Hail Cannons

Even with no supporting scientific data, many still believe loud noises can disrupt hail development in thunderstorm.  Hoping to prevent crop loss from hail, some civilizations still ring church bells when weather threatens.  Fatal lightning strikes prompted many European countries to outlaw this practice. 

Luigi Bombicci was a mineralogist and chairman of the Department of Mineralogy at the University of Bologna.  In certain circles he is credited with originating the theory of loud noises and hail prevention.  In 1880, he introduced his ideas on hail formation and negation by hail canons.

Early hail canons were constructed from old locomotive smoke stacks mounted to a large block of wood.  Black powder created the explosion and the smoke stack directed the potentially hail stopping sound wave toward the sky.  Anti-hail rockets with 800 grams of dynamite replaced hail canons in the early 20th century.

The last decade has seen an increase in hail cannon usage.  Hail canon prices begin at $60,000.  They claim the use acetylene and air produces sound shockwaves which disrupt hailstones during their growth stage.  You can see the 20-foot tall hail canons and hear their every 6-second blast on California farms in the Central Valley.

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