1 flash flood, as filed by the National Weather Service.
Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Las Vegas, NV wrote its last area forecast discussion before the first event at Aug 1, 9:30 AM PST, 4 hours 55 minutes earlier.
MOJAVE DESERT/SOUTHERN GREAT BASIN AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LAS VEGAS NV 1030 AM PDT FRI AUG 1 2003 .SYNOPSIS...A MOIST SOUTHEAST FLOW ACROSS THE SOUTHERN GREAT BASIN AND MOJAVE DESERT WILL CONTINUE TO FEED SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS THROUGH SATURDAY. LOCALLY HEAVY RAIN AND FLASH FLOODING ARE POSSIBLE THIS AFTERNOON AND EVENING. SLIGHTLY DRIER AIR WILL START TO MOVE IN FROM THE SOUTHWEST SUNDAY AND INTO EARLY NEXT WEEK FOR A DECREASE IN THUNDERSTORM COVERAGE. TEMPERATURES ARE EXPECTED TO REMAIN SLIGHTLY BELOW NORMAL. .SHORT TERM...MOISTURE CONTINUES TO STREAM INTO AREA IN SOUTHEAST FLOW BETWEEN NEGATIVE TILTED WEAK TROUGH ALONG THE CALIFORNIA COAST AND RIDGE OFF TO OUR EAST. SATELLITE IMAGERY SHOWS EXTENSIVE CLOUD COVER ACROSS THE FORECAST AREA THIS MORNING WITH SHORTWAVE EMBEDDED IN SOUTHEAST FLOW BETWEEN KINGMAN AND PHOENIX. RADAR SHOWS LARGE AREA OF LIGHT RAIN ACROSS EASTERN SAN BERNARDINO AND SOUTHERN MOHAVE COUNTIES SLOWLY SHIFTING NORTHWARD. ONLY GETTING AN INFREQUENT LIGHTNING STRIKE OUT OF THE AREA. CONCERN TODAY IS WILL THIS EXTENSIVE AREA OF CLOUDS/SHOWERS INHIBIT SURFACE HEATING ENOUGH TO INHIBIT THUNDERSTORMS? AIR MASS IS PRIMED WITH PRECIPITABLE WATER VALUES STILL BETWEEN 1 AND 1.5 INCHES AND REGION PROGGED TO STAY UNDER AREA OF DIVERGENCE ALOFT ASSOCIATED WITH 40-50 KNOT JET OVER AREA. PRESENTLY.... NORTHERN NYE AND LINCOLN COUNTIES ONLY AREA IN CWA NOT UNDER OVERCAST. ALSO STARTING TO SEE MORE BREAKS IN THE CLOUDS ACROSS SOUTHERN AND CENTRAL ARIZONA AS SHORTWAVE LIFTS NORTHWEST. EXPECT TO SEE FIRST DEVELOPMENT DUE TO DIFFERENTIAL HEATING AROUND EDGE OF OVERCAST WITH EYES MONITORING CENTRAL AND SOUTHERN ARIZONA THROUGHOUT THE DAY. FLASH FLOOD WATCH WILL STAY POSTED FOR ALL ZONES AND WILL TAKE ANOTHER LOOK AT WATCH IN AFTERNOON PACKAGE. OTHER CONCERN IS THE HIGH TEMPERATURES DUE TO CLOUDS AND SHOWERS AND WILL UPDATE SHORTLY. .LAS...FLASH FLOOD WATCH THROUGH 9 PM ALL ZONES. PIERCE
AZZ001>003-036-CAZ026>029-NVZ013>022-021400- HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE LAS VEGAS NV 500 AM PDT FRI AUG 1 2003 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST CALIFORNIA/SOUTHERN NEVADA/NORTHWEST ARIZONA .DAY ONE...TODAY. A FLASH FLOOD WATCH IS IN EFFECT FOR SOUTHEAST CALIFORNIA...SOUTHERN NEVADA...AND NORTHWEST ARIZONA UNTIL 9 PM THIS EVENING. SHOWERS WERE INCREASING IN COVERAGE AND MOVING NORTHWEST THROUGH SOUTHEAST CALIFORNIA AND NORTHWEST ARIZONA THIS MORNING. BY THIS AFTERNOON...THUNDERSTORMS WILL DEVELOP...AND MAY PRODUCE HEAVY RAINFALL. ALTHOUGH HEAVY RAINFALL WILL NOT OCCUR EVERYWHERE...ANY LOCATION THAT GETS A THUNDERSTORM COULD SEE ONE TO TWO INCHES OF RAIN IN A SHORT TIME...RESULTING IN FLASH FLOODING. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. THUNDERSTORM COVERAGE IS EXPECTED TO DECREASE ON SATURDAY AND SUNDAY AS STRONGER FORCING MOVES AWAY FROM THE AREA. FOR MONDAY THROUGH THURSDAY...IT APPEARS AT THIS TIME THAT THE AIRMASS WILL DRY OUT ENOUGH TO PREVENT THUNDERSTORM DEVELOPMENT...ALTHOUGH THIS IS UNCERTAIN.
The national radar mosaic for the moment the first event began.
1 flash flood. Local standard time, as filed.
A stationary thunderstorms produced an estimated two and a half inches of rain just south of Twentynine Palms. Spotters reported two feet of water in local washes along with water running across roads making them impassable.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2003Every state in 2003This day in weather historyWarnings in California, August 2003
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5378063.