Frederick, SD Hail Storm – July 2025

Frederick, SD saw a concluded severe hail event on July 22, 2025. The storm produced a verified maximum hail size of 2 inches across four NWS alert areas.

What Happened

The first hail alert came at 10:26 AM CDT with 1-inch hail detected by dual-polarization radar confidence. The storm returned in the afternoon with a stronger hail signature. At 4:12 PM CDT, radar confidence supported 2-inch hail.

Two more alerts followed in the evening. At 7:27 PM CDT, the hail threat was again centered on 1-inch stones. Four minutes later, at 7:31 PM CDT, the hail estimate increased to 1.5 inches. The alert sequence shows repeated hail development through the day, with the strongest verified size occurring in late afternoon.

The storm remained a multi-zone hail producer rather than a single short-lived burst. The warning area expanded and shifted across the day as the hail core evolved. The radar-derived hail sizes were consistent with a storm that produced intermittent but severe hail impacts across more than one corridor.

Damage Assessment

Hail up to 2 inches can damage roofs, vents, soft metal, window screens, and exterior trim. It can also leave visible impact marks on siding, gutters, and paint. Smaller hail in the 1 to 1.5 inch range can still create scattered roof loss, bruised shingles, and dents on exposed metal surfaces.

For contractors, the mixed hail sizes matter. A 1-inch report in the morning does not rule out larger impacts later in the day. The 2-inch peak came from a later alert, which means property conditions may vary across the same town depending on which part of the storm path a structure sat under.

Field crews should expect uneven damage patterns. One block may show only cosmetic metal dents while another may have roof slope loss, ridge cap impact, or broken exterior fixtures. Document all elevations, roof planes, and soft metal components separately. Pay close attention to north- and west-facing exposures, skylights, and older asphalt roofs with prior wear.

This event also calls for close photo and measurement discipline. Compare roof slopes, note shingle granule loss, and record any collateral damage to gutters, downspouts, HVAC fins, or vehicle panels. Use the hail range, not a single size, when setting inspection priorities.

What Contractors Should Know

Start with the late afternoon hail reports and work backward. The 4:12 PM CDT 2-inch alert is the anchor point for this event, but the morning and evening alerts show the storm produced repeated hail. That makes mixed-condition properties likely inside the broader warning area. Crews should expect some homes to show only light impact while nearby structures carry more obvious roof and metal damage.

Prioritize roofs with steep slopes, aging asphalt, and exposed accessories. Check penetrations, ridge vents, soft metals, and any ancillary structures in the same path. In a multi-zone hail event, outbuildings, patios, mailboxes, and fencing often show damage where the main roof appears less affected. Keep inspection notes tied to time, address, and surface type so the field record stays consistent across the storm footprint.