Forecast Discussions mentioning any of "HRRR" "RR" "RUC13" "RUC" received at GSD on 02/08/12

AREA FORECAST DISCUSSION

NWS LINCOLN IL

 252 PM CST MON FEB 6 2012

.DISCUSSION...
ISSUED 252 PM CST MON FEB 6 2012

A LARGE AREA OF STATUS/FOG ACROSS CENTRAL AND SOUTHEAST ILLINOIS
HAS GRADUALLY BEEN ERODING THIS AFTERNOON. THIS CLOUDINESS IS
SANDWICHED BETWEEN A SURFACE RIDGE OF HIGH PRESSURE EXTENDING
ALONG THE OHIO VALLEY AND COLD FRONT SINKING INTO THE GREAT
LAKES/UPPER MIDWEST. MAIN FORECAST CONCERN TODAY REVOLVES AROUND
THE DISPOSITION AND/OR POSSIBLE REFORMATION OF THIS CLOUD DECK
TONIGHT...AS WELL AS PRECIPITATION CHANCES WITH THE APPROACHING
COLD FRONT. THE REMAINDER OF THE FORECAST PERIOD APPEARS RATHER
QUIET AT THE MOMENT...THOUGH A BRIEF COLD SNAP IS STILL EXPECTED
FOR THE WEEKEND.

12Z MODELS STILL IN GOOD AGREEMENT WITH THE BIG PICTURE OVER THE
NEXT FEW DAYS...ALTHOUGH THE SYNOPTIC MODELS REMAIN UNAWARE OF THE
STRATUS/FOG ACROSS THE AREA. THE STRATUS/FOG CONTINUES TO BE
PICKED UP BY SOME MESOSCALE MODELS...BUT THEY ARE NOW OVERPLAYING
THE AREAL EXTENT TO SOME DEGREE. WILL CONTINUE TO HANDLE THE
STRATUS/FOG WITH A COMBINATION OF EXTRAPOLATION AND CONCEPTUAL
MODELS...WITH A MODEL BLEND A GOOD BET OTHERWISE.

SHORT TERM...TONIGHT THROUGH THURSDAY...EXPECT STRATUS/FOG TO
CONTINUE TO ERODE OVER THE NEXT COUPLE OF HOURS UNTIL DIURNAL
HEATING IS LOST. WHAT HAPPENS NEXT IS A BIG QUESTION. WHILE THE
PESKY CLOUD DECK EXPANDED CONSIDERABLY AFTER SUNSET FOR MOST OF
LAST NIGHT DESPITE SHRINKING YESTERDAY...FEEL THIS SHOULD BE LESS
OF A PROBLEM TONIGHT. WEST SOUTHWEST FLOW AHEAD OF THE APPROACHING
FRONT WILL BE STRONGER THAN WAS SEEN LAST NIGHT...HELPING TO KEEP
THE BOUNDARY LAYER MIXED UP A LITTLE BETTER. IN ADDITION...ACROSS
IOWA...WHERE THE CLOUDS WERE MOST PERSISTENT UNDER A SIMILAR WEST
SOUTHWEST FLOW YESTERDAY/LAST NIGHT...THE FLOW WAS COMING OFF A
SNOW FIELD EXTENDING SOUTHWEST INTO NEBRASKA AND KANSAS. WE DO NOT
HAVE THIS POTENTIAL SOURCE OF ADDITIONAL LOW LEVEL MOISTURE
LOCALLY. SO...DO NOT EXPECT TO HIT THE LOW CLOUDS/FOG AS HARD AS
LAST NIGHT. NEVERTHELESS...MID/HIGH LEVEL CLOUDS WILL INCREASE
FROM NORTHWEST TO SOUTHEAST OVERNIGHT AS THE FRONT DRAWS CLOSER.

THE COLD FONT WILL SINK THROUGH THE FORECAST AREA ON TUESDAY...
THOUGH IT IS EXPECTED TO BE MOISTURE STARVED AND A MINIMAL
PRECIPITATION PRODUCER. THE BEST CHANCES FOR PRECIPITATION WILL
OCCUR TUESDAY AFTERNOON/NIGHT ACROSS SOUTHERN SECTIONS OF THE
FORECAST AREA AS AN UPPER LOW OVER THE ROCKIES OPENS UP AND TRACKS
EAST ALONG THE FRONTAL BOUNDARY. FORECAST SOUNDINGS SUGGEST THAT
MOST OF THE PRECIPITATION WILL BE POST FRONTAL WHEN TEMPERATURES
HAVE COOLED SUFFICIENTLY TO FALL AS SNOW. THERE MAY BE A BRIEF
RAIN/SNOW MIX ACROSS SOUTHEAST ILLINOIS. DO NOT EXPECT MUCH MORE
THAN A DUSTING WITH THE SNOW THAT DOES FALL.

SOME FLURRIES MAY LINGER INTO WEDNESDAY...BUT THE WEATHER
WEDNESDAY INTO THURSDAY WILL BE MOSTLY QUIET AS HIGH PRESSURE
BUILDS INTO THE AREA. CHILLY POST FRONTAL TEMPERATURES ON WEDNESDAY
WILL MODERATE A BIT THURSDAY AS RETURN FLOW DEVELOPS ON THE BACK
SIDE OF THE HIGH.

LONG TERM...FRIDAY THROUGH MONDAY...MODELS/ENSEMBLES STILL SUGGEST
SIGNIFICANT UPPER TROFFING AND POOLING OF COLD AIR ACROSS EASTERN
CANADA BY THE END OF THE WEEK. HOWEVER...CONSIDERABLE MODEL SPREAD
AND RUN-TO-RUN VARIABILITY PERSIST WITH THE EXTENT OF COLD AIR
THAT SINKS INTO THE AREA BEHIND A COLD FRONT ON FRIDAY. THIS FRONT
WILL ALSO BE MOISTURE STARVED AND PRODUCE LITTLE IF ANY
PRECIPITATION. DESPITE THE UNCERTAINTY WITH HOW COLD THE WEEKEND
WILL BE...THE MODELS AGREE THAT ANY COLD INTRUSION WILL BE SHORT
LIVED DUE TO A PROGRESSIVE UPPER LEVEL PATTERN. A MODEL CONSENSUS
ALSO EXISTS THAT OUR NEXT WEATHER SYSTEM WILL ARRIVE AROUND
MONDAY...THOUGH AGREEMENT IN THE DETAILS IS NOT VERY GOOD. WILL
ONLY CARRY A LOW CHANCE OF RAIN/SNOW MONDAY UNTIL THE DETAILS CAN
BE IRONED OUT A LITTLE BETTER.

BAK
&&

.AVIATION...
ISSUED 1214 PM CST MON FEB 6 2012
MODELS STILL HAVE NO REFLECTION OF THE LLVL MOISTURE TRAPPED OVER
MUCH OF THE MIDWEST. CONDITIONS IMPROVING...THOUGH SLOWLY. CONCERN
WILL BE SAME AS YESTERDAY...VIS IMPROVING...CIGS REMAIN OR BREAK
ONLY SLIGHTLY WITH THE AFTERNOON HOURS...ONLY TO RETURN AGAIN
TONIGHT. HAVE FOLLOWED THAT TREND...REDUCING CMI AND BMI TO LIFR
AFTER MIDNIGHT...WITH THE DEEPEST MOISTURE AND LEAVING REMAINING
TERMINALS IN THE IFR CAT WITH CIGS. FORECAST IS MORE OF A
PERSISTENCE FORECAST THAN A MODELED ONE...BUT THE HRRR IS THE ONLY
MODEL PICKING UP ON THE TREND...AND IT CONFIRMS THE CONTINUATION
OF THE LLVL RH.

HJS
&&

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

$$











AREA FORECAST DISCUSSION

NWS LINCOLN IL

 1219 PM CST MON FEB 6 2012

.DISCUSSION...
ISSUED 1043 AM CST MON FEB 6 2012
PLENTY OF LLVL MOISTURE TRAPPED NEAR THE SFC RESULTING IN A
CONTINUED LOW CLOUD/LOW VISIBILITY SITUATION FOR MUCH OF CENTRAL
ILLINOIS. PERSISTENT STRATUS SHIELD MOVING IN FROM UPPER MIDWEST
LAST NIGHT WILL BE SLOW TO LEAVE...RESULTING IN A RATHER GRAY DAY.
HAVE UPDATED THE FORECAST TO KNOCK BACK THE TEMPS
CONSIDERABLY...AT LEAST NORTH OF INTERSTATE 70. ALONG AND SOUTH OF
INTERSTATE 70 IS ALREADY SEEING A LITTLE MORE SUNSHINE.
ELSEWHERE...MAX TEMPS NEED TO BE LOWER. HAVE FRESHENED THE GRIDS A
BIT...ISSUE REMAINS WITH THE PERSISTENCE OF THE FOG ADVISORY...AND
HOW QUICKLY THE STRATUS/FOG WILL ERODE WITH MINIMAL DAYTIME
HEATING. WILL BE POSTPONING AN UPDATE TO THE ZONES UNTIL CLOSER TO
NOON.



&&

.AVIATION...
ISSUED 1214 PM CST MON FEB 6 2012
MODELS STILL HAVE NO REFLECTION OF THE LLVL MOISTURE TRAPPED OVER
MUCH OF THE MIDWEST. CONDITIONS IMPROVING...THOUGH SLOWLY. CONCERN
WILL BE SAME AS YESTERDAY...VIS IMPROVING...CIGS REMAIN OR BREAK
ONLY SLIGHTLY WITH THE AFTERNOON HOURS...ONLY TO RETURN AGAIN
TONIGHT. HAVE FOLLOWED THAT TREND...REDUCING CMI AND BMI TO LIFR
AFTER MIDNIGHT...WITH THE DEEPEST MOISTURE AND LEAVING REMAINING
TERMINALS IN THE IFR CAT WITH CIGS. FORECAST IS MORE OF A
PERSISTENCE FORECAST THAN A MODELED ONE...BUT THE HRRR IS THE ONLY
MODEL PICKING UP ON THE TREND...AND IT CONFIRMS THE CONTINUATION
OF THE LLVL RH.

HJS
&&

.PREV DISCUSSION...
ISSUED 235 AM CST MON FEB 6 2012

SHORT TERM...TODAY THROUGH WEDNESDAY...

MAIN HEADACHES THE LAST FEW HOURS HAVE BEEN WITH LOW CLOUDS AND
DENSE FREEZING FOG DEVELOPMENT. STRATUS DECK HAS BEEN ADVANCING
SOUTHEASTWARD AND HAD REACHED THE I-55 CORRIDOR AT 2 AM.
VISIBILITIES ALONG THIS EDGE QUICKLY TANKED AND THE 1/4 MILE
VISIBILITY EXTENDS NORTHWEST FOR ABOUT 60 MILES FROM THE LEADING
EDGE. HAVE ALSO BEEN SEEING SOME PATCHIER DENSE FOG DEVELOPING
OVER THE EASTERN CWA...IN AREAS WHERE SKIES HAVE BEEN MAINLY
CLEAR. MODEL GUIDANCE WITH THIS STRATUS DECK OVER THE LAST DAY OR
TWO HAS BEEN QUITE POOR. THE HRRR APPEARS TO DO THE BEST JOB...BUT
ONLY GOES OUT ABOUT 12 HOURS. THE LATEST RAPID-REFRESH ALSO SEEMS
TO BE OK...AND SPREADS THE CLOUDS OVER MOST OF THE REMAINING CWA
EARLY THIS MORNING AND KEEPS LOWER VISIBILITIES GOING THROUGH
ABOUT 9-10 AM...WITH FOG LIFTING FROM THE NORTHWEST. WILL GO AHEAD
AND ISSUE A DENSE FOG ADVISORY FOR AREAS BETWEEN THE ILLINOIS
RIVER AND I-70 FOR THIS MORNING. TEMPERATURES TODAY WILL BE VERY
TRICKY DEPENDING ON HOW FAST THE CLOUDS FINALLY BREAK UP THIS
AFTERNOON...IF THEY INDEED DO SO. HAVE UNDERCUT GUIDANCE
TEMPERATURES UNDERNEATH BY A FEW DEGREES UNDERNEATH THE STRATUS
DECK...BUT ANY BREAKUP TOO EARLY IN THE DAY WILL CAUSE SIGNIFICANT
ERRORS IN THE HIGH TEMPERATURE FORECAST.

THE OTHER FOCUS DURING THIS PERIOD WILL BE AS A SHORTWAVE...THE
REMNANTS OF A CUTOFF LOW CURRENTLY OVER THE CENTRAL ROCKIES...
INTERACTS WITH ANOTHER WAVE WHICH WILL SWEEP ACROSS THE GREAT
LAKES ON TUESDAY AND WEDNESDAY. STILL NOT A LOT OF MOISTURE
AVAILABILITY WITH THIS SYSTEM...WITH MOST OF THE MODEL GUIDANCE
SUPPORTING LOW CHANCE POPS ACROSS THE SOUTHERN HALF OF THE CWA.
MAY SEE SOME MINOR SNOW ACCUMULATIONS TUESDAY EVENING NEAR THE
I-72 CORRIDOR...DEPENDING ON HOW FAST SURFACE TEMPERATURES DROP
BEFORE THE PRECIPITATION EXITS.

LONG TERM...THURSDAY THROUGH SUNDAY...

MAIN FOCUS IN THIS PERIOD REMAINS WITH ARCTIC AIR MASS WHICH WILL
DROP INTO THE GREAT LAKES LATE IN THE WEEK. COLD FRONT PROGGED TO
MOVE ACROSS THE AREA EARLY FRIDAY MORNING...ALTHOUGH MOST OF THE
MOISTURE WILL BE CLOSER TO THE GREAT LAKES AND WILL GO WITH A DRY
FRONTAL PASSAGE HERE. HOWEVER...LATEST GFS/ECMWF BOTH BRING 850
MB TEMPERATURES AS LOW AS -17C INTO THE CWA BY SATURDAY MORNING...
WHICH WOULD KEEP MUCH OF THE CWA AT OR BELOW FREEZING ON
SATURDAY. AS WITH MOST OF THE COLD PERIODS THIS WINTER...ONLY
LOOKING AT ABOUT A 36-48 HOUR PERIOD WHERE IT WOULD ACTUALLY BE
CONSIDERED TO BE COLD...BEFORE TEMPERATURES QUICKLY RETURN TO NEAR
NORMAL.

GEELHART


&&

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

$$








AREA FORECAST DISCUSSION

NWS LINCOLN IL

 1048 AM CST MON FEB 6 2012

.DISCUSSION...
ISSUED 1043 AM CST MON FEB 6 2012
PLENTY OF LLVL MOISTURE TRAPPED NEAR THE SFC RESULTING IN A
CONTINUED LOW CLOUD/LOW VISIBILITY SITUATION FOR MUCH OF CENTRAL
ILLINOIS. PERSISTENT STRATUS SHIELD MOVING IN FROM UPPER MIDWEST
LAST NIGHT WILL BE SLOW TO LEAVE...RESULTING IN A RATHER GRAY DAY.
HAVE UPDATED THE FORECAST TO KNOCK BACK THE TEMPS
CONSIDERABLY...AT LEAST NORTH OF INTERSTATE 70. ALONG AND SOUTH OF
INTERSTATE 70 IS ALREADY SEEING A LITTLE MORE SUNSHINE.
ELSEWHERE...MAX TEMPS NEED TO BE LOWER. HAVE FRESHENED THE GRIDS A
BIT...ISSUE REMAINS WITH THE PERSISTENCE OF THE FOG ADVISORY...AND
HOW QUICKLY THE STRATUS/FOG WILL ERODE WITH MINIMAL DAYTIME
HEATING. WILL BE POSTPONING AN UPDATE TO THE ZONES UNTIL CLOSER TO
NOON.

HJS
&&

.AVIATION...
ISSUED 515 AM CST MON FEB 6 2012

DURATION OF VLIFR/LIFR CIGS AND VSBYS TODAY THE MAIN FORECAST
CHALLENGE. THE LOW STRATUS DECK THAT WAS OUT TO OUR NORTHWEST
STARTED TO INCREASE ITS SE MOVEMENT LAST EVENING AND HAS PUSHED
TO JUST NORTH OF THE I-70 CORRIDOR...AND EXTENDS WEST THRU THE
NORTHERN HALF OF MO INTO EXTREME EASTERN NEBRASKA. NOT MUCH
HOPE OF SEEING ANY SIGNIFICANT CLEARING TAKING PLACE TODAY
DESPITE BOUNDARY LAYER WINDS INCREASING OUT OF THE WEST AND
SOUTHWEST. WILL TAKE A MORE PESSIMISTIC OUTLOOK WITH RESPECT
TO THE CIGS AND VSBYS TODAY AND CONTINUE TO KEEP AT LEAST IFR
CIGS/VSBYS INTO THIS AFTERNOON. THE BIG QUESTION IS HOW QUICKLY
THAT WILL TRANSITION FROM VLIFR TO IFR. BASED ON THE HI-RES
RAPID REFRESH SOLUTION...WILL START TO SEE A GRADUAL IMPROVEMENT
IN CIGS AND VSBYS AFTR 16Z BUT CONTINUE WITH IFR/LIFR CIGS DURING
THE AFTN. REALLY DON`T SEE ANY MECHANISM TO DISPERSE THE CLOUDS
AND IMPROVE THE CIGS SIGNIFICANTLY UNTIL A COLD FRONT MOVES ACRS
THE AREA LATER TONIGHT OR EARLY TUESDAY MORNING.

SURFACE WINDS WILL TEND TO BACK MORE INTO A SOUTHWEST DIRECTION
TODAY AT 8 TO 13 KTS...AND VEER MORE INTO THE WEST AND THEN
NORTHWEST LATE IN THE FORECAST PERIOD AS THE COLD FRONT
APPROACHES.

SMITH
&&

.PREV DISCUSSION...
ISSUED 235 AM CST MON FEB 6 2012

SHORT TERM...TODAY THROUGH WEDNESDAY...

MAIN HEADACHES THE LAST FEW HOURS HAVE BEEN WITH LOW CLOUDS AND
DENSE FREEZING FOG DEVELOPMENT. STRATUS DECK HAS BEEN ADVANCING
SOUTHEASTWARD AND HAD REACHED THE I-55 CORRIDOR AT 2 AM.
VISIBILITIES ALONG THIS EDGE QUICKLY TANKED AND THE 1/4 MILE
VISIBILITY EXTENDS NORTHWEST FOR ABOUT 60 MILES FROM THE LEADING
EDGE. HAVE ALSO BEEN SEEING SOME PATCHIER DENSE FOG DEVELOPING
OVER THE EASTERN CWA...IN AREAS WHERE SKIES HAVE BEEN MAINLY
CLEAR. MODEL GUIDANCE WITH THIS STRATUS DECK OVER THE LAST DAY OR
TWO HAS BEEN QUITE POOR. THE HRRR APPEARS TO DO THE BEST JOB...BUT
ONLY GOES OUT ABOUT 12 HOURS. THE LATEST RAPID-REFRESH ALSO SEEMS
TO BE OK...AND SPREADS THE CLOUDS OVER MOST OF THE REMAINING CWA
EARLY THIS MORNING AND KEEPS LOWER VISIBILITIES GOING THROUGH
ABOUT 9-10 AM...WITH FOG LIFTING FROM THE NORTHWEST. WILL GO AHEAD
AND ISSUE A DENSE FOG ADVISORY FOR AREAS BETWEEN THE ILLINOIS
RIVER AND I-70 FOR THIS MORNING. TEMPERATURES TODAY WILL BE VERY
TRICKY DEPENDING ON HOW FAST THE CLOUDS FINALLY BREAK UP THIS
AFTERNOON...IF THEY INDEED DO SO. HAVE UNDERCUT GUIDANCE
TEMPERATURES UNDERNEATH BY A FEW DEGREES UNDERNEATH THE STRATUS
DECK...BUT ANY BREAKUP TOO EARLY IN THE DAY WILL CAUSE SIGNIFICANT
ERRORS IN THE HIGH TEMPERATURE FORECAST.

THE OTHER FOCUS DURING THIS PERIOD WILL BE AS A SHORTWAVE...THE
REMNANTS OF A CUTOFF LOW CURRENTLY OVER THE CENTRAL ROCKIES...
INTERACTS WITH ANOTHER WAVE WHICH WILL SWEEP ACROSS THE GREAT
LAKES ON TUESDAY AND WEDNESDAY. STILL NOT A LOT OF MOISTURE
AVAILABILITY WITH THIS SYSTEM...WITH MOST OF THE MODEL GUIDANCE
SUPPORTING LOW CHANCE POPS ACROSS THE SOUTHERN HALF OF THE CWA.
MAY SEE SOME MINOR SNOW ACCUMULATIONS TUESDAY EVENING NEAR THE
I-72 CORRIDOR...DEPENDING ON HOW FAST SURFACE TEMPERATURES DROP
BEFORE THE PRECIPITATION EXITS.

LONG TERM...THURSDAY THROUGH SUNDAY...

MAIN FOCUS IN THIS PERIOD REMAINS WITH ARCTIC AIR MASS WHICH WILL
DROP INTO THE GREAT LAKES LATE IN THE WEEK. COLD FRONT PROGGED TO
MOVE ACROSS THE AREA EARLY FRIDAY MORNING...ALTHOUGH MOST OF THE
MOISTURE WILL BE CLOSER TO THE GREAT LAKES AND WILL GO WITH A DRY
FRONTAL PASSAGE HERE. HOWEVER...LATEST GFS/ECMWF BOTH BRING 850
MB TEMPERATURES AS LOW AS -17C INTO THE CWA BY SATURDAY MORNING...
WHICH WOULD KEEP MUCH OF THE CWA AT OR BELOW FREEZING ON
SATURDAY. AS WITH MOST OF THE COLD PERIODS THIS WINTER...ONLY
LOOKING AT ABOUT A 36-48 HOUR PERIOD WHERE IT WOULD ACTUALLY BE
CONSIDERED TO BE COLD...BEFORE TEMPERATURES QUICKLY RETURN TO NEAR
NORMAL.

GEELHART

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR ILZ031-037-038-
041>057-061>063-066>068-071>073.

&&

$$








AREA FORECAST DISCUSSION

NWS LINCOLN IL

 520 AM CST MON FEB 6 2012

.DISCUSSION...
ISSUED 235 AM CST MON FEB 6 2012

SHORT TERM...TODAY THROUGH WEDNESDAY...

MAIN HEADACHES THE LAST FEW HOURS HAVE BEEN WITH LOW CLOUDS AND
DENSE FREEZING FOG DEVELOPMENT. STRATUS DECK HAS BEEN ADVANCING
SOUTHEASTWARD AND HAD REACHED THE I-55 CORRIDOR AT 2 AM.
VISIBILITIES ALONG THIS EDGE QUICKLY TANKED AND THE 1/4 MILE
VISIBILITY EXTENDS NORTHWEST FOR ABOUT 60 MILES FROM THE LEADING
EDGE. HAVE ALSO BEEN SEEING SOME PATCHIER DENSE FOG DEVELOPING
OVER THE EASTERN CWA...IN AREAS WHERE SKIES HAVE BEEN MAINLY
CLEAR. MODEL GUIDANCE WITH THIS STRATUS DECK OVER THE LAST DAY OR
TWO HAS BEEN QUITE POOR. THE HRRR APPEARS TO DO THE BEST JOB...BUT
ONLY GOES OUT ABOUT 12 HOURS. THE LATEST RAPID-REFRESH ALSO SEEMS
TO BE OK...AND SPREADS THE CLOUDS OVER MOST OF THE REMAINING CWA
EARLY THIS MORNING AND KEEPS LOWER VISIBILITIES GOING THROUGH
ABOUT 9-10 AM...WITH FOG LIFTING FROM THE NORTHWEST. WILL GO AHEAD
AND ISSUE A DENSE FOG ADVISORY FOR AREAS BETWEEN THE ILLINOIS
RIVER AND I-70 FOR THIS MORNING. TEMPERATURES TODAY WILL BE VERY
TRICKY DEPENDING ON HOW FAST THE CLOUDS FINALLY BREAK UP THIS
AFTERNOON...IF THEY INDEED DO SO. HAVE UNDERCUT GUIDANCE
TEMPERATURES UNDERNEATH BY A FEW DEGREES UNDERNEATH THE STRATUS
DECK...BUT ANY BREAKUP TOO EARLY IN THE DAY WILL CAUSE SIGNIFICANT
ERRORS IN THE HIGH TEMPERATURE FORECAST.

THE OTHER FOCUS DURING THIS PERIOD WILL BE AS A SHORTWAVE...THE
REMNANTS OF A CUTOFF LOW CURRENTLY OVER THE CENTRAL ROCKIES...
INTERACTS WITH ANOTHER WAVE WHICH WILL SWEEP ACROSS THE GREAT
LAKES ON TUESDAY AND WEDNESDAY. STILL NOT A LOT OF MOISTURE
AVAILABILITY WITH THIS SYSTEM...WITH MOST OF THE MODEL GUIDANCE
SUPPORTING LOW CHANCE POPS ACROSS THE SOUTHERN HALF OF THE CWA.
MAY SEE SOME MINOR SNOW ACCUMULATIONS TUESDAY EVENING NEAR THE
I-72 CORRIDOR...DEPENDING ON HOW FAST SURFACE TEMPERATURES DROP
BEFORE THE PRECIPITATION EXITS.

LONG TERM...THURSDAY THROUGH SUNDAY...

MAIN FOCUS IN THIS PERIOD REMAINS WITH ARCTIC AIR MASS WHICH WILL
DROP INTO THE GREAT LAKES LATE IN THE WEEK. COLD FRONT PROGGED TO
MOVE ACROSS THE AREA EARLY FRIDAY MORNING...ALTHOUGH MOST OF THE
MOISTURE WILL BE CLOSER TO THE GREAT LAKES AND WILL GO WITH A DRY
FRONTAL PASSAGE HERE. HOWEVER...LATEST GFS/ECMWF BOTH BRING 850
MB TEMPERATURES AS LOW AS -17C INTO THE CWA BY SATURDAY MORNING...
WHICH WOULD KEEP MUCH OF THE CWA AT OR BELOW FREEZING ON
SATURDAY. AS WITH MOST OF THE COLD PERIODS THIS WINTER...ONLY
LOOKING AT ABOUT A 36-48 HOUR PERIOD WHERE IT WOULD ACTUALLY BE
CONSIDERED TO BE COLD...BEFORE TEMPERATURES QUICKLY RETURN TO NEAR
NORMAL.

GEELHART

&&

.AVIATION...
ISSUED 515 AM CST MON FEB 6 2012

DURATION OF VLIFR/LIFR CIGS AND VSBYS TODAY THE MAIN FORECAST
CHALLENGE. THE LOW STRATUS DECK THAT WAS OUT TO OUR NORTHWEST
STARTED TO INCREASE ITS SE MOVEMENT LAST EVENING AND HAS PUSHED
TO JUST NORTH OF THE I-70 CORRIDOR...AND EXTENDS WEST THRU THE
NORTHERN HALF OF MO INTO EXTREME EASTERN NEBRASKA. NOT MUCH
HOPE OF SEEING ANY SIGNIFICANT CLEARING TAKING PLACE TODAY
DESPITE BOUNDARY LAYER WINDS INCREASING OUT OF THE WEST AND
SOUTHWEST. WILL TAKE A MORE PESSIMISTIC OUTLOOK WTIH RESPECT
TO THE CIGS AND VSBYS TODAY AND CONTINUE TO KEEP AT LEAST IFR
CIGS/VSBYS INTO THIS AFTERNOON. THE BIG QUESTION IS HOW QUICKLY
THAT WILL TRANSITION FROM VLIFR TO IFR. BASED ON THE HI-RES
RAPID REFRESH SOLUTION...WILL START TO SEE A GRADUAL IMPROVEMENT
IN CIGS AND VSBYS AFTR 16Z BUT CONTINUE WITH IFR/LIFR CIGS DURING
THE AFTN. REALLY DON`T SEE ANY MECHANISM TO DISPERSE THE CLOUDS
AND IMPROVE THE CIGS SIGNIFICANTLY UNTIL A COLD FRONT MOVES ACRS
THE AREA LATER TONIGHT OR EARLY TUESDAY MORNING.

SURFACE WINDS WILL TEND TO BACK MORE INTO A SOUTHWEST DIRECTION
TODAY AT 8 TO 13 KTS...AND VEER MORE INTO THE WEST AND THEN
NORTHWEST LATE IN THE FORECAST PERIOD AS THE COLD FRONT
APPROACHES.

SMITH
&&

.ILX WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR ILZ031-037-038-
041>057-061.

&&

$$





AREA FORECAST DISCUSSION

NWS LINCOLN IL

 236 AM CST MON FEB 6 2012

.DISCUSSION...
ISSUED 235 AM CST MON FEB 6 2012

SHORT TERM...TODAY THROUGH WEDNESDAY...

MAIN HEADACHES THE LAST FEW HOURS HAVE BEEN WITH LOW CLOUDS AND
DENSE FREEZING FOG DEVELOPMENT. STRATUS DECK HAS BEEN ADVANCING
SOUTHEASTWARD AND HAD REACHED THE I-55 CORRIDOR AT 2 AM.
VISIBILITIES ALONG THIS EDGE QUICKLY TANKED AND THE 1/4 MILE
VISIBILITY EXTENDS NORTHWEST FOR ABOUT 60 MILES FROM THE LEADING
EDGE. HAVE ALSO BEEN SEEING SOME PATCHIER DENSE FOG DEVELOPING
OVER THE EASTERN CWA...IN AREAS WHERE SKIES HAVE BEEN MAINLY
CLEAR. MODEL GUIDANCE WITH THIS STRATUS DECK OVER THE LAST DAY OR
TWO HAS BEEN QUITE POOR. THE HRRR APPEARS TO DO THE BEST JOB...BUT
ONLY GOES OUT ABOUT 12 HOURS. THE LATEST RAPID-REFRESH ALSO SEEMS
TO BE OK...AND SPREADS THE CLOUDS OVER MOST OF THE REMAINING CWA
EARLY THIS MORNING AND KEEPS LOWER VISIBILITIES GOING THROUGH
ABOUT 9-10 AM...WITH FOG LIFTING FROM THE NORTHWEST. WILL GO AHEAD
AND ISSUE A DENSE FOG ADVISORY FOR AREAS BETWEEN THE ILLINOIS
RIVER AND I-70 FOR THIS MORNING. TEMPERATURES TODAY WILL BE VERY
TRICKY DEPENDING ON HOW FAST THE CLOUDS FINALLY BREAK UP THIS
AFTERNOON...IF THEY INDEED DO SO. HAVE UNDERCUT GUIDANCE
TEMPERATURES UNDERNEATH BY A FEW DEGREES UNDERNEATH THE STRATUS
DECK...BUT ANY BREAKUP TOO EARLY IN THE DAY WILL CAUSE SIGNIFICANT
ERRORS IN THE HIGH TEMPERATURE FORECAST.

THE OTHER FOCUS DURING THIS PERIOD WILL BE AS A SHORTWAVE...THE
REMNANTS OF A CUTOFF LOW CURRENTLY OVER THE CENTRAL ROCKIES...
INTERACTS WITH ANOTHER WAVE WHICH WILL SWEEP ACROSS THE GREAT
LAKES ON TUESDAY AND WEDNESDAY. STILL NOT A LOT OF MOISTURE
AVAILABILITY WITH THIS SYSTEM...WITH MOST OF THE MODEL GUIDANCE
SUPPORTING LOW CHANCE POPS ACROSS THE SOUTHERN HALF OF THE CWA.
MAY SEE SOME MINOR SNOW ACCUMULATIONS TUESDAY EVENING NEAR THE
I-72 CORRIDOR...DEPENDING ON HOW FAST SURFACE TEMPERATURES DROP
BEFORE THE PRECIPITATION EXITS.


LONG TERM...THURSDAY THROUGH SUNDAY...

MAIN FOCUS IN THIS PERIOD REMAINS WITH ARCTIC AIR MASS WHICH WILL
DROP INTO THE GREAT LAKES LATE IN THE WEEK. COLD FRONT PROGGED TO
MOVE ACROSS THE AREA EARLY FRIDAY MORNING...ALTHOUGH MOST OF THE
MOISTURE WILL BE CLOSER TO THE GREAT LAKES AND WILL GO WITH A DRY
FRONTAL PASSAGE HERE. HOWEVER...LATEST GFS/ECMWF BOTH BRING 850
MB TEMPERATURES AS LOW AS -17C INTO THE CWA BY SATURDAY MORNING...
WHICH WOULD KEEP MUCH OF THE CWA AT OR BELOW FREEZING ON
SATURDAY. AS WITH MOST OF THE COLD PERIODS THIS WINTER...ONLY
LOOKING AT ABOUT A 36-48 HOUR PERIOD WHERE IT WOULD ACTUALLY BE
CONSIDERED TO BE COLD...BEFORE TEMPERATURES QUICKLY RETURN TO NEAR
NORMAL.

GEELHART

&&

.AVIATION...
ISSUED 1150 PM CST SUN FEB 5 2012

GOING TO BE PESSIMISTIC THROUGH THE PERIOD WITH THE TAFS. LARGE
AREA OF VLIFR CONDITIONS HAS BEEN APPROACHING THE AREA ALL NIGHT
AND HAS FINALLY REACHED PIA. BASED ON SHORT RANGE HIGH RES
MODELS...BELIEVE THIS TREND WILL CONTINUE INTO SPI/BMI/DEC DURING
THE OVERNIGHT HOURS. THINK IT WILL ALSO REACH CMI BUT TOWARD
MORNING. IN ADDITION...LIGHT FOG HAS BEEN DEVELOPING AT THE SITES
WITH NO CLOUDS. ONCE CLOUD COVER REACHES THESE SITES...VIS WILL
PROBABLY DECREASE AGAIN. THE OVERALL BIG QUESTION IS WILL THERE BE
ANY IMPROVEMENT DURING THE DAY TOMORROW. SHORT TERM HIGH RES
MODELS DO NOT EXTENDED QUITE FAR ENOUGH...BUT BASED ON PERSISTANCE
FROM TODAY ACROSS IOWA AND SEEING THERE IS NOT FRONT AND DRIER
AIR FORECAST TO MOVE INTO THE AREA TOMORROW...BELIEVE ONLY
IMPROVEMENT WILL BE WITH VISIBILITIES AS THE WINDS INCREASE FROM
THE WEST-SOUTHWEST DURING THE MORNING. WILL KEEP CIGS BELOW 1KFT
THROUGH THE ENTIRE FORECAST PERIOD. WINDS WILL DECREASE AROUND
SUNSET AT ALL SITES SO BELIEVE VIS WILL FALL AGAIN TO AROUND 3SM.
COULD GO LOWER BUT VERY UNSURE AT THIS TIME. WINDS WILL BE LIGHT
TONIGHT BUT INCREASE IN SPEED OUT OF THE WEST-SOUTHWEST
TOMORROW...THEN DECREASE AGAIN TOMORROW EVENING.

AUTEN

&&

.ILX WATCHES/WARNINGS/ADVISORIES...

DENSE FOG ADVISORY FOR ILZ031-037-038-041>057-061 UNTIL NOON CST.

&&

$$






AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 932 PM EST TUE FEB 7 2012

.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...AN UPPER DISTURBANCE WILL MOVE THROUGH CENTRAL INDIANA
OVERNIGHT AND EARLY WEDNESDAY MORNING BRINGING MEASURABLE SNOW TO
MUCH OF THE AREA FOR THE MORNING COMMUTE. BY WEDNESDAY AFTERNOON
HIGH PRESSURE RIDGING WILL BUILD INTO THE AREA AND BRING DRY WEATHER
UNTIL THE NEXT WAVE ARRIVES ON FRIDAY WITH MORE CHANCES FOR SNOW
THROUGH FRIDAY NIGHT. AFTER THAT THE WEATHER WILL BE QUIET UNTIL THE
NEXT WAVE APPROACHES FOR MONDAY NIGHT.

&&

.NEAR TERM /TONIGHT/...

RADAR MOSAICS CONTINUE TO INDICATE PRECIP CONTINUING TO DEVELOP
ACROSS SE MO AND SOUTHERN ILLINOIS PUSHING NORTHEAST. GIVEN THE
LACK OF ANY PRECIP OVER THE NEXT COUPLE OVER HOURS...HAVE REMOVED
POPS UNTIL AFTER MIDNIGHT. RUC FORECAST SOUNDINGS INDICATE
SATURATION THROUGH THE COLUMN AFTER 09Z. TIME HEIGHT SECTIONS SHOW
SATURATION CONTINUING THROUGH TE MORNING RUSH HOURS...THUS WILL
ISSUE ANOTHER SPS TO HIGHLIGHT THIS. BASED ON RUC AND TEMPS
EXPECTED TO APPROACH WET BULB TEMPS...HAVE TRENDED LOW TEMPS
WARMER.

&&

.SHORT TERM /WEDNESDAY AFTERNOON THROUGH FRIDAY/...

MODELS ARE IN GOOD AGREEMENT SO WILL USE A CONSENSUS APPROACH. THE
UPPER WAVE IS THROUGH THE AREA BY WEDNESDAY AFTERNOON WITH UPPER
RIDGING MOVING INTO THE AREA. THIS WILL KEEP THINGS DRY UNTIL FRIDAY
WHEN ANOTHER WAVE APPROACHES AND BRINGS LOW CHANCES FOR SNOW. FOR
TEMPERATURES GENERALLY WENT NEAR A GUIDANCE AVERAGE...BUT USED
TEMPERATURES COOLER THAN GUIDANCE FOR WEDNESDAY AND FRIDAY HIGHS
WITH COLD ADVECTION AND EXPECTED CLOUD COVER. THIS YIELDED
TEMPERATURES NEAR AVERAGE FOR THIS TIME OF YEAR.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

THE BEST CHANCES OF PRECIP WILL BE DURING THE FRIDAY NIGHT PERIOD AS
A STRONG UPPER TROUGH ROTATES EAST ACROSS THE GREAT LAKES AND AGAIN
TOWARDS MONDAY NIGHT WARM ADVECTION INCREASES AND A WEAK UPPER LEVEL
DISTURBANCE MOVES THROUGH THE OHIO VALLEY.

WENT PRETTY MUCH TO ALL BLEND POPS FRIDAY NIGHT.  BUT IN THE NORTH I
INCREASED THEM A LITTLE AS THERE COULD BE SOME LAKE ENHANCEMENT.
THIS LAKE ENHANCEMENT MAY LINGER INTO SATURDAY SO KEPT SLIGHT
CHANCES ACROSS MUCH OF OUR FAR NORTH.  MODELS HAVE TRENDED COLDER
OVER THE WEEKEND AND WENT CLOSER TO THE CONSALL NUMBERS AS THE COLD
UPPER TROUGH MOVES ACROSS THE GREAT LAKES OVER THE WEEKEND.

HIGH PRESSURE WILL MOVE ACROSS OUR REGION SUNDAY AND WARM ADVECTION
STARTS MONDAY.  MODELS HAVE TRENDED SLOWER...SO WILL ONLY MENTION
SLIGHT CHANCE OF PRECIP ACROSS OUR FAR SOUTHWEST LATE MONDAY.

MOST MODELS PRODUCE LIGHT PRECIP AMOUNTS AND THICKNESS SHOULD BE LOW
ENOUGH FOR MOSTLY SNOW NORTH AND CENTRAL MONDAY NIGHT.  RAISED
TEMPERATURES A LITTLE WITH CLOUDS AND WARM ADVECTION MONDAY NIGHT.
ALL BLEND TEMPERATURES MAY BE A TAD WARM TUESDAY AS THERE WILL BE
LOTS OF CLOUDS.  BUT ONLY CHANGE I MADE WAS TO LOWER THE NORTH HALF
A FEW DEGREES IN CASE THERE WAS SOME LEFT OVER SNOWFALL FROM MONDAY
NIGHT.

&&

.AVIATION /DISCUSSION FOR THE 080300Z KIND TAF UPDATE/...

STARTING TO SEE QUITE OF BIT OF MVFR VISIBILITY RESTRICTIONS DUE TO
LIGHT FOG/HAZE UPSTREAM...SO WILL DROP THE VISIBILITY FORECAST INTO
THE MVFR CATEGORY FOR THE REST OF THE EVENING. SOME PATCHES OF IFR
CEILINGS 006-009 AGL STARTING TO SHOW UP AS WELL. NOT WIDESPREAD
ENOUGH YET TO INCLUDE IN THE FORECAST...BUT THE POSSIBILITY EXISTS
FOR IFR CEILINGS TO AT LEAST TEMPORARILY AFFECT KIND WITHIN THE NEXT
FEW HOURS. PREVIOUS DISCUSSION FOLLOWS.

LOWER CONFIDENCE CEILING FORECAST THIS EVENING AS THE EDGE OF AN
MVFR DECK EXISTS BETWEEN KIND/KHUF/KBMG. THE EDGE HAS BEEN
RETREATING A BIT TO THE NORTHEAST OVER THE PAST COUPLE OF
HOURS...HOWEVER THE LOW LEVEL NORTHEAST FLOW AND SHORT TERM MODELS
SUGGEST THE EDGE WILL BEGIN DRIFTING BACK TO THE SOUTHWEST LATER
THIS EVENING. FOR NOW WILL KEEP MVFR CEILINGS AT KLAF/KIND...AND GO
WITH TEMPORARY MVFR CEILINGS AT KHUF/KBMG...WITH PREVAILING MVFR
CEILINGS OVERSPREADING ALL THE TAF SITES BY 080500Z.

OTHER ITEM OF INTEREST OVERNIGHT WILL BE THE SYSTEM CURRENTLY MOVING
THROUGH IOWA AND MISSOURI. HIGHER RESOLUTION SHORT TERM MODELS
SUGGEST THERE IS GOOD POTENTIAL FOR FAIRLY WIDESPREAD IFR VISIBILITY
RESTRICTIONS IN LIGHT SNOW ACROSS THE AREA AFTER ABOUT 080900Z.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CP
NEAR TERM...PUMA
SHORT TERM...CP
LONG TERM....JH
AVIATION...JAS








AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 911 PM EST TUE FEB 7 2012

.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW

&&

.SYNOPSIS...AN UPPER DISTURBANCE WILL MOVE THROUGH CENTRAL INDIANA
OVERNIGHT AND EARLY WEDNESDAY MORNING BRINGING MEASURABLE SNOW TO
MUCH OF THE AREA FOR THE MORNING COMMUTE. BY WEDNESDAY AFTERNOON
HIGH PRESSURE RIDGING WILL BUILD INTO THE AREA AND BRING DRY WEATHER
UNTIL THE NEXT WAVE ARRIVES ON FRIDAY WITH MORE CHANCES FOR SNOW
THROUGH FRIDAY NIGHT. AFTER THAT THE WEATHER WILL BE QUIET UNTIL THE
NEXT WAVE APPROACHES FOR MONDAY NIGHT.

&&

.NEAR TERM /TONIGHT/...

RADAR MOSAICS CONTINUE TO INDICATE PRECIP CONTINUING TO DEVELOP
ACROSS SE MO AND SOUTHERN ILLINOIS PUSHING NORTHEAST. GIVEN THE
LACK OF ANY PRECIP OVER THE NEXT COUPLE OVER HOURS...HAVE REMOVED
POPS UNTIL AFTER MIDNIGHT. RUC FORECAST SOUNDINGS INDICATE
SATURATION THROUGH THE COLUMN AFTER 09Z. TIME HEIGHT SECTIONS SHOW
SATURATION CONTINUING THROUGH TE MORNING RUSH HOURS...THUS WILL
ISSUE ANOTHER SPS TO HIGHLIGHT THIS. BASED ON RUC AND TEMPS
EXPECTED TO APPROACH WET BULB TEMPS...HAVE TRENDED LOW TEMPS
WARMER.

&&

.SHORT TERM /WEDNESDAY AFTERNOON THROUGH FRIDAY/...

MODELS ARE IN GOOD AGREEMENT SO WILL USE A CONSENSUS APPROACH. THE
UPPER WAVE IS THROUGH THE AREA BY WEDNESDAY AFTERNOON WITH UPPER
RIDGING MOVING INTO THE AREA. THIS WILL KEEP THINGS DRY UNTIL FRIDAY
WHEN ANOTHER WAVE APPROACHES AND BRINGS LOW CHANCES FOR SNOW. FOR
TEMPERATURES GENERALLY WENT NEAR A GUIDANCE AVERAGE...BUT USED
TEMPERATURES COOLER THAN GUIDANCE FOR WEDNESDAY AND FRIDAY HIGHS
WITH COLD ADVECTION AND EXPECTED CLOUD COVER. THIS YIELDED
TEMPERATURES NEAR AVERAGE FOR THIS TIME OF YEAR.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

THE BEST CHANCES OF PRECIP WILL BE DURING THE FRIDAY NIGHT PERIOD AS
A STRONG UPPER TROUGH ROTATES EAST ACROSS THE GREAT LAKES AND AGAIN
TOWARDS MONDAY NIGHT WARM ADVECTION INCREASES AND A WEAK UPPER LEVEL
DISTURBANCE MOVES THROUGH THE OHIO VALLEY.

WENT PRETTY MUCH TO ALL BLEND POPS FRIDAY NIGHT.  BUT IN THE NORTH I
INCREASED THEM A LITTLE AS THERE COULD BE SOME LAKE ENHANCEMENT.
THIS LAKE ENHANCEMENT MAY LINGER INTO SATURDAY SO KEPT SLIGHT
CHANCES ACROSS MUCH OF OUR FAR NORTH.  MODELS HAVE TRENDED COLDER
OVER THE WEEKEND AND WENT CLOSER TO THE CONSALL NUMBERS AS THE COLD
UPPER TROUGH MOVES ACROSS THE GREAT LAKES OVER THE WEEKEND.

HIGH PRESSURE WILL MOVE ACROSS OUR REGION SUNDAY AND WARM ADVECTION
STARTS MONDAY.  MODELS HAVE TRENDED SLOWER...SO WILL ONLY MENTION
SLIGHT CHANCE OF PRECIP ACROSS OUR FAR SOUTHWEST LATE MONDAY.

MOST MODELS PRODUCE LIGHT PRECIP AMOUNTS AND THICKNESS SHOULD BE LOW
ENOUGH FOR MOSTLY SNOW NORTH AND CENTRAL MONDAY NIGHT.  RAISED
TEMPERATURES A LITTLE WITH CLOUDS AND WARM ADVECTION MONDAY NIGHT.
ALL BLEND TEMPERATURES MAY BE A TAD WARM TUESDAY AS THERE WILL BE
LOTS OF CLOUDS.  BUT ONLY CHANGE I MADE WAS TO LOWER THE NORTH HALF
A FEW DEGREES IN CASE THERE WAS SOME LEFT OVER SNOWFALL FROM MONDAY
NIGHT.

&&

.AVIATION /DISCUSSION FOR THE 080000Z TAFS/...

LOWER CONFIDENCE CEILING FORECAST THIS EVENING AS THE EDGE OF AN
MVFR DECK EXISTS BETWEEN KIND/KHUF/KBMG. THE EDGE HAS BEEN
RETREATING A BIT TO THE NORTHEAST OVER THE PAST COUPLE OF
HOURS...HOWEVER THE LOW LEVEL NORTHEAST FLOW AND SHORT TERM MODELS
SUGGEST THE EDGE WILL BEGIN DRIFTING BACK TO THE SOUTHWEST LATER
THIS EVENING. FOR NOW WILL KEEP MVFR CEILINGS AT KLAF/KIND...AND GO
WITH TEMPORARY MVFR CEILINGS AT KHUF/KBMG...WITH PREVIALING MVFR
CEILINGS OVERSPREADING ALL THE TAF SITES BY 080500Z.

OTHER ITEM OF INTEREST OVERNIGHT WILL BE THE SYSTEM CURRENTLY MOVING
THROUGH IOWA AND MISSOURI. HIGHER RESOLUTION SHORT TERM MODELS
SUGGEST THERE IS GOOD POTENTIAL FOR FAIRLY WIDESPREAD IFR VISIBILITY
RESTRICTIONS IN LIGHT SNOW ACROSS THE AREA AFTER ABOUT 080900Z.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CP
NEAR TERM...PUMA
SHORT TERM...CP
LONG TERM....JH
AVIATION...JAS





AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 354 PM EST MON FEB 6 2012

.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...

HIGH PRESSURE WILL GIVE WAY TO AN UPPER WAVE TUESDAY NIGHT THAT
WILL BRING SMALL CHANCES FOR SNOW TO CENTRAL INDIANA INTO
WEDNESDAY MORNING. ANOTHER COUPLE OF WEAK WAVES WILL MOVE THROUGH
EARLY IN THE WEEKEND AND AGAIN ON MONDAY AND BRING MORE SMALL
CHANCES FOR PRECIPITATION. TEMPERATURES WILL ACTUALLY DROP TO NEAR
NORMAL FROM MIDWEEK THROUGH THE WEEKEND WITH BROAD TROUGHING OVER
THE EASTERN PART OF THE COUNTRY.

&&

.NEAR TERM /TONIGHT/...

WITH HIGH PRESSURE SUBSIDENCE OVER THE AREA AND A STRATUS DECK TO
THE WEST WITH WESTERLY LOW LEVEL FLOW OVERNIGHT THINK STRATUS WILL
ADVECT BACK INTO THE NORTHWEST AND OVERSPREAD THE NORTHWESTERN TWO
THIRDS OF THE AREA DURING THE OVERNIGHT HOURS SINCE THERE WILL BE
NOTHING TO STOP IT. WHILE LARGE SCALE MODELS DO NOT DO A GOOD JOB
DEPICTING THIS LOW LEVEL RH FIELDS AND SOUNDINGS FROM THE RUC SHOW
THIS POTENTIAL AND THE RUC DID A MUCH BETTER JOB HANDLING WHAT
HAPPENED THIS MORNING. COULD ALSO SEE SOME PATCHY FOG ACROSS THE
AREA. NOT SURE OF EXTENT OR SPECIFIC LOCATION OF FOG...BUT WITH
RECENT MORNINGS AND FORECAST SOUNDINGS WILL GO AHEAD AND PUT PATCHY
FOG EVERYWHERE. WITH THE INCREASE IN CLOUD COVER THAT THE GFS AND
NAM DON/T HAVE ALSO WENT WITH WARMER LOWS THAN GUIDANCE OVER ALL BUT
THE SOUTHEAST WHERE STRATUS MAY NOT REACH.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...

FORECAST FOCUS IS ON CLOUD COVER TUESDAY AND POPS WITH TUESDAY
NIGHT/WEDNESDAY SYSTEM. MODELS ARE IN DECENT AGREEMENT AND WILL USE
A CONSENSUS APPROACH FOR THE MOST PART.

AFOREMENTIONED STRATUS MAY ERODE SOME IN THE LATE MORNING TUESDAY BUT
WILL ALSO START TO SEE AN INCREASE IN CLOUDS AS THE NEXT UPPER WAVE
APPROACHES FROM THE NORTHWEST...SO NET RESULT SHOULD BE MOSTLY
CLOUDY SKIES TO EVEN CLOUDY SKIES IN THE NORTHWEST. WITH MORE CLOUD
COVER IN THE NORTH AND CENTRAL WILL ALSO DROP HIGHS THERE FROM
GUIDANCE. THE UPPER WAVE MOVING IN TUESDAY NIGHT PROVIDES ONLY WEAK
TO AT MOST MODERATE UPPER LEVEL FORCING AND THERE IS NOTHING ELSE
HELPING THIS SYSTEM...NO INSTABILITY...NO LOW LEVEL FORCING...AND
LITTLE MOISTURE. THE BEST FORCING STILL APPEARS TO BE MOVING THROUGH
BETWEEN 6 AND 12Z AND THUS KEPT LOW CHANCE POPS GOING THEN WITH
SLIGHT CHANCES FOR 6 HOURS ON EITHER SIDE. SOUNDINGS IN ALL BUT THE
SOUTH LOOK COLD ENOUGH FOR ALL SNOW. WILL START WITH A RAIN SNOW MIX
IN THE SOUTH BEFORE CHANGING OVER TO ALL SNOW. LITTLE TO NO
ACCUMULATION EXPECTED.

BY WEDNESDAY 18Z THE UPPER WAVE HAS MOVED OUT OF THE AREA AND
RIDGING IS MOVING BACK INTO THE AREA FROM THEN ON SO DRY WEATHER
FROM THAT POINT THROUGH THURSDAY. WENT COOLER THAN GUIDANCE
WEDNESDAY WITH COLD ADVECTION OCCURRING.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...

OVERALL THE EXTENDED WILL BE A QUIET PERIOD. HOWEVER THERE ARE TWO
SYSTEMS THAT MAY GIVE LOW CHANCES OF PRECIP.  ONE PERIOD IS FRIDAY
AFTERNOON AND NIGHT AS COLD FRONT MOVES THROUGH FRIDAY AFTERNOON
FOLLOWED BY AN UPPER TROUGH FRIDAY NIGHT AND SATURDAY. THE GFS STILL
HAS US DRY...BUT THE EUROPEAN AND CANADIAN AS WELL AS CONSALL GIVES
US LOW CHANCES OF PRECIPITATION.  TEMPERATURES MAY BE WARM ENOUGH
FOR MIXED PRECIP ACROSS OUR SOUTH FRIDAY AFTERNOON. OTHERWISE...WILL
GO WITH A SLIGHT CHANCE OF SNOW SHOWERS.

THE UPPER TROUGH MOVES ON TO THE EAST OVER THE WEEKEND AND WARM
ADVECTION SETS UP BY MONDAY AHEAD OF THE NEXT SYSTEM.  THE GFS
BARELY BRINGS PRECIP INTO OUR NORTHWEST BY 00Z TUESDAY AND THE
EUROPEAN IS EVEN SLOWER.  WILL TRIM POPS A LITTLE...BUT KEEP LOW
CHANCES ACROSS OUR WEST BY LATE DAY 7.  DID NOT MAKE ANY SIGNIFICANT
CHANGE TO ALL BLEND TEMPERATURES.

&&

.AVIATION /DISCUSSION FOR THE 06/18Z TAF ISSUANCE/...

2030Z UPDATE...KIND AVIATION FORECAST PRETTY MUCH REPRESENTATIVE...ONLY
ADDED IN SOME FEW CU FOR THE NEXT HOURS BASED ON TRENDS. HOWEVER...KLAF
LOOKS TO REMAIN AT IFR FOR AT LEAST THE NEXT FEW HOURS AS THAT
STRATUS DECK HANGS ON A BIT LONGER. PREVIOUS DISCUSSION
FOLLOWS....

EASTERN EDGE OF STRATUS/FOG DECK NEAR KOKOMO TO KHUF LINE WILL START
ERODING THIS AFTERNOON AND BOTH KHUF AND KLAF TAFS WILL IMPROVE TO
VFR BY LATE AFTERNOON.  FARTHER WEST THAT THIS STRATUS DECK WILL
REMAIN INTACT AND START SPREADING EASTWARD AGAIN DURING THE
OVERNIGHT HOURS.  THE RUC SOUNDING INDICATES THIS OCCURRING
OVERNIGHT AT MOST TAF SITES. BUT THERE IS MORE UNCERTAINTY WHETHER
THIS STRATUS/FOG DECK REACHES KBMG.  FOR NOW WILL PLAY IT THAT
WAY...BUT HAPPENING LATER TONIGHT.  THUS ALL TAFS WILL BECOME IFR OR
LIFR DURING THE OVERNIGHT HOURS.  BUFKIT IS SOMEWHAT NEUTRAL ON
WHETHER THIS WILL BE MOSTLY STRATUS OR FOG.  BUT IN AREAS WHERE
STRATUS ADVECT IN...IT MAY KEEP VISIBILITIES FROM DROPPING TOO LOW.

ON TUESDAY...THERE MAY BE SOME IMPROVEMENT ACROSS THE SOUTHERN HALF
OF OUR REGION. A COLD FRONT WILL MOVE INTO OUR REGION LATE TUESDAY.
WINDS WILL BE WEST OR SOUTHWEST AT 6 TO 8 KNOTS THIS AFTERNOON AND
LESS THAN 5 KNOTS TONIGHT.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CP
NEAR TERM...CP
SHORT TERM...CP
LONG TERM....JH
AVIATION...JH/SMF







AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 332 PM EST MON FEB 6 2012

.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM AND LONG TERM SECTIONS HAVE
BEEN UPDATED BELOW.

&&

.SYNOPSIS...

HIGH PRESSURE WILL GIVE WAY TO AN UPPER WAVE TUESDAY NIGHT THAT
WILL BRING SMALL CHANCES FOR SNOW TO CENTRAL INDIANA INTO
WEDNESDAY MORNING. ANOTHER COUPLE OF WEAK WAVES WILL MOVE THROUGH
EARLY IN THE WEEKEND AND AGAIN ON MONDAY AND BRING MORE SMALL
CHANCES FOR PRECIPITATION. TEMPERATURES WILL ACTUALLY DROP TO NEAR
NORMAL FROM MIDWEEK THROUGH THE WEEKEND WITH BROAD TROUGHING OVER
THE EASTERN PART OF THE COUNTRY.

&&

.NEAR TERM /TONIGHT/...

WITH HIGH PRESSURE SUBSIDENCE OVER THE AREA AND A STRATUS DECK TO
THE WEST WITH WESTERLY LOW LEVEL FLOW OVERNIGHT THINK STRATUS WILL
ADVECT BACK INTO THE NORTHWEST AND OVERSPREAD THE NORTHWESTERN TWO
THIRDS OF THE AREA DURING THE OVERNIGHT HOURS SINCE THERE WILL BE
NOTHING TO STOP IT. WHILE LARGE SCALE MODELS DO NOT DO A GOOD JOB
DEPICTING THIS LOW LEVEL RH FIELDS AND SOUNDINGS FROM THE RUC SHOW
THIS POTENTIAL AND THE RUC DID A MUCH BETTER JOB HANDLING WHAT
HAPPENED THIS MORNING. COULD ALSO SEE SOME PATCHY FOG ACROSS THE
AREA. NOT SURE OF EXTENT OR SPECIFIC LOCATION OF FOG...BUT WITH
RECENT MORNINGS AND FORECAST SOUNDINGS WILL GO AHEAD AND PUT PATCHY
FOG EVERYWHERE. WITH THE INCREASE IN CLOUD COVER THAT THE GFS AND
NAM DON/T HAVE ALSO WENT WITH WARMER LOWS THAN GUIDANCE OVER ALL BUT
THE SOUTHEAST WHERE STRATUS MAY NOT REACH.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...

FORECAST FOCUS IS ON CLOUD COVER TUESDAY AND POPS WITH TUESDAY
NIGHT/WEDNESDAY SYSTEM. MODELS ARE IN DECENT AGREEMENT AND WILL USE
A CONSENSUS APPROACH FOR THE MOST PART.

AFOREMENTIONED STRATUS MAY ERODE SOME IN THE LATE MORNING TUESDAY BUT
WILL ALSO START TO SEE AN INCREASE IN CLOUDS AS THE NEXT UPPER WAVE
APPROACHES FROM THE NORTHWEST...SO NET RESULT SHOULD BE MOSTLY
CLOUDY SKIES TO EVEN CLOUDY SKIES IN THE NORTHWEST. WITH MORE CLOUD
COVER IN THE NORTH AND CENTRAL WILL ALSO DROP HIGHS THERE FROM
GUIDANCE. THE UPPER WAVE MOVING IN TUESDAY NIGHT PROVIDES ONLY WEAK
TO AT MOST MODERATE UPPER LEVEL FORCING AND THERE IS NOTHING ELSE
HELPING THIS SYSTEM...NO INSTABILITY...NO LOW LEVEL FORCING...AND
LITTLE MOISTURE. THE BEST FORCING STILL APPEARS TO BE MOVING THROUGH
BETWEEN 6 AND 12Z AND THUS KEPT LOW CHANCE POPS GOING THEN WITH
SLIGHT CHANCES FOR 6 HOURS ON EITHER SIDE. SOUNDINGS IN ALL BUT THE
SOUTH LOOK COLD ENOUGH FOR ALL SNOW. WILL START WITH A RAIN SNOW MIX
IN THE SOUTH BEFORE CHANGING OVER TO ALL SNOW. LITTLE TO NO
ACCUMULATION EXPECTED.

BY WEDNESDAY 18Z THE UPPER WAVE HAS MOVED OUT OF THE AREA AND
RIDGING IS MOVING BACK INTO THE AREA FROM THEN ON SO DRY WEATHER
FROM THAT POINT THROUGH THURSDAY. WENT COOLER THAN GUIDANCE
WEDNESDAY WITH COLD ADVECTION OCCURRING.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...

OVERALL THE EXTENDED WILL BE A QUIET PERIOD. HOWEVER THERE ARE TWO
SYSTEMS THAT MAY GIVE LOW CHANCES OF PRECIP.  ONE PERIOD IS FRIDAY
AFTERNOON AND NIGHT AS COLD FRONT MOVES THROUGH FRIDAY AFTERNOON
FOLLOWED BY AN UPPER TROUGH FRIDAY NIGHT AND SATURDAY. THE GFS STILL
HAS US DRY...BUT THE EUROPEAN AND CANADIAN AS WELL AS CONSALL GIVES
US LOW CHANCES OF PRECIPITATION.  TEMPERATURES MAY BE WARM ENOUGH
FOR MIXED PRECIP ACROSS OUR SOUTH FRIDAY AFTERNOON. OTHERWISE...WILL
GO WITH A SLIGHT CHANCE OF SNOW SHOWERS.

THE UPPER TROUGH MOVES ON TO THE EAST OVER THE WEEKEND AND WARM
ADVECTION SETS UP BY MONDAY AHEAD OF THE NEXT SYSTEM.  THE GFS
BARELY BRINGS PRECIP INTO OUR NORTHWEST BY 00Z TUESDAY AND THE
EUROPEAN IS EVEN SLOWER.  WILL TRIM POPS A LITTLE...BUT KEEP LOW
CHANCES ACROSS OUR WEST BY LATE DAY 7.  DID NOT MAKE ANY SIGNIFICANT
CHANGE TO ALL BLEND TEMPERATURES.

&&

.AVIATION /DISCUSSION FOR THE 06/18Z TAF ISSUANCE/...

EASTERN EDGE OF STRATUS/FOG DECK NEAR KOKOMO TO KHUF LINE WILL START
ERODING THIS AFTERNOON AND BOTH KHUF AND KLAF TAFS WILL IMPROVE TO
VFR BY LATE AFTERNOON.  FARTHER WEST THAT THIS STRATUS DECK WILL
REMAIN INTACT AND START SPREADING EASTWARD AGAIN DURING THE
OVERNIGHT HOURS.  THE RUC SOUNDING INDICATES THIS OCCURRING
OVERNIGHT AT MOST TAF SITES. BUT THERE IS MORE UNCERTAINTY WHETHER
THIS STRATUS/FOG DECK REACHES KBMG.  FOR NOW WILL PLAY IT THAT
WAY...BUT HAPPENING LATER TONIGHT.  THUS ALL TAFS WILL BECOME IFR OR
LIFR DURING THE OVERNIGHT HOURS.  BUFKIT IS SOMEWHAT NEUTRAL ON
WHETHER THIS WILL BE MOSTLY STRATUS OR FOG.  BUT IN AREAS WHERE
STRATUS ADVECT IN...IT MAY KEEP VISIBILITIES FROM DROPPING TOO LOW.

ON TUESDAY...THERE MAY BE SOME IMPROVEMENT ACROSS THE SOUTHERN HALF
OF OUR REGION. A COLD FRONT WILL MOVE INTO OUR REGION LATE TUESDAY.
WINDS WILL BE WEST OR SOUTHWEST AT 6 TO 8 KNOTS THIS AFTERNOON AND
LESS THAN 5 KNOTS TONIGHT.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CP
NEAR TERM...CP
SHORT TERM...CP
LONG TERM....JH
AVIATION...JH





AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 1207 PM AM EST MON FEB 6 2012

.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...

HIGH PRESSURE WILL KEEP DRY MILD WEATHER ACROSS CENTRAL INDIANA
THROUGH TUESDAY. A SERIES OF WEAK UPPER LEVEL DISTURBANCES WILL
BRING THE CHANCE FOR LIGHT PRECIPITATION TUESDAY NIGHT AND
WEDNESDAY. HIGH PRESSURE WILL BRING A RETURN TO DRY WEATHER FOR LATE
WEEK AND INTO THE WEEKEND. THE EXPANSION OF A BROAD UPPER LEVEL
TROUGH WILL SIGNAL A SHIFT TO COLDER TEMPERATURES BY THE WEEKEND.

&&

.NEAR TERM /REST OF TODAY/...
FOG OVER THE NORTHWESTERN COUNTIES CONTINUES TO HANG IN THERE WITH
VISIBILITIES AT OR BELOW A QUARTER MILE AND TEMPERATURES RIGHT
AROUND THE FREEZING MARK...SO EXTENDED ADVISORY THROUGH 18Z. WITH
THINNING SEEN ON VISIBLE SATELLITE AND TEMPERATURES AT LEAST NOW
CLIMBING TO FREEZING THINK IMPROVEMENTS WILL BE SUFFICIENT BY 18Z
TO ALLOW END OF ADVISORY THEN. FOG AND LOW CLOUDS ARE INHIBITING
WARMING IN THE AFOREMENTIONED AREA AND THUS LOWERED TEMPERATURES
THERE FOR THE AFTERNOON...BUT ELSEWHERE THINK UPPER 40S TO AROUND
50 WILL BE ACHIEVABLE UNDER SUNNY SKIES.


&&

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...

FORECAST CHALLENGES FOCUS ON PRECIP CHANCES TUESDAY NIGHT AND
WEDNESDAY AS A SERIES OF WEAK UPPER LEVEL DISTURBANCES PASS THROUGH
THE LOWER GREAT LAKES.

HIGH PRESSURE RIDGE WILL BRING ANOTHER TRANQUIL NIGHT WITH CLEAR
SKIES TONIGHT. THE RIDGE SHIFTS EAST TUESDAY WITH MID AND HIGH LEVEL
CLOUDS EXPANDING INTO THE REGION FROM THE NORTHWEST. CHANCES FOR
PRECIPITATION ARE LIKELY TO HOLD OFF UNTIL TUESDAY EVENING AS LEAD
SHORTWAVE ASSOCIATED WITHIN LARGER UPPER TROUGH ROTATES ACROSS THE
REGION. ISENTROPIC LIFT AND OVERALL FORCING REMAIN GENERALLY
WEAK...BUT DOES APPEAR ENOUGH MOISTURE PRESENT FOR LIGHT
PRECIPITATION. WHILE A LIGHT RAIN/SNOW MIX IS POSSIBLE OVER SOUTHERN
COUNTIES TUESDAY EVENING...LOW LEVEL THERMALS AND MODEL SOUNDINGS
SHOW PRECIPITATION AS ALL SNOW AFTER MIDNIGHT AS THE BOUNDARY LAYER
AND NEAR SURFACE TEMPS COOL. SHORTWAVE AXIS SWINGS ACROSS THE
FORECAST AREA BETWEEN 06-12Z WEDNESDAY WITH BEST FORCING ALOFT. THIS
LIKELY TO BE THE TIMEFRAME WHEN LIGHT SNOW IS MOST PREVALENT WITH
HIGHEST POPS. APPEARS THERE COULD BE A FEW TENTHS OF AN INCH
ACCUMULATION BY DAYBREAK WEDNESDAY.

SCATTERED LIGHT SNOW SHOWERS WILL PERSIST WEDNESDAY MORNING WITH A
GRADUAL DIMINISHING OF COVERAGE AS BETTER MOISTURE AND FORCING SHIFT
EAST THROUGH THE DAY. CLOUDS AND A FEW FLURRIES LIKELY TO LINGER
UNTIL THE MAIN UPPER TROUGH PASSES WEDNESDAY AFTERNOON. WILL HOLD
ONTO LOW CHANCE POPS ON WEDNESDAY WITH MODEL SOUNDINGS FAVORING ANY
PRECIP TO FALL IN THE FORM OF LIGHT SNOW. NOT ANTICIPATING ANY
ADDITIONAL LIGHT ACCUMS AT THIS POINT. UPPER TROUGH MOVES AWAY TO
THE EAST WEDNESDAY WITH ANOTHER SURGE OF DEEP SUBSIDENCE ADVECTING
INTO THE REGION AS HIGH PRESSURE REESTABLISHES. SKIES SHOULD CLEAR
QUICKLY SETTING THE STAGE FOR A CHILLY NIGHT.

TEMPS...GENERALLY LEANED TOWARDS COOLER METMOS GUIDANCE THROUGH THE
PERIOD...ESPECIALLY TUESDAY NIGHT AND WEDNESDAY WITH CLOUDS AND
PRECIP. COLDEST NIGHT WILL BE WEDNESDAY NIGHT AS LOWS FALL TO NEAR
20 DEGREES UNDER CLEAR SKIES.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...

QUIET EXTENDED PERIOD FOR THE MOST PART...WITH THE ONLY EXCEPTION
BEING A VERY BROAD UPPER LEVEL TROUGH OVER MUCH OF THE GREAT LAKES
REGION AND MIDWEST ON FRIDAY/FRIDAY NIGHT.  LATEST GFS AND EURO
MODEL RUNS ARE SHOWING MORE MOISTURE WITH AN ASSOCIATED COLD
FRONT...BUT INITIALIZATION NUMBERS ARE STILL TRENDING TOWARD A DRY
FRONTAL PASSAGE ON FRIDAY AFTERNOON/EVENING.  AT THIS TIME...WILL
NOT MAKE ADJUSTMENTS TO INITIALIZATION NUMBERS UNTIL AFTER A FEW
MORE MODEL RUNS COME IN.  OVERNIGHT LOWS WILL BE MORE REPRESENTATIVE
FOR THIS TIME OF YEAR WITH READINGS IN THE UPPER TEENS AND 20S DUE
TO THE CLEAR SKIES.  THE AFOREMENTIONED COLD FRONT WILL LOWER
DAYTIME HIGHS A TAD ON SATURDAY...BUT THEY WILL QUICKLY INCREASE
BACK INTO THE UPPER 30S/LOW 40S BY SUNDAY AND MONDAY.

&&

.AVIATION /DISCUSSION FOR THE 06/18Z TAF ISSUANCE/...

EASTERN EDGE OF STRATUS/FOG DECK NEAR KOKOMO TO KHUF LINE WILL START
ERODING THIS AFTERNOON AND BOTH KHUF AND KLAF TAFS WILL IMPROVE TO
VFR BY LATE AFTERNOON.  FARTHER WEST THAT THIS STRATUS DECK WILL
REMAIN INTACT AND START SPREADING EASTWARD AGAIN DURING THE
OVERNIGHT HOURS.  THE RUC SOUNDING INDICATES THIS OCCURRING
OVERNIGHT AT MOST TAF SITES. BUT THERE IS MORE UNCERTAINTY WHETHER
THIS STRATUS/FOG DECK REACHES KBMG.  FOR NOW WILL PLAY IT THAT
WAY...BUT HAPPENING LATER TONIGHT.  THUS ALL TAFS WILL BECOME IFR OR
LIFR DURING THE OVERNIGHT HOURS.  BUFKIT IS SOMEWHAT NEUTRAL ON
WHETHER THIS WILL BE MOSTLY STRATUS OR FOG.  BUT IN AREAS WHERE
STRATUS ADVECT IN...IT MAY KEEP VISIBILITIES FROM DROPPING TOO LOW.

ON TUESDAY...THERE MAY BE SOME IMPROVEMENT ACROSS THE SOUTHERN HALF
OF OUR REGION. A COLD FRONT WILL MOVE INTO OUR REGION LATE TUESDAY.
WINDS WILL BE WEST OR SOUTHWEST AT 6 TO 8 KNOTS THIS AFTERNOON AND
LESS THAN 5 KNOTS TONIGHT.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
FREEZING FOG ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR INZ021-
028>031-035-036-043-044-051.

&&

$$

SYNOPSIS...RYAN
NEAR TERM...CP
SHORT TERM...RYAN
LONG TERM....TDUD
AVIATION...JH








AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 928 AM EST MON FEB 6 2012

.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW

&&

.SYNOPSIS...

HIGH PRESSURE WILL KEEP DRY MILD WEATHER ACROSS CENTRAL INDIANA
THROUGH TUESDAY. A SERIES OF WEAK UPPER LEVEL DISTURBANCES WILL
BRING THE CHANCE FOR LIGHT PRECIPITATION TUESDAY NIGHT AND
WEDNESDAY. HIGH PRESSURE WILL BRING A RETURN TO DRY WEATHER FOR LATE
WEEK AND INTO THE WEEKEND. THE EXPANSION OF A BROAD UPPER LEVEL
TROUGH WILL SIGNAL A SHIFT TO COLDER TEMPERATURES BY THE WEEKEND.

&&

.NEAR TERM /TODAY/...

6 AM UPDATE...OBS AND WEBCAMS ACROSS THE NORTHERN WABASH VALLEY
SUGGEST THAT FREEZING FOG HAS BECOME MORE WIDESPREAD. HAVE GONE
AHEAD AND INTRODUCED A FREEZING FOG ADVISORY THROUGH 16Z FOR FAR
NORTHWEST FORECAST AREA. ARRIVAL OF BROAD STRATOCU DECK TO THE WEST
MAY SERVE TO MAINTAIN DENSE FOG INTO LATE MORNING.

EARLY MORNING DISCUSSION FOLLOWS.

CLEAR SKIES OVER A MAJORITY OF THE FORECAST AREA THIS MORNING. ONLY
EXCEPTION IS OVER NORTHERN WABASH VALLEY WHERE SHALLOW FREEZING FOG
AND POCKETS OF LOW STRATUS HAVE FORMED EARLY THIS MORNING. TEMPS AT
08Z WERE BELOW FREEZING...FROM THE MID 20S TO LOWER 30S.

MAIN FORECAST ISSUE FOCUSES ON FREEZING FOG THROUGH MID MORNING AND
POTENTIAL IMPACTS FROM DEVELOPING POCKETS OF STRATUS. BROAD AREA OF
STRATUS WITH CEILINGS AT OR BELOW 500FT CONTINUES TO EXPAND SLOWLY
EAST ACROSS NORTHERN ILLINOIS. MOST OF THE SHORT RANGE MODEL
GUIDANCE IS STRUGGLING MIGHTILY WITH THE LOCATION AND EXPANSION OF
THE LARGER STRATUS DECK OVER ILLINOIS...WITH ONLY THE RUC AND TO A
LESSER EXTENT THE 06Z NAM HINTING AT ITS PRESENCE CURRENTLY. HAVE
INTRODUCED AN SPS FOR FREEZING FOG OVER THE ENTIRE FORECAST AREA
THROUGH MID MORNING WITH THE MAIN CONCERN OVER NORTHWEST COUNTIES
AND THE NORTHERN WABASH VALLEY WHERE MANY LOCATIONS ALREADY
REPORTING BELOW 1SM. AT THIS POINT APPEARS DENSE FOG IN NORTHWEST
COUNTIES REMAINS PATCHY BUT SHOULD IT BECOME MORE WIDESPREAD...MAY
NEED TO CONSIDER A FREEZING FOG ADVISORY. WILL CONTINUE TO MONITOR
TRENDS CLOSELY OVER THE NEXT FEW HOURS. SPS SHOULD REMAIN SUFFICIENT
OVER THE REST OF THE FORECAST AREA AS FOG LIKELY TO REMAIN PATCHY.

ONCE VISIBILITIES IMPROVE LATER THIS MORNING...REMAINDER OF THE DAY
SHOULD BE FAIRLY QUIET WITH HIGH PRESSURE ACROSS THE REGION. ONE BIG
CAVEAT WILL BE THE LOCATION AND EXTENT OF THE STRATUS DECK AND JUST
HOW QUICKLY THAT MIXES OUT. AT THIS POINT...APPEARS THE DECK WILL
SPREAD ACROSS FAR NORTHWEST PORTIONS OF THE FORECAST AREA LATER THIS
MORNING. HOWEVER...UNCERTAINTY IS VERY HIGH WITH RESPECT TO HOW MUCH
FURTHER SOUTHEAST THE DECK MAY EXPAND INTO THE FORECAST AREA. HAVE
CHOSEN TO CARRY MOSTLY CLOUDY SKIES OVER NORTHWEST COUNTIES WITH
MOSTLY SUNNY/PARTLY CLOUDY CONDITIONS ELSEWHERE. ADJUSTMENTS WILL BE
MADE ACCORDINGLY THROUGH THE MORNING AS NEEDED.

TEMPS...VERY TRICKY FORECAST AS STRATUS DECK WILL PLAY A MAJOR
FACTOR. HAVE LOWERED TEMPS BY 3-5 DEGREES FROM PREVIOUS FORECAST
OVER THE NORTHERN WABASH VALLEY WHERE CONFIDENCE IS HIGHEST WITH
RESPECT TO CLOUD IMPACTS. SHOULD THE DECK HANG FOR LONGER...THESE
FORECAST HIGHS IN THE LOWER 40S ARE LIKELY TO BE TOO WARM. PLACED
TEMPS NEAR MOS GUIDANCE IN THE MID AND UPPER 40S ELSEWHERE.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...

FORECAST CHALLENGES FOCUS ON PRECIP CHANCES TUESDAY NIGHT AND
WEDNESDAY AS A SERIES OF WEAK UPPER LEVEL DISTURBANCES PASS THROUGH
THE LOWER GREAT LAKES.

HIGH PRESSURE RIDGE WILL BRING ANOTHER TRANQUIL NIGHT WITH CLEAR
SKIES TONIGHT. THE RIDGE SHIFTS EAST TUESDAY WITH MID AND HIGH LEVEL
CLOUDS EXPANDING INTO THE REGION FROM THE NORTHWEST. CHANCES FOR
PRECIPITATION ARE LIKELY TO HOLD OFF UNTIL TUESDAY EVENING AS LEAD
SHORTWAVE ASSOCIATED WITHIN LARGER UPPER TROUGH ROTATES ACROSS THE
REGION. ISENTROPIC LIFT AND OVERALL FORCING REMAIN GENERALLY
WEAK...BUT DOES APPEAR ENOUGH MOISTURE PRESENT FOR LIGHT
PRECIPITATION. WHILE A LIGHT RAIN/SNOW MIX IS POSSIBLE OVER SOUTHERN
COUNTIES TUESDAY EVENING...LOW LEVEL THERMALS AND MODEL SOUNDINGS
SHOW PRECIPITATION AS ALL SNOW AFTER MIDNIGHT AS THE BOUNDARY LAYER
AND NEAR SURFACE TEMPS COOL. SHORTWAVE AXIS SWINGS ACROSS THE
FORECAST AREA BETWEEN 06-12Z WEDNESDAY WITH BEST FORCING ALOFT. THIS
LIKELY TO BE THE TIMEFRAME WHEN LIGHT SNOW IS MOST PREVALENT WITH
HIGHEST POPS. APPEARS THERE COULD BE A FEW TENTHS OF AN INCH
ACCUMULATION BY DAYBREAK WEDNESDAY.

SCATTERED LIGHT SNOW SHOWERS WILL PERSIST WEDNESDAY MORNING WITH A
GRADUAL DIMINISHING OF COVERAGE AS BETTER MOISTURE AND FORCING SHIFT
EAST THROUGH THE DAY. CLOUDS AND A FEW FLURRIES LIKELY TO LINGER
UNTIL THE MAIN UPPER TROUGH PASSES WEDNESDAY AFTERNOON. WILL HOLD
ONTO LOW CHANCE POPS ON WEDNESDAY WITH MODEL SOUNDINGS FAVORING ANY
PRECIP TO FALL IN THE FORM OF LIGHT SNOW. NOT ANTICIPATING ANY
ADDITIONAL LIGHT ACCUMS AT THIS POINT. UPPER TROUGH MOVES AWAY TO
THE EAST WEDNESDAY WITH ANOTHER SURGE OF DEEP SUBSIDENCE ADVECTING
INTO THE REGION AS HIGH PRESSURE REESTABLISHES. SKIES SHOULD CLEAR
QUICKLY SETTING THE STAGE FOR A CHILLY NIGHT.

TEMPS...GENERALLY LEANED TOWARDS COOLER METMOS GUIDANCE THROUGH THE
PERIOD...ESPECIALLY TUESDAY NIGHT AND WEDNESDAY WITH CLOUDS AND
PRECIP. COLDEST NIGHT WILL BE WEDNESDAY NIGHT AS LOWS FALL TO NEAR
20 DEGREES UNDER CLEAR SKIES.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...

QUIET EXTENDED PERIOD FOR THE MOST PART...WITH THE ONLY EXCEPTION
BEING A VERY BROAD UPPER LEVEL TROUGH OVER MUCH OF THE GREAT LAKES
REGION AND MIDWEST ON FRIDAY/FRIDAY NIGHT.  LATEST GFS AND EURO
MODEL RUNS ARE SHOWING MORE MOISTURE WITH AN ASSOCIATED COLD
FRONT...BUT INITIALIZATION NUMBERS ARE STILL TRENDING TOWARD A DRY
FRONTAL PASSAGE ON FRIDAY AFTERNOON/EVENING.  AT THIS TIME...WILL
NOT MAKE ADJUSTMENTS TO INITIALIZATION NUMBERS UNTIL AFTER A FEW
MORE MODEL RUNS COME IN.  OVERNIGHT LOWS WILL BE MORE REPRESENTATIVE
FOR THIS TIME OF YEAR WITH READINGS IN THE UPPER TEENS AND 20S DUE
TO THE CLEAR SKIES.  THE AFOREMENTIONED COLD FRONT WILL LOWER
DAYTIME HIGHS A TAD ON SATURDAY...BUT THEY WILL QUICKLY INCREASE
BACK INTO THE UPPER 30S/LOW 40S BY SUNDAY AND MONDAY.

&&

.AVIATION /DISCUSSION FOR THE 06/15Z KIND TAF UPDATE/...

EASTERN EDGE OF STRATUS/FOG DECK WAS NEAR A KHUF TO KOKOMO LINE. IT
PROBABLY WON`T GET MUCH FARTHER EAST BEFORE IT STARTS ERODING AND IT
WILL DEFINITELY STAY WEST OF KIND.  VISIBILITIES OF 5 TO 6 MILES MAY
STAY AT KIND FOR ANOTHER HOUR. AFTER THAT MOSTLY CLEAR WITH NO
FLIGHT RESTRICTIONS. PREVIOUS AVIATION DISCUSSION FOLLOWS BELOW...

FLYING CONDITIONS VERY SIMILAR TO YESTERDAY MORNING. FOG WILL BE
PROBLEMATIC...ESPECIALLY AT KLAF AND KHUF THROUGH MID MORNING.
PLUS...CURRENT SATELLITE IS SHOWING LOW STRATUS DECK MOVING IN FROM
NORTHERN ILLINOIS RAISING CONCERN OVER POSSIBLE TRAPPING OF DENSE
FOG AT AFOREMENTIONED TAF SITES. SO...WILL KEEP TEMPO OF VLIFR
CONDITIONS AT KLAF AND KHUF THROUGH MID MORNING.

ELSEWHERE...CONDITIONS HAVE BEEN BEHAVING AT KIND AND KBMG WITH
VFR CATEGORY UP TO THIS POINT. AT WORST...COULD SEE SOME BRIEF MVFR
CONDITIONS OVER THE NEXT FEW HOURS AT THESE TAF SITES.

BEYOND MID MORNING...VFR CONDITIONS WILL PREVAIL FOR REMAINDER OF
TAF PERIOD. HIGH CLOUDS WILL INCREASE AT TAIL END OF TAF PERIOD AS
THE NEXT DISTURBANCE APPROACHES AREA...BUT THIS WILL HAVE NO
IMPACT ON FLIGHT OPERATIONS.

WINDS WILL BE WESTERLY AT 4 TO 8 KTS FOR THE MAJORITY OF TAF
PERIOD...AND WILL THEN START VEERING TO THE NORTHWEST TOMORROW
MORNING. SUSTAINED WIND SPEEDS WILL INCREASE TO 5 TO 10 KTS.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
FREEZING FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR INZ021-
028-029-035-043.

&&

$$

SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....TDUD
AVIATION...TDUD/JH










AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 647 AM EST MON FEB 6 2012

.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW

&&

.SYNOPSIS...

HIGH PRESSURE WILL KEEP DRY MILD WEATHER ACROSS CENTRAL INDIANA
THROUGH TUESDAY. A SERIES OF WEAK UPPER LEVEL DISTURBANCES WILL
BRING THE CHANCE FOR LIGHT PRECIPITATION TUESDAY NIGHT AND
WEDNESDAY. HIGH PRESSURE WILL BRING A RETURN TO DRY WEATHER FOR LATE
WEEK AND INTO THE WEEKEND. THE EXPANSION OF A BROAD UPPER LEVEL
TROUGH WILL SIGNAL A SHIFT TO COLDER TEMPERATURES BY THE WEEKEND.

&&

.NEAR TERM /TODAY/...

6 AM UPDATE...OBS AND WEBCAMS ACROSS THE NORTHERN WABASH VALLEY
SUGGEST THAT FREEZING FOG HAS BECOME MORE WIDESPREAD. HAVE GONE
AHEAD AND INTRODUCED A FREEZING FOG ADVISORY THROUGH 16Z FOR FAR
NORTHWEST FORECAST AREA. ARRIVAL OF BROAD STRATOCU DECK TO THE WEST
MAY SERVE TO MAINTAIN DENSE FOG INTO LATE MORNING.

EARLY MORNING DISCUSSION FOLLOWS.

CLEAR SKIES OVER A MAJORITY OF THE FORECAST AREA THIS MORNING. ONLY
EXCEPTION IS OVER NORTHERN WABASH VALLEY WHERE SHALLOW FREEZING FOG
AND POCKETS OF LOW STRATUS HAVE FORMED EARLY THIS MORNING. TEMPS AT
08Z WERE BELOW FREEZING...FROM THE MID 20S TO LOWER 30S.

MAIN FORECAST ISSUE FOCUSES ON FREEZING FOG THROUGH MID MORNING AND
POTENTIAL IMPACTS FROM DEVELOPING POCKETS OF STRATUS. BROAD AREA OF
STRATUS WITH CEILINGS AT OR BELOW 500FT CONTINUES TO EXPAND SLOWLY
EAST ACROSS NORTHERN ILLINOIS. MOST OF THE SHORT RANGE MODEL
GUIDANCE IS STRUGGLING MIGHTILY WITH THE LOCATION AND EXPANSION OF
THE LARGER STRATUS DECK OVER ILLINOIS...WITH ONLY THE RUC AND TO A
LESSER EXTENT THE 06Z NAM HINTING AT ITS PRESENCE CURRENTLY. HAVE
INTRODUCED AN SPS FOR FREEZING FOG OVER THE ENTIRE FORECAST AREA
THROUGH MID MORNING WITH THE MAIN CONCERN OVER NORTHWEST COUNTIES
AND THE NORTHERN WABASH VALLEY WHERE MANY LOCATIONS ALREADY
REPORTING BELOW 1SM. AT THIS POINT APPEARS DENSE FOG IN NORTHWEST
COUNTIES REMAINS PATCHY BUT SHOULD IT BECOME MORE WIDESPREAD...MAY
NEED TO CONSIDER A FREEZING FOG ADVISORY. WILL CONTINUE TO MONITOR
TRENDS CLOSELY OVER THE NEXT FEW HOURS. SPS SHOULD REMAIN SUFFICIENT
OVER THE REST OF THE FORECAST AREA AS FOG LIKELY TO REMAIN PATCHY.

ONCE VISIBILITIES IMPROVE LATER THIS MORNING...REMAINDER OF THE DAY
SHOULD BE FAIRLY QUIET WITH HIGH PRESSURE ACROSS THE REGION. ONE BIG
CAVEAT WILL BE THE LOCATION AND EXTENT OF THE STRATUS DECK AND JUST
HOW QUICKLY THAT MIXES OUT. AT THIS POINT...APPEARS THE DECK WILL
SPREAD ACROSS FAR NORTHWEST PORTIONS OF THE FORECAST AREA LATER THIS
MORNING. HOWEVER...UNCERTAINTY IS VERY HIGH WITH RESPECT TO HOW MUCH
FURTHER SOUTHEAST THE DECK MAY EXPAND INTO THE FORECAST AREA. HAVE
CHOSEN TO CARRY MOSTLY CLOUDY SKIES OVER NORTHWEST COUNTIES WITH
MOSTLY SUNNY/PARTLY CLOUDY CONDITIONS ELSEWHERE. ADJUSTMENTS WILL BE
MADE ACCORDINGLY THROUGH THE MORNING AS NEEDED.

TEMPS...VERY TRICKY FORECAST AS STRATUS DECK WILL PLAY A MAJOR
FACTOR. HAVE LOWERED TEMPS BY 3-5 DEGREES FROM PREVIOUS FORECAST
OVER THE NORTHERN WABASH VALLEY WHERE CONFIDENCE IS HIGHEST WITH
RESPECT TO CLOUD IMPACTS. SHOULD THE DECK HANG FOR LONGER...THESE
FORECAST HIGHS IN THE LOWER 40S ARE LIKELY TO BE TOO WARM. PLACED
TEMPS NEAR MOS GUIDANCE IN THE MID AND UPPER 40S ELSEWHERE.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...

FORECAST CHALLENGES FOCUS ON PRECIP CHANCES TUESDAY NIGHT AND
WEDNESDAY AS A SERIES OF WEAK UPPER LEVEL DISTURBANCES PASS THROUGH
THE LOWER GREAT LAKES.

HIGH PRESSURE RIDGE WILL BRING ANOTHER TRANQUIL NIGHT WITH CLEAR
SKIES TONIGHT. THE RIDGE SHIFTS EAST TUESDAY WITH MID AND HIGH LEVEL
CLOUDS EXPANDING INTO THE REGION FROM THE NORTHWEST. CHANCES FOR
PRECIPITATION ARE LIKELY TO HOLD OFF UNTIL TUESDAY EVENING AS LEAD
SHORTWAVE ASSOCIATED WITHIN LARGER UPPER TROUGH ROTATES ACROSS THE
REGION. ISENTROPIC LIFT AND OVERALL FORCING REMAIN GENERALLY
WEAK...BUT DOES APPEAR ENOUGH MOISTURE PRESENT FOR LIGHT
PRECIPITATION. WHILE A LIGHT RAIN/SNOW MIX IS POSSIBLE OVER SOUTHERN
COUNTIES TUESDAY EVENING...LOW LEVEL THERMALS AND MODEL SOUNDINGS
SHOW PRECIPITATION AS ALL SNOW AFTER MIDNIGHT AS THE BOUNDARY LAYER
AND NEAR SURFACE TEMPS COOL. SHORTWAVE AXIS SWINGS ACROSS THE
FORECAST AREA BETWEEN 06-12Z WEDNESDAY WITH BEST FORCING ALOFT. THIS
LIKELY TO BE THE TIMEFRAME WHEN LIGHT SNOW IS MOST PREVALENT WITH
HIGHEST POPS. APPEARS THERE COULD BE A FEW TENTHS OF AN INCH
ACCUMULATION BY DAYBREAK WEDNESDAY.

SCATTERED LIGHT SNOW SHOWERS WILL PERSIST WEDNESDAY MORNING WITH A
GRADUAL DIMINISHING OF COVERAGE AS BETTER MOISTURE AND FORCING SHIFT
EAST THROUGH THE DAY. CLOUDS AND A FEW FLURRIES LIKELY TO LINGER
UNTIL THE MAIN UPPER TROUGH PASSES WEDNESDAY AFTERNOON. WILL HOLD
ONTO LOW CHANCE POPS ON WEDNESDAY WITH MODEL SOUNDINGS FAVORING ANY
PRECIP TO FALL IN THE FORM OF LIGHT SNOW. NOT ANTICIPATING ANY
ADDITIONAL LIGHT ACCUMS AT THIS POINT. UPPER TROUGH MOVES AWAY TO
THE EAST WEDNESDAY WITH ANOTHER SURGE OF DEEP SUBSIDENCE ADVECTING
INTO THE REGION AS HIGH PRESSURE REESTABLISHES. SKIES SHOULD CLEAR
QUICKLY SETTING THE STAGE FOR A CHILLY NIGHT.

TEMPS...GENERALLY LEANED TOWARDS COOLER METMOS GUIDANCE THROUGH THE
PERIOD...ESPECIALLY TUESDAY NIGHT AND WEDNESDAY WITH CLOUDS AND
PRECIP. COLDEST NIGHT WILL BE WEDNESDAY NIGHT AS LOWS FALL TO NEAR
20 DEGREES UNDER CLEAR SKIES.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...

QUIET EXTENDED PERIOD FOR THE MOST PART...WITH THE ONLY EXCEPTION
BEING A VERY BROAD UPPER LEVEL TROUGH OVER MUCH OF THE GREAT LAKES
REGION AND MIDWEST ON FRIDAY/FRIDAY NIGHT.  LATEST GFS AND EURO
MODEL RUNS ARE SHOWING MORE MOISTURE WITH AN ASSOCIATED COLD
FRONT...BUT INITIALIZATION NUMBERS ARE STILL TRENDING TOWARD A DRY
FRONTAL PASSAGE ON FRIDAY AFTERNOON/EVENING.  AT THIS TIME...WILL
NOT MAKE ADJUSTMENTS TO INITIALIZATION NUMBERS UNTIL AFTER A FEW MORE
MODEL RUNS COME IN.  OVERNIGHT LOWS WILL BE MORE REPRESENTATIVE FOR
THIS TIME OF YEAR WITH READINGS IN THE UPPER TEENS AND 20S DUE TO
THE CLEAR SKIES.  THE AFOREMENTIONED COLD FRONT WILL LOWER DAYTIME
HIGHS A TAD ON SATURDAY...BUT THEY WILL QUICKLY INCREASE BACK INTO
THE UPPER 30S/LOW 40S BY SUNDAY AND MONDAY.

&&

.AVIATION /DISCUSSION FOR THE 06/12Z TAF ISSUANCE/...

FLYING CONDITIONS VERY SIMILAR TO YESTERDAY MORNING. FOG WILL BE
PROBLEMATIC...ESPECIALLY AT KLAF AND KHUF THROUGH MID MORNING.
PLUS...CURRENT SATELLITE IS SHOWING LOW STRATUS DECK MOVING IN
FROM NORTHERN ILLINOIS RAISING CONCERN OVER POSSIBLE TRAPPING OF
DENSE FOG AT AFOREMENTIONED TAF SITES. SO...WILL KEEP TEMPO OF
VLIFR CONDITIONS AT KLAF AND KHUF THROUGH MID MORNING.

ELSEWHERE...CONDITIONS HAVE BEEN BEHAVING AT KIND AND KBMG WITH
VFR CATEGORY UP TO THIS POINT. AT WORST...COULD SEE SOME BRIEF MVFR
CONDITIONS OVER THE NEXT FEW HOURS AT THESE TAF SITES.

BEYOND MID MORNING...VFR CONDITIONS WILL PREVAIL FOR REMAINDER OF
TAF PERIOD. HIGH CLOUDS WILL INCREASE AT TAIL END OF TAF PERIOD AS
THE NEXT DISTURBANCE APPROACHES AREA...BUT THIS WILL HAVE NO
IMPACT ON FLIGHT OPERATIONS.

WINDS WILL BE WESTERLY AT 4 TO 8 KTS FOR THE MAJORITY OF TAF
PERIOD...AND WILL THEN START VEERING TO THE NORTHWEST TOMORROW
MORNING. SUSTAINED WIND SPEEDS WILL INCREASE TO 5 TO 10 KTS.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
FREEZING FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR INZ021-
028-029-035-043.

&&

$$

SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....TDUD
AVIATION...TDUD







AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 617 AM EST MON FEB 6 2012

.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...

HIGH PRESSURE WILL KEEP DRY MILD WEATHER ACROSS CENTRAL INDIANA
THROUGH TUESDAY. A SERIES OF WEAK UPPER LEVEL DISTURBANCES WILL
BRING THE CHANCE FOR LIGHT PRECIPITATION TUESDAY NIGHT AND
WEDNESDAY. HIGH PRESSURE WILL BRING A RETURN TO DRY WEATHER FOR LATE
WEEK AND INTO THE WEEKEND. THE EXPANSION OF A BROAD UPPER LEVEL
TROUGH WILL SIGNAL A SHIFT TO COLDER TEMPERATURES BY THE WEEKEND.

&&

.NEAR TERM /TODAY/...

6 AM UPDATE...OBS AND WEBCAMS ACROSS THE NORTHERN WABASH VALLEY
SUGGEST THAT FREEZING FOG HAS BECOME MORE WIDESPREAD. HAVE GONE
AHEAD AND INTRODUCED A FREEZING FOG ADVISORY THROUGH 16Z FOR FAR
NORTHWEST FORECAST AREA. ARRIVAL OF BROAD STRATOCU DECK TO THE WEST
MAY SERVE TO MAINTAIN DENSE FOG INTO LATE MORNING.

EARLY MORNING DISCUSSION FOLLOWS.

CLEAR SKIES OVER A MAJORITY OF THE FORECAST AREA THIS MORNING. ONLY
EXCEPTION IS OVER NORTHERN WABASH VALLEY WHERE SHALLOW FREEZING FOG
AND POCKETS OF LOW STRATUS HAVE FORMED EARLY THIS MORNING. TEMPS AT
08Z WERE BELOW FREEZING...FROM THE MID 20S TO LOWER 30S.

MAIN FORECAST ISSUE FOCUSES ON FREEZING FOG THROUGH MID MORNING AND
POTENTIAL IMPACTS FROM DEVELOPING POCKETS OF STRATUS. BROAD AREA OF
STRATUS WITH CEILINGS AT OR BELOW 500FT CONTINUES TO EXPAND SLOWLY
EAST ACROSS NORTHERN ILLINOIS. MOST OF THE SHORT RANGE MODEL
GUIDANCE IS STRUGGLING MIGHTILY WITH THE LOCATION AND EXPANSION OF
THE LARGER STRATUS DECK OVER ILLINOIS...WITH ONLY THE RUC AND TO A
LESSER EXTENT THE 06Z NAM HINTING AT ITS PRESENCE CURRENTLY. HAVE
INTRODUCED AN SPS FOR FREEZING FOG OVER THE ENTIRE FORECAST AREA
THROUGH MID MORNING WITH THE MAIN CONCERN OVER NORTHWEST COUNTIES
AND THE NORTHERN WABASH VALLEY WHERE MANY LOCATIONS ALREADY
REPORTING BELOW 1SM. AT THIS POINT APPEARS DENSE FOG IN NORTHWEST
COUNTIES REMAINS PATCHY BUT SHOULD IT BECOME MORE WIDESPREAD...MAY
NEED TO CONSIDER A FREEZING FOG ADVISORY. WILL CONTINUE TO MONITOR
TRENDS CLOSELY OVER THE NEXT FEW HOURS. SPS SHOULD REMAIN SUFFICIENT
OVER THE REST OF THE FORECAST AREA AS FOG LIKELY TO REMAIN PATCHY.

ONCE VISIBILITIES IMPROVE LATER THIS MORNING...REMAINDER OF THE DAY
SHOULD BE FAIRLY QUIET WITH HIGH PRESSURE ACROSS THE REGION. ONE BIG
CAVEAT WILL BE THE LOCATION AND EXTENT OF THE STRATUS DECK AND JUST
HOW QUICKLY THAT MIXES OUT. AT THIS POINT...APPEARS THE DECK WILL
SPREAD ACROSS FAR NORTHWEST PORTIONS OF THE FORECAST AREA LATER THIS
MORNING. HOWEVER...UNCERTAINTY IS VERY HIGH WITH RESPECT TO HOW MUCH
FURTHER SOUTHEAST THE DECK MAY EXPAND INTO THE FORECAST AREA. HAVE
CHOSEN TO CARRY MOSTLY CLOUDY SKIES OVER NORTHWEST COUNTIES WITH
MOSTLY SUNNY/PARTLY CLOUDY CONDITIONS ELSEWHERE. ADJUSTMENTS WILL BE
MADE ACCORDINGLY THROUGH THE MORNING AS NEEDED.

TEMPS...VERY TRICKY FORECAST AS STRATUS DECK WILL PLAY A MAJOR
FACTOR. HAVE LOWERED TEMPS BY 3-5 DEGREES FROM PREVIOUS FORECAST
OVER THE NORTHERN WABASH VALLEY WHERE CONFIDENCE IS HIGHEST WITH
RESPECT TO CLOUD IMPACTS. SHOULD THE DECK HANG FOR LONGER...THESE
FORECAST HIGHS IN THE LOWER 40S ARE LIKELY TO BE TOO WARM. PLACED
TEMPS NEAR MOS GUIDANCE IN THE MID AND UPPER 40S ELSEWHERE.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...

FORECAST CHALLENGES FOCUS ON PRECIP CHANCES TUESDAY NIGHT AND
WEDNESDAY AS A SERIES OF WEAK UPPER LEVEL DISTURBANCES PASS THROUGH
THE LOWER GREAT LAKES.

