Isolated thunderstorms moved west across Pima County during the late afternoon and evening hours. A few storms produced damaging winds and flash flooding.
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.
Isolated thunderstorms moved west across Pima County during the late afternoon and evening hours. A few storms produced damaging winds and flash flooding.
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 30, 1:55 PM MST, 4 hours 5 minutes earlier.
Area Forecast Discussion National Weather Service Tucson AZ 155 PM MST Fri Jul 30 2021 .SYNOPSIS...Isolated to scattered showers and thunderstorms can be anticipated this evening and Saturday. Thereafter, the overall trend in thunderstorm coverage will be less for most of next week and focused south and east of Tucson. High temperatures will trend up next week with readings peaking around Tuesday. && .DISCUSSION...Regional radar imagery was showing a few showers and thunderstorms already developing, mainly in the mountains, early this afternoon. The general area of concern for flash flooding will be west of Tucson where a Flash Flood Watch remains in effect through late tonight for western and central Pima county. The greater Tucson metro will be on the fringes, so cannot rule out an isolated thunderstorm with heavy downpours impacting the city. Ensembles favored a decreasing trend in daily thunderstorm coverage Sunday into the work week with no strong signal indicating otherwise. High temperatures will also peak slightly above normal around Tuesday based on limited thunderstorm activity and a relatively drier airmass in place. && .AVIATION...Valid through 01/00Z. Increasing clouds into this evening becoming SCT-BKN 10k-14k ft MSL. ISOLD-SCT SHRA/TSRA through early Saturday morning with strong erratic wind gusts in excess of 30 kts, heavy downpours, and temporary MVFR CIGS/VSBYS. ISOLD-SCT SHRA/TSRA redeveloping Saturday afternoon. Outside of TSRA outflows, SFC wind will generally remain less than 12 kts. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Scattered showers and thunderstorms area-wide today before a downward trend in storm activity this weekend into early next week when storm chances will mainly be from Tucson eastward. Storms will likely produce erratic, gusty winds and locally heavy downpours. RH values remain well above critical thresholds through at least the middle of next week. Temps will remain near to slightly below normal. 20-foot winds will generally be less than 15 mph when not influenced by thunderstorms. && .TWC WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch through late tonight for public zones AZZ501-502. && Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Special Weather Statement National Weather Service Tucson AZ 238 PM MST Fri Jul 30 2021 AZZ503-302230- Upper Santa Cruz River and Altar Valleys including Nogales- 238 PM MST Fri Jul 30 2021 ...SIGNIFICANT WEATHER ADVISORY FOR SOUTH CENTRAL PIMA AND WESTERN SANTA CRUZ COUNTIES UNTIL 330 PM MST... At 238 PM MST, Doppler radar was tracking a strong thunderstorm near Rio Rico, or 7 miles southeast of Tubac, moving west at 5 to 10 mph. Half inch hail and wind gusts up to 50 mph will be possible with this storm. Locations impacted include... Tubac, Rio Rico and Tumacacori. PRECAUTIONARY/PREPAREDNESS ACTIONS... Heavy rainfall is also occurring with this storm, and may lead to localized flooding. Do not drive your vehicle through flooded roadways. This storm may intensify, so be certain to monitor local radio stations and available television stations for additional information and possible warnings from the National Weather Service. && LAT...LON 3160 11092 3142 11094 3141 11121 3169 11119 TIME...MOT...LOC 2138Z 103DEG 6KT 3152 11100 Meyer
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TUCSON AZ
408 PM MST FRI JUL 30 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0745 PM FLASH FLOOD 8 NNE RIO RICO 31.60N 110.93W
07/29/2021 SANTA CRUZ AZ NEWSPAPER
*** 1 FATAL, 1 INJ ***
TEENAGERS RECREATING IN WATER NEAR A
WATERFALL WERE SWEPT DOWNSTREAM BY A RAPID
RISE IN THE WATER LEVEL. ONE TEENAGER
DROWNED. ANOTHER ESCAPED THE FLOOD WATERS
WHILE SUSTAINING MINOR INJURIES AND WAS
LATER RESCUED.
&&
KDThe Phoenix radar (KIWA), 152 km away, was scanning. The volume nearest the first event began at 01:02 UTC.
3 flash flood, 2 thunderstorm wind. Local standard time, as filed.
One to two inches of rain in less than 1 hour from south of Ajo to east of Why. This caused flash flooding of area washes and the closure of Highway 86 east of Why and Highway 85 between Ajo and Why.
Thunderstorm winds downed a power pole near Nolic.
A wind gust to 67 mph was recorded at Tucson International Airport.
One to two inches of rain fell in less than 1 hour northeast of the Tucson International Airport causing flash flooding of area roads. One swift water rescue was conducted for a vehicle stalled in a wash.
More than 1 of rain fell in less than 1 hour along South Wilmot Rd causing flash flooding and the closure of the roadway north of Sahuarita Rd.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2021Every state in 2021This day in weather historyWarnings in Arizona, July 2021
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: 976561, 976548, 976549, 976553, 976558.