206
FXUS65 KTFX 070433
AFDTFX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
1033 PM MDT MON JUL 6 2026
AVIATION SECTION UPDATED.
KEY MESSAGES
- DAILY CHANCES OF SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY, A
FEW MAY BECOME SEVERE.
- HEAVY RAIN IS POSSIBLE MONDAY AND TUESDAY WHICH MAY LEAD TO
ISOLATED FLASH FLOODING.
- MUCH WARMER AND DRIER CONDITIONS TOWARDS THE END OF THE WEEK
AND THROUGH THE WEEKEND.
DISCUSSION
/ISSUED 610 PM MDT MON JUL 6 2026/
- METEOROLOGICAL OVERVIEW:
A SHORTWAVE COMBINED WITH MOIST SOUTHWESTERLY FLOW WILL CONTINUE
TO MAKE ITS WAY ACROSS THE REGION TODAY THROUGH TOMORROW. A FEW
MAY BECOME SEVERE BUT THE MAIN THREAT WILL BE HEAVY RAIN WHICH MAY
LEAD TO LOCALIZED FLASH FLOODING. WEAK TRANSIENT RIDGING WILL
PASS THROUGH ON TUESDAY WITH LEFT OVER MOISTURE AND INSTABILITY
POTENTIALLY BEING ENOUGH TO KICK OFF SOME AFTERNOON SHOWERS AND
THUNDERSTORMS, ESPECIALLY IN NORTH- CENTRAL MONTANA. AN UPPER-
LEVEL TROUGH MAKES ITS WAY ACROSS SOUTHERN CANADA WEDNESDAY INTO
THURSDAY. WHILE THE BULK OF THE INSTABILITY IS EXPECTED TO STAY IN
CANADA THERE IS STILL A CHANCE FOR AFTERNOON SHOWERS AND
THUNDERSTORMS WITH A FEW THAT MAY BE STRONG TO SEVERE.
HEADING TOWARDS THE WEEKEND UPPER-LEVEL RIDGING BUILDS OVER THE
WESTERN CONUS LEADING TO MUCH WARMER TEMPERATURES ACROSS THE
STATE.
- FORECAST CONFIDENCE & SCENARIOS:
TODAY AND TOMORROW: SCATTERED SHOWERS IN SOUTHWEST MONTANA WILL
CONTINUE TO SPREAD FURTHER NORTH AS THE AFTERNOON GOES ON. THE
LATEST HI-RES MODEL RUNS POINT TOWARDS A CLUSTER OF STORMS FORMING
IN IDAHO AND MOVING UP TO THE NORTHEAST THROUGH OUR REGION THIS
AFTERNOON/EVENING. THERE IS STILL SOME DISAGREEMENT AS TO HOW
EXACTLY IT WILL PLAY OUT AND THERE IS A POSSIBILITY THAT THE
MORNING CLOUD COVER MAY HAVE BEEN ENOUGH TO DAMPEN SOME OF THE
THREAT FOR STRONGER TO SEVERE STORMS. BUT WITH THE DISTURBANCE
MOVING THROUGH AND BRINGING AMPLE MOISTURE THERE IS STILL
REASONABLY HIGH CONFIDENCE THAT AT LEAST A COUPLE OF THE STORMS
MAY BE STRONG TO SEVERE.
FOR SOUTHWEST MONTANA, THERE WILL BE A GREATER CONCERN FOR BOTH
WIND AND HAIL. FURTHER NORTH ABOVE A LINE ROUGHLY BETWEEN HELENA
AND WHITE SULPHUR SPRINGS, PRECIPITABLE WATER VALUES ARE CLOSE TO
THE DAILY CLIMATOLOGICAL MAX. WHILE SOME GUSTY WINDS AND SMALL
HAIL MIGHT BE PRESENT AT TIMES THE MAIN CONCERN WILL BE HEAVY
DOWNPOURS. FLASH FLOODING IS POSSIBLE BOTH FOR SLOW-MOVING STORMS
AND ANY TRAINING THUNDERSTORM SITUATION. POOR DRAINAGE AND URBAN
AREAS WILL BE AT THE HIGHEST RISK ALONG WITH BURN SCARS.
BECAUSE CONFIDENCE IS LACKING IN ANY ONE AREA OR ZONE RECEIVING
ENOUGH RAINFALL TO CAUSE WIDESPREAD FLASH FLOODING, FOR NOW, NO
FLOOD PRODUCTS WILL BE ISSUED. BUT THOSE LIVING IN CENTRAL AND
NORTH-CENTRAL MONTANA SHOULD HAVE A WAY TO RECEIVE WARNINGS,
ESPECIALLY DURING THE OVERNIGHT HOURS IN CASE THINGS END UP BEING
WORSE THAN WHAT IS CURRENTLY EXPECTED.
