Alert archive / California / Flash Flood Warnings in 2007

Flash Flood Warning 21, NWS San Diego, CA

August 30, 2007Riverside County, California

NWS San Diego, CA issued this flash flood warning at Aug 30, 2007, 3:13 PM PDT for Riverside County, California. It took effect at Aug 30, 2007, 3:18 PM PDT. It was in force for 57 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 30, 2007, 3:13 PM PDT (22:13 UTC)
In effect from
Aug 30, 2007, 3:18 PM PDT
Expired
Aug 30, 2007, 4:15 PM PDT
In force
57 min
Issued by
NWS San Diego, CA
Area
Whole counties

County Riverside County, CA

The radar

The San Diego radar (KNKX), 134 km from the middle of the area, began a volume at 22:16 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, 10.2 hours before the alert went out and 154 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 2007-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 215 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 2007-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 61 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
215 J/kg
Mixed-layer CIN
-775 J/kg
Mixed-layer LCL
1630 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
61 m²/s²
0-3 km storm-relative helicity
122 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 302218
FFWSGX
CAC065-302315-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN DIEGO CA
313 PM PDT THU AUG 30 2007

THE NATIONAL WEATHER SERVICE IN SAN DIEGO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHWESTERN RIVERSIDE COUNTY

* UNTIL 415 PM PDT

* AT 306 PM PDT...FLASH FLOODING WAS OCCURRING OVER THE TOWN OF       
  AGUANGA AND ALONG HIGHWAY 371 WEST OF ANZA. 

* LOCATIONS IN THE WARNING INCLUDE AGUANGA. FLOODING AND DEBRIS      
  FLOWS ARE LIKELY ALONG SECTIONS OF HIGHWAY 371 WEST OF ANZA.

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.

LAT...LON 3358 11701 3368 11684 3351 11669 3343 11686
TIME...MOT...LOC 2213Z 180DEG 0KT 3352 11681

$$

MOEDE
2 follow-up statements
000 
WGUS76 KSGX 302236
FFSSGX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SAN DIEGO CA
332 PM PDT THU AUG 30 2007

CAC065-302315-
RIVERSIDE CA-
332 PM PDT THU AUG 30 2007

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 415 PM PDT FOR
SOUTHWESTERN RIVERSIDE COUNTY...

AT 324 PM PDT...A THUNDERSTORM PRODUCING FLASH FLOODING WAS REPORTED 
5 MILES NORTH OF AGUANGA. THE STORM WAS WEAKENING AS IT MOVED NORTH 
AT 10 MPH. 

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL 
CREEKS AND STREAMS....AS WELL AS SECTIONS OF HIGHWAY 371 BETWEEN 
AGUANGA AND ANZA. 

LAT...LON 3358 11701 3368 11684 3351 11669 3343 11686
TIME...MOT...LOC 2232Z 180DEG 0KT 3352 11681

$$

MOEDE
000 
WGUS76 KSGX 302245
FFSSGX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SAN DIEGO CA
343 PM PDT THU AUG 30 2007

CAC065-302253-
RIVERSIDE CA-
343 PM PDT THU AUG 30 2007

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR SOUTHWESTERN
RIVERSIDE COUNTY...

THE THUNDERSTORM THAT BROUGHT FLASH FLOODING TO AGUANGA AND HIGHWAY 
371 IN THE SOUTHERN RIVERSIDE COUNTY MOUNTAINS HAS DECREASED IN 
INTENSITY. 

LAT...LON 3358 11701 3368 11684 3351 11669 3343 11686
TIME...MOT...LOC 2243Z 180DEG 0KT 3352 11681

$$

MOEDE

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 30, 3:13 AM PDTMarine Weather StatementSGX6 hr
Aug 30, 3:25 AM PDTExcessive Heat WarningSGXRiverside, San Bernardino, San Diego15 hr
Aug 30, 4:55 AM PDTFlash Flood WatchSGXRiverside, San Bernardino, San Diego14 hr
Aug 30, 1:16 PM PDTSevere Thunderstorm WarningSGXSan Diego57 min
Aug 30, 2:46 PM PDTSevere Thunderstorm WarningSGXRiverside59 min
Aug 30, 3:58 PM PDTFlash Flood WarningSGXSan Diego62 min
Aug 30, 4:28 PM PDTSevere Thunderstorm WarningSGXSan Bernardino48 min
Aug 30, 4:40 PM PDTFlash Flood WarningSGXSan Bernardino2 hr

Nearby

Flash Flood Warnings in California, 2007Every flash flood warning in 2007

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.