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 Monday, otherwise dry until Wednesday afternoon

- Breezy conditions expected Monday and Wednesday

DISCUSSION

Issued at 1226 PM MDT Sun May 10 2026

The race is on for those of us who haven't hit 80 for a high temperature this year, and also hit 90. Most locations will cross the finish line, so to speak, by Wednesday across eastern Idaho. High pressure holds tough until then, except briefly tomorrow. A weak low passing by will briefly knock down the ridge, which for the most part helps kick up some wind. All of the models hint a chance of a shower or storm along the Montana border, through Island Park, and into Yellowstone and Tetons mid afternoon through early evening. There is even a hint along the Utah border. It seems more plausible for SOMETHING to form up north, so we did include the potential for isolated development there. In all honesty, it will likely be virga, but we thought it was prudent (as well as surrounding offices) to include a mention. Otherwise, Tuesday and most of Wednesday looks storm- free. This pattern, especially with some help downslope tomorrow and Wednesday will drive temperatures up rapidly. We should see widespread 70s and 80s in the valleys tomorrow, with widespread temperatures in the 80s and low 90s for lower elevations Tuesday and Wednesday. If you look at some of the probability information for highs in the Blend of Models, we still might be a couple of degrees cooler than the highest end of forecast ranges suggest. This is especially true for Wednesday if we end up with a lot more sunshine. IF we end up with more sun or at least some help from downslope winds, some places may indeed hit 95 degrees. It is a low chance, but still a chance. With the low passing by tomorrow, winds do increase with a brief period of hitting WIND ADVISORY thresholds around Craters and across the INL. At the moment, is there is not enough potential there to issue an advisory. We see winds pick up again Wednesday as high pressure slips east and ahead of the next low moving inland. Right now, we appear short of hitting any thresholds for wind-related headlines.

For Wednesday evening onward...the best chance early on for storms will be the central mountains and along the Montana border. We COULD see a few showers or storms elsewhere, but the chance is really low right now. There is a better chance overall Thursday into Friday. The timing on when the potential drops off depends on how quickly the low moves east of the Rockies. For Thursday, a super majority of the cluster forecasts are on the slower side and keep the low still west of Idaho. Meanwhile, the current versions of the GFS and ECMWF already have the low crossing into or across the state and into the Plains by Friday afternoon. The cluster forecasts are more evenly split between speeding up low's progress or still keeping it across or still west of the state. All of the cluster forecast and models agree that the first low is out of our hair, but another area of strengthening low pressure moves in for next weekend. This will keep temperatures cooler and a continued chance of precipitation around.

AVIATION /06Z TAFS THROUGH 06Z TUESDAY/

Issued at 1017 PM MDT Sun May 10 2026

Expect VFR conditions through the period. High pressure today will bring clear skies and overall light winds through this evening into early tomorrow morning.

A weak wave or trough will move through the high pressure ridge tomorrow morning into tomorrow afternoon bringing mid to high level clouds, especially for SUN, IDA and DIJ. No precipitation is expected tomorrow with this trough for all sites except DIJ. Have put in vicinity showers for DIJ for tomorrow afternoon. HREF thunderstorm chances are less than 20 percent currently for tomorrow afternoon for DIJ. Expect wind gusts of 20 to 25 kts for all TAF sites by late tomorrow morning and, especially, by tomorrow afternoon.

PIH WATCHES/WARNINGS/ADVISORIES

None.