1 thunderstorm wind, as filed by the National Weather Service.
Every event with a place to put it. 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 Tucson, AZ wrote its last area forecast discussion before the first event at Aug 1, 2:15 AM MST, 35 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 215 AM MST SUN AUG 1 2004 SOUTHEAST ARIZONA FORECAST DISCUSSION .SYNOPSIS...A MOIST FLOW AROUND THE HIGH TO OUR EAST WILL BRING A BETTER CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS THIS WEEK. && .DISCUSSION...WEAK WIGGLE IN SOUTHERLY FLOW HELPED KEEP LIGHT CONVECTION THROUGH SOUTHERN AND CENTRAL ARIZONA OVERNIGHT. DEEPER MOISTURE STARTING TO NOSE BACK IN FROM SONORA...BUT 06Z KTUS SOUNDING STILL RELATIVELY DRY. OUTFLOW FROM NORTHERN SONORA CONVECTION PUSHING UP FROM THE SOUTH...DUG DEWPT JUMPED 20 DEGREES IN 2 HRS WITH 10KTS OUT OF THE SOUTH. A STRONGER IMPULSE WILL PUSH IN FROM THE SOUTH BY MONDAY TO FURTHER ENHANCE SHOWER AND THUNDERSTORM COVERAGE...BACK TO SCATTERED OR BETTER FOR MOST PLACES. WITH INITIAL LOW LEVEL ENVIRONMENT ON THE DRY SIDE...DOWNBURSTS WILL BE A CONCERN. MODELS CONTINUE TO UNDER-DO EXPECTED AVAILABLE MOISTURE WITH THIS PATTERN AS OUTFLOWS FROM ORGANIZED CONVECTION AND POTENTIAL SURGE ACTIVITY BECOME MORE LIKELY. CURRENT FORECAST NEAR CLIMO BY MONDAY AND TUESDAY...THIS TREND STILL LOOKS GOOD. AFTERNOON HIGHS WILL MODERATE AS THIS HAPPENS. NAME IOP#5 WILL CONTINUE THROUGH 00Z MON. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. MEYER
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TUCSON AZ 1200 PM MST SAT JUL 31 2004 AZZ019-029>035-010700- NORTHERN GREENLEE COUNTY-UPPER GILA RIVER VALLEY-COCHISE COUNTY-SOUTHEAST PINAL COUNTY-TUCSON METRO/MARANA/GREEN VALLEY-SANTA CRUZ COUNTY-TOHONO OODHAM NATION-WESTERN PIMA COUNTY- 1200 PM MST SAT JUL 31 2004 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST ARIZONA .DAY ONE...TODAY SYNOPSIS...RELATIVELY DRY AIR RESIDES OVER SOUTHERN ARIZONA. DUE TO THIS AIR MASS ONLY ISOLATED THUNDERSTORMS ARE EXPECTED THIS AFTERNOON. THE MAIN THREAT FROM THESE FEW STORMS WILL BE GUSTY WINDS AND SMALL HAIL. THE PROBABILITY OF HEAVY RAIN IS MUCH LOWER THAN NORMAL FOR THIS TIME OF YEAR. DISCUSSION...MOISTURE RESIDES IN NORTHERN MEXICO ALTHOUGH NO MECHANISM IS PRESENT TO MOVE IT INTO SOUTHERN ARIZONA TODAY. DEBRIS CLOUDINESS WAS PRESENT THIS MORNING WHICH CAN BE SEEN ON 12Z TUS SOUNDING AT 500 MB. THIS LAYER OF MOISTURE WILL DISSIPATE AS SURFACE HEATING MIXES UP THE BOUNDARY LAYER. EXPECT THE 00Z SOUNDING TONIGHT WILL BE SIMILAR TO YESTERDAY EVENING. STRONGER WINDS ALOFT TODAY INCREASES THE POTENTIAL FOR STRONGER WINDS AT THE SURFACE FROM ANY STORMS WHICH OCCUR. ADDITIONALLY THESE WINDS WILL KEEP STORMS MOVING TO REDUCE THE RISK OF LOCALLY HEAVY RAIN OCCURRING. YUMA HAD A JUMP IN DEWPOINT THIS MORNING ASSOCIATED WITH LAST NIGHTS CONVECTION. THIS MOISTURE IS VERY SHALLOW SO EXPECT DEWPOINTS TO DROP ALONG THE LOWER COLORADO RIVER AREA THROUGH THE EARLY EVENING. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH SATURDAY. INCREASING SURFACE TEMPERATURE THE LAST SEVERAL DAYS WILL HELP MOVE THE UPPER LEVEL HIGH PRESSURE TO A MORE FAVORABLE POSITION FOR GETTING MOISTURE INTO ARIZONA. ADDITIONALLY THE FORMATION OF AN INVERTED TROUGH SOUTH OF BAJA AND TROPICAL ACTIVITY OFF THE SOUTHERN MEXICO COAST COULD SET THE STAGE FOR A MAJOR GULF SURGE MID WEEK. GIVEN THESE CHANGES SURFACE MOISTURE SHOULD INCREASE THROUGH THE WEEK...ALONG WITH AN INCREASE IN THUNDERSTORM ACTIVITY. BOTH THE ETA AND GFS MODELS BUILD A THETA E RIDGE OVER SONORA ON MONDAY. THIS RIDGE IS INDICATIVE OF ORGANIZED CONVECTION WHICH WOULD AFFECT LOCATIONS NEAR THE INTERNATIONAL BORDER. BY TUESDAY SPECIFIC DETAILS ARE DIFFICULT TO FIND IN THE MODELS. HOWEVER MOISTURE SHOULD BE PRESENT BY THEN TO CONTINUE A MORE NORMAL AUGUST MONSOON PATTERN...THAT IS...THUNDERSTORMS EVERY DAY. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. GWS
The Tucson radar (KEMX), 43 km away, was scanning. The volume nearest the first event began at 09:49 UTC.
1 thunderstorm wind. Local standard time, as filed.
Strong thunderstorm winds caused the power lines at the 39th block of 16th Avenue to be downed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2004Every state in 2004This day in weather historyWarnings in Arizona, August 2004
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: 5418623.