A vigorous, but dry, cold front swept south across northeast California and the Sierra Nevada on the 8th. 10 inches of liquid-equivalent precipitation.
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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.
A vigorous, but dry, cold front swept south across northeast California and the Sierra Nevada on the 8th. Most locations did not receive any precipitation with this front, but a few favored upslope areas in the Sierra did record up to about 0.10 inches of liquid-equivalent precipitation. The more impressive weather associated with the front was very strong east winds at the ridge tops in the wake of the frontal passage. Many mountain sites saw peak gusts well in excess of 100 mph.
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 Feb 7, 3:00 PM PST, 11 hours 45 minutes earlier.
Area Forecast Discussion
National Weather Service Reno NV
300 PM PST Fri Feb 7 2020
.SYNOPSIS...
The warm and dry trend will continue through Saturday before a
strong cold front sweeps through the region. The cold front will
bring gusty winds, light snow and rapid drop in temperatures by
Sunday. Breezy north to easterly winds are possible Saturday night
into Monday with much stronger gusts for the Sierra.
&&
.SHORT TERM...
**Changes: Updated wind forecast for this weekend. Issued Wind
Advisories for the Lake Tahoe Basin, as well as Alpine, and Mono
Counties, for Sunday and Sunday night due to the strong east
wind event. Lake wind advisories were also issued for Lake Tahoe
and Pyramid Lake for potentially hazardous boating conditions
Saturday afternoon ahead of the front, all the way through early
Monday morning.
It's a beautiful day out there! Temperatures in western Nevada
have climbed all the way into the low 60s this afternoon. Very
dry conditions will continue through tomorrow, allowing for
temperatures tonight to cool off sharply along with a return of
valley inversions.
A sharp, but mostly dry area of low pressure will move through
the Pacific Northwest and into northern CA/NV Saturday through
Sunday, increasing winds across the region and bringing a chance
for light snow in the Sierra. As southwest winds increase Saturday
ahead of the front, this will also increase mixing and push
temperatures back up to the 60s once again for western Nevada (50s
in the Sierra). Both Tahoe and Pyramid lakes will become choppy
by Saturday afternoon due to the gusty winds ahead of and along
the front. The front will pass through the region during the day
on Saturday, with winds becoming northerly behind the front by
Saturday afternoon into Saturday evening. Blowing dust will also
be a potential for Saturday in west-central Nevada, especially
around Fallon and Hawthorne.
By late Saturday night into Sunday morning, we will see some
light snow accumulations in the Sierra, especially from Tahoe
south into Mono County. Up to an inch may be possible for the
higher elevations and Sierra passes. Much colder conditions are
expected Sunday behind the front, along with abundant cloud cover
banking up along the Sierra.
The biggest impact for our region is expected to be the strong
east winds that will develop on Sunday and Sunday night behind the
cold front. Although east winds are not unusual for our region,
but the strength of these east winds IS unusual. We have issued a
wind advisory for Sunday and Sunday night for the potential of
some isolated damaging winds from this northeasterly direction.
Northeast winds are notorious for tree damage in the Sierra, as
the predominant wind direction is southwest and tree root systems
are weaker against northeast winds. That being said, gusts up to
100-120 mph along the Sierra Crest will be common Sunday night,
including Tahoe and Mammoth Mountain. Below the ridgelines, strong
winds are possible up to 40-60 mph.
Strong NE winds may result in ski area impacts, tree damage and
powerline damage. Some minor lake shore flooding may be possible
on the western shores of Tahoe as well, due to the high lake level
and high surf. Light snow will also continue in Mono and Alpine
Counties on Sunday due to the upslope east flow, allowing for
potentially another inch or two of light accumulation.
Winds will gradually diminish into Monday afternoon, with
clearing skies and temperatures warming back up to near average
for this time of year. -Hoon
.LONG TERM...Tuesday through Friday...
The large scale pattern in the extended forecast remains in a
blocked pattern with amplified ridging positioned across the eastern
Pacific. This will result in temperatures warming above season
averages and could set the stage for valley inversions through
Wednesday with poor ventilation early each day. Winds and valley
mixing should improve some by Thursday as an inland trough drops in
from the Pacific Northwest.
