textproduct: Great Falls

KEY MESSAGES

- Areas of fog this morning across SW MT.

- Trending warmer as snow continues to melt.

- Above average temperatures Friday into the weekend, with breezy winds returning in most areas Saturday.

DISCUSSION

/Issued 254 AM MDT Wed Oct 14 2026/

- Meteorological Overview:

Upper level ridging will begin building into the region through the day today as an upper level low over CO and an open wave across SK both continue eastward. Lingering low-level moisture across SW valleys is resulting in a mix of low clouds and fog early this morning. The fog and low clouds look to slowly diminish through the day. Temperatures will remain on the cooler side in these area, particularly where a considerable snowpack remains.

Temperatures trend warmer toward the end of the week as upper ridging remains in place. A fast moving shortwave flattens the ridge Saturday afternoon into the evening, which is a favorable pattern for gusty winds across the region. This time is no exception, with forecast soundings in the Cut Bank and Browning areas showing gusts in excess of 50 mph by Saturday afternoon. Trends will be monitored here with respect to the timing and location of the fast moving shortwave. A slower moving wave would be less favorable for the strongest gusts being realized at the surface while a faster moving shortwave would be more conducive to more widespread stronger gusts. Additionally, there are some guidance members that take the bulk of the shortwave north of the International Border which would trend winds down if that scenario were to be realized.

The aforementioned shortwave departs Sunday morning, with transient upper level ridging quickly building back in. This ridging does not last long however, as large scale upper level troughing is strongly favored to move on shore across the west coast Monday. There is considerable uncertainty with respect to the track it will take, however. The main takeaway at this point is for at least a low chance for precipitation returning by Monday night. That said, there will be a bit of volatility in the forecast toward the middle of next week until confidence builds in how the system will progress. -AM

- Forecast Confidence & Scenarios:

Winds Saturday:

Probability for 58 mph wind gusts has trended upward by about 10% for Cut Bank and 20% for Browning over the past 24 hours or so (to 25% and 55% respectively). While confidence is increasing in the stronger winds, there remains some timing and location differences in the system responsible for the gusts that will strongly play into just how strong the winds get.

Troughing next week:

Cluster guidance is essentially unanimous in upper level troughing moving in across the west coast early next week. Confidence rapidly wanes after that however, with guidance showing many potential scenarios. Most show a cutoff low somewhere near the Southwest US, though its exact location will have significant play into whether the area sees precipitation or not. Additionally, several deterministic models send additional shortwaves in from the Pacific NW and vicinity at the same time that the clusters are not able to resolve. This further adds to the complexity of the forecast. As mentioned prior, the main takeaway for this timeframe is for at least a low chance for precipitation. Confidence is far too low to say anything more than that at this time. -AM

AVIATION

14/12Z TAF Period

Main concern this TAF period will be for a mix of fog and low clouds across SW MT this morning. Additionally, a few instances of LLWS will be possible at KCTB this morning before daytime mixing ensues. The fog/low clouds and LLWS diminish through the morning leading to a benign remainder of the day. A front moving across portions of the plains late tonight will result in a wind shift, but there is uncertainty with how far south this wind shift makes it. -AM

PRELIMINARY POINT TEMPS/POPS

GTF 53 31 51 34 / 0 0 0 0 CTB 51 27 47 27 / 0 0 0 0 HLN 55 29 56 30 / 0 0 0 0 BZN 49 25 56 23 / 0 0 0 0 WYS 57 20 58 18 / 0 0 0 0 DLN 50 26 55 26 / 0 0 0 0 HVR 59 29 54 24 / 0 0 0 0 LWT 51 31 52 32 / 0 0 0 0

TFX WATCHES/WARNINGS/ADVISORIES

Dense Fog Advisory until noon MDT today for Canyon Ferry Area- Gallatin Valley-Missouri Headwaters.