FXUS65 KTFX 150255
AFDTFX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
855 PM MDT SUN MAR 14 2010
.UPDATE...
STRONG UPPER RIDGE OVER THE PACIFIC NORTHWEST WILL MOVE OVER THE
FORECAST AREA LATER TONIGHT. ALTHOUGH THE UPPER RIDGE WILL BE
STRONG DO EXPECT SOME HIGH CLOUDS TO AFFECT THE AREA AND HAVE LEFT
THE SKY FORECAST FOR THE AFTER MIDNIGHT PORTION OF TONIGHT ALONE.
SATELLITE IMAGERY AND OBSERVATIONS SHOWED CLEAR SKIES EXCEPT FOR
A FEW WISPY HIGH CLOUDS OVER NORTH CENTRAL MONTANA AS OF MID-
EVENING SO WILL LOWER SKY COVER TO CLEAR OVER THE SOUTHERN ZONES
FOR THE REST OF THIS EVENING. BASED ON EXPECTED EASTERLY WINDS
RESTRICTED THE FOG FOR LATER TONIGHT TO JUST THE NORTHEAST QUARTER
OF BLAINE COUNTY. LOWERED LOWS FOR TONIGHT FOR BELGRADE AND WEST
YELLOWSTONE AS THEY SHOULD SEE GOOD RADIATIONAL COOLING
CONDITIONS. WITH THE EXPECTED GOOD RADIATIONAL COOLING CONDITIONS
AT BELGRADE ADDED SOME PATCHY FREEZING FOG FOR THE ASSOCIATED
VALLEY. BLANK
&&
.AVIATION...
UPDATED 0000Z.
VFR CONDITIONS WILL CONTINUE FOR THE NEXT 24 HOURS WITH MOSTLY CLEAR
SKIES AND GENERALLY LIGHT WINDS. HIGH PRESSURE WILL CONTINUE TO
BUILD INTO THE AREA FROM THE WEST THROUGH MONDAY. ANY CUMULUS CLOUDS
OVER THE MOUNTAINS THIS AFTERNOON WILL DISSIPATE THIS EVENING.
ISOLATED PATCHY FOG AND LOW CLOUDS MAY FORM IN SOUTHWEST VALLEYS
OVERNIGHT BUT IMPACTS SHOULD BE MINIMAL. SCATTERED HIGH CLOUDS WILL
SPREAD INTO THE AREA FROM THE WEST TOMORROW.
&&
.PREV DISCUSSION...
/ISSUED 600 PM MDT SUN MAR 14 2010/
TONIGHT...A HIGH PRESSURE RIDGE WILL BUILD OVER THE ZONES
TONIGHT THROUGH MONDAY. UNDERNEATH THE RIDGE...THE AIRMASS WILL
WARM AND CONTINUE TO DRY. MAIN PROBLEM WILL BE TEMPS. SNOW IS
STILL ON THE GROUND IN NORTHEAST MONTANA AND KEEPING TEMPS BELOW
NORMALS. ELSEWHERE...WITH LIGHT WINDS AND CLEAR SKIES...WILL HAVE
SOME BIG SWINGS BETWEEN HIGH AND LOW TEMPS. BY TUESDAY...THE RIDGE
WILL HAVE MOVED OVER EASTERN MONTANA. FLOW ALOFT WILL SWITCH TO
THE SOUTHWEST AND ALLOW MOISTURE TO ADVECT INTO THE CWA. A LOW
PRESSURE TROF WILL BE OVER THE EASTERN PACIFIC AND A WEAK
SHORTWAVE AHEAD OF THIS SYSTEM WILL MOVE THROUGH THE FLOW ALOFT.
THIS MAY BRING ISOLATED SHOWERS OVER THE ROCKIES BUT IT WILL BE
MOVING INTO A STRONG RIDGE AND SHOULD HAVE LITTLE IMPACT. TEMPS
WILL CONTINUE TO TREND UPWARDS AND BE WELL ABOVE NORMALS BY
TUESDAY. ZELZER
TUESDAY NIGHT THROUGH SUNDAY...THE PERIOD BEGINS
WITH A WEAK UPPER TROF MOVING ALONG THE INTERNATIONAL BORDER. WITH
THE FLOW ALOFT REMAINING PREDOMINATELY WESTERLY AND DOWNSLOPE FOR
THE PLAINS...EXPECT ANY PRECIPITATION TO BE CONFINED TO HIGHER
TERRAIN. THE MODELS ARE IN GENERAL AGREEMENT THURSDAY AS AN UPPER
RIDGE AMPLIFIES OVER THE WEST COAST AND AN UPPER TROF DIGS OVER
THE COUNTY WARNING AREA. THIS HERALDS A CHANGE IN THE OVERALL
PATTERN FROM DRY AND MILD TO MOIST AND SOMEWHAT UNSTABLE.
NORTHWEST FLOW ALOFT WILL PERSIST OVER THE AREA THURSDAY THROUGH
SATURDAY. AS POCKETS OF ENERGY MOVE THROUGH THIS FLOW
REGIME...SCATTERED MOUNTAIN SNOW WILL DEVELOP ALONG WITH ISOLATED
RAIN AND/OR SNOW SHOWERS OVER THE PLAINS. THE MODELS DIVERGE ON
SUNDAY WITH THE EUROPEAN BRINGING A WEAK UPPER RIDGE TO THE AREA
WHILE THE GFS CONTINUES WITH UNSTABLE NORTHWEST FLOW ALOFT.
TEMPERATURES WILL START OUT VERY WARM...CLOSE TO 15 DEGREES ABOVE
SEASONAL AVERAGES WEDNESDAY. WITH THE PASSAGE OF A SURFACE COLD
FRONT LATE WEDNESDAY...AFTERNOON TEMPERATURES WILL BEGIN A GRADUAL
COOLING TREND WITH READINGS AT OR SLIGHTLY BELOW SEASONAL AVERAGES
BY THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 29 60 35 65 / 0 0 0 0
CTB 25 58 29 62 / 0 0 0 0
HLN 27 60 31 61 / 0 0 0 0
BZN 18 56 26 56 / 0 0 0 0
WEY 12 45 17 47 / 0 0 0 0
DLN 25 54 28 56 / 0 0 0 0
HVR 12 45 17 45 / 0 0 0 0
LWT 26 56 29 61 / 0 0 0 0
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BLANK
LONG TERM...GUSTAFSON
AVIATION...GUSTAFSON
WEATHER.GOV/GREATFALLS
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