Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 08/26/12

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 542 PM CDT FRI AUG 24 2012

.DISCUSSION...
324 PM CDT

TODAY THROUGH SATURDAY NIGHT...
AN UPPER LEVEL DISTURBANCE IS SLOWLY PASSING THROUGH NORTHERN
WISCONSIN AND WILL CONTINUE EASTWARD THROUGH THE NORTHERN GREAT
LAKES THIS EVENING.  SOME OF THE SHORT TERM MODELS INDICATE
SCATTERED SHOWERS WILL DEVELOP ACROSS NORTHERN ILLINOIS...BUT WILL
CONTINUE WITH A DRY FORECAST THIS AFTERNOON.  LATEST RAP ANALYSIS
INDICATES AMPLE CAPE AND LOW LEVEL LAPSE RATES NEAR DRY
ADIABATIC...HOWEVER SUSPECTING THE RAP ANALYSIS MAY BE OVER
ESTIMATING CAPE VALUES. ALSO TOOK INTO CONSIDERATION THAT THE UPPER
LEVEL WAVE IS WELL NORTH OF THE CWA...AND CONVECTION/SHOWERS OVER
LAKE MICHIGAN ARE ASSOCIATED WITH AN AREA OF 850 HPA WARM AIR
ADVECTION.  SCT CU IS BEGINNING TO DEVELOP ROUGHLY ALONG THE I-55
CORRIDOR.

SKIES CLEAR TONIGHT AND EXPECTING A COMFORTABLE NIGHT DESPITE LOW
90S BEING REPORTED ACROSS THE CWA THIS AFTERNOON.  OVERNIGHT LOWS
WILL BE IN THE MID 60S...EXCEPT FOR LOW 70S DOWNTOWN.  SATURDAY WILL
BE MUCH LIKE TODAY...WITH A DRY AND HOT FORECAST.  RAISED INHERITED
TEMPS SUCH THAT TOMORROWS HIGHS ARE A DEGREE OR TWO WARMER THAN
TODAY.  COULD EVEN SEE AREAS IN THE SOUTHERN PORTIONS OF THE CWA
BEING A BIT WARMER THAN CURRENTLY FORECAST.  MODEL SOUNDINGS
INDICATES THERE WILL BE PLENTY OF MIXING TOMORROW...THEREFORE WENT
WITH DEW POINTS SLIGHTLY LOWER THAN PREVIOUSLY FORECAST.  MIN RH
VALUES WILL BE IN THE MID TO UPPER 20 PERCENT RANGE...BUT WITH LIGHT
WINDS FORECAST NOT ANTICIPATING ANY FIRE WEATHER HEADLINES. THAT
BEING SAID A FEW LOCATIONS MAY REACH RED FLAG CRITERIA...AS RFD DID
TODAY.  KEPT PREVIOUS MIN TEMPS FOR SATURDAY NIGHT WITH MID TO UPPER
60S IN THE OUTLYING AREAS...AND IN THE LOW 70S DOWNTOWN.

SUNDAY THROUGH MONDAY NIGHT...
LOW PRESSURE CURRENTLY OVER SOUTHERN SASKATCHEWAN AND THE NORTHERN
GREAT PLAINS WILL MOVE EASTWARD ACROSS SOUTHERN CANADA THROUGH THE
WEEKEND.  THE LOWS COLD FRONT PASSES THROUGH THE CWA LATE SUNDAY
NIGHT INTO MONDAY MORNING.  PRECIP AHEAD OF THE COLD FRONT WAS THE
MAIN FORECAST CHALLENGE TODAY. THE NAM AND GFS LOOKED A BIT FAST
WHILE THE ECMWF HAS BEEN SLOWING THE PROGRESSION OF THE SHOWERS
AND THUNDERSTORMS THE PAST FEW RUNS. WENT WITH A NAM/ECMWF MIX
THAT WAS VERY SIMILAR TO THE PREVIOUS FORECASTS TIMING...WITH
PRECIP REACHING THE WESTERN EDGE OF THE CWA LATE SATURDAY NIGHT.
THAT BEING SAID...THE MODELS ARE INDICATING THE INITIAL UPPER
LEVEL VORTICITY STREAMER ASSOCIATED WITH FIRST WAVE OF PRECIP WILL
BE STRETCHED NORTH TO SOUTH AND FRACTURE SOMEWHERE OVER WISCONSIN.
THE SOUTHERN PART OF THE VORT STREAMER WILL THEN PROGRESS EASTWARD
BRINGING MUCH NEEDED RAIN TO NORTHERN ILLINOIS. CONFIDENCE IS
MEDIUM WITH THE TIMING AND PROGRESSION OF THE PRECIP...BUT HIGH
REGARDING THE POSSIBILITY OF IT BEING A SIGNIFICANT RAINFALL.

PW VALUES WILL BE AROUND TO SLIGHTLY ABOVE 2 INCHES AHEAD OF THE
FRONT...WHICH IS AROUND 2 STANDARD DEVIATIONS ABOVE NORMAL FOR
AUGUST.  THEREFORE SUBSTANTIAL RAINFALL IS POSSIBLE AND AS MENTIONED
IN THE PREVIOUS DISCUSSION...TRAINING CELLS COULD CAUSE ISOLATED
WATER PROBLEMS.

TEMPS ON SUNDAY WILL BE MUCH COOLER WITH AREAS WEST OF I-55 IN THE
UPPER 70S...AND LOW TO MID 80S EXPECTED EAST OF I-55.  TEMPS REBOUND
SLIGHTLY ON MONDAY WITH HIGHS IN THE LOW TO MID 80S.

EXTENDED...TUESDAY THROUGH FRIDAY...
HIGH PRESSURE MOVES IN BEHIND THE COLD FRONT LEADING TO ANOTHER
EXTENDED PERIOD OF DRY WEATHER.  TEMPS INCREASE THROUGHOUT THE
EXTENDED...AND COULD BE EVEN WARMER THAN FORECAST.  EXPECTING UPPER
80S TO QUITE POSSIBLY 90S BY LATE NEXT WEEK.

JEE

&&

.FIRE WEATHER...
428 PM CDT

RH VALUES DROPPED INTO THE 20 PERCENT RANGE ACROSS PARTS OF THE
AREA TODAY...AND SIMILAR CONDITIONS ARE EXPECTED TOMORROW.
TEMPERATURES TOMORROW WILL ONCE AGAIN BE IN THE LOW TO MID
90S...WITH LOWER DEW POINTS THAN TODAY. AMPLE MIXING WILL LIKELY
LEAD TO DEW POINTS DROPPING INTO THE LOW 50S SATURDAY AFTERNOON.
MIN RH VALUES WILL BE IN THE LOW TO MID 20 PERCENT RANGE...HOWEVER
WIND SPEEDS WILL BE AROUND 10 MPH. WIND GUSTS WILL DEVELOP IN THE
AFTERNOON WITH GUSTS UP TO 20 MPH EXPECTED WEST OF I-39...AND
GUSTS AROUND 15 MPH EXPECTED EAST OF I-39. FUEL MOISTURE LEVELS
ARE ABOVE 10 PERCENT FOR MUCH OF NORTHERN ILLINOIS...WHILE AREAS
EAST OF I-55 HAVE 10-HOUR FUELS LESS THAN 10 PERCENT. THEREFORE
TWO OF THE THREE RED FLAG CONDITIONS MAY BE MET IN ISOLATED
LOCATIONS...SIMILAR TO TODAY...BUT NOT EXPECTING ALL THREE RED
FLAG CONDITIONS TO BE MET. THEREFORE NO FIRE WEATHER HEADLINES ARE
ANTICIPATED.

A COLD FRONT MOVES THROUGH THE REGION LATE SATURDAY NIGHT INTO
SUNDAY BRINGING A WIDESPREAD SOAKING RAIN AND COOLER TEMPERATURES
WITH IT.

JEE

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 22Z...

* SS-SSE WINDS AROUND 10 KT OCCASIONALLY GUSTING TO AROUND 15 KT
  THROUGH DUSK.

* SLIGHT POTENTIAL LAKE BREEZE REACHING MDW AND/OR ORD BEFORE
  SUNDOWN.

* VERY LOW PROB ISOLATED SHRA/TSRA OVER NE IL AND EXTREME SE WI
  INTO THIS EVENING.

TRS

//DISCUSSION...UPDATED 22Z...

LAKE BREEZE ONLY MAKING VERY SLOW PROGRESS INLAND. 09-14 KT
SE-ESE WINDS RIGHT ALONG THE SHORE BUT FURTHER INLAND BEHIND
THE BOUNDARY THERE ARE SSE-SE 05-07KT. EXTRAPOLATION USING
RECENT MOVEMENT HAS ARRIVAL AT ORD NOT TIL 02Z. WINDS LATE
AFTERNOON INTO TONIGHT EXPECTED TO REMAIN OUT OF THE S-SSE.

FAIRLY WEAK CONVERGENCE ALONG LAKE BREEZE AND OTHER BOUNDARIES
BUT HAS BEEN ENOUGH TO GENERATE ISOLATED SHRA WITH ADDITIONAL
LIFT PROVIDED BY THE SHORT WAVE TROUGH CURRENTLY MOVING E ALONG
THE WESTERN IL-WI BORDER. EXPECT A FEW MORE ISOLATED SHOWERS
INTO EARLY EVENING THEN DISSIPATION OF THE HIGH BASED CU WITH
LOSS OF SURFACE HEATING WITH SUNSET.

TRS

PREVIOUS DISCUSSION...UPDATED 18Z...

SOUTH-SOUTHWEST WINDS ARE IN PLACE ACROSS THE TERMINALS TODAY...
THANKS TO BROAD SURFACE LOW PRESSURE TROUGH EXTENDING FROM CENTRAL
CANADA TO THE HIGH PLAINS. WHILE GUIDANCE INDICATES SFC WIND
DIRECTION MORE IN THE 170-190 DEG RANGE...OBSERVATIONS HAVE
VARIED MORE IN THE 180-240 DEG RANGE. AMDAR AIRCRAFT SOUNDINGS...
88D VAD WIND PROFILE AND THE WOLCOTT INDIANA WIND PROFILER DEPICT
SWLY WINDS ABOVE THE SURFACE WHICH WOULD SUGGEST MORE OF A SW OR
SSW DIRECTION WILL BE MAINTAINED WITH DEEP MIXING THIS AFTERNOON.
SPEEDS GENERALLY 15 KTS OR LESS THROUGH THE MIXED LAYER...SO
SPEEDS NOT THAT IMPRESSIVE AND GENERALLY AROUND 10 KTS WITH ANY
GUSTS EXPECTED TO BE 15 KTS OR LESS. WEAK LAKE BREEZE NOTED ALONG
THE IL LAKE MICHIGAN SHORE IS NOT ANTICIPATED TO PUSH INLAND
THROUGH ORD/MDW THIS AFTERNOON...THOUGH RECENT RAP/HRRR RUNS DO
INDICATE THIS. OVERALL WEAK LAKE BREEZE PUSH EXPECTED AND SOUTH-
SOUTHWEST GRADIENT DOES NOT INDICATE A STRONG THREAT FOR MAKING IT
INTO THE TERMINALS.

ONLY REAL MINOR CONCERN IS WITH THE OUTSIDE LOW PROBABILITY CHANCE
OF ISOLATED SHRA/TSRA DEVELOPMENT OVER SOUTHEAST WI/NORTHERN IL
THIS AFTERNOON. MID-LEVEL DISTURBANCE IS NOTED IN SATELLITE VAPOR
IMAGERY MOVING EAST ACROSS THE REGION...WITH RELATIVELY STEEP MID-
LEVEL LAPSE RATES DEPICTED IN REGIONAL 12Z SOUNDINGS. ELEVATED
ALTO-CU OVER NORTHERN IL EARLIER TODAY HAS DISSIPATED...THOUGH
MODEL FORECAST SOUNDINGS DEEPEN SURFACE BASED MIXED LAYER TO
AROUND 700 MB THIS AFTERNOON WHICH DOES RESULT IN SOME SHALLOW
MID-LEVEL INSTABILITY. HIGH-RES CONVECTION ALLOWING MODEL RUNS
INCLUDING THE HRRR/RAP AND LOCALLY RUN WRF DO INDICATE SOME
SPOTTY/ISOLATED SHRA/TSRA DEVELOPMENT OVER THE AREA DURING THE
MID/LATE AFTERNOON HOURS. SHALLOW NATURE OF MID-LEVEL INSTABILITY
AND RELATIVELY DRY LOW LEVEL AIR RESULTING IN HIGH LCL/LFC HEIGHTS
IN THE 9-10 KFT RANGE ARGUE AGAINST SIGNIFICANT PROBABILITY OR
COVERAGE HOWEVER...WITH ANY MEAGER POTENTIAL FOR CONVECTION MUCH
TOO LOW TO INCLUDE IN TAF.

SOUTH-SOUTHWEST WINDS BECOMING A LITTLE GUSTIER ARE EXPECTED
SATURDAY WITH A CONTINUATION OF VFR CONDITIONS.

RATZER

//ORD AND MDW CONFIDENCE...UPDATED 22Z...

* HIGH CONFIDENCE ALL ELEMENTS...INCLUDING NO MORE THAN ISOLATED
  SHRA WITH NEAR ZERO CHANCE OF OCCURRENCE AT OR IN IMMEDIATE
  VICINITY OF TERMINALS.

TRS

//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...

SATURDAY NIGHT...VFR.

SUNDAY...TSRA LIKELY IN THE AFTERNOON AND EVE. DEVELOPING MVFR
LIKELY. IFR POSSIBLE BY NIGHT.

MONDAY...SLIGHT CHANCE OF MORNING TSRA.

TUESDAY-THURSDAY...VFR.

MTF

&&

.MARINE...
219 PM CDT

PATTERN REMAINS LARGELY UNCHANGED TODAY AND WILL CONTINUE TO PERSIST
THROUGH MUCH OF THE WEEKEND AS HIGH PRESSURE REMAINS ANCHORED OVER
THE EASTERN STATES AND LOW PRESSURE PERSISTS OVER THE CANADIAN
PRAIRIES. SOUTHERLY FLOW WILL CONTINUE ACROSS LAKE MICHIGAN UNTIL
LATE SUNDAY. THROUGH SUNDAY NIGHT...THE LOW PRESSURE IS FORECAST TO
DEEPEN AS IT LIFTS NORTHEAST TOWARDS HUDSON BAY...AND A TRAILING
COLD FRONT IS EXPECTED TO MOVE ACROSS LAKE MICHIGAN LATE SUNDAY
NIGHT INTO MONDAY TURNING WINDS TO THE WEST OR NORTHWEST. HIGH
PRESSURE WILL THEN BUILD ACROSS THE PLAINS STATES AND MOVE
EAST...BECOMING CENTERED JUST SOUTH OF THE GREAT LAKES REGION. THE
WINDS WILL BE LIGHT OVER THE SOUTHERN HALF OF THE LAKE CLOSE TO THE
HIGH CENTER...BUT THE NORTH HALF OF THE LAKE WILL SEE SLIGHTLY
WINDIER CONDITIONS AS ANOTHER AREA OF LOW PRESSURE DEVELOPS ACROSS
THE CANADIAN PRAIRIES AND A MODEST PRESSURE GRADIENT DEVELOPS OVER
NORTHERN LAKE MICHIGAN. BMD

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

$$







AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 444 PM CDT FRI AUG 24 2012

.DISCUSSION...
324 PM CDT

TODAY THROUGH SATURDAY NIGHT...
AN UPPER LEVEL DISTURBANCE IS SLOWLY PASSING THROUGH NORTHERN
WISCONSIN AND WILL CONTINUE EASTWARD THROUGH THE NORTHERN GREAT
LAKES THIS EVENING.  SOME OF THE SHORT TERM MODELS INDICATE
SCATTERED SHOWERS WILL DEVELOP ACROSS NORTHERN ILLINOIS...BUT WILL
CONTINUE WITH A DRY FORECAST THIS AFTERNOON.  LATEST RAP ANALYSIS
INDICATES AMPLE CAPE AND LOW LEVEL LAPSE RATES NEAR DRY
ADIABATIC...HOWEVER SUSPECTING THE RAP ANALYSIS MAY BE OVER
ESTIMATING CAPE VALUES. ALSO TOOK INTO CONSIDERATION THAT THE UPPER
LEVEL WAVE IS WELL NORTH OF THE CWA...AND CONVECTION/SHOWERS OVER
LAKE MICHIGAN ARE ASSOCIATED WITH AN AREA OF 850 HPA WARM AIR
ADVECTION.  SCT CU IS BEGINNING TO DEVELOP ROUGHLY ALONG THE I-55
CORRIDOR.

SKIES CLEAR TONIGHT AND EXPECTING A COMFORTABLE NIGHT DESPITE LOW
90S BEING REPORTED ACROSS THE CWA THIS AFTERNOON.  OVERNIGHT LOWS
WILL BE IN THE MID 60S...EXCEPT FOR LOW 70S DOWNTOWN.  SATURDAY WILL
BE MUCH LIKE TODAY...WITH A DRY AND HOT FORECAST.  RAISED INHERITED
TEMPS SUCH THAT TOMORROWS HIGHS ARE A DEGREE OR TWO WARMER THAN
TODAY.  COULD EVEN SEE AREAS IN THE SOUTHERN PORTIONS OF THE CWA
BEING A BIT WARMER THAN CURRENTLY FORECAST.  MODEL SOUNDINGS
INDICATES THERE WILL BE PLENTY OF MIXING TOMORROW...THEREFORE WENT
WITH DEWPOINTS SLIGHTLY LOWER THAN PREVIOUSLY FORECAST.  MIN RH
VALUES WILL BE IN THE MID TO UPPER 20 PERCENT RANGE...BUT WITH LIGHT
WINDS FORECAST NOT ANTICIPATING ANY FIRE WEATHER HEADLINES. THAT
BEING SAID A FEW LOCATIONS MAY REACH RED FLAG CRITERIA...AS RFD DID
TODAY.  KEPT PREVIOUS MIN TEMPS FOR SATURDAY NIGHT WITH MID TO UPPER
60S IN THE OUTLYING AREAS...AND IN THE LOW 70S DOWNTOWN.

SUNDAY THROUGH MONDAY NIGHT...
LOW PRESSURE CURRENTLY OVER SOUTHERN SASKATCHEWAN AND THE NORTHERN
GREAT PLAINS WILL MOVE EASTWARD ACROSS SOUTHERN CANADA THROUGH THE
WEEKEND.  THE LOWS COLD FRONT PASSES THROUGH THE CWA LATE SUNDAY
NIGHT INTO MONDAY MORNING.  PRECIP AHEAD OF THE COLD FRONT WAS THE
MAIN FORECAST CHALLENGE TODAY. THE NAM AND GFS LOOKED A BIT FAST
WHILE THE ECMWF HAS BEEN SLOWING THE PROGRESSION OF THE SHOWERS
AND THUNDERSTORMS THE PAST FEW RUNS. WENT WITH A NAM/ECMWF MIX
THAT WAS VERY SIMILAR TO THE PREVIOUS FORECASTS TIMING...WITH
PRECIP REACHING THE WESTERN EDGE OF THE CWA LATE SATURDAY NIGHT.
THAT BEING SAID...THE MODELS ARE INDICATING THE INITIAL UPPER
LEVEL VORTICITY STREAMER ASSOCIATED WITH FIRST WAVE OF PRECIP WILL
BE STRETCHED NORTH TO SOUTH AND FRACTURE SOMEWHERE OVER WISCONSIN.
THE SOUTHERN PART OF THE VORT STREAMER WILL THEN PROGRESS EASTWARD
BRINGING MUCH NEEDED RAIN TO NORTHERN ILLINOIS. CONFIDENCE IS
MEDIUM WITH THE TIMING AND PROGRESSION OF THE PRECIP...BUT HIGH
REGARDING THE POSSIBILITY OF IT BEING A SIGNIFICANT RAINFALL.

PW VALUES WILL BE AROUND TO SLIGHTLY ABOVE 2 INCHES AHEAD OF THE
FRONT...WHICH IS AROUND 2 STANDARD DEVIATIONS ABOVE NORMAL FOR
AUGUST.  THEREFORE SUBSTANTIAL RAINFALL IS POSSIBLE AND AS MENTIONED
IN THE PREVIOUS DISCUSSION...TRAINING CELLS COULD CAUSE ISOLATED
WATER PROBLEMS.

TEMPS ON SUNDAY WILL BE MUCH COOLER WITH AREAS WEST OF I-55 IN THE
UPPER 70S...AND LOW TO MID 80S EXPECTED EAST OF I-55.  TEMPS REBOUND
SLIGHTLY ON MONDAY WITH HIGHS IN THE LOW TO MID 80S.

EXTENDED...TUESDAY THROUGH FRIDAY...
HIGH PRESSURE MOVES IN BEHIND THE COLD FRONT LEADING TO ANOTHER
EXTENDED PERIOD OF DRY WEATHER.  TEMPS INCREASE THROUGHOUT THE
EXTENDED...AND COULD BE EVEN WARMER THAN FORECAST.  EXPECTING UPPER
80S TO QUITE POSSIBLY 90S BY LATE NEXT WEEK.

JEE

&&

.FIRE WEATHER...
428 PM CDT

RH VALUES DROPPED INTO THE 20 PERCENT RANGE ACROSS PARTS OF THE
AREA TODAY...AND SIMILAR CONDITIONS ARE EXPECTED TOMORROW.
TEMPERATURES TOMORROW WILL ONCE AGAIN BE IN THE LOW TO MID
90S...WITH LOWER DEWPOINTS THAN TODAY. AMPLE MIXING WILL LIKELY
LEAD TO DEWPOINTS DROPPING INTO THE LOW 50S SATURDAY AFTERNOON.
MIN RH VALUES WILL BE IN THE LOW TO MID 20 PERCENT RANGE...HOWEVER
WIND SPEEDS WILL BE AROUND 10 MPH. WIND GUSTS WILL DEVELOP IN THE
AFTERNOON WITH GUSTS UP TO 20 MPH EXPECTED WEST OF I-39...AND
GUSTS AROUND 15 MPH EXPECTED EAST OF I-39. FUEL MOISTURE LEVELS
ARE ABOVE 10 PERCENT FOR MUCH OF NORTHERN ILLINOIS...WHILE AREAS
EAST OF I-55 HAVE 10-HOUR FUELS LESS THAN 10 PERCENT. THEREFORE
TWO OF THE THREE RED FLAG CONDITIONS MAY BE MET IN ISOLATED
LOCATIONS...SIMILAR TO TODAY...BUT NOT EXPECTING ALL THREE RED
FLAG CONDITIONS TO BE MET. THEREFORE NO FIRE WEATHER HEADLINES ARE
ANTICIPATED.

A COLD FRONT MOVES THROUGH THE REGION LATE SATURDAY NIGHT INTO
SUNDAY BRINGING A WIDESPREAD SOAKING RAIN AND COOLER TEMPERATURES
WITH IT.

JEE

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 20Z...

* SOUTH-SOUTHWEST WINDS 10-15 KTS THIS AFTERNOON BECOMING LIGHT
  SOUTH THIS EVENING.

* LAKE BREEZE EXPECTED TO REMAIN EAST OF ORD/MDW.

* VERY LOW PROBABILITY OF ISOLATED SHRA/TSRA DEVELOPMENT OVER
  NORTHEAST IL THIS AFTERNOON.

RATZER

//DISCUSSION...UPDATED 18Z...

SOUTH-SOUTHWEST WINDS ARE IN PLACE ACROSS THE TERMINALS TODAY...
THANKS TO BROAD SURFACE LOW PRESSURE TROUGH EXTENDING FROM CENTRAL
CANADA TO THE HIGH PLAINS. WHILE GUIDANCE INDICATES SFC WIND
DIRECTION MORE IN THE 170-190 DEG RANGE...OBSERVATIONS HAVE
VARIED MORE IN THE 180-240 DEG RANGE. AMDAR AIRCRAFT SOUNDINGS...
88D VAD WIND PROFILE AND THE WOLCOTT INDIANA WIND PROFILER DEPICT
SWLY WINDS ABOVE THE SURFACE WHICH WOULD SUGGEST MORE OF A SW OR
SSW DIRECTION WILL BE MAINTAINED WITH DEEP MIXING THIS AFTERNOON.
SPEEDS GENERALLY 15 KTS OR LESS THROUGH THE MIXED LAYER...SO
SPEEDS NOT THAT IMPRESSIVE AND GENERALLY AROUND 10 KTS WITH ANY
GUSTS EXPECTED TO BE 15 KTS OR LESS. WEAK LAKE BREEZE NOTED ALONG
THE IL LAKE MICHIGAN SHORE IS NOT ANTICIPATED TO PUSH INLAND
THROUGH ORD/MDW THIS AFTERNOON...THOUGH RECENT RAP/HRRR RUNS DO
INDICATE THIS. OVERALL WEAK LAKE BREEZE PUSH EXPECTED AND SOUTH-
SOUTHWEST GRADIENT DOES NOT INDICATE A STRONG THREAT FOR MAKING IT
INTO THE TERMINALS.

ONLY REAL MINOR CONCERN IS WITH THE OUTSIDE LOW PROBABILITY CHANCE
OF ISOLATED SHRA/TSRA DEVELOPMENT OVER SOUTHEAST WI/NORTHERN IL
THIS AFTERNOON. MID-LEVEL DISTURBANCE IS NOTED IN SATELLITE VAPOR
IMAGERY MOVING EAST ACROSS THE REGION...WITH RELATIVELY STEEP MID-
LEVEL LAPSE RATES DEPICTED IN REGIONAL 12Z SOUNDINGS. ELEVATED
ALTO-CU OVER NORTHERN IL EARLIER TODAY HAS DISSIPATED...THOUGH
MODEL FORECAST SOUNDINGS DEEPEN SURFACE BASED MIXED LAYER TO
AROUND 700 MB THIS AFTERNOON WHICH DOES RESULT IN SOME SHALLOW
MID-LEVEL INSTABILITY. HIGH-RES CONVECTION ALLOWING MODEL RUNS
INCLUDING THE HRRR/RAP AND LOCALLY RUN WRF DO INDICATE SOME
SPOTTY/ISOLATED SHRA/TSRA DEVELOPMENT OVER THE AREA DURING THE
MID/LATE AFTERNOON HOURS. SHALLOW NATURE OF MID-LEVEL INSTABILITY
AND RELATIVELY DRY LOW LEVEL AIR RESULTING IN HIGH LCL/LFC HEIGHTS
IN THE 9-10 KFT RANGE ARGUE AGAINST SIGNIFICANT PROBABILITY OR
COVERAGE HOWEVER...WITH ANY MEAGER POTENTIAL FOR CONVECTION MUCH
TOO LOW TO INCLUDE IN TAF.

SOUTH-SOUTHWEST WINDS BECOMING A LITTLE GUSTIER ARE EXPECTED
SATURDAY WITH A CONTINUATION OF VFR CONDITIONS.

RATZER

//ORD AND MDW CONFIDENCE...UPDATED 20Z...

* HIGH CONFIDENCE IN ALL ELEMENTS.

* HIGH CONFIDENCE IN ANY SHRA/TSRA BEING LOW COVERAGE IF THEY WERE
  TO DEVELOP.

RATZER

//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...

SATURDAY NIGHT...VFR.

SUNDAY...TSRA LIKELY IN THE AFTERNOON AND EVE. DEVELOPING MVFR
LIKELY. IFR POSSIBLE BY NIGHT.

MONDAY...SLIGHT CHANCE OF MORNING TSRA.

TUESDAY-THURSDAY...VFR.

MTF

&&

.MARINE...
219 PM CDT

PATTERN REMAINS LARGELY UNCHANGED TODAY AND WILL CONTINUE TO PERSIST
THROUGH MUCH OF THE WEEKEND AS HIGH PRESSURE REMAINS ANCHORED OVER
THE EASTERN STATES AND LOW PRESSURE PERSISTS OVER THE CANADIAN
PRAIRIES. SOUTHERLY FLOW WILL CONTINUE ACROSS LAKE MICHIGAN UNTIL
LATE SUNDAY. THROUGH SUNDAY NIGHT...THE LOW PRESSURE IS FORECAST TO
DEEPEN AS IT LIFTS NORTHEAST TOWARDS HUDSON BAY...AND A TRAILING
COLD FRONT IS EXPECTED TO MOVE ACROSS LAKE MICHIGAN LATE SUNDAY
NIGHT INTO MONDAY TURNING WINDS TO THE WEST OR NORTHWEST. HIGH
PRESSURE WILL THEN BUILD ACROSS THE PLAINS STATES AND MOVE
EAST...BECOMING CENTERED JUST SOUTH OF THE GREAT LAKES REGION. THE
WINDS WILL BE LIGHT OVER THE SOUTHERN HALF OF THE LAKE CLOSE TO THE
HIGH CENTER...BUT THE NORTH HALF OF THE LAKE WILL SEE SLIGHTLY
WINDIER CONDITIONS AS ANOTHER AREA OF LOW PRESSURE DEVELOPS ACROSS
THE CANADIAN PRAIRIES AND A MODEST PRESSURE GRADIENT DEVELOPS OVER
NORTHERN LAKE MICHIGAN. BMD

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

$$








AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 327 PM CDT FRI AUG 24 2012

.DISCUSSION...
324 PM CDT

TODAY THROUGH SATURDAY NIGHT...
AN UPPER LEVEL DISTURBANCE IS SLOWLY PASSING THROUGH NORTHERN
WISCONSIN AND WILL CONTINUE EASTWARD THROUGH THE NORTHERN GREAT
LAKES THIS EVENING.  SOME OF THE SHORT TERM MODELS INDICATE
SCATTERED SHOWERS WILL DEVELOP ACROSS NORTHERN ILLINOIS...BUT WILL
CONTINUE WITH A DRY FORECAST THIS AFTERNOON.  LATEST RAP ANALYSIS
INDICATES AMPLE CAPE AND LOW LEVEL LAPSE RATES NEAR DRY
ADIABATIC...HOWEVER SUSPECTING THE RAP ANALYSIS MAY BE OVER
ESTIMATING CAPE VALUES. ALSO TOOK INTO CONSIDERATION THAT THE UPPER
LEVEL WAVE IS WELL NORTH OF THE CWA...AND CONVECTION/SHOWERS OVER
LAKE MICHIGAN ARE ASSOCIATED WITH AN AREA OF 850 HPA WARM AIR
ADVECTION.  SCT CU IS BEGINNING TO DEVELOP ROUGHLY ALONG THE I-55
CORRIDOR.

SKIES CLEAR TONIGHT AND EXPECTING A COMFORTABLE NIGHT DESPITE LOW
90S BEING REPORTED ACROSS THE CWA THIS AFTERNOON.  OVERNIGHT LOWS
WILL BE IN THE MID 60S...EXCEPT FOR LOW 70S DOWNTOWN.  SATURDAY WILL
BE MUCH LIKE TODAY...WITH A DRY AND HOT FORECAST.  RAISED INHERITED
TEMPS SUCH THAT TOMORROWS HIGHS ARE A DEGREE OR TWO WARMER THAN
TODAY.  COULD EVEN SEE AREAS IN THE SOUTHERN PORTIONS OF THE CWA
BEING A BIT WARMER THAN CURRENTLY FORECAST.  MODEL SOUNDINGS
INDICATES THERE WILL BE PLENTY OF MIXING TOMORROW...THEREFORE WENT
WITH DEWPOINTS SLIGHTLY LOWER THAN PREVIOUSLY FORECAST.  MIN RH
VALUES WILL BE IN THE MID TO UPPER 20 PERCENT RANGE...BUT WITH LIGHT
WINDS FORECAST NOT ANTICIPATING ANY FIRE WEATHER HEADLINES. THAT
BEING SAID A FEW LOCATIONS MAY REACH RED FLAG CRITERIA...AS RFD DID
TODAY.  KEPT PREVIOUS MIN TEMPS FOR SATURDAY NIGHT WITH MID TO UPPER
60S IN THE OUTLYING AREAS...AND IN THE LOW 70S DOWNTOWN.

SUNDAY THROUGH MONDAY NIGHT...
LOW PRESSURE CURRENTLY OVER SOUTHERN SASKATCHEWAN AND THE NORTHERN
GREAT PLAINS WILL MOVE EASTWARD ACROSS SOUTHERN CANADA THROUGH THE
WEEKEND.  THE LOWS COLD FRONT PASSES THROUGH THE CWA LATE SUNDAY
NIGHT INTO MONDAY MORNING.  PRECIP AHEAD OF THE COLD FRONT WAS THE
MAIN FORECAST CHALLENGE TODAY. THE NAM AND GFS LOOKED A BIT FAST
WHILE THE ECMWF HAS BEEN SLOWING THE PROGRESSION OF THE SHOWERS
AND THUNDERSTORMS THE PAST FEW RUNS. WENT WITH A NAM/ECMWF MIX
THAT WAS VERY SIMILAR TO THE PREVIOUS FORECASTS TIMING...WITH
PRECIP REACHING THE WESTERN EDGE OF THE CWA LATE SATURDAY NIGHT.
THAT BEING SAID...THE MODELS ARE INDICATING THE INITIAL UPPER
LEVEL VORTICITY STREAMER ASSOCIATED WITH FIRST WAVE OF PRECIP WILL
BE STRETCHED NORTH TO SOUTH AND FRACTURE SOMEWHERE OVER WISCONSIN.
THE SOUTHERN PART OF THE VORT STREAMER WILL THEN PROGRESS EASTWARD
BRINGING MUCH NEEDED RAIN TO NORTHERN ILLINOIS. CONFIDENCE IS
MEDIUM WITH THE TIMING AND PROGRESSION OF THE PRECIP...BUT HIGH
REGARDING THE POSSIBILITY OF IT BEING A SIGNIFICANT RAINFALL.

PW VALUES WILL BE AROUND TO SLIGHTLY ABOVE 2 INCHES AHEAD OF THE
FRONT...WHICH IS AROUND 2 STANDARD DEVIATIONS ABOVE NORMAL FOR
AUGUST.  THEREFORE SUBSTANTIAL RAINFALL IS POSSIBLE AND AS MENTIONED
IN THE PREVIOUS DISCUSSION...TRAINING CELLS COULD CAUSE ISOLATED
WATER PROBLEMS.

TEMPS ON SUNDAY WILL BE MUCH COOLER WITH AREAS WEST OF I-55 IN THE
UPPER 70S...AND LOW TO MID 80S EXPECTED EAST OF I-55.  TEMPS REBOUND
SLIGHTLY ON MONDAY WITH HIGHS IN THE LOW TO MID 80S.

EXTENDED...TUESDAY THROUGH FRIDAY...
HIGH PRESSURE MOVES IN BEHIND THE COLD FRONT LEADING TO ANOTHER
EXTENDED PERIOD OF DRY WEATHER.  TEMPS INCREASE THROUGHOUT THE
EXTENDED...AND COULD BE EVEN WARMER THAN FORECAST.  EXPECTING UPPER
80S TO QUITE POSSIBLY 90S BY LATE NEXT WEEK.

JEE

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 20Z...

* SOUTH-SOUTHWEST WINDS 10-15 KTS THIS AFTERNOON BECOMING LIGHT
  SOUTH THIS EVENING.

* LAKE BREEZE EXPECTED TO REMAIN EAST OF ORD/MDW.

* VERY LOW PROBABILITY OF ISOLATED SHRA/TSRA DEVELOPMENT OVER
  NORTHEAST IL THIS AFTERNOON.

RATZER

//DISCUSSION...UPDATED 18Z...

SOUTH-SOUTHWEST WINDS ARE IN PLACE ACROSS THE TERMINALS TODAY...
THANKS TO BROAD SURFACE LOW PRESSURE TROUGH EXTENDING FROM CENTRAL
CANADA TO THE HIGH PLAINS. WHILE GUIDANCE INDICATES SFC WIND
DIRECTION MORE IN THE 170-190 DEG RANGE...OBSERVATIONS HAVE
VARIED MORE IN THE 180-240 DEG RANGE. AMDAR AIRCRAFT SOUNDINGS...
88D VAD WIND PROFILE AND THE WOLCOTT INDIANA WIND PROFILER DEPICT
SWLY WINDS ABOVE THE SURFACE WHICH WOULD SUGGEST MORE OF A SW OR
SSW DIRECTION WILL BE MAINTAINED WITH DEEP MIXING THIS AFTERNOON.
SPEEDS GENERALLY 15 KTS OR LESS THROUGH THE MIXED LAYER...SO
SPEEDS NOT THAT IMPRESSIVE AND GENERALLY AROUND 10 KTS WITH ANY
GUSTS EXPECTED TO BE 15 KTS OR LESS. WEAK LAKE BREEZE NOTED ALONG
THE IL LAKE MICHIGAN SHORE IS NOT ANTICIPATED TO PUSH INLAND
THROUGH ORD/MDW THIS AFTERNOON...THOUGH RECENT RAP/HRRR RUNS DO
INDICATE THIS. OVERALL WEAK LAKE BREEZE PUSH EXPECTED AND SOUTH-
SOUTHWEST GRADIENT DOES NOT INDICATE A STRONG THREAT FOR MAKING IT
INTO THE TERMINALS.

ONLY REAL MINOR CONCERN IS WITH THE OUTSIDE LOW PROBABILITY CHANCE
OF ISOLATED SHRA/TSRA DEVELOPMENT OVER SOUTHEAST WI/NORTHERN IL
THIS AFTERNOON. MID-LEVEL DISTURBANCE IS NOTED IN SATELLITE VAPOR
IMAGERY MOVING EAST ACROSS THE REGION...WITH RELATIVELY STEEP MID-
LEVEL LAPSE RATES DEPICTED IN REGIONAL 12Z SOUNDINGS. ELEVATED
ALTO-CU OVER NORTHERN IL EARLIER TODAY HAS DISSIPATED...THOUGH
MODEL FORECAST SOUNDINGS DEEPEN SURFACE BASED MIXED LAYER TO
AROUND 700 MB THIS AFTERNOON WHICH DOES RESULT IN SOME SHALLOW
MID-LEVEL INSTABILITY. HIGH-RES CONVECTION ALLOWING MODEL RUNS
INCLUDING THE HRRR/RAP AND LOCALLY RUN WRF DO INDICATE SOME
SPOTTY/ISOLATED SHRA/TSRA DEVELOPMENT OVER THE AREA DURING THE
MID/LATE AFTERNOON HOURS. SHALLOW NATURE OF MID-LEVEL INSTABILITY
AND RELATIVELY DRY LOW LEVEL AIR RESULTING IN HIGH LCL/LFC HEIGHTS
IN THE 9-10 KFT RANGE ARGUE AGAINST SIGNIFICANT PROBABILITY OR
COVERAGE HOWEVER...WITH ANY MEAGER POTENTIAL FOR CONVECTION MUCH
TOO LOW TO INCLUDE IN TAF.

SOUTH-SOUTHWEST WINDS BECOMING A LITTLE GUSTIER ARE EXPECTED
SATURDAY WITH A CONTINUATION OF VFR CONDITIONS.

RATZER

//ORD AND MDW CONFIDENCE...UPDATED 20Z...

* HIGH CONFIDENCE IN ALL ELEMENTS.

* HIGH CONFIDENCE IN ANY SHRA/TSRA BEING LOW COVERAGE IF THEY WERE
  TO DEVELOP.

RATZER

//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...

SATURDAY NIGHT...VFR.

SUNDAY...TSRA LIKELY IN THE AFTERNOON AND EVE. DEVELOPING MVFR
LIKELY. IFR POSSIBLE BY NIGHT.

MONDAY...SLIGHT CHANCE OF MORNING TSRA.

TUESDAY-THURSDAY...VFR.

MTF

&&

.MARINE...
219 PM CDT

PATTERN REMAINS LARGELY UNCHANGED TODAY AND WILL CONTINUE TO PERSIST
THROUGH MUCH OF THE WEEKEND AS HIGH PRESSURE REMAINS ANCHORED OVER
THE EASTERN STATES AND LOW PRESSURE PERSISTS OVER THE CANADIAN
PRAIRIES. SOUTHERLY FLOW WILL CONTINUE ACROSS LAKE MICHIGAN UNTIL
LATE SUNDAY. THROUGH SUNDAY NIGHT...THE LOW PRESSURE IS FORECAST TO
DEEPEN AS IT LIFTS NORTHEAST TOWARDS HUDSON BAY...AND A TRAILING
COLD FRONT IS EXPECTED TO MOVE ACROSS LAKE MICHIGAN LATE SUNDAY
NIGHT INTO MONDAY TURNING WINDS TO THE WEST OR NORTHWEST. HIGH
PRESSURE WILL THEN BUILD ACROSS THE PLAINS STATES AND MOVE
EAST...BECOMING CENTERED JUST SOUTH OF THE GREAT LAKES REGION. THE
WINDS WILL BE LIGHT OVER THE SOUTHERN HALF OF THE LAKE CLOSE TO THE
HIGH CENTER...BUT THE NORTH HALF OF THE LAKE WILL SEE SLIGHTLY
WINDIER CONDITIONS AS ANOTHER AREA OF LOW PRESSURE DEVELOPS ACROSS
THE CANADIAN PRAIRIES AND A MODEST PRESSURE GRADIENT DEVELOPS OVER
NORTHERN LAKE MICHIGAN. BMD

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

$$






AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 256 AM CDT FRI AUG 24 2012

.DISCUSSION...

UPDATE...
1043 PM

FOR REST OF TONIGHT...

NO SIGNIFICANT CHANGES MADE TO FORECAST GRIDS AND DERIVED TEXT
PRODUCTS THOUGH DID DO SOME TWEAKING FOR RECENT TRENDS.

DURING THE LATER AFTERNOON TMKE RADAR DETECTED AN INCREASINGLY
DEFINED LINE OF LOW LEVEL CONVERGENCE FROM JUST OFFSHORE OF
HIGHWOOD AND LAKE BLUFF IN SOUTHEAST LAKE CO. IL BOWING OUT OVER
THE LAKE THEN CURVING BACK TO THE SHORELINE NEAR PORT WASHINGTON
IN EAST CENTRAL OZAUKEE CO. WI.

WHILE THE RUC13 HAS SHOWN SURFACE CONVERGENCE ALONG AND JUST
INLAND IN THIS AREA DUE TO A MODEST LAKE BREEZE...THE HRR3
PLACED THIS LINEAR CONVERGENT ZONE...DUE TO SPEED CONVERGENCE PER
THIS MODEL...MUCH BETTER.

SURFACE/LOW LEVEL CONVERGENCE COMBINED WITH WEAK LOW LEVEL WARM
AIR ADVECTION AND VERY MODEST MID LEVEL COOLING AND A VERY MINOR
DISTURBANCE MOVING EAST ACROSS SOUTHERN WI AND NORTHERN IL DURING
THE LATE AFTERNOON THROUGH MID EVENING COMBINED TO ALLOW CAPE
VALES TO GROW AND SHOWERS TO FORM ALONG THIS LINE. WHILE THE
SOUTHERN EXTENT OF THESE SHOWERS HAS BEEN MOVING NORTHWARD AND
WEAKENING DURING THE MID TO LATE EVENING... AT THE SAME TIME
ANOTHER SIMILAR LINE HAS APPEARED BETWEEN THE SAME END POINTS BUT
BOWING ALL THE WAY OUT TO MID LAKE OFF OF RAC AND MKE. A FEW WEAK
SHOWERS WERE ALONG THIS LINE.

PREMISED ON THE HRR CONTINUING TO DEPICT THE LINEAR CONVERGENCE
ZONE...THE AREA OF CONVERGENCE WILL SHIFT SOUTH TO OFF OF THE IL
SHORE BEFORE WEAKENING AS IT DRIFTS OUT TOWARD MID LAKE BY 06Z.
THUS THE THREAT OF SHOWERS WITH THESE FEATURES LOOKS TO BE LOW AT
BEST.

A LONE SHOWER MOVED INTO SOUTHERN LASALLE CO. EARLY THIS EVENING
THEN DISSIPATED AS IT CONTINUE TO THE NORTHEAST. THIS ISOLATED
SHOWER WAS A RESULT OF THE INCREASED LIFT ASSOCIATED WITH THE
MINOR SHORT WAVE MOVING OVER THE NORTHERN END OF AN AREA OF WELL
DEFINED MODERATE CU WITH THE LOSS OF HEATING RESULTING IN ITS
DEMISE.

FOR THE OVERNIGHT...LATEST RUNS OF NAM...RUC AND HRR ALL KEEP THE
LOCAL FORECAST AREA DRY WITH THE RAIN FALLING FROM EASTERN WI
SOUTHWESTWARD ACROSS IA. WITH A STRONGER SHORT WAVE TROUGH MOVING
EAST ACROSS MN AND FAR NORTHERN IA AT LATE EVENING AND PROGGED TO
CONTINUE EAST HAVE RETAINED THE SLIGHT CHANCE POPS ACROSS THE
NORTHERN PORTION OF THE FORECAST AREA...AND WITH THE TROUGH TO
REACH FAR EASTERN WI AND FAR NORTHEAST IL BY EARLY TO MID MORNING
HAVE LEFT THE LOW POPS DURING FRI AS IS.

TRS

//PREV DISCUSSION...
344 PM CDT

MAIN FORECAST CONCERNS/CHALLENGES THIS FORECAST PERIOD ARE WITH
CLOUD TRENDS THIS EVENING AND TONIGHT AS WELL AS FOR A SLIGHT
CHANCE OF LIGHT SHOWERS TONIGHT.

RELATIVELY QUIET BUT WARM CONDITIONS CURRENTLY ACROSS THE
CWA...WITH SOME MID/HIGH LEVEL CLOUD COVER PASSING OVERHEAD. AS
SEVERAL MID LEVEL FEATURES CONTINUE TO SHIFT EAST THIS
EVENING...SOUTHWEST MID LEVEL FLOW WILL ALLOW FOR A CONTINUED
SETUP FOR WAA TO OCCUR. ALTHOUGH THIS WAA/ASCENT WILL BE FAIRLY
WEAK...IT SHOULD BE ENOUGH TO OVERCOME SOME DRIER AIR AND ALLOW
FOR REDEVELOPMENT OF MID LEVEL CLOUDS ACROSS MUCH OF THE REGION.
ALTHOUGH NOT EXACTLY THE SAME SETUP FROM THIS MORNING...A SIMILAR
SITUATION WITH PARTLY CLOUDY/CLOUD SKIES AND SOME LIGHT SHOWERS
COULD ONCE AGAIN OCCUR...ESPECIALLY WITH SOME WEAK MID LEVEL
RIPPLES PASSING OVERHEAD AS WELL AS A LIFTING FRONTAL BOUNDARY. SO
HAVE MADE MENTION OF A SLIGHT CHANCE OF LIGHT SHOWERS TONIGHT.
THUNDER SHOULD BE NONEXISTENT ONCE AGAIN AS BETTER FORCING WILL BE
TIED MORE TOWARD A STRONGER WAVE FURTHER TO THE NORTH ACROSS
WISCONSIN TONIGHT. AS THIS WAVE SHIFTS EAST OF THE REGION FRIDAY
MORNING...ANY PRECIP/CLOUD COVER WILL EXIT AND DIMINISH MAKING WAY
FOR PARTLY CLOUDY SKIES. WITH THERMAL AXIS SHIFTING
OVERHEAD...TEMPS SHOULD RISE FAIRLY EASILY TOMORROW WITH HIGH
TEMPERATURES IN THE LOWER 90S EXPECTED. WITH SOME LOCATIONS IN THE
WESTERN CWA ALREADY OBSERVING LOWER 90S TODAY...IT WOULD NOT BE
OUT OF THE QUESTION FOR SOME MID 90S TO OCCUR AS WELL. DESPITE
THIS WARM UP...LOW HUMIDITY AND SOME SUNSHINE WILL HELP TO PROVIDE
ANOTHER PLEASANT DAY. HAVE ALSO MAINTAINED LOWER 90S INTO SATURDAY
WITH REALLY NO CHANGE IN THE OVERALL SETUP EXPECTED.

THE NEXT BEST CHANCE FOR PRECIP IS STILL APPEARING TO BE LATE IN
THE WEEKEND AS A WAVE EJECTS OUT OF THE CENTRAL PLAINS. THIS
SHOULD INDUCE SOME DECENT PRESSURE FALLS AND HELP THIS SYSTEM WRAP
SOME GOOD MOISTURE INTO IT. WITH GUIDANCE STILL VARYING ON ITS
OVERALL EVOLUTION...HAVE NOT GONE TOO HIGH WITH POPS FOR SUNDAY
BUT DID INCREASE TO HIGH CHANCE POPS FOR MOST OF THE CWA ON SUNDAY
WITH MOST GUIDANCE SPEEDING UP THIS SYSTEM. THIS SYSTEM WILL NEED
TO CONTINUE BE MONITORED...DUE TO THE OVERALL STRENGTH OF THE
CONVECTIVE POTENTIAL STILL UNKNOWN AS WELL AS CHANCES FOR SOME
DECENT RAINFALL.

RODRIGUEZ

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 06Z...

* 30-35 KT SOUTHWESTERLY FLOW AT 1000-1500 FT THROUGH 13Z.
* SMALL CHANCE FOR ISOLATED SHRA THIS AFTERNOON AND EVENING.

//DISCUSSION...UPDATED 06Z...

THE TERMINALS TODAY WILL REMAIN BETWEEN HIGH PRESSURE CENTERED
ACROSS THE NORTHEAST AND A WEAKENING LOW PRESSURE TROUGH MOVING
FROM MN TO THE UPPER GREAT LAKES. WARM AIR ADVECTION THROUGH THE
MORNING WILL KEEP MID-LEVEL CLOUD COVER DEVELOPING...AS WELL AS
SOME STIFF SSW WINDS NOT FAR OFF THE DECK /1000-1500 FT/. AN
AMDAR FLIGHT FROM RFD INDICATED 31 KT AT 1500 FT AND THESE WINDS
ARE LIKELY TO COME UP SOME BEFORE DAYBREAK AS WELL AS EXPAND
EASTWARD. AS THE WEAK SURFACE TROUGH MOVES EASTWARD AND BEGINS TO
WASH OUT...THERE WILL BE SOME WEAK INSTABILITY POOLING AHEAD OF
THIS ACROSS EASTERN IL/NW IN. ALSO...UPPER LEVEL DISTURBANCES
ALBEIT WEAK MOVING OVER THE AREA MAY JUST BE ENOUGH TO RENDER A
COUPLE STRAY SHOWERS. SOUTH WINDS WILL SEE SOME GUSTINESS
TODAY...MAINLY IN THE 15 TO 20 KT RANGE. SOUTHERLY WINDS WILL
CONTINUE ON SATURDAY WITH NO PRECIPITATION EXPECTED.

//ORD AND MDW CONFIDENCE...UPDATED 06Z...

* HIGH CONFIDENCE IN 30-35 KT SOUTHWESTERLY FLOW AT 1000-1500 FT
  THROUGH 13Z WITH MEDIUM CONFIDENCE IN THIS STAYING UNDER TRUE
  LLWS.
* LOW CONFIDENCE IN THE DEVELOPMENT OF ANY AFTERNOON SHRA BUT HIGH
  CONFIDENCE IF ANY WERE TO DEVELOP THEY WOULD BE ISOLATED.

//OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 00Z...

SATURDAY...VFR. WX NIL.

SUNDAY...CHANCE TSRA.  OTHERWISE...VFR.

MONDAY...CHANCE TSRA EARLY.  OTHERWISE...VFR.

TUESDAY...VFR. WX NIL.

WEDNESDAY...VFR. WX NIL.

MTF/KJB

&&

.MARINE...
256 AM CDT

SOUTHERLY FLOW WILL PREVAIL ACROSS THE LAKE INTO THE LATTER PART
OF THE WEEKEND...WITH STAGNANT HIGH PRESSURE OVER THE NORTHEAST
CONUS AND DEVELOPING LOW PRESSURE ACROSS SOUTHERN CANADA. AN
INITIAL WEAK AREA OF LOW PRESSURE THIS MORNING WILL MOVE NORTHEAST
ACROSS WESTERN LAKE SUPERIOR...AND THIS SHOULD RENDER WINDS TO
NEAR 30 KT AND WAVES TO 8 FT AT TIMES ACROSS THE NORTHERN PART OF
THE LAKE. THIS MAY ALSO PROVIDE SOME SCATTERED
THUNDERSTORMS...AGAIN MAINLY ACROSS THE NORTH. THE LOW ACROSS
SOUTHERN CANADA WILL DEEPEN AND MOVE NORTHEAST INTO THE
WEEKEND...STEERING A COLD FRONT EASTWARD ACROSS LAKE MICHIGAN MOST
LIKELY ON SUNDAY NIGHT. RAIN...POTENTIALLY WITH
THUNDERSTORMS...LOOK TO MOVE EAST ACROSS THE LAKE WITH THIS
FEATURE. THIS SHOULD BE AIDED BY A WEAK SURFACE LOW ALONG THE
SOUTHERN PORTION OF THIS FRONT. WHILE WINDS ARE ANTICIPATED TO
TURN WESTERLY AND EVENTUALLY NORTHERLY BEHIND THE FRONT DURING
MONDAY...SPEEDS ARE EXPECTED TO REMAIN AT OR BELOW 15 KT.

MTF

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

$$







AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 1247 AM CDT FRI AUG 24 2012

.DISCUSSION...

UPDATE...
1043 PM

FOR REST OF TONIGHT...

NO SIGNIFICANT CHANGES MADE TO FORECAST GRIDS AND DERIVED TEXT
PRODUCTS THOUGH DID DO SOME TWEAKING FOR RECENT TRENDS.

DURING THE LATER AFTERNOON TMKE RADAR DETECTED AN INCREASINGLY
DEFINED LINE OF LOW LEVEL CONVERGENCE FROM JUST OFFSHORE OF
HIGHWOOD AND LAKE BLUFF IN SOUTHEAST LAKE CO. IL BOWING OUT OVER
THE LAKE THEN CURVING BACK TO THE SHORELINE NEAR PORT WASHINGTON
IN EAST CENTRAL OZAUKEE CO. WI.

WHILE THE RUC13 HAS SHOWN SURFACE CONVERGENCE ALONG AND JUST
INLAND IN THIS AREA DUE TO A MODEST LAKE BREEZE...THE HRR3
PLACED THIS LINEAR CONVERGENT ZONE...DUE TO SPEED CONVERGENCE PER
THIS MODEL...MUCH BETTER.

SURFACE/LOW LEVEL CONVERGENCE COMBINED WITH WEAK LOW LEVEL WARM
AIR ADVECTION AND VERY MODEST MID LEVEL COOLING AND A VERY MINOR
DISTURBANCE MOVING EAST ACROSS SOUTHERN WI AND NORTHERN IL DURING
THE LATE AFTERNOON THROUGH MID EVENING COMBINED TO ALLOW CAPE
VALES TO GROW AND SHOWERS TO FORM ALONG THIS LINE. WHILE THE
SOUTHERN EXTENT OF THESE SHOWERS HAS BEEN MOVING NORTHWARD AND
WEAKENING DURING THE MID TO LATE EVENING... AT THE SAME TIME
ANOTHER SIMILAR LINE HAS APPEARED BETWEEN THE SAME END POINTS BUT
BOWING ALL THE WAY OUT TO MID LAKE OFF OF RAC AND MKE. A FEW WEAK
SHOWERS WERE ALONG THIS LINE.

PREMISED ON THE HRR CONTINUING TO DEPICT THE LINEAR CONVERGENCE
ZONE...THE AREA OF CONVERGENCE WILL SHIFT SOUTH TO OFF OF THE IL
SHORE BEFORE WEAKENING AS IT DRIFTS OUT TOWARD MID LAKE BY 06Z.
THUS THE THREAT OF SHOWERS WITH THESE FEATURES LOOKS TO BE LOW AT
BEST.

A LONE SHOWER MOVED INTO SOUTHERN LASALLE CO. EARLY THIS EVENING
THEN DISSIPATED AS IT CONTINUE TO THE NORTHEAST. THIS ISOLATED
SHOWER WAS A RESULT OF THE INCREASED LIFT ASSOCIATED WITH THE
MINOR SHORT WAVE MOVING OVER THE NORTHERN END OF AN AREA OF WELL
DEFINED MODERATE CU WITH THE LOSS OF HEATING RESULTING IN ITS
DEMISE.

FOR THE OVERNIGHT...LATEST RUNS OF NAM...RUC AND HRR ALL KEEP THE
LOCAL FORECAST AREA DRY WITH THE RAIN FALLING FROM EASTERN WI
SOUTHWESTWARD ACROSS IA. WITH A STRONGER SHORT WAVE TROUGH MOVING
EAST ACROSS MN AND FAR NORTHERN IA AT LATE EVENING AND PROGGED TO
CONTINUE EAST HAVE RETAINED THE SLIGHT CHANCE POPS ACROSS THE
NORTHERN PORTION OF THE FORECAST AREA...AND WITH THE TROUGH TO
REACH FAR EASTERN WI AND FAR NORTHEAST IL BY EARLY TO MID MORNING
HAVE LEFT THE LOW POPS DURING FRI AS IS.

TRS

//PREV DISCUSSION...
344 PM CDT

MAIN FORECAST CONCERNS/CHALLENGES THIS FORECAST PERIOD ARE WITH
CLOUD TRENDS THIS EVENING AND TONIGHT AS WELL AS FOR A SLIGHT
CHANCE OF LIGHT SHOWERS TONIGHT.

RELATIVELY QUIET BUT WARM CONDITIONS CURRENTLY ACROSS THE
CWA...WITH SOME MID/HIGH LEVEL CLOUD COVER PASSING OVERHEAD. AS
SEVERAL MID LEVEL FEATURES CONTINUE TO SHIFT EAST THIS
EVENING...SOUTHWEST MID LEVEL FLOW WILL ALLOW FOR A CONTINUED
SETUP FOR WAA TO OCCUR. ALTHOUGH THIS WAA/ASCENT WILL BE FAIRLY
WEAK...IT SHOULD BE ENOUGH TO OVERCOME SOME DRIER AIR AND ALLOW
FOR REDEVELOPMENT OF MID LEVEL CLOUDS ACROSS MUCH OF THE REGION.
ALTHOUGH NOT EXACTLY THE SAME SETUP FROM THIS MORNING...A SIMILAR
SITUATION WITH PARTLY CLOUDY/CLOUD SKIES AND SOME LIGHT SHOWERS
COULD ONCE AGAIN OCCUR...ESPECIALLY WITH SOME WEAK MID LEVEL
RIPPLES PASSING OVERHEAD AS WELL AS A LIFTING FRONTAL BOUNDARY. SO
HAVE MADE MENTION OF A SLIGHT CHANCE OF LIGHT SHOWERS TONIGHT.
THUNDER SHOULD BE NONEXISTENT ONCE AGAIN AS BETTER FORCING WILL BE
TIED MORE TOWARD A STRONGER WAVE FURTHER TO THE NORTH ACROSS
WISCONSIN TONIGHT. AS THIS WAVE SHIFTS EAST OF THE REGION FRIDAY
MORNING...ANY PRECIP/CLOUD COVER WILL EXIT AND DIMINISH MAKING WAY
FOR PARTLY CLOUDY SKIES. WITH THERMAL AXIS SHIFTING
OVERHEAD...TEMPS SHOULD RISE FAIRLY EASILY TOMORROW WITH HIGH
TEMPERATURES IN THE LOWER 90S EXPECTED. WITH SOME LOCATIONS IN THE
WESTERN CWA ALREADY OBSERVING LOWER 90S TODAY...IT WOULD NOT BE
OUT OF THE QUESTION FOR SOME MID 90S TO OCCUR AS WELL. DESPITE
THIS WARM UP...LOW HUMIDITY AND SOME SUNSHINE WILL HELP TO PROVIDE
ANOTHER PLEASANT DAY. HAVE ALSO MAINTAINED LOWER 90S INTO SATURDAY
WITH REALLY NO CHANGE IN THE OVERALL SETUP EXPECTED.

THE NEXT BEST CHANCE FOR PRECIP IS STILL APPEARING TO BE LATE IN
THE WEEKEND AS A WAVE EJECTS OUT OF THE CENTRAL PLAINS. THIS
SHOULD INDUCE SOME DECENT PRESSURE FALLS AND HELP THIS SYSTEM WRAP
SOME GOOD MOISTURE INTO IT. WITH GUIDANCE STILL VARYING ON ITS
OVERALL EVOLUTION...HAVE NOT GONE TOO HIGH WITH POPS FOR SUNDAY
BUT DID INCREASE TO HIGH CHANCE POPS FOR MOST OF THE CWA ON SUNDAY
WITH MOST GUIDANCE SPEEDING UP THIS SYSTEM. THIS SYSTEM WILL NEED
TO CONTINUE BE MONITORED...DUE TO THE OVERALL STRENGTH OF THE
CONVECTIVE POTENTIAL STILL UNKNOWN AS WELL AS CHANCES FOR SOME
DECENT RAINFALL.

RODRIGUEZ

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 06Z...

* 30-35 KT SOUTHWESTERLY FLOW AT 1000-1500 FT THROUGH 13Z.
* SMALL CHANCE FOR ISOLATED SHRA THIS AFTERNOON AND EVENING.


//DISCUSSION...UPDATED 06Z...

THE TERMINALS TODAY WILL REMAIN BETWEEN HIGH PRESSURE CENTERED
ACROSS THE NORTHEAST AND A WEAKENING LOW PRESSURE TROUGH MOVING
FROM MN TO THE UPPER GREAT LAKES. WARM AIR ADVECTION THROUGH THE
MORNING WILL KEEP MID-LEVEL CLOUD COVER DEVELOPING...AS WELL AS
SOME STIFF SSW WINDS NOT FAR OFF THE DECK /1000-1500 FT/. AN
AMDAR FLIGHT FROM RFD INDICATED 31 KT AT 1500 FT AND THESE WINDS
ARE LIKELY TO COME UP SOME BEFORE DAYBREAK AS WELL AS EXPAND
EASTWARD. AS THE WEAK SURFACE TROUGH MOVES EASTWARD AND BEGINS TO
WASH OUT...THERE WILL BE SOME WEAK INSTABILITY POOLING AHEAD OF
THIS ACROSS EASTERN IL/NW IN. ALSO...UPPER LEVEL DISTURBANCES
ALBEIT WEAK MOVING OVER THE AREA MAY JUST BE ENOUGH TO RENDER A
COUPLE STRAY SHOWERS. SOUTH WINDS WILL SEE SOME GUSTINESS
TODAY...MAINLY IN THE 15 TO 20 KT RANGE. SOUTHERLY WINDS WILL
CONTINUE ON SATURDAY WITH NO PRECIPITATION EXPECTED.


//ORD AND MDW CONFIDENCE...UPDATED 06Z...

* HIGH CONFIDENCE IN 30-35 KT SOUTHWESTERLY FLOW AT 1000-1500 FT
  THROUGH 13Z WITH MEDIUM CONFIDENCE IN THIS STAYING UNDER TRUE
  LLWS.
* LOW CONFIDENCE IN THE DEVELOPMENT OF ANY AFTERNOON SHRA BUT HIGH
  CONFIDENCE IF ANY WERE TO DEVELOP THEY WOULD BE ISOLATED.


//OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 00Z...

SATURDAY...VFR. WX NIL.

SUNDAY...CHANCE TSRA.  OTHERWISE...VFR.

MONDAY...CHANCE TSRA EARLY.  OTHERWISE...VFR.

TUESDAY...VFR. WX NIL.

WEDNESDAY...VFR. WX NIL.

MTF/KJB

&&

.MARINE...
229 PM CDT

A TROUGH OF LOW PRESSURE STRETCHING FROM SASKATCHEWAN TO THE
SOUTHERN HIGH PLAINS WILL REMAIN NEARLY STATIONARY THROUGH FRIDAY
NIGHT...WHILE A DEEP AREA OF LOW PRESSURE DEVELOPS WITHIN THE
NORTHERN PERIPHERY OF THIS TROUGH OVER SASKATCHEWAN. THIS LOW WILL
MOVE NORTHEAST ACROSS MANITOBA SATURDAY AND SATURDAY NIGHT...AND
OVER HUDSON BAY SUNDAY AND SUNDAY NIGHT. THIS WILL SET UP A
PROLONGED PERIOD OF SOUTH WINDS ACROSS LAKE MICHIGAN THROUGH THE
WEEKEND. WARM AIR SPREADING ACROSS THE LAKE ON THESE SOUTH WINDS
WILL TEND TO LIMIT THE DEPTH OF THE MIXED LAYER OVER THE WATER...
WITH MODEL FORECAST SOUNDINGS DEPICTING 15-20 KTS AND SOME GUSTS
INTO THE 20-25 KT RANGE PARTICULARLY OVER THE NORTHERN AND NORTH
CENTRAL PARTS OF THE LAKE. SOME GUIDANCE DEPICTS A WEAKER SURFACE
WAVE DEVELOPING ACROSS THE MIDWEST BY EARLY SUNDAY...ALONG THE COLD
FRONT TRAILING THE DEEPER CANADIAN LOW. SOUTH-SOUTHEAST WINDS MAY
BRIEFLY PICK UP NEAR 20 KTS ON THE SOUTHERN PORTION OF THE LAKE
AHEAD OF THIS WAVE EARLY SUNDAY. THE COLD FRONT WILL THEN TRANSLATE
EAST ACROSS LAKE MICHIGAN SUNDAY NIGHT...WITH THE GRADIENT WEAKENING
IN THE VICINITY OF THE FRONTAL TROUGH WITH WINDS SHIFTING TO THE
NORTH-NORTHWEST. WEAK HIGH PRESSURE WILL THEN SPREAD ACROSS THE
UPPER MIDWEST BEHIND THE FRONT SUNDAY NIGHT AND MONDAY...MOVING
ACROSS THE WESTERN AND NORTHERN LAKES MONDAY NIGHT AND TUESDAY.

RATZER

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

$$







AREA FORECAST DISCUSSION

NWS GOODLAND KS

 505 PM MDT SAT AUG 25 2012

.SHORT TERM...(THIS EVENING)
ISSUED AT 108 PM MDT SAT AUG 25 2012

RADAR IS SHOWING A DECREASING TREND WITH THE LIGHT PRECIPITATION.
THIS IS A RESULT OF THE MID LEVEL LOW MOVING OFF TO THE EAST.
STRONG MID LEVEL SUBSIDENCE AND DRYING MOVING INTO THE NORTHWEST
PORTION ALREADY. SO HAVE TONIGHT DRY. LIGHT UPSLOPE TO LIGHT AND
VARIABLE WINDS WILL BE IN PLACE BY LATER TONIGHT. DRIER AIR FROM
THE SURFACE THROUGH MID LEVELS WILL MOVE INTO THE WESTERN PORTION
WITH INCREASING LOW LEVEL MOISTURE IN THE EASTERN PORTION. SO HAVE
INCREASED CLOUD COVER IN THE EAST AND HAVE EXPANDED THE AREA OF
FOG FURTHER WEST AND INCREASED COVERAGE TO AREAS IN THE FAR EAST.
COOLER MINS WILL BE IN THE WEST WITH THE DRIER AIR.

.LONG TERM...(SUNDAY THROUGH SATURDAY)
ISSUED AT 225 PM MDT SAT AUG 25 2012

SUNDAY-TUESDAY...NEAR TERM MODELS IN REASONABLE AGREEMENT THAT 594
DM RIDGE WILL BEGIN TO BUILD OVER THE AREA THROUGH THE
PERIOD...GENERALLY BRINGING AN END TO THE MORE WIDESPREAD
PRECIPITATION THREAT OF THE PAST FEW DAYS. INITIAL CONCERN WILL BE
HOW QUICKLY H5 TROUGH MOVES EAST OUT OF THE AREA AND WHETHER OR IT
WILL CONTINUE TO LINGER ACROSS THE EASTERN CWA. LATEST OPERATIONAL
GUIDANCE AS WELL AS SREF DATA SUPPORT TROUGH BEING WELL TO THE EAST
OF THE CWA BY SUNDAY MORNING WITH LARGE SCALE SUBSIDENCE BRINGING AN
END TO PRECIPITATION THREAT BY SUNRISE. STRONGEST SUBSIDENCE WILL
REMAIN OVER EASTERN CWA AS SHORT WAVE TROUGH DEPARTS THE AREA WITH
FAIRLY NEUTRAL LARGE SCALE FORCING ACROSS THE WEST DESPITE SLOWLY
AMPLIFYING TROUGH. WITH NO LARGE CHANGE IN AIR MASS
EXPECTED...ATMOSPHERE WILL DESTABILIZE AS EASTERLY FLOW BRINGS 50+
TDS INTO EASTERN COLORADO ALONG SFC TROUGH. SOUNDINGS AND MIXED
LAYER CINH FIELDS SUGGEST THERE WILL BE ROUGH 50 J/KG OF CINH ACROSS
THE AREA AND WHILE PERSISTENT CONVERGENCE MAY BE ENOUGH TO INITIATE A
STORM OR TWO...CONFIDENCE IN THIS SCENARIO IS LOW. GIVEN WEAK WINDS
ALOFT STORMS WOULD STRUGGLE TO MOVE OFF ON THE INITIATION AREA FOR
MOST OF THE AFTERNOON AND LATE EVENING. OTHERWISE WITH TEMPERATURES
GRADUALLY WARMING ALOFT AND MOISTURE PROFILES DIMINISHING THROUGH
TUESDAY THINK PRECIPITATIONS CHANCES WILL BE VERY LOW UNDER LARGE
SCALE RIDGE. TEMPERATURES WILL GRADUALLY WARM THROUGH THE
PERIOD...ALTHOUGH WITH SFC TROUGH TO THE NORTHWEST AND PERSISTENT
SFC RIDGE ACROSS EASTERN CWA HAVE A FEW CONCERNS THAT COOLER AIR MASS
MAY LINGER IN THE EASTERN CWA SO HAVE NOT RAISED TEMPS ALL THAT MUCH
IN THIS AREA.

IN THE EXTENDED (TUES NIGHT-SATURDAY)...MEDIUM RANGE MODELS IN
GENERAL AGREEMENT WITH LARGE SCALE PATTERN AROUND THE CWA...BUT
SIGNIFICANT DIFFERENCES WITH THE HANDLING OF ISAAC WHICH DOES
INFLUENCE THE OVERALL PATTERN...WHICH INCREASES THE UNCERTAINTY OF
THE OVERALL FORECAST. WHILE GFS/GEM AND GEFS MEAN ARE IN GOOD
AGREEMENT...SEEING THE 12Z ECWMF DATA MAKES ME THINK THAT THERE
REMAINS A GREAT DEAL OF UNCERTAINTY WITH RESPECT TO OVERALL PATTERN
FOR THE COMING WEEK AND THINK CURRENT CONSENSUS FORECAST FOR THE
MOST PART IS REASONABLE FOR THE PERIOD. IN GENERAL...EXPECT TEMPS TO
WARM BACK INTO THE LOWER TO MID 90S UNDER LARGE SCALE RIDGE. WEAK
FRONTAL ZONE MAY IMPACT NORTHWEST CWA BRINGING A SMALL CHANCE FOR
PRECIPITATION BUT LATEST DATA DOES NOT SUPPORT MORE THAN A 10-20%
CHANCE THROUGH A MAJORITY OF THE PERIOD.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 456 PM MDT SAT AUG 25 2012

VFR TO IFR CONDITIONS ARE FORECAST FOR THE 0Z TAFS. LATEST
MODEL/MOS GUIDANCE IS SPLIT ON WHETHER FOG/STRATUS WILL DEVELOP AT
KMCK AND HOW FAR WEST IT WILL EXTEND. LATEST HRRR/NAM/SREF KEEP
THE FOG EAST OF KMCK WHILE GFS/RUC/MOS PLACE THE FOG AS FAR WEST
AS KGLD. WITH A SUCH A DISAGREEMENT BETWEEN THE VARIOUS GUIDANCE
WILL NOT ALTER THE TAFS TOO MUCH FROM THE 18Z ISSUANCE. HOWEVER
POINT SOUNDINGS FROM THE RUC ARE NOT TOO SUPPORTIVE OF LOW
VISIBILITIES AT KMCK...WITH A DRY LAYER SANDWICHED BETWEEN
SATURATION AT THE SURFACE AND ROUGHLY 1500 FT AGL. WILL WAIT UNTIL
THE 6Z TAF ISSUANCE BEFORE MAKING TOO MANY CHANGES. OTHERWISE
CONDITIONS SHOULD QUICKLY IMPROVE AFTER 12Z WITH LIGHT WINDS
THROUGH SUNDAY.

&&

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

$$

SHORT TERM...BULLER
LONG TERM...JRM
AVIATION...JTL







AREA FORECAST DISCUSSION...AMENDED

NWS ALBANY NY

 440 PM EDT FRI AUG 24 2012

.SYNOPSIS...
HIGH PRESSURE AT THE SURFACE WILL REMAIN ACROSS OUR REGION THROUGH
THE WEEKEND. AN UPPER LEVEL DISTURBANCE WILL SLIDE JUST SOUTH OF NEW
YORK STATE ON SATURDAY BUT ITS INFLUENCE COULD RESULT IN WIDELY
SCATTERED AFTERNOON SHOWERS OR THUNDERSTORMS...MAINLY ACROSS THE
HIGHER TERRAIN. A STRAY SHOWER CANNOT BE RULED ON SUNDAY BUT THE
MAJORITY OF BOTH WEEKEND DAYS WILL BE DRY WARM AND SOMEWHAT HUMID
WITH AT PARTIAL SUNSHINE.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 430 PM...NOT NEARLY AS MANY CU TODAY AS YESTERDAY. DEWPOINTS
HAVE DROPPED WELL DOWN INTO THE 50S AS MID LEVEL DRY AIR HAS WORKED
INTO THE REGION AND MIXED DOWNWARD ALTHOUGH SURFACE WINDS WERE
LIGHT. TEMPERATURES WELL QUITE WARM...WELL INTO THE 80S BUT WITH THE
LOWER DEWPOINTS...THE HEAT INDEX WAS AT OR EVEN A COUPLE OF POINTS
LOWER THAN THE ACTUAL AMBIENT TEMPERATURE.

THE LATEST EXPERIMENTAL HRRR INDICATED MODERATE TO TOWERING CU COULD
ONCE AGAIN BUILD ACROSS THE TACONICS AND POINTS EAST. HOWEVER
TODAY...DEWPOINTS WERE DEFINITELY ABOUT 5 DEGREES LOWER THAN
YESTERDAY SO RIGHT NOW...FEEL NOTHING SHOULD GROW TALL FOR ANY
SHOWER LET ALONE THUNDERSTORM ACTIVITY.

ANY AND ALL CU WILL DIMINISH AROUND SUNSET.

ANOTHER FEATURE ON THE H20 LOOP WAS AN UPPER LEVEL LOW PRESSURE OVER
THE LOWER MID ATLANTIC (VA/NC). THIS FEATURE WAS TRIGGERING
THUNDERSTORMS IN SE NC. THIS FEATURE LOOKS TO LIFT A LITTLE FURTHER
NORTHWARD IN THE NEXT 24 HOURS...BUT NOW APPEARS THE CENTER OF THE
UPPER LEVEL FEATURE (WITH SLOW COLDER AIR AND CYCLONIC FLOW) WILL
STAY MAINLY SOUTH OF OUR REGION.

THIS FEATURE WAS ATTEMPTING TO PUSH HIGH AND MID LEVEL CLOUDS INTO
OUR REGION...BUT SO ONLY THE THINNER CI HAVE INTO THE REGION. THE
CANADIAN ASTRONOMICAL CLOUD FORECAST DOES INDICATE THICKER CLOUDS
MOVING MAINLY INTO OUR SOUTHERN REGION LATER TONIGHT AND THINNER
ONES FURTHER NORTH.

DECIDED TO PLACE PATCHY FOG IN THE GRIDS AS DEWPOINTS SHOULD CLIMB
BACK TO AROUND 60 WITH LIGHT WIND SO EVEN WITH SOME HIGH CLOUDS...A
LITTLE FOG COULD FORM IN THOSE FOG PRONE AREAS.

LOOK FOR LOW TEMPERATURES OVERNIGHT AROUND 60 IN THE CAPITAL
REGION...SOUTHWARD THROUGH THE HUDSON VALLEY. MOST OTHER PLACES WILL
BE IN THE MID TO UPPER 50S...EXCEPT LOWER 50S ACROSS PORTIONS OF THE
ADIRONDACK PARK.

THE AFOREMENTIONED UPPER LEVEL SYSTEM...WHILE NOT QUITE MAKING IT
INTO REGION...MIGHT NEVERTHELESS BE JUST ENOUGH OF A FOCUS TO
TRIGGER A WIDELY SCATTERED SCATTERED SHOWERS AND THUNDERSTORMS
ACROSS MAINLY THE ELEVATED TERRAIN OF OUR AREA. MODELS INDICATE
MUCAPES CREEP UP TO ABOUT 1000 J/KG AND ANY MID LEVEL CAP SHOULD BE
DIMINISHED. PWATS CREEP UP A LITTLE AS OUR AREA WILL SEE A WEAK SSE
FLOW ADVECTING A LITTLE MORE MOISTURE INTO OUR REGION.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
THE AFOREMENTIONED UPPER LEVEL SYSTEM...WHILE NOT QUITE MAKING IT
INTO REGION...MIGHT NEVERTHELESS BE JUST ENOUGH OF A FOCUS TO
TRIGGER A WIDELY SCATTERED SCATTERED SHOWERS AND THUNDERSTORMS
ACROSS MAINLY THE ELEVATED TERRAIN OF OUR AREA. MODELS INDICATE
MUCAPES CREEP UP TO ABOUT 1000 J/KG AND ANY MID LEVEL CAP SHOULD BE
DIMINISHED. PWATS CREEP UP A LITTLE AS OUR AREA WILL SEE A WEAK SSE
FLOW ADVECTING A LITTLE MORE MOISTURE INTO OUR REGION AS A WEAK
THETA-E RIDGE SETS UP.

THE UPPER LEVEL FEATURE LOOKS TO MOVE TO SOUTHEAST LATER SATURDAY
NIGHT...REPLACED BY A RIDGE OF HIGH LATE SATURDAY EVENING THROUGH
SUNDAY NIGHT.

ANY THUNDERSTORM ACTIVITY SHOULD DIMINISH FAIRLY QUICKLY SATURDAY
EVENING LEAVING US WITH ANY PARTLY CLOUDY SOMEWHAT MUGGY NIGHT WITH
PATCHY VALLEY FOG BY EARLY SUNDAY MORNING.

SUNDAY LOOKS LIKE A MAINLY SUNNY WARM DAY WITH A TOUCH LESS HUMIDITY
THAN SATURDAY. A STRAY SHOWER OR THUNDERSTORM CANNOT BE ENTIRELY
RULED OUT OVER THE HIGHER TERRAIN...WE LEFT 20 POPS IN AREAS WITH
MEAN ELEVATIONS OF 1000 FEET OR HIGHER.

SUNDAY NIGHT...HIGH PRESSURE BEGINS TO DRIFT OFFSHORE. A WEAK
SOUTHERLY FLOW WILL SEND MORE HUMIDITY AND POSSIBLY SOME STRATUS OUR
WAY. AT THIS POINT IT LOOKS TO BE RAINFREE.

THEN ON MONDAY A PRE-FRONTAL TROUGH MIGHT BE THE FOCUS FOR SOME
CONVECTION OUT AHEAD OF COLD FRONT (THAT IS EXPECTED TO ARRIVE
MONDAY NIGHT OR EARLY TUESDAY PLEASE REFER TO THE EXTENDED PORTION
OF OUR DISCUSSION FOR MORE ON THAT FEATURE). FOR NOW...ASSIGN A 30
POP FOR AFTERNOON SHOWERS AND THUNDERSTORMS. IT IS TOO EARLY TO
REALLY ACCESS HOW STRONG (OR NOT STRONG) THEY COULD GET.

TEMPERATURES THROUGH THE SHORT TERM WILL REMAIN A LITTLE ABOVE
NORMAL...WITH HIGH TEMPERATURES GENERALLY WELL INTO THE 80S BY DAY
(CLOSER TO 80 OVER THE MOUNTAINS)...AND LOWS IN THE UPPER 50S TO MID
60S AT NIGHT.

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
GOOD CONSENSUS IN LONG RANGE GUIDANCE AND ENSEMBLES THAT A COLD
FRONT TRACKS THROUGH THE REGION MONDAY NIGHT...PERHAPS LINGERING
INTO TUESDAY...DEPENDING ON THE ULTIMATE TIMING OF THE FRONT.  SOME
DIVERGENCE IN THE GUIDANCE AND ENSEMBLES BEYOND TUESDAY...SOME OF
THE DIVERGENCE ATTRIBUTED TO FEATURES RELATED TO WHATEVER FORM ISAAC
IS IN AND WHERE IT TRACKS...WHETHER IT IS OVER LAND...WATER...STRONG
ENOUGH TO STRENGTHEN UPPER RIDGING AROUND IT...OR WEAK AND NEARLY
STATIONARY OVER THE SOUTHEAST U.S. OR IF IT GETS CAUGHT IN ANY
STEERING FLOW THAT WOULD TRACK ITS REMNANTS TOWARD THE NORTHEASTERN
U.S. OR EVEN OFFSHORE.  BASICALLY...THERE ARE STILL A LOT OF
POSSIBILITIES WITH ISAAC...AND DEPENDING ON ITS POSITION AND
STRENGTH...COULD INFLUENCE HOW MUCH COLD AIR SINKS SOUTH OUT OF
CANADA...OR LACK THEREOF...INTO OUR REGION TUESDAY THROUGH THURSDAY.

THE GENERAL CONSENSUS...REGARDLESS OF THE TEMPERATURES...IS THAT THE
WEATHER SHOULD BE DRY TUESDAY THROUGH THURSDAY...MAYBE EVEN
INCLUDING FRIDAY...DEPENDING ON THE TRACK OF WHAT IS LEFT OF ISAAC
AND DEPENDING ON TIMING AND STRENGTH OF ANOTHER COLD FRONT THAT
COULD SINK SOUTH OUT OF CANADA THE END OF NEXT WEEK. OFFICIAL
FORECAST OF REMNANTS OF ISAAC STALLING IN THE SE U.S. THROUGH FRIDAY
WITH A POTENTIAL COLD FRONT WELL NORTHWEST IN THE CENTRAL GREAT
LAKES FRIDAY MORNING. FUTURE DATA AND GUIDANCE THROUGH THIS WEEKEND
MAY FORCE SOME PERIODIC ADJUSTMENTS TO FORECASTS FOR TUESDAY THROUGH
FRIDAY.

KEEPING TUESDAY NIGHT THROUGH FRIDAY DRY BASED ON HPC FORECAST OF
REMNANTS STALLING IN THE SOUTHEASTERN U.S....UNTIL THE FINER DETAILS
OF ISAAC REMNANTS AND ANY POTENTIAL COLD FRONTS LATE NEXT WEEK ARE
KNOWN.  ACKNOWLEDGING A COOLDOWN FOR TUESDAY THROUGH THURSDAY...BUT
BEING A LITTLE CAUTIOUS ABOUT HOW MUCH OF A COOLDOWN...AGAIN...UNTIL
SOME OF THE FINE DETAILS EMERGE ON THE OVERALL UPPER PATTERN FOR
NEXT WEEK.

