textproduct: Pocatello

KEY MESSAGES

- Isolated to scattered thunderstorms this afternoon. Gusty outflow winds possible near storms.

- Threat for showers and thunderstorms increases Thursday through Saturday.

- Locally heavy rain possible with burn scars most vulnerable.

DISCUSSION

Issued at 108 AM MDT Thu Aug 13 2026

Forecast remains mostly consistent. We have southwest flow over our area with a longwave trough set up over the west coast. A strong circulation over central California will break up today. A large chunk of that circulation will eject towards our region today. As it moves towards our area, it will interact with the monsoon moisture and produce widespread showers with isolated to scattered thunderstorms. The track of the low has consistently been through the Magic Valley. As a result, the Magic Valley may see more showers and less thunderstorm activity. Along the edges of that track, scattered storms look likely. Eastern Idaho, especially the eastern highlands has been consistently favored for heavier rainfall amounts from storms with up to 0.50 inches possible this afternoon. Convection and qpf amounts across the central mountains is a bit of a question mark with how much the mid and upper level clouds from the low suppress development. A flash flood watch remains in effect for the Big Rock Fire east of Idaho Falls where combination of steep terrain, the effects of the recent burn, and the potential for heavy rain exist. Most of the activity will move into Montana this evening, but a few isolated showers may persist through the night.

On Friday, a second impulse arrives from the southwest. This second system isn't nearly as strong. As a result, coverage isn't as widespread. Models are favoring the mountains and highlands for the best chances for activity on Friday, especially the central mountains which are closer to the storm track. Locally heavy rainfall will remain a threat as the monsoonal moisture isn't going anywhere.

On Saturday, one final impulse works through the region. The best chances for storms is across the central mountains as the flow begins to flatten from southwesterly to westerly. Isolated to scattered showers and thunderstorms will remain possible areawide largely due to the monsoon moisture. Potentially, could see a limited flash flood threat once again Saturday. But the convection is beginning to shift from organized (good idea of where convection will be) to disorganized (random).

The forecast for Sunday into early next week looks largely dry. But, the moisture is still in place. Dew points will still be sitting in the mid 40s to low 50s across the region, which is high for our area. Think at least isolated heat of the day pop up storms will be around. The cap associated with the ridge is rarely strong enough to completely suppress convection when the moisture is as high as it is.

Daytime highs look well below normal for the remainder of the week and will not approach normal until early to mid next week.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 108 AM MDT Thu Aug 13 2026

Main issues are once again thunderstorm potential. Will include a prob30 this afternoon for gusty outflow winds. Otherwise, expect showers around most areas this afternoon. The threat for isolated to scattered storms will persist into the weekend. Locally heavy rain may accompany these storms.

FIRE WEATHER

Issued at 108 AM MDT Thu Aug 13 2026

Red flag warnings remain in place across the region for scattered thunderstorms and gusty outflow winds today. Locally heavy rain is possible with storms, especially across east Idaho this afternoon.

PIH WATCHES/WARNINGS/ADVISORIES

Red Flag Warning from noon today to 9 PM MDT this evening for IDZ410-411-413-422-425-427-475-476.