FXUS63 KMPX 252133
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
333 PM CST FRI DEC 25 2009

.DISCUSSION...

MESSY AND VERY COMPLICATED STORM SYSTEM LOSING IT MAIN PUNCH...BUT
WILL CONTINUE TO IMPACT THE AREA FOR ANOTHER 24 HOURS OR SO.
TRIMMED BACK THE HEADLINES SOMEWHAT LATE THIS MORNING IN EASTERN
CWA...AND HAVE CUT BACK ON MORE HEADLINES WITH THIS ISSUANCE.

SURFACE LOW HAS BEEN TRACKING STEADILY NW ACROSS IOWA TODAY 
AND IS NOW NEAR FORT DODGE. IT HAS MAINTAINED A CENTRAL PRESSURE
OF 987 MB. WITH PRESSURE FALLS STILL WEST OF SFC LOW IT WILL
PROBABLY TRACK A BIT FARTHER WEST BEFORE UPPER LOW PULLS IT BACK
EAST. VERY WELL DEFINED VIGOROUS VORT MAX WHICH ROTATED AROUND
UPPER LOW IS NOW NEAR ST. JAMES AND CONTINUING TO PUSH WNW.
ANOTHER WEAKER VORT PUSHING ACROSS ILLINOIS IS EXPANDING ANOTHER
AREA OF PRECIP ACROSS SW WI WHICH WILL SPREAD INTO CWA LATER THIS
EVENING. WARM WEDGE OF AIR ACROSS WC WI INTO E MN WHICH HAS
PESTERED US WITH A MIX WILL DISAPPEAR THIS EVENING AS COOLER AIR
WRAPS IN FROM THE SOUTH. SURFACE TEMPS IN NE IA HAVE FALLEN FROM
THE MID 30S INTO THE UPPER 20S LAST COUPLE OF HOURS. WE MAINTAIN
SOME WEAK BUT PERSISTENT ISENTROPIC LIFT OVERNIGHT ACROSS N INTO
WC MN. THIS MAY PRODUCE ANOTHER 2-4 INCHES OF SNOW...THUS WILL
MAINTAIN THE WARNING IN WC MN. WINDS GUSTING TO 25 TO 30 MPH WILL
ALSO PRODUCE SOME BLOWING OR DRIFTING NEAR THE DAKOTAS BORDER. 
DOWNGRADED TO AN ADVISORY OVERNIGHT FOR A SWATH OF COUNTIES ACROSS
CENTRAL INTO SC MN FOR 1-3 INCHES SNOW...AND REMOVED HEADLINES
FROM THE TC METRO TO AEL THEN EWRD ACRS WC WI. MAY SEE AN INCH OR
SO ACCUMULATE OVERNIGHT.

-SN WILL CONTINUE ACROSS AREA OF SATURDAY/SATURDAY NIGHT AS LOW
FILLS AND WOBBLES AROUND WISCONSIN. RATHER UNUSUAL TEMPERATURE
FORECAST NEXT 24 HOURS WITH COLDEST AIR NEAR THE CORE OF LOW
PRESSURE...SO TONIGHT'S MINS AND TOMORROWS MAX TEMPS COOLEST IN SE
MN INTO WI. 

WITH A FORMIDABLE SNOW PACK ACROSS THE AREA TEMPERATURES COULD
TUMBLE...BUT WILL WILL MAINTAIN MOSTLY CLOUDY SKIES NEXT FEW DAYS
WHICH WILL LIMIT FALLS. 

WEAK FAST MOVING SHORTWAVES MOVING ACROSS AREA WED/THURS WILL
BRING CHC -SN...MAINLY TO NE CWA. 

&&

.AVIATION.../18Z TAF ISSUANCE/ 

PERIODS OF PRECIPITATION AND LOW CIGS/VSBYS WILL CONTINUE THROUGH
MUCH OF THE PERIOD AS STRONG LOW PRESSURE OVER CENTRAL IOWA MOVES
LITTLE BUT BEGINS TO WEAKEN. WAVES OF PRECIPITATION WILL CONTINUE
TO ROTATE WESTWARD ACROSS THE TERMINALS THIS AFTERNOON WITH MIXED
PRECIPITATION EAST AND ALL SNOW WEST. TREND WILL BE TO FOCUS SNOWFALL
ACROSS WEST CENT MN THIS EVENING AND TONIGHT WITH LIGHTER PRECIP
EAST. MVFR/IFR CIGS WILL CONTINUE WITH MOSTLY MVFR VSBY EXCEPT FOR
IFR AND LOWER VSBY IN MORE INTENSE SNOW BANDS. MIXED PRECIP WILL
END THIS EVENING AS COLDER AIR ARRIVES FROM THE SOUTHEAST WITH
SNOWFALL COVERAGE AND INTENSITY DECREASING WITH TIME EAST AS WELL. STRONG
NORTHEAST WINDS WILL SLACKEN THIS EVENING BUT BLOWING SNOW WILL
CONTINUE IN THE WEST UNTIL THIS OCCURS. DETAILS BELOW...