SO...HIGHS IN THE LOWER 70S HIGHER ELEVATIONS TO LOWER 80S IN THE
VALLEYS TUESDAY. HIGHS WEDNESDAY AND THURSDAY COOLING INTO THE UPPER
60S HIGHER ELEVATIONS TO UPPER 70S TO NEAR 80 IN THE VALLEYS. HIGH
TEMPERATURES FRIDAY BACK UP TO THE MID 70S HIGHER ELEVATIONS TO
LOWER TO MID 80S VALLEYS.

&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
NO AVIATION WEATHER RELATED PROBLEMS ARE EXPECTED THROUGH THIS
EVENING. VFR CONDITIONS WILL PREVAIL. ANY SCT FLAT BASED CU WILL
DIMINISH BY SUNSET.

LATER THIS EVENING.. .RADIATION BR/FG WILL LIKELY DEVELOP AGAIN AT
KGFL/KPSF WITH ASSOCIATED MVFR/IFR CONDITIONS. WILL MENTION MVFR
VSBY AT KPOU WITH BR SIMILAR TO WHAT HAS OCCURRED THE PAST FEW
MORNINGS. THE FOG SHOULD BURN OFF AT ALL SITES BY 12Z-13Z AND VFR
CONDITIONS SHOULD PREVAIL AFTERWARD.

WINDS SHOULD BE LIGHT AND VARIABLE THROUGH TONIGHT...THEN BECOME
LIGHT SOUTH TO SOUTHEAST TOMORROW AT 6 KT OR LESS.

OUTLOOK...
SAT-SUN...VFR...ISOLD -SHRA/-TSRA.
MON...VFR...ISOLD-SCT SHRA/TSRA.
TUE...VFR/MVFR SCT -SHRA WITH ISOLD -TSRA.
WED...VFR. NO SIG WX.

&&

.FIRE WEATHER...
NO SIGNIFICANT FIRE WEATHER RELATED ISSUES THROUGH SUNDAY WITH A
SLIGHT CHANCE OF A SHOWER OR THUNDERSTORM EACH AFTERNOON. MANY
PLACES WILL NOT RECEIVE ANY RAINFALL.

RELATIVE HUMIDITY WILL RECOVER TO BETWEEN 85 AND 100 PERCENT
OVERNIGHT WITH HEAVY DEW FORMATION...AND DROP TO 45 TO 60 PERCENT ON
SATURDAY...35 TO 50 PERCENT ON SUNDAY.

THE WIND WILL BE LIGHT VARIABLE GENERALLY UNDER 10 MPH.

THE NEXT CHANCE FOR MORE NUMEROUS SHOWERS LOOKS TO BE LATE MONDAY.

&&

.HYDROLOGY...
NO HYDRO PROBLEMS ARE EXPECTED FOR THE NEXT FIVE DAYS.

DRY WEATHER IS EXPECTED TONIGHT AND AGAIN SATURDAY NIGHT THROUGH
SUNDAY NIGHT. THE BEST CHANCES FOR PRECIPITATION WILL BE SATURDAY
AFTERNOON INTO EARLY SATURDAY EVENING AS AN UPPER LEVEL DISTURBANCE
SLIDING TO OUR SOUTH PRODUCES WIDELY SCATTERED TO SCATTERED SHOWERS
ALONG WITH A FEW EMBEDDED THUNDERSTORMS. THE PRECIPITATION IS
EXPECTED TO BE MAINLY CONFINED TO THE HIGHER ELEVATIONS. THERE WILL
BE ANOTHER CHANCE OF SHOWERS AND A FEW EMBEDDED THUNDERSTORMS MONDAY
AFTERNOON INTO TUESDAY ALONG AND AHEAD OF A COLD FRONT MOVING
THROUGH THE REGION. TOTAL AVERAGE RIVER BASIN QPF AMOUNTS THROUGH
TUESDAY ARE GENERALLY EXPECTED TO BE LESS THAN A QUARTER OF AN
INCH...ALTHOUGH LOCALIZED HIGHER AMOUNTS ARE POSSIBLE IN
THUNDERSTORMS. THIS PRECIPITATION IS EXPECTED TO HAVE LITTLE IF ANY
IMPACT ON STREAMS AND RIVERS.

FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.

&&

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.

&&

$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...NAS
AVIATION...NAS
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV/FRUGIS/11


INCLUDES THE LONG TERM DISCUSSION.












AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 353 PM EDT FRI AUG 24 2012

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 348 PM EDT FRI AUG 24 2012

12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A GENERAL ZONAL
FLOW OVER THE NRN TIER CONUS/SRN CANADA. A SHRTWV EMBEDDED IN THIS
FLOW IS PRESENT OVER WI/UPR MI EARLY THIS AFTN AND HAS BEEN
SUPPORTING SOME ISOLD -SHRA/A FEW TS OVER MAINLY THE E HALF OF THE
CWA DESPITE PRESENCE OF DRY LLVL AIR SHOWN ON THE 12Z GRB/APX RAOBS
THAT EXTENDS WELL TO THE S AS DEPICTED ON THE 12Z RAOB FM QUAD
CITIES IOWA. OVER THE W HALF...NVA IN THE WAKE OF THE SHRTWV AND
AGGRESSIVE DRYING FOCUSED AT H5-7 WITH ENEWD SPREAD OF AIRMASS SHOWN
ON THE 12Z MPX RAOB HAS SUPPRESSED SHRA AND RESULTED IN SOME CLRG IN
DESPITE PERSISTENCE OF AXIS OF HIER H85 DEWPTS/THETA-E IN THAT AREA
PER RUC ANALYSIS. SHRTWV RDG AXIS OVER MN IS BRINGING DRY WX THERE
ALONG WITH MOCLR SKIES...BUT MORE CLDS AND SOME SHRA/TS ARE OVER THE
NRN PLAINS IN ADVANCE OF POTENT SHRTWV MOVING EWD THRU SRN ALBERTA.

LATE THIS AFTN...DESPITE NVA/AGGRESSIVE UPR DRYING IN THE WAKE OF
SLOW MOVING SHRTWV...SUSPECT SOME SHRA/TS MAY DVLP ON THE LEADING
EDGE OF THE H5-7 DRYING WHERE MORE INSOLATION WL COINCIDE WITH AREA
OF HIER H85 DEWPTS. A NUMBER OF THE RECENT HIER RES MODELS SHOW AT
LEAST ISOLD-SCT SHRA/TS DVLPG OVER THE CENTRAL ZNS...SO PAINTED AN
AXIS OF SOMEWHAT HIER CHC POPS IN THIS AREA. THE FAR W SHOULD BE DRY
UNDER MUCH DRIER H7-5 AIR AND WITH SOME MODERATION NEAR LK SUP.
LINGERING LLVL DRY AIR OVER THE E SHOULD ALSO LIMIT POPS IN THAT
AREA DESPITE MORE MID LVL MSTR THAT MIGHT SUPPORT PERSISTENT -SHRA.

TNGT...AS DEEPER SHRTWV OVER SW CANADA THIS MRNG DRIFTS EWD AND
SHRTWV OVER THE AREA SHIFTS TO THE E...ARRIVAL OF SHRTWV RDG FM MN/
ASSOCIATED H5 RISES IN CONCERT WITH LOSS OF DAYTIME HEATING SHOULD
CAUSE ANY EVNG SHRA/TS OVER MAINLY THE E AND CENTRAL ZNS TO
DISSIPATE. PCPN CHCS WL LINGER LONGEST OVER THE E CLOSER TO
DEPARTING SHRTWV/WHERE MID LVL MSTR REMAINS MOST ABUNDANT LONGEST.
ALTHOUGH THERE WAS QUITE A BIT OF FOG LAST NGT OVER MN...THE 12Z
NAM/LOCAL WRF-ARW SHOW PERSISTENT SSW LLVL FLOW DRAWING DRIER AIR
SHOWN ON THE 12Z GRB/QUAD CITY RAOBS INTO THE FA. SO EXPECT NO FOG
TO IMPACT THE CWA. DESPITE THE DRYING COLUMN...STEADY S WIND SHOULD
LIMIT THE DIURNAL TEMP FALL AT MOST SPOTS...FURTHER LIMITING THE
POTENTIAL FOR FOG.

SAT...FOCUS TURNS TO HOW QUICKLY STRONG DISTURBANCE OVER SW CANADA
THIS MRNG MIGHT INFLUENCE THE WX ESPECIALLY OVER THE WRN CWA. THE
DAY SHOULD AT LEAST START MOSUNNY WITH SHRTWV RDG AXIS/DRY H85-5
AIRMASS OVHD. BY 00Z SUN...THE SHRTWV IS PROGGED TO DRIFT NEWD TO
NEAR LK WINNIPEG AND BECOME OCCLUDED WITH H5 CUTOFF NEARLY OVER
992MB SFC LO. SINCE LLVL SLY FLOW IS FCST TO ADVECT THE DRIER
SFC-H85 AIR NOTED TO THE S OVER THE CWA THRU THE DAY AND BULK OF
DEEP LYR QVECTOR CNVGC OVER WARM CONVEYOR BELT MSTR/ATTENDANT SFC
COLD FNT ARE PROGGED TO RACH ONLY THE FAR W BY 00Z SUN...OPTED TO
SLOW DOWN EWD PUSH OF ACCOMPANYING POPS. GIVEN THE STRENGTH OF THE
SHRTWV TO THE W...PREFER THE HIER H85 FCST TEMPS BY THE NAM...WHICH
SHOWS THIS TEMP REACHING 20C OVER THE CWA VERSUS ONLY 17C BY THE
GFS. DEEP MIXING ON THE NAM FCST SDNGS YIELDS HI TEMPS REACHING ARND
90. MAX TEMPS WL BE HIEST NEAR LK SUP WHERE SLY FLOW DOWNSLOPES AND
LIMITS AND MODERATION OFF LK SUP. IN FACT...SOME RECORD HI TEMPS MAY
FALL ON SAT. AREAS DOWNWIND OF LK MI WL BE COOLEST. WITH SFC DEWPTS
LIKELY TO MIX OUT TO ARND 50 AWAY FM LK MODERATION...MIN RH WL DIP
AS LO AS 25 PCT IN THE PRESENCE OF WIND GUSTS TO 20-25 MPH ENHANCED
BY THE MIXING. FORTUNATELY...RECENT RAINS HAVE MOISTENED THE GROUND
SUFFICIENTLY TO MINIMIZE ANY FIRE WX IMPACTS.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 348 PM EDT FRI AUG 24 2012

AN UPPER-LEVEL TROUGH AND SLOW-MOVING COLD FRONT WILL CONTINUE TO
BRING RAIN AND THUNDERSTORM CHANCES TO UPPER MI THROUGH MONDAY
BEFORE DRY AND WARMER WEATHER RETURNS UNDER HIGH PRESSURE FOR THE
MIDDLE OF THE WEEK.

SATURDAY NIGHT THROUGH SUNDAY NIGHT...A SHARP TROUGH CURRENTLY
MOVING THROUGH ALBERTA AND NORTHERN MT WILL SHIFT EAST THROUGH
SATURDAY AND INDUCE A STRONG SFC LOW OVER SOUTHERN SASKATCHEWAN. BY
SATURDAY NIGHT...THE TROUGH WILL BE LIFTING TO THE NORTHEAST THROUGH
MANITOBA WHILE BECOMING NEARLY STACKED WITH THE ASSOCIATED SFC LOW.
A COLD FRONT EXTENDING FROM A NEW OCCLUSION OVER WESTERN ONTARIO
WILL BE SURGING EASTWARD THROUGH MN SATURDAY AFTERNOON. THERE IS
VERY GOOD MODEL AGREEMENT THAT THIS COLD FRONT WILL REACH THE
WESTERN TIP OF THE CWA BY 06Z SUNDAY...THEN WASH OUT ACROSS THE
CENTRAL CWA BY SUNDAY AFTERNOON AS IT LOSES SUPPORT FROM THE
WEAKENING STACKED LOW. A SECONDARY SFC TROUGH WILL THEN CATCH UP TO
THE FRONT AND HELP KICK IT OUT OF THE CWA BY SUNDAY EVENING.

NOT TOO CONFIDENT ON WIDESPREAD PRECIP CHANCES ATTM FOR SEVERAL
REASONS. FIRST...BEST Q-VECTOR CONVERGENCE WILL EXIST NORTH CLOSER
TO THE MID-LEVEL LOW...AND SOUTH WHERE A SHORTWAVE TROUGH WILL BE
MOVING INTO THE MID-MS VALLEY FROM THE SOUTHERN PLAINS. NEXT...THE
SFC LOW FORMING IN RESPONSE TO THE SOUTHERN PLAINS TROUGH WILL
LIKELY CUTOFF A SIGNIFICANT PORTION OF THE MOISTURE SUPPLY AHEAD OF
THE FRONT. THUS...APPRECIABLE MOISTURE WILL BE CONFINED TO THE NEAR
SFC LAYER OVER UPPER MI. ANY PRECIP THAT FORMS WILL BE FORCED BY A
BAND OF H8-H7 FRONTOGENESIS ALONG THE FRONT...THOUGH MOISTURE WILL
BE LACKING IN THIS LAYER. CUT BACK POPS TO LOW CHANCE FOR MUCH OF
THE LAND...WITH HIGHER POPS OVER THE WESTERN LAKE AS IT WILL BE
CLOSER TO BETTER FORCING FROM THE LOW. SOME SFC HEATING WILL AID
DEVELOPMENT OF NEW SHOWERS AND THUNDERSTORMS IN THE AFTERNOON ACROSS
THE EAST HALF...BUT ONCE AGAIN...A LACK OF MOISTURE WILL STILL BE A
CONCERN.

INCREASED/DECREASED HIGHS IN THE WEST/EAST FOR SUNDAY TO ACCOUNT FOR
CLOUD AND PRECIP TRENDS. EXPECTATION IS THAT CLOUDS WILL QUICKLY
CLEAR WEST IN THE MORNING. H8 TEMPS WILL COOL TO AROUND 14C WITH
THIS CLEARING...BUT SHOULD STILL BE WARM ENOUGH TO PRODUCE LOW 80S
FOR HIGHS. PATCHY FOG COULD BE POSSIBLE FOR THE INTERIOR WEST SUNDAY
NIGHT...BUT DRY AIR ADVECTING INTO THE AREA SHOULD BE ENOUGH TO
SUBDUE THE THREAT.

MONDAY AND MONDAY NIGHT...AS THE MID-LEVEL LOW DRIFTS NORTHEASTWARD
TO HUDSON BAY SUNDAY NIGHT...IT WILL TAP INTO SOME ENERGY FROM THE
RAGGED POLAR VORTEX OVER NORTHERN NUNAVUT. THE REINFORCED TROUGH AND
WEAK SFC TROUGH ARE THEN PROGGED TO AFFECT THE AREA MONDAY NIGHT.
MODELS BEGIN TO DIVERGE SIGNIFICANTLY BY THIS POINT...BUT VERY
LITTLE MOISTURE ABOVE THE SFC MIXED LAYER WILL LIKELY PREVENT ANY
PRECIP. EVEN MORE...DO NOT EXPECT MUCH CLOUD COVER EXCEPT FOR
POSSIBLE AFTERNOON CUMULUS. HIGHS WILL BE IN THE 70S...WITH THE
COOLEST TEMPS NORTH CLOSER TO A H8 TEMP MIN IN NORTHERN ONTARIO.

TUESDAY THROUGH THURSDAY...A VERY IMPRESSIVE RIDGE WILL SLOWLY EDGE
INTO THE UPPER GREAT LAKES BEGINNING TUESDAY...WITH THE SFC HIGH
PRESSURE CENTERING ITSELF OVER WI/UPPER MI BY WEDNESDAY MORNING. THE
HIGH WILL CONTINUE TO GRADUALLY DRIFT SOUTHEASTWARD WEDNESDAY
THROUGH THURSDAY...WITH UPPER MI REMAINING UNDER ITS INFLUENCE.
INCREASED HIGHS THROUGH FRIDAY AS THERE WILL BE PLENTY OF SUN AND
WARM H8 TEMPS. ISENTROPIC LIFT ON THE 305-310 THEATA SFCS IN
ADDITION TO H8 MOISTURE TRANSPORT MAY RESULT IN A FEW SHOWERS AND
THUNDERSTORMS WEDNESDAY NIGHT...MAINLY NORTH.

FRIDAY...THERE IS MODEL AGREEMENT THAT THE RIDGE WILL BEGIN TO BREAK
DOWN BY EARLY FRIDAY. THE GFS IS ONCE AGAIN MORE AGGRESSIVE THAN THE
ECMWF WITH A TROUGH FROM BRITISH COLUMBIA MOVING INTO THE RIDGE. IT
IS DIFFICULT TO SAY WHICH MODEL WILL PAN OUT...IF EITHER...SO WILL
GO WITH A MODEL CONSENSUS FOR THE FORECAST.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 125 PM EDT FRI AUG 24 2012

ALTHOUGH THERE COULD BE SOME -SHRA AND EVEN A TS AT SAW THIS AFTN...
EXPECT VFR CONDITIONS AT ALL 3 SITES THRU THIS FCST PERIOD WITH
RELATIVELY DRY LLVL AIR IN PLACE.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 348 PM EDT FRI AUG 24 2012

EXCEPT FOR A STRONGER S WIND UP TO 25 KTS OVER THE E INTO THIS
EVENING AHEAD OF AN APPROACHING LO PRES TROF...WINDS THRU THE
FORECAST PERIOD WILL BE NO HIER THAN 20 KTS AS THE COMBINATION OF A
WEAK PRES GRADIENT AND HIER OVERWATER STABILITY LIMIT WIND SPEEDS.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...KC
LONG TERM...TK
AVIATION...KC
MARINE...KC







AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 126 PM EDT FRI AUG 24 2012

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 523 AM EDT FRI AUG 24 2012

00Z RAOBS AND RUC ANALYSIS INDICATES ZONAL FLOW ALOFT DOWNSTREAM OF
SHARP TROUGH OVER WESTERN CANADA AND ON PERIPHERY OF BROAD RIDGE
OVER CENTRAL CONUS. AT THE SFC...DISJOINTED COMPLEX OF TROUGHS ARE
PRESENT FROM SAKSATCHEWAN INTO NORTH DAKOTA.

HAVE A DOWNRIGHT MESS OF CONVECTION OVER UPR LAKES THIS MORNING
AHEAD OF PAIR OF STRONGER SHORTWAVE TROUGHS MOVING INTO NORTHWEST
ONTARIO AND INTO SOUTHWEST WISCONSIN. H85 WARM ADVECTION IS
SUPPORTING MORE WEST-TO-EAST ORIENTED SHRA/TSRA OVR LK SUPERIOR
WHILE HEIGHT FALLS AND H85-H7 MOISTURE ADVECTION ALONG 2-5KM MUCAPE
RIBBON AND ALONG WEST EDGE OF H85 JET IS SPURRING ON MULTIPLE
CLUSTERS OF MODERATE-HEAVY SHRA/TSRA FROM SOUTHWEST LK SUPERIOR INTO
NORTHWEST WI AND INTO SOUTHWEST WI. ACTIVITY OVR SOUTHWEST WI IS
MORE ORGANIZED WITH SHARPER HEIGHT FALLS OVR THAT AREA DUE TO
SHORTWAVE. ENTIRE AREA IS WITHIN INFLUENCE OF BROAD DIVERGENCE
ALOFT AS H3 JET STREAK SURGES IN FROM THE NORTHERN PLAINS.

CURRENT RADAR TRENDS AND EXPECTED POSITION OF LOW-LEVEL JET THROUGH
MID MORNING SUGGESTS THAT SHRA/TSRA OVER WESTERN LK SUPERIOR WILL
LIFT ACROSS KEWEENAW AND REST OF LK SUPERIOR THIS MORNING. IT APPEARS
THAT CONVECTION OVER SOUTHWEST WISCONSIN WILL NOT MAKE MUCH PUSH
INTO UPR MICHIGAN AS PRIMARY SHORTWAVE STAYS MAINLY OVR WISCONSIN.
LOOKS LIKE MAIN EFFECT OF BOTH AREAS OF CONVECTION WILL BE TO KEEP
SCT-BKN MID CLOUDS IN OVER MOST CWA THIS MORNING...BUT DO EXPECT
SOME HEATING. BETTER HEATING OCCURS EARLY TO MID AFTN AND COULD TIME
OUT WELL WITH ARRIVAL OF SURGE OF H85-H7 MOISTURE FROM THE SOUTHWEST.
THERE IS CURRENTLY A VERY SHARP EDGE TO THE H7 MOISTURE AS SEEN WITH
ABRUPT CLEARING SEEN OVER SOUTHERN MINNESOTA. SREF /WHICH HAS OKAY
HANDLE ON CURRENT CONVECTIVE TRENDS/ BLASTS THIS DRY MID-LEVEL AIR
INTO WEST THIRD BY EARLY AFTN WITH MOISTURE GRADIENT SETTING UP OVR
CENTRAL CWA. DEPENDING ON EXTENT OF HEATING...INSTABILITY COULD
INCREASE WITH ML BASED CAPES OVR 1000 J/KG IN THE CNTRL CWA 18Z-22Z.
TRIGGER WOULD BE SHORTWAVE TROUGH AND SFC-H85 THETA-E ADVECTION AND
MAYBE DEVELOPING LK BREEZES /THOUGH WITH FAIRLY STRONG 950MB INTO
AFTN NOT AS CONFIDENT IN THIS POSSIBLE TRIGGER/. DEEP LAYER SHEAR
ENDS UP AROUND 30 KTS DURING THE AFTN...SO AT LEAST BRIEF
ORGANIZATION/STRONG STORMS SEEMS POSSIBLE GIVEN THE INSTABILITY.
OVERALL...THINK SETUP CONTINUES TO JUSTIFY GOING FCST OF SCT POPS
MAINLY IN THE AFTN...HIGHEST OVER CENTRAL CWA. CONTINUED TO TRIM
POPS OVER WEST...JUST TOO MUCH DRYING TO TRIGGER ANY ADDITIONAL
CONVECTION THERE. BASED ON CURRENT RADAR/SATELLITE TRENDS...THINK
CLEARING IS LIKELY OVR MOST OF CWA THROUGH THE MORNING. SO...WARMER
TEMPS AS NAM INDICATES ARE PREFERRED. BASED ON MIXING TO H85 TEMPS
NEAR +19C...MAX TEMPS MAY TOP OUT WELL INTO THE UPPER 80S. WARM
START TO THE DAY WILL NOT HINDER THIS PROCESS EITHER.

SHORTWAVE TROUGH/MOISTURE ADVECTION CRUISES EAST EARLY THIS EVENING
AND OTHER THAN SOME SMALL CHANCES HAVE PRETTY MUCH ENDED POPS BTWN
00Z-06Z FOR ALL BUT EAST AND SOUTH FRINGES OF CWA. NAM IS QUITE
BULLISH ON POPS FOR OVERNIGHT TONIGHT...MUCH MORE SO THAN OTHER
MODELS. LOOKING AT SOUNDINGS...MOISTURE IS BACK ON THE INCREASE
ALOFT /ROUGHLY ABOVE H7/. LAPSE RATES KIND OF STEEP H7-H5...TOWARD
7C/KM. A LOT OF DRY AIR BLO H7 AND STRONG LIFT LOOKS TO BE LACKING.
MAY SEE A WEAK SHORTWAVE STREAKING OUT AHEAD OF DEEPER WESTERN
CANADA TROUGH WHICH COULD ENHANCE LIFT. KEPT ISOLD MENTION FOR
SHRA/TSRA OVER NORTH TWO-THIRDS OF CWA OUT INTO LK SUPERIOR ALONG
AND NORTH OF H85 FRONT...BUT EVEN THIS POSSIBILITY WILL DIMINISH
LATE IN THE NIGHT AS H7 MOISTURE TRANSPORT WEAKENS AS DOES UVM IN
THE H7-H5 LAYER. SHOULD BE ANOTHER WARM NIGHT /READINGS IN THE 60S/
DUE TO PERSISTENT SOUTH WINDS OUT AHEAD OF SFC LOW DEEPENING OVR
CANADIAN PRAIRIES.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 523 AM EDT FRI AUG 24 2012

SATURDAY...AS THE MID LEVEL LOW OVER SASK LIFTS INTO NORTHERN
MANITOBA RIDGING WILL PREVAIL DOWNSTREAM OVER THE GREAT LAKES. AS A
RESULT...DRY MID LEVELS AND CAPPNIG SHOULD LIMIT ANY PCPN
CHANCES...PER ECMWF/GFS. HOWEVER...SINCE THE REGIONAL GEM AND NAM
CONTINUE TO SUGGEST THAT A WEAK SHORTWAVE TROUGH LIFTING OUT OF THE
UPPER MS VALLEY COULD BRING SOME PCPN INTO THE WEST...SLIGHT CHANCE
WAS MENTIONED IN THE LATE AFTERNOON. WITH PLENTY OF SUNSHINE/MIXING
AND 850 MB TEMPS INTO THE 18C-20C RANGE...EXPECT MAX READINGS INTO
THE UPPER 80S WITH A FEW 90S POSSIBLE IN SW FLOW DOWNSLOPE LOCATIONS.

SATURDAY NIGHT AND SUNDAY...THE MODELS SUGGEST THAT THE STRONGER
FORCING AND HEIGHT FALLS AHEAD OF THE MID LEVEL LOW WILL REMAIN
NORTH OF UPPER MICHIGAN WHILE A WEAKER SHORTWAVE MOVING OUT OF THE
CNTRL PLAINS AND GREATER INSTABILITY WILL REMAIN TO THE SOUTH.
SO...THE DRIER QPF FROM THE ECMWF/GEM SCENARIO WAS PREFERRED
COMPARED TO THE GFS. NEVERTHELESS...SCT SHRA/TSRA ARE STILL EXPECTED
AS THE SFC TROUGH AND AXIS OF HIGHER MOISTURE MOVE THROUGH THE CWA.
ANY LINGERING PCPN SHOULD EXIT THE CNTRL CWA SUN EVENING AND THE
EAST OVERNIGHT.

MON-THU...THE MODELS WERE IN GENERAL AGREEMENT WITH TREND TOWARD
PATTERN AMPLIFICATION AS A TROUGH MOVES INTO THE WRN CONUS AND RIDGE
DEVELOPS FROM THE CNTRL ROCIES INTO THE PLAINS. THE NW FLOW PATTERN
INTO THE UPPER GREAT LAKES WILL BRING A SFC HIGH AND COOLER DRIER
AIR INTO UPPER MI MON-TUE WHICH WOULD GIVE WAY TO WARMING BY
WED-THU. CONFIDENCE IN PCPN POTENTIAL BY WED-THU WITH POTENTIAL
FRONTAL SYSTEM AND HEIGHT FALLS IS LOW GIVEN INCREASING MODEL SPREAD
AND RUN TO RUN VARIATION WITH THE STRENGTH OF THE RIDGE. SO
CONSENSUS SLIGHT CHANCE POPS WERE NOT ALTERED.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 125 PM EDT FRI AUG 24 2012

ALTHOUGH THERE COULD BE SOME -SHRA AND EVEN A TS AT SAW THIS AFTN...
EXPECT VFR CONDITIONS AT ALL 3 SITES THRU THIS FCST PERIOD WITH
RELATIVELY DRY LLVL AIR IN PLACE.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EDT FRI AUG 24 2012

SOUTH TO SOUTHEAST WINDS REMAIN STRONG TODAY ESPECIALLY OVER EASTERN
SECTIONS WHERE GUSTS MAY REACH 25-30 KTS AT HIGHER PLATFORMS AND
SHIP LEVEL. LOW-LEVEL JET AXIS FADES AWAY TONIGHT...SO WINDS SHOULD
DECREASE TO LESS THAN 20 KTS. WINDS EXPECTED TO REMAIN AT 20 KTS OR
LESS THROUGH THE UPCOMING WEEKEND AND INTO EARLY NEXT WEEK AS
STRONGEST PRESSURE GRADIENT STAYS WELL TO NORTH IN THE VICINITY OF
STRONG SFC LOW OVER HUDSON BAY.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...JLA
LONG TERM...JLB
AVIATION...KC
MARINE...JLA







AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 754 AM EDT FRI AUG 24 2012

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 523 AM EDT FRI AUG 24 2012

00Z RAOBS AND RUC ANALYSIS INDICATES ZONAL FLOW ALOFT DOWNSTREAM OF
SHARP TROUGH OVER WESTERN CANADA AND ON PERIPHERY OF BROAD RIDGE
OVER CENTRAL CONUS. AT THE SFC...DISJOINTED COMPLEX OF TROUGHS ARE
PRESENT FROM SAKSATCHEWAN INTO NORTH DAKOTA.

HAVE A DOWNRIGHT MESS OF CONVECTION OVER UPR LAKES THIS MORNING
AHEAD OF PAIR OF STRONGER SHORTWAVE TROUGHS MOVING INTO NORTHWEST
ONTARIO AND INTO SOUTHWEST WISCONSIN. H85 WARM ADVECTION IS
SUPPORTING MORE WEST-TO-EAST ORIENTED SHRA/TSRA OVR LK SUPERIOR
WHILE HEIGHT FALLS AND H85-H7 MOISTURE ADVECTION ALONG 2-5KM MUCAPE
RIBBON AND ALONG WEST EDGE OF H85 JET IS SPURRING ON MULTIPLE
CLUSTERS OF MODERATE-HEAVY SHRA/TSRA FROM SOUTHWEST LK SUPERIOR INTO
NORTHWEST WI AND INTO SOUTHWEST WI. ACTIVITY OVR SOUTHWEST WI IS
MORE ORGANIZED WITH SHARPER HEIGHT FALLS OVR THAT AREA DUE TO
SHORTWAVE. ENTIRE AREA IS WITHIN INFLUENCE OF BROAD DIVERGENCE
ALOFT AS H3 JET STREAK SURGES IN FROM THE NORTHERN PLAINS.

CURRENT RADAR TRENDS AND EXPECTED POSITION OF LOW-LEVEL JET THROUGH
MID MORNING SUGGESTS THAT SHRA/TSRA OVER WESTERN LK SUPERIOR WILL
LIFT ACROSS KEWEENAW AND REST OF LK SUPERIOR THIS MORNING. IT APPEARS
THAT CONVECTION OVER SOUTHWEST WISCONSIN WILL NOT MAKE MUCH PUSH
INTO UPR MICHIGAN AS PRIMARY SHORTWAVE STAYS MAINLY OVR WISCONSIN.
LOOKS LIKE MAIN EFFECT OF BOTH AREAS OF CONVECTION WILL BE TO KEEP
SCT-BKN MID CLOUDS IN OVER MOST CWA THIS MORNING...BUT DO EXPECT
SOME HEATING. BETTER HEATING OCCURS EARLY TO MID AFTN AND COULD TIME
OUT WELL WITH ARRIVAL OF SURGE OF H85-H7 MOISTURE FROM THE SOUTHWEST.
THERE IS CURRENTLY A VERY SHARP EDGE TO THE H7 MOISTURE AS SEEN WITH
ABRUPT CLEARING SEEN OVER SOUTHERN MINNESOTA. SREF /WHICH HAS OKAY
HANDLE ON CURRENT CONVECTIVE TRENDS/ BLASTS THIS DRY MID-LEVEL AIR
INTO WEST THIRD BY EARLY AFTN WITH MOISTURE GRADIENT SETTING UP OVR
CENTRAL CWA. DEPENDING ON EXTENT OF HEATING...INSTABILITY COULD
INCREASE WITH ML BASED CAPES OVR 1000 J/KG IN THE CNTRL CWA 18Z-22Z.
TRIGGER WOULD BE SHORTWAVE TROUGH AND SFC-H85 THETA-E ADVECTION AND
MAYBE DEVELOPING LK BREEZES /THOUGH WITH FAIRLY STRONG 950MB INTO
AFTN NOT AS CONFIDENT IN THIS POSSIBLE TRIGGER/. DEEP LAYER SHEAR
ENDS UP AROUND 30 KTS DURING THE AFTN...SO AT LEAST BRIEF
ORGANIZATION/STRONG STORMS SEEMS POSSIBLE GIVEN THE INSTABILITY.
OVERALL...THINK SETUP CONTINUES TO JUSTIFY GOING FCST OF SCT POPS
MAINLY IN THE AFTN...HIGHEST OVER CENTRAL CWA. CONTINUED TO TRIM
POPS OVER WEST...JUST TOO MUCH DRYING TO TRIGGER ANY ADDITIONAL
CONVECTION THERE. BASED ON CURRENT RADAR/SATELLITE TRENDS...THINK
CLEARING IS LIKELY OVR MOST OF CWA THROUGH THE MORNING. SO...WARMER
TEMPS AS NAM INDICATES ARE PREFERRED. BASED ON MIXING TO H85 TEMPS
NEAR +19C...MAX TEMPS MAY TOP OUT WELL INTO THE UPPER 80S. WARM
START TO THE DAY WILL NOT HINDER THIS PROCESS EITHER.

SHORTWAVE TROUGH/MOISTURE ADVECTION CRUISES EAST EARLY THIS EVENING
AND OTHER THAN SOME SMALL CHANCES HAVE PRETTY MUCH ENDED POPS BTWN
00Z-06Z FOR ALL BUT EAST AND SOUTH FRINGES OF CWA. NAM IS QUITE
BULLISH ON POPS FOR OVERNIGHT TONIGHT...MUCH MORE SO THAN OTHER
MODELS. LOOKING AT SOUNDINGS...MOISTURE IS BACK ON THE INCREASE
ALOFT /ROUGHLY ABOVE H7/. LAPSE RATES KIND OF STEEP H7-H5...TOWARD
7C/KM. A LOT OF DRY AIR BLO H7 AND STRONG LIFT LOOKS TO BE LACKING.
MAY SEE A WEAK SHORTWAVE STREAKING OUT AHEAD OF DEEPER WESTERN
CANADA TROUGH WHICH COULD ENHANCE LIFT. KEPT ISOLD MENTION FOR
SHRA/TSRA OVER NORTH TWO-THIRDS OF CWA OUT INTO LK SUPERIOR ALONG
AND NORTH OF H85 FRONT...BUT EVEN THIS POSSIBILITY WILL DIMINISH
LATE IN THE NIGHT AS H7 MOISTURE TRANSPORT WEAKENS AS DOES UVM IN
THE H7-H5 LAYER. SHOULD BE ANOTHER WARM NIGHT /READINGS IN THE 60S/
DUE TO PERSISTENT SOUTH WINDS OUT AHEAD OF SFC LOW DEEPENING OVR
CANADIAN PRAIRIES.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 523 AM EDT FRI AUG 24 2012

SATURDAY...AS THE MID LEVEL LOW OVER SASK LIFTS INTO NORTHERN
MANITOBA RIDGING WILL PREVAIL DOWNSTREAM OVER THE GREAT LAKES. AS A
RESULT...DRY MID LEVELS AND CAPPNIG SHOULD LIMIT ANY PCPN
CHANCES...PER ECMWF/GFS. HOWEVER...SINCE THE REGIONAL GEM AND NAM
CONTINUE TO SUGGEST THAT A WEAK SHORTWAVE TROUGH LIFTING OUT OF THE
UPPER MS VALLEY COULD BRING SOME PCPN INTO THE WEST...SLIGHT CHANCE
WAS MENTIONED IN THE LATE AFTERNOON. WITH PLENTY OF SUNSHINE/MIXING
AND 850 MB TEMPS INTO THE 18C-20C RANGE...EXPECT MAX READINGS INTO
THE UPPER 80S WITH A FEW 90S POSSIBLE IN SW FLOW DOWNSLOPE LOCATIONS.

SATURDAY NIGHT AND SUNDAY...THE MODELS SUGGEST THAT THE STRONGER
FORCING AND HEIGHT FALLS AHEAD OF THE MID LEVEL LOW WILL REMAIN
NORTH OF UPPER MICHIGAN WHILE A WEAKER SHORTWAVE MOVING OUT OF THE
CNTRL PLAINS AND GREATER INSTABILITY WILL REMAIN TO THE SOUTH.
SO...THE DRIER QPF FROM THE ECMWF/GEM SCENARIO WAS PREFERRED
COMPARED TO THE GFS. NEVERTHELESS...SCT SHRA/TSRA ARE STILL EXPECTED
AS THE SFC TROUGH AND AXIS OF HIGHER MOISTURE MOVE THROUGH THE CWA.
ANY LINGERING PCPN SHOULD EXIT THE CNTRL CWA SUN EVENING AND THE
EAST OVERNIGHT.

MON-THU...THE MODELS WERE IN GENERAL AGREEMENT WITH TREND TOWARD
PATTERN AMPLIFICATION AS A TROUGH MOVES INTO THE WRN CONUS AND RIDGE
DEVELOPS FROM THE CNTRL ROCIES INTO THE PLAINS. THE NW FLOW PATTERN
INTO THE UPPER GREAT LAKES WILL BRING A SFC HIGH AND COOLER DRIER
AIR INTO UPPER MI MON-TUE WHICH WOULD GIVE WAY TO WARMING BY
WED-THU. CONFIDENCE IN PCPN POTENTIAL BY WED-THU WITH POTENTIAL
FRONTAL SYSTEM AND HEIGHT FALLS IS LOW GIVEN INCREASING MODEL SPREAD
AND RUN TO RUN VARIATION WITH THE STRENGTH OF THE RIDGE. SO
CONSENSUS SLIGHT CHANCE POPS WERE NOT ALTERED.
&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 753 AM EDT FRI AUG 24 2012

LULL IN SHRA/TSRA THROUGH MID MORNING...BUT COULD SEE ANOTHER ROUND
OF SHRA/TSRA DEVELOP BY MID AFTERNOON WITH DAYTIME HEATING AND AS
UPPER DISTURBANCE SLIDES ACROSS UPPER MICHIGAN. BEST CHANCE OF
SHRA/TSRA LATER TODAY WILL BE AT KSAW AS SHARP DRYING WORKING IN
FROM NORTHERN PLAINS WILL RESTRICT DEVELOPMENT OVER WESTERN UPPER
MICHIGAN. SCT-BKN MID CLOUDS POSSIBLE TONIGHT. OVERALL...VFR
CONDITIONS WILL PREVAIL THROUGH TONIGHT.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EDT FRI AUG 24 2012

SOUTH TO SOUTHEAST WINDS REMAIN STRONG TODAY ESPECIALLY OVER EASTERN
SECTIONS WHERE GUSTS MAY REACH 25-30 KTS AT HIGHER PLATFORMS AND
SHIP LEVEL. LOW-LEVEL JET AXIS FADES AWAY TONIGHT...SO WINDS SHOULD
DECREASE TO LESS THAN 20 KTS. WINDS EXPECTED TO REMAIN AT 20 KTS OR
LESS THROUGH THE UPCOMING WEEKEND AND INTO EARLY NEXT WEEK AS
STRONGEST PRESSURE GRADIENT STAYS WELL TO NORTH IN THE VICINITY OF
STRONG SFC LOW OVER HUDSON BAY.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...JLA
LONG TERM...JLB
AVIATION...JLA
MARINE...JLA







AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 525 AM EDT FRI AUG 24 2012

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 523 AM EDT FRI AUG 24 2012

00Z RAOBS AND RUC ANALYSIS INDICATES ZONAL FLOW ALOFT DOWNSTREAM OF
SHARP TROUGH OVER WESTERN CANADA AND ON PERIPHERY OF BROAD RIDGE
OVER CENTRAL CONUS. AT THE SFC...DISJOINTED COMPLEX OF TROUGHS ARE
PRESENT FROM SAKSATCHEWAN INTO NORTH DAKOTA.

HAVE A DOWNRIGHT MESS OF CONVECTION OVER UPR LAKES THIS MORNING
AHEAD OF PAIR OF STRONGER SHORTWAVE TROUGHS MOVING INTO NORTHWEST
ONTARIO AND INTO SOUTHWEST WISCONSIN. H85 WARM ADVECTION IS
SUPPORTING MORE WEST-TO-EAST ORIENTED SHRA/TSRA OVR LK SUPERIOR
WHILE HEIGHT FALLS AND H85-H7 MOISTURE ADVECTION ALONG 2-5KM MUCAPE
RIBBON AND ALONG WEST EDGE OF H85 JET IS SPURRING ON MULTIPLE
CLUSTERS OF MODERATE-HEAVY SHRA/TSRA FROM SOUTHWEST LK SUPERIOR INTO
NORTHWEST WI AND INTO SOUTHWEST WI. ACTIVITY OVR SOUTHWEST WI IS
MORE ORGANIZED WITH SHARPER HEIGHT FALLS OVR THAT AREA DUE TO
SHORTWAVE. ENTIRE AREA IS WITHIN INFLUENCE OF BROAD DIVERGENCE
ALOFT AS H3 JET STREAK SURGES IN FROM THE NORTHERN PLAINS.

CURRENT RADAR TRENDS AND EXPECTED POSITION OF LOW-LEVEL JET THROUGH
MID MORNING SUGGESTS THAT SHRA/TSRA OVER WESTERN LK SUPERIOR WILL
LIFT ACROSS KEWEENAW AND REST OF LK SUPERIOR THIS MORNING. IT APPEARS
THAT CONVECTION OVER SOUTHWEST WISCONSIN WILL NOT MAKE MUCH PUSH
INTO UPR MICHIGAN AS PRIMARY SHORTWAVE STAYS MAINLY OVR WISCONSIN.
LOOKS LIKE MAIN EFFECT OF BOTH AREAS OF CONVECTION WILL BE TO KEEP
SCT-BKN MID CLOUDS IN OVER MOST CWA THIS MORNING...BUT DO EXPECT
SOME HEATING. BETTER HEATING OCCURS EARLY TO MID AFTN AND COULD TIME
OUT WELL WITH ARRIVAL OF SURGE OF H85-H7 MOISTURE FROM THE SOUTHWEST.
THERE IS CURRENTLY A VERY SHARP EDGE TO THE H7 MOISTURE AS SEEN WITH
ABRUPT CLEARING SEEN OVER SOUTHERN MINNESOTA. SREF /WHICH HAS OKAY
HANDLE ON CURRENT CONVECTIVE TRENDS/ BLASTS THIS DRY MID-LEVEL AIR
INTO WEST THIRD BY EARLY AFTN WITH MOISTURE GRADIENT SETTING UP OVR
CENTRAL CWA. DEPENDING ON EXTENT OF HEATING...INSTABILITY COULD
INCREASE WITH ML BASED CAPES OVR 1000 J/KG IN THE CNTRL CWA 18Z-22Z.
TRIGGER WOULD BE SHORTWAVE TROUGH AND SFC-H85 THETA-E ADVECTION AND
MAYBE DEVELOPING LK BREEZES /THOUGH WITH FAIRLY STRONG 950MB INTO
AFTN NOT AS CONFIDENT IN THIS POSSIBLE TRIGGER/. DEEP LAYER SHEAR
ENDS UP AROUND 30 KTS DURING THE AFTN...SO AT LEAST BRIEF
ORGANIZATION/STRONG STORMS SEEMS POSSIBLE GIVEN THE INSTABILITY.
OVERALL...THINK SETUP CONTINUES TO JUSTIFY GOING FCST OF SCT POPS
MAINLY IN THE AFTN...HIGHEST OVER CENTRAL CWA. CONTINUED TO TRIM
POPS OVER WEST...JUST TOO MUCH DRYING TO TRIGGER ANY ADDITIONAL
CONVECTION THERE. BASED ON CURRENT RADAR/SATELLITE TRENDS...THINK
CLEARING IS LIKELY OVR MOST OF CWA THROUGH THE MORNING. SO...WARMER
TEMPS AS NAM INDICATES ARE PREFERRED. BASED ON MIXING TO H85 TEMPS
NEAR +19C...MAX TEMPS MAY TOP OUT WELL INTO THE UPPER 80S. WARM
START TO THE DAY WILL NOT HINDER THIS PROCESS EITHER.

SHORTWAVE TROUGH/MOISTURE ADVECTION CRUISES EAST EARLY THIS EVENING
AND OTHER THAN SOME SMALL CHANCES HAVE PRETTY MUCH ENDED POPS BTWN
00Z-06Z FOR ALL BUT EAST AND SOUTH FRINGES OF CWA. NAM IS QUITE
BULLISH ON POPS FOR OVERNIGHT TONIGHT...MUCH MORE SO THAN OTHER
MODELS. LOOKING AT SOUNDINGS...MOISTURE IS BACK ON THE INCREASE
ALOFT /ROUGHLY ABOVE H7/. LAPSE RATES KIND OF STEEP H7-H5...TOWARD
7C/KM. A LOT OF DRY AIR BLO H7 AND STRONG LIFT LOOKS TO BE LACKING.
MAY SEE A WEAK SHORTWAVE STREAKING OUT AHEAD OF DEEPER WESTERN
CANADA TROUGH WHICH COULD ENHANCE LIFT. KEPT ISOLD MENTION FOR
SHRA/TSRA OVER NORTH TWO-THIRDS OF CWA OUT INTO LK SUPERIOR ALONG
AND NORTH OF H85 FRONT...BUT EVEN THIS POSSIBILITY WILL DIMINISH
LATE IN THE NIGHT AS H7 MOISTURE TRANSPORT WEAKENS AS DOES UVM IN
THE H7-H5 LAYER. SHOULD BE ANOTHER WARM NIGHT /READINGS IN THE 60S/
DUE TO PERSISTENT SOUTH WINDS OUT AHEAD OF SFC LOW DEEPENING OVR
CANADIAN PRAIRIES.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 523 AM EDT FRI AUG 24 2012

SATURDAY...AS THE MID LEVEL LOW OVER SASK LIFTS INTO NORTHERN
MANITOBA RIDGING WILL PREVAIL DOWNSTREAM OVER THE GREAT LAKES. AS A
RESULT...DRY MID LEVELS AND CAPPNIG SHOULD LIMIT ANY PCPN
CHANCES...PER ECMWF/GFS. HOWEVER...SINCE THE REGIONAL GEM AND NAM
CONTINUE TO SUGGEST THAT A WEAK SHORTWAVE TROUGH LIFTING OUT OF THE
UPPER MS VALLEY COULD BRING SOME PCPN INTO THE WEST...SLIGHT CHANCE
WAS MENTIONED IN THE LATE AFTERNOON. WITH PLENTY OF SUNSHINE/MIXING
AND 850 MB TEMPS INTO THE 18C-20C RANGE...EXPECT MAX READINGS INTO
THE UPPER 80S WITH A FEW 90S POSSIBLE IN SW FLOW DOWNSLOPE LOCATIONS.

SATURDAY NIGHT AND SUNDAY...THE MODELS SUGGEST THAT THE STRONGER
FORCING AND HEIGHT FALLS AHEAD OF THE MID LEVEL LOW WILL REMAIN
NORTH OF UPPER MICHIGAN WHILE A WEAKER SHORTWAVE MOVING OUT OF THE
CNTRL PLAINS AND GREATER INSTABILITY WILL REMAIN TO THE SOUTH.
SO...THE DRIER QPF FROM THE ECMWF/GEM SCENARIO WAS PREFERRED
COMPARED TO THE GFS. NEVERTHELESS...SCT SHRA/TSRA ARE STILL EXPECTED
AS THE SFC TROUGH AND AXIS OF HIGHER MOISTURE MOVE THROUGH THE CWA.
ANY LINGERING PCPN SHOULD EXIT THE CNTRL CWA SUN EVENING AND THE
EAST OVERNIGHT.

MON-THU...THE MODELS WERE IN GENERAL AGREEMENT WITH TREND TOWARD
PATTERN AMPLIFICATION AS A TROUGH MOVES INTO THE WRN CONUS AND RIDGE
DEVELOPS FROM THE CNTRL ROCIES INTO THE PLAINS. THE NW FLOW PATTERN
INTO THE UPPER GREAT LAKES WILL BRING A SFC HIGH AND COOLER DRIER
AIR INTO UPPER MI MON-TUE WHICH WOULD GIVE WAY TO WARMING BY
WED-THU. CONFIDENCE IN PCPN POTENTIAL BY WED-THU WITH POTENTIAL
FRONTAL SYSTEM AND HEIGHT FALLS IS LOW GIVEN INCREASING MODEL SPREAD
AND RUN TO RUN VARIATION WITH THE STRENGTH OF THE RIDGE. SO
CONSENSUS SLIGHT CHANCE POPS WERE NOT ALTERED.
&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 140 AM EDT FRI AUG 24 2012

VFR CONDITIONS ARE EXPECTED AT ALL SITES THROUGHOUT THE PERIOD. MORE
SHOWERS AND THUNDERSTORMS WILL MOVE BACK IN OVERNIGHT OVER KIWD AND
KCMX AND PUT SOME THUNDER INTO THE KCMX AND KIWD EARLY THIS TAF
PERIOD AS THERE ARE THUNDERSTORMS HEADED TOWARDS THAT AREA FROM NW
WISCONSIN. THIS IS ALSO WHERE MOST UNSTABLE AIR WILL BE AND BEST PCPN
CHANCES. FOR KSAW...KEPT SHOWERS MOSTLY WEST AND PUT IN PROB30 GROUP
WHEN TROUGH PASSES IN THE AFTERNOON. A LOW-LEVEL JET WILL CREATE WEAK
LLWS AT ALL SITES OVERNIGHT. PCPN SHOULD BE OUT OF THE AREA BY
MORNING AT ALL SITES EXCEPT FOR SAW WHERE IT WILL LINGER INTO THE MID
AFTERNOON.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EDT FRI AUG 24 2012

SOUTH TO SOUTHEAST WINDS REMAIN STRONG TODAY ESPECIALLY OVER EASTERN
SECTIONS WHERE GUSTS MAY REACH 25-30 KTS AT HIGHER PLATFORMS AND
SHIP LEVEL. LOW-LEVEL JET AXIS FADES AWAY TONIGHT...SO WINDS SHOULD
DECREASE TO LESS THAN 20 KTS. WINDS EXPECTED TO REMAIN AT 20 KTS OR
LESS THROUGH THE UPCOMING WEEKEND AND INTO EARLY NEXT WEEK AS
STRONGEST PRESSURE GRADIENT STAYS WELL TO NORTH IN THE VICINITY OF
STRONG SFC LOW OVER HUDSON BAY.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...JLA
LONG TERM...JLB
AVIATION...07
MARINE...JLA







AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

 703 PM CDT SAT AUG 25 2012

.UPDATED FOR 00Z AVIATION DISCUSSION...

&&

.DISCUSSION...

A DUO OF WEAK SHORTWAVES IS DETECTABLE IN EARLY AFTERNOON RADAR
IMAGERY...ONE ROTATING FROM EAST CENTRAL MN INTO WEST CENTRAL
WISCONSIN...AND THE OTHER OVER NORTHEAST IA. MEANWHILE...THE
PRECIPITATION ASSOCIATED WITH THE NORTHERN STREAM TROUGH OVER
NORTHWEST ONTARIO IS SHIFTING TOWARD LAKE SUPERIOR. THE DYNAMICS
AND 850-700MB MOISTURE TRANSPORT ASSOCIATED WITH THESE FEATURES
WILL CONTINUE SHIFTING EAST OF THE FORECAST AREA DURING THE LATE
AFTERNOON AND EARLY EVENING...WITH ONLY WIDELY SCATTERED SHOWERS
LINGERING OVER WEST CENTRAL WI AFTER DARK. CONCERN THEN SHIFTS TO
CLOUD COVER AND THE POTENTIAL FOR FOG DEVELOPMENT OVERNIGHT.
SURFACE COLD FRONT HAS ENTERED WEST/NORTH CENTRAL MN
TODAY...ALTHOUGH IT WILL WASH OUT PRIOR TO REACHING CENTRAL MN.
WHILE POST-FRONTAL DEWPOINTS ARE IN THE MID TO UPPER 40S...PRE-
FRONTAL DEWPOINTS BETWEEN 65 AND 70 DEGREES ARE COMMON THIS
AFTERNOON ACROSS THE CWFA. THEREFORE...GIVEN THE LIGHT WIND
FIELD...AREAS THAT ARE ABLE TO CLEAR OUT TONIGHT WILL BE
SUSCEPTIBLE TO FOG DEVELOPMENT. THIS APPEARS MOST LIKELY ACROSS
WEST CENTRAL MN. FOR SOUTH CENTRAL MN...SHORT RANGE
MODELS...INCLUDING THE RAP AND THE NAM...INDICATE STRATUS CLOUDS
WILL LIFT OUT OF IOWA OVERNIGHT...SO LOW CEILINGS WILL BE MORE OF
A CONCERN THERE.

ON SUNDAY...A FEW SHOWERS MAY BE LINGERING FROM NEAR EAU CLAIRE TO
LADYSMITH IN THE MORNING. AN OTHERWISE DRY DAY IS EXPECTED...AS THE
AREA REMAINS SANDWICHED BETWEEN THE HUDSON BAY CYCLONE AND THE
AMPLIFYING WESTERN RIDGE. AFTER MORNING FOG AND LINGERING LOW CLOUDS
CLEAR...TEMPERATURES WILL REBOUND INTO THE LOW/MID 80S DURING THE
AFTERNOON UNDER MOSTLY SUNNY SKIES AND LIGHT WEST/SOUTHWEST WINDS.

THE MAIN WEATHER HEADLINE FOR THE UPCOMING WEEK WILL BE VERY WARM
TEMPERATURES...AS THE WESTERN RIDGE EXPANDS INTO THE CENTRAL UNITED
STATE. BY MID WEEK...TEMPERATURES WILL BE AROUND 15 DEGREES ABOVE
NORMAL...WITH HIGHS IN THE UPPER 80S TO LOWER 90S COMMON FROM
TUESDAY THROUGH THURSDAY. STILL CAN/T RULE OUT AN ARBITRARY SHOWER OR
THUNDERSTORM...BUT NO ORGANIZED PRECIPITATION IS ANTICIPATED THROUGH
NEXT WEEK.

THE RIDGE IS EXPECTED TO FLATTEN TOWARD THE END OF THE WORK WEEK
INTO LABOR DAY WEEKEND AS A SHORTWAVE TROUGH TRACKS ACROSS THE
PACIFIC NORTHWEST. THE EVOLUTION OF TC ISAAC WILL COME INTO PLAY
HOWEVER...AND FACTOR INTO HOW MUCH OF A COOL DOWN WE WILL SEE NEXT
WEEKEND. FORECAST CONFIDENCE AFTER FRIDAY IS THEREFORE RATHER LOW.

&&

.AVIATION.../00Z TAF ISSUANCE/
LOW CLOUDS AND FOG ARE THE MAIN CONCERN IN THIS TAF PERIOD.
MVFR/IFR STRATUS IS ENCROACHING UP FROM IOWA...AND THIS WILL BE
OFFSET BY CLEARING SKIES FROM THE WEST. THERE IS PLENTY OF LOW
LEVEL MOISTURE...SO WILL LIKELY SEE FOG DEVELOP AT KSTC AND KRWF
AS THOSE SITES CLEAR OUT OVERNIGHT...WHILE LOW STRATUS SHOULD BE
THE PROMINENT FEATURE AT THE EASTERN SITES. TOMORROW WEST
NORTHWEST WIND WILL BRING IN DRIER AIR WITH CLEARING SKIES AND VFR
CONDITIONS EXPECTED BY AFTERNOON.

KMSP...WILL TAKE THE OPTIMISTIC ROUTE THAT VISBYS AND CEILINGS
WILL NOT DROP BELOW MVFR LEVELS...BUT SOME OF THE GUIDANCE IS
SUGGESTING THAT IFR/LIFR IS POSSIBLE OVERNIGHT. AS OF NOW IT
APPEARS THAT STRATUS WILL BE MAIN CONCERN...WITH FOG AS A
SECONDARY THREAT. EITHER WAY...IT LOOKS LIKE THE WORST OF IT WILL
OCCUR DURING THE 07-12Z TIME RANGE.

/OUTLOOK FOR KMSP/
MONDAY...VFR. WINDS NW AT 10 KTS.
TUESDAY...VFR. WINDS S AT 5KTS.
WEDNESDAY...VFR WITH POSSIBLE MVFR CLOUDS. WINDS SSW AT 10G15KTS.

&&

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

$$

LS/JRB






AREA FORECAST DISCUSSION...UPDATED

NWS ST LOUIS MO

 838 PM CDT SAT AUG 25 2012

.UPDATE...
ISSUED AT 826 PM CDT SAT AUG 25 2012

REASONING PROVIDED BY PREVIOUS SHIFT STILL APPLIES. MAINLY
AFTERNOON DIURNALLY DRIVEN SHOWERS AND ISOLATED THUNDERSTORMS HAVE
DECREASED IN AREAL COVERAGE EARLY THIS EVENING. STILL BELIEVE THAT
AREA OF SHRA AND ISOLATED THUNDERSTORMS GETTING READY TO ENTER
WESTERN MO WILL CONTINUE TO PUSH EASTWARD TONIGHT WHICH WILL
INCREASE CHANCES OF RAIN AFTER MIDNIGHT. THIS AREA IS MAINLY
DRIVEN BY ASCENT FROM UPPER MIDWEST/CENTRAL PLAINS TROUGH. RAP IS
ALSO SHOWING AN IN INCREASE IN LOW LEVEL MOISTURE CONVERGENCE OVER
MUCH OF THE CWA AFTER MIDNIGHT AS LOW LEVEL JET INCREASES MOISTURE
TRANSPORT INTO THE AREA. THIS IS ALREADY HANDLED WELL BY GOING
FORECAST AND HAVE MADE ONLY MINOR TWEAKS IN TIMING THROUGH EARLY
TOMORROW. GOING POPS STILL LOOK GOOD FOR TOMORROW/TOMORROW NIGHT
AS TROUGH MOVES ACROSS THE CWA.

BRITT

&&

.SHORT TERM...
ISSUED AT 258 PM CDT SAT AUG 25 2012
(TONIGHT THROUGH MONDAY NIGHT)

BOUNDARY LAYER MOISTURE WILL CONTINUE TO INCREASE AHEAD OF A VERY
SLOW EASTWARD MOVING 500MB SHORTWAVE ACROSS KANSAS/OKLAHOMA THANKS
TO A 20-30KT LOW LEVEL JET. ISOLATED/SCATTERED CONVECTION POSSIBLE
TONIGHT IN THIS WARM ADVECTION REGIME...BUT COVERAGE SHOULD REMAIN
GREATEST WEST WHICH WILL BE CLOSER TO THE SHORTWAVE AND SURFACE
TROF. PWAT VALUES NEAR 2.0 INCHES SHOULD MAKE SOME VERY EFFECTIVE
RAIN PRODUCING SHOWERS/STORMS.

LOOK FOR HEAVIEST PRECIPITATION AXIS TO SLOWLY SHIFT EAST ACROSS THE
AREA ON SUNDAY AND SUNDAY NIGHT AS THE SHORTWAVE AND SURFACE
TROF/WEAK LOW MOVE ACROSS THE CWA. SUNDAY HIGH TEMPERATURES WILL
DEPEND ON CLOUD AND PRECIPITATION COVERAGE. THINKING THERE SHOULD BE
A GRADIENT FROM NORTHWEST(BELOW AVERAGE) TO SOUTHEAST(ABOVE
AVERAGE).

THUNDERSTORM CHANCES WILL SHIFT INTO THE SOUTHERN HALF OF THE CWA ON
MONDAY WITH THE SURFACE TROF/FRONT SETTLING SOUTHWARD. THE CHANCE OF
RAIN WILL END FOR THE ENTIRE AREA MON NGT AS HIGH PRESSURE BUILDS
SOUTH FROM THE UPPER MIDWEST.

CVKING

&&

.LONG TERM...
ISSUED AT 258 PM CDT SAT AUG 25 2012
(TUESDAY THROUGH SATURDAY)

AN UPPER LEVEL RIDGE WILL BUILD OVER THE REGION NEXT WEEK...WITH
A RETURN OF ABOVE NORMAL TEMPERATURES TO END THE MONTH OF AUGUST.
HAVE MY DOUBTS ON HOW MUCH IMPACT ISAAC WILL HAVE ON THE
FORECAST...EVEN WITH THE LATEST GFS RUN BRINGING THE REMNANTS
OVERHEAD BY THE END OF THE WORK WEEK AND NEXT WEEKEND. THIS TRACK
IS CLIMATOLOGICALLY NOT FAVORED...AS RECURVE OF THESE TROPICAL
SYSTEMS NORMALLY FAVORS A LANDFALL OF WESTERN LOUISIANA OR TEXAS
FOR OUR CWA TO SEE ANY IMPACT. HAVE FOLLOWED HPC GUIDANCE PRETTY
CLOSELY IN THE EXTENDED WHICH FAVORS A TRACK MUCH FURTHER EAST
AFTER LANDFALL SIMILAR TO THE 12Z ECWMF.

CVKING

&&

.AVIATION...
ISSUED AT 644 PM CDT SAT AUG 25 2012

WEEKLY DEFINED UPPER LEVEL LOW OVER NORTH CENTRAL KANSAS WILL
GRADUALLY GET CAUGHT INTO THE NORTHERN SHORT WAVE AS IT DIVES INTO
THE OHIO VALLEY MONDAY. THUS EXPECT SUNDAY TO BE CLOSE TO A REAT
OF SATURDAY WITH MAINLY DIURNAL SHOWERS DEVELOPING FROM LATE
MORINNG INTO THE AFTERNOON. BETTER CHANCE OF MORE WIDESPREAD RAIN
AND MVFR CEILINGS SUNDAY NIGHT INTO MONDAY.

SPECIFICS FOR KSTL...HAVE GONE MORE OPTIMISTIC THAT GUIDANCE AND
LEFT VFR CONDITIONS THROUGH THE PERIOD. WITH A LITTLE SLOWER
MOVEMENT OF THE UPPER LOW...SUNDAY LOOKS TO BE PRETTY MUCH A
REPEAT OF TODAY. SHOWERS DEVELOPING PRIMARILY LATE MORNING INTO
THE AFTERNOON...ALTHOUGHT THE COVERAGE MAY BE HIGHER. EXPECT MOST
SHOWERS TO BE DIURNALLY DRIVEN WITH A DECREASE AFTER SUNSET
SUNDAY. AT THE SYSTEM MOVE EAST AND GETS CAUGHT UP IN THE WAVE
MOVING THROGH THE UPPER MIDWEST...MVFR CONDITIONS MAY DEVELOP
SUNDAY NIGHT INTO MONDAY.

JPK

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







AREA FORECAST DISCUSSION

NWS NORTH PLATTE NE

 1250 PM CDT FRI AUG 24 2012

.AVIATION...

    CONDITIONAL CLIMATOLOLOGY INDICATED THAT STRATUS IN SOUTHWEST
NEBRASKA WILL LIFT AROUND 19Z...AND CEILINGS WILL BE ABOVE THE
MARGINAL VISUAL THRESHOLDS. INSTRUMENT CEILINGS ARE EXPECTED TO
DEVELOP AGAIN OVER NORTH CENTRAL THROUGH SOUTHWEST NEBRASKA AFTER
07Z. THE CEILINGS WILL AGAIN LIFT TO MARGINAL THRESHOLDS IN BBW AND
LBF AFTER 15Z. LATER IN THE MORNING...A FRONT WILL PUSH THE LOW
CEILINGS OUT OF THAT AREA BY 18Z.
&&

.PREV DISCUSSION... /ISSUED 349 AM CDT FRI AUG 24 2012/

SHORT TERM...TODAY THROUGH SUNDAY NIGHT

PRIMARY CONCERNS THROUGH THE FIRST FEW DAYS OF THE FORECAST DEAL
WITH TEMPERATURES...CLOUD COVER...AND RAIN CHANCES THROUGH
SATURDAY.

ONGOING STORM COMPLEX BRINGING MUCH NEEDED RAINFALL ACROSS KANSAS
THIS MORNING...SPC MESOANALYSIS SHOWED STRONG MOISTURE ADVECTION
INTO THE STORMS...WHICH WAS ECHOED BY PROFILER DATA WITH 850MB
WINDS OF 35 TO 45KTS INTO THE SYSTEM. ANALYSIS ALSO SHOWED A
STRONG PRECIPITABLE WATER GRADIENT WITH 1.50 TO 2.00 INCHES ACROSS
KANSAS INTO EASTERN NEBRASKA...WHILE THE NORTHERN NEBRASKA
PANHANDLE WAS OBSERVING VALUES LESS THAN THREE QUARTERS OF AN
INCH. ALTHOUGH GOOD RAINFALL WAS OCCURRING OVER KANSAS...THE LOCAL
AREA STAYED DRY OVERNIGHT. THE AREA DID SEE SOME RAIN
YESTERDAY...HOWEVER AMOUNTS WERE LIGHT WITH KLBF BEING THE
WINNER OF THE DAY WITH 0.13 INCHES. THERE IS LIKELY A FEW
LOCATIONS OVER FRONTIER COUNTY THAT MAY HAVE GOTTEN A BIT MORE
RAINFALL DUE TO SOME LATE EVENING THUNDERSTORMS...HOWEVER NO
REPORTED AMOUNTS HAVE BEEN RECEIVED YET.

LOOKING AT WATER VAPOR IMAGERY...A STRONG UPPER LEVEL LOW WAS
SITUATED OVER THE FOUR CORNERS WITH A GOOD FLUX OF MOISTURE
STREAMING NORTHWARD AHEAD OF THIS SYSTEM. THIS HAS BEEN SEEN IN
THE INCREASE OF PRECIPITABLE WATER VALUES AS WAS MENTIONED ABOVE.
ALSO OF NOTE IN THE LARGE SCALE IS A SHORTWAVE TROUGH OVER THE
PACIFIC NORTHWEST...AS WELL AS TROPICAL STORM ISAAC IN THE
CARIBBEAN. CLOSER TO HOME...LOW PRESSURE WAS ANALYZED OVER
SOUTHEAST COLORADO...WITH A SECOND LOW CENTERED OVER EASTERN
MONTANA. SOUTHERLY WINDS WERE BRINGING MOISTURE IN FROM THE
SOUTH...HOWEVER A TIGHT MOISTURE GRADIENT EXISTED WITH DEWPOINTS
RANGING FROM THE 30S IN SOUTHWEST SOUTH DAKOTA TO THE MID AND UPPER
60S FROM SOUTHWEST INTO CENTRAL NEBRASKA.

FOR TODAY...CLOUD COVER WILL HAVE A LARGE IMPACT ON TEMPERATURES.
THERE IS CONSIDERABLE DIFFERENCES IN THE LOW LEVEL MOISTURE FIELDS
FOR THIS MORNING...WITH THE NAM BEING QUITE A BIT DRIER THAN THE
RAP/GFS SOLUTIONS. THE 11-3.9 IR AT 08Z WAS SHOWING THE
FOG/STRATUS EXPANDING QUITE A BIT SO WILL EDGE ON A MORE CLOUDY
FORECAST FOR TODAY. WITH THE MODELS NOT HANDLING THIS WELL HAVE
LOW CONFIDENCE ON HOW FAST THIS MOISTURE WILL SCOUR OUT TODAY.
EARLIER RAP RUNS HAD KEPT THE LOW CLOUDS IN THROUGH MUCH OF THE
DAY...HOWEVER LATEST /24.06Z RUN/ STARTS TO BREAK THINGS OUT
AROUND 18Z. NAM WOULD ALSO HAVE CLOUDS OUT BY 18Z. WITH NO REAL
FOCUS FOR MOISTURE CONVERGENCE THROUGH THE DAY BELIEVE THE LOW CLOUDS
WILL EVENTUALLY DISSIPATE. MAY START TO SEE SOME MID/HIGH LEVEL
CLOUDS MOVING IN THOUGH AT THIS POINT AS BOTH THE UPPER LOW OVER
THE FOUR CORNERS AND THE PACIFIC NORTHWEST SYSTEM MOVE EAST. SO AS
TEMPERATURES SHOULD START TO RECOVER /WITH GOOD WARMING POTENTIAL
IF SEVERAL HOURS OF SUNSHINE ARE REALIZED/ STILL WENT CONSERVATIVE
WITH HIGHS TODAY AND KEPT SOUTHERN AREAS IN THE MID 80S.

SOME MODELS WOULD SUGGEST PRECIPITATION THIS MORNING AND EARLY
AFTERNOON...BUT FROM THE LOOKS OF MOISTURE TRANSPORT
VECTORS...PRECIPITATION SHOULD BE PUSHED TO THE EAST SO KEPT THE
FORECAST THROUGH MID AFTERNOON DRY. BY 25.00Z THE SOUTHERN UPPER
LEVEL SYSTEM WILL BE OVER EASTERN COLORADO...WITH A SURFACE LOW
REMAINING JUST TO ITS EAST. THE LOW LEVEL JET DOES STRENGTHEN
CONSIDERABLY INTO THE EVENING AND OVERNIGHT HOURS...HOWEVER MOST
OF THIS MOISTURE/CONVERGENCE/ENERGY STAYS INTO CENTRAL AND EASTERN
KANSAS AND EASTERN NEBRASKA SO LIMITED RAIN CHANCES TO THE FAR
EASTERN COUNTIES IN THE FORECAST AREA. THIS WAS SUPPORTED BY THE
23.21Z AND 24.03Z SREF RUNS WHICH DID NOT HAVE ANY PROBABILITIES
OF RAINFALL AMOUNTS OVER 0.25 INCH IN THE LOCAL FORECAST AREA.
CONCERNING THE NORTHERN SYSTEM...THE SHORTWAVE WILL BE OVER
SOUTHERN SASKATCHEWAN AT 25.00Z. THIS WILL BRING THE COLD FRONT
INTO THE WESTERN DAKOTAS AND THE NEBRASKA PANHANDLE. KEPT THE
FORECAST DRY OVERNIGHT AS THE FRONT PUSHES EAST...WITH THE
STRONGEST FORCING STAYING WELL TO THE NORTH. THERE IS INDICATIONS
OF SOME MOISTURE CONVERGENCE ALONG THE FRONT OVERNIGHT...SO
WOULDN/T BE SURPRISED TO SEE AN ISOLATED STORM DEVELOP...BUT AGAIN
DIDN/T HAVE THE CONFIDENCE TO ADD CHANCES IN AT THIS POINT.

THE FRONT PUSHES THROUGH THE FORECAST AREA ON SATURDAY...BRINGING
DRIER AND COOLER AIR BEHIND IT. CONVECTION SHOULD CONTINUE
THROUGH THE DAY ALONG THE FRONT. WITH MODELS BEING IN GOOD
AGREEMENT WITH PUSHING THE RAIN EAST OF THE FORECAST AREA...DID
TREND THE FORECAST THAT DIRECTION. DID LEAVE IN SOME SLIGHT
CHANCES IN THE NORTHEASTERN ZONES TO ACCOUNT FOR SLOWER FRONTAL
MOVEMENT OR LINGERING ACTIVITY. DID KEEP TEMPERATURES AHEAD OF THE
FRONT LOWER AS THE FRONT WILL PUSH THROUGH BEFORE AFTERNOON
HEATING SETS IN...AS WELL AS THE THOUGHT THAT THERE MAY AGAIN BE A
BATCH OF STRATUS IN THESE AREAS IN THE MORNING. ALTHOUGH
TEMPERATURES WILL BE COOLER ON SATURDAY...WITH HIGHS IN THE
80S...DEWPOINTS LOOK TO DROP INTO THE 30S BEHIND THE FRONT. THIS
WILL DROP RELATIVE HUMIDITY TO AROUND 20 PERCENT IN THE AFTERNOON.
ALSO EXPECTING BREEZY NORTHERLY WINDS BEHIND THE FRONT. ALTHOUGH
DON/T ANTICIPATE NEEDING HEADLINES FOR FIRE WEATHER...WILL NEED TO
KEEP THIS IN MIND AS FIRE WEATHER CONDITIONS WILL BE NEAR
CRITICAL.

SATURDAY NIGHT THROUGH SUNDAY NIGHT SHOULD BE FAIRLY QUIET AS
UPPER LEVEL RIDGING STARTS TO BUILD IN AS THE SHORTWAVES EXIT TO
THE EAST. SKIES SHOULD CLEAR THROUGH THE PERIOD WITH HIGH PRESSURE
SETTLING IN. COULD SEE TEMPERATURES DROP DOWN INTO THE 50S OVER
MUCH OF THE AREA SATURDAY NIGHT...DUE TO GOOD RADIATIONAL COOLING.

LONG TERM...MONDAY THROUGH THURSDAY

NO BIG CONCERNS TO DEAL WITH THROUGH THIS PORTION OF THE FORECAST.
THE UPPER LEVEL RIDGE BUILDS IN...SO ANOTHER WARMING TREND IS
EXPECTED WITH HIGHS IN THE UPPER 80S AND 90S THROUGH MUCH OF THE
WEEK. NO GOOD CHANCES FOR RAIN EXIST...ALTHOUGH THERE MAY BE
STORMS TOPPING THE RIDGE TO IMPACT NORTHERN NEBRASKA. WITH VERY
LITTLE CONFIDENCE ON WHEN AND WHERE THESE STORMS WILL DEVELOP KEPT
THE FORECAST DRY THROUGHOUT THIS TIME. WITH THE DRY
CONDITIONS...AND WITH A LACK OF MOISTURE BEING BROUGHT
NORTH...WILL EXPECT LARGE TEMPERATURE SWINGS SO ALTHOUGH HIGHS
WILL BE IN THE 90S...STILL LOOKING AT LOWS IN THE 50S AND LOW 60S
MOST NIGHTS.

EYES CONTINUE TO WATCH TROPICAL STORM ISAAC...WHICH IS WELL OUT IN
THE CARIBBEAN CURRENTLY. LONG TERM MODELS COMING INTO MORE
AGREEMENT IN SOLUTIONS...BRINGING IT ONSHORE NEAR MOBILE ALABAMA
THEN PUSHING NORTHWARD INTO THE OHIO RIVER VALLEY BEFORE BEING
CAUGHT UP IN THE FLOW AND SHUNTED EAST. THIS WOULD PROVIDE NO HELP
TO THE LOCAL AREA IN TERMS OF MOISTURE UNFORTUNATELY. THIS IS ALL
TO OCCUR NEXT WEEKEND AND THE NEXT WEEK SO THINGS COULD CERTAINLY
CHANGE BEFORE THEN AND WILL BE WATCHING TO SEE IF THERE MAY BE ANY
IMPACT LOCALLY FROM THIS STORM.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&

$$

SHORT TERM/EXTENDED...WFO LBF
AVIATION...SPRINGER






AREA FORECAST DISCUSSION

NWS NORTH PLATTE NE

 643 AM CDT FRI AUG 24 2012

.AVIATION...

FOR THE KLBF AND KVTN TERMINALS THROUGH 12Z SATURDAY.

FOR THE KLBF TERMINAL...ABUNDANT LOW LEVEL MOISTURE IS EXPECTED OVER
THE NEXT 24 HOURS...WHICH WILL LEAD TO PERIODS OF LOW LEVEL
CLOUDINESS OVER THE NEXT 24 HOURS. PERIODIC MVFR CIGS ARE EXPECTED
THROUGH EARLY AFTERNOON WITH VFR CIGS EXPECTED THROUGH MID EVENING.
WITH COOLING TEMPS AFTER SUNDOWN...LOW LEVEL CLOUDINESS WILL BEGIN
TO WORK BACK INTO SOUTHWESTERN NEBRASKA AFTER 04Z TONIGHT. BASED ON
THE LATEST SREF PROBABILITIES...NOT CONFIDENT ENOUGH YET TO PUT IFR
CIGS IN THE LAST 6 HRS OF THE FCST AND WILL OPT FOR MVFR CIGS ATTM.
AS FOR PRECIPITATION...COVERAGE IS EXPECTED TO BE SCATTERED SOUTH
AND EAST OF THE KLBF TERMINAL...WITH ISOLATED COVERAGE FCST IN THE
KLBF VICINITY. WITH THIS IN MIND...WILL FORGO MENTION OF TSRAS IN
THE 12Z KLBF TAF. WINDS OVER THE NEXT 24 HRS...WILL BE FROM THE
SOUTHEAST OR EAST SOUTHEAST AT UNDER 10 KTS.

FOR THE KVTN TERMINAL...LOW CLOUDINESS...PER SATELLITE
IMAGERY...WILL APPROACH THE KVTN TERMINAL AROUND 12Z THIS MORNING.
SINCE THE TERMINAL WILL BE ON THE NRN PERIPHERY OF THE LOW
CLOUDINESS...WILL HANDLE IT WITH A TEMPO GROUP THROUGH LATE MORNING.
EXPECT SOME SCATTERED TO BROKEN MID LEVEL CLOUDINESS TO DEVELOP
LATER THIS AFTERNOON WITH CIGS RANGING FROM 7000 TO 9000 FT AGL.
SOME LOW CLOUDINESS MAY WORK INTO NORTHERN NEBRASKA OVERNIGHT
TONIGHT IN ASSOC WITH A COOL FRONTAL BOUNDARY. WILL HANDLE THIS WITH
MVFR CIGS ATTM...AS SREF PROBABILITIES ARE LOW FOR SUB 1000 FT CIGS.
WINDS WILL BE FROM THE SOUTH AT 10 KTS THIS MORNING...INCREASING TO
10 TO 20 KTS THIS AFTERNOON...BEFORE DIMINISHING TO AROUND 10 KTS
TONIGHT. A SHIFT IN WIND DIRECTION TO THE NORTH IS EXPECTED TOWARD
DAYBREAK SATURDAY.

&&

.PREV DISCUSSION... /ISSUED 349 AM CDT FRI AUG 24 2012/

SHORT TERM...TODAY THROUGH SUNDAY NIGHT

PRIMARY CONCERNS THROUGH THE FIRST FEW DAYS OF THE FORECAST DEAL
WITH TEMPERATURES...CLOUD COVER...AND RAIN CHANCES THROUGH
SATURDAY.

ONGOING STORM COMPLEX BRINGING MUCH NEEDED RAINFALL ACROSS KANSAS
THIS MORNING...SPC MESOANALYSIS SHOWED STRONG MOISTURE ADVECTION
INTO THE STORMS...WHICH WAS ECHOED BY PROFILER DATA WITH 850MB
WINDS OF 35 TO 45KTS INTO THE SYSTEM. ANALYSIS ALSO SHOWED A
STRONG PRECIPITABLE WATER GRADIENT WITH 1.50 TO 2.00 INCHES ACROSS
KANSAS INTO EASTERN NEBRASKA...WHILE THE NORTHERN NEBRASKA
PANHANDLE WAS OBSERVING VALUES LESS THAN THREE QUARTERS OF AN
INCH. ALTHOUGH GOOD RAINFALL WAS OCCURRING OVER KANSAS...THE LOCAL
AREA STAYED DRY OVERNIGHT. THE AREA DID SEE SOME RAIN
YESTERDAY...HOWEVER AMOUNTS WERE LIGHT WITH KLBF BEING THE
WINNER OF THE DAY WITH 0.13 INCHES. THERE IS LIKELY A FEW
LOCATIONS OVER FRONTIER COUNTY THAT MAY HAVE GOTTEN A BIT MORE
RAINFALL DUE TO SOME LATE EVENING THUNDERSTORMS...HOWEVER NO
REPORTED AMOUNTS HAVE BEEN RECEIVED YET.

LOOKING AT WATER VAPOR IMAGERY...A STRONG UPPER LEVEL LOW WAS
SITUATED OVER THE FOUR CORNERS WITH A GOOD FLUX OF MOISTURE
STREAMING NORTHWARD AHEAD OF THIS SYSTEM. THIS HAS BEEN SEEN IN
THE INCREASE OF PRECIPITABLE WATER VALUES AS WAS MENTIONED ABOVE.
ALSO OF NOTE IN THE LARGE SCALE IS A SHORTWAVE TROUGH OVER THE
PACIFIC NORTHWEST...AS WELL AS TROPICAL STORM ISAAC IN THE
CARIBBEAN. CLOSER TO HOME...LOW PRESSURE WAS ANALYZED OVER
SOUTHEAST COLORADO...WITH A SECOND LOW CENTERED OVER EASTERN
MONTANA. SOUTHERLY WINDS WERE BRINGING MOISTURE IN FROM THE
SOUTH...HOWEVER A TIGHT MOISTURE GRADIENT EXISTED WITH DEWPOINTS
RANGING FROM THE 30S IN SOUTHWEST SOUTH DAKOTA TO THE MID AND UPPER
60S FROM SOUTHWEST INTO CENTRAL NEBRASKA.

FOR TODAY...CLOUD COVER WILL HAVE A LARGE IMPACT ON TEMPERATURES.
THERE IS CONSIDERABLE DIFFERENCES IN THE LOW LEVEL MOISTURE FIELDS
FOR THIS MORNING...WITH THE NAM BEING QUITE A BIT DRIER THAN THE
RAP/GFS SOLUTIONS. THE 11-3.9 IR AT 08Z WAS SHOWING THE
FOG/STRATUS EXPANDING QUITE A BIT SO WILL EDGE ON A MORE CLOUDY
FORECAST FOR TODAY. WITH THE MODELS NOT HANDLING THIS WELL HAVE
LOW CONFIDENCE ON HOW FAST THIS MOISTURE WILL SCOUR OUT TODAY.
EARLIER RAP RUNS HAD KEPT THE LOW CLOUDS IN THROUGH MUCH OF THE
DAY...HOWEVER LATEST /24.06Z RUN/ STARTS TO BREAK THINGS OUT
AROUND 18Z. NAM WOULD ALSO HAVE CLOUDS OUT BY 18Z. WITH NO REAL
FOCUS FOR MOISTURE CONVERGENCE THROUGH THE DAY BELIEVE THE LOW CLOUDS
WILL EVENTUALLY DISSIPATE. MAY START TO SEE SOME MID/HIGH LEVEL
CLOUDS MOVING IN THOUGH AT THIS POINT AS BOTH THE UPPER LOW OVER
THE FOUR CORNERS AND THE PACIFIC NORTHWEST SYSTEM MOVE EAST. SO AS
TEMPERATURES SHOULD START TO RECOVER /WITH GOOD WARMING POTENTIAL
IF SEVERAL HOURS OF SUNSHINE ARE REALIZED/ STILL WENT CONSERVATIVE
WITH HIGHS TODAY AND KEPT SOUTHERN AREAS IN THE MID 80S.

