDING HIGH PRESSURE AND
UNSEASONABLY WARM TEMPERATURES LATE THIS WEEK THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TUESDAY/...
AS OF 930 PM...ANOTHER UPDATE FOR CONVECTIVE/POP TRENDS THIS
EVENING. THE 18Z NAM WAS CORRECT ON DEPICTING DECENT CONVECTIVE
COVERAGE ALONG AN AXIS OF COVERAGE ALIGN ALONG THE I-77
CORRIDOR...SO I HAVE ADJUSTED POPS WITH THE NAM. WITH PWATS AROUND
1.25" AND VERY SLOW STORM MOTIONS...LOCALIZED HEAVY RAIN AND MINOR
FLOODING ARE POSSIBLE...ESPECIALLY IN URBAN AREAS. THE NAM HAS
CONVECTION LINGERING TILL ABOUT 06Z (2 AM). OTHERWISE...CONVECTION
HAS BEEN DYING OFF ACRS THE REST OF THE CWFA.

TO THE WEST...HEIGHT FALLS AND AN APPROACHING COLD FRONT HAVE AIDED
IN LARGE CLUSTERS OF SLOW-MOVING STORMS ACRS KY/TN. MOST OF THE
ACTIVITY SEEMS TO BE ON A DOWNWARD TREND...BUT LEADING OUTFLOW STILL
TRIGGERING SOME NEW DEVELOPMENT ACRS E TN. SO WILL LEAVE THE CHC
POPS ALONG THE TN LINE FOR THE OVERNIGHT. PLENTY OF DEBRIS
CLOUDINESS EXPECTED OVERNIGHT WITH MIN TEMPS MAINLY IN THE MID 50S
TO LWR 60S.

ON TUE...THE UPPER TROUGH IS FORECAST TO ONLY MOVE MARGINALLY
EASTWARD WITH ITS AXIS PERHAPS REACHING THE MOUNTAINS LATE IN THE
DAY. WEAK UPPER DIFFLUENCE AND THE STALLED SURFACE BOUNDARY SHOULD
BE ENOUGH TO TRIGGER SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS TUE AFTERNOON. A GUIDANCE BLEND PUTS TEMPS NEAR
AVERAGE.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 230 PM MONDAY...MODELS ARE IN FAIR AGREEMENT SLOWING DOWN THE
PROGRESSION OF THE UPPER TROF/LOW CENTER MOVG NE TUE NIGHT-WED BUT
THE WEAK SFC FRONT SHOULD STILL MOVE SLOWLY E OF THE AREA BEFORE
WASHING OUT DURING THE DAY WED. RETURNING LOW LVL S FLOW WILL BRING
MOISTURE OVER THE REGION AND KEEP A CHC OF SCT SHWRS/TSTMS WED
AFTN-EVE...ESP OVER THE MTNS IN AREAS OF BEST UPSLOPE. THE UPPER LOW
MEANDERS OVER THE SE US WED NIGHT-THU WITH A SERIES OF WEAK UPPER
DISTURBANCES ROTATING AROUND IT AND OVER THE AREA...WHILE ENOUGH LOW
LVL MOISTURE REMAINS OVER THE CWA FOR A CONTINUING CHC OF SHWRS AND
TSTMS THU...ESP OVER THE MTNS WITH AFTN HEATING. LOOK FOR TEMPS NEAR
TO SLIGHTLY ABOVE AVG THRU THE PD.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 200 PM MONDAY...THE LATEST MODELS ARE IN GOOD AGREEMENT WITH
THE STRONG UPPER LEVEL RIDGE OF HIGH PRESSURE BUILDING OVER THE
EASTERN CONUS AND REMAIN PREDOMINANT LATE THURSDAY INTO SATURDAY.
EXPECT UNSEASONABLY WARM TEMPERATURES AND MOSTLY DRY CONDITIONS
ACROSS MUCH OF PIEDMONT/VALLEYS DURING THE PERIOD. HOWEVER...A
COMBINATION OF UPSLOPE FLOW(SE TO E) AND DIURNAL INSTABILITY MAY
SUPPORT THE DEVELOPMENT OF AFTERNOON ISOLATED/SCATTERED
THUNDERSTORMS ALONG THE BLUE RIDGE MOUNTAINS EACH DAY. SO HAVE KEPT
SLIGHT CHANCE POPS THERE WITH DRY ELSEWHERE. DAYTIME HIGHS OVER THE
PIEDMONT WILL BE IN THE UPPER 80S THU/FRI AND WARMING INTO THE LOW
90S SATURDAY.

SUNDAY AND MONDAY...CONFIDENCE IS LOW AS THE MODELS SHOW DIFFERENT
SOLUTIONS. THE CANADIAN MODEL SHOWS A CUT OFF LOW FORMING OFF THE
NORTH CAROLINA COAST BY EARLY SUNDAY AND LINGERS INTO MONDAY WHILE
THE GFS AND THE ECMWF SUGGEST A TROPICAL WAVE OVER THE ATLANTIC
OCEAN MOVING WEST INTO THE GA/SC COAST BY SUNDAY. DUE TO THE
TROPICAL MOISTURE INFLUX FROM THE SE AND DIURNAL INSTABILITY...WILL
CARRY SLIGHT CHANCE POPS ACROSS MUCH OF OUR CWA. DAYTIME HIGHS WILL
REMAIN 5-10 DEGREES ABOVE NORMALS SUN/MON.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
AT KCLT...THE LATEST HRRR AND OTHER HIGH-RES GUIDANCE SEEMS TO LINE
UP WITH RADAR TRENDS WITH CONVECTION SLOWLY ROLLING OFF THE BLUE
RIDGE. SOME SHOWERS ARE DEVELOPING ALONG A SEWD-MOVING OUTFLOW BNDRY
WEST OF KCLT. FOR NOW...STILL STICKING WITH PREVIOUS THINKING AND
KEEPING VCSH. BUT IF THE SHOWER GETS MUCH TALLER...MAY NEED A
COR/AMD TO ADD TEMPO TS. OTHERWISE...THINK CONVECTION SHUD OVERALL
WANE THIS EVENING WITH SOME DEBRIS MID-HIGH CLOUDINESS LINGERING
OVERNIGHT. NOT EXPECTING FOG OR STRATUS TUESDAY MORNING (UNLESS THIS
EVENING/S CONVECTION IS MORE WIDESPREAD THAN EXPECTED...IN WHICH
CASE WE WOULD REASSESS). A TROF IS EXPECTED TO BECOME UNSTABLE AND
QUITE ACTIVE TUESDAY AFTN/EVE. ALREADY GOING WITH LIKELY POPS...SO
HAVE PREVAILING TSRA FROM 20Z ONWARD.

ELSEWHERE...DISSIPATING VCSH AT ALL SITES. A STRAY TS CANNOT BE
RULED OUT...BUT CHC TOO LOW FOR TEMPO AT ANY OF THE SITES (EXCEPT AT
KHKY). CONVECTION SHUD WANE OVERALL THIS EVENING WITH LINGERING
MID-HIGH CLOUDINESS OVERNIGHT. GUIDANCE SHOWING SOME FOG IN THE MTN
VALLEYS. THERE HAS BEEN SOME HEAVY RAIN IN THE FRENCH BROAD VALLEY
(BUT NOT AT KAVL AIRFIELD). FOR NOW KEEPING JUST MVFR VSBY AT KAVL.
SOME FOG ALSO POSSIBLE AT KHKY WHERE HEAVY RAIN OCCURRED. ANOTHER
ROUND OF NUMEROUS SHRA AND TSRA EXPECTED TUESDAY AFTN ACRS THE
ENTIRE AREA.

OUTLOOK...SHOWER AND TSTM CHANCES WILL DIMINISH DIURNALLY TUE NIGHT
BUT RE-DEVELOP AGAIN WED AFTERNOON MOST AREAS. DIURNAL THUNDERSTORMS
TOWARD THE END OF THE WEEK WILL BE MORE LIKELY CONFINED TO THE
MOUNTAINS AND FOOTHILLS. EARLY MORNING RESTRICTIONS DUE TO FOG ARE A
GOOD BET MAINLY IN THE MOUNTAIN VALLEYS EACH MORNING.

AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...

WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.

&&

$$
SYNOPSIS...JOH
NEAR TERM...ARK/LG
SHORT TERM...RB
LONG TERM...JOH
AVIATION...ARK







AREA FORECAST DISCUSSION

NWS GREENVILLE-SPARTANBURG SC

 759 PM EDT MON MAY 21 2012

.SYNOPSIS...
TROPICAL STORM ALBERTO WILL LINGER OFF THE CAROLINA COAST TONIGHT
BEFORE BEGINNING TO PULL AWAY TO THE NORTHEAST ON TUESDAY. AN UPPER
LEVEL LOW PRESSURE AND ASSOCIATED A COLD FRONT WILL MOVE THROUGH
THE REGION ON TUESDAY. THE LOW PRESSURE WILL STEADILY LIFT NORTHEAST
THROUGH MID WEEK...REPLACED BY BUILDING HIGH PRESSURE AND
UNSEASONABLY WARM TEMPERATURES LATE THIS WEEK THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TUESDAY/...
AS OF 745 PM...AGAIN MAIN ADJUSTMENTS WERE FOR TRENDS IN CONVECTION.
OTHERWISE...VERY FEW TWEAKS MADE WITH THIS UPDATE.

AS OF 515 PM...TWEAKED THE POP/WX/SKY GRIDS TO MATCH UP WITH
RADAR/SAT TRENDS FOR NEXT FEW HOURS. HIGH-RES MODELS STILL INDICATE
THE BULK OF CONVECTION WILL NOT BE ABLE TO SURVIVE OFF THE BLUE
RIDGE...THANKS TO WEAK SHEAR...LACK OF LLVL CONVERGENCE...AND LOWER
MLCAPE (<500 J/KG ACRS THE UPSTATE). A LITTLE MORE QUESTIONABLE ACRS
THE NW NC PIEDMONT WHERE CAPE MAY BE JUST ENUF FOR A FEW STORMS TO
APPROACH THE CHARLOTTE AREA. SEVERE THREAT STILL LOOKS MARGINAL
GIVEN LOW DCAPE IN THE MTNS AND RELATIVE MOIST PROFILES INVOF THE
FREEZING LEVEL. STORMS SHUD DISSIPATE THIS EVENING.

FOR THE OVERNIGHT...AN UPPER TROUGH WILL SLOWLY APPROACH FROM THE
WEST BY LATE TONIGHT. FALLING HEIGHTS AND WEAK UPSLOPE SHOULD
TRIGGER SCATTERED SHOWERS AND THUNDERSTORMS OVER THE MOUNTAINS
LATE TONIGHT. USED A MOS BLEND FOR TEMPS.

ON TUE...THE UPPER TROUGH IS FORECAST TO ONLY MOVE MARGINALLY
EASTWARD WITH ITS AXIS PERHAPS REACHING THE MOUNTAINS LATE IN THE
DAY. WEAK UPPER DIFFLUENCE AND THE STALLED SURFACE BOUNDARY SHOULD
BE ENOUGH TO TRIGGER SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS TUE AFTERNOON. A GUIDANCE BLEND PUTS TEMPS NEAR
AVERAGE.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 230 PM MONDAY...MODELS ARE IN FAIR AGREEMENT SLOWING DOWN THE
PROGRESSION OF THE UPPER TROF/LOW CENTER MOVG NE TUE NIGHT-WED BUT
THE WEAK SFC FRONT SHOULD STILL MOVE SLOWLY E OF THE AREA BEFORE
WASHING OUT DURING THE DAY WED. RETURNING LOW LVL S FLOW WILL BRING
MOISTURE OVER THE REGION AND KEEP A CHC OF SCT SHWRS/TSTMS WED
AFTN-EVE...ESP OVER THE MTNS IN AREAS OF BEST UPSLOPE. THE UPPER LOW
MEANDERS OVER THE SE US WED NIGHT-THU WITH A SERIES OF WEAK UPPER
DISTURBANCES ROTATING AROUND IT AND OVER THE AREA...WHILE ENOUGH LOW
LVL MOISTURE REMAINS OVER THE CWA FOR A CONTINUING CHC OF SHWRS AND
TSTMS THU...ESP OVER THE MTNS WITH AFTN HEATING. LOOK FOR TEMPS NEAR
TO SLIGHTLY ABOVE AVG THRU THE PD.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 200 PM MONDAY...THE LATEST MODELS ARE IN GOOD AGREEMENT WITH
THE STRONG UPPER LEVEL RIDGE OF HIGH PRESSURE BUILDING OVER THE
EASTERN CONUS AND REMAIN PREDOMINANT LATE THURSDAY INTO SATURDAY.
EXPECT UNSEASONABLY WARM TEMPERATURES AND MOSTLY DRY CONDITIONS
ACROSS MUCH OF PIEDMONT/VALLEYS DURING THE PERIOD. HOWEVER...A
COMBINATION OF UPSLOPE FLOW(SE TO E) AND DIURNAL INSTABILITY MAY
SUPPORT THE DEVELOPMENT OF AFTERNOON ISOLATED/SCATTERED
THUNDERSTORMS ALONG THE BLUE RIDGE MOUNTAINS EACH DAY. SO HAVE KEPT
SLIGHT CHANCE POPS THERE WITH DRY ELSEWHERE. DAYTIME HIGHS OVER THE
PIEDMONT WILL BE IN THE UPPER 80S THU/FRI AND WARMING INTO THE LOW
90S SATURDAY.

SUNDAY AND MONDAY...CONFIDENCE IS LOW AS THE MODELS SHOW DIFFERENT
SOLUTIONS. THE CANADIAN MODEL SHOWS A CUT OFF LOW FORMING OFF THE
NORTH CAROLINA COAST BY EARLY SUNDAY AND LINGERS INTO MONDAY WHILE
THE GFS AND THE ECMWF SUGGEST A TROPICAL WAVE OVER THE ATLANTIC
OCEAN MOVING WEST INTO THE GA/SC COAST BY SUNDAY. DUE TO THE
TROPICAL MOISTURE INFLUX FROM THE SE AND DIURNAL INSTABILITY...WILL
CARRY SLIGHT CHANCE POPS ACROSS MUCH OF OUR CWA. DAYTIME HIGHS WILL
REMAIN 5-10 DEGREES ABOVE NORMALS SUN/MON.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
AT KCLT...THE LATEST HRRR AND OTHER HIGH-RES GUIDANCE SEEMS TO LINE
UP WITH RADAR TRENDS WITH CONVECTION SLOWLY ROLLING OFF THE BLUE
RIDGE. SOME SHOWERS ARE DEVELOPING ALONG A SEWD-MOVING OUTFLOW BNDRY
WEST OF KCLT. FOR NOW...STILL STICKING WITH PREVIOUS THINKING AND
KEEPING VCSH. BUT IF THE SHOWER GETS MUCH TALLER...MAY NEED A
COR/AMD TO ADD TEMPO TS. OTHERWISE...THINK CONVECTION SHUD OVERALL
WANE THIS EVENING WITH SOME DEBRIS MID-HIGH CLOUDINESS LINGERING
OVERNIGHT. NOT EXPECTING FOG OR STRATUS TUESDAY MORNING (UNLESS THIS
EVENING/S CONVECTION IS MORE WIDESPREAD THAN EXPECTED...IN WHICH
CASE WE WOULD REASSESS). A TROF IS EXPECTED TO BECOME UNSTABLE AND
QUITE ACTIVE TUESDAY AFTN/EVE. ALREADY GOING WITH LIKELY POPS...SO
HAVE PREVAILING TSRA FROM 20Z ONWARD.

ELSEWHERE...DISSIPATING VCSH AT ALL SITES. A STRAY TS CANNOT BE
RULED OUT...BUT CHC TOO LOW FOR TEMPO AT ANY OF THE SITES (EXCEPT AT
KHKY). CONVECTION SHUD WANE OVERALL THIS EVENING WITH LINGERING
MID-HIGH CLOUDINESS OVERNIGHT. GUIDANCE SHOWING SOME FOG IN THE MTN
VALLEYS. THERE HAS BEEN SOME HEAVY RAIN IN THE FRENCH BROAD VALLEY
(BUT NOT AT KAVL AIRFIELD). FOR NOW KEEPING JUST MVFR VSBY AT KAVL.
SOME FOG ALSO POSSIBLE AT KHKY WHERE HEAVY RAIN OCCURRED. ANOTHER
ROUND OF NUMEROUS SHRA AND TSRA EXPECTED TUESDAY AFTN ACRS THE
ENTIRE AREA.

OUTLOOK...SHOWER AND TSTM CHANCES WILL DIMINISH DIURNALLY TUE NIGHT
BUT RE-DEVELOP AGAIN WED AFTERNOON MOST AREAS. DIURNAL THUNDERSTORMS
TOWARD THE END OF THE WEEK WILL BE MORE LIKELY CONFINED TO THE
MOUNTAINS AND FOOTHILLS. EARLY MORNING RESTRICTIONS DUE TO FOG ARE A
GOOD BET MAINLY IN THE MOUNTAIN VALLEYS EACH MORNING.

AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...

WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.

&&

$$
SYNOPSIS...JOH
NEAR TERM...ARK/LG
SHORT TERM...RB
LONG TERM...JOH
AVIATION...ARK







AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA

NWS SIOUX FALLS SD

 1104 PM CDT MON MAY 21 2012

.DISCUSSION.../ISSUED AT 851 PM CDT/
LATEST RAP SHOWS 500-1000 J/KG INSTABILITY DEVELOPING LATE TONIGHT
FOR PARCELS ORIGINATING ABOVE 800 MB. BELOW THAT LAYER THERE IS
FAIRLY STRONG THETA-E ADVECTION TO PRODUCE SOME LIFT. WHAT IS
LACKING IS ANY TYPE OF STRONG FRONT OR EVEN UPPER LEVEL FEATURE TO
ENHANCE LIFT ON THE MESOSCALE.  NONETHELESS...WHILE IT IS LIKELY
UNDERDOING THE CONVECTIVE INHIBITION...EXPECT THAT AT LEAST ISOLATED
THUNDERSTORMS WILL BEGIN TO DEVELOP AROUND MIDNIGHT WEST OF THE
JAMES RIVER AND MOVE EAST THROUGH THE NIGHT...REACHING I-29 BY 09Z
AND MOST OF SW MN AND NW IA BY 12Z. DID CONSIDER ADDING A SLIGHT
CHANCE FOR EARLY TOMORROW MORNING EAST OF I-29 BUT WITH CHANCE LESS
THAN 20 PERCENT DECIDED TO FORGO MENTION AT THIS POINT.
OTHERWISE...ONLY OTHER CHANGE WAS TO INCREASE WINDS ALONG AND EAST
OF THE BUFFALO RIDGE. HI-RES WRF-ARW SHOWS WINDS SUSTAINED OVER 20
MPH LATE TONIGHT WITH GUSTS OVER 30 MPH POSSIBLE BY DAWN. THIS WILL
ALSO ALLOW TEMPS TO RISE A COUPLE OF DEGREES LATE TONIGHT SO RAISED
LOWS INTO THE LOWER 60S. UPDATED ZFP/PFM AND GRIDS OUT.

&&

.AVIATION.../FOR THE 06Z TAF ISSUANCE/
VFR CONDITIONS WILL CONTINUE THROUGH THE TAF FORECAST PERIOD.
ELEVATED SHOWERS OR THUNDERSTORMS MAY DEVELOP PRIOR TO 14Z THIS
MORNING...HOWEVER EXPECTED ISOLATED COVERAGE PRECLUDES MENTION IN
TAFS AT THIS TIME. INCREASING SOUTH WINDS WILL CREATE ADDITIONAL
AVIATION CONCERN ON TUESDAY...WITH GUSTS GREATER THAN 25KT LIKELY
AFTER 14Z THROUGH THE END OF THE PERIOD. STRONGEST WINDS SHOULD
DIMINISH BY 23/01Z...THOUGH 45-55KT LOW LEVEL JET ABOVE 1100FT AGL
COULD CREATE LOW LEVEL WIND SHEAR AFTER SUNSET TUESDAY EVENING. WILL
NOT INCLUDE IN TAFS AT THIS TIME...BUT MAY NEED TO BE ADDED IN
FUTURE ISSUANCES.

&&

.PREV DISCUSSION.../ISSUED AT 315 PM CDT/
MID LEVEL CLOUDS ALONG AND EAST OF I29 WILL CONTINUE TO PUSH EAST
THROUGH THIS EVENING WITH PARTLY CLOUDY SKIES EXPECTED MOST OF THE
NIGHT. WILL KEEP A VERY SMALL CHANCE FOR THUNDERSTORMS LATE TONIGHT
AS LOW LEVEL JET INCREASES AHEAD OF ELEVATED INSTABILITY WEST OF I29
AFTER 06Z. NOT ALL THAT CONFIDENT ANYTHING WILL FIRE UP SO ONLY WILL
HAVE 20% POPS AT MOST. SOUTHERLY WINDS WILL ALSO HOLD TEMPERATURES
UP TONIGHT WITH LOWS IN THE MID 50S TO LOWER 60S.

WHILE THERE IS NO MAGIC LINE ON IT AT DAYBREAK...THE CHANCE OF ANY
LINGERING STORMS IN OUR FAR EAST EARLY TUESDAY MORNING SEEMS LOW
ENOUGH TO KEEP MENTION OF OUT FOR TUESDAY...CONSIDERING CHANCE
TONIGHT IS SO SMALL AND THE WARMING AIR SHOULD BE CAPPED. OTHERWISE
A FEW CLOUDS SHOULD BE MOSTLY HIGH AND LEAD TO A MOSTLY SUNNY WARM
AND VERY WINDY DAY. IT HAS BEEN PLAIN FOR THREE DAYS THAT SOUTHERLY
WINDS WILL BE STRONG AND THAT CONTINUES...WITH GUIDANCE AS USUAL
UNDERDOING EXPECTED SURFACE WINDS. WINDS SHOULD MAKE THE 30 MPH
SUSTAINED CRITERIA OR STRONGER OVER ALL OF THE FORECAST AREA SO WILL
GO WITH A WIND ADVISORY 15Z TO 01Z/10 AM TO 8 PM. HIGH TEMPERATURES
GUIDANCE SEEMS ONLY A LITTLE NOT QUITE WARM ENOUGH WITH 80S TO SOME
LOWER 90S WEST.

COLD FRONT ADVANCES INTO FORECAST AREA TUESDAY NIGHT AND WILL KEEP A
CHANCE OF STORMS AS FRONT ADVANCES...LEAVING OUT PART OF NORTHWEST
IA SOUTHEAST OF SUX TO MJQ LINE. THE ADVANCE CONTINUES WEDNESDAY
WITH THE FRONT DEFINITELY SLOWING. WILL TEMPORARILY DECREASE THE
STORM THREAT WEST WEDNESDAY BEFORE PICKING IT UP AGAIN WEDNESDAY
NIGHT AS ANOTHER WAVE APPROACHES...LIKELY POPS LOOK GOOD FOR THE
EAST FOR WEDNESDAY NIGHT. COOLING AND CLOUDS WILL COOL TEMPERATURES
WEDNESDAY FROM TUESDAY EXCEPT IT WILL STILL BE IN THE WARM 80S
SOUTHEAST OF SUX/SPW LINE. WAVE PULLING OUT TO THE NORTHEAST SHOULD
SLOWLY DECREASE THE RAIN THREAT WEDNESDAY NIGHT AND THURSDAY...AND
ON A CLOSE CALL WILL LEAVE MENTION OUT ALTOGETHER FOR FRIDAY GIVEN
SURFACE AND LOW LEVEL RIDGING BEHIND FRONT. TEMPERATURES OF COURSE
WILL BE COOLER DURING THIS TIME.

RIDGING AND ASSOCIATED WARMING SHOULD BRING A THREAT OF STORMS OVER
THE WEEKEND ALONG WITH WARM AND MORE HUMID CONDITIONS. MODELS
ESPECIALLY THE ECMWF ARE FURTHER EAST WITH THE RIDGING THAN THEY
WERE YESTERDAY WHICH WILL MEAN LESS CAPPING AND ALLOWING THE NEXT
SYSTEM TO GET CLOSE. WILL GO WITH THE CURRENT MODEL RUNS AND START
TO DECREASE RAIN CHANCES AGAIN MONDAY ALONG WITH THE RETURN OF
COOLING.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
IA...WIND ADVISORY FROM 10 AM TO 8 PM CDT TUESDAY FOR IAZ001>003-
     012>014-020>022-031-032.

MN...WIND ADVISORY FROM 10 AM TO 8 PM CDT TUESDAY FOR MNZ071-072-080-
     081-089-090-097-098.

NE...WIND ADVISORY FROM 10 AM TO 8 PM CDT TUESDAY FOR NEZ013-014.

SD...WIND ADVISORY FROM 10 AM TO 8 PM CDT TUESDAY FOR SDZ038>040-050-
     052>071.

&&

$$







AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA

NWS SIOUX FALLS SD

 851 PM CDT MON MAY 21 2012

.DISCUSSION.../ISSUED AT 851 PM CDT/
LATEST RAP SHOWS 500-1000 J/KG INSTABILITY DEVELOPING LATE TONIGHT
FOR PARCELS ORIGINATING ABOVE 800 MB. BELOW THAT LAYER THERE IS
FAIRLY STRONG THETA-E ADVECTION TO PRODUCE SOME LIFT. WHAT IS
LACKING IS ANY TYPE OF STRONG FRONT OR EVEN UPPER LEVEL FEATURE TO
ENHANCE LIFT ON THE MESOSCALE.  NONETHELESS...WHILE IT IS LIKELY
UNDERDOING THE CONVECTIVE INHIBITION...EXPECT THAT AT LEAST ISOLATED
THUNDERSTORMS WILL BEGIN TO DEVELOP AROUND MIDNIGHT WEST OF THE
JAMES RIVER AND MOVE EAST THROUGH THE NIGHT...REACHING I-29 BY 09Z
AND MOST OF SW MN AND NW IA BY 12Z. DID CONSIDER ADDING A SLIGHT
CHANCE FOR EARLY TOMORROW MORNING EAST OF I-29 BUT WITH CHANCE LESS
THAN 20 PERCENT DECIDED TO FORGO MENTION AT THIS POINT.
OTHERWISE...ONLY OTHER CHANGE WAS TO INCREASE WINDS ALONG AND EAST
OF THE BUFFALO RIDGE. HI-RES WRF-ARW SHOWS WINDS SUSTAINED OVER 20
MPH LATE TONIGHT WITH GUSTS OVER 30 MPH POSSIBLE BY DAWN. THIS WILL
ALSO ALLOW TEMPS TO RISE A COUPLE OF DEGREES LATE TONIGHT SO RAISED
LOWS INTO THE LOWER 60S. UPDATED ZFP/PFM AND GRIDS OUT.

&&

.AVIATION.../FOR THE 00Z TAF ISSUANCE/
VFR CONDITIONS WILL CONTINUE THROUGH THE TAF FORECAST PERIOD.
ELEVATED SHOWERS OR THUNDERSTORMS MAY DEVELOP AFTER 06Z EAST OF THE
JAMES RIVER VALLEY...HOWEVER EXPECTED ISOLATED COVERAGE PRECLUDES
MENTION IN KFSD/KSUX TAFS AT THIS TIME. INCREASING SOUTH WINDS WILL
CREATE ADDITIONAL AVIATION CONCERN ON TUESDAY...WITH GUSTS GREATER
THAN 25KT LIKELY AFTER 14Z THROUGH THE END OF THE PERIOD.

&&

.PREV DISCUSSION.../ISSUED AT 315 PM CDT/
MID LEVEL CLOUDS ALONG AND EAST OF I29 WILL CONTINUE TO PUSH EAST
THROUGH THIS EVENING WITH PARTLY CLOUDY SKIES EXPECTED MOST OF THE
NIGHT. WILL KEEP A VERY SMALL CHANCE FOR THUNDERSTORMS LATE TONIGHT
AS LOW LEVEL JET INCREASES AHEAD OF ELEVATED INSTABILITY WEST OF I29
AFTER 06Z. NOT ALL THAT CONFIDENT ANYTHING WILL FIRE UP SO ONLY WILL
HAVE 20% POPS AT MOST. SOUTHERLY WINDS WILL ALSO HOLD TEMPERATURES
UP TONIGHT WITH LOWS IN THE MID 50S TO LOWER 60S.

WHILE THERE IS NO MAGIC LINE ON IT AT DAYBREAK...THE CHANCE OF ANY
LINGERING STORMS IN OUR FAR EAST EARLY TUESDAY MORNING SEEMS LOW
ENOUGH TO KEEP MENTION OF OUT FOR TUESDAY...CONSIDERING CHANCE
TONIGHT IS SO SMALL AND THE WARMING AIR SHOULD BE CAPPED. OTHERWISE
A FEW CLOUDS SHOULD BE MOSTLY HIGH AND LEAD TO A MOSTLY SUNNY WARM
AND VERY WINDY DAY. IT HAS BEEN PLAIN FOR THREE DAYS THAT SOUTHERLY
WINDS WILL BE STRONG AND THAT CONTINUES...WITH GUIDANCE AS USUAL
UNDERDOING EXPECTED SURFACE WINDS. WINDS SHOULD MAKE THE 30 MPH
SUSTAINED CRITERIA OR STRONGER OVER ALL OF THE FORECAST AREA SO WILL
GO WITH A WIND ADVISORY 15Z TO 01Z/10 AM TO 8 PM. HIGH TEMPERATURES
GUIDANCE SEEMS ONLY A LITTLE NOT QUITE WARM ENOUGH WITH 80S TO SOME
LOWER 90S WEST.

COLD FRONT ADVANCES INTO FORECAST AREA TUESDAY NIGHT AND WILL KEEP A
CHANCE OF STORMS AS FRONT ADVANCES...LEAVING OUT PART OF NORTHWEST
IA SOUTHEAST OF SUX TO MJQ LINE. THE ADVANCE CONTINUES WEDNESDAY
WITH THE FRONT DEFINITELY SLOWING. WILL TEMPORARILY DECREASE THE
STORM THREAT WEST WEDNESDAY BEFORE PICKING IT UP AGAIN WEDNESDAY
NIGHT AS ANOTHER WAVE APPROACHES...LIKELY POPS LOOK GOOD FOR THE
EAST FOR WEDNESDAY NIGHT. COOLING AND CLOUDS WILL COOL TEMPERATURES
WEDNESDAY FROM TUESDAY EXCEPT IT WILL STILL BE IN THE WARM 80S
SOUTHEAST OF SUX/SPW LINE. WAVE PULLING OUT TO THE NORTHEAST SHOULD
SLOWLY DECREASE THE RAIN THREAT WEDNESDAY NIGHT AND THURSDAY...AND
ON A CLOSE CALL WILL LEAVE MENTION OUT ALTOGETHER FOR FRIDAY GIVEN
SURFACE AND LOW LEVEL RIDGING BEHIND FRONT. TEMPERATURES OF COURSE
WILL BE COOLER DURING THIS TIME.

RIDGING AND ASSOCIATED WARMING SHOULD BRING A THREAT OF STORMS OVER
THE WEEKEND ALONG WITH WARM AND MORE HUMID CONDITIONS. MODELS
ESPECIALLY THE ECMWF ARE FURTHER EAST WITH THE RIDGING THAN THEY
WERE YESTERDAY WHICH WILL MEAN LESS CAPPING AND ALLOWING THE NEXT
SYSTEM TO GET CLOSE. WILL GO WITH THE CURRENT MODEL RUNS AND START
TO DECREASE RAIN CHANCES AGAIN MONDAY ALONG WITH THE RETURN OF
COOLING.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
IA...WIND ADVISORY FROM 10 AM TO 8 PM CDT TUESDAY FOR IAZ001>003-
     012>014-020>022-031-032.

MN...WIND ADVISORY FROM 10 AM TO 8 PM CDT TUESDAY FOR MNZ071-072-080-
     081-089-090-097-098.

NE...WIND ADVISORY FROM 10 AM TO 8 PM CDT TUESDAY FOR NEZ013-014.

SD...WIND ADVISORY FROM 10 AM TO 8 PM CDT TUESDAY FOR SDZ038>040-050-
     052>071.

&&

$$











AREA FORECAST DISCUSSION

NWS GREEN BAY WI

 1037 PM CDT MON MAY 21 2012

UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE

.SHORT TERM...TONIGHT AND TUESDAY.

LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SURFACE HIGH
PRESSURE STRETCHING FROM TEXAS TO WESTERN ONTARIO THIS AFTERNOON.
MID AND HIGH CLOUDS ARE ADVANCING TO THE EAST OVER THE NORTHERN
PLAINS AND INTO THE NORTHERN MISSISSIPPI VALLEY...BUT DRY AIR ACROSS
THE REGION IS DISSIPATING THE CLOUDS ON THE LEADING EDGE.  MUCH
COOLER AND DRIER CONDITIONS ARE PRESENT ACROSS THE REGION TODAY WITH
ONLY SOME DIURNAL CU DEVELOPING OVER EASTERN WISCONSIN.  WITH A DRY
AIRMASS IN PLACE...TEMPS AND FROST HEADLINES ARE THE MAIN FORECAST
CONCERNS.

TONIGHT...HIGH PRESSURE WILL BE DRAPED ACROSS THE REGION
TONIGHT...WHICH WILL KEEP A DRY AIRMASS IN PLACE BELOW 700MB.
THETAE ADVECTION ABOVE THIS LEVEL MAY BRING FEW/SCT CLOUDS FROM THE
NORTHERN MISSISSIPPI VALLEY INTO NORTH-CENTRAL WISCONSIN...THOUGH
IMPACT ON TEMPS SHOULD BE MINIMAL.  GOOD RADIATIVE COOLING
CONDITIONS WILL SUPPORT TEMPS FALLING FROM THE MID 30S NORTH TO LOW
40S SOUTH.  TEMPS WILL FALL LOCALLY COOLER WITHIN THE SANDY SOIL
AREAS OF NORTH-CENTRAL AND FAR NORTHEAST WISCONSIN WHERE TEMPS MAY
EVEN FALL TO THE UPPER 20S.  WILL HOIST A FROST ADVISORY NORTH OF A
LINCOLN TO NORTHERN MARINETTE LINE.

TUESDAY...HIGH PRESSURE WILL DRIFT FROM EASTERN WISCONSIN TO THE
CENTRAL GREAT LAKES.  RELATIVELY THIN MID AND HIGH CLOUDS WILL MOVE
OVERHEAD DURING THE COURSE OF THE DAY...WHICH SHOULD KEEP SKY
CONDITIONS MOSTLY CLEAR TO PARTLY CLOUDY.  A WARM FRONT WILL BE
STRETCHED ALONG THE US-CANADIAN BORDER AND PRECIP CHANCES SHOULD
REMAIN NORTHWEST OF THE FORECAST AREA.  925MB TEMPS ARE A DEGREE OR
TWO WARMER TOMORROW...SO WILL GO WITH HIGHS IN THE LOW TO MID 70S.

.LONG TERM...TUESDAY NIGHT THROUGH NEXT MONDAY.
MAIN FORECAST CHALLENGE FOR THIS PERIOD IS TRYING TO ADD SOME
RESOLUTION TO THE VARIOUS PCPN CHANCES STARTING LATER THIS
WEEK...ALONG WITH ADJUSTING ANY MAX TEMPS DUE TO VARIOUS SOLUTIONS
OF BOUNDARY LOCATIONS.

SURFACE HIGH PRESSURE WITH UPPER RIDGE WILL CONTINUE TO PROVIDE
QUIET WEATHER TO THE AREA TUESDAY NIGHT INTO THURSDAY FOR MOST
LOCATIONS. CONVECTION WILL BE CONFINED TO THE NORTHWEST STATES
AND NORTHERN PLAINS AS A BROAD UPPER TROUGH SETTLES INTO THIS
AREA. WILL CONFINE ANY SMALL PCPN MENTION AND MORE CLOUDS WEST OF
A RHI TO AUW LINE DUE TO THE POSSIBILITY OF ANY NORTHERN PLAINS
CONVECTION BRUSHING NORTHWEST WISCONSIN.

WILL THEN FOCUS ON THE HIGHER END CHC POPS FOR THE THURSDAY NIGHT
INTO FRIDAY MORNING PERIOD AS A SHORT WAVE SLIDES OVER THE STATE
WITH SURFACE FROPA. WILL DIMINISH PCPN LATER FRIDAY BUT STILL
UNKNOWN HOW FAR SOUTH THE FRONT WILL SETTLE AS THE UPPER FLOW
REMAINS SOUTHWEST. WILL ALSO KEEP CHC POPS GOING DUE TO A BAROCLINIC
ZONE LINGERING OVER THE STATE IN THE COOL SECTOR. WITH COOLER
TEMPS AND LITTLE INSTABILITY...DOWNPLAYED TSRA MENTION TO SHOWERS
FRIDAY NIGHT. INSTABILITY INCREASES AGAIN LATER SATURDAY.  MEDIUM
MODEL RUNS BEGINNING TO SHOW SOME CONSENSUS OF THE FRONTAL
BOUNDARY LIFTING NORTH AGAIN IN RESPONSE TO THE WESTERN STATES
TROUGH DEEPENING AND EASTERN STATES UPPER RIDGE BUILDING. AGAIN
ANOTHER WAVE WITH FRONTAL SYSTEM ATTEMPTS TO SLIDE OVER THE REGION
LATER SUNDAY NIGHT INTO MONDAY FOR A FIRST STAB AT THE TIMING.

WENT WITH COOLER TEMPS SATURDAY WITH LAGGING BAROCLINIC ZONE BUT
WARMER SUNDAY MAX TEMPS AS UPPER HEIGHTS BUILD AND THE FRONT LIFTS
NORTH AS A WARM FRONT.
&&

.AVIATION...FOR 06Z TAF ISSUANCE. VFR CONDITIONS EXPECTED THROUGH
THE NEXT 24 HRS AS SFC RIDGE CROSSES THE AREA AND SLIDES OFF TO
THE SE. LLWS WL START TO INCR TOMORROW NIGHT...BUT NOT YET TO THE
POINT WHERE IT WL REQUIRE INCLUSION IN THE TAFS.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY FROM 2 AM TO 7 AM CDT TUESDAY FOR WIZ005-010>013-
018-019-021.
&&

$$









AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 638 PM CDT MON MAY 21 2012

.SHORT TERM...TONIGHT THROUGH THURSDAY
325 PM CDT MON MAY 21 2012

MAIN FORECAST CONCERNS ARE FROST POTENTIAL TONIGHT AND PRECIPITATION
CHANCES AS WELL AS TEMPERATURES WEDNESDAY INTO THURSDAY.

CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED RIDGING FROM THE DESERT SOUTHWEST INTO ALBERTA AND WEAK
TROUGHING OVER THE WESTERN GREAT LAKES REGION. HIGH PRESSURE
DOMINATES AT THE SURFACE ON THE BACK SIDE OF THE WEAK TROUGHING...
ENCOMPASSING THE ENTIRE FORECAST AREA. DRY AIR...SEEN ON THE 12Z
MPX...GRB AND DVN SOUNDINGS HAS RESULTED IN A SUNNY DAY ACROSS THE
FORECAST AREA. MIXING UP THROUGH 850MB WHERE TEMPS ARE AROUND 6C HAS
YIELDED TEMPERATURES MAINLY IN THE 70S...AND DEWPOINTS MOSTLY DOWN
INTO THE LOW TO MID 30S. TO THE WEST...AN AREA OF MID LEVEL CLOUDS
HAVE BEEN EXPANDING ACROSS NORTH DAKOTA AND INTO WESTERN MINNESOTA.
THESE CLOUDS ARE IN RESPONSE TO WARM ADVECTION AND MOISTURE RETURN
ON THE BACK SIDE OF THE SURFACE HIGH AND AHEAD OF THE UPPER RIDGE
AXIS. THERE WAS A LITTLE LIGHT SHOWER ACTIVITY ON THE WESTERN SIDE
OF THE CLOUDS...ASSOCIATED WITH 305 K ISENTROPIC LIFT...BUT THIS HAS
SINCE DISSIPATED. 12Z SOUNDINGS SHOWED MUCH WARMER AIR OVER THE
DAKOTAS...WITH 850MB TEMPS OF 10-15C ON AVERAGE WITH RAPID CITY AT
19C.

TONIGHT AND TUESDAY...UPPER RIDGING OVER THE NORTHERN ROCKIES WILL
SHIFT EAST INTO THE FORECAST AREA ON TUESDAY...PUSHED ALONG BY
TROUGHING CURRENTLY OFF THE PACIFIC NORTHWEST MOVING INLAND. IN
RESPONSE...A SURFACE LOW DEEPENS ACROSS THE DAKOTAS...INCREASING THE
WARM ADVECTION DOWNSTREAM INTO THE FORECAST AREA. WITH THIS WARM
ADVECTION WE SHOULD SEE SOME OF THOSE MID CLOUDS OVER WESTERN
MINNESOTA MOVE ACROSS. TRENDS IN MODEL RH FIELDS SUGGEST SOME
DISSIPATION OF THE MID CLOUDS AS THEY PUSH EAST...ESPECIALLY DURING
THE DAY TUESDAY. THIS MATCHES THE PREVIOUS FORECAST. IN ADDITION...
IT APPEARS MOST OF THE MID CLOUDS WILL STAY WEST OF THE MISSISSIPPI
RIVER TONIGHT. THIS IS CRITICAL BECAUSE THE SURFACE RIDGE SHOULD BE
CENTERED OVER WISCONSIN MUCH OF TONIGHT...LEADING TO FAVORABLE
RADIATIONAL COOLING CONDITIONS. SINCE BLACK RIVER FALLS AND SPARTA
DROPPED INTO THE LOW TO MID 30S LAST NIGHT...SEE NO REASON WHY THAT
WILL NOT HAPPEN AGAIN. THIS MEANS THAT OUR TYPICAL WISCONSIN COLD
SPOTS COULD SEE SOME FROST. NOT ENOUGH OF AN EXPANSIVE AREA OF COLD
TEMPS IS FORECAST TO WARRANT A FROST ADVISORY...THOUGH. WEST OF THE
MISSISSIPPI RIVER...INCREASING WINDS SHOULD ALLOW TEMPERATURES TO
STAY WARMER THERE. WITH INCREASING SUNSHINE AND SOUTHERLY WINDS ON
TUESDAY...AS WELL AS 850MB TEMPS CLIMBING TO AROUND 10C BY
18Z...SHOULD ALLOW FOR HIGHS WELL INTO THE 70S. WARMEST TEMPS LIKELY
WEST.

TUESDAY NIGHT AND WEDNESDAY...THE UPPER TROUGHING OVER THE NORTHWEST
U.S. IS PROGGED TO DEEPEN DURING THIS PERIOD. A FAIRLY POTENT
SHORTWAVE EJECTING OUT OF THIS TROUGH THROUGH THE DAKOTAS WILL CAUSE
THE LOW PRESSURE AREA THERE TO LIFT INTO NORTHWEST ONTARIO BY 00Z
THURSDAY. ITS ASSOCIATED COLD FRONT APPEARS TO BE TRENDING
SLOWER...NOW ONLY REACHING WESTERN MINNESOTA BY 00Z THURSDAY. THE
ECMWF HAS BEEN SUGGESTING THIS FOR QUITE AWHILE. ONLY MODEL THAT HAS
THE FRONT APPROACHING THE FORECAST AREA IS THE 21.12Z NAM...AND EVEN
IT HAS TRENDED SLOWER FROM ITS PREVIOUS RUNS. THEREFORE...HAVE
CONSIDERED THE NAM A FAST OUTLIER. ANY CONVECTION IS LIKELY TO BE
HIGHLY TIED TO THE FRONT...GIVEN CAPPING PRESENT IN THE WARM SECTOR
AHEAD OF IT. THEREFORE...HAVE DRIED OUT MUCH OF THE FORECAST EXCEPT
FOR A SMALL AREA IN SOUTHEAST MINNESOTA WHICH IS CLOSEST TO THE
FRONTAL BOUNDARY. THESE SMALL CHANCES MAY BE ABLE TO BE PULLED IN
LATER FORECASTS. A BREEZY SOUTH WIND WILL HELP KEEP TEMPERATURES UP
TUESDAY NIGHT INTO THE 50S IN MOST LOCATIONS. SOME OF SOUTHEAST MN
MAY NOT DROP BELOW 60...MEANWHILE THE COLD SPOTS OF WISCONSIN COULD
DECOUPLE AND DROP INTO THE UPPER 40S. MUCH WARMER 850MB TEMPS ARE
PROGGED FOR WEDNESDAY...ON THE ORDER OF 16-18C. NORMALLY THIS COULD
PRODUCE HIGHS OF 85 TO 90. HOWEVER...THERE IS INCREASING CIRRUS
THROUGH THE DAY TO TEMPER HIGHS SOMEWHAT.

WEDNESDAY NIGHT AND THURSDAY...ANOTHER SURFACE LOW IS PROGGED TO
FORM OVER SOUTHEAST COLORADO LATE WEDNESDAY. A POTENT SHORTWAVE
EJECTING OUT OF THE DEEPENING WESTERN TROUGH WILL LIFT THIS LOW
NORTHEAST...RIDING UP THE COLD FRONT AND CROSSING CENTRAL MINNESOTA
ON THURSDAY. THE 21.12Z GFS/UKMET BOTH DEPICT SOME QPF WEDNESDAY
NIGHT OVER WISCONSIN...BUT THESE SEEM ODD GIVEN OUR FORECAST AREA IS
UNDERNEATH THE MAIN MOISTURE TRANSPORT STREAM WITHOUT MOISTURE
CONVERGENCE...AS WELL AS CAPPING ALOFT TO ELEVATED CONVECTION.
THEREFORE...FOR WEDNESDAY NIGHT...KEPT ALL PRECIPITATION CHANCES
OVER FAR NORTHWEST SECTIONS OF THE FORECAST AREA. THESE CHANCES ARE
STILL LOW...20-30...BECAUSE THE FRONTOGENETICAL ZONE ASSOCIATED WITH
THE COLD FRONT LOOKS TO STAY ACTIVE ALONG AND NORTHWEST OF
IT...WHICH KEEPS THE BULK OF THE PRECIPITATION MORE FROM SOUTHWEST
MINNESOTA INTO THE DULUTH AREA. BETTER SHOT EXISTS FOR THE COLD
FRONT TO COME IN ON THURSDAY...IN THIS CASE ASSOCIATED WITH THE NEW
LOW COMING UP. THE 21.12Z GFS REMAINS THE FASTEST MODEL TO DO
SO...WITH THE ECMWF AND ESPECIALLY GEM SUGGESTING SLOWER. LEANED
TOWARDS THE SLOWER PASSAGE...WHICH KEEPS ALL PRECIPITATION CHANCES
OVER THE NORTHWEST HALF OF THE FORECAST AREA. TEMPERATURES BOTH
WEDNESDAY NIGHT AND ESPECIALLY THURSDAY HAVE BEEN WARMED UP...DUE TO
THE SLOWER FRONTAL PASSAGE AND MAINTAINING A LONGER PERIOD OF BREEZY
SOUTH WINDS. THURSDAY COULD TOUCH 90...ESPECIALLY IN THE SOUTHEAST
WHERE MORE SUN IS PRESENT TO COMBINE WITH 850MB TEMPS UP POSSIBLY
NEAR 20C.

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY
325 PM CDT MON MAY 21 2012

MAIN FORECAST CONCERNS ARE ON PRECIPITATION CHANCES AND WHEN THE
HEAT UP WILL COME.

MODELS ARE BECOMING IN MUCH BETTER AGREEMENT ON THE LONG TERM
FORECAST...SO CONFIDENCE IS INCREASING ON WHAT WILL HAPPEN. IN
GENERAL...TROUGHING LOOKS TO REMAIN IN THE WESTERN U.S....
INTENSIFYING BY SATURDAY MORNING. WITH THE DEEPENING TROUGH OUT
WEST...THE RESPONSE IS TO BUILD SOME PRETTY STRONG RIDGING TO THE
EAST. THEREFORE...AFTER WHAT LOOKS TO BE A COLD FRONTAL PASSAGE
THURSDAY NIGHT...THAT COLD FRONT WILL NOT BE ABLE TO DROP TOO FAR
SOUTH. MAINTAINED SOME CHANCES OF SHOWERS AND THUNDERSTORMS FOR
THURSDAY NIGHT...AND THESE MAY NEED TO BE INCREASED OVER WESTERN
SECTIONS WITH A SHORTWAVE PROGGED TO COME OUT. IN FACT...IF THE
21.12Z ECMWF/GEM ARE CORRECT...SOME OF THE STORMS THURSDAY NIGHT
COULD BE SEVERE. WESTERN SECTIONS OF THE AREA LOOK TO GET A BREAK
FROM PRECIPITATION ON FRIDAY WITH THE FRONT PASSED...BUT STILL
MAINTAINED A CHANCE ELSEWHERE SINCE THE FRONT IS STILL MOVING
THROUGH. DEFINITELY COOLER ON FRIDAY BEHIND THE FRONT...BUT STILL
SEASONABLE. FRONT SHOULD LAY UP IN SOUTHERN IOWA FRIDAY NIGHT AND
THEN BEGIN TO RETREAT NORTH AS A WARM FRONT AS THE UPPER RIDGE
STRENGTHENS. MOISTURE TRANSPORT NORTH OF THE FRONT COULD YIELD
CONVECTION FRIDAY NIGHT THROUGH SATURDAY. CANNOT RULE OUT SOME OF
THIS BEING SEVERE TOO. 850MB TEMPS CLIMB TO 20C OR HIGHER SOUTH OF
THE FRONT...WHICH MEANS ON SATURDAY THERE IS POTENTIAL FOR A 20
DEGREE OR MORE SPREAD ACROSS THE FORECAST AREA.

MODELS AGREE THAT THE WESTERN TROUGH BEGINS EJECTING OUT SATURDAY
NIGHT...ALLOWING THE RIDGE AND WARM SECTOR TO BUILD OVER THE
FORECAST AREA. THIS MEANS THE CONVECTION SHOULD SLOWLY SHIFT
NORTH...ALLOWING FOR HEAT AND LIKELY SOME HUMIDITY TO MOVE IN.
RAISED HIGHS ON SUNDAY TO THE MID 80S TO NEAR 90...BUT FURTHER
INCREASES COULD BE NEEDED. SAME GOES FOR LOWS SATURDAY NIGHT AND
SUNDAY NIGHT WHERE POTENTIAL EXISTS FOR TEMPERATURES TO NOT DIP
BELOW 70. LAST ISSUE IS A COLD FRONT PROGGED TO COME AT THE AREA FOR
SUNDAY NIGHT AND MONDAY...ASSOCIATED WITH THE EJECTING WESTERN
TROUGH. THE GFS IS THE FASTEST ON THIS FRONT...WHEREAS THE 21.12Z
ECMWF HAS SLOWED DOWN FROM ITS PREVIOUS RUN. FOR NOW HAVE FOLLOWED A
CONSENSUS AND INCLUDED 20-40 PERCENT CHANCES FOR SUNDAY NIGHT AND
MONDAY. HOWEVER...WOULD NOT BE SURPRISED IF THE SLOWER FRONTAL
TIMING PANS OUT...RESULTING IN A WARMER AND DRIER FORECAST.

IN SUMMARY...SOME POTENTIAL FOR SEVERE STORMS THURSDAY NIGHT AND
FRIDAY NIGHT/SATURDAY...THEN HEATING UP FOR THE END OF MEMORIAL DAY
WEEKEND.

&&

.AVIATION...TONIGHT AND TUESDAY
636 PM CDT MON MAY 21 2012

HIGH PRESSURE WILL MOVE EAST INTO EASTERN WISCONSIN TONIGHT. AS
THIS OCCURS...THE WINDS WILL SHIFT TO THE SOUTH AND THEN INCREASE
ON TUESDAY MORNING AS THE PRESSURE GRADIENT TIGHTENS ON THE BACK
SIDE OF THE HIGH PRESSURE. AS DIURNAL MIXING OCCURS...THE WIND
GUSTS ACROSS SOUTHEAST MINNESOTA WILL CLIMB INTO THE 20 TO 30 KNOT
RANGE...AND 15 TO 25 KNOTS ACROSS WESTERN WISCONSIN.

OTHER THAN OCCASIONALLY BOUTS OF SCATTERED 10-20K CLOUDS...SKIES
WILL BE GENERALLY CLEAR.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
325 PM CDT MON MAY 21 2012

WI...NONE.
MN...NONE.
IA...NONE.

&&

$$

SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE







AREA FORECAST DISCUSSION...UPDATED

NWS GREEN BAY WI

 557 PM CDT SUN MAY 20 2012

.UPDATE...STORMS OVER FAR NE WI STILL FLIRTING WITH SVR CRITERIA
AT TIMES. SITN OVER E-C WI STILL MARGINAL AT BEST. FRONTAL
BOUNDARY SHOWING UP AS FINE-LINE ON RADAR. THE SVR RISK IS OVER
FOR AREAS BEHIND THE FINE-LINE. STILL A LITTLE NERVOUS ABOUT AREAS
TO THE E...AND IT/S NOT OUT OF THE QUESTION YET THAT SOMETHING
COULD DEVELOP FARTHER E WHEN FINE-LINE STARTS TO INTERACT WITH THE LAKE
BREEZE. ADMITTEDLY...THE CHCS OF THIS KICKING OFF A SVR STORM ARE
RATHER LOW. BUT HARD TO CANCEL WATCH WITH THIS MESO-SCALE
BOUNDARY INTERACTING STILL LURKING OUT THERE. PLAN TO JUST KEEP
NIPPING AWAY AT THE WESTERN EDGE OF THE WATCH FOR NOW.

SKOWRONSKI
&&

.PREV DISCUSSION...ISSUED AT 456 PM CDT SUN MAY 20 2012...

UPDATE...SVR THREAT CONTINUES OVER NERN WI. STORMS OVER NE WI ARE
IN THE AREA OF STRONGEST MOISTURE CONVERGENCE...AND ARE LIKELY TO
POSE A RISK OF SVR UNTIL THEY EXIT THE AREA. LOCAL MESO PLOTS
SUGGEST SOME INHIBITION STILL EXISTS FM DOOR CO NWD...SO WL SEE
HOW STORMS BEHAVE AS THEY NEAR THE LAKE.

SITN OVER E-C WI LESS CLEAR CUT. STILL SOME INSTABILITY AND INCRG
MOISTURE CONVERGENCE. BUT NOT MUCH HAS HAPPENED IN THIS AREA YET.
QG FORCING SWINGING THROUGH THE AREA AND INCREASED LOW-LEVEL
CONVERGENCE SUPPORT HOLDING ONTO THE WATCH FOR A WHILE LONGER
DESPITE LIMITED DEVELOPMENT THUS FAR. SVR THREAT MAY NOT BE AS
GREAT AS IT APPEARED EARLIER...BUT NOT COMFORTABLE CANCELING THE
WATCH UNTIL FRONT GOES THROUGH AND WINDS SHIFT W.

SKOWRONSKI


DISCUSSION ISSUED AT 419 PM CDT SUN MAY 20 2012...

UPDATE...SVR THREAT ENDING BEHIND ONGOING STORMS. WL BE CLEARING
THE SWRN/FAR WRN PART OF THE FCST AREA.

ALSO ADDED SC.Y TO THE NEARSHORE WATERS. WINDS MAY NOT BE QUITE AS
GUSTY OVER THE LAKE RIGHT NOW DUE TO STABILITY CONCERNS AND SLY
FLOW UP THE LENGTH OF THE LAKE...BUT SHOULD BE QUITE STG ON THE
BAY. SHOULD SEE A BRIEF PERIOD OF G30-35 KTS WINDS RIGHT BEHIND
THE COLD FRONT...AND WLY FLOW THEN SHOULD DRIVE STRONGER GUSTS OUT
OVER THE NSH WATERS.

SKOWRONSKI


DISCUSSION ISSUED AT 238 PM CDT SUN MAY 20 2012...

SHORT TERM...TONIGHT AND MONDAY.

LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW PRESSURE
MOVING NORTHEAST OVER CENTRAL WISCONSIN EARLY THIS AFTERNOON...JUST
AHEAD OF A SHORTWAVE TROUGH OVER EASTERN MINNESOTA.  LINES OF
CONVECTION DEVELOPED AHEAD OF THIS SHORTWAVE TROUGH OVER
NORTH-CENTRAL AND NORTHWEST WISCONSIN BY MIDDAY WHERE WIND DAMAGE
AND HALF INCH HAIL OCCURRED EARLIER.  INTENSIFICATION OF THE STORMS
REMAINS POSSIBLE THROUGH THE AFTERNOON...AS THE STORMS ENCOUNTER THE
INSTABILITY AXIS FROM WAUSHARA TO LAND O LAKES WHERE ML CAPES RANGE
FROM 1000-1500 J/KG.  CAPES MAY NOT GET AS HIGH AS PREVIOUSLY
THOUGHT...SINCE SOME DRIER AIR IS MIXING DOWN TO THE SURFACE.  DEEP
LAYER SHEAR REMAINS ABOUT 30-35 KTS...THOUGH THE VAD IS PICKING UP
ON 40KTS AT 2KFT.  DAMAGING WIND GUSTS AND LARGE HAIL WILL REMAIN
THE PRIMARY THREATS WITH THE STORMS UNTIL THE SURFACE LOW AND COLD
FRONT DEPART EARLY THIS EVENING.

TONIGHT...LOW PRESSURE WILL MOVE NORTHEAST TONIGHT FROM FAR
NORTHEAST WISCONSIN TO EASTERN LAKE SUPERIOR.  THE FRONT WILL STILL
HAVE TO CLEAR DOOR COUNTY AND WILL LEAVE LIKELY POPS FOR THE FIRST
PART OF THE EVENING.  BEHIND THE FRONT...THINK WILL SEE SCATTERED
SHOWERS AND ISOLD THUNDERSTORMS EARLY THIS EVENING...THEN LIGHT
SHOWERS THROUGH MIDNIGHT AS COLDER AIR ARRIVES BEHIND THE
FRONT...AND A WIDESPREAD LOW STRATUS DECK SPREADS ACROSS THE AREA.
NORTHERN WISCONSIN MAY SEE THE LIGHT SHOWER ACTIVITY CONTINUE INTO
THE EARLY OVERNIGHT HOURS AS SOUNDINGS STILL LOOK SATURATED UP TO
ABOUT 700MB AT 06Z...BUT WILL GO DRY TO LINE UP WITH SURROUNDING
OFFICES.  AT LEAST PARTIAL CLEARING WILL ARRIVE INTO NORTH-CENTRAL
WISCONSIN LATE TONIGHT WHEN DRIER AIR MOVES INTO THAT REGION.  LOW
TEMPS RANGING FROM THE LOW 40S NORTH TO LOW 50S SE.

MONDAY...LOW STRATUS WILL PROBABLY HANG ON OVER EASTERN WISCONSIN TO
START THE DAY BUT SHOULD QUICKLY MOVE TO THE EAST DUE TO THE ARRIVAL
OF A MUCH DRIER AIRMASS AND REBOUNDING LOW LEVEL TEMPS.  AS SKIES
TURN MOSTLY CLEAR TO PARTLY CLOUDY EVERYWHERE BY LATE IN THE
MORNING...HIGHS WILL REACH FROM THE MIDDLE 60S NORTH TO LOW 70S
SOUTH.

LONG TERM...MONDAY NIGHT THROUGH NEXT SUNDAY. A COOL SURFACE HIGH
PRESSURE SYSTEM WITH UPPER RIDGE WILL SETTLE INTO THE AREA FOR THE
FIRST HALF OF THE WORK WEEK WITH QUIET WEATHER AND COMFORTABLE
TEMPERATURES. THE PREVIOUS FORECAST RUN LOWERED TEMPS FOR MONDAY
NIGHT TO WARRANT NON HEADLINE FROST WORDING FOR NORTHERN
WISCONSIN. LATEST RUNS INDICATE LIGHT RETURN FLOW PCPN ALREADY
NEAR THE MN/WI BORDER AT 12Z TUESDAY. CLOUDS MAY ADVANCE INTO
NROTHERN WISCONSIN OVERNIGHT IN THE WESTERLY FLOW TO LIMIT TEMPS
FALLING. THIS TREND SUGGESTS LESS OF A TREND TOWARD ANY FROST
ADVISORY AT THIS TIME SO WILL CONTINUE WITH THE GOING FORECAST.

MAIN FORECAST CHALLENGE ARRIVES LATER IN THE NEW WORK WEEK AS A
BROAD UPPER TROUGH WORKS INTO THE WESTERN STATES AND NORTHERN
PLAINS. MEDIUM RANGE MODELS RUNS IN BETTER AGREEMENT WITH
CONFINING BEST POTENTIAL OF CONVECTION WITH THE RETURN FLOW OVER
THE NORTHERN PLAINS WITH PERHAPS BRUSHING NORTHWEST THIRD OF THE
STATE WEDNESDAY THROUGH WEDNESDAY NIGHT. SHORT WAVE TROUGH WITH
FRONTAL SYSTEM IS PROGGED TO SLIDE OVER STATE SOMETIME FROM
THURSDAY INTO THURSDAY NIGHT TO WARRANT THE HIGHEST PCPN CHC
DURING THIS PERIOD.

FRIDAY INTO SUNDAY...THE REGION WILL BE ON THE NORTHERN PERIPHERY
OF BROAD UPPER RIDGE OVER THE SOUTHERN PLAINS INTO THE SOUTHEAST
STATES. HOWEVER MODELS DIVERT ON CRITICAL LOCATION OF SURFACE
BOUNDARY SEPARATING DEEPER MOISTURE TO THE SOUTH FROM CONTINUED
DRIER CANADA AIR. 00Z ECMWF MAINLY POSITIONS THIS BOUNDARY ALONG
THE WISCONSIN ILLINOIS BORDER WHILE THE GFS IS FURTHER SOUTH. THE
12Z GFS KEEPS THE PCPN SOUTH...WHILE DEVELOPING CONVECTION THIS
SUNDAY AFTERNOON WILL LIKELY PREVENT A CHANCE TO LOOK AT THE
LATEST ECMWF RUN.
&&

.AVIATION...LOW PRESSURE WILL TRACK OVER CENTRAL AND NORTHEAST
WISCONSIN THIS AFTERNOON AND INTO EARLY THIS EVENING.  AHEAD OF THE
LOW AND ALONG ITS COLD FRONT...NUMEROUS SHOWERS AND THUNDERSTORMS
WILL DEVELOP EARLY THIS AFTERNOON AND MOVE EAST ACROSS THE AREA
BEFORE EXITING EARLY THIS EVENING.  SOME STORMS MAY BECOME SEVERE
WITH DAMAGING WINDS AND LARGE HAIL AS THE PRIMARY THREATS.  BEHIND
THE LOW AND FRONT...A WIDESPREAD AREA OF IFR/MVFR STRATUS WILL MOVE
ACROSS THE AREA THROUGH LATE TONIGHT.  SCATTERED SHOWERS OR DRIZZLE
WILL BE POSSIBLE OUT OF THIS STRATUS DECK...MAINLY OVER N-C
WISCONSIN.  SKY CONDITIONS IMPROVE TOMORROW MORNING TO VFR.

MPC
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$








AREA FORECAST DISCUSSION...UPDATED

NWS GREEN BAY WI

 456 PM CDT SUN MAY 20 2012

.UPDATE...SVR THREAT CONTINUES OVER NERN WI. STORMS OVER NE WI ARE
IN THE AREA OF STRONGEST MOISTURE CONVERGENCE...AND ARE LIKELY TO
POSE A RISK OF SVR UNTIL THEY EXIT THE AREA. LOCAL MESO PLOTS
SUGGEST SOME INHIBITION STILL EXISTS FM DOOR CO NWD...SO WL SEE
HOW STORMS BEHAVE AS THEY NEAR THE LAKE.

SITN OVER E-C WI LESS CLEAR CUT. STILL SOME INSTABILITY AND INCRG
MOISTURE CONVERGENCE. BUT NOT MUCH HAS HAPPENED IN THIS AREA YET.
QG FORCING SWINGING THROUGH THE AREA AND INCREASED LOW-LEVEL
CONVERGENCE SUPPORT HOLDING ONTO THE WATCH FOR A WHILE LONGER
DESPITE LIMITED DEVELOPMENT THUS FAR. SVR THREAT MAY NOT BE AS
GREAT AS IT APPEARED EARLIER...BUT NOT COMFORTABLE CANCELING THE
WATCH UNTIL FRONT GOES THROUGH AND WINDS SHIFT W.

SKOWRONSKI
&&

.PREV DISCUSSION...ISSUED AT 419 PM CDT SUN MAY 20 2012...

UPDATE...SVR THREAT ENDING BEHIND ONGOING STORMS. WL BE CLEARING
THE SWRN/FAR WRN PART OF THE FCST AREA.

ALSO ADDED SC.Y TO THE NEARSHORE WATERS. WINDS MAY NOT BE QUITE AS
GUSTY OVER THE LAKE RIGHT NOW DUE TO STABILITY CONCERNS AND SLY
FLOW UP THE LENGTH OF THE LAKE...BUT SHOULD BE QUITE STG ON THE
BAY. SHOULD SEE A BRIEF PERIOD OF G30-35 KTS WINDS RIGHT BEHIND
THE COLD FRONT...AND WLY FLOW THEN SHOULD DRIVE STRONGER GUSTS OUT
OVER THE NSH WATERS.

SKOWRONSKI


DISCUSSION ISSUED AT 238 PM CDT SUN MAY 20 2012...

SHORT TERM...TONIGHT AND MONDAY.

LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW PRESSURE
MOVING NORTHEAST OVER CENTRAL WISCONSIN EARLY THIS AFTERNOON...JUST
AHEAD OF A SHORTWAVE TROUGH OVER EASTERN MINNESOTA.  LINES OF
CONVECTION DEVELOPED AHEAD OF THIS SHORTWAVE TROUGH OVER
NORTH-CENTRAL AND NORTHWEST WISCONSIN BY MIDDAY WHERE WIND DAMAGE
AND HALF INCH HAIL OCCURRED EARLIER.  INTENSIFICATION OF THE STORMS
REMAINS POSSIBLE THROUGH THE AFTERNOON...AS THE STORMS ENCOUNTER THE
INSTABILITY AXIS FROM WAUSHARA TO LAND O LAKES WHERE ML CAPES RANGE
FROM 1000-1500 J/KG.  CAPES MAY NOT GET AS HIGH AS PREVIOUSLY
THOUGHT...SINCE SOME DRIER AIR IS MIXING DOWN TO THE SURFACE.  DEEP
LAYER SHEAR REMAINS ABOUT 30-35 KTS...THOUGH THE VAD IS PICKING UP
ON 40KTS AT 2KFT.  DAMAGING WIND GUSTS AND LARGE HAIL WILL REMAIN
THE PRIMARY THREATS WITH THE STORMS UNTIL THE SURFACE LOW AND COLD
FRONT DEPART EARLY THIS EVENING.

TONIGHT...LOW PRESSURE WILL MOVE NORTHEAST TONIGHT FROM FAR
NORTHEAST WISCONSIN TO EASTERN LAKE SUPERIOR.  THE FRONT WILL STILL
HAVE TO CLEAR DOOR COUNTY AND WILL LEAVE LIKELY POPS FOR THE FIRST
PART OF THE EVENING.  BEHIND THE FRONT...THINK WILL SEE SCATTERED
SHOWERS AND ISOLD THUNDERSTORMS EARLY THIS EVENING...THEN LIGHT
SHOWERS THROUGH MIDNIGHT AS COLDER AIR ARRIVES BEHIND THE
FRONT...AND A WIDESPREAD LOW STRATUS DECK SPREADS ACROSS THE AREA.
NORTHERN WISCONSIN MAY SEE THE LIGHT SHOWER ACTIVITY CONTINUE INTO
THE EARLY OVERNIGHT HOURS AS SOUNDINGS STILL LOOK SATURATED UP TO
ABOUT 700MB AT 06Z...BUT WILL GO DRY TO LINE UP WITH SURROUNDING
OFFICES.  AT LEAST PARTIAL CLEARING WILL ARRIVE INTO NORTH-CENTRAL
WISCONSIN LATE TONIGHT WHEN DRIER AIR MOVES INTO THAT REGION.  LOW
TEMPS RANGING FROM THE LOW 40S NORTH TO LOW 50S SE.

