High Wind in Montana, March 18, 2004

SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MONTANA
930 AM MST THU MAR 18 2004

.SHORT TERM...ONLY MINOR CHANGES TO THE CURRENT FORECAST. HAVE
ADJUSTED SKY CONDITIONS FOR THE CENTRAL PORTION OF THE COUNTY
WARNING AREA AS CLOUDS HAVE THINNED CONSIDERABLY. HAVE ALSO ADJUSTED
POP AND WEATHER GRIDS...LEAVING SLIGHT POPS IN THE EAST FOR THE
MORNING HOURS. WEAK RIDGING OVER THE AREA TODAY WITH STRONG
DOWNSLOPE SURFACE GRADIENT. HIGH WIND WARNING WILL REMAIN IN PLACE
AS WIND SPEEDS PICK UP LATE THIS MORNING AND CONTINUE THROUGH
TONIGHT. EMANUEL

TONIGHT...THE LOW WILL DRAG A STRONG PACIFIC COLD FRONT THROUGH NORTH
CENTRAL MONTANA. MANY FACTORS ARE SIMILAR TO THE 8/16/02 EVENT WHICH
PRODUCED 60+ MPH GUSTS OVER MOST OF NORTH CENTRAL MONTANA. TEMPS WILL
NOT DROP MUCH FROM WARM AFTERNOON HIGHS BEFORE THE FRONT ARRIVES...
WHICH WONT BE UNTIL MIDNIGHT AT GREAT FALLS AND MAYBE 2-3 AM AT
HAVRE AND LEWISTOWN. WITH A POSSIBLE 20 DEGREE TEMPERATURE DROP
OCCURRING...ETA FORECASTING PRESSURE RISES OF 5-7 MB IN 3 HRS. SO
HAVE ELECTED TO HOIST A HIGH WIND WATCH FOR MOST OF NORTH CENTRAL
MONTANA FOR LATE TONIGHT/EARLY FRIDAY MORNING. THIS EVENT IS FIGHTING
CLIMATOLOGY IN THAT IT IS RARE FOR A COLD FRONT TO PRODUCE HIGH WINDS
DURING THE NIGHT.

FRIDAY AND FRIDAY NIGHT...WINDS WILL STILL BE GUSTY ACROSS THE
CWA FRIDAY WITH STEEP LAPSE RATES PRESENT. SOME ISOLATED MOUNTAIN
SHOWERS ARE POSSIBLE...MAINLY IN THE SOUTHERN ZONES WHERE THE FRONT
STALLS OUT. ITS LIKELY ANOTHER HIGH WIND WATCH OR WARNING WILL BE
NEEDED FOR THE ROCKY MOUNTAIN FRONT FRIDAY AFTERNOON...BUT FOR NOW
WILL TAKE THINGS ONE EVENT AT A TIME. POMEROY

SATURDAY THROUGH MONDAY NIGHT...ECMWF/UKMET/GFS HAVE BEEN IN A
GROOVE OF BEING IN GOOD AGREEMENT WITH GENERAL TRENDS AND ALSO HAVE
BEEN RELATIVELY CONSISTENT RUN-TO-RUN. UPPER RIDGE TO BUILD OVER THE
PACIFIC NORTHWEST ON SATURDAY THEN MOVE GRADUALLY EAST INTO EARLY
NEXT WEEK AND ALSO WEAKEN. UPPER RIDGE THEN SHOULD MOVE OVER THE
FORECAST AREA ON MON. AT THE SURFACE UPSLOPE FLOW SHOULD RULE FROM
SATURDAY INTO SUNDAY NIGHT BUT THEN COULD SEE SOME WEAK DOWNSLOPE
WINDS OVER THE PLAINS BY MONDAY OR MONDAY NIGHT. UPPER RIDGE SHOULD
BE WEAK ENOUGH BY MONDAY TO ALLOW A THREAT OF PRECIPITATION FOR THE
WESTERN MOUNTAINS. GFS HAS SOME QPF FOR THE EAST SLOPES SATURDAY
NIGHT INTO SUNDAY MORNING. QPF APPEARS DUE TO LOW LEVEL UPSLOPE
FLOW. ALTHOUGH IT IS NOT UNREASONABLE THAT THERE COULD BE SOME LIGHT
PRECIPITATION FROM THE UPSLOPE FLOW...ETA/ETA12 ARE DRY FOR THIS
PERIOD/AREA. WILL HOLD OFF MENTIONING PRECIPITATION UNTIL FURTHER
RUNS OF THE GFS SHOW QPF AS WELL AS THE ETA/ETA12. LOWERED SOME
TEMPERATURES FOR SAT INTO SUN OVER THE PLAINS TO BE MORE IN LINE
WITH GFS TEMPERATURE FORECASTS. WITH GOOD EASTERLY FLOW HAVRE SHOULD
BE AFFECTED BY SNOW FIELDS TO THE EAST WHICH WILL HELP KEEP
TEMPERATURES ON THE COOL SIDE. BLANK

