083
FXUS65 KTFX 280533
AFDTFX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
1133 PM MDT MON APR 27 2026
AVIATION SECTION UPDATED.
KEY MESSAGES
- ONE MORE NIGHT OF WIDESPREAD SUB-FREEZING TEMPERATURES
TONIGHT.
- TEMPERATURES GRADUALLY WARM THROUGH THE REST OF THE WORK WEEK
WITH WARMEST READINGS LIKELY THURSDAY AND FRIDAY.
- MAINLY AFTERNOON AND EARLY EVENING SHOWERS EACH DAY THROUGH
WEDNESDAY WITH AN ISOLATED THUNDERSTORM POSSIBLE.
DISCUSSION
- METEOROLOGICAL OVERVIEW:
THE UPPER LEVEL TROUGH EXTENDING FROM CANADA SOUTHWEST ACROSS THE
WESTERN US WILL GRADUALLY WEAKEN WHILE SHIFTING EAST OVER THE
NEXT SEVERAL DAYS. A CYCLONIC NORTHWESTERLY FLOW ALOFT LINGERS
ACROSS THE NORTHERN ROCKIES AND MT THROUGH WEDNESDAY WITH WEAK
EMBEDDED DISTURBANCES AND LIMITED MOISTURE COMBINING WITH DAYTIME
HEATING TO SUPPORT THE DIURNAL DEVELOPMENT OF SCATTERED SHOWERS
AND PERHAPS AN ISOLATED THUNDERSTORM OR TWO EACH AFTERNOON THROUGH
WEDNESDAY.
ONE MORE NIGHT OF WIDESPREAD SUB-FREEZING TEMPERATURES IS EXPECTED
TONIGHT WITH A RETURN TO SEASONAL TEMPERATURES BEGINNING TUESDAY.
UPPER LEVEL RIDGING BUILDS ACROSS THE NW US THURSDAY AND FRIDAY FOR
MAINLY DRY CONDITIONS AREA-WIDE WITH AFTERNOON TEMPERATURES WARMING
ABOVE SEASONAL AVERAGES AND LIKELY TO PEAK ON FRIDAY WITH AFTERNOON
TEMPERATURES IN THE UPPER 60S TO LOW 70S. HOENISCH
- FORECAST CONFIDENCE & SCENARIOS:
THROUGH THIS EVENING, WIDELY SCATTERED SHOWERS WILL PRIMARILY BE
FOCUSED ACROSS SOUTHWEST MT AND NORTH ALONG THE CONTINENTAL
DIVIDE. ON TUESDAY AND WEDNESDAY, THE COVERAGE OF SHOWERS AND
POSSIBLE THUNDERSTORMS WILL BE A BIT BROADER ACROSS WESTERN
PORTIONS OF NORTH-CENTRAL MT AS WELL AS MUCH OF CENTRAL AND
SOUTHWEST MT. THROUGH THIS EVENING, PRECIPITATION ASSOCIATED WITH
ANY SHOWERS WILL PRIMARILY BE SNOW. TUESDAY AND WEDNESDAY, SNOW
LEVELS RISE TO AROUND 6000 FT OR HIGHER, HOWEVER ENOUGH COLD AIR
ALOFT REMAINS IN PLACE TO SUPPORT GRAUPEL OR VERY SMALL HAIL DOWN
TO THE SURFACE WITH MORE INTENSE SHOWER ACTIVITY.
LONGER RANGE MODEL ENSEMBLES ARE IN GENERAL AGREEMENT ON THE BROADER
PATTERN EVOLVING THIS WEEKEND AS UPPER RIDGING AMPLIFIES OFFSHORE OF
BC WITH PACIFIC ENERGY DIVING SOUTH ALONG OR OFFSHORE OF THE US WEST
COAST. MEANWHILE, ENERGY COMING OVER THE EASTERN PACIFIC RIDGE LOOKS
TO DIVE SOUTH THROUGH CENTRAL CANADA, CARVING OUT A BROADER TROUGH
THAT DEEPENS INTO THE N-CENTRAL US BY EARLY NEXT WEEK. UNCERTAINTY
EXISTS IN THE TIMING OF ENERGY MOVING SOUTH OUT OF CANADA BY LATER
THIS WEEKEND AND THE EXTEND OF ANY MOISTURE MOVING OUT OF THE SW US
LOW. IN ANY CASE, SOME COOLING IS LIKELY TO BEGIN THIS WEEKEND WITH
LOW CONFIDENCE IN THE AMOUNT OF COOLING AND OCCURRENCE OF
PRECIPITATION. HOENISCH
AVIATION
28/06Z TAF PERIOD
AN UNSTABLE NORTHWESTERLY FLOW ALOFT WILL RESIDE OVER THE CWA
THROUGH THE PERIOD. WITH COLD AIR ALOFT, THERE WILL BE A CHANCE
FOR SCATTERED RAIN SHOWERS ACROSS THE CWA. THE MOST LIKELY TIME AT
THE TERMINALS WILL BE LATE MORNING THROUGH THE AFTERNOON. SINCE
MOST OF THE SHOWERS WILL BE BRIEF, FOR NOW, I CONFINED POPS TO
JUST THE AFTERNOON HOURS AT THE TERMINAL SITES. BUT KNOW THAT
SHOWERS WILL BE POSSIBLE ACROSS THE CWA THROUGH THE PERIOD. A
LIGHTNING STRIKE IS ALSO POSSIBLE, BUT WITH THE PROBABILITY OF
THUNDER ONLY AROUND 15 PERCENT, I KEPT IT OUT OF THE TERMINAL
SITES AS WELL. MOUNTAINS/PASSES WILL BE OBSCURED AT TIMES ACROSS
THE CWA BY SHOWERS/CLOUDS. BRUSDA
PRELIMINARY POINT TEMPS/POPS
GTF 27 56 33 58 / 10 40 20 30
CTB 23 54 29 56 / 20 20 40 20
HLN 29 57 33 58 / 30 40 30 50
BZN 24 54 30 56 / 10 50 30 50
WYS 17 46 22 49 / 30 50 30 50
DLN 25 54 31 56 / 10 50 10 30
HVR 25 58 29 59 / 10 30 10 10
LWT 24 52 28 53 / 10 50 30 40
TFX WATCHES/WARNINGS/ADVISORIES
NONE.
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