An unseasonably cold low pressure system brought heavy snow to locations above five-thousand feet across Clearwater and Lemhi counties. Several SNOTEL stations reported their all-time highest, twenty-four hour precipitation totals, over two inches for anytime of the year in Lemhi County, going back to the early 1980s.
Every event with a place to put it; 2 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 MSO wrote it up.
An unseasonably cold low pressure system brought heavy snow to locations above five-thousand feet across Clearwater and Lemhi counties. Several SNOTEL stations reported their all-time highest, twenty-four hour precipitation totals, over two inches for anytime of the year in Lemhi County, going back to the early 1980s.
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 Missoula, MT wrote its last area forecast discussion before the first event at Jun 16, 1:29 PM MST, 10 hours 31 minutes earlier.
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</html>The national radar mosaic for the moment the first event began.
2 heavy snow. Local standard time, as filed.
Up to two feet of snow fell near Williams Creek Summit, which caused numerous trees to break or fall over the road, making travel impossible for much of the day. Approximately 14 inches of wet snow fell at Lost Trail Pass adversely impacting travel.
The Darkhorse Lake SNOTEL reported 19 inches of total snowfall with this event, while 9 inches fell at Schwartz Lake. The Schwartz Lake SNOTEL reported a 24 hour precipitation total of 1.80 inches which is the highest amount reported for any time of the year, going back to 1995. Gilmore Summit saw heavy snow that covered the road with several inches of slush.
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, June 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 2026-10-01. Each event’s entry at NCEI: 895210, 895578.