Alert archive / California / Flash Flood Warnings in 1993

Flash Flood Warning 2, NWS San Francisco Bay Area, CA

January 13, 1993Santa Clara County, Santa Cruz County, California

NWS San Francisco Bay Area, CA issued this flash flood warning at Jan 13, 1993, 6:10 AM PST for Santa Clara County, Santa Cruz County, California. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued
Jan 13, 1993, 6:10 AM PST (14:10 UTC)
Expired
Jan 13, 1993, 9:00 AM PST
In force
3 hr
Issued by
NWS San Francisco Bay Area, CA
Area
Whole counties

Counties Santa Clara County, CA, Santa Cruz County, CA

The nearest sounding before it

Oakland, CA (KOAK), launched 12:00Z, 2.2 hours before the alert went out and 74 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 1993-01-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Oakland, CA at 12:00Z on 1993-01-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 153 square meters per square second.193958Sfc1 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
604 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
153 m²/s²
0-3 km storm-relative helicity
181 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 131420
FFWSFO
CAC001-013-085-087-131700-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
610 AM PST WED JAN 13 1993
 
THE NATIONAL WEATHER SERVICE IN SAN FRANCISCO HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL  9 AM PST
FOR PEOPLE IN THE FOLLOWING LOCATIONSS...
 
IN CENTRAL CALIFORNIA
 
...FLASH FLOOD WARNING FOR SOUTHER/EASTERN ALAMEDA COUNTY AND ALL OF
CONTRA COASTA COUNTY...
...FLASH FLOOD AND MUDSLIDE/DEBRIS FLOW WARNING FOR SOUTHERN/WESTERN
SANTA CLARA COUNTY AND SANTA CRUZ COUNTY...
 
AT 5.45 AM PST...THE CONTRA COUNTY SHERIFFS DISPATCH REPORTED CREEKS
OVERFLOWING WITH SOME FLOODING OF BUILDINGS NEAR THE CREEKS.
HIGHWAY 680 NEAR WALNUT CREEK WAS CLOSED SOUTHBOUND DUE TO FLOODING.
 
AT 6 AM PST...THE ARROYO DE LA LAGUNA NEAR PLEASANTON IN ALAMEDA COUNTY
WAS AT 16.7 FEET AND THE FLOOD STAGE IS 17.0 FEET. THE WATER FLOWING
THROUGH THE ARROYO DE LA LAGUNA WILL EMPTY INTO ALAMEDA CREEK IN NILES
CANYON.
 
AT 6 AM PST...THE  LLAGAS CREEK NEAR GILROY WAS RISING RAPIDLY AND
WAS REPORTED TO BE FLOODING. THE SAN LORENZO RIVER WAS UP TO
13.7 FEET WHICH WAS JUST BELOW THE THE FLOOD STAGE OF 14 FEET.
 
A FLASH FLOOD WARNING MEANS THAT FLOODING IS OCCURRING OR IS
IMMINENT.  MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES.  DO NOT
ATTEMPT TO CROSS BRIDGES...DIPS...OR LOW SPOTS IF WATER COVERS
THE ROADWAY.  NEVER TRY TO CROSS A FLOWING STREAM...EVEN A SMALL
ONE...ON FOOT.  TO ESCAPE RISVING WATER MOVE UP TO HIGHER GROUND.
 
IN ADDITION...THE HEAVY RAIN WILL CAUSE SOME MUDSLIDES IN SLIDE PRONE
AREAS...ESPECIALLY THE SANTA CRUZ MOUNTAINS.
 
HELLER

The office that day

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

IssuedProductOfficeCountiesLasted
Jan 13, 4:10 AM PSTFlash Flood WarningMTRMarin5 hr
Jan 13, 6:10 AM PSTFlash Flood WarningMTRAlameda, Contra Costa3 hr
Jan 13, 9:18 AM PSTFlash Flood WarningMTRAlameda3 hr

Nearby

Flash Flood Warnings in California, 1993Every flash flood warning in 1993

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.