Flagstaff, AZ Hail Storm – July 2026

Flagstaff, AZ recorded a multi-zone hail event on July 20, 2026, with radar detections showing a peak signature of 2.28 inches. The storm evolved through the afternoon and produced repeated NWS alerts across the metro.

What Happened

The event unfolded in the mid- to late-afternoon. NWS issued ten consecutive alerts between 1:21 PM and 4:00 PM. Several alerts were radar-detected via dual-polarization NEXRAD hail detection. Others were issued as NWS warning only alerts.

Sequence of NWS alerts and detections:

• 1:21 PM MST – 1.07-inch hail – radar-detected via dual-polarization NEXRAD
• 1:48 PM MST – 1.11-inch hail – radar-detected via dual-polarization NEXRAD
• 2:15 PM MST – 1.50-inch hail – radar-detected via dual-polarization NEXRAD
• 2:25 PM MST – 1.44-inch hail – radar-detected via dual-polarization NEXRAD
• 2:59 PM MST – 1.00-inch hail – NWS warning only
• 3:04 PM MST – 1.00-inch hail – NWS warning only
• 3:26 PM MST – 1.00-inch hail – NWS warning only
• 3:29 PM MST – 1.00-inch hail – NWS warning only
• 3:33 PM MST – 1.38-inch hail – radar-detected via dual-polarization NEXRAD
• 4:00 PM MST – 2.28-inch hail – radar-detected via dual-polarization NEXRAD

Radar-detected alerts showed evolving hail signatures that intensified through the afternoon. The final radar detection at 4:00 PM produced the largest radar hail signature for the event. The pattern shows repeated cells traversing the metro, producing multiple alert updates in a three-hour span.

Damage Assessment

Hail signatures recorded during the event ranged from roughly 1.0 inch up to the peak radar signature. Hail at or above 1.0 inch can crack unprotected glass, dent vehicle panels, and damage rooftop materials when driven by wind. Hail exceeding roughly 1.5 inches raises the risk of broken skylights, significant siding damage on exposed walls, and more pronounced vehicle windshield and sunroof breakage.

A 2-inch-plus hail signature indicates a strong potential for widespread moderate to severe impact on vehicles, exposed HVAC units, and asphalt shingle roofing on homes with older or marginal roofing materials. Localized impact is likely to vary by exposure, roofing age, and whether vehicles were parked under cover. Field verification is required to determine actual damage locations and severity within the metro.

What Contractors Should Know

Inspection teams should prioritize residential neighborhoods and commercial lots near the storm track for initial canvassing. Start with areas that reported the largest radar signatures and work outward into zones that received repeated NWS warnings only. Photo documentation should include scale references and exact address or GPS coordinates for each damaged asset.