textproduct: Great Falls

KEY MESSAGES

- Gusty winds and thunderstorms this evening.

- Cooler on Wednesday, with a few isolated showers.

- Seasonable temperatures starting Thursday and continuing into early next week.

DISCUSSION

/Issued 206 PM MDT Tue Jun 16 2026/

- Meteorological Overview: A northwesterly flow aloft will reside over Montana for the next few days. As a result, a fairly strong upper level disturbance will move southeastward through the CWA this evening, with North Central MT the most impacted. Expect showers/thunderstorms to accompany this disturbance, with some storms possible severe early this evening, mainly east of a line from Cut Bank, to Great Falls to Lewistown. Otherwise, strong surface wind gusts over North Central MT will continue into the late evening hours before diminishing.

On Wednesday and Thu, afternoon temperatures will be a bit cooler, with the northwesterly flow still causing a bit of instability over the CWA. Thus there is a small chance for an isolated shower, mostly over the norther portions of the CWA both days.

Friday into early next week...An upper level ridge will try to build over the Pacific Northwest Friday into the weekend. This will result in generally a northwesterly flow aloft over MT through the weekend. Precipitation chances are most likely on Sunday, as an upper level disturbance moves through the area. For early next week, the upper level ridge to our west will flatten a bit as it moves east. This will result in less of a chance of precipitation, but generally keep temperatures near seasonal normals.

- Forecast Confidence & Scenarios: The main concern this evening is the potential for severe storms over the northeastern portions of the CWA. Overall strong wind gusts look to the main weather concern. I am thinking the best time frame for the stronger storms to occur is from about 6 PM until about 11 PM. Overall rainfall amounts tonight will be on the lighter side, with most areas receiving less than 0.10 inches. However, a few locations might receive around a quarter of an inch from heavier thunderstorms. Brusda

AVIATION

17/00Z TAF Period

The gusty westerly winds will have decreased over much of the region by 05-07Z 6/17. Showers and thunderstorms will affect much of North Central MT this evening, as a cold front moves southward from Canada. Some of these showers/thunderstorms could mix down higher winds aloft, resulting in isolated gusts greater than 45 kts. Most showers end by 12z Wed, with just a few lingering showers during the day on Wed. Brusda/Dzomba

PRELIMINARY POINT TEMPS/POPS

GTF 50 69 46 73 / 40 20 30 10 CTB 45 66 43 68 / 70 30 30 20 HLN 52 75 47 79 / 0 10 10 0 BZN 52 75 43 78 / 0 0 0 0 WYS 40 73 34 76 / 0 0 0 0 DLN 48 76 42 80 / 0 0 0 0 HVR 47 68 43 71 / 80 30 20 30 LWT 45 65 40 68 / 60 20 20 40

TFX WATCHES/WARNINGS/ADVISORIES

High Wind Warning until midnight MDT tonight for Big Belt, Bridger and Castle Mountains-East Glacier Park Region-Eastern Glacier, Western Toole, and Central Pondera-Judith Basin County and Judith Gap-Northern High Plains-Southern High Plains- Southern Rocky Mountain Front-Upper Blackfoot and MacDonald Pass.