This trough will provide our only potential for precipitation next
week around the Friday timeframe. However due to its inland
trajectory and fast motion, precipitation amounts look pretty
limited with roughly about a 30% probability of seeing around at
least 0.10" of precipitation. Cooler and more seasonable
temperatures do look more likely for next weekend after the trough
passage. At this time, no promising indicators of the large scale
ridging breaking down, so could remain in pattern favoring above
average temperatures with below average precipitation through
February. Fuentes
&&
.AVIATION...
VFR conditions will prevail through Saturday, but an approaching
cold front will increase winds beginning Saturday morning. Gusty west
winds will ramp up ahead of the front along with mountain wave
turbulence and local LLWS possible as surface gusts reach to 35 kts.
Behind the front, isolated MVFR with -SHSN mainly Sunday focused on
the Sierra terminals with only trace amounts of snowfall expected
with up to 0.5" of accumulation on the high end. Gusty NE winds will
also prevail with 30-35 kts gusts possible for valleys and terminals
across western Nevada and around 40 knots for KTRK, KTVL, KMMH.
Ridge gusts will exceed 100 kts Saturday afternoon and evening. LLWS
likely in the Sierra, along with significant mountain wave
turbulence especially along and west of the Sierra. Fuentes
&&
.REV Watches/Warnings/Advisories...
NV...Lake Wind Advisory from 10 AM Saturday to 10 PM PST Sunday for
Pyramid Lake in NVZ004.
Wind Advisory from 10 AM Sunday to 4 AM PST Monday NVZ002.
Lake Wind Advisory from 10 AM Saturday to 10 AM PST Sunday for
Lake Tahoe in NVZ002.
CA...Wind Advisory from 10 AM Sunday to 4 AM PST Monday CAZ072-073.
Lake Wind Advisory from 10 AM Saturday to 10 AM PST Sunday for
Lake Tahoe in CAZ072.
&&
For more information from the National Weather Service visit...
http://weather.gov/renoThe national radar mosaic for the moment the first event began.
10 high wind. Local standard time, as filed.
Mesonet CEDC at Cedarville (elevation 4600 feet MSL) recorded a 59 mph wind gust.
Mesonet SUMAM on Ward Peak measured a wind gust of 66 mph (elevation 8483 feet MSL).
Mesonet MTH02 Mammoth Chair 22 measured a 62 mph wind gust (elevation 10067 feet MSL).
Mesonet MTH03 Mammoth Summit measured a 69 mph wind gust (elevation 11053 feet MSL).
Mesonet Buoy JPL02 4 miles west of Glenbrook on Lake Tahoe (elevation 6233 feet MSL) recorded a 58 mph wind gust.
Mesonet SUMAM on Ward Peak measured a wind gust of 125 mph (elevation 8483 feet MSL). Sustained winds were well over 70 mph the 3 hours previous and after the time of the maximum gust. Several wind gusts were over 100 mph in that period as well.
Mesonet FW4812 at Echo Lake measured a wind gust of 73 mph (elevation 7434 feet MSL). Several wind gusts in the previous 3 hours were over 58 mph.
Mesonet SIBSV Siberia atop Squaw Summit measured a wind gust of 90 mph (elevation 8700 feet MSL). Several gusts in the previous 3 hours were well over 60 mph.
Mesonet MTH02 Mammoth Chair 22 measured a 108 mph wind gust (elevation 10067 feet MSL). Sustained winds were from the northeast and periodically over 70 mph the 3 hours after the time of the maximum gust. Several wind gusts were over 100 mph in that period as well.
Mesonet MTH03 Mammoth Summit measured a 130 mph sustained wind coinciding with a 145 mph wind gust (elevation 11053 feet MSL). Sustained winds were from the northeast and were periodically over 100 mph the 3 hours before the time of the maximum gust. Several wind gusts were over 110 mph in that period as well.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2020Every state in 2020This day in weather historyWarnings in California, February 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: 906370, 907303, 907307, 907304, 907912, 907901, 907902, 907900, 907904, 907906.