textproduct: Pocatello

KEY MESSAGES

- Wildfire smoke will continue to impact the area on and off for the next few days. Expect decreased air quality at times with an air quality advisory remaining in effect for Custer County.

- Heat Advisory continues for the eastern Magic Valley, South Hills, and Snake River Plain for the weekend as highs remain in the mid to upper 90s.

- Very small chance for an isolated shower or storm this afternoon, mainly in the South Hills.

DISCUSSION

Issued at 209 AM MDT Sat Aug 8 2026

The heat is the main weather impact this weekend with a HEAT ADVISORY continuing for the eastern Magic Valley, South Hills, and Snake River Plain. It's within these areas that highs today will push towards 100 degrees again and only drop into the low to mid 60s overnight into Sunday. Some wildfire smoke lingers across the area today, but the main impacts from that are expected to be a bit more confined to Custer County where an Air Quality Alert remains in effect through Monday afternoon. In addition to the heat and smoke, a RED FLAG WARNING is also in effect for the Central Mountains this afternoon. This is due to gusty afternoon winds around 25 mph and minimum relative humidity falling to 10 to 15 percent. Outside of this area, wind gusts will range from 20 to 30 mph with the strongest gusts out across parts of the Arco Desert. There is a very small chance (10 to 15 percent) for an isolated shower or storm in parts of the South Hills and up north along the Idaho/Montana divide as a bit of moisture does its best to work up and around the high pressure over our area. Expect Sunday to be a nearly identical weather day. The ridge of high pressure gets flattened a bit early next week as an area of low pressure moves into British Columbia and troughing extends southward into the Pacific Northwest. Where that low will track throughout the rest of the week is not exactly resolved yet by the longer range models, but afternoon highs will slowly decrease during the week, falling to the low to mid 80s by next Friday. Isolated shower and storm chances will be around through next week, but it may not be until the end of the week/next weekend that we finally see some potential for more widespread precipitation.

AVIATION /12Z TAFS THROUGH 12Z SUNDAY/

Issued at 540 AM MDT Sat Aug 8 2026

While high pressure still is steering our forecast, there is a slight increase in moisture today, leading to more mid and upper level clouds. This increasing moisture also brings a very small (10 to 15 percent) chance for an isolated shower or storm today, mainly in the southern portion of the area. As such, have left the VCSH in at BYI. Wildfire smoke also remains in Eastern Idaho today with usual TEMPO groups to decrease VIS to around 4 or 5SM at times today. Winds gusts are on the uptick today, so look for gusts to around 20kts this afternoon at PIH, IDA, and SUN.

FIRE WEATHER

Issued at 209 AM MDT Sat Aug 8 2026

A RED FLAG WARNING is in effect for the Central Mountains (Fire Weather Zones 475 and 476) later today from 1 PM to 9 PM MDT due to gusty winds and critically low min RHs. Within this area, min RHs will fall to single digits in some spots, but generally remain in the 10 to 15 percent range this afternoon. Expect wind gusts of 20 to 25 mph. Outside of the Central Mountains we will see near-critial fire weather conditions with gusts of 20 to 30 mph and min RHs of 10 to 20 percent. A very small chance (10 to 15 percent) of an isolated shower or storm will exist today in the South Hills and Island Park area as just a bit of moisture tries to work its way up and over the ridge of high pressure. There will be little change in the forecast for Sunday as that high pressure remains in control of the pattern. Things begin to change throughout next week, but it will be a slow change. Troughing begins to move into the Pacific Northwest early next week thanks to an area of low pressure moving into British Columbia. This will drop afternoon highs by just a couple of degrees each day as wind gusts stay in the 20 to 30 mph range. While there will be some isolated shower/storm chances during the afternoons in the first half of next week, we may have to wait until the end of next week before we see the chance for more widespread precipitation to increase.

AIR QUALITY

Issued at 209 AM MDT Sat Aug 8 2026

An Air Quality Advisory remains in effect for Custer County through Monday afternoon due to air quality expected to remain in the "moderate" to "unhealthy for sensitive groups" categories.

PIH WATCHES/WARNINGS/ADVISORIES

Heat Advisory until 11 PM MDT this evening for IDZ051>059-062. Air Quality Alert until 3 PM MDT Monday for IDZ068>074. Red Flag Warning from 1 PM this afternoon to 9 PM MDT this evening for IDZ475-476.