textproduct: Great Falls

KEY MESSAGES

- Impactful heat expected through the weekend with little overnight relief in some areas.

- Daily chances for scattered thunderstorms across Southwest and Central Montana through the weekend.

- Elevated to critical fire weather concerns through the weekend.

DISCUSSION

/Issued 507 AM MDT Fri Jul 24 2026/

Upper-level ridging will continue across the Intermountain West keeping Montana hot for at least a while. High temperatures ranging from the upper 90s to mid 100s are expected across the lower elevations through Sunday with poor overnight temperature recovery expected for portions of North-Central Montana highlighted in the Extreme Heat Warning. Those recreating or spending an extended amount of time outdoors should prepare to take plenty of breaks, stay hydrated, and be on the lookout for any symptoms of heat-related illness.

Additionally there will be daily chances for isolated to scattered afternoon thunderstorms over the next few days. Thunderstorms on Friday and Saturday are expected to be on the drier side which means there will be a concern that cloud to ground lightning and gusty, erratic winds may further increase already present fire weather concerns.

While the worst of the heat is expected to be over after Sunday, it may be a while before a true cool down is expected as long- range models suggest the upper-level ridge could persist through at least the end of next week. Those who are most sensitive to the heat should be on the lookout for compounding heat stress, especially if they are without air conditioning or unable to find a cool location to recover. -thor

AVIATION

24/18Z TAF Period

VFR conditions prevail. Smoke/haze from regional wildfires will affect slantwise visibility upon ascent/descent at times across all terminals. Otherwise, isolated showers and thunderstorms are expected to develop during the afternoon hours along and south of Interstate 90 and persist into the late evening hours tonight. While confidence was too low to insert mention of these showers and storms the KBZN and KLWT terminals are the most at risk of seeing precipitation within the vicinity of the terminal.

FIRE WEATHER

A Red Flag Warning is in effect across portions of North-Central Montana on Friday and Saturday with widespread minimum RH values below 15%, frequent gusts up to 40 mph, and hot temperatures expected during this time period. Additionally, isolated thunderstorms may produce localized strong wind gusts and cloud to ground lightning. The concern will be that any fire that starts may be very difficult to contain. Folks should do everything possible to prevent a spark while traveling and/or recreating outdoors.

Marginal to elevated fire weather concerns may extend into Sunday and Monday as well, however confidence in critical conditions is too low at the moment to issue additional fire weather products at this time. -thor

PRELIMINARY POINT TEMPS/POPS

GTF 99 65 102 61 / 0 0 10 10 CTB 91 56 97 59 / 0 0 0 0 HLN 97 63 99 61 / 0 0 30 20 BZN 97 61 97 59 / 0 10 40 30 WYS 88 59 86 57 / 0 20 20 10 DLN 93 58 92 56 / 0 10 40 30 HVR 101 62 106 64 / 0 0 0 10 LWT 94 62 98 60 / 0 0 30 20

TFX WATCHES/WARNINGS/ADVISORIES

Red Flag Warning until 9 PM MDT Saturday for Central and Eastern Lewis and Clark National Forest Areas-Chouteau and Fergus Counties-Eastern Glacier/Toole/Central/Eastern Pondera/Liberty- Hill and Blaine Counties-Lewis and Clark National Forest Rocky Mountain District-Rocky Mountain Front.

Heat Advisory until 9 PM MDT Sunday for Beaverhead and Western Madison below 6000ft-Canyon Ferry Area-Eastern Glacier, Western Toole, and Central Pondera-Eastern Pondera and Eastern Teton- Eastern Toole and Liberty-Gallatin Valley-Gates of the Mountains- Helena Valley-Madison River Valley-Meagher County Valleys- Missouri Headwaters.

Extreme Heat Warning until 9 PM MDT Sunday for Bears Paw Mountains and Southern Blaine-Cascade County below 5000ft-Fergus County below 4500ft-Hill County-Judith Basin County and Judith Gap-Northern Blaine County-Western and Central Chouteau County.