Scattered thunderstorms developed and moved west across Pima and Pinal counties during the evening. Several power poles were downed on the Tohono O'odham Nation.
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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.
Scattered thunderstorms developed and moved west across Pima and Pinal counties during the evening. Several power poles were downed on the Tohono O'odham Nation.
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, 2:37 PM MST, 5 hours 23 minutes earlier.
Area Forecast Discussion National Weather Service Tucson AZ 237 PM MST Sun Jul 30 2023 .SYNOPSIS...Hot temperatures again today with scattered showers and thunderstorms. Some storms will generate strong winds and locally heavy rain. Monday expect an uptick in storm strength and coverage with flash flooding possible as well. Temperatures cool to near normal Monday through Wednesday. Rain chances dwindle after Tuesday as drier air moves in. Hotter temperatures return by next weekend. && .DISCUSSION...Early afternoon convection starting near the mountains and favored locations discussed this morning. The 12Z KTWC sounding suggests another day with strong convective potential. Precipitable water near average for late July, coming in at 1.37 inches. Sfc and MU CAPE near 1.9k, but a little less shear than recent days. Latest RAP keeping CAPE near or above those levels while bumping PW up a little from Tucson westward, even as Cochise county falls toward 3/4 of an inch. The HRRR continues to show eastern areas struggling with lower surface dewpoints spreading through Cochise County, currently dropping into the lower 40s. The most favorable area is still likely be the T.O. Nation into western Pima County, with an increasing moisture gradient and weak upper level diffluence ahead of the weakening inverted trough that's rotating up from the south. It looks like Tucson will be on the far eastern edge of the busiest storm environment. As expected, steering level flows and a sharpening east/west moisture gradient has seen the outflow propagating from the Mogollon Rim more oriented toward Pinal County in the evening hours. However, we're not ruling out another batch for the greater Tucson area. The weakening inverted trough rotating up the western flank of the high is now over southern Sonora and Chihuahua. This feature is expected to bring a few showers up from the south early tomorrow, and could push enough debris cloud into the area to limit insolation Monday. If that occurs, we may end up with our first daytime high temperature below 100 at Tucson Airport since mid June. The dynamics and shear associated with the afore mentioned impulse will likely enhance both coverage and intensity of storms Monday afternoon into the early evening hours. With precipitable water values pushing closer to 1.5 inches, we'll have to watch for wet microburst activity with both elevated chances for severe and localized flash flooding. That is, as long as we don't gunk over too much in the morning and struggle to reach a convective temperature. Some drying as early as Tuesday afternoon, with weak subsidence behind the impulse limiting thunderstorm coverage. Additional drying the second half of the week with well below average thunderstorm coverage expected as the ridge builds back in from the east and into a blocking position through southeast Arizona and northwest Mexico by the end of the week. Both GEFS and ECMWF thicknesses still support a return to 110+ next Saturday, with the NBM coming in with 109 and a 41% chance of 110 Friday through Sunday. It's not east to hit 110 in August, with only 11 total 110 days all time recorded in Tucson (4 of them in 2020). Both GEFS and ECMWF 5 day ensemble means still suggest positive height anomalies over our area through mid August. Something that even the elevated tropical activity expected off the western Mexico coast over the next 7 days will have a hard time impacting (a named storm is expected to form and track south of the Baja Peninsula this week). It looks like the main story will once again shift back to record breaking heat. && AVIATION...valid through 01/00Z. Isolated to scattered SHRA/TSRA, potentially impacting KTUS and KOLS through 31/05Z. Increased storm coverage and intensity Monday. Gusty outflow winds to 40+ kts along with VSBY reductions to 3SM or less are possible with TSRA. Outside of thunderstorm outflows, afternoon SFC winds will be SELY around 15 kts becoming light and terrain driven overnight. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Isolated to scattered afternoon and evening showers and thunderstorms are expected across portions of southeast Arizona this afternoon with a substantial increase in coverage and rainfall potential tomorrow afternoon. Storms will be capable of producing strong, gusty, and erratic outflow winds of 45 mph or higher. Although sustained 20-foot winds will generally remain under 15 mph today, gusts to around 25 mph may occur. Temperatures will remain hot but will be a few degrees cooler today with continued cooling expected through the middle of the week before warming up again Wednesday and beyond. Valley min RH readings will generally range between 15-25% today before increasing to 20-30% for tomorrow and Tuesday. Conditions gradually dry out by the end of next week with valley min RH values of 15-25% Wednesday and 10-20% for Thursday and beyond. && .TWC WATCHES/WARNINGS/ADVISORIES... None. && Meyer Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
Preliminary Local Storm Report
National Weather Service Tucson AZ
211 PM MST Sun Jul 30 2023
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0820 PM Tstm Wnd Gst 6 ESE Tucson 32.17N 110.79W
07/29/2023 M76 MPH Pima AZ NWS Employee
Delayed report: Many homes in the area had
roof/awning/carport/shed damage with
numerous large limbs and smaller trees
downed.
