669
FXUS65 KTFX 150511
AFDTFX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
1111 PM MDT THU MAY 14 2026
AVIATION SECTION UPDATED.
KEY MESSAGES
- IT WILL BE WINDY THIS AFTERNOON ACROSS THE PLAINS OF NORTH-
CENTRAL MONTANA.
- IT WILL COOL DOWN TO WELL-BELOW SEASONAL AVERAGE TEMPERATURES
BY SUNDAY.
- IT WILL BE MOSTLY DRY UNTIL SATURDAY AFTERNOON WITH LOWER-
ELEVATION AND MOUNTAIN SNOW POSSIBLE ON SUNDAY AND MONDAY.
UPDATE
/ISSUED 818 PM MDT THU MAY 14 2026/
THE UPPER LEVEL SYSTEM THAT BROUGHT VERY WINDY CONDITIONS TO THE
REGION TODAY CONTINUES TO TRACK EAST AND AWAY FROM THE AREA
ACROSS THE CANADIAN PRAIRIES. DECREASING MID-LEVEL WINDS AND
SURFACE PRESSURE GRADIENT ACROSS THE AREA HAS ALLOWED WINDS TO
GRADUALLY LOWER AND REMAINING PORTIONS OF THE HIGH WIND WARNING
WERE ENDED WITH ONLY AREAS ALONG THE IMMEDIATE EAST SLOPES OF THE
ROCKY MTN FRONT AND PORTIONS OF BLAINE COUNTY STILL LIKELY TO SEE
A FEW GUSTS IN EXCESS OF 40-50 MPH THROUGH THE REMAINDER OF THIS
EVENING. A WESTERLY UPPER LEVEL JET REMAINS POSITIONED ACROSS THE
PACIFIC NW AND NORTHERN ROCKIES WITH A WEAK DISTURBANCE PASSING
LATER TONIGHT THROUGH FRIDAY MORNING, BRINGING A PERIOD OF
INCREASED CLOUDS AND PERHAPS SOME VERY LIGHT RAIN/SNOW SHOWERS
ALONG NORTHERN PORTIONS OF THE CONTINENTAL DIVIDE BEFORE CLOUDS
DECREASE WITH ANOTHER BREEZY AFTERNOON ON FRIDAY. HOENISCH
DISCUSSION
/ISSUED 818 PM MDT THU MAY 14 2026/
- METEOROLOGICAL OVERVIEW:
THIS AFTERNOON THERE IS AN UPPER-LEVEL TROUGH OVER NORTH-CENTRAL,
CENTRAL, AND SOUTHWESTERN MONTANA. THIS AFTERNOON THERE REMAINS A
STRONG PRESSURE GRADIENT. THIS COMBINED WITH STRONG LOW AND MID-
LEVEL WINDS WILL BRING WINDY CONDITIONS TO NORTH-CENTRAL MONTANA.
THIS AFTERNOON ACROSS THE PLAINS OF NORTH-CENTRAL MONTANA THE
STRONG WINDS ARE CAUSING BLOWING DUST TO REDUCE VISIBILITY. THIS
AFTERNOON THERE WILL BE SNOW SHOWERS ALONG THE ROCKY MOUNTAIN
FRONT. THIS AFTERNOON TEMPERATURES WILL BE AROUND SEASONAL
AVERAGES. ON FRIDAY ZONAL FLOW IS OVER NORTH-CENTRAL, CENTRAL, AND
SOUTHWESTERN MONTANA. THIS WILL ALLOW IT TO BE MOSTLY DRY WITH
ABOUT SEASONAL AVERAGES FOR TEMPERATURES.
