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000
FXUS63 KMPX 101141 AAA
AFDMPX

AREA FORECAST DISCUSSION...UPDATED FOR 12Z TAFS
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
540 AM CST WED FEB 10 2010

.DISCUSSION...

THE FORECAST CHALLENGES ARE TEMPERATURES TODAY AND TONIGHT
FOLLOWED BY SNOW CHANCES FRIDAY AND SATURDAY.

BELOW NORMAL TEMPERATURES WILL CONTINUE THIS FORECAST CYCLE WITH
NORTHWEST UPPER LEVEL FLOW PREVAILING. THE ARCTIC RIDGE AT 1030
MB IS MOVING OVER THE FRESH SNOW COVER THIS MORNING...CENTERED
OVER THE ERN DAKOTAS AND WRN MN. TEMPERATURES HAVE ACCORDINGLY
BOTTOMED OUT 15 TO 20 BELOW ZERO. RIDGE WILL MOVE GRADUALLY EAST
TODAY WITH A SUNNY SKY EXPECTED. THE EXCEPTIONS ARE WRN WI WHICH
WILL SEE STRATOCU OFF LAKE SUPERIOR THIS MORNING...AND WRN MN
WHICH WILL SEE TOUCHES OF AFTN CIRRUS. WITH THE LOW STARTING POINT
IN TEMPERATURES OVER WRN MN...EVEN WITH A CLIMB OF 5 TO 10 DEGREES
ABOVE THE NORMAL DIURNAL RANGE THIS TIME OF YEAR...TEMPS STILL
LOOK TO BE ONLY IN THE LOW TEENS FOR HIGHS. HAVE ADJUSTED DOWN THE
MAXS TODAY OVER THIS AREA WHERE TEMPS ARE STARTING THEIR COLDEST.

FOR TONIGHT...THE RIDGE AXIS GLIDES EAST OVER ERN MN AND WRN WI
WITH SIMILAR LOWER ATMOSPHERIC TEMPS AND LOW PWATS AS IN THE ERN
DAKOTAS THIS MORNING. EXPECT ONLY A SLOW INCREASE IN CIRRUS AND
ONLY OVERNIGHT OVER THE HEART OF THE RIDGE. SOME OF THE DEEPEST
FRESH SNOW COVER WILL HAVE THE RIDGE OVER IT TONIGHT...FURTHER
MAXIMIZING THE RADIATIONAL COOLING. SREF MEMBER PLUMES FOR
MINNEAPOLIS INDICATE A FAIRLY LARGE OVERALL MEMBER SPREAD SHOWING
MODEL UNCERTAINTY. HOWEVER FORECASTER CONFIDENCE CONTINUES TO
INCREASE IN THE COLDEST MEMBERS COMING TO FRUITION. THIS IS
FURTHER SUPPORTED BY A HANDFUL OF COOPERATIVE INSTITUTE FOR
PRECIPITATION STUDIES /CIPS/ ANALOGS THAT MATCH THE COOLER GFS
FORECAST AND CURRENT SNOW DEPTHS. SO AS PREVIOUS SHIFT...HAVE
BLENDED GOING FORECAST TOWARDS THE MORE FAVORABLE GFS. THINK 10 TO
15 BELOW WILL BE COMMON IN OUTLYING AREAS...JUST A TAD WARMER THAN
WHAT IS BEING EXPERIENCED THIS MORNING TO OUR IMMEDIATE WEST DUE
TO SLIGHTLY WARMER AFTERNOON MAXS TO START WITH.

OTHERWISE...NEXT DISTURBANCES REMAIN PROGNOSTICATED FOR FRIDAY
AND SATURDAY. THE 00Z MODEL GUIDANCE CONTINUES TO SHOW SIZABLE
DISAGREEMENTS ON PLACEMENT...ORIENTATION...AND TIMING OF THESE.
IF SATURATION IS ABLE TO HAPPEN...THE MN PORTION OF THE FORECAST
AREA WILL BE FAVORED FOR SOME SNOW BY BOTH WAVES. BUT BOTH ARE
FAIRLY QUICK MOVING AND THE FIRST IS SHEARING OUT WITH FOCUSED BUT
WEAK ASCENT. SO HAVE MADE LITTLE CHANGES TO THE SMALL POPS FOR THU
NIGHT INTO FRI AS THEY CONTINUE LOOKING GOOD WITH THIS PATTERN AND
THE LATEST GUIDANCE. FOR SAT...HAVE FURTHER INCREASED POPS OVER
MUCH OF THE MN FORECAST AREA AS THE WELL DEVELOPED POTENTIAL
VORTICITY LOBE TAKES A SIMILAR PATH TO THE ONE THIS PAST
MONDAY...JUST A LOT QUICKER MOVING AND NOT AS DEEP. BEHIND
THIS...SETUP FAVORS SLIGHTLY BELOW NORMAL TEMPERATURES INTO NEXT
WEEK...WHICH IS SUPPORTED BY THE CPC 8 TO 14 DAY OUTLOOK AND 00Z
NAEFS PROBABILISTIC GUIDANCE.

&&

.AVIATION.../12Z TAF ISSUANCE/

NLY TRAJECTORIES STREAMING OFF LK SUPERIOR WL CONT TO BRNG MVFR CIGS
INTO KEAU INTO THE AFTN HRS.  W EDGE OF THESE CLDS HAS RMND FAIRLY
STNRY LAST FEW HRS...BUT MAY CLIP KRNH...SO CARRIED SCT015 TIL 15Z.
METARS AND 11-3.9 SATL SHWG THIN...BUT VERY LOW STRATUS IN EXT W MN
VCNTY COLD SFC HIGH PRES. THESE SHUD RMN W OF RWF/AXN...AND EAST
EDGE OF THESE CLDS SHUD BGN TO THIN OUT AFT SR.  THREAT STRATUS/FOG
DVLPG MANINLY E MN INTO WI COMING NIGHT AS COLD SFC RIDGE MVS IN.
FOR NOW JUST INTRO SCT SC AND MVFR VSBYS.

KMSP...LIGHT NLY WNDS TDY AHEAD OF APRCHG NARROW AXIS OF HI PRES.
WNDS BCMG VRBL THIS EVE BFR COMING LGT SE LT IN TAF PRD.  SOME
THREAT OF STRATUS/FOG DVLPG COMING NITE UNDER COLD HIGH PRES.

&&

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

$$

MTF/BAP