textproduct: Pocatello

KEY MESSAGES

- Lingering showers and thunderstorms into this evening, along with southwest winds gusting to around 45 mph in the Snake Plain.

- Gusty west winds crank up again on Wednesday and expand into the Eastern Magic Valley and Southern Highlands.

- Cool overnight temperatures tonight and especially Wednesday night, with Frost Advisories/Freeze Warnings likely needed for the valley growing zones Wednesday night.

- Drying and warming trend along with periods of breezy conditions later in the week through the weekend.

DISCUSSION

Issued at 128 PM MDT Tue Jun 9 2026

Early afternoon water vapor imagery shows a negatively-tilted upper trough continuing to make its way east across the Northern Rockies. While the stronger dynamics ahead of this system have shifted east of the area, cool temperatures aloft in the trough axis combined with afternoon surface heating have yielded adequate instability to support scattered showers and thunderstorms. Latest SPC mesoanalysis data and HREF progs indicate areas of SBCAPE around 500 J/kg along with deep layer shear magnitudes around 30 kts, supportive of a few stronger storms capable of producing small hail and gusty winds up to 50 mph. Any remnant showers/storms will quickly taper off after sunset, with clearing skies and diminishing winds setting the stage for a cooler night, although overnight lows look to stay just warm enough to alleviate any widespread frost concerns over the lower elevation growing zones.

Temperatures on Wednesday stay on the cool side as a reinforcing mid/upper-level shortwave pivots south across MT/ID on the backside of the broader trough making its way east across the Northern Plains. Afternoon highs will remain about 10 degrees below average, reaching the 60s in the valleys and 40s/50s mountains. This shortwave will support some shower/thunderstorm chances (20-50 percent) over the Central Mountains east into the Island Park area and Eastern Highlands where better forcing and moisture align. West winds will also crank up again on Wednesday, gusting up to 50 mph, in the tightened pressure/height gradient ahead of this shortwave and attendant surface cold front. Cold temperatures are on tap for Wednesday night into Thursday morning as surface high pressure builds into the area with clearing skies and light winds overnight leading to good radiational cooling of the post- frontal airmass. Freeze Warnings and Frost Advisories are anticipated for our lower elevation growing zones where lows are forecast to drop solidly into the 30s. The interstate corridor from Burley to Pocatello to Idaho Falls remains slightly warmer with mid to upper 30s forecast. Probabilities of temps lower than 36F are around 35 percent at Burley, 45% and Pocatello, and 65% at Idaho Falls per latest NBM guidance. Elsewhere across the Snake Plain and Magic Valley, low to mid 30s look to be the rule, with probabilities of temps less than 36F exceeding 70 percent over most of this area. Looking at probabilities of less than 32F, the highest values in the lower elevation growing zones extend from the upper Snake Plain to west of Blackfoot and the Arco Desert, where probabilities reach as high as 50-75 percent. Those with gardens or other sensitive vegetation will want to take protective measures Wednesday night.

A warming trend starts Thursday as upper ridging builds off the West Coast, leading to rising heights locally beneath northwest flow aloft. Will see temperatures rebound to near normal on Thursday, before climbing above normal Friday though the weekend into early next week. Predominantly dry conditions look to prevail Thursday through early next week. A shortwave trough dropping through the northwest flow aloft may glance the area in the Saturday night/Sunday timeframe, which could bring shower chances to the Divide and Island Park area. Better moisture and precip chances currently appear to remain east of the area, but seeing quite a bit of spread in ensemble clusters with the depth and westward extent of this feature so stay tuned. Afternoon breezes pick back up Friday and Saturday, which combined with warming and drying, will bring some renewed at least low-end fire weather concerns to parts of the Snake Plain, Eastern Magic Valley, and South Hills.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1122 AM MDT Tue Jun 9 2026

Midday satellite imagery shows a mix of sun and clouds across eastern Idaho as a band of showers departs east into Wyoming. Rain-cooled air and increased sunshine this afternoon should be enough to generate additional showers and isolated thunderstorms fueled by the low-level instability. We're not expecting many impacts with the thunderstorms, but stronger cells could generate brief, gusty winds or small hail. Initially this could briefly impact BYI then PIH and DIJ through the afternoon.

Outside of the showers and isolated thunderstorms this afternoon, we're seeing ambient wind speeds increasing over the Snake Plain and adjacent valley locations. Skies will generally be on the clearing trend this evening into the overnight as residual moisture erodes away. Drier air is expected to move in Wednesday, brought in by increasing surface flow near what we're seeing this afternoon. Gusty winds will linger through the day again Wednesday before subsiding in the evening.

FIRE WEATHER

Issued at 136 AM MDT Tue Jun 9 2026

Today expect strong winds gusts (35 to 50 mph) with increased RHs (min RHs of 25 to 60%) with scattered showers and isolated thunderstorms with wetting rains possible for higher elevations. Precipitation chances continue into Wednesday mainly for Fire Weather zone 411 with a weak shortwave dropping over our northeastern areas. Expect gusty winds Wednesday as well with gusts of 25 to 45 mph likely. High temperatures will be in the 50s and 60s today and Wednesday.

Look for drying and warming trends along with breezy conditions Friday through the weekend. Temperatures will rise back to the 70s and 80s for daytime highs. Min RHs will drop back below 25% across the area for mountain areas and below 15% for the Snake Plain, Eastern Magic Valley and our southwest areas (fire weather zones 410, 425, 427, and portions of 413).

PIH WATCHES/WARNINGS/ADVISORIES

Wind Advisory from 9 AM to 9 PM MDT Wednesday for IDZ051>058- 062. Wind Advisory until 9 PM MDT this evening for IDZ052-053.