SOME MODELS WOULD SUGGEST PRECIPITATION THIS MORNING AND EARLY
AFTERNOON...BUT FROM THE LOOKS OF MOISTURE TRANSPORT
VECTORS...PRECIPITATION SHOULD BE PUSHED TO THE EAST SO KEPT THE
FORECAST THROUGH MID AFTERNOON DRY. BY 25.00Z THE SOUTHERN UPPER
LEVEL SYSTEM WILL BE OVER EASTERN COLORADO...WITH A SURFACE LOW
REMAINING JUST TO ITS EAST. THE LOW LEVEL JET DOES STRENGTHEN
CONSIDERABLY INTO THE EVENING AND OVERNIGHT HOURS...HOWEVER MOST
OF THIS MOISTURE/CONVERGENCE/ENERGY STAYS INTO CENTRAL AND EASTERN
KANSAS AND EASTERN NEBRASKA SO LIMITED RAIN CHANCES TO THE FAR
EASTERN COUNTIES IN THE FORECAST AREA. THIS WAS SUPPORTED BY THE
23.21Z AND 24.03Z SREF RUNS WHICH DID NOT HAVE ANY PROBABILITIES
OF RAINFALL AMOUNTS OVER 0.25 INCH IN THE LOCAL FORECAST AREA.
CONCERNING THE NORTHERN SYSTEM...THE SHORTWAVE WILL BE OVER
SOUTHERN SASKATCHEWAN AT 25.00Z. THIS WILL BRING THE COLD FRONT
INTO THE WESTERN DAKOTAS AND THE NEBRASKA PANHANDLE. KEPT THE
FORECAST DRY OVERNIGHT AS THE FRONT PUSHES EAST...WITH THE
STRONGEST FORCING STAYING WELL TO THE NORTH. THERE IS INDICATIONS
OF SOME MOISTURE CONVERGENCE ALONG THE FRONT OVERNIGHT...SO
WOULDN/T BE SURPRISED TO SEE AN ISOLATED STORM DEVELOP...BUT AGAIN
DIDN/T HAVE THE CONFIDENCE TO ADD CHANCES IN AT THIS POINT.

THE FRONT PUSHES THROUGH THE FORECAST AREA ON SATURDAY...BRINGING
DRIER AND COOLER AIR BEHIND IT. CONVECTION SHOULD CONTINUE
THROUGH THE DAY ALONG THE FRONT. WITH MODELS BEING IN GOOD
AGREEMENT WITH PUSHING THE RAIN EAST OF THE FORECAST AREA...DID
TREND THE FORECAST THAT DIRECTION. DID LEAVE IN SOME SLIGHT
CHANCES IN THE NORTHEASTERN ZONES TO ACCOUNT FOR SLOWER FRONTAL
MOVEMENT OR LINGERING ACTIVITY. DID KEEP TEMPERATURES AHEAD OF THE
FRONT LOWER AS THE FRONT WILL PUSH THROUGH BEFORE AFTERNOON
HEATING SETS IN...AS WELL AS THE THOUGHT THAT THERE MAY AGAIN BE A
BATCH OF STRATUS IN THESE AREAS IN THE MORNING. ALTHOUGH
TEMPERATURES WILL BE COOLER ON SATURDAY...WITH HIGHS IN THE
80S...DEWPOINTS LOOK TO DROP INTO THE 30S BEHIND THE FRONT. THIS
WILL DROP RELATIVE HUMIDITY TO AROUND 20 PERCENT IN THE AFTERNOON.
ALSO EXPECTING BREEZY NORTHERLY WINDS BEHIND THE FRONT. ALTHOUGH
DON/T ANTICIPATE NEEDING HEADLINES FOR FIRE WEATHER...WILL NEED TO
KEEP THIS IN MIND AS FIRE WEATHER CONDITIONS WILL BE NEAR
CRITICAL.

SATURDAY NIGHT THROUGH SUNDAY NIGHT SHOULD BE FAIRLY QUIET AS
UPPER LEVEL RIDGING STARTS TO BUILD IN AS THE SHORTWAVES EXIT TO
THE EAST. SKIES SHOULD CLEAR THROUGH THE PERIOD WITH HIGH PRESSURE
SETTLING IN. COULD SEE TEMPERATURES DROP DOWN INTO THE 50S OVER
MUCH OF THE AREA SATURDAY NIGHT...DUE TO GOOD RADIATIONAL COOLING.

.LONG TERM...MONDAY THROUGH THURSDAY

NO BIG CONCERNS TO DEAL WITH THROUGH THIS PORTION OF THE FORECAST.
THE UPPER LEVEL RIDGE BUILDS IN...SO ANOTHER WARMING TREND IS
EXPECTED WITH HIGHS IN THE UPPER 80S AND 90S THROUGH MUCH OF THE
WEEK. NO GOOD CHANCES FOR RAIN EXIST...ALTHOUGH THERE MAY BE
STORMS TOPPING THE RIDGE TO IMPACT NORTHERN NEBRASKA. WITH VERY
LITTLE CONFIDENCE ON WHEN AND WHERE THESE STORMS WILL DEVELOP KEPT
THE FORECAST DRY THROUGHOUT THIS TIME. WITH THE DRY
CONDITIONS...AND WITH A LACK OF MOISTURE BEING BROUGHT
NORTH...WILL EXPECT LARGE TEMPERATURE SWINGS SO ALTHOUGH HIGHS
WILL BE IN THE 90S...STILL LOOKING AT LOWS IN THE 50S AND LOW 60S
MOST NIGHTS.

EYES CONTINUE TO WATCH TROPICAL STORM ISAAC...WHICH IS WELL OUT IN
THE CARIBBEAN CURRENTLY. LONG TERM MODELS COMING INTO MORE
AGREEMENT IN SOLUTIONS...BRINGING IT ONSHORE NEAR MOBILE ALABAMA
THEN PUSHING NORTHWARD INTO THE OHIO RIVER VALLEY BEFORE BEING
CAUGHT UP IN THE FLOW AND SHUNTED EAST. THIS WOULD PROVIDE NO HELP
TO THE LOCAL AREA IN TERMS OF MOISTURE UNFORTUNATELY. THIS IS ALL
TO OCCUR NEXT WEEKEND AND THE NEXT WEEK SO THINGS COULD CERTAINLY
CHANGE BEFORE THEN AND WILL BE WATCHING TO SEE IF THERE MAY BE ANY
IMPACT LOCALLY FROM THIS STORM.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT/LONG TERM...BROOKS
AVIATION...CLB













AREA FORECAST DISCUSSION

NWS NORTH PLATTE NE

 349 AM CDT FRI AUG 24 2012

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT

PRIMARY CONCERNS THROUGH THE FIRST FEW DAYS OF THE FORECAST DEAL
WITH TEMPERATURES...CLOUD COVER...AND RAIN CHANCES THROUGH
SATURDAY.

ONGOING STORM COMPLEX BRINGING MUCH NEEDED RAINFALL ACROSS KANSAS
THIS MORNING...SPC MESOANALYSIS SHOWED STRONG MOISTURE ADVECTION
INTO THE STORMS...WHICH WAS ECHOED BY PROFILER DATA WITH 850MB
WINDS OF 35 TO 45KTS INTO THE SYSTEM. ANALYSIS ALSO SHOWED A
STRONG PRECIPITABLE WATER GRADIENT WITH 1.50 TO 2.00 INCHES ACROSS
KANSAS INTO EASTERN NEBRASKA...WHILE THE NORTHERN NEBRASKA
PANHANDLE WAS OBSERVING VALUES LESS THAN THREE QUARTERS OF AN
INCH. ALTHOUGH GOOD RAINFALL WAS OCCURRING OVER KANSAS...THE LOCAL
AREA STAYED DRY OVERNIGHT. THE AREA DID SEE SOME RAIN
YESTERDAY...HOWEVER AMOUNTS WERE LIGHT WITH KLBF BEING THE
WINNER OF THE DAY WITH 0.13 INCHES. THERE IS LIKELY A FEW
LOCATIONS OVER FRONTIER COUNTY THAT MAY HAVE GOTTEN A BIT MORE
RAINFALL DUE TO SOME LATE EVENING THUNDERSTORMS...HOWEVER NO
REPORTED AMOUNTS HAVE BEEN RECEIVED YET.

LOOKING AT WATER VAPOR IMAGERY...A STRONG UPPER LEVEL LOW WAS
SITUATED OVER THE FOUR CORNERS WITH A GOOD FLUX OF MOISTURE
STREAMING NORTHWARD AHEAD OF THIS SYSTEM. THIS HAS BEEN SEEN IN
THE INCREASE OF PRECIPITABLE WATER VALUES AS WAS MENTIONED ABOVE.
ALSO OF NOTE IN THE LARGE SCALE IS A SHORTWAVE TROUGH OVER THE
PACIFIC NORTHWEST...AS WELL AS TROPICAL STORM ISAAC IN THE
CARIBBEAN. CLOSER TO HOME...LOW PRESSURE WAS ANALYZED OVER
SOUTHEAST COLORADO...WITH A SECOND LOW CENTERED OVER EASTERN
MONTANA. SOUTHERLY WINDS WERE BRINGING MOISTURE IN FROM THE
SOUTH...HOWEVER A TIGHT MOISTURE GRADIENT EXISTED WITH DEWPOINTS
RANGING FROM THE 30S IN SOUTHWEST SOUTH DAKOTA TO THE MID AND UPPER
60S FROM SOUTHWEST INTO CENTRAL NEBRASKA.

FOR TODAY...CLOUD COVER WILL HAVE A LARGE IMPACT ON TEMPERATURES.
THERE IS CONSIDERABLE DIFFERENCES IN THE LOW LEVEL MOISTURE FIELDS
FOR THIS MORNING...WITH THE NAM BEING QUITE A BIT DRIER THAN THE
RAP/GFS SOLUTIONS. THE 11-3.9 IR AT 08Z WAS SHOWING THE
FOG/STRATUS EXPANDING QUITE A BIT SO WILL EDGE ON A MORE CLOUDY
FORECAST FOR TODAY. WITH THE MODELS NOT HANDLING THIS WELL HAVE
LOW CONFIDENCE ON HOW FAST THIS MOISTURE WILL SCOUR OUT TODAY.
EARLIER RAP RUNS HAD KEPT THE LOW CLOUDS IN THROUGH MUCH OF THE
DAY...HOWEVER LATEST /24.06Z RUN/ STARTS TO BREAK THINGS OUT
AROUND 18Z. NAM WOULD ALSO HAVE CLOUDS OUT BY 18Z. WITH NO REAL
FOCUS FOR MOISTURE CONVERGENCE THROUGH THE DAY BELIEVE THE LOW CLOUDS
WILL EVENTUALLY DISSIPATE. MAY START TO SEE SOME MID/HIGH LEVEL
CLOUDS MOVING IN THOUGH AT THIS POINT AS BOTH THE UPPER LOW OVER
THE FOUR CORNERS AND THE PACIFIC NORTHWEST SYSTEM MOVE EAST. SO AS
TEMPERATURES SHOULD START TO RECOVER /WITH GOOD WARMING POTENTIAL
IF SEVERAL HOURS OF SUNSHINE ARE REALIZED/ STILL WENT CONSERVATIVE
WITH HIGHS TODAY AND KEPT SOUTHERN AREAS IN THE MID 80S.

SOME MODELS WOULD SUGGEST PRECIPITATION THIS MORNING AND EARLY
AFTERNOON...BUT FROM THE LOOKS OF MOISTURE TRANSPORT
VECTORS...PRECIPITATION SHOULD BE PUSHED TO THE EAST SO KEPT THE
FORECAST THROUGH MID AFTERNOON DRY. BY 25.00Z THE SOUTHERN UPPER
LEVEL SYSTEM WILL BE OVER EASTERN COLORADO...WITH A SURFACE LOW
REMAINING JUST TO ITS EAST. THE LOW LEVEL JET DOES STRENGTHEN
CONSIDERABLY INTO THE EVENING AND OVERNIGHT HOURS...HOWEVER MOST
OF THIS MOISTURE/CONVERGENCE/ENERGY STAYS INTO CENTRAL AND EASTERN
KANSAS AND EASTERN NEBRASKA SO LIMITED RAIN CHANCES TO THE FAR
EASTERN COUNTIES IN THE FORECAST AREA. THIS WAS SUPPORTED BY THE
23.21Z AND 24.03Z SREF RUNS WHICH DID NOT HAVE ANY PROBABILITIES
OF RAINFALL AMOUNTS OVER 0.25 INCH IN THE LOCAL FORECAST AREA.
CONCERNING THE NORTHERN SYSTEM...THE SHORTWAVE WILL BE OVER
SOUTHERN SASKATCHEWAN AT 25.00Z. THIS WILL BRING THE COLD FRONT
INTO THE WESTERN DAKOTAS AND THE NEBRASKA PANHANDLE. KEPT THE
FORECAST DRY OVERNIGHT AS THE FRONT PUSHES EAST...WITH THE
STRONGEST FORCING STAYING WELL TO THE NORTH. THERE IS INDICATIONS
OF SOME MOISTURE CONVERGENCE ALONG THE FRONT OVERNIGHT...SO
WOULDN/T BE SURPRISED TO SEE AN ISOLATED STORM DEVELOP...BUT AGAIN
DIDN/T HAVE THE CONFIDENCE TO ADD CHANCES IN AT THIS POINT.

THE FRONT PUSHES THROUGH THE FORECAST AREA ON SATURDAY...BRINGING
DRIER AND COOLER AIR BEHIND IT. CONVECTION SHOULD CONTINUE
THROUGH THE DAY ALONG THE FRONT. WITH MODELS BEING IN GOOD
AGREEMENT WITH PUSHING THE RAIN EAST OF THE FORECAST AREA...DID
TREND THE FORECAST THAT DIRECTION. DID LEAVE IN SOME SLIGHT
CHANCES IN THE NORTHEASTERN ZONES TO ACCOUNT FOR SLOWER FRONTAL
MOVEMENT OR LINGERING ACTIVITY. DID KEEP TEMPERATURES AHEAD OF THE
FRONT LOWER AS THE FRONT WILL PUSH THROUGH BEFORE AFTERNOON
HEATING SETS IN...AS WELL AS THE THOUGHT THAT THERE MAY AGAIN BE A
BATCH OF STRATUS IN THESE AREAS IN THE MORNING. ALTHOUGH
TEMPERATURES WILL BE COOLER ON SATURDAY...WITH HIGHS IN THE
80S...DEWPOINTS LOOK TO DROP INTO THE 30S BEHIND THE FRONT. THIS
WILL DROP RELATIVE HUMIDITY TO AROUND 20 PERCENT IN THE AFTERNOON.
ALSO EXPECTING BREEZY NORTHERLY WINDS BEHIND THE FRONT. ALTHOUGH
DON/T ANTICIPATE NEEDING HEADLINES FOR FIRE WEATHER...WILL NEED TO
KEEP THIS IN MIND AS FIRE WEATHER CONDITIONS WILL BE NEAR
CRITICAL.

SATURDAY NIGHT THROUGH SUNDAY NIGHT SHOULD BE FAIRLY QUIET AS
UPPER LEVEL RIDGING STARTS TO BUILD IN AS THE SHORTWAVES EXIT TO
THE EAST. SKIES SHOULD CLEAR THROUGH THE PERIOD WITH HIGH PRESSURE
SETTLING IN. COULD SEE TEMPERATURES DROP DOWN INTO THE 50S OVER
MUCH OF THE AREA SATURDAY NIGHT...DUE TO GOOD RADIATIONAL COOLING.

.LONG TERM...MONDAY THROUGH THURSDAY

NO BIG CONCERNS TO DEAL WITH THROUGH THIS PORTION OF THE FORECAST.
THE UPPER LEVEL RIDGE BUILDS IN...SO ANOTHER WARMING TREND IS
EXPECTED WITH HIGHS IN THE UPPER 80S AND 90S THROUGH MUCH OF THE
WEEK. NO GOOD CHANCES FOR RAIN EXIST...ALTHOUGH THERE MAY BE
STORMS TOPPING THE RIDGE TO IMPACT NORTHERN NEBRASKA. WITH VERY
LITTLE CONFIDENCE ON WHEN AND WHERE THESE STORMS WILL DEVELOP KEPT
THE FORECAST DRY THROUGHOUT THIS TIME. WITH THE DRY
CONDITIONS...AND WITH A LACK OF MOISTURE BEING BROUGHT
NORTH...WILL EXPECT LARGE TEMPERATURE SWINGS SO ALTHOUGH HIGHS
WILL BE IN THE 90S...STILL LOOKING AT LOWS IN THE 50S AND LOW 60S
MOST NIGHTS.

EYES CONTINUE TO WATCH TROPICAL STORM ISAAC...WHICH IS WELL OUT IN
THE CARIBBEAN CURRENTLY. LONG TERM MODELS COMING INTO MORE
AGREEMENT IN SOLUTIONS...BRINGING IT ONSHORE NEAR MOBILE ALABAMA
THEN PUSHING NORTHWARD INTO THE OHIO RIVER VALLEY BEFORE BEING
CAUGHT UP IN THE FLOW AND SHUNTED EAST. THIS WOULD PROVIDE NO HELP
TO THE LOCAL AREA IN TERMS OF MOISTURE UNFORTUNATELY. THIS IS ALL
TO OCCUR NEXT WEEKEND AND THE NEXT WEEK SO THINGS COULD CERTAINLY
CHANGE BEFORE THEN AND WILL BE WATCHING TO SEE IF THERE MAY BE ANY
IMPACT LOCALLY FROM THIS STORM.

&&

.AVIATION...

FOR THE KLBF AND KVTN TERMINALS THROUGH 12Z SATURDAY.

FOR THE KLBF TERMINAL...ABUNDANT LOW LEVEL MOISTURE IS EXPECTED OVER
THE NEXT 24 HOURS...WHICH WILL LEAD TO IFR CIGS THROUGH LATE MORNING
ACROSS SOUTHWESTERN NEBRASKA. PERIODIC MVFR CIGS ARE EXPECTED
THROUGH EARLY AFTERNOON WITH VFR CIGS EXPECTED THROUGH MID EVENING.
WITH COOLING TEMPS AFTER SUNDOWN...LOW LEVEL CLOUDINESS WILL BEGIN
TO WORK BACK INTO SOUTHWESTERN NEBRASKA AFTER 06Z TONIGHT. BASED ON
THE LATEST SREF PROBABILITIES...NOT CONFIDENT ENOUGH YET TO PUT IFR
CIGS IN THE LAST 6 HRS OF THE FCST AND WILL OPT FOR MVFR CIGS ATTM.
AS FOR PRECIPITATION...COVERAGE IS EXPECTED TO BE SCATTERED SOUTH
AND EAST OF THE KLBF TERMINAL...WITH ISOLATED COVERAGE FCST IN THE
KLBF VICINITY. WITH THIS IN MIND...WILL FORGO MENTION OF TSRAS IN
THE 12Z KLBF TAF. WINDS OVER THE NEXT 24 HRS...WILL BE FROM THE
SOUTHEAST OR EAST SOUTHEAST AT UNDER 10 KTS.

FOR THE KVTN TERMINAL...LOW CLOUDINESS IS EXPECTED TO REMAIN SOUTH
OF THE KVTN TERMINAL THIS MORNING. EXPECT SOME SCATTERED TO BROKEN
MID LEVEL CLOUDINESS TO DEVELOP LATER THIS AFTERNOON WITH CIGS
RANGING FROM 7000 TO 9000 FT AGL. WINDS WILL BE FROM THE SOUTH AT 10
KTS THIS MORNING...INCREASING TO 10 TO 20 KTS THIS
AFTERNOON...BEFORE DIMINISHING TO AROUND 10 KTS TONIGHT.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&

$$

SHORT/LONG TERM...BROOKS
AVIATION...CLB










AREA FORECAST DISCUSSION

NWS ALBUQUERQUE NM

 1153 AM MDT FRI AUG 24 2012

.AVIATION...
18Z TAF CYCLE
ANOTHER ACTIVE SHOWER AND STORM DAY ALTHOUGH THE FOOTPRINT OF MVFR
CONDITIONS ASSOCIATED WITH THE STRONGER STORMS SHOULD BE A BIT
LESS. SANTA FE CURRENTLY HAS SH/TS AROUND THE GREATER AREA SO WENT
BULLISH FOR THAT LOCATION IN THE TEMPO GROUP. ALSO HAVE TEMPO/S IN
FOR FMN...GUP AND ABQ AS THE UPPER LOW PIVOTS EASTWARD OVER
SOUTHERN COLORADO AND NORTHERN NEW MEXICO. GOING WITH VCSH AT LVS
AND WILL WATCH THE SHOWER TRENDS AT THAT LOCATION. NORTHERLY WIND
SHIFT EXPECTED ACROSS THE EASTERN PLAINS TONIGHT BUT NOT LOOKING
AT A LOT OF WIND SPEED BEHIND IT.

50

&&

.PREV DISCUSSION...603 AM MDT FRI AUG 24 2012...
.AVIATION...
UPPER LEVEL LOW TO TRACK ACROSS SOUTHERN COLORADO TODAY...
SUPPORTING A WEST TO EAST MOIST FLOW ACROSS NORTHERN AND WESTERN
ZONES. SOME PATCHY LOW CLOUDS WILL DEVELOP EAST OF THE CENTRAL
MOUNTAINS THIS MORNING...GENERALLY FROM KCQC SOUTH TO NEAR
KSRR. MID AND HIGH LEVEL CLOUDS ALREADY IN PLACE WILL GIVE WAY TO
ISOLATED TO SCATTERED THUNDERSTORMS AND SHOWERS MAINLY OVER THE
HIGHER TERRAIN...WITH THE NORTH CENTRAL MOUNTAINS POTENTIALLY
SEEING MORE ACTIVITY...MAINLY FROM 17Z THROUGH 03Z. THUNDERSTORMS
WILL RESULT IN MFVR CIGS AND VISIBILITIES IN RAIN OR HEAVY RAIN AT
TIMES AS WELL AS SOME MOUNTAIN TOP OBSCURATIONS. MOSTLY MID LEVEL
CLOUDS TO PERSIST AFTER 03Z THROUGH REMAINDER OF PERIOD.

05

.PREV DISCUSSION...300 AM MDT FRI AUG 24 2012...
UPPER LOW CIRCULATION NEAR KFMN EARLY THIS MORNING. RUC OPENS IT UP
BY MIDDAY WHILE FORECAST POSITION WILL BE OVER NRN MTS. GFS SEEMS TO
MOVE THE TROUGH A LITTLE FASTER THAN 24 HOURS AGO WHILE NAM
INDICATES SOME HANG BACK ENERGY WHICH RETARDS EASTWARD PROGRESS AND
THEREFORE THE TROUGHS EXIT UNTIL LATE SATURDAY AFTERNOON.
NONETHELESS...MOISTURE WILL REMAIN IN PLACE TODAY AND TONIGHT
ESPECIALLY AOB H5 WHILE MODELS AND SATELLITE IMAGERY INDICATE DRYING
IN THE UPPER LEVELS OF THE ATMOSPHERE.  UPSLOPE WINDS SHOULD FAVOR
CONVECTION OVER THE WESTERN/NORTHERN MOUNTAINS TODAY AND WITH WIND
SHIFT IN THE NORTHEAST...THE FOCUS FOR RAIN MAY LIKELY SHIFT INTO
THAT REGION LATER THIS AFTERNOON/EVENING WITH THE UPPER TROUGH
NEARING. TEMPERATURES TODAY STILL A BIT ON THE LOWER SIDE OF AVERAGE
CENTRAL AND WEST...BUT A LITTLE ABOVE IN THE EAST.

SATURDAY WILL BE A TRANSITION DAY AS THE TROUGH EXITS AND AN
EASTERLY LOW LEVEL GRADIENT SETS UP OVER EASTERN NEW MEXICO. THERE
MAY BE SOME POTENTIAL FOR AN EAST WIND INTO THE RGV SATURDAY
NIGHT...BUT THIS APPEARS MORE LIKELY SUNDAY/SUNDAY NIGHT AS THE
UPPER HIGH CENTER SETS UP SHOP OVER NRN NM/SRN CO. WHILE LOW LEVEL
MOISTURE MAY START TO DRY/MIX OUT IN THE FAR NORTHWEST...THE
BOUNDARY LAYER WINDS SHOULD KEEP DEWPOINTS FROM CRATERING IN THE
EAST. TEMPERATURE WISE...MOST AREAS SHOULD BE A FEW DEGREES WARMER
THAN AVERAGE DURING THE DAY BY MONDAY...WHILE MINS GENERALLY STAY
ABOVE NORMAL FOR THE NEXT SEVERAL DAYS.

BY MID TO LATE NEXT WEEK...FORECAST MODELS CONTINUE TO HAVE TROUBLE
RESOLVING THE STRENGTH OF THE UPPER HIGH AND THE LOCATION AND
STRENGTH OF THE WESTERLIES OVER THE NORTHERN/CENTRAL TIER OF THE
WESTERN U.S. CONFIDENCE NOT ALL THAT GREAT IN ONE SCENARIO VS
ANOTHER SO GENERIC AFTERNOON/EVENING SHOWERS AND STORMS FAVORING THE
HIGHER TERRAIN SEEMS BEST FOR NOW.

.FIRE WEATHER...
WEAK UPPER LEVEL DISTURBANCE IS CURRENTLY CENTERED NEAR THE FOUR
CORNERS WITH MID AND UPPER LEVEL DRY SLOT WORKING INTO CENTRAL NEW
MEXICO. SURFACE DEWPOINTS DECREASING AS WELL ESPECIALLY WEST AND
CENTRAL ZONES. THE UPPER WAVE WILL MOVE TO THE EAST DURING THE DAY
WITH WETTING RAIN FAVORING THE WESTERN AND NORTHERN ZONES WITH
BREEZY WEST WINDS DEVELOPING THIS AFTERNOON ACROSS THE EAST CENTRAL
PLAINS. TEMPS WARM A BIT MOST ZONES WITH SUBSTANTIAL DECREASES IN
AFTERNOON RH VALUES.

HIGH PRESSURE BUILDS IN THE WAKE OF THE UPPER LEVEL DISTURBANCE WITH
A RIDGE AXIS NEAR THE FOUR CORNERS BY MID DAY SATURDAY SUPPORTING
ADDITIONAL WARMING AND DRYING ACROSS WESTERN AND NORTHCENTRAL ZONES.
SUFFICIENT MOISTURE PERSISTS AT THE SURFACE TO SUPPORT SCATTERED
THUNDERSTORMS OVER THE HIGHER TERRAIN WITH ISOLATED COVERAGE
ELSEWHERE. A BACK DOOR FRONT WILL PUSH INTO THE NORTHEAST LATE ON
SATURDAY AND THROUGH THE EAST PLAINS ON SUNDAY AS THE UPPER HIGH
CENTERS OVER NEW MEXICO. MODERATE GAP WINDS WERE ADDED TO THE GRIDS
FOR SATURDAY NIGHT...AND DEPENDING ON THE STRENGTH OF THE EAST WINDS
SURFACE MOISTURE INCREASES COULD MAKE IT TO THE CONTINENTAL DIVIDE.
WETTING RAINS ON SUNDAY LOOK TO FAVOR THE CENTRAL HIGH TERRAIN AND
ADJACENT EAST SLOPES WITH AN UPTICK IN COVERAGE OVER THE WESTERN
TERRAIN.

MODELS GENERALLY AGREE ON BUILDING THE UPPER HIGH EARLY IN THE WORK
WEEK WITH POSSIBLY A SLIGHT SHIFT TO THE EAST. A MONSOON PLUME WORKS
AROUND THE WESTERN EDGE OF THE HIGH...BUT THE FOCUS REMAINS OVER
MEXICO. THE EASTERN PLAINS LOOK TO BE DRIER WITH PRECIPITATION
SHIFTING TO THE WEST. THE RIDGE LOOKS TO WEAKER LATER IN THE WEEK
WITH A GENERAL DECREASE IN RELATIVE HUMIDITIES AND WETTING RAIN MOST
LOCATIONS.

&&

.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$








AREA FORECAST DISCUSSION...UPDATED

NWS ALBUQUERQUE NM

 603 AM MDT FRI AUG 24 2012

.AVIATION...
UPPER LEVEL LOW TO TRACK ACROSS SOUTHERN COLORADO TODAY...
SUPPORTING A WEST TO EAST MOIST FLOW ACROSS NORTHERN AND WESTERN
ZONES. SOME PATCHY LOW CLOUDS WILL DEVELOP EAST OF THE CENTRAL
MOUNTAINS THIS MORNING...GENERALLY FROM KCQC SOUTH TO NEAR
KSRR. MID AND HIGH LEVEL CLOUDS ALREADY IN PLACE WILL GIVE WAY TO
ISOLATED TO SCATTERED THUNDERSTORMS AND SHOWERS MAINLY OVER THE
HIGHER TERRAIN...WITH THE NORTH CENTRAL MOUNTAINS POTENTIALLY
SEEING MORE ACTIVITY...MAINLY FROM 17Z THROUGH 03Z. THUNDERSTORMS
WILL RESULT IN MFVR CIGS AND VISIBILITIES IN RAIN OR HEAVY RAIN AT
TIMES AS WELL AS SOME MOUNTAIN TOP OBSCURATIONS. MOSTLY MID LEVEL
CLOUDS TO PERSIST AFTER 03Z THROUGH REMAINDER OF PERIOD.

05

&&

.PREV DISCUSSION...300 AM MDT FRI AUG 24 2012...
UPPER LOW CIRCULATION NEAR KFMN EARLY THIS MORNING. RUC OPENS IT UP
BY MIDDAY WHILE FORECAST POSITION WILL BE OVER NRN MTS. GFS SEEMS TO
MOVE THE TROUGH A LITTLE FASTER THAN 24 HOURS AGO WHILE NAM
INDICATES SOME HANG BACK ENERGY WHICH RETARDS EASTWARD PROGRESS AND
THEREFORE THE TROUGHS EXIT UNTIL LATE SATURDAY AFTERNOON.
NONETHELESS...MOISTURE WILL REMAIN IN PLACE TODAY AND TONIGHT
ESPECIALLY AOB H5 WHILE MODELS AND SATELLITE IMAGERY INDICATE DRYING
IN THE UPPER LEVELS OF THE ATMOSPHERE.  UPSLOPE WINDS SHOULD FAVOR
CONVECTION OVER THE WESTERN/NORTHERN MOUNTAINS TODAY AND WITH WIND
SHIFT IN THE NORTHEAST...THE FOCUS FOR RAIN MAY LIKELY SHIFT INTO
THAT REGION LATER THIS AFTERNOON/EVENING WITH THE UPPER TROUGH
NEARING. TEMPERATURES TODAY STILL A BIT ON THE LOWER SIDE OF AVERAGE
CENTRAL AND WEST...BUT A LITTLE ABOVE IN THE EAST.

SATURDAY WILL BE A TRANSITION DAY AS THE TROUGH EXITS AND AN
EASTERLY LOW LEVEL GRADIENT SETS UP OVER EASTERN NEW MEXICO. THERE
MAY BE SOME POTENTIAL FOR AN EAST WIND INTO THE RGV SATURDAY
NIGHT...BUT THIS APPEARS MORE LIKELY SUNDAY/SUNDAY NIGHT AS THE
UPPER HIGH CENTER SETS UP SHOP OVER NRN NM/SRN CO. WHILE LOW LEVEL
MOISTURE MAY START TO DRY/MIX OUT IN THE FAR NORTHWEST...THE
BOUNDARY LAYER WINDS SHOULD KEEP DEWPOINTS FROM CRATERING IN THE
EAST. TEMPERATURE WISE...MOST AREAS SHOULD BE A FEW DEGREES WARMER
THAN AVERAGE DURING THE DAY BY MONDAY...WHILE MINS GENERALLY STAY
ABOVE NORMAL FOR THE NEXT SEVERAL DAYS.

BY MID TO LATE NEXT WEEK...FORECAST MODELS CONTINUE TO HAVE TROUBLE
RESOLVING THE STRENGTH OF THE UPPER HIGH AND THE LOCATION AND
STRENGTH OF THE WESTERLIES OVER THE NORTHERN/CENTRAL TIER OF THE
WESTERN U.S. CONFIDENCE NOT ALL THAT GREAT IN ONE SCENARIO VS
ANOTHER SO GENERIC AFTERNOON/EVENING SHOWERS AND STORMS FAVORING THE
HIGHER TERRAIN SEEMS BEST FOR NOW.

.FIRE WEATHER...
WEAK UPPER LEVEL DISTURBANCE IS CURRENTLY CENTERED NEAR THE FOUR
CORNERS WITH MID AND UPPER LEVEL DRY SLOT WORKING INTO CENTRAL NEW
MEXICO. SURFACE DEWPOINTS DECREASING AS WELL ESPECIALLY WEST AND
CENTRAL ZONES. THE UPPER WAVE WILL MOVE TO THE EAST DURING THE DAY
WITH WETTING RAIN FAVORING THE WESTERN AND NORTHERN ZONES WITH
BREEZY WEST WINDS DEVELOPING THIS AFTERNOON ACROSS THE EAST CENTRAL
PLAINS. TEMPS WARM A BIT MOST ZONES WITH SUBSTANTIAL DECREASES IN
AFTERNOON RH VALUES.

HIGH PRESSURE BUILDS IN THE WAKE OF THE UPPER LEVEL DISTURBANCE WITH
A RIDGE AXIS NEAR THE FOUR CORNERS BY MID DAY SATURDAY SUPPORTING
ADDITIONAL WARMING AND DRYING ACROSS WESTERN AND NORTHCENTRAL ZONES.
SUFFICIENT MOISTURE PERSISTS AT THE SURFACE TO SUPPORT SCATTERED
THUNDERSTORMS OVER THE HIGHER TERRAIN WITH ISOLATED COVERAGE
ELSEWHERE. A BACK DOOR FRONT WILL PUSH INTO THE NORTHEAST LATE ON
SATURDAY AND THROUGH THE EAST PLAINS ON SUNDAY AS THE UPPER HIGH
CENTERS OVER NEW MEXICO. MODERATE GAP WINDS WERE ADDED TO THE GRIDS
FOR SATURDAY NIGHT...AND DEPENDING ON THE STRENGTH OF THE EAST WINDS
SURFACE MOISTURE INCREASES COULD MAKE IT TO THE CONTINENTAL DIVIDE.
WETTING RAINS ON SUNDAY LOOK TO FAVOR THE CENTRAL HIGH TERRAIN AND
ADJACENT EAST SLOPES WITH AN UPTICK IN COVERAGE OVER THE WESTERN
TERRAIN.

MODELS GENERALLY AGREE ON BUILDING THE UPPER HIGH EARLY IN THE WORK
WEEK WITH POSSIBLY A SLIGHT SHIFT TO THE EAST. A MONSOON PLUME WORKS
AROUND THE WESTERN EDGE OF THE HIGH...BUT THE FOCUS REMAINS OVER
MEXICO. THE EASTERN PLAINS LOOK TO BE DRIER WITH PRECIPITATION
SHIFTING TO THE WEST. THE RIDGE LOOKS TO WEAKER LATER IN THE WEEK
WITH A GENERAL DECREASE IN RELATIVE HUMIDITIES AND WETTING RAIN MOST
LOCATIONS.

&&

.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$







AREA FORECAST DISCUSSION

NWS ALBUQUERQUE NM

 300 AM MDT FRI AUG 24 2012

.DISCUSSION...
UPPER LOW CIRCULATION NEAR KFMN EARLY THIS MORNING. RUC OPENS IT UP
BY MIDDAY WHILE FORECAST POSITION WILL BE OVER NRN MTS. GFS SEEMS TO
MOVE THE TROUGH A LITTLE FASTER THAN 24 HOURS AGO WHILE NAM
INDICATES SOME HANG BACK ENERGY WHICH RETARDS EASTWARD PROGRESS AND
THEREFORE THE TROUGHS EXIT UNTIL LATE SATURDAY AFTERNOON.
NONETHELESS...MOISTURE WILL REMAIN IN PLACE TODAY AND TONIGHT
ESPECIALLY AOB H5 WHILE MODELS AND SATELLITE IMAGERY INDICATE DRYING
IN THE UPPER LEVELS OF THE ATMOSPHERE.  UPSLOPE WINDS SHOULD FAVOR
CONVECTION OVER THE WESTERN/NORTHERN MOUNTAINS TODAY AND WITH WIND
SHIFT IN THE NORTHEAST...THE FOCUS FOR RAIN MAY LIKELY SHIFT INTO
THAT REGION LATER THIS AFTERNOON/EVENING WITH THE UPPER TROUGH
NEARING. TEMPERATURES TODAY STILL A BIT ON THE LOWER SIDE OF AVERAGE
CENTRAL AND WEST...BUT A LITTLE ABOVE IN THE EAST.

SATURDAY WILL BE A TRANSITION DAY AS THE TROUGH EXITS AND AN
EASTERLY LOW LEVEL GRADIENT SETS UP OVER EASTERN NEW MEXICO. THERE
MAY BE SOME POTENTIAL FOR AN EAST WIND INTO THE RGV SATURDAY
NIGHT...BUT THIS APPEARS MORE LIKELY SUNDAY/SUNDAY NIGHT AS THE
UPPER HIGH CENTER SETS UP SHOP OVER NRN NM/SRN CO. WHILE LOW LEVEL
MOISTURE MAY START TO DRY/MIX OUT IN THE FAR NORTHWEST...THE
BOUNDARY LAYER WINDS SHOULD KEEP DEWPOINTS FROM CRATERING IN THE
EAST. TEMPERATURE WISE...MOST AREAS SHOULD BE A FEW DEGREES WARMER
THAN AVERAGE DURING THE DAY BY MONDAY...WHILE MINS GENERALLY STAY
ABOVE NORMAL FOR THE NEXT SEVERAL DAYS.

BY MID TO LATE NEXT WEEK...FORECAST MODELS CONTINUE TO HAVE TROUBLE
RESOLVING THE STRENGTH OF THE UPPER HIGH AND THE LOCATION AND
STRENGTH OF THE WESTERLIES OVER THE NORTHERN/CENTRAL TIER OF THE
WESTERN U.S. CONFIDENCE NOT ALL THAT GREAT IN ONE SCENARIO VS
ANOTHER SO GENERIC AFTERNOON/EVENING SHOWERS AND STORMS FAVORING THE
HIGHER TERRAIN SEEMS BEST FOR NOW.

&&

.FIRE WEATHER...
WEAK UPPER LEVEL DISTURBANCE IS CURRENTLY CENTERED NEAR THE FOUR
CORNERS WITH MID AND UPPER LEVEL DRY SLOT WORKING INTO CENTRAL NEW
MEXICO. SURFACE DEWPOINTS DECREASING AS WELL ESPECIALLY WEST AND
CENTRAL ZONES. THE UPPER WAVE WILL MOVE TO THE EAST DURING THE DAY
WITH WETTING RAIN FAVORING THE WESTERN AND NORTHERN ZONES WITH
BREEZY WEST WINDS DEVELOPING THIS AFTERNOON ACROSS THE EAST CENTRAL
PLAINS. TEMPS WARM A BIT MOST ZONES WITH SUBSTANTIAL DECREASES IN
AFTERNOON RH VALUES.

HIGH PRESSURE BUILDS IN THE WAKE OF THE UPPER LEVEL DISTURBANCE WITH
A RIDGE AXIS NEAR THE FOUR CORNERS BY MID DAY SATURDAY SUPPORTING
ADDITIONAL WARMING AND DRYING ACROSS WESTERN AND NORTHCENTRAL ZONES.
SUFFICIENT MOISTURE PERSISTS AT THE SURFACE TO SUPPORT SCATTERED
THUNDERSTORMS OVER THE HIGHER TERRAIN WITH ISOLATED COVERAGE
ELSEWHERE. A BACK DOOR FRONT WILL PUSH INTO THE NORTHEAST LATE ON
SATURDAY AND THROUGH THE EAST PLAINS ON SUNDAY AS THE UPPER HIGH
CENTERS OVER NEW MEXICO. MODERATE GAP WINDS WERE ADDED TO THE GRIDS
FOR SATURDAY NIGHT...AND DEPENDING ON THE STRENGTH OF THE EAST WINDS
SURFACE MOISTURE INCREASES COULD MAKE IT TO THE CONTINENTAL DIVIDE.
WETTING RAINS ON SUNDAY LOOK TO FAVOR THE CENTRAL HIGH TERRAIN AND
ADJACENT EAST SLOPES WITH AN UPTICK IN COVERAGE OVER THE WESTERN
TERRAIN.

MODELS GENERALLY AGREE ON BUILDING THE UPPER HIGH EARLY IN THE WORK
WEEK WITH POSSIBLY A SLIGHT SHIFT TO THE EAST. A MONSOON PLUME WORKS
AROUND THE WESTERN EDGE OF THE HIGH...BUT THE FOCUS REMAINS OVER
MEXICO. THE EASTERN PLAINS LOOK TO BE DRIER WITH PRECIPITATION
SHIFTING TO THE WEST. THE RIDGE LOOKS TO WEAKER LATER IN THE WEEK
WITH A GENERAL DECREASE IN RELATIVE HUMIDITIES AND WETTING RAIN MOST
LOCATIONS.

&&

.AVIATION...
06Z TAF CYCLE
NOT CARRYING ANY SHOWER AT TERMINALS OVERNIGHT. MIGHT BE A CLOSE
CALL AT SAF AROUND 7Z. GENERALLY VFR CONDITIONS THROUGH 18Z FRIDAY.
COULD GET LOCALIZED FOG/BR WITH LOWER CIGS DUE TO PREVIOUS RAINFALL
10Z TO 14Z AT SOME TERMINALS...NAMELY FMN...GUP...TCC AND ROW...
ALTHOUGH MODELS AND GUIDANCE NOT SHOWING MUCH. SHOWERS AND STORMS TO
REFORM FRIDAY...MOSTLY AFTER 18Z AND NORTH OF INTERSTATE 40. WILL
CARRY VCSH AND/OR VCTS AT FMN...GUP...SAF AND LVS FRIDAY AFTERNOON.
CHJ

&&

&&

.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON......................  82  57  89  60 /  30  30  20  20
DULCE...........................  76  51  82  49 /  40  40  20  20
CUBA............................  74  52  79  52 /  30  30  20  20
GALLUP..........................  77  52  84  56 /  30  30  20  20
EL MORRO........................  72  50  79  52 /  30  30  20  20
GRANTS..........................  76  52  84  54 /  30  30  20  20
QUEMADO.........................  76  52  82  55 /  30  30  20  20
GLENWOOD........................  83  60  86  58 /  20  20  20  20
CHAMA...........................  70  45  75  47 /  40  50  30  20
LOS ALAMOS......................  77  54  81  58 /  40  30  20  30
PECOS...........................  77  54  78  55 /  30  30  40  30
CERRO/QUESTA....................  74  47  76  49 /  40  40  20  30
RED RIVER.......................  66  45  70  44 /  50  50  30  40
ANGEL FIRE......................  69  46  72  42 /  40  50  40  40
TAOS............................  78  50  80  52 /  30  40  20  30
MORA............................  75  51  76  52 /  30  30  40  30
ESPANOLA........................  82  56  86  57 /  20  30  20  30
SANTA FE........................  79  55  84  58 /  30  30  30  30
SANTA FE AIRPORT................  81  56  86  59 /  30  30  20  30
ALBUQUERQUE FOOTHILLS...........  83  61  84  63 /  20  20  20  20
ALBUQUERQUE HEIGHTS.............  83  64  87  66 /  20  20  20  30
ALBUQUERQUE VALLEY..............  84  59  89  63 /  20  20  20  20
ALBUQUERQUE WEST MESA...........  84  59  88  63 /  20  20  20  30
LOS LUNAS.......................  86  62  88  63 /  20  20  20  20
RIO RANCHO......................  83  62  87  65 /  20  20  20  30
SOCORRO.........................  86  65  88  65 /  20  20  20  20
SANDIA PARK/CEDAR CREST.........  80  58  78  56 /  20  20  40  30
TIJERAS.........................  82  61  82  59 /  20  30  30  30
MORIARTY/ESTANCIA...............  81  54  85  56 /  30  30  40  30
CLINES CORNERS..................  80  56  81  57 /  30  20  40  30
GRAN QUIVIRA....................  81  59  83  59 /  30  30  40  30
CARRIZOZO.......................  82  63  83  60 /  20  20  20  30
RUIDOSO.........................  76  60  75  54 /  30  30  40  40
CAPULIN.........................  78  49  81  56 /  40  40  30  40
RATON...........................  83  52  84  56 /  40  40  30  30
SPRINGER........................  85  53  85  56 /  30  40  30  30
LAS VEGAS.......................  81  53  81  54 /  30  30  40  30
CLAYTON.........................  87  62  88  61 /  30  40  40  30
ROY.............................  85  60  85  60 /  30  30  40  40
CONCHAS.........................  92  62  91  65 /  20  30  20  20
SANTA ROSA......................  90  62  89  65 /  20  20  20  20
TUCUMCARI.......................  94  63  91  66 /  20  30  20  20
CLOVIS..........................  91  63  89  66 /  10  20  20  20
PORTALES........................  92  64  89  67 /  10  20  20  20
FORT SUMNER.....................  92  65  91  66 /  10  20  20  20
ROSWELL.........................  95  68  93  69 /  10  20  20  20
PICACHO.........................  88  64  85  62 /  10  20  20  20
ELK.............................  83  63  79  59 /  20  20  40  30

&&

.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
















AREA FORECAST DISCUSSION

NWS WILMINGTON NC

 624 PM EDT FRI AUG 24 2012

.SYNOPSIS...
LOW PRESSURE WILL MOVE SLOWLY UP THE CAROLINA COAST OVERNIGHT.
HIGH PRESSURE WILL BUILD SOUTH THIS WEEKEND...BRINGING SLIGHTLY
DRIER AIR INTO THE REGION. TROPICAL STORM ISAAC IS EXPECTED TO
MOVE INTO THE EASTERN GULF OF MEXICO EARLY NEXT WEEK. REMNANTS
OF ISAAC COULD BRING UNSETTLED WEATHER TO THE CAROLINAS BY THE
MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 340 PM FRIDAY...MID TO UPPER LOW WILL TRACK UP THE SOUTHEAST
COAST THROUGH TONIGHT. THE H5 CIRCULATION REMAINS BROAD WITH
CENTER TIGHTENING A BIT OVERNIGHT WITH CENTER FORECAST OVER NC/VA
BORDER BY SAT MORNING. THE ASSOCIATED SURFACE LOW JUST E-SE OF
CAPE FEAR THIS AFTERNOON WILL MOVE NORTH AND BECOME MORE ELONGATED
AS IT WEAKENS THROUGH TONIGHT. NAM STILL SHOWING BEST ENERGY
ASSOCIATED WITH THIS LOW TO MOVE FROM COASTAL WATERS JUST SOUTH OF
CAPE FEAR DUE NORTH INTO NC THIS AFTERNOON. HRRR MODEL SHOWING
BEST CHC FOR HEAVIER PCP FROM THE TIP OF CAPE FEAR NORTH ALONG THE
NORTH CAROLINA COAST MAINLY FROM NEW HANOVER COUNTY THROUGH PENDER
COUNTY. THE BEST CHC OF HEAVIER PCP WILL OCCUR DURING THIS TIME
BUT BULLSEYE FOR HEAVIEST RAIN IN TSTMS WILL REMAIN OVER THE
WATERS TO THE EAST. THE GREATEST THREAT THROUGH WILL BE POTENTIAL
FOR FLOODING AS STEERING FLOW OVER MOST LAND AREAS WILL REMAIN
VERY WEAK. PCP WATER VALUES WILL REMAIN AROUND 2 INCHES UP THE
CAPE FEAR COAST DROPPING OFF AS YOU MOVE INLAND DOWN LESS THAN AN
INCH IN DRIER AIR AND SUBSIDENCE ON BACK END OF LOW WEST OF LOCAL
CWA...OVER CENTRAL TO WESTERN CAROLINAS. WILL KEEP LOW END POPS
INLAND AS SOME ENERGY ROTATES AROUND THE LOW...BUT OVERALL CLOUDS
AND COOLER NORTHERLY FLOW KEEPING TEMPS JUST AROUND 80 AND OVERALL
MORE STABLE ATMOSPHERE.

MODEL SOUNDINGS AND MOISTURE PROFILES SHOWING DRIER AIR WORKING
ITS WAY IN ON THE BACK EDGE OF LOW THROUGH THE MID TO UPPER
LEVELS TONIGHT AS IT LIFTS OFF TO THE NORTH. THIS WILL HELP PCP
SHUT OFF OVER LOCAL AREA. NAM SHOWS PCP WATER VALUES DROPPING
DOWN LESS THAN 1.5 INCHES BY SAT MORNING. CLOUDS...PCP AND FOG
WILL HELP KEEP TEMPS IN THE MID 60S AND CLOSER TO 70 WHERE GREATER
DEWPOINT AIR WILL HANG ON THE LATEST. MAY SEE STRATUS DEVELOP AS
MOISTURE BECOMES TRAPPED UNDER LOW LEVEL INVERSION...MORE PROBABLE
CLOSER TO THE COAST.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 340 PM FRIDAY...A DRIER PATTERN ANTICIPATED THIS WEEKEND...AS
DRY MID-LEVEL AIR OVERSPREADS THE REGION...AND A SURFACE LOW PULLS
SLUGGISHLY NORTH AND AWAY FROM OUR AREA. WEAK UPPER LOW POSITIONED
JUST NORTH OF OUR AREA SATURDAY AND SUNDAY WILL CONTINUE TO FEED
DRY AIR ALOFT...BUT CONCURRENTLY SHOULD PROMPT PLENTY OF DIURNAL
BUT MOSTLY CAPPED CUMULUS. CONVERGENCE OFFSHORE LATE IN THE PERIOD
MAY BRING COASTAL SHOWERS SUNDAY NIGHT. WHILE A SHOWER CANNOT BE
RULED OUT ON THE SEA BREEZE FRONT THIS WEEKEND...ACTIVITY SHOULD
IN OR BELOW THE ISOLATED CATEGORY.

MAXIMUM TEMPS WITH PARTIAL CLOUDS AND HIGH PRESSURE WEDGED IN FROM
THE NORTH...SHOULD RESULT IN MAINLY MIDDLE AND UPPER 80S BOTH DAYS.
MINIMUM TEMPS WILL DIP BELOW 70 MOST LOCATIONS BY DAYBREAK SAT/SUN
BUT QUITE A BIT MORE MILD AT THE COAST IN ONSHORE WIND DIRECTION.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 340 PM FRIDAY...SENSIBLE WEATHER THROUGH THE EXTENDED WILL
DEPEND ALMOST ENTIRELY ON ISAAC AND HIS POTENTIAL IMPACTS TO THE
REGION. STILL CONSIDERABLE UNCERTAINTY DUE TO TRACK
FORECASTS...WHICH...UNFORTUNATELY...WILL CREATE SIGNIFICANT
DIFFERENCES IN THE WEATHER ACROSS THE ILM CWA.

GFS/CMC ARE IN DECENT AGREEMENT WITH THEIR OVERALL EVOLUTION OF
ISAAC WHEN COMPARED TO THE ECMWF WHICH IS THE OUTLIER OF THE THREE
MODELS. WHILE THE ECMWF SLOWLY BRINGS ISAAC UP THROUGH THE GULF
COAST AND MEANDERS IT NW INTO THE TN VLY THROUGH MIDWEEK BEFORE
DISSIPATING...THE GFS/CMC BRING IT SLIGHTLY FURTHER EAST INTO THE
PANHANDLE OF FLORIDA ON TUESDAY AND THEN MAKE A SHARP
RECURVE...MOVING ISAAC`S REMNANTS BASICALLY OVER THE ILM CWA ON
WEDNESDAY. WILL LEAN TOWARDS THE GFS/CMC CONSENSUS...THE THINKING
THAT THE LARGE RIDGE WHICH FORCES THE ECMWF SOLUTION TO REMAIN WEST
IS OVERDONE. THIS MEANS DEEP S/SE FLOW MON/TUE WHICH SHOULD SUPPORT
ADVECTION SHOWERS...ESPECIALLY NEAR THE COAST...AND THEN A MUCH
WETTER DAY WEDNESDAY AS MID LEVEL THETA-E RIDGE ASSOCIATED WITH
ISAAC AND ITS REMNANTS...MOVES OVERHEAD. BY THURSDAY WE SHOULD BE ON
THE DRY WEST SUBSIDENT SIDE OF THE STORM AND WILL DRY OUT FOR LATE
WEEK. STILL MUCH UNCERTAINTY...BUT WILL RAMP POP UPWARDS THROUGH
WEDNESDAY BEFORE RAPIDLY TAILING OFF ON THURSDAY/FRIDAY.

NOTE THAT CURRENT FORECAST IS AT LEAST SLIGHTLY DIFFERENT THAN
HPC/NHC WHICH IS FAVORING A MUCH MORE WESTERN AND SLOWER
TRACK...ECMWF...FOR ISAAC. IF THE ECMWF TRACK WERE TO
VERIFY...WEDNESDAY WOULD STILL BE THE WETTEST DAY...SO POP TRENDS
WOULD STILL BE CORRECT...BUT OVERALL LESS RAINFALL ALONG WITH SLOWER
DECREASE IN POP WOULD BE NEEDED IN THAT SOLUTION (I.E. BETTER RAIN
CHANCES CONTINUING THROUGH THE END OF THE WEEK). WILL HAVE TO
MONITOR GUIDANCE TRENDS AND MODIFY FURTHER FORECAST UPDATES AS
NEEDED.

TEMPS WILL BE AROUND CLIMO MOST DAYS...WARMING TO ABOVE BY THE END
OF THE WEEK.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 00Z...WET PATTERN FINALLY IS BREAKING AS A FAIRLY STRONG VORT
PULLS NORTHEAST...TAKING THE FRONT WITH IT. THE MODERATE TO HEAVY
PRECIP ALONG THE COAST TODAY WILL LIKELY CONTRIBUTE TO IFR
CONDITIONS AT THE COASTAL TERMINALS SOMETIME AFTER MIDNIGHT. THE
INLAND TERMINALS ARE A BIT MORE UNCERTAIN. THERE IS NOT AS MUCH LOW
LEVEL MOISTURE...BUT RADIATIONAL COOLING CONDITIONS ARE REASONABLY
GOOD...AND THE TMP/DPT SPREAD IS NOT MUCH TO BEGIN WITH. LIKEWISE A
LIGHT NORTHEAST WIND IS FAVORABLE. WILL STICK WITH MVFR AT THIS TIME
BUT WILL MONITOR CLOSELY. SATURDAY...A GREAT DAY TO BE OUTSIDE WITH
MODERATE TEMPERATURES AND A NOTICEABLY DRIER ATMOSPHERE. CONTINUED LIGHT
NORTHEAST FLOW...WITH VFR CONDITIONS EXPECTED BY 15Z...CONTINUING
THROUGH THE END OF THE FORECAST PERIOD.

EXTENDED OUTLOOK...ISOLATED SHRA/TSRA MON. BETTER CHANCE OF SHOWERS
AND STORMS TUESDAY AND WEDNESDAY.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 340 PM FRIDAY...MID TO UPPER LOW MOVE UP INTO NORTH CAROLINA
WITH CENTER REACHING THE NC/VA BORDER BY MORNING. AT THE SAME TIME
AN ASSOCIATED AREA OF LOW PRESSURE WILL TRACK SLOWLY UP THROUGH THE
LOCAL COASTAL WATERS REACHING TOWARD HATTERAS AFTER MIDNIGHT.
THIS WILL HELP TO PRODUCE MORE WIDESPREAD PRECIPITATION IN
SHWRS/TSTMS THROUGH THIS EVENING...WINDING DOWN FROM S TO N TONIGHT.

SFC WINDS 10 TO 15 KTS WILL DIMINISH A BIT OVERNIGHT AS THEY BACK
TOWARD THE NW. THIS OFF SHORE FLOW WILL ACT TO LOWER SEAS BUT A
LONGER PERIOD E-SE SWELL UP TO 16 SECONDS WILL COUNTERACT THIS OFF
SHORE FLOW AND WILL PRODUCE A SLIGHT INCREASE IN OVERALL SEAS
OVERNIGHT. SEAS WILL BUILD TO 3 TO 4 FT MAINLY ACROSS THE OUTER
WATERS. EXPECT ROUGHER SEAS WITH HIGHER WINDS AND SEAS IN TSTMS
THROUGH THIS EVENING AND ALSO REDUCED VSBYS DUE TO HEAVY RAIN. RADAR
CONTINUED TO SHOW THE POSSIBILITY OF WATERSPOUTS IN STORMS OVER THE
OUTER COASTAL WATERS THIS AFTERNOON.



SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 340 PM FRIDAY...OUTSIDE OF TSTMS WINDS WILL REMAIN MANAGEABLE
SATURDAY AND SUNDAY...AS A SURFACE LOW OVER THE WATERS MOVES
SLOWLY NORTH OF THE AREA. WINDS WILL VEER EAST SUNDAY AS HIGH
PRESSURE CONSOLIDATES OVER NEW ENGLAND. THE COMBINATION OF WIND-
WAVES AND SWELL WAVES WILL KEEP SEAS MAINLY 3-4 FEET THIS WEEKEND
AND UP TO 5 FEET AT TIMES WELL OFFSHORE. NUMEROUS SHOWERS AND
TSTMS WILL BECOME SCATTERED TO ISOLATED THIS WEEKEND...AS THE SFC
LOW PULLS NORTH OF SURF CITY BY DAYBREAK SATURDAY...AND DRY AIR
ALOFT HELPS TO SQUELCH STORM DEVELOPMENT.


LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 340 PM FRIDAY...QUITE A BIT OF UNCERTAINTY THROUGH THE
EXTENDED AS WIND/WAVE CONDITIONS COULD VARY CONSIDERABLY DEPENDING
ON WHAT HAPPENS WITH TS ISAAC. ANTICIPATE E/SE WINDS MON THROUGH TUE
AS ISAAC MOVES ALONG THE WEST COAST OF FLORIDA AND INTO THE GULF
COAST REGION. THE CONTINUED E/SE WINDS AROUND 10 KTS...UP TO 15 KTS
ACROSS THE SOUTHERN WATERS...WILL GENERATE 2-4 FT SOUTHERLY WIND
WAVES. THESE WIND WAVES WILL COMBINE WITH WHAT SHOULD BE INCREASING
S/SE SWELL OF 4-5FT/9SEC DUE TO TROPICAL SYSTEMS ISAAC AND JOYCE.
GUIDANCE IS NOT VERY ROBUST IN DEVELOPING ANY SIGNIFICANT VERY LONG
PERIOD SWELL...BUT NEVERTHELESS...3-5 FT SEAS ARE EXPECTED THROUGH
TUESDAY...WITH 6 FOOTERS POSSIBLE ACROSS THE SOUTHERN WATERS. SEAS
COULD BUILD MUCH HIGHER WEDNESDAY...ESPECIALLY IF GFS/CMC ARE
CORRECT...DUE TO INCREASING SOUTHERLY WINDS...AND SMALL CRAFT
ADVISORY CONDITIONS WILL BE POSSIBLE AT THE END OF THE PERIOD.

&&

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

&&

$$

NEAR TERM...RGZ
SHORT TERM...MJC
LONG TERM...JDW
AVIATION...43








AREA FORECAST DISCUSSION

NWS WILMINGTON NC

 343 PM EDT FRI AUG 24 2012

.SYNOPSIS...
LOW PRESSURE WILL MOVE SLOWLY UP THE CAROLINA COAST OVERNIGHT.
HIGH PRESSURE WILL BUILD SOUTH THIS WEEKEND...BRINGING SLIGHTLY
DRIER AIR INTO THE REGION. TROPICAL STORM ISAAC IS EXPECTED TO
MOVE INTO THE EASTERN GULF OF MEXICO EARLY NEXT WEEK. REMNANTS
OF ISAAC COULD BRING UNSETTLED WEATHER TO THE CAROLINAS BY THE
MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 340 PM FRIDAY...MID TO UPPER LOW WILL TRACK UP THE SOUTHEAST
COAST THROUGH TONIGHT. THE H5 CIRCULATION REMAINS BROAD WITH
CENTER TIGHTENING A BIT OVERNIGHT WITH CENTER FORECAST OVER NC/VA
BORDER BY SAT MORNING. THE ASSOCIATED SURFACE LOW JUST E-SE OF
CAPE FEAR THIS AFTERNOON WILL MOVE NORTH AND BECOME MORE ELONGATED
AS IT WEAKENS THROUGH TONIGHT. NAM STILL SHOWING BEST ENERGY
ASSOCIATED WITH THIS LOW TO MOVE FROM COASTAL WATERS JUST SOUTH OF
CAPE FEAR DUE NORTH INTO NC THIS AFTERNOON. HRRR MODEL SHOWING
BEST CHC FOR HEAVIER PCP FROM THE TIP OF CAPE FEAR NORTH ALONG THE
NORTH CAROLINA COAST MAINLY FROM NEW HANOVER COUNTY THROUGH PENDER
COUNTY. THE BEST CHC OF HEAVIER PCP WILL OCCUR DURING THIS TIME
BUT BULLSEYE FOR HEAVIEST RAIN IN TSTMS WILL REMAIN OVER THE
WATERS TO THE EAST. THE GREATEST THREAT THROUGH WILL BE POTENTIAL
FOR FLOODING AS STEERING FLOW OVER MOST LAND AREAS WILL REMAIN
VERY WEAK. PCP WATER VALUES WILL REMAIN AROUND 2 INCHES UP THE
CAPE FEAR COAST DROPPING OFF AS YOU MOVE INLAND DOWN LESS THAN AN
INCH IN DRIER AIR AND SUBSIDENCE ON BACK END OF LOW WEST OF LOCAL
CWA...OVER CENTRAL TO WESTERN CAROLINAS. WILL KEEP LOW END POPS
INLAND AS SOME ENERGY ROTATES AROUND THE LOW...BUT OVERALL CLOUDS
AND COOLER NORTHERLY FLOW KEEPING TEMPS JUST AROUND 80 AND OVERALL
MORE STABLE ATMOSPHERE.

MODEL SOUNDINGS AND MOISTURE PROFILES SHOWING DRIER AIR WORKING
ITS WAY IN ON THE BACK EDGE OF LOW THROUGH THE MID TO UPPER
LEVELS TONIGHT AS IT LIFTS OFF TO THE NORTH. THIS WILL HELP PCP
SHUT OFF OVER LOCAL AREA. NAM SHOWS PCP WATER VALUES DROPPING
DOWN LESS THAN 1.5 INCHES BY SAT MORNING. CLOUDS...PCP AND FOG
WILL HELP KEEP TEMPS IN THE MID 60S AND CLOSER TO 70 WHERE GREATER
DEWPOINT AIR WILL HANG ON THE LATEST. MAY SEE STRATUS DEVELOP AS
MOISTURE BECOMES TRAPPED UNDER LOW LEVEL INVERSION...MORE PROBABLE
CLOSER TO THE COAST.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 340 PM FRIDAY...A DRIER PATTERN ANTICIPATED THIS WEEKEND...AS
DRY MID-LEVEL AIR OVERSPREADS THE REGION...AND A SURFACE LOW PULLS
SLUGGISHLY NORTH AND AWAY FROM OUR AREA. WEAK UPPER LOW POSITIONED
JUST NORTH OF OUR AREA SATURDAY AND SUNDAY WILL CONTINUE TO FEED
DRY AIR ALOFT...BUT CONCURRENTLY SHOULD PROMPT PLENTY OF DIURNAL
BUT MOSTLY CAPPED CUMULUS. CONVERGENCE OFFSHORE LATE IN THE PERIOD
MAY BRING COASTAL SHOWERS SUNDAY NIGHT. WHILE A SHOWER CANNOT BE
RULED OUT ON THE SEA BREEZE FRONT THIS WEEKEND...ACTIVITY SHOULD
IN OR BELOW THE ISOLATED CATEGORY.

MAXIMUM TEMPS WITH PARTIAL CLOUDS AND HIGH PRESSURE WEDGED IN FROM
THE NORTH...SHOULD RESULT IN MAINLY MIDDLE AND UPPER 80S BOTH DAYS.
MINIMUM TEMPS WILL DIP BELOW 70 MOST LOCATIONS BY DAYBREAK SAT/SUN
BUT QUITE A BIT MORE MILD AT THE COAST IN ONSHORE WIND DIRECTION.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 340 PM FRIDAY...SENSIBLE WEATHER THROUGH THE EXTENDED WILL
DEPEND ALMOST ENTIRELY ON ISAAC AND HIS POTENTIAL IMPACTS TO THE
REGION. STILL CONSIDERABLE UNCERTAINTY DUE TO TRACK
FORECASTS...WHICH...UNFORTUNATELY...WILL CREATE SIGNIFICANT
DIFFERENCES IN THE WEATHER ACROSS THE ILM CWA.

GFS/CMC ARE IN DECENT AGREEMENT WITH THEIR OVERALL EVOLUTION OF
ISAAC WHEN COMPARED TO THE ECMWF WHICH IS THE OUTLIER OF THE THREE
MODELS. WHILE THE ECMWF SLOWLY BRINGS ISAAC UP THROUGH THE GULF
COAST AND MEANDERS IT NW INTO THE TN VLY THROUGH MIDWEEK BEFORE
DISSIPATING...THE GFS/CMC BRING IT SLIGHTLY FURTHER EAST INTO THE
PANHANDLE OF FLORIDA ON TUESDAY AND THEN MAKE A SHARP
RECURVE...MOVING ISAAC`S REMNANTS BASICALLY OVER THE ILM CWA ON
WEDNESDAY. WILL LEAN TOWARDS THE GFS/CMC CONSENSUS...THE THINKING
THAT THE LARGE RIDGE WHICH FORCES THE ECMWF SOLUTION TO REMAIN WEST
IS OVERDONE. THIS MEANS DEEP S/SE FLOW MON/TUE WHICH SHOULD SUPPORT
ADVECTION SHOWERS...ESPECIALLY NEAR THE COAST...AND THEN A MUCH
WETTER DAY WEDNESDAY AS MID LEVEL THETA-E RIDGE ASSOCIATED WITH
ISAAC AND ITS REMNANTS...MOVES OVERHEAD. BY THURSDAY WE SHOULD BE ON
THE DRY WEST SUBSIDENT SIDE OF THE STORM AND WILL DRY OUT FOR LATE
WEEK. STILL MUCH UNCERTAINTY...BUT WILL RAMP POP UPWARDS THROUGH
WEDNESDAY BEFORE RAPIDLY TAILING OFF ON THURSDAY/FRIDAY.

NOTE THAT CURRENT FORECAST IS AT LEAST SLIGHTLY DIFFERENT THAN
HPC/NHC WHICH IS FAVORING A MUCH MORE WESTERN AND SLOWER
TRACK...ECMWF...FOR ISAAC. IF THE ECMWF TRACK WERE TO
VERIFY...WEDNESDAY WOULD STILL BE THE WETTEST DAY...SO POP TRENDS
WOULD STILL BE CORRECT...BUT OVERALL LESS RAINFALL ALONG WITH SLOWER
DECREASE IN POP WOULD BE NEEDED IN THAT SOLUTION (I.E. BETTER RAIN
CHANCES CONTINUING THROUGH THE END OF THE WEEK). WILL HAVE TO
MONITOR GUIDANCE TRENDS AND MODIFY FURTHER FORECAST UPDATES AS
NEEDED.

TEMPS WILL BE AROUND CLIMO MOST DAYS...WARMING TO ABOVE BY THE END
OF THE WEEK.

&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
AS OF 19Z...A STATIONARY FRONT IS LOCATED OFFSHORE WITH NE FLOW
IN THE LOW-LEVELS ACROSS THE TERMS. IFR CIGS ARE OCCURRING FROM
MYR S...WITH MVFR CEILINGS ACROSS THE REMAINING TERMS. WIDESPREAD
LIGHT TO OCCASIONALLY MODERATE RAIN IS OCCURRING...AND SO FAR ANY
THUNDERSTORMS HAVE REMAIN OFFSHORE. LOW PRESSURE IS CLEARLY SEEN
IN RADAR LOOPS SE OF CHS MOVING NE.

THINK THUNDERSTORMS WILL REMAIN CLOSEST TO THE ADVANCING LOW PRES.
THIS SHOULD KEEP BEST THUNDERSTORM POTENTIAL OFFSHORE TO SOUTHEAST
OF CRE/MYR...WITH THUNDERSTORMS MOST LIKELY AFFECTING ILM WITH AT
LEAST VCTS AFT 19-20Z. THROUGH 22Z TEMPO MVFR CONDITIONS COULD
OCCUR AT FLO/LBT...WITH MVFR/TEMPO IFR AT CRE/MYR. ILM TERMINAL
SHOULD HAVE THE BEST POTENTIAL FOR IFR THIS AFTERNOON...BUT IF
THE LOW PASSES TOO FAR OFFSHORE...THEN VCTS/IFR WOULD BE LESS
LIKELY.

PRECIPITATION WILL SLOWLY DECREASE AND BY EVENING SHOULD BE
NORTHEAST OF FLO/MYR/CRE AND BY LATE EVENING NORTHEAST OF ALL THE
TERMINALS. SUBSIDENCE IN THE WAKE OF THE PRECIPITATION SHOULD ALLOW
FOR A A GOOD CHANCE OF MVFR VSBYS DEVELOPING AT ALL TERMINALS...AND
IFR CIGS AT THE COASTAL TERMINALS OVERNIGHT.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 340 PM FRIDAY...MID TO UPPER LOW MOVE UP INTO NORTH CAROLINA
WITH CENTER REACHING THE NC/VA BORDER BY MORNING. AT THE SAME TIME
AN ASSOCIATED AREA OF LOW PRESSURE WILL TRACK SLOWLY UP THROUGH THE
LOCAL COASTAL WATERS REACHING TOWARD HATTERAS AFTER MIDNIGHT.
THIS WILL HELP TO PRODUCE MORE WIDESPREAD PRECIPITATION IN
SHWRS/TSTMS THROUGH THIS EVENING...WINDING DOWN FROM S TO N TONIGHT.

SFC WINDS 10 TO 15 KTS WILL DIMINISH A BIT OVERNIGHT AS THEY BACK
TOWARD THE NW. THIS OFF SHORE FLOW WILL ACT TO LOWER SEAS BUT A
LONGER PERIOD E-SE SWELL UP TO 16 SECONDS WILL COUNTERACT THIS OFF
SHORE FLOW AND WILL PRODUCE A SLIGHT INCREASE IN OVERALL SEAS
OVERNIGHT. SEAS WILL BUILD TO 3 TO 4 FT MAINLY ACROSS THE OUTER
WATERS. EXPECT ROUGHER SEAS WITH HIGHER WINDS AND SEAS IN TSTMS
THROUGH THIS EVENING AND ALSO REDUCED VSBYS DUE TO HEAVY RAIN. RADAR
CONTINUED TO SHOW THE POSSIBILITY OF WATERSPOUTS IN STORMS OVER THE
OUTER COASTAL WATERS THIS AFTERNOON.



SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 340 PM FRIDAY...OUTSIDE OF TSTMS WINDS WILL REMAIN MANAGEABLE
SATURDAY AND SUNDAY...AS A SURFACE LOW OVER THE WATERS MOVES
SLOWLY NORTH OF THE AREA. WINDS WILL VEER EAST SUNDAY AS HIGH
PRESSURE CONSOLIDATES OVER NEW ENGLAND. THE COMBINATION OF WIND-
WAVES AND SWELL WAVES WILL KEEP SEAS MAINLY 3-4 FEET THIS WEEKEND
AND UP TO 5 FEET AT TIMES WELL OFFSHORE. NUMEROUS SHOWERS AND
TSTMS WILL BECOME SCATTERED TO ISOLATED THIS WEEKEND...AS THE SFC
LOW PULLS NORTH OF SURF CITY BY DAYBREAK SATURDAY...AND DRY AIR
ALOFT HELPS TO SQUELCH STORM DEVELOPMENT.


LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 340 PM FRIDAY...QUITE A BIT OF UNCERTAINTY THROUGH THE
EXTENDED AS WIND/WAVE CONDITIONS COULD VARY CONSIDERABLY DEPENDING
ON WHAT HAPPENS WITH TS ISAAC. ANTICIPATE E/SE WINDS MON THROUGH TUE
AS ISAAC MOVES ALONG THE WEST COAST OF FLORIDA AND INTO THE GULF
COAST REGION. THE CONTINUED E/SE WINDS AROUND 10 KTS...UP TO 15 KTS
ACROSS THE SOUTHERN WATERS...WILL GENERATE 2-4 FT SOUTHERLY WIND
WAVES. THESE WIND WAVES WILL COMBINE WITH WHAT SHOULD BE INCREASING
S/SE SWELL OF 4-5FT/9SEC DUE TO TROPICAL SYSTEMS ISAAC AND JOYCE.
GUIDANCE IS NOT VERY ROBUST IN DEVELOPING ANY SIGNIFICANT VERY LONG
PERIOD SWELL...BUT NEVERTHELESS...3-5 FT SEAS ARE EXPECTED THROUGH
TUESDAY...WITH 6 FOOTERS POSSIBLE ACROSS THE SOUTHERN WATERS. SEAS
COULD BUILD MUCH HIGHER WEDNESDAY...ESPECIALLY IF GFS/CMC ARE
CORRECT...DUE TO INCREASING SOUTHERLY WINDS...AND SMALL CRAFT
ADVISORY CONDITIONS WILL BE POSSIBLE AT THE END OF THE PERIOD.

&&

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

&&

$$

NEAR TERM...RGZ
SHORT TERM...MJC
LONG TERM...JDW
AVIATION...MRR/RGZ





AREA FORECAST DISCUSSION

NWS WILMINGTON NC

 219 PM EDT FRI AUG 24 2012

.SYNOPSIS...
LOW PRESSURE WILL MOVE SLOWLY UP THE CAROLINA COAST THROUGH TONIGHT.
HIGH PRESSURE WILL BUILD SOUTHWARD DURING THE WEEKEND...BRINGING
SLIGHTLY DRIER AIR. TROPICAL STORM ISAAC MAY FINALLY REACH HURRICANE
STRENGTH ONCE IT MOVES OUT OF THE CARIBBEAN SEA AND INTO THE GULF OF
MEXICO EARLY NEXT WEEK. REFER TO THE LATEST BULLETINS ISSUED BY THE
NATIONAL HURRICANE CENTER.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM FRIDAY...MID TO UPPER LOW WILL TRACK UP THE THE
SOUTHEAST COAST THROUGH TONIGHT. THE H5 CIRCULATION REMAINS BROAD
WITH CENTER TIGHTENING A BIT OVERNIGHT WITH CENTER FORECAST
OVER NC/VA BORDER BY SAT MORNING. THE ASSOCIATED SURFACE LOW JUST
E-SE OF CAPE FEAR THIS AFTERNOON WILL MOVE NORTH AND BECOME MORE
ELONGATED AS IT WEAKENS THROUGH TONIGHT. NAM STILL SHOWING BEST
ENERGY ASSOCIATED WITH THIS LOW TO MOVE FROM COASTAL WATERS JUST
SOUTH OF CAPE FEAR DUE NORTH INTO NC THIS AFTERNOON. HRRR MODEL
SHOWING BEST CHC FOR HEAVIER PCP FROM THE TIP OF CAPE FEAR NORTH
ALONG THE NORTH CAROLINA COAST MAINLY FROM NEW HANOVER COUNTY
THROUGH PENDER COUNTY. THE BEST CHC OF HEAVIER PCP WILL OCCUR
DURING THIS TIME BUT BULLSEYE FOR HEAVIEST RAIN IN TSTMS WILL
REMAIN OVER THE WATERS TO THE EAST. THE GREATEST THREAT THROUGH
WILL BE POTENTIAL FOR FLOODING AS STEERING FLOW OVER MOST LAND
AREAS WILL REMAIN VERY WEAK. PCP WATER VALUES WILL REMAIN AROUND 2
INCHES UP THE CAPE FEAR COAST DROPPING OFF AS YOU MOVE INLAND DOWN
LESS THAN AN INCH IN DRIER AIR AND SUBSIDENCE ON BACK END OF LOW
WEST OF LOCAL CWA...OVER CENTRAL TO WESTERN CAROLINAS. WILL KEEP
LOW END POPS INLAND AS SOME ENERGY ROTATES AROUND THE LOW...BUT
OVERALL CLOUDS AND COOLER NORTHERLY FLOW KEEPING TEMPS JUST AROUND
80 AND OVERALL MORE STABLE ATMOSPHERE.

MODEL SOUNDINGS AND MOISTURE PROFILES SHOWING DRIER AIR WORKING
ITS WAY IN ON THE BACK EDGE OF LOW THROUGH THE MID TO UPPER
LEVELS TONIGHT AS IT LIFTS OFF TO THE NORTH. THIS WILL HELP PCP
SHUT OFF OVER LOCAL AREA. NAM SHOWS PCP WATER VALUES DROPPING
DOWN LESS THAN 1.5 INCHES BY SAT MORNING. CLOUDS...PCP AND FOG
WILL HELP KEEP TEMPS IN THE MID 60S AND CLOSER TO 70 WHERE GREATER
DEWPOINT AIR WILL HANG ON THE LATEST. MAY SEE STRATUS DEVELOP AS
MOISTURE BECOMES TRAPPED UNDER LOW LEVEL INVERSION...MORE PROBABLE
CLOSER TO THE COAST.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 AM FRIDAY...MID LEVEL LOW PRESSURE WILL DRIFT SLOWLY TO
THE NORTHEAST AS HIGH PRESSURE BUILDS IN. SATURDAY SHOULD BE DRY AS
THERE IS NOW A CONSIDERABLE SUBSIDENCE INVERSION AROUND 800MB. THE
PRECIPITABLE WATERS DROPPING TO JUST OVER ONE INCH MAY BE A BIT ON
THE DRY SIDE AS THE GFS DOES NOT SEEM TO BE HANDLING THE MASS OF DRY
AIR ACROSS THE MISSISSIPPI VALLEY VERY WELL. THE HIGH RETREATS
NORTHEAST SLIGHTLY SUNDAY AND SLIGHT CHANCE POPS ARE WARRANTED AS
SOUNDINGS BECOME MORE FAVORABLE.

TEMPERATURE FORECAST IS CHALLENGING AS THE 0000 UTC GUIDANCE IS ALL
OVER THE PLACE. FOR EXAMPLE...THERE IS A SIX DEGREE SPREAD WITH
WILMINGTON SATURDAY WITH WARMER MET NUMBERS. THERE IS ALSO A SIX
DEGREE SPREAD IN LUMBERTON FOR SUNDAY WITH THE MAV MUCH WARMER. I
HAVE GENERALLY LEANED TOWARD THE WARMER NUMBERS WHICH HAS BEEN A
WINNING STRATEGY FOR MOST OF THE SUMMER.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 3 AM FRIDAY...FORECAST CONFIDENCE REMAINS LOW AS SENSIBLE
WEATHER ELEMENTS WILL BE MOSTLY DRIVEN BY THE EVENTUAL TRACK OF
ISAAC. MAINTAINED THE HIGHER TREND OF POPS THROUGH THE PERIOD BUT
SUBSEQUENT SHIFTS MAY WANT TO CONTEMPLATE INTRODUCING A DECREASING
TREND AS ONLY LIMITED FORCING AND MOISTURE WILL BE AVAILABLE IF THE
WESTERN SCENARIO/TRACK VERIFIES. THIS FORCING WILL BE BROAD SPEED
CONVERGENCE WITH THE SOUTHEASTERLY FLOW WHICH GENERALLY DOES NOT YIELD
THAT MUCH FOR OUR AREA...AT LEAST INLAND. THE REMAINDER OF THE
PERIOD WOULD BE MODULATED BY A WEAK FRONT LINGERING IN THE AREA. NO
CHANGES TO TEMPERATURE FORECAST.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 18Z...A STATIONARY FRONT IS LOCATED OFFSHORE WITH NE FLOW IN
THE LOW-LEVELS ACROSS THE TERMS. IFR CIGS ARE OCCURRING FROM MYR
S...WITH MVFR CEILINGS ACROSS THE REMAINING TERMS. WIDESPREAD LIGHT
TO OCCASIONALLY MODERATE RAIN IS OCCURRING...AND SO FAR ANY
THUNDERSTORMS HAVE REMAIN OFFSHORE. LOW PRESSURE IS CLEARLY SEEN IN
RADAR LOOPS SE OF CHS MOVING NE.

THINK THUNDERSTORMS WILL REMAIN CLOSEST TO THE ADVANCING LOW
PRESSURE. THIS SHOULD KEEP BEST THUNDERSTORM POTENTIAL OFFSHORE TO
THE SOUTHEAST OF CRE/MYR...WITH THUNDERSTORMS MOST LIKELY AFFECTING
ILM WITH AT LEAST VCTS AFT 19-20Z. THROUGH 22Z TEMPO MVFR CONDITIONS
COULD OCCUR AT FLO/LBT...WITH MVFR/TEMPO IFR AT CRE/MYR. THE ILM
TERMINAL SHOULD HAVE THE BEST POTENTIAL FOR IFR THIS AFTERNOON...BUT
IF THE LOW PASSES TOO FAR OFFSHORE...THEN VCTS/IFR WOULD BE LESS LIKELY.

PRECIPITATION WILL SLOWLY DECREASE AND BY EVENING SHOULD BE
NORTHEAST OF FLO/MYR/CRE AND BY LATE EVENING NORTHEAST OF ALL THE
TERMINALS. SUBSIDENCE IN THE WAKE OF THE PRECIPITATION SHOULD ALLOW
FOR A A GOOD CHANCE OF MVFR VSBYS DEVELOPING AT ALL TERMINALS...AND
IFR CIGS AT THE COASTAL TERMINALS OVERNIGHT.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM FRIDAY...SHORTWAVE WILL RIDE UP THE CAPE FEAR COAST
REACHING THE NC/VA BORDER BY MORNING. AT THE SAME TIME AN
ASSOCIATED AREA OF LOW PRESSURE WILL TRACK SLOWLY UP THROUGH THE
LOCAL COASTAL WATERS REACHING TOWARD HATTERAS AFTER MIDNIGHT. THIS
WILL HELP TO PRODUCE MORE WIDESPREAD PRECIPITATION THROUGH THIS
EVENING...WINDING DOWN FROM S TO N TONIGHT... LINGERING LONGEST
OFF THE CAPE FEAR COAST...AND PERHAPS WELL INTO THE NIGHT.

SFC WINDS SPEEDS WILL GENERALLY BE 10 TO 15 KT AND MAY BECOME
GUSTY FOR A TIME LATER TODAY. THE DIRECTION WILL REMAIN N TO NE.
ALTHOUGH SURFACE WINDS REMAIN N-NE...INCREASING LOW LEVEL FLOW
ABOVE THE SURFACE WILL STEER THE STORMS TOWARD THE N-NW THROUGH
THE DAY.

SEAS WILL BUILD TO 3 TO 4 FT ALTHOUGH SEAS MAY REACH 5 FT OR SO...
MAINLY ACROSS THE OUTER WATERS OFF OF CAPE FEAR. MARINERS SHOULD
EXPECT HIGHER WINDS AND SEAS IN THE VICINITY OF PERSISTENT
THUNDERSTORM ACTIVITY. THE VISIBILITY WILL FREQUENTLY BE REDUCED TO
1 NM OR LESS IN RAIN. GIVEN THE COVERAGE OF CONVECTION...SEAS WILL
LIKELY BE ROUGH. AN ELEVATED RISK FOR WATERSPOUTS WILL REMAIN FOR
ONE MORE DAY.

THE BUOYS CONTINUE TO SAMPLE A WEAK ESE SWELL THIS MORNING UP TO
16 SECONDS. THE SWELL WILL BECOME MORE SIGNIFICANT IN THE COMING DAYS.
THE SWELL PERIOD WILL BE ON THE ORDER OF 11 TO 14 SECONDS.

SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 AM FRIDAY...MOST OF THE FORECAST PERIOD WILL BE
CHARACTERIZED BY LIGHT WIND FIELDS. SHOULD SEE NORTHEAST WINDS TEN
KNOTS OR LESS THROUGH EARLY SUNDAY. WINDS VEER AND INCREASE TO 10-15
LATER SUNDAY CONTINUING INTO EARLY MONDAY. SWAN IS ADVERTISING SEAS
INCREASING FROM AN EARLY RANGE OF 2-4 FEET TO 3-6 FEET LATE VIA A
SIGNIFICANT SWELL COMPONENT.

LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 3 AM FRIDAY...EXPECT NORTHEAST WINDS INITIALLY VEERING TO
EAST LATE MONDAY AND FINALLY TO THE SOUTHEAST TUESDAY. SPEEDS WILL
GENERALLY BE TEN KNOTS OR LESS. SOME LINGERING SWELL FROM DISTANT
TROPICAL SYSTEM ISAAC AND JOYCE FOR THAT MATTER WILL KEEP SEAS
HIGHER THAN WINDS FIELDS WOULD NORMALLY SIGNAL WITH 3-6 FEET BOTH
DAYS.

&&

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

&&

$$

NEAR TERM...RGZ
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...RGZ/MRR









AREA FORECAST DISCUSSION

NWS NORMAN OK

 1205 AM CDT FRI AUG 24 2012

.AVIATION... 24/06Z TAFS...VFR FORECAST WITH MVFR CONDITIONS IN/NEAR
THUNDERSTORMS. SOME MVFR STRATUS FORECAST BY A FEW MODELS ACROSS
CENTRAL AND SOUTHWEST OKLAHOMA...BUT CONFIDENCE NOT HIGH ENOUGH TO
MENTION. AREA OF RAIN WITH EMBEDDED THUNDERSTORMS EXPECTED TO MOVE
INTO NORTHWEST PORTIONS OF OKLAHOMA AFTER MIDNIGHT THEN PROGRESS
EASTWARD AND WEAKEN THROUGH THE EARLY MORNING HOURS. WILL KEEP TEMPO
MENTIONED MAINLY NORTHWEST AND NORTH-CENTRAL OKLAHOMA TERMINALS.
ADDITIONAL STORMS MAY DEVELOP LATE TOMORROW NEAR WESTERN OKLAHOMA
TERMINALS SO WILL INCLUDE PROB30 LATE IN FORECAST. WILL KEEP THE
/AMD NOT SKED/ AT KCSM WHERE FAA COMMS ISSUES CONTINUE.

&&

.PREV DISCUSSION... /ISSUED 1007 PM CDT THU AUG 23 2012/

.UPDATE...
A MINOR UPDATE HAS BEEN SENT TO ADJUST POPS A BIT THROUGH THIS
EVENING.

&&

.DISCUSSION...
TWO AREAS OF MOIST CONVECTION ARE PRESENT THIS EVENING OUTSIDE OF
OUR FA. THE FIRST...AND MORE ORGANIZED...IS LOCATED ACROSS NORTH
CENTRAL AND WEST CENTRAL KS. THE OTHER LOOSELY DEFINED AREA
EXTENDS FROM THE TX PANHANDLE SSWD THROUGH SE NM AND WEST
TX...AHEAD OF AN APPROACHING UPPER LOW CLEARLY SEEN PASSING OVER
THE FOUR CORNERS REGION. MOST OF THE MODELS GENERALLY HAVE SOME
CLUE WITH REGARDS TO THIS ACTIVITY...BUT PREVIOUS HRRR RUNS AND
ECMWF APPEAR TO HAVE THE BEST IDEA. THAT BEING SAID...A LLJ WILL
DEVELOP SIMILAR TO LAST NIGHT WEST OF I35. THE PREVIOUS MAY HELP
MAINTAIN/AMPLIFY THIS ACTIVITY AS IT APPROACHES BOTH FROM THE WEST
AND NORTH ESPECIALLY ACROSS WESTERN AND NORTHERN OKLAHOMA THROUGH
THE EARLY MORNING HOURS.

&&

.PREV DISCUSSION... /ISSUED 650 PM CDT THU AUG 23 2012/

AVIATION...
24/00Z TAFS...PRIMARILY VFR FORECAST WITH MVFR CONDITIONS IN/NEAR
THUNDERSTORMS. AREA OF RAIN WITH EMBEDDED THUNDERSTORMS PROGD BY
MOST MODELS TO MOVE INTO NORTHWEST PORTIONS OF OKLAHOMA TOWARD AND
AFTER MIDNIGHT THEN PROGRESS EASTWARD AND WEAKEN THROUGH TOMORROW
MORNING. LATEST HRRR AND RECENT RUNS OF OUNWRF SUPPORT THIS IDEA.
WILL KEEP TEMPO MENTIONED MAINLY AT NORTHERN AND FAR WESTERN
OKLAHOMA TERMINALS WHERE COVERAGE MAY BE A BIT HIGHER. WILL
INCLUDE /AMD NOT SKED/ AT KCSM WHERE FAA COMMS ISSUES CONTINUE.

PREV DISCUSSION... /ISSUED 336 PM CDT THU AUG 23 2012/

DISCUSSION...
SCATTERED LIGHT SHOWERS ASSOCIATED WITH MID-LEVEL
CLOUDS...CONTINUE TO DRIFT ACROSS OKLAHOMA AND THE TEXAS
PANHANDLE THIS AFTERNOON IN ADVANCE OF AN UPPER TROUGH.
THE UPPER TROUGH/LOW OVER SOUTHERN UTAH WILL NOT MOVE
ACROSS THE SOUTHERN PLAINS UNTIL SATURDAY/SUNDAY.

MEANWHILE...IT APPEARS BETTER CHANCES FOR SHOWERS/SOME STORMS
WILL BE ACROSS PARTS OF WESTERN AND NORTHERN OKLAHOMA NEAR A
STRONGER LOW LEVEL FLOW AND MID-LEVEL MOISTURE. IF A LARGE ENOUGH
AREA OF PRECIP CAN DEVELOP...BETTER CHANCES OF RAIN/STORMS MAY
MOVE INTO CENTRAL AND SOUTHERN OKLAHOMA TONIGHT INTO FRIDAY NIGHT.
MODELS AND HPC GUIDANCE CONTINUE TO SHOW THE POTENTIAL FOR 1 TO 3
INCH RAINFALL AMOUNTS THROUGH EARLY SUNDAY...MAINLY NORTHWEST OF
I-44.

AFTER SUNDAY/MONDAY...HEIGHT RISES ASSOCIATED WITH A
STRENGTHENING MID/UPPER LEVEL RIDGE WILL BRING DRY AND
HOTTER CONDITIONS TUESDAY INTO THURSDAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK  91  69  86  72 /  20  20  40  60
HOBART OK         89  68  89  70 /  30  50  50  50
WICHITA FALLS TX  94  70  91  74 /  20  20  30  30
GAGE OK           89  68  90  69 /  30  60  50  60
PONCA CITY OK     92  69  85  71 /  20  40  50  60
DURANT OK         90  68  89  73 /  10  10  20  40

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&

$$

03/11




AREA FORECAST DISCUSSION

NWS SAN ANGELO TX

 944 PM CDT SAT AUG 25 2012

.UPDATE...
SENT A QUICK UPDATE OUT FOR THE FORECAST PACKAGE WITH MINOR
CHANGES MADE TO OVERNIGHT LOWS...WINDS AND SKY COVER.

&&

.DISCUSSION...
A COMPLEX OF WEAKLY ORGANIZED STORMS CONTINUES TO MOVE SLOWLY TO
THE EAST ACROSS THE WESTERN BIG COUNTRY...GENERALLY WEST OF A TYE
TO HASKELL LINE AS OF 930 PM. MODEST LARGE SCALE ASCENT WAS NOTED
ON THE WATER VAPOR LOOP IN RESPONSE TO A SHORTWAVE TROF OVER
SOUTHEAST NM. INSTABILITY LOOKS TO BE RATHER LIMITED...AT LEAST
BASED ON RAP DEPENDENT MESO ANALYSIS...WITH AN AREA OF MUCAPE
VALUES AROUND 1000 J/KG OVER THE AREA CURRENTLY EXPERIENCING
CONVECTION. EFFECTIVE SHEAR VALUES IN THE 25-30 KT RANGE SUGGEST
THAT MULTICELLULAR MODE MAY BE SUSTAINED FOR SEVERAL MORE
HOURS...ESPECIALLY AS THE LOW LEVEL JET DEVELOPS DURING THE
OVERNIGHT HOURS. WE COULD SEE ADDITIONAL CONVECTIVE DEVELOPMENT...
MAINLY SHOWERS...OVER THE HEARTLAND OVERNIGHT. INHERITED POPS WERE
LEFT INTACT WITH MINOR CHANGES MADE TO WINDS...SKY COVER AND
OVERNIGHT LOW TEMPS.

JOHNSON

&&

.PREV DISCUSSION... /ISSUED 603 PM CDT SAT AUG 25 2012/

DISCUSSION...
SEE AVIATION DISCUSSION BELOW...

AVIATION...
ISOLATED SHOWERS AND THUNDERSTORMS CONTINUE ACROSS THE AREA. I
LEFT IN A MENTION OF VCTS AT KABI...KSJT AND KBBD WHERE THE BEST
CHANCE OF SEEING A THUNDERSTORM EXISTS. BRIEF MVFR CONDITIONS WILL
BE POSSIBLE WITHIN ANY THUNDERSTORMS. MOST OF THIS ACTIVITY SHOULD
BEGIN TO DISSIPATE BY 02Z. SOUTH SOUTHEAST WINDS WILL REMAIN LIGHT
OVERNIGHT. A WEAK COLD FRONT IS FORECAST TO MOVE INTO THE NORTHERN
BIG COUNTRY SUNDAY AFTERNOON...WITH ISOLATED TO SCATTERED SHOWERS
AND THUNDERSTORMS DEVELOPING. I WENT AHEAD AND INCLUDED A VCTS
GROUP AFTER 19Z AT BOTH KABI AND KSJT WHERE THE BEST CHANCE OF
SEEING CONVECTION LIES. OTHERWISE...EXPECT VFR CONDITIONS TO
PREVAIL THROUGH THE NEXT 24 HOURS.

PREV DISCUSSION... /ISSUED 337 PM CDT SAT AUG 25 2012/

SHORT TERM...
CLOUD COVER ASSOCIATED FROM SHOWERS LAST NIGHT HAS LARGELY
DISSIPATED THIS AFTERNOON...AND WITH MORE SUNSHINE AND RAPIDLY
WARMING TEMPERATURES...HAVE STARTED TO SEE CONVECTION DEVELOP. SO
FAR...THE STORMS HAVE REMAINED ALONG THE WESTERN BORDER OF THE
AREA...WHERE THE MODELS HAVE SHOWN THE LOW TO MID LEVEL THETA E
AXIS TO REMAIN. GIVEN THE FAIRLY UNSTABLE...RELATIVELY UNCAPPED
AIR MASS...IN PLACE CANT REALLY RULE OUT A STORM JUST ABOUT
ANYWHERE. BUT BEST CHANCES LOOK TO BE ACROSS THE NORTHERN AND
WESTERN BIG COUNTRY...WITH THE CONVECTION EVENTUALLY SETTLING INTO
THE INTERSTATE 20 CORRIDOR THIS EVENING. THIS IDEA WELL CORRELATED
WITH THE TTU WRF AS WELL...SO SOME CONFIDENCE IN THIS SCENARIO.

WEAK FRONTAL BOUNDARY DROPS THROUGH THE PANHANDLE AND INTO THE BIG
COUNTRY BY SUNDAY AFTERNOON. CONVERGENCE WILL LIKELY BE PRETTY
WEAK...BUT AGAIN...GIVEN THE AIR MASS IN PLACE...WONT TAKE MUCH.
TTU WRF AGAIN SHOWS A FEW STORMS SUNDAY AFTERNOON ACROSS THE
AREA...MAINLY ALONG THE FRONT...WHERE THE GFS IS ALSO SHOWING THE
BEST LOW LEVEL THETA E AXIS. WILL USE THIS AS A BASIS FOR THE
SUNDAY POP FORECAST.

LONG TERM...
RETAINING SLIGHT CHANCE POPS THROUGH MONDAY. UPPER HIGH WILL BUILD
EARLY NEXT WEEK OVER COLORADO/NEW MEXICO WITH NORTH-NORTHEAST
FLOW ALOFT DEVELOPING OVER OUR AREA. THE GFS AND NAM SHOW A COUPLE
OF WEAK DISTURBANCES ALOFT MOVING DOWN INTO OUR AREA. AIRMASS
LOOKS TO REMAIN SUFFICIENTLY MOIST FOR THE POSSIBILITY OF ISOLATED
TO SCATTERED SHOWERS/THUNDERSTORMS. IN ADDITION...WITH A SURFACE
HIGH BUILDING INTO THE MIDWEST AND CENTRAL PLAINS...COULD HAVE A
WEAK COLD FRONTAL BOUNDARY SAGGING SOUTH ACROSS OUR AREA ON
MONDAY. SURFACE CONVERGENCE ALONG THIS BOUNDARY WILL BE RATHER
WEAK... HOWEVER.

THOUGH THE TIMING IS UNCERTAIN...THE 12Z MODELS INDICATE THE
POTENTIAL FOR AN ADDITIONAL DISTURBANCE ALOFT TO DROP SOUTH-
SOUTHWEST INTO OUR WEST CENTRAL TEXAS ON TUESDAY...WITH AN
ATTENDANT INCREASE IN MOISTURE/PRECIPITABLE WATER. HAVE DECIDED TO
CARRY A SLIGHT CHANCE POP IN THE EAST-CENTRAL PART OF OUR AREA FOR
TUESDAY.

DRIER AIR IS PROGGED TO WORK ITS WAY SOUTH-SOUTHWEST INTO OUR AREA
BY LATE WEDNESDAY AND REMAIN OVER OUR AREA TO THE END OF THE WEEK.
THIS WILL RESULT IN LESS CLOUD COVER ACROSS OUR AREA. WITH LIGHT
WINDS AT NIGHT...THIS SHOULD ALSO ALLOW TEMPERATURES TO DROP INTO
THE MID TO UPPER 60S FOR LOWS THURSDAY AND FRIDAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
ABILENE  73  93  73  93  69 /  30  30  20  20  10
SAN ANGELO  74  94  73  96  70 /  20  20  20  20  10
JUNCTION  75  93  72  95  69 /  10  10  20  20  10

&&

.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

25







AREA FORECAST DISCUSSION

NWS SAN ANGELO TX

 1234 PM CDT FRI AUG 24 2012



.DISCUSSION...
/SEE BELOW FOR AVIATION DISCUSSION/

&&

.AVIATION...
GUSTY WINDS TO 25 KTS WILL BE THE MAIN IMPACT ON TERMINALS THIS
AFTERNOON...AS BAND OF MID LEVEL CLOUDS AND VERY LIGHT SHOWERS
MOVE SLOWLY EAST ACROSS THE REGION. THUNDER POSSIBLE BUT SHOULD
BE ISOLATED.

&&

.PREV DISCUSSION... /ISSUED 627 AM CDT FRI AUG 24 2012/

DISCUSSION...

LOOK FOR VFR CONDITIONS TO DOMINATE WEST CENTRAL TEXAS FOR THE
NEXT 24 HOURS. AVIATION BELOW HAS DETAILS.

AVIATION...

SHOWERS AND THUNDERSTORMS MAY DEVELOP ACROSS WEST CENTRAL TEXAS
TODAY AND TONIGHT. A TROUGH OF LOW PRESSURE ALOFT...WILL CONTINUE
TO MOVE SLOWLY EAST INTO THE CENTRAL TEXAS TODAY AND TONIGHT. THIS
FEATURE MAY PROVIDE THE NECESSARY UPPER DYNAMICS TO INITIATE
SHOWERS AND THUNDERSTORMS. OTHERWISE...PLAN FOR GUSTY SOUTH
SURFACE WINDS ACROSS WEST CENTRAL TEXAS TODAY...ESPECIALLY ACROSS
THE BIG COUNTRY AND CONCHO VALLEY. TONIGHT...SURFACE WINDS WILL
DIMINISH TO AROUND 10 KNOTS OR LESS.

HUBER

PREV DISCUSSION... /ISSUED 328 AM CDT FRI AUG 24 2012/

SHORT TERM...
RAIN CHANCES FOR MOST OF WEST CENTRAL TEXAS LOOK SOMEWHAT PROMISING
FOR THE NEXT 24 HOURS. MODELS INDICATE A SHORT WAVE TROUGH OF LOW
PRESSURE WILL PROVIDE SOME UPPER-LEVEL DYNAMICS. MODELS SHOW THIS
FEATURE BEST AT 700 MB. ALTHOUGH THE NAM AND THE RUC (HIGH
RESOLUTION RAPID REFRESH) INDICATE SOME DECLINE IN CONVECTIVE
COVERAGE BETWEEN NOW AND 18Z...I DECIDED TO INCLUDE THE FIRST 6
HOURS OF THE TODAY PERIOD WITH SLIGHT CHANCE TO CHANCE POPS ACROSS
THE BOARD. IN ADDITION...MODELS CONTINUE AT LEASE A SLIGHT CHANCE
THROUGH TONIGHT. ALSO...HPC QPF GRIDS FOR THE FIRST 24 HOURS LOOK
REASONABLE.

AS FOR TEMPERATURES...NUMBERS CLOSE TO MEX MOS LOOK ON TRACK FOR
TODAY AND TONIGHT. LIMITED SUNSHINE AND NORTHWEST FLOW ALOFT WILL
HOLD AFTERNOON HIGHS TODAY MAINLY IN THE LOWER TO MID 90S. OVERNIGHT
LOWS TONIGHT WILL BE MAINLY IN THE LOWER TO MID 70S.

HUBER

LONG TERM...
BY SATURDAY MORNING THE MID LEVEL TROUGH AXIS WILL STRETCH
NORTHEASTWARD FROM SOUTHERN NEW MEXICO ACROSS THE NORTHERN
PANHANDLE AND INTO THE CENTRAL PLAINS. THE SLOW MOVING UPPER
TROUGH AXIS WILL FINALLY MOVE EAST OF THE FORECAST AREA BY LATE
SUNDAY. UNTIL THEN...ISOLATED TO SCATTERED THUNDERSTORMS WILL BE
POSSIBLE OVER MUCH OF THE FORECAST AREA...FAVORING THE WESTERN AND
NORTHERN CWA.

WITH AN INCREASE IN CLOUD COVER...AFTERNOON HIGHS WILL REMAIN IN
THE LOW TO MID 90S THROUGH THE WEEKEND. MORNING LOWS WILL BE IN
THE LOWER 70S.

UPPER LEVEL HILL PRESSURE WILL BUILD INTO THE AREA IN THE WAKE OF
THE DEPARTING UPPER LEVEL TROUGH INTO THE FIRST OF THE COMING
WEEK. THE CENTER OF THE UPPER LEVEL HIGH WILL SETTLE OVER NEW
MEXICO. WITH THE UPPER RIDGE AND SUNNY SKIES DOMINATING THE AREA
AT LEAST THROUGH THE MIDDLE OF NEXT WEEK...AFTERNOON TEMPERATURES
WILL EDGE A LITTLE HIGHER TO THE MID TO UPPER 90S. LOOKING FOR A
DRY FORECAST FOR THE REMAINDER OF THE EXTENDED.

&&

.PRELIMINARY POINT TEMPS/POPS...
ABILENE  73  95  73  93  71 /  20  20  20  20  20
SAN ANGELO  73  95  74  94  71 /  20  20  20  20  20
JUNCTION  74  92  72  94  72 /  10  10  10  10  10

&&

.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

99/99/04






AREA FORECAST DISCUSSION

NWS SAN ANGELO TX

 627 AM CDT FRI AUG 24 2012

.DISCUSSION...

LOOK FOR VFR CONDITIONS TO DOMINATE WEST CENTRAL TEXAS FOR THE
NEXT 24 HOURS. AVIATION BELOW HAS DETAILS.

&&

.AVIATION...

SHOWERS AND THUNDERSTORMS MAY DEVELOP ACROSS WEST CENTRAL TEXAS
TODAY AND TONIGHT. A TROUGH OF LOW PRESSURE ALOFT...WILL CONTINUE
TO MOVE SLOWLY EAST INTO THE CENTRAL TEXAS TODAY AND TONIGHT. THIS
FEATURE MAY PROVIDE THE NECESSARY UPPER DYNAMICS TO INITIATE
SHOWERS AND THUNDERSTORMS. OTHERWISE...PLAN FOR GUSTY SOUTH
SURFACE WINDS ACROSS WEST CENTRAL TEXAS TODAY...ESPECIALLY ACROSS
THE BIG COUNTRY AND CONCHO VALLEY. TONIGHT...SURFACE WINDS WILL
DIMINISH TO AROUND 10 KNOTS OR LESS.

HUBER

&&

.PREV DISCUSSION... /ISSUED 328 AM CDT FRI AUG 24 2012/

SHORT TERM...
RAIN CHANCES FOR MOST OF WEST CENTRAL TEXAS LOOK SOMEWHAT PROMISING
FOR THE NEXT 24 HOURS. MODELS INDICATE A SHORT WAVE TROUGH OF LOW
PRESSURE WILL PROVIDE SOME UPPER-LEVEL DYNAMICS. MODELS SHOW THIS
FEATURE BEST AT 700 MB. ALTHOUGH THE NAM AND THE RUC (HIGH
RESOLUTION RAPID REFRESH) INDICATE SOME DECLINE IN CONVECTIVE
COVERAGE BETWEEN NOW AND 18Z...I DECIDED TO INCLUDE THE FIRST 6
HOURS OF THE TODAY PERIOD WITH SLIGHT CHANCE TO CHANCE POPS ACROSS
THE BOARD. IN ADDITION...MODELS CONTINUE AT LEASE A SLIGHT CHANCE
THROUGH TONIGHT. ALSO...HPC QPF GRIDS FOR THE FIRST 24 HOURS LOOK
REASONABLE.

AS FOR TEMPERATURES...NUMBERS CLOSE TO MEX MOS LOOK ON TRACK FOR
TODAY AND TONIGHT. LIMITED SUNSHINE AND NORTHWEST FLOW ALOFT WILL
HOLD AFTERNOON HIGHS TODAY MAINLY IN THE LOWER TO MID 90S. OVERNIGHT
LOWS TONIGHT WILL BE MAINLY IN THE LOWER TO MID 70S.

HUBER

LONG TERM...
BY SATURDAY MORNING THE MID LEVEL TROUGH AXIS WILL STRETCH
NORTHEASTWARD FROM SOUTHERN NEW MEXICO ACROSS THE NORTHERN
PANHANDLE AND INTO THE CENTRAL PLAINS. THE SLOW MOVING UPPER
TROUGH AXIS WILL FINALLY MOVE EAST OF THE FORECAST AREA BY LATE
SUNDAY. UNTIL THEN...ISOLATED TO SCATTERED THUNDERSTORMS WILL BE
POSSIBLE OVER MUCH OF THE FORECAST AREA...FAVORING THE WESTERN AND
NORTHERN CWA.

WITH AN INCREASE IN CLOUD COVER...AFTERNOON HIGHS WILL REMAIN IN
THE LOW TO MID 90S THROUGH THE WEEKEND. MORNING LOWS WILL BE IN
THE LOWER 70S.

UPPER LEVEL HILL PRESSURE WILL BUILD INTO THE AREA IN THE WAKE OF
THE DEPARTING UPPER LEVEL TROUGH INTO THE FIRST OF THE COMING
WEEK. THE CENTER OF THE UPPER LEVEL HIGH WILL SETTLE OVER NEW
MEXICO. WITH THE UPPER RIDGE AND SUNNY SKIES DOMINATING THE AREA
AT LEAST THROUGH THE MIDDLE OF NEXT WEEK...AFTERNOON TEMPERATURES
WILL EDGE A LITTLE HIGHER TO THE MID TO UPPER 90S. LOOKING FOR A
DRY FORECAST FOR THE REMAINDER OF THE EXTENDED.

&&

.PRELIMINARY POINT TEMPS/POPS...
ABILENE  73  95  73  94  72 /  20  20  20  20  20
SAN ANGELO  73  95  73  95  72 /  20  20  20  10  10
JUNCTION  74  92  71  93  70 /  10  10  10  10  10

&&

.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

HUBER






AREA FORECAST DISCUSSION

NWS SAN ANGELO TX

 328 AM CDT FRI AUG 24 2012

.SHORT TERM...
RAIN CHANCES FOR MOST OF WEST CENTRAL TEXAS LOOK SOMEWHAT PROMISING
FOR THE NEXT 24 HOURS. MODELS INDICATE A SHORT WAVE TROUGH OF LOW
PRESSURE WILL PROVIDE SOME UPPER-LEVEL DYNAMICS. MODELS SHOW THIS
FEATURE BEST AT 700 MB. ALTHOUGH THE NAM AND THE RUC (HIGH
RESOLUTION RAPID REFRESH) INDICATE SOME DECLINE IN CONVECTIVE
COVERAGE BETWEEN NOW AND 18Z...I DECIDED TO INCLUDE THE FIRST 6
HOURS OF THE TODAY PERIOD WITH SLIGHT CHANCE TO CHANCE POPS ACROSS
THE BOARD. IN ADDITION...MODELS CONTINUE AT LEASE A SLIGHT CHANCE
THROUGH TONIGHT. ALSO...HPC QPF GRIDS FOR THE FIRST 24 HOURS LOOK
REASONABLE.

AS FOR TEMPERATURES...NUMBERS CLOSE TO MEX MOS LOOK ON TRACK FOR
TODAY AND TONIGHT. LIMITED SUNSHINE AND NORTHWEST FLOW ALOFT WILL
HOLD AFTERNOON HIGHS TODAY MAINLY IN THE LOWER TO MID 90S. OVERNIGHT
LOWS TONIGHT WILL BE MAINLY IN THE LOWER TO MID 70S.

HUBER

.LONG TERM...
BY SATURDAY MORNING THE MID LEVEL TROUGH AXIS WILL STRETCH
NORTHEASTWARD FROM SOUTHERN NEW MEXICO ACROSS THE NORTHERN
PANHANDLE AND INTO THE CENTRAL PLAINS. THE SLOW MOVING UPPER
TROUGH AXIS WILL FINALLY MOVE EAST OF THE FORECAST AREA BY LATE
SUNDAY. UNTIL THEN...ISOLATED TO SCATTERED THUNDERSTORMS WILL BE
POSSIBLE OVER MUCH OF THE FORECAST AREA...FAVORING THE WESTERN AND
NORTHERN CWA.

WITH AN INCREASE IN CLOUD COVER...AFTERNOON HIGHS WILL REMAIN IN
THE LOW TO MID 90S THROUGH THE WEEKEND. MORNING LOWS WILL BE IN
THE LOWER 70S.

UPPER LEVEL HILL PRESSURE WILL BUILD INTO THE AREA IN THE WAKE OF
THE DEPARTING UPPER LEVEL TROUGH INTO THE FIRST OF THE COMING
WEEK. THE CENTER OF THE UPPER LEVEL HIGH WILL SETTLE OVER NEW
MEXICO. WITH THE UPPER RIDGE AND SUNNY SKIES DOMINATING THE AREA
AT LEAST THROUGH THE MIDDLE OF NEXT WEEK...AFTERNOON TEMPERATURES
WILL EDGE A LITTLE HIGHER TO THE MID TO UPPER 90S. LOOKING FOR A
DRY FORECAST FOR THE REMAINDER OF THE EXTENDED.

&&

.PRELIMINARY POINT TEMPS/POPS...
ABILENE  93  73  95  73  94 /  30  20  20  20  20
SAN ANGELO  94  73  95  73  95 /  20  20  20  20  10
JUNCTION  93  74  92  71  93 /  20  10  10  10  10

&&

.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

15






AREA FORECAST DISCUSSION

NWS LUBBOCK TX

 1150 PM CDT THU AUG 23 2012

.AVIATION...
VFR WITH AN INCREASING COVERAGE OF SHRA AND SOME TSRA EARLY THIS
NIGHT. OUTFLOW BOUNDARY FROM STORMS HAS JUST PUSHED ACROSS LBB
WITH GUSTY WESTERLY WINDS...ALTHOUGH NEGATIVE IMPACTS BEYOND THIS
ARE NOT IN THE OFFING AS STORMS HAVE MINIMAL INSTABILITY TO WORK
WITH FOR STRONG OR SEVERE WEATHER. REDUCED COVERAGE OF STORMS
DEVELOPING WEST OF CDS APPEARS BEST HANDLED WITH A TEMPO THROUGH
09Z. ADDITIONAL PRECIP WILL SPREAD NORTHEAST FROM SERN NM THROUGH
THE PRE-DAWN HOURS...BUT A GENERAL DECAYING TREND IS EXPECTED.
CEILINGS COULD LOWER TO LOW VFR LEVELS AT THE TERMINALS ESPECIALLY
IN THE WAKE OF THE PRECIPITATION. SOME CLEARING FRI AFTN SHOULD
YIELD ANOTHER CHANCE OF TSRA AHEAD OF A DEVELOPING DRYLINE AND
STRONG UPPER TROUGH FOR AUGUST STANDARDS. INITIAL INSPECTION OF
NEW MODEL DATA SUGGESTS POTENTIAL FOR SOME SEVERE TSRA...BUT
LATER SHIFTS WILL INVESTIGATE THIS THREAT IN MORE DETAIL.

&&

.PREV DISCUSSION... /ISSUED 929 PM CDT THU AUG 23 2012/

UPDATE...
LARGE BUT LOOSELY ORGANIZED LINE OF SHOWERS AND STORMS WAS FOUND
STRETCHING FROM DALHART SOUTH TO THE UPPER RIO GRANDE LATE THIS
EVENING IN ADVANCE OF AN UPPER TROUGH CURRENTLY IN CENTRAL NEW
MEXICO. RECENT IR SATELLITE IMAGERY CONFIRMS A DECAYING PROCESS
UNDERWAY WITH THE CONVECTION OVER THE MIDDLE EXTENT OF THE LINE
/ROUGHLY NEAR CLOVIS/ WITH RENEWED DEVELOPMENT FARTHER SOUTH FROM
EASTERN LEA COUNTY INTO THE FAR SOUTHWEST SOUTH PLAINS ATTENDANT
WITH AN APPARENT MCV PER REGIONAL 88D DATA. ALTHOUGH MINIMAL CAPE
WILL GOVERN THE REMAINDER OF THE OVERNIGHT...STEADY LIFT AND
SLIGHTLY DEEPER MOISTURE IN ADVANCE OF THIS CONVECTION SHOULD
SUSTAIN ISOLATED TO SCATTERED STORMS OVER THE REMAINDER OF THE
SOUTH PLAINS AS THIS ACTIVITY CONTINUES STEADILY EAST. BUMPED POPS
UP ACCORDINGLY THROUGH 06Z WITH REDUCED VALUES THEREAFTER AS
CONVECTION SLOWLY WANES AND OUTRUNS THE UPPER SUPPORT. RECENT RUNS
OF THE HRRR ARE PERFORMING REASONABLY WELL IN DEPICTING THE
AFOREMENTIONED DECAYING TREND NEAR CLOVIS WITH PREFERRED
DEVELOPMENT FARTHER SOUTH.

&&

.PRELIMINARY POINT TEMPS/POPS...
FRIONA        64  88  64  90  64 /  60  20  20  20  20
TULIA         66  87  66  90  65 /  50  20  30  20  30
PLAINVIEW     67  86  66  90  66 /  50  20  30  20  30
LEVELLAND     66  86  67  93  67 /  60  20  20  20  20
LUBBOCK       69  89  68  93  68 /  50  20  20  20  20
DENVER CITY   64  87  68  94  67 /  60  20  20  20  20
BROWNFIELD    64  87  67  94  68 /  60  20  20  20  20
CHILDRESS     70  88  70  94  70 /  30  30  30  20  30
SPUR          68  89  69  93  70 /  30  30  30  20  20
ASPERMONT     71  90  72  96  72 /  30  30  30  20  20

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

93






AREA FORECAST DISCUSSION

NWS FORT WORTH TX

 1134 PM CDT THU AUG 23 2012

.AVIATION...
AN UPPER LOW CAN BE SEEN SPINNING OVER THE FOUR CORNERS REGION
THIS EVENING ON THE LATEST SATELLITE LOOP. THE SYSTEM IS FORECAST
TO WORK ITS WAY EAST INTO THE PLAINS BEFORE OPENING UP AND
WEAKENING LATE IN THE WEEKEND. UNTIL THEN...LOW LEVEL MOISTURE
WILL GRADUALLY INCREASE ACROSS NORTH TEXAS OVER THE NEXT 48 HOURS
AHEAD OF THIS FEATURE. THUNDERSTORMS ARE EXPECTED TO DEVELOP A BIT
CLOSER TO THE AREA FRIDAY AFTERNOON AND EVENING AS THE UPPER LOW
APPROACHES THE TX/NM BORDER. IT STILL LOOKS LIKE THE BEST CHANCE
FOR CONVECTION WILL BE NORTHWEST OF TAF SITES...SO WILL NOT
MENTION IN THE LOCAL TAFS AT THIS TIME. HOWEVER...WILL NEED TO
KEEP AN EYE ON FUTURE GUIDANCE AND TRENDS FRIDAY AFTERNOON.

SURFACE WINDS HAVE DISPLAYED MORE OF AN EAST COMPONENT THAN THE
PAST SEVERAL MODEL RUNS HAVE SHOWN AND BELIEVE THIS COULD CONTINUE
FOR ANOTHER DAY. SPEEDS OF AROUND 10 KTS WILL REMAIN IN THE
FORECAST THROUGH FRIDAY NIGHT. SLIGHTLY HIGHER SPEEDS ARE LIKELY
ON SATURDAY AS THE GRADIENT TIGHTENS A BIT MORE.  OTHERWISE...WILL
KEEP THE TEMPO MVFR DECK IN AT ALL SITES FOR FRIDAY MORNING AND
INTRODUCE THE RETURN OF MVFR STRATUS IN THE EXTENDED DFW TAF.

30

&&



.PREV DISCUSSION... /ISSUED 302 PM CDT THU AUG 23 2012/
CONVECTION FROM CHILDRESS TO SNYDER REMAINS WELL ELEVATED...WITH
BASES AOA 10KFT AGL. AS THE ACTIVITY MOVES EAST...IT WILL ENTER
AN AREA OF DEEPER MID-LEVEL MOISTURE. AS THE STORMS INGEST THIS
AIR...THE DCAPE (IN A LAGRANGIAN SENSE) WILL DIMINISH
CONSIDERABLY...AND THE THREAT OF DOWNBURST WINDS WILL BE
NEGLIGIBLE...DESPITE THE HIGH BASES. WITH WEAK SHEAR AND MOIST
ADIABATIC LAPSE RATES ALOFT...THE CONVECTION IS UNLIKELY TO
INTENSIFY...BUT IT MAY HOLD TOGETHER LONG ENOUGH TO REACH FAR
WESTERN ZONES LATE THIS AFTERNOON OR EARLY EVENING BEFORE
DISSIPATING. THE CU FIELD JUST WEST OF THE CWA IS BASED AROUND
5KFT AND APPEARS TO BE CAPPED...BUT WITH ANY FORCING ABOVE
800MB...THE MINIMAL INHIBITION CURRENTLY IN PLACE SHOULD BE ERODED
SUFFICIENTLY TO ALLOW SOME CELLS TO BECOME SURFACE-BASED.
REGARDLESS...THE BOUNDARY-LAYER INSTABILITY IS UNIMPRESSIVE...AND
ENTRAINING THIS SURFACE AIR WOULD ONLY FURTHER DECREASE THE
DOWNBURST THREAT.

SEA BREEZE CONVECTION IS CURRENTLY CONFINED TO THE HOUSTON METRO
AREA. AS SUCH...CONFIDENCE IS DIMINISHING FURTHER IN THE POTENTIAL
FOR ANY PROPAGATING OUTFLOW BOUNDARIES REACHING THE CWA. AS WITH
PREVIOUS RUNS...THE 18Z RUC MAINTAINS SOME CONVECTIVE CELLS IN FAR
SOUTHEAST ZONES...WHERE THE PROFILE WILL BECOME INCREASINGLY
TROPICAL. WITH DEEPENING MOISTURE AND DIMINISHING SUBSIDENCE...
WILL CONTINUE TO CARRY SOME ISOLATED MENTION IN THE SOUTHEAST.

LAS VEGAS HAD TALLIED ONLY 1.53 INCHES OF PRECIP IN 11 MONTHS
BEFORE RECEIVING A DELUGE OF 1.65 INCHES ON WEDNESDAY. (THIS
EASILY BROKE THE DAILY RECORD OF 0.23 INCHES.) THE OFFENDING
SHORTWAVE CONTINUES TO DEEPEN OVER THE FOUR CORNERS...WITH
WIDESPREAD CONVECTION DOWNSTREAM ACROSS NEW MEXICO AND COLORADO.
AS THE SYSTEM REACHES THE TEXAS PANHANDLE...IT WILL BE IN PHASE
WITH THE CYCLONE NEAR THE CANADIAN BORDER. AS A RESULT...THE
FEATURE WILL LIKELY SHEAR AND BE DRAWN NORTHWARD. WITH THE ENERGY
FARTHER NORTH...THE PRECIPITATION CHANCES FOR NORTH TEXAS THIS
WEEKEND WOULD BE REDUCED. WILL MAINTAIN BEST CHANCES GENERALLY
ALONG THE RED RIVER VALLEY. DESPITE THE LIKELY EVOLUTION OF THE
CONVECTIVE EVENT...EXTENDED GUIDANCE IS STILL FAVORING A RESULTING
EROSION OF THE RIDGE ABOVE NORTH TEXAS.

THE SHORTWAVE (AND MUCH LARGER CYCLONE) WILL ALLOW MILDER AIR TO
INVADE THE CENTRAL PLAINS. BUT WITH NEAR NORMAL TEMPERATURES
EXPECTED WITH THE SURFACE ANTICYCLONE...IT WOULD SUGGEST A
TENDENCY FOR THE ASSOCIATED FRONTAL BOUNDARY TO FAIL TO PENETRATE
THE SOUTHERN PLAINS. BUT IF THE RIDGE DOES ERODE ENOUGH TO ALLOW
FOR NORTHERLY FLOW...THE BOUNDARY COULD CERTAINLY REACH NORTH
TEXAS. EVEN THE ECMWF...WHICH PROJECTS A MID-LEVEL RIDGE AXIS FROM
TEXAS INTO THE PRAIRIE PROVINCES EARLY NEXT WEEK...ALLOWS
NORTHERLY SURFACE FLOW TO SLIDE DOWN THE MISSISSIPPI VALLEY AND
BACKDOOR INTO NORTH TEXAS...INDUCED BY THE PROXIMITY OF ISAAC.
(THE LATEST ECMWF RUN TAKES ISAAC INTO DFW...BUT THE EURO WAS
ALREADY A FAR WESTERN OUTLIER...SO DO NOT HAVE MUCH CONFIDENCE IN
THIS LATEST SOLUTION.) EXPECT A WARMING TREND NEXT WEEK...DESPITE
ANY LIGHT NORTH WINDS. WHATEVER TRACK ISAAC TAKES...NORTH TEXAS
WOULD LIKELY BE IN A SUBSIDENT ZONE. A MORE EASTERLY TRACK WOULD
ALLOW THE PLAINS RIDGE TO INTENSIFY...WHILE A MORE WESTERLY TRACK
COULD PUT EAST TEXAS WITHIN THE RING OF STRONG DOWNWARD MOTION
AROUND THE PERIPHERY OF THE CIRRUS SHIELD. TEMPERATURES MAY REACH
THE UPPER 90S BY DAY 7 (THURSDAY AUGUST 30).

25



&&


.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX  76  93  76  94  77 /   5  10  20  20  20
WACO, TX              74  94  75  94  76 /   5  10  10  10  10
PARIS, TX             70  91  71  91  73 /   5  20  30  50  20
DENTON, TX            73  93  75  94  76 /   5  10  20  20  20
MCKINNEY, TX          70  91  73  91  75 /   5  20  20  30  20
DALLAS, TX            75  91  76  94  77 /   5  10  20  20  20
TERRELL, TX           72  91  73  92  75 /   5  20  20  20  20
CORSICANA, TX         73  92  73  93  75 /   5  10  20  20  10
TEMPLE, TX            73  94  73  94  74 /  10  10  10  10  10
MINERAL WELLS, TX     72  94  72  94  73 /   5  10  20  20  20

&&

.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

30/






AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 1239 PM CDT FRI AUG 24 2012

.SHORT TERM...THROUGH SUNDAY
239 AM CDT FRI AUG 24 2012

MAIN FORECAST CONCERN IS WITH THE RAIN CHANCES THROUGH THE PERIOD.

SURFACE ANALYSIS THIS MORNING SHOWS AN AREA OF LOW PRESSURE OVER
SOUTHEAST MONTANA. A WEAK WARM FRONT EXTENDS FROM THE LOW ACROSS
CENTRAL MINNESOTA INTO NORTHERN WISCONSIN. REGIONAL RADARS WERE
SHOWING A LINE OF SHOWERS AND THUNDERSTORMS FROM LAKE SUPERIOR
INTO NORTHEAST IOWA.

THE ONGOING CONVECTION WAS BEING FUELED BY A SHORT WAVE TROUGH
MOVING ACROSS MINNESOTA. THE 24.05Z RAP INDICATES THIS WAVE WILL
MOVE EAST INTO WISCONSIN IN THE PRE-DAWN HOURS AND THEN AWAY FROM
THE REGION AFTER SUNRISE. THE ACTIVITY CURRENTLY LOOKS TO BE ON
THE EASTERN EDGE OF THE MU CAPE GRADIENT AS THIS QUICKLY DROPS TO
250 J/KG OR LESS ACROSS WESTERN INTO CENTRAL WISCONSIN. BOTH THE
24.00Z HIRES ARW AND NMM SUGGEST THE ACTIVITY IS THE STRONGEST NOW
AND WILL DISSIPATE THROUGH THE REMAINDER OF THE NIGHT AS IT MOVES
OUT OF THE CAPE AXIS. WILL MONITOR THE LATEST RADAR TRENDS AND
MAKE ADJUSTMENTS AS NEEDED BUT CURRENTLY FEEL THE BEST CHANCE OF
ANY ACTIVITY STILL TO BE ONGOING AFTER 12Z IS ACROSS NORTH CENTRAL
WISCONSIN WHERE THE CAPE IS A LITTLE BETTER AND THE MOISTURE
TRANSPORT SHOULD BE THE STRONGEST. FOR THE AFTERNOON...THE 24.00Z
NAM AND GFS INDICATE ANOTHER WEAK SHORT WAVE TROUGH WILL TRACK
ACROSS NORTHERN MINNESOTA TOWARD LAKE SUPERIOR. THIS WAVE WILL
PRODUCE ONLY SOME WEAK VORTICITY ADVECTION IN THE 500-300 MB LAYER
NORTH OF THE AREA. SOME WEAK ISENTROPIC UP GLIDE WILL CONTINUE
OVER THE REMAINS OF THE WARM FRONT WITH THE NAM SHOWING AROUND 2
UBAR/S ACROSS NORTHWEST INTO CENTRAL WISCONSIN. THIS MAY BE ENOUGH
TO GENERATE SOME ADDITIONAL WIDELY SCATTERED CONVECTION AND WILL
KEEP THE 20 PERCENT CHANCES IN THE I94 CORRIDOR.

AFTER TODAY...THE NEXT CHANCE OF RAIN WILL BE SATURDAY THROUGH
SUNDAY. A LARGE UPPER LEVEL LOW OVER WESTERN CANADA WILL TRACK
EAST WHILE REMAINING NORTH OF THE BORDER. AS IT DOES...A WEAK
UPPER LEVEL LOW OVER THE FOUR CORNERS WILL CONTINUE TO WEAKEN AND
BECOME AN OPEN WAVE WHILE BEING PULLED NORTHEAST AHEAD OF THE
CANADIAN UPPER LEVEL LOW. THE MODELS INDICATE THE REMAINS OF THE
FOUR CORNERS UPPER LEVEL LOW WILL COME THROUGH IN A COUPLE OF
PIECES WITH THE FIRST MOVING ACROSS THE REGION SATURDAY AND THE
SECOND SATURDAY NIGHT AND SUNDAY. NONE OF THE MODELS PRODUCE MUCH
VORTICITY ADVECTION WITH THE NAM AND 23.12Z ECMWF SHOWING 2 PVU/S
OR LESS WHILE THE 24.00Z GFS IS A LITTLE STRONGER SHOWING UP TO 4
PVU/S. A WEAK COLD FRONT OR TROUGH OF LOW PRESSURE SHOULD MOVE
SLOWLY ACROSS THE AREA WITH THE SHORT WAVE TROUGHS. SOME WEAK
FRONTOGENESIS IN THE 1000-700 MB LAYER SHOULD OCCUR WITH THIS
FEATURE SATURDAY AFTERNOON AND THERE SHOULD BE SOME PERSISTENT UP
GLIDE OF 1 TO 3 UBAR/S ON THE 310K SURFACE UNTIL THIS FEATURE
MOVES THROUGH THE AREA. SINCE THE FORCING WITH THESE WAVES IS NOT
THAT STRONG EXPECTING MAINLY SCATTERED CONVECTION TO OCCUR
SATURDAY AS THE LEAD WAVE COMES IN. THE COVERAGE COULD BE A LITTLE
BIT BETTER SATURDAY NIGHT ACROSS THE SOUTH AHEAD OF THE SECOND
WAVE WHERE THE VORTICITY ADVECTION COULD BE A LITTLE BIT STRONGER.
THE SEVERE POTENTIAL LOOKS PRETTY LOW SATURDAY AND SATURDAY NIGHT
WITH ML CAPES OF 500 J/KG OR LESS EXPECTED AND THE 0-6 KM SHEAR IS
ONLY AROUND 25 KNOTS.

.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
239 AM CDT FRI AUG 24 2012

ONCE THIS SYSTEMS MOVES OUT...A LARGE AREA OF HIGH PRESSURE WILL
BUILD IN OVER THE UPPER MIDWEST AND SHOULD REMAIN THROUGH MUCH OF
THE PERIOD. TOWARD THE END OF THE PERIOD...THE GFS IS TRYING TO
BRING A SHORT WAVE TROUGH AND UPPER LEVEL LOW THROUGH THE TOP OF
THE UPPER LEVEL RIDGE AND ACROSS SOUTHERN CANADA AND THE UPPER
MIDWEST. THE 24.00Z ECMWF MAINTAINS THE UPPER LEVEL RIDGE OVER THE
AREA WITH ANY TROUGHING OVER SOUTHWEST CANADA INTO THE NORTHERN
ROCKIES. WILL TREND TOWARD THE ECMWF SOLUTION AND KEEP THE ENTIRE
PERIOD DRY.

&&

.AVIATION...THROUGH 18Z SATURDAY
1239 PM CDT FRI AUG 24 2012

THE MAIN FOCUS INTO TOMORROW COMES WITH THE CHANCES FOR SHOWERS
AND THUNDERSTORMS LATE THIS AFTERNOON AND TOMORROW MORNING.
A FEW SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS
AFTERNOON BUT WILL LIKELY FORM TO THE NORTH OF THE TAF SITES. A
MID LEVEL CLOUD DECK SHOULD TRACK TO THE NORTH AS WELL WITH SKIES
CLEARING OUT TO THE SOUTH. WINDS WILL LIGHTEN UP OVERNIGHT AS WELL
BEFORE MORE MID LEVEL CLOUDS MOVE BACK IN BEFORE DAY BREAK. THE
NEXT STORM SYSTEM THEN MOVES IN FROM THE WEST TOMORROW MORNING
WITH SHOWERS AND THUNDERSTORMS GETTING NEAR RST BY LATE MORNING.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
239 AM CDT FRI AUG 24 2012

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

&&

$$

SHORT TERM...04
LONG TERM...04
AVIATION...HALBACH







AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 634 AM CDT FRI AUG 24 2012

.SHORT TERM...THROUGH SUNDAY
239 AM CDT FRI AUG 24 2012

MAIN FORECAST CONCERN IS WITH THE RAIN CHANCES THROUGH THE PERIOD.

SURFACE ANALYSIS THIS MORNING SHOWS AN AREA OF LOW PRESSURE OVER
SOUTHEAST MONTANA. A WEAK WARM FRONT EXTENDS FROM THE LOW ACROSS
CENTRAL MINNESOTA INTO NORTHERN WISCONSIN. REGIONAL RADARS WERE
SHOWING A LINE OF SHOWERS AND THUNDERSTORMS FROM LAKE SUPERIOR
INTO NORTHEAST IOWA.

THE ONGOING CONVECTION WAS BEING FUELED BY A SHORT WAVE TROUGH
MOVING ACROSS MINNESOTA. THE 24.05Z RAP INDICATES THIS WAVE WILL
MOVE EAST INTO WISCONSIN IN THE PRE-DAWN HOURS AND THEN AWAY FROM
THE REGION AFTER SUNRISE. THE ACTIVITY CURRENTLY LOOKS TO BE ON
THE EASTERN EDGE OF THE MU CAPE GRADIENT AS THIS QUICKLY DROPS TO
250 J/KG OR LESS ACROSS WESTERN INTO CENTRAL WISCONSIN. BOTH THE
24.00Z HIRES ARW AND NMM SUGGEST THE ACTIVITY IS THE STRONGEST NOW
AND WILL DISSIPATE THROUGH THE REMAINDER OF THE NIGHT AS IT MOVES
OUT OF THE CAPE AXIS. WILL MONITOR THE LATEST RADAR TRENDS AND
MAKE ADJUSTMENTS AS NEEDED BUT CURRENTLY FEEL THE BEST CHANCE OF
ANY ACTIVITY STILL TO BE ONGOING AFTER 12Z IS ACROSS NORTH CENTRAL
WISCONSIN WHERE THE CAPE IS A LITTLE BETTER AND THE MOISTURE
TRANSPORT SHOULD BE THE STRONGEST. FOR THE AFTERNOON...THE 24.00Z
NAM AND GFS INDICATE ANOTHER WEAK SHORT WAVE TROUGH WILL TRACK
ACROSS NORTHERN MINNESOTA TOWARD LAKE SUPERIOR. THIS WAVE WILL
PRODUCE ONLY SOME WEAK VORTICITY ADVECTION IN THE 500-300 MB LAYER
NORTH OF THE AREA. SOME WEAK ISENTROPIC UP GLIDE WILL CONTINUE
OVER THE REMAINS OF THE WARM FRONT WITH THE NAM SHOWING AROUND 2
UBAR/S ACROSS NORTHWEST INTO CENTRAL WISCONSIN. THIS MAY BE ENOUGH
TO GENERATE SOME ADDITIONAL WIDELY SCATTERED CONVECTION AND WILL
KEEP THE 20 PERCENT CHANCES IN THE I94 CORRIDOR.

AFTER TODAY...THE NEXT CHANCE OF RAIN WILL BE SATURDAY THROUGH
SUNDAY. A LARGE UPPER LEVEL LOW OVER WESTERN CANADA WILL TRACK
EAST WHILE REMAINING NORTH OF THE BORDER. AS IT DOES...A WEAK
UPPER LEVEL LOW OVER THE FOUR CORNERS WILL CONTINUE TO WEAKEN AND
BECOME AN OPEN WAVE WHILE BEING PULLED NORTHEAST AHEAD OF THE
CANADIAN UPPER LEVEL LOW. THE MODELS INDICATE THE REMAINS OF THE
FOUR CORNERS UPPER LEVEL LOW WILL COME THROUGH IN A COUPLE OF
PIECES WITH THE FIRST MOVING ACROSS THE REGION SATURDAY AND THE
SECOND SATURDAY NIGHT AND SUNDAY. NONE OF THE MODELS PRODUCE MUCH
VORTICITY ADVECTION WITH THE NAM AND 23.12Z ECMWF SHOWING 2 PVU/S
OR LESS WHILE THE 24.00Z GFS IS A LITTLE STRONGER SHOWING UP TO 4
PVU/S. A WEAK COLD FRONT OR TROUGH OF LOW PRESSURE SHOULD MOVE
SLOWLY ACROSS THE AREA WITH THE SHORT WAVE TROUGHS. SOME WEAK
FRONTOGENESIS IN THE 1000-700 MB LAYER SHOULD OCCUR WITH THIS
FEATURE SATURDAY AFTERNOON AND THERE SHOULD BE SOME PERSISTENT UP
GLIDE OF 1 TO 3 UBAR/S ON THE 310K SURFACE UNTIL THIS FEATURE
MOVES THROUGH THE AREA. SINCE THE FORCING WITH THESE WAVES IS NOT
THAT STRONG EXPECTING MAINLY SCATTERED CONVECTION TO OCCUR
SATURDAY AS THE LEAD WAVE COMES IN. THE COVERAGE COULD BE A LITTLE
BIT BETTER SATURDAY NIGHT ACROSS THE SOUTH AHEAD OF THE SECOND
WAVE WHERE THE VORTICITY ADVECTION COULD BE A LITTLE BIT STRONGER.
THE SEVERE POTENTIAL LOOKS PRETTY LOW SATURDAY AND SATURDAY NIGHT
WITH ML CAPES OF 500 J/KG OR LESS EXPECTED AND THE 0-6 KM SHEAR IS
ONLY AROUND 25 KNOTS.

.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
239 AM CDT FRI AUG 24 2012

ONCE THIS SYSTEMS MOVES OUT...A LARGE AREA OF HIGH PRESSURE WILL
BUILD IN OVER THE UPPER MIDWEST AND SHOULD REMAIN THROUGH MUCH OF
THE PERIOD. TOWARD THE END OF THE PERIOD...THE GFS IS TRYING TO
BRING A SHORT WAVE TROUGH AND UPPER LEVEL LOW THROUGH THE TOP OF
THE UPPER LEVEL RIDGE AND ACROSS SOUTHERN CANADA AND THE UPPER
MIDWEST. THE 24.00Z ECMWF MAINTAINS THE UPPER LEVEL RIDGE OVER THE
AREA WITH ANY TROUGHING OVER SOUTHWEST CANADA INTO THE NORTHERN
ROCKIES. WILL TREND TOWARD THE ECMWF SOLUTION AND KEEP THE ENTIRE
PERIOD DRY.

&&

.AVIATION...TODAY AND TONIGHT
633 AM CDT FRI AUG 24 2012

A SHORT WAVE TROUGH CONTINUES TO PRODUCE A BAND OF SHOWERS AND
THUNDERSTORMS SOUTHEAST OF A CHARLES CITY IOWA TO JUMP RIVER
WISCONSIN LINE. THIS PRECIPITATION WILL MOVE OUT OF KLSE BY
24.13Z. A FEW MORE SHOWERS AND THUNDERSTORMS MAY DEVELOP ALONG AND
NORTH OF THE INTERSTATE 90 CORRIDOR IN WISCONSIN THIS AFTERNOON.
HOWEVER THE CONFIDENCE IS SO SMALL THAT THEY WERE NOT INCLUDED IN
THE KLSE TAF.

FOR TONIGHT...BOTH TAF SITES WILL BE WELL INTO THE WARM SECTOR OF
AN APPROACHING LOW PRESSURE SYSTEM FROM THE NORTHERN PLAINS. AS A
RESULT...SKIES SHOULD BE MAINLY CLEAR.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
239 AM CDT FRI AUG 24 2012

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

&&

$$

SHORT TERM...04
LONG TERM...04
AVIATION...BOYNE







AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 240 AM CDT FRI AUG 24 2012

.SHORT TERM...THROUGH SUNDAY
239 AM CDT FRI AUG 24 2012

MAIN FORECAST CONCERN IS WITH THE RAIN CHANCES THROUGH THE PERIOD.

SURFACE ANALYSIS THIS MORNING SHOWS AN AREA OF LOW PRESSURE OVER
SOUTHEAST MONTANA. A WEAK WARM FRONT EXTENDS FROM THE LOW ACROSS
CENTRAL MINNESOTA INTO NORTHERN WISCONSIN. REGIONAL RADARS WERE
SHOWING A LINE OF SHOWERS AND THUNDERSTORMS FROM LAKE SUPERIOR
INTO NORTHEAST IOWA.

THE ONGOING CONVECTION WAS BEING FUELED BY A SHORT WAVE TROUGH
MOVING ACROSS MINNESOTA. THE 24.05Z RAP INDICATES THIS WAVE WILL
MOVE EAST INTO WISCONSIN IN THE PRE-DAWN HOURS AND THEN AWAY FROM
THE REGION AFTER SUNRISE. THE ACTIVITY CURRENTLY LOOKS TO BE ON
THE EASTERN EDGE OF THE MU CAPE GRADIENT AS THIS QUICKLY DROPS TO
250 J/KG OR LESS ACROSS WESTERN INTO CENTRAL WISCONSIN. BOTH THE
24.00Z HIRES ARW AND NMM SUGGEST THE ACTIVITY IS THE STRONGEST NOW
AND WILL DISSIPATE THROUGH THE REMAINDER OF THE NIGHT AS IT MOVES
OUT OF THE CAPE AXIS. WILL MONITOR THE LATEST RADAR TRENDS AND
MAKE ADJUSTMENTS AS NEEDED BUT CURRENTLY FEEL THE BEST CHANCE OF
ANY ACTIVITY STILL TO BE ONGOING AFTER 12Z IS ACROSS NORTH CENTRAL
WISCONSIN WHERE THE CAPE IS A LITTLE BETTER AND THE MOISTURE
TRANSPORT SHOULD BE THE STRONGEST. FOR THE AFTERNOON...THE 24.00Z
NAM AND GFS INDICATE ANOTHER WEAK SHORT WAVE TROUGH WILL TRACK
ACROSS NORTHERN MINNESOTA TOWARD LAKE SUPERIOR. THIS WAVE WILL
PRODUCE ONLY SOME WEAK VORTICITY ADVECTION IN THE 500-300 MB LAYER
NORTH OF THE AREA. SOME WEAK ISENTROPIC UP GLIDE WILL CONTINUE
OVER THE REMAINS OF THE WARM FRONT WITH THE NAM SHOWING AROUND 2
UBAR/S ACROSS NORTHWEST INTO CENTRAL WISCONSIN. THIS MAY BE ENOUGH
TO GENERATE SOME ADDITIONAL WIDELY SCATTERED CONVECTION AND WILL
KEEP THE 20 PERCENT CHANCES IN THE I94 CORRIDOR.

AFTER TODAY...THE NEXT CHANCE OF RAIN WILL BE SATURDAY THROUGH
SUNDAY. A LARGE UPPER LEVEL LOW OVER WESTERN CANADA WILL TRACK
EAST WHILE REMAINING NORTH OF THE BORDER. AS IT DOES...A WEAK
UPPER LEVEL LOW OVER THE FOUR CORNERS WILL CONTINUE TO WEAKEN AND
BECOME AN OPEN WAVE WHILE BEING PULLED NORTHEAST AHEAD OF THE
CANADIAN UPPER LEVEL LOW. THE MODELS INDICATE THE REMAINS OF THE
FOUR CORNERS UPPER LEVEL LOW WILL COME THROUGH IN A COUPLE OF
PIECES WITH THE FIRST MOVING ACROSS THE REGION SATURDAY AND THE
SECOND SATURDAY NIGHT AND SUNDAY. NONE OF THE MODELS PRODUCE MUCH
VORTICITY ADVECTION WITH THE NAM AND 23.12Z ECMWF SHOWING 2 PVU/S
OR LESS WHILE THE 24.00Z GFS IS A LITTLE STRONGER SHOWING UP TO 4
PVU/S. A WEAK COLD FRONT OR TROUGH OF LOW PRESSURE SHOULD MOVE
SLOWLY ACROSS THE AREA WITH THE SHORT WAVE TROUGHS. SOME WEAK
FRONTOGENESIS IN THE 1000-700 MB LAYER SHOULD OCCUR WITH THIS
FEATURE SATURDAY AFTERNOON AND THERE SHOULD BE SOME PERSISTENT UP
GLIDE OF 1 TO 3 UBAR/S ON THE 310K SURFACE UNTIL THIS FEATURE
MOVES THROUGH THE AREA. SINCE THE FORCING WITH THESE WAVES IS NOT
THAT STRONG EXPECTING MAINLY SCATTERED CONVECTION TO OCCUR
SATURDAY AS THE LEAD WAVE COMES IN. THE COVERAGE COULD BE A LITTLE
BIT BETTER SATURDAY NIGHT ACROSS THE SOUTH AHEAD OF THE SECOND
WAVE WHERE THE VORTICITY ADVECTION COULD BE A LITTLE BIT STRONGER.
THE SEVERE POTENTIAL LOOKS PRETTY LOW SATURDAY AND SATURDAY NIGHT
WITH ML CAPES OF 500 J/KG OR LESS EXPECTED AND THE 0-6 KM SHEAR IS
ONLY AROUND 25 KNOTS.

.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
239 AM CDT FRI AUG 24 2012

ONCE THIS SYSTEMS MOVES OUT...A LARGE AREA OF HIGH PRESSURE WILL
BUILD IN OVER THE UPPER MIDWEST AND SHOULD REMAIN THROUGH MUCH OF
THE PERIOD. TOWARD THE END OF THE PERIOD...THE GFS IS TRYING TO
BRING A SHORT WAVE TROUGH AND UPPER LEVEL LOW THROUGH THE TOP OF
THE UPPER LEVEL RIDGE AND ACROSS SOUTHERN CANADA AND THE UPPER
MIDWEST. THE 24.00Z ECMWF MAINTAINS THE UPPER LEVEL RIDGE OVER THE
AREA WITH ANY TROUGHING OVER SOUTHWEST CANADA INTO THE NORTHERN
ROCKIES. WILL TREND TOWARD THE ECMWF SOLUTION AND KEEP THE ENTIRE
PERIOD DRY.

&&

.AVIATION...THROUGH 06Z SATURDAY
1140 PM CDT THU AUG 23 2012

MAIN FOCUS IS ON PRECIPITATION CHANCES EARLY IN THE FORECAST.
CLUSTER OF SHOWERS AND A FEW EMBEDDED THUNDERSTORMS PERSISTS
ACROSS CENTRAL MINNESOTA...WITH OTHERS DEVELOPING OVER WEST
CENTRAL WISCONSIN AND INTO SOUTHEAST MINNESOTA. MAJORITY OF THESE
REMAIN NORTH OF THE TAF SITES. CANNOT RULE OUT A FEW SHOWERS
AFFECTING EITHER TAF SITES PRIOR TO 12Z...IN RESPONSE TO A
LOW PRESSURE TROUGH MOVING EAST FROM CENTRAL MINNESOTA INTO
WISCONSIN. HOWEVER...THE BEST FORCING LOOKS TO REMAIN NORTH OF
THE TAF SITES...THUS ONLY VCSH REMAINS MENTIONED IN THE TAFS. VFR
CONDITIONS ARE EXPECTED ANYWAY DUE TO DRY LOW LEVEL AIR. IN
FACT...THE DRY LOW LEVEL AIR WILL REMAIN IN PLACE THROUGH FRIDAY
NIGHT...HELPING TO MAINTAIN VFR CONDITIONS. PLAN ON WINDS TO PICK
UP SOME DURING THE AFTERNOON HOURS...PARTICULARLY AT KRST BEING
MORE EXPOSED. GUSTS THERE COULD APPROACH 20 KT. EXPECT WINDS TO
DIMINISH DURING THE EVENING WITH COOLING.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
239 AM CDT FRI AUG 24 2012

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

&&

$$

SHORT TERM...04
LONG TERM...04
AVIATION...AJ







AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 1140 PM CDT THU AUG 23 2012

.SHORT TERM...TONIGHT
723 PM CDT THU AUG 23 2012

MAIN FORECAST CONCERN IS IF CONVECTION WILL MOVE INTO AND/OR
DEVELOP OVER THE FORECAST AREA TONIGHT.

00Z WATER VAPOR LOOP SHOWED A SHORTWAVE TROUGH ACROSS WESTERN
MINNESOTA. WEAK DPVA FORCING AHEAD OF THIS SHORTWAVE COMBINED WITH
WARM ADVECTION...AND MORE IMPORTANTLY INSTABILITY...HAS LED TO
SCATTERED SHOWER AND THUNDERSTORM DEVELOPMENT FROM SOUTHWEST INTO
CENTRAL MINNESOTA. MUCH OF THIS ACTIVITY WAS ALSO ON A WARM FRONT.
23Z RAP ANALYSIS DEPICTED MLCAPE VALUES AROUND 1500 J/KG WITH
MLCIN LESS THAN 50 J/KG WHERE THESE STORMS HAVE OCCURRED.

MODELS ARE IN GOOD AGREEMENT LIFTING THE SHORTWAVE TROUGH OVER
WESTERN MINNESOTA TO THE NORTHEAST TONIGHT...STRETCHING FROM
WESTERN LAKE SUPERIOR INTO NORTHERN WISCONSIN BY 12Z FRIDAY. BIG
QUESTION MARK IS HOW MUCH PRECIPITATION OCCURS WITH THIS TROUGH.
CONVECTION THUS FAR AT LEAST OVER SOUTHWEST MINNESOTA REALLY
SEEMS TIED TO DIURNAL INSTABILITY. OVER THE NEXT FEW HOURS...THE
MLCIN INCREASES GREATLY...OVER 100 J/KG BY 02Z PER THE RAP MODEL.
THEREFORE...THINK THOSE IN SOUTHWEST MINNESOTA WILL DISSIPATE
BEFORE THEY HAVE MUCH OF A CHANCE TO HEAD EAST OR NORTHEAST WITH
THE SHORTWAVE TROUGH. THOSE STORMS MORE OVER CENTRAL MINNESOTA ARE
MORE ON THE NOSE OF 850MB MOISTURE TRANSPORT...WHICH SHIFTS
NORTHEAST WITH THE SHORTWAVE TROUGH. SO ALTHOUGH MODELS SUCH AS
THE 23.18Z NAM/GFS AND 23.12Z ECMWF BRING CONVECTION INTO
NORTHWEST PORTIONS OF THE AREA...DEFINITELY HAVE DOUBTS. IN
FACT...THE 23.12Z HIRESW-ARW MODEL SUGGESTS THAT MUCH OF THE
CURRENT CONVECTION DISSIPATES BY 06Z...LEAVING THE OVERNIGHT DRY.
23.21Z HRRR ALSO HAS TRENDED DRIER...WITH THE EXCEPTION OF SOME
SCATTERED ELEVATED CONVECTION IT DEVELOPS ALONG/NORTH OF I-94
AFTER 10Z. FOR NOW...HAVE DELAYED ARRIVAL OF ANY PRECIPITATION
CHANCES TO AT LEAST 03Z...AND AFTER 03Z MOSTLY LOWERED
PRECIPITATION CHANCES EXCEPT FOR THE TAYLOR/CLARK AREA. THE REASON
FOR NOT ADJUSTING CHANCES IN TAYLOR/CLARK IS INDICATIONS OF
INCREASING 310K ISENTROPIC LIFT...REFLECTED IN BOTH THE 23.18Z NAM
AND 23.21Z HRRR.

IN SUMMARY...CONCERNED THAT NOT MUCH MAY HAPPEN FOR THE FORECAST
AREA TONIGHT. WILL WATCH CONVECTIVE TRENDS OVER THE NEXT FEW HOURS
AND ADJUST PRECIPITATION CHANCES AS NECESSARY.

.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
240 PM  CDT THU AUG 23 2012

23.12Z GFS/EC SHOW SUNDAY NIGHT THROUGH TUESDAY NIGHT LOOKING DRY AND
WARM AS A MID-LEVEL RIDGE OF HIGH PRESSURE BUILDS INTO THE CENTRAL
CONUS. LOOK FOR HIGHS MONDAY AND TUESDAY IN THE UPPER 70S TO MIDDLE
80S. BY WEDNESDAY INTO THURSDAY...WILL BE WATCHING LOW PRESSURE PUSH
ACROSS THE NORTHERN PLAINS TOWARD THE AREA. THIS SETS UP WAA
SCENARIO ACROSS THE AREA WITH A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS WEDNESDAY/WEDNESDAY NIGHT. OTHERWISE...LOOKS LIKE
ABOVE NORMAL TEMPERATURES WILL CONTINUE THROUGH THURSDAY WITH HIGHS
TOPPING OFF IN THE 80S.

&&

.AVIATION...THROUGH 06Z SATURDAY
1140 PM CDT THU AUG 23 2012

MAIN FOCUS IS ON PRECIPITATION CHANCES EARLY IN THE FORECAST.
CLUSTER OF SHOWERS AND A FEW EMBEDDED THUNDERSTORMS PERSISTS
ACROSS CENTRAL MINNESOTA...WITH OTHERS DEVELOPING OVER WEST
CENTRAL WISCONSIN AND INTO SOUTHEAST MINNESOTA. MAJORITY OF THESE
REMAIN NORTH OF THE TAF SITES. CANNOT RULE OUT A FEW SHOWERS
AFFECTING EITHER TAF SITES PRIOR TO 12Z...IN RESPONSE TO A
LOW PRESSURE TROUGH MOVING EAST FROM CENTRAL MINNESOTA INTO
WISCONSIN. HOWEVER...THE BEST FORCING LOOKS TO REMAIN NORTH OF
THE TAF SITES...THUS ONLY VCSH REMAINS MENTIONED IN THE TAFS. VFR
CONDITIONS ARE EXPECTED ANYWAY DUE TO DRY LOW LEVEL AIR. IN
FACT...THE DRY LOW LEVEL AIR WILL REMAIN IN PLACE THROUGH FRIDAY
NIGHT...HELPING TO MAINTAIN VFR CONDITIONS. PLAN ON WINDS TO PICK
UP SOME DURING THE AFTERNOON HOURS...PARTICULARLY AT KRST BEING
MORE EXPOSED. GUSTS THERE COULD APPROACH 20 KT. EXPECT WINDS TO
DIMINISH DURING THE EVENING WITH COOLING.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
240 PM CDT THU AUG 23 2012

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

&&

$$

SHORT TERM...AJ
LONG TERM....DAS
AVIATION...AJ








AREA FORECAST DISCUSSION

NWS NORTHERN INDIANA

 439 AM EDT SUN AUG 26 2012

.SHORT TERM...TODAY THROUGH MONDAY NIGHT.

TROUGHINESS FROM CLOSED UPPER LOW MOVING TOWARDS HUDSON BAY THIS
MORNING WILL ATTEMPT TO GRAB HOLD OF WEAK BUT MOISTURE LADEN WAVE
CURRENTLY IN SE KANSAS AND PULL IT NE TODAY INTO TONIGHT. LIGHTER
SHOWER ACTIVITY NOTED ACROSS PORTIONS OF WISCONSIN WITH MORE
WIDESPREAD/HEAVIER SHOWERS/STORMS FROM S CNTRL IOWA INTO SW MISSOURI
AND SE KANSAS. NEAR/SHORT TERM MODELS HAVE VARIETY OF SOLUTIONS IN
HANDLING OF THIS ENERGY AND EFFECTS ON THE AREA. PAST SEVERAL RUNS
OF HRRR HAVE SHOWN DEVELOPMENT SHOULD BE UNDERWAY ACROSS WESTERN
ILLINOIS IN AREA LL CONVERGENCE...30 KT LLJ AND PWATS AROUND 2
INCHES. HOWEVER...LITTLE PRECIP NOTED AND NO INDICATIONS OF ANYTHING
IMMINENT. AT THIS POINT...DISCOUNTING (BUT NOT DISCARDING) THIS IDEA
WHICH WOULD BRING IN SHOWERS TO WESTERN AREAS LATER THIS MORNING.
REMAINING MODELS LEAN TOWARDS AWAITING ARRIVAL OF WAVE INTO ILLINOIS
LATER TODAY INTO TONIGHT ALONG A COLD FRONT SET TO MOVE THROUGH
TONIGHT INTO MONDAY. GIVEN BEST DYNAMICS MOVING NORTH OF THE
AREA...WAVE WILL SLOWLY SHEAR OUT AS IT MOVES NORTHEAST.
HOWEVER...GIVEN DEEP MSTR IN PLACE (OVER 2 INCHES FROM OKLAHOMA INTO
SW MISSOURI)...EXPECT CURRENT ACTIVITY TO REMAIN INTACT/EXPAND AS IT
MOVES NORTHEAST. MAJORITY OF MODELS EVENTUALLY FOCUS LLJ INTO
NORTHERN ILLINOIS IN AXIS OF HIGHER PWATS...CAUSING ADDITIONAL
CONVECTION TO BREAK OUT. FROM THIS POINT IS WHERE MODELS DIVERGE
WITH ANYTHING FROM GLANCING BLOW OF SHOWERS IN NW AREAS...TO
WIDESPREAD SHOWERS/EMBEDDED STORMS...TO CONVECTION REMAINING MAINLY
SOUTH OF THE AREA (SOME HINTS OF THIS IN WATER VAPOR WITH GREATEST
MSTR SHIFTING MORE EAST THAN NORTH). DO THINK THAT MOST...IF NOT ALL
AREAS WILL SEE AT LEAST SOME MEASURABLE RAINFALL WITH BASIN AVERAGES
IN THE QUARTER TO HALF INCH RANGE. WITH POTENTIAL FOR MORE CELLULAR
SETUP VS WIDESPREAD AREA OF RAIN/STORMS HAVE OPTED TO CONTINUE WITH
ARRIVAL OF HIGH END CHC POPS NW AREAS LATER THIS
AFTERNOON...EXPANDING TO HIGHER END LIKELY ACROSS MUCH OF THE AREA
BY LATER TONIGHT.

HAVE NUDGED UP POPS SOMEWHAT MONDAY MORNING IN EASTERN AREAS WITH
CONCERNS ABOUT SLOWER DEPARTURE OF ENERGY. IF 3Z SREF WERE TO
VERIFY...SHOWERS/STORMS WOULD REMAIN ACROSS MUCH OF THE AREA THROUGH
MOST OF MONDAY. THIS MODEL IS PRESENTLY AN OUTLIER SO WHILE AT LEAST
CONSIDERED...DISCOUNTED FOR THE TIME BEING WITH DRYING CONDITIONS
FROM NW TO SE THROUGH THE DAY.

TEMPERATURES HAVE SERIOUS BUST POTENTIAL TODAY ACROSS THE AREA. IR
SAT DATA SHOWS CLOUD COVER TO BEGIN TO ARRIVE IN NW AREAS THIS
MORNING AND THEN INCREASING IN COVERAGE/THICKNESS INTO THIS
AFTERNOON. COOLEST HIGHS ARE EXPECTED IN THESE LOCATIONS AS A RESULT
OF THE LIMITED HEATING WITH WARMER TEMPS...CLOSE TO 90 EXPECTED
ACROSS PORTIONS OF NE INDIANA INTO NW OHIO. IF PRECIP DOES INDEED
WAIT UNTIL CLOSER TO THIS EVENING AND HIGH CLOUDS REMAIN THIN
ENOUGH...HIGHS IN THE NW WILL BE TOO COOL AND NEED ADJUSTING. FOR
NOW WILL GENERALLY LEAVE UNTOUCHED. MUGGY NIGHT IN STORE WITH DEWPTS
IN THE UPPER 60S TO AROUND 70 AND LOWS NEAR OR INTO THE 70S MUCH OF
THE NIGHT. ON MONDAY...TEMPS WILL REMAIN AN ISSUE WITH CLEARING
EXPECTED NW WHERE A NICE REBOUND COULD OCCUR GIVEN OVERNIGHT LOWS
ONLY AROUND 70...WITH SE AREAS SLOWER TO CLIMB WITH LINGERING CLOUD
COVER. HAVE KEPT MON/MON NGT LOWS AS IS.

&&

.LONG TERM...
TUESDAY THROUGH SATURDAY. FEW CHNGS WRT LONG TERM. CRNT CNTL PLAINS
SHORTWAVE TO MINOR NEWD AS ASSERTIVE MANITOBA MID TROPOSPHERIC
VORTEX SWEEPS INTO JAMES BAY BY ERLY MONDAY. SFC RIDGE IN WAKE TO
BUILD INTO GRTLKS RGN MIDWEEK TO ASSERT DRY/SUBSIDENT AIRMASS
PERSISTING THROUGH LATTER HALF OF WEEK. SHALLOW CAA/925MB THERMAL
TROF AMID FLOW VEERING TO NERLY PEAKS WED AM...THOUGH REBOUND TO
NEAR NORMAL MAX TEMPS ANTICIPATED AMID STRONG INSOLATION AFFORDED BY
DRY AIRMASS/PWAT NEAR 0.50 INCHES. THEREAFTER AIRMASS MODIFIES GRDLY
WARMER NEATH 4 CORNERS RIDGE EXTRUSION NEWD INTO SWRN GRTLKS BY
DY5...THEREAFTER CULMINATING INTO REX BLOCK OF POST TROPICAL
REMNANTS OF ISAAC DY6. WHILE ECMWF HAS UNDERGONE SOME CONSIDERABLE
DEGREE OF VACILLATION IN PRIOR ITERATIONS...FAVOR 26/00 ECMWF WITH
NOTABLE ADHERENCE TO NAM/4KM WRF/OFFICIAL TRACK OF ISAAC IN SHORT
TERM...IN STARK OPPOSITION TO CONFUNDITY OF GFS FAR WRN TRACK INTO
ERN OK. HAVE TEMPERED POPS DY7 SOMEWHAT TOWARD MULTI MODEL BLEND
WITH SLIGHT NUDGE TOWARD LATEST ECMWF IN DEFERENCE TO CONSISTENCY...
PENDING FURTHER ASSESSMENT.


&&

.AVIATION...06Z TAFS

NO SIG CHANGES TO TAFS WITH LOW TO MEDIUM CONFIDENCE IN EVOLUTION
OF RAIN CHANCES/FLGT IMPACTS AT BOTH SITES LATER THIS AFTERNOON
INTO TONIGHT.

TO START OFF...NO CHANGES MADE PRIOR TO 18Z WITH SOME POTENTIAL
FOR SHALLOW FOG/MIST AT BOTH SITES. TEMP/DEWPT SPREAD ALREADY
DECREASING AT KFWA WITH LARGER DEPRESSION AT KSBN WHICH MAY ALLOW
FOR FOG DEVELOPMENT TO HOLD OFF. AFTER THIS FOCUS WILL TURN TO
PRECIP CHANCES LATE THIS AFTERNOON INTO TONIGHT. CONVECTION
EXPECTED TO DEVELOP ACROSS ILLINOIS AND MAY MOVE INTO INDIANA LATE
AFTERNOON AND ESPECIALLY TONIGHT. TIMING/COVERAGE OF SHOWER/TSTORM
ACTIVITY REMAINS QUESTIONABLE WITH SEVERAL MODELS KEEPING BULK OF
PRECIP CLOSER TO KSBN AND POTENTIALLY NOT UNTIL THE 3 TO 6Z
WINDOW. AT THIS POINT...KFWA WAS LEFT DRY THROUGH 06Z WITH MVFR
VSBY INTRODUCED AT KSBN TOWARDS THE END OF THE FORECAST PERIOD
WHEN MODELS SEEM TO AGREE AT THE BEST POTENTIAL...LIKELY LINGERING
THROUGH 12Z.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SHORT TERM...FISHER
LONG TERM...MURPHY
AVIATION...FISHER






AREA FORECAST DISCUSSION

NWS QUAD CITIES IA IL

 338 AM CDT SUN AUG 26 2012

.SYNOPSIS...
WEAK UPPER LEVEL WESTERLY FLOW CONTINUES OVER NEARLY ALL OF THE
CONUS. CORRESPONDINGLY WEAK 500MB TROUGH SPANS THE PLAINS FROM
SOUTHERN MINNESOTA INTO WEST TEXAS. PLUME OF LOW LEVEL MOISTURE IS
FEEDING FROM THE GULF OF MEXICO INTO THE UPPER MIDWEST...WITH 850MB
DEW POINTS AT OR ABOVE 15C OVER A SIGNIFICANT PORTION OF THE
SOUTHERN PLAINS AND LOWER MS VALLEY. AT THE SURFACE...LOW PRESSURE
IS CENTERED OVER KANSAS CITY THIS MORNING WITH A TROUGH EXTENDING TO
ITS SOUTHWEST...AND THE BEGINNINGS OF A WEAK WARM FRONT DEVELOPING
ACROSS NORTHERN MISSOURI AND SOUTHERN ILLINOIS.

&&

.SHORT TERM...TODAY AND TONIGHT...
FIRST WAVE OF SHOWERS ONGOING THIS MORNING OVER NORTHERN PORTIONS OF
THE CWFA...IN A BROAD AREA OF MID LEVEL ISENTROPIC LIFT AROUND
305K.  MAIN SHOW DRIVEN BY THE UPPER TROUGH IS NOW KNOCKING ON OUR
DOOR OVER SOUTHCENTRAL IOWA.  PRECIPITABLE WATERS ABOVE 2
INCHES...ABOUT 175 PERCENT OF NORMAL...OVER THE ENTIRE CWFA THIS
MORNING SUGGEST HIGHLY EFFICIENT RAINFALL PROCESSES. GIVEN THE WEAK
UPPER FLOW...SYSTEM WILL BE SLOW TO PROGRESS...FURTHER PADDING THE
RAINFALL TOTALS.  ALTHOUGH ONSET IS A BIT SLOWER THAN PREVIOUSLY
FORECAST...STILL LOOKS LIKE WE SHOULD SEE WIDESPREAD AMOUNTS NEAR
ONE INCH.  MID LEVEL LAPSE RATES SUGGEST POTENTIAL FOR WIDESPREAD
THUNDER IS LOW.  HOWEVER...ISOLATED EMBEDDED THUNDER HAS CONTINUED
OVERNIGHT OVER NORTHERN MISSOURI AND WILL MAINTAIN MENTION OF
ISOLATED THUNDER AS THE UPPER FORCING MOVES INTO THE AREA THIS
MORNING.

FAVORED THE RAP AND NAM TODAY AS BOTH HAVE A DECENT HANDLE ON THE
SURFACE FEATURES.  BASED ON THE NAM SOLUTION...BROAD SCALE LIFT
CONTINUES THROUGH MOST OF THE DAY AHEAD OF THE SURFACE LOW.  SHOULD
SEE PRECIP ENDING FROM WEST TO EAST LATE TODAY AND INTO TONIGHT AS
THE SYSTEM CLEARS THE AREA.

DMD

.LONG TERM...MONDAY THROUGH NEXT SATURDAY...
MAINLY DRY WITH NEAR TO ABOVE NORMAL TEMPS AS SFC AND UPPER RIDGING
DOMINATES FOR MUCH OF THE PERIOD.

MON-WED... DRY AND FEW DEGS COOLER WITH LIGHT NORTHERLY WINDS TO
PERSIST FOR MUCH OF THE PERIOD VEERING TO EASTERLY BY WED AS SFC
HIGH SHIFTS THROUGH GREAT LAKES. H85 THERMAL GRADIENT W-E SHOWN
TO RESIDE OVER CWA WITH H85 TEMPS MAINLY IN RANGE OF 14-18C. THESE
VALUES MIXED TO SFC CLOSER TO DRY ADIABATICALLY SUPPORT WIDESPREAD
80S WITH COOLEST READINGS E/NE AND WARMEST S/SW. LOWS NEAR TO
BELOW COOLEST GUIDANCE WITH GOOD RADIATIONAL COOLING SETUP DURING
THE NIGHTS... WITH 50S FOR LOWS FAIRLY COMMON BOTH TUE AND WED AM.
DRY AIR SHOULD PROMOTE LARGE DIURNAL RANGES ON ORDER OF 30-35+ DEGS.

