A strong upper level low over the northeast Pacific on February 28th moved southeast, reaching southern Oregon/northern California on the 1st of March. This system brought high winds and snowfall to the Sierra Nevada and western Nevada through the 3rd.
Every event with a place to put it; 16 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 strong upper level low over the northeast Pacific on February 28th moved southeast, reaching southern Oregon/northern California on the 1st of March. This system brought high winds and snowfall to the Sierra Nevada and western Nevada through the 3rd. Several school and business closures occurred due to the heavy snowfall.
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 28, 9:53 PM PST, 2 hours 7 minutes earlier.
Area Forecast Discussion
National Weather Service Reno NV
953 PM PST Wed Feb 28 2018
.UPDATE...
The forecast still looks on track late this evening and overnight.
Snow is falling along the western edges of the forecast area at
this time with chain controls in place over I-80 and west of
Sierraville...Susanville...and Cedarville. The latest model
guidance still shows the start of the heaviest precipitation by
early Thursday morning...lasting through much of the day and into
Thursday evening. We will not plan any significant update this
evening.
&&
.PREVIOUS DISCUSSION... /Issued 309 PM PST Wed Feb 28 2018/
SYNOPSIS...
A strong winter storm will impact travel in the Sierra and
western Nevada Thursday through Saturday with blizzard conditions
Thursday through early Friday morning along Sierra passes and in
Mono County. Snow accumulation is likely in western Nevada with
periods of low visibility possible. A break is expected by late
weekend with another storm possible for the middle of next week.
SHORT TERM...
Main change to the forecast today was to issue a Blizzard Warning
for Mono County and the central Sierra. Strong winds Thursday
through Thursday night are expected to combine with snowfall
rates of 2-4 inches per hour. This will create dangerous,
potentially life threatening conditions over the high Sierra.
Extended travel delays are highly likely and road closures are
possible. In addition, the Sierra Avalanche Center has issued an
Avalanche Watch for Thursday morning through Saturday morning for
increasing avalanche danger.
Bottom line - I've lived in the Sierra for many years and I
wouldn't try to travel over Donner Summit or drive on highway 395
through Mono County during the heart of this storm.
The timing of the worst conditions for travel are as follows:
Central Sierra - Thursday morning through Thursday night.
Mono County - Thursday morning through early Friday afternoon.
Reno/Carson and surrounding areas of western Nevada - Thursday
afternoon through Thursday night.
Blizzard conditions are unlikely in the lower elevations of
western Nevada and in northeast California. But, snow combined
with gusty winds will likely create periods of low visibility
which will increase the hazard of travel on snow covered roads.
No major changes to the forecast snow amounts today. For all of
the forecast snow amounts around the region, please refer to the
Winter Weather products.
Snow will continue in the Sierra and Mono County through Saturday
morning, but winds are expected to weaken enough that blizzard
conditions should subside by Friday morning in the Tahoe Basin and
by Friday afternoon in Mono County.
Strong winds are expected ahead of and during the first part of
the storm. 700 mb flow increases to around 60kts with good low
level instability and mixing expected to create widespread gusts
of 40-50 mph with gusts in wind prone areas of 60-70 mph. While
winds of this caliber aren't that unusual here, what is unusual
about this storm is that strong winds are expected to continue
during heavy snowfall in the Sierra. For aviation interests in the
lee of the Sierra, turbulence is guaranteed with periods of low
level wind shear probable. Winds are also expected to be a concern
for high profile vehicles with travel restrictions possible.
It looks like winter finally decided to show up. While this storm
likely isn't going to be record breaker, it's still a serious
Sierra storm and you should treat the conditions accordingly.
-Zach
LONG TERM...Saturday through Wednesday...
The upper low will be moving overhead Saturday with the front and
jet dynamics moving out of the area. This will result in more
showery conditions with best chances for additional snow
accumulations in the Sierra as moist upslope flow persists in the
cold and unstable airmass. The upper low then progresses east out of
the area Saturday night and Sunday as an upstream low drops south
from the Gulf of Alaska. Showers will quickly diminish with more
stable conditions spreading across the region. Temperatures will
remain well below average for the weekend.