MONDAY...LOW STRATUS WILL PROBABLY HANG ON OVER EASTERN WISCONSIN TO
START THE DAY BUT SHOULD QUICKLY MOVE TO THE EAST DUE TO THE ARRIVAL
OF A MUCH DRIER AIRMASS AND REBOUNDING LOW LEVEL TEMPS.  AS SKIES
TURN MOSTLY CLEAR TO PARTLY CLOUDY EVERYWHERE BY LATE IN THE
MORNING...HIGHS WILL REACH FROM THE MIDDLE 60S NORTH TO LOW 70S
SOUTH.

LONG TERM...MONDAY NIGHT THROUGH NEXT SUNDAY. A COOL SURFACE HIGH
PRESSURE SYSTEM WITH UPPER RIDGE WILL SETTLE INTO THE AREA FOR THE
FIRST HALF OF THE WORK WEEK WITH QUIET WEATHER AND COMFORTABLE
TEMPERATURES. THE PREVIOUS FORECAST RUN LOWERED TEMPS FOR MONDAY
NIGHT TO WARRANT NON HEADLINE FROST WORDING FOR NORTHERN
WISCONSIN. LATEST RUNS INDICATE LIGHT RETURN FLOW PCPN ALREADY
NEAR THE MN/WI BORDER AT 12Z TUESDAY. CLOUDS MAY ADVANCE INTO
NROTHERN WISCONSIN OVERNIGHT IN THE WESTERLY FLOW TO LIMIT TEMPS
FALLING. THIS TREND SUGGESTS LESS OF A TREND TOWARD ANY FROST
ADVISORY AT THIS TIME SO WILL CONTINUE WITH THE GOING FORECAST.

MAIN FORECAST CHALLENGE ARRIVES LATER IN THE NEW WORK WEEK AS A
BROAD UPPER TROUGH WORKS INTO THE WESTERN STATES AND NORTHERN
PLAINS. MEDIUM RANGE MODELS RUNS IN BETTER AGREEMENT WITH
CONFINING BEST POTENTIAL OF CONVECTION WITH THE RETURN FLOW OVER
THE NORTHERN PLAINS WITH PERHAPS BRUSHING NORTHWEST THIRD OF THE
STATE WEDNESDAY THROUGH WEDNESDAY NIGHT. SHORT WAVE TROUGH WITH
FRONTAL SYSTEM IS PROGGED TO SLIDE OVER STATE SOMETIME FROM
THURSDAY INTO THURSDAY NIGHT TO WARRANT THE HIGHEST PCPN CHC
DURING THIS PERIOD.

FRIDAY INTO SUNDAY...THE REGION WILL BE ON THE NORTHERN PERIPHERY
OF BROAD UPPER RIDGE OVER THE SOUTHERN PLAINS INTO THE SOUTHEAST
STATES. HOWEVER MODELS DIVERT ON CRITICAL LOCATION OF SURFACE
BOUNDARY SEPARATING DEEPER MOISTURE TO THE SOUTH FROM CONTINUED
DRIER CANADA AIR. 00Z ECMWF MAINLY POSITIONS THIS BOUNDARY ALONG
THE WISCONSIN ILLINOIS BORDER WHILE THE GFS IS FURTHER SOUTH. THE
12Z GFS KEEPS THE PCPN SOUTH...WHILE DEVELOPING CONVECTION THIS
SUNDAY AFTERNOON WILL LIKELY PREVENT A CHANCE TO LOOK AT THE
LATEST ECMWF RUN.
&&

.AVIATION...LOW PRESSURE WILL TRACK OVER CENTRAL AND NORTHEAST
WISCONSIN THIS AFTERNOON AND INTO EARLY THIS EVENING.  AHEAD OF THE
LOW AND ALONG ITS COLD FRONT...NUMEROUS SHOWERS AND THUNDERSTORMS
WILL DEVELOP EARLY THIS AFTERNOON AND MOVE EAST ACROSS THE AREA
BEFORE EXITING EARLY THIS EVENING.  SOME STORMS MAY BECOME SEVERE
WITH DAMAGING WINDS AND LARGE HAIL AS THE PRIMARY THREATS.  BEHIND
THE LOW AND FRONT...A WIDESPREAD AREA OF IFR/MVFR STRATUS WILL MOVE
ACROSS THE AREA THROUGH LATE TONIGHT.  SCATTERED SHOWERS OR DRIZZLE
WILL BE POSSIBLE OUT OF THIS STRATUS DECK...MAINLY OVER N-C
WISCONSIN.  SKY CONDITIONS IMPROVE TOMORROW MORNING TO VFR.

MPC
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$








AREA FORECAST DISCUSSION...UPDATED

NWS GREEN BAY WI

 419 PM CDT SUN MAY 20 2012

.UPDATE...SVR THREAT ENDING BEHIND ONGOING STORMS. WL BE CLEARING
THE SWRN/FAR WRN PART OF THE FCST AREA.

ALSO ADDED SC.Y TO THE NEARSHORE WATERS. WINDS MAY NOT BE QUITE AS
GUSTY OVER THE LAKE RIGHT NOW DUE TO STABILITY CONCERNS AND SLY
FLOW UP THE LENGTH OF THE LAKE...BUT SHOULD BE QUITE STG ON THE
BAY. SHOULD SEE A BRIEF PERIOD OF G30-35 KTS WINDS RIGHT BEHIND
THE COLD FRONT...AND WLY FLOW THEN SHOULD DRIVE STRONGER GUSTS OUT
OVER THE NSH WATERS.

SKOWRONSKI
&&

.PREV DISCUSSION...ISSUED AT 238 PM CDT SUN MAY 20 2012...

SHORT TERM...TONIGHT AND MONDAY.

LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW PRESSURE
MOVING NORTHEAST OVER CENTRAL WISCONSIN EARLY THIS AFTERNOON...JUST
AHEAD OF A SHORTWAVE TROUGH OVER EASTERN MINNESOTA.  LINES OF
CONVECTION DEVELOPED AHEAD OF THIS SHORTWAVE TROUGH OVER
NORTH-CENTRAL AND NORTHWEST WISCONSIN BY MIDDAY WHERE WIND DAMAGE
AND HALF INCH HAIL OCCURRED EARLIER.  INTENSIFICATION OF THE STORMS
REMAINS POSSIBLE THROUGH THE AFTERNOON...AS THE STORMS ENCOUNTER THE
INSTABILITY AXIS FROM WAUSHARA TO LAND O LAKES WHERE ML CAPES RANGE
FROM 1000-1500 J/KG.  CAPES MAY NOT GET AS HIGH AS PREVIOUSLY
THOUGHT...SINCE SOME DRIER AIR IS MIXING DOWN TO THE SURFACE.  DEEP
LAYER SHEAR REMAINS ABOUT 30-35 KTS...THOUGH THE VAD IS PICKING UP
ON 40KTS AT 2KFT.  DAMAGING WIND GUSTS AND LARGE HAIL WILL REMAIN
THE PRIMARY THREATS WITH THE STORMS UNTIL THE SURFACE LOW AND COLD
FRONT DEPART EARLY THIS EVENING.

TONIGHT...LOW PRESSURE WILL MOVE NORTHEAST TONIGHT FROM FAR
NORTHEAST WISCONSIN TO EASTERN LAKE SUPERIOR.  THE FRONT WILL STILL
HAVE TO CLEAR DOOR COUNTY AND WILL LEAVE LIKELY POPS FOR THE FIRST
PART OF THE EVENING.  BEHIND THE FRONT...THINK WILL SEE SCATTERED
SHOWERS AND ISOLD THUNDERSTORMS EARLY THIS EVENING...THEN LIGHT
SHOWERS THROUGH MIDNIGHT AS COLDER AIR ARRIVES BEHIND THE
FRONT...AND A WIDESPREAD LOW STRATUS DECK SPREADS ACROSS THE AREA.
NORTHERN WISCONSIN MAY SEE THE LIGHT SHOWER ACTIVITY CONTINUE INTO
THE EARLY OVERNIGHT HOURS AS SOUNDINGS STILL LOOK SATURATED UP TO
ABOUT 700MB AT 06Z...BUT WILL GO DRY TO LINE UP WITH SURROUNDING
OFFICES.  AT LEAST PARTIAL CLEARING WILL ARRIVE INTO NORTH-CENTRAL
WISCONSIN LATE TONIGHT WHEN DRIER AIR MOVES INTO THAT REGION.  LOW
TEMPS RANGING FROM THE LOW 40S NORTH TO LOW 50S SE.

MONDAY...LOW STRATUS WILL PROBABLY HANG ON OVER EASTERN WISCONSIN TO
START THE DAY BUT SHOULD QUICKLY MOVE TO THE EAST DUE TO THE ARRIVAL
OF A MUCH DRIER AIRMASS AND REBOUNDING LOW LEVEL TEMPS.  AS SKIES
TURN MOSTLY CLEAR TO PARTLY CLOUDY EVERYWHERE BY LATE IN THE
MORNING...HIGHS WILL REACH FROM THE MIDDLE 60S NORTH TO LOW 70S
SOUTH.

LONG TERM...MONDAY NIGHT THROUGH NEXT SUNDAY. A COOL SURFACE HIGH
PRESSURE SYSTEM WITH UPPER RIDGE WILL SETTLE INTO THE AREA FOR THE
FIRST HALF OF THE WORK WEEK WITH QUIET WEATHER AND COMFORTABLE
TEMPERATURES. THE PREVIOUS FORECAST RUN LOWERED TEMPS FOR MONDAY
NIGHT TO WARRANT NON HEADLINE FROST WORDING FOR NORTHERN
WISCONSIN. LATEST RUNS INDICATE LIGHT RETURN FLOW PCPN ALREADY
NEAR THE MN/WI BORDER AT 12Z TUESDAY. CLOUDS MAY ADVANCE INTO
NROTHERN WISCONSIN OVERNIGHT IN THE WESTERLY FLOW TO LIMIT TEMPS
FALLING. THIS TREND SUGGESTS LESS OF A TREND TOWARD ANY FROST
ADVISORY AT THIS TIME SO WILL CONTINUE WITH THE GOING FORECAST.

MAIN FORECAST CHALLENGE ARRIVES LATER IN THE NEW WORK WEEK AS A
BROAD UPPER TROUGH WORKS INTO THE WESTERN STATES AND NORTHERN
PLAINS. MEDIUM RANGE MODELS RUNS IN BETTER AGREEMENT WITH
CONFINING BEST POTENTIAL OF CONVECTION WITH THE RETURN FLOW OVER
THE NORTHERN PLAINS WITH PERHAPS BRUSHING NORTHWEST THIRD OF THE
STATE WEDNESDAY THROUGH WEDNESDAY NIGHT. SHORT WAVE TROUGH WITH
FRONTAL SYSTEM IS PROGGED TO SLIDE OVER STATE SOMETIME FROM
THURSDAY INTO THURSDAY NIGHT TO WARRANT THE HIGHEST PCPN CHC
DURING THIS PERIOD.

FRIDAY INTO SUNDAY...THE REGION WILL BE ON THE NORTHERN PERIPHERY
OF BROAD UPPER RIDGE OVER THE SOUTHERN PLAINS INTO THE SOUTHEAST
STATES. HOWEVER MODELS DIVERT ON CRITICAL LOCATION OF SURFACE
BOUNDARY SEPARATING DEEPER MOISTURE TO THE SOUTH FROM CONTINUED
DRIER CANADA AIR. 00Z ECMWF MAINLY POSITIONS THIS BOUNDARY ALONG
THE WISCONSIN ILLINOIS BORDER WHILE THE GFS IS FURTHER SOUTH. THE
12Z GFS KEEPS THE PCPN SOUTH...WHILE DEVELOPING CONVECTION THIS
SUNDAY AFTERNOON WILL LIKELY PREVENT A CHANCE TO LOOK AT THE
LATEST ECMWF RUN.
&&

.AVIATION...LOW PRESSURE WILL TRACK OVER CENTRAL AND NORTHEAST
WISCONSIN THIS AFTERNOON AND INTO EARLY THIS EVENING.  AHEAD OF THE
LOW AND ALONG ITS COLD FRONT...NUMEROUS SHOWERS AND THUNDERSTORMS
WILL DEVELOP EARLY THIS AFTERNOON AND MOVE EAST ACROSS THE AREA
BEFORE EXITING EARLY THIS EVENING.  SOME STORMS MAY BECOME SEVERE
WITH DAMAGING WINDS AND LARGE HAIL AS THE PRIMARY THREATS.  BEHIND
THE LOW AND FRONT...A WIDESPREAD AREA OF IFR/MVFR STRATUS WILL MOVE
ACROSS THE AREA THROUGH LATE TONIGHT.  SCATTERED SHOWERS OR DRIZZLE
WILL BE POSSIBLE OUT OF THIS STRATUS DECK...MAINLY OVER N-C
WISCONSIN.  SKY CONDITIONS IMPROVE TOMORROW MORNING TO VFR.

MPC
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$








AREA FORECAST DISCUSSION...UPDATED

NWS MILWAUKEE/SULLIVAN WI

 358 PM CDT SUN MAY 20 2012

...THIS AFTERNOON INTO EARLY EVENING...FORECAST CONFIDENCE MEDIUM.

SURFACE CONVERGENCE RIGHT ALONG THE PRE-FRONTAL TROUGH LOCATED NEAR
MADISON AND JANESVILLE AT 230 PM...IDENTIFIED BY A WIND SHIFT IN THE
SURFACE OBS...WILL BE THE FOCUS FOR SOME INITIAL CONVECTION PRIOR TO
THE MAIN FRONTAL BOUNDARY LOCATED IN THE FAR WESTERN FORECAST AREA
/CWA/...WHERE THERE IS ANOTHER WIND SHIFT. A FEW QUICK-MOVING POP-UP
SHOWERS WITH ISOLATED THUNDER ARE DEVELOPING JUST AHEAD OF THE
PRE-FRONTAL TROUGH EARLY THIS AFTERNOON AS WELL. THESE ARE A RESULT
AS GENERAL INSTABILITY WITH MIXED LAYER CAPE AROUND 1000 J/KG.

STEEP LOW LEVEL LAPSE RATES WITH A WELL-MIXED LAYER UP TO 7000 FEET
ARE ALLOWING FOR WINDS GUSTING UP TO 30 KNOTS. EXPECT HIGHER GUSTS
BENEATH SHOWERS WITH VIRGA.

EXPECT MORE THUNDERSTORM DEVELOPMENT OVER THE NEXT TWO HOURS IN THE
CENTRAL CWA...ESPECIALLY BETWEEN THE PRE-FRONTAL TROUGH AND MAIN
TROUGH WHERE THERE IS A PLUME OF HIGHER CAPE VALUES PER LATEST SPC
MESOSCALE ANALYSIS. POTENTIAL FOR SEVERE STORMS IS HIGHEST AS THIS
CORRIDOR SHIFTS INTO SOUTHEAST WI BETWEEN 21Z AND 00Z THIS
AFTERNOON. VERY ISOLATED ONE-INCH HAIL AND DAMAGING WIND GUSTS TO 60
MPH WOULD BE THE SEVERE THREAT. THERE IS NOT ENOUGH 6KM BULK SHEAR
OR LOW LEVEL SHEAR TO SUPPORT WELL-ORGANIZED SUPERCELLS OR
LONG-LIVED STORMS THAT WOULD PRODUCE WIDESPREAD SEVERE STORMS.

17Z HRRR CONTINUES TO SHOW A N-S ORIENTED UNORGANIZED LINE OF
THUNDERSTORMS THAT DEVELOP EAST OF MADISON AT 20Z AND TRACK DUE EAST
TO THE SHORELINE AT 23Z. MODELS AGREE ON ALL TSTORMS OUT OF CWA BY
00Z. LEFT SMALL CHANCE POPS IN THE FAR EAST THROUGH 03Z TO ACCOUNT
FOR POSSIBLE SLOWER MOVEMENT...THEN DRY WEATHER FOR THE REST OF THE
NIGHT.

.TONIGHT AND MONDAY...FORECAST CONFIDENCE HIGH.

VISIBLE SATELLITE AND SURFACE OBSERVATIONS SHOW PLENTY OF CLOUDS
BEHIND THE COLD FRONT THIS AFTERNOON...BUT THESE MIGHT SCATTER OUT
THIS EVENING WITH THE LOSS OF DAYTIME HEATING AND THE STEEP LOW
LEVEL LAPSE RATES...IN COMBINATION WITH SUBSIDENCE BEHIND THE FRONT.
THIS MEANS THAT THERE IS AN OUTSIDE CHANCE THAT PEOPLE IN SOUTHERN
WI COULD VIEW THE PARTIAL SOLAR ECLIPSE EARLY THIS EVENING...
FILTERED THROUGH THE THINNER CLOUDS.

A SECONDARY 500MB TROUGH WILL TRACK ACROSS WI BETWEEN MIDNIGHT
TONIGHT AND NOON MONDAY. TOO DRY FOR PRECIP. A PERIOD OF LOW STRATUS
IS EXPECTED WITH THIS FEATURE IN COMBINATION WITH COLD AIR
ADVECTION...AND THEN SKIES SHOULD CLEAR FROM WEST TO EAST JUST AFTER
SUNRISE MONDAY MORNING. EXPECT DIURNAL CUMULUS CLOUDS TO DEVELOP IN
THE EARLY AFTERNOON.

WINDS WILL BE GUSTY OUT OF THE NORTH MONDAY MORNING WITH THE COLD
AIR ADVECTION AND STEEP LOW LEVEL LAPSE RATES. WINDS WILL TAPER OFF
IN THE AFTERNOON AS HIGH PRESSURE MOVES OVER WISCONSIN. A LAKE
BREEZE WILL DEVELOP WITH THE WEAKENING PRESSURE GRADIENT AND KEEP
AREAS NEAR THE LAKE IN THE LOWER 60S/POSSIBLY UPPER 50S. INLAND
TEMPS SHOULD MAKE IT UP TO AROUND 70.

.MONDAY NIGHT THROUGH WEDNESDAY...FORECAST CONFIDENCE IS HIGH.

HIGH PRESSURE MOVES OVERHEAD MONDAY NIGHT...SLIPPING SOUTHEAST OF
WISCONSIN BY EARLY TUESDAY EVENING WITH RETURN FLOW BRINGING
WARMER TEMPS TO THE AREA ON WEDNESDAY. DRY THROUGH THIS PERIOD. A
LAKE BREEZE WILL BE FELT TUESDAY AND WEDNESDAY FOR COOLER READINGS
ALONG THE LAKE MICHIGAN SHORE. DWPNTS SHOULD MIX OUT DURING THE
DAY...SETTING UP SOME DECENT COOLING POTENTIAL BOTH MONDAY NIGHT
AND TUESDAY NIGHT.

.THURSDAY THROUGH SATURDAY...FORECAST CONFIDENCE LOW TO MEDIUM.

THE ECMWF/GFS/CANADIAN NH ARE GETTING INTO BETTER AGREEMENT WITH
THE LATE WEEK/MEMORIAL DAY WEEKEND PERIOD...AND IT IS THE
ECMWF/CANADIAN THAT ARE COMING IN LINE WITH THE GFS. THERE ARE
TIMING DIFFERENCES...BUT THEY ALL EVENTUALLY BRING A FRONT THROUGH
THE AREA...PUTTING A DAMPER ON THE ONCE EXPECTED VERY WARM
WEEKEND...AT LEAST FOR THE START OF IT. WILL HAVE A SMALL CHANCE
OF SHOWERS AND STORMS REACHING THE FORECAST AREA ON THURSDAY...BASED
ON THE FASTER GFS/CANADIAN WITH THE APPROACHING TROF/FRONT. THE
ECMWF IS DRY FOR THURSDAY...THAT MAY WELL BE TRUE.

THE ASSOCIATED LOW PRESSURE SYSTEM WITH THIS SYSTEM WILL LIFT
NORTHEAST OF THE AREA...DRAGGING A COLD FRONT THROUGH SOUTHERN
WISCONSIN PROBABLY BY FRIDAY MORNING. THIS WILL PUSH THE WARM/HOT
TEMPS SOUTH OF THE BORDER...PUTTING US IN A COOLER NORTHERLY
FLOW. THE BOUNDARY REMAINS TO THE SOUTH OF WISCONSIN THROUGH
SATURDAY WITH A COOL EAST TO NORTHEAST SETTLING IN KEEPING THE
STATIONARY SFC FRONT SOUTH OF WISCONSIN FOR THE FIRST PART OF THE
WEEKEND. IN ADDITION...WITH THE BAROCLINIC ZONE IN THE VCNTY...WE
COULD SEE SOME SHOWERS AND STORMS FROM TIME TO TIME THROUGH FRIDAY
NIGHT.

THE FRONT COULD LIFT NORTH BY SUNDAY AS SOUTHERLY WINDS INCREASE
WITH LOW PRESSURE DEVELOPING WEST OF WISCONSIN. THIS WOULD BRING
THE WARM SECTOR BACK IN FOR WARMER AND DRY CONDITIONS FOR SUNDAY
AND MEMORIAL DAY.

&&

.AVIATION/00Z TAFS/...

CONVECTION AHEAD OF A COLD FRONT MOVING ACROSS WI THIS AFTERNOON.
BULK OF THUNDERSTORMS WILL BE EAST OF MADISON BETWEEN 21Z AND
23Z...EXITING FAR EASTERN WI BY 00Z. THERE IS UNCERTAINTY ABOUT
COVERAGE OF THESE THUNDERSTORMS...AS STRONGEST FORCING WILL BE NORTH
AND SOUTH OF THE TAF SITES. SHORT TERM MODELS SUGGEST AN UNORGANIZED
LINE OF MULTI-CELL THUNDERSTORMS ORIENTED NORTH-SOUTH TRACKING
STRAIGHT EAST.

WEAK SHEAR SHOULD INHIBIT STRONG AND LONG-LASTING THUNDERSTORM
DEVELOPMENT THIS AFTERNOON...HOWEVER SHORT BURSTS OF MARGINALLY
SEVERE HAIL AND DAMAGING WINDS ARE NOT OUT OF THE QUESTION WITH ANY
STRONGER STORMS.

WEST WINDS WILL DECREASE DURING THE EVENING AND BECOME NORTH BY
MONDAY MORNING. THE NORTH WINDS WILL BE GUSTY DURING THE MORNING
HOURS WITH COLD AIR ADVECTION BEHIND DEPARTING LOW PRESSURE SYSTEM.
THEN WINDS WILL DECREASE IN THE AFTERNOON AS HIGH PRESSURE SETTLES
INTO WI.

CLOUDS SHOULD SCATTER OUT FOR A PERIOD OF TIME BEHIND THE FRONT
EARLY THIS EVENING. THEN A PERIOD OF LOW STRATUS IN THE FUEL
ALTERNATE CATEGORY IS EXPECTED WITH THIS FEATURE IN COMBINATION WITH
COLD AIR ADVECTION...AND THEN SKIES SHOULD CLEAR FROM WEST TO EAST
JUST AFTER SUNRISE MONDAY MORNING. EXPECT VFR DIURNAL CUMULUS CLOUDS
TO DEVELOP IN THE EARLY AFTERNOON.

&&

.MARINE...

WINDS HAVE POTENTIAL TO FREQUENTLY GUST TO 25 KNOTS FOR A 4 TO 6
HOUR PERIOD OF TIME MONDAY MORNING IN THE WAKE OF THE DEPARTING LOW
PRESSURE SYSTEM. HIGHEST RISK OF SMALL CRAFT ADVISORY CONDITIONS
WILL BE FROM THE NORTH POINT LIGHT AND SOUTHWARD. TOO MARGINAL AT
THIS TIME TO ISSUE A HEADLINE.
&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&

$$

TONIGHT/MONDAY AND AVIATION/MARINE...MRC
MONDAY NIGHT THROUGH SUNDAY...DAVIS









AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 321 PM CDT SUN MAY 20 2012

.SHORT TERM...TONIGHT THROUGH WEDNESDAY
321 PM CDT SUN MAY 20 2012

AFTER AN ACTIVE EARLY AFTERNOON...MAIN FORECAST CONCERNS SWITCH TO
TEMPERATURES THROUGH THE ENTIRE SHORT TERM PERIOD.

CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED RIDGING BUILDING UP OVER THE WESTERN U.S....A SHORTWAVE
TROUGH OVER MINNESOTA INTO WESTERN WISCONSIN...AND UPPER RIDGING
OVER THE EASTERN GREAT LAKES. DPVA AHEAD OF THE SHORTWAVE TROUGH...
COMBINED WITH INSTABILITY AND A SURFACE COLD FRONT TO ACT AS A
TRIGGER MECHANISM...HAS LED TO THE DEVELOPMENT OF A LINE OF SHOWERS
AND THUNDERSTORMS. THIS LINE AND COLD FRONT STRETCHES ALONG I-39 IN
WISCONSIN. MLCAPE VALUES OF 1000-1500 J/KG ARE PRESENT AHEAD OF THE
COLD FRONT. OTHER SHOWERS WERE PRESENT OVER NORTHWEST WISCONSIN...IN
AN AREA OF DEFORMATION ON THE NORTHWEST SIDE OF A SURFACE LOW IN
NORTHEAST WISCONSIN. MUCH OF THE FORECAST AREA NOW LIES IN COLD
ADVECTION BEHIND THE COLD FRONT...ALONG WITH A LOT OF STRATUS STUCK
IN THE FRONTAL INVERSION AS INDICATED ON THE 12Z MPX SOUNDING AT
915MB. A LITTLE LIGHT SHOWER/DRIZZLE ACTIVITY IS OCCURRING FROM
THESE CLOUDS TOO. TEMPERATURES HAVE FALLEN INTO THE UPPER 50S ACROSS
MUCH OF SOUTHEAST MINNESOTA...ABOUT 30 DEGREES COLDER THAN THIS TIME
YESTERDAY! CLOUDS CLEAR OUT BACK OVER WESTERN MINNESOTA AND THE
DAKOTAS WHERE DRIER AIR IS PRESENT...SEEN ON THE 12Z BIS AND ABR
SOUNDINGS. 850MB TEMPS DROP OFF QUITE A BIT TOO OVER THE
DAKOTAS...AROUND 6C AT BIS AND ABR COMPARED TO 16C AT GRB AND DVN
PER 12Z SOUNDINGS.

TONIGHT AND MONDAY...HIGH PRESSURE OVER THE DAKOTAS WILL SLIDE EAST
INTO THE FORECAST AREA ON MONDAY...IN THE WAKE OF THE CURRENT
SHORTWAVE TROUGH MOVING INTO MICHIGAN. SUBSIDENCE IN THE WAKE OF THE
TROUGH COMBINED WITH DRY AIR ADVECTION WILL ALLOW THE CLOUDS TO
GRADUALLY CLEAR OUT TONIGHT. MAY STILL BE DEALING WITH SOME
DEFORMATION LIGHT SHOWERS OVER TAYLOR AND CLARK COUNTIES THIS
EVENING...BUT EXPECT THESE TO END AS WELL WITH THE EASTWARD MOVEMENT
OF THE TROUGH. THIS LEAVES TEMPERATURES THE MAIN CONCERN. LOWS THIS
MORNING UNDER THE SURFACE HIGH WERE IN THE UPPER 30S. SINCE THE
HIGH REALLY DOES NOT BUILD INTO THE AREA TONIGHT...NOT
ANTICIPATING THE LOWS TO GET QUITE THAT COOL. HOWEVER...LOW TO
MIDDLE 40S DO SEEM LIKELY. PLENTY OF SUN ON MONDAY...COMBINED WITH
850MB TEMPS AROUND 6C AT MID DAY AND DRY AIR FOR GOOD MIXING
SUPPORT HIGHS REACHING THE LOWER 70S IN MOST LOCATIONS.

MONDAY NIGHT AND TUESDAY...UPPER RIDGING THAT HAS BEEN BUILDING OVER
THE WESTERN U.S. IS FORECAST TO BUILD INTO THE FORECAST AREA ON
TUESDAY...IN RESPONSE TO SOME FAIRLY DEEP TROUGHING DROPPING DOWN
INTO THE PACIFIC NORTHWEST. ALL MODELS AGREE THAT A DEEP LOW AROUND
OR JUST BELOW 990MB FORMS IN THE DAKOTAS DOWNSTREAM OF THIS
TROUGHING. STRENGTHENING WARM ADVECTION AHEAD OF THIS LOW AND
RIDGING BUILDING IN IS LIKELY TO RESULT IN AN EXPANSIVE AREA OF
ALTOSTRATUS AND CIRROSTRATUS. GOOD AGREEMENT EXISTS THAT THESE
CLOUDS WILL SPREAD INTO THE FORECAST AREA MONDAY NIGHT...THEN SLOWLY
SHIFT OFF TO THE EAST ON TUESDAY. RAISED CLOUD COVER CONSIDERABLY
GIVEN THE GOOD MODEL AGREEMENT ON THIS MOISTURE/CLOUDS. NO
ISENTROPIC LIFT IS NOTED WHERE THE CLOUD DECK EXISTS...THEREFORE
HAVE KEPT THE FORECAST DRY. TEMPERATURES ARE DEFINITELY
TRICKY...ESPECIALLY MONDAY NIGHT OVER WISCONSIN. WITH HIGH PRESSURE
AND DRY AIR IN PLACE OVER WISCONSIN MONDAY NIGHT...COULD SEE
TEMPERATURES DROP QUICKLY. THE CLOUDS THEN MOVE IN LATE IN THE
NIGHT. HAVE ONLY DROPPED LOWS TO NEAR 40 IN THE TYPICAL COLD SPOTS
OF WISCONSIN. SHOULD THE CLOUDS BE DELAYED...SOME FROST MENTION
WOULD BE NEEDED. TEMPERATURES MAY RISE LATE IN THE NIGHT OUT IN
SOUTHEAST MINNESOTA AS THE HIGH DEPARTS. STRENGTHENING SOUTHERLY
WINDS ON TUESDAY DUE TO A TIGHTENING PRESSURE GRADIENT...INCREASING
SUNSHINE ESPECIALLY WEST OF THE MISSISSIPPI RIVER...AND 850MB TEMPS
CLIMBING TO 10-14C BY 00Z SUPPORT HIGHS IN THE LOW 70S EAST TO NEAR
80 FAR WEST.

TUESDAY NIGHT AND WEDNESDAY...TROUGHING IS PROGGED TO CONTINUE TO
DEEPEN OVER THE WESTERN U.S. DURING THIS PERIOD...WHILE A MULTITUDE
OF SHORTWAVES EJECT OUT OF THIS TROUGH TOWARDS SOUTH CENTRAL CANADA.
THESE SHORTWAVES WILL HELP TO PUSH THE LOW INTO SOUTHEAST MANITOBA
BY 00Z THURSDAY...AND DRAG ITS COLD FRONT AT LEAST TO NEAR I-35...IF
NOT SLIGHTLY FARTHER EAST AS PROGGED BY THE 20.12Z NAM. A BIG HEAT
PLUME DEVELOPS UNDER THE LOW ON TUESDAY WHICH GETS SHUNTED EAST OVER
OUR AREA ON WEDNESDAY. 850MB TEMPS CLIMB TO AT LEAST 16-18C...IF NOT
HIGHER. IF PLENTY OF SUN OCCURS ON WEDNESDAY...GIVEN A TIGHT
PRESSURE GRADIENT IN PLACE TO MAINTAIN STRONG WINDS FOR MIXING...WE
COULD PUSH 90 AGAIN. HOWEVER...UPPER LEVEL RH PROGS SUGGEST WE MAY
BE DEALING WITH A LOT OF CIRRUS...TEMPERING THE HIGHS SOME.
CERTAINLY TUESDAY NIGHT WILL BE ABOVE NORMAL GIVEN THE BREEZY
SOUTHERLY FLOW FORECAST. LEANED TOWARD THE HIGH SIDE OF GUIDANCE FOR
LOWS. REGARDING PRECIPITATION CHANCES...WE WILL HAVE TO WAIT FOR THE
FRONT TO APPROACH GIVEN THE AREA BEING IN THE WARM SECTOR. SOME
CONCERN EXISTS THAT THE FRONT MAY NOT EVEN GET HERE AS REFERENCED
EARLIER...WITH EVEN THE 20.12Z ECMWF SLOWER STILL. THEREFORE...HAVE
KEPT PRECIPITATION CHANCES MAINLY TO THE AFTERNOON...DOWN NEAR 20
PERCENT...AND FOR WESTERN PORTIONS OF SOUTHEAST MINNESOTA ONLY.

.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
321 PM CDT SUN MAY 20 2012

THE LONG TERM FORECAST CONTINUES TO REMAIN PROBLEMATIC...WITH ISSUES
ON WHEN THE FRONT FROM WEDNESDAY MOVES INTO THE FORECAST AREA...THEN
POSSIBLE SUMMER HEAT FOR THE WEEKEND.

GOOD MODEL AGREEMENT EXISTS THAT ANOTHER SHORTWAVE EJECTING OUT OF
THE WESTERN TROUGH WILL DEVELOP A SURFACE LOW IN WESTERN KANSAS
WEDNESDAY EVENING. AS THIS SHORTWAVE LIFTS NORTHEAST...SO DOES THE
LOW...CAUSING THE WEDNESDAYS COLD FRONT EASTWARD PROGRESS TO STALL.
THE 20.12Z GEM IS BY FAR THE FASTEST BRINGING THIS SYSTEM
NORTHEAST...CROSSING THE AREA BY 18Z THURSDAY. MEANWHILE...THE GFS
JUST HAS IT GETTING INTO SOUTHEAST MINNESOTA AT 18Z THURSDAY AND THE
NEW 20.12Z ECMWF STILL HAS IT BACK IN NORTHWEST IOWA. THE VARIOUS
SPEEDS HAVE A GREAT IMPACT ON BOTH TEMPERATURES AND WHEN DPVA AND
POSSIBLY FRONTAL FORCED SHOWERS AND THUNDERSTORMS MOVE THROUGH. FOR
NOW...HAVE WENT TOWARDS A CONSENSUS SOLUTION WITH A SLIGHT LEAN
TOWARDS THE SLOWER GFS/ECMWF. THE ECMWF HAS BEEN VARYING BACK AND
FORTH TOO ON THE SPEED OF THIS SYSTEM.

NEXT PROBLEM FOR THURSDAY NIGHT AND RIGHT INTO THE WEEKEND IS THE
LOW PRESSURE SYSTEMS COLD FRONT AND HOW FAR SOUTH IT ENDS UP.
THIS ALL DEPENDS ON HOW FAST/MUCH RIDGING BUILDS OVER THE
MID-MISSISSIPPI VALLEY DOWNSTREAM OF A WELL AGREED UPON DEEP TROUGH
THAT FORMS NEAR CALIFORNIA. THE NEW 20.12Z ECMWF IS STRONGER THAN
ITS PREVIOUS RUN WITH THIS RIDGING...ALLOWING THE FRONT TO ONLY
STALL IN SOUTHERN IOWA BY FRIDAY EVENING. THE 20.12Z GEM IS SIMILAR.
ON THE OTHER HAND...THE GFS REMAINS FARTHER SOUTH DROPPING INTO
SOUTHERN MISSOURI. A CONSENSUS OF THE LAST 6 ECMWF RUNS AND TRENDS
IN THE CFSV2 MODEL SUGGEST A LEAN TOWARDS THE STRONGER RIDGING WOULD
BE PRUDENT. THEREFORE...THE FORECAST FROM THURSDAY NIGHT AND BEYOND
FOLLOWS AN OVERALL MODEL CONSENSUS WITH A LEAN TOWARDS THE 20.12Z
ECMWF. NO MATTER WHAT SOLUTION IS FOLLOWED...THE FRONT WILL MOVE
BACK NORTH AS A WARM FRONT AS THE WESTERN TROUGH SLOWLY PUSHES EAST.

MUCH OF THE EXTENDED HAS 20-40 PERCENT CHANCES FOR PRECIPITATION...
DUE TO TIMING ISSUES WITH THE WEDNESDAY NIGHT/THURSDAY/THURSDAY
NIGHT SYSTEM AND THEN THE FRONTAL BOUNDARY EVENTUALLY LIFTING BACK
NORTH FOR THE WEEKEND. IT DOES APPEAR THAT THE FRONTAL BOUNDARY MAY
GET CAPPED OFF TOWARDS SATURDAY NIGHT...ESPECIALLY SOUTH OF
I-90...SO A DRIER FORECAST IS IN PLACE THERE. TEMPERATURES SHOULD
STAY ABOVE NORMAL...AND POSSIBLY IF THE ECMWF IS RIGHT TO CLIMB INTO
THE 90S FOR SUNDAY. WILL NOT GO THAT HIGH BECAUSE OF THE VARYING
MODEL DIFFERENCES THAT EXIST.

&&

.AVIATION...THROUGH 18Z MONDAY
1239 PM CDT SUN MAY 20 2012

COLD FRONT QUICKLY MOVING EAST INTO WESTERN WISCONSIN THIS
AFTERNOON. SCATTERED THUNDERSTORMS AREA DEVELOPING AHEAD OF THIS
FRONT. A FEW OF THESE THUNDERSTORMS MAY BECOME SEVERE WITH LARGE
HAIL AND DAMAGING WINDS THE MAIN THREATS MAINLY EAST OF AN
EAU CLAIRE TO LANCASTER WISCONSIN LINE. SINCE THIS FRONT WILL BE
SHORTLY PASSING THROUGH KLSE DID NOT INCLUDE THE MENTION OF
THUNDER IN THE TAF.

BEHIND THE COLD FRONT IFR/MVFR CEILINGS EXIST. THESE LOW CLOUDS
HAVE ALREADY MOVED INTO KRST AND THEY WILL BE IN KLSE SHORTLY.
THESE LOW CLOUDS WILL PERSIST THROUGH 21.00Z AT KRST AND THROUGH
21.02Z AT KLSE.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
321 PM CDT SUN MAY 20 2012

WI...NONE.
MN...NONE.
IA...NONE.

&&

$$

SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE








AREA FORECAST DISCUSSION

NWS MILWAUKEE/SULLIVAN WI

 317 PM CDT SUN MAY 20 2012

...THIS AFTERNOON INTO EARLY EVENING...FORECAST CONFIDENCE MEDIUM.

SURFACE CONVERGENCE RIGHT ALONG THE PRE-FRONTAL TROUGH LOCATED NEAR
MADISON AND JANESVILLE AT 230 PM...IDENTIFIED BY A WIND SHIFT IN THE
SURFACE OBS...WILL BE THE FOCUS FOR SOME INITIAL CONVECTION PRIOR TO
THE MAIN FRONTAL BOUNDARY LOCATED IN THE FAR WESTERN FORECAST AREA
/CWA/...WHERE THERE IS ANOTHER WIND SHIFT. A FEW QUICK-MOVING POP-UP
SHOWERS WITH ISOLATED THUNDER ARE DEVELOPING JUST AHEAD OF THE
PRE-FRONTAL TROUGH EARLY THIS AFTERNOON AS WELL. THESE ARE A RESULT
AS GENERAL INSTABILITY WITH MIXED LAYER CAPE AROUND 1000 J/KG.

STEEP LOW LEVEL LAPSE RATES WITH A WELL-MIXED LAYER UP TO 7000 FEET
ARE ALLOWING FOR WINDS GUSTING UP TO 30 KNOTS. EXPECT HIGHER GUSTS
BENEATH SHOWERS WITH VIRGA.

EXPECT MORE THUNDERSTORM DEVELOPMENT OVER THE NEXT TWO HOURS IN THE
CENTRAL CWA...ESPECIALLY BETWEEN THE PRE-FRONTAL TROUGH AND MAIN
TROUGH WHERE THERE IS A PLUME OF HIGHER CAPE VALUES PER LATEST SPC
MESOSCALE ANALYSIS. POTENTIAL FOR SEVERE STORMS IS HIGHEST AS THIS
CORRIDOR SHIFTS INTO SOUTHEAST WI BETWEEN 21Z AND 00Z THIS
AFTERNOON. VERY ISOLATED ONE-INCH HAIL AND DAMAGING WIND GUSTS TO 60
MPH WOULD BE THE SEVERE THREAT. THERE IS NOT ENOUGH 6KM BULK SHEAR
OR LOW LEVEL SHEAR TO SUPPORT WELL-ORGANIZED SUPERCELLS OR
LONG-LIVED STORMS THAT WOULD PRODUCE WIDESPREAD SEVERE STORMS.

17Z HRRR CONTINUES TO SHOW A N-S ORIENTED UNORGANIZED LINE OF
THUNDERSTORMS THAT DEVELOP EAST OF MADISON AT 20Z AND TRACK DUE EAST
TO THE SHORELINE AT 23Z. MODELS AGREE ON ALL TSTORMS OUT OF CWA BY
00Z. LEFT SMALL CHANCE POPS IN THE FAR EAST THROUGH 03Z TO ACCOUNT
FOR POSSIBLE SLOWER MOVEMENT...THEN DRY WEATHER FOR THE REST OF THE
NIGHT.

.TONIGHT AND MONDAY...WILL BE UPDATED SOON.

.MONDAY NIGHT THROUGH WEDNESDAY...FORECAST CONFIDENCE IS HIGH.

HIGH PRESSURE MOVES OVERHEAD MONDAY NIGHT...SLIPPING SOUTHEAST OF
WISCONSIN BY EARLY TUESDAY EVENING WITH RETURN FLOW BRINGING
WARMER TEMPS TO THE AREA ON WEDNESDAY. DRY THROUGH THIS PERIOD. A
LAKE BREEZE WILL BE FELT TUESDAY AND WEDNESDAY FOR COOLER READINGS
ALONG THE LAKE MICHIGAN SHORE. DWPNTS SHOULD MIX OUT DURING THE
DAY...SETTING UP SOME DECENT COOLING POTENTIAL BOTH MONDAY NIGHT
AND TUESDAY NIGHT.

.THURSDAY THROUGH SATURDAY...FORECAST CONFIDENCE LOW TO MEDIUM.

THE ECMWF/GFS/CANADIAN NH ARE GETTING INTO BETTER AGREEMENT WITH
THE LATE WEEK/MEMORIAL DAY WEEKEND PERIOD...AND IT IS THE
ECMWF/CANADIAN THAT ARE COMING IN LINE WITH THE GFS. THERE ARE
TIMING DIFFERENCES...BUT THEY ALL EVENTUALLY BRING A FRONT THROUGH
THE AREA...PUTTING A DAMPER ON THE ONCE EXPECTED VERY WARM
WEEKEND...AT LEAST FOR THE START OF IT. WILL HAVE A SMALL CHANCE
OF SHOWERS AND STORMS REACHING THE FORECAST AREA ON THURSDAY...BASED
ON THE FASTER GFS/CANADIAN WITH THE APPROACHING TROF/FRONT. THE
ECMWF IS DRY FOR THURSDAY...THAT MAY WELL BE TRUE.

THE ASSOCIATED LOW PRESSURE SYSTEM WITH THIS SYSTEM WILL LIFT
NORTHEAST OF THE AREA...DRAGGING A COLD FRONT THROUGH SOUTHERN
WISCONSIN PROBABLY BY FRIDAY MORNING. THIS WILL PUSH THE WARM/HOT
TEMPS SOUTH OF THE BORDER...PUTTING US IN A COOLER NORTHERLY
FLOW. THE BOUNDARY REMAINS TO THE SOUTH OF WISCONSIN THROUGH
SATURDAY WITH A COOL EAST TO NORTHEAST SETTLING IN KEEPING THE
STATIONARY SFC FRONT SOUTH OF WISCONSIN FOR THE FIRST PART OF THE
WEEKEND. IN ADDITION...WITH THE BAROCLINIC ZONE IN THE VCNTY...WE
COULD SEE SOME SHOWERS AND STORMS FROM TIME TO TIME THROUGH FRIDAY
NIGHT.

THE FRONT COULD LIFT NORTH BY SUNDAY AS SOUTHERLY WINDS INCREASE
WITH LOW PRESSURE DEVELOPING WEST OF WISCONSIN. THIS WOULD BRING
THE WARM SECTOR BACK IN FOR WARMER AND DRY CONDITIONS FOR SUNDAY
AND MEMORIAL DAY.

&&

.AVIATION/00Z TAFS/...COMING SOON.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&

$$

TONIGHT/MONDAY AND AVIATION/MARINE...MRC
MONDAY NIGHT THROUGH SUNDAY...DAVIS






AREA FORECAST DISCUSSION

NWS GREEN BAY WI

 238 PM CDT SUN MAY 20 2012

.SHORT TERM...TONIGHT AND MONDAY.

LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW PRESSURE
MOVING NORTHEAST OVER CENTRAL WISCONSIN EARLY THIS AFTERNOON...JUST
AHEAD OF A SHORTWAVE TROUGH OVER EASTERN MINNESOTA.  LINES OF
CONVECTION DEVELOPED AHEAD OF THIS SHORTWAVE TROUGH OVER
NORTH-CENTRAL AND NORTHWEST WISCONSIN BY MIDDAY WHERE WIND DAMAGE
AND HALF INCH HAIL OCCURRED EARLIER.  INTENSIFICATION OF THE STORMS
REMAINS POSSIBLE THROUGH THE AFTERNOON...AS THE STORMS ENCOUNTER THE
INSTABILITY AXIS FROM WAUSHARA TO LAND O LAKES WHERE ML CAPES RANGE
FROM 1000-1500 J/KG.  CAPES MAY NOT GET AS HIGH AS PREVIOUSLY
THOUGHT...SINCE SOME DRIER AIR IS MIXING DOWN TO THE SURFACE.  DEEP
LAYER SHEAR REMAINS ABOUT 30-35 KTS...THOUGH THE VAD IS PICKING UP
ON 40KTS AT 2KFT.  DAMAGING WIND GUSTS AND LARGE HAIL WILL REMAIN
THE PRIMARY THREATS WITH THE STORMS UNTIL THE SURFACE LOW AND COLD
FRONT DEPART EARLY THIS EVENING.

TONIGHT...LOW PRESSURE WILL MOVE NORTHEAST TONIGHT FROM FAR
NORTHEAST WISCONSIN TO EASTERN LAKE SUPERIOR.  THE FRONT WILL STILL
HAVE TO CLEAR DOOR COUNTY AND WILL LEAVE LIKELY POPS FOR THE FIRST
PART OF THE EVENING.  BEHIND THE FRONT...THINK WILL SEE SCATTERED
SHOWERS AND ISOLD THUNDERSTORMS EARLY THIS EVENING...THEN LIGHT
SHOWERS THROUGH MIDNIGHT AS COLDER AIR ARRIVES BEHIND THE
FRONT...AND A WIDESPREAD LOW STRATUS DECK SPREADS ACROSS THE AREA.
NORTHERN WISCONSIN MAY SEE THE LIGHT SHOWER ACTIVITY CONTINUE INTO
THE EARLY OVERNIGHT HOURS AS SOUNDINGS STILL LOOK SATURATED UP TO
ABOUT 700MB AT 06Z...BUT WILL GO DRY TO LINE UP WITH SURROUNDING
OFFICES.  AT LEAST PARTIAL CLEARING WILL ARRIVE INTO NORTH-CENTRAL
WISCONSIN LATE TONIGHT WHEN DRIER AIR MOVES INTO THAT REGION.  LOW
TEMPS RANGING FROM THE LOW 40S NORTH TO LOW 50S SE.

MONDAY...LOW STRATUS WILL PROBABLY HANG ON OVER EASTERN WISCONSIN TO
START THE DAY BUT SHOULD QUICKLY MOVE TO THE EAST DUE TO THE ARRIVAL
OF A MUCH DRIER AIRMASS AND REBOUNDING LOW LEVEL TEMPS.  AS SKIES
TURN MOSTLY CLEAR TO PARTLY CLOUDY EVERYWHERE BY LATE IN THE
MORNING...HIGHS WILL REACH FROM THE MIDDLE 60S NORTH TO LOW 70S
SOUTH.

.LONG TERM...MONDAY NIGHT THROUGH NEXT SUNDAY. A COOL SURFACE HIGH
PRESSURE SYSTEM WITH UPPER RIDGE WILL SETTLE INTO THE AREA FOR THE
FIRST HALF OF THE WORK WEEK WITH QUIET WEATHER AND COMFORTABLE
TEMPERATURES. THE PREVIOUS FORECAST RUN LOWERED TEMPS FOR MONDAY
NIGHT TO WARRANT NON HEADLINE FROST WORDING FOR NORTHERN
WISCONSIN. LATEST RUNS INDICATE LIGHT RETURN FLOW PCPN ALREADY
NEAR THE MN/WI BORDER AT 12Z TUESDAY. CLOUDS MAY ADVANCE INTO
NROTHERN WISCONSIN OVERNIGHT IN THE WESTERLY FLOW TO LIMIT TEMPS
FALLING. THIS TREND SUGGESTS LESS OF A TREND TOWARD ANY FROST
ADVISORY AT THIS TIME SO WILL CONTINUE WITH THE GOING FORECAST.

MAIN FORECAST CHALLENGE ARRIVES LATER IN THE NEW WORK WEEK AS A
BROAD UPPER TROUGH WORKS INTO THE WESTERN STATES AND NORTHERN
PLAINS. MEDIUM RANGE MODELS RUNS IN BETTER AGREEMENT WITH
CONFINING BEST POTENTIAL OF CONVECTION WITH THE RETURN FLOW OVER
THE NORTHERN PLAINS WITH PERHAPS BRUSHING NORTHWEST THIRD OF THE
STATE WEDNESDAY THROUGH WEDNESDAY NIGHT. SHORT WAVE TROUGH WITH
FRONTAL SYSTEM IS PROGGED TO SLIDE OVER STATE SOMETIME FROM
THURSDAY INTO THURSDAY NIGHT TO WARRANT THE HIGHEST PCPN CHC
DURING THIS PERIOD.

FRIDAY INTO SUNDAY...THE REGION WILL BE ON THE NORTHERN PERIPHERY
OF BROAD UPPER RIDGE OVER THE SOUTHERN PLAINS INTO THE SOUTHEAST
STATES. HOWEVER MODELS DIVERT ON CRITICAL LOCATION OF SURFACE
BOUNDARY SEPARATING DEEPER MOISTURE TO THE SOUTH FROM CONTINUED
DRIER CANADA AIR. 00Z ECMWF MAINLY POSITIONS THIS BOUNDARY ALONG
THE WISCONSIN ILLINOIS BORDER WHILE THE GFS IS FURTHER SOUTH. THE
12Z GFS KEEPS THE PCPN SOUTH...WHILE DEVELOPING CONVECTION THIS
SUNDAY AFTERNOON WILL LIKELY PREVENT A CHANCE TO LOOK AT THE
LATEST ECMWF RUN.
&&

.AVIATION...LOW PRESSURE WILL TRACK OVER CENTRAL AND NORTHEAST
WISCONSIN THIS AFTERNOON AND INTO EARLY THIS EVENING.  AHEAD OF THE
LOW AND ALONG ITS COLD FRONT...NUMEROUS SHOWERS AND THUNDERSTORMS
WILL DEVELOP EARLY THIS AFTERNOON AND MOVE EAST ACROSS THE AREA
BEFORE EXITING EARLY THIS EVENING.  SOME STORMS MAY BECOME SEVERE
WITH DAMAGING WINDS AND LARGE HAIL AS THE PRIMARY THREATS.  BEHIND
THE LOW AND FRONT...A WIDESPREAD AREA OF IFR/MVFR STRATUS WILL MOVE
ACROSS THE AREA THROUGH LATE TONIGHT.  SCATTERED SHOWERS OR DRIZZLE
WILL BE POSSIBLE OUT OF THIS STRATUS DECK...MAINLY OVER N-C
WISCONSIN.  SKY CONDITIONS IMPROVE TOMORROW MORNING TO VFR.

MPC
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$
MPC/TDH







AREA FORECAST DISCUSSION

NWS GREEN BAY WI

 221 PM CDT SUN MAY 20 2012

.SHORT TERM...TONIGHT AND MONDAY.

LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW PRESSURE
MOVING NORTHEAST OVER CENTRAL WISCONSIN EARLY THIS AFTERNOON...JUST
AHEAD OF A SHORTWAVE TROUGH OVER EASTERN MINNESOTA.  LINES OF
CONVECTION DEVELOPED AHEAD OF THIS SHORTWAVE TROUGH OVER
NORTH-CENTRAL AND NORTHWEST WISCONSIN BY MIDDAY WHERE WIND DAMAGE
AND HALF INCH HAIL OCCURRED EARLIER.  INTENSIFICATION OF THE STORMS
REMAINS POSSIBLE THROUGH THE AFTERNOON...AS THE STORMS ENCOUNTER THE
INSTABILITY AXIS FROM WAUSHARA TO LAND O LAKES WHERE ML CAPES RANGE
FROM 1000-1500 J/KG.  CAPES MAY NOT GET AS HIGH AS PREVIOUSLY
THOUGHT...SINCE SOME DRIER AIR IS MIXING DOWN TO THE SURFACE.  DEEP
LAYER SHEAR REMAINS ABOUT 30-35 KTS...THOUGH THE VAD IS PICKING UP
ON 40KTS AT 2KFT.  DAMAGING WIND GUSTS AND LARGE HAIL WILL REMAIN
THE PRIMARY THREATS WITH THE STORMS UNTIL THE SURFACE LOW AND COLD
FRONT DEPART EARLY THIS EVENING.

TONIGHT...LOW PRESSURE WILL MOVE NORTHEAST TONIGHT FROM FAR
NORTHEAST WISCONSIN TO EASTERN LAKE SUPERIOR.  THE FRONT WILL STILL
HAVE TO CLEAR DOOR COUNTY AND WILL LEAVE LIKELY POPS FOR THE FIRST
PART OF THE EVENING.  BEHIND THE FRONT...THINK WILL SEE SCATTERED
SHOWERS AND ISOLD THUNDERSTORMS EARLY THIS EVENING...THEN LIGHT
SHOWERS THROUGH MIDNIGHT AS COLDER AIR ARRIVES BEHIND THE
FRONT...AND A WIDESPREAD LOW STRATUS DECK SPREADS ACROSS THE AREA.
NORTHERN WISCONSIN MAY SEE THE LIGHT SHOWER ACTIVITY CONTINUE INTO
THE EARLY OVERNIGHT HOURS AS SOUNDINGS STILL LOOK SATURATED UP TO
ABOUT 700MB AT 06Z...BUT WILL GO DRY TO LINE UP WITH SURROUNDING
OFFICES.  AT LEAST PARTIAL CLEARING WILL ARRIVE INTO NORTH-CENTRAL
WISCONSIN LATE TONIGHT WHEN DRIER AIR MOVES INTO THAT REGION.  LOW
TEMPS RANGING FROM THE LOW 40S NORTH TO LOW 50S SE.

MONDAY...LOW STRATUS WILL PROBABLY HANG ON OVER EASTERN WISCONSIN TO
START THE DAY BUT SHOULD QUICKLY MOVE TO THE EAST DUE TO THE ARRIVAL
OF A MUCH DRIER AIRMASS AND REBOUNDING LOW LEVEL TEMPS.  AS SKIES
TURN MOSTLY CLEAR TO PARTLY CLOUDY EVERYWHERE BY LATE IN THE
MORNING...HIGHS WILL REACH FROM THE MIDDLE 60S NORTH TO LOW 70S
SOUTH.

.LONG TERM...MONDAY NIGHT THROUGH NEXT SUNDAY. A COOL SURFACE HIGH
PRESSURE SYSTEM WITH UPPER RIDGE WILL SETTLE INTO THE AREA FOR THE
FIRST HALF OF THE WORK WEEK WITH QUIET WEATHER AND COMFORTABLE
TEMPERATURES. THE PREVIOUS FORECAST RUN LOWERED TEMPS FOR MONDAY
NIGHT TO WARRANT NON HEADLINE FROST WORDING FOR NORTHERN
WISCONSIN. LATEST RUNS INDICATE LIGHT RETURN FLOW PCPN ALREADY
NEAR THE MN/WI BORDER AT 12Z TUESDAY. CLOUDS MAY ADVANCE INTO
NROTHERN WISCONSIN OVERNIGHT IN THE WESTERLY FLOW TO LIMIT TEMPS
FALLING. THIS TREND SUGGESTS LESS OF A TREND TOWARD ANY FROST
ADVISORY AT THIS TIME SO WILL CONTINUE WITH THE GOING FORECAST.

MAIN FORECAST CHALLENGE ARRIVES LATER IN THE NEW WORK WEEK AS A
BROAD UPPER TROUGH WORKS INTO THE WESTERN STATES AND NORTHERN
PLAINS. MEDIUM RANGE MODELS RUNS IN BETTER AGREEMENT WITH
CONFINING BEST POTENTIAL OF CONVECTION WITH THE RETURN FLOW OVER
THE NORTHERN PLAINS WITH PERHAPS BRUSHING NORTHWEST THIRD OF THE
STATE WEDNESDAY THROUGH WEDNESDAY NIGHT. SHORT WAVE TROUGH WITH
FRONTAL SYSTEM IS PROGGED TO SLIDE OVER STATE SOMETIME FROM
THURSDAY INTO THURSDAY NIGHT TO WARRANT THE HIGHEST PCPN CHC
DURING THIS PERIOD.

FRIDAY INTO SUNDAY...THE REGION WILL BE ON THE NORTHERN PERIPHERY
OF BROAD UPPER RIDGE OVER THE SOUTHERN PLAINS INTO THE SOUTHEAST
STATES. HOWEVER MODELS DIVERT ON CRITICAL LOCATION OF SURFACE
BOUNDARY SEPARATING DEEPER MOISTURE TO THE SOUTH FROM CONTINUED
DRIER CANADA AIR. 00Z ECMWF MAINLY POSITIONS THIS BOUNDARY ALONG
THE WISCONSIN ILLINOIS BORDER WHILE THE GFS IS FURTHER SOUTH. THE
12Z GFS KEEPS THE PCPN SOUTH...WHILE DEVELOPING CONVECTION THIS
SUNDAY AFTERNOON WILL LIKELY PREVENT A CHANCE TO LOOK AT THE
LATEST ECMWF RUN.
&&

.AVIATION...LOW PRESSURE WILL TRACK OVER CENTRAL AND NORTHEAST
WISCONSIN THIS AFTERNOON AND INTO EARLY THIS EVENING.  AHEAD OF THE
LOW AND ALONG ITS COLD FRONT...NUMEROUS SHOWERS AND THUNDERSTORMS
WILL DEVELOP EARLY THIS AFTERNOON AND MOVE EAST ACROSS THE AREA
BEFORE EXITING EARLY THIS EVENING.  SOME STORMS MAY BECOME SEVERE
WITH DAMAGING WINDS AND LARGE HAIL AS THE PRIMARY THREATS.  BEHIND
THE LOW AND FRONT...A WIDESPREAD AREA OF IFR/MVFR STRATUS WILL MOVE
ACROSS THE AREA THROUGH LATE TONIGHT.  SCATTERED SHOWERS OR DRIZZLE
WILL BE POSSIBLE OUT OF THIS STRATUS DECK...MAINLY OVER N-C
WISCONSIN.  SKY CONDITIONS IMPROVE TOMORROW MORNING TO VFR.

MPC
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$
MPC/TDH








AREA FORECAST DISCUSSION

NWS GREEN BAY WI

 1234 PM CDT SUN MAY 20 2012

UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE.

.UPDATE...LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW
SURFACE LOW PRESSURE MOVING ACROSS WESTERN WISCONSIN AND ITS
TRAILING COLD FRONT EXTENDING SOUTHWEST OVER EASTERN IOWA AND
CENTRAL MISSOURI. ELEVATED CONVECTION IS ONGOING OVER N-C
WISCONSIN IN THE DIVERGENCE REGION AHEAD OF A DECENT LOOKING
SHORTWAVE WHICH IS MOVING NORTHEAST OVER MINNESOTA. MOSTLY CLEAR
SKIES EXIST OVER MUCH OF EASTERN WISCONSIN WHERE TEMPS ARE ALREADY
IN THE LOWER 80S.

THE STORMS NEAR HAYWARD AND MEDFORD WILL PUSH ACROSS NORTH-CENTRAL
WISCONSIN LATER THIS MORNING. MEANWHILE...SURFACE LOW PRESSURE
WILL MOVE NORTHEAST...FROM ABOUT WAUSAU TO IRON MOUNTAIN THIS
AFTERNOON. FURTHER SURFACE DESTABILIZATION ALONG WITH LARGE SCALE
ASCENT VIA SHORTWAVE AND UPPER DIVERGENCE POINTS TOWARDS SURFACE
BASED CONVECTION DEVELOPING EARLY THIS AFTERNOON. BEST GUESS AT
THE MOMENT IS FROM IRON MOUNTAIN TO WAUSHARA CORRIDOR...THEN
TRANSLATING EAST THROUGH THE AFTERNOON. AN 83/61 SURFACE PARCEL
WILL YIELD ABOUT 1700 J/KG OF ML CAPE. DEEP LAYER UNI-DIRECTIONAL
SHEAR OF 25-30 KTS (UP TO 35 KTS OVER FAR NE WISCONSIN) SUPPORTS
ISOLATED TO SLIGHT RISK CHANCES OF SEVERE THUNDERSTORMS. DAMAGING
WIND GUSTS AND LARGE HAIL WILL CONTINUE TO BE THE PRIMARY THREATS.
IF SURFACE WINDS CAN REMAINED BACK OVER FAR NE WISCONSIN DUE TO A
LAKE COMPONENT...MAY ALSO SEE AN ISOLATED TORNADO THREAT DEVELOP...BUT
NOT CONFIDENT IN THIS OCCURRING. THE FRONT STILL LOOKS TO EXIT
EARLY THIS EVENING SO THINK MOST OF THE ACTION WILL OCCUR BEFORE
THAT TIME.

MPC
&&

.PREV DISCUSSION...ISSUED AT 647 AM CDT SUN MAY 20 2012...

SHORT TERM...TODAY THROUGH MONDAY...PCPN TRENDS...THE THREAT OF
SVR TSTMS AND HEAVY RAINFALL THIS AFTERNOON AND EVG...AND TEMPERATURES
ARE THE MAIN FCST CONCERNS.

A COLD FRONT WAS SITUATED FROM WSTRN LK SUP SWWD THROUGH NW WI...
SE MN AND IA. WEAK LOW PRESSURE WAS LIFTING NE ALONG THIS BOUNDARY...
WITH ONE CIRCULATION NEAR MSP AND ANOTHER IN CENTRAL IA. WV IMAGERY
SHOWED A POTENT S/W TROF MOVG THROUGH EASTERN SD/NE...AND HEADED
TOWARD THE WSTRN GREAT LKS. IN ADDITION...THE RRQ OF AN UPPER JET
WAS SITUATED OVER THE UPPER MISS VALLEY...AND WAS PROVIDING THE
FORCING FOR A LARGE AREA OF POST-FRONTAL SHOWERS AND TSTMS OVER
EASTERN SD AND MN. MOISTURE WAS POOLING NEAR THE COLD FRONT...WITH
DEW POINTS IN THE MID 50S TO LOWER 60S. 00Z SOUNDINGS SHOWED PCPN
WATER VALUES 200 PERCENT OF NORMAL OVER MN.

THE COLD FRONT WILL EDGE EAST DURING THE DAY...AS THE S/W TROF
APPROACHES FROM THE SOUTHWEST AND THE RRQ OF THE UPPER JET
POSITIONS ITSELF OVER GRB CWA DURING THE AFTERNOON. PRECIPITABLE
WATER VALUES ARE EXPECTED TO INCREASE TO 150-200 PERCENT OF
NORMAL...WITH SFC DEW POINTS INCREASING INTO THE UPPER 50S AND
LOWER 60S...AND H8 DEW POINTS AROUND 10-12 C. ALTHOUGH MID-LEVEL
CLOUDS WILL LIMIT HEATING TO SOME DEGREE...FILTERED SUNSHINE
SHOULD ALLOW TEMPS TO WARM INTO THE LOW TO MID 80S IN NE/EC WI...
BOOSTING CAPES TO 1500-2000 J/KG THIS AFTERNOON. THE COMBINATION
OF STRONG DYNAMIC FORCING...ABUNDANT MOISTURE AND MODERATE
INSTABILITY SUPPORTS WIDESPREAD SHOWER/TSTM DEVELOPMENT LATER THIS
MORNING AND AFTERNOON. LIKELY POPS ARE WARRANTED OVER THE ENTIRE
CWA...AND HAVE BOOSTED POPS TO CATEGORICAL OVER NC WI. INGREDIENTS
ARE IN PLACE FOR HEAVY RAINFALL...AND A HANDFUL OF REPORTS OF AN
INCH OR GREATER HAVE ALREADY BEEN REPORTED UPSTREAM...INCLUDING A
4+ INCH AMOUNT IN NW IA. HAVE ADDED THE MENTION OF HEAVY RAINFALL
TO THE GRIDS/ZFP. SPC ALSO HAS MUCH OF C/NE/EC WI IN A SLGT RISK
TODAY. NOT CONFIDENT ENOUGH TO MENTION THIS EXPLICITLY IN THE
FCST...DUE TO CONCERNS ABOUT CLOUD COVER...BUT WILL MENTION AT
LEAST AN ISOLD THREAT OF DAMAGING WINDS AND HAIL IN THE HAZARDOUS
WEATHER OUTLOOK. WENT WITH A NON- DIURNAL TEMPERATURE TREND IN THE
GRIDS DUE TO THE FRONTAL PASSAGE/PCPN.

WILL HAVE A DECREASING TREND IN THE PCPN THIS EVG AS THE FRONT
EXITS THE REGION...WITH PARTIAL CLEARING OCCURRING OVERNIGHT.
STAYED CLOSE TO THE PREVIOUS FCST FOR MIN TEMPS...MAINLY 40S AND
LOWER 50S.

ON MONDAY...PARTLY CLOUDY SKIES AND MIXING THROUGH 800-775 MB
SHOULD YIELD MAX TEMPS IN THE UPPER 60S AND LOWER 70S...CLOSER
TO NORMAL.

LONG TERM...MONDAY NIGHT THROUGH SATURDAY.
A QUIET PATTERN EXPECTED MONDAY NIGHT AND TUESDAY AS CANADIAN
HIGH PRESSURE DOMINATES THE WEATHER PATTERN. A COMBINATION OF CLEAR
SKIES...LIGHT WINDS AND DEW POINTS IN THE 30S MONDAY NIGHT WILL
ALLOW TEMPERATURES TO FALL CONSIDERABLY LOWER THAN PREVIOUS FORECAST.
DID LOWER THEM SEVERAL DEGREES AND ALSO MENTIONED AREAS OF FROST
ACROSS THE NORTH. TUESDAY WILL BE SUNNY AND MILD WITH HIGHS IN
THE UPPER 60S TO MIDDLE 70S. THE HIGH WILL SLIDE EAST OF THE
AREA TUESDAY NIGHT AND WEDNESDAY. SOUTHERLY FLOW WILL ALLOW FOR
WARMER TEMPERATURES TO WORK INTO THE AREA.

THE NEXT SYSTEM WILL AFFECT THE AREA FROM LATE WEDNESDAY NIGHT INTO
THURSDAY AND THURSDAY NIGHT. HAVE A HIGH CHANCE FOR SHOWERS AND
THUNDERSTORMS THURSDAY AND THURSDAY NIGHT.

MODEL DIVERGE ON THE DETAILS OF A BUILDING 500MB RIDGE FRIDAY THROUGH
THE MEMORIAL DAY WEEKEND. 00Z GFS NOW HAS THE FRONT WELL SOUTH OF
THE AREA AND TEMPERATURES WOULD BE SOMEWHAT ABOVE NORMAL DESPITE
BEING ON THE COOL SIDE OF THE BOUNDARY. THE ECMWF ON THE OTHER HAND...
HAS THE BOUNDARY LURKING ACROSS THE STATE WITH PERIODIC CHANCES
FOR SHOWERS AND THUNDERSTORMS AS COMPLEXES OF STORMS ROLL ACROSS
THE STATE. THE ECMWF WOULD BE CONSIDERABLY WARMER THAN THE GFS.
THE CANADIAN TRENDED TOWARD THE ECMWF WITH 500MB HEIGHTS...BUT
BOUNDARY WAS JUST TO THE SOUTH OF THE AREA. DID NOT MAKE MANY
CHANGES TO THE FRIDAY AND SATURDAY PERIOD FOR NOW DUE TO THE
DIFFERENCES ON HOW THE MODELS HANDLE THE UPPER LEVEL/SURFACE
FEATURES.
&&

.AVIATION...LOW PRESSURE WILL TRACK OVER CENTRAL AND NORTHEAST
WISCONSIN THIS AFTERNOON AND INTO EARLY THIS EVENING.  AHEAD OF THE
LOW AND ALONG ITS COLD FRONT...NUMEROUS SHOWERS AND THUNDERSTORMS
WILL DEVELOP EARLY THIS AFTERNOON AND MOVE EAST ACROSS THE AREA
BEFORE EXITING EARLY THIS EVENING.  SOME STORMS MAY BECOME SEVERE
WITH DAMAGING WINDS AND LARGE HAIL AS THE PRIMARY THREATS.  BEHIND
THE LOW AND FRONT...A WIDESPREAD AREA OF IFR/MVFR STRATUS WILL MOVE
ACROSS THE AREA THROUGH LATE TONIGHT.  SCATTERED SHOWERS OR DRIZZLE
WILL BE POSSIBLE OUT OF THIS STRATUS DECK...MAINLY OVER N-C
WISCONSIN.  SKY CONDITIONS IMPROVE TOMORROW MORNING TO VFR.

