Deep low pressure moving in from the Pacific Northwest brought strong to high winds over much of southeast California.
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 VEF wrote it up.
Deep low pressure moving in from the Pacific Northwest brought strong to high winds over much of southeast California.
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 Las Vegas, NV wrote its last area forecast discussion before the first event at May 20, 1:38 PM PST, 2 hours 17 minutes earlier.
Area Forecast Discussion National Weather Service Las Vegas NV 238 PM PDT Thu May 20 2021 .SYNOPSIS... A low pressure system dropping down continues to produce strong winds across the region this afternoon. The system will bring considerably cooler temperatures by Friday with scattered showers across the southern Sierra and south central Nevada with light snow accumulations possible above 6000 feet. Winds diminish Saturday and Sunday, though temperatures will remain below normal as the system slowly lifts away to the north. && .SHORT TERM...Today through Friday Night... A large low pressure system continues its southward transit from the Pacific Northwest into northern California. Strong south to southwest winds have developed ahead of the system across much of the area. A High Wind Warning remains in effect for northwest San Bernardino County through this evening as well as a Wind Advisory for most of the rest of the area. Winds have been gusting 45-50 mph in many areas with locally higher gusts. The low pressure system will slow down and remain mostly stationary across central NV on Friday. The associated cold front will slow down and likely not reach the Las Vegas Valley so a turn to northerly wind is not expected except across central Nye, Esmeralda and northern Inyo counties. Winds will decrease west to east overnight with windy conditions continuing in northwest Arizona Friday. Increasing clouds and a chance for precipitation begin in the wake of the front. Accumulating snow can be expected above 6kft in the Eastern Sierra with totals of a few inches up to 8 inches or so at the peaks. A little snow is also possible at the highest elevations of the southern NV mountains. Temperatures Friday will be quite cool under the influence of the colder airmass with highs in most areas 15-20 degrees below normal. .LONG TERM...Saturday through Wednesday... A slow warmup begins Saturday with warming each day through mid week with seasonally normal temperatures by Monday and a few degrees warning by Wednesday. Another storm system will move south out of the Pacific Northwest mid-week but at this time it looks to be less potent than our current system. There is also s high level of uncertainty in its track and timing. When it does arrive, we will likely have breezy conditions and an increase in clouds. && .FIRE WEATHER... Strong winds gusting 40-55 mph will be common through late this evening across the area as a low pressure system affects the area. Rain and high elevation snow can be expected across the eastern Sierra on Friday and northern portions of the Owens Valley. More sparse areas of precipitation are possible across northern Inyo, central Nye, and Esmeralda counties as well as the higher elevations of southern NV. The focus shifts to NW AZ Friday as Red Flag conditions will remain for Arizona Zone 102. && .AVIATION...For McCarran... Gusty southwest winds are expected remain through the early evening today with gusts to around 30-40 knots. Strongest winds are expected to decrease around 06-07Z tonight, but there is moderate confidence that southwest gusts to around 20-25 knots may continue overnight. Less gusty southwest winds are expected Friday, with gusts to around 25 knots. Mostly clear skies are expected through the forecast period. Due to strong winds, expect turbulence through much of the forecast period. For the rest of southern Nevada, northwest Arizona and southeast California... Widespread gusty west to southwest winds are expected to continue through this afternoon, with gusts to 30-40 knots. However, northwest winds are expected at KBIH. Stronger winds are expected at KDAG, where gusts over 50 knots will be possible through this afternoon. Strongest winds are expected to decrease overnight, but are expected to remain breezy with gusts to 15-25 knots at most TAF sites. Less gusty winds are expected Friday, with gusts to 25-35 knots and winds are expected to decrease by late afternoon/early evening Friday. With strong winds today, expect turbulence and possible low-level wind shear, especially in the lee slopes of north- south oriented mountain ranges. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && DISCUSSION/FIRE WEATHER...Berc AVIATION...Peters For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter
The national radar mosaic for the moment the first event began.
2 high wind. Local standard time, as filed.
This gust was measured at the Barstow-Daggett Airport (KDAG) ASOS.
The peak gust was measured 22 miles SSE of Olancha. A big rig was blown over on Highway 395.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2021Every state in 2021This day in weather historyWarnings in California, May 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: 952116, 952117.