Thunderstorm Winds
and Lightning...
the underated killers

Straight-line Winds...

  • Responsible for most thunderstorm wind damage.
  • Winds can reach 100 to 150 mph, or briefly equivalent to a Category 3 or 4 hurricane.
  • One type of straight line wind, the downburst, can cause damage equivalent to a strong tornado and can be extremely dangerous to aviation.

Lightning -- Nature's Fireworks...

  • All thunderstorms contain lightning.
  • Lightning bolts can travel 20 miles before striking the ground. It is safe to say that if you hear thunder, there is at least a remote chance that you can be struck by lightning.
  • Air near a lightning bolt can be heated to 50,000 degrees Fahrenheit, which is hotter than the surface of the sun.
  • Most lightning deaths occur when people are caught outdoors.
  • Most lightning casualties occur in the summer months and during the afternoon and early evening.
  • From 1959 through 1999, lightning killed 49 people in Wisconsin, giving Wisconsin a rank of 29th in the nation.
  • From 1959 through 1999, lightning injured 230 people in Wisconsin, giving Wisconsin a rank of 19th in the nation.
  • Since the southern half of Wisconsin experiences more thunderstorms during the year, most of the lightning-related fires, deaths, and injuries occur in southern Wisconsin.

In Wisconsin...

  • Wisconsin averages over 30 days each year with thunderstorms.
  • One of the country's worst thunderstorm windstorms occurred on July 4, 1977, in northern Wisconsin. Winds reached more than 115 mph in a swath over 150 miles long, flattening hundreds of thousands of acres of forest.
  • In 1998, thunderstorm winds were responsible for 1 death and 59 injuries in Wisconsin, mostly due to the widespread "derecho" thunderstorm wind event on May 30th and 31st across southern and central parts of the state. Maximum wind gusts ranged from 80 to 128 mph!!!
  • In 1999, thunderstorm winds resulted in 2 deaths, and 4 injuries in Wisconsin.
What You Can Do...

  • Know the county you live in. Severe weather warnings are issued on a county basis.
  • Check the weather forecast before leaving for extended periods outdoors.
  • If a storm is approaching, seek a sturdy shelter, and keep a NOAA Weather Radio with you.
  • Postpone outdoor activities if thunderstorms are imminent.
red ball Stay off the water if a thunderstorm approaches.

Don't take Severe Thunderstorm Warnings lightly!

URL: http://www.crh.noaa.gov/mkx/flyers/flyerstm.php

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