THU-SAT... UPPER LEVEL RIDGE BUILDS INTO REGION BY LATE WEEK AND THEN
FLATTENS. TEMPS ALOFT WARM WITH H85 TEMPS IN THE RANGE OF 20-25C.
BUT MODELS INDICATE WEAK MIXING REGIME WITH SFC RIDGE AXIS IN CLOSE
PROXIMITY... THUS NOT ABLE TO TAP FULL WARMTH AND SPARING US FROM
BAKING. THEREFORE... CONTINUATION OF MAINLY 80S FOR HIGHS. PCPN CHCS
LATE IN EXTENDED DEPENDENT ON MOVEMENT OF ISAAC REMNANTS.
OVERALL... HAVE SERIOUS DOUBTS THAT WE WILL SEE ANY IMPACT FROM
ISAAC DESPITE LATEST GFS AND GEM SOLUTIONS BRINGING REMNANTS
EITHER UP OVER CWA OR JUST GLANCING S/E CWA. TYPICALLY NEED LANDFALL
TO OCCUR IN TX OR WRN LA FOR THESE SYSTEMS TO HAVE ANY IMPACT
FOR OUR CWA. AT 06Z... GFS AND GEM WERE AROUND 3 MB TOO WEAK WITH
ISAAC AND THIS COULD AT LEAST PARTIALLY EXPLAIN THEIR MORE WESTERN
TRACK. IF WE SEE CONTINUED STRENGTHENING TDY TO HURRICANE THEN WOULD
EXPECT ISAAC TO START CURVING... AND IT WOULD SEEM VERY LIKELY THAT
ISAAC WOULD CONNECT WITH EASTERN TROUGH AND GET PULLED NORTHWARD.
THE KEY WILL BE AMOUNT/RATE OF INTENSIFICATION AS THE SLOWER ISAAC
TAKES TO RAMP UP THE MORE AND MORE A WESTERN TRACK WOULD BE POSSIBLE.
HAVE FOLLOWED HPC GUIDANCE CLOSELY LATE IN THE EXTENDED AND WILL HAVE
MAINLY DRY FCST FRI-SAT WITH ISAAC REMNANTS STAYING TO OUR E/SE.

MCCLURE

&&

.AVIATION...
A WEAK LOW PRESSURE SYSTEM WILL BRING WIDESPREAD RAINFALL TO THE
LOCAL AREA TODAY. CIGS AND VSBYS ARE EXPECTED TO DROP BELOW IFR
THRESHOLDS BY 18Z AT AREA TAF SITES. CONDITIONS WILL IMPROVE AGAIN
FROM WEST TO EAST AFTER 00Z.      DMD

&&

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

&&

$$

DMD/MCCLURE






AREA FORECAST DISCUSSION

NWS DODGE CITY KS

 337 AM CDT SUN AUG 26 2012

...UPDATED SYNOPSIS AND SHORT TERM SECTIONS...

.SYNOPSIS...
ISSUED AT 336 AM CDT SUN AUG 26 2012

ON THE SYNOPTIC SCALE...THE MID LEVEL TROUGH THAT BROUGHT ALL THE
RECENT RAINS EXTENDED FROM CENTRAL IOWA TO EASTERN KANSAS TO
NORTHWEST TEXAS EARLY THIS MORNING. SEVERAL THUNDERSTORM CLUSTERS
THRIVED THROUGH THE NIGHT ALONG THE TROUGH AXIS...PARTICULARLY FROM
NORTHERN OKLAHOMA INTO SOUTHEASTERN KANSAS. WATER VAPOR LOOP AS OF
08Z SHOWED SIGNIFICANT MID LEVEL DRYING IN THE WAKE OF THIS TROUGH
AXIS WITH SHORT WAVE RIDGING BUILDING IN ITS WAKE. ALSO IN ITS WAKE
IS A RATHER NON-EXISTENT MEAN SEA LEVEL PRESSURE FIELD WITH THE MSLP
ANALYSIS RATHER ISOBARIC IN NATURE AS MSLP WAS 1013 OR 1014MB FROM
WESTERN KANSAS INTO NEBRASKA, WESTERN IOWA, AND THE DAKOTAS. THIS
RESULTED IN WIDESPREAD CALM OR NEARLY CALM WINDS WITH RESIDUAL
MOISTURE REMNANT FROM BOTH THE RECENT RAINS AND INFLUX OF GULF OF
MEXICO MOISTURE INTO THE AREA AHEAD OF THE TROUGH WHICH WAS NOT
PUSHED OUT OF HERE WITH NO COLD FRONT.  A BAROCLINIC WAVE WHICH DID
PASS ACROSS THE SOUTHERN CANADIAN PRAIRIES DID PUSH A COLD FRONT
SOUTH YESTERDAY BUT STALLED OUT, WEAKENED, AND ULTIMATELY DIED OVER
THE SANDHILLS OF NEBRASKA.  AS OF 0815Z...THE 11-3.9 MICRON
SATELLITE LOOP CONFIRMED THE DEVELOPMENT OF LOW STRATUS AND FOG
ACROSS NORTH-CENTRAL KANSAS WHICH WAS PUSHING TOWARD THE HAYS AREA.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 336 AM CDT SUN AUG 26 2012

IN THE VERY SHORT TERM...LOW STRATUS AND FOG WILL BE THE MAIN ISSUE
ON THE AVIATION SIDE OF THINGS.  THE GRIDS ALREADY REFLECT
DEVELOPMENT OF CLOUDS AND PATCHY FOG...BUT WILL TRIM BACK THE
WESTERN EDGE OF THIS (ROUGHLY DIGHTON TO DODGE CITY TO COLDWATER
LINE) PER GUIDANCE FROM THE LATEST RUNS OF THE HRRR MODEL AS WELL AS
TRENDS ON SATELLITE.  THE FOG AND STRATUS PROBABLY WONT EVEN MAKE IT
THAT FAR WEST.  THE REST OF THE FORECAST FOR TODAY AND TONIGHT IS
FAIRLY STRAIGHT FORWARD UNDER THE MID LEVEL RIDGE AXIS.  HIGHS TODAY
WILL BE UPPER 80S TO NEAR 90 AS DIRECT INSOLATION WILL PREVAIL.
SURFACE WINDS WILL BEGIN TO RESPOND TO LOWERING PRESSURE OUT WEST
OVER THE HIGHER TERRAIN...BUT MAINLY ACROSS THE WESTERN COUNTIES
CLOSE TO THE COLORADO BORDER (WEST OF HIGHWAY 83). TONIGHT...ANOTHER
CLEAR AND (NEAR) CALM NIGHT IS EXPECTED WITH LOWS IN THE LOWER TO
MID 60S.  A PATCHY AREA OF LIGHT FOG WILL PROBABLY DEVELOP AGAIN IN
LOW LYING AREAS GIVEN IDEAL RADIATIONAL COOLING AND MOIST
GROUND...BUT THE COVERAGE OF ANY FOG DOES NOT REALLY WARRANT
INCLUSION IN GRIDS AT THIS TIME.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 123 AM CDT SUN AUG 26 2012

A RELATIVELY DRY PERIOD IS EXPECTED ACROSS WESTERN KANSAS AS MEDIUM
RANGE MODELS CONTINUE TO INDICATE A LARGE UPPER LEVEL RIDGE OF HIGH
PRESSURE PREVAILING ACROSS THE COLORADO ROCKIES AND THE WESTERN HIGH
PLAINS THROUGH AT LEAST MID WEEK. A GRADUAL WARMING TREND IS LIKELY
THROUGH AT LEAST WEDNESDAY AS A LEE SIDE TROUGH OF LOW PRESSURE
HELPS INFLUENCE A LOW LEVEL SOUTHERLY FLOW ACROSS WESTERN KANSAS
THROUGH MUCH OF THE PERIOD. FOR MONDAY, THE NAM, GFS, AND ECMWF SHOW
H85 TEMPERATURES RANGING FROM JUST ABOVE 20C ACROSS CENTRAL KANSAS
TO JUST ABOVE 25C NEAR THE COLORADO BORDER. ALONG WITH PLENTY OF
SUNSHINE, LOOK FOR HIGHS NEAR TO JUST ABOVE 90F MONDAY AFTERNOON.
THE WARMING TREND WILL CONTINUE WITH HIGHS EXPECTED UP INTO THE LOW
TO MID 90S(F) THROUGH AT LEAST THURSDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 106 AM CDT SUN AUG 26 2012

THE MAIN DIFFICULTY IN THE AVIATION FORECAST IS HOW MUCH, IF AT ALL,
GROUND CONDITIONS WILL DETERIORATE IN RADIATION FOG FORMATION. VERY
LIGHT, IF NOT CALM WINDS WILL REMAIN THROUGH THE NIGHT, AND BY
DAYBREAK VISIBILITY SHOULD FALL IN LIGHT FOG FORMATION AT DDC AND
HYS. WILL GO WITH A TEMPO GROUP FOR THE 11-13Z TIME FRAME BRINGING
VISIBILITY DOWN TO 1 MILE. I DO NOT HAVE THE CONFIDENCE TO GO ANY
LOWER THAN A MILE...BUT SOME PATCHY DENSE FOG MAY DEVELOP NEAR OR
OVER EITHER DDC AND HYS FOR A BRIEF TIME RIGHT AT DAYBREAK.
OTHERWISE...VFR CONDITIONS WILL RESUME SHORTLY AFTER SUNRISE WITH A
8-10 KNOT WIND FROM THE NORTHEAST EXPECTED THE REMAINDER OF THE DAY.


&&

.PRELIMINARY POINT TEMPS/POPS...
DDC  88  64  91  62 /   0  10   0   0
GCK  90  61  92  61 /   0  10   0   0
EHA  90  63  92  61 /   0  10   0   0
LBL  88  64  92  62 /   0  10   0   0
HYS  88  63  91  61 /   0  10   0   0
P28  87  67  92  64 /   0  10   0   0

&&

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

$$

SYNOPSIS...UMSCHEID
SHORT TERM...UMSCHEID
LONG TERM...JJOHNSON
AVIATION...UMSCHEID







AREA FORECAST DISCUSSION

NWS GOODLAND KS

 1014 PM MDT SAT AUG 25 2012

.UPDATE...
ISSUED AT 956 PM MDT SAT AUG 25 2012

OVERALL FORECAST LOOKED TO BE IN GOOD SHAPE...BUT DECIDED TO
EXTEND THE COVERAGE OF THE FOG FURTHER WEST TO THE COLORADO BORDER BASED
ON THE TRENDS IN MOS GUIDANCE. AM THINKING THE WESTERN EXTENT OF
THE FOG WILL BE MOSTLY CONFINED TO LOW-LYING AREAS DUE TO THE
LOWER RH VALUES IN THE BOUNDARY LAYER. FOR THE HILL CITY TO EAST
OF MCCOOK ADDED A MENTION OF WIDE SPREAD FOG SINCE ALMOST ALL
GUIDANCE PLACES FOG OVER OR JUST EAST OF THAT AREA. AGREE WITH
THE PREVIOUS SHIFT THE LOWER VISIBILITIES WILL BE OVER THE EASTERN
PART OF THE AREA...MAINLY ALONG AND EAST OF A RUSSELL SPRINGS TO
MCCOOK LINE. WITH MOST GUIDANCE CURRENTLY PLACING VISIBILITIES OF
TWO MILES FOR THESE LOCATIONS...WOULD NOT BE SURPRISED IF SOME
LOCATIONS HAVE VISIBILITIES DROP TO A HALF MILE...ESPECIALLY IN
LOW- LYING AREAS. THE FOG SHOULD BURN OFF BY MID MORNING.

DO NOT PLAN ON ISSUING A DENSE FOG ADVISORY SINCE POINT SOUNDINGS
STILL SHOW A VERY SHALLOW SATURATED LAYER AT THE SURFACE. WOULD
PREFER TO SEE A DEEPER SATURATED LAYER BEFORE CONTEMPLATING AN
ADVISORY. IN ADDITION THE 0Z MOS GUIDANCE CAME IN WITH SLIGHTLY
BETTER VISIBILITIES WHICH FURTHER DECREASES CONFIDENCE IN THE NEED
FOR AN ADVISORY. MID SHIFT WILL MONITOR THROUGH THE NIGHT TO SEE
IF VISIBILITIES DROP MORE THAN FORECAST.

&&

.SHORT TERM...(THIS EVENING)
ISSUED AT 108 PM MDT SAT AUG 25 2012

RADAR IS SHOWING A DECREASING TREND WITH THE LIGHT PRECIPITATION.
THIS IS A RESULT OF THE MID LEVEL LOW MOVING OFF TO THE EAST.
STRONG MID LEVEL SUBSIDENCE AND DRYING MOVING INTO THE NORTHWEST
PORTION ALREADY. SO HAVE TONIGHT DRY. LIGHT UPSLOPE TO LIGHT AND
VARIABLE WINDS WILL BE IN PLACE BY LATER TONIGHT. DRIER AIR FROM
THE SURFACE THROUGH MID LEVELS WILL MOVE INTO THE WESTERN PORTION
WITH INCREASING LOW LEVEL MOISTURE IN THE EASTERN PORTION. SO HAVE
INCREASED CLOUD COVER IN THE EAST AND HAVE EXPANDED THE AREA OF
FOG FURTHER WEST AND INCREASED COVERAGE TO AREAS IN THE FAR EAST.
COOLER MINS WILL BE IN THE WEST WITH THE DRIER AIR.

.LONG TERM...(SUNDAY THROUGH SATURDAY)
ISSUED AT 225 PM MDT SAT AUG 25 2012

SUNDAY-TUESDAY...NEAR TERM MODELS IN REASONABLE AGREEMENT THAT 594
DM RIDGE WILL BEGIN TO BUILD OVER THE AREA THROUGH THE
PERIOD...GENERALLY BRINGING AN END TO THE MORE WIDESPREAD
PRECIPITATION THREAT OF THE PAST FEW DAYS. INITIAL CONCERN WILL BE
HOW QUICKLY H5 TROUGH MOVES EAST OUT OF THE AREA AND WHETHER OR IT
WILL CONTINUE TO LINGER ACROSS THE EASTERN CWA. LATEST OPERATIONAL
GUIDANCE AS WELL AS SREF DATA SUPPORT TROUGH BEING WELL TO THE EAST
OF THE CWA BY SUNDAY MORNING WITH LARGE SCALE SUBSIDENCE BRINGING AN
END TO PRECIPITATION THREAT BY SUNRISE. STRONGEST SUBSIDENCE WILL
REMAIN OVER EASTERN CWA AS SHORT WAVE TROUGH DEPARTS THE AREA WITH
FAIRLY NEUTRAL LARGE SCALE FORCING ACROSS THE WEST DESPITE SLOWLY
AMPLIFYING TROUGH. WITH NO LARGE CHANGE IN AIR MASS
EXPECTED...ATMOSPHERE WILL DESTABILIZE AS EASTERLY FLOW BRINGS 50+
TDS INTO EASTERN COLORADO ALONG SFC TROUGH. SOUNDINGS AND MIXED
LAYER CINH FIELDS SUGGEST THERE WILL BE ROUGH 50 J/KG OF CINH ACROSS
THE AREA AND WHILE PERSISTENT CONVERGENCE MAY BE ENOUGH TO INITIATE A
STORM OR TWO...CONFIDENCE IN THIS SCENARIO IS LOW. GIVEN WEAK WINDS
ALOFT STORMS WOULD STRUGGLE TO MOVE OFF ON THE INITIATION AREA FOR
MOST OF THE AFTERNOON AND LATE EVENING. OTHERWISE WITH TEMPERATURES
GRADUALLY WARMING ALOFT AND MOISTURE PROFILES DIMINISHING THROUGH
TUESDAY THINK PRECIPITATIONS CHANCES WILL BE VERY LOW UNDER LARGE
SCALE RIDGE. TEMPERATURES WILL GRADUALLY WARM THROUGH THE
PERIOD...ALTHOUGH WITH SFC TROUGH TO THE NORTHWEST AND PERSISTENT
SFC RIDGE ACROSS EASTERN CWA HAVE A FEW CONCERNS THAT COOLER AIR MASS
MAY LINGER IN THE EASTERN CWA SO HAVE NOT RAISED TEMPS ALL THAT MUCH
IN THIS AREA.

IN THE EXTENDED (TUES NIGHT-SATURDAY)...MEDIUM RANGE MODELS IN
GENERAL AGREEMENT WITH LARGE SCALE PATTERN AROUND THE CWA...BUT
SIGNIFICANT DIFFERENCES WITH THE HANDLING OF ISAAC WHICH DOES
INFLUENCE THE OVERALL PATTERN...WHICH INCREASES THE UNCERTAINTY OF
THE OVERALL FORECAST. WHILE GFS/GEM AND GEFS MEAN ARE IN GOOD
AGREEMENT...SEEING THE 12Z ECWMF DATA MAKES ME THINK THAT THERE
REMAINS A GREAT DEAL OF UNCERTAINTY WITH RESPECT TO OVERALL PATTERN
FOR THE COMING WEEK AND THINK CURRENT CONSENSUS FORECAST FOR THE
MOST PART IS REASONABLE FOR THE PERIOD. IN GENERAL...EXPECT TEMPS TO
WARM BACK INTO THE LOWER TO MID 90S UNDER LARGE SCALE RIDGE. WEAK
FRONTAL ZONE MAY IMPACT NORTHWEST CWA BRINGING A SMALL CHANCE FOR
PRECIPITATION BUT LATEST DATA DOES NOT SUPPORT MORE THAN A 10-20%
CHANCE THROUGH A MAJORITY OF THE PERIOD.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 456 PM MDT SAT AUG 25 2012

VFR TO IFR CONDITIONS ARE FORECAST FOR THE 0Z TAFS. LATEST
MODEL/MOS GUIDANCE IS SPLIT ON WHETHER FOG/STRATUS WILL DEVELOP AT
KMCK AND HOW FAR WEST IT WILL EXTEND. LATEST HRRR/NAM/SREF KEEP
THE FOG EAST OF KMCK WHILE GFS/RUC/MOS PLACE THE FOG AS FAR WEST
AS KGLD. WITH A SUCH A DISAGREEMENT BETWEEN THE VARIOUS GUIDANCE
WILL NOT ALTER THE TAFS TOO MUCH FROM THE 18Z ISSUANCE. HOWEVER
POINT SOUNDINGS FROM THE RUC ARE NOT TOO SUPPORTIVE OF LOW
VISIBILITIES AT KMCK...WITH A DRY LAYER SANDWICHED BETWEEN
SATURATION AT THE SURFACE AND ROUGHLY 1500 FT AGL. WILL WAIT UNTIL
THE 6Z TAF ISSUANCE BEFORE MAKING TOO MANY CHANGES. OTHERWISE
CONDITIONS SHOULD QUICKLY IMPROVE AFTER 12Z WITH LIGHT WINDS
THROUGH SUNDAY.


&&

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

$$

UPDATE...JTL
SHORT TERM...BULLER
LONG TERM...JRM
AVIATION...JTL







AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 505 AM EDT SUN AUG 26 2012

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 503 AM EDT SUN AUG 26 2012

SYNOPSIS...WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL
LOW NE OF LAKE WINNIPEG RESULTING IN SW FLOW FROM THE UPPER MS VALLEY
INTO THE NRN GREAT LAKES. AT THE SFC... A COLD FRONT EXTENDED FROM A
TRIPLE POINT WEST OR JAMES BAY SW TO NEAR CYQT/KDLH. -SHRA INTO
CNTRL UPPER MI WERE SUPPORTED BY A WEAK SHRTWV OVER NRN WI IN THE
MOISTURE PLUME REACHING FROM THE SRN PLAINS INTO UPPER MI AND NRN
ONTARIO. ADDITIONAL SHRA WERE ALSO MOVING NE INTO CNTRL WI.
A LINE OF TSRA HAD DEVELOPED AHEAD N OF LAKE SUPERIOR AHEAD OF THE
COLD FRONT ASSOCIATED WITH STRONGER QVECTOR CONV AND HEIGHT FALLS
AHEAD OF THE MID LEVEL TROUGH.

TODAY AND TONIGHT...EXPECT SCT SHRA TO CONTINUE INTO THE CNTRL AND EAST CWA
THIS MORNING...PER RADAR/SATELLITE TRENDS AS ANOTHER WEAK SHORTWAVE
LIFTS TOWARD THE AREA. EVEN THOUGH THICKER CLOUD COVER WILL HOLD TEMPS
DOWN COMPARED TO SATURDAY...EVEN MODEST WARMING AHEAD OF THE FRONT
SHOULD STILL PUSH MAX READINGS TO AROUND 80. WITH THE TEMP
RECOVERY...MUCAPE VALUES MAY ALSO CLIMB INTO THE 500-1000 J/KG RANGE
TO SUPPORT TSRA CHANCES BY LATE THIS MORNING INTO THIS EVENING AS THE
COLD FRONT EDGES THROUGH THE AREA. HOWEVER...SINCE LOW LEVEL CONV AND
FORCING WITH THE FRONT WILL BE RELATIVELY WEAK...THE FCST ONLY
INCLUDES LOWER END CHANCE POPS. ANY REMAINING SHRA/TSRA WILL EXIT THE
ERN CWA AFT 03Z.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 503 AM EDT SUN AUG 26 2012

OVERALL PATTERN FOR THE LONG TERM WILL FEATURE AN UPPER TROUGH
PUSHING INTO THE UPPER GREAT LKS ON SUN NIGHT AND MON BEFORE
SHIFTING E INTO THE NEW ENGLAND STATES. THIS WILL ALLOW AN UPPER
RIDGE TO BUILD OVER THE ROCKIES AND NORTHERN PLAINS WHILE SLOWLY
SHIFTING E INTO THE UPPER MISS VALLEY FOR WED AND THE UPPER GREAT
LKS ON THURS. AT THE SFC...NW FLOW WILL TAKE HOLD FOR MON AHEAD OF
HIGH PRESSURE SLIDING OUT OF THE CANADIAN PRAIRIES AND NORTHERN
PLAINS AND INTO THE UPPER MISS VALLEY. THIS HIGH WILL SLIDE SE OVER
THE UPPER GREAT LAKES REGION FOR MON NIGHT THROUGH WED AND THEN
SLIDE SOUTHEAST INTO THE LOWER GREAT LAKES ON WED NIGHT AND THURS.

MODELS CONSISTENT ON SHORTWAVE MOVING THROUGH ON MON AFTN UNDER THE
NW FLOW ALOFT. H700-500 MOISTURE IS VERY LIMITED...WITH THE BEST
AREA OVER LK SUPERIOR AND ALIGNED WITH STEEPENING LAPSE RATES TO 6.5
C/KM. LOWER MOISTURE IS ALSO LIMITED AND MODELS TRY TO DIMINISH IT
AS IT DROPS SE ACROSS THE CWA. WITH THE MOISTURE AROUND
H850...THINKING IT SHOULD BE ENOUGH FOR AT LEAST SOME DIURNAL CU.
BUT WITH LITTLE TO NO INSTABILITY DUE TO CAPPING INVERSION BETWEEN
H800-600...DON/T EXPECT MUCH MORE THAN THAT. THEREFORE...HAVE BUMPED
THE CLOUDS UP A LITTLE OVER NRN/ERN LK SUPERIOR WHERE THE BETTER MID
LVL MOISTURE IS LOCATED AND ALSO OVER THE LAND AREAS WITH THE
DIURNAL CU.

WITH THE HIGH MOVING IN MON NIGHT...SHOULD BE A DRY PERIOD FOR MUCH
OF THE WORK WEEK. DIURNAL CU POSSIBLE AGAIN ON TUES...BUT THIS TIME
CONFINED TO THE INTERIOR CENTRL AND NEAR LK MI AS THE DRIER AIR FROM
THE HIGH SETTLES IN. UPPER TROUGH SLIDING THROUGH WITH THE CANADIAN
HIGH WILL LEAD TO COOLER TEMPERATURES FOR MON/TUES...WITH HIGHS
MAINLY IN THE 70S. THEN AS THE HIGH SHIFTS SE...SWRLY RETURN FLOW
WILL START TO PUSH TEMPS BACK UP AND ON A BREEZY THURS...HIGHS WILL
APPROACH 90 DEGREES ONCE AGAIN UNDER THE UPPER RIDGE.

THEN FOR FRI/SAT...EXTENDED MODELS AND THEIR ENS MEANS CONSISTENT ON
THE IDEA OF THE UPPER RIDGE FLATTENING OUT DUE TO A SHORTWAVE
PULLING OUT OF THE UPPER TROUGH OVER THE PAC NW. STILL SOME
DIFFERENCES IN THE INTENSITY OF THE WAVE AND THE EXACT TRACK...BUT
THE TIMING OF MOVING FROM OREGON TO NRN ONTARIO ON THURS/FRI IS
CONSISTENT. THIS WOULD LEAD TO A WEAK COLD FRONT MOVING ACROSS THE
AREA ON THURS NIGHT AND FRI. RIGHT NOW...APPEARS TO BE FAIRLY
DRY...SO WILL ONLY MENTION SLIGHT CHANCES OVER THE NW HALF OF LK
SUPERIOR. THINGS REALLY START TO DIFFER ON SAT...AS 00Z GFS WANTS TO
PULL ANOTHER UPPER WAVE ACROSS SRN ONTARIO. 00Z GFS ENS MEAN DOESN/T
FOLLOW THIS IDEA AND STAYS CLOSER TO 12Z ECMWF DETERMINISTIC AND ENS
MEAN ON WRLY FLOW. THUS...WILL FOLLOW THAT IDEA AND KEEP MUCH OF THE
AREA DRY AND CONTINUE THE ABOVE NORMAL TEMPS WITH HIGHS IN THE UPPER
70S AND LOWER 80S.
&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 149 AM EDT SUN AUG 26 2012

A SLOW MOVING LO PRES TROF WILL BRING THE THREAT OF SOME -SHRA AND
PERHAPS A TS W-E TO THE 3 SITES DURING AT LEAST PART OF THIS FCST
PERIOD. THE QUICKER PASSAGE OF THIS BNDRY THIS AFTN AND AN INFLUX OF
DRIER AIR IN ITS WAKE WL END THE PCPN THREAT AT IWD/CMX EARLIER THAN
AT SAW. TS CHCS ARE TOO LO TO BE SPECIFIC FOR TIMING ATTM...BUT THE
BEST SHOT FOR A TS WOULD BE LATE TODAY AT SAW. ALTHOUGH MVFR
CONDITIONS ARE PSBL IMMEDIATELY AHEAD OF THE COLD FROPA AT ALL 3
SITES AND UNDER ANY HEAVIER SHRA...LACK OF SGNFT LLVL MOISTENING
SUGS VFR CONDITIONS WL PREVAIL.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 503 AM EDT SUN AUG 26 2012

WINDS ARE EXPECTED TO REMAIN BELOW 30KTS THROUGH THE FORECAST PERIOD.
LOW PRES OVER CENTRAL MANITOBA LOW PRESSURE WILL LIFT ACROSS HUDSON
BAY TODAY...AND NORTHERN QUEBEC ON MONDAY. THIS WILL KEEP A TROUGH
ACROSS LAKE SUPERIOR THROUGH SUNDAY NIGHT. HIGH PRESSURE STRETCHING
FROM MANITOBA THE CENTRAL PLAINS MONDAY MORNING WILL SLOWLY BUILD
ACROSS THE UPPER GREAT LAKES THROUGH TUESDAY...BEFORE SINKING TO THE
LOWER GREAT LAKES WEDNESDAY. A LOW WILL SLIDE FROM CENTRAL MANITOBA
TO CENTRAL ONTARIO AND HUDSON BAY BY THURSDAY EVENING...ALLOWING A
TROUGH TO DIP OVER LAKE SUPERIOR.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...JLB
LONG TERM...SRF
AVIATION...KC
MARINE...JLB







AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

 1155 PM CDT SAT AUG 25 2012

.UPDATED FOR 06Z AVIATION DISCUSSION...

&&

.DISCUSSION...

A DUO OF WEAK SHORTWAVES IS DETECTABLE IN EARLY AFTERNOON RADAR
IMAGERY...ONE ROTATING FROM EAST CENTRAL MN INTO WEST CENTRAL
WISCONSIN...AND THE OTHER OVER NORTHEAST IA. MEANWHILE...THE
PRECIPITATION ASSOCIATED WITH THE NORTHERN STREAM TROUGH OVER
NORTHWEST ONTARIO IS SHIFTING TOWARD LAKE SUPERIOR. THE DYNAMICS
AND 850-700MB MOISTURE TRANSPORT ASSOCIATED WITH THESE FEATURES
WILL CONTINUE SHIFTING EAST OF THE FORECAST AREA DURING THE LATE
AFTERNOON AND EARLY EVENING...WITH ONLY WIDELY SCATTERED SHOWERS
LINGERING OVER WEST CENTRAL WI AFTER DARK. CONCERN THEN SHIFTS TO
CLOUD COVER AND THE POTENTIAL FOR FOG DEVELOPMENT OVERNIGHT.
SURFACE COLD FRONT HAS ENTERED WEST/NORTH CENTRAL MN
TODAY...ALTHOUGH IT WILL WASH OUT PRIOR TO REACHING CENTRAL MN.
WHILE POST-FRONTAL DEWPOINTS ARE IN THE MID TO UPPER 40S...PRE-
FRONTAL DEWPOINTS BETWEEN 65 AND 70 DEGREES ARE COMMON THIS
AFTERNOON ACROSS THE CWFA. THEREFORE...GIVEN THE LIGHT WIND
FIELD...AREAS THAT ARE ABLE TO CLEAR OUT TONIGHT WILL BE
SUSCEPTIBLE TO FOG DEVELOPMENT. THIS APPEARS MOST LIKELY ACROSS
WEST CENTRAL MN. FOR SOUTH CENTRAL MN...SHORT RANGE
MODELS...INCLUDING THE RAP AND THE NAM...INDICATE STRATUS CLOUDS
WILL LIFT OUT OF IOWA OVERNIGHT...SO LOW CEILINGS WILL BE MORE OF
A CONCERN THERE.

ON SUNDAY...A FEW SHOWERS MAY BE LINGERING FROM NEAR EAU CLAIRE TO
LADYSMITH IN THE MORNING. AN OTHERWISE DRY DAY IS EXPECTED...AS THE
AREA REMAINS SANDWICHED BETWEEN THE HUDSON BAY CYCLONE AND THE
AMPLIFYING WESTERN RIDGE. AFTER MORNING FOG AND LINGERING LOW CLOUDS
CLEAR...TEMPERATURES WILL REBOUND INTO THE LOW/MID 80S DURING THE
AFTERNOON UNDER MOSTLY SUNNY SKIES AND LIGHT WEST/SOUTHWEST WINDS.

THE MAIN WEATHER HEADLINE FOR THE UPCOMING WEEK WILL BE VERY WARM
TEMPERATURES...AS THE WESTERN RIDGE EXPANDS INTO THE CENTRAL UNITED
STATE. BY MID WEEK...TEMPERATURES WILL BE AROUND 15 DEGREES ABOVE
NORMAL...WITH HIGHS IN THE UPPER 80S TO LOWER 90S COMMON FROM
TUESDAY THROUGH THURSDAY. STILL CAN/T RULE OUT AN ARBITRARY SHOWER OR
THUNDERSTORM...BUT NO ORGANIZED PRECIPITATION IS ANTICIPATED THROUGH
NEXT WEEK.

THE RIDGE IS EXPECTED TO FLATTEN TOWARD THE END OF THE WORK WEEK
INTO LABOR DAY WEEKEND AS A SHORTWAVE TROUGH TRACKS ACROSS THE
PACIFIC NORTHWEST. THE EVOLUTION OF TC ISAAC WILL COME INTO PLAY
HOWEVER...AND FACTOR INTO HOW MUCH OF A COOL DOWN WE WILL SEE NEXT
WEEKEND. FORECAST CONFIDENCE AFTER FRIDAY IS THEREFORE RATHER LOW.

&&

.AVIATION.../00Z TAF ISSUANCE/
IFR/LIFR CIGS AND FOG THE MAIN CONCERN FOR THE MORNING. STRATUS AND
FOG DEVELOPING OVER WESTERN AREAS WHERE HIGHER CLOUDS CLEARED
EARLIER. SOME DRIER AIR OFF TO THE WEST...WORKING ALONG THE WESTERN
PERIPHERY...BUT BELIEVE WILL LIKELY SEE STRATUS CONTINUE TO DEVELOP
OVERNIGHT...WITH LOWERING VSBYS. FATHER EAST...MVFR CONDITIONS
SHOULD PREVAIL...BECOMING IFR 10Z-13Z. CONDITIONS IMPROVE BY 15Z MOST
AREAS WITH SUNSHINE EXPECTED WEST...PERHAPS SOME RESIDUAL CUMULUS
OVER THE EAST DURING THE DAY.  LIGHT SOUTH WINDS BECOMING WEST
DURING THE DAY SUNDAY. SHOULD REMAIN LESS THAN 10 KNOTS.

KMSP...WILL MENTION MVFR CONDITIONS DEVELOPING EARLY...POSSIBLY
BECOMING IFR CIGS AND PERHAPS VSBYS 10Z-12Z. EXPECT CONDITIONS TO
IMPROVE THROUGH 15Z WITH PERHAPS SOME RESIDUAL CUMULUS. LIGHT SOUTH
WINDS BECOMING SOUTHWEST AND EVENTUAL WEST BY NOON SUNDAY.  VFR
CONDITIONS WILL PREVAIL THROUGH THE REMAINDER OF THE PERIOD.

/OUTLOOK FOR KMSP/
MONDAY...VFR. WINDS NW AT 10 KTS.
TUESDAY...VFR. WINDS S AT 5KTS.
WEDNESDAY...VFR WITH POSSIBLE MVFR CLOUDS. WINDS SSW AT 10G15KTS.

&&

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

$$

LS/DE








AREA FORECAST DISCUSSION...UPDATED AVIATION

NWS ST LOUIS MO

 1202 AM CDT SUN AUG 26 2012

.UPDATE...
ISSUED AT 826 PM CDT SAT AUG 25 2012

REASONING PROVIDED BY PREVIOUS SHIFT STILL APPLIES. MAINLY
AFTERNOON DIURNALLY DRIVEN SHOWERS AND ISOLATED THUNDERSTORMS HAVE
DECREASED IN AREAL COVERAGE EARLY THIS EVENING. STILL BELIEVE THAT
AREA OF SHRA AND ISOLATED THUNDERSTORMS GETTING READY TO ENTER
WESTERN MO WILL CONTINUE TO PUSH EASTWARD TONIGHT WHICH WILL
INCREASE CHANCES OF RAIN AFTER MIDNIGHT. THIS AREA IS MAINLY
DRIVEN BY ASCENT FROM UPPER MIDWEST/CENTRAL PLAINS TROUGH. RAP IS
ALSO SHOWING AN IN INCREASE IN LOW LEVEL MOISTURE CONVERGENCE OVER
MUCH OF THE CWA AFTER MIDNIGHT AS LOW LEVEL JET INCREASES MOISTURE
TRANSPORT INTO THE AREA. THIS IS ALREADY HANDLED WELL BY GOING
FORECAST AND HAVE MADE ONLY MINOR TWEAKS IN TIMING THROUGH EARLY
TOMORROW. GOING POPS STILL LOOK GOOD FOR TOMORROW/TOMORROW NIGHT
AS TROUGH MOVES ACROSS THE CWA.

BRITT

&&

.SHORT TERM...
ISSUED AT 258 PM CDT SAT AUG 25 2012
(TONIGHT THROUGH MONDAY NIGHT)

BOUNDARY LAYER MOISTURE WILL CONTINUE TO INCREASE AHEAD OF A VERY
SLOW EASTWARD MOVING 500MB SHORTWAVE ACROSS KANSAS/OKLAHOMA THANKS
TO A 20-30KT LOW LEVEL JET. ISOLATED/SCATTERED CONVECTION POSSIBLE
TONIGHT IN THIS WARM ADVECTION REGIME...BUT COVERAGE SHOULD REMAIN
GREATEST WEST WHICH WILL BE CLOSER TO THE SHORTWAVE AND SURFACE
TROF. PWAT VALUES NEAR 2.0 INCHES SHOULD MAKE SOME VERY EFFECTIVE
RAIN PRODUCING SHOWERS/STORMS.

LOOK FOR HEAVIEST PRECIPITATION AXIS TO SLOWLY SHIFT EAST ACROSS THE
AREA ON SUNDAY AND SUNDAY NIGHT AS THE SHORTWAVE AND SURFACE
TROF/WEAK LOW MOVE ACROSS THE CWA. SUNDAY HIGH TEMPERATURES WILL
DEPEND ON CLOUD AND PRECIPITATION COVERAGE. THINKING THERE SHOULD BE
A GRADIENT FROM NORTHWEST(BELOW AVERAGE) TO SOUTHEAST(ABOVE
AVERAGE).

THUNDERSTORM CHANCES WILL SHIFT INTO THE SOUTHERN HALF OF THE CWA ON
MONDAY WITH THE SURFACE TROF/FRONT SETTLING SOUTHWARD. THE CHANCE OF
RAIN WILL END FOR THE ENTIRE AREA MON NGT AS HIGH PRESSURE BUILDS
SOUTH FROM THE UPPER MIDWEST.

CVKING

&&

.LONG TERM...
ISSUED AT 258 PM CDT SAT AUG 25 2012
(TUESDAY THROUGH SATURDAY)

AN UPPER LEVEL RIDGE WILL BUILD OVER THE REGION NEXT WEEK...WITH
A RETURN OF ABOVE NORMAL TEMPERATURES TO END THE MONTH OF AUGUST.
HAVE MY DOUBTS ON HOW MUCH IMPACT ISAAC WILL HAVE ON THE
FORECAST...EVEN WITH THE LATEST GFS RUN BRINGING THE REMNANTS
OVERHEAD BY THE END OF THE WORK WEEK AND NEXT WEEKEND. THIS TRACK
IS CLIMATOLOGICALLY NOT FAVORED...AS RECURVE OF THESE TROPICAL
SYSTEMS NORMALLY FAVORS A LANDFALL OF WESTERN LOUISIANA OR TEXAS
FOR OUR CWA TO SEE ANY IMPACT. HAVE FOLLOWED HPC GUIDANCE PRETTY
CLOSELY IN THE EXTENDED WHICH FAVORS A TRACK MUCH FURTHER EAST
AFTER LANDFALL SIMILAR TO THE 12Z ECWMF.

CVKING

&&

.AVIATION...
ISSUED AT 1156 PM CDT SAT AUG 25 20112

CHALLENGE IN THE FORECAST WILL BE TIMING OF THE PRECIPITATION WITH
THE WEAKENING UPPER LOW WHICH WILL MERGE WITH THE NORTHERN WAVE
THAT WILL DIVE INTO THE OHIO VALLEY MONDAY. PRECIP OVER WESTERM MO
SLOWLY MOVING EAST SO WILL TRY TO TIME ARRIVAL INTO COUN AND UIN
ACCORDINGLY. SCT AREAS OF MVFR CEILINGS ALSO FLOATING AROUND
CAUSING SOME PROBLEMS...ALTHOUGH COVERAGE IS LESS THAN GUIDANCE
INDICATES.

SPECIFICS FOR KSTL...SOME MVFR CLOUDS FLOATING AROUND BUT DO NOT
EXPECT THEM TO LAST SO MOSTLY VFR OVERNIGHT. EXPECT PRECIP TO MOVE
IN SLOWLY SUNDAY...INCREASE IN COVERAGE DURING THE
AFTERNOON...FALL APART SOME EARLY EVENING BEFORE THE UPPER TROF
AND WIDER COVERAGE ARRIVES BY 06Z SUNDAY. SHRA AND MVFR CEILINGS
POSSIBLE AFTER THAT TIME FRAME.

JPK

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







AREA FORECAST DISCUSSION

NWS NORTH PLATTE NE

 339 AM CDT SUN AUG 26 2012

.SHORT TERM...TODAY THROUGH WEDNESDAY

PRIMARY CONCERNS FOR THE FORECAST ARE THUNDERSTORM CHANCES THIS
AFTERNOON AND EVENING AND AGAIN MONDAY EVENING...AS WELL AS
TEMPERATURES. ALSO KEEPING AN EYE ON FIRE CONCERNS THROUGH THE
FIRST HALF OF THE WEEK.

WATER VAPOR IMAGERY THIS MORNING WAS SHOWING THE UPPER LEVEL
SHORTWAVE TROUGH WHICH PUSHED THE COLD FRONT ACROSS THE FORECAST
AREA ON SATURDAY LOCATED FROM CENTRAL KANSAS INTO WISCONSIN.
THE FRONT HAD STALLED OUT JUST TO THE EAST OF THE FORECAST AREA
AND HAD SINCE WASHED OUT...WITH HIGH PRESSURE NOW CENTERED OVER
WESTERN NEBRASKA. THE DEWPOINT GRADIENT REMAINS...WITH MOIST AIR
OVER EASTERN NEBRASKA /60 DEGREE DEWPOINTS ALONG AND EAST OF A KMCK
TO KBBW TO KONL LINE/...WITH VALUES IN THE 30S OVER THE NORTHERN
PANHANDLE. THUNDERSTORMS WERE ONGOING AHEAD OF THE SYSTEM...INTO
IOWA AND MISSOURI...WHILE STRATUS AND FOG WERE OBSERVED ACROSS
MUCH OF EASTERN NEBRASKA.

ONCE AGAIN LOOKING AT THE LARGE SCALE FLOW...THE UPPER LEVEL RIDGE
WAS CENTERED OVER THE SOUTHERN ROCKY MOUNTAIN RANGE. ALSO OF
NOTE...TROPICAL STORM ISAAC REMAINS A FOCAL POINT WITH THE CENTER
CURRENTLY MOVING OVER CUBA.

THE LOCAL FORECAST AREA IS RIGHT ON THE EDGE OF THE LOW LEVEL
MOISTURE AND FOG THIS MORNING. THE RAP SEEMS TO HAVE A GOOD HANDLE
ON THIS MOISTURE AND SHOWS IT DISSIPATING BY 16Z. WITH THE
PLACEMENT OF THE MOISTURE...AND THAT THE MODELS ARE PUSHING THE
SURFACE LOW INTO THE PANHANDLE TO TIGHTEN THE PRESSURE GRADIENT
AND INCREASE THE WIND...THIS SEEMS LIKE A GOOD SOLUTION AND WILL
FOLLOW THIS LEAD INTO THE FORECAST FOR TODAY. WITH THE EARLY
DISMISSAL OF THE CLOUDS...AND RETURN FLOW...WOULD EXPECT STRONG
WARMING TODAY. TEMPERATURES DO WARM A FEW DEGREES ALOFT FROM WHAT
WAS OBSERVED ON SATURDAY...ALTHOUGH SOUNDINGS ARE INDICATING FULL
MIXING WON/T BE REALIZED. HOWEVER WITH THE EXTRA HOURS OF
SUNSHINE...BELIEVE 90S ARE ATTAINABLE FOR TODAY IN MOST LOCATIONS.

AN UPPER LEVEL SHORTWAVE TROUGH WAS OBSERVED EARLY THIS MORNING
MOVING INTO WYOMING. THIS ENERGY WILL BE THE FOCUS FOR
THUNDERSTORM DEVELOPMENT LATER TODAY. ALTHOUGH THE RETURN FLOW
DOESN/T LOOK PARTICULARLY STRONG UNTIL LATER THIS EVENING...BOTH
THE NAM AND GFS INCREASE PRECIPITABLE WATER TO VALUES OF AN INCH
OR MORE /120 PERCENT OF NORMAL/ OVER THE PANHANDLE /JUST FOR
REFERENCE THE 26.00Z LBF SOUNDING OBSERVED PW OF 0.67...WHILE RAP
HAD 0.43/. EVEN IF THE MOISTURE DOESN/T INCREASE THIS MUCH...THERE
SHOULD BE ENOUGH TO ALLOW FOR ISOLATED THUNDERSTORMS TO DEVELOP
OVER THE PANHANDLE LATER THIS AFTERNOON. SOUNDINGS SHOWING
INVERTED-V PROFILE SO WILL CONTINUE TO SEE THE THREATS FOR STRONG
AND ERRATIC WINDS FROM ANY STORMS...AS WELL AS LOW RAINFALL
AMOUNTS AND A CHANCE FOR SOME STRAY DRY LIGHTNING STRIKES. GOING
EASTWARD...MOISTURE INCREASE ISN/T AS SUBSTANTIAL...AND WITH LARGE
SCALE FORCING BEING LESS...THESE AREAS WILL STAY CAPPED SO WILL
KEEP AREAS EAST OF A LINE FROM NORTH PLATTE TO AINSWORTH DRY.

MONDAY WILL BE A SIMILAR DAY TO SUNDAY...WITH STRONG WARMING
EXPECTED WITH LOTS OF SUNSHINE AND HIGHS IN THE 90S. ALTHOUGH THE
RIDGE WILL BUILD INTO THE PLAINS THROUGH THE DAY...A DECENT
SHORTWAVE TROUGH IS SIGNALED TO PUSH OVER THE RIDGE AND INTO
NEBRASKA IN THE AFTERNOON. THIS SIGNAL WAS BEING PICKED UP BY THE
ECMWF/NAM/GEM-REGIONAL/SREF...AND WITH THE PROPER PLACEMENT OF THE
RIDGE...FELT IT WAS FITTING TO ADD A SLIGHT CHANCE OVER TH
PANHANDLE AND FAR NORTHWEST NEBRASKA.

TUESDAY AND WEDNESDAY SHOULD BE DRY...WITH THE UPPER LEVEL RIDGE
IN PLACE OVER THE HIGH PLAINS AND LOW PRESSURE AT THE SURFACE OFF
TO THE WEST. WINDS WILL BE BREEZY FROM THE SOUTH BOTH
DAYS...HOWEVER ALL MODELS ARE IN AGREEMENT WITH KEEPING MOISTURE
LIMITED...WITH DEWPOINTS IN THE 40S AND 50S. THE LACK OF MOISTURE
ADVECTION LIKELY HAS SOMETHING TO DO WITH TROPICAL STORM ISAAC
/LIKELY HURRICANE ISAAC BY THIS TIME/ TAKING MUCH OF THE AVAILABLE
MOISTURE. TUESDAY LOOKS TO BE THE WARMEST DAY OF THE WEEK...WITH
MID TO UPPER 90S EXPECTED...WITH WIDESPREAD 90S FOR WEDNESDAY AS
WELL.

FIRE WEATHER CONCERNS WILL BE ON THE FOREFRONT MONDAY THROUGH
WEDNESDAY...WITH THE COMBINATION OF THE DRY AIR AND BREEZY WINDS.
ALTHOUGH THE CURRENT FORECAST WOULD KEEP CONDITIONS OUT OF
CRITICAL CRITERIA...THE EXTREME DRYNESS OF THE FUELS COULD CAUSE
THE NEED FOR RED FLAG WARNINGS IF CONDITIONS ARE EXPECTED TO BE
CLOSE.

.LONG TERM...THURSDAY THROUGH SATURDAY

THE UPPER LEVEL RIDGE HOLDS STRONG THROUGH THE SECOND HALF OF THE
WEEK. THIS WILL KEEP TEMPERATURES WARM AND ABOVE NORMAL IN THE
90S...WITH LITTLE IF ANY CHANCES FOR RAIN. AS THE RIDGE SHIFTS
EAST...COULD GET PACIFIC MOISTURE TO PUSH INTO THE NORTHERN AND
CENTRAL PLAINS...HOWEVER MODELS ARE NOT INDICATING ANY UPPER LEVEL
SUPPORT FOR ANY SHOWER OR STORM DEVELOPMENT SO KEPT THE FORECAST
DRY. IN TURN...THE STRENGTH OF THE RIDGE WILL LIKELY KEEP ANY
MOISTURE FROM ISAAC WELL EAST OF THE PLAINS. THERE HAS BEEN
CONSIDERABLE DIFFERENCES IN WHERE THE SYSTEM WILL TRACK ONCE
COMING ON-SHORE BUT AGAIN BECAUSE OF THE RIDGE OVER THE
PLAINS...IT WILL PROBABLY MOVE NORTH INTO THE OHIO RIVER VALLEY OR
EVEN ALONG THE EAST COAST.

&&

.AVIATION...

SOME PATCHY FOG DEVELOPING OVER NORTH CENTRAL NEBRASKA EARLY THIS
MORNING. MAIN AREA OF CONCERN WILL BE FROM KBBW TO KONL BUT
VISIBILITIES ALONG THE PLATTE RIVER VALLEY MAY BE REDUCED TO MVFR
AROUND SUNRISE. SOME ISOLATED THUNDERSTORMS MAY DEVELOP OVER THE
NEBRASKA PANHANDLE AND MOVE INTO THE WESTERN NEBRASKA SANDHILLS THIS
EVENING. ACTIVITY WILL STAY TO THE WEST OF A LINE FROM KVTN TO KLBF.
STRONG ERRATIC WINDS CAN BE EXPECTED IN THE VICINITY OF
THUNDERSTORMS.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM/EXTENDED...BROOKS
AVIATION...POWER







AREA FORECAST DISCUSSION

NWS SAN ANGELO TX

 1113 PM CDT SAT AUG 25 2012

.DISCUSSION...
SEE AVIATION DISCUSSION BELOW...

&&

.AVIATION...
SCATTERED SHOWERS AND THUNDERSTORMS CONTINUE ACROSS MAINLY THE BIG
COUNTRY THIS EVENING. I INCLUDED A TEMPO GROUP FOR THUNDER AT
KABI...AS A LINE OF THUNDERSTORMS WILL LIKELY SKIRT THE NORTHERN
PARTS OF THE CITY IN THE NEXT HOUR TO HOUR AND A HALF.
OTHERWISE...EXPECT SOUTH SOUTHEAST WINDS OF 6 TO 12 KNOTS TO
CONTINUE AT ALL TAF SITES OVERNIGHT. SCATTERED SHOWERS AND
THUNDERSTORMS WILL ONCE AGAIN BE POSSIBLE SUNDAY AFTERNOON...AND
I HAVE INCLUDED VCTS AT BOTH KABI AND KSJT...WHERE THE BEST CHANCE
OF CONVECTION EXISTS. OTHERWISE...VFR CONDITIONS WILL PREVAIL
THROUGH THE NEXT 24 HOURS.

&&

.PREV DISCUSSION... /ISSUED 944 PM CDT SAT AUG 25 2012/

UPDATE...
SENT A QUICK UPDATE OUT FOR THE FORECAST PACKAGE WITH MINOR
CHANGES MADE TO OVERNIGHT LOWS...WINDS AND SKY COVER.

DISCUSSION...
A COMPLEX OF WEAKLY ORGANIZED STORMS CONTINUES TO MOVE SLOWLY TO
THE EAST ACROSS THE WESTERN BIG COUNTRY...GENERALLY WEST OF A TYE
TO HASKELL LINE AS OF 930 PM. MODEST LARGE SCALE ASCENT WAS NOTED
ON THE WATER VAPOR LOOP IN RESPONSE TO A SHORTWAVE TROF OVER
SOUTHEAST NM. INSTABILITY LOOKS TO BE RATHER LIMITED...AT LEAST
BASED ON RAP DEPENDENT MESO ANALYSIS...WITH AN AREA OF MUCAPE
VALUES AROUND 1000 J/KG OVER THE AREA CURRENTLY EXPERIENCING
CONVECTION. EFFECTIVE SHEAR VALUES IN THE 25-30 KT RANGE SUGGEST
THAT MULTICELLULAR MODE MAY BE SUSTAINED FOR SEVERAL MORE
HOURS...ESPECIALLY AS THE LOW LEVEL JET DEVELOPS DURING THE
OVERNIGHT HOURS. WE COULD SEE ADDITIONAL CONVECTIVE DEVELOPMENT...
MAINLY SHOWERS...OVER THE HEARTLAND OVERNIGHT. INHERITED POPS WERE
LEFT INTACT WITH MINOR CHANGES MADE TO WINDS...SKY COVER AND
OVERNIGHT LOW TEMPS.

JOHNSON

PREV DISCUSSION... /ISSUED 603 PM CDT SAT AUG 25 2012/

DISCUSSION...
SEE AVIATION DISCUSSION BELOW...

AVIATION...
ISOLATED SHOWERS AND THUNDERSTORMS CONTINUE ACROSS THE AREA. I
LEFT IN A MENTION OF VCTS AT KABI...KSJT AND KBBD WHERE THE BEST
CHANCE OF SEEING A THUNDERSTORM EXISTS. BRIEF MVFR CONDITIONS WILL
BE POSSIBLE WITHIN ANY THUNDERSTORMS. MOST OF THIS ACTIVITY SHOULD
BEGIN TO DISSIPATE BY 02Z. SOUTH SOUTHEAST WINDS WILL REMAIN LIGHT
OVERNIGHT. A WEAK COLD FRONT IS FORECAST TO MOVE INTO THE NORTHERN
BIG COUNTRY SUNDAY AFTERNOON...WITH ISOLATED TO SCATTERED SHOWERS
AND THUNDERSTORMS DEVELOPING. I WENT AHEAD AND INCLUDED A VCTS
GROUP AFTER 19Z AT BOTH KABI AND KSJT WHERE THE BEST CHANCE OF
SEEING CONVECTION LIES. OTHERWISE...EXPECT VFR CONDITIONS TO
PREVAIL THROUGH THE NEXT 24 HOURS.

PREV DISCUSSION... /ISSUED 337 PM CDT SAT AUG 25 2012/

SHORT TERM...
CLOUD COVER ASSOCIATED FROM SHOWERS LAST NIGHT HAS LARGELY
DISSIPATED THIS AFTERNOON...AND WITH MORE SUNSHINE AND RAPIDLY
WARMING TEMPERATURES...HAVE STARTED TO SEE CONVECTION DEVELOP. SO
FAR...THE STORMS HAVE REMAINED ALONG THE WESTERN BORDER OF THE
AREA...WHERE THE MODELS HAVE SHOWN THE LOW TO MID LEVEL THETA E
AXIS TO REMAIN. GIVEN THE FAIRLY UNSTABLE...RELATIVELY UNCAPPED
AIR MASS...IN PLACE CANT REALLY RULE OUT A STORM JUST ABOUT
ANYWHERE. BUT BEST CHANCES LOOK TO BE ACROSS THE NORTHERN AND
WESTERN BIG COUNTRY...WITH THE CONVECTION EVENTUALLY SETTLING INTO
THE INTERSTATE 20 CORRIDOR THIS EVENING. THIS IDEA WELL CORRELATED
WITH THE TTU WRF AS WELL...SO SOME CONFIDENCE IN THIS SCENARIO.

WEAK FRONTAL BOUNDARY DROPS THROUGH THE PANHANDLE AND INTO THE BIG
COUNTRY BY SUNDAY AFTERNOON. CONVERGENCE WILL LIKELY BE PRETTY
WEAK...BUT AGAIN...GIVEN THE AIR MASS IN PLACE...WONT TAKE MUCH.
TTU WRF AGAIN SHOWS A FEW STORMS SUNDAY AFTERNOON ACROSS THE
AREA...MAINLY ALONG THE FRONT...WHERE THE GFS IS ALSO SHOWING THE
BEST LOW LEVEL THETA E AXIS. WILL USE THIS AS A BASIS FOR THE
SUNDAY POP FORECAST.

LONG TERM...
RETAINING SLIGHT CHANCE POPS THROUGH MONDAY. UPPER HIGH WILL BUILD
EARLY NEXT WEEK OVER COLORADO/NEW MEXICO WITH NORTH-NORTHEAST
FLOW ALOFT DEVELOPING OVER OUR AREA. THE GFS AND NAM SHOW A COUPLE
OF WEAK DISTURBANCES ALOFT MOVING DOWN INTO OUR AREA. AIRMASS
LOOKS TO REMAIN SUFFICIENTLY MOIST FOR THE POSSIBILITY OF ISOLATED
TO SCATTERED SHOWERS/THUNDERSTORMS. IN ADDITION...WITH A SURFACE
HIGH BUILDING INTO THE MIDWEST AND CENTRAL PLAINS...COULD HAVE A
WEAK COLD FRONTAL BOUNDARY SAGGING SOUTH ACROSS OUR AREA ON
MONDAY. SURFACE CONVERGENCE ALONG THIS BOUNDARY WILL BE RATHER
WEAK... HOWEVER.

THOUGH THE TIMING IS UNCERTAIN...THE 12Z MODELS INDICATE THE
POTENTIAL FOR AN ADDITIONAL DISTURBANCE ALOFT TO DROP SOUTH-
SOUTHWEST INTO OUR WEST CENTRAL TEXAS ON TUESDAY...WITH AN
ATTENDANT INCREASE IN MOISTURE/PRECIPITABLE WATER. HAVE DECIDED TO
CARRY A SLIGHT CHANCE POP IN THE EAST-CENTRAL PART OF OUR AREA FOR
TUESDAY.

DRIER AIR IS PROGGED TO WORK ITS WAY SOUTH-SOUTHWEST INTO OUR AREA
BY LATE WEDNESDAY AND REMAIN OVER OUR AREA TO THE END OF THE WEEK.
THIS WILL RESULT IN LESS CLOUD COVER ACROSS OUR AREA. WITH LIGHT
WINDS AT NIGHT...THIS SHOULD ALSO ALLOW TEMPERATURES TO DROP INTO
THE MID TO UPPER 60S FOR LOWS THURSDAY AND FRIDAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
ABILENE  73  93  73  93  69 /  30  30  20  20  10
SAN ANGELO  74  94  73  96  70 /  20  20  20  20  10
JUNCTION  75  93  72  95  69 /  10  10  20  20  10

&&

.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

99/99/99






AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 234 AM CDT SUN AUG 26 2012

.SHORT TERM...THROUGH TUESDAY
234 AM CDT SUN AUG 26 2012

MAIN FORECAST CONCERN IS WITH THE RAIN CHANCES TODAY.

SURFACE ANALYSIS THIS MORNING SHOWED A WEAK AREA OF LOW PRESSURE
OVER NORTHEAST KANSAS WITH A TROUGH OF LOW PRESSURE EXTENDING
NORTHEAST INTO CENTRAL WISCONSIN. LOCAL AND REGIONAL RADARS WERE
SHOWING SHOWERS OCCURRING ALONG AND AHEAD OF THE TROUGH FROM
NORTHEAST WISCONSIN INTO WESTERN MISSOURI.

THE LAST SHORT WAVE TROUGH ASSOCIATED WITH THE REMAINS OF THE
CENTRAL ROCKIES UPPER LEVEL LOW WAS OVER EASTERN KANSAS THIS
MORNING WITH THE SURFACE LOW. THIS SHORT WAVE TROUGH IS EXPECTED
TO CONTINUE MOVING NORTHEAST TOWARD LOWER MICHIGAN TODAY. THE WEAK
AREA OF LOW PRESSURE AT THE SURFACE SHOULD TRACK SOUTH OF THE AREA
REACHING THE SOUTHERN PORTION OF LAKE MICHIGAN LATE THIS
AFTERNOON. AS THE LOW AND SHORT WAVE TROUGH PASS BY...THE FORCING
WILL BE EXITING THE AREA WITH THE 26.12Z NAM SHOWING THE WEAK
FRONTOGENESIS ALONG THE TROUGH OF LOW PRESSURE IN THE 1000-850 MB
LAYER SHIFTING EAST OF THE AREA THIS AFTERNOON AND EVENING. THE
WEAK ISENTROPIC UP GLIDE ON THE 310K SURFACE WILL PUSH OFF TO THE
EAST THIS MORNING AS WILL THE BEST MOISTURE TRANSPORT. EXPECT THE
SHOWERS TO CONTINUE MOVING EAST WITH THE BETTER FORCING WITH THE
BEST COVERAGE THIS MORNING OVER THE SOUTHEAST SECTIONS. THE
WESTERN SECTIONS OF THE FORECAST AREA ALREADY LOOK TO BE DONE AND
HAVE REMOVED THE RAIN CHANCES FOR THOSE AREAS. BY AFTERNOON...MOST
OF THE AREA SHOULD BE DRY WITH SOME LINGERING CHANCES ACROSS THE
SOUTHEAST SECTIONS.

HIGH PRESSURE WILL BUILD IN OVER THE AREA TONIGHT ALLOWING THE
SKIES TO CLEAR OUT DURING THE EVENING. THE NAM BUFKIT SOUNDING FOR
KLSE SUGGESTS A STRONG POSSIBILITY OF VALLEY FOG FORMING WITH
LIGHT WINDS UP THROUGH ABOUT 3 THOUSAND FEET AND SATURATION
OCCURRING AT THE SURFACE. IT DOES HAVE A RATHER LARGE TEMP/DEW
POINT SPREAD THIS EVENING BUT THIS SEEMS TO BE BECAUSE IT CREATES
TOO MUCH MIXING THIS AFTERNOON AND LOWERS THE DEW POINT TOO MUCH.
THE 26.04Z RAP SOUNDING DOES NOT SHOW NEARLY AS MUCH MIXING AND
DRYING THIS AFTERNOON SO MORE MOISTURE SHOULD BE IN PLACE THIS
EVENING TO AID IN THE FOG FORMATION. THE HIGH THEN LOOKS TO REMAIN
IN PLACE OVER THE REGION THROUGH TUESDAY WITH MODERATING
TEMPERATURES PUSHING DAYTIME READINGS BACK ABOVE NORMAL.

.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY
234 AM CDT SUN AUG 26 2012

ANY RAIN CHANCES IN THE EXTENDED WILL DEPEND ON THE EVENTUAL PATH
OF TROPICAL STORM ISAAC. THE DIFFERENCES BETWEEN THE 26.00Z GFS
AND 25.12Z ECMWF ARE QUITE LARGE AND WHILE THE GFS NORMALLY DOES A
BETTER JOB OF HANDING TROPICAL SYSTEMS OVER THE OPEN
WATERS...CONFIDENCE ON HOW IT HANDLES THE SYSTEM ONCE IT IS INLAND
IS PRETTY LOW. THE UPPER LEVEL RIDGE IN PLACE AHEAD OF ISAAC
SHOULD REMAIN OVER THE MIDWEST UNTIL LATE IN THE WEEK KEEPING THE
AREA DRY. ALL THE MODELS SUGGEST A NORTHERN STREAM SYSTEM WILL
MOVE ONTO THE PACIFIC NORTHWEST COAST THURSDAY BUT THEN DIFFER ON
HOW FAST THIS MOVES EAST. THE GFS IS THE FASTEST AS IT USES THIS
SYSTEM AS THE KICKER TO RECURVE ISAAC. THE ECMWF IS MUCH SLOWER
WITH THIS SYSTEM AND FARTHER NORTH AS WELL. FOR NOW...PLAN TO
MAINTAIN CONTINUITY WITH THE PREVIOUS FORECAST AND KEEP THE
EXTENDED PERIOD DRY AND WARM.

&&

.AVIATION...THROUGH 06Z MONDAY
1148 PM CDT SAT AUG 25 2012

SOUTH TO SOUTHEASTERLY LOW LEVEL FLOW KEPT DRY AIR IN PLACE AT
BOTH TAF SITES LAST EVENING...MAINTAINING THE VFR CONDITIONS. THIS
IS DESPITE SHOWERS MOVING ACROSS ASSOCIATED WITH A LOW PRESSURE
SYSTEM LIFTING NORTHEAST OUT OF KANSAS. THESE SHOWERS ARE EXPECTED
TO PERSIST OFF AND ON AT KLSE...LIKELY TO 16Z...BEFORE THE SYSTEM
MOVES FAR ENOUGH EAST TO END THE RAIN. EVENTUALLY THE SHOWERS WILL
END UP LOWERING THE CEILING...ANTICIPATED TO DROP TO MVFR BY 12Z.
VISIBILITIES MAY DROP TO MVFR SOONER...AROUND 10Z. MEANWHILE...AT
KRST...THE CLOUDS ROOTED AT 12000-15000 FT AGL ARE SHOWING SIGNS
OF THINNING ON SATELLITE IMAGERY. IN ADDITION...THERE IS A
COLLECTION OF MVFR/IFR STRATUS SITUATED FROM NORTHWEST IOWA TO THE
TWIN CITIES...LOCATED ON/BEHIND A TROUGH OF LOW PRESSURE. ONE OF
TWO THINGS COULD HAPPEN AT KRST: 1. THE MVFR/IFR STRATUS MOVES IN
AS THE TROUGH CROSSES THE TAF SITES. 2. THE CURRENT ALTOSTRATUS
CLEARS OUT...RESULTING IN POSSIBLY DENSE FOG DEVELOPMENT DUE TO
RECENT RAIN AND HIGH AMOUNT OF SURFACE MOISTURE. FOR NOW HAVE
MAINTAINED CONTINUITY WITH THE PREVIOUS FORECAST SINCE EITHER
SCENARIO IS POSSIBLE...WITH THE IDEA OF IFR BR/STRATUS DEVELOPING
BY 10Z. GIVEN THE UNCERTAINTY...AMENDMENTS MAY BE NEEDED TO THE
KRST TAF.

THE COMBINATION OF DAYTIME HEATING AND DRIER AIR OVER THE DAKOTAS
SLOWLY MOVING EAST WILL ALLOW CONDITIONS TO TURN VFR AT BOTH TAF
SITES BY 19-20Z TODAY. VFR CONDITIONS ARE EXPECTED TO PERSIST
THROUGH THE EVENING WITH HIGH PRESSURE IN PLACE. AFTER
06Z MONDAY...VALLEY FOG APPEARS LIKELY TO FORM AT KLSE. THIS WILL
BE ADDRESSED MORE IN THE NEXT AVIATION DISCUSSION.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
234 AM CDT SUN AUG 26 2012

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

&&

$$

SHORT TERM...04
LONG TERM...04
AVIATION...AJ








AREA FORECAST DISCUSSION

NWS LINCOLN IL

 910 AM CDT SUN AUG 26 2012

.DISCUSSION...
ISSUED 910 AM CDT SUN AUG 26 2012

SHORT-WAVE TROUGH EVIDENT ON WATER VAPOR IMAGERY OVER EASTERN
KANSAS/OKLAHOMA WILL BE THE PRIMARY FOCUSING MECHANISM FOR SHOWERS
AND THUNDERSTORMS TODAY INTO TONIGHT. LEAD WAVE HAS TRIGGERED
SCATTERED SHOWERS ACROSS THE AREA THIS MORNING...HOWEVER THESE
ARE RAPIDLY LIFTING NORTHWARD AND SHOULD CLEAR MUCH OF THE KILX
CWA WITHIN THE NEXT COUPLE OF HOURS. AFTER A BRIEF LULL IN THE
PRECIP...HIGH-RES MODELS SUCH AS THE HRRR DEVELOP ADDITIONAL
CONVECTION ACROSS WEST-CENTRAL ILLINOIS INTO MISSOURI BY MID TO
LATE AFTERNOON. WITH FORECAST SOUNDINGS INDICATING CAPE VALUES OF
1000 TO 1500J/KG...A FEW STRONG STORMS COULD DEVELOP. MAIN THREATS
FROM ANY STORMS LATER TODAY WILL BE GUSTY WINDS AND HEAVY
DOWNPOURS. HAVE ADJUSTED THE FORECAST TO BETTER ACCOUNT FOR
CURRENT TRENDS. HAVE REMOVED THUNDER MENTION DURING THE
MORNING...AND FOCUSED BEST CHANCES FOR CONVECTION THIS AFTERNOON
ALONG/WEST OF I-55. SHOWERS/STORMS WILL THEN SPREAD FURTHER
EASTWARD INTO EAST-CENTRAL ILLINOIS TONIGHT...AS THE UPPER WAVE
AND ASSOCIATED COLD FRONT MOVE ACROSS THE AREA.

BARNES
&&

.AVIATION...
ISSUED 642 AM CDT SUN AUG 26 2012

MVFR CEILINGS STARTING TO SPREAD IN FROM THE WEST...WITH MAINLY
KPIA AFFECTED AT THE MOMENT. SHOULD SLOWLY SEE THESE OVERSPREAD
THE REMAINDER OF THE TAF SITES AS THE MORNING PROGRESSES. LATEST
MODEL GUIDANCE SHOWING SOME POTENTIAL FOR THESE TO RISE AGAIN THIS
AFTERNOON. SHOWERS HAVE BEGUN TO INCREASE IN COVERAGE AS OF
LATE... ALTHOUGH MAIN PRECIPITATION SHIELD STILL FURTHER WEST FROM
SOUTHWEST MISSOURI INTO EAST CENTRAL IOWA. THIS WILL MOVE INTO THE
AREA LATER THIS MORNING. HAVE NOT SEEN MUCH IN THE WAY OF
LIGHTNING ACTIVITY SO FAR...BUT GUIDANCE SUGGESTING THE POTENTIAL
SHOULD INCREASE LATE MORNING INTO AFTERNOON...SO HAVE INTRODUCED
VCTS AT ALL SITES.

MAIN COLD FRONT EXPECTED TO CROSS THE TAF SITES IN THE 09-12Z TIME
FRAME. GIVEN THE RAIN THAT WILL BE OCCURRING LATER TODAY...HAVE
SOME CONCERNS THAT LOW CLOUDS AND FOG COULD DEVELOP BY THE TIME
OF FRONTAL PASSAGE. SREF GUIDANCE INDICATES AREAS FROM KBMI/KPIA
NORTHWEST ARE MOST SUSCEPTIBLE...AND HAVE INTRODUCED SOME IFR
CEILINGS LATE IN THE FORECAST PERIOD AT THESE SITES.

GEELHART
&&

.PREV DISCUSSION...
ISSUED 302 AM CDT SUN AUG 26 2012

07Z SURFACE ANALYSIS INDICATED A 1011 MB LOW NEAR TOPEKA WITH A WARM
FRONT ARCING NORTHEAST NEAR THE IA/MO BORDER. LOW 70S DEWPOINTS
HAD ADVECTED NORTH TO THIS BOUNDARY. AT THE MID LEVELS...00Z U/A
ANALYSIS AND WATER VAPOR IMAGERY SHOWED A SLOW MOVING SHORTWAVE TROUGH
AXIS OVER EASTERN KS. REGIONAL RADAR MOSAICS INDICATED WIDESPREAD
RAIN AND EMBEDDED THUNDER SHIFTING NORTHEAST FROM WESTERN MO INTO
SOUTHERN IA...ASSOCIATED WITH THESE SFC AND UPPER FEATURES.
LOCALLY...BROAD ELEVATED WARM MOIST ADVECTION WAS PRODUCING PLENTY
OF AC BUT NOT MUCH IN THE WAY OF SHOWERS YET. MAIN FORECAST ISSUE IS
RAINFALL TIMING/COVERAGE/AMOUNTS TODAY INTO MONDAY AS THE SYSTEM
SHIFTS ACROSS THE CWA.

SHORT TERM...TODAY THROUGH MONDAY

MOISTURE ADVECTION AHEAD OF THE MID LEVEL TROUGH WILL BRING A
VERY MOIST AIR MASS INTO THE CWA TODAY AND TONIGHT. W/V IMAGERY
SHOWS A MID-LEVEL TROPICAL/PACIFIC MOISTURE PLUME WELL
ENTRAINED INTO THIS SYSTEM...WHILE LLVL FLOW HAS BROUGHT GULF MOISTURE
AND ASSOCIATED 70+ DEWPOINTS NORTH INTO THE MIDWEST. WITH THESE
FACTORS IN PLACE IT IS NOT SURPRISING TO SEE 2.0-2.2 INCH
PRECIPITABLE WATER VALUES ON FORECAST SOUNDINGS AND NUMERICAL
MODEL OUTPUT. SUCH NUMBERS ARE NEAR THE 99TH PERCENTILE FOR LATE
AUGUST...OR 175 PERCENT OF NORMAL. WITH BROAD ISENTROPIC LIFT IN
PLACE...WAVES OF ADDITIONAL FORCING ASSOCIATED WITH 850-500 MB
TROUGHS AND SHORTWAVE ENERGY WILL BRING SEVERAL ROUNDS OF SHOWERS
AND EMBEDDED THUNDERSTORMS TO THE CWA TODAY AND TONIGHT. HIGHEST
QPF VALUES REMAIN FOCUSED ON THE WESTERN HALF OF THE CWA WHERE
LIFT IS MAXIMIZED THIS AFTERNOON AND EVENING. WIDESPREAD HALF TO
ONE INCH AMOUNTS FROM EAST TO WEST NOW LOOK LIKELY BY MONDAY
MORNING. SOME SIGNS THAT TRAINING OF CONVECTION COULD PRODUCE
ISOLATED 2 INCH AMOUNTS ESPECIALLY NEAR THE NW CWA. PRIMARY
SHORTWAVE WEAKENS AS IT CROSSES THE MISSISSIPPI RIVER THIS
EVENING...LEADING TO LIGHTER TOTALS AND LESS COVERAGE SHOWERS
OVERNIGHT. 00Z MODELS HAVE CONTINUED THE TREND FROM 12Z OF SLOWING
SYSTEM EXIT TO THE EAST AND WILL KEEP CHANCE POPS FOR THE
SOUTHEAST HALF INTO MONDAY AFTERNOON...THOUGH MOST ORGANIZED RAINS
SHOULD BE DISSIPATING BY THEN. DRIER AIR FILTERING IN ON NORTH
WINDS BRING CLEARING SKIES FROM THE NORTH MONDAY AFTERNOON.

AS FAR AS TEMPERATURES ARE CONCERNED...THICK CLOUD COVER AND
OCCASIONAL RAIN MAY KEEP THE NW CWA IN THE UPPER 70S TODAY...WHILE
THE FAR SE COULD SEE ENOUGH SUN AND DRY HOURS TO GET INTO THE UPPER
80S. MONDAY...SUNNIER LOCATIONS IN THE NORTHWEST SHOULD REBOUND
WELL INTO THE UPPER 80S AS COLD ADVECTION IS NON-EXISTENT BEHIND
THE FRONT. CLOUDS LINGERING THROUGH MUCH OF THE AFTERNOON COULD
KEEP PARTS OF THE E/SE IN THE LOWER 80S.

LONG TERM...TUESDAY THROUGH SATURDAY

AN IDEAL STRETCH OF LATE SUMMER WEATHER LOOKS TO SET UP ACROSS THE
AREA FOR MUCH OF THE WEEK...AS SURFACE AND UPPER RIDGING BUILD
OVER THE MIDWEST. THIS WILL PRODUCE MOSTLY CLEAR SKIES...LIGHT
WINDS...AND SEASONABLY LOW HUMIDITY. THIS DRY AIR WILL ALLOW FOR
LARGE DIURNAL TEMPERATURE SWINGS WITH LOWS MAINLY IN THE LOW/MID
60S AND HIGHS IN THE MID 80S TO LOWER 90S. ANY HOPES FOR RAIN WILL
HINGE ON THE EVENTUAL PATH OF ISAAC REMNANTS FOR THE
FRIDAY/SATURDAY TIME FRAME. TO SAY MODEL AGREEMENT IS POOR WOULD BE
AN UNDERSTATEMENT...AND WILL CONTINUE TO KEEP POPS BELOW
MENTIONABLE LEVELS.

25

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$








AREA FORECAST DISCUSSION

NWS QUAD CITIES IA IL

 640 AM CDT SUN AUG 26 2012

.AVIATION...
A WEAK LOW PRESSURE SYSTEM WILL BRING PERIODS OF RAINFALL TO THE
LOCAL AREA TODAY AND INTO TONIGHT. CIGS AND VSBYS WILL BE BELOW
MVFR THRESHOLDS FOR MUCH OF TODAY AND WILL DROP BELOW IFR THRESHOLDS
DURING PERIODS OF RAIN. ONCE THE RAIN ENDS TONIGHT...LIGHT WINDS
WILL FOLLOW AND THERE IS POTENTIAL FOR FOG TO DEVELOP IN THE EARLY
MORNING HOURS. DMD

&&

.PREV DISCUSSION... /ISSUED 338 AM CDT SUN AUG 26 2012/

SYNOPSIS...
WEAK UPPER LEVEL WESTERLY FLOW CONTINUES OVER NEARLY ALL OF THE
CONUS. CORRESPONDINGLY WEAK 500MB TROUGH SPANS THE PLAINS FROM
SOUTHERN MINNESOTA INTO WEST TEXAS. PLUME OF LOW LEVEL MOISTURE IS
FEEDING FROM THE GULF OF MEXICO INTO THE UPPER MIDWEST...WITH 850MB
DEW POINTS AT OR ABOVE 15C OVER A SIGNIFICANT PORTION OF THE
SOUTHERN PLAINS AND LOWER MS VALLEY. AT THE SURFACE...LOW PRESSURE
IS CENTERED OVER KANSAS CITY THIS MORNING WITH A TROUGH EXTENDING TO
ITS SOUTHWEST...AND THE BEGINNINGS OF A WEAK WARM FRONT DEVELOPING
ACROSS NORTHERN MISSOURI AND SOUTHERN ILLINOIS.

SHORT TERM...TODAY AND TONIGHT...
FIRST WAVE OF SHOWERS ONGOING THIS MORNING OVER NORTHERN PORTIONS OF
THE CWFA...IN A BROAD AREA OF MID LEVEL ISENTROPIC LIFT AROUND
305K.  MAIN SHOW DRIVEN BY THE UPPER TROUGH IS NOW KNOCKING ON OUR
DOOR OVER SOUTHCENTRAL IOWA.  PRECIPITABLE WATERS ABOVE 2
INCHES...ABOUT 175 PERCENT OF NORMAL...OVER THE ENTIRE CWFA THIS
MORNING SUGGEST HIGHLY EFFICIENT RAINFALL PROCESSES. GIVEN THE WEAK
UPPER FLOW...SYSTEM WILL BE SLOW TO PROGRESS...FURTHER PADDING THE
RAINFALL TOTALS.  ALTHOUGH ONSET IS A BIT SLOWER THAN PREVIOUSLY
FORECAST...STILL LOOKS LIKE WE SHOULD SEE WIDESPREAD AMOUNTS NEAR
ONE INCH.  MID LEVEL LAPSE RATES SUGGEST POTENTIAL FOR WIDESPREAD
THUNDER IS LOW.  HOWEVER...ISOLATED EMBEDDED THUNDER HAS CONTINUED
OVERNIGHT OVER NORTHERN MISSOURI AND WILL MAINTAIN MENTION OF
ISOLATED THUNDER AS THE UPPER FORCING MOVES INTO THE AREA THIS
MORNING.

FAVORED THE RAP AND NAM TODAY AS BOTH HAVE A DECENT HANDLE ON THE
SURFACE FEATURES.  BASED ON THE NAM SOLUTION...BROAD SCALE LIFT
CONTINUES THROUGH MOST OF THE DAY AHEAD OF THE SURFACE LOW.  SHOULD
SEE PRECIP ENDING FROM WEST TO EAST LATE TODAY AND INTO TONIGHT AS
THE SYSTEM CLEARS THE AREA.

DMD

LONG TERM...MONDAY THROUGH NEXT SATURDAY...
MAINLY DRY WITH NEAR TO ABOVE NORMAL TEMPS AS SFC AND UPPER RIDGING
DOMINATES FOR MUCH OF THE PERIOD.

MON-WED... DRY AND FEW DEGS COOLER WITH LIGHT NORTHERLY WINDS TO
PERSIST FOR MUCH OF THE PERIOD VEERING TO EASTERLY BY WED AS SFC
HIGH SHIFTS THROUGH GREAT LAKES. H85 THERMAL GRADIENT W-E SHOWN
TO RESIDE OVER CWA WITH H85 TEMPS MAINLY IN RANGE OF 14-18C. THESE
VALUES MIXED TO SFC CLOSER TO DRY ADIABATICALLY SUPPORT WIDESPREAD
80S WITH COOLEST READINGS E/NE AND WARMEST S/SW. LOWS NEAR TO
BELOW COOLEST GUIDANCE WITH GOOD RADIATIONAL COOLING SETUP DURING
THE NIGHTS... WITH 50S FOR LOWS FAIRLY COMMON BOTH TUE AND WED AM.
DRY AIR SHOULD PROMOTE LARGE DIURNAL RANGES ON ORDER OF 30-35+ DEGS.

THU-SAT... UPPER LEVEL RIDGE BUILDS INTO REGION BY LATE WEEK AND THEN
FLATTENS. TEMPS ALOFT WARM WITH H85 TEMPS IN THE RANGE OF 20-25C.
BUT MODELS INDICATE WEAK MIXING REGIME WITH SFC RIDGE AXIS IN CLOSE
PROXIMITY... THUS NOT ABLE TO TAP FULL WARMTH AND SPARING US FROM
BAKING. THEREFORE... CONTINUATION OF MAINLY 80S FOR HIGHS. PCPN CHCS
LATE IN EXTENDED DEPENDENT ON MOVEMENT OF ISAAC REMNANTS.
OVERALL... HAVE SERIOUS DOUBTS THAT WE WILL SEE ANY IMPACT FROM
ISAAC DESPITE LATEST GFS AND GEM SOLUTIONS BRINGING REMNANTS
EITHER UP OVER CWA OR JUST GLANCING S/E CWA. TYPICALLY NEED LANDFALL
TO OCCUR IN TX OR WRN LA FOR THESE SYSTEMS TO HAVE ANY IMPACT
FOR OUR CWA. AT 06Z... GFS AND GEM WERE AROUND 3 MB TOO WEAK WITH
ISAAC AND THIS COULD AT LEAST PARTIALLY EXPLAIN THEIR MORE WESTERN
TRACK. IF WE SEE CONTINUED STRENGTHENING TDY TO HURRICANE THEN WOULD
EXPECT ISAAC TO START CURVING... AND IT WOULD SEEM VERY LIKELY THAT
ISAAC WOULD CONNECT WITH EASTERN TROUGH AND GET PULLED NORTHWARD.
THE KEY WILL BE AMOUNT/RATE OF INTENSIFICATION AS THE SLOWER ISAAC
TAKES TO RAMP UP THE MORE AND MORE A WESTERN TRACK WOULD BE POSSIBLE.
HAVE FOLLOWED HPC GUIDANCE CLOSELY LATE IN THE EXTENDED AND WILL HAVE
MAINLY DRY FCST FRI-SAT WITH ISAAC REMNANTS STAYING TO OUR E/SE.

