Alert archive / California / Flash Flood Warnings in 2005

Flash Flood Warning 21, NWS San Diego, CA

February 21, 2005Riverside County, San Bernardino County, San Diego County, California

NWS San Diego, CA issued this flash flood warning at Feb 21, 2005, 7:45 AM PST for Riverside County, San Bernardino County, San Diego County, California. It was in force for 2 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
Feb 21, 2005, 7:45 AM PST (15:45 UTC)
Expired
Feb 21, 2005, 10:00 AM PST
In force
2 hr
Issued by
NWS San Diego, CA
Area
Whole counties

Counties Riverside County, CA, San Bernardino County, CA, San Diego County, CA

The radar

The Santa Ana Mts radar (KSOX), 122 km from the middle of the area, began a volume at 15:48 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, 3.8 hours before the alert went out and 145 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 2005-02-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2 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, San Diego, CA at 12:00Z on 2005-02-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 243 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
2 J/kg
Mixed-layer CIN
-9 J/kg
Mixed-layer LCL
645 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
243 m²/s²
0-3 km storm-relative helicity
275 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 211543
FFWSGX
CAC065-071-073-211800-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN DIEGO CA
745 AM PST MON FEB 21 2005

THE NATIONAL WEATHER SERVICE IN SAN DIEGO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  WESTERN RIVERSIDE COUNTY IN SOUTHEAST CALIFORNIA
  SOUTHWESTERN SAN BERNARDINO COUNTY IN SOUTHEAST CALIFORNIA         
  SAN DIEGO COUNTY IN SOUTHWEST CALIFORNIA

* UNTIL 1000 AM PST

* THROUGH 10 AM...NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS WITH 
MODERATE TO HEAVY RAINFALL WILL MOVE ONSHORE ACROSS SOUTHWEST 
CALIFORNIA. FLASH FLOODING IS POSSIBLE IN LOW LYING AREAS ALONG AND 
WEST OF THE MOUNTAINS IN SOUTHWEST SAN BERNARDINO...WESTERN 
RIVERSIDE...AND SAN DIEGO COUNTIES. MOVEMENT OF THE SHOWERS AND 
THUNDESTORMS IS TO THE NORTHEAST AT 35 MPH. HOURLY RAINFALL OF ONE 
HALF TO ONE INCH PER HOUR IS POSSIBLE. OVER SAN DIEGO COUNTY... 
HEAVIEST RAINFALL THROUGH 9 AM WILL BE OVER NORTHERN AND CENTRAL 
PORTIONS OF THE COUNTY.

MUD SLIDES AND ROCK SLIDES ARE POSSIBLE IN STEEP TERRAIN. MUD SLIDES 
AND ROCK SLIDES CAN POTENTIALLY TRAP AND KILL PEOPLE CAUGHT IN THEIR 
PATH.

RESIDENTS AND MOTORISTS IN AND BELOW RECENTLY BURNED AREAS SHOULD BE
ALERT TO HEAVY MUD AND DEBRIS FLOWS WHICH MAY BLOCK ROADS AND
CULVERTS. POTENTIALLY DANGEROUS FLOODING AND PROPERTY LOSS COULD
RESULT IN AREAS WHERE RUNOFF IS RESTRICTED OR BLOCKED.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES
AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

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. MOVE TO HIGHER GROUND.

$$

MARTIN

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 21, 6:45 AM PSTFlash Flood WarningSGXOrange2 hr
Feb 21, 7:03 AM PSTSpecial Marine WarningSGX117 min
Feb 21, 7:57 AM PSTTornado WarningSGXOrange33 min
Feb 21, 8:54 AM PSTFlash Flood WarningSGXOrange66 min
Feb 21, 9:06 AM PSTSpecial Marine WarningSGX114 min
Feb 21, 9:56 AM PSTFlash Flood WarningSGXOrange, Riverside, San Bernardino, San Diego3 hr
Feb 21, 12:34 PM PSTFlash Flood WarningSGXOrange, Riverside, San Bernardino, San Diego3 hr

Nearby

Flash Flood Warnings in California, 2005Every flash flood warning in 2005

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.