&&
CCSpecial Weather Statement
National Weather Service Tucson AZ
412 PM MST Sun Jul 30 2023
AZZ502-310000-
Tohono O'odham Nation including Sells-
412 PM MST Sun Jul 30 2023
...A strong thunderstorm will impact portions of south central Pima
County through 500 PM MST...
At 412 PM MST, Doppler radar was tracking a strong thunderstorm over
Topawa, or 9 miles southeast of Sells, moving west at 10 mph.
HAZARD...Wind gusts up to 50 mph and penny size hail.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor damage to outdoor objects is
possible.
Locations impacted include...
Sells, Topawa, San Miguel, Vamori, Cowlic, Choulic, Coldfields,
Artesia, Hashan Chuchg, South Komelik, Itak and Ali Molina.
This includes Route 86 between mile markers 107 and 117.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
&&
LAT...LON 3166 11211 3199 11198 3185 11167 3155 11176
TIME...MOT...LOC 2312Z 109DEG 10KT 3180 11179
MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH
GELSpecial Weather Statement
National Weather Service Tucson AZ
718 PM MST Sun Jul 30 2023
AZZ502-504-505-310315-
Tohono O'odham Nation including Sells-Tucson Metro Area including
Tucson/Green Valley/Marana/Vail-South Central Pinal County including
Eloy/Picacho Peak State Park-
718 PM MST Sun Jul 30 2023
...A strong thunderstorm will impact portions of north central Pima
and southwestern Pinal Counties through 815 PM MST...
At 716 PM MST, Doppler radar was tracking a group of strong
thunderstorms from just west of Avra Valley northwest to North
Komelik, all moving northwest at 35 mph.
HAZARD...Winds in excess of 40 mph, half inch hail and local
blowing dust.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor damage to outdoor objects is
possible.
Locations impacted include...
Santa Rosa, Chui-Chu, Red Rock, Anegam, Cockleburr, North Komelik,
Kohatk, Palo Verde Stand, Ventana, Ak Chin, Queens Well, Sil Nakya,
Jack Rabbit, Shopishk, San Luis, Santa Rosa School, Silver Bell and
East Chui-Chu.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
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 3230 11219 3250 11232 3251 11221 3268 11220
3268 11216 3272 11215 3272 11205 3277 11205
3277 11188 3279 11187 3279 11178 3273 11174
3273 11167 3276 11160 3256 11133 3215 11159
TIME...MOT...LOC 0216Z 123DEG 31KT 3246 11182
MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH
CSCThe Phoenix radar (KIWA), 113 km away, was scanning. The volume nearest the first event began at 03:01 UTC.
2 thunderstorm wind. Local standard time, as filed.
Thunderstorm winds downed a power pole in the Santa Rosa area.
Thunderstorm winds downed 3 power poles in the San Simon, Kuakatch and Charco 27 areas.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2023Every state in 2023This day in weather historyWarnings in Arizona, July 2023
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: 1124331, 1124332.