HIGH PRESSURE RIDGE WILL BRING ANOTHER TRANQUIL NIGHT WITH CLEAR
SKIES TONIGHT. THE RIDGE SHIFTS EAST TUESDAY WITH MID AND HIGH LEVEL
CLOUDS EXPANDING INTO THE REGION FROM THE NORTHWEST. CHANCES FOR
PRECIPITATION ARE LIKELY TO HOLD OFF UNTIL TUESDAY EVENING AS LEAD
SHORTWAVE ASSOCIATED WITHIN LARGER UPPER TROUGH ROTATES ACROSS THE
REGION. ISENTROPIC LIFT AND OVERALL FORCING REMAIN GENERALLY
WEAK...BUT DOES APPEAR ENOUGH MOISTURE PRESENT FOR LIGHT
PRECIPITATION. WHILE A LIGHT RAIN/SNOW MIX IS POSSIBLE OVER SOUTHERN
COUNTIES TUESDAY EVENING...LOW LEVEL THERMALS AND MODEL SOUNDINGS
SHOW PRECIPITATION AS ALL SNOW AFTER MIDNIGHT AS THE BOUNDARY LAYER
AND NEAR SURFACE TEMPS COOL. SHORTWAVE AXIS SWINGS ACROSS THE
FORECAST AREA BETWEEN 06-12Z WEDNESDAY WITH BEST FORCING ALOFT. THIS
LIKELY TO BE THE TIMEFRAME WHEN LIGHT SNOW IS MOST PREVALENT WITH
HIGHEST POPS. APPEARS THERE COULD BE A FEW TENTHS OF AN INCH
ACCUMULATION BY DAYBREAK WEDNESDAY.

SCATTERED LIGHT SNOW SHOWERS WILL PERSIST WEDNESDAY MORNING WITH A
GRADUAL DIMINISHING OF COVERAGE AS BETTER MOISTURE AND FORCING SHIFT
EAST THROUGH THE DAY. CLOUDS AND A FEW FLURRIES LIKELY TO LINGER
UNTIL THE MAIN UPPER TROUGH PASSES WEDNESDAY AFTERNOON. WILL HOLD
ONTO LOW CHANCE POPS ON WEDNESDAY WITH MODEL SOUNDINGS FAVORING ANY
PRECIP TO FALL IN THE FORM OF LIGHT SNOW. NOT ANTICIPATING ANY
ADDITIONAL LIGHT ACCUMS AT THIS POINT. UPPER TROUGH MOVES AWAY TO
THE EAST WEDNESDAY WITH ANOTHER SURGE OF DEEP SUBSIDENCE ADVECTING
INTO THE REGION AS HIGH PRESSURE REESTABLISHES. SKIES SHOULD CLEAR
QUICKLY SETTING THE STAGE FOR A CHILLY NIGHT.

TEMPS...GENERALLY LEANED TOWARDS COOLER METMOS GUIDANCE THROUGH THE
PERIOD...ESPECIALLY TUESDAY NIGHT AND WEDNESDAY WITH CLOUDS AND
PRECIP. COLDEST NIGHT WILL BE WEDNESDAY NIGHT AS LOWS FALL TO NEAR
20 DEGREES UNDER CLEAR SKIES.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...

QUIET EXTENDED PERIOD FOR THE MOST PART...WITH THE ONLY EXCEPTION
BEING A VERY BROAD UPPER LEVEL TROUGH OVER MUCH OF THE GREAT LAKES
REGION AND MIDWEST ON FRIDAY/FRIDAY NIGHT.  LATEST GFS AND EURO
MODEL RUNS ARE SHOWING MORE MOISTURE WITH AN ASSOCIATED COLD
FRONT...BUT INITIALIZATION NUMBERS ARE STILL TRENDING TOWARD A DRY
FRONTAL PASSAGE ON FRIDAY AFTERNOON/EVENING.  AT THIS TIME...WILL
NOT MAKE ADJUSTMENTS TO INITIALIZATION NUMBERS UNTIL AFTER A FEW MORE
MODEL RUNS COME IN.  OVERNIGHT LOWS WILL BE MORE REPRESENTATIVE FOR
THIS TIME OF YEAR WITH READINGS IN THE UPPER TEENS AND 20S DUE TO
THE CLEAR SKIES.  THE AFOREMENTIONED COLD FRONT WILL LOWER DAYTIME
HIGHS A TAD ON SATURDAY...BUT THEY WILL QUICKLY INCREASE BACK INTO
THE UPPER 30S/LOW 40S BY SUNDAY AND MONDAY.

&&

.AVIATION /DISCUSSION FOR THE 06/09Z TAF UPDATE/...

UPDATE...

FOG IS PROVING TO BE PROBLEMATIC AT KLAF AND KHUF WITH
VISIBILITIES IN THE LIFR/IFR CATEGORIES. ELSEWHERE...CONDITIONS
ARE HOLDING UP AT KIND AND KBMG...SO TEMPO MVFR THROUGH MON 13Z
STILL LOOKS REASONABLE AT THOSE SITES.

PREVIOUS DISCUSSION...
MAINLY VFR THROUGH THE PERIOD...WITH A PERIOD OF MVFR POSSIBLE NEAR
DAYBREAK TOMORROW.

HIGH PRESSURE HAS BUILT IN...ERODING ANY LEFTOVER CLOUD...AND
ALLOWING SIGNIFICANT DRYING AT THE SURFACE THROUGH A LIGHT NORTHERLY
SURFACE FLOW AND AMPLE SUNSHINE WITH THE SUPERB WEATHER YESTERDAY
AFTERNOON. ALTHOUGH WINDS WILL BE CALM TO LIGHT AND SKIES WILL BE
CLEAR OVERNIGHT...DO NOT EXPECT SIGNIFICANT FOG TO FORM. WILL
INCLUDE SOME HIGH END MVFR FOG FOR A FEW HOURS NEAR DAYBREAK AT ALL
SITES IN TEMPO GROUPS. NAM/RUC SOUNDINGS SHOW DECENT SATURATION NEAR
THE SURFACE...GFS/SREF SOUNDINGS DO NOT. NAM SOUNDING IS MOST
FAVORABLE...BUT ITS 00Z MOS DOES NOT BRING ANY RESTRICTIONS IN.

WINDS WILL BE CALM TO LIGHT OVERNIGHT...BECOMING WEST/SOUTHWESTERLY
TOMORROW BUT REMAINING BELOW 10KT. MAY SEE INFREQUENT GUSTS INTO THE
LOW TEENS BUT SURFACE PRESSURE GRADIENT APPEARS FAIRLY WEAK...SO
WILL NOT INCLUDE ANY MENTION AT THIS TIME.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....TDUD
AVIATION...NIELD/TDUD










AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 359 AM EST MON FEB 6 2012

.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM AND LONG TERM SECTIONS HAVE
BEEN UPDATED BELOW.

&&

.SYNOPSIS...

HIGH PRESSURE WILL KEEP DRY MILD WEATHER ACROSS CENTRAL INDIANA
THROUGH TUESDAY. A SERIES OF WEAK UPPER LEVEL DISTURBANCES WILL
BRING THE CHANCE FOR LIGHT PRECIPITATION TUESDAY NIGHT AND
WEDNESDAY. HIGH PRESSURE WILL BRING A RETURN TO DRY WEATHER FOR LATE
WEEK AND INTO THE WEEKEND. THE EXPANSION OF A BROAD UPPER LEVEL
TROUGH WILL SIGNAL A SHIFT TO COLDER TEMPERATURES BY THE WEEKEND.

&&

.NEAR TERM /TODAY/...

CLEAR SKIES OVER A MAJORITY OF THE FORECAST AREA THIS MORNING. ONLY
EXCEPTION IS OVER NORTHERN WABASH VALLEY WHERE SHALLOW FREEZING FOG
AND POCKETS OF LOW STRATUS HAVE FORMED EARLY THIS MORNING. TEMPS AT
08Z WERE BELOW FREEZING...FROM THE MID 20S TO LOWER 30S.

MAIN FORECAST ISSUE FOCUSES ON FREEZING FOG THROUGH MID MORNING AND
POTENTIAL IMPACTS FROM DEVELOPING POCKETS OF STRATUS. BROAD AREA OF
STRATUS WITH CEILINGS AT OR BELOW 500FT CONTINUES TO EXPAND SLOWLY
EAST ACROSS NORTHERN ILLINOIS. MOST OF THE SHORT RANGE MODEL
GUIDANCE IS STRUGGLING MIGHTILY WITH THE LOCATION AND EXPANSION OF
THE LARGER STRATUS DECK OVER ILLINOIS...WITH ONLY THE RUC AND TO A
LESSER EXTENT THE 06Z NAM HINTING AT ITS PRESENCE CURRENTLY. HAVE
INTRODUCED AN SPS FOR FREEZING FOG OVER THE ENTIRE FORECAST AREA
THROUGH MID MORNING WITH THE MAIN CONCERN OVER NORTHWEST COUNTIES
AND THE NORTHERN WABASH VALLEY WHERE MANY LOCATIONS ALREADY
REPORTING BELOW 1SM. AT THIS POINT APPEARS DENSE FOG IN NORTHWEST
COUNTIES REMAINS PATCHY BUT SHOULD IT BECOME MORE WIDESPREAD...MAY
NEED TO CONSIDER A FREEZING FOG ADVISORY. WILL CONTINUE TO MONITOR
TRENDS CLOSELY OVER THE NEXT FEW HOURS. SPS SHOULD REMAIN SUFFICIENT
OVER THE REST OF THE FORECAST AREA AS FOG LIKELY TO REMAIN PATCHY.

ONCE VISIBILITIES IMPROVE LATER THIS MORNING...REMAINDER OF THE DAY
SHOULD BE FAIRLY QUIET WITH HIGH PRESSURE ACROSS THE REGION. ONE BIG
CAVEAT WILL BE THE LOCATION AND EXTENT OF THE STRATUS DECK AND JUST
HOW QUICKLY THAT MIXES OUT. AT THIS POINT...APPEARS THE DECK WILL
SPREAD ACROSS FAR NORTHWEST PORTIONS OF THE FORECAST AREA LATER THIS
MORNING. HOWEVER...UNCERTAINTY IS VERY HIGH WITH RESPECT TO HOW MUCH
FURTHER SOUTHEAST THE DECK MAY EXPAND INTO THE FORECAST AREA. HAVE
CHOSEN TO CARRY MOSTLY CLOUDY SKIES OVER NORTHWEST COUNTIES WITH
MOSTLY SUNNY/PARTLY CLOUDY CONDITIONS ELSEWHERE. ADJUSTMENTS WILL BE
MADE ACCORDINGLY THROUGH THE MORNING AS NEEDED.

TEMPS...VERY TRICKY FORECAST AS STRATUS DECK WILL PLAY A MAJOR
FACTOR. HAVE LOWERED TEMPS BY 3-5 DEGREES FROM PREVIOUS FORECAST
OVER THE NORTHERN WABASH VALLEY WHERE CONFIDENCE IS HIGHEST WITH
RESPECT TO CLOUD IMPACTS. SHOULD THE DECK HANG FOR LONGER...THESE
FORECAST HIGHS IN THE LOWER 40S ARE LIKELY TO BE TOO WARM. PLACED
TEMPS NEAR MOS GUIDANCE IN THE MID AND UPPER 40S ELSEWHERE.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...

FORECAST CHALLENGES FOCUS ON PRECIP CHANCES TUESDAY NIGHT AND
WEDNESDAY AS A SERIES OF WEAK UPPER LEVEL DISTURBANCES PASS THROUGH
THE LOWER GREAT LAKES.

HIGH PRESSURE RIDGE WILL BRING ANOTHER TRANQUIL NIGHT WITH CLEAR
SKIES TONIGHT. THE RIDGE SHIFTS EAST TUESDAY WITH MID AND HIGH LEVEL
CLOUDS EXPANDING INTO THE REGION FROM THE NORTHWEST. CHANCES FOR
PRECIPITATION ARE LIKELY TO HOLD OFF UNTIL TUESDAY EVENING AS LEAD
SHORTWAVE ASSOCIATED WITHIN LARGER UPPER TROUGH ROTATES ACROSS THE
REGION. ISENTROPIC LIFT AND OVERALL FORCING REMAIN GENERALLY
WEAK...BUT DOES APPEAR ENOUGH MOISTURE PRESENT FOR LIGHT
PRECIPITATION. WHILE A LIGHT RAIN/SNOW MIX IS POSSIBLE OVER SOUTHERN
COUNTIES TUESDAY EVENING...LOW LEVEL THERMALS AND MODEL SOUNDINGS
SHOW PRECIPITATION AS ALL SNOW AFTER MIDNIGHT AS THE BOUNDARY LAYER
AND NEAR SURFACE TEMPS COOL. SHORTWAVE AXIS SWINGS ACROSS THE
FORECAST AREA BETWEEN 06-12Z WEDNESDAY WITH BEST FORCING ALOFT. THIS
LIKELY TO BE THE TIMEFRAME WHEN LIGHT SNOW IS MOST PREVALENT WITH
HIGHEST POPS. APPEARS THERE COULD BE A FEW TENTHS OF AN INCH
ACCUMULATION BY DAYBREAK WEDNESDAY.

SCATTERED LIGHT SNOW SHOWERS WILL PERSIST WEDNESDAY MORNING WITH A
GRADUAL DIMINISHING OF COVERAGE AS BETTER MOISTURE AND FORCING SHIFT
EAST THROUGH THE DAY. CLOUDS AND A FEW FLURRIES LIKELY TO LINGER
UNTIL THE MAIN UPPER TROUGH PASSES WEDNESDAY AFTERNOON. WILL HOLD
ONTO LOW CHANCE POPS ON WEDNESDAY WITH MODEL SOUNDINGS FAVORING ANY
PRECIP TO FALL IN THE FORM OF LIGHT SNOW. NOT ANTICIPATING ANY
ADDITIONAL LIGHT ACCUMS AT THIS POINT. UPPER TROUGH MOVES AWAY TO
THE EAST WEDNESDAY WITH ANOTHER SURGE OF DEEP SUBSIDENCE ADVECTING
INTO THE REGION AS HIGH PRESSURE REESTABLISHES. SKIES SHOULD CLEAR
QUICKLY SETTING THE STAGE FOR A CHILLY NIGHT.

TEMPS...GENERALLY LEANED TOWARDS COOLER METMOS GUIDANCE THROUGH THE
PERIOD...ESPECIALLY TUESDAY NIGHT AND WEDNESDAY WITH CLOUDS AND
PRECIP. COLDEST NIGHT WILL BE WEDNESDAY NIGHT AS LOWS FALL TO NEAR
20 DEGREES UNDER CLEAR SKIES.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...

QUIET EXTENDED PERIOD FOR THE MOST PART...WITH THE ONLY EXCEPTION
BEING A VERY BROAD UPPER LEVEL TROUGH OVER MUCH OF THE GREAT LAKES
REGION AND MIDWEST ON FRIDAY/FRIDAY NIGHT.  LATEST GFS AND EURO
MODEL RUNS ARE SHOWING MORE MOISTURE WITH AN ASSOCIATED COLD
FRONT...BUT INITIALIZATION NUMBERS ARE STILL TRENDING TOWARD A DRY
FRONTAL PASSAGE ON FRIDAY AFTERNOON/EVENING.  AT THIS TIME...WILL
NOT MAKE ADJUSTMENTS TO INITIALIZATION NUMBERS UNTIL AFTER A FEW MORE
MODEL RUNS COME IN.  OVERNIGHT LOWS WILL BE MORE REPRESENTATIVE FOR
THIS TIME OF YEAR WITH READINGS IN THE UPPER TEENS AND 20S DUE TO
THE CLEAR SKIES.  THE AFOREMENTIONED COLD FRONT WILL LOWER DAYTIME
HIGHS A TAD ON SATURDAY...BUT THEY WILL QUICKLY INCREASE BACK INTO
THE UPPER 30S/LOW 40S BY SUNDAY AND MONDAY.

&&

.AVIATION /DISCUSSION FOR THE 06/09Z TAF UPDATE/...

UPDATE...

FOG IS PROVING TO BE PROBLEMATIC AT KLAF AND KHUF WITH
VISIBILITIES IN THE LIFR/IFR CATEGORIES. ELSEWHERE...CONDITIONS
ARE HOLDING UP AT KIND AND KBMG...SO TEMPO MVFR THROUGH MON 13Z
STILL LOOKS REASONABLE AT THOSE SITES.

PREVIOUS DISCUSSION...
MAINLY VFR THROUGH THE PERIOD...WITH A PERIOD OF MVFR POSSIBLE NEAR
DAYBREAK TOMORROW.

HIGH PRESSURE HAS BUILT IN...ERODING ANY LEFTOVER CLOUD...AND
ALLOWING SIGNIFICANT DRYING AT THE SURFACE THROUGH A LIGHT NORTHERLY
SURFACE FLOW AND AMPLE SUNSHINE WITH THE SUPERB WEATHER YESTERDAY
AFTERNOON. ALTHOUGH WINDS WILL BE CALM TO LIGHT AND SKIES WILL BE
CLEAR OVERNIGHT...DO NOT EXPECT SIGNIFICANT FOG TO FORM. WILL
INCLUDE SOME HIGH END MVFR FOG FOR A FEW HOURS NEAR DAYBREAK AT ALL
SITES IN TEMPO GROUPS. NAM/RUC SOUNDINGS SHOW DECENT SATURATION NEAR
THE SURFACE...GFS/SREF SOUNDINGS DO NOT. NAM SOUNDING IS MOST
FAVORABLE...BUT ITS 00Z MOS DOES NOT BRING ANY RESTRICTIONS IN.

WINDS WILL BE CALM TO LIGHT OVERNIGHT...BECOMING WEST/SOUTHWESTERLY
TOMORROW BUT REMAINING BELOW 10KT. MAY SEE INFREQUENT GUSTS INTO THE
LOW TEENS BUT SURFACE PRESSURE GRADIENT APPEARS FAIRLY WEAK...SO
WILL NOT INCLUDE ANY MENTION AT THIS TIME.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....TDUD
AVIATION...NIELD/TDUD







AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 345 AM EST MON FEB 6 2012

.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW

&&

.SYNOPSIS...

HIGH PRESSURE IS GOING TO COVER INDIANA THROUGH MONDAY. A SERIES
OF WEAK DISTURBANCES WILL PASS OVERHEAD LATER THIS WEEK.
HOWEVER...HIGH PRESSURE WILL BE THE RULE AT THE SURFACE SO
PRECIPITATION CHANCES SHOULD STAY SMALL.

&&

.NEAR TERM /TONIGHT/...

MAIN ISSUES ARE TEMPERATURES AND FOG AS MODELS AND OBS ALL SUPPORT
CLEAR TONIGHT.

AT 01Z WINDS IN OBSERVATIONS INDICATED A WEAK SURFACE RIDGE TO OUR
WEST. RUC SAYS THIS WILL WORK EASTWARD AND ALMOST COMPLETELY KILL
OUR WINDS LATE TONIGHT. WITH THAT AND OUR CURRENT TEMPERATURES
ROUGHLY 3 DEGREES BELOW THE HOURLY GRIDS...I AM GOING TO DROP
MINS TONIGHT ABOUT A CATEGORY.

CLEAR WITH LIGHT WIND FAVORS FOG TONIGHT. BUFKIT SHOWS MOISTURE
DECREASING RAPIDLY WITH HEIGHT...A NEGATIVE. WITH OFFSETTING
FACTORS I WILL KEEP FOG IN THE FORECAST BUT WONT MENTION DENSE.
GIVEN DAMP GROUND WE MIGHT GET FOG OUTSIDE THE COMMON LOW SPOTS...SO
I WILL CHANGE COVERAGE TO AREAS FROM PATCHY.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...

HIGH PRESSURE WILL CONTINUE TO BE IN PLACE AT THE SURFACE WITH THE
CUTOFF UPPER LOW MAKING ITS WAY EAST JUST SOUTH OF THE AREA ON
MONDAY. THIS COULD LEAD TO INCREASED CLOUD COVER IN THE SOUTH BUT
THAT/S IT AS FORCING IS FAIRLY WEAK AND MOISTURE IS LIMITED. UPPER
RIDGING WILL BE IN PLACE FOR MONDAY NIGHT AND TUESDAY WHICH WILL
KEEP THE AREA DRY. BY TUESDAY NIGHT THOUGH AN UPPER WAVE WILL
APPROACH AND BRING SOME FORCING TO THE AREA THAT COULD LAST THROUGH
WEDNESDAY BUT SHOULD BE THROUGH BY WEDNESDAY NIGHT. THERE IS STILL
SOME MODEL DISCREPANCY ON TIMING...BUT THE NAM SEEMS TO BE A SLOW
OUTLIER WITH THE SREFS/GFS/ECMWF ALL POINTING TO SOMETIME IN THE
TUESDAY NIGHT TO WEDNESDAY TIME FRAME AND ONLY THE NAM HOLDING ON TO
PRECIP INTO WEDNESDAY NIGHT. ONLY WENT WITH A SLIGHT CHANCE FOR
PRECIPITATION ON TUESDAY NIGHT AND WEDNESDAY SINCE THERE IS HIGH
PRESSURE AT THE SURFACE AND MOISTURE WILL BE LIMITED...BUT UPPER
FORCING IS SUFFICIENT TO JUSTIFY A SLIGHT CHANCE. SOUNDINGS FOR THAT
TIME SUGGEST SNOW AS THE POTENTIAL PRECIPITATION TYPE SHOULD IT
OCCUR.

FOR TEMPERATURES GENERALLY USED A GUIDANCE CONSENSUS WITH GOOD
AGREEMENT THERE. THE EXCEPTION IS ON WEDNESDAY WHEN COLD ADVECTION
IS IN PLACE AN 850 MB TEMPERATURES FROM THE ECMWF AND GFS BOTH SHOW
-10C OVER THE AREA. THOUGHT GUIDANCE WAS TOO HIGH GIVEN THE ABOVE
AND INSTEAD WENT WITH AN AVERAGE OF THE GFS AND ECM.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...

THERE ARE A COUPLE OF PERIODS WHERE SLIGHT CHANCE OF PRECIP IS
POSSIBLE MAINLY WEDNESDAY EVENING AND AGAIN FRIDAY.  HOWEVER MODELS
HAVE TRENDED DRIER WITH EACH RUN AND ALL BLEND ONLY GIVES A 15-20
PERCENT CHANCE AT MOST OF PRECIP THOSE PERIODS.  AT THIS POINT HAVE
DECIDED TO TAKE OUT MENTION OF PRECIP AS NOW DRY THROUGH THE PERIODS
AND THERE ARE ONLY A FEW WEAK SYSTEMS TO KEY ON.

MODELS MOVE AN UPPER SHORT WAVE ACROSS THE OHIO VALLEY EARLY
WEDNESDAY EVENING. THEN HIGH PRESSURE WILL DOMINATE OUR WEATHER
THURSDAY.  ON FRIDAY A DRY COLD FRONT WILL MOVE ACROSS OUR REGION AS
A BROAD UPPER TROUGH ROTATES ACROSS THE GREAT LAKES AND MIDWEST.
ONCE AGAIN THERE IS LIMITED MOISTURE AVAILABLE WITH THIS SYSTEM.
HIGH PRESSURE BEHIND THIS SYSTEM WILL MOVE ACROSS OUR REGION OVER
THE WEEKEND.  OVERALL DID NOT MAKE ANY SIGNIFICANT CHANGES TO ALL
BLEND PARAMETERS.

&&

.AVIATION /DISCUSSION FOR THE 06/09Z TAF UPDATE/...

UPDATE...

FOG IS PROVING TO BE PROBLEMATIC AT KLAF AND KHUF WITH
VISIBILITIES IN THE LIFR/IFR CATEGORIES. ELSEWHERE...CONDITIONS
ARE HOLDING UP AT KIND AND KBMG...SO TEMPO MVFR THROUGH MON 13Z
STILL LOOKS REASONABLE.


PREVIOUS DISCUSSION...
MAINLY VFR THROUGH THE PERIOD...WITH A PERIOD OF MVFR POSSIBLE NEAR
DAYBREAK TOMORROW.

HIGH PRESSURE HAS BUILT IN...ERODING ANY LEFTOVER CLOUD...AND
ALLOWING SIGNIFICANT DRYING AT THE SURFACE THROUGH A LIGHT NORTHERLY
SURFACE FLOW AND AMPLE SUNSHINE WITH THE SUPERB WEATHER YESTERDAY
AFTERNOON. ALTHOUGH WINDS WILL BE CALM TO LIGHT AND SKIES WILL BE
CLEAR OVERNIGHT...DO NOT EXPECT SIGNIFICANT FOG TO FORM. WILL
INCLUDE SOME HIGH END MVFR FOG FOR A FEW HOURS NEAR DAYBREAK AT ALL
SITES IN TEMPO GROUPS. NAM/RUC SOUNDINGS SHOW DECENT SATURATION NEAR
THE SURFACE...GFS/SREF SOUNDINGS DO NOT. NAM SOUNDING IS MOST
FAVORABLE...BUT ITS 00Z MOS DOES NOT BRING ANY RESTRICTIONS IN.

WINDS WILL BE CALM TO LIGHT OVERNIGHT...BECOMING WEST/SOUTHWESTERLY
TOMORROW BUT REMAINING BELOW 10KT. MAY SEE INFREQUENT GUSTS INTO THE
LOW TEENS BUT SURFACE PRESSURE GRADIENT APPEARS FAIRLY WEAK...SO
WILL NOT INCLUDE ANY MENTION AT THIS TIME.


&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SYNOPSIS...JK
NEAR TERM...JK
SHORT TERM...CP
LONG TERM....JH
AVIATION...TDUD







AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 1138 PM EST SUN FEB 5 2012

.UPDATE...

THE AVIATION SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...

HIGH PRESSURE IS GOING TO COVER INDIANA THROUGH MONDAY. A SERIES
OF WEAK DISTURBANCES WILL PASS OVERHEAD LATER THIS WEEK.
HOWEVER...HIGH PRESSURE WILL BE THE RULE AT THE SURFACE SO
PRECIPITATION CHANCES SHOULD STAY SMALL.

&&

.NEAR TERM /TONIGHT/...

MAIN ISSUES ARE TEMPERATURES AND FOG AS MODELS AND OBS ALL SUPPORT
CLEAR TONIGHT.

AT 01Z WINDS IN OBSERVATIONS INDICATED A WEAK SURFACE RIDGE TO OUR
WEST. RUC SAYS THIS WILL WORK EASTWARD AND ALMOST COMPLETELY KILL
OUR WINDS LATE TONIGHT. WITH THAT AND OUR CURRENT TEMPERATURES
ROUGHLY 3 DEGREES BELOW THE HOURLY GRIDS...I AM GOING TO DROP
MINS TONIGHT ABOUT A CATEGORY.

CLEAR WITH LIGHT WIND FAVORS FOG TONIGHT. BUFKIT SHOWS MOISTURE
DECREASING RAPIDLY WITH HEIGHT...A NEGATIVE. WITH OFFSETTING
FACTORS I WILL KEEP FOG IN THE FORECAST BUT WONT MENTION DENSE.
GIVEN DAMP GROUND WE MIGHT GET FOG OUTSIDE THE COMMON LOW SPOTS...SO
I WILL CHANGE COVERAGE TO AREAS FROM PATCHY.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...

HIGH PRESSURE WILL CONTINUE TO BE IN PLACE AT THE SURFACE WITH THE
CUTOFF UPPER LOW MAKING ITS WAY EAST JUST SOUTH OF THE AREA ON
MONDAY. THIS COULD LEAD TO INCREASED CLOUD COVER IN THE SOUTH BUT
THAT/S IT AS FORCING IS FAIRLY WEAK AND MOISTURE IS LIMITED. UPPER
RIDGING WILL BE IN PLACE FOR MONDAY NIGHT AND TUESDAY WHICH WILL
KEEP THE AREA DRY. BY TUESDAY NIGHT THOUGH AN UPPER WAVE WILL
APPROACH AND BRING SOME FORCING TO THE AREA THAT COULD LAST THROUGH
WEDNESDAY BUT SHOULD BE THROUGH BY WEDNESDAY NIGHT. THERE IS STILL
SOME MODEL DISCREPANCY ON TIMING...BUT THE NAM SEEMS TO BE A SLOW
OUTLIER WITH THE SREFS/GFS/ECMWF ALL POINTING TO SOMETIME IN THE
TUESDAY NIGHT TO WEDNESDAY TIME FRAME AND ONLY THE NAM HOLDING ON TO
PRECIP INTO WEDNESDAY NIGHT. ONLY WENT WITH A SLIGHT CHANCE FOR
PRECIPITATION ON TUESDAY NIGHT AND WEDNESDAY SINCE THERE IS HIGH
PRESSURE AT THE SURFACE AND MOISTURE WILL BE LIMITED...BUT UPPER
FORCING IS SUFFICIENT TO JUSTIFY A SLIGHT CHANCE. SOUNDINGS FOR THAT
TIME SUGGEST SNOW AS THE POTENTIAL PRECIPITATION TYPE SHOULD IT
OCCUR.

FOR TEMPERATURES GENERALLY USED A GUIDANCE CONSENSUS WITH GOOD
AGREEMENT THERE. THE EXCEPTION IS ON WEDNESDAY WHEN COLD ADVECTION
IS IN PLACE AN 850 MB TEMPERATURES FROM THE ECMWF AND GFS BOTH SHOW
-10C OVER THE AREA. THOUGHT GUIDANCE WAS TOO HIGH GIVEN THE ABOVE
AND INSTEAD WENT WITH AN AVERAGE OF THE GFS AND ECM.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...

THERE ARE A COUPLE OF PERIODS WHERE SLIGHT CHANCE OF PRECIP IS
POSSIBLE MAINLY WEDNESDAY EVENING AND AGAIN FRIDAY.  HOWEVER MODELS
HAVE TRENDED DRIER WITH EACH RUN AND ALL BLEND ONLY GIVES A 15-20
PERCENT CHANCE AT MOST OF PRECIP THOSE PERIODS.  AT THIS POINT HAVE
DECIDED TO TAKE OUT MENTION OF PRECIP AS NOW DRY THROUGH THE PERIODS
AND THERE ARE ONLY A FEW WEAK SYSTEMS TO KEY ON.

MODELS MOVE AN UPPER SHORT WAVE ACROSS THE OHIO VALLEY EARLY
WEDNESDAY EVENING. THEN HIGH PRESSURE WILL DOMINATE OUR WEATHER
THURSDAY.  ON FRIDAY A DRY COLD FRONT WILL MOVE ACROSS OUR REGION AS
A BROAD UPPER TROUGH ROTATES ACROSS THE GREAT LAKES AND MIDWEST.
ONCE AGAIN THERE IS LIMITED MOISTURE AVAILABLE WITH THIS SYSTEM.
HIGH PRESSURE BEHIND THIS SYSTEM WILL MOVE ACROSS OUR REGION OVER
THE WEEKEND.  OVERALL DID NOT MAKE ANY SIGNIFICANT CHANGES TO ALL
BLEND PARAMETERS.

&&

.AVIATION /DISCUSSION FOR THE 06/06Z TAFS/...

MAINLY VFR THROUGH THE PERIOD...WITH A PERIOD OF MVFR POSSIBLE NEAR
DAYBREAK TOMORROW.

HIGH PRESSURE HAS BUILT IN...ERODING ANY LEFTOVER CLOUD...AND
ALLOWING SIGNIFICANT DRYING AT THE SURFACE THROUGH A LIGHT NORTHERLY
SURFACE FLOW AND AMPLE SUNSHINE WITH THE SUPERB WEATHER YESTERDAY
AFTERNOON. ALTHOUGH WINDS WILL BE CALM TO LIGHT AND SKIES WILL BE
CLEAR OVERNIGHT...DO NOT EXPECT SIGNIFICANT FOG TO FORM. WILL
INCLUDE SOME HIGH END MVFR FOG FOR A FEW HOURS NEAR DAYBREAK AT ALL
SITES IN TEMPO GROUPS. NAM/RUC SOUNDINGS SHOW DECENT SATURATION NEAR
THE SURFACE...GFS/SREF SOUNDINGS DO NOT. NAM SOUNDING IS MOST
FAVORABLE...BUT ITS 00Z MOS DOES NOT BRING ANY RESTRICTIONS IN.

WINDS WILL BE CALM TO LIGHT OVERNIGHT...BECOMING WEST/SOUTHWESTERLY
TOMORROW BUT REMAINING BELOW 10KT. MAY SEE INFREQUENT GUSTS INTO THE
LOW TEENS BUT SURFACE PRESSURE GRADIENT APPEARS FAIRLY WEAK...SO
WILL NOT INCLUDE ANY MENTION AT THIS TIME.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SYNOPSIS...JK
NEAR TERM...JK
SHORT TERM...CP
LONG TERM....JH
AVIATION...NIELD






AREA FORECAST DISCUSSION

NWS QUAD CITIES IA IL

 1136 PM CST SUN FEB 5 2012


.AVIATION...
LARGE AREA OF IFR/LIFR STRATUS AND LIGHT FOG REMAINS UNDER LOW
LEVEL INVERSION OF WEAK SURFACE HIGH PRESSURE OVER MOST OF IOWA.
TRENDS SUPPORTS CLOUD BASES OF 300 TO 900 FEET ALL TERMINALS REST
OF TONIGHT AND VISIBILITIES OF 3 TO 6 MILES DECREASING TO 1 TO 3
MILES AFTER MIDNIGHT. WESTERLY AND SOUTHWESTERLY WINDS TO BRING IN
MIXING AND DRIER AIR ACROSS ALL TERMINALS WITH CLEARING SKIES AND
7 MILES FOR VFR CONDITIONS BETWEEN 16-18Z. THEN...VFR CONDITIONS TO
CONTINUE AT LEAST THROUGH 07/06Z.   ..NICHOLS..

&&

.PREV DISCUSSION... /ISSUED 309 PM CST SUN FEB 5 2012/

SYNOPSIS...
STRATUS HAS BEEN THE MAIN FOCUS OF THE DAY...WITH STRATUS
EXTENDING FROM SOUTHEAST MINNESOTA AND WESTERN WISCONSIN...NEARLY
ALL OF IOWA...AND EXTENDING BACK INTO EASTERN NEBRASKA. IT HAS
MAINLY AFFECTED THE WESTERN HALF OF THE FORECAST AREA...WITH AREAS
ALONG AND EAST OF THE MISSISSIPPI RIVER MOSTLY IN THE CLEAR. THIS
STRATUS IS TRAPPED UNDER A STRONG SURFACE HIGH PRESSURE WHICH IS
CENTERED OVER KANSAS....WITH A BROAD RIDGE EXTENDING NORTHEAST UP
OVER IOWA AND EXTENDING UP INTO WISCONSIN. SOUNDINGS FROM THIS
MORNING... AIRCRAFT REPORTS AND AIRCRAFT SOUNDINGS FROM THE AREA
TODAY INDICATE THAT WE HAVE A SATURATED LAYER AROUND
950MB...GENERALLY ABOUT 1000 TO 1500 FEET THICK DEPENDING ON THE
LOCATION...WITH A STEEP INVERSION JUST ABOVE IT. AT UPPER LEVELS
THE UPPER LEVEL LOW THAT PRODUCED RAIN AND SNOW YESTERDAY OVER
IOWA IS NOW SHIFTING RAPIDLY SOUTH ACROSS MISSOURI. CLOUDS...BUT
LITTLE RAIN IS CONTINUING TO AFFECT SOUTHERN MISSOURI AND INTO
KENTUCKY AND TENNESSEE. ..LE..

SHORT TERM...TONIGHT AND MONDAY...
STRATUS REMAINS THE MAIN FORECAST CHALLENGE.  THE LARGE SCALE MODELS
WE ARE USED TO DEPENDING UPON HAVE NOT EVEN INITIALIZED THE LOW
LEVEL MOISTURE ASSOCIATED WITH THE STRATUS CORRECTLY.  THUS...THESE
MODELS ARE OF LITTLE USE IN PREDICTING IT.  OF THE MESOSCALE
MODELS...ONLY THE HRRR SEEMS TO HAVE ANY SORT OF HANDLE ON THE
STATUS OF THE STRATUS.  THUS...BETWEEN IT...EXPERIENCE AND
NOWCASTING TECHNIQUES ARE ABOUT THE ONLY DECENT FORECAST TOOLS
TODAY.  SINCE THE MOISTURE IS TRAPPED BENEATH THE SURFACE RIDGE
AXIS...ANTICIPATE THE STRATUS SHOULD REFORM AND SPREAD BACK
SOUTHEAST AGAIN THIS EVENING...ADVECTING ALONG IN THE NORTHWEST
925MB FLOW.  OVER THE DAKOTAS TODAY THINGS SEEM TO HAVE CLEARED
NICELY WHERE THESE WINDS TURNED WESTERLY AND THE DOWNSLOPE COMPONENT
COULD HELP ACT TO DRY AND WARM THIS LAYER...HELPING TO DISSIPATE THE
CLOUDS.  HOWEVER...DOWNSLOPE WILL NOT HELP US THIS FAR EAST AND THOUGH I
EXPECT THE 925MB WINDS TO TURN WESTERLY FOR US AFTER MIDNIGHT
TONIGHT THE STRATUS SHOULD LINGER THROUGH THE OVERNIGHT HOURS. UNDER
THE STRATUS LAST NIGHT MIN TEMPS ONLY DROPPED INTO THE MID TO UPPER
20S...SO HAVE CONTINUED THIS.

MONDAY MORNING AND AFTERNOON LOOKS LIKE OUR BEST OPPORTUNITY FOR
CLEARING OUT THIS BAND OF STRATUS.  THE WESTERLY 925MB FLOW
STRENGTHENS TO 925MB...SOME WARM AIR ADVECTION AT THAT LAYER SHOULD
HELP TO DISSIPATE IT...ALONG WITH SHEER BODILY ADVECTION.  IT IS
NOTORIOUSLY HARD TO GET RID OF STRATUS THIS TIME OF YEAR...BUT THAT
IS USUALLY DUE TO ESTABLISHED SNOWCOVER. HOPEFULLY WITH THE SNOW
GONE FOR OUR AREA WE CAN GET RID OF THE STRATUS SOONER.
ANTICIPATING MORE CLOUD COVER OVER THE EAST HAVE KEPT MAX TEMPS
THERE COOLER...BUT NOT AS COOL AS THE NORTHWEST IS TODAY.
OTHERWISE...40-45 IS NOT UNREASONABLE AS LONG AS WE CLEAR BY EARLY
AFTERNOON.   ..LE..

LONG TERM...MONDAY NIGHT THROUGH NEXT SUNDAY...
FORECAST FOCUS ON POTENTIAL FOR FLURRIES MONDAY NIGHT AND TUESDAY
OTHERWISE MAINLY A DRY PERIOD. BRIEF SHOT OF ARCTIC AIR AT THE END
OF THE NEW WORK WEEK.

MONDAY NIGHT AND TUESDAY...COLD FRONT TO ARRIVE MONDAY NIGHT WITH
POTENTIAL FOR SOME FLURRIES OR BRIEF LIGHT SNOW. EXTENSIVE LOW
STRATUS TO DEVELOP BEHIND THE FRONT AS WE COLD ADVECT MONDAY NIGHT
WITH LOW CLOUDS CONTINUING ON TUESDAY AS SURFACE WINDS TURN
NORTHEAST. WILL CONTINUE WITH SLIGHT CHANCE POPS IN OUR SOUTH BUT
EVEN THE ECM HAS BACKED OFF ON QPF AMOUNTS. TEMPERATURES ON TUESDAY
ONLY COOL DOWN TO NEAR NORMAL FOR EARLY FEBRUARY. MAXIMUM
TEMPERATURES EXPECTED TO BE IN THE 30S.

TUESDAY NIGHT THROUGH THURSDAY...EXTENSIVE LOW STRATUS TO REMAIN
TUESDAY NIGHT AND FOR MOST OF WEDNESDAY WITH FORECAST SOUNDINGS
INDICATING NORTHEAST LOW LEVEL WINDS. WILL TRY TO CLEAR THE SKIES
OUT BY WEDNESDAY NIGHT AS WINDS TURN WEST TO SOUTHWEST. MAX TEMPS
ABOUT NORMAL WITH HIGHS IN THE 30S TO NEAR 40.

THURSDAY NIGHT THROUGH SATURDAY NIGHT...TROUGH STRONGLY DIGS INTO
THE MIDWEST/GREAT LAKES TIED TO A DEEP LOW NEAR HUDSON BAY. THIS
SENDS AN ARCTIC FRONT SWEEPING RAPIDLY THROUGH THE DVN CWA THURSDAY
NIGHT. HOWEVER DUE TO THE LACK OF SIGNIFICANT SNOW COVER TO OUR
NORTH AND NO SNOW COVER IN THE DVN CWA THIS AIRMASS WILL BE MODIFIED
BY THE TIME IT GETS HERE. THE COLDEST DAY WILL BE FRIDAY BUT
SATURDAY WONT EXACTLY BE A PICNIC EITHER. HIGHS WILL BE IN THE MID
20S NORTH TO LOWER 30S SOUTH WITH LOWS MAINLY IN THE TEENS. WARM
ADVECTION ALREADY UNDERWAY BY SATURDAY NIGHT AS ARCTIC HIGH PRESSURE
SHIFTS INTO THE OHIO VALLEY RETURNING SOUTH WINDS TO THE REGION.

SUNDAY...NICE WARM-UP BEGINS AS UPPER LEVEL FLOW BECOMES ZONAL TO
SOUTHWEST WITH SOUTHWEST SURFACE WINDS. MAX TEMPS SHOULD PUSH WELL
INTO THE 30S NORTH TO LOWER 40S SOUTH. EVEN WARMER TEMPERATURES
EARLY NEXT WEEK.   ..HAASE..

&&

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

$$

NICHOLS






AREA FORECAST DISCUSSION

NWS GOODLAND KS

 746 PM MST TUE FEB 7 2012

.UPDATE...
741 PM MST TUE FEB 7 2012

JUST COMPLETED AN UPDATE. SATELLITE SHOWING CLOUD COVER IS SLOW TO
ERODE. AREA 00Z SOUNDINGS SHOW A STRONG INVERSION WITH WARMING
ALOFT EXPECTED DURING THE NIGHT. SO SLOWED THE CLEARING PROCESS
AND WARMED MINS ACCORDINGLY BASED ON REALITY AND LATEST MODEL
TRENDS. RUC LOOKS TO BE HANLDING THE BOUNDARY LAYER RH THE BEST AT
THIS TIME. ALSO BASED ON THE 00Z SOUNDINGS AND LATEST
RUC...HRRR...AND NAM SHOWING REDUCED VISIBILITIES IN THE SAME
PLACE...DECIDED TO ADD PATCHY FREEZING FOG INTO THE NORTHWEST HALF
TO TWO-THIRDS.

BULLER
&&

.DISCUSSION...
245 PM MST TUE FEB 7 2012

TONIGHT...PRIMARY FORECAST CONCERN WILL BE HOW COLD OVERNIGHT LOW
TEMPERATURES WILL DROP AND HOW QUICKLY CLOUDS WILL CLEAR THIS
EVENING...AND THE DEVELOPMENT OF FOG. IF CLOUDS LINGER OR FOG
DEVELOPS ACROSS THE AREA...CURRENT OVERNIGHT LOW TEMPERATURES MAY BE
TOO COLD. IF SKIES CLEAR COMPLETELY ALLOWING FOR MAXIMUM RADIATIONAL
COOLING...TEMPERATURES MAY BE TOO WARM.

CURRENT WV SATELLITE IMAGERY SHOWS UPPER LEVEL TROUGH MOVING ACROSS
THE CENTRAL CONUS WITH A SURGE OF COLD AIR MOVING DOWN OUT OF CANADA
INTO THE NORTHERN PLAINS. A FEW FLURRIES MAY STILL BE POSSIBLE LATE
THIS AFTERNOON BUT WILL END BY THIS EVENING. SUBSIDENCE WILL QUICKLY
MOVE INTO WESTERN AND CENTRAL KANSAS OVERNIGHT BEHIND THE DEPARTING
SYSTEM...DROPPING TEMPERATURES INTO THE SINGLE DIGITS ACROSS ALL BUT
THE SOUTHERN PERIPHERY OF THE CWA. GIVEN LIGHT WINDS AND SUFFICIENT
LOW LEVEL MOISTURE...THERE IS A CHANCE OF PATCHY FOG DEVELOPING
ACROSS AT LEAST THE NORTHERN HALF OF THE CWA. HOWEVER...CONFIDENCE
NOT HIGH ENOUGH WITH CURRENT CLOUD COVER SLOW TO EXIT AND MAY LIMIT
RADIATIONAL COOLING.

PMM

WEDNESDAY-FRIDAY...DRY WITH WARMING TEMPERATURES WEDNESDAY AND
THURSDAY. A BACKDOOR FRONT MOVES IN FROM THE NORTH/NORTHEAST
FRIDAY LEADING TO COLDER TEMPERATURES...ESPECIALLY ACROSS THE
EAST/NORTHEAST. OVERNIGHT LOWS WILL CONTINUE TO BE COLD IN SNOW
PACK AREAS WHERE SINGLE DIGITS EXPECTED...FURTHER SOUTH OUT OF THE
SNOW PACK TEENS TO LOW 20S EXPECTED.

FRIDAY NIGHT-SATURDAY...UPPER LEVEL DISTURBANCE AIDED BY
FAVORABLE POSITION TO JET STREAK MOVES INTO THE AREA WITH BEST
MOISTURE AND LIFT FAVORING THE NORTHEAST 1/2-1/3 OF THE AREA FOR
SOME LIGHT SNOW. HIGH TEMPERATURES GENERALLY IN THE 30S...WARMEST
ACROSS THE SOUTHWEST PART OF THE AREA.

SATURDAY NIGHT-SUNDAY NIGHT...UPPER TROUGH MOVES ACROSS THE AREA
DURING THE PERIOD PRODUCING SOME SNOW. DIFFERENCES IN THE SPEED
AND INTENSITY OF THE TROUGH PREVENT GETTING TOO DETAILED AT
PRESENT TIME BUT CANT RULE OUT SOME ACCUMULATING SNOW. BEST TIME
WOULD BE SUNDAY-SUNDAY NIGHT. HIGH TEMPERATURES SUNDAY IN THE 30S.

MONDAY...SHOULD SEE A DRY DAY WITH HIGHS IN THE UPPER 30S TO MID
40S (EAST TO WEST). HOWEVER...POSSIBLE SNOW COVER FROM SATURDAY
NIGHT-SUNDAY NIGHT SYSTEM COULD MAKE CURRENT FORECAST HIGHS
OPTIMISTIC.

MONDAY NIGHT-TUESDAY...ANOTHER IN A SERIES OF UPPER LOWS/TROUGHS
MOVES ACROSS THE AREA. LIGHT RAIN AND/OR LIGHT SNOW EXPECTED.

007
&&

.AVIATION...
445 PM MST TUE FEB 7 2012

FOR THE 00Z TAFS...LOW LEVEL MOISTURE WILL CONTINUE TO BE IN PLACE
ACROSS THE REGION TONIGHT THROUGH WEDNESDAY MORNING. MVFR/IFR CIGS
WILL ALSO BE IN PLACE THROUGH AROUND 15-16Z AT WHICH TIME LOW LEVEL
CIGS WILL SCATTER OUT AND BE REPLACED WITH MID/HIGH CLOUDS. WINDS
WILL BE ORIGINALLY FROM THE NORTHWEST AND WITH A SURFACE RIDGE
MOVING EASTWARD...WINDS WILL SWITCH TO THE SOUTH ON THE BACKSIDE
OF THE RIDGE.

BAS
&&

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

$$








THE PREVIOUS SHORT TERM FORECAST DISCUSSION FOLLOWS...



 /TONIGHT THROUGH WEDNESDAY NIGHT/

A COMPLICATED FORECAST TONIGHT THROUGH WEDNESDAY NIGHT. THE MODELS
ARE IN GOOD AGREEMENT THAT A FAIRLY PROGRESSIVE CLIPPER SYSTEM WILL
MAKE ITS WAY ACROSS THE OHIO AND TENNESSEE VALLEY REGIONS FROM AROUND
DAWN TOMORROW THROUGH LATE TOMORROW NIGHT. THE NAM12 AND GFS MODELS
WERE RELIED UPON HEAVILY TO CONSTRUCT THE FORECAST FOR THE PERIOD
TONIGHT THROUGH TOMORROW NIGHT. THE MODEL PLAN VIEWS ARE ALL
SUGGESTING THE POSSIBILITY OF AN ALL SNOW EVENT...HOWEVER...THE
CORRESPONDING TIME HEIGHT CROSS SECTIONS AND SOUNDINGS ARE PAINTING A
MORE MUDDLED PICTURE. THE TIME HEIGHTS AND SOUNDINGS ARE SHOWING A
LAYER OF SURFACE AIR 2-4 DEGREES ABOVE FREEZING OVERNIGHT INTO EARLY
TOMORROW...WHICH WOULD MAKE IT DIFFICULT FOR THE PASSING CLIPPER TO
PRODUCE ALL SNOW. BASED ON THESE DATA A RAIN/SNOW MIX SEEMS MOST
LIKELY FOR MOST OF THE FORECAST AREA AFTER DAWN TOMORROW THROUGH
ABOUT MID MORNING...AS IT APPEARS A GOOD DEAL OF THE SNOW WILL MELT
BEFORE IT CAN REACH THE SURFACE. THE EXCEPTIONS WOULD BE AREAS ALONG
AND NORTH OF THE I64 CORRIDOR...WHERE SUBFREEZING AIR WILL LIKELY BE
PRESENT...AND THE HIGHER ELEVATIONS ABOVE 2000 FEET ALONG THE
VIRGINIA AND WEST VIRGINIA BORDERS. THE NORTHWEST COUNTIES COULD SEE
LIGHT ACCUMULATIONS OF SNOW EARLY TOMORROW ON GRASSY AREAS AND
ELEVATED SURFACES...WITH LESS THAN AN INCH OF ACCUMULATION EXPECTED.

WITH ROAD SURFACES AS WARM AS THEY ARE ACROSS EASTERN KENTUCKY...IT
DOES NOT APPEAR LIKELY THAT ANY SNOW WILL BE ABLE TO ACCUMULATE ON
THE ROADS. HOWEVER...IF TEMPERATURES DROP EVEN A COUPLE OF DEGREES
COOLER AREA WIDE THAN 4 PM FORECAST IS GOING BE DEPICTING...MORE
WIDESPREAD LIGHT SNOW ACCUMULATIONS COULD OCCUR. FOR NOW...DUE TO THE
AMOUNT UNCERTAINTY INVOLVED...DECIDED TO GO WITH ONLY A RAIN SNOW MIX
FOR NOW. ALSO INCREASED THE LIKELIHOOD OF PRECIPITATION TOMORROW...AS
THE MODELS ARE PRODUCING ENOUGH QPF TO WARRANT HAVING HIGHER
PRECIPITATION PROBABILITIES THAN THE LATEST GUIDANCE IS SUGGESTING.
WILL ISSUE A SPECIAL WEATHER STATEMENT LATER IN THE SHIFT TO ADDRESS
THE TYPE OF PRECIP EXPECTED LATER TONIGHT AND EARLY TOMORROW.

THE ONE MAJOR CHANGE MADE TO THE FORECAST WAS TO SLOW DOWN THE
EASTWARD PROGRESSION OF THE AFOREMENTIONED CLIPPER SYSTEM...AS
TEMPERATURES ALOFT ARE NOT NEARLY AS COLD AS THEY USUALLY ARE THIS
TIME OF YEAR AND WINDS ALOFT ARE NOT NEARLY AS STRONG AS THEY USUALLY
ARE. THEREFORE...THE CLIPPER SYSTEM LIKELY WONT HAVE QUITE AS MUCH
FORWARD SPEED AS THE INHERITED FORECAST WAS SUGGESTING. THAT BEING
SAID...THE TIMING OF PRECIPITATION ONSET AND PROGRESSION ACROSS THE
FORECAST WERE UPDATED TO REFLECT THE SLOWER TIMING OF THE
CLIPPER...BY ROUGHLY 5 OR 6 HOURS. THE CORRESPONDING SKY
COVER...WEATHER...AND QPF GRIDS WERE ALSO UPDATED TO REFLECT THE
SLOWER TIMING. THE QPF FORECAST WAS BASED ON A COMBINATION OF THE
LATEST HPC GUIDANCE AND WWD SNOWFALL FORECAST. THE WWD FORECAST
GRAPHIC WAS IN GOOD AGREEMENT WITH WHERE THE NEW FORECAST IS
SUGGESTING SNOW WILL FALL...SO THAT SEEMED LIKE A SOUND BASIS FOR THE
SNOW FORECAST FOR TOMORROW.

AS FOR TEMPERATURES...WENT PRETTY CLOSE TO THE COOLER METMOS LOWS FOR
TONIGHTS MINIMUM TEMPS...AND SLIGHTLY COOLER THAN MOS FOR TOMORROWS
HIGHS...AS CLOUD COVER SHOULD EFFECTIVELY KEEP TEMPERATURES FROM
RISING TO THE NUMBERS SUGGESTED BY THE MAV/METMOS DATA. DEWPOINTS AND
WINDS WERE ADJUSTED A BIT TOO...BUT ONLY SMALL CHANGES WERE NEEDED.

.LONG TERM.../THURSDAY THROUGH TUESDAY/

HIGH PRESSURE OVER THE REGION WELL DEPICTED IN ALL MODELS. A COLD
TROF DROPS OUT OF CANADA BY FRIDAY MORNING AS THE HIGH PRESSURE
EASES OFF THE CAROLINA COAST. THIS TROF ACCOMPANIED BY A SFC COLD
FRONT THAT LOOKS TO RADICALLY CHANGE THE TEMPERATURE PATTERN ACROSS
THE OH/TN RIVER VALLEYS THIS WEEKEND. BOTH THE 12Z GFS AND ECMWF
INDICATE A RETURN FLOW OF MOISTURE UP THRU THE SRN PLAINS EVEN AS
THE FRONT PICKS UP MOISTURE AS IT TRACKS ACROSS THE GREAT LAKES. BY
FRI EVENING THE COLD FRONT TAPS INTO THE ADDITIONAL MOISTURE TO DROP
SOME PCPN OVER ERN KY. THE ECMWF IS MORE AGGRESSIVE WITH THE PCPN.
HAVE CHOSEN TO BLEND THE 2 MODELS WHICH BRINGS PCPN FOR THE ENTIRE
CWFA LATE FRI INTO SAT. TEMPS WILL INITIALLY START OUT WARM ENUF FOR
ALL RAIN BUT WILL SEE A MIX AND THEN ALL SNOW BY EARLY SAT MORNING.
SNOW WILL LINGER INTO THE DAY ON SAT FOR OUR MTN COUNTIES IN THE
EAST WHICH COULD BRING TOTAL SNOW FALL FOR THIS EVENT TO AROUND 1/2
INCH IN THE MTNS...ESP ABOVE 2K FEET...WHILE THE POSSIBILITY OF
ACCUMULATING SNOW EXISTS FOR THE REMAINDER OF THE FCST AREA BUT
GENERALLY A TENTH OF AN INCH OR LESS. HIGH TEMPS ON FRI BEFORE THE
FRONT WILL CLIMB INTO THE MID 40S BUT WILL PLUNGE INTO THE MID 30S
FOR BOTH SAT/SUN WITH SAT NITE LOWS IN THE MID TEENS. HIGH PRESSURE
WILL BRING A WARMING TREND TO THE EARLY WORK WEEK WITH MID 40S FOR
MON AND NEAR 50 BY TUE. EXPECT AN INCREASE IN CLOUDS BY TUE AFTN AS
THE NEXT COLD FRONT...MAINLY A GLANCING BLOW...SWEEPS ACROSS THE
GREAT LAKES AS A SFC REFLECTION OF THE NEXT SHORT WAVE TO ROTATE
AROUND THE SEMI PERMANENT HUDSON BAY VORTEX.

&&

.AVIATION.../00Z TO 24Z/

VFR CONDITIONS WILL LAST THROUGH MOST OF THE NIGHT. THIS WILL BE
FOLLOWED BY A RAPID DETERIORATION BETWEEN ABOUT 10Z AND 14Z...
WITH LIGHT PRECIPITATION AND MVFR DEVELOPING. MVFR AND LOCALIZED IFR
WILL THEN LAST THROUGH THE DAY. A PERIOD OF STEADY PRECIPITATION IS
MOST LIKELY TO OCCUR N AND E OF A LINE FROM KSME TO KLOZ TO
K1A6...WITH THE STEADY PRECIPITATION TAPERING TO SCATTERED SHOWERS
FROM WEST TO EAST BETWEEN 15Z AND 21Z. ANY PRECIPITATION SW OF THE
KSME-KLOZ-K1A6 LINE IS MORE LIKELY TO REMAIN SPORADIC. WHERE
PRECIPITATION STARTS EARLY IN THE MORNING...IT IS LIKELY TO BEGIN AS
SNOW. HOWEVER...AS TEMPERATURES WARM...A MIX OF RAIN AND SNOW IS
EXPECTED LATER IN THE DAY.

&&

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

&&

$$

SHORT TERM...AR/HAL
LONG TERM....DUSTY
AVIATION...HAL






AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

 933 AM EST MON FEB 6 2012

.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY WEATHER THROUGH TUESDAY. A SOUTHBOUND
CANADIAN COLD FRONT WILL BRING SCATTERED SNOW SHOWERS LATE TUESDAY NIGHT
AND WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
PLENTY OF SUNSHINE IS FORECAST TODAY WITH HIGH PRESSURE MOVING
THROUGH THE OHIO VALLEY.

A FEW CUMULUS CLOUDS COULD FORM MAINLY ACROSS NORTHERN ZONES AND
ALONG THE RIDGES THIS AFTERNOON. OTHERWISE SKIES SHOULD BE CLEAR.
HIGH TEMPERATURES WILL BE 5 TO 8 DEGREES WARMER THAN NORMAL BASED
ON BLEND OF RECENT GFS MOS, LAMP, AND HRRR MODEL OUTPUT.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
UPPER LEVEL SYSTEM WILL MOVE THROUGH THE OHIO VALLEY TONIGHT WITH
COLD FRONT PUSHING THROUGH ON TUESDAY. MODELS ARE SHOWING VERY
LITTLE MOISTURE WITH THE FRONT, SO WILL LEAVE FORECAST DRY.

COLD ADVECTION BEHIND FRONT WILL BRING COLDER TEMPS TUESDAY NIGHT.
FRONT WILL STALL OVER THE MID-ATLANTIC LATE TUESDAY NIGHT AND AN
UPPER LEVEL DISTURBANCE WILL MOVE THROUGH THE OHIO VALLEY
WEDNESDAY. MOISTURE WILL ACCOMPANY THE NEXT WAVE AND WILL BRING
THE CHANCE FOR SNOW SHOWERS TO AT LEAST THE SOUTHERN HALF OF THE
REGION. ANOTHER PERIOD OF CAA WILL OCCUR BEHIND THE WAVE ON
WEDNESDAY.

ABOVE NORMAL TEMPS TUESDAY WILL BE FOLLOWED BY BELOW NORMAL TEMPS
ON WEDNESDAY.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
BLEND OF RECENT ECMWF AND GFS MODEL OUTPUT SHOWS A DEEP UPPER LOW
PASSING EASTWARD THROUGH EASTERN CANADA LATE IN THE WEEK. A COLD
FRONT WILL PASS THROUGH THE UPPER OHIO VALLEY BY LATE FRIDAY
BRINGING SCATTERED RAIN/SNOW SHOWERS AND A RETURN TO MORE
SEASONABLE TEMPERATURES. SURFACE HIGH PRESSURE AND DRIER AIR WILL
MOVE OVER THE APPALACHIANS BY SUNDAY.

&&

.AVIATION /14Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE WILL MAINTAIN VFR CONDITIONS THROUGH TONIGHT, WITH
SCATTERED CUMULUS CLOUDS THIS AFTERNOON. SOUTHWEST WINDS CAN REACH
10-15 KTS THIS AFTERNOON.

OUTLOOK...TONIGHT THROUGH FRIDAY...
VFR TUESDAY. SCATTERED COLD FRONTAL SNOW SHOWERS WITH RESTRICTIONS
POSSIBLE LATE TUESDAY NIGHT AND WEDNESDAY. VFR THURSDAY AND FRIDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$







AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

 646 AM EST MON FEB 6 2012

.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY WEATHER THROUGH TUESDAY. A SOUTHBOUND
CANADIAN COLD FRONT WILL BRING SCATTERED SNOW SHOWERS LATE TUESDAY NIGHT
AND WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
QUIET WEATHER TODAY WITH HIGH PRESSURE MOVING THROUGH THE OHIO
VALLEY. PER RECENT SATELLITE DATA, ADDED MENTION OF FOG PATCHES
ACROSS THE HIGHER PA-WV-MD MOUNTAINS TIL 9 AM.

PLENTY OF SUNSHINE WITH SOME CUMULUS CLOUDS POSSIBLE THIS
AFTERNOON. HIGH TEMPERATURES WILL BE 5 TO 8 DEGREES WARMER THAN
NORMAL BASED ON BLEND OF RECENT GFS MOS, LAMP, AND HRRR MODEL OUTPUT.


&&

.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
UPPER LEVEL SYSTEM WILL MOVE THROUGH THE OHIO VALLEY TONIGHT WITH
COLD FRONT PUSHING THROUGH ON TUESDAY. MODELS ARE SHOWING VERY
LITTLE MOISTURE WITH THE FRONT, SO WILL LEAVE FORECAST DRY.

COLD ADVECTION BEHIND FRONT WILL BRING COLDER TEMPS TUESDAY NIGHT.
FRONT WILL STALL OVER THE MID-ATLANTIC LATE TUESDAY NIGHT AND AN
UPPER LEVEL DISTURBANCE WILL MOVE THROUGH THE OHIO VALLEY
WEDNESDAY. MOISTURE WILL ACCOMPANY THE NEXT WAVE AND WILL BRING
THE CHANCE FOR SNOW SHOWERS TO AT LEAST THE SOUTHERN HALF OF THE
REGION. ANOTHER PERIOD OF CAA BEHIND THE WAVE ON WEDNESDAY.

ABOVE NORMAL TEMPS TUESDAY, WILL BE FOLLOWED BY BELOW NORMAL TEMPS
ON WED.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
BLEND OF RECENT ECMWF AND GFS MODEL OUTPUT SHOWS A DEEP UPPER LOW
PASSING EASTWARD THROUGH EASTERN CANADA LATE IN THE WEEK. A COLD
FRONT WILL PASS THROUGH THE UPPER OHIO VALLEY BY LATE
FRIDAY, BRINGING SCATTERED RAIN/SNOW SHOWERS AND A RETURN TO MORE
SEASONABLE TEMPERATURES. SURFACE HIGH PRESSURE AND DRIER AIR WILL
MOVE OVER THE APPALACHIANS BY SUNDAY.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE WILL MAINTAIN VFR CONDITIONS THROUGH TONIGHT, WITH
SCATTERED CUMULUS CLOUDS THIS AFTERNOON. SOUTHWEST WINDS CAN REACH
10-15 KTS THIS AFTERNOON.

OUTLOOK...TONIGHT THROUGH FRIDAY...
VFR TUESDAY. SCATTERED COLD FRONTAL SNOW SHOWERS WITH RESTRICTIONS
POSSIBLE LATE TUESDAY NIGHT AND WEDNESDAY. VFR THURSDAY AND FRIDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$







AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

 1245 PM EST MON FEB 6 2012

LATEST UPDATE...AVIATION...

.SYNOPSIS...(404 AM EST MON FEB 6 2012)
A COLD FRONT WILL CROSS THE REGION TONIGHT.  THIS SYSTEM WILL BRING
VERY LITTLE SNOW...HOWEVER IT WILL RETURN TEMPERATURES TO NEAR
NORMAL VALUES FOR MID WEEK.  ANOTHER SURGE OF COLDER AIR ARRIVES BY
FRIDAY AND INTO THE WEEKEND.  SOME LAKE EFFECT SNOW SHOWERS WILL BE
SEEN ALONG WITH THIS COLDER AIR.

&&

.SHORT TERM...(404 AM EST MON FEB 6 2012)
(TODAY THROUGH WEDNESDAY)
THE SKY FORECAST REMAINS THE BIGGEST CHALLENGE TODAY AND THE
RESULTANT AFFECTS ON THE REGION/S TEMPS.  A LARGE AREA OF STRATUS
COVERED MUCH OF WISCONSIN THIS MORNING AND IT WAS PRESSING EASTWARD
AT A 5-10 MPH PACE.  THAT SPEED ALONG WOULD SUGGEST THAT THE CLOUD
DECK WOULD NOT REACH THE MICHIGAN SHORE UNTIL MID AFTERNOON.
HOWEVER THERE WAS ALSO RANDOM PATCHES OF STRATUS ACROSS LOWER
MICHIGAN TOO.  THE RUC LOW LEVEL MOISTURE PROGS SUGGEST A RAPID
EXPANSION OF THE STRATUS SO THAT THE ENTIRE GRR CWA IS COVERED BY
CLOUDS BY 12Z.  THIS LOOKS UNREASONABLE TO ME.  HOWEVER BELIEVE THE
STRATUS WILL LIKELY SPEED UP IT/S EASTWARD TRACK AS IT MOVES ACROSS
THE LAKE THIS MORNING.  ALSO...THE RANDOM PATCHES MAY ALSO EXPAND
SOMEWHAT THIS MORNING.  BUT THEN THE ISSUE BECOMES...WHAT WILL THE
INCREASED MIXING DO TO THE STRATUS.  I SENSE THAT IT WILL HELP IT TO
ERODE SUCH THAT MUCH OF THE STRATUS BECOMES LESS OF A FACTOR BY MID
DAY.  SO I WILL PLAY THE FORECAST SUCH THAT SOME STRATUS WILL LINGER
THROUGH THE MORNING...BUT WILL BANK ON A MOSTLY SUNNY AFTERNOON AS
THE EASTWARD EDGE OF THE STRATUS MIXES OUT.  IF THIS INDEED OCCURS
TEMPS WILL REACH WELL INTO THE 40S AGAIN TODAY...IF IT DOES NOT
OCCUR TEMPS MAY HOLD FROM 35 TO 40.

THE ARCTIC FRONT IS STILL ON SCHEDULE FOR TONIGHT.  THE LACK OF DEEP
MOISTURE WILL RESULT IN NO SNOW OR PERHAPS A RANDOM FLURRY.  THE LOW
LEVEL FLOW BEHIND THE FRONT SHOULD BE 030-040...KEEPING ANY LAKE
EFFECT ON THE OTHER SIDE OF THE LAKE.  WE WILL HAVE TO KEEP AN EYE
ON POSSIBLE SNOW SHOWERS OFF OF SAGINAW BAY WHICH MAY MOVE INTO
AREAS AROUND ST. JOHNS BY TUESDAY.

HAVE LOW POPS IN FOR TUE AFTERNOON INTO TUESDAY NIGHT FOR AREAS
SOUTH OF I-96.   A SHORT WAVE COMES ACROSS THE LOWER GREAT LAKES AND
COMBINED WITH THE EXITING ARCTIC FRONT MAY PRODUCE SOME LIGHT SNOW.
LOW LEVEL WINDS SHOULD ALSO BACK TO THE NW BY LATE TUESDAY NIGHT
WHICH COULD BRING A FEW SNOW SHOWERS OFF THE LAKE.  BY WEDNESDAY THE
MOISTURE PROFILE BECOMES VERY SHALLOW AS RIDGING BUILDS INTO THE
AREA. EXPECT SUNSHINE WITH NEAR NORMAL TEMPS.

&&

.LONG TERM...(404 AM EST MON FEB 6 2012)
(WEDNESDAY NIGHT THROUGH SUNDAY)
A CLIPPER MOVES ACROSS NORTHERN LOWER MICHIGAN THURSDAY NIGHT
SWINGING AN ARCTIC FRONT SOUTH ACROSS THE FORECAST AREA.

LOOKS LIKE SOME SNOW WILL ACCOMPANY THE FROPA WITH STRONG SFC
CONVERGENCE. LAKE EFFECT BEHIND THE FRONT WILL CONTINUE INTO
SATURDAY BUT FLOW GOES NORTH AND THEN EVENTUALLY NORTHEAST WHICH
WOULD PUSH THE SNOW SHOWERS OFFSHORE. THIS COMBINED WITH INVERSION
HEIGHTS BELOW 10 KFT SHOULD LIMIT ACCUMS...WITH MOST OF THE SNOW
CONCENTRATED FAIRLY CLOSE TO THE LAKE MICHIGAN SHORE.

&&

.AVIATION...(1245 PM EST MON FEB 6 2012)
MAIN FOCUS WITH THIS FCST PACKAGE IS THE LOW CLOUD TRENDS. LOW
CLOUDS WITH MVFR AND IFR CONDITIONS HAVE OVERSPREAD JUST ABOUT ALL
OF THE AREA WEST OF INTERSTATE 69 THIS MORNING. KJXN AND KLAN HAVE
REMAINED EAST OF THE CLOUD COVER...AND DIURNAL MIXING SHOULD PREVENT
THE LOW CLOUDS FROM MOVING INTO THOSE AREAS. THE AIRPORTS THAT
CURRENTLY HAVE THE LOW CLOUDS IN PLACE SHOULD SEE A SLOW LIFTING OF
THE CIGS...AND THE CLOUDS SHOULD BREAK UP FROM EAST TO WEST AS
DIURNAL MIXING DISSIPATES THE CLOUD COVER. WHERE CLOUDS BREAK UP
WILL SEE THE BETTER POTENTIAL OF SOME WIND GUSTS UP AROUND 20 KNOTS
THROUGH SUNSET.

A COLD FRONT WILL APPROACH THE AREA THIS EVENING FROM THE NORTH.
MAINLY MVFR LOW CLOUDS AHEAD OF THE FRONT WILL MOVE IN AFTER
00Z...AND THE FRONT SHOULD THEN MOVE THROUGH A FEW HOURS LATER.
CLOUDS SHOULD BE THE MAIN IMPACT FROM THE FRONT ALONG WITH A WIND
SHIFT FROM W/SW TO NE. SOME FREEZING DRIZZLE WILL ALSO BE
POSSIBLE...BUT WE ARE NOT CONFIDENT ENOUGH AT THIS TIME TO MENTION
IN THE FCST. THE CLOUDS AND NE WINDS WILL HOLD IN THROUGH 18Z TUE.

&&

.MARINE...(404 AM EST MON FEB 6 2012)
SCA IN AFFECT FOR TODAY WITH WSW WINDS TO AROUND 20 KTS.  LOOKS LIKE
WE WILL SEE A BRIEF BREAK IN THE HIGHER WINDS AND WAVES EARLY
TONIGHT AS A COLD FRONT COMES THROUGH.  BUT THEN BEHIND THE FRONT
WAVES SHOULD INCREASE AGAIN LATE TONIGHT OR EARLY TUESDAY IN THE
COLD ADVECTION PATTERN.

&&

.HYDROLOGY...(404 AM EST MON FEB 6 2012)
MINIMAL HYDRO CONCERNS GIVEN THE LACK OF PCPN.  ALSO THE SNOW PACK
TO THE NORTH WILL END IT/S MELTING BY TONIGHT AS THE COLD FRONT
COOLS REGIONAL TEMPS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY ST. JOE TO MANISTEE THROUGH TODAY.

&&

$$

SYNOPSIS:     JK
SHORT TERM:   JK
LONG TERM:    OSTUNO
AVIATION:     NJJ
MARINE:       JK
HYDROLOGY:    JK






AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 1224 PM EST MON FEB 6 2012

UPDATED AVIATION DISCUSSION FOR 18Z TAFS

.SYNOPSIS...

IN CONTRAST TO LAST COUPLE NIGHTS...CLEAR SKIES ARE DOMINANT ACROSS
UPR MI THIS MORNING. STRATUS IS NOT TOO FAR AWAY THOUGH OVR MN AND
WI. SO FAR...THERE IS ENOUGH WIND OVR UPR MI TO PROHIBIT THE STRATUS
FM SURGING INTO UPR MI. COLD FRONT THAT WILL BRING A CHANGE TO THE
RECENT UNSEAONABLE WARMTH IS DROPPING ACROSS MANITOBA AND ONTARIO
THIS MORNING. STRATOCU IS INITIAL SIGN OF THE COLDER AIR WITH SFC
OBS TURNING UP SOME LGT SNOW BEHIND THE FRONT OVR NORTHERN ONTARIO.
COLDER AIR ARRIVING LATE TODAY AND TONIGHT WILL LEAD TO LK EFFECT
SNOW SHOWERS OVR NORTHERN UPR MI. AS HAS BEEN CASE MUCH OF THIS
WINTER...THIS COOL DOWN WILL BE BRIEF WITH TEMPERATURES MOVING BACK
TOWARD NORMAL AS SOON AS WEDNESDAY. APPEARS THAT MORE SUBSTANTIAL
COOL DOWN WILL RETURN BY LATE WEEK INTO THE WEEKEND AS PORTION OF
POLAR VORTEX OVER EASTERN CANADA SLIDES INTO GREAT LAKES/NORTHEAST
CONUS.
&&

.SHORT TERM /TODAY THROUGH TUESDAY/...

IN THE NEAR TERM...QUIET CONDITIONS AS SKIES SHOULD STAY MOSTLY
CLEAR. RUC13 PERFORMED WELL WITH STRATUS YDY...AND IT DOES INDICATE
STRATUS MAY TRY TO MAKE MOVE INTO SW FRINGES OF UPR MI FM WISCONSIN.
SINCE RUC13 IS OVERDOING NORTHERN EXTENT TO CLOUDS AT THIS HOUR...WILL
KEEP WITH MAINLY CLEAR SKIES. DESPITE THE CLEAR SKIES...TEMPS ARE
STILL IN THE UPR 20S TO LOWER AND EVEN MID 30S WITH STEADY WEST WINDS
BLOWING AHEAD OF COLD FRONT DROPPING ACROSS ONTARIO. ISOLATED INLAND
LOCATIONS WHERE WINDS GO CALM COULD STILL FALL TO LOW-MID 20S THROUGH
SUNRISE /ALREADY HAVE SOME 25F READINGS AT WAKEFIELD AND DOE
LAKE/...BUT FOR LARGE PART TEMPS WILL REMAIN STEADY ELSEWHERE.

TODAY...
COLD FRONT FCST TO MOVE INTO FAR NORTH CWA TOWARD MIDDAY. FRONT
SHOULD REACH SOUTHERN CWA AROUND KMNM BY 21Z THIS AFTN. STRATOCU MAIN
ISSUE INITIALLY AS THERE IS NOT A LOT OF COLD AIR AROUND JUST IN WAKE
OF FRONT...WITH H85 TEMPS WARMER THAN -8C. KEPT ISOLATED SNOW SHOWERS
RESTRICTED TO NW CWA THIS AFTN AS COOLER AIR GRADUALLY FILTERS INTO
UPR MI. OTHERWISE...BASED ON UPSTREAM TRENDS IN ONTARIO THIS
MORNING...MOST AREAS COULD SEE SOME FLURRIES JUST IN WAKE OF FROPA.
TEMPS SHOULD FALL OFF WITH PASSAGE OF FROPA...BUT DOES APPEAR THAT
SHARPER COOLING IS LAGGING INITIAL SURGE OF STRATOCU BY A FEW HOURS.
HEADED TOWARD REGIONAL CANADIAN FOR TEMPERATURE TRENDS TODAY. BASED
ON WARM START THIS MORNING AND WEST WINDS ALREADY STIRRING...SEEMS
LIKELY THAT DOWNSLOPE AREAS OF CNTRL /MARQUETTE TO ESCANABA TO
MENOMINEE/ HAVE SHOT TO REACH INTO 40S BY EARLY AFTN JUST AHEAD OF
FRONT. BY LATE AFTN...EXPECT MOST AREAS TO BE AT OR BLO
FREEZING...WITH 20S LIKELY IN THE HIGHER TERRAIN OF NW AND NCNTRL UPR
MI.

TONIGHT INTO TUESDAY...
REALLY GOOD AGREEMENT ON SPECIFICS FM 00Z GUIDANCE WITH EXTENT AND
DEPTH OF COLD AIR /H85 TEMPS AROUND -15C/ AND MOISTURE /AT LEAST UP
TO 5KFT WHICH INTERSECTS IDEAL DENDRITIC SNOW GROWTH ZONE/. WIND
FIELDS ARE ALSO IN GOOD AGREEMENT WHICH IS A PLUS WHEN DEALING WITH
LK EFFECT. HAVE LEANED ON BLEND OF HIGHER RESOULTION 5KM NAM AND NCEP
HIGH RES WRF-ARW/NMM FOR POP/QPF DETAILS FOR LK EFFECT. IN REALITY
THIS DID NOT RESULT IN MUCH CHANGE TO PREVIOUS FCST. ONLY EXCEPTION
WAS TO TRIM LK EFFECT POPS BACK OVR MUCH OF GOGEBIC/ONTONAGON/IRON AS
BLYR WINDS ARE NOW NORTHEAST COMPARED TO NORTH. DIFFLUENCE SHOWS UP
IN WINDS OVR WESTERN INTERIOR UPR MI AS WELL...SUGGESTING THAT LK
EFFECT IN THE WEST SHOULD STAY PINNED CLOSER TO LK SUPERIOR SHORE
/KIWD THROUGH PORCUPINE MOUNTAINS AND ALONG SHORE AT ONTONAGON UP
INTO KEWEENAW/.

AT THE SAME TIME...LOW-LEVEL FLOW IS MORE CYCLONIC AND FM THE NNE
OVR NCNTRL CWA FOR MUCH OF THE NIGHT LEADING TO BETTER CHANCE OF
SEEING MODERATE SNOW AMOUNTS. FCST SOUNDINGS SHOW MOISTURE THROUGH H8
/7KFT/ THROUGH ABOUT 09Z THEN MOISTURE SETTLES BLO H85/5KFT TOWARD
DAYBREAK TUESDAY. OVER-WATER INSTABILITY IS SUFFICIENT FOR MODERATE
LAKE EFFECT AS LAKE INDUCED EQL RISE UP OVR 5KFT WITH SFC-H85 DELTA
T/S NEARING 20C. LK EFFECT SNOW PARAMETER PICKS UP ON THIS AND
DEEPER MOISTURE/UNIDIRECTIONAL LOW-LEVEL WINDS WITH POCKET OF HIGHER
VALUES BTWN 03Z AND 09Z TONIGHT. LOCAL LK EFFECT GUIDANCE SUGGESTS
12 HR SNOW AMOUNTS UP TO 6 INCHES IN THIS SETUP. UNDERCUT THIS
SLIGHTLY SINCE IDEAL LK EFFECT CONDITIONS WILL PROBABLY
ONLY BE REALIZED FOR 6-9 HRS DUE TO MARGINAL COLD AIR INITIALLY
TONIGHT AND DEEPER MOISTURE PULLING AWAY IN THE 09Z-12Z PERIOD.
THESE NEGATIVES MAY BE OFFSET BY HIGHER SLR/S AND FLUFFY NATURE OF
THE SNOW SINCE MAJORITY OF MOIST CONVECTIVE LAYER IS IN THE HEART OF
THE DGZ. SNOW RATIOS FM NAM COBB OUTPUT ARE IN THE 20-25:1.

EVEN AS DEEPER MOISTURE LEAVES FIRST THING TUESDAY MORNING...EXPECT
COVERAGE OF SNOW SHOWERS TO REMAIN HIGH THROUGH MOST OF TUESDAY
MORNING THOUGH INTENSITY SHOULD BE KNOCKED DOWN LARGELY DUE TO
INVERSIONS FALLING BLO 4KFT. OVERALL...TOTAL SNOW ACCUMS FM THIS
EVENING THROUGH EARLY TUESDAY AFTN COULD NEAR 6 INCHES IN SPOTS OVR
HIGHER TERRAIN FM HURON MOUNTAINS TO ISHPEMING/NEGAUNEE AND SKANDIA
AREAS AND INTO WESTERN ALGER COUNTY FM DEERTON TO CHATHAM. 12 HR
SNOW AMOUNTS ARE ONLY MARGINALLY SUFFICIENT FOR ADVY THOUGH AND
SINCE THERE IS NOT MUCH FOR ADDITIONAL HAZARDS /CONSIDERABLE BLSN
FOR EXAMPLE/ HAVE HELD OFF ON ISSUING ADVY ATTM. WILL LET DAYSHIFT
TAKE ONE MORE LOOK AT DETAILS AND PUT HEADLINE UP IF NEEDED. NORTH
WINDS BACK MORE NORTHWEST BY LATE TUESDAY AFTN...SHIFTING
DIMINISHING SNOW SHOWERS ACROSS MUCH OF ALGER COUNTY. AWAY FM
LK EFFECT TUESDAY...MAIN ISSUE WILL BE RETURN TO WINTER WITH
TEMPERATURES IN THE TEENS/20S AND WIND CHILL READINGS IN THE
SINGLE DIGITS ABOVE ZERO FOR MUCH OF THE DAY. BASICALLY THAT IS
FAIRLY TYPICAL FOR THIS TIME OF YEAR...BUT GIVEN THE RECENT WARMTH
IT WILL DEFINITELY FEEL ON THE CHILLY SIDE.
&&

.LONG TERM /TUE NIGHT THRU SUN/...

TUE NIGHT...SHRTWV RDG/SFC HI PRES WL DOMINATE. WITH MOCLR SKIES...
LGT WINDS...AND PWAT AS LO AS 0.10-0.15 INCH OR 40-50 PCT OF
NORMAL...EXPECT TEMPS OVER THE INTERIOR SRN TIER TO DIP AOB THE LO
END OF GUIDANCE. AS THE SFC RDG SINKS SLOWLY TO THE S THRU THE
NGT...A STRONGER W WIND WITH H925 WINDS UP TO 30 KTS WL INFLUENCE
AREAS NEAR LK SUP AND LIMIT THE DIURNAL TEMP FALL THERE.

WED...CWA WL BE UNDER STRENGTHENING WLY FLOW/H925 WINDS UP TO 35 KTS
BTWN HI PRES RDG SINKING TOWARD THE OH RIVER VALLEY AND ANOTHER LO
PRES/ATTENDANT COLD FNT TRACKING ACRS NRN ONTARIO ASSOCIATED WITH
SHRTWV WITHIN DEEPENING UPR TROF OVER HUDSON BAY. WITH DRY
AIRMASS/PWAT ARND 0.15 INCH LINGERING...EXPECT A MOSUNNY DAY. H85
TEMPS ARE PROGGED TO REBOUND TO ARND -5C...SO THE DAY WL BE WARMER.
BUT GUSTY W WIND WL MAKE THE AIR FEEL COLDER DESPITE SLOWLY INCRSG
SOLAR ANGLE.

WED NIGHT...COLD FNT ASSOCIATED WITH DEEPENING UPR TROF CENTERED
NEAR HUDSON BAY IS FCST TO DROP INTO NRN LK SUP BY 12Z THU. LACK OF
ANY MSTR INFLOW/DRY NATURE OF ANTECEDENT AIRMASS ARGUES FOR A DRY
FCST WITH LTL IN THE WAY OF PRE-FRONTAL CLD COVER AS WELL...BUT DID
INTRODUCE SOME SCHC POPS OVER THE N HALF OF LK SUP OVERNGT TO MARK
ARRIVAL OF THIS FNT. ALTHOUGH PWAT IS FCST TO REMAIN LO ARND 0.15
INCH...STEADY W WIND WL LIMIT THE DIURNAL FALL OF TEMP.

EXTENDED...MODELS NOW IN GOOD AGREEMENT FOR THU SHOWING A SHARP COLD
FROPA WITH ONLY A WEAK SFC LO RUNNING ALONG THIS BNDRY...IN CONTRAST
TO SOME PAST MODEL RUNS THAT DEPICTED A DEEPER LO. WITH DRY AIRMASS
PRECEDING THE FROPA...WENT NO HIER THAN CHC POPS EVEN NEAR LK SUP.
INFUSION OF MUCH COLDER AIR BEHIND THIS FROPA WITH 00Z GFS SHOWING
H85 TEMPS FALLING AS LO AS -25C AND INVRN BASE ARND 5K FT WL RESULT
IN SOME LES...MOST PREVALENT IN AREAS FAVORED BY FCST NNW FLOW THRU
FRI. TENDED TO GO HIER THAN MODEL CONSENSUS POPS IN THESE FAVORED
AREAS GIVEN TENDENCY FOR MODELS TO UNDERDO LES. THEN AS ARCTIC HI
PRES DRIFTS SEWD TOWARD THE UPR MIDWEST ON SAT...BACKING FLOW TO
MORE W WL SHIFT THE LES INTO AREAS FAVORED BY THAT FLOW. LINGERING
LES SHOULD DIMINISH/END ON SUN AS UPR TROF LIFTS OUT/FLOW TURNS MORE
ACYC WITH HI PRES DRIFTING INTO THE OH RIVER VALLEY. NEAR NORMAL
TEMPS ON THU WL SINK AOB NORMAL THU NGT THRU SAT AS ARCTIC AIRMASS
INVADES THE UPR LKS. TEMPS WL REBOUND ON SUN WITH BLDG UPR RDG INTO
THE GRT LKS/RETURN LLVL SW FLOW OF WARMER AIR TO THE N OF SFC HI IN
THE OH VALLEY.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1222 PM EST MON FEB 6 2012

COLD FRONT DROPPING S OVER LAKE SUPERIOR WILL PASS ACROSS
KCMX/KIWD/KSAW THIS AFTN. UPSLOPE WESTERLY FLOW AHEAD OF FRONT HAS
RESULTED IN IFR CIGS AT KCMX. AS WINDS SHIFT NORTHERLY BEHIND
FRONT...CIGS SHOULD RISE TO MVFR AS IDEAL UPSLOPE COMPONENT IS LOST.
ON THE OTHER HAND...KIWD/KSAW SHOULD SEE LOW MVFR CIGS/POSSIBLE IFR
DEVELOP AS WINDS SHIFT TO AN UPSLOPE NORTHERLY DIRECTION BEHIND
FRONT. A FEW FLURRIES ARE POSSIBLE LATER IN THE AFTN AS AIRMASS
COOLS...BUT LAKE EFFECT -SHSN PROBABLY WON`T DEVELOP UNTIL THE
EVENING WHEN OVERWATER INSTABILITY BECOMES GREATER. NNE FLOW WILL
FAVOR KIWD/KSAW FOR MORE PERSISTENT/HEAVIER SHSN AND LOWER MVFR
CONDITIONS. FLOW IS MOST IDEAL FOR KSAW...AND VIS THERE WILL
PROBABLY DROP TO IFR ON A FREQUENT BASIS THOUGH CIGS MAY STAY AOA
1KFT. DIMINISHING OF LAKE EFFECT SHSN/IMPROVEMENT EXPECTED AT ALL
SITES TUE MORNING AS FLOW BECOMES INCREASINGLY ANTICYCLONIC...
INVERSION FALLS AND DRIER AIR ARRIVES.
&&

.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...

EXPECT W WINDS UP TO 30 KTS EARLY TODAY TO WEAKEN A BIT WITH THE
APPROACH OF A COLD FRONT BUT THEN VEER TO THE N BY THIS EVNG AND
CRANK BACK UP TO 30 KTS FOLLOWING A COLD FRONTAL PASSAGE. THERE MAY
BE SOME GALE FORCE GUSTS TO 35 KTS AS WELL SINCE THE ARRIVAL OF MUCH
COLDER AIR OVER THE RELATIVELY WARM LAKE WATERS ENHANCES MIXING.
HOISTED A HEAVY FREEZING SPRAY WARNING FOR MUCH OF CENTRAL LAKE SUP
WITH INVASION OF ARCTIC AIR/HIER WAVES FORECAST IN THIS AREA INTO
TUE MORNING. THESE AUSTERE CONDITIONS WILL IMPROVE ON TUE WITH THE
ARRIVAL OF A HI PRES RIDGE/LIGHTER WINDS IN THE AFTERNOON. LIGHT
WINDS ON TUE EVENING ASSOCIATED WITH THE PASSING SFC HI PRES RIDGE
WILL INCREASE UP TO 30 KTS BY WED MORNING AS PRES GRADIENT SHARPENS
ONCE THE HI SINKS TOWARD THE OH RIVER VALLEY. THERE MAY BE A FEW
GALE FORCE GUSTS TO 35 KTS OVER THE E WITH LONGER FETCH OF CHILLY
AIR OVER THE RELATIVELY WARM LAKE WATERS ALLOWING FOR MORE MIXING.
ALTHOUGH WINDS MAY DIMINISH LATE WED NIGHT INTO THU FOR A TIME AS
ONLY A WEAK LO PRES CENTER MOVES JUST TO THE NE OF THE LAKE...
EXPECT A STRONGER NNW FLOW TO 30 KTS TO DEVELOP FOLLOWING A COLD
FRONTAL PASSAGE ON THU. THE COMBINATION OF THESE STRONG WINDS AND
THE ARRIVAL OF VERY COLD AIR MAY RESULT IN HEAVY FREEZING SPRAY OVER
PORTIONS OF THE LAKE THRU THU NIGHT. THE CLOSER APPROACH OF A HI
PRES RIDGE WILL BRING DIMINISHING WINDS BY FRI.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
  HEAVY FREEZING SPRAY WARNING FROM 10 PM EST /9 PM CST/ THIS
     EVENING TO 10 AM EST /9 AM CST/ TUESDAY FOR LSZ241>244-263-
     264.

LAKE MICHIGAN...
NONE.
&&

$$

SYNOPSIS...JLA
SHORT TERM...JLA
LONG TERM...KC
AVIATION...ROLFSON
MARINE...KC







AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

 638 AM EST MON FEB 6 2012

LATEST UPDATE...AVIATION...

.SYNOPSIS...(404 AM EST MON FEB 6 2012)
A COLD FRONT WILL CROSS THE REGION TONIGHT.  THIS SYSTEM WILL BRING
VERY LITTLE SNOW...HOWEVER IT WILL RETURN TEMPERATURES TO NEAR
NORMAL VALUES FOR MID WEEK.  ANOTHER SURGE OF COLDER AIR ARRIVES BY
FRIDAY AND INTO THE WEEKEND.  SOME LAKE EFFECT SNOW SHOWERS WILL BE
SEEN ALONG WITH THIS COLDER AIR.

&&

.SHORT TERM...(404 AM EST MON FEB 6 2012)
(TODAY THROUGH WEDNESDAY)
THE SKY FORECAST REMAINS THE BIGGEST CHALLENGE TODAY AND THE
RESULTANT AFFECTS ON THE REGION/S TEMPS.  A LARGE AREA OF STRATUS
COVERED MUCH OF WISCONSIN THIS MORNING AND IT WAS PRESSING EASTWARD
AT A 5-10 MPH PACE.  THAT SPEED ALONG WOULD SUGGEST THAT THE CLOUD
DECK WOULD NOT REACH THE MICHIGAN SHORE UNTIL MID AFTERNOON.
HOWEVER THERE WAS ALSO RANDOM PATCHES OF STRATUS ACROSS LOWER
MICHIGAN TOO.  THE RUC LOW LEVEL MOISTURE PROGS SUGGEST A RAPID
EXPANSION OF THE STRATUS SO THAT THE ENTIRE GRR CWA IS COVERED BY
CLOUDS BY 12Z.  THIS LOOKS UNREASONABLE TO ME.  HOWEVER BELIEVE THE
STRATUS WILL LIKELY SPEED UP IT/S EASTWARD TRACK AS IT MOVES ACROSS
THE LAKE THIS MORNING.  ALSO...THE RANDOM PATCHES MAY ALSO EXPAND
SOMEWHAT THIS MORNING.  BUT THEN THE ISSUE BECOMES...WHAT WILL THE
INCREASED MIXING DO TO THE STRATUS.  I SENSE THAT IT WILL HELP IT TO
ERODE SUCH THAT MUCH OF THE STRATUS BECOMES LESS OF A FACTOR BY MID
DAY.  SO I WILL PLAY THE FORECAST SUCH THAT SOME STRATUS WILL LINGER
THROUGH THE MORNING...BUT WILL BANK ON A MOSTLY SUNNY AFTERNOON AS
THE EASTWARD EDGE OF THE STRATUS MIXES OUT.  IF THIS INDEED OCCURS
TEMPS WILL REACH WELL INTO THE 40S AGAIN TODAY...IF IT DOES NOT
OCCUR TEMPS MAY HOLD FROM 35 TO 40.

THE ARCTIC FRONT IS STILL ON SCHEDULE FOR TONIGHT.  THE LACK OF DEEP
MOISTURE WILL RESULT IN NO SNOW OR PERHAPS A RANDOM FLURRY.  THE LOW
LEVEL FLOW BEHIND THE FRONT SHOULD BE 030-040...KEEPING ANY LAKE
EFFECT ON THE OTHER SIDE OF THE LAKE.  WE WILL HAVE TO KEEP AN EYE
ON POSSIBLE SNOW SHOWERS OFF OF SAGINAW BAY WHICH MAY MOVE INTO
AREAS AROUND ST. JOHNS BY TUESDAY.

HAVE LOW POPS IN FOR TUE AFTERNOON INTO TUESDAY NIGHT FOR AREAS
SOUTH OF I-96.   A SHORT WAVE COMES ACROSS THE LOWER GREAT LAKES AND
COMBINED WITH THE EXITING ARCTIC FRONT MAY PRODUCE SOME LIGHT SNOW.
LOW LEVEL WINDS SHOULD ALSO BACK TO THE NW BY LATE TUESDAY NIGHT
WHICH COULD BRING A FEW SNOW SHOWERS OFF THE LAKE.  BY WEDNESDAY THE
MOISTURE PROFILE BECOMES VERY SHALLOW AS RIDGING BUILDS INTO THE
AREA. EXPECT SUNSHINE WITH NEAR NORMAL TEMPS.

&&

.LONG TERM...(404 AM EST MON FEB 6 2012)
(WEDNESDAY NIGHT THROUGH SUNDAY)
A CLIPPER MOVES ACROSS NORTHERN LOWER MICHIGAN THURSDAY NIGHT
SWINGING AN ARCTIC FRONT SOUTH ACROSS THE FORECAST AREA.

LOOKS LIKE SOME SNOW WILL ACCOMPANY THE FROPA WITH STRONG SFC
CONVERGENCE. LAKE EFFECT BEHIND THE FRONT WILL CONTINUE INTO
SATURDAY BUT FLOW GOES NORTH AND THEN EVENTUALLY NORTHEAST WHICH
WOULD PUSH THE SNOW SHOWERS OFFSHORE. THIS COMBINED WITH INVERSION
HEIGHTS BELOW 10 KFT SHOULD LIMIT ACCUMS...WITH MOST OF THE SNOW
CONCENTRATED FAIRLY CLOSE TO THE LAKE MICHIGAN SHORE.

&&

.AVIATION...(638 AM EST MON FEB 6 2012)
THIN STRATUS WITH MVFR AND PATCHY IFR CEILINGS WILL BE ACROSS LOWER
MICHIGAN THIS MORNING. WILL HAVE A TEMPO GROUP FOR IFR CEILINGS AND
MVFR FOG THROUGH 16Z. SOME THINNING OF THE CLOUDS SHOULD OCCUR BY
AFTERNOON.

A COLD FRONT MOVES IN WITH A THICKER BAND OF CLOUDS AND PERHAPS
FZDZ AFTER MIDNIGHT. DID NOT INCLUDE IN THE FORECAST AT THIS TIME
SINCE PROBABILITY SEEMS LOW.

&&

.MARINE...(404 AM EST MON FEB 6 2012)
SCA IN AFFECT FOR TODAY WITH WSW WINDS TO AROUND 20 KTS.  LOOKS LIKE
WE WILL SEE A BRIEF BREAK IN THE HIGHER WINDS AND WAVES EARLY
TONIGHT AS A COLD FRONT COMES THROUGH.  BUT THEN BEHIND THE FRONT
WAVES SHOULD INCREASE AGAIN LATE TONIGHT OR EARLY TUESDAY IN THE
COLD ADVECTION PATTERN.

&&

.HYDROLOGY...(404 AM EST MON FEB 6 2012)
MINIMAL HYDRO CONCERNS GIVEN THE LACK OF PCPN.  ALSO THE SNOW PACK
TO THE NORTH WILL END IT/S MELTING BY TONIGHT AS THE COLD FRONT
COOLS REGIONAL TEMPS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY ST. JOE TO MANISTEE THROUGH TODAY.

&&

$$

SYNOPSIS:     JK
SHORT TERM:   JK
LONG TERM:    OSTUNO
AVIATION:     OSTUNO
MARINE:       JK
HYDROLOGY:    JK






AREA FORECAST DISCUSSION

NWS GAYLORD MI

 632 AM EST MON FEB 6 2012

.SYNOPSIS.../ISSUED AT 347 AM/

HIGH PRESSURE ACROSS THE REGION THROUGH MIDDAY WILL GIVE WAY TO AN
APPROACHING COLD FRONT BY EVENING. THE PASSAGE OF THIS FRONT WILL
USHER IN A BRIEF SHOT OF MUCH COLDER WEATHER FOR THE DAY ON
TUESDAY...ALONG WITH CHANCES FOR SOME LIGHT SNOW SHOWERS.
TEMPERATURES WILL WARM BACK ABOVE NORMAL BY THURSDAY AS HIGH
PRESSURE AGAIN ARRIVES...BEFORE ANOTHER PUSH OF COLD WEATHER AND
LAKE SNOW SHOWERS ARRIVES FOR FRIDAY INTO THE WEEKEND.

DL

&&

.SHORT TERM.../ISSUED AT 347 AM/...TODAY

A SHARP COLD FRONT IS MOVING SOUTH TOWARD THE NORTH SHORE OF
SUPERIOR EARLY THIS MORNING. THERE IS NO PRECIP...AND IN FACT NO
CLOUDS...WITH THE FRONT ITSELF...THOUGH LOW CLOUDS ARE EXTENSIVE
BEHIND IT. IN THE WARM SECTOR...A FEW PATCHES OF LOW CLOUDS REMAIN
OVER MI AND ENVIRONS...WITH MORE WIDESPREAD CLOUD COVER IN THE UPPER
MS VALLEY AND EXPANDING ESE-WARD. CLOUD/TEMP TRENDS ARE AGAIN
THE MAIN CONCERN TODAY.

COLD FRONT WILL REACH EASTERN UPPER MI TOWARD 18Z...AND WILL BE
NEARING SAGINAW BAY AT 00Z. OUTSIDE OF VERY SHALLOW SURFACE-BASED
MOISTURE...THE DEEP AIRMASS IN THE WARM SECTOR REMAINS VERY DRY
(850-700MB RH LESS THAN 30 PERCENT...PWATS 0.25-0.30). THERE IS NO
RISK OF PRECIP AHEAD OF...OR WITH...THE FRONT. HOWEVER...CLOUD
TRENDS IN THE WARM SECTOR REMAIN PROBLEMATIC. THE AIRMASS BELOW
925MB REMAINS MOIST (SURFACE DEW POINTS REFLECT THIS). LARGER LOW
CLOUD MASS TO OUR WEST IS TRYING TO WORK EAST THIS MORNING...BEFORE
MIXING CAN EAT AWAY AT IT TOO MUCH. DOWNSLOPING WINDS INTO FAR
EASTERN WI ARE KEEPING THE CLOUD MASS FROM ADVANCING AS FAR EAST AS
IT COULD. MODEL GUIDANCE IS ALL OVER THE MAP...FROM THE NAM NOT
ALLOWING ANY LOW CLOUDS TO CROSS THE LAKE...TO THE HRRR WHICH
COMPLETELY SOCKS IN ALL OF NORTHERN MI BY 16Z.

GIVEN SATELLITE TRENDS OF AN CLOUD MASS CLEARLY STRUGGLING TO MOVE
EAST...WILL NOT BRING IN OVERCAST SKIES THIS MORNING. WE/RE STILL
PLENTY MOIST DOWN LOW...AND SMALL PATCHES OF LOW CLOUDS COULD FORM
JUST ABOUT ANYWHERE THIS MORNING. WE MAY ALSO BE NEED MOIST ENOUGH
TO QUICKLY FIRE A SHALLOW CU DECK BEFORE MIXING IT OUT TOWARD
MIDDAY.

BEHIND THE FRONT...LOW CLOUDS WILL BECOME EXTENSIVE FROM NORTH TO
SOUTH DURING THE AFTERNOON. THERE MAY BE AN OUTSIDE SHOT AT A BIT OF
DRIZZLE OR SOME FLURRIES IN CENTRAL/WESTERN CHIPPEWA CO VERY LATE.
INVERSION-TOP (875MB) TEMPS REACH -7/8C (SO DELTA T/S INTO THE LOWER
TEENS).

MAX TEMPS WILL AGAIN BE QUITE MILD. WILL FAVOR WARMER GUIDANCE
NUMBERS GIVEN A BALMY START TO THE DAY. MAX TEMPS MID/UPPER 30S
NORTH TO MID 40S FAR SE.

JZ

&&

.LONG TERM.../ISSUED AT 347 AM/...TONIGHT AND BEYOND

THE UPPER TROF FORCING TODAY/S COLD FRONT WON/T ACTUALLY MAKE IT TO
OUR NEIGHBORHOOD UNTIL LATE TUESDAY. LOW LEVEL COLD ADVECTION WILL
CONTINUE UNTIL THEN (THOUGH THE AIRMASS SHOULD MODERATE WITH SOME
SUNSHINE TUESDAY). DESPITE REASONABLE INSTABILITY...THE POOR NORTH
FETCH...LACK OF MOISTURE...AND ARRIVAL OF SURFACE RIDGING/
ANTICYCLONIC CURVATURE WILL LIMIT LAKE EFFECT SNOW (LES) POTENTIAL.
AS HIGH PRESSURE PRESSES SOUTH INTO THE CENTRAL PLAINS BY
WEDNESDAY...WESTERLY LOW LEVEL FLOW AND WARM ADVECTION WILL AGAIN BE
RE-ESTABLISHED HERE. THAT WILL BE BRIEF...AS A STRONGER SHOT OF COLD
AIR APPEARS LIKELY AT THE END OF THE WORK WEEK. TEMP/PRECIP
TRENDS...MAINLY ASSOCIATED WITH THE COLD AIR TONIGHT/TUESDAY AND
AGAIN AT THE END OF THE WEEK...ARE THE MAIN CONCERNS.

