Alert archive / California / Flash Flood Warnings in 1997

Flash Flood Warning 34, NWS San Francisco Bay Area, CA

January 22, 1997Contra Costa County, California

NWS San Francisco Bay Area, CA issued this flash flood warning at Jan 22, 1997, 2:15 PM PST for Contra Costa County, California. It was in force for 4 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jan 22, 1997, 2:15 PM PST (22:15 UTC)
Expired
Jan 22, 1997, 6:00 PM PST
In force
4 hr
Issued by
NWS San Francisco Bay Area, CA
Area
Whole counties

County Contra Costa County, CA

The radar

The Sacramento radar (KDAX), 69 km from the middle of the area, began a volume at 22:15 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Oakland, CA (KOAK), launched 12:00Z, 10.3 hours before the alert went out and 31 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Oakland, CA at 12:00Z on 1997-01-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Oakland, CA at 12:00Z on 1997-01-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 131 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
542 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
131 m²/s²
0-3 km storm-relative helicity
285 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KSFO 222216
FFWSFO
CAC097-055-041-013-075-230200-
 
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
215 PM PST WED JAN 22 1997
 
THE NATIONAL WEATHER SERVICE IN SAN FRANCISCO HAS ISSUED A FLASH
FLOOD WARNING UNTIL 6PM FOR THE FOLLOWING LOCATIONS OF THE NORTHERN
SAN FRANCISCO BAY AREA...
 
IN CENTRAL CALIFORNIA
     ...SONOMA...NAPA...MARIN...SAN FRANCISCO AND CONTRA COSTA
       COUNTIES...

AT 200 PM RADAR...SATELLITE...AND SPOTTER REPORTS ARE INDICATING VERY
HEAVY RAINFALL MOVING THROUGH THE NORTHERN SAN FRANCISCO BAY AREA.
STRONG CELLS...SOME WITH POSSIBLE THUNDERSTORMS... ARE CURRENTLY ON A
LINE FROM ABOUT SAN FRANCISCO TO NAPA. RAINFALL RATES IN THE NORTH
BAY HAVE EXCEEDED .5 INCHES IN THE PAST HOUR. THESE STORMS WILL MOVE
SOUTH AND EAST AND WEAKEN LATE THIS AFTERNOON. 

THESE STORMS WILL CAUSE FLOODING OF STREAMS...CREEKS AND URBAN AREAS
AS WELL AS MUDSLIDES. PERSONS IN THE REGION SHOULD WATCH FOR RAPIDLY
RISING WATER AND SLIPPAGE OF UNSTABLE HILLSIDES.

A FLASH FLOOD WARNING MEANS THAT FLOODING OCCURRING OR IS IMMINENT. 
ITS IMPORTANT TO KNOW WHERE YOU ARE RELATIVE TO STREAMS... RIVERS...
OR CREEKS WHICH CAN BECOME KILLERS IN HEAVY RAINS. MUDSLIDES ARE ALSO
POSSIBLE.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY.
MOVE TO HIGHER GROUND.                            
 
JAN NULL
LEAD FORECASTER

The office that day

Everything else NWS San Francisco Bay Area, CA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 22, 2:15 PM PSTFlash Flood WarningMTRNapa, Sonoma4 hr
Jan 22, 2:15 PM PSTFlash Flood WarningMTRMarin4 hr
Jan 22, 2:15 PM PSTFlash Flood WarningMTRCity and County of San Francisco4 hr

Nearby

Flash Flood Warnings in California, 1997Every flash flood warning in 1997

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.