883
FXUS65 KTFX 141839
AFDTFX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
ISSUED BY NATIONAL WEATHER SERVICE MISSOULA MT
1239 PM MDT TUE JUL 14 2026
KEY MESSAGES
- SLIGHT RISK FOR SEVERE THUNDERSTORMS ACROSS PORTIONS OF CENTRAL
AND NORTH CENTRAL MONTANA, WITH THE PRIMARY SEVERE WEATHER
THREATS BEING HAIL LARGER THAN QUARTER SIZE AND DAMAGING WIND
IN EXCESS OF 60 MPH.
- MARGINAL RISK FOR FLASH FLOODING ACROSS PORTIONS OF SOUTHWEST
THROUGH NORTH CENTRAL, MOST NOTABLY ALONG AND NEAR THE THE
MONTANA HWY 200 CORRIDOR.
- MOISTURE CIRCULATING ACROSS THE NORTHERN ROCKIES AND MT WILL
MAINTAIN DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS THROUGH
THE UPCOMING WEEKEND.
DISCUSSION
THE NORTHERN ROCKIES AND MT REMAIN ON THE NW PERIPHERY OF AN
EXPANSIVE MID-UPPER LEVEL RIDGE CENTERED ON THE N-CENTRAL CONUS. A
PLUME OF SUBTROPICAL SOURCED MID-UPPER LEVEL MOISTURE CIRCULATING
AROUND THE BACK SIDE OF THE RIDGE WILL CONTINUE TO DEEPEN TODAY
WITH LOWER LEVEL EASTERLY FLOW BRINGING DEWPOINTS IN THE 50S TO
AROUND 60 TO CENTRAL/NORTH-CENTRAL MT OVERNIGHT. AN EMBEDDED MID-
LEVEL SHORTWAVE AND UPPER LEVEL JET DISTURBANCE LIFTING OUT OF
NORTHERN CA WILL HELP TO TRIGGER AND ORGANIZE THUNDERSTORM
DEVELOPMENT ACROSS SW MT THIS AFTERNOON WITH STRONGER CELLS
TRACKING N/NE THROUGH CENTRAL MT AND EASTERN PORTIONS OF N-CENTRAL
MT THIS EVENING. THE PRESENCE OF DEEP MOISTURE AND MODERATE SHEAR
WILL SUPPORT SOME STRONG TO SEVERE THUNDERSTORMS WITH STRONG
WINDS AND HAIL POSSIBLE IN ADDITION TO LOCALIZED HEAVY RAINFALL AS
STORMS PEAK IN INTENSITY EARLY THIS EVENING.
THE FLOW OF ANOMALOUS MOISTURE ACROSS THE AREA LOOKS TO REMAIN IN
PLACE THROUGH THE UPCOMING WEEKEND, MAINTAINING A DAILY CHANCE
FOR SHOWERS AND THUNDERSTORMS. CLOUD-COVER ON WEDNESDAY WILL
RESULT IN TEMPERATURES CLOSER TO SEASONAL AVERAGES AND MAY
INHIBIT INSTABILITY AND RESULT IN A LOWER COVERAGE OF
SHOWERS/STORMS. DIFFERENCES IN THE TIMING OF EMBEDDED DISTURBANCES
AND THE EXTENT CLOUD-COVER AND INSTABILITY LEADS TO LOWER
CONFIDENCE IN SPECIFIC DETAILS BEYOND WEDNESDAY. HOENISCH
AVIATION
14/18Z TAF PERIOD
SHOWERS AND THUNDERSTORMS WILL DEVELOP THROUGH THE AFTERNOON HOURS
ACROSS THE HIGHER TERRAIN OF CENTRAL IDAHO AND SOUTHWEST MONTANA
BEFORE LIFTING NORTH TO NORTHEAST IN CENTRAL AND PORTIONS OF NORTH
