Alert archive / California / Flash Flood Warnings in 2003

Flash Flood Warning 9, NWS Phoenix, AZ

August 24, 2003Riverside County, California

NWS Phoenix, AZ issued this flash flood warning at Aug 24, 2003, 7:51 AM PDT for Riverside County, California. It was in force for 24 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: Aug 24, 2003, 7:51 AM PDT (14:51 UTC)
Expired: Aug 24, 2003, 8:15 AM PDT
In force: 24 min
Issued by: NWS Phoenix, AZ
Area: Counties, with a storm outline in the text

County Riverside County, CA

The radar

The San Diego radar (KNKX), 165 km from the middle of the area, began a volume at 14:52 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

Yuma Intl Airpor, AZ (KYUM), launched 12:00Z, 2.9 hours before the alert went out and 180 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 141 J/kg
Mixed-layer CIN: -374 J/kg
Mixed-layer LCL: 1626 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 67 m²/s²
0-3 km storm-relative helicity: 130 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 
WGUS55 KPSR 241453
FFWPSR
CAC065-241515-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
751 AM PDT SUN AUG 24 2003

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTH CENTRAL RIVERSIDE COUNTY IN SOUTHEAST CALIFORNIA
  INCLUDING THE JOSHUA TREE NATIONAL PARK

* UNTIL 815 AM PDT

* AT 748 AM PDT...WEATHER SERVICE DOPPLER RADAR INDICATED
  HEAVY RAIN OVER NORTH CENTRAL RIVERSIDE COUNTY...OVER THE
  CENTRAL PORTION OF JOSHUA TREE NATIONAL PARK BETWEEN THE VISITOR
  CENTER AND EAGLE MOUNTAIN.

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. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY. 
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. IF YOUR VEHICLE STALLS...ABANDON IT IMMEDIATELY AND SEEK
HIGHER GROUND.

TO REPORT SEVERE WEATHER HAVE THE NEAREST LAW ENFORCEMENT AGENCY
RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN
PHOENIX.

LAT...LON 3390 11603 3388 11561 3393 11544 3402 11538
          3405 11604

$$

The office that day

Everything else NWS Phoenix, AZ issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 24, 1:32 AM PDT	Severe Thunderstorm Warning	PSR	Imperial	43 min
Aug 24, 6:10 AM PDT	Flash Flood Warning	PSR	Riverside	95 min

Nearby

Flash Flood Warnings in California, 2003 Every flash flood warning in 2003

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.