A weak upper level disturbance combined with abundant moisture approaching 2 inches of precipitable water to generate widespread thunderstorms across southeast Arizona. Thunderstorms produced flash flooding and some produced damaging winds.
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 episode as NWS TWC wrote it up.
A weak upper level disturbance combined with abundant moisture approaching 2 inches of precipitable water to generate widespread thunderstorms across southeast Arizona. Thunderstorms produced flash flooding and some produced damaging winds. The heavy rain caused flooding of the Brawley Wash on the west side of Tucson during the predawn hours of September 7th. One fatality and one injury resulted.
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 Sep 6, 2:10 PM MST, 27 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 210 PM MST THU SEP 6 2012 .SYNOPSIS...ABUNDANT MOISTURE WILL RESULT IN SCATTERED THUNDERSTORMS INTO EARLY NEXT WEEK. EXPECT HEAVY RAINFALL WITH THE STRONGER THUNDERSTORMS. DAYTIME TEMPERATURES WILL GENERALLY BE A FEW DEGREES BELOW NORMAL. && .DISCUSSION...SCATTERED TO NUMEROUS THUNDERSTORMS PRODUCING HEAVY RAINFALL ONGOING AT THIS TIME. HAVE DEPICTED HEAVY RAINFALL MOST SECTIONS THRU THIS EVENING IN THE GRIDDED DATA WEATHER FIELD AND VARIOUS TEXT PRODUCTS. STRONG THUNDERSTORM OUTFLOW MAY BE GENERATED LEADING TO AREAS OF BLOWING DUST AND REDUCED VISIBILITIES INTO EARLY THIS EVENING FROM JUST NW OF TUCSON INTO SOUTH CENTRAL PINAL COUNTY. VARIOUS NWP MESOSCALE MODELS INDICATE THAT BULK OF PRECIP WILL DECREASE IN COVERAGE LATE TONIGHT. ABUNDANT MOISTURE STILL MERITS A SLIGHT CHANCE OF SHOWERS/TSTMS LATE TONIGHT INTO EARLY FRI MORNING. FRI-TUE... HIGH PRESSURE ALOFT OVER THE SWRN CONUS THRU SAT THEN UPPER RIDGE TO WEAKEN AS SERIES OF UPPER LEVEL IMPULSES APPROACH FROM THE WEST. 06/12Z GFS/ECMWF MAINTAIN AMPLE MOISTURE TO SUPPORT SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS/TSTMS THIS PERIOD. WED-THUR... PRECIP CHANCES TO TREND DOWNWARD AS THE BULK OF DEEPER MOISTURE IS PROGGED TO MOVE EAST OF THE AREA. HAVE OPTED FOR A SLIGHT CHANCE OF AFTERNOON AND EVENING SHOWERS/TSTMS. HIGH TEMPS THIS FORECAST PERIOD TO AVERAGE A FEW DEGS BELOW NORMAL. && .AVIATION...SCT TO NUMEROUS TSRA/SHRA THRU THIS EVENING. WIND GUSTS AROUND 40-45 KTS AND MVFR CIGS/VSBYS WITH THE STRONGEST TSRA. PRECIP DECREASING IN COVERAGE LATE TONIGHT. SCT TSRA/SHRA TO OCCUR FRIDAY AFTERNOON. OTHERWISE...VFR CONDITIONS AND SURFACE WIND MOSTLY LESS THAN 10 KTS THRU FRIDAY AFTERNOON OR 08/00Z. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...SCATTERED THUNDERSTORMS WILL OCCUR INTO EARLY NEXT WEEK. EXPECT HEAVY RAINFALL WITH THE STRONGER THUNDERSTORMS. A GRADUAL DECREASE IN THUNDERSTORMS IS ON TAP BY THE MIDDLE OF NEXT WEEK. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/TUCSON
