Alert archive / California / Flash Flood Warnings in 2004

Flash Flood Warning 82, NWS San Diego, CA

October 20, 2004San Bernardino County, California

NWS San Diego, CA issued this flash flood warning at Oct 20, 2004, 6:39 PM PDT for San Bernardino County, California. It was in force for 111 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Oct 20, 2004, 6:39 PM PDT (01:39 UTC)
Expired
Oct 20, 2004, 8:30 PM PDT
In force
111 min
Issued by
NWS San Diego, CA
Area
Counties, with a storm outline in the text

County San Bernardino County, CA

The radar

The Santa Ana Mts radar (KSOX), 34 km from the middle of the area, began a volume at 01:42 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, 1.7 hours before the alert went out and 152 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 2004-10-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2004-10-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -149 square meters per square second.1939587897117136Sfc1 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
1 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
563 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
-149 m²/s²
0-3 km storm-relative helicity
-96 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 210141
FFWSGX
CAC071-210330-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN DIEGO CA
639 PM PDT WED OCT 20 2004

THE NATIONAL WEATHER SERVICE IN SAN DIEGO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHWESTERN SAN BERNARDINO COUNTY IN SOUTHEAST CALIFORNIA
  THIS INCLUDES THE CITIES OF...UPLAND...RANCHO CUCAMONGA...
  ONTARIO...MONTCLAIR...FONTANA...CHINO HILLS...CHINO

* UNTIL 830 PM PDT

* AT 635 PM PDT...FLASH FLOODING WAS REPORTED FROM HEAVY RAIN
  NEAR RANCHO CUCAMONGA. THAT AREA OF RAIN WAS MOVING NORTHEAST AT
  25 MPH. OTHER HEAVY RAIN CAPABLE OF PRODUCING FLASH FLOODING
  EXTENDED FROM 5 MILES SOUTHWEST OF THE CAJON PASS TO DEVORE TO
  RIALTO TO ONTARIO.

LOCAL RAINFALL RATES OF UP TO ONE INCH PER HOUR WILL BE POSSIBLE 
WITH THIS STORM OVER THE FOOTHILLS.

MUD SLIDES AND ROCK SLIDES ARE EXPECTED WITH THIS STORM...ESPECIALLY 
NEAR THE FIRE BURN AREAS NEAR DEVORE AND LYTLE CREEK. MUD SLIDES AND 
ROCK SLIDES CAN POTENTIALLY TRAP AND KILL PEOPLE CAUGHT IN THEIR 
PATH.

LAT...LON 3398 11777 3394 11769 3419 11730 3441 11749
      3426 11764

$$

MAXWELL

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 21, 9:25 AM PDTSpecial Marine WarningSGX65 min

Nearby

Flash Flood Warnings in California, 2004Every flash flood warning in 2004

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.