Showing posts with label Thunderstorms. Show all posts
Showing posts with label Thunderstorms. Show all posts

Tuesday, February 24, 2009

Lightning The Underrated Killer!

Every second on Earth around 45 bolts of lightning occur. That amounts to a staggering 1.4 billion flashes of lightning per year. Of these total bolts about 20%actually hit the Earth’s surface meaning there are nearly 280 million cloud to ground or ground to cloud lightning sbolt from the blue,trikes each year. With a tremendous amount of electricity, an average of one terawatt or one trillion watts per bolt, and an extremely high temperature, around 50,000°F, it is no wonder lightning is such a great threat to life and property. The greatest know loss of life from one lightning strike was in Brescia, Italy in 1769 when 3000 people lost their lives because lightning struck a church containing 100 tons of gunpowder that resulted in a huge explosion destroying a sixth of the city.(source Wikipedia) To see how lightning strikes are distributed around the world, take a look at the image below. Notice there is a great concentration of lightning near the equatorial regions of the world where thunderstorms are very common. The lightning capital of the US would be the peninsula of Florida where 6 to 9 months of the year sea breeze fronts collide across the center of the State causing thunderstorms to develop most afternoons.



On average lightning kills 66 Americans each year. This number is greater than that caused from hurricanes and tornadoes. Here are some interesting statistics of lightning victims in 2007.

98% were outside

89% were male

30% were males between the ages of 20-25

25% were standing under a tree

25% occurred on or near the water

So what can we do to keep our selves safe during a thunderstorm? Some easy rules to follow would include finding indoor sturdy shelter during a thunderstorm. Stay away from windows. If you are on the golf course and hear thunder, return to the club house immediately. Standing in an open field holding a metal club makes you a lightning rod. If you are caught outdoors and cannot make it to a shelter the best advice is to crouch down, tuck your head, cover your ears, and only have your toes touching the ground. If you lay flat on the surface then you have a much better chance of being struck indirectly form lightning from an underground current. For more on lightning safety click here. When is it no longer safe to be outside? If you can hear thunder, your best bet is to move inside. To determine how far away lightning is from your location, count the seconds in between the lightning bolt and thunder. For every five seconds you count, a distance of one mile passes. So if you see a lightning bolt and 30 seconds later you hear the thunder, the lightning was approximately 6 miles away. Lightning has been known to strike and cause injury or death up to 10 miles away from the parent storm. This type of strike is known as a “Bolt From The Blue.” So staying inside 30 minutes after you hear the last clap of thunder is the best way to keep you and you family safe.



While lightning can be a beautiful sight, it is best to take precautions to insure your safety during natures underrated killer.

Monday, February 16, 2009

Valentine's Night Storm........


For all those lovers of exciting weather Cupid shot his arrow into the atmosphere and whipped up some elevated thunderstorms Valentine’s Night bringing a vivid lightning show and small hail to parts of East Texas. The lightning shots you see here were taken from my front porch as a strong storm moved out of Eastern Henderson County into Smith County.




This storm produced a large amount of small hail, covering the ground and causing hazardous travel along 346 from Flint to Whitehouse. The largest hailstone I found was penny size which technically is severe near the intersection of 346 and Oakbrook. These storms fired with a combination of many atmospheric conditions which came together over East Texas.



First, in the mid levels of the atmosphere a weak disturbance was entering West Texas causing the winds to diverge over East Texas. This causes the air to rise which could lead to clouds and precipitation. Second, a strong jet stream in the upper level of the atmosphere was moving just to our south. This put East Texas in what we call the left exit region of the jet stream which also adds in lifting the air.


Third, strong wind shear was noted in the atmosphere from 6,000’ to 30,000’. This will help aid in thunderstorm development by pushing the rain cooled air downstream, away from the storms updraft allowing the storm to become stronger.





The only thing missing for thunderstorm development, moisture. The low levels of the atmosphere where we normally find the moisture needed for thunderstorm development were too dry for surface based storm development. However, in the lower mid levels of the atmosphere a thin layer of moisture was moving into East Texas. This was all that was needed to help fire what we call elevated thunderstorms. Since the low levels of the atmosphere were dry, we were giving a vivid lightning storm with great visibility, giving many photo opportunities.





Tuesday, February 3, 2009

Snow??????




Some places across East Texas awoke to what appeared to be snow yesterday. But if you