716
FXUS65 KTFX 110928
AFDTFX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
328 AM MDT TUE MAR 11 2025
KEY MESSAGES
- TEMPERATURES MODERATE BACK TO ABOVE SEASONAL AVERAGES THROUGH
THURSDAY WITH BREEZY TO WINDY CONDITIONS AT TIMES AND LOCALLY
STRONGER WINDS POSSIBLE ACROSS PARTS OF SOUTHWEST MONTANA.
- A PACIFIC STORM SYSTEM MOVING ACROSS THE INTERIOR WESTERN US LATE
THIS WEEK WILL BRING COOLER TEMPERATURES FRIDAY AND SATURDAY ALONG
WITH AREAS OF PRECIPITATION AND POTENTIALLY IMPACTFUL SNOWFALL TO
SOME SOUTHWEST MONTANA MOUNTAIN RANGES.
DISCUSSION
- METEOROLOGICAL OVERVIEW:
A ZONAL/WESTERLY FLOW REMAINS IN PLACE ACROSS THE NORTHERN
ROCKIES AND MT TODAY WITH AN EMBEDDED PLUME PACIFIC MOISTURE
CONTRIBUTING TO CONSIDERABLE MID-HIGH LEVEL CLOUD-COVER. AN SUBTLE
SHORTWAVE DISTURBANCE MOVING EAST ALONG THE US/CANADIAN BORDER
AND WEAK LIFT NEAR THE REAR ENTRANCE OF AN UPPER LEVEL JET MAX
MOVING ACROSS THE CANADIAN PRAIRIES WILL HELP PRODUCE SOME LIGHT
SNOW SHOWERS ALONG PORTIONS OF NORTH-CENTRAL MT NEAR THE DIVIDE
WITH A FEW FLURRIES/SPRINKLES OR LIGHT SHOWERS POTENTIALLY
TRACKING FURTHER EAST ACROSS NORTH-CENTRAL MT. OTHERWISE, DRY
CONDITIONS PREVAIL WITH TEMPERATURES SEVERAL DEGREES WARMER THAN
YESTERDAY.
WEAK UPPER RIDGING SHIFTS ACROSS THE AREA TONIGHT THROUGH WEDNESDAY
NIGHT WITH FLOW ALOFT BACKING TO SOUTHWESTERLY FOR MAINLY DRY
CONDITIONS WITH TEMPERATURES WARMING A BIT MORE ABOVE AVERAGE.
AFTERNOON MIXING WILL SUPPORT BREEZY WINDS TODAY AND AGAIN WEDNESDAY
FOR MOST AREAS WITH DEVELOPING SURFACE LOW PRESSURE AND INCREASED
SOUTHWEST MID-LEVEL FLOW SUPPORTING WINDIER CONDITIONS ACROSS
SOUTHWEST MT WEDNESDAY AFTERNOON. THERE IS STILL POTENTIAL FOR A
PERIOD OF STRONGER WINDS IN/NEAR THE MADISON RIVER VALLEY AND
SOUTHWEST MT MOUNTAINS LATE WEDNESDAY AFTERNOON/OVERNIGHT AS 700MB
FLOW INCREASES TO 40-50KTS AND BECOMES MORE ALIGNED WITH THE TERRAIN
PACIFIC UPPER LEVEL TROUGH SHIFTS INLAND THURSDAY AND SPLITS WITH
THE STRONGER SOUTHERN PORTION TRACKING ACROSS THE SW US AND EMERGING
IN THE SOUTHERN US PLAINS FRIDAY WITH THE WEAKER NORTHERN PORTION
SHIFTING EAST ACROSS THE NORTHERN ROCKIES AND MT THURSDAY NIGHT INTO
FRIDAY. WHILE THE MORE IMPACTFUL PRECIPITATION/SNOW WITH THIS SYSTEM
LOOKS TO BE SOUTHEAST OF THE AREA, THERE IS PERIOD OF LARGER SCALE
ASCENT WITH THE TROUGH PASSAGE AND SOMEWHAT ANOMALOUS MOISTURE (PWAT
~0.5"/150% OF NORMAL) IN PLACE TO SUPPORT A PERIOD OF WIDESPREAD
PRECIPITATION ACROSS PRIMARILY SW MT WITH SEVERAL INCHES OF SNOW
ACROSS THE GALLATIN/MADISON/CENTENNIAL RANGES. TEMPERATURES COOL
BACK TO NEAR OR SLIGHTLY COOLER THAN AVERAGE FRIDAY/SATURDAY AND
LOOK TO REMAIN NEAR SEASONAL AVERAGES GOING INTO EARLY NEXT WEEK
WITH THE NEXT PACIFIC TROUGH AND ASSOCIATED MOISTURE/PRECIPITATION
MOVING INTO THE AREA LATE THIS WEEKEND OR EARLY NEXT WEEK.
