In my column of February 23, I explained how a warm weather thunderstorm develops. We get a lot of them during from March through September, with the worst ones usually occurring in April, May and June. Folks generally are aware that the tornados they sometimes spawn can be killers, but too many people underestimate the terrible strength and danger of a severe thunderstorm by itself.
According to data from the National Weather Service, 50-70 thunderstorms a year develop here in East Texas, only exceeded by Florida and some places along the eastern Gulf Coast. Danger comes from lightning, flash flooding, hail, straight-line winds and tornadoes. Outdoor recreationists, particularly those on golf courses, baseball diamonds, soccer fields and lakes, as well as farmers in open fields, are at great risk from lightning as severe weather develops. Flash flooding from intense downpours can quickly inundate roads, intersections and underpasses. Since it only takes about 18 inches of water to float a car, those who drive into water during storms are at great risk and every year some drown in their cars or are swept away when they attempt to go from their vehicle to high ground.
Although not rotating like a tornado, very strong winds occur before and during thunderstorms. Wind gusts preceding the storm descend from the blackening storm clouds and race across the ground in a straight line. They can be greater than 100 mph and cause extensive damage. These downbursts of wind are extremely hazardous to aircraft and crashes have occurred at or near airports as planes, small and large alike, were slammed into the ground by the brief but devastating winds.
Tornados do sometimes come from intense thunderstorms, but whether the wind that rips off your roof, flattens your chicken houses and wraps sheet metal around trees like wet tissue paper comes from a tornado or ÒmerelyÓ straight-line winds is only of interest to meteorologists. The results are the same.
Intense downpours commonly occur ahead of thunderstorms. Rain pours in torrents from these so called ÒcloudburstsÓ and flash flooding occurs, filling and overflowing streams, dry washes and other low-lying areas. Winds within intense, developing and mature thunderstorms are very high, rushing up, down and around. Thunderheads often tower higher than 50,000 feet into the air, their tops made of ice crystals, middles composed of a mix of rain, snow, sleet and hail. Hail can produce extensive damage to livestock, crops, roofs, windows and vehicles. Last week intense storms accompanied by at least two tornadoes, swept through Nacogdoches, Lufkin, Madisonville and Garrison and surrounding areas. At our house just a mile north of Nacogdoches, the wind gusted to 35 mph and 1 1/2 inch hail fell. In the vicinity of Chireno, hail the size of small tomatoes fell. Hail that size not only dents cars, it puts lives at risk.
Any time hail 3/4 inch or larger is falling, particularly if it is accompanied by high winds, a serious danger exists and people ought to take cover away from windows and doors in the sturdiest part of their house, such as an interior bathroom or cellar until the event passes.
Lightning occurs in all thunderstorms, flashing through the clouds and from cloud to ground. Staggeringly powerful, the average lightning bolt could light a 100-watt bulb for about three months. As the gigantic electrical spark we call lightning lashes out, the air through which it passes is heated to 50,000 degrees Fahrenheit, hotter than the surface of the sun, causing waves that we hear as cracks, crashes and rumbling thunder. People in the open, under lone trees, in boats or swimming are at great risk. Needless to say, someone struck directly by a lightning bolt that generally carries 150 million volts and 125 thousand amps of electricity is unlikely to survive the experience.
Learn natureÕs warning signs and invest in a weather radio that automatically alerts you with a piercing alarm transmitted by the National Weather Service. Clouds towering and darkening in the sky on warm, humid afternoons, thunder and lightning intensifying and moving closer and high winds are all danger signals. Often the clouds take on a yellowish or greenish tint. When these indicators occur in conjunction with 3/4 inch or larger hail, get to a safe location. DonÕt take chances. Remember - nature doesnÕt care if you are complacent. Natural forces are powerful, potentially deadly and unforgiving. Stay alert, prepared and alive this storm season in East TexasÕ fields and forests and in two weeks read the last portion of this series which will give you information on preparedness and storm survival.