Storm Summary Number 3 for Significant California Atmospheric River
NWS Weather Prediction Center College Park MD
700 AM PST Tue Jan 10 2023

...Significant heavy rainfall, mountain snow, and strong winds
will continue to impact CA and western NV into tonight...

Winter Storm Warnings are in effect over the Sierra Nevada,
Klamath Ranges, and portions of the central Rockies.

High Wind Warnings extend along much of coastal and southern
California

Flood Watches extend along much of coastal California, into the
Sacramento Valley.

Winter Weather Advisories are in effect for northern California,
central Nevada, the Wasatch Mountains, and much of the central and
northern Rockies.

Wind Advisories are in effect across much of California, southern
Nevada, and western portions of Utah and Arizona.

For a detailed graphical depiction of the latest watches, warnings
and advisories, please see www.weather.gov

At 600 AM PST...Current RADAR and surface observations detected
widespread moderate to heavy rainfall over much of California
associated with an intense atmospheric river plume surging inland
ahead of a cold front situated in the central and northern parts
of the state. The heaviest axis of precipitation was located to
the southeast of Sacramento in the northern portion of the San
Joaquin Valley. Snow was confined to the higher elevations of the
central and southern Sierra Nevada Range, with the heaviest
snowfall rates limited to higher elevations. Strong wind gusts
were also ongoing across much of southern California, especially
in the higher elevations of the Transverse and Sierra Nevada
Ranges.

...Selected preliminary Storm Total Snowfall in inches from 500 PM
PST Sun Jan 08 through 600 AM PST Tue Jan 10...

...CALIFORNIA...
LONE PINE 11 SW                      47.0                    
SOUTH LAKE 1 NNE                     41.0                    
ROUND VALLEY 9 WNW                   32.0                    
MAMMOTH MOUNTAIN SKI BASE            18.0                    
SUSANVILLE 5 WNW                     15.0                    
SODA SPRINGS 2 ENE                   14.0                    
WILLOW CREEK 4 WSW                   14.0                    
BEAR VALLEY 2 N                      12.0                    
DEEP SPRINGS 11 WSW                  12.0                    

...Selected preliminary Storm Total Rainfall in inches from 500 PM
PST Sun Jan 08 through 600 AM PST Tue Jan 10...

...CALIFORNIA...
SAN MARCOS PASS                     17.11                    
NORDHOFF RIDGE                      17.01                    
ALISAL RESERVOIR                    13.82                    
ROCKY BUTTE                         12.91                    
THREE PEAKS (SANTA LUCIA)           12.75                    
DOULTON TUNNEL                      11.90                    
HOPPER CANYON                       10.79                    
NATURE POINT NEAR BASS LAKE          9.60                    
MONTECITO                            8.85                    
CHALK PEAK                           8.58                    
MINING RIDGE                         8.40                    
DINKEY                               7.20                    
SAN FRANCISCO INTL AIRPORT           1.84                    
SANTA MONICA                         1.56                    
LOS ANGELES INTL AIRPORT             1.51                    
SACRAMENTO INTL AIRPORT              1.43                    

...NEVADA...
GENOA                                1.95                    
KINGS CANYON                         1.84                    
GLENBROOK                            1.26                    

...Selected preliminary Peak Wind gusts in miles per hour earlier
in the event...

...CALIFORNIA...
COPPER CANYON                          98                    
WASHOE CITY 2 NNE                      98                    
AGUA DULCE 8 S                         88                    
WEITCHPEC 11 WSW                       86                    
HIGH GLADE LOOKOUT                     80                    
JOAQUIN RANGE                          78                    
KNEELAND 6 SSE                         77                    
SILVERWOOD LAKE                        76                    
SANDSTONE PEAK                         71                    
CAYUCOS 7 N                            69                    
CRESCENT CITY 3 NW                     68                    

...OREGON...
YACHATS 2 SE                           86                    
GARIBALDI 2 WNW                        83                    
PILOT ROCK 9 S                         75                    

...WASHINGTON...
FRANCES 6 ESE                          68                    
RYDERWOOD 2 SW                         58                    
TOKELAND 1 ESE                         57                    


The barrage of heavy rainfall, mountain snow, and strong winds
will persist today across central and southern California as the
Atmospheric River slowly shifts southward. Areas in southern
California will experience the most substantial precipitation
impacts, as a swath of heavy precipitation crosses the state
today. Areas further north will experience lingering impacts
through today as onshore flow to the south of the low will
continue to bring moisture into the region. The cumulative effect
of successive heavy rain events will lead to additional
considerable flood impacts, including rapid water rises and
mudslides across California and portions of far western Nevada.
Numerous instances of flash flooding and debris flows are
possible, especially over burn scar areas. Scattered power outages
are also likely due to the strong wind gusts. Atop the Sierra
Nevada peaks, additional snowfall totals of 1-4 feet will lead to
dangerous travel above 4000 feet today and into tonight. Mountain
communities will be at increasing risk of infrastructure impacts
and avalanches as snow load continues to rapidly increase.

The next Storm Summary will be issued by the Weather Prediction
Center at 700 PM PST. Please refer to your local National Weather
Service office for additional information on this event.

Russell/Genz