textproduct: Pocatello

KEY MESSAGES

- Showers and thunderstorms mostly across the central mountains through tomorrow morning

- Better chance of showers and thunderstorms tomorrow evening through Monday for all of central and eastern Idaho

- Breezy conditions through Labor Day expected

DISCUSSION

Issued at 1205 PM MDT Sat Sep 5 2026

The trend still remains for whatever shower and thunderstorm activity is out there through Sunday morning to remain across the central mountains. We will have to watch late this afternoon and evening for the potential for development from Jackpot up through Hailey, which is a little farther south from where the current forecast has things redeveloping. Even if we see that development, it quickly shifts north into the central mountains by late evening. Otherwise, looks for breezy southerly winds. Gusts of 25-35 mph will be common through this evening, lingering across the southeast highlands up through the Teton Valley with downsloping into the Snake Plain from Pocatello north. The main issues remain for tomorrow night and Labor Day - increasing showers and thunderstorms followed by stronger winds late in the day. We may catch a small amount of moisture from Marie closer to the Wyoming border, but amounts even with that possibility continue to drop off. The best chance of rainfall looks more and more plausible over portions of the central mountains associated with low itself. Most areas now will only see a few hundredths to around 0.30", including in the mountains. We may see up 0.50" across higher elevations of the eastern highlands, with a 30-50% chance of exceeding that amount. Areas north of Stanley and through the Frank Church are looking at 0.40-0.70" with the latest forecast, with a 40-60% chance of more than 0.75". Showers and storm will clear most areas by afternoon except for the central mountains and along the Montana border, and all areas by midnight. Winds ahead of showers and storms tomorrow will be out of the south and southwest at 15-30 mph (sustained and gusts) with some spots seeing gusts around 35-40 mph. Adding in potential gusts with storms, we could see outflow winds approaching 50-60 mph tomorrow afternoon and evening. There is a MARGINAL RISK for severe storms over most of eastern Idaho for this reason. On Labor Day, winds will be west to southwest...strongest from the Magic Valley up into southwest Montana. Sustained 25-35 mph with gusts above 40 mph are possible, pushing WIND ADVISORY thresholds across the Arco Desert. There will be a very sharp contrast tomorrow vs Monday with temperatures. We will 70s and low 80s for highs in the valleys Sunday. Monday will be 10-15 degrees COOLER with only a few spots possibly getting above 70. It will be cold enough Monday with the low crossing the central mountains to see a rain/snow mix or brief period of all snow for elevations above 10,000ft!

Tuesday looks dry, and so does most of Wednesday. (We might see a few random showers in the afternoon). There is a slightly higher chance of showers and storms Thursday, but likely increases steadily into next weekend. Temperatures rebound with 70s and 80s quickly returning at the end of the upcoming week.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/

Issued at 1146 AM MDT Sat Sep 5 2026

A weak shortwave feature will produce another low chance of light SHRA at KSUN overnight, otherwise quiet VFR conditions are expected at all sites. Looking ahead to late Sunday, an approaching upper level low will increase southerly flow across the region, bringing an increase in moisture and clouds late in the day, with precipitation chances increasing into the overnight.

FIRE WEATHER

Issued at 1205 PM MDT Sat Sep 5 2026

Showers and isolated thunderstorms will remain across the central mountains through tomorrow morning. Amounts should remain light, with a few stronger storms MAYBE producing locally heavier rainfall. Outside of that, looks for gusty winds and the potential for near-critical to locally critical fire weather conditions due to marginal humidity. We have seen a few spots across Zones 410, 413, and/or 427 occasionally pushing into criteria for a handful of hours each day. That trend continues across Zone 413 and perhaps 410. Ahead of the moisture push tomorrow, we will likely see this across Zones 410, 425, and 427. With very limited impact from Marie in terms of rainfall amounts tomorrow and Labor Day, totals have continued to drop outside of the central mountains where higher amounts persist with the low moving through the area. Most areas will see anywhere from a few hundredths to around 0.30" including higher elevations. The exceptions will be along the Montana border in Zone 411 and north of Stanley through the Frank Church into Lemhi County in Zones 422 and 475. For Zone 411, look for up 0.50" with a 30-50% chance of exceeding that amount. For Zone 422 and 475, look for 0.40-0.70" with the latest forecast, with a 40-60% chance of more than 0.75". It does appears a brief period of snow or a mix is expected Monday across the central mountains above 10,000ft. We may stronger storms producing gusts over 35 mph with some potential for gusts of 50-60 mph. On the back side of the low Monday, stronger west to southwest winds will develop mainly across Zones 410 and 425 with gusts of 35-45 mph are possible. It will breezy elsewhere, but not as strong.

Dry conditions return for midweek with temperatures quickly rebounding. Showers and thunderstorm chances pick up again toward the end of next week.

PIH WATCHES/WARNINGS/ADVISORIES

None.