Late season storm brought sharply colder temperatures, stronger winds, and periods of valley rain and mountain snow to the Sierra and Western Nevada.
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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.
Late season storm brought sharply colder temperatures, stronger winds, and periods of valley rain and mountain snow to the Sierra and Western Nevada.
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 Apr 23, 1:27 PM PST, 10 hours 33 minutes earlier.
Area Forecast Discussion
National Weather Service Reno NV
227 PM PDT Fri Apr 23 2021
.SYNOPSIS...
Late season winter storm will impact the region Saturday with
cooler temperatures, elevated winds, blowing dust and some light
mountain showers. Precipitation will increase Saturday night with
periods of rain, snow and hazardous driving conditions in the
Sierra through Sunday. Some rain and snow is also possible for
western Nevada. Warmer weather and dry conditions return on
Tuesday.
&&
.SHORT TERM...
The Highlights...
* Late season winter storm remains on track for Saturday-Sunday
* Saturday: Windy, cooler, blowing dust, and light mountain
showers.
* Sunday: Periods of rain/snow with embedded bursts of heavier
snow, 10-20% chance of thunderstorms, and gusty winds.
Timing of the system and impacts hasn't changed, though track of
the cold core with the low could lead to some rather low snow
levels for late April in some locations Sunday morning.
Winds: No big changes here. Some mountain waves will develop with
the jet stream overhead Saturday, but strong/damaging downslope
potential appears rather low (10-20%) along US-395 and US-95.
Its late April and the southern half of NV will be in the mid-
upper 80s, allowing strong surface gradients to drive the strength
of the winds. Expect periods of 20-30 mph sustained winds with
gusts 40-50 mph Saturday afternoon. A few wind prone locations may
push into the 50-60 mph range. This raised a concern for larger
dust plumes from the Smoke Creek, Black Rock, Carson Sink, and
many smaller dust sources across eastern Sierra and western NV.
Visibility could drop below 1 mile at times for those traveling
along I-80/US-50/US-95 tomorrow. Winds may diminish a bit
overnight, but will remain breezy. Winds Sunday should be lighter,
but may still gust 30-45 mph with a cold front moving through the
region.
Rain/Snow: Latest simulations start the heavier snow in the
northern Sierra/Tahoe Basin Saturday night or early Sunday AM with
activity diminishing Sunday night. Leaning on two periods of
heavier rain/snow with potentially low snow levels (4000-5000 ft)
in the Sierra. One with the frontal boundary Sunday morning and a
second with heavier showers/isolated thunderstorms developing in
the cold/unstable air behind the front Sunday afternoon/early
evening. Have also extended the threat area for decent snow
accumulations beyond the Tahoe Basin. Expecting at least 4-8
inches (20-30% chance of exceeding 12 inches) along the Sierra
Crest from Plumas County, Tahoe Basin, southward to about Tioga
Pass. Mammoth may receive heavy snow accumulations as well. In the
Sierra below 7000 feet, general amounts should remain at less
than 4 inches, unless a heavier burst of snow lingers over one
location. For western NV, minimal threat for accumulating snow
expect for the Virginia Highlands, and some foothill locations
above 5000 ft where an inch or two is possible Sunday AM when the
snow levels may dip below 5000 ft.
A final note on this system. Its late April, accumulations and
snow levels may be highly variable depending on the track of the
cold unstable air and where heavier snow showers develop. Be
prepared for snow as low as 4000-5000 feet Sunday AM, but also
expect the snow to melt off roads below 8000 ft during the day
Sunday with the late April sun angle. Brong
.LONG TERM...
The late-season storm will move out of the region Monday into
Tuesday, with lingering rain and snow showers for the Sierra and
western Nevada. Temperatures Monday will be rather cool, with 50s
for western Nevada valleys and 30s to 40s in the Sierra. We look to
begin a warm-up Tuesday through Friday. Ensemble guidance continues
to show an adequate signal for a ridge building over the western US
mid-to-late next week. Depending on how strong this ridge amplifies,
we could reach back to around 80 here in western Nevada by the end
of the week depending on how strong this ridge amplifies. Typical
afternoon breezes should return Wednesday-Friday next week. -Johnston
&&
.AVIATION...
VFR conditions through the remainder of the day with some westerly
breezes.
A late-season storm moves into the Sierra and western Nevada
Saturday, bringing gusty winds along with rain and mountain snow.
Winds will begin to increase tonight across the Sierra and into
western Nevada by daybreak Saturday. Increased turbulence and LLWS
are expected from tonight through Monday morning for the region.
As the main wave moves inland Saturday night into early Monday,
periods of moderate to heavy snowfall will be possible at
KTVL/KTRK/KMMH, with the poorest conditions Saturday night through
late Sunday. Lighter valley spillover rainfall is expected for the
main terminals of western Nevada late Saturday night through early
Monday morning. -Johnston
&&
.REV Watches/Warnings/Advisories...
NV...Lake Wind Advisory from 5 AM Saturday to 3 AM PDT Sunday NVZ002.
Winter Weather Advisory from 3 AM Sunday to 5 AM PDT Monday
NVZ002.
Wind Advisory from 11 AM to 11 PM PDT Saturday NVZ001-004.
Wind Advisory from 8 AM to 11 PM PDT Saturday NVZ003-005.
CA...Lake Wind Advisory from 5 AM Saturday to 3 AM PDT Sunday CAZ072.
Winter Weather Advisory from 3 AM Sunday to 5 AM PDT Monday
CAZ072.
Winter Weather Advisory from 11 PM Saturday to 11 PM PDT Sunday
CAZ071.
Wind Advisory from 8 AM to 11 PM PDT Saturday CAZ070-071.
Winter Weather Advisory from 3 AM Sunday to 5 AM PDT Monday
CAZ073.
Wind Advisory from 5 AM to 11 PM PDT Saturday CAZ073.
&&
For more information from the National Weather Service visit...
http://weather.gov/renoThe national radar mosaic for the moment the first event began.
2 winter weather, 1 high wind. Local standard time, as filed.
Widespread wind gusts over 60 MPH impacted the Eastern Sierra with gusts over 80 MPH along the Sierra Crest. Highest gust near a community was 70 MPH near Lee Vining.
Lake Davis received 6-7 inches new snowfall.
Tahoe and Truckee areas generally receiving 1-3 inches snowfall with 6 inches at Olympic Valley Ski.
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, April 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: 952195, 952198, 952199.