"The final measurement of the hailstone was 4 1/4 inches long, 2 1/4 inches tall, and 2 inches wide," said Michael Cantin, a National Weather Service meteorologist who confirmed the new state record. "According to hail report records for Hawaii kept back to 1950, the previous state record hailstone was 1 inch in diameter."
The record-setting hailstone was dropped by a supercell thunderstorm on the windward side of Oahu and produced large hail in Kaneohe and Kailua. Supercells are the largest, strongest and longest-lasting thunderstorms. Numerous reports of hail with diameters of 2 to 3 inches and greater were reported.
Only eight times since records began has hail of the size of a penny (diameter of 3/4 inch) or a quarter (one inch) been reported in Hawaii, and there is no record of hail larger than one inch in diameter. This is because ingredients to form hail larger than an inch are extremely rare.
Supercell thunderstorms and tornadoes are also both quite rare in Hawaii. The same hail-producing supercell produced a confirmed EF-0 tornado on March 9, with winds of 60-70 mph in Lanikai and Enchanted Lakes on Oahu.
A hailstone that hit Vivian, S.D., on July 23, 2010, holds the U.S record for having the largest diameter (8 inches) and for weighing the most (1.9 pounds). A hailstone in Aurora, Neb., on June 22, 2003, set the nation's record for the largest circumference (18.75 inches).
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