TUESDAY: RAIN IS EXPECTED TO CONTINUE ACROSS CENTRAL AND NORTH-
CENTRAL MONTANA THROUGH THE DAY ON TUESDAY WITH A CHANCE FOR SOME
AFTERNOON THUNDERSTORMS TO DEVELOP. HEAVY RAIN WILL ONCE AGAIN BE
A MAIN CONCERN FOR ANY SHOWER OR THUNDERSTORM THAT DEVELOPS WITH A
CHANCE FOR ISOLATED FLASH FLOODING EXTENDING THROUGH THE EVENING
HOURS ACROSS PORTIONS OF THE REGION, MAINLY EAST OF A LINE BETWEEN
GREAT FALLS AND CHESTER.
WEDNESDAY: DEWPOINT TEMPERATURES ON WEDNESDAY AFTERNOON ARE
SLIGHTLY LOWER COMPARED TO PREVIOUS MODEL RUNS. BUT WITH DEWPOINT
TEMPERATURES STILL EXPECTED TO REACH THE MID TO UPPER 50S,
AFTERNOON HIGHS ACROSS THE LOWER ELEVATIONS REACHING THE MID 80S
TO LOW 90S, AND BULK SHEAR IN THE 30 TO 50KT RANGE, THERE IS STILL
A GOOD CHANCE THAT AT LEAST A COUPLE STORMS TURN SEVERE. THE
DIFFERENCE THE FINAL POSITION OF THE TROUGH WILL MAKE IS WHETHER
OR NOT A COUPLE BECOME SEVERE, WHICH HAPPENS IF THE TROUGH STAYS
FURTHER NORTH, OR IF A FEW MORE BECOME SEVERE, WHICH WILL HAPPEN
IF THE TROUGH ENDS UP FURTHER SOUTH. THE MAIN THREATS WILL BE HAIL
AND WIND WITH SOME LOCALIZED HEAVY DOWNPOURS ALTHOUGH STORM
MOTION SHOULD BE FAST ENOUGH TO LESSEN THE FLASH FLOODING CONCERNS
COMPARED TO MONDAY AND TUESDAY.
FRIDAY AND BEYOND: AS THE RIDGE STARTS TO BUILD OVER THE REGION,
TEMPERATURES WILL CONTINUE TO WARM THROUGH THE WEEKEND WITH
SATURDAY EXPECTED TO BE THE WARMEST DAY. A GOOD PORTION OF NORTH-
CENTRAL MONTANA HAS A 20-30% CHANCE FOR HIGHS EXCEEDING 100
DEGREES BOTH SATURDAY AND SUNDAY. IN REALITY, THE OCCURRENCE OF
100+ HIGHS ARE LIKELY TO BE A BIT MORE SPORADIC WITH SOME OF THE
TYPICALLY HOTTER AREAS LIKE FORT BENTON AND THE UPPER MISSOURI
RIVER BREAKS PORTION OF NORTHERN EASTERN FERGUS COUNTY ARE THE
MOST LIKELY TO EXPERIENCE 100+ TEMPERATURES.
WHILE DRIER CONDITIONS ARE EXPECTED TO PERSIST AT LEAST THROUGH
EARLY NEXT WEEK THERE IS ALWAYS A NON-ZERO CHANCE FOR AN ISOLATED
SHOWER TO POP UP ALONG THE MOUNTAINOUS REGIONS. THESE SHOWERS WILL
GENERALLY BE CONFINED TO TERRAIN AREAS AND ARE UNLIKELY TO LAST
LONG. BUT THEY MAY POSE A RISK FOR THOSE RECREATING IN THE AREA,
ESPECIALLY IF LIGHTNING STARTS TO BECOME A FACTOR.
LONGER TERM GUIDANCE FROM CPC HAS SUGGESTED THAT THE CHANCE FOR
HOTTER TEMPERATURES MAY LINGER THROUGH MOST OF JULY. IF THIS
OCCURS THE MAIN CONCERN WILL BE COMPOUNDING HEAT STRESS FROM
MULTIPLE DAYS OF ABOVE NORMAL TEMPERATURES. THIS MAY CAUSE IMPACTS
FOR THOSE RECREATING OUTDOORS AND THOSE WITHOUT AIR CONDITIONING.
-THOR
AVIATION
07/06Z TAF PERIOD
INITIAL CONCERN WILL BE FOR AREAS OF SHOWERS AND THUNDERSTORMS
PROGRESSING NORTHWARD INTO NORTH-CENTRAL MONTANA WHICH LOOK TO LAST
THROUGH MID-MORNING. SOME MVFR CEILINGS LOOK TO ACCOMPANY THIS RAIN,
THOUGH THERE IS UNCERTAINTY IN ITS DURATION AND EXTENT. ANOTHER
ROUND OF SCATTERED SHOWERS AND THUNDERSTORMS THEN LOOKS TO DEVELOP
TUESDAY AFTERNOON IN MANY AREAS. -AM
PRELIMINARY POINT TEMPS/POPS
GTF 55 81 55 91 / 60 40 0 20
CTB 54 79 53 86 / 60 30 10 10
HLN 56 84 56 88 / 60 20 0 40
BZN 52 83 53 87 / 50 10 10 20
WYS 48 80 46 81 / 50 20 10 10
DLN 50 82 52 85 / 40 10 10 30
HVR 57 76 53 90 / 80 90 20 20
LWT 51 76 51 86 / 80 70 10 20
TFX WATCHES/WARNINGS/ADVISORIES
NONE.
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