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000
FXUS63 KARX 120844
AFDARX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
344 AM CDT WED MAR 12 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 220 AM CDT WED MAR 12 2014

AT 3 AM...A 976 MB SURFACE LOW WAS LOCATED OVER SOUTHERN ILLINOIS.
MSAS SHOWS PRESSURE FALLING ACROSS THE OHIO VALLEY. AS A
RESULT...EXPECT THIS LOW TO CONTINUE TO TRACK EAST TOWARD
PITTSBURGH TODAY. NORTHEAST OF THIS LOW THERE IS AN INVERTED
TROUGH THAT EXTENDS NORTHEAST INTO NORTH CENTRAL WISCONSIN. THE
ONLY SNOW IN THIS TROUGH IS LOCATED OVER NORTHEAST WISCONSIN AND
IT IS BEING CAUSED MORE BY A LAKE EFFECT BAND THAN BY THE TROUGH.

FOR TODAY...THE 12.00Z NMM...ARW...AND MANY OF THE DETERMINISTIC
MODELS CONTINUE TO GENERATE SNOW SHOWERS. BUFKIT SOUNDINGS ACROSS
CENTRAL AND SOUTHWEST WISCONSIN AND NORTHEAST IOWA CONTINUE TO
SHOW 900 TO 850 MB LAPSE RATES UP TO 9 C/KM. HOWEVER THEIR SURFACE
TEMPERATURES ARE RUNNING 3 TO 5F TOO HIGH AND THE MODELS ARE
ALREADY OVERDOING THE PRECIPITATION IN THIS TROUGH. DUE TO
THIS...TOOK OUT THE MENTION OF SNOW OUT OF THE FORECAST.

FOR THIS EVENING...THE COMBINATION OF LIGHT WINDS...VERY DRY DEW
POINTS...AND MOSTLY CLEAR TO PARTLY CLOUDY SKIES WILL CAUSE
TEMPERATURES TO RAPIDLY FALL ACROSS NORTH CENTRAL AND CENTRAL
WISCONSIN. BY MIDNIGHT...TEMPERATURES WILL BE IN THE 0 TO 5F
DEGREE RANGE.

AFTER MIDNIGHT...STRONG WARM AIR ADVECTION /850 MB TEMPERATURES
WARM 6 TO 8C/ OCCURS ACROSS THE AREA AS A SHORT WAVE RIDGING
DEVELOPS AHEAD OF THE SASKATCHEWAN TROUGH. BOTH THE GFS AND NAM
SHOW A BAND OF STRONG 900 TO 800 MB FRONTOGENESIS MOVING ACROSS
THE AREA. IN ADDITION...THE 280 TO 290K ISENTROPIC UPGLIDE MOVES
INTO AREA. THIS RESULTS IN SOME LIGHT SNOW IN THEM. MEANWHILE THE
GEM AND ECMWF ARE HAVING DIFFICULTIES SATURATING THE DRY AIR BELOW
700 MB. AS A RESULT...THEY ARE DRY. WITH SOME DIFFERENCES OF
OPINIONS...LOWERED THE SNOW CHANCES A BIT FOR TONIGHT.


.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 220 AM CDT WED MAR 12 2014

ON FRIDAY MORNING...A COLD FRONT MOVES THROUGH THE AREA. THE
12.00Z MODELS CONTINUE TO SHOW THAT THE PV ADVECTION WILL REMAIN
ACROSS NORTHERN AND EASTERN WISCONSIN. DUE TO THIS KEPT...A
MENTION OF PRECIPITATION NORTH OF INTERSTATE 94.

ON SATURDAY MORNING...ANOTHER CANADIAN COLD FRONT WILL MOVE SOUTH
THROUGH THE AREA. THIS FRONT WILL BRING MUCH COLDER AIR INTO THE
AREA FOR THE WEEKEND. 850 MB TEMPERATURES FALL INTO THE -8 TO -16C
RANGE. DUE TO THIS EXPECT...THE HIGH TEMPERATURE ON SATURDAY TO
OCCUR DURING THE MORNING...AND THEN SEE TEMPERATURES SLOWLY FALL
FOR THE REMAINDER OF THE DAY.

WHILE THE MODELS ARE IN GENERAL AGREEMENT THAT WARM AIR ADVECTION
WILL DEVELOP ACROSS THE AREA ON SUNDAY NIGHT. THEY CONTINUE TO
STRUGGLE WITH WHERE THE POLAR JET WILL BE LOCATED AND THIS GREATLY
AFFECTS WHERE THE STORM TRACK WILL BE LOCATED. AS A RESULT...THERE
HAS BEEN VERY LITTLE TO RUN TO RUN CONSISTENCY IN THEIR LOW
PRESSURE TRACKS. DUE TO THIS...JUST STAYED WITH THE MODEL
CONSENSUS FOR BOTH TEMPERATURES AND PRECIPITATION FROM SUNDAY
NIGHT THROUGH TUESDAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1041 PM CDT TUE MAR 11 2014

CLOUDS EXTENDING ACROSS NORTHERN MINNESOTA...NORTHERN WISCONSIN
AND UPPER MICHIGAN CONTINUE TO MARCH SOUTHWARD TOWARDS THE TAF
SITES...BROUGHT SOUTH ON A NORTHERLY BREEZE. ONE CHANGE IS THAT
ALL OBSERVATION SITES ARE REPORTING VFR CONDITIONS WITH THESE
CLOUDS. BELIEVE THIS IS A RESULT OF DRIER AIR ACCOMPANYING THE
BREEZE WHICH IS EVIDENT BY FALLING DEWPOINTS. THEREFORE...THE TAF
FORECAST STILL REFLECTS THE LOWER CLOUDS COMING THROUGH BUT BASES
ARE NOW VFR. THE VFR CONDITIONS ARE LIKELY TO PERSIST THROUGH THE
EVENING HOURS. TOWARDS 06Z WEDNESDAY NIGHT...THERE ARE INDICATIONS
OF SOME SNOW THAT COULD MOVE INTO RST FROM THE WEST...BUT THE BULK
OF THE PRECIPITATION LOOKS TO HOLD OFF UNTIL AFTER THE TAF PERIOD.

REGARDING WINDS...SPEEDS WILL STAY SUSTAINED 10 TO 15 KT
TODAY...STRONGEST THIS MORNING...DUE TO A RELATIVELY TIGHT
PRESSURE GRADIENT IN PLACE. EXPECT THE WINDS TO DIMINISH THIS
AFTERNOON AND EVENING AS HIGH PRESSURE BRIEFLY BUILDS IN.


&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&

$$

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