High Wind in Montana, June 27, 2002

SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
900 PM MDT WED JUN 26 2002

UPDATES PLANNED FOR ZONES AND STATE

.SHORT TERM...LOTS OF CONVECTIVE DEBRIS CLOUDS CONTINUE TO SPREAD N
OVER THE FORECAST AREA. LEADING EDGE WAS NEAR A CTB/GTF/BIL LINE AT
0230Z. WITH SE FLOW ALOFT FORECAST TO VEER TO A MORE SLY DIRECTION
EXPECT DEBRIS CLOUDS TO SPREAD OVER THE ENTIRE AREA BY MORNING.
CLOUDS MAY DISSIPATE SOME LATER ON BUT WILL GO MOSTLY CLOUDY.
WILL ALSO BOOST LOWS TONIGHT FOR MOST AREAS. STILL SOME
CONVECTION OCCURRING OVER BEAVERHEAD COUNTY AHEAD OF A VORTICITY
CENTER OVER SRN ID. MESOETA AND RUC APPEAR TO BE THE ONLY MODELS
PICKING UP ON THIS FEATURE. STILL EXPECT CONVECTION TO DIMINISH AFTER
DARK OVER THAT AREA. WILL DROP MENTION OF SHOWERS/THUNDERSTORMS
ELSEWHERE OVER THE AREA FOR TONIGHT. QUICK CHECK OF 00Z MESOETA
FORECAST CONVECTION PARAMETERS FOR THU AFTERNOON STILL INDICATES THE
POSSIBILITY OF STRONG THUNDERSTORMS OVER THE NRN E SLOPES. BLANK

.EXTENDED...MODELS IN GOOD AGREEMENT WITH INCREASED SW FLOW ALOFT
OVER THE AREA SAT NIGHT INTO SUN NIGHT. ECMWF IS STRONGER THAN THE
LATEST AVN WITH A SHORTWAVE MOVING THROUGH THE AREA SAT NIGHT. WILL
CONTINUE WITH SLIGHT CHANCE POPS FOR SAT NIGHT. ON SUN LATEST AVN
HAS SOME LIFT OVER SW PROBABLY ASSOCIATED WITH A LINGERING FRONT NEAR
SW MT. MODEL DOES NOT HAVE MUCH RH BUT WILL GO WITH SLIGHT CHANCE
POPS FOR SW MT. FARTHER N EXPECT DOWNSLOPE EFFECTS TO INHIBIT
PRECIPITATION EXCEPT POSSIBLY OVER THE MOUNTAINS. ON TUE ECMWF AND
AVN HAVE A FAIRLY STRONG WLY FLOW ALOFT OVER THE AREA WHILE LATEST
UKMET HAS MORE OF A SW FLOW. WILL GO WITH THE ECMWF/AVN SOLUTION AND
GO WITH A DRY FORECAST BASED ON 00Z AVN RH/QPF PROGS. FOR TUE AND
WED WILL HAVE TO DEAL WITH THE NEXT PAC UPPER TROUGH. UKMET AND
AVN ARE STRONGER WITH THE TROUGH WITH THE UKMET ALSO BEING
FASTER THAN THE AVN. ECMWF ON THE OTHER HAND IS WEAKER WITH THE
UPPER TROUGH. WILL LEAN TOWARDS THE AVN SOLUTION BUT AT THIS POINT
WILL NOT GO WITH AS MUCH COOLING OR WIND AS IMPLIED BY THE AVN.
WILL GO WITH SLIGHT CHANCE POPS BOTH DAYS. BLANK

.CCF NUMBERS
GTF BB 060/094 058/090 057 03124
    BBNBB 088/056 080/052 075/045 080/050 075 22122112222
CTB BB 058/090 054/086 055 03124
    BNNBB 084/052 075/050 071/042 076/048 072 22121111222
HLN BB 060/096 059/092 057 03124
    BBBBB 089/056 085/052 077/050 082/054 075 22122111222
BZN BB 054/091 053/087 053 03123
    BBBBB 087/052 086/050 080/045 082/049 079 22122111222
WEY BB 050/088 048/083 048 03223
    BBBBB 083/042 082/042 076/041 076/041 074 22122111222
DLN BB 054/091 055/089 054 03124
    BBBBB 088/052 085/050 079/044 081/050 076 22122111222
HVR BB 058/096 061/094 059 03013
    BBNBB 092/057 084/052 078/048 082/053 079 22122111122
LWT BB 058/091 055/086 054 03013
    BBNBB 085/054 083/051 075/044 079/050 078 22122111222=

.TFX...FLOOD WARNING FOR GLACIER COUNTY (ZONES 9 AND 10).