FXUS63 KMPX 011816
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1216 PM CST TUE DEC 1 2009

.UPDATE...

18Z AVIATION DISCUSSION ADDED BELOW.

&&

.DISCUSSION...

DECEMBER BEGINS WITH ONE MORE WELL ABOVE NORMAL DAY AND THUS MAY
BE BETTER ASSOCIATED WITH NOV THAN THIS UPCOMING STRETCH...AS THE
MONTH FINISHED 2ND WARMEST AT MSP AND 3RD AT EAU AND STC. AFTER
TODAY COMES THE FORECAST CHALLENGE...PLUNGING TEMPS AS A COLD
FRONT AND SECONDARY FRONTS MOVE SOUTH THROUGH THE AREA BEGINNING
TONIGHT. OVERALL...THE AREA WILL REMAIN BETWEEN APPRECIABLE PRECIP
THE NEXT 48 TO 72 HOURS...WITH SNOW IN FAR NRN MN TODAY AND
TONIGHT AND A POWERFUL SYSTEM LIFTING UP THE ERN THIRD OF THE
COUNTRY ON WED INTO THU.

THE GOES WATER VAPOR AND LAST EVES RAOB ANALYSIS SHOW A STRONG
UPPER TROUGH DIVING SOUTHEAST FROM WEST CTRL CANADA...WITH H5
TEMPS AT -36C IN ALBERTA. FLOW PATTERN WILL TURN THIS SYSTEM
MOVEMENT MORE ERLY TODAY INTO AND ACROSS NRN MN. TO THE SOUTH OVER
OUR AREA...WE WILL BE WITHIN THE ELEVATED WARM SECTOR WITH OFF
AND ON CLOUD COVER BUT NO PRECIP EXPECTED. TEMPS WILL REALIZE NEAR
40 NORTH TO NEAR 50 SOUTH...10 TO 17 DEGREES ABOVE NORMAL.

THE PRELIMINARY COLD FRONT ASSOCIATED WITH THIS SYSTEM WILL MOVE
INTO WRN MN DURING THE MIDDLE OF THIS AFTERNOON. GUSTY WEST WINDS
WITHIN STEEP LOW LEVEL LAPSE RATES DUE TO THE TIME OF DAY SHOULD
ALLOW FOR 35 MPH GUSTS IN ELEVATED AREAS OF WEST CTRL MN. THESE
MAY LAST MUCH OF THIS EVE GIVEN THE NAM MOMENTUM TRANSFER
PROFILES. A SECONDARY FRONT IS TO DROP DOWN LATE TONIGHT AND WED
MORNING BRINGING H8 TEMPS OF -10C TO -13C INTO THE REGION FOR THE
FIRST TIME THIS COOL SEASON. THIS SHOULD FAVOR WIDESPREAD STRATOCU
BY MIDDAY WED WHICH MAY NOT BREAK UNTIL FRI OR SAT. THROUGH THAT
PERIOD...HAVE LEFT GIVEN FORECAST OF OCCASIONAL SNOW SHOWERS OR
FLURRIES ALONE. THIS FITS THE DEEP CYCLONIC FLOW OFFERING EMBEDDED
PVA MAXS AND COLD POCKETS FOR FAVORABLE LAPSE RATES ACROSS THE
AREA. THESE ARE A BIT MORE FOCUSED DURING THU AND FRI AS MODELS
CONTINUE TO SLOW WITH THE DEEP CYCLONIC FLOW...BUT THESE WAVES
REMAIN DIFFICULT TO PIN DOWN TIMING-WISE. THIS SYSTEM IS LONG-
LASTING IN ITS INFLUENCE DUE TO THE FORECAST UPPER TROUGH OVER ERN
CANADA TRANSLATING LITTLE EAST. THE 00Z GFS AND ECMWF BRING THE
FINAL PRONOUNCED WAVE WITHIN THE TROUGH SOUTH THROUGH THE AREA ON
FRI AND FRI NIGHT. CONTINUE TO END PRECIP CHANCES BY FRI NIGHT IN
THE FORECAST. SO ANY SNOWFALL ACCUMS THAT OCCUR FROM WED TO FRI WILL
BE MINOR /UNDER 1 IN/ DUE TO LIMITED FORCING AND SHOWERY NATURE OF
THE SNOW.

TEMPS WILL DROP TO BELOW NORMAL DURING THE LATTER HALF OF THE
WEEK. WITH A SLOWER PATTERN AND LASTING CLOUDS...HAVE MINIMIZED THE
TEMPERATURE RANGE EVEN MORE...BRINGING LOWS UP A FEW DEGREES AND
HIGHS DOWN A COUPLE MORE DEGREES. THERE STILL BE SOME SINGLE
DIGITS IN WRN MN THU AND FRI NIGHTS...POSSIBLY ACROSS MUCH OF THE
OUTLYING MN FORECAST AREA FRI NIGHT OR SAT NIGHT DEPENDING ON
CLOUDS.

&&

.AVIATION.../18Z TAF ISSUANCE/ 

TWO MAIN CONCERNS THIS FORECAST PERIOD ARE POTENTIAL ONSET OF MVFR
CIGS THIS AFTERNOON/TONIGHT AND WINDS. CULPRIT FOR ALL OF THIS IS
CLIPPER SYSTEM ZIPPING ACROSS NORTH CENTRAL MN THIS AFTERNOON.
MAIN COLD FRONT IS JUST NOW ON THE DOORSTEP OF RWF/AXN...WITH A
WARM FRONT JUST S/SW OF MSP. WILL SEE WINDS TURN FROM SE TO THE
WNW THIS AFTERNOON AT ALL BUT AXN/RWF...WHO ARE BASICALLY ALREADY
THERE. A FROPA A LITTLE BEFORE 00Z AT MSP STILL LOOKS TO BE ON
TRACK. AS FOR GUSTS...PRESSURE CHANGE PATTERN SHOWS BEST FORCING
FOR GUSTS GOING NORTH OF AREA...SO DIALED BACK ON SPEEDS
SOME...BUT BASED ON OBS ACROSS THE DAKOTAS...STILL LOOKS GOOD FOR
A FEW HOURS OF GUSTS AFTER FROPA. AS FOR CLOUDS...MAV/MET/GFSLAMP
GUIDANCE ALL NOT IN TUNE WITH WHAT PARENT MODELS SHOW FOR THE
STRATOCU OFF TO THE NORTH. AT MSP...MET IS ONLY GUIDANCE BRINGING
IN MVFR CIGS...BUT NOT UNTIL 12Z. SO...STUCK CLOSE TO WHAT RUC AND
NAM/GFS MODEL OUTPUT HAVE FOR CLOUDS. THIS WOULD RESULT IN THE
STRATOCU SURGING SOUTH SHORTLY AFTER 00Z AS FIST BLAST OF CAA SETS
IN. BASED ON UPSTREAM OBS...IF THE CLOUDS DO ROLL IN...SHOULD
EVENTUALLY SETTLE IN THE 015-020 RANGE BEFORE HEADING BACK TOWARD
030 BY WEDNESDAY AFTERNOON. SOME CONCERN THIS MAY NOT HAPPEN BASED
ON SHALLOWNESS OF MOISTURE AND SINKING MOTION COMING IN BEHIND THE
CLIPPER...BUT CLIMATOLOGY WITH A SYSTEM LIKE THIS CERTAINLY FAVORS
A MORE PESSIMISTIC FORECAST THAN GUIDANCE WOULD SUGGEST.

&&

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

$$

MTF/MPG