Alert archive / California / Flash Flood Warnings in 2012

Flash Flood Warning 36, NWS San Diego, CA

August 30, 2012Riverside County, California

NWS San Diego, CA issued this flash flood warning at Aug 30, 2012, 2:31 PM PDT for Riverside County, California. It was in force for 119 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 30, 2012, 2:31 PM PDT (21:31 UTC)
Expired
Aug 30, 2012, 4:30 PM PDT
In force
119 min
Issued by
NWS San Diego, CA
Area
Storm-based polygon
Flood severity
None

County Riverside County, CA

What was reported inside it

TimeReportWhereRemark
Aug 30, 3:27 PM PDTFLOODMoreno Valley, CAEASTBOUND HIGHWAY 60 AT REDLANDS BLVD CLOSED DUE TO FLOODING.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

San Diego, CA (KNKX), launched 12:00Z, 9.5 hours before the alert went out and 121 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 2012-08-30Temperature 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 2012-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 13 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
2209 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
13 m²/s²
0-3 km storm-relative helicity
73 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.

072 
WGUS56 KSGX 302131
FFWSGX
CAC065-302330-
/O.NEW.KSGX.FF.W.0036.120830T2131Z-120830T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN DIEGO CA
231 PM PDT THU AUG 30 2012

THE NATIONAL WEATHER SERVICE IN SAN DIEGO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  WEST CENTRAL RIVERSIDE COUNTY IN SOUTHERN CALIFORNIA...
  THIS INCLUDES THE CITY OF MORENO VALLEY...

* UNTIL 430 PM PDT

* AT 224 PM PDT...A THUNDERSTORM WITH VERY HEAVY RAIN CONTINUED NEAR 
MORENO VALLEY. OTHER THUNDERSTORMS WITH HEAVY RAIN ARE DEVELOPING 
NEAR MORENO VALLEY AND WEST OF PERRIS...WHICH WILL LIKELY PRODUCE 
FLOODING AFTER 300 PM.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO MORENO 
VALLEY...MARCH AIR FORCE BASE...LAKEVIEW AND PERRIS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3400 11734 3400 11702 3375 11695 3367 11741

$$

MAXWELL
2 follow-up statements
447 
WGUS76 KSGX 302222
FFSSGX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SAN DIEGO CA
322 PM PDT THU AUG 30 2012

CAC065-302330-
/O.CON.KSGX.FF.W.0036.000000T0000Z-120830T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
RIVERSIDE CA-
322 PM PDT THU AUG 30 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 430 PM PDT FOR WEST
CENTRAL RIVERSIDE COUNTY...

AT 312 PM PDT...HEAVY RAIN CONTINUED FROM THE EAST SIDE OF RIVERSIDE 
TO MORENO VALLEY AND SOUTH TO PERRIS AND SUN CITY. FLASH FLOODING 
WAS REPORTED IN SAN TIMOTEO CANYON BETWEEN REDLANDS AND MORENO 
VALLEY WITH CARS STUCK IN FLOOD WATERS ALONG SAN TIMOTEO CANYON ROAD.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO MORENO 
VALLEY...MARCH FIELD...NUEVO...LAKEVIEW...PERRIS AND SUN CITY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLOODING IS OCCURRING OR IS IMMINENT. MOST FLOOD RELATED DEATHS OCCUR
IN AUTOMOBILES. DO NOT ATTEMPT TO CROSS WATER COVERED BRIDGES...
DIPS...OR LOW WATER CROSSINGS. NEVER TRY TO CROSS A FLOWING STREAM...
EVEN A SMALL ONE...ON FOOT. TO ESCAPE RISING WATER MOVE UP TO HIGHER
GROUND.

&&

LAT...LON 3400 11734 3400 11702 3375 11695 3367 11741

$$

MAXWELL
526 
WGUS76 KSGX 302329
FFSSGX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SAN DIEGO CA
429 PM PDT THU AUG 30 2012

CAC065-302338-
/O.EXP.KSGX.FF.W.0036.000000T0000Z-120830T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
RIVERSIDE CA-
429 PM PDT THU AUG 30 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 430 PM PDT FOR WEST CENTRAL
RIVERSIDE COUNTY...

MOST OF THE PRECIPITATION HAD BECOME LIGHT...AND NO FURTHER FLASH 
FLOODING IS EXPECTED IN THE INLAND EMPIRE THIS AFTERNOON. 
HOWEVER...SOME PONDING OF WATER WILL CONTINUE ON ROADWAYS FROM 
PREVIOUS HEAVY RAINS THROUGH ABOUT 500 PM...INCLUDING NEAR LAKE 
ELSINORE AND SUN CITY.

LAT...LON 3400 11734 3400 11702 3375 11695 3367 11741

$$

MAXWELL

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 29, 8:47 PM PDTHigh Surf AdvisorySGXSan Diego4 days
Aug 30, 3:18 AM PDTFlash Flood WatchSGXRiverside, San Bernardino, San Diego16 hr
Aug 30, 11:57 AM PDTFlash Flood WarningSGXRiverside, San Bernardino2 hr
Aug 30, 12:04 PM PDTAreal Flood AdvisorySGXSan Diego116 min
Aug 30, 12:11 PM PDTFlash Flood WarningSGXSan Diego3 hr
Aug 30, 12:11 PM PDTSevere Thunderstorm WarningSGXSan Diego34 min
Aug 30, 12:18 PM PDTSevere Thunderstorm WarningSGXSan Diego57 min
Aug 30, 12:45 PM PDTFlash Flood WarningSGXRiverside3 hr
Aug 30, 12:50 PM PDTSpecial Weather StatementSGXSan Diego55 min
Aug 30, 1:05 PM PDTFlash Flood WarningSGXSan Bernardino3 hr
Aug 30, 1:30 PM PDTAreal Flood AdvisorySGXRiverside, San Bernardino, San Diego3 hr
Aug 30, 1:52 PM PDTSevere Thunderstorm WarningSGXRiverside, San Bernardino53 min
Aug 30, 1:58 PM PDTFlash Flood WarningSGXSan Bernardino2 hr
Aug 30, 2:38 PM PDTAreal Flood AdvisorySGXSan Bernardino40 min
Aug 30, 2:45 PM PDTSevere Thunderstorm WarningSGXRiverside60 min
Aug 30, 3:10 PM PDTFlash Flood WarningSGXSan Bernardino2 hr

Nearby

Flash Flood Warnings in California, 2012Every flash flood warning in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive.