FXUS65 KTFX 021733
AFDTFX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
1045 AM MST WED DEC 2 2009
.UPDATE...
AN AREA OF CLOUDINESS IS AFFECTING THE EASTERN PLAINS ZONES AND
RADAR IS INDICATING THERE COULD BE A LITTLE LIGHT SNOW COMING OUT
OF THE CLOUDS. WILL MAKE SOME MINOR ADJUSTMENTS TO SKY COVER
FORECASTS AND SNOW FORECASTS BASED ON RADAR/SATELLITE IMAGERY.
THE OTHER CHANGE WAS TO LOWER SOME HIGH TEMPERATURES FOR
TODAY MAINLY IN THE SOUTHWEST VALLEYS. BLANK
&&
.AVIATION...
UPDATED 1745Z.
EXPECT VFR CONDITIONS. CEILINGS NEAR 5000 FT WILL AFFECT
KHVR/KLWT/KBZN/KGTF THROUGH THIS AFTERNOON/EARLY EVENING. THERE
ALSO COULD BE A FEW SNOW FLURRIES AT KLWT AND KHVR BUT AM NOT
LOOKING FOR ANY MVFR CEILINGS OR VISIBILITIES. FEEL PRETTY GOOD
ABOUT SKIES CLEARING OVERNIGHT. BLANK
&&
.PREV DISCUSSION...
/ISSUED 445 AM MST WED DEC 2 2009/
TODAY THROUGH FRIDAY...AN UPPER LEVEL HIGH PRESSURE RIDGE HAS
BUILT OVER THE WEST COAST. THIS WILL PLACE THE ZONES UNDERNEATH
NORTH FLOW ALOFT. A LOW PRESSURE CENTER WILL BE OVER CENTRAL
CANADA AND MOISTURE ASSOCIATED WITH THIS SYSTEM SHOULD CLIP THE
EASTERN ZONES....AND MOVE INTO THE CENTRAL ZONES BY EVENING.
INCREASED SKY COVER...AND PERHAPS A FLURRY OR TWO OVER THE EASTERN
ZONES...WILL BE THE ONLY EFFECTS. OTHERWISE...THE AIRMASS WILL
STAY DRY THROUGH FRIDAY. AT LOWER LEVELS...SURFACE HIGH PRESSURE
WILL KEEP SURFACE WINDS LIGHT TODAY. THE UPPER LEVEL RIDGE WILL
FINALLY MOVE OVER THE ROCKIES BUT WARMING OF THE AIRMASS WILL BE
MARGINAL AS A SHORTWAVE QUICKLY MOVES INTO THE RIDGE AND OVER THE
ROCKIES BY MID DAY FRIDAY. ZELZER
FRIDAY NIGHT THROUGH MONDAY NIGHT...A RATHER VERY COLD AND WINTRY
WEATHER PATTERN SETTING UP OVER THE WEEKEND AND INTO EARLY NEXT
WEEK. BOTH THE EC/GFS MODELS CONTINUE TO INDICATE SOME FAIRLY COLD
AIR TO MOVE INTO THE REGION OVER THE WEEKEND...AND THEN CONTINUE TO
RESIDE OVER THE REGION FOR SEVERAL DAYS. AS THE COLD FRONT MOVES
THROUGH LATE FRIDAY NIGHT AND THROUGH THE DAY ON SATURDAY...EXPECT
ANOTHER ROUND OF LIGHT SNOW TO ACCOMPANY THE FRONTAL PASSAGE. SNOW
AMOUNTS AND AREA OF SNOWFALL FOR SATURDAY LOOK TO BE FAIRLY SIMILAR
TO TUESDAY MORNINGS SNOW EVENT...IN WHICH GENERALLY 1 TO 2 INCHES
FELL AT LOWER ELEVATIONS AND 3 TO 5 INCHES FELL IN THE
MOUNTAINS...WITH LITTLE/NO SNOW FALL EXPECTED IN THE HAVRE AREA AND
NORTHEAST OF LEWISTOWN. AFTER THIS COLD FRONT MOVES
THROUGH...MODIFIED ARCTIC AIR WILL MOVE INTO THE REGION...AND THE
ONLY THING STOPPING WIDESPREAD MORNING TEMPERATURES FROM BEING
AROUND 20 BELOW WILL BE CLOUD COVER. THUS OVERNIGHT LOWS HAVE BEEN
LOWERED A BIT...BUT BECAUSE OF THE EXPECTED CLOUD COVER...ONLY THE
COLDEST LOCATIONS HAVE FORECASTED TEMPERATURES NEAR 20 BELOW RIGHT
NOW...BUT THIS SITUATION WILL NEED TO BE MONITORED CLOSELY OVER THE
NEXT FEW DAYS. THERE WILL BE A FEW ISOLATED SNOW SHOWERS SUNDAY AND
MONDAY...BUT ANY SNOWFALL WILL BE LIGHT. BRUSDA
TUESDAY AND WEDNESDAY...MODELS CONTINUE TO SHOW A COLD UPPER LEVEL
LOW OVER CENTRAL CANADA...BRINGING COLD ARCTIC AIR INTO THE REGION
UNDER A NORTHERLY FLOW ALOFT. TEMPERATURES WILL CONTINUE TO BE WELL
BELOW AVERAGE WITH ISOLATED SNOW SHOWERS. WILLIAMSON DC
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 19 2 23 6 / 0 0 0 10
CTB 17 -1 25 4 / 0 0 0 10
HLN 22 12 26 7 / 0 0 0 10
BZN 19 -6 20 -7 / 10 10 0 0
WEY 14 -14 14 -7 / 10 10 10 10
DLN 20 0 20 2 / 0 0 0 0
HVR 23 2 23 1 / 10 0 0 10
LWT 17 -7 18 -1 / 10 10 0 10
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BLANK
LONG TERM...MLS
AVIATION...MLS
WEATHER.GOV/GREATFALLS
