916
FXUS65 KTFX 211446
AFDTFX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
846 AM MDT SUN JUN 21 2026
KEY MESSAGES
- COOLER AND WETTER CONDITIONS ARE EXPECTED TO CONTINUE THROUGH
MONDAY WITH DRIER AND MILD CONDITIONS ON TUESDAY.
- WARMER TEMPERATURES EXPECTED MID TO LATE WEEK.
- POTENTIAL FOR ANOTHER STORM SYSTEM ARRIVING THIS WEEKEND.
UPDATE
845 AM UPDATE...UPDATED FORECAST IS OUT. JUST ADJUSTED POP/SKY
CONDITIONS TOWARDS CURRENT TRENDS AS SHOWERS HAVE DIMINISHED THIS
MORNING. SHOWERS/THUNDERSTORMS WILL REDEVELOP THIS AFTERNOON AS
AIRMASS BECOMES A BIT UNSTABLE. THE REST OF THE FORECAST IS ON
TRACK. BRUSDA
/ISSUED 130 AM MDT SUN JUN 21 2026/
STRONG PRESSURE RISES IN WAKE OF A COLD FRONT COMBINED WITH A
BARRIER JET ALONG AND WEST OF THE I-15 CORRIDOR IS HELPING TO
SUPPORT STRONG AND GUSTY NORTHWEST TO NORTH WINDS OVER PORTIONS OF
THE PLAINS EARLY THIS MORNING. THESE WINDS WILL GRADUALLY SUBSIDE
THROUGH SUNRISE AND SPREAD FURTHER SOUTH AND EAST ACROSS THE
REMAINDER OF NORTH CENTRAL THROUGH SOUTHWEST MONTANA. THE
FORECAST HAS BEEN UPDATED TO REFLECT THE THESE TRENDS. - MOLDAN
DISCUSSION
/ISSUED 100 AM MDT SUN JUN 21 2026/
- METEOROLOGICAL OVERVIEW:
A RELATIVELY WEAK DISTURBANCE WILL TRACK ALONG THE CANADIAN BORDER
THROUGH SUNDAY MAINTAINING THE COOLER TEMPERATURES AND INTRODUCING
ANOTHER CHANCE FOR AFTERNOON SHOWERS AND THUNDERSTORMS MAINLY ACROSS
NORTH-CENTRAL MONTANA. THIS DISTURBANCE SLOWLY MAKES ITS WAY EAST
MONDAY AND TUESDAY LEAVING OUR AREA IN NORTHWESTERLY FLOW DURING
THIS TIME. TEMPERATURES WILL REMAIN NEAR TO BELOW AVERAGE ACROSS THE
REGION WITH PRECIPITATION CHANCES CONTINUING THROUGH MONDAY EVENING.
STARTING WEDNESDAY, UPPER-LEVEL RIDGING STARTS TO BUILD OVER THE
WESTERN CONUS ALLOWING FOR A WARM UP THAT IS EXPECTED TO LAST
THROUGH THE REMAINDER OF THE WORK WEEK. THERE IS MODERATE AGREEMENT
IN ANOTHER STORM SYSTEM ARRIVING NEXT WEEKEND, ALTHOUGH THE FINER
DETAILS OF HOW IT WILL TRACK ACROSS OUR REGION REMAIN UNCLEAR AT
THIS TIME.
- FORECAST CONFIDENCE & SCENARIOS:
SUNDAY/MONDAY SHOWERS: GENERALLY LIGHT PRECIPITATION IS EXPECTED
WITH ANY SHOWER OR THUNDERSTORM THAT DEVELOPS. THERE COULD BE A
COUPLE THAT PRODUCE WIND GUSTS IN EXCESS OF 45 MPH BUT OTHERWISE THE
THREAT FOR STRONG STORMS IS VERY LOW THROUGH THE START OF THE WEEK.
THE HIGHEST PRECIPITATION CHANCES WILL BE NORTH OF A LINE BETWEEN
HELENA AND WHITE SULPHUR SPRINGS WITH ACCUMULATION AMOUNTS GENERALLY
EXPECTED TO STAY UNDER 0.10".
THURSDAY/FRIDAY HEAT: ON THURSDAY THERE IS A GREATER THAN 70% CHANCE
FOR HIGHS EXCEEDING 80 DEGREES ACROSS THE LOWER ELEVATIONS.
ADDITIONALLY, THERE IS A 60% CHANCE FOR SOME LOCATIONS INCLUDING
GREAT FALLS, FORT BENTON, HELENA, AND BOZEMAN EXCEEDING 85 DEGREES
ON THURSDAY. FRIDAY CURRENTLY LOOKS TO BE SLIGHTLY COOLER WITH A 60%
CHANCE FOR HIGHS EXCEEDING 80 DEGREES ALONG THE LOWER ELEVATIONS AND
A 50% CHANCE FOR HIGHS EXCEEDING 85 DEGREES ACROSS PORTIONS OF
CHOUTEAU AND FERGUS COUNTY AS WELL AS THE GALLATIN VALLEY. -THOR
AVIATION
21/12Z TAF PERIOD
MVFR CIGS OVER THE PLAINS OF CENTRAL AND NORTH CENTRAL WILL
GRADUALLY RISE TO LOW-VFR/VFR THROUGH 15-18Z, WITH ISOLATED TO
WIDELY SCATTERED DISSIPATING THROUGH 12-15Z THIS MORNING.
ADDITIONAL SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED TO
REDEVELOP THIS AFTERNOON AND PERSIST INTO THE EVENING HOURS
TONIGHT, BUT LOW-VFR/VFR CONDITIONS ARE STILL EXPECTED TO
PREVAIL. OCCASIONAL MOUNTAIN OBSCURATION CAN BE EXPECTED DURING
THE 2112/2212 TAF PERIOD. - MOLDAN
PRELIMINARY POINT TEMPS/POPS
GTF 74 48 67 44 / 20 20 10 0
CTB 69 43 62 40 / 30 50 10 0
HLN 80 50 72 45 / 10 0 20 0
BZN 78 46 74 42 / 10 10 0 0
WYS 70 37 72 35 / 20 40 0 0
DLN 77 45 75 43 / 10 10 0 0
HVR 75 46 68 44 / 20 40 30 10
LWT 71 44 64 41 / 20 50 50 10
TFX WATCHES/WARNINGS/ADVISORIES
NONE.
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