textproduct: Great Falls

KEY MESSAGES

- A mix of rain and snow develops along the Continental Divide Tuesday.

- Windy day for most areas Wednesday.

- Cooler for Thursday but trending warmer and drier for Friday into the weekend.

DISCUSSION

/Issued 543 PM MDT Mon Mar 23 2026/

- Meteorological Overview:

Broad, low amplitude ridging is in place across the west to open up the week, which will allow for benign conditions to continue into early Tuesday. Better moisture aloft arrives during the day Tuesday ahead of a system off the Pacific NW and BC coastline. A mix of rain and snow develops along the Continental Divide (Mainly the Rocky Mountain Front) Tuesday into Tuesday night before having slightly better success making inroads east of the Continental Divide Wednesday.

The aforementioned system off the BC/Pacific NW coast ejects a wave with embedded stronger mid-level flow toward the Northern Rockies late Tuesday into Wednesday, which will further help to flatten the ridge. Gusty winds develop as a result, initially along the Rocky Mountain Front Tuesday afternoon, though strongest winds hold off til Wednesday. The combination of lower-end ridgetop stability, strength of winds in that stable layer, and lack of a robust pressure gradient eases concerns for the higher-end winds materializing along the Rocky Mountain Front into Wednesday. By late Wednesday morning daytime mixing takes over, which will have greater success translating the stronger winds aloft to the surface across the entire region.

A cool northwesterly flow aloft Thursday will result in snow showers across the region late Thursday morning through the early evening before upper level ridging begins building in across the west. Temperatures begin to trend warmer Friday, trending above 60 degrees in most if not all lower elevation areas for this weekend. Dry conditions are forecast Friday through the weekend.

Confidence in the pattern decreases toward early next week. There's roughly a 50-50 split between cluster members who continue the ridging and associated warmer/drier conditions, while the other 50% introduce some sort of troughing near the Pacific NW coast. -AM

- Forecast Confidence & Scenarios:

Wind Wednesday: Probabilistic guidance has not trended in either direction for the Wednesday timeframe, largely sitting around the 50% range for a 58 mph gust for areas where the High Wind Watch is in effect. Slightly higher probabilities exist for 58 mph around the Cut Bank area, though this is associated with daytime mixing Wednesday. Given this event is still 36-48 hours away and confidence is not overwhelming in most areas, no High Wind Warnings were introduced with this forecast update. -AM

AVIATION

24/06Z TAF Period.

Mid level clouds continue overnight. Rain/snow develops along the Continental Divide Tuesday morning. There's a slight chance for isolated showers to move off of the Continental Divide to the plains Tuesday afternoon and evening, but rain will be isolated and mostly virga. As a result there isn't much confidence in it impacting terminals. Breezy southwest/west winds pick up Tuesday afternoon and will continue through Tuesday evening. -Wilson

FIRE WEATHER

Given the combination of recent dry conditions, forecast gusty winds, relatively low relative humidities, and receptive fuels in the Bozeman to Helena corridor and adjacent areas, a Fire Weather Watch was introduced for the afternoon and early evening hours Wednesday for Fire Weather Zone 118. Any area that is below the snow line in this district will see increased fire weather concerns over this timeframe.

Additional concerns exist further north across North-central Montana Wednesday, though the combination of slightly cooler temperatures and slightly higher relative humidity over the plains and adjacent areas lowers confidence in widespread elevated to critical fire weather conditions. Trends will continue to be monitored. -AM

PRELIMINARY POINT TEMPS/POPS

GTF 40 64 49 61 / 10 10 20 10 CTB 33 55 41 52 / 0 20 30 10 HLN 37 66 45 63 / 0 10 30 30 BZN 37 68 46 72 / 0 10 20 10 WYS 30 56 37 61 / 10 10 10 10 DLN 39 66 45 67 / 0 0 10 0 HVR 32 59 41 61 / 0 10 30 0 LWT 36 63 45 64 / 0 10 30 20

TFX WATCHES/WARNINGS/ADVISORIES

High Wind Watch from late Tuesday night through Wednesday afternoon for Eastern Glacier, Western Toole, and Central Pondera-Eastern Toole and Liberty.

High Wind Watch from Wednesday morning through Wednesday evening for Beaverhead and Western Madison below 6000ft-Big Belt, Bridger and Castle Mountains-Gallatin Valley-Gallatin and Madison County Mountains and Centennial Mountains-Hill County- Madison River Valley-Missouri Headwaters-Northern Blaine County- Ruby Mountains and Southern Beaverhead Mountains.

Fire Weather Watch from Wednesday afternoon through Wednesday evening for Helena and Townsend Ranger Districts of the Helena National Forest.