915
FXUS65 KTFX 141138
AFDTFX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
538 AM MDT SUN JUN 14 2026
AVIATION SECTION UPDATED.
KEY MESSAGES
- A WARMING TREND CONTINUES THROUGH TUESDAY, ALTHOUGH WEAK
PASSING WEATHER SYSTEMS MAY BRING A FEW ISOLATED SHOWERS OR
STORMS FOR NORTHERN AREAS TONIGHT THROUGH EARLY TUESDAY.
- WARM AND WINDY CONDITIONS DEVELOP ON TUESDAY FOLLOWED BY PERIODS
OF SHOWERS AND THUNDERSTORMS AND MORE GUSTY WINDS TUESDAY
EVENING THROUGH WEDNESDAY.
- GENERAL UNSETTLED CONDITIONS CONTINUE FOR THE SECOND HALF OF
NEXT WEEK WITH MORE OPPORTUNITIES FOR SHOWERS AND STORMS.
DISCUSSION
/ISSUED 329 AM MDT SUN JUN 14 2026/
- METEOROLOGICAL OVERVIEW:
NORTHWESTERLY FLOW ALOFT GENERALLY REMAINS IN PLACE THROUGH THE
END OF THE WORKWEEK. THE EASTERN PERIPHERY OF A STRENGTHENING
PACIFIC RIDGE WILL BRING A WARMING TREND OVER THE NORTHERN ROCKIES
THROUGH TUESDAY. ALTHOUGH DRY CONDITIONS GENERALLY PREVAIL, THERE
WILL BE A FEW WEAK SHORTWAVES THAT BRING A FEW ISOLATED SHOWERS
OR STORMS, MOSTLY ALONG THE HI-LINE TONIGHT THROUGH TUESDAY.
WESTERLY FLOW ALOFT INCREASES LATE MONDAY INTO TUESDAY IN ADVANCE
OF AN APPROACHING SHORTWAVE AND ATTENDANT COLD FRONT WITH
H850/H700 WINDS INCREASING TO THE 40 TO 50 KT RANGE BY TUESDAY
EVENING. THIS WILL BRING WINDY AND DRY CONDITIONS TUESDAY
AFTERNOON WHILE TEMPERATURES SURGE WELL INTO THE 80S. A CANADIAN
COLD FRONT MOVES SOUTHWARD SOMETIME TUESDAY EVENING THROUGH EARLY
WEDNESDAY AND SENDS A WAVE OF SHOWERS AND THUNDERSTORMS THROUGH
THE FORECAST AREA, MOST NUMEROUS OVER CENTRAL/NORTH-CENTRAL MT.
CAPE VALUES FOR THIS TIME PERIOD LOOK TO REMAIN ONLY AROUND A FEW
HUNDRED J/KG; HOWEVER, BULK SHEAR WILL GENERALLY BE OVER 40 KTS SO
THERE WILL BE AT LEAST LOCALIZED STRONG WIND GUSTS, SOME HAIL,
AND DOWNPOURS WITH THIS ACTIVITY.
GUSTY NORTHWESTERLY WINDS AND SCATTERED SHOWER/THUNDERSTORM
ACTIVITY LINGER ON THE BACKSIDE OF THIS SYSTEM THROUGH WEDNESDAY
EVENING AND GENERAL UNSETTLED CONDITIONS CONTINUE FOR THE
REMAINDER OF THE SECOND HALF OF THE WEEK. SHOWER AND THUNDERSTORM
ACTIVITY LOOKS TO RAMP UP AGAIN FOR THE WEEKEND WITH CAPE VALUES
APPROACHING THE 1,000 J/KG AT TIMES AND SUBTLE SHORTWAVES
PROVIDING SUFFICIENT FORCING FOR STRONGER CONVECTIVE INITIATION.
- RCG
- FORECAST CONFIDENCE & SCENARIOS:
WINDY CONDITIONS AND THUNDERSTORMS TUESDAY AND WEDNESDAY...
