A favorable position of the Monsoon high pressure system and increasing moisture resulted in a second consecutive day of strong to severe thunderstorms across much of southern Arizona.
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 favorable position of the Monsoon high pressure system and increasing moisture resulted in a second consecutive day of strong to severe thunderstorms across much of southern Arizona.
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 Jul 5, 9:07 AM MST, 4 hours 3 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 907 AM MST TUE JUL 5 2011 .SYNOPSIS...DEEP MOISTURE AND A FAVORABLE FLOW WILL PROVIDE AFTERNOON AND EVENING THUNDERSTORMS THIS WEEK. SOME STORMS WILL GENERATE STRONG WINDS AND HEAVY RAIN. && .DISCUSSION...LOTS OF SUNSHINE CURRENTLY OVER SE AZ WILL PROVIDE HEATING TO HELP LIFT MOIST AIR IN PLACE OVER THE AREA. PRECIPITABLE WATER...A.K.A. PW...VALUES OVER 1.5 INCHES ON 12Z SOUNDING AND EVIDENT ON SATELLITE BLENDED TOTAL PW IMAGERY. THIS IMAGERY ALONG WITH WATER VAPOR CHANNEL SHOW BEST MOISTURE FROM TUCSON S AND W WITH EASTERN AREAS A LITTLE DRIER. 300 MB STREAMLINES AND 12Z NAM INDICATES FAVORABLE UPPER DIFFLUENCE/DIVERGENCE OVER AREA TODAY...WHICH WILL ENHANCE VENTING OF STORMS THAT DEVELOP TODAY. BOTTOM LINE FOR TODAY...GOING FORECAST HIGHLIGHTING MOST FAVORED AREAS FROM TUCSON SOUTH AND WESTWARD IS SUPPORTED BY LATEST U OF A NAM WRF. IN ADDITION...STORM PREDICTION CENTER ASSESSMENT OF DOWNBURST POTENTIAL GIVEN MID LEVEL WIND FIELDS ALSO APPEARS ON TRACK. THEREFORE ONLY ADJUSTMENT TO CURRENT FORECAST FOR NEXT 18 HOURS MAY BE TO RAISE RAIN CHANCES INTO LIKELY CATEGORY AS INDICATED BY LATEST NAM NUMERICAL GUIDANCE...KD && .AVIATION...SCT TSRA/SHRA DEVELOPING AROUND 18Z TODAY AND CONTINUING THRU 06Z WEDNESDAY. MVFR CIGS AND MT OBSCURATIONS NEAR THUNDERSTORMS. WIND GUSTS OF 40-45 KTS VICINITY STRONGER TSRA. OTHERWISE SURFACE WIND GENERALLY LESS THAN 10 KTS. PRECIP TO DECREASE IN COVERAGE 06Z-12Z WEDNESDAY. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...EXPECT SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS INTO EARLY NEXT WEEK. STRONG...ERRATIC AND GUSTY WINDS WILL OCCUR WITH THE THUNDERSTORM OUTFLOWS ALONG WITH LOCALIZED HEAVY RAIN. OTHERWISE...A NORMAL DIURNAL WIND REGIME AND NEAR NORMAL DAYTIME TEMPERATURES WILL OCCUR INTO EARLY NEXT WEEK. && .PREV DISCUSSION...OTHERWISE...HIGH PRESSURE ALOFT CENTERED OVER NRN NEW MEXICO EARLY THIS MORNING TO REMAIN QUASI-STATIONARY THRU FRI. MOISTURE TO REMAIN SUFFICIENT FOR SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS/TSTMS WED-FRI. UPPER HIGH IS THEN PROGGED VIA THE 05/00Z GFS/ECMWF TO BECOME CENTERED OVER THE MIDDLE MISSISSIPPI RIVER VALLEY REGION BY NEXT MON. MEANWHILE...TROUGH IS EXPECTED TO ENCROACH UPON THE WEST COAST. ALTHOUGH SOME PORTIONS OF THE STATE MAY SEE A DOWNTURN IN MOISTURE...NO APPRECIABLE MOISTURE CHANGE IS EXPECTED ACROSS SE AZ. THUS...THE DAILY CYCLE OF MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS SHOULD CONTINUE THIS WEEKEND AND EARLY NEXT WEEK. NEAR NORMAL DAYTIME TEMPS TO OCCUR TODAY-MON...BF .TWC WATCHES/WARNINGS/ADVISORIES...NONE. WEATHER.GOV/TUCSON
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TUCSON AZ 1147 AM MST TUE JUL 5 2011 AZZ501>515-060600- WESTERN PIMA COUNTY-TOHONO O'ODHAM NATION- UPPER SANTA CRUZ RIVER VALLEY/ALTAR VALLEY-TUCSON METRO AREA- SOUTH CENTRAL PINAL COUNTY-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- 1147 AM MST TUE JUL 5 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST ARIZONA. .DAY ONE...THIS AFTERNOON AND TONIGHT THUNDERSTORMS ARE EXPECTED TO BE THE MOST WIDESPREAD FROM TUCSON WESTWARD THIS AFTERNOON AND EVENING...BUT AT LEAST ISOLATED THUNDERSTORMS ARE POSSIBLE ANYWHERE IN SOUTHEAST ARIZONA. THE STRONGEST THUNDERSTORMS WILL ONCE AGAIN BE CAPABLE OF PRODUCING DAMAGING WINDS. GUSTY WINDS COULD RESULT IN REDUCED VISIBILITIES IN BLOWING DUST. SOME STORMS COULD ALSO PRODUCE NEARLY AN INCH OF RAIN IN LESS THAN 30 MINUTES...WHICH COULD RESULT IN FLASH FLOODING. LIGHTER RAIN AMOUNTS COULD PRODUCE FLASH FLOODING OVER AND NEAR WILDFIRE BURN SCAR AREAS. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED EVERY DAY INTO EARLY NEXT WEEK MAINLY FROM EARLY AFTERNOON INTO THE EVENING. THUNDERSTORMS WILL PRODUCE DANGEROUS LIGHTNING STRIKES AND MAY CONTAIN POTENTIALLY DAMAGING WIND GUSTS AND FLASH FLOOD PRODUCING HEAVY RAIN. EVEN MODERATE PRECIPITATION OVER THE AREAS SEVERELY BURNED BY WILDFIRES WILL RESULT IN FLASH FLOODING. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. KD WEATHER.GOV/TUCSON
