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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1104 PM CST THU NOV 27 2014

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 327 PM CST THU NOV 27 2014

MAIN CONCERN IS TIMING OF SNOW AND THE ATTENDANT HEADLINE OVER THE 
NORTHEAST CWA. 

MODELS TREND A BURST OF WAA SNOW ACROSS THE CWA DEVELOPING OVER 
WEST AND CENTRAL MINNESOTA THIS EVENING...AND SPREADING INTO WEST 
CENTRAL WISCONSIN MAINLY AFTER MIDNIGHT.  WITH CLOUDS 
INCREASING...SHOULD SEE TEMPERATURES STOP THEIR DECLINE...WHICH WILL 
LIKELY BE RAPID TO THE EAST THIS EVENING. 

BEST ISENTROPIC LIFT MOVES INTO EASTERN MN BY 06Z AND THE REMAINDER 
OF THE NIGHT OVER WESTERN WISCONSIN.  SNOW AMOUNTS IN THE 2 TO 3 
INCH RANGE ARE EXPECTED FOR THE MOST PART ALONG AND NORTH OF I94 AND 
ALONG AND NORTH OF HIGHWAY 8 IN WISCONSIN. THIS SHOULD GRADUALLY END 
OVER THE NORTHEAST PORTION OF THE CWA FRIDAY MORNING...PERHAPS 
LINGERING A BIT INTO NORTHWEST WISCONSIN INTO THE AFTERNOON. ADDED 
ANOTHER COUNTY EAST/RUSK COUNTY/IN WISCONSIN FOR NOW...BEGINNING 
AFTER MIDNIGHT. THE REMAINDER OF THE ADVISORY LOOKS GOOD. THERE MAY 
BE A BOUT OF FREEZING DRIZZLE ON THE BACK SIDE OF THE WAA WING OF 
SNOW AND ELEVATED WARM LAYER MOVES THROUGH. CONTINUED TO MENTION 
THAT POSSIBILITY AS WELL.  MODELS ALSO GENERATED A SMALL CHANCE OF 
SLEET...WHICH COULD BE POSSIBLE IF THE WATER DROPLETS REFREEZE IN 
THE COOLER AIR NEAR THE GROUND. AGAIN...THIS WOULD OCCUR ON THE WEST 
END OF THE SNOW AREA...AS IT MOVES EAST INTO WISCONSIN FRIDAY 
MORNING. 

FRIDAYS HIGH TEMPERATURES WILL REMAIN IN THE 20S FOR THE MOST 
PART...PERHAPS SOME READINGS AROUND 30 IN THE FAR SOUTHWEST CWA.  
EXPECT CLOUDS TO REMAIN HOWEVER.    

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 327 PM CST THU NOV 27 2014

FRIDAY NIGHT AND SATURDAY...THE STRONGEST WAA AND ASSOCIATED LIFT 
WILL BE NORTH OF THE FA BY FRIDAY NIGHT.  SOME WEAK WAA ALOFT STILL 
EXPECTED THROUGH THE NIGHT...HOWEVER 900-700H DRYING WILL INHIBIT ANY 
VERY LIGHT PRECIP THAT MAY TRY TO REACH THE GROUND.  CLOSER TO THE 
SURFACE...SATURATED SOUNDINGS WITH INCREASING DEW POINT TEMPERATURES 
STILL INTRODUCE THE CONCERN FOR FOG...AT LEAST IN SOUTHERN MINNESOTA 
OVERNIGHT THROUGH SATURDAY MORNING. 850H TEMPS SHOULD WARM TO +8 TO 
+12C BY EARLY SATURDAY MORNING.

SATURDAY THROUGH SATURDAY NIGHT...WARM ADVECTION WILL CONTINUE OVER 
THE ENTIRE CWA SATURDAY MORNING.  DECENT ISENTROPIC LIFT WITH 
RELATIVELY MOIST AIR MOVING OVER THE SNOWPACK SHOULD PROMOTE THE 
DEVELOPMENT OF A STRATUS DECK ESPECIALLY IN NORTHERN 
LOCATIONS...WHICH COULD PERSIST MUCH OF THE DAY.  THE GFS AND NAM 
ALSO DEVELOP SOME SPOTTY, VERY LIGHT PRECIPITATION OVER PARTS OF OUR 
REGION DURING THIS TIME...BUT THE ECMWF HAS NOTHING. WITH THE BEST 
FORCING TO THE NORTH OF OUR REGION...WILL NOT INTRODUCE PRECIP INTO 
THE GRIDS.  CLOUD COVER WILL LIKELY SUPPRESS WARMING...ESPECIALLY IN 
NORTHERN AND EASTERN PARTS OF THE CWA. HOWEVER...ENOUGH BREAKS IN 
THE CLOUD DECK AND CONTINUED WARM ADVECTION SHOULD LIFT SOME 
SOUTHERN AREAS INTO THE 40S DURING THE AFTERNOON...ESPECIALLY IN 
LOCATIONS THAT DID NOT RECEIVE SIGNIFICANT SNOW FROM WEDNESDAY'S 
STORM.  A COLD FRONT WILL THEN MOVE THROUGH THE AREA FROM NORTHWEST 
TO SOUTHEAST SATURDAY EVENING THROUGH THE OVERNIGHT HOURS. 
MEASURABLE PRECIPITATION IS ONCE AGAIN UNLIKELY WITH THE FRONTAL 
PASSAGE...BUT TEMPERATURES WILL DROP SIGNIFICANTLY BEHIND THE FRONT, 
WITH SOME GUSTY NW WINDS POSSIBLE IN WESTERN MN.

