textproduct: Great Falls

KEY MESSAGES

- Impactful winter weather continues across Central and Southwest Montana through Friday morning with impacts expected for the Friday morning commute.

- Another round of gusty winds will develop across North-Central Montana Friday afternoon.

- Impactful winter weather conditions are expected along the Hi- Line starting Friday morning and lasting through Saturday morning with the potential for localized blowing/drifting snow Friday afternoon.

- Overall cooler and unsettled conditions persist this weekend before gradually warming early next week.

DISCUSSION

/Issued 402 PM MDT Thu Apr 23 2026/

- Meteorological Overview:

Another shortwave will continue to make its way south bringing widespread chances for impactful snow across central and southwest Montana through late Friday morning. Impacts below pass level are generally expected to remain minor. The highest snowfall and impacts are expected along the Madison and Gallatin ranges which will remain under a Winter Storm Warning through the period.

Friday morning through Saturday morning, a combination of northwest flow and wrap around moisture will allow for the development of snow showers and another round of gusty conditions along the Hi-Line. Depending on how the timing of the heaviest snow and strongest winds play out, there is a chance for some brief periods of blowing/drifting snow across portions of the US-2 corridor which may lead to reduced visibility at times.

Heading through the weekend, the upper level low continues to slowly migrate towards the northeast out of central Saskatchewan towards northern Manitoba. In the meantime, our region will remain under a west to northwesterly flow which will allow for unsettled weather to continue, primarily in the form of daily chances for mountain snow through at least Monday. Temperatures will remain cool through the weekend before a warming trend starts back up by the early to middle of next week as the trough continues to move further east and upper level ridging starts to build back up in its place.

- Forecast Confidence & Scenarios:

Southwest/Central Montana Snow:

For the most part the going forecast from earlier today remains on track in terms of the expected impacts and snowfall amounts.

One wild card through tomorrow morning will be the Little Belts. The current Winter Storm Warning ends at 6 PM tonight and, as of now, the snowfall that is forecasted between 6 PM tonight and noon tomorrow is not high enough to warrant an extension of the warning. So for now a Winter Weather Advisory was added on to account for snow that is expected to be impactful but not severe. There is a chance that the Little Belts could over-perform which might warrant an upgrade at a later time but even this afternoon there is some uncertainty as to whether that will happen.

Otherwise, there was no need to add any additional zones to the advisories across southwest and central Montana.

Hi-Line Snow:

There is high enough confidence in the potential for snow along the Hi-Line to warrant Winter Weather Advisories. The two wild cards will be the Sweetgrass Hills and the Bears Paw. The Sweetgrass Hills could potentially get close to warning criteria but because higher snowfall amounts are not currently expected to expand over a wider area past the hills, the decision was made to keep it as an advisory for now.

For the Bears Paw, given the setup with cold northwesterly flow, it is much more likely that areas along the higher elevations of the mountains over-perform and receive much higher amounts compared to the surrounding portions of the Hi-Line. For this reason, a Winter Storm Warning was issued for the Bears Paw with the most impactful snowfall amounts expected above 4000 feet. This could make travel difficult along area roads including Montana 234.

One concern particular to the Hi-Line tomorrow will be strong winds through Friday afternoon/evening. Confidence is too low to issue another High Wind Warning for the region but with gusts up to 50 mph possible, there is a concern that if the heavier snowfall rates overlap with the stronger wind gusts there could be periods of reduced visibility along area roads. Motorists should be prepared for sudden reductions in visibility along area roads. -thor

AVIATION

24/00Z TAF Period

VFR conditoons will prevail at the KGTF terminal during this TAF Period. At the KBZN, KEKS, KHLN, and KWYS terminal there will be snow during the majority of this TAF Period. At the KGTF, KLWT and KCTB terminals there will be isoalted snow showers around during portions of this TAF Period. After 24/15Z there will be snow and gusty winds at the KHVR temrinal which will reduce visbility to at least MFR-levels with a low chance for the snow to reduce visbility to as low as 1 mile. There will be instances of mountain obscuration across much of North-central, Central, and Southwestern Montana during this TAF Period. -IG

PRELIMINARY POINT TEMPS/POPS

GTF 25 38 24 42 / 40 70 30 20 CTB 22 35 19 38 / 30 60 20 20 HLN 23 40 21 45 / 70 50 20 20 BZN 21 40 16 46 / 70 60 10 20 WYS 17 36 11 43 / 70 70 10 20 DLN 22 40 18 46 / 70 50 10 10 HVR 24 36 21 41 / 30 70 40 20 LWT 21 34 18 40 / 10 60 20 20

TFX WATCHES/WARNINGS/ADVISORIES

Winter Weather Advisory until 6 PM MDT this evening for East Glacier Park Region.

Winter Weather Advisory from 3 AM Friday to noon MDT Saturday for Eastern Toole and Liberty-Hill County-Northern Blaine County.

High Wind Warning until 6 PM MDT this evening for Bears Paw Mountains and Southern Blaine-Fergus County below 4500ft- Northern Blaine County.

Winter Storm Warning from 3 AM Friday to noon MDT Saturday for Bears Paw Mountains and Southern Blaine.

Winter Weather Advisory until noon MDT Friday for Big Belt, Bridger and Castle Mountains-Elkhorn and Boulder Mountains-Gates of the Mountains-Helena Valley-Northwest Beaverhead County-Ruby Mountains and Southern Beaverhead Mountains-Southern Rocky Mountain Front-Upper Blackfoot and MacDonald Pass.

Winter Storm Warning until 6 PM MDT this evening for Little Belt and Highwood Mountains.

Winter Weather Advisory until noon MDT Friday for Beaverhead and Western Madison below 6000ft-Canyon Ferry Area-Gallatin Valley- Little Belt and Highwood Mountains-Madison River Valley-Meagher County Valleys-Missouri Headwaters.

Winter Storm Warning until noon MDT Friday for Gallatin and Madison County Mountains and Centennial Mountains.