MCCLURE

&&

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

$$








AREA FORECAST DISCUSSION

NWS QUAD CITIES IA IL

 636 AM CDT SUN AUG 26 2012

.AVIATION...
A WEAK LOW PRESSURE SYSTEM WILL BRING PERIODS OF RAINFALL TO THE
LOCAL AREA TODAY AND INTO TONIGHT. CIGS AND VSBYS BE BELOW MVFR
THRESHOLDS FOR MUCH OF TODAY AND WILL DROP BELOW IFR THRESHOLDS
DURING PERIODS OF RAIN. ONCE THE RAIN ENDS TONIGHT...LIGHT WINDS
WILL FOLLOW AND THERE IS POTENTIAL FOR FOG TO DEVELOP IN THE EARLY
MORNING HOURS. DMD

&&

.PREV DISCUSSION... /ISSUED 338 AM CDT SUN AUG 26 2012/

SYNOPSIS...
WEAK UPPER LEVEL WESTERLY FLOW CONTINUES OVER NEARLY ALL OF THE
CONUS. CORRESPONDINGLY WEAK 500MB TROUGH SPANS THE PLAINS FROM
SOUTHERN MINNESOTA INTO WEST TEXAS. PLUME OF LOW LEVEL MOISTURE IS
FEEDING FROM THE GULF OF MEXICO INTO THE UPPER MIDWEST...WITH 850MB
DEW POINTS AT OR ABOVE 15C OVER A SIGNIFICANT PORTION OF THE
SOUTHERN PLAINS AND LOWER MS VALLEY. AT THE SURFACE...LOW PRESSURE
IS CENTERED OVER KANSAS CITY THIS MORNING WITH A TROUGH EXTENDING TO
ITS SOUTHWEST...AND THE BEGINNINGS OF A WEAK WARM FRONT DEVELOPING
ACROSS NORTHERN MISSOURI AND SOUTHERN ILLINOIS.

SHORT TERM...TODAY AND TONIGHT...
FIRST WAVE OF SHOWERS ONGOING THIS MORNING OVER NORTHERN PORTIONS OF
THE CWFA...IN A BROAD AREA OF MID LEVEL ISENTROPIC LIFT AROUND
305K.  MAIN SHOW DRIVEN BY THE UPPER TROUGH IS NOW KNOCKING ON OUR
DOOR OVER SOUTHCENTRAL IOWA.  PRECIPITABLE WATERS ABOVE 2
INCHES...ABOUT 175 PERCENT OF NORMAL...OVER THE ENTIRE CWFA THIS
MORNING SUGGEST HIGHLY EFFICIENT RAINFALL PROCESSES. GIVEN THE WEAK
UPPER FLOW...SYSTEM WILL BE SLOW TO PROGRESS...FURTHER PADDING THE
RAINFALL TOTALS.  ALTHOUGH ONSET IS A BIT SLOWER THAN PREVIOUSLY
FORECAST...STILL LOOKS LIKE WE SHOULD SEE WIDESPREAD AMOUNTS NEAR
ONE INCH.  MID LEVEL LAPSE RATES SUGGEST POTENTIAL FOR WIDESPREAD
THUNDER IS LOW.  HOWEVER...ISOLATED EMBEDDED THUNDER HAS CONTINUED
OVERNIGHT OVER NORTHERN MISSOURI AND WILL MAINTAIN MENTION OF
ISOLATED THUNDER AS THE UPPER FORCING MOVES INTO THE AREA THIS
MORNING.

FAVORED THE RAP AND NAM TODAY AS BOTH HAVE A DECENT HANDLE ON THE
SURFACE FEATURES.  BASED ON THE NAM SOLUTION...BROAD SCALE LIFT
CONTINUES THROUGH MOST OF THE DAY AHEAD OF THE SURFACE LOW.  SHOULD
SEE PRECIP ENDING FROM WEST TO EAST LATE TODAY AND INTO TONIGHT AS
THE SYSTEM CLEARS THE AREA.

DMD

LONG TERM...MONDAY THROUGH NEXT SATURDAY...
MAINLY DRY WITH NEAR TO ABOVE NORMAL TEMPS AS SFC AND UPPER RIDGING
DOMINATES FOR MUCH OF THE PERIOD.

MON-WED... DRY AND FEW DEGS COOLER WITH LIGHT NORTHERLY WINDS TO
PERSIST FOR MUCH OF THE PERIOD VEERING TO EASTERLY BY WED AS SFC
HIGH SHIFTS THROUGH GREAT LAKES. H85 THERMAL GRADIENT W-E SHOWN
TO RESIDE OVER CWA WITH H85 TEMPS MAINLY IN RANGE OF 14-18C. THESE
VALUES MIXED TO SFC CLOSER TO DRY ADIABATICALLY SUPPORT WIDESPREAD
80S WITH COOLEST READINGS E/NE AND WARMEST S/SW. LOWS NEAR TO
BELOW COOLEST GUIDANCE WITH GOOD RADIATIONAL COOLING SETUP DURING
THE NIGHTS... WITH 50S FOR LOWS FAIRLY COMMON BOTH TUE AND WED AM.
DRY AIR SHOULD PROMOTE LARGE DIURNAL RANGES ON ORDER OF 30-35+ DEGS.

THU-SAT... UPPER LEVEL RIDGE BUILDS INTO REGION BY LATE WEEK AND THEN
FLATTENS. TEMPS ALOFT WARM WITH H85 TEMPS IN THE RANGE OF 20-25C.
BUT MODELS INDICATE WEAK MIXING REGIME WITH SFC RIDGE AXIS IN CLOSE
PROXIMITY... THUS NOT ABLE TO TAP FULL WARMTH AND SPARING US FROM
BAKING. THEREFORE... CONTINUATION OF MAINLY 80S FOR HIGHS. PCPN CHCS
LATE IN EXTENDED DEPENDENT ON MOVEMENT OF ISAAC REMNANTS.
OVERALL... HAVE SERIOUS DOUBTS THAT WE WILL SEE ANY IMPACT FROM
ISAAC DESPITE LATEST GFS AND GEM SOLUTIONS BRINGING REMNANTS
EITHER UP OVER CWA OR JUST GLANCING S/E CWA. TYPICALLY NEED LANDFALL
TO OCCUR IN TX OR WRN LA FOR THESE SYSTEMS TO HAVE ANY IMPACT
FOR OUR CWA. AT 06Z... GFS AND GEM WERE AROUND 3 MB TOO WEAK WITH
ISAAC AND THIS COULD AT LEAST PARTIALLY EXPLAIN THEIR MORE WESTERN
TRACK. IF WE SEE CONTINUED STRENGTHENING TDY TO HURRICANE THEN WOULD
EXPECT ISAAC TO START CURVING... AND IT WOULD SEEM VERY LIKELY THAT
ISAAC WOULD CONNECT WITH EASTERN TROUGH AND GET PULLED NORTHWARD.
THE KEY WILL BE AMOUNT/RATE OF INTENSIFICATION AS THE SLOWER ISAAC
TAKES TO RAMP UP THE MORE AND MORE A WESTERN TRACK WOULD BE POSSIBLE.
HAVE FOLLOWED HPC GUIDANCE CLOSELY LATE IN THE EXTENDED AND WILL HAVE
MAINLY DRY FCST FRI-SAT WITH ISAAC REMNANTS STAYING TO OUR E/SE.

MCCLURE

&&

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

$$

DMD/05/DMD






AREA FORECAST DISCUSSION

NWS GOODLAND KS

 922 AM MDT SUN AUG 26 2012

.UPDATE...
ISSUED AT 919 AM MDT SUN AUG 26 2012

JUST COMPLETED AN UPDATE. MAIN REASON FOR THE EXPIRATION OF THE
DENSE FOG ADVISORY/ENDING OF FOG. THEN ADJUSTED SKY COVER AND
DEWPOINTS BASED ON LATEST DATA AND TRENDS. ALSO UPDATED WINDS
THROUGH TOMORROW BASED ON LATEST TRENDS AND NAM DOING VERY WELL AT
THIS TIME. TODAYS LOOK CLOSE/IN GOOD SHAPE AND DID NOT MAKE ANY
ADJUSTMENTS. PRECIPITATION FORECAST FOR LATER THIS AFTERNOON AND
THIS EVENING ALSO LOOKS FINE.

UPDATE ISSUED AT 540 AM MDT SUN AUG 26 2012

UPDATE SENT TO INCLUDE GRAHAM...NORTON AND DECATUR COUNTIES TO THE
DENSE FOG ADVISORY.

UPDATE ISSUED AT 500 AM MDT SUN AUG 26 2012

HAVE ISSUED A DENSE FOG ADVISORY FOR HITCHCOCK AND RED WILLOW
COUNTIES THROUGH 9 AM MDT (10 AM CDT). VISIBILITIES AT KMCK 1/4
MILE OR LESS. LATEST RUC HAS A GOOD HANDLE ON THIS AND WITH LIGHT
WINDS EXPECT THE FOG TO DRIFT INTO HITCHCOCK COUNTY WITHIN THE
NEXT FEW HOURS. WILL HAVE TO WATCH THE ATWOOD AND OBERLIN AREAS
FOR POSSIBLE HEADLINE GIVEN SIMILAR CONDITIONS. WILL WAIT FOR CO-
OP REPORTS AND DAYLIGHT TO VIEW WEB CAMS BEFORE MAKING AND FURTHER
ADJUSTMENTS.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 215 AM MDT SUN AUG 26 2012

TODAY-TONIGHT...AT 08Z THIS MORNING STRATUS AND FOG WERE JUST
EAST OF THE FORECAST AREA BUT MOVING TOWARD THE WEST AT 15 MPH.
THIS WOULD PUT IT AS FAR WEST AS MCCOOK TO OBERLIN AND WAKEENEY BY
12Z THIS MORNING. VISIBILITIES ARE IN THE 1/4 MILE RANGE ARE
COMMON PER OBSERVATIONS. WILL CONTINUE TO WATCH JUST HOW FAR WEST
IT GETS AND SHOULD IT REACH THE FORECAST AREA A DENSE FOG ADVISORY
WILL BE NEEDED.

OTHERWISE OTHER CONCERN IS ON TIMING OF A FEW THUNDERSTORMS WHICH
SHOULD REACH THE WESTERN 1/4 OF THE AREA (MAINLY FAR EASTERN
COLORADO) BY LATE IN THE AFTERNOON. THESE APPEAR TO BE DIURNALLY
DRIVEN WITHIN AN AXIS OF 700-300 MOISTURE AND AM THINKING THAT ANY
STORMS THAT DO DEVELOP WILL DISSIPATE SHORTLY AFTER SUNSET. HIGH
TEMPERATURES TODAY UPPER 80S TO LOW 90S. LOWS TONIGHT UPPER 50S TO
LOW 60S.

MONDAY-TUESDAY NIGHT...UPPER RIDGE TO BUILD OVER COLORADO THROUGH
THE PERIOD. BREEZY SOUTH TO SOUTHEAST WINDS EXPECTED DURING THE
DAY WITH HIGH TEMPERATURES IN THE LOW TO MID 90S BOTH DAYS. LOWS
UPPER 50S TO LOW 60S.

.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 215 AM MDT SUN AUG 26 2012

THE H5 RIDGE THAT WILL DEVELOP EARLIER IN THE PERIOD IS EXPECTED
TO PERSIST UNTIL NEAR THE MIDDLE OF THE EXTENDED RANGE PERIOD WHEN
A WEAK FRONTAL ZONE MAY AFFECT THE TRI-STATE REGION. CONDITIONS
WILL BE HOT AND DRY WEDNESDAY AND THURSDAY AS THE H5 RIDGE
GRADUALLY MOVES EAST AS A TROUGH ENTERS THE PACIFIC NORTHWEST.
LATE THURSDAY A FRONTAL BOUNDARY BEGINS TO FORM THROUGH THE UPPER
HIGH PLAINS AND MOVE EAST DURING THE WEEKEND. FROM LOOKING AT THE
PAST FEW DAYS OF MODEL RUNS THIS FEATURE HAS CONSISTENT...BUT ITS
SPATIAL...TEMPORAL ...AND STRENGTH QUALITIES HAVE BEEN ALL OVER
THE MAP. THIS IS LIKELY DUE TO BOTH THE MODEL HANDLING OF THE
TROUGH DIGGING IN TO THE PACIFIC NORTHWEST AND TROPICAL STORM
ISAAC. FOR NOW HAVE INCLUDED MINIMAL SLIGHT CHANCE POPS ON FRIDAY
EVENING FOR THE NORTHWESTERN PART OF THE CWA...WITH DRY CONDITIONS
FORECAST FOR THE REST OF THE PERIOD. TEMPERATURES OVER THE PERIOD
WILL BE WARMER THAN AVERAGE...WITH HIGHS IN THE MID TO LOWER 90S.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 503 AM MDT SUN AUG 26 2012

DENSE FOG OF 1/4SM VISIBILITY WILL PERSIST THROUGH THE FIRST FEW
HOURS OF THE TAF AS PART OF A LARGE AREA OF DENSE FOG IN SOUTHERN
NEBRASKA AND NORTH CENTRAL KANSAS...WITH IFR CONDITIONS LASTING
UNTIL ABOUT 15Z. FOLLOWING THIS CONDITIONS WILL RAPIDLY IMPROVE TO
IFR CONDITIONS THROUGH THE REST OF THE PERIOD WITH CLEAR SKIES AND
A LIGHT SOUTH-SOUTHEAST WIND.

FOR GLD SOME PATCHY FOG IS EXPECTED THIS MORNING BUT IFR
CONDITIONS ARE NOT EXPECTED TO DEVELOP. ANY FOG THAT DOES DEVELOP WILL
QUICKLY DISSIPATE BY 14Z...AND CONDITIONS WILL REMAIN VFR FOR THE
REST OF THE PERIOD. CLEAR SKIES AND SOUTH-SOUTHEAST WINDS GUSTING
TO 20KTS WILL BE PREVAILING THIS AFTERNOON...WITH WEAKER WINDS
DURING THE OVERNIGHT HOURS.


&&

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

$$

UPDATE...BULLER
SHORT TERM...99
LONG TERM...JJM
AVIATION...99/JJM







AREA FORECAST DISCUSSION

NWS GOODLAND KS

 542 AM MDT SUN AUG 26 2012

.UPDATE...
ISSUED AT 540 AM MDT SUN AUG 26 2012

UPDATE SENT TO INCLUDE GRAHAM...NORTON AND DECATUR COUNTIES TO THE
DENSE FOG ADVISORY.

UPDATE ISSUED AT 500 AM MDT SUN AUG 26 2012

HAVE ISSUED A DENSE FOG ADVISORY FOR HITCHCOCK AND RED WILLOW
COUNTIES THROUGH 9 AM MDT (10 AM CDT). VISIBILITIES AT KMCK 1/4
MILE OR LESS. LATEST RUC HAS A GOOD HANDLE ON THIS AND WITH LIGHT
WINDS EXPECT THE FOG TO DRIFT INTO HITCHCOCK COUNTY WITHIN THE
NEXT FEW HOURS. WILL HAVE TO WATCH THE ATWOOD AND OBERLIN AREAS
FOR POSSIBLE HEADLINE GIVEN SIMILAR CONDITIONS. WILL WAIT FOR CO-
OP REPORTS AND DAYLIGHT TO VIEW WEB CAMS BEFORE MAKING AND FURTHER
ADJUSTMENTS.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 215 AM MDT SUN AUG 26 2012

TODAY-TONIGHT...AT 08Z THIS MORNING STRATUS AND FOG WERE JUST
EAST OF THE FORECAST AREA BUT MOVING TOWARD THE WEST AT 15 MPH.
THIS WOULD PUT IT AS FAR WEST AS MCCOOK TO OBERLIN AND WAKEENEY BY
12Z THIS MORNING. VISIBILITIES ARE IN THE 1/4 MILE RANGE ARE
COMMON PER OBSERVATIONS. WILL CONTINUE TO WATCH JUST HOW FAR WEST
IT GETS AND SHOULD IT REACH THE FORECAST AREA A DENSE FOG ADVISORY
WILL BE NEEDED.

OTHERWISE OTHER CONCERN IS ON TIMING OF A FEW THUNDERSTORMS WHICH
SHOULD REACH THE WESTERN 1/4 OF THE AREA (MAINLY FAR EASTERN
COLORADO) BY LATE IN THE AFTERNOON. THESE APPEAR TO BE DIURNALLY
DRIVEN WITHIN AN AXIS OF 700-300 MOISTURE AND AM THINKING THAT ANY
STORMS THAT DO DEVELOP WILL DISSIPATE SHORTLY AFTER SUNSET. HIGH
TEMPERATURES TODAY UPPER 80S TO LOW 90S. LOWS TONIGHT UPPER 50S TO
LOW 60S.

MONDAY-TUESDAY NIGHT...UPPER RIDGE TO BUILD OVER COLORADO THROUGH
THE PERIOD. BREEZY SOUTH TO SOUTHEAST WINDS EXPECTED DURING THE
DAY WITH HIGH TEMPERATURES IN THE LOW TO MID 90S BOTH DAYS. LOWS
UPPER 50S TO LOW 60S.

.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 215 AM MDT SUN AUG 26 2012

THE H5 RIDGE THAT WILL DEVELOP EARLIER IN THE PERIOD IS EXPECTED
TO PERSIST UNTIL NEAR THE MIDDLE OF THE EXTENDED RANGE PERIOD WHEN
A WEAK FRONTAL ZONE MAY AFFECT THE TRI-STATE REGION. CONDITIONS
WILL BE HOT AND DRY WEDNESDAY AND THURSDAY AS THE H5 RIDGE
GRADUALLY MOVES EAST AS A TROUGH ENTERS THE PACIFIC NORTHWEST.
LATE THURSDAY A FRONTAL BOUNDARY BEGINS TO FORM THROUGH THE UPPER
HIGH PLAINS AND MOVE EAST DURING THE WEEKEND. FROM LOOKING AT THE
PAST FEW DAYS OF MODEL RUNS THIS FEATURE HAS CONSISTENT...BUT ITS
SPATIAL...TEMPORAL ...AND STRENGTH QUALITIES HAVE BEEN ALL OVER
THE MAP. THIS IS LIKELY DUE TO BOTH THE MODEL HANDLING OF THE
TROUGH DIGGING IN TO THE PACIFIC NORTHWEST AND TROPICAL STORM
ISAAC. FOR NOW HAVE INCLUDED MINIMAL SLIGHT CHANCE POPS ON FRIDAY
EVENING FOR THE NORTHWESTERN PART OF THE CWA...WITH DRY CONDITIONS
FORECAST FOR THE REST OF THE PERIOD. TEMPERATURES OVER THE PERIOD
WILL BE WARMER THAN AVERAGE...WITH HIGHS IN THE MID TO LOWER 90S.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 503 AM MDT SUN AUG 26 2012

DENSE FOG OF 1/4SM VISIBILITY WILL PERSIST THROUGH THE FIRST FEW
HOURS OF THE TAF AS PART OF A LARGE AREA OF DENSE FOG IN SOUTHERN
NEBRASKA AND NORTH CENTRAL KANSAS...WITH IFR CONDITIONS LASTING
UNTIL ABOUT 15Z. FOLLOWING THIS CONDITIONS WILL RAPIDLY IMPROVE TO
IFR CONDITIONS THROUGH THE REST OF THE PERIOD WITH CLEAR SKIES AND
A LIGHT SOUTH-SOUTHEAST WIND.

FOR GLD SOME PATCHY FOG IS EXPECTED THIS MORNING BUT IFR
CONDITIONS ARE NOT EXPECTED TO DEVELOP. ANY FOG THAT DOES DEVELOP WILL
QUICKLY DISSIPATE BY 14Z...AND CONDITIONS WILL REMAIN VFR FOR THE
REST OF THE PERIOD. CLEAR SKIES AND SOUTH-SOUTHEAST WINDS GUSTING
TO 20KTS WILL BE PREVAILING THIS AFTERNOON...WITH WEAKER WINDS
DURING THE OVERNIGHT HOURS.


&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR KSZ003-004-
     016.

CO...NONE.
NE...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR NEZ080-081.

&&

$$

UPDATE...99
SHORT TERM...99
LONG TERM...JJM
AVIATION...99/JJM







AREA FORECAST DISCUSSION

NWS DODGE CITY KS

 614 AM CDT SUN AUG 26 2012

...UPDATE TO AVIATION...

.SYNOPSIS...
ISSUED AT 336 AM CDT SUN AUG 26 2012

ON THE SYNOPTIC SCALE...THE MID LEVEL TROUGH THAT BROUGHT ALL THE
RECENT RAINS EXTENDED FROM CENTRAL IOWA TO EASTERN KANSAS TO
NORTHWEST TEXAS EARLY THIS MORNING. SEVERAL THUNDERSTORM CLUSTERS
THRIVED THROUGH THE NIGHT ALONG THE TROUGH AXIS...PARTICULARLY FROM
NORTHERN OKLAHOMA INTO SOUTHEASTERN KANSAS. WATER VAPOR LOOP AS OF
08Z SHOWED SIGNIFICANT MID LEVEL DRYING IN THE WAKE OF THIS TROUGH
AXIS WITH SHORT WAVE RIDGING BUILDING IN ITS WAKE. ALSO IN ITS WAKE
IS A RATHER NON-EXISTENT MEAN SEA LEVEL PRESSURE FIELD WITH THE MSLP
ANALYSIS RATHER ISOBARIC IN NATURE AS MSLP WAS 1013 OR 1014MB FROM
WESTERN KANSAS INTO NEBRASKA, WESTERN IOWA, AND THE DAKOTAS. THIS
RESULTED IN WIDESPREAD CALM OR NEARLY CALM WINDS WITH RESIDUAL
MOISTURE REMNANT FROM BOTH THE RECENT RAINS AND INFLUX OF GULF OF
MEXICO MOISTURE INTO THE AREA AHEAD OF THE TROUGH WHICH WAS NOT
PUSHED OUT OF HERE WITH NO COLD FRONT.  A BAROCLINIC WAVE WHICH DID
PASS ACROSS THE SOUTHERN CANADIAN PRAIRIES DID PUSH A COLD FRONT
SOUTH YESTERDAY BUT STALLED OUT, WEAKENED, AND ULTIMATELY DIED OVER
THE SANDHILLS OF NEBRASKA.  AS OF 0815Z...THE 11-3.9 MICRON
SATELLITE LOOP CONFIRMED THE DEVELOPMENT OF LOW STRATUS AND FOG
ACROSS NORTH-CENTRAL KANSAS WHICH WAS PUSHING TOWARD THE HAYS AREA.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 336 AM CDT SUN AUG 26 2012

IN THE VERY SHORT TERM...LOW STRATUS AND FOG WILL BE THE MAIN ISSUE
ON THE AVIATION SIDE OF THINGS.  THE GRIDS ALREADY REFLECT
DEVELOPMENT OF CLOUDS AND PATCHY FOG...BUT WILL TRIM BACK THE
WESTERN EDGE OF THIS (ROUGHLY DIGHTON TO DODGE CITY TO COLDWATER
LINE) PER GUIDANCE FROM THE LATEST RUNS OF THE HRRR MODEL AS WELL AS
TRENDS ON SATELLITE.  THE FOG AND STRATUS PROBABLY WONT EVEN MAKE IT
THAT FAR WEST.  THE REST OF THE FORECAST FOR TODAY AND TONIGHT IS
FAIRLY STRAIGHT FORWARD UNDER THE MID LEVEL RIDGE AXIS.  HIGHS TODAY
WILL BE UPPER 80S TO NEAR 90 AS DIRECT INSOLATION WILL PREVAIL.
SURFACE WINDS WILL BEGIN TO RESPOND TO LOWERING PRESSURE OUT WEST
OVER THE HIGHER TERRAIN...BUT MAINLY ACROSS THE WESTERN COUNTIES
CLOSE TO THE COLORADO BORDER (WEST OF HIGHWAY 83). TONIGHT...ANOTHER
CLEAR AND (NEAR) CALM NIGHT IS EXPECTED WITH LOWS IN THE LOWER TO
MID 60S.  A PATCHY AREA OF LIGHT FOG WILL PROBABLY DEVELOP AGAIN IN
LOW LYING AREAS GIVEN IDEAL RADIATIONAL COOLING AND MOIST
GROUND...BUT THE COVERAGE OF ANY FOG DOES NOT REALLY WARRANT
INCLUSION IN GRIDS AT THIS TIME.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 123 AM CDT SUN AUG 26 2012

A RELATIVELY DRY PERIOD IS EXPECTED ACROSS WESTERN KANSAS AS MEDIUM
RANGE MODELS CONTINUE TO INDICATE A LARGE UPPER LEVEL RIDGE OF HIGH
PRESSURE PREVAILING ACROSS THE COLORADO ROCKIES AND THE WESTERN HIGH
PLAINS THROUGH AT LEAST MID WEEK. A GRADUAL WARMING TREND IS LIKELY
THROUGH AT LEAST WEDNESDAY AS A LEE SIDE TROUGH OF LOW PRESSURE
HELPS INFLUENCE A LOW LEVEL SOUTHERLY FLOW ACROSS WESTERN KANSAS
THROUGH MUCH OF THE PERIOD. FOR MONDAY, THE NAM, GFS, AND ECMWF SHOW
H85 TEMPERATURES RANGING FROM JUST ABOVE 20C ACROSS CENTRAL KANSAS
TO JUST ABOVE 25C NEAR THE COLORADO BORDER. ALONG WITH PLENTY OF
SUNSHINE, LOOK FOR HIGHS NEAR TO JUST ABOVE 90F MONDAY AFTERNOON.
THE WARMING TREND WILL CONTINUE WITH HIGHS EXPECTED UP INTO THE LOW
TO MID 90S(F) THROUGH AT LEAST THURSDAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 610 AM CDT SUN AUG 26 2012

LOW LEVEL STRATUS AND AREAS OF PATCHY FOG ACROSS CENTRAL KANSAS
WILL CONTINUE TO DRIFT WESTWARD THROUGH MID MORNING...MAINLY
AFFECTING KHYS WITH MVFR CIGS/VSBYS. A BRIEF PERIOD OF IFR CIGS
CANNOT BE RULED OUT AT KHYS BEFORE VFR CONDITIONS RETURN LATE THIS
MORNING. MVFR VSBYS ARE LIKELY TO CONTINUE AT KDDC AND KGCK
THROUGH AT LEAST 14Z WITH VFR CONDITIONS RAPIDLY RETURNING
SHORTLY THEREAFTER. VFR CONDITIONS WILL THEN PREVAIL AT ALL TAF
SITES THE REMAINDER OF THE DAY AND EVENING. AS FOR WINDS, SURFACE
HIGH PRESSURE IN THE NORTHERN PLAINS WILL SINK SOUTHWARD INTO
KANSAS TODAY. THIS WILL RESULT IN LIGHT AND VARIABLE WINDS THROUGH
MUCH OF THE DAY AND EVENING.

&&

.PRELIMINARY POINT TEMPS/POPS...
DDC  88  64  91  62 /   0  10   0   0
GCK  90  61  92  61 /   0  10   0   0
EHA  90  63  92  61 /   0  10   0   0
LBL  88  64  92  62 /   0  10   0   0
HYS  88  63  91  61 /   0  10   0   0
P28  87  67  92  64 /   0  10   0   0

&&

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

$$

SYNOPSIS...UMSCHEID
SHORT TERM...UMSCHEID
LONG TERM...JJOHNSON
AVIATION...JJOHNSON







AREA FORECAST DISCUSSION

NWS GOODLAND KS

 509 AM MDT SUN AUG 26 2012

.UPDATE...
ISSUED AT 500 AM MDT SUN AUG 26 2012

HAVE ISSUED A DENSE FOG ADVISORY FOR HITCHCOCK AND RED WILLOW
COUNTIES THROUGH 9 AM MDT (10 AM CDT). VISIBILITIES AT KMCK 1/4
MILE OR LESS. LATEST RUC HAS A GOOD HANDLE ON THIS AND WITH LIGHT
WINDS EXPECT THE FOG TO DRIFT INTO HITCHCOCK COUNTY WITHIN THE
NEXT FEW HOURS. WILL HAVE TO WATCH THE ATWOOD AND OBERLIN AREAS
FOR POSSIBLE HEADLINE GIVEN SIMILAR CONDITIONS. WILL WAIT FOR CO-
OP REPORTS AND DAYLIGHT TO VIEW WEB CAMS BEFORE MAKING AND FURTHER
ADJUSTMENTS.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 215 AM MDT SUN AUG 26 2012

TODAY-TONIGHT...AT 08Z THIS MORNING STRATUS AND FOG WERE JUST
EAST OF THE FORECAST AREA BUT MOVING TOWARD THE WEST AT 15 MPH.
THIS WOULD PUT IT AS FAR WEST AS MCCOOK TO OBERLIN AND WAKEENEY BY
12Z THIS MORNING. VISIBILITIES ARE IN THE 1/4 MILE RANGE ARE
COMMON PER OBSERVATIONS. WILL CONTINUE TO WATCH JUST HOW FAR WEST
IT GETS AND SHOULD IT REACH THE FORECAST AREA A DENSE FOG ADVISORY
WILL BE NEEDED.

OTHERWISE OTHER CONCERN IS ON TIMING OF A FEW THUNDERSTORMS WHICH
SHOULD REACH THE WESTERN 1/4 OF THE AREA (MAINLY FAR EASTERN
COLORADO) BY LATE IN THE AFTERNOON. THESE APPEAR TO BE DIURNALLY
DRIVEN WITHIN AN AXIS OF 700-300 MOISTURE AND AM THINKING THAT ANY
STORMS THAT DO DEVELOP WILL DISSIPATE SHORTLY AFTER SUNSET. HIGH
TEMPERATURES TODAY UPPER 80S TO LOW 90S. LOWS TONIGHT UPPER 50S TO
LOW 60S.

MONDAY-TUESDAY NIGHT...UPPER RIDGE TO BUILD OVER COLORADO THROUGH
THE PERIOD. BREEZY SOUTH TO SOUTHEAST WINDS EXPECTED DURING THE
DAY WITH HIGH TEMPERATURES IN THE LOW TO MID 90S BOTH DAYS. LOWS
UPPER 50S TO LOW 60S.

.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 215 AM MDT SUN AUG 26 2012

THE H5 RIDGE THAT WILL DEVELOP EARLIER IN THE PERIOD IS EXPECTED
TO PERSIST UNTIL NEAR THE MIDDLE OF THE EXTENDED RANGE PERIOD WHEN
A WEAK FRONTAL ZONE MAY AFFECT THE TRI-STATE REGION. CONDITIONS
WILL BE HOT AND DRY WEDNESDAY AND THURSDAY AS THE H5 RIDGE
GRADUALLY MOVES EAST AS A TROUGH ENTERS THE PACIFIC NORTHWEST.
LATE THURSDAY A FRONTAL BOUNDARY BEGINS TO FORM THROUGH THE UPPER
HIGH PLAINS AND MOVE EAST DURING THE WEEKEND. FROM LOOKING AT THE
PAST FEW DAYS OF MODEL RUNS THIS FEATURE HAS CONSISTENT...BUT ITS
SPATIAL...TEMPORAL ...AND STRENGTH QUALITIES HAVE BEEN ALL OVER
THE MAP. THIS IS LIKELY DUE TO BOTH THE MODEL HANDLING OF THE
TROUGH DIGGING IN TO THE PACIFIC NORTHWEST AND TROPICAL STORM
ISAAC. FOR NOW HAVE INCLUDED MINIMAL SLIGHT CHANCE POPS ON FRIDAY
EVENING FOR THE NORTHWESTERN PART OF THE CWA...WITH DRY CONDITIONS
FORECAST FOR THE REST OF THE PERIOD. TEMPERATURES OVER THE PERIOD
WILL BE WARMER THAN AVERAGE...WITH HIGHS IN THE MID TO LOWER 90S.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 503 AM MDT SUN AUG 26 2012

DENSE FOG OF 1/4SM VISIBILITY WILL PERSIST THROUGH THE FIRST FEW
HOURS OF THE TAF AS PART OF A LARGE AREA OF DENSE FOG IN SOUTHERN
NEBRASKA AND NORTH CENTRAL KANSAS...WITH IFR CONDITIONS LASTING
UNTIL ABOUT 15Z. FOLLOWING THIS CONDITIONS WILL RAPIDLY IMPROVE TO
IFR CONDITIONS THROUGH THE REST OF THE PERIOD WITH CLEAR SKIES AND
A LIGHT SOUTH-SOUTHEAST WIND.

FOR GLD SOME PATCHY FOG IS EXPECTED THIS MORNING BUT IFR
CONDITIONS ARE NOT EXPECTED TO DEVELOP. ANY FOG THAT DOES DEVELOP WILL
QUICKLY DISSIPATE BY 14Z...AND CONDITIONS WILL REMAIN VFR FOR THE
REST OF THE PERIOD. CLEAR SKIES AND SOUTH-SOUTHEAST WINDS GUSTING
TO 20KTS WILL BE PREVAILING THIS AFTERNOON...WITH WEAKER WINDS
DURING THE OVERNIGHT HOURS.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR NEZ080-081.

&&

$$

UPDATE...99
SHORT TERM...99
LONG TERM...JJM
AVIATION...99/JJM







AREA FORECAST DISCUSSION

NWS GOODLAND KS

 503 AM MDT SUN AUG 26 2012

.UPDATE...
ISSUED AT 500 AM MDT SUN AUG 26 2012

HAVE ISSUED A DENSE FOG ADVISORY FOR HITCHCOCK AND RED WILLOW
COUNTIES THROUGH 9 AM MDT (10 AM CDT). VISIBILITIES AT KMCK 1/4
MILE OR LESS. LATEST RUC HAS A GOOD HANDLE ON THIS AND WITH LIGHT
WINDS EXPECT THE FOG TO DRIFT INTO HITCHCOCK COUNTY WITHIN THE
NEXT FEW HOURS. WILL HAVE TO WATCH THE ATWOOD AND OBERLIN AREAS
FOR POSSIBLE HEADLINE GIVEN SIMILAR CONDITIONS. WILL WAIT FOR CO-
OP REPORTS AND DAYLIGHT TO VIEW WEB CAMS BEFORE MAKING AND FURTHER
ADJUSTMENTS.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 215 AM MDT SUN AUG 26 2012

TODAY-TONIGHT...AT 08Z THIS MORNING STRATUS AND FOG WERE JUST
EAST OF THE FORECAST AREA BUT MOVING TOWARD THE WEST AT 15 MPH.
THIS WOULD PUT IT AS FAR WEST AS MCCOOK TO OBERLIN AND WAKEENEY BY
12Z THIS MORNING. VISIBILITIES ARE IN THE 1/4 MILE RANGE ARE
COMMON PER OBSERVATIONS. WILL CONTINUE TO WATCH JUST HOW FAR WEST
IT GETS AND SHOULD IT REACH THE FORECAST AREA A DENSE FOG ADVISORY
WILL BE NEEDED.

OTHERWISE OTHER CONCERN IS ON TIMING OF A FEW THUNDERSTORMS WHICH
SHOULD REACH THE WESTERN 1/4 OF THE AREA (MAINLY FAR EASTERN
COLORADO) BY LATE IN THE AFTERNOON. THESE APPEAR TO BE DIURNALLY
DRIVEN WITHIN AN AXIS OF 700-300 MOISTURE AND AM THINKING THAT ANY
STORMS THAT DO DEVELOP WILL DISSIPATE SHORTLY AFTER SUNSET. HIGH
TEMPERATURES TODAY UPPER 80S TO LOW 90S. LOWS TONIGHT UPPER 50S TO
LOW 60S.

MONDAY-TUESDAY NIGHT...UPPER RIDGE TO BUILD OVER COLORADO THROUGH
THE PERIOD. BREEZY SOUTH TO SOUTHEAST WINDS EXPECTED DURING THE
DAY WITH HIGH TEMPERATURES IN THE LOW TO MID 90S BOTH DAYS. LOWS
UPPER 50S TO LOW 60S.

.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 215 AM MDT SUN AUG 26 2012

THE H5 RIDGE THAT WILL DEVELOP EARLIER IN THE PERIOD IS EXPECTED
TO PERSIST UNTIL NEAR THE MIDDLE OF THE EXTENDED RANGE PERIOD WHEN
A WEAK FRONTAL ZONE MAY AFFECT THE TRI-STATE REGION. CONDITIONS
WILL BE HOT AND DRY WEDNESDAY AND THURSDAY AS THE H5 RIDGE
GRADUALLY MOVES EAST AS A TROUGH ENTERS THE PACIFIC NORTHWEST.
LATE THURSDAY A FRONTAL BOUNDARY BEGINS TO FORM THROUGH THE UPPER
HIGH PLAINS AND MOVE EAST DURING THE WEEKEND. FROM LOOKING AT THE
PAST FEW DAYS OF MODEL RUNS THIS FEATURE HAS CONSISTENT...BUT ITS
SPATIAL...TEMPORAL ...AND STRENGTH QUALITIES HAVE BEEN ALL OVER
THE MAP. THIS IS LIKELY DUE TO BOTH THE MODEL HANDLING OF THE
TROUGH DIGGING IN TO THE PACIFIC NORTHWEST AND TROPICAL STORM
ISAAC. FOR NOW HAVE INCLUDED MINIMAL SLIGHT CHANCE POPS ON FRIDAY
EVENING FOR THE NORTHWESTERN PART OF THE CWA...WITH DRY CONDITIONS
FORECAST FOR THE REST OF THE PERIOD. TEMPERATURES OVER THE PERIOD
WILL BE WARMER THAN AVERAGE...WITH HIGHS IN THE MID TO LOWER 90S.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1132 PM MDT SAT AUG 25 2012

VFR TO LIFR CONDITIONS ARE FORECAST FOR THE 6Z TAFS. LATEST REPORT
FROM KMCK HAS VISIBILITIES DROPPING TO 7 MILES WITH WINDS AROUND 5
KTS. WITH VIS DROPPING THIS QUICKLY DESPITE THE LIGHT BREEZE HAVE
SPED UP THE TIMING OF VISIBILITIES DROPPING. THE OVERALL TIMING
MAY BE OFF AN HOUR EITHER DIRECTION BUT GENERALLY AM THINKING
VISIBILITIES WILL BE LOWEST CLOSER TO 12Z. VISIBILITY COULD DROP AS
LOW AS A QUARTER MILE FOR A BRIEF TIME...BUT DO NOT HAVE ENOUGH
CONFIDENCE THE WIND WILL STAY LIGHT ENOUGH FOR LONG ENOUGH TO
WARRANT A MENTION IN THE TAF. AFTER 12Z THE FOG SHOULD QUICKLY
BURN OFF.

DID INCLUDE A BRIEF MVFR WINDOW FOR KGLD SINCE MOS GUIDANCE
INDICATES VISIBILITIES COULD DIP BELOW 6 MILES FOR A SHORT TIME.
OTHERWISE FOG WILL QUICKLY DISSIPATE AFTER 12Z.


&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR NEZ080-081.

&&

$$

UPDATE...99
SHORT TERM...99
LONG TERM...JJM
AVIATION...JTL







AREA FORECAST DISCUSSION

NWS PADUCAH KY

 859 AM CDT SUN AUG 26 2012

.UPDATE...
ISSUED AT 855 AM CDT SUN AUG 26 2012

JUST UPDATED THE KPAH TAF AND THE PUBLIC FORECAST TO ACCOUNT FOR
SCATTERED SHOWERS ONGOING OVER THE PURCHASE AREA EARLY THIS
MORNING. THE HRRR...06Z NAM AND 00Z WRF RUNS ALL INDICATE AN
UPTICK IN COVERAGE AS THIS ZONE OF SHOWERS PUSHES EASTWARD ACROSS
THE AREA THIS MORNING. TRIED TO INDICATE THIS IN THE POP GRIDS
THROUGH 18Z.

THEY ALSO INDICATE A TREND TOWARD DEVELOPMENT IN THE WEST LATER
THIS AFTERNOON...ESPECIALLY IF THAT AREA CAN WARM UP ANY. TRIED TO
USED THE HRRR AND NAM 2-M TEMPERATURE FORECASTS TO SHOW A
REALISTIC TEMPERATURE TREND THROUGH THE DAY. GIVEN THE AMOUNT OF
CLOUDS OVER THE AREA...AND A FEW CONSPICUOUSLY CLEAR
AREAS...TEMPERATURE TRENDS WILL BE A BEAR TO KEEP UP WITH TODAY.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 313 AM CDT SUN AUG 26 2012

BIGGEST FORECAST CHALLENGE WILL BE WITH RAIN/THUNDER CHANCES...
MAINLY TODAY....AND ESP MON. MID LEVEL TROF AND ASSOCIATED WEAK
SFC SHOULD EVENTUALLY MOVE EAST FROM THE PLAINS AND START TO BRING
SHOWER/THUNDER CHCS TO AREAS ALONG AND WEST OF THE MS RIVER
TODAY/TONIGHT. HOWEVER...IT STILL APPEARS THE BEST CHANCE OF A
MORE WIDESPREAD PRECIP COVERAGE WILL COME ON MONDAY AS THE SFC
FRONT DRIFTS SLOWLY THROUGH THE FORECAST AREA. NOT LOOKING AT A
MAJOR RAIN SYSTEM AT THIS TIME...AND EXTENSIVE CLOUDS SUN NIGHT/MON
WILL LIKELY PRECLUDE ANY SEVERE STORM RISK. RAIN CHANCES WILL
DIMINISH FROM WEST TO EAST MONDAY NIGHT AS THE SFC FRONT EASES
SOUTHEAST AND H70 TROF SHIFTS EAST. THIS SHOULD CREATE A RATHER
DRY TUESDAY. WILL STICK CLOSE TO ONGOING TEMPS....SLIGHTLY ABOVE
NORMAL FOR THIS TIME OF YEAR.

.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 340 AM CDT SAT AUG 25 2012

THE MAIN CONCERN CONTINUES TO BE THE PATH OF TS ISAAC.

THE LATEST MODELS RUNS CONTINUE TO BE IN COMPLETE DISARRAY. THE 12Z
SATURDAY  ECMWF FOR THE FIRST TIME TAKES THE EASTERN MOST PATH ALONG
THE EASTERN COAST. PREVIOUS 3 DAYS IT HAS RANGED FROM WESTERN MO TO
WESTERN KY SO THIS IS THE LARGEST FLIP FLOP FOR THE OPERATIONAL
ECMWF. THE LATEST 00Z SUN ECMWF ACTUALLY BRINGS THE CENTER OF THE
REMNANTS OF ISAAC OVER THE PENNYRILE AREA OF W KY. THE 00Z SUN GFS
RUN ACTUALLY BRINGS THE CENTER OF ISAAC OVER SGF. FOR THE FIRST TIME
THIS WEEK THE GFS HAS THE WESTERN TRACK AND THE ECMWF HAS THE
EASTERN TRACK. THE ENSEMBLES ARE MUCH HELP EITHER. MOST OF THE
MODELS PERFORM WELL UNTIL ISSAC MAKES LANDFALL AND THEN ITS A CRAP
SHOOT AS FAR AS THE MODELS GO. THIS UNCERTAINTY WILL WREAK HAVOC ON
TEMP FCST AS WELL. AS PREVIOUS DISC STATED IT COULD BE 70S WITH
ISSAC OVER THE AREA OR MID 90S IF IT MISSES US. SO AGAIN DRAMATIC
CHANGES SHOULD BE ANTICIPATED WITH THE EXTENDED SHOULD A REASONABLE
SOLUTION REVEAL ITSELF IN THE NEAR FUTURE. FOR NOW WILL LEAN TOWARD
THE NHC FCST AS DID HPC BUT CONFIDENCE IS EXTREMELY LOW.

FOR THE AFOREMENTIONED REASONS LITTLE CHANGE WAS MADE TO TEMPS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 313 AM CDT SUN AUG 26 2012

FOR THE MOST PART...VFR CEILINGS ARE EXPECTED TO SPREAD NORTH AND EAST
DURING THE PERIOD. SCT LIGHT RAIN SHOWERS MAY AFFECT A FEW TAF
SITES TONIGHT...BUT CONDITIONS SHOULD REMAIN MOSTLY ON THE VFR SIDE.
LIGHT SOUTH WINDS SHOULD STAY BELOW 10 KTS.


&&

.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&

$$

UPDATE...DRS
SHORT TERM...MEFFERT
LONG TERM....KH
AVIATION...MEFFERT







AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 741 AM EDT SUN AUG 26 2012

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 503 AM EDT SUN AUG 26 2012

SYNOPSIS...WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL
LOW NE OF LAKE WINNIPEG RESULTING IN SW FLOW FROM THE UPPER MS VALLEY
INTO THE NRN GREAT LAKES. AT THE SFC... A COLD FRONT EXTENDED FROM A
TRIPLE POINT WEST OR JAMES BAY SW TO NEAR CYQT/KDLH. -SHRA INTO
CNTRL UPPER MI WERE SUPPORTED BY A WEAK SHRTWV OVER NRN WI IN THE
MOISTURE PLUME REACHING FROM THE SRN PLAINS INTO UPPER MI AND NRN
ONTARIO. ADDITIONAL SHRA WERE ALSO MOVING NE INTO CNTRL WI.
A LINE OF TSRA HAD DEVELOPED AHEAD N OF LAKE SUPERIOR AHEAD OF THE
COLD FRONT ASSOCIATED WITH STRONGER QVECTOR CONV AND HEIGHT FALLS
AHEAD OF THE MID LEVEL TROUGH.

TODAY AND TONIGHT...EXPECT SCT SHRA TO CONTINUE INTO THE CNTRL AND EAST CWA
THIS MORNING...PER RADAR/SATELLITE TRENDS AS ANOTHER WEAK SHORTWAVE
LIFTS TOWARD THE AREA. EVEN THOUGH THICKER CLOUD COVER WILL HOLD TEMPS
DOWN COMPARED TO SATURDAY...EVEN MODEST WARMING AHEAD OF THE FRONT
SHOULD STILL PUSH MAX READINGS TO AROUND 80. WITH THE TEMP
RECOVERY...MUCAPE VALUES MAY ALSO CLIMB INTO THE 500-1000 J/KG RANGE
TO SUPPORT TSRA CHANCES BY LATE THIS MORNING INTO THIS EVENING AS THE
COLD FRONT EDGES THROUGH THE AREA. HOWEVER...SINCE LOW LEVEL CONV AND
FORCING WITH THE FRONT WILL BE RELATIVELY WEAK...THE FCST ONLY
INCLUDES LOWER END CHANCE POPS. ANY REMAINING SHRA/TSRA WILL EXIT THE
ERN CWA AFT 03Z.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 503 AM EDT SUN AUG 26 2012

OVERALL PATTERN FOR THE LONG TERM WILL FEATURE AN UPPER TROUGH
PUSHING INTO THE UPPER GREAT LKS ON SUN NIGHT AND MON BEFORE
SHIFTING E INTO THE NEW ENGLAND STATES. THIS WILL ALLOW AN UPPER
RIDGE TO BUILD OVER THE ROCKIES AND NORTHERN PLAINS WHILE SLOWLY
SHIFTING E INTO THE UPPER MISS VALLEY FOR WED AND THE UPPER GREAT
LKS ON THURS. AT THE SFC...NW FLOW WILL TAKE HOLD FOR MON AHEAD OF
HIGH PRESSURE SLIDING OUT OF THE CANADIAN PRAIRIES AND NORTHERN
PLAINS AND INTO THE UPPER MISS VALLEY. THIS HIGH WILL SLIDE SE OVER
THE UPPER GREAT LAKES REGION FOR MON NIGHT THROUGH WED AND THEN
SLIDE SOUTHEAST INTO THE LOWER GREAT LAKES ON WED NIGHT AND THURS.

MODELS CONSISTENT ON SHORTWAVE MOVING THROUGH ON MON AFTN UNDER THE
NW FLOW ALOFT. H700-500 MOISTURE IS VERY LIMITED...WITH THE BEST
AREA OVER LK SUPERIOR AND ALIGNED WITH STEEPENING LAPSE RATES TO 6.5
C/KM. LOWER MOISTURE IS ALSO LIMITED AND MODELS TRY TO DIMINISH IT
AS IT DROPS SE ACROSS THE CWA. WITH THE MOISTURE AROUND
H850...THINKING IT SHOULD BE ENOUGH FOR AT LEAST SOME DIURNAL CU.
BUT WITH LITTLE TO NO INSTABILITY DUE TO CAPPING INVERSION BETWEEN
H800-600...DON/T EXPECT MUCH MORE THAN THAT. THEREFORE...HAVE BUMPED
THE CLOUDS UP A LITTLE OVER NRN/ERN LK SUPERIOR WHERE THE BETTER MID
LVL MOISTURE IS LOCATED AND ALSO OVER THE LAND AREAS WITH THE
DIURNAL CU.

WITH THE HIGH MOVING IN MON NIGHT...SHOULD BE A DRY PERIOD FOR MUCH
OF THE WORK WEEK. DIURNAL CU POSSIBLE AGAIN ON TUES...BUT THIS TIME
CONFINED TO THE INTERIOR CENTRL AND NEAR LK MI AS THE DRIER AIR FROM
THE HIGH SETTLES IN. UPPER TROUGH SLIDING THROUGH WITH THE CANADIAN
HIGH WILL LEAD TO COOLER TEMPERATURES FOR MON/TUES...WITH HIGHS
MAINLY IN THE 70S. THEN AS THE HIGH SHIFTS SE...SWRLY RETURN FLOW
WILL START TO PUSH TEMPS BACK UP AND ON A BREEZY THURS...HIGHS WILL
APPROACH 90 DEGREES ONCE AGAIN UNDER THE UPPER RIDGE.

THEN FOR FRI/SAT...EXTENDED MODELS AND THEIR ENS MEANS CONSISTENT ON
THE IDEA OF THE UPPER RIDGE FLATTENING OUT DUE TO A SHORTWAVE
PULLING OUT OF THE UPPER TROUGH OVER THE PAC NW. STILL SOME
DIFFERENCES IN THE INTENSITY OF THE WAVE AND THE EXACT TRACK...BUT
THE TIMING OF MOVING FROM OREGON TO NRN ONTARIO ON THURS/FRI IS
CONSISTENT. THIS WOULD LEAD TO A WEAK COLD FRONT MOVING ACROSS THE
AREA ON THURS NIGHT AND FRI. RIGHT NOW...APPEARS TO BE FAIRLY
DRY...SO WILL ONLY MENTION SLIGHT CHANCES OVER THE NW HALF OF LK
SUPERIOR. THINGS REALLY START TO DIFFER ON SAT...AS 00Z GFS WANTS TO
PULL ANOTHER UPPER WAVE ACROSS SRN ONTARIO. 00Z GFS ENS MEAN DOESN/T
FOLLOW THIS IDEA AND STAYS CLOSER TO 12Z ECMWF DETERMINISTIC AND ENS
MEAN ON WRLY FLOW. THUS...WILL FOLLOW THAT IDEA AND KEEP MUCH OF THE
AREA DRY AND CONTINUE THE ABOVE NORMAL TEMPS WITH HIGHS IN THE UPPER
70S AND LOWER 80S.
&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 739 AM EDT SUN AUG 26 2012

A SLOW MOVING LOW PRES TROUGH WILL BRING THE THREAT OF SOME -SHRA
AND PERHAPS A TS W-E TO MAINLY CMX/SAW TODAY. THE QUICKER PASSAGE OF
THIS BOUNDARY THIS AFTN AND AN INFLUX OF DRIER AIR IN ITS WAKE WILL
END THE PCPN THREAT AT IWD/CMX EARLIER THAN AT SAW. TS CHANCES ARE
TOO LOW TO BE SPECIFIC FOR TIMING ATTM...BUT THE BEST SHOT FOR A TS
WOULD BE LATE TODAY AT SAW. ALTHOUGH MVFR CONDITIONS ARE POSSIBLE
IMMEDIATELY AHEAD OF THE COLD FROPA AT ALL 3 SITES AND UNDER ANY
HEAVIER SHRA...LACK OF SIGNIFICANT LOW LEVEL MOISTENING SUGGESTS VFR
CONDITIONS WILL PREVAIL.

&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 503 AM EDT SUN AUG 26 2012

WINDS ARE EXPECTED TO REMAIN BELOW 30KTS THROUGH THE FORECAST PERIOD.
LOW PRES OVER CENTRAL MANITOBA LOW PRESSURE WILL LIFT ACROSS HUDSON
BAY TODAY...AND NORTHERN QUEBEC ON MONDAY. THIS WILL KEEP A TROUGH
ACROSS LAKE SUPERIOR THROUGH SUNDAY NIGHT. HIGH PRESSURE STRETCHING
FROM MANITOBA THE CENTRAL PLAINS MONDAY MORNING WILL SLOWLY BUILD
ACROSS THE UPPER GREAT LAKES THROUGH TUESDAY...BEFORE SINKING TO THE
LOWER GREAT LAKES WEDNESDAY. A LOW WILL SLIDE FROM CENTRAL MANITOBA
TO CENTRAL ONTARIO AND HUDSON BAY BY THURSDAY EVENING...ALLOWING A
TROUGH TO DIP OVER LAKE SUPERIOR.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...JLB
LONG TERM...SRF
AVIATION...JLB
MARINE...JLB







AREA FORECAST DISCUSSION...UPDATED

NWS NORTH PLATTE NE

 708 AM CDT SUN AUG 26 2012

.AVIATION...
WIDESPREAD DENSE FOG OVER WESTERN AND NORTH CENTRAL NEBRASKA EAST
OF A KIML TO KANW LINE. KLBF ZERO VISIBILITY AND KBBW 1/4SM.
CEILINGS AND VISIBILITIES WILL IMPROVE THROUGH LATE MORNING. VFR
CONDITIONS THIS AFTERNOON. ISOLATED THUNDERSTORMS EXPECTED TO
DEVELOP IN THE NEBRASKA PANHANDLE LATE THIS AFTERNOON AND WILL
MOVE EAST INTO THE WESTERN NEBRASKA SANDHILLS THROUGH THE EARLY
EVENING BEFORE DISSIPATING. STRONG ERRATIC WINDS IN THE VICINITY
OF THUNDERSTORMS.

&&

.PREV DISCUSSION... /ISSUED 631 AM CDT SUN AUG 26 2012/

UPDATE...
UPDATED TO INCLUDE EXPANDING DENSE FOG CONDITIONS.

PREV DISCUSSION... /ISSUED 339 AM CDT SUN AUG 26 2012/

SHORT TERM...TODAY THROUGH WEDNESDAY

PRIMARY CONCERNS FOR THE FORECAST ARE THUNDERSTORM CHANCES THIS
AFTERNOON AND EVENING AND AGAIN MONDAY EVENING...AS WELL AS
TEMPERATURES. ALSO KEEPING AN EYE ON FIRE CONCERNS THROUGH THE
FIRST HALF OF THE WEEK.

WATER VAPOR IMAGERY THIS MORNING WAS SHOWING THE UPPER LEVEL
SHORTWAVE TROUGH WHICH PUSHED THE COLD FRONT ACROSS THE FORECAST
AREA ON SATURDAY LOCATED FROM CENTRAL KANSAS INTO WISCONSIN.
THE FRONT HAD STALLED OUT JUST TO THE EAST OF THE FORECAST AREA
AND HAD SINCE WASHED OUT...WITH HIGH PRESSURE NOW CENTERED OVER
WESTERN NEBRASKA. THE DEWPOINT GRADIENT REMAINS...WITH MOIST AIR
OVER EASTERN NEBRASKA /60 DEGREE DEWPOINTS ALONG AND EAST OF A KMCK
TO KBBW TO KONL LINE/...WITH VALUES IN THE 30S OVER THE NORTHERN
PANHANDLE. THUNDERSTORMS WERE ONGOING AHEAD OF THE SYSTEM...INTO
IOWA AND MISSOURI...WHILE STRATUS AND FOG WERE OBSERVED ACROSS
MUCH OF EASTERN NEBRASKA.

ONCE AGAIN LOOKING AT THE LARGE SCALE FLOW...THE UPPER LEVEL RIDGE
WAS CENTERED OVER THE SOUTHERN ROCKY MOUNTAIN RANGE. ALSO OF
NOTE...TROPICAL STORM ISAAC REMAINS A FOCAL POINT WITH THE CENTER
CURRENTLY MOVING OVER CUBA.

THE LOCAL FORECAST AREA IS RIGHT ON THE EDGE OF THE LOW LEVEL
MOISTURE AND FOG THIS MORNING. THE RAP SEEMS TO HAVE A GOOD HANDLE
ON THIS MOISTURE AND SHOWS IT DISSIPATING BY 16Z. WITH THE
PLACEMENT OF THE MOISTURE...AND THAT THE MODELS ARE PUSHING THE
SURFACE LOW INTO THE PANHANDLE TO TIGHTEN THE PRESSURE GRADIENT
AND INCREASE THE WIND...THIS SEEMS LIKE A GOOD SOLUTION AND WILL
FOLLOW THIS LEAD INTO THE FORECAST FOR TODAY. WITH THE EARLY
DISMISSAL OF THE CLOUDS...AND RETURN FLOW...WOULD EXPECT STRONG
WARMING TODAY. TEMPERATURES DO WARM A FEW DEGREES ALOFT FROM WHAT
WAS OBSERVED ON SATURDAY...ALTHOUGH SOUNDINGS ARE INDICATING FULL
MIXING WON/T BE REALIZED. HOWEVER WITH THE EXTRA HOURS OF
SUNSHINE...BELIEVE 90S ARE ATTAINABLE FOR TODAY IN MOST LOCATIONS.

AN UPPER LEVEL SHORTWAVE TROUGH WAS OBSERVED EARLY THIS MORNING
MOVING INTO WYOMING. THIS ENERGY WILL BE THE FOCUS FOR
THUNDERSTORM DEVELOPMENT LATER TODAY. ALTHOUGH THE RETURN FLOW
DOESN/T LOOK PARTICULARLY STRONG UNTIL LATER THIS EVENING...BOTH
THE NAM AND GFS INCREASE PRECIPITABLE WATER TO VALUES OF AN INCH
OR MORE /120 PERCENT OF NORMAL/ OVER THE PANHANDLE /JUST FOR
REFERENCE THE 26.00Z LBF SOUNDING OBSERVED PW OF 0.67...WHILE RAP
HAD 0.43/. EVEN IF THE MOISTURE DOESN/T INCREASE THIS MUCH...THERE
SHOULD BE ENOUGH TO ALLOW FOR ISOLATED THUNDERSTORMS TO DEVELOP
OVER THE PANHANDLE LATER THIS AFTERNOON. SOUNDINGS SHOWING
INVERTED-V PROFILE SO WILL CONTINUE TO SEE THE THREATS FOR STRONG
AND ERRATIC WINDS FROM ANY STORMS...AS WELL AS LOW RAINFALL
AMOUNTS AND A CHANCE FOR SOME STRAY DRY LIGHTNING STRIKES. GOING
EASTWARD...MOISTURE INCREASE ISN/T AS SUBSTANTIAL...AND WITH LARGE
SCALE FORCING BEING LESS...THESE AREAS WILL STAY CAPPED SO WILL
KEEP AREAS EAST OF A LINE FROM NORTH PLATTE TO AINSWORTH DRY.

MONDAY WILL BE A SIMILAR DAY TO SUNDAY...WITH STRONG WARMING
EXPECTED WITH LOTS OF SUNSHINE AND HIGHS IN THE 90S. ALTHOUGH THE
RIDGE WILL BUILD INTO THE PLAINS THROUGH THE DAY...A DECENT
SHORTWAVE TROUGH IS SIGNALED TO PUSH OVER THE RIDGE AND INTO
NEBRASKA IN THE AFTERNOON. THIS SIGNAL WAS BEING PICKED UP BY THE
ECMWF/NAM/GEM-REGIONAL/SREF...AND WITH THE PROPER PLACEMENT OF THE
RIDGE...FELT IT WAS FITTING TO ADD A SLIGHT CHANCE OVER TH
PANHANDLE AND FAR NORTHWEST NEBRASKA.

TUESDAY AND WEDNESDAY SHOULD BE DRY...WITH THE UPPER LEVEL RIDGE
IN PLACE OVER THE HIGH PLAINS AND LOW PRESSURE AT THE SURFACE OFF
TO THE WEST. WINDS WILL BE BREEZY FROM THE SOUTH BOTH
DAYS...HOWEVER ALL MODELS ARE IN AGREEMENT WITH KEEPING MOISTURE
LIMITED...WITH DEWPOINTS IN THE 40S AND 50S. THE LACK OF MOISTURE
ADVECTION LIKELY HAS SOMETHING TO DO WITH TROPICAL STORM ISAAC
/LIKELY HURRICANE ISAAC BY THIS TIME/ TAKING MUCH OF THE AVAILABLE
MOISTURE. TUESDAY LOOKS TO BE THE WARMEST DAY OF THE WEEK...WITH
MID TO UPPER 90S EXPECTED...WITH WIDESPREAD 90S FOR WEDNESDAY AS
WELL.

FIRE WEATHER CONCERNS WILL BE ON THE FOREFRONT MONDAY THROUGH
WEDNESDAY...WITH THE COMBINATION OF THE DRY AIR AND BREEZY WINDS.
ALTHOUGH THE CURRENT FORECAST WOULD KEEP CONDITIONS OUT OF
CRITICAL CRITERIA...THE EXTREME DRYNESS OF THE FUELS COULD CAUSE
THE NEED FOR RED FLAG WARNINGS IF CONDITIONS ARE EXPECTED TO BE
CLOSE.

LONG TERM...THURSDAY THROUGH SATURDAY

THE UPPER LEVEL RIDGE HOLDS STRONG THROUGH THE SECOND HALF OF THE
WEEK. THIS WILL KEEP TEMPERATURES WARM AND ABOVE NORMAL IN THE
90S...WITH LITTLE IF ANY CHANCES FOR RAIN. AS THE RIDGE SHIFTS
EAST...COULD GET PACIFIC MOISTURE TO PUSH INTO THE NORTHERN AND
CENTRAL PLAINS...HOWEVER MODELS ARE NOT INDICATING ANY UPPER LEVEL
SUPPORT FOR ANY SHOWER OR STORM DEVELOPMENT SO KEPT THE FORECAST
DRY. IN TURN...THE STRENGTH OF THE RIDGE WILL LIKELY KEEP ANY
MOISTURE FROM ISAAC WELL EAST OF THE PLAINS. THERE HAS BEEN
CONSIDERABLE DIFFERENCES IN WHERE THE SYSTEM WILL TRACK ONCE
COMING ON-SHORE BUT AGAIN BECAUSE OF THE RIDGE OVER THE
PLAINS...IT WILL PROBABLY MOVE NORTH INTO THE OHIO RIVER VALLEY OR
EVEN ALONG THE EAST COAST.


&&

.LBF WATCHES/WARNINGS/ADVISORIES...DENSE FOG ADVISORY UNTIL 10 AM CDT
THIS MORNING FOR NEZ007-009-010-026>029-037-038-059-070-071.

&&

$$

SHORT TERM/EXTENDED...POWER/BROOKS
AVIATION...POWER






AREA FORECAST DISCUSSION...UPDATED

NWS NORTH PLATTE NE

 631 AM CDT SUN AUG 26 2012

.UPDATE...
UPDATED TO INCLUDE EXPANDING DENSE FOG CONDITIONS.

&&

.PREV DISCUSSION... /ISSUED 339 AM CDT SUN AUG 26 2012/

SHORT TERM...TODAY THROUGH WEDNESDAY

PRIMARY CONCERNS FOR THE FORECAST ARE THUNDERSTORM CHANCES THIS
AFTERNOON AND EVENING AND AGAIN MONDAY EVENING...AS WELL AS
TEMPERATURES. ALSO KEEPING AN EYE ON FIRE CONCERNS THROUGH THE
FIRST HALF OF THE WEEK.

WATER VAPOR IMAGERY THIS MORNING WAS SHOWING THE UPPER LEVEL
SHORTWAVE TROUGH WHICH PUSHED THE COLD FRONT ACROSS THE FORECAST
AREA ON SATURDAY LOCATED FROM CENTRAL KANSAS INTO WISCONSIN.
THE FRONT HAD STALLED OUT JUST TO THE EAST OF THE FORECAST AREA
AND HAD SINCE WASHED OUT...WITH HIGH PRESSURE NOW CENTERED OVER
WESTERN NEBRASKA. THE DEWPOINT GRADIENT REMAINS...WITH MOIST AIR
OVER EASTERN NEBRASKA /60 DEGREE DEWPOINTS ALONG AND EAST OF A KMCK
TO KBBW TO KONL LINE/...WITH VALUES IN THE 30S OVER THE NORTHERN
PANHANDLE. THUNDERSTORMS WERE ONGOING AHEAD OF THE SYSTEM...INTO
IOWA AND MISSOURI...WHILE STRATUS AND FOG WERE OBSERVED ACROSS
MUCH OF EASTERN NEBRASKA.

ONCE AGAIN LOOKING AT THE LARGE SCALE FLOW...THE UPPER LEVEL RIDGE
WAS CENTERED OVER THE SOUTHERN ROCKY MOUNTAIN RANGE. ALSO OF
NOTE...TROPICAL STORM ISAAC REMAINS A FOCAL POINT WITH THE CENTER
CURRENTLY MOVING OVER CUBA.

THE LOCAL FORECAST AREA IS RIGHT ON THE EDGE OF THE LOW LEVEL
MOISTURE AND FOG THIS MORNING. THE RAP SEEMS TO HAVE A GOOD HANDLE
ON THIS MOISTURE AND SHOWS IT DISSIPATING BY 16Z. WITH THE
PLACEMENT OF THE MOISTURE...AND THAT THE MODELS ARE PUSHING THE
SURFACE LOW INTO THE PANHANDLE TO TIGHTEN THE PRESSURE GRADIENT
AND INCREASE THE WIND...THIS SEEMS LIKE A GOOD SOLUTION AND WILL
FOLLOW THIS LEAD INTO THE FORECAST FOR TODAY. WITH THE EARLY
DISMISSAL OF THE CLOUDS...AND RETURN FLOW...WOULD EXPECT STRONG
WARMING TODAY. TEMPERATURES DO WARM A FEW DEGREES ALOFT FROM WHAT
WAS OBSERVED ON SATURDAY...ALTHOUGH SOUNDINGS ARE INDICATING FULL
MIXING WON/T BE REALIZED. HOWEVER WITH THE EXTRA HOURS OF
SUNSHINE...BELIEVE 90S ARE ATTAINABLE FOR TODAY IN MOST LOCATIONS.

AN UPPER LEVEL SHORTWAVE TROUGH WAS OBSERVED EARLY THIS MORNING
MOVING INTO WYOMING. THIS ENERGY WILL BE THE FOCUS FOR
THUNDERSTORM DEVELOPMENT LATER TODAY. ALTHOUGH THE RETURN FLOW
DOESN/T LOOK PARTICULARLY STRONG UNTIL LATER THIS EVENING...BOTH
THE NAM AND GFS INCREASE PRECIPITABLE WATER TO VALUES OF AN INCH
OR MORE /120 PERCENT OF NORMAL/ OVER THE PANHANDLE /JUST FOR
REFERENCE THE 26.00Z LBF SOUNDING OBSERVED PW OF 0.67...WHILE RAP
HAD 0.43/. EVEN IF THE MOISTURE DOESN/T INCREASE THIS MUCH...THERE
SHOULD BE ENOUGH TO ALLOW FOR ISOLATED THUNDERSTORMS TO DEVELOP
OVER THE PANHANDLE LATER THIS AFTERNOON. SOUNDINGS SHOWING
INVERTED-V PROFILE SO WILL CONTINUE TO SEE THE THREATS FOR STRONG
AND ERRATIC WINDS FROM ANY STORMS...AS WELL AS LOW RAINFALL
AMOUNTS AND A CHANCE FOR SOME STRAY DRY LIGHTNING STRIKES. GOING
EASTWARD...MOISTURE INCREASE ISN/T AS SUBSTANTIAL...AND WITH LARGE
SCALE FORCING BEING LESS...THESE AREAS WILL STAY CAPPED SO WILL
KEEP AREAS EAST OF A LINE FROM NORTH PLATTE TO AINSWORTH DRY.

MONDAY WILL BE A SIMILAR DAY TO SUNDAY...WITH STRONG WARMING
EXPECTED WITH LOTS OF SUNSHINE AND HIGHS IN THE 90S. ALTHOUGH THE
RIDGE WILL BUILD INTO THE PLAINS THROUGH THE DAY...A DECENT
SHORTWAVE TROUGH IS SIGNALED TO PUSH OVER THE RIDGE AND INTO
NEBRASKA IN THE AFTERNOON. THIS SIGNAL WAS BEING PICKED UP BY THE
ECMWF/NAM/GEM-REGIONAL/SREF...AND WITH THE PROPER PLACEMENT OF THE
RIDGE...FELT IT WAS FITTING TO ADD A SLIGHT CHANCE OVER TH
PANHANDLE AND FAR NORTHWEST NEBRASKA.

TUESDAY AND WEDNESDAY SHOULD BE DRY...WITH THE UPPER LEVEL RIDGE
IN PLACE OVER THE HIGH PLAINS AND LOW PRESSURE AT THE SURFACE OFF
TO THE WEST. WINDS WILL BE BREEZY FROM THE SOUTH BOTH
DAYS...HOWEVER ALL MODELS ARE IN AGREEMENT WITH KEEPING MOISTURE
LIMITED...WITH DEWPOINTS IN THE 40S AND 50S. THE LACK OF MOISTURE
ADVECTION LIKELY HAS SOMETHING TO DO WITH TROPICAL STORM ISAAC
/LIKELY HURRICANE ISAAC BY THIS TIME/ TAKING MUCH OF THE AVAILABLE
MOISTURE. TUESDAY LOOKS TO BE THE WARMEST DAY OF THE WEEK...WITH
MID TO UPPER 90S EXPECTED...WITH WIDESPREAD 90S FOR WEDNESDAY AS
WELL.

FIRE WEATHER CONCERNS WILL BE ON THE FOREFRONT MONDAY THROUGH
WEDNESDAY...WITH THE COMBINATION OF THE DRY AIR AND BREEZY WINDS.
ALTHOUGH THE CURRENT FORECAST WOULD KEEP CONDITIONS OUT OF
CRITICAL CRITERIA...THE EXTREME DRYNESS OF THE FUELS COULD CAUSE
THE NEED FOR RED FLAG WARNINGS IF CONDITIONS ARE EXPECTED TO BE
CLOSE.

LONG TERM...THURSDAY THROUGH SATURDAY

THE UPPER LEVEL RIDGE HOLDS STRONG THROUGH THE SECOND HALF OF THE
WEEK. THIS WILL KEEP TEMPERATURES WARM AND ABOVE NORMAL IN THE
90S...WITH LITTLE IF ANY CHANCES FOR RAIN. AS THE RIDGE SHIFTS
EAST...COULD GET PACIFIC MOISTURE TO PUSH INTO THE NORTHERN AND
CENTRAL PLAINS...HOWEVER MODELS ARE NOT INDICATING ANY UPPER LEVEL
SUPPORT FOR ANY SHOWER OR STORM DEVELOPMENT SO KEPT THE FORECAST
DRY. IN TURN...THE STRENGTH OF THE RIDGE WILL LIKELY KEEP ANY
MOISTURE FROM ISAAC WELL EAST OF THE PLAINS. THERE HAS BEEN
CONSIDERABLE DIFFERENCES IN WHERE THE SYSTEM WILL TRACK ONCE
COMING ON-SHORE BUT AGAIN BECAUSE OF THE RIDGE OVER THE
PLAINS...IT WILL PROBABLY MOVE NORTH INTO THE OHIO RIVER VALLEY OR
EVEN ALONG THE EAST COAST.

AVIATION...

SOME PATCHY FOG DEVELOPING OVER NORTH CENTRAL NEBRASKA EARLY THIS
MORNING. MAIN AREA OF CONCERN WILL BE FROM KBBW TO KONL BUT
VISIBILITIES ALONG THE PLATTE RIVER VALLEY MAY BE REDUCED TO MVFR
AROUND SUNRISE. SOME ISOLATED THUNDERSTORMS MAY DEVELOP OVER THE
NEBRASKA PANHANDLE AND MOVE INTO THE WESTERN NEBRASKA SANDHILLS THIS
EVENING. ACTIVITY WILL STAY TO THE WEST OF A LINE FROM KVTN TO KLBF.
STRONG ERRATIC WINDS CAN BE EXPECTED IN THE VICINITY OF
THUNDERSTORMS.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...DENSE FOG ADVISORY UNTIL 10 AM CDT
THIS MORNING FOR NEZ007-009-010-026>029-037-038-059-070-071.

&&

$$

SHORT TERM/EXTENDED...POWER/BROOKS
AVIATION...POWER






AREA FORECAST DISCUSSION

NWS BUFFALO NY

 1128 AM EDT SUN AUG 26 2012

.SYNOPSIS...
HIGH PRESSURE WILL BRING ONE LAST VERY WARM DAY TODAY...WITH
INCREASING CLOUDS AND A SLIGHT CHANCE OF SHOWERS IN THE AFTERNOON.
THE CHANCE FOR SHOWERS WILL INCREASE FURTHER ON MONDAY AND MONDAY
NIGHT AS A COLD FRONT CROSSES THE REGION. A RETURN TO SEASONABLY
NORMAL TEMPERATURES AND DRY WEATHER IS EXPECTED FOR THE MIDDLE
PORTION OF THE COMING WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
MINOR CHANGES TO THE GRIDS...OTHERWISE FORECAST REMAINS ON TRACK.
PREVIOUS DISCUSSION FOLLOWS BELOW.

SURFACE HIGH PRESSURE IS CENTERED JUST OFF THE NEW ENGLAND COAST
WITH RIDGING EXTENDING BACK ACROSS NY INTO THE EASTERN OHIO VALLEY
THIS MORNING. ALOFT A CUT OFF LOW IS CYCLONICALLY SPINNING OVER THE
VIRGINIAS WITH SOME CONVECTION ACROSS THE DELMARVA. SATELLITE SHOWS
SOME SLOW SHIFT OF MID LAYER CLOUDS NORTHWARD INTO CENTRAL NY AND
THE INTERIOR SOUTHERN TIER.

LOOK FOR INCREASING CLOUDS THROUGH TODAY AS THE CUTOFF LOW CONTINUES TO
DRIFT NORTH. THE INCREASE IN CLOUD COVER AND SLIGHTLY COOLER
TEMPERATURES ALOFT ADVECTING INTO THE REGION ASSOCIATED WITH THE LOW
SHOULD YIELD COOLER TEMPERATURES...PARTICULARLY ACROSS THE SOUTHERN
TIER WHERE HIGHS SHOULD TOP OUT IN THE MID TO UPPER 70S. AREAS
FARTHER NORTH IN THE NIAGARA FRONTIER WILL LIKELY SEE ENOUGH
SUNSHINE TO CLIMB INTO THE LOW TO MID 80S AND THE WARMEST READINGS
WILL BE FOUND ACROSS THE NORTH COUNTRY WHERE SKIES SHOULD REMAIN
MOSTLY SUNNY THROUGHOUT THE DAY.

INCREASING LOW LEVEL MOISTURE WITH DEWPOINTS CREEPING BACK INTO THE
LOWER 60S AND NOMINAL COOLING ALOFT MAY BE JUST ENOUGH TO TRIGGER A
FEW SHOWERS...MAINLY ACROSS AREAS WEST OF THE GENESEE
VALLEY...HOWEVER GIVEN THE AMOUNT OF LINGERING DRY AIR...WIDESPREAD
CONVECTION IS NOT EXPECTED. THE 07Z RUN OF THE HRRR SHOWS SOME
SHOWERS POSSIBLE AROUND 20Z.

TONIGHT...ANY DIURNAL SHOWERS ACROSS WNY SHOULD END WITH HIGH
PRESSURE REMAINING OVER THE AREA. A COLD FRONT WILL CONTINUE TO
PRESS EAST TOWARD THE FORECAST AREA FROM MICHIGAN. CLOUD COVER WILL
INCREASING TOWARD OVERCAST WITH TEMPERATURES OVERNIGHT FALLING ONLY
INTO THE 60S...ON THE WARM SIDE WITH HIGHER HUMIDITY AROUND. FOG
WILL AGAIN BE LIMITED DUE TO WINDS NOT LOWERING TO CALM OVERNIGHT
AHEAD OF A COLD FRONT JUST TO THE WEST.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
FOCUS IN THE SHORT TERM PERIOD WILL BE ON A COLD FRONTAL PASSAGE ON
MONDAY AND ASSOCIATED RAIN CHANCES. THERE REMAINS SOME TIMING
DIFFERENCES WITH THE GFS A GOOD 6 HOURS FASTER THAN THE NAM. THE
SLOWER NAM SOLUTION HAS SOME SUPPORT FROM THE CANADIAN GEM AND SREF
ENSEMBLE MEAN. WITH A WEAK DECAYING CLOSED LOW OVER THE MID ATLANTIC
LIKELY PROVING TO BE A ROADBLOCK TO UPSTREAM SYSTEMS...HAVE FAVORED
THE SLOWER NAM TIMING. WITH THIS IN MIND THE BULK OF THE AREA WILL
BE RAIN FREE MONDAY MORNING WITH INCREASING CLOUDS.

LATER IN THE DAY MODEST MID LEVEL HEIGHT FALLS AND PVA WILL APPROACH
THE REGION...WITH THE ASSOCIATED COLD FRONT ENTERING WESTERN NY BY
LATE AFTERNOON OR EVENING...THEN SWEEPING ACROSS THE REST OF THE
AREA MONDAY NIGHT. A 70+ KNOT UPPER LEVEL JET WILL ALSO PROVIDE SOME
UPPER LEVEL DIVERGENCE AS THE RIGHT ENTRANCE REGION BECOMES SITUATED
OVER THE LOWER LAKES MONDAY AFTERNOON. SEVERAL DAYS OF SOUTHERLY
FLOW AHEAD OF THIS SYSTEM WILL PROVIDE A DECENT MOISTURE RETURN...
WITH PWAT OF AROUND 1.5 INCHES AND SURFACE DEWPOINTS IN THE MID 60S
ON AVERAGE. WITH THIS MOISTURE AND FORCING COMING INTO PLAY...HAVE
INCREASED POPS TO LIKELY FOR THE FRONTAL PASSAGE. THE TIMING OF THE
MOST WIDESPREAD PRECIP WILL BE LATE AFTERNOON AND EARLY EVENING IN
WESTERN NY...AND MAINLY MONDAY EVENING AND NIGHT FROM THE GENESEE
VALLEY EAST INTO CENTRAL AND NORTHERN NY.

INSTABILITY WILL ONLY BE MARGINAL GIVEN THE VERY WARM TEMPS
ALOFT...WITH SBCAPE OF ONLY 500-1000J/KG. A TALL/SKINNY CAPE PROFILE
AND ADEQUATE MOISTURE SUGGEST POTENTIAL FOR LOCAL HEAVY DOWNPOURS
WITH ANY STORMS THAT FORM. THE WEAK INSTABILITY AND RELATIVELY WEAK
WIND FIELDS WILL KEEP STORMS POORLY ORGANIZED WITH LITTLE POTENTIAL
FOR ANY WIND OR HAIL. MONDAY WILL STILL BE QUITE WARM WITH 850MB
TEMPS OF AROUND +15C. WITH THE EXPECTATION THAT RAIN WILL HOLD OFF
UNTIL THE AFTERNOON...HAVE GONE ABOVE ALL MODEL GUIDANCE WITH HIGHS
IN THE MID 80S IN MANY LOCATIONS...ALONG WITH INCREASED HUMIDITY.

THE COLD FRONT AND ASSOCIATED RAIN WILL BE EAST OF THE CWA BY
DAYBREAK TUESDAY. A SECONDARY COLD FRONT AND ASSOCIATED MID LEVEL
SHORTWAVE WILL DROP INTO THE NORTH COUNTRY DURING THE DAY TUESDAY
AND MAY TOUCH OFF A FEW MORE WIDELY SCATTERED LIGHT SHOWERS. SOME
LIMITED MOISTURE ALONG AND AHEAD OF THIS SECONDARY TROUGH WILL ALSO
PRODUCE SOME DIURNAL CUMULUS...WITH A MIX OF SUN AND CLOUDS IN MANY
LOCATIONS. A SOMEWHAT COOLER AIRMASS WILL BUILD INTO THE AREA WITH
TEMPERATURES DROPPING BACK CLOSER TO AVERAGE. EXPECT HIGHS IN THE
MID TO UPPER 70S IN MOST LOCATIONS.

TUESDAY EVENING THE SECONDARY COLD FRONT WILL DROP SOUTH ACROSS THE
AREA WITH A PERIOD OF CLOUD COVER...FOLLOWED BY CLEARING SKIES
OVERNIGHT AND ADDITIONAL COLD AIR ADVECTION. THIS WILL ALLOW TEMPS
TO DROP INTO THE MID 50S ON THE LAKE PLAINS AND AROUND 50 IN THE
COOLER SOUTHERN TIER VALLEYS AND TUG HILL REGION.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ON WEDNESDAY A LONGWAVE TROUGH WILL BECOME ESTABLISHED ACROSS
SOUTHEAST CANADA WITH A NORTHWEST FLOW OF COOLER AIR DIRECTED INTO
THE GREAT LAKES. SURFACE HIGH PRESSURE WILL BUILD INTO THE OHIO
VALLEY AND GREAT LAKES WITH A RETURN TO SUNSHINE. 850MB TEMPS OF
ONLY AROUND +8C WILL SUPPORT HIGHS IN THE MID 70S ACROSS LOWER
ELEVATIONS AND AROUND 70 ACROSS HIGHER TERRAIN. HIGH PRESSURE
OVERHEAD WEDNESDAY NIGHT WILL PROVIDE CLEAR SKIES AND A SEASONABLY
COOL NIGHT WITH MID 50S ON THE LAKE PLAINS AND A FEW UPPER 40S IN
THE COOLER SOUTHERN TIER VALLEYS AND EAST OF LAKE ONTARIO.

BY THURSDAY AND FRIDAY HIGH PRESSURE WILL BUILD QUICKLY TO THE EAST
COAST AND ALLOW SOUTHWEST RETURN FLOW TO INCREASE. 850MB TEMPS RISE
TO AROUND +14C THURSDAY AFTERNOON ON THE LATEST ECMWF...A LITTLE
WARMER EVEN ON THE GFS. IF THE TIMING HOLDS THIS WILL SUPPORT HIGHS
IN THE LOW TO MID 80S. BY FRIDAY A CENTRAL PLAINS ELEVATED MIXED
LAYER /EML/ PLUME BECOMES CAPTURED BY THE NEXT SYSTEM AND IS
ADVECTED EAST ALL THE WAY INTO THE LOWER LAKES WITH 850MB TEMPS
SOARING TO AROUND +20C. IF THIS VERIFIES...TEMPERATURES WILL MAKE IT
INTO THE 90S ONCE AGAIN WITH HEAT RETURNING. BOTH DAYS WILL BE DRY
AS AN UPPER LEVEL RIDGE SHIFTS EAST ACROSS THE PLAINS AND INTO THE
OHIO VALLEY AND GREAT LAKES.

BY SATURDAY FORECAST UNCERTAINTY INCREASES WITH RESPECT TO THE
TIMING AND PLACEMENT OF THE REMNANTS OF ISAAC. THE LATEST GFS
SPREADS SOME RAIN TOWARDS THE NY/PA BORDER...WHILE THE ECMWF KEEPS
THE SYSTEM CUTOFF AND WELL SOUTH OF THE AREA. PREVIOUS FORECAST HAD
SOME LOW CHANCE POPS AND WILL KEEP THOSE FOR NOW. THE FORECAST FOR
NEXT WEEKEND WILL BE UNCERTAIN FOR SEVERAL DAYS TO COME UNTIL MODEL
GUIDANCE COMES INTO BETTER AGREEMENT WITH THE TRACK OF ISAAC...AND
ITS EVENTUAL INTERACTION WITH THE MID LATITUDE WESTERLIES.

