textproduct: Pocatello

KEY MESSAGES

- Freeze Warning this morning. Cold temperatures at night will again challenge the freezing mark tonight and Sunday night.

- Weak low pressure over the northern Rockies and the Great Basin continue to threaten very light precipitation

- Slow warming will get temperatures near normal on Tuesday.

DISCUSSION

Issued at 149 AM MDT Sat Apr 25 2026

Today through Mon night...Deep, nearly stationary, upper level low is positioned over south central Canada. Short waves continue to enter the west side of the pattern and extend upper level troughing far enough west to affect central and eastern Idaho. There is a very weak low off the CA coast that will be brought eastward with a moderate amount of moisture when it phases with a shortwave entering the deep Canadian low. This motion occurs tonight. The end result is the some moisture in the southern low moves into the northern Great Basin, with the deterministic GFS keeping most of the moisture from this source south of the Snake River. Meanwhile, very light precipitation develops along the Continental Divide at the same time. The northern troughing appears stalled over western MT and central ID all the way until Mon evening. This continues to produce light precipitation at least somewhere in the forecast area.

The deterministic models available to look at have very different solutions on the timing and amounts of precipitation; many amounts in any 6 hour period are trace to 0.03. Only the southeast corner around the Bear Lake basin have larger amounts; there is some timing consistency there with the largest event during the day Sun. Expect morning snow and afternoon low elevation rain and high elevation snow.

Overnight lows are hovering in the lower 30s for much of the Snake River plain and eastern Magic Valley. Would expect some cold temperature product to highlight the condition, but at this time unsure if it will be a Freeze Warning or a Frost Advisory. Other locations are not under the Freeze-Frost program, so it is not a consideration. These other locations are mostly in the mountains and temperatures in the teens and 20s are expected at night.

Tue through Fri...The Canadian low IS nearly stationary--which means it is moving slowly. By Wed it should be far enough east to reduce the troughing overhead. Clouds decrease, and the strong spring sunshine should allow warming to near normal for highs and lows, which for example would be mid 30s and low 60s for Pocatello.

The last breezy day with this upper level troughing pattern is Tue, then much lighter wind as eastern Idaho sits between two lows until Fri afternoon at the earliest when the Pacific Northwest low shifts eastward.

Again, about 75 percent of the solutions have patterns that are dry after Tue evening, while the other 25 percent or so keep this troughing over eastern Idaho.

AVIATION /06Z TAFS THROUGH 06Z SUNDAY/

Issued at 1011 PM MDT Fri Apr 24 2026

Skies are clearing with light winds expected overnight into Saturday morning. Winds should remain light on Saturday with some mid to high level clouds arriving Saturday Night.

PIH WATCHES/WARNINGS/ADVISORIES

Freeze Warning until 10 AM MDT this morning for IDZ051>055.