Big Timber, MT Hail Storm – June 2025

What Happened

A severe hail storm moved through Big Timber, Montana, on June 14, 2025, with a peak confirmed hail size of 2 inches and a long run of NWS alert areas through the evening and into the early morning hours. The storm produced radar-derived hail estimates, spotter-verified reports, and one field report based on a photo of hail held in a hand.

The first alert came at 4:34 PM MDT with 1-inch hail. By 5:18 PM MDT, the hail threat had increased to 1.25 inches. A second 1.25-inch alert followed at 5:44 PM MDT using dual-polarization radar. The storm then strengthened again in the early evening. At 6:26 PM MDT, the hail size reached 2 inches in a radar and spotter-verified alert.

Additional 2-inch detections followed at 6:43 PM MDT and 7:07 PM MDT. One 1.5-inch alert came at 6:45 PM MDT from the warning area alone, then radar returned to a 1-inch hail estimate at 6:49 PM MDT. By 7:35 PM MDT and 7:39 PM MDT, the storm was still producing 1.25-inch and 1-inch hail estimates from dual-polarization radar. Another 2-inch alert arrived at 7:56 PM MDT with spotter support.

Later alerts kept the hail threat in the 1.5-inch to 1.25-inch range through 8:38 PM MDT. The warning area remained active into the night, with additional NWS alert areas at 10:23 PM MDT, 10:58 PM MDT, 11:21 PM MDT, 11:25 PM MDT, 11:43 PM MDT, and 1:17 AM MDT. A spotter-verified field report came in at 11:45 PM MDT, describing hail estimated from a photo of stones in the palm of a hand.

Damage Assessment

The field report picture points to a localized hail swath with measurable surface impact, but the publicly available reports are limited. The strongest ground truth came from the 11:45 PM MDT spotter-verified report, which placed the hail at 1 inch based on the photo evidence. Earlier and later radar and spotter alerts documented larger stones in the same storm sequence, including multiple 2-inch detections.

This was not a single short-lived burst. The alert stream shows repeated hail signals across several hours, with swings between 1 inch, 1.25 inches, 1.5 inches, and 2 inches. That pattern fits a storm that produced pockets of stronger hail cores as it moved through and re-intensified within the warning area.

For Big Timber, the most useful takeaway is the spread between radar-derived hail sizes and the limited field report set. The storm delivered verified hail at multiple points in the evening, but the public report count is not large enough to map the full ground impact without more site-level observation. Roof, vehicle, and crop inspection would have been most important in the corridor where the 2-inch and 1.5-inch alerts overlapped.

The local storm report tied to a hail photo supports the smaller end of the observed range at the point of that observation. It does not erase the larger hail detections. It shows that hail size varied across the event and likely across the warning area.