2 degrees above the monthly normal.
Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS PIH wrote it up.
It was the hottest June ever recorded at Challis with an average monthly temperature of 70.1 degrees which was 9.2 degrees above the monthly normal.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Pocatello, ID wrote its last area forecast discussion before the first event at May 31, 1:12 PM MST, 10 hours 49 minutes earlier.
Area Forecast Discussion National Weather Service Pocatello ID 212 PM MDT Mon May 31 2021 .SHORT TERM...Tonight through Wednesday night. Upper ridge continues to build across the region. Satellite and radar imagery shows weak convective development across the higher terrain. So far there is no lightning per observations, but allowed for isolated thunder. Believe thunder will dissipate before or around sunset. Rest of the forecast should remain dry with temperatures continuing to warm well above normal, leading to hot temperatures toward the end of the week. DMH .LONG TERM...Thursday through Monday. Big impact in the long term will be the heat on both Thursday and Friday as high temperatures are expected to reach well into the 90s in the Snake River Plain. May see isolated thunderstorms Friday in the central mountains and Upper snake River Highlands. A weak system and moving of upper ridge to east will allow for some cool down Saturday with highs back into the 80s in low elevations. A cooler pattern looks to be settling in with temperatures likely to drop again Sunday into Monday but still above normal and the chance of mainly mountain showers and thunderstorms as well. GK && .AVIATION... VFR conditions will continue through Tuesday with only high cloud cover expected with some mid level cumulus. Winds are expected to be 10 knots or less for the most part in the afternoons through Tuesday as well. GK && .PIH WATCHES/WARNINGS/ADVISORIES... None. &&
The national radar mosaic for the moment the first event began.
1 excessive heat. Local standard time, as filed.
It was the hottest June ever recorded at Challis with an average monthly temperature of 70.1 degrees which was 9.2 degrees above the monthly normal.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Idaho in 2021Every state in 2021This day in weather historyWarnings in Idaho, June 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 965376.