KMSP...THE TERMINAL SITES RIGHT ON THE FRINGE OF WARMER AIR IN THE
LOW LEVELS SO MIXED PRECIP CONTINUES. TREND WILL BE FOR MAINLY SNOW
BUT AT LEAST A LITTLE RAIN AND SLEET WILL CONTINUE TO MIX IN
EARLY THIS AFTERNOON...BUT FOR SHORTER AND SHORTER PERIODS.
PRECIP INTENSITY WILL START TO DECREASE AS THE CURRENT BAND SHIFTS
WESTWARD. ENOUGH FORCING WILL BE PRESENT INTO THE EVENING TO KEEP
SNOW SHOWERS GOING SO KEPT LOWERED VSBY IN LIGHT SNOW AND MIST
THROUGH TONIGHT. EXPECT CIGS OF 1000-1500 FT THROUGH TONIGHT WITH
SOME IMPROVEMENT EXPECTED SATURDAY. SNOW SHOWERS WILL CONTINUE
SATURDAY BUT WILL BE MUCH LESS PERSISTENT.

KAXN/KRWF/KSTC...BAND OF BETTER FORCING MOVING INTO THESE SITES AT
18Z BRINGING A HEAVIER PERIOD OF SNOW. TOUGH TO GET A GOOD
HANDLE ON VSBY AS THE PRECIP IS CHANGING FROM RAIN TO SNOW AS IT
APPROACHES BUT EXPECT REDUCTIONS TO AROUND 3/4SM AND POSSIBLY
LOWER THIS AFTERNOON. BANDS OF SNOW WILL CONTINUE ON AND OFF
THROUGH THE NIGHT WITH VSBY FALLING TO LESS THAN 1SM IN THE
HEAVIEST BANDS INTO SATURDAY MORNING. BLOWING SNOW WILL LIKELY
OCCUR AS THE NEW SNOW FALLS AND WINDS STAY UP BUT WINDS WILL
SLACKEN THIS EVENING SO BLOWING SHOULD BE MINIMIZED BY EARLY SATURDAY.

KRNH/KEAU...WARMER AIR REMAINS IN THE LOW LEVELS WHICH CONTINUES TO
BRING MIXED PRECIPITATION TO THESE SITES. TENDENCY WILL BE FOR THE
ATMOSPHERE TO COOL BUT PRECIP COVERAGE WILL BEGIN TO WANE TOO.
TRANSITION FROM MIX TO ALL SNOW WILL OCCUR THIS AFTERNOON WITH
ENOUGH ENERGY TO KEEP LIGHT PRECIP FALLING. WITH ABUNDANT LOW
LEVEL MOISTURE HAVE KEPT MIST IN AS WELL. TOUGH T0 TIME ANY
SIGNIFICANT REDUCTIONS IN VSBY BUT THEY SHOULD BE SHORT LIVED WITH
THE FORCING NOT THAT WELL FOCUSED. CIGS WILL STAY DOWN TO AROUND
1000 OR 1500 FT WITH SOME IMPROVEMENT POSSIBLE FOR SATURDAY. SNOW
SHOWERS WILL CONTINUE ON AND OFF FOR SATURDAY. ..MDB..

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER STORM WARNING UNTIL 6 AM CST SATURDAY FOR CHIPPEWA-
     DOUGLAS-LAC QUI PARLE-POPE-REDWOOD-STEVENS-SWIFT-TODD-
     YELLOW MEDICINE.

     WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR BENTON-BLUE 
     EARTH-BROWN-FARIBAULT-ISANTI-KANABEC-KANDIYOHI-MARTIN-
     MCLEOD-MEEKER-MILLE LACS-MORRISON-NICOLLET-RENVILLE-
     SHERBURNE-SIBLEY-STEARNS-WATONWAN-WRIGHT.

WI...NONE.
&&

$$

BAP/MDB