An upper level low over northern California yielded a cooler, wetter, and breezy pattern across the region through Labor Day weekend. Periods of light to moderate precipitation intermingled with isolated thunderstorms produced brief periods of heavy rainfall across the Sierra into northwest Nevada that caused some flash flooding and flooding concerns through the Labor weekend.
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.
An upper level low over northern California yielded a cooler, wetter, and breezy pattern across the region through Labor Day weekend. Periods of light to moderate precipitation intermingled with isolated thunderstorms produced brief periods of heavy rainfall across the Sierra into northwest Nevada that caused some flash flooding and flooding concerns through the Labor weekend. Of particular concern was flooding in the playa area of the Black Rock Desert during the Burning Man festival. A few isolated severe thunderstorms occurred across parts of the Basin and Range east of US-95 in Pershing, Churchill, and Mineral counties as well.
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 Sep 1, 12:47 PM PST, 13 minutes earlier.
Area Forecast Discussion
National Weather Service Reno NV
147 PM PDT Fri Sep 1 2023
.SYNOPSIS...
Low pressure holding over northwest California will bring windy
conditions through this evening, with cool and wet conditions
mainly over northeast California slowly spreading east across the
region through Sunday. Drier weather then returns from Monday
onward as this low exits, with temperatures warming to near early
September averages by later next week.
&&
.DISCUSSION...
An upper level low over northern California will remain nearly
stationary through Saturday afternoon, then push eastward across
western NV Sunday. This setup will favor the heaviest rain shower
bands with embedded thunderstorms setting up over northeast CA-
far northwest NV through Saturday afternoon. These shower bands
will then spread across the remainder of the eastern Sierra and
western NV Saturday night through Sunday. Gusty winds also
continue into this evening with peak speeds across west central NV
from US-50 southward to Mono County. Daytime temperatures will be
15-25 degrees below average from Reno-Tahoe northward through
Saturday, and regionwide Sunday.
Drier and warmer conditions will return beginning on Labor Day
and continue through next week. Additional details below:
WIND:
* Wind gusts will peak this afternoon through early evening in the
advisory areas of Mineral-Mono-Southern Lyon counties, where
lower elevations can expect gusts of 40-50 mph while wind prone
areas and higher elevation sites could see gusts 50-70 mph, with
some ridge top gusts of 80+ mph along the Sierra crest. For
areas included in lake wind advisories, peak gusts of 30-40 mph
are expected, which have been occurring at the Lake Tahoe buoys
since early this morning.
* For Saturday, we could still see some breezy conditions in areas
south of US-50, but gusts will be lower, generally in the 30-40
mph range, with Sierra crest ridge top gusts up to 60 mph.
Lighter winds then prevail regionwide for Sunday and Labor Day.
PRECIPITATION:
* So far, the heaviest rainfall amounts (0.25-0.50") have occurred
across northeast CA and far northwest NV west of Gerlach, but
amounts then drop off sharply (0.10" or less) south and east of
these areas. While hourly rainfall rates have generally been
0.10" or less, some of the heavier bands produced rates up to
0.20"/hour. Most of these areas can withstand these rainfall
rates with few impactful flood risks, but parts of the Dixie
Fire burn scar could be at risk for mud or debris flows if
prolonged heavier rainfall rates occur. 1-2" storm totals can't
be ruled out for parts of Lassen and Plumas Counties, the
Surprise Valley, and adjacent sections of far northwest NV until
the rain bands shift east during the day Sunday.
* For the remainder of the region, lesser rainfall amounts are
expected, with the most likely totals between 0.50-1" for the
Tahoe basin, and between 0.10-0.25" with a few localized totals
up to 0.50" for much of western NV and Alpine-Mono counties. For
Sunday afternoon, some of the guidance brings potential for
scattered thunderstorms producing heavier rainfall east of US-95
in west central NV. Depending on where the low eventually tracks
and if some heavier rain bands persist, there remains a slight
10-20% chance that a few locations could receive up to double
the aforementioned amounts.
* For the highest Sierra elevations near or above 10,000 feet, a
touch of snow could occur especially on Sunday as the main low
swings through. While travel impacts aren't likely, anyone
camping or hiking in the high Sierra backcountry could encounter
some snowflakes in the air with temperatures hovering in the
30s.
* From Monday onward, generally dry weather is expected to
prevail, although a few ensemble members show a weak trailing
shortwave passage either Monday or Tuesday, which could bring a
few showers mainly north of I-80.
TEMPERATURES:
* Through Saturday, the much cooler than average temperatures will
hold across areas west of US-95, while highs hang on to the 80s
for west central NV and the US-6 corridor of southeast Mono
County. The overall coolest day across the region will be Sunday
with highs only in the 60s to lower 70s for lower elevations
and 50s near the Sierra, about 20 degrees below average.
* Sunday night and Monday night will be on the chilly side, with
lows dipping to near the freezing mark across Sierra valleys and
40s for most lower elevations.
* A warming trend returns beginning on Labor Day as highs rebound
to the mid 70s across western Nevada and upper 60s for Sierra
valleys. Highs are expected to return to near early September
averages (mid 80s for lower elevations/mid 70s for Sierra
valleys) by late week.
MJD
&&
.AVIATION...
Gusty south to southwest winds of 25-35 kts will continue through
around 03Z before gradually tapering off overnight. This will
produce turbulence across the area, with LLWS anticipated over
the Sierra terminals overnight. Winds will return Saturday,
although gusts not as strong compared to today.
Periods of rain showers with embedded thunderstorms will impact
W Nevada and NE California terminals through Sunday, with the
exception of KMMH that should remain mostly dry during this
period. This precipitation will bring mountain obscurations and
MVFR visibilities (perhaps briefly IFR conditions in heavier
convection).
-Dustin
&&
.FIRE WEATHER...
* Wind advisories are in effect this afternoon and evening for
Mono and Mineral/southern Lyon counties. Fuel moisture status
remains below critical thresholds in these areas per the latest
fuel analysis, but it is always important to exercise caution
and avoid activities that could start a fire when stronger winds
at these speeds are occurring.
* Otherwise, increasing moisture/wetting rain chances and
unseasonably cool temperatures will reduce fire weather concerns
through the Labor Day weekend. Some breezy wind gusts of 30-40
mph could linger on Saturday for areas south of US-50, otherwise
lighter winds will prevail through the remainder of the weekend.
MJD
&&
.REV Watches/Warnings/Advisories...
NV...Lake Wind Advisory until 8 PM PDT this evening for Lake Tahoe in
NVZ002.
Wind Advisory until 8 PM PDT this evening NVZ001.
Lake Wind Advisory until 8 PM PDT this evening for Washoe Lake
in NVZ003.
Lake Wind Advisory until 8 PM PDT this evening NVZ004.
CA...Lake Wind Advisory until 8 PM PDT this evening for Lake Tahoe in
CAZ072.
Wind Advisory until 8 PM PDT this evening CAZ073.
&&The Reno radar (KRGX), 85 km away, was scanning. The volume nearest the first event began at 20:58 UTC.
5 heavy rain, 2 debris flow, 1 high wind, 1 hail. Local standard time, as filed.
A CO-OP Observer located 1.0 mi S of Glenbrook, NV, reported a storm total rainfall amount of 0.67 inches.
A mesonet station (LVYN2-Little Valley) located 2.0 mi ESE of Diamond Peak Ski resort reported a storm total rainfall amount of 0.55 inches.
The public located 11.0 mi NE Gerlach, NV reported that the 24 hr storm total rainfall amount of 0.6-0.8 inches had fallen during Burning Man Festival at Black Rock City, NV.
Mesonet station (SLIDE-DRI) located 0.9 mi E of Mount Rose Summit reported a peak wind gust of 71 mph.
A trained spotter located 1.0 mi NE of Hawthorne, NV, reported a severe thunderstorm dropped several dime to half-inch size hailstones along with a few one-inch size hailstones.
A CO-OP Observer located 1.6 mi S of Carson City, NV, and a CoCoRAHs Station (NV-CC-14) located 4.4 mi N of Carson City, NV, reported storm total rainfall amounts of 0.70 and 0.56 inches respectively.
Nevada Department of Transportation (NDOT) reported flash flooding 5.0 mi N of Luning, NV. This event was initiated by a stronger thunderstorm producing heavy rainfall and hail that caused debris flows and flooding across Nevada State Route 361. Nevada State Route 361 was closed briefly from 1:18 PM PST to 2:26 PM PST until NDOT opened one lane with a pilot car.
Nevada Department of Transportation (NDOT) reported a second flash flooding event 8.0 mi S of Hawthorne, NV when strong thunderstorms producing heavy rainfall caused debris flows and flooding across Nevada State Route 359. A partial collapse occurred on the southbound lane of Nevada State Route 359 that closed the road at 4:11 PM PST, Sunday, September 3, 2023.
A CoCoRAHs station (NV-CH-9) located 2.1 SSE of Fallon, NV, as well as mesonet stations located 13.6 mi NE of Schurz (RHDFL-DRI), 7.0 mi E of Dixie Valley (CYVN2-Cherry Valley), NV, and 9.8 mi NE of Cold Springs (EDCVY-DRI), NV, reported storm total rainfall amounts of 1.09, 0.91, 1.95, and 2.4 inches respectively.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Nevada in 2023Every state in 2023This day in weather historyWarnings in Nevada, September 2023
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: 1143009, 1143011, 1143010, 1143008, 1143085, 1143090, 1143088, 1143089, 1143092.