ON SATURDAY AN UPPER-LEVEL TROUGH ASSOCIATED WITH A SURFACE COLD
FRONT BEGINS TO MOVE OVER NORTH-CENTRAL, CENTRAL, AND SOUTHWESTERN
MONTANA. THIS WILL BRING PRECIPITATION AND COOLER TEMPERATURES TO
THE AREA ON SATURDAY. ON SUNDAY THE UPPER-LEVEL TROUGH REMAINS OVER
NORTH-CENTRAL, CENTRAL, AND SOUTHWESTERN MONTANA. THIS WILL BRING
WELL-BELOW SEASONAL AVERAGES FOR TEMPERATURES ON SUNDAY. ON SUNDAY
THERE WILL BE WIDESPREAD PRECIPITATION ACROSS THE AREA. ACROSS
MOUNTAIN LOCATIONS THIS WILL BE PRIMARILY SNOW. AT LOWER-ELEVATIONS
THIS WILL BE A RAIN/SNOW MIX. SUNDAY AFTERNOON THERE IS ENOUGH
INSTABILITY AROUND THAT THERE IS THE POTENTIAL FOR A FEW RUMBLES OF
THUNDER AS WELL. ON MONDAY THE UPPER-LEVEL TROUGH REMAINS OVER NORTH-
CENTRAL, CENTRAL, AND SOUTHWESTERN MONTANA. AS A RESULT
PRECIPITATION AND COLD TEMPERATURES (WELL-BELOW) SEASONAL AVERAGES
WILL LINGER ACROSS THE AREA. ON TUESDAY AND WEDNESDAY AN UPPER-LEVEL
RIDGE BUILDS IN OVER NORTH-CENTRAL, CENTRAL, AND SOUTHWESTERN
MONTANA. THIS WILL ALLOW TEMPERATURES TO GRADUALLY WARM UP WITH
MOSTLY DRY WEATHER. -IG
- FORECAST CONFIDENCE & SCENARIOS:
ON SATURDAY THERE IS A 10 - 20% CHANCE FOR THUNDER ACROSS
SOUTHWESTERN MONTANA. ON SUNDAY THERE IS A 15 - 25% CHANCE FOR
THUNDER ACROSS MOST OF NORTH-CENTRAL, CENTRAL, AND SOUTHWESTERN
MONTANA. SUNDAY THROUGH MONDAY THERE IS A 10 - 50% CHANCE FOR
GREATER THAN A TENTH OF AN INCH OF SNOW ACROSS THE LOWER-ELEVATIONS
OF NORTH-CENTRAL, CENTRAL, AND SOUTHWESTERN MONTANA SOUTH OF THE
MONTANA 200 CORRIDOR. ACROSS THE MOUNTAINS OF NORTH-CENTRAL,
CENTRAL, AND SOUTHWESTERN MONTANA THERE IS A 50 - 80% CHANCE FOR 4
INCHES OF SNOW OR GREATER. ONE AREA OF UNCERTAINTY WITH THIS
SNOWFALL IS WHEN IT FALLS WILL HAVE DRASTIC DIFFERENCES ON IMPACTS.
IF SNOW FALLS DURING DAYLIGHT HOURS THERE WILL BE MINIMAL IMPACTS.
HOWEVER IF SNOWFALL FALLS OVER NIGHT THIS HAS THE POTENTIAL TO LEAD
TO SOME IMPACTS. ANOTHER AREA OF UNCERTAINTY WITH THIS SYSTEMS
PRECIPITATION TYPES IS WHEN THE COLD AIR MOVES IN AND TRANSITIONS
PRECIPITATION AT THE LOWER-EELVATIONS FROM RAIN TO SNOW.
ON SUNDAY ACROSS MOST OF THE LOWER-ELEVATIONS OF NORTH-CENTRAL,
CENTRAL, AND SOUTHWESTERN MONTANA THERE IS A 20 - 50% CHANCE FOR
HIGH TEMPERATURES OF 45 DEGREES OR COLDER. MONDAY MORNING THERE IS
A 30 - 50% CHANCE FOR LOW TEMPERATURES OF 28 DEGREES OR COLDER
ACROSS THE LOWER-ELEVATIONS OF NORTH-CENTRAL, CENTRAL, AND
SOUTHWESTERN MONTANA. ON SUNDAY MORNING ACROSS THE LOWER-
ELEVATIONS OF SOUTHWESTERN MONTANA THERE IS GREATER THAN A 40%
CHANCE FOR LOW TEMPERATURES OF 28 DEGREES OR COLDER. -IG
AVIATION
15/06Z TAF PERIOD
VFR CONDITIONS WILL PREVAIL THROUGHOUT THE 1506/1606 TAF PERIOD
DESPITE PERIODS OF MID- TO UPPER LEVEL CLOUDINESS, WITH MOUNTAIN
(RIDGETOP) OBSCURATION BEING LIMITED TO BETWEEN 10-20Z FRIDAY.
OTHERWISE THE BIGGEST IMPACT TO TERMINALS WILL BE CONTINUED STRONG
AND GUSTY SURFACE WINDS, MOST NOTABLY AT THE KCTB TERMINAL WERE
FREQUENT WIND GUSTS OF BETWEEN 35-45KTS WILL BE COMMON THROUGHOUT
THE NEXT 24 HOURS, WITH GUSTS UP TO 35 KTS ACROSS MOST OF THE
REMAINING TERMINALS BEYOND 13Z FRIDAY. - MOLDAN
PRELIMINARY POINT TEMPS/POPS
GTF 42 62 40 58 / 0 0 10 30
CTB 37 57 34 54 / 0 0 10 10
HLN 39 63 38 56 / 0 0 10 60
BZN 36 65 35 60 / 0 0 10 40
WYS 31 63 30 57 / 0 0 0 10
DLN 36 65 37 60 / 0 0 10 30
HVR 40 65 37 63 / 0 10 0 10
LWT 38 61 36 59 / 0 0 10 40
TFX WATCHES/WARNINGS/ADVISORIES
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