High Wind in Montana, January 22, 2004

SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE GREAT FALLS MT
850 AM MST THU JAN 22 2004

.DISCUSSION...UPDATE TO ZONES PLANNED BY 930...

TODAY...SURFACE LOW PRESSURE IS ACROSS ALBERTA AND HIGH PRESSURE IS
WEST OF THE DIVIDE. THIS IS KEEPING MODERATE DOWNSLOPE CONDITIONS
ACROSS THE LEE OF THE NORTHERN ROCKIES. WINDS SHOULD CONTINUE AND
PERHAPS INCREASE THIS AFTERNOON WITH THE APPROACH OF A WEAK
DISTURBANCE ALOFT. WINDS NEAR THE DIVIDE AND IN PASSES HAS REQUIRED
A HIGH WIND WARNING. AN UPPER LEVEL HIGH PRESSURE RIDGE IS OVER THE
WEST COAST WITH MODERATE NW FLOW ALOFT OVER THE ZONES. MOISTURE IS
MOVING OVER THE RIDGE AND WILL BE AFFECTING THE NORTHERN ZONES
TODAY. A WEAK CHINOOK ARCH IS ALREADY DEVELOPING. WILL UPDATE MAINLY
TO FRESHEN FIRST PERIOD WORDING. ZELZER

FOR FRIDAY...EXPECT SNOW TO CONTINUE TO FALL OVER THE ROCKY MOUNTAIN
FRONT...AND INCREASE IN COVERAGE OVER SOUTHWEST MONTANA AS THE FLOW
ALOFT BECOMES MORE SOUTHWEST. EXPECT FRIDAY TO BE THE LAST MILD DAY
ACROSS THE REGION.

ON FRIDAY NIGHT...THE ARCTIC COLD FRONT WILL BEGIN TO APPROACH NORTH
CENTRAL MONTANA. EXPECT THE FRONT TO BE NEAR THE US/CANADIAN BORDER
BY 5AM SATURDAY. THE FRONT WILL MAKE ITS WAY SOUTH THROUGH NORTH
CENTRAL MONTANA DURING THE MORNING HOURS. EXPECT THE FRONT TO PUSH
THROUGH SOUTHWEST MONTANA DURING THE AFTERNOON AND EVENING HOURS.
TEMPERATURES WILL FALL RAPIDLY BEHIND THE FRONT. PERIODS OF
WIDESPREAD SNOW WILL DEVELOP BEHIND THE FRONT PER THE GFS. GOOD
NORTHERLY WINDS WILL CONTINUE AT THE SURFACE SATURDAY NIGHT ALLOWING
FOR UPSLOPE SNOW TO CONTINUE. A WINTER WEATHER ADVISORY OR WARNING
IS LIKELY SATURDAY AND SUNDAY FOR MUCH OF NORTH CENTRAL AND
SOUTHWEST MONTANA FOR THIS SNOW EVENT...BUT WE WILL WAIT A FEW MORE
MODEL RUNS TO FINE TUNE THE EXACT TIMING OF THE ARCTIC FRONT AND THE
SNOW AMOUNTS. BRUSDA

SUNDAY THROUGH TUESDAY...SURFACE LOW MOVES THROUGH MONTANA WITH VERY
COLD ARCTIC AIR PUSHING OVER AREA AS UPPER LEVEL TROF MOVES ACROSS
CWA. MODELS CONTINUE TO DISAGREE ON TIMING AND POSITION OF SURFACE
LOW MAKING IT DIFFICULT TO FORECAST POPS AND SNOW AMOUNTS. VERY COLD
AIR WILL KEEP SNOW FLURRIES OVER AREA MONDAY AND TUESDAY. CAMP

TUESDAY NIGHT THROUGH THURSDAY...NO NEW GFS PROGS. HOWEVER...LOOKING
AT THE ECMWF AND LATEST GFS RUNS...INDICATE A VERY COLD PERIOD AS
COLD UPPER LOW REMAIN OVER THE AREA WITH THICKNESS VALUES SUB
480 JUST NORTH OF THE BORDER.  WEAK UPSLOPE FLOW COMBINED WITH UPPER
LOW OVER AREA...WILL GO WITH A CHANCE OF MAINLY MOUNTAIN SNOW OVER
THE SOUTHWEST AND ALONG THE ROCKY MOUNTAIN FRONT TUESDAY NIGHT AND
WEDNESDAY. TEMPERATURES WILL REMAIN VERY COLD ACROSS NORTH CENTRAL
MONTANA AND THE SOUTHWEST VALLEYS WITH SOME MODERATION FOR HIGHER
ELEVATIONS BY THURSDAY...MAINLY OVER THE SOUTHWEST. WILLIAMSON DC

