The oldest storm in this library lasted two days. Over June 13 and 14, 1984, hail fell across Adams, Arapahoe, Denver and Jefferson counties, with stones up to 3 inches in the NCEI record and 24 reports in the Front Range counties. NCEI lists 20 people injured.
RMIIA, the Rocky Mountain insurance industry association, puts insured losses at $276.7 million in 1984 dollars. Its adjusted figures do not agree with each other: the hail page gives $879 million in 2026 dollars, while its catastrophe page gives $765 million and $864.9 million in 2025 dollars in two different tables. NOAA counts the storm system, June 13 to 17 and across every state it touched, among its billion-dollar disasters.
Hail history for the counties hit
Significant Colorado storms around 1984
- July 11, 1990: hail to 2.75 in., $625 million (1990 dollars) insured
- May 30, 1991: hail to 2.5 in., $100 million (1991 dollars) insured
- October 1, 1994: hail to 2 in., $225 million (1994 dollars) insured
- May 22, 1996: hail to 2 in., $122 million (1996 dollars) insured
- The full Colorado storm table
Sources: Hail Damage and Statistics: Colorado's Most Costly Hail Storms (Rocky Mountain Insurance Information Association (RMIIA, now RMIA)); NOAA NCEI Storm Events Database (NOAA National Centers for Environmental Information).
