Area Forecast Discussion
Issued by NWS Great Falls, MT

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS65 KTFX 282026
AFDTFX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
226 PM MDT THU APR 28 2016

...DRYING AND WARMING CONDITIONS THROUGH NEXT WEEK...

.DISCUSSION...

TONIGHT THROUGH SATURDAY...THE WIDESPREAD PRECIPITATION WILL
GRADUALLY TRANSITION TO A MORE SHOWERY WEATHER PATTERN INTO THIS
WEEKEND. A WEAK LOW PRESSURE AREA WITHIN THE MAIN TROUGH OVER THE
AREA WILL MOVE NORTH ACROSS WESTERN MONTANA OVERNIGHT,
ESSENTIALLY CUTTING OFF THE MOISTURE FEED FROM THE EAST. AS A
RESULT, THE RAIN AND MOUNTAIN SNOW OVER THE FORECAST AREA WILL
BECOME MORE SHOWERY AND DIMINISH OVERNIGHT. HOWEVER, BREAKS IN THE
CLOUDS WITH LIGHTER WINDS WILL COMBINE WITH THE LOW LEVEL
MOISTURE TO POSSIBLY CAUSE PATCHY FOG TO DEVELOP IN SOME AREAS,
MOSTLY AFTER MIDNIGHT AND INTO FRIDAY MORNING. AN UPPER LEVEL LOW
PRESSURE TROUGH WILL THEN DEEPEN ALONG THE PACIFIC NORTHWEST COAST
ON FRIDAY AND MOVE INTO WESTERN MONTANA ON SATURDAY. THIS WILL
PLACE A WARMER AND MORE UNSTABLE SOUTHERLY FLOW ALOFT OVER THE
AREA. THIS WILL RESULT IN MAINLY AFTERNOON AND EVENING SCATTERED
SHOWERS, WITH POSSIBLY A FEW WEAK THUNDERSTORMS, THAT WILL SPREAD
WEST TO EAST ACROSS THE FORECAST AREA FRIDAY INTO SATURDAY. ALSO,
TEMPERATURES WILL WARM THROUGH THIS PERIOD FROM SLIGHTLY BELOW
NORMAL TODAY TO SLIGHTLY ABOVE NORMAL BY SATURDAY.  COULSTON

SATURDAY NIGHT THROUGH THURSDAY...MEDIUM RANGE MODELS COMING INTO
BETTER AGREEMENT WITH BRINGING AN END TO THE COOL UNSETTLED
PATTERN OF THE PAST WEEK. THE ELONGATED UPPER TROF WEAKENS TO
START THE PERIOD AS THE ASSOCIATED DEFORMATION ZONE DRIFTS
FURTHER SOUTH IN RESPONSE TO HIGH PRESSURE THAT BEGINS BUILDING
ACROSS THE NORTH. ISOLATED SHOWERS SATURDAY NIGHT WILL BE
CONFINED TO PORTIONS OF SOUTHWEST MONTANA AND TO THE WESTERN
MOUNTAINS. THE UPPER TROF SPLITS ON SUNDAY WITH THE WESTERN
PORTION RESIDING OVER NEVADA/UTAH AND THE EASTERN PORTION FILLING
AS IT PUSHES INTO THE UPPER MIDWEST. CIRCULATION AROUND THE
WESTERN LOBE WILL CONTINUE TO BRING SOME SHOWERS TO THE WESTERN
AND SOUTHWEST MOUNTAINS. HIGH PRESSURE WILL THEN BUILD OVER THE
AREA MONDAY USHERING IN WARMER AND DRY CONDITIONS THAT WILL
CONTINUE THROUGH THE REMAINDER OF THE PERIOD. TEMPERATURES WILL
BE NEAR SEASONAL AVERAGES SUNDAY BUT WILL CONTINUE TO SLOWLY WARM
EACH DAY THROUGH THURSDAY.

&&

.AVIATION...
UPDATED 1810Z.

A WEAK LOW PRESSURE CENTER OVER SOUTHWEST MONTANA WILL GRADUALLY
DRIFT INTO NORTHWEST MONTANA DURING THE PERIOD. AS A RESULT, THE
MOIST EASTERLY FLOW WILL CUT OFF FROM THE MAIN FEED OF MOISTURE AS
IT SHIFTS MORE SOUTHERLY. LIGHT PRECIPITATION WITH MOUNTAIN
OBSCURATION WILL GRADUALLY DECREASE AND BECOME MORE SHOWERY THROUGH
01Z, ALLOWING MVFR/IFR CONDITIONS TO IMPROVE TO LOW VFR/HIGH MVFR
WITH ONLY PARTIAL MOUNTAIN OBSCURATION. HOWEVER, LOW LEVEL MOISTURE
WILL LINGER OVER THE AREA OVERNIGHT INTO FRIDAY MORNING, ALLOWING
PATCHY FOG AND LOW CLOUDS TO BRING OCCASIONAL MVFR/IFR CONDITIONS
BACK TO THE AREA AFTER 04Z, CAUSING MORE WIDESPREAD MOUNTAIN
OBSCURATION.  COULSTON

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  30  53  34  57 /  30  20  20  20
CTB  30  52  33  57 /  20  20  20  30
HLN  32  57  36  59 /  20  30  30  30
BZN  31  55  34  56 /  20  20  20  30
WEY  27  48  29  49 /  20  40  40  30
DLN  29  54  34  55 /  20  40  30  30
HVR  33  56  36  60 /  10  10  10  20
LWT  31  50  34  54 /  30  10  20  20

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

WEATHER.GOV/GREATFALLS


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.