Storm near Phoenix
Wednesday, August 18, 2021
- Largest hail
- 0.75 inpenny
- Strongest wind
- 64 mphgust
- Tornadoes
- 0none reported
- Reports
- 7within 15 mi
7 reports
- 0.75 in hail (penny)13.0 mi NNE of central Phoenix3.5 mi W of Scottsdale Muni · Maricopa County · Trained Spotter
- 60 mph gust (estimated)5.2 mi NNW of central Phoenix3.3 mi NNW of Phoenix · Maricopa County · Broadcast Media
Multiple large trees uprooted in the area of 19th Ave between Missouri Ave and Maryland with some trees falling into and blocking streets. One tree was 30 feet tall and had a 12-18 inch diameter trunk. A large tree also reportedly fell at Palo Verde golf course. Timing was based on radar and wind gusts were estimated up to 50-60 mph with downburst signatures evident on radar. No injuries were reported.
- 60 mph gust (estimated)8.5 mi N of central Phoenix0.6 mi SSW of Sunnyslope · Maricopa County · Broadcast Media
A portion of the roof of an apartment complex near 7th Avenue and Hatcher Road was torn of in strong winds and landed on an unoccupied parked car, causing damage. Nearby, multiple photos on social media showed several downed saguaros with one of them causing some damage to the front of a home near 12th Street and Northern Avenue. Winds estimated around 60 to 65 mph. No injuries were reported.
- 64 mph gust (estimated)10.3 mi NNW of central Phoenix3.9 mi NNE of Glendale · Maricopa County · Trained Spotter
Multiple reports of wind damage from a microburst along Peoria Avenue between 35th and 43rd Avenues. A couple large pine trees fell on an apartment complex, causing damage to the edge of the roof. A tree fell on 2 unoccupied parked cars at another apartment complex, causing major damage. A 1-foot diameter tree fell on an unoccupied parked car at a business plaza. There was also a partial roof torn off reported in the area. Winds were estimated around 60 to 65 mph. Timing based on radar. No injuries were reported.
- 60 mph gust (estimated)13.2 mi E of central Phoenix1.6 mi W of Mesa · Maricopa County · Utility Company
A large tree, possibly a palm tree, was blown down onto power lines along Extension Road between 2nd Street and 2nd Place, causing a power outage to approximately 600 customers. Winds estimated around 55 to 65 mph. Timing based on radar. No injuries were reported.
- 58 mph gust (estimated)13.1 mi W of central Phoenix0.7 mi N of Cashion · Maricopa County · Public
Pictures on social media show multiple snapped tree due to strong downburst winds. Wind speeds estimated around 55 to 60 mph. Timing based on radar. No injuries were reported.
- 58 mph gust (estimated)9.9 mi S of central Phoenix6.1 mi W of West Chandler · Maricopa County · Trained Spotter
Numerous trees down across Ahwatukee with many along Desert Foothills Parkway and Chandler Boulevard over to Ray Road. Many of the trees were palo verdes and several fell into roads and impeded traffic. Winds estimated around 50 to 60 mph. Time based on radar. No injuries were reported.
Also hit that day: Glendale, AZ, Peoria, AZ
What the National Weather Service wrote
An upper level trough and lead-on shortwave trough moved through Arizona during the day on the 18th. Moderate to high instability and high moisture content supported scattered strong thunderstorms. With deep south to southwest upslope flow, storms favored the foothills and mountainous areas of Maricopa and Gila counties. Most storms were producing at least 1 to 2 inch per hour rain rates, with several storms producing 2 to 3 inch rates and at times higher. Back-building and training of storms over the same areas resulted in significant to catastrophic flash flooding. A few burn scars experienced flash flooding, including the recent Telegraph burn area which had catastrophic flooding of the Russell Gulch drainage. There were also 2 fatalities on this day with off-roaders recreating near Camp Creek in northeast Maricopa County. The strong to severe storms also produced damaging winds from microbursts and small hail over lower desert locations.