National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS63 KMPX 291746
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1146 AM CST FRI NOV 29 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 407 AM CST FRI NOV 29 2013

COLD START TO THIS FRIDAY UNDER INFLUENCE OF DEPARTING SURFACE HIGH
PRESSURE RIDGE.  SNOW COVER LIMITED TO THE FAR NORTHEAST PERIPHERY OF
THE CWA...MAINLY IN WEST CENTRAL WISCONSIN.  THIS WILL LIMIT
TEMPERATURES SOMEWHAT AS THIS REGION WILL REMAIN UNDER THE INFLUENCE
OF THE HIGH TODAY.  SOME WAA DEVELOPING TO THE WEST...AS THE HIGH
DEPARTS THE AREA AND SURFACE WINDS INCREASE FROM THE SOUTH.  SHOULD
SEE SOME GUSTS APPROACHING 25 KTS IN THE AFTERNOON OVER THE
SOUTHWEST.  THIS SHOULD PROVIDE SOME DOWNSLOPE OVER THE SOUTHWEST
CWA...PROVIDING SOME HIGH TEMPERATURES IN THE MID 30S.  THE
REMAINDER OF THE AREA WILL REMAIN IN THE UPPER 20S TO LOWER 30S.
EXPECT A FAIR AMOUNT OF MID/HIGH LEVEL CLOUDS TO DEVELOP OVER THE
AREA IN THE WAA PATTERN.

MODELS SUGGEST SOME LOWER LEVEL CLOUDS DEVELOPING OVER THE EASTERN
CWA LATER THIS AFTERNOON. THE NAM 290K ISENTROPIC SURFACE IS
INDICATE SATURATION OCCURRING OVERNIGHT/MAINLY AFTER 03Z/IN THE FAR
NORTHEAST CWA.  THE GFS SHOWS LESS SO OF THE POSSIBILITY.  STILL MAY
BE ENOUGH FOR A SLIGHT CHANCE OF SNOW IN THE FAR NORTHEAST LATE
TONIGHT. CANT ARGUE WITH THE CONS POPS GIVEN AT THIS TIME. WINDS
WILL BE SLOW TO DIMINISH THIS EVENING AND ARE NOT EXPECTED TO
DECOUPLE FROM THE BOUNDARY LAYER MOST AREAS AS GRADIENT REMAINS. LOW
TEMPERATURES ARE EXPECTED TO REMAIN IN THE TEENS TO LOWER 20S.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 407 AM CST FRI NOV 29 2013

THE PATTERN IS SET TO BECOME MUCH MORE ACTIVE DURING THE LONG
TERM...PARTICULARLY NEXT WEEK. THIS WEEKEND WILL REMAIN TRANQUIL
AS ONE CLIPPER SYSTEM TRAVERSES SOUTHERN ONTARIO SATURDAY AND HIGH
PRESSURE BUILDS OVER MINNESOTA SATURDAY NIGHT AND EARLY SUNDAY.
TEMPERATURES WILL BE ABOUT AVERAGE...ALTHOUGH SATURDAY NIGHT MAY
BE A BIT CHILLY WITH FULL DECOUPLING ANTICIPATED UNDER HIGH
PRESSURE.

AS A SHARP TROUGH BEGINS TO DIG INTO THE PACIFIC NORTHWEST SUNDAY
NIGHT...A WEAK IMPULSE WILL BREAK OFF AND PROPAGATE SOUTHEAST
ACROSS THE NORTHERN PLAINS AND UPPER MIDWEST. SOME ISENTROPIC LIFT
FROM THE WEST IN CONJUNCTION WITH INCREASING MOISTURE SHOULD RESULT
IN A BAND OF LIGHT SNOW POLEWARD OF THE MID LEVEL IMPULSE SUNDAY
NIGHT AND MONDAY MORNING. THE SNOW MAY PERSIST INTO MONDAY NIGHT
ALONG A BAND OF STRETCHED VORTICITY MAXIMA FROM ND INTO SRN
MN...BUT THIS WILL BE GOVERNED BY THE DEPTH OF MOISTURE INTO THE
MID LEVELS WHICH FORECAST SOUNDINGS INDICATE MAY NOT PERSIST.
THUS...MAINTAINED CHC POPS EARLY NEXT WEEK WITH THE HIGHEST PROBS
SUNDAY NIGHT.