A shortwave ridge will dominate for Mon-Tue with quiet weather
conditions. There are indications of another storm approaching for
next Wednesday; however, the timing and strength of that system are
of low confidence as some simulations leave the system well off the
California coast. In any case, if that system does come in the snow
levels will be much higher than with this week's system given a
milder Pacific source. Temperatures are expected to rise to near
average by the middle of next week as the milder Pacific airmass
moves into northeast California and western Nevada. -Snyder/Hohmann
AVIATION...
VFR conditions can be expected through this evening. Increasing
winds and turbulence tonight will become very strong by sunrise
Thursday morning and persist through the day as a strong cold
front works into the region. Based on terrain channeling at KTVL
and local effects from Rattlesnake Mountain in southerly flow for
KRNO, low-level wind shear is a good bet Thursday until the front
moves through. Also, significant cross winds are a good bet for
KCXP.
A very cold storm is forecast for Thursday through Saturday,
bringing significant snowfall to the Sierra and far western Nevada,
with some snow out into west-central NV including KLOL/KNFL/KHTH.
Prolonged periods with below landing minimum CIGS/VIS are expected
for KTRK/KTVL late tonight into Saturday, with below published
minimums likely at times Thursday evening into Friday morning for
KRNO/KCXP.
Impacts of snowfall on paved areas/tarmac, especially in the lower
valleys of northeast CA and western NV, will be dependent on time of
day (harder to accumulate between 9 AM - 4 PM) and snowfall
intensity (heavy snow for more than 10-15 minutes can begin to
accumulate even in the daytime). However, note that the heaviest
snowfall through Friday in western NV is expected Thursday evening
through Friday morning when the sun is not as much an issue for
accumulations.
Snowfall accumulation projections and approximate times for heaviest
snow at area terminals:
KRNO: Friday 00Z-15Z (2-4")
Saturday 00Z-12Z Saturday (up to 2")
KCXP: Friday 00Z-15Z (2-4")
Saturday 00Z-12Z (up to 2")...more possible if lake effect snow
forms off of Lake Tahoe (low confidence)
KTRK: Thursday 12Z-Friday 18Z (10-15")
Friday 21Z-Saturday 12Z (4-8")
KTVL: Thursday 12Z-Friday 18Z (12-18")
Friday 21Z-Saturday 12Z (5-10")
KMMH: Thursday 21Z-Friday 18Z (6-12")
-Snyder/Hohmann
&&
.REV Watches/Warnings/Advisories...
NV...Winter Weather Advisory until 4 AM PST Friday NVZ005.
Winter Storm Warning until 8 AM PST Thursday NVZ002.
Winter Storm Warning from 4 AM Friday to 10 AM PST Saturday
NVZ002.
Blizzard Warning from 8 AM Thursday to 4 AM PST Friday NVZ002.
Wind Advisory from noon to 10 PM PST Thursday NVZ001-004.
Winter Weather Advisory from 4 PM Thursday to 10 AM PST Friday
NVZ003.
Wind Advisory from 1 AM to 4 PM PST Thursday NVZ003.
CA...Winter Storm Warning until 10 AM PST Saturday CAZ071.
Winter Weather Advisory until 4 AM PST Friday CAZ070.
Winter Storm Warning from 4 AM to 10 AM PST Thursday CAZ073.
Winter Storm Warning from 1 PM Friday to 10 AM PST Saturday
CAZ073.
Blizzard Warning from 10 AM Thursday to 1 PM PST Friday CAZ073.
Winter Storm Warning until 8 AM PST Thursday CAZ072.
Winter Storm Warning from 4 AM Friday to 10 AM PST Saturday
CAZ072.
Blizzard Warning from 8 AM Thursday to 4 AM PST Friday CAZ072.
&&
For more information from the National Weather Service visit...
http://weather.gov/renoThe national radar mosaic for the moment the first event began.
13 heavy snow, 2 avalanche, 1 blizzard. Local standard time, as filed.