MPC
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$







AREA FORECAST DISCUSSION...UPDATED

NWS MILWAUKEE/SULLIVAN WI

 1206 PM CDT SUN MAY 20 2012

.UPDATE...

TEMPS WARMING QUICKLY THIS MORNING IN THE WARM SECTOR...WITH AN
APPROACHING COLD FRONT LINED UP FROM NW WI TO EASTERN IOWA. BUMPED
UP TEMPS A BIT TO ACCOUNT FOR SEVERAL MORE HOURS OF HEATING BEFORE
THE FRONT ARRIVES.

LAKE BREEZE DEVELOPED ONCE AGAIN TODAY...ALTHOUGH IT IS NOT MAKING
MUCH HEADWAY TOWARD MITCHELL OR KENOSHA AIRPORTS DUE TO THE STRONG
SOUTHWEST SYNOPTIC FLOW.

AS FOR THUNDERSTORM POTENTIAL...DEVELOPMENT IS STILL LIKELY RIGHT
ALONG THE FRONT...WITH SCATTERED TO NUMEROUS COVERAGE. DEWPOINT
TEMPS AROUND 60 IN THE VICINITY OF THE FRONT SHOULD BE ENOUGH TO
SUPPORT AFTERNOON CONVECTION...HOWEVER THE DEWPOINTS ARE MIXING DOWN
INTO THE LOW TO MID 50S ALREADY. UPPER DIVERGENCE FROM THE RIGHT
ENTRANCE REGION OF THE UPPER JET OVERHEAD WILL COINCIDE WITH THE
COLD FRONT. MID LEVEL FORCING WILL BE RATHER WEAK...WITH THE
STRONGEST VORTICITY MAX MOVING ACROSS CENTRAL/NORTHERN WI THIS
AFTERNOON. ANOTHER VORT MAX WILL ROLL ACROSS MO/SOUTHERN IL...AND
SOUTHERN WI WILL BE CAUGHT IN THE WEAKER FORCING AREA.

13Z HRRR AND 12Z LOCAL WRF MODELS SHOW CONVECTION MOVING ACROSS OUR
FORECAST AREA IN A NORTH-SOUTH ORIENTED...UNORGANIZED MULTI-CELL
LINE THIS AFTERNOON...DEVELOPING JUST WEST OF MADISON AROUND 20-21Z
AND REACHING MILWAUKEE AROUND 23Z. THE HRRR MODEL COLUMN MAX
REFLECTIVITY HAS BEEN SHOWING A WEAKENING TREND THE PAST FEW
RUNS...BUT WE SHALL SEE WHAT THE NEXT COUPLE DO.

THERE WILL BE SUFFICIENT CAPE AROUND 1500 J/KG AND ALSO CAPE WITHIN
THE HAIL GROWTH REGION TO SUPPORT HAIL DEVELOPMENT WITH ANY OF THE
STRONGER THUNDERSTORMS THAT DEVELOP LATE THIS AFTERNOON. IN
ADDITION...DAMAGING WIND GUSTS ARE A POSSIBILITY WITH THE STEEP LOW
LEVEL LAPSE RATES. THE LIMITING FACTOR FOR WIDESPREAD SEVERE STORMS
IN OUR AREA WILL BE THE LACK OF WIND SHEAR. 6KM BULK SHEAR WILL BE
IN THE 20 TO 25 KNOT RANGE AT BEST...WHICH WOULD NOT SUSTAIN STRONG
SUPERCELL DEVELOPMENT OR LONG-DURATION STORMS.

THE BEST POTENTIAL FOR SEVERE THUNDERSTORMS WILL BE IN CENTRAL AND
NORTHERN WI...AND OUR FORECAST AREA WILL BE ON THE SOUTHERN
PERIPHERY OF THAT REGION. WILL NOT MAKE CHANGES TO THE FCST POPS FOR
THIS AFTERNOON AT THIS TIME.

&&

.AVIATION/18Z TAFS/...

THE LAKE BREEZE DEVELOPED THIS MORNING...BUT IS STALLED JUST EAST OF
MKE DUE TO THE STRONG SOUTHWEST SYNOPTIC FLOW. CURRENT THINKING IS
THAT THE LAKE BREEZE WILL NOT MAKE IT INLAND TO KENOSHA TO CAUSE THE
WIND SHIFT. THE LAKE BREEZE SHOULD AFFECT MILWAUKEE FOR A COUPLE OF
HOURS...THEN PUSH BACK TOWARD THE LAKE JUST AHEAD OF THE COLD FRONT.

CONVECTION EXPECTED TO DEVELOP JUST AHEAD OF A COLD FRONT MOVING
ACROSS WI THIS AFTERNOON...ARRIVING AT MSN AROUND 20-21Z AND MKE
AROUND 23Z. THERE IS UNCERTAINTY ABOUT COVERAGE OF THESE
THUNDERSTORMS...AS STRONGEST FORCING WILL BE NORTH OF THE TAF
SITES...TOWARD CENTRAL AND NORTHERN WI. SHORT TERM MODELS SUGGEST AN
UNORGANIZED LINE OF MULTI-CELL THUNDERSTORMS ORIENTED NORTH-SOUTH
TRACKING STRAIGHT EAST.

WEAK SHEAR SHOULD INHIBIT STRONG AND LONG-LASTING THUNDERSTORM
DEVELOPMENT THIS AFTERNOON...HOWEVER SHORT BURSTS OF MARGINALLY
SEVERE HAIL AND DAMAGING WINDS ARE NOT OUT OF THE QUESTION WITH ANY
STRONGER STORMS.

&&

.PREV DISCUSSION... /ISSUED 416 AM CDT SUN MAY 20 2012/

TODAY AND TONIGHT...CONFIDENCE...MEDIUM

THE SHORTWAVE TROUGH OVER ERN NE WILL LIFT NEWD TO WEST CENTRAL WI
BY 00Z AND CONTINUE NEWD AFTERWARD BUT ANOTHER WEAK SHORTWAVE
APPROACHING FROM THE NRN PLAINS WILL DROP SEWD INTO SRN WI FOR MON
AM. THE COLD FRONT OVER MN AND IA WILL PROGRESS FROM WEST TO EAST
ACROSS THE CWA FROM 21Z TO 02Z BUT CONVERGENCE AND FRONTOGENESIS IS
EXPECTED TO BE WEAK. VARIOUS MODELS HAVE BACKED OFF SOME ON QPF
PROBABLY DUE TO THE SHORTWAVE TROUGH TRACKING MORE NWD AND THE
AFOREMENTIONED WEAK SFC CONVERGENCE. SATELLITE TRENDS DO INDICATE
GOOD HEATING WILL OCCUR TODAY SO INCREASED TEMPS TO MID TO UPPER 80S
WITH EXPECTED MLCAPE VALUES APPROACHING 1500 J/KG FOR THIS AFTERNOON
WITH LITTLE TO NO CIN. ULTIMATELY WENT WITH LIKELY POPS IN THE NRN
CWA WHERE BETTER PVA WILL AID SFC CONVERGENCE AND CONVECTIVE
INITIATION WHILE GOING WITH 40-50 POPS IN THE SOUTH. SVR POTENTIAL
IS VERY MARGINAL GIVEN WEAK DEEP LAYER WIND SHEAR. THE SHORTWAVE
TROUGH FOR LATE TNT SHOULD NOT HAVE AN IMPACT WITH PCPN BUT WILL
PROBABLY AID IN STRATUS DEVELOPMENT IN THE COLD ADVECTION REGIME.

MONDAY - CONFIDENCE...MEDIUM
SURFACE BOUNDARY TO THE SOUTHEAST TO START THE DAY WITH 850 COOL AIR
ADVECTION BEGINNING. MID LEVEL DRY AIR IS PLENTIFUL. CONCERNED
THOUGH WITH 500 MILLIBAR VORT MAX STILL TO THE WEST AND TROUGH AXIS
NOT TO THE EAST UNTIL THE AFTERNOON. NAM IS THE SLOWEST AND ONLY
MODEL TO GENERATE LINGERING PRECIP. GFS 925-850 RH PROG IS
COMPROMISE WITH REGARD TO MORNING CLOUD TRENDS.

TUESDAY - CONFIDENCE...MEDIUM
MID LEVEL RIDGING BUILDS IN FROM THE WEST. A FEW WEAK RIPPLES IN THE
FLOW. SOUNDINGS LARGELY DRY AND QUITE STABLE...WITH GFS SHOWING SOME
MID LEVEL MOISTURE. SURFACE HIGH PROGGD TO GRADUALLY SHIFT EAST.

WEDNESDAY - CONFIDENCE...MEDIUM
UPPER RIDGE SHIFTS EAST AND BROAD SOUTHWEST FLOW DEVELOPS. WARMER
AIR HEADS NORTH ON SOUTHERLY SURFACE/850 FLOW. 850 TEMPS WELL INTO
THE TEENS. STILL ENOUGH EASTERLY COMPONENT IN THE SOUTHERLY FLOW TO
KEEP THE FAR EASTERN CWA COOLER. PREFER THE DRIER LOOK OF THE
ECMWF/GEM KEEPING PRECIP WELL TO OUR WEST AND NORTHWEST.

THURSDAY AND THURSDAY NIGHT - CONFIDENCE...MEDIUM
UPPER FLOW BECOMES INCREASINGLY CYCLONIC AS TROUGH AXIS DRAWS
CLOSER. SURFACE/850 FRONTS ALSO APPROACH AND INCREASE POTENTIAL FOR
SHRA/TSRA. FAIRLY DECENT AGREEMENT AMONGST THE MODELS WITH THIS
FROPA AND ASSOCIATED QPF FIELDS.

FRIDAY AND SATURDAY - CONFIDENCE...LOW
LOTS OF UNCERTAINTY IN THIS TIME FRAME AS ECMWF BUILDS HEIGHTS WITH
RIDGE RIDERS WHILE GFS HAS A FLATTER FLOW BUT KEEPS PRECIP FURTHER
SOUTH AND WEST CLOSER TO MORE SOUTHERN DISPLACED 850 BAROCLINIC
ZONE. ECMWF SUGGESTING A FEW PERIODS OF STORMS BEFORE FOCUS SHIFTS
FURTHER NORTH WITH THE BUILDING RIDGE AXIS. LARGE TEMPERATURE
SPREAD...AS BIG AS 25 DEGREES...CONTINUES BETWEEN GFS AND ECMWF FOR
SATURDAY. THE ALLBLEND POPS ARE QUITE LOW BOTH FRIDAY AND SATURDAY
AND THIS IS CONCERNING...ESPECIALLY FRIDAY. THIS MAY BE UNDERDONE
BUT WILL LEAVE AS IS FOR NOW BASED ON COLLAB.

AVIATION/12Z TAFS/...LOW LEVEL WIND SHEAR WILL CONTINUE UNTIL
13-14Z WHEN SFC WINDS INCREASE. OTHERWISE BREEZY SLY WINDS AND VFR
CONDITIONS EXPECTED AHEAD OF THE COLD FRONT TODAY. SCT TSTORMS ARE
EXPECTED ALONG THE COLD FRONT FROM MID TO LATE AFTERNOON INTO THE
EVENING. AFTER FROPA...MVFR CIGS WILL DEVELOP WITH CIGS EVENTUALLY
FALLING TO POSSIBLY 1 KFT. THIS WILL CONTINUE FOR MUCH OF THE NIGHT.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&

$$

UPDATE...MRC
TODAY/TONIGHT AND AVIATION/MARINE...GEHRING
MONDAY THROUGH SATURDAY...COLLAR






AREA FORECAST DISCUSSION

NWS GREEN BAY WI

 1006 AM CDT SUN MAY 20 2012

.UPDATE...LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW
SURFACE LOW PRESSURE MOVING ACROSS WESTERN WISCONSIN AND ITS
TRAILING COLD FRONT EXTENDING SOUTHWEST OVER EASTERN IOWA AND
CENTRAL MISSOURI. ELEVATED CONVECTION IS ONGOING OVER N-C
WISCONSIN IN THE DIVERGENCE REGION AHEAD OF A DECENT LOOKING
SHORTWAVE WHICH IS MOVING NORTHEAST OVER MINNESOTA. MOSTLY CLEAR
SKIES EXIST OVER MUCH OF EASTERN WISCONSIN WHERE TEMPS ARE ALREADY
IN THE LOWER 80S.

THE STORMS NEAR HAYWARD AND MEDFORD WILL PUSH ACROSS NORTH-CENTRAL
WISCONSIN LATER THIS MORNING. MEANWHILE...SURFACE LOW PRESSURE
WILL MOVE NORTHEAST...FROM ABOUT WAUSAU TO IRON MOUNTAIN THIS
AFTERNOON. FURTHER SURFACE DESTABILIZATION ALONG WITH LARGE SCALE
ASCENT VIA SHORTWAVE AND UPPER DIVERGENCE POINTS TOWARDS SURFACE
BASED CONVECTION DEVELOPING EARLY THIS AFTERNOON. BEST GUESS AT
THE MOMENT IS FROM IRON MOUNTAIN TO WAUSHARA CORRIDOR...THEN
TRANSLATING EAST THROUGH THE AFTERNOON. AN 83/61 SURFACE PARCEL
WILL YIELD ABOUT 1700 J/KG OF ML CAPE. DEEP LAYER UNI-DIRECTIONAL
SHEAR OF 25-30 KTS (UP TO 35 KTS OVER FAR NE WISCONSIN) SUPPORTS
ISOLATED TO SLIGHT RISK CHANCES OF SEVERE THUNDERSTORMS. DAMAGING
WIND GUSTS AND LARGE HAIL WILL CONTINUE TO BE THE PRIMARY THREATS.
IF SURFACE WINDS CAN REMAINED BACK OVER FAR NE WISCONSIN DUE TO A
LAKE COMPONENT...MAY ALSO SEE AN ISOLATED TORNADO THREAT DEVELOP...BUT
NOT CONFIDENT IN THIS OCCURRING. THE FRONT STILL LOOKS TO EXIT
EARLY THIS EVENING SO THINK MOST OF THE ACTION WILL OCCUR BEFORE
THAT TIME.

MPC
&&

.PREV DISCUSSION...ISSUED AT 647 AM CDT SUN MAY 20 2012...

SHORT TERM...TODAY THROUGH MONDAY...PCPN TRENDS...THE THREAT OF
SVR TSTMS AND HEAVY RAINFALL THIS AFTERNOON AND EVG...AND TEMPERATURES
ARE THE MAIN FCST CONCERNS.

A COLD FRONT WAS SITUATED FROM WSTRN LK SUP SWWD THROUGH NW WI...
SE MN AND IA. WEAK LOW PRESSURE WAS LIFTING NE ALONG THIS BOUNDARY...
WITH ONE CIRCULATION NEAR MSP AND ANOTHER IN CENTRAL IA. WV IMAGERY
SHOWED A POTENT S/W TROF MOVG THROUGH EASTERN SD/NE...AND HEADED
TOWARD THE WSTRN GREAT LKS. IN ADDITION...THE RRQ OF AN UPPER JET
WAS SITUATED OVER THE UPPER MISS VALLEY...AND WAS PROVIDING THE
FORCING FOR A LARGE AREA OF POST-FRONTAL SHOWERS AND TSTMS OVER
EASTERN SD AND MN. MOISTURE WAS POOLING NEAR THE COLD FRONT...WITH
DEW POINTS IN THE MID 50S TO LOWER 60S. 00Z SOUNDINGS SHOWED PCPN
WATER VALUES 200 PERCENT OF NORMAL OVER MN.

THE COLD FRONT WILL EDGE EAST DURING THE DAY...AS THE S/W TROF
APPROACHES FROM THE SOUTHWEST AND THE RRQ OF THE UPPER JET
POSITIONS ITSELF OVER GRB CWA DURING THE AFTERNOON. PRECIPITABLE
WATER VALUES ARE EXPECTED TO INCREASE TO 150-200 PERCENT OF
NORMAL...WITH SFC DEW POINTS INCREASING INTO THE UPPER 50S AND
LOWER 60S...AND H8 DEW POINTS AROUND 10-12 C. ALTHOUGH MID-LEVEL
CLOUDS WILL LIMIT HEATING TO SOME DEGREE...FILTERED SUNSHINE
SHOULD ALLOW TEMPS TO WARM INTO THE LOW TO MID 80S IN NE/EC WI...
BOOSTING CAPES TO 1500-2000 J/KG THIS AFTERNOON. THE COMBINATION
OF STRONG DYNAMIC FORCING...ABUNDANT MOISTURE AND MODERATE
INSTABILITY SUPPORTS WIDESPREAD SHOWER/TSTM DEVELOPMENT LATER THIS
MORNING AND AFTERNOON. LIKELY POPS ARE WARRANTED OVER THE ENTIRE
CWA...AND HAVE BOOSTED POPS TO CATEGORICAL OVER NC WI. INGREDIENTS
ARE IN PLACE FOR HEAVY RAINFALL...AND A HANDFUL OF REPORTS OF AN
INCH OR GREATER HAVE ALREADY BEEN REPORTED UPSTREAM...INCLUDING A
4+ INCH AMOUNT IN NW IA. HAVE ADDED THE MENTION OF HEAVY RAINFALL
TO THE GRIDS/ZFP. SPC ALSO HAS MUCH OF C/NE/EC WI IN A SLGT RISK
TODAY. NOT CONFIDENT ENOUGH TO MENTION THIS EXPLICITLY IN THE
FCST...DUE TO CONCERNS ABOUT CLOUD COVER...BUT WILL MENTION AT
LEAST AN ISOLD THREAT OF DAMAGING WINDS AND HAIL IN THE HAZARDOUS
WEATHER OUTLOOK. WENT WITH A NON- DIURNAL TEMPERATURE TREND IN THE
GRIDS DUE TO THE FRONTAL PASSAGE/PCPN.

WILL HAVE A DECREASING TREND IN THE PCPN THIS EVG AS THE FRONT
EXITS THE REGION...WITH PARTIAL CLEARING OCCURRING OVERNIGHT.
STAYED CLOSE TO THE PREVIOUS FCST FOR MIN TEMPS...MAINLY 40S AND
LOWER 50S.

ON MONDAY...PARTLY CLOUDY SKIES AND MIXING THROUGH 800-775 MB
SHOULD YIELD MAX TEMPS IN THE UPPER 60S AND LOWER 70S...CLOSER
TO NORMAL.

LONG TERM...MONDAY NIGHT THROUGH SATURDAY.
A QUIET PATTERN EXPECTED MONDAY NIGHT AND TUESDAY AS CANADIAN
HIGH PRESSURE DOMINATES THE WEATHER PATTERN. A COMBINATION OF CLEAR
SKIES...LIGHT WINDS AND DEW POINTS IN THE 30S MONDAY NIGHT WILL
ALLOW TEMPERATURES TO FALL CONSIDERABLY LOWER THAN PREVIOUS FORECAST.
DID LOWER THEM SEVERAL DEGREES AND ALSO MENTIONED AREAS OF FROST
ACROSS THE NORTH. TUESDAY WILL BE SUNNY AND MILD WITH HIGHS IN
THE UPPER 60S TO MIDDLE 70S. THE HIGH WILL SLIDE EAST OF THE
AREA TUESDAY NIGHT AND WEDNESDAY. SOUTHERLY FLOW WILL ALLOW FOR
WARMER TEMPERATURES TO WORK INTO THE AREA.

THE NEXT SYSTEM WILL AFFECT THE AREA FROM LATE WEDNESDAY NIGHT INTO
THURSDAY AND THURSDAY NIGHT. HAVE A HIGH CHANCE FOR SHOWERS AND
THUNDERSTORMS THURSDAY AND THURSDAY NIGHT.

MODEL DIVERGE ON THE DETAILS OF A BUILDING 500MB RIDGE FRIDAY THROUGH
THE MEMORIAL DAY WEEKEND. 00Z GFS NOW HAS THE FRONT WELL SOUTH OF
THE AREA AND TEMPERATURES WOULD BE SOMEWHAT ABOVE NORMAL DESPITE
BEING ON THE COOL SIDE OF THE BOUNDARY. THE ECMWF ON THE OTHER HAND...
HAS THE BOUNDARY LURKING ACROSS THE STATE WITH PERIODIC CHANCES
FOR SHOWERS AND THUNDERSTORMS AS COMPLEXES OF STORMS ROLL ACROSS
THE STATE. THE ECMWF WOULD BE CONSIDERABLY WARMER THAN THE GFS.
THE CANADIAN TRENDED TOWARD THE ECMWF WITH 500MB HEIGHTS...BUT
BOUNDARY WAS JUST TO THE SOUTH OF THE AREA. DID NOT MAKE MANY
CHANGES TO THE FRIDAY AND SATURDAY PERIOD FOR NOW DUE TO THE
DIFFERENCES ON HOW THE MODELS HANDLE THE UPPER LEVEL/SURFACE
FEATURES.
&&

.AVIATION...A COLD FRONT AND UPPER LEVEL DISTURBANCE WILL BRING
INCREASING SHOWER AND THUNDERSTORM ACTIVITY TO THE REGION TODAY.
THE BEST BET FOR TSTMS WILL BE LATE MORNING TO MID-AFTERNOON FOR
RHI/CWA/AUW...AND MID-AFTERNOON TO EARLY EVG AT GRB/ATW. MVFR/IFR
CONDITIONS ARE EXPECTED WITH THE TSTMS...ALONG WITH HEAVY RAINFALL
AND THE POTENTIAL FOR ISOLD SVR STORMS. PCPN SHOULD TAPER OFF
DURING THE EVG. IN THE WAKE OF THE COLD FRONT...MORE WIDESPREAD
MVFR/IFR CIGS ARE EXPECTED TO SPREAD ACROSS THE REGION. IN
ADDITION...SOME LLWS MAY DEVELOP AT RHI/AUW/CWA BY MID TO LATE
EVG..AS NORTH WINDS INCREASE TO AROUND 40 KTS AT ABOUT 1500 FEET
AGL.

KIECKBUSCH
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$







AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 1152 PM CDT SAT MAY 19 2012

.SHORT TERM...TONIGHT THROUGH MONDAY NIGHT
353 PM CDT SAT MAY 19 2012

AT 3 PM...A COLD FRONT EXTENDED FROM INTERNATIONAL FALLS MINNESOTA
TO SIOUX CITY IOWA. TEMPERATURES AHEAD OF THIS FRONT WERE IN THE
80S AND 90S. LA CROSSE WISCONSIN HAS REACHED 91 DEGREES. THIS WAS
THEIR FIRST 90-DEGREE TEMPERATURE OF 2012. BEHIND THIS FRONT...
TEMPERATURES WERE IN THE 50S AND 60S. WATER VAPOR AND PROFILERS
INDICATE A WEAK SHORT WAVE TROUGH MOVING THROUGH EASTERN MINNESOTA
AND WESTERN MINNESOTA. THIS SYSTEM IS PRODUCING SOME MID AND HIGH
CLOUDS. IN ADDITION...A FEW ISOLATED SHOWERS NEAR RED WING.
THE 19.18Z RAP AND 19.15Z HRRR CONTINUE TO SUGGEST THAT SCATTERED
SHOWERS AND THUNDERSTORMS WILL REMAIN MAINLY NORTHWEST OF A
PRESTON MINNESOTA TO NEILLSVILLE WISCONSIN LINE THIS EVENING.
WHILE THE 0-6KM SHEAR IS INCREASING TO GREATER THAN 40 KNOTS BY
20.06Z...THE ML SHEAR IS RAPIDLY DECREASING. AS A RESULT...THE
SEVERE WEATHER THREAT LOOKS VERY LOW. IF SOMETHING DID HAPPEN TO
OCCUR...DAMAGING WINDS WOULD BE THE MAIN THREAT. THIS IS MAINLY A
RESULT OF THE DRY AIR LOCATED BELOW THE CLOUD LAYER.

FROM LATE TONIGHT THROUGH EARLY SUNDAY AFTERNOON...THE COLD FRONT
WILL QUICKLY TRANSITION EASTWARD ACROSS THE FORECAST AREA. THIS IS
VERY SIMILAR TO SPEED THAT WAS SHOWN IN THE 18.12Z GFS. WITH THIS
TIMING...IT WILL BE MOVING THROUGH THE REGION DURING A TIME WHEN
THE ML CAPES WILL BE AT THEIR MINIMUM /GENERALLY LESS THAN 1000 J/KG/.
AS THE POSITIVELY TILTED TROUGH MOVES AWAY FROM THE AREA DURING
THE MORNING...THE BEST MOISTURE TRANSPORT AND 0-6 KM SHEAR WILL
MOVE NORTH AWAY FROM THE REGION. DUE TO THIS...THE AREAL COVERAGE
LOOKS TO BE SCATTERED AT BEST AND THE SEVERE WEATHER THREAT LOOKS
VERY SMALL. WITH A FASTER MOTION...THE AFTERNOON PRECIPITATION
CHANCES WERE LOWERED ACROSS THE AREA. IN ADDITION...A CLEARING
TREND IN THE CLOUDS WAS INTRODUCED. THIS LOOKS TO BE FAST ENOUGH
THAT MOST AREAS WILL GET AN OPPORTUNITY TO SEE THE ANNULAR ECLIPSE
ON SUNDAY EVENING. TEMPERATURES ACROSS NORTHEAST IOWA AND
SOUTHEAST MINNESOTA WILL LIKELY REMAIN STEADY THROUGHOUT THE DAY...
AND FALL DURING THE LATE MORNING AND AFTERNOON ACROSS WESTERN
WISCONSIN. THIS NON-DIURNAL TREND WAS INTRODUCED BY THE MIDNIGHT
CREW AND KEPT IN THE HOURLY TEMPERATURE GRIDS.

ON MONDAY...THE 850 MB TEMPERATURES LOOKS TO BE ABOUT 2C WARMER
THAN THE PREVIOUS MODELS. AS A RESULT...THE MAXIMUM TEMPERATURES
WERE RAISED ANYWHERE FROM 3 TO 5F.

.LONG TERM...TUESDAY THROUGH SATURDAY
353 PM CDT SAT MAY 19 2012

NEGATIVE OUTGOING LONG WAVE RADIATION ACROSS THE WESTERN
EQUATORIAL PACIFIC CONTINUES TO SHOW A RETROGRESSION TOWARD
INDONESIA. WITH SEA SURFACE TEMPERATURES IN THE EXCESS OF
26C...THIS AREA IS FAVORABLE TO SUPPORT STRONG TROPICAL FORCING.
NORMALLY WHEN THE CONVECTION IS ROBUST IN THIS AREA...A NEGATIVE
PACIFIC NORTH-AMERICAN TELECONNECTION DEVELOPS /WESTERN TROUGH AND
AN AMPLIFICATION OF AN EASTERN RIDGE/ ACROSS THE NORTH AMERICAN
CONTINENT. AT THE SAME TIME...ANOTHER AREA OF NEGATIVE OUTGOING
LONG WAVE RADIATION OVER THE EASTERN PACIFIC AND CENTRAL AMERICA
IS EXPECTED TO MOVE SLOWLY EAST ACROSS THE ATLANTIC. AS THIS
OCCURS...THE PERSISTENT TROUGH FROM THE MID-ATLANTIC SOUTH INTO
THE YUCATAN PENINSULA WILL MOVE EAST INTO THE CARIBBEAN.

OVERALL...THE 19.12Z MODELS SEEM TO HAVE A FAIRLY GOOD HANDLE ON
THIS SITUATION. THEY ARE IN GOOD AGREEMENT THAT A COLD FRONT WILL
MOVE SOUTHWARD INTO THE FORECAST AREA ON WEDNESDAY NIGHT...AND
THEN IT BECOMES STATIONARY FOR THURSDAY AND THURSDAY NIGHT. THIS
FRONT THEN MOVES NORTHWARD AS A WARM FRONT ON FRIDAY AS THE UPPER
LEVEL RIDGE BUILDS. THIS FRONT WILL BE THE FOCUS FOR SCATTERED
SHOWERS AND THUNDERSTORMS. IT WAS THE CONSENSUS THAT THE
OPERATIONAL GFS WAS TOO FAR SOUTH WITH THIS FRONT FROM FRIDAY INTO
SATURDAY NIGHT...THEREFORE...THE FORECAST WAS TRENDED MORE TOWARD
A BLEND OF THE ECMWF...GEM...AND A MAJORITY OF THE GFS SOLUTIONS.
BY DOING THIS...THE PRECIPITATION CHANCES WERE REMOVED SOUTH OF
THE INTERSTATE 90 CORRIDOR ON FRIDAY...AND ACROSS THE ENTIRE AREA
FROM FRIDAY NIGHT INTO SATURDAY NIGHT. IN ADDITION...THE
TEMPERATURES WERE RAISED FOR THIS TIME PERIOD. IF THE 19.12Z ECMWF
IS CORRECT ON SATURDAY...TEMPERATURES COULD BE WELL INTO THE MID
AND UPPER 90S.

&&

.AVIATION...THROUGH 06Z MONDAY
1152 PM CDT SAT MAY 19 2012

MAIN FORECAST CONCERN IS ON TIMING OF FRONT THROUGH THE TAF SITES
AND CONVECTION POTENTIAL. COLD FRONT NOW EXTENDING FROM NORTHWEST
WISCONSIN...SOUTHWEST INTO NORTHWEST IOWA. CONVECTION HAS BEEN
ONGOING ALL ALONG AND BEHIND IT...BUT HAS MADE VERY LITTLE
PROGRESS EASTWARD THIS EVENING. FRONT WILL MAKE SLOW PROGRESS
OVERNIGHT AND MOVE THROUGH TAF SITES BETWEEN 12Z-15Z. WITH WANING
INSTABILITIES AT THIS TIME DID ONLY MENTION -SHRA. 21.00Z NAM DOES
SHOW AN INVERTED TROUGH OVER THE AREA THIS AFTERNOON AS THE MAIN
SURFACE LOW MOVES EAST AND THUS LINGERS PRECIPITATION THROUGHOUT
MUCH OF THE DAY. INSTABILITIES ARE IN QUESTION WITH CLOUDS AND
FRONTAL POSITION...AS HIGHER INSTABILITIES WILL RESIDE EAST OF THE
TAF SITES. DID JUST KEPT MENTION OF SHOWERS GOING. PRECIPITATION
WILL END DURING THE LATE AFTERNOON/EARLY EVENING WITH SOME
DECREASE IN CLOUDS...ESPECIALLY AT KRST BEFORE 06Z.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
253 PM CDT SAT MAY 19 2012

WI...NONE.
MN...NONE.
IA...NONE.

&&

$$

SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...RABERDING








AREA FORECAST DISCUSSION

NWS TALLAHASSEE FL

 432 AM EDT Tue May 22 2012

...Strong to severe thunderstorms possible today...

.SYNOPSIS...
The 02 UTC regional surface analysis showed a typically weak late
May pressure pattern, except behind a weak cold front that stretched
from western TN to northern LA. There were also several outflow
boundaries from either earlier or ongoing storm complexes. In fact,
it`s difficult at times to distinguish the synoptic front from the
outflow boundaries. Vapor imagery and upper air data showed a broad
long wave trough over the Southeast U.S., with one vorticity max
ejecting northeastward off the Mid Atlantic Coast as another
was digging quickly southeastward over AL. Precip water values
have recovered to near climatology over much of our forecast area.
Strangely enough, isolated thunderstorms were developing
sporadically across our forecast area at 4 am, which is unusual
for this time of year. In fact, a loosely-organized complex of
thunderstorms was just northwest of the Elba and Ozark area in
Southeast AL.

&&

.SHORT TERM...
(Today through Thursday) A good portion of our forecast area is
under a "Slight Risk" (15% chance of a severe storm within 25 miles
of a point) of severe storms today, as the aforementioned upper
trough temporarily closes off over north GA later today. The cold
pool aloft will steepen our 700-500 mb lapse rates to the 6.5 to
7.5 deg C range, which is fairly substantial for our region. In
addition, a 500 mb level jet max is forecast to develop across our
area by this afternoon, increasing the 0-6 km vertical wind shear
magnitude to about 30 KT. This could help produce at least some
storm organization. Judging from the upstream reports over the
past 12 to 24 hours with this system, we can expect reports of
marginally severe hail (generally in the penny to quarter size
range) and damaging wind gusts in the 45 to 60 MPH range. It is
not clear how (or if) the loosely-organized thunderstorms just
northwest of our area will impact our forecast for the evolution
of today`s convection (either the amount or severity). None of the
CAM models or HRRR initialized this feature, so we are are "winging
it" a bit in the very near term. Our best guess is that is will weaken
considerably as it moves into the northwest portions of our
forecast area this morning. More storms will likely develop
later, especially in the afternoon. The incoming day shift can re-
evaluate this as needed.

Much drier air will quickly advect from west to east this
evening, bringing an end to the storms. GFS and NAM MOS have
almost no PoP for our region Wednesday because of this very dry
air aloft, but the Convection Allowing Models are managing to
generate scattered convective cells. We introduced a 20 percent
PoP for Wednesday afternoon in case a few updrafts survive the
hostile upper level environment. The only PoP we show for Thursday
is around Cross City and Perry, where there may be a bit more
moisture as weak disturbance moves quickly northeastward across
the FL Peninsula.

We expect temperatures to be near average during the mornings,
and a few degrees above average in the afternoons, with the
warmest day being Thursday (with highs in the lower to mid 90s
inland). The relative humidity will remain low enough during the
afternoons to prevent the uncomfortable muggy conditions we would
typically expect in a few weeks.

.LONG TERM...
(Thursday night through next Tuesday) Most of the extended period
will be dominated by a strong upper ridge building over the
eastern CONUS becoming centered across the Ohio Valley this
weekend. The axis of the surface ridge will extend east to west
from the western Atlantic through the Central Plains. As a result,
the local region will be under deep layer easterly flow. Monday
through Tuesday the upper ridge is forecast to break down as a
shortwave tracks from the northern Plains to the Great Lakes
region. Meanwhile, the surface ridge slides southward and weakens
with low level flow veering to the southeast to south. The only
relief from the anticipated above seasonal temperatures will be
scattered convection over the weekend and early next week from the
influx of moisture off the Atlantic. Max temperatures across
inland areas will be in the lower to mid 90s. Min temps will
generally be in the lower 70s.

&&

.AVIATION...
A brief period of MVFR vsby restriction at VLD is possible before
sunrise. Otherwise, VFR conditions will prevail with just brief MVFR
vsbys in afternoon and evening convection. Some of the storms may be
strong to severe. Winds will be from the southwest around 10 knots
outside of convection.

&&

.MARINE...
Winds and seas will remain at typically low May values through
Friday, except for some higher winds and seas this afternoon and
evening (and again on Wednesday) near the coast due to the sea
breeze circulation enhancement.

&&

.FIRE WEATHER...
The minimum relative humidity should be above 35 percent today
across north Florida today with scattered showers and thunderstorms
by afternoon. A drier airmass filters back into the region on
Wednesday and a Fire Weather Watch remain in place for interior
portions of north Florida. These areas could see relative humidities
less than 35 percent combined with dispersions greater than 75 and
ERCs greater than 20.

&&

.PRELIMINARY POINT TEMPS/POPS...
Tallahassee   90  64  91  65  93 /  50  30  20  10  10
Panama City   84  69  88  67  91 /  40  20  20  10  10
Dothan        90  65  93  66  94 /  60  30  20  10  10
Albany        90  64  91  65  93 /  50  30  20  10  10
Valdosta      92  63  91  64  92 /  50  40  20  10  10
Cross City    90  65  90  64  92 /  20  20  20  10  20
Apalachicola  85  67  86  68  84 /  30  10  20  10  10

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
AL...None.
GA...None.
FL...Fire Weather Watch from Wednesday afternoon through Wednesday
     evening for Calhoun-Gadsden-Holmes-Inland Jefferson-Inland
     Walton-Jackson-Lafayette-Leon-Liberty-Madison-Washington.

GM...None.

&&

$$

LONG TERM/AVIATION/FIRE WX...Barry
Rest of Discussion...Fournier






AREA FORECAST DISCUSSION

NWS GOODLAND KS

 1155 PM MDT MON MAY 21 2012

.UPDATE...
ISSUED AT 1139 PM MDT MON MAY 21 2012

WINDS HAVE STEADILY INCREASED DURING THE LAST COUPLE OF HOURS
ACROSS MOST OF THE AREA AS THE STRONG PRESSURE GRADIENT REMAINS IN
PLACE AND THE LOW LEVEL JET DEVELOPS. WINDS WILL BE STRONGEST
ALONG THE COLORADO BORDER WHERE THE WINDS FROM THE LOW LEVEL JET
WILL BE ABLE TO BETTER MAKE IT TO THE SURFACE. THE WINDS SHOULD
DECREASE SOME OVER THE WEST DURING THE OVERNIGHT HOURS AS THE LOW
LEVEL JET MOVES SLIGHTLY TO THE EAST.

OVER THE LAST FEW HOURS THE RUC HAS BACKED OFF ON FOG DEVELOPMENT
OVERNIGHT...AND THE NAM HAS BECOME EVEN DRIER THAN THE PREVIOUS
MODEL RUN. HOWEVER...WITH THE BREEZY SOUTH WINDS BRINGING HIGHER
DEW POINTS IN DURING THE NIGHT...WILL LEAVE IN THE MENTION OF
PATCHY FOG FOR ROUGHLY THE SOUTHERN HALF OF THE AREA.

UPDATED SOME OF THE FORECAST FOR TOMORROW...MAINLY FOR THE WINDS
OVER THE EASTERN PART OF THE AREA. INCREASED THE WINDS SOME BASED
OFF THE LATEST MIXED LAYER WINDS FROM THE NAM/SREF. STILL LOOKS
LIKE THE POTENTIAL IS THERE FOR CRITICAL FIRE WEATHER. HOWEVER THE
QUESTION IS IF THE WINDS AND LOW RHS WILL BE COLOCATED LONG ENOUGH
TO WARRANT A HIGHLIGHT. WILL LET THE MID SHIFT TAKE A LOOK AT THIS
AND HOLD OFF ISSUING ANY THING AT THIS TIME.

UPDATE ISSUED AT 822 PM MDT MON MAY 21 2012

INCREASED PRECIPITATION CHANCES OVER PART OF SOUTHWEST NEBRASKA AS
A THUNDERSTORM APPROACHES THE AREA. STORM SHOULD EXIT THE
SOUTHWEST NEBRASKA AND FAR NORTHWEST KANSAS AROUND MIDNIGHT ASSUMING IT
WILL AT CONTINUE AT ITS CURRENT RATE OF SPEED AND DIRECTION.


&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 121 PM MDT MON MAY 21 2012

16Z WATER VAPOR IMAGERY/RUC ANALYSIS INDICATED BROAD RIDGING IN
PLACE ACROSS THE CENTRAL ROCKIES AND ADJACENT HIGH PLAINS...WITH
TROUGH APPROACHING THE PACIFIC NORTHWEST. AT THE SFC...TROUGH WAS IN
PLACE ACROSS CENTRAL AND EASTERN COLORADO ...ROUGHLY BETWEEN KDNR
AND KAKO. TO THE EAST OF THIS TROUGH...MOISTURE ADVECTION WAS
INCREASING WITH AN AREA OF DEW POINTS AT OR ABOVE 50 F FROM KLIC
SOUTHEAST INTO THE OKLAHOMA PANHANDLE. 12Z RAOBS AT DNR AND DDC
INDICATED AREA OF STEEP MID LEVEL LAPSE RATES BETWEEN H7 AND
H6...WITH A MUCH DEEPER LAYER NOTED AT DNR.

MAIN CONCERN FOR THE SHORT TERM PERIODS WILL BE CONVECTIVE
INITIATION CHANCES TODAY AND TEMPS/RH/FIRE WX TOMORROW.

REST OF THE AFTERNOON-TONIGHT...WITH AFOREMENTIONED MOISTURE
ADVECTION ALREADY ONGOING PER SFC OBS...AND NOSE OF STEEP MID LEVEL
LAPSE RATES IN PLACE ALONG SFC TROUGH ACROSS EASTERN COLORADO
CONFIDENCE INCREASING IN CONVECTIVE INITIATION ALONG SFC TROUGH THIS
AFTERNOON...ESPECIALLY GIVEN THAT MIXED LAYER TDS ARE VERY SIMILAR
TO FORECAST SFC VALUES INDICATING SOME DEPTH TO THE MOISTURE
PROFILE. WHILE CONFIDENCE IN DEVELOPMENT OF THUNDERSTORMS IS
HIGHER...HIGHER RES MODELS KEEPING COVERAGE FAIRLY SPARSE AND WITH
LATEST HRRR JUMPING AROUND QUITE A BIT WITH TIMING AND LOCATION...DO
NOT THINK POPS ABOVE THE 20-30 PERCENT RANGE WARRANTED JUST YET.
WITH A LOT OF UNCERTAINTY IN THE DETAILS...HAVE GENERALLY WENT WITH
BROADER COVERAGE OF POPS STARTING FIRST AROUND SFC TROUGH AROUND 20Z
AND GRADUALLY SHIFTING EAST AND DIMINISHING. SOME ELEVATED
INSTABILITY REMAINS THROUGH THE NIGHT WITH SOME WEAK ASCENT EXPECTED
TO THE WEST OF H7 THERMAL RIDGE. PROBABILISTIC GUIDANCE NOT REALLY
SUPPORTING MUCH OF A PRECIP THREAT AT THIS POINT...BUT CANNOT
TOTALLY RULE OUT SOME ELEVATED OVERNIGHT STORMS AND WILL GENERALLY
KEEP PREVIOUS FORECAST IN THIS REGARD. GIVEN ALREADY OBSERVED
MOISTURE TRANSPORT...DO HAVE SOME CONCERNS ABOUT THE DEVELOPMENT OF
FOG OVERNIGHT. WINDS SHOULD GENERALLY STAY UP WHICH WILL MINIMIZE
THE THREAT SOME WHAT...BUT GIVEN EXPECTED MOISTURE PROFILE AND SREF
INDICATING A SMALL THREAT FOR FOG THINK AT LEAST A PATCHY MENTION IS
IN ORDER.

TUESDAY...H5 RIDGE AXIS WILL SHIFT TO THE EAST THROUGH THE
DAY...WITH CWA UNDER THE INFLUENCE OF LARGE SCALE FORCING FOR
SUBSIDENCE THROUGH MUCH OF THE DAY. WHILE SYNOPTIC SCALE SUPPORT IS
LACKING...FAIRLY STRONG AND PERSISTENT CONVERGENCE EXPECTED ALONG
DRY LINE THAT WILL DEVELOP ACROSS AREA DURING THE AFTERNOON. COULD
POTENTIALLY SEE A STORM OR TWO DEVELOP IN THIS AREA...BUT GIVEN
LARGE SCALE PATTERN...POTENTIAL FOR A STRONG CAP AND VERY LOW
PROBABILITIES FROM THE NORMALLY WET SREF DATABASE...CONFIDENCE NOT
HIGH ENOUGH TO INCLUDE THUNDERSTORM THREAT AT THIS TIME. MIXED LAYER
TEMPS STILL SUPPORT TEMPS IN THE 90S ACROSS MUCH OF THE
AREA...ALTHOUGH THERE DOES APPEAR TO BE SOME DISCREPANCIES FOR HOW
WARM THINGS WILL GET WITH SREF INDICATING A RANGE BETWEEN 97 AND
AROUND 88 FOR GLD. GIVEN OVERALL PATTERN AND POTENTIAL TO BE ON MUCH
DRIER SIDE OF THE DRY LINE THINK WARMER SOLUTIONS THE WAY TO AND MADE
ONLY MINOR CHANGES TO GOING FORECAST.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 236 PM MDT MON MAY 21 2012

A COLD FRONT WILL DROP SOUTH TOWARDS OUR CWA TUESDAY NIGHT AS A
SHORTWAVE TROUGH MOVES ACROSS THE NORTHERN PLAINS. WITH AIR MASS OVER
CWA GENERALLY STABILIZING TUESDAY EVENING THUNDERSTORM CHANCES
REMAIN MINIMAL AND WILL BE TIED MAINLY TO WHAT DEVELOPS DURING THE
AFTERNOON. MODEL DIFFERENCES IN THE TIMING/POSITION OF THE FRONT
WILL HAVE A LARGER IMPACT ON THE TEMPERATURE FORECAST WEDNESDAY WHEN
IT WILL STALL OVER THE CWA AND THEN LIFT NORTH AS A WARM FRONT.
ECMWF AND GFS TEND TO BE THE QUICKEST IN DEVELOPING A STRONG LEE
TROUGH OVER EASTERN COLORADO...PUSHING THE FRONT NORTH BY MIDDAY.
CURRENT HIGH TEMP FORECAST FOR WEDNESDAY REFLECTS A BLEND OF
SOLUTIONS WITH UPPER 90S OVER SW PART OF THE CWA...AND UPPER 70S IN
THE NORTHWEST. WERE THE FRONT TO LIFT QUICKER...MID-UPPER 90S COULD
BE EXPECTED ACROSS A MUCH LARGER PART OF THE CWA. WITH THE SURFACE
TROUGH EXPECTED TO BE OVER THE CWA BY MIDDAY...STRONGEST SURFACE
GRADIENT SHOULD REMAIN EAST...SO WINDS SHOULD REMAIN BELOW RED FLAG
CRITERIA.

LARGE SCALE TROUGH DEVELOPS OVER THE GREAT BASIN/NORTHERN ROCKIES BY
WEDNESDAY AFTERNOON...WITH A SERIES OF WEAK SHORTWAVE TROUGH MOVING
JUST NORTH AND WEST OF THE CWA THROUGH NEXT WEEKEND. THE FIRST
SHORTWAVE ARRIVES BY WEDNESDAY NIGHT...WITH THUNDERSTORMS POSSIBLY
INITIATING OVER NORTHEAST COLORADO. BEST CHANCES WILL BE ACROSS THE
NORTH AFTER MIDNIGHT WEDNESDAY NIGHT WHEN A COLD FRONT WILL MOVE
INTO SOUTHWEST NEBRASKA AND STALL. I HAVE LESS CONFIDENCE FURTHER
SOUTH AND EAST...HOWEVER WITH AT LEAST SOME GUIDANCE SHOWING
DEVELOPMENT TOWARDS THE I-70 CORRIDOR...I FELT COMFORTABLE KEEPING
SLIGHT CHANCE/CHANCE POPS IN PLACE.

BY THURSDAY THIS INITIAL SHORTWAVE WILL MOVE TO THE EAST WITH
SUBSIDENCE BUILDING IN OVER THE CWA IN IT WAKE. AT THE SAME TIME
ANOTHER WEAK DISTURBANCE WILL BE MOVING IN FROM THE WEST BY THURSDAY
AFTERNOON/NIGHT...WITH POPS INCREASING ONCE AGAIN FROM THE
WEST...AND CHANCES LIMITED TO NORTH OF INTERSTATE 70.

FRIDAY-MONDAY...LARGE SCALE TROUGH REMAINS IN PLACE ACROSS THE
WESTERN CONUS...EVENTUALLY BREAKING DOWN AND TRANSITIONING TO A
WESTERLY ZONAL PATTERN BY EARLY NEXT WEEK. RESULT WILL BE A FAIRLY
ACTIVE PATTERN...WITH STORM TRACK FAVORING NORTHERN PORTIONS OF OUR
CWA FOR SHOWER/THUNDERSTORM CHANCES. CONFIDENCE WAS TOO LOW TO RAISE
POPS BEYOND 20/30 RANGE...CONSIDERING DIFFERENCE IN TIMING OF THESE
FEATURES...AND DIFFERENCES IN POSITION OF SURFACE FEATURES AS
HANDLED BY GUIDANCE.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1139 PM MDT MON MAY 21 2012

VFR CONDITIONS ARE FORECAST FOR THE 6Z TAFS. WINDS WILL REMAIN
BREEZY FOR KGLD OVERNIGHT AS A FAIRLY TIGHT PRESSURE GRADIENT REMAINS
IN PLACE OVER THE AREA. MODELS HAVE BACKED OFF THE POTENTIAL FOR
FOG...BUT WITH DEW POINTS SLOWLY CLIMBING THROUGH THE EVENING
WILL CONTINUE TO KEEP THE LOW VFR VIS IN TOWARD THE EARLY MORNING
HOURS FOR KGLD. ALSO KEPT IN THE MENTION OF LOW CLOUDS AT BOTH SITES
AS SOUNDINGS AND CROSS SECTIONS BOTH SHOW THE POTENTIAL FOR CLOUDS
TO DEVELOP IN THE IFR RANGE...ALTHOUGH NOT ENOUGH TO WARRANT AN
IFR CEILING GROUP. WINDS WILL STRENGHTEN SOME DURING THE
MORNING...POTENTIALLY INCREASING FURTHER DURING THE AFTERNOON AND
INTO THE EVENING.


&&

.FIRE WEATHER...
ISSUED AT 121 PM MDT MON MAY 21 2012

VERY WARM AND DRY WEATHER IS EXPECTED ACROSS MUCH OF THE AREA ON
TUESDAY...WITH AFTERNOON HUMIDITIES BELOW 15 PERCENT EXPECTED
ALONG AND EAST OF THE COLORADO AND KANSAS STATE LINE. WESTERLY
WINDS WILL GRADUALLY INCREASE IN THIS AREA TO AROUND 15 MPH IN THE
AFTERNOON. WITH RECENT RAINFALL AND WINDS NOT EXPECTED TO INCREASE
TO LATE IN THE AFTERNOON...OVERALL CONFIDENCE IN CRITICAL FIRE
WEATHER CONDITIONS IS TOO LOW TO WARRANT A WATCH OR WARNING AT
THIS POINT.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&

$$

UPDATE...JTL
SHORT TERM...JRM
LONG TERM...DR
AVIATION...JTL
FIRE WEATHER...JRM







AREA FORECAST DISCUSSION

NWS WAKEFIELD VA

 234 AM EDT TUE MAY 22 2012

.SYNOPSIS...
LOW PRESSURE AND UNSETTLED CONDITIONS WILL PERSIST ACROSS THE AREA
THROUGH MID WEEK. HIGH PRESSURE BUILDS INTO THE AREA LATE THIS WEEK
INTO THE HOLIDAY WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
UPDATE TO ADD 30 PERCENT CHC SHOWERS/ISOLATED THUNDER MOST AREAS
WEST OF THE CHESAPEAKE. HRRR AND OTHER HIGH RES MODELS INDICATE
CONVECTION OVERNIGHT IN AN AREA THAT HAS SLIGHTLY NEGATIVE LI/S.
AS OF 03Z...SHOWERS WERE OVER BRUNSWICK COUNTY AND APPROACHING
LUNENBURG AND MECKLENBURG COUNTY FROM THE WEST. LEFT SLGT CHC
SHOWERS ERN PORTIONS WHERE THE ATMPOSPHERE IS RELATIVELY STABLE.

PREVIOUS DISCUSSION...
MOST PCPN HAS WEAKENED / DISSIPATED SINCE SUNSET WITH ONLY A FEW
SHOWERS OVER I95 CORRIDOR NORTH OF RICHMOND. NOW WATCHING BAND OF
SHOWERS / TSTRMS FROM LYH-DAN. TUFF CALL ON JUST HOW FAR EAST THEY
GET NEXT FEW HOURS AS SHORT RANGE MODELS DIFFER A BIT ON HOW LONG
THEY SURVIVE. THUS...HAVE ADDED ISLTD THUNDER TO EXTREME WESTERN
COUNTIES NEXT FEW HOURS FOR ANY CELL THAT DOES MOVE EAST. OTW...ENUF
MOISTURE IN PLACE FOR AT LESAT ISOLATED SHOWERS FOR THE REST OF THE
NIGHT...ESPECIALLY ACROSS WESTERN HALF OF FA DUE TO LINGERING TROF.
ADDED PATCHY FOG ALONG THE EASTERN SHORE. LATER UPDATES MAY HAVE TO
EXPAND THE FOG THREAT TOWARD SUNRISE. WARM AND HUMID. LOWS 60-65.

&&

.SHORT TERM /TONIGHT THROUGH THURSDAY/...
UNSETTLED CONDS...NOT DUE TO TS ALBERTO...WILL CONTINUE THRU THE
SHORT TERM PERIOD WITH THE AFOREMENTIONED UPR-LVL TROF STILL IN
PLACE ALONG THE EASTERN SEABOARD. THIS WILL LEAD TO PERIODIC
CHANCES FOR SHOWERS AND STORMS AS MOIST S/SW FLOW CONTINUES. FOR
TUE...SFC TROF WILL BE SITUATED OVR WESTERN PORTIONS OF THE FA
WHERE HIGHEST POPS (50%) WERE PLACED...30-40% ELSEWHERE. TEMPS
CLIMB INTO THE UPR 70S TO LWR 80S UNDER A MSTLY CLDY SKY. RAIN MAY
LINGER INTO TUE NGT...WITH THE BEST CHC AGAIN OVR WESTERN AREAS.
UPR-LVL TROF CUTS OFF FROM THE MEAN FLOW TUE NGT INTO WED AS A
POTENT S/W DIVES DOWN THE TROF BASE. THE CENTER OF THE RESULTING
UPR-LVL LOW WILL CENTER ITSELF NEAR THE MID ATLANTIC WED INTO
THU...WITH CHANCES FOR RAIN EACH DAY. BEST CHANCE FOR RAIN DURING
THE PERIOD WILL BE WED (LIKELY POPS FOR NW QUADRANT OF FA) WITH A
SFC TROF OVR THE MID ATLANTIC...DECENT FORCING ALOFT...AND A VERY
MOIST ATM. SEASONABLE TEMPS CONTINUE WED AND THU...HIGHS STILL IN
THE UPR 70S TO LWR 80S.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE LATEST NUMERICAL GUIDANCE IS SUGGESTING THAT THE PERSISTENT
UPPER LOW MAY LINGER INTO FRIDAY. HOWEVER...AT THIS POINT NOTHING
MORE THAT A SLIGHT CHANCE POP IS NECESSARY. AN UPPER HIGH THEN
BUILDS OVER THE OHIO VALLEY FOR THE MEMORIAL DAY WEEKEND. GIVEN
WHERE THE HIGH SETS UP IT IS POSSIBLE SOME CONVECTION COULD ROUND
THE TOP OF THE RIDGE AND APPROACH THE LOCAL AREA IN MID-LEVEL NNW
FLOW. THE LARGE MAJORITY OF THE TIME IS EXPECTED TO BE DRY AND THERE
IS BASICALLY NO SKILL IN FORECASTING MCS ACTIVITY IN THE MEDIUM
RANGE. TEMPERATURES SHOULD BE ABOVE SEASONAL AVERAGES WITH HIGHS IN
THE MID 80S TO NEAR 90 (SLIGHTLY COOLER ALONG THE COASTS WITH LIGHT
ONSHORE FLOW). LOW TEMPERATURES SHOULD GENERALLY BE IN THE 60S.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
VFR CONDITIONS AT MOST TERMINALS AS OF 06Z...WITH THE EXCEPTION OF
SOME MVFR/TEMPO IFR CONDS AT KSBY/KECG. WEAK LOW PRESSURE PERSISTS OVER
THE REGION WITH MOSTLY LIGHT WINDS FROM THE E-SE. BIGGEST CONCERN
EARLY THIS MORNING IS W/THE CHANCE OF MORE WIDESPREAD IFR
CONDITIONS DUE TO PLENTY OF LOW LEVEL MOISTURE. ACCORDINGLY HAVE
GONE WITH LOWERING CIGS TO LOW MVFR/IFR RANGE AT RIC/ORF/PHF TOWARDS
DAWN. HAVE ALSO ALLOWED FOR SOME PATCHY DENSE FOG AT ALL SITES
AFTER 08Z THROUGH JUST AFTER SR.

VFR CONDITIONS ARE EXPECTED BY MID TO LATE MORNING AS WINDS SHIFT
TO THE S-SW DURING THE LATE NIGHT TUESDAY AND OVERNIGHT HOURS WED
MORNING. MORE SHOWERS AND TSTMS POSSIBLE FOR TUE AFTN/EVENING
AFTER 18-20Z THROUGH EARLY EVENING AS WEAK INSTABILITY CONTINUES
OVER THE REGION, COURTESY OF APPROACHING UPPER TROUGH FROM THE
WEST.

OUTLOOK...SLOW MOVING UPPER SYSTEM WILL RESULT IN CONTINUED
UNSETTLED WEATHER WED AND THU...WITH THE POTENTIAL FOR FLIGHT
RESTRICTIONS IN PATCHY FOG EACH MORNING AND IN SCT CONVECTION EACH
AFTN. CLEARING FINALLY BUILDS IN FROM THE WEST FOR FRIDAY AND INTO
THE UPCOMING HOLIDAY WEEKEND.

&&

.MARINE...
THE LATEST SURFACE ANALYSIS SHOWS A RATHER NEBULOUS SURFACE PATTERN
ACROSS THE LOCAL MARNIE AREA AND HENCE WEAK FLOW. THIS GENERAL FLOW
PATTERN SHOULD CONTINUE THROUGH MUCH OF THE WEEK WITH S OR SE FLOW
AOB 10KT. AN AREA OF LOW PRESSURE (NOT TS ALBERTO) PRESENTLY WELL
EAST OF THE NC COAST WILL MOVE NNE ON A TRAJECTORY TOWARD NS THROUGH
TUESDAY. WNA WAVE SHOWS SWELL ASSOCIATED WITH THIS LOW AFFECTING THE
MARINE AREA TUESDAY INTO TUESDAY NIGHT WITH SEAS AOA 5FT GENERALLY
OUT PAST 5-10NM. AN SCA FOR HAZARDOUS SEAS WILL BE RAISED FROM 6AM
TUESDAY TO 6AM WEDNESDAY. OTHERWISE...SEAS SHOULD DROP BELOW SCA FOR
THE REMAINDER OF THE WEEK. UNSETTLED CONDITIONS SHOULD PERSIST MUCH
OF THE WEEK WITH A CHANCE FOR MAINLY AFTERNOON AND EVENING
THUNDERSTORMS.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 6 AM THIS MORNING
     TO 6 AM EDT WEDNESDAY FOR ANZ650-652-654-656-658.

&&

$$
SYNOPSIS...MAS
NEAR TERM...MPR/LSA
SHORT TERM...MAS
LONG TERM...AJZ
AVIATION...MAM
MARINE...AJZ








AREA FORECAST DISCUSSION

NWS BILLINGS MT

 338 AM MDT TUE MAY 22 2012

.SHORT TERM...VALID FOR TDY AND WED...

120KT H3 JET CURRENTLY NOSING THROUGH OR INTO SOUTHERN ID...WITH A
LARGE AREA OF SHOWERS AFFECTING WESTERN INTO NORTH CENTRAL MONTANA
TONIGHT. PV MAX APPROACHING WEST YELLOWSTONE IS ENHANCING THE
SHOWERS IN OUR WEST EARLY THIS MORNING...AND PER THIS TREND AND
LATEST RUC EXPECT A GOOD CHANCE OF SHOWERS ACROSS OUR WEST AND
NORTHWEST PARTS THROUGH AROUND 13Z. SCATTERED SHOWERS SHOULD PUSH
THRU THE BILLINGS AREA BETWEEN 10-13Z. HAVE MADE SOME ADJUSTMENTS
TO THE 6-12Z POP GRID TO COVER THIS ACTIVITY...WHICH IS PUSHING A
BIT MORE AGGRESSIVELY TO THE EAST SOONER THAN PREVIOUSLY THOUGHT.

NEXT SHORTWAVE EMBEDDED IN THE QUICKENING PACIFIC FLOW IS STILL
OFF THE COAST...AND WILL MOVE INLAND AND AFFECT OUR AREA LATER
TODAY AND TONIGHT. FRONTOGENESIS WILL INCREASE BEHIND THE CURRENT
ENERGY AND AHEAD OF THIS NEXT WAVE...IN AN AREA OF GOOD MOISTURE
TRANSPORT. FURTHERMORE...THERE IS AN AREA OF WEAK PRESSURE FALLS
IN IDAHO ASSOCIATED WITH THE JET STREAK...AND THIS MAY REDUCE/LAG
THE DOWNSLOPING WINDS EXPECTED WITH THE COLD ADVECTION SET TO
OCCUR TODAY. SO...EXPECT MORE SHOWERS TO DEVELOP TO OUR WEST THIS
MORNING AND SPREAD INTO OUR AREA FROM LATE MORNING INTO THE
EVENING...WITH A GRADUAL SAGGING TO THE SOUTH AS STRONGER
FRONTOGENESIS AND JET DIVERGENCE DOES THE SAME. HAVE RAISED POPS
A BIT MORE OVER OUR MOUNTAINS PER THE FAVORABLE OROGRAPHIC
FLOW...MOISTURE AND INSTABILITY. 700MB TEMPS WILL FALL TO NEAR -4C
TONIGHT...THUS EXPECT SOME SNOW ACCUMULATION OVER THE WEST SLOPES.

CYCLONIC FLOW WITH UPPER LEVEL TROFFING AND RELATIVELY COLD TEMPS
ALOFT...AND ADDITIONAL SHORTWAVE ENERGY EMBEDDED IN THE PACIFIC
FLOW...WILL KEEP SHOWERY WEATHER GOING THROUGH WEDNESDAY AND
WEDNESDAY NIGHT. LOW LEVEL DOWNSLOPE WINDS WILL LIMIT OUR PCPN
COVERAGE TO SCATTERED ACROSS THE LOWER ELEVATIONS...GREATEST WITH
DAYTIME HEATING ON WEDNESDAY...BUT OUR WEST SLOPES WILL CONTINUE
TO FAVORED WITH A MIX OF RAIN AND SNOW SHOWERS. HAVE RAISED POPS
OVER OUR WESTERN HIGH TERRAIN AND GIVEN ELEVATIONS ABOVE 7KFT A
LITTLE SNOW ACCUMULATION EACH PERIOD. AT THE VERY LEAST...THE
ONSET OF THIS MUCH COOLER PATTERN WILL STOP WHAT HAS BEEN AN EARLY
HIGH ELEVATION SNOW MELT FOR A FEW DAYS.

AS FOR TEMPERATURES...HIGHS TRICKY TODAY WITH MIXING/WARMING EARLY
ON BECOMING OFFSET BY COLD ADVECTION WHICH WILL INCREASE BY LATE
MORNING AND INTO THE AFTERNOON. EXPECT TEMPS TO DROP INTO THE 50S
WITH THE SHOWER ACTIVITY. COOL POST FRONTAL AIRMASS WILL BE IN
PLACE FOR WEDNESDAY. WITH WEST WINDS AND GOOD MIXING WE SHOULD
STILL GET INTO THE UPPER 50S TO MID 60S ACROSS THE PLAINS...THE
BEGINNING OF AN EXTENDED PERIOD OF BELOW NORMAL TEMPERATURE DAYS.

JKL

.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...

EXTENDED FORECAST THROUGH THE HOLIDAY WEEKEND CONTINUES TO LOOK
UNSEASONABLY COOL AND WET. MODEL AGREEMENT HAS TAKEN A HIT WITH
THE LATEST RUNS AS THE GFS HAS TRENDED LESS AMPLIFIED DESPITE THE
PRESENCE OF A VERY STRONG DOWNSTREAM RIDGE COMPARED TO OTHER
MODELS WHICH REMAIN SIMILAR TO LAST NIGHTS AND MONDAY MORNINGS
RUNS.

THURSDAY...COLDER LOW LEVEL AIR BUILDS IN FROM CANADA WITH SOME
SEMBLANCE OF UPSLOPE FLOW AND FRONTOGENESIS HELPING TO GENERATE
SHOWERS ACROSS THE AREA. TEMPERATURES LOOK QUITE COOL WITH
FORECAST HIGHS IN THE 50S...THOUGH THIS MAY BE TOO WARM GIVEN
COLD ADVECTION AND PLENTY OF CLOUDS/PRECIPITATION. FLOW ALOFT
BEGINS TO BACK TO THE SOUTHWEST LATE IN THE DAY WHICH WILL
ENHANCE MID LEVEL OVER RUNNING KEEPING PRECIPITATION GOING INTO
THE NIGHT WITH THE HEAVIEST ACCUMULATIONS LIKELY OVER SOUTHERN
ZONES.

FRIDAY THROUGH SUNDAY...TRACK AND TIMING OF UPPER LOW CONTINUE TO
BE PROBLEMATIC WITH OPERATIONAL MODELS AND ENSEMBLE MEAN
SOLUTIONS CHANGING RUN TO RUN. THE ECMWF LOOKS LIKE THE MOST
STABLE SOLUTION AT THIS POINT AND ITS AMPLIFIED SOLUTION IS
SUPPORTED BY STRONG RIDGING DOWNSTREAM OVER THE EASTERN US. 06Z
NAM HAS TRENDED TOWARD THE 00Z ECMWF THIS MORNING AS WELL WITH
ADDITIONAL SUPPORT FROM THE CANADIAN SOLUTIONS. THE GFS WENT MUCH
LESS AMPLIFIED WITH THE UPPER LOW AND BLEEDS ENERGY OUT OF THE
SYSTEM ACROSS WYOMING KEEPING HEAVIEST PRECIPITATION TO THE SOUTH
OF THE AREA...THOUGH STILL SUPPORTING HIGH POPS JUST LESS QPF FOR
FRIDAY AND SATURDAY. GENERALLY PREFER A MORE AMPLIFIED SOLUTION
AS LONG AS THE DOWNSTREAM RIDGING REMAINS IN PLACE THUS
DISCOUNTING THE GFS AT THIS TIME AND LEANING TOWARD AN
ECMWF/ENSEMBLE MEAN SOLUTION. THIS SOLUTION PRODUCES A DEEP
SOUTHERLY DIFFLUENT FLOW OVER THE AREA FRIDAY INTO SATURDAY AS
THE UPPER LOW MOVES FROM CENTRAL CALIFORNIA INTO CENTRAL MONTANA.
A SURFACE LOW DEVELOPS OVER NORTHEAST WYOMING ALLOWING STRONG
ISENTROPIC LIFT IN THE LOWER LEVELS TO DEVELOP OVER MOST OF THE
AREA SUPPORTING 1 TO 2 INCH TYPE PRECIPITATION AMOUNTS ACROSS THE
AREA. EASTERLY SURFACE GRADIENT WILL ALSO SUPPORT UPSLOPE INTO
AREA MOUNTAINS AND FOOTHILLS WHICH COMBINED WITH DIVERGENCE ALOFT
WILL ENHANCE PRECIPITATION NEAR THE MOUNTAINS. AS A RESULT HAVE
LIKELY OR BETTER POPS IN THE MOUNTAINS WITH HIGH CHANCE TO LIKELY
POPS FOR THE LOWER ELEVATIONS. CURRENTLY HAVE TEMPERATURES
FORECAST IN THE 50S ACROSS MOST OF THE AREA FRIDAY AND
SATURDAY...BUT TEND TO THINK THIS WILL BE TOO WARM SHOULD THE
ECMWF SOLUTION VERIFY ESPECIALLY SATURDAY. WITH UPPER LOW AND
PLENTY OF PRECIPITATION ON SATURDAY HIGHS COULD STAY IN THE LOW
TO MID 40S...WITH 30S IN THE FOOTHILLS.

