419
FXUS65 KTFX 010719
AFDTFX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
119 AM MDT SAT AUG 1 2026
KEY MESSAGES
- AFTER A HOT DAY TODAY, TEMPERATURES TREND COOLER INTO SUNDAY
BEHIND A COLD FRONT.
- CRITICAL FIRE WEATHER CONDITIONS DEVELOP THIS AFTERNOON,
PERSISTING INTO SUNDAY.
- AFTER A BRIEFLY COOLER STRETCH BEHIND THE COLD FRONT,
TEMPERATURES TREND BACK WARMER MID-WEEK.
DISCUSSION
- METEOROLOGICAL OVERVIEW:
STRONG UPPER LEVEL RIDGING IN PLACE ACROSS THE REGION WILL QUICKLY
BE USHERED EASTWARD THROUGH THE DAY TODAY AS AN UPPER LEVEL TROUGH
SLIDES EAST NEAR THE INTERNATIONAL BORDER. AHEAD OF THE APPROACHING
TROUGH TEMPERATURES RISE WELL INTO THE 90S ACROSS THE REGION,
REACHING AS HIGH AS 110F OR SO IN TYPICALLY HEAT PRONE AREAS. THE
ONGOING EXTREME HEAT WARNINGS AND HEAT ADVISORIES ARE UNCHANGED
WITH THIS UPDATE. THOSE WITH PLANS OUTSIDE TODAY SHOULD PLAN FOR
NUMEROUS BREAKS AND FOR PLENTY OF HYDRATION.
A DRY COLD FRONT ARRIVES AS THE UPPER LEVEL TROUGHING MOVES EASTWARD
THIS AFTERNOON. AHEAD OF THE FRONT, BREEZY SOUTHWESTERLY WINDS
LOOK TO DEVELOP IN MANY AREAS, TRANSITIONING TO A MORE
NORTHWESTERLY DIRECTION BEHIND THE FRONT LATE AFTERNOON AND INTO
THE EVENING. THE STRONGEST CROSS BARRIER FLOW ALOFT HOLDS OFF TIL
THIS EVENING AND TONIGHT, PEAKING IN EXCESS OF 60 KTS ALONG THE
NORTHERN ROCKY MOUNTAIN FRONT. THE COMBINATION OF COOLING
TEMPERATURES NEAR THE SURFACE BEHIND THE FRONT AND STILL MILD
TEMPERATURES ALOFT WILL RESULT IN SOME RIDGETOP STABILITY TONIGHT
ALONG THE ROCKY MOUNTAIN FRONT. THIS WILL AID IN TRANSLATING THE
AFOREMENTIONED STRONGER WINDS ALOFT TO THE SURFACE IN THESE AREAS
VIA MOUNTAIN WAVE ACTIVITY. THE STRONGEST WINDS ALOFT FADE QUICKLY
AFTER SUNRISE SUNDAY, THOUGH THE CONTINUED BRISK WESTERLY FLOW
ALOFT WILL KEEP GUSTY WINDS AROUND THROUGH THE DAY SUNDAY.
A QUICK MOVING TROUGH IN WAKE OF THE INITIAL TROUGHING THAT WILL BE
EXITING EASTWARD BY SUNDAY AFTERNOON MOVES ACROSS THE AREA SUNDAY
NIGHT. THIS TROUGH LOOKS TO HAVE ENOUGH MOISTURE ASSOCIATED WITH
IT TO RESULT IN A BRIEF STRETCH OF LIGHT PRECIPITATION ALONG THE
NORTHERN ROCKY MOUNTAIN FRONT SUNDAY EVENING AND OVERNIGHT.
TEMPERATURES ALOFT LOOK TO BE QUITE COOL, WHICH WILL YIELD THE
RISK FOR SOME LIGHT SNOW NEAR MOUNTAIN PEAKS IN GLACIER NP OVER
THIS TIMEFRAME.
