textproduct: Pocatello

KEY MESSAGES

- Monsoon moisture will keep showers and storms around through Wednesday, MAYBE Thursday

- Hotter temperatures and very dry conditions return heading into the weekend, including HeatRisk impacts

- Critical to near-criticial fire weather conditions expected for the next several days

- Wildfire smoke will continue to produce poor air quality especially in areas closer to central and western Idaho

DISCUSSION

Issued at 1219 AM MDT Tue Jul 28 2026

As expected, we are seeing a break in monsoon-related showers and storms early today. That will allow us to be a bit warmer today, and seeing increased instability this afternoon. Of course, smoke will also play a role in this. The latest models keep most of the smoke across areas closer to central and western Idaho, but do occasionally show it drifting into eastern Idaho a bit at times. Where the smoke remains more dense, this will limit temperatures and possibly limited instability. By afternoon and evening, we are expecting two main areas for thunderstorm development. Isolated storms are expected to form from around Mackay through Gilmore Summit through Island Park. There is a 10-40% chance for gusts over 35 mph, peaking in the 40-50 mph range. Rainfall with these storms will remain fairly limited. The other area will be extend across higher terrain south of the Snake River, with some bleedover possible into the Magic Valley and Snake Plain...especially along any outflow boundaries that form. These storms may produce some decent downpours, although total rainfall will not amount to much, and also higher possibilities of wind over 35 mph. There is a 50-90% chance for those types of gusts, peaking in the 40-55 mph range. For tonight, we will see monsoon moisture continue to stream across central and eastern Idaho. We do keep a mention of isolated light showers/virga overnight. We wouldn't be shocked to see a few lightning strikes out of that. For tomorrow, showers and storms will make a resurgence across most of central and eastern Idaho. Current probabilities for gusts over 35 mph are at 30-80%, but will be highly dependent on where we see sunshine later in the day. This may be another situation where morning cloud cover and smoke, may quell the amount of instability we see.

Starting Thursday, hotter and drier conditions will take hold through the weekend. There may be just enough lingering moisture Thursday afternoon for a few storms to fire over higher terrain, but at the moment that chance is less than 15%. We may need to increase that chance in later forecast updates. Otherwise, temperatures peak Friday and Saturday in the mid 90s to mid 100s across the area. With warm overnight lows, this will quickly produce HeatRisk impacts especially to people sensitive to heat or do not have the ability to stay cool and hydrated. There will be a pattern change heading into next week it appears. Low pressure to the north will push the ridge back to our south, with will knock temperatures back 10-15 degrees, but still AT OR JUST ABOVE AVERAGE. The difference here is that the flow will keep monsoon moisture to our south as the flow is more from the west vs southwest. Expect a continuation of very dry conditions across the board even with the pattern change.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1212 PM MDT Tue Jul 28 2026

VFR conditions in place across the region as smoke impacts continue to wane, for now. HRRR smoke model output suggests a return likely around KSUN and KBYI during the overnight and into the hours leading up to sunrise Wednesday. Perhaps this will stretch up to KPIH by mid-morning tomorrow but confidence in specific VSBY reductions remains low. On the flip side, still seeing some potential for SHRA/TSTM impact later this afternoon around KBYI, KPIH and KDIJ based on latest CAM output. Maintained PROB30s accordingly with gusty outflow winds being a distinct possibility. Overnight, we do expect some mid level clouds with next monsoon push. There is the potential for a few light showers/virga and perhaps a thunderstorm, but the chance is way too low to mention at this time. Winds should be light through the period aside from any aforementioned outflow boundaries.

FIRE WEATHER

Issued at 1219 AM MDT Tue Jul 28 2026

For a multitude of reasons, we are looking for critical to near-critical fire weather conditions for the next several days. We do expected another round of thunderstorms later today and into this evening. Isolated storms are expected across Zone 476 and extending along the Montana border through Zone 411. A second area of storms will form across higher terrain across Zones 413 and 427, extending up through the Tetons. Coverage will be borderline scattered down south, but confidence and coordination isn't there to issue a RED FLAG WARNING at the moment. Gusts over 35 mph are possible especially with storms down south. Storms to the north will be mostly dry, with more of a mix down south. We will also be borderline for a warning due to winds and low humidity across the central mountains, with gusts in the 20-30 mph range. We will be watching to see how smoke impacts instability and temperatures today, especially since we are seeing it thin out in some spots. One last surge of monsoon moisture will keep showers, and may a thunderstorm or two, around tonight...increasing during the day Wednesday. Coverage tomorrow will be highly dependent on two things: cloud breaks after morning cloud cover and smoke.

Starting Thursday, we are will see hotter and drier conditions return. We may see a few dry storms over the mountains Thursday, but it looks bone dry after that heading through the weekend and into next week. We will see near-critical conditions Thursday due to wind and low humidity across the mountains. Expect more of the same Friday and Saturday. The bigger impacts those day will likely be a return to hotter temperatures. Crews in the mountains will be in the 70s to near 90. Valley temperatures will be in the mid 90s to mid 100s. Look for increasing heat- related issues during this short stretch. Cooler weather will return starting Sunday, HOWEVER, this pattern change will not bring back monsoon moisture it appears. This is the typical ridge breakdown pattern, as low pressure skirting by brings the cooler conditions, but also stronger winds and a continued very dry airmass in place. Any monsoon push should remain to our south as the flow turns westerly vs southwesterly.

AIR QUALITY

Issued at 1212 PM MDT Tue Jul 28 2026

Air quality has improved across the eastern half of the region and some of the Air Quality Advisories have been canceled accordingly but still linger across the western half which includes the Magic Valley, parts of the Arco Desert and throughout the central mountains. See the alerts from Idaho DEQ for additional information.

PIH WATCHES/WARNINGS/ADVISORIES

Air Quality Alert until 3 PM MDT Wednesday for IDZ051-052- 055>057-067>075.