SNOW...FREEZING LEVELS WILL BE QUITE LOW FRIDAY MORNING
SUPPORTING A MIX OF RAIN AND SNOW FOR WESTERN FOOTHILLS
LOCATIONS. AS THE UPPER LOW MOVES INTO THE AREA FRIDAY NIGHT
EXPECT ADDITIONAL LOWERING OF FREEZING LEVELS WITH THE POTENTIAL
FOR HEAVY SNOW OVER AREA MOUNTAINS AS 700MB TEMPERATURES DROP TO
AROUND -10C. THIS WOULD BRING THE CHANCE FOR ACCUMULATING SNOW IN
THE RED LODGE...NYE AND POSSIBLY LIVINGSTON AREAS FRIDAY
NIGHT/SATURDAY MORNING...ALONG WITH HEAVY SNOW ALONG THE
BEARTOOTH PASS. WENT AHEAD AND BUMPED QPF AND SNOW ACCUMULATIONS
UP FOR THESE PERIODS BUT AMOUNTS ARE DEPENDENT ON A FAVORABLE
TRACK TO THE UPPER LOW AND COULD BE OVERDONE IF THE LOW TRACK IS
FURTHER WEST OR SOUTH. ANYONE PLANNING TRAVEL TO THE HIGH
COUNTRY...INCLUDING ALONG THE BEARTOOTH HIGHWAY...SHOULD REMAIN
ALERT TO THE LATEST FORECASTS AND SHOULD PROBABLY PLAN ON WINTER
DRIVING CONDITIONS.

SUNDAY...MOST OF THE MODELS INDICATING DOWNSLOPE WINDS WILL SCOUR
OUT PRECIPITATION SUNDAY AFTERNOON...THUS HAVE TRENDED POPS DOWN
SUNDAY INTO MONDAY. HOWEVER THERE IS A CHANCE THAT A MORE
AMPLIFIED SYSTEM WILL MOVE SLOWER LINGERING PRECIPITATION INTO
MONDAY...SO HAVE NOT GONE DRY. NORTHWEST WINDS WILL BECOME GUSTY
SUNDAY AFTERNOON INTO SUNDAY NIGHT WHICH WILL HELP HOLD
TEMPERATURES WARMER THAN SATURDAY NIGHT.

MONDAY THROUGH WEDNESDAY...ECMWF INDICATING ZONAL FLOW WHILE GFS
DRIVES ANOTHER PACIFIC SYSTEM INTO THE AREA. KEEPING SOME LOW
POPS IN THE FORECAST ALONG WITH WARMER TEMPERATURES FOR NOW.
CHAMBERS

&&

.AVIATION...

UPPER LEVEL STORM SYSTEM IS MOVING INTO WESTERN AREAS THIS
MORNING WITH SCATTERED RAIN SHOWERS. LOCAL MVFR CONDITIONS ARE
EXPECTED FROM KBIL WEST TO KLVM THROUGH 18Z. THIS AFTERNOON MVFR
OR LOWER CONDITIONS WILL BECOME PREDOMINANT WEST OF A ROUNDUP TO
SHERIDAN WYOMING LINE...WITH SCATTERED SHOWERS AND THUNDERSTORMS
TO THE EAST RESULTING IN LOCAL MVFR CONDITIONS FOR KMLS.
OCCASIONAL MOUNTAIN OBSCURATION THIS MORNING WILL BECOME
PREDOMINANT THIS AFTERNOON AND CONTINUE THROUGH TONIGHT.
CHAMBERS

&&

.PRELIMINARY POINT TEMP/POPS...

    TDY WED     THU     FRI     SAT     SUN     MON
-------------------------------------------------------
BIL 071 045/062 042/055 040/053 040/054 040/065 044/068
    7/T 44/T    36/T    55/T    66/T    53/T    22/T
LVM 062 037/055 034/052 033/049 034/052 032/061 038/066
    7/T 45/T    36/T    56/T    66/T    73/T    22/T
HDN 075 044/064 042/056 040/056 041/059 041/067 044/069
    7/T 54/T    46/T    55/T    66/T    52/T    22/T
MLS 077 047/067 044/057 042/056 043/059 043/066 045/069
    6/T 42/W    34/T    34/T    55/T    53/T    22/T
4BQ 080 047/064 043/056 040/055 044/062 042/067 044/071
    5/T 63/T    34/T    44/T    75/T    53/T    22/T
BHK 081 045/064 041/060 040/053 044/057 043/064 044/069
    5/T 42/W    24/T    34/T    55/T    53/T    22/T
SHR 077 042/060 039/054 037/053 039/060 039/063 040/067
    4/T 64/T    45/T    45/T    66/T    53/T    22/T

&&

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.

&&

$$
WEATHER.GOV/BILLINGS







AREA FORECAST DISCUSSION

NWS GLASGOW MT

 1027 PM MDT MON MAY 21 2012

.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH WEDNESDAY...
10 PM UPDATE...AREAS OF SHOWERS CONTINUE TO MOVE INTO THE WESTERN
AREAS AND WEAKEN AS THEY PUSH EAST. KEPT HIGH POPS FOR THE WEST
AND SLIGHT OR ISOLATED POPS IN THE EAST. DROPPED THUNDER FOR THE
NIGHTTIME HOURS. MODELS SHOW THAT THUNDER DEVELOPING MID DAY OVER
THE FORECAST AREA AND SPREADING EAST DURING THE EARLY
AFTERNOON...AND BECOMING SEVERE IN NORTH DAKOTA. ANY SLOWING UP OF
THE FRONT COULD BRING A SHOT OF SEVERE THUNDER TO PLENTYWOOD-
SIDNEY-WIBAUX AREAS IN THE AFTERNOON. BUFR NAM SOUNDINGS HAVE THE
INVERTED V... PW/S NEARING 1.00... AND A GOOD TURN IN THE WIND
FIELD FROM SFC TO 850 MB. WILL NOT UPDATE DAY TWO OF THE
FORECAST...BUT COULD BE BRIEFLY A CONCERN IN THE EARLY AFTERNOON
FOR THE FAR EASTERN ZONES.                   PROTON

8 PM UPDATE...AN ARC OF SHOWERS WITH A FLASH OR TWO OF THUNDER
CONTINUE TO PUSH EAST ACROSS THE CMR AND GARFIELD COUNTY THIS
EVENING. THE ARC OF SHOWERS/STORMS HAS PRODUCED 30 TO 50 MPH WIND
GUSTS AS IT PASSES OVER OBSERVATION SITES. THE LATEST HRRR MODEL
PUSHES THIS ARC THROUGH AND DIMINISHES IT THROUGH 10 PM. WILL HAVE
TO WATCH THE AREA OF SHOWERS TO THE EAST OF GREAT FALLS... THE
HRRR BRINGS THAT THROUGH THE WESTERN CMR AND UP FORT PECK LAKE
THROUGH MIDNIGHT. MAY HAVE TO UPDATE AT 10 PM TO BETTER DEFINE
OVERNIGHT POPS AND QPF.               PROTON

6 PM UPDATE...AN AREA OF THUNDERSTORMS HELD TOGETHER OVER CENTRAL
MONTANA AND IS MOVING INTO THE WESTERN ZONES. UPDATED THE FORECAST
TO ADD GUSTY WINDS SINCE UPSTREAM OBSERVATIONS HAVE SOME GUSTS TO
30 MPH. INCREASED POP COVERAGE FOR THE CMR AND THE WEST SIDE OF
FORT PECK LAKE WITH THE HRRR MODEL HITTING THIS AREA HARDER WITH
RAINFALL THIS EVENING.             PROTON

UPPER TROF OFF THE PACIFIC NORTHWEST EXPECTED TO TRANSITION INTO
MONTANA DURING THE SHORT TERM. SOUTHWEST FLOW ALOFT ALREADY
PUSHING INCREASED MOISTURE INTO THE WESTERN PART OF THE STATE AND
A FEW HIGH BASED THUNDERSTORMS ARE MOVING ACROSS CENTRAL MONTANA
THIS AFTERNOON. AIRMASS OVER EASTERN MONTANA STILL QUITE DRY AND
AFFECTED BY PROXIMITY OF RIDGE AXIS BUT JET STREAK PUSHING ACROSS
CENTRAL MONTANA INTO SOUTHERN SASKATCHEWAN OVERNIGHT WILL HELP
SPREAD THUNDERSTORMS OVER THE NORTHWEST ZONES. JET ALSO PUSHES
COLD FRONT ACROSS THE STATE OVERNIGHT AND WITH COLD AIR ADVECTION
...TIGHTENING PRESSURE GRADIENT AND DOWNSLOPE FLOW WITH JET EXPECT
WINDS TO INCREASE ACROSS THE REGION ON TUESDAY. SHOULD BE STRONG
ENOUGH FOR LAKE WIND ADVISORY BY MIDDAY...EXTENDING INTO THE
EVENING HOURS IF NOT THROUGH THE NIGHT.

STRONG WESTERLIES AND CAA BEHIND THE FRONT WILL RESULT IN SOME
INHIBITION OF SHOWERS FOR TUESDAY MORNING. ANOTHER JET STREAK
PUSHES ACROSS NORTHERN WYOMING IN THE AFTERNOON...WHICH COULD HELP
DEVELOP CONVECTION OFF THE HIGHER TERRAIN IN SOUTHWEST MONTANA AND
PUSH IT INTO THE PLAINS.

BY WEDNESDAY THE BETTER LIFT MOVES EAST AS THE UPPER TROF SLIDES
INTO MONTANA. COLD AIR ALOFT COULD RESULT IN ENOUGH INSTABILITY
FOR A FEW SHOWERS BUT OVERALL TREND WILL BE DRY AND COOL. LOW
LEVELS MIX ENOUGH THAT ANOTHER LAKE WIND ADVISORY MAY BE NEEDED.
EBERT


.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...

MADE SOME ADJUSTMENTS TO THE LONG TERM FORECAST PERIOD. A BROAD
UPPER LEVEL TROUGH WILL DOMINATE THE WEATHER PATTERN OVER THE
ROCKIES...INTER-MOUNTAIN WEST...AND NORTHERN HIGH PLAINS THROUGH
MOST OF THE EXTENDED PERIOD. LOOKS LIKE IT UNFOLD IN TWO PHASES.
FIRST...THE LONG AND BROAD UN-AMPLIFIED TROUGH WILL DROP THROUGH
THE NORTHERN ROCKIES AND NORTHERN HIGH PLAINS FROM WEDNESDAY NIGHT
THROUGH THURSDAY NIGHT.

FROM THURSDAY NIGHT ONWARD...AN UPSTREAM UPPER LEVEL LOW CENTER
LOBE BECOMES THE STAR OF THE SHOW AS IT QUICKLY DEEPENS AND DIGS
DOWN OVER THE CASCADE MOUNTAIN RANGE...BOTTOMING OUT OVER LAS
VEGAS...THEN QUICKLY CHANGING COURSE AND HEADING NORTHEAST THROUGH
SUNDAY...EVENTUALLY MOVING DIRECTLY OVER OUR CWA.

MODELS ARE IN MODERATELY GOOD AGREEMENT WITH THIS GENERAL WEATHER
PATTERN...BUT ANY MORE DETAILS GET KIND OF MUDDLED. ESPECIALLY
WITH THE NORTHWARD PROGRESSION OF THIS LATE UPPER LOW THROUGH THE
WEEKEND. THE GFS DIFFUSES AND OPENS UP THIS LOW CENTER QUITE
QUICKLY...BUT THE EC HOLDS ONTO IT AND EVEN DEEPENS IT OVER OUR
CWA WHICH WOULD RESULT IN MUCH COLDER TEMPERATURES THAN WE HAVE
CURRENTLY FORECASTED.

TRIED TO SHOW AN EXTENDED MODEL BLEND...BUT DID NOT GIVE EQUAL
WEIGHT TO THE EXTREME EC OUTLIER AND WOULD ADVISE DOING SO UNTIL
EXTENDED MODELS SHOW BETTER AGREEMENT.

OVERALL...EXPECT ALTERNATING PERIODS OF RAIN SHOWERS AND DRY SLOTS
WITH GENERALLY COOLER TEMPERATURES AS THIS LARGE UPPER TROUGH
SYSTEM SPREADS ACROSS MOST OF THIS PORTION OF THE CONTINENT.
BMICKELSON

PREVIOUS LONG TERM DISCUSSION...MODELS TAKE ONE UPPER TROUGH TO
THE EAST THURSDAY AND THURSDAY NIGHT WHILE DIGGING ANOTHER OVER
THE PACIFIC NORTHWEST. WHILE THE BULK OF THE MOISTURE WITH
THURSDAY`S TROUGH IS EXPECTED TO BE TO THE EAST...THERE WILL BE
ENOUGH LINGERING MOISTURE AND INSTABILITY TO WARRANT A CHANCE OF
SHOWERS.

ON FRIDAY...THE FORECAST WILL BE BETWEEN SYSTEMS IN A SOUTHWEST
FLOW ALOFT AS A CLOSED LOW DEVELOPS IN CALIFORNIA IN THE WEST
COAST UPPER TROUGH. MODELS DIFFER BETWEEN A DRY SW FLOW (GFS) AND
MOIST SW FLOW (ECMWF) ALOFT. WILL MAINTAIN EITHER A CHANCE OR
SLIGHT CHANCE OF SHOWERS.

MODELS GRADUALLY LIFT THIS LOW NORTH OVER THE WEEKEND AND BRING IT
ACROSS MONTANA ON SUNDAY. IF THIS FORECAST HOLDS TRUE...IT COULD
BE A VERY WET WEEKEND ACROSS THE REGION. WILL MAINTAIN A CHANCE
OF SHOWERS FOR NOW UNTIL BETTER RUN TO RUN AGREEMENT IS
MAINTAINED.

THE LOW LIFTS NORTH NEXT MONDAY DIMINISHING THE CHANCE OF SHOWERS. FORRESTER


&&

.AVIATION...
AN APPROACHING PACIFIC LOW PRESSURE SYSTEM WILL BRING INCREASED
CLOUDINESS AND RAIN SHOWERS TO NORTHEAST MONTANA TOWARD THE END OF
THIS TAF PERIOD. VFR CONDITIONS ARE EXPECTED TO PREVAIL WITH ONE
BRIEF EXCEPTION...KGGW MAY SEE MVFR CONDITIONS WITH A BRIEF RAIN
SHOWER TONIGHT AND AGAIN BY MID DAY TUESDAY. A COLD FRONT WILL
PUSH RAIN SHOWERS AND POSSIBLY A FEW THUNDERSTORMS THROUGH THE
ENTIRE REGION. WINDS WILL SHIFT AROUND TO COME FROM THE NORTHWEST AND
WEST DURING THE LATE MORNING HOURS ON TUESDAY...THEN INCREASE INTO
THE 25G35KT RANGE BY MID DAY. OVERALL...EXPECT INCREASED CROSSWIND
CONCERNS FOR NORTH TO SOUTH ORIENTED RUNWAYS DURING THE MID DAY
AND AFTERNOON HOURS ON TUESDAY WITH BRIEF MODERATE RAIN SHOWERS.
BMICKELSON


&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...
LAKE WIND ADVISORY FROM 10 AM TO 9 PM MDT TUESDAY FOR FORT PECK
LAKE.

&&

$$

WEATHER.GOV/GLASGOW






AREA FORECAST DISCUSSION

NWS HASTINGS NE

 1214 AM CDT TUE MAY 22 2012

.AVIATION...06Z KGRI TAF. VFR CEILING/VISIBILITY WILL HOLD FIRM
THROUGH THE PERIOD...WITH NOTHING MORE THAN VARYING DEGREES OF
PASSING MID AND HIGH LEVEL CLOUDS. HOWEVER...STRONG SOUTHERLY WIND
WILL BE AN ISSUE DURING THE PERIOD. INITIALLY BEFORE
SUNRISE...SUSTAINED SPEEDS WILL AVERAGE NEAR 14KT...BUT A STEADY
RAMP-UP WILL TAKE PLACE DURING THE DAY...WITH SUSTAINED SPEEDS
TOPPING OUT NEAR 23KT AND GUST POTENTIAL TO NEAR 32KT...WHICH IS A
SLIGHT INCREASE OVER SPEEDS INDICATED IN THE PREVIOUS TAF
ISSUANCE. EVEN AFTER NIGHTFALL TUESDAY EVENING...GUSTS TO TO
AROUND 26KT WILL PERSIST. LOOKING ABOVE THE SURFACE...A
STRENGTHENING LOW LEVEL JET WILL RESULT IN ENOUGH SPEED SHEAR IN
THE LOWEST 1500 FT AGL TO JUSTIFY A MENTION OF LOW LEVEL WIND SHEAR
THROUGH THE FIRST SEVERAL HOURS OF THE PERIOD. FINALLY...WILL
INSERT A VICINITY SHOWER MENTION FOR THE FIRST SEVERAL HOURS OF
THE PERIOD AS WELL TO ACCOUNT FOR THE POSSIBILITY OF A BRIEF
SHOWER MOVING IN FROM THE NORTHWEST.

&&

.PREV DISCUSSION... /ISSUED 1148 PM CDT MON MAY 21 2012/

UPDATE...EVENING UPPER AIR ANALYSIS INDICATES RIDGING OVER THE
WESTERN CONUS WITH TROUGHING OVER THE EAST. MID AND UPPER LEVEL
FLOW OVER THE CENTRAL PLAINS REMAIN FROM THE NORTHWEST AS A
RESULT. THAT BEING SAID...THE PRIMARY AXIS OF MID AND UPPER LEVEL
JET ENERGY IS RELEGATED TO THE NORTHWESTERN CONUS THUS LEAVING
TROPOSPHERIC FLOW FAIRLY WEAK OVER OUR AREA...WITH THE ONLY
EXCEPTION BEING CLOSER TO 850MB WHERE A 20-30KT LOW LEVEL JET
STREAK IS NOTED EXTENDING FROM WESTERN KANSAS INTO WESTERN
NEBRASKA. WATER VAPOR IMAGERY SHOWS INCREASED VALUES OF MID LEVEL
MOISTURE FLOWING INTO THE WESTERN CONUS FROM THE PACIFIC...SOME OF
WHICH IS BEGINNING TO SPILL OVER THE WESTERN CONUS RIDGE THUS
RESULTING IN INCREASING MID TO HIGH LEVEL CLOUDS ACROSS THE
NORTHERN AND CENTRAL PLAINS. WATER VAPOR IMAGERY ALSO SHOW A MID
LEVEL LOW TO THE SOUTHEAST OF THE ALEUTIAN ISLANDS...WITH A MID
LEVEL SHORT WAVE PIVOTING TO THE SOUTH OF THE LOW. AT THE SURFACE
A RIDGE OF HIGH PRESSURE IS NOTED OVER THE MISSISSIPPI
VALLEY WITH TROUGHING OVER THE FRONT RANGE...THUS HELPING PROMOTE
SOUTH/SOUTHEASTERLY LOW LEVEL FLOW ACROSS THE CENTRAL PLAINS.

KUEX CONTINUES TO INDICATE THE LEADING EDGE OF CONVECTIVE ACTIVITY
EXTENDING FROM NEAR KODX TO NEAR BEAVER CITY AND MOVING SOUTHEAST. THIS
ACTIVITY IS LIKELY BEING REINFORCED BY LOW LEVEL THERMAL ADVECTION
ALONG THE AXIS OF THE LOW LEVEL JET CURRENTLY NEAR THE AREA. SHORT
TERM GUIDANCE PER THE RAP AND NAM SUGGEST THIS LOW LEVEL JET WILL
PUSH EAST AND BECOME MORE ORIENTED FROM THE SOUTHWEST TO NORTHEAST
ACROSS OUR AREA THROUGH 12Z. GIVEN THIS...IT IS AT LEAST POSSIBLE
ISOLATED TO PERHAPS SCATTERED PRECIPITATION WILL PERSIST OVER
PORTIONS OF THE CWA THROUGH THE OVERNIGHT HOURS. SPC
MESO-ANALYSIS SUGGESTS THE PRIMARY INSTABILITY AXIS EXISTS TO OUR
WEST OVER THE HIGH PLAINS...BUT IT IS POSSIBLE THIS INSTABILITY
AXIS...WITH PERHAPS AROUND 100J/KG DEEP LAYER MUCAPE...COULD
SPREAD EAST MORE INTO OUR AREA AS MOISTURE ADVECTION ALONG THE LOW
LEVEL JET AXIS ALSO PUSHES INTO OUR AREA. GIVEN ALL THIS...WENT
AHEAD AND EXTENDED SLIGHT CHANCE POPS ACROSS ROUGHLY THE
NORTHWESTERN HALF OF THE CWA THROUGH 12Z...WHICH MATCHES UP FAIRLY
CLOSELY WITH THE ANTICIPATED POSITION OF THE LOW LEVEL JET AXIS
THROUGH 12Z. ALTHOUGH INSTABILITY IS EXTREMELY LIMITED OVER OUR
AREA AT THIS HOUR...GIVEN THE POSSIBILITY OF SOMEWHAT INCREASING
INSTABILITY ACROSS OUR AREA...WENT AHEAD AND ALSO KEPT THE
ISOLATED THUNDER MENTION IN THE FORECAST FOR TONIGHT.

PREV DISCUSSION... /ISSUED 1021 PM CDT MON MAY 21 2012/

UPDATE...UPDATED THE FORECAST THIS EVENING FOR SOME POSSIBLE
LIGHT PRECIPITATION IN OUR FAR WEST/NORTHWEST CWA AS THUNDERSTORMS
TO THE WEST DWINDLE. LITTLE SHEAR AND INSTABILITY TO HELP SUPPORT
THESE CELLS AND THEY SHOULD DIE OUT IN THE NEXT FEW HOURS.

PREV DISCUSSION... /ISSUED 403 PM CDT MON MAY 21 2012/

SHORT TERM...TONIGHT AND TOMORROW.

A QUICK UPPER LEVEL ANALYSIS INDICATES AN UPPER LEVEL CLOSED LOW
PUSHING OFF THE EAST COAST WHILE THE TROUGH AXIS REMAINS ORIENTED
ACROSS THE MISSISSIPPI VALLEY REGION. BUILDING IN ACROSS THE WESTERN
HALF OF THE CONUS...AN UPPER LEVEL RIDGE HAS BEGUN TO DOMINATE MUCH
OF THE ROCKY MOUNTAIN WEATHER. SEVERAL WEAK SHORT WAVE PERTURBATIONS
REMAIN IN THE DOMINATE FLOW...INCLUDING ONE ACROSS THE FRONT RANGE.
A SURGE OF MOISTURE IN THE MID LEVELS HAS POOLED UNDER AN AREA OF
HIGH PRESSURE ACROSS THE TEXAS PANHANDLE...BUT SOME SCANT AMOUNTS
HAVE SURGED AS FAR NORTH AS SOUTH DAKOTA ACROSS WESTERN NEBRASKA. AT
THE SURFACE...A LARGE AREA OF HIGH PRESSURE HAS LAGGED ACROSS THE
CENTRAL CONUS STRETCHING FROM CANADA TO TEXAS...WHILE WEAK LOW
PRESSURE HAS BEGUN TO DEVELOP ACROSS THE FRONT RANGE.

BEGINNING THE SHORT TERM...THE PLAINS REMAIN UNDER THE INFLUENCE OF
THE INCOMING RIDGE AND ASSOCIATED SURFACE HIGH. THIS HIGH PRESSURE
SYSTEM WILL BEGIN TO SHIFT EASTWARD AS THE MAIN FOCUS OF THE SHORT
TERM SHIFTS TO THE INCOMING SURFACE LOW/TROUGH.

A FEW CONCERNS DURING THE OVERNIGHT PERIOD WILL BE THE INCREASE IN
THE LOW LEVEL JET OVERNIGHT. MODELS INCREASE 850 MB WINDS TO NEAR 40
KTS OVERNIGHT...WITH THE GFS AND THE ECMWF JET LOCATIONS ACROSS THE
WESTERN HALF OF THE STATE AND THE NAM A BIT FURTHER EAST. BOTH THE
NAM AND THE GFS SOLUTION GENERATE SOME POPS WITH THE LOW LEVEL
JET...HOWEVER...THE NAM MODEL REMAINS FURTHER WEST...WHILE THE GFS
GENERATES POPS ACROSS THE FORECAST AREA. THE 4 KM WRF MODEL DOES NOT
PICK UP ON ANY SUGGESTION OF POTENTIAL POPS DURING THE OVERNIGHT
PERIOD. DECIDED TO LEAVE THE OVERNIGHT PERIOD DRY...BUT THIS COULD
BE A CONCERN GIVEN THE LOW LEVEL JET AXIS.

LEADING TOWARDS THE DAYTIME HOURS ON TUESDAY...THE SURFACE TROUGH WILL
CONTINUE TO PUSH EASTWARD...HELPING TIGHTEN THE PRESSURE GRADIENT
ACROSS THE PLAINS. AS A RESULT...INCREASED SOUTH WINDS WILL BE
PREVALENT DURING THE LATE MORNING AND AFTERNOON HOURS ON TUESDAY.
MODELS TRENDS HAVE REMAINED FAIRLY CONSISTENT BETWEEN
RUNS...ALTHOUGH MODEL GUIDANCE AS BEEN TRENDING DOWN SINCE
PREVIOUS RUNS. GIVEN THAT MODELS AND GUIDANCE REMAIN ONLY MARGINAL
WIND ADVISORY AT BEST IN ONLY A FEW LOCATIONS...DECIDED TO OPT OUT
OF ISSUING A WIND ADVISORY AT THIS POINT.

REGARDING TEMPERATURES ON TUESDAY...AS THE UPPER LEVEL RIDGE BUILDS
ACROSS THE PLAINS AND BOUNDARY LAYER MIXING IS EXPECTED TO AT LEAST
850 MB IF NOT 800 MB...SEE NO REASON WHY WE CANNOT TAP INTO SOME
WARM TEMPERATURES. THE NAM AND THE ECMWF REMAIN IN GOOD AGREEMENT
WITH A TEMPERATURE GRADIENT FROM POSSIBLY THE LOW 90S OUT WEST TO
LOW 80S IN THE EAST...THUS SUGGESTING A GRADIENT OF ABOUT 7 TO 10
DEGREES. THE GFS SOLUTION REMAINS THE OUTLIER WITH A MUCH COOLER
GRADIENT WITH MID 80S OUT WEST AND MID 70S EAST. DECIDED TO LEAN
MORE WITH THE NAM/EC SOLUTION ALTHOUGH PORTIONS FARTHER WEST COULD
BE A BIT WARMER AND PORTIONS FARTHER EAST COULD BE A BIT COOLER THAN
FORECAST.

LONG TERM...00Z WED THROUGH MONDAY.  OFF AND ON CHANCES FOR
PRECIPITATION DURING THE EXTENDED WILL BE MAIN CONCERN AS PATTERN
BECOMES MORE ACTIVE.

WEAK MID LEVEL RIDGE SHOULD BEGIN TO SLIDE TO OUR EAST OVERNIGHT
TUESDAY AND LOW AMPLITUDE TROUGH BEGINS TO PUSH INTO THE NW U.S.
FIRST WAVE OF ENERGY WILL KICK OUT AND PUSH A COLD FRONT INTO THE
CENTRAL PLAINS DURING THE DAYTIME ON WED. SHOULD BE ENTERING THE NW
PART OF THE CWA BY SUNRISE WED AND PUSH THROUGH DURING THE DAY. NAM
MORE PROGRESSIVE THAN THE GFS WITH THIS FRONT. ALL MODELS SHOWING
DECENT CAP OVER THE SE HALF OF THE CWA DURING THE AFTERNOON AND
BANKING ON THIS FEATURE TO KEEP THUNDERSTORMS AT BAY DURING THE DAY.
CHANCES INCREASE ESPECIALLY IN THE NORTHERN PART OF THE CWA WED
EVENING AND OVERNIGHT AS MID LEVEL WAVE ROTATES THROUGH HELPING COOL
OFF MID LEVEL TEMPS ESPECIALLY IN THE NORTH. GFS AND OLD EC MODELS
DO SHOW THE BETTER JET SUPPORT TO BE JUST A LITTLE NORTH OF US WITH
RIGHT ENTRANCE AND LEFT EXIT REGIONS OF COUPLED JET FAVORING NW NEB.
MODELS ALSO SHOWING BEST MID LEVEL FRONTOGENESIS IN THIS AREA. WILL
WAIT TO GET A LOOK AT THE 12Z EC RUN BUT UNLESS IT SHOWS SOMETHING
DIFFERENT WILL KEEP WITH PREVIOUS THINKING OF BEST CHANCES FOR
THUNDERSTORMS IN THE NORTHWEST CWA AND DRY IN OUR FAR SOUTHEAST AS
CAP EXPECTED TO HOLD AND EVEN STRENGTHEN IN THAT AREA OVERNIGHT. IN
REGARDS TO SEVERE POTENTIAL...DEEP LAYER SHEAR AND MU CAPE WOULD
SUPPORT SOME SEVERE IN THE AREA.

THURSDAY/THUR NIGHT NOT REAL CLEAR CUT AS MODELS DIFFERING ON PRECIP
CHANCES. INITIAL THOUGHT IS THAT WE WON`T SEE MUCH DURING THE DAY
AND THEN CHANCES INCREASE SOME OVERNIGHT AS LOW LEVEL INCREASES.
HOWEVER WILL LEAVE AT LEAST A SMALL CHANCE IN THE NORTH DURING THE
DAYTIME.  AS FIRST WAVE EJECTS TO OUR NORTH...ANOTHER DEEPER MID
LEVEL LOW PRESSURE SYSTEM IS PROGGED TO DIG FROM THE PACIFIC NW ON
THURSDAY INTO SOUTHERN NEVADA BY SATURDAY BEFORE LIFTING NORTH INTO
SOUTHERN MANITOBA BY MONDAY NIGHT.  THIS TRACK IS MAINLY BASED OFF
THE EC AND IF IT HOLDS TRUE...WE SHOULD BE DRY DURING THE DAYTIME ON
FRIDAY WITH SHORT WAVE RIDGING. STILL LINGERING CHANCES FOR RAIN
FRIDAY NIGHT INTO SATURDAY NIGHT WITH WARM FRONT LIFTING NORTH AND
CYCLONIC FLOW IN THE UPPER LEVELS. SUNDAY COULD BE INTERESTING AS
COLD FRONT SWEEPS THROUGH DURING THE AFTERNOON. EARLY LOOK AT CAPE
AND SHEAR WOULD POINT TO SEVERE WEATHER CHANCE BUT AS USUAL THAT
WILL DEPEND ON TIMING OF A SYSTEM WHICH IS STILL SEVERAL DAYS AWAY.

AS FAR AS HIGH TEMPERATURES GO...WE WILL SEE SOME VARIATION AS
FRONTAL BOUNDARIES PUSH THROUGH...WITH THINGS A LITTLE COOLER ON
WED IN THE NORTH CWA AND THEN OVER THE ENTIRE AREA THURS AND FRI
BEFORE IT WARMS UP AGAIN ON SAT INTO SUNDAY AHEAD OF NEXT COLD
FRONT. NEXT MONDAY SHOULD ONCE AGAIN BE A LITTLE COOLER BEHIND THE
FRONT.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

AVIATION...PFANNKUCH
1148 PM UPDATE...BRYANT
1021 PM UPDATE...HEINLEIN
SHORT TERM...SALTZMAN
LONG TERM...EWALD






AREA FORECAST DISCUSSION

NWS HASTINGS NE

 1148 PM CDT MON MAY 21 2012

.UPDATE...EVENING UPPER AIR ANALYSIS INDICATES RIDGING OVER THE
WESTERN CONUS WITH TROUGHING OVER THE EAST. MID AND UPPER LEVEL
FLOW OVER THE CENTRAL PLAINS REMAIN FROM THE NORTHWEST AS A
RESULT. THAT BEING SAID...THE PRIMARY AXIS OF MID AND UPPER LEVEL
JET ENERGY IS RELEGATED TO THE NORTHWESTERN CONUS THUS LEAVING
TROPOSPHERIC FLOW FAIRLY WEAK OVER OUR AREA...WITH THE ONLY
EXCEPTION BEING CLOSER TO 850MB WHERE A 20-30KT LOW LEVEL JET
STREAK IS NOTED EXTENDING FROM WESTERN KANSAS INTO WESTERN
NEBRASKA. WATER VAPOR IMAGERY SHOWS INCREASED VALUES OF MID LEVEL
MOISTURE FLOWING INTO THE WESTERN CONUS FROM THE PACIFIC...SOME OF
WHICH IS BEGINNING TO SPILL OVER THE WESTERN CONUS RIDGE THUS
RESULTING IN INCREASING MID TO HIGH LEVEL CLOUDS ACROSS THE
NORTHERN AND CENTRAL PLAINS. WATER VAPOR IMAGERY ALSO SHOW A MID
LEVEL LOW TO THE SOUTHEAST OF THE ALEUTIAN ISLANDS...WITH A MID
LEVEL SHORT WAVE PIVOTING TO THE SOUTH OF THE LOW. AT THE SURFACE
A RIDGE OF HIGH PRESSURE IS NOTED OVER THE MISSISSIPPI
VALLEY WITH TROUGHING OVER THE FRONT RANGE...THUS HELPING PROMOTE
SOUTH/SOUTHEASTERLY LOW LEVEL FLOW ACROSS THE CENTRAL PLAINS.

KUEX CONTINUES TO INDICATE THE LEADING EDGE OF CONVECTIVE ACTIVITY
EXTENDING FROM NEAR KODX TO NEAR BEAVER CITY AND MOVING SOUTHEAST. THIS
ACTIVITY IS LIKELY BEING REINFORCED BY LOW LEVEL THERMAL ADVECTION
ALONG THE AXIS OF THE LOW LEVEL JET CURRENTLY NEAR THE AREA. SHORT
TERM GUIDANCE PER THE RAP AND NAM SUGGEST THIS LOW LEVEL JET WILL
PUSH EAST AND BECOME MORE ORIENTED FROM THE SOUTHWEST TO NORTHEAST
ACROSS OUR AREA THROUGH 12Z. GIVEN THIS...IT IS AT LEAST POSSIBLE
ISOLATED TO PERHAPS SCATTERED PRECIPITATION WILL PERSIST OVER
PORTIONS OF THE CWA THROUGH THE OVERNIGHT HOURS. SPC
MESO-ANALYSIS SUGGESTS THE PRIMARY INSTABILITY AXIS EXISTS TO OUR
WEST OVER THE HIGH PLAINS...BUT IT IS POSSIBLE THIS INSTABILITY
AXIS...WITH PERHAPS AROUND 100J/KG DEEP LAYER MUCAPE...COULD
SPREAD EAST MORE INTO OUR AREA AS MOISTURE ADVECTION ALONG THE LOW
LEVEL JET AXIS ALSO PUSHES INTO OUR AREA. GIVEN ALL THIS...WENT
AHEAD AND EXTENDED SLIGHT CHANCE POPS ACROSS ROUGHLY THE
NORTHWESTERN HALF OF THE CWA THROUGH 12Z...WHICH MATCHES UP FAIRLY
CLOSELY WITH THE ANTICIPATED POSITION OF THE LOW LEVEL JET AXIS
THROUGH 12Z. ALTHOUGH INSTABILITY IS EXTREMELY LIMITED OVER OUR
AREA AT THIS HOUR...GIVEN THE POSSIBILITY OF SOMEWHAT INCREASING
INSTABILITY ACROSS OUR AREA...WENT AHEAD AND ALSO KEPT THE
ISOLATED THUNDER MENTION IN THE FORECAST FOR TONIGHT.

&&

.PREV DISCUSSION... /ISSUED 1021 PM CDT MON MAY 21 2012/

UPDATE...UPDATED THE FORECAST THIS EVENING FOR SOME POSSIBLE
LIGHT PRECIPITATION IN OUR FAR WEST/NORTHWEST CWA AS THUNDERSTORMS
TO THE WEST DWINDLE. LITTLE SHEAR AND INSTABILITY TO HELP SUPPORT
THESE CELLS AND THEY SHOULD DIE OUT IN THE NEXT FEW HOURS.

PREV DISCUSSION... /ISSUED 700 PM CDT MON MAY 21 2012/

AVIATION...00Z KGRI TAF. VFR CONDITIONS WITH WIND KICKING UP ON
TUESDAY. ANY STORMS TO THE WEST SHOULD DIE OFF BEFORE REACHING THE
TERMINAL TONIGHT.

PREV DISCUSSION... /ISSUED 403 PM CDT MON MAY 21 2012/

SHORT TERM...TONIGHT AND TOMORROW.

A QUICK UPPER LEVEL ANALYSIS INDICATES AN UPPER LEVEL CLOSED LOW
PUSHING OFF THE EAST COAST WHILE THE TROUGH AXIS REMAINS ORIENTED
ACROSS THE MISSISSIPPI VALLEY REGION. BUILDING IN ACROSS THE WESTERN
HALF OF THE CONUS...AN UPPER LEVEL RIDGE HAS BEGUN TO DOMINATE MUCH
OF THE ROCKY MOUNTAIN WEATHER. SEVERAL WEAK SHORT WAVE PERTURBATIONS
REMAIN IN THE DOMINATE FLOW...INCLUDING ONE ACROSS THE FRONT RANGE.
A SURGE OF MOISTURE IN THE MID LEVELS HAS POOLED UNDER AN AREA OF
HIGH PRESSURE ACROSS THE TEXAS PANHANDLE...BUT SOME SCANT AMOUNTS
HAVE SURGED AS FAR NORTH AS SOUTH DAKOTA ACROSS WESTERN NEBRASKA. AT
THE SURFACE...A LARGE AREA OF HIGH PRESSURE HAS LAGGED ACROSS THE
CENTRAL CONUS STRETCHING FROM CANADA TO TEXAS...WHILE WEAK LOW
PRESSURE HAS BEGUN TO DEVELOP ACROSS THE FRONT RANGE.

BEGINNING THE SHORT TERM...THE PLAINS REMAIN UNDER THE INFLUENCE OF
THE INCOMING RIDGE AND ASSOCIATED SURFACE HIGH. THIS HIGH PRESSURE
SYSTEM WILL BEGIN TO SHIFT EASTWARD AS THE MAIN FOCUS OF THE SHORT
TERM SHIFTS TO THE INCOMING SURFACE LOW/TROUGH.

A FEW CONCERNS DURING THE OVERNIGHT PERIOD WILL BE THE INCREASE IN
THE LOW LEVEL JET OVERNIGHT. MODELS INCREASE 850 MB WINDS TO NEAR 40
KTS OVERNIGHT...WITH THE GFS AND THE ECMWF JET LOCATIONS ACROSS THE
WESTERN HALF OF THE STATE AND THE NAM A BIT FURTHER EAST. BOTH THE
NAM AND THE GFS SOLUTION GENERATE SOME POPS WITH THE LOW LEVEL
JET...HOWEVER...THE NAM MODEL REMAINS FURTHER WEST...WHILE THE GFS
GENERATES POPS ACROSS THE FORECAST AREA. THE 4 KM WRF MODEL DOES NOT
PICK UP ON ANY SUGGESTION OF POTENTIAL POPS DURING THE OVERNIGHT
PERIOD. DECIDED TO LEAVE THE OVERNIGHT PERIOD DRY...BUT THIS COULD
BE A CONCERN GIVEN THE LOW LEVEL JET AXIS.

LEADING TOWARDS THE DAYTIME HOURS ON TUESDAY...THE SURFACE TROUGH WILL
CONTINUE TO PUSH EASTWARD...HELPING TIGHTEN THE PRESSURE GRADIENT
ACROSS THE PLAINS. AS A RESULT...INCREASED SOUTH WINDS WILL BE
PREVALENT DURING THE LATE MORNING AND AFTERNOON HOURS ON TUESDAY.
MODELS TRENDS HAVE REMAINED FAIRLY CONSISTENT BETWEEN
RUNS...ALTHOUGH MODEL GUIDANCE AS BEEN TRENDING DOWN SINCE
PREVIOUS RUNS. GIVEN THAT MODELS AND GUIDANCE REMAIN ONLY MARGINAL
WIND ADVISORY AT BEST IN ONLY A FEW LOCATIONS...DECIDED TO OPT OUT
OF ISSUING A WIND ADVISORY AT THIS POINT.

REGARDING TEMPERATURES ON TUESDAY...AS THE UPPER LEVEL RIDGE BUILDS
ACROSS THE PLAINS AND BOUNDARY LAYER MIXING IS EXPECTED TO AT LEAST
850 MB IF NOT 800 MB...SEE NO REASON WHY WE CANNOT TAP INTO SOME
WARM TEMPERATURES. THE NAM AND THE ECMWF REMAIN IN GOOD AGREEMENT
WITH A TEMPERATURE GRADIENT FROM POSSIBLY THE LOW 90S OUT WEST TO
LOW 80S IN THE EAST...THUS SUGGESTING A GRADIENT OF ABOUT 7 TO 10
DEGREES. THE GFS SOLUTION REMAINS THE OUTLIER WITH A MUCH COOLER
GRADIENT WITH MID 80S OUT WEST AND MID 70S EAST. DECIDED TO LEAN
MORE WITH THE NAM/EC SOLUTION ALTHOUGH PORTIONS FARTHER WEST COULD
BE A BIT WARMER AND PORTIONS FARTHER EAST COULD BE A BIT COOLER THAN
FORECAST.

LONG TERM...00Z WED THROUGH MONDAY.  OFF AND ON CHANCES FOR
PRECIPITATION DURING THE EXTENDED WILL BE MAIN CONCERN AS PATTERN
BECOMES MORE ACTIVE.

WEAK MID LEVEL RIDGE SHOULD BEGIN TO SLIDE TO OUR EAST OVERNIGHT
TUESDAY AND LOW AMPLITUDE TROUGH BEGINS TO PUSH INTO THE NW U.S.
FIRST WAVE OF ENERGY WILL KICK OUT AND PUSH A COLD FRONT INTO THE
CENTRAL PLAINS DURING THE DAYTIME ON WED. SHOULD BE ENTERING THE NW
PART OF THE CWA BY SUNRISE WED AND PUSH THROUGH DURING THE DAY. NAM
MORE PROGRESSIVE THAN THE GFS WITH THIS FRONT. ALL MODELS SHOWING
DECENT CAP OVER THE SE HALF OF THE CWA DURING THE AFTERNOON AND
BANKING ON THIS FEATURE TO KEEP THUNDERSTORMS AT BAY DURING THE DAY.
CHANCES INCREASE ESPECIALLY IN THE NORTHERN PART OF THE CWA WED
EVENING AND OVERNIGHT AS MID LEVEL WAVE ROTATES THROUGH HELPING COOL
OFF MID LEVEL TEMPS ESPECIALLY IN THE NORTH. GFS AND OLD EC MODELS
DO SHOW THE BETTER JET SUPPORT TO BE JUST A LITTLE NORTH OF US WITH
RIGHT ENTRANCE AND LEFT EXIT REGIONS OF COUPLED JET FAVORING NW NEB.
MODELS ALSO SHOWING BEST MID LEVEL FRONTOGENESIS IN THIS AREA. WILL
WAIT TO GET A LOOK AT THE 12Z EC RUN BUT UNLESS IT SHOWS SOMETHING
DIFFERENT WILL KEEP WITH PREVIOUS THINKING OF BEST CHANCES FOR
THUNDERSTORMS IN THE NORTHWEST CWA AND DRY IN OUR FAR SOUTHEAST AS
CAP EXPECTED TO HOLD AND EVEN STRENGTHEN IN THAT AREA OVERNIGHT. IN
REGARDS TO SEVERE POTENTIAL...DEEP LAYER SHEAR AND MU CAPE WOULD
SUPPORT SOME SEVERE IN THE AREA.

THURSDAY/THUR NIGHT NOT REAL CLEAR CUT AS MODELS DIFFERING ON PRECIP
CHANCES. INITIAL THOUGHT IS THAT WE WON`T SEE MUCH DURING THE DAY
AND THEN CHANCES INCREASE SOME OVERNIGHT AS LOW LEVEL INCREASES.
HOWEVER WILL LEAVE AT LEAST A SMALL CHANCE IN THE NORTH DURING THE
DAYTIME.  AS FIRST WAVE EJECTS TO OUR NORTH...ANOTHER DEEPER MID
LEVEL LOW PRESSURE SYSTEM IS PROGGED TO DIG FROM THE PACIFIC NW ON
THURSDAY INTO SOUTHERN NEVADA BY SATURDAY BEFORE LIFTING NORTH INTO
SOUTHERN MANITOBA BY MONDAY NIGHT.  THIS TRACK IS MAINLY BASED OFF
THE EC AND IF IT HOLDS TRUE...WE SHOULD BE DRY DURING THE DAYTIME ON
FRIDAY WITH SHORT WAVE RIDGING. STILL LINGERING CHANCES FOR RAIN
FRIDAY NIGHT INTO SATURDAY NIGHT WITH WARM FRONT LIFTING NORTH AND
CYCLONIC FLOW IN THE UPPER LEVELS. SUNDAY COULD BE INTERESTING AS
COLD FRONT SWEEPS THROUGH DURING THE AFTERNOON. EARLY LOOK AT CAPE
AND SHEAR WOULD POINT TO SEVERE WEATHER CHANCE BUT AS USUAL THAT
WILL DEPEND ON TIMING OF A SYSTEM WHICH IS STILL SEVERAL DAYS AWAY.

AS FAR AS HIGH TEMPERATURES GO...WE WILL SEE SOME VARIATION AS
FRONTAL BOUNDARIES PUSH THROUGH...WITH THINGS A LITTLE COOLER ON
WED IN THE NORTH CWA AND THEN OVER THE ENTIRE AREA THURS AND FRI
BEFORE IT WARMS UP AGAIN ON SAT INTO SUNDAY AHEAD OF NEXT COLD
FRONT. NEXT MONDAY SHOULD ONCE AGAIN BE A LITTLE COOLER BEHIND THE
FRONT.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

1148 UPDATE...BRYANT
AVIATION/1021 UPDATE...HEINLEIN
SHORT TERM...SALTZMAN
LONG TERM...EWALD





AREA FORECAST DISCUSSION

NWS WILMINGTON NC

 139 AM EDT TUE MAY 22 2012

.SYNOPSIS...
ALBERTO WILL ACCELERATE OUT TO THE NORTHEAST THROUGH TUESDAY...
MOVING FARTHER AWAY FROM THE U.S. MAINLAND. A WEAK COLD FRONT WILL
SNAKE TO THE EAST AND STALL NEAR OR WEST OF THE FORECAST AREA
TUESDAY NIGHT AND SLOWLY DISSIPATE WEDNESDAY OR THURSDAY. HIGH
PRESSURE WILL EVOLVE ACROSS THE WESTERN ATLANTIC LATE IN THE WEEK
AND RIDGE ACROSS THE REGION THROUGH THE WEEKEND...BRINGING SUMMER
LIKE CONDITIONS.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 1010 PM MONDAY...THE DIURNALLY DRIVEN ISOLATED CONVECTION THIS
EVENING IS NEARLY OVERWITH...AND SHOULD BE A MEMORY BY LATE THIS
EVENING AS THE SEA BREEZE BOUNDARY HAVING TRACKED WELL INLAND...
LOSES ITS LIFTING CAPABILITIES. THIS WILL LEAVE A MOSTLY CLEAR SKY
FOR THE OVERNIGHT...WITH SOME INCREASE OF MOISTURE WEST OF THE I-95
CORRIDOR TOWARDS TUESDAY DAYBREAK. HAVE KEPT POPS NULL AND VOID FROM
LATE THIS EVENING UNTIL THE START OF THE SHORT TERM WHEN LIFT AHEAD
OF THE COLD FRONT BECOMES APPARENT. AS FOR MIN TEMPS...SLIGHT
ADJUSTMENTS MAY BE NEEDED UPWARD TO ACCOUNT FOR THE WIDESPREAD LOW
TO MID 60S DEWPOINTS OVERNIGHT. PATCHY TO AREAS OF FOG WILL BE
POSSIBLE GIVEN THE DECENT RAD CONDITIONS...DECOUPLING OF THE
WINDS...AND AVAILABLE LOW LEVEL MOISTURE.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY...UNSETTLED WEATHER THROUGH THE PERIOD AS AN UPPER
TROUGH DROPS IN FROM THE NORTHWEST TUE THEN BECOMES SEMI-CUTOFF OVER
THE AREA WED. LOOKS LIKE BOTH TUE AND WED WILL BE ACTIVE AS FAR AS
CONVECTION IS CONCERNED. HIGH WILL BE SIMILAR BOTH DAYS...LOW TO MID
80S...WITH DEWPOINT IN THE LOW TO MID 60S. UPPER TROUGH/LOW AND
ASSOCIATED COLD AIR ALOFT COMBINED WITH DIURNAL HEATING...60 DEGREE
DEWPOINTS...CONVERGENCE ALONG THE SEABREEZE WILL PRODUCE CONVECTION
EACH DAY. COVERAGE WISE WED HAD LOOKED A LITTLE MORE FAVORABLE BUT
LATEST GUIDANCE HAS BACKED OFF A BIT ON THE DEEPER MOISTURE. NOW
BOTH DAYS APPEAR SIMILAR WITH RESPECT TO BOTH PRECIP COVERAGE AND
INTENSITY...CARRYING 40-50 POP BOTH DAYS. SBCAPE VALUES ARE IN THE
1000-1500 J/KG RANGE WITH VERTICAL PROFILES SUGGESTING A FEW STRONG
TO POTENTIALLY SEVERE PULSE STORMS COULD DEVELOP. SPC MAINTAINS THE
SEE TEXT FOR TUE AND WITH A SIMILAR ENVIRONMENT EXPECTED ON WED
WOULD NOT BE SHOCKED IF A SEE TEXT WERE ISSUED FOR WED AT SOME
POINT...ESPECIALLY WITH THE COLDEST CORE ALOFT DIRECTLY
OVERHEAD...THOUGH IT WILL BE MODIFYING. PREVIOUS FORECAST CARRIED
CHANCE POP FOR TUE NIGHT...AND GIVEN THE UPPER TROUGH/LOW OVERHEAD
WOULD EXPECT CONVECTION TO CONTINUE INTO THE EARLY MORNING HOURS.
WED NIGHT THINGS START TO DRY OUT AS THE UPPER LOW LIFTS NORTH AND
DRIER AIR STARTS TO INFILTRATE FROM THE SOUTHWEST. OVERNIGHT LOWS
WILL RUN IN THE LOW TO MID 60S.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...THE SOUTHERLY RETURN FLOW INITIALLY AROUND
BERMUDA HIGH WILL BE REPLACED BY A NORTHEAST FLOW AS HIGH PRESSURE
RIDGES DOWN FROM CANADA BY SAT. OVERALL THE SURFACE FLOW WILL BE
DOMINATED MORE BY LAND/SEA BREEZE THROUGH MOST OF THE LONG TERM AS
PRESSURE PATTERN REMAINS WEAK. EXPECT DEEP S-SW FLOW RETURN FLOW ON
THURS AS MID TO UPPER TROUGH CONTINUES TO DIG DOWN TO OUR WEST AND
BERMUDA HIGH RIDGES IN FROM THE ATLANTIC. THE H5 TROUGH AXIS SHOULD
MOVE OFF SHORE THURS NIGHT WITH A DEEPER NE FLOW DEVELOPING AS UPPER
RIDGE BUILDS INTO THE CAROLINAS FROM THE WEST THROUGH THE WEEKEND.
ENERGY FROM THIS H5 SHORTWAVE MAY PROVIDE SOME ENHANCEMENT TO
LOCALIZED CONVECTION THURS AFTERNOON BUT WE WILL ACTUALLY GET SOME
DRIER AIR MOVING IN FROM THE SW IN THE MID LEVELS COMING AROUND THE
BASE OF THE TROUGH ON THURS. THIS SHOULD HELP TO INHIBIT ANY STRONG
CONVECTION BUT WILL KEEP ISOLATED SHWRS IN THE FORECAST MAINLY LATE
DAY THURS INTO THURS NIGHT BEFORE SHORTWAVE LIFTS OFF TO THE
NORTHEAST. EXPECT PLENTY OF SUBSIDENCE ON BACK END OF TROUGH AS
RIDGE BUILDS IN LATE FRI THROUGH THE WEEKEND. HEIGHTS INCREASE CLOSE
TO 590 DEM OVER THE WEEKEND AS RIDGE BUILDS TO OUR WEST. OVERALL
EXPECT ONLY LOCALIZED CONVECTION POSSIBLE ALONG SEA BREEZE WITH A
SUMMER-LIKE AIR MASS IN PLACE. DEWPOINTS WILL BE IN THE MID 60S
THROUGH THE WEEKEND. A WAVE OF LOW PRESSURE MAY MOVE INTO THE
CAROLINAS SUN NIGHT INTO MONDAY WHICH MAY PRODUCE A BETTER CHC OF
PCP TOWARD THE END OF THE MEMORIAL DAY WEEKEND WITH A STRONGER ON
SHORE FLOW.

TEMPS SHOULD RUN ABOVE NORMAL THROUGH THE EXTENDED PERIOD AS RIDGE
BUILDS AND HEIGHTS RISE. EXPECT LESS OF A DIURNAL TREND AS A MORE
HUMID AIR MASS WILL REMAIN IN PLACE. OVERALL 80S DURING THE DAY AND
60S AT NIGHT. TEMPS SHOULD BE HIGHEST ON SUNDAY AS HEIGHTS PEAK OVER
LOCAL AREA NEAR 590 DEM.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 06Z...EXPECT VFR THROUGH THE EARLY OVERNIGHT HOURS...WITH
PATCHY DENSE FOG CREATING MVFR/POTENTIAL IFR LATE OVERNIGHT INTO THE
EARLY MORNING HOURS. VFR WILL PREVAIL BY MORNING...WITH POTENTIAL
FOR BRIEF MVFR IN AFTERNOON VCSH.

FEW/SCT MID TO HIGH LEVEL CLOUDS WILL LINGER THROUGH THE OVERNIGHT
HOURS...WITH LIGHT AND VARIABLE WINDS. GIVEN AVAILABLE LOW LEVEL
MOISTURE...LIGHT WINDS AND SOMEWHAT MODERATE RADIATIONAL COOLING
CONDITIONS...EXPECT PATCHY DENSE FOG LATE OVERNIGHT INTO THE EARLY
MORNING HOURS. FOR NOW HAVE KEPT RESTRICTIONS AT MVFR...BUT CANNOT
RULE OUT VISIBILITIES BEING REDUCED EVEN MORE CREATING IFR
CONDITIONS...ESPECIALLY ALONG THE COAST. AFTER DAYBREAK...ANY
LINGERING FOG WILL QUICKLY BURN OFF AND POSSIBLY WILL SEE SCT
LOWERED CLOUD HEIGHTS. VFR WILL PREVAIL WITH LIGHT WEST WINDS WHICH
WILL GRADUALLY BACK TO THE SOUTH-SOUTHWEST. BY THE AFTERNOON
HOURS...SUSTAINED WINDS WILL BE AOB 12 KTS. FOR LATE MORNING THROUGH
THE END OF THE VALID PERIOD...WILL HAVE CHANCE FOR ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS. FOR NOW HAVE KEPT IN VCSH.
CANNOT RULE OUT BRIEF MVFR IN HEAVIER DOWNPOURS. AFTER
SUNSET...WINDS WILL BECOME LIGHT WITH BKN CLOUD COVER.

EXTENDED OUTLOOK...SCATTERED SHOWERS CREATING MVFR...WITH ISOLATED
THUNDERSTORMS CREATING TEMPO IFR POSSIBLE THROUGH THE EXTENDED
PERIOD.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1010 PM MONDAY...ALBERTO IS ON THE MOVE...BUT FORTUNATELY
TOWARD THE EAST NORTHEAST TAKING IT WELL OFFSHORE FROM THE SOUTHEAST
U.S. COAST TONIGHT THROUGH TUESDAY. THE LATEST HRRR HAS FINALLY
CAUGHT UP WITH THE GENERAL CONSENSUS OF PUSHING IT FURTHER AWAY FROM
THE MAINLAND. LOOK FOR VEERING WIND DIRECTIONS OVERNIGHT FROM NE-E
TO W-NW BY DAYBREAK TUESDAY. WIND SPEEDS...5 TO 10 KT.

SIGNIFICANT SEAS WILL RUN AROUND 3 FT THIS EVENING. WAVEWATCH3 AND
SWAN INDICATE AN ESE 4 TO 5 FT WAVE TRAIN WITH PERIODS 9-10 SECONDS
WILL AFFECT THE ILM WATERS DURING THE PRE-DAWN HOURS OF TUESDAY AND
THERE-AFTER. WILL INDICATE CURRENT SIGNIFICANT SEAS OF 2 TO 3 FT...
BUILDING TO 3 TO 4 FT OVERNIGHT INTO TUESDAY. THE OUTER WATERS FROM
CAPE FEAR NORTHWARD COULD OBSERVE 5 FOOTERS FROM THIS TRAIN.
THE SHADOW CREATED BY FPS WITH AN EASTERLY SWELL...WILL KEEP SEAS
CLOSER TO 2 FT ACROSS THE WATERS OFF BRUNSWICK COUNTY.

SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 2 PM MONDAY...SOUTH TO SOUTHWEST FLOW WILL DOMINATE THE
PERIOD. SWELL FROM ALBERTO WILL AFFECT THE WATERS TUE INTO WED.
WIND SPEEDS WILL BE 10 TO 15 KT FOR THE MAJORITY OF THE PERIOD...
SLIGHTLY LESS AT NIGHT...WITH SOME NEAR SHORE ENHANCEMENT EACH DAY
AS THE SEABREEZE DEVELOPS. SEAS WILL BE A COMBINATION OF SOUTHERLY
WIND WAVE AND SOUTHEAST TO EAST ALBERTO SWELL...RUNNING 3 TO 4 FT
BOTH TUE AND WED.

LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 3 PM MONDAY...SOUTHERLY RETURN FLOW ON THURS AROUND BERMUDA
HIGH WILL BE REPLACED BY A N-NE FLOW THROUGH LATE FRI AS HIGH
PRESSURE BUILDS DOWN FROM CANADA. WINDS NEAR SHORE WILL BE DRIVEN
BY LAND/SEA BREEZE AS OVERALL PRESSURE PATTERN REMAINS MORE ON THE
WEAK SIDE. WINDS GENERALLY LESS THAN 15 KTS THURS AND FRI MAY
INCREASE THROUGH THE LATTER HALF OF THE WEEKEND AS A WAVE OF LOW
PRESSURE MOVES WESTWARD FROM THE OFF SHORE ATLANTIC WATERS TOWARD
THE LOCAL WATERS.

SEAS WILL BE REMAIN 2 TO 3 FT THROUGH MOST OF THE PERIOD BUT MAY
INCREASE WITH A STRONG ON SHORE PUSH BY LATE IN THE WEEKEND AS WAVE
OF LOW PRESSURE MIGRATES WESTWARD TOWARD LOCAL WATERS. SEAS WILL MIX
WITH A DECREASING EASTERLY SWELL AROUND 9 SECONDS ON THURS.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...DCH
SHORT TERM...III
LONG TERM...RGZ
AVIATION...SGL/RJD






AREA FORECAST DISCUSSION

NWS CLEVELAND OH

 1241 AM EDT TUE MAY 22 2012

.SYNOPSIS...
A COLD FRONT WILL MOVE OUT OF THE AREA THIS EVENING. HIGH
PRESSURE WILL GRADUALLY BUILD EAST OVER THE REGION BY WEDNESDAY
MORNING. THE HIGH PRESSURE CENTER WILL MOVE TO THE EAST COAST BY
WEDNESDAY NIGHT ALLOWING A WARM FRONT TO LIFT NORTH ACROSS THE
AREA THURSDAY. A WEAK COLD FRONT WILL APPROACH THE AREA LATE FRIDAY.

&&

.NEAR TERM /THROUGH TODAY/...
EXCEPT FOR A CLUSTER OF CONVECTION CENTERED IN WAYNE CO...MUCH OF
THE DAYTIME CONVECTION HAD DISSIPATED. A BAND OF SHRA IN THE COOLER
AIR OVER THE WESTERN PART OF THE AREA ASSOCIATED WITH THE UPPER
TROUGH IS TRYING TO GET GOING BUT WILL HAVE A HARD TIME DUE TO A
MORE STABLE AIRMASS IN THAT AREA. WILL KEEP SMALL CHANCE GOING FOR
MOST AREAS THROUGH MIDNIGHT THEN BEGIN TO SHIFT CHANCE INTO THE
SOUTHEAST HALF OF THE AREA OVER THE COURSE OF THE REST OF THE NIGHT.
RUC AND HRRR DISAGREE SO OVERALL CONFIDENCE LOW FOR THE REST OF THE
NIGHT BUT DO FEEL ANY NEW ACTIVITY WILL BE LIGHT.

REST OF FORECAST SEEMS TO BE ON TRACK SO LITTLE WILL BE CHANGED.

&&

.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
THE FRONT WILL
BE JUST TO THE EAST OF THE FORECAST AREA. WITH A FAIR AMOUNT OF
MOISTURE...WILL CONTINUE WITH CHANCE POPS INTO THE
AFTERNOON...MAINLY IN THE EAST...WITH DECREASING CLOUDS ELSEWHERE.
OTHERWISE HIGH PRESSURE BUILDING IN TUESDAY NIGHT AND THE HIGH WILL
WEAKEN WEDNESDAY NIGHT. A WARM FRONT WILL MOVE ACROSS THE AREA
THURSDAY. ON THE EDGE ABOUT THE THREAT OF PRECIPITATION...ANY QPF
WOULD BE VERY LIGHT. JUST WENT WITH 20 POPS AT THE MOMENT AND WILL
MONITOR IT CLOSELY.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
BEGINNING FRIDAY IN THE LONG TERM GFS AND ECMWF SHOWING COLD FRONT
APPROACHING THE AREA BUT LOOKS LIKE TEMPS WILL BE QUITE ABOVE NORMAL
WITH SHOWERS AND THUNDERSTORMS HOLDING OFF MOVING INTO WESTERN AREAS
UNTIL LATE DAY/EVENING...WITH BETTER CHANCES ACROSS THE NORTHERN
HALF OF THE AREA FRIDAY NIGHT. THE PATTERN LOOKS TO BE TRICKY GOING
INTO THE WEEKEND HOWEVER WITH BOTH MODELS SHOWING THE FRONTAL
BOUNDARY ORIENTING ITSELF MORE WEST TO EAST ACROSS THE AREA ON
SATURDAY. WITH THE BOUNDARY ACROSS THE AREA THE CHANCES FOR SHOWERS
AND THUNDERSTORMS WILL CONTINUE. HOWEVER...GIVEN THIS FAR OUT IN THE
EXTENDED MAINLY WENT WITH LOW CHC TO SLGT CHC POPS ON SATURDAY.
THERE IS SOME DISCREPANCY WITH HOW STRONG HIGH PRESSURE TO THE NORTH
MAY RIDGE INTO THE AREA ON SUNDAY PUSHING THE FRONT FURTHER SOUTH
AWAY FROM THE AREA...BUT FOR NOW LEANED TOWARD DRIER CONDITIONS
GIVEN LOW CONFIDENCE ON TIMING OF ANY PRECIP. GIVEN MODEL
DIFFERENCES IN THE LONG TERM LEANED MORE TOWARD PREVIOUS FORECAST
TEMPS OVER SAT AND SUN GIVEN MODEL DIFFERENCES.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
EXPECTING GRADUALLY IMPROVING CONDITIONS FROM WEST TO EAST DURING
THE DAY AS COLD FRONT CONTINUES TO MOVE WELL EAST OF THE AREA.
HIGH PRESSURE WILL BUILD EAST INTO THE REGION LATER TONIGHT INTO
WEDNESDAY. EXPECTING VFR CONDITIONS THROUGH THE LATTER HALF OF THE
TAF PERIOD. WINDS ARE EXPECTED TO CONTINUE OUT OF AROUND 350
DEGREES AT 10 TO 15 KNOTS THROUGH THE OVERNIGHT HOURS AND BEGIN TO
DIMINISH AFTER SUNRISE. LIGHT WINDS ALREADY BEING REPORTED JUST TO
THE WEST AND EXPECT THIS TO GET INTO OUR AREA TODAY.

.OUTLOOK...NON-VFR POSSIBLE IN EARLY MORNING FOG/HAZE WEDNESDAY.

&&

.MARINE...
QUICK UPDATE NEEDED TO COVER GUSTY WINDS ON THE LAKE. BUOY 45005
WAS REPORTING 20 KNOT WINDS WITH 4 FOOT WAVES. DECIDED TO HOIST
SMALL CRAFT ADVISORY FROM CONNEAUT ALL THE WAY TO THE ISLANDS TO
COVER THE HIGHER WAVE AND WIND SITUATION. SMALL CRAFT ADVISORY UP
UNTIL NOON.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT TODAY FOR LEZ142>148.

&&

$$
SYNOPSIS...KIELTYKA
NEAR TERM...KIELTYKA
SHORT TERM...KIELTYKA
LONG TERM...ABE
AVIATION...LOMBARDY
MARINE...LOMBARDY







AREA FORECAST DISCUSSION

NWS NORMAN OK

 418 AM CDT TUE MAY 22 2012

.DISCUSSION...
MID-LEVEL NORTHWEST TO WEST FLOW WILL GRADUALLY TRANSITION
TO A SOUTHWEST FLOW OVER THE NEXT 48 HOURS AS A BROAD
TROUGH TAKES SHAPE OVER THE WESTERN HALF OF THE CONUS.
MEANWHILE...CONVECTION ACROSS TEXAS PANHANDLE HAS WEAKENED
OVERNIGHT WITH MCV-LIKE FEATURE IN WEAK ECHO RETURNS.
TO THE EAST...ISOLATED SHOWERS HAVE BEEN FORMING ACROSS
THE WESTERN THIRD OF OKLAHOMA FROM HARPER COUNTY TO
KIOWA. NAM12 AND RECENT HRRR RUNS ARE MORE BULLISH
WITH THE DEVELOPMENT OF MORE SHOWERS/STORMS BETWEEN
10-15Z ACROSS WESTERN HALF OF FA. WITH RECENT
DEVELOPMENT WILL ADD 20-30 POPS ACROSS WESTERN 1/3 OF
FA. PRECIP THAT DOES DEVELOP SHOULD GRADUALLY WEAKEN
DURING THE MID TO LATE MORNING.

AFTERNOON CONVECTION MAY DEVELOP WEST OF THE AREA BUT
OVERALL COVERAGE MAY LIMIT CHANCES OF IMPACTING WESTERN
OKLAHOMA..SO WILL KEEP POPS RATHER LOW.

SOUTH WINDS WILL INCREASE SOME TODAY AND WILL BECOME RATHER
GUSTY ON WEDNESDAY AS LOW PRESSURE DEEPENS OVER THE
HIGHER TERRAIN.

A SHORTWAVE WILL MOVE FROM THE CENTRAL ROCKIES INTO THE
UPPER MIDWEST LATE WEDNESDAY INTO THURSDAY. THIS FEATURE
WILL HELP PUSH A WEAK SURFACE BOUNDARY INTO NORTHWEST
AND WEST CENTRAL OKLAHOMA WEDNESDAY NIGHT/EARLY THURSDAY.
RATHER WARM 8H TEMPS AND BETTER FORCING NORTH...SHOULD LIMIT
STORM CHANCES WITH THIS BOUNDARY.

AN UPPER RIDGE WILL BUILD OVER THE SOUTHEAST GOING INTO THE
HOLIDAY WEEKEND...WHILE ANOTHER STORM SYSTEM MOVES ACROSS
THE WESTERN THIRD OF THE US.  EC MODEL STRONGER WITH WESTERN
SYSTEM AND MAY BRING A CHANCE OF STORMS TO WESTERN OKLAHOMA
BY SUNDAY...AS IT LIFTS NORTH INTO THE NORTHERN ROCKIES AND
PLAINS. OVERALL...THE HOLIDAY WEEKEND APPEARS MAINLY DRY AND VERY
WARM/HOT WITH BETTER CHANCES FOR STORMS ACROSS WESTERN OK. MODELS
SIGNAL A RETURN TO A NORTHWEST FLOW BY THE MIDDLE OF NEXT WEEK
WHICH MAY BRING BETTER CHANCES FOR STORMS DURING THE LAST DAYS OF
MAY.


&&

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK  85  65  90  67 /  10  10  10  10
HOBART OK         89  64  95  68 /  30  10  10  10
WICHITA FALLS TX  92  66  97  68 /  30  10  10  10
GAGE OK           89  62  93  62 /  20  10  10  10
PONCA CITY OK     83  65  90  68 /  10  10  10  10
DURANT OK         88  65  93  65 /  10  10   0  10

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&

$$




AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

 455 AM EDT TUE MAY 22 2012

.SYNOPSIS...
A LARGE SCALE TROUGH OF LOW PRESSURE WILL REMAIN IN PLACE ACROSS
THE EASTERN U.S. THROUGH THURSDAY...BRINGING SEVERAL ROUNDS OF
SHOWERS AND A FEW THUNDERSTORMS. A SOUTHWEST FLOW OF WARMER AND
HUMID AIR WILL FOLLOW FOR FRIDAY...AND THE ABOVE NORMAL TEMPERATURES
WILL CONTINUE THROUGH THE UPCOMING WEEKEND. A WEAK COLD FRONT WILL
ATTEMPT TO PUSH SOUTHEAST THROUGH THE REGION SATURDAY AFTERNOON AND
EVENING...BUT COULD STALL OUT ACROSS OR JUST TO THE NORTH OF THE
REGION.

