000
FXUS65 KGGW 030231
AFDGGW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GLASGOW MT
831 PM MDT THU SEP 2 2010

.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH SATURDAY...

A LIGHT NORTHWEST FLOW PATTERN IS EXPECTED THIS EVENING WITH WINDS
CALMING TO 10 KTS OR LESS ACROSS THE CWA. SURFACE HIGH PRESSURE AND
AND UPPER LEVEL RIDGE WILL CONTINUE TO FILTER INTO THE REGION
OVERNIGHT AND ALLOW SURFACE TEMPERATURES TO LOWER INTO THE MID AND
LOWER 40S WITH CLEAR SKIES OVER HEAD. GAH

PREVIOUS SHORT TERM DISCUSSION...
SURFACE HIGH PRESSURE MOVING IN FROM THE WEST WILL BEGIN TO EASE
WINDS ACROSS THE CWA THIS EVENING. A LAKE WIND ADVISORY WILL
EXPIRE AT 7 PM TONIGHT AS THE PRESSURE GRADIENT RELAXES.

TONIGHT THROUGH SATURDAY... A HIGH PRESSURE RIDGE MOVES INTO THE
REGION AND PRODUCES MOSTLY CLEAR SKIES AND DRY CONDITIONS.
TEMPERATURES ARE EXPECTED TO RISE TO NEAR NORMAL RANGE IN THE MID 70S
FRIDAY TO ABOVE NORMAL IN THE LOWER 80S SATURDAY. WINDS SHOULD
ALSO BE NICE AND LIGHT FROM THE SOUTH INTO THE EARLY WEEKEND. A
STRONG UPPER TROF WILL DEVELOP OVER THE COAST OF BRITISH COLUMBIA.
THIS WILL SHIFT THE UPPER LEVEL WIND PATTERN OVER CENTRAL AND
EASTERN MONTANA FROM THE WEST TO THE SOUTHWEST. THIS WILL INCREASE
THE INSTABILITY AND LEAD TO POSSIBLE THUNDERSTORM DEVELOPMENT IN
THE AFTERNOON AND EVENING. GAH/RSMITH


.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...
MODELS ARE COMING INTO AGREEMENT WITH SYSTEM TO AFFECT THE AREA
ABOUT LABOR DAY. BANDED PRECIP LOOKS TO MOVE INTO THE SUNDAY NIGHT
WITH MORE WIDESPREAD SHOWERS TO AFFECT THE AREA MONDAY...MOVING
OUT MONDAY NIGHT. ALSO LOWERED MAX TEMP FOR MONDAY. REST OF
FORECAST LOOKED GOOD. JAMBA

PREVIOUS DISCUSSION...
UPPER TROF ROTATING INTO MONTANA EARLY IN THE EXTENDED
PERIOD...PUSHING COLD FRONT THROUGH EASTERN MONTANA BY SUNDAY
EVENING. SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED TO DEVELOP
ALONG AND AHEAD OF THE COLD FRONT...SPREADING EAST ON SUNDAY.
UPPER TROF MOVES OVER MONTANA SUNDAY NIGHT AND MONDAY...WITH MORE
WIDESPREAD RAIN EXPECTED. MODELS IN PRETTY GOOD AGREEMENT WITH
THIS SYSTEM ALTHOUGH THE GFS CLOSES OFF THE UPPER SYSTEM MORE THAN
THE ECMWF/GEM.

SLIGHT RIDGE DEVELOPS ON TUESDAY AS NEXT SHORTWAVE DROPS INTO THE
PACIFIC NORTHWEST. SOME MODEL DIFFERENCES WITH ECMWF STRONGER WITH
THE NORTHERN PORTION OF THE TROF...AND THUS NOT PULLING AS MUCH
WARM DRY AIR NORTH INTO MONTANA AS THE GFS DOES. WITH HIGH
PRESSURE OVER THE NORTHERN PLAINS...AND SOUTHWEST FLOW ALOFT OUT
OF THE GREAT BASIN WILL KEEP POPS SLIGHTLY ABOVE CLIMO THROUGH THE
END OF THE WEEK...WITH TEMPERATURES WARMING SLOWLY. EBERT


&&

.AVIATION...
VFR. MAINLY CLEAR SKIES AND LIGHT SOUTH WINDS CAN BE EXPECTED
OVERNIGHT TONIGHT. CLEAR SKIES WILL EXTEND INTO FRIDAY WITH SOUTH
WINDS PICKING UP AT 8-12 KTS BY LATE MORNING. GILCHRIST


&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.


&&

$$

WEATHER.GOV/GLASGOW

NWS GGW Office Area Forecast Discussion