TUESDAY THROUGH THURSDAY...EXPECT AREAS OF MOISTURE IN A FAIRLY
STRONG WESTERLY FLOW ALOFT DURING PERIOD WITH GFS AND ECMWF SIMILAR.
WILL MAKE LITTLE CHANGE AS TIMING OF FAST MOVING WAVES DIFFICULT AND
UNCERTAIN THIS FAR OUT. PATTERN DOES LOOK DRY FOR THE PLAINS WITH
SOME LIGHT SHOWERS OVER WESTERN AND SOUTHWESTERN MOUNTAINS. GFS
BRINGS IN COLD...CANADIAN AIR AT END OF PERIOD. BELIEVE IT MIGHT BE A
LITTLE FAST AND BACKED OFF ON EFFECTS A LITTLE. KURDY

&&

.CCF NUMBERS
GTF EN 060/029 046/022 050 19120
    BBBBB 025/052 027/055 029/053 028/048 030 00000000000
CTB NN 057/028 043/020 046 19120
    BBBBB 022/048 025/047 029/050 028/044 024 00000000000
HLN EE 062/032 052/028 056 1902-
    BBEEE 030/056 030/061 031/055 030/054 030 00000------
BZN EB 060/033 055/026 054 19020
    BBBBB 025/055 027/059 028/056 027/052 029 00000000000
WEY EB 050/030 046/014 047 19020
    BBBBB 016/050 016/052 023/048 022/034 022 00000222222
DLN EB 062/037 058/026 056 190-0
    BBEEE 032/056 033/062 030/056 027/052 026 000-0222222
HVR EN 056/028 051/022 041 19220
    BBBBB 019/038 019/052 027/052 026/045 023 00000000000
LWT EN 060/032 051/025 046 19220
    BBBBB 024/042 024/056 029/052 028/049 027 00000000000

&&

.TFX...HIGH WIND WARNING FOR THE ROCKY MOUNTAIN FRONT AND ADJACENT
       PLAINS THURSDAY THROUGH THURSDAY EVENING.
       HIGH WIND WATCH FOR THE REST OF NORTH CENTRAL MONTANA LATE
       THURSDAY NIGHT THROUGH FRIDAY MORNING.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREAT FALLS MT
352 AM MST THU MAR 18 2004

MTZ009>013-044>051-191210-
BLAINE-CASCADE-CHOUTEAU-EASTERN GLACIER-EASTERN PONDERA-
EASTERN TETON-FERGUS-HILL-JUDITH BASIN-LIBERTY-
NORTHERN ROCKY MOUNTAIN FRONT-SOUTHERN ROCKY MOUNTAIN FRONT-TOOLE-
352 AM MST THU MAR 18 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR A PORTION OF NORTH CENTRAL
MONTANA

.DAY ONE...TODAY

A HIGH WIND WARNING HAS BEEN ISSUED FOR THE ROCKY MOUNTAIN FRONT AND
NEARBY PLAINS FOR LATE THIS MORNING THROUGH TONIGHT. REFER TO
GTFNPWTFX FOR DETAILS.

A HIGH WIND WATCH HAS BEEN ISSUED FOR PORTIONS OF NORTH CENTRAL
MONTANA FOR LATE TONIGHT THROUGH FRIDAY MORNING. REFER TO GTFNPWTFX
FOR DETAILS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

A HIGH WIND WATCH HAS BEEN ISSUED FOR PORTIONS OF NORTH CENTRAL
MONTANA FOR LATE TONIGHT THROUGH FRIDAY MORNING. REFER TO GTFNPWTFX
FOR DETAILS.

.SPOTTER INFORMATION STATEMENT...

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

MTZ008-014-015-052>055-191210-
BEAVERHEAD-BROADWATER-CENTRAL AND SOUTHERN LEWIS AND CLARK-GALLATIN-
JEFFERSON-MADISON-MEAGHER-
352 AM MST THU MAR 18 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHWEST AND A PORTION OF
NORTH CENTRAL MONTANA

.DAY ONE...TODAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.