A continued southeast flow of moisture coupled with a mid level trough resulted in thunderstorms over Pima and Pinal Counties. Several storms produced damaging wind gusts.
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 continued southeast flow of moisture coupled with a mid level trough resulted in thunderstorms over Pima and Pinal Counties. Several storms produced damaging wind gusts.
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 11, 9:30 AM MST, 4 hours earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 930 AM MST SAT AUG 11 2012 .SYNOPSIS...HOT DAYTIME TEMPERATURES WILL CONTINUE INTO THE MIDDLE OF THE UPCOMING WEEK. NEAR RECORD HIGHS WILL OCCUR IN SOME LOCATIONS THIS WEEKEND. EXPECT SCATTERED THUNDERSTORMS WEST OF TUCSON THROUGH THIS EVENING. THUNDERSTORMS WILL BE LIMITED TO NEAR THE NEW MEXICO BORDER SUNDAY. SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS WILL THEN RETURN MONDAY THROUGH FRIDAY AS DEEPER MOISTURE RETURNS TO THE AREA. && .DISCUSSION...KEMX WSR-88D DETECTED ISOLATED 30-50 DBZ ECHOES MOVING NWWD ACROSS CENTRAL PIMA COUNTY AND SOUTH CENTRAL PINAL COUNTY AT 1605Z. THE REST OF SE AZ WAS VOID OF PRECIP ECHOES AT THIS TIME. SATELLITE IMAGERY AND SURFACE OBSERVATIONS INDICATED PARTLY CLOUDY SKIES FROM TUCSON WWD. MOSTLY CLEAR SKIES WERE ACROSS GREENLEE/ GRAHAM/COCHISE COUNTIES. DEWPOINTS VALID 16Z RANGED FROM THE LOWER 40S F NEAR THE WHITE MOUNTAINS TO THE NEAR 60 F VICINITY NOGALES AZ. THESE TEMPS WERE NEARLY IDENTICAL TO 24 HOURS AGO. SURFACE TEMPS VALID 16Z WERE ABOUT 2-5 DEGS F WARMER VERSUS THIS TIME FRI. BLENDED TOTAL PRECIP WATER IMAGERY DEPICTED VALUES RANGING FROM NEAR 1.00 INCH VICINITY WHITE MOUNTAINS TO AROUND 1.50 INCHES ACROSS WRN PIMA COUNTY. 11/12Z UPPER AIR PLOTS INDICATED 594 DM HIGH PRESSURE CENTERED OVER NWRN NEW MEXICO WITH RIDGE AXIS EXTENDING NWWD INTO THE PACIFIC NW. DIFFLUENT FLOW AT 300 MB WAS ACROSS SE AZ...AND MID-LEVEL STEERING FLOW WAS SELY AROUND 10 KTS. INVERTED TROF MOVING NWWD ACROSS FAR NWRN SONORA WILL MOVE NW ACROSS SWRN AZ INTO THIS EVENING. NW-SE AXIS OF DEEPER MOISTURE AS WELL AS DIFFLUENT UPPER FLOW JUSTIFIES SCATTERED SHOWERS/TSTMS ACROSS WRN/ CENTRAL PIMA COUNTY SEWD INTO SANTA CRUZ COUNTY INTO THIS EVENING. FOR NOW WILL MAINTAIN ISOLATED SHOWERS/TSTMS FOR THE TUCSON METRO AREA THRU THIS EVENING. HOWEVER...11/12Z NAM ARGUES FOR DRY CONDITIONS FOR TUCSON. PRECIP-FREE CONDITIONS JUSTIFIED ACROSS GRAHAM AND COCHISE COUNTIES...AND A SLIGHT CHANCE OF SHOWERS/TSTMS VICINITY WHITE MOUNTAINS. DRY CONDITIONS AREA WIDE LATE TONIGHT AS THE INVERTED TROUGH ADVANCES WELL NW OF THIS FORECAST AREA. SUN... SHOWERS/TSTMS FORECAST TO BE LIMITED TO THE HIGHER TERRAIN EAST OF TUCSON AND ESPECIALLY TO NEAR THE NEW MEXICO BORDER AS PER THE 11/12Z NAM. MON... DEEPER MOISTURE IS PROGGED TO ADVECT WWD ACROSS SE AZ. THE INHERITED OFFICIAL FORECAST DEPICTS SCATTERED AFTERNOON AND EVENING SHOWERS/ TSTMS FROM TUCSON EWD/SWD WITH LESSER PRECIP CHANCES ACROSS WRN SECTIONS. MAIN CONCERN FOR MON WILL BE THE THREAT FOR DAMAGING WIND GUSTS DUE TO A QUITE DRY NEAR-SURFACE ENVIRONMENT. TUE-FRI... DAILY PRECIP CHANCES TO GRADUALLY INCREASE THIS PERIOD AS UPPER RIDGE REMAINS JUST EAST OF THE AREA. IN SUMMARY...SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS/TSTMS MAINLY FROM TUCSON EWD/SWD WITH LESSER SHOWER/TSTM ACTIVITY ACROSS WRN SECTIONS. THE HOTTEST TEMPERATURES OF THE YEAR ARE FORECAST SUNDAY AND MONDAY WITH THE LOW DESERTS NEAR HEAT ADVISORY CRITERIA. COOLING TREND TO OCCUR DURING THE LATTER PART OF THE UPCOMING WEEK. && .AVIATION...ISOLD-SCT -TSRA/-SHRA MAINLY SOUTH AND WEST OF KTUS THRU THIS EVENING THEN DRY CONDITIONS AREA WIDE 06Z-12Z SUNDAY. BRIEF WIND GUSTS APPROACHING 40 KTS WITH THE STRONGEST TSRA. OTHERWISE...VFR CONDITIONS AND SURFACE WIND GENERALLY LESS THAN 10 KTS THRU LATE TONIGHT OR 12/12Z. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...SCATTERED THUNDERSTORMS WILL OCCUR MAINLY WEST OF TUCSON INTO THIS EVENING. ISOLATED TO SCATTERED THUNDERSTORMS WILL THEN OCCUR MAINLY NEAR THE HIGHER TERRAIN SUNDAY. THUNDERSTORM CHANCES WILL GRADUALLY INCREASE DURING THE UPCOMING WEEK AS DEEPER MOISTURE RETURNS TO THE AREA. OTHERWISE...EXPECT HOT DAYTIME TEMPERATURES WITH NORMAL DIURNAL WIND TRENDS INTO THE MIDDLE OF THE UPCOMING WEEK. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. WEATHER.GOV/TUCSON