- FORECAST CONFIDENCE & SCENARIOS:
THE RISK FOR STRONG WINDS LATE WEDNESDAY IS MAINLY CONFINED TO THE
MADISON RIVER VALLEY AND ADJACENT TERRAIN WITH PROBABILITIES FOR
SUSTAINED WINDS >40MPH OR GUSTS >55MPH AS HAS AS 70% OVER NORRIS
HILL AND AROUND 50% NEAR ENNIS AND FURTHER SOUTH UP THE VALLEY.
PROBABILITIES FOR PRECIPITATION AMOUNTS IN EXCESS OF 0.10" THURSDAY
NIGHT/FRIDAY RANGE FROM 10% OR LESS ALONG THE HI-LINE TO 30-50%
ACROSS CENTRAL MT AND 80% OR HIGHER ALONG/SOUTH OF I-90. SNOW
ACCUMULATION IN EXCESS OF 4" IS LIKELY (60-80%) ACROSS THE
MADISON/GALLATIN/CENTENNIAL RANGES DURING THIS PERIOD WITH ADJACENT
MOUNTAINS AREAS INCLUDING BOZEMAN PASS AND MONIDA PASS HAVING 60% OR
HIGHER RISK OF 2" OR GREATER SNOWFALL WHILE THE RISK FOR SIMILAR
AMOUNTS IN THE BOZEMAN AREA IS 30% OR LESS. HOENISCH
AVIATION
11/06Z TAF PERIOD
VFR CONDITIONS WILL PREVAIL DURING ALL OF THIS TAF PERIOD AT ALL
TERMINALS. WINDS WILL BE LIGHT DURING THE BEGINNING OF THIS
TERMINAL, INCREASE IN THE MIDDLE, AND BE LIGHT AT THE END OF THIS
TAF PERIOD ACROSS ALL TERMINALS EXCEPT FOR THE KEKS AND KHLN
TERMINALS. MID-LEVEL CLOUDS WILL BE AROUND ALL TERMINALS EXCEPT
FOR THE KHVR TERMINAL DURING AT LEAST A PORTION OF THIS TAF
PERIOD. AT THE KLWT TERMINAL THERE IS A 10 - 20% CHANCE FOR RAIN
BETWEEN 11/12Z AND 11/16Z. -IG
REFER TO WEATHER.GOV/ZLC FOR MORE DETAILED REGIONAL AVIATION
WEATHER AND HAZARD INFORMATION.
PRELIMINARY POINT TEMPS/POPS
GTF 52 36 58 37 / 10 10 0 10
CTB 47 31 53 30 / 0 10 10 0
HLN 52 33 56 36 / 10 0 0 10
BZN 50 27 53 31 / 10 0 0 10
WYS 43 17 44 28 / 0 0 0 50
DLN 51 30 53 34 / 0 0 0 20
HVR 52 30 56 32 / 10 0 0 0
LWT 48 30 54 36 / 20 10 0 10
TFX WATCHES/WARNINGS/ADVISORIES
NONE.
HTTP://WWW.WEATHER.GOV/GREATFALLS
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page