textproduct: Pocatello

KEY MESSAGES

- Persistent north wind will create hazardous conditions on the American Fall Reservoir nearly all day. Lake Wind Advisory in Effect.

- Warming and drying start Sunday, continues through Tuesday afternoon.

- Air flow shifts Monday to southwesterly to westerly, with windy conditions by Wednesday.

DISCUSSION

Issued at 145 AM MDT Sat Jun 13 2026

Trough in WY slowly progresses eastward. This will keep air flow northwesterly, bringing cool and dry air from central Canada. This northwesterly flow continues into Mon. The next trough slides through central MT, shifting the air flow to a more southerly component, allowing some stronger warming by Mon, even stronger Tue. After the trough passes, temperatures cool down slightly for Wed and Thu, then a return to warming for Fri.

The cloud cover expected today is limited to the northern half, and only for a brief period. Coverage is also not extensive, and except for the extreme northeast corner of the forecast area in Fremont County, the forecast is dry today and everywhere else from tonight through Friday afternoon at least. One benefit of the dry conditions is that there is no risk of thunderstorm activity.

The wind in the Snake River plain is expected to be northeasterly all day today; there is a lower threshold for a Lake Wind Advisory when the wind direction is northeast, of 8KT. The northeast wind is even stronger Sun. A Lake Wind Advisory will be necessary both days for the Reservoir. The shift to southwest to west wind occurs during the day Mon, when wind will be lightest and follow slope-valley behavior. The trough moving through MT will increase wind to Advisory-level on Tue afternoon and again on Wed. Thu and Fri will see decreased wind as this trough continues its eastward progression.

AVIATION /06Z TAFS THROUGH 06Z SUNDAY/

Issued at 900 PM MDT Fri Jun 12 2026

VFR conditions are still expected. Gusty east to northeast winds will impact PIH, IDA, and BYI. The typical diurnal wind switch at SUN is still expected in the afternoon despite the overall wind flow across eastern Idaho. That said, it is likely that SUN will go variable versus northwest tomorrow evening.

FIRE WEATHER

Issued at 145 AM MDT Sat Jun 13 2026

In the post-trough environment, cooler afternoon temperatures will result in slightly high afternoon humidity, and the northeasterly flow that sets up over the region will be lighter than Friday. Another trough, this one tracking similarly through western and central MT, will not provide much moisture this far from its center, but will kick up wind strong enough to be a major concern by Tue. If there is little increase in humidity or decrease in temperature, then critical fire weather conditions can be expected for the second half of the work week. As it looks now, a large area of low elevation locations and the southern Sawtooth NF and portions of the Caribou NF will fall into this category.

PIH WATCHES/WARNINGS/ADVISORIES

None.