&&

.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
VISIBLE SATELLITE SHOWS RAPID DEVELOPMENT OF CLOUD COVER ACROSS
WESTERN NY LATE THIS MORNING. THE RESULT OF MOISTURE STREAMING
NORTHWARD FROM THE UPPER LOW OVER VA/MD. RADAR IS ALSO PICKING UP
A FEW LIGHT SHOWERS OR SPRINKLES OVER THE NIAGARA FRONTIER AND
WESTERN SOUTHERN TIER. EXPECT MAINLY VFR CLOUD COVER OVER MOST TAF
LOCATIONS WITH A CHANCE OF -SHRA...GENERALLY FROM THE GENESEE
VALLEY WEST. 12Z HRRR MODEL IS HIGHLIGHTING THIS NICELY. THE LIGHT
SOUTHERLY BREEZE SHOULD PREVENT MOST FOG FORMATION TONIGHT EXCEPT
IN SHELTERED VALLEYS.

OUTLOOK...
MONDAY AND MONDAY NIGHT...MAINLY VFR WITH A CHC OF SHRA/TSRA.
TUESDAY...VFR. CHC SHRA MAINLY EAST.
WEDNESDAY AND THURSDAY...VFR.

&&

.MARINE...
SOUTHERLY WINDS INCREASING TO 10 TO 15 KNOTS OVER THE LAKES ARE
PRODUCING CHOPPY CONDITIONS. WITH WAVES UP TO THREE FEET TONIGHT
ACROSS EASTERN LAKE ONTARIO. OTHERWISE GOOD BOATING CONDITIONS
EXPECTED ON THE LAKES TODAY.

A COLD FRONT WILL CROSS THE LAKES MONDAY AFTERNOON AND EVENING
BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. WESTERLY WINDS IN
THE WAKE OF THE FRONT WILL LIKELY RESULT IN SMALL CRAFT CONDITIONS
MONDAY AFTERNOON AND MONDAY NIGHT BEFORE HIGH PRESSURE BUILDS BACK
INTO THE REGION TUESDAY.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...SMITH
NEAR TERM...AR/SMITH
SHORT TERM...HITCHCOCK
LONG TERM...HITCHCOCK
AVIATION...AR/SMITH
MARINE...HITCHCOCK/SMITH








AREA FORECAST DISCUSSION

NWS BUFFALO NY

 1030 AM EDT SUN AUG 26 2012

.SYNOPSIS...
HIGH PRESSURE WILL BRING ONE LAST VERY WARM DAY TODAY...WITH
INCREASING CLOUDS AND A SLIGHT CHANCE OF SHOWERS IN THE AFTERNOON.
THE CHANCE FOR SHOWERS WILL INCREASE FURTHER ON MONDAY AND MONDAY
NIGHT AS A COLD FRONT CROSSES THE REGION. A RETURN TO SEASONABLY
NORMAL TEMPERATURES AND DRY WEATHER IS EXPECTED FOR THE MIDDLE
PORTION OF THE COMING WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
MINOR CHANGES TO THE GRIDS...OTHERWISE FORECAST REMAINS ON TRACK.
PREVIOUS DISCUSSION FOLLOWS BELOW.

SURFACE HIGH PRESSURE IS CENTERED JUST OFF THE NEW ENGLAND COAST
WITH RIDGING EXTENDING BACK ACROSS NY INTO THE EASTERN OHIO VALLEY
THIS MORNING. ALOFT A CUT OFF LOW IS CYCLONICALLY SPINNING OVER THE
VIRGINIAS WITH SOME CONVECTION ACROSS THE DELMARVA. SATELLITE SHOWS
SOME SLOW SHIFT OF MID LAYER CLOUDS NORTHWARD INTO CENTRAL NY AND
THE INTERIOR SOUTHERN TIER.

LOOK FOR INCREASING CLOUDS THROUGH TODAY AS THE CUTOFF LOW CONTINUES TO
DRIFT NORTH. THE INCREASE IN CLOUD COVER AND SLIGHTLY COOLER
TEMPERATURES ALOFT ADVECTING INTO THE REGION ASSOCIATED WITH THE LOW
SHOULD YIELD COOLER TEMPERATURES...PARTICULARLY ACROSS THE SOUTHERN
TIER WHERE HIGHS SHOULD TOP OUT IN THE MID TO UPPER 70S. AREAS
FARTHER NORTH IN THE NIAGARA FRONTIER WILL LIKELY SEE ENOUGH
SUNSHINE TO CLIMB INTO THE LOW TO MID 80S AND THE WARMEST READINGS
WILL BE FOUND ACROSS THE NORTH COUNTRY WHERE SKIES SHOULD REMAIN
MOSTLY SUNNY THROUGHOUT THE DAY.

INCREASING LOW LEVEL MOISTURE WITH DEWPOINTS CREEPING BACK INTO THE
LOWER 60S AND NOMINAL COOLING ALOFT MAY BE JUST ENOUGH TO TRIGGER A
FEW SHOWERS...MAINLY ACROSS AREAS WEST OF THE GENESEE
VALLEY...HOWEVER GIVEN THE AMOUNT OF LINGERING DRY AIR...WIDESPREAD
CONVECTION IS NOT EXPECTED. THE 07Z RUN OF THE HRRR SHOWS SOME
SHOWERS POSSIBLE AROUND 20Z.

TONIGHT...ANY DIURNAL SHOWERS ACROSS WNY SHOULD END WITH HIGH
PRESSURE REMAINING OVER THE AREA. A COLD FRONT WILL CONTINUE TO
PRESS EAST TOWARD THE FORECAST AREA FROM MICHIGAN. CLOUD COVER WILL
INCREASING TOWARD OVERCAST WITH TEMPERATURES OVERNIGHT FALLING ONLY
INTO THE 60S...ON THE WARM SIDE WITH HIGHER HUMIDITY AROUND. FOG
WILL AGAIN BE LIMITED DUE TO WINDS NOT LOWERING TO CALM OVERNIGHT
AHEAD OF A COLD FRONT JUST TO THE WEST.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
FOCUS IN THE SHORT TERM PERIOD WILL BE ON A COLD FRONTAL PASSAGE ON
MONDAY AND ASSOCIATED RAIN CHANCES. THERE REMAINS SOME TIMING
DIFFERENCES WITH THE GFS A GOOD 6 HOURS FASTER THAN THE NAM. THE
SLOWER NAM SOLUTION HAS SOME SUPPORT FROM THE CANADIAN GEM AND SREF
ENSEMBLE MEAN. WITH A WEAK DECAYING CLOSED LOW OVER THE MID ATLANTIC
LIKELY PROVING TO BE A ROADBLOCK TO UPSTREAM SYSTEMS...HAVE FAVORED
THE SLOWER NAM TIMING. WITH THIS IN MIND THE BULK OF THE AREA WILL
BE RAIN FREE MONDAY MORNING WITH INCREASING CLOUDS.

LATER IN THE DAY MODEST MID LEVEL HEIGHT FALLS AND PVA WILL APPROACH
THE REGION...WITH THE ASSOCIATED COLD FRONT ENTERING WESTERN NY BY
LATE AFTERNOON OR EVENING...THEN SWEEPING ACROSS THE REST OF THE
AREA MONDAY NIGHT. A 70+ KNOT UPPER LEVEL JET WILL ALSO PROVIDE SOME
UPPER LEVEL DIVERGENCE AS THE RIGHT ENTRANCE REGION BECOMES SITUATED
OVER THE LOWER LAKES MONDAY AFTERNOON. SEVERAL DAYS OF SOUTHERLY
FLOW AHEAD OF THIS SYSTEM WILL PROVIDE A DECENT MOISTURE RETURN...
WITH PWAT OF AROUND 1.5 INCHES AND SURFACE DEWPOINTS IN THE MID 60S
ON AVERAGE. WITH THIS MOISTURE AND FORCING COMING INTO PLAY...HAVE
INCREASED POPS TO LIKELY FOR THE FRONTAL PASSAGE. THE TIMING OF THE
MOST WIDESPREAD PRECIP WILL BE LATE AFTERNOON AND EARLY EVENING IN
WESTERN NY...AND MAINLY MONDAY EVENING AND NIGHT FROM THE GENESEE
VALLEY EAST INTO CENTRAL AND NORTHERN NY.

INSTABILITY WILL ONLY BE MARGINAL GIVEN THE VERY WARM TEMPS
ALOFT...WITH SBCAPE OF ONLY 500-1000J/KG. A TALL/SKINNY CAPE PROFILE
AND ADEQUATE MOISTURE SUGGEST POTENTIAL FOR LOCAL HEAVY DOWNPOURS
WITH ANY STORMS THAT FORM. THE WEAK INSTABILITY AND RELATIVELY WEAK
WIND FIELDS WILL KEEP STORMS POORLY ORGANIZED WITH LITTLE POTENTIAL
FOR ANY WIND OR HAIL. MONDAY WILL STILL BE QUITE WARM WITH 850MB
TEMPS OF AROUND +15C. WITH THE EXPECTATION THAT RAIN WILL HOLD OFF
UNTIL THE AFTERNOON...HAVE GONE ABOVE ALL MODEL GUIDANCE WITH HIGHS
IN THE MID 80S IN MANY LOCATIONS...ALONG WITH INCREASED HUMIDITY.

THE COLD FRONT AND ASSOCIATED RAIN WILL BE EAST OF THE CWA BY
DAYBREAK TUESDAY. A SECONDARY COLD FRONT AND ASSOCIATED MID LEVEL
SHORTWAVE WILL DROP INTO THE NORTH COUNTRY DURING THE DAY TUESDAY
AND MAY TOUCH OFF A FEW MORE WIDELY SCATTERED LIGHT SHOWERS. SOME
LIMITED MOISTURE ALONG AND AHEAD OF THIS SECONDARY TROUGH WILL ALSO
PRODUCE SOME DIURNAL CUMULUS...WITH A MIX OF SUN AND CLOUDS IN MANY
LOCATIONS. A SOMEWHAT COOLER AIRMASS WILL BUILD INTO THE AREA WITH
TEMPERATURES DROPPING BACK CLOSER TO AVERAGE. EXPECT HIGHS IN THE
MID TO UPPER 70S IN MOST LOCATIONS.

TUESDAY EVENING THE SECONDARY COLD FRONT WILL DROP SOUTH ACROSS THE
AREA WITH A PERIOD OF CLOUD COVER...FOLLOWED BY CLEARING SKIES
OVERNIGHT AND ADDITIONAL COLD AIR ADVECTION. THIS WILL ALLOW TEMPS
TO DROP INTO THE MID 50S ON THE LAKE PLAINS AND AROUND 50 IN THE
COOLER SOUTHERN TIER VALLEYS AND TUG HILL REGION.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ON WEDNESDAY A LONGWAVE TROUGH WILL BECOME ESTABLISHED ACROSS
SOUTHEAST CANADA WITH A NORTHWEST FLOW OF COOLER AIR DIRECTED INTO
THE GREAT LAKES. SURFACE HIGH PRESSURE WILL BUILD INTO THE OHIO
VALLEY AND GREAT LAKES WITH A RETURN TO SUNSHINE. 850MB TEMPS OF
ONLY AROUND +8C WILL SUPPORT HIGHS IN THE MID 70S ACROSS LOWER
ELEVATIONS AND AROUND 70 ACROSS HIGHER TERRAIN. HIGH PRESSURE
OVERHEAD WEDNESDAY NIGHT WILL PROVIDE CLEAR SKIES AND A SEASONABLY
COOL NIGHT WITH MID 50S ON THE LAKE PLAINS AND A FEW UPPER 40S IN
THE COOLER SOUTHERN TIER VALLEYS AND EAST OF LAKE ONTARIO.

BY THURSDAY AND FRIDAY HIGH PRESSURE WILL BUILD QUICKLY TO THE EAST
COAST AND ALLOW SOUTHWEST RETURN FLOW TO INCREASE. 850MB TEMPS RISE
TO AROUND +14C THURSDAY AFTERNOON ON THE LATEST ECMWF...A LITTLE
WARMER EVEN ON THE GFS. IF THE TIMING HOLDS THIS WILL SUPPORT HIGHS
IN THE LOW TO MID 80S. BY FRIDAY A CENTRAL PLAINS ELEVATED MIXED
LAYER /EML/ PLUME BECOMES CAPTURED BY THE NEXT SYSTEM AND IS
ADVECTED EAST ALL THE WAY INTO THE LOWER LAKES WITH 850MB TEMPS
SOARING TO AROUND +20C. IF THIS VERIFIES...TEMPERATURES WILL MAKE IT
INTO THE 90S ONCE AGAIN WITH HEAT RETURNING. BOTH DAYS WILL BE DRY
AS AN UPPER LEVEL RIDGE SHIFTS EAST ACROSS THE PLAINS AND INTO THE
OHIO VALLEY AND GREAT LAKES.

BY SATURDAY FORECAST UNCERTAINTY INCREASES WITH RESPECT TO THE
TIMING AND PLACEMENT OF THE REMNANTS OF ISAAC. THE LATEST GFS
SPREADS SOME RAIN TOWARDS THE NY/PA BORDER...WHILE THE ECMWF KEEPS
THE SYSTEM CUTOFF AND WELL SOUTH OF THE AREA. PREVIOUS FORECAST HAD
SOME LOW CHANCE POPS AND WILL KEEP THOSE FOR NOW. THE FORECAST FOR
NEXT WEEKEND WILL BE UNCERTAIN FOR SEVERAL DAYS TO COME UNTIL MODEL
GUIDANCE COMES INTO BETTER AGREEMENT WITH THE TRACK OF ISAAC...AND
ITS EVENTUAL INTERACTION WITH THE MID LATITUDE WESTERLIES.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD AS THE AREA
REMAINS UNDER THE INFLUENCE OF HIGH PRESSURE. INCREASING
MOISTURE FROM THE SOUTHEAST WILL USHER IN INCREASED VFR CLOUD COVER
LATER TODAY WITH A CHANCE OF SHRA AFTER 18Z GENERALLY FROM THE
GENESEE VALLEY WEST. 07Z HRRR MODEL IS HIGHLIGHTING THIS. THE LIGHT
SOUTHERLY BREEZE SHOULD PREVENT MOST FOG FORMATION TONIGHT EXCEPT IN
SHELTERED VALLEYS.

OUTLOOK...
MONDAY AND MONDAY NIGHT...MAINLY VFR WITH A CHC OF SHRA/TSRA.
TUESDAY...VFR. CHC SHRA MAINLY EAST.
WEDNESDAY AND THURSDAY...VFR.

&&

.MARINE...
SOUTHERLY WINDS INCREASING TO 10 TO 15 KNOTS OVER THE LAKES ARE
PRODUCING CHOPPY CONDITIONS. WITH WAVES UP TO THREE FEET TONIGHT
ACROSS EASTERN LAKE ONTARIO. OTHERWISE GOOD BOATING CONDITIONS
EXPECTED ON THE LAKES TODAY.

A COLD FRONT WILL CROSS THE LAKES MONDAY AFTERNOON AND EVENING
BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. WESTERLY WINDS IN
THE WAKE OF THE FRONT WILL LIKELY RESULT IN SMALL CRAFT CONDITIONS
MONDAY AFTERNOON AND MONDAY NIGHT BEFORE HIGH PRESSURE BUILDS BACK
INTO THE REGION TUESDAY.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...SMITH
NEAR TERM...AR/SMITH
SHORT TERM...HITCHCOCK
LONG TERM...HITCHCOCK
AVIATION...SMITH
MARINE...HITCHCOCK/SMITH








AREA FORECAST DISCUSSION

NWS BUFFALO NY

 757 AM EDT SUN AUG 26 2012

.SYNOPSIS...
HIGH PRESSURE WILL BRING ONE LAST VERY WARM DAY TODAY...WITH
INCREASING CLOUDS AND A SLIGHT CHANCE OF SHOWERS IN THE AFTERNOON.
THE CHANCE FOR SHOWERS WILL INCREASE FURTHER ON MONDAY AND MONDAY
NIGHT AS A COLD FRONT CROSSES THE REGION. A RETURN TO SEASONABLY
NORMAL TEMPERATURES AND DRY WEATHER IS EXPECTED FOR THE MIDDLE
PORTION OF THE COMING WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
SURFACE HIGH PRESSURE IS CENTERED JUST OFF THE NEW ENGLAND COAST
WITH RIDGING EXTENDING BACK ACROSS NY INTO THE EASTERN OHIO VALLEY
THIS MORNING. ALOFT A CUT OFF LOW IS CYCLONICALLY SPINNING OVER THE
VIRGINIAS WITH SOME CONVECTION ACROSS THE DELMARVA. SATELLITE SHOWS
SOME SLOW SHIFT OF MID LAYER CLOUDS NORTHWARD INTO CENTRAL NY AND
THE INTERIOR SOUTHERN TIER. OTHERWISE CLEAR SKIES OUTSIDE OF VERY
LIMITED FOG BEING REPORTED AT BFD AND ELZ.

LOOK FOR INCREASING CLOUDS THROUGH TODAY AS THE CUTOFF LOW CONTINUES TO
DRIFT NORTH. THE INCREASE IN CLOUD COVER AND SLIGHTLY COOLER
TEMPERATURES ALOFT ADVECTING INTO THE REGION ASSOCIATED WITH THE LOW
SHOULD YIELD COOLER TEMPERATURES...PARTICULARLY ACROSS THE SOUTHERN
TIER WHERE HIGHS SHOULD TOP OUT IN THE MID TO UPPER 70S. AREAS
FARTHER NORTH IN THE NIAGARA FRONTIER WILL LIKELY SEE ENOUGH
SUNSHINE TO CLIMB INTO THE LOW TO MID 80S AND THE WARMEST READINGS
WILL BE FOUND ACROSS THE NORTH COUNTRY WHERE SKIES SHOULD REMAIN
MOSTLY SUNNY THROUGHOUT THE DAY.

INCREASING LOW LEVEL MOISTURE WITH DEWPOINTS CREEPING BACK INTO THE
LOWER 60S AND NOMINAL COOLING ALOFT MAY BE JUST ENOUGH TO TRIGGER A
FEW SHOWERS...MAINLY ACROSS AREAS WEST OF THE GENESEE
VALLEY...HOWEVER GIVEN THE AMOUNT OF LINGERING DRY AIR...WIDESPREAD
CONVECTION IS NOT EXPECTED. THE 07Z RUN OF THE HRRR SHOWS SOME
SHOWERS POSSIBLE AROUND 20Z.

TONIGHT...ANY DIURNAL SHOWERS ACROSS WNY SHOULD END WITH HIGH
PRESSURE REMAINING OVER THE AREA. A COLD FRONT WILL CONTINUE TO
PRESS EAST TOWARD THE FORECAST AREA FROM MICHIGAN. CLOUD COVER WILL
INCREASING TOWARD OVERCAST WITH TEMPERATURES OVERNIGHT FALLING ONLY
INTO THE 60S...ON THE WARM SIDE WITH HIGHER HUMIDITY AROUND. FOG
WILL AGAIN BE LIMITED DUE TO WINDS NOT LOWERING TO CALM OVERNIGHT
AHEAD OF A COLD FRONT JUST TO THE WEST.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
FOCUS IN THE SHORT TERM PERIOD WILL BE ON A COLD FRONTAL PASSAGE ON
MONDAY AND ASSOCIATED RAIN CHANCES. THERE REMAINS SOME TIMING
DIFFERENCES WITH THE GFS A GOOD 6 HOURS FASTER THAN THE NAM. THE
SLOWER NAM SOLUTION HAS SOME SUPPORT FROM THE CANADIAN GEM AND SREF
ENSEMBLE MEAN. WITH A WEAK DECAYING CLOSED LOW OVER THE MID ATLANTIC
LIKELY PROVING TO BE A ROADBLOCK TO UPSTREAM SYSTEMS...HAVE FAVORED
THE SLOWER NAM TIMING. WITH THIS IN MIND THE BULK OF THE AREA WILL
BE RAIN FREE MONDAY MORNING WITH INCREASING CLOUDS.

LATER IN THE DAY MODEST MID LEVEL HEIGHT FALLS AND PVA WILL APPROACH
THE REGION...WITH THE ASSOCIATED COLD FRONT ENTERING WESTERN NY BY
LATE AFTERNOON OR EVENING...THEN SWEEPING ACROSS THE REST OF THE
AREA MONDAY NIGHT. A 70+ KNOT UPPER LEVEL JET WILL ALSO PROVIDE SOME
UPPER LEVEL DIVERGENCE AS THE RIGHT ENTRANCE REGION BECOMES SITUATED
OVER THE LOWER LAKES MONDAY AFTERNOON. SEVERAL DAYS OF SOUTHERLY
FLOW AHEAD OF THIS SYSTEM WILL PROVIDE A DECENT MOISTURE RETURN...
WITH PWAT OF AROUND 1.5 INCHES AND SURFACE DEWPOINTS IN THE MID 60S
ON AVERAGE. WITH THIS MOISTURE AND FORCING COMING INTO PLAY...HAVE
INCREASED POPS TO LIKELY FOR THE FRONTAL PASSAGE. THE TIMING OF THE
MOST WIDESPREAD PRECIP WILL BE LATE AFTERNOON AND EARLY EVENING IN
WESTERN NY...AND MAINLY MONDAY EVENING AND NIGHT FROM THE GENESEE
VALLEY EAST INTO CENTRAL AND NORTHERN NY.

INSTABILITY WILL ONLY BE MARGINAL GIVEN THE VERY WARM TEMPS
ALOFT...WITH SBCAPE OF ONLY 500-1000J/KG. A TALL/SKINNY CAPE PROFILE
AND ADEQUATE MOISTURE SUGGEST POTENTIAL FOR LOCAL HEAVY DOWNPOURS
WITH ANY STORMS THAT FORM. THE WEAK INSTABILITY AND RELATIVELY WEAK
WIND FIELDS WILL KEEP STORMS POORLY ORGANIZED WITH LITTLE POTENTIAL
FOR ANY WIND OR HAIL. MONDAY WILL STILL BE QUITE WARM WITH 850MB
TEMPS OF AROUND +15C. WITH THE EXPECTATION THAT RAIN WILL HOLD OFF
UNTIL THE AFTERNOON...HAVE GONE ABOVE ALL MODEL GUIDANCE WITH HIGHS
IN THE MID 80S IN MANY LOCATIONS...ALONG WITH INCREASED HUMIDITY.

THE COLD FRONT AND ASSOCIATED RAIN WILL BE EAST OF THE CWA BY
DAYBREAK TUESDAY. A SECONDARY COLD FRONT AND ASSOCIATED MID LEVEL
SHORTWAVE WILL DROP INTO THE NORTH COUNTRY DURING THE DAY TUESDAY
AND MAY TOUCH OFF A FEW MORE WIDELY SCATTERED LIGHT SHOWERS. SOME
LIMITED MOISTURE ALONG AND AHEAD OF THIS SECONDARY TROUGH WILL ALSO
PRODUCE SOME DIURNAL CUMULUS...WITH A MIX OF SUN AND CLOUDS IN MANY
LOCATIONS. A SOMEWHAT COOLER AIRMASS WILL BUILD INTO THE AREA WITH
TEMPERATURES DROPPING BACK CLOSER TO AVERAGE. EXPECT HIGHS IN THE
MID TO UPPER 70S IN MOST LOCATIONS.

TUESDAY EVENING THE SECONDARY COLD FRONT WILL DROP SOUTH ACROSS THE
AREA WITH A PERIOD OF CLOUD COVER...FOLLOWED BY CLEARING SKIES
OVERNIGHT AND ADDITIONAL COLD AIR ADVECTION. THIS WILL ALLOW TEMPS
TO DROP INTO THE MID 50S ON THE LAKE PLAINS AND AROUND 50 IN THE
COOLER SOUTHERN TIER VALLEYS AND TUG HILL REGION.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ON WEDNESDAY A LONGWAVE TROUGH WILL BECOME ESTABLISHED ACROSS
SOUTHEAST CANADA WITH A NORTHWEST FLOW OF COOLER AIR DIRECTED INTO
THE GREAT LAKES. SURFACE HIGH PRESSURE WILL BUILD INTO THE OHIO
VALLEY AND GREAT LAKES WITH A RETURN TO SUNSHINE. 850MB TEMPS OF
ONLY AROUND +8C WILL SUPPORT HIGHS IN THE MID 70S ACROSS LOWER
ELEVATIONS AND AROUND 70 ACROSS HIGHER TERRAIN. HIGH PRESSURE
OVERHEAD WEDNESDAY NIGHT WILL PROVIDE CLEAR SKIES AND A SEASONABLY
COOL NIGHT WITH MID 50S ON THE LAKE PLAINS AND A FEW UPPER 40S IN
THE COOLER SOUTHERN TIER VALLEYS AND EAST OF LAKE ONTARIO.

BY THURSDAY AND FRIDAY HIGH PRESSURE WILL BUILD QUICKLY TO THE EAST
COAST AND ALLOW SOUTHWEST RETURN FLOW TO INCREASE. 850MB TEMPS RISE
TO AROUND +14C THURSDAY AFTERNOON ON THE LATEST ECMWF...A LITTLE
WARMER EVEN ON THE GFS. IF THE TIMING HOLDS THIS WILL SUPPORT HIGHS
IN THE LOW TO MID 80S. BY FRIDAY A CENTRAL PLAINS ELEVATED MIXED
LAYER /EML/ PLUME BECOMES CAPTURED BY THE NEXT SYSTEM AND IS
ADVECTED EAST ALL THE WAY INTO THE LOWER LAKES WITH 850MB TEMPS
SOARING TO AROUND +20C. IF THIS VERIFIES...TEMPERATURES WILL MAKE IT
INTO THE 90S ONCE AGAIN WITH HEAT RETURNING. BOTH DAYS WILL BE DRY
AS AN UPPER LEVEL RIDGE SHIFTS EAST ACROSS THE PLAINS AND INTO THE
OHIO VALLEY AND GREAT LAKES.

BY SATURDAY FORECAST UNCERTAINTY INCREASES WITH RESPECT TO THE
TIMING AND PLACEMENT OF THE REMNANTS OF ISAAC. THE LATEST GFS
SPREADS SOME RAIN TOWARDS THE NY/PA BORDER...WHILE THE ECMWF KEEPS
THE SYSTEM CUTOFF AND WELL SOUTH OF THE AREA. PREVIOUS FORECAST HAD
SOME LOW CHANCE POPS AND WILL KEEP THOSE FOR NOW. THE FORECAST FOR
NEXT WEEKEND WILL BE UNCERTAIN FOR SEVERAL DAYS TO COME UNTIL MODEL
GUIDANCE COMES INTO BETTER AGREEMENT WITH THE TRACK OF ISAAC...AND
ITS EVENTUAL INTERACTION WITH THE MID LATITUDE WESTERLIES.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD AS THE AREA
REMAINS UNDER THE INFLUENCE OF HIGH PRESSURE. INCREASING
MOISTURE FROM THE SOUTHEAST WILL USHER IN INCREASED VFR CLOUD COVER
LATER TODAY WITH A CHANCE OF SHRA AFTER 18Z GENERALLY FROM THE
GENESEE VALLEY WEST. 07Z HRRR MODEL IS HIGHLIGHTING THIS. THE LIGHT
SOUTHERLY BREEZE SHOULD PREVENT MOST FOG FORMATION TONIGHT EXCEPT IN
SHELTERED VALLEYS.

OUTLOOK...
MONDAY AND MONDAY NIGHT...MAINLY VFR WITH A CHC OF SHRA/TSRA.
TUESDAY...VFR. CHC SHRA MAINLY EAST.
WEDNESDAY AND THURSDAY...VFR.

&&

.MARINE...
SOUTHERLY WINDS INCREASING TO 10 TO 15 KNOTS OVER THE LAKES ARE
PRODUCING CHOPPY CONDITIONS. WITH WAVES UP TO THREE FEET TONIGHT
ACROSS EASTERN LAKE ONTARIO. OTHERWISE GOOD BOATING CONDITIONS
EXPECTED ON THE LAKES TODAY.

A COLD FRONT WILL CROSS THE LAKES MONDAY AFTERNOON AND EVENING
BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. WESTERLY WINDS IN
THE WAKE OF THE FRONT WILL LIKELY RESULT IN SMALL CRAFT CONDITIONS
MONDAY AFTERNOON AND MONDAY NIGHT BEFORE HIGH PRESSURE BUILDS BACK
INTO THE REGION TUESDAY.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...SMITH
NEAR TERM...JJR/SMITH
SHORT TERM...HITCHCOCK
LONG TERM...HITCHCOCK
AVIATION...SMITH
MARINE...HITCHCOCK/SMITH









AREA FORECAST DISCUSSION

NWS BLACKSBURG VA

 1018 AM EDT SUN AUG 26 2012

.SYNOPSIS...
LOW PRESSURE OVER EASTERN VIRGINIA WILL CONTINUE TO DRIFT NORTH
THIS AFTERNOON AND SLOWLY DISSIPATE. WEAK HIGH PRESSURE SHOULD
SLIDE IN BEHIND THE SYSTEM TONIGHT AND MONDAY. A COLD FRONT WILL
DROP IN FROM THE NORTHWEST TUESDAY BEFORE DRIFTING SOUTH INTO THE
CAROLINAS BY MIDWEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 955 AM EDT SUNDAY...

UPPER VORT REMAINS STUCK ACROSS THE NE CORNER OF THE AREA THIS
MORNING...BASICALLY JUST N/NW OF LYH. CLOUD CANOPY WITH THIS
FEATURE AGAIN EXPANDING BACK TO THE SW ALTHOUGH MORNING SOUNDINGS
SHOW THE DEEPER MOISTURE NOW TO THE NE WHERE BETTER INSTABILITY
AND BANDS OF SHRA PERSIST. GUIDANCE SHOWS THIS UPPER FEATURE
GRADUALLY PULLING OUT TO THE NE THIS AFTERNOON ALLOWING CLOUDS TO
DIMINISH AS DRIER AIR SWINGS IN FROM THE NW. HOWEVER STILL APPEARS
ENOUGH LOW LEVEL RH GIVEN HEATING TO PRODUCE ADDITIONAL WIDELY
SCTD BANDS OF SHRA/ISOLD TSRA PENDING OVERALL DEGREE OF HEATING.
THINK BEST CHANCE OF STORMS WILL BE ACROSS THE NW ON THE CURRENT
PERIPHERY OF THE CLOUD AXIS AND CLOSER TO THE VORT CENTER OVER THE
NE IF MORE HEATING DOES DEVELOP. LATEST LOCAL WRF AND THE HRRR DO
HAVE A FEW SHRA ACROSS THE NORTH HALF SO KEEPING SOME SCTD POPS
GOING MAINLY ALONG/NORTH OF HIWAY 460. OTRW WILL RETROGRADE
CLOUDS A BIT MORE TO THE SW INITIALLY THEN HAVE MORE OF A MOSTLY
SUNNY FLAVOR SOUTH TO PC NORTH PER LATEST NAM MOISTURE FIELDS.
TEMPS A BIT MORE TRICKY AS COULD STAY CLOSER TO THE LOW/MID 70S NE
IF CLOUDS LINGER WHILE UPPER 70S/LOW 80S LOOK ON TRACK WITH
MORNING THICKNESS ELSW.

PREVIOUS VALID DISCUSSION...

UPPER LEVEL LOW PRESSURE REMAINS OVER THE VIRGINIA PIEDMONT THIS
MORNING WITH WEAK SFC LOW UNDERNEATH IT. SHOWERS CONTINUE TO STAY
WIDELY SCATTERED AND LIGHT FROM THE SOUTHERN SHENANDOAH VALLEY
SOUTHEAST INTO SOUTHSIDE VIRGINIA.

THE 00Z MODELS ARE SIMILAR IN TAKING THE UPPER VORT/LOW NORTH TOWARD
THE DC AREA THIS AFTERNOON AND WEAKENING WHILE KEEPING SOME LOW LVL
CONVERGENCE AND SHOWER THREAT ACROSS THE NRN CWA. LEANING TOWARD
CHANCE POPS FROM THE GREENBRIER VALLEY EAST INTO OUR NRN VIRGINIA
COUNTIES...NORTH OF THE JAMES RIVER...WITH ISOLATED COVERAGE FURTHER
SOUTH AND ALONG THE BLUE RIDGE. THE NRN CWA LOOKS TO HOLD ONTO MORE
CLOUDS THROUGH THE DAY WHILE ENOUGH SUN ELSEWHERE SHOULD SEND TEMPS
A BIT WARMER THAN WHAT OCCURRED SATURDAY. WENT CLOSE TO THE LOCAL
MOS WITH LOWER 80S SOUTHEAST AND FAR SW...WITH MID TO UPPER 70S
ELSEWHERE OUTSIDE THE HIGHER ELEVATIONS.

TONIGHT...THE UPPER TROUGH/VORT CONTINUES TO WEAKEN AND SHIFT ENE
OVER THE DELMARVA. WITH LOSS OF HEATING...DO NOT FORESEE SHOWERS
LASTING MUCH PAST LATE EVENING. THE FORECAST CONCERN OVERNIGHT WILL
BE LOW LVL MOISTURE AS THE NAM KEEPS CLOUDINESS LOCKED IN ALONG THE
FOOTHILLS OF VA/NC AND LEANED TOWARD THIS IDEA. FORECAST SOUNDINGS
ARE NOT AS PREVALENT WITH THIS...SO AFTER MIDNIGHT START TO LOWER
SKY COVER MORE. FOG WILL BE AN ISSUE MONDAY MORNING AS SKIES CLEAR.
COULD SEE SOME DENSE FOG AROUND PARTICULARLY ACROSS THE BLUE
RIDGE...THE SHENANDOAH VALLEY...LYH AND GREENBRIER VALLEY. LOW TEMPS
SHOULD RANGE FROM THE MID TO UPPER 50S ACROSS THE MTNS TO LOWER TO
MID 60S EAST.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY/...
AS OF 400 AM EDT SUNDAY...

HIGH PRESSURE TO BE IN CONTROL FOR THE START OF THE WORK
WEEK...1020-1022MB FINGER OF HIGH PRESSURE EXTENDING NORTH ALONG
THE SPINE OF THE APPALACHIANS. UNDER CLEAR SKIES AND LIGHT
WINDS...WILL START MONDAY OFF WITH SOME MORNING FOG...ESP THE
RIVER VALLEYS. FOG WILL THEN GIVE WAY TO PARTLY/MOSTLY SUNNY
SKIES AND WARMING TEMPS GIVEN SUBSIDENCE AND DEVELOPING SW FLOW.
THIS SHOULD PUSH HIGHS INTO THE 80S MOST SPOTS AND CLOSE TO 90 SE.
WEAK RIDGING HANGS ON THRU MUCH OF MONDAY NIGHT AS HEIGHTS ONCE
AGAIN LOWER WITH THE UPSTREAM TROF DIGGING SE TOWARD THE AREA FROM
THE OHIO VALLEY AND GREAT LAKES REGION. PRE-FRONTAL LOBE OF
DEEPER RH FOLDS INTO THE AREA FROM THE NW TUESDAY BUT HINDERED BY
DEEP WESTERLY FLOW AND WARMTH ALOFT. THINK A BAND OF SHRA/TSRA
POSSIBLE NORTH THRU TUE AFTERNOON AND ELSW DURING THE EVENING AS
FRONT SLOWLY MAKES ITS WAY ACROSS THE REGION. PENDING SOLAR
INSOLATION AHEAD OF FRONT...SHOULD BE ANOTHER WARM DAY...AND ESP
IF THERE IS A WESTERLY DOWNSLOPE COMPONENT TO THE WIND...HIGHS
AGAIN INTO THE 80S AND PERHAPS LOW 90S PIEDMONT.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 1210 PM EDT SATURDAY...

UPPER TROF DIGGING INTO THE AREA FROM THE NW WILL DROP A SURFACE
COLD FRONT THRU THE AREA TUESDAY NIGHT AND INTO THE CAROLINAS
WEDNESDAY. RESULTANT SHOWERS/TSRA DROPPING SE THRU THE REGION
TUESDAY EVENING DESPITE ONLY LIMITED MOISTURE AND WESTERLY FLOW.
THIS WELL IN ADVANCE OF MOISTURE ASSOCIATED WITH ISAAC THAT IS
PROGGED TO MAKE LANDFALL ALONG THE NORTHERN GULF COAST. BOUNDARY
LOOKS TO REMAIN CLOSE ENOUGH TO PROMPT ADDED SHRA/TSRA ESPCLY WITH
HEATING OVER THE SOUTH WED AFTERNOON SO CARRYING SOME CHANCE POPS
AS EAST/SE FLOW DEVELOPS NORTH OF THE FRONT.

BEYOND WEDNESDAY...FORECAST AGAIN HIGHLY DEPENDENT UPON THE TRACK OF
THE ISAAC REMNANT AND JUST HOW FAR NORTH TROPICAL MOISTURE CAN MAKE
IT GIVEN RIDGING ACROSS THE MID ATLANTIC. LATEST CONSENSUS OF THE
EARLIER EURO/GFS...AND BASED ON THE TPC TRACK IN WORKING THE SYSTEM
UP WEST OF THE MOUNTAINS INTO THE WEEKEND...SUPPORTS ONLY SCTD SHRA
COVERAGE THU-SAT AS DEEPER SE FLOW DEVELOPS. HOWEVER COULD SEE A
PERIOD OF ONLY ISOLATED SHRA MIDWEEK GIVEN SUBSIDENCE NE OF
ISAAC...PLUS DEEPER MOISTURE TRAPPED SOUTH OF THE FRONT...AND THEN
PINNED TO THE SW LATE IN THE WEEK BY RIDGING TO THE NORTH. FLOW
WEAKENS/FLATTENS QUITE A BIT BY NEXT WEEKEND...WITH THE JET LIFTING
TO THE NORTH...AND RIDGING TO THE SE WHICH COULD STALL THE REMNANT
LOW SOMEWHERE NEAR THE CENTRAL APPALACHIANS. OTRW MAINLY CHANCE POPS
THRU THE END OF THE EXTENDED WITH TEMPS CLOSE TO NORMAL
MIDWEEK...THEN WARMING INTO THE 80S MOST AREAS BY THE WEEKEND.

&&

.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
AS OF 800 AM EDT SUNDAY...

PSEUDO TROPICAL LOW ACROSS THE PIEDMONT OF VIRGINIA THIS MORNING
WILL WEAKEN AS IT SHIFTS SLOWLY NORTH...BECOMING JUST A WEAK
TROUGH BY THIS AFTERNOON. THE -RA/DZ VCNTY OF LYH/ROA MAY LINGER
INTO EARLY AFTERNOON B4 ENDING. AS SUCH...LOW IFR/MVFR CIGS TO
LINGER UNTIL DEMISE OF PRECIP...THEN CLOUD BASES EXPECTED TO LIFT
INTO VFR RANGE.

WEST OF ROA...SKIES GENERALLY CLEAR. SOME SCT-BKN CU EXPECTED TO
DEVELOP OVER THE MTNS THIS AFTERNOON...CLOUD BASES GENERALLY
3-4KFT. ANY CU THAT FORMS SHOULD DISSIPATE AT SUNSET WITH
GENERALLY CLEAR SKIES THIS EVENING AND EARLY TONIGHT. WITH
CLEARING SKIES...COMBINATION OF LIGHT WINDS AND GOOD RADIATIONAL
CONDITIONS TO PERMIT FORMATION OF FOG...ESP THE RIVER VALLEYS WITH
LIFR ANTICIPATED FOR LWB/BCB...AND COULD ALSO BE A PROBLEM AT LYH
AGAIN AS WELL DUE TO RECENT RAINFALL. WOULD NOT BE SURPRISED TO SEE LYH
WITH DENSE FOG MONDAY MORNING.

MORNING FOG MONDAY TO GIVE WAY TO WIDESPREAD VFR MONDAY AFTERNOON.

A COLD FRONT WILL BE CROSSING THROUGH THE REGION ON
TUESDAY...ASSOCIATED WITH SCATTERED SHOWERS AND THUNDERSTORMS. ANY
IMPACT FROM TS ISAAC TO THE LOCAL REGION IS NOT ANTICIPATED UNTIL
THE LATTER HALF OF NEXT WEEK...ALTHOUGH THIS SYSTEM WILL LIKELY
IMPACT AIR TRAFFIC ROUTES TO OUR SOUTH BEFORE THEN.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.

&&

$$
SYNOPSIS...WP
NEAR TERM...JH/WP
SHORT TERM...PM
LONG TERM...JH
AVIATION...PM/WP








AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 638 AM CDT SUN AUG 26 2012

.SHORT TERM...THROUGH TUESDAY
234 AM CDT SUN AUG 26 2012

MAIN FORECAST CONCERN IS WITH THE RAIN CHANCES TODAY.

SURFACE ANALYSIS THIS MORNING SHOWED A WEAK AREA OF LOW PRESSURE
OVER NORTHEAST KANSAS WITH A TROUGH OF LOW PRESSURE EXTENDING
NORTHEAST INTO CENTRAL WISCONSIN. LOCAL AND REGIONAL RADARS WERE
SHOWING SHOWERS OCCURRING ALONG AND AHEAD OF THE TROUGH FROM
NORTHEAST WISCONSIN INTO WESTERN MISSOURI.

THE LAST SHORT WAVE TROUGH ASSOCIATED WITH THE REMAINS OF THE
CENTRAL ROCKIES UPPER LEVEL LOW WAS OVER EASTERN KANSAS THIS
MORNING WITH THE SURFACE LOW. THIS SHORT WAVE TROUGH IS EXPECTED
TO CONTINUE MOVING NORTHEAST TOWARD LOWER MICHIGAN TODAY. THE WEAK
AREA OF LOW PRESSURE AT THE SURFACE SHOULD TRACK SOUTH OF THE AREA
REACHING THE SOUTHERN PORTION OF LAKE MICHIGAN LATE THIS
AFTERNOON. AS THE LOW AND SHORT WAVE TROUGH PASS BY...THE FORCING
WILL BE EXITING THE AREA WITH THE 26.12Z NAM SHOWING THE WEAK
FRONTOGENESIS ALONG THE TROUGH OF LOW PRESSURE IN THE 1000-850 MB
LAYER SHIFTING EAST OF THE AREA THIS AFTERNOON AND EVENING. THE
WEAK ISENTROPIC UP GLIDE ON THE 310K SURFACE WILL PUSH OFF TO THE
EAST THIS MORNING AS WILL THE BEST MOISTURE TRANSPORT. EXPECT THE
SHOWERS TO CONTINUE MOVING EAST WITH THE BETTER FORCING WITH THE
BEST COVERAGE THIS MORNING OVER THE SOUTHEAST SECTIONS. THE
WESTERN SECTIONS OF THE FORECAST AREA ALREADY LOOK TO BE DONE AND
HAVE REMOVED THE RAIN CHANCES FOR THOSE AREAS. BY AFTERNOON...MOST
OF THE AREA SHOULD BE DRY WITH SOME LINGERING CHANCES ACROSS THE
SOUTHEAST SECTIONS.

HIGH PRESSURE WILL BUILD IN OVER THE AREA TONIGHT ALLOWING THE
SKIES TO CLEAR OUT DURING THE EVENING. THE NAM BUFKIT SOUNDING FOR
KLSE SUGGESTS A STRONG POSSIBILITY OF VALLEY FOG FORMING WITH
LIGHT WINDS UP THROUGH ABOUT 3 THOUSAND FEET AND SATURATION
OCCURRING AT THE SURFACE. IT DOES HAVE A RATHER LARGE TEMP/DEW
POINT SPREAD THIS EVENING BUT THIS SEEMS TO BE BECAUSE IT CREATES
TOO MUCH MIXING THIS AFTERNOON AND LOWERS THE DEW POINT TOO MUCH.
THE 26.04Z RAP SOUNDING DOES NOT SHOW NEARLY AS MUCH MIXING AND
DRYING THIS AFTERNOON SO MORE MOISTURE SHOULD BE IN PLACE THIS
EVENING TO AID IN THE FOG FORMATION. THE HIGH THEN LOOKS TO REMAIN
IN PLACE OVER THE REGION THROUGH TUESDAY WITH MODERATING
TEMPERATURES PUSHING DAYTIME READINGS BACK ABOVE NORMAL.

.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY
234 AM CDT SUN AUG 26 2012

ANY RAIN CHANCES IN THE EXTENDED WILL DEPEND ON THE EVENTUAL PATH
OF TROPICAL STORM ISAAC. THE DIFFERENCES BETWEEN THE 26.00Z GFS
AND 25.12Z ECMWF ARE QUITE LARGE AND WHILE THE GFS NORMALLY DOES A
BETTER JOB OF HANDING TROPICAL SYSTEMS OVER THE OPEN
WATERS...CONFIDENCE ON HOW IT HANDLES THE SYSTEM ONCE IT IS INLAND
IS PRETTY LOW. THE UPPER LEVEL RIDGE IN PLACE AHEAD OF ISAAC
SHOULD REMAIN OVER THE MIDWEST UNTIL LATE IN THE WEEK KEEPING THE
AREA DRY. ALL THE MODELS SUGGEST A NORTHERN STREAM SYSTEM WILL
MOVE ONTO THE PACIFIC NORTHWEST COAST THURSDAY BUT THEN DIFFER ON
HOW FAST THIS MOVES EAST. THE GFS IS THE FASTEST AS IT USES THIS
SYSTEM AS THE KICKER TO RECURVE ISAAC. THE ECMWF IS MUCH SLOWER
WITH THIS SYSTEM AND FARTHER NORTH AS WELL. FOR NOW...PLAN TO
MAINTAIN CONTINUITY WITH THE PREVIOUS FORECAST AND KEEP THE
EXTENDED PERIOD DRY AND WARM.

&&

.AVIATION...TODAY AND TONIGHT
636 AM CDT SUN AUG 26 2012

FOR THIS MORNING...A BAND OF SHOWERS WILL CONTINUE TO MOVE
NORTHEAST ACROSS NORTHEAST IOWA AND SOUTHWEST AND CENTRAL
WISCONSIN. THIS PRECIPITATION HAS PRODUCED IFR TO MVFR CEILINGS
AND MVFR VISIBILITIES. THE CEILINGS MAY BECOME BRIEFLY MVFR AT
KLSE THROUGH 26.15Z. THIS IS COVERED BY A TEMPO GROUP. MEANWHILE
KRST WILL LIKELY CONTINUE TO SEE THEIR CEILING AROUND 4K FEET.

FRO THIS AFTERNOON...THE SKIES WILL GRADUALLY CLEAR. THIS SHOULD
OCCUR AT KRST AROUND 26.20Z AND AT KLSE AROUND 26.22Z.

FOR LATE TONIGHT...AREAS OF VALLEY FOG WILL LIKELY DEVELOP.
HOWEVER NOT SURE WHETHER IT WILL GET INTO KLSE. AS A RESULT...JUST
WENT WITH BCFG AFTER 27.08Z.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
234 AM CDT SUN AUG 26 2012

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

&&

$$

SHORT TERM...04
LONG TERM...04
AVIATION...BOYNE








AREA FORECAST DISCUSSION

NWS PUEBLO CO

 245 PM MDT SUN AUG 26 2012

.SHORT TERM...
(TONIGHT AND MONDAY)

AN UPR RIDGE WL REMAIN CENTERED OVR SRN CO AND NRN NM THROUGH MON.
SHOWERS AND THUNDERSTORMS WILL CONTINUE OVR THE HIGHER TERRAIN THRU
THE EVENING HOURS...BUT ARE EXPECTED TO DIE OFF BY MIDNIGHT.  THE NAM
RAP13 AND HRRR SHOW OF A LINE OF CONVECTION DEVELOPING OVR THE
EASTERN CO PLAINS LATER THIS AFTERNOON WHICH MOVES EASTWARD INTO
EARLY EVENING.  SATELLITE AND RADAR ARE SHOWING A LINE OF SOME
CONVECTION ALONG A WEAK BOUNDARY THAT EXTENDS FROM NE CO AND
SOUTHWESTWARD WHICH HAS PRODUCED SOME THUNDERSTORMS IN NERN EL PASO
COUNTY. THE MODELS HAVE THE RIGHT IDEA...BUT NOT SURE HOW FAR
SOUTHWARD THE CONVECTION WL DEVELOP.  WL GO WITH SOME ISOLD POPS OVR
AT LEAST NORTHERN PORTION OF THE SOUTHEAST PLAINS EARLY THIS EVENING.

ON MONDAY THERE WILL STILL BE SOME RESIDUAL MOISTURE UNDER THE RIDGE
OVR THE AREA...AND ISOLD TO SCT SHOWERS AND TSTMS ARE AGAIN EXPECTED
TO DEVELOP OVR THE HYR TRRN.  THE SERN PLAINS SHOULD BE DRY ON
MONDAY. IN GENERAL...HIGH TEMPS SHOULD BE ABOUT 5-10 DEGREE ABOVE
AVERAGE. /28


.LONG TERM...
(MONDAY NIGHT THROUGH SUNDAY)

...HOT AND DRY WEATHER TO CONTINUE THROUGH NEXT WEEK...

NO CHANGES SEEN FOR THE EXTENDED FORECAST. ALL GUIDANCE POINTS TO
A CONTINUATION OF CURRENT CONDITIONS. HIGH PRESSURE CENTERED OVR
S CO WILL BE THE MAIN PLAYER...AND THIS WILL LEAVE THE ERN CO PLAINS
IN A VERY WARM AND GENERALLY DRY PATTERN THRU AT LEAST THE MIDDLE OF
THE WEEK. TEMPS SHOULD TOP OUT IN THE MID 90S...POSSIBLY HIGHER...FOR
A GOOD PORTION OF THE PLAINS BOTH TUE AND WED. POPS LOOK PRETTY LOW
OVER THE PLAINS...AND ONLY SCT STORMS ARE EXPECTED OVR THE MTS FOR
THIS PERIOD.

MAIN QUESTION IS HOW QUICKLY THE UPPER RIDGE BREAKS DOWN. THE ECMWF
MAINTAINS A STRONG UPPER HIGH...AND KEEPS MOST OF THE ACTIVE WX TO
OUR N THRU THE END OF THE WEEK AND EVEN INTO NEXT WEEKEND. THE GFS IS
STILL MORE OPTIMISTIC AND BRINGS AT LEAST A LOW CHANCE OF PRECIP E
OF THE MTS AS A SERIES OF WEAK FRONTAL PUSHES MOVE ACROSS THE AREA
THU AND SAT NEXT WEEK. WILL STICK CLOSER TO PERSISTENCE FOR NOW AND
STAY CLOSE TO THE ENSEMBLE CONSENSUS...WHICH IS CLOSE TO THE OP
ECMWF FORECAST OF DRY AND VERY WARM CONDITIONS. ROSE

&&

.AVIATION...

SOME SHOWERS AND THUNDERSTORMS WILL CONTINUE OVR THE HYR TRRN INTO
THE EVENING BUT IS EXPECTED TO END BEFORE MIDNIGHT.  KALS COULD SEE
SOME TSTMS IN THE VCNTY THRU ABOUT 02Z.  AT KCOS AND KPUB...CHANCES
FOR TSTM LOOK QUITE LOW.  VFR CONDITIONS ARE EXPECTED AT THE TAF
SITE FOR THE NEXT 24 HRS.

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

28/44









AREA FORECAST DISCUSSION

NWS DENVER CO

 248 PM MDT SUN AUG 26 2012

.SHORT TERM...STORMS DEVELOPING ALONG A WIND CONVERGENCE BOUNDARY
SNAKING ACROSS SERN ELBERT...EXTREME NWRN LINCOLN AND SERN
WASHINGTON COUNTIES AS OF 20Z WILL BE THE AREA TO WATCH FOR THE
NEXT FEW HOURS. DEWPOINTS IN THE MID-UPPER 50S EAST OF THIS
BOUNDARY AND IN THE 30S WEST OF THERE. GOOD SOUTHERLY INFLOW
GENERATING A FEW WEAK VORTICITY COUPLETS INDICATED ON RADAR ALONG
THIS CONVERGENCE LINE. LATEST RUC IS INDICATING SFC BASED CAPES IN
THE 1000-1400 J/KG RANGE IN THE MOIST AIR. HOWEVER STRONG MID-
LEVEL STABLE LAYER MAY HINDER THE GROWTH OF STRONG STORMS. FOR
NOW WILL UP POPS ALONG THIS CONVERGENCE BOUNDARY AND EXTEND 20-30
PCT POPS NORTHWARD ACROSS PHILLIPS AND SEDGWICK COUNTIES THRU EARLY
THIS EVENING. MODELS SHOW THIS BOUNDARY AND THE MOIST AIR SHIFTING
EAST OUT OF THE STATE BETWEEN 03-06Z THIS EVENING. ELSEWHERE...
CONVECTION HAS STRUGGLED TO GET GOING IN THE HIGH COUNTRY...NO
DOUBT BECAUSE OF THE STRONG WARMING AND STABILITY AT MID-LEVELS.
SHOULD ANY STORMS MANAGE TO DEVELOP...WOULDN/T EXPECT THEM TO LAST
LONG. LOOKING FOR LOW TEMPERATURES TONIGHT TO BE A FEW DEGREES
WARMER THAN THOSE LAST NIGHT.

ON MONDAY...A 594 DECAMETER UPPER RIDGE POSITIONS SQUARELY OVER
COLORADO. MID-LEVEL MOISTURE OF SUBTROPICAL ORIGIN WILL CONTINUE
TO RIDE NORTH UP THE WEST SIDE OF THE RIDGE AND OVER WESTERN
COLORADO DURING THE DAY. BELIEVE WE/LL SEE A BIT MORE STORM
ACTIVITY IN THE HIGH COUNTRY TOMORROW. EAST OF THE MTNS...STORMS
WILL STRUGGLE TO DEVELOP...ALTHOUGH COULD SEE A FEW HIGH BASED
STORMS DRIFTING OFF THE FRONT RANGE AND OVER THE NEARBY PLAINS
LATE IN THE DAY. FOR NOW WILL KEEP POPS ON THE VERY LOW SIDE IN
THE I-25 URBAN CORRIDOR BUT WILL GO WITH 20-30 PCT POPS IN THE
HIGH COUNTRY. FARTHER OUT ON THE PLAINS WILL KEEP THINGS DRY.
LOOKING FOR ANOTHER DAY OF 90 DEG TEMPERATURES AT LOWER
ELEVATIONS.

.LONG TERM...THE RIDGE OF HIGH PRESSURE WILL REMAIN ANCHORED OVER
COLORADO THROUGH WEDNESDAY. HOTTER TEMPERATURES AND LIMITED
MOISTURE WILL OCCUR THROUGH FIRST HALF OF THE WEEK. THE BEST CHC
OF THUNDERSTORMS WILL BE OVER THE MOUNTAINS EACH AFTERNOON AND
EVENING. THE WINDS ALOFT WILL REMAIN LIGHT. LATE WEDNESDAY INTO
THURSDAY THE RIDGE WILL FLATTEN AND THE FLOW ALOFT BECOME
SOUTHWESTERLY AS AN UPPER TROUGH MOVES ACROSS THE NRN ROCKIES. BY
THURSDAY THE RIDGE WILL HAVE SHIFTED INTO THE CENTRAL
PLAINS/MIDWEST REGION. THERE WILL BE A MODEST INCREASE IN
SUBTROPICAL MOISTURE AS WELL...WITH A LITTLE BETTER CHANCE OF
PRECIPITATION IN THE MOUNTAINS AND A SLIGHT CHANCE SPREADING INTO
THE NORTHEAST PLAINS FRIDAY THROUGH SUNDAY. IT WILL NOT BE AS HOT
AS A COUPLE OF WEAK FRONTAL BOUNDARIES SLIP INTO THE CWFA FROM
THE NORTH...ONE LATE WEDNESDAY/THURSDAY AND ANOTHER SATURDAY.

&&

.AVIATION...VFR CONDITIONS TO CONTINUE THROUGH MONDAY UNDER A
RIDGE OF HIGH PRESSURE. COULD SEE A FEW HIGH BASED MOSTLY DRY AND
GUSTY STOMS MOVING OFF THE FOOTHILLS LATE MONDAY AFTERNOON.
OTHERWISE LIGHT EAST-SOUTHEASTERLY WINDS WILL BECOME SOUTHERLY OR
DRAINAGE OVERNIGHT. A SIMILAR WIND PATTERN IS EXPECTED ON MONDAY.

&&

.HYDROLOGY...NO HEAVY RAIN OR FLASH FLOOD ISSUES ANTICIPATED
DURING THE NEXT 24 HOURS.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...BAKER
LONG TERM....COOPER
AVIATION...BAKER





AREA FORECAST DISCUSSION

NWS LINCOLN IL

 1250 PM CDT SUN AUG 26 2012

.DISCUSSION...
ISSUED 910 AM CDT SUN AUG 26 2012

SHORT-WAVE TROUGH EVIDENT ON WATER VAPOR IMAGERY OVER EASTERN
KANSAS/OKLAHOMA WILL BE THE PRIMARY FOCUSING MECHANISM FOR SHOWERS
AND THUNDERSTORMS TODAY INTO TONIGHT. LEAD WAVE HAS TRIGGERED
SCATTERED SHOWERS ACROSS THE AREA THIS MORNING...HOWEVER THESE
ARE RAPIDLY LIFTING NORTHWARD AND SHOULD CLEAR MUCH OF THE KILX
CWA WITHIN THE NEXT COUPLE OF HOURS. AFTER A BRIEF LULL IN THE
PRECIP...HIGH-RES MODELS SUCH AS THE HRRR DEVELOP ADDITIONAL
CONVECTION ACROSS WEST-CENTRAL ILLINOIS INTO MISSOURI BY MID TO
LATE AFTERNOON. WITH FORECAST SOUNDINGS INDICATING CAPE VALUES OF
1000 TO 1500J/KG...A FEW STRONG STORMS COULD DEVELOP. MAIN THREATS
FROM ANY STORMS LATER TODAY WILL BE GUSTY WINDS AND HEAVY
DOWNPOURS. HAVE ADJUSTED THE FORECAST TO BETTER ACCOUNT FOR
CURRENT TRENDS. HAVE REMOVED THUNDER MENTION DURING THE
MORNING...AND FOCUSED BEST CHANCES FOR CONVECTION THIS AFTERNOON
ALONG/WEST OF I-55. SHOWERS/STORMS WILL THEN SPREAD FURTHER
EASTWARD INTO EAST-CENTRAL ILLINOIS TONIGHT...AS THE UPPER WAVE
AND ASSOCIATED COLD FRONT MOVE ACROSS THE AREA.



&&

.AVIATION...
ISSUED 1250 PM CDT SUN AUG 26 2012

CEILINGS WILL REMAIN IN THE VFR CATEGORY AT THE I-72 TERMINALS
THIS AFTERNOON...WHILE MVFR/IFR CEILINGS PERSIST AT BOTH KPIA AND
KBMI. ONGOING SHOWERS ALONG/WEST OF THE ILLINOIS RIVER WILL CONTINUE
TO IMPACT KPIA INTO EARLY EVENING...WHILE CONVECTIVE DEVELOPMENT
FURTHER EAST STILL REMAINS IN QUESTION. WITH PARTIAL SUNSHINE
ALLOWING FOR MODEST DESTABILIZATION EAST OF THE ILLINOIS
RIVER...IT APPEARS SCATTERED SHOWERS/STORMS WILL DEVELOP THIS
AFTERNOON AND EVENING. DUE TO UNCERTAINTY CONCERNING EXACT AREAL
COVERAGE AND TIMING...HAVE ONLY INCLUDED VCTS AT THE REMAINING
TERMINALS. ANY CONVECTION THAT DEVELOPS WILL TEND TO PUSH EAST AND
SOUTH OF THE TAF SITES LATER THIS EVENING AS A COLD FRONT DROPS
INTO THE REGION. WINDS WILL BECOME LIGHT/VARIABLE IN THE VICINITY
OF THE FRONT...POTENTIALLY LEADING TO IFR CEILINGS AND AREAS OF
FOG AT KPIA AND KBMI AFTER 08Z. FURTHER SOUTH...WILL KEEP CEILINGS
IN THE MVFR CATEGORY THROUGH THE NIGHT. SKIES WILL CLEAR FROM
NORTH TO SOUTH ACROSS THE AREA BY MONDAY MORNING...AS WINDS SWITCH
TO THE NORTH BEHIND THE DEPARTING FRONT.

BARNES
&&

.PREV DISCUSSION...
ISSUED 302 AM CDT SUN AUG 26 2012

07Z SURFACE ANALYSIS INDICATED A 1011 MB LOW NEAR TOPEKA WITH A WARM
FRONT ARCING NORTHEAST NEAR THE IA/MO BORDER. LOW 70S DEWPOINTS
HAD ADVECTED NORTH TO THIS BOUNDARY. AT THE MID LEVELS...00Z U/A
ANALYSIS AND WATER VAPOR IMAGERY SHOWED A SLOW MOVING SHORTWAVE TROUGH
AXIS OVER EASTERN KS. REGIONAL RADAR MOSAICS INDICATED WIDESPREAD
RAIN AND EMBEDDED THUNDER SHIFTING NORTHEAST FROM WESTERN MO INTO
SOUTHERN IA...ASSOCIATED WITH THESE SFC AND UPPER FEATURES.
LOCALLY...BROAD ELEVATED WARM MOIST ADVECTION WAS PRODUCING PLENTY
OF AC BUT NOT MUCH IN THE WAY OF SHOWERS YET. MAIN FORECAST ISSUE IS
RAINFALL TIMING/COVERAGE/AMOUNTS TODAY INTO MONDAY AS THE SYSTEM
SHIFTS ACROSS THE CWA.

SHORT TERM...TODAY THROUGH MONDAY

MOISTURE ADVECTION AHEAD OF THE MID LEVEL TROUGH WILL BRING A
VERY MOIST AIR MASS INTO THE CWA TODAY AND TONIGHT. W/V IMAGERY
SHOWS A MID-LEVEL TROPICAL/PACIFIC MOISTURE PLUME WELL
ENTRAINED INTO THIS SYSTEM...WHILE LLVL FLOW HAS BROUGHT GULF MOISTURE
AND ASSOCIATED 70+ DEWPOINTS NORTH INTO THE MIDWEST. WITH THESE
FACTORS IN PLACE IT IS NOT SURPRISING TO SEE 2.0-2.2 INCH
PRECIPITABLE WATER VALUES ON FORECAST SOUNDINGS AND NUMERICAL
MODEL OUTPUT. SUCH NUMBERS ARE NEAR THE 99TH PERCENTILE FOR LATE
AUGUST...OR 175 PERCENT OF NORMAL. WITH BROAD ISENTROPIC LIFT IN
PLACE...WAVES OF ADDITIONAL FORCING ASSOCIATED WITH 850-500 MB
TROUGHS AND SHORTWAVE ENERGY WILL BRING SEVERAL ROUNDS OF SHOWERS
AND EMBEDDED THUNDERSTORMS TO THE CWA TODAY AND TONIGHT. HIGHEST
QPF VALUES REMAIN FOCUSED ON THE WESTERN HALF OF THE CWA WHERE
LIFT IS MAXIMIZED THIS AFTERNOON AND EVENING. WIDESPREAD HALF TO
ONE INCH AMOUNTS FROM EAST TO WEST NOW LOOK LIKELY BY MONDAY
MORNING. SOME SIGNS THAT TRAINING OF CONVECTION COULD PRODUCE
ISOLATED 2 INCH AMOUNTS ESPECIALLY NEAR THE NW CWA. PRIMARY
SHORTWAVE WEAKENS AS IT CROSSES THE MISSISSIPPI RIVER THIS
EVENING...LEADING TO LIGHTER TOTALS AND LESS COVERAGE SHOWERS
OVERNIGHT. 00Z MODELS HAVE CONTINUED THE TREND FROM 12Z OF SLOWING
SYSTEM EXIT TO THE EAST AND WILL KEEP CHANCE POPS FOR THE
SOUTHEAST HALF INTO MONDAY AFTERNOON...THOUGH MOST ORGANIZED RAINS
SHOULD BE DISSIPATING BY THEN. DRIER AIR FILTERING IN ON NORTH
WINDS BRING CLEARING SKIES FROM THE NORTH MONDAY AFTERNOON.

AS FAR AS TEMPERATURES ARE CONCERNED...THICK CLOUD COVER AND
OCCASIONAL RAIN MAY KEEP THE NW CWA IN THE UPPER 70S TODAY...WHILE
THE FAR SE COULD SEE ENOUGH SUN AND DRY HOURS TO GET INTO THE UPPER
80S. MONDAY...SUNNIER LOCATIONS IN THE NORTHWEST SHOULD REBOUND
WELL INTO THE UPPER 80S AS COLD ADVECTION IS NON-EXISTENT BEHIND
THE FRONT. CLOUDS LINGERING THROUGH MUCH OF THE AFTERNOON COULD
KEEP PARTS OF THE E/SE IN THE LOWER 80S.

LONG TERM...TUESDAY THROUGH SATURDAY

AN IDEAL STRETCH OF LATE SUMMER WEATHER LOOKS TO SET UP ACROSS THE
AREA FOR MUCH OF THE WEEK...AS SURFACE AND UPPER RIDGING BUILD
OVER THE MIDWEST. THIS WILL PRODUCE MOSTLY CLEAR SKIES...LIGHT
WINDS...AND SEASONABLY LOW HUMIDITY. THIS DRY AIR WILL ALLOW FOR
LARGE DIURNAL TEMPERATURE SWINGS WITH LOWS MAINLY IN THE LOW/MID
60S AND HIGHS IN THE MID 80S TO LOWER 90S. ANY HOPES FOR RAIN WILL
HINGE ON THE EVENTUAL PATH OF ISAAC REMNANTS FOR THE
FRIDAY/SATURDAY TIME FRAME. TO SAY MODEL AGREEMENT IS POOR WOULD BE
AN UNDERSTATEMENT...AND WILL CONTINUE TO KEEP POPS BELOW
MENTIONABLE LEVELS.

25


&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$








AREA FORECAST DISCUSSION

NWS NORTHERN INDIANA

 111 PM EDT SUN AUG 26 2012

.AVIATION...18Z TAFS

BAND OF INITIALLY HIGH BASED SHOWERS ACROSS NE IL...ASSOCIATED
WITH AN AREA OF STRONG MID LVL MOISTURE ADVECTION...SHOULD CLIP
SBN WITH SHOWERS POSSIBLE AT THE TERMINAL BY 19/20Z. MUCH LOWER
CHANCE FOR MORE ISOLATED SHOWER/STORM ACTIVITY AT FWA ALONG THE
LEADING EDGE OF DEEPER MOISTURE AFTER 20/21Z...SO OPTED FOR A
VCTS MENTION HERE. FLIGHT CONDITIONS WILL DETERIORATE TONIGHT INTO
MONDAY MORNING...ESPECIALLY AT SBN...AS DEEPER TROPICAL MOISTURE
OVERSPREADS THE AREA AHEAD OF A SHEARING UPPER LEVEL WAVE AND WEAK
SFC REFLECTION. THE BULK OF THE SHOWER ACTIVITY...AND POSSIBLY
SOME ISO THUNDER...SHOULD ARRIVE THIS EVENING INTO THE EARLY
OVERNIGHT HOURS AT SBN AND LATER TONIGHT AT FWA.

&&

.PREV DISCUSSION... /ISSUED 439 AM EDT SUN AUG 26 2012/

SHORT TERM...TODAY THROUGH MONDAY NIGHT.

TROUGHINESS FROM CLOSED UPPER LOW MOVING TOWARDS HUDSON BAY THIS
MORNING WILL ATTEMPT TO GRAB HOLD OF WEAK BUT MOISTURE LADEN WAVE
CURRENTLY IN SE KANSAS AND PULL IT NE TODAY INTO TONIGHT. LIGHTER
SHOWER ACTIVITY NOTED ACROSS PORTIONS OF WISCONSIN WITH MORE
WIDESPREAD/HEAVIER SHOWERS/STORMS FROM S CNTRL IOWA INTO SW MISSOURI
AND SE KANSAS. NEAR/SHORT TERM MODELS HAVE VARIETY OF SOLUTIONS IN
HANDLING OF THIS ENERGY AND EFFECTS ON THE AREA. PAST SEVERAL RUNS
OF HRRR HAVE SHOWN DEVELOPMENT SHOULD BE UNDERWAY ACROSS WESTERN
ILLINOIS IN AREA LL CONVERGENCE...30 KT LLJ AND PWATS AROUND 2
INCHES. HOWEVER...LITTLE PRECIP NOTED AND NO INDICATIONS OF ANYTHING
IMMINENT. AT THIS POINT...DISCOUNTING (BUT NOT DISCARDING) THIS IDEA
WHICH WOULD BRING IN SHOWERS TO WESTERN AREAS LATER THIS MORNING.
REMAINING MODELS LEAN TOWARDS AWAITING ARRIVAL OF WAVE INTO ILLINOIS
LATER TODAY INTO TONIGHT ALONG A COLD FRONT SET TO MOVE THROUGH
TONIGHT INTO MONDAY. GIVEN BEST DYNAMICS MOVING NORTH OF THE
AREA...WAVE WILL SLOWLY SHEAR OUT AS IT MOVES NORTHEAST.
HOWEVER...GIVEN DEEP MSTR IN PLACE (OVER 2 INCHES FROM OKLAHOMA INTO
SW MISSOURI)...EXPECT CURRENT ACTIVITY TO REMAIN INTACT/EXPAND AS IT
MOVES NORTHEAST. MAJORITY OF MODELS EVENTUALLY FOCUS LLJ INTO
NORTHERN ILLINOIS IN AXIS OF HIGHER PWATS...CAUSING ADDITIONAL
CONVECTION TO BREAK OUT. FROM THIS POINT IS WHERE MODELS DIVERGE
WITH ANYTHING FROM GLANCING BLOW OF SHOWERS IN NW AREAS...TO
WIDESPREAD SHOWERS/EMBEDDED STORMS...TO CONVECTION REMAINING MAINLY
SOUTH OF THE AREA (SOME HINTS OF THIS IN WATER VAPOR WITH GREATEST
MSTR SHIFTING MORE EAST THAN NORTH). DO THINK THAT MOST...IF NOT ALL
AREAS WILL SEE AT LEAST SOME MEASURABLE RAINFALL WITH BASIN AVERAGES
IN THE QUARTER TO HALF INCH RANGE. WITH POTENTIAL FOR MORE CELLULAR
SETUP VS WIDESPREAD AREA OF RAIN/STORMS HAVE OPTED TO CONTINUE WITH
ARRIVAL OF HIGH END CHC POPS NW AREAS LATER THIS
AFTERNOON...EXPANDING TO HIGHER END LIKELY ACROSS MUCH OF THE AREA
BY LATER TONIGHT.

HAVE NUDGED UP POPS SOMEWHAT MONDAY MORNING IN EASTERN AREAS WITH
CONCERNS ABOUT SLOWER DEPARTURE OF ENERGY. IF 3Z SREF WERE TO
VERIFY...SHOWERS/STORMS WOULD REMAIN ACROSS MUCH OF THE AREA THROUGH
MOST OF MONDAY. THIS MODEL IS PRESENTLY AN OUTLIER SO WHILE AT LEAST
CONSIDERED...DISCOUNTED FOR THE TIME BEING WITH DRYING CONDITIONS
FROM NW TO SE THROUGH THE DAY.

TEMPERATURES HAVE SERIOUS BUST POTENTIAL TODAY ACROSS THE AREA. IR
SAT DATA SHOWS CLOUD COVER TO BEGIN TO ARRIVE IN NW AREAS THIS
MORNING AND THEN INCREASING IN COVERAGE/THICKNESS INTO THIS
AFTERNOON. COOLEST HIGHS ARE EXPECTED IN THESE LOCATIONS AS A RESULT
OF THE LIMITED HEATING WITH WARMER TEMPS...CLOSE TO 90 EXPECTED
ACROSS PORTIONS OF NE INDIANA INTO NW OHIO. IF PRECIP DOES INDEED
WAIT UNTIL CLOSER TO THIS EVENING AND HIGH CLOUDS REMAIN THIN
ENOUGH...HIGHS IN THE NW WILL BE TOO COOL AND NEED ADJUSTING. FOR
NOW WILL GENERALLY LEAVE UNTOUCHED. MUGGY NIGHT IN STORE WITH DEWPTS
IN THE UPPER 60S TO AROUND 70 AND LOWS NEAR OR INTO THE 70S MUCH OF
THE NIGHT. ON MONDAY...TEMPS WILL REMAIN AN ISSUE WITH CLEARING
EXPECTED NW WHERE A NICE REBOUND COULD OCCUR GIVEN OVERNIGHT LOWS
ONLY AROUND 70...WITH SE AREAS SLOWER TO CLIMB WITH LINGERING CLOUD
COVER. HAVE KEPT MON/MON NGT LOWS AS IS.

LONG TERM...
TUESDAY THROUGH SATURDAY. FEW CHNGS WRT LONG TERM. CRNT CNTL PLAINS
SHORTWAVE TO MINOR NEWD AS ASSERTIVE MANITOBA MID TROPOSPHERIC
VORTEX SWEEPS INTO JAMES BAY BY ERLY MONDAY. SFC RIDGE IN WAKE TO
BUILD INTO GRTLKS RGN MIDWEEK TO ASSERT DRY/SUBSIDENT AIRMASS
PERSISTING THROUGH LATTER HALF OF WEEK. SHALLOW CAA/925MB THERMAL
TROF AMID FLOW VEERING TO NERLY PEAKS WED AM...THOUGH REBOUND TO
NEAR NORMAL MAX TEMPS ANTICIPATED AMID STRONG INSOLATION AFFORDED BY
DRY AIRMASS/PWAT NEAR 0.50 INCHES. THEREAFTER AIRMASS MODIFIES GRDLY
WARMER NEATH 4 CORNERS RIDGE EXTRUSION NEWD INTO SWRN GRTLKS BY
DY5...THEREAFTER CULMINATING INTO REX BLOCK OF POST TROPICAL
REMNANTS OF ISAAC DY6. WHILE ECMWF HAS UNDERGONE SOME CONSIDERABLE
DEGREE OF VACILLATION IN PRIOR ITERATIONS...FAVOR 26/00 ECMWF WITH
NOTABLE ADHERENCE TO NAM/4KM WRF/OFFICIAL TRACK OF ISAAC IN SHORT
TERM...IN STARK OPPOSITION TO CONFUNDITY OF GFS FAR WRN TRACK INTO
ERN OK. HAVE TEMPERED POPS DY7 SOMEWHAT TOWARD MULTI MODEL BLEND
WITH SLIGHT NUDGE TOWARD LATEST ECMWF IN DEFERENCE TO CONSISTENCY...
PENDING FURTHER ASSESSMENT.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SHORT TERM...FISHER
LONG TERM...MURPHY
AVIATION...STEINWEDEL






AREA FORECAST DISCUSSION

NWS QUAD CITIES IA IL

 1227 PM CDT SUN AUG 26 2012

.AVIATION...
WIDESPREAD RAIN...OCCASIONALLY HEAVY WITH 1/2 TO 1 MILE
VISIBILITIES IN HEAVY RAIN AND FOG...WILL CONTINUE THROUGH 20Z IN
WESTERN SECTIONS OF EASTERN IOWA...NEAR CID...AND DBQ...FARTHER
SOUTHEAST...THIS RAIN EVENT WILL CONTINUE THROUGH 23 TO 00Z THIS
EVENING. CIGS WILL ALSO BE VARIABLE DURING THIS RAIN EVENT...FROM
AROUND 500 FT AGL...TO 2000 FT. SOME BRIEF VFR CIGS ARE ALSO
POSSIBLE...BUT WILL NOT BE EXPLICITLY FORECAST. AFTER RAIN ENDS
TODAY...FROM WEST TO EAST...A WINDOW OF VFR WEATHER FOR A FEW
EVENING HOURS. THEN...AS SKIES CLEAR FROM WEST TO EAST BETWEEN 00Z
AND 03Z...THE MOIST LOW LEVELS STRONGLY SUPPORT DENSE FOG
FORMATION IN ALL AREAS THAT CLEAR OUT. VISIBILITIES ARE FORECAST
FOR LIFR 1/2SM MILE FOR NOW...BUT WILL LIKELY NEED TO BE REFINED
LATER. A SLOW IMPROVEMENT TO MVFR CIGS AND VISIBILITIES IS
FORECAST FOR MONDAY MORNING AFTER 13Z.
ERVIN

&&

.PREV DISCUSSION... /ISSUED 338 AM CDT SUN AUG 26 2012/

SYNOPSIS...
WEAK UPPER LEVEL WESTERLY FLOW CONTINUES OVER NEARLY ALL OF THE
CONUS. CORRESPONDINGLY WEAK 500MB TROUGH SPANS THE PLAINS FROM
SOUTHERN MINNESOTA INTO WEST TEXAS. PLUME OF LOW LEVEL MOISTURE IS
FEEDING FROM THE GULF OF MEXICO INTO THE UPPER MIDWEST...WITH 850MB
DEW POINTS AT OR ABOVE 15C OVER A SIGNIFICANT PORTION OF THE
SOUTHERN PLAINS AND LOWER MS VALLEY. AT THE SURFACE...LOW PRESSURE
IS CENTERED OVER KANSAS CITY THIS MORNING WITH A TROUGH EXTENDING TO
ITS SOUTHWEST...AND THE BEGINNINGS OF A WEAK WARM FRONT DEVELOPING
ACROSS NORTHERN MISSOURI AND SOUTHERN ILLINOIS.

SHORT TERM...TODAY AND TONIGHT...
FIRST WAVE OF SHOWERS ONGOING THIS MORNING OVER NORTHERN PORTIONS OF
THE CWFA...IN A BROAD AREA OF MID LEVEL ISENTROPIC LIFT AROUND
305K.  MAIN SHOW DRIVEN BY THE UPPER TROUGH IS NOW KNOCKING ON OUR
DOOR OVER SOUTHCENTRAL IOWA.  PRECIPITABLE WATERS ABOVE 2
INCHES...ABOUT 175 PERCENT OF NORMAL...OVER THE ENTIRE CWFA THIS
MORNING SUGGEST HIGHLY EFFICIENT RAINFALL PROCESSES. GIVEN THE WEAK
UPPER FLOW...SYSTEM WILL BE SLOW TO PROGRESS...FURTHER PADDING THE
RAINFALL TOTALS.  ALTHOUGH ONSET IS A BIT SLOWER THAN PREVIOUSLY
FORECAST...STILL LOOKS LIKE WE SHOULD SEE WIDESPREAD AMOUNTS NEAR
ONE INCH.  MID LEVEL LAPSE RATES SUGGEST POTENTIAL FOR WIDESPREAD
THUNDER IS LOW.  HOWEVER...ISOLATED EMBEDDED THUNDER HAS CONTINUED
OVERNIGHT OVER NORTHERN MISSOURI AND WILL MAINTAIN MENTION OF
ISOLATED THUNDER AS THE UPPER FORCING MOVES INTO THE AREA THIS
MORNING.

FAVORED THE RAP AND NAM TODAY AS BOTH HAVE A DECENT HANDLE ON THE
SURFACE FEATURES.  BASED ON THE NAM SOLUTION...BROAD SCALE LIFT
CONTINUES THROUGH MOST OF THE DAY AHEAD OF THE SURFACE LOW.  SHOULD
SEE PRECIP ENDING FROM WEST TO EAST LATE TODAY AND INTO TONIGHT AS
THE SYSTEM CLEARS THE AREA.

DMD

LONG TERM...MONDAY THROUGH NEXT SATURDAY...
MAINLY DRY WITH NEAR TO ABOVE NORMAL TEMPS AS SFC AND UPPER RIDGING
DOMINATES FOR MUCH OF THE PERIOD.

MON-WED... DRY AND FEW DEGS COOLER WITH LIGHT NORTHERLY WINDS TO
PERSIST FOR MUCH OF THE PERIOD VEERING TO EASTERLY BY WED AS SFC
HIGH SHIFTS THROUGH GREAT LAKES. H85 THERMAL GRADIENT W-E SHOWN
TO RESIDE OVER CWA WITH H85 TEMPS MAINLY IN RANGE OF 14-18C. THESE
VALUES MIXED TO SFC CLOSER TO DRY ADIABATICALLY SUPPORT WIDESPREAD
80S WITH COOLEST READINGS E/NE AND WARMEST S/SW. LOWS NEAR TO
BELOW COOLEST GUIDANCE WITH GOOD RADIATIONAL COOLING SETUP DURING
THE NIGHTS... WITH 50S FOR LOWS FAIRLY COMMON BOTH TUE AND WED AM.
DRY AIR SHOULD PROMOTE LARGE DIURNAL RANGES ON ORDER OF 30-35+ DEGS.

THU-SAT... UPPER LEVEL RIDGE BUILDS INTO REGION BY LATE WEEK AND THEN
FLATTENS. TEMPS ALOFT WARM WITH H85 TEMPS IN THE RANGE OF 20-25C.
BUT MODELS INDICATE WEAK MIXING REGIME WITH SFC RIDGE AXIS IN CLOSE
PROXIMITY... THUS NOT ABLE TO TAP FULL WARMTH AND SPARING US FROM
BAKING. THEREFORE... CONTINUATION OF MAINLY 80S FOR HIGHS. PCPN CHCS
LATE IN EXTENDED DEPENDENT ON MOVEMENT OF ISAAC REMNANTS.
OVERALL... HAVE SERIOUS DOUBTS THAT WE WILL SEE ANY IMPACT FROM
ISAAC DESPITE LATEST GFS AND GEM SOLUTIONS BRINGING REMNANTS
EITHER UP OVER CWA OR JUST GLANCING S/E CWA. TYPICALLY NEED LANDFALL
TO OCCUR IN TX OR WRN LA FOR THESE SYSTEMS TO HAVE ANY IMPACT
FOR OUR CWA. AT 06Z... GFS AND GEM WERE AROUND 3 MB TOO WEAK WITH
ISAAC AND THIS COULD AT LEAST PARTIALLY EXPLAIN THEIR MORE WESTERN
TRACK. IF WE SEE CONTINUED STRENGTHENING TDY TO HURRICANE THEN WOULD
EXPECT ISAAC TO START CURVING... AND IT WOULD SEEM VERY LIKELY THAT
ISAAC WOULD CONNECT WITH EASTERN TROUGH AND GET PULLED NORTHWARD.
THE KEY WILL BE AMOUNT/RATE OF INTENSIFICATION AS THE SLOWER ISAAC
TAKES TO RAMP UP THE MORE AND MORE A WESTERN TRACK WOULD BE POSSIBLE.
HAVE FOLLOWED HPC GUIDANCE CLOSELY LATE IN THE EXTENDED AND WILL HAVE
MAINLY DRY FCST FRI-SAT WITH ISAAC REMNANTS STAYING TO OUR E/SE.

MCCLURE

&&

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

$$

ERVIN






AREA FORECAST DISCUSSION

NWS GOODLAND KS

 120 PM MDT SUN AUG 26 2012

.UPDATE...
ISSUED AT 117 PM MDT SUN AUG 26 2012

TEMPERATURES CLIMBING TO NEAR PREVIOUSLY EXPECTED MAXES. SO RAISED
MAXES AREA WIDE.

