textproduct: Pocatello

KEY MESSAGES

- Burn Scar Flash Flood Risk: Deep monsoonal moisture across Eastern Idaho will support localized heavy rainfall and flash flooding today and Saturday. Flash Flood Watches remain active for the Wapiti and Big Rock burn scars today, with the Wapiti watch extending through Saturday.

- Active Saturday Storm System: Remnants of a West Coast upper- level trough will track through the region on Saturday, generating widespread showers and thunderstorms once again.

- Gradual Warm-Up and Mid-Week Drying: Unseasonably cool temperatures (highs in the 70s) will slowly moderate into early next week. A passing northern disturbance will keep storm chances elevated over the northern high country Monday and Tuesday before drier, seasonal conditions settle in mid- to-late week.

DISCUSSION

Issued at 159 PM MDT Fri Aug 14 2026

Afternoon satellite imagery reveals partial clearing across the region today, which has allowed surface temperatures to recover slightly into the 70s across lower elevations. This solar heating, combined with an entrenched plume of deep monsoonal moisture, has initiated another round of showers and isolated thunderstorms. While convective coverage will remain highest across the Central Mountains and Eastern Highlands, scattered showers and storms will also track across the Snake Plain into the evening hours. High precipitable water values will make the strongest cells capable of localized flash flooding, with recent burn scars facing the highest vulnerability. A Flash Flood Watch remains in effect for both the Wapiti and Big Rock burn scars through this evening with the former location continuing into the evening tomorrow. Convective activity is forecast to diminish overnight before ramping back up toward daybreak Saturday.

Atmospheric conditions will remain active on Saturday as the remnant shortwave of a West Coast trough lifts northeastward across Idaho. Model guidance continues to highlight the Central Mountains for the most concentrated shower and thunderstorm activity. Convective coverage elsewhere will be more scattered as the upper-level flow transitions from southwesterly to westerly, keeping the primary forcing mechanism aligned closer to the northern terrain. Because deep moisture remains locked in place over the Central Mountains, the threat of heavy rainfall over the Wapiti burn scar remains high enough to maintain the Flash Flood Watch on Saturday. Confidence in organized thunderstorm coverage directly impacting the Big Rock scar is lower at this time.

A transitional pattern begins Sunday as the primary monsoonal moisture plume shifts eastward, offering a mostly dry finish to the weekend for much of Eastern Idaho outside of isolated to scattered central mountain showers and storms. Early next week, a weak shortwave passing to our north on Monday and Tuesday will maintain elevated precipitation chances from the Central Mountains through the Island Park area, while locations further south see only isolated coverage. Behind this wave, drier air will build into the Intermountain West for the mid-to-late week timeframe, suppressing widespread shower activity. Daytime temperatures currently running well below seasonal averages due to cloud cover and rain will steadily moderate through early next week, returning close to normal levels by late next week as the drier weather takes hold.

AVIATION /18Z TAFS THROUGH 18Z SATURDAY/

Issued at 1106 AM MDT Fri Aug 14 2026

Have prob30 thunderstorms at all sites today through 02Z. Have a tempo 18Z through 20Z at DIJ as an area of storms look to hit them between noon and 1 pm. But the threat remains all afternoon and early evening with any storm producing 30 to 45 knot wind gusts. Some drying overnight with showers hanging around with some vicinity in all the TAFs. Winds not strong outside of thunderstorms mainly under 10 knots. Threat for showers and storms remains Saturday.

FIRE WEATHER

Issued at 119 PM MDT Fri Aug 14 2026

The threat for showers and thunderstorms will continue this afternoon and evening and continue Saturday as well. All thunderstorms will be wet with the potential for wetting rains under stronger thunderstorms. Potential wind gusts over 30 mph as well near any outflow. Coverage decreases Sunday and expect some drying next week as an upper level ridge tries to build in once again. The driest conditions expected to be next week Wednesday through Friday. At least isolated showers and thunderstorms continue through Tuesday. Temperatures again rise to warmer than normal by late next week as well after the recent cooler conditions which will exist through the weekend into early next week.

PIH WATCHES/WARNINGS/ADVISORIES