Monarch, MT Hail Storm – May 2026

Monarch, MT experienced a concluded hail event on May 13, 2026, producing up to 1.05-inch hail across the metro and generating a long sequence of NWS warning-area alerts. The storm moved through late afternoon into early evening with radar-detected hail signatures and multiple warning polygons covering the same corridor.

What Happened

Late afternoon into early evening on May 13, NWS issued 17 warning-area alerts for the Monarch metro between 2:46 PM MDT and 10:03 PM MDT. Sixteen alerts were issued as NWS warning only products indicating expected hail in the warning area, many listing 0.75-inch hail as the forecast size. Several periodic alerts registered no hail in the text, signaling circulations or updates to the warning polygon rather than verified hail at those times. Dual-polarization radar detected a focused hail signature at 6:27 PM MDT, recorded by radar-derived hail products as 1.00 inch. Aggregated monitoring shows a maximum measured value of 1.05 inch for the event. The storm is concluded.

Damage Assessment

The alert sequence was dominated by 0.75-inch detections across multiple warnings, with isolated radar returns above one inch. Hail of three-quarter-inch size commonly produces paint dents on unprotected vehicles and can bruise or granule-loss smaller areas on asphalt roofing. Isolated readings above one inch increase the chance of broken skylights, dented metal surfaces, and more pronounced shingle granule loss that can shorten remaining service life on older roofs.

Damage exposure is concentrated within the NWS warning areas that tracked the storm through Monarch and adjacent addresses. Where hail accumulations or repeated impacts occurred, contractors should expect localized roof shingle compromise, dents to parked vehicles, and possible impact to exterior fixtures such as air-conditioning units and soft-wood trim. No public spotter-verified damage reports are included in this summary; field inspection is required to determine actual loss at individual properties.

What Contractors Should Know

Begin with a triage inspection focused on vehicle lots, rooftops facing the storm track, and exterior mechanical equipment. Prioritize safety: use fall protection on pitched roofs, verify structural soundness before walking, and avoid ladder work in wet or unstable conditions. Photograph damage from multiple angles, note the time of inspection, and mark GPS locations or addresses for each damaged unit.

Document granular evidence and immediate mitigation. Capture close-ups of dent patterns, shingle granule loss, and any cracked glazing. Preserve any hail fragments if available and measure diameters next to a ruler for insurer records. Provide temporary covers where water intrusion is possible and schedule definitive repairs according to observed damage severity and local permitting. Coordinate with property managers and insurers before large-scale roof work.