THE EVOLUTION OF THE TROUGH DIGGING SOUTH INTO THE CENTRAL ROCKIES
WILL DETERMINE THE ODDS OF A WINTER STORM IN THESE PARTS AROUND
MIDWEEK...THE RESULTANT SNOWPACK...FOLLOWED BY THE DEGREE OF
EXTREME COLD INTO MID DECEMBER. THE COLD WILL BE DISCUSSED LATER.
OPERATIONAL MODELS CONTINUE TO DIFFER IN HANDLING THIS
TROUGH...BUT ONE WOULD THINK WITH HOW FAR SOUTH IT DIGS THAT
PHASING OF THE POLAR AND SUBTROPICAL JETS WOULD BE ACHIEVED. THE
CANADIAN MODEL ACCOMPLISHES THIS THE QUICKEST WHICH IS REFLECTED
IN A MUCH DEEPER SURFACE CYCLONE OVER THE MID MISSISSIPPI VALLEY
TUESDAY NIGHT. THE GFS AND ECMWF ARE CLOSER TO THE ENSEMBLE MEANS
WHICH WERE PREFERRED. IF THE UPPER LOW BECOMES DETACHED FROM THE
NORTHERN STREAM...A SLOWER AND DRIER EVOLUTION WOULD PLAY OUT. SO
FAR...THE MODELS DO NOT AND HAVE NOT INDICATED THIS POTENTIAL.
BEST BET IS FOR A SURFACE CYCLONE TO EMERGE OVER THE PLAINS
TUESDAY NIGHT AND TRACK NORTHEAST ACROSS THE UPPER MISSISSIPPI
VALLEY LATE WEDNESDAY. MAINTAINED HIGH CHC POPS FOR NOW UNTIL
MODEL SOLUTIONS STABILIZE FURTHER.

BEHIND THE SYSTEM...VERY COLD AIR IS POISED TO DIVE INTO THE
WESTERN AND CENTRAL CONUS AS RIDGING OVER AK FORCES THE POLAR
VORTEX SOUTH INTO CANADA. ONCE IT DOES SO...IT WILL BE HARD TO
KICK IT BACK NORTH SO THE FIRST HALF OF DECEMBER COULD END UP
BEING CONSIDERABLY BELOW AVERAGE IN THE TEMPERATURE DEPARTMENT.
IN FACT...THE 00Z EC HAS 2M TEMPS IN THE -20S FOR HIGHS AND -30S
TO AROUND -40 FOR LOWS OVER PORTIONS OF ND AND MT NEXT WEEKEND.
THAT KIND OF COLD WOULD RIVAL THE FEB 1996 COLD AIR OUTBREAK UP
THERE. SEVERAL STRONG SURFACE HIGHS WILL PERIODICALLY REINFORCE
THE COLD AIR OUT TO DAY 10 AND BEYOND. IF WE END UP WITH A GOOD
SNOWPACK NEXT WEEK...TEMPS AROUND HERE MAY BE THE COLDEST IN
SEVERAL YEARS AS WELL.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1130 AM CST FRI NOV 29 2013

NO AVIATION PROBLEMS THRU 6Z WITH WINDS GENERALLY INCREASING
DURING THE AFTN WITH GUSTS UP TO 20-24 KTS IN WESTERN MN. SOME
CONCERNS ACROSS EASTERN MN/WESTERN WI AS BOUNDARY LAYER MOISTURE
MAY INCREASE DURING THE OVERNIGHT HRS ALLOWING FOR FG/BR TO FORM
ALONG WITH THE POSSIBILITY OF MVFR/IFR CIGS. ALTHOUGH CONFIDENCE
IS LOW ON THE DEVELOPMENT OF LOWER VSBYS/CIGS AFT 6Z...THERE
REMAINS ENOUGH CONFIDENCE TO INTRODUCE SCT008/SCT015 AT BOTH
KEAU/KRNH AFT 12Z. WINDS WILL DECREASING DURING THE EVENING TO
LESS THAN 6 KTS AND SHIFT TO THE W/NW DURING THE MORNING IN
WESTERN MN...AND BY 15-18Z IN EASTERN MN.

KMSP...

CONFIDENCE IS HIGH ON VFR CONDS THRU 6Z WITH WINDS GENERALLY FROM
THE SE/SSE ARND 10-12 KTS...WITH A FEW AFTN GUSTS ARND 18 KTS.
THESE WINDS WILL DECREASE TO LESS THAN 6 KTS OVERNIGHT AND SHIFT
TO THE WEST/NW BY MID/LATE MORNING. THERE REMAINS SOME CONCERN
WITH THE DEVELOPMENT OF MVFR CIGS WITH PATCHY BR/FZDZ AFT 9Z AS
THE BOUNDARY LAYER MOISTURE MAY MOISTEN UP. MOISTURE TRANSPORT BLW
90H IS INCREASING AFT 6Z IN EASTERN MN/WESTERN MN. THERE WERE SOME
IFR CIGS IN WESTERN KANSAS EARLIER TODAY...AND THIS MAY ADVECT TO
THE NE ACROSS NE/IA DURING THE EVENING HRS.

/OUTLOOK FOR KMSP/

SUN...VFR...POSSIBLY MVFR CIGS LATE WITH -SN. WINDS E/SE AT 5 KTS.
MON...CIGS/VSBYS LOWERING WITH -SN DEVELOPING. SE WINDS 10 KTS.
TUE...IFR/MVFR CIGS IN -SN...POSSIBLY MIXED WITH RA BY AFTN. SE
10-15 KTS.

&&

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

$$

SHORT TERM...DWE
LONG TERM...BORGHOFF
AVIATION...JLT