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TUCSON AZ 1017 AM MST THU SEP 6 2012 AZZ502>504-506>515-070600- TOHONO O'ODHAM NATION-UPPER SANTA CRUZ RIVER VALLEY/ALTAR VALLEY- TUCSON METRO AREA-SOUTHEAST PINAL COUNTY- UPPER SAN PEDRO RIVER VALLEY- EASTERN COCHISE COUNTY BELOW 5000 FEET-UPPER GILA RIVER VALLEY- WHITE MOUNTAINS OF GRAHAM AND GREENLEE COUNTIES- GALIURO AND PINALENO MOUNTAINS-CHIRICAHUA MOUNTAINS- DRAGOON AND MULE AND HUACHUCA AND SANTA RITA MOUNTAINS- CATALINA AND RINCON MOUNTAINS-BABOQUIVARI MOUNTAINS- 1017 AM MST THU SEP 6 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST ARIZONA. .DAY ONE...TODAY AND TONIGHT EXPECT SCATTERED TO NUMEROUS THUNDERSTORMS THROUGH THIS EVENING FOLLOWED BY A SLIGHT CHANCE OF THUNDERSTORMS LATE TONIGHT. THUNDERSTORM ACTIVITY EXPECTED TO BE ENHANCED AS AN UPPER DISTURBANCE APPROACHES FROM THE SOUTHEAST. THE MAIN THREAT WILL BE LOCALLY HEAVY RAINFALL AND BRIEF STRONG WIND GUSTS APPROACHING 50 MPH. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY THERE IS A CHANCE OF THUNDERSTORMS MAINLY DURING THE AFTERNOON AND EVENING HOURS INTO EARLY NEXT WEEK. THE MAIN THREAT WILL BE LOCALLY HEAVY RAINFALL DUE TO ABUNDANT MOISTURE ACROSS THE AREA. THEREAFTER...A GRADUAL DECREASE IN THUNDERSTORM CHANCES WILL OCCUR BY THE MIDDLE OF NEXT WEEK AS DEEPER MOISTURE MOVES EAST OF THE AREA. HOWEVER...THERE WILL STILL BE ENOUGH MOISTURE TO SUPPORT AT LEAST A SLIGHT CHANCE OF MAINLY AFTERNOON AND EVENING THUNDERSTORMS TUESDAY AND WEDNESDAY. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. AZZ505-070600- SOUTH CENTRAL PINAL COUNTY- 1017 AM MST THU SEP 6 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST ARIZONA. .DAY ONE...TODAY AND TONIGHT EXPECT SCATTERED THUNDERSTORMS THROUGH THIS EVENING FOLLOWED BY A SLIGHT CHANCE OF THUNDERSTORMS LATE TONIGHT. THUNDERSTORM ACTIVITY IS EXPECTED TO BE ENHANCED AS AN UPPER DISTURBANCE APPROACHES FROM THE SOUTHEAST. THE MAIN THREAT WILL BE LOCALLY HEAVY RAINFALL AND BRIEF STRONG WIND GUSTS APPROACHING 50 MPH. ALSO...STRONG THUNDERSTORM OUTFLOW MAY BE GENERATED LEADING TO AREAS BLOWING DUST AND REDUCED VISIBILITIES LATE THIS AFTERNOON AND EARLY THIS EVENING. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY THERE IS A CHANCE OF THUNDERSTORMS MAINLY DURING THE AFTERNOON AND EVENING HOURS INTO EARLY NEXT WEEK. THE MAIN THREAT WILL BE LOCALLY HEAVY RAINFALL DUE TO ABUNDANT MOISTURE ACROSS THE AREA. THEREAFTER...A GRADUAL DECREASE IN THUNDERSTORM CHANCES WILL OCCUR BY THE MIDDLE OF NEXT WEEK AS DEEPER MOISTURE MOVES EAST OF THE AREA. HOWEVER...THERE WILL STILL BE ENOUGH MOISTURE TO SUPPORT AT LEAST A SLIGHT CHANCE OF MAINLY AFTERNOON AND EVENING THUNDERSTORMS TUESDAY AND WEDNESDAY. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. AZZ501-070600- WESTERN PIMA COUNTY- 1017 AM MST THU SEP 6 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST ARIZONA. .DAY ONE...TODAY AND TONIGHT THERE IS A CHANCE OF THUNDERSTORMS THROUGH TONIGHT. THE MAIN THREAT WILL BE LOCALLY HEAVY RAINFALL ASSOCIATED WITH THE STRONGEST THUNDERSTORMS RESULTING IN FLASH FLOODING. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY A CHANCE OF THUNDERSTORMS WILL CONTINUE FRIDAY...PARTICULARLY DURING THE AFTERNOON AND EVENING HOURS. THE MAIN THREAT WILL BE LOCALLY HEAVY RAINFALL DUE TO AMPLE MOISTURE ACROSS THE AREA. THEREAFTER...A GRADUAL DECREASE IN THUNDERSTORM CHANCES WILL OCCUR SATURDAY THROUGH WEDNESDAY. HOWEVER...THERE WILL STILL BE ENOUGH MOISTURE FOR A SLIGHT CHANCE OF MAINLY AFTERNOON AND EVENING THUNDERSTORMS. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. WEATHER.GOV/TUCSON
The Tucson radar (KEMX), 17 km away, was scanning. The volume nearest the first event began at 21:38 UTC.
5 flash flood, 2 thunderstorm wind, 1 heavy rain, 1 flood. Local standard time, as filed.
Flash flooding caused the Sahuarita Road to become impassable near Ocotillo View.
Very heavy rain caused extensive street flooding in Ajo. Cedar Road was washed out by rapidly flowing flood waters 2 to 3 feet deep. a community health center and a school were also flooded. Farther south, Ajo Mountain Drive in Organ Pipe National Monument was closed as well as part of nearby Highway 85.
Very heavy rain collapsed ceiling tiles in an Ajo business, damaging some of the goods inside.
Thunderstorms produced 2 to 3 inches of rain in about 90 minutes causing many roads to be inundated by rapidly flowing flood waters on the southwest side of Tucson. AT least ten vehicles were caught up in the flood waters. Two people were rescued from vehicles at Sandario Road and Kinney Road while three more were rescued from a tree after their vehicle was washed away. Another five motorists in five separate vehicles were stranded near Ajo Way and Kinney Rpad. Bopp Road northwest of Ajo Way was washed out which caused Banks Elementary School students to become stranded in school until a detour around the washed out road could be fashioned. In addition, Gates Pass Road at Via Roma was flooded in the Tucson Mountains. No injuries occurred to any of the motorists.
Thunderstorm winds downed a tree near Ajo and Camino Verde Road.
A vehicle became stranded in flood waters on Arivaca Road.
Thunderstorm winds blew down an open ended Quonset hut outbuilding and a trailer in Hunter Estates near Duncan. Another trailer sustained considerable roof damage.
Up to three inches of rain fell in Duncan, causing flash flooding of most streets in Duncan's Hunter Estates where one home was also flooded. A wash that parallels and but remains just northwest of Carlisle Road climbed to a depth of about 8 feet, flooded Fairgrounds Road. Trees and other debris in the flood waters caused minor surface damage to the bridge at Fairgrounds Road before the waters entered the Gila River.
Heavy rain of two to four inches occurred the previous afternoon on Tucson's west side near Ajo Way and Kinney Road and directly over the Brawley Wash just west of Sandario Road. In addition, two to three inches of rain fell in the Sierrita Mountains west of Green Valley. By the time the runoff from the Sierrita Mountains reached the west side of Tucson many hours later, Brawley Wash overflowed its banks. During the overnight hours, five vehicles drove into the flood waters and became stranded along Manville Road just west of Sandario Road. Around 2 am, one man escaped his vehicle before it was washed downstream only to be swept several yards away himself. He suffered a leg injury. His vehicle was found 200 yards downstream, upside down. The man's wife was found in the vehicle, drown. Rain redeveloped around daybreak allowing flood conditions to persist through mid morning.
As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.
| Event | Date | Age | Sex | Where | Kind |
|---|---|---|---|---|---|
| Flood, Pima | 2012-09-07 | 52 | Female | Vehicle/Towed Trailer | Direct |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2012Every state in 2012This day in weather historyWarnings in Arizona, September 2012
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: 413887, 413885, 413886, 413890, 413888, 413889, 414294, 414298, 414369.