Tucson, AZ Hail Storm – July 2025

What Happened

A severe thunderstorm crossed the Tucson, AZ metro on 2025-07-03, producing verified 1-inch hail and a run of flash flooding reports through the afternoon. The storm remained active from early afternoon into late afternoon, with three NWS alert areas issued at 1:53 PM MST, 2:43 PM MST, and 4:23 PM MST.

The first two alerts carried radar and spotter-verified confidence for 1-inch hail. The third alert at 4:23 PM MST kept the same hail size, with dual-polarization radar support from NEXRAD. In the field, reports began building soon after the first alert window. Around 2:25 PM MST, delayed reports noted thunderstorm wind damage to roofing, with radar used to estimate timing. A 2:30 PM MST report from the metro noted a palm tree knocked down and nickel-size hail.

Flooding reports followed quickly. At 2:45 PM MST, an NWS employee reported flash flooding along 1st Street from River Road to Grant Road, with water crossing roads at several junctions. By 2:55 PM MST, a spotter reported 1.3 inches of rain in 45 minutes and yard flooding. At 3:00 PM MST, South Old Nogales Highway was closed at Flato Wash because of flash flooding. A 3:16 PM MST report placed a swift water rescue ongoing at Prince and River Park Drive. By 4:10 PM MST, Old Nogales Highway south of Lumber was closed due to flooding.

Damage Assessment

The surface impact in Tucson centered on water. The field reports show road closures, street flooding, and at least one swift water rescue across the metro. 1st Street from River Road to Grant Road had multiple flooded junctions. South Old Nogales Highway was shut at Flato Wash. Old Nogales Highway south of Lumber also closed later in the event. These were not isolated nuisance puddles. They were repeated flood impacts across different parts of the metro during the same storm cycle.

Wind damage also appeared in the report set. A spotter described roofing damage tied to thunderstorm wind gusts in a delayed report at 2:25 PM MST. Another report at 2:30 PM MST noted a palm tree down in the storm area. The hail report from that same time frame included nickel-size stones, which fits the broader picture of a storm producing both hail and wind impact as it moved through Tucson.

The rain totals in the spotter reports were localized but intense. One report logged 1.3 inches in 45 minutes with yard flooding. Another reported flash flooding along a corridor busy enough to push water across several intersections. The combination of roadway closures, rescue activity, and roof damage shows a storm that produced more than a single isolated hail core.

What Contractors Should Know

This event centered on the Tucson metro, with the heaviest field impacts reported near major road corridors and low-lying crossings. Old Nogales Highway, South Old Nogales Highway, 1st Street, River Road, Grant Road, Prince Road, and River Park Drive all appeared in the report stream. Crews should treat those corridors as priority canvass zones for interior water intrusion, roof edge damage, and loss reports tied to flash flooding.