A COOLER NORTHWESTERLY FLOW ALOFT PERSISTS INTO THE EARLY WEEK ACROSS
THE REGION, RESULTING IN A BELOW AVERAGE TEMPERATURES ACROSS THE
REGION FOR A COUPLE DAYS. THIS TREND LOOKS TO BE SHORT-LIVED HOWEVER,
AS TEMPERATURES BEGIN TO TREND WARMER BY MID-WEEK. -AM
- FORECAST CONFIDENCE & SCENARIOS:
STRONG WINDS TONIGHT:
RIDGETOP STABILITY WILL YIELD A GOOD SETUP FOR TRANSLATING STRONGER
WINDS TO THE SURFACE TONIGHT NEAR THE ROCKY MOUNTAIN FRONT. GIVEN
THE STRONGEST WINDS ALOFT CONTINUE TO TAKE AIM AT THE NORTHERN ROCKY
MOUNTAIN FRONT, AND LARGELY ONLY NICK THE SOUTHERN ROCKY MOUNTAIN
FRONT, NO CHANGES ARE BEING MADE TO THE ONGOING HIGH WIND WARNING.
SHOULD THE STRONGER WINDS ALOFT TREND MUCH FURTHER SOUTHWARD,
ADDITIONAL HIGH WIND WARNINGS MAY BECOME NECESSARY NEAR THE SOUTHERN
ROCKY MOUNTAIN FRONT. -AM
AVIATION
01/06Z TAF PERIOD
VFR CONDITIONS WILL PREVAIL ACROSS ALL TERMINALS DURING THIS TAF
PERIOD. HOWEVER, SMOKE FROM WILDFIRES HAS BEEN PERIODICALLY REDUCING
VISIBILITY AT THE KCTB AND KHVR TERMINALS THIS EVENING AND WILL
CONTINUE TO DO SO THROUGH AT LEAST 01/10Z. ACROSS ALL TERMINALS
AFTER 01/18Z WINDS WILL BEGIN TO INCREASE WITH THE STRONGEST WINDS
BEING AT THE KCTB TERMINAL. AT THE KCTB TERMINAL BY THE END OF THIS
TAF PERIOD WINDS WILL GUST IN EXCESS OF 40 KT. ACROSS MOST OF THE
TAF SITES SMOKE FROM WILDFIRES WILL REDUCE SLANTWISE VISIBILITY
DURING THIS TAF PERIOD. AT THE KCTB TERMINAL THERE WILL BE
ISOLATED INSTANCES OF LOW-LEVEL WIND SHEAR AT THE VERY END OF
THIS TAF PERIOD. -IG
FOR KGTF: WINDS WILL BE LIGHT THROUGH 18Z. BETWEEN 18Z AND 23Z
WINDS WILL INCREASE AND SHIFT FROM THE SOUTHWEST TO THE WEST.
BETWEEN 21Z AND 00Z THERE IS A 70% CHANCE FOR A 15 KT CROSSWIND.
-IG
FIRE WEATHER
CRITICAL FIRE WEATHER CONDITIONS ARE FORECAST THIS WEEKEND ACROSS
ALL FIRE WEATHER DISTRICTS.
GUSTY WINDS DEVELOPING THIS AFTERNOON AHEAD OF A DRY COLD FRONT WILL
COMBINE WITH RELATIVE HUMIDITIES APPROACHING SINGLE DIGITS TO RESULT
IN CRITICAL FIRE WEATHER CONDITIONS IN MOST AREAS. WINDS SHIFT TO A
MORE NORTHWESTERLY DIRECTION THIS AFTERNOON AND EVENING BEHIND THE
COLD FRONT. WHILE GUSTY WINDS DIMINISH SOMEWHAT OUT OVER THE PLAINS
TONIGHT, STRONG WINDS WILL DEVELOP ALONG THE ROCKY MOUNTAIN FRONT
THIS EVENING, SLOWLY EXPANDING OVER THE PLAINS THROUGH THE NIGHT AND
INTO THE DAY SUNDAY. OVERNIGHT HUMIDITY RECOVERY IS FORECAST TO BE
NEARLY NON-EXISTENT WHERE THESE WINDS ARE PERSISTENT OVERNIGHT NEAR
THE ROCKY MOUNTAIN FRONT.
