Alert archive / California / Flash Flood Warnings in 2003

Flash Flood Warning 7, NWS San Diego, CA

August 20, 2003Riverside County, San Diego County, California

NWS San Diego, CA issued this flash flood warning at Aug 20, 2003, 1:04 PM PDT for Riverside County, San Diego County, California. It was in force for 86 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 20, 2003, 1:04 PM PDT (20:04 UTC)
Expired
Aug 20, 2003, 2:30 PM PDT
In force
86 min
Issued by
NWS San Diego, CA
Area
Whole counties

Counties Riverside County, CA, San Diego County, CA

The radar

The San Diego radar (KNKX), 80 km from the middle of the area, began a volume at 20:06 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

San Diego, CA (KNKX), launched 12:00Z, 8.1 hours before the alert went out and 100 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, San Diego, CA at 12:00Z on 2003-08-20Temperature 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 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, San Diego, CA at 12:00Z on 2003-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 71 square meters per square second.1939Sfc1 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
1174 m above ground
0-6 km bulk shear
4 kt
0-1 km storm-relative helicity
71 m²/s²
0-3 km storm-relative helicity
61 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 
WGUS56 KSGX 202005
FFWSGX
CAC065-073-202130-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN DIEGO CA
104 PM PDT WED AUG 20 2003

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  THE MOUNTAINS AND DESERTS OF WESTERN RIVERSIDE COUNTY...INCLUDING  
  PALM CANYON AND THE CITIES OF...PALM SPRINGS...PALM DESERT         
  AND CATHEDRAL CITY
  ALL MOUNTAIN AND DESERT AREAS OF SAN DIEGO COUNTY IN SOUTHWEST     
  CALIFORNIA

* UNTIL 230 PM PDT

* AT 1254 PM PDT...WEATHER SERVICE DOPPLER RADAR INDICATED SCATTERED 
THUNDERSTORMS WITH VERY HEAVY RAIN CONTINUING TO DEVELOP OVER THE 
MOUNTAINS AND DESERTS FROM SOUTH OF MOUNT LAGUNA IN SAN DIEGO COUNTY 
TO 10 MILES SOUTHWEST OF PALM SPRINGS. THE STORMS WERE MOVING NORTH 
AT 10 MPH.

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF CREEKS
AND STREAMS...ROADS AND ROADSIDE CULVERTS. THE HEAVY RAINS COULD ALSO
TRIGGER ROCK AND MUDSLIDES IN STEEP TERRAIN.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE. IF YOUR VEHICLE STALLS, ABANDON IT IMMEDIATELY AND SEEK
HIGHER GROUND.

TO REPORT SEVERE WEATHER HAVE THE NEAREST LAW ENFORCEMENT AGENCY
RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE.

$$

LAT...LON 3394 11688 3262 11644 3264 11615 3397 11641

The office that day

Everything else NWS San Diego, CA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 20, 12:27 PM PDTFlash Flood WarningSGXSan Bernardino2 hr
Aug 20, 2:30 PM PDTFlash Flood WarningSGXRiverside, San Bernardino, San Diego2 hr
Aug 20, 3:09 PM PDTSevere Thunderstorm WarningSGXSan Diego51 min

Nearby

Flash Flood Warnings in California, 2003Every flash flood warning in 2003

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.