&&

.NEAR TERM /THROUGH TONIGHT/...
MOST OF THE EARLIER MDT TO HVY SHRA HAVE DISSIPATED ACROSS THE
CWA...WITH THE EXCEPTION OF THE NCENT MTNS WHERE A SMALL AREA OF
SHOWERS WAS DRIFTING SLOWLY TO THE NORTH.

NEARLY NORTH/SOUTH AXIS OF BOUNDARY LAYER THETA-E CONVERGENCE
EXTENDED FROM NCENT PENN...TO THE SCENT MTNS AND LAUREL HIGHLANDS
EARLY TODAY. 06Z RUC INDICATES THAT THIS AXIS WILL SHIFT A FEW
LAYERS OF COUNTIES TO THE WEST BY THIS AFTERNOON...WHILE A NOTABLE
AREA OF LLVL MOISTURE DIVERGENCE WILL DRIFT NE AND BECOME LOCATED
ACROSS THE SUSQ VALLEY DURING THE MID AFTERNOON HOURS.

THE MOST NUMEROUS SHOWERS AND THUNDERSTORMS WILL BE CONFINED TO
THE WESTERN HALF OF THE CWA INTO THE LATE AFTERNOON. THE APPROACH
OF A AN 850 MB TROUGH AND RIBBON OF SLIGHTLY STEEPER MID LEVEL
LAPSE RATES LATE THIS AFTERNOON AND TONIGHT WILL HELP TO SHIFT THE
AXIS OF MOST NUMEROUS SHOWERS AND SCTD TSRA TO THE SUSQ VALLEY
POINTS EAST FOR VERY LATE TODAY...INTO EARLY WED MORNING.

THE SLOW MOVEMENT OF THE SHOWERS AND STORMS TODAY /AND PERSISTENT
FOCUS AREA/ COULD LEAD TO SOME MODERATELY HEAVY ADDITIONAL RAINFALL
OF 0.5 TO 1.0 OF AN INCH. LESSER AMOUNTS OF RAIN ARE EXPECTED FOR
THE FAR NW CORNER OF THE CWA...AND ALSO FROM THE SUSQ VALLEY...EAST.
OVERCAST SKIES AND VERY LGT WINDS ALOFT SUGGEST THERE WILL BE VERY
LITTLE THREAT OF SVR WX.

&&

.SHORT TERM /WEDNESDAY/...
THE MEAN LARGE-SCALE TROUGH AT THE SFC AND ALOFT WILL CONTINUE TO
RESIDE RIGHT ALONG THE APPALACHIAN MTN CHAIN THROUGH AT LEAST
WEDNESDAY NIGHT...AS THE DEVELOPING UPPER LOW ACROSS THE TENN VALLEY
LIFTS SLOWLY NE ACROSS THE VIRGINIAS AND PENN. THE PRIMARY AXIS OF
LLVL PWATS AND ASSOCIATED THETA-E CONVERGENCE SHOULD SHIFT SLIGHTLY
TO THE EAST ON WEDNESDAY /BECOMING LOCATED FROM THE UPPER SUSQ
VALLEY...TO THE SCENT MTNS AND LAURELS/...ALONG AND JUST TO THE EAST
OF THE WEAKENING UPPER LOW TRACK.

INSTABILITY RAMPS UP A FEW HUNDRED J/KG IN THE CAPE DEPT
WEDNESDAY...WITH THE BEST CONVECTIVE POTENTIAL ALONG AND TO THE SE
OF A LINE FROM KIPT TO KAOO. VERY WEAK WINDS IN THE LOWEST 15 KFT OF
THE ATMOSPHERE WILL KEEP THE EHI/S ON THE VERY LOW SIDE...WITH THE
MAIN CHARACTERISTIC OF THE CONVECTION BEING IT/S SLOW MOVEMENT AND
LOCALIZED HEAVY RAIN POTENTIAL. PWATS ARE NOT TREMENDOUSLY HIGH -
ONLY 1-2 STANDARD DEVIATIONS ABOVE NORMAL...AND WITH THE EXTENSIVE
CLOUD COVER...HIGH CAPES OF 2000 J/KG OR MORE WILL BE DIFFICULT TO
COME BY. STILL...THE 00Z GEFS AND 03Z SREF TARGET THE SCENT MTNS AND
MID SUSQ VALLEY FOR ABOUT A 60 PERCENT CHC FOR SFC BASED CAPES TO
EXCEED 1200 J/KG.

BASIN AVG RAINFALL AMOUNTS FOR THE NEXT 36 HOURS WILL BE MAINLY IN
THE 0.5 TO 1.0 RANGE. AREAS RECEIVING A FEW TSRA COULD SEE NEARLY
1.5 INCHES /AS INDICATED BY SEVERAL SREF AND GEFS PLUME MEMBERS/.
&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
A SLOWLY FILLING UPPER LOW WILL DRIFT NE FROM THE CENTRAL
APPALACHIANS AND CROSS SERN PENN ON THURSDAY. WED EVENING
CONVECTION WILL QUICKLY WANE BY 04Z WITH CLOUDY SKIES...LIGHT
WIND AND AREAS OF FOG FOLLOWING FOR THE REST OF THE OVERNIGHT HOURS.
ISOLATED TO SCATTERED...MAINLY AFTERNOON AND EARLY EVENING SHRA
AND TSRA WILL OCCUR THURSDAY AND FRIDAY.

GFS AND OTHERS ARE MORE IN LINE WITH KEEPING FRONT NORTH OF OUR AREA
THIS COMING HOLIDAY WEEKEND...WHILE THE LATEST EC MAKES AN ATTEMPT
TO PUSH THE SHALLOW FRONT TO THE SOUTHERN TIER OF PA SATURDAY NIGHT.
A LARGE POOL OF VERY WARM AIR AT THE SFC AND ALOFT FORMS ACROSS THE
LOWER-MID MISS VALLEY AND OHIO RIVER VALLEY OVER THE UPCOMING
WEEKEND.

THE SOUTHERN EDGE OF WNW FLOW ALOFT /FROM THE GREAT LAKES TO THE
SOUTHERN NEW ENGLAND COAST/ WILL TRANSPORT SOME RIPPLES OF ENERGY
ALOFT ALONG/ABOVE THE LLVL FRONTAL BOUNDARY...POSSIBLY SPARKING SOME
SHOWERS AND TSRA. WE COULD EVEN SEE AN MCS OR TWO TRACK SE INTO THE
WRN AND CENTRAL CWA FROM THE UPPER LAKES REGION SATURDAY MORNING
/AND AGAIN SUNDAY/ WITHIN THE CHANNEL OF PWATS RANGING FROM 32-36MM.
GFS BEST ILLUSTRATES THE POTENTIAL /VIA ITS 500 MB VORT PANELS/ FOR
A FEW RING OF FIRE MCS/S TO SLIDE SE ACROSS MAINLY NRN AND WESTERN
PART OF PENN.

&&

.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
SEMI-PERSISTENT N-S AXIS OF RAIN SPLITTING CWA THIS
MORNING...CONTINUES TO GRADUALLY WEAKEN. OUTSIDE OF THAT...ANY
PRECIP WILL BE ISOLATED AND LIGHT THROUGH THE OVERNIGHT HOURS.
MVFR TO IFR CONDITIONS HAVE SETTLED IN WITH LOWERING CIGS IN VERY
MOIST AIRMASS. EXPECT THESE TO DROP EVEN FURTHER OVERNIGHT...WITH
WIDESPREAD IFR-LIFR LINGERING INTO THE MID MORNING.

SOME DIURNAL IMPROVEMENT IN CONDITIONS ON TUESDAY AS CIGS LIFT TO
MVFR DURING THE MID/LATE MORNING...EVENTUALLY BECOMING VFR IN MANY
PLACES DURING THE AFTERNOON AS UPPER FLOW BECOMES A BIT MORE
SOUTHERLY IN ADVANCE OF NEWLY DEVELOPING TN VALLEY UPPER LEVEL
LOW. WITH THE POTENTIAL INCREASE IN CIGS AND VSBYS WILL BE
INCREASING CHANCES OF SHOWERS AND POSSIBLE TSRA...BRINGING LOCAL
RESTRICTIONS.

OUTLOOK...
WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN SHRA AND SCT
TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSRA POSS MAINLY SE.
FRI...PRIMARILY VFR. ISOLD SHRA/TSRA POSS MAINLY SE.
SAT...VFR. A CHC OF A SHRA OR TSRA ACROSS THE NORTH.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/MARTIN
AVIATION...JUNG/RXR










AREA FORECAST DISCUSSION

NWS SAN ANGELO TX

 1149 PM CDT MON MAY 21 2012


.DISCUSSION...
/SEE BELOW FOR AVIATION DISCUSSION/

&&

.AVIATION...
LARGE COMPLEX OF THUNDERSTORMS MOVING SOUTHEAST AT 20 KTS OUT OF
THE PANHANDLE WILL LIKELY WEAKEN AND DISSIPATE AS IT APPROACHES WEST
CENTRAL TEXAS LATE TONIGHT...ACCORDING TO THE RUC NAM AND GFS
MODELS. HOWEVER IF THE COMPLEX DOES SURVIVE MOVING OFF THE CAPROCK
...IT WOULD STILL TAKE UNTIL AFTER 12Z TO AFFECT KSJT AND KABI.
WILL CONTINUE VFR CONDITIONS IN THE TAFS.

04

&&

.PREV DISCUSSION... /ISSUED 948 PM CDT MON MAY 21 2012/

DISCUSSION...
HAVE UPDATED THE FORECAST TO TAKE OUT THE EARLY MENTION OF
THUNDERSTORMS...AND MAKE SLIGHT ADJUSTMENTS TO THE POPS/WX AFTER
MIDNIGHT TONIGHT. LATEST MODEL GUIDANCE SUGGESTS THE MCS THAT HAS
FORMED NORTHWEST OF LUBBOCK THIS EVENING COULD SURVIVE LONG ENOUGH
TO MAKE IT INTO OUR NORTHWEST COUNTIES AFTER MIDNIGHT TONIGHT...
AND POSSIBLY EVEN RESULT IN ISOLATED SHOWERS/THUNDERSTORMS MAKING
IT TO NEAR THE ABILENE AREA TOWARDS SUNRISE. NO OTHER CHANGES
WERE MADE TO THE FORECAST. UPDATED PRODUCTS WILL BE OUT
SOON...GRIDS HAVE BEEN SENT AND PUBLISHED. 20

PREV DISCUSSION... /ISSUED 611 PM CDT MON MAY 21 2012/

DISCUSSION...
/SEE BELOW FOR AVIATION DISCUSSION/

AVIATION...
ISOLATED SHOWERS POSSIBLE NEAR BRADY AS AN OUTFLOW BOUNDARY MOVES
THROUGH AROUND 1Z...BUT TOO REMOTE TO INCLUDE IN THE KBBD TAF. POTENTIAL
EXISTS FOR A FEW PATCHES OF STRATUS POSSIBLE TOWARD DAYBREAK...MAINLY
ALONG THE I-10 CORRIDOR. HOWEVER MOST AREAS WILL REMAIN VFR AND
WILL KEEP TAFS VFR.

04

PREV DISCUSSION... /ISSUED 311 PM CDT MON MAY 21 2012/

SHORT TERM...
STALLED COLD FRONT IS LOCATED ALONG A LINE FROM NEAR SWEETWATER...TO
JUST NORTH OF ABILENE. TOWERING CUMULUS IS EVIDENT ON VISIBLE
SATELLITE ALONG AND AHEAD OF THE BOUNDARY...OVER THE SOUTHERN BIG
COUNTRY AND NORTHERN CONCHO VALLEY. SHOWERS ARE STRUGGLING TO
DEVELOP THIS AFTERNOON...BUT AS CONTINUED HEATING HELPS TO DECREASE
THE CAP LATER THIS AFTERNOON...ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS MAY DEVELOP ACROSS PARTS OF THE BIG COUNTRY AND CONCHO
VALLEY. EXPECT MOST OF THE ACTIVITY TO QUICKLY DISSIPATE SHORTLY
AFTER SUNSET. THE NEXT MAIN ISSUE IS WHETHER AN MCS WILL DEVELOP
OVER THE SOUTH PLAINS REGION...AND TRY TO MOVE INTO AT LEAST THE
NORTHWEST PORTIONS OF WEST CENTRAL TEXAS EARLY TUESDAY MORNING. FOR
NOW...HAVE SLIGHT CHANCE POPS ACROSS BIG COUNTRY AFTER 06Z...WITH
MOST CONVECTION ENDING BY 12Z.

ON TUESDAY...A SURFACE TROUGH WILL DEVELOP ALONG THE LEE SIDE OF THE
ROCKIES...INCREASING THE SURFACE PRESSURE GRADIENT OVER WEST CENTRAL
TEXAS SLIGHTLY. SOUTH WINDS WILL INCREASE TO 10 TO 15 MPH. 850MB
TEMPERATURES LOOK SLIGHTLY WARMER THAN WHAT IS BEING EXPERIENCED
THIS AFTERNOON...SO FORECAST REFLECTS SLIGHTLY WARMER TEMPERATURES.
HIGHS AROUND THE AREA WILL GENERALLY BE IN THE LOWER 90S.

LONG TERM...
LONGER TERM PORTION OF THE FORECAST APPEARS FAIRLY QUIET OVERALL.
AS A DEEP LONGWAVE TROUGH DEVELOPS OVER THE ROCKIES...THE
NORTHWEST FLOW ALOFT WILL TRANSITION TO SOUTHWEST FLOW BY LATE WEDNESDAY.
DRYLINE WILL DEVELOP AND SLOSH BACK AND FORTH ACROSS THE PERMIAN
BASIN AND INTO THE WESTERN CONCHO VALLEY AND BIG COUNTRY...BUT CAP
STRENGTH LOOKS AWFULLY STRONG THROUGH THE REST OF THE WEEK. WILL
KEEP THE FORECAST DRY FOR NOW. TEMPERATURES AHEAD OF THE DRYLINE
WILL BE AT OR A LITTLE ABOVE NORMAL...BUT STRONGER SOUTHWEST
DOWNSLOPE FLOW BEHIND THE DRYLINE WILL DRIVE TEMPERATURES TO NEAR
THE 100 DEGREE MARK ACROSS THE WESTERN CONCHO VALLEY AND BIG COUNTRY.

BOTH THE GFS AND THE ECMWF INDICATE A STRONGER SHORTWAVE ROTATING
INTO THE SOUTHERN PLAINS FOR SATURDAY AFTERNOON AND EVENING. GIVEN
THIS ADDED BOOST...A FEW STORMS MAY BE POSSIBLE. STILL...HAVE SOME
QUESTIONS ABOUT THE TIMING AND STRENGTH OF THE WAVE...SO WILL HOLD
OFF FOR NOW AND CONTINUE TO MONITOR.

&&

.PRELIMINARY POINT TEMPS/POPS...
ABILENE  64  91  67  95  71 /  20  10  10   0  10
SAN ANGELO  63  92  65  96  70 /  10  10   0   0  10
JUNCTION  61  91  65  92  67 /  10   0   0   0   0

&&

.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

99/99/04







AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 1147 PM CDT MON MAY 21 2012

.SHORT TERM...TONIGHT THROUGH THURSDAY
325 PM CDT MON MAY 21 2012

MAIN FORECAST CONCERNS ARE FROST POTENTIAL TONIGHT AND PRECIPITATION
CHANCES AS WELL AS TEMPERATURES WEDNESDAY INTO THURSDAY.

CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED RIDGING FROM THE DESERT SOUTHWEST INTO ALBERTA AND WEAK
TROUGHING OVER THE WESTERN GREAT LAKES REGION. HIGH PRESSURE
DOMINATES AT THE SURFACE ON THE BACK SIDE OF THE WEAK TROUGHING...
ENCOMPASSING THE ENTIRE FORECAST AREA. DRY AIR...SEEN ON THE 12Z
MPX...GRB AND DVN SOUNDINGS HAS RESULTED IN A SUNNY DAY ACROSS THE
FORECAST AREA. MIXING UP THROUGH 850MB WHERE TEMPS ARE AROUND 6C HAS
YIELDED TEMPERATURES MAINLY IN THE 70S...AND DEWPOINTS MOSTLY DOWN
INTO THE LOW TO MID 30S. TO THE WEST...AN AREA OF MID LEVEL CLOUDS
HAVE BEEN EXPANDING ACROSS NORTH DAKOTA AND INTO WESTERN MINNESOTA.
THESE CLOUDS ARE IN RESPONSE TO WARM ADVECTION AND MOISTURE RETURN
ON THE BACK SIDE OF THE SURFACE HIGH AND AHEAD OF THE UPPER RIDGE
AXIS. THERE WAS A LITTLE LIGHT SHOWER ACTIVITY ON THE WESTERN SIDE
OF THE CLOUDS...ASSOCIATED WITH 305 K ISENTROPIC LIFT...BUT THIS HAS
SINCE DISSIPATED. 12Z SOUNDINGS SHOWED MUCH WARMER AIR OVER THE
DAKOTAS...WITH 850MB TEMPS OF 10-15C ON AVERAGE WITH RAPID CITY AT
19C.

TONIGHT AND TUESDAY...UPPER RIDGING OVER THE NORTHERN ROCKIES WILL
SHIFT EAST INTO THE FORECAST AREA ON TUESDAY...PUSHED ALONG BY
TROUGHING CURRENTLY OFF THE PACIFIC NORTHWEST MOVING INLAND. IN
RESPONSE...A SURFACE LOW DEEPENS ACROSS THE DAKOTAS...INCREASING THE
WARM ADVECTION DOWNSTREAM INTO THE FORECAST AREA. WITH THIS WARM
ADVECTION WE SHOULD SEE SOME OF THOSE MID CLOUDS OVER WESTERN
MINNESOTA MOVE ACROSS. TRENDS IN MODEL RH FIELDS SUGGEST SOME
DISSIPATION OF THE MID CLOUDS AS THEY PUSH EAST...ESPECIALLY DURING
THE DAY TUESDAY. THIS MATCHES THE PREVIOUS FORECAST. IN ADDITION...
IT APPEARS MOST OF THE MID CLOUDS WILL STAY WEST OF THE MISSISSIPPI
RIVER TONIGHT. THIS IS CRITICAL BECAUSE THE SURFACE RIDGE SHOULD BE
CENTERED OVER WISCONSIN MUCH OF TONIGHT...LEADING TO FAVORABLE
RADIATIONAL COOLING CONDITIONS. SINCE BLACK RIVER FALLS AND SPARTA
DROPPED INTO THE LOW TO MID 30S LAST NIGHT...SEE NO REASON WHY THAT
WILL NOT HAPPEN AGAIN. THIS MEANS THAT OUR TYPICAL WISCONSIN COLD
SPOTS COULD SEE SOME FROST. NOT ENOUGH OF AN EXPANSIVE AREA OF COLD
TEMPS IS FORECAST TO WARRANT A FROST ADVISORY...THOUGH. WEST OF THE
MISSISSIPPI RIVER...INCREASING WINDS SHOULD ALLOW TEMPERATURES TO
STAY WARMER THERE. WITH INCREASING SUNSHINE AND SOUTHERLY WINDS ON
TUESDAY...AS WELL AS 850MB TEMPS CLIMBING TO AROUND 10C BY
18Z...SHOULD ALLOW FOR HIGHS WELL INTO THE 70S. WARMEST TEMPS LIKELY
WEST.

TUESDAY NIGHT AND WEDNESDAY...THE UPPER TROUGHING OVER THE NORTHWEST
U.S. IS PROGGED TO DEEPEN DURING THIS PERIOD. A FAIRLY POTENT
SHORTWAVE EJECTING OUT OF THIS TROUGH THROUGH THE DAKOTAS WILL CAUSE
THE LOW PRESSURE AREA THERE TO LIFT INTO NORTHWEST ONTARIO BY 00Z
THURSDAY. ITS ASSOCIATED COLD FRONT APPEARS TO BE TRENDING
SLOWER...NOW ONLY REACHING WESTERN MINNESOTA BY 00Z THURSDAY. THE
ECMWF HAS BEEN SUGGESTING THIS FOR QUITE AWHILE. ONLY MODEL THAT HAS
THE FRONT APPROACHING THE FORECAST AREA IS THE 21.12Z NAM...AND EVEN
IT HAS TRENDED SLOWER FROM ITS PREVIOUS RUNS. THEREFORE...HAVE
CONSIDERED THE NAM A FAST OUTLIER. ANY CONVECTION IS LIKELY TO BE
HIGHLY TIED TO THE FRONT...GIVEN CAPPING PRESENT IN THE WARM SECTOR
AHEAD OF IT. THEREFORE...HAVE DRIED OUT MUCH OF THE FORECAST EXCEPT
FOR A SMALL AREA IN SOUTHEAST MINNESOTA WHICH IS CLOSEST TO THE
FRONTAL BOUNDARY. THESE SMALL CHANCES MAY BE ABLE TO BE PULLED IN
LATER FORECASTS. A BREEZY SOUTH WIND WILL HELP KEEP TEMPERATURES UP
TUESDAY NIGHT INTO THE 50S IN MOST LOCATIONS. SOME OF SOUTHEAST MN
MAY NOT DROP BELOW 60...MEANWHILE THE COLD SPOTS OF WISCONSIN COULD
DECOUPLE AND DROP INTO THE UPPER 40S. MUCH WARMER 850MB TEMPS ARE
PROGGED FOR WEDNESDAY...ON THE ORDER OF 16-18C. NORMALLY THIS COULD
PRODUCE HIGHS OF 85 TO 90. HOWEVER...THERE IS INCREASING CIRRUS
THROUGH THE DAY TO TEMPER HIGHS SOMEWHAT.

WEDNESDAY NIGHT AND THURSDAY...ANOTHER SURFACE LOW IS PROGGED TO
FORM OVER SOUTHEAST COLORADO LATE WEDNESDAY. A POTENT SHORTWAVE
EJECTING OUT OF THE DEEPENING WESTERN TROUGH WILL LIFT THIS LOW
NORTHEAST...RIDING UP THE COLD FRONT AND CROSSING CENTRAL MINNESOTA
ON THURSDAY. THE 21.12Z GFS/UKMET BOTH DEPICT SOME QPF WEDNESDAY
NIGHT OVER WISCONSIN...BUT THESE SEEM ODD GIVEN OUR FORECAST AREA IS
UNDERNEATH THE MAIN MOISTURE TRANSPORT STREAM WITHOUT MOISTURE
CONVERGENCE...AS WELL AS CAPPING ALOFT TO ELEVATED CONVECTION.
THEREFORE...FOR WEDNESDAY NIGHT...KEPT ALL PRECIPITATION CHANCES
OVER FAR NORTHWEST SECTIONS OF THE FORECAST AREA. THESE CHANCES ARE
STILL LOW...20-30...BECAUSE THE FRONTOGENETICAL ZONE ASSOCIATED WITH
THE COLD FRONT LOOKS TO STAY ACTIVE ALONG AND NORTHWEST OF
IT...WHICH KEEPS THE BULK OF THE PRECIPITATION MORE FROM SOUTHWEST
MINNESOTA INTO THE DULUTH AREA. BETTER SHOT EXISTS FOR THE COLD
FRONT TO COME IN ON THURSDAY...IN THIS CASE ASSOCIATED WITH THE NEW
LOW COMING UP. THE 21.12Z GFS REMAINS THE FASTEST MODEL TO DO
SO...WITH THE ECMWF AND ESPECIALLY GEM SUGGESTING SLOWER. LEANED
TOWARDS THE SLOWER PASSAGE...WHICH KEEPS ALL PRECIPITATION CHANCES
OVER THE NORTHWEST HALF OF THE FORECAST AREA. TEMPERATURES BOTH
WEDNESDAY NIGHT AND ESPECIALLY THURSDAY HAVE BEEN WARMED UP...DUE TO
THE SLOWER FRONTAL PASSAGE AND MAINTAINING A LONGER PERIOD OF BREEZY
SOUTH WINDS. THURSDAY COULD TOUCH 90...ESPECIALLY IN THE SOUTHEAST
WHERE MORE SUN IS PRESENT TO COMBINE WITH 850MB TEMPS UP POSSIBLY
NEAR 20C.

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY
325 PM CDT MON MAY 21 2012

MAIN FORECAST CONCERNS ARE ON PRECIPITATION CHANCES AND WHEN THE
HEAT UP WILL COME.

MODELS ARE BECOMING IN MUCH BETTER AGREEMENT ON THE LONG TERM
FORECAST...SO CONFIDENCE IS INCREASING ON WHAT WILL HAPPEN. IN
GENERAL...TROUGHING LOOKS TO REMAIN IN THE WESTERN U.S....
INTENSIFYING BY SATURDAY MORNING. WITH THE DEEPENING TROUGH OUT
WEST...THE RESPONSE IS TO BUILD SOME PRETTY STRONG RIDGING TO THE
EAST. THEREFORE...AFTER WHAT LOOKS TO BE A COLD FRONTAL PASSAGE
THURSDAY NIGHT...THAT COLD FRONT WILL NOT BE ABLE TO DROP TOO FAR
SOUTH. MAINTAINED SOME CHANCES OF SHOWERS AND THUNDERSTORMS FOR
THURSDAY NIGHT...AND THESE MAY NEED TO BE INCREASED OVER WESTERN
SECTIONS WITH A SHORTWAVE PROGGED TO COME OUT. IN FACT...IF THE
21.12Z ECMWF/GEM ARE CORRECT...SOME OF THE STORMS THURSDAY NIGHT
COULD BE SEVERE. WESTERN SECTIONS OF THE AREA LOOK TO GET A BREAK
FROM PRECIPITATION ON FRIDAY WITH THE FRONT PASSED...BUT STILL
MAINTAINED A CHANCE ELSEWHERE SINCE THE FRONT IS STILL MOVING
THROUGH. DEFINITELY COOLER ON FRIDAY BEHIND THE FRONT...BUT STILL
SEASONABLE. FRONT SHOULD LAY UP IN SOUTHERN IOWA FRIDAY NIGHT AND
THEN BEGIN TO RETREAT NORTH AS A WARM FRONT AS THE UPPER RIDGE
STRENGTHENS. MOISTURE TRANSPORT NORTH OF THE FRONT COULD YIELD
CONVECTION FRIDAY NIGHT THROUGH SATURDAY. CANNOT RULE OUT SOME OF
THIS BEING SEVERE TOO. 850MB TEMPS CLIMB TO 20C OR HIGHER SOUTH OF
THE FRONT...WHICH MEANS ON SATURDAY THERE IS POTENTIAL FOR A 20
DEGREE OR MORE SPREAD ACROSS THE FORECAST AREA.

MODELS AGREE THAT THE WESTERN TROUGH BEGINS EJECTING OUT SATURDAY
NIGHT...ALLOWING THE RIDGE AND WARM SECTOR TO BUILD OVER THE
FORECAST AREA. THIS MEANS THE CONVECTION SHOULD SLOWLY SHIFT
NORTH...ALLOWING FOR HEAT AND LIKELY SOME HUMIDITY TO MOVE IN.
RAISED HIGHS ON SUNDAY TO THE MID 80S TO NEAR 90...BUT FURTHER
INCREASES COULD BE NEEDED. SAME GOES FOR LOWS SATURDAY NIGHT AND
SUNDAY NIGHT WHERE POTENTIAL EXISTS FOR TEMPERATURES TO NOT DIP
BELOW 70. LAST ISSUE IS A COLD FRONT PROGGED TO COME AT THE AREA FOR
SUNDAY NIGHT AND MONDAY...ASSOCIATED WITH THE EJECTING WESTERN
TROUGH. THE GFS IS THE FASTEST ON THIS FRONT...WHEREAS THE 21.12Z
ECMWF HAS SLOWED DOWN FROM ITS PREVIOUS RUN. FOR NOW HAVE FOLLOWED A
CONSENSUS AND INCLUDED 20-40 PERCENT CHANCES FOR SUNDAY NIGHT AND
MONDAY. HOWEVER...WOULD NOT BE SURPRISED IF THE SLOWER FRONTAL
TIMING PANS OUT...RESULTING IN A WARMER AND DRIER FORECAST.

IN SUMMARY...SOME POTENTIAL FOR SEVERE STORMS THURSDAY NIGHT AND
FRIDAY NIGHT/SATURDAY...THEN HEATING UP FOR THE END OF MEMORIAL DAY
WEEKEND.

&&

.AVIATION...THROUGH 06Z WEDNESDAY
1145 PM CDT MON MAY 21 2012

HIGH PRESSURE WILL MOVE EAST INTO EASTERN WISCONSIN OVERNIGHT. AS
THIS OCCURS...THE WINDS WILL SHIFT TO THE SOUTH AND THEN INCREASE
ON TUESDAY MORNING AS THE PRESSURE GRADIENT TIGHTENS ON THE BACK
SIDE OF THE HIGH PRESSURE. AS DIURNAL MIXING OCCURS...THE WIND
GUSTS ACROSS SOUTHEAST MINNESOTA WILL CLIMB INTO THE 20 TO 30 KNOT
RANGE...AND 15 TO 25 KNOTS ACROSS WESTERN WISCONSIN. WITH THE LOSS
OF DIURNAL HEATING DURING THE EARLY EVENING...THE WIND GUSTS WILL
QUICKLY SUBSIDE AT BOTH LOCATIONS.

OTHER THAN OCCASIONALLY BOUTS OF SCATTERED 10-20K CLOUDS...SKIES
WILL BE MOSTLY CLEAR.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
325 PM CDT MON MAY 21 2012

WI...NONE.
MN...NONE.
IA...NONE.

&&

$$

SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE








AREA FORECAST DISCUSSION

NWS TAUNTON MA

 1020 AM EDT TUE MAY 22 2012

.SYNOPSIS...
LOW PRESSURE WILL PASS EAST OF CAPE COD THIS AFTERNOON.
SOUTHEASTERLY FLOW OVER SOUTHERN NEW ENGLAND LATE THIS WEEK MAY
RESULT IN SHOWERS AND THUNDERSTORMS. CHANCE FOR STORMS INCREASES
SATURDAY AS A COLD FRONT APPROACHES THE AREA.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE...THREE BANDS OF SHOWERS ON THE RADAR. ONE IS
ACROSS SOUTHERN NH AND WESTERN MASS...THE SECOND IS SOUTHEAST MASS
AND RI AND EASTERN CT...THE THIRD IS MOVING INTO THE ISLANDS.
THESE ARE SLIDING NORTH-NORTHWEST. THE UPDATE GOES WITH LIKELY TO
CATEGORICAL POPS ROUGHLY DRAWN TO MIRROR THESE BANDS. POPS
DIMINISH TO CHANCE DURING THE AFTERNOON AS THE OFFSHORE LOW MOVES
PAST. WINDS HAVE BEEN BLENDED WITH THE LATEST HRRR GUIDANCE. BASIC
IDEA OF THE FORECAST REMAINS INTACT.

ORIGINAL DISCUSSION...
MID LEVEL CIRCULATION EAST OF NJ COAST WITH TROWAL SIGNATURE IN
PLACE TO THE NORTH ACROSS NEW ENG. BANDS OF MAINLY LIGHT SHOWERS
ARE LIFTING NORTH ACROSS SNE EARLY THIS MORNING. SFC REFLECTION IN
THE FORM OF A WEAK WAVE IS FORECAST TO TRACK NE AND PASS E OF CAPE
COD TODAY. WEAK EASTERLY LOW LEVEL JET ALONG WITH SOME INSTABILITY
JUST OFFSHORE MAY HELP TO ENHANCE SHOWERS OVER THE CAPE/ISLANDS
THROUGH THE MORNING. OTHERWISE...WILL CONTINUE WITH CHC SHOWERS AS
MID LEVEL SHORTWAVE LIFTS NWD ACROSS THE REGION. EXPECT LOW CLOUDS
TO PERSIST TODAY GIVEN ABUNDANT LOW LEVEL MOISTURE BUT IMPROVING
VSBYS DURING THE DAY. USED A BLEND OF TRADITIONAL MOS GUIDANCE AND
BIAS CORRECTED GRIDS FOR MAX TEMPS. COOLEST TEMPS WILL BE ACROSS E
COASTAL MA WITH MILDEST READINGS IN THE CT VALLEY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
TONIGHT...
MID LEVEL SHORTWAVE AND WEAK SFC WAVE EXIT TO THE EAST WITH WEAK
SFC RIDGING DEVELOPING SO EXPECT MOSTLY DRY CONDITIONS. STILL CANT
RULE OUT A BRIEF SHOWER OR PATCHY DRIZZLE GIVEN THE MOISTURE IN
PLACE SO HAVE SLIGHT CHC POPS...BUT MOST OF THE NIGHT SHOULD BE
DRY.

WEDNESDAY...
NEXT MID LEVEL LOW WILL MOVE TO THE SE US AND SOUTHERN MID ATLC
REGION WITH RIDGING DEVELOPING TO THE NORTH INTO NEW ENG.
HOWEVER...MODELS INDICATE MARGINAL SFC INSTABILITY DEVELOPING AS
DEEP LAYER MOISTURE DECREASES A BIT WHICH MAY ALLOW FOR SOME
BREAKS OF SUNSHINE DEVELOPING...ESPECIALLY INTERIOR. FORECAST
CAPES 500-1000 J/KG AND LI/S -2 TO -3C SO WILL HAVE CHC
SHOWERS/TSTMS. SVR WEATHER NOT ANTICIPATED GIVEN WEAK WIND FIELD AND
MARGINAL MID LEVEL LAPSE RATES...BUT THIS WILL LEAD TO LOCALIZED
HEAVY RAINFALL BEING A THREAT AS PWATS NEAR 1.5".

USED A BLEND OF MAV/MET GUIDANCE FOR MAX TEMPS...MAINLY 75 TO 80
DEGREES...BUT COOLER ALONG THE COAST WHERE SEABREEZES ARE
EXPECTED.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
* UNSETTLED WEATHER CONTINUES THROUGH THE END OF THE WEEK
  * TEMPERATURES ON A GRADUAL WARMING TREND THROUGH EARLY NEXT WEEK

OVERVIEW...
AGREEMENT AMONGST THE 00Z MODELS IS PRETTY DISMAL IN REGARDS TO
TIMING.  THE GFS IS 12 TO 24 HOURS FASTER THAN THE ECMWF WITH MOST
FEATURES THROUGH THE PERIOD.  OVERALL...AN UPPER RIDGE MOVES
OFFSHORE THURSDAY FOLLOWED BY AN UPPER TROUGH MOVING ACROSS SOUTHERN
NEW ENGLAND.  ALL THIS OCCURS WITH HIGH PRESSURE OVER MAINE AND NOVA
SCOTIA...PROVIDING A MOIST SOUTHEASTERLY FLOW.  LOW PRESSURE MOVING
THROUGH QUEBEC OVER THE WEEKEND BRINGS A COLD FRONT THROUGH SOUTHERN
NEW ENGLAND SATURDAY.  THERE ARE A FEW MORE DISCREPANCIES IN THE
MODELS SUNDAY AND MONDAY.  A WARM FRONT WILL ADVANCE NORTHWARD
THROUGH THE REGION SOMETIME DURING THIS PERIOD...RESULTING IN WARMER
TEMPERATURES AND ANOTHER SHOT OF RAIN.

DETAILS...
WEDNESDAY NIGHT INTO THURSDAY...CLOUDY AND UNSETTLED WEATHER IS
EXPECTED THROUGH THIS PERIOD WITH THE BEST SHOT OF SHOWERS AND/OR
THUNDERSTORMS ON THURSDAY AFTERNOON.  DECENT MID LEVEL LAPSE RATES
AND CONVECTIVE PARAMETERS INDICATE AN UNSTABLE ATMOSPHERE SO WILL
KEEP CHANCE OF THUNDER IN THE GRIDS FOR THURSDAY AFTERNOON AND
EVENING.  USED A BLEND OF MOS FOR TEMPERATURES YIELDING TEMPERATURES
SLIGHTLY ABOVE NORMAL IN THE MID TO UPPER 70S.  WITH DEWPOINTS WELL
INTO THE 50S AND EVEN INTO THE LOW 60S AT TIMES OVERNIGHT AND MOIST
GROUND...EXPECT FOG TO DEVELOP OVERNIGHT.

FRIDAY...SOUTHWEST SURFACE FLOW AHEAD OF A COLD FRONT TRAILING A LOW
PRESSURE IN QUEBEC WILL YIELD ANOTHER DAY OF ABOVE NORMAL
TEMPERATURES.  ADDITIONALLY...SOUTHWEST WINDS WILL BRING IN MOISTURE
AND HIGHER DEWPOINTS.  SHOWERS ARE LIKELY TO FORM DIURNALLY WITH
MODELS HINTING AT A POTENTIAL FOR THUNDER.  SOMEWHAT UNCERTAIN AT
THIS POINT SO HAVE LEFT THUNDER OUT OF THE GRIDS FOR THE TIME
BEING.  FOG IS POSSIBLE AGAIN DURING THE OVERNIGHT PERIOD.

SATURDAY...LOW PRESSURE MAKES ITS WAY ACROSS QUEBEC BRINGING A COLD
FRONT ACROSS SOUTHERN NEW ENGLAND AT SOME POINT SATURDAY.  THERE IS
SOME DIFFERENCE BETWEEN THE MODELS ON TIMING FOR THIS.  AHEAD OF THE
FRONT...MID LEVEL LAPSE RATES INCREASE AND SOUTHWEST FLOW AT THE
SURFACE WILL BRING IN HIGHER DEWPOINTS.  THIS WILL LIKELY RESULT IN
WIDESPREAD SHOWERS.  AGAIN...THUNDER IS A POSSIBILITY WITH THESE
SHOWERS...BUT THIS BEING DAY 5 AND THERE REMAINING SOME UNCERTAINTY
HERE...WILL LEAVE OUT OF THE GRIDS.

SUNDAY AND MONDAY...MOST MODEL DISCREPANCIES EXIST HERE.  THERE IS
SOME INDICATION OF GRADUALLY WARMING TEMPERATURES THROUGH THE
HOLIDAY WEEKEND.  ECMWF SHOWS A SLIGHT COOL OFF SUNDAY BUT
REBOUNDING MONDAY WHILE THE GFS HAS TEMPS WARMING THROUGH THIS
PERIOD.  A WARM FRONT WILL MOVE THROUGH THE REGION DURING THIS TIME
BRINGING WARM...MOIST AIR INTO THE AREA AND PRODUCING SHOWERS AND
POSSIBLY THUNDERSTORMS.

&&

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
  LOW...LESS THAN 30 PERCENT
  MODERATE...30 PERCENT TO 60 PERCENT
  HIGH...GREATER THAN 60 PERCENT

OVERVIEW...
MODERATE CONFIDENCE IN TAFS. IFR/LIFR EXPECTED TO PREVAIL THROUGH
AFTERNOON NEAR COAST...WHILE CONDITIONS LOWER TO IFR ACROSS
INTERIOR. NOT MUCH HOPE FOR CIGS TO IMPROVE GIVEN CONTINUED
ONSHORE FLOW.

KBOS TAF...HIGH CONFIDENCE IN LIFR CONDITIONS THROUGH AFTERNOON.

KBDL TAF...HIGH CONFIDENCE IN CONDITIONS LOWERING TO IFR THIS
AFTERNOON.

OUTLOOK...WEDNESDAY NIGHT THOUGH SATURDAY...

WEDNESDAY NIGHT...LOW CONFIDENCE. MVFR WITH POCKETS OF IFR IN FOG
ALONG SOUTH COAST.

THURSDAY THROUGH SATURDAY...LOW TO MODERATE CONFIDENCE.  DAYTIME
GENERALLY VFR WITH PERIODS OF MVFR IN SHOWERS AND POSSIBLE TSRA.
NIGHTTIME MVFR WITH PERIODS OF IFR IN FOG.

&&

.MARINE...
MODERATE TO HIGH CONFIDENCE THROUGH WEDNESDAY. WINDS WILL REMAIN
WELL BELOW SCA THRESHOLDS...BUT INCREASING SE SWELL WILL RESULT IN
SEAS BUILDING TO 5-7 FT OVER THE S COASTAL WATERS. WNAWAVE
GUIDANCE HAS BEEN OVERDONE ON SEAS SO WE USED MORE CONSERVATIVE
SWAN NAM. SCA FOR HAZARDOUS SEAS WILL CONTINUE.

OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...

SEAS REMAIN BELOW 5 FEET THROUGH THE PERIOD WITH HIGH PRESSURE OVER
MAINE AND THE MARITIMES.  SIMILARLY WINDS WILL REMAIN GENERALLY OUT
OF THE SOUTH AND BELOW 25 KTS.  HIGH CONFIDENCE IN FOG REDUCING
VISIBILITIES AT TIMES...MOSTLY DURING THE OVERNIGHT PERIODS.
SHOWERS AND THUNDERSTORMS ARE A LOW PROBABILITY EACH AFTERNOON AND
EVENING.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
     WEDNESDAY FOR ANZ235-237-254>256.

&&

$$
SYNOPSIS...KJC
NEAR TERM...WTB/KJC
SHORT TERM...KJC
LONG TERM...RLG
AVIATION...JWD
MARINE...KJC/RLG








AREA FORECAST DISCUSSION

NWS TAUNTON MA

 1012 AM EDT TUE MAY 22 2012

.SYNOPSIS...
LOW PRESSURE WILL PASS EAST OF CAPE COD THIS AFTERNOON.
SOUTHEASTERLY FLOW OVER SOUTHERN NEW ENGLAND LATE THIS WEEK MAY
RESULT IN SHOWERS AND THUNDERSTORMS. CHANCE FOR STORMS INCREASES
SATURDAY AS A COLD FRONT APPROACHES THE AREA.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE...THREE BANDS OF SHOWERS ON THE RADAR. ONE IS
ACROSS SOUTHERN NH AND WESTERN MASS...THE SECOND IS SOUTHEAST MASS
AND RI AND EASTERN CT...THE THIRD IS MOVING INTO THE ISLANDS.
THESE ARE SLIDING NORTH-NORTHWEST. THE UPDATE GOES WITH LIKELY TO
CATEGORICAL POPS ROUGHLY DRAWN TO MIRROR THESE BANDS. POPS
DIMINISH TO CHANCE DURING THE AFTERNOON AS THE OFFSHORE LOW MOVES
PAST. WINDS HAVE BEEN BLENDED WITH THE LATEST HRRR GUIDENCE. BASIC
IDEA OF THE FORECAST REMAINS INTACT.

ORIGINAL DISCUSSION...
MID LEVEL CIRCULATION EAST OF NJ COAST WITH TROWAL SIGNATURE IN
PLACE TO THE NORTH ACROSS NEW ENG. BANDS OF MAINLY LIGHT SHOWERS
ARE LIFTING NORTH ACROSS SNE EARLY THIS MORNING. SFC REFLECTION IN
THE FORM OF A WEAK WAVE IS FORECAST TO TRACK NE AND PASS E OF CAPE
COD TODAY. WEAK EASTERLY LOW LEVEL JET ALONG WITH SOME INSTABILITY
JUST OFFSHORE MAY HELP TO ENHANCE SHOWERS OVER THE CAPE/ISLANDS
THROUGH THE MORNING. OTHERWISE...WILL CONTINUE WITH CHC SHOWERS AS
MID LEVEL SHORTWAVE LIFTS NWD ACROSS THE REGION. EXPECT LOW CLOUDS
TO PERSIST TODAY GIVEN ABUNDANT LOW LEVEL MOISTURE BUT IMPROVING
VSBYS DURING THE DAY. USED A BLEND OF TRADITIONAL MOS GUIDANCE AND
BIAS CORRECTED GRIDS FOR MAX TEMPS. COOLEST TEMPS WILL BE ACROSS E
COASTAL MA WITH MILDEST READINGS IN THE CT VALLEY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
TONIGHT...
MID LEVEL SHORTWAVE AND WEAK SFC WAVE EXIT TO THE EAST WITH WEAK
SFC RIDGING DEVELOPING SO EXPECT MOSTLY DRY CONDITIONS. STILL CANT
RULE OUT A BRIEF SHOWER OR PATCHY DRIZZLE GIVEN THE MOISTURE IN
PLACE SO HAVE SLIGHT CHC POPS...BUT MOST OF THE NIGHT SHOULD BE
DRY.

WEDNESDAY...
NEXT MID LEVEL LOW WILL MOVE TO THE SE US AND SOUTHERN MID ATLC
REGION WITH RIDGING DEVELOPING TO THE NORTH INTO NEW ENG.
HOWEVER...MODELS INDICATE MARGINAL SFC INSTABILITY DEVELOPING AS
DEEP LAYER MOISTURE DECREASES A BIT WHICH MAY ALLOW FOR SOME
BREAKS OF SUNSHINE DEVELOPING...ESPECIALLY INTERIOR. FORECAST
CAPES 500-1000 J/KG AND LI/S -2 TO -3C SO WILL HAVE CHC
SHOWERS/TSTMS. SVR WEATHER NOT ANTICIPATED GIVEN WEAK WIND FIELD AND
MARGINAL MID LEVEL LAPSE RATES...BUT THIS WILL LEAD TO LOCALIZED
HEAVY RAINFALL BEING A THREAT AS PWATS NEAR 1.5".

USED A BLEND OF MAV/MET GUIDANCE FOR MAX TEMPS...MAINLY 75 TO 80
DEGREES...BUT COOLER ALONG THE COAST WHERE SEABREEZES ARE
EXPECTED.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
* UNSETTLED WEATHER CONTINUES THROUGH THE END OF THE WEEK
  * TEMPERATURES ON A GRADUAL WARMING TREND THROUGH EARLY NEXT WEEK

OVERVIEW...
AGREEMENT AMONGST THE 00Z MODELS IS PRETTY DISMAL IN REGARDS TO
TIMING.  THE GFS IS 12 TO 24 HOURS FASTER THAN THE ECMWF WITH MOST
FEATURES THROUGH THE PERIOD.  OVERALL...AN UPPER RIDGE MOVES
OFFSHORE THURSDAY FOLLOWED BY AN UPPER TROUGH MOVING ACROSS SOUTHERN
NEW ENGLAND.  ALL THIS OCCURS WITH HIGH PRESSURE OVER MAINE AND NOVA
SCOTIA...PROVIDING A MOIST SOUTHEASTERLY FLOW.  LOW PRESSURE MOVING
THROUGH QUEBEC OVER THE WEEKEND BRINGS A COLD FRONT THROUGH SOUTHERN
NEW ENGLAND SATURDAY.  THERE ARE A FEW MORE DISCREPANCIES IN THE
MODELS SUNDAY AND MONDAY.  A WARM FRONT WILL ADVANCE NORTHWARD
THROUGH THE REGION SOMETIME DURING THIS PERIOD...RESULTING IN WARMER
TEMPERATURES AND ANOTHER SHOT OF RAIN.

DETAILS...
WEDNESDAY NIGHT INTO THURSDAY...CLOUDY AND UNSETTLED WEATHER IS
EXPECTED THROUGH THIS PERIOD WITH THE BEST SHOT OF SHOWERS AND/OR
THUNDERSTORMS ON THURSDAY AFTERNOON.  DECENT MID LEVEL LAPSE RATES
AND CONVECTIVE PARAMETERS INDICATE AN UNSTABLE ATMOSPHERE SO WILL
KEEP CHANCE OF THUNDER IN THE GRIDS FOR THURSDAY AFTERNOON AND
EVENING.  USED A BLEND OF MOS FOR TEMPERATURES YIELDING TEMPERATURES
SLIGHTLY ABOVE NORMAL IN THE MID TO UPPER 70S.  WITH DEWPOINTS WELL
INTO THE 50S AND EVEN INTO THE LOW 60S AT TIMES OVERNIGHT AND MOIST
GROUND...EXPECT FOG TO DEVELOP OVERNIGHT.

FRIDAY...SOUTHWEST SURFACE FLOW AHEAD OF A COLD FRONT TRAILING A LOW
PRESSURE IN QUEBEC WILL YIELD ANOTHER DAY OF ABOVE NORMAL
TEMPERATURES.  ADDITIONALLY...SOUTHWEST WINDS WILL BRING IN MOISTURE
AND HIGHER DEWPOINTS.  SHOWERS ARE LIKELY TO FORM DIURNALLY WITH
MODELS HINTING AT A POTENTIAL FOR THUNDER.  SOMEWHAT UNCERTAIN AT
THIS POINT SO HAVE LEFT THUNDER OUT OF THE GRIDS FOR THE TIME
BEING.  FOG IS POSSIBLE AGAIN DURING THE OVERNIGHT PERIOD.

SATURDAY...LOW PRESSURE MAKES ITS WAY ACROSS QUEBEC BRINGING A COLD
FRONT ACROSS SOUTHERN NEW ENGLAND AT SOME POINT SATURDAY.  THERE IS
SOME DIFFERENCE BETWEEN THE MODELS ON TIMING FOR THIS.  AHEAD OF THE
FRONT...MID LEVEL LAPSE RATES INCREASE AND SOUTHWEST FLOW AT THE
SURFACE WILL BRING IN HIGHER DEWPOINTS.  THIS WILL LIKELY RESULT IN
WIDESPREAD SHOWERS.  AGAIN...THUNDER IS A POSSIBILITY WITH THESE
SHOWERS...BUT THIS BEING DAY 5 AND THERE REMAINING SOME UNCERTAINTY
HERE...WILL LEAVE OUT OF THE GRIDS.

SUNDAY AND MONDAY...MOST MODEL DISCREPANCIES EXIST HERE.  THERE IS
SOME INDICATION OF GRADUALLY WARMING TEMPERATURES THROUGH THE
HOLIDAY WEEKEND.  ECMWF SHOWS A SLIGHT COOL OFF SUNDAY BUT
REBOUNDING MONDAY WHILE THE GFS HAS TEMPS WARMING THROUGH THIS
PERIOD.  A WARM FRONT WILL MOVE THROUGH THE REGION DURING THIS TIME
BRINGING WARM...MOIST AIR INTO THE AREA AND PRODUCING SHOWERS AND
POSSIBLY THUNDERSTORMS.

&&

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
  LOW...LESS THAN 30 PERCENT
  MODERATE...30 PERCENT TO 60 PERCENT
  HIGH...GREATER THAN 60 PERCENT

OVERVIEW...
MODERATE CONFIDENCE IN TAFS. IFR/LIFR CONDITIONS WILL LIKELY
PREVAIL FOR MUCH OF THE REGION THROUGH THE MORNING...POSSIBLY
LIFTING TO MVFR IN THE INTERIOR DURING THE AFTERNOON. CONDITIONS
DROPPING BACK TO IFR/LIFR TONIGHT BUT FOG MAY NOT BE AS DENSE AND
WIDESPREAD AS LOW LEVEL WINDS TURN S/SW. GRADUAL IMPROVEMENT TO
VFR/MVFR EXPECTED DURING WED WITH SCT SHOWERS/TSTMS POSSIBLE...BUT
MVFR/IFR CIGS COULD LINGER ALONG THE S COAST ALL DAY WED.

KBOS TAF...HIGH CONFIDENCE IN LIFR CONDITIONS THROUGH 14Z...THEN
IMPROVING VSBYS EXPECTED DURING THE DAY BUT CIGS LIKELY REMAINING
IFR THROUGH TONIGHT.

KBDL TAF...MODERATE CONFIDENCE. AREAS OF MVFR. CIGS MAY DROP BACK
TO IFR LATE TONIGHT.

OUTLOOK...WEDNESDAY NIGHT THOUGH SATURDAY...

WEDNESDAY NIGHT...LOW CONFIDENCE. MVFR WITH POCKETS OF IFR IN FOG
ALONG SOUTH COAST.

THURSDAY THROUGH SATURDAY...LOW TO MODERATE CONFIDENCE.  DAYTIME
GENERALLY VFR WITH PERIODS OF MVFR IN SHOWERS AND POSSIBLE TSRA.
NIGHTTIME MVFR WITH PERIODS OF IFR IN FOG.

&&

.MARINE...
MODERATE TO HIGH CONFIDENCE THROUGH WEDNESDAY. WINDS WILL REMAIN
WELL BELOW SCA THRESHOLDS...BUT INCREASING SE SWELL WILL RESULT IN
SEAS BUILDING TO 5-7 FT OVER THE S COASTAL WATERS. WNAWAVE
GUIDANCE HAS BEEN OVERDONE ON SEAS SO WE USED MORE CONSERVATIVE
SWAN NAM. SCA FOR HAZARDOUS SEAS WILL CONTINUE.

OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...

SEAS REMAIN BELOW 5 FEET THROUGH THE PERIOD WITH HIGH PRESSURE OVER
MAINE AND THE MARITIMES.  SIMILARLY WINDS WILL REMAIN GENERALLY OUT
OF THE SOUTH AND BELOW 25 KTS.  HIGH CONFIDENCE IN FOG REDUCING
VISIBILITIES AT TIMES...MOSTLY DURING THE OVERNIGHT PERIODS.
SHOWERS AND THUNDERSTORMS ARE A LOW PROBABILITY EACH AFTERNOON AND
EVENING.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
     WEDNESDAY FOR ANZ235-237-254>256.

&&

$$
SYNOPSIS...KJC
NEAR TERM...WTB/KJC
SHORT TERM...KJC
LONG TERM...RLG
AVIATION...KJC/RLG
MARINE...KJC/RLG









AREA FORECAST DISCUSSION

NWS TALLAHASSEE FL

 1019 AM EDT Tue May 22 2012

.MESOSCALE UPDATE...
The convective forecast for today was complicated by thunderstorms
that that had moved southeast across Alabama overnight and then
dissipated over the past 1-2 hours near the northwest corner of
our forecast area. Basically no model handled this activity with
any kind of skill; to illustrate that point, none of the models in
a 25-member storm scale ensemble model from OU/CAPS had any storms
in the area of TOI/DHN prior to 15z. The global models and other
higher resolution models produced similar results.

11z HRRR model run finally initialized the small cluster of storms
and related cold pool fairly well. It also correctly shows the new
convection developing along a surface trough axis just offshore.
Therefore, this was used as the basis for our forecast updates
this morning.

Initial development of storms today appears most likely 15-17z
(in the next 3 hours) near the I-65 corridor, or just to the
northwest of our forecast area. This is the scenario portrayed by
the HRRR, low-level convergence is increasing in this area on the
NW side of the residual cold pool / outflow, and an ACCAS field is
in the process of developing. The HRRR then develops things east
to ABY-MAI-DTS by 19z (3pm EDT). We will also need to keep an eye
on the storm cluster offshore, as it would be on track to clip the
Cape San Blas area around 16z if it holds together.

Severe threat still looks to be mainly damaging winds. Deep
inverted-V signature still showing up in the sub-cloud layer on
most of the model forecast soundings. Maximum delta theta-e values
are around 20-25C as well, on the lower cusp of favorable
downburst parameter space. With deep mixing expected today,
dewpoints are likely to fall back into the 50s. Modifying the 12z
TAE sounding for surface conditions of about 88/56 yields SBCAPE
around 1000 j/kg. The BMX sounding just upstream shows a mid-level
temperature profile about 1-2C cooler as it was launched into the
cold pocket of air aloft at the center of the digging shortwave.
If mid-level temperatures in the NW part of our area cool to the
BMX profile - it would add about 600 j/kg of CAPE to the sounding.
With steepening mid-level lapse rates, some hail to around 1 inch
in diameter couldn`t be ruled out either. Slight Risk by SPC still
looks on target. We are expecting scattered thunderstorms. Most of
the storms will produce some sort of gusty winds, and a few that
can build taller cores or deeper/stronger cold pools could produce
some wind gusts up to around 50kt.

High temperatures were nudged up closer to observed values from
yesterday as the low-level temperature profile has changed very
little in the past 24 hours. Grid/product updates will be out
shortly.

&&

.PRELIMINARY POINT TEMPS/POPS...
Tallahassee   90  64  91  65  93 /  50  30  20  10  10
Panama City   84  69  88  67  91 /  40  20  20  10  10
Dothan        90  65  93  66  94 /  60  30  20  10  10
Albany        90  64  91  65  93 /  50  30  20  10  10
Valdosta      92  63  91  64  92 /  50  40  20  10  10
Cross City    90  65  90  64  92 /  20  20  20  10  20
Apalachicola  85  67  86  68  84 /  30  10  20  10  10

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
AL...None.
GA...None.
FL...Fire Weather Watch from Wednesday afternoon through Wednesday
     evening for Calhoun-Gadsden-Holmes-Inland Jefferson-Inland
     Walton-Jackson-Lafayette-Leon-Liberty-Madison-Washington.

GM...None.

&&

$$

08-Lamers







AREA FORECAST DISCUSSION

NWS WILMINGTON NC

 1047 AM EDT TUE MAY 22 2012

.SYNOPSIS...
A SOUTHWESTERLY FLOW OF LOW LEVEL MOISTURE WILL REMAIN IN PLACE OVER
THE NEXT FEW DAYS WHILE AN UPPER LEVEL DISTURBANCE TRIGGERS
THUNDERSTORMS THIS AFTERNOON THROUGH THURSDAY. AS THIS SYSTEM
EXITS...A WARMUP IS EXPECTED LATE IN THE WEEK AND THROUGH THE
HOLIDAY WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM TUESDAY...TROPICAL DEPRESSION ALBERTO IS NO MORE. THE
CONVECTION HAS BEEN SHEARED OFF AND AWAY FROM THE LOW-LEVEL
CIRCULATION MEANING THERE IS NO LONGER A METHOD FOR ALBERTO TO
EVACUATE AIR AND MAINTAIN LOWER PRESSURES IN THE CENTER OF THE
CIRCULATION. ALBERTO`S REMNANT CIRCULATION IS CAUGHT UP IN THE
SOUTHWEST FLOW AHEAD OF AN INCOMING NEGATIVELY TILTED UPPER LEVEL
TROUGH THAT WILL MOVE FROM THE ALABAMA/GEORGIA BORDER THIS MORNING
INTO SOUTH CAROLINA TONIGHT. THE NEGATIVE TILT SHOULD BECOME SO
EXTREME TONIGHT THE SYSTEM ACTUALLY WILL CUT OFF INTO A CLOSED UPPER
LOW WHICH SHOULD WOBBLE SLOWLY OVERHEAD WEDNESDAY. FALLING MID-LEVEL
TEMPERATURES AND A JUICY SUBTROPICAL AIRMASS HERE AT THE SURFACE
SPELL GROWING VERTICAL INSTABILITY...WITH CAPE VALUES RISING TO
AROUND 1500 J/KG THIS AFTERNOON.  WITH THE HELP OF MESOSCALE LIFT
PROVIDED BY THE SEABREEZE FRONT...SHOWERS AND THUNDERSTORMS SHOULD
DEVELOP EARLY THIS AFTERNOON JUST INLAND FROM THE COAST. THE ONLY
AREAS THAT MIGHT BE COMPLETELY SPARED ARE THE SOUTH-FACING BEACHES
WHERE COOLER ONSHORE WINDS BEHIND THE SEABREEZE WILL DEVELOP EARLY
ENOUGH THIS AFTERNOON. THE LATEST HRRR SHOWS THIS CLASSIC WEATHER
PATTERN WELL AND IS THE BASIS FOR OUR MORNING FORECAST UPDATE.

BY MID TO LATE AFTERNOON CONTINUED HEATING INLAND AND THE APPROACH
OF THE SURFACE COLD FRONT SHOULD PRODUCE SCATTERED SHOWERS AND
STORMS INLAND AS WELL. SPC HAS CENTRAL SOUTH CAROLINA OUTLOOKED IN A
"SLIGHT RISK" FOR SEVERE WEATHER WITH THE COLDER TEMPERATURES ALOFT
AND BETTER SHEAR PROFILES CLOSER TO THE NEGATIVELY TILTED UPPER
TROUGH. CONVECTIVE ACTIVITY MAY LINGER INTO THE EVENING...WITH
PERHAPS A SECOND ROUND OF SHOWERS AND STORMS OVERNIGHT AS THE CORE
OF THE COLDEST TEMPERATURES ALOFT ROTATE INTO EASTERN SOUTH CAROLINA.

HIGHS TODAY SHOULD REACH THE MID 80S AWAY FROM THE OCEAN. LOWS
TONIGHT SHOULD FALL TO 65-70...WARMEST AT THE BEACHES.

&&

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 AM TUESDAY...COOL POCKET ALOFT ASSOCIATED WITH MID LEVEL
TROUGH MOVES ACROSS WEDNESDAY MORNING. THEREAFTER COMES WEAK HEIGHT
RISES AND WAA BUT A TRAILING VORT MAX SHOULD STILL MANAGE TO TOUCH
OFF SCATTERED AFTERNOON THUNDERSTORMS. FORECAST INSTABILITY AMPLE
ENOUGH TO DRAW ANOTHER SEE TEXT/5% FOR SEVERE FROM SPC...NOTING LACK
OF SHEAR TO SUPPORT ANY LEVEL OF ORGANIZATION IN CONVECTION.
TEMPERATURES WILL BE VERY CLOSE TO CLIMO. FORCING WILL BE ON THE
WANE FOR THE REMAINDER OF THE PERIOD WITH THE EXIT OF THE UPPER
TROUGH. YET ANOTHER VORT COMES THROUGH ON THE HEELS OF THE EXITING
TROUGH THURSDAY AFTERNOON. ITS A MUCH WEAKER FEATURE SO ONLY LOW
END CHANCE POPS APPEAR WARRANTED FOR WHAT SHOULD END UP BEING WIDELY
SCATTERED OR ISOLATED CONVECTIVE COVERAGE. THURSDAY HIGHS AND LOWS
WILL BE VERY CLOSE TO WEDNESDAYS AND THUS CLIMATOLOGY.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 3 AM TUESDAY...UPPER WAVE FROM THE SHORT TERM GOES ON TO
INTERACT WITH AMPLE MOISTURE STREAMING OUT OF THE CARIBBEAN AND
GUIDANCE SUGGESTS LOW PRESSURE GETS INDUCED IN THE BAHAMAS LATER IN
THE PERIOD. WRF SOLUTION APPEARS RATHER CLIMATOLOGICALLY EXTREME AT
THIS POINT BUT GIVEN THAT SSTS WERE WARM ENOUGH TO ALREADY SUPPORT
ALBERTO TOUGH TO RULE OUT. FOR NOW THE SHALLOWER SYSTEM DEPICTED BY
THE GFS SEEMS MORE APPEALING AND THERE WILL BE NO IMPACT LOCALLY ON
FRIDAY AS UPPER RIDGE BUILDS OVER GULF STATES. JUST ISOLATED
CONVECTION AS NORTHERLY FLOW LOCALLY WILL CONTAIN SOME WEAK SHORT
WAVE IMPULSES AND A HEALTHY SEA BREEZE CIRCULATION WILL DEVELOP. NOT
MUCH CHANGES INTO THE HOLIDAY WEEKEND AND WITH THE AFOREMENTIONED
POSSIBLE LOW OUT OF THE PICTURE THE UPPER RIDGE WILL BE THE DOMINANT
PLAYER. TEMPERATURES WILL RISE ABOVE CLIMATOLOGY. SURFACE FLOW WILL
BE A BIT MORE EASTERLY THAN MOST LATE SPRING WARM UPS TEMPERING THE
WARMTH SLIGHTLY AND PUSHING THE SEA BREEZE WELL INLAND. ISOLATED
CONVECTION EACH AFTERNOON MAY BE SHUNTED ALL THE WAY TO WESTERN
ZONES.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 12Z...CONFIDENCE IS HIGH THAT LIGHT FOG WILL IMPROVE QUICKLY
AS INDICATED IN TAFS. VFR IS THEN EXPECTED THE REMAINDER OF THE
MORNING EXCEPT FOR TEMPO MVFR CEILINGS AT THE COASTAL TERMINALS AS
THE SEA BREEZE DEVELOPS...AND TEMPO CONDITIONS IN SHOWERS AT FLO/LBT
BY LATE MORNING.

A COLD FRONT WILL APPROACH FROM THE WEST TODAY BUT IT IS NOT EXPECTED
TO MOVE THROUGH THE TERMINALS. AHEAD OF THE FRONT THERE IS MODERATE
TO HIGH CONFIDENCE SHOWERS AND THUNDERSTORMS WILL DEVELOP. CONVECTION
WILL AFFECT THE FLO/LBT TERMINALS AS EARLY AS 15-17Z AND THE COASTAL
TERMINALS BY 17-19Z. ATTM WILL INDICATE SHOWERS WITH TEMPO MVFR AND
VCTS...ALTHOUGH VCTS MAY BE MORE LIKELY AT THE COASTAL TERMINALS THAN
AT FLO/LBT. SHORT PERIODS OF IFR ARE LIKELY WITH THE THUNDERSTORMS
BUT THE DURATION SHOULD BE TOO SHORT TO MENTION IN TAFS. A SECOND
ROUND OF ACTIVITY IS POSSIBLE LATE THIS AFTERNOON AT FLO/LBT AND THIS
EVENING AT THE COASTAL TERMINALS AS THE UPPER IMPULSE ROTATES
THROUGH.

THUNDERSTORM DEBRIS CLOUDINESS SHOULD SLOWLY SCATTER OUT OVERNIGHT
LEAVING THE WINDOW OPEN FOR BR DEVELOPMENT. ATTM WILL INDICATE ONLY
MVFR CONDITIONS AT FLO/LBT DUE TO LIGHTER SURFACE WINDS AND LESS
POTENTIAL CLOUD COVER. PATCHY DENSE FOG COULD OCCUR ESPECIALLY IN
SHELTERED AREAS WHERE SKIES CLEAR OUT.

EXTENDED OUTLOOK...SCATTERED SHOWERS/MVFR...WITH ISOLATED
THUNDERSTORMS/TEMPO IFR POSSIBLE THROUGH THE EXTENDED PERIOD.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM TUESDAY...ALBERTO IS A DISSIPATING POST-TROPICAL
DEPRESSION LOCATED ABOUT 250 MILES EAST-SOUTHEAST OF CAPE FEAR.
WINDS ARE CURRENTLY SOUTH TO SOUTHWEST ACROSS OUR COASTAL WATERS
INDICATING THERE HAS BEEN NO INFLUENCE FROM ALBERTO`S SMALL
CIRCULATION. OUR WINDS ARE ACTUALLY INFLUENCED BY THE CYCLONIC FLOW
AROUND AN AREA OF LOW PRESSURE AND COLD FRONT CURRENTLY ACROSS THE
INLAND CAROLINAS. THIS SYSTEM IS NOT EXPECTED TO REACH THE COAST...
INSTEAD STALLING TONIGHT AND DISSIPATING ON WEDNESDAY. UNTIL THEN...
SOUTHWEST 10-15 KNOT WINDS ARE EXPECTED...STRONGEST ALONG THE COAST
THIS AFTERNOON AND FARTHER AWAY FROM THE COAST TONIGHT.
THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE SEABREEZE FRONT THIS
AFTERNOON. SOME OF THESE COULD BE ON OR VERY NEAR THE BEACHES...SO
MARINERS WILL WANT TO PAY CLOSE ATTENTION TO THE SKY EARLY THIS
AFTERNOON. THERE SHOULD BE A LULL IN SHOWER/T-STORM ACTIVITY LATER
THIS AFTERNOON INTO EARLY EVENING...BUT NEW SHOWERS AND STORMS MAY
DEVELOP OFFSHORE LATE THIS EVENING AND OVERNIGHT.