SUNDAY AND BEYOND...THE SEE-SAW OF TEMPERATURES WILL CONTINUE 
THROUGH EARLY SUNDAY MORNING AS STRONG COLD AIR ADVECTION CONTINUES 
FROM THE OVERNIGHT FROPA MENTIONED ABOVE. TEMPERATURES WILL HARDLY 
RECOVER SUNDAY AND BE A SOLID 20 DEGREES COLDER THAN SATURDAY AT 
LEAST. GOOD AGREEMENT ON A VERY STRONG HIGH PRESSURE AREA MOVING IN 
FROM THE NORTHWEST WILL MAKE FOR A VERY COLD START TO THE WORK 
WEEK.  SIGNIFICANTLY LOWERED THE HIGH TEMPS FOR MONDAY TO THE LOWER 
TEENS ACROSS THE REGION. THAT TYPE OF COLD WONT LAST LONG THOUGH AS 
INCREASING SOUTHERLY WINDS ON THE BACK SIDE OF THE HIGH DELIVER SOME 
MODIFICATION TO THE REGION TUESDAY.

THE GFS HAS BEEN ADVERTISING A LARGE CYCLONE MOVING THROUGH THE 
MIDWEST DURING THE MIDDLE OF NEXT WEEK.  IT HAS BEEN SPORADIC WITH 
ITS OVERALL EVOLUTION OF THE PATTERN AND THE ECMWF INDICATES DRY 
WITH A RIDGE OVER THE MIDWEST AT THE SAME TIME.  SO CONFIDENCE IS SO 
LOW IN ANY PRECIPITATION OCCURRING FOR OUR AREA...DECIDED TO KEEP 
THE FORECAST DRY UNTIL AT LEAST SOME AGREEMENT OR CONSISTENCY IS 
SEEN.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1103 PM CST THU NOV 27 2014

A BAND OF WAA SNOW WILL PUSH ACROSS EASTERN MN AND WESTERN WI
EARLY THIS MORNING. CEILINGS AND VISIBILITIES WILL DROP TO IFR FOR
A SEVERAL HOUR PERIOD. IN THE WAKE OF THE BAND OF SNOW...A LOSS OF
MID LEVEL CLOUDS/ICE CRYSTALS IS STILL SEEN IN SHORT TERM
GUIDANCE. THIS MAY LEAD TO SOME LIGHT FREEZING DRIZZLE FRIDAY
MORNING. CONFIDENCE IS NOT REAL HIGH ON OCCURRENCE AND A PROB
GROUP WAS USED AT MOST OF THE TAF SITES. ANOTHER WEAK WEATHER 
DISTURBANCE WILL MOVE ACROSS CENTRAL MN AND WEST CENTRAL WI FRIDAY
EVENING. PROFILE DATA INDICATES A RATHER SIGNIFICANT WARM LAYER
ALOFT WITH SLEET BEING THE PRECIPITATION TYPE. CONFIDENCE IS NOT
HIGH ON THIS OCCURRING AS IT HAS RECENTLY BEGUN TO SHOW UP IN MODEL
DATA THIS EVENING. AGAIN...USED A PROB GROUP FROM KSTC THROUGH
KEAU. SE WINDS 6-12 KNOTS OVERNIGHT BECOMING ESE 4-6 KNOTS FRIDAY
AFTERNOON AND EVENING. 

KMSP...A BAND OF IFR SNOW WILL MOVE THROUGH IN THE 06Z-08Z TIME
FRAME WITH MVFR CONDITIONS/-SN THROUGH DAYBREAK. SNOW ACCUMULATION
OVERNIGHT UP TO AN INCH. A THREAT REMAINS FRIDAY MORNING/EARLY
AFTERNOON FOR SOME FREEZING DRIZZLE. MOVED THE OCCURRENCE TO A PROB
GROUP DUE TO LOWER CONFIDENCE. PUSHED CEILINGS TO VFR FRIDAY
EVENING AS THE WARM FRONT MOVES EAST OF THE AIRFIELD.

/OUTLOOK FOR KMSP/
SAT...MVFR CIGS. WINDS S AT 5-10 KTS.
SUN...VFR. WINDS NW AT 15G20 KTS. 
MON...VFR. WINDS NW AT 5-10KTS...BECOMING S LATE

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL 4 PM CST FRIDAY FOR MNZ042>045-050-
     052-053.

WI...WINTER WEATHER ADVISORY UNTIL 4 PM CST FRIDAY FOR WIZ014-015.

     WINTER WEATHER ADVISORY UNTIL 4 PM CST FRIDAY FOR WIZ016.

&&

$$

SHORT TERM...DWE
LONG TERM...SPD
AVIATION...RAH




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