FXUS63 KFGF 010947
AFDFGF
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
345 AM CST TUE DEC 01 2009
...WINTER WEATHER ADVISORY TODAY MAINLY ALONG AND NORTH OF U.S.
HIGHWAY 2...
.DISCUSSION...
AT 08Z... SURFACE LOW PRESSURE HAD DUG INTO NWRN ND NEAR KPAR...AND
APPEARS ON TRACK TO AFFECT MICH OF NERN ND AND NWRN MN THROUGHOUT
THE DAY TODAY. MODEL GUIDANCE HAS REFUSED TO LOCK ONTO A COHERENT
SOLUTION THROUGH 06Z THOUGH ENSEMBLE MEAN PATH WOULD TAKE THE SFC
LOW PAST HILLSBORO BY NOON AND WELL PAST DLH LATER THIS EVENING.
TODAY... RADAR SHOWS THE MOISTENING MID LEVEL CLOUD BAND WHICH HAS
BEGUN TO SET UP IN A BAND FROM ESTEVAN...THROUGH PILOT MOUND...AND
EASTWARD PAST HALLOCK TO WASKISH. SOME LIGHT SNOW HAS BEEN REPORTED
ALONG THIS BAND BUT PRECIP SHOULD INTENSIFY AS THE SFC LOW DIGS EWD.
HEAVIEST SNOW IS EXPECTED MAINLY ALG AND NORTH OF HWY 2...WHERE
FRONTOGENETICAL FORCING IS STRONGEST AND CONDENSATION PRESSURE
DEFICTS LEAST. MODERATELY STRONG NORTH WINDS ARE EXPECTED TO DEVELOP
BEHIND THE LOW AND CAUSE REDUCED VISIBILITIES IN BLOWING SNOW.
MODERATELY STRONG WINDS ARE ALSO EXPECTED FROM MID AFTERNOON INTO
EARLY EVENING ACROSS SERN ND INTO WCNTRL MN...BUT WITH SUBSTANTIALLY
LESS SNOW OR REDUCTIONS IN VISIBILITY DUE TO BLOWING SNOW.
TONIGHT... WRAPAROUND CLOUDS...SNOW SHOWERS AND NORTHERLY WINDS WILL
LIKELY CONTINUE WELL INTO THE EVENING. WITH SUCH A FAST MOVING
SYSTEM... SNOWFALL WILL TAPPER OFF FAIRLY RAPIDLY AFTER PASSAGE OF
THE LOW. TEMPERATURES WILL STEADILY COOL THROUGH THE MIDWEEK PERIOD
AND DROP BELOW SEASONAL NORMALS BY WEDNESDAY.
WEDNESDAY AND THURSDAY... WRAPAROUND CYCLONIC FLOW PERSISTS OVER OUR
AREA THROUGH MIDWEEK AS THE POLAR VORTEX INTENSIFIES OVR HUDSONS BAY
AND A SECOND WEEK LOW PRESSURE SYSTEM DROPS SOUTHWARD FROM MANITOBA
INTO THE DKTAS. EPISODES OF LIGHT SNOW OR FLURRIES ARE EXPECTED
THOUGH PRECIP AMOUNTS SHOUL BE MINIMAL.
&&
.AVIATION...
MAINLY HIGH CLOUDS AND LIGHT WINDS WILL AFFECT THE SRN FA THROUGH
THE MORNING WHILE VFR CIGS...LIGHT SNOW AND INCREASING EASTERLY FLOW
BUILDS OVER THE NRN FA. BY 18Z...SFC LOW PRESSURE CENTER SHOULD PASS
JUST SOUTH OF A GFK-FSE LINE...WITH MVFR CIGSAND VSBYS...MODERATE
SNOW AND INCREASING NORTHERLY FLOW NORTH. AFT 18Z...MVFR CIGS AND
VSBYS SHOULD SPREAD SOUTHWARD THROUGH ERN ND TO VCNTY FAR AND
CONTINUE SPREADING EWD INTO NCNTRL MN. NORTHWEST WINDS OF 20G35KTS
WILL INCREASE AFT 18Z AND SPREAD EWD FROM ERN ND INTO NWRN MN.
&&
LONG TERM [THU NIGHT - SUN]...
THE MAIN CHALLENGES IN THE LONG TERM ARE PCPN CHANCES THIS WEEKEND
AND DAILY TEMPERATURES. THERE ARE STILL CONSIDERABLE DIFFERENCES
BETWEEN THE MODELS...MAINLY STEMMING FROM THE HANDLING OF TROUGH
ALONG THE CANADIAN PACIFIC COAST THU AND FRI. THE GFS AND DGEX
CONTINUE TO INDICATE THE TROUGH WILL DIG DEEPER AND INTO THE HIGH
PLAINS...WHICH WOULD INDICATE SLIGHTLY BETTER CHANCES OF PCPN THAN
THE ECMWF AND GEM. THE ECMWF AND GEM CONTINUE TO INDICATE LESS
TROUGHING WITH A CUTOFF LOW NEAR THE AMERICAN NW COAST. LEANED TO
THE DRY ECMWF AND GEM. WHAT SEEMS TO BE MORE CERTAIN ARE COLDER
TEMPERATURES LATE THIS WEEK AND INTO THE WEEKEND...WITH HIGHS
GENERALLY IN THE 20S AND UPPER TEENS. BOTH THE GFS AND ECMWF ARE
HINTING AT AN INFLUX OF ARCTIC AIR EARLY OR DURING THE MIDDLE OF
NEXT WORK WEEK...SO OVERNIGHT LOWS NEAR 0 DEGREES ARE POSSIBLE
NEXT MON AND TUE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WINTER WEATHER ADVISORY TODAY FOR NDZ006>008-014>016-24>27-054.
MN...WINTER WEATHER ADVISORY TODAY FOR MNZ001-004>009-013>017.
&&
$$
GUST