SEAS CONTINUE TO BE THE ONE AREA WE ARE RECEIVING AN INFLUENCE FROM
FORMER TROPICAL STORM ALBERTO. 3-4 FT SEAS WILL CONTINUE INTO
TONIGHT AS ALBERTO`S SWELL IS ADDED TO LOCALLY GENERATED WIND WAVES.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...BROAD AND WEAK HIGH PRESSURE ACROSS THE WESTERN
ATLANTIC IN TANDEM WITH PIEDMONT TROUGHINESS TO BRING SSW FLOW ON
WEDNESDAY. A DOMINANT 3 TO 4 FT SEA STATE WILL BE A COMBO OF SW WIND
CHOP AND E SWELL...BOTH COMPONENTS BEING COMPARABLE IN RELATIVE
STRENGTH. CONDITIONS WILL NOT CHANCE TOO MUCH INTO THURSDAY BUT
THEIR IS SOME UNCERTAINTY. LOW PRESSURE WILL MOVE OUT OF THE
CARIBBEAN AND INTO THE BAHAMAS LATE IN THE PERIOD. THERE IS QUITE A
DIFFERENCE IN GUIDANCE WITH RESPECT TO THIS SYSTEMS EVENTUAL FATE.
FOR THIS PERIOD ITS PRESENCE MAY CUT DOWN ON THE SWELL ENERGY BY
INTERRUPTING THE LONG EASTERLY FETCH.

LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3 AM TUESDAY...FOR THE MOST PART A LARGE AREA OF HIGH PRESSURE
ACROSS THE WESTERN ATLANTIC WILL BE RESPONSIBLE FOR THE LOCAL SET OF
WIND AND WAVES. THERE IS A COMPLICATING FACTOR THAT FRIDAY MAY SEE
SOME KIND OF WEAK LOW OF TROPICAL ORIGINS MOVING PARALLEL TO THE
COAST...AND LIKELY WELL OFFSHORE. THERE ARE SOME MODEL SOLUTIONS
THAT HAVE IT CLOSER AND STRONGER AND THEREFORE MUCH OF A FACTOR IN
THE FORECAST. FOR NOW FOLLOWING WEAKER SOLUTIONS THAT SHOW A WEAK
LOW OR OPEN TROUGH IN THE OTHERWISE EASTERLY FLOW BORNE OF
AFOREMENTIONED HIGH. SEAS IN THE 2 TO 4 FT RANGE AS ALTHOUGH WINDS
WILL REMAIN LIGHT THE EASTERLY FETCH LENGTH COULD BE QUITE LONG AND
ALLOW FOR A SIGNIFICANT SWELL COMPONENT.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...MRR






AREA FORECAST DISCUSSION

NWS NORMAN OK

 730 AM CDT TUE MAY 22 2012

.AVIATION...
AN ISOLATED SHOWER OR TWO WILL BE POSSIBLE THROUGH
MID MORNING...OTHERWISE CLOUDS WILL SLOWLY DISSIPATE
DURING THE MORNING.  SOUTH TO SOUTHEAST WINDS WILL
INCREASE BY MID TO LATE MORNING.

&&

.PREV DISCUSSION... /ISSUED 418 AM CDT TUE MAY 22 2012/

DISCUSSION...
MID-LEVEL NORTHWEST TO WEST FLOW WILL GRADUALLY TRANSITION
TO A SOUTHWEST FLOW OVER THE NEXT 48 HOURS AS A BROAD
TROUGH TAKES SHAPE OVER THE WESTERN HALF OF THE CONUS.
MEANWHILE...CONVECTION ACROSS TEXAS PANHANDLE HAS WEAKENED
OVERNIGHT WITH MCV-LIKE FEATURE IN WEAK ECHO RETURNS.
TO THE EAST...ISOLATED SHOWERS HAVE BEEN FORMING ACROSS
THE WESTERN THIRD OF OKLAHOMA FROM HARPER COUNTY TO
KIOWA. NAM12 AND RECENT HRRR RUNS ARE MORE BULLISH
WITH THE DEVELOPMENT OF MORE SHOWERS/STORMS BETWEEN
10-15Z ACROSS WESTERN HALF OF FA. WITH RECENT
DEVELOPMENT WILL ADD 20-30 POPS ACROSS WESTERN 1/3 OF
FA. PRECIP THAT DOES DEVELOP SHOULD GRADUALLY WEAKEN
DURING THE MID TO LATE MORNING.

AFTERNOON CONVECTION MAY DEVELOP WEST OF THE AREA BUT
OVERALL COVERAGE MAY LIMIT CHANCES OF IMPACTING WESTERN
OKLAHOMA..SO WILL KEEP POPS RATHER LOW.

SOUTH WINDS WILL INCREASE SOME TODAY AND WILL BECOME RATHER
GUSTY ON WEDNESDAY AS LOW PRESSURE DEEPENS OVER THE
HIGHER TERRAIN.

A SHORTWAVE WILL MOVE FROM THE CENTRAL ROCKIES INTO THE
UPPER MIDWEST LATE WEDNESDAY INTO THURSDAY. THIS FEATURE
WILL HELP PUSH A WEAK SURFACE BOUNDARY INTO NORTHWEST
AND WEST CENTRAL OKLAHOMA WEDNESDAY NIGHT/EARLY THURSDAY.
RATHER WARM 8H TEMPS AND BETTER FORCING NORTH...SHOULD LIMIT
STORM CHANCES WITH THIS BOUNDARY.

AN UPPER RIDGE WILL BUILD OVER THE SOUTHEAST GOING INTO THE
HOLIDAY WEEKEND...WHILE ANOTHER STORM SYSTEM MOVES ACROSS
THE WESTERN THIRD OF THE US.  EC MODEL STRONGER WITH WESTERN
SYSTEM AND MAY BRING A CHANCE OF STORMS TO WESTERN OKLAHOMA
BY SUNDAY...AS IT LIFTS NORTH INTO THE NORTHERN ROCKIES AND
PLAINS. OVERALL...THE HOLIDAY WEEKEND APPEARS MAINLY DRY AND VERY
WARM/HOT WITH BETTER CHANCES FOR STORMS ACROSS WESTERN OK. MODELS
SIGNAL A RETURN TO A NORTHWEST FLOW BY THE MIDDLE OF NEXT WEEK
WHICH MAY BRING BETTER CHANCES FOR STORMS DURING THE LAST DAYS OF
MAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK  85  65  90  67 /  10  10  10  10
HOBART OK         89  64  95  68 /  10  10  10  10
WICHITA FALLS TX  92  66  97  68 /  10  10  10  10
GAGE OK           89  62  93  62 /  10  10  10  10
PONCA CITY OK     83  65  90  68 /  10  10  10  10
DURANT OK         88  65  93  65 /  10  10   0  10

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&

$$

99/99/01




AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

 803 AM EDT TUE MAY 22 2012

.SYNOPSIS...
A LARGE SCALE TROUGH OF LOW PRESSURE WILL REMAIN IN PLACE ACROSS
THE EASTERN U.S. THROUGH THURSDAY...BRINGING SEVERAL ROUNDS OF
SHOWERS AND A FEW THUNDERSTORMS. A SOUTHWEST FLOW OF WARMER AND
HUMID AIR WILL FOLLOW FOR FRIDAY...AND THE ABOVE NORMAL TEMPERATURES
WILL CONTINUE THROUGH THE UPCOMING WEEKEND. A WEAK COLD FRONT WILL
ATTEMPT TO PUSH SOUTHEAST THROUGH THE REGION SATURDAY AFTERNOON AND
EVENING...BUT COULD STALL OUT ACROSS OR JUST TO THE NORTH OF THE
REGION.

&&

.NEAR TERM /THROUGH TONIGHT/...
MOST OF THE EARLIER MDT TO HVY SHRA HAVE DISSIPATED ACROSS THE
CWA...WITH THE EXCEPTION OF THE NCENT MTNS WHERE A SMALL AREA OF
SHOWERS WAS DRIFTING SLOWLY TO THE NORTH.

NEARLY NORTH/SOUTH AXIS OF BOUNDARY LAYER THETA-E CONVERGENCE
EXTENDED FROM NCENT PENN...TO THE SCENT MTNS AND LAUREL HIGHLANDS
EARLY TODAY. 06Z RUC INDICATES THAT THIS AXIS WILL SHIFT A FEW
LAYERS OF COUNTIES TO THE WEST BY THIS AFTERNOON...WHILE A NOTABLE
AREA OF LLVL MOISTURE DIVERGENCE WILL DRIFT NE AND BECOME LOCATED
ACROSS THE SUSQ VALLEY DURING THE MID AFTERNOON HOURS.

THE MOST NUMEROUS SHOWERS AND THUNDERSTORMS WILL BE CONFINED TO
THE WESTERN HALF OF THE CWA INTO THE LATE AFTERNOON. THE APPROACH
OF A AN 850 MB TROUGH AND RIBBON OF SLIGHTLY STEEPER MID LEVEL
LAPSE RATES LATE THIS AFTERNOON AND TONIGHT WILL HELP TO SHIFT THE
AXIS OF MOST NUMEROUS SHOWERS AND SCTD TSRA TO THE SUSQ VALLEY
POINTS EAST FOR VERY LATE TODAY...INTO EARLY WED MORNING.

THE SLOW MOVEMENT OF THE SHOWERS AND STORMS TODAY /AND PERSISTENT
FOCUS AREA/ COULD LEAD TO SOME MODERATELY HEAVY ADDITIONAL RAINFALL
OF 0.5 TO 1.0 OF AN INCH. LESSER AMOUNTS OF RAIN ARE EXPECTED FOR
THE FAR NW CORNER OF THE CWA...AND ALSO FROM THE SUSQ VALLEY...EAST.
OVERCAST SKIES AND VERY LGT WINDS ALOFT SUGGEST THERE WILL BE VERY
LITTLE THREAT OF SVR WX.

&&

.SHORT TERM /WEDNESDAY/...
THE MEAN LARGE-SCALE TROUGH AT THE SFC AND ALOFT WILL CONTINUE TO
RESIDE RIGHT ALONG THE APPALACHIAN MTN CHAIN THROUGH AT LEAST
WEDNESDAY NIGHT...AS THE DEVELOPING UPPER LOW ACROSS THE TENN VALLEY
LIFTS SLOWLY NE ACROSS THE VIRGINIAS AND PENN. THE PRIMARY AXIS OF
LLVL PWATS AND ASSOCIATED THETA-E CONVERGENCE SHOULD SHIFT SLIGHTLY
TO THE EAST ON WEDNESDAY /BECOMING LOCATED FROM THE UPPER SUSQ
VALLEY...TO THE SCENT MTNS AND LAURELS/...ALONG AND JUST TO THE EAST
OF THE WEAKENING UPPER LOW TRACK.

INSTABILITY RAMPS UP A FEW HUNDRED J/KG IN THE CAPE DEPT
WEDNESDAY...WITH THE BEST CONVECTIVE POTENTIAL ALONG AND TO THE SE
OF A LINE FROM KIPT TO KAOO. VERY WEAK WINDS IN THE LOWEST 15 KFT OF
THE ATMOSPHERE WILL KEEP THE EHI/S ON THE VERY LOW SIDE...WITH THE
MAIN CHARACTERISTIC OF THE CONVECTION BEING IT/S SLOW MOVEMENT AND
LOCALIZED HEAVY RAIN POTENTIAL. PWATS ARE NOT TREMENDOUSLY HIGH -
ONLY 1-2 STANDARD DEVIATIONS ABOVE NORMAL...AND WITH THE EXTENSIVE
CLOUD COVER...HIGH CAPES OF 2000 J/KG OR MORE WILL BE DIFFICULT TO
COME BY. STILL...THE 00Z GEFS AND 03Z SREF TARGET THE SCENT MTNS AND
MID SUSQ VALLEY FOR ABOUT A 60 PERCENT CHC FOR SFC BASED CAPES TO
EXCEED 1200 J/KG.

BASIN AVG RAINFALL AMOUNTS FOR THE NEXT 36 HOURS WILL BE MAINLY IN
THE 0.5 TO 1.0 RANGE. AREAS RECEIVING A FEW TSRA COULD SEE NEARLY
1.5 INCHES /AS INDICATED BY SEVERAL SREF AND GEFS PLUME MEMBERS/.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
A SLOWLY FILLING UPPER LOW WILL DRIFT NE FROM THE CENTRAL
APPALACHIANS AND CROSS SERN PENN ON THURSDAY. WED EVENING
CONVECTION WILL QUICKLY WANE BY 04Z WITH CLOUDY SKIES...LIGHT
WIND AND AREAS OF FOG FOLLOWING FOR THE REST OF THE OVERNIGHT HOURS.
ISOLATED TO SCATTERED...MAINLY AFTERNOON AND EARLY EVENING SHRA
AND TSRA WILL OCCUR THURSDAY AND FRIDAY.

GFS AND OTHERS ARE MORE IN LINE WITH KEEPING FRONT NORTH OF OUR AREA
THIS COMING HOLIDAY WEEKEND...WHILE THE LATEST EC MAKES AN ATTEMPT
TO PUSH THE SHALLOW FRONT TO THE SOUTHERN TIER OF PA SATURDAY NIGHT.
A LARGE POOL OF VERY WARM AIR AT THE SFC AND ALOFT FORMS ACROSS THE
LOWER-MID MISS VALLEY AND OHIO RIVER VALLEY OVER THE UPCOMING
WEEKEND.

THE SOUTHERN EDGE OF WNW FLOW ALOFT /FROM THE GREAT LAKES TO THE
SOUTHERN NEW ENGLAND COAST/ WILL TRANSPORT SOME RIPPLES OF ENERGY
ALOFT ALONG/ABOVE THE LLVL FRONTAL BOUNDARY...POSSIBLY SPARKING SOME
SHOWERS AND TSRA. WE COULD EVEN SEE AN MCS OR TWO TRACK SE INTO THE
WRN AND CENTRAL CWA FROM THE UPPER LAKES REGION SATURDAY MORNING
/AND AGAIN SUNDAY/ WITHIN THE CHANNEL OF PWATS RANGING FROM 32-36MM.
GFS BEST ILLUSTRATES THE POTENTIAL /VIA ITS 500 MB VORT PANELS/ FOR
A FEW RING OF FIRE MCS/S TO SLIDE SE ACROSS MAINLY NRN AND WESTERN
PART OF PENN.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
A LARGE SCALE TROUGH OF LOW PRESSURE WILL REMAIN IN PLACE THROUGH
THURSDAY...BRINGING SEVERAL ROUNDS OF SHOWERS AND A FEW
THUNDERSTORMS.

WIDESPREAD IFR TO MVFR CIGS ACROSS CENTRAL PA THIS MORNING...WILL
IMPROVE SLIGHTLY THROUGH LATE MORNING WITH MOST LOCATIONS BECOMING
MVFR BY 15Z. SHOWERS AGAIN EXPECTED TO DEVELOP OVER MUCH OF THE
REGION BY LATE MORNING...PERSISTING THROUGH THE AFTERNOON - AND
EVEN A RUMBLE OF THUNDER POSS THIS AFTERNOON MAINLY SOUTH /BUT CHC
TOO LOW TO MENTION IN TAFS ATTM/. CIGS SHOULD CONTINUE TO
GRADUALLY IMPROVE THIS AFTERNOON WITH INCREASING AMOUNTS OF VFR
CIGS SPREADING IN FROM THE WEST.

WEAK FRONT PUSHES ACROSS CWA LATE TODAY AND TONIGHT...WITH VFR
CONDITIONS DURING THE EVENING HOURS. BUT PLENTY OF LOW LEVEL
MOISTURE WILL ALLOW FOG AND LOW CIGS TO DEVELOP AFTER
MIDNIGHT...AGAIN RESTRICTING FLYING.

OUTLOOK...
WED...WIDESPREAD MVFR/IFR CIGS AND VSBYS LIKELY IN SHRA AND SCT
TSRA.
THU...PRIMARILY VFR. SCT SHRA/TSRA POSS MAINLY SE.
FRI...PRIMARILY VFR. ISOLD SHRA/TSRA POSS MAINLY SE.
SAT...VFR. A CHC OF A SHRA OR TSRA ACROSS THE NORTH.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/MARTIN
AVIATION...RXR







AREA FORECAST DISCUSSION

NWS FORT WORTH TX

 1042 AM CDT TUE MAY 22 2012

.UPDATE...
THE WEAK SURFACE FRONT SITS NEAR A LINE FROM LEON TO STEPHENVILLE
TO BRYSON. 925 MB FLOW SHOWS WEAK CONVERGENCE NEAR THE
FRONT...WHICH BY THIS AFTERNOON SHOULD BE LOCATED NEAR A BOWIE TO
FORT WORTH TO PALESTINE LINE. MORNING MODELS SUCH AS HRRR AND NAM
AND GFS ARE A BIT MORE AGGRESSIVE DEVELOPING SOME CONVECTION ALONG
THIS LINE SO HAVE ADDED ISOLD POPS FARTHER EAST THAN PREVIOUS.
OTHERWISE...FEW CHANGES TO THE PACKAGE. 84

&&

.AVIATION...
CONCERNS...NONE.

VFR CONDITIONS ARE EXPECTED TO PREVAIL. LIGHT AND VARIABLE WINDS
AT THE BEGINNING OF THE TAF PERIOD WILL BECOME SOUTH-SOUTHEASTERLY
DURING THE MORNING HOURS. WIND SPEEDS TODAY WILL REMAIN AT OR
BELOW 10 KTS. HOWEVER...WIND SPEEDS WILL INCREASE WEDNESDAY
MORNING WITH SUSTAINED SPEEDS OF 15-20 KTS...GUSTING UP TO 30
KTS...FOR MUCH OF THE DAY TOMORROW. THERE IS ANOTHER SMALL CHANCE
FOR SHOWERS AND THUNDERSTORMS TODAY BUT IF ANY STORMS DO DEVELOP
THEY WOULD LIKELY REMAIN WEST OF THE TAF TERMINALS.

82/JLD


&&


.PREV UPDATE...
.UPDATE...
A QUICK UPDATE WAS DONE TO ADJUST THE POPS IN THE WEST THIS
MORNING A LITTLE TO ACCOUNT FOR THE SHOWERS ASSOCIATED WITH THE
VORTEX NORTHWEST OF ABILENE.

58

&&


.PREV DISCUSSION... /ISSUED 340 AM CDT TUE MAY 22 2012/
CIRRUS BLOWOFF FROM THE THUNDERSTORMS IN THE PANHANDLE AND SOUTH
PLAINS OF WEST TEXAS CONTINUE TO SPREAD SOUTHEAST ACROSS NORTH
TEXAS THIS MORNING. EXPECT THESE CLOUDS TO THIN LATER THIS
MORNING...AND WE SHOULD SEE TEMPERATURES CLIMB INTO THE MID 80S
NORTHEAST TO MID 90S SOUTH THIS AFTERNOON. AS A SHORTWAVE MOVES
SOUTHEAST OUT OF THE PANHANDLE...A FEW THUNDERSTORMS MAY AFFECT
THE WESTERN COUNTIES. THUS HAVE LEFT LOW POPS THERE. OTHERWISE...
IT LOOKS LIKE A WARM AND DRY PERIOD WILL OCCUR THROUGH THE
WEEKEND. AS A SURFACE TROUGH DEVELOPS ACROSS THE NORTHERN AND
CENTRAL PLAINS...WE WILL SEE SOUTHERLY WINDS INCREASE WEDNESDAY
AND THURSDAY. AN UPPER LEVEL RIDGE WILL DEVELOP ACROSS THE SOUTHEASTERN
UNITED STATES FRIDAY INTO THE WEEKEND. AS LOW LEVEL MOISTURE
INCREASES...CAN NOT RULE OUT SOME ISOLATED AFTERNOON/EARLY EVENING
THUNDERSTORMS SUNDAY AND MONDAY...BUT RAIN CHANCES ARE NOT HIGH
ENOUGH TO MENTION YET.

58



&&


.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX  91  69  93  71  95 /  10  10   5  10  10
WACO, TX              93  67  95  71  95 /  20  10   5  10  10
PARIS, TX             85  62  89  67  88 /   5   5   5  10  10
DENTON, TX            91  68  93  71  95 /  10  10   5  10  10
MCKINNEY, TX          90  66  92  70  92 /  10  10   5  10  10
DALLAS, TX            92  70  93  71  94 /  10  10   5  10  10
TERRELL, TX           88  66  92  69  93 /  10  10   5  10  10
CORSICANA, TX         91  67  92  70  93 /  10  10   5  10  10
TEMPLE, TX            92  66  93  70  94 /  20   5   5  10   5
MINERAL WELLS, TX     91  65  94  68  97 /  20  10   5  10  10

&&

.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

 /






AREA FORECAST DISCUSSION

NWS BLACKSBURG VA

 1026 AM EDT TUE MAY 22 2012

.SYNOPSIS...
A COLD FRONT SLOWLY PUSHES EAST ACROSS THE AREA THIS AFTERNOON...AND
THEN TO THE COAST BY LATE WEDNESDAY. SHOWERS AND THUNDERSTORMS...WITH
SOME POTENTIALLY BRINGING HEAVY RAIN...WILL BE POSSIBLE THROUGH
THURSDAY. HIGH PRESSURE AND DRIER WEATHER WILL ARRIVE LATE IN THE
WEEK.
&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM EDT TUESDAY...

WEAK FRONT EDGING INTO THE FAR WESTERN SECTIONS THIS MORNING LOOKS
TO BE THE MAIN FOCUS FOR DEEPER AFTERNOON CONVECTION ESPCLY ACROSS
THE MOUNTAINS NEAR THE EDGE OF THE CLOUD CANOPY TO THE WEST ATTM.
LATEST MODIFIED MORNING RAOBS SHOW 1500-2K J/KG CAPES PROVIDED
ENOUGH HEATING THIS AFTERNOON UNDER LIGHT STEERING PER A MEAN
FLOW OF 6-10 KTS. THIS SHOULD AGAIN SPELL SLOW MOVING CLUSTERS OF
STORMS ESPCLY MOUNTAINS WITH A FEW OF THESE PERHAPS GOING SEVERE
WITH DOWNBURST POTENTIAL PER DECENT WINDEX VALUES...AND SOME HAIL
GIVEN LOW WET BULB VALUES OFF MORNING SOUNDINGS. HOWEVER WITH SUCH
A MID LEVEL CAP SEEN THIS MORNING MAY TAKE THINGS A LITTLE LONGER
TO DEVELOP WITH BETTER FOCUS LATER ON WEST AS THE UPPER LOW STARTS
TO LIFT NE ALONG THE SRN APPALACHIANS. THUS MAIN CHANGES WERE TO
SLOW DOWN ONSET OF CONVECTION THIS MORNING AND THEN INCREASE POPS
SOME WEST WHERE KEEPING HEAVY RAIN MENTION/WATCH IN PLACE. THIS
SUPPORTED BY EXPANSIVE COVERAGE OFF BOTH THE LATEST HRRR AND LOCAL
WRF MODELS AFTER MIDDAY INTO EARLY THIS EVENING. EXTENT OF TSRA
COVERAGE A BIT MORE IFFY E/SE GIVEN LESS SUPPORT AND MORE OUTFLOW
DRIVEN...BUT EXPECT HIGH CAPES AND EVENTUAL SPILLING OF WESTERN
CONVECTION TO SUPPORT LIKELY POPS THERE. RAISED HIGH TEMPS
SLIGHTLY ALONG THE BLUE RIDGE WHERE SHOULD SEE MORE SUN EARLY OTRW
70S WEST TO LOW 80S EAST APPEAR ON TRACK.

AS OF 615 AM EDT TUESDAY...

UPDATE TO DROP POPS SOME THIS MORNING GIVEN RADAR TRENDS. WILL
SEE INCREASE IN COVERAGE AGAIN OVER THE MTNS BY LATE MORNING.
DECREASED CLOUD COVERAGE EARLY AS WELL ESPECIALLY THE SRN CWA.

PREVIOUS DISCUSSION AT 355 AM...

ECHOES ON RADAR WEAKENING AS EXPECTED BUT NOT SURPRISED THAT
SHOWERS HAVE LINGERED ALL NIGHT...PER HIGHER THETA-E AIR AND
LINGERING BOUNDARIES AND UPPER SUPPORT. TODAY WILL BE ANOTHER
STORMY ONE FOR THE AREA AND EXPECT MORE COVERAGE OF SHOWERS AND
STORMS. GIVEN THE RAINFALL OVER THE MOUNTAINS THAT LAST FEW DAYS
AND LOWER FFG VALUES COMBINED WITH A PATTERN CONDUCIVE TO SLOW
MOVING STORMS AND HIGH PWATS...HAVE WENT AHEAD AN ISSUED A FLASH
FLOOD WATCH FOR AREAS ALONG AND WEST OF THE BLUE RIDGE.

THE FOCUS TODAY WILL BE ACROSS THE MOUNTAINS WHERE BEST UPPER
DIFFLUENCE IS EXPECTED WITH UPPER TROUGH. AT THE SFC...COLD FRONT
WILL BE EDGING EWD TO THE BLUE RIDGE BY EVENING WITH SEVERAL WEAK
LOWS MOVING ALONG IT. WITH EXTENSIVE CLOUD COVER...NOT EXPECT A
WIDESPREAD THREAT FOR SVR BUT WITH MOIST AIRMASS...AND COLDER AIR
ALOFT WITH THE UPPER TROUGH...WOULD NOT BE SURPRISED THAT SOME
STORMS BECOME STRONG TO SEVERE WITH ISOLATED LARGE HAIL/MICROBURST
THREAT. WINDS ALOFT ARE WEAK...SO WOULD HAVE TO BE ENOUGH RAIN
LOADING IN THE STORM TO BRING DAMAGING WINDS.

WILL HAVE HIGHER POPS THIS AFTERNOON WITH CATEGORICAL ACROSS THE
BLUE RIDGE AND WEST. WITH MOIST AIRMASS AND LESS SUN WILL SEE HIGHS
IN BETWEEN THE COOLER MET/WARMER MAV...ALTHOUGH COOLER MET MAY HAVE
A BETTER IDEA. THE LOCAL MOS IN BETWEEN THE TWO SEEMS TO BE A BETTER
CHOICE...GIVEN SOME POTENTIAL FOR SUN. WITH THAT IN MIND...HIGHS
WILL RANGE FROM THE LOWER 80S SOUTHEAST TO THE LOWER 70S IN THE
SOUTHWEST WHERE STORMS ARRIVE/DEVELOP SOONER.


TONIGHT...THE HEAVY RAIN THREAT SHOULD DIMINISH OVERNIGHT AS ONE
AREA OF LIFT PUSHES OUT OF THE AREA. HOWEVER...MODELS SOLUTIONS ARE
CONVERGING TOWARD ANOTHER ORGANIZED AREA OF SHOWERS/STORMS OVER SW
VA AFTER MIDNIGHT...SO IF TRENDS CONTINUE TO SHOW THIS...MAY HAVE TO
EXTEND THE FFA FURTHER IN TIME...AS IT RUNS TIL MIDNIGHT FOR NOW.
LOWS TONIGHT WILL BE MILD AGAIN WITH LOWER TO MID 60 EAST TO MID 50S
WEST.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 355 AM EDT TUESDAY...

NOT TOO MUCH CHANGES THIS PERIOD...WITH UPPER TROUGH LINGER OVER THE
AREA...AND SFC FRONT EAST OF THE FORECAST AREA. PATTERN STILL WILL
REMAIN CONDUCIVE FOR SHOWER/STORM DEVELOPMENT ESPECIALLY IN THE
AFTN. MODELS ARE CONVERGING AGAIN ON THE NORTHERN FORECAST AREA TO
SEE MORE RAINFALL...AND KEPT POPS IN THE LIKELY RANGE ACROSS THIS
AREA....WITH HIGH CHANCE SOUTH TO THE NC/VA COUNTIES. HIGHER PWATS
WILL RESIDE OVER THE ERN CWA. AGAIN LOOKING AT MOSTLY CLOUD SKIES
ALL DAY WHICH IS GOING TO LIMIT HEATING AND THE SVR THREAT SHOULD
STAY ISOLATED...WITH HAIL POSSIBLE GIVEN UPPER COOL POOL OVER NC.

EXPECT TO SEE POPS TAPER OFF THE LOW CHANCE TO LESS THAN 20 PERCENT
WEST OF THE BLUE RIDGE AFTER MIDNIGHT WED NIGHT PER UPPER LOW
SHIFTING EAST INTO THE VA PIEDMONT.

THURSDAY LOOKS DRIER...BUT ANOTHER UPPER TROUGH SHIFTS FROM THE
TENNESSEE VALLEY INTO GEORGIA AND UPPER FLOW AND
DIVERGENCE...COMBINED WITH MODEST INSTABILITY SHOULD LEAD TO MORE OF
A SCATTERING OF SHOWERS AND STORMS.

SHOWERS AND STORMS SHOULD START TO WEAKEN THURSDAY NIGHT WITH LOSS
OF HEATING.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 305 PM EDT MONDAY...

THE MEDIUM RANGE MODELS AND ENSEMBLES ARE IN GOOD AGREEMENT
BUILDING A STRONG UPPER RIDGE...FIRST OVER THE OHIO VALLEY...THEN
ELONGATING INTO THE MID-ATLANTIC REGION SUNDAY INTO MONDAY. THIS
WILL RESULT IN TEMPERATURES WELL ABOVE NORMAL AND LESS COVERAGE IN
PRECIPITATION.

ON FRIDAY...THE LINGERING UPPER LEVEL TROF FINALLY GETS PUSHED
NORTHEAST BY A SHORTWAVE MOVING THROUGH THE GREAT LAKES. WITH A
MOIST (GREATER THAN 1.5 PWATS) AND UNSTABLE AIR MASS IN PLACE AND
WEAK LOW LEVEL CONVERGENCE AND THE SFC...WIDELY SCATTERED
THUNDERSTORMS WILL AGAIN BE POSSIBLE.

THE COVERAGE OF SHOWERS AND STORMS SHOULD DIMINISH THROUGH THE
HOLIDAY WEEKEND AS THE UPPER RIDGE BUILDS. HOWEVER...WEAK...BUT
FAIRLY DEEP EAST/SOUTHEAST UPSLOPE LOW LEVEL FLOW MAY BE ABOVE TO
OVERCOME WARMING MID LEVEL TEMPS/RISING HEIGHTS TO INITIATE ISOLATED
TO WIDELY SCT STORMS ALONG THE BLUE RIDGE.

LEARNED TOWARD THE WARMER MEX GUIDANCE FOR TEMPS THROUGH THE LONG
TERM PERIOD...WITH FORECAST HIGHS NEARING RECORDS FOR BLF.

&&

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
AS OF 715 AM EDT TUESDAY...

ANY FOG/LOWER CIGS WILL BE LIFTING SOON AND SHOULD SEE MAINLY
VFR CONDITIONS TODAY OUTSIDE OF STORMS. THE STORMS SHOULD FORM
AGAIN BY MIDDAY OVER THE MOUNTAINS WITH SLOW MOVEMENT...THEN
STORMS WILL BE FORMING ALONG/EAST OF THE BLUE RIDGE TOWARD 18Z-21Z.

THE BEST COVERAGE TODAY SHOULD BE ALONG/WEST OF THE BLUE
RIDGE...AND WILL SEE HEAVY RAINS FROM THESE STORMS. GIVEN THE
NATURE OF THIS PATTERN...KEPT TAFS LOW END VFR.

WILL STILL SEE SOME COVERAGE OF CONVECTION HEADING INTO THE
EVENING BUT SHOULD BE LESS...SO TOOK IT ALL OUT OF TAFS. AGAIN
WILL BE A NIGHT SIMILAR TO THIS MORNING WHERE CIGS/VSBYS COULD
FLUCTUATE BETWEEN LIFR TO VFR AT TIMES...SO WENT TOWARD MIDDLE
ROUTE OF IFR...MAINLY WITH FOG INSTEAD OF LOWER CIGS.

WEDNESDAY WILL BE A REPEAT OF TODAY WITH MOST COVERAGE OF STORMS
SHIFTING NORTH OF A LINE FROM BLF-LYH. MAINLY VFR AFTER MORNING
FOG/LOWER CLOUDS EXCEPT IN HEAVIER TSRA.

LOOKING AT THE PATTERN SHIFTING TOWARD THE END OF THE WEEK...AND
UNTIL FRIDAY SHOULD SEE NIGHTTIME THREAT OF LOWER CIGS/FOG AND
DAYTIME THUNDER. BY FRIDAY WILL SEE HIGH PRESSURE WORKING IN TO
BRING VFR WX...AND TEMPERATURES HEAT UP. NIGHLTY FOG IN THE
VALLEYS BCB/LWB A GOOD POSSIBILITY GIVEN THE GROUND SHOULD BE
MOIST...WITH LITTLE WIND.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH THROUGH THIS EVENING FOR VAZ007-009>020-
     022>024.
NC...FLASH FLOOD WATCH THROUGH THIS EVENING FOR NCZ001-002-018.
WV...FLASH FLOOD WATCH THROUGH THIS EVENING FOR WVZ042>045.

&&

$$
SYNOPSIS...PW/WP
NEAR TERM...JH/WP
SHORT TERM...PH/WP
LONG TERM...PH
AVIATION...WP








AREA FORECAST DISCUSSION

NWS TAUNTON MA

 122 PM EDT TUE MAY 22 2012

.SYNOPSIS...
LOW PRESSURE WILL PASS EAST OF CAPE COD THIS AFTERNOON.
SOUTHEASTERLY FLOW OVER SOUTHERN NEW ENGLAND LATE THIS WEEK MAY
RESULT IN SHOWERS AND THUNDERSTORMS. CHANCE FOR STORMS INCREASES
SATURDAY AS A COLD FRONT APPROACHES THE AREA.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE...THREE BANDS OF SHOWERS ON THE RADAR. ONE IS
ACROSS SOUTHERN NH AND WESTERN MASS...THE SECOND IS SOUTHEAST MASS
AND RI AND EASTERN CT...THE THIRD IS MOVING INTO THE ISLANDS.
THESE ARE SLIDING NORTH-NORTHWEST. THE UPDATE GOES WITH LIKELY TO
CATEGORICAL POPS ROUGHLY DRAWN TO MIRROR THESE BANDS. POPS
DIMINISH TO CHANCE DURING THE AFTERNOON AS THE OFFSHORE LOW MOVES
PAST. WINDS HAVE BEEN BLENDED WITH THE LATEST HRRR GUIDANCE. BASIC
IDEA OF THE FORECAST REMAINS INTACT.

ORIGINAL DISCUSSION...
MID LEVEL CIRCULATION EAST OF NJ COAST WITH TROWAL SIGNATURE IN
PLACE TO THE NORTH ACROSS NEW ENG. BANDS OF MAINLY LIGHT SHOWERS
ARE LIFTING NORTH ACROSS SNE EARLY THIS MORNING. SFC REFLECTION IN
THE FORM OF A WEAK WAVE IS FORECAST TO TRACK NE AND PASS E OF CAPE
COD TODAY. WEAK EASTERLY LOW LEVEL JET ALONG WITH SOME INSTABILITY
JUST OFFSHORE MAY HELP TO ENHANCE SHOWERS OVER THE CAPE/ISLANDS
THROUGH THE MORNING. OTHERWISE...WILL CONTINUE WITH CHC SHOWERS AS
MID LEVEL SHORTWAVE LIFTS NWD ACROSS THE REGION. EXPECT LOW CLOUDS
TO PERSIST TODAY GIVEN ABUNDANT LOW LEVEL MOISTURE BUT IMPROVING
VSBYS DURING THE DAY. USED A BLEND OF TRADITIONAL MOS GUIDANCE AND
BIAS CORRECTED GRIDS FOR MAX TEMPS. COOLEST TEMPS WILL BE ACROSS E
COASTAL MA WITH MILDEST READINGS IN THE CT VALLEY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
TONIGHT...
MID LEVEL SHORTWAVE AND WEAK SFC WAVE EXIT TO THE EAST WITH WEAK
SFC RIDGING DEVELOPING SO EXPECT MOSTLY DRY CONDITIONS. STILL CANT
RULE OUT A BRIEF SHOWER OR PATCHY DRIZZLE GIVEN THE MOISTURE IN
PLACE SO HAVE SLIGHT CHC POPS...BUT MOST OF THE NIGHT SHOULD BE
DRY.

WEDNESDAY...
NEXT MID LEVEL LOW WILL MOVE TO THE SE US AND SOUTHERN MID ATLC
REGION WITH RIDGING DEVELOPING TO THE NORTH INTO NEW ENG.
HOWEVER...MODELS INDICATE MARGINAL SFC INSTABILITY DEVELOPING AS
DEEP LAYER MOISTURE DECREASES A BIT WHICH MAY ALLOW FOR SOME
BREAKS OF SUNSHINE DEVELOPING...ESPECIALLY INTERIOR. FORECAST
CAPES 500-1000 J/KG AND LI/S -2 TO -3C SO WILL HAVE CHC
SHOWERS/TSTMS. SVR WEATHER NOT ANTICIPATED GIVEN WEAK WIND FIELD AND
MARGINAL MID LEVEL LAPSE RATES...BUT THIS WILL LEAD TO LOCALIZED
HEAVY RAINFALL BEING A THREAT AS PWATS NEAR 1.5".

USED A BLEND OF MAV/MET GUIDANCE FOR MAX TEMPS...MAINLY 75 TO 80
DEGREES...BUT COOLER ALONG THE COAST WHERE SEABREEZES ARE
EXPECTED.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
* UNSETTLED WEATHER CONTINUES THROUGH THE END OF THE WEEK
  * TEMPERATURES ON A GRADUAL WARMING TREND THROUGH EARLY NEXT WEEK

OVERVIEW...
AGREEMENT AMONGST THE 00Z MODELS IS PRETTY DISMAL IN REGARDS TO
TIMING.  THE GFS IS 12 TO 24 HOURS FASTER THAN THE ECMWF WITH MOST
FEATURES THROUGH THE PERIOD.  OVERALL...AN UPPER RIDGE MOVES
OFFSHORE THURSDAY FOLLOWED BY AN UPPER TROUGH MOVING ACROSS SOUTHERN
NEW ENGLAND.  ALL THIS OCCURS WITH HIGH PRESSURE OVER MAINE AND NOVA
SCOTIA...PROVIDING A MOIST SOUTHEASTERLY FLOW.  LOW PRESSURE MOVING
THROUGH QUEBEC OVER THE WEEKEND BRINGS A COLD FRONT THROUGH SOUTHERN
NEW ENGLAND SATURDAY.  THERE ARE A FEW MORE DISCREPANCIES IN THE
MODELS SUNDAY AND MONDAY.  A WARM FRONT WILL ADVANCE NORTHWARD
THROUGH THE REGION SOMETIME DURING THIS PERIOD...RESULTING IN WARMER
TEMPERATURES AND ANOTHER SHOT OF RAIN.

DETAILS...
WEDNESDAY NIGHT INTO THURSDAY...CLOUDY AND UNSETTLED WEATHER IS
EXPECTED THROUGH THIS PERIOD WITH THE BEST SHOT OF SHOWERS AND/OR
THUNDERSTORMS ON THURSDAY AFTERNOON.  DECENT MID LEVEL LAPSE RATES
AND CONVECTIVE PARAMETERS INDICATE AN UNSTABLE ATMOSPHERE SO WILL
KEEP CHANCE OF THUNDER IN THE GRIDS FOR THURSDAY AFTERNOON AND
EVENING.  USED A BLEND OF MOS FOR TEMPERATURES YIELDING TEMPERATURES
SLIGHTLY ABOVE NORMAL IN THE MID TO UPPER 70S.  WITH DEWPOINTS WELL
INTO THE 50S AND EVEN INTO THE LOW 60S AT TIMES OVERNIGHT AND MOIST
GROUND...EXPECT FOG TO DEVELOP OVERNIGHT.

FRIDAY...SOUTHWEST SURFACE FLOW AHEAD OF A COLD FRONT TRAILING A LOW
PRESSURE IN QUEBEC WILL YIELD ANOTHER DAY OF ABOVE NORMAL
TEMPERATURES.  ADDITIONALLY...SOUTHWEST WINDS WILL BRING IN MOISTURE
AND HIGHER DEWPOINTS.  SHOWERS ARE LIKELY TO FORM DIURNALLY WITH
MODELS HINTING AT A POTENTIAL FOR THUNDER.  SOMEWHAT UNCERTAIN AT
THIS POINT SO HAVE LEFT THUNDER OUT OF THE GRIDS FOR THE TIME
BEING.  FOG IS POSSIBLE AGAIN DURING THE OVERNIGHT PERIOD.

SATURDAY...LOW PRESSURE MAKES ITS WAY ACROSS QUEBEC BRINGING A COLD
FRONT ACROSS SOUTHERN NEW ENGLAND AT SOME POINT SATURDAY.  THERE IS
SOME DIFFERENCE BETWEEN THE MODELS ON TIMING FOR THIS.  AHEAD OF THE
FRONT...MID LEVEL LAPSE RATES INCREASE AND SOUTHWEST FLOW AT THE
SURFACE WILL BRING IN HIGHER DEWPOINTS.  THIS WILL LIKELY RESULT IN
WIDESPREAD SHOWERS.  AGAIN...THUNDER IS A POSSIBILITY WITH THESE
SHOWERS...BUT THIS BEING DAY 5 AND THERE REMAINING SOME UNCERTAINTY
HERE...WILL LEAVE OUT OF THE GRIDS.

SUNDAY AND MONDAY...MOST MODEL DISCREPANCIES EXIST HERE.  THERE IS
SOME INDICATION OF GRADUALLY WARMING TEMPERATURES THROUGH THE
HOLIDAY WEEKEND.  ECMWF SHOWS A SLIGHT COOL OFF SUNDAY BUT
REBOUNDING MONDAY WHILE THE GFS HAS TEMPS WARMING THROUGH THIS
PERIOD.  A WARM FRONT WILL MOVE THROUGH THE REGION DURING THIS TIME
BRINGING WARM...MOIST AIR INTO THE AREA AND PRODUCING SHOWERS AND
POSSIBLY THUNDERSTORMS.

&&

.AVIATION /17Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
  LOW...LESS THAN 30 PERCENT
  MODERATE...30 PERCENT TO 60 PERCENT
  HIGH...GREATER THAN 60 PERCENT

OVERVIEW...
MODERATE CONFIDENCE IN TAFS. PERSISTENT N/NE FLOW WILL KEEP LOW
CIGS LOCKED IN THROUGH WED MORNING AND AREAS OF FOG EXPECTED TO
BECOME WIDESPREAD AGAIN THIS EVENING. CIGS WILL BE SLOW TO IMPROVE
WED BUT AM CONFIDENT ON IMPROVEMENT TO VFR AROUND MIDDAY...EXCEPT
ON OUTER CAPE COD AND KACK WHERE LOW CIGS WILL PROBABLY REMAIN ALL
DAY. WEAK GRADIENT WILL BRING RETURN OF LOW CLOUDS/FOG WED NIGHT...
ESPECIALLY NEAR COAST.

KBOS TAF...MODERATE CONFIDENCE. TIMING OF LOWEST CONDITIONS
TONIGHT MAY BE A FEW HOURS TOO FAST. HIGHER CONFIDENCE ON TIMING
OF IMPROVEMENT WED.

KBDL TAF...MODERATE CONFIDENCE. TIMING OF IFR CIGS MAY BE A FEW
HOURS TOO FAST TONIGHT. HIGHER CONFIDENCE ON TIMING OF IMPROVEMENT
WED.

OUTLOOK...THURSDAY THOUGH SATURDAY...

THURSDAY THROUGH SATURDAY...LOW TO MODERATE CONFIDENCE.  DAYTIME
GENERALLY VFR WITH PERIODS OF MVFR IN SHOWERS AND POSSIBLE TSRA.
NIGHTTIME MVFR WITH PERIODS OF IFR IN FOG.

&&

.MARINE...
MODERATE TO HIGH CONFIDENCE THROUGH WEDNESDAY. WINDS WILL REMAIN
WELL BELOW SCA THRESHOLDS...BUT INCREASING SE SWELL WILL RESULT IN
SEAS BUILDING TO 5-7 FT OVER THE S COASTAL WATERS. WNAWAVE
GUIDANCE HAS BEEN OVERDONE ON SEAS SO WE USED MORE CONSERVATIVE
SWAN NAM. SCA FOR HAZARDOUS SEAS WILL CONTINUE.

OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...

SEAS REMAIN BELOW 5 FEET THROUGH THE PERIOD WITH HIGH PRESSURE OVER
MAINE AND THE MARITIMES.  SIMILARLY WINDS WILL REMAIN GENERALLY OUT
OF THE SOUTH AND BELOW 25 KTS.  HIGH CONFIDENCE IN FOG REDUCING
VISIBILITIES AT TIMES...MOSTLY DURING THE OVERNIGHT PERIODS.
SHOWERS AND THUNDERSTORMS ARE A LOW PROBABILITY EACH AFTERNOON AND
EVENING.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
     WEDNESDAY FOR ANZ235-237-254>256.

&&

$$
SYNOPSIS...KJC
NEAR TERM...WTB/KJC
SHORT TERM...KJC
LONG TERM...RLG
AVIATION...JWD
MARINE...KJC/RLG








AREA FORECAST DISCUSSION

NWS MOUNT HOLLY NJ

 611 PM EDT TUE MAY 22 2012

.SYNOPSIS...
A LOW PRESSURE SYSTEM SOUTHEAST OF CAPE COD WILL DRIFT NORTHEAST
TONIGHT AND WEDNESDAY. A HIGH PRESSURE SYSTEM WILL THEN BUILD IN
BEHIND IT OVER THE CANADIAN MARITIMES ON THURSDAY AND SLOWLY SINK
SOUTHWEST OVER THE MEMORIAL DAY WEEKEND AND BECOME ESTABLISHED OFF
THE SOUTHEAST UNITED STATES COAST. A BACKDOOR COLD FRONT WILL TRY
TO SAG SOUTH INTO THE AREA ABOUT SUNDAY BEFORE RETREATING NORTH ON
MEMORIAL DAY. A FRONT DOOR COLD FRONT WILL APPROACH THE AREA FROM
THE GREAT LAKES ON TUESDAY.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
DESPITE BREAKS IN THE CLOUDS THIS AFTERNOON...THE SCATTERED SHOWER
ACTIVITY HAS BEEN SLOW TO EVOLVE LATE THIS AFTERNOON. IN FACT...TOPS
HAVE NOT GOTTEN TO MINUS 20 CELSIUS YET...AND THIS WOULD SEEM TO
EXPLAIN THE LACK OF LIGHTNING DATA TO THIS POINT. THE LOSS OF
DAYTIME HEATING SOON PROBABLY MEANS THE WINDOW OF OPPORTUNITY FOR
THUNDER WITH THE SCATTERED SHOWERS DEVELOPING NOW IS CLOSING...AND
COULD BE REMOVED FROM NORTHERN ZONES BEFORE 900 PM.

THE LATEST HRRR RUN IS TRYING TO DEVELOP A BROKEN LINE OF
THUNDERSTORMS IN THE BEST INSTABILITY. THIS LIES ACROSS WEST CENTRAL
PENNSYLVANIA (WHERE THE SUNSHINE HAD A BETTER CHANCE TO
DESTABILIZE THE AIRMASS. THE IN SITU BULK SHEAR PROFILE IS NOT
THAT IMPRESSIVE...AND DOES NOT APPEAR TO GET ANY BETTER INTO THE
LATER EVENING HOURS. WHILE THERE IS SOME ACTIVITY NOW IN THE AXIS
OF BEST INSTABILITY...IT IS UNCLEAR JUST HOW MUCH OF THIS ACTIVITY
SURVIVES TO THE LEHIGH VALLEY AFTER 800 PM.

FOR NOW...WILL LEAVE THE MENTION OF THUNDER IN DEFERENCE TO THE
ACTIVITY TO THE WEST. HOWEVER...IF IT DOES NOT GET BETTER
ORGANIZED AS IT MOVES EAST...IT COULD BE REMOVED FROM THE FORECAST
LATER TONIGHT.

THE NEXT FORECAST PROBLEM FOR TONIGHT IS THE LOW CLOUDS AND FOG.
THE LOW CLOUDS DID BREAK THIS AFTERNOON...AND PATCHES ARE TRYING
TO REFORM EARLY THIS EVENING. NAM MODEL SOUNDINGS SHOW THAT THE
REDEVELOPMENT OF STRATUS COULD TAKE SOME TIME...ESPECIALLY WEST OF
THE DELAWARE RIVER. BASED ON THE CURRENT CLOUD COVER AND THE NAM
MODEL SOUNDINGS...THE TIMING OF THE STRATUS REAPPEARANCE HAS BEEN
PUSHED BACK A BIT.

STATISTICAL GUIDANCE SUGGESTS THAT TONIGHT COULD END UP BEING A
A BETTER SETUP FOR AREAS OF FOG (MOIST LOW LEVELS...HIGH PRESSURE
TO THE NORTHEAST). HOWEVER...NAM MODEL SOUNDINGS SUGGEST THE THE
LOW LEVEL HYDROLAPSE RATES DO NOT BECOME FAVORABLE FOR UNTIL LATER
TONIGHT...AND FOR A SHORTER TIME THAT THE MOS GUIDANCE WOULD
INDICATE. AREAS OF FOG WAS LEFT IN THE FORECAST...AND TRENDS WILL
BE WATCHED TO LOOK FOR POTENTIAL FOR DENSE FOG LATER TONIGHT.

FOR THE MOST PART...TEMPERATURES AND WINDS APPEAR TO BE ON TRACK
FOR THE OVERNIGHT.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
EXPECT PERIODS OF SHOWERS AND POSSIBLY THUNDERSTORMS DURG THE AFTN
AND THEY MAY BE MORE WIDESPREAD THAN TODAY ESPECIALLY IF WE GET MORE
BREAKS IN THE CLOUDS, BUT DON`T SEE ANY SIGNIFICANT FORCING
MECHANISMS.  GUID TEMPS LOOK REASONABLE ONCE AGAIN.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
THE WRF-NMMB INITIALIZATION WAS BETTER THAN THE GFS OFF OF THE 12Z
SOUNDINGS AND THE FORMER WAS GIVEN MORE WEIGHT THAN AVERAGE TODAY.
BTW TODAY IS THE FIRST DAY OF THE NEW GFS. IN THE BIG PICTURE, NO
CHANGES TO OUR THINKING WITH MAINLY DIURNALLY DRIVEN LOCALIZED HEAVY
RAIN CONVECTION INTO FRIDAY. THEN MODEL UNCERTAINTIES AS TO THE
BACKDOOR ON THE WEEKEND WITH THE TREND TOWARD WARMER AND MORE
HUMID WEATHER INCORPORATED.

THERE SHOULD BE A DIURNAL DOWNTREND IN THE CONVECTION ON WEDNESDAY
EVENING AS FORECAST CAPES AND LI(S) DECREASE. WE DID SHOW AN UPTICK
IN POPS LATER AT NIGHT AS THE SHORT WAVE ASSOCIATED WITH THE CLOSING
SERN CONUS LOW COMES CLOSE TO THE AREA. BOTH THE GFS AND WRF-NMMB DO
SHOW SOME WEAK SFC BASED INSTABILITY AS THIS FEATURE SLIDES BY AND
WE MENTION SOME THUNDER LATE. GIVEN THE CONTINUED UPTICK IN DEW
POINTS, WE MAINTAINED THE MENTION OF PATCHY FOG LATE. A STAT
GUIDANCE COMPROMISE WAS USED FOR MINS.

ON THURSDAY, WE LEANED MORE TOWARD THE WRF-NMMB SOLUTION OF GIVING
THE CANADIAN MARITIMES HIGH A BIT MORE OF A BITE AND SHELTERING OF
OUR CWA FROM CONVECTION. IN REALITY GFS MOS SUPPORTS THE WRF-NMMB
SFC FEATURES MORE SO THAN THE GFS ITSELF. BOTH WOULD FAVOR MORE
ACTIVITY WEST VS EAST. CONCEIVABLY BEING RIGHT FOR THE WRONG
REASON, THE GFS BRINGS IN DRY AIR ALOFT IN THE EAST DURING THE
DAY ON THURSDAY WHICH WOULD MAKE IT HARDER FOR CONVECTION TO
OCCUR. WITHOUT ANY ORGANIZED TRIGGER WITH THE AFOREMENTIONED SHORT
WAVE MOVING FARTHER OFFSHORE IN THE MORNING, KEPT POPS AS CHANCE.
GIVEN MORE OF AN ONSHORE INFLUENCE FROM THE SFC HIGH AND HOW LONG
WILL IT TAKE TO CLEAR LOW CLOUDS, WE LEANED MAX TEMPS MUCH CLOSER TO
THE LOWER NAM MOS THAN GFS MOS.

WASH, RINSE, REPEAT ON THURSDAY NIGHT. BUT, WITHOUT A LATE SHORT
WAVE, WE DROPPED POPS AS THE NIGHT PROGRESSES AND REMOVED THE
MENTION OF THUNDER. THE WRF-NMMB SOLUTION SUPPORTS STRATUS AT THE
LEAST AND A SUGGESTION OF DRIZZLE AT THE MOST AS THE .01 PCPN
FIELD BOOMS LATE AT NIGHT. FOR NOW WE WENT THE PATCHY FOG ROUTE
AND ACCEPTED THE STAT GUIDANCE MINS.

ON FRIDAY, THE MODELS AGREE ON A SLIGHTLY MORE EAST PUSH IN THE
INSTABILITY AXIS, MAYBE INTO THE DELAWARE VALLEY. OTHER THAN
MESOSCALE FEATURES, I.E. DIFFERENTIAL HEATING, OROGRAPHIC LIFTING,
MAYBE SEA OR BAY BREEZES, NOT MUCH ORGANIZATIONAL ACTIVITY EXPECTED
AGAIN. POPS WERE AGAIN KEPT BELOW LIKELY. WE STILL PREFER MORE OF A
MODIFIED MARINE INFLUENCE FROM OUR SURFACE HIGH TO THE EAST THAN THE
GFS SHOWED AND WE THUS KEPT MAX TEMPS BLO MEX MOS.

BOTH THE GFS AND WRF-NMMB DID SHOW AN AXIS OF HIGHER INSTABILITY
WORKING ITS WAY INTO WESTERN PA DURING THE DAY ON FRIDAY. IF THE
CONVECTION COULD MAINTAIN ITSELF, IT WOULD GET INTO OUR CWA BEFORE
RUNNING OUT OF GAS ON FRIDAY NIGHT. WE DID UP POPS SLIGHTLY.

THERE REMAINS SOME UNCERTAINTY AS TO HOW SOUTH WILL THE BACKDOOR
FRONT GET OVER THE WEEKEND. RIGHT NOW IT APPEARS TO BE A DIFFERENCE
BETWEEN WARM WEATHER AND SOME TYPICAL SUMMERTIME CONVECTION AROUND
BECAUSE OF THE LINGERING FRONT, OR A COUPLE OF WARM SECTOR DAYS WITH
HIGH TEMPERATURES REACHING THE 90S ON THE COASTAL PLAIN AWAY FROM
THE OCEAN. THE MODELS CONTINUE TO GO BACK AND FORTH WITH THIS
SCENARIO. MORE CONSENSUS ODDLY ABOUT HOT WEATHER ON MONDAY AND
TUESDAY. WE NUDGED MAX TEMPS UPWARD WITH THIS PACKAGE AND
MAINTAINED LOW POPS BECAUSE OF THE UNCERTAINTY OF THE FRONTAL
POSITION.

&&

.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

CONDS HAVE IMPROVED TO MVFR AND EVEN VFR IN SOME LOCATIONS AS LATEST
SATELLITE IMAGERY SHOWED THE CLOUDS HAVE THINNED.  EXPECT THESE
TRENDS TO CONTINUE INTO THE EARLY EVENING BEFORE WE GET A REPEAT
PERFORMANCE ONCE AGAIN.  CLOUDS WILL LOWER AND THICKEN AND EVERYONE
WILL BE MVFR/IFR AND EVEN LIFR DURG THE OVERNIGHT AND EARLY MORNING
HOURS BEFORE SOME IMPROVEMENT AGAIN DURG WEDNESDAY.

THE WIND SHOULD BE LIGHT AND GENLY FROM THE E AR SE.

OUTLOOK...
WEDNESDAY NIGHT THROUGH FRIDAY...IFR CONDS EACH NIGHT AND EARLY
EACH DAY IN STRATUS AND/OR FOG BECOMING VFR IN THE AFTN. LOCAL IFR
CONDS IN SHOWERS OR TSTMS. OUTLOOKING LESS COVERAGE AND DURATION
OF IFR AND MVFR CONDITIONS ON FRIDAY THAN THURSDAY.

SATURDAY AND SUNDAY...POSSIBLY SOME MVFR OR IFR STRATUS OR FOG EARLY
OTHERWISE VFR. ISOLATED THUNDERSTORMS POSSIBLE MAINLY LATE EACH DAY
WITH MVFR CONDITIONS.

&&

.MARINE...
THE PROLONGED ELY TO EVENTUALLY SELY WILL CONTINUE AND SEAS HAVE
BEEN ABOVE SCA FOR MOST OF THE DAY.  THIS WILL CONTINUE THROUGH THE
NIGHT, BUT LTST GUIDANCE INDICATES THE SRN WATERS WILL RETREAT BELOW
SCA VALUES ON WEDNESDAY.  ACRS THE N, THINGS MAY LINGER LONGER.
HOWEVER, FOR NOW, WILL LET THE PREV ISSUED SCA CONTINUE WITH NO
CHANGES, BUT IT MAY NEED TO BE EXTENDED FOR A FEW HOURS, ESPECIALLY
ACRS THE N.

OUTLOOK...
WE ARE NOT EXPECTING SMALL CRAFT ADVISORY CONDITIONS TO OCCUR
THROUGHOUT THE OUTLOOK PERIOD AS THE ONSHORE FLOW FROM THE CANADIAN
MARITIMES SHOULD NOT BE THAT STRONG AND EVEN IF WE GET A BACKDOOR
FRONT, WINDS ARE NOT EXPECTED TO BE STRONG EITHER. THE GREATER
MARINE CONCERNS WILL BE FOG AS DEW POINTS SHOULD RISE ABOVE THE
WATER TEMPS. THIS MAY THE CASE EVERY MORNING INTO SUNDAY. ALSO
THERE MAY BE STRONGER WINDS NEAR THUNDERSTORMS, ALTHOUGH THE
GREATEST INSTABILITY IS EXPECTED TO BE WEST OF THE COASTAL WATERS.

&&

.HYDROLOGY...
THERE WILL PROBABLY BE NARROW SWATHS OF 72 HOUR TOTAL 1-3 INCH RFALL
BETWEEN TONIGHT AND FRIDAY...MAINLY IN E PA AND POSSIBLY NNJ. PWATS
THIS WEEK AROUND 1.4 INCHES INCREASE TO AT LEAST 1.75 INCHES THIS
WEEKEND.

&&

.RIP CURRENTS...
THE SOUTHEAST SWELL SHOULD BE DROPPING TONIGHT INTO WEDNESDAY.
WHILE THE PERIOD REMAINS FAIRLY LONG (NEAR 9 SECONDS)...THE SURF
HEIGHT SHOULD COME DOWN AS WELL. BASED ON THE ABOVE...OUR LOCAL
STUDY SHOWS THE NEW JERSEY COAST COMING IN AT MODERATE...AND THE
DELAWARE COAST COMING IN WITH A LOW RISK OF RIP CURRENTS
WEDNESDAY. THE ABOVE WILL BE REFLECTED IN THE EVENING SURF ZONE
FORECAST FOR WEDNESDAY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT
     WEDNESDAY FOR ANZ450>455.

&&

$$

SYNOPSIS...GIGI
NEAR TERM...HAYES/NIERENBERG
SHORT TERM...NIERENBERG
LONG TERM...GIGI/99
AVIATION...DRAG/GIGI/NIERENBERG
MARINE...GIGI/NIERENBERG
HYDROLOGY...DRAG
RIP CURRENTS...HAYES







AREA FORECAST DISCUSSION

NWS DODGE CITY KS

 234 PM CDT TUE MAY 22 2012

...UPDATE TO LONG TERM DISCUSSION...

.SYNOPSIS...
ISSUED AT 1218 PM CDT TUE MAY 22 2012

A 500MB UPPER TROUGH WAS LOCATED NEAR THE SOUTHWEST COAST OF BRITISH
COLUMBIA AND NORTHWEST WASHINGTON AT 12Z TUESDAY. A 120-140KT
UPPER LEVEL JET WAS PLACE NEAR AND JUST SOUTHWEST OF THE BASE OF
THIS UPPER TROUGH. 90-110 METER HEIGHT FALLS WERE OBSERVED ACROSS
EASTERN IDAHO AND WESTERN MONTANA. A WESTERLY FLOW EXTENDED
ACROSS THE ROCKIES INTO THE WESTERN HIGH PLAINS WITH +12 TO +13C
700MB TEMPERATURES STRETCHING FROM EASTERN WYOMING/WESTERN
NEBRASKA INTO NORTHEAST NEW MEXICO. UNDER THESE WARM 700MB
TEMPERATURES AT THE SURFACE THERE WAS A TROUGH OF LOW PRESSURE
ACROSS WESTERN NEBRASKA AND EXTREME EASTERN COLORADO/FAR WESTERN
KANSAS.

&&

.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 128 PM CDT TUE MAY 22 2012

RAP, NAM AND HRRR PLACE THE SURFACE TROUGH OF LOW PRESSURE NEAR
THE COLORADO BORDER THIS EVENING. MODEL SOUNDINGS AT 00Z
WEDNESDAYS IN THIS AREA INDICATING LITTLE TO NO CIN WITH A
TEMPERATURES DRY ADIABATIC UP TO AROUND THE 600MB LEVEL WHERE SOME
MOISTURE IS PRESENT. ALSO OBSERVING SOME INSTABILITY PRESENT AS
WELL SO AM UNABLE TO COMPLETELY RULE OUT A EARLY EVENING
THUNDERSTORM DEVELOPING NEAR THE COLORADO BORDER EARLY THIS
EVENING. RAP AND HRRR DO HINT AT A FEW STORMS DEVELOPING AFTER 22Z
NEAR THE ELKHART WHERE THE BETTER INSTABILITY ARE FORECAST TO BE
LOCATED. WITH THIS IN MIND THE PREVIOUS PRECIPITATION FORECAST FOR
EXTREME SOUTHWEST KANSAS STILL APPEARS TO BE ON TRACK. ALSO BASED
ON THE INVERTED V TYPE OF SOUNDINGS IT DOES APPEAR THAT STRONG
WINDS UP TO 60 OR 70 MPH WILL BE THE MAIN HAZARD. ANY STORM THAT
DOES DEVELOP EARLY THIS EVENING IS EXPECTED TO END BEFORE MIDNIGHT
BUT MAY MOVE AS FAR EAST AS LIBERAL IF THESE A COLD POOL CAN BE
DEVELOPED FROM STORMS. AFTER MIDNIGHT SOUTH WINDS OF 15 TO 25 MPH
ARE EXPECTED TO CONTINUE AND BASED ON TEMPERATURES EARLIER THIS
MORNING WILL FAVOR OVERNIGHT LOWS AROUND 5F WARMER THAN GUIDANCE.

ON WEDNESDAY A SURFACE TROUGH/DRYLINE WILL SLIDE EAST INTO
WESTERN KANSAS DURING THE DAY AS A COLD FRONT DROPS SOUTH INTO
NORTHWEST KANSAS BY LATE MORNING. THE COLD FRONT IS EXPECTED TO BE
LOCATED FROM WEST CENTRAL KANSAS AND NORTH CENTRAL KANSAS BY THE
MID AFTERNOON AS WARM MID LEVEL TEMPERATURES SPREADS EAST ACROSS
SOUTHWEST KANSAS. MODEL SOUNDINGS INDICATING ANOTHER DAY OF GOOD
MIXING AND BASED ON MODEL SOUNDINGS AT 00Z THURSDAY IT CURRENTLY
APPEARS HIGHS AROUND 100 DEGREES WILL STILL BE POSSIBLE WEST OF
THE DRYLINE. EAST OF THE DRYLINE AND NEAR THE COLD FRONT THE HIGHS
WILL BE SLIGHTLY COOLER AND RANGE FROM THE LOW TO MID 90S.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 234 PM CDT TUE MAY 22 2012

WEDNESDAY NIGHT:

A FRONTAL BOUNDARY COULD BE THE IMPETUS FOR CONVECTION WEDNESDAY NIGHT
MAINLY ACROSS THE INTERSTATE 70 CORRIDOR. MARGINAL SURFACE DEWPOINTS
IN THE 50S DEG F AND VERY WARM MAXIMUM TEMPERATURES IN THE 90S DEG F
ACROSS CENTRAL KANSAS WILL CONTRIBUTE TO 1500 TO 2500 J/KG OF SBCAPE.
AN 850 HPA THETA-E AXIS WILL ALSO EXIST ACROSS WEST CENTRAL KANSAS WITH
BROAD SOUTHWESTERLY FLOW ALOFT WHICH POINT TO FAVORABLE CONDITIONS FOR
CONVECTION. SEVERE WEATHER CANNOT BE RULED OUT WITH 40 TO 50 KT OF BULK
0 TO 6 KM SHEAR.

THURSDAY:

A BROAD 500 HPA TROUGH IS EXPECTED FROM THE PACIFIC NORTHWEST TOWARDS
THE NORTHERN PLAINS. ANOTHER VORTMAX MOVING DOWNSTREAM WILL USHER
IN A COLD FRONT EXTENDING FROM THE UPPER MIDWEST TO SOMEWHERE IN
KANSAS. I SAY SOMEWHERE BECAUSE THERE IS PRETTY LARGE SPATIAL DIFFERENCES
BETWEEN THE ECMWF/GFS. THIS IS PARTICULARLY TRUE WHEN THE FRONT RETURNS
AS A WARM FRONT LATE THURSDAY. DECIDED TO TAKE THE MORE AGGRESSIVE
ECMWF APPROACH WITH THE NORTHWARD PROGRESSION OF THIS WARM FRONT. SOUTH
OF THIS FRONT, LOW LEVEL TEMPS ARE EXPECTED TO BE VERY WARM (30 DEG
C @ 850 HPA/15 DEG C @ 700 HPA), SO HAVE KEPT LOWER 90S DEG F TOWARDS
THE OKLAHOMA BORDER AND "COOLER" 80S DEG F ACROSS WEST CENTRAL KANSAS.
NOT EXPECTING ANY CONVECTION AS A RESULT OF THE EML ADVECTION ACROSS
SW KANSAS.

FRIDAY:

A WAA PATTERN WILL STRENGTHEN FRIDAY WITH THE EML SPREADING FURTHER
NORTH AND 850 HPA TEMPERATURES WARMING TO 33 DEC C. 700 HPA TEMPERATURES
WILL ALSO BE VERY WARM AND NEAR 16 DEG C. THERE MIGHT BE AN ISOLATED
STORM NEAR HAYS FRIDAY EVENING, BUT AM DUBIOUS OF THIS GFS SOLUTION
SO HAVE KEPT POPS IN SLIGHT CATEGORY GIVEN THE STOUT EML. THERE IS ALSO
NOT MUCH IN THE WAY OF UPPER LEVEL SUPPORT AS 500 HPA HEIGHT INCREASES
ARE EXPECTED ACROSS THE REGION ASSOCIATED WITH MID LEVEL SHORTWAVE RIDGING.
TEMPERATURES WILL BE HOT AND IN THE 90S DEG F. IF THE ECMWF SOLUTION
IS CORRECT, THEN A 100 DEGREE DAY IS POSSIBLE FOR SOME LOCATIONS AND
TEMPERATURES NEED TO BE INCREASED IN THE FUTURE.

SATURDAY AND BEYOND:

FOLLOWED THE ECMWF SOLUTION FOR THIS PERIOD. A VERY BROAD MID LEVEL
TROUGH IS EXPECTED ACROSS THE GREAT BASIN. ANY JET LEVEL DYNAMICS
LOOK TO REMAIN WELL NORTH OF KANSAS WITH GREATEST CHANCE OF HIGHER
IMPACT SEVERE WEATHER NORTH OF THE REGION. THERE COULD BE SOME STORMS
ACROSS SOUTHWEST KANSAS THROUGH THE WEEKEND, HOWEVER, THE ATMOSPHERE
LOOKS PRETTY CAPPED. MADE A FEW TWEAKS TO THE ALLBLEND POPS (CLEANED
UP) AND WARMED TEMPERATURES UP WITH A BIAS TOWARDS THE ECMWF.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1218 PM CDT TUE MAY 22 2012

A TIGHT PRESSURE GRADIENT COMBINED WITH 30-40KT WINDS IN THE
900-850MB LEVEL WILL RESULT SUSTAINED WINDS OF AROUND 25 KNOTS
THROUGH THE REMAINDER OF THE DAY...ESPECIALLY AT DDC AND HYS.
THESE GUSTY WINDS WILL SUBSIDE SOME AFTER SUNSET BUT BASED ON THE
SURFACE PRESSURE GRADIENT SUSTAINED WIND SPEEDS OF 15 TO 20 KNOTS
STILL APPEARS LIKELY. A LOW LEVEL JET IS FORECAST TO DEVELOP
TOWARDS 06Z WITH WIND SPEEDS OF 50 TO 55 KNOTS BETWEEN 1500 AND 2000 FEET
SO INSERTED A WIND SHEAR GROUP INTO THE TAFS OVERNIGHT. BUFR
SOUNDINGS CONTINUE TO INDICATE VFR CONDITIONS OVER THE NEXT 24
HOURS.


