AREA FORECAST DISCUSSION

 
 FXUS65 KGGW 101103
 AFDGGW
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE GLASGOW MT
 403 AM MST WED FEB 10 2010
 
 .SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH FRIDAY...
 WINDS HAVE DIMINISHED THE LAST FEW HOURS OVER NORTHEAST MONTANA.
 WILL BE ABLE TO LET WIND CHILL ADVISORY EXPIRE. 
 
 SHORTWAVE TROUGHS WILL MOVE THROUGH NORTHEAST MONTANA ON NORTHWEST
 FLOW ALOFT THE NEXT FEW DAYS. THE SHORTWAVES THIS MORNING AND THIS
 EVENING WILL BRING SOME CLOUDS TO THE AREA WITH SOME CLEAR
 PERIODS. TEMPERATURES WILL BE WARMER TODAY AS THE COLDEST AIR HAS
 RECEDED FROM NORTHEAST MONTANA AND TEMPERATURES IN MANY AREAS ARE
 STARTING OUT 5 TO 10 DEGREES HIGHER THAN YESTERDAY.
 
 THE SHORTWAVES MOVING THROUGH THURSDAY WILL BE SOMEWHAT STRONGER
 WITH MORE MOISTURE. WILL MENTION A SLIGHT CHANCE OF SNOW THURSDAY
 AND THURSDAY NIGHT. 
 
 ON FRIDAY...MID AND UPPER LEVEL MOISTURE MOVING IN FROM THE WEST
 WILL START TO OVERRUN A STATIONARY FRONT OVER CENTRAL MONTANA. A
 STRONG SHORTWAVE WILL DROP SOUTH THROUGH MANITOBA BRINGING A COLD
 FRONT TOWARDS EASTERN MONTANA. THE MODELS HAVE A BAND OF SNOW
 DEVELOPING EITHER DURING THE DAY FRIDAY (GFS) OR FRIDAY NIGHT
 (ECMWF AND NAM). WILL MENTION A CHANCE OF SNOW ON FRIDAY IN THE
 SOUTHWEST HALF OF THE FORECAST AREA FOR NOW UNTIL THE MODELS CAN
 RESOLVE THEIR TIMING DIFFERENCES. FORRESTER
 
 
 .LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...
 A LITTLE MORE ACTIVE PATTERN IN THE OFFING...AND NOT QUITE SO
 COLD.
 
 BACKDOORING ARCTIC FRONT FROM THE NE FRI NIGHT ENDS UP STALLING
 JUST TO OUR W-SW. WITH PLENTIFUL MOISTURE OVER OUR W...THIS SETS
 UP A GOOD OVERRUNNING SNOW PATTERN FOR PETROLEUM COUNTY...AIDED BY UPSLOPE.
 MODELS ALL SHOW THIS TO PRODUCE SIGNIFICANT SNOWFALL WITH QPF UP
 TO .25. HAVE RAISED POPS FOR FRI NIGHT/SAT...ELSEWHERE A CHANCE OF
 SNOW TOO...BUT SHORT-LIVED JUST BEHIND THE FRONT. SMALL CLOSED
 UPPER LOWS MOVES S INTO ND AGAIN...WITH AN ARCTIC HIGH FROM THE N
 CLEARING OUT NE MT BY SAT NIGHT/SUN. THIS SIMILAR TO THIS PAST
 SUNDAY...BUT NOT AS COLD.
 
 UPPER RIDGE REMAINS JUST TO OUR W...NOT A GOOD POSITION FOR A LOT
 OF WARMING...BUT A LITTLE MORE ACTIVE PATTERN ALSO...WHICH CAN
 PROVIDE SOME WARMING WITH INCREASED MIXING. MODEL CONSENSUS HAS A
 SHORTWAVE FROM THE WNW MOVING ACROSS OUR AREA MONDAY AND ANOTHER
 WEDNESDAY. THERE IS QUITE A BIT OF VARIATION ON DETAILS OF
 STRENGTH AND LOCATION WITH THESE...BUT ENOUGH OF A THREAT TO
 RAISE POPS FOR ONE PERIOD WITH EACH OF THESE...THAT IS MONDAY AND
 WEDNESDAY.
 
 THE MONDAY SYSTEM  MAY BRING A LITTLE MIXING IN THE FORM OF W-NW
 WIND TO TO WARM THINGS UP A BIT...NOT QUITE TO FREEZING MOST
 AREAS THOUGH. THE WEDNESDAY SYSTEM ALSO SHOWS THIS LIMITED MIXING
 POTENTIAL TOO. MODEL GUIDANCE IS SHOWING A WIDE VARIATION WITH
 TEMPERATURES DURING THIS TIME THOUGH...INDICATING THE DIFFICULTY
 OF MIXING AND SNOW OVER...AND WILL PREFER TO STAY ON THE COLD
 SIDE. SIMONSEN
 
 &&
 
 .AVIATION...
 GENERALLY VFR WITH SCATTERED BROKEN CLOUD LAYERS AT 8K FT AGL AND
 ABOVE. A FEW PATCHES OF VALLEY FOG REDUCING VISIBILITY BRIEFLY TO
 3-5 MILES ARE POSSIBLE IN THE MILK AND LOWER MISSOURI RIVER
 VALLEYS AROUND SUNRISE THIS MORN. THESE FOG PATCHES WILL BE
 SHORTLIVED. SIMONSEN
 
 &&
 
 .CLIMATE...
 GLASGOW HAS HAD 24 CONSECUTIVE DAYS BELOW FREEZING. EARLIER THIS
 WINTER...THERE WAS 23 DAYS IN A ROW BELOW FREEZING...FROM DEC
 18TH THRU JAN 9TH. THE 24 DAYS IN A ROW IS THE LONGEST SUCH
 STRETCH OF BELOW FREEZING HIGHS SINCE 24 DAYS IN A ROW IN FEB
 2001. WE HAVE A GOOD CHANCE OF REACHING 30 DAYS IN A ROW...WHICH
 WOULD BE THE LONGEST SUCH STRETCH SINCE THE WINTER OF 1996-97.
 THE RECORD FOR GLASGOW IS 66 DAYS IN A ROW BELOW FREEZING IN THE
 WINTER OF 1978-79. SIMONSEN
 
 &&
 
 .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
 
 &&
 
 

 
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