TONIGHT...COLD FRONT WILL MOVE SOUTH OF MI...WHILE 500MB TROF WILL
ADVANCE TO NORTHERN SUPERIOR. SURFACE HIGH PRESSURE WILL MOVE INTO
ND...WITH RIDGING EXTENDING JUST NORTH OF SUPERIOR. 1000-850MB WINDS
WILL BECOME N/NNW BY 03Z...AND N/NNE BY 12Z. WE DO MANAGE TO GET
850-700MB RH LEVELS UP TO 60 PERCENT OR SO...IN THE EVENING AROUND
EASTERN UPPER...EXPANDING SOUTH OVERNIGHT (DRYING OUT ON EASTERN
SUPERIOR TOWARD 12Z). DELTA T/S REACH IN THE MID TEENS IN THE
OVERNIGHT HOURS...WHICH SHOULD SPOT OUT A FEW SNOW SHOWERS IN FAR
WESTERN AND FAR EASTERN SECTIONS OF THE FORECAST AREA (GIVEN
UNFAVORABLE N FETCH). WILL KEEP POPS QUITE SMALL...NAM/LOCAL WRF IN
EXCELLENT AGREEMENT IN GENERATING NO QPF ANYWHERE IN THE FORECAST
AREA TONIGHT. MEANWHILE...THE I-75/US-127 CORRIDOR IN NORTHERN
LOWER...AND FAR EASTERN UPPER...SHOULD CLEAR PARTIAL CLEARING. MIN
TEMPS WILL RANGE FROM MID/UPPER SINGLE DIGITS IN FAR EASTERN
UPPER...TO LOWER 20S IN SOME SOUTHERN SECTIONS.

TUESDAY...THE MAIN FACTOR IS THE STRONG SURFACE RIDGE THAT CROSSES
SUPERIOR AND SETTLES ACROSS UPPER/FAR NORTHERN LOWER MI BY 00Z.
ASSOCIATED DRYING (850-700MB RH GO BELOW 25 PERCENT) AND
ANTICYCLONICALLY CURVED FLOW WILL COMPLETELY PUT THE KIBOSH ON LES
AS THE DAY PROCEEDS...DESPITE CONTINUED PRESENCE OF CHILLY AIR
(DELTA T/S MID TEENS). EXPECT CLOUD COVER TO ERODE AS WELL AS WE
MOVE THRU THE AFTERNOON. WILL CONTINUE WITH A SMALL CHANCE OF -SHSN
IN THE MORNING ALONG WESTERN AND EASTERN FRINGES OF THE FORECAST
AREA...AND GO DRY IN THE AFTERNOON. MAX TEMPS UPPER TEENS TO MID 20S.

TUE NIGHT THRU WED NIGHT...SURFACE RIDGE AXIS WILL CONTINUE TO MOVE
SOUTH ACROSS LOWER MI TUESDAY NIGHT...AND WILL EVENTUALLY REACH THE
OHIO VALLEY BY THURSDAY MORNING. BY THEN...THE NEXT COLD FRONT WILL
BE REACHING SUPERIOR. IN BETWEEN...WESTERLY 1000-850MB WINDS WILL
KICK THE COLD AIR OUT FOR A BIT...WITH 850MB TEMPS REACHING -6C BY
WEDNESDAY EVENING. THIS AIRMASS WILL REMAIN QUITE DRY IN THE MID AND
UPPER LEVELS...THOUGH WE MAY AGAIN BE CONTENDING WITH OCCASIONAL LOW
CLOUD ISSUES (ESPECIALLY WEDNESDAY NIGHT) LIKE WE/VE SEEN THE LAST
SEVERAL DAYS. STILL...PARTLY CLOUDY TO MOSTLY CLEAR WILL COVER MUCH
OF THESE PERIODS...WITH NO RISK FOR PRECIP. MIN TEMPS WILL BE QUITE
CHILLY TUE NIGHT...SINGLE DIGITS TO MID TEENS. MAX TEMPS WEDNESDAY
MID 20S TO LOWER 30S. MIN TEMPS WED NIGHT MID TEENS TO LOWER 20S.

JZ

LATER PERIODS (THURSDAY THROUGH SUNDAY)...BRIEF PATTERN CHANGE STILL
ANTICIPATED HEADING INTO THE WEEKEND...AS STRONG MERIDIONAL RIDGING
BUILDING UP THE WEST COAST OF NORTH AMERICA BRIEFLY DISLODGES THE
POLAR VORTEX TOWARD HUDSON BAY. HOWEVER...AS MENTIONED IN THIS SPACE
SEVERAL TIMES THE PAST FEW DAYS...THE PATTERN CHANGE STILL LOOKS TO
BE VERY BRIEF...WITH THE COLDEST AIR RELEGATED TO FRIDAY AND
SATURDAY DAY WHEN H8 TEMPS ARE STILL PROGGED BY MAJORITY OF 00Z
GUIDANCE TO DIP TO AROUND -21C OR SO AT THEIR COLDEST. OVERALL
HEMISPHERIC PATTERN DURING THE WEEKEND TIMEFRAME IS RATHER
UNSTABLE...FEATURING A WAVERING 3-4 WAVE PATTERN...AND THUS NO REAL
SURPRISE TO SEE GUIDANCE CONTINUING EARLIER TRENDS OF ERASING THE
BRIEF PATTERN SHIFT AS STRONG PACIFIC JET ENERGY AGAIN PLOWS THROUGH
MUCH OF THE CONUS. THIS SHOULD RAPIDLY SHIFT THE CORE OF COLDEST AIR
TO THE EAST BY SUNDAY...WITH THE STRONG POSSIBILITY FOR ANOTHER
ROUND OF QUITE WARM WEATHER (BY FEBRUARY STANDARDS AT LEAST) TO
ARRIVE INTO THE FOLLOWING WEEK...THOUGH THAT`S GETTING A BIT AHEAD
OF THINGS FOR THIS FCST.

LOOKING AT THE SPECIFICS...STILL LOOKS LIKE A PERIOD OF SOME LAKE
EFFECT SNOW SHOWERS (BASICALLY A GIVEN) AS COLDER AIR POURS INTO THE
AREA LATER THURSDAY THROUGH SATURDAY...WITH TRENDS THE PAST FEW DAYS
STILL SUGGESTING A MEAN NORTHERLY COMPONENT TO THE LOW LEVEL FLOW.
THAT SAID...MESOSCALE PROCESSES MAY INCREASINGLY COME INTO PLAY BY
SATURDAY AS LOW LEVEL FLOW BECOMES INCREASINGLY ANTICYCLONIC BUT
OVERLAKE INSTABILITY REMAINS STELLAR. WHILE OVERALL MOISTURE
PROFILES DURING THE FRIDAY/SATURDAY TIMEFRAME ARE NOTHING REALLY
IMPRESSIVE...DEPTH OF THE DGZ THROUGH THE LAKE-INDUCED CLOUD LAYER
DOES ARGUE THAT SOME LOCALIZED MODEST FLUFFY ACCUMULATIONS WILL BE
POSSIBLE...MAINLY DOWNWIND OF GRAND TRAVERSE BAY AND PERHAPS INTO
FAR NORTHWESTERN CHIPPEWA COUNTY. SNOW SHOWER CHANCES WILL DWINDLE
QUICKLY HEADING THROUGH THE DAY ON SUNDAY AS LOW LEVEL INSTABILITY
WANES...WITH AN OVERWHELMING MAJORITY OF GUIDANCE SIGNALS SUGGESTING
H8 TEMPS MODIFY INTO THE SINGLE DIGITS BELOW ZERO BY 00Z MONDAY.
TEMPS THROUGH THE EXTENDED WILL FINALLY BE A BIT BELOW NORMAL FOR
ONCE.

LAWRENCE

&&

.MARINE.../ISSUED AT 347 AM/

SOMEWHAT BLUSTERY WEST WINDS WILL CONTINUE UNTIL A COLD FRONT...NOW
NEARING SUPERIOR...CROSSES NORTHERN MI THIS AFTERNOON AND EARLY
EVENING. SMALL CRAFT ADVISORIES ALREADY UP FOR ALL WATERS...AND WILL
REMAIN UNCHANGED. COLD NORTH WINDS MAY SUPPORT ADVISORIES INTO
TONIGHT (ESPECIALLY AS INSTABILITY INCREASES)...BUT WILL HOLD OFF ON
ANY EXTENSIONS AT THIS TIME.

JZ

&&

.AVIATION.../ISSUED AT 632 AM/...VALID FOR 12Z TAFS

LOW CLOUDS (MVFR) ARE REDEVELOPING RIGHT OVER MBL...AND WILL BE
SKIRTING BY TVC AS WELL THIS MORNING. OTHERWISE...CONDITIONS WILL BE
VFR TODAY UNTIL MID AFTERNOON...WHEN A COLD FRONT INVADES FROM THE
NORTH. MVFR CLOUDS WILL BE WIDESPREAD BEHIND THE FRONT...EXPANDING
INTO ALL TAF SITES BY EARLY EVENING...AND LASTING THRU TONIGHT.

JZ

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR
     LHZ345>349.
LM...SMALL CRAFT ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR
     LMZ323-341-342-344>346.
LS...NONE.

&&

$$







AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 623 AM EST MON FEB 6 2012

UPDATED AVIATION DISCUSSION FOR 12Z TAFS

.SYNOPSIS...

IN CONTRAST TO LAST COUPLE NIGHTS...CLEAR SKIES ARE DOMINANT ACROSS
UPR MI THIS MORNING. STRATUS IS NOT TOO FAR AWAY THOUGH OVR MN AND
WI. SO FAR...THERE IS ENOUGH WIND OVR UPR MI TO PROHIBIT THE STRATUS
FM SURGING INTO UPR MI. COLD FRONT THAT WILL BRING A CHANGE TO THE
RECENT UNSEAONABLE WARMTH IS DROPPING ACROSS MANITOBA AND ONTARIO
THIS MORNING. STRATOCU IS INITIAL SIGN OF THE COLDER AIR WITH SFC
OBS TURNING UP SOME LGT SNOW BEHIND THE FRONT OVR NORTHERN ONTARIO.
COLDER AIR ARRIVING LATE TODAY AND TONIGHT WILL LEAD TO LK EFFECT
SNOW SHOWERS OVR NORTHERN UPR MI. AS HAS BEEN CASE MUCH OF THIS
WINTER...THIS COOL DOWN WILL BE BRIEF WITH TEMPERATURES MOVING BACK
TOWARD NORMAL AS SOON AS WEDNESDAY. APPEARS THAT MORE SUBSTANTIAL
COOL DOWN WILL RETURN BY LATE WEEK INTO THE WEEKEND AS PORTION OF
POLAR VORTEX OVER EASTERN CANADA SLIDES INTO GREAT LAKES/NORTHEAST
CONUS.
&&

.SHORT TERM /TODAY THROUGH TUESDAY/...

IN THE NEAR TERM...QUIET CONDITIONS AS SKIES SHOULD STAY MOSTLY
CLEAR. RUC13 PERFORMED WELL WITH STRATUS YDY...AND IT DOES INDICATE
STRATUS MAY TRY TO MAKE MOVE INTO SW FRINGES OF UPR MI FM WISCONSIN.
SINCE RUC13 IS OVERDOING NORTHERN EXTENT TO CLOUDS AT THIS HOUR...WILL
KEEP WITH MAINLY CLEAR SKIES. DESPITE THE CLEAR SKIES...TEMPS ARE
STILL IN THE UPR 20S TO LOWER AND EVEN MID 30S WITH STEADY WEST WINDS
BLOWING AHEAD OF COLD FRONT DROPPING ACROSS ONTARIO. ISOLATED INLAND
LOCATIONS WHERE WINDS GO CALM COULD STILL FALL TO LOW-MID 20S THROUGH
SUNRISE /ALREADY HAVE SOME 25F READINGS AT WAKEFIELD AND DOE
LAKE/...BUT FOR LARGE PART TEMPS WILL REMAIN STEADY ELSEWHERE.

TODAY...
COLD FRONT FCST TO MOVE INTO FAR NORTH CWA TOWARD MIDDAY. FRONT
SHOULD REACH SOUTHERN CWA AROUND KMNM BY 21Z THIS AFTN. STRATOCU MAIN
ISSUE INITIALLY AS THERE IS NOT A LOT OF COLD AIR AROUND JUST IN WAKE
OF FRONT...WITH H85 TEMPS WARMER THAN -8C. KEPT ISOLATED SNOW SHOWERS
RESTRICTED TO NW CWA THIS AFTN AS COOLER AIR GRADUALLY FILTERS INTO
UPR MI. OTHERWISE...BASED ON UPSTREAM TRENDS IN ONTARIO THIS
MORNING...MOST AREAS COULD SEE SOME FLURRIES JUST IN WAKE OF FROPA.
TEMPS SHOULD FALL OFF WITH PASSAGE OF FROPA...BUT DOES APPEAR THAT
SHARPER COOLING IS LAGGING INITIAL SURGE OF STRATOCU BY A FEW HOURS.
HEADED TOWARD REGIONAL CANADIAN FOR TEMPERATURE TRENDS TODAY. BASED
ON WARM START THIS MORNING AND WEST WINDS ALREADY STIRRING...SEEMS
LIKELY THAT DOWNSLOPE AREAS OF CNTRL /MARQUETTE TO ESCANABA TO
MENOMINEE/ HAVE SHOT TO REACH INTO 40S BY EARLY AFTN JUST AHEAD OF
FRONT. BY LATE AFTN...EXPECT MOST AREAS TO BE AT OR BLO
FREEZING...WITH 20S LIKELY IN THE HIGHER TERRAIN OF NW AND NCNTRL UPR
MI.

TONIGHT INTO TUESDAY...
REALLY GOOD AGREEMENT ON SPECIFICS FM 00Z GUIDANCE WITH EXTENT AND
DEPTH OF COLD AIR /H85 TEMPS AROUND -15C/ AND MOISTURE /AT LEAST UP
TO 5KFT WHICH INTERSECTS IDEAL DENDRITIC SNOW GROWTH ZONE/. WIND
FIELDS ARE ALSO IN GOOD AGREEMENT WHICH IS A PLUS WHEN DEALING WITH
LK EFFECT. HAVE LEANED ON BLEND OF HIGHER RESOULTION 5KM NAM AND NCEP
HIGH RES WRF-ARW/NMM FOR POP/QPF DETAILS FOR LK EFFECT. IN REALITY
THIS DID NOT RESULT IN MUCH CHANGE TO PREVIOUS FCST. ONLY EXCEPTION
WAS TO TRIM LK EFFECT POPS BACK OVR MUCH OF GOGEBIC/ONTONAGON/IRON AS
BLYR WINDS ARE NOW NORTHEAST COMPARED TO NORTH. DIFFLUENCE SHOWS UP
IN WINDS OVR WESTERN INTERIOR UPR MI AS WELL...SUGGESTING THAT LK
EFFECT IN THE WEST SHOULD STAY PINNED CLOSER TO LK SUPERIOR SHORE
/KIWD THROUGH PORCUPINE MOUNTAINS AND ALONG SHORE AT ONTONAGON UP
INTO KEWEENAW/.

AT THE SAME TIME...LOW-LEVEL FLOW IS MORE CYCLONIC AND FM THE NNE
OVR NCNTRL CWA FOR MUCH OF THE NIGHT LEADING TO BETTER CHANCE OF
SEEING MODERATE SNOW AMOUNTS. FCST SOUNDINGS SHOW MOISTURE THROUGH H8
/7KFT/ THROUGH ABOUT 09Z THEN MOISTURE SETTLES BLO H85/5KFT TOWARD
DAYBREAK TUESDAY. OVER-WATER INSTABILITY IS SUFFICIENT FOR MODERATE
LAKE EFFECT AS LAKE INDUCED EQL RISE UP OVR 5KFT WITH SFC-H85 DELTA
T/S NEARING 20C. LK EFFECT SNOW PARAMETER PICKS UP ON THIS AND
DEEPER MOISTURE/UNIDIRECTIONAL LOW-LEVEL WINDS WITH POCKET OF HIGHER
VALUES BTWN 03Z AND 09Z TONIGHT. LOCAL LK EFFECT GUIDANCE SUGGESTS
12 HR SNOW AMOUNTS UP TO 6 INCHES IN THIS SETUP. UNDERCUT THIS
SLIGHTLY SINCE IDEAL LK EFFECT CONDITIONS WILL PROBABLY
ONLY BE REALIZED FOR 6-9 HRS DUE TO MARGINAL COLD AIR INITIALLY
TONIGHT AND DEEPER MOISTURE PULLING AWAY IN THE 09Z-12Z PERIOD.
THESE NEGATIVES MAY BE OFFSET BY HIGHER SLR/S AND FLUFFY NATURE OF
THE SNOW SINCE MAJORITY OF MOIST CONVECTIVE LAYER IS IN THE HEART OF
THE DGZ. SNOW RATIOS FM NAM COBB OUTPUT ARE IN THE 20-25:1.

EVEN AS DEEPER MOISTURE LEAVES FIRST THING TUESDAY MORNING...EXPECT
COVERAGE OF SNOW SHOWERS TO REMAIN HIGH THROUGH MOST OF TUESDAY
MORNING THOUGH INTENSITY SHOULD BE KNOCKED DOWN LARGELY DUE TO
INVERSIONS FALLING BLO 4KFT. OVERALL...TOTAL SNOW ACCUMS FM THIS
EVENING THROUGH EARLY TUESDAY AFTN COULD NEAR 6 INCHES IN SPOTS OVR
HIGHER TERRAIN FM HURON MOUNTAINS TO ISHPEMING/NEGAUNEE AND SKANDIA
AREAS AND INTO WESTERN ALGER COUNTY FM DEERTON TO CHATHAM. 12 HR
SNOW AMOUNTS ARE ONLY MARGINALLY SUFFICIENT FOR ADVY THOUGH AND
SINCE THERE IS NOT MUCH FOR ADDITIONAL HAZARDS /CONSIDERABLE BLSN
FOR EXAMPLE/ HAVE HELD OFF ON ISSUING ADVY ATTM. WILL LET DAYSHIFT
TAKE ONE MORE LOOK AT DETAILS AND PUT HEADLINE UP IF NEEDED. NORTH
WINDS BACK MORE NORTHWEST BY LATE TUESDAY AFTN...SHIFTING
DIMINISHING SNOW SHOWERS ACROSS MUCH OF ALGER COUNTY. AWAY FM
LK EFFECT TUESDAY...MAIN ISSUE WILL BE RETURN TO WINTER WITH
TEMPERATURES IN THE TEENS/20S AND WIND CHILL READINGS IN THE
SINGLE DIGITS ABOVE ZERO FOR MUCH OF THE DAY. BASICALLY THAT IS
FAIRLY TYPICAL FOR THIS TIME OF YEAR...BUT GIVEN THE RECENT WARMTH
IT WILL DEFINITELY FEEL ON THE CHILLY SIDE.

.LONG TERM /TUE NIGHT THRU SUN/...

TUE NIGHT...SHRTWV RDG/SFC HI PRES WL DOMINATE. WITH MOCLR SKIES...
LGT WINDS...AND PWAT AS LO AS 0.10-0.15 INCH OR 40-50 PCT OF
NORMAL...EXPECT TEMPS OVER THE INTERIOR SRN TIER TO DIP AOB THE LO
END OF GUIDANCE. AS THE SFC RDG SINKS SLOWLY TO THE S THRU THE
NGT...A STRONGER W WIND WITH H925 WINDS UP TO 30 KTS WL INFLUENCE
AREAS NEAR LK SUP AND LIMIT THE DIURNAL TEMP FALL THERE.

WED...CWA WL BE UNDER STRENGTHENING WLY FLOW/H925 WINDS UP TO 35 KTS
BTWN HI PRES RDG SINKING TOWARD THE OH RIVER VALLEY AND ANOTHER LO
PRES/ATTENDANT COLD FNT TRACKING ACRS NRN ONTARIO ASSOCIATED WITH
SHRTWV WITHIN DEEPENING UPR TROF OVER HUDSON BAY. WITH DRY
AIRMASS/PWAT ARND 0.15 INCH LINGERING...EXPECT A MOSUNNY DAY. H85
TEMPS ARE PROGGED TO REBOUND TO ARND -5C...SO THE DAY WL BE WARMER.
BUT GUSTY W WIND WL MAKE THE AIR FEEL COLDER DESPITE SLOWLY INCRSG
SOLAR ANGLE.

WED NIGHT...COLD FNT ASSOCIATED WITH DEEPENING UPR TROF CENTERED
NEAR HUDSON BAY IS FCST TO DROP INTO NRN LK SUP BY 12Z THU. LACK OF
ANY MSTR INFLOW/DRY NATURE OF ANTECEDENT AIRMASS ARGUES FOR A DRY
FCST WITH LTL IN THE WAY OF PRE-FRONTAL CLD COVER AS WELL...BUT DID
INTRODUCE SOME SCHC POPS OVER THE N HALF OF LK SUP OVERNGT TO MARK
ARRIVAL OF THIS FNT. ALTHOUGH PWAT IS FCST TO REMAIN LO ARND 0.15
INCH...STEADY W WIND WL LIMIT THE DIURNAL FALL OF TEMP.

EXTENDED...MODELS NOW IN GOOD AGREEMENT FOR THU SHOWING A SHARP COLD
FROPA WITH ONLY A WEAK SFC LO RUNNING ALONG THIS BNDRY...IN CONTRAST
TO SOME PAST MODEL RUNS THAT DEPICTED A DEEPER LO. WITH DRY AIRMASS
PRECEDING THE FROPA...WENT NO HIER THAN CHC POPS EVEN NEAR LK SUP.
INFUSION OF MUCH COLDER AIR BEHIND THIS FROPA WITH 00Z GFS SHOWING
H85 TEMPS FALLING AS LO AS -25C AND INVRN BASE ARND 5K FT WL RESULT
IN SOME LES...MOST PREVALENT IN AREAS FAVORED BY FCST NNW FLOW THRU
FRI. TENDED TO GO HIER THAN MODEL CONSENSUS POPS IN THESE FAVORED
AREAS GIVEN TENDENCY FOR MODELS TO UNDERDO LES. THEN AS ARCTIC HI
PRES DRIFTS SEWD TOWARD THE UPR MIDWEST ON SAT...BACKING FLOW TO
MORE W WL SHIFT THE LES INTO AREAS FAVORED BY THAT FLOW. LINGERING
LES SHOULD DIMINISH/END ON SUN AS UPR TROF LIFTS OUT/FLOW TURNS MORE
ACYC WITH HI PRES DRIFTING INTO THE OH RIVER VALLEY. NEAR NORMAL
TEMPS ON THU WL SINK AOB NORMAL THU NGT THRU SAT AS ARCTIC AIRMASS
INVADES THE UPR LKS. TEMPS WL REBOUND ON SUN WITH BLDG UPR RDG INTO
THE GRT LKS/RETURN LLVL SW FLOW OF WARMER AIR TO THE N OF SFC HI IN
THE OH VALLEY.
&&

.AVIATION /FOR THE 12Z TAF ISSUANCE/...

COLD FRONT OVER ONTARIO DROPS ACROSS ALL TAF SITES TODAY. BASED ON
UPSTREAM TRENDS EXPECT VFR CIGS FOR A COUPLE HOURS INITIALLY FOLLOWED
BY CIGS LOWERING BLO 2KFT WITH SOME FLURRIES. WILD CARD THIS MORNING
IS BATCH OF LOW-LEVEL MOISTURE SEEN ON SATELLITE FM WEST OF THUNDER
BAY ONTARIO TOWARD SAULT STE MARIE. RECENTLY HAVE BEEN SOME HINTS
THAT THIS COULD EXPAND OVER NORTHERN UPR MI BY MID-LATE MORNING.
HAVE PUT SOME MENTION OF SCT BLO 010 IN TAFS AT CMX AND SAW. AT
THIS POINT...HAVE LOW CONFIDENCE IN THIS TURNING INTO A LOW CIG THIS
MORNING IS LOW...BUT WILL BE SOMETHING TO MONITOR. LK EFFECT SHOULD
DEVELOP LATE TODAY INTO TONIGHT AT ALL THREE TAF SITES. EXPECT VSBY
REDUCTION IN SNOW SHOWERS AND SOME BLOWING SNOW...ESPECIALLY AT KIWD
AND KSAW WITH FAVORED NORTH TO NORTHEAST WINDS. IFR VSBY IS POSSIBLE
BUT THINK CIGS WILL REMAIN AOA 1KFT.
&&

.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...

EXPECT W WINDS UP TO 30 KTS EARLY TODAY TO WEAKEN A BIT WITH THE
APPROACH OF A COLD FRONT BUT THEN VEER TO THE N BY THIS EVNG AND
CRANK BACK UP TO 30 KTS FOLLOWING A COLD FRONTAL PASSAGE. THERE MAY
BE SOME GALE FORCE GUSTS TO 35 KTS AS WELL SINCE THE ARRIVAL OF MUCH
COLDER AIR OVER THE RELATIVELY WARM LAKE WATERS ENHANCES MIXING.
HOISTED A HEAVY FREEZING SPRAY WARNING FOR MUCH OF CENTRAL LAKE SUP
WITH INVASION OF ARCTIC AIR/HIER WAVES FORECAST IN THIS AREA INTO
TUE MORNING. THESE AUSTERE CONDITIONS WILL IMPROVE ON TUE WITH THE
ARRIVAL OF A HI PRES RIDGE/LIGHTER WINDS IN THE AFTERNOON. LIGHT
WINDS ON TUE EVENING ASSOCIATED WITH THE PASSING SFC HI PRES RIDGE
WILL INCREASE UP TO 30 KTS BY WED MORNING AS PRES GRADIENT SHARPENS
ONCE THE HI SINKS TOWARD THE OH RIVER VALLEY. THERE MAY BE A FEW
GALE FORCE GUSTS TO 35 KTS OVER THE E WITH LONGER FETCH OF CHILLY
AIR OVER THE RELATIVELY WARM LAKE WATERS ALLOWING FOR MORE MIXING.
ALTHOUGH WINDS MAY DIMINISH LATE WED NIGHT INTO THU FOR A TIME AS
ONLY A WEAK LO PRES CENTER MOVES JUST TO THE NE OF THE LAKE...
EXPECT A STRONGER NNW FLOW TO 30 KTS TO DEVELOP FOLLOWING A COLD
FRONTAL PASSAGE ON THU. THE COMBINATION OF THESE STRONG WINDS AND
THE ARRIVAL OF VERY COLD AIR MAY RESULT IN HEAVY FREEZING SPRAY OVER
PORTIONS OF THE LAKE THRU THU NIGHT. THE CLOSER APPROACH OF A HI
PRES RIDGE WILL BRING DIMINISHING WINDS BY FRI.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
  HEAVY FREEZING SPRAY WARNING FROM 10 PM EST /9 PM CST/ THIS
     EVENING TO 10 AM EST /9 AM CST/ TUESDAY FOR LSZ241>244-263-
     264.

LAKE MICHIGAN...
NONE.
&&

$$

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





AREA FORECAST DISCUSSION

NWS MARQUETTE MI

 421 AM EST MON FEB 6 2012

.SYNOPSIS...

IN CONTRAST TO LAST COUPLE NIGHTS...CLEAR SKIES ARE DOMINANT ACROSS
UPR MI THIS MORNING. STRATUS IS NOT TOO FAR AWAY THOUGH OVR MN AND
WI. SO FAR...THERE IS ENOUGH WIND OVR UPR MI TO PROHIBIT THE STRATUS
FM SURGING INTO UPR MI. COLD FRONT THAT WILL BRING A CHANGE TO THE
RECENT UNSEAONABLE WARMTH IS DROPPING ACROSS MANITOBA AND ONTARIO
THIS MORNING. STRATOCU IS INITIAL SIGN OF THE COLDER AIR WITH SFC
OBS TURNING UP SOME LGT SNOW BEHIND THE FRONT OVR NORTHERN ONTARIO.
COLDER AIR ARRIVING LATE TODAY AND TONIGHT WILL LEAD TO LK EFFECT
SNOW SHOWERS OVR NORTHERN UPR MI. AS HAS BEEN CASE MUCH OF THIS
WINTER...THIS COOL DOWN WILL BE BRIEF WITH TEMPERATURES MOVING BACK
TOWARD NORMAL AS SOON AS WEDNESDAY. APPEARS THAT MORE SUBSTANTIAL
COOL DOWN WILL RETURN BY LATE WEEK INTO THE WEEKEND AS PORTION OF
POLAR VORTEX OVER EASTERN CANADA SLIDES INTO GREAT LAKES/NORTHEAST
CONUS.
&&

.SHORT TERM /TODAY THROUGH TUESDAY/...

IN THE NEAR TERM...QUIET CONDITIONS AS SKIES SHOULD STAY MOSTLY
CLEAR. RUC13 PERFORMED WELL WITH STRATUS YDY...AND IT DOES INDICATE
STRATUS MAY TRY TO MAKE MOVE INTO SW FRINGES OF UPR MI FM WISCONSIN.
SINCE RUC13 IS OVERDOING NORTHERN EXTENT TO CLOUDS AT THIS HOUR...WILL
KEEP WITH MAINLY CLEAR SKIES. DESPITE THE CLEAR SKIES...TEMPS ARE
STILL IN THE UPR 20S TO LOWER AND EVEN MID 30S WITH STEADY WEST WINDS
BLOWING AHEAD OF COLD FRONT DROPPING ACROSS ONTARIO. ISOLATED INLAND
LOCATIONS WHERE WINDS GO CALM COULD STILL FALL TO LOW-MID 20S THROUGH
SUNRISE /ALREADY HAVE SOME 25F READINGS AT WAKEFIELD AND DOE
LAKE/...BUT FOR LARGE PART TEMPS WILL REMAIN STEADY ELSEWHERE.

TODAY...
COLD FRONT FCST TO MOVE INTO FAR NORTH CWA TOWARD MIDDAY. FRONT
SHOULD REACH SOUTHERN CWA AROUND KMNM BY 21Z THIS AFTN. STRATOCU MAIN
ISSUE INITIALLY AS THERE IS NOT A LOT OF COLD AIR AROUND JUST IN WAKE
OF FRONT...WITH H85 TEMPS WARMER THAN -8C. KEPT ISOLATED SNOW SHOWERS
RESTRICTED TO NW CWA THIS AFTN AS COOLER AIR GRADUALLY FILTERS INTO
UPR MI. OTHERWISE...BASED ON UPSTREAM TRENDS IN ONTARIO THIS
MORNING...MOST AREAS COULD SEE SOME FLURRIES JUST IN WAKE OF FROPA.
TEMPS SHOULD FALL OFF WITH PASSAGE OF FROPA...BUT DOES APPEAR THAT
SHARPER COOLING IS LAGGING INITIAL SURGE OF STRATOCU BY A FEW HOURS.
HEADED TOWARD REGIONAL CANADIAN FOR TEMPERATURE TRENDS TODAY. BASED
ON WARM START THIS MORNING AND WEST WINDS ALREADY STIRRING...SEEMS
LIKELY THAT DOWNSLOPE AREAS OF CNTRL /MARQUETTE TO ESCANABA TO
MENOMINEE/ HAVE SHOT TO REACH INTO 40S BY EARLY AFTN JUST AHEAD OF
FRONT. BY LATE AFTN...EXPECT MOST AREAS TO BE AT OR BLO
FREEZING...WITH 20S LIKELY IN THE HIGHER TERRAIN OF NW AND NCNTRL UPR
MI.

TONIGHT INTO TUESDAY...
REALLY GOOD AGREEMENT ON SPECIFICS FM 00Z GUIDANCE WITH EXTENT AND
DEPTH OF COLD AIR /H85 TEMPS AROUND -15C/ AND MOISTURE /AT LEAST UP
TO 5KFT WHICH INTERSECTS IDEAL DENDRITIC SNOW GROWTH ZONE/. WIND
FIELDS ARE ALSO IN GOOD AGREEMENT WHICH IS A PLUS WHEN DEALING WITH
LK EFFECT. HAVE LEANED ON BLEND OF HIGHER RESOULTION 5KM NAM AND NCEP
HIGH RES WRF-ARW/NMM FOR POP/QPF DETAILS FOR LK EFFECT. IN REALITY
THIS DID NOT RESULT IN MUCH CHANGE TO PREVIOUS FCST. ONLY EXCEPTION
WAS TO TRIM LK EFFECT POPS BACK OVR MUCH OF GOGEBIC/ONTONAGON/IRON AS
BLYR WINDS ARE NOW NORTHEAST COMPARED TO NORTH. DIFFLUENCE SHOWS UP
IN WINDS OVR WESTERN INTERIOR UPR MI AS WELL...SUGGESTING THAT LK
EFFECT IN THE WEST SHOULD STAY PINNED CLOSER TO LK SUPERIOR SHORE
/KIWD THROUGH PORCUPINE MOUNTAINS AND ALONG SHORE AT ONTONAGON UP
INTO KEWEENAW/.

AT THE SAME TIME...LOW-LEVEL FLOW IS MORE CYCLONIC AND FM THE NNE
OVR NCNTRL CWA FOR MUCH OF THE NIGHT LEADING TO BETTER CHANCE OF
SEEING MODERATE SNOW AMOUNTS. FCST SOUNDINGS SHOW MOISTURE THROUGH H8
/7KFT/ THROUGH ABOUT 09Z THEN MOISTURE SETTLES BLO H85/5KFT TOWARD
DAYBREAK TUESDAY. OVER-WATER INSTABILITY IS SUFFICIENT FOR MODERATE
LAKE EFFECT AS LAKE INDUCED EQL RISE UP OVR 5KFT WITH SFC-H85 DELTA
T/S NEARING 20C. LK EFFECT SNOW PARAMETER PICKS UP ON THIS AND
DEEPER MOISTURE/UNIDIRECTIONAL LOW-LEVEL WINDS WITH POCKET OF HIGHER
VALUES BTWN 03Z AND 09Z TONIGHT. LOCAL LK EFFECT GUIDANCE SUGGESTS
12 HR SNOW AMOUNTS UP TO 6 INCHES IN THIS SETUP. UNDERCUT THIS
SLIGHTLY SINCE IDEAL LK EFFECT CONDITIONS WILL PROBABLY
ONLY BE REALIZED FOR 6-9 HRS DUE TO MARGINAL COLD AIR INITIALLY
TONIGHT AND DEEPER MOISTURE PULLING AWAY IN THE 09Z-12Z PERIOD.
THESE NEGATIVES MAY BE OFFSET BY HIGHER SLR/S AND FLUFFY NATURE OF
THE SNOW SINCE MAJORITY OF MOIST CONVECTIVE LAYER IS IN THE HEART OF
THE DGZ. SNOW RATIOS FM NAM COBB OUTPUT ARE IN THE 20-25:1.

EVEN AS DEEPER MOISTURE LEAVES FIRST THING TUESDAY MORNING...EXPECT
COVERAGE OF SNOW SHOWERS TO REMAIN HIGH THROUGH MOST OF TUESDAY
MORNING THOUGH INTENSITY SHOULD BE KNOCKED DOWN LARGELY DUE TO
INVERSIONS FALLING BLO 4KFT. OVERALL...TOTAL SNOW ACCUMS FM THIS
EVENING THROUGH EARLY TUESDAY AFTN COULD NEAR 6 INCHES IN SPOTS OVR
HIGHER TERRAIN FM HURON MOUNTAINS TO ISHPEMING/NEGAUNEE AND SKANDIA
AREAS AND INTO WESTERN ALGER COUNTY FM DEERTON TO CHATHAM. 12 HR
SNOW AMOUNTS ARE ONLY MARGINALLY SUFFICIENT FOR ADVY THOUGH AND
SINCE THERE IS NOT MUCH FOR ADDITIONAL HAZARDS /CONSIDERABLE BLSN
FOR EXAMPLE/ HAVE HELD OFF ON ISSUING ADVY ATTM. WILL LET DAYSHIFT
TAKE ONE MORE LOOK AT DETAILS AND PUT HEADLINE UP IF NEEDED. NORTH
WINDS BACK MORE NORTHWEST BY LATE TUESDAY AFTN...SHIFTING
DIMINISHING SNOW SHOWERS ACROSS MUCH OF ALGER COUNTY. AWAY FM
LK EFFECT TUESDAY...MAIN ISSUE WILL BE RETURN TO WINTER WITH
TEMPERATURES IN THE TEENS/20S AND WIND CHILL READINGS IN THE
SINGLE DIGITS ABOVE ZERO FOR MUCH OF THE DAY. BASICALLY THAT IS
FAIRLY TYPICAL FOR THIS TIME OF YEAR...BUT GIVEN THE RECENT WARMTH
IT WILL DEFINITELY FEEL ON THE CHILLY SIDE.

.LONG TERM /TUE NIGHT THRU SUN/...

TUE NIGHT...SHRTWV RDG/SFC HI PRES WL DOMINATE. WITH MOCLR SKIES...
LGT WINDS...AND PWAT AS LO AS 0.10-0.15 INCH OR 40-50 PCT OF
NORMAL...EXPECT TEMPS OVER THE INTERIOR SRN TIER TO DIP AOB THE LO
END OF GUIDANCE. AS THE SFC RDG SINKS SLOWLY TO THE S THRU THE
NGT...A STRONGER W WIND WITH H925 WINDS UP TO 30 KTS WL INFLUENCE
AREAS NEAR LK SUP AND LIMIT THE DIURNAL TEMP FALL THERE.

WED...CWA WL BE UNDER STRENGTHENING WLY FLOW/H925 WINDS UP TO 35 KTS
BTWN HI PRES RDG SINKING TOWARD THE OH RIVER VALLEY AND ANOTHER LO
PRES/ATTENDANT COLD FNT TRACKING ACRS NRN ONTARIO ASSOCIATED WITH
SHRTWV WITHIN DEEPENING UPR TROF OVER HUDSON BAY. WITH DRY
AIRMASS/PWAT ARND 0.15 INCH LINGERING...EXPECT A MOSUNNY DAY. H85
TEMPS ARE PROGGED TO REBOUND TO ARND -5C...SO THE DAY WL BE WARMER.
BUT GUSTY W WIND WL MAKE THE AIR FEEL COLDER DESPITE SLOWLY INCRSG
SOLAR ANGLE.

WED NIGHT...COLD FNT ASSOCIATED WITH DEEPENING UPR TROF CENTERED
NEAR HUDSON BAY IS FCST TO DROP INTO NRN LK SUP BY 12Z THU. LACK OF
ANY MSTR INFLOW/DRY NATURE OF ANTECEDENT AIRMASS ARGUES FOR A DRY
FCST WITH LTL IN THE WAY OF PRE-FRONTAL CLD COVER AS WELL...BUT DID
INTRODUCE SOME SCHC POPS OVER THE N HALF OF LK SUP OVERNGT TO MARK
ARRIVAL OF THIS FNT. ALTHOUGH PWAT IS FCST TO REMAIN LO ARND 0.15
INCH...STEADY W WIND WL LIMIT THE DIURNAL FALL OF TEMP.

EXTENDED...MODELS NOW IN GOOD AGREEMENT FOR THU SHOWING A SHARP COLD
FROPA WITH ONLY A WEAK SFC LO RUNNING ALONG THIS BNDRY...IN CONTRAST
TO SOME PAST MODEL RUNS THAT DEPICTED A DEEPER LO. WITH DRY AIRMASS
PRECEDING THE FROPA...WENT NO HIER THAN CHC POPS EVEN NEAR LK SUP.
INFUSION OF MUCH COLDER AIR BEHIND THIS FROPA WITH 00Z GFS SHOWING
H85 TEMPS FALLING AS LO AS -25C AND INVRN BASE ARND 5K FT WL RESULT
IN SOME LES...MOST PREVALENT IN AREAS FAVORED BY FCST NNW FLOW THRU
FRI. TENDED TO GO HIER THAN MODEL CONSENSUS POPS IN THESE FAVORED
AREAS GIVEN TENDENCY FOR MODELS TO UNDERDO LES. THEN AS ARCTIC HI
PRES DRIFTS SEWD TOWARD THE UPR MIDWEST ON SAT...BACKING FLOW TO
MORE W WL SHIFT THE LES INTO AREAS FAVORED BY THAT FLOW. LINGERING
LES SHOULD DIMINISH/END ON SUN AS UPR TROF LIFTS OUT/FLOW TURNS MORE
ACYC WITH HI PRES DRIFTING INTO THE OH RIVER VALLEY. NEAR NORMAL
TEMPS ON THU WL SINK AOB NORMAL THU NGT THRU SAT AS ARCTIC AIRMASS
INVADES THE UPR LKS. TEMPS WL REBOUND ON SUN WITH BLDG UPR RDG INTO
THE GRT LKS/RETURN LLVL SW FLOW OF WARMER AIR TO THE N OF SFC HI IN
THE OH VALLEY.
&&

.AVIATION /FOR THE 06Z TAF ISSUANCE/...

VFR CONDITIONS SHOULD PREVAIL THE REST OF TONIGHT AT ALL TAF SITES.
TIGHTER PRES GRADIENT BTWN HIGH PRES SINKING S THRU THE PLAINS AND A
COLD FRONT DROPPING S INTO NRN ONTARIO WILL RESULT IN LLWS OVERNIGHT
AT KIWD AND KSAW. FAVORABLE WRLY FLOW WILL KEEP WINDS GUSTY AT
KCMX...SO LLWS IS LESS LIKELY THERE. THE COLD FRONT WILL PASS THRU
THE TAF SITES MON MORNING...BRINGING MVFR CLOUD DECK AND PROBABLY
SOME FLURRIES OR -SHSN INTO MON EVENING.
&&

.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...

EXPECT W WINDS UP TO 30 KTS EARLY TODAY TO WEAKEN A BIT WITH THE
APPROACH OF A COLD FRONT BUT THEN VEER TO THE N BY THIS EVNG AND
CRANK BACK UP TO 30 KTS FOLLOWING A COLD FRONTAL PASSAGE. THERE MAY
BE SOME GALE FORCE GUSTS TO 35 KTS AS WELL SINCE THE ARRIVAL OF MUCH
COLDER AIR OVER THE RELATIVELY WARM LAKE WATERS ENHANCES MIXING.
HOISTED A HEAVY FREEZING SPRAY WARNING FOR MUCH OF CENTRAL LAKE SUP
WITH INVASION OF ARCTIC AIR/HIER WAVES FORECAST IN THIS AREA INTO
TUE MORNING. THESE AUSTERE CONDITIONS WILL IMPROVE ON TUE WITH THE
ARRIVAL OF A HI PRES RIDGE/LIGHTER WINDS IN THE AFTERNOON. LIGHT
WINDS ON TUE EVENING ASSOCIATED WITH THE PASSING SFC HI PRES RIDGE
WILL INCREASE UP TO 30 KTS BY WED MORNING AS PRES GRADIENT SHARPENS
ONCE THE HI SINKS TOWARD THE OH RIVER VALLEY. THERE MAY BE A FEW
GALE FORCE GUSTS TO 35 KTS OVER THE E WITH LONGER FETCH OF CHILLY
AIR OVER THE RELATIVELY WARM LAKE WATERS ALLOWING FOR MORE MIXING.
ALTHOUGH WINDS MAY DIMINISH LATE WED NIGHT INTO THU FOR A TIME AS
ONLY A WEAK LO PRES CENTER MOVES JUST TO THE NE OF THE LAKE...
EXPECT A STRONGER NNW FLOW TO 30 KTS TO DEVELOP FOLLOWING A COLD
FRONTAL PASSAGE ON THU. THE COMBINATION OF THESE STRONG WINDS AND
THE ARRIVAL OF VERY COLD AIR MAY RESULT IN HEAVY FREEZING SPRAY OVER
PORTIONS OF THE LAKE THRU THU NIGHT. THE CLOSER APPROACH OF A HI
PRES RIDGE WILL BRING DIMINISHING WINDS BY FRI.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
  HEAVY FREEZING SPRAY WARNING FROM 10 PM EST /9 PM CST/ THIS
     EVENING TO 10 AM EST /9 AM CST/ TUESDAY FOR LSZ241>244-263-
     264.

LAKE MICHIGAN...
NONE.
&&

$$

SYNOPSIS...JLA
SHORT TERM...JLA
LONG TERM...KC
AVIATION...VOSS
MARINE...KC







AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

 404 AM EST MON FEB 6 2012

LATEST UPDATE...ALL SECTIONS EXCEPT AVIATION...

.SYNOPSIS...(404 AM EST MON FEB 6 2012)
A COLD FRONT WILL CROSS THE REGION TONIGHT.  THIS SYSTEM WILL BRING
VERY LITTLE SNOW...HOWEVER IT WILL RETURN TEMPERATURES TO NEAR
NORMAL VALUES FOR MID WEEK.  ANOTHER SURGE OF COLDER AIR ARRIVES BY
FRIDAY AND INTO THE WEEKEND.  SOME LAKE EFFECT SNOW SHOWERS WILL BE
SEEN ALONG WITH THIS COLDER AIR.

&&

.SHORT TERM...(404 AM EST MON FEB 6 2012)
(TODAY THROUGH WEDNESDAY)
THE SKY FORECAST REMAINS THE BIGGEST CHALLENGE TODAY AND THE
RESULTANT AFFECTS ON THE REGION/S TEMPS.  A LARGE AREA OF STRATUS
COVERED MUCH OF WISCONSIN THIS MORNING AND IT WAS PRESSING EASTWARD
AT A 5-10 MPH PACE.  THAT SPEED ALONG WOULD SUGGEST THAT THE CLOUD
DECK WOULD NOT REACH THE MICHIGAN SHORE UNTIL MID AFTERNOON.
HOWEVER THERE WAS ALSO RANDOM PATCHES OF STRATUS ACROSS LOWER
MICHIGAN TOO.  THE RUC LOW LEVEL MOISTURE PROGS SUGGEST A RAPID
EXPANSION OF THE STRATUS SO THAT THE ENTIRE GRR CWA IS COVERED BY
CLOUDS BY 12Z.  THIS LOOKS UNREASONABLE TO ME.  HOWEVER BELIEVE THE
STRATUS WILL LIKELY SPEED UP IT/S EASTWARD TRACK AS IT MOVES ACROSS
THE LAKE THIS MORNING.  ALSO...THE RANDOM PATCHES MAY ALSO EXPAND
SOMEWHAT THIS MORNING.  BUT THEN THE ISSUE BECOMES...WHAT WILL THE
INCREASED MIXING DO TO THE STRATUS.  I SENSE THAT IT WILL HELP IT TO
ERODE SUCH THAT MUCH OF THE STRATUS BECOMES LESS OF A FACTOR BY MID
DAY.  SO I WILL PLAY THE FORECAST SUCH THAT SOME STRATUS WILL LINGER
THROUGH THE MORNING...BUT WILL BANK ON A MOSTLY SUNNY AFTERNOON AS
THE EASTWARD EDGE OF THE STRATUS MIXES OUT.  IF THIS INDEED OCCURS
TEMPS WILL REACH WELL INTO THE 40S AGAIN TODAY...IF IT DOES NOT
OCCUR TEMPS MAY HOLD FROM 35 TO 40.

THE ARCTIC FRONT IS STILL ON SCHEDULE FOR TONIGHT.  THE LACK OF DEEP
MOISTURE WILL RESULT IN NO SNOW OR PERHAPS A RANDOM FLURRY.  THE LOW
LEVEL FLOW BEHIND THE FRONT SHOULD BE 030-040...KEEPING ANY LAKE
EFFECT ON THE OTHER SIDE OF THE LAKE.  WE WILL HAVE TO KEEP AN EYE
ON POSSIBLE SNOW SHOWERS OFF OF SAGINAW BAY WHICH MAY MOVE INTO
AREAS AROUND ST. JOHNS BY TUESDAY.

HAVE LOW POPS IN FOR TUE AFTERNOON INTO TUESDAY NIGHT FOR AREAS
SOUTH OF I-96.   A SHORT WAVE COMES ACROSS THE LOWER GREAT LAKES AND
COMBINED WITH THE EXITING ARCTIC FRONT MAY PRODUCE SOME LIGHT SNOW.
LOW LEVEL WINDS SHOULD ALSO BACK TO THE NW BY LATE TUESDAY NIGHT
WHICH COULD BRING A FEW SNOW SHOWERS OFF THE LAKE.  BY WEDNESDAY THE
MOISTURE PROFILE BECOMES VERY SHALLOW AS RIDGING BUILDS INTO THE
AREA. EXPECT SUNSHINE WITH NEAR NORMAL TEMPS.

&&

.LONG TERM...(404 AM EST MON FEB 6 2012)
(WEDNESDAY NIGHT THROUGH SUNDAY)
A CLIPPER MOVES ACROSS NORTHERN LOWER MICHIGAN THURSDAY NIGHT
SWINGING AN ARCTIC FRONT SOUTH ACROSS THE FORECAST AREA.

LOOKS LIKE SOME SNOW WILL ACCOMPANY THE FROPA WITH STRONG SFC
CONVERGENCE. LAKE EFFECT BEHIND THE FRONT WILL CONTINUE INTO
SATURDAY BUT FLOW GOES NORTH AND THEN EVENTUALLY NORTHEAST WHICH
WOULD PUSH THE SNOW SHOWERS OFFSHORE. THIS COMBINED WITH INVERSION
HEIGHTS BELOW 10 KFT SHOULD LIMIT ACCUMS...WITH MOST OF THE SNOW
CONCENTRATED FAIRLY CLOSE TO THE LAKE MICHIGAN SHORE.

&&

.AVIATION...(1156 PM EST SUN FEB 5 2012)
MVFR CLOUDS WERE ON THE INCREASE FROM KMKG TO KRQB.  THIS BAND WAS
SHIFTING SOUTHEAST AND WILL LIKELY IMPACT THE TAF SITES FOR A FEW
HOURS TONIGHT.  TOWARD DAYBREAK THE MORE SIGNIFICANT AREA OF IFR OR
LOWER CLOUDS IN WI...WILL BE ARRIVING IN KMKG.  THEY WILL CONTINUE
EAST AND SOME UNCERTAINTY EXISTS AS TO HOW FAR EAST THEY WILL GO.  I
DID LOWER ALL BUT KLAN AND KJXN DOWN TO IFR FOR MON AM INTO THE
EARLY AFTERNOON HOURS.  SOME INDICATIONS THE MOISTURE WILL TRY TO
THIN OUT DURING THE AFTERNOON.  A THICKER BAND OF CLOUDS AND PERHAPS
FZDZ WILL ARRIVE OF MON NIGHT. I DID NOT INCLUDE THE FZDZ WITH THIS
FORECAST...BUT THERE IS AT LEAST A LOW RISK AT THIS POINT.

&&

.MARINE...(404 AM EST MON FEB 6 2012)
SCA IN AFFECT FOR TODAY WITH WSW WINDS TO AROUND 20 KTS.  LOOKS LIKE
WE WILL SEE A BRIEF BREAK IN THE HIGHER WINDS AND WAVES EARLY
TONIGHT AS A COLD FRONT COMES THROUGH.  BUT THEN BEHIND THE FRONT
WAVES SHOULD INCREASE AGAIN LATE TONIGHT OR EARLY TUESDAY IN THE
COLD ADVECTION PATTERN.

&&

.HYDROLOGY...(404 AM EST MON FEB 6 2012)
MINIMAL HYDRO CONCERNS GIVEN THE LACK OF PCPN.  ALSO THE SNOW PACK
TO THE NORTH WILL END IT/S MELTING BY TONIGHT AS THE COLD FRONT
COOLS REGIONAL TEMPS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY ST. JOE TO MANISTEE THROUGH TODAY.

&&

$$

SYNOPSIS:     JK
SHORT TERM:   JK
LONG TERM:    OSTUNO
AVIATION:     MJS
MARINE:       JK
HYDROLOGY:    JK











AREA FORECAST DISCUSSION

NWS GAYLORD MI

 347 AM EST MON FEB 6 2012

.SYNOPSIS.../ISSUED AT 347 AM/

HIGH PRESSURE ACROSS THE REGION THROUGH MIDDAY WILL GIVE WAY TO AN
APPROACHING COLD FRONT BY EVENING. THE PASSAGE OF THIS FRONT WILL
USHER IN A BRIEF SHOT OF MUCH COLDER WEATHER FOR THE DAY ON
TUESDAY...ALONG WITH CHANCES FOR SOME LIGHT SNOW SHOWERS.
TEMPERATURES WILL WARM BACK ABOVE NORMAL BY THURSDAY AS HIGH
PRESSURE AGAIN ARRIVES...BEFORE ANOTHER PUSH OF COLD WEATHER AND
LAKE SNOW SHOWERS ARRIVES FOR FRIDAY INTO THE WEEKEND.

DL

&&

.SHORT TERM.../ISSUED AT 347 AM/...TODAY

A SHARP COLD FRONT IS MOVING SOUTH TOWARD THE NORTH SHORE OF
SUPERIOR EARLY THIS MORNING. THERE IS NO PRECIP...AND IN FACT NO
CLOUDS...WITH THE FRONT ITSELF...THOUGH LOW CLOUDS ARE EXTENSIVE
BEHIND IT. IN THE WARM SECTOR...A FEW PATCHES OF LOW CLOUDS REMAIN
OVER MI AND ENVIRONS...WITH MORE WIDESPREAD CLOUD COVER IN THE UPPER
MS VALLEY AND EXPANDING ESE-WARD. CLOUD/TEMP TRENDS ARE AGAIN
THE MAIN CONCERN TODAY.

COLD FRONT WILL REACH EASTERN UPPER MI TOWARD 18Z...AND WILL BE
NEARING SAGINAW BAY AT 00Z. OUTSIDE OF VERY SHALLOW SURFACE-BASED
MOISTURE...THE DEEP AIRMASS IN THE WARM SECTOR REMAINS VERY DRY
(850-700MB RH LESS THAN 30 PERCENT...PWATS 0.25-0.30). THERE IS NO
RISK OF PRECIP AHEAD OF...OR WITH...THE FRONT. HOWEVER...CLOUD
TRENDS IN THE WARM SECTOR REMAIN PROBLEMATIC. THE AIRMASS BELOW
925MB REMAINS MOIST (SURFACE DEW POINTS REFLECT THIS). LARGER LOW
CLOUD MASS TO OUR WEST IS TRYING TO WORK EAST THIS MORNING...BEFORE
MIXING CAN EAT AWAY AT IT TOO MUCH. DOWNSLOPING WINDS INTO FAR
EASTERN WI ARE KEEPING THE CLOUD MASS FROM ADVANCING AS FAR EAST AS
IT COULD. MODEL GUIDANCE IS ALL OVER THE MAP...FROM THE NAM NOT
ALLOWING ANY LOW CLOUDS TO CROSS THE LAKE...TO THE HRRR WHICH
COMPLETELY SOCKS IN ALL OF NORTHERN MI BY 16Z.

GIVEN SATELLITE TRENDS OF AN CLOUD MASS CLEARLY STRUGGLING TO MOVE
EAST...WILL NOT BRING IN OVERCAST SKIES THIS MORNING. WE/RE STILL
PLENTY MOIST DOWN LOW...AND SMALL PATCHES OF LOW CLOUDS COULD FORM
JUST ABOUT ANYWHERE THIS MORNING. WE MAY ALSO BE NEED MOIST ENOUGH
TO QUICKLY FIRE A SHALLOW CU DECK BEFORE MIXING IT OUT TOWARD
MIDDAY.

BEHIND THE FRONT...LOW CLOUDS WILL BECOME EXTENSIVE FROM NORTH TO
SOUTH DURING THE AFTERNOON. THERE MAY BE AN OUTSIDE SHOT AT A BIT OF
DRIZZLE OR SOME FLURRIES IN CENTRAL/WESTERN CHIPPEWA CO VERY LATE.
INVERSION-TOP (875MB) TEMPS REACH -7/8C (SO DELTA T/S INTO THE LOWER
TEENS).

MAX TEMPS WILL AGAIN BE QUITE MILD. WILL FAVOR WARMER GUIDANCE
NUMBERS GIVEN A BALMY START TO THE DAY. MAX TEMPS MID/UPPER 30S
NORTH TO MID 40S FAR SE.

JZ

&&

.LONG TERM.../ISSUED AT 347 AM/...TONIGHT AND BEYOND

THE UPPER TROF FORCING TODAY/S COLD FRONT WON/T ACTUALLY MAKE IT TO
OUR NEIGHBORHOOD UNTIL LATE TUESDAY. LOW LEVEL COLD ADVECTION WILL
CONTINUE UNTIL THEN (THOUGH THE AIRMASS SHOULD MODERATE WITH SOME
SUNSHINE TUESDAY). DESPITE REASONABLE INSTABILITY...THE POOR NORTH
FETCH...LACK OF MOISTURE...AND ARRIVAL OF SURFACE RIDGING/
ANTICYCLONIC CURVATURE WILL LIMIT LAKE EFFECT SNOW (LES) POTENTIAL.
AS HIGH PRESSURE PRESSES SOUTH INTO THE CENTRAL PLAINS BY
WEDNESDAY...WESTERLY LOW LEVEL FLOW AND WARM ADVECTION WILL AGAIN BE
RE-ESTABLISHED HERE. THAT WILL BE BRIEF...AS A STRONGER SHOT OF COLD
AIR APPEARS LIKELY AT THE END OF THE WORK WEEK. TEMP/PRECIP
TRENDS...MAINLY ASSOCIATED WITH THE COLD AIR TONIGHT/TUESDAY AND
AGAIN AT THE END OF THE WEEK...ARE THE MAIN CONCERNS.

TONIGHT...COLD FRONT WILL MOVE SOUTH OF MI...WHILE 500MB TROF WILL
ADVANCE TO NORTHERN SUPERIOR. SURFACE HIGH PRESSURE WILL MOVE INTO
ND...WITH RIDGING EXTENDING JUST NORTH OF SUPERIOR. 1000-850MB WINDS
WILL BECOME N/NNW BY 03Z...AND N/NNE BY 12Z. WE DO MANAGE TO GET
850-700MB RH LEVELS UP TO 60 PERCENT OR SO...IN THE EVENING AROUND
EASTERN UPPER...EXPANDING SOUTH OVERNIGHT (DRYING OUT ON EASTERN
SUPERIOR TOWARD 12Z). DELTA T/S REACH IN THE MID TEENS IN THE
OVERNIGHT HOURS...WHICH SHOULD SPOT OUT A FEW SNOW SHOWERS IN FAR
WESTERN AND FAR EASTERN SECTIONS OF THE FORECAST AREA (GIVEN
UNFAVORABLE N FETCH). WILL KEEP POPS QUITE SMALL...NAM/LOCAL WRF IN
EXCELLENT AGREEMENT IN GENERATING NO QPF ANYWHERE IN THE FORECAST
AREA TONIGHT. MEANWHILE...THE I-75/US-127 CORRIDOR IN NORTHERN
LOWER...AND FAR EASTERN UPPER...SHOULD CLEAR PARTIAL CLEARING. MIN
TEMPS WILL RANGE FROM MID/UPPER SINGLE DIGITS IN FAR EASTERN
UPPER...TO LOWER 20S IN SOME SOUTHERN SECTIONS.

TUESDAY...THE MAIN FACTOR IS THE STRONG SURFACE RIDGE THAT CROSSES
SUPERIOR AND SETTLES ACROSS UPPER/FAR NORTHERN LOWER MI BY 00Z.
ASSOCIATED DRYING (850-700MB RH GO BELOW 25 PERCENT) AND
ANTICYCLONICALLY CURVED FLOW WILL COMPLETELY PUT THE KIBOSH ON LES
AS THE DAY PROCEEDS...DESPITE CONTINUED PRESENCE OF CHILLY AIR
(DELTA T/S MID TEENS). EXPECT CLOUD COVER TO ERODE AS WELL AS WE
MOVE THRU THE AFTERNOON. WILL CONTINUE WITH A SMALL CHANCE OF -SHSN
IN THE MORNING ALONG WESTERN AND EASTERN FRINGES OF THE FORECAST
AREA...AND GO DRY IN THE AFTERNOON. MAX TEMPS UPPER TEENS TO MID 20S.

TUE NIGHT THRU WED NIGHT...SURFACE RIDGE AXIS WILL CONTINUE TO MOVE
SOUTH ACROSS LOWER MI TUESDAY NIGHT...AND WILL EVENTUALLY REACH THE
OHIO VALLEY BY THURSDAY MORNING. BY THEN...THE NEXT COLD FRONT WILL
BE REACHING SUPERIOR. IN BETWEEN...WESTERLY 1000-850MB WINDS WILL
KICK THE COLD AIR OUT FOR A BIT...WITH 850MB TEMPS REACHING -6C BY
WEDNESDAY EVENING. THIS AIRMASS WILL REMAIN QUITE DRY IN THE MID AND
UPPER LEVELS...THOUGH WE MAY AGAIN BE CONTENDING WITH OCCASIONAL LOW
CLOUD ISSUES (ESPECIALLY WEDNESDAY NIGHT) LIKE WE/VE SEEN THE LAST
SEVERAL DAYS. STILL...PARTLY CLOUDY TO MOSTLY CLEAR WILL COVER MUCH
OF THESE PERIODS...WITH NO RISK FOR PRECIP. MIN TEMPS WILL BE QUITE
CHILLY TUE NIGHT...SINGLE DIGITS TO MID TEENS. MAX TEMPS WEDNESDAY
MID 20S TO LOWER 30S. MIN TEMPS WED NIGHT MID TEENS TO LOWER 20S.

JZ

LATER PERIODS (THURSDAY THROUGH SUNDAY)...BRIEF PATTERN CHANGE STILL
ANTICIPATED HEADING INTO THE WEEKEND...AS STRONG MERIDIONAL RIDGING
BUILDING UP THE WEST COAST OF NORTH AMERICA BRIEFLY DISLODGES THE
POLAR VORTEX TOWARD HUDSON BAY. HOWEVER...AS MENTIONED IN THIS SPACE
SEVERAL TIMES THE PAST FEW DAYS...THE PATTERN CHANGE STILL LOOKS TO
BE VERY BRIEF...WITH THE COLDEST AIR RELEGATED TO FRIDAY AND
SATURDAY DAY WHEN H8 TEMPS ARE STILL PROGGED BY MAJORITY OF 00Z
GUIDANCE TO DIP TO AROUND -21C OR SO AT THEIR COLDEST. OVERALL
HEMISPHERIC PATTERN DURING THE WEEKEND TIMEFRAME IS RATHER
UNSTABLE...FEATURING A WAVERING 3-4 WAVE PATTERN...AND THUS NO REAL
SURPRISE TO SEE GUIDANCE CONTINUING EARLIER TRENDS OF ERASING THE
BRIEF PATTERN SHIFT AS STRONG PACIFIC JET ENERGY AGAIN PLOWS THROUGH
MUCH OF THE CONUS. THIS SHOULD RAPIDLY SHIFT THE CORE OF COLDEST AIR
TO THE EAST BY SUNDAY...WITH THE STRONG POSSIBILITY FOR ANOTHER
ROUND OF QUITE WARM WEATHER (BY FEBRUARY STANDARDS AT LEAST) TO
ARRIVE INTO THE FOLLOWING WEEK...THOUGH THAT`S GETTING A BIT AHEAD
OF THINGS FOR THIS FCST.

LOOKING AT THE SPECIFICS...STILL LOOKS LIKE A PERIOD OF SOME LAKE
EFFECT SNOW SHOWERS (BASICALLY A GIVEN) AS COLDER AIR POURS INTO THE
AREA LATER THURSDAY THROUGH SATURDAY...WITH TRENDS THE PAST FEW DAYS
STILL SUGGESTING A MEAN NORTHERLY COMPONENT TO THE LOW LEVEL FLOW.
THAT SAID...MESOSCALE PROCESSES MAY INCREASINGLY COME INTO PLAY BY
SATURDAY AS LOW LEVEL FLOW BECOMES INCREASINGLY ANTICYCLONIC BUT
OVERLAKE INSTABILITY REMAINS STELLAR. WHILE OVERALL MOISTURE
PROFILES DURING THE FRIDAY/SATURDAY TIMEFRAME ARE NOTHING REALLY
IMPRESSIVE...DEPTH OF THE DGZ THROUGH THE LAKE-INDUCED CLOUD LAYER
DOES ARGUE THAT SOME LOCALIZED MODEST FLUFFY ACCUMULATIONS WILL BE
POSSIBLE...MAINLY DOWNWIND OF GRAND TRAVERSE BAY AND PERHAPS INTO
FAR NORTHWESTERN CHIPPEWA COUNTY. SNOW SHOWER CHANCES WILL DWINDLE
QUICKLY HEADING THROUGH THE DAY ON SUNDAY AS LOW LEVEL INSTABILITY
WANES...WITH AN OVERWHELMING MAJORITY OF GUIDANCE SIGNALS SUGGESTING
H8 TEMPS MODIFY INTO THE SINGLE DIGITS BELOW ZERO BY 00Z MONDAY.
TEMPS THROUGH THE EXTENDED WILL FINALLY BE A BIT BELOW NORMAL FOR
ONCE.

LAWRENCE

&&

.MARINE.../ISSUED AT 347 AM/

SOMEWHAT BLUSTERY WEST WINDS WILL CONTINUE UNTIL A COLD FRONT...NOW
NEARING SUPERIOR...CROSSES NORTHERN MI THIS AFTERNOON AND EARLY
EVENING. SMALL CRAFT ADVISORIES ALREADY UP FOR ALL WATERS...AND WILL
REMAIN UNCHANGED. COLD NORTH WINDS MAY SUPPORT ADVISORIES INTO
TONIGHT (ESPECIALLY AS INSTABILITY INCREASES)...BUT WILL HOLD OFF ON
ANY EXTENSIONS AT THIS TIME.

JZ

&&

.AVIATION.../ISSUED AT 1150 PM/...VALID FOR 06Z TAFS

A MAINLY SCATTERED DECK OF MVFR SC ACROSS NW LWR MICHIGAN
(PLN/TVC/MBL) WILL TEMPORARILY BECOME BKN VERY LATE TONIGHT/EARLY
MONDAY MORNING AS THE ERN EDGE OF A PERSISTENT LOW STRATUS DECK OVER
WISCONSIN TRIES TO PUSH INTO LWR MICHIGAN. DAYTIME MIXING SHOULD
ERODE THE ERN EDGE OF THE STRATUS DECK...WITH VFR CONDITIONS
RETURNING TO NW LWR MICHIGAN BY AROUND LATE MORNING. ADDITIONAL LOW
CLOUDS WILL DROP SOUTH OUT OF ONTARIO INTO NRN MICHIGAN DURING LATE
AFTERNOON/EARLY EVENING ALONG AND BEHIND A COLD FRONT. LLWS IS
EXPECTED AT ALL TAF SITES UNTIL AROUND MID MORNING.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR
     LHZ345>349.
LM...SMALL CRAFT ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR
     LMZ323-341-342-344>346.
LS...NONE.

&&

$$







AREA FORECAST DISCUSSION

NWS GRAND RAPIDS MI

 1155 PM EST SUN FEB 5 2012

LATEST UPDATE...AVIATION...

.SYNOPSIS...(400 PM EST SUN FEB 5 2012)
FAIRLY QUIET WEATHER CONDITIONS WILL CONTINUE INTO EARLY THIS
WEEK...WITH A WARMER THAN NORMAL DAY EXPECTED MONDAY. AFTER SOME
MORNING CLOUDS...WE SHOULD SEE SUNSHINE THAT WILL BOOST TEMPERATURES
WELL INTO THE 40S. A COLD FRONT WILL SLIP SOUTH THROUGH THE STATE
MONDAY NIGHT WHICH WILL FILTER COLDER AIR IN FOR MID WEEK. LITTLE IN
THE WAY OF PRECIPITATION IS EXPECTED THROUGH THURSDAY. EVEN COLDER
AIR MOVES IN FOR LATE IN THE WEEK WITH SOME LAKE EFFECT SNOW SHOWERS
AS WELL. HIGHS WILL BE BACK DOWN IN THE 30S FOR MID WEEK AND IN THE
20S BY FRIDAY.

&&

.SHORT TERM...(400 PM EST SUN FEB 5 2012)
(TONIGHT THROUGH TUESDAY NIGHT)
CLOUDS HAVE BEEN THE FOCUS OF THE SHORT TERM FOR DAYS AND TODAY IS
NO EXCEPTION. A BATCH OF STRATUS IS LOCATED OVER LAKE MICHIGAN THIS
AFTERNOON...AND FEEL IT...ALONG WITH CLOUDS/MOISTURE UPSTREAM WILL
ADVECT INTO THE FORECAST AREA FROM THE WEST. ESSENTIALLY ENVISION A
GRADUAL EXPANSION TO THE EAST OF THE CLOUDS OVER THE LAKE AND POINTS
FURTHER WEST. RUC HAS SOMEWHAT OF A HANDLE ON THIS AND SEE NO REASON
TO ARGUE AT THIS POINT. THE STRATUS LATELY HAS BEEN PROBLEMATIC
THOUGH AND CONFIDENCE IS NOT HIGH IN ITS EVOLUTION. LOOKING FOR
MORNING CLOUDS TO LIFT WITH A FAIR AMOUNT OF SUNSHINE ON MONDAY.
HIGH SHOULD BE WELL ABOVE NORMAL IN THE 40S.

A COLD FRONT WILL DROP SOUTH THROUGH THE AREA MONDAY NIGHT. MOISTURE
DEPTH IS EXTREMELY SHALLOW...SO EXPECTING IT TO COME THROUGH FOR THE
MOST PART DRY. DO HAVE A FEW SNOW SHOWERS IN NORTHERLY FLOW ACROSS
THE NORTHWEST CORNER OF THE FORECAST AREA MONDAY NIGHT/TUESDAY
MORNING AS DELTA T/S CREEP ABOVE 13 DEGREES C. BY TUESDAY AFTERNOON
THOUGH THE FLOW IS TRENDING NORTHEAST/OFF SHORE. LOWER TROP DRIES
OUT FROM THE NORTH TUESDAY NIGHT DESPITE LAKE INSTABILITY. OVERALL
DRY CONDITIONS TUESDAY NIGHT WITH DECREASING CLOUDS.

&&

.LONG TERM...(400 PM EST SUN FEB 5 2012)
(WEDNESDAY THROUGH SUNDAY)
MAIN FOCUS OF THE FCST IN THE LONG TERM IS ON THE LAKE EFFECT
POTENTIAL FOR THE END OF THE WORK WEEK AND THE FIRST PORTION OF NEXT
WEEKEND.

IT APPEARS THAT WE SHOULD END UP IN BETWEEN SYSTEMS AT THE BEGINNING
OF THE LONG TERM ON WED. THERE WILL BE A SHORT WAVE MISSING THE AREA
TO THE SOUTH AND THERE WILL BE A WAVE THAT WILL BE GETTING READY TO
DROP SE ON THE SRN PERIPHERY OF THE POLAR VORTEX CENTERED ACROSS
HUDSON BAY. THIS WILL PLACE THE AREA UNDER SHORT WAVE RIDGING AND
DRY AND COOLER AIR.

THE MODELS ARE INDICATING THAT STRONG SHORT WAVE ENERGY COMING FROM
NRN CANADA SHOULD BE THE CAUSE FOR A COLD FRONT MOVING INTO THE AREA
LATER ON THU FROM THE NORTH. THIS WILL BE RESPONSIBLE FOR BRINGING
IN A GLANCING BLOW OF ARCTIC AIR TO THE AREA. H850 TEMPS WILL DROP
INTO THE NEGATIVE UPPER TEENS C. UPPER CYCLONIC FLOW WILL SETTLE IN
FOR FRI AND INTO SAT...AND WILL BRING THE POTENTIAL FOR LAKE EFFECT.
LAKE EFFECT PARAMETERS DO NOT LOOK FAVORABLE FOR A BIG EVENT.
MOISTURE DOES NOT LOOK VERY FAVORABLE MOST OF THE TIME...EXCEPT
MAYBE DECENT FRI MORNING. THERE IS EVEN POTENTIAL PER THE NEW 12Z
EURO WHERE THE FLOW WOULD END UP FROM THE NE...AND WE WOULD SEE
LITTLE IF ANY LAKE EFFECT. STILL A LOT OF DETAILS TO IRON OUT.

MODELS ARE ALL IN GOOD AGREEMENT IN THE CYCLONIC FLOW LIFTING OUT BY
SUN MORNING. THIS LOOKS TO OCCUR AS THE AMPLIFIED RIDGE OVER WRN
CANADA THAT HELPS TO SEND THE ARCTIC AIR DOWN GETS FLATTENED BY A
STRONG PACIFIC JET EXPECTED TO MOVE OVER THE PACIFIC NW. THIS SHOULD
SHIFT OUR FLOW TO A MORE MILD AND ZONAL PATTERN OFF OF THE PACIFIC
LATE NEXT WEEKEND.

&&

.AVIATION...(1155 PM EST SUN FEB 5 2012)
MVFR CLOUDS WERE ON THE INCREASE FROM KMKG TO KRQB.  THIS BAND WAS
SHIFTING SOUTHEAST AND WILL LIKELY IMPACT THE TAF SITES FOR A FEW
HOURS TONIGHT.  TOWARD DAYBREAK THE MORE SIGNIFICANT AREA OF IFR OR
LOWER CLOUDS IN WI...WILL BE ARRIVING IN KMKG.  THEY WILL CONTINUE
EAST AND SOME UNCERTAINTY EXISTS AS TO HOW FAR EAST THEY WILL GO.  I
DID LOWER ALL BUT KLAN AND KJXN DOWN TO IFR FOR MON AM INTO THE
EARLY AFTERNOON HOURS.  SOME INDICATIONS THE MOISTURE WILL TRY TO
THIN OUT DURING THE AFTERNOON.  A THICKER BAND OF CLOUDS AND PERHAPS
FZDZ WILL ARRIVE OF MON NIGHT. I DID NOT INCLUDE THE FZDZ WITH THIS
FORECAST...BUT THERE IS AT LEAST A LOW RISK AT THIS POINT.

&&

.MARINE...(400 PM EST SUN FEB 5 2012)
HOISTED A SMALL CRAFT ADVISORY FROM OVERNIGHT THROUGH THE DAY ON
MONDAY. WESTERLY WINDS PICK UP TONIGHT AHEAD OF A COLD FRONT THAT
WILL BE DROPPING SOUTH INTO THE GREAT LAKES REGION ON MONDAY. ONLY
RAN THE ADVISORY THROUGH MONDAY EVENING AT THIS POINT TO SEE EXACTLY
HOW THE WINDS ARE GOING TO PLAY OUT POST FROPA. IT APPEARS THOUGH
THAT THE ADVISORY WILL NEED TO BE EXTENDED INTO MONDAY NIGHT AND
TUESDAY AS WELL AS THE WAVE FIELD...EVEN IN NORTHEAST
FLOW...PROPAGATES INTO OUR NEARSHORE WATERS.

&&

.HYDROLOGY...(400 PM EST SUN FEB 5 2012)
RIVER FLOOD ADVISORIES FOR IONIA AND BURLINGTON HAVE BEEN DROPPED IN
THE PAST 24 HOURS...WITH VICKSBURG THE ONLY ONE REMAIN. LIMITED
HYDRO CONCERNS THE NEXT FEW DAYS WILL LITTLE IN THE WAY OF
PRECIPITATION EXPECTED.

RIVER ICE WILL LIKELY BECOME MORE OF A CONCERN FROM MID WEEK INTO
NEXT WEEKEND AS WE ARE FORECAST TO COOL OFF.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY ST. JOE TO MANISTEE OVERNIGHT THROUGH
MONDAY.

&&

$$

SYNOPSIS:     DUKE
SHORT TERM:   DUKE
LONG TERM:    NJJ
AVIATION:     MJS
MARINE:       DUKE
HYDROLOGY:    DUKE












AREA FORECAST DISCUSSION...UPDATED FOR 18Z TAFS

NWS TWIN CITIES/CHANHASSEN MN

 1140 AM CST MON FEB 6 2012

.DISCUSSION...ISSUED 322 AM CST

STILL A COMPLICATED CLOUD TREND THIS MORNING. THERE DOES SEEM TO
BE A BIT STRONGER EASTWARD PUSH OF THE CLOUD EDGE WEST OF MSP PER
THE MORE WEST COMPONENT SEEN IN THE LOW LEVELS. A DIFFERENT STORY
OVER FAR SOUTHERN MN. THAT EDGE HAS A SLOW NORTHWARD DRIFT WHICH
MAY CONTINUE AND PROBABLY  KEEP SOUTH CENTRAL MN AND PARTS OF
WEST CENTRAL WI IN THE CLOUDS THOUGH THE MORNING. THE HRRR HAS HAD
THE BEST TREND ON THE LOW CLOUDS SINCE YESTERDAY...SO WILL TRY TO
FOLLOW THIS IN THE VERY SHORT TERM. THIS WILL OBVIOUSLY HAVE
IMPLICATIONS ON THE HOURLY TEMP TRENDS.

THE ARCTIC FRONT IS WELL MARKED WITH THE CLOUDS EDGE PUSHING
SOUTH OVER SOUTHERN CANADA..WILL WORK INTO OUR NORTHERN AREAS
THIS AFTERNOON. WILL USE MORE OF A MODEL DIURNAL TEMP TREND TODAY
WITH HIGHS REACHED EARLY IN THE FAR NORTHWEST ALONG WITH THE CLOUD
ISSUES IN THE SOUTH. STILL A DECENT CHANCE OF 40S FOR HIGHS IN THE
SOUTH. SOME MINOR LIFT WITH THE FRONT TONIGHT...AND THERE IS A
HINT OF PV ADVECTION LATE TONIGHT OVER FAR SOUTHERN MN FROM THE
SYSTEM TO OUR SOUTHWEST. WILL KEEP THE FLURRIES IN THE FORECAST
TONIGHT AND TUESDAY MORNING WITH THE FRONT AND WAIT ON THE
POSSIBILITY OF A SLIGHT CHANCE POP IN THE FAR SOUTH. THERE IS A
MINOR RISK OF FREEZING DRIZZLE WITH LACK OF MID LEVEL MOISTURE
UNTIL TUESDAY MORNING...BUT WITH A TIMING AN LOCATION
ISSUE...WILL WAIT ON THAT AS WELL.

A STRONGER FRONT STILL FORECAST TO AFFECT THE AREA THURSDAY AND
FRIDAY AND THE ECMWF HAS COME AROUND A LITTLE MORE IN LINE TO THE
GFS/GEM WITH THE STRENGTH. STILL A FAIR AMOUNT OF UNCERTAINTY IN
THE GFS ENSEMBLE TEMPS STARTING FRIDAY AND CONTINUING INTO THE
WEEKEND. EVEN THOUGH THE ECMWF LOOKS COLD FOR FRIDAY...IT`S TREND
FOR A GLANCING BLOW IS STILL THERE WITH A FLATTENING OF THE RIDGE
OUT WEST DURING THE WEEKEND. OUR CURRENT BLENDED FORECAST FOR
FRIDAY TEMPS MAY BE A BIT HIGH BUT THAT CAN STILL BE ADDRESSED IN
THE NEXT DAY OR TWO.

&&

.AVIATION.../18Z TAF ISSUANCE/

IFR/LIFR CIGS/VSBYS WHICH HAVE PLAGUED THE AREA FOR ABOUT THE PAST
5 DAYS HAVE NOW SHIFTED EAST OF ALL TAF SITES.  SKC CURRENTLY ACROSS
AREA...WILL HOWEVER THIS WILL BE BRIEF AS WIDESPREAD AREA OF MAINLY
MVFR CIGS CURRENTLY ADVANCING SOUTH ACROSS N MN IN WAKE OF CDFNT
PUSHES ACROSS AREA. CDFNT AT 17Z RUNS FROM AROUND STC TO NEAR MVE.
CLOUDS LAG SFC FRONT WITH LEADING EDGE FROM N OF DLH TO NEAR DTL.
MAY SEE A FEW CU/SC DEVELOP AHEAD OF MAIN BAND OF CLOUDS DURING THE
AFTERNOON.  NICE AREA OF 5MB 3 HRLY SFC PRESSURE RISES IN WAKE OF
CDFNT WILL KEEP IT ADVANCING SOUTH...AND NW WNDS SHOULD DEVELOP AT
ALL TAFS BY 21-23Z. EXPECT GUSTS AROUND 20KTS TO DEVELOP A COUPLE
HOURS AFTER FROPA WITH WINDS REMAINING GUSTY THRU MUCH OF OVERNITE.
MAY BE A FEW -SHSW MAINLY DURING THE EVENING AS CLOUDS THICKEN...
BUT VSBYS SHUD REMAIN AOA 6SM.  GOOD DRYING BEGINNING TUESDAY
MORNING AS 1040 HIGH PRESSURE BUILDS ACROS N MN.  MVFR CEILINGS
ELSEWHERE.  SOUTHWEST TO WEST WINDS AHEAD OF FRONT...BECOMING
NORTHWEST TO NORTH AND A BIT GUSTY WITH FROPA.

KMSP...NICE PRD OF SKC.  CDFNT APPROACHING MSP WITH WINDS JUST
TURNING WNW AT MGG AND HCD. TREND FROM 18Z TO 20Z WILL BE FOR SFC
WNDS TO TURN FROM AROUND 250 TO 290 AND THEN BECOMING 330.  SPEEDS
GENERALLY AOB 10 KTS UNTIL AFTER 21Z WITH GUSTS DEVELOPING 20 KTS
BY 00Z.  MAY SEE FEW015 CU DEVELOPING IN WAKE OF CDFNT WITH MVFR
CIGS MVG INTO AREA BY 01Z.  GENERALLY MVFR CIGS UNTIL AROUND
15Z-17Z...THEN CLEARING AS HIGH PRESSURE BUILDS IN.

&&

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

$$

JPR/BAP












AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

 527 AM CST MON FEB 6 2012

.UPDATED FOR 12Z AVIATION DISCUSSION BELOW...

.DISCUSSION...

STILL A COMPLICATED CLOUD TREND THIS MORNING. THERE DOES SEEM TO
BE A BIT STRONGER EASTWARD PUSH OF THE CLOUD EDGE WEST OF MSP PER
THE MORE WEST COMPONENT SEEN IN THE LOW LEVELS. A DIFFERENT STORY
OVER FAR SOUTHERN MN. THAT EDGE HAS A SLOW NORTHWARD DRIFT WHICH
MAY CONTINUE AND PROBABLY  KEEP SOUTH CENTRAL MN AND PARTS OF
WEST CENTRAL WI IN THE CLOUDS THOUGH THE MORNING. THE HRRR HAS HAD
THE BEST TREND ON THE LOW CLOUDS SINCE YESTERDAY...SO WILL TRY TO
FOLLOW THIS IN THE VERY SHORT TERM. THIS WILL OBVIOUSLY HAVE
IMPLICATIONS ON THE HOURLY TEMP TRENDS.

THE ARCTIC FRONT IS WELL MARKED WITH THE CLOUDS EDGE PUSHING
SOUTH OVER SOUTHERN CANADA..WILL WORK INTO OUR NORTHERN AREAS
THIS AFTERNOON. WILL USE MORE OF A MODEL DIURNAL TEMP TREND TODAY
WITH HIGHS REACHED EARLY IN THE FAR NORTHWEST ALONG WITH THE CLOUD
ISSUES IN THE SOUTH. STILL A DECENT CHANCE OF 40S FOR HIGHS IN THE
SOUTH. SOME MINOR LIFT WITH THE FRONT TONIGHT...AND THERE IS A
HINT OF PV ADVECTION LATE TONIGHT OVER FAR SOUTHERN MN FROM THE
SYSTEM TO OUR SOUTHWEST. WILL KEEP THE FLURRIES IN THE FORECAST
TONIGHT AND TUESDAY MORNING WITH THE FRONT AND WAIT ON THE
POSSIBILITY OF A SLIGHT CHANCE POP IN THE FAR SOUTH. THERE IS A
MINOR RISK OF FREEZING DRIZZLE WITH LACK OF MID LEVEL MOISTURE
UNTIL TUESDAY MORNING...BUT WITH A TIMING AN LOCATION
ISSUE...WILL WAIT ON THAT AS WELL.

A STRONGER FRONT STILL FORECAST TO AFFECT THE AREA THURSDAY AND
FRIDAY AND THE ECMWF HAS COME AROUND A LITTLE MORE IN LINE TO THE
GFS/GEM WITH THE STRENGTH. STILL A FAIR AMOUNT OF UNCERTAINTY IN
THE GFS ENSEMBLE TEMPS STARTING FRIDAY AND CONTINUING INTO THE
WEEKEND. EVEN THOUGH THE ECMWF LOOKS COLD FOR FRIDAY...IT`S TREND
FOR A GLANCING BLOW IS STILL THERE WITH A FLATTENING OF THE RIDGE
OUT WEST DURING THE WEEKEND. OUR CURRENT BLENDED FORECAST FOR
FRIDAY TEMPS MAY BE A BIT HIGH BUT THAT CAN STILL BE ADDRESSED IN
THE NEXT DAY OR TWO.

&&

.AVIATION.../12Z TAF ISSUANCE/

AREA OF IFR/LIFR DRIFTING SLOWLY EAST ABOUT 7 KNOTS THIS MORNING.
SOME CONCERN IFR REDEVELOPING TO THE SOUTHWEST AND MAY AFFECT EAST
CENTRAL MN/WESTERN WI LATER THIS MORNING.  WILL LEAVE SOME SCT LOW
CLOUDS IN THE EAST...WITH CLEARING AT KRNH BY 14Z OR SO.  NOT VERY
CONFIDENT WITH CLEARING AT KEAU...BUT WILL CONTINUE TREND OF
PREVIOUS FORECAST OF AROUND 19Z.  OTHER CONCERN IS COLD FRONT
DROPPING ACROSS THE REGION THIS AFTERNOON.  SHOULD CLEAR MOST AREAS
BY 00Z.  LOW CLOUDS CURRENTLY LAG THE FRONT...INTO SOUTHERN CANADA.
MAY SEE SOME DEVELOPMENT DURING THE MORNING CLOSER TO THE FRONT..SO
WILL CONTINUE TREND OF DEVELOPING MVFR CIGS WITH PASSAGE OF THE COLD
FRONT.  SOME LOWER CLOUDS DEVELOPING INTO NORTHEAST MN NOW.  LOOKS
LIKE THERE COULD BE A SHOT OF FLURRIES WITH THE LOWER CLOUDS...AND
MENTIONED THAT AT KRWF FOR NOW....MAINLY IN THE 02Z-08Z PERIOD.  MAY
SEE SOME BREAKS DEVELOPING IN THE KAXN BY MORNING...BUT WILL KEEP
MVFR CEILINGS ELSEWHERE.  SOUTHWEST TO WEST WINDS AHEAD OF
FRONT...BECOMING NORTHWEST TO NORTH AND A BIT GUSTY WITH
FROPA.

KMSP...LIFR CEILINGS CLEARED THE AIRPORT AND SHOULD REMAIN SO
THROUGH THE DAY.  SOME SMALL CHANCE OF LOWER CLOUDS LIFTING CLOSE TO
THE AIRPORT FROM THE SOUTHWEST LATER THIS MORNING...BUT WILL LEAVE
SCT FOR NOW.  EXPECT VSBYS TO CLEAR THROUGH 15Z AS WELL.  COLD FRONT
SWEEPS INTO THE AREA AROUND 22Z...THEN MVFR CEILINGS MOVING IN ABOUT
01Z.  MAY SEE SOME FLURRIES BUT NOT EXPECTED TO BE SIGNIFICANT SOME
LEFT THEM OUT FOR NOW.  WILL KEEP MVFR IN THROUGH THE TAF PERIOD.
SOUTHWEST TO WEST WINDS LESS THAN 10 KNOTS BECOMING NORTHWEST AND
NORTH WITH FROPA...AND A BIT GUSTY INTO THE EVENING AS COLD ADVECTION
CONTINUES.

&&

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

$$

JPR/DWE









AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

 322 AM CST MON FEB 6 2012

.DISCUSSION...

STILL A COMPLICATED CLOUD TREND THIS MORNING. THERE DOES SEEM TO
BE A BIT STRONGER EASTWARD PUSH OF THE CLOUD EDGE WEST OF MSP PER
THE MORE WEST COMPONENT SEEN IN THE LOW LEVELS. A DIFFERENT STORY
OVER FAR SOUTHERN MN. THAT EDGE HAS A SLOW NORTHWARD DRIFT WHICH
MAY CONTINUE AND PROBABLY  KEEP SOUTH CENTRAL MN AND PARTS OF
WEST CENTRAL WI IN THE CLOUDS THOUGH THE MORNING. THE HRRR HAS HAD
THE BEST TREND ON THE LOW CLOUDS SINCE YESTERDAY...SO WILL TRY TO
FOLLOW THIS IN THE VERY SHORT TERM. THIS WILL OBVIOUSLY HAVE
IMPLICATIONS ON THE HOURLY TEMP TRENDS.

THE ARCTIC FRONT IS WELL MARKED WITH THE CLOUDS EDGE PUSHING
SOUTH OVER SOUTHERN CANADA..WILL WORK INTO OUR NORTHERN AREAS
THIS AFTERNOON. WILL USE MORE OF A MODEL DIURNAL TEMP TREND TODAY
WITH HIGHS REACHED EARLY IN THE FAR NORTHWEST ALONG WITH THE CLOUD
ISSUES IN THE SOUTH. STILL A DECENT CHANCE OF 40S FOR HIGHS IN THE
SOUTH. SOME MINOR LIFT WITH THE FRONT TONIGHT...AND THERE IS A
HINT OF PV ADVECTION LATE TONIGHT OVER FAR SOUTHERN MN FROM THE
SYSTEM TO OUR SOUTHWEST. WILL KEEP THE FLURRIES IN THE FORECAST
TONIGHT AND TUESDAY MORNING WITH THE FRONT AND WAIT ON THE
POSSIBILITY OF A SLIGHT CHANCE POP IN THE FAR SOUTH. THERE IS A
MINOR RISK OF FREEZING DRIZZLE WITH LACK OF MID LEVEL MOISTURE
UNTIL TUESDAY MORNING...BUT WITH A TIMING AN LOCATION
ISSUE...WILL WAIT ON THAT AS WELL.

A STRONGER FRONT STILL FORECAST TO AFFECT THE AREA THURSDAY AND
FRIDAY AND THE ECMWF HAS COME AROUND A LITTLE MORE IN LINE TO THE
GFS/GEM WITH THE STRENGTH. STILL A FAIR AMOUNT OF UNCERTAINTY IN
THE GFS ENSEMBLE TEMPS STARTING FRIDAY AND CONTINUING INTO THE
WEEKEND. EVEN THOUGH THE ECMWF LOOKS COLD FOR FRIDAY...IT`S TREND
FOR A GLANCING BLOW IS STILL THERE WITH A FLATTENING OF THE RIDGE
OUT WEST DURING THE WEEKEND. OUR CURRENT BLENDED FORECAST FOR
FRIDAY TEMPS MAY BE A BIT HIGH BUT THAT CAN STILL BE ADDRESSED IN
THE NEXT DAY OR TWO.

&&

.AVIATION.../06Z TAF ISSUANCE/

PERSISTENT LOW CLDS/FG ACROSS THE EASTERN FA IS THE MAIN CONCERN
IS THE SHORT TERM AND WHETHER STRONGER SW FLOW IN THE BOUNDARY
LAYER DEVELOPING...WILL ALLOW FOR THE CLDS TO MOVE OUT DURING THE
NEXT 6 TO 12 HRS.

BASED ON CURRENT SATELLITE TRENDS OVER THE PAST FEW HRS...AND
BOUNDARY LAYER MOISTURE REMAINING HIGH...MSP/RNH/EAU WILL LIKELY
CONTINUE THE IFR/LIFR CIGS THRU 12Z...WITH A SLOW EROSION FROM THE
WEST/NW AS A COLD FRONT MOVES ACROSS THE AREA BY AFTN.

LATEST RUC HAS A GOOD HANDLE ON THE LOW LEVEL MOISTURE AND
ASSOCIATED CLDS...BUT IT CONTINUES TO DECREASE THE CLDS FROM THE
WEST TOO FAST THAN CURRENTLY INDICATED. WITH SOME UNCERTAINTY PAST
12Z...WILL HOLD ON TO LIFR/IFR CIGS AT RNH/EAU UNTIL WNDS SHIFT TO
THE W/NW BY NOON. RWF/AXN/STC WILL LIKELY SEE SOME BR/FG THIS
MORNING...BUT ENOUGH MIXING IN THE BOUNDARY LAYER SHOULD PRECLUDE
ANY SIGNIFICANT DENSE FG BY MORNING. CIGS ACROSS FAR SW MN MAY
AFFECT RWF BY 12Z...BUT WNDS ARE NOT CONDUCIVE FROM THE BOUNDARY
LAYER TO ADV THESE CLDS TO THE NE THIS MORNING. TIMING OF THE
COLD FRONT AND ASSOCIATED MVFR CIGS ARE CLOSE TO PREVIOUS TAFS.
THE ONSET OF MVFR CIGS MAY BE A BIT TOO FAST BASED ON UPSTREAM
CLDS. WNDS WILL BECOME W/WNW THIS DURING THE MORNING...THEN SHIFT
TO THE N/NNE AND INCREASE DURING THE AFTN/EVENING.

MSP...THRU 12Z...IFR CIGS AND VSBYS ARND 3-5SM WILL CONTINUE. BY
12Z...SOME UNCERTAINTY EXIST IF THE WESTERN EDGE OF THE CLDS WILL
MOVE FAR ENOUGH EAST TO BECOME SCT008 AT THE AIR FIELD.

THEREFORE...INCLUDED A TEMPORARY PERIOD OF POSSIBLE VFR BETWEEN
11-15Z. MVFR CIGS WILL ONCE AGAIN ADV BACK ACROSS THE REGION BY
AFTN AS A COLD FRONT MOVES SOUTHWARD. WNDS WILL BECOME MORE W/WNW
BY 12Z...THEN SHIFT TO THE NW AFT 18Z. WNDS SHOULD INCREASE IN SPD
BY 22-01Z...WITH A FEW GUSTS OVER 20 KTS POSSIBLE.

.TUE...MVFR CIGS EARLY WITH -SN POSSIBLE.
.WED...VFR.
..JLT..



&&

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

$$

JPR/JLT






AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

 1126 PM CST SUN FEB 5 2012

.DISCUSSION...

THIS FORECAST NOT MUCH MORE THAN A CLOUD AND TEMPERATURE
FORECAST...WITH A CONTINUED DRY PATTERN EXPECTED FOR THE NEXT WEEK.
MILD CONDITIONS WILL PERSISTENT THROUGH MONDAY...WITH A COOL DOWN
EXPECTED FOR TUESDAY THROUGH FRIDAY...WITH A WARM UP OF SOME DEGREE
COMING FOR THE WEEKEND.

RATHER UNIQUE UPPER AIR PATTERN EXISTS THIS AFTERNOON...WITH A REX
BLOCK PATTERN IN PLACE ACROSS THE ROCKIES. MPX CWA CAUGHT IN A WEAK
FORCING AREA BETWEEN THE CUT OFF LOW OVER THE ROCKIES...THE REMNANTS
OF THE PLAINS SNOW STORM OVER MO...AND THE MAIN UPPER FLOW ACROSS MB
AND ONT. THIS HAS ONCE AGAIN LEFT LOW STRATUS ADRIFT ACROSS THE AREA
TODAY...WITHOUT MUCH FORCING TO GET RID OF IT. PIREPS THIS MORNING
SHOWED CLOUDS OVER THE TWIN CITIES WERE AROUND 2K FT DEEP...AND AS A
RESULT...HAS BEEN A SLOW GO IN CLEARING THINGS OUT THIS AFTERNOON.
FOR SKY GRIDS...ABOUT THE ONLY BIT OF GUIDANCE THAT HAD ANY IDEA THE
STRATUS WAS OUT THERE WAS THE LOCAL MPX WRF...SO FOLLOWED IT FOR
SLOWLY WORKING CLOUDS SE ACROSS THE AREA TONIGHT. HAVE CLOUDY
CONDITIONS REMAINING ACROSS SE CWA INTO MONDAY MORNING...WITH MO
CLEAR TO PRTLY CLOUDY CONDITIONS ELSEWHERE BY MONDAY MORNING...BUT
MUST ADMIT...NOT COMPLETELY CONVINCED THAT CLOUDS WILL NOT START
BUILDING BACK WEST/NORTH ONCE THE SUN SETS. REGARDLESS OF CLOUD
COVER...TONIGHT WILL BE A MILD ONE...AS BUBBLE OF WARM AIR THAT WAS
OFF TO OUR NW THIS MORNING /+8C AT H85 AT THE PAS...MB AT 12Z/ WILL
BE MOVING OVHD TONIGHT OUT AHEAD OF THE ARCTIC FRONT COMING MONDAY.

BY 12Z MONDAY MORNING...COLD FRONT WILL BE ALONG THE US-2 CORRIDOR
AND WILL BE DOWN ALONG THE IA BORDER BY 00Z ACCORDING TO SREF
TIMING. THE ONLY TWO REAL CONCERNS WITH THIS FRONT ARE HOW WARM DOES
IT GET ACROSS SRN MN...FOLLOWED BY HOW QUICKLY DOES STRATUS MAKE ITS
RETURN IN ITS WAKE. ASSUMING STATUS DOES NOT FILL BACK IN TO THE
WEST/NORTH TONIGHT...SHOULD GET A GOOD PERIOD OF SUNSHINE INTO THE
AFTERNOON ACROSS THE SRN HALF OF THE AREA MONDAY...WITH HIGHS EASILY
PUSHING INTO THE LOW 40S GIVEN THE MILD START IN THE MID/UPPER 20S.
GIVEN FRONTAL TIMING...ALSO HAVE A NON-DIURNAL TEMPERATURE CURVE
BASED OFF OF THE SREF...WHICH HELD TEMPERATURES STEADY IN CAA ACROSS
THE NW CWA IN THE AFTERNOON. ASSUMING CLOUDS DO NOT MESS THINGS UP
TOMORROW...SHOULD HAVE A NICE GRADIENT IN HIGHS...WITH UPPER 20S UP
AROUND AXN AND MID 40S DOWN ALONG I-90.

FOR MONDAY NIGHT...MODELS ALL IN GOOD AGREEMENT ON STRATUS COMING
BACK IN BEHIND THE FRONT. WHERE DISAGREEMENTS COME ABOUT IS HOW
QUICKLY TO IMPROVE SKIES GOING INTO THE DAY ON TUESDAY. NAM
BASICALLY KEEPS THE ENTIRE AREA UNDER THE STRATUS THROUGH
WEDNESDAY...WHILE THE GFS/ECMWF WOULD SUGGEST SKIES WILL MOSTLY
CLEAR OUT BY 12Z WEDNESDAY. MODELS TEND TO BE TOO AGGRESSIVE WITH
CLEARING OUT OF CLOUDS...SO DID FAVOR THINGS TOWARD THE SLOWER NAM.
BESIDE THE CLOUDS...TEMPERATURES WILL BE NOTICEABLY COLDER
TUESDAY/WEDNESDAY AS H85 TEMPS TUMBLE DOWN TO AROUND -10C...WITH
HIGHS GETTING BACK DOWN TO A LITTLE BIT BELOW NORMAL FOR THE FIRST
TIME IN A COUPLE OF WEEKS.

BESIDE THE CLOUD COVER...THE NAM IN PARTICULAR IS SPITTING OUT SOME
LIGHT QPF MONDAY NIGHT...SO DID ADD SOME SCT FLURRY WORDING TO THE
FORECAST. LACK OF DEEP FORCING/MOISTURE SHOULD KEEP IT FROM GETTING
ANY WORSE THAN THAT.

NEXT REINFORCING SHOT OF COLD AIR WILL COME DOWN THURSDAY
NIGHT...BUT OUT AHEAD OF THIS FRONT...WILL HAVE A QUICK WARMUP FOR
THURSDAY AS A MILD WSW FLOW RETURNS. 1040 MB HIGH WILL SETTLE OVER
THE AREA FOR FRIDAY...WITH A QUICK RETREAT IN TEMPS EXPECTED FOR THE
END OF THE WEEK.

BIG DISAGREEMENTS BETWEEN THE GFS/ECMWF START SHOWING UP FOR NEXT
WEEKEND...WITH THE ECMWF STARTING TO BUILD A DEEP TROUGH OVER THE
ROCKY MOUNTAINS...WHILE THE GFS KEEPS SOME VESTIGE OF THE RIDGE
GOING ALONG THE WEST COAST. BY SATURDAY AFTERNOON...ECMWF HAS H85
TEMPS BACK UP AROUND +5C ACROSS WRN MN...WHEREAS THE GFS HAS THINGS
SIGNIFICANTLY COLDER...WITH H85 TEMPS AT THE SAME TIME DOWN AROUND
-10C. THE ECMWF IDEA WOULD HAVE HIGHS PUSHING 50 AGAIN OUT IN WRN MN
BY SUNDAY...WHILE THE GFS WOULD KEEP THINGS BACK DOWN AROUND 30.
WITH ALL OF THE UNCERTAINTY...STUCK CLOSE THE THE CENTRAL REGION
BLENDED GUIDANCE...WHICH BASICALLY TAKES THE MIDDLE ROAD FOR THE
WEEKEND.

