AREA FORECAST DISCUSSION

 
 FXUS65 KMSO 160611
 AFDMSO
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE MISSOULA MT
 1211 AM MDT MON MAR 16 2009
 
 .UPDATE...UPDATED TO DROP THE WIND ADVISORY AND SNOW ADVISORY OVER
 NORTHWEST MONTANA.
 
 
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 .DISCUSSION...THE FRONT HAS PUSHED SOUTH OF KALISPELL AND THE
 WINDS AND SNOWFALL HAS DECREASED.
 
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 .PREV DISCUSSION... /ISSUED 912 PM MDT SUN MAR 15 2009/ 
 
 ..STRONG GUSTY WINDS REGION WIDE TONIGHT...
 
 DISCUSSION...A STRONG COLD FRONT IS MOVING THROUGH NORTH CENTRAL
 IDAHO AND WEST CENTRAL MONTANA THIS EVENING...HAVING JUST PASSED
 THROUGH THE MISSOULA AREA OVER THE LAST HOUR. MODERATE TO HEAVY
 SNOW WILL OCCUR ALONG AND NEAR THE COLD FRONT ABOVE 4500 FEET AS
 IT SAGS SOUTHWARD TOWARD SOUTHWEST MONTANA AND LEMHI COUNTY BY
 DAYBREAK MONDAY. VERY STRONG GUSTY WINDS ARE BEING SEEN AHEAD
 OF...ALONG AND BEHIND THE FRONT. THE ATMOSPHERE IS UNSTABLE...AND
 STRONG WINDS ALOFT ARE BEING MIXED TO THE SURFACE AS AN ASSOCIATED
 140 KNOT JET STREAM PUNCHES INTO THE REGION OVERNIGHT. A WIND
 ADVISORY HAS BEEN ISSUED FOR PORTIONS OF NORTHWEST MT THIS
 EVENING. THE COLD FRONT WILL STALL OVER LEMHI COUNTY MONDAY AND
 MONDAY NIGHT WITH ACCUMULATING SNOWS SEEN ABOVE 5000 FEET. HENCE A
 WINTER WEATHER ADVISORY HAS BEEN ISSUED FOR SNOW AND BLOWING SNOW
 IN EASTERN LEMHI COUNTY IN THIS TIME FRAME. 
 
 AVIATION...A STRONG COLD FRONT CURRENTLY EXTENDS FROM JUST NORTH
 OF HIGHWAY 200 ALONG THE CONTINENTAL DIVIDE SOUTHWEST THROUGH THE
 BITTERROOT VALLEY BACK TOWARDS GRANGEVILLE...IDAHO. THE FRONT WILL
 SLOWLY MOVE SOUTHEAST THROUGH THE REMAINDER OF THIS EVENING. GUSTY
 SOUTHWEST WINDS CAN BE EXPECTED SOUTH OF THE FRONTAL BOUNDARY.
 ALONG THE FRONT LIGHT TO MODERATE PRECIPITATION WILL FALL AS RAIN
 IN THE WARMER VALLEYS AND SNOW IN THE MOUNTAINS. MOUNTAINS AND
 PASSES WILL BE OBSCURED BY CLOUDS AND PRECIPITATION ALONG THE
 FRONT WHICH IS EXPECTED TO STALL OVER SOUTHWEST MONTANA AND
 CENTRAL IDAHO THIS EVENING. BEHIND THE FRONT VERY GUSTY WINDS
 WILL MIX TO THE SURFACE AND IMPACT KGPI AND MUCH OF NORTHWEST
 MONTANA THROUGH MIDNIGHT.
 
 PREV DISCUSSION... /ISSUED 238 PM MDT SUN MAR 15 2009/ 
 
 DISCUSSION...A MOIST PACIFIC STORM CONTINUES TO MOVE INTO THE
 NORTHERN ROCKIES. THE ASSOCIATED COLD FRONT IS STILL MOVING
 THROUGH THE PACIFIC NORTHWEST...AND THE WARM AIR AHEAD OF THIS
 FEATURE HAS PUSHED SNOW LEVELS INTO THE MOUNTAINS IN MOST OF THE
 REGION. THEREFORE...HAVE RESTRICTED THE REMAINING ADVISORIES TO
 THE MOUNTAINS AND HIGHER VALLEYS. 
 
 SOUTHERLY WINDS HAVE ALSO INCREASED STEADILY AHEAD OF THE FRONT.
 MANY AREAS ARE SEEING WINDS OF 20 TO 30 MPH...BUT THE GRANGEVILLE
 AREA WILL SEE GUSTS INTO THE UPPER 40S THROUGH MID EVENING WHEN
 THE FRONT PASSES THAT AREA.
 
 THE FRONT WILL PUSH THROUGH THE PANHANDLE AND NORTHWEST MONTANA
 LATE THIS EVENING. PRECIPITATION SHOULD DECREASE MARKEDLY IN THOSE
 AREAS AFTER THAT. HOWEVER...MOUNTAIN SNOW WILL CONTINUE THROUGH
 THE NIGHT FROM NORTH CENTRAL IDAHO THROUGH THE CONTINENTAL DIVIDE
 AS THE FRONT AND AN UPPER JET STALL OVER THE AREA. WILL THEREFORE
 LINGER WINTER HIGHLIGHTS IN THOSE AREAS AS WELL...PRIMARILY FOR
 TRAVEL OVER THE PASSES.
 
 ON MONDAY...THE JET/SURFACE FRONT WILL SAG SOUTHWARD SOMEWHAT WITH THE
 FOCUS FOR SNOW BEING THE HIGHER TERRAIN IN LEMHI COUNTY IDAHO AND
 SOUTHWEST MONTANA. THIS TERRAIN COULD ALSO EXPERIENCE TRAVEL
 DIFFICULTIES AT TIMES WITH THESE FEATURES.
 
 TUESDAY THROUGH SUNDAY...MODEL GUIDANCE CONTINUES TO SHOW A ZONAL
 WESTERLY UPPER LEVEL PATTERN OVER THE PACIFIC NORTHWEST INTO THE
 END OF THE WEEK. A PACIFIC MOISTURE FEED WILL ACCOMPANY THIS
 PATTERN THROUGH THIS TIME FRAME AND MOUNTAIN SNOW SHOWERS WILL BE
 POSSIBLE THROUGH THURSDAY. AT CURRENT TIME THERE DOES NOT APPEAR
 TO BE ANY STRONG OR IMPRESSIVE FEATURE WITH THE CURRENT PATTERN
 THAT WOULD CAUSE MORE THAN NUISANCE IMPACTS THROUGHOUT THE
 REGION...INCLUDING MOUNTAIN PASSES...UNTIL POSSIBLY THE MIDDLE OF
 THE COMING WEEKEND.
 
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 .MSO WATCHES/WARNINGS/ADVISORIES...
 MT...WINTER WEATHER ADVISORY UNTIL 6 PM MDT THIS EVENING FOR 
      BITTERROOT/SAPPHIRE MOUNTAINS.
 
      WINTER STORM WARNING UNTIL 6 AM MDT EARLY THIS MORNING FOR WEST 
      GLACIER REGION.
 
 ID...WINTER WEATHER ADVISORY UNTIL 5 PM PDT MONDAY FOR SOUTHERN 
      CLEARWATER MOUNTAINS.
 
      WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT MDT 
      TONIGHT FOR EASTERN LEMHI COUNTY.
 
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 $$
 
 SHORT TERM...KOLATA
 LONG TERM/AVIATION...FELSCH