FXUS65 KMSO 042139
AFDMSO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
239 PM MST SAT FEB 4 2012

.DISCUSSION...HIGH PRESSURE WILL PERSIST OVER THE NORTHERN
ROCKIEST THROUGH SUNDAY NIGHT AND BRING VERY STABLE AND DRY
CONDITIONS.

TEMPERATURES OVERNIGHT TONIGHT AND SUNDAY WILL BE CHALLENGING IN
SOME AREAS. LITTLE CHANGE IN TEMPERATURES (IN THE MID 20S) ARE
EXPECTED IN THE FLATHEAD/MISSION VALLEYS WHERE A PERSISTENT LOW
STRATUS DECK IS EXPECTED THROUGH SUNDAY NIGHT. OTHER AREAS WILL
SEE A DECENT DROP IN OVERNIGHT LOWS INTO THE LOW TEENS AND AROUND
0 IN THE BUTTE REGION. HOWEVER IF A LOW STRATUS DECK OR PATCHY FOG
DEVELOPS EARLY THEN OVERNIGHT LOWS WILL NOT DROP AS MUCH.

AS MENTIONED A LARGE AREA OF LOW STRATUS CLOUDS (BASE OF ABOUT
1000 FEET) DEVELOPED LAST NIGHT IN THE FLATHEAD/MISSION VALLEYS.
UNTIL A PATTERN CHANGE OCCURS MONDAY THESE LOW CLOUDS WILL REMAIN
IN PLACE. SNOW FLURRIES ARE POSSIBLE UNDER THIS LOW STRATUS DECK.

LOW STRATUS WITH SOME PATCHY FREEZING FOG WILL OCCUR AGAIN
TONIGHT IN THE VALLEYS OF FAR NORTHWEST MONTANA, GLACIER NP, THE I-90
CORRIDOR FROM SUPERIOR TO MISSOULA. PATCHY FOG WILL MAKE IT DOWN
TO FLORENCE OVERNIGHT. THESE LOW CLOUDS WILL DISSIPATE BY MID
MORNING IN MISSOULA AND EARLY AFTERNOON IN NORTHWEST MONTANA...GLACIER
NP AND CENTRAL IDAHO. AFTER CLEARING SUNNY CRISP BLUE SKIES WILL
OCCUR.

A WEAK DISTURBANCE WILL BRUSH THE CONTINENTAL DIVIDE MONDAY AND
TUESDAY AND PRODUCE LIGHT SNOW SHOWERS OVER THE MOUNTAINS. ENOUGH
OF A EASTERLY PRESSURE GRADIENT WILL PRODUCE SOME EAST WINDS IN
THE FLATHEAD VALLEY AND HELP TO SCOUR OUT THE LOW STRATUS DECK.

MODELS DIVERGE SIGNIFICANTLY BY MID TO LATE NEXT WEEK SO
CLIMATOLOGY WILL BE USED FOR THE FORECAST.







&&

.AVIATION...STRONG HIGH PRESSURE WILL PERSIST OVER THE REGION
THROUGH SUNDAY NIGHT. LOW STRATUS WILL CONTINUE NIGHT AND DAY IN
THE FLATHEAD/MISSION VALLEYS. EXPECT LOW CEILINGS AND OBSCURED
MOUNTAINS IN THIS REGION AND EFFECT KGPI. EXPECT PATCHY FREEZING
FOG TO IMPACT KMSO AFTER 05/1100Z TONIGHT AND AGAIN SUNDAY NIGHT.
FOG WILL DISSIPATE BY MID MORNING. OTHERWISE CLEAR SKIES AND VFR
CONDITIONS THROUGH SUNDAY NIGHT.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
ID...NONE.
&&

$$

SHORT TERM...RPN
LONG TERM....RPN
AVIATION...RPN



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