textproduct: Pocatello

KEY MESSAGES

- Red Flag Warning in the Snake River plain and Teton Valley noon to 8 PM MDT today for low humidity and gusty wind.

- Breezy to windy conditions continue through Sunday, but higher humidity will eliminate Red Flag conditions.

- Light showers may return to the eastern and southern highlands late tonight into Friday morning. Heavier showers at scattered or lower coverage, and thunderstorms at isolated coverage, for Saturday and Sunday.

DISCUSSION

Issued at 148 AM MDT Thu Sep 10 2026

Today through Sun...Upper level trough moving through southern Canada will dig far enough south to increase wind in southern Idaho today to significant thresholds for Fire Weather. A closed low that develops off the end of this trough slowly meanders onshore and moves through the ID panhandle and western MT Sat night and Sun. Wind appears even stronger on Sun when the close low's southeast corner overlays the entire forecast area.

The closer the low gets, the cooler temperatures will be. Thus today will be the warmest overall. Temperatures cool slightly on Fri, then level off on Sat, then cool down 14 to 20 deg F from Sat afternoon to Sun afternoon.

The trough passing by today does appear to entrain some moisture northward into the southern and eastern highlands in the forecast area by late tonight into Fri morning. A slight chance of thunderstorms develops in the southeast corner of the forecast area. By Sat and Sun, showers and thunderstorms will overspread the forecast area, with Sat having the greatest coverage, then the pattern shifting eastward and mostly out of the central Idaho mountains.

Sun night through Wed...Dry zonal flow sets up in the wake of the upper level low. This will mean are return to warming, getting to near climatic normals by Tue afternoon. The moderate to strong upper level westerly flow will mean gusty afternoons as inversions break. Dewpoints will fall, and so critical fire weather conditions may return for some of the zones during this period.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 524 AM MDT Thu Sep 10 2026

After several days of clear and a million with fairly light wind, a significant change develops in the late afternoon, 11/00Z, give or take an hour. Wind will be taking on a southwest component with G25KT and even later G30KT. Wind stays elevated, except perhaps at KSUN, starting in the early evening.

CIGs stay at mid-level heights around the same time, and SHRA should start developing. Currently, it does not look unstable enough for TS. SHRA may get to consistent -SHRA at the very end of the current TAF valid times.

Not expecting any impact to VSBY.

FIRE WEATHER

Issued at 148 AM MDT Thu Sep 10 2026

An upper level trough moving southward, but staying in Canada, will bring moderate to strong wind for today through Sat, mainly in the afternoon, then a closed low moving in from the west will punch up the wind even stronger on Sun. So overall it will be a breezy to windy four days ahead.

This will combine with very low humidity today, and possibly tomorrow, as humidity expected in some areas to sink below 15 percent. After coordination with dispatch staff, a Red Flag Warning was issued for today in Fire Weather Forecast Zone 410, the BLM lands in the Idaho Falls District.

Over the weekend, the temperatures will cool and humidity spike upward as showers and thunderstorms arrive on account of this closed low. Do not expect any critical fire weather conditions over the weekend as thunderstorm activity should be isolated in coverage.

PIH WATCHES/WARNINGS/ADVISORIES

Red Flag Warning from noon today to 8 PM MDT this evening for IDZ410.