376 
FXUS63 KMPX 292034
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
335 PM CDT FRI OCT 29 2004

.DISCUSSION...
EARLY THIS EVE SVR WX THREAT STILL IN PLAY AS CLDS HAVE BROKEN OVER 
ALL BUT FAR N ZONES AND WARM SLY WINDS HAVE PUSHED TEMPS INTO THE 
70S AND DEW PTS IN THE 60S. OF NOTE...66 DEW PT MEASURED AT MPX WAS 
HIGHEST EVER RECORDED THIS LATE IN THE SEASON. OLD DEW PT RECORD WAS 
64. EVEN THOUGH THE CALENDAR SAYS OCT 29...THIS IS A SUMMER LIKE 
SYSTEM. 

MODERATE RISK FOR SVR WX 5-10 PM TIME FRAME...MAINLY OVER ERN HALF 
OF CWA. COLD FRONT ENTERED SW MN ABT 19Z AND WILL BE DRAGGED ENEWARD 
THRU REMAINDER OF ZONES /EXCEPT NW ZONES WHERE LOW WILL TRACK/ THRU 
THE EVENING HRS. AHEAD OF THIS BDRY OVER NRN IA AND FAR S MN SCT 
SUPERCELLS ARE EXPECTED TO DEVELOP AND BE PUSHED NNE ON STRONG LOW 
LVL JET. THESE STORMS HOLD THE HIGHEST TORNADO THREAT.  THERE IS 
ALSO A SMALL THREAT THAT ISOLATED SUPERCELLS COULD GENERATE INVOF 
WARM FRONT...ESPECIALLY OVER NE ZONES WHERE THE SUN HAS BROKEN OUT 
OVER PAST FEW HRS...AND SFC WINDS ARE STILL FROM THE SE. 

IN ADDITION TO SUPERCELL DEVELOPMENT AHEAD OF FRONT...A LINE OF 
TSTMS WILL FIRE RIGHT ALONG COLD FRONT AND WILL SWING THROUGH CWA 
MAINLY S OF A LINE FROM RWF TO BUFFALO TO TAYLORS FALLS. HIGH WIND 
WILL BE MAJOR THREAT WITH THIS LINE BUT LARGE HAIL IS ALSO POSSIBLE. 
NORTH OF THE WARM FRONT /N OF AFOREMENTIONED LINE/ DEEPENING LOW 
WILL GENERATE ELEVATED CONVECTION THAT COULD DROP LARGE HAIL. AFTER 
COLD FRONT PASSES THRU S AND E CWA A DRY SLOT SHUD GIVE CWA /EXCEPT 
NW WHERE LOW WILL DROP RAIN THRU THE EVE/ A FEW HRS OF DRY WEATHER 
LATE THIS EVE BEFORE THE WRAPAROUND CLDS AND RAIN MOVE IN.     

DID NOT GET A CHANCE TO THOROUGHLY INTERROGATE MODELS FOR SAT THRU 
MON FCST DUE TO SVR WX THREAT TODAY. HOWEVER...A FEW QUICK THINGS TO 
NOTE...VERY STRONG 850MB WINDS FOLLOW EXITING LOW WHICH WILL BRING 
WINDY CONDITIONS TO CWA FROM W TO E STARTING AROUND DAWN W AND MID 
AFT FAR E. WIND ADV MAY BE NEEDED TOMORROW. WILL LET MID CREW DECIDE 
NECESSITY WITH NEW MODEL RUN. WRAPAROUND CLDS WILL LINGER ACROSS 
ZONES INTO SAT NIGHT WHEN THEY WILL QUICKLY PUSH OFF FROM W TO E. 
BEST LIFT EXITS FROM W TO E SATURDAY AFTERNOON SO EXPECTING PRECIP 
TO COME TO AN END WELL BEFORE CLDS EXIT. 

SUNDAY PRETTY QUIET WITH ONLY A VERY WEAK RIPPLE IN THE ATMOS 
PASSING THRU. LATE SUN NIGHT LOW PRES OVER CENT PLAINS WILL PUSH NRN 
PORTION OF RAIN SHIELD VERY CLOSE TO ZONES INTO MON. HAVE CHANCE 
POPS TO COVER ANY ACTION THAT REACHES INTO SRN/ERN ZONES AS LOW 
PASSES TO OUR SE.  

LONGER TERM...TUE THRU FRI
INITIALLY THE GFS PUSHES A TROUGH SOUTH OF OUR AREA WITH NEAR ZONAL 
FLOW TRANSITIONING TO SOUTHWEST FLOW ALOFT THROUGH THURSDAY MORNING. 
GFS BRINGS STRONGEST FORCING TO NEAR (1000-500 MB THICKNESS 
DIFFLUENCE) INTO AREAS WEDNESDAY NIGHT AND EARLY THURDAY AND WE 
CARRY A LOW POP SCENARIO FOR MIXED RAIN AND SNOW. THE COLDEST AIR OF 
THE FOUR DAY PERIOD PUSHES IN FROM CANADA FRIDAY MORNING AS 
THICKNESS DROP TO 528. 

&&

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

&&
$$

MARGRAF/WET