.CCF NUMBERS
GTF NN 048/037 046/026 028 17000
    SIIII 905/902 918/905 923/910 921/905 915 07843220100
CTB NN 046/035 044/020 020 17000
    SIIII 911/907 920/905 924/914 926/906 918 38843220-00
HLN BE 041/030 039/027 033 17000
    SSIII 005/008 000/908 918/906 915/901 915 2685433221-
BZN BE 033/018 032/020 031 17000
    SEEIB 001/009 902/007 913/906 915/002 909 3584333211-
WEY BE 025/008 023/011 022 1700-
    SSIIB 902/004 910/901 918/903 917/021 902 4675222322-
DLN BE 035/018 036/019 030 17002
    SEEIB 006/014 901/012 914/906 909/001 904 5584433321-
HVR EE 041/030 039/016 016 17000
    SIIII 906/905 921/905 921/915 923/909 918 28742220000
LWT EE 042/031 041/024 026 17000
    SEIII 902/000 911/903 914/913 918/901 912 05842220100

.TFX...WINTER STORM WARNING TONIGHT THROUGH EARLY SATURDAY MORNING
       FOR THE ROCKY MOUNTAIN FRONT ABOVE 4500 FEET...
    ...HIGH WIND WARNING FOR THE NORTHERN ROCKY MOUNTAIN FRONT
       AND THE CUT BANK AREA THIS AFTERNOON THROUGH LATE EVENING...

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREAT FALLS MT
600 AM MST THU JAN 22 2004

MTZ008>015-044>055-231210-
BEAVERHEAD-NORTHERN ROCKY MOUNTAIN FRONT-GLACIER-HILL-CASCADE-
CHOUTEAU-CENTRAL AND SOUTHERN LEWIS AND CLARK-MADISON-TOOLE-
LIBERTY-EASTERN PONDERA-BLAINE-SOUTHERN ROCKY MOUNTAIN FRONT-
EASTERN TETON-JUDITH BASIN-FERGUS-JEFFERSON-BROADWATER-MEAGHER-
GALLATIN-
600 AM MST THU JAN 22 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL AND SOUTHWEST
MONTANA

.DAY ONE...TODAY

HIGH WIND WARNING IN EFFECT FROM 12 PM THIS AFTERNOON TO 12 AM
FRIDAY FOR THE ROCKY MOUNTAIN FRONT AND THE CUT BANK AREA. PLEASE
REFER TO GTFNPWTFX FOR FURTHER DETAILS.

WINTER STORM WARNING IN EFFECT FROM 12 AM FRIDAY TO 5 AM SATURDAY
FOR THE ROCKY MOUNTAIN FRONT ABOVE 4500 FEET. PLEASE REFER TO
GTFWSWTFX FOR FURTHER DETAILS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

AN ARCTIC COLD FRONT WILL PUSH SOUTH INTO NORTH CENTRAL MONTANA ON
SATURDAY MORNING. THIS FRONT WILL MOVE SOUTH ACROSS NORTH CENTRAL
AND SOUTHWEST MONTANA DURING THE DAY ON SATURDAY. EXPECT
TEMPERATURES TO FALL QUICKLY BEHIND THE FRONT.
ADDITIONALLY...WIDESPREAD SNOW IS EXPECTED ACROSS THE REGION. THIS
IS BEING WATCHED CLOSELY...AS THE EXACT AMOUNTS ARE STILL A BIT
UNCERTAIN...BUT THE ENTIRE REGION MAY SEE A POSSIBLE WINTER WEATHER
ADVISORY OR WARNING SATURDAY AND SUNDAY.

EXPECT THE ARCTIC AIR TO CONTINUE AT LEAST INTO THE MIDDLE PART OF
NEXT WEEK.

.SPOTTER INFORMATION STATEMENT...

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