Waupun, WI Hail Storm – September 2026

A severe hail storm tracked through Waupun, Wisconsin on September 3, 2026, producing 3.29-inch stones during a late-night convective cluster. The event generated multiple NWS warnings and a series of radar-detected hail signatures between late evening and the early morning hours.

What Happened

The storm sequence began in the late evening and intensified over Dodge County. NWS products and public alerts totaled 20 items for the Waupun area spanning the day and overnight window. Dual-polarization NEXRAD flagged repeated hail signatures beginning shortly before 11:00 PM CDT and continuing into the early morning, while NWS warning-only messages bracketed the larger convective period.

Local spotters provided ground observations during the core of the event. At 11:32 PM CDT a relay on NWSChat recorded a golf ball-sized hail observation. Shortly after midnight, an mPING submission logged a half dollar-sized report, and another mPING submission just before 11:30 PM reported quarter-sized hail. Those spotter-verified observations were received while radar hail detections were active across the same corridor.

The sequence included alternating radar-derived hail detections and NWS-only notifications through roughly 2:40 AM CDT, indicating a migrating cluster with intermittent intensification. Radar detections and spotter reports overlap in time and place, establishing both the nocturnal timing and the localized nature of the strongest hail cores.

Damage Assessment

Local storm reports contain three spotter-verified hail observations within the Waupun area during the overnight period. The NWSChat relay at 11:32 PM CDT and two mPING submissions between 11:28 PM CDT and 12:31 AM CDT are the primary ground-truth records tied to this event.

Radar indicates a broader hail footprint than the concentrated cluster of spotter reports. Surface impacts therefore appear focused on the corridor where spotters were active. Field observations and radar-detected hail signatures suggest vehicle denting and soft-metal damage are the most likely observed outcomes in affected neighborhoods and roadside exposures, with isolated shingle abrasion possible where hail concentration was highest.

No additional verified structural collapse or large-scale tree damage was reported in the ground-truth set provided. Claims handlers and inspectors should reconcile the three spotter observations with property and vehicle assessments along the storm track to map reported impacts to address locations.

What Contractors Should Know

Prioritize inspections along the late-night track that produced spotter reports. Begin with vehicles and exposed soft metals, then move to roof systems and gutters. Photograph all findings with time-stamped images and capture orientation and proximity to the street; the narrow cluster of spotter reports means damage may be nonuniform across short distances.