&&

.AVIATION.../06Z TAF ISSUANCE/

PERSISTENT LOW CLDS/FG ACROSS THE EASTERN FA IS THE MAIN CONCERN
IS THE SHORT TERM AND WHETHER STRONGER SW FLOW IN THE BOUNDARY
LAYER DEVELOPING...WILL ALLOW FOR THE CLDS TO MOVE OUT DURING THE
NEXT 6 TO 12 HRS.

BASED ON CURRENT SATELLITE TRENDS OVER THE PAST FEW HRS...AND
BOUNDARY LAYER MOISTURE REMAINING HIGH...MSP/RNH/EAU WILL LIKELY
CONTINUE THE IFR/LIFR CIGS THRU 12Z...WITH A SLOW EROSION FROM THE
WEST/NW AS A COLD FRONT MOVES ACROSS THE AREA BY AFTN.

LATEST RUC HAS A GOOD HANDLE ON THE LOW LEVEL MOISTURE AND
ASSOCIATED CLDS...BUT IT CONTINUES TO DECREASE THE CLDS FROM THE
WEST TOO FAST THAN CURRENTLY INDICATED. WITH SOME UNCERTAINTY PAST
12Z...WILL HOLD ON TO LIFR/IFR CIGS AT RNH/EAU UNTIL WNDS SHIFT TO
THE W/NW BY NOON. RWF/AXN/STC WILL LIKELY SEE SOME BR/FG THIS
MORNING...BUT ENOUGH MIXING IN THE BOUNDARY LAYER SHOULD PRECLUDE
ANY SIGNIFICANT DENSE FG BY MORNING. CIGS ACROSS FAR SW MN MAY
AFFECT RWF BY 12Z...BUT WNDS ARE NOT CONDUCIVE FROM THE BOUNDARY
LAYER TO ADV THESE CLDS TO THE NE THIS MORNING. TIMING OF THE
COLD FRONT AND ASSOCIATED MVFR CIGS ARE CLOSE TO PREVIOUS TAFS.
THE ONSET OF MVFR CIGS MAY BE A BIT TOO FAST BASED ON UPSTREAM
CLDS. WNDS WILL BECOME W/WNW THIS DURING THE MORNING...THEN SHIFT
TO THE N/NNE AND INCREASE DURING THE AFTN/EVENING.

MSP...THRU 12Z...IFR CIGS AND VSBYS ARND 3-5SM WILL CONTINUE. BY
12Z...SOME UNCERTAINTY EXIST IF THE WESTERN EDGE OF THE CLDS WILL
MOVE FAR ENOUGH EAST TO BECOME SCT008 AT THE AIR FIELD.

THEREFORE...INCLUDED A TEMPORARY PERIOD OF POSSIBLE VFR BETWEEN
11-15Z. MVFR CIGS WILL ONCE AGAIN ADV BACK ACROSS THE REGION BY
AFTN AS A COLD FRONT MOVES SOUTHWARD. WNDS WILL BECOME MORE W/WNW
BY 12Z...THEN SHIFT TO THE NW AFT 18Z. WNDS SHOULD INCREASE IN SPD
BY 22-01Z...WITH A FEW GUSTS OVER 20 KTS POSSIBLE.

.TUE...MVFR CIGS EARLY WITH -SN POSSIBLE.
.WED...VFR.
..JLT..

&&

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

$$

MPG/JLT





AREA FORECAST DISCUSSION...UPDATED

NWS GLASGOW MT

 914 AM MST MON FEB 6 2012

.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH WEDNESDAY...

SENT AN UPDATE THIS MORNING TO REMOVE MORNING WORDING OF FREEZING
FOG AND TO ADD SOME FLURRIES PER CURRENT RADAR TRENDS. MOST OF THE
PRECIPITATION NORTH OF THE LITTLE ROCKIES WILL LIKELY REMAIN VIRGA
BUT FOR POINTS AROUND AND SOUTH OF THE LITTLE ROCKIES MAY SEE
SMALL ACCUMULATIONS OF SNOW TODAY AS THE COLD FRONT CONTINUES TO
PUSH SOUTHWARD. BMICKELSON

PREVIOUS SHORT TERM DISCUSSION...REX BLOCK OVER THE W STATES/W
CANADA CONTINUES...HOWEVER NE MT ON THE W EDGE OF NNW FLOW AROUND
THE LARGE HUDSON BAY UPPER LOW COMPLEX. THIS HAS BEEN BRINGING
COLDER AIR INTO OUR AREA...WHICH STARTED LAST NIGHT...WHICH WILL
CONTINUE TODAY...RESULTING IN HIGHS 15F OR MORE COLDER THAN
YESTERDAY. STRONGEST 850 MB WINDS OF UP TO 30 KT IN OUR N THIS
MORNING. WE WILL BE ALMOST DRY ADIABATICALLY MIXED...AND ALMOST TO
THIS LEVEL...SO A LITTLE BIT WINDY THIS MORNING IN COLD ADVECTION
PATTERN.

THE COLDER AIR MASS IS ASSOCIATED WITH A 1045 MB SURFACE HIGH
PRESSURE CENTERED ON NE AB/NW SK BORDER THAN WILL MOVE TO OUR NE
BORDER LATE TONIGHT AND TUE. THE AIR MASS WITH THIS IS MOIST IN
LOWER LEVELS...BUT NOT PARTICULARLY COLD FOR THIS TIME OF YEAR.

OBS INDICATE NARROW TEMP/DEW POINT SPREADS IN OUR FORECAST AREA
OVERNIGHT AND EARLY THIS MORN...AND SIGNS OF VISIBILITY
REDUCTION. THERE ARE ALSO AREAS OF MULTIPLE AND EXPANDING LOWER
CLOUD LAYERS APPROACHING FROM THE NW AND N. MODELS INDICATE THIS
EXPANSION AS WELL AS LOWERING CEILINGS WILL CONTINUE...WITH RUC
AND HRRR SEEMING TO DO THE BEST WITH IT. THUS EXPECT SOME HIGHER
ELEVATIONS WILL END UP WITH FOG FROM THIS. ENOUGH WIND TO KEEP
LOWER ELEVATION FOG MORE PATCHY AND LESS VISIBILITY REDUCTION.
WILL ISSUE A HAZARDOUS WEATHER OUTLOOK (HWO).

THIS OVERCAST/FOG WILL LIFT SOME THIS AFTERNOON...THEN CLEAR OUT
TONIGHT BEHIND THE PASSAGE OF AN UPPER TROUGH...AND AS THE SURFACE
HIGH PUSHES IN. COLDER PART OF THE AIR MASS IS TONIGHT AND TUE WITH
THICKNESSES DOWN TO 510 DM AND 850 MB TEMPS AS LOW AS -13C IN OUR
AREA. MODELS ARE IN GOOD AGREEMENT DURING THE ENTIRE PERIOD.

THE SURFACE HIGH MOVES SE OUT OF THE AREA WED...ALLOWING FOR THE
WARMING OF THE AIR MASS. IT LEAVES BEHIND RATHER WEAK SURFACE
PRESSURES THOUGH AND CONTINUED DRY AIR MASS. RESULT IS SUNNY AND
A LITTLE WARMER WED WITH WINDS ON THE LIGHT SIDE. MODELS ARE
QUITE A BIT SLOWER THAN YESTERDAY WITH THE APPROACH OF THE NEXT
COLD FRONT FROM THE N. SIMONSEN

.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...
THE EXTENDED BEGINS WITH A LARGE UPPER LOW OVER NORTHERN QUEBEC
PROVINCE... RIDGING OVER THE WEST COAST WITH ANOTHER UPPER LOW
OVER THE KAMCHATKA PENINSULA IN FAR EASTERN RUSSIA. THE WEST COAST
RIDGE EXTENDS WELL INTO THE ARCTIC PROVIDING DRY NORTHERLY FLOW
FOR NORTHEAST MONTANA. AS THE FORECAST MOVES INTO THE WEEKEND THE
UPPER LOW OVER QUEBEC WEAKENS AND LIFTS INTO GREENLAND AS THE
KAMCHATKAN LOW MOVES INTO THE WESTERN BERING SEA. THE UPPER LOWS
ACTION OF PULLING APART ALLOWS THE WEST COAST RIDGE TO BREAK DOWN.
THE RESULT IS A MORE ZONAL FLOW KEEPING THE WEATHER PATTERN IN THE
DRY AND ABOVE NORMAL RANGE. MONDAY AND TUESDAY A TROUGH OF LOW
PRESSURE IS FORECAST TO DIG INTO THE AREA BRINGING A SLIGHT
POSSIBLY OF PRECIPITATION.

MODEL CONFIDENCE IS FAIR TO ABOVE NORMAL AT THE START OF THE
EXTENDED THROUGH SATURDAY AT 12Z WHEN THE MODELS HANDLE AN UPPER
LOW MOVING ONSHORE IN CENTRAL CALIFORNIA VERY DIFFERENTLY. LIKE
THE EC HANDLING OF IT AS A WEAK TROUGH OVER THE GEM/S OVER
DEEPENING AND THE GFS/S SLOWER MOVEMENT. FOR DAY 6 THROUGH DAY 8
THE GFS AND EC ARE SIMILAR FOR FAIR MODEL CONFIDENCE...THE GEM HAS
GONE IN A DIFFERENT DIRECTION.

TEMPS/PRECIPITATION FOR THE EXTENDED DOES NOT APPEAR TO HAVE MUCH
CHANGE FROM THE PAST COUPLE OF WEEKS. NO MAJOR CHANGE EXPECTED IN
THE EXTENDED.     PROTON

&&

.AVIATION...
A WIDE BAND OF MVFR CLOUDS WILL SLIDE ACROSS THE REGION THIS
MORNING AND THROUGH EARLY AFTERNOON. EXPECT THESE CLOUDS TO CLEAR
THE REGION THIS EVENING FOR A RETURN OF VFR CONDITIONS WITH HIGH
PRESSURE OVER EASTERN MONTANA INTO TUESDAY. RAE

&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

WEATHER.GOV/GLASGOW






AREA FORECAST DISCUSSION

NWS GLASGOW MT

 416 AM MST MON FEB 6 2012

.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH WEDNESDAY...
REX BLOCK OVER THE W STATES/W CANADA CONTINUES...HOWEVER NE MT ON
THE W EDGE OF NNW FLOW AROUND THE LARGE HUDSON BAY UPPER LOW
COMPLEX. THIS HAS BEEN BRINGING COLDER AIR INTO OUR AREA...WHICH
STARTED LAST NIGHT...WHICH WILL CONTINUE TODAY...RESULTING IN
HIGHS 15F OR MORE COLDER THAN YESTERDAY. STRONGEST 850 MB WINDS OF
UP TO 30 KT IN OUR N THIS MORNING. WE WILL BE ALMOST DRY
ADIABATICALLY MIXED...AND ALMOST TO THIS LEVEL...SO A LITTLE BIT
WINDY THIS MORNING IN COLD ADVECTION PATTERN.

THE COLDER AIRMASS IS ASSOCIATED WITH A 1045 MB SURFACE HIGH
PRESSURE CENTERED ON NE AB/NW SK BORDER THAN WILL MOVE TO OUR NE
BORDER LATE TONIGHT AND TUE. THE AIRMASS WITH THIS IS MOIST IN
LOWER LEVELS...BUT NOT PARTICULARLY COLD FOR THIS TIME OF YEAR.

OBS INDICATE NARROW TEMP/DEW POINT SPREADS IN OUR FORECAST AREA
OVERNIGHT AND EARLY THIS MORN...AND SIGNS OF VISIBILITY
REDUCTION. THERE ARE ALSO AREAS OF MULTIPLE AND EXPANDING LOWER
CLOUD LAYERS APPROACHING FROM THE NW AND N. MODELS INDICATE THIS
EXPANSION AS WELL AS LOWERING CEILINGS WILL CONTINUE...WITH RUC
AND HRRR SEEMING TO DO THE BEST WITH IT. THUS EXPECT SOME HIGHER
ELEVATIONS WILL END UP WITH FOG FROM THIS. ENOUGH WIND TO KEEP
LOWER ELEVATION FOG MORE PATCHY AND LESS VISIBILITY REDUCTION.
WILL ISSUE A HAZRDOUS WEATHER OUTLOOK (HWO).

THIS OVERCAST/FOG WILL LIFT SOME THIS AFTERNOON...THEN CLEAR OUT
TONIGHT BEHIND THE PASSAGE OF AN UPPER TROUGH...AND AS THE SURFACE
HIGH PUSHES IN. COLDER PART OF THE AIRMASS IS TONIGHT AND TUE WITH
THICKNESSES DOWN TO 510 DM AND 850 MB TEMPS AS LOW AS -13C IN OUR
AREA. MODELS ARE IN GOOD AGREEMENT DURING THE ENTIRE PERIOD.

THE SURFACE HIGH MOVES SE OUT OF THE AREA WED...ALLOWING FOR THE
WARMING OF THE AIRMASS. IT LEAVES BEHIND RATHER WEAK SURFACE
PRESSURES THOUGH AND CONTINUED DRY AIRMASS. RESULT IS SUNNY AND
A LITTLE WARMER WED WITH WINDS ON THE LIGHT SIDE. MODELS ARE
QUITE A BIT SLOWER THAN YESTERDAY WITH THE APPROACH OF THE NEXT
COLD FRONT FROM THE N. SIMONSEN

.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...
THE EXTENDED BEGINS WITH A LARGE UPPER LOW OVER NORTHERN QUEBEC
PROVINCE... RIDGING OVER THE WEST COAST WITH ANOTHER UPPER LOW
OVER THE KAMCHATAN PENINSULA IN FAR EASTERN RUSSIA. THE WEST COAST
RIDGE EXTENDS WELL INTO THE ARCTIC PROVIDING DRY NORTHERLY FLOW
FOR NORTHEAST MONTANA. AS THE FORECAST MOVES INTO THE WEEKEND THE
UPPER LOW OVER QUEBEC WEAKENS AND LIFTS INTO GREENLAND AS THE
KAMCHATKAN LOW MOVES INTO THE WESTERN BERING SEA. THE UPPER LOWS
ACTION OF PULLING APART ALLOWS THE WEST COAST RIDGE TO BREAK DOWN.
THE RESULT IS A MORE ZONAL FLOW KEEPING THE WEATHER PATTERN IN THE
DRY AND ABOVE NORMAL RANGE. MONDAY AND TUESDAY A TROUGH OF LOW
PRESSURE IS FORECAST TO DIG INTO THE AREA BRINGING A SLIGHT
POSSIBLY OF PRECIPITATION.

MODEL CONFIDENCE IS FAIR TO ABOVE NORMAL AT THE START OF THE
EXTENDED THROUGH SATURDAY AT 12Z WHEN THE MODELS HANDLE AN UPPER
LOW MOVING ONSHORE IN CENTRAL CALIFORNIA VERY DIFFERENTLY. LIKE
THE EC HANDLING OF IT AS A WEAK TROUGH OVER THE GEM/S OVER
DEEPENING AND THE GFS/S SLOWER MOVEMENT. FOR DAY 6 THROUGH DAY 8
THE GFS AND EC ARE SIMILAR FOR FAIR MODEL CONFIDENCE...THE GEM HAS
GONE IN A DIFFERENT DIRECTION.

TEMPS/PRECIPITATION FOR THE EXTENDED DOES NOT APPEAR TO HAVE MUCH
CHANGE FROM THE PAST COUPLE OF WEEKS. NO MAJOR CHANGE EXPECTED IN
THE EXTENDED.     PROTON

&&

.AVIATION...
MVFR HAS DEVELOPED IN SOME AREAS THIS MORNING. A LARGE MASS OF MID
LEVEL VFR CLOUDS HAS DEVELOPED AHEAD OF COLD FRONT ACROSS THE
CENTRAL PRAIRIE PROVINCES. OVER CENTRAL MONTANA A MVFR DECK OF
STRATUS HAS FORMED...HOWEVER WITH THE MID CLOUD MOVING DOWN DO
EXPECT IT TO LIFT IN VFR LEVELS. EARLY THIS MORNING DO EXPECT
POCKETS OF MVFR AND ISOLATED IFR CONDITIONS WITH RIVER VALLEY
FOG... AGAIN SHORT LIVED WITH THE MID CLOUDS MOVING DOWN. FOR THE
REST OF DAY INTO TONIGHT LOOK FOR VFR SKIES AND EASTERLY WINDS.   PROTON

&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

WEATHER.GOV/GLASGOW






AREA FORECAST DISCUSSION

NWS OMAHA/VALLEY NE

 1123 AM CST MON FEB 6 2012

.DISCUSSION...

WILL LET THE DENSE FOG ADVISORY FOR WESTERN IOWA EXPIRE ON SCHEDULE
AT 18Z.

&&

.AVIATION...18Z TAFS FOR KOMA...KLNK...KOFK.

SOMEWHAT COMPLICATED SET OF TAFS THIS CYCLE FOR A VARIETY OF
REASONS. SOME MVFR FOG WILL STILL BE POSSIBLE AT KOMA TIL ABOUT
19Z...AND COULD REDEVELOP THIS EVENING BEFORE A COLD FRONT
ARRIVES. OTHERWISE...THE MAIN FOCUS WOULD BE THE COLD FRONT...
SWITCHING WINDS FROM THE WEST SOUTHWEST AHEAD OF THE FRONT...TO
THE NORTHWEST BEHIND. ALSO EXPECTING MVFR CEILINGS TO DEVELOP
BEHIND THE COLD FRONT...AT KOFK BY ABOUT 05Z...AND KOMA/KLNK BY
08-09Z. ALSO HAVE SOME CONCERN FOR SOME PATCHY FREEZING DRIZZLE AT
KOFK 07-10Z...BEFORE DEEPER SATURATION ARRIVES RESULTING IN ICE
CRYSTAL DEVELOPMENT...WHICH COULD BRING SOME SNOW TO THE SITES
LATE IN THE TAF PERIOD WITH MVFR VISIBILITIES.

DEWALD

&&

.PREV DISCUSSION... /ISSUED 1001 AM CST MON FEB 6 2012/

DISCUSSION...
UPDATED THE FORECAST TO ALLOW THE DENSE FOG ADVISORY TO EXPIRE IN
EASTERN NEBRASKA...BUT EXTENDED UNTIL NOON FOR WESTERN IOWA...WHICH
REMAINS SOCKED IN WITH WIDE VISIBILITY OF 1/4 MILE OR LESS. WE ARE
SEEING AN EROSION ON THE WESTERN EDGE OF THE FOG/STRATUS...BUT IT
WILL STILL TAKE A COUPLE MORE HOURS. ALSO DROPPED TEMPERATURES IN
WESTERN IOWA WHERE THE CLOUDS WILL LINGER THE LONGEST. NO OTHER
CHANGES MADE AT THIS TIME.

WILL HAVE TO TAKE A LOOK AT EXPECTED WEATHER TONIGHT BEHIND A COLD
FRONT THAT WILL SURGE INTO THE FORECAST AREA. THIS WILL BRING LOW
CLOUDS BACK TO THE REGION...AND HAVE SOME CONCERN THAT UNTIL
DEEPER MOISTURE ARRIVES...THERE COULD BE SOME SPOTTY FREEZING
DRIZZLE IN NORTHEAST NEBRASKA FROM ABOUT 03Z-09Z THAT WE CURRENTLY
DON`T HAVE FORECAST.

DEWALD

PREV DISCUSSION... /ISSUED 733 AM CST MON FEB 6 2012/

UPDATE...

TAKING A LOOK AT LATEST OBSERVATIONS AND WEB CAMS...DENSE FOG IS
NOT PREVALENT IN OUR WESTERN COUNTIES. DENSE FOG ADVISORIES WEST
OF OUR AREA WERE CANCELLED EARLIER...SO WILL GO AHEAD AND CLEAR
WESTERN PARTS OF THE DENSE FOG ADVISORY. THE KOAX 12Z SOUNDING
SHOWED WEST OR SOUTHWEST WINDS OF 10-14 KNOTS JUST OFF THE SURFACE
SO THIS SHOULD HELP WITH THE FOG. WILL KEEP ADVISORY UNTIL 16Z FOR
EXTREME EASTERN NEBRASKA AND SOUTHWEST IOWA....

MILLER

PREV DISCUSSION... /ISSUED 520 AM CST MON FEB 6 2012/

AVIATION...
12Z TAFS FOR KOMA...KLNK...KOFK.

LOW CLOUDS AND FOG WILL BE THE MAIN CONCERNS AT LEAST THROUGH THE
MORNING HOURS. LIFR CONDITIONS SHOULD CONTINUE AT KOMA THROUGH AT
LEAST MID MORNING BUT SLOWLY IMPROVE TO VFR BY MID/LATE AFTERNOON.
FARTHER WEST AT KLNK AND KOFK...THE FOG WILL BE MORE VARIABLE THIS
MORNING. 13 KM RUC MODEL AND HIGH RESOLUTION RAPID REFRESH MODEL
BOTH SEEMED TO HAVE SOMEWHAT OF A HANDLE ON THE LOW CLOUDS.

WEST/SOUTHWEST WINDS SHOULD ALLOW FOR MAINLY VFR CONDITIONS FROM
MID AFTERNOON INTO THE EVENING WITH WEST OR SOUTHWEST LOW LEVEL
WINDS. IFR VSBYS COULD REFORM THIS EVENING FOR A WHILE...BUT DID
NOT MENTION AT THIS TIME. OTHERWISE...A COLD FRONT WILL PUSH
SOUTHWARD ACROSS THE AREA TONIGHT...SHIFTING WINDS TO THE NORTH.
LOOK FOR MVFR CEILINGS TO DEVELOP BEHIND THE FRONT. THERE COULD
ALSO BE SOME LIGHT SNOW OR FREEZING DRIZZLE.

MILLER

PREV DISCUSSION... /ISSUED 308 AM CST MON FEB 6 2012/

DISCUSSION...

MAIN FORECAST CHALLENGE WILL BE EXTENT OF STRATUS/FOG AND HOW MUCH
THIS CAN ERODE THROUGH THE DAY. FOCUS THEN SHIFTS TO INCOMING
COLD FRONT AND SMALL CHANCE OF PCPN TONIGHT INTO TUESDAY.

UPPER CLOSED LOW CURRENTLY OVER THE GREAT BASIN WILL OPEN AND
CONTINUE TO PUSH EAST TOWARD THE CENTRAL PLAINS TODAY WHILE A
SHORTWAVE TROF OVER SRN CANADA MOVES SOUTH INTO THE NRN PLAINS
TONIGHT. AT THE SFC...AREA OF HIGH PRESSURE IS CENTERED OVER THE
SOUTHERN PLAINS WITH CALM WINDS OVER THE ENTIRE CWA. DENSE FOG
FORMED EARLY LAST EVENING OVER SNOWPACK AND DO EXPECT FOG TO LIFT
BY MID-LATE MORNING. STRATUS DECK OVER THE EASTERN COUNTIES IS
EXPECTED TO HANG ON THRU MUCH OF THE MORNING AND PERHAPS EVEN
INTO THE AFTERNOON HOURS AS INDICATED BY LATEST HRRR MODEL RUNS.
WL EXTEND DENSE FOG ADVISORY UNTIL 16Z AS VISIBILITIES WL BE SLOW
TO IMPROVE. STRATUS IN ADDITION TO SNOWCOVER WL PLAY HAVOC ON HIGH
TEMPERATURES. HAVE FORECAST HIGHS NEAR OR JUST ABOVE FREEZING
TODAY.

CDFNT ASSOCIATED WITH SRN CANADIAN SHORTWAVE WL MOVE INTO THE REGION
EARLY THIS EVENING AS WEAKENING SHORTWAVE ENERGY FROM GREAT BASIN
LOW APPROACHES THE AREA. LIGHT PCPN STILL ON TRACK TO DEVELOP ACROSS
KS/MO AND INTO SERN NEB. FORECAST SOUNDINGS INDICATE THE POTENTIAL
FOR LIGHT FREEZING DRIZZLE INTITIALLY AND THEN A QUICK CHANGE TO
LIGHT SNOW IF NOT JUST FLURRIES. PERIOD OF FORCING IS BRIEF AND
ONLY EXPECT LIGHT SNOWFALL ACCUMULATIONS OF GENERALLY A TENTH OF
AN INCH OR SO LATE TONIGHT INTO TUESDAY MORNING.

DRY WEATHER IS EXPECTED THEREAFTER AS SFC HIGH PRESSURE MOVES
OVER THE REGION ON WEDNESDAY. A STRONG COLD FRONT WILL SURGE SOUTH
THROUGH THE AREA LATE THURSDAY. HAVE COOLED TEMPS SIGNIFICANTLY
OVER THE WEEKEND TO ACCOUNT FOR THIS SURGE OF COLD AIR.

KERN

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR IAZ043-055-056-069-
     079-080-090-091.

&&

$$

99/99




AREA FORECAST DISCUSSION

NWS OMAHA/VALLEY NE

 1001 AM CST MON FEB 6 2012

.DISCUSSION...
UPDATED THE FORECAST TO ALLOW THE DENSE FOG ADVISORY TO EXPIRE IN
EASTERN NEBRASKA...BUT EXTENDED UNTIL NOON FOR WESTERN IOWA...WHICH
REMAINS SOCKED IN WITH WIDE VISIBILITY OF 1/4 MILE OR LESS. WE ARE
SEEING AN EROSION ON THE WESTERN EDGE OF THE FOG/STRATUS...BUT IT
WILL STILL TAKE A COUPLE MORE HOURS. ALSO DROPPED TEMPERATURES IN
WESTERN IOWA WHERE THE CLOUDS WILL LINGER THE LONGEST. NO OTHER
CHANGES MADE AT THIS TIME.

WILL HAVE TO TAKE A LOOK AT EXPECTED WEATHER TONIGHT BEHIND A COLD
FRONT THAT WILL SURGE INTO THE FORECAST AREA. THIS WILL BRING LOW
CLOUDS BACK TO THE REGION...AND HAVE SOME CONCERN THAT UNTIL
DEEPER MOISTURE ARRIVES...THERE COULD BE SOME SPOTTY FREEZING
DRIZZLE IN NORTHEAST NEBRASKA FROM ABOUT 03Z-09Z THAT WE CURRENTLY
DON`T HAVE FORECAST.

DEWALD

&&

.PREV DISCUSSION... /ISSUED 733 AM CST MON FEB 6 2012/

UPDATE...

TAKING A LOOK AT LATEST OBSERVATIONS AND WEB CAMS...DENSE FOG IS
NOT PREVALENT IN OUR WESTERN COUNTIES. DENSE FOG ADVISORIES WEST
OF OUR AREA WERE CANCELLED EARLIER...SO WILL GO AHEAD AND CLEAR
WESTERN PARTS OF THE DENSE FOG ADVISORY. THE KOAX 12Z SOUNDING
SHOWED WEST OR SOUTHWEST WINDS OF 10-14 KNOTS JUST OFF THE SURFACE
SO THIS SHOULD HELP WITH THE FOG. WILL KEEP ADVISORY UNTIL 16Z FOR
EXTREME EASTERN NEBRASKA AND SOUTHWEST IOWA....

MILLER

PREV DISCUSSION... /ISSUED 520 AM CST MON FEB 6 2012/

AVIATION...
12Z TAFS FOR KOMA...KLNK...KOFK.

LOW CLOUDS AND FOG WILL BE THE MAIN CONCERNS AT LEAST THROUGH THE
MORNING HOURS. LIFR CONDITIONS SHOULD CONTINUE AT KOMA THROUGH AT
LEAST MID MORNING BUT SLOWLY IMPROVE TO VFR BY MID/LATE AFTERNOON.
FARTHER WEST AT KLNK AND KOFK...THE FOG WILL BE MORE VARIABLE THIS
MORNING. 13 KM RUC MODEL AND HIGH RESOLUTION RAPID REFRESH MODEL
BOTH SEEMED TO HAVE SOMEWHAT OF A HANDLE ON THE LOW CLOUDS.

WEST/SOUTHWEST WINDS SHOULD ALLOW FOR MAINLY VFR CONDITIONS FROM
MID AFTERNOON INTO THE EVENING WITH WEST OR SOUTHWEST LOW LEVEL
WINDS. IFR VSBYS COULD REFORM THIS EVENING FOR A WHILE...BUT DID
NOT MENTION AT THIS TIME. OTHERWISE...A COLD FRONT WILL PUSH
SOUTHWARD ACROSS THE AREA TONIGHT...SHIFTING WINDS TO THE NORTH.
LOOK FOR MVFR CEILINGS TO DEVELOP BEHIND THE FRONT. THERE COULD
ALSO BE SOME LIGHT SNOW OR FREEZING DRIZZLE.

MILLER

PREV DISCUSSION... /ISSUED 308 AM CST MON FEB 6 2012/

DISCUSSION...

MAIN FORECAST CHALLENGE WILL BE EXTENT OF STRATUS/FOG AND HOW MUCH
THIS CAN ERODE THROUGH THE DAY. FOCUS THEN SHIFTS TO INCOMING
COLD FRONT AND SMALL CHANCE OF PCPN TONIGHT INTO TUESDAY.

UPPER CLOSED LOW CURRENTLY OVER THE GREAT BASIN WILL OPEN AND
CONTINUE TO PUSH EAST TOWARD THE CENTRAL PLAINS TODAY WHILE A
SHORTWAVE TROF OVER SRN CANADA MOVES SOUTH INTO THE NRN PLAINS
TONIGHT. AT THE SFC...AREA OF HIGH PRESSURE IS CENTERED OVER THE
SOUTHERN PLAINS WITH CALM WINDS OVER THE ENTIRE CWA. DENSE FOG
FORMED EARLY LAST EVENING OVER SNOWPACK AND DO EXPECT FOG TO LIFT
BY MID-LATE MORNING. STRATUS DECK OVER THE EASTERN COUNTIES IS
EXPECTED TO HANG ON THRU MUCH OF THE MORNING AND PERHAPS EVEN
INTO THE AFTERNOON HOURS AS INDICATED BY LATEST HRRR MODEL RUNS.
WL EXTEND DENSE FOG ADVISORY UNTIL 16Z AS VISIBILITIES WL BE SLOW
TO IMPROVE. STRATUS IN ADDITION TO SNOWCOVER WL PLAY HAVOC ON HIGH
TEMPERATURES. HAVE FORECAST HIGHS NEAR OR JUST ABOVE FREEZING
TODAY.

CDFNT ASSOCIATED WITH SRN CANADIAN SHORTWAVE WL MOVE INTO THE REGION
EARLY THIS EVENING AS WEAKENING SHORTWAVE ENERGY FROM GREAT BASIN
LOW APPROACHES THE AREA. LIGHT PCPN STILL ON TRACK TO DEVELOP ACROSS
KS/MO AND INTO SERN NEB. FORECAST SOUNDINGS INDICATE THE POTENTIAL
FOR LIGHT FREEZING DRIZZLE INTITIALLY AND THEN A QUICK CHANGE TO
LIGHT SNOW IF NOT JUST FLURRIES. PERIOD OF FORCING IS BRIEF AND
ONLY EXPECT LIGHT SNOWFALL ACCUMULATIONS OF GENERALLY A TENTH OF
AN INCH OR SO LATE TONIGHT INTO TUESDAY MORNING.

DRY WEATHER IS EXPECTED THEREAFTER AS SFC HIGH PRESSURE MOVES
OVER THE REGION ON WEDNESDAY. A STRONG COLD FRONT WILL SURGE SOUTH
THROUGH THE AREA LATE THURSDAY. HAVE COOLED TEMPS SIGNIFICANTLY
OVER THE WEEKEND TO ACCOUNT FOR THIS SURGE OF COLD AIR.

KERN

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR IAZ043-055-056-069-
     079-080-090-091.

&&

$$




AREA FORECAST DISCUSSION

NWS OMAHA/VALLEY NE

 733 AM CST MON FEB 6 2012

.UPDATE...

TAKING A LOOK AT LATEST OBSERVATIONS AND WEB CAMS...DENSE FOG IS
NOT PREVALENT IN OUR WESTERN COUNTIES. DENSE FOG ADVISORIES WEST
OF OUR AREA WERE CANCELLED EARLIER...SO WILL GO AHEAD AND CLEAR
WESTERN PARTS OF THE DENSE FOG ADVISORY. THE KOAX 12Z SOUNDING
SHOWED WEST OR SOUTHWEST WINDS OF 10-14 KNOTS JUST OFF THE SURFACE
SO THIS SHOULD HELP WITH THE FOG. WILL KEEP ADVISORY UNTIL 16Z FOR
EXTREME EASTERN NEBRASKA AND SOUTHWEST IOWA....

MILLER

&&

.PREV DISCUSSION... /ISSUED 520 AM CST MON FEB 6 2012/

AVIATION...
12Z TAFS FOR KOMA...KLNK...KOFK.

LOW CLOUDS AND FOG WILL BE THE MAIN CONCERNS AT LEAST THROUGH THE
MORNING HOURS. LIFR CONDITIONS SHOULD CONTINUE AT KOMA THROUGH AT
LEAST MID MORNING BUT SLOWLY IMPROVE TO VFR BY MID/LATE AFTERNOON.
FARTHER WEST AT KLNK AND KOFK...THE FOG WILL BE MORE VARIABLE THIS
MORNING. 13 KM RUC MODEL AND HIGH RESOLUTION RAPID REFRESH MODEL
BOTH SEEMED TO HAVE SOMEWHAT OF A HANDLE ON THE LOW CLOUDS.

WEST/SOUTHWEST WINDS SHOULD ALLOW FOR MAINLY VFR CONDITIONS FROM
MID AFTERNOON INTO THE EVENING WITH WEST OR SOUTHWEST LOW LEVEL
WINDS. IFR VSBYS COULD REFORM THIS EVENING FOR A WHILE...BUT DID
NOT MENTION AT THIS TIME. OTHERWISE...A COLD FRONT WILL PUSH
SOUTHWARD ACROSS THE AREA TONIGHT...SHIFTING WINDS TO THE NORTH.
LOOK FOR MVFR CEILINGS TO DEVELOP BEHIND THE FRONT. THERE COULD
ALSO BE SOME LIGHT SNOW OR FREEZING DRIZZLE.

MILLER

PREV DISCUSSION... /ISSUED 308 AM CST MON FEB 6 2012/

DISCUSSION...

MAIN FORECAST CHALLENGE WILL BE EXTENT OF STRATUS/FOG AND HOW MUCH
THIS CAN ERODE THROUGH THE DAY. FOCUS THEN SHIFTS TO INCOMING
COLD FRONT AND SMALL CHANCE OF PCPN TONIGHT INTO TUESDAY.

UPPER CLOSED LOW CURRENTLY OVER THE GREAT BASIN WILL OPEN AND
CONTINUE TO PUSH EAST TOWARD THE CENTRAL PLAINS TODAY WHILE A
SHORTWAVE TROF OVER SRN CANADA MOVES SOUTH INTO THE NRN PLAINS
TONIGHT. AT THE SFC...AREA OF HIGH PRESSURE IS CENTERED OVER THE
SOUTHERN PLAINS WITH CALM WINDS OVER THE ENTIRE CWA. DENSE FOG
FORMED EARLY LAST EVENING OVER SNOWPACK AND DO EXPECT FOG TO LIFT
BY MID-LATE MORNING. STRATUS DECK OVER THE EASTERN COUNTIES IS
EXPECTED TO HANG ON THRU MUCH OF THE MORNING AND PERHAPS EVEN
INTO THE AFTERNOON HOURS AS INDICATED BY LATEST HRRR MODEL RUNS.
WL EXTEND DENSE FOG ADVISORY UNTIL 16Z AS VISIBILITIES WL BE SLOW
TO IMPROVE. STRATUS IN ADDITION TO SNOWCOVER WL PLAY HAVOC ON HIGH
TEMPERATURES. HAVE FORECAST HIGHS NEAR OR JUST ABOVE FREEZING
TODAY.

CDFNT ASSOCIATED WITH SRN CANADIAN SHORTWAVE WL MOVE INTO THE REGION
EARLY THIS EVENING AS WEAKENING SHORTWAVE ENERGY FROM GREAT BASIN
LOW APPROACHES THE AREA. LIGHT PCPN STILL ON TRACK TO DEVELOP ACROSS
KS/MO AND INTO SERN NEB. FORECAST SOUNDINGS INDICATE THE POTENTIAL
FOR LIGHT FREEZING DRIZZLE INTITIALLY AND THEN A QUICK CHANGE TO
LIGHT SNOW IF NOT JUST FLURRIES. PERIOD OF FORCING IS BRIEF AND
ONLY EXPECT LIGHT SNOWFALL ACCUMULATIONS OF GENERALLY A TENTH OF
AN INCH OR SO LATE TONIGHT INTO TUESDAY MORNING.

DRY WEATHER IS EXPECTED THEREAFTER AS SFC HIGH PRESSURE MOVES
OVER THE REGION ON WEDNESDAY. A STRONG COLD FRONT WILL SURGE SOUTH
THROUGH THE AREA LATE THURSDAY. HAVE COOLED TEMPS SIGNIFICANTLY
OVER THE WEEKEND TO ACCOUNT FOR THIS SURGE OF COLD AIR.

KERN

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR NEZ015-034-
     045-052-053-067-068-090>093.

IA...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR IAZ043-055-
     056-069-079-080-090-091.

&&

$$




AREA FORECAST DISCUSSION

NWS OMAHA/VALLEY NE

 308 AM CST MON FEB 6 2012

.DISCUSSION...

MAIN FORECAST CHALLENGE WILL BE EXTENT OF STRATUS/FOG AND HOW MUCH THIS
CAN ERODE THROUGH THE DAY. FOCUS THEN SHIFTS TO INCOMING COLD
FRONT AND SMALL CHANCE OF PCPN TONIGHT INTO TUESDAY.

UPPER CLOSED LOW CURRENTLY OVER THE GREAT BASIN WILL OPEN AND
CONTINUE TO PUSH EAST TOWARD THE CENTRAL PLAINS TODAY WHILE A
SHORTWAVE TROF OVER SRN CANADA MOVES SOUTH INTO THE NRN PLAINS
TONIGHT. AT THE SFC...AREA OF HIGH PRESSURE IS CENTERED OVER THE
SOUTHERN PLAINS WITH CALM WINDS OVER THE ENTIRE CWA. DENSE FOG
FORMED EARLY LAST EVENING OVER SNOWPACK AND DO EXPECT FOG TO LIFT
BY MID-LATE MORNING. STRATUS DECK OVER THE EASTERN COUNTIES IS
EXPECTED TO HANG ON IN THRU MUCH OF THE MORNING AND PERHAPS EVEN
INTO THE AFTERNOON HOURS AS INDICATED BY LATEST HRRR MODEL RUNS.
WL EXTEND DENSE FOG ADVISORY UNTIL 16Z AS VISIBILITIES WL BE SLOW
TO IMPROVE. STRATUS IN ADDITION TO SNOWCOVER WL PLAY HAVOC ON
HIGH TEMPERATURES. HAVE FORECAST HIGHS NEAR OR JUST ABOVE
FREEZING TODAY.

CDFNT ASSOCIATED WITH SRN CANADIAN SHORTWAVE WL MOVE INTO THE REGION
EARLY THIS EVENING AS WEAKENING SHORTWAVE ENERGY FROM GREAT BASIN
LOW APPROACHES THE AREA. LIGHT PCPN STILL ON TRACK TO DEVELOP ACROSS
KS/MO AND INTO SERN NEB. FORECAST SOUNDINGS INDICATE THE POTENTIAL
FOR LIGHT FREEZING DRIZZLE INTITIALLY AND THEN A QUICK CHANGE TO
LIGHT SNOW IF NOT JUST FLURRIES. PERIOD OF FORCING IS BRIEF AND
ONLY EXPECT LIGHT SNOWFALL ACCUMULATIONS OF GENERALLY A TENTH OF
AN INCH OR SO LATE TONIGHT INTO TUESDAY MORNING.

DRY WEATHER IS EXPECTED THEREAFTER AS SFC HIGH PRESSURE MOVES
OVER THE REGION ON WEDNESDAY. A STRONG COLD FRONT WILL SURGE SOUTH
THROUGH THE AREA LATE THURSDAY. HAVE COOLED TEMPS SIGNIFICANTLY
OVER THE WEEKEND TO ACCOUNT FOR THIS SURGE OF COLD AIR.

KERN

&&

.AVIATION...

06Z TAFS FOR KOFK...KOMA AND KLNK.

AS EXPECTED FOG HAS DEVELOPED AT ALL TAF SITES THIS EVNG. THESE LIFR
CONDS SHOULD CONT THROUGH A GOOD PART OF THE NIGHT AT ALL 3 SITES.
SOME IMPROVEMENT IN VISBY IS EXPECTED DURING THE MRNG BUT AT LNK/OMA
THE LIFR CIGS ARE LIKELY TO CONT THROUGH AT LEAST THE MRNG AND MAY
TRY TO CONT INTO THE AFTN. AT OFK THE LOW LEVEL FLOW FM THE WEST
WILL LIKELY ALLOW FOR THE LOW STUFF TO MOV OUT BY MID TO LATE MRNG
AS THEY ARE EXPECTED TO BE ON THE EDGE OF THE WWD EXTENT OF THE
CLOUDS. IF THE LOW CLOUDS DO EXIT OMA/LNK TMRW AFTN WE MAY ONCE
AGAIN SEE SOME FG DVLP MON EVNG AHEAD OF A COLD FRONT THAT WILL MOV
THRU LATE IN THE EVNG CLEANING OUT THE LOW LEVEL MOISTURE AND
TURNING THE WINDS TO THE N.

BOUSTEAD

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR NEZ012-015-
     017-018-030>034-042>045-050>053-065>068-078-088>093.

IA...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR IAZ043-055-
     056-069-079-080-090-091.

&&

$$




AREA FORECAST DISCUSSION

NWS OMAHA/VALLEY NE

 1141 PM CST SUN FEB 5 2012

.AVIATION...
06Z TAFS FOR KOFK...KOMA AND KLNK.

AS EXPECTED FOG HAS DEVELOPED AT ALL TAF SITES THIS EVNG. THESE LIFR
CONDS SHOULD CONT THROUGH A GOOD PART OF THE NIGHT AT ALL 3 SITES.
SOME IMPROVEMENT IN VISBY IS EXPECTED DURING THE MRNG BUT AT LNK/OMA
THE LIFR CIGS ARE LIKELY TO CONT THROUGH AT LEAST THE MRNG AND MAY
TRY TO CONT INTO THE AFTN. AT OFK THE LOW LEVEL FLOW FM THE WEST
WILL LIKELY ALLOW FOR THE LOW STUFF TO MOV OUT BY MID TO LATE MRNG
AS THEY ARE EXPECTED TO BE ON THE EDGE OF THE WWD EXTENT OF THE
CLOUDS. IF THE LOW CLOUDS DO EXIT OMA/LNK TMRW AFTN WE MAY ONCE
AGAIN SEE SOME FG DVLP MON EVNG AHEAD OF A COLD FRONT THAT WILL MOV
THRU LATE IN THE EVNG CLEANING OUT THE LOW LEVEL MOISTURE AND
TURNING THE WINDS TO THE N.

BOUSTEAD

&&

.UPDATE...

UPDATED TO ADD DENSE FOG ADVISORY.

&&

.DISCUSSION...

THE STRATUS DECK IS SLOWLY MAKING WWD PROGRESS ACROSS THE CTNRL
PART OF THE CWA. THE OPERATIONAL MODELS CONT TO STRUGGLE WITH THIS
NEAR GROUND LAYER DECK. ON THE WESTERN EDGE OF THIS DECK THE
TEMPERATURES FELL RAPIDLY THIS EVENING AND ALLOW FOR DENSE FOG TO
DVLP WITH ALL THE LOW LEVEL MOISTURE AROUND AND LIGHT WINDS. WOULD
EXPECT THE DECK TO CONT TO MAKE VERY SLOW PROGRESS TO THE WEST
OVERNIGHT...ESPECIALLY IN SE NEB WHERE THE WINDS JUST OFF THE SFC
ARE WEAKER THAN IN NE NEB. OTHERWISE THE DENSE FOG SHOULD BE
FAIRLY WIDESPREAD OVERNIGHT. LATE TONIGHT THE LOW LEVEL GRADIENT
STARTS TO INCREASE A LITTLE AND BY MON MRNG THIS SHOULD START TO
MOV THE STRATUS BACK EWD.

BOUSTEAD

&&

SHORT TERM...TONIGHT THROUGH WEDNESDAY
A LULL IN WEATHER ACTIVITY WILL KEEP THE AREA QUIET THROUGH
TOMORROW.  SUBJECTIVE 12Z UPPER AIR ANALYSIS INDICATES UPPER LOW
CUTTING OFF OVER THE GREAT BASIN FROM AN ELONGATED EAST-WEST TROUGH
AXIS...WITH AN UPPER HIGH CENTERED AROUND SOUTHERN AB/SASK/MB.
STRONG UPPER-LEVEL SHORTWAVE WAS DESCENDING OUT OF THE NW
TERRITORIES INTO NORTHERN AB/SASK.  COLD AIR REMAINS LOCKED WELL
NORTH AND EAST OF THE CENTRAL US...WITH AN 850MB COLD POOL CENTERED
OVER KS/OK UNDER THE UPPER TROUGH...AND A WARM POOL OVER
SASK/MB/ND/MT UNDER THE UPPER HIGH THAT WAS DROPPING INTO THE
CENTRAL US.

MAIN FORECAST CONCERNS INCLUDE STRATUS/FOG THROUGH TONIGHT...AND
LIGHT SNOW POTENTIAL ON TUESDAY.  MODELS ARE NOT HANDLING THE
SHALLOW STRATUS DECK WELL...BUT HRRR DOES HAVE A GOOD HANDLE ON THE
CURRENT EXTENT OF THE STRATUS AND FOG...AND RUC IS IN THE BALLPARK.
BOTH KEEP THE STRATUS LOCKED IN ROUGHLY ALONG AND EAST OF THE
MISSOURI RIVER THROUGH THE NIGHT...ALONG WITH DEVELOPING/KEEPING FOG
IN ROUGHLY THOSE AREAS OVERNIGHT.  GIVEN AMPLE LOW-LEVEL
MOISTURE...LACK OF ANY KIND OF COLD AIR PUSH OR ADVECTION THAT WOULD
SCOUR THE MOISTURE...AND PERSISTENCE THROUGH THE DAY...AM INCLINED
TO LEAN PESSIMISTIC AND KEEP THE FOG/STRATUS OVERNIGHT.  HAVE
INCLUDED A RATHER SHARP GRADIENT FROM OVERCAST TO CLEAR...WITH SOME
WESTWARD EXPANSION THROUGH THE NIGHT.  NATURALLY...TEMPERATURES WILL
DEPEND STRONGLY ON LOCATION OF CLOUDS.  FOR NOW...HAVE KEPT AREAS
WEST OF A LINE FROM AROUND LINCOLN TO WAYNE CLEAR...AND THUS MUCH
COLDER...THAN AREAS EAST.

DID ALLOW FOR CLOUDS TO SCOUR OUT IN THE MORNING HOURS TOMORROW AS
WEST WINDS INCREASE A BIT...THOUGH CONFIDENCE IS LOW IN THE TIMING
OF THIS.  SHOULD SEE SOME MODERATION WITH WARM AIR ADVECTION AND
LIGHT MIXING DURING THE DAY...THOUGH INCREASING HIGH-LEVEL CLOUDS
LATER IN THE DAY MAY HINDER FULL SUNSHINE.  COLD FRONT ASSOCIATED
WITH THE SHORTWAVE CURRENTLY LOCATED IN NORTHERN CANADA WILL DROP
THROUGH ON MONDAY NIGHT.  NORTHERN STREAM WAVE AND SOUTHERN STREAM
WEAKENING/EJECTING UPPER LOW ARE PROGGED TO PHASE AS THE TWO
INTERACT OVER THE CENTRAL PLAINS...AND THE RESULTING UPPER-LEVEL
TROUGH WILL GENERATE AN AREA OF PRECIPITATION OVER KS/MO BEGINNING
LATE MONDAY NIGHT.  SOUTHERN CWA LIKELY WILL BE JUST ON THE NORTHERN
FRINGE OF THAT PRECIPITATION...WITH SOME LIGHT SNOW SKIMMING THE
AREA MAINLY ON MONDAY.  HAVE BACKED OFF MONDAY NIGHT PRECIP MENTION
AS SYSTEM WILL STILL BE WELL WEST AND JUST GETTING ITS ACT
TOGETHER...AND INCREASED TO HIGHER CHANCES ON TUESDAY IN THE
SOUTHERNMOST CWA WHILE TRIMMING POPS IN AREAS NORTH OF I-80 AS DRY
AIR WILL FEED INTO THE NORTHERN CWA AND SUPPRESS NORTHWARD EXPANSION
OF PRECIP.

HIGH PRESSURE WILL DROP INTO THE AREA ON TUESDAY NIGHT AS THE SYSTEM
CLEARS AWAY TO THE SOUTHEAST...AND EXPECT TEMPERATURES WILL BE ABLE
TO FALL QUITE A BIT...ESPECIALLY OVER SNOWY AREAS. HAVE SHAVED A FEW
DEGREES OFF TEMPS ON TUESDAY NIGHT...AND HAVE INCLUDED AN AREA OF
COLDER TEMPERATURES OVER THE SNOWPACK ON WEDNESDAY.

MAYES

LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
STILL DRY THROUGH THE PERIOD WITH NO MAJOR WEATHER SYSTEMS OF NOTE
WITH GOOD MODEL AGREEMENT THROUGH FRIDAY. A COLD FRONT DOES MOVE
THROUGH THE REGION ON THURSDAY BRINGING SOME SLIGHTLY COOLER AIR FOR
FRIDAY. MOISTURE IS VERY MEAGER THOUGH...THUS DID NOT ADD ANY
MENTION OF PRECIP AT THIS TIME. MODEL CONTINUITY BEYOND FRIDAY
REMAINS VERY LOW. THE ECMWF BUILDS A RIDGE ACROSS THE CENTRAL US
WITH SUBSTANTIAL WARMING...WHILE THE GFS ALLOWS ANOTHER COLDER SURGE
OF AIR TO MOVE SOUTHWARD SATURDAY AND DOESN/T BEGIN A SLIGHT
WARMUP UNTIL SUNDAY. UNTIL MORE CONTINUITY DEVELOPS...WILL TREND
GRIDS SATURDAY AND SUNDAY TOWARD CLIMATOLOGY/HPC/BLENDED
SOLUTIONS.

DEWALD

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 9 AM CST MONDAY FOR NEZ015-017-018-
     030>034-042>045-050>053-065>068-078-088>093.

IA...DENSE FOG ADVISORY UNTIL 9 AM CST MONDAY FOR IAZ043-055-056-069-
     079-080-090-091.

&&

$$




AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

 634 AM EST MON FEB 6 2012

.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN PARKED JUST SOUTH OF
PENNSYLVANIA TODAY AND TUESDAY. A COLD FRONT WILL SAG SOUTH ACROSS
THE STATE TUESDAY NIGHT. A WEAK WAVE ON THE FRONT WILL THEN PASS
SOUTH OF THE REGION ON WEDNESDAY. A MORE SIGNIFICANT COLD FRONT
WILL LIKELY PUSH THROUGH THE REGION LATE FRIDAY...POTENTIALLY
DELIVERING A BRIEF SHOT OF ARCTIC AIR.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CLEAR SKIES AND A CALM WIND ASSOC WITH SFC RIDGE HAS ALLOWED SOME
RADIATION FOG TO FORM ALONG THE MASON DIXON LINE. LATEST HRRR SFC
RH FIELDS SUGGEST IT WILL DISSIPATE BY ARND 13Z. UPSTREAM SATL
IMAGERY INDICATES A NEARLY CLOUDLESS DAY IS ON TAP FOR CENTRAL PA.

INCREASING WLY TO SWRLY FLOW AHEAD OF AN APPROACHING COLD FRONT TO
THE NORTH WILL DRAW A SURGE OF VERY MILD AIR INTO THE REGION
TODAY. UNDER SUNNY SKIES...TEMPS SHOULD REACH 45-50F OVER MOST OF
CENTRAL PA. BUFKIT SOUNDINGS INDICATE SWRLY WIND GUSTS ARND 20KTS
OVR THE NORTH BY AFTN...WITH A LIGHTER BREEZE OVR SOUTHERN PA.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
PREFRONTAL AIR MASS WILL REMAIN MILD TONIGHT...BUT MCLEAR SKIES
AND A DIMINISHING BREEZE SHOULD ALLOW TEMPS TO FALL BACK TO THE
M/U20S IN MOST LOCATIONS. APPROACH OF COLD FRONT COULD BRING
INCREASING CLOUDS TO THE N MTNS TOWARD DAWN. UPPER LVL SHORTWAVE
LIFTING EAST FROM THE OHIO VALLEY WILL TRACK ALONG THE MASON DIXON
LINE TONIGHT. HOWEVER...ALL MDL DATA INDICATING NOT ENOUGH
MOISTURE PRESENT TO EVEN PRODUCE CLOUDINESS ACROSS SOUTHERN PA.

COLD FRONT WILL SAG SLOWLY SOUTHWARD ACROSS THE STATE ON TUESDAY.
HOWEVER...LACK OF SIG LG SCALE FORCING OR MOISTURE WILL RESULT IN A
DRY FROPA FOR MOST OF THE AREA. STRATO-CU AND SCT FLURRIES ARE
LIKELY TO FOLLOW THE FRONTAL PASSAGE ACROSS THE NORTH...WHILE
SOUTHERN PA SQUEAKS OUT ANOTHER MSUNNY AND MILD DAY. MAX TEMPS
SHOULD RANGE FROM THE M30S N MTNS...TO U40S LOWER SUSQ VALLEY.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
AS COLD FRONT SAGS SOUTH OF THE MASON DIXON LINE WED...MDLS TRACK
SHORTWAVE AND ASSOC WEAK SFC WAVE SOUTH OF PA. DESPITE LIMITED
MOISTURE...MDL DATA INDICATES THIS WILL BE A FAIRLY VIGOROUS
SHORTWAVE WITH THE POTENTIAL TO PRODUCE A PERIOD OF LGT SNOW
WEDNESDAY. TIMING OF SHORTWAVE UNCERTAIN...WITH GFS/GEFS FASTER
THAN ECMWF. HOWEVER...HAVE INCREASED POPS IN THE 06Z WED-06Z THU
TIME FRAME ACROSS ALL OF CENTRAL/SOUTHERN PA. THE LAUREL HIGHLANDS
APPEAR MOST LIKELY TO RECEIVE A COUPLE INCHES OF SNOW FROM THIS
SYSTEM...DUE TO OROGRAPHIC ENHANCEMENT. FURTHER EAST...RELATIVELY
MILD SFC TEMPS WILL BE A LIMITING FACTOR FOR ANY ACCUMS ACROSS THE
LOWER SUSQ VALLEY...ESP DURING THE DAYLIGHT HRS.

SUNNY AND MILD WX APPEARS LIKELY TO RETURN THURSDAY...AS RIDGE OF
HIGH PRESSURE BUILDS OVR THE REGION. FCST UNCERTAINTY RAMPS UP A
BIT BY FRI/SAT...AS MDL SPREAD INCREASES WITH RESPECT TO
STRENGTH/TIMING OF NEXT SHORTWAVE. A BLEND OF GEFS AND EC
ENSEMBLES POINTS TOWARD A MAINLY DRY COLD FRONT PASSAGE FRI NIGHT...FOLLOWED
BY A SEASONABLY COLD/DRY WEEKEND. A COUPLE STRONGER/SLOWER GEFS
MEMBERS...WITH POSSIBLE E COAST CYCLOGENESIS...REMAIN UNLIKELY
OUTLIERS ATTM.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
A RIDGE OF HIGH PRESSURE WILL DOMINATE THE WEATHER ACROSS CENTRAL
PENNSYLVANIA TODAY AND TUESDAY. A COLD FRONT WILL SAG SOUTH ACROSS
THE STATE TUESDAY NIGHT.

BRIEF BOUT OF MVFR CIGS AT KBFD-KIPT EARLY ALONG PERIPHERY OF
BUILDING RIDGE...ALONG WITH SCT MVFR VSBY IN THE SE EARLY THIS
MORNING. BUT CONDITIONS IMPROVE QUICKLY...LEAVING A NEARLY
CLOUDLESS VFR DAY FROM LATE MORNING INTO TONIGHT. WINDS TODAY WILL
INCREASE FROM THE SW...SUSTAINED AT AROUND 10 MPH WITH GUSTS TO 20
MPH...AHEAD OF AN APPROACHING COLD FRONT. THE FRONT SLIPS INTO
NORTHERN PA LATE TONIGHT...LIKELY BRINGING MVFR CIGS INTO KBFD
AFTER 06Z TUE.

OUTLOOK...
TUE...MVFR POSS NW HALF. VFR SE.
WED...MVFR POSS WITH SHSN.
THU-FRI...VFR.

&&

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

&&

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







AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

 601 AM EST MON FEB 6 2012

.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN PARKED JUST SOUTH OF
PENNSYLVANIA TODAY AND TUESDAY. A COLD FRONT WILL SAG SOUTH ACROSS
THE STATE TUESDAY NIGHT. A WEAK WAVE ON THE FRONT WILL THEN PASS
SOUTH OF THE REGION ON WEDNESDAY. A MORE SIGNIFICANT COLD FRONT
WILL LIKELY PUSH THROUGH THE REGION LATE FRIDAY...POTENTIALLY
DELIVERING A BRIEF SHOT OF ARCTIC AIR.

&&

.NEAR TERM /UNTIL 7 AM THIS MORNING/...
CLEAR SKIES AND A CALM WIND ASSOC WITH SFC RIDGE HAS ALLOWED SOME
RADIATION FOG TO FORM ALONG THE MASON DIXON LINE. LATEST HRRR SFC
RH FIELDS SUGGEST IT WILL DISSIPATE BY ARND 13Z. UPSTREAM SATL
IMAGERY INDICATES A NEARLY CLOUDLESS DAY IS ON TAP FOR CENTRAL PA.

INCREASING WLY TO SWRLY FLOW AHEAD OF AN APPROACHING COLD FRONT TO
THE NORTH WILL DRAW A SURGE OF VERY MILD AIR INTO THE REGION
TODAY. UNDER SUNNY SKIES...TEMPS SHOULD REACH 45-50F OVER MOST OF
CENTRAL PA. BUFKIT SOUNDINGS INDICATE SWRLY WIND GUSTS ARND 20KTS
OVR THE NORTH BY AFTN...WITH A LIGHTER BREEZE OVR SOUTHERN PA.

&&

.SHORT TERM /7 AM THIS MORNING THROUGH 6 PM TUESDAY/...
PREFRONTAL AIR MASS WILL REMAIN MILD MONDAY NIGHT...BUT MCLEAR
SKIES AND A DIMINISHING BREEZE SHOULD ALLOW TEMPS TO FALL BACK TO
THE M/U20S IN MOST LOCATIONS. APPROACH OF COLD FRONT COULD BRING
INCREASING CLOUDS TO THE N MTNS TOWARD DAWN. UPPER LVL SHORTWAVE
LIFTING EAST FROM THE OHIO VALLEY WILL TRACK ALONG THE MASON DIXON
LINE TONIGHT. HOWEVER...ALL MDL DATA INDICATING NOT ENOUGH
MOISTURE PRESENT TO EVEN PRODUCE CLOUDINESS ACROSS SOUTHERN PA.

COLD FRONT WILL SAG SLOWLY SOUTHWARD ACROSS THE STATE ON TUESDAY.
HOWEVER...LACK OF SIG LG SCALE FORCING OR MOISTURE WILL RESULT IN A
DRY FROPA FOR MOST OF THE AREA. STRATO-CU AND SCT FLURRIES ARE
LIKELY TO FOLLOW THE FRONTAL PASSAGE ACROSS THE NORTH...WHILE
SOUTHERN PA SQUEAKS OUT ANOTHER MSUNNY AND MILD DAY. MAX TEMPS
SHOULD RANGE FROM THE M30S N MTNS...TO U40S LOWER SUSQ VALLEY.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
AS COLD FRONT SAGS SOUTH OF THE MASON DIXON LINE WED...MDLS TRACK
SHORTWAVE AND ASSOC WEAK SFC WAVE SOUTH OF PA. DESPITE LIMITED
MOISTURE...MDL DATA INDICATES THIS WILL BE A FAIRLY VIGOROUS
SHORTWAVE WITH THE POTENTIAL TO PRODUCE A PERIOD OF LGT SNOW
WEDNESDAY. TIMING OF SHORTWAVE UNCERTAIN...WITH GFS/GEFS FASTER
THAN ECMWF. HOWEVER...HAVE INCREASED POPS IN THE 06Z WED-06Z THU
TIME FRAME ACROSS ALL OF CENTRAL/SOUTHERN PA. THE LAUREL HIGHLANDS
APPEAR MOST LIKELY TO RECEIVE A COUPLE INCHES OF SNOW FROM THIS
SYSTEM...DUE TO OROGRAPHIC ENHANCEMENT. FURTHER EAST...RELATIVELY
MILD SFC TEMPS WILL BE A LIMITING FACTOR FOR ANY ACCUMS ACROSS THE
LOWER SUSQ VALLEY...ESP DURING THE DAYLIGHT HRS.

SUNNY AND MILD WX APPEARS LIKELY TO RETURN THURSDAY...AS RIDGE OF
HIGH PRESSURE BUILDS OVR THE REGION. FCST UNCERTAINTY RAMPS UP A
BIT BY FRI/SAT...AS MDL SPREAD INCREASES WITH RESPECT TO
STRENGTH/TIMING OF NEXT SHORTWAVE. A BLEND OF GEFS AND EC
ENSEMBLES POINTS TOWARD A MAINLY DRY COLD FRONT PASSAGE FRI NIGHT...FOLLOWED
BY A SEASONABLY COLD/DRY WEEKEND. A COUPLE STRONGER/SLOWER GEFS
MEMBERS...WITH POSSIBLE E COAST CYCLOGENESIS...REMAIN UNLIKELY
OUTLIERS ATTM.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
A RIDGE OF HIGH PRESSURE WILL DOMINATE THE WEATHER ACROSS CENTRAL
PENNSYLVANIA TODAY AND TUESDAY. A COLD FRONT WILL SAG SOUTH ACROSS
THE STATE TUESDAY NIGHT.

BRIEF BOUT OF MVFR CIGS AT KBFD-KIPT EARLY ALONG PERIPHERY OF
BUILDING RIDGE...ALONG WITH SCT MVFR VSBY IN THE SE EARLY THIS
MORNING. BUT CONDITIONS IMPROVE QUICKLY...LEAVING A NEARLY
CLOUDLESS VFR DAY FROM LATE MORNING INTO TONIGHT. WINDS TODAY WILL
INCREASE FROM THE SW...SUSTAINED AT AROUND 10 MPH WITH GUSTS TO 20
MPH...AHEAD OF AN APPROACHING COLD FRONT. THE FRONT SLIPS INTO
NORTHERN PA LATE TONIGHT...LIKELY BRINGING MVFR CIGS INTO KBFD
AFTER 06Z TUE.

OUTLOOK...
TUE...MVFR POSS NW HALF. VFR SE.
WED...MVFR POSS WITH SHSN.
THU-FRI...VFR.

&&

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

&&

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







AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

 536 AM EST MON FEB 6 2012

.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN PARKED JUST SOUTH OF
PENNSYLVANIA TODAY AND TUESDAY. A COLD FRONT WILL SAG SOUTH ACROSS
THE STATE TUESDAY NIGHT. A WEAK WAVE ON THE FRONT WILL THEN PASS
SOUTH OF THE REGION ON WEDNESDAY. A MORE SIGNIFICANT COLD FRONT
WILL LIKELY PUSH THROUGH THE REGION LATE FRIDAY...POTENTIALLY
DELIVERING A BRIEF SHOT OF ARCTIC AIR.

&&

.NEAR TERM /UNTIL 7 AM THIS MORNING/...
CLEAR SKIES AND A CALM WIND ASSOC WITH SFC RIDGE HAS ALLOWED SOME
RADIATION FOG TO FORM ALONG THE MASON DIXON LINE. LATEST HRRR SFC
RH FIELDS SUGGEST IT WILL DISSIPATE BY ARND 13Z. UPSTREAM SATL
IMAGERY INDICATES A NEARLY CLOUDLESS DAY IS ON TAP FOR CENTRAL PA.

INCREASING WLY TO SWRLY FLOW AHEAD OF AN APPROACHING COLD FRONT TO
THE NORTH WILL DRAW A SURGE OF VERY MILD AIR INTO THE REGION
TODAY. UNDER SUNNY SKIES...TEMPS SHOULD REACH 45-50F OVER MOST OF
CENTRAL PA. BUFKIT SOUNDINGS INDICATE SWRLY WIND GUSTS ARND 20KTS
OVR THE NORTH BY AFTN...WITH A LIGHTER BREEZE OVR SOUTHERN PA.

&&

.SHORT TERM /7 AM THIS MORNING THROUGH 6 PM TUESDAY/...
PREFRONTAL AIR MASS WILL REMAIN MILD MONDAY NIGHT...BUT MCLEAR
SKIES AND A DIMINISHING BREEZE SHOULD ALLOW TEMPS TO FALL BACK TO
THE M/U20S IN MOST LOCATIONS. APPROACH OF COLD FRONT COULD BRING
INCREASING CLOUDS TO THE N MTNS TOWARD DAWN. UPPER LVL SHORTWAVE
LIFTING EAST FROM THE OHIO VALLEY WILL TRACK ALONG THE MASON DIXON
LINE TONIGHT. HOWEVER...ALL MDL DATA INDICATING NOT ENOUGH
MOISTURE PRESENT TO EVEN PRODUCE CLOUDINESS ACROSS SOUTHERN PA.

COLD FRONT WILL SAG SLOWLY SOUTHWARD ACROSS THE STATE ON TUESDAY.
HOWEVER...LACK OF SIG LG SCALE FORCING OR MOISTURE WILL RESULT IN A
DRY FROPA FOR MOST OF THE AREA. STRATO-CU AND SCT FLURRIES ARE
LIKELY TO FOLLOW THE FRONTAL PASSAGE ACROSS THE NORTH...WHILE
SOUTHERN PA SQUEAKS OUT ANOTHER MSUNNY AND MILD DAY. MAX TEMPS
SHOULD RANGE FROM THE M30S N MTNS...TO U40S LOWER SUSQ VALLEY.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
AS COLD FRONT SAGS SOUTH OF THE MASON DIXON LINE WED...MDLS TRACK
SHORTWAVE AND ASSOC WEAK SFC WAVE SOUTH OF PA. DESPITE LIMITED
MOISTURE...MDL DATA INDICATES THIS WILL BE A FAIRLY VIGOROUS
SHORTWAVE WITH THE POTENTIAL TO PRODUCE A PERIOD OF LGT SNOW
WEDNESDAY. TIMING OF SHORTWAVE UNCERTAIN...WITH GFS/GEFS FASTER
THAN ECMWF. HOWEVER...HAVE INCREASED POPS IN THE 06Z WED-06Z THU
TIME FRAME ACROSS ALL OF CENTRAL/SOUTHERN PA. THE LAUREL HIGHLANDS
APPEAR MOST LIKELY TO RECEIVE A COUPLE INCHES OF SNOW FROM THIS
SYSTEM...DUE TO OROGRAPHIC ENHANCEMENT. FURTHER EAST...RELATIVELY
MILD SFC TEMPS WILL BE A LIMITING FACTOR FOR ANY ACCUMS ACROSS THE
LOWER SUSQ VALLEY...ESP DURING THE DAYLIGHT HRS.

SUNNY AND MILD WX APPEARS LIKELY TO RETURN THURSDAY...AS RIDGE OF
HIGH PRESSURE BUILDS OVR THE REGION. FCST UNCERTAINTY RAMPS UP A
BIT BY FRI/SAT...AS MDL SPREAD INCREASES WITH RESPECT TO
STRENGTH/TIMING OF NEXT SHORTWAVE. A BLEND OF GEFS AND EC
ENSEMBLES POINTS TOWARD A MAINLY DRY COLD FRONT PASSAGE FRI NIGHT...FOLLOWED
BY A SEASONABLY COLD/DRY WEEKEND. A COUPLE STRONGER/SLOWER GEFS
MEMBERS...WITH POSSIBLE E COAST CYCLOGENESIS...REMAIN UNLIKELY
OUTLIERS ATTM.

&&

.AVIATION /10Z MONDAY THROUGH FRIDAY/...
A RIDGE OF HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS
PENNSYLVANIA. DRY AIR ADVECTION WILL ALLOW FOR VFR CIGS AND VSBYS
ACROSS THE REGION. THE ONLY CHANCE...ALBEIT LOW...FOR MVFR CIGS
WILL BE ALONG THE NY/PA BORDER AT BFD. ELSEWHERE VFR CONDITIONS
AND LIGHT WINDS WILL DOMINATE THROUGH MONDAY NIGHT.

OUTLOOK...
TUE...MVFR POSS NW HALF. VFR SE.
WED...MVFR POSS WITH SHSN.
THU-FRI...VFR.

&&

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

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD
AVIATION...CERU/RXR







AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

 116 AM EST MON FEB 6 2012

.SYNOPSIS...
A RIDGE OF HIGH PRESSURE OVER THE GREAT LAKES WILL BUILD
SOUTHEAST ACROSS PENNSYLVANIA ON MONDAY. A SERIES OF SHORTWAVES
WILL CARVE OUT A DEEPENING TROUGH ACROSS THE EASTERN CONUS BY
MID TO LATE WEEK.

&&

.NEAR TERM /UNTIL 7 AM THIS MORNING/...
CLEAR SKY AND A LIGHT WIND HAVE ALLOWED TEMPS TO FALL TO THE 20S
AS OF 06Z. AS SFC RIDGE DRIFTS SOUTH OF THE STATE...WIND MIGHT PICK UP A
BIT FROM THE WEST...CAUSING TEMPS TO LEVEL OFF DURING THE NEXT
COUPLE OF HOURS. BOTH LAMP GUIDANCE AND RUC SFC TEMPS INDICATE NO
MORE THAN A COUPLE DEG DROP IN TEMPS BTWN 06Z-12Z.

&&

.SHORT TERM /7 AM THIS MORNING THROUGH 6 PM TUESDAY/...
INCREASING WLY TO SWRLY FLOW AHEAD OF AN APPROACHING COLD FRONT TO
THE NORTH WILL DRAW A SURGE OF VERY MILD AIR INTO THE REGION
MONDAY. UNDER SUNNY SKIES...TEMPS SHOULD REACH 45-50F OVER MOST OF
CENTRAL PA. BUKKIT SOUNDINGS INDICATE SWRLY WIND GUSTS ARND 20KTS
BY AFTN...ESP ACROSS THE NW MTNS.

PREFRONTAL AIR MASS WILL REMAIN UNSEASONABLY MILD MONDAY NIGHT...
BUT WITH SLIGHT DECOUPLING MINS SHOULD STILL DROP BELOW FREEZING
IN MOST LOCATIONS. EXPECT MINS TUESDAY MORNING TO RANGE FROM THE
MID 20S IN THE NORTH TO AROUND 30 IN THE SOUTH.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
ALL MDL DATA INDICATING A WEAK COLD FRONT WILL SAG SOUTH ACROSS PA
ON TUESDAY...POSSIBLY ACCOMPANIED BY A FEW -SHSN OVR THE N MTNS.

AT THE SAME TIME...A SERIES OF FAST MOVING SYSTEMS MAY BRING
LIGHT SNOW AND SOME LIGHT RAIN TO THE AREA TUE INTO EARLY THU.

NOT A LOT OF CHANGE FROM YESTERDAY.

ANOTHER COLD FRONT DROPS SE LATE IN THE WEEK...BUT EXPECT THE
REAL COLD AIR TO STAY OVER EASTERN CANADA. WENT WITH A DRY
WEEKEND FOR NOW...AS EXPECT THE FRONT TO BE NORTH OF CENTRAL
PA.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
UPPER TROUGH IS MOVING
OFFSHORE AS WEAK FLOW DOMINATES THE REGION. DRY AIR ADVECTION WILL
ALLOW FOR VFR CIGS AND VSBYS ACROSS THE REGION. THE ONLY CHANCE
FOR MVFR CIGS WILL BE ALONG THE NY AND PA BORDER WITH A SLIGHT
POSSIBILITY ONCE THE REGION DECOUPLES AT BFD. ELSEWHERE VFR
CONDITIONS WILL DOMINATE THROUGH MONDAY.

OUTLOOK...
TUE...MVFR POSS NW HALF. VFR SE.
WED...MVFR POSS WITH
SHSN. THU...VFR. FRI...VFR.

&&

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

&&

$$
SYNOPSIS...DEVOIR/MARTIN
NEAR TERM...DANGELO/FITZGERALD
SHORT TERM...DEVOIR
LONG TERM...MARTIN
AVIATION...CERU/RXR







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

NWS SIOUX FALLS SD

 327 AM CST MON FEB 6 2012

.DISCUSSION.../ISSUED AT 900 PM CST/
MAIN CHALLENGE IN THE NEAR TERM IS THE FOG THAT HAS DEVELOPED
ACROSS EASTERN SECTIONS OF THE FORECAST AREA. ISSUED DENSE FOG
ADVISORY EARLIER FOR NORTHWEST IOWA...AND HAVE EXPANDED THE ADVISORY
TWO ROWS OF COUNTIES TO THE NORTH WITH LOW LEVEL SOUTHWEST FLOW
DRIVING THE FOG. FOG WILL LIKELY RUN INTO TERRAIN IN SOUTHWEST
MINNESOTA...SO POTENTIAL FOR ADDITIONAL EXPANSION IS SOMEWHAT
LIMITED.  EXPECT FOG TO ERODE ALONG THE WESTERN EDGE IN THE 16-17Z
TIMEFRAME IN SIMILAR FASHION TO YESTERDAY. FOG WILL HAVE AN EFFECT
ON DIURNAL TREND...AND HAVE SLOWED WARMING IN THE EAST COMPARED TO
MODEL TRENDS AND HAVE ALSO REDUCED HIGHS SLIGHTLY.

COLD FRONT IS EXPECTED TO DIVE INTO CWA LATE THIS AFTERNOON AND THIS
EVENING.  LOW LEVEL COLD AIR ADVECTION WILL KEEP ATMOSPHERE
MIXED...BUT DRY AIR WILL REALLY LIMIT POTENTIAL FOR ANY
PRECIPITATION.  DROPPED MENTION OF FLURRIES AFTER 06Z...BUT KEPT
MENTION IN FAR SOUTHERN EDGE OF CWA IN THE 12-18Z TIMEFRAME AS
SHALLOW CLOUD LAYER MAY DEVELOP AROUND 900 MB NEAR THE DENDRITIC
LAYER.  AM NOT EXPECTING ANYTHING MORE THAN FLURRIES FROM SHALLOW
SATURATED LAYER.

EVEN THOUGH 925 HPA TEMPS ARE EXPECTED TO COOL TO AROUND -10 C BY
MID DAY TUESDAY...TEMPERATURES WILL ONLY BE SLIGHTLY BELOW NORMAL
DUE TO LACK OF SNOW COVER AND MODIFYING AIRMASS ACROSS THE AREA.

MILD AIR RETURNS TO THE REGION MID WEEK BEFORE ANOTHER ARCTIC PUSH
MOVES INTO THE REGION ON THURSDAY. LEFT GUIDANCE FORECAST AS
IS...WITH GUIDANCE VALUES HEDGING TOWARD THE WARM SIDE OF POSSIBLE
SOLUTIONS. RIP AG.


&&

.AVIATION.../FOR THE 06Z TAF ISSUANCE/
STRATUS OVER NORTHWESTERN IOWA LATE THIS EVENING BEGINNING TO CREEP
SLOWLY BACK TO THE NORTH AS LOW LEVEL WINDS BECOMING SOUTHWESTERLY.
THIS WILL KEEP THAT AREA...INCLUDING KSUX WITH IFR/LIFR CEILINGS AND
MVFR/IFR VISIBILITIES THROUGH THE NIGHT. SOME UNCERTAINTY ON HOW FAR
NORTH STRATUS MAY PROGRESS OVERNIGHT WITH MODELS NOT HANDLING IT
WELL AT ALL...BUT MAY MAKE IT INTO THE KFSD AREA BY 06Z. FARTHER TO
THE NORTH...SKIES WILL REMAIN CLEAR OVERNIGHT...THOUGH THERE MAY BE
SOME LOCAL MVFR VISIBILITIES. A COLD FRONT WILL SWING THROUGH THE
REGION ON MONDAY...WITH STRATUS DISSIPATING WITH BETTER MIXING AHEAD
AND BEHIND THE FRONT. WINDS WILL PICK UP OUT OF THE NORTHWEST IN THE
LATER AFTERNOON BEHIND THE FRONT.

&&


.PREV DISCUSSION.../ISSUED AT 300 PM CST/
AGAIN STRATUS WITH SOME LIGHT FOG HAD BEEN STUBBORN ABOUT ERODING.
TODAY THE PROBLEM AREA IS EASIER TO DIAGNOSE DOWN IN NORTHWEST IOWA
AWAY FROM THE BEST MIXING AND CLOSEST TO THE SNOW COVER. SHORT TERM
MODELS KEEP THIS IN AND THIS LOOKS REASONABLE WITH THE FINE DETAILS
BEING THE TRICKY PART. WILL KEEP IN ALL NIGHT THIS AREA ALONG WITH
SOME AREAS OF FOG...AND EXPAND THE FOG MENTION BEYOND THE STRATUS
LATE TONIGHT IN THE EAST. AT THIS TIME AM NOT ANTICIPATING DENSE
FOG. THERE IS SOME QUESTION ABOUT REDEVELOPMENT FURTHER NORTHWEST
TOWARD DE SMET WHERE THE LAST OF THE STRATUS NORTH OF I90 IS
STUBBORNLY SHRINKING. WILL KEEP THE REDEVELOPMENT OUT FOR NOW.
ANOTHER AREA MIGHT BE SOUTHERN PART OF SOUTHWEST MN WHICH HAS ALSO
BEEN THE LATEST TO LOSE THE LOW CLOUDS...AND WHERE THE HRRR TRIES TO
BRING IT BACK IN SOME. WESTERN AREAS SHOULD STAY PRETTY CLEAR. LOW
TEMPERATURES SHOULD BE INT HE 20S. LIGHT WEST TO SOUTH WINDS SHOULD
RULE WEST AND NORTH...WITH LIGHT TO CALM SURFACE WINDS SOUTHEAST.
/ WILLIAMS

LINGERING STRATUS/FOG IN THE SOUTHEAST SHOULD CLEAR BY MID-LATE
MORNING AS LIGHT WINDS BECOME WESTERLY AHEAD OF THE COLD FRONT.
FRONTAL TIMING SIMILAR TO EARLIER SHIFT...ENTERING NORTHERN CWA LATE
MORNING...AND EXITING THE SOUTHEAST JUST AFTER SUNSET. SHOULD SEE
DECENT MIXING AHEAD OF AND IMMEDIATELY BEHIND THE FRONT...HELPING
MOST AREAS CLIMB INTO THE 40S WITH WARMEST READINGS ALONG AND SOUTH
OF I-90.

CLOUDS INCREASE BEHIND THE FRONT MONDAY NIGHT...WITH BAND OF STRATUS
POSSIBLE BEHIND THE FRONT DROPPING IN FROM THE NORTH...AND MID CLOUD
DECK EXPANDING ACROSS THE AREA FROM THE SOUTHWEST. THESE TWO LAYERS
OF MOISTURE NEVER REALLY SEEM TO CO-EXIST IN ANY ONE AREA UNTIL LATE
MONDAY NIGHT/EARLY TUESDAY OVER FAR SOUTHERN PARTS OF THE CWA...AND
WILL LIMIT MENTION OF A FEW FLURRIES TO THESE AREAS 06Z-18Z. NAM IS
PRODUCING SOME LIGHT QPF FARTHER NORTH MONDAY NIGHT...BUT SOUNDINGS
WOULD ONLY SUPPORT FREEZING DRIZZLE WITH TEMPERATURES IN THE CLOUD
LAYER NOT COLD ENOUGH TO INTRODUCE ICE INTO THE LAYER. NOT EVEN
HIGHLY CONFIDENT THAT THE BAND OF HIGHER RH INDICATED BY THE MODELS
WILL BE A BONAFIDE STRATUS BAND AND IS NOT JUST AN ARTIFACT OF THE
STRONG COLD ADVECTION...SO WILL LEAVE FORECAST DRY NORTH OF HIGHWAY
18.

LIMITED DIURNAL RANGE MONDAY NIGHT/TUESDAY WITH THE COLD ADVECTION
AND 925MB TEMPS FROM -8C TO -13C TUESDAY AFTERNOON...BUT COLD SNAP
WILL BE SHORT-LIVED AS WITH WEST-SOUTHWEST FLOW AND MOSTLY SUNNY
SKIES AIDING MIXING ON WEDNESDAY...SO WILL STICK WITH TEMPERATURES
MIXED A LITTLE HIGHER THAN 925MB...YIELDING HIGHS IN THE LOWER TO
MID 30S.

ARCTIC COLD FRONT PUSHES THROUGH THE REGION THURSDAY AS POLAR VORTEX
SETS UP CAMP OVER HUDSON BAY...AND MODELS STILL HAVING A TOUGH TIME
AGREEING ON WESTWARD EXTENT AND DURATION OF THE COLDEST AIR INTO THE
NORTHERN PLAINS. 00Z DETERMINISTIC RUNS FEATURED GFS ON COLD END OF
THE SPECTRUM /850MB TEMPS FRIDAY AFTN -16C TO -23C WEST TO EAST/...
WHILE ECMWF WAS QUITE A BIT WARMER /-3C TO -8C FOR SAME TIME FRAME/.
DIFFERENCES PERSISTED INTO SATURDAY...WHEN AFTERNOON 850MB TEMPS
RANGED FROM -10C TO -18C ON THE GFS...TO +10C TO +6C WEST TO EAST ON
THE ECMWF. 12Z DETERMINISTIC RUNS ESSENTIALLY FLIP-FLOPPED...THOUGH
WITH GENERAL TREND TOWARD THE MIDDLE WITH GFS TRENDING WARMER AND
ECMWF TRENDING COLDER THAN THEIR RESPECTIVE PREVIOUS RUNS. ALL THIS
LEADS TO VERY LOW CONFIDENCE IN TEMPERATURE FORECAST FOR THURSDAY
NIGHT THROUGH SATURDAY NIGHT AND WILL STICK FAIRLY CLOSE TO MIDDLE
GROUND WITH MODEL CONSENSUS FOR NOW. WHAT IS A LITTLE MORE CLEAR IS
THAT FRIDAY SHOULD BE THE COLDEST DAY OF THE LONG RANGE PERIOD...
WITH SUBTLE WARMUP FOR SATURDAY...AND GREATER WARMUP MORE LIKELY FOR
NEXT SUNDAY. ALSO FAIRLY CONFIDENT IN CONTINUED DRY FORECAST AS
MOISTURE QUITE LIMITED THROUGHOUT THE LATE WEEK/WEEKEND PERIOD OVER
OUR AREA.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.

&&

$$














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

NWS SIOUX FALLS SD

 1020 PM CST SUN FEB 5 2012

.DISCUSSION.../ISSUED AT 900 PM CST/
TRICKY FORECAST TONIGHT CONCERNING LOW TEMPERATURES. STRATUS IN NW
IA IS BEGINNING TO OOZE BACK NORTHWARD AS WINDS JUST OFF THE SURFACE
SHIFT TO THE SSW. IT APPEARS AT THE MOMENT...THAT AN APPROXIMATE
LINE FROM YANKTON...TO SIOUX FALLS/DELL RAPIDS...TO EVENTUALLY
WINDOM MN WILL BE ON THE EDGE OF THE STRATUS. THEREFORE LOW
TEMPERATURES IN THAT CORRIDOR WILL BE GREATLY INFLUENCED UP OR DOWN
BY THE CLOUDS. FOR NOW...LOWERED THE MIN TEMPERATURES AT SIOUX FALLS
AND YANKTON A LITTLE BIT...SINCE CURRENT READINGS ARE ALREADY NEAR
LOWS. ALSO LOWERED READINGS AT BROOKINGS AND HURON WHO COMMONLY
RADIATE OUT EVEN WITH A LIGHT SOUTH WIND. RAISED TEMPERATURES A TAD
IN NW IA DEEP INTO THE STRATUS...AS THAT AREA HAS NO CHANCE OF
CLEARING OUT. OTHERWISE...THE AREAS OF FOG WE HAVE GOING STILL LOOKS
VERY GOOD FOR THE AREA COVERED...PROJECTING THE STRATUS NORTHWARD.

&&

.AVIATION.../FOR THE 06Z TAF ISSUANCE/
STRATUS OVER NORTHWESTERN IOWA LATE THIS EVENING BEGINNING TO CREEP
SLOWLY BACK TO THE NORTH AS LOW LEVEL WINDS BECOMING SOUTHWESTERLY.
THIS WILL KEEP THAT AREA...INCLUDING KSUX WITH IFR/LIFR CEILINGS AND
MVFR/IFR VISIBILITIES THROUGH THE NIGHT. SOME UNCERTAINTY ON HOW FAR
NORTH STRATUS MAY PROGRESS OVERNIGHT WITH MODELS NOT HANDLING IT
WELL AT ALL...BUT MAY MAKE IT INTO THE KFSD AREA BY 06Z. FARTHER TO
THE NORTH...SKIES WILL REMAIN CLEAR OVERNIGHT...THOUGH THERE MAY BE
SOME LOCAL MVFR VISIBILITIES. A COLD FRONT WILL SWING THROUGH THE
REGION ON MONDAY...WITH STRATUS DISSIPATING WITH BETTER MIXING AHEAD
AND BEHIND THE FRONT. WINDS WILL PICK UP OUT OF THE NORTHWEST IN THE
LATER AFTERNOON BEHIND THE FRONT.

&&


.PREV DISCUSSION.../ISSUED AT 300 PM CST/
AGAIN STRATUS WITH SOME LIGHT FOG HAD BEEN STUBBORN ABOUT ERODING.
TODAY THE PROBLEM AREA IS EASIER TO DIAGNOSE DOWN IN NORTHWEST IOWA
AWAY FROM THE BEST MIXING AND CLOSEST TO THE SNOW COVER. SHORT TERM
MODELS KEEP THIS IN AND THIS LOOKS REASONABLE WITH THE FINE DETAILS
BEING THE TRICKY PART. WILL KEEP IN ALL NIGHT THIS AREA ALONG WITH
SOME AREAS OF FOG...AND EXPAND THE FOG MENTION BEYOND THE STRATUS
LATE TONIGHT IN THE EAST. AT THIS TIME AM NOT ANTICIPATING DENSE
FOG. THERE IS SOME QUESTION ABOUT REDEVELOPMENT FURTHER NORTHWEST
TOWARD DE SMET WHERE THE LAST OF THE STRATUS NORTH OF I90 IS
STUBBORNLY SHRINKING. WILL KEEP THE REDEVELOPMENT OUT FOR NOW.
ANOTHER AREA MIGHT BE SOUTHERN PART OF SOUTHWEST MN WHICH HAS ALSO
BEEN THE LATEST TO LOSE THE LOW CLOUDS...AND WHERE THE HRRR TRIES TO
BRING IT BACK IN SOME. WESTERN AREAS SHOULD STAY PRETTY CLEAR. LOW
TEMPERATURES SHOULD BE INT HE 20S. LIGHT WEST TO SOUTH WINDS SHOULD
RULE WEST AND NORTH...WITH LIGHT TO CALM SURFACE WINDS SOUTHEAST.
/ WILLIAMS

LINGERING STRATUS/FOG IN THE SOUTHEAST SHOULD CLEAR BY MID-LATE
MORNING AS LIGHT WINDS BECOME WESTERLY AHEAD OF THE COLD FRONT.
FRONTAL TIMING SIMILAR TO EARLIER SHIFT...ENTERING NORTHERN CWA LATE
MORNING...AND EXITING THE SOUTHEAST JUST AFTER SUNSET. SHOULD SEE
DECENT MIXING AHEAD OF AND IMMEDIATELY BEHIND THE FRONT...HELPING
MOST AREAS CLIMB INTO THE 40S WITH WARMEST READINGS ALONG AND SOUTH
OF I-90.

CLOUDS INCREASE BEHIND THE FRONT MONDAY NIGHT...WITH BAND OF STRATUS
POSSIBLE BEHIND THE FRONT DROPPING IN FROM THE NORTH...AND MID CLOUD
DECK EXPANDING ACROSS THE AREA FROM THE SOUTHWEST. THESE TWO LAYERS
OF MOISTURE NEVER REALLY SEEM TO CO-EXIST IN ANY ONE AREA UNTIL LATE
MONDAY NIGHT/EARLY TUESDAY OVER FAR SOUTHERN PARTS OF THE CWA...AND
WILL LIMIT MENTION OF A FEW FLURRIES TO THESE AREAS 06Z-18Z. NAM IS
PRODUCING SOME LIGHT QPF FARTHER NORTH MONDAY NIGHT...BUT SOUNDINGS
WOULD ONLY SUPPORT FREEZING DRIZZLE WITH TEMPERATURES IN THE CLOUD
LAYER NOT COLD ENOUGH TO INTRODUCE ICE INTO THE LAYER. NOT EVEN
HIGHLY CONFIDENT THAT THE BAND OF HIGHER RH INDICATED BY THE MODELS
WILL BE A BONAFIDE STRATUS BAND AND IS NOT JUST AN ARTIFACT OF THE
STRONG COLD ADVECTION...SO WILL LEAVE FORECAST DRY NORTH OF HIGHWAY
18.

LIMITED DIURNAL RANGE MONDAY NIGHT/TUESDAY WITH THE COLD ADVECTION
AND 925MB TEMPS FROM -8C TO -13C TUESDAY AFTERNOON...BUT COLD SNAP
WILL BE SHORT-LIVED AS WITH WEST-SOUTHWEST FLOW AND MOSTLY SUNNY
SKIES AIDING MIXING ON WEDNESDAY...SO WILL STICK WITH TEMPERATURES
MIXED A LITTLE HIGHER THAN 925MB...YIELDING HIGHS IN THE LOWER TO
MID 30S.

ARCTIC COLD FRONT PUSHES THROUGH THE REGION THURSDAY AS POLAR VORTEX
SETS UP CAMP OVER HUDSON BAY...AND MODELS STILL HAVING A TOUGH TIME
AGREEING ON WESTWARD EXTENT AND DURATION OF THE COLDEST AIR INTO THE
NORTHERN PLAINS. 00Z DETERMINISTIC RUNS FEATURED GFS ON COLD END OF
THE SPECTRUM /850MB TEMPS FRIDAY AFTN -16C TO -23C WEST TO EAST/...
WHILE ECMWF WAS QUITE A BIT WARMER /-3C TO -8C FOR SAME TIME FRAME/.
DIFFERENCES PERSISTED INTO SATURDAY...WHEN AFTERNOON 850MB TEMPS
RANGED FROM -10C TO -18C ON THE GFS...TO +10C TO +6C WEST TO EAST ON
THE ECMWF. 12Z DETERMINISTIC RUNS ESSENTIALLY FLIP-FLOPPED...THOUGH
WITH GENERAL TREND TOWARD THE MIDDLE WITH GFS TRENDING WARMER AND
ECMWF TRENDING COLDER THAN THEIR RESPECTIVE PREVIOUS RUNS. ALL THIS
LEADS TO VERY LOW CONFIDENCE IN TEMPERATURE FORECAST FOR THURSDAY
NIGHT THROUGH SATURDAY NIGHT AND WILL STICK FAIRLY CLOSE TO MIDDLE
GROUND WITH MODEL CONSENSUS FOR NOW. WHAT IS A LITTLE MORE CLEAR IS
THAT FRIDAY SHOULD BE THE COLDEST DAY OF THE LONG RANGE PERIOD...
WITH SUBTLE WARMUP FOR SATURDAY...AND GREATER WARMUP MORE LIKELY FOR
NEXT SUNDAY. ALSO FAIRLY CONFIDENT IN CONTINUED DRY FORECAST AS
MOISTURE QUITE LIMITED THROUGHOUT THE LATE WEEK/WEEKEND PERIOD OVER
OUR AREA.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.

&&

$$











AREA FORECAST DISCUSSION...UPDATED

NWS SAN ANGELO TX

 559 PM CST TUE FEB 7 2012

.DISCUSSION...
SEE AVIATION SECTION.

&&

.AVIATION...
VFR CONDITIONS...FOR THE MOST PART...WILL PREVAIL THROUGH THE NEXT 24
HOURS.THE POSSIBLE EXCEPTION IS AT KBBD AND KJCT BETWEEN 09Z AND
16Z WEDNESDAY. AREA OF CLOUDS WITH CEILINGS 4K-5K FT WILL OVERSPREAD
THE SOUTHERN PART OF WEST CENTRAL TEXAS THROUGH EARLY TONIGHT.
THIS TAF PACKAGE...BASED PARTLY ON GUIDANCE FROM THE 18Z NAM RH
AT 800MB...HAS CLOUD CEILINGS PERSISTING WELL INTO THE NIGHT AT
KSJT...KBBD AND KJCT. HOWEVER...WILL MONITOR SATELLITE TRENDS AND
MAY NEED TO AMEND WITH A LONGER PERIOD OF CLEARING AT THESE
SITES. OVERNIGHT...BOUNDARY LAYER MOISTURE FIELDS SUGGEST A LOW
CLOUD FIELD /WITH MVFR CEILINGS/ DEVELOPING ACROSS OUR EASTERN
COUNTIES. CARRYING A 2K-3K CEILING AT KBBD AND KJCT ROUGHLY
BETWEEN 09Z AND 16Z. ANTICIPATE THAT THE REST OF OUR AREA WILL
HAVE CLEAR TO PARTLY CLOUDY SKY CONDITION WEDNESDAY MORNING. IN
THE WAKE OF THE RECENT COLD FRONTAL PASSAGE... NORTH WINDS AT
10-15 KT WILL OCCUR THROUGH MUCH OF TONIGHT...WITH A FEW GUSTS TO
20 KT POSSIBLE THROUGH LATE EVENING. NORTH WINDS WILL VEER TO
NORTHEAST BY MIDDAY WEDNESDAY WITH A GRADUAL DECREASE IN SPEEDS.

19

&&

.PREV DISCUSSION... /ISSUED 325 PM CST TUE FEB 7 2012/

SHORT TERM...
COLD FRONT PROGRESSING SOUTHWARD ACROSS WEST CENTRAL TEXAS LATE THIS
AFTERNOON. LIFT WITH THE FRONT HAS HELPED EXPAND AN AREA OF LOW AND
MID CLOUDS ACROSS THE BIG COUNTRY. MODELS NOT DOING A GREAT JOB WITH
THESE CLOUDS...ALTHOUGH THE RUC HAS PICKED UP ON THEM TO SOME
DEGREE.  SUSPECT THESE CLOUDS WILL EXPAND SOUTH AND COVER MUCH OF
WEST CENTRAL TEXAS BY EVENING...BEFORE STARTING TO DECREASE.

DESPITE THE CLOUD COVER...STILL LOOKS TO BE A COLD NIGHT.
TEMPERATURES ACROSS THE PANHANDLE REMAIN IN THE LOW TO MID 30S THIS
AFTERNOON...SO AIR MASS IS CERTAINLY COLD. GUIDANCE NUMBERS ARE
PRETTY SIMILAR IN THE UPPER 20S AND LOWER 30S...AND NOT GOING TO
DEVIATE TOO MUCH. COLDEST READINGS WILL BE ACROSS THE NORTHERN AND
WESTERN BIG COUNTRY...WHERE AT LEAST SOME BREAKS IN THE CLOUDS WILL
DEVELOP.

COOL AGAIN ON WEDNESDAY...AS COLD ADVECTION CONTINUES. SURFACE HIGH
SLIDES OFF TO THE EAST INTO THE MISSISSIPPI VALLEY...SO WINDS WILL
BEGIN TO SWING AROUND TO THE EAST AND SOUTHEAST BY AFTERNOON.

07

LONG TERM...
AN UPPER LEVEL LOW WILL DEVELOP AT THE BASE OF THE UPPER LEVEL
TROUGH CURRENTLY OVER CALIFORNIA...THEN DIVE SOUTH TO SOUTHERN BAJA
CALIFORNIA BY THURSDAY MORNING. THIS WILL PUT WEST CENTRAL TEXAS IN
SOUTHWEST FLOW A LOT WITH INCREASING PACIFIC MOISTURE AND OCCASIONAL
DISTURBANCES TREKKING ACROSS THE REGION. AS THE PACIFIC MOISTURE
BEGINS TO INCREASE...CLOUD COVER WILL ALSO BE ON THE INCREASE.
EXPECT LOW TO MID LEVEL CLOUDS TO QUICKLY INCREASE BY EARLY THURSDAY
MORNING...WHICH SHOULD SERVE TO KEEP TEMPERATURES UP A
BIT...ESPECIALLY OVER THE SOUTHERN HALF OF THE AREA. LOW
TEMPERATURES ON THURSDAY MORNING WILL RANGE FROM THE LOWER 40S
SOUTH...TO NEAR 30 NORTH. A COOL/DREARY PATTERN WILL SETUP FOR
THURSDAY AND FRIDAY...WITH THE MAIN QUESTIONS BEING RAIN
CHANCES...AND QPF AMOUNTS. ECMWF AND GFS SOLUTIONS BEING TO DIVERGE
BEYOND THURSDAY AS THE GFS IS FASTER IN EJECTING THE LOW INTO NORTH
CENTRAL MEXICO...THEN TRACKING IT ACROSS TEXAS AS A WEAK OPEN WAVE.
THE ECMWF CONTINUES TO BE MUCH SLOWER...HANGING THE LOW OFF THE
PACIFIC COAST THROUGH SATURDAY. THE BEST DYNAMICS WITH THIS LOW WILL
REMAIN WELL SOUTH OF WEST CENTRAL TEXAS...AND HAVE TRIMMED POPS BACK
SLIGHTLY...THURSDAY AND FRIDAY. WOULD NOT BE SURPRISED TO SEE A FEW
SHOWERS AS OCCASIONAL DISTURBANCES EMBEDDED IN THE SOUTHWEST FLOW
ALOFT MOVE OVER THE AREA. DO NOT EXPECT MUCH QPF...AS ANY SHOWERS
THAT DO DEVELOP LOOK TO BE LIGHT AS THIS TIME. IN
ADDITION...DIFFERENCES ARISE IN THE HANDLING OF THE NEXT UPPER LEVEL
TROUGH MOVING ACROSS THE PLAINS ON FRIDAY. THE ECMWF IS DEEPER THAN
THE GFS WITH THE TROUGH...HENCE MORE AGGRESSIVE WITH THE
FRONT...PUSHING IT THROUGH THE AREA ON FRIDAY. AS THE FRONT MOVES
THROUGH...THE ECMWF DEVELOPS SHOWERS ALONG THE BOUNDARY ON FRIDAY.
FOR NOW...HAVE LEFT FRIDAY DRY...BUT FUTURE SHIFTS WILL NEED TO
MONITOR. THE NEXT ISSUE IS THE NEXT UPPER LEVEL TROUGH THAT IS
FORECAST TO SWING ACROSS THE PLAINS SUNDAY INTO MONDAY. MODELS HAVE
BEEN FAIRLY CONSISTENT IN SHOWING INCREASING RAIN CHANCES AHEAD OF
THIS TROUGH...AND HAVE ADDED IN SLIGHT CHANCE POPS SUNDAY AND SUNDAY
NIGHT.

DANIELS

&&

.PRELIMINARY POINT TEMPS/POPS...
ABILENE  28  47  32  56  37 /   0  10  10  10  20
SAN ANGELO  33  52  36  54  38 /   0  10  10  10  20
JUNCTION  36  56  39  56  39 /  10  10  10  20  20

&&

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

$$









AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 1145 AM CST MON FEB 6 2012

.SHORT TERM...UPDATE
444 AM CST MON FEB 6 2012

HAVE MADE A QUICK UPDATE TO THE FORECAST AS SOME FLURRIES HAVE
BEEN REPORTED ACROSS THE AREA. THESE FLURRIES SHOULD END LATER
THIS MORNING AS TEMPERATURES WARM AND THE STRATUS DECK THINS OUT.
ALSO...A FEW MORE RUNS OF THE HRRR HAVE COME IN AND CONTINUE TO
KEEP THE CLOUDS IN THIS AFTERNOON...SO HAVE BOOSTED THE CLOUDINESS
A BIT MORE.

PREVIOUS AFD...

ONCE AGAIN WE ARE LEFT WITH A STRATUS DECK TO CONTEND WITH TODAY
WHICH WILL LIKELY HOLD TEMPERATURES BACK A BIT BEFORE A COLD FRONT
COMES THROUGH LATE THIS AFTERNOON AND EVENING.

