textproduct: Great Falls

KEY MESSAGES

- Patchy fog is possible this morning along the Milk River Valley.

- Above normal temperatures and generally dry conditions are expected through the rest of the Labor Day weekend.

- Wildfire smoke may impact air quality at times across portions of central and southwest Montana today and tomorrow.

UPDATE

Today it will be warm and mostly dry across North-central, Central, and Southwestern Montana. For the update Pops this afternoon were slightly increased across North-central and Central Montana to reflect the latest hi-res model guidance. The rest of the forecast is on track. -IG

DISCUSSION

/Issued 427 AM MDT Sun Aug 31 2025/

- Meteorological Overview:

Upper level ridging will continue through Tuesday allowing for near to above normal temperatures and generally dry conditions to continue across the region. By Wednesday into Thursday a strong upper level low starts to move down from Manitoba into the Great Lakes region which will compress and shift the ridge to the west. This will allow for some slightly cooler temperatures through the end of the work week. Overall, dry conditions are expected, however, an isolated afternoon shower or thunderstorm cannot be ruled out. By next weekend the low moves further east allowing for the ridge to start to flatten a bit which will lead to increasing chances for precipitation, particularly across southwest Montana.

- Forecast Confidence & Scenarios:

A combination of wildfire smoke from Washington, Idaho, and Montana will filter across central and southwest Montana today and tomorrow. Currently, the worst of the near-surface impacts are expected this morning where the main concern will be degraded air quality.

There are hints in the latest run of the HRRR-smoke that some wildfire smoke from Canada may make a push south tomorrow afternoon. However, at this time, the greatest impacts are expected east of our area. -thor

AVIATION

31/12Z TAF Period.

Generally VFR conditions will prevail over the CWa through the period, with a few minor impacts.

Some patchy fog could develop in the Havre/Harlem by morning, generally thinning out by 16z.

Smoke will affect areas along the divide and across Southwest MT through the period. Overall visibility will generally be better than 6SM, some areas might have visibility reduced to less than 10SM, along with mountain obscurations. Brusda

Refer to weather.gov/zlc for more detailed regional aviation weather and hazard information.

PRELIMINARY POINT TEMPS/POPS

GTF 88 55 90 55 / 0 0 0 0 CTB 86 51 88 52 / 0 0 0 10 HLN 87 57 88 57 / 0 0 0 0 BZN 85 50 88 51 / 0 0 0 0 WYS 77 38 79 38 / 0 0 0 0 DLN 82 47 84 48 / 0 0 0 0 HVR 86 55 87 56 / 0 0 0 0 LWT 82 55 84 53 / 10 0 0 10

TFX WATCHES/WARNINGS/ADVISORIES

None.