&&

.PRELIMINARY POINT TEMPS/POPS...
DDC  65  97  63  86 /   0  10  10  10
GCK  64  98  58  85 /   0  10  10  10
EHA  63  99  58  91 /  20   0  10  10
LBL  65 102  61  89 /  20   0  10  10
HYS  67  93  61  83 /   0  20  20  10
P28  66  93  70  89 /   0   0  10  10

&&

.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...BURGERT
SHORT TERM...BURGERT
LONG TERM...SUGDEN
AVIATION...BURGERT







AREA FORECAST DISCUSSION

NWS DODGE CITY KS

 131 PM CDT TUE MAY 22 2012

...UPDATED SHORT TERM DISCUSSION...

.SYNOPSIS...
ISSUED AT 1218 PM CDT TUE MAY 22 2012

A 500MB UPPER TROUGH WAS LOCATED NEAR THE SOUTHWEST COAST OF BRITISH
COLUMBIA AND NORTHWEST WASHINGTON AT 12Z TUESDAY. A 120-140KT
UPPER LEVEL JET WAS PLACE NEAR AND JUST SOUTHWEST OF THE BASE OF
THIS UPPER TROUGH. 90-110 METER HEIGHT FALLS WERE OBSERVED ACROSS
EASTERN IDAHO AND WESTERN MONTANA. A WESTERLY FLOW EXTENDED
ACROSS THE ROCKIES INTO THE WESTERN HIGH PLAINS WITH +12 TO +13C
700MB TEMPERATURES STRETCHING FROM EASTERN WYOMING/WESTERN
NEBRASKA INTO NORTHEAST NEW MEXICO. UNDER THESE WARM 700MB
TEMPERATURES AT THE SURFACE THERE WAS A TROUGH OF LOW PRESSURE
ACROSS WESTERN NEBRASKA AND EXTREME EASTERN COLORADO/FAR WESTERN
KANSAS.

&&

.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 128 PM CDT TUE MAY 22 2012

RAP, NAM AND HRRR PLACE THE SURFACE TROUGH OF LOW PRESSURE NEAR
THE COLORADO BORDER THIS EVENING. MODEL SOUNDINGS AT 00Z
WEDNESDAYS IN THIS AREA INDICATING LITTLE TO NO CIN WITH A
TEMPERATURES DRY ADIABATIC UP TO AROUND THE 600MB LEVEL WHERE SOME
MOISTURE IS PRESENT. ALSO OBSERVING SOME INSTABILITY PRESENT AS
WELL SO AM UNABLE TO COMPLETELY RULE OUT A EARLY EVENING
THUNDERSTORM DEVELOPING NEAR THE COLORADO BORDER EARLY THIS
EVENING. RAP AND HRRR DO HINT AT A FEW STORMS DEVELOPING AFTER 22Z
NEAR THE ELKHART WHERE THE BETTER INSTABILITY ARE FORECAST TO BE
LOCATED. WITH THIS IN MIND THE PREVIOUS PRECIPITATION FORECAST FOR
EXTREME SOUTHWEST KANSAS STILL APPEARS TO BE ON TRACK. ALSO BASED
ON THE INVERTED V TYPE OF SOUNDINGS IT DOES APPEAR THAT STRONG
WINDS UP TO 60 OR 70 MPH WILL BE THE MAIN HAZARD. ANY STORM THAT
DOES DEVELOP EARLY THIS EVENING IS EXPECTED TO END BEFORE MIDNIGHT
BUT MAY MOVE AS FAR EAST AS LIBERAL IF THESE A COLD POOL CAN BE
DEVELOPED FROM STORMS. AFTER MIDNIGHT SOUTH WINDS OF 15 TO 25 MPH
ARE EXPECTED TO CONTINUE AND BASED ON TEMPERATURES EARLIER THIS
MORNING WILL FAVOR OVERNIGHT LOWS AROUND 5F WARMER THAN GUIDANCE.

ON WEDNESDAY A SURFACE TROUGH/DRYLINE WILL SLIDE EAST INTO
WESTERN KANSAS DURING THE DAY AS A COLD FRONT DROPS SOUTH INTO
NORTHWEST KANSAS BY LATE MORNING. THE COLD FRONT IS EXPECTED TO BE
LOCATED FROM WEST CENTRAL KANSAS AND NORTH CENTRAL KANSAS BY THE
MID AFTERNOON AS WARM MID LEVEL TEMPERATURES SPREADS EAST ACROSS
SOUTHWEST KANSAS. MODEL SOUNDINGS INDICATING ANOTHER DAY OF GOOD
MIXING AND BASED ON MODEL SOUNDINGS AT 00Z THURSDAY IT CURRENTLY
APPEARS HIGHS AROUND 100 DEGREES WILL STILL BE POSSIBLE WEST OF
THE DRYLINE. EAST OF THE DRYLINE AND NEAR THE COLD FRONT THE HIGHS
WILL BE SLIGHTLY COOLER AND RANGE FROM THE LOW TO MID 90S.


.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 330 AM CDT TUE MAY 22 2012

MEDIUM RANGE MODELS SHOW AN UPPER LEVEL TROUGH OF LOW PRESSURE
DROPPING SOUTHEAST ACROSS THE NORTHERN ROCKIES WEDNESDAY THEN
TURNING EASTWARD ACROSS THE WESTERN HIGH PLAINS OF NORTHEASTERN
COLORADO AND WESTERN NEBRASKA WEDNESDAY NIGHT BRINGING WIDESPREAD
PRECIP CHANCES TO THE DAKOTAS SOUTHWARD INTO NEBRASKA AND
POTENTIALLY NORTHERN KANSAS INTO THURSDAY. AN ATTENDANT COLD
FRONT IS PROJECTED TO PUSH SOUTH INTO WESTERN KANSAS SOMETIME EARLY
THURSDAY BEFORE STALLING OUT SOMEWHERE ACROSS SOUTHWEST KANSAS OR
POSSIBLY EVEN NORTHERN OKLAHOMA AS ANOTHER SURFACE LOW DEVELOPS
ACROSS NORTHEASTERN NEW MEXICO AND THE PANHANDLES REGION. HOWEVER,
THE BEST DYNAMIC SUPPORT ALOFT WILL REMAIN JUST TO OUR NORTH ACROSS
NEBRASKA AND POSSIBLY NORTHERN KANSAS WITH A STRONG +100KT UPPER
LEVEL JET EXITING EASTWARD OUT OF THE ROCKIES. SHOWERS AND
THUNDERSTORMS ARE LIKELY TO DEVELOP WEDNESDAY NIGHT INTO THURSDAY
ALONG THE APPROACHING FRONTAL BOUNDARY FROM THE UPPER MIDWEST DOWN
INTO NEBRASKA BUT ARE EXPECTED REMAIN JUST OFF TO OUR NORTH AND
NORTHEAST WHERE THE BEST UPPER LEVEL SUPPORT WILL BE. FOR THE MOST
PART, DRIER CONDITIONS ARE EXPECTED ACROSS SOUTHWEST AND SOUTH
CENTRAL KANSAS THROUGH THE END OF THE WEEK.

TEMPERATURES WILL REMAIN WELL ABOVE NORMAL WEDNESDAY AS A DEEPENING
SURFACE LOW IN EXTREME EASTERN COLORADO CONTINUES TO INFLUENCE A
SOUTH TO SOUTHWESTERLY LOW LEVEL FLOW INTO WESTERN KANSAS. THIS WILL
ENHANCE WARM AIR ADVECTION INTO THE AREA WITH H85 TEMPERATURES IN
THE MID TO UPPER 20S(C) ACROSS CENTRAL KANSAS TO JUST ABOVE 30C IN
SOUTHWEST KANSAS. LOOK FOR WIDESPREAD 90S(F) WEDNESDAY AFTERNOON
WITH NEAR 100F POSSIBLE IN EXTREME SOUTHWEST KANSAS. TEMPERATURES
WILL DROP THURSDAY IN RESPONSE TO A COLD FRONT PUSHING ACROSS
WESTERN KANSAS EARLY IN THE DAY. THIS WILL ALLOW COOLER AIR TO
FILTER SOUTH INTO THE AREA WITH H85 TEMPERATURES IN THE LOW TO MID
20S(C) ACROSS CENTRAL AND SOUTHWEST KANSAS. HOWEVER, HIGHS COULD BE
AN ISSUE CLOSER TO THE OKLAHOMA BORDER WHERE THE FRONTAL BOUNDARY IS
EXPECTED TO STALL OUT. A WARMING TREND IS THEN LIKELY INTO THE
WEEKEND AS UPPER LEVEL TROUGHING SETS UP ACROSS THE INTERMOUNTAIN
WEST.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1218 PM CDT TUE MAY 22 2012

A TIGHT PRESSURE GRADIENT COMBINED WITH 30-40KT WINDS IN THE
900-850MB LEVEL WILL RESULT SUSTAINED WINDS OF AROUND 25 KNOTS
THROUGH THE REMAINDER OF THE DAY...ESPECIALLY AT DDC AND HYS.
THESE GUSTY WINDS WILL SUBSIDE SOME AFTER SUNSET BUT BASED ON THE
SURFACE PRESSURE GRADIENT SUSTAINED WIND SPEEDS OF 15 TO 20 KNOTS
STILL APPEARS LIKELY. A LOW LEVEL JET IS FORECAST TO DEVELOP
TOWARDS 06Z WITH WIND SPEEDS OF 50 TO 55 KNOTS BETWEEN 1500 AND 2000 FEET
SO INSERTED A WIND SHEAR GROUP INTO THE TAFS OVERNIGHT. BUFR
SOUNDINGS CONTINUE TO INDICATE VFR CONDITIONS OVER THE NEXT 24
HOURS.


&&

.PRELIMINARY POINT TEMPS/POPS...
DDC  65  96  62  88 /   0  10  10  10
GCK  64  98  60  85 /  10  10  10  10
EHA  62  99  60  87 /  20  10  10  10
LBL  65 102  62  88 /  10  10  10  10
HYS  65  92  63  84 /   0  10  10  10
P28  66  92  68  92 /   0  10  10  10

&&

.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...BURGERT
SHORT TERM...BURGERT
LONG TERM...JJOHNSON
AVIATION...BURGERT







AREA FORECAST DISCUSSION

NWS GOODLAND KS

 1053 AM MDT TUE MAY 22 2012

.UPDATE...
ISSUED AT 1049 AM MDT TUE MAY 22 2012

TEMPERATURES WARMING RAPIDLY ACROSS THE NW CWA...WITH POINTS
ALREADY NEARING 90 DEGREES BEFORE 17Z. HRRR AND RUC CATCHING ONTO
THIS RAPID WARMING PRETTY WELL AND TRENDED FORECAST IN THIS
DIRECTION...WITH SOME VALUES NEAR 100 POSSIBLE IN THE NW PORTION
OF THE COUNTY. STILL ASSESSING NEED FOR ANY FIRE HIGHLIGHTS AS
LOWEST HUMIDITIES CURRENTLY IN AREA OF LIGHTEST WINDS...AND STILL
SOMEWHAT UNCLEAR HOW FAR EAST DRYLINE WILL MIX.

UPDATE ISSUED AT 813 AM MDT TUE MAY 22 2012

12Z RAOBS INDICATED DEEP LAYER OF NEARLY DRY ADIABATIC LAPSE RATES
HAVE EXPANDED TO THE EAST FROM 24 HOURS AGO...WITH LBF OBSERVING
VERY STEEP LAPSE RATES BETWEEN H8 AND H65...WITH HIGH LAPSE RATES
EXTENDING UP TO H45. MIXING OUT MORNING INVERSION ONLY REQUIRES
TEMPS IN THE MID 80S AND REDUCES CINH TO AROUND 50 J/KG. WITH
TEMPS EXPECTED TO BE WARMER THAN THAT AND DEEPER MOISTURE EXPECTED
TO THE EAST OF DRYLINE...THINK SMALL THREAT FOR THUNDERSTORMS
EXISTS THIS AFTERNOON AND EVENING. NEAR SFC FORCING WILL BE
STRONGEST ALONG DRYLINE...WHERE OVERALL MOISTURE PROFILES WILL BE
MUCH SHALLOWER...WHICH MAY LIMIT CONVECTIVE INITIATIONS AS
AVAILABLE MOISTURE FOR PARCELS IS DILUTED WITH DEEP MIXING. HAVE
MODIFIED FORECAST TO ACCOUNT FOR SOME LATE AFTERNOON STORMS ALONG
DRY LINE...BUT OVERALL COVERAGE WILL BE LOW.

&&

.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 230 AM MDT TUE MAY 22 2012

TODAY...VERY WARM WITH RECORD OR NEAR RECORD HIGH TEMPERATURES
POSSIBLE FOR MANY. FULL 850 MIXING WOULD SUPPORT HIGHS IN THE MID
TO UPPER 90S. HOWEVER...MET/MAV GUIDANCE AND BIAS CORRECTED GRIDS
A FEW DEGREES COOLER. THINKING THAT THE STRONG SOUTH WINDS (NOT
TERRIBLY FAVORABLE FOR STRONG WARMING COMPARED TO A SOUTHWEST OR
WEST DIRECTION) WHICH MAY FLIRT WITH ADVISORY CRITERIA GUSTS IN
THE NORTON AND HILL CITY AREAS AND PLENTIFUL LOW LEVEL MOISTURE
(DEWPOINTS IN THE 50S) MAY PUT A DENT IN THE FULL MIXING AND
PRODUCE HIGHS CLOSER TO THE MET/MAV GUIDANCE. HAVE SPLIT THE TWO
SCENARIOS AND GONE WITH HIGHS IN THE LOW TO MID 90S.

WILL KEEP SILENT POPS GOING ALONG/NEAR THE CO/KS BORDER LATE THIS
AFTERNOON WHERE LOW LEVEL FORCING AND MID LEVEL MOISTURE MAY
CREATE SOME HIGH BASED CU/TCU.

TONIGHT...COLD FRONT MOVES INTO THE NORTHWEST PORTION OF THE AREA
BY SUNRISE. OTHERWISE...DRY WITH MILD OVERNIGHT LOWS IN THE MID
50S TO MID 60S.

WEDNESDAY...STILL NO CLEAR SOLUTION AS TO WHERE THE COLD FRONT
GETS HUNG UP WHICH WILL PLAY A CRUCIAL ROLE IN HIGH TEMPERATURES.
RIGHT NOW IT APPEARS AREAS SOUTH OF THE INTERSTATE WILL CONTINUE
ON THE HOT SIDE WITH HIGHS IN THE LOW TO MID 90S...MAYBE EVEN A
BIT HOTTER. NORTH OF THE FRONT HIGHS GENERALLY IN THE 80S. POST
FRONTAL MOISTURE INCREASES VERY LATE IN THE DAY AS AN UPPER TROUGH
APPROACHES THE AREA. PRECIPITATION CHANCES WILL REMAIN NORTH OF
THE INTERSTATE WITH THE BEST CHANCE ACROSS THE FAR NORTH/NORTHWEST
PORTIONS OF THE AREA.

.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 230 AM MDT TUE MAY 22 2012

WEDNESDAY NIGHT-THURSDAY NIGHT...GOOD MOISTURE/JET ENERGY AND MID
LEVEL FORCING SUPPORT HIGH CHANCE POPS ACROSS THE NORTHERN 1/4 OF
THE AREA...SIMILAR TO PREVIOUS FORECASTS WEDNESDAY NIGHT. SHOULD
HAVE A LULL THURSDAY MORNING BEFORE ANOTHER DISTURBANCE MOVES
THROUGH THURSDAY AFTERNOON BRINGING ANOTHER CHANCE FOR SHOWERS AND
THUNDERSTORMS. SMALL CHANCES FOR PRECIPITATION CONTINUE THURSDAY
NIGHT...AGAIN PRIMARILY ALONG AND NORTH OF THE INTERSTATE. HIGHS
ON THURSDAY AROUND 70 IN THE FAR NORTHWEST...LOW 80S ACROSS THE
FAR EAST-SOUTH.

FRIDAY THROUGH MONDAY...A LONGWAVE TROUGH WILL BE IN PLACE OVER THE
WESTERN CONUS THROUGH THE PERIOD...AND SEVERAL SHORTWAVE TROUGHS
WILL MOVE EASTWARD AND OVER THE REGION DURING THIS TIME. UPPER LEVEL
SUPPORT FROM THESE TROUGHS ALONG WITH LOW LEVEL SUPPORT FROM A
COUPLE OF FRONTS WILL LEAD TO A POSSIBILITY FOR SHOWERS AND
THUNDERSTORMS THROUGH MUCH OF THE PERIOD. A WARM FRONT WILL LIFT
NORTHWARD ON FRIDAY NIGHT/SATURDAY MORNING...AND THE HIGHEST CHANCE
FOR PRECIPITATION WILL BE IN THE NORTHERN PORTION OF THE AREA.
CONDITIONS WILL BE WINDY DURING THE AFTERNOON ON SATURDAY DUE TO A
SURFACE LOW DEEPENING OVER EASTERN COLORADO AND THE ASSOCIATED
STRENGTHENING OF THE PRESSURE GRADIENT. A COLD FRONT IS EXPECTED TO
MOVE INTO THE AREA FROM THE NORTHWEST ON SATURDAY NIGHT AND INTO
SUNDAY MORNING...WITH THE ECMWF MOVING THE FRONT FURTHER EASTWARD
THAN THE GFS. BOTH MODELS KEEP THE FRONT MOSTLY STATIONARY DURING
THE DAYTIME ON SUNDAY...THEN MOVE IT EASTWARD ON MONDAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 230 AM MDT TUE MAY 22 2012

VFR EXPECTED AT BOTH KGLD AND KMCK. SOUTH WINDS WILL INCREASE
QUICKLY THIS MORNING WITH GUSTS UP TO 30 KTS OR SO AT KGLD AND 35
KTS AT KMCK AFTER 18Z. GUSTS WILL COME DOWN A BIT AFTER SUNSET
ALTHOUGH SUSTAINED WINDS OF 15-20 KTS EXPECTED THROUGH EARLY
WEDNESDAY MORNING BEFORE A COLD FRONT MOVES THROUGH KGLD CLOSE TO
12Z...SLIGHTLY LATER AT KMCK.


&&

.CLIMATE...
ISSUED AT 230 AM MDT TUE MAY 22 2012

RECORD HIGH TEMPERATURES FOR TODAY INCLUDE

GOODLAND.....97 (1939)
HILL CITY....96 (2004)
MCCOOK.......97 (1964)
BURLINGTON...95 (1939)
YUMA.........95
TRIBUNE......100
COLBY........98

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&

$$

UPDATE...JRM
SHORT TERM...007
LONG TERM...007/CJS
AVIATION...007
CLIMATE...007







AREA FORECAST DISCUSSION

NWS GRAY ME

 334 PM EDT TUE MAY 22 2012

.SYNOPSIS...
LOW PRESSURE TO OUR SOUTH WILL PASS EAST OF THE AREA OVERNIGHT. A
COLD FRONT WILL MOVE INTO NORTHERN NEW ENGLAND BY TOMORROW MORNING
AND OFFSHORE LATE TOMORROW. WEAK HIGH PRESSURE WILL MOVE INTO THE
AREA THURSDAY AND FRIDAY WITH A CHANCE OF SHOWERS MAINLY INLAND. A
WARM AND DRY SATURDAY IS ON TAP AS HIGH PRESSURE CRESTS OVER NEW
ENGLAND...THEN A COLD FRONT IS EXPECTED TO SAG FROM WEST TO EAST OVER
NEW ENGLAND SUNDAY AND MONDAY. THE FRONT IS EXPECTED TO PUSH
NORTHWARD THROUGH THE AREA ON TUESDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
A LOW PRESSURE SYSTEM WAS CENTERED NEAR CAPE COD THIS AFTERNOON
WITH A WARM FRONT ARCING INTO SOUTHERN NH AND MAINE. MOISTURE
CONTINUED TO FLOW NORTH INTO THE AREA. AT THE SAME TIME A COLD
FRONT WAS MOVING SLOWLY THROUGH SOUTHERN QUEBEC...NEW YORK...AND
PENNSYLVANIA.

AT THE MOMENT MOST OF THE HEAVIER SHOWERS WERE LOCATED OVER THE
HIGHER TERRAIN OF NORTHERN COOS...FRANKLIN...OXFORD...AND
SOMERSET. THE HRRR AND NAM12 INDICATE A BREAK OVER MUCH OF THE
AREA TONIGHT EXCEPT FOR PERHAPS SOUTHERN NH AND SOUTHWEST MAINE
WHERE MOISTURE CONVERGENCE IS BEST. STILL...EXPECT DRIZZLE AND
WIDESPREAD FOG FOR MUCH OF THE REGION. AS THE COLD FRONT MOVES
INTO THE NH MOUNTAINS AND WESTERN MAINE OVERNIGHT...SHOWERS WILL
BECOME MORE WIDESPREAD. THERE IS SOME ELEVATED INSTABILITY BUT
FELT THERE WAS NOT ENOUGH TO INCLUDE THUNDERSTORMS IN THE
FORECAST. OVERNIGHT LOWS WILL BE IN THE MID 50S.

&&

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
LINE OF SHOWERS WILL WORK SLOWLY SOUTHEAST TOMORROW WITH THE COLD
FRONT ALONG WITH ISOLATED THUNDERSTORMS. QPF AMOUNTS WILL
GENERALLY BE LIGHT HOWEVER ANY CONVECTION WILL BOOST RAINFALL
TOTALS. WE WILL SEE CLEARING AND EVENTUALLY PARTLY SUNNY SKIES
WORK IN FROM THE NORTH BY THE AFTERNOON. THIS WILL CONTRIBUTE TO
HIGH TEMPERATURES IN THE 70S.

THE BOUNDARY ESSENTIALLY STALLS AND BY WASHES OUT BY EVENING AS
THE LOW PRESSURE TO OUR EAST PULLS AWAY AND WE LOSE ANY UPPER
LEVEL PUSH. THIS WILL ENSURE MOISTURE HANGS AROUND IN THE LOW
LEVELS. ONCE THE RAIN ENDS FOG WILL DEVELOP AND BECOME DENSE AFTER
DARK. WEDNESDAY NIGHT`S LOWS WILL BE IN THE LOWER 50S NORTH TO
UPPER 50S SOUTH WITH NEGLIGIBLE TEMPERATURE ADVECTION.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...MEDIUM RANGE MODELS ARE IN
FAIR AGREEMENT IN THE GENERAL PATTERN. WEAK SURFACE HIGH PRESSURE
WILL REMAIN OVER THE AREA THURSDAY AND FRIDAY...BUT SHORTWAVES
ALOFT MOVING THROUGH NEW ENGLAND WILL KEEP A CHANCE OF SHOWERS
EACH DAY...MAINLY INLAND. ON SATURDAY THE RIDGE OVER THE
SOUTHEASTERN UNITED STATES SURGES NORTHWARD INTO NEW ENGLAND FOR A
VERY WARM DAY...WITH SOME LOCATIONS IN NEW HAMPSHIRE POSSIBLY
TOUCHING 90 DEGREES. THEN A WEST-EAST-ORIENTED COLD FRONT WILL SAG
SOUTHWARD ACROSS THE AREA SUNDAY THROUGH TUESDAY. POSITION AND
STRENGTH OF THIS BOUNDARY ARE UNCERTAIN AT THIS TIME. CAN`T RULE
OUT A CHANCE OF AFTERNOON THUNDERSTORMS AND SHOWERS EACH DAY.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
SHORT TERM...MOSTLY VFR CONDITIONS AT THE MOMENT WITH A BREAK IN
PRECIPITATION FOR MOST TERMINALS UNTIL THE EVENING. THE EXCEPTION
WILL BE PORTSMOUTH WHICH STAYS IN AN AREA OF CONVERGENCE. DRIZZLE
AND FOG WILL RETURN AROUND 00Z CAUSING CEILINGS AND VISIBILITIES
TO DROP AGAIN TO IFR/LIFR CATEGORIES. A COLD FRONT WILL MOVE IN
FROM THE WEST TONIGHT WITH RAIN CHANCES INCREASING FROM NW TO SE
THROUGH TOMORROW.

LONG TERM...OCCASIONAL MVFR CONDITIONS IN SCATTERED SHOWERS
THURSDAY AND FRIDAY. VFR SATURDAY THEN POSSIBLE MVFR IN
ANY THUNDERSTORMS SUNDAY.

&&

.MARINE...
SHORT TERM...HAVE ISSUED A SCA FOR HIGH SEAS BEGINNING TONIGHT AND
ENDING TOMORROW EVENING AS LOW PRESSURE PASSES TO THE EAST.

LONG TERM...NO SIGNIFICANT FEATURES DURING THE PERIOD.

&&

.FIRE WEATHER...
SCATTERED SHOWERS AND HIGH RELATIVE HUMIDITIES WILL LAST THROUGH
FRIDAY WITH A COLD FRONTAL PASSAGE AND MORE SUBSTANTIAL RAINS
SATURDAY.

&&

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 6 PM THIS EVENING
     TO 8 PM EDT WEDNESDAY FOR ANZ150-152-154.

&&

$$

HANES/ST.JEAN










AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 433 PM EDT TUE MAY 22 2012

.SYNOPSIS...
ISSUED AT 430 PM EDT TUE MAY 22 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
THE GULF OF ALASKA INTO THE NW CONUS AND A FLAT DOWNSTREAM RIDGE
FROM THE SRN PLAINS TO THE UPPER MS VALLEY RESULTING IN WRLY FLOW
THROUGH THE NRN GREAT LAKES. AT THE SFC...A RIDGE EXTENDED FROM
JAMES BAY THROUGH ERN LAKE SUPERIOR AND LAKE MI INTO THE MID MS
VALLEY. SRLY WINDS WERE INCREASING FROM THE PLAINS INTO MN AHEAD OF
LOW PRES OVER THE WRN DAKOTAS. RADAR AND SFC OBS INDICATED AN AREA
OF MAINLY VIRGA/-SHRA/SPRINKLES OVER WRN UPPER MI SUPPORTED BY
305K-310K ISENTROPIC LIFT.
&&

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 430 PM EDT TUE MAY 22 2012

TONIGHT...EXPECT THAT THE -SHRA/SPRINKLES WILL CONTINUE TO DIMINISH
AS THEY MOVE TO THE EAST LATE THIS AFTERNOON AND EVENING. WITH THE
INCREASED CLOUD COVER AND SOUTHERLY WINDS TONIGHT...TEMPS WILL ONLY
DROP OFF INTO THE MID 40S INLAND AND LOWER TO MID 50S FOR DOWNSLOPE
LOCATIONS OVER THE WEST HALF.

WEDNESDAY...AS THE HIGH OVER THE LAKE AND THE PLAINS TROUGH SHIFTS
TO THE EAST...THE GRADIENT WILL INCREASE ACROSS UPPER MICHIGAN.
THE MODELS WERE IN GOOD AGREEMENT IN KEEPING THE MOISTURE/LIFT AHEAD
OF THE MID LEVEL AND SFC TROUGH TO THE WEST...GRADUALLY SHIFTING
INTO WRN LAKE SUPERIOR LATE. WITH THE WAA AND SUNSHINE...TEMPS
SHOULD CLIMB INTO THE MID AND UPPER 70S INLAND WITH COOLER READINGS
NEAR LAKE MICHIGAN. MIXING SHOULD ALSO ALSO A DECENT PORTION OF THE
25-30 KT SRLY 925 MB WINDS TO MIX TO THE SFC. INCREASED WILDFIRE
DANGER IS EXPECTED WITH THE COMBINATION OF 15 TO 20 MPH SFC WINDS
AND GUSTS TO 30 MPH ALONG WITH RH VALUES DROPPING TO AROUND 30
PERCENT.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 430 PM EDT TUE MAY 22 2012

THE PERIOD STARTS 00Z THU WITH A 500MB RIDGE OVER THE E COAST AND
LOWER GREAT LAKES...AND A 500MB TROUGH OVER FROM HUDSON BAY TO SRN
SASK TO THE CENTRAL ROCKIES. THIS PUTS THE CWA UNDER SW FLOW ALOFT.
AT THE SFC...A 994MB LOW WILL BE OVER FAR WRN ONTARIO...WITH A
TROUGH/COLD FRONT EXTENDING SW TO A 986MB LOW OVER ERN CO/WRN KS.
SFC HIGH PRESSURE OVER THE ERN SEABOARD COMBINED WITH LOW PRESSURE
TO OUR W WILL MAKE FOR GUSTY SLY WINDS...WITH 850MB WINDS OF 35-50KTS.
MOST OF THE MOISTURE OVER THE CWA WILL EXIST OVER FAR WRN LAKE
SUPERIOR AT 00Z THU...WITH 1000-500MB RH AROUND 30 PERCENT OVER
CENTRAL UPPER MI. 850MB TEMPS AROUND 18C AT 00Z THU WILL MAKE FOR
WARMER THAN NORMAL TEMPS. CONVECTION SHOULD BE ONGOING OVER WRN LAKE
SUPERIOR AS LOW LEVEL WARM AIR/MOISTURE ADVECTION NOSES INTO THE
VERY MOIST AIRMASS.

BY 12Z THU...THE ONTARIO SFC LOW WILL HAVE MOVED TO JAMES
BAY...WHILE THE CO/KS LOW WILL HAVE BECOME AN ELONGATED LOW FROM KS
TO CENTRAL MN AS AN UPPER SHORTWAVE TROUGH MOVES TO CENTRAL NE.
PRECIP WED NIGHT SHOULD CONTINUE OVER WRN LAKE SUPERIOR AS LOW LEVEL
WARM AIR/MOISTURE ADVECTION CONTINUES TO BE FOCUSED OVER THIS AREA.
WARM AIR ADVECTION DOES LOOK TO SPREAD ACROSS MOST OF THE CWA...BUT
WITH VERY DRY AIR OVER ALL BUT FAR WRN UPPER MI...PRECIP WILL NOT
FOLLOW IT E. THE 12Z/22 GFS CONTINUES TO MOVE THE MOISTURE /AND
THEREFOR THE PRECIP/ A LITTLE FARTHER E /OVERSPREADING MUCH OF WRN
UPPER MI/ WED NIGHT...BUT WILL GO WITH MOST OTHER MODELS IN KEEPING
IT FARTHER W...WHICH MAKES SENSE GIVEN DRY CONDITIONS AND RIDGING IN
PLACE TO THE E. WED NIGHT LOW LOOK QUITE WARM GIVEN 850MB TEMPS
STAYING AROUND 17C AND BREEZY S/SSE SFC WINDS. LOW OVER WRN UPPER
MI...WHERE IT WILL BE CLOUDIER...MAY NOT FALL BELOW 60...WITH LOWS
AOA 50 ELSEWHERE.

FOR THU...THE SHORTWAVE MOVES TO NEAR WRN UPPER MI LATE IN THE
DAY...BRINGING 992MB SFC LOW TO FAR WRN LAKE SUPERIOR/MN ARROWHEAD
BY 00Z FRI. PRECIP WILL REMAIN CONFINED TO FAR WRN UPPER MI/WRN LAKE
SUPERIOR THROUGH 00Z FRI...WITH STRONG SLY LOW LEVEL FLOW CONTINUING
TO BRING DRY AIR TO CENTRAL AND ERN UPPER MI. HIGH TEMPS THU LOOK TO
BE WARMEST OVER THE WRN HALF OF THE U.P. /EXCEPT NEAR IWD DUE TO
INCREASED CLOUD COVER/ IN THE MID TO UPPER 80S. OVER ERN UPPER
MI...HIGHS WILL RANGE FROM THE UPPER 60S NEAR LAKE MI TO AROUND 80
NEAR LAKE SUPERIOR. SFC WIND GUSTS AOA 30MPH LOOK COMMON ON
THU...WHICH WILL TURN ATTENTION TO FIRE WEATHER AS RH FALLS TO
AROUND 30 PERCENT OVER ALL BUT FAR WRN UPPER MI AND NEAR LAKE
SUPERIOR. MUCAPE AROUND 1000J/KG...0-1KM BULK SHEAR AROUND
40KTS...AND 0-6KM BULK SHEAR AOA 50KTS WILL BE SUPPORTIVE OF STRONG
TO SEVERE THUNDERSTORMS OVER WESTERN UPPER MICHIGAN LATE THU
AFTERNOON/EVENING...MAINLY ALONG AND JUST BEHIND THE COLD FRONT.
MAIN SEVERE WX THREATS WOULD BE LARGE HAIL/DAMAGING WINDS.

BY 06Z FRI...MODELS SHOW THE SHORTWAVE/SFC LOW NEAR NRN LAKE
SUPERIOR...WITH THE COLD FRONT OVER CENTRAL OR WRN UPPER MI. THIS
SHOULD BRING WIDESPREAD SHOWERS AND THUNDERSTORMS TO WRN UPPER
MI...BUT COVERAGE WILL DIMINISH AS PRECIP HEADS E INTO THE DRIER AIR
IN PLACE. COLD FRONT SHOULD BE EXITING ERN UPPER MI SHORTLY AFTER
12Z FRI...WITH THE GFS SHOWING QUICKER EASTWARD PROGRESS WITH THE
FRONT THAN MOST OTHER MODELS...SO WILL NOT USE AS FAST A SOLUTION AS
THE GFS.

500MB HIGH BUILDS INTO THE SRN MISSISSIPPI VALLEY BY 12Z SAT AS A
500MB LOW PUSHES INTO THE SW CONUS. A RIDGE FROM THE UPPER HIGH WILL
EXTEND OVER THE DAKOTAS AND MONTANA AT 12Z SAT...BUT WILL MOVE TO
THE WRN CWA BY 18Z SUN AS THE UPPER LOW MOVES TO MT. THIS BRINGS THE
COLD FRONT BACK N AS A WARM FRONT LATE SAT INTO SUN AS A 998MB SFC LOW
MOVES TO SD. PRECIP LOOKS TO MOVE S TO N ACROSS THE CWA SAT NIGHT
THROUGH SUN. MODELS BEGIN TO QUICKLY DIVERGE ON A SOLUTION PAST SUN
AS THE 00Z/22 ECMWF KEEPS THE UPPER LOW OVER MT/SRN SASK THROUGH MON
NIGHT...ANS THE GFS MOVES IT TO JAMES BAY BY 12Z TUE. WILL USE
CONSENSUS OF MODELS FOR SAT THROUGH NEXT TUE...WITH THE FORECAST
BECOMING INCREASINGLY UNCERTAIN SUN NIGHT THROUGH TUE.
&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 725 AM EDT TUE MAY 22 2012

ALTHOUGH THERE WL BE AN INCRS IN MID CLD AT MAINLY IWD/CMX...EXPECT
VFR CONDITIONS TO PREVAIL WITH PLENTY OF LLVL DRY AIR. A TIGHTENING
PRES GRADIENT OVER FAR WRN UPR MI WL CAUSE S WINDS TO TURN GUSTY
WITH DAYTIME HEATING AT IWD TODAY. WITH NOCTURNAL COOLING/A MORE
STABLE THERMAL PROFILE TNGT...EXPECT LLWS AT THAT SITE UNDER THE
SHARPER PRES GRADIENT.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 430 PM EDT TUE MAY 22 2012

SRLY WINDS WILL INCREASE TONIGHT INTO WED AS HIGH PRES SHIFTS TO THE
EAST. EXPECT S WINDS UP TO 25-30 KTS WED INTO THURSDAY NIGHT UNDER
SHARPENING PRES GRADIENT BETWEEN THE DEPARTING HIGH AND A SLOWLY
APPROACHING LO PRES TROF FROM THE W. THE STRONGEST WINDS ARE
EXPECTED OVER CENTRAL LAKE SUP...WHERE TERRAIN INFLUENCE MAY ENHANCE
THE S WIND. THE WIND AT HIGHER PLATFORMS SUCH AS STANNARD ROCKS MAY
ALSO EXCEED 35 KTS...BUT THE HIGH STABILITY OVER THE RELATIVELY COOL
LAKE WATERS WILL PREVENT THESE STRONGER WINDS FROM MIXING TO THE
SURFACE. LOOK FOR LIGHTER WINDS UNDER 20 KTS ON FRI/SAT WITH A
RELATIVELY WEAK PRES GRADIENT ASSOCIATED WITH HIGH BUILDING INTO THE
REGION  FOLLOWING A COLD FRONTAL PASSAGE ON FRI.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...KC
MARINE...JLB








AREA FORECAST DISCUSSION

NWS WILMINGTON NC

 305 PM EDT TUE MAY 22 2012

.SYNOPSIS...
AN UPPER DISTURBANCE WILL BRING SHOWERS AND THUNDERSTORMS TO THE
AREA THROUGH THURSDAY. A WARMING AND DRYING TREND WILL FOLLOW
FRIDAY THROUGH EARLY NEXT WEEK...AS AN UPPER RIDGE INTENSIFIES
OVER THE CAROLINAS.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS OF 1245 PM TUESDAY...RADAR SHOWS SHOWERS DEVELOPING ACROSS THE
LOWER PEE DEE REGION WITH AN INCOMING VORTICITY LOBE...AND ALSO SOME
ACTIVITY ACROSS NORTHERN SECTIONS OF PENDER AND BLADEN COUNTIES.
VISIBLE SATELLITE (AND GLANCES OUT THE WINDOW) SHOW THE CUMULUS
FIELD IN AND AROUND WILMINGTON IS PRIMED FOR ACTIVITY AS WELL. THIS
REQUIRES ONLY SMALL CHANGES TO THE PREVIOUS FORECAST. DISCUSSION
FROM 1030 AM FOLLOWS...

TROPICAL DEPRESSION ALBERTO IS NO MORE. THE CONVECTION HAS BEEN
SHEARED OFF AND AWAY FROM THE LOW-LEVEL CIRCULATION MEANING THERE IS
NO LONGER A METHOD FOR ALBERTO TO EVACUATE AIR AND MAINTAIN LOWER
PRESSURES IN THE CENTER OF THE CIRCULATION. ALBERTO`S REMNANT
CIRCULATION IS CAUGHT UP IN THE SOUTHWEST FLOW AHEAD OF AN INCOMING
NEGATIVELY TILTED UPPER LEVEL TROUGH THAT WILL MOVE FROM THE
ALABAMA/GEORGIA BORDER THIS MORNING INTO SOUTH CAROLINA TONIGHT. THE
NEGATIVE TILT SHOULD BECOME SO EXTREME TONIGHT THE SYSTEM ACTUALLY
WILL CUT OFF INTO A CLOSED UPPER LOW WHICH SHOULD WOBBLE SLOWLY
OVERHEAD WEDNESDAY. FALLING MID-LEVEL TEMPERATURES AND A JUICY
SUBTROPICAL AIRMASS HERE AT THE SURFACE SPELL GROWING VERTICAL
INSTABILITY...WITH CAPE VALUES RISING TO AROUND 1500 J/KG THIS
AFTERNOON.  WITH THE HELP OF MESOSCALE LIFT PROVIDED BY THE
SEABREEZE FRONT...SHOWERS AND THUNDERSTORMS SHOULD DEVELOP EARLY
THIS AFTERNOON JUST INLAND FROM THE COAST. THE ONLY AREAS THAT MIGHT
BE COMPLETELY SPARED ARE THE SOUTH-FACING BEACHES WHERE COOLER
ONSHORE WINDS BEHIND THE SEABREEZE WILL DEVELOP EARLY ENOUGH THIS
AFTERNOON. THE LATEST HRRR SHOWS THIS CLASSIC WEATHER PATTERN WELL
AND IS THE BASIS FOR OUR MORNING FORECAST UPDATE.

BY MID TO LATE AFTERNOON CONTINUED HEATING INLAND AND THE APPROACH
OF THE SURFACE COLD FRONT SHOULD PRODUCE SCATTERED SHOWERS AND
STORMS INLAND AS WELL. SPC HAS CENTRAL SOUTH CAROLINA OUTLOOKED IN A
"SLIGHT RISK" FOR SEVERE WEATHER WITH THE COLDER TEMPERATURES ALOFT
AND BETTER SHEAR PROFILES CLOSER TO THE NEGATIVELY TILTED UPPER
TROUGH. CONVECTIVE ACTIVITY MAY LINGER INTO THE EVENING...WITH
PERHAPS A SECOND ROUND OF SHOWERS AND STORMS OVERNIGHT AS THE CORE
OF THE COLDEST TEMPERATURES ALOFT ROTATE INTO EASTERN SOUTH CAROLINA.

HIGHS TODAY SHOULD REACH THE MID 80S AWAY FROM THE OCEAN. LOWS
TONIGHT SHOULD FALL TO 65-70...WARMEST AT THE BEACHES.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM TUESDAY...BOTH WED AND THU WILL BE IMPACTED BY A
COLD POOL ALOFT PASSING OVER THE FORECAST AREA...ALTHOUGH BY
THURSDAY THIS FEATURE WILL BE EXITING TO THE NORTH AND TEMPS
ALOFT WILL BEGIN WARMING...ESPECIALLY LATE IN THE DAY THURSDAY.

POTENTIALLY SHARP LAPSE RATES WEDNESDAY AFTERNOON INTO EVENING
WARRANTS MENTION OF HAIL AND GUSTY WINDS DESPITE ONLY "SEE TEXT"
WORDING AT THIS TIME FROM SPC. 500MB TEMPS SHOULD DIP TO -15 TO
-16 DEG CELSIUS OVERHEAD NEAR PEAK HEATING.

MENTIONABLE POP VALUES EXTEND INTO THURSDAY BUT WARMING ALOFT
MAY INHIBIT CONVECTION COMPARED TO WED. GREATER COVERAGE AND
TSTM INTENSITY REMAINS FAVORED WED AFTERNOON AS THE CORE OF THE
COOL POOL TRACK OVERHEAD.

MAX TEMPS SIMILAR WED AND THU...MAINLY MIDDLE AND UPPER 80S ACROSS
MOST INLAND LOCATIONS...AND LOWER 80S ALONG THE IMMEDIATE COAST.
PRIMARILY MIDDLE 60S FOR LOWS EACH MORNING GIVEN ONSHORE FLOW
AND PROJECTED DEWPOINTS.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 3 PM TUESDAY...FEW CHANGES TO THE LONG TERM FORECAST THIS
AFTERNOON WITH CONVECTION TAKING PRECEDENCE. MAIN THEME REMAINS
HOT HOWEVER AS MEDIUM RANGE GUIDANCE CONTINUES TO BUILD THE 500MB
RIDGE ACROSS THE SOUTHEAST FOR THE WEEKEND CONTINUING INTO MONDAY.
THE PATTERN DOES SHOW INDICATIONS OF BREAKING DOWN TUESDAY AS
CLOSED LOW IN THE WEST GETS KICKED OUT AND LOWERS HEIGHTS FROM
NORTH TO SOUTH.

&&

.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
AS OF 19Z...SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP
THIS AFTERNOON AHEAD OF AN APPROACHING COLD FRONT AND UPPER
IMPULSE. CONFIDENCE IN TIMING OF ACTIVITY INTO ANY TERMINAL IS
ONLY LOW TO MODERATE. ONE IMPULSE MOVING THROUGH THE FLO TERMINALS
ATTM SHOULD ENHANCE SEA BREEZE ACTIVITY FOR SEVERAL HOURS THIS
AFTERNOON FROM MYR TO ILM. WILL INDICATE SHOWERS/WITH TEMPO MVFR
AT ALL TERMINALS THIS AFTERNOON...WITH SHORT-TERM AMENDMENTS AS
RADAR COVERAGE INDICATES. VCTS WILL BE MOST LIKELY AT THE COASTAL
TERMINALS. SHORT PERIODS OF IFR ARE LIKELY WITH ANY THUNDERSTORMS
BUT THE DURATION SHOULD BE TOO SHORT TO MENTION IN AT LEAST THE
18Z TAFS. THIS CONVECTION SHOULD END BY LATE AFTERNOON...WITH A
SECOND ROUND OF CONVECTION DEVELOPING THIS EVENING PERSISTING
UNTIL MIDNIGHT OR EVEN AFTER AS THE UPPER IMPULSE ROTATES THROUGH.

THUNDERSTORM DEBRIS CLOUDINESS SHOULD SLOWLY THIS OUT AFTER THE
PRECIPITATION ENDS AFTER MIDNIGHT...LEAVING THE WINDOW OPEN FOR BR
DEVELOPMENT. ATTM WILL INDICATE ONLY MVFR CONDITIONS AT FLO/LBT DUE
TO LIGHTER SURFACE WINDS AND LESS POTENTIAL CLOUD COVER. PATCHY
DENSE FOG COULD OCCUR ESPECIALLY IN SHELTERED AREAS WHERE SKIES
CLEAR OUT. ANY REDUCED FLIGHT CONDITIONS SHOULD IMPROVE RAPIDLY
AROUND SUNRISE WITH SHOWERS AND THUNDERSTORMS AGAIN POSSIBLE BY MID
MORNING.

EXTENDED OUTLOOK...SCATTERED SHOWERS/MVFR...WITH ISOLATED
THUNDERSTORMS/TEMPO IFR POSSIBLE THROUGH THE EXTENDED PERIOD.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1245 PM TUESDAY...CURRENT OBSERVATIONS MATCH THE PREVIOUS
FORECAST CLOSELY...NO CHANGES ARE REQUIRED. PREVIOUS DISCUSSION FROM
1030 AM FOLLOWS...

ALBERTO IS A DISSIPATING POST-TROPICAL DEPRESSION LOCATED ABOUT 250
MILES EAST-SOUTHEAST OF CAPE FEAR. WINDS ARE CURRENTLY SOUTH TO
SOUTHWEST ACROSS OUR COASTAL WATERS INDICATING THERE HAS BEEN NO
INFLUENCE FROM ALBERTO`S SMALL CIRCULATION. OUR WINDS ARE ACTUALLY
INFLUENCED BY THE CYCLONIC FLOW AROUND AN AREA OF LOW PRESSURE AND
COLD FRONT CURRENTLY ACROSS THE INLAND CAROLINAS. THIS SYSTEM IS NOT
EXPECTED TO REACH THE COAST... INSTEAD STALLING TONIGHT AND
DISSIPATING ON WEDNESDAY. UNTIL THEN... SOUTHWEST 10-15 KNOT WINDS
ARE EXPECTED...STRONGEST ALONG THE COAST THIS AFTERNOON AND FARTHER
AWAY FROM THE COAST TONIGHT. THUNDERSTORMS ARE EXPECTED TO DEVELOP
ALONG THE SEABREEZE FRONT THIS AFTERNOON. SOME OF THESE COULD BE ON
OR VERY NEAR THE BEACHES...SO MARINERS WILL WANT TO PAY CLOSE
ATTENTION TO THE SKY EARLY THIS AFTERNOON. THERE SHOULD BE A LULL IN
SHOWER/T-STORM ACTIVITY LATER THIS AFTERNOON INTO EARLY
EVENING...BUT NEW SHOWERS AND STORMS MAY DEVELOP OFFSHORE LATE THIS
EVENING AND OVERNIGHT.

SEAS CONTINUE TO BE THE ONE AREA WE ARE RECEIVING AN INFLUENCE FROM
FORMER TROPICAL STORM ALBERTO. 3-4 FT SEAS WILL CONTINUE INTO
TONIGHT AS ALBERTO`S SWELL IS ADDED TO LOCALLY GENERATED WIND WAVES.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...THE BIGGEST THREAT WED AND THU WILL BE
ISOLATED TO SCATTERED TSTMS THAT COULD TRACK ACROSS THE WATERS
INTACT. THIS WILL INTRODUCE CLOUD TO WATER LIGHTNING STRIKES AND
LOCALLY ROUGH CONDITIONS. OUTSIDE OF TSTMS...MAINLY SOUTHERLY
WINDS 15 KNOTS OR LESS WED AND THU...WITH A FEW HIGHER AFTERNOON
GUSTS ENHANCED BY THE SEA BREEZE CIRCULATION. 3-4 FOOT SEAS WED
AND THU COMPRISED OF SE WAVES 2-3 FEET IN 8-10 SECOND INTERVALS
AND S WAVES AROUND 2 FEET IN 5-6 SECOND WAVE INTERVALS.

LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3 PM TUESDAY...NORTHEAST WINDS FOR THE FIRST COUPLE OF DAYS
VEERING TO THE EAST FOR LATE IN THE WEEKEND AS HIGH PRESSURE
RESIDES TO THE WEST AND LOW PRESSURE TO THE EAST. LOWER CONFIDENCE
IN SPEEDS AS THE LOWS TO THE EAST ARE WILD CARDS. OVERALL EXPECT
SPEEDS TO REMAIN BELOW FLAG CRITERIA HOWEVER. EXPECT SUMMER LIKE
SEAS OF 2-4 FEET.


&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...TRA
SHORT TERM...MJC
LONG TERM...SHK
AVIATION...MRR/TRA





AREA FORECAST DISCUSSION

NWS WILMINGTON NC

 1242 PM EDT TUE MAY 22 2012

.SYNOPSIS...
A SOUTHWESTERLY FLOW OF LOW LEVEL MOISTURE WILL REMAIN IN PLACE OVER
THE NEXT FEW DAYS WHILE AN UPPER LEVEL DISTURBANCE TRIGGERS
THUNDERSTORMS THIS AFTERNOON THROUGH THURSDAY. AS THIS SYSTEM
EXITS...A WARMUP IS EXPECTED LATE IN THE WEEK AND THROUGH THE
HOLIDAY WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1245 PM TUESDAY...RADAR SHOWS SHOWERS DEVELOPING ACROSS THE
LOWER PEE DEE REGION WITH AN INCOMING VORTICITY LOBE...AND ALSO SOME
ACTIVITY ACROSS NORTHERN SECTIONS OF PENDER AND BLADEN COUNTIES.
VISIBLE SATELLITE (AND GLANCES OUT THE WINDOW) SHOW THE CUMULUS
FIELD IN AND AROUND WILMINGTON IS PRIMED FOR ACTIVITY AS WELL. THIS
REQUIRES ONLY SMALL CHANGES TO THE PREVIOUS FORECAST. DISCUSSION
FROM 1030 AM FOLLOWS...

TROPICAL DEPRESSION ALBERTO IS NO MORE. THE CONVECTION HAS BEEN
SHEARED OFF AND AWAY FROM THE LOW-LEVEL CIRCULATION MEANING THERE IS
NO LONGER A METHOD FOR ALBERTO TO EVACUATE AIR AND MAINTAIN LOWER
PRESSURES IN THE CENTER OF THE CIRCULATION. ALBERTO`S REMNANT
CIRCULATION IS CAUGHT UP IN THE SOUTHWEST FLOW AHEAD OF AN INCOMING
NEGATIVELY TILTED UPPER LEVEL TROUGH THAT WILL MOVE FROM THE
ALABAMA/GEORGIA BORDER THIS MORNING INTO SOUTH CAROLINA TONIGHT. THE
NEGATIVE TILT SHOULD BECOME SO EXTREME TONIGHT THE SYSTEM ACTUALLY
WILL CUT OFF INTO A CLOSED UPPER LOW WHICH SHOULD WOBBLE SLOWLY
OVERHEAD WEDNESDAY. FALLING MID-LEVEL TEMPERATURES AND A JUICY
SUBTROPICAL AIRMASS HERE AT THE SURFACE SPELL GROWING VERTICAL
INSTABILITY...WITH CAPE VALUES RISING TO AROUND 1500 J/KG THIS
AFTERNOON.  WITH THE HELP OF MESOSCALE LIFT PROVIDED BY THE
SEABREEZE FRONT...SHOWERS AND THUNDERSTORMS SHOULD DEVELOP EARLY
THIS AFTERNOON JUST INLAND FROM THE COAST. THE ONLY AREAS THAT MIGHT
BE COMPLETELY SPARED ARE THE SOUTH-FACING BEACHES WHERE COOLER
ONSHORE WINDS BEHIND THE SEABREEZE WILL DEVELOP EARLY ENOUGH THIS
AFTERNOON. THE LATEST HRRR SHOWS THIS CLASSIC WEATHER PATTERN WELL
AND IS THE BASIS FOR OUR MORNING FORECAST UPDATE.

BY MID TO LATE AFTERNOON CONTINUED HEATING INLAND AND THE APPROACH
OF THE SURFACE COLD FRONT SHOULD PRODUCE SCATTERED SHOWERS AND
STORMS INLAND AS WELL. SPC HAS CENTRAL SOUTH CAROLINA OUTLOOKED IN A
"SLIGHT RISK" FOR SEVERE WEATHER WITH THE COLDER TEMPERATURES ALOFT
AND BETTER SHEAR PROFILES CLOSER TO THE NEGATIVELY TILTED UPPER
TROUGH. CONVECTIVE ACTIVITY MAY LINGER INTO THE EVENING...WITH
PERHAPS A SECOND ROUND OF SHOWERS AND STORMS OVERNIGHT AS THE CORE
OF THE COLDEST TEMPERATURES ALOFT ROTATE INTO EASTERN SOUTH CAROLINA.

HIGHS TODAY SHOULD REACH THE MID 80S AWAY FROM THE OCEAN. LOWS
TONIGHT SHOULD FALL TO 65-70...WARMEST AT THE BEACHES.

&&

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 AM TUESDAY...COOL POCKET ALOFT ASSOCIATED WITH MID LEVEL
TROUGH MOVES ACROSS WEDNESDAY MORNING. THEREAFTER COMES WEAK HEIGHT
RISES AND WAA BUT A TRAILING VORT MAX SHOULD STILL MANAGE TO TOUCH
OFF SCATTERED AFTERNOON THUNDERSTORMS. FORECAST INSTABILITY AMPLE
ENOUGH TO DRAW ANOTHER SEE TEXT/5% FOR SEVERE FROM SPC...NOTING LACK
OF SHEAR TO SUPPORT ANY LEVEL OF ORGANIZATION IN CONVECTION.
TEMPERATURES WILL BE VERY CLOSE TO CLIMO. FORCING WILL BE ON THE
WANE FOR THE REMAINDER OF THE PERIOD WITH THE EXIT OF THE UPPER
TROUGH. YET ANOTHER VORT COMES THROUGH ON THE HEELS OF THE EXITING
TROUGH THURSDAY AFTERNOON. ITS A MUCH WEAKER FEATURE SO ONLY LOW
END CHANCE POPS APPEAR WARRANTED FOR WHAT SHOULD END UP BEING WIDELY
SCATTERED OR ISOLATED CONVECTIVE COVERAGE. THURSDAY HIGHS AND LOWS
WILL BE VERY CLOSE TO WEDNESDAYS AND THUS CLIMATOLOGY.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 3 AM TUESDAY...UPPER WAVE FROM THE SHORT TERM GOES ON TO
INTERACT WITH AMPLE MOISTURE STREAMING OUT OF THE CARIBBEAN AND
GUIDANCE SUGGESTS LOW PRESSURE GETS INDUCED IN THE BAHAMAS LATER IN
THE PERIOD. WRF SOLUTION APPEARS RATHER CLIMATOLOGICALLY EXTREME AT
THIS POINT BUT GIVEN THAT SSTS WERE WARM ENOUGH TO ALREADY SUPPORT
ALBERTO TOUGH TO RULE OUT. FOR NOW THE SHALLOWER SYSTEM DEPICTED BY
THE GFS SEEMS MORE APPEALING AND THERE WILL BE NO IMPACT LOCALLY ON
FRIDAY AS UPPER RIDGE BUILDS OVER GULF STATES. JUST ISOLATED
CONVECTION AS NORTHERLY FLOW LOCALLY WILL CONTAIN SOME WEAK SHORT
WAVE IMPULSES AND A HEALTHY SEA BREEZE CIRCULATION WILL DEVELOP. NOT
MUCH CHANGES INTO THE HOLIDAY WEEKEND AND WITH THE AFOREMENTIONED
POSSIBLE LOW OUT OF THE PICTURE THE UPPER RIDGE WILL BE THE DOMINANT
PLAYER. TEMPERATURES WILL RISE ABOVE CLIMATOLOGY. SURFACE FLOW WILL
BE A BIT MORE EASTERLY THAN MOST LATE SPRING WARM UPS TEMPERING THE
WARMTH SLIGHTLY AND PUSHING THE SEA BREEZE WELL INLAND. ISOLATED
CONVECTION EACH AFTERNOON MAY BE SHUNTED ALL THE WAY TO WESTERN
ZONES.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 18Z...SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP THIS
AFTERNOON AHEAD OF AN APPROACHING COLD FRONT AND UPPER IMPULSE.
CONFIDENCE IN TIMING OF ACTIVITY INTO ANY TERMINAL IS ONLY LOW TO
MODERATE. ONE IMPULSE MOVING THROUGH THE FLO TERMINALS ATTM SHOULD
ENHANCE SEA BREEZE ACTIVITY FOR SEVERAL HOURS THIS AFTERNOON FROM
MYR TO ILM. WILL INDICATE SHOWERS/WITH TEMPO MVFR AT ALL TERMINALS
THIS AFTERNOON...WITH SHORT-TERM AMENDMENTS AS RADAR COVERAGE
INDICATES. VCTS WILL BE MOST LIKELY AT THE COASTAL TERMINALS. SHORT
PERIODS OF IFR ARE LIKELY WITH ANY THUNDERSTORMS BUT THE DURATION
SHOULD BE TOO SHORT TO MENTION IN AT LEAST THE 18Z TAFS. THIS
CONVECTION SHOULD END BY LATE AFTERNOON...WITH A SECOND ROUND OF
CONVECTION DEVELOPING THIS EVENING PERSISTING UNTIL MIDNIGHT OR
EVEN AFTER AS THE UPPER IMPULSE ROTATES THROUGH.

THUNDERSTORM DEBRIS CLOUDINESS SHOULD SLOWLY THIS OUT AFTER THE
PRECIPITATION ENDS AFTER MIDNIGHT...LEAVING THE WINDOW OPEN FOR BR
DEVELOPMENT. ATTM WILL INDICATE ONLY MVFR CONDITIONS AT FLO/LBT DUE
TO LIGHTER SURFACE WINDS AND LESS POTENTIAL CLOUD COVER. PATCHY
DENSE FOG COULD OCCUR ESPECIALLY IN SHELTERED AREAS WHERE SKIES
CLEAR OUT. ANY REDUCED FLIGHT CONDITIONS SHOULD IMPROVE RAPIDLY
AROUND SUNRISE WITH SHOWERS AND THUNDERSTORMS AGAIN POSSIBLE BY MID
MORNING.

EXTENDED OUTLOOK...SCATTERED SHOWERS/MVFR...WITH ISOLATED
THUNDERSTORMS/TEMPO IFR POSSIBLE THROUGH THE EXTENDED PERIOD.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1245 PM TUESDAY...CURRENT OBSERVATIONS MATCH THE PREVIOUS
FORECAST CLOSELY...NO CHANGES ARE REQUIRED. PREVIOUS DISCUSSION FROM
1030 AM FOLLOWS...

ALBERTO IS A DISSIPATING POST-TROPICAL DEPRESSION LOCATED ABOUT 250
MILES EAST-SOUTHEAST OF CAPE FEAR. WINDS ARE CURRENTLY SOUTH TO
SOUTHWEST ACROSS OUR COASTAL WATERS INDICATING THERE HAS BEEN NO
INFLUENCE FROM ALBERTO`S SMALL CIRCULATION. OUR WINDS ARE ACTUALLY
INFLUENCED BY THE CYCLONIC FLOW AROUND AN AREA OF LOW PRESSURE AND
COLD FRONT CURRENTLY ACROSS THE INLAND CAROLINAS. THIS SYSTEM IS NOT
EXPECTED TO REACH THE COAST... INSTEAD STALLING TONIGHT AND
DISSIPATING ON WEDNESDAY. UNTIL THEN... SOUTHWEST 10-15 KNOT WINDS
ARE EXPECTED...STRONGEST ALONG THE COAST THIS AFTERNOON AND FARTHER
AWAY FROM THE COAST TONIGHT. THUNDERSTORMS ARE EXPECTED TO DEVELOP
ALONG THE SEABREEZE FRONT THIS AFTERNOON. SOME OF THESE COULD BE ON
OR VERY NEAR THE BEACHES...SO MARINERS WILL WANT TO PAY CLOSE
ATTENTION TO THE SKY EARLY THIS AFTERNOON. THERE SHOULD BE A LULL IN
SHOWER/T-STORM ACTIVITY LATER THIS AFTERNOON INTO EARLY
EVENING...BUT NEW SHOWERS AND STORMS MAY DEVELOP OFFSHORE LATE THIS
EVENING AND OVERNIGHT.

SEAS CONTINUE TO BE THE ONE AREA WE ARE RECEIVING AN INFLUENCE FROM
FORMER TROPICAL STORM ALBERTO. 3-4 FT SEAS WILL CONTINUE INTO
TONIGHT AS ALBERTO`S SWELL IS ADDED TO LOCALLY GENERATED WIND WAVES.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...BROAD AND WEAK HIGH PRESSURE ACROSS THE WESTERN
ATLANTIC IN TANDEM WITH PIEDMONT TROUGHINESS TO BRING SSW FLOW ON
WEDNESDAY. A DOMINANT 3 TO 4 FT SEA STATE WILL BE A COMBO OF SW WIND
CHOP AND E SWELL...BOTH COMPONENTS BEING COMPARABLE IN RELATIVE
STRENGTH. CONDITIONS WILL NOT CHANCE TOO MUCH INTO THURSDAY BUT
THEIR IS SOME UNCERTAINTY. LOW PRESSURE WILL MOVE OUT OF THE
CARIBBEAN AND INTO THE BAHAMAS LATE IN THE PERIOD. THERE IS QUITE A
DIFFERENCE IN GUIDANCE WITH RESPECT TO THIS SYSTEMS EVENTUAL FATE.
FOR THIS PERIOD ITS PRESENCE MAY CUT DOWN ON THE SWELL ENERGY BY
INTERRUPTING THE LONG EASTERLY FETCH.

LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3 AM TUESDAY...FOR THE MOST PART A LARGE AREA OF HIGH PRESSURE
ACROSS THE WESTERN ATLANTIC WILL BE RESPONSIBLE FOR THE LOCAL SET OF
WIND AND WAVES. THERE IS A COMPLICATING FACTOR THAT FRIDAY MAY SEE
SOME KIND OF WEAK LOW OF TROPICAL ORIGINS MOVING PARALLEL TO THE
COAST...AND LIKELY WELL OFFSHORE. THERE ARE SOME MODEL SOLUTIONS
THAT HAVE IT CLOSER AND STRONGER AND THEREFORE MUCH OF A FACTOR IN
THE FORECAST. FOR NOW FOLLOWING WEAKER SOLUTIONS THAT SHOW A WEAK
LOW OR OPEN TROUGH IN THE OTHERWISE EASTERLY FLOW BORNE OF
AFOREMENTIONED HIGH. SEAS IN THE 2 TO 4 FT RANGE AS ALTHOUGH WINDS
WILL REMAIN LIGHT THE EASTERLY FETCH LENGTH COULD BE QUITE LONG AND
ALLOW FOR A SIGNIFICANT SWELL COMPONENT.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

&&

$$

NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...MRR









AREA FORECAST DISCUSSION...CORRECTED

NWS NORMAN OK

 314 PM CDT TUE MAY 22 2012

.DISCUSSION...
CONVECTION IS DEVELOPING AGAIN OVER THE HIGH PLAINS OF NEW MEXICO
AND IS CURRENTLY MOVING INTO CIMARRON COUNTY OKLAHOMA. SOME RECENT
RUNS OF THE LOCAL WRF AND THE HRRR HAVE SUGGESTED ENOUGH
POSSIBILITY OF CONVECTION INCREASING AND PERSISTING EAST AND
SOUTHEAST INTO WESTERN SECTIONS OF THE CWA THAT HAVE ADDED AN AREA
OF ISOLATED STORMS IN THE FIRST PERIOD OUT WEST ALTHOUGH AM
LEAVING THE POPS BELOW 20 PERCENT. THE EVENING SHIFT CAN CONTINUE
TO MONITOR THE TRENDS AND MAKE UPDATES IF NECESSARY. OTHERWISE...
HOT AND GENERALLY DRY WEATHER IS EXPECTED FOR A COUPLE OF DAYS AND
A WINDY DAY IS EXPECTED TOMORROW. A WIND ADVISORY MAY BE NECESSARY
FOR TOMORROW. SOMEWHAT COOLER TEMPERATURES ARE EXPECTED TOWARD THE
WEEKEND ALTHOUGH STILL WARM BY MID-LATE MAY STANDARDS. MEDIUM
RANGE MODELS ARE ALL SHOWING PRECIP DEVELOPING ON MONDAY ACROSS
THE NORTH AND WEST AHEAD OF A COLD FRONT... SO HAVE INTRODUCED
SOME POPS FOR MEMORIAL DAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK  65  91  68  91 /   0   0  10  10
HOBART OK         65  96  66  93 /  10  10  10  10
WICHITA FALLS TX  66  96  69  96 /  10  10  10  10
GAGE OK           64  94  62  90 /  10  10  10  10
PONCA CITY OK     67  90  69  88 /   0   0  10  10
DURANT OK         66  91  67  86 /   0   0  10   0

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&

$$

CORRECTED PRELIMINARY TEMPS/POPS




AREA FORECAST DISCUSSION

NWS NORMAN OK

 1218 PM CDT TUE MAY 22 2012

.AVIATION...
ISOLATED CONVECTION PERSISTS THIS AFTERNOON... BUT IS EXPECTED TO
REMAIN SOUTH AND SOUTHEAST OF THE TAF SITES... SO NO SIGNIFICANT
AVIATION WEATHER CONCERNS ARE EXPECTED TODAY. SOUTH WINDS WILL
INCREASE WEDNESDAY MORNING WITH GUSTS NEAR OR ABOVE 30 KNOTS AT
MANY OF THE TAF LOCATIONS BY 18Z TOMORROW.

&&

.PREV DISCUSSION... /ISSUED 1109 AM CDT TUE MAY 22 2012/

UPDATE...
WILL GO AHEAD AND ADD ISOLATED SHWR/TSTM WORDING ACROSS PORTIONS
OF SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS THIS AFTN. THIS
ACTIVITY IS ASSOCIATED WITH MCV AND SOME DIFFERENTIAL HEATING
BOUNDARIES THAT HAVE DEVELOPED FROM LAST EVENINGS CONVECTIONS
ACROSS WEST TEXAS. OTHERWISE... FORECAST IS IN GOOD SHAPE WITH
WARM AND BREEZY CONDITIONS EXPECTED THIS AFTN.

PREV DISCUSSION... /ISSUED 730 AM CDT TUE MAY 22 2012/

AVIATION...
AN ISOLATED SHOWER OR TWO WILL BE POSSIBLE THROUGH
MID MORNING...OTHERWISE CLOUDS WILL SLOWLY DISSIPATE
DURING THE MORNING.  SOUTH TO SOUTHEAST WINDS WILL
INCREASE BY MID TO LATE MORNING.

PREV DISCUSSION... /ISSUED 418 AM CDT TUE MAY 22 2012/

DISCUSSION...
MID-LEVEL NORTHWEST TO WEST FLOW WILL GRADUALLY TRANSITION
TO A SOUTHWEST FLOW OVER THE NEXT 48 HOURS AS A BROAD
TROUGH TAKES SHAPE OVER THE WESTERN HALF OF THE CONUS.
MEANWHILE...CONVECTION ACROSS TEXAS PANHANDLE HAS WEAKENED
OVERNIGHT WITH MCV-LIKE FEATURE IN WEAK ECHO RETURNS.
TO THE EAST...ISOLATED SHOWERS HAVE BEEN FORMING ACROSS
THE WESTERN THIRD OF OKLAHOMA FROM HARPER COUNTY TO
KIOWA. NAM12 AND RECENT HRRR RUNS ARE MORE BULLISH
WITH THE DEVELOPMENT OF MORE SHOWERS/STORMS BETWEEN
10-15Z ACROSS WESTERN HALF OF FA. WITH RECENT
DEVELOPMENT WILL ADD 20-30 POPS ACROSS WESTERN 1/3 OF
FA. PRECIP THAT DOES DEVELOP SHOULD GRADUALLY WEAKEN
DURING THE MID TO LATE MORNING.

