textproduct: Great Falls

KEY MESSAGES

- Warm and breezy today with scattered showers and isolated thunderstorms with gusty winds this afternoon and evening.

- Cooling back to seasonal Sunday through early next week with more widespread showery conditions and some high elevation snow later Sunday and Monday.

- Potential for a stronger storm mid to late next week with windy conditions followed by much cooler temperatures and precipitation

DISCUSSION

/Issued 502 AM MDT Sat Apr 11 2026/

- Meteorological Overview:

An upper level trough moving onshore along the west coast will continue inland through the weekend, bringing a shift to increasingly showery conditions by late Sunday. Breezy to windy conditions develop today beneath increasing southwesterly mid level flow as the trough approaches, which also pushes temperatures well above average today with most lower elevation locations seeing afternoon temps in the 70s. Showers and a few thunderstorms are likely to develop initially this afternoon across western MT and ID then track northeast across most of north-cntral and SW MT through this evening as an initial shortwave disturbance lifts out of the trough across the state. In addition to the general breezy to windy conditions developing this afternoon, the convective nature of showers and any thunderstorms through this evening could bring some brief stronger gusts with winds becoming more westerly tonight behind the disturbance.

The larger scale trough moving inland opens up with several weaker waves of energy lifting across the area Sunday and Monday. These are not particularly organized features but the additional moisture and lift will lead to a greater coverage of showers later Sunday through Monday with a focus for more persistent showers/precipitation across central MT. Temperatures cool back to seasonal averages Sunday through early next week with snow levels lowering to around 6000 ft Sunday night and possibly a bit lower across north-central MT Monday morning as some lower-level cool is drawn south from Canada across the plains. This still looks to limit any potential for impactful snow accumulation Sunday/Monday to elevations above most highway mountain passes.

A brief lull between systems is likely Monday night through Tuesday before a more potent upper level trough digs south from the Gulf of AK into the NW US by Wednesday. While there is still the typical uncertainty at this time range, this is a much colder trough with potential for strong winds preceding its arrival Wednesday before a shift to below average temperatures and potential for widespread precipitation, including lower elevation snow by Thursday. Hoenisch

- Forecast Confidence & Scenarios:

Precipitation amounts in the Sun-Mon period have not significantly changed with a 30-60% probability for QPF in excess of 0.50" across central MT with highest probabilities across the central MT mountains. While lighter precipitation amounts are expected further north along the Hi-line and for areas south of I-90, wetting precipitation is expected with most areas having a 60% or higher probability of at least 0.10" precipitation. Hoenisch

AVIATION

11/18Z TAF Period

Scattered showers and isolated thunderstorms will begin to develop this afternoon across Southwest MT and the North-Central MT plains. Showers/thunderstorms can bring brief MVFR conditions if a moderate shower develops over the terminals. At KCTB and KHVR, there's lesser confidence showers reach the terminals. The main hazards with thunderstorms will be gusty outflow winds. Across Southwest MT, breezy synoptic winds continue this afternoon, winding down in the evening. Overnight, MVFR clouds move into the Rocky Mountain Front. -Wilson

PRELIMINARY POINT TEMPS/POPS

GTF 72 39 58 39 / 40 40 40 90 CTB 66 34 51 32 / 20 20 10 30 HLN 69 38 61 37 / 60 60 70 90 BZN 70 36 63 34 / 30 60 70 60 WYS 58 30 54 27 / 70 60 70 60 DLN 67 34 60 34 / 50 50 60 50 HVR 74 40 58 35 / 20 30 10 60 LWT 72 39 60 37 / 30 40 60 90

TFX WATCHES/WARNINGS/ADVISORIES

None.