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TUCSON AZ
1234 PM MST TUE JUL 5 2011
AZZ503-513-052015-
DRAGOON/MULE/HUACHUCA AND SANTA RITA MOUNTAINS INCLUDING
BISBEE/CANELO HILLS/MADERA CANYON AZ-UPPER SANTA CRUZ RIVER AND ALTAR
VALLEYS INCLUDING NOGALES AZ-
1234 PM MST TUE JUL 5 2011
...SIGNIFICANT WEATHER ADVISORY FOR WESTERN SANTA CRUZ COUNTY UNTIL
115 PM MST...
AT 1231 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING
A STRONG THUNDERSTORM 9 MILES EAST OF NOGALES...MOVING WEST AT 30
MPH.
WIND GUSTS UP TO 50 MPH ARE EXPECTED WITH THIS STORM...ALONG WITH
FREQUENT DANGEROUS LIGHTNING.
AREAS AFFECTED BY THIS STORM INCLUDE...NOGALES...TUBAC...PATAGONIA
LAKE...RIO RICO...PENA BLANCA LAKE AND TUMACACORI.
IF THREATENING WEATHER APPROACHES YOUR AREA...TAKE SHELTER IN A
STURDY BUILDING.
IN ADDITION...THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR
LOCAL RADIO AND TV STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR
ADDITIONAL INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL
WEATHER SERVICE.
LAT...LON 3139 11127 3152 11116 3167 11105 3141 11066
3133 11071 3133 11106
TIME...MOT...LOC 1934Z 112DEG 24KT 3136 11081
KDThe Tucson radar (KEMX), 51 km away, was scanning. The volume nearest the first event began at 20:11 UTC.
5 thunderstorm wind, 1 hail, 1 flash flood. Local standard time, as filed.
Trained spotter reported one inch diameter hail covering the ground with hail depths up to 2 inches in spots.
Tohono O'odham Emergency Manager reported structural damage to two homes in Sells with estimated winds near 50 knots (58 mph). The homes both suffered partial roof collapses.
Strong thunderstorm winds resulted in significant damage around southern portions of the Tucson Metro area. Davis-Monthan Air Force Base recorded a wind gust of 67 knots (77mph) while the Tucson International Airport recorded a gust of 61 knots (70 mph). The most significant damage was sustained by businesses in South Tucson. Near Ajo Way and County Club, two industrial buildings sustained partial roof collapses with one business losing the entire roof. A Safeway Grocery Store in the Rita Ranch Village suffered a partial roof collapse. Several power poles and power lines were also downed with several blown transformers. Around 27,000 residents were without power at the peak of the storm. Several trees were downed, with trees falling on homes, cars, and into traffic creating road closures. The most significant tree damage was at the McGuire Hills Apartment Complex. Several trees were downed blocking access to many of the apartments.
Widespread rainfall amounts across the Tucson Metro area ranged from one half to three quarters of an inch with some spots receiving up to two inches. Several washes were running with some spilling over into local streets. This resulted in several streets being closed. There were also a stalled car on East Irvington at the Rodeo Wash near the Tucson International Airport. The driver was able to safely seek higher ground.
Tohono O'odham Nation Emergency Manager reported thunderstorm winds caused structural damage to two homes in Lukeville. One home suffered minor roof damage while the other home suffered a partial roof collapse. Another home was damaged in the Gu Vo District of the Tohono O'odham. The home had damage to the roof and walls.
A strong line of thunderstorms continued to track to the northwest across the Tucson area resulting in more significant wind damage. Several trees were downed along a line from River Road and Interstate 10 to the Gladden Farms neighborhood. In Gladden Farms, aside from trees downed, a twenty foot section of a brick wall was blown down. Additional damage was observed in Oro Valley with several trees down and outbuildings blown apart.
A trained spotter in Saddlebrooke reported significant thunderstorm wind damage. Several large, established trees were downed causing minor roof damage, and brick walls blown down. In Avra Valley, mesquite trees were snapped at the base while large limbs were broke off others.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2011Every state in 2011This day in weather historyWarnings in Arizona, July 2011
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: 328635, 328641, 328573, 328651, 328642, 328624, 328629.