A CUT OFF MID LEVEL LOW CONTINUES TO SPIN ACROSS THE CENTRAL
ROCKIES AS THE POLAR VORTEX BEGINS ITS DESCENT THROUGH EASTERN
CANADA. AT THE SURFACE...A RIDGE OF HIGH PRESSURE HAS DROPPED TO
THE SOUTHERN PLAINS WHILE A COLD FRONT IS PUSHING SOUTH ACROSS
ONTARIO AND THE DAKOTAS. MEANWHILE...A LOAN CLUSTER OF STRATUS
REMAINS TRAPPED UNDER AN INVERSION AROUND 950MB AND COVERS ALL OF
IOWA...THE WESTERN TWO THIRDS OF WISCONSIN AND THE EASTERN THIRD
OF MINNESOTA. THE 06.00Z MPX RAOB SHOWS THAT THIS LAYER OF STRATUS
IS ABOUT 200FT THICK...WHICH SHOULD BE THIN ENOUGH FOR SOME EXTRA
WIND TURBULENCE AND WARMING SURFACE TEMPERATURES TO POKE SOME
HOLES IN IT. THIS HAS NOT BEEN THE CASE OVERNIGHT DESPITE THE
INCREASING SURFACE WINDS AS THE STRATUS REMAINS A UNIFIED LAYER.

AS HAS BEEN THE CASE NOW FOR THE PAST 4 DAYS AND WHAT SEEMS THE
REST OF THIS WINTER...THE FORECAST FOR TODAY RESTS SOLELY ON WHAT
THIS THIN LAYER OF STRATUS DECIDES TO DO. IF THE STRATUS LINGERS
THROUGH THE DAY...HIGH TEMPERATURES WILL REMAIN IN THE LOW TO MID
30S. HOWEVER...IF SKIES CLEAR OUT AND BECOME SUNNY...HIGHS WILL
LIKELY REACH THE MID 40S. THE 06.00Z TO 06.05Z HRRR CEILING
PROJECTIONS HAVE ALL HAD A PRETTY GOOD HANDLE ON THE CURRENT
STRATUS FIELD AND HAVE BEEN FAIRLY CONSISTENT WITH ITS FORECAST OF
KEEPING THE STRATUS IN TACT THROUGH THE MORNING AND EARLY
AFTERNOON. THE 06.05Z HRRR RUN DID SHOW SOME HOLES STARTING TO POP
UP IN THE EARLY AFTERNOON...WHICH SEEMS PLAUSIBLE GIVEN THE
SHALLOW CLOUD DEPTH AND BETTER MIXING DUE TO AN INCREASING LOW
LEVEL PRESSURE GRADIENT AND WINDS. THEREFORE...HAVE KEPT
TEMPERATURES DOWN THROUGH THE MORNING WITH THE CLOUD COVER
EXPECTED TO AT LEAST HOLD ON UNTIL LUNCHTIME WITH A QUICK JUMP IN
TEMPERATURES THIS AFTERNOON AS HOLES START TO DEVELOP. WOULD NOT
BE SURPRISED TO SEE A FEW HIGHER TEMPERATURES CROP UP THIS
AFTERNOON...BUT CONFIDENCE IS JUST NOT HIGH ENOUGH AT THIS POINT
TO HAVE MID TO UPPER 40S IN THE FORECAST.

THE COLD FRONT ALONG THE US/CANADIAN BORDER THEN WILL ENTER THE
NORTHERN PORTION OF THE FORECAST AREA LATE THIS AFTERNOON AND PASS
THROUGH THE SOUTHERN PORTION OF THE FORECAST AREA BY MIDNIGHT
TONIGHT. SOME POST-FRONTAL FLURRIES LOOK POSSIBLE AS THE
TEMPERATURES IN THE LOW LEVEL CLOUD LAYER DROP TOWARD -10C
TONIGHT. THE 06.00Z NAM/GFS/GEM ALL HAVE SOME SPOTTY QPF THAT
SHOWS UP TONIGHT WHICH IS LIKELY A RESULT OF A SLIGHTLY DEEPER
DENDRITIC GROWTH ZONE THAT TRIES TO DEVELOP BETWEEN 900-750MB. THE
ONLY FORCING WITH THIS SYSTEM IS WITH SOME WEAKLY SLOPED
FRONTOGENESIS WITH THE MID LEVEL TROUGH LAGGING FAR BEHIND.
THUS...AM NOT TOO HIGH ON THE CHANCES FOR GETTING AN ACCUMULATING
SNOW OUT OF THIS FEATURE.

BEYOND THIS IT WILL JUST BE A QUESTION OF WHEN SKIES CLEAR OUT AS
A RIDGE OF HIGH PRESSURE SETS UP ACROSS THE PLAINS AND GREAT LAKES.
THIS RIDGE WILL DROP TEMPERATURES DOWN TO SEASONAL LEVELS GOING INTO
MID WEEK WITH THE CLEARING LIKELY TAKING PLACE ON WEDNESDAY.

.LONG TERM...THURSDAY NIGHT THROUGH SUNDAY
257 AM CST MON FEB 6 2012

THE MAIN FOCUS IN THE LONG TERM CONTINUES TO BE WITH WHEN A COLD
FRONT WILL DROP DOWN AND HOW COLD WILL IT GET LATE IN THE WEEK
AND WEEKEND. IT APPEARS THAT THE 06.00Z GFS AND ECMWF HAVE
FINALLY COME TO A COMPROMISE WITH BRINGING A NORTHEAST TO
SOUTHWEST ORIENTATED COLD FRONT THROUGH THE REGION THURSDAY
AFTERNOON AND EVENING WITH NO PRECIPITATION OCCURRING IN THE
REGION. TEMPERATURES WILL COOL TO BELOW NORMAL WITH 850MB
TEMPERATURES DROPPING TO -20C FOR A PERIOD THURSDAY NIGHT INTO AT
LEAST FRIDAY. THE 06.00Z ECMWF IS A BIT FASTER WITH BRINGING
WARMER AIR BACK IN AT THE LOW LEVELS ON SATURDAY ALREADY WHILE THE
06.00Z GFS HOLDS ONTO THE COLDER AIR FOR LONGER. THUS...HAVE GONE
WITH THE COLDER TEMPERATURES THURSDAY THROUGH SATURDAY WITH A
WARMING TREND SUNDAY.

&&

.AVIATION...THIS AFTERNOON THROUGH TUESDAY
1145 AM CST MON FEB 6 2012

PIREPS FROM THIS MORNING INDICATED CLOUD DECK WAS ON THE ORDER OF 1K
TO 1.5K FT THICK...THUS INCREASED FORCING/MIXING WITH WEST/SOUTHWEST
WINDS AHEAD OF THE FRONT DROPPING THRU MN HAS BEEN ENOUGH TO BREAK
UP/ERODE THE  MVFR/IFR STRATUS OVER PARTS OF THE AREA. VIS IMAGERY
SHOWED CONTINUED EROSION OF THE CLOUDS WEST OF THE FCST AREA LATE
THIS MORNING...THUS TRENDED KRST/KLSE TAFS MORE OPTIMISTIC FOR THE
AFTERNOON HOURS...WITH VFR VSBYS AND THE LOW CLOUD LAYER BECOMING
SCT. SFC FRONT STILL DUE IN AROUND 00Z WITH A WIND SHIFT TO THE
NORTHWEST. HOWEVER NEXT MAINLY MVFR STRATUS DECK LAGS THE FRONT BY A
FEW HOURS AND DELAY ARRIVAL OF THESE CLOUDS INTO KRST/KLSE UNTIL
03Z. THIS MOISTURE RATHER SHALLOW AND REMOVED -SN/FLURRY MENTION
UNTIL LATER TONIGHT WHEN DEPTH OF MOISTURE LOOKS TO INCREASE TO
ABOUT 2KM ALONG WITH SOME WEAK FORCING/LIFT. BY LATE TONIGHT WHEN
MOISTURE IS DEEP ENOUGH CLOUD-TOP TEMPS PROGGED TO BE IN THE
-10C-12C RANGE...COLD ENOUGH FOR ICE IN THE CLOUDS AND PRECIP AS
FLURRIES. HOWEVER...IF CLOUD TOP TEMPS END UP MORE -8C TO -10C...
THREAT WOULD EXIST FOR PATCHY FREEZING DRIZZLE...BUT POST FRONTAL
AIRMASS AND ANTI-CYCLONIC LOW LEVEL NOT FAVORABLE FOR A DRIZZLE
SCENARIO AND LEFT THIS MENTION OUT FOR NOW. MOISTURE ONCE AGAIN
BECOME SHALLOW UNDER AN INVERSION NEAR 900MB BY LATER TUE MORNING.
FURTHER DRYING EXPECTED IN THE 950-900MB LAYER FOR TUE AFTERNOON
WITH CLOUD DECKS LOOKING TO BECOME SCT AFTER 18Z TUE.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
257 AM CST MON FEB 6 2012

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

&&

$$

SHORT TERM...HALBACH
LONG TERM....HALBACH
AVIATION.....RRS










AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 550 AM CST MON FEB 6 2012

.SHORT TERM...UPDATE
444 AM CST MON FEB 6 2012

HAVE MADE A QUICK UPDATE TO THE FORECAST AS SOME FLURRIES HAVE
BEEN REPORTED ACROSS THE AREA. THESE FLURRIES SHOULD END LATER
THIS MORNING AS TEMPERATURES WARM AND THE STRATUS DECK THINS OUT.
ALSO...A FEW MORE RUNS OF THE HRRR HAVE COME IN AND CONTINUE TO
KEEP THE CLOUDS IN THIS AFTERNOON...SO HAVE BOOSTED THE CLOUDINESS
A BIT MORE.

PREVIOUS AFD...

ONCE AGAIN WE ARE LEFT WITH A STRATUS DECK TO CONTEND WITH TODAY
WHICH WILL LIKELY HOLD TEMPERATURES BACK A BIT BEFORE A COLD FRONT
COMES THROUGH LATE THIS AFTERNOON AND EVENING.

A CUT OFF MID LEVEL LOW CONTINUES TO SPIN ACROSS THE CENTRAL
ROCKIES AS THE POLAR VORTEX BEGINS ITS DESCENT THROUGH EASTERN
CANADA. AT THE SURFACE...A RIDGE OF HIGH PRESSURE HAS DROPPED TO
THE SOUTHERN PLAINS WHILE A COLD FRONT IS PUSHING SOUTH ACROSS
ONTARIO AND THE DAKOTAS. MEANWHILE...A LOAN CLUSTER OF STRATUS
REMAINS TRAPPED UNDER AN INVERSION AROUND 950MB AND COVERS ALL OF
IOWA...THE WESTERN TWO THIRDS OF WISCONSIN AND THE EASTERN THIRD
OF MINNESOTA. THE 06.00Z MPX RAOB SHOWS THAT THIS LAYER OF STRATUS
IS ABOUT 200FT THICK...WHICH SHOULD BE THIN ENOUGH FOR SOME EXTRA
WIND TURBULENCE AND WARMING SURFACE TEMPERATURES TO POKE SOME
HOLES IN IT. THIS HAS NOT BEEN THE CASE OVERNIGHT DESPITE THE
INCREASING SURFACE WINDS AS THE STRATUS REMAINS A UNIFIED LAYER.

AS HAS BEEN THE CASE NOW FOR THE PAST 4 DAYS AND WHAT SEEMS THE
REST OF THIS WINTER...THE FORECAST FOR TODAY RESTS SOLELY ON WHAT
THIS THIN LAYER OF STRATUS DECIDES TO DO. IF THE STRATUS LINGERS
THROUGH THE DAY...HIGH TEMPERATURES WILL REMAIN IN THE LOW TO MID
30S. HOWEVER...IF SKIES CLEAR OUT AND BECOME SUNNY...HIGHS WILL
LIKELY REACH THE MID 40S. THE 06.00Z TO 06.05Z HRRR CEILING
PROJECTIONS HAVE ALL HAD A PRETTY GOOD HANDLE ON THE CURRENT
STRATUS FIELD AND HAVE BEEN FAIRLY CONSISTENT WITH ITS FORECAST OF
KEEPING THE STRATUS IN TACT THROUGH THE MORNING AND EARLY
AFTERNOON. THE 06.05Z HRRR RUN DID SHOW SOME HOLES STARTING TO POP
UP IN THE EARLY AFTERNOON...WHICH SEEMS PLAUSIBLE GIVEN THE
SHALLOW CLOUD DEPTH AND BETTER MIXING DUE TO AN INCREASING LOW
LEVEL PRESSURE GRADIENT AND WINDS. THEREFORE...HAVE KEPT
TEMPERATURES DOWN THROUGH THE MORNING WITH THE CLOUD COVER
EXPECTED TO AT LEAST HOLD ON UNTIL LUNCHTIME WITH A QUICK JUMP IN
TEMPERATURES THIS AFTERNOON AS HOLES START TO DEVELOP. WOULD NOT
BE SURPRISED TO SEE A FEW HIGHER TEMPERATURES CROP UP THIS
AFTERNOON...BUT CONFIDENCE IS JUST NOT HIGH ENOUGH AT THIS POINT
TO HAVE MID TO UPPER 40S IN THE FORECAST.

THE COLD FRONT ALONG THE US/CANADIAN BORDER THEN WILL ENTER THE
NORTHERN PORTION OF THE FORECAST AREA LATE THIS AFTERNOON AND PASS
THROUGH THE SOUTHERN PORTION OF THE FORECAST AREA BY MIDNIGHT
TONIGHT. SOME POST-FRONTAL FLURRIES LOOK POSSIBLE AS THE
TEMPERATURES IN THE LOW LEVEL CLOUD LAYER DROP TOWARD -10C
TONIGHT. THE 06.00Z NAM/GFS/GEM ALL HAVE SOME SPOTTY QPF THAT
SHOWS UP TONIGHT WHICH IS LIKELY A RESULT OF A SLIGHTLY DEEPER
DENDRITIC GROWTH ZONE THAT TRIES TO DEVELOP BETWEEN 900-750MB. THE
ONLY FORCING WITH THIS SYSTEM IS WITH SOME WEAKLY SLOPED
FRONTOGENESIS WITH THE MID LEVEL TROUGH LAGGING FAR BEHIND.
THUS...AM NOT TOO HIGH ON THE CHANCES FOR GETTING AN ACCUMULATING
SNOW OUT OF THIS FEATURE.

BEYOND THIS IT WILL JUST BE A QUESTION OF WHEN SKIES CLEAR OUT AS
A RIDGE OF HIGH PRESSURE SETS UP ACROSS THE PLAINS AND GREAT
LAKES. THIS RIDGE WILL DROP TEMPERATURES DOWN TO SEASONAL LEVELS GOING
INTO MID WEEK WITH THE CLEARING LIKELY TAKING PLACE ON WEDNESDAY.

.LONG TERM...THURSDAY NIGHT THROUGH SUNDAY
257 AM CST MON FEB 6 2012

THE MAIN FOCUS IN THE LONG TERM CONTINUES TO BE WITH WHEN A COLD
FRONT WILL DROP DOWN AND HOW COLD WILL IT GET LATE IN THE WEEK
AND WEEKEND. IT APPEARS THAT THE 06.00Z GFS AND ECMWF HAVE
FINALLY COME TO A COMPROMISE WITH BRINGING A NORTHEAST TO
SOUTHWEST ORIENTATED COLD FRONT THROUGH THE REGION THURSDAY
AFTERNOON AND EVENING WITH NO PRECIPITATION OCCURRING IN THE
REGION. TEMPERATURES WILL COOL TO BELOW NORMAL WITH 850MB
TEMPERATURES DROPPING TO -20C FOR A PERIOD THURSDAY NIGHT INTO AT
LEAST FRIDAY. THE 06.00Z ECMWF IS A BIT FASTER WITH BRINGING
WARMER AIR BACK IN AT THE LOW LEVELS ON SATURDAY ALREADY WHILE THE
06.00Z GFS HOLDS ONTO THE COLDER AIR FOR LONGER. THUS...HAVE GONE
WITH THE COLDER TEMPERATURES THURSDAY THROUGH SATURDAY WITH A
WARMING TREND SUNDAY.

&&

.AVIATION...TODAY AND TONIGHT
550 AM CST MON FEB 6 2012

STRATUS WILL PERSIST THROUGH MIDDAY TODAY AT THE TAF SITES
PRODUCING LIFR CONDITIONS AT KRST AND IFR CONDITIONS AT KLSE. PLAN
ON CLOUD BASES IN THE 200 TO 400 FT RANGE THROUGH 18Z TODAY AT
KRST...AND 700 TO 900 FT AT KLSE THROUGH 19Z. GUIDANCE IS
SUGGESTING THE OVERCAST STRATUS WILL BECOME SCATTERED THIS
AFTERNOON AHEAD OF A COLD FRONT ADVANCING SOUTHEAST FROM CENTRAL
MINNESOTA THROUGH NORTHERN WISCONSIN. LOOK FOR A FEW BREAKS IN THE
CLOUDS THIS AFTERNOON WITH A SHORT WINDOW OF VFR
CONDITIONS...MAINLY AFTER 19Z. MVFR STRATUS WILL MOVE BACK INTO THE
TAF SITES LATE THIS AFTERNOON INTO EARLY THIS EVENING AS THE COLD
FRONT MOVES INTO THE AREA. PLAN ON CLOUD BASES IN THE THE 1000 TO
1500 FT RANGE. NAM FORECAST SOUNDINGS ARE INDICATING THE POTENTIAL
FOR LIGHT FREEZING DRIZZLE THIS EVENING AS THE FRONT MOVES
IN...WITH NO ICE CRYSTALS ALOFT IN THE 03Z TO 08Z TIMEFRAME. THE
GFS ON THE OTHER HAND...SHOWS ICE ALOFT WITH FLURRIES DEVELOPING
ALONG AND BEHIND THE FRONT. CONFIDENCE LOW ON FREEZING DRIZZLE
THIS EVENING SO HAVE NOT INCLUDED IT IN THE TAFS AT THIS TIME.
WILL HAVE TO KEEP A CLOSE WATCH ON THE NEXT SET OF MODELS RUNS AND
OBSERVATIONS UPSTREAM THROUGH THE DAY. HAVE DECIDED TO MAINTAIN
FLURRIES AT BOTH TAF SITES STARTING AT 00Z AT KRST AND AT 01Z AT
KLSE. PLAN ON MVFR CONDITIONS THROUGH THE NIGHT. WINDS WILL VEER TO
THE NORTHWEST LATE THIS AFTERNOON AS THE FRONT MOVES IN...WITH
WIND SPEEDS OF 7 TO 14 KTS EXPECTED.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
257 AM CST MON FEB 6 2012

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

&&

$$

SHORT TERM...HALBACH
LONG TERM....HALBACH
AVIATION.....WETENKAMP







AREA FORECAST DISCUSSION...UPDATED

NWS LA CROSSE WI

 444 AM CST MON FEB 6 2012

.SHORT TERM...UPDATE
444 AM CST MON FEB 6 2012

HAVE MADE A QUICK UPDATE TO THE FORECAST AS SOME FLURRIES HAVE
BEEN REPORTED ACROSS THE AREA. THESE FLURRIES SHOULD END LATER
THIS MORNING AS TEMPERATURES WARM AND THE STRATUS DECK THINS OUT.
ALSO...A FEW MORE RUNS OF THE HRRR HAVE COME IN AND CONTINUE TO
KEEP THE CLOUDS IN THIS AFTERNOON...SO HAVE BOOSTED THE CLOUDINESS
A BIT MORE.

PREVIOUS AFD...

ONCE AGAIN WE ARE LEFT WITH A STRATUS DECK TO CONTEND WITH TODAY
WHICH WILL LIKELY HOLD TEMPERATURES BACK A BIT BEFORE A COLD FRONT
COMES THROUGH LATE THIS AFTERNOON AND EVENING.

A CUT OFF MID LEVEL LOW CONTINUES TO SPIN ACROSS THE CENTRAL
ROCKIES AS THE POLAR VORTEX BEGINS ITS DESCENT THROUGH EASTERN
CANADA. AT THE SURFACE...A RIDGE OF HIGH PRESSURE HAS DROPPED TO
THE SOUTHERN PLAINS WHILE A COLD FRONT IS PUSHING SOUTH ACROSS
ONTARIO AND THE DAKOTAS. MEANWHILE...A LOAN CLUSTER OF STRATUS
REMAINS TRAPPED UNDER AN INVERSION AROUND 950MB AND COVERS ALL OF
IOWA...THE WESTERN TWO THIRDS OF WISCONSIN AND THE EASTERN THIRD
OF MINNESOTA. THE 06.00Z MPX RAOB SHOWS THAT THIS LAYER OF STRATUS
IS ABOUT 200FT THICK...WHICH SHOULD BE THIN ENOUGH FOR SOME EXTRA
WIND TURBULENCE AND WARMING SURFACE TEMPERATURES TO POKE SOME
HOLES IN IT. THIS HAS NOT BEEN THE CASE OVERNIGHT DESPITE THE
INCREASING SURFACE WINDS AS THE STRATUS REMAINS A UNIFIED LAYER.

AS HAS BEEN THE CASE NOW FOR THE PAST 4 DAYS AND WHAT SEEMS THE
REST OF THIS WINTER...THE FORECAST FOR TODAY RESTS SOLELY ON WHAT
THIS THIN LAYER OF STRATUS DECIDES TO DO. IF THE STRATUS LINGERS
THROUGH THE DAY...HIGH TEMPERATURES WILL REMAIN IN THE LOW TO MID
30S. HOWEVER...IF SKIES CLEAR OUT AND BECOME SUNNY...HIGHS WILL
LIKELY REACH THE MID 40S. THE 06.00Z TO 06.05Z HRRR CEILING
PROJECTIONS HAVE ALL HAD A PRETTY GOOD HANDLE ON THE CURRENT
STRATUS FIELD AND HAVE BEEN FAIRLY CONSISTENT WITH ITS FORECAST OF
KEEPING THE STRATUS IN TACT THROUGH THE MORNING AND EARLY
AFTERNOON. THE 06.05Z HRRR RUN DID SHOW SOME HOLES STARTING TO POP
UP IN THE EARLY AFTERNOON...WHICH SEEMS PLAUSIBLE GIVEN THE
SHALLOW CLOUD DEPTH AND BETTER MIXING DUE TO AN INCREASING LOW
LEVEL PRESSURE GRADIENT AND WINDS. THEREFORE...HAVE KEPT
TEMPERATURES DOWN THROUGH THE MORNING WITH THE CLOUD COVER
EXPECTED TO AT LEAST HOLD ON UNTIL LUNCHTIME WITH A QUICK JUMP IN
TEMPERATURES THIS AFTERNOON AS HOLES START TO DEVELOP. WOULD NOT
BE SURPRISED TO SEE A FEW HIGHER TEMPERATURES CROP UP THIS
AFTERNOON...BUT CONFIDENCE IS JUST NOT HIGH ENOUGH AT THIS POINT
TO HAVE MID TO UPPER 40S IN THE FORECAST.

THE COLD FRONT ALONG THE US/CANADIAN BORDER THEN WILL ENTER THE
NORTHERN PORTION OF THE FORECAST AREA LATE THIS AFTERNOON AND PASS
THROUGH THE SOUTHERN PORTION OF THE FORECAST AREA BY MIDNIGHT
TONIGHT. SOME POST-FRONTAL FLURRIES LOOK POSSIBLE AS THE
TEMPERATURES IN THE LOW LEVEL CLOUD LAYER DROP TOWARD -10C
TONIGHT. THE 06.00Z NAM/GFS/GEM ALL HAVE SOME SPOTTY QPF THAT
SHOWS UP TONIGHT WHICH IS LIKELY A RESULT OF A SLIGHTLY DEEPER
DENDRITIC GROWTH ZONE THAT TRIES TO DEVELOP BETWEEN 900-750MB. THE
ONLY FORCING WITH THIS SYSTEM IS WITH SOME WEAKLY SLOPED
FRONTOGENESIS WITH THE MID LEVEL TROUGH LAGGING FAR BEHIND.
THUS...AM NOT TOO HIGH ON THE CHANCES FOR GETTING AN ACCUMULATING
SNOW OUT OF THIS FEATURE.

BEYOND THIS IT WILL JUST BE A QUESTION OF WHEN SKIES CLEAR OUT AS
A RIDGE OF HIGH PRESSURE SETS UP ACROSS THE PLAINS AND GREAT
LAKES. THIS RIDGE WILL DROP TEMPERATURES DOWN TO SEASONAL LEVELS GOING
INTO MID WEEK WITH THE CLEARING LIKELY TAKING PLACE ON WEDNESDAY.

.LONG TERM...THURSDAY NIGHT THROUGH SUNDAY
257 AM CST MON FEB 6 2012

THE MAIN FOCUS IN THE LONG TERM CONTINUES TO BE WITH WHEN A COLD
FRONT WILL DROP DOWN AND HOW COLD WILL IT GET LATE IN THE WEEK
AND WEEKEND. IT APPEARS THAT THE 06.00Z GFS AND ECMWF HAVE
FINALLY COME TO A COMPROMISE WITH BRINGING A NORTHEAST TO
SOUTHWEST ORIENTATED COLD FRONT THROUGH THE REGION THURSDAY
AFTERNOON AND EVENING WITH NO PRECIPITATION OCCURRING IN THE
REGION. TEMPERATURES WILL COOL TO BELOW NORMAL WITH 850MB
TEMPERATURES DROPPING TO -20C FOR A PERIOD THURSDAY NIGHT INTO AT
LEAST FRIDAY. THE 06.00Z ECMWF IS A BIT FASTER WITH BRINGING
WARMER AIR BACK IN AT THE LOW LEVELS ON SATURDAY ALREADY WHILE THE
06.00Z GFS HOLDS ONTO THE COLDER AIR FOR LONGER. THUS...HAVE GONE
WITH THE COLDER TEMPERATURES THURSDAY THROUGH SATURDAY WITH A
WARMING TREND SUNDAY.

&&

.AVIATION...THROUGH 06Z TUESDAY
1135 PM CST SUN FEB 5 2012

AT 05Z A LARGE AREA OF STRATUS WAS OVER THE UPPER MISSISSIPPI
RIVER VALLEY REGION. THE BACK EDGE WAS PUSHING INTO SOUTH CENTRAL
MINNESOTA. HOWEVER...MORE STRATUS WAS LIFTING NORTHWARD OUT OF
IOWA INTO SOUTHWEST MINNESOTA. MODELS HAVE STRUGGLED OVER THE PAST
FEW DAYS WITH THE TREND TO CLEAR IT OUT TOO QUICKLY DURING THE DAY
AND THE 06.00Z NAM AGAIN DOING THE SAME THING. 06.02Z HRRR SHOWING
STRATUS TO REMAIN IN PLACE THROUGH AT LEAST 18Z AND THIS GOING
WITH A MORE PESSIMISTIC FORECAST. CAN NOT RULE OUT SOME BRIEF
CLEARING AFTER 18Z-20Z MONDAY...BUT IT WILL BE SHORT LIVED AS A
COLD FRONT WILL DROP SOUTHWARD THROUGH THE AREA...WITH ALL THE
MODELS SHOWING POST FRONTAL STRATUS TO MOVE BACK IN AROUND 00Z.
THUS WILL KEEP THE IFR CONDITIONS GOING THROUGH MUCH OF THE DAY
WITH A BRIEF BREAK THIS AFTERNOON BEFORE MVFR POST FRONTAL
CEILINGS MOVE IN.

NEXT QUESTION IS ON ANY POST FRONTAL PRECIPITATION CHANCES. 06.00Z
NAM AND GFS BOTH SHOWING SOME LIGHT PRECIPITATION. NAM IS THE
EARLIEST IN THE EVENING...WHILE THE GFS WOULD SUGGEST AFTER
MIDNIGHT. ONE CONCERN OF ANYTHING FALLING IN THE EVENING...IS THE
POTENTIAL LACK OF ICE CRYSTALS IN THE CLOUDS WHICH COULD RESULT IN
SOME PATCHY FREEZING DRIZZLE RATHER THAN FLURRIES. FOR NOW WILL
JUST MENTION FLURRIES...BUT THIS WILL HAVE TO BE MONITORED.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
257 AM CST MON FEB 6 2012

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

&&

$$

SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...RABERDING







AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 257 AM CST MON FEB 6 2012

.SHORT TERM...TODAY THROUGH THURSDAY
257 AM CST MON FEB 6 2012

ONCE AGAIN WE ARE LEFT WITH A STRATUS DECK TO CONTEND WITH TODAY
WHICH WILL LIKELY HOLD TEMPERATURES BACK A BIT BEFORE A COLD FRONT
COMES THROUGH LATE THIS AFTERNOON AND EVENING.

A CUT OFF MID LEVEL LOW CONTINUES TO SPIN ACROSS THE CENTRAL
ROCKIES AS THE POLAR VORTEX BEGINS ITS DESCENT THROUGH EASTERN
CANADA. AT THE SURFACE...A RIDGE OF HIGH PRESSURE HAS DROPPED TO
THE SOUTHERN PLAINS WHILE A COLD FRONT IS PUSHING SOUTH ACROSS
ONTARIO AND THE DAKOTAS. MEANWHILE...A LOAN CLUSTER OF STRATUS
REMAINS TRAPPED UNDER AN INVERSION AROUND 950MB AND COVERS ALL OF
IOWA...THE WESTERN TWO THIRDS OF WISCONSIN AND THE EASTERN THIRD
OF MINNESOTA. THE 06.00Z MPX RAOB SHOWS THAT THIS LAYER OF STRATUS
IS ABOUT 200FT THICK...WHICH SHOULD BE THIN ENOUGH FOR SOME EXTRA
WIND TURBULENCE AND WARMING SURFACE TEMPERATURES TO POKE SOME
HOLES IN IT. THIS HAS NOT BEEN THE CASE OVERNIGHT DESPITE THE
INCREASING SURFACE WINDS AS THE STRATUS REMAINS A UNIFIED LAYER.

AS HAS BEEN THE CASE NOW FOR THE PAST 4 DAYS AND WHAT SEEMS THE
REST OF THIS WINTER...THE FORECAST FOR TODAY RESTS SOLELY ON WHAT
THIS THIN LAYER OF STRATUS DECIDES TO DO. IF THE STRATUS LINGERS
THROUGH THE DAY...HIGH TEMPERATURES WILL REMAIN IN THE LOW TO MID
30S. HOWEVER...IF SKIES CLEAR OUT AND BECOME SUNNY...HIGHS WILL
LIKELY REACH THE MID 40S. THE 06.00Z TO 06.05Z HRRR CEILING
PROJECTIONS HAVE ALL HAD A PRETTY GOOD HANDLE ON THE CURRENT
STRATUS FIELD AND HAVE BEEN FAIRLY CONSISTENT WITH ITS FORECAST OF
KEEPING THE STRATUS IN TACT THROUGH THE MORNING AND EARLY
AFTERNOON. THE 06.05Z HRRR RUN DID SHOW SOME HOLES STARTING TO POP
UP IN THE EARLY AFTERNOON...WHICH SEEMS PLAUSIBLE GIVEN THE
SHALLOW CLOUD DEPTH AND BETTER MIXING DUE TO AN INCREASING LOW
LEVEL PRESSURE GRADIENT AND WINDS. THEREFORE...HAVE KEPT
TEMPERATURES DOWN THROUGH THE MORNING WITH THE CLOUD COVER
EXPECTED TO AT LEAST HOLD ON UNTIL LUNCHTIME WITH A QUICK JUMP IN
TEMPERATURES THIS AFTERNOON AS HOLES START TO DEVELOP. WOULD NOT
BE SURPRISED TO SEE A FEW HIGHER TEMPERATURES CROP UP THIS
AFTERNOON...BUT CONFIDENCE IS JUST NOT HIGH ENOUGH AT THIS POINT
TO HAVE MID TO UPPER 40S IN THE FORECAST.

THE COLD FRONT ALONG THE US/CANADIAN BORDER THEN WILL ENTER THE
NORTHERN PORTION OF THE FORECAST AREA LATE THIS AFTERNOON AND PASS
THROUGH THE SOUTHERN PORTION OF THE FORECAST AREA BY MIDNIGHT
TONIGHT. SOME POST-FRONTAL FLURRIES LOOK POSSIBLE AS THE
TEMPERATURES IN THE LOW LEVEL CLOUD LAYER DROP TOWARD -10C
TONIGHT. THE 06.00Z NAM/GFS/GEM ALL HAVE SOME SPOTTY QPF THAT
SHOWS UP TONIGHT WHICH IS LIKELY A RESULT OF A SLIGHTLY DEEPER
DENDRITIC GROWTH ZONE THAT TRIES TO DEVELOP BETWEEN 900-750MB. THE
ONLY FORCING WITH THIS SYSTEM IS WITH SOME WEAKLY SLOPED
FRONTOGENESIS WITH THE MID LEVEL TROUGH LAGGING FAR BEHIND.
THUS...AM NOT TOO HIGH ON THE CHANCES FOR GETTING AN ACCUMULATING
SNOW OUT OF THIS FEATURE.

BEYOND THIS IT WILL JUST BE A QUESTION OF WHEN SKIES CLEAR OUT AS
A RIDGE OF HIGH PRESSURE SETS UP ACROSS THE PLAINS AND GREAT
LAKES. THIS RIDGE WILL DROP TEMPERATURES DOWN TO SEASONAL LEVELS GOING
INTO MID WEEK WITH THE CLEARING LIKELY TAKING PLACE ON WEDNESDAY.

.LONG TERM...THURSDAY NIGHT THROUGH SUNDAY
257 AM CST MON FEB 6 2012

THE MAIN FOCUS IN THE LONG TERM CONTINUES TO BE WITH WHEN A COLD
FRONT WILL DROP DOWN AND HOW COLD WILL IT GET LATE IN THE WEEK
AND WEEKEND. IT APPEARS THAT THE 06.00Z GFS AND ECMWF HAVE
FINALLY COME TO A COMPROMISE WITH BRINGING A NORTHEAST TO
SOUTHWEST ORIENTATED COLD FRONT THROUGH THE REGION THURSDAY
AFTERNOON AND EVENING WITH NO PRECIPITATION OCCURRING IN THE
REGION. TEMPERATURES WILL COOL TO BELOW NORMAL WITH 850MB
TEMPERATURES DROPPING TO -20C FOR A PERIOD THURSDAY NIGHT INTO AT
LEAST FRIDAY. THE 06.00Z ECMWF IS A BIT FASTER WITH BRINGING
WARMER AIR BACK IN AT THE LOW LEVELS ON SATURDAY ALREADY WHILE THE
06.00Z GFS HOLDS ONTO THE COLDER AIR FOR LONGER. THUS...HAVE GONE
WITH THE COLDER TEMPERATURES THURSDAY THROUGH SATURDAY WITH A
WARMING TREND SUNDAY.

&&

.AVIATION...THROUGH 06Z TUESDAY
1135 PM CST SUN FEB 5 2012

AT 05Z A LARGE AREA OF STRATUS WAS OVER THE UPPER MISSISSIPPI
RIVER VALLEY REGION. THE BACK EDGE WAS PUSHING INTO SOUTH CENTRAL
MINNESOTA. HOWEVER...MORE STRATUS WAS LIFTING NORTHWARD OUT OF
IOWA INTO SOUTHWEST MINNESOTA. MODELS HAVE STRUGGLED OVER THE PAST
FEW DAYS WITH THE TREND TO CLEAR IT OUT TOO QUICKLY DURING THE DAY
AND THE 06.00Z NAM AGAIN DOING THE SAME THING. 06.02Z HRRR SHOWING
STRATUS TO REMAIN IN PLACE THROUGH AT LEAST 18Z AND THIS GOING
WITH A MORE PESSIMISTIC FORECAST. CAN NOT RULE OUT SOME BRIEF
CLEARING AFTER 18Z-20Z MONDAY...BUT IT WILL BE SHORT LIVED AS A
COLD FRONT WILL DROP SOUTHWARD THROUGH THE AREA...WITH ALL THE
MODELS SHOWING POST FRONTAL STRATUS TO MOVE BACK IN AROUND 00Z.
THUS WILL KEEP THE IFR CONDITIONS GOING THROUGH MUCH OF THE DAY
WITH A BRIEF BREAK THIS AFTERNOON BEFORE MVFR POST FRONTAL
CEILINGS MOVE IN.

NEXT QUESTION IS ON ANY POST FRONTAL PRECIPITATION CHANCES. 06.00Z
NAM AND GFS BOTH SHOWING SOME LIGHT PRECIPITATION. NAM IS THE
EARLIEST IN THE EVENING...WHILE THE GFS WOULD SUGGEST AFTER
MIDNIGHT. ONE CONCERN OF ANYTHING FALLING IN THE EVENING...IS THE
POTENTIAL LACK OF ICE CRYSTALS IN THE CLOUDS WHICH COULD RESULT IN
SOME PATCHY FREEZING DRIZZLE RATHER THAN FLURRIES. FOR NOW WILL
JUST MENTION FLURRIES...BUT THIS WILL HAVE TO BE MONITORED.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
257 AM CST MON FEB 6 2012

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

&&

$$

SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...RABERDING







AREA FORECAST DISCUSSION

NWS LA CROSSE WI

 1135 PM CST SUN FEB 5 2012

.SHORT TERM...TONIGHT THROUGH WEDNESDAY
340 PM CST SUN FEB 5 2012

AT 3 PM...A 1033 MB HIGH WAS LOCATED ACROSS NEBRASKA AND KANSAS. A
SUBSIDENCE INVERSION ASSOCIATED WITH THIS HIGH REMAINS ACROSS THE
UPPER MISSISSIPPI RIVER VALLEY. MOISTURE TRAPPED BENEATH THIS
INVERSION HAS KEPT SKIES GENERALLY CLOUDY AND THIS HAS PREVENTED
THE TEMPERATURES FROM RISING OUT OF THE LOWER 30S. THE ONLY
EXCEPTION IS NORTH CENTRAL AND CENTRAL WISCONSIN WHERE THERE HAS
BEEN SUNSHINE MUCH OF THE AFTERNOON...AND THIS ALLOWED
TEMPERATURES TO CLIMB INTO THE MID AND UPPER 30S IN THESE AREAS.
WITH LOW CLOUDS SPREADING EAST...THESE AREAS WILL LIKELY HAVE TO
CONTEND WITH SOME CLOUDS FOR AT LEAST THIS EVENING.

THE MAIN FORECAST QUESTION TONIGHT AND EARLY MONDAY IS WHETHER THE
CLEARING LOCATED WILL MAKE IT INTO THE AREA. HRRR AND RUC SUGGEST
THAT THIS CLEARING WILL NOT MAKE IT INTO MUCH OF THE AREA /ONE
EXCEPTION IS NORTH CENTRAL WISCONSIN/ TONIGHT...AND WE WILL HAVE
TO WAIT UNTIL MONDAY MORNING WHEN THE WESTERLY DOWN SLOPE WIND MOVES
INTO THE AREA AHEAD OF THE FRONT. HOWEVER THERE IS ALSO A POSSIBILITY
THAT THIS AIR MASS MAY BE ISENTOPICALLY LIFTED UP AND OVER THE LOW
LEVEL MOISTURE AND THE AREA WILL REMAIN IN CLOUDS. WITH QUITE A
BIT OF CLEARING TAKING PLACE ACROSS THE DAKOTAS... DECIDED TO GO
MORE OPTIMISTIC. IF WE ARE ABLE TO GET SOME SUNSHINE...TEMPERATURES
WILL CLIMB INTO THE MID AND UPPER 40S. HOWEVER IF THE CLOUDS FAIL
TO BREAK UP...TEMPERATURES WILL REMAIN IN THE 30S. SINCE THERE IS
SOME UNCERTAINTY...DECIDED TO TAKE A BIT OF CONSERVATIVE APPROACH
AND JUST GO WITH TEMPERATURES IN THE LOWER AND MID 40S.

UNLIKE YESTERDAY...THE MODELS HAVE ONCE AGAIN HAVE SPEED UP THE
CANADIAN COLD FRONT. IT NOW LOOKS LIKE THE FRONT WILL MOVE THROUGH
THE AREAS NORTH OF THE INTERSTATE 90 CORRIDOR LATE MONDAY
AFTERNOON AND THROUGH THE REMAINDER OF THE AREA DURING THE
EVENING. THE COLD AIR IS LAGGING THIS FRONT BY ABOUT 9 TO
12 HOURS...SO NOT EXPECTING THE LOWS ON MONDAY NIGHT TO BE
SIGNIFICANTLY COLDER THAN THEY ARE TONIGHT. IN THE WAKE OF THIS
FRONT...IT CONTINUES TO LOOK LIKE THERE WILL BE CLOUDS AND
FLURRIES. THE NAM/WRF CONTINUES TO HAVE DEEPER MOISTURE THAN THE
GFS...BUT THERE IS NOT ENOUGH OF A DIFFERENCE TO PRECLUDE FLURRIES
FROM OCCURRING ON MONDAY NIGHT AND TUESDAY.

IN ADDITION OVER THE PAST COUPLE OF DAYS...IT LOOKED LIKE SKIES
WOULD CLEAR OUT QUICKLY BEHIND THE FRONT...BUT A CAREFUL
EXAMINATION OF SOUNDINGS AND THE LAYER BELOW 875 MB LOOKS LIKE A
DECK OF STRATUS WILL LINGER ACROSS THE AREA THROUGH TUESDAY...AND
THEN MODELS DIFFER WITH THE GFS CLEARING MUCH OF THE AREA OUT ON
TUESDAY NIGHT AND THE NAM/WRF KEEPING THE AREA CLOUDY THROUGH
WEDNESDAY. ACTUALLY PREFER THE LATTER SOLUTION. HOWEVER WITH SUCH
A DIFFERENCE IN THE MODELS...DECIDED TO JUST GO WITH A BLEND OF
THEM.

.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
340 PM CST SUN FEB 5 2012

ON THURSDAY...THE 05.12Z MODELS CONTINUE TO SUGGEST THAT SOME
WARMING WILL TAKE PLACE AHEAD OF THE NEXT CANADIAN COLD FRONT. THE
ECMWF ACTUALLY WARMS TEMPERATURES IN THE UPPER 30S. MEANWHILE THE
GEM KEEPS TEMPERATURES MAINLY IN THE MID AND UPPER 20S. SINCE
THERE WAS SUCH A DIFFERENCE AND THE ECMWF USUALLY DOES BETTER FOR
THIS TIME PERIOD...DECIDED TO GO WITH A BLEND OF THESE TWO.

ON FRIDAY...IT CONTINUE TO LOOK LIKE THE COLDEST AIR WILL BE
LOCATED ACROSS THE AREA. HOWEVER WITH THIS SAID...IT IS STILL A
MUCH WARMER SOLUTION THAN WHAT IT LOOKED LIKE 3 DAYS AGO. HIGH
TEMPERATURES ON THIS DAY WILL LIKELY RANGE FROM THE TEENS TO MID
20S WHICH IS ONLY 5 TO 10 DEGREES BELOW NORMAL.

LIKE THE PAST COUPLE OF DAYS...IT LOOKS LIKE THE LONG WAVE TROUGH
WILL MOVE QUICKLY OUT OF THE AREA DURING NEXT WEEKEND...AND THE
AREA WILL ONCE AGAIN SEE A RETURN TO ABOVE-NORMAL TEMPERATURES.
THE ECMWF IS BY FAR THE MOST AGGRESSIVE WITH ITS HIGH TEMPERATURES
IN THE MID AND UPPER 40S BY SUNDAY.

&&

.AVIATION...THROUGH 06Z TUESDAY
1135 PM CST SUN FEB 5 2012

AT 05Z A LARGE AREA OF STRATUS WAS OVER THE UPPER MISSISSIPPI
RIVER VALLEY REGION. THE BACK EDGE WAS PUSHING INTO SOUTH CENTRAL
MINNESOTA. HOWEVER...MORE STRATUS WAS LIFTING NORTHWARD OUT OF
IOWA INTO SOUTHWEST MINNESOTA. MODELS HAVE STRUGGLED OVER THE PAST
FEW DAYS WITH THE TREND TO CLEAR IT OUT TOO QUICKLY DURING THE DAY
AND THE 06.00Z NAM AGAIN DOING THE SAME THING. 06.02Z HRRR SHOWING
STRATUS TO REMAIN IN PLACE THROUGH AT LEAST 18Z AND THIS GOING
WITH A MORE PESSIMISTIC FORECAST. CAN NOT RULE OUT SOME BRIEF
CLEARING AFTER 18Z-20Z MONDAY...BUT IT WILL BE SHORT LIVED AS A
COLD FRONT WILL DROP SOUTHWARD THROUGH THE AREA...WITH ALL THE
MODELS SHOWING POST FRONTAL STRATUS TO MOVE BACK IN AROUND 00Z.
THUS WILL KEEP THE IFR CONDITIONS GOING THROUGH MUCH OF THE DAY
WITH A BRIEF BREAK THIS AFTERNOON BEFORE MVFR POST FRONTAL
CEILINGS MOVE IN.

NEXT QUESTION IS ON ANY POST FRONTAL PRECIPITATION CHANCES. 06.00Z
NAM AND GFS BOTH SHOWING SOME LIGHT PRECIPITATION. NAM IS THE
EARLIEST IN THE EVENING...WHILE THE GFS WOULD SUGGEST AFTER
MIDNIGHT. ONE CONCERN OF ANYTHING FALLING IN THE EVENING...IS THE
POTENTIAL LACK OF ICE CRYSTALS IN THE CLOUDS WHICH COULD RESULT IN
SOME PATCHY FREEZING DRIZZLE RATHER THAN FLURRIES. FOR NOW WILL
JUST MENTION FLURRIES...BUT THIS WILL HAVE TO BE MONITORED.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
340 PM CST SUN FEB 5 2012

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

&&

$$

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








AREA FORECAST DISCUSSION

NWS TALLAHASSEE FL

 320 AM EST Wed Feb 8 2012

.SYNOPSIS...
07Z water vapor and H4 RUC analysis continues to show a rather
complex upper level pattern across the CONUS this morning. REX block
configuration from 24 hours ago over the western portion of the
continent has broken down, with the closed upper low over Colorado
now having opened up and become progressive. This trough and any
significant associated forcing will pass north of our region today.
We continue to see an active southern stream flow with abundant
mid/upper level energy in the form of high level cirrus streaming
northward over the Gulf of Mexico.

At the surface, forecast area resides in a region of weak gradient
between 1035mb high pressure over the central Plains, and a surface
trough in place across the southern FL Peninsula/FL Straits.
Weak/subtle cold front is analyzed slowly approaching our area
across AL. This front is better defined above the surface, but
should at least result in a somewhat drier low level airmass in its
wake over the next couple of days. Regional radars do show a few
showers up into central AL/Northern GA in closer proximity to the
passing synoptic forcing. However as mentioned above, this
sufficient forcing will remain to our north and keep shower chances
out of our forecast.

&&

.SHORT TERM (TODAY THROUGH FRIDAY)...
Today,
Mid/Upper level shortwave passes from the TN valley this morning to
the mid-Atlantic coast this evening. Atmospheric momentum associated
with this energy will be enough to pass a weak cold frontal boundary
through the forecast area by mid/late afternoon. This will be an
uneventful frontal passage with only some clouds and a slight wind
shift to mark its arrival. Overall, will be a pleasant February day
with filtered sunshine and high temperatures ranging from the upper
60s north to the lower 70s south.

Tonight,
Dry and somewhat cooler night upcoming to what has been experienced
lately. The drier airmass will allow temperatures to fall into the
upper 30s to lower 40s for much of the area. The high center will
still be well to our NW keeping the gradient fairly tight. With this
in mind, don`t anticipate much chance of any normally sheltered
areas de-coupling and getting much colder than is currently
forecast. Therefore, temperatures and dewpoint depressions should
stay above the level of a frost threat.

Thursday/Thursday night,
Little change in the forecast with any significant northern stream
energy remaining well to our north. High level clouds will likely be
on the increase once again by the end of the day as southern stream
jet energy re-develops along the northern Gulf Coast. Plenty of dry
air in the lower levels will keep rain out of our forecast with high
temps reaching up into the 60s. Surface ridging will set up just to
our north Thursday night which will bring the potential for some mid
30s temps inland, and a resulting frost potential. However, some
uncertainly remains regarding the amount of mid/high level clouds
that will be overspreading the area. Impressive southern stream jet
energy suggest we will see the cirrus. Even high level cloudiness
can sometimes disrupt the radiative process and help keep temps
warmer than expected. This portion of the forecast will need to be
monitored closely for those with sensitive outdoor vegetation.

Friday,
Uncertainly is beginning to increase by the end of Friday with
regards to energy propagating across the southern Plains and
northern Gulf coast. GFS is showing a scenario in which much of this
energy is absorbed by a large cut-off low near the California Baja
region. ECMWF/Canadian are much more aggressive, and allow the
majority of this shortwave energy to bypass the upper low into the
southern Plains. These models offer solutions that are potentially
wetter for our western zones by Friday evening, and for all of our
zones Friday night. Tough call on this one, but out of respect for
the ECMWF will add slight chance PoPs to the grids beginning Friday
afternoon in the far west, and for all zones Friday night. Should
the ECMWF/Canadian solution be the correct trend, then these rain
chances would need to be adjusted upward in future forecast
packages.

&&

.LONG TERM (SATURDAY THROUGH NEXT WEDNESDAY)...
The complex and generally messy large scale pattern is expected to
remain so during the forecast period, while undergoing some
retrogression, with axis of the mean ridge over the western U.S.
shifting westward into the eastern Pacific, and the large polar
vortex over eastern Canada also evolving westward. The main effect
will be to broaden the mean trough westward across the CONUS,
resulting in a positive tilted trough axis across the Intermountain
West, and a nearly zonal flow eastward across the eastern half of
the country. The southern portion of the stream will remain quite
strong. A series of short waves will drop southward into the mean
trough axis over the Intermountain West, then weaken as they head
rapidly east or northeast across the eastern U.S. As always, the
devil is in the details when it comes to the forecast for he
Tri-State Area. The GFS and Euro continue to diverge predictably
towards the end of the period, in how they handle the short waves
dropping into the mean trough position. The Canadian and EURO are in
better agreement, showing more short wave energy in the southern
stream, which gives me some confidence, and a blend of the two
solutions seems the way to go. Friday night and Saturday short wave
energy will be moving eastward across the eastern U.S. pushing a
cold front well to the south across the southern Florida peninsula,
bringing at least a slight chance of rain, and a surge of colder
drier air behind it across the southeast U.S. Temperatures may drop
to near or a little below freezing in some areas on Monday morning.
Then expect a fairly rapid rebound in temperatures by mid week,
along with an increasing chance of rain, as the next short wave
rounds the bottom of the trough and heads northeast. Temperatures
will start out near normal on Saturday, then drop below normal
Sunday and Monday, then trend back to above normal by Wednesday.

&&

.MARINE
A weak cold front will cross the forecast area today. The gradient
behind this front will increase and result in near advisory level
northerly winds tonight through Thursday morning. A surface ridge
will slowly build down from the north later Thursday into Friday
which will act to drop winds and seas back down below headline
criteria. Another period of cautionary to advisory level northerly
flow looks to develop during the upcoming weekend.

&&

.AVIATION (THROUGH 06Z THURSDAY)...
VFR conditions  will continue across the Tri-State Area through the
forecast period and beyond, with patches of cirrus occasionally
streaming across the area. Although a drier airmass has spread into
the region, good nighttime cooling will result in temperatures
dropping to near the dew point temperatures in some areas, allowing
for the formation of some  mist before daybreak. The mist, in
combination with some lingering smoke, will produce patches of MVFR
visibilities primarily across south central Georgia before sunrise.

&&

.FIRE WEATHER...
Drier air is spreading across the Tri-State Area, and relative
humidities across inland portions of Florida will drop to at or
below 35 percent for several hours this afternoon, along with
relatively high dispersions. However, dispersions are not expected
to be quite high enough to warrant a Red Flag Watch or Warning, and
ERC values will continue relatively low. Thursday will remain dry,
with longer periods of critical relative humidity values, while
dispersions are expected to be a little lower. However, ERC values
are currently expected to remain below critical levels, so while
conditions for Thursday afternoon should be closely monitored, there
are no fire weather concerns at this time.

&&

.PRELIMINARY POINT TEMPS/POPS...
Tallahassee   72  39  66  36  70 /   0   0   0   0  10
Panama City   71  44  64  42  65 /   0   0   0   0  10
Dothan        68  40  62  38  66 /   0   0   0   0  10
Albany        69  38  63  35  67 /   0   0   0   0  10
Valdosta      71  39  65  39  70 /   0   0   0   0  10
Cross City    75  39  69  40  73 /   0   0   0   0  10
Apalachicola  70  42  64  41  65 /   0   0   0   0  10

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
AL...None.
GA...None.
FL...None.
GM...None.

&&

$$

SYNOPSIS/SHORT TERM/MARINE...MROCZKA
LONG TERM/AVIATION/FIRE WX...DUVAL





AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 327 AM EST WED FEB 8 2012

.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...AN UPPER DISTURBANCE WILL MOVE THROUGH CENTRAL INDIANA
OVERNIGHT AND EARLY WEDNESDAY MORNING BRINGING MEASURABLE SNOW TO
MUCH OF THE AREA FOR THE MORNING COMMUTE. BY WEDNESDAY AFTERNOON
HIGH PRESSURE RIDGING WILL BUILD INTO THE AREA AND BRING DRY WEATHER
UNTIL THE NEXT WAVE ARRIVES ON FRIDAY WITH MORE CHANCES FOR SNOW
THROUGH FRIDAY NIGHT. AFTER THAT THE WEATHER WILL BE QUIET UNTIL THE
NEXT WAVE APPROACHES FOR MONDAY NIGHT.

&&

.NEAR TERM /TONIGHT/...

RADAR MOSAICS CONTINUE TO INDICATE PRECIP CONTINUING TO DEVELOP
ACROSS SE MO AND SOUTHERN ILLINOIS PUSHING NORTHEAST. GIVEN THE
LACK OF ANY PRECIP OVER THE NEXT COUPLE OVER HOURS...HAVE REMOVED
POPS UNTIL AFTER MIDNIGHT. RUC FORECAST SOUNDINGS INDICATE
SATURATION THROUGH THE COLUMN AFTER 09Z. TIME HEIGHT SECTIONS SHOW
SATURATION CONTINUING THROUGH TE MORNING RUSH HOURS...THUS WILL
ISSUE ANOTHER SPS TO HIGHLIGHT THIS. BASED ON RUC AND TEMPS
EXPECTED TO APPROACH WET BULB TEMPS...HAVE TRENDED LOW TEMPS
WARMER.

&&

.SHORT TERM /WEDNESDAY AFTERNOON THROUGH FRIDAY/...

MODELS ARE IN GOOD AGREEMENT SO WILL USE A CONSENSUS APPROACH. THE
UPPER WAVE IS THROUGH THE AREA BY WEDNESDAY AFTERNOON WITH UPPER
RIDGING MOVING INTO THE AREA. THIS WILL KEEP THINGS DRY UNTIL FRIDAY
WHEN ANOTHER WAVE APPROACHES AND BRINGS LOW CHANCES FOR SNOW. FOR
TEMPERATURES GENERALLY WENT NEAR A GUIDANCE AVERAGE...BUT USED
TEMPERATURES COOLER THAN GUIDANCE FOR WEDNESDAY AND FRIDAY HIGHS
WITH COLD ADVECTION AND EXPECTED CLOUD COVER. THIS YIELDED
TEMPERATURES NEAR AVERAGE FOR THIS TIME OF YEAR.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

THE BEST CHANCES OF PRECIP WILL BE DURING THE FRIDAY NIGHT PERIOD AS
A STRONG UPPER TROUGH ROTATES EAST ACROSS THE GREAT LAKES AND AGAIN
TOWARDS MONDAY NIGHT WARM ADVECTION INCREASES AND A WEAK UPPER LEVEL
DISTURBANCE MOVES THROUGH THE OHIO VALLEY.

WENT PRETTY MUCH TO ALL BLEND POPS FRIDAY NIGHT.  BUT IN THE NORTH I
INCREASED THEM A LITTLE AS THERE COULD BE SOME LAKE ENHANCEMENT.
THIS LAKE ENHANCEMENT MAY LINGER INTO SATURDAY SO KEPT SLIGHT
CHANCES ACROSS MUCH OF OUR FAR NORTH.  MODELS HAVE TRENDED COLDER
OVER THE WEEKEND AND WENT CLOSER TO THE CONSALL NUMBERS AS THE COLD
UPPER TROUGH MOVES ACROSS THE GREAT LAKES OVER THE WEEKEND.

HIGH PRESSURE WILL MOVE ACROSS OUR REGION SUNDAY AND WARM ADVECTION
STARTS MONDAY.  MODELS HAVE TRENDED SLOWER...SO WILL ONLY MENTION
SLIGHT CHANCE OF PRECIP ACROSS OUR FAR SOUTHWEST LATE MONDAY.

MOST MODELS PRODUCE LIGHT PRECIP AMOUNTS AND THICKNESS SHOULD BE LOW
ENOUGH FOR MOSTLY SNOW NORTH AND CENTRAL MONDAY NIGHT.  RAISED
TEMPERATURES A LITTLE WITH CLOUDS AND WARM ADVECTION MONDAY NIGHT.
ALL BLEND TEMPERATURES MAY BE A TAD WARM TUESDAY AS THERE WILL BE
LOTS OF CLOUDS.  BUT ONLY CHANGE I MADE WAS TO LOWER THE NORTH HALF
A FEW DEGREES IN CASE THERE WAS SOME LEFT OVER SNOWFALL FROM MONDAY
NIGHT.

&&

.AVIATION /DISCUSSION FOR THE 080900Z TAF UPDATE/...

LIGHT SNOW EXPANDING INTO THE NORTHERN HALF OF THE FORECAST AREA
EARLY THIS MORNING. HAVE GONE AHEAD AND SHIFTED KIND TO 4SM WITH -SN
AS FLAKES ARE JUST BEGINNING TO FALL HERE AT WFO INDY. HAVE HELD IFR
CONDITIONS WITHIN A TEMPO GROUP FOR THE TIME BEING AS OB SITES
ACROSS EASTERN ILLINOIS HAVE CONFIRMED. MAY EVENTUALLY NEED TO MAKE
THIS A PREVAILING GROUP WITHIN THE NEXT COUPLE HOURS BUT WILL ADJUST
AS CONDITIONS EVOLVE. MADE ADJUSTMENTS TO KHUF AND KLAF TERMINALS AS
WELL BASED ON CURRENT RADAR ANALYSIS. KHUF HAS MANAGED TO STAY OUT
OF STEADIER SNOW SO FAR BUT THAT IS LIKELY TO CHANGES BY 09-0930Z.

06Z DISCUSSION FOLLOWS.

WEAK UPPER SYSTEM CURRENTLY MOVING INTO WESTERN ILLINOIS RESULTING
IN AREA OF IFR VISIBILITIES/CEILINGS IN LIGHT SNOW. SHORT TERM MODEL
DATA BRING THIS FEATURE ACROSS THE AREA DURING THE EARLY MORNING
HOURS ON WEDNESDAY. EXPECTING A PERIOD OF IFR CONDITIONS IN LIGHT
SNOW AT THE TAF SITES ROUGHLY 080900Z-081400Z. ONCE THIS FEATURE
PASSES...CEILINGS SHOULD SETTLE INTO THE MVFR CATEGORY 015-025
THROUGH 081800Z.

NO WIND ISSUES EXPECTED THROUGH 081800Z.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CP
NEAR TERM...PUMA
SHORT TERM...CP
LONG TERM....JH
AVIATION...JAS/RYAN

















AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 1135 PM EST TUE FEB 7 2012

.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...AN UPPER DISTURBANCE WILL MOVE THROUGH CENTRAL INDIANA
OVERNIGHT AND EARLY WEDNESDAY MORNING BRINGING MEASURABLE SNOW TO
MUCH OF THE AREA FOR THE MORNING COMMUTE. BY WEDNESDAY AFTERNOON
HIGH PRESSURE RIDGING WILL BUILD INTO THE AREA AND BRING DRY WEATHER
UNTIL THE NEXT WAVE ARRIVES ON FRIDAY WITH MORE CHANCES FOR SNOW
THROUGH FRIDAY NIGHT. AFTER THAT THE WEATHER WILL BE QUIET UNTIL THE
NEXT WAVE APPROACHES FOR MONDAY NIGHT.

&&

.NEAR TERM /TONIGHT/...

RADAR MOSAICS CONTINUE TO INDICATE PRECIP CONTINUING TO DEVELOP
ACROSS SE MO AND SOUTHERN ILLINOIS PUSHING NORTHEAST. GIVEN THE
LACK OF ANY PRECIP OVER THE NEXT COUPLE OVER HOURS...HAVE REMOVED
POPS UNTIL AFTER MIDNIGHT. RUC FORECAST SOUNDINGS INDICATE
SATURATION THROUGH THE COLUMN AFTER 09Z. TIME HEIGHT SECTIONS SHOW
SATURATION CONTINUING THROUGH TE MORNING RUSH HOURS...THUS WILL
ISSUE ANOTHER SPS TO HIGHLIGHT THIS. BASED ON RUC AND TEMPS
EXPECTED TO APPROACH WET BULB TEMPS...HAVE TRENDED LOW TEMPS
WARMER.

&&

.SHORT TERM /WEDNESDAY AFTERNOON THROUGH FRIDAY/...

MODELS ARE IN GOOD AGREEMENT SO WILL USE A CONSENSUS APPROACH. THE
UPPER WAVE IS THROUGH THE AREA BY WEDNESDAY AFTERNOON WITH UPPER
RIDGING MOVING INTO THE AREA. THIS WILL KEEP THINGS DRY UNTIL FRIDAY
WHEN ANOTHER WAVE APPROACHES AND BRINGS LOW CHANCES FOR SNOW. FOR
TEMPERATURES GENERALLY WENT NEAR A GUIDANCE AVERAGE...BUT USED
TEMPERATURES COOLER THAN GUIDANCE FOR WEDNESDAY AND FRIDAY HIGHS
WITH COLD ADVECTION AND EXPECTED CLOUD COVER. THIS YIELDED
TEMPERATURES NEAR AVERAGE FOR THIS TIME OF YEAR.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

THE BEST CHANCES OF PRECIP WILL BE DURING THE FRIDAY NIGHT PERIOD AS
A STRONG UPPER TROUGH ROTATES EAST ACROSS THE GREAT LAKES AND AGAIN
TOWARDS MONDAY NIGHT WARM ADVECTION INCREASES AND A WEAK UPPER LEVEL
DISTURBANCE MOVES THROUGH THE OHIO VALLEY.

WENT PRETTY MUCH TO ALL BLEND POPS FRIDAY NIGHT.  BUT IN THE NORTH I
INCREASED THEM A LITTLE AS THERE COULD BE SOME LAKE ENHANCEMENT.
THIS LAKE ENHANCEMENT MAY LINGER INTO SATURDAY SO KEPT SLIGHT
CHANCES ACROSS MUCH OF OUR FAR NORTH.  MODELS HAVE TRENDED COLDER
OVER THE WEEKEND AND WENT CLOSER TO THE CONSALL NUMBERS AS THE COLD
UPPER TROUGH MOVES ACROSS THE GREAT LAKES OVER THE WEEKEND.

HIGH PRESSURE WILL MOVE ACROSS OUR REGION SUNDAY AND WARM ADVECTION
STARTS MONDAY.  MODELS HAVE TRENDED SLOWER...SO WILL ONLY MENTION
SLIGHT CHANCE OF PRECIP ACROSS OUR FAR SOUTHWEST LATE MONDAY.

MOST MODELS PRODUCE LIGHT PRECIP AMOUNTS AND THICKNESS SHOULD BE LOW
ENOUGH FOR MOSTLY SNOW NORTH AND CENTRAL MONDAY NIGHT.  RAISED
TEMPERATURES A LITTLE WITH CLOUDS AND WARM ADVECTION MONDAY NIGHT.
ALL BLEND TEMPERATURES MAY BE A TAD WARM TUESDAY AS THERE WILL BE
LOTS OF CLOUDS.  BUT ONLY CHANGE I MADE WAS TO LOWER THE NORTH HALF
A FEW DEGREES IN CASE THERE WAS SOME LEFT OVER SNOWFALL FROM MONDAY
NIGHT.

&&

.AVIATION /DISCUSSION FOR THE 080600Z TAFS/...

WEAK UPPER SYSTEM CURRENTLY MOVING INTO WESTERN ILLINOIS RESULTING
IN AREA OF IFR VISIBILITIES/CEILINGS IN LIGHT SNOW. SHORT TERM MODEL
DATA BRING THIS FEATURE ACROSS THE AREA DURING THE EARLY MORNING
HOURS ON WEDNESDAY. EXPECTING A PERIOD OF IFR CONDITIONS IN LIGHT
SNOW AT THE TAF SITES ROUGHLY 080900Z-081400Z. ONCE THIS FEATURE
PASSES...CEILINGS SHOULD SETTLE INTO THE MVFR CATEGORY 015-025
THROUGH 081800Z.

NO WIND ISSUES EXPECTED THROUGH 081800Z.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CP
NEAR TERM...PUMA
SHORT TERM...CP
LONG TERM....JH
AVIATION...JAS











AREA FORECAST DISCUSSION

NWS TOPEKA KS

 321 AM CST WED FEB 8 2012

...ARCTIC AIR TO INTRUDE ON THE REGION THIS WEEKEND...

.DISCUSSION...
09Z WATER VAPOR SHOWS SEVERAL SHORTWAVE WITH ONE MOVING EAST OF THE
FORECAST AREA...A SECOND CLOSED CIRCULATION OVER MT...AND A THIRD
WAVE OFF THE SOUTHERN CA COAST. MEANWHILE SFC OBS SHOW A COLD SFC
RIDGE OF HIGH PRESSURE NOSING INTO CENTRAL KS.

FOR TODAY THROUGH THURSDAY...THE FORECAST AREA SHOULD REMAIN UNDER
THE INFLUENCE OF NORTHWEST FLOW WITH THE WAVE OVER MT EVENTUALLY
SHEARING OUT AND MOVING TO THE EAST. THE SFC RIDGE BUILDING INTO
CENTRAL KS NOW WILL LIMIT ANY DEEP MOISTURE SO THE FORECAST REMAINS
DRY. THE MOST UNCERTAIN PART OF THE FORECAST IS WITH THE LOW CLOUDS.
THE NAM AND RUC ARE SUGGESTING THE STRATUS COULD HANG AROUND FOR A
GOOD CHUNK OF THE DAY. SO WITH MOSTLY CLOUDY TO OVERCAST SKIES AND
CONTINUED COLD AIR ADVECTION...TODAY`S HIGHS WILL NOT WARM UP MUCH.
WE SHOULD SEE SOME RETURN FLOW AND SUNSHINE FOR THURSDAY AS THE SFC
RIDGE MOVES EAST OF THE AREA. THIS SHOULD ALLOW FOR HIGHS TO WARM
INTO THE 40S.

THURSDAY NIGHT WILL SEE PERHAPS THE STRONGEST COLD FRONT IN TERMS OF
COLD AIR SO FAR THIS WINTER...AS AN ARCTIC AIRMASS BUILDS SOUTH
THROUGH THE PLAINS FOR FRIDAY AND SATURDAY. THE MODEL CONSENSUS IS
FOR STRONG COLD AIR ADVECTION TO OCCUR BEHIND THE FRONT THROUGH
SATURDAY. TO MAKE THINGS WORSE...THE COLD AIR WILL BE MOVING OVER
THE SNOWPACK ACROSS CENTRAL NEB. SO HAVE LOWERED TEMPS FOR FRIDAY
AND SATURDAY. TEMPS ON SATURDAY ARE NOT EXPECTED TO MAKE IT OUT OF
THE 20S. THE MODELS ARE SHOWING SOME MID LEVEL FRONTOGENESIS ON THE
WESTERN EDGE OF THE UPPER TROUGH FOR FRIDAY NIGHT AND SATURDAY. THIS
FRONTOGENESIS IS COINCIDENTAL WITH A NARROW AXIS OF MID LEVEL
MOISTURE. THE GFS AND ECMWF TEND TO KEEP THIS BAND JUST TO THE WEST
OF THE FORECAST AREA SO HAVE NOT INCLUDED ANY POPS AT THIS TIME.
HOWEVER WILL MENTION A SLIGHT CHANCE FOR SOME FLURRIES IN PARTS OF
NORTH CENTRAL KS ON SATURDAY.

THE MAKINGS OF A WINTER STORM APPEAR TO BE COMING TOGETHER FOR
SUNDAY NIGHT INTO MONDAY MORNING. THE MEDIUM RANGE MODELS ARE IN
REASONABLE AGREEMENT THAT A SHORTWAVE WILL MOVE FROM THE PACIFIC
INTO THE PLAINS AS THE HIGH AMPLITUDE UPPER RIDGE OVER THE WEST
COAST BREAKS DOWN. BUFKIT SOUNDINGS SHOW THE COLUMN SATURATING WITH
ANY WARM NOSE DUE TO WARM AIR ADVECTION SUNDAY NIGHT INCREASING TO
ONLY ABOUT +1C. THIS SHOULD NOT BE ENOUGH TO MELT ANY SNOW
COMPLETELY...AND THINK THE PREDOMINANT PRECIP TYPE SHOULD BE SNOW.
HOWEVER THE MID LEVEL WARM AIR ADVECTION SHOULD BRING PLENTY OF
MOISTURE TO GO ALONG WITH THE REASONABLE FORCING OF THE UPPER WAVE.
BECAUSE OF THIS HAVE INCREASED POPS FOR SUNDAY NIGHT AND MONDAY. QPF
FORECASTS FROM THE ECMWF AND GFS SUGGEST THAT THERE COULD BE A
COUPLE INCHES OF SNOW...WHICH IS IN LINE WITH THE MODEST FORCING
PROVIDED BY THE OPEN WAVE. IF PRECIP HANGS ON LONG ENOUGH INTO THE
DAY MONDAY...WARM AIR ADVECTION MAY BE STRONG ENOUGH TO CAUSE THE
PRECIP TO CHANGE OVER TO LIQUID BY MONDAY AFTERNOON. WHILE THINGS
ARE FAR FROM CERTAIN...THIS SYSTEM BARES WATCHING AS IT GETS CLOSER.

THE MODELS PROG AN ACTIVE WEATHER PATTERN FOR NEXT WEEK AS A SECOND
WAVE LIFTS OUT INTO THE PLAINS ON TUESDAY. THERE SEEMS TO BE SOME
AGREEMENT IN THE TIMING OF THIS SECOND WAVE. ALTHOUGH THERE IS SOME
DISAGREEMENT IN THE TRACK OF THIS WAVE. REGARDLESS BOTH MODELS...
ESPECIALLY THE ECMWF WITH ITS NORTHERN TRACK...BRING ENOUGH WARM AIR
NORTH INTO EASTERN KS THAT PRECIP SHOULD BE ALL RAIN. IF THE SYSTEM
IS ABLE TO BRING ENOUGH WARM AIR NORTH...THERE COULD EVEN BE ENOUGH
INSTABILITY FOR SOME CONVECTION. AGAIN THIS WILL NEED TO BE WATCHED
IN LATER RUNS. AT THIS POINT...THE FORECAST HAS MODERATING TEMPS
INTO TUESDAY WITH A CHANCE FOR SOME RAIN.

WOLTERS

&&

.AVIATION...
CEILING HEIGHTS ARE THE MAIN CHALLENGE FOR THIS FORECAST. HEIGHTS
LIKELY TO BE ON THE IFR/MVFR THRESHOLD THROUGH 12Z. SINKING MOTION
BEHIND UPPER TROF AND BUILDING LOW LEVEL HIGH PRESSURE TO COUNTERACT
WET LOW LEVELS AIDED BY EVENING PRECIPITATION. WILL TEMPO IFR LEVELS
FOR THE FIRST FEW HOURS...BUT MODELS SUGGEST THE FORMER PROCESS
SHOULD TAKE OVER THEREAFTER. TRANSITION FROM MVFR TO VFR CONDITIONS
ALSO UNCERTAIN...BUT LATEST PROGS QUICKER AND WILL TREND THAT WAY.

65

&&

.TOP WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$






AREA FORECAST DISCUSSION

NWS GOODLAND KS

 951 PM MST TUE FEB 7 2012

.UPDATE...
741 PM MST TUE FEB 7 2012

JUST COMPLETED AN UPDATE. SATELLITE SHOWING CLOUD COVER IS SLOW TO
ERODE. AREA 00Z SOUNDINGS SHOW A STRONG INVERSION WITH WARMING
ALOFT EXPECTED DURING THE NIGHT. SO SLOWED THE CLEARING PROCESS
AND WARMED MINS ACCORDINGLY BASED ON REALITY AND LATEST MODEL
TRENDS. RUC LOOKS TO BE HANDLING THE BOUNDARY LAYER RH THE BEST AT
THIS TIME. ALSO BASED ON THE 00Z SOUNDINGS AND LATEST
RUC...HRRR...AND NAM SHOWING REDUCED VISIBILITIES IN THE SAME
PLACE...DECIDED TO ADD PATCHY FREEZING FOG INTO THE NORTHWEST HALF
TO TWO-THIRDS.

BULLER
&&

.DISCUSSION...
245 PM MST TUE FEB 7 2012

TONIGHT...PRIMARY FORECAST CONCERN WILL BE HOW COLD OVERNIGHT LOW
TEMPERATURES WILL DROP AND HOW QUICKLY CLOUDS WILL CLEAR THIS
EVENING...AND THE DEVELOPMENT OF FOG. IF CLOUDS LINGER OR FOG
DEVELOPS ACROSS THE AREA...CURRENT OVERNIGHT LOW TEMPERATURES MAY BE
TOO COLD. IF SKIES CLEAR COMPLETELY ALLOWING FOR MAXIMUM RADIATIONAL
COOLING...TEMPERATURES MAY BE TOO WARM.

CURRENT WV SATELLITE IMAGERY SHOWS UPPER LEVEL TROUGH MOVING ACROSS
THE CENTRAL CONUS WITH A SURGE OF COLD AIR MOVING DOWN OUT OF CANADA
INTO THE NORTHERN PLAINS. A FEW FLURRIES MAY STILL BE POSSIBLE LATE
THIS AFTERNOON BUT WILL END BY THIS EVENING. SUBSIDENCE WILL QUICKLY
MOVE INTO WESTERN AND CENTRAL KANSAS OVERNIGHT BEHIND THE DEPARTING
SYSTEM...DROPPING TEMPERATURES INTO THE SINGLE DIGITS ACROSS ALL BUT
THE SOUTHERN PERIPHERY OF THE CWA. GIVEN LIGHT WINDS AND SUFFICIENT
LOW LEVEL MOISTURE...THERE IS A CHANCE OF PATCHY FOG DEVELOPING
ACROSS AT LEAST THE NORTHERN HALF OF THE CWA. HOWEVER...CONFIDENCE
NOT HIGH ENOUGH WITH CURRENT CLOUD COVER SLOW TO EXIT AND MAY LIMIT
RADIATIONAL COOLING.

PMM

WEDNESDAY-FRIDAY...DRY WITH WARMING TEMPERATURES WEDNESDAY AND
THURSDAY. A BACKDOOR FRONT MOVES IN FROM THE NORTH/NORTHEAST
FRIDAY LEADING TO COLDER TEMPERATURES...ESPECIALLY ACROSS THE
EAST/NORTHEAST. OVERNIGHT LOWS WILL CONTINUE TO BE COLD IN SNOW
PACK AREAS WHERE SINGLE DIGITS EXPECTED...FURTHER SOUTH OUT OF THE
SNOW PACK TEENS TO LOW 20S EXPECTED.

FRIDAY NIGHT-SATURDAY...UPPER LEVEL DISTURBANCE AIDED BY
FAVORABLE POSITION TO JET STREAK MOVES INTO THE AREA WITH BEST
MOISTURE AND LIFT FAVORING THE NORTHEAST 1/2-1/3 OF THE AREA FOR
SOME LIGHT SNOW. HIGH TEMPERATURES GENERALLY IN THE 30S...WARMEST
ACROSS THE SOUTHWEST PART OF THE AREA.

SATURDAY NIGHT-SUNDAY NIGHT...UPPER TROUGH MOVES ACROSS THE AREA
DURING THE PERIOD PRODUCING SOME SNOW. DIFFERENCES IN THE SPEED
AND INTENSITY OF THE TROUGH PREVENT GETTING TOO DETAILED AT
PRESENT TIME BUT CANT RULE OUT SOME ACCUMULATING SNOW. BEST TIME
WOULD BE SUNDAY-SUNDAY NIGHT. HIGH TEMPERATURES SUNDAY IN THE 30S.

MONDAY...SHOULD SEE A DRY DAY WITH HIGHS IN THE UPPER 30S TO MID
40S (EAST TO WEST). HOWEVER...POSSIBLE SNOW COVER FROM SATURDAY
NIGHT-SUNDAY NIGHT SYSTEM COULD MAKE CURRENT FORECAST HIGHS
OPTIMISTIC.

MONDAY NIGHT-TUESDAY...ANOTHER IN A SERIES OF UPPER LOWS/TROUGHS
MOVES ACROSS THE AREA. LIGHT RAIN AND/OR LIGHT SNOW EXPECTED.

007
&&

.AVIATION...
951 PM MST TUE FEB 7 2012

FOR THE 06Z TAFS...CONCERNS FOR THIS PERIOD WILL BE CIGS/VIS AT
BOTH LOCATIONS. CURRENTLY...WIDESPREAD STRATUS HAS BLANKETED THE
AREA. FOR KGLD...BELIEVE BACK EDGE OF STRATUS WILL CLEAR TERMINAL
BRIEFLY ALLOWING TEMPERATURES TO FALL. THIS WILL ALLOW CIGS TO
REDEVLOP AT THE TERMINAL WHICH WILL BE IN THE IFR RANGE. THESE
CIGS WILL LIFT THROUGH THE MORNING HOURS AND SCATTER OUT BY EARLY
AFTERNOON. FOR KMCK...TERMINAL WILL STAY UNDER MVFR CIGS THROUGH
THE NIGHT AND INTO THE DAY ON WEDNESDAY. WINDS WILL SWITCH TO THE
SOUTH AT BOTH LOCATIONS AS SURFACE HIGH PRESSURE MOVES OFF TO THE
EAST.

BAS
&&

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

$$








AREA FORECAST DISCUSSION

NWS OMAHA/VALLEY NE

 316 AM CST WED FEB 8 2012

.DISCUSSION...

SFC HIGH PRESSURE CONTINUES TO MOVE SOUTH OVER THE FORECAST AREA
THIS MORNING WHILE LOW CLOUDS LINGER OVERHEAD. DIFFICULT TO GET A
GOOD HANDLE ON HOW QUICKLY/SLOWLY THE STRATUS DECK WILL ERODE. SOME
CLEARING HAS TAKEN PLACE OVER THE NORTHERN CWA AND ACROSS THE
MISSOURI RIVER VALLEY...HOWEVER THIS HAS BEEN A GENERALLY SLOW
PROCESS THIS MORNING. LATEST RUC AND HRRR MODEL RUNS SHOW SLOW SOUTHWARD
CLEARING SO WL KEEP MOSTLY CLOUDY GOING IN THE SOUTH WITH PARTLY
CLOUDY IN OUR NORTH FOR THE FIRST HALF OF THE DAY. IN THE UPPER
LEVELS...A PIECE OF ENERGY OVER EASTERN MONTANA WILL CONTINUE TO
MOVE SOUTHEAST TOWARD THE FORECAST AREA BY TONIGHT. FORCING
REMAINS VERY WEAK AND MOISTURE IS LIMITED SO NO MENTION OF
FLURRIES OR LIGHT SNOW WITH THE PASSAGE OF THIS WAVE.

WEAK WARM AIR ADVECTION SETS UP ON THURSDAY IN RETURN FLOW
REGIME...PROVIDING A BRIEF WARM UP INTO THE LOWER TO MID 30S. A
STRONG PUSH OF COLD AIR WILL SPREAD SOUTH ACROSS THE NRN PLAINS AND
INTO THE MIDWEST BY THURSDAY NIGHT IN ASSOCIATION WILL UPPER
TROF DIGGING ACROSS EASTERN CANADA. THE COLDER TEMPS WL CONTINUE
THROUGH THE WEEKEND WITH THE COLDEST OF THE DAYS ON SATURDAY. HIGHS
OVER THE SNOW COVER WILL LIKELY STRUGGLE TO WARM ABOVE THE UPPER
TEENS.

SFC HIGH PRESSURE BUILDS OVER THE CWA ONCE AGAIN ON SUNDAY WITH
STRONG WARM AIR ADVECTION RETURNING SUNDAY NIGHT. MEDIUM RANGE
MODELS IN GOOD AGREEMENT ON MOVING A SHORTWAVE TROF THRU THE FOUR
CORNERS REGION SUNDAY NIGHT AND INTO THE CENTRAL PLAINS BY MONDAY
MORNING. FORCING AHEAD OF THIS WAVE SHOULD ALLOW SNOW TO DEVELOP
SUNDAY NIGHT INTO MONDAY ACROSS MUCH OF THE SOUTHERN FORECAST
AREA.

YET ANOTHER WAVE IS PROGGED TO MOVE INTO THE CNTRL PLAINS FOR MID
WEEK. MODELS KEEP GETTING A BIT STRONGER WITH THIS SYSTEM AND
CONTINUE TO CLOSE IT OFF AS IT MOVES INTO THE CNTRL PLAINS.

KERN

&&

.AVIATION...

06Z TAFS FOR KOMA...KLNK...KOFK.

BAND OF LIGHT SNOW SHIFTED SOUTH OF KOMA EARLIER THIS EVENING AND
SHOULD STAY MOSTLY SOUTHEAST OF KLNK. LOW CLOUDS CONTINUED TO
SLOWLY DECREASE IN THE FAR NORTHERN PARTS OF NORTHEAST NEBRASKA
AS OF 05Z...BUT REMAINED IN PLACE FOR MOST OF THE AREA.

CONFIDENCE IN TAF FORECASTS REMAINS LOW...DUE TO UNCERTAINTY WITH
LOW LEVEL MOISTURE SHOWN BY THE 00Z MODELS AND THE AFFECTS OF
CURRENT SNOW COVER. GENERALLY TRIED TO FOLLOW NAM 925 MB RH PROGS
TO TIME CEILINGS. LOW CLOUDS ARE EXPECTED TO DECREASE LATER
TONIGHT OR EARLY WEDNESDAY MORNING AT KOFK AND KOMA...BUT MAY NOT
MOVE OUT AROUND KLNK. RIDGE OF HIGH PRESSURE AT THE SURFACE FROM
THE EASTERN DAKOTAS INTO THE TEXAS PANHANDLE WILL CONTINUE TO
BUILD SOUTHWARD AND LOW LEVEL WINDS SHOULD BECOME WEST OR
SOUTHWEST BY WEDNESDAY AFTERNOON. THIS MAY ALLOW CLOUDS TO MOVE
BACK IN FOR KOFK AND KOMA WEDNESDAY AFTERNOON OR EVENING.

MILLER

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&

$$




AREA FORECAST DISCUSSION

NWS WILMINGTON NC

 321 AM EST WED FEB 8 2012

.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH LATER TODAY. HIGH PRESSURE WILL
BUILD IN THROUGH THURSDAY AND WILL WEAKEN ON FRIDAY. A STRONG COLD
FRONT WILL MOVE ACROSS THE AREA SATURDAY. ARCTIC AIR MASS WILL
SETTLE IN FOR THE LATTER HALF OF THE WEEKEND AS HIGH PRESSURE
BUILDS IN. COLD AND DRY HIGH PRESSURE WILL MOVE EAST OVER THE AREA
THROUGH MONDAY SHIFTING OFF SHORE BY TUESDAY ALLOWING FOR A
WARMING TREND TO BEGIN BY MID WEEK NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM WEDNESDAY...HIGH PRESSURE OVER THE CENTRAL PLAINS
CONTROLS THE WEATHER OVER THE EASTERN 2/3RDS OF THE NATION. WEAK LOW
PRESSURE IS ATTEMPTING TO ORGANIZE OFF THE SOUTHEAST COAST WITHIN A
LOW-LEVEL BAROCLINIC ZONE. THE CAROLINAS ARE CURRENTLY WITHIN A
WEAK PRESSURE GRADIENT EXTENDING NORTHWEST FROM THE LOW OFFSHORE
TOWARD AN UPPER LEVEL DISTURBANCE OVER THE MID-MISSISSIPPI VALLEY.
THE UPPER DISTURBANCE WILL PASS EAST THROUGH VIRGINIA THIS AFTERNOON
AND OFFSHORE THIS EVENING.

THERE WILL BE NO LOW-LEVEL MOISTURE TO SPEAK OF INVOLVED WITH THIS
SYSTEM...HOWEVER THE GFS SHOWS AN IMPRESSIVE SLUG OF 400-250 MB
MOISTURE CROSSING THE AREA LATER THIS MORNING THROUGH THE AFTERNOON
HOURS. THIS SHOULD LEAD TO CIRRUS CLOUD COVER PERHAPS NOT QUITE AS
THICK AND OPAQUE AS OBSERVED YESTERDAY. THERE MAY ALSO BE A SEVERAL-
HOUR LONG PERIOD OF ALTOCUMULUS AROUND MIDDAY ASSOCIATED WITH A
SHALLOW AND TRANSIENT AREA OF MOISTURE AT THE 700 MB LEVEL. ALL THIS
POTENTIAL FOR CLOUD COVER ARGUES FOR HIGH TEMPERATURES CLOSER TO THE
COOLER GFS NUMBERS TODAY...UPPER 50S TO AROUND 60 AREA-WIDE EXCEPT
FOR SOME LOWER 60S IN THE KINGSTREE/GEORGETOWN CORRIDOR. THE COOLER
GFS NUMBERS WORKED OUT MUCH BETTER WITH YESTERDAY`S CIRRUS CANOPY.

AS THE UPPER DISTURBANCE PUSHES THROUGH VIRGINIA THIS AFTERNOON A
SURFACE COLD FRONT WILL PUSH SOUTHEAST THROUGH OUR AREA. MODEST COLD
ADVECTION BEHIND THE FRONT WILL CONTINUE THROUGH THE NIGHT WITH
CLEARING SKIES. LOWS SHOULD REACH THE MID 30S MOST AREAS WITH SOME
UPPER 30S AT THE IMMEDIATE COAST.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM TUESDAY...HIGH PRESSURE WILL BUILD IN THROUGH THURSDAY
AS HIGH SHIFTS DOWN OVER THE LOWER MISSISSIPPI VALLEY WITH COOL
AND DRY AIR MOVING IN. BY FRI THE HIGH WEAKENS AND A DEEPER
RETURN FLOW SETS UP AS MID TO UPPER TROUGH BEGINS TO DIG DOWN OVER
THE CONUS PUSHING A NORTHERN STREAM COLD FRONT EAST AND EXTENDING
DOWN INTO THE CAROLINAS BY THE END OF THE PERIOD. OVERALL DRY AIR
MASS IN PLACE WITH PCP WATER VALUES DOWN LOWER THAN A HALF INCH
BUT WILL SEE A SLIGHT RISE IN MOISTURE IN THE RETURN FLOW ON FRI.
BY FRI EVENING VALUES WILL REACH UP NEAR .75 INCHES. NOT EXPECTING
ANY PCP WITH ONLY SOME HIGH CLOUDS AT TIMES.

WINDS WILL BEGIN TO BACK SLOWLY THROUGH THURS INTO FRIDAY. BEST
CAA WILL SHUT OFF THURS MORNING AND 850 TEMPS SHOWING A MINIMAL
RISE THROUGH FRI. WITH VERY WEAK GRADIENT ON THURS NIGHT SHOULD
SEE DECENT RADIATIONAL COOLING ALTHOUGH THERE WILL BE SOME HIGH
CLOUDS PASSING OVERHEAD. OVERNIGHT LOWS WILL BE DOWN AROUND
FREEZING. EXPECT HIGHS ON THURS TO ONLY REACH THE MID 50S BUT
READINGS SHOULD BE UP AROUND 60 BY FRI AFTN.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...COLD FRONT WILL SWEEP ACROSS AREA SAT
MORNING AS MID TO UPPER TROUGH DIGS DOWN INTO THE SOUTHEAST WHILE
MOVING EAST. A DEEP N-NW FLOW WILL SET UP BY SUNDAY AS MID TO
UPPER TROUGH AXIS SWINGS OFF THE COAST AS HIGH PRESSURE BUILDS IN
THROUGH THE REMAINDER OF THE WEEKEND. WILL TAP INTO MUCH COOLER
AND DRIER AIR MASS BY SUN AS 850 TEMPS DROP OUT FROM UP AROUND 4 C
SAT MORNING DOWN BELOW -5 C THROUGH SUN MORNING. HIGH TEMPS ON
SUNDAY WILL NOT MAKE IT OUT OF THE 40S ACROSS MOST PLACES AS
DEWPOINT TEMPS DROP DOWN INTO THE TEENS UNDER FULL SUNSHINE.
ALTHOUGH MAX CAA WILL END ON SUNDAY...BETTER RADIATIONAL COOLING
CONDITIONS SUNDAY NIGHT WILL BRING OVERNIGHT LOWS DOWN INTO THE
20S AND MAY EVEN REACH DOWN INTO THE TEENS IN TRADITIONALLY COOLER
SPOTS. WITH A COOL START MONDAY TEMPS WILL REBOUND UP NEAR 50
UNDER SUNNY SKIES AS NEUTRAL TO WEAK WAA BEGINS.

AS HIGH SHIFTS NEARLY OVERHEAD MON NIGHT AND THEN JUST OFF SHORE
BY TUES MORNING...EXPECT ANOTHER COLD NIGHT WITH IDEAL RADIATIONAL
COOLING EVEN THOUGH WEAK WAA WILL SET UP BY MORNING. SHOULD SEE
OVERNIGHT LOWS BELOW FREEZING ONCE AGAIN AS MOISTURE BEGINS TO
CREEP BACK UP. WARMING TREND WILL CONTINUE THROUGH MID WEEK AS
HIGH CONTINUES TO MOVE FURTHER OFF SHORE AND A DEEPER SOUTHERLY
RETURN FLOW SET UP.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 06Z...CLR SKIES EXPECTED EARLY THIS MORNING PERHAPS SOME
INCREASING THIN CIRRUS TOWARDS SUNRISE. GOOD RADIATIONAL
COOLING IS NOW OCCURRING WITH TEMPERATURE/DEWPOINT SPREADS
NARROWING. FORECAST NAM BUFR SOUNDING PROFILES CONTINUE TO SHOW
FAVORABLE PROFILES FOR FOG...BUT RUC PROFILES ARE MUCH DRIER IN THE
LOWEST 1000 FEET WHICH WOULD BE UNSUPPORTIVE OF IFR VSBYS. MOISTURE
IS LIMITED AND VERY SHALLOW BUT VERY DRY AIR IS NOTED ABOVE THE
INVERSION. NUMERICAL GUIDANCE INDICATES CALM SFC WINDS THROUGH
SUNRISE WITH VFR VISIBILITIES. CONFIDENCE IN SHALLOW GROUND FOG
DEVELOPMENT HAS INCREASED...THUS EXPECT MVFR VISIBILITIES TO DEVELOP
AT ALL TERMINALS THIS MORNING. THERE IS LOW CONFIDENCE THAT AT THE
LBT AND CRE TERMINALS IFR VISIBILITY COULD DEVELOP MAINLY AFTER
09Z...BUT FOR NOW THIS POTENTIAL IS NOT EXPLICIT IN THE FORECAST.

AFTER SUNRISE EXPECT INCREASING MID-LEVEL CLOUDS AT FLO/LBT AND BY
MID-MORNING AT THE COASTAL TERMINALS. LIGHT NORTHEAST WINDS WILL
BECOME WEST-NORTHWEST MID-LATE MORNING AT FLO/LBT AND AT THE COASTAL
TERMINALS IN THE AFTERNOON AS A SURFACE TROUGH MOVES THROUGH.

EXTENDED OUTLOOK...LOW CONFIDENCE FOR IFR/MORNING FOG FRIDAY. SLIGHT
CHANCE RAIN SATURDAY. OTHERWISE VFR.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM WEDNESDAY...WEAK LOW PRESSURE IS ATTEMPTING TO ORGANIZE
OFF THE FLORIDA EAST COAST THIS MORNING...WHILE SPRAWLING HIGH
PRESSURE OVER THE MID-SECTION OF THE NATION SLOWLY MOVES EAST. A DRY
COLD FRONT JUST WEST OF THE APPALACHIANS WILL MOVE EAST AND ACROSS
THE WATERS THIS AFTERNOON...TURNING OUR LIGHT NORTH TO NORTHEAST
WINDS NORTHWESTERLY. THE FLORIDA LOW WILL LINK UP WITH THIS FRONT
AND SHOOT NORTHEAST AND OUT OF SEA LATER TODAY. OUR WIND SPEEDS WILL
SURGE TO A SOLID 15 KNOTS TONIGHT WITH SOME GUSTS TO 20 KNOTS
POSSIBLE. SEAS ARE CURRENTLY ONLY 2-3 FEET WITH THE MAJORITY OF THE
WAVE ENERGY AN EASTERLY SWELL. SHORT-PERIOD WAVES WILL INCREASE
TONIGHT WITH THE STRONGER OFFSHORE FLOW DEVELOPING...WITH SEAS
BUILDING T0 3-4 FT 10-20 MILES FROM SHORE.

SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM TUESDAY...HIGH PRESSURE WILL BUILD IN ON THURS BUT WILL
WEAKEN LATE THURS THROUGH FRIDAY BEFORE MID TO UPPER TROUGH DIGS
DOWN INTO THE CONUS DRAGGING A STRONG COLD FRONT TOWARD WATERS BY
END OF THE PERIOD. WILL SEE DIMINISHING OFF SHORE FLOW AS CAA ENDS
EARLY THURS. N-NW WINDS UP AROUND 15 KTS WILL QUICKLY DIMINISH
THROUGH THURS MORNING. WINDS WILL BECOME VERY LIGHT AS HIGH
PRESSURE WEAKENS THROUGH THURS NIGHT BUT WILL EVENTUALLY PICK UP
AGAIN ON FRI AS RETURN FLOW SETS UP AHEAD OF NEXT SYSTEM. BY FRI
NIGHT SOUTHERLY WINDS WILL INCREASE UP NEAR 15 KTS AND WILL
INCREASE FURTHER AS BEFORE THEY VEER AROUND THROUGH SAT MORNING AS
COLD FRONT APPROACHES THE WATERS FROM THE WEST. SEAS AROUND 2 TO 3
FT TO START WILL DROP DOWN TO 1 TO 2 FT THROUGH EARLY FRI. AS
RETURN FLOW INCREASES THROUGH FRI NIGHT...SEAS WILL INCREASE UP TO
2 TO 4 FT BY END OF PERIOD.

LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...
WINDS WILL INCREASE AS THEY VEER AROUND TO THE W-NW IN TIGHTENED
GRADIENT FLOW AS COLD FRONT MOVES THROUGH SAT. EXPECT WINDS UP
AROUND NEAR 15 TO 20 KTS AS COLD FRONT MOVES THROUGH AND THEN
SHOULD SEE A BIT OF DROP BEFORE MAJOR COLD SURGE SAT NIGHT INTO
SUNDAY WITH NORTHERLY WINDS INCREASING UP TO 25 KTS. THESE STRONG
NORTHERLY WINDS WILL DRIVE SEAS UP TO 4 TO 6 FT THROUGH SUN
MORNING. LATEST WNA SHOW SEAS WINDS AND SEAS REACHING SCA
THRESHOLDS FOR A FEW HOURS EARLY SUNDAY. AS CAA CUTS OFF AND
GRADIENT WEAKENS THROUGH LATE SUNDAY...WINDS WILL DIMINISH TO 10
TO 15 KTS AS THEY VEER SLOWLY AROUND TO THE N-NE BY MONDAY
MORNING. SEAS WILL DROP DOWN TO 3 FT OR LESS BY MONDAY MORNING.

&&

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

&&

$$

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









AREA FORECAST DISCUSSION

NWS WILMINGTON NC

 1230 AM EST WED FEB 8 2012

.SYNOPSIS...
HIGH PRESSURE WILL BUILD FROM THE WEST FOR MUCH OF THE
WEEK...KEEPING CONDITIONS DRY WITH TEMPERATURES NEAR NORMAL FOR THIS
TIME OF THE YEAR. A STRONG COLD FRONT WILL MOVE ACROSS THE AREA
SATURDAY...WITH MUCH COOLER CONDITIONS EXPECTED INTO EARLY NEXT
WEEK.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS OF 1230 AM WEDNESDAY...CLEAR SKIES AND CALM WINDS ACROSS THE AREA
HAVE LED US TO LOWER THE LOW TEMPERATURE FORECASTS BY 1-3 DEGREES
FOR THE REMAINDER OF THE OVERNIGHT PERIOD. LOWER TO MID 30S ARE
EXPECTED INLAND...WITH UPPER 30S TO LOWER 40S AT THE IMMEDIATE
COAST. RADIATIONAL COOLING CONDITIONS ARE VERY GOOD CURRENTLY AND
INCREASING HIGH THIN CIRRUS LATE WILL DO LITTLE TO OFFSET THAT.
THERE IS SOME POTENTIAL FOR SHALLOW GROUND FOG TO DEVELOP BUT IT
APPEARS TOO ISOLATED AT THIS TIME FOR INCLUSION IN THE FORECAST.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
AS OF 3 PM MONDAY...HIGH PRESSURE WILL BE THE MAIN THEME OF THE
SHORT TERM PERIOD. WEAK HIGH PRESSURE IN PLACE WED WILL BE PUSHED
EAST AS A FAIRLY IMPRESSIVE SHORTWAVE PASSES NORTH OF THE AREA LATER
TOMORROW. DRY COLD FRONT EXTENDING SOUTH THE SURFACE WAVE ASSOCIATED
WITH SHORTWAVE PUSHES ACROSS THE AREA WED AFTERNOON. SOUNDINGS DO
SHOW A MARGINAL INCREASE IN MID LEVEL MOISTURE IN THE SOUTHWEST FLOW
AHEAD OF THE WAVE WHICH WILL INCREASE MID LEVEL CLOUD COVER. THE
LAYER UNDER 7K FT HOWEVER LOOKS TOO DRY FOR ANY PRECIP. COMBINATION
OF SUN...ESPECIALLY EARLY IN THE DAY...AND MODIFYING AIR MASS WILL
RESULT IN HIGHS A FEW DEGREES ABOVE CLIMO...LOW 60S. COLD ADVECTION
BEHIND THE FRONT WILL DROP TEMPS WED NIGHT...BUT COLD ADVECTION IS
NOT PARTICULARLY STRONG. LOWS WILL END UP CLOSE TO CLIMO.

CANADIAN HIGH BUILDS IN FROM THU AND THU NIGHT WITH TEMPS DROPPING
BACK TO CLIMO. DROPPED HIGHS A COUPLE DEGREES THU BUT MAY NOT BE
ENOUGH. WEAK COLD ADVECTION WILL CONTINUE INTO THE AFTERNOON HOURS
AND WILL HELP OFFSET SOME OF THE WARMING UNDER MOSTLY SUNNY SKIES.
WINDS CLOSE TO 20 KT NEAR THE TOP OF THE MIXED LAYER MAY END UP
MIXING DOWN IN THE FORM OF 15 TO 20 MPH GUSTS THU AFTERNOON. SURFACE
RIDGE AXIS SETTLES OVER THE AREA THU NIGHT WITH NORTHERLY FLOW
BECOMING CALM. ALTHOUGH THERE MAY BE SOME HIGH CLOUD COVER OVERNIGHT
LOW/MID LEVEL DRY AIR IN CONJUNCTION WITH CALM WINDS WILL RESULT IN
SOME RADIATIONAL COOLING. DROPPED LOWS A COUPLE DEGREES BUT MAY NEED
MORE REDUCTION. CURRENT FORECAST IS LOWS NEAR TO SLIGHTLY BELOW
CLIMO.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 300 PM TUESDAY...OTHER THAN A DRY...BUT ARCTIC...COLD FRONT
SATURDAY...QUIET WEATHER TO PERSIST THROUGH THE LONG TERM. BROAD
500MB TROUGHING ACROSS THE EAST WILL AMPLIFY SATURDAY AS A STRONG
S/W PUSHES A COLD FRONT THROUGH THE CAROLINAS. MOISTURE RETURN AHEAD
OF THIS FRONT IS QUITE LIMITED...SO FROPA IS EXPECTED TO BE DRY. LOW
LEVEL THICKNESSES AND 500MB HEIGHTS PLUMMET BEHIND THE
BOUNDARY...AND HAVE TRIED TO SHOW A NON-TYPICAL DIURNAL CURVE
SATURDAY WITH MAX TEMPS BEING REACHED LATE MORNING. TRUE WINTER-LIKE
AIR ARRIVES SUNDAY AND MONDAY WITH TEMPS AVERAGING AROUND 10 DEGREES
BELOW NORMAL...WITH LOWS IN THE 20S BOTH MORNINGS AND HIGHS SUNDAY
ONLY AROUND 50 DEGREES. TEMPS BEGIN TO MODERATE TO SEASONABLE NORMS
TUESDAY AND A STORM SYSTEM MAY BEGIN TO TAKE SHAPE ACROSS THE
SOUTHEAST...BUT THIS FAR OUT WILL KEEP FORECAST DRY THROUGH THE
EXTENDED.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 06Z...CLR SKIES EXPECTED EARLY THIS MORNING PERHAPS SOME
INCREASING THIN CIRRUS TOWARDS SUNRISE. GOOD RADIATIONAL
COOLING IS NOW OCCURRING WITH TEMPERATURE/DEWPOINT SPREADS
NARROWING. FORECAST NAM BUFR SOUNDING PROFILES CONTINUE TO SHOW
FAVORABLE PROFILES FOR FOG...BUT RUC PROFILES ARE MUCH DRIER IN THE
LOWEST 1000 FEET WHICH WOULD BE UNSUPPORTIVE OF IFR VSBYS. MOISTURE
IS LIMITED AND VERY SHALLOW BUT VERY DRY AIR IS NOTED ABOVE THE
INVERSION. NUMERICAL GUIDANCE INDICATES CALM SFC WINDS THROUGH
SUNRISE WITH VFR VISIBILITIES. CONFIDENCE IN SHALLOW GROUND FOG
DEVELOPMENT HAS INCREASED...THUS EXPECT MVFR VISIBILITIES TO DEVELOP
AT ALL TERMINALS THIS MORNING. THERE IS LOW CONFIDENCE THAT AT THE
LBT AND CRE TERMINALS IFR VISIBILITY COULD DEVELOP MAINLY AFTER
09Z...BUT FOR NOW THIS POTENTIAL IS NOT EXPLICIT IN THE FORECAST.