WESTERLY WINDS INCREASE ON TUESDAY IN ADVANCE OF AN APPROACHING
TROUGH AND COLD FRONT. THE NAEFS ANOMALY INDEX CONTINUES TO
ADVERTISE H700/H500 WINDS APPROACHING THREE STANDARD DEVIATIONS
ABOVE CLIMATOLOGY. NBM PROBABILITIES FOR 50 MPH + GUSTS CONTINUE
TO RUN IN THE 60 TO 80% RANGE ALONG THE ROCKY MOUNTAIN
FRONT/PLAINS WEST OF I15 TUESDAY AFTERNOON, BUT THE SWATH OF
SIMILAR PROBABILITIES OVER CENTRAL AND SOUTHWEST MT HAVE BECOME
MORE WIDESPREAD TUESDAY EVENING/NIGHT.
THE MOST RELEVANT UNCERTAINTIES CONTINUE TO BE THE TIMING OF THE
STRONGEST WINDS ALOFT AND WHETHER THEY WILL MOVE THROUGH DURING
PEAK DIURNAL MIXING OR LATER IN THE EVENING WITH LESS MOMENTUM
TRANSFER. THE CANADIAN COLD FRONT AND ANY PRE-FRONTAL NORTHERLY
WINDS SHIFTS WILL ALSO AFFECT WIND MAGNITUDE AND DURATION FOR
NORTHERN AREAS, ESPECIALLY AREAS ALONG THE NORTHERN ROCKY MOUNTAIN
FRONT. THE TIMING OF SHOWERS AND THUNDERSTORMS WILL ALSO BE
HIGHLY DEPENDENT ON THE FRONTAL PASSAGE. THUNDERSTORM HAZARDS,
INCLUDING LOCALIZED STRONG WIND GUSTS, HAIL, AND DOWNPOURS WILL BE
MOST WIDESPREAD OVER CENTRAL/NORTH-CENTRAL MT TUESDAY EVENING,
ESPECIALLY ALONG THE HI- LINE.
THE WINDS WILL SHIFT TO A MORE NORTHWESTERLY DIRECTION ON
WEDNESDAY AND WILL GENERALLY BE STRONGEST OVER THE PLAINS EAST OF
I15, ESPECIALLY ALONG THE HI-LINE AND OVER PORTIONS OF FERGUS
COUNTY. SHOWERS AND THUNDERSTORMS WILL MOSTLY BE CONCENTRATED OVER
CENTRAL/NORTH-CENTRAL MT AGAIN AND WILL GENERALLY BE WEAK;
HOWEVER, THEY WILL BE CAPABLE OF TRANSFERRING THE STRONGER 40 TO
50 KT H700 WINDS TO THE SURFACE.
THE PRIMARY IMPACT FROM THESE WINDS AND SHOWER/THUNDER ACTIVITY
STILL LOOKS BE INCLEMENT OUTDOOR RECREATION AND DIFFICULT TRAVEL
FOR THOSE OPERATING HIGH PROFILE VEHICLES. ALSO, THE COMBINATION
OF TEMPERATURES WARMING WELL INTO THE 80S AND RHS FALLING TO NEAR
CRITICALLY LOW LEVELS ON TUESDAY WILL ALSO BE MONITORED FOR FIRE
WEATHER CONCERNS, ALTHOUGH FUELS WILL BE LESS RECEPTIVE GIVEN THE
RECENT RAINFALL AND GREENUP. AREAS THAT HAVE MISSED OUT ON THE
RAINFALL, LIKE SOUTHWEST MT, WILL BE MONITORED FOR ELEVATED FIRE
CONCERNS. - RCG
AVIATION
14/12Z TAF PERIOD
VFR CONDITIONS GENERALLY PREVAIL, BUT WEAK DISTURBANCES MAY BRING
SCATTERED TO BROKEN MOSTLY MID- LEVEL CLOUDINESS AT TIMES AND EVEN
A FEW SPOTTY SHOWERS. THIS WILL BE MOST PRONOUNCED ALONG THE HI-
LINE BETWEEN 15/06 AND 15/12Z. - RCG
PRELIMINARY POINT TEMPS/POPS
GTF 71 45 78 55 / 0 0 10 0
CTB 71 45 78 57 / 0 10 10 10
HLN 73 44 80 55 / 0 0 0 0
BZN 70 39 77 48 / 0 0 0 0
WYS 68 32 75 38 / 0 0 0 0
DLN 69 40 79 48 / 0 0 0 0
HVR 74 46 78 52 / 0 10 20 10
LWT 68 41 71 49 / 0 10 10 0
TFX WATCHES/WARNINGS/ADVISORIES
NONE.
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