textproduct: Pocatello

KEY MESSAGES

- Frontal Progression: A cold front continues to traverse the region this morning, maintaining elevated winds and shifting precipitation into a showery phase by midday.

- Winter Weather Headlines: Winter Weather Advisories remain in effect for the Island Park area and Bear River Range through early Friday morning, while headlines for the central mountains are slated to expire later today.

- Convergence Band Potential: High-resolution models suggest a potential convergence band today, which could bring light snow to valley floors but confidence is still low.

- Freeze Warnings: Widespread sub-freezing temperatures in the low to mid-20s are expected tonight and again Friday night. Freeze Warnings are in effect to protect vulnerable early- season vegetation.

- Substantial Weekend Warm-Up: Rapidly building high pressure will usher in a dry weekend, with temperatures soaring into the upper 60s and mid-70s by Sunday and Monday.

DISCUSSION

Issued at 1248 AM MDT Thu Apr 16 2026

A cold frontal boundary is currently pushing through Eastern Idaho, characterized by breezy synoptic winds and broken bands of precipitation. As the front progresses, the steady overnight precipitation is expected to transition into a more showery regime by mid-to-late morning, with rain changing over to snow in many areas as a much colder air mass filters into the region. While travel impacts will begin to diminish in the central mountains later today, Winter Weather Advisories remain in effect through early Friday morning for the Island Park region and the Bear River Range, where mountain snow will be most persistent.

One area of lingering uncertainty is the potential for a convergence band signature appearing on high-resolution models. If this feature develops, it could produce light snow across lower valley floors this afternoon and evening, though accumulations would be minimal. Synoptic winds will remain breezy with gusts up to 30 mph, though generally staying below advisory thresholds. Daytime highs today and Friday will remain quite chilly, ranging from the 30s in the high country to the 40s in the lower valleys.

Once the bulk of the precipitation tapers off, the primary concern shifts to the impending cold. Widespread sub-freezing temperatures are forecast for tonight and again Friday night into Saturday morning. Freeze Warnings remain in effect for the Snake Plain and Magic Valley, where a hard freeze is expected as temperatures drop into the low to mid-20s. While Friday night may be a touch warmer than tonight, a hard freeze remains likely nearly everywhere. These temperatures pose a significant risk to early-season crops and blossoms that have already emerged following a very mild winter.

Relief arrives quickly as we head into the weekend. High pressure will build rapidly over the Intermountain West, ending all precipitation and initiating a significant warming trend. Temperatures will return to seasonal normals on Saturday before soaring well above average by Sunday. Valley locations can expect pleasant highs in the upper 60s to mid-70s for both Sunday and Monday. Looking into early next week, model confidence remains low regarding the arrival of the next Pacific system. Due to continued model struggles with the upper-level evolution across the Pacific Northwest, precipitation chances have been delayed until at least late Tuesday.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 1105 AM MDT Thu Apr 16 2026

Our main area of precipitation continues to slide east of I-15, but is being replaced by showers through this evening. We should see light snow through late afternoon at DIJ. At PIH and IDA, we are seeing virga as even a band of "heavier precipitation" isn't able to overcome dry air and downslope conditions. We do expect a fairly wide range of conditions, bouncing from VFR to IFR especially if we get a heavy shower in place. We are not going any more dire than PROB30 with potential showers, even with a hint of one or more convergence-type bands. Even within those bands, it looks more showery vs solidified bands. Winds will be gusty at 20-35kts, with stronger gusts across the Snake Plain and Magic Valley outside of any showers. Winds will subside overnight but remain breezy at times. We do expect VFR weather tonight and tomorrow morning, except at DIJ where it looks like enough moisture lingers for MVFR/IFR ceilings.

PIH WATCHES/WARNINGS/ADVISORIES

Freeze Warning from 3 AM to 10 AM MDT Friday for IDZ051>055. Winter Weather Advisory until 6 AM MDT Friday for IDZ060-066.