Encyclopedia Dubuque
"Encyclopedia Dubuque is the online authority for all things Dubuque, written by the people who know the city best.”
Marshall Cohen—researcher and producer, CNN
Affiliated with the Local History Network of the State Historical Society of Iowa, and the Iowa Museum Association.
HAILSTONES
HAILSTONES. Hailstones are balls of ice that grow as they are held up by updrafts that blow upwards in thunderstorms. The updrafts carry droplets of supercooled water - water at a below freezing temperature - but not yet ice. The supercooled water droplets hit the balls of ice and freeze causing the hailstones to grow. The faster the updraft, the bigger the stones can grow. Most hailstones are smaller in diameter than a dime, but stones weighing more than a pound have been recorded.
This picture shows hailstones which fell at Dubuque on June 16, 1882. They weighed between 3-15 ounces with diameters from 2-5 inches.