AFTER SUNRISE EXPECT INCREASING MID-LEVEL CLOUDS AT FLO/LBT AND BY
MID-MORNING AT THE COASTAL TERMINALS. LIGHT NORTHEAST WINDS WILL
BECOME WEST-NORTHWEST MID-LATE MORNING AT FLO/LBT AND AT THE COASTAL
TERMINALS IN THE AFTERNOON AS A SURFACE TROUGH MOVES THROUGH.

EXTENDED OUTLOOK...LOW CONFIDENCE FOR IFR/MORNING FOG FRIDAY. SLIGHT
CHANCE RAIN SATURDAY. OTHERWISE VFR.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 AM WEDNESDAY...VERY FEW CHANGES NEEDED TO THE PREVIOUS
FORECAST EARLY THIS MORNING. NORTH TO NORTHEAST SURFACE WINDS WILL
CONTINUE OVERNIGHT...5-10 KT NEAR THE COAST WITH 10-15 KT WINDS
FARTHER OFFSHORE. SEAS ARE GENERALLY 2-3 FEET.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 PM MONDAY...FLOW WILL REMAIN NORTHERLY THROUGH THE PERIOD.
NORTHEAST WINDS WED BACK TO NORTHWEST WED NIGHT FOLLOWING PASSAGE OF
COLD FRONT LATE IN THE DAY. ALONG WITH THE SHIFT TO OFFSHORE SPEEDS
WILL PICK UP AS COLD ADVECTION DEVELOPS. POST FRONT THERE WILL BE A
SLIGHT PINCH TO THE GRADIENT...BUT WITH LIMITED COLD ADVECTION
OFFSHORE FLOW SHOULD BE LIMITED TO A SOLID 15 KT. SEAS 2 TO 3 FT WED
WILL CONTINUE INTO WED NIGHT BUT MAY TOUCH 4 FT LATE WED NIGHT WELL
AWAY FROM SHORE GIVEN THE OFFSHORE COMPONENT. NORTHERLY FLOW WILL
START TO DECREASE THU AND CONTINUE THU NIGHT AS SURFACE RIDGE AXIS
SETTLES SOUTH. SEAS WILL DROP TO 2 FT OR SE BY THE END OF THE PERIOD.

LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 300 PM TUESDAY...DIFFUSE PRESSURE GRADIENT FRIDAY CONTRIBUTES
TO LIGHT AND VARIABLE WINDS AND SEAS OF ONLY 1-2 FT. WINDS GRADUALLY
BECOME SW IN A PRE-FRONTAL REGIME LATE FRIDAY...AND INCREASE TO
10-15 KTS EARLY SATURDAY AS GRADIENT TIGHTENS AHEAD OF A STRONG COLD
FRONT. WITH LACK OF ANY MEANINGFUL SWELL PRESENT IN THE
SPECTRUM...WAVE CONDITIONS WILL BE DOMINATED BY 5 SEC SW WIND
WAVES...WITH AMPLITUDES RISING TO 3-4 FT BY SAT MORNING. A SHORT
DECREASE IN SEAS OCCURS DURING THE AFTN AS WINDS VEER TO THE NORTH
WITH THE FROPA...BUT RISE QUICKLY AGAIN LATE SAT...AND ESPECIALLY
SUN AS STRONG COLD AIR ADVECTION COMMENCES. NORTH WINDS INCREASE TO
20 KTS AND SEAS BUILD TO 4-5 FT...WITH SCEC CRITERIA CONDITIONS
LIKELY DURING MUCH OF THE DAYLIGHT HOURS SUNDAY.

&&

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

&&

$$

NEAR TERM...TRA
SHORT TERM...LEBO
LONG TERM...WEISS
AVIATION...ROSS/TRA






AREA FORECAST DISCUSSION

NWS CHARLESTON WV

 109 AM EST WED FEB 8 2012

.SYNOPSIS...
LOW PRESSURE BRINGS RAIN AND SNOW LATE TONIGHT AND WEDNESDAY...WITH
LIGHT SNOW ACCUMULATION POSSIBLE NORTH. HIGH PRESSURE BUILDS IN
THURSDAY. ARCTIC COLD FRONT FRIDAY NIGHT FOR COLDER WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
UPDATED...
IN PROCESS OF PREPARING THE EARLY MORNING PACKAGE. CHANGES THUS
FAR TO POPS BASED ON UPSTREAM OBS...LATEST HRRR AND NAM SIMULATED
REFLECITIVITY COMBINED WITH LIFT/OMEGA FIELDS. STILL LOOKS LIKE
PCPN WILL INITIALLY FALL OUT OF MID DECK WHICH WILL GO TO
SATURATED THE COLUMN BLO. LOOKS LIKE SW VA AND SE OH MAY GET IN ON
ACTION FIRST...WITH SE OH BEING MORE INTO DEFORMATION AXIS TO
START. WILL BRING LKLY POPS ENTERING SE OH FROM W AT 12Z...AND
ALSO SW VA COUNTIES. SEE TWO MAIN AREAS OF PCPN...ONE WITH
DEFORMATION ACROSS SE OH AND ANOTHER STREAKING N UP THE MTN
CHAIN...WITH PCPN FILLING IN ACROSS THE LOWLANDS AS UPR LOW
APPROACHES. HAVENT GOT TO TEMPS YET WHICH IS THE CRITICAL PIECE
FOR DETERMINING PCPN TYPE. TEMPS AS OF 06Z HAVE ALREADY DIPPED
INTO LWR 30S OUTSIDE OF THE MTNS...WITH 20S SHOWING UP IN THE HIGH
TERRAIN. STILL LOOKING AT A QUICK HITTER...WITH SYS PULLING E BY
21Z OR SO.

PREVIOUS DISCUSSION BELOW...
LOW PRESSURE SYSTEM BRINGS RAIN AND SNOW LATE TONIGHT AND
WEDNESDAY. THIS SYSTEM IS STRONG ENOUGH TO INDUCE AN INVERTED
SURFACE TROUGH WEDNESDAY MORNING JUST WEST OF THE MOUNTAINS...THEN
THE COLD AIR COLLAPSES IN LATER IN THE DAY. THUS...WE HAVE A
TYPICAL WARM WEDGE JUST WEST OF THE MOUNTAINS WEDNESDAY MORNING
INTO EARLY WEDNESDAY AFTERNOON. WHILE THE TEMPS ALOFT...850 MB AND
ABOVE...ARE COLD ENOUGH FOR SNOW...EVEN IN THE WARM WEDGE...THE
BOUNDARY LAYER TO 925 MB WILL BE WARM ENOUGH FOR MAINLY A RAIN AND
SNOW MIX OVER MUCH OF THE AREA FOR THE BULK OF THE
PRECIPITATION...WHICH TAPERS OFF LATER IN THE DAY FROM WEST TO
EAST. THE MODELS DEPICT THIS NICELY...EVEN THOUGH THE GFS IS A BIT
WARMER WITH THE SURFACE TEMPS WEDNESDAY. WE EXPECT TEMPS TO BOTTOM
OUT BEFORE THE THICK CLOUDS MOVE IN LATER TONIGHT...SO A BIT OF A
RISE BEFORE DAWN. MODEL GUIDANCE IS CLOSE TONIGHT AND ACCEPTED. A
COMPROMISE LOOKS THE WAY TO GO WITH SURFACE TEMPS
WEDNESDAY...WHICH OUR FORECAST HAS TEMPS ABOVE FREEZING FOR MUCH
OF THE DAY...EXCEPT IN THE HIGHER ELEVATIONS OF THE NORTHERN
MOUNTAINS. NOT MUCH MOISTURE TO WORK WITH...BUT DYNAMICS WILL BE
STRONG ENOUGH TO SQUEEZE OUT A TENTH OR TWO OF LIQUID.
STILL...WITH MARGINAL TEMPS MOST AREAS...RELATIVELY WARM GROUND
AND PRECIP FALLING DURING THE DAY...SNOW ACCUMULATIONS WILL BE
LIMITED. WE LOOK FOR SNOW ACCUMULATIONS TO RANGE FROM POSSIBLY AN
INCH ACROSS THE NORTHWEST PART OF THE AREA TO A FEW INCHES IN THE
HIGHER ELEVATIONS OF THE NORTHERN MOUNTAINS. THUS...NO ADVISORY
CRITERIA MET.

&&

.SHORT TERM /TONIGHT THROUGH FRIDAY/...
WITH THE 850 MB THERMAL TROF HOLDING INTO THURSDAY MORNING...HAVE
LOW CONFIDENCE IN TIMING THE CLEARING OF THE LINGERING LOW LEVEL
CLOUD DECK.

TRIED TO SLOW THE CLEARING DOWN...AND LEAVE POPS HIGHER IN THE
MOUNTAINS LONGER...INTO WEDNESDAY NIGHT.  SNOW ACCUMULATIONS FOR
OVERNIGHT AN INCH OR LESS FIGURED...AND MOISTURE THINS.

THE 850 TO 925 MB WIND FLOW BECOMES WEAKER BY 12Z THURSDAY...SO
CONCERNED THE CLOUDS MAY HOLD LONGER ON THURSDAY...ESPECIALLY FROM
CRW ON SOUTH THROUGH THE SOUTHERN COAL FIELDS OF WEST VIRGINIA INTO
SOUTHWEST VIRGINIA ON THURSDAY.

HIGH PRESSURE IN VICINITY THURSDAY NIGHT INTO FRIDAY MORNING.

MOISTURE AND WINDS STILL INCREASE AHEAD OF THE ARCTIC FRONT FRIDAY
AFTERNOON.  HAVE CHANCE POPS INCREASES FROM NW TO SE 18Z FRIDAY TO
00Z SATURDAY.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ARCTIC FRONT SLICES THROUGH FRIDAY NIGHT AND SATURDAY WITH A ROUND
OF RAIN/SNOW SHOWERS QUICKLY TURNING TO ALL SNOW INTO THE EARLY
MORNING HOURS SATURDAY. STOUT COLD AIR ADVECTION BEHIND THE SYSTEM
WILL BRING A SPELL OF CHILLIER AIR...BELOW NORMAL VALUES FOR THIS
TIME OF YEAR. WEEKEND OVERNIGHT PERIODS WILL CARRY THE POTENTIAL FOR
EFFICIENT RADIATIONAL COOLING GIVEN THE CLEAR NIGHTS EXPECTED. WILL
NEED TO MONITOR SNOWFALL FROM THE FRONT...AS THIS COULD ENHANCE THE
COOLING. AS IT IS...HAVE GONE AGGRESSIVE IN THE OVERNIGHT LOWS
SATURDAY NIGHT FOR THE MOUNTAIN VALLEYS. COLD AIRMASS WILL NOT BE IN
A HURRY TO MODERATE OR LIFT OUT...AND WILL STAY BELOW NORMAL THROUGH
THE REMAINDER OF THE WEEKEND. WILL SEE A SLOW TICK UPWARDS IN THE
TEMPERATURES INTO EARLY NEXT WEEK.

LOW CONFIDENCE WITH A SURFACE TROUGH AFFECTING THE SOUTHERN
MOUNTAINS LATE MONDAY AND MONDAY NIGHT...AND DO NOT SEE MUCH IN THE
WAY OF CONSENSUS WITH THIS IN THE OPERATIONAL LONG TERM MODELS. WILL
CAP THE POPS AT LOW CHANCE...BUT EXPECT SOME CHANGE TO THIS PART OF
THE FORECAST OVER THE NEXT FEW MODEL RUNS.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
LOW END VFR STRATUS HANGING OVER SE OH WITH SOME MID/HI CLDS
INVADING FROM W AS OF 06Z. THIS WILL CONT TO BE CASE THRU
09Z...WITH STRATUS HOLDING FIRM ACROSS SE OH WITH REMAINDER OF
AREA SCT-BKN 8 TO 10 THSND FT CLDS.

CIGS WILL LWR INTO IFR TOWARD 12Z WITH PCPN ENTERING SW VA...FAR
WESTERN ZONES AND SE OH IN THE FORM OF -SN SE OH AND MORE OF A
RASN MIX NE KY AND SW VA. VSBY DEPENDANT ON FORM OF PCPN WITH SOME
2SM VSBY OR IN SN AND 3 TO 4 IN AREAS THAT MIX. THIS TREND EXPANDS
N AND E THRU 18Z...BEFORE PCPN CONFINES ITSELF TO MAINLY
CENTRAL/NORTHERN MTNS BY 21Z AS UPR LOW PULLS AWAY. LOW
CONFIDENCE..BUT FIGURE ON MIX CENTRAL AND SOUTHERN LOWLANDS WITH
SN ACROSS NORTH AND IN MTNS. GIVEN THE UNCERTAINITY IN PCPN TYPE
WENT WITH MORE OF A GENERAL 2SM VSBY AND 800 TO 1000FT CIGS IN
TAFS. COULD SEE SOME LOCAL LIFR VSBY IN ANY HEAVIER SNOWS...MOST
LKLY ACROSS THE MTNS AND PERHAPS SE OH.

AS SYS PULLS E THIS AFTN...LOW STRATUS WILL LINGER IN ITS
WAKE...WITH IFR CIGS FOR ALL TAF SITES THRU 06Z THU.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z THURSDAY...

FORECAST CONFIDENCE: LOW.

ALTERNATE SCENARIOS: CIGS AND VSBY COULD VARY BETWEEN MVFR AND
IFR OUTSIDE OF THE MTNS...DEPENDANT ON PCPN TYPE.

EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH:   TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW:    TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.

DATE                                   WED 02/08/12
UTC 1HRLY       06   07   08   09   10   11   12   13   14   15   16   17
EST 1HRLY       01   02   03   04   05   06   07   08   09   10   11   12
CRW CONSISTENCY  H    H    H    H    H    H    H    M    L    L    L    L
HTS CONSISTENCY  H    H    H    H    H    M    M    M    L    L    L    L
BKW CONSISTENCY  H    H    H    H    H    H    H    M    M    M    L    L
EKN CONSISTENCY  H    H    H    H    H    H    H    M    L    M    M    L
PKB CONSISTENCY  M    M    M    M    M    M    M    M    L    L    L    L
CKB CONSISTENCY  H    H    H    H    H    H    H    H    M    L    L    L

AFTER 06Z THURSDAY...
IFR CONDITIONS POSSIBLE IN THE MOUNTAINS AND LOWLAND COUNTIES
IMMEDIATELY ADJACENT WEDNESDAY NIGHT. IFR AGAIN POSSIBLE IN SNOW
SHOWERS FRIDAY NIGHT THROUGH SATURDAY NIGHT.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.

&&

$$
SYNOPSIS...KTB/26/JMV
NEAR TERM...JMV/30
SHORT TERM...KTB
LONG TERM...26
AVIATION...30









AREA FORECAST DISCUSSION...UPDATED

NWS SAN ANGELO TX

 1146 PM CST TUE FEB 7 2012

.DISCUSSION...
SEE AVIATION SECTION.

&&

.AVIATION...
PER TRENDS IN SATELLITE IMAGERY...A NEW LOW CLOUD FIELD /WITH MVFR
CEILINGS/ HAS PUSHED SOUTH ACROSS THE BIG COUNTRY. THE LATEST RUC
DATA INDICATES THAT THESE LOW CLOUDS WILL ADVANCE SOUTH TO NEAR
INTERSTATE 10 OVERNIGHT...AND PERSIST INTO THE MID-MORNING HOURS.
HAVE INITIALIZED THE KABI TAF WITH A BROKEN CEILING OF 2K FT. WILL
LEAN TOWARD THE RUC WITH THE DEVELOPMENT OF LOW CLOUDS AT THE TAF
SITES FARTHER SOUTH OVERNIGHT. SOME UNCERTAINTY IN HOW LONG THESE
LOW CLOUDS WILL PERSIST INTO WEDNESDAY MORNING...AND NONE OF THE
MODEL DATA HAS HANDLED THE LOW CLOUD FIELDS THAT WELL BEYOND
SEVERAL HOURS. CARRYING A SCATTERED VFR CLOUD GROUP AT ALL SITES
WEDNESDAY AFTERNOON AND EVENING. PER MODEL INDICATIONS...LOW CLOUDS
SHOULD BEGIN TO DEVELOP NORTH INTO OUR SOUTHERN COUNTIES BETWEEN 03Z
AND 06Z THURSDAY. NORTH WINDS OVERNIGHT AND WEDNESDAY MORNING WILL
VEER TO THE EAST WEDNESDAY AFTERNOON...AND TO THE SOUTHEAST WEDNESDAY
NIGHT.

19

&&

.PREV DISCUSSION... /ISSUED 1111 PM CST TUE FEB 7 2012/

UPDATE...

LATEST SATELLITE DATA INDICATE SKIES ARE CLEAR ACROSS MOST OF WEST
CENTRAL TEXAS...WHILE LOW CLOUDS ARE SPREADING INTO THE BIG
COUNTRY FROM THE NORTH. LATEST RUC AND NAM DATA INDICATE THE LOW
CLOUDS WILL CONTINUE TO PUSH SOUTH ACROSS WEST CENTRAL TEXAS FOR
THE REMAINDER OF TONIGHT. THUS...I HAVE INCREASED SKY GRIDS TO 100
PERCENT BY 12Z FOR ALL BUT OUR SOUTHERN COUNTIES. PLUS...WITH THE
INCREASING CLOUD COVER...I INCREASED OVERNIGHT LOWS A DEGREE OR
TWO FOR TONIGHT OVER SOME OF OUR NORTHERN COUNTIES. LATEST ZONE
PRODUCT REFLECTS THESE CHANGES.

HUBER

PREV DISCUSSION... /ISSUED 559 PM CST TUE FEB 7 2012/

DISCUSSION...
SEE AVIATION SECTION.

AVIATION...
VFR CONDITIONS...FOR THE MOST PART...WILL PREVAIL THROUGH THE NEXT 24
HOURS.THE POSSIBLE EXCEPTION IS AT KBBD AND KJCT BETWEEN 09Z AND
16Z WEDNESDAY. AREA OF CLOUDS WITH CEILINGS 4K-5K FT WILL OVERSPREAD
THE SOUTHERN PART OF WEST CENTRAL TEXAS THROUGH EARLY TONIGHT.
THIS TAF PACKAGE...BASED PARTLY ON GUIDANCE FROM THE 18Z NAM RH
AT 800MB...HAS CLOUD CEILINGS PERSISTING WELL INTO THE NIGHT AT
KSJT...KBBD AND KJCT. HOWEVER...WILL MONITOR SATELLITE TRENDS AND
MAY NEED TO AMEND WITH A LONGER PERIOD OF CLEARING AT THESE
SITES. OVERNIGHT...BOUNDARY LAYER MOISTURE FIELDS SUGGEST A LOW
CLOUD FIELD /WITH MVFR CEILINGS/ DEVELOPING ACROSS OUR EASTERN
COUNTIES. CARRYING A 2K-3K CEILING AT KBBD AND KJCT ROUGHLY
BETWEEN 09Z AND 16Z. ANTICIPATE THAT THE REST OF OUR AREA WILL
HAVE CLEAR TO PARTLY CLOUDY SKY CONDITION WEDNESDAY MORNING. IN
THE WAKE OF THE RECENT COLD FRONTAL PASSAGE... NORTH WINDS AT
10-15 KT WILL OCCUR THROUGH MUCH OF TONIGHT...WITH A FEW GUSTS TO
20 KT POSSIBLE THROUGH LATE EVENING. NORTH WINDS WILL VEER TO
NORTHEAST BY MIDDAY WEDNESDAY WITH A GRADUAL DECREASE IN SPEEDS.

19

PREV DISCUSSION... /ISSUED 325 PM CST TUE FEB 7 2012/

SHORT TERM...
COLD FRONT PROGRESSING SOUTHWARD ACROSS WEST CENTRAL TEXAS LATE THIS
AFTERNOON. LIFT WITH THE FRONT HAS HELPED EXPAND AN AREA OF LOW AND
MID CLOUDS ACROSS THE BIG COUNTRY. MODELS NOT DOING A GREAT JOB WITH
THESE CLOUDS...ALTHOUGH THE RUC HAS PICKED UP ON THEM TO SOME
DEGREE.  SUSPECT THESE CLOUDS WILL EXPAND SOUTH AND COVER MUCH OF
WEST CENTRAL TEXAS BY EVENING...BEFORE STARTING TO DECREASE.

DESPITE THE CLOUD COVER...STILL LOOKS TO BE A COLD NIGHT.
TEMPERATURES ACROSS THE PANHANDLE REMAIN IN THE LOW TO MID 30S THIS
AFTERNOON...SO AIR MASS IS CERTAINLY COLD. GUIDANCE NUMBERS ARE
PRETTY SIMILAR IN THE UPPER 20S AND LOWER 30S...AND NOT GOING TO
DEVIATE TOO MUCH. COLDEST READINGS WILL BE ACROSS THE NORTHERN AND
WESTERN BIG COUNTRY...WHERE AT LEAST SOME BREAKS IN THE CLOUDS WILL
DEVELOP.

COOL AGAIN ON WEDNESDAY...AS COLD ADVECTION CONTINUES. SURFACE HIGH
SLIDES OFF TO THE EAST INTO THE MISSISSIPPI VALLEY...SO WINDS WILL
BEGIN TO SWING AROUND TO THE EAST AND SOUTHEAST BY AFTERNOON.

07

LONG TERM...
AN UPPER LEVEL LOW WILL DEVELOP AT THE BASE OF THE UPPER LEVEL
TROUGH CURRENTLY OVER CALIFORNIA...THEN DIVE SOUTH TO SOUTHERN BAJA
CALIFORNIA BY THURSDAY MORNING. THIS WILL PUT WEST CENTRAL TEXAS IN
SOUTHWEST FLOW A LOT WITH INCREASING PACIFIC MOISTURE AND OCCASIONAL
DISTURBANCES TREKKING ACROSS THE REGION. AS THE PACIFIC MOISTURE
BEGINS TO INCREASE...CLOUD COVER WILL ALSO BE ON THE INCREASE.
EXPECT LOW TO MID LEVEL CLOUDS TO QUICKLY INCREASE BY EARLY THURSDAY
MORNING...WHICH SHOULD SERVE TO KEEP TEMPERATURES UP A
BIT...ESPECIALLY OVER THE SOUTHERN HALF OF THE AREA. LOW
TEMPERATURES ON THURSDAY MORNING WILL RANGE FROM THE LOWER 40S
SOUTH...TO NEAR 30 NORTH. A COOL/DREARY PATTERN WILL SETUP FOR
THURSDAY AND FRIDAY...WITH THE MAIN QUESTIONS BEING RAIN
CHANCES...AND QPF AMOUNTS. ECMWF AND GFS SOLUTIONS BEING TO DIVERGE
BEYOND THURSDAY AS THE GFS IS FASTER IN EJECTING THE LOW INTO NORTH
CENTRAL MEXICO...THEN TRACKING IT ACROSS TEXAS AS A WEAK OPEN WAVE.
THE ECMWF CONTINUES TO BE MUCH SLOWER...HANGING THE LOW OFF THE
PACIFIC COAST THROUGH SATURDAY. THE BEST DYNAMICS WITH THIS LOW WILL
REMAIN WELL SOUTH OF WEST CENTRAL TEXAS...AND HAVE TRIMMED POPS BACK
SLIGHTLY...THURSDAY AND FRIDAY. WOULD NOT BE SURPRISED TO SEE A FEW
SHOWERS AS OCCASIONAL DISTURBANCES EMBEDDED IN THE SOUTHWEST FLOW
ALOFT MOVE OVER THE AREA. DO NOT EXPECT MUCH QPF...AS ANY SHOWERS
THAT DO DEVELOP LOOK TO BE LIGHT AS THIS TIME. IN
ADDITION...DIFFERENCES ARISE IN THE HANDLING OF THE NEXT UPPER LEVEL
TROUGH MOVING ACROSS THE PLAINS ON FRIDAY. THE ECMWF IS DEEPER THAN
THE GFS WITH THE TROUGH...HENCE MORE AGGRESSIVE WITH THE
FRONT...PUSHING IT THROUGH THE AREA ON FRIDAY. AS THE FRONT MOVES
THROUGH...THE ECMWF DEVELOPS SHOWERS ALONG THE BOUNDARY ON FRIDAY.
FOR NOW...HAVE LEFT FRIDAY DRY...BUT FUTURE SHIFTS WILL NEED TO
MONITOR. THE NEXT ISSUE IS THE NEXT UPPER LEVEL TROUGH THAT IS
FORECAST TO SWING ACROSS THE PLAINS SUNDAY INTO MONDAY. MODELS HAVE
BEEN FAIRLY CONSISTENT IN SHOWING INCREASING RAIN CHANCES AHEAD OF
THIS TROUGH...AND HAVE ADDED IN SLIGHT CHANCE POPS SUNDAY AND SUNDAY
NIGHT.

DANIELS

&&

.PRELIMINARY POINT TEMPS/POPS...
ABILENE  28  47  32  56  37 /   0  10  10  10  20
SAN ANGELO  33  52  36  54  38 /   0  10  10  10  20
JUNCTION  36  56  39  56  39 /  10  10  10  20  20

&&

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

$$















AREA FORECAST DISCUSSION

NWS SAN ANGELO TX

 1111 PM CST TUE FEB 7 2012

.UPDATE...

LATEST SATELLITE DATA INDICATE SKIES ARE CLEAR ACROSS MOST OF WEST
CENTRAL TEXAS...WHILE LOW CLOUDS ARE SPREADING INTO THE BIG
COUNTRY FROM THE NORTH. LATEST RUC AND NAM DATA INDICATE THE LOW
CLOUDS WILL CONTINUE TO PUSH SOUTH ACROSS WEST CENTRAL TEXAS FOR
THE REMAINDER OF TONIGHT. THUS...I HAVE INCREASED SKY GRIDS TO 100
PERCENT BY 12Z FOR ALL BUT OUR SOUTHERN COUNTIES. PLUS...WITH THE
INCREASING CLOUD COVER...I INCREASED OVERNIGHT LOWS A DEGREE OR
TWO FOR TONIGHT OVER SOME OF OUR NORTHERN COUNTIES. LATEST ZONE
PRODUCT REFLECTS THESE CHANGES.

HUBER

&&

.PREV DISCUSSION... /ISSUED 559 PM CST TUE FEB 7 2012/

DISCUSSION...
SEE AVIATION SECTION.

AVIATION...
VFR CONDITIONS...FOR THE MOST PART...WILL PREVAIL THROUGH THE NEXT 24
HOURS.THE POSSIBLE EXCEPTION IS AT KBBD AND KJCT BETWEEN 09Z AND
16Z WEDNESDAY. AREA OF CLOUDS WITH CEILINGS 4K-5K FT WILL OVERSPREAD
THE SOUTHERN PART OF WEST CENTRAL TEXAS THROUGH EARLY TONIGHT.
THIS TAF PACKAGE...BASED PARTLY ON GUIDANCE FROM THE 18Z NAM RH
AT 800MB...HAS CLOUD CEILINGS PERSISTING WELL INTO THE NIGHT AT
KSJT...KBBD AND KJCT. HOWEVER...WILL MONITOR SATELLITE TRENDS AND
MAY NEED TO AMEND WITH A LONGER PERIOD OF CLEARING AT THESE
SITES. OVERNIGHT...BOUNDARY LAYER MOISTURE FIELDS SUGGEST A LOW
CLOUD FIELD /WITH MVFR CEILINGS/ DEVELOPING ACROSS OUR EASTERN
COUNTIES. CARRYING A 2K-3K CEILING AT KBBD AND KJCT ROUGHLY
BETWEEN 09Z AND 16Z. ANTICIPATE THAT THE REST OF OUR AREA WILL
HAVE CLEAR TO PARTLY CLOUDY SKY CONDITION WEDNESDAY MORNING. IN
THE WAKE OF THE RECENT COLD FRONTAL PASSAGE... NORTH WINDS AT
10-15 KT WILL OCCUR THROUGH MUCH OF TONIGHT...WITH A FEW GUSTS TO
20 KT POSSIBLE THROUGH LATE EVENING. NORTH WINDS WILL VEER TO
NORTHEAST BY MIDDAY WEDNESDAY WITH A GRADUAL DECREASE IN SPEEDS.

19

PREV DISCUSSION... /ISSUED 325 PM CST TUE FEB 7 2012/

SHORT TERM...
COLD FRONT PROGRESSING SOUTHWARD ACROSS WEST CENTRAL TEXAS LATE THIS
AFTERNOON. LIFT WITH THE FRONT HAS HELPED EXPAND AN AREA OF LOW AND
MID CLOUDS ACROSS THE BIG COUNTRY. MODELS NOT DOING A GREAT JOB WITH
THESE CLOUDS...ALTHOUGH THE RUC HAS PICKED UP ON THEM TO SOME
DEGREE.  SUSPECT THESE CLOUDS WILL EXPAND SOUTH AND COVER MUCH OF
WEST CENTRAL TEXAS BY EVENING...BEFORE STARTING TO DECREASE.

DESPITE THE CLOUD COVER...STILL LOOKS TO BE A COLD NIGHT.
TEMPERATURES ACROSS THE PANHANDLE REMAIN IN THE LOW TO MID 30S THIS
AFTERNOON...SO AIR MASS IS CERTAINLY COLD. GUIDANCE NUMBERS ARE
PRETTY SIMILAR IN THE UPPER 20S AND LOWER 30S...AND NOT GOING TO
DEVIATE TOO MUCH. COLDEST READINGS WILL BE ACROSS THE NORTHERN AND
WESTERN BIG COUNTRY...WHERE AT LEAST SOME BREAKS IN THE CLOUDS WILL
DEVELOP.

COOL AGAIN ON WEDNESDAY...AS COLD ADVECTION CONTINUES. SURFACE HIGH
SLIDES OFF TO THE EAST INTO THE MISSISSIPPI VALLEY...SO WINDS WILL
BEGIN TO SWING AROUND TO THE EAST AND SOUTHEAST BY AFTERNOON.

07

LONG TERM...
AN UPPER LEVEL LOW WILL DEVELOP AT THE BASE OF THE UPPER LEVEL
TROUGH CURRENTLY OVER CALIFORNIA...THEN DIVE SOUTH TO SOUTHERN BAJA
CALIFORNIA BY THURSDAY MORNING. THIS WILL PUT WEST CENTRAL TEXAS IN
SOUTHWEST FLOW A LOT WITH INCREASING PACIFIC MOISTURE AND OCCASIONAL
DISTURBANCES TREKKING ACROSS THE REGION. AS THE PACIFIC MOISTURE
BEGINS TO INCREASE...CLOUD COVER WILL ALSO BE ON THE INCREASE.
EXPECT LOW TO MID LEVEL CLOUDS TO QUICKLY INCREASE BY EARLY THURSDAY
MORNING...WHICH SHOULD SERVE TO KEEP TEMPERATURES UP A
BIT...ESPECIALLY OVER THE SOUTHERN HALF OF THE AREA. LOW
TEMPERATURES ON THURSDAY MORNING WILL RANGE FROM THE LOWER 40S
SOUTH...TO NEAR 30 NORTH. A COOL/DREARY PATTERN WILL SETUP FOR
THURSDAY AND FRIDAY...WITH THE MAIN QUESTIONS BEING RAIN
CHANCES...AND QPF AMOUNTS. ECMWF AND GFS SOLUTIONS BEING TO DIVERGE
BEYOND THURSDAY AS THE GFS IS FASTER IN EJECTING THE LOW INTO NORTH
CENTRAL MEXICO...THEN TRACKING IT ACROSS TEXAS AS A WEAK OPEN WAVE.
THE ECMWF CONTINUES TO BE MUCH SLOWER...HANGING THE LOW OFF THE
PACIFIC COAST THROUGH SATURDAY. THE BEST DYNAMICS WITH THIS LOW WILL
REMAIN WELL SOUTH OF WEST CENTRAL TEXAS...AND HAVE TRIMMED POPS BACK
SLIGHTLY...THURSDAY AND FRIDAY. WOULD NOT BE SURPRISED TO SEE A FEW
SHOWERS AS OCCASIONAL DISTURBANCES EMBEDDED IN THE SOUTHWEST FLOW
ALOFT MOVE OVER THE AREA. DO NOT EXPECT MUCH QPF...AS ANY SHOWERS
THAT DO DEVELOP LOOK TO BE LIGHT AS THIS TIME. IN
ADDITION...DIFFERENCES ARISE IN THE HANDLING OF THE NEXT UPPER LEVEL
TROUGH MOVING ACROSS THE PLAINS ON FRIDAY. THE ECMWF IS DEEPER THAN
THE GFS WITH THE TROUGH...HENCE MORE AGGRESSIVE WITH THE
FRONT...PUSHING IT THROUGH THE AREA ON FRIDAY. AS THE FRONT MOVES
THROUGH...THE ECMWF DEVELOPS SHOWERS ALONG THE BOUNDARY ON FRIDAY.
FOR NOW...HAVE LEFT FRIDAY DRY...BUT FUTURE SHIFTS WILL NEED TO
MONITOR. THE NEXT ISSUE IS THE NEXT UPPER LEVEL TROUGH THAT IS
FORECAST TO SWING ACROSS THE PLAINS SUNDAY INTO MONDAY. MODELS HAVE
BEEN FAIRLY CONSISTENT IN SHOWING INCREASING RAIN CHANCES AHEAD OF
THIS TROUGH...AND HAVE ADDED IN SLIGHT CHANCE POPS SUNDAY AND SUNDAY
NIGHT.

DANIELS

&&

.PRELIMINARY POINT TEMPS/POPS...
ABILENE  28  47  32  56  37 /   0  10  10  10  20
SAN ANGELO  33  52  36  54  38 /   0  10  10  10  20
JUNCTION  36  56  39  56  39 /  10  10  10  20  20

&&

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

$$

HUBER







AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 956 AM CST WED FEB 8 2012

.DISCUSSION...
356 AM CST

NEAR TERM CONCERNS THIS MORNING INCLUDE LIGHT SNOW ACROSS SOUTHERN
PARTS OF THE CWA...LINGERING LIGHT LAKE EFFECT SNOW THIS MORNING
OVER NORTHERN LAKE AND PORTER COUNTIES...AND CLOUD TRENDS ACROSS THE
AREA TODAY. LOOMING ON THE HORIZON IS A PUNCH OF ARCTIC AIR WHICH
ARRIVES FRIDAY...WITH THE FOCUS ON COLDER TEMPS AND THE POTENTIAL
FOR MORE SIGNIFICANT LAKE EFFECT SNOW ACROSS NORTHEAST IL AND
NORTHWEST INDIANA INTO SATURDAY.

LIGHT SNOW WAS OCCURRING EARLY THIS MORNING GENERALLY SOUTH OF A VYS
TO VPZ LINE...IN ASSOCIATION WITH AN UPPER DISTURBANCE MOVING ACROSS
DOWNSTATE IL INTO THE LOWER OHIO VALLEY. STRONGEST FORCING WITH THIS
SYSTEM WAS OCCURRING SOUTH OF THE CWA...WITH SFC OBS ACROSS OUR
SOUTHERN COUNTIES INDICATING  VISIBILITIES GENERALLY IN THE 3-7SM
RANGE AND SUGGESTING ONLY MINOR ACCUMULATIONS. LIGHT SNOW WILL
CONTINUE ACROSS THE SOUTH THIS MORNING...SHIFTING MAINLY EAST OF
INTERSTATE 57 BY 12Z. LITTLE ADDITIONAL ACCUMULATION IS EXPECTED.

FARTHER NORTH...A WEAK BAND OF LAKE EFFECT SNOW WAS IMPINGING ON
NORTHWEST LAKE COUNTY AND FAR SOUTHEAST COOK COUNTY. BAND WAS
HEAVIER FOR A TIME LATE LAST EVENING...WITH SOME ACCUMULATION NOTED
ON WEB CAMS ALONG THE INTERSTATES. RADAR RETURNS HAVE WEAKENED
CONSIDERABLY...AND HIGH RES MODEL GUIDANCE SEEMS TO HAVE CAPTURED
THIS TREND NICELY. BOTH RUC AND NAM DO INDICATE THAT SLIGHT COOLING
AROUND 900 HPA MAY SLIGHTLY IMPROVE THE LOW-LEVEL THERMODYNAMIC
PROFILE AROUND 12Z THIS MORNING...BEFORE EQUILIBRIUM HEIGHTS LOWER
BELOW 4000 FT AND LOW LEVEL WINDS BACK AROUND TO THE NORTHWEST BY
MIDDAY. THEREFORE EXPECT LIGHT SNOW SHOWERS TO CONTINUE THROUGH MID
MORNING...SHIFTING EAST AND WEAKENING WITH TIME IN THE 15-18Z
PERIOD. CURRENT WEB CAM VIEWS FROM 80/94 NEAR HAMMOND INDICATE
CURRENT ACTIVITY HAVING LITTLE/NO IMPACT ON VISIBILITY AT 330
AM...AND HAVE ONLY INCLUDED AN ADDITIONAL TENTH OF AN INCH OF
SNOWFALL THIS MORNING MAINLY ACROSS NORTHERN LAKE COUNTY...THOUGH
WILL MONITOR FOR ANY SIGNS OF BETTER DEVELOPMENT PRIOR TO SUNRISE.

GOES 11-3.9 MICRON IMAGERY SHOWS CLEARING OF LOW CLOUDS WAS
OCCURRING ACROSS FAR NORTHWEST IL EARLY THIS MORNING...THOUGH LOW
CLOUDS STRETCHED BACK ACROSS A LARGE PORTION OF CENTRAL IA. A SHORT
WAVE TROUGH DIGGING SOUTHEAST ACROSS THE HAWKEYE STATE MAY SLOW
CLEARING FOR A TIME THIS MORNING...BEFORE THE MID-LEVEL VORT AND
TROUGH AXIS PASS INTO CENTRAL IL EARLY THIS AFTERNOON. DRIER LOW
LEVEL AIR JUST UPSTREAM WILL ADVECT INTO THE AREA FROM THE NORTHWEST
HOWEVER WHICH SHOULD ALLOW CLEARING FROM THE NORTH/NORTHWEST THROUGH
THE DAY...WITH SOUTHEASTERN COUNTIES CLEARING LAST. MODEL
TIME/HEIGHT SECTIONS THEN APPEAR QUITE DRY TONIGHT THROUGH THURSDAY.
TEMPERATURE GUIDANCE IN FAIRLY CLOSE AGREEMENT DURING THIS PERIOD
AND GENERALLY USED A BLEND LEANING A LITTLE TOWARD THE COOLER
NUMBERS TODAY...AND TOWARD THE WARMER END OF THE RANGE WITH MORE SUN
AND WEAK WARM ADVECTION DEVELOPING THURSDAY.

GUIDANCE CONTINUES TO DEPICT SIGNIFICANT AMPLIFICATION OF THE UPPER
FLOW FOR THE END OF THE WEEK...WITH LARGE TROUGH DEVELOPING OVER
MUCH OF EASTERN NORTH AMERICA AND AT LEAST A TEMPORARY PUSH OF
ARCTIC AIR. MAIN AREA OF LOW PRESSURE IS PROGGED TO DEVELOP JUST
NORTH OF LAKE SUPERIOR ON THURSDAY AHEAD OF MID-LEVEL SHORT WAVE...
WITH UPPER WAVE AND SURFACE COLD FRONT PUSHING ACROSS THE FORECAST
AREA EARLY FRIDAY. MODELS INDICATE CONSIDERABLE DRY AIR IN THE
850-650 HPA LAYER PRECLUDING MUCH OF A PRECIPITATION THREAT...THOUGH
FAIRLY STRONG ISENTROPIC ASCENT IN THE WARM ADVECTION AHEAD OF THE
TROUGH MAY RESULT IN ENOUGH SATURATION IN THE 280-285 K LAYER TO
PRODUCE SOME FLURRIES FRIDAY MORNING. STRONG COLD ADVECTION ON
BLUSTERY NORTHERLY WINDS FRIDAY WILL LIKELY PRODUCE FALLING DAYTIME
TEMPS INTO THE 20S...WITH 850 HPA TEMPS FROM GFS/ECMWF DEPICTING -17
TO -19 C OVER THE AREA BY 12Z SATURDAY.

BESIDES THE COLD...THE REAL FORECAST CONCERN IN THE FRIDAY-SATURDAY
PERIOD IS THE POTENTIAL FOR LAKE EFFECT SNOW INTO NORTHEAST IL AND
NORTHWEST INDIANA. LAKE SURFACE TO 850 HPA DELTAS INCREASE INTO THE
LOW 20S LATE FRIDAY THROUGH SATURDAY MORNING...DURING A PERIOD IN
WHICH THE LOW LEVEL WINDS WILL BE NORTH-NORTHEAST DOWN THE FULL
FETCH OF THE LAKE. FORECAST SOUNDINGS INDICATE EQUILIBRIUM LEVELS
RISING TO NEAR 9000 FT BY 12Z SATURDAY...WITH LAKE INDUCED CAPES OF
400-500 J/KG. THIS WOULD SUGGEST THE POTENTIAL FOR SOME SIGNIFICANT
ACCUMULATING LAKE EFFECT FROM FRIDAY AFTERNOON THROUGH SATURDAY
MORNING. ONLY LIMITING FACTOR WOULD BE THE VERY DRY ARCTIC AIR
SPREADING ACROSS THE WESTERN LAKES...THOUGH THE LONG FETCH WILL
LIKELY PROVIDE ENOUGH MOISTURE FLUX TO MAKE UP FOR THE DRYNESS OF
THE AIRMASS. WILL BE INTERESTING TO SEE SOME OF THE HIGH RESOLUTION
GUIDANCE AS THE FRIDAY-SATURDAY PERIOD APPROACHES. FOR NOW HAVE
INCREASED POPS FOR THE LAKESIDE COUNTIES...AND WILL HIGHLIGHT
POTENTIAL FOR ACCUMULATING LAKE SNOWS IN THE HAZARDOUS WEATHER
OUTLOOK.

LONGER RANGE GUIDANCE IN A LITTLE BETTER AGREEMENT IN SHIFTING UPPER
TROUGH OFF TO THE EAST SUNDAY...AND BUILDING SURFACE HIGH PRESSURE
RIDGE IN FROM THE WEST SUNDAY NIGHT. WARM ADVECTION WORKS TO PUSH
THE ARCTIC AIR AWAY MONDAY AS LOW LEVEL WINDS SHIFT TO THE SOUTH.
BOTH OPERATIONAL ECMWF AND GFS INDICATE A SHORT WAVE LIFTING
NORTHEAST ACROSS THE REGION LATE MONDAY SUGGESTING POTENTIAL FOR
SOME LIGHT SNOW MONDAY NIGHT INTO TUESDAY...WITH TEMPS CLIMBING A
BIT BACK ABOVE NORMAL.

RATZER

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 16Z...

* NONE.

KJB

//DISCUSSION...UPDATED 12Z...

HIGH PRESSURE BUILDING ACROSS THE AREA WILL PROVIDE RELATIVELY QUIET
WEATHER AND WILL EVENTUALLY CLEAR OUT CLOUD COVER. THIS MORNING...
LOW LEVEL MOISTURE HAS VERY SLOWLY BEEN ERODING FROM THE NORTHWEST
NEARLY STALLING AT RFD. RUC GUIDANCE SUGGESTS THAT LOW CLOUDS MAY
LINGER INTO THE LATE MORNING OR EARLY AFTERNOON ACROSS THE CHICAGO
AREA...THUS OPTED TO SLOW CLEARING ACROSS ORD/MDW FOR SEVERAL
HOURS. STILL...THE CLOUD DECK HAS BEEN GRADUALLY IMPROVING THROUGH
THE NIGHT AND DO NOT EXPECT MVFR CONDITIONS TO RETURN. NORTHERLY
WINDS THIS MORNING WILL BACK TO THE WEST THROUGH THE DAY AS HIGH
PRESSURE SLIDES SOUTH OF THE FORECAST AREA. FEW LINGERING LAKE
EFFECT SNOW SHOWERS THIS MORNING ACROSS NORTHWEST INDIANA WILL
CONTINUE TO WEAKEN AND SHIFT FARTHER EAST AWAY FROM THE CHICAGO/NW
INDIANA TERMINALS AS WINDS BACK. BMD

//ORD AND MDW CONFIDENCE...UPDATED 16Z...

* HIGH CONFIDENCE ON ALL FORECAST ELEMENTS.

KJB

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

THURSDAY NIGHT...VFR.
FRIDAY/SATURDAY...CHC LAKE EFFECT SNOW WITH MVFR/IFR POSSIBLE.
SUNDAY/MONDAY...VFR.
TUESDAY...SLT CHC RAIN/SNOW.
BMD

&&

.MARINE...
315 AM CST

FOLLOWING THE PASSAGE OF A COLD FRONT AND WITH HIGH PRESSURE
BUILDING ACROSS THE NORTHERN PLAINS AND UPPER MISSISIPPI
VALLEY...WINDS WILL GRADUALLY DIMINISH. AS THE HIGH PRESSURE SAGS
TO THE SOUTHEAST WEDNESDAY AND THURSDAY...WINDS WILL BECOME
WESTERLY TO 25KT AND EVENTUALLY SOUTHWESTERLY...AS ANOTHER ARCTIC
COLD FRONT APPROACHES. THIS FRONT WILL PUSH ACROSS THE LAKE
THURSDAY NIGHT. A STRONG PUSH OF COLD AIR MAY BRING WINDS UP TO
GALE FORCE OVER THE FAR NORTHERN PORTIONS OF THE LAKE LATE
THURSDAY INTO THURSDAY NIGHT.

KREIN

&&

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

$$






AREA FORECAST DISCUSSION

NWS LINCOLN IL

 914 AM CST WED FEB 8 2012

.DISCUSSION...
ISSUED 915 AM CST WED FEB 8 2012

WILL BE UPDATING THE FORECAST SHORTLY TO ADJUST THE MORNING PERIOD
WITH LIGHT SNOW AND FLURRIES OVER EASTERN IL WITH LITTLE OR NO
ADDITIONAL ACCUMULATIONS EXPECTED. ALSO ADJUSTING THE SKY COVER
TODAY WITH SLOWING CLEARING DOWN A BIT FROM THE NORTH. HIGHS 32 TO
38F LOOK ON TRACK WITH MILDEST READINGS IN SE IL.

FAIRLY STRONG UPPER LEVEL TROF OVER THE MIDWEST INCLUDING IL HAD A
LARGE AREA OF LOW CLOUDS OVER MUCH OF MO/IL/IN AND SE IA. THERE
WAS A CLEAR SLOT OVER NW IL AS FAR SOUTH AS PEORIA. AREA OF VERY
LIGHT SNOW AND FLURRIES WAS FROM BLOOMINGTON/NORMAL NE AND
DRIFTING SE TOWARD CHAMPAIGN/URBANA. TEMPS RANGED FROM THE UPPER
20S OVER CENTRAL IL NW OF I-70...TO THE MID 30S IN SE IL FROM
ROBINSON TO FLORA SE. NW WINDS 7 TO 13 MPH WAS USHERING IN DRIER
AIR WITH DEWPOINTS RANGING FROM THE UPPER TEENS AND LOWER 20S NW
OF I-55 TO THE UPPER 20S TO NEAR 30F FROM DANVILLE TO TAYLORVILLE
SE.

HI-RESOLUTION 12Z HRRR MODEL ACTUALLY SHOWS POCKETS OF VERY LIGHT
SNOW SHOWERS AND FLURRIES LINGERING OVER CENTRAL IL THROUGH THE
DAY. 12Z NAM...SREF AND RUC MODELS SHOW BRUN OF THE LIGHT SNOW
EAST OF IL TODAY WITH LIGHT POCKETS OF QPF OVER EAST CENTRAL IL
THIS MORNING WHICH BETTER SUPPORTS RADAR TENDS AND LEANED IN THIS
DIRECTION. DID SLOW CLEARING OF THE LOW CLOUDS FROM THE NORTH TODAY
WITH LOW CLOUDS LINGERING MUCH OF TODAY OVER SE IL. 1035 MB HIGH
PRESSURE OVER EASTERN NEBRASKA WILL SETTLE INTO THE MID MS VALLEY
BY THU MORNING HELPING CLEAR THE REST OF THE LOW CLOUDS TONIGHT
AND BRINGING SEASONABLY COLD TEMPS TODAY AND TONIGHT. NW WINDS 7
TO 13 MPH TODAY TO BECOME LIGHT WEST DURING TONIGHT AS HIGH
PRESSURE SETTLES IN.

HUETTL

&&

.AVIATION...
ISSUED 530 AM CST WED FEB 8 2012

THE WEATHER SYSTEM THAT PRODUCED THE LIGHT PRECIPITATION ACRS THE
AREA LAST NIGHT INTO EARLY THIS MORNING WAS BEGINNING TO SHIFT
OFF TO OUR EAST. ALREADY SEEING SKIES CLEAR UP TO OUR NORTH BUT
SOME PATCHES OF MVFR CIGS WERE NOTED ON THE SFC OBS ACRS PARTS
OF EAST CENTRAL AND NE IOWA. TIMING OF CLEARING ACRS THE FCST
AREA THE MAIN FORECAST CHALLENGE THIS MRNG...WITH VFR CONDITIONS
EXPECTED TO OVERSPREAD THE ENTIRE AREA LATER THIS AFTN OR EARLY
THIS EVENING AS HIGH PRESSURE SETTLES IN FROM THE NORTHWEST.

STILL SEEING VARIABLE CEILING HEIGHTS TO OUR NW DESPITE THE PRECIP
SLOWLY MOVING OUT OF THE AREA. PREVAILING CIGS WERE FROM 3500-4500
FEET BUT OCCASIONALLY LOWER TO 1200 FEET...OR EVEN DROP TO BELOW
1000 FEET WITH VSBYS ARND 3 MILES IN LIGHT SNOW AND FOG. FEEL THE
PRECIP WILL LINGER IN CMI AND DEC THRU MID MORNING WITH NOT MUCH
MORE FALLING AT PIA AND SPI AFTR 13Z.

SFC WINDS WILL BE MAINLY FROM A NORTHWEST DIRECTION AT 10 TO 15
KNOTS TODAY...AND THEN TEND TO BACK MORE INTO A WESTERLY DIRECTION
LATE THIS AFTN AND EVENING WITH SPEEDS DECREASING TO AROUND 5 KTS.

SMITH
&&

.PREV DISCUSSION...
ISSUED 250 AM CST WED FEB 8 2012

THE SHORTWAVE MOVING ACROSS THE CENTRAL U.S. WAS CROSSING ILLINOIS
EARLY THIS MORNING...PER WATER VAPOR IMAGERY. AREA OF LIGHT
SNOW...WHICH HAD PRODUCED A DUSTING...HAD LARGELY TAPERED IN
AREAS NORTH OF I-72. DID HAVE SOME LIGHT FREEZING DRIZZLE MIXED IN
EARLY ON AROUND PEORIA AND GALESBURG.

PRIMARY FORECAST ISSUES FOR THIS PACKAGE INVOLVE THE COLD AIR FOR
THIS WEEKEND...AS WELL AS PRECIPITATION CHANCES BEGINNING ON MONDAY.

SHORT TERM...TODAY THROUGH SATURDAY...

HIGH RESOLUTION MODELS STILL SHOWING LIGHT SNOW LINGERING OVER
THE EASTERN CWA EARLY THIS MORNING. REGIONAL RADAR LOOPS SHOWING
SOME PRECIPITATION STILL PRESENT AS FAR NORTH AS THE I-80
CORRIDOR IN NORTHEAST ILLINOIS...MOVING SOUTHWARD...SO THIS
SCENARIO SEEMS PLAUSIBLE. WILL KEEP 30-50 PERCENT POPS GOING EAST
OF I-57 EARLY THIS MORNING BEFORE TAPERING TO FLURRIES.
OTHERWISE...A QUIET PERIOD IS EXPECTED FROM LATE THIS AFTERNOON
THROUGH THURSDAY...AS HIGH PRESSURE DRIFTS SOUTHEAST INTO THE
TENNESSEE VALLEY.

THE COLD SNAP WHICH HAS BEEN ADVERTISED FOR THE LAST SEVERAL DAYS
IS STILL ON TRACK. 00Z MODELS IN GOOD AGREEMENT IN SWEEPING A COLD
FRONT ACROSS THE FORECAST AREA ON FRIDAY. THE FAR SOUTHEAST MAY
STAY IN THE WARMER AIR LONG ENOUGH TO REACH WELL INTO THE 40S...
BUT TEMPERATURES ELSEWHERE IN THE AFTERNOON WILL BE STEADY OR
FALLING. HAVE LOWERED TEMPERATURES FRIDAY NIGHT AND SATURDAY BY A
FEW MORE DEGREES FROM THE EARLIER VALUES. SOME OF THE GUIDANCE
SUGGESTS EVEN COLDER READINGS...BUT LACK OF SNOW COVER MAY HINDER
THAT THOUGHT. THE FRONT ITSELF IS LARGELY EXPECTED TO COME THROUGH
DRY IN OUR AREA...AND WILL ONLY GO WITH 20 POPS ACROSS THE EAST ON
FRIDAY MORNING.

LONG TERM...SUNDAY THROUGH TUESDAY...

TEMPERATURES ON SUNDAY EXPECTED TO STILL BE BELOW FREEZING IN MOST
AREAS...AS CENTER OF SURFACE HIGH MOVES OVER THE MISSISSIPPI
VALLEY. NEXT POINT OF CONCERN IS WITH A SHORTWAVE THAT WILL BE
MOVING OUT OF THE ROCKIES SUNDAY NIGHT. NARROW UPPER RIDGING WILL
OCCUR ACROSS THE PLAINS ON SUNDAY. THE ECMWF IS A BIT SLOWER THAN
THE GFS/CANADIAN MODELS IN BREAKING THIS RIDGE DOWN...MAINLY DUE
TO A DEEP TROUGH/CUTOFF LOW EXTENDING SOUTH FROM NOVA SCOTIA OVER
THE WESTERN ATLANTIC ON MONDAY. HAVE NOT MADE MUCH CHANGE IN THE
PRECIPITATION CHANCES FOR NOW...MAINLY IN THE SLIGHT CHANCE
RANGE...BUT MOST LIKELY PRECIPITATION OCCURRENCE LOOKS TO BE
MONDAY NIGHT IF IT DID OCCUR.

GEELHART

&&

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

$$








AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 801 AM CST WED FEB 8 2012

.DISCUSSION...
356 AM CST

NEAR TERM CONCERNS THIS MORNING INCLUDE LIGHT SNOW ACROSS SOUTHERN
PARTS OF THE CWA...LINGERING LIGHT LAKE EFFECT SNOW THIS MORNING
OVER NORTHERN LAKE AND PORTER COUNTIES...AND CLOUD TRENDS ACROSS THE
AREA TODAY. LOOMING ON THE HORIZON IS A PUNCH OF ARCTIC AIR WHICH
ARRIVES FRIDAY...WITH THE FOCUS ON COLDER TEMPS AND THE POTENTIAL
FOR MORE SIGNIFICANT LAKE EFFECT SNOW ACROSS NORTHEAST IL AND
NORTHWEST INDIANA INTO SATURDAY.

LIGHT SNOW WAS OCCURRING EARLY THIS MORNING GENERALLY SOUTH OF A VYS
TO VPZ LINE...IN ASSOCIATION WITH AN UPPER DISTURBANCE MOVING ACROSS
DOWNSTATE IL INTO THE LOWER OHIO VALLEY. STRONGEST FORCING WITH THIS
SYSTEM WAS OCCURRING SOUTH OF THE CWA...WITH SFC OBS ACROSS OUR
SOUTHERN COUNTIES INDICATING  VISIBILITIES GENERALLY IN THE 3-7SM
RANGE AND SUGGESTING ONLY MINOR ACCUMULATIONS. LIGHT SNOW WILL
CONTINUE ACROSS THE SOUTH THIS MORNING...SHIFTING MAINLY EAST OF
INTERSTATE 57 BY 12Z. LITTLE ADDITIONAL ACCUMULATION IS EXPECTED.

FARTHER NORTH...A WEAK BAND OF LAKE EFFECT SNOW WAS IMPINGING ON
NORTHWEST LAKE COUNTY AND FAR SOUTHEAST COOK COUNTY. BAND WAS
HEAVIER FOR A TIME LATE LAST EVENING...WITH SOME ACCUMULATION NOTED
ON WEB CAMS ALONG THE INTERSTATES. RADAR RETURNS HAVE WEAKENED
CONSIDERABLY...AND HIGH RES MODEL GUIDANCE SEEMS TO HAVE CAPTURED
THIS TREND NICELY. BOTH RUC AND NAM DO INDICATE THAT SLIGHT COOLING
AROUND 900 HPA MAY SLIGHTLY IMPROVE THE LOW-LEVEL THERMODYNAMIC
PROFILE AROUND 12Z THIS MORNING...BEFORE EQUILIBRIUM HEIGHTS LOWER
BELOW 4000 FT AND LOW LEVEL WINDS BACK AROUND TO THE NORTHWEST BY
MIDDAY. THEREFORE EXPECT LIGHT SNOW SHOWERS TO CONTINUE THROUGH MID
MORNING...SHIFTING EAST AND WEAKENING WITH TIME IN THE 15-18Z
PERIOD. CURRENT WEB CAM VIEWS FROM 80/94 NEAR HAMMOND INDICATE
CURRENT ACTIVITY HAVING LITTLE/NO IMPACT ON VISIBILITY AT 330
AM...AND HAVE ONLY INCLUDED AN ADDITIONAL TENTH OF AN INCH OF
SNOWFALL THIS MORNING MAINLY ACROSS NORTHERN LAKE COUNTY...THOUGH
WILL MONITOR FOR ANY SIGNS OF BETTER DEVELOPMENT PRIOR TO SUNRISE.

GOES 11-3.9 MICRON IMAGERY SHOWS CLEARING OF LOW CLOUDS WAS
OCCURRING ACROSS FAR NORTHWEST IL EARLY THIS MORNING...THOUGH LOW
CLOUDS STRETCHED BACK ACROSS A LARGE PORTION OF CENTRAL IA. A SHORT
WAVE TROUGH DIGGING SOUTHEAST ACROSS THE HAWKEYE STATE MAY SLOW
CLEARING FOR A TIME THIS MORNING...BEFORE THE MID-LEVEL VORT AND
TROUGH AXIS PASS INTO CENTRAL IL EARLY THIS AFTERNOON. DRIER LOW
LEVEL AIR JUST UPSTREAM WILL ADVECT INTO THE AREA FROM THE NORTHWEST
HOWEVER WHICH SHOULD ALLOW CLEARING FROM THE NORTH/NORTHWEST THROUGH
THE DAY...WITH SOUTHEASTERN COUNTIES CLEARING LAST. MODEL
TIME/HEIGHT SECTIONS THEN APPEAR QUITE DRY TONIGHT THROUGH THURSDAY.
TEMPERATURE GUIDANCE IN FAIRLY CLOSE AGREEMENT DURING THIS PERIOD
AND GENERALLY USED A BLEND LEANING A LITTLE TOWARD THE COOLER
NUMBERS TODAY...AND TOWARD THE WARMER END OF THE RANGE WITH MORE SUN
AND WEAK WARM ADVECTION DEVELOPING THURSDAY.

GUIDANCE CONTINUES TO DEPICT SIGNIFICANT AMPLIFICATION OF THE UPPER
FLOW FOR THE END OF THE WEEK...WITH LARGE TROUGH DEVELOPING OVER
MUCH OF EASTERN NORTH AMERICA AND AT LEAST A TEMPORARY PUSH OF
ARCTIC AIR. MAIN AREA OF LOW PRESSURE IS PROGGED TO DEVELOP JUST
NORTH OF LAKE SUPERIOR ON THURSDAY AHEAD OF MID-LEVEL SHORT WAVE...
WITH UPPER WAVE AND SURFACE COLD FRONT PUSHING ACROSS THE FORECAST
AREA EARLY FRIDAY. MODELS INDICATE CONSIDERABLE DRY AIR IN THE
850-650 HPA LAYER PRECLUDING MUCH OF A PRECIPITATION THREAT...THOUGH
FAIRLY STRONG ISENTROPIC ASCENT IN THE WARM ADVECTION AHEAD OF THE
TROUGH MAY RESULT IN ENOUGH SATURATION IN THE 280-285 K LAYER TO
PRODUCE SOME FLURRIES FRIDAY MORNING. STRONG COLD ADVECTION ON
BLUSTERY NORTHERLY WINDS FRIDAY WILL LIKELY PRODUCE FALLING DAYTIME
TEMPS INTO THE 20S...WITH 850 HPA TEMPS FROM GFS/ECMWF DEPICTING -17
TO -19 C OVER THE AREA BY 12Z SATURDAY.

BESIDES THE COLD...THE REAL FORECAST CONCERN IN THE FRIDAY-SATURDAY
PERIOD IS THE POTENTIAL FOR LAKE EFFECT SNOW INTO NORTHEAST IL AND
NORTHWEST INDIANA. LAKE SURFACE TO 850 HPA DELTAS INCREASE INTO THE
LOW 20S LATE FRIDAY THROUGH SATURDAY MORNING...DURING A PERIOD IN
WHICH THE LOW LEVEL WINDS WILL BE NORTH-NORTHEAST DOWN THE FULL
FETCH OF THE LAKE. FORECAST SOUNDINGS INDICATE EQUILIBRIUM LEVELS
RISING TO NEAR 9000 FT BY 12Z SATURDAY...WITH LAKE INDUCED CAPES OF
400-500 J/KG. THIS WOULD SUGGEST THE POTENTIAL FOR SOME SIGNIFICANT
ACCUMULATING LAKE EFFECT FROM FRIDAY AFTERNOON THROUGH SATURDAY
MORNING. ONLY LIMITING FACTOR WOULD BE THE VERY DRY ARCTIC AIR
SPREADING ACROSS THE WESTERN LAKES...THOUGH THE LONG FETCH WILL
LIKELY PROVIDE ENOUGH MOISTURE FLUX TO MAKE UP FOR THE DRYNESS OF
THE AIRMASS. WILL BE INTERESTING TO SEE SOME OF THE HIGH RESOLUTION
GUIDANCE AS THE FRIDAY-SATURDAY PERIOD APPROACHES. FOR NOW HAVE
INCREASED POPS FOR THE LAKESIDE COUNTIES...AND WILL HIGHLIGHT
POTENTIAL FOR ACCUMULATING LAKE SNOWS IN THE HAZARDOUS WEATHER
OUTLOOK.

LONGER RANGE GUIDANCE IN A LITTLE BETTER AGREEMENT IN SHIFTING UPPER
TROUGH OFF TO THE EAST SUNDAY...AND BUILDING SURFACE HIGH PRESSURE
RIDGE IN FROM THE WEST SUNDAY NIGHT. WARM ADVECTION WORKS TO PUSH
THE ARCTIC AIR AWAY MONDAY AS LOW LEVEL WINDS SHIFT TO THE SOUTH.
BOTH OPERATIONAL ECMWF AND GFS INDICATE A SHORT WAVE LIFTING
NORTHEAST ACROSS THE REGION LATE MONDAY SUGGESTING POTENTIAL FOR
SOME LIGHT SNOW MONDAY NIGHT INTO TUESDAY...WITH TEMPS CLIMBING A
BIT BACK ABOVE NORMAL.

RATZER

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 14Z...

* NONE.

KJB

//DISCUSSION...UPDATED 12Z...

HIGH PRESSURE BUILDING ACROSS THE AREA WILL PROVIDE RELATIVELY QUIET
WEATHER AND WILL EVENTUALLY CLEAR OUT CLOUD COVER. THIS MORNING...
LOW LEVEL MOISTURE HAS VERY SLOWLY BEEN ERODING FROM THE NORTHWEST
NEARLY STALLING AT RFD. RUC GUIDANCE SUGGESTS THAT LOW CLOUDS MAY
LINGER INTO THE LATE MORNING OR EARLY AFTERNOON ACROSS THE CHICAGO
AREA...THUS OPTED TO SLOW CLEARING ACROSS ORD/MDW FOR SEVERAL
HOURS. STILL...THE CLOUD DECK HAS BEEN GRADUALLY IMPROVING THROUGH
THE NIGHT AND DO NOT EXPECT MVFR CONDITIONS TO RETURN. NORTHERLY
WINDS THIS MORNING WILL BACK TO THE WEST THROUGH THE DAY AS HIGH
PRESSURE SLIDES SOUTH OF THE FORECAST AREA. FEW LINGERING LAKE
EFFECT SNOW SHOWERS THIS MORNING ACROSS NORTHWEST INDIANA WILL
CONTINUE TO WEAKEN AND SHIFT FARTHER EAST AWAY FROM THE CHICAGO/NW
INDIANA TERMINALS AS WINDS BACK. BMD

//ORD AND MDW CONFIDENCE...UPDATED 14Z...

* HIGH CONFIDENCE ON ALL FORECAST ELEMENTS.

KJB

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

THURSDAY NIGHT...VFR.
FRIDAY/SATURDAY...CHC LAKE EFFECT SNOW WITH MVFR/IFR POSSIBLE.
SUNDAY/MONDAY...VFR.
TUESDAY...SLT CHC RAIN/SNOW.
BMD

&&

.MARINE...
315 AM CST

FOLLOWING THE PASSAGE OF A COLD FRONT AND WITH HIGH PRESSURE
BUILDING ACROSS THE NORTHERN PLAINS AND UPPER MISSISIPPI
VALLEY...WINDS WILL GRADUALLY DIMINISH. AS THE HIGH PRESSURE SAGS
TO THE SOUTHEAST WEDNESDAY AND THURSDAY...WINDS WILL BECOME
WESTERLY TO 25KT AND EVENTUALLY SOUTHWESTERLY...AS ANOTHER ARCTIC
COLD FRONT APPROACHES. THIS FRONT WILL PUSH ACROSS THE LAKE
THURSDAY NIGHT. A STRONG PUSH OF COLD AIR MAY BRING WINDS UP TO
GALE FORCE OVER THE FAR NORTHERN PORTIONS OF THE LAKE LATE
THURSDAY INTO THURSDAY NIGHT.

KREIN

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
     UNTIL 11 AM WEDNESDAY.

&&

$$






AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 526 AM CST WED FEB 8 2012

.DISCUSSION...
356 AM CST

NEAR TERM CONCERNS THIS MORNING INCLUDE LIGHT SNOW ACROSS SOUTHERN
PARTS OF THE CWA...LINGERING LIGHT LAKE EFFECT SNOW THIS MORNING
OVER NORTHERN LAKE AND PORTER COUNTIES...AND CLOUD TRENDS ACROSS THE
AREA TODAY. LOOMING ON THE HORIZON IS A PUNCH OF ARCTIC AIR WHICH
ARRIVES FRIDAY...WITH THE FOCUS ON COLDER TEMPS AND THE POTENTIAL
FOR MORE SIGNIFICANT LAKE EFFECT SNOW ACROSS NORTHEAST IL AND
NORTHWEST INDIANA INTO SATURDAY.

LIGHT SNOW WAS OCCURRING EARLY THIS MORNING GENERALLY SOUTH OF A VYS
TO VPZ LINE...IN ASSOCIATION WITH AN UPPER DISTURBANCE MOVING ACROSS
DOWNSTATE IL INTO THE LOWER OHIO VALLEY. STRONGEST FORCING WITH THIS
SYSTEM WAS OCCURRING SOUTH OF THE CWA...WITH SFC OBS ACROSS OUR
SOUTHERN COUNTIES INDICATING  VISIBILITIES GENERALLY IN THE 3-7SM
RANGE AND SUGGESTING ONLY MINOR ACCUMULATIONS. LIGHT SNOW WILL
CONTINUE ACROSS THE SOUTH THIS MORNING...SHIFTING MAINLY EAST OF
INTERSTATE 57 BY 12Z. LITTLE ADDITIONAL ACCUMULATION IS EXPECTED.

FARTHER NORTH...A WEAK BAND OF LAKE EFFECT SNOW WAS IMPINGING ON
NORTHWEST LAKE COUNTY AND FAR SOUTHEAST COOK COUNTY. BAND WAS
HEAVIER FOR A TIME LATE LAST EVENING...WITH SOME ACCUMULATION NOTED
ON WEB CAMS ALONG THE INTERSTATES. RADAR RETURNS HAVE WEAKENED
CONSIDERABLY...AND HIGH RES MODEL GUIDANCE SEEMS TO HAVE CAPTURED
THIS TREND NICELY. BOTH RUC AND NAM DO INDICATE THAT SLIGHT COOLING
AROUND 900 HPA MAY SLIGHTLY IMPROVE THE LOW-LEVEL THERMODYNAMIC
PROFILE AROUND 12Z THIS MORNING...BEFORE EQUILIBRIUM HEIGHTS LOWER
BELOW 4000 FT AND LOW LEVEL WINDS BACK AROUND TO THE NORTHWEST BY
MIDDAY. THEREFORE EXPECT LIGHT SNOW SHOWERS TO CONTINUE THROUGH MID
MORNING...SHIFTING EAST AND WEAKENING WITH TIME IN THE 15-18Z
PERIOD. CURRENT WEB CAM VIEWS FROM 80/94 NEAR HAMMOND INDICATE
CURRENT ACTIVITY HAVING LITTLE/NO IMPACT ON VISIBILITY AT 330
AM...AND HAVE ONLY INCLUDED AN ADDITIONAL TENTH OF AN INCH OF
SNOWFALL THIS MORNING MAINLY ACROSS NORTHERN LAKE COUNTY...THOUGH
WILL MONITOR FOR ANY SIGNS OF BETTER DEVELOPMENT PRIOR TO SUNRISE.

GOES 11-3.9 MICRON IMAGERY SHOWS CLEARING OF LOW CLOUDS WAS
OCCURRING ACROSS FAR NORTHWEST IL EARLY THIS MORNING...THOUGH LOW
CLOUDS STRETCHED BACK ACROSS A LARGE PORTION OF CENTRAL IA. A SHORT
WAVE TROUGH DIGGING SOUTHEAST ACROSS THE HAWKEYE STATE MAY SLOW
CLEARING FOR A TIME THIS MORNING...BEFORE THE MID-LEVEL VORT AND
TROUGH AXIS PASS INTO CENTRAL IL EARLY THIS AFTERNOON. DRIER LOW
LEVEL AIR JUST UPSTREAM WILL ADVECT INTO THE AREA FROM THE NORTHWEST
HOWEVER WHICH SHOULD ALLOW CLEARING FROM THE NORTH/NORTHWEST THROUGH
THE DAY...WITH SOUTHEASTERN COUNTIES CLEARING LAST. MODEL
TIME/HEIGHT SECTIONS THEN APPEAR QUITE DRY TONIGHT THROUGH THURSDAY.
TEMPERATURE GUIDANCE IN FAIRLY CLOSE AGREEMENT DURING THIS PERIOD
AND GENERALLY USED A BLEND LEANING A LITTLE TOWARD THE COOLER
NUMBERS TODAY...AND TOWARD THE WARMER END OF THE RANGE WITH MORE SUN
AND WEAK WARM ADVECTION DEVELOPING THURSDAY.

GUIDANCE CONTINUES TO DEPICT SIGNIFICANT AMPLIFICATION OF THE UPPER
FLOW FOR THE END OF THE WEEK...WITH LARGE TROUGH DEVELOPING OVER
MUCH OF EASTERN NORTH AMERICA AND AT LEAST A TEMPORARY PUSH OF
ARCTIC AIR. MAIN AREA OF LOW PRESSURE IS PROGGED TO DEVELOP JUST
NORTH OF LAKE SUPERIOR ON THURSDAY AHEAD OF MID-LEVEL SHORT WAVE...
WITH UPPER WAVE AND SURFACE COLD FRONT PUSHING ACROSS THE FORECAST
AREA EARLY FRIDAY. MODELS INDICATE CONSIDERABLE DRY AIR IN THE
850-650 HPA LAYER PRECLUDING MUCH OF A PRECIPITATION THREAT...THOUGH
FAIRLY STRONG ISENTROPIC ASCENT IN THE WARM ADVECTION AHEAD OF THE
TROUGH MAY RESULT IN ENOUGH SATURATION IN THE 280-285 K LAYER TO
PRODUCE SOME FLURRIES FRIDAY MORNING. STRONG COLD ADVECTION ON
BLUSTERY NORTHERLY WINDS FRIDAY WILL LIKELY PRODUCE FALLING DAYTIME
TEMPS INTO THE 20S...WITH 850 HPA TEMPS FROM GFS/ECMWF DEPICTING -17
TO -19 C OVER THE AREA BY 12Z SATURDAY.

BESIDES THE COLD...THE REAL FORECAST CONCERN IN THE FRIDAY-SATURDAY
PERIOD IS THE POTENTIAL FOR LAKE EFFECT SNOW INTO NORTHEAST IL AND
NORTHWEST INDIANA. LAKE SURFACE TO 850 HPA DELTAS INCREASE INTO THE
LOW 20S LATE FRIDAY THROUGH SATURDAY MORNING...DURING A PERIOD IN
WHICH THE LOW LEVEL WINDS WILL BE NORTH-NORTHEAST DOWN THE FULL
FETCH OF THE LAKE. FORECAST SOUNDINGS INDICATE EQUILIBRIUM LEVELS
RISING TO NEAR 9000 FT BY 12Z SATURDAY...WITH LAKE INDUCED CAPES OF
400-500 J/KG. THIS WOULD SUGGEST THE POTENTIAL FOR SOME SIGNIFICANT
ACCUMULATING LAKE EFFECT FROM FRIDAY AFTERNOON THROUGH SATURDAY
MORNING. ONLY LIMITING FACTOR WOULD BE THE VERY DRY ARCTIC AIR
SPREADING ACROSS THE WESTERN LAKES...THOUGH THE LONG FETCH WILL
LIKELY PROVIDE ENOUGH MOISTURE FLUX TO MAKE UP FOR THE DRYNESS OF
THE AIRMASS. WILL BE INTERESTING TO SEE SOME OF THE HIGH RESOLUTION
GUIDANCE AS THE FRIDAY-SATURDAY PERIOD APPROACHES. FOR NOW HAVE
INCREASED POPS FOR THE LAKESIDE COUNTIES...AND WILL HIGHLIGHT
POTENTIAL FOR ACCUMULATING LAKE SNOWS IN THE HAZARDOUS WEATHER
OUTLOOK.

LONGER RANGE GUIDANCE IN A LITTLE BETTER AGREEMENT IN SHIFTING UPPER
TROUGH OFF TO THE EAST SUNDAY...AND BUILDING SURFACE HIGH PRESSURE
RIDGE IN FROM THE WEST SUNDAY NIGHT. WARM ADVECTION WORKS TO PUSH
THE ARCTIC AIR AWAY MONDAY AS LOW LEVEL WINDS SHIFT TO THE SOUTH.
BOTH OPERATIONAL ECMWF AND GFS INDICATE A SHORT WAVE LIFTING
NORTHEAST ACROSS THE REGION LATE MONDAY SUGGESTING POTENTIAL FOR
SOME LIGHT SNOW MONDAY NIGHT INTO TUESDAY...WITH TEMPS CLIMBING A
BIT BACK ABOVE NORMAL.

RATZER

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 12Z...

* TIMING CLEARING OF CIGS. BMD

//DISCUSSION...UPDATED 12Z...

HIGH PRESSURE BUILDING ACROSS THE AREA WILL PROVIDE RELATIVELY QUIET
WEATHER AND WILL EVENTUALLY CLEAR OUT CLOUD COVER. THIS MORNING...
LOW LEVEL MOISTURE HAS VERY SLOWLY BEEN ERODING FROM THE NORTHWEST
NEARLY STALLING AT RFD. RUC GUIDANCE SUGGESTS THAT LOW CLOUDS MAY
LINGER INTO THE LATE MORNING OR EARLY AFTERNOON ACROSS THE CHICAGO
AREA...THUS OPTED TO SLOW CLEARING ACROSS ORD/MDW FOR SEVERAL
HOURS. STILL...THE CLOUD DECK HAS BEEN GRADUALLY IMPROVING THROUGH
THE NIGHT AND DO NOT EXPECT MVFR CONDITIONS TO RETURN. NORTHERLY
WINDS THIS MORNING WILL BACK TO THE WEST THROUGH THE DAY AS HIGH
PRESSURE SLIDES SOUTH OF THE FORECAST AREA. FEW LINGERING LAKE
EFFECT SNOW SHOWERS THIS MORNING ACROSS NORTHWEST INDIANA WILL
CONTINUE TO WEAKEN AND SHIFT FARTHER EAST AWAY FROM THE CHICAGO/NW
INDIANA TERMINALS AS WINDS BACK. BMD


//ORD AND MDW CONFIDENCE...UPDATED 12Z...

* LOW TO MEDIUM CONFIDENCE ON TIMING LOW CIGS CLEARING THIS
  MORNING.
* HIGH CONFIDENCE ON ALL OTHER FORECAST ELEMENTS. BMD

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

THURSDAY NIGHT...VFR.
FRIDAY/SATURDAY...CHC LAKE EFFECT SNOW WITH MVFR/IFR POSSIBLE.
SUNDAY/MONDAY...VFR.
TUESDAY...SLT CHC RAIN/SNOW.
BMD

&&

.MARINE...
315 AM CST

FOLLOWING THE PASSAGE OF A COLD FRONT AND WITH HIGH PRESSURE
BUILDING ACROSS THE NORTHERN PLAINS AND UPPER MISSISIPPI
VALLEY...WINDS WILL GRADUALLY DIMINISH. AS THE HIGH PRESSURE SAGS
TO THE SOUTHEAST WEDNESDAY AND THURSDAY...WINDS WILL BECOME
WESTERLY TO 25KT AND EVENTUALLY SOUTHWESTERLY...AS ANOTHER ARCTIC
COLD FRONT APPROACHES. THIS FRONT WILL PUSH ACROSS THE LAKE
THURSDAY NIGHT. A STRONG PUSH OF COLD AIR MAY BRING WINDS UP TO
GALE FORCE OVER THE FAR NORTHERN PORTIONS OF THE LAKE LATE
THURSDAY INTO THURSDAY NIGHT.

KREIN

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
     UNTIL 11 AM WEDNESDAY.

&&

$$





AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 359 AM CST WED FEB 8 2012

.DISCUSSION...
356 AM CST

NEAR TERM CONCERNS THIS MORNING INCLUDE LIGHT SNOW ACROSS SOUTHERN
PARTS OF THE CWA...LINGERING LIGHT LAKE EFFECT SNOW THIS MORNING
OVER NORTHERN LAKE AND PORTER COUNTIES...AND CLOUD TRENDS ACROSS THE
AREA TODAY. LOOMING ON THE HORIZON IS A PUNCH OF ARCTIC AIR WHICH
ARRIVES FRIDAY...WITH THE FOCUS ON COLDER TEMPS AND THE POTENTIAL
FOR MORE SIGNIFICANT LAKE EFFECT SNOW ACROSS NORTHEAST IL AND
NORTHWEST INDIANA INTO SATURDAY.

LIGHT SNOW WAS OCCURRING EARLY THIS MORNING GENERALLY SOUTH OF A VYS
TO VPZ LINE...IN ASSOCIATION WITH AN UPPER DISTURBANCE MOVING ACROSS
DOWNSTATE IL INTO THE LOWER OHIO VALLEY. STRONGEST FORCING WITH THIS
SYSTEM WAS OCCURRING SOUTH OF THE CWA...WITH SFC OBS ACROSS OUR
SOUTHERN COUNTIES INDICATING  VISIBILITIES GENERALLY IN THE 3-7SM
RANGE AND SUGGESTING ONLY MINOR ACCUMULATIONS. LIGHT SNOW WILL
CONTINUE ACROSS THE SOUTH THIS MORNING...SHIFTING MAINLY EAST OF
INTERSTATE 57 BY 12Z. LITTLE ADDITIONAL ACCUMULATION IS EXPECTED.

FARTHER NORTH...A WEAK BAND OF LAKE EFFECT SNOW WAS IMPINGING ON
NORTHWEST LAKE COUNTY AND FAR SOUTHEAST COOK COUNTY. BAND WAS
HEAVIER FOR A TIME LATE LAST EVENING...WITH SOME ACCUMULATION NOTED
ON WEB CAMS ALONG THE INTERSTATES. RADAR RETURNS HAVE WEAKENED
CONSIDERABLY...AND HIGH RES MODEL GUIDANCE SEEMS TO HAVE CAPTURED
THIS TREND NICELY. BOTH RUC AND NAM DO INDICATE THAT SLIGHT COOLING
AROUND 900 HPA MAY SLIGHTLY IMPROVE THE LOW-LEVEL THERMODYNAMIC
PROFILE AROUND 12Z THIS MORNING...BEFORE EQUILIBRIUM HEIGHTS LOWER
BELOW 4000 FT AND LOW LEVEL WINDS BACK AROUND TO THE NORTHWEST BY
MIDDAY. THEREFORE EXPECT LIGHT SNOW SHOWERS TO CONTINUE THROUGH MID
MORNING...SHIFTING EAST AND WEAKENING WITH TIME IN THE 15-18Z
PERIOD. CURRENT WEB CAM VIEWS FROM 80/94 NEAR HAMMOND INDICATE
CURRENT ACTIVITY HAVING LITTLE/NO IMPACT ON VISIBILITY AT 330
AM...AND HAVE ONLY INCLUDED AN ADDITIONAL TENTH OF AN INCH OF
SNOWFALL THIS MORNING MAINLY ACROSS NORTHERN LAKE COUNTY...THOUGH
WILL MONITOR FOR ANY SIGNS OF BETTER DEVELOPMENT PRIOR TO SUNRISE.

GOES 11-3.9 MICRON IMAGERY SHOWS CLEARING OF LOW CLOUDS WAS
OCCURRING ACROSS FAR NORTHWEST IL EARLY THIS MORNING...THOUGH LOW
CLOUDS STRETCHED BACK ACROSS A LARGE PORTION OF CENTRAL IA. A SHORT
WAVE TROUGH DIGGING SOUTHEAST ACROSS THE HAWKEYE STATE MAY SLOW
CLEARING FOR A TIME THIS MORNING...BEFORE THE MID-LEVEL VORT AND
TROUGH AXIS PASS INTO CENTRAL IL EARLY THIS AFTERNOON. DRIER LOW
LEVEL AIR JUST UPSTREAM WILL ADVECT INTO THE AREA FROM THE NORTHWEST
HOWEVER WHICH SHOULD ALLOW CLEARING FROM THE NORTH/NORTHWEST THROUGH
THE DAY...WITH SOUTHEASTERN COUNTIES CLEARING LAST. MODEL
TIME/HEIGHT SECTIONS THEN APPEAR QUITE DRY TONIGHT THROUGH THURSDAY.
TEMPERATURE GUIDANCE IN FAIRLY CLOSE AGREEMENT DURING THIS PERIOD
AND GENERALLY USED A BLEND LEANING A LITTLE TOWARD THE COOLER
NUMBERS TODAY...AND TOWARD THE WARMER END OF THE RANGE WITH MORE SUN
AND WEAK WARM ADVECTION DEVELOPING THURSDAY.

GUIDANCE CONTINUES TO DEPICT SIGNIFICANT AMPLIFICATION OF THE UPPER
FLOW FOR THE END OF THE WEEK...WITH LARGE TROUGH DEVELOPING OVER
MUCH OF EASTERN NORTH AMERICA AND AT LEAST A TEMPORARY PUSH OF
ARCTIC AIR. MAIN AREA OF LOW PRESSURE IS PROGGED TO DEVELOP JUST
NORTH OF LAKE SUPERIOR ON THURSDAY AHEAD OF MID-LEVEL SHORT WAVE...
WITH UPPER WAVE AND SURFACE COLD FRONT PUSHING ACROSS THE FORECAST
AREA EARLY FRIDAY. MODELS INDICATE CONSIDERABLE DRY AIR IN THE
850-650 HPA LAYER PRECLUDING MUCH OF A PRECIPITATION THREAT...THOUGH
FAIRLY STRONG ISENTROPIC ASCENT IN THE WARM ADVECTION AHEAD OF THE
TROUGH MAY RESULT IN ENOUGH SATURATION IN THE 280-285 K LAYER TO
PRODUCE SOME FLURRIES FRIDAY MORNING. STRONG COLD ADVECTION ON
BLUSTERY NORTHERLY WINDS FRIDAY WILL LIKELY PRODUCE FALLING DAYTIME
TEMPS INTO THE 20S...WITH 850 HPA TEMPS FROM GFS/ECMWF DEPICTING -17
TO -19 C OVER THE AREA BY 12Z SATURDAY.

BESIDES THE COLD...THE REAL FORECAST CONCERN IN THE FRIDAY-SATURDAY
PERIOD IS THE POTENTIAL FOR LAKE EFFECT SNOW INTO NORTHEAST IL AND
NORTHWEST INDIANA. LAKE SURFACE TO 850 HPA DELTAS INCREASE INTO THE
LOW 20S LATE FRIDAY THROUGH SATURDAY MORNING...DURING A PERIOD IN
WHICH THE LOW LEVEL WINDS WILL BE NORTH-NORTHEAST DOWN THE FULL
FETCH OF THE LAKE. FORECAST SOUNDINGS INDICATE EQUILIBRIUM LEVELS
RISING TO NEAR 9000 FT BY 12Z SATURDAY...WITH LAKE INDUCED CAPES OF
400-500 J/KG. THIS WOULD SUGGEST THE POTENTIAL FOR SOME SIGNIFICANT
ACCUMULATING LAKE EFFECT FROM FRIDAY AFTERNOON THROUGH SATURDAY
MORNING. ONLY LIMITING FACTOR WOULD BE THE VERY DRY ARCTIC AIR
SPREADING ACROSS THE WESTERN LAKES...THOUGH THE LONG FETCH WILL
LIKELY PROVIDE ENOUGH MOISTURE FLUX TO MAKE UP FOR THE DRYNESS OF
THE AIRMASS. WILL BE INTERESTING TO SEE SOME OF THE HIGH RESOLUTION
GUIDANCE AS THE FRIDAY-SATURDAY PERIOD APPROACHES. FOR NOW HAVE
INCREASED POPS FOR THE LAKESIDE COUNTIES...AND WILL HIGHLIGHT
POTENTIAL FOR ACCUMULATING LAKE SNOWS IN THE HAZARDOUS WEATHER
OUTLOOK.

LONGER RANGE GUIDANCE IN A LITTLE BETTER AGREEMENT IN SHIFTING UPPER
TROUGH OFF TO THE EAST SUNDAY...AND BUILDING SURFACE HIGH PRESSURE
RIDGE IN FROM THE WEST SUNDAY NIGHT. WARM ADVECTION WORKS TO PUSH
THE ARCTIC AIR AWAY MONDAY AS LOW LEVEL WINDS SHIFT TO THE SOUTH.
BOTH OPERATIONAL ECMWF AND GFS INDICATE A SHORT WAVE LIFTING
NORTHEAST ACROSS THE REGION LATE MONDAY SUGGESTING POTENTIAL FOR
SOME LIGHT SNOW MONDAY NIGHT INTO TUESDAY...WITH TEMPS CLIMBING A
BIT BACK ABOVE NORMAL.

RATZER

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 10Z...

* TIMING CLEARING OF 025-045 VFR CIGS.

BMD

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

LAKE EFFECT SNOW HAS FINALLY MOVED ASHORE AND FLURRIES HAVE MOVED
OVER MDW. NOT EXPECTING ANY SNOW ACCUMULATION FROM THESE
FLURRIES...AND CIGS SHOULD REMAIN ABOVE 015. BASED ON RADAR
TRENDS...THINKING FLURRIES WILL BE SOUTH OF MDW BY 06Z. A MORE
IMPRESSIVE LOOKING LAKE EFFECT SNOW SHOWER BAND HAS FORMED OVER
GARY INDIANA. THINKING THE BAND WILL ONLY PERSIST FOR THE NEXT
COUPLE OF HOURS.

WIND GUSTS HAVE DIMINISHED AS THE PRESSURE GRADIENT OVERHEAD HAS
ALSO WEAKENED. WINDS WILL REMAIN NORTHWESTERLY TONIGHT AND THEN
TURN WESTERLY AS THE HIGH PRESSURE MOVES TOWARD OUR AREA. CIGS
WILL AS BE IMPROVING AS THE HIGH APPROACHES. SKIES ARE CLEARING
IN SOUTHERN WISCONSIN...BUT CANNOT CLEARLY IDENTIFY THE CLEARING
LINE ON SATELLITE IMAGERY DUE TO HIGH LEVEL CIRRUS. THINKING RFD
WILL REACH VFR BY 08Z...AND OTHER SITES MAY GO VFR SOONER THAN
FORECAST. GYY WILL STAY MVFR THE LONGEST AS LAKE EFFECT CLOUDS
WILL PERSIST THROUGH THE EARLY MORNING HOURS. SKIES WILL CLEAR OUT
COMPLETELY LATE WEDNESDAY.

JEE

//ORD AND MDW CONFIDENCE...UPDATED 10Z...

* LOW TO MEDIUM CONFIDENCE ON TIMING 025-045 CIGS CLEARING THIS
  MORNING...MOISTURE MAY LINGER UNTIL AFTER DAYBREAK.
* HIGH CONFIDENCE ON ALL OTHER FORECAST ELEMENTS. BMD

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

THURSDAY...VFR.

FRIDAY...MVFR/IFR POSSIBLE.

SATURDAY THROUGH MONDAY...VFR.

JEE

&&

.MARINE...
315 AM CST

FOLLOWING THE PASSAGE OF A COLD FRONT AND WITH HIGH PRESSURE
BUILDING ACROSS THE NORTHERN PLAINS AND UPPER MISSISIPPI
VALLEY...WINDS WILL GRADUALLY DIMINISH. AS THE HIGH PRESSURE SAGS
TO THE SOUTHEAST WEDNESDAY AND THURSDAY...WINDS WILL BECOME
WESTERLY TO 25KT AND EVENTUALLY SOUTHWESTERLY...AS ANOTHER ARCTIC
COLD FRONT APPROACHES. THIS FRONT WILL PUSH ACROSS THE LAKE
THURSDAY NIGHT. A STRONG PUSH OF COLD AIR MAY BRING WINDS UP TO
GALE FORCE OVER THE FAR NORTHERN PORTIONS OF THE LAKE LATE
THURSDAY INTO THURSDAY NIGHT.

KREIN

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
     UNTIL 11 AM WEDNESDAY.

&&

$$





AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 357 AM CST WED FEB 8 2012

.DISCUSSION...
356 AM CST

NEAR TERM CONCERNS THIS MORNING INCLUDE LIGHT SNOW ACROSS SOUTHERN
PARTS OF THE CWA...LINGERING LIGHT LAKE EFFECT SNOW THIS MORNING
OVER NORTHERN LAKE AND PORTER COUNTIES...AND CLOUD TRENDS ACROSS THE
AREA TODAY. LOOMING ON THE HORIZON IS A PUNCH OF ARCTIC AIR WHICH
ARRIVES FRIDAY...WITH THE FOCUS ON COLDER TEMPS AND THE POTENTIAL
FOR MORE SIGNIFICANT LAKE EFFECT SNOW ACROSS NORTHEAST IL AND
NORTHWEST INDIANA INTO SATURDAY.

LIGHT SNOW WAS OCCURRING EARLY THIS MORNING GENERALLY SOUTH OF A VYS
TO VPZ LINE...IN ASSOCIATION WITH AN UPPER DISTURBANCE MOVING ACROSS
DOWNSTATE IL INTO THE LOWER OHIO VALLEY. STRONGEST FORCING WITH THIS
SYSTEM WAS OCCURRING SOUTH OF THE CWA...WITH SFC OBS ACROSS OUR
SOUTHERN COUNTIES INDICATING  VISIBILITIES GENERALLY IN THE 3-7SM
RANGE AND SUGGESTING ONLY MINOR ACCUMULATIONS. LIGHT SNOW WILL
CONTINUE ACROSS THE SOUTH THIS MORNING...SHIFTING MAINLY EAST OF
INTERSTATE 57 BY 12Z. LITTLE ADDITIONAL ACCUMULATION IS EXPECTED.

FARTHER NORTH...A WEAK BAND OF LAKE EFFECT SNOW WAS IMPINGING ON
NORTHWEST LAKE COUNTY AND FAR SOUTHEAST COOK COUNTY. BAND WAS
HEAVIER FOR A TIME LATE LAST EVENING...WITH SOME ACCUMULATION NOTED
ON WEB CAMS ALONG THE INTERSTATES. RADAR RETURNS HAVE WEAKENED
CONSIDERABLY...AND HIGH RES MODEL GUIDANCE SEEMS TO HAVE CAPTURED
THIS TREND NICELY. BOTH RUC AND NAM DO INDICATE THAT SLIGHT COOLING
AROUND 900 HPA MAY SLIGHTLY IMPROVE THE LOW-LEVEL THERMODYNAMIC
PROFILE AROUND 12Z THIS MORNING...BEFORE EQUILIBRIUM HEIGHTS LOWER
BELOW 4000 FT AND LOW LEVEL WINDS BACK AROUND TO THE NORTHWEST BY
MIDDAY. THEREFORE EXPECT LIGHT SNOW SHOWERS TO CONTINUE THROUGH MID
MORNING...SHIFTING EAST AND WEAKENING WITH TIME IN THE 15-18Z
PERIOD. CURRENT WEB CAM VIEWS FROM 80/94 NEAR HAMMOND INDICATE
CURRENT ACTIVITY HAVING LITTLE/NO IMPACT ON VISIBILITY AT 330
AM...AND HAVE ONLY INCLUDED AN ADDITIONAL TENTH OF AN INCH OF
SNOWFALL THIS MORNING MAINLY ACROSS NORTHERN LAKE COUNTY...THOUGH
WILL MONITOR FOR ANY SIGNS OF BETTER DEVELOPMENT PRIOR TO SUNRISE.

GOES 11-3.9 MICRON IMAGERY SHOWS CLEARING OF LOW CLOUDS WAS
OCCURRING ACROSS FAR NORTHWEST IL EARLY THIS MORNING...THOUGH LOW
CLOUDS STRETCHED BACK ACROSS A LARGE PORTION OF CENTRAL IA. A SHORT
WAVE TROUGH DIGGING SOUTHEAST ACROSS THE HAWKEYE STATE MAY SLOW
CLEARING FOR A TIME THIS MORNING...BEFORE THE MID-LEVEL VORT AND
TROUGH AXIS PASS INTO CENTRAL IL EARLY THIS AFTERNOON. DRIER LOW
LEVEL AIR JUST UPSTREAM WILL ADVECT INTO THE AREA FROM THE NORTHWEST
HOWEVER WHICH SHOULD ALLOW CLEARING FROM THE NORTH/NORTHWEST THROUGH
THE DAY...WITH SOUTHEASTERN COUNTIES CLEARING LAST. MODEL
TIME/HEIGHT SECTIONS THEN APPEAR QUITE DRY TONIGHT THROUGH THURSDAY.
TEMPERATURE GUIDANCE IN FAIRLY CLOSE AGREEMENT DURING THIS PERIOD
AND GENERALLY USED A BLEND LEANING A LITTLE TOWARD THE COOLER
NUMBERS TODAY...AND TOWARD THE WARMER END OF THE RANGE WITH MORE SUN
AND WEAK WARM ADVECTION DEVELOPING THURSDAY.

GUIDANCE CONTINUES TO DEPICT SIGNIFICANT AMPLIFICATION OF THE UPPER
FLOW FOR THE END OF THE WEEK...WITH LARGE TROUGH DEVELOPING OVER
MUCH OF EASTERN NORTH AMERICA AND AT LEAST A TEMPORARY PUSH OF
ARCTIC AIR. MAIN AREA OF LOW PRESSURE IS PROGGED TO DEVELOP JUST
NORTH OF LAKE SUPERIOR ON THURSDAY AHEAD OF MID-LEVEL SHORT WAVE...
WITH UPPER WAVE AND SURFACE COLD FRONT PUSHING ACROSS THE FORECAST
AREA EARLY FRIDAY. MODELS INDICATE CONSIDERABLE DRY AIR IN THE
850-650 HPA LAYER PRECLUDING MUCH OF A PRECIPITATION THREAT...THOUGH
FAIRLY STRONG ISENTROPIC ASCENT IN THE WARM ADVECTION AHEAD OF THE
TROUGH MAY RESULT IN ENOUGH SATURATION IN THE 280-285 K LAYER TO
PRODUCE SOME FLURRIES FRIDAY MORNING. STRONG COLD ADVECTION ON
BLUSTERY NORTHERLY WINDS FRIDAY WILL LIKELY PRODUCE FALLING DAYTIME
TEMPS INTO THE 20S...WITH 850 HPA TEMPS FROM GFS/ECMWF DEPICTING -17
TO -19 C OVER THE AREA BY 12Z SATURDAY.

BESIDES THE COLD...THE REAL FORECAST CONCERN IN THE FRIDAY-SATURDAY
PERIOD IS THE POTENTIAL FOR LAKE EFFECT SNOW INTO NORTHEAST IL AND
NORTHWEST INDIANA. LAKE SURFACE TO 850 HPA DELTAS INCREASE INTO THE
LOW 20S LATE FRIDAY THROUGH SATURDAY MORNING...DURING A PERIOD IN
WHICH THE LOW LEVEL WINDS WILL BE NORTH-NORTHEAST DOWN THE FULL
FETCH OF THE LAKE. FORECAST SOUNDINGS INDICATE EQUILIBRIUM LEVELS
RISING TO NEAR 9000 FT BY 12Z SATURDAY...WITH LAKE INDUCED CAPES OF
400-500 J/KG. THIS WOULD SUGGEST THE POTENTIAL FOR SOME SIGNIFICANT
ACCUMULATING LAKE EFFECT FROM FRIDAY AFTERNOON THROUGH SATURDAY
MORNING. ONLY LIMITING FACTOR WOULD BE THE VERY DRY ARCTIC AIR
SPREADING ACROSS THE WESTERN LAKES...THOUGH THE LONG FETCH WILL
LIKELY PROVIDE ENOUGH MOISTURE FLUX TO MAKE UP FOR THE DRYNESS OF
THE AIRMASS. WILL BE INTERESTING TO SEE SOME OF THE HIGH RESOLUTION
GUIDANCE AS THE FRIDAY-SATURDAY PERIOD APPROACHES. FOR NOW HAVE
INCREASED POPS FOR THE LAKESIDE COUNTIES...AND WILL HIGHLIGHT
POTENTIAL FOR ACCUMULATING LAKE SNOWS IN THE HAZARDOUS WEATHER
OUTLOOK.

LONGER RANGE GUIDANCE IN A LITTLE BETTER AGREEMENT IN SHIFTING UPPER
TROUGH OFF TO THE EAST SUNDAY...AND BUILDING SURFACE HIGH PRESSURE
RIDGE IN FROM THE WEST SUNDAY NIGHT. WARM ADVECTION WORKS TO PUSH
THE ARCTIC AIR AWAY MONDAY AS LOW LEVEL WINDS SHIFT TO THE SOUTH.
BOTH OPERATIONAL ECMWF AND GFS INDICATE A SHORT WAVE LIFTING
NORTHEAST ACROSS THE REGION LATE MONDAY SUGGESTING POTENTIAL FOR
SOME LIGHT SNOW MONDAY NIGHT INTO TUESDAY...WITH TEMPS CLIMBING A
BIT BACK ABOVE NORMAL.

RATZER

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 08Z...

* TIMING CLEARING OF MVF/LOW VFR CIGS.

BMD

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

LAKE EFFECT SNOW HAS FINALLY MOVED ASHORE AND FLURRIES HAVE MOVED
OVER MDW. NOT EXPECTING ANY SNOW ACCUMULATION FROM THESE
FLURRIES...AND CIGS SHOULD REMAIN ABOVE 015. BASED ON RADAR
TRENDS...THINKING FLURRIES WILL BE SOUTH OF MDW BY 06Z. A MORE
IMPRESSIVE LOOKING LAKE EFFECT SNOW SHOWER BAND HAS FORMED OVER
GARY INDIANA. THINKING THE BAND WILL ONLY PERSIST FOR THE NEXT
COUPLE OF HOURS.

