000
FXUS63 KFGF 032047
AFDFGF
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
247 PM CST WED DEC 3 2008
.SHORT TERM...
FORECAST CHALLENGE WILL BE SEVERAL CHANCES FOR LIGHT SNOW...ONE
TONIGHT AND THE NEXT LATER FRI INTO FRI NIGHT. 12Z MODELS HAVE
COME INTO BETTER AGREEMENT WITH THE SECOND SYSTEM...WITH THE
EXCEPTION OF THE NAM. WILL USE THE GFS TODAY WHICH MATCHES WELL
WITH THE EUROPEAN SOLUTIONS AND CONTINUITY.
TONIGHT...APPEARS THERE ARE MULTIPLE WEAK PIECES OF ENERGY
DROPPING SOUTH IN THE OVERALL CYCLONIC 500MB FLOW PATTERN OVER THE
NORTHERN PLAINS. ONE SHOT OF LIGHT SNOW IS DROPPING THRU THE
WESTERN AND CENTRAL DAKOTAS NOW WITH THE REGIONAL RADAR LOOP
SHOWING THE STRONGEST ECHOES AROUND THE KBIS AREA NOW. 20Z KBIS
OBSERVATION SHOWS THE VSBY DOWN TO AROUND 2 MILES. THIS MOVED THRU
KMOT EARLIER AND MAY YET GLANCE OUR WEST/SW FA INTO THE EARLY
EVENING. STILL A DECENT KINK IN THE 500MB FLOW DROPPING TOWARD
SOUTHERN SASKATCHEWAN AND SOUTHERN MANITOBA. THIS IS ALSO
PRODUCING SOME LIGHT SNOW OR FLURRIES...WHICH COULD LINGER ACROSS
THE FA LATER TONIGHT. THICKER CLOUD COVER HAS TAKEN A LONG TIME TO
MOVE TOWARD THE FA TODAY...BUT NOW APPEARS TO BE ESTABLISHED WEST
OF A LINE FROM KJMS TO CYWG. THESE CLOUDS SHOULD CONTINUE TO
THICKEN ACROSS THE ENTIRE FA TONIGHT. THIS CLOUD COVER SHOULD HELP
PREVENT TEMPS FROM FALLING OFF TOO FAR TONIGHT.
THU-THU NIGHT...PRETTY COLD AIR ALOFT WILL CROSS THE FA THU...SO
IF THERE ARE ANY HOLES IN THE CLOUDS THEY SHOULD FILL BACK IN.
ALONG WITH THE CLOUDS THERE AGAIN COULD BE SOME LINGERING LIGHT
SNOW OR FLURRIES THRU THE DAY. WILL KEEP THU NIGHT DRY...ALTHOUGH
THE MODELS ARE TRYING TO LINGER SOME FLURRIES OVER NORTHWEST MN.
FRI-SAT...SHOULD STILL BE RATHER QUIET FRI MORNING...PRIOR TO THE
NEXT CLIPPER SYSTEM FRI AFTERNOON INTO EARLY SATURDAY. MODELS HAVE
BEEN IN DISARRAY WITH THE TIMING AND TRACK OF THIS CLIPPER. THE
GFS HAS BEEN THE MIDDLE OF THE ROAD MODEL...BUT NOW IT HAS SUPPORT
FROM THE EUROPEAN MODELS TOO. NAM CONTINUES TO BE THE OUTLIER...SO
WILL DISREGARD IT FOR THE MOST PART. THIS CLIPPER LOOKS TO DROP
DOWN TOWARD THE NORTHERN RED RIVER VALLEY BY 00Z SAT AND TOWARD
THE WESTERN GREAT LAKES BY 12Z SAT. THIS SYSTEM WILL BE A QUICK
MOVER AND THEREFORE SNOWFALL AMOUNTS WILL BE PRETTY MINIMAL.
CURRENT THOUGHTS MATCH INHERITED FORECAST...WHICH WOULD MAINLY BE
A DUSTING TO AN INCH OR SO. SFC HIGH QUICKLY BUILDS IN BEHIND THIS
CLIPPER BY 00Z SUN.
.LONG TERM...
MAIN CHALLENGE THROUGH LONG RANGE IS TIMING OF SHORT WAVE THROUGH FA
AND SNOW CHANCES. MODELS SPLIT WITH TIMING OF WAVE SUNDAY
NIGHT/MONDAY AS GFS/CANADIAN ABOUT 12 HOURS QUICKER THAN ECMWF/DGEX.
AM HESITANT TO INCREASE POPS TOO MUCH WITH MODEL DIFFERENCES BUT
WILL NEED TO SOMETIME ONCE TIMING IS BETTER AGREED UPON. PCPN PHASE
ALSO A QUESTION IN WARM ADVECTION ZONE AHEAD OF LOW AND ALSO WILL
NEED TO BE MONITORED CLOSELY AS SOME FREEZING PCPN POSSIBLE. WITH FA
IN MID LEVEL TROUGH THROUGH MUCH OF THE PERIOD EXPECT TEMPERATURES
TO RANGE AT OR BLO SEASONAL AVERAGES.
&&
.AVIATION...
SOME SPOTTY MVFR CIGS PRIMARILY OVER NW MN A RESULT OF LOW
CONVECTIVE TEMPERATURES AND SHALLOW MOIST LAYER SHOULD DISSIPATE
SOMEWHAT AFTER SUNSET. FARTHER WEST MVFR CIGS AND LOCALLY MVFR VSBY
IN -SN ASSOCIATED WITH DESCENDING SHORTWAVE MAY CLIP WEST HALF OF FA
THIS EVENING INTO THE OVERNIGHT.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
GODON/VOELKER
