Upton, WY Hail Storm – September 2025

Upton, WY saw a multi-zone hail storm on September 12, 2025, with peak confirmed hail reaching 2.5 inches. The storm produced four separate NWS alert areas through the afternoon and evening.

What Happened

The first alert came at 4:03 PM MDT, with 1.5-inch hail supported by dual-polarization radar confidence. Two more alert areas followed at 4:39 PM MDT and 5:09 PM MDT, each tied to 1.75-inch hail and NWS warning-only confidence. A later alert area was issued at 8:20 PM MDT with 2.5-inch hail.

The sequence shows repeated hail production across the same general storm track from late afternoon into early evening. The storm was concluded by the time of this report.

Damage Assessment

Hail in the 1.5-inch to 1.75-inch range commonly damages asphalt shingles, soft metal trim, vents, gutters, and exposed HVAC fins. At 2.5 inches, impact force rises sharply. Roof slopes, skylight covers, vinyl siding, window screens, and lightweight exterior fixtures can show direct strike damage. Vehicles parked outside are also at risk for denting and broken glass.

In a multi-zone storm like this, damage can vary from one block to the next. Roofs on the edge of the warning area may show lighter impact patterns, while structures closer to the hail core can carry heavier losses. The strongest hail within the storm did not arrive all at once. It built through several alert areas over the course of the afternoon.

What Contractors Should Know

Start with roofing, HVAC, and vehicle exposures. On homes, check ridge caps, pipe boots, soft metal flashing, drip edge, and gutter seams. Granule loss can be uneven after hail in the 1.5-inch to 2.5-inch range, so walk each slope and note directional impact. Screened enclosures, painted fascia, and window wraps can show marks even when the roof appears only lightly affected.

For field work, separate the earliest alert areas from the later, larger hail. The 4:03 PM MDT alert area carried 1.5-inch hail with radar confidence. The 8:20 PM MDT alert area carried the largest hail in the event. That spread matters when you compare loss patterns across roofs, vehicles, and outbuildings in and around Upton.

Keep your canvass notes tied to location and time. If you are working claims, document where the hail was heaviest and which structures sit inside the strongest part of the storm path. The 2.5-inch peak supports a detailed exterior review, especially on roofs with prior wear or older asphalt systems.

For exact hail track data, review the Strike Map.