textproduct: Pocatello

KEY MESSAGES

- Heat risk highest today, especially across the Magic Valley, Snake River Plain, and South Hills. Many low elevations will warm to around 100 degrees.

- Monsoon moisture increases beginning this evening. More widespread storms later evening through mid-week.

DISCUSSION

Issued at 414 AM MDT Mon Jul 20 2026

Heat risk is at its peak today with HEAT ADVISORIES in effect for much of Southeast Idaho from Noon today through 8 PM MDT this evening for temperatures near or up to 100 degrees. Temperatures will gradually cool through mid-week back to around normal to slightly below normal.

Southwest flow will lift monsoonal moisture into Southeast Idaho beginning this evening and will support daily shower and thunderstorm chances through mid to late week. Isolated storms will trend more scattered heading later into the week with locally heavy rainfall and outflow winds of 40 to 50 mph. High resolution models show activity primarily concentrated across central and south- central Idaho during the evening with development further east during the late night and overnight hours.

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 542 AM MDT Mon Jul 20 2026

Very little additions made to the forecast this TAF issuance. Have kept VCSH at all sites beginning at 03z with no transition to showers due to the dry nature of thunderstorms today. Otherwise, expect increasing mid- to high- level clouds and outflow winds ranging 40 to 50 mph.

FIRE WEATHER

Issued at 414 AM MDT Mon Jul 20 2026

Excessive heat peaks today with many valley locations warming to around 100 degrees, although heating could be inhibited in areas where extensive cloud cover develops. Monsoonal moisture will support daily shower and thunderstorm chances through mid to late week. Isolated, mostly dry storms today will trend wetter and more scattered heading later into the week with locally heavy rainfall possible and outflow winds of 40 to 50 mph. High resolution models show activity primarily concentrated across Fire Weather Zones 475 and 476 this evening with development further east across 410 and 413 during the late night and overnight hours. Widespread Min RH today will range 13 to 16 percent across Fire Weather Zones 410 and 425, but Min RH will raise to 25 percent and higher beginning Tuesday as monsoonal moisture lifts northward.

PIH WATCHES/WARNINGS/ADVISORIES

Heat Advisory from noon today to 8 PM MDT this evening for IDZ051>059.