651 
FXUS65 KTFX 182151
AFDTFX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
251 PM MST FRI FEB 18 2011

.DISCUSSION...
TONIGHT THROUGH SUNDAY...THE UNSETTLED AND COLD WEATHER PATTERN
THAT HAS SET UP OVER THE REGION WILL CONTINUE THROUGH THE WEEKEND.
FOR TONIGHT...SCATTERED SNOW SHOWERS WEST OF THE DIVIDE WILL
CONTINUE TO MOVE NORTHEAST AND INTO CENTRAL MONTANA DURING THE
LATE AFTERNOON/EARLY EVENING HOURS. MOST AREAS WILL ONLY SEE A
DUSTING SNOW FROM THESE SNOW SHOWERS...BUT A FEW LOCATIONS COULD
SEE A QUICK INCH OF SNOWFALL FROM THE HEAVIER SNOW SHOWERS.
OVERNIGHT LOWS WILL BE ON THE COLD SIDE OVER NORTH CENTRAL
MONTANA...AND FOR NOW...NO WIND CHILL ADVISORY WILL BE ISSUED BUT
WE WILL CONTINUE TO MONITOR IT CLOSELY. FOR SATURDAY THROUGH
SUNDAY...THINGS BECOME A BIT MORE ACTIVE OVER SOUTHWEST MONTANA.
AN AREA OF LOW PRESSURE WILL MOVE ACROSS SOUTHERN IDAHO SATURDAY
AFTERNOON/NIGHT. THE TRACK OF THIS SURFACE LOW WILL ALLOW FOR SNOW
TO DEVELOP OVER SOUTHWEST MONTANA SATURDAY MORNING AND THEN
CONTINUE INTO SUNDAY AFTERNOON. THE HEAVIEST SNOW IS EXPECTED TO
FALL ON SATURDAY NIGHT. THERE IS THE POTENTIAL THAT A FEW MOUNTAIN
LOCATIONS COULD EXCEED A 12 OR 24 HOUR WARNING CRITERIA SNOW
AMOUNT...THUS A WINTER STORM WATCH HAS BEEN ISSUED FOR THE
MOUNTAINS IN MADISON AND GALLATIN COUNTIES. OVER NORTH CENTRAL
MONTANA...SNOW ACCUMULATIONS WILL GENERALLY BE LESS THAN AN INCH
OR SO FOR MOST AREAS...BUT COULD RANGE FROM 4 TO 7 INCHES IN THE
LITTLE BELT MOUNTAINS...THUS A WINTER WEATHER ADVISORY MIGHT BE
NEEDED FOR A PORTION OF CENTRAL MONTANA. OVERALL TEMPERATURES WILL
REMAIN COLD OVER THE NORTH...AND WIND CHILLS COULD ONCE AGAIN MEET
ADVISORY CRITERIA IN THE HAVRE AND CHINOOK AREAS ON SATURDAY
NIGHT. BRUSDA

SUNDAY NIGHT THROUGH FRIDAY...MODELS SHOW A LOW PRESSURE SYSTEM
MOVING OFF TO THE EAST TO BEGIN THE PERIOD. SOME LINGERING
MOISTURE OVER SOUTHWEST MONTANA MAY PROVIDE FOR A COUPLE SHOWERS
VERY EARLY MONDAY MORNING. A STRONG PACIFIC LOW LOOKS TO MOVE INTO
THE REGION LATER TUESDAY AND HEAD SOUTH OF MONTANA TOWARDS THE
GREAT BASIN. WITH PLENTY OF MOISTURE IN TOW...HAVE INCREASED POPS
OVER MUCH OF THE REGION FOR WEDNESDAY. WITH THE EXPECTED TRACK OF
THE LOW WELL SOUTH OF MONTANA...EXPECT NORTH-CENTRAL MONTANA TO
STAY SOMEWHAT DRIER. THIS LARGE LOW PRESSURE SYSTEM LOOKS TO
AFFECT THE REGION THROUGH FRIDAY KEEPING THE CHANCE OF
PRECIPITATION IN THE FORECAST. TEMPERATURES WILL BECOME MUCH
COLDER STARTING WEDNESDAY WITH HIGHS DROPPING INTO THE SINGLE
DIGITS AND LOWS BELOW ZERO IN MANY NORTH CENTRAL MONTANA
LOCATIONS.

&&

.AVIATION...
UPDATED 1745Z.
MOIST SOUTHWEST FLOW ALOFT CONTINUES TO OVERRIDE A COLD AIRMASS OVER 
CENTRAL MONTANA RESULTING IN AREAS OF LIGHT SNOW AND LOW CEILINGS. 
SNOW WILL GRADUALLY TAPER OFF AFTER 20Z THOUGH CEILINGS WILL 
CONTINUE TO BE LOW. VFR CONDITIONS PREVAIL FROM KDLN TO KBZN. 
MVFR/IFR CONDITIONS PREVAIL NORTH OF A KDLN TO KBZN LINE DUE TO LOW 
CEILINGS AND SNOW. MOUNTAINS WILL BE OBSCURED.

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF -12   6  -9  11 /  30  20  40  20 
CTB -19   4 -14   8 /  20  20  20  20 
HLN   4  18   1  20 /  30  30  40  30 
BZN   9  24   4  20 /  40  40  70  50 
WEY   6  27   2  21 /  30  60  80  80 
DLN  15  31  10  23 /  30  40  70  50 
HVR -17   1 -14   4 /  30  20  10  20 
LWT  -6   9  -8   9 /  30  30  40  30 

&&

.TFX WATCHES/WARNINGS/ADVISORIES...

...WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON 
FOR ELEVATIONS ABOVE 5000 FEET FOR GALLATIN AND MADISON
COUNTIES...

&&

$$

WEATHER.GOV/GREATFALLS