UPDATE ISSUED AT 919 AM MDT SUN AUG 26 2012

JUST COMPLETED AN UPDATE. MAIN REASON FOR THE EXPIRATION OF THE
DENSE FOG ADVISORY/ENDING OF FOG. THEN ADJUSTED SKY COVER AND
DEWPOINTS BASED ON LATEST DATA AND TRENDS. ALSO UPDATED WINDS
THROUGH TOMORROW BASED ON LATEST TRENDS AND NAM DOING VERY WELL AT
THIS TIME. TODAYS LOOK CLOSE/IN GOOD SHAPE AND DID NOT MAKE ANY
ADJUSTMENTS. PRECIPITATION FORECAST FOR LATER THIS AFTERNOON AND
THIS EVENING ALSO LOOKS FINE.

UPDATE ISSUED AT 540 AM MDT SUN AUG 26 2012

UPDATE SENT TO INCLUDE GRAHAM...NORTON AND DECATUR COUNTIES TO THE
DENSE FOG ADVISORY.

UPDATE ISSUED AT 500 AM MDT SUN AUG 26 2012

HAVE ISSUED A DENSE FOG ADVISORY FOR HITCHCOCK AND RED WILLOW
COUNTIES THROUGH 9 AM MDT (10 AM CDT). VISIBILITIES AT KMCK 1/4
MILE OR LESS. LATEST RUC HAS A GOOD HANDLE ON THIS AND WITH LIGHT
WINDS EXPECT THE FOG TO DRIFT INTO HITCHCOCK COUNTY WITHIN THE
NEXT FEW HOURS. WILL HAVE TO WATCH THE ATWOOD AND OBERLIN AREAS
FOR POSSIBLE HEADLINE GIVEN SIMILAR CONDITIONS. WILL WAIT FOR CO-
OP REPORTS AND DAYLIGHT TO VIEW WEB CAMS BEFORE MAKING AND FURTHER
ADJUSTMENTS.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 215 AM MDT SUN AUG 26 2012

TODAY-TONIGHT...AT 08Z THIS MORNING STRATUS AND FOG WERE JUST
EAST OF THE FORECAST AREA BUT MOVING TOWARD THE WEST AT 15 MPH.
THIS WOULD PUT IT AS FAR WEST AS MCCOOK TO OBERLIN AND WAKEENEY BY
12Z THIS MORNING. VISIBILITIES ARE IN THE 1/4 MILE RANGE ARE
COMMON PER OBSERVATIONS. WILL CONTINUE TO WATCH JUST HOW FAR WEST
IT GETS AND SHOULD IT REACH THE FORECAST AREA A DENSE FOG ADVISORY
WILL BE NEEDED.

OTHERWISE OTHER CONCERN IS ON TIMING OF A FEW THUNDERSTORMS WHICH
SHOULD REACH THE WESTERN 1/4 OF THE AREA (MAINLY FAR EASTERN
COLORADO) BY LATE IN THE AFTERNOON. THESE APPEAR TO BE DIURNALLY
DRIVEN WITHIN AN AXIS OF 700-300 MOISTURE AND AM THINKING THAT ANY
STORMS THAT DO DEVELOP WILL DISSIPATE SHORTLY AFTER SUNSET. HIGH
TEMPERATURES TODAY UPPER 80S TO LOW 90S. LOWS TONIGHT UPPER 50S TO
LOW 60S.

MONDAY-TUESDAY NIGHT...UPPER RIDGE TO BUILD OVER COLORADO THROUGH
THE PERIOD. BREEZY SOUTH TO SOUTHEAST WINDS EXPECTED DURING THE
DAY WITH HIGH TEMPERATURES IN THE LOW TO MID 90S BOTH DAYS. LOWS
UPPER 50S TO LOW 60S.

.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 215 AM MDT SUN AUG 26 2012

THE H5 RIDGE THAT WILL DEVELOP EARLIER IN THE PERIOD IS EXPECTED
TO PERSIST UNTIL NEAR THE MIDDLE OF THE EXTENDED RANGE PERIOD WHEN
A WEAK FRONTAL ZONE MAY AFFECT THE TRI-STATE REGION. CONDITIONS
WILL BE HOT AND DRY WEDNESDAY AND THURSDAY AS THE H5 RIDGE
GRADUALLY MOVES EAST AS A TROUGH ENTERS THE PACIFIC NORTHWEST.
LATE THURSDAY A FRONTAL BOUNDARY BEGINS TO FORM THROUGH THE UPPER
HIGH PLAINS AND MOVE EAST DURING THE WEEKEND. FROM LOOKING AT THE
PAST FEW DAYS OF MODEL RUNS THIS FEATURE HAS CONSISTENT...BUT ITS
SPATIAL...TEMPORAL ...AND STRENGTH QUALITIES HAVE BEEN ALL OVER
THE MAP. THIS IS LIKELY DUE TO BOTH THE MODEL HANDLING OF THE
TROUGH DIGGING IN TO THE PACIFIC NORTHWEST AND TROPICAL STORM
ISAAC. FOR NOW HAVE INCLUDED MINIMAL SLIGHT CHANCE POPS ON FRIDAY
EVENING FOR THE NORTHWESTERN PART OF THE CWA...WITH DRY CONDITIONS
FORECAST FOR THE REST OF THE PERIOD. TEMPERATURES OVER THE PERIOD
WILL BE WARMER THAN AVERAGE...WITH HIGHS IN THE MID TO LOWER 90S.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1131 AM MDT SUN AUG 26 2012

VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. ISOLATED
THUNDERSTORMS ARE EXPECTED TO DEVELOP LATE THIS AFTERNOON IN
EASTERN COLORADO AND ARE EXPECTED TO STAY WEST OF KGLD. LEE TROUGH
IS EXPECTED TO STRENGTHEN LATER TONIGHT INTO TOMORROW. THIS WILL
CAUSE SOUTHERLY WINDS TO STRENGTHEN AND BECOME GUSTY AFTER THE SUN
COMES UP ON MONDAY.


&&

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

$$

UPDATE...BULLER
SHORT TERM...99
LONG TERM...JJM
AVIATION...BULLER







AREA FORECAST DISCUSSION

NWS GOODLAND KS

 1133 AM MDT SUN AUG 26 2012

.UPDATE...
ISSUED AT 919 AM MDT SUN AUG 26 2012

JUST COMPLETED AN UPDATE. MAIN REASON FOR THE EXPIRATION OF THE
DENSE FOG ADVISORY/ENDING OF FOG. THEN ADJUSTED SKY COVER AND
DEWPOINTS BASED ON LATEST DATA AND TRENDS. ALSO UPDATED WINDS
THROUGH TOMORROW BASED ON LATEST TRENDS AND NAM DOING VERY WELL AT
THIS TIME. TODAYS LOOK CLOSE/IN GOOD SHAPE AND DID NOT MAKE ANY
ADJUSTMENTS. PRECIPITATION FORECAST FOR LATER THIS AFTERNOON AND
THIS EVENING ALSO LOOKS FINE.

UPDATE ISSUED AT 540 AM MDT SUN AUG 26 2012

UPDATE SENT TO INCLUDE GRAHAM...NORTON AND DECATUR COUNTIES TO THE
DENSE FOG ADVISORY.

UPDATE ISSUED AT 500 AM MDT SUN AUG 26 2012

HAVE ISSUED A DENSE FOG ADVISORY FOR HITCHCOCK AND RED WILLOW
COUNTIES THROUGH 9 AM MDT (10 AM CDT). VISIBILITIES AT KMCK 1/4
MILE OR LESS. LATEST RUC HAS A GOOD HANDLE ON THIS AND WITH LIGHT
WINDS EXPECT THE FOG TO DRIFT INTO HITCHCOCK COUNTY WITHIN THE
NEXT FEW HOURS. WILL HAVE TO WATCH THE ATWOOD AND OBERLIN AREAS
FOR POSSIBLE HEADLINE GIVEN SIMILAR CONDITIONS. WILL WAIT FOR CO-
OP REPORTS AND DAYLIGHT TO VIEW WEB CAMS BEFORE MAKING AND FURTHER
ADJUSTMENTS.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 215 AM MDT SUN AUG 26 2012

TODAY-TONIGHT...AT 08Z THIS MORNING STRATUS AND FOG WERE JUST
EAST OF THE FORECAST AREA BUT MOVING TOWARD THE WEST AT 15 MPH.
THIS WOULD PUT IT AS FAR WEST AS MCCOOK TO OBERLIN AND WAKEENEY BY
12Z THIS MORNING. VISIBILITIES ARE IN THE 1/4 MILE RANGE ARE
COMMON PER OBSERVATIONS. WILL CONTINUE TO WATCH JUST HOW FAR WEST
IT GETS AND SHOULD IT REACH THE FORECAST AREA A DENSE FOG ADVISORY
WILL BE NEEDED.

OTHERWISE OTHER CONCERN IS ON TIMING OF A FEW THUNDERSTORMS WHICH
SHOULD REACH THE WESTERN 1/4 OF THE AREA (MAINLY FAR EASTERN
COLORADO) BY LATE IN THE AFTERNOON. THESE APPEAR TO BE DIURNALLY
DRIVEN WITHIN AN AXIS OF 700-300 MOISTURE AND AM THINKING THAT ANY
STORMS THAT DO DEVELOP WILL DISSIPATE SHORTLY AFTER SUNSET. HIGH
TEMPERATURES TODAY UPPER 80S TO LOW 90S. LOWS TONIGHT UPPER 50S TO
LOW 60S.

MONDAY-TUESDAY NIGHT...UPPER RIDGE TO BUILD OVER COLORADO THROUGH
THE PERIOD. BREEZY SOUTH TO SOUTHEAST WINDS EXPECTED DURING THE
DAY WITH HIGH TEMPERATURES IN THE LOW TO MID 90S BOTH DAYS. LOWS
UPPER 50S TO LOW 60S.

.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 215 AM MDT SUN AUG 26 2012

THE H5 RIDGE THAT WILL DEVELOP EARLIER IN THE PERIOD IS EXPECTED
TO PERSIST UNTIL NEAR THE MIDDLE OF THE EXTENDED RANGE PERIOD WHEN
A WEAK FRONTAL ZONE MAY AFFECT THE TRI-STATE REGION. CONDITIONS
WILL BE HOT AND DRY WEDNESDAY AND THURSDAY AS THE H5 RIDGE
GRADUALLY MOVES EAST AS A TROUGH ENTERS THE PACIFIC NORTHWEST.
LATE THURSDAY A FRONTAL BOUNDARY BEGINS TO FORM THROUGH THE UPPER
HIGH PLAINS AND MOVE EAST DURING THE WEEKEND. FROM LOOKING AT THE
PAST FEW DAYS OF MODEL RUNS THIS FEATURE HAS CONSISTENT...BUT ITS
SPATIAL...TEMPORAL ...AND STRENGTH QUALITIES HAVE BEEN ALL OVER
THE MAP. THIS IS LIKELY DUE TO BOTH THE MODEL HANDLING OF THE
TROUGH DIGGING IN TO THE PACIFIC NORTHWEST AND TROPICAL STORM
ISAAC. FOR NOW HAVE INCLUDED MINIMAL SLIGHT CHANCE POPS ON FRIDAY
EVENING FOR THE NORTHWESTERN PART OF THE CWA...WITH DRY CONDITIONS
FORECAST FOR THE REST OF THE PERIOD. TEMPERATURES OVER THE PERIOD
WILL BE WARMER THAN AVERAGE...WITH HIGHS IN THE MID TO LOWER 90S.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1131 AM MDT SUN AUG 26 2012

VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. ISOLATED
THUNDERSTORMS ARE EXPECTED TO DEVELOP LATE THIS AFTERNOON IN
EASTERN COLORADO AND ARE EXPECTED TO STAY WEST OF KGLD. LEE TROUGH
IS EXPECTED TO STRENGTHEN LATER TONIGHT INTO TOMORROW. THIS WILL
CAUSE SOUTHERLY WINDS TO STRENGTHEN AND BECOME GUSTY AFTER THE SUN
COMES UP ON MONDAY.

&&

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

$$

UPDATE...BULLER
SHORT TERM...99
LONG TERM...JJM
AVIATION...BULLER







AREA FORECAST DISCUSSION

NWS DODGE CITY KS

 1208 PM CDT SUN AUG 26 2012

...UPDATED SYNOPSIS AND AVIATION DISCUSSION...

.SYNOPSIS...
ISSUED AT 1206 PM CDT SUN AUG 26 2012

AT 12Z SUNDAY A 500MB RIDGE EXTENDED FROM NEW MEXICO ACROSS
WESTERN WYOMING AND WESTERN MONTANA INTO ALBERTA CANADA. AN UPPER
LEVEL LOW WAS LOCATED JUST OFF THE COAST OF WASHINGTON AND OREGON.
700MB TEMPERATURES THIS MORNING VARIED FROM 11C AT DODGE CITY TO
15C AT DENVER. THE BETTER 700MB MOISTURE STRETCHED FROM SOUTHERN
IOWA INTO NORTH CENTRAL TEXAS. AT THE SURFACE A COLD FRONT
EXTENDED FROM NORTHERN MISSOURI INTO SOUTHWEST OKLAHOMA. AN AREA
OF HIGH PRESSURE AT 12Z SUNDAY APPEARS CENTERED OVER SOUTHWEST
NEBRASKA.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 336 AM CDT SUN AUG 26 2012

IN THE VERY SHORT TERM...LOW STRATUS AND FOG WILL BE THE MAIN ISSUE
ON THE AVIATION SIDE OF THINGS.  THE GRIDS ALREADY REFLECT
DEVELOPMENT OF CLOUDS AND PATCHY FOG...BUT WILL TRIM BACK THE
WESTERN EDGE OF THIS (ROUGHLY DIGHTON TO DODGE CITY TO COLDWATER
LINE) PER GUIDANCE FROM THE LATEST RUNS OF THE HRRR MODEL AS WELL AS
TRENDS ON SATELLITE.  THE FOG AND STRATUS PROBABLY WONT EVEN MAKE IT
THAT FAR WEST.  THE REST OF THE FORECAST FOR TODAY AND TONIGHT IS
FAIRLY STRAIGHT FORWARD UNDER THE MID LEVEL RIDGE AXIS.  HIGHS TODAY
WILL BE UPPER 80S TO NEAR 90 AS DIRECT INSOLATION WILL PREVAIL.
SURFACE WINDS WILL BEGIN TO RESPOND TO LOWERING PRESSURE OUT WEST
OVER THE HIGHER TERRAIN...BUT MAINLY ACROSS THE WESTERN COUNTIES
CLOSE TO THE COLORADO BORDER (WEST OF HIGHWAY 83). TONIGHT...ANOTHER
CLEAR AND (NEAR) CALM NIGHT IS EXPECTED WITH LOWS IN THE LOWER TO
MID 60S.  A PATCHY AREA OF LIGHT FOG WILL PROBABLY DEVELOP AGAIN IN
LOW LYING AREAS GIVEN IDEAL RADIATIONAL COOLING AND MOIST
GROUND...BUT THE COVERAGE OF ANY FOG DOES NOT REALLY WARRANT
INCLUSION IN GRIDS AT THIS TIME.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 123 AM CDT SUN AUG 26 2012

A RELATIVELY DRY PERIOD IS EXPECTED ACROSS WESTERN KANSAS AS MEDIUM
RANGE MODELS CONTINUE TO INDICATE A LARGE UPPER LEVEL RIDGE OF HIGH
PRESSURE PREVAILING ACROSS THE COLORADO ROCKIES AND THE WESTERN HIGH
PLAINS THROUGH AT LEAST MID WEEK. A GRADUAL WARMING TREND IS LIKELY
THROUGH AT LEAST WEDNESDAY AS A LEE SIDE TROUGH OF LOW PRESSURE
HELPS INFLUENCE A LOW LEVEL SOUTHERLY FLOW ACROSS WESTERN KANSAS
THROUGH MUCH OF THE PERIOD. FOR MONDAY, THE NAM, GFS, AND ECMWF SHOW
H85 TEMPERATURES RANGING FROM JUST ABOVE 20C ACROSS CENTRAL KANSAS
TO JUST ABOVE 25C NEAR THE COLORADO BORDER. ALONG WITH PLENTY OF
SUNSHINE, LOOK FOR HIGHS NEAR TO JUST ABOVE 90F MONDAY AFTERNOON.
THE WARMING TREND WILL CONTINUE WITH HIGHS EXPECTED UP INTO THE LOW
TO MID 90S(F) THROUGH AT LEAST THURSDAY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1206 PM CDT SUN AUG 26 2012

AN AREA OF HIGH PRESSURE AT THE SURFACE WILL SLOWLY MOVE INTO
EASTERN KANSAS OVERNIGHT. LIGHT WINDS WILL PERSIST AND GRADUALLY
BECOME SOUTHEAST AT LESS THAN 10 KNOTS AFTER 00Z MONDAY. CLEAR
SKIES COMBINED WITH LIGHT WINDS MAY ONCE AGAIN GIVE WAY TO SOME
PATCHY FOG TOWARDS DAYBREAK.

&&

.PRELIMINARY POINT TEMPS/POPS...
DDC  88  62  91  62 /   0  10   0   0
GCK  90  61  92  61 /   0  10   0   0
EHA  90  62  92  61 /   0  10   0   0
LBL  88  62  92  62 /   0  10   0   0
HYS  88  63  92  61 /   0  10   0   0
P28  87  66  93  64 /   0  10   0   0

&&

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

$$

SYNOPSIS...BURGERT
SHORT TERM...UMSCHEID
LONG TERM...JJOHNSON
AVIATION...BURGERT







AREA FORECAST DISCUSSION

NWS PADUCAH KY

 1240 PM CDT SUN AUG 26 2012

.UPDATE...
ISSUED AT 1240 PM CDT SUN AUG 26 2012

THE AVIATION SECTION HAS BEEN UPDATED FOR THE 18Z TAF ISSUANCE.

UPDATE ISSUED AT 855 AM CDT SUN AUG 26 2012

JUST UPDATED THE KPAH TAF AND THE PUBLIC FORECAST TO ACCOUNT FOR
SCATTERED SHOWERS ONGOING OVER THE PURCHASE AREA EARLY THIS
MORNING. THE HRRR...06Z NAM AND 00Z WRF RUNS ALL INDICATE AN
UPTICK IN COVERAGE AS THIS ZONE OF SHOWERS PUSHES EASTWARD ACROSS
THE AREA THIS MORNING. TRIED TO INDICATE THIS IN THE POP GRIDS
THROUGH 18Z.

THEY ALSO INDICATE A TREND TOWARD DEVELOPMENT IN THE WEST LATER
THIS AFTERNOON...ESPECIALLY IF THAT AREA CAN WARM UP ANY. TRIED TO
USED THE HRRR AND NAM 2-M TEMPERATURE FORECASTS TO SHOW A
REALISTIC TEMPERATURE TREND THROUGH THE DAY. GIVEN THE AMOUNT OF
CLOUDS OVER THE AREA...AND A FEW CONSPICUOUSLY CLEAR
AREAS...TEMPERATURE TRENDS WILL BE A BEAR TO KEEP UP WITH TODAY.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 313 AM CDT SUN AUG 26 2012

BIGGEST FORECAST CHALLENGE WILL BE WITH RAIN/THUNDER CHANCES...
MAINLY TODAY....AND ESP MON. MID LEVEL TROF AND ASSOCIATED WEAK
SFC SHOULD EVENTUALLY MOVE EAST FROM THE PLAINS AND START TO BRING
SHOWER/THUNDER CHCS TO AREAS ALONG AND WEST OF THE MS RIVER
TODAY/TONIGHT. HOWEVER...IT STILL APPEARS THE BEST CHANCE OF A
MORE WIDESPREAD PRECIP COVERAGE WILL COME ON MONDAY AS THE SFC
FRONT DRIFTS SLOWLY THROUGH THE FORECAST AREA. NOT LOOKING AT A
MAJOR RAIN SYSTEM AT THIS TIME...AND EXTENSIVE CLOUDS SUN NIGHT/MON
WILL LIKELY PRECLUDE ANY SEVERE STORM RISK. RAIN CHANCES WILL
DIMINISH FROM WEST TO EAST MONDAY NIGHT AS THE SFC FRONT EASES
SOUTHEAST AND H70 TROF SHIFTS EAST. THIS SHOULD CREATE A RATHER
DRY TUESDAY. WILL STICK CLOSE TO ONGOING TEMPS....SLIGHTLY ABOVE
NORMAL FOR THIS TIME OF YEAR.

.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 340 AM CDT SAT AUG 25 2012

THE MAIN CONCERN CONTINUES TO BE THE PATH OF TS ISAAC.

THE LATEST MODELS RUNS CONTINUE TO BE IN COMPLETE DISARRAY. THE 12Z
SATURDAY  ECMWF FOR THE FIRST TIME TAKES THE EASTERN MOST PATH ALONG
THE EASTERN COAST. PREVIOUS 3 DAYS IT HAS RANGED FROM WESTERN MO TO
WESTERN KY SO THIS IS THE LARGEST FLIP FLOP FOR THE OPERATIONAL
ECMWF. THE LATEST 00Z SUN ECMWF ACTUALLY BRINGS THE CENTER OF THE
REMNANTS OF ISAAC OVER THE PENNYRILE AREA OF W KY. THE 00Z SUN GFS
RUN ACTUALLY BRINGS THE CENTER OF ISAAC OVER SGF. FOR THE FIRST TIME
THIS WEEK THE GFS HAS THE WESTERN TRACK AND THE ECMWF HAS THE
EASTERN TRACK. THE ENSEMBLES ARE MUCH HELP EITHER. MOST OF THE
MODELS PERFORM WELL UNTIL ISSAC MAKES LANDFALL AND THEN ITS A CRAP
SHOOT AS FAR AS THE MODELS GO. THIS UNCERTAINTY WILL WREAK HAVOC ON
TEMP FCST AS WELL. AS PREVIOUS DISC STATED IT COULD BE 70S WITH
ISSAC OVER THE AREA OR MID 90S IF IT MISSES US. SO AGAIN DRAMATIC
CHANGES SHOULD BE ANTICIPATED WITH THE EXTENDED SHOULD A REASONABLE
SOLUTION REVEAL ITSELF IN THE NEAR FUTURE. FOR NOW WILL LEAN TOWARD
THE NHC FCST AS DID HPC BUT CONFIDENCE IS EXTREMELY LOW.

FOR THE AFOREMENTIONED REASONS LITTLE CHANGE WAS MADE TO TEMPS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1240 PM CDT SUN AUG 26 2012

WILL CONTINUE TO SEE SOME AMOUNT OF CU AND MID CLOUD OVER THE
REGION THROUGH THE PERIOD. THE MVFR CEILING AT KCGI AS OF 17Z
SHOULD NOT LAST LONG BEFORE SCATTERING OUT OR LIFTING ABOVE 3KFT.
SCATTERED SHOWERS MAY FLIRT WITH KOWB FOR THE FIRST FEW HOURS OF
THE FORECAST. DECIDED TO JUST GO WITH A VCSH...AND WILL ADD TS
IF/WHEN IT BECOMES NECESSARY. SOUTH TO SOUTHWEST WINDS MAY GUST
INTO THE TEENS THROUGHOUT THE AREA THIS AFTERNOON. GUIDANCE IS
NOT ALL THAT EXCITED ABOUT CONVECTIVE DEVELOPMENT ELSEWHERE THIS
AFTERNOON...SO WILL HAVE TO AMEND TO HANDLE ANY LATER DEVELOPMENT.

THE COLD FRONT WILL BRING A CHANCE OF SHOWERS AND THUNDERSTORMS TO
THE REGION LATE TONIGHT AND MONDAY MORNING. FOR NOW WILL JUST
MENTION A VCSH AT KCGI GENERALLY AFTER SUNRISE...AND KEEP THE
REMAINDER OF THE AREA DRY. A LIGHT SOUTH WIND TONIGHT WILL VEER TO
WEST OR SOUTHWEST IN THE MORNING. MAY FLIRT WITH SOME MVFR
CEILINGS IN THE MORNING...BUT CONFIDENCE IS NOT HIGH....SO WILL
JUST MENTION A SCATTERED LAYER NEAR 3KFT FOR NOW.

&&

.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&

$$

UPDATE...DRS
SHORT TERM...MEFFERT
LONG TERM....KH
AVIATION...DRS







AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 244 PM EDT SUN AUG 26 2012

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 503 AM EDT SUN AUG 26 2012

SYNOPSIS...WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL
LOW NE OF LAKE WINNIPEG RESULTING IN SW FLOW FROM THE UPPER MS VALLEY
INTO THE NRN GREAT LAKES. AT THE SFC... A COLD FRONT EXTENDED FROM A
TRIPLE POINT WEST OR JAMES BAY SW TO NEAR CYQT/KDLH. -SHRA INTO
CNTRL UPPER MI WERE SUPPORTED BY A WEAK SHRTWV OVER NRN WI IN THE
MOISTURE PLUME REACHING FROM THE SRN PLAINS INTO UPPER MI AND NRN
ONTARIO. ADDITIONAL SHRA WERE ALSO MOVING NE INTO CNTRL WI.
A LINE OF TSRA HAD DEVELOPED AHEAD N OF LAKE SUPERIOR AHEAD OF THE
COLD FRONT ASSOCIATED WITH STRONGER QVECTOR CONV AND HEIGHT FALLS
AHEAD OF THE MID LEVEL TROUGH.

TODAY AND TONIGHT...EXPECT SCT SHRA TO CONTINUE INTO THE CNTRL AND EAST CWA
THIS MORNING...PER RADAR/SATELLITE TRENDS AS ANOTHER WEAK SHORTWAVE
LIFTS TOWARD THE AREA. EVEN THOUGH THICKER CLOUD COVER WILL HOLD TEMPS
DOWN COMPARED TO SATURDAY...EVEN MODEST WARMING AHEAD OF THE FRONT
SHOULD STILL PUSH MAX READINGS TO AROUND 80. WITH THE TEMP
RECOVERY...MUCAPE VALUES MAY ALSO CLIMB INTO THE 500-1000 J/KG RANGE
TO SUPPORT TSRA CHANCES BY LATE THIS MORNING INTO THIS EVENING AS THE
COLD FRONT EDGES THROUGH THE AREA. HOWEVER...SINCE LOW LEVEL CONV AND
FORCING WITH THE FRONT WILL BE RELATIVELY WEAK...THE FCST ONLY
INCLUDES LOWER END CHANCE POPS. ANY REMAINING SHRA/TSRA WILL EXIT THE
ERN CWA AFT 03Z.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 503 AM EDT SUN AUG 26 2012

OVERALL PATTERN FOR THE LONG TERM WILL FEATURE AN UPPER TROUGH
PUSHING INTO THE UPPER GREAT LKS ON SUN NIGHT AND MON BEFORE
SHIFTING E INTO THE NEW ENGLAND STATES. THIS WILL ALLOW AN UPPER
RIDGE TO BUILD OVER THE ROCKIES AND NORTHERN PLAINS WHILE SLOWLY
SHIFTING E INTO THE UPPER MISS VALLEY FOR WED AND THE UPPER GREAT
LKS ON THURS. AT THE SFC...NW FLOW WILL TAKE HOLD FOR MON AHEAD OF
HIGH PRESSURE SLIDING OUT OF THE CANADIAN PRAIRIES AND NORTHERN
PLAINS AND INTO THE UPPER MISS VALLEY. THIS HIGH WILL SLIDE SE OVER
THE UPPER GREAT LAKES REGION FOR MON NIGHT THROUGH WED AND THEN
SLIDE SOUTHEAST INTO THE LOWER GREAT LAKES ON WED NIGHT AND THURS.

MODELS CONSISTENT ON SHORTWAVE MOVING THROUGH ON MON AFTN UNDER THE
NW FLOW ALOFT. H700-500 MOISTURE IS VERY LIMITED...WITH THE BEST
AREA OVER LK SUPERIOR AND ALIGNED WITH STEEPENING LAPSE RATES TO 6.5
C/KM. LOWER MOISTURE IS ALSO LIMITED AND MODELS TRY TO DIMINISH IT
AS IT DROPS SE ACROSS THE CWA. WITH THE MOISTURE AROUND
H850...THINKING IT SHOULD BE ENOUGH FOR AT LEAST SOME DIURNAL CU.
BUT WITH LITTLE TO NO INSTABILITY DUE TO CAPPING INVERSION BETWEEN
H800-600...DON/T EXPECT MUCH MORE THAN THAT. THEREFORE...HAVE BUMPED
THE CLOUDS UP A LITTLE OVER NRN/ERN LK SUPERIOR WHERE THE BETTER MID
LVL MOISTURE IS LOCATED AND ALSO OVER THE LAND AREAS WITH THE
DIURNAL CU.

WITH THE HIGH MOVING IN MON NIGHT...SHOULD BE A DRY PERIOD FOR MUCH
OF THE WORK WEEK. DIURNAL CU POSSIBLE AGAIN ON TUES...BUT THIS TIME
CONFINED TO THE INTERIOR CENTRL AND NEAR LK MI AS THE DRIER AIR FROM
THE HIGH SETTLES IN. UPPER TROUGH SLIDING THROUGH WITH THE CANADIAN
HIGH WILL LEAD TO COOLER TEMPERATURES FOR MON/TUES...WITH HIGHS
MAINLY IN THE 70S. THEN AS THE HIGH SHIFTS SE...SWRLY RETURN FLOW
WILL START TO PUSH TEMPS BACK UP AND ON A BREEZY THURS...HIGHS WILL
APPROACH 90 DEGREES ONCE AGAIN UNDER THE UPPER RIDGE.

THEN FOR FRI/SAT...EXTENDED MODELS AND THEIR ENS MEANS CONSISTENT ON
THE IDEA OF THE UPPER RIDGE FLATTENING OUT DUE TO A SHORTWAVE
PULLING OUT OF THE UPPER TROUGH OVER THE PAC NW. STILL SOME
DIFFERENCES IN THE INTENSITY OF THE WAVE AND THE EXACT TRACK...BUT
THE TIMING OF MOVING FROM OREGON TO NRN ONTARIO ON THURS/FRI IS
CONSISTENT. THIS WOULD LEAD TO A WEAK COLD FRONT MOVING ACROSS THE
AREA ON THURS NIGHT AND FRI. RIGHT NOW...APPEARS TO BE FAIRLY
DRY...SO WILL ONLY MENTION SLIGHT CHANCES OVER THE NW HALF OF LK
SUPERIOR. THINGS REALLY START TO DIFFER ON SAT...AS 00Z GFS WANTS TO
PULL ANOTHER UPPER WAVE ACROSS SRN ONTARIO. 00Z GFS ENS MEAN DOESN/T
FOLLOW THIS IDEA AND STAYS CLOSER TO 12Z ECMWF DETERMINISTIC AND ENS
MEAN ON WRLY FLOW. THUS...WILL FOLLOW THAT IDEA AND KEEP MUCH OF THE
AREA DRY AND CONTINUE THE ABOVE NORMAL TEMPS WITH HIGHS IN THE UPPER
70S AND LOWER 80S.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 243 PM EDT SUN AUG 26 2012

PLENTY OF CLOUDS OVERHEAD HAVE HELPED REDUCE THE THREAT OF
REDEVELOPMENT AND POSSIBLE TS ACTIVITY NEAR THE WEAKENING COLD FRONT
PUSHING ACROSS THE W HALF OF UPPER MI. OTHER THAN A TEMPORARY MVFR
CEILING AT CMX...EXPECT VFR CEILINGS AND VIS TO REMAIN THROUGH THE
NEXT 24 HOURS. WINDS SHOULD DIMINISH TO AROUND 6KTS OR LESS
OVERNIGHT...BEFORE INCREASING OUT OF THE NW MONDAY...STEADY NEAR
10KTS WITH A FEW SLIGHTLY HIGHER GUSTS.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 503 AM EDT SUN AUG 26 2012

WINDS ARE EXPECTED TO REMAIN BELOW 30KTS THROUGH THE FORECAST PERIOD.
LOW PRES OVER CENTRAL MANITOBA LOW PRESSURE WILL LIFT ACROSS HUDSON
BAY TODAY...AND NORTHERN QUEBEC ON MONDAY. THIS WILL KEEP A TROUGH
ACROSS LAKE SUPERIOR THROUGH SUNDAY NIGHT. HIGH PRESSURE STRETCHING
FROM MANITOBA THE CENTRAL PLAINS MONDAY MORNING WILL SLOWLY BUILD
ACROSS THE UPPER GREAT LAKES THROUGH TUESDAY...BEFORE SINKING TO THE
LOWER GREAT LAKES WEDNESDAY. A LOW WILL SLIDE FROM CENTRAL MANITOBA
TO CENTRAL ONTARIO AND HUDSON BAY BY THURSDAY EVENING...ALLOWING A
TROUGH TO DIP OVER LAKE SUPERIOR.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...JLB
LONG TERM...SRF
AVIATION...KF
MARINE...JLB







AREA FORECAST DISCUSSION

NWS NORTH PLATTE NE

 1239 PM CDT SUN AUG 26 2012

.AVIATION...

VFR CONDITIONS TO PREVAIL ACROSS MUCH OF THE FORECAST REGION THROUGH
THE TAF FORECAST PERIOD.  MODEL GUIDANCE STILL INDICATES THE
POTENTIAL OF THUNDERSTORM DEVELOPMENT ACROSS THE EASTERN PANHANDLE
OF NEBRASKA LATE THIS AFTERNOON/EVENING.  MODEL SOUNDINGS WOULD
SUGGEST HIGH BASED STORMS CAPABLE OF MARGINAL HAIL...AND STRONG
ERRATIC WIND.  OTHERWISE...MODEL GUIDANCE IS HINTING AT A RETURN OF
GROUND FOG AT THE KLBF TERMINAL FROM 27.09Z-27.15Z...FORECAST
CONFIDENCE OF LOW FOG DEVELOPMENT IS LESS THAN 20 PERCENT...SO WILL
LEAVE OUT FOR NOW.

&&


PREV DISCUSSION... /ISSUED 339 AM CDT SUN AUG 26 2012/

SHORT TERM...TODAY THROUGH WEDNESDAY

PRIMARY CONCERNS FOR THE FORECAST ARE THUNDERSTORM CHANCES THIS
AFTERNOON AND EVENING AND AGAIN MONDAY EVENING...AS WELL AS
TEMPERATURES. ALSO KEEPING AN EYE ON FIRE CONCERNS THROUGH THE
FIRST HALF OF THE WEEK.

WATER VAPOR IMAGERY THIS MORNING WAS SHOWING THE UPPER LEVEL
SHORTWAVE TROUGH WHICH PUSHED THE COLD FRONT ACROSS THE FORECAST
AREA ON SATURDAY LOCATED FROM CENTRAL KANSAS INTO WISCONSIN.
THE FRONT HAD STALLED OUT JUST TO THE EAST OF THE FORECAST AREA
AND HAD SINCE WASHED OUT...WITH HIGH PRESSURE NOW CENTERED OVER
WESTERN NEBRASKA. THE DEWPOINT GRADIENT REMAINS...WITH MOIST AIR
OVER EASTERN NEBRASKA /60 DEGREE DEWPOINTS ALONG AND EAST OF A KMCK
TO KBBW TO KONL LINE/...WITH VALUES IN THE 30S OVER THE NORTHERN
PANHANDLE. THUNDERSTORMS WERE ONGOING AHEAD OF THE SYSTEM...INTO
IOWA AND MISSOURI...WHILE STRATUS AND FOG WERE OBSERVED ACROSS
MUCH OF EASTERN NEBRASKA.

ONCE AGAIN LOOKING AT THE LARGE SCALE FLOW...THE UPPER LEVEL RIDGE
WAS CENTERED OVER THE SOUTHERN ROCKY MOUNTAIN RANGE. ALSO OF
NOTE...TROPICAL STORM ISAAC REMAINS A FOCAL POINT WITH THE CENTER
CURRENTLY MOVING OVER CUBA.

THE LOCAL FORECAST AREA IS RIGHT ON THE EDGE OF THE LOW LEVEL
MOISTURE AND FOG THIS MORNING. THE RAP SEEMS TO HAVE A GOOD HANDLE
ON THIS MOISTURE AND SHOWS IT DISSIPATING BY 16Z. WITH THE
PLACEMENT OF THE MOISTURE...AND THAT THE MODELS ARE PUSHING THE
SURFACE LOW INTO THE PANHANDLE TO TIGHTEN THE PRESSURE GRADIENT
AND INCREASE THE WIND...THIS SEEMS LIKE A GOOD SOLUTION AND WILL
FOLLOW THIS LEAD INTO THE FORECAST FOR TODAY. WITH THE EARLY
DISMISSAL OF THE CLOUDS...AND RETURN FLOW...WOULD EXPECT STRONG
WARMING TODAY. TEMPERATURES DO WARM A FEW DEGREES ALOFT FROM WHAT
WAS OBSERVED ON SATURDAY...ALTHOUGH SOUNDINGS ARE INDICATING FULL
MIXING WON/T BE REALIZED. HOWEVER WITH THE EXTRA HOURS OF
SUNSHINE...BELIEVE 90S ARE ATTAINABLE FOR TODAY IN MOST LOCATIONS.

AN UPPER LEVEL SHORTWAVE TROUGH WAS OBSERVED EARLY THIS MORNING
MOVING INTO WYOMING. THIS ENERGY WILL BE THE FOCUS FOR
THUNDERSTORM DEVELOPMENT LATER TODAY. ALTHOUGH THE RETURN FLOW
DOESN/T LOOK PARTICULARLY STRONG UNTIL LATER THIS EVENING...BOTH
THE NAM AND GFS INCREASE PRECIPITABLE WATER TO VALUES OF AN INCH
OR MORE /120 PERCENT OF NORMAL/ OVER THE PANHANDLE /JUST FOR
REFERENCE THE 26.00Z LBF SOUNDING OBSERVED PW OF 0.67...WHILE RAP
HAD 0.43/. EVEN IF THE MOISTURE DOESN/T INCREASE THIS MUCH...THERE
SHOULD BE ENOUGH TO ALLOW FOR ISOLATED THUNDERSTORMS TO DEVELOP
OVER THE PANHANDLE LATER THIS AFTERNOON. SOUNDINGS SHOWING
INVERTED-V PROFILE SO WILL CONTINUE TO SEE THE THREATS FOR STRONG
AND ERRATIC WINDS FROM ANY STORMS...AS WELL AS LOW RAINFALL
AMOUNTS AND A CHANCE FOR SOME STRAY DRY LIGHTNING STRIKES. GOING
EASTWARD...MOISTURE INCREASE ISN/T AS SUBSTANTIAL...AND WITH LARGE
SCALE FORCING BEING LESS...THESE AREAS WILL STAY CAPPED SO WILL
KEEP AREAS EAST OF A LINE FROM NORTH PLATTE TO AINSWORTH DRY.

MONDAY WILL BE A SIMILAR DAY TO SUNDAY...WITH STRONG WARMING
EXPECTED WITH LOTS OF SUNSHINE AND HIGHS IN THE 90S. ALTHOUGH THE
RIDGE WILL BUILD INTO THE PLAINS THROUGH THE DAY...A DECENT
SHORTWAVE TROUGH IS SIGNALED TO PUSH OVER THE RIDGE AND INTO
NEBRASKA IN THE AFTERNOON. THIS SIGNAL WAS BEING PICKED UP BY THE
ECMWF/NAM/GEM-REGIONAL/SREF...AND WITH THE PROPER PLACEMENT OF THE
RIDGE...FELT IT WAS FITTING TO ADD A SLIGHT CHANCE OVER TH
PANHANDLE AND FAR NORTHWEST NEBRASKA.

TUESDAY AND WEDNESDAY SHOULD BE DRY...WITH THE UPPER LEVEL RIDGE
IN PLACE OVER THE HIGH PLAINS AND LOW PRESSURE AT THE SURFACE OFF
TO THE WEST. WINDS WILL BE BREEZY FROM THE SOUTH BOTH
DAYS...HOWEVER ALL MODELS ARE IN AGREEMENT WITH KEEPING MOISTURE
LIMITED...WITH DEWPOINTS IN THE 40S AND 50S. THE LACK OF MOISTURE
ADVECTION LIKELY HAS SOMETHING TO DO WITH TROPICAL STORM ISAAC
/LIKELY HURRICANE ISAAC BY THIS TIME/ TAKING MUCH OF THE AVAILABLE
MOISTURE. TUESDAY LOOKS TO BE THE WARMEST DAY OF THE WEEK...WITH
MID TO UPPER 90S EXPECTED...WITH WIDESPREAD 90S FOR WEDNESDAY AS
WELL.

FIRE WEATHER CONCERNS WILL BE ON THE FOREFRONT MONDAY THROUGH
WEDNESDAY...WITH THE COMBINATION OF THE DRY AIR AND BREEZY WINDS.
ALTHOUGH THE CURRENT FORECAST WOULD KEEP CONDITIONS OUT OF
CRITICAL CRITERIA...THE EXTREME DRYNESS OF THE FUELS COULD CAUSE
THE NEED FOR RED FLAG WARNINGS IF CONDITIONS ARE EXPECTED TO BE
CLOSE.

LONG TERM...THURSDAY THROUGH SATURDAY

THE UPPER LEVEL RIDGE HOLDS STRONG THROUGH THE SECOND HALF OF THE
WEEK. THIS WILL KEEP TEMPERATURES WARM AND ABOVE NORMAL IN THE
90S...WITH LITTLE IF ANY CHANCES FOR RAIN. AS THE RIDGE SHIFTS
EAST...COULD GET PACIFIC MOISTURE TO PUSH INTO THE NORTHERN AND
CENTRAL PLAINS...HOWEVER MODELS ARE NOT INDICATING ANY UPPER LEVEL
SUPPORT FOR ANY SHOWER OR STORM DEVELOPMENT SO KEPT THE FORECAST
DRY. IN TURN...THE STRENGTH OF THE RIDGE WILL LIKELY KEEP ANY
MOISTURE FROM ISAAC WELL EAST OF THE PLAINS. THERE HAS BEEN
CONSIDERABLE DIFFERENCES IN WHERE THE SYSTEM WILL TRACK ONCE
COMING ON-SHORE BUT AGAIN BECAUSE OF THE RIDGE OVER THE
PLAINS...IT WILL PROBABLY MOVE NORTH INTO THE OHIO RIVER VALLEY OR
EVEN ALONG THE EAST COAST.


&&

.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&

$$

SHORT TERM/EXTENDED...BROOKS
AVIATION...JACOBS








AREA FORECAST DISCUSSION

NWS BUFFALO NY

 220 PM EDT SUN AUG 26 2012

.SYNOPSIS...
HIGH PRESSURE WILL BRING ONE LAST VERY WARM DAY TODAY...WITH
INCREASING CLOUDS AND A SLIGHT CHANCE OF SHOWERS IN THE AFTERNOON.
THE CHANCE FOR SHOWERS WILL INCREASE FURTHER ON MONDAY AND MONDAY
NIGHT AS A COLD FRONT CROSSES THE REGION. A RETURN TO SEASONABLY
NORMAL TEMPERATURES AND DRY WEATHER IS EXPECTED FOR THE MIDDLE
PORTION OF THE COMING WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
MINOR CHANGES TO THE GRIDS...OTHERWISE FORECAST REMAINS ON TRACK.
PREVIOUS DISCUSSION FOLLOWS BELOW.

SURFACE HIGH PRESSURE IS CENTERED JUST OFF THE NEW ENGLAND COAST
WITH RIDGING EXTENDING BACK ACROSS NY INTO THE EASTERN OHIO VALLEY
THIS MORNING. ALOFT A CUT OFF LOW IS CYCLONICALLY SPINNING OVER THE
VIRGINIAS WITH SOME CONVECTION ACROSS THE DELMARVA. SATELLITE SHOWS
SOME SLOW SHIFT OF MID LAYER CLOUDS NORTHWARD INTO CENTRAL NY AND
THE INTERIOR SOUTHERN TIER.

LOOK FOR INCREASING CLOUDS THROUGH TODAY AS THE CUTOFF LOW CONTINUES TO
DRIFT NORTH. THE INCREASE IN CLOUD COVER AND SLIGHTLY COOLER
TEMPERATURES ALOFT ADVECTING INTO THE REGION ASSOCIATED WITH THE LOW
SHOULD YIELD COOLER TEMPERATURES...PARTICULARLY ACROSS THE SOUTHERN
TIER WHERE HIGHS SHOULD TOP OUT IN THE MID TO UPPER 70S. AREAS
FARTHER NORTH IN THE NIAGARA FRONTIER WILL LIKELY SEE ENOUGH
SUNSHINE TO CLIMB INTO THE LOW TO MID 80S AND THE WARMEST READINGS
WILL BE FOUND ACROSS THE NORTH COUNTRY WHERE SKIES SHOULD REMAIN
MOSTLY SUNNY THROUGHOUT THE DAY.

INCREASING LOW LEVEL MOISTURE WITH DEWPOINTS CREEPING BACK INTO THE
LOWER 60S AND NOMINAL COOLING ALOFT MAY BE JUST ENOUGH TO TRIGGER A
FEW SHOWERS...MAINLY ACROSS AREAS WEST OF THE GENESEE
VALLEY...HOWEVER GIVEN THE AMOUNT OF LINGERING DRY AIR...WIDESPREAD
CONVECTION IS NOT EXPECTED. THE 07Z RUN OF THE HRRR SHOWS SOME
SHOWERS POSSIBLE AROUND 20Z.

TONIGHT...ANY DIURNAL SHOWERS ACROSS WNY SHOULD END WITH HIGH
PRESSURE REMAINING OVER THE AREA. A COLD FRONT WILL CONTINUE TO
PRESS EAST TOWARD THE FORECAST AREA FROM MICHIGAN. CLOUD COVER WILL
INCREASING TOWARD OVERCAST WITH TEMPERATURES OVERNIGHT FALLING ONLY
INTO THE 60S...ON THE WARM SIDE WITH HIGHER HUMIDITY AROUND. FOG
WILL AGAIN BE LIMITED DUE TO WINDS NOT LOWERING TO CALM OVERNIGHT
AHEAD OF A COLD FRONT JUST TO THE WEST.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
FOCUS IN THE SHORT TERM PERIOD WILL BE ON A COLD FRONTAL PASSAGE ON
MONDAY AND ASSOCIATED RAIN CHANCES. THERE REMAINS SOME TIMING
DIFFERENCES WITH THE GFS A GOOD 6 HOURS FASTER THAN THE NAM. THE
SLOWER NAM SOLUTION HAS SOME SUPPORT FROM THE CANADIAN GEM AND SREF
ENSEMBLE MEAN. WITH A WEAK DECAYING CLOSED LOW OVER THE MID ATLANTIC
LIKELY PROVING TO BE A ROADBLOCK TO UPSTREAM SYSTEMS...HAVE FAVORED
THE SLOWER NAM TIMING. WITH THIS IN MIND THE BULK OF THE AREA WILL
BE RAIN FREE MONDAY MORNING WITH INCREASING CLOUDS.

LATER IN THE DAY MODEST MID LEVEL HEIGHT FALLS AND PVA WILL APPROACH
THE REGION...WITH THE ASSOCIATED COLD FRONT ENTERING WESTERN NY BY
LATE AFTERNOON OR EVENING...THEN SWEEPING ACROSS THE REST OF THE
AREA MONDAY NIGHT. A 70+ KNOT UPPER LEVEL JET WILL ALSO PROVIDE SOME
UPPER LEVEL DIVERGENCE AS THE RIGHT ENTRANCE REGION BECOMES SITUATED
OVER THE LOWER LAKES MONDAY AFTERNOON. SEVERAL DAYS OF SOUTHERLY
FLOW AHEAD OF THIS SYSTEM WILL PROVIDE A DECENT MOISTURE RETURN...
WITH PWAT OF AROUND 1.5 INCHES AND SURFACE DEWPOINTS IN THE MID 60S
ON AVERAGE. WITH THIS MOISTURE AND FORCING COMING INTO PLAY...HAVE
INCREASED POPS TO LIKELY FOR THE FRONTAL PASSAGE. THE TIMING OF THE
MOST WIDESPREAD PRECIP WILL BE LATE AFTERNOON AND EARLY EVENING IN
WESTERN NY...AND MAINLY MONDAY EVENING AND NIGHT FROM THE GENESEE
VALLEY EAST INTO CENTRAL AND NORTHERN NY.

INSTABILITY WILL ONLY BE MARGINAL GIVEN THE VERY WARM TEMPS
ALOFT...WITH SBCAPE OF ONLY 500-1000J/KG. A TALL/SKINNY CAPE PROFILE
AND ADEQUATE MOISTURE SUGGEST POTENTIAL FOR LOCAL HEAVY DOWNPOURS
WITH ANY STORMS THAT FORM. THE WEAK INSTABILITY AND RELATIVELY WEAK
WIND FIELDS WILL KEEP STORMS POORLY ORGANIZED WITH LITTLE POTENTIAL
FOR ANY WIND OR HAIL. MONDAY WILL STILL BE QUITE WARM WITH 850MB
TEMPS OF AROUND +15C. WITH THE EXPECTATION THAT RAIN WILL HOLD OFF
UNTIL THE AFTERNOON...HAVE GONE ABOVE ALL MODEL GUIDANCE WITH HIGHS
IN THE MID 80S IN MANY LOCATIONS...ALONG WITH INCREASED HUMIDITY.

THE COLD FRONT AND ASSOCIATED RAIN WILL BE EAST OF THE CWA BY
DAYBREAK TUESDAY. A SECONDARY COLD FRONT AND ASSOCIATED MID LEVEL
SHORTWAVE WILL DROP INTO THE NORTH COUNTRY DURING THE DAY TUESDAY
AND MAY TOUCH OFF A FEW MORE WIDELY SCATTERED LIGHT SHOWERS. SOME
LIMITED MOISTURE ALONG AND AHEAD OF THIS SECONDARY TROUGH WILL ALSO
PRODUCE SOME DIURNAL CUMULUS...WITH A MIX OF SUN AND CLOUDS IN MANY
LOCATIONS. A SOMEWHAT COOLER AIRMASS WILL BUILD INTO THE AREA WITH
TEMPERATURES DROPPING BACK CLOSER TO AVERAGE. EXPECT HIGHS IN THE
MID TO UPPER 70S IN MOST LOCATIONS.

TUESDAY EVENING THE SECONDARY COLD FRONT WILL DROP SOUTH ACROSS THE
AREA WITH A PERIOD OF CLOUD COVER...FOLLOWED BY CLEARING SKIES
OVERNIGHT AND ADDITIONAL COLD AIR ADVECTION. THIS WILL ALLOW TEMPS
TO DROP INTO THE MID 50S ON THE LAKE PLAINS AND AROUND 50 IN THE
COOLER SOUTHERN TIER VALLEYS AND TUG HILL REGION.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ON WEDNESDAY A LONGWAVE TROUGH WILL BECOME ESTABLISHED ACROSS
SOUTHEAST CANADA WITH A NORTHWEST FLOW OF COOLER AIR DIRECTED INTO
THE GREAT LAKES. SURFACE HIGH PRESSURE WILL BUILD INTO THE OHIO
VALLEY AND GREAT LAKES WITH A RETURN TO SUNSHINE. 850MB TEMPS OF
ONLY AROUND +8C WILL SUPPORT HIGHS IN THE MID 70S ACROSS LOWER
ELEVATIONS AND AROUND 70 ACROSS HIGHER TERRAIN. HIGH PRESSURE
OVERHEAD WEDNESDAY NIGHT WILL PROVIDE CLEAR SKIES AND A SEASONABLY
COOL NIGHT WITH MID 50S ON THE LAKE PLAINS AND A FEW UPPER 40S IN
THE COOLER SOUTHERN TIER VALLEYS AND EAST OF LAKE ONTARIO.

BY THURSDAY AND FRIDAY HIGH PRESSURE WILL BUILD QUICKLY TO THE EAST
COAST AND ALLOW SOUTHWEST RETURN FLOW TO INCREASE. 850MB TEMPS RISE
TO AROUND +14C THURSDAY AFTERNOON ON THE LATEST ECMWF...A LITTLE
WARMER EVEN ON THE GFS. IF THE TIMING HOLDS THIS WILL SUPPORT HIGHS
IN THE LOW TO MID 80S. BY FRIDAY A CENTRAL PLAINS ELEVATED MIXED
LAYER /EML/ PLUME BECOMES CAPTURED BY THE NEXT SYSTEM AND IS
ADVECTED EAST ALL THE WAY INTO THE LOWER LAKES WITH 850MB TEMPS
SOARING TO AROUND +20C. IF THIS VERIFIES...TEMPERATURES WILL MAKE IT
INTO THE 90S ONCE AGAIN WITH HEAT RETURNING. BOTH DAYS WILL BE DRY
AS AN UPPER LEVEL RIDGE SHIFTS EAST ACROSS THE PLAINS AND INTO THE
OHIO VALLEY AND GREAT LAKES.

BY SATURDAY FORECAST UNCERTAINTY INCREASES WITH RESPECT TO THE
TIMING AND PLACEMENT OF THE REMNANTS OF ISAAC. THE LATEST GFS
SPREADS SOME RAIN TOWARDS THE NY/PA BORDER...WHILE THE ECMWF KEEPS
THE SYSTEM CUTOFF AND WELL SOUTH OF THE AREA. PREVIOUS FORECAST HAD
SOME LOW CHANCE POPS AND WILL KEEP THOSE FOR NOW. THE FORECAST FOR
NEXT WEEKEND WILL BE UNCERTAIN FOR SEVERAL DAYS TO COME UNTIL MODEL
GUIDANCE COMES INTO BETTER AGREEMENT WITH THE TRACK OF ISAAC...AND
ITS EVENTUAL INTERACTION WITH THE MID LATITUDE WESTERLIES.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
MOISTURE FROM THE UPPER LOW OVER MD/VA COMBINED WITH DAYTIME HEATING
HAS ALLOWED LOW/MID LEVEL CLOUDS TO DEVELOP AND SPREAD ACROSS
WESTERN NY THIS AFTERNOON. EVEN A FEW SHOWERS HAVE POPPED UP ACROSS
THE REGION, PRIMARILY WEST OF THE GENESEE RIVER VALLEY. AN
ISOLATED -SHRA OR SPRINKLE WILL BE POSSIBLE IN THIS REGION,
ALTHOUGH CHANCES ARE MINIMAL, SO HAVE LEFT THE MENTION OF SHOWER
ACTIVITY OUT OF THE TERMINAL FORECAST. VFR FLIGHT CONDITIONS WILL
LIKELY PREVAIL AT ALL TAF SITES THE REMAINDER OF TODAY.

TONIGHT...ANY LEFT OVER LOW/MID LEVEL CLOUDINESS SHOULD QUICKLY
DISSIPATE WITH THE LOSS OF DAYTIME HEATING AND VFR FLIGHT
CONDITIONS WILL CONTINUE AT ALL TAF LOCATIONS. THE ONLY EXCEPTION WILL BE
KJHW LATE, WHERE THE LOSS OF LOW/MID LEVEL CLOUDS AND HIGHER DEWPOINTS
MAY ALLOW FOG AFTER 07Z TO DEVELOP FOR IFR FLIGHT RULES. HOWEVER...THIS
WILL ALL DEPEND ON HOW MUCH CLOUDINESS IS PRESENT OVERNIGHT.


OUTLOOK...
MONDAY AND MONDAY NIGHT...MVFR WITH SHRA/TSRA LIKELY.
TUESDAY THRU FRIDAY...VFR.

&&

.MARINE...
SOUTHERLY WINDS INCREASING TO 10 TO 15 KNOTS OVER THE LAKES ARE
PRODUCING CHOPPY CONDITIONS. WITH WAVES UP TO THREE FEET TONIGHT
ACROSS EASTERN LAKE ONTARIO. OTHERWISE GOOD BOATING CONDITIONS
EXPECTED ON THE LAKES TODAY.

A COLD FRONT WILL CROSS THE LAKES MONDAY AFTERNOON AND EVENING
BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. WESTERLY WINDS IN
THE WAKE OF THE FRONT WILL LIKELY RESULT IN SMALL CRAFT CONDITIONS
MONDAY AFTERNOON AND MONDAY NIGHT BEFORE HIGH PRESSURE BUILDS BACK
INTO THE REGION TUESDAY.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...SMITH
NEAR TERM...AR/SMITH
SHORT TERM...HITCHCOCK
LONG TERM...HITCHCOCK
AVIATION...AR
MARINE...HITCHCOCK/SMITH








AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

 619 PM EDT SUN AUG 26 2012

.SYNOPSIS...
AN UPPER LOW OVER NORTHWEST VIRGINIA THIS EVENING WILL WEAKEN AS
IT LIFTS SLOWLY TOWARD THE DELMARVA TONIGHT. THIS CIRCULATION
WILL BE ABSORBED INTO A LARGER SCALE TROUGH MOVING EASTWARD FROM
THE GREAT LAKES INTO THE NORTHEAST STATES THROUGH MONDAY NIGHT.
THE GREAT LAKES TROUGH WILL SEND A COLD FRONT ACROSS THE REGION BY
EARLY TUESDAY. HIGH PRESSURE WILL SHIFT SOUTHEAST FROM THE UPPER
MIDWEST INTO PENNSYLVANIA FOR THE MIDDLE OF THE WEEK.

&&

.NEAR TERM /UNTIL 10 PM THIS EVENING/...
THINGS ARE BEGINNING TO QUIET DOWN AFTER A RAPID INCREASE IN
CONVECTIVE ACTIVITY DURING THE MID-LATE AFTN. BULK OF RADAR
RETURNS ARE NOW MAINLY STRATI FORM RAINS SOUTH OF THE LEADING EDGE
GUST FNT SURGING NWD INTO THE N-CNTRL MTNS. 25-35KT GUSTS ARE
STILL POSSIBLE AHEAD OF THE N-NWWD PROPAGATING GUST FRONT...BUT
LIMITED INSTABILITY AND LWR DEWPOINTS SHOULD SPELL AN END TO THIS
ACTIVITY. MODIFIED POPS THRU 03Z TO REFLECT CURRENT PCPN AXIS FM
THV/MDT N-NWWD TO PHILIPSBURG/RENOVO/IPT VCNTY. FF WATCH REMAINS
IN EFFECT UNTL 10 PM...BUT HEAVIEST RNFL IS NOW WELL TO THE SOUTH
OVR THE CHESAPEAKE/DELMARVA REGIONS.

&&

.SHORT TERM /10 PM THIS EVENING THROUGH MONDAY NIGHT/...
EXPECT LOW CLOUDS TO PERSIST TONIGHT ACRS THE CENTRAL MTNS AND
SERN PA. LATEST HRRR SHOWS MUCH OF THE PCPN DISSIPATING BY 03Z.
HOWEVER WILL STILL HANG ONTO HIGH CHC-LOW LKLY POPS THRU 06Z IN
THE EAST.

PESKY MID-UPPER LVL CIRCULATION IN THE MID-ATLC STATES WILL BE
LIFTING NEWD FM THE DELMARVA AT THE START OF THE PD. THIS FEATURE
WILL BE ABSORBED INTO LARGE SCALE TROUGH FCST TO SHIFT SEWD FROM
THE GREAT LAKES INTO THE NORTHEAST.

WEAK RIDGING BTWN THE DEPARTING/WEAKENING UPPER LEVEL CIRCULATION
AND APPROACHING LW TROUGH SHOULD BRING DRIER AND WARMER WX TO
CENTRAL PA BY THE AFTN...WITH ANY SHOWER ACTIVITY ENDING EARLY IN
THE DAY ACROSS THE EASTERN COUNTIES. HOWEVER MAIN QUESTION IS HOW
FAST THE LOW CLOUDS WILL ERODE. WITH THE LLVL FLOW GRADUALLY
VEERING MORE THE WSW...ANTICIPATE A SLOW IMPROVEMENT WITH PEAKS OF
SUN LKLY BY THE AFTN. FOCUS FOR CONVECTION WILL SHIFT TO ELONGATED
SFC COLD FRONT ASSOC WITH THE LG SCALE TROF DIGGING INTO THE NE
STATES. BEST CHC FOR LATE AFTN TSTM WILL BE OVER THE NW MTNS WITH
POPS INCREASING INTO THE CENTRAL ZONES MON NGT.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
THE COLD FRONT WILL PASS TO OUR SOUTH AND EAST LATE MONDAY NIGHT
OR EARLY TUESDAY...TAKING ANY LINGERING SHRA/TSRA WITH IT. SFC
HIGH PRESSURE SHOULD PROVIDE DRY WEATHER AND SEASONABLE TEMPS FOR
WED AND THURS.

A BUILDING RIDGE OF UPPER LEVEL HIGH PRESSURE WILL BEGIN TO WARM
THINGS UP BY FRIDAY. 12Z GEFS PUSHES 850MB TEMPS TO +1 SD BY FRI
AND KEEPS THEM THERE INTO NEXT WEEKEND.

AN ADDITIONAL CONCERN HEADING INTO NEXT WEEKEND IS THE REMNANTS
OF ISAAC. THE 12Z GEFS AND OPERATIONAL GFS BOTH TAKE WHAT IS LEFT
OF ISAAC AND CURL IT UP AND OVER THE BUILDING UPPER LEVEL RIDGE
NEXT WEEKEND....WHICH COULD TURN OUR WEATHER UNSETTLED. THE 12Z
OPERATIONAL ECMWF BRINGS THE REMNANTS OF ISAAC NORTHWARD FROM THE
GULF OF MEX INTO THE OHIO VALLEY BY THIS WEEKEND...WHERE IT
MEANDERS INTO EARLY NEXT WEEK BEFORE BEING EJECTED EASTWARD BY A
DIGGING UPPER LEVEL TROUGH.

&&

.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
GRADUAL IMPROVEMENT/BINOVC CONTINUES ACRS CNTRL PA TERMINALS WITH
MVFR TO VFR CLOUD BASES GENERALLY BTWN 2-4KFT AGL. THIS TREND
WILL CONTINUE INTO THE MID-LATE AFTN AS THE BLYR CONTINUES TO
MIX...BUT EXPECT DIURNAL COOLING/INCREASING STABILITY TO ALLOW
CIGS TO LOWER AND FILL BACK IN OVERNIGHT. TSTM DEVELOPMENT HAS
INCREASED RAPIDLY SOUTH OF THE MASON-DIXON LINE...WITH CLUSTERS/BANDS
LIFTING N-NWWD FROM NRN MD/VA INTO S-CENTRAL PA. THE HIGHEST PROB
OF SHOWERS/ISOLD TSTM WILL EXIST ACRS THE SRN AIRFIELDS. HOWEVER
CONFIDENCE/TIMING ARE STILL UNCERTAIN AND THUS WILL CONTINUE TO
MENTION VCSH IN THE SRN TERMINALS.

OUTLOOK...
MON...AM LOW CIGS -SHRA EAST BCMG MVFR/VFR BY AFTN. PM SHRA/TSRA NW.
MON NGT-TUE...CFRONT PASSAGE. SHRA/TSRA POSS.
WED- THU...MAINLY VFR.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 10 PM EDT THIS EVENING FOR PAZ035-036-
056-057-059-063>066.

&&

$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...EVANEGO
AVIATION...STEINBUGL







AREA FORECAST DISCUSSION

NWS BLACKSBURG VA

 138 PM EDT SUN AUG 26 2012

.SYNOPSIS...
LOW PRESSURE OVER EASTERN VIRGINIA WILL CONTINUE TO DRIFT NORTH
THIS AFTERNOON AND SLOWLY DISSIPATE. WEAK HIGH PRESSURE SHOULD
SLIDE IN BEHIND THE SYSTEM TONIGHT AND MONDAY. A COLD FRONT WILL
DROP IN FROM THE NORTHWEST TUESDAY BEFORE DRIFTING SOUTH INTO THE
CAROLINAS BY MIDWEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 955 AM EDT SUNDAY...

UPPER VORT REMAINS STUCK ACROSS THE NE CORNER OF THE AREA THIS
MORNING...BASICALLY JUST N/NW OF LYH. CLOUD CANOPY WITH THIS
FEATURE AGAIN EXPANDING BACK TO THE SW ALTHOUGH MORNING SOUNDINGS
SHOW THE DEEPER MOISTURE NOW TO THE NE WHERE BETTER INSTABILITY
AND BANDS OF SHRA PERSIST. GUIDANCE SHOWS THIS UPPER FEATURE
GRADUALLY PULLING OUT TO THE NE THIS AFTERNOON ALLOWING CLOUDS TO
DIMINISH AS DRIER AIR SWINGS IN FROM THE NW. HOWEVER STILL APPEARS
ENOUGH LOW LEVEL RH GIVEN HEATING TO PRODUCE ADDITIONAL WIDELY
SCTD BANDS OF SHRA/ISOLD TSRA PENDING OVERALL DEGREE OF HEATING.
THINK BEST CHANCE OF STORMS WILL BE ACROSS THE NW ON THE CURRENT
PERIPHERY OF THE CLOUD AXIS AND CLOSER TO THE VORT CENTER OVER THE
NE IF MORE HEATING DOES DEVELOP. LATEST LOCAL WRF AND THE HRRR DO
HAVE A FEW SHRA ACROSS THE NORTH HALF SO KEEPING SOME SCTD POPS
GOING MAINLY ALONG/NORTH OF HIWAY 460. OTRW WILL RETROGRADE
CLOUDS A BIT MORE TO THE SW INITIALLY THEN HAVE MORE OF A MOSTLY
SUNNY FLAVOR SOUTH TO PC NORTH PER LATEST NAM MOISTURE FIELDS.
TEMPS A BIT MORE TRICKY AS COULD STAY CLOSER TO THE LOW/MID 70S NE
IF CLOUDS LINGER WHILE UPPER 70S/LOW 80S LOOK ON TRACK WITH
MORNING THICKNESS ELSW.

PREVIOUS VALID DISCUSSION...

UPPER LEVEL LOW PRESSURE REMAINS OVER THE VIRGINIA PIEDMONT THIS
MORNING WITH WEAK SFC LOW UNDERNEATH IT. SHOWERS CONTINUE TO STAY
WIDELY SCATTERED AND LIGHT FROM THE SOUTHERN SHENANDOAH VALLEY
SOUTHEAST INTO SOUTHSIDE VIRGINIA.

THE 00Z MODELS ARE SIMILAR IN TAKING THE UPPER VORT/LOW NORTH TOWARD
THE DC AREA THIS AFTERNOON AND WEAKENING WHILE KEEPING SOME LOW LVL
CONVERGENCE AND SHOWER THREAT ACROSS THE NRN CWA. LEANING TOWARD
CHANCE POPS FROM THE GREENBRIER VALLEY EAST INTO OUR NRN VIRGINIA
COUNTIES...NORTH OF THE JAMES RIVER...WITH ISOLATED COVERAGE FURTHER
SOUTH AND ALONG THE BLUE RIDGE. THE NRN CWA LOOKS TO HOLD ONTO MORE
CLOUDS THROUGH THE DAY WHILE ENOUGH SUN ELSEWHERE SHOULD SEND TEMPS
A BIT WARMER THAN WHAT OCCURRED SATURDAY. WENT CLOSE TO THE LOCAL
MOS WITH LOWER 80S SOUTHEAST AND FAR SW...WITH MID TO UPPER 70S
ELSEWHERE OUTSIDE THE HIGHER ELEVATIONS.

TONIGHT...THE UPPER TROUGH/VORT CONTINUES TO WEAKEN AND SHIFT ENE
OVER THE DELMARVA. WITH LOSS OF HEATING...DO NOT FORESEE SHOWERS
LASTING MUCH PAST LATE EVENING. THE FORECAST CONCERN OVERNIGHT WILL
BE LOW LVL MOISTURE AS THE NAM KEEPS CLOUDINESS LOCKED IN ALONG THE
FOOTHILLS OF VA/NC AND LEANED TOWARD THIS IDEA. FORECAST SOUNDINGS
ARE NOT AS PREVALENT WITH THIS...SO AFTER MIDNIGHT START TO LOWER
SKY COVER MORE. FOG WILL BE AN ISSUE MONDAY MORNING AS SKIES CLEAR.
COULD SEE SOME DENSE FOG AROUND PARTICULARLY ACROSS THE BLUE
RIDGE...THE SHENANDOAH VALLEY...LYH AND GREENBRIER VALLEY. LOW TEMPS
SHOULD RANGE FROM THE MID TO UPPER 50S ACROSS THE MTNS TO LOWER TO
MID 60S EAST.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY/...
AS OF 400 AM EDT SUNDAY...

HIGH PRESSURE TO BE IN CONTROL FOR THE START OF THE WORK
WEEK...1020-1022MB FINGER OF HIGH PRESSURE EXTENDING NORTH ALONG
THE SPINE OF THE APPALACHIANS. UNDER CLEAR SKIES AND LIGHT
WINDS...WILL START MONDAY OFF WITH SOME MORNING FOG...ESP THE
RIVER VALLEYS. FOG WILL THEN GIVE WAY TO PARTLY/MOSTLY SUNNY
SKIES AND WARMING TEMPS GIVEN SUBSIDENCE AND DEVELOPING SW FLOW.
THIS SHOULD PUSH HIGHS INTO THE 80S MOST SPOTS AND CLOSE TO 90 SE.
WEAK RIDGING HANGS ON THRU MUCH OF MONDAY NIGHT AS HEIGHTS ONCE
AGAIN LOWER WITH THE UPSTREAM TROF DIGGING SE TOWARD THE AREA FROM
THE OHIO VALLEY AND GREAT LAKES REGION. PRE-FRONTAL LOBE OF
DEEPER RH FOLDS INTO THE AREA FROM THE NW TUESDAY BUT HINDERED BY
DEEP WESTERLY FLOW AND WARMTH ALOFT. THINK A BAND OF SHRA/TSRA
POSSIBLE NORTH THRU TUE AFTERNOON AND ELSW DURING THE EVENING AS
FRONT SLOWLY MAKES ITS WAY ACROSS THE REGION. PENDING SOLAR
INSOLATION AHEAD OF FRONT...SHOULD BE ANOTHER WARM DAY...AND ESP
IF THERE IS A WESTERLY DOWNSLOPE COMPONENT TO THE WIND...HIGHS
AGAIN INTO THE 80S AND PERHAPS LOW 90S PIEDMONT.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 1210 PM EDT SATURDAY...

UPPER TROF DIGGING INTO THE AREA FROM THE NW WILL DROP A SURFACE
COLD FRONT THRU THE AREA TUESDAY NIGHT AND INTO THE CAROLINAS
WEDNESDAY. RESULTANT SHOWERS/TSRA DROPPING SE THRU THE REGION
TUESDAY EVENING DESPITE ONLY LIMITED MOISTURE AND WESTERLY FLOW.
THIS WELL IN ADVANCE OF MOISTURE ASSOCIATED WITH ISAAC THAT IS
PROGGED TO MAKE LANDFALL ALONG THE NORTHERN GULF COAST. BOUNDARY
LOOKS TO REMAIN CLOSE ENOUGH TO PROMPT ADDED SHRA/TSRA ESPCLY WITH
HEATING OVER THE SOUTH WED AFTERNOON SO CARRYING SOME CHANCE POPS
AS EAST/SE FLOW DEVELOPS NORTH OF THE FRONT.

BEYOND WEDNESDAY...FORECAST AGAIN HIGHLY DEPENDENT UPON THE TRACK OF
THE ISAAC REMNANT AND JUST HOW FAR NORTH TROPICAL MOISTURE CAN MAKE
IT GIVEN RIDGING ACROSS THE MID ATLANTIC. LATEST CONSENSUS OF THE
EARLIER EURO/GFS...AND BASED ON THE TPC TRACK IN WORKING THE SYSTEM
UP WEST OF THE MOUNTAINS INTO THE WEEKEND...SUPPORTS ONLY SCTD SHRA
COVERAGE THU-SAT AS DEEPER SE FLOW DEVELOPS. HOWEVER COULD SEE A
PERIOD OF ONLY ISOLATED SHRA MIDWEEK GIVEN SUBSIDENCE NE OF
ISAAC...PLUS DEEPER MOISTURE TRAPPED SOUTH OF THE FRONT...AND THEN
PINNED TO THE SW LATE IN THE WEEK BY RIDGING TO THE NORTH. FLOW
WEAKENS/FLATTENS QUITE A BIT BY NEXT WEEKEND...WITH THE JET LIFTING
TO THE NORTH...AND RIDGING TO THE SE WHICH COULD STALL THE REMNANT
LOW SOMEWHERE NEAR THE CENTRAL APPALACHIANS. OTRW MAINLY CHANCE POPS
THRU THE END OF THE EXTENDED WITH TEMPS CLOSE TO NORMAL
MIDWEEK...THEN WARMING INTO THE 80S MOST AREAS BY THE WEEKEND.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
AS OF 125 PM EDT SUNDAY...

REMNANT UPPER LOW LINGERING ACROSS THE REGION WILL CONTINUE TO
SLOWLY WEAKEN AND SHIFT EAST THIS EVENING AND OVERNIGHT. HOWEVER
PERSISTENT STRATO-CU REMAINS SLOW TO ERODE GIVEN MOISTURE ALOFT
WITH MVFR CIGS LIKELY TO CONTINUE AT TIMES FROM KROA EAST THRU
LATER THIS AFTERNOON AND PERHAPS EARLY THIS EVENING. COULD STILL
SEE -SHRA DEVELOPMENT PROVIDED SOME HEATING BUT SO ISOLATED ONLY
INCLUDING MENTION AT KROA FOR THE MOST PART.

REMAINING CU FIELDS SHOULD DISSIPATE AT SUNSET OVER THE WEST WITH
GENERALLY CLEAR SKIES THIS EVENING AND EARLY TONIGHT. OUT
EAST...BUFKIT SOUNDINGS CONTINUE TO INDICATE SOME CLOUD COVER
LINGERING OR REDEVELOPING OVERNIGHT SO LEFT IN SCATTERED LOW
CLOUDS OUTSIDE OF FOG GIVEN LOW CONFIDENCE. OTRW WITH CLEARING
SKIES...COMBINATION OF LIGHT WINDS AND GOOD RADIATIONAL CONDITIONS
TO PERMIT FORMATION OF FOG AND PERHAPS SPOTTY -DZ...ESPCLY THE RIVER
VALLEYS WITH LIFR/IFR ANTICIPATED FOR KLWB/KBCB...AND COULD ALSO
BE A PROBLEM AT KLYH AGAIN AS WELL DUE TO RECENT RAINFALL.

MORNING FOG/STRATUS MONDAY TO GIVE WAY TO WIDESPREAD VFR MONDAY
AFTERNOON WITH ONLY SOME SCTD CU AND AC AROUND.

A COLD FRONT WILL BE CROSSING THROUGH THE REGION ON TUESDAY
...ASSOCIATED WITH SCATTERED SHOWERS AND THUNDERSTORMS. ANY
IMPACT FROM TS ISAAC TO THE LOCAL REGION IS NOT ANTICIPATED UNTIL
THE LATTER HALF OF NEXT WEEK...ALTHOUGH THIS SYSTEM WILL LIKELY
IMPACT AIR TRAFFIC ROUTES TO OUR SOUTH BEFORE THEN.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.

&&

$$
SYNOPSIS...WP
NEAR TERM...JH/WP
SHORT TERM...PM
LONG TERM...JH
AVIATION...JC/JH/PM/WP







AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 227 PM CDT SUN AUG 26 2012

.SHORT TERM...TONIGHT THROUGH WEDNESDAY
227 PM CDT SUN AUG 26 2012

DRY CONDITIONS EXPECTED THROUGH MID WEEK WITH THE MAIN FORECAST
FOCUS BEING ON TEMPERATURES AND FOG.

CURRENTLY...A SYSTEM THAT BROUGHT RAIN AND CLOUD COVER TO THE
REGION TODAY IS SLOWLY RETREATING EAST INTO THE GREAT LAKES. RAIN
HAS COME TO AN END WITH THE UPPER LEVEL TROUGH PUSHING INTO EASTERN
WISCONSIN. THE QUESTION FOR TONIGHT IS WITH HOW FAST THE CLOUDS
CLEAR OUT AND WHETHER ANY FOG WILL DEVELOP AS IT DID ACROSS
WESTERN MINNESOTA/IOWA THIS MORNING. THE 26.18Z RAP MOISTURE
FIELDS SHOW THE DEEPER MOISTURE FIELD ASSOCIATED WITH THE TROUGH
AND RAINFALL SHIFTING EAST BY THIS EVENING. ALSO...THE STRATUS
FIELD ALONG THE WESTERN SIDE OF THE TROUGH HAS BECOME MUCH MORE
CELLULAR AND SHOULD THIN OUT THIS EVENING AND LEAD TO CLEAR SKIES
THOUGH OUT THE REGION OVERNIGHT.

WITH THESE CLEARING SKIES...LIGHT WINDS...AND A RIDGE AXIS OF
HIGH PRESSURE PUSHING IN...WILL LIKELY SEE SOME FOG FORM ACROSS
THE REGION. THE BEST CHANCES FOR WIDESPREAD AND POSSIBLY DENSE FOG
WILL BE ACROSS SOUTHERN WISCONSIN INTO EASTERN IOWA WHERE THE RAIN
AND CLOUDS HOLD ON LONGER TODAY BEFORE CLEARING OUT LATER TONIGHT.
SHOULD ALSO SEE FOG FORM IN THE MISSISSIPPI AND WISCONSIN RIVER
VALLEYS TONIGHT AS WELL THOUGH HOW WIDESPREAD IT BECOMES WILL BE
DEPENDENT UPON THE LOW LEVEL WIND FIELDS. SEE THE LATEST AVIATION
AFD FOR FURTHER/UPDATED DETAILS ON THE POTENTIAL FOR THIS VALLEY
FOG.

GOING INTO THE EARLY TO MID PORTIONS OF THE WEEK...WARMER AIR WILL
SLOWLY ADVECT INTO THE REGION FROM THE WEST AS A SURFACE RIDGE OF
HIGH PRESSURE SETTLES OVER THE UPPER MISSISSIPPI RIVER VALLEY AND
AN UPPER LEVEL RIDGE BUILDS ACROSS THE ROCKIES. WILL HAVE TO WATCH
A WARM FRONT THAT SURGES NORTHWARD TUESDAY INTO WEDNESDAY AS THE
26.12Z NAM AND GFS TRY TO PRODUCE SOME ELEVATED CONVECTION ACROSS
MINNESOTA WESTERN WISCONSIN. CONFIDENCE IS NOT HIGH THAT THIS
CONVECTION WILL OCCUR GIVEN THE DRY LOW LEVELS AND BETTER MOISTURE
TRANSPORT OFF TO THE WEST...SO HAVE KEPT THE FORECAST DRY THROUGH
THIS PERIOD BUT HAVE PUT SOME SLIGHTLY HIGHER CLOUD COVER IN OVER
THIS TIME FRAME. OTHERWISE EXPECT TEMPERATURES TO SLOWLY REBOUND
GOING INTO MID WEEK AS WARMER AIR SPILLS TO THE EAST AS THE
WESTERN RIDGE BUILDS EASTWARD INTO THE REGION WITH 850MB
TEMPERATURES CLIMBING FROM AROUND +13C ON MONDAY TO AROUND +23C BY
WEDNESDAY.

.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
227 PM CDT SUN AUG 26 2012

THE MAIN STORY FOR THE LATER PART OF THE WEEK WITH WITH THE WARM
AIR MASS THAT WILL TAKE OVER THE UPPER MISSISSIPPI RIVER VALLEY
REGION. AFTER THE WARM FRONT LIFTS NORTH OF THE REGION ON
WEDNESDAY...STRONG SOUTHERLY LOW LEVEL FLOW WILL KICK IN FROM THE
SOUTHERN PLAINS UP INTO THE GREAT LAKES AND NORTHERN PLAINS. THE
BUILDING RIDGE ACROSS THE ROCKIES WILL BEGIN TO SHIFT TO THE EAST
WEDNESDAY NIGHT INTO THURSDAY WITH THURSDAY LOOKING LIKE THE
WARMEST DAY OF THE WEEK. 850MB TEMPERATURE ANOMALIES FROM THE
26.12Z GFS AND ECMWF SHOW THAT THE +23C 850MB TEMPERATURES ARE
ABOUT 2 STANDARD DEVIATIONS ABOVE THE NORM...WHICH WOULD PUSH
RECORD HIGHS IN THE MID 90S. WITH THE WARMER AIR GRADUALLY
GETTING INTO THE REGION...HAVE GONE WITH A GRADUAL WARMING TREND
WITH THE NEAR RECORD HIGHS FOR THURSDAY. PRECIPITATION CHANCES
WILL BE MINIMAL UNTIL MAYBE NEXT WEEKEND AS A COLD FRONT DROPS
DOWN THROUGH LAKE SUPERIOR. THE 26.12Z GFS IS MORE PROGRESSIVE
WITH BRINGING THE FRONT SOUTH THROUGH THE REGION WHILE THE 26.12Z
ECMWF KEEPS THE FRONT TO THE NORTH. THE 26.12Z GFS IS ALSO ON THE
WESTERN TRACK WITH THE REMNANTS OF ISAAC COMING NORTH ALONG THE
MISSISSIPPI WHILE THE 26.12Z KEEPS IT WELL TO THE SOUTHEAST.
CONFIDENCE IS NOT VERY HIGH WITH WHERE THIS FEATURE WILL
TRACK...BUT THERE IS A BETTER CHANCE THAT IT WILL STAY TO THE
SOUTHEAST AND NOT COME INTO THE REGION. THEREFORE...HAVE KEPT THE
FORECAST MAINLY DRY THROUGH NEXT WEEKEND.

&&

.AVIATION...THROUGH 18Z MONDAY
1250 PM CDT SUN AUG 26 2012

MAIN AVIATION CONCERN WILL BE THE POSSIBILITY OF FOG DEVELOPMENT
TONIGHT..SKIES EXPECTED TO CLEAR TONIGHT AS HIGH PRESSURE BUILDS
IN FROM THE PLAINS. PRESSURE GRADIENT IS WEAK THROUGH AND GOOD
AMOUNT OF DECOUPLING IS EXPECTED WITH GENERAL LIGHT NORTHWEST FLOW
AT THE SURFACE. FAIRLY CONFIDENT THAT KRST WILL REMAIN FOG-FREE
TONIGHT WITH LIGHT/GENERALLY DRYING NORTHWEST WINDS. HOWEVER...NOT
AS CONFIDENT WITH THE KLSE TAF. NAM BUFKIT SHOWING TEMP/DEW POINT
SPREAD COLLAPSING IN THE EARLY MORNING HOURS...REACHING NEAR ZERO
BY 10-12Z. THIS WOULD SUGGEST ALMOST CERTAIN FOG. HOWEVER...NORTH-
NORTHWEST WINDS OF 5-10KT EXPECTED AT BLUFF TOP LEVEL. THIS BEING
DOWN-CHANNEL DIRECTION...NOT THINKING THIS IS REALLY CONDUCIVE FOR
WIDESPREAD RIVER VALLEY FOG...ALTHOUGH BELIEVE AT LEAST SOME
VALLEY FOG WILL BE AROUND. FOR NOW...WILL GO WITH BCFG/SCT003 AT
KLSE FROM 08-13Z AND HAVE THE EVENING SHIFT MONITOR CLOSELY.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
227 PM CDT SUN AUG 26 2012

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

&&

$$

SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...DAS