AFTERNOON CONVECTION MAY DEVELOP WEST OF THE AREA BUT
OVERALL COVERAGE MAY LIMIT CHANCES OF IMPACTING WESTERN
OKLAHOMA..SO WILL KEEP POPS RATHER LOW.

SOUTH WINDS WILL INCREASE SOME TODAY AND WILL BECOME RATHER
GUSTY ON WEDNESDAY AS LOW PRESSURE DEEPENS OVER THE
HIGHER TERRAIN.

A SHORTWAVE WILL MOVE FROM THE CENTRAL ROCKIES INTO THE
UPPER MIDWEST LATE WEDNESDAY INTO THURSDAY. THIS FEATURE
WILL HELP PUSH A WEAK SURFACE BOUNDARY INTO NORTHWEST
AND WEST CENTRAL OKLAHOMA WEDNESDAY NIGHT/EARLY THURSDAY.
RATHER WARM 8H TEMPS AND BETTER FORCING NORTH...SHOULD LIMIT
STORM CHANCES WITH THIS BOUNDARY.

AN UPPER RIDGE WILL BUILD OVER THE SOUTHEAST GOING INTO THE
HOLIDAY WEEKEND...WHILE ANOTHER STORM SYSTEM MOVES ACROSS
THE WESTERN THIRD OF THE US.  EC MODEL STRONGER WITH WESTERN
SYSTEM AND MAY BRING A CHANCE OF STORMS TO WESTERN OKLAHOMA
BY SUNDAY...AS IT LIFTS NORTH INTO THE NORTHERN ROCKIES AND
PLAINS. OVERALL...THE HOLIDAY WEEKEND APPEARS MAINLY DRY AND VERY
WARM/HOT WITH BETTER CHANCES FOR STORMS ACROSS WESTERN OK. MODELS
SIGNAL A RETURN TO A NORTHWEST FLOW BY THE MIDDLE OF NEXT WEEK
WHICH MAY BRING BETTER CHANCES FOR STORMS DURING THE LAST DAYS OF
MAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK  65  90  67  90 /  10  10  10  10
HOBART OK         64  95  68  93 /  10  10  10  10
WICHITA FALLS TX  66  97  68  95 /  10  10  10  10
GAGE OK           62  93  62  92 /  10  10  10  10
PONCA CITY OK     65  90  68  91 /  10  10  10  10
DURANT OK         65  93  65  87 /  10   0  10   0

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&

$$




AREA FORECAST DISCUSSION

NWS NORMAN OK

 1109 AM CDT TUE MAY 22 2012

.UPDATE...
WILL GO AHEAD AND ADD ISOLATED SHWR/TSTM WORDING ACROSS PORTIONS
OF SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS THIS AFTN. THIS
ACTIVITY IS ASSOCIATED WITH MCV AND SOME DIFFERENTIAL HEATING
BOUNDARIES THAT HAVE DEVELOPED FROM LAST EVENINGS CONVECTIONS
ACROSS WEST TEXAS. OTHERWISE... FORECAST IS IN GOOD SHAPE WITH
WARM AND BREEZY CONDITIONS EXPECTED THIS AFTN.

&&

.PREV DISCUSSION... /ISSUED 730 AM CDT TUE MAY 22 2012/

AVIATION...
AN ISOLATED SHOWER OR TWO WILL BE POSSIBLE THROUGH
MID MORNING...OTHERWISE CLOUDS WILL SLOWLY DISSIPATE
DURING THE MORNING.  SOUTH TO SOUTHEAST WINDS WILL
INCREASE BY MID TO LATE MORNING.

PREV DISCUSSION... /ISSUED 418 AM CDT TUE MAY 22 2012/

DISCUSSION...
MID-LEVEL NORTHWEST TO WEST FLOW WILL GRADUALLY TRANSITION
TO A SOUTHWEST FLOW OVER THE NEXT 48 HOURS AS A BROAD
TROUGH TAKES SHAPE OVER THE WESTERN HALF OF THE CONUS.
MEANWHILE...CONVECTION ACROSS TEXAS PANHANDLE HAS WEAKENED
OVERNIGHT WITH MCV-LIKE FEATURE IN WEAK ECHO RETURNS.
TO THE EAST...ISOLATED SHOWERS HAVE BEEN FORMING ACROSS
THE WESTERN THIRD OF OKLAHOMA FROM HARPER COUNTY TO
KIOWA. NAM12 AND RECENT HRRR RUNS ARE MORE BULLISH
WITH THE DEVELOPMENT OF MORE SHOWERS/STORMS BETWEEN
10-15Z ACROSS WESTERN HALF OF FA. WITH RECENT
DEVELOPMENT WILL ADD 20-30 POPS ACROSS WESTERN 1/3 OF
FA. PRECIP THAT DOES DEVELOP SHOULD GRADUALLY WEAKEN
DURING THE MID TO LATE MORNING.

AFTERNOON CONVECTION MAY DEVELOP WEST OF THE AREA BUT
OVERALL COVERAGE MAY LIMIT CHANCES OF IMPACTING WESTERN
OKLAHOMA..SO WILL KEEP POPS RATHER LOW.

SOUTH WINDS WILL INCREASE SOME TODAY AND WILL BECOME RATHER
GUSTY ON WEDNESDAY AS LOW PRESSURE DEEPENS OVER THE
HIGHER TERRAIN.

A SHORTWAVE WILL MOVE FROM THE CENTRAL ROCKIES INTO THE
UPPER MIDWEST LATE WEDNESDAY INTO THURSDAY. THIS FEATURE
WILL HELP PUSH A WEAK SURFACE BOUNDARY INTO NORTHWEST
AND WEST CENTRAL OKLAHOMA WEDNESDAY NIGHT/EARLY THURSDAY.
RATHER WARM 8H TEMPS AND BETTER FORCING NORTH...SHOULD LIMIT
STORM CHANCES WITH THIS BOUNDARY.

AN UPPER RIDGE WILL BUILD OVER THE SOUTHEAST GOING INTO THE
HOLIDAY WEEKEND...WHILE ANOTHER STORM SYSTEM MOVES ACROSS
THE WESTERN THIRD OF THE US.  EC MODEL STRONGER WITH WESTERN
SYSTEM AND MAY BRING A CHANCE OF STORMS TO WESTERN OKLAHOMA
BY SUNDAY...AS IT LIFTS NORTH INTO THE NORTHERN ROCKIES AND
PLAINS. OVERALL...THE HOLIDAY WEEKEND APPEARS MAINLY DRY AND VERY
WARM/HOT WITH BETTER CHANCES FOR STORMS ACROSS WESTERN OK. MODELS
SIGNAL A RETURN TO A NORTHWEST FLOW BY THE MIDDLE OF NEXT WEEK
WHICH MAY BRING BETTER CHANCES FOR STORMS DURING THE LAST DAYS OF
MAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK  85  65  90  67 /  10  10  10  10
HOBART OK         89  64  95  68 /  10  10  10  10
WICHITA FALLS TX  92  66  97  68 /  10  10  10  10
GAGE OK           89  62  93  62 /  10  10  10  10
PONCA CITY OK     83  65  90  68 /  10  10  10  10
DURANT OK         88  65  93  65 /  10  10   0  10

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&

$$

26/30




AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

 550 PM CDT TUE MAY 22 2012

.AVIATION...
ISOLATED CHANCE FOR A THUNDERSTORM THROUGH 03Z. OTHERWISE...VFR
EXPECTED. THERE IS AN OUTSIDE CHANCE THAT THE SEA BREEZE MAY
BECOME ACTIVE WEDNESDAY AFTERNOON AFTER 21Z. FOR NOW THE CHANCES
ARE 10 PERCENT AND WILL NOT MENTION IN THE FORECAST.

40

&&

.PREV DISCUSSION... /ISSUED 336 PM CDT TUE MAY 22 2012/

DISCUSSION...
SHRA AND A FEW TSRA HAVE FORMED EARLIER TODAY THAN YESTERDAY IN
MADISON...WALKER...SAN JACINTO AND LIBERTY COUNTIES AND SLIGHTLY
MORE COVERAGE AS WELL. HAVE NUDGED POPS UP AROUND THOSE AREAS FOR
THE REST OF THIS AFTERNOON AND INTO THE MID EVENING HOURS.
CONVECTIVE TEMPERATURES WERE MET AND UPSTREAM DISTURBANCE HELPED
THIS ALONG TODAY. STILL EXPECT TSRA TO BE MOSTLY DIURNAL AND
SHOULD DIMINISH AFTER SUNSET. HRRR REFLECTIVITY FIELD FORECASTS
AGREE WITH THIS ASSESSMENT AS WELL.

GALVESTON HIT 90F AT 1252PM WHICH TIED THE RECORD HIGH FOR TODAY.
COULD HAVE GONE A LITTLE HIGHER BUT WINDS SHIFTED ONSHORE WITH A
SEA BREEZE JUST A FEW HOURS EARLIER THAN EXPECTED TODAY.

AS SURFACE HIGH OVER NW GULF MOVES SLOWLY AWAY AND LEE TROUGH
DEVELOPS TOMORROW ONSHORE WINDS WILL INCREASE. PWATS REMAIN AROUND
NORMAL FOR MARCH-MAY VALUES. MEAN 1000-700MB SOUTHWESTERLY TO
SOUTHWESTERLY WINDS SHOULD INCREASE THE CAPPING INVERSION LEADING
TO A DRY SPELL FOR THE NEXT SEVERAL DAYS. GULF MOISTURE DOES NOT
LOOK TO BE FULLY TAPPED UNTIL SATURDAY MORNING BUT REMAINS TRAPPED
UNDERNEATH GIANT SUBSIDENCE INVERSION AS UPPER RIDGING TAKES HOLD
OVER THE EAST HALF OF THE COUNTRY. COULD SEE A FEW VERY LOW TOPPED
-SHRA AT TIMES IN THE EXTENDED PERIOD UNDER THE CAP BUT NOT
COVERAGE WOULD BE ISOLATED AT BEST AND AMOUNTS VERY VERY LOW SO
WILL LEAVE OUT MENTION OF PCPN IN THE EXTENDED. VERY LITTLE CHANGE
IN MAX TEMPS THE NEXT FEW DAYS WITH ONLY SOME VERY TINY MODERATION
AS LOW LEVEL HUMIDITY AND ONSHORE FLOW COMMENCES. MORNING LOWS TO
CLIMB A TAD AS RH INCREASES.

NOT BUYING GFS SOLUTION IN LONG RANGE OF LOOP-D-LOOPING SFC LOW
RETURNING FROM THE ATLANTIC...PREFER ECMWF LIKE SOLUTION OF
CONTINUING TROUGHING OUT THAT WAY. AS A WISE FCSTR ONCE SAID ABOUT
THE LONG RANGE TROPICS...IF IT AINT IN THE ECMWF YET I AINT
BELIEVING IT.  GOOD WORDS GENERALLY.  04

AVIATION...
TOOK OUT THE MENTION OF CB/PCPN FOR THIS AFTN WITH THE 18Z TAFS AS
THERE WAS SOME UNCERTAINTY CONCERNING THE START TIME TO THE DEVEL-
OPMENT. BUT IT LOOKS LIKE THINGS ARE GOING SOONER THAN EXPECTED SO
WILL LIKELY BE ADDING VCTS/CB IN THE TAFS VIA AMENDMENTS AS STORMS
APPROACH THE VARIOUS SITES. OTHERWISE STILL EXPECTING PCPN TO WANE
WITH THE LOSS OF DAYTIME HEATING. MOSTLY VFR OVERNIGHT WITH PATCHY
BR IN THE USUAL SPOTS (CXO/LBX). ONSHORE FLOW PATTERN EVOLVING THE
NEXT FEW DAYS COULD MAKE FOR A SLIGHTLY MORE ACTIVE SEABREEZE. 41

MARINE...
NOT A LOT OF CHANGES TO THE GOING FCST OF DEVELOPING ONSHORE WINDS
THE NEXT FEW DAYS. WIND SPEEDS/WAVE HEIGHTS NOT EXPECTED TO BE AT/
NEAR CAUTION/ADVISORY LEVELS UNTIL LATE WEDS AS THE PRESSURE GRAD-
IENT TIGHTENS IN RESPONSE TO THE NEXT SYSTEM DEEPENING ACROSS/OVER
THE CENTRAL PLAINS. AS THIS PATTERN IS PROGGED TO PERSIST THE REST
OF THE WEEK...WE COULD ALSO SEE WAVE HEIGHTS INCREASE STEADILY FOR
THIS SAME TIME FRAME. 41

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      67  92  68  91  71 /  30  10  10  10  10
HOUSTON (IAH)              70  90  70  90  73 /  20  10  10  10  10
GALVESTON (GLS)            76  86  76  86  78 /  10  10  10  10  10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&

$$

DISCUSSION...43
AVIATION/MARINE...40




AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

 336 PM CDT TUE MAY 22 2012

.DISCUSSION...
SHRA AND A FEW TSRA HAVE FORMED EARLIER TODAY THAN YESTERDAY IN
MADISON...WALKER...SAN JACINTO AND LIBERTY COUNTIES AND SLIGHTLY
MORE COVERAGE AS WELL. HAVE NUDGED POPS UP AROUND THOSE AREAS FOR
THE REST OF THIS AFTERNOON AND INTO THE MID EVENING HOURS.
CONVECTIVE TEMPERATURES WERE MET AND UPSTREAM DISTURBANCE HELPED
THIS ALONG TODAY. STILL EXPECT TSRA TO BE MOSTLY DIURNAL AND
SHOULD DIMINISH AFTER SUNSET. HRRR REFLECTIVITY FIELD FORECASTS
AGREE WITH THIS ASSESSMENT AS WELL.

GALVESTON HIT 90F AT 1252PM WHICH TIED THE RECORD HIGH FOR TODAY.
COULD HAVE GONE A LITTLE HIGHER BUT WINDS SHIFTED ONSHORE WITH A
SEA BREEZE JUST A FEW HOURS EARLIER THAN EXPECTED TODAY.

AS SURFACE HIGH OVER NW GULF MOVES SLOWLY AWAY AND LEE TROUGH
DEVELOPS TOMORROW ONSHORE WINDS WILL INCREASE. PWATS REMAIN AROUND
NORMAL FOR MARCH-MAY VALUES. MEAN 1000-700MB SOUTHWESTERLY TO
SOUTHWESTERLY WINDS SHOULD INCREASE THE CAPPING INVERSION LEADING
TO A DRY SPELL FOR THE NEXT SEVERAL DAYS. GULF MOISTURE DOES NOT
LOOK TO BE FULLY TAPPED UNTIL SATURDAY MORNING BUT REMAINS TRAPPED
UNDERNEATH GIANT SUBSIDENCE INVERSION AS UPPER RIDGING TAKES HOLD
OVER THE EAST HALF OF THE COUNTRY. COULD SEE A FEW VERY LOW TOPPED
-SHRA AT TIMES IN THE EXTENDED PERIOD UNDER THE CAP BUT NOT
COVERAGE WOULD BE ISOLATED AT BEST AND AMOUNTS VERY VERY LOW SO
WILL LEAVE OUT MENTION OF PCPN IN THE EXTENDED. VERY LITTLE CHANGE
IN MAX TEMPS THE NEXT FEW DAYS WITH ONLY SOME VERY TINY MODERATION
AS LOW LEVEL HUMIDITY AND ONSHORE FLOW COMMENCES. MORNING LOWS TO
CLIMB A TAD AS RH INCREASES.

NOT BUYING GFS SOLUTION IN LONG RANGE OF LOOP-D-LOOPING SFC LOW
RETURNING FROM THE ATLANTIC...PREFER ECMWF LIKE SOLUTION OF
CONTINUING TROUGHING OUT THAT WAY. AS A WISE FCSTR ONCE SAID ABOUT
THE LONG RANGE TROPICS...IF IT AINT IN THE ECMWF YET I AINT
BELIEVING IT.  GOOD WORDS GENERALLY.  04


.AVIATION...
TOOK OUT THE MENTION OF CB/PCPN FOR THIS AFTN WITH THE 18Z TAFS AS
THERE WAS SOME UNCERTAINTY CONCERNING THE START TIME TO THE DEVEL-
OPMENT. BUT IT LOOKS LIKE THINGS ARE GOING SOONER THAN EXPECTED SO
WILL LIKELY BE ADDING VCTS/CB IN THE TAFS VIA AMENDMENTS AS STORMS
APPROACH THE VARIOUS SITES. OTHERWISE STILL EXPECTING PCPN TO WANE
WITH THE LOSS OF DAYTIME HEATING. MOSTLY VFR OVERNIGHT WITH PATCHY
BR IN THE USUAL SPOTS (CXO/LBX). ONSHORE FLOW PATTERN EVOLVING THE
NEXT FEW DAYS COULD MAKE FOR A SLIGHTLY MORE ACTIVE SEABREEZE. 41

&&

.MARINE...
NOT A LOT OF CHANGES TO THE GOING FCST OF DEVELOPING ONSHORE WINDS
THE NEXT FEW DAYS. WIND SPEEDS/WAVE HEIGHTS NOT EXPECTED TO BE AT/
NEAR CAUTION/ADVISORY LEVELS UNTIL LATE WEDS AS THE PRESSURE GRAD-
IENT TIGHTENS IN RESPONSE TO THE NEXT SYSTEM DEEPENING ACROSS/OVER
THE CENTRAL PLAINS. AS THIS PATTERN IS PROGGED TO PERSIST THE REST
OF THE WEEK...WE COULD ALSO SEE WAVE HEIGHTS INCREASE STEADILY FOR
THIS SAME TIME FRAME. 41


&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      92  67  92  68  91 /  20  30  10  10  10
HOUSTON (IAH)              94  70  90  70  90 /  20  20  10  10  10
GALVESTON (GLS)            90  76  86  76  86 /  10  10  10  10  10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&

$$

DISCUSSION...04




AREA FORECAST DISCUSSION

NWS FORT WORTH TX

 100 PM CDT TUE MAY 22 2012

.AVIATION...
THE ONLY AVIATION WEATHER CONCERNS TODAY WILL ISOLATED SHOWERS
THIS AFTERNOON ASSOCIATED WITH A WEAK MCV...CURRENTLY WEST OF THE
TAF SITES. THE MCV WILL CONTINUE ON A SOUTHEAST TRACK AND A FEW
SHOWERS ON THE PERIPHERY OF THE CIRCULATION MAY GRAZE THE METROPLEX
TAF SITES WITH A SLIGHTLY BETTER CHANCE OF A BRIEF SHOWER AT WACO.
SINCE IMPACTS WITH ANY OF THESE ELEVATED SHOWERS SHOULD BE
MINIMAL...WILL NOT MENTION IN THIS TAF PACKAGE. ANY SHOWERS THAT
DO MANAGE TO FORM SHOULD DISSIPATE WITH THE LOSS OF SURFACE
HEATING.  EXPECT VFR CONDITIONS TONIGHT AND WEDNESDAY.

A SOUTH WIND WILL PREVAIL BETWEEN 5 AND 11 KNOTS THIS AFTERNOON
AND TONIGHT. SOUTHERLY WINDS WILL INCREASE SIGNIFICANTLY WEDNESDAY
AS SURFACE LOW PRESSURE DEEPENS ACROSS THE HIGH PLAINS. SUSTAINED
WIND SPEEDS WILL RANGE FROM 15 TO 20 MPH WITH SOME HIGHER GUSTS.


79

&&

.UPDATE...
THE WEAK SURFACE FRONT SITS NEAR A LINE FROM LEON TO STEPHENVILLE
TO BRYSON. 925 MB FLOW SHOWS WEAK CONVERGENCE NEAR THE
FRONT...WHICH BY THIS AFTERNOON SHOULD BE LOCATED NEAR A BOWIE TO
FORT WORTH TO PALESTINE LINE. MORNING MODELS SUCH AS HRRR AND NAM
AND GFS ARE A BIT MORE AGGRESSIVE DEVELOPING SOME CONVECTION ALONG
THIS LINE SO HAVE ADDED ISOLD POPS FARTHER EAST THAN PREVIOUS.
OTHERWISE...FEW CHANGES TO THE PACKAGE. 84

&&

.PREV DISCUSSION... /ISSUED 340 AM CDT TUE MAY 22 2012/
CIRRUS BLOWOFF FROM THE THUNDERSTORMS IN THE PANHANDLE AND SOUTH
PLAINS OF WEST TEXAS CONTINUE TO SPREAD SOUTHEAST ACROSS NORTH
TEXAS THIS MORNING. EXPECT THESE CLOUDS TO THIN LATER THIS
MORNING...AND WE SHOULD SEE TEMPERATURES CLIMB INTO THE MID 80S
NORTHEAST TO MID 90S SOUTH THIS AFTERNOON. AS A SHORTWAVE MOVES
SOUTHEAST OUT OF THE PANHANDLE...A FEW THUNDERSTORMS MAY AFFECT
THE WESTERN COUNTIES. THUS HAVE LEFT LOW POPS THERE. OTHERWISE...
IT LOOKS LIKE A WARM AND DRY PERIOD WILL OCCUR THROUGH THE
WEEKEND. AS A SURFACE TROUGH DEVELOPS ACROSS THE NORTHERN AND
CENTRAL PLAINS...WE WILL SEE SOUTHERLY WINDS INCREASE WEDNESDAY
AND THURSDAY. AN UPPER LEVEL RIDGE WILL DEVELOP ACROSS THE SOUTHEASTERN
UNITED STATES FRIDAY INTO THE WEEKEND. AS LOW LEVEL MOISTURE
INCREASES...CAN NOT RULE OUT SOME ISOLATED AFTERNOON/EARLY EVENING
THUNDERSTORMS SUNDAY AND MONDAY...BUT RAIN CHANCES ARE NOT HIGH
ENOUGH TO MENTION YET.

58



&&


.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX  91  69  93  71  95 /  10  10   5  10  10
WACO, TX              93  67  95  71  95 /  20  10   5  10  10
PARIS, TX             85  62  89  67  88 /   5   5   5  10  10
DENTON, TX            91  68  93  71  95 /  10  10   5  10  10
MCKINNEY, TX          90  66  92  70  92 /  10  10   5  10  10
DALLAS, TX            92  70  93  71  94 /  10  10   5  10  10
TERRELL, TX           88  66  92  69  93 /  10  10   5  10  10
CORSICANA, TX         91  67  92  70  93 /  10  10   5  10  10
TEMPLE, TX            92  66  93  70  94 /  20   5   5  10   5
MINERAL WELLS, TX     91  65  94  68  97 /  20  10   5  10  10

&&

.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

79/84






AREA FORECAST DISCUSSION

NWS BLACKSBURG VA

 100 PM EDT TUE MAY 22 2012

.SYNOPSIS...
A COLD FRONT SLOWLY PUSHES EAST ACROSS THE AREA THROUGH TONIGHT...AND
THEN TO THE COAST BY LATE WEDNESDAY. SHOWERS AND
THUNDERSTORMS...WITH SOME POTENTIALLY BRINGING HEAVY RAIN...WILL
BE POSSIBLE THROUGH THURSDAY. HIGH PRESSURE AND DRIER WEATHER WILL
ARRIVE LATE IN THE WEEK.
&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM EDT TUESDAY...

WEAK FRONT EDGING INTO THE FAR WESTERN SECTIONS THIS MORNING LOOKS
TO BE THE MAIN FOCUS FOR DEEPER AFTERNOON CONVECTION ESPCLY ACROSS
THE MOUNTAINS NEAR THE EDGE OF THE CLOUD CANOPY TO THE WEST ATTM.
LATEST MODIFIED MORNING RAOBS SHOW 1500-2K J/KG CAPES PROVIDED
ENOUGH HEATING THIS AFTERNOON UNDER LIGHT STEERING PER A MEAN
FLOW OF 6-10 KTS. THIS SHOULD AGAIN SPELL SLOW MOVING CLUSTERS OF
STORMS ESPCLY MOUNTAINS WITH A FEW OF THESE PERHAPS GOING SEVERE
WITH DOWNBURST POTENTIAL PER DECENT WINDEX VALUES...AND SOME HAIL
GIVEN LOW WET BULB VALUES OFF MORNING SOUNDINGS. HOWEVER WITH SUCH
A MID LEVEL CAP SEEN THIS MORNING MAY TAKE THINGS A LITTLE LONGER
TO DEVELOP WITH BETTER FOCUS LATER ON WEST AS THE UPPER LOW STARTS
TO LIFT NE ALONG THE SRN APPALACHIANS. THUS MAIN CHANGES WERE TO
SLOW DOWN ONSET OF CONVECTION THIS MORNING AND THEN INCREASE POPS
SOME WEST WHERE KEEPING HEAVY RAIN MENTION/WATCH IN PLACE. THIS
SUPPORTED BY EXPANSIVE COVERAGE OFF BOTH THE LATEST HRRR AND LOCAL
WRF MODELS AFTER MIDDAY INTO EARLY THIS EVENING. EXTENT OF TSRA
COVERAGE A BIT MORE IFFY E/SE GIVEN LESS SUPPORT AND MORE OUTFLOW
DRIVEN...BUT EXPECT HIGH CAPES AND EVENTUAL SPILLING OF WESTERN
CONVECTION TO SUPPORT LIKELY POPS THERE. RAISED HIGH TEMPS
SLIGHTLY ALONG THE BLUE RIDGE WHERE SHOULD SEE MORE SUN EARLY OTRW
70S WEST TO LOW 80S EAST APPEAR ON TRACK.

AS OF 615 AM EDT TUESDAY...

UPDATE TO DROP POPS SOME THIS MORNING GIVEN RADAR TRENDS. WILL
SEE INCREASE IN COVERAGE AGAIN OVER THE MTNS BY LATE MORNING.
DECREASED CLOUD COVERAGE EARLY AS WELL ESPECIALLY THE SRN CWA.

PREVIOUS DISCUSSION AT 355 AM...

ECHOES ON RADAR WEAKENING AS EXPECTED BUT NOT SURPRISED THAT
SHOWERS HAVE LINGERED ALL NIGHT...PER HIGHER THETA-E AIR AND
LINGERING BOUNDARIES AND UPPER SUPPORT. TODAY WILL BE ANOTHER
STORMY ONE FOR THE AREA AND EXPECT MORE COVERAGE OF SHOWERS AND
STORMS. GIVEN THE RAINFALL OVER THE MOUNTAINS THAT LAST FEW DAYS
AND LOWER FFG VALUES COMBINED WITH A PATTERN CONDUCIVE TO SLOW
MOVING STORMS AND HIGH PWATS...HAVE WENT AHEAD AN ISSUED A FLASH
FLOOD WATCH FOR AREAS ALONG AND WEST OF THE BLUE RIDGE.

THE FOCUS TODAY WILL BE ACROSS THE MOUNTAINS WHERE BEST UPPER
DIFFLUENCE IS EXPECTED WITH UPPER TROUGH. AT THE SFC...COLD FRONT
WILL BE EDGING EWD TO THE BLUE RIDGE BY EVENING WITH SEVERAL WEAK
LOWS MOVING ALONG IT. WITH EXTENSIVE CLOUD COVER...NOT EXPECT A
WIDESPREAD THREAT FOR SVR BUT WITH MOIST AIRMASS...AND COLDER AIR
ALOFT WITH THE UPPER TROUGH...WOULD NOT BE SURPRISED THAT SOME
STORMS BECOME STRONG TO SEVERE WITH ISOLATED LARGE HAIL/MICROBURST
THREAT. WINDS ALOFT ARE WEAK...SO WOULD HAVE TO BE ENOUGH RAIN
LOADING IN THE STORM TO BRING DAMAGING WINDS.

WILL HAVE HIGHER POPS THIS AFTERNOON WITH CATEGORICAL ACROSS THE
BLUE RIDGE AND WEST. WITH MOIST AIRMASS AND LESS SUN WILL SEE HIGHS
IN BETWEEN THE COOLER MET/WARMER MAV...ALTHOUGH COOLER MET MAY HAVE
A BETTER IDEA. THE LOCAL MOS IN BETWEEN THE TWO SEEMS TO BE A BETTER
CHOICE...GIVEN SOME POTENTIAL FOR SUN. WITH THAT IN MIND...HIGHS
WILL RANGE FROM THE LOWER 80S SOUTHEAST TO THE LOWER 70S IN THE
SOUTHWEST WHERE STORMS ARRIVE/DEVELOP SOONER.


TONIGHT...THE HEAVY RAIN THREAT SHOULD DIMINISH OVERNIGHT AS ONE
AREA OF LIFT PUSHES OUT OF THE AREA. HOWEVER...MODELS SOLUTIONS ARE
CONVERGING TOWARD ANOTHER ORGANIZED AREA OF SHOWERS/STORMS OVER SW
VA AFTER MIDNIGHT...SO IF TRENDS CONTINUE TO SHOW THIS...MAY HAVE TO
EXTEND THE FFA FURTHER IN TIME...AS IT RUNS TIL MIDNIGHT FOR NOW.
LOWS TONIGHT WILL BE MILD AGAIN WITH LOWER TO MID 60 EAST TO MID 50S
WEST.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 355 AM EDT TUESDAY...

NOT TOO MUCH CHANGES THIS PERIOD...WITH UPPER TROUGH LINGER OVER THE
AREA...AND SFC FRONT EAST OF THE FORECAST AREA. PATTERN STILL WILL
REMAIN CONDUCIVE FOR SHOWER/STORM DEVELOPMENT ESPECIALLY IN THE
AFTN. MODELS ARE CONVERGING AGAIN ON THE NORTHERN FORECAST AREA TO
SEE MORE RAINFALL...AND KEPT POPS IN THE LIKELY RANGE ACROSS THIS
AREA....WITH HIGH CHANCE SOUTH TO THE NC/VA COUNTIES. HIGHER PWATS
WILL RESIDE OVER THE ERN CWA. AGAIN LOOKING AT MOSTLY CLOUD SKIES
ALL DAY WHICH IS GOING TO LIMIT HEATING AND THE SVR THREAT SHOULD
STAY ISOLATED...WITH HAIL POSSIBLE GIVEN UPPER COOL POOL OVER NC.

EXPECT TO SEE POPS TAPER OFF THE LOW CHANCE TO LESS THAN 20 PERCENT
WEST OF THE BLUE RIDGE AFTER MIDNIGHT WED NIGHT PER UPPER LOW
SHIFTING EAST INTO THE VA PIEDMONT.

THURSDAY LOOKS DRIER...BUT ANOTHER UPPER TROUGH SHIFTS FROM THE
TENNESSEE VALLEY INTO GEORGIA AND UPPER FLOW AND
DIVERGENCE...COMBINED WITH MODEST INSTABILITY SHOULD LEAD TO MORE OF
A SCATTERING OF SHOWERS AND STORMS.

SHOWERS AND STORMS SHOULD START TO WEAKEN THURSDAY NIGHT WITH LOSS
OF HEATING.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 305 PM EDT MONDAY...

THE MEDIUM RANGE MODELS AND ENSEMBLES ARE IN GOOD AGREEMENT
BUILDING A STRONG UPPER RIDGE...FIRST OVER THE OHIO VALLEY...THEN
ELONGATING INTO THE MID-ATLANTIC REGION SUNDAY INTO MONDAY. THIS
WILL RESULT IN TEMPERATURES WELL ABOVE NORMAL AND LESS COVERAGE IN
PRECIPITATION.

ON FRIDAY...THE LINGERING UPPER LEVEL TROF FINALLY GETS PUSHED
NORTHEAST BY A SHORTWAVE MOVING THROUGH THE GREAT LAKES. WITH A
MOIST (GREATER THAN 1.5 PWATS) AND UNSTABLE AIR MASS IN PLACE AND
WEAK LOW LEVEL CONVERGENCE AND THE SFC...WIDELY SCATTERED
THUNDERSTORMS WILL AGAIN BE POSSIBLE.

THE COVERAGE OF SHOWERS AND STORMS SHOULD DIMINISH THROUGH THE
HOLIDAY WEEKEND AS THE UPPER RIDGE BUILDS. HOWEVER...WEAK...BUT
FAIRLY DEEP EAST/SOUTHEAST UPSLOPE LOW LEVEL FLOW MAY BE ABOVE TO
OVERCOME WARMING MID LEVEL TEMPS/RISING HEIGHTS TO INITIATE ISOLATED
TO WIDELY SCT STORMS ALONG THE BLUE RIDGE.

LEARNED TOWARD THE WARMER MEX GUIDANCE FOR TEMPS THROUGH THE LONG
TERM PERIOD...WITH FORECAST HIGHS NEARING RECORDS FOR BLF.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 1245 PM EDT TUESDAY...

MVFR CIGS ACROSS THE WEST FINALLY STARTING TO MIX OUT WITH
HEATING...OTRW WILL CONTINUE VFR TRENDS OUTSIDE OF CONVECTION
INTO LATE THIS AFTERNOON. CURRENT TSRA FORMING ON THE
RIDGES...MAINLY OUTSIDE OF THE TAF SITES...BUT CLOSE ENOUGH
PROXIMITY TO INCLUDE A VCTS AT KROA AND KLWB TO INIT. ELSW DELAYED
COVERAGE A BIT BUT APPEARS AREAS ALONG/WEST OF THE BLUE RIDGE WILL
START TO FILL IN WITH SHRA/TSRA GIVEN ADDED HEATING/OUTFLOW SO
INCLUDING AT LEAST A VCSH OR VCTS MENTION MOST LOCATIONS FROM MID
AFTERNOON INTO EARLY THIS EVENING. TSRA WILL AGAIN BE SLOW MOVING
WITH POTENTIAL FOR ANY LOCATION TO QUICKLY LOWER TO IFR IN HEAVY
RAINFALL AND LOWER CIGS. WINDS WILL REMAIN MOSTLY LIGHT AND VRBL
BUT COULD GUSTS TO ABOVE 30-40 MPH NEAR ANY OF THE STORMS.

WILL STILL SEE SOME COVERAGE OF CONVECTION HEADING INTO THE
EVENING BUT SHOULD BE LESS...SO ONLY EXTENDED END TIME OUT AN HOUR
OR TWO TO COVER POTENTIAL UNTIL SHORTLY AFTER SUNSET. AGAIN WILL
BE A NIGHT SIMILAR TO LAST NIGHT WHERE CIGS/VSBYS COULD FLUCTUATE
BETWEEN LIFR TO VFR AT TIMES...SO WENT TOWARD MIDDLE ROUTE OF
IFR...MAINLY WITH FOG INSTEAD OF LOWER CIGS. ANY LOCATION THAT
DOES SEE HEAVY RAIN COULD DROP INTO LIFR AFTER MIDNIGHT AND NOT
SEE MUCH IMPROVEMENT UNTIL MID MORNING WEDNESDAY.

WEDNESDAY WILL BE A REPEAT OF TODAY WITH MOST COVERAGE OF STORMS
SHIFTING NORTH OF A LINE FROM BLF-LYH. MAINLY VFR AFTER MORNING
FOG/LOWER CLOUDS EXCEPT IN HEAVIER TSRA.

LOOKING AT THE PATTERN SHIFTING TOWARD THE END OF THE WEEK...AND
UNTIL FRIDAY SHOULD SEE NIGHTTIME THREAT OF LOWER CIGS/FOG AND
DAYTIME THUNDER. BY FRIDAY WILL SEE HIGH PRESSURE WORKING IN TO
BRING VFR WX...AND TEMPERATURES HEAT UP. NIGHLTY FOG IN THE
VALLEYS BCB/LWB A GOOD POSSIBILITY GIVEN THE GROUND SHOULD BE
MOIST...WITH LITTLE WIND.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR VAZ007-
     009>020-022>024.
NC...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR NCZ001-002-
     018.
WV...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR WVZ042>045.

&&

$$
SYNOPSIS...JH/PW/WP
NEAR TERM...JH/WP
SHORT TERM...PH/WP
LONG TERM...PH
AVIATION...JH/WP








AREA FORECAST DISCUSSION

NWS GREEN BAY WI

 534 PM CDT TUE MAY 22 2012

UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE

.SHORT TERM...TONIGHT AND WEDNESDAY.

THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH
PRESSURE STRETCHING FROM THE SOUTHERN GREAT PLAINS AND ACROSS THE
CENTRAL GREAT LAKES TO HUDSON BAY. A WARM FRONT HAS BEEN
DEVELOPING TODAY OVER THE FAR NORTHERN PLAINS AND OVER WESTERN
LAKE SUPERIOR TO THE UPPER PENINSULA. WARM/MOIST ADVECTION NORTH
OF THE BOUNDARY IS CONTRIBUTING TO SCT LIGHT SHOWERS AND ISOLATED
THUNDERSTORMS FROM NORTHERN MINNESOTA TO THE WESTERN UPPER
PENINSULA. SOME RETURNS ARE GRAZING THE U.P. BORDER THIS
AFTERNOON...BUT NO CONFIRMATION OF THESE RETURNS REACHING THE
GROUND AT IRONWOOD OR LAND O LAKES. THE AIRMASS IS PRETTY DRY IN
THIS AREA WITH DEWPOINTS AT LAND O LAKES IN THE LOWER 30S. AS LOW
PRESSURE OVER WESTERN NORTH DAKOTA MOVES NORTHEAST...A COLD FRONT
WILL MOVE TO THE UPPER MISSISSIPPI VALLEY TOMORROW. WITHOUT MUCH
IMPACT YET...CLOUDS AND TEMPS WILL BE THE MAIN FORECAST CONCERNS.

TONIGHT...HIGH PRESSURE OVER THE CENTRAL GREAT LAKES TO START THE
EVENING WILL SHIFT TO THE EASTERN GREAT LAKES OVERNIGHT. LOW
PRESSURE WILL MOVE NORTHEAST OVER THE PLAINS TONIGHT...BUT ITS
WARM FRONT WILL REMAIN RELATIVELY STATIONARY OVER THE SOUTH
SHORELINE OF LAKE SUPERIOR. WARM/MOIST ADVECTION THAT IS OCCURRING
OVER THE ARROWHEAD OF MINNESOTA AND THE UPPER PENINSULA WILL BE
LIFTING OFF TO THE NORTHEAST GRADUALLY AS HEIGHTS BUILD
ALOFT...EVEN THOUGH CORFIDI VECTORS TRACK THE INDIVIDUAL SHOWERS
OFF TO THE SOUTHEAST. THINK THERE IS POTENTIAL FOR THIS SHOWER
ACTIVITY TO GRAZE THE U.P.-WISCONSIN BORDER THROUGH 00Z.
HOWEVER...LOW LEVELS ARE VERY DRY...SO WILL LEAVE IT AS A CHANCE
OF SPRINKLES. RECENT RADAR TRENDS ALREADY SHOW THE BACK EDGE OF
THE PRECIP LIFTING NE OVER THE ARROWHEAD...SO AM COUNTING ON THIS
TREND KEEPING THE BORDER DRY AFTER 00Z. MID AND UPPER CLOUDS WILL
BE LIFTING OFF TO THE NE AS WELL SO SHOULD SEE DECREASING CLOUDS
THROUGH THE NIGHT OVER THE NORTH. THE PRESSURE GRADIENT WILL BE
TIGHTENING TONIGHT...WHICH WILL KEEP LOWS WARMER THAN LAST NIGHT.
WILL GO WITH MID TO UPPER 40S FOR LOWS.

WEDNESDAY...UPSTREAM COLD FRONT WILL MOVE INTO THE NORTHERN
MISSISSIPPI VALLEY DURING THE AFTERNOON. WITH THE AREA FIRMLY IN
THE WARM SECTOR...WILL HAVE MID AND UPPER CLOUDS NORTH AND WEST OF
THE REGION...BUT SHOULD SEE MOSTLY CLEAR TO PARTLY CLOUDY SKIES
FOR THE DAY. THE PRESSURE GRADIENT WILL TIGHTEN AHEAD OF THE
FRONT...AND SOUTH WINDS WILL TURN GUSTY WITH DAYTIME HEATING AND
MIXING. SOME GUSTS COULD REACH 30 OR MAYBE EVEN 35 MPH. HIGHS
TOMORROW IN THE MID 70S TO LOW 80S.

.LONG TERM...WEDNESDAY NIGHT THROUGH NEXT TUESDAY. ONE OF THE
FORECAST CHALLENGES FOR THIS PERIOD IS TRYING TO LASSO IN THE
LOCATIONS OF THE FRONT FOR THE MEMORIAL DAY WEEKEND. ANOTHER ISSUE
IS TIMING AND STRENGTH OF A SHORT WAVE TROUGH FOR LATER THURSDAY
AND ESPECIALLY THURSDAY NIGHT.

LITTLE CHANGE FROM THE GOING FORECAST FROM 24 HOURS AGO FROM
WEDNESDAY NIGHT INTO THURSDAY AS A SURFACE HIGH PRESSURE WITH
UPPER RIDGE DRIFTING OVER THE AREA WILL CONTINUE TO PROVIDE QUIET
WEATHER TO THE AREA. MODELS CONTINUE TO CONFINE CONVECTION OVER
THE NORTHERN PLAINS WITH THE BROAD UPPER TROUGH. PWATS GRADUALLY
INCREASE TO 1.75 ALONG THE FRONT OVER THE NORTHERN PLAINS. UNTIL
THIS UPPER RIDGE IS NUDGED FAR ENOUGH EAST...WILL CONTINUE TO
CONFINE ANY SMALL PCPN MENTION AND CLOUDS WEST OF A RHI TO AUW
LINE.

WILL THEN FOCUS ON HIGHER POPS FOR THE THURSDAY AFTERNOON INTO
THURSDAY NIGHT PERIOD AS A SHORT WAVE SLIDES OVER THE STATE. A
SURFACE LOW AND UPPER JET COUPLET PROGGED TO AFFECT THE NORTH HALF
OF THE STATE DURING THIS PERIOD PROVIDES SOME POTENTIAL OF STRONG
TO SEVERE STORMS. PROGS ARE A BIT MORE PROGRESSIVE WITH THE
FRONTAL PASSAGE LATE THURSDAY NIGHT. USING THE H8 FRONT...THE
FRONT IS DRIVEN SOUTH OF THE AREA FRIDAY INTO FRIDAY NIGHT FOR A
DIMINISHED PERIOD OF CONVECTION. PROGS IN GOOD AGREEMENT WITH H8
WARM FRONT LIFTING BACK NORTH AGAIN ON SATURDAY SO INCREASED
CONVECTION INCLUDING THUNDER FROM SOUTH TO NORTH DURING THE DAY.
PROGS CONTINUE TO LIFT THE FRONT NORTH TO GRADUALLY DIMINISH
CONVECTION OVER CENTRAL AND EAST CENTRAL WISCONSIN BUT WILL
CONFINE BEST PCPN CHANCES ACROSS THE NORTH SUNDAY AND PERHAPS INTO
MONDAY CLOSER TO THE WARM FRONT. AREAS TO THE SOUTH LIKELY TO BE
CAPPED IN A VERY WARM HUMID AIR MASS AS UPPER HEIGHTS BUILD.
ANOTHER FRONT IS PROGGED TO SLIDE OVER MONDAY INTO MONDAY NIGHT
FOR ANOTHER SHOT OF CONVECTION. PWATS INCREASE TO 1.70 INCHES
ALONG THE FRONT...HOWEVER AT THIS TIME IT APPEARS THE FRONTS ARE A
LITTLE TOO PROGRESSIVE FOR HEAVY RAINS TO CONCENTRATE IN ANY ONE
LOCATION WITH THE EXCEPTION OF THE FAR NORTH NEAR THE WARM FRONT.
&&

.AVIATION...FOR 00Z TAF ISSUANCE. VFR CONDITIONS EXPECTED TNGT AND
WED AS SFC RIDGE SLIDES AWAY TO THE SE AND FRONTAL SYSTEM STARTS
TO ADVANCE E FM THE PLAINS. MAIN FCST ISSUE IS LLWS POTENTIAL
TNGT. RAP CONSIDERABLY STRONGER WITH WINDS 1-2K FT IN C/N-C WI THAN
THE NAM...AND THE NAM IS NORMALLY ON THE HIGH END OF THE GUID WITH
LOW-LEVEL WINDS. CONSIDERABLE SPREAD AMONG SREF MEMBERS AS
WELL. OVERALL...SREF SEEMS TO LEND ENOUGH SUPPORT TO INCLUDE
LLWS IN THE WRN TAF SITES...BUT AS LEVELS BLO THOSE SHOWN ON RAP
FCST SOUNDINGS.

SKOWRONSKI
&&

.MARINE...A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED LATE
WEDNESDAY AFTERNOON INTO THURSDAY NIGHT. INCREASING SOUTH WINDS
ARE EXPECTED ON WEDNESDAY...THEN STRONG SOUTH WINDS ARE EXPECTED
ON THURSDAY. A FEW GUSTS COULD APPROACH GALE FORCE NEAR THE
SHORELINE THURSDAY AFTERNOON. WINDS AND WAVES WILL GRADUALLY
SUBSIDE THURSDAY NIGHT.

FOR THE UPCOMING MEMORIAL DAY WEEKEND...IT WILL BE UNSETTLED AS
THERE WILL BE CHANCES FOR THUNDERSTORMS EACH DAY. A WARM FRONT IS
EXPECTED TO SLOWLY PUSH NORTHWARD INTO THE AREA OVER THE WEEKEND.
THERE IS A LOT OF UNCERTAINTY ON HOW FAR NORTH THE WARM FRONT WILL
MAKE IT INTO NORTHEAST WISCONSIN AND WHERE THE BEST CHANCES FOR
THUNDERSTORMS WOULD OCCUR.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$







AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 303 PM CDT TUE MAY 22 2012

.SHORT TERM...TONIGHT THROUGH FRIDAY
303 PM CDT TUE MAY 22 2012

MAIN FORECAST CONCERNS ARE WHEN PRECIPITATION CHANCES MOVE INTO THE
AREA AND SEVERE WEATHER POTENTIAL FOR THURSDAY.

CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED TROUGHING OVER SOUTHWEST CANADA AND THE NORTHERN ROCKIES...
WITH RIDGING BUILDING DOWNSTREAM OVER THE UPPER MISSISSIPPI RIVER
VALLEY REGION. A SHORTWAVE EJECTING OUT OF THE TROUGHING AND
DOWNSLOPING UPPER FLOW OFF THE ROCKIES HAS LED TO LOW PRESSURE
DEVELOPMENT OVER THE DAKOTAS. INCREASING SOUTHERLY FLOW DOWNSTREAM
OF THIS SURFACE LOW ON THE ORDER OF 20-40KT 850MB WINDS PER PROFILER
DATA IS SPREADING WARMER AIR NORTHWARD. MODIFYING THROUGH ADVECTION
AND DAYTIME HEATING PROCESSES FROM 12Z RAOBS...THE RAP SUGGESTS
850MB TEMPS HAVE RISEN TO 10-14C OVER THE FORECAST AREA. WITH PLENTY
OF SUN AND THE INCREASING WINDS...SURFACE TEMPERATURES HAVE CLIMBED
INTO THE 70S TO LOW 80S. FARTHER WEST...THE 850MB TEMPS INCREASE TO
18-25C OR HIGHER OVER MUCH OF THE PLAINS. MOISTURE IS ALSO
RETURNING...MORE OVER THE PLAINS...WHERE SURFACE DEWPOINTS ARE
MOSTLY IN THE 50S.

TONIGHT AND WEDNESDAY...TROUGHING OVER THE NORTHERN ROCKIES IS
FORECAST TO DEEPEN ACROSS THE WESTERN U.S....RESULTING IN
STRENGTHENING RIDGING DOWNSTREAM INTO THE GREAT LAKES. A COUPLE OF
SHORTWAVES EJECTING OUT OF THIS TROUGHING WILL HELP LIFT THE LOW IN
THE DAKOTAS INTO FAR NORTHWEST ONTARIO...DRAGGING A COLD FRONT INTO
WESTERN MINNESOTA BY 00Z. INCREASING SOUTH TO SOUTHWEST FLOW ALOFT
AHEAD OF THE FRONT WILL HELP BRING WARMER AIR INTO THE FORECAST AREA
WITH 850MB TEMPS CLIMBING TO AT LEAST 16-18C BY 18Z WEDNESDAY. WE
SHOULD ALSO SEE AN INCREASE IN ALTOSTRATUS AND CIRROSTRATUS...
ALREADY EVIDENT OVER EASTERN MONTANA AND WYOMING. THESE CLOUDS MAY
TEMPER HIGHS SOMEWHAT...BUT READINGS SHOULD EASILY REACH INTO THE
80S GIVEN THE STRENGTH OF THE WARM ADVECTION/WINDS AND SUN. LOWS
TONIGHT ALSO EXPECTED TO BE WARMER WITH THE INCREASING WINDS...
ESPECIALLY ACROSS SOUTHEAST MINNESOTA. REGARDING PRECIPITATION
CHANCES...ANY CONVECTION SHOULD BE STRONGLY TIED TO THE FRONT. AHEAD
OF THE FRONT...MODELS SUGGEST QUITE A BIT OF CIN...EVEN WITH THEIR
HIGHER SURFACE DEWPOINTS LIKE THE NAM SUGGESTS. THERE IS ALSO MIX
DOWN POTENTIAL OF THE DEWPOINTS WITH PLENTIFUL DRY AIR BELOW 700MB.
THEREFORE...THINKING THE ENTIRE FORECAST AREA SHOULD BE DRY THROUGH
WEDNESDAY. LAST ITEM OF NOTE IS WINDS COULD GET CLOSE TO ADVISORY
CRITERIA IN SOUTHEAST MN LATE IN THE MORNING INTO MID AFTERNOON...
JUST BASED ON THE SPEEDS THEMSELVES. SOMETHING TO WATCH.

WEDNESDAY NIGHT AND THURSDAY...AT THE BASE OF THE DEEPENING WESTERN
TROUGH...A NEW SURFACE LOW SHOULD HAVE DEVELOPED OVER FAR SOUTHEAST
COLORADO BY 00Z THURSDAY. THIS SURFACE LOW IS EXPECTED TO LIFT
NORTHEAST...ALONG THE COLD FRONT THAT MOVED INTO WESTERN MINNESOTA
LATE WEDNESDAY...DUE TO ANOTHER COLLECTION OF SHORTWAVES EJECTING
OUT OF THE WESTERN TROUGH. THEREFORE...THE FRONT WEDNESDAY NIGHT IS
LIKELY TO NOT MAKE MUCH IF ANY PROGRESS EASTWARD. IN FACT...WE NEED
TO WAIT UNTIL THE LOW MOVES NORTH OF THE AREA TO DRIVE THE COLD
FRONT EASTWARD. THIS DRIVE EASTWARD TOO WILL BE ENHANCED BY A FAIRLY
POTENT SHORTWAVE COMING UP INTO MINNESOTA. FOR WEDNESDAY NIGHT...
AGAIN CONVECTION SHOULD REMAIN TIED AROUND THE COLD FRONT IN
MINNESOTA. VARIOUS THINGS GOING FOR CONVECTION INCLUDE A RIGHT
ENTRANCE REGION OF A JET LIFTING OUT OF THE DAKOTAS...INCREASING LOW
TO MID-LEVEL FRONTOGENESIS ON THE COLD FRONT...AND A PLUME OF
500-1000 J/KG OF MUCAPE BEING TRANSPORTED INTO THE FRONTOGENESIS
ZONE BY A STRENGTHENING LOW LEVEL JET. AS IT STANDS RIGHT NOW...MOST
MODELS SUGGEST THE FRONT AND BULK OF CONVECTION WILL END UP WEST OF
THE FORECAST AREA. HAVE MAINTAINED SOME CHANCES OVER THE NORTHWEST
ENDS...THOUGH...AS CONVECTIVE OUTFLOWS MAY TRY TO PUSH THE FRONT
EASTWARD. THURSDAY IS DEFINITELY MORE CONCERNING AS THE POTENT
SHORTWAVE APPROACHES IN THE AFTERNOON. SOME SLIGHT TIMING
DIFFERENCES EXIST ON THE COLD FRONTAL PASSAGE AND APPROACH OF THE
SHORTWAVE...BUT THERE IS GOOD AGREEMENT THAT THE DYNAMICAL AND
THERMODYNAMICAL FORCING WILL LIKELY LEAD TO A SQUALL LINE ALONG THE
FRONT EARLY TO MID AFTERNOON...ALONG WITH POST-FRONTAL
PRECIPITATION. THIS PRECIPITATION THEN PUSHES EAST INTO THE EVENING.
RAISED PRECIPITATION CHANCES TO 50-70 FOR THE AFTERNOON. PLENTIFUL
0-6 KM AND 0-3KM SHEAR AND MLCAPE OF 500-1000 J/KG SHOULD BE ENOUGH
TO PRODUCE SOME SEVERE WEATHER...WITH DAMAGING WINDS MAIN HAZARD.
TEMPERATURES LIKELY TO STAY WARM WEDNESDAY NIGHT AND THURSDAY DUE TO
BREEZY WINDS...WITH A POSSIBLE FALL IN TEMPERATURES IN THE AFTERNOON
AS THE FRONT/PRECIPITATION MOVE THROUGH. WINDS COULD GET CLOSE TO
ADVISORY CRITERIA ON THURSDAY.

THURSDAY NIGHT AND FRIDAY...AFTER THE SQUALL LINE AND COLD FRONT
MOVE THROUGH IN THE EVENING...STRONG SUBSIDENCE IS INDICATED TO MOVE
INTO THE FORECAST AREA. RAISED PRECIPITATION CHANCES EAST OF THE
MISSISSIPPI RIVER TO 50-70 TO HANDLE THE SQUALL LINE. CONDITIONS
SHOULD THEN DRY OUT AFTER MIDNIGHT THANKS TO THE SUBSIDENCE...
PRODUCED MOSTLY BY THAT POTENT SHORTWAVE WHICH LIFTS INTO UPPER
MICHIGAN. THE COLD FRONT LOOKS TO STALL OVER NORTHERN MISSOURI
FRIDAY MORNING. NEW DEEPER TROUGHING THEN FORMS IN THE WESTERN
U.S....CAUSING RIDGING TO RE-BUILD DOWNSTREAM INTO THE
MID-MISSISSIPPI VALLEY. DEPENDING ON THIS TIMING OF THE RIDGING
BUILDING UP...THE FRONT MAY START MOVING BACK NORTH IN THE
AFTERNOON...AS INDICATED IN THE 22.12Z NAM/GEM. MOISTURE TRANSPORT
OVER THIS FRONT COULD LEAD TO A FEW SHOWERS AND THUNDERSTORMS OVER
NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN...THOUGH DEFINITELY
BETTER CHANCES WOULD BE OVER SOUTHERN IOWA CLOSER TO THE FRONT.
COOLER AIR ADVECTING IN BEHIND THE FRONT SHOULD HELP SEND
TEMPERATURES BACK DOWN TO SEASONABLE LEVELS.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
303 PM CDT TUE MAY 22 2012

MODELS AND GFS ENSEMBLES ARE INCREASINGLY BECOMING IN GOOD AGREEMENT
FOR THE WEEKEND...INDICATING TROUGHING TO PERSIST OVER THE WESTERN
U.S. WHILE STRONG SUBTROPICAL RIDGING BUILDS OVER THE EASTERN TWO
THIRDS OF THE COUNTRY. WITH THIS BUILDING RIDGING...THE WARM FRONT
ON FRIDAY SITUATED EITHER OVER SOUTHERN IOWA OR NORTHERN MISSOURI
WILL GRADUALLY LIFT NORTH ACROSS THE FORECAST AREA. THE SPEED OF
THIS MAY BE MODULATED BY PERIODS OF CONVECTION FORMING ON THE WARM
FRONTAL BOUNDARY...IN RESPONSE TO FRONTOGENESIS AND ESPECIALLY
INCREASING LOW LEVEL JET/MOISTURE TRANSPORT AT NIGHT. BEST TIME
PERIOD FOR CONVECTION ACROSS THE AREA WOULD PROBABLY BE FRIDAY NIGHT
INTO SATURDAY MORNING. SATURDAY NIGHT INTO SUNDAY MORNING COULD
OCCUR TOO OVER FAR NORTHERN PORTIONS OF THE AREA...DEPENDING ON HOW
FAR NORTH THE WARM FRONT REACHES. EITHER ROUND OF CONVECTION COULD
BE SEVERE...GIVEN 1-6 KM SHEAR VALUES OF 40KT OR MORE AND LIKELY
PLENTY OF INSTABILITY BEING ADVECTED OVER THE FRONTAL ZONE. ONCE THE
WARM FRONT PASSES...850MB TEMPS JUMP TO 20C OR HIGHER. SUNDAY LOOKS
TO BE THE WARM DAY WITH TEMPERATURES LIKELY WELL INTO THE
80S...PERHAPS EVEN 90S.

THINGS GET A LITTLE MORE MURKY FOR EARLY NEXT WEEK...IN PARTICULAR
WITH THE HANDLING OF THE WESTERN TROUGH. THE 22.00Z/22.12Z ECMWF/GEM
AND SOME OF THE 22.12Z GFS ENSEMBLES SUGGEST THE WESTERN TROUGH WILL
BE SLOWER TO EJECT NORTHEASTWARD THAN THE 22.12Z GFS AND THE REST OF
ITS ENSEMBLES. THIS SEEMS REASONABLE GIVEN THE STRENGTH OF THE
RIDGING AHEAD OF THE TROUGH. THEREFORE...LIKELY THE COLD FRONT
ASSOCIATED WITH THE TROUGH WILL BE SLOWER TO MOVE THROUGH THE
FORECAST AREA. THIS RESULTS IN A WARMER DAY ON MONDAY THAN WHAT
THE GFS WOULD SUGGEST. TUESDAY WOULD BE COOLER AFTER THE FRONTAL
PASSAGE. DID MAINTAIN THE CONSENSUS APPROACH FOR PRECIPITATION
CHANCES MONDAY THROUGH TUESDAY...GIVEN THE DIFFERENCES.

&&

.AVIATION...THROUGH 18Z WEDNESDAY
1233 PM CDT TUE MAY 22 2012

MAIN CONCERN THROUGH THE PERIOD WILL BE INCREASING SOUTH
WINDS...ESPECIALLY DURING THE DAY WEDNESDAY AS A LOW AND COLD
FRONT APPROACH FROM THE NORTHERN PLAINS. SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE SEEN ALONG AND AHEAD OF THIS APPROACHING
FRONT...BUT ARE EXPECTED TO REMAIN WEST OF THE FORECAST AREA. PLAN
ON SOME MID/HIGH LEVEL CLOUD DEBRIS FROM THIS SCATTERED CONVECTION
TO DRIFT OVER THE KRST/KLSE TAF SITES...OTHERWISE VFR CONDITIONS
WILL PREVAIL TONIGHT THROUGH MIDDAY WEDNESDAY.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
303 PM CDT TUE MAY 22 2012

WI...NONE.
MN...NONE.
IA...NONE.

&&

$$

SHORT TERM...AJ
LONG TERM...AJ
AVIATION...DAS







AREA FORECAST DISCUSSION

NWS GREEN BAY WI

 243 PM CDT TUE MAY 22 2012

.SHORT TERM...TONIGHT AND WEDNESDAY.

THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH
PRESSURE STRETCHING FROM THE SOUTHERN GREAT PLAINS AND ACROSS THE
CENTRAL GREAT LAKES TO HUDSON BAY.  A WARM FRONT HAS BEEN DEVELOPING
TODAY OVER THE FAR NORTHERN PLAINS AND OVER WESTERN LAKE SUPERIOR TO
THE UPPER PENINSULA.  WARM/MOIST ADVECTION NORTH OF THE BOUNDARY IS
CONTRIBUTING TO SCT LIGHT SHOWERS AND ISOLATED THUNDERSTORMS FROM
NORTHERN MINNESOTA TO THE WESTERN UPPER PENINSULA.  SOME RETURNS ARE
GRAZING THE U.P. BORDER THIS AFTERNOON...BUT NO CONFIRMATION OF
THESE RETURNS REACHING THE GROUND AT IRONWOOD OR LAND O LAKES.  THE
AIRMASS IS PRETTY DRY IN THIS AREA WITH DEWPOINTS AT LAND O LAKES IN
THE LOWER 30S.  AS LOW PRESSURE OVER WESTERN NORTH DAKOTA MOVES
NORTHEAST...A COLD FRONT WILL MOVE TO THE UPPER MISSISSIPPI VALLEY
TOMORROW.  WITHOUT MUCH IMPACT YET...CLOUDS AND TEMPS WILL BE THE
MAIN FORECAST CONCERNS.

TONIGHT...HIGH PRESSURE OVER THE CENTRAL GREAT LAKES TO START THE
EVENING WILL SHIFT TO THE EASTERN GREAT LAKES OVERNIGHT.  LOW
PRESSURE WILL MOVE NORTHEAST OVER THE PLAINS TONIGHT...BUT ITS WARM
FRONT WILL REMAIN RELATIVELY STATIONARY OVER THE SOUTH SHORELINE OF
LAKE SUPERIOR.  WARM/MOIST ADVECTION THAT IS OCCURRING OVER THE
ARROWHEAD OF MINNESOTA AND THE UPPER PENINSULA WILL BE LIFTING OFF
TO THE NORTHEAST GRADUALLY AS HEIGHTS BUILD ALOFT...EVEN THOUGH CORFIDI
VECTORS TRACK THE INDIVIDUAL SHOWERS OFF TO THE SOUTHEAST.  THINK
THERE IS POTENTIAL FOR THIS SHOWER ACTIVITY TO GRAZE THE
U.P.-WISCONSIN BORDER THROUGH 00Z.  HOWEVER...LOW LEVELS ARE VERY
DRY...SO WILL LEAVE IT AS A CHANCE OF SPRINKLES.  RECENT RADAR
TRENDS ALREADY SHOW THE BACK EDGE OF THE PRECIP LIFTING NE OVER THE
ARROWHEAD...SO AM COUNTING ON THIS TREND KEEPING THE BORDER DRY
AFTER 00Z.  MID AND UPPER CLOUDS WILL BE LIFTING OFF TO THE NE AS
WELL SO SHOULD SEE DECREASING CLOUDS THROUGH THE NIGHT OVER THE
NORTH.  THE PRESSURE GRADIENT WILL BE TIGHTENING TONIGHT...WHICH
WILL KEEP LOWS WARMER THAN LAST NIGHT.  WILL GO WITH MID TO UPPER
40S FOR LOWS.

WEDNESDAY...UPSTREAM COLD FRONT WILL MOVE INTO THE NORTHERN
MISSISSIPPI VALLEY DURING THE AFTERNOON.  WITH THE AREA FIRMLY IN
THE WARM SECTOR...WILL HAVE MID AND UPPER CLOUDS NORTH AND WEST OF
THE REGION...BUT SHOULD SEE MOSTLY CLEAR TO PARTLY CLOUDY SKIES FOR
THE DAY.  THE PRESSURE GRADIENT WILL TIGHTEN AHEAD OF THE FRONT...AND
SOUTH WINDS WILL TURN GUSTY WITH DAYTIME HEATING AND MIXING.  SOME
GUSTS COULD REACH 30 OR MAYBE EVEN 35 MPH.  HIGHS TOMORROW IN THE
MID 70S TO LOW 80S.

.LONG TERM...WEDNESDAY NIGHT THROUGH NEXT TUESDAY.
ONE OF THE FORECAST CHALLENGES FOR THIS PERIOD IS TRYING TO LASSO
IN THE LOCATIONS OF THE FRONT FOR THE MEMORIAL DAY WEEKEND.
ANOTHER ISSUE IS TIMING AND STRENGTH OF A SHORT WAVE TROUGH FOR
LATER THURSDAY AND ESPECIALLY THURSDAY NIGHT.

LITTLE CHANGE FROM THE GOING FORECAST FROM 24 HOURS AGO FROM
WEDNESDAY NIGHT INTO THURSDAY AS A SURFACE HIGH PRESSURE WITH UPPER
RIDGE DRIFTING OVER THE AREA WILL CONTINUE TO PROVIDE QUIET
WEATHER TO THE AREA. MODELS CONTINUE TO CONFINE CONVECTION OVER
THE NORTHERN PLAINS WITH THE BROAD UPPER TROUGH. PWATS GRADUALLY
INCREASE TO 1.75 ALONG THE FRONT OVER THE NORTHERN PLAINS. UNTIL
THIS UPPER RIDGE IS NUDGED FAR ENOUGH EAST...WILL CONTINUE TO
CONFINE ANY SMALL PCPN MENTION AND CLOUDS WEST OF A RHI TO AUW
LINE.

WILL THEN FOCUS ON HIGHER POPS FOR THE THURSDAY AFTERNOON INTO
THURSDAY NIGHT PERIOD AS A SHORT WAVE SLIDES OVER THE STATE. A
SURFACE LOW AND UPPER JET COUPLET PROGGED TO AFFECT THE NORTH
HALF OF THE STATE DURING THIS PERIOD PROVIDES SOME POTENTIAL OF
STRONG TO SEVERE STORMS. PROGS ARE A BIT MORE PROGRESSIVE WITH THE
FRONTAL PASSAGE LATE THURSDAY NIGHT. USING THE H8 FRONT...THE
FRONT IS DRIVEN SOUTH OF THE AREA FRIDAY INTO FRIDAY NIGHT FOR A
DIMINISHED PERIOD OF CONVECTION. PROGS IN GOOD AGREEMENT WITH H8
WARM FRONT LIFTING BACK NORTH AGAIN ON SATURDAY SO INCREASED
CONVECTION INCLUDING THUNDER FROM SOUTH TO NORTH DURING THE DAY.
PROGS CONTINUE TO LIFT THE FRONT NORTH TO GRADUALLY DIMINISH
CONVECTION OVER CENTRAL AND EAST CENTRAL WISCONSIN BUT WILL
CONFINE BEST PCPN CHANCES ACROSS THE NORTH SUNDAY AND PERHAPS INTO
MONDAY CLOSER TO THE WARM FRONT. AREAS TO THE SOUTH LIKELY TO BE
CAPPED IN A VERY WARM HUMID AIR MASS AS UPPER HEIGHTS BUILD.
ANOTHER FRONT IS PROGGED TO SLIDE OVER MONDAY INTO MONDAY NIGHT
FOR ANOTHER SHOT OF CONVECTION. PWATS INCREASE TO 1.70 INCHES
ALONG THE FRONT...HOWEVER AT THIS TIME IT APPEARS THE FRONTS ARE
A LITTLE TOO PROGRESSIVE FOR HEAVY RAINS TO CONCENTRATE IN ANY ONE
LOCATION WITH THE EXCEPTION OF THE FAR NORTH NEAR THE WARM FRONT.
&&

.AVIATION...HIGH PRESSURE WILL MOVE TO THE EASTERN GREAT LAKES WHILE
A COLD FRONT SHIFTS INTO THE NORTHERN MISSISSIPPI VALLEY BY LATE IN
THE TAF PERIOD.  MID AND HIGH CLOUDS WILL PASS OVER NORTHERN
WISCONSIN THIS AFTERNOON...BUT AM NOT EXPECTING ANY PRECIP.  VFR
CONDITIONS THROUGH THE REST OF THE TAF PERIOD...BUT WILL HAVE WIND
SHEAR DEVELOP OVER N-C WISCONSIN TONIGHT...AND SOUTH WINDS WILL TURN
GUSTY BY LATE MORNING TOMORROW.

MPC
&&

.MARINE...A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED LATE
WEDNESDAY AFTERNOON INTO THURSDAY NIGHT. INCREASING SOUTH WINDS ARE
EXPECTED ON WEDNESDAY...THEN STRONG SOUTH WINDS ARE EXPECTED ON THURSDAY. A
FEW GUSTS COULD APPROACH GALE FORCE NEAR THE SHORELINE THURSDAY
AFTERNOON. WINDS AND WAVES WILL GRADUALLY SUBSIDE THURSDAY NIGHT.

FOR THE UPCOMING MEMORIAL DAY WEEKEND...IT WILL BE UNSETTLED AS
THERE WILL BE CHANCES FOR THUNDERSTORMS EACH DAY. A WARM FRONT
IS EXPECTED TO SLOWLY PUSH NORTHWARD INTO THE AREA OVER THE WEEKEND.
THERE IS A LOT OF UNCERTAINTY ON HOW FAR NORTH THE WARM FRONT WILL
MAKE IT INTO NORTHEAST WISCONSIN AND WHERE THE BEST CHANCES FOR
THUNDERSTORMS WOULD OCCUR.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$
MPC/TDH