textproduct: Great Falls

KEY MESSAGES

- Strong winds will continue along the Rocky Mountain Front through the weekend with the strongest winds expected on Sunday.

- Periods of strong winds are possible along the Highway 200 corridor on Saturday with more widespread and stronger winds expected across the region on Sunday.

- Mountain snow and lower elevation rain/snow mix is possible through the weekend with periods of unsettled weather expected to continue through the next week.

DISCUSSION

/Issued 309 PM MST Fri Mar 6 2026/

- Meteorological Overview:

Through today and tomorrow the upper-level ridge will start to break down allowing for a shift towards northwest flow and breezy conditions heading into Saturday. By Sunday, strong upper-level flow will set up across Montana with steep lapse rates expected to help bring some of the more damaging winds to the surface across the region. Gusts up to 75 mph will be possible along the Northern Plains with isolated gusts up to 100 mph possible along the Rocky Mountain Front.

More zonal flow returns Sunday evening into Monday as winds start to calm down with multiple rounds of shortwaves expected to move across the region through next week bringing daily chances for precipitation and breezy conditions.

- Forecast Confidence & Scenarios:

Snow:

Overwhelming, the majority of the snow will be found in the mountains over the weekend with the highest amounts along the Rocky Mountain Front.

One of the wild cards is the Hi-Line right along the Canadian border. There is currently around a 60-80% chance of receiving an inch or more Sunday night through Monday morning with a 20-40% chance of some isolated cases of 2 inches or more. For the time being, there is not enough confidence in snowfall amounts of impacts to warrant an advisory along the Hi-Line but this will be watched with future updates.

Otherwise, snow primarily remains confined to the mountains Tuesday and Wednesday with a less than 20% chance for a stray rain/snow shower at nearby lower elevation locations.

Saturday Wind:

Along the Rocky Mountain Front, strong winds will start to pick up Saturday morning and continue through late Sunday evening.

One of the main concerns is that a lot of the upper-level support has diminished compared to previous model runs with 700 mb. Upper level winds are sitting in the 30-40kt range now which is less than ideal for a confident high wind event. Probability-wise, there is still a greater than 80% chance for maximum wind gusts exceeding 50 mph along the Highway 200 corridor between Great Falls and Lewistown but the probabilities drop off fast with higher wind gusts. Outside of the Rocky Mountain Front, there is only a 30% chance of gusts exceeding 60 mph right around the Geyser area. As a result, there is diminishing confidence in whether this portion of the high wind event will pan out. But there is still enough confidence in higher gusts that it is worth holding onto the watch just a little longer to make sure this trend is confirmed in the next model runs. But the most likely scenario as of now is that gusts 40-50 mph are expected in this area with an isolated gust up to 60 mph, particularly in the wind- prone areas of Judith Basin county towards Judith Gap.

Sunday Wind:

Confidence continues to increase for the likelihood of very strong winds across central and north-central Montana. Across the Northern Plains, there is a 60-80% chance for gusts over 60 mph and 30-50% chance for gusts over 70 mph. Along the Rocky Mountain Front, there is a 60-80% chance for gusts over 80 mph and 20-30% chance for gusts over 100 mph.

There are some lingering uncertainties with regards to how far south the high winds go. The I-90 corridor still holds a 50-60% chance for gusts greater than 60 mph but it pales in comparison to the higher confidence shown further north. As a result, the watch for Sunday was left alone and future updates will address if additional zones need to be added or removed to the eventual warning.

Windy Next Week:

Extended model guidance continues to suggest the potential for breezy conditions continuing through the next week. While most locations will likely stay in the 30-40 mph threshold there are elevated probabilities (above 50%) for gusts above 50 mph on Wednesday and Thursday. Any finer details are far from resolved but it is worth keeping an eye on for future forecast updates. -thor

AVIATION

07/00Z TAF Period

VFR conditions will prevail during this TAF Period at all terminals. At the KEKS and KHLN terminals between 07/12Z and 07/20Z there is a 10 - 25% chance for rain and/or a rain/snow mix. At the KGTF, KHVR, and KLWT terminals it will be windy during much of this TAF period with several hours of wind gusts in excess of 30 kts towards the end of this TAF Period. At the KCTB terminal it will be very windy during this TAF Period with a few hours of wind gusts in excess of 50 kts at the end of this TAF Period. There will be mountain obscuration across Southwestern Montana between 07/11Z and 07/19Z. Between 07/03Z and 07/18Z there will be isolated instances of low- level wind shear and mountain wave turbulence across North-central and Central Montana. -IG

FIRE WEATHER

There will be elevated fire weather concerns for grassland areas this weekend. Particularly for areas that received little to no precipitation yesterday and today. Strong winds, gusting over 60 mph at times, combined with high temperatures in the upper 50s and 60s and minimum relative humidity values in the 20s and 30s may make it difficult to contain any existing or new fire starts. The worst conditions look to occur on Sunday when the winds will be strongest and most widespread. - RCG/IG

PRELIMINARY POINT TEMPS/POPS

GTF 33 58 47 59 / 0 10 0 10 CTB 33 54 43 53 / 0 10 0 40 HLN 30 54 40 60 / 10 20 10 10 BZN 22 53 33 61 / 0 20 0 0 WYS 12 35 26 43 / 0 40 30 30 DLN 24 50 33 56 / 10 10 0 0 HVR 30 63 41 59 / 0 0 0 30 LWT 27 55 39 59 / 0 0 0 10

TFX WATCHES/WARNINGS/ADVISORIES

High Wind Warning from 2 AM Saturday to midnight MST Sunday night for East Glacier Park Region-Eastern Glacier, Western Toole, and Central Pondera-Northern High Plains-Southern High Plains-Southern Rocky Mountain Front.

High Wind Watch from late Saturday night through Sunday evening for Bears Paw Mountains and Southern Blaine-Big Belt, Bridger and Castle Mountains-Canyon Ferry Area-Eastern Pondera and Eastern Teton-Eastern Toole and Liberty-Elkhorn and Boulder Mountains-Gallatin Valley-Gates of the Mountains-Helena Valley- Hill County-Little Belt and Highwood Mountains-Meagher County Valleys-Missouri Headwaters-Northern Blaine County-Snowy and Judith Mountains-Upper Blackfoot and MacDonald Pass-Western and Central Chouteau County.

High Wind Watch from Saturday morning through Sunday evening for Cascade County below 5000ft-Fergus County below 4500ft-Judith Basin County and Judith Gap.