967
FXUS65 KTFX 010601
AFDTFX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
1201 AM MDT WED JUL 1 2026
KEY MESSAGES
- DAILY ROUNDS OF SCATTERED SHOWERS AND THUNDERSTORMS CONTINUE THROUGH
AT LEAST FRIDAY, MOST WIDESPREAD THIS AFTERNOON AND EVENING.
- DRIER, WARMER, AND BREEZY TO WINDY CONDITIONS MOVE IN FOR
THE HOLIDAY WEEKEND.
- TEMPERATURES WARM FURTHER HEADING INTO EARLY NEXT WEEK,
ALTHOUGH SHOWER AND THUNDERSTORM ACTIVITY LOOKS TO RAMP UP.
DISCUSSION
- METEOROLOGICAL OVERVIEW:
AN INITIAL WAVE OF SHOWERS AND THUNDERSTORMS MOVING THROUGH
CENTRAL MT THIS MORNING WILL SLOWLY DIMINISH AND END AROUND DAWN.
THERE IS ALSO SOME LINGERING SMOKE AND HAZE FROM CANADIAN
WILDFIRES THAT WILL BE CLEARING OUT THIS MORNING AS THE GENERAL
FLOW ALOFT BECOMES WEST AND EVENTUALLY SOUTHWESTERLY. A SHORTWAVE
WILL MOVE THROUGH THIS INCREASINGLY UNSTABLE SOUTHWESTERLY FLOW
AND BRING SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS THIS
AFTERNOON AND EVENING. ML CAPE VALUES WILL BE RUNNING ROUGHLY
BETWEEN 600 AND 1100 J/KG OVER SOUTHWEST MT AND CENTRAL/NORTH-
CENTRAL AREAS EAST OF I15/HIGHWAY 87. THE COMBINATION OF THIS
INSTABILITY WITH BULK SHEAR RUNNING ABOVE 30 KTS WILL BE
SUFFICIENT TO PRODUCE A FEW STRONG TO SEVERE STORMS IN THESE AREAS
WITH STRONG, GUSTY WINDS, HAIL, AND HEAVY DOWNPOURS BEING THE
PRIMARY HAZARDS IN ADDITION TO CLOUD TO GROUND LIGHTNING.
SIMILAR CONDITIONS PREVAIL ON THURSDAY AND FRIDAY WITH WIDELY
SCATTERED SHOWERS AND THUNDERSTORMS, BUT THERE WILL BE A LACK OF A
DEFINED SHORTWAVE AND SHEAR ON THURSDAY AND ON FRIDAY THE
SHORTWAVE POSITIONING LOOKS TO BE A LITTLE TOO FAR EAST FOR
WIDESPREAD ACTIVITY. FLAT RIDGING STARTS TO BUILD IN AND BRING
WARMER TEMPERATURES AND DRIER CONDITIONS FOR THE HOLIDAY WEEKEND;
HOWEVER, A MID-LEVEL TROUGH PASSING NORTH OF THE CANADIAN BORDER
LOOKS STRENGTHEN THE WESTERLY FLOW ALOFT AND COMBINE WITH DEEP
LAYER MIXING FOR BREEZY TO WINDY CONDITIONS. SATURDAY,
INDEPENDENCE DAY, WILL BE THE WINDIEST DAY WITH THE HIGHEST
PROBABILITIES FOR 40 MPH WIND GUSTS OR HIGHER ALONG THE ROCKY
MOUNTAIN FRONT. THE GREATEST IMPACTS FROM THE WINDS WILL BE FOR
HOLIDAY RELATED ACTIVITIES AND FOR OUTDOOR RECREATION. RECENT
RAINFALL AND SURFACE GREENING SHOULD PRECLUDE FIRE WEATHER
CONCERNS DESPITE THE LOW AFTERNOON HUMIDITIES.
MID-LEVEL HEIGHTS CONTINUE TO RISE AND BRING SUMMERLIKE
TEMPERATURES EARLY NEXT WEEK. THE ONLY CAVEAT WILL BE A
SOUTHWESTERLY FLOW ALOFT DEVELOPING AGAIN IN RESPONSE TO A TROUGH
MOVING ONTO THE PACIFIC NW COAST. SHORTWAVES LOOK TO INTERACT WITH
BUILDING INSTABILITY FOR INCREASED SHOWER AND THUNDERSTORM
ACTIVITY NEXT MONDAY AND TUESDAY. THE ECMWF EXTREME FORECAST INDEX
(EFI) IS ALREADY BEGINNING TO HIGHLIGHT UNUSUALLY HIGH CAPE AND
SHEAR AVAILABILITY FOR STRONG TO SEVERE STORMS FOR THESE DAYS
SHOULD THIS PATTERN COME TO FRUITION. - RCG
AVIATION
01/06Z TAF PERIOD
A FEW SCATTERED SHOWERS/THUNDERSTORMS WILL AFFECT THE CWA BEFORE
12Z WED. A SHORT BREAK IN THE PRECIP WILL OCCUR ON WED MORNING,
BEFORE ANOTHER ROUND OF SHOWERS/THUNDERSTORMS AFFECTS SOUTHWEST
AND CENTRAL MT ON WED AFTERNOON/EVENING. SOME STORMS COULD PRODUCE
GUSTY WINDS ON WED AFTERNOON. SMOKE FROM DISTANT FIRES IS NOW
AFFECTING MUCH OF THE CWA FOR DISTANT VISIBILITY. DISTANT
VISIBILITY IS NOW LESS THAN 20 MILES IN SOME AREAS. EXPECT DISTANT
VISIBILITY TO BE AFFECTED ACROSS THE CWA BY CLOUDS/PRECIP/SMOKE
THROUGH THE PERIOD. BRUSDA
HYDROLOGY
ONGOING FLOODING CONTINUES TO BE REPORTED ALONG SWIFT CREEK IN
THE MANY GLACIER AREA, SO THE FLOOD WARNING FOR THAT AREA WAS
EXTENDED THROUGH 430 PM MDT WEDNESDAY. ALL OTHER FLOOD PRODUCTS
WERE LIFTED PER RECEDING WATERS AND NO SIGNIFICANT RAINS EXPECTED
IN THE NEAR TERM. - RCG
PRELIMINARY POINT TEMPS/POPS
GTF 75 51 77 52 / 30 30 0 10
CTB 72 48 73 48 / 20 20 0 0
HLN 73 50 76 51 / 70 60 30 10
BZN 74 46 76 48 / 70 40 10 20
WYS 70 37 72 39 / 10 20 10 0
DLN 71 44 75 46 / 70 40 10 10
HVR 79 53 80 52 / 20 40 10 10
LWT 74 47 74 48 / 50 60 40 10
TFX WATCHES/WARNINGS/ADVISORIES
NONE.
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