Alert archive / California / Flash Flood Warnings in 2012

Flash Flood Warning 14, NWS San Diego, CA

August 12, 2012San Diego County, California

NWS San Diego, CA issued this flash flood warning at Aug 12, 2012, 5:53 PM PDT for San Diego County, California. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 12, 2012, 5:53 PM PDT (00:53 UTC)
Expired
Aug 12, 2012, 8:45 PM PDT
In force
3 hr
Issued by
NWS San Diego, CA
Area
Storm-based polygon
Flood severity
None

County San Diego County, CA

The radar

The San Diego radar (KNKX), 74 km from the middle of the area, began a volume at 00:53 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 00:00Z, 0.9 hours before the alert went out and 91 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 00:00Z on 2012-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 142 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 00:00Z on 2012-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 32 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
142 J/kg
Mixed-layer CIN
-559 J/kg
Mixed-layer LCL
2368 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
32 m²/s²
0-3 km storm-relative helicity
58 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.

988 
WGUS56 KSGX 130053
FFWSGX
CAC073-130345-
/O.NEW.KSGX.FF.W.0014.120813T0053Z-120813T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN DIEGO CA
553 PM PDT SUN AUG 12 2012

THE NATIONAL WEATHER SERVICE IN SAN DIEGO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EAST CENTRAL SAN DIEGO COUNTY IN SOUTHWEST CALIFORNIA...

* UNTIL 845 PM PDT

* AT 542 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  VERY HEAVY RAIN FROM A THUNDERSTORM OVER THE EASTERN SAN DIEGO     
  COUNTY DESERTS. THIS STORM IS CAPABLE OF PRODUCING FLASH FLOODING  
  OVER THE WARNED AREA.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO OCOTILLO   
WELLS...SHELTER VALLEY...AGUA CALIENTE SPRINGS AND CANEBRAKE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 3294 11642 3301 11647 3316 11644 3318 11607
      3308 11607 3307 11609 3284 11610

$$

JJT/JT
3 follow-up statements
496 
WGUS76 KSGX 130152
FFSSGX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SAN DIEGO CA
652 PM PDT SUN AUG 12 2012

CAC073-130345-
/O.CON.KSGX.FF.W.0014.000000T0000Z-120813T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN DIEGO CA-
652 PM PDT SUN AUG 12 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 845 PM PDT FOR EAST
CENTRAL SAN DIEGO COUNTY...

AT 630 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE HEAVY RAIN FROM A THUNDERSTORM OVER THE WARNED AREA. RADAR 
ESTIMATED STORM TOTAL PRECIPITATION AMOUNTS SO FAR RANGE FROM ONE 
AND A HALF TO TWO INCHES IN THE LAST HOUR AND A HALF.    

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO OCOTILLO 
WELLS...AGUA CALIENTE SPRINGS...SOUTH OF CALIFORNIA HIGHWAY 78 
BETWEEN ROUTE S2 AND THE IMPERIAL COUNTY BOARDER. WASHES AFFECTED 
INCLUDE FISH CREEK WASH AND VALLECITO CREEK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 3294 11642 3301 11647 3316 11644 3318 11607
      3308 11607 3307 11609 3284 11610

$$

JT/JJT
606 
WGUS76 KSGX 130316
FFSSGX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SAN DIEGO CA
816 PM PDT SUN AUG 12 2012

CAC073-130345-
/O.CON.KSGX.FF.W.0014.000000T0000Z-120813T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN DIEGO CA-
816 PM PDT SUN AUG 12 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 845 PM PDT FOR EAST
CENTRAL SAN DIEGO COUNTY...

AT 754 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
THAT THUNDERSTORMS HAVE DISSIPATED OVER THE WARNED AREA. RADAR 
ESTIMATED STORM TOTAL PRECIPITATION AMOUNTS ARE AS HIGH AS TWO 
INCHES IN SOME LOCATIONS OVER THE PAST THREE HOURS. ALTHOUGH 
PRECIPITATION HAS CURRENTLY ENDED...WATER DRAINING FROM HIGHER TO 
LOWER LOCATIONS IS STILL POSSIBLE OVER THE WARNED AREA THROUGH 845 
PM PDT.  

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO OCOTILLO 
WELLS...AGUA CALIENTE SPRINGS...SOUTH OF CALIFORNIA HIGHWAY 78 
BETWEEN ROUTE S2 AND THE IMPERIAL COUNTY BOARDER. WASHES AFFECTED 
INCLUDE FISH CREEK WASH AND VALLECITO CREEK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVE
UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS
SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 3294 11642 3301 11647 3316 11644 3318 11607
      3308 11607 3307 11609 3284 11610

$$

JJT
626 
WGUS76 KSGX 130339
FFSSGX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SAN DIEGO CA
839 PM PDT SUN AUG 12 2012

CAC073-130348-
/O.EXP.KSGX.FF.W.0014.000000T0000Z-120813T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN DIEGO CA-
839 PM PDT SUN AUG 12 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 845 PM PDT FOR EAST CENTRAL
SAN DIEGO COUNTY...

FLOODING IS NO LONGER EXPECTED FOR THE WARNED AREA. THEREFORE...THE 
FLASH FLOOD WARNING FOR EAST CENTRAL SAN DIEGO COUNTY WILL BE 
ALLOWED TO EXPIRE AT 845 PM PDT.

LAT...LON 3294 11642 3301 11647 3316 11644 3318 11607
      3308 11607 3307 11609 3284 11610

$$

JJT

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 12, 5:29 PM PDTSevere Thunderstorm WarningSGXSan Diego46 min
Aug 12, 6:14 PM PDTSevere Thunderstorm WarningSGXSan Diego46 min
Aug 12, 7:23 PM PDTAreal Flood AdvisorySGXRiverside, San Diego112 min
Aug 13, 3:23 AM PDTFlash Flood WatchSGXRiverside, San Bernardino, San Diego16 hr
Aug 13, 11:43 AM PDTSpecial Weather StatementSGX47 min
Aug 13, 11:54 AM PDTAreal Flood AdvisorySGXSan Bernardino65 min
Aug 13, 12:19 PM PDTFlash Flood WarningSGXSan Diego2 hr
Aug 13, 12:28 PM PDTSpecial Weather StatementSGXSan Diego62 min
Aug 13, 12:35 PM PDTFlash Flood WarningSGXSan Diego2 hr
Aug 13, 12:58 PM PDTAreal Flood AdvisorySGXRiverside, San Bernardino3 hr
Aug 13, 1:22 PM PDTSpecial Weather StatementSGXSan Diego53 min
Aug 13, 1:31 PM PDTFlash Flood WarningSGXRiverside, San Diego2 hr
Aug 13, 1:37 PM PDTFlash Flood WarningSGXSan Bernardino3 hr
Aug 13, 3:06 PM PDTAreal Flood AdvisorySGXRiverside, San Bernardino97 min

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.