Wind Advisory 15, NWS Missoula, MT

000 
WWUS75 KMSO 291428
NPWMSO

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE MISSOULA MT
828 AM MDT TUE SEP 29 2009

IDZ006-009-010-MTZ006-291530-
/O.CAN.KMSO.WI.Y.0015.000000T0000Z-090929T2100Z/
SOUTHERN CLEARWATER MOUNTAINS-WESTERN LEMHI COUNTY-
EASTERN LEMHI COUNTY-BITTERROOT/SAPPHIRE MOUNTAINS-
828 AM MDT TUE SEP 29 2009 /728 AM PDT TUE SEP 29 2009/

...WIND ADVISORY IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS CANCELLED THE WIND
ADVISORY. 

SOUTHWEST WINDS HAVE DIMINISHED SOMEWHAT IN THE HIGHER TERRAIN ACROSS
NORTH CENTRAL IDAHO AND THE BITTERROOT MOUNTAINS THIS MORNING.
THEY WILL CONTINUE TO BE BREEZY THROUGH THE DAY...GENERALLY 15 TO
30 MPH...BUT THIS IS BELOW ADVISORY LEVELS.

$$

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE MISSOULA MT
417 AM MDT TUE SEP 29 2009

.DISCUSSION...THE FIRST SIGNS OF A CHANGING WEATHER PATTERN
WILL OCCUR THIS MORNING AS A COLD FRONT CONTINUES ITS WAY ACROSS THE
NORTHERN ROCKIES. NORTHWEST MONTANA HAS ALREADY UNDERGONE THIS
INITIAL PUSH OF THE FRONT...WITH THE FRONT EXPECTED TO CROSS WEST
CENTRAL MONTANA AND CENTRAL IDAHO LATER THIS MORNING...AND FINALLY
CROSS SOUTHWEST MONTANA BY THIS AFTERNOON. HERE IS WHERE THE FRONT
WILL BECOME SLIGHTLY HUNG UP...THUS FOCUSING THE STRONGEST WINDS
ASSOCIATED WITH THIS FRONT TO OCCUR IN AND AROUND THE
BUTTE/BLACKFOOT REGION AS WELL AS THROUGH LEMHI COUNTY IN IDAHO
THROUGH LATE THIS AFTERNOON. WHILE THE FRONT LOOKS PRETTY
DRY...THE BEST CHANCE FOR PRECIPITATION WILL OCCUR IN THE
AFOREMENTIONED LOCATIONS THIS EVENING AS THE DEEPENING TROUGH OF
LOW PRESSURE WORKS ITS WAY INTO THE AREA AND BECOMES MORE
ORGANIZED. ONCE THINGS GET GOING THEY ARE LIKELY TO CONTINUE
THROUGHOUT OVERNIGHT AS THE TROUGH PUSHES EAST.

COLDER AIR BEHIND THE SYSTEM WILL SPREAD ACROSS NORTHWEST MONTANA
AND WORK ITS WAY SOUTH AND EAST THROUGHOUT THE NIGHT AND INTO
WEDNESDAY MORNING...WITH SNOW LEVELS LOWERING BELOW 6000 FEET DURING
THIS TIME FRAME. WHILE THERE IS STILL SOME UNCERTAINTY AS TO THE
TIMING OF THE COLD AIR IN CONJUNCTION WITH THE DEVELOPING AREA OF
PRECIPITATION...IT IS VERY POSSIBLE THAT THE HIGHER TERRAIN COULD
SEE 1 TO 4 INCHES OF SNOW BY WEDNESDAY AFTERNOON. A LOT WILL
DEPEND ON WHETHER THE COLD AIR CAN TIME ITSELF WITH THE
PRECIPITATION IN ORDER TO CREATE THESE AMOUNTS. A HAZARDOUS
WEATHER OUTLOOK HAS BEEN CONTINUED TO ACCOUNT FOR THIS POTENTIAL.
STAY TUNED TO CHANGES IN THE FORECAST AND ANY UPDATES MADE AS MORE
DETAILS ARE OBTAINED.

THURSDAY THROUGH MONDAY...MODEL GUIDANCE HAS COME INTO BETTER AGREEMENT
WITH A QUICK SHORTWAVE RIDGE PASSING THROUGH THE NORTHERN ROCKIES
THURSDAY INTO FRIDAY. THIS WILL BRING A BRIEF PERIOD OF DRYING.
AFTER THIS WEAK HIGH PRESSURE PASSAGE A LOW PRESSURE SYSTEM LOOKS
TO PUSH INTO THE REGION FROM BRITISH COLUMBIA. SPECIFIC DETAILS
WITH THIS SYSTEM ARE STILL UNSETTLED...BUT A CONTINUATION OF A
COOLER AND MOIST WEATHER PATTERN LOOKS LIKELY THROUGH COMING
WEEKEND. BY MONDAY THE AREA OF LOW PRESSURE WILL BE SHIFTING TO
THE EAST WITH A NORTHERLY FLOW SETTING UP INTO WESTERN MONTANA AND
NORTH CENTRAL IDAHO.

&&

.AVIATION...AN UPPER LEVEL TROUGH AND SURFACE COLD FRONT WILL PUSH
ACROSS THE REGION TODAY. WINDS WILL SHIFT TO WEST BEHIND THE
FRONT. SHOWERS WILL OCCUR WITH AND BEHIND THE FRONT...AND OBSCURE
THE HIGHER TERRAIN.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...FIRE WEATHER WATCH FROM 2 PM MDT THIS AFTERNOON THROUGH THIS
     EVENING FOR DEERLODGE/WEST BEAVERHEAD-EAST BEAVERHEAD.

ID...NONE.
&&

SHORT TERM...ALLEGRETTO
LONG TERM....KOLATA
AVIATION...KOLATA

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MISSOULA MT
411 AM MDT TUE SEP 29 2009

IDZ009-010-MTZ006-007-292215-
WESTERN LEMHI COUNTY-EASTERN LEMHI COUNTY-
BITTERROOT/SAPPHIRE MOUNTAINS-BUTTE/BLACKFOOT REGION-
411 AM MDT TUE SEP 29 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL
IDAHO AND WEST CENTRAL MONTANA.

.DAY ONE...TODAY AND TONIGHT

A VIGOROUS PACIFIC COLD FRONT AND SURGE OF MOISTURE IS EXPECTED
TO SHIFT ACROSS THE AREA THIS EVENING AND TONIGHT. THIS EVENING
THE PRECIPITATION WILL BEGIN AS RAIN AT ALL ELEVATIONS. THEN...AS
COLDER AIR MOVES IN BEHIND THE FRONT OVERNIGHT THE PRECIPITATION
WILL TRANSITION TO SNOW AT THE HIGHER ELEVATIONS.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

BY WEDNESDAY MORNING THE SNOW LEVEL IS EXPECTED TO BE DOWN TO
AROUND 6000 FEET. THE MAIN IMPACT AREA SHOULD BE FROM ROUGHLY LOST
TRAIL PASS EAST AND NORTHEASTWARD TO GEORGETOWN LAKE AND THE
HIGHER TERRAIN AROUND BUTTE. 1 TO 4 INCHES OF SNOW IS
POSSIBLE. HOWEVER...STAY TUNED TO THE LATEST FORECAST AS THERE
REMAINS SIGNIFICANT UNCERTAINTY IN THE AMOUNT OF PRECIPITATION
AFTER THE COLDER AIR ARRIVES.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.