STORM SUMMARY NUMBER 3 FOR WEST COAST ATMOSPHERIC RIVER AND HEAVY
RAIN
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
800 AM PDT SAT APR 07 2018

...HEAVY RAIN IS FALLING ACROSS CENTRAL CALIFORNIA AS AN
ATMOSPHERIC RIVER PROVIDES RECORD-BREAKING MOISTURE... 

FLOOD WATCHES ARE IN EFFECT FOR PORTIONS OF NORTHERN AND CENTRAL
CALIFORNIA...PORTIONS OF WESTERN NEVADA AND IDAHO.

HIGH WIND WARNINGS ARE IN EFFECT FOR PORTIONS OF OREGON AND
WASHINGTON...NORTHERN CALIFORNIA AND NORTHERN NEVADA.

FOR A DETAILED GRAPHICAL DEPICTION OF THE LATEST
WATCHES...WARNINGS AND ADVISORIES...PLEASE SEE WWW.WEATHER.GOV

AT 700 AM PDT...A SURFACE LOW WITH A CENTRAL PRESSURE OF 968
MB...28.58 INCHES...WAS CENTERED APPROXIMATELY 275 MILES WEST OF
THE STRAIT OF JUAN DE FUCA/SOUTH VANCOUVER ISLAND AND MOVING
NORTHEASTWARD. AHEAD OF THE LOW PRESSURE SYSTEM A BROAD
ATMOSPHERIC RIVER WAS PROVIDING HIGH TO RECORD-BREAKING AMOUNTS OF
MOISTURE TO CALIFORNIA AND SOUTHERN OREGON...WITH MODERATE RAIN TO
NEVADA AND IDAHO. NATIONAL WEATHER SERVICE DOPPLER RADARS AND
SURFACE OBSERVATIONS INDICATED THAT MODERATE TO HEAVY RAIN WAS
FALLING ACROSS MUCH OF CENTRAL CALIFORNIA. LIGHT TO MODERATE RAIN
WAS FALLING ACROSS MUCH OF WASHINGTON...OREGON...NEVADA AND
SOUTHERN IDAHO. 

...SELECTED PRELIMINARY STORM TOTAL RAINFALL IN INCHES FROM 100 AM
PDT THU APR 05 THROUGH 700 AM PDT SAT APR 07...

...CALIFORNIA...
SHELTER COVE 0.6 NNE                  8.34                    
GUALALA 1.2 SE                        8.06                    
CAZADERO 5.6 W                        7.91                    
OCCIDENTAL 2.8 SW                     7.39                    
ALBION 4.0 SE                         7.09                    
SEBASTOPOL 4.5 WSW                    6.63                    
LAYTONVILLE 1.1 SW                    6.30                    
GUERNEVILLE 2.0 SSW                   5.92                    
MIDDLE PEAK RAWS                      5.79                    
MILL VALLEY 2 W                       5.69                    
BODEGA BAY 1.0 SE                     5.64                    
VENADO 7 NNW GUERNEVILLE              5.04                    
COMPTCHE 9 W                          4.28                    
DILLON BEACH                          4.22                    
LEGGETT 1 NW                          4.04                    
ROCKPORT 3 N                          4.00                    
WHITEHORN 2 WNW                       3.88                    
BLUE CANYON/NYACK ARPT                3.34                    
YOUNTVILLE 3 WSW                      3.04                    
SANTA ROSA/SONOMA CO. ARPT            2.98                    
UKIAH MUNI ARPT                       2.95                    
SAN FRANCISCO 1 SW                    2.93                    
OAKLAND 3 NE                          2.54                    
REDDING MUNI ARPT                     2.49                    
SACRAMENTO METRO ARPT                 1.27                    

...SELECTED PEAK WIND GUSTS IN MILES PER HOUR EARLIER IN THE
EVENT...

...CALIFORNIA...
BURNS CANYON                          62                    
WHITEWATER RAWS 2 N                   60                    
MOJAVE ARPT                           51                    


THE ATMOSPHERIC RIVER WILL CONTINUE TO SPREAD COPIOUS AMOUNTS OF
MOISTURE ONSHORE...PRODUCING HEAVY RAINFALL ALONG MUCH OF THE WEST
COAST TODAY. BY THIS AFTERNOON THE SURFACE LOW WILL APPROACH
BRITISH COLUMBIA WHILE THE COLD FRONT SWEEPS INLAND ACROSS THE
WEST COAST STATES...CUTTING OFF THE INFLOW OF DEEP MOISTURE INTO
THE WEST COAST. WHILE THE HEAVIEST RAINFALL RATES SHOULD BEGIN TO
WIND DOWN LATE SATURDAY...ONSHORE FLOW IN THE WAKE OF THE COLD
FRONT WILL KEEP SHOWERS IN PLACE INTO SUNDAY ACROSS THE PACIFIC
NORTHWEST. ADDITIONAL RAINFALL AMOUNTS OF 2 TO 4 INCHES ARE
POSSIBLE THROUGH SUNDAY FROM WESTERN WASHINGTON AND OREGON
SOUTH...ESPECIALLY AT THE HIGHER ELEVATIONS WHERE OROGRAPHIC LIFT
WILL ENHANCE PRECIPITATION RATES. UP TO 1 INCH OF ADDITIONAL
RAINFALL IS EXPECTED IN CENTRAL CALIFORNIA.

THE NEXT STORM SUMMARY WILL BE ISSUED BY THE WEATHER PREDICTION
CENTER AT 200 PM PDT. PLEASE REFER TO YOUR LOCAL NATIONAL WEATHER
SERVICE OFFICE FOR ADDITIONAL INFORMATION ON THIS EVENT.

CAMPBELL