ALTHOUGH COOLER TEMPERATURES WILL BE MOVING IN BEHIND THE COLD FRONT
FOR SUNDAY, VERY LOW RELATIVE HUMIDITY WILL PERSIST (APPROACHING
SINGLE DIGITS ONCE AGAIN). COMBINE THIS WITH FORECAST BREEZY
WINDS, AND CRITICAL FIRE WEATHER CONDITIONS WILL BE AROUND ONCE
AGAIN FOR SUNDAY. -AM
PRELIMINARY POINT TEMPS/POPS
GTF 103 63 85 50 / 0 0 0 0
CTB 97 55 75 45 / 0 0 0 0
HLN 100 60 84 50 / 0 0 0 0
BZN 101 57 90 49 / 0 0 0 0
WYS 91 48 86 40 / 0 0 0 0
DLN 95 55 88 47 / 0 0 0 0
HVR 106 62 86 48 / 0 0 0 0
LWT 101 61 85 49 / 0 0 0 30
TFX WATCHES/WARNINGS/ADVISORIES
RED FLAG WARNING FROM NOON TODAY TO 9 PM MDT SUNDAY FOR CENTRAL
AND EASTERN LEWIS AND CLARK NATIONAL FOREST AREAS-CHOUTEAU AND
FERGUS COUNTIES-EASTERN GLACIER/TOOLE/CENTRAL/EASTERN
PONDERA/LIBERTY-HELENA AND TOWNSEND RANGER DISTRICTS OF THE
HELENA NATIONAL FOREST-HILL AND BLAINE COUNTIES-LEWIS AND CLARK
NATIONAL FOREST ROCKY MOUNTAIN DISTRICT-ROCKY MOUNTAIN FRONT-
LINCOLN RANGER DISTRICT OF THE HELENA NATIONAL FOREST.
HEAT ADVISORY FROM NOON TODAY TO 3 AM MDT SUNDAY FOR BEAVERHEAD
AND WESTERN MADISON BELOW 6000FT-CANYON FERRY AREA-EASTERN
GLACIER, WESTERN TOOLE, AND CENTRAL PONDERA-EASTERN PONDERA AND
EASTERN TETON-EASTERN TOOLE AND LIBERTY-ELKHORN AND BOULDER
MOUNTAINS-GATES OF THE MOUNTAINS-HELENA VALLEY-HILL COUNTY-
MEAGHER COUNTY VALLEYS-MISSOURI HEADWATERS-NORTHERN BLAINE
COUNTY-SNOWY AND JUDITH MOUNTAINS.
HIGH WIND WARNING FROM 6 PM THIS EVENING TO NOON MDT SUNDAY FOR
EAST GLACIER PARK REGION-EASTERN GLACIER, WESTERN TOOLE, AND
CENTRAL PONDERA-NORTHERN HIGH PLAINS.
EXTREME HEAT WARNING FROM NOON TODAY TO NOON MDT SUNDAY FOR
BEARS PAW MOUNTAINS AND SOUTHERN BLAINE-FERGUS COUNTY BELOW
4500FT-WESTERN AND CENTRAL CHOUTEAU COUNTY.
EXTREME HEAT WARNING FROM NOON TODAY TO 3 AM MDT SUNDAY FOR
CASCADE COUNTY BELOW 5000FT-GALLATIN VALLEY-JUDITH BASIN COUNTY
AND JUDITH GAP-MADISON RIVER VALLEY.
HTTP://WWW.WEATHER.GOV/GREATFALLS
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page