Trained weather spotter 2 miles northwest of Meyers reported 14.5 inches of snow from 2 March 0733PST to 3 March 0733PST. 48 hour total snowfall of 30 inches beginning 1 March 0733PST and ending 3 March at 0733PST.
Trained weather spotter 1 mile north-northwest of Homewood reported 18 inches of snow fall in a 24 hour period from 2 March 0910PST to 3 March 0910PST. 48 hour total snow fall of 50.5 inches from 1 March 0910PST to 3 March 0910PST.
Squaw Valley Ski Resort reported 68 inches of snowfall in a 48 hour period from 1 March 0948PST to 3 March 0948PST.
Homewood Ski Area reported 50.5 inches of snowfall at an elevation of 6330 feet from 1 March 0937PST to 3 March 0937PST.
Heavenly Ski Resort reported 54 inches of snowfall in a 48 hour time period from 1 March 0945PST to 3 March 0945PST.
Trained weather spotter 1 mile north-northwest of Portola reported a 48 hour total snowfall of 13.5 inches from 1 March 0915PST to 3 March 0915PST.
CoCoRaHS station CA-SI-2, 1 mile southwest of Sierraville reported that 9 inches of snow fell in a 12 hour period from 2 March 0700PST to 3 March 0700PST.
Trained weather spotter 6 miles west-northwest of Bridgeport reported 40 inches of snowfall in a 48 hour period from 1 March 0941PST to 3 March 0941PST.
Mammoth Mountain Ski Resort reported 62 inches of snowfall in a 48 hour period from 1 March 0950PST to 3 March 0950PST.
June Lake Ski Area reported 72 inches of snowfall in a 48 hour period from 1 March 0949PST to 3 March 0949PST.
Trained weather spotter 1 mile south-southwest of Boca Reservoir reported 20.5 inches of snowfall in a 48 hour period from 1 March 0700PST to 3 March 0700PST.
Trained weather spotter in Tahoe City reported 30 inches of snowfall in a 48 hour period from 1 March 0700PST to 3 March 0700PST.
Northstar Ski Resort reported 52 inches of snowfall in a 48 hour period from 1 March 0946PST to 3 March 0946PST.
Interstate 80 closed from Colfax, CA, to the Nevada State line due to high winds, heavy snowfall, and whiteout conditions. The closure of Interstate 80 lasted from the early afternoon of 1 March through the late morning of 2 March. Chain and snow tires were required on several roads around the Greater Lake Tahoe Area. A snowboarder became lost during the blizzard conditions the night of the 1st and was found deceased near Squaw Valley Ski Resort 2 March at 1017PST. The cause of death from several reports is undetermined. Wind gusts during peak blizzard conditions ranged from 47 to 63 mph in the Greater Lake Tahoe area below 8,000 feet MSL, with the highest wind gust of 146 mph reported at 1 March 2134PST from a mesonet atop the summit of Squaw Valley.
An avalanche occurred at approximately 1340PST on 2 March at the base of the Olympic Lady chair lift at Squaw Valley Ski resort. The avalanche caught five people. One person sustained a serious lower body injury. A second guest had to be rescued, but was taken to the base of Squaw Valley and released. Three others left unharmed, according to KOLO8 News Reno.
An avalanche at Mammoth Mountain occurred at approximately 1015PST on 3 March during a avalanche hazard mitigation search performed by the area ski patrol. The snow slid down down a steep run and funneled into a narrow chute named Upper Dry Creek before coming to a stop a the base of a chairlift. Six Mammoth Mountain employees at the lift were partially caught but freed themselves quickly, suffering only minor injuries. Source: Los Angeles Times.
As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.
| Event | Date | Age | Sex | Where | Kind |
|---|---|---|---|---|---|
| Blizzard, Greater Lake Tahoe Area | 2018-03-02 | 42 | Male | Outside/Open Areas | Indirect |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2018Every state in 2018This day in weather historyWarnings in California, March 2018
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: 747148, 747149, 747150, 747152, 747153, 747155, 747156, 747162, 747164, 747166, 747168, 747169, 747170, 747099, 747137, 747157.