607
FXUS65 KTFX 262026
AFDTFX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
226 PM MDT SUN APR 26 2026
KEY MESSAGES
- MUCH COOLER THAN AVERAGE TEMPERATURES AND UNSETTLED CONDITIONS
PERSIST THOUGH MONDAY WITH NEAR RECORD LOW TEMPERATURES IN SOME
LOCATIONS MONDAY MORNING.
- PERIODS OF LIGHT SNOW ACROSS SOUTHWEST MT TONIGHT WILL BRING SOME
MINOR ACCUMULATION, MAINLY TO MOUNTAIN PASSES.
- A GRADUAL WARMING TREND BEGINS TUESDAY WITH TEMPERATURES
RETURNING TO AROUND SEASONAL AVERAGES FOR MID TO LATE THIS
WEEK.
DISCUSSION
- METEOROLOGICAL OVERVIEW:
A SPRAWLING CLOSED UPPER LEVEL LOW REMAINS CENTERED ACROSS SK WITH
TROUGHING EXTENDING TO ITS SOUTHWEST ACROSS THE WESTERN US. THE LOW
WILL SLOWLY LIFT OUT TO THE EAST/NORTHEAST EARLY THIS WEEK, BUT
TROUGHING WILL LINGER ACROSS THE NORTHERN ROCKIES AND MT THROUGH
THE THE FIRST HALF OF THE WORK WEEK.
MULTIPLE EMBEDDED SHORTWAVE DISTURBANCES CONTINUE TO ROTATE THROUGH
THE TROUGH, WITH ONE TRACKING EAST ACROSS CENTRAL/SOUTHERN MT TODAY
BEFORE ANOTHER DROPS SOUTH FROM BC AND TRACKS ACROSS SOUTHWEST MT
LATER TONIGHT THROUGH MONDAY MORNING. AREAS OF ENHANCED DAYTIME SNOW
SHOWER ACTIVITY AND OVERNIGHT LIGHT SNOW ACCOMPANY THESE
DISTURBANCES THROUGH MONDAY WHILE THE OVERALL COLD AIR ALOFT AND
UNSTABLE/CYCLONIC NORTHWESTERLY FLOW WILL CONTINUE TO SUPPORT MORE
SCATTERED SNOW SHOWERS/FLURRIES OUTSIDE OF THESE AREAS THROUGH
MONDAY AFTERNOON.
TEMPERATURES REMAIN WELL BELOW AVERAGE THROUGH MONDAY WITH A WARMING
TREND BEGINNING TUESDAY AND CONTINUING THROUGH FRIDAY. FLOW ALOFT
REMAINS CYCLONIC AND NORTHWESTERLY THROUGH WEDNESDAY BEHIND THE
DEPARTING UPPER LEVEL SYSTEM WITH ENOUGH MINOR DISTURBANCES,
LINGERING MOISTURE AND AFTERNOON INSTABILITY TO SUPPORT DIURNAL
SHOWER DEVELOPMENT AND EVEN THE POTENTIAL FOR A FEW ISOLATED
THUNDERSTORMS.
THE WARMEST/DRIEST DAYS OF THE UPCOMING WEEK WILL BE THURSDAY AND
FRIDAY AS RIDGING BRIEFLY DEVELOPS OVER THE WESTERN US. BY NEXT
WEEKEND, RIDGING SHIFTS WEST AND BUILDS OFFSHORE OF THE PACIFIC
NW WITH QUITE A BIT OF UNCERTAINTY IN THE DOWNSTREAM INTERACTION
OF TROUGHING REDEVELOPING ACROSS CANADA AND A SOUTHERN STREAM
SYSTEM LOCATED NEAR CA. HOENISCH
- FORECAST CONFIDENCE & SCENARIOS:
TONIGHT COULD BE THE COLDEST OF THE THIS STRETCH OF COOLER
WEATHER, PARTICULARLY ACROSS PARTS OF NORTH-CENTRAL MT, WHERE SOME
PARTIAL CLEARING IS EXPECTED. OVERNIGHT LOW TEMPERATURES MAY
REACH DAILY RECORDS AT SOME NORTH-CENTRAL MT LOCATIONS WITH THE
RISK FOR MINIMUM TEMPERATURES AT OR BELOW 15F RANGING FROM 25-35%
AT GREAT FALLS AND LEWISTOWN TO AROUND 50% NEAR HAVRE AND 90% OR
HIGHER ACROSS MOST OF GLACIER AND LIBERTY COUNTIES. WHILE MOST
AREAS HAVE SEEN SUB-FREEZING TEMPERATURES THE LAST FEW NIGHT, THE
ADDITIONAL DROP TONIGHT COULD HAVE A GREATER IMPACT ON
TENDER/EMERGING VEGETATION.
