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 Phoenix, AZ wrote its last area forecast discussion before the first event at Aug 1, 2:50 PM MST, 1 hour 55 minutes earlier.
AZZ020>028-CAZ030>033-020545- SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PHOENIX AZ 250 PM MST WED AUG 1 2001 .SYNOPSIS... THE MAIN HIGH PRESSURE SYSTEM DRIVING THE MONSOON FLOW WILL REMAIN EAST AND NORTHEAST OF ARIZONA THIS WEEK. HOWEVER...IT WILL TEND TO BUILD BACK TOWARDS THE WEST...MOVING THE MONSOON MOISTURE BOUNDARY WESTWARD WITH TIME. AS THIS HAPPENS...IT WILL RESULT IN INCREASING CLOUDINESS OVER SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA...AS WELL AS A GRADUAL UPSWING IN MAINLY AFTERNOON AND NIGHTTIME SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE REGION. .DISCUSSION... MOISTURE COPIOUS. STORMS HAVE BEEN SLOW TO DEVELOP THIS AFTERNOON AS WAS EXPECTED. HOWEVER...SOME NOW IN PROGRESS ON HIGHER TERRAIN AREAS. FLOW HAS TURNED IN ADVANCE OF THE INVERTED TROUGH OVER NM... WITH THE STEERING FLOW NOW BASICALLY OUT OF THE ENE. THIS EXPECTED TO BRING STORMS OFF THE HIGHER TERRAIN TO THE LOWER DESERTS THIS EVENING. MAIN THREAT STILL CONSIDERED TO BE HEAVY RNFL...BUT AS THE STORMS MOVE OFF THE MOUNTAINS...ASSOCIATED WIND GUSTS WILL LIKELY BE ENHANCED DUE TO DOWNSLOPE. STRONG...GUSTY WIND AND BLOWING DUST ARE CONCERNS TO GO ALONG WITH THE HEAVY RNFL. VORT LOBE ASSOCIATED WITH THE INVERTED TROUGH IS EXPECTED TO MOVE NWD THIS EVE AND TONIGHT AS WELL...AND SHOULD ALSO HELP STORMS TO DEVELOP. OUTFLOW BOUNDARIES WILL LIKELY ENTER INTO THE DEVELOPMENT TONIGHT...AS OUTFLOW FROM STORMS OVER SW MARICOPA COUNTY MAY INTERACT WITH OUTFLOW FROM THE STORMS COMING DOWN FROM THE HIGHER TERRAIN N AND E OF THE PHX METRO AREA. FOR THE EXTENDED...WILL KEEP CHANCE WORDING OVER THE ENTIRE CWA...STA RTING SAT...AS MONSOON MOISTURE BOUNDARY AND ITS EMBEDDED IMPULSES EXPECTED TO MOVE WWD ENCOMPASSING THE ENTIRE CWA SAT THRU WED. WILT
The Phoenix radar (KIWA), 77 km away, was scanning. The volume nearest the first event began at 23:45 UTC.
1 flash flood. Local standard time, as filed.
Thunderstorms with heavy rainfall, of up to one inch per hour, caused flash flooding of washes and streets in the town.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2001Every state in 2001This day in weather historyWarnings in Arizona, August 2001
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: 5262818.