Alert archive / California / Flash Flood Warnings in 2012

Flash Flood Warning 6, NWS San Diego, CA

July 30, 2012San Diego County, California

NWS San Diego, CA issued this flash flood warning at Jul 30, 2012, 2:54 PM PDT for San Diego County, California. It was in force for 111 min. 2 reports 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
Jul 30, 2012, 2:54 PM PDT (21:54 UTC)
Expired
Jul 30, 2012, 4:45 PM PDT
In force
111 min
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), 48 km from the middle of the area, began a volume at 21:57 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.

What was reported inside it

TimeReportWhereRemark
Jul 30, 3:34 PM PDTHEAVY RAIN 1.1610 E Julian, CARAINFALL OCCURRED IN SHELTER VALLEY IN 15 MINUTES...AND CREATED 2 FEET OF STANDING WATER IN A BACKYARD.
Jul 30, 3:38 PM PDTFLASH FLOOD10 E Julian, CAFLASH FLOOD AND MUD/ROCK SLIDE OVER COUNTY ROAD S2 IN SHELTER VALLEY.

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, 9.9 hours before the alert went out and 67 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 2012-07-30Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, San Diego, CA at 12:00Z on 2012-07-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -18 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
1583 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
-18 m²/s²
0-3 km storm-relative helicity
7 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.

633 
WGUS56 KSGX 302154
FFWSGX
CAC073-302345-
/O.NEW.KSGX.FF.W.0006.120730T2154Z-120730T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN DIEGO CA
254 PM PDT MON JUL 30 2012

THE NATIONAL WEATHER SERVICE IN SAN DIEGO HAS ISSUED A

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

* UNTIL 445 PM PDT

* AT 248 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  FLASH FLOODING FROM A STORM OVER THE WARNED AREA. RADAR ESTIMATED  
  RAINFALL RATES RANGE FROM 1 TO 1.50 INCHES OVER THE PAST HOUR.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO JULIAN

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 3307 11667 3318 11663 3317 11643 3307 11640
      3294 11645 3295 11666

$$

TAEGER/PALMER
3 follow-up statements
185 
WGUS76 KSGX 302226
FFSSGX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SAN DIEGO CA
326 PM PDT MON JUL 30 2012

CAC073-302345-
/O.CON.KSGX.FF.W.0006.000000T0000Z-120730T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN DIEGO CA-
326 PM PDT MON JUL 30 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 445 PM PDT FOR
CENTRAL SAN DIEGO COUNTY...

AT 318 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE HEAVY RAIN PRODUCING FLASH FLOODING OVER THE WARNED AREA. 
RADAR RAINFALL ESTIMATES RANGE FROM 1.25 TO 1.75 INCHES IN THE LAST 
HOUR. HOWEVER...SIMILAR STORMS NEARBY HAVE PRODUCED UP TO 2 INCHES 
IN THE LAST HOUR...AND HEAVIER RAINFALL COULD BE OCCURRING.  

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO JULIAN

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.

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.

&&

LAT...LON 3307 11667 3318 11663 3317 11643 3307 11640
      3294 11645 3295 11666

$$

TAEGER/PALMER
364 
WGUS76 KSGX 302307
FFSSGX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SAN DIEGO CA
407 PM PDT MON JUL 30 2012

CAC073-302345-
/O.CON.KSGX.FF.W.0006.000000T0000Z-120730T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN DIEGO CA-
407 PM PDT MON JUL 30 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 445 PM PDT FOR
CENTRAL SAN DIEGO COUNTY...

AT 400 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE HEAVY RAIN PRODUCING FLASH FLOODING OVER THE WARNED 
AREA...WITH ONE HOUR RAINFALL RATES RANGING BETWEEN 1.5 AND 3 INCHES 
JUST SOUTH OF SHELTER VALLEY.  A STORM SPOTTER IN THE SHELTER VALLEY 
AREA ALSO REPORTED 1.16 INCHES OF RAINFALL IN 15 MINUTES...WITH 2 
FEET OF STANDING WATER IN HIS BACKYARD.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO JULIAN AND 
SHELTER VALLEY

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 3307 11667 3318 11663 3317 11643 3307 11640
      3294 11645 3295 11666

$$

PALMER/TAEGER
265 
WGUS76 KSGX 302345
FFSSGX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SAN DIEGO CA
445 PM PDT MON JUL 30 2012

CAC073-302354-
/O.EXP.KSGX.FF.W.0006.000000T0000Z-120730T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SAN DIEGO CA-
445 PM PDT MON JUL 30 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 445 PM PDT FOR CENTRAL SAN
DIEGO COUNTY...

STORMS HAVE WEAKENED OVER THE WARNED AREA...BUT LIGHT RAIN IS STILL 
POSSIBLE. THEREFORE...THE FLASH FLOOD WARNING WILL EXPIRE AT 445 PM 
PDT.

LAT...LON 3307 11667 3318 11663 3317 11643 3307 11640
      3294 11645 3295 11666

$$

TAEGER/PALMER

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 30, 10:55 AM PDTFlash Flood WatchSGXRiverside, San Diego9 hr
Jul 30, 2:11 PM PDTFlash Flood WarningSGXSan Diego64 min
Jul 30, 3:09 PM PDTSevere Thunderstorm WarningSGXSan Diego51 min
Jul 30, 3:59 PM PDTFlash Flood WarningSGXSan Diego2 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; radar from the NEXRAD Level II archive.