ADDITIONAL SNOW ACCUMULATION THROUGH MONDAY WILL BE MINOR (LESS
THAN 1") ACROSS MOST LOWER ELEVATION AREAS. THE DISTURBANCE MOVING
THROUGH SW MT TONIGHT THROUGH TOMORROW WILL BRING A PERIOD OF
STEADIER SNOW TO AREAS ALONG THE IDAHO BORDER AND ACROSS THE
MOUNTAINS AS FAR NORTH AS THE ELKHORN/BOULDER AND LITTLE/BIG BELT
RANGES WITH UP TO 3" AT THE HIGHEST ELEVATIONS BUT ACCUMULATIONS
CLOSER TO AROUND 1" AT PASS LEVELS. THE MAIN IMPACT FROM THIS
COULD BE SOME LOCALIZED SLUSHY/SLICK ROADS OVER MOUNTAIN PASSES
FOR THE MONDAY MORNING COMMUTE. HOENISCH
AVIATION
26/18Z TAF PERIOD
SHORTWAVE ENERGY AND A MOIST LOW LEVEL EASTERLY FLOW WILL
MAINTAIN LOW STRATUS, MOUNTAIN OBSCURATION AND PERIODS OF LIGHT
SNOW OVER NORTH- CENTRAL AND SOUTHWEST MT FOR MUCH OF THE PERIOD.
THE FOCUS OF THE SNOW WILL SHIFT INTO SOUTHWEST MT AFTER 26/21Z,
BUT MVFR/IFR STRATUS WILL LINGER FOR MOST TERMINALS THROUGH MONDAY
MORNING. - RCG
TONIGHT COULD BE THE COLDEST OF THE THIS STRETCH OF COOLER WEATHER,
PARTICULARLY ACROSS PARTS OF NORTH-CENTRAL MT, WHERE SOME PARTIAL
CLEARING IS EXPECTED. OVERNIGHT LOW TEMPERATURES MAY REACH DAILY
RECORDS AT SOME NORTH-CENTRAL MT LOCATIONS WITH THE RISK FOR MINIMUM
TEMPERATURES AT BELOW 15F RANGING FROM 25-35% AT GREAT FALLS AND
LEWISTOWN TO AROUND 50% NEAR HAVRE AND 90% OR HIGHER ACROSS MOST OF
GLACIER AND LIBERTY COUNTIES. WHILE MOST AREAS HAVE SEEN SUB-
FREEZING TEMPERATURES THE LAST FEW NIGHT, THE ADDITIONAL DROP
TONIGHT COULD HAVE GREATER IMPACT IN TENDER/EMERGING VEGETATION.
ADDITIONAL SNOW ACCUMULATION THROUGH MONDAY WILL BE MINOR LESS THAN
1") ACROSS MOST LOWER ELEVATION AREAS. THE DISTURBANCE MOVING
THROUGH SW MT TONIGHT THROUGH TOMORROW WILL BRING A PERIOD OF
STEADIER SNOW TO AREAS ALONG THE IDAHO BORDER AND ACROSS THE
MOUNTAINS AS FAR NORTH AS THE ELKHORN/BOULDER, LITTLE AND BIG BELT
RANGES WITH UP TO 3" AT THE HIGHEST ELEVATIONS BUT ACCUMULATIONS
CLOSER TO AROUND 1" AT PASS LEVELS. THE MAIN IMPACT FROM THIS COULD
BE SOME LOCALIZED SLUSHY/SLICK ROADS OVER MOUNTAIN PASSES FOR THE
MONDAY MORNING COMMUTE. HOENISCH
PRELIMINARY POINT TEMPS/POPS
GTF 19 49 27 58 / 30 20 10 30
CTB 10 46 23 56 / 10 10 0 10
HLN 24 50 28 57 / 30 40 10 40
BZN 24 47 23 55 / 40 50 20 30
WYS 20 44 18 47 / 60 70 40 40
DLN 26 48 26 54 / 50 60 20 10
HVR 17 48 24 59 / 0 10 0 0
LWT 19 42 23 53 / 50 40 10 40
TFX WATCHES/WARNINGS/ADVISORIES
NONE.
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