Storm Summary Number 2 for Heavy Rainfall and High Wind Associated
with Tropical Storm Hilary
NWS Weather Prediction Center College Park MD
800 PM PDT Sun Aug 20 2023

...Widespread heavy rainfall and strong winds to occur from
Southern California and the Great Basin tonight to portions of the
Northern Rockies into Monday morning as Hilary tracks north...

Tropical Storm Warnings are in effect over Southern California
(including the San Diego and Los Angeles metropolitan areas).

Flash Flood Warnings are in place throughout much of Southern
California.

Flood Watches extend across Southern California northward into the
Great Basin and interior Northwest.

High Wind Warnings extend across portions of the Mojave and
Sonoran Deserts northward into the Great Basin and Northern
Rockies.

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

At 700 PM PDT...Latest surface observations and regional radar
mosaic depict widespread moderate to heavy rainfall across much of
Southern California northward into the Great Basin. Heavy showers
have also been detected over central Arizona and as far north as
the Snake River Valley. The expansive shield of rainfall is
occurring ahead of Tropical Storm Hilary, analyzed by the National
Hurricane Center with a position of 33.6N, 117.1W. Note: rainfall
observations for California and Arizona were collected beginning
this Friday at 7 AM PDT, while observations over Nevada were
collected starting Saturday at 7 AM PDT.

...Selected preliminary Storm Total Rainfall in inches from 700 AM
PDT Fri Aug 18 through 700 PM PDT Sun Aug 20...

...ARIZONA...
YELLOW JOHN MOUNTAIN                 1.33                    
MUSIC MOUNTAIN                       1.15                    
PARKER                               1.11                    
YUMA PROVING GROUND                  0.79                    
PLEASANT VALLEY                      0.73                    

...CALIFORNIA...
MT. SAN JACINTO                      8.52 ELEVATION 8616FT   
HEART BAR                            6.91 ELEVATION 6690FT   
MT LAGUNA                            6.88 ELEVATION 6000FT   
RANCHITA                             6.78 ELEVATION 4180FT   
RAYWOOD FLATS                        6.77 ELEVATION 7079FT   
LEONA VALLEY                         6.15                    
WRIGHTWOOD                           5.50 ELEVATION 5950FT   
UPPER TAHQUITZ CREEK                 5.12 ELEVATION 5600FT   
PHELAN 1 W                           4.39                    
WALKER PASS                          4.19 ELEVATION 5572FT   
PINE MOUNTAIN CLUB                   3.75                    
BIG BEAR CITY 3 ENE                  3.59                    

...NEVADA...
BRISTLECONE TRAIL                    6.00 ELEVATION 8906FT   
LEE CANYON                           4.80 ELEVATION 8618FT   
RAINBOW CANYON                       3.40                    
YUCCA MOUNTAIN                       2.81                    
KYLE CANYON                          2.01                    
ASH MEADOWS                          2.00                    

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

...ARIZONA...
YUMA ARPT                              69                    
SAFFORD 4 ENE                          60                    
BENDER SPRINGS                         59                    
MOBILE 2.2 SE                          47                    
GILA BEND                              46                    

...CALIFORNIA...
BIG BLACK MOUNTAIN                     84                    
ESSEX 10 SSE                           83 OLD WOMAN MOUNTAIN 
PALOMAR MTN LOOKOUT                    79                    
PIGSAH PEAK                            79                    
HAUSER MOUNTAIN                        78                    
VALLEY CENTER 7 E                      70                    
CRESTLINE 5 NW                         69                    
SANTA CLARITA 10 ESE                   64 ELEVATION 4483FT   
THOUSAND OAKS 8 SW                     57 BONEY MOUNTAIN     
OCEANSIDE 5 NW                         52 CAMP PENDLETON     


Tropical Storm Hilary is forecast to continue its track north into
the heart of the Great Basin tonight. Even after Hilary becomes a
post-ropical storm, its remnant moisture will still be responsible
for rounds of heavy rainfall and high wind gusts throughout the
West on Monday. For more information regarding the track of
Hilary, refer to the National Hurricane Center at nhc.noaa.gov.
Potentially historic rainfall is expected to cause additional
flash, urban, and arroyo flooding across the Southwestern U.S.
Dangerous to locally catastrophic flooding impacts are expected
through Monday morning. Flash flooding is also anticipated across
portions of the interior Northwest through Monday and Tuesday. For
more information regarding the excessive rainfall associated with
Tropical Storm Hilary, please visit wpc.ncep.noaa.gov.

The next Storm Summary will be issued by the Weather Prediction
Center at 800 AM PDT. Please refer to your local National Weather
Service office for additional information on this event.

Mullinax