Kenny had wanted to see a thunderstorm over the Gulf of Mexico when we went to Navarre Beach on July 28, 2009; he got his wish! Just minutes after I took this photo, these kids had to get out of the water because it began to lightning. It is hard to judge the speed of a storm out over the water, so it caught up with us before we could get off the island. The wind blew the sand from the beach over the road, it blasted the car! The rain and wind were so strong we had to pull over before getting on the bridge.
means "piled up rain cloud". These clouds are the "bad boys" of the cloud types, towering up to 7 miles high, capable of delivering pounding rain, downdraft winds, hail, and even tornadoes. The vertical winds inside these storms can reach 100 miles per hour. Hail forms when small ice crystals are lifted up inside the cloud and begin to grow, much like the layers of an onion. When the hailstone gets heavy enough, it will fall to the ground at up to 120 mph! Airline pilots will avoid these types of clouds at all cost. We once were flown miles out of our normal flight path and then under the cloud to avoid being in the worst of the storm. It was still a very bumpy ride, the passengers applauded when we touched down in Knoxville!
Thunderstorms produce lightning because of the electrical charges produced in the clouds. The clouds become electrically charged due to static electricity that builds up when the water molecules are bounced around inside the cloud. The stronger the updraft winds, the more lightning. The negative electrical charge builds up at the base of the cloud and a positive charge builds up on the ground. Since positive and negative charges attract they meet to form a bolt of lightning. Sometimes when lightning is about to strike people may feel the hair stand up on their arms or the back of their neck because of the positive charges; that should be taken as a warning to seek shelter immediately. The tallest objects around are most likely to be struck, that is why people should never stand under a tree or be up on a mountain top during a thunderstorm. Lightning is 5 times hotter than the surface of the sun (54,000 degrees F), that sudden heat causes a rapid expansion of the air which results in the sound of thunder. The distance of lightning can be calculated by counting how many seconds it takes to hear the thunder after seeing a bolt of lightning, 5 seconds = 1 mile. Thunderstorms often preceed a rapid change in the weather if they are ushered in by an advancing cold front or warm front. Storms are associated with low pressure systems, the stronger the storm, the lower the barometric pressure. Hurricane Katrina had the 3rd lowest pressure readings ever recorded at 27.11 inches of mercury. Low pressure is caused by rising warm air, it is a bit difficult to breathe during a hurricane because the air pressure is so low. Low pressure systems, which move counter-clockwise, bring rain and bad weather, they are indicated by a red "L" on a weather map. High pressure systems on the other hand bring nice weather. The cooler, drier air sinks, it moves in a clockwise pattern. These systems are indicated by a blue "H" on a weather map. This is the Japanese Peace Bell in the park at the Civic Center in Oak Ridge. For more information on thunderstorms, see: Thunderstorm info