WIND GUSTS HAVE DIMINISHED AS THE PRESSURE GRADIENT OVERHEAD HAS
ALSO WEAKENED. WINDS WILL REMAIN NORTHWESTERLY TONIGHT AND THEN
TURN WESTERLY AS THE HIGH PRESSURE MOVES TOWARD OUR AREA. CIGS
WILL AS BE IMPROVING AS THE HIGH APPROACHES. SKIES ARE CLEARING
IN SOUTHERN WISCONSIN...BUT CANNOT CLEARLY IDENTIFY THE CLEARING
LINE ON SATELLITE IMAGERY DUE TO HIGH LEVEL CIRRUS. THINKING RFD
WILL REACH VFR BY 08Z...AND OTHER SITES MAY GO VFR SOONER THAN
FORECAST. GYY WILL STAY MVFR THE LONGEST AS LAKE EFFECT CLOUDS
WILL PERSIST THROUGH THE EARLY MORNING HOURS. SKIES WILL CLEAR OUT
COMPLETELY LATE WEDNESDAY.

JEE

//ORD AND MDW CONFIDENCE...UPDATED 08Z...

* MEDIUM CONFIDENCE ON TIMING 025-040 CIGS CLEARING THIS MORNING.
* HIGH CONFIDENCE ON ALL OTHER FORECAST ELEMENTS.

BMD

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

THURSDAY...VFR.

FRIDAY...MVFR/IFR POSSIBLE.

SATURDAY THROUGH MONDAY...VFR.

JEE

&&

.MARINE...
315 AM CST

FOLLOWING THE PASSAGE OF A COLD FRONT AND WITH HIGH PRESSURE
BUILDING ACROSS THE NORTHERN PLAINS AND UPPER MISSISIPPI
VALLEY...WINDS WILL GRADUALLY DIMINISH. AS THE HIGH PRESSURE SAGS
TO THE SOUTHEAST WEDNESDAY AND THURSDAY...WINDS WILL BECOME
WESTERLY TO 25KT AND EVENTUALLY SOUTHWESTERLY...AS ANOTHER ARCTIC
COLD FRONT APPROACHES. THIS FRONT WILL PUSH ACROSS THE LAKE
THURSDAY NIGHT. A STRONG PUSH OF COLD AIR MAY BRING WINDS UP TO
GALE FORCE OVER THE FAR NORTHERN PORTIONS OF THE LAKE LATE
THURSDAY INTO THURSDAY NIGHT.

KREIN

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
     UNTIL 11 AM WEDNESDAY.

&&

$$





AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 1015 AM EST WED FEB 8 2012

.UPDATE...
THE SYNOPSIS AND NEAR TERM SECTIONS HAVE BEEN UPDATED BELOW

&&

.SYNOPSIS...

A FEW DISTURBANCES WILL BRING SNOW TO CENTRAL INDIANA OVER THE
NEXT FEW DAYS. BRIEF RIDGING WILL BUILD INTO THE AREA THROUGH
TOMORROW BEFORE ANOTHER DISTURBANCE BRINGS THE NEXT ROUND OF SNOW
ON FRIDAY AND FRIDAY NIGHT. ACCUMULATIONS WILL BE MINIMAL THOUGH.
FURTHER OUT...A QUICK DISTURBANCE WILL PASS OVER CENTRAL INDIANA
AT THE BEGINNING OF NEXT WEEK...BUT THIS LOOKS TO BE MORE OF A
RAIN/SNOW EVENT.

&&

.NEAR TERM /REST OF TODAY/...

ACCUMULATING SNOW HAS PRETTY MUCH ENDED ACROSS CENTRAL
INDIANA...BUT FLURRIES LINGER ACROSS THE AREA. HAVE UPDATED POPS
AND WEATHER TO REFLECT THIS. FLURRIES SHOULD STILL END BY EARLY
AFTERNOON AS FORCING EXITS.

SATELLITE SHOWS SOME BREAKS IN THE CLOUDS ACROSS NORTHEAST INDIANA
AS WELL AS NORTHWEST ILLINOIS. HOWEVER THE BREAKS ACROSS ILLINOIS
ARE NOT GROWING...AND GENERAL TREND OF CLOUDS ACROSS NORTHERN
INDIANA IS FOR THEM TO FILL IN FROM WEST TO EAST. WITH A BIT OF
UPPER ENERGY STILL TO THE NORTHWEST...RECENT SATELLITE TRENDS...AND
TENDENCY OF LOW CLOUDS TO HANG TOUGH...HAVE WENT MORE PESSIMISTIC
WITH CLOUD COVER TODAY.

GIVEN THE ABOVE DO NOT EXPECT BIG RISES IN TEMPERATURES TODAY...SO
ONLY MADE MINOR TWEAKS TO HIGHS.

&&

.SHORT TERM /TONIGHT THROUGH FRIDAY/...

THE MAIN FOCUS OF THE SHORT TERM IS SNOW CHANCES ON FRIDAY/FRIDAY
NIGHT WITH A BROAD UPPER LEVEL LOW.

SKIES WILL BECOME CLEAR TONIGHT AS FLOW BECOMES MORE ZONAL. THIS
SHOULD ALLOW TEMPS TO FALL INTO THE LOWER 20S. AGAIN...WENT WITH A
MODEL BLEND. CLEAR SKIES AND DRY CONDITIONS WILL CONTINUE THROUGH
FRIDAY MORNING. HOWEVER...A BROAD UPPER LEVEL TROUGH WILL AFFECT
THE GREAT LAKES REGION ON FRIDAY...SPREADING SNOW INTO CENTRAL
INDIANA. THIS EVENT WILL BE QUICK JUST LIKE TODAY/S WITH THE BEST
LIFT MOVING THROUGH IN THE SATURDAY 00-06Z TIME FRAME.
HOWEVER...MOISTURE APPEARS LIMITED AT THIS TIME. SO...AMOUNTS
SHOULDN/T BE MUCH MORE THAN A HALF AN INCH WITH THE INITIAL BAND.
ADDITIONAL LAKE EFFECT SNOW SHOWERS ON SATURDAY COULD ADD AN
ADDITIONAL QUARTER TO HALF INCH TO THE TOTALS.

TEMPS WILL BE MILD ON THURSDAY WITH HIGHS STILL IN THE UPPER
30S/LOW 40S...AND LOWS IN THE 20S ON THURSDAY AND FRIDAY NIGHTS
DUE TO INCREASED CLOUD COVER. BUT...THEY WILL DECREASE SUBSTANTIALLY
BEHIND THIS DISTURBANCE AS DEEPER COLD AIR IS ABLE TO FILTER INTO
CENTRAL INDIANA.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...

COLDER PATTERN SETTING UP FOR THE WEEKEND AS SHARP UPPER TROUGH
DEVELOPS OVER THE EASTERN PART OF THE COUNTRY WITH DEEP POLAR VORTEX
PRESENT OVER QUEBEC. LINGERING SNOW SHOWERS AND FLURRIES LIKELY TO
STILL BE GOING OVER PORTIONS OF THE FORECAST AREA SATURDAY MORNING
AS THE TROUGH AXIS SHIFTS EAST. PRESENCE OF FAVORABLE N/NW LOW LEVEL
WIND FIELDS MAY PROVIDE FOR SOME LAKE ENHANCEMENT TO SNOW SHOWERS
INTO NORTHEAST PORTIONS OF THE FORECAST AREA SATURDAY MORNING.
EVENTUALLY DRIER AIR WILL BUILD IN SATURDAY AFTERNOON AND EVENING AS
WINDS BACK AND BROAD ARCTIC HIGH PRESSURE EXPANDS INTO THE OHIO
VALLEY. EXPECT TEMPS TO REMAIN IN THE 20S ON SATURDAY AS 850MB TEMPS
BOTTOM OUT AROUND -16C. LOWS IN THE TEENS ARE LIKELY SATURDAY NIGHT.

HIGH PRESSURE WILL MAINTAIN DRY WEATHER FOR CENTRAL INDIANA FOR
SUNDAY INTO EARLY NEXT WEEK WITH A SLOW RECOVERY IN TEMPERATURES AS
WARM ADVECTION COMMENCES IN THE LOWER LEVELS. HIGHS SHOULD WARM BACK
INTO THE MID AND UPPER 30S BY MONDAY. UNSETTLED WEATHER RETURNING
FOR THE END OF THE EXTENDED AS UPPER LEVEL RIDGE BUCKLES TO EAST AND
IS REPLACED BY AN UPPER LEVEL DISTURBANCE MONDAY NIGHT. ECMWF...OP
GFS AND GGEM IN RELATIVELY GOOD AGREEMENT WITH JUST SUBTLE TIMING
DIFFERENCES REGARDING TRACK OF THIS SYSTEM. WILL CARRY LOW CHANCE
POPS AS LIGHT PRECIPITATION IMPACTS THE FORECAST AREA MONDAY NIGHT
AND TUESDAY. PRECIP TYPE IS MURKIER AS SURFACE TEMPS MAY SNEAK BELOW
FREEZING WITH WARMER AIR ALOFT. CARRYING A RA/SN MIX MONDAY NIGHT
WITH A SHIFT TO MAINLY RAIN TUESDAY AS LOWER LEVEL THICKNESSES WARM
ENOUGH TO SUPPORT. MORE SUBSTANTIAL UPPER LEVEL SYSTEM WILL LIFT
INTO THE OHIO VALLEY ON WEDNESDAY/THURSDAY WITH A CHANCE FOR MORE
WIDESPREAD PRECIPITATION.

&&

.AVIATION /DISCUSSION FOR 081500Z TAF UPDATES/...

KEPT IFR CONDITIONS IN AT BMG THROUGH 17Z AND HUF THROUGH 16Z BASED
ON TRENDS AND THEN MVFR AFTER. MEANWHILE...ALTHOUGH IND AND LAF HAVE
BRIEFLY JUMPED TO VFR...UPSTREAM OBS SUGGEST A RETURN TO MVFR.

PREVIOUS DISCUSSION FOLLOWS...

IFR AND LOWER CONDITIONS THIS MORNING IN LIGHT SNOW...MVFR
CEILINGS THROUGH THIS EVENING.

UPPER LEVEL DISTURBANCE TRAVERSING THE REGION EARLY THIS MORNING
WITH LIGHT SNOW ACROSS CENTRAL INDIANA. VISIBILITIES HAVE BEEN
1-2SM IN HEAVIEST RETURNS WITH CEILINGS AT 400-1000FT AT THE FOUR
TERMINALS. HRRR AND RUC BOTH MOVE THE SNOW EAST OF THE TERMINALS
BY 15Z AND CURRENT RADAR TRENDS SUPPORT THIS TIMING. VISIBILITIES
WILL RECOVER TO MVFR PRIOR TO THE SNOW ENDING.

MODEL SOUNDINGS AND LOW LEVEL RH PROGS INDICATE MVFR STRATOCU WILL
PERSIST FOR THE REMAINDER OF THE DAY WITH LIGHT N/NW FLOW. CLOUDS
NOT LIKELY TO SCATTER UNTIL TRAILING SHORTWAVE PASSES TO THE EAST
THIS EVENING. SURFACE HIGH PRESSURE WITH DEEP SUBSIDENCE WILL
ENABLE CLEARING SKIES LATE. DRIER AIRMASS SHOULD PRECLUDE ANY FOG
FORMATION AT TERMINALS LATE TONIGHT AS WELL. WINDS WILL BACK TO
LIGHT W/NW OVERNIGHT.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...TDUD/50
NEAR TERM...50
SHORT TERM...TDUD
LONG TERM....RYAN
AVIATION...RYAN/MK





AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 959 AM EST WED FEB 8 2012

.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...

A FEW DISTURBANCES WILL BRING SNOW TO CENTRAL INDIANA OVER THE
NEXT FEW DAYS. THE FIRST ONE WILL BE MOVING OUT OF THE AREA BY
LATE MORNING TODAY...BUT EXPECT LIGHT SNOW TO FALL UNTIL THEN
THIS MORNING. BRIEF RIDGING WILL THEN BUILD INTO THE AREA THROUGH
TOMORROW BEFORE ANOTHER DISTURBANCE BRINGS THE NEXT ROUND OF SNOW
ON FRIDAY AND FRIDAY NIGHT. ACCUMULATIONS WILL BE MINIMAL THOUGH
WITH BOTH EVENTS. FURTHER OUT...A QUICK DISTURBANCE WILL PASS OVER
CENTRAL INDIANA AT THE BEGINNING OF NEXT WEEK...BUT THIS LOOKS TO
BE MORE OF A RAIN/SNOW EVENT.

&&

.NEAR TERM /THIS MORNING AND TODAY/...

THE MAIN FOCUS OF THE NEAR TERM IS THE SNOW THIS MORNING.

CURRENT RADAR MOSAIC IS SHOWING WIDESPREAD PRECIP OVER MOST OF
CENTRAL INDIANA...WHICH IS FALLING IN THE FORM OF SNOW. CURRENT
ACTIVITY SHOULD BE THE MAIN SHOW FOR THIS PARTICULAR
DISTURBANCE...TAPERING OFF BY MID MORNING AS UPPER LEVEL LOW MOVES
EAST OF FORECAST AREA. SPS HAS BEEN ISSUED TO HIGHLIGHT IMPACTS
FOR MORNING RUSH HOUR. NO ADJUSTMENTS WERE MADE TO PREVIOUS
FORECAST AMOUNTS. STILL ANTICIPATE AMOUNTS LESS THAN INCH...WITH
LESSER AMOUNTS TO THE NORTH.

AS MENTIONED ABOVE...THIS WILL BE A QUICK EVENT WITH SNOW OUT OF
AREA BY LATE MORNING. NONETHELESS...SKIES WILL REMAIN MOSTLY
CLOUDY ALL DAY...WHICH WILL HINDER TEMPS. HIGHS WILL TOP OFF IN
THE MID TO UPPER 30S...FELT ALL BLEND WAS THE WAY TO GO SINCE THERE
WAS LITTLE DISCREPANCY IN MODELS.

LATEST OBS ARE SHOWING TEMPS IN THE LOW TO MID 30S WITH DEWPOINTS
IN THE UPPER 20S/LOW 30S. WINDS ARE LIGHT AND VARIABLE...AND SNOW
IS FALLING ACROSS MOST OF FORECAST AREA.

&&

.SHORT TERM /TONIGHT THROUGH FRIDAY/...

THE MAIN FOCUS OF THE SHORT TERM IS SNOW CHANCES ON FRIDAY/FRIDAY
NIGHT WITH A BROAD UPPER LEVEL LOW.

SKIES WILL BECOME CLEAR TONIGHT AS FLOW BECOMES MORE ZONAL. THIS
SHOULD ALLOW TEMPS TO FALL INTO THE LOWER 20S. AGAIN...WENT WITH A
MODEL BLEND. CLEAR SKIES AND DRY CONDITIONS WILL CONTINUE THROUGH
FRIDAY MORNING. HOWEVER...A BROAD UPPER LEVEL TROUGH WILL AFFECT
THE GREAT LAKES REGION ON FRIDAY...SPREADING SNOW INTO CENTRAL
INDIANA. THIS EVENT WILL BE QUICK JUST LIKE TODAY/S WITH THE BEST
LIFT MOVING THROUGH IN THE SATURDAY 00-06Z TIME FRAME.
HOWEVER...MOISTURE APPEARS LIMITED AT THIS TIME. SO...AMOUNTS
SHOULDN/T BE MUCH MORE THAN A HALF AN INCH WITH THE INITIAL BAND.
ADDITIONAL LAKE EFFECT SNOW SHOWERS ON SATURDAY COULD ADD AN
ADDITIONAL QUARTER TO HALF INCH TO THE TOTALS.

TEMPS WILL BE MILD ON THURSDAY WITH HIGHS STILL IN THE UPPER
30S/LOW 40S...AND LOWS IN THE 20S ON THURSDAY AND FRIDAY NIGHTS
DUE TO INCREASED CLOUD COVER. BUT...THEY WILL DECREASE SUBSTANTIALLY
BEHIND THIS DISTURBANCE AS DEEPER COLD AIR IS ABLE TO FILTER INTO
CENTRAL INDIANA.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...

COLDER PATTERN SETTING UP FOR THE WEEKEND AS SHARP UPPER TROUGH
DEVELOPS OVER THE EASTERN PART OF THE COUNTRY WITH DEEP POLAR VORTEX
PRESENT OVER QUEBEC. LINGERING SNOW SHOWERS AND FLURRIES LIKELY TO
STILL BE GOING OVER PORTIONS OF THE FORECAST AREA SATURDAY MORNING
AS THE TROUGH AXIS SHIFTS EAST. PRESENCE OF FAVORABLE N/NW LOW LEVEL
WIND FIELDS MAY PROVIDE FOR SOME LAKE ENHANCEMENT TO SNOW SHOWERS
INTO NORTHEAST PORTIONS OF THE FORECAST AREA SATURDAY MORNING.
EVENTUALLY DRIER AIR WILL BUILD IN SATURDAY AFTERNOON AND EVENING AS
WINDS BACK AND BROAD ARCTIC HIGH PRESSURE EXPANDS INTO THE OHIO
VALLEY. EXPECT TEMPS TO REMAIN IN THE 20S ON SATURDAY AS 850MB TEMPS
BOTTOM OUT AROUND -16C. LOWS IN THE TEENS ARE LIKELY SATURDAY NIGHT.

HIGH PRESSURE WILL MAINTAIN DRY WEATHER FOR CENTRAL INDIANA FOR
SUNDAY INTO EARLY NEXT WEEK WITH A SLOW RECOVERY IN TEMPERATURES AS
WARM ADVECTION COMMENCES IN THE LOWER LEVELS. HIGHS SHOULD WARM BACK
INTO THE MID AND UPPER 30S BY MONDAY. UNSETTLED WEATHER RETURNING
FOR THE END OF THE EXTENDED AS UPPER LEVEL RIDGE BUCKLES TO EAST AND
IS REPLACED BY AN UPPER LEVEL DISTURBANCE MONDAY NIGHT. ECMWF...OP
GFS AND GGEM IN RELATIVELY GOOD AGREEMENT WITH JUST SUBTLE TIMING
DIFFERENCES REGARDING TRACK OF THIS SYSTEM. WILL CARRY LOW CHANCE
POPS AS LIGHT PRECIPITATION IMPACTS THE FORECAST AREA MONDAY NIGHT
AND TUESDAY. PRECIP TYPE IS MURKIER AS SURFACE TEMPS MAY SNEAK BELOW
FREEZING WITH WARMER AIR ALOFT. CARRYING A RA/SN MIX MONDAY NIGHT
WITH A SHIFT TO MAINLY RAIN TUESDAY AS LOWER LEVEL THICKNESSES WARM
ENOUGH TO SUPPORT. MORE SUBSTANTIAL UPPER LEVEL SYSTEM WILL LIFT
INTO THE OHIO VALLEY ON WEDNESDAY/THURSDAY WITH A CHANCE FOR MORE
WIDESPREAD PRECIPITATION.

&&

.AVIATION /DISCUSSION FOR 081500Z TAF UPDATES/...

KEPT IFR CONDITIONS IN AT BMG THROUGH 17Z AND HUF THROUGH 16Z BASED
ON TRENDS AND THEN MVFR AFTER. MEANWHILE...ALTHOUGH IND AND LAF HAVE
BRIEFLY JUMPED TO VFR...UPSTREAM OBS SUGGEST A RETURN TO MVFR.

PREVIOUS DISCUSSION FOLLOWS...

IFR AND LOWER CONDITIONS THIS MORNING IN LIGHT SNOW...MVFR
CEILINGS THROUGH THIS EVENING.

UPPER LEVEL DISTURBANCE TRAVERSING THE REGION EARLY THIS MORNING
WITH LIGHT SNOW ACROSS CENTRAL INDIANA. VISIBILITIES HAVE BEEN
1-2SM IN HEAVIEST RETURNS WITH CEILINGS AT 400-1000FT AT THE FOUR
TERMINALS. HRRR AND RUC BOTH MOVE THE SNOW EAST OF THE TERMINALS
BY 15Z AND CURRENT RADAR TRENDS SUPPORT THIS TIMING. VISIBILITIES
WILL RECOVER TO MVFR PRIOR TO THE SNOW ENDING.

MODEL SOUNDINGS AND LOW LEVEL RH PROGS INDICATE MVFR STRATOCU WILL
PERSIST FOR THE REMAINDER OF THE DAY WITH LIGHT N/NW FLOW. CLOUDS
NOT LIKELY TO SCATTER UNTIL TRAILING SHORTWAVE PASSES TO THE EAST
THIS EVENING. SURFACE HIGH PRESSURE WITH DEEP SUBSIDENCE WILL
ENABLE CLEARING SKIES LATE. DRIER AIRMASS SHOULD PRECLUDE ANY FOG
FORMATION AT TERMINALS LATE TONIGHT AS WELL. WINDS WILL BACK TO
LIGHT W/NW OVERNIGHT.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SYNOPSIS...TDUD
NEAR TERM...TDUD
SHORT TERM...TDUD
LONG TERM....RYAN
AVIATION...RYAN/MK










AREA FORECAST DISCUSSION

NWS INDIANAPOLIS IN

 623 AM EST WED FEB 8 2012

.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...

A FEW DISTURBANCES WILL BRING SNOW TO CENTRAL INDIANA OVER THE
NEXT FEW DAYS. THE FIRST ONE WILL BE MOVING OUT OF THE AREA BY
LATE MORNING TODAY...BUT EXPECT LIGHT SNOW TO FALL UNTIL THEN
THIS MORNING. BRIEF RIDGING WILL THEN BUILD INTO THE AREA THROUGH
TOMORROW BEFORE ANOTHER DISTURBANCE BRINGS THE NEXT ROUND OF SNOW
ON FRIDAY AND FRIDAY NIGHT. ACCUMULATIONS WILL BE MINIMAL THOUGH
WITH BOTH EVENTS. FURTHER OUT...A QUICK DISTURBANCE WILL PASS OVER
CENTRAL INDIANA AT THE BEGINNING OF NEXT WEEK...BUT THIS LOOKS TO
BE MORE OF A RAIN/SNOW EVENT.

&&

.NEAR TERM /THIS MORNING AND TODAY/...

THE MAIN FOCUS OF THE NEAR TERM IS THE SNOW THIS MORNING.

CURRENT RADAR MOSAIC IS SHOWING WIDESPREAD PRECIP OVER MOST OF
CENTRAL INDIANA...WHICH IS FALLING IN THE FORM OF SNOW. CURRENT
ACTIVITY SHOULD BE THE MAIN SHOW FOR THIS PARTICULAR
DISTURBANCE...TAPERING OFF BY MID MORNING AS UPPER LEVEL LOW MOVES
EAST OF FORECAST AREA. SPS HAS BEEN ISSUED TO HIGHLIGHT IMPACTS
FOR MORNING RUSH HOUR. NO ADJUSTMENTS WERE MADE TO PREVIOUS
FORECAST AMOUNTS. STILL ANTICIPATE AMOUNTS LESS THAN INCH...WITH
LESSER AMOUNTS TO THE NORTH.

AS MENTIONED ABOVE...THIS WILL BE A QUICK EVENT WITH SNOW OUT OF
AREA BY LATE MORNING. NONETHELESS...SKIES WILL REMAIN MOSTLY
CLOUDY ALL DAY...WHICH WILL HINDER TEMPS. HIGHS WILL TOP OFF IN
THE MID TO UPPER 30S...FELT ALL BLEND WAS THE WAY TO GO SINCE THERE
WAS LITTLE DISCREPANCY IN MODELS.

LATEST OBS ARE SHOWING TEMPS IN THE LOW TO MID 30S WITH DEWPOINTS
IN THE UPPER 20S/LOW 30S. WINDS ARE LIGHT AND VARIABLE...AND SNOW
IS FALLING ACROSS MOST OF FORECAST AREA.

&&

.SHORT TERM /TONIGHT THROUGH FRIDAY/...

THE MAIN FOCUS OF THE SHORT TERM IS SNOW CHANCES ON FRIDAY/FRIDAY
NIGHT WITH A BROAD UPPER LEVEL LOW.

SKIES WILL BECOME CLEAR TONIGHT AS FLOW BECOMES MORE ZONAL. THIS
SHOULD ALLOW TEMPS TO FALL INTO THE LOWER 20S. AGAIN...WENT WITH A
MODEL BLEND. CLEAR SKIES AND DRY CONDITIONS WILL CONTINUE THROUGH
FRIDAY MORNING. HOWEVER...A BROAD UPPER LEVEL TROUGH WILL AFFECT
THE GREAT LAKES REGION ON FRIDAY...SPREADING SNOW INTO CENTRAL
INDIANA. THIS EVENT WILL BE QUICK JUST LIKE TODAY/S WITH THE BEST
LIFT MOVING THROUGH IN THE SATURDAY 00-06Z TIME FRAME.
HOWEVER...MOISTURE APPEARS LIMITED AT THIS TIME. SO...AMOUNTS
SHOULDN/T BE MUCH MORE THAN A HALF AN INCH WITH THE INITIAL BAND.
ADDITIONAL LAKE EFFECT SNOW SHOWERS ON SATURDAY COULD ADD AN
ADDITIONAL QUARTER TO HALF INCH TO THE TOTALS.

TEMPS WILL BE MILD ON THURSDAY WITH HIGHS STILL IN THE UPPER
30S/LOW 40S...AND LOWS IN THE 20S ON THURSDAY AND FRIDAY NIGHTS
DUE TO INCREASED CLOUD COVER. BUT...THEY WILL DECREASE SUBSTANTIALLY
BEHIND THIS DISTURBANCE AS DEEPER COLD AIR IS ABLE TO FILTER INTO
CENTRAL INDIANA.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...

COLDER PATTERN SETTING UP FOR THE WEEKEND AS SHARP UPPER TROUGH
DEVELOPS OVER THE EASTERN PART OF THE COUNTRY WITH DEEP POLAR VORTEX
PRESENT OVER QUEBEC. LINGERING SNOW SHOWERS AND FLURRIES LIKELY TO
STILL BE GOING OVER PORTIONS OF THE FORECAST AREA SATURDAY MORNING
AS THE TROUGH AXIS SHIFTS EAST. PRESENCE OF FAVORABLE N/NW LOW LEVEL
WIND FIELDS MAY PROVIDE FOR SOME LAKE ENHANCEMENT TO SNOW SHOWERS
INTO NORTHEAST PORTIONS OF THE FORECAST AREA SATURDAY MORNING.
EVENTUALLY DRIER AIR WILL BUILD IN SATURDAY AFTERNOON AND EVENING AS
WINDS BACK AND BROAD ARCTIC HIGH PRESSURE EXPANDS INTO THE OHIO
VALLEY. EXPECT TEMPS TO REMAIN IN THE 20S ON SATURDAY AS 850MB TEMPS
BOTTOM OUT AROUND -16C. LOWS IN THE TEENS ARE LIKELY SATURDAY NIGHT.

HIGH PRESSURE WILL MAINTAIN DRY WEATHER FOR CENTRAL INDIANA FOR
SUNDAY INTO EARLY NEXT WEEK WITH A SLOW RECOVERY IN TEMPERATURES AS
WARM ADVECTION COMMENCES IN THE LOWER LEVELS. HIGHS SHOULD WARM BACK
INTO THE MID AND UPPER 30S BY MONDAY. UNSETTLED WEATHER RETURNING
FOR THE END OF THE EXTENDED AS UPPER LEVEL RIDGE BUCKLES TO EAST AND
IS REPLACED BY AN UPPER LEVEL DISTURBANCE MONDAY NIGHT. ECMWF...OP
GFS AND GGEM IN RELATIVELY GOOD AGREEMENT WITH JUST SUBTLE TIMING
DIFFERENCES REGARDING TRACK OF THIS SYSTEM. WILL CARRY LOW CHANCE
POPS AS LIGHT PRECIPITATION IMPACTS THE FORECAST AREA MONDAY NIGHT
AND TUESDAY. PRECIP TYPE IS MURKIER AS SURFACE TEMPS MAY SNEAK BELOW
FREEZING WITH WARMER AIR ALOFT. CARRYING A RA/SN MIX MONDAY NIGHT
WITH A SHIFT TO MAINLY RAIN TUESDAY AS LOWER LEVEL THICKNESSES WARM
ENOUGH TO SUPPORT. MORE SUBSTANTIAL UPPER LEVEL SYSTEM WILL LIFT
INTO THE OHIO VALLEY ON WEDNESDAY/THURSDAY WITH A CHANCE FOR MORE
WIDESPREAD PRECIPITATION.

&&

.AVIATION /DISCUSSION FOR 081200Z TAF ISSUANCE/...

IFR AND LOWER CONDITIONS THIS MORNING IN LIGHT SNOW...MVFR
CEILINGS THROUGH THIS EVENING.

UPPER LEVEL DISTURBANCE TRAVERSING THE REGION EARLY THIS MORNING
WITH LIGHT SNOW ACROSS CENTRAL INDIANA. VISIBILITIES HAVE BEEN
1-2SM IN HEAVIEST RETURNS WITH CEILINGS AT 400-1000FT AT THE FOUR
TERMINALS. HRRR AND RUC BOTH MOVE THE SNOW EAST OF THE TERMINALS
BY 15Z AND CURRENT RADAR TRENDS SUPPORT THIS TIMING. VISIBILITIES
WILL RECOVER TO MVFR PRIOR TO THE SNOW ENDING.

MODEL SOUNDINGS AND LOW LEVEL RH PROGS INDICATE MVFR STRATOCU WILL
PERSIST FOR THE REMAINDER OF THE DAY WITH LIGHT N/NW FLOW. CLOUDS
NOT LIKELY TO SCATTER UNTIL TRAILING SHORTWAVE PASSES TO THE EAST
THIS EVENING. SURFACE HIGH PRESSURE WITH DEEP SUBSIDENCE WILL
ENABLE CLEARING SKIES LATE. DRIER AIRMASS SHOULD PRECLUDE ANY FOG
FORMATION AT TERMINALS LATE TONIGHT AS WELL. WINDS WILL BACK TO
LIGHT W/NW OVERNIGHT.

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SYNOPSIS...TDUD
NEAR TERM...TDUD
SHORT TERM...TDUD
LONG TERM....RYAN
AVIATION...RYAN







AREA FORECAST DISCUSSION...UPDATED

NWS TOPEKA KS

 540 AM CST WED FEB 8 2012

...UPDATE TO AVIATION...

.DISCUSSION...
09Z WATER VAPOR SHOWS SEVERAL SHORTWAVE WITH ONE MOVING EAST OF THE
FORECAST AREA...A SECOND CLOSED CIRCULATION OVER MT...AND A THIRD
WAVE OFF THE SOUTHERN CA COAST. MEANWHILE SFC OBS SHOW A COLD SFC
RIDGE OF HIGH PRESSURE NOSING INTO CENTRAL KS.

FOR TODAY THROUGH THURSDAY...THE FORECAST AREA SHOULD REMAIN UNDER
THE INFLUENCE OF NORTHWEST FLOW WITH THE WAVE OVER MT EVENTUALLY
SHEARING OUT AND MOVING TO THE EAST. THE SFC RIDGE BUILDING INTO
CENTRAL KS NOW WILL LIMIT ANY DEEP MOISTURE SO THE FORECAST REMAINS
DRY. THE MOST UNCERTAIN PART OF THE FORECAST IS WITH THE LOW CLOUDS.
THE NAM AND RUC ARE SUGGESTING THE STRATUS COULD HANG AROUND FOR A
GOOD CHUNK OF THE DAY. SO WITH MOSTLY CLOUDY TO OVERCAST SKIES AND
CONTINUED COLD AIR ADVECTION...TODAY`S HIGHS WILL NOT WARM UP MUCH.
WE SHOULD SEE SOME RETURN FLOW AND SUNSHINE FOR THURSDAY AS THE SFC
RIDGE MOVES EAST OF THE AREA. THIS SHOULD ALLOW FOR HIGHS TO WARM
INTO THE 40S.

THURSDAY NIGHT WILL SEE PERHAPS THE STRONGEST COLD FRONT IN TERMS OF
COLD AIR SO FAR THIS WINTER...AS AN ARCTIC AIRMASS BUILDS SOUTH
THROUGH THE PLAINS FOR FRIDAY AND SATURDAY. THE MODEL CONSENSUS IS
FOR STRONG COLD AIR ADVECTION TO OCCUR BEHIND THE FRONT THROUGH
SATURDAY. TO MAKE THINGS WORSE...THE COLD AIR WILL BE MOVING OVER
THE SNOWPACK ACROSS CENTRAL NEB. SO HAVE LOWERED TEMPS FOR FRIDAY
AND SATURDAY. TEMPS ON SATURDAY ARE NOT EXPECTED TO MAKE IT OUT OF
THE 20S. THE MODELS ARE SHOWING SOME MID LEVEL FRONTOGENESIS ON THE
WESTERN EDGE OF THE UPPER TROUGH FOR FRIDAY NIGHT AND SATURDAY. THIS
FRONTOGENESIS IS COINCIDENTAL WITH A NARROW AXIS OF MID LEVEL
MOISTURE. THE GFS AND ECMWF TEND TO KEEP THIS BAND JUST TO THE WEST
OF THE FORECAST AREA SO HAVE NOT INCLUDED ANY POPS AT THIS TIME.
HOWEVER WILL MENTION A SLIGHT CHANCE FOR SOME FLURRIES IN PARTS OF
NORTH CENTRAL KS ON SATURDAY.

THE MAKINGS OF A WINTER STORM APPEAR TO BE COMING TOGETHER FOR
SUNDAY NIGHT INTO MONDAY MORNING. THE MEDIUM RANGE MODELS ARE IN
REASONABLE AGREEMENT THAT A SHORTWAVE WILL MOVE FROM THE PACIFIC
INTO THE PLAINS AS THE HIGH AMPLITUDE UPPER RIDGE OVER THE WEST
COAST BREAKS DOWN. BUFKIT SOUNDINGS SHOW THE COLUMN SATURATING WITH
ANY WARM NOSE DUE TO WARM AIR ADVECTION SUNDAY NIGHT INCREASING TO
ONLY ABOUT +1C. THIS SHOULD NOT BE ENOUGH TO MELT ANY SNOW
COMPLETELY...AND THINK THE PREDOMINANT PRECIP TYPE SHOULD BE SNOW.
HOWEVER THE MID LEVEL WARM AIR ADVECTION SHOULD BRING PLENTY OF
MOISTURE TO GO ALONG WITH THE REASONABLE FORCING OF THE UPPER WAVE.
BECAUSE OF THIS HAVE INCREASED POPS FOR SUNDAY NIGHT AND MONDAY. QPF
FORECASTS FROM THE ECMWF AND GFS SUGGEST THAT THERE COULD BE A
COUPLE INCHES OF SNOW...WHICH IS IN LINE WITH THE MODEST FORCING
PROVIDED BY THE OPEN WAVE. IF PRECIP HANGS ON LONG ENOUGH INTO THE
DAY MONDAY...WARM AIR ADVECTION MAY BE STRONG ENOUGH TO CAUSE THE
PRECIP TO CHANGE OVER TO LIQUID BY MONDAY AFTERNOON. WHILE THINGS
ARE FAR FROM CERTAIN...THIS SYSTEM BARES WATCHING AS IT GETS CLOSER.

THE MODELS PROG AN ACTIVE WEATHER PATTERN FOR NEXT WEEK AS A SECOND
WAVE LIFTS OUT INTO THE PLAINS ON TUESDAY. THERE SEEMS TO BE SOME
AGREEMENT IN THE TIMING OF THIS SECOND WAVE. ALTHOUGH THERE IS SOME
DISAGREEMENT IN THE TRACK OF THIS WAVE. REGARDLESS BOTH MODELS...
ESPECIALLY THE ECMWF WITH ITS NORTHERN TRACK...BRING ENOUGH WARM AIR
NORTH INTO EASTERN KS THAT PRECIP SHOULD BE ALL RAIN. IF THE SYSTEM
IS ABLE TO BRING ENOUGH WARM AIR NORTH...THERE COULD EVEN BE ENOUGH
INSTABILITY FOR SOME CONVECTION. AGAIN THIS WILL NEED TO BE WATCHED
IN LATER RUNS. AT THIS POINT...THE FORECAST HAS MODERATING TEMPS
INTO TUESDAY WITH A CHANCE FOR SOME RAIN.

WOLTERS


&&

.AVIATION...

MVFR STRATUS WILL LINGER ACROSS ALL OF THE TERMINALS THROUGH
18Z AS SFC RIDGE SLIDES EASTWARD WITH DECREASING NORTH/NORTHWEST
WINDS. ALTHOUGH CEILINGS ARE EXPECTED TO GRADUALLY INCREASE TO
VFR BY 21Z-23Z TIME FRAME...FEEL THE COMBINATION OF RESIDUAL
MOISTURE LAYER NEAR AND JUST ABOVE 900MB WITHIN AREA OF WEAK
MIXING MAY BE ENOUGH TO ALLOW FOR STRATOCU DECK AROUND 3500 FT TO
LINGER THRU MUCH OF THE REMAINDER OF THE TAF FORECAST. AS A
RESULT...SFC WINDS WILL BE LIGHT AND VARIABLE.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$








AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

 1047 AM EST WED FEB 8 2012

.SYNOPSIS...
AN UPPER LEVEL SYSTEM WILL BRING WIDESPREAD SNOW SHOWERS TO THE
AREA TODAY. HIGH PRESSURE WILL BRING SEASONABLE TEMPERATURES AND
DRY CONDITIONS ON THURSDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UL WAVE IS SWINGING THROUGH THE UPPER OHIO VALLEY, AHEAD OF THE
MAIN TROUGH. THIS WAVE WILL MOVE THROUGH VERY QUICKLY...ENDING THE
SNOW FROM WEST TO EAST LATE THIS AFTERNOON.

CONFIDENT THAT THE HIGHEST AMOUNTS OF SNOW WILL BE 2 TO 4 INCHES
ACROSS THE RIDGE TOPS. ADVISORY CONTINUES FOR THE RIDGE COUNTIES
THROUGH THIS EVENING.

ELSEWHERE, A GENERAL 1 TO 2 WILL COVER MOST PLACES. ACCUMULATIONS
WILL BE LIMITED BY THE SPEED AT WHICH THIS SYSTEM WILL MOVE
THROUGH AND THAT MOST SFC TEMPS WILL RISE SLIGHTLY ABOVE FREEZING
TODAY, WITH THE EXCEPTION OF THE RIDGE TOPS.

TEMPERATURES ARE BLEND OF THE LATEST RUN OF THE HRRR AND 12Z NAM.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
SNOW SHOWERS ARE EXPECTED OVER THE SOUTHEAST RIDGES THIS EVENING,
WITH AN ADDITIONAL ACCUMULATION AROUND AN INCH POSSIBLE.

DRY HIGH PRESSURE WILL THEN BRING NEAR NORMAL TEMPERATURES INTO
FRIDAY.

FOR FRIDAY, MODELS CONTINUE TO HAVE TIMING ISSUES WITH ARCTIC
FRONT APPROACHING. HAVE GONE MIDDLE OF THE ROAD WITH HIGH CHANCE
TO LIKELY POPS LATE IN THE AFTERNOON. EXPECT A RAIN AND SNOW MIX
IN THE FAR SOUTH WITH SNOW ELSEWHERE. WILL PROBABLY AGAIN HAVE TO
DEAL WITH LIGHT ACCUMULATIONS. BUT WITH THIS SYSTEM, IT APPEARS
THE HIGHER ACCUMULATIONS WILL BE ACROSS THE NORTH.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
LATEST ECMWF AND GFS MODEL RUNS CONTINUE TO SHOW A DEEP UPPER TROUGH
PLUNGING ACROSS EASTERN CANADA DURING THE WEEKEND. 00Z ECMWF
INDICATES A SURFACE WAVE DEVELOPING ALONG THE BOUNDARY WHICH WOULD
TEND TO SLOW DOWN EASTWARD PROGRESS FRIDAY NIGHT...AND WOULD
LENGTHEN DURATION OF PRECIPITATION INTO SATURDAY. REGARDLESS OF
TIMING...VERY COLD CYCLONIC FLOW BEHIND THE SYSTEM SHOULD MAINTAIN
SCATTERED SNOW SHOWERS OVER THE REGION THROUGH SATURDAY.

STRONG SURFACE HIGH IS PROGGED TO BUILD SOUTHEASTWARD INTO THE MS
VALLEY BY SUNDAY AND THEN SLIDE EAST TO THE ATLANTIC COAST BY
TUESDAY. TEMPERATURES ARE FORECAST TO CHILL DOWN TO BETWEEN 5 AND 10
DEGREES BELOW NORMAL OVER THE WEEKEND...AND THEN MODERATE TO A FEW
DEGREES ABOVE NORMAL IN RETURN FLOW BY TUESDAY.

&&

.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
EXPECT GENERALLY IFR RESTRICTIONS TO CONTINUE WELL INTO THE
AFTERNOON AS SNOW ASSOCIATED WITH UPPER LEVEL SYSTEM MOVES ACROSS
THE TERMINALS. CONDITIONS SHOULD IMPROVE TO MVFR BY LATE AFTERNOON
AS STEADY SNOW TAPERS OFF TO SNOW SHOWERS BEFORE COMING TO AN END
IN ALL LOCATIONS THIS EVENING. CLEARING IS EXPECTED BY MIDNIGHT
THAT WILL FURTHER IMPROVE FLIGHT CONDITIONS TO VFR.

OUTLOOK...THURSDAY THROUGH SUNDAY...
BUILDING HIGH PRESSURE IN THE WAKE OF THE LOW PRESSURE SYSTEM
WILL PROVIDE VFR FOR THE END OF THE WORK WEEK. ANOTHER COLD FRONT
IS FORECAST TO SPAWN MORE SHSN FRIDAY NIGHT INTO SATURDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
     MDZ001.
OH...NONE.
PA...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
     PAZ074-076.
WV...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
     WVZ023-041.

&&

$$







AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

 1022 AM EST WED FEB 8 2012

.SYNOPSIS...
AN UPPER LEVEL SYSTEM WILL BRING WIDESPREAD SNOW SHOWERS TO THE
AREA TODAY. HIGH PRESSURE WILL BRING SEASONABLE TEMPERATURES AND
DRY CONDITIONS ON THURSDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UL WAVE IS SWINGING THROUGH THE UPPER OHIO VALLEY, AHEAD OF THE
MAIN TROUGH. THIS WAVE WILL MOVE THROUGH VERY QUICKLY...ENDING THE
SNOW FROM WEST TO EAST LATE THIS AFTERNOON.

CONFIDENT THAT THE HIGHEST AMOUNTS OF SNOW WILL BE 2 TO 4 INCHES
ACROSS THE RIDGE TOPS. ADVISORY CONTINUES FOR THE RIDGE COUNTIES
THROUGH THIS EVENING.

ELSEWHERE, A GENERAL 1 TO 2 WILL COVER MOST PLACES. ACCUMULATIONS
WILL BE LIMITED BY THE SPEED AT WHICH THIS SYSTEM WILL MOVE
THROUGH AND THAT MOST SFC TEMPS WILL RISE SLIGHTLY ABOVE FREEZING
TODAY, WITH THE EXCEPTION OF THE RIDGE TOPS.

TEMPERATURES ARE BLEND OF THE LATEST RUN OF THE HRRR AND 12Z NAM.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
SNOW SHOWERS ARE EXPECTED OVER THE SOUTHEAST RIDGES THIS EVENING,
WITH AN ADDITIONAL ACCUMULATION AROUND AN INCH POSSIBLE.

DRY HIGH PRESSURE WILL THEN BRING NEAR NORMAL TEMPERATURES INTO
FRIDAY.

FOR FRIDAY, MODELS CONTINUE TO HAVE TIMING ISSUES WITH ARCTIC
FRONT APPROACHING. HAVE GONE MIDDLE OF THE ROAD WITH HIGH CHANCE
TO LIKELY POPS LATE IN THE AFTERNOON. EXPECT A RAIN AND SNOW MIX
IN THE FAR SOUTH WITH SNOW ELSEWHERE. WILL PROBABLY AGAIN HAVE TO
DEAL WITH LIGHT ACCUMULATIONS. BUT WITH THIS SYSTEM, IT APPEARS
THE HIGHER ACCUMULATIONS WILL BE ACROSS THE NORTH.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
LATEST ECMWF AND GFS MODEL RUNS CONTINUE TO SHOW A DEEP UPPER TROUGH
PLUNGING ACROSS EASTERN CANADA DURING THE WEEKEND. 00Z ECMWF
INDICATES A SURFACE WAVE DEVELOPING ALONG THE BOUNDARY WHICH WOULD
TEND TO SLOW DOWN EASTWARD PROGRESS FRIDAY NIGHT...AND WOULD
LENGTHEN DURATION OF PRECIPITATION INTO SATURDAY. REGARDLESS OF
TIMING...VERY COLD CYCLONIC FLOW BEHIND THE SYSTEM SHOULD MAINTAIN
SCATTERED SNOW SHOWERS OVER THE REGION THROUGH SATURDAY.

STRONG SURFACE HIGH IS PROGGED TO BUILD SOUTHEASTWARD INTO THE MS
VALLEY BY SUNDAY AND THEN SLIDE EAST TO THE ATLANTIC COAST BY
TUESDAY. TEMPERATURES ARE FORECAST TO CHILL DOWN TO BETWEEN 5 AND 10
DEGREES BELOW NORMAL OVER THE WEEKEND...AND THEN MODERATE TO A FEW
DEGREES ABOVE NORMAL IN RETURN FLOW BY TUESDAY.

&&

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
CIGS WILL DROP AROUND SUNRISE TO MVFR AT MOST LOCATIONS IN
ADVANCE OF WEAK LOW PRESSURE SYSTEM. EXPECT THAT ALL LOCATIONS
EXCEPT FKL AND DUJ WILL DROP TO IFR AS WIDESPREAD SNOW MOVES IN
FROM SOUTHWEST TO NORTHEAST. FKL AND DUJ ARE EXPECTED TO REMAIN
MVFR THROUGH THE EVENT AS SNOW SHOULD BE LIGHTER COMPARED TO
LOCATIONS FARTHER TO THE SOUTH. THINK THAT SNOW COULD TAPER OFF
TO SNOW SHOWERS AROUND SUNSET BEFORE COMING TO AN END IN ALL
LOCATIONS THIS EVENING. CLEARING IS EXPECTED BY MIDNIGHT THAT WILL
BRING FLIGHT CONDITIONS BACK TO VFR.

OUTLOOK...THURSDAY THROUGH SATURDAY...
BUILDING HIGH PRES IN THE WAKE OF THE LOW PRESSURE SYSTEM WILL
PROVIDE VFR FOR THE END OF THE WORK WEEK...BUT ANOTHER COLD FRONT
IS FORECAST TO SPAWN MORE SHSN FRIDAY NIGHT INTO SATURDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
     MDZ001.
OH...NONE.
PA...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
     PAZ074-076.
WV...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
     WVZ023-041.

&&

$$







AREA FORECAST DISCUSSION

NWS GLASGOW MT

 350 AM MST WED FEB 8 2012

.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH FRIDAY...
THE SHORT TERM OF THE FORECAST STARTS OUT DIFFICULT WITH A SURFACE
HIGH EXTENDING INTO EXTREME NORTHEAST MONTANA...AND AN UPPER LOW
OVERHEAD. A MASS OF STRATUS CLOUDS RESIDES OVER MOST OF NORTHEAST
MONTANA AND SOUTHERN SASKATCHEWAN THIS MORNING. HRRR MODEL MOVES
THE MASS MORE NORTH INTO SASKATCHEWAN...HOWEVER DOES HOLD SOME
BACK OVER THE NORTHEASTERN ZONES THROUGH THE DAY. GOING TO TREND
TOWARDS AGAIN SOME CLEARING AS PER THE HRRR MODEL... BUT
CONFIDENCE ISN/T 100 PERCENT THAT THE STRATUS WON/T LIFT OUT UNTIL
THE LOW LEVEL EASTERLY FLOW SHIFTS WEST THIS EVENING.

TONIGHT... FOR NOW WILL GO WITH THE PARTLY CLOUDY SKY COVER...
HOWEVER LOOKING AT LAYERED RH HAS SOME CONCERN THAT THE MASS OF
STRATUS OVER SASKATCHEWAN WILL PUSH SOUTH AGAIN. KEEPING THAT IN
MIND DID A SPLIT ON TEMPERATURES...IF THE AREA STAYS CLEAR THE
FORECAST WILL BUST TOO WARM. IF THE STRATUS DOES COME IN THEN THE
FORECAST WILL SIDE TOO COLD.

THURSDAY...COLD AIR SPILLS IN FROM CENTRAL CANADA AND FORMS A
BOUNDARY WITH THE PACIFIC AIR MASS OVER CENTRAL MONTANA. THIS
SHOULD KEEP ANY SNOW FALL OUTSIDE OF THE FORECAST AREA WITH THE
EXCEPTION OF THE FAR SOUTHWESTERN ZONES. SKY COVER WILL BE HARD TO
HANDLE DURING THIS PERIOD. STRONG SURFACE HIGH AND DRY AIR WILL
KEEP THE NORTHEASTERN ZONES CLEAR...BUT AS THE PACIFIC MODIFIED
AIR MASS CLIMBS THE DEEP ARCTIC AIR A DECK OF CLOUDS IN VICINITY
OF THE FRONT.

THIS TREND WILL CONTINUE THURSDAY NIGHT INTO FRIDAY WITH
RE-ENFORCING SHOTS OF COLD AIR OVER THE EASTERN ZONES FROM THE
UPPER LOW OVER HUDSON BAY.                PROTON

.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...
THE PERIOD STARTS OUT ON THE COLD SIDE WITH A CANADIAN HIGH
PRESSURE STILL INFLUENCING THE AREA FRI NIGHT/SAT. THE AMPLIFIED
PATTERN BREAKS DOWN...WITH THE WESTERN RIDGE WEAKENING AND MOVING
E. THIS ALLOWS SHORTWAVES TO START MOVING INLAND ACROSS THE WESTERN
STATES BEGINNING SUNDAY.

QUITE A FEW MODEL DIFFERENCES WITH THESE SHORTAVES...TIMING...INTENSITY...
AND DIRECTION OF MOVEMENT. 00Z GFS QUITE DIFFERENT WITH A WEAKER
TUE SYSTEM...ENERGY ABSORBED BY A QUICKLY FOLLOWING WED SYSTEM.

THERE IS SIGNIFICANT WEAKENING OF THE UPPER FLOW OVER THE WESTERN
STATES...MAKING SPLITTING OF ENERGY LIKELY WITH THESE SYSTEMS. NONE OF
THESE SHORTWAVES ARE VERY STRONG EITHER. JUST ENOUGH MODEL
CONSENSUS TO EXPECT THE FIRST SHORTWAVE SUNDAY TO BE WEAKER THAN
THE 2ND SYSTEM TUE/TUE NIGHT. WILL MAINTAIN JUST A LITTLE HIGHER
POP FOR THESE. EXPECT PRECIP TYPE AS MAINLY LIGHT SNOW...ALTHOUGH
HIGHS LIKELY TO BE A LITTLE ABOVE FREEZING TUE. SIMONSEN

&&

.AVIATION...
PERSISTENT OVERCAST MVFR CEILINGS AT 2K FT AGL ARE ALREADY SHOWING
DEFINITE SIGNS OF BREAKING UP EARLY THIS MORNING. IT IS EXPECTED
THAT OUR 4 TAF SITES IN NE MT...OLF...GGW...SDY...GDV WILL BECOME
SCATTERED BY 12-14Z...THEN CLEAR. ALL REMAINING AREAS OF NE MT
SHOULD BE VFR BY 16Z. SIMONSEN

&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

WEATHER.GOV/GLASGOW






AREA FORECAST DISCUSSION

NWS OMAHA/VALLEY NE

 508 AM CST WED FEB 8 2012

.AVIATION...
12Z TAFS FOR KOFK...KLNK AND KOMA.

MVFR CIGS NEAR FL025 WILL CLEAR THE KOFK AREA EARLY...HOWEVER CIGS
BETWEEN FL025 AND FL035 WILL REMAIN OVER KLNK AND KOMA THROUGH THE
DAY. AS WINDS TURN TO THE SOUTHWEST LATE IN THE DAY...MVFR CIGS
BELOW FL020 SHOULD RETURN TO ALL TAF SITES...GENERALLY AROUND 00Z.
A GRADUAL LOWERING OF CIGS TO BELOW FL010 IS EXPECTED BY 06Z WITH
AREAS OF 5SM FOG.

DERGAN

&&

.PREV DISCUSSION... /ISSUED 316 AM CST WED FEB 8 2012/

DISCUSSION...

SFC HIGH PRESSURE CONTINUES TO MOVE SOUTH OVER THE FORECAST AREA
THIS MORNING WHILE LOW CLOUDS LINGER OVERHEAD. DIFFICULT TO GET A
GOOD HANDLE ON HOW QUICKLY/SLOWLY THE STRATUS DECK WILL ERODE. SOME
CLEARING HAS TAKEN PLACE OVER THE NORTHERN CWA AND ACROSS THE
MISSOURI RIVER VALLEY...HOWEVER THIS HAS BEEN A GENERALLY SLOW
PROCESS THIS MORNING. LATEST RUC AND HRRR MODEL RUNS SHOW SLOW SOUTHWARD
CLEARING SO WL KEEP MOSTLY CLOUDY GOING IN THE SOUTH WITH PARTLY
CLOUDY IN OUR NORTH FOR THE FIRST HALF OF THE DAY. IN THE UPPER
LEVELS...A PIECE OF ENERGY OVER EASTERN MONTANA WILL CONTINUE TO
MOVE SOUTHEAST TOWARD THE FORECAST AREA BY TONIGHT. FORCING
REMAINS VERY WEAK AND MOISTURE IS LIMITED SO NO MENTION OF
FLURRIES OR LIGHT SNOW WITH THE PASSAGE OF THIS WAVE.

WEAK WARM AIR ADVECTION SETS UP ON THURSDAY IN RETURN FLOW
REGIME...PROVIDING A BRIEF WARM UP INTO THE LOWER TO MID 30S. A
STRONG PUSH OF COLD AIR WILL SPREAD SOUTH ACROSS THE NRN PLAINS AND
INTO THE MIDWEST BY THURSDAY NIGHT IN ASSOCIATION WILL UPPER
TROF DIGGING ACROSS EASTERN CANADA. THE COLDER TEMPS WL CONTINUE
THROUGH THE WEEKEND WITH THE COLDEST OF THE DAYS ON SATURDAY. HIGHS
OVER THE SNOW COVER WILL LIKELY STRUGGLE TO WARM ABOVE THE UPPER
TEENS.

SFC HIGH PRESSURE BUILDS OVER THE CWA ONCE AGAIN ON SUNDAY WITH
STRONG WARM AIR ADVECTION RETURNING SUNDAY NIGHT. MEDIUM RANGE
MODELS IN GOOD AGREEMENT ON MOVING A SHORTWAVE TROF THRU THE FOUR
CORNERS REGION SUNDAY NIGHT AND INTO THE CENTRAL PLAINS BY MONDAY
MORNING. FORCING AHEAD OF THIS WAVE SHOULD ALLOW SNOW TO DEVELOP
SUNDAY NIGHT INTO MONDAY ACROSS MUCH OF THE SOUTHERN FORECAST
AREA.

YET ANOTHER WAVE IS PROGGED TO MOVE INTO THE CNTRL PLAINS FOR MID
WEEK. MODELS KEEP GETTING A BIT STRONGER WITH THIS SYSTEM AND
CONTINUE TO CLOSE IT OFF AS IT MOVES INTO THE CNTRL PLAINS.

KERN

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&

$$




AREA FORECAST DISCUSSION

NWS BISMARCK ND

 955 AM CST WED FEB 8 2012

.DISCUSSION...LOW-LEVEL STRATUS REMAINS ENTRENCHED ACROSS
NORTHWESTERN NORTH DAKOTA THIS MORNING. THE HRRR CONTINUES TO BE
THE SUPERIOR MODEL WITH RESPECT TO THE AREAL EXTENT AND EVOLUTION
OF LOW-LEVEL MOISTURE. AS A RESULT...WILL CONTINUE TO FORECAST
CLOSE TO ITS SOLUTION TODAY.

THE HRRR INDICATES THE STRATUS DECK WILL PIVOT ANTICYCLONICALLY
THROUGH THE REMAINDER OF THE MORNING AND BREAK UP THIS AFTERNOON
AS SYNOPTIC SUBSIDENCE OVERSPREADS THE REGION AND MIXES DRIER AIR
ALOFT TO THE SURFACE. THIS WILL CREATE A SLOWER WARM UP NORTH.
HAVE UPDATED THE FORECAST TO INDICATE THIS SLOWER TREND.
OTHERWISE...THE REMAINING WEATHER ELEMENTS ARE IN GOOD SHAPE. THE
UPDATED TEXT PRODUCTS WILL BE OUT SHORTLY.

&&

.AVIATION...MVFR-IFR CLOUDINESS IN THE NORTHWEST WITH CEILINGS
FALLING TO IFR AT WILLISTON DURING THE PAST HOUR. EXPECT THESE
CEILINGS TO CONTINUE INTO THE MID MORNING BEFORE DISSIPATING.
ELSEWHERE VFR CONDITIONS ARE EXPECTED. LIGHT WINDS THIS MORNING
WILL BECOME SOUTH TO SOUTHWEST THIS AFTERNOON AND TONIGHT.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

TM...UPDATE
NH...AVIATION





AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

 417 AM CST WED FEB 8 2012

.DISCUSSION...
A WEAK NORTHERN BOUNDARY SLIPPING ACROSS THE AREA EARLY THIS
MORNING...ONLY NOTICEABLE IN THE INCREASED PRESSURE FIELD AND
IN THE REINFORCING OF THE ANCHORED COOL AND DRY AIR MASS. A DAY
OF SCATTERED MID TO HIGH CLOUD COVER WITH THIS SLIGHTLY COOLER
NORTHERLY AIR MASS ONLY NOTICEABLE IN THE MAXIMUM TEMPERATURE
NUMBERS...A FEW DEGREES COOLER THAN YESTERDAY.

THE SYNOPTIC SCENARIO OF A MID TO LATE WEEK WEST COAST UPPER LOW
CUTTING OFF AND SETTLING IN OVER BAJA IS STILL ON TRACK...WITH
INCREASING PRECIPITATION CHANCES FROM LATE THURSDAY ON INTO THE
WEEKEND. CHANCE PROBABILITIES APPEAR TO BE ON THE RISE FRIDAY
INTO SATURDAY BECAUSE OF A FEW FACTORS. FIRST WOULD BE A SERIES OF
SHORTWAVE DISTURBANCES WITHIN THE SOUTHWEST-TO-NORTHEAST FLOW
RIDING UP THE COAST AND PROVIDING ENOUGH INSTABILITY...IN TANDEM
WITH DECENT ISENTROPIC UPLIFT...TO PRODUCE MAINLY LIGHT RAIN AND
ELEVATED THUNDER. ANOTHER POSITIVE WILL BE THE POSITIONING OF THE
SOUTHERN BRANCH OF THE POLAR JET STREAM...WITH COASTAL TEXAS
FALLING UNDER THE LF QUADRANT EARLY FRIDAY THEN TRANSITIONING TO
BEING UNDER THE RR QUAD LATTER IN THE DAY. THUS...WARM AIR
ADVECTION-TYPE LIGHT RAIN (LOW QPF) AS LOWER LEVEL DRY AIR (PER
ENTRENCHED LL (NORTH)EASTERLY FLOW) SHOULD COUNTERACT ANY
SIGNIFICANT ACCUMULATION/WIDESPREAD MODERATE RAIN COVERAGE.

SHALLOW UPPER LEVEL TROUGH AXIS WILL MOVE TO THE EAST OF TEXAS BY
SATURDAY AFTERNOON WITH ANOTHER WESTERN TROUGH EVOLVING OVER THE
ROCKIES SUNDAY INTO MONDAY. LEE SURFACE PRESSURES BEGIN TO LOWER
ACROSS WESTERN TEXAS EARLY MONDAY...ALLOWING MID-LOW WINDS TO TURN
AROUND TO ONSHORE AND BEGIN AN EARLY WEEK MOISTURE PUMP. INCREASING
HUMIDITIES AND RAIN CHANCES AS THE AREA FALLS JUST DOWNSTREAM OF A
DEVELOPING TEXAS PANHANDLE COLD FRONT. A PRIMARILY WEAK 5H TROUGH
PASSAGE MONDAY IS MODELED TO BE FOLLOWED BY A MUCH STRONGER STORM
SYSTEM TIMED TO AFFECT THE REGION A WEEK FROM NOW. THUS...MODEST
RAIN CHANCES FROM MONDAY`S WEAKER SYSTEM ARE FORECAST TO PICK UP
AGAIN WEDNESDAY. THE MAIN COLD FRONT IS TIMED TO PASS ACROSS TEXAS
WEDNESDAY BUT...IN THE DAYS LEADING UP TO THIS FROPA...EXPECT A COUPLE
OF WARM (LOWER 70 MAX TEMPS/LOWS IN THE 50S) AND MORE HUMID COUPLE
OF DAYS UNDER MAINLY OVERCAST SKIES AND HIGHER RAIN CHANCES. 31

&&

.MARINE...
PRES GRADIENT TIGHTENING OFFSHORE AND BELIEVE CURRENT FLAG CONFIGURATION
LOOKS GOOD (CAUTION BAYS & NEARSHORE, ADVISORY OFFSHORE) THROUGH
THIS AFTERNOON. WINDS WILL DIMINISH A BIT AND BECOME MORE NE LATE
IN THE DAY AND TONIGHT...BUT REMAIN AROUND 15 KT OFFSHORE FOR SEVERAL
DAYS. ANOTHER FRONT WILL DROP INTO THE PLAINS AND ERN U.S. THIS
WEEKEND WHICH WILL AGAIN TIGHTEN THE GRADIENT ALONG THE UPPER TX
COASTAL WATERS. CORRESPONDING WINDS & SEAS WILL INCREASE. TIDE
LEVELS WILL PROBABLY RUN 1-1.5 FEET ABOVE NORMAL THIS WEEKEND INTO
EARLY NEXT WEEK WITH A DECENT FETCH OF ENE WINDS IN PLACE. 47

&&

.AVIATION...
VFR.  47

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      61  41  64  46  63 /  10  10  20  30  30
HOUSTON (IAH)              64  42  65  45  65 /  10  10  20  20  30
GALVESTON (GLS)            62  50  62  51  64 /  10  10  20  20  30

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 3 PM CST THIS
     AFTERNOON FOR THE FOLLOWING ZONES: GALVESTON BAY...
     MATAGORDA BAY...WATERS FROM FREEPORT TO THE MATAGORDA SHIP
     CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT
     20 NM.

     SMALL CRAFT ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR THE
     FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
     CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
     FREEPORT 20 TO 60 NM.

&&

$$

DISCUSSION...31










AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 226 PM CST WED FEB 8 2012

.DISCUSSION...
356 AM CST

NEAR TERM CONCERNS THIS MORNING INCLUDE LIGHT SNOW ACROSS SOUTHERN
PARTS OF THE CWA...LINGERING LIGHT LAKE EFFECT SNOW THIS MORNING
OVER NORTHERN LAKE AND PORTER COUNTIES...AND CLOUD TRENDS ACROSS THE
AREA TODAY. LOOMING ON THE HORIZON IS A PUNCH OF ARCTIC AIR WHICH
ARRIVES FRIDAY...WITH THE FOCUS ON COLDER TEMPS AND THE POTENTIAL
FOR MORE SIGNIFICANT LAKE EFFECT SNOW ACROSS NORTHEAST IL AND
NORTHWEST INDIANA INTO SATURDAY.

LIGHT SNOW WAS OCCURRING EARLY THIS MORNING GENERALLY SOUTH OF A VYS
TO VPZ LINE...IN ASSOCIATION WITH AN UPPER DISTURBANCE MOVING ACROSS
DOWNSTATE IL INTO THE LOWER OHIO VALLEY. STRONGEST FORCING WITH THIS
SYSTEM WAS OCCURRING SOUTH OF THE CWA...WITH SFC OBS ACROSS OUR
SOUTHERN COUNTIES INDICATING  VISIBILITIES GENERALLY IN THE 3-7SM
RANGE AND SUGGESTING ONLY MINOR ACCUMULATIONS. LIGHT SNOW WILL
CONTINUE ACROSS THE SOUTH THIS MORNING...SHIFTING MAINLY EAST OF
INTERSTATE 57 BY 12Z. LITTLE ADDITIONAL ACCUMULATION IS EXPECTED.

FARTHER NORTH...A WEAK BAND OF LAKE EFFECT SNOW WAS IMPINGING ON
NORTHWEST LAKE COUNTY AND FAR SOUTHEAST COOK COUNTY. BAND WAS
HEAVIER FOR A TIME LATE LAST EVENING...WITH SOME ACCUMULATION NOTED
ON WEB CAMS ALONG THE INTERSTATES. RADAR RETURNS HAVE WEAKENED
CONSIDERABLY...AND HIGH RES MODEL GUIDANCE SEEMS TO HAVE CAPTURED
THIS TREND NICELY. BOTH RUC AND NAM DO INDICATE THAT SLIGHT COOLING
AROUND 900 HPA MAY SLIGHTLY IMPROVE THE LOW-LEVEL THERMODYNAMIC
PROFILE AROUND 12Z THIS MORNING...BEFORE EQUILIBRIUM HEIGHTS LOWER
BELOW 4000 FT AND LOW LEVEL WINDS BACK AROUND TO THE NORTHWEST BY
MIDDAY. THEREFORE EXPECT LIGHT SNOW SHOWERS TO CONTINUE THROUGH MID
MORNING...SHIFTING EAST AND WEAKENING WITH TIME IN THE 15-18Z
PERIOD. CURRENT WEB CAM VIEWS FROM 80/94 NEAR HAMMOND INDICATE
CURRENT ACTIVITY HAVING LITTLE/NO IMPACT ON VISIBILITY AT 330
AM...AND HAVE ONLY INCLUDED AN ADDITIONAL TENTH OF AN INCH OF
SNOWFALL THIS MORNING MAINLY ACROSS NORTHERN LAKE COUNTY...THOUGH
WILL MONITOR FOR ANY SIGNS OF BETTER DEVELOPMENT PRIOR TO SUNRISE.

GOES 11-3.9 MICRON IMAGERY SHOWS CLEARING OF LOW CLOUDS WAS
OCCURRING ACROSS FAR NORTHWEST IL EARLY THIS MORNING...THOUGH LOW
CLOUDS STRETCHED BACK ACROSS A LARGE PORTION OF CENTRAL IA. A SHORT
WAVE TROUGH DIGGING SOUTHEAST ACROSS THE HAWKEYE STATE MAY SLOW
CLEARING FOR A TIME THIS MORNING...BEFORE THE MID-LEVEL VORT AND
TROUGH AXIS PASS INTO CENTRAL IL EARLY THIS AFTERNOON. DRIER LOW
LEVEL AIR JUST UPSTREAM WILL ADVECT INTO THE AREA FROM THE NORTHWEST
HOWEVER WHICH SHOULD ALLOW CLEARING FROM THE NORTH/NORTHWEST THROUGH
THE DAY...WITH SOUTHEASTERN COUNTIES CLEARING LAST. MODEL
TIME/HEIGHT SECTIONS THEN APPEAR QUITE DRY TONIGHT THROUGH THURSDAY.
TEMPERATURE GUIDANCE IN FAIRLY CLOSE AGREEMENT DURING THIS PERIOD
AND GENERALLY USED A BLEND LEANING A LITTLE TOWARD THE COOLER
NUMBERS TODAY...AND TOWARD THE WARMER END OF THE RANGE WITH MORE SUN
AND WEAK WARM ADVECTION DEVELOPING THURSDAY.

GUIDANCE CONTINUES TO DEPICT SIGNIFICANT AMPLIFICATION OF THE UPPER
FLOW FOR THE END OF THE WEEK...WITH LARGE TROUGH DEVELOPING OVER
MUCH OF EASTERN NORTH AMERICA AND AT LEAST A TEMPORARY PUSH OF
ARCTIC AIR. MAIN AREA OF LOW PRESSURE IS PROGGED TO DEVELOP JUST
NORTH OF LAKE SUPERIOR ON THURSDAY AHEAD OF MID-LEVEL SHORT WAVE...
WITH UPPER WAVE AND SURFACE COLD FRONT PUSHING ACROSS THE FORECAST
AREA EARLY FRIDAY. MODELS INDICATE CONSIDERABLE DRY AIR IN THE
850-650 HPA LAYER PRECLUDING MUCH OF A PRECIPITATION THREAT...THOUGH
FAIRLY STRONG ISENTROPIC ASCENT IN THE WARM ADVECTION AHEAD OF THE
TROUGH MAY RESULT IN ENOUGH SATURATION IN THE 280-285 K LAYER TO
PRODUCE SOME FLURRIES FRIDAY MORNING. STRONG COLD ADVECTION ON
BLUSTERY NORTHERLY WINDS FRIDAY WILL LIKELY PRODUCE FALLING DAYTIME
TEMPS INTO THE 20S...WITH 850 HPA TEMPS FROM GFS/ECMWF DEPICTING -17
TO -19 C OVER THE AREA BY 12Z SATURDAY.

BESIDES THE COLD...THE REAL FORECAST CONCERN IN THE FRIDAY-SATURDAY
PERIOD IS THE POTENTIAL FOR LAKE EFFECT SNOW INTO NORTHEAST IL AND
NORTHWEST INDIANA. LAKE SURFACE TO 850 HPA DELTAS INCREASE INTO THE
LOW 20S LATE FRIDAY THROUGH SATURDAY MORNING...DURING A PERIOD IN
WHICH THE LOW LEVEL WINDS WILL BE NORTH-NORTHEAST DOWN THE FULL
FETCH OF THE LAKE. FORECAST SOUNDINGS INDICATE EQUILIBRIUM LEVELS
RISING TO NEAR 9000 FT BY 12Z SATURDAY...WITH LAKE INDUCED CAPES OF
400-500 J/KG. THIS WOULD SUGGEST THE POTENTIAL FOR SOME SIGNIFICANT
ACCUMULATING LAKE EFFECT FROM FRIDAY AFTERNOON THROUGH SATURDAY
MORNING. ONLY LIMITING FACTOR WOULD BE THE VERY DRY ARCTIC AIR
SPREADING ACROSS THE WESTERN LAKES...THOUGH THE LONG FETCH WILL
LIKELY PROVIDE ENOUGH MOISTURE FLUX TO MAKE UP FOR THE DRYNESS OF
THE AIRMASS. WILL BE INTERESTING TO SEE SOME OF THE HIGH RESOLUTION
GUIDANCE AS THE FRIDAY-SATURDAY PERIOD APPROACHES. FOR NOW HAVE
INCREASED POPS FOR THE LAKESIDE COUNTIES...AND WILL HIGHLIGHT
POTENTIAL FOR ACCUMULATING LAKE SNOWS IN THE HAZARDOUS WEATHER
OUTLOOK.

LONGER RANGE GUIDANCE IN A LITTLE BETTER AGREEMENT IN SHIFTING UPPER
TROUGH OFF TO THE EAST SUNDAY...AND BUILDING SURFACE HIGH PRESSURE
RIDGE IN FROM THE WEST SUNDAY NIGHT. WARM ADVECTION WORKS TO PUSH
THE ARCTIC AIR AWAY MONDAY AS LOW LEVEL WINDS SHIFT TO THE SOUTH.
BOTH OPERATIONAL ECMWF AND GFS INDICATE A SHORT WAVE LIFTING
NORTHEAST ACROSS THE REGION LATE MONDAY SUGGESTING POTENTIAL FOR
SOME LIGHT SNOW MONDAY NIGHT INTO TUESDAY...WITH TEMPS CLIMBING A
BIT BACK ABOVE NORMAL.

RATZER

&&

.AVIATION...

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

* NONE.

KJB

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

SKIES ARE IN THE PROCESS OF CLEARING ACROSS NORTHEASTERN ILLINOIS
AND NORTHWESTERN INDIANA LATE THIS MORNING. ONCE SKIES DO
CLEAR...THEY SHOULD REMAIN SO FOR THE REMAINED OF THE PERIOD.
SURFACE HIGH PRESSURE WILL DOMINATE ACROSS THE MID MISSISSIPPI
VALLEY THROUGH MUCH OF THURSDAY. THIS WILL CONTINUE TO SET UP WEST
TO SOUTHWESTERLY SURFACE FLOW ACROSS THE AREA. NO WEATHER CONCERNS
ARE EXPECTED IN THE NEXT 36 HOURS.

KJB

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

* HIGH CONFIDENCE ON ALL FORECAST ELEMENTS.

KJB

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

THURSDAY NIGHT...VFR.
FRIDAY/SATURDAY...CHC LAKE EFFECT SNOW WITH MVFR/IFR POSSIBLE.
SUNDAY/MONDAY...VFR.
TUESDAY...SLT CHC RAIN/SNOW.
BMD

&&

.MARINE...
225 PM CST

THE CONCERNS WITH THE MARINE FORECAST MAINLY CENTER ON THE POTENTIAL
GALE FORCE WINDS ON FRIDAY WITH THE PASSAGE OF AN ARCTIC FRONT. IN
THE MEANTIME...A RIDGE OF HIGH PRESSURE OVER THE SOUTHERN LAKES WILL
GRADUALLY SLIDE SOUTH THROUGH TONIGHT AND INTO THURSDAY. WINDS AND
WAVES SHOULD STAY FAIRLY STEADY IN THAT TIME. LOW PRESSURE WILL MOVE
SOUTHEAST ACROSS ONTARIO ON THURSDAY NIGHT AND SWING A STRONG COLD
FRONT SOUTH ACROSS LAKE MICHIGAN ON FRIDAY. IMMEDIATELY AFTER THIS
PASSAGE...A PERIOD OF NORTHERLY GALE FORCE GUSTS LOOK LIKELY AT THIS
TIME...INCLUDING POTENTIALLY ALONG THE INDIANA NEAR SHORE. SOME
SCATTERED FREEZING SPRAY APPEARS POSSIBLE OVER THE LAKE GIVEN THE
DEGREE OF COLD AIR FORECAST...PRIMARILY OVER THE NORTHERN PORTION.
IN ADDITION...SOME PROLONGED LAKE EFFECT SNOW IS LIKELY ACROSS THE
FAR SOUTHERN PART OF THE LAKE. WINDS WILL BE VERY SLOW TO DIMINISH
AND WAVES JUST AS STUBBORN TO SUBSIDE THROUGH FRIDAY NIGHT AND
SATURDAY.

MTF

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...6 AM FRIDAY TO
     MIDNIGHT SATURDAY.

&&

$$







AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 156 PM CST WED FEB 8 2012

.DISCUSSION...
356 AM CST

NEAR TERM CONCERNS THIS MORNING INCLUDE LIGHT SNOW ACROSS SOUTHERN
PARTS OF THE CWA...LINGERING LIGHT LAKE EFFECT SNOW THIS MORNING
OVER NORTHERN LAKE AND PORTER COUNTIES...AND CLOUD TRENDS ACROSS THE
AREA TODAY. LOOMING ON THE HORIZON IS A PUNCH OF ARCTIC AIR WHICH
ARRIVES FRIDAY...WITH THE FOCUS ON COLDER TEMPS AND THE POTENTIAL
FOR MORE SIGNIFICANT LAKE EFFECT SNOW ACROSS NORTHEAST IL AND
NORTHWEST INDIANA INTO SATURDAY.

LIGHT SNOW WAS OCCURRING EARLY THIS MORNING GENERALLY SOUTH OF A VYS
TO VPZ LINE...IN ASSOCIATION WITH AN UPPER DISTURBANCE MOVING ACROSS
DOWNSTATE IL INTO THE LOWER OHIO VALLEY. STRONGEST FORCING WITH THIS
SYSTEM WAS OCCURRING SOUTH OF THE CWA...WITH SFC OBS ACROSS OUR
SOUTHERN COUNTIES INDICATING  VISIBILITIES GENERALLY IN THE 3-7SM
RANGE AND SUGGESTING ONLY MINOR ACCUMULATIONS. LIGHT SNOW WILL
CONTINUE ACROSS THE SOUTH THIS MORNING...SHIFTING MAINLY EAST OF
INTERSTATE 57 BY 12Z. LITTLE ADDITIONAL ACCUMULATION IS EXPECTED.

FARTHER NORTH...A WEAK BAND OF LAKE EFFECT SNOW WAS IMPINGING ON
NORTHWEST LAKE COUNTY AND FAR SOUTHEAST COOK COUNTY. BAND WAS
HEAVIER FOR A TIME LATE LAST EVENING...WITH SOME ACCUMULATION NOTED
ON WEB CAMS ALONG THE INTERSTATES. RADAR RETURNS HAVE WEAKENED
CONSIDERABLY...AND HIGH RES MODEL GUIDANCE SEEMS TO HAVE CAPTURED
THIS TREND NICELY. BOTH RUC AND NAM DO INDICATE THAT SLIGHT COOLING
AROUND 900 HPA MAY SLIGHTLY IMPROVE THE LOW-LEVEL THERMODYNAMIC
PROFILE AROUND 12Z THIS MORNING...BEFORE EQUILIBRIUM HEIGHTS LOWER
BELOW 4000 FT AND LOW LEVEL WINDS BACK AROUND TO THE NORTHWEST BY
MIDDAY. THEREFORE EXPECT LIGHT SNOW SHOWERS TO CONTINUE THROUGH MID
MORNING...SHIFTING EAST AND WEAKENING WITH TIME IN THE 15-18Z
PERIOD. CURRENT WEB CAM VIEWS FROM 80/94 NEAR HAMMOND INDICATE
CURRENT ACTIVITY HAVING LITTLE/NO IMPACT ON VISIBILITY AT 330
AM...AND HAVE ONLY INCLUDED AN ADDITIONAL TENTH OF AN INCH OF
SNOWFALL THIS MORNING MAINLY ACROSS NORTHERN LAKE COUNTY...THOUGH
WILL MONITOR FOR ANY SIGNS OF BETTER DEVELOPMENT PRIOR TO SUNRISE.

GOES 11-3.9 MICRON IMAGERY SHOWS CLEARING OF LOW CLOUDS WAS
OCCURRING ACROSS FAR NORTHWEST IL EARLY THIS MORNING...THOUGH LOW
CLOUDS STRETCHED BACK ACROSS A LARGE PORTION OF CENTRAL IA. A SHORT
WAVE TROUGH DIGGING SOUTHEAST ACROSS THE HAWKEYE STATE MAY SLOW
CLEARING FOR A TIME THIS MORNING...BEFORE THE MID-LEVEL VORT AND
TROUGH AXIS PASS INTO CENTRAL IL EARLY THIS AFTERNOON. DRIER LOW
LEVEL AIR JUST UPSTREAM WILL ADVECT INTO THE AREA FROM THE NORTHWEST
HOWEVER WHICH SHOULD ALLOW CLEARING FROM THE NORTH/NORTHWEST THROUGH
THE DAY...WITH SOUTHEASTERN COUNTIES CLEARING LAST. MODEL
TIME/HEIGHT SECTIONS THEN APPEAR QUITE DRY TONIGHT THROUGH THURSDAY.
TEMPERATURE GUIDANCE IN FAIRLY CLOSE AGREEMENT DURING THIS PERIOD
AND GENERALLY USED A BLEND LEANING A LITTLE TOWARD THE COOLER
NUMBERS TODAY...AND TOWARD THE WARMER END OF THE RANGE WITH MORE SUN
AND WEAK WARM ADVECTION DEVELOPING THURSDAY.

GUIDANCE CONTINUES TO DEPICT SIGNIFICANT AMPLIFICATION OF THE UPPER
FLOW FOR THE END OF THE WEEK...WITH LARGE TROUGH DEVELOPING OVER
MUCH OF EASTERN NORTH AMERICA AND AT LEAST A TEMPORARY PUSH OF
ARCTIC AIR. MAIN AREA OF LOW PRESSURE IS PROGGED TO DEVELOP JUST
NORTH OF LAKE SUPERIOR ON THURSDAY AHEAD OF MID-LEVEL SHORT WAVE...
WITH UPPER WAVE AND SURFACE COLD FRONT PUSHING ACROSS THE FORECAST
AREA EARLY FRIDAY. MODELS INDICATE CONSIDERABLE DRY AIR IN THE
850-650 HPA LAYER PRECLUDING MUCH OF A PRECIPITATION THREAT...THOUGH
FAIRLY STRONG ISENTROPIC ASCENT IN THE WARM ADVECTION AHEAD OF THE
TROUGH MAY RESULT IN ENOUGH SATURATION IN THE 280-285 K LAYER TO
PRODUCE SOME FLURRIES FRIDAY MORNING. STRONG COLD ADVECTION ON
BLUSTERY NORTHERLY WINDS FRIDAY WILL LIKELY PRODUCE FALLING DAYTIME
TEMPS INTO THE 20S...WITH 850 HPA TEMPS FROM GFS/ECMWF DEPICTING -17
TO -19 C OVER THE AREA BY 12Z SATURDAY.

BESIDES THE COLD...THE REAL FORECAST CONCERN IN THE FRIDAY-SATURDAY
PERIOD IS THE POTENTIAL FOR LAKE EFFECT SNOW INTO NORTHEAST IL AND
NORTHWEST INDIANA. LAKE SURFACE TO 850 HPA DELTAS INCREASE INTO THE
LOW 20S LATE FRIDAY THROUGH SATURDAY MORNING...DURING A PERIOD IN
WHICH THE LOW LEVEL WINDS WILL BE NORTH-NORTHEAST DOWN THE FULL
FETCH OF THE LAKE. FORECAST SOUNDINGS INDICATE EQUILIBRIUM LEVELS
RISING TO NEAR 9000 FT BY 12Z SATURDAY...WITH LAKE INDUCED CAPES OF
400-500 J/KG. THIS WOULD SUGGEST THE POTENTIAL FOR SOME SIGNIFICANT
ACCUMULATING LAKE EFFECT FROM FRIDAY AFTERNOON THROUGH SATURDAY
MORNING. ONLY LIMITING FACTOR WOULD BE THE VERY DRY ARCTIC AIR
SPREADING ACROSS THE WESTERN LAKES...THOUGH THE LONG FETCH WILL
LIKELY PROVIDE ENOUGH MOISTURE FLUX TO MAKE UP FOR THE DRYNESS OF
THE AIRMASS. WILL BE INTERESTING TO SEE SOME OF THE HIGH RESOLUTION
GUIDANCE AS THE FRIDAY-SATURDAY PERIOD APPROACHES. FOR NOW HAVE
INCREASED POPS FOR THE LAKESIDE COUNTIES...AND WILL HIGHLIGHT
POTENTIAL FOR ACCUMULATING LAKE SNOWS IN THE HAZARDOUS WEATHER
OUTLOOK.

LONGER RANGE GUIDANCE IN A LITTLE BETTER AGREEMENT IN SHIFTING UPPER
TROUGH OFF TO THE EAST SUNDAY...AND BUILDING SURFACE HIGH PRESSURE
RIDGE IN FROM THE WEST SUNDAY NIGHT. WARM ADVECTION WORKS TO PUSH
THE ARCTIC AIR AWAY MONDAY AS LOW LEVEL WINDS SHIFT TO THE SOUTH.
BOTH OPERATIONAL ECMWF AND GFS INDICATE A SHORT WAVE LIFTING
NORTHEAST ACROSS THE REGION LATE MONDAY SUGGESTING POTENTIAL FOR
SOME LIGHT SNOW MONDAY NIGHT INTO TUESDAY...WITH TEMPS CLIMBING A
BIT BACK ABOVE NORMAL.

RATZER

&&

.AVIATION...

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

* NONE.

KJB

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

SKIES ARE IN THE PROCESS OF CLEARING ACROSS NORTHEASTERN ILLINOIS
AND NORTHWESTERN INDIANA LATE THIS MORNING. ONCE SKIES DO
CLEAR...THEY SHOULD REMAIN SO FOR THE REMAINED OF THE PERIOD.
SURFACE HIGH PRESSURE WILL DOMINATE ACROSS THE MID MISSISSIPPI
VALLEY THROUGH MUCH OF THURSDAY. THIS WILL CONTINUE TO SET UP WEST
TO SOUTHWESTERLY SURFACE FLOW ACROSS THE AREA. NO WEATHER CONCERNS
ARE EXPECTED IN THE NEXT 36 HOURS.

KJB

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

* HIGH CONFIDENCE ON ALL FORECAST ELEMENTS.

KJB

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

THURSDAY NIGHT...VFR.
FRIDAY/SATURDAY...CHC LAKE EFFECT SNOW WITH MVFR/IFR POSSIBLE.
SUNDAY/MONDAY...VFR.
TUESDAY...SLT CHC RAIN/SNOW.
BMD

&&

.MARINE...
315 AM CST

FOLLOWING THE PASSAGE OF A COLD FRONT AND WITH HIGH PRESSURE
BUILDING ACROSS THE NORTHERN PLAINS AND UPPER MISSISSIPPI
VALLEY...WINDS WILL GRADUALLY DIMINISH. AS THE HIGH PRESSURE SAGS
TO THE SOUTHEAST WEDNESDAY AND THURSDAY...WINDS WILL BECOME
WESTERLY TO 25KT AND EVENTUALLY SOUTHWESTERLY...AS ANOTHER ARCTIC
COLD FRONT APPROACHES. THIS FRONT WILL PUSH ACROSS THE LAKE
THURSDAY NIGHT. A STRONG PUSH OF COLD AIR MAY BRING WINDS UP TO
GALE FORCE OVER THE FAR NORTHERN PORTIONS OF THE LAKE LATE
THURSDAY INTO THURSDAY NIGHT.

KREIN

&&

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

$$





AREA FORECAST DISCUSSION

NWS LINCOLN IL

 1156 AM CST WED FEB 8 2012

.DISCUSSION...
ISSUED 915 AM CST WED FEB 8 2012

WILL BE UPDATING THE FORECAST SHORTLY TO ADJUST THE MORNING PERIOD
WITH LIGHT SNOW AND FLURRIES OVER EASTERN IL WITH LITTLE OR NO
ADDITIONAL ACCUMULATIONS EXPECTED. ALSO ADJUSTING THE SKY COVER
TODAY WITH SLOWING CLEARING DOWN A BIT FROM THE NORTH. HIGHS 32 TO
38F LOOK ON TRACK WITH MILDEST READINGS IN SE IL.

FAIRLY STRONG UPPER LEVEL TROF OVER THE MIDWEST INCLUDING IL HAD A
LARGE AREA OF LOW CLOUDS OVER MUCH OF MO/IL/IN AND SE IA. THERE
WAS A CLEAR SLOT OVER NW IL AS FAR SOUTH AS PEORIA. AREA OF VERY
LIGHT SNOW AND FLURRIES WAS FROM BLOOMINGTON/NORMAL NE AND
DRIFTING SE TOWARD CHAMPAIGN/URBANA. TEMPS RANGED FROM THE UPPER
20S OVER CENTRAL IL NW OF I-70...TO THE MID 30S IN SE IL FROM
ROBINSON TO FLORA SE. NW WINDS 7 TO 13 MPH WAS USHERING IN DRIER
AIR WITH DEWPOINTS RANGING FROM THE UPPER TEENS AND LOWER 20S NW
OF I-55 TO THE UPPER 20S TO NEAR 30F FROM DANVILLE TO TAYLORVILLE
SE.

HI-RESOLUTION 12Z HRRR MODEL ACTUALLY SHOWS POCKETS OF VERY LIGHT
SNOW SHOWERS AND FLURRIES LINGERING OVER CENTRAL IL THROUGH THE
DAY. 12Z NAM...SREF AND RUC MODELS SHOW BRUN OF THE LIGHT SNOW
EAST OF IL TODAY WITH LIGHT POCKETS OF QPF OVER EAST CENTRAL IL
THIS MORNING WHICH BETTER SUPPORTS RADAR TENDS AND LEANED IN THIS
DIRECTION. DID SLOW CLEARING OF THE LOW CLOUDS FROM THE NORTH TODAY
WITH LOW CLOUDS LINGERING MUCH OF TODAY OVER SE IL. 1035 MB HIGH
PRESSURE OVER EASTERN NEBRASKA WILL SETTLE INTO THE MID MS VALLEY
BY THU MORNING HELPING CLEAR THE REST OF THE LOW CLOUDS TONIGHT
AND BRINGING SEASONABLY COLD TEMPS TODAY AND TONIGHT. NW WINDS 7
TO 13 MPH TODAY TO BECOME LIGHT WEST DURING TONIGHT AS HIGH
PRESSURE SETTLES IN.

HUETTL

&&

.AVIATION...
ISSUED 1155 AM CST WED FEB 8 2012

VFR CEILINGS OF 3-5K FT WILL OCCUR THIS AFTERNOON AND THEN
SCATTERED OUT DURING THIS EVENING FROM NW TO SE. THERE WILL STILL
BE SOME MFVR CEILINGS FROM 1.2-3K FT FROM BMI AND DEC EAST TO CMI
UNTIL MID AFTERNOON WITH FLURRIES STILL NEAR CMI NEXT HOUR OR SO.
MVFR VISIBILITIES POSSIBLE LATE TONIGHT/EARLY THU MORNING WITH
LIGHT FOG WITH CLEAR SKIES AND LIGHT WINDS. MVFR CEILINGS TO
SPREAD BACK EAST INTO THE MS VALLEY LATE THU MORNING FROM 15Z-18Z
AND LIKELY TO SPREAD EAST ACROSS PIA AND SPI AND TO HIGHWAY 51 BY
BMI AND DEC BETWEEN 18Z-21Z THU JUST AFTER THE 24 HOUR TAF PERIOD.
NW WINDS AROUND 10 KTS THIS AFTERNOON TO DIMINISH LIGHT THIS
EVENING AND BE W/SW 7-11 KTS FROM MID THU MORNING ON.

FAIRLY STRONG UPPER LEVEL TROF OVER THE GREAT LAKES REGION AND
OHIO VALLEY INCLUDING IL WILL KEEP A FAIR AMOUNT OF LOW CLOUDS
AROUND THIS AFTERNOON WHICH EXTEND UPSTREAM INTO SE IOWA. EVEN
THE DRY SLOT AROUND PIA IS FILLING BACK IN WITH BROKEN CUMULUS
CLOUDS AT MIDDAY. USED THE 925-850 MB RH FIELD FROM THE HI-RES
MODELS TO TIME CLEARING/SCATTERING OUT OF LOW CLOUDS FROM NW TO SE
DURING THIS EVENING. 1035 MB HIGH PRESSURE OVER THE CENTRAL PLAINS
OVER EASTERN NEBRASKA/KS WILL SETTLE INTO THE MID MS VALLEY THU
MORNING. A SHORT WAVE NEAR THE MT/SD BORDER WILL RACE ESE TOWARD
THE IL/MO/IA BORDER LATE THU MORNING SPREADING LOW CLOUDS BACK
EAST TOWARD THE MS VALLEY AND COULD APPROACH PIA AND SPI BY
18Z/NOON THU.

HUETTL

&&

.PREV DISCUSSION...
ISSUED 250 AM CST WED FEB 8 2012

THE SHORTWAVE MOVING ACROSS THE CENTRAL U.S. WAS CROSSING ILLINOIS
EARLY THIS MORNING...PER WATER VAPOR IMAGERY. AREA OF LIGHT
SNOW...WHICH HAD PRODUCED A DUSTING...HAD LARGELY TAPERED IN
AREAS NORTH OF I-72. DID HAVE SOME LIGHT FREEZING DRIZZLE MIXED IN
EARLY ON AROUND PEORIA AND GALESBURG.

PRIMARY FORECAST ISSUES FOR THIS PACKAGE INVOLVE THE COLD AIR FOR
THIS WEEKEND...AS WELL AS PRECIPITATION CHANCES BEGINNING ON MONDAY.

SHORT TERM...TODAY THROUGH SATURDAY...

HIGH RESOLUTION MODELS STILL SHOWING LIGHT SNOW LINGERING OVER
THE EASTERN CWA EARLY THIS MORNING. REGIONAL RADAR LOOPS SHOWING
SOME PRECIPITATION STILL PRESENT AS FAR NORTH AS THE I-80
CORRIDOR IN NORTHEAST ILLINOIS...MOVING SOUTHWARD...SO THIS
SCENARIO SEEMS PLAUSIBLE. WILL KEEP 30-50 PERCENT POPS GOING EAST
OF I-57 EARLY THIS MORNING BEFORE TAPERING TO FLURRIES.
OTHERWISE...A QUIET PERIOD IS EXPECTED FROM LATE THIS AFTERNOON
THROUGH THURSDAY...AS HIGH PRESSURE DRIFTS SOUTHEAST INTO THE
TENNESSEE VALLEY.

THE COLD SNAP WHICH HAS BEEN ADVERTISED FOR THE LAST SEVERAL DAYS
IS STILL ON TRACK. 00Z MODELS IN GOOD AGREEMENT IN SWEEPING A COLD
FRONT ACROSS THE FORECAST AREA ON FRIDAY. THE FAR SOUTHEAST MAY
STAY IN THE WARMER AIR LONG ENOUGH TO REACH WELL INTO THE 40S...
BUT TEMPERATURES ELSEWHERE IN THE AFTERNOON WILL BE STEADY OR
FALLING. HAVE LOWERED TEMPERATURES FRIDAY NIGHT AND SATURDAY BY A
FEW MORE DEGREES FROM THE EARLIER VALUES. SOME OF THE GUIDANCE
SUGGESTS EVEN COLDER READINGS...BUT LACK OF SNOW COVER MAY HINDER
THAT THOUGHT. THE FRONT ITSELF IS LARGELY EXPECTED TO COME THROUGH
DRY IN OUR AREA...AND WILL ONLY GO WITH 20 POPS ACROSS THE EAST ON
FRIDAY MORNING.

LONG TERM...SUNDAY THROUGH TUESDAY...

TEMPERATURES ON SUNDAY EXPECTED TO STILL BE BELOW FREEZING IN MOST
AREAS...AS CENTER OF SURFACE HIGH MOVES OVER THE MISSISSIPPI
VALLEY. NEXT POINT OF CONCERN IS WITH A SHORTWAVE THAT WILL BE
MOVING OUT OF THE ROCKIES SUNDAY NIGHT. NARROW UPPER RIDGING WILL
OCCUR ACROSS THE PLAINS ON SUNDAY. THE ECMWF IS A BIT SLOWER THAN
THE GFS/CANADIAN MODELS IN BREAKING THIS RIDGE DOWN...MAINLY DUE
TO A DEEP TROUGH/CUTOFF LOW EXTENDING SOUTH FROM NOVA SCOTIA OVER
THE WESTERN ATLANTIC ON MONDAY. HAVE NOT MADE MUCH CHANGE IN THE
PRECIPITATION CHANCES FOR NOW...MAINLY IN THE SLIGHT CHANCE
RANGE...BUT MOST LIKELY PRECIPITATION OCCURRENCE LOOKS TO BE
MONDAY NIGHT IF IT DID OCCUR.

GEELHART

&&

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

&&

$$








AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

 1129 AM CST WED FEB 8 2012

.DISCUSSION...
356 AM CST

NEAR TERM CONCERNS THIS MORNING INCLUDE LIGHT SNOW ACROSS SOUTHERN
PARTS OF THE CWA...LINGERING LIGHT LAKE EFFECT SNOW THIS MORNING
OVER NORTHERN LAKE AND PORTER COUNTIES...AND CLOUD TRENDS ACROSS THE
AREA TODAY. LOOMING ON THE HORIZON IS A PUNCH OF ARCTIC AIR WHICH
ARRIVES FRIDAY...WITH THE FOCUS ON COLDER TEMPS AND THE POTENTIAL
FOR MORE SIGNIFICANT LAKE EFFECT SNOW ACROSS NORTHEAST IL AND
NORTHWEST INDIANA INTO SATURDAY.

LIGHT SNOW WAS OCCURRING EARLY THIS MORNING GENERALLY SOUTH OF A VYS
TO VPZ LINE...IN ASSOCIATION WITH AN UPPER DISTURBANCE MOVING ACROSS
DOWNSTATE IL INTO THE LOWER OHIO VALLEY. STRONGEST FORCING WITH THIS
SYSTEM WAS OCCURRING SOUTH OF THE CWA...WITH SFC OBS ACROSS OUR
SOUTHERN COUNTIES INDICATING  VISIBILITIES GENERALLY IN THE 3-7SM
RANGE AND SUGGESTING ONLY MINOR ACCUMULATIONS. LIGHT SNOW WILL
CONTINUE ACROSS THE SOUTH THIS MORNING...SHIFTING MAINLY EAST OF
INTERSTATE 57 BY 12Z. LITTLE ADDITIONAL ACCUMULATION IS EXPECTED.

FARTHER NORTH...A WEAK BAND OF LAKE EFFECT SNOW WAS IMPINGING ON
NORTHWEST LAKE COUNTY AND FAR SOUTHEAST COOK COUNTY. BAND WAS
HEAVIER FOR A TIME LATE LAST EVENING...WITH SOME ACCUMULATION NOTED
ON WEB CAMS ALONG THE INTERSTATES. RADAR RETURNS HAVE WEAKENED
CONSIDERABLY...AND HIGH RES MODEL GUIDANCE SEEMS TO HAVE CAPTURED
THIS TREND NICELY. BOTH RUC AND NAM DO INDICATE THAT SLIGHT COOLING
AROUND 900 HPA MAY SLIGHTLY IMPROVE THE LOW-LEVEL THERMODYNAMIC
PROFILE AROUND 12Z THIS MORNING...BEFORE EQUILIBRIUM HEIGHTS LOWER
BELOW 4000 FT AND LOW LEVEL WINDS BACK AROUND TO THE NORTHWEST BY
MIDDAY. THEREFORE EXPECT LIGHT SNOW SHOWERS TO CONTINUE THROUGH MID
MORNING...SHIFTING EAST AND WEAKENING WITH TIME IN THE 15-18Z
PERIOD. CURRENT WEB CAM VIEWS FROM 80/94 NEAR HAMMOND INDICATE
CURRENT ACTIVITY HAVING LITTLE/NO IMPACT ON VISIBILITY AT 330
AM...AND HAVE ONLY INCLUDED AN ADDITIONAL TENTH OF AN INCH OF
SNOWFALL THIS MORNING MAINLY ACROSS NORTHERN LAKE COUNTY...THOUGH
WILL MONITOR FOR ANY SIGNS OF BETTER DEVELOPMENT PRIOR TO SUNRISE.

GOES 11-3.9 MICRON IMAGERY SHOWS CLEARING OF LOW CLOUDS WAS
OCCURRING ACROSS FAR NORTHWEST IL EARLY THIS MORNING...THOUGH LOW
CLOUDS STRETCHED BACK ACROSS A LARGE PORTION OF CENTRAL IA. A SHORT
WAVE TROUGH DIGGING SOUTHEAST ACROSS THE HAWKEYE STATE MAY SLOW
CLEARING FOR A TIME THIS MORNING...BEFORE THE MID-LEVEL VORT AND
TROUGH AXIS PASS INTO CENTRAL IL EARLY THIS AFTERNOON. DRIER LOW
LEVEL AIR JUST UPSTREAM WILL ADVECT INTO THE AREA FROM THE NORTHWEST
HOWEVER WHICH SHOULD ALLOW CLEARING FROM THE NORTH/NORTHWEST THROUGH
THE DAY...WITH SOUTHEASTERN COUNTIES CLEARING LAST. MODEL
TIME/HEIGHT SECTIONS THEN APPEAR QUITE DRY TONIGHT THROUGH THURSDAY.
TEMPERATURE GUIDANCE IN FAIRLY CLOSE AGREEMENT DURING THIS PERIOD
AND GENERALLY USED A BLEND LEANING A LITTLE TOWARD THE COOLER
NUMBERS TODAY...AND TOWARD THE WARMER END OF THE RANGE WITH MORE SUN
AND WEAK WARM ADVECTION DEVELOPING THURSDAY.

GUIDANCE CONTINUES TO DEPICT SIGNIFICANT AMPLIFICATION OF THE UPPER
FLOW FOR THE END OF THE WEEK...WITH LARGE TROUGH DEVELOPING OVER
MUCH OF EASTERN NORTH AMERICA AND AT LEAST A TEMPORARY PUSH OF
ARCTIC AIR. MAIN AREA OF LOW PRESSURE IS PROGGED TO DEVELOP JUST
NORTH OF LAKE SUPERIOR ON THURSDAY AHEAD OF MID-LEVEL SHORT WAVE...
WITH UPPER WAVE AND SURFACE COLD FRONT PUSHING ACROSS THE FORECAST
AREA EARLY FRIDAY. MODELS INDICATE CONSIDERABLE DRY AIR IN THE
850-650 HPA LAYER PRECLUDING MUCH OF A PRECIPITATION THREAT...THOUGH
FAIRLY STRONG ISENTROPIC ASCENT IN THE WARM ADVECTION AHEAD OF THE
TROUGH MAY RESULT IN ENOUGH SATURATION IN THE 280-285 K LAYER TO
PRODUCE SOME FLURRIES FRIDAY MORNING. STRONG COLD ADVECTION ON
BLUSTERY NORTHERLY WINDS FRIDAY WILL LIKELY PRODUCE FALLING DAYTIME
TEMPS INTO THE 20S...WITH 850 HPA TEMPS FROM GFS/ECMWF DEPICTING -17
TO -19 C OVER THE AREA BY 12Z SATURDAY.

