Severe thunderstorms developed across parts of South Central Idaho and the West Central Mountains ahead of a strong cold front.
Every event with a place to put it. 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 BOI wrote it up.
Severe thunderstorms developed across parts of South Central Idaho and the West Central Mountains ahead of a strong cold front.
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 Boise, ID wrote its last area forecast discussion before the first event at May 30, 12:53 PM MST, 3 hours 7 minutes earlier.
Area Forecast Discussion National Weather Service Boise ID 153 PM MDT Sat May 30 2020 .SHORT TERM...Tonight through Monday night...Forecast was updated to include a Severe Thunderstorm Watch for Harney County this afternoon through early this evening. Harney County will be on the eastern edge of an upper low which will be the focus for the threat of severe thunderstorms as the low moves through central Oregon. Any thunderstorms that develop in Harney County will have the potential for large hail and damaging wind. Elsewhere, there is still a threat of strong winds and hail with the isolated thunderstorms that are expected across portions of southeast Oregon and southwest Idaho through tonight. Winds have been increasing throughout the region this afternoon, with a few observations reaching gusts exceeding wind advisory levels of 45 mph near the Nevada border. The stronger winds will expand into Harney, Malheur, and Owyhee counties this afternoon. The cold front will move through the area this evening, accompanied by gusty winds. A dry and stable southwest flow aloft will follow the exiting low and cold front on Sunday, resulting in mostly clear skies, light winds, and cooler temperatures (near normal). A weak upper trough will be accompanied by a chance of showers and a slight chance of afternoon-evening thunderstorms on Monday as it moves through the Pacific Northwest. The convection will favor the north portions of the forecast area (mainly Baker County and the West Central Mountains). Temperatures will remain close to normal and winds will be mainly light. .LONG TERM...Tuesday through Saturday...Models are trending drier through the middle of the week as a ridge builds over the Great Basin and a closed low sits off the California coast. By Thursday, upper level flow will turn southwesterly, though models continue to disagree over moisture levels. A few showers and thunderstorms are expected to initiate over higher elevations Thursday and Friday. A system will drop along the Canada coast and into the Pacific Northwest next weekend, ushering in breezy conditions with widespread precipitation and a chance of afternoon thunderstorms. Temperatures through the extended will stay 5-10 degrees above normal, then return to near-normal Saturday with the approaching system. && .AVIATION...VFR. Windy conditions across SE Oregon and along the Idaho/Nevada Border. Scattered showers and thunderstorms will develop over higher terrain this afternoon and evening. Surface winds: mostly SE 20-30 kts ahead of and near a cold front. Gusts of 45-50 kts possible, especially across SE Oregon. Storms will also produce localized gusty winds and may produce hail. Winds aloft near 10k ft MSL: S 25-45 kts, turning SW behind the cold front. Sunday Outlook...VFR with weak mountain showers possible in the evening. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...Wind Advisory until midnight MDT tonight IDZ015-029. OR...Wind Advisory until midnight MDT /11 PM PDT/ tonight ORZ061-063. && www.weather.gov/Boise www.facebook.com/NWSBoise www.twitter.com/NWSBoise SHORT TERM...BW LONG TERM....AL AVIATION.....AL
Special Weather Statement
National Weather Service Boise ID
357 PM PDT Sat May 30 2020
ORZ062-302345-
Baker County OR-
357 PM PDT Sat May 30 2020
...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN BAKER COUNTY UNTIL
445 PM PDT...
At 356 PM PDT, Doppler radar was tracking a strong thunderstorm near
McEwen, or 10 miles west of Baker City, moving north at 40 mph.
Half inch hail and wind gusts up to 40 mph will be possible with this
storm.
This strong thunderstorm will be near...
Elkhorn Peak around 400 PM PDT.
Haines around 410 PM PDT.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
When safe to do so, please relay storm reports to the National
Weather Service in Boise via local law enforcement, or National
Weather Service Boise Facebook and Twitter accounts.
&&
LAT...LON 4467 11791 4467 11816 4502 11819 4502 11816
4505 11813 4505 11811 4500 11801 4500 11796
4506 11787
TIME...MOT...LOC 2256Z 180DEG 36KT 4475 11804The Boise radar (KCBX), 59 km away, was scanning. The volume nearest the first event began at 23:00 UTC.
8 thunderstorm wind. Local standard time, as filed.
A resident in Homedale reported metal roofing bent and and portions ripped off, and downed trees.
A 12 foot diameter Poplar tree was uprooted in Gooding.
Damage was widespread across the valley including downed trees of various sizes.
Damage was widespread throughout the valley including downed trees and fences.
A tree was blown over onto a cabin in Garden Valley and downed trees and power lines closed a section of Highway 55 near the Banks to Lowman Road.
Downed trees and power lines blocked old Highway 95 near Hot Springs Road.
Downed trees blocked Warren Wagon Road.
The ITD21 weather station at mile post 190 on I-84 recorded a wind gust of 77 MPH.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Idaho in 2020Every state in 2020This day in weather historyWarnings in Idaho, May 2020
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: 895438, 895439, 895436, 895433, 895441, 895444, 895442, 895440.