textproduct: Great Falls

KEY MESSAGES

- Periods of rain/snow/isolated thunderstorms will continue into Wednesday.

- Below normal temperatures will continue through Wednesday as well.

- Temperatures might go above normal by Friday, but cooler temperatures and a chance for showers return by Sunday.

UPDATE

/Issued 805 AM MDT Sun Apr 26 2026/

805 AM Update...Mid- level shortwave energy combined with cold, upslope easterly flow is supporting an area of steady snow along the Rocky Mountain Front and the north-central plains. Accumulating snow efficiency and associated impacts continue to be most significant over the plains and foothill adjacent to the Northern Rocky Mountain Front, with more scattered impacts to the south and east.

The winter weather advisory will continue through noon for the most impacted areas and a special weather statement was sent out to address the minor winter impacts elsewhere. This area of snow will slowly move southward and become more showery in nature as the day progresses. Additionally, diurnal heating will begin to preclude roadway accumulations. Pops were raised through this afternoon to match up with current trends. - RCG

425 AM Update...Updated morning forecast to increase pops over Chouteau County early this morning. A band of snow has set up, mainly between Fort Benton and Box Elder. This band of snow should start to decrease after 6 AM. Brusda

DISCUSSION

/Issued 805 AM MDT Sun Apr 26 2026/

- Meteorological Overview: A slow moving upper level low over central Canada, with a large circulation, will continue to affect the weather over the CWA for the next several days. Cool air aloft, combined with daytime heating will allow for scattered rain/snow showers to develop daily through at least Wednesday. The overall precipitation amounts will be on the light side, but some short periods of accumulating snow are likely through Monday. There will be just enough instability during the afternoon hours that some isolated lightning strikes will also be possible. Overall, below normal temperatures will continue daily through Wednesday, with today and Monday being the coolest days.

For Thursday through Sunday...the upper level low in Canada will move off to the east, as a new upper level trof begins to move southward along the Pacific coast by Saturday. This trof will influence the weather over our CWA, with a moist southwesterly flow aloft developing. This will result in warmer air pushing northward into the CWA, but also allow for scattered showers or event a thunderstorm to move back into the CWA by Sunday.

- Forecast Confidence & Scenarios: The winter weather advisory will continue through the morning hours over the Northern Rockies and in the Browning area.

Another round of light snow will affect the Central and Southern portions of the CWA tonight into Monday. At this time, I only have about an inch or two of snow accumulations on the mountain passes, thus holding off on an advisory for now. It is looking more likely that an SPS will be needed for Sunday night into Monday. Brusda

AVIATION

26/18Z TAF Period

Shortwave energy and a moist low level easterly flow will maintain low stratus, mountain obscuration and periods of light snow over north- central and southwest MT for much of the period. The focus of the snow will shift into southwest MT after 26/21Z, but MVFR/IFR stratus will linger for most terminals through Monday morning. - RCG

PRELIMINARY POINT TEMPS/POPS

GTF 38 22 48 28 / 90 20 30 10 CTB 34 13 46 22 / 90 10 10 0 HLN 42 24 49 28 / 40 30 50 10 BZN 46 25 46 25 / 40 50 70 20 WYS 44 20 43 20 / 60 70 80 40 DLN 49 27 47 27 / 30 50 60 10 HVR 41 18 48 25 / 50 10 10 10 LWT 38 20 43 23 / 60 40 50 20

TFX WATCHES/WARNINGS/ADVISORIES

Winter Weather Advisory until noon MDT today for East Glacier Park Region-Northern High Plains.