textproduct: Pocatello

KEY MESSAGES

- Snow showers through Mon limited to northwest side of central Idaho mountains and the upper Snake River highlands.

- Significant warm winter storm should arrive late Monday afternoon, peaking in intensity late Monday night and Tuesday morning.

- Light showers continue through to at least Friday afternoon.

DISCUSSION

Issued at 127 AM MST Sun Feb 15 2026

Today through Tue night. Upper level high still dominates, but embedded shortwaves move through the north end of this ridge, mainly through the Idaho panhandle and west Montana, but on the extreme southern edge occasional flurries or light snow can be expected in areas northwest of passes like Galena Summit and Gilmore Summit, and in areas north and east of Rexburg. This all changes Mon night as a deep upper level trough moves onshore. The southerly wind ahead of the trough axis will pump warm moist air into all of southern Idaho. Some guidance has as much liquid water equivalent in precipitation of 0.50 of an inch, which, if snow, could be an inch per hour over a six hour period. This is mostly in the mountains, of course; total liquid water equivalent in a 24 hour period at the Pocatello airport is right around 0.25 of an inch for the bulk of the storm. This is likely at that elevation to be rainfall, with most snow accumulations staying at 5500ft elevation or higher for those first 24 hours. Lighter, more showery activity develops for Tue night; temperatures cool at this point and snow is to be expected all the way down to Snake River plain locations.

Temperatures will be hovering close, but not quite at record level for the afternoon highs today and Mon, but with the evaporative cooling in precipitation and the abundant cloud cover, Tue highs will be down 10 to 15 deg F compared to the previous day. Cloud cover at night will have the opposite effect on the lows, keeping them more mild until Tue night when below freezing temperatures return to the Snake River plain and eastern Magic Valley.

Wind wil continue to increase each afternoon, from day to day, then Mon night should be some of the windiest conditions, but right now appears to stay below Wind Advisory levels.

Wed through Sat...Behind this winter storm an upper level trough becomes nearly stationary over western Canada. This keeps troughing over the forecast area and a risk of precipitation in the much colder conditions, even for the Snake River plain locations. The lone break in the weather may be Fri night and Sat, at the very end of this forecast.

For the first time in a long time, forecast temperatures are expected to be below normal for the time of year, barely warming to around freezing each day in this period. Overnight lows for Pocatello linger around the upper teens. Stanley basin will linger right around the zero mark, with highs 9 to 15 deg F cooler than normal.

Wind continues elevated, in the breezy/brisk to windy category during this time as well.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 353 AM MST Sun Feb 15 2026

A mid-level deck around 6000ft to 8000ft AGl is expected to hold for most of the period for a BKN-OVC CIG, with a few clouds both above and below this in the morning, but it should be reduced to just this layer during the afternoon. No impacts to VSBY and all CIGs should be solid VFR.

Wind will increase and take on a more southerly component, and even get gusty at KBYI as a deep upper level trough makes an approach, arriving here Mon night. KBYI has southerly gusts as strong as 25KT for a while during the late morning/early afternoon. The only exception is KSUN, where slope-valley wind phenomenon will still continue.

PIH WATCHES/WARNINGS/ADVISORIES

None.