Severe Thunderstorm Warning Hail Criterion to Change

The National Weather Service in Billings, along with all National Weather Service offices across the Western United States, will change it's Severe Thunderstorm Warning hail criterion on June 1. The hail criterion will be raised from 3/4" to 1" diameter. This change is in response to research done across other portions of the country that significant property damage does not occur until hailstone sizes reach 1" in diameter. The Severe Thunderstorm Warning wind criterion will remain the same at 58 mph (50 knots). Information for organized strong, but less than severe, thunderstorms will be provided by a Significant Weather Advisory.

Click HERE to view a short video with more details on the background and implementation of this change.

Questions or comments about this change should be directed to Tom Frieders, the Warning Coordination Meteorologist at the Billings forecast office by email HERE or by calling (406) 652-0851.