Thornton hail storm history
Adams County·NOAA NCEI Storm Events Database·~75-day publication lag
Thornton, located in Adams County, experienced 2 documented hail events of 1 inch or larger over the past 10 years, with the largest recorded event producing 2-inch hail. The city sits on the Colorado Front Range, where afternoon convective storms tracking northeast from the Rocky Mountains create conditions favorable for hail formation.
Hail risk in Thornton peaks between May and July, with secondary risk in April and August. Most significant events occur in the afternoon and early evening between 2 p.m. and 7 p.m. Mountain Time, when atmospheric instability is greatest along the Front Range corridor.
Annual frequency — last 10 years
When hail hits — monthly pattern
Avg events per month · all years · NOAA data
All recorded hail events
Of 2 recorded events, 1 (50%) reached 1.5" or larger — the threshold for likely functional damage on standard asphalt shingles.
The report was via mping.
Thornton's low event count reflects both genuine meteorological patterns and NOAA reporting density limitations in Adams County. Storms producing hail smaller than 1 inch may not be formally recorded in the National Weather Service database, so actual hail impacts may exceed documented events.
NOAA Storm Events Database source