A large, cold, and slow moving system over the West brought a modest snowfall to the Sierra on the 15th.
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 REV wrote it up.
A large, cold, and slow moving system over the West brought a modest snowfall to the Sierra on the 15th.
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 Reno, NV wrote its last area forecast discussion before the first event at May 14, 9:48 PM PST, 3 hours 12 minutes earlier.
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</html>The national radar mosaic for the moment the first event began.
1 winter weather. Local standard time, as filed.
Four to seven inches of snow fell from South Lake Tahoe north and west to the Sierra crest near Donner Summit. The morning snow and cold as well as wet roads later in the day forced the delay and eventual cancellation of the first leg of the Amgen Pro Cycling Tour.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2011Every state in 2011This day in weather historyWarnings in California, May 2011
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 2026-09-30. Each event’s entry at NCEI: 312658.