textproduct: Pocatello

KEY MESSAGES

- Record or near record highs possible through Wednesday with afternoon temperatures 20-25 degrees ABOVE AVERAGE

- A few showers possible near Island Park today, otherwise dry until Wednesday afternoon

- Breezy conditions expected today and Wednesday

DISCUSSION

Issued at 254 AM MDT Mon May 11 2026

The main story for the first half of the this week will be well- above normal warmth with the potential to break record highs by Wednesday. With climatological norms running mid- to upper-60s for our valley locations, temperatures over the next several days will run 20 or more degrees above normal. A weak wave will pass to our north today, flattening the ridge of high pressure that is dominating our weather pattern. Even still, daytime temperatures will warm by several degrees as compared to yesterday. HREF members show isolated to scattered showers north of Rexburg late this afternoon through late evening. Isolated thunderstorms are also possible during this timeframe, with HREF probability of thunder up to 20 percent in the aforementioned region. Winds will increase this afternoon, with sustained winds across much of the Snake River Plain and Arco Desert reaching around 25 mph. There is a marginal chance for Lake Wind Advisory conditions on American Falls Reservoir later this afternoon/evening, during which time southwest winds could briefly reach low-end criteria at 20 mph, especially across the northern extent of the reservoir. The National Blend indicates a 25- 50% chance of reaching that criteria across the reservoir between 4 and 8 PM today.

The ridge of high pressure will quickly rebound tomorrow, allowing temperatures to continue to warm. Many low elevations areas will warm to around 90 degrees Tuesday and/or Wednesday. By mid-week, we will begin to feel the influence of a Pacific closed low which will move onshore and inland Wednesday, shifting the area of high pressure further east. Winds will increase again Wednesday afternoon, with gusts ranging 30 to 45 mph across Southeast Idaho. Chances for showers and thunderstorms will become increasingly more widespread as the next low pressure system shifts east and temperatures will run relatively much cooler the latter half of the week.

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 521 AM MDT Mon May 11 2026

VFR conditions forecast areawide. Shortwave working through to our north will bring high clouds and breezy winds today. 20 to 30 kt gusts are forecast at all terminals. Have retained VCSH at KDIJ this afternoon with confidence in a direct shower and/or thunderstorm too low to include in the forecast (less than 20% chance).

PIH WATCHES/WARNINGS/ADVISORIES

None.