CENTRAL MONTANA. THUNDERSTORMS MOVING INTO CENTRAL MONTANA LATE
THIS AFTERNOON AND EARLY THIS EVENING WILL BE CAPABLE OF
PRODUCING LARGE HAIL, DAMAGING WINDS, AND HEAVY RAINFALL THAT
WILL LEAD TO REDUCED VIS. THOSE TERMINALS MOST AT RISK OF THESE
STRONG STORMS WILL BE THE KHLN, KGTF, KLWT AND KHVR. WHILE VFR
CONDITIONS WILL LARGELY PREVAIL THERE WILL BE PERIOD OF MVFR/LOW-
VFR CONDITIONS THIS AFTERNOON AND EVENING BENEATH SHOWERS AND
STORMS, WITH BRIEF PERIODS OF IFR POSSIBLE. MOUNTAIN OBSCURATION
WILL INCREASE THROUGH THE REMAINDER OF THE DAY. - MOLDAN
HYDROLOGY
A FLASH FLOOD WATCH REMAINS IN PLACE FOR MUCH OF CENTRAL MT AND
ADJOINING AREAS FOR THIS AFTERNOON AND EVENING. HIGH-RESOLUTION
MODEL ENSEMBLES ARE IN FAIRLY GOOD AGREEMENT FOCUSING STRONGER
CONVECTION AND POTENTIAL FOR INTENSE RAINFALL RATES ALONG AN AXIS
FROM SOUTHERN LEWIS AND CLARK COUNTY EAST ACROSS THE BIG/LITTLE
BELTS, JUDITH BASIN AND FERGUS COUNTIES WHERE THERE IS 50-80%
PROBABILITY OF 1HR RAINFALL RATES EXCEEDING .50" AND 30-50%
PROBABILITY FOR LOCALIZED HOURLY RATES EXCEEDING 1". THIS PUTS THE
HORSE GULCH BURN SCAR AT RISK FOR FLASH FLOODING AS WELL AS OTHER
AREAS THAT MAY SEE THESE TYPES OF INTENSE RAINFALL RATES. STORMS
ARE EXPECTED TO HAVE REASONABLY QUICK MOTION, WHICH MAY HELP TO
KEEP INTENSE RAINFALL RATES RELATIVELY BRIEF BUT STILL IMPACTFUL.
HOENISCH
PRELIMINARY POINT TEMPS/POPS
GTF 59 82 59 88 / 90 50 20 20
CTB 56 79 57 83 / 50 30 30 30
HLN 62 86 62 90 / 60 60 30 30
BZN 58 86 57 91 / 40 50 40 30
WYS 52 84 49 87 / 10 30 30 10
DLN 56 85 55 89 / 20 50 30 10
HVR 60 82 58 89 / 80 50 30 0
LWT 55 79 54 85 / 90 70 40 40
TFX WATCHES/WARNINGS/ADVISORIES
FLOOD WATCH UNTIL MIDNIGHT MDT TONIGHT FOR BEARS PAW MOUNTAINS
AND SOUTHERN BLAINE-BIG BELT, BRIDGER AND CASTLE MOUNTAINS-
CANYON FERRY AREA-CASCADE COUNTY BELOW 5000FT-ELKHORN AND
BOULDER MOUNTAINS-FERGUS COUNTY BELOW 4500FT-GALLATIN VALLEY-
GATES OF THE MOUNTAINS-HELENA VALLEY-JUDITH BASIN COUNTY AND
JUDITH GAP-LITTLE BELT AND HIGHWOOD MOUNTAINS-MEAGHER COUNTY
VALLEYS-MISSOURI HEADWATERS-SNOWY AND JUDITH MOUNTAINS-SOUTHERN
HIGH PLAINS-UPPER BLACKFOOT AND MACDONALD PASS-WESTERN AND
CENTRAL CHOUTEAU COUNTY.
HTTP://WWW.WEATHER.GOV/GREATFALLS
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