BESIDES THE COLD...THE REAL FORECAST CONCERN IN THE FRIDAY-SATURDAY
PERIOD IS THE POTENTIAL FOR LAKE EFFECT SNOW INTO NORTHEAST IL AND
NORTHWEST INDIANA. LAKE SURFACE TO 850 HPA DELTAS INCREASE INTO THE
LOW 20S LATE FRIDAY THROUGH SATURDAY MORNING...DURING A PERIOD IN
WHICH THE LOW LEVEL WINDS WILL BE NORTH-NORTHEAST DOWN THE FULL
FETCH OF THE LAKE. FORECAST SOUNDINGS INDICATE EQUILIBRIUM LEVELS
RISING TO NEAR 9000 FT BY 12Z SATURDAY...WITH LAKE INDUCED CAPES OF
400-500 J/KG. THIS WOULD SUGGEST THE POTENTIAL FOR SOME SIGNIFICANT
ACCUMULATING LAKE EFFECT FROM FRIDAY AFTERNOON THROUGH SATURDAY
MORNING. ONLY LIMITING FACTOR WOULD BE THE VERY DRY ARCTIC AIR
SPREADING ACROSS THE WESTERN LAKES...THOUGH THE LONG FETCH WILL
LIKELY PROVIDE ENOUGH MOISTURE FLUX TO MAKE UP FOR THE DRYNESS OF
THE AIRMASS. WILL BE INTERESTING TO SEE SOME OF THE HIGH RESOLUTION
GUIDANCE AS THE FRIDAY-SATURDAY PERIOD APPROACHES. FOR NOW HAVE
INCREASED POPS FOR THE LAKESIDE COUNTIES...AND WILL HIGHLIGHT
POTENTIAL FOR ACCUMULATING LAKE SNOWS IN THE HAZARDOUS WEATHER
OUTLOOK.

LONGER RANGE GUIDANCE IN A LITTLE BETTER AGREEMENT IN SHIFTING UPPER
TROUGH OFF TO THE EAST SUNDAY...AND BUILDING SURFACE HIGH PRESSURE
RIDGE IN FROM THE WEST SUNDAY NIGHT. WARM ADVECTION WORKS TO PUSH
THE ARCTIC AIR AWAY MONDAY AS LOW LEVEL WINDS SHIFT TO THE SOUTH.
BOTH OPERATIONAL ECMWF AND GFS INDICATE A SHORT WAVE LIFTING
NORTHEAST ACROSS THE REGION LATE MONDAY SUGGESTING POTENTIAL FOR
SOME LIGHT SNOW MONDAY NIGHT INTO TUESDAY...WITH TEMPS CLIMBING A
BIT BACK ABOVE NORMAL.

RATZER

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 18Z...

* NONE.

KJB

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

SKIES ARE IN THE PROCESS OF CLEARING ACROSS NORTHEASTERN ILLINOIS
AND NORTHWESTERN INDIANA LATE THIS MORNING. ONCE SKIES DO
CLEAR...THEY SHOULD REMAIN SO FOR THE REMAINED OF THE PERIOD.
SURFACE HIGH PRESSURE WILL DOMINATE ACROSS THE MID MISSISSIPPI
VALLEY THROUGH MUCH OF THURSDAY. THIS WILL CONTINUE TO SET UP WEST
TO SOUTHWESTERLY SURFACE FLOW ACROSS THE AREA. NO WEATHER CONCERNS
ARE EXPECTED IN THE NEXT 36 HOURS.

KJB


//ORD AND MDW CONFIDENCE...UPDATED 18Z...

* HIGH CONFIDENCE ON ALL FORECAST ELEMENTS.

KJB

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

THURSDAY NIGHT...VFR.
FRIDAY/SATURDAY...CHC LAKE EFFECT SNOW WITH MVFR/IFR POSSIBLE.
SUNDAY/MONDAY...VFR.
TUESDAY...SLT CHC RAIN/SNOW.
BMD

&&

.MARINE...
315 AM CST

FOLLOWING THE PASSAGE OF A COLD FRONT AND WITH HIGH PRESSURE
BUILDING ACROSS THE NORTHERN PLAINS AND UPPER MISSISSIPPI
VALLEY...WINDS WILL GRADUALLY DIMINISH. AS THE HIGH PRESSURE SAGS
TO THE SOUTHEAST WEDNESDAY AND THURSDAY...WINDS WILL BECOME
WESTERLY TO 25KT AND EVENTUALLY SOUTHWESTERLY...AS ANOTHER ARCTIC
COLD FRONT APPROACHES. THIS FRONT WILL PUSH ACROSS THE LAKE
THURSDAY NIGHT. A STRONG PUSH OF COLD AIR MAY BRING WINDS UP TO
GALE FORCE OVER THE FAR NORTHERN PORTIONS OF THE LAKE LATE
THURSDAY INTO THURSDAY NIGHT.

KREIN

&&

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

$$






AREA FORECAST DISCUSSION

NWS QUAD CITIES IA IL

 305 PM CST WED FEB 8 2012

.SYNOPSIS...
12Z UA ANALYSIS  HAS A RIDGE RUNNING FROM THE GULF COAST INTO
EASTERN MONTANA. ARCTIC AIR WAS OVER NORTHERN CANADA WITH THE
SOUTHERN EXTENT DOWN TO JAMES BAY. SATELLITE TRENDS THROUGH MID
AFTERNOON HAD STRATUS TRAPPED UNDER AN INVERSION FROM THE PLAINS
INTO CENTRAL ILLINOIS AND SOUTHEAST IOWA. THE 18Z SFC ANALYSIS HAD
THE RIDGE FROM THE DAKOTAS INTO TEXAS. A WEAK TROF RAN FROM THE
NORTHERN GREAT LAKES INTO WESTERN WISCONSIN. DEW POINTS WERE
GENERALLY IN THE TEENS AND 20S ACROSS MUCH OF THE MIDWEST WITH 30S
IN THE SOUTHERN PLAINS AND OHIO VALLEY.

&&

.SHORT TERM...TONIGHT AND THURSDAY...
THE SHALLOW LAYER OF STRATUS CLOUDS BELOW THE TRAPPING INVERSION IS
NOT BEING HANDLED AT ALL BY THE MODELS. DIURNAL HEATING FROM THE SUN
HAS STRENGTHENED THE INVERSION ABOVE THE CLOUDS CAUSING THE OVERALL
CLEARING TREND TO SLOW.

THE 950MB RH LEVEL ON THE RUC HAS DONE REASONABLY WELL IN DEPICTING
WHERE THE CLOUDS CURRENTLY ARE. USING THE RUC 950MB RH TRENDS
COMBINED WITH EXTRAPOLATION OF SATELLITE INDICATES THAT THE CLOUDS
WILL REMAIN ACROSS ROUGHLY THE SOUTHERN 40 PERCENT OF THE CWFA FOR
THE REMAINDER OF THE AFTERNOON. CLEARING IN THE SOUTH THIRD OF THE
CWFA WILL BE SLOW DURING THE EVENING BUT CLEAR SKIES SHOULD BE SEEN
ACROSS NEARLY ALL THE CWFA BY MIDNIGHT.

AFTER MIDNIGHT ANOTHER UPPER LEVEL DISTURBANCE APPROACHES. THIS
DISTURBANCE SHOULD JUST PASS THROUGH WITH NO NOTICEABLE AFFECTS.
HOWEVER...IF THE LOW CLOUDS ARE STILL IN PLACE ACROSS THE SOUTH
THIRD OF THE CWFA THEN ISOLATED FLURRIES WOULD BE POSSIBLE. FOR NOW
IT APPEARS THAT THE LOW CLOUDS SHOULD EXIT THE CWFA AROUND OR
SHORTLY AFTER MIDNIGHT. ASSUMING CLOUDS CLEAR TONIGHT...TEMPERATURES
SHOULD BE QUITE CHILLY.

THE CLEAR SKIES ON THURSDAY WILL GIVE WAY TO MORE CLOUDS THROUGH THE
DAY. THE 950MB RH FIELD FROM THE WRF...ALTHOUGH NOT AS GOOD THE
RUC...HAS A STRONG SIGNAL INDICATING THE LOW CLOUDS IN NEBRASKA/
KANSAS WILL ADVECT BACK INTO THE CWFA DURING THE MORNING HOURS. CLOUD
COVER FOR THURSDAY HAS BEEN INCREASED BUT IT IS LIKELY TOO LOW. THERE
IS SOME WEAK F VECTOR CONVERGENCE ACROSS THE AREA WHICH COULD PROMOTE
THE DEVELOPMENT OF FLURRIES. HOWEVER...FORCING IS WEAK TO NON-
EXISTENT SO THE CHANCES OF FLURRIES SHOULD BE VERY LOW. THE ARRIVAL
OF CLOUDS ON THURSDAY SHOULD AID IN SUPPRESSING TEMPERATURES.
..08..


.LONG TERM...THURSDAY NIGHT THROUGH NEXT WEDNESDAY...
THURSDAY NIGHT AND FRIDAY...DIGGING UPPER TROF ACRS CENTRAL CANADA
AND INTO THE WESTERN GRT LKS STILL ON TRACK TO SHUNT AN ARCTIC
FRONT THROUGH THE CWA BY FRI MORNING. VARYING AMOUNTS OF STRATUS
AHEAD OF THIS PROCESS THU EVENING...AND PRE-FRONTAL SOUTHWEST SFC
FLOW MAY HELP TEMPS FROM BOTTOMING OUT THU NIGHT BUT MAY STILL LEAN
TOWARD THE COOLER SIDE OF GUIDANCE AS A BUFFER AGAINST SOME SFC WIND
DECOUPLE IN A DRY SFC LAYER. STEEPENING CYCLONIC FLOW IN A POST-
FRONTAL REGIME AND VORT SPOKE WILL LOOK TO WRING OUT LIGHT SNOW AND
FLURRIES OUT OF ANY POST-FRONTAL STRATUS ON FRI. BREAKS IN CLOUD
COVER AND PROJECTED STEEP LLVL LAPSE RATES MAY MAKE FOR MORE OF A
DIURNAL SNOW SHOWER ACTIVITY AS OPPOSED TO STRATIFORM SNOW ESPECIALLY
ACRS THE NORTHEAST TO EASTERN HALF OF THE DVN CWA. COLD AND BLUSTERY
POST-FRONTAL CONDITIONS WITH HIGHS IN MAINLY IN THE 20S AND
NORTHWEST WINDS OF 15 TO 25 MPH. CLEAR OUT FRI NIGHT AS STRONG 1040+
MB HIGH PRESSURE COMPLEX BUILDS DOWN ACRS THE PLAINS AND UPPER MS RVR
VALLEY INTO SAT MORNING.WITH EXTENT OF INCOMING SFC RIDGE PRESSURE
GRADIENT...EXPECT SOME MIXING NORTH WINDS TO MAINTAIN OVERNIGHT FRI
INTO EARLY SAT MORNING TO PREVENT A BOTTOM OUT IN THE LOW SINGLE
DIGITS OR EVEN BELOW ZERO. MAY STILL GO WITH LOW SINGLE DIGITS IN THE
FAR NORTHWESTERN CWA...TO THE LOWER TEEN IN THE SOUTHEAST.

SATURDAY AND SUNDAY...SREF AND LATEST SUITE OF 12Z RUN MEDIUM RANGE
MODELS IN GOOD AGREEMENT OF SUGGESTING BOUT OF RIDGING TO MAKE FOR A
FAIR BUT CHILLY WEEKEND. BRUNT OF HIGH PRESSURE CENTER PROJECTED TO
SHUTTLE TO THE SOUTH OF THE AREA ACRS THE LOWER MS RVR VALLEY ON SAT
WITH RIDGE LOBE EXTENDING THIS FAR NORTH. MAINLY SUNNY SKIES...LACK
OF SNOW COVER AND CONTINUED MIXING NORTHWEST WINDS OF 10-20 MPH
THROUGH AT LEAST MID AFTERNOON WILL HELP TEMPS GET INTO THE LOW TO
MID 20S...OTHERWISE EXTENT OF COLD AIRMASS IN PLACE WOULD WARRANT
HIGHS IN THE TEENS. SAT NIGHT MAY BE THE COLDEST NIGHT/SECOND NIGHT
AFTER COLD FRONT RULE. CHANCE OF NEAR ZERO OR SUB-ZERO TEMPS IN
NORTHERN PORTIONS OF THE CWA ESPECIALLY IN COLD AIR DRAINAGE
LOCALS. LIGHT RETURN FLOW BEHIND PASSING RIDGE AXIS TO HELP TEMPS
ON SUNDAY REACH THE MID TO UPPER 20S...BUT EXPECT INCREASING HIGH
CLOUDS IN THE AFTERNOON AHEAD OF SOUTHERN STEAM WAVE DEVELOPING
ACRS THE EASTERN GRT BSN. DEPENDING ON EXITING TIMING OF THE ROBUST
HIGH PRESSURE COMPLEX...FIRST BOUT OF OVERRUNNING SNOWS MAY GET CLOSE
TO OR EVEN INTO THE WESTERN CWA LATE SUNDAY NIGHT BUT FOR NOW WILL
BANK ON THE STRENGTH AND SLOWNESS OF THE DENSE RIDGE.

MONDAY THROUGH WEDNESDAY...BOTH THE 12Z RUN GFS AND ECMWF ARE
TRENDING TOWARD ROLLING A LARGE CHUNK OF THE SOUTHERN STREAM WAVE
OUT OVER THE REGION MON INTO TUE MORNING. SOME MOISTURE DRAW IN
INCREASING WARM MOIST CONVEYOR UP OFF THE WESTERN GULF BEHIND
RETREATING RIDGE COMPLEX WILL FUEL ANY ISENTROPIC LIFT OR ELEVATED
FORCES AHEAD OF THIS WAVE. EARLY INDICATIONS BY LATEST 12Z RUN
MODELS ESPECIALLY THE WETTER ECMWF NOW SUGGEST 2-4 INCHES OF SNOW
POSSIBLE ON MONDAY AND INTO MONDAY NIGHT. WILL CONTINUE TO TREND
UP THE POPS BUT SOME TIMING AND MOISTURE INFLUX STILL YET TO EB
REFINED OVER THE NEXT 24-48 HRS. WITH THE CURRENT EXPECTED TIMING...
SNOW SHOULD BE EAST OF THE CWA BY TUE MORNING AND WILL GO DRY WITH
WAKE RIDING. SOUTHWESTERN TROF/SOUTHERN STEAM RELOADS BY MID NEXT
WEEK WITH ANOTHER EVEN LARGER SYSTEM POSSIBLE WED THROUGH THU
DEPENDING ON PHASING OF COURSE.    ..12..

&&

.AVIATION...
SATELLITE TRENDS INDICATE THE CLEARING WILL BE SLOWER THAN THOUGHT
IN THE 18Z TAFS. EXTRAPOLATION OF SATELLITE COMBINED WITH RUC TRENDS
SUGGEST VFR CONDITIONS WILL NOT DVLP AT KBRL UNTIL CLOSER TO 06Z/09.
VFR CONDITIONS WILL CONTINUE AT KDBQ AND WILL OCCUR 21Z/08-00Z/09 AT
KCID/KMLI. THERE MAY BE A POTENTIAL FOR SOME MVFR VSBYS PRIOR TO
SUNRISE AT ALL TAF SITES. MVFR CIGS ARE EXPECTED TO MOVE INTO ALL
TAF SITES AFT 14Z/09.    ..08..

&&

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

&&

$$

08/12





AREA FORECAST DISCUSSION

NWS QUAD CITIES IA IL

 1242 PM CST WED FEB 8 2012

.UPDATE...
DIURNAL HEATING FROM THE STRONGER SUN HAS RESULTED IN A SLOWING OF
THE LOW CLOUD MOVEMENT. EXTRAPOLATION OF CURRENT SATELLITE TRENDS
MAKES CLEARING BEFORE SUNSET IN THE SOUTHERN CWFA QUESTIONABLE.
THE NEWEST RUC TRENDS WOULD ALSO QUESTION THE OVERALL CLEARING IN
THE SOUTH THIS AFTERNOON AS WELL.

THEREFORE...WILL UPDATE THE FCST TO SLOW DOWN THE CLEARING IN THE
SOUTHERN CWFA TO OCCUR AFTER SUNSET. TEMPERATURES HAVE BEEN
ADJUSTED AS WELL TO REFLECT THE SLOWER CLOUD MOVEMENT.
..08..

&&

.PREV DISCUSSION... /ISSUED 1122 AM CST WED FEB 8 2012/

AVIATION...
THE MODELS ARE NOT HANDLING THE SHALLOW CLOUD LAYER TRAPPED BELOW
THE INVERSION. A COMBINATION OF EXTRAPOLATION AND THE RUC WERE
USED TO HANDLE THE MVFR CIGS. KCID/KMLI ARE ON THE EDGE OF THE
MVFR CIGS BUT SHOULD GO VFR PRIOR TO 00Z/09. A THIN SPOT IN THE
CLOUDS HAS ALLOWED KBRL TO GO VFR BUT WILL LIKELY GO BACK TO MVFR
WITH VFR CONDITIONS DVLPG AFT 00Z/09. BASED ON LOW LEVEL FLOW THE
MVFR CIGS IN NEBRASKA/KANSAS WILL ADVECT BACK INTO
KCID/KDBQ/KMLI/KBRL AFT 12Z/09.
.08..

PREV DISCUSSION... /ISSUED 1019 AM CST WED FEB 8 2012/

UPDATE...
CLOUDS ARE TRAPPED UNDER THE INVERSION IN A VERY THIN LAYER.
A MIX OF THE DVN AND ILX 12Z SOUNDINGS IS LIKELY MORE INDICATIVE
OF THE OVERALL ENVIRONMENT. SATELLITE TRENDS THE PAST FEW HOURS
SHOWS A SLOW DRIFT AROUND 10 KTS WITH THE TRAPPED STRATUS TO THE
SOUTHEAST. A SPOTTER HAS REPORTED SOME VERY LIGHT FLURRIES IN
NORTHEAST MISSOURI UNDER THE STRATUS. THIS REPORT MAKES SENSE AS A
SLOW TOP DOWN DRYING OF THE LOWEST LAYERS OCCUR AND WITH THE
PASSAGE OF A VORT MAX/DISTURBANCE IN THAT AREA.

THE FCST IS BEING UPDATED TO BETTER REFLECT CURRENT CLOUD TRENDS
BASED ON EXTRAPOLATION AND SOME INPUT FROM THE RUC. ISOLD FLURRIES
ARE ALSO BEING ADDED IN THE FAR SOUTHERN PARTS OF THE CWFA TO
ACCOUNT FOR THE PASSING VORT MAX. SINCE THE CLOUDS WILL HOLD
AROUND LONGER IN THE SOUTH...TEMPERATURES THERE HAVE BEEN LOWERED
A LITTLE. THERE SHOULD STILL BE A SMALL POP IN TEMPERATURES AS
THE CLOUDS CLEAR LATE THIS AFTERNOON.

AN UPDATED FCST WILL BE OUT BY 1030 AM.
08..

&&

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

$$






AREA FORECAST DISCUSSION

NWS QUAD CITIES IA IL

 1122 AM CST WED FEB 8 2012

.AVIATION...
THE MODELS ARE NOT HANDLING THE SHALLOW CLOUD LAYER TRAPPED BELOW
THE INVERSION. A COMBINATION OF EXTRAPOLATION AND THE RUC WERE
USED TO HANDLE THE MVFR CIGS. KCID/KMLI ARE ON THE EDGE OF THE
MVFR CIGS BUT SHOULD GO VFR PRIOR TO 00Z/09. A THIN SPOT IN THE
CLOUDS HAS ALLOWED KBRL TO GO VFR BUT WILL LIKELY GO BACK TO MVFR
WITH VFR CONDITIONS DVLPG AFT 00Z/09. BASED ON LOW LEVEL FLOW THE
MVFR CIGS IN NEBRASKA/KANSAS WILL ADVECT BACK INTO
KCID/KDBQ/KMLI/KBRL AFT 12Z/09.
..08..

&&

.PREV DISCUSSION... /ISSUED 1019 AM CST WED FEB 8 2012/

UPDATE...
CLOUDS ARE TRAPPED UNDER THE INVERSION IN A VERY THIN LAYER.
A MIX OF THE DVN AND ILX 12Z SOUNDINGS IS LIKELY MORE INDICATIVE
OF THE OVERALL ENVIRONMENT. SATELLITE TRENDS THE PAST FEW HOURS
SHOWS A SLOW DRIFT AROUND 10 KTS WITH THE TRAPPED STRATUS TO THE
SOUTHEAST. A SPOTTER HAS REPORTED SOME VERY LIGHT FLURRIES IN
NORTHEAST MISSOURI UNDER THE STRATUS. THIS REPORT MAKES SENSE AS A
SLOW TOP DOWN DRYING OF THE LOWEST LAYERS OCCUR AND WITH THE
PASSAGE OF A VORT MAX/DISTURBANCE IN THAT AREA.

THE FCST IS BEING UPDATED TO BETTER REFLECT CURRENT CLOUD TRENDS
BASED ON EXTRAPOLATION AND SOME INPUT FROM THE RUC. ISOLD FLURRIES
ARE ALSO BEING ADDED IN THE FAR SOUTHERN PARTS OF THE CWFA TO
ACCOUNT FOR THE PASSING VORT MAX. SINCE THE CLOUDS WILL HOLD
AROUND LONGER IN THE SOUTH...TEMPERATURES THERE HAVE BEEN LOWERED
A LITTLE. THERE SHOULD STILL BE A SMALL POP IN TEMPERATURES AS
THE CLOUDS CLEAR LATE THIS AFTERNOON.

AN UPDATED FCST WILL BE OUT BY 1030 AM.
.08..

&&

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

$$






AREA FORECAST DISCUSSION

NWS GOODLAND KS

 255 PM MST WED FEB 8 2012

.DISCUSSION...
235 PM MST WED FEB 8 2012

TONIGHT...SHORTWAVE TROUGH PASSES JUST NORTH OF CWA OVERNIGHT. A
WARM FRONT ON THE BACK SIDE OF THIS FEATURE WILL LIFT NORTHEAST
ACROSS THE CWA 00-06Z...WITH SURFACE HIGH PRESSURE CENTER SHIFTING
EAST TOWARDS NORTHERN MISSOURI. NAM IS SHOWING MODERATE AMOUNT OF
MID LEVEL MOISTURE OVER EASTERN CWA THIS EVENING...POSSIBLY
SUPPORTING A FEW FLURRIES. NOT REALLY CONFIDENT IN THIS. LOW STRATUS
CONTINUES TO LINGER ACROSS MOST OF THE CWA ALONG THE EASTERN EDGE OF
THIS SURFACE HIGH. AS WARM FRONT LIFTS ACROSS AREA NAM/GFS SHOW BL
MOISTURE DECREASING FROM THE WEST TO THE EAST...WITH STRATUS
POSSIBLY LINGERING OVER EASTERN LOCATIONS. LATEST HRRR BEGINNING TO
SHOW FOG DEVELOPMENT AHEAD OF THIS FRONT DURING THE EVENING
HOURS...WITH RUC FAVORING STRATUS. I WASNT CONFIDENT ENOUGH TO ADD
FOG MENTION DURING THIS CYCLE...THOUGH THERE COULD BE A BRIEF
WINDOW.

FRIDAY THROUGH TUESDAY...FORECAST CONCERNS THROUGH THE END OF THE WEEK
AND INTO THE FIRST PART OF NEXT WEEK ARE TEMPERATURES.

NORTHWEST FLOW WILL PERSIST ALOFT ACROSS THE REGION THROUGH
SATURDAY WITH A SHORT WAVE RIDGE MOVING EAST OF THE ROCKIES AND
ACROSS THE CENTRAL PLAINS SATURDAY NIGHT AND SUNDAY. AT THE
SURFACE...A TROUGH MOVES ACROSS THE REGION ON FRIDAY WITH COLDER
AIR BEGINNING TO MOVE INTO THE PLAINS STATES AND BACKING INTO THE
CENTRAL HIGH PLAINS REGION FRIDAY THROUGH FRIDAY NIGHT AND
SATURDAY. AS THIS COLD AIR IS MOVING INTO THE REGION...A WEAK
DISTURBANCE IN THE NORTHWEST FLOW MAY CREATE SOME VERY LIGHT SNOW
IN THE VICINITY OF THE FRONTAL BOUNDARY PUSHING WESTWARD. THERE
MAY BE A POSSIBILITY OF SOME LIGHT FREEZING PRECIPITATION AS IT
INITIATES GIVEN THE MODEL SOUNDINGS WERE HINTING AT WARMER AIR
ALOFT WITH A SHALLOW COLD LAYER AT THE SURFACE...BUT CONFIDENCE AT
THIS POINT IS LOW IN THIS OCCURRING AND HAVE KEPT IT AS ALL LIGHT
SNOW.

A SERIES OF SHORT WAVE TROUGHS MOVES THROUGH THE FLOW LATE IN THE
WEEKEND AND INTO THE BEGINNING OF NEXT WEEK...SO HAVE KEPT AT LEAST
A SLIGHT CHANCE OF VERY LIGHT SNOW IN THE FORECAST THROUGH SUNDAY
NIGHT. HAVE A BRIEF BREAK MONDAY AS A SHORT WAVE RIDGE MOVES
ACROSS THE FORECAST AREA WITH MORE LIGHT SNOW ON TUESDAY WITH THE
NEXT SHORT WAVE TROUGH.

LOCKHART
&&

.AVIATION...
1018 AM MST WED FEB 8 2012

FOR THE 18Z TAFS...LOW STRATUS CONTINUES TO LINGER OVER BOTH KMCK
AND KGLD TERMINALS AT TAF ISSUANCE...WITH MVFR CIGS PREVAILING. CANT
RULE OUT BRIEF PERIODS OF IFR DURING FIRST 6HR OF TAF
PERIOD...HOWEVER OVERALL TREND HAS BEEN TOWARDS CIGS AROUND 1200 FT
AGL. FOR KGLD...LATEST SHORT RANGE GUIDANCE SHOWS CIGS IMPROVING TO
VFR LATER THIS AFTERNOON AS LOW STRATUS SHIFTS EAST. WITH SURFACE
HIGH PRESSURE STILL LINGERING OVER CENTRAL KANSAS/NEBRASKA
TONIGHT...LOW CIGS MAY LINGER THROUGH OVERNIGHT PERIOD AT KMCK. FOR
NOW HAVE GONE WITH TRENDS FROM LATEST 12Z GUIDANCE SHOWING VFR AT
KMCK AROUND 08Z. DAYTIME WINDS AT KGLD WILL REMAIN OUT OF SOUTH
AROUND 10KT TODAY AND OUT OF THE W/NW TOMORROW. OTHERWISE...LIGHT
AND VARIABLE WINDS ARE EXPECTED.

DR
&&

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

$$








AREA FORECAST DISCUSSION

NWS WICHITA KS

 315 PM CST WED FEB 8 2012

.DISCUSSION...

MAIN FORECAST CHALLENGES WILL BE TEMPS FOR THE WEEKEND WITH OUR NEXT
POLAR SURGE WITH ATTENTION TURNING TO PRECIP CHANCES AND TYPE FOR
SUN-MON.

SYNOPSIS:
ONE SHORTWAVE IS TRACKING EAST OVER THE OHIO VALLEY WITH ANOTHER PIECE
OF ENERGY DIVING SOUTHEAST OVER WESTERN SD/NW NEBRASKA. MEANWHILE
ANOTHER UPPER IMPULSE EXTENDS OVER THE NORTHERN INTERMOUNTAIN INTO
THE CENTRAL GREAT BASIN. AT THE SURFACE THE HIGH IS CENTERED OVER NW
MO/SW IA WITH SOME RETURN FLOW COMMENCING OVER THE HIGH PLAINS.

TONIGHT-THU:
THE SHORTWAVE ENERGY OVER THE DAKOTAS IS EXPECTED TO MAINTAIN ITS
QUICK SOUTHEAST PROGRESSION AND WILL BE OVER THE MISSOURI VALLEY BY
THU MORNING. AT THE SAME TIME ADDITIONAL UPPER ENERGY WILL MOVE INTO
THE SOUTHERN ROCKIES BY THU MORNING. THIS FEATURE WILL SPREAD PRECIP
CHANCES OVER THE SOUTHERN PLAINS. HOWEVER AT THIS TIME FEEL
CONFIDENT ENOUGH IN THE PRECIP STAYING SOUTH TO KEEP OUT OF THE
FORECAST FOR NOW. A BRIEF WARMUP WILL AFFECT THE AREA THU WITH A RETURN
TO MORE SEASONAL TEMPS.

FRI-SAT:
THE MAIN THEME THROUGH THESE PERIODS WILL BE FOR ARCTIC AIR TO
INVADE THE AREA.

SHORTWAVE ENERGY IS EXPECTED TO DIVE OUT OF ALBERTA/SASKATCHEWAN AND
INTO THE NORTHERN PLAINS THU NIGHT. THIS WILL PULL THE POLAR VORTEX
TO THE SOUTHWEST WHICH WILL ALLOW SOME VERY COLD AIR TO SPILL SOUTH
ON FRI WITH THE FRONT PASSING THROUGH THE FORECAST AREA DURING THE
DAY. CONFIDENCE IS VERY HIGH THAT WELL BELOW NORMAL TEMPS WILL BE IN
PLACE FOR BOTH FRI AND ESPECIALLY SAT WHICH AGREES WELL WITH FORECASTED
STANDARDIZED ANOMALIES.

SUN-WED:
THE FOCUS OF THESE PERIODS WILL BE A FAST MOVING WAVE THAT IS
EXPECTED TO SPREAD SOME PRECIP ACROSS THE AREA FOR THE SUN NIGHT-MON
TIME FRAME. BOTH THE GFS AND ECMWF AGREE ON TRACKING THIS SYSTEM
ACROSS THE DESERT SW ON SUN AND KICKING OUT INTO THE SOUTHERN HIGH
PLAINS ON SUN NIGHT. THIS WILL PLACE THE BEST LIFT OVER THE AREA FOR
SUN NIGHT INTO MON. THE MAIN QUESTION WILL BE PRECIP TYPE. THE
EXPECTED SETUP IS TYPICALLY NOT CONDUCIVE FOR A WIDESPREAD FREEZING
RAIN WITH THE LACK OF NEUTRAL OR COLD ADVECTION UNDER THE SW
FLOW ALOFT. THE PROGRESSIVE NATURE OF THIS SYSTEM ALSO DOES NOT
FAVOR A WIDESPREAD FREEZING RAIN EPISODE. CURRENT THINKING IS THAT WE
COULD BE LOOKING AT AN ADVISORY TYPE EVENT WITH SNOW THE PREDOMINANT
PRECIP TYPE.

MEDIUM RANGE MODELS ARE FORECASTING ANOTHER SHORTWAVE TO KICK OF THE
ROCKIES ON TUE NIGHT INTO WED. HOWEVER THERE IS CONSIDERABLE
DIFFERENCES BETWEEN THE GFS AND ECMWF WITH REGARDS TO TIMING WITH
THE GFS MUCH MORE PROGRESSIVE.

&&

.FIRE WEATHER...
FIRE DANGER CONCERNS ARE EXPECTED TO REMAIN MINMAL FOR THE NEXT
COULE OF DAYS. RH`S ARE EXPECTED TO REMAIN ELEVATED FOR BOTH THU
AND FRI DUE TO TEMPS NOT CLIMBING MUCH ABOVE NORMAL. WINDS FOR THU
WILL TURN TO THE WEST AND SOUTHWEST BUT WILL REMAIN LIGHT...IN THE
8-11 MPH RANGE. A VERY STRONG COLD FRONT WILL PASS THROUGH THE
AREA ON FRI WITH WIND FLIPPING AROUND TO THE NORTH.

LAWSON

&&

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

MAIN AVIATION CONCERN/CHALLENGE WILL BE TIMING DISSIPATION OF LOW
CLOUDS. SOME HINTS ON VISIBLE SATELLITE THAT THIS IS ALREADY
TRYING TO OCCUR OVER WESTERN PORTIONS OF KS AND OK.
ADDITIONALLY...NAM/GFS MODELS BOTH CLEAR CLOUDS OUT THIS
AFTERNOON. HOWEVER...THINKING THE MORE PESSIMISTIC RUC MODEL HAS
THE BEST FORECAST...HOLDING LOW MVFR CIGS ACROSS THE AREA WELL
INTO THIS EVENING. THIS MAKES SENSE GIVEN INCREASING UPPER LEVEL
CLOUDS ALONG WITH WEAK BOUNDARY LAYER FLOW. IN FACT...WOULDN`T BE
SURPRISED IF MVFR CIGS HANG TOUGH ALL NIGHT...DUE TO WARM
ADVECTION INCREASING AND STRENGTHENING THE INVERSION. FOR
NOW...WENT LOW MVFR THROUGH 00Z THIS EVENING...AND THEN RAISED
EVERYONE UP ABOVE 2000 FT AGL...ALTHOUGH CIGS COULD REMAIN BELOW
2000 FT ALL NIGHT.

ADK

&&

.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT    24  47  25  38 /   0  10  10   0
HUTCHINSON      23  47  24  35 /   0   0   0   0
NEWTON          24  47  24  35 /   0   0   0   0
ELDORADO        24  47  25  37 /   0   0  10   0
WINFIELD-KWLD   25  49  28  41 /   0  10  10  10
RUSSELL         18  40  19  31 /   0   0   0   0
GREAT BEND      20  43  21  33 /   0  10  10   0
SALINA          22  43  22  33 /   0   0   0   0
MCPHERSON       23  46  23  34 /   0   0   0   0
COFFEYVILLE     27  49  33  43 /   0  10  10  10
CHANUTE         25  48  29  39 /   0   0  10  10
IOLA            24  48  28  38 /   0   0   0  10
PARSONS-KPPF    26  49  31  41 /   0   0  10  10

&&

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

$$








AREA FORECAST DISCUSSION

NWS TOPEKA KS

 1133 AM CST WED FEB 8 2012

...UPDATE TO AVIATION...

.DISCUSSION...
09Z WATER VAPOR SHOWS SEVERAL SHORTWAVE WITH ONE MOVING EAST OF THE
FORECAST AREA...A SECOND CLOSED CIRCULATION OVER MT...AND A THIRD
WAVE OFF THE SOUTHERN CA COAST. MEANWHILE SFC OBS SHOW A COLD SFC
RIDGE OF HIGH PRESSURE NOSING INTO CENTRAL KS.

FOR TODAY THROUGH THURSDAY...THE FORECAST AREA SHOULD REMAIN UNDER
THE INFLUENCE OF NORTHWEST FLOW WITH THE WAVE OVER MT EVENTUALLY
SHEARING OUT AND MOVING TO THE EAST. THE SFC RIDGE BUILDING INTO
CENTRAL KS NOW WILL LIMIT ANY DEEP MOISTURE SO THE FORECAST REMAINS
DRY. THE MOST UNCERTAIN PART OF THE FORECAST IS WITH THE LOW CLOUDS.
THE NAM AND RUC ARE SUGGESTING THE STRATUS COULD HANG AROUND FOR A
GOOD CHUNK OF THE DAY. SO WITH MOSTLY CLOUDY TO OVERCAST SKIES AND
CONTINUED COLD AIR ADVECTION...TODAY`S HIGHS WILL NOT WARM UP MUCH.
WE SHOULD SEE SOME RETURN FLOW AND SUNSHINE FOR THURSDAY AS THE SFC
RIDGE MOVES EAST OF THE AREA. THIS SHOULD ALLOW FOR HIGHS TO WARM
INTO THE 40S.

THURSDAY NIGHT WILL SEE PERHAPS THE STRONGEST COLD FRONT IN TERMS OF
COLD AIR SO FAR THIS WINTER...AS AN ARCTIC AIRMASS BUILDS SOUTH
THROUGH THE PLAINS FOR FRIDAY AND SATURDAY. THE MODEL CONSENSUS IS
FOR STRONG COLD AIR ADVECTION TO OCCUR BEHIND THE FRONT THROUGH
SATURDAY. TO MAKE THINGS WORSE...THE COLD AIR WILL BE MOVING OVER
THE SNOWPACK ACROSS CENTRAL NEB. SO HAVE LOWERED TEMPS FOR FRIDAY
AND SATURDAY. TEMPS ON SATURDAY ARE NOT EXPECTED TO MAKE IT OUT OF
THE 20S. THE MODELS ARE SHOWING SOME MID LEVEL FRONTOGENESIS ON THE
WESTERN EDGE OF THE UPPER TROUGH FOR FRIDAY NIGHT AND SATURDAY. THIS
FRONTOGENESIS IS COINCIDENTAL WITH A NARROW AXIS OF MID LEVEL
MOISTURE. THE GFS AND ECMWF TEND TO KEEP THIS BAND JUST TO THE WEST
OF THE FORECAST AREA SO HAVE NOT INCLUDED ANY POPS AT THIS TIME.
HOWEVER WILL MENTION A SLIGHT CHANCE FOR SOME FLURRIES IN PARTS OF
NORTH CENTRAL KS ON SATURDAY.

THE MAKINGS OF A WINTER STORM APPEAR TO BE COMING TOGETHER FOR
SUNDAY NIGHT INTO MONDAY MORNING. THE MEDIUM RANGE MODELS ARE IN
REASONABLE AGREEMENT THAT A SHORTWAVE WILL MOVE FROM THE PACIFIC
INTO THE PLAINS AS THE HIGH AMPLITUDE UPPER RIDGE OVER THE WEST
COAST BREAKS DOWN. BUFKIT SOUNDINGS SHOW THE COLUMN SATURATING WITH
ANY WARM NOSE DUE TO WARM AIR ADVECTION SUNDAY NIGHT INCREASING TO
ONLY ABOUT +1C. THIS SHOULD NOT BE ENOUGH TO MELT ANY SNOW
COMPLETELY...AND THINK THE PREDOMINANT PRECIP TYPE SHOULD BE SNOW.
HOWEVER THE MID LEVEL WARM AIR ADVECTION SHOULD BRING PLENTY OF
MOISTURE TO GO ALONG WITH THE REASONABLE FORCING OF THE UPPER WAVE.
BECAUSE OF THIS HAVE INCREASED POPS FOR SUNDAY NIGHT AND MONDAY. QPF
FORECASTS FROM THE ECMWF AND GFS SUGGEST THAT THERE COULD BE A
COUPLE INCHES OF SNOW...WHICH IS IN LINE WITH THE MODEST FORCING
PROVIDED BY THE OPEN WAVE. IF PRECIP HANGS ON LONG ENOUGH INTO THE
DAY MONDAY...WARM AIR ADVECTION MAY BE STRONG ENOUGH TO CAUSE THE
PRECIP TO CHANGE OVER TO LIQUID BY MONDAY AFTERNOON. WHILE THINGS
ARE FAR FROM CERTAIN...THIS SYSTEM BARES WATCHING AS IT GETS CLOSER.

THE MODELS PROG AN ACTIVE WEATHER PATTERN FOR NEXT WEEK AS A SECOND
WAVE LIFTS OUT INTO THE PLAINS ON TUESDAY. THERE SEEMS TO BE SOME
AGREEMENT IN THE TIMING OF THIS SECOND WAVE. ALTHOUGH THERE IS SOME
DISAGREEMENT IN THE TRACK OF THIS WAVE. REGARDLESS BOTH MODELS...
ESPECIALLY THE ECMWF WITH ITS NORTHERN TRACK...BRING ENOUGH WARM AIR
NORTH INTO EASTERN KS THAT PRECIP SHOULD BE ALL RAIN. IF THE SYSTEM
IS ABLE TO BRING ENOUGH WARM AIR NORTH...THERE COULD EVEN BE ENOUGH
INSTABILITY FOR SOME CONVECTION. AGAIN THIS WILL NEED TO BE WATCHED
IN LATER RUNS. AT THIS POINT...THE FORECAST HAS MODERATING TEMPS
INTO TUESDAY WITH A CHANCE FOR SOME RAIN.

WOLTERS


&&

.AVIATION...

MVFR CIGS ARE HOLDING STRONG OVER TAF SITES WITH ONLY A FEW
TEMPORARY BREAKS AT MHK THIS MORNING. SOME DRY AIR IS APPROACHING
THE TAF SITES WITH LOW POTENTIAL FOR ADDITIONAL BREAKS TO VFR IN
THE NEXT FEW HOURS. FEEL MVFR WILL BE PREDOMINANT THIS AFTERNOON
THOUGH WITH A SLOW RISE TO AROUND 2700 FT BY LATE AFTERNOON.
MOISTURE INCREASES OVERNIGHT WITH CIGS DROPPING CLOSER TO 1000 FT
BEFORE SUNRISE WITH SOME POTENTIAL FOR IFR BY SUNRISE. ANTICIPATE
CIGS HOLDING ON THROUGH THE ENTIRE TAF.

BARJENBRUCH

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$








AREA FORECAST DISCUSSION

NWS WICHITA KS

 1132 AM CST WED FEB 8 2012

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

MAIN AVIATION CONCERN/CHALLENGE WILL BE TIMING DISSIPATION OF LOW
CLOUDS. SOME HINTS ON VISIBLE SATELLITE THAT THIS IS ALREADY
TRYING TO OCCUR OVER WESTERN PORTIONS OF KS AND OK.
ADDITIONALLY...NAM/GFS MODELS BOTH CLEAR CLOUDS OUT THIS
AFTERNOON. HOWEVER...THINKING THE MORE PESSIMISTIC RUC MODEL HAS
THE BEST FORECAST...HOLDING LOW MVFR CIGS ACROSS THE AREA WELL
INTO THIS EVENING. THIS MAKES SENSE GIVEN INCREASING UPPER LEVEL
CLOUDS ALONG WITH WEAK BOUNDARY LAYER FLOW. IN FACT...WOULDN`T BE
SURPRISED IF MVFR CIGS HANG TOUGH ALL NIGHT...DUE TO WARM
ADVECTION INCREASING AND STRENGTHENING THE INVERSION. FOR
NOW...WENT LOW MVFR THROUGH 00Z THIS EVENING...AND THEN RAISED
EVERYONE UP ABOVE 2000 FT AGL...ALTHOUGH CIGS COULD REMAIN BELOW
2000 FT ALL NIGHT.

ADK

&&

.PREV DISCUSSION... /ISSUED 553 AM CST WED FEB 8 2012/

AVIATION...12Z TAFS KRSL/KSLN/KHUT/KICT/KCNU

IFR AND MVFR CEILINGS WILL LINGER ACROSS THE AREA FOR A GOOD PORTION
OF THE DAY...AS LOW LEVEL MOISTURE REMAINS TRAPPED UNDER THE
SUBSIDENCE INVERSION FROM THE CANADIAN HIGH PRESSURE SETTLING ACROSS
THE PLAINS. NOT ALOT OF CONFIDENCE IN THIS STRATUS CLOUD DECK
CLEARING OUT UNTIL LATE THIS AFTERNOON...AS MAIN CLEARING WILL BE
EROSION OF THE CLOUDS BY BURNING IT OFF FROM THE SUNSHINE.  EVEN AS
THE CLOUDS REMAIN TODAY...SHOULD SEE A GENERAL IMPROVING/LIFTING OF
THE CEILINGS TO ALL MVFR.

NOT ALOT OF CONFIDENCE ON TIMING OF THE CLEARING OF THE STRATUS DECK
TOWARDS THE LAST PORTION OF THE TAF FORECAST...BUT WILL TRY TO CLEAR
OUT LOW CLOUDS AFTER 00Z/THU. LOWEST CONFIDENCE IN THIS CLEARING
WILL BE OVER CEN KS...WHERE STRATUS WILL CLEAR OUR THIS EVENING.

KETCHAM

PREV DISCUSSION... /ISSUED 322 AM CST WED FEB 8 2012/

DISCUSSION...

MAIN FORECAST CHALLENGES INCLUDE TEMPERATURES FOR THE REMAINDER OF
THIS WEEK AND THE PRECIPITATION CHANCES FOR THE WEEKEND AND EARLY NEXT
WEEK.

SYNOPSIS:
THE UPPER LEVEL WEATHER SYSTEM IS MOVING EASTWARD OUT OF THE CENTRAL
PLAINS THIS MORNING.  LOW STRATUS IS PRESENT ACROSS MUCH OF THE AREA
IN THE WAKE THE UPPER LEVEL SYSTEM.  THE BLANKET OF CLOUDS HAS KEPT
TEMPERATURES WARMER DESPITE THE INFLUX OF HIGH PRESSURE.

TODAY - FRIDAY:
HIGH PRESSURE WILL DOMINATE THROUGH THIS PERIOD.  SURFACE HIGH
PRESSURE IS BUILDING IN ACROSS KANSAS TODAY AND WILL SLIDE EASTWARD
OVERNIGHT.  THE LOW STRATUS THAT IS CURRENTLY IMPACTING THE AREA IS
EXPECTED TO PERSIST THROUGH MUCH OF THE DAY TODAY.  WHILE THIS HAS
KEPT OVERNIGHT TEMPERATURES WARMER THAN EXPECTED...THIS WILL KEEP
DAYTIME TEMPERATURES COOLER FOR TODAY.  EXPECT HIGHS IN THE 30S
ACROSS MUCH OF KANSAS.

THERE WILL BE A QUICK PERIOD OF RETURN FLOW AND BRIEF WARM UP FOR
THURSDAY BEFORE A SECOND MORE POTENT CANADIAN HIGH PRESSURE SURGES
INTO THE REGION.  THE NEXT COLD FRONT IS EXPECTED TO MOVE IN
THURSDAY NIGHT/EARLY FRIDAY WHICH WILL KNOCK TEMPERATURES BACK DOWN
BELOW NORMAL FOR FRIDAY.

BILLINGS

SATURDAY - TUESDAY:
ARCTIC AIRMASS STILL ON TRACK FOR THIS WEEKEND WITH A 1040MB SURFACE
HIGH PRESSURE MIGRATING SOUTH FROM CANADA.  CONTINUING TO TREND
TEMPS DOWN SLIGHTLY SINCE THE PREVIOUSLY WARMER GFS HAS SHOWN HINTS
OF BRINGING THE COLDER AIR FARTHER WEST IN LINE WITH THE NAM AND EC.

THE FIRST IN A SERIES OF SHORTWAVES APPROACHES FROM THE FOUR CORNERS
AREA LATE SUNDAY NIGHT INTO MONDAY.  WITH THE ARCTIC AIRMASS IN
PLACE PRECIPITATION SHOULD START AS ALL SNOW SUNDAY NIGHT...BUT AS THE
SURFACE HIGH PRESSURE MOVES EAST...SOUTHERLY FLOW WILL CAUSE
MID-LEVEL WARM ADVECTION AND WILL SUPPORT A CHANGEOVER TO A MIX OF
RAIN AND SNOW FOR MONDAY MORNING INTO THE EARLY AFTERNOON.

SECOND...AND SLIGHTLY MORE POTENT SHORTWAVE TROUGH FOLLOWS QUICKLY
ON THE HEELS OF THE FIRST...EJECTING INTO THE SOUTHERN PLAINS
TUESDAY EVENING.  LEE CYCLOGENESIS PULLS LOW TO MID 40 DEWPOINTS
INTO THE AREA ALONG WITH WARMER LOW AND MID LEVEL TEMPERATURES. THE EC
FORECAST SOUNDING IS SLIGHTLY COOLER THAN THE GFS...BUT HOVERS
AROUND FREEZING THROUGH THE LOW LEVELS...AND ALSO WARMS UP THROUGHOUT
THE PERIOD.  THE RESULT WOULD BE MAINLY RAIN FOR THE CWA WITH ANY
SNOWFLAKES MIXING IN CONFINED TO NORTHERN KANSAS.

ARL

FIRE WEATHER...
VERY LITTLE IN THE WAY OF FIRE WEATHER CONCERNS THROUGH THE FORECAST
WITH COOL AIR BEING THE MAIN THEME FOR THIS WEEK AND THE WEEKEND.
AFTER YESTERDAYS COLD FRONT ANOTHER MORE POTENT COLD FRONT WILL
SURGE IN ON THURSDAY NIGHT/FRIDAY.  WINDS WILL REMAIN LIGHT AND
RELATIVE HUMIDITIES HIGH.

BILLINGS

&&

.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT    36  23  49  24 /   0   0   0  10
HUTCHINSON      34  22  47  23 /   0   0   0   0
NEWTON          34  23  46  23 /   0   0   0   0
ELDORADO        36  22  48  24 /   0   0   0  10
WINFIELD-KWLD   38  23  49  27 /   0   0  10  10
RUSSELL         31  20  42  19 /   0   0   0   0
GREAT BEND      32  20  45  20 /   0   0  10  10
SALINA          33  21  46  21 /   0   0   0   0
MCPHERSON       33  22  46  22 /   0   0   0   0
COFFEYVILLE     40  23  49  30 /   0   0  10  10
CHANUTE         37  22  49  27 /   0   0   0   0
IOLA            37  22  48  27 /   0   0   0   0
PARSONS-KPPF    38  23  49  28 /   0   0   0  10

&&

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

&&

$$








AREA FORECAST DISCUSSION

NWS PITTSBURGH PA

 1236 PM EST WED FEB 8 2012

.SYNOPSIS...
AN UPPER LEVEL SYSTEM WILL BRING WIDESPREAD SNOW SHOWERS TO THE
AREA TODAY. HIGH PRESSURE WILL BRING SEASONABLE TEMPERATURES AND
DRY CONDITIONS ON THURSDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UL WAVE IS SWINGING THROUGH THE UPPER OHIO VALLEY, AHEAD OF THE
MAIN TROUGH. THIS WAVE WILL MOVE THROUGH VERY QUICKLY...ENDING THE
SNOW FROM WEST TO EAST LATE THIS AFTERNOON.

CONFIDENT THAT THE HIGHEST AMOUNTS OF SNOW WILL BE 2 TO 4 INCHES
ACROSS THE RIDGE TOPS. ADVISORY CONTINUES FOR THE RIDGE COUNTIES
THROUGH THIS EVENING.

ELSEWHERE, A GENERAL 1 TO 2 WILL COVER MOST PLACES. ACCUMULATIONS
WILL BE LIMITED BY THE SPEED AT WHICH THIS SYSTEM WILL MOVE
THROUGH AND THAT MOST SFC TEMPS WILL RISE SLIGHTLY ABOVE FREEZING
TODAY, WITH THE EXCEPTION OF THE RIDGE TOPS.

TEMPERATURES ARE BLEND OF THE LATEST RUN OF THE HRRR AND 12Z NAM.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
SNOW SHOWERS ARE EXPECTED OVER THE SOUTHEAST RIDGES THIS EVENING,
WITH AN ADDITIONAL ACCUMULATION AROUND AN INCH POSSIBLE.

DRY HIGH PRESSURE WILL THEN BRING NEAR NORMAL TEMPERATURES INTO
FRIDAY.

FOR FRIDAY, MODELS CONTINUE TO HAVE TIMING ISSUES WITH ARCTIC
FRONT APPROACHING. HAVE GONE MIDDLE OF THE ROAD WITH HIGH CHANCE
TO LIKELY POPS LATE IN THE AFTERNOON. EXPECT A RAIN AND SNOW MIX
IN THE FAR SOUTH WITH SNOW ELSEWHERE. WILL PROBABLY AGAIN HAVE TO
DEAL WITH LIGHT ACCUMULATIONS. BUT WITH THIS SYSTEM, IT APPEARS
THE HIGHER ACCUMULATIONS WILL BE ACROSS THE NORTH.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
LATEST ECMWF AND GFS MODEL RUNS CONTINUE TO SHOW A DEEP UPPER TROUGH
PLUNGING ACROSS EASTERN CANADA DURING THE WEEKEND. 00Z ECMWF
INDICATES A SURFACE WAVE DEVELOPING ALONG THE BOUNDARY WHICH WOULD
TEND TO SLOW DOWN EASTWARD PROGRESS FRIDAY NIGHT...AND WOULD
LENGTHEN DURATION OF PRECIPITATION INTO SATURDAY. REGARDLESS OF
TIMING...VERY COLD CYCLONIC FLOW BEHIND THE SYSTEM SHOULD MAINTAIN
SCATTERED SNOW SHOWERS OVER THE REGION THROUGH SATURDAY.

STRONG SURFACE HIGH IS PROGGED TO BUILD SOUTHEASTWARD INTO THE MS
VALLEY BY SUNDAY AND THEN SLIDE EAST TO THE ATLANTIC COAST BY
TUESDAY. TEMPERATURES ARE FORECAST TO CHILL DOWN TO BETWEEN 5 AND 10
DEGREES BELOW NORMAL OVER THE WEEKEND...AND THEN MODERATE TO A FEW
DEGREES ABOVE NORMAL IN RETURN FLOW BY TUESDAY.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
EXPECT GENERALLY IFR RESTRICTIONS TO CONTINUE WELL INTO THE
AFTERNOON AS SNOW ASSOCIATED WITH UPPER LEVEL SYSTEM MOVES ACROSS
THE TERMINALS. CONDITIONS SHOULD IMPROVE TO MVFR BY LATE AFTERNOON
AS STEADY SNOW TAPERS OFF TO SNOW SHOWERS BEFORE COMING TO AN END
IN ALL LOCATIONS THIS EVENING. CLEARING IS EXPECTED BY MIDNIGHT
THAT WILL FURTHER IMPROVE FLIGHT CONDITIONS TO VFR.

OUTLOOK...THURSDAY THROUGH SUNDAY...
BUILDING HIGH PRESSURE IN THE WAKE OF THE LOW PRESSURE SYSTEM
WILL PROVIDE VFR FOR THE END OF THE WORK WEEK. ANOTHER COLD FRONT
IS FORECAST TO SPAWN MORE SHSN FRIDAY NIGHT INTO SATURDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
     MDZ001.
OH...NONE.
PA...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
     PAZ074-076.
WV...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
     WVZ023-041.

&&

$$







AREA FORECAST DISCUSSION

NWS GLASGOW MT

 1005 AM MST WED FEB 8 2012

.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH FRIDAY...
LOW CLOUDS CONTINUE TO ERODE THIS MORNING...LINGERING IN THE
NORTHEAST AND WESTERN MOST ZONES. UPDATING FORECAST FOR CONTINUED
DIMINISHING CLOUD COVER TODAY. ALSO LOWERED TEMPERATURES SLIGHTLY
FOR THE NORTHEAST WITH CLOUDS EXPECTED TO LINGER LONGEST. EBERT

PREVIOUS SHORT TERM DISCUSSION...THE SHORT TERM OF THE FORECAST
STARTS OUT DIFFICULT WITH A SURFACE HIGH EXTENDING INTO EXTREME
NORTHEAST MONTANA...AND AN UPPER LOW OVERHEAD. A MASS OF STRATUS
CLOUDS RESIDES OVER MOST OF NORTHEAST MONTANA AND SOUTHERN
SASKATCHEWAN THIS MORNING. HRRR MODEL MOVES THE MASS MORE NORTH
INTO SASKATCHEWAN...HOWEVER DOES HOLD SOME BACK OVER THE
NORTHEASTERN ZONES THROUGH THE DAY. GOING TO TREND TOWARDS AGAIN
SOME CLEARING AS PER THE HRRR MODEL... BUT CONFIDENCE ISN/T 100
PERCENT THAT THE STRATUS WON/T LIFT OUT UNTIL THE LOW LEVEL
EASTERLY FLOW SHIFTS WEST THIS EVENING.

TONIGHT... FOR NOW WILL GO WITH THE PARTLY CLOUDY SKY COVER...
HOWEVER LOOKING AT LAYERED RH HAS SOME CONCERN THAT THE MASS OF
STRATUS OVER SASKATCHEWAN WILL PUSH SOUTH AGAIN. KEEPING THAT IN
MIND DID A SPLIT ON TEMPERATURES...IF THE AREA STAYS CLEAR THE
FORECAST WILL BUST TOO WARM. IF THE STRATUS DOES COME IN THEN THE
FORECAST WILL SIDE TOO COLD.

THURSDAY...COLD AIR SPILLS IN FROM CENTRAL CANADA AND FORMS A
BOUNDARY WITH THE PACIFIC AIR MASS OVER CENTRAL MONTANA. THIS
SHOULD KEEP ANY SNOW FALL OUTSIDE OF THE FORECAST AREA WITH THE
EXCEPTION OF THE FAR SOUTHWESTERN ZONES. SKY COVER WILL BE HARD TO
HANDLE DURING THIS PERIOD. STRONG SURFACE HIGH AND DRY AIR WILL
KEEP THE NORTHEASTERN ZONES CLEAR...BUT AS THE PACIFIC MODIFIED
AIR MASS CLIMBS THE DEEP ARCTIC AIR A DECK OF CLOUDS IN VICINITY
OF THE FRONT.

THIS TREND WILL CONTINUE THURSDAY NIGHT INTO FRIDAY WITH
RE-ENFORCING SHOTS OF COLD AIR OVER THE EASTERN ZONES FROM THE
UPPER LOW OVER HUDSON BAY.                PROTON


.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...
THE PERIOD STARTS OUT ON THE COLD SIDE WITH A CANADIAN HIGH
PRESSURE STILL INFLUENCING THE AREA FRI NIGHT/SAT. THE AMPLIFIED
PATTERN BREAKS DOWN...WITH THE WESTERN RIDGE WEAKENING AND MOVING
E. THIS ALLOWS SHORTWAVES TO START MOVING INLAND ACROSS THE WESTERN
STATES BEGINNING SUNDAY.

QUITE A FEW MODEL DIFFERENCES WITH THESE SHORTAVES...TIMING...INTENSITY...
AND DIRECTION OF MOVEMENT. 00Z GFS QUITE DIFFERENT WITH A WEAKER
TUE SYSTEM...ENERGY ABSORBED BY A QUICKLY FOLLOWING WED SYSTEM.

THERE IS SIGNIFICANT WEAKENING OF THE UPPER FLOW OVER THE WESTERN
STATES...MAKING SPLITTING OF ENERGY LIKELY WITH THESE SYSTEMS. NONE OF
THESE SHORTWAVES ARE VERY STRONG EITHER. JUST ENOUGH MODEL
CONSENSUS TO EXPECT THE FIRST SHORTWAVE SUNDAY TO BE WEAKER THAN
THE 2ND SYSTEM TUE/TUE NIGHT. WILL MAINTAIN JUST A LITTLE HIGHER
POP FOR THESE. EXPECT PRECIP TYPE AS MAINLY LIGHT SNOW...ALTHOUGH
HIGHS LIKELY TO BE A LITTLE ABOVE FREEZING TUE. SIMONSEN

&&

.AVIATION...
LIMITED CLEARING SKIES...BRINGING VFR CONDITIONS...HAVE FINALLY
RETURNED TO ALL TAF SITES IN NORTHEAST MONTANA WITH LINGERING IFR
CONDITIONS ONLY VERY RECENTLY CLEARING AWAY TOWARD THE NORTHEAST
FROM KSDY. GUSTIER NORTHWEST WINDS WILL SET UP ON THURSDAY AS MVFR
CONDITIONS IN THE FORM OF SOME LOW LEVEL CLOUDS MAY SNEAK IN
TOWARD THE END OF THIS TAF CYCLE. BMICKELSON

&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

WEATHER.GOV/GLASGOW






AREA FORECAST DISCUSSION

NWS OMAHA/VALLEY NE

 1247 PM CST WED FEB 8 2012

.AVIATION...
18Z TAFS FOR KOFK...KLNK AND KOMA.

STLT IMAGERY AND OBS SHOW AN AREA OF MVFR CIGS WEST OF KOFK AND
OVER KLNK...KOMA. THE CIGS WILL BE VARIABLE AS A LOOP SHOW SOME
DISSIPATING CLOUDS TRYING TO MOVE TOWARD KLNK FM THE
NORTH...ALTHOUGH CLDS HAD SCATTERED OUT A KOMA...HAVE REDEVELOPED.
RH PROGS DO NOT HAVE A HANDLE ON THESE AS SOME ARE DRIER IN THE
LOW LEVELS AND OTHERS SATURATED. OVERALL WILL CONTINUE TO MENTION
MVFR OR VARIABLE MVFR CIGS THIS AFTERNOON...BECOMING PREDOMINANT
AT ALL THREE SITES AND CONTINUING OVERNIGHT. SOME MVFR VSBYS ARE
EXPECTED AS WELL. WEST OR SOUTHWEST WINDS ARE 5 TO 10KTS AT
KOFK...AND LIGHT AND VARIABLE AT KOMA AND KLNK. WINDS SHOULD BE
LIGHT...THEN INCREASE OUT OF THE SOUTHWEST THURSDAY MORNING. WITH
THE INCREASING WINDS EXPECT THE LOW CLOUDS TO IMPROVE FROM MID
MORNING ON.

&&

.PREV DISCUSSION... /ISSUED 508 AM CST WED FEB 8 2012/

AVIATION...
12Z TAFS FOR KOFK...KLNK AND KOMA.

MVFR CIGS NEAR FL025 WILL CLEAR THE KOFK AREA EARLY...HOWEVER CIGS
BETWEEN FL025 AND FL035 WILL REMAIN OVER KLNK AND KOMA THROUGH THE
DAY. AS WINDS TURN TO THE SOUTHWEST LATE IN THE DAY...MVFR CIGS
BELOW FL020 SHOULD RETURN TO ALL TAF SITES...GENERALLY AROUND 00Z.
A GRADUAL LOWERING OF CIGS TO BELOW FL010 IS EXPECTED BY 06Z WITH
AREAS OF 5SM FOG.

DERGAN

PREV DISCUSSION... /ISSUED 316 AM CST WED FEB 8 2012/

DISCUSSION...

SFC HIGH PRESSURE CONTINUES TO MOVE SOUTH OVER THE FORECAST AREA
THIS MORNING WHILE LOW CLOUDS LINGER OVERHEAD. DIFFICULT TO GET A
GOOD HANDLE ON HOW QUICKLY/SLOWLY THE STRATUS DECK WILL ERODE. SOME
CLEARING HAS TAKEN PLACE OVER THE NORTHERN CWA AND ACROSS THE
MISSOURI RIVER VALLEY...HOWEVER THIS HAS BEEN A GENERALLY SLOW
PROCESS THIS MORNING. LATEST RUC AND HRRR MODEL RUNS SHOW SLOW SOUTHWARD
CLEARING SO WL KEEP MOSTLY CLOUDY GOING IN THE SOUTH WITH PARTLY
CLOUDY IN OUR NORTH FOR THE FIRST HALF OF THE DAY. IN THE UPPER
LEVELS...A PIECE OF ENERGY OVER EASTERN MONTANA WILL CONTINUE TO
MOVE SOUTHEAST TOWARD THE FORECAST AREA BY TONIGHT. FORCING
REMAINS VERY WEAK AND MOISTURE IS LIMITED SO NO MENTION OF
FLURRIES OR LIGHT SNOW WITH THE PASSAGE OF THIS WAVE.

WEAK WARM AIR ADVECTION SETS UP ON THURSDAY IN RETURN FLOW
REGIME...PROVIDING A BRIEF WARM UP INTO THE LOWER TO MID 30S. A
STRONG PUSH OF COLD AIR WILL SPREAD SOUTH ACROSS THE NRN PLAINS AND
INTO THE MIDWEST BY THURSDAY NIGHT IN ASSOCIATION WILL UPPER
TROF DIGGING ACROSS EASTERN CANADA. THE COLDER TEMPS WL CONTINUE
THROUGH THE WEEKEND WITH THE COLDEST OF THE DAYS ON SATURDAY. HIGHS
OVER THE SNOW COVER WILL LIKELY STRUGGLE TO WARM ABOVE THE UPPER
TEENS.

SFC HIGH PRESSURE BUILDS OVER THE CWA ONCE AGAIN ON SUNDAY WITH
STRONG WARM AIR ADVECTION RETURNING SUNDAY NIGHT. MEDIUM RANGE
MODELS IN GOOD AGREEMENT ON MOVING A SHORTWAVE TROF THRU THE FOUR
CORNERS REGION SUNDAY NIGHT AND INTO THE CENTRAL PLAINS BY MONDAY
MORNING. FORCING AHEAD OF THIS WAVE SHOULD ALLOW SNOW TO DEVELOP
SUNDAY NIGHT INTO MONDAY ACROSS MUCH OF THE SOUTHERN FORECAST
AREA.

YET ANOTHER WAVE IS PROGGED TO MOVE INTO THE CNTRL PLAINS FOR MID
WEEK. MODELS KEEP GETTING A BIT STRONGER WITH THIS SYSTEM AND
CONTINUE TO CLOSE IT OFF AS IT MOVES INTO THE CNTRL PLAINS.

KERN

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&

$$

ZAPOTOCNY




AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

 550 PM EST WED FEB 8 2012

.SYNOPSIS...
A STRONG UPPER LEVEL SYSTEM CROSSING THE MID-ATLANTIC REGION THIS
AFTERNOON WILL MOVE OFFSHORE LATE TONIGHT INTO EARLY THURSDAY.
HIGH PRESSURE OVER THE MID MISSISSIPPI VALLEY WILL SLIDE EAST TO
THE CAROLINA COAST THROUGH FRIDAY...PROVIDING FAIR AND DRY
WEATHER IN PENNSYLVANIA FOR THE END OF THE WEEK. AN AMPLIFYING
UPPER LEVEL TROUGH OVER THE EASTERN U.S. WILL SEND A STRONG COLD
FRONT SOUTHEAST ACROSS THE STATE FRIDAY NIGHT...ALLOWING MODIFIED
ARCTIC AIR TO POUR INTO THE REGION FOR THE WEEKEND.

&&

.NEAR TERM /UNTIL 10 PM THIS EVENING/...
EVENING WV LOOP SHOWS THE MID LVL SHORTWAVE RESPONSIBLE FOR THE
LGT SNFL PIVOTING EWD INTO SOUTHWEST PA. THE BEST AREA OF
ENHANCED LIFT VIA LEFT EXIT REGION UPPER JET DYNAMICS APPEARS TO
BE SHIFTING EAST OF PA IN VICINITY OF DEVELOPING COASTAL LOW. OVER
THE LAST COUPLE OF HOURS RADAR RETURNS HAVE BECOME MARKEDLY
LIGHTER ACROSS CENTRAL PA. 22Z RUC ANALYSIS SHOWS AN INVERTED SFC
TROUGH EXTENDING NWD ALONG THE ALLEGHENIES FROM A DEVELOPING 1014MB
LOW E OF CAPE HATTERAS. MDL QPF/S ARE IN GOOD AGREEMENT WITH AN
ADDITIONAL 0.05 INCHES OR SO ACROSS THE LOWER SUSQ VALLEY AND
EVEN LIGHTER AMTS FURTHER WEST. WITH SNOW/WATER RATIOS ARND
13/1...THIS WILL TRANSLATE TO ADDITIONAL ACCUMS UP TO AN INCH OVR
THE SE ZONES. THE LAST OF THE LGT SNOW SHOULD BE OVER BY
MIDNIGHT...AS LG SCALE SUBSIDENCE OVERSPREADS THE REGION IN WAKE
OF DEPARTING MID LVL SHORTWAVE.

WEBCAMS INDICATE THAT SNOW HAS ACCUMULATED MAINLY ON THE GRASSY
SFCS...AS ROAD TEMPERATURES/TIME OF DAY HAVE BEEN LIMITING
FACTORS. A WINTER WEATHER ADVISORY REMAINS IN EFFECT FOR THE
LAUREL HIGHLANDS AND S-CENTRAL MTNS WITH STORM TOTALS BETWEEN 2-4
INCHES...WITH THE HIGHEST AMTS ON THE RIDGES WEST OF RT 219. PHL
ISSUED AN IMPACT-BASED ADVISORY /1-2" FOR THE EVE COMMUTE/ AND LWX
HAS LOWER ADVY CRITERIA. THIS EXPLAINS THE GAP IN THE HEADLINES
BETWEEN THE NEIGHBORING OFFICES. BASED ON LATEST RADAR
TRENDS...WILL LIKELY BE ABLE TO CANCEL OUR WW ADVISORY BEFORE THE 10
PM EXPIRATION.

TEMPERATURES WILL CONTINUE TO HOLD STEADY IN THE UPPER 20S AND LOW
30S THROUGH THE EVE BEFORE GRADUALLY DROPPING OFF INTO THE LOW TO
MID 20S OVERNIGHT.

&&

.SHORT TERM /10 PM THIS EVENING THROUGH 6 PM THURSDAY/...
SHALLOW BKN-OVC CLOUD COVER...A 5-10 KT NW SFC WIND AND JUST A FEW
MTN FLURRIES WILL LINGER INTO LATE TONIGHT. ALL SNOW SHOULD END BY
MIDNIGHT...WITH GRADUAL CLEARING FROM NW TO SE INTO THE EARLY
MORNING HOURS ON THURS. MIN TEMPS AT DAYBREAK THURSDAY WILL BE IN
THE UPPER TEENS ACROSS THE HIGHER TERRAIN OF THE NORTH AND
WEST...AND LOWER TO MID 20S IN THE CENTRAL AND SE ZONES.

HIGH PRESSURE SLIDES INTO THE REGION FROM THE MID MS VLY.
INCREASING WESTERLY FLOW AND WARMING ALOFT WILL ALLOW TEMPS TO
REBOUND BACK TO ABOVE NORMAL MAXS BY SEVERAL DEG F OR MORE. CLOUD
COVER LOOKS TO BE QUITE MINIMAL UNDER STRONG ANTICYCLONIC LOW-
MID LEVEL FLOW. HIGHS WILL BE IN THE MID 30S ACROSS THE MTNS...AND
UPPER 30S TO LOWER 40S ELSEWHERE.

&&

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
NEXT COLD FRONT EVEN SLOWER NOW. ADJUSTED FCST SOME FOR THIS.

FIRST PUSH OF COLDER AIR MOVES INTO THE AREA LATE FRIDAY NIGHT.

SECOND PUSH OF COLD AIR MOVES IN ON SUNDAY.

MODELS TODAY SHOW MORE DIRECTIONAL SHEAR. STILL EXPECT SOME
LAKE EFFECT LATE FRIDAY NIGHT INTO SUNDAY NIGHT WITH THE
COLD AIR ACROSS THE LAKES...BUT THINK INLAND EXTENT WILL
BE LIMITED...AND ALSO AMTS SHOULD NOT BE ALL THAT GREAT...
GIVEN THE ABOVE FACTOR.

IT WILL BE WINDY OVER THE WEEKEND...THUS THERE WILL BE SOME
WIND CHILL WITH THIS AIRMASS...A CHANGE FROM RECENT WEEKS.

DID EDGE TEMPS DOWN SOME THROUGH MONDAY...BUT DID NOT WANT
TO JUMP ON THE COLD AIR TOO HARD. STILL A LOT OF SPREAD
IN MODEL SOLUTIONS.

LEFT THE FCST DRY AFTER SUNDAY NIGHT...A LOT OF MODEL
SPREAD AND ALSO HPC HAS DECENT SW FLOW INTO WED. JUST
HARD TO SEE A REASON TO INTRODUCE RAIN AND SNOW AT THIS
POINT.

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
WDSPRD IFR/LIFR CONDS WILL CONTINUE THRU EARLY EVE IN LGT TO MOD
SN WITH VIS BTWN 1/2-2SM. VIS WILL GREATLY IMPROVE AS THE SNOW
ENDS BUT LOW CIGS MAY PERSIST MAINLY OVR THE MTNS. ALL GUIDANCE
RETURNS VFR FLYING INTO EARLY THURS MORNING...WITH GOOD FLYING
PERSISTING THRU THE END OF THE WEEK.

OUTLOOK...
THU-FRI...VFR.
FRI NIGHT-SUN...RESTRICTIONS LKLY.
MON...VFR.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ024>026-033>035.

&&

$$
SYNOPSIS...STEINBUGL
NEAR TERM...FITZGERALD/STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...MARTIN
AVIATION...STEINBUGL







AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

 353 PM EST WED FEB 8 2012

.SYNOPSIS...
A STRONG UPPER LEVEL SYSTEM CROSSING THE MID-ATLANTIC REGION THIS
AFTERNOON WILL MOVE OFFSHORE LATE TONIGHT INTO EARLY THURSDAY.
HIGH PRESSURE OVER THE MID MISSISSIPPI VALLEY WILL SLIDE EAST TO
THE CAROLINA COAST THROUGH FRIDAY...PROVIDING FAIR AND DRY
WEATHER IN PENNSYLVANIA FOR THE END OF THE WEEK. AN AMPLIFYING
UPPER LEVEL TROUGH OVER THE EASTERN U.S. WILL SEND A STRONG COLD
FRONT SOUTHEAST ACROSS THE STATE FRIDAY NIGHT...ALLOWING MODIFIED
ARCTIC AIR TO POUR INTO THE REGION FOR THE WEEKEND.

&&

.NEAR TERM /UNTIL 10 PM THIS EVENING/...
AFTN WV LOOP SHOWS THE MID LVL SHORTWAVE RESPONSIBLE FOR THE
LGT SNFL PIVOTING EWD ACRS THE CENTRAL APPALACHIANS. THE BEST
AREA OF ENHANCED LIFT VIA LEFT EXIT REGION UPPER JET DYNAMICS
APPEARS TO BE SHIFTING SEWD TOWARD THE DC AREA PER RECENT RADAR
RETURNS...WITH GENERALLY LIGHTER/FINER DEFORMATION TYPE SNOWS
WRAPPING EWD ACRS WRN AND CNTRL PA. 19Z RUC ANALYSIS SHOWS AN
INVERTED SFC TROUGH EXTENDING NWD ALONG THE ALLEGHENIES FROM A
WEAK 1021MB LOW OVER THE WV PNHDL. MDL QPF/S ARE IN GOOD AGREEMENT
WITH AN ADDITIONAL 0.10-0.25" LIQ EQUIVS INVOF SOUTH MTN AND THE
LWR SUSQ VLY THRU 0000 UTC. ADDITIONAL ACCUMS OF 0.5-1.0 CAN BE
EXPECTED THROUGH THE LATE EVE.

WEBCAMS INDICATE THAT SNOW IS ACCUMULATING MAINLY ON THE GRASSY
SFCS...AS ROAD TEMPERATURES/TIME OF DAY CONTINUE TO BE LIMITING
FACTORS. A WINTER WEATHER ADVISORY REMAINS IN EFFECT FOR THE
LAUREL HIGHLANDS AND S-CENTRAL MTNS WITH STORM TOTALS BETWEEN 2-4
INCHES...WITH THE HIGHEST AMTS ON THE RIDGES WEST OF RT 219. PHL
ISSUED AN IMPACT-BASED ADVISORY /1-2" FOR THE EVE COMMUTE/ AND LWX
HAS LOWER ADVY CRITERIA. THIS EXPLAINS THE GAP IN THE HEADLINES
BETWEEN THE NEIGHBORING OFFICES.

TEMPERATURES WILL CONTINUE TO HOLD STEADY IN THE UPPER 20S AND LOW
30S THROUGH THE EVE BEFORE GRADUALLY DROPPING OFF INTO THE LOW TO
MID 20S OVERNIGHT. SNOWFALL TAPERS OFF FROM WEST TO EAST THIS
EVENING AND EARLY TNT...AS THE MID-UPPER TROUGH /AND MEAGER SFC
WAVE/ SLIDES OFF THE MID ATLANTIC/VA COAST.

&&

.SHORT TERM /10 PM THIS EVENING THROUGH 6 PM THURSDAY/...
SHALLOW BKN-OVC CLOUD COVER...A 5-10 KT NW SFC WIND AND JUST A FEW
MTN FLURRIES WILL LINGER INTO LATE TONIGHT. ALL SNOW SHOULD END BY
MIDNIGHT...WITH GRADUAL CLEARING FROM NW TO SE INTO THE EARLY
MORNING HOURS ON THURS. MIN TEMPS AT DAYBREAK THURSDAY WILL BE IN
THE UPPER TEENS ACROSS THE HIGHER TERRAIN OF THE NORTH AND
WEST...AND LOWER TO MID 20S IN THE CENTRAL AND SE ZONES.

HIGH PRESSURE SLIDES INTO THE REGION FROM THE MID MS VLY.
INCREASING WESTERLY FLOW AND WARMING ALOFT WILL ALLOW TEMPS TO
REBOUND BACK TO ABOVE NORMAL MAXS BY SEVERAL DEG F OR MORE. CLOUD
COVER LOOKS TO BE QUITE MINIMAL UNDER STRONG ANTICYCLONIC LOW-
MID LEVEL FLOW. HIGHS WILL BE IN THE MID 30S ACROSS THE MTNS...AND
UPPER 30S TO LOWER 40S ELSEWHERE.

&&

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
NEXT COLD FRONT EVEN SLOWER NOW. ADJUSTED FCST SOME FOR THIS.

FIRST PUSH OF COLDER AIR MOVES INTO THE AREA LATE FRIDAY NIGHT.

SECOND PUSH OF COLD AIR MOVES IN ON SUNDAY.

MODELS TODAY SHOW MORE DIRECTIONAL SHEAR. STILL EXPECT SOME
LAKE EFFECT LATE FRIDAY NIGHT INTO SUNDAY NIGHT WITH THE
COLD AIR ACROSS THE LAKES...BUT THINK INLAND EXTENT WILL
BE LIMITED...AND ALSO AMTS SHOULD NOT BE ALL THAT GREAT...
GIVEN THE ABOVE FACTOR.

IT WILL BE WINDY OVER THE WEEKEND...THUS THERE WILL BE SOME
WIND CHILL WITH THIS AIRMASS...A CHANGE FROM RECENT WEEKS.

DID EDGE TEMPS DOWN SOME THROUGH MONDAY...BUT DID NOT WANT
TO JUMP ON THE COLD AIR TOO HARD. STILL A LOT OF SPREAD
IN MODEL SOLUTIONS.

LEFT THE FCST DRY AFTER SUNDAY NIGHT...A LOT OF MODEL
SPREAD AND ALSO HPC HAS DECENT SW FLOW INTO WED. JUST
HARD TO SEE A REASON TO INTRODUCE RAIN AND SNOW AT THIS
POINT.

&&

.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
WDSPRD IFR/LIFR CONDS WILL CONTINUE THRU EARLY EVE IN LGT TO MOD
SN WITH VIS BTWN 1/2-2SM. VIS WILL GREATLY IMPROVE AS THE SNOW
ENDS BUT LOW CIGS MAY PERSIST MAINLY OVR THE MTNS. ALL GUIDANCE
RETURNS VFR FLYING INTO EARLY THURS MORNING...WITH GOOD FLYING
PERSISTING THRU THE END OF THE WEEK.

OUTLOOK...
THU-FRI...VFR.
FRI NIGHT-SUN...RESTRICTIONS LKLY.
MON...VFR.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ024>026-033>035.

&&

$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...MARTIN
AVIATION...STEINBUGL







AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

 304 PM EST WED FEB 8 2012

.SYNOPSIS...
A STRONG UPPER LEVEL SYSTEM CROSSING THE MID-ATLANTIC REGION THIS
AFTERNOON WILL MOVE OFFSHORE LATE TONIGHT INTO EARLY THURSDAY.
HIGH PRESSURE OVER THE MID MISSISSIPPI VALLEY WILL SLIDE EAST TO
THE CAROLINA COAST THROUGH FRIDAY...PROVIDING FAIR AND DRY
WEATHER IN PENNSYLVANIA FOR THE END OF THE WEEK. AN AMPLIFYING
UPPER LEVEL TROUGH OVER THE EASTERN U.S. WILL SEND A STRONG COLD
FRONT SOUTHEAST ACROSS THE STATE FRIDAY NIGHT...ALLOWING MODIFIED
ARCTIC AIR TO POUR INTO THE REGION FOR THE WEEKEND.

&&

.NEAR TERM /UNTIL 10 PM THIS EVENING/...
AFTN WV LOOP SHOWS THE MID LVL SHORTWAVE RESPONSIBLE FOR THE
LGT SNFL PIVOTING EWD ACRS THE CENTRAL APPALACHIANS. THE BEST
AREA OF ENHANCED LIFT VIA LEFT EXIT REGION UPPER JET DYNAMICS
APPEARS TO BE SHIFTING SEWD TOWARD THE DC AREA PER RECENT RADAR
RETURNS...WITH GENERALLY LIGHTER/FINER DEFORMATION TYPE SNOWS
WRAPPING EWD ACRS WRN AND CNTRL PA. 19Z RUC ANALYSIS SHOWS AN
INVERTED SFC TROUGH EXTENDING NWD ALONG THE ALLEGHENIES FROM A
WEAK 1021MB LOW OVER THE WV PNHDL. MDL QPF/S ARE IN GOOD AGREEMENT
WITH AN ADDITIONAL 0.10-0.25" LIQ EQUIVS INVOF SOUTH MTN AND THE
LWR SUSQ VLY THRU 0000 UTC. ADDITIONAL ACCUMS OF 0.5-1.0 CAN BE
EXPECTED THROUGH THE LATE EVE.

WEBCAMS INDICATE THAT SNOW IS ACCUMULATING MAINLY ON THE GRASSY
SFCS...AS ROAD TEMPERATURES/TIME OF DAY CONTINUE TO BE LIMITING
FACTORS. A WINTER WEATHER ADVISORY REMAINS IN EFFECT FOR THE
LAUREL HIGHLANDS AND S-CENTRAL MTNS WITH STORM TOTALS BETWEEN 2-4
INCHES...WITH THE HIGHEST AMTS ON THE RIDGES WEST OF RT 219. PHL
ISSUED AN IMPACT-BASED ADVISORY /1-2" FOR THE EVE COMMUTE/ AND LWX
HAS LOWER ADVY CRITERIA. THIS EXPLAINS THE GAP IN THE HEADLINES
BETWEEN THE NEIGHBORING OFFICES.

TEMPERATURES WILL CONTINUE TO HOLD STEADY IN THE UPPER 20S AND LOW
30S THROUGH THE EVE BEFORE GRADUALLY DROPPING OFF INTO THE LOW TO
MID 20S OVERNIGHT. SNOWFALL TAPERS OFF FROM WEST TO EAST THIS
EVENING AND EARLY TNT...AS THE MID-UPPER TROUGH /AND MEAGER SFC
WAVE/ SLIDES OFF THE MID ATLANTIC/VA COAST.

&&

.SHORT TERM /10 PM THIS EVENING THROUGH 6 AM THURSDAY/...
SHALLOW BKN-OVC CLOUD COVER...A 5-10 KT NW SFC WIND AND JUST A FEW
MTN FLURRIES WILL LINGER INTO LATE TONIGHT. ALL SNOW SHOULD END BY
MIDNIGHT...WITH GRADUAL CLEARING FROM NW TO SE INTO THE EARLY
MORNING HOURS ON THURS. MIN TEMPS AT DAYBREAK THURSDAY WILL BE IN
THE UPPER TEENS ACROSS THE HIGHER TERRAIN OF THE NORTH AND
WEST...AND LOWER TO MID 20S IN THE CENTRAL AND SE ZONES.

HIGH PRESSURE SLIDES INTO THE REGION FROM THE MID MS VLY.
INCREASING WESTERLY FLOW AND WARMING ALOFT WILL ALLOW TEMPS TO
REBOUND BACK TO ABOVE NORMAL MAXS BY SEVERAL DEG F OR MORE. CLOUD
COVER LOOKS TO BE QUITE MINIMAL UNDER STRONG ANTICYCLONIC LOW-
MID LEVEL FLOW. HIGHS WILL BE IN THE MID 30S ACROSS THE MTNS...AND
UPPER 30S TO LOWER 40S ELSEWHERE.

&&

.LONG TERM /THURSDAY THROUGH WEDNESDAY/...
FRIDAY MORNING WILL START OUR CLEAR TO PARTLY CLOUDY ACROSS THE
EAST...WHILE A SHIELD OF LAYERED CLOUDS QUICKLY OVERSPREADS THE WEST
IN THE MODERATELY STRONG WARM ADVECTION PATTERN AHEAD OF AN ARCTIC
FRONT.

THIS FRONT WILL CROSS THE REGION FRIDAY NIGHT...BRINGING WITH IT
NUMEROUS SNOW SHOWERS AND POSSIBLE SQUALLS ACROSS THE WESTERN AND
NRN HIGH TERRAIN...WITH SCATTERED SNOW SHOWERS AND PERHAPS A BRIEF
SQUALL OVER THE CENTRAL AND EASTERN PARTS OF THE STATE.

TEMPS FRIDAY MAY BE A FEW DEG LOWER THAN THURSDAY ACROSS THE WESTERN
ZONES...WHILE THE EXTENT OF MORNING SUNSHINE IN THE CENTRAL AND EAST
/COMBINED WITH THE INCREASING AND WARMING DOWNSLOPE WESTERLY FLOW/
WILL ALLOW TEMPS TO WARM BY ANOTHER FEW DEG F...TOPPING OUT 4-7 DEG
F ABOVE NORMAL..

THE CORE OF THE REAL COLD AIR WILL STAY WELL TO THE NORTH OF LAKES
ERIE/ONTARIO...AND OVER EASTERN CANADA...WHERE THERE IS DECENT SNOW
COVER.

INCREASING LLVL...DIRECTIONAL SHEAR FROM THE WEST-NW WILL COMBINE
WITH RELATIVELY LOW SUBSIDENCE INVERSION HEIGHTS TO KEEP ANY MTN
SNOW SHOWERS ON THE MINIMAL SIDE SATURDAY INTO SUNDAY.

THE HIGH PRESSURE AREA WILL SETTLE TO THE SOUTH OF PENNSYLVANIA
EARLY NEXT WEEK...ALLOWING FOR A QUICK WARMUP AND DRY WEATHER MONDAY
AND TUESDAY.

&&

.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
WDSPRD IFR/LIFR CONDS WILL CONTINUE THRU EARLY EVE IN LGT TO MOD
SN WITH VIS BTWN 1/2-2SM. VIS WILL GREATLY IMPROVE AS THE SNOW
ENDS BUT LOW CIGS MAY PERSIST MAINLY OVR THE MTNS. ALL GUIDANCE
RETURNS VFR FLYING INTO EARLY THURS MORNING...WITH GOOD FLYING
PERSISTING THRU THE END OF THE WEEK.

OUTLOOK...
THU-FRI...VFR.
FRI NIGHT-SUN...RESTRICTIONS LKLY.
MON...VFR.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ024>026-033>035.

&&

$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...LAMBERT/MARTIN
AVIATION...STEINBUGL







AREA FORECAST DISCUSSION

NWS HOUSTON/GALVESTON TX

 1028 AM CST WED FEB 8 2012

.UPDATE...
RELATIVELY QUIET WEATHER ON TAP FOR SOUTHEAST TEXAS TODAY WITH
SURFACE HIGH PRESSURE BUILDING IN FROM THE NORTH. SKIES WILL
REMAIN PARTLY CLOUDY AS SOUTHWESTERLY FLOW ALOFT BRINGS HIGH
CLOUDS ACROSS THE REGION. CURRENT FORECAST IS IN GOOD SHAPE AND NO
CHANGES PLANNED FOR THIS MORNING. 38

&&

.MARINE...
WINDS OVER THE FAR OFFSHORE WATER RUNNING AROUND 20 KNOTS AND SEAS
OF 6 TO 7 FEET SHOULD BE VERY SLOW TO COME DOWN WITH THE NE FETCH.
SCA WILL COME DOWN THERE AT 3 PM BUT SCEC WILL LIKELY CONTINUE AFTER
THROUGH AT LEAST MID EVENING AND MAY GO PAST MIDNIGHT.

45

&&

.AVIATION...
BACK TO VFR. HIGH CLOUDS AND NORTH WINDS 5-13KTS DIMINISHING
OVERNIGHT.

45

&&

.PREV DISCUSSION... /ISSUED 417 AM CST WED FEB 8 2012/

DISCUSSION...
A WEAK NORTHERN BOUNDARY SLIPPING ACROSS THE AREA EARLY THIS
MORNING...ONLY NOTICEABLE IN THE INCREASED PRESSURE FIELD AND
IN THE REINFORCING OF THE ANCHORED COOL AND DRY AIR MASS. A DAY
OF SCATTERED MID TO HIGH CLOUD COVER WITH THIS SLIGHTLY COOLER
NORTHERLY AIR MASS ONLY NOTICEABLE IN THE MAXIMUM TEMPERATURE
NUMBERS...A FEW DEGREES COOLER THAN YESTERDAY.

THE SYNOPTIC SCENARIO OF A MID TO LATE WEEK WEST COAST UPPER LOW
CUTTING OFF AND SETTLING IN OVER BAJA IS STILL ON TRACK...WITH
INCREASING PRECIPITATION CHANCES FROM LATE THURSDAY ON INTO THE
WEEKEND. CHANCE PROBABILITIES APPEAR TO BE ON THE RISE FRIDAY
INTO SATURDAY BECAUSE OF A FEW FACTORS. FIRST WOULD BE A SERIES OF
SHORTWAVE DISTURBANCES WITHIN THE SOUTHWEST-TO-NORTHEAST FLOW
RIDING UP THE COAST AND PROVIDING ENOUGH INSTABILITY...IN TANDEM
WITH DECENT ISENTROPIC UPLIFT...TO PRODUCE MAINLY LIGHT RAIN AND
ELEVATED THUNDER. ANOTHER POSITIVE WILL BE THE POSITIONING OF THE
SOUTHERN BRANCH OF THE POLAR JET STREAM...WITH COASTAL TEXAS
FALLING UNDER THE LF QUADRANT EARLY FRIDAY THEN TRANSITIONING TO
BEING UNDER THE RR QUAD LATTER IN THE DAY. THUS...WARM AIR
ADVECTION-TYPE LIGHT RAIN (LOW QPF) AS LOWER LEVEL DRY AIR (PER
ENTRENCHED LL (NORTH)EASTERLY FLOW) SHOULD COUNTERACT ANY
SIGNIFICANT ACCUMULATION/WIDESPREAD MODERATE RAIN COVERAGE.

SHALLOW UPPER LEVEL TROUGH AXIS WILL MOVE TO THE EAST OF TEXAS BY
SATURDAY AFTERNOON WITH ANOTHER WESTERN TROUGH EVOLVING OVER THE
ROCKIES SUNDAY INTO MONDAY. LEE SURFACE PRESSURES BEGIN TO LOWER
ACROSS WESTERN TEXAS EARLY MONDAY...ALLOWING MID-LOW WINDS TO TURN
AROUND TO ONSHORE AND BEGIN AN EARLY WEEK MOISTURE PUMP. INCREASING
HUMIDITIES AND RAIN CHANCES AS THE AREA FALLS JUST DOWNSTREAM OF A
DEVELOPING TEXAS PANHANDLE COLD FRONT. A PRIMARILY WEAK 5H TROUGH
PASSAGE MONDAY IS MODELED TO BE FOLLOWED BY A MUCH STRONGER STORM
SYSTEM TIMED TO AFFECT THE REGION A WEEK FROM NOW. THUS...MODEST
RAIN CHANCES FROM MONDAY`S WEAKER SYSTEM ARE FORECAST TO PICK UP
AGAIN WEDNESDAY. THE MAIN COLD FRONT IS TIMED TO PASS ACROSS TEXAS
WEDNESDAY BUT...IN THE DAYS LEADING UP TO THIS FROPA...EXPECT A COUPLE
OF WARM (LOWER 70 MAX TEMPS/LOWS IN THE 50S) AND MORE HUMID COUPLE
OF DAYS UNDER MAINLY OVERCAST SKIES AND HIGHER RAIN CHANCES. 31

MARINE...
PRES GRADIENT TIGHTENING OFFSHORE AND BELIEVE CURRENT FLAG CONFIGURATION
LOOKS GOOD (CAUTION BAYS & NEARSHORE, ADVISORY OFFSHORE) THROUGH
THIS AFTERNOON. WINDS WILL DIMINISH A BIT AND BECOME MORE NE LATE
IN THE DAY AND TONIGHT...BUT REMAIN AROUND 15 KT OFFSHORE FOR SEVERAL
DAYS. ANOTHER FRONT WILL DROP INTO THE PLAINS AND ERN U.S. THIS
WEEKEND WHICH WILL AGAIN TIGHTEN THE GRADIENT ALONG THE UPPER TX
COASTAL WATERS. CORRESPONDING WINDS & SEAS WILL INCREASE. TIDE
LEVELS WILL PROBABLY RUN 1-1.5 FEET ABOVE NORMAL THIS WEEKEND INTO
EARLY NEXT WEEK WITH A DECENT FETCH OF ENE WINDS IN PLACE. 47

AVIATION...
VFR.  47

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      61  41  64  46  63 /  10  10  20  30  30
HOUSTON (IAH)              64  42  65  45  65 /  10  10  20  20  30
GALVESTON (GLS)            62  50  62  51  64 /  10  10  20  20  30

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 3 PM CST THIS
     AFTERNOON FOR THE FOLLOWING ZONES: GALVESTON BAY...
     MATAGORDA BAY...WATERS FROM FREEPORT TO THE MATAGORDA SHIP
     CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT
     20 NM.

     SMALL CRAFT ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR THE
     FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
     CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
     FREEPORT 20 TO 60 NM.

&&

$$

DISCUSSION...38






AREA FORECAST DISCUSSION

NWS CHEYENNE WY

 306 PM MST WED FEB 8 2012

.SHORT TERM...
CURRENTLY SOME STRONGER WINDS INTO THE ARLINGTON AREA AS WELL AS
NEAR VEDAUWOO WITH SUSTAINED WINDS AROUND 40 MPH AND GUSTS
GENERALLY AROUND 50 MPH. THESE WINDS ARE LARGELY IN RESPONSE TO
THE SHORTWAVE CURRENTLY MOVING ACROSS THE BLACK HILLS OF SOUTH
DAKOTA. AS THE WAVE CONTINUES SOUTHEAST THIS AFTERNOON THE GRADIENT
WILL RELAX AND WIND WILL DECREASE. 2 KM WINDS OFF THE THE MEDICINE
BOW PROFILER MAY ALREADY BE SHOWING THIS AS MAGNITUDE DROPPED FROM
40 KTS TO 35 KTS. ALTHOUGH THE GRADIENT WILL DECREASE...MODELS
INDICATE A STABLE LAYER BEING PUSHED TO THE SURFACE THIS EVENING
AS SUBSIDENCE KICKS IN BEHIND THE SHORTWAVE. COULD SEE SOME GUSTY
WINDS LATER THIS EVENING INTO LATER TONIGHT FOR AREAS LEE OF THE
LARAMIE RANGE...MAINLY FROM INTERSTATE 25 WEST. NOT LOOKING AT
ANYTHING TOO STRONG...BUT 20 TO 25 MPH WITH GUSTS 30 TO 35 MPH
SEEM LIKE A GOOD BET.

FOG OVER THE NEBRASKA PANHANDLE THIS MORNING HAS LIFTED AND PUSHED
WELL TO THE EAST DUE TO MIXING AND LIGHT WESTERLY FLOW. NOT OVERLY
CONCERNED THAT FOG WILL REFORM TONIGHT ALTHOUGH NOT ABLE TO RULE
IT OUT COMPLETELY FROM ROUGHLY EAST OF A LINE FROM CHADRON TO
SYDNEY. GUIDANCE AND HRRR INDICATE FOG COULD FORM LATE TONIGHT IN
THIS AREA. THINKING IS LIGHT WESTERLY FLOW WILL KEEP WIDESPREAD
DENSE FOG AT BAY BUT DID ADD PATCHY FOG INTO THE WESTERN TIER OF
COUNTIES.

PRECIPITATION CHANCES TONIGHT WILL BE CONFINED TO AREAS WEST OF THE
LARAMIE RANGE...MAINLY OVER THE SNOWY AND SIERRIA MADRES. RADAR
INDICATING SOME PRECIPITATION ALREADY REACHING IN THE GROUND IN
THESE AREAS AND OLD BATTLE SNOWTEL SHOWED SOME LIGHT ACCUMULATION
THIS AFTERNOON. MAIN SURGE OF UPSLOPE MOISTURE WILL BE THIS
EVENING WHEN SEVERAL INCHES OF SNOW ARE LIKELY IN HIGHER
ELEVATION. SNOW WILL MOSTLY TAPER OFF BY LATE TONIGHT.

THURSDAY WILL BE A DRY WITH A WEAK RIDGE SHIFTING INTO THE AREA
BUT CHANCES FOR PRECIPITATION WILL INCREASE THURSDAY NIGHT INTO
FRIDAY AS AN UPPER TROUGH DIVES INTO THE NORTHERN PLAINS AND
ASSOCIATED ARCTIC FRONT BACKS INTO THE HIGH PLAINS. MODELS
STRUGGLING TO REACH CONSENSUS AS TO HOW FAR WEST THE FRONT WILL
MAKE IT AND TO THE PLACEMENT AND EXTENT OF SNOW. GFS HAS BEEN
CONSISTENTLY FARTHER EAST WITH THIS SYSTEM...KEEPING THE BULK OF
THE SNOW AND COLD AIR ACROSS WESTERN NEBRASKA. GEM...NAM...AND EC
ALL FARTHER WEST WITH THE EC BEING THE MOST BULLISH ON QPF
AMOUNTS. INCREASED POPS ACROSS THE CWA BUT CONFIDENCE IN AMOUNTS
AND PLACEMENT ARE CURRENTLY LOW. WILL WAIT TO SEE WHAT THE
UPCOMING MODELS BRING BUT IT SHOULD BE NOTED THAT WERE THE EC TO
VERIFY...SOME LOCATIONS ALONG AND LEE OF THE LARAMIE RANGE...COULD
PICK UP OVER 6 INCHES OF SNOW...INCLUDING CHEYENNE.



.LONG TERM...
SATURDAY WILL BE UNSEASONABLY COOL ACROSS THE CWA WITH STRATUS TO
THE EAST OF THE LARAMIE RANGE.  A 1040MB SFC HIGH ACROSS THE PLAINS
WILL CAUSE SOUTHEASTERLY SFC UPSLOPE.  BUMPED UP POPS INTO THE
SLIGHT CHANCE CATEGORY FOR AREAS EAST OF THE LARAMIE RANGE...HOWEVER
ANY SNOW AMOUNTS WILL BE VERY LIGHT.  A SHORTWAVE RIDGE PROGRESSES OVER
THE AREA ON SAT NIGHT IN ADVANCE OF A LOW PRESSURE SYSTEM PROGGED TO
TRACK SOUTH OF THE CWA ON SUNDAY.  THE STRONGEST DYNAMICS WILL BE
WELL SOUTH OF SOUTHEAST WY IN NEW MEXICO AND SOUTHERN CO.  IN
ADDITION...WITH A SFC TROUGH FCSTED TO DEVELOP OVER WESTERN NEBRASKA
AND THE ASSOCIATED LACK OF UPSLOPE ON THE PLAINS...THIS SYSTEM WILL
BE PRIMARILY DRY FOR THE CWA.  HOWEVER...CAN NOT RULE OUT A FEW SNOW
SHOWERS ACROSS THE SIERRA MADRE/SNOWY RANGE WITH MOISTENING 700MB
WESTERLY FLOW. THE GFS AND ECMWF AGREE ON DIGGING ANOTHER SYSTEM
INTO THE INTERMOUNTAIN WEST ON MONDAY.  THE GFS SHOWS THE 700MB LOW
AND SFC LOW TRACKING ACROSS SOUTHERN CO ON TUESDAY...WITH LOW-LEVEL
NORTH AND NORTHEAST WINDS DEVELOPING ACROSS THE PLAINS.  LOOKS LIKE
A BETTER SHOT AT PRECIP ON TUESDAY NIGHT/WEDNESDAY TO THE EAST OF
THE LARAMIE RANGE THAN WITH THE SUNDAY SYSTEM.  THE ECMWF IS ABOUT
12 HOURS WITH THE UPPER TROUGH AND ASSOCIATED PRECIP DEVELOPMENT.
WILL CONTINUE TO MONITOR THE EVOLUTION OF THE TUESDAY/WEDNESDAY
SYSTEM DUE TO ITS POTENTIAL TO PRODUCE MODERATE SNOW ACCUMULATIONS.

&&

.AVIATION...18Z TAF ISSUANCE...
VISIBLE SATELLITE IMAGERY SHOWS THAT THE LOW CLOUDS HAVE CLEARED
OUT OVER THE WESTERN NEBRASKA PANHANDLE...EXCEPT FOR KAIA WHICH IS
ON THE WESTERN FRINGE OF THE LOW CLOUDS. INCLUDED TEMPO MVFR CIGS
THROUGH 19Z AT KAIA TO ACCOUNT FOR THE SLOWER CLEARING AT THIS
SITE. ELSEWHERE VFR CONDITIONS WILL PREVAIL THROUGH THE TAF
PERIOD. MID LEVEL CLOUDS WILL BE PERSISTENT ACROSS SOUTHEAST WY
WITH BKN VFR CIGS THROUGH THE EVENING.


&&

.FIRE WEATHER...
NO FIRE WEATHER CONCERNS THE NEXT SEVERAL DAYS. A BIT BREEZY
THURSDAY FOR FAR SOUTHEAST WYOMING AND THE NEBRASKA PANHANDEL BUT
MIN RH WILL MAINLY BE ABOVE 35 PERCENT. CHANCE FOR SNOW ACROSS
MOST OF THE AREA FRIDAY WITH COLD AIR FILTERING INTO THE AREA
FRIDAY NIGHT. COOL AND UNSETTELED WEATHER INTO EARLY NEXT WEEK.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.

&&

$$

SHORT TERM/FIRE WEATHER...LIEBL
LONG TERM/AVIATION...FINCH