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TUCSON AZ 946 AM MST SAT AUG 11 2012 AZZ501>503-505-515-120600- WESTERN PIMA COUNTY-TOHONO O'ODHAM NATION- UPPER SANTA CRUZ RIVER VALLEY/ALTAR VALLEY- SOUTH CENTRAL PINAL COUNTY-BABOQUIVARI MOUNTAINS- 946 AM MST SAT AUG 11 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST ARIZONA. .DAY ONE...TODAY AND TONIGHT SCATTERED THUNDERSTORMS WILL OCCUR THROUGH THIS EVENING FOLLOWED BY DRY CONDITIONS LATE TONIGHT. THE STRONGEST THUNDERSTORMS WILL BE CAPABLE OF PRODUCING DAMAGING WIND GUSTS...PARTICULARLY THIS AFTERNOON AND EARLY THIS EVENING. OTHERWISE...HOT TEMPERATURES WILL OCCUR AGAIN TODAY. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY DRY CONDITIONS ARE EXPECTED SUNDAY. THEREAFTER...THUNDERSTORM CHANCES WILL GRADUALLY INCREASE MONDAY THROUGH FRIDAY AS DEEPER MOISTURE RETURNS TO THE AREA. HOT DAYTIME TEMPERATURES WILL CONTINUE SUNDAY THROUGH TUESDAY FOLLOWED BY A COOLING TREND BY THE END OF THE WEEK. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. AZZ504-506-514-120600- TUCSON METRO AREA-SOUTHEAST PINAL COUNTY- CATALINA AND RINCON MOUNTAINS- 946 AM MST SAT AUG 11 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST ARIZONA. .DAY ONE...TODAY AND TONIGHT THERE IS A SLIGHT CHANCE OF THUNDERSTORMS THROUGH THIS EVENING FOLLOWED BY DRY CONDITIONS LATE TONIGHT. OTHERWISE...HOT TEMPERATURES WILL OCCUR AGAIN TODAY. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY DRY CONDITIONS ARE EXPECTED SUNDAY. THEREAFTER...THUNDERSTORM CHANCES WILL GRADUALLY INCREASE MONDAY THROUGH FRIDAY AS DEEPER MOISTURE RETURNS TO THE AREA. HOT DAYTIME TEMPERATURES WILL CONTINUE SUNDAY THROUGH TUESDAY FOLLOWED BY A COOLING TREND BY THE END OF THE WEEK. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. AZZ510-120600- WHITE MOUNTAINS OF GRAHAM AND GREENLEE COUNTIES- 946 AM MST SAT AUG 11 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST ARIZONA. .DAY ONE...TODAY AND TONIGHT THERE IS A SLIGHT CHANCE OF THUNDERSTORMS THIS AFTERNOON AND THIS EVENING. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS WILL OCCUR SUNDAY THROUGH FRIDAY. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. AZZ507>509-511>513-120600- UPPER SAN PEDRO RIVER VALLEY- EASTERN COCHISE COUNTY BELOW 5000 FEET-UPPER GILA RIVER VALLEY- GALIURO AND PINALENO MOUNTAINS-CHIRICAHUA MOUNTAINS- DRAGOON AND MULE AND HUACHUCA AND SANTA RITA MOUNTAINS- 946 AM MST SAT AUG 11 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST ARIZONA. .DAY ONE...TODAY AND TONIGHT DRY CONDITIONS WILL PREVAIL THROUGH TONIGHT. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY THERE IS A SLIGHT CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS MAINLY NEAR THE MOUNTAINS SUNDAY. THEREAFTER...THUNDERSTORM CHANCES WILL GRADUALLY INCREASE MONDAY THROUGH FRIDAY AS DEEPER MOISTURE RETURNS TO THE AREA. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. WEATHER.GOV/TUCSON
The Tucson radar (KEMX), 44 km away, was scanning. The volume nearest the first event began at 20:29 UTC.
4 thunderstorm wind. Local standard time, as filed.
Thunderstorm winds downed a tree at Mission Manor Park in Tucson and flipped over a loosely anchored small metal shed at San Joaquin Road and West Milky Way Drive.
Thunderstorm winds downed a tree at Catalina Regional Park. The tree fell on a park shelter, damaging the roof.
Thunderstorm winds damaged three homes and a cellular tower near Menager's Dam.
Thunderstorm winds damaged two homes in Hickiwan. One home sustained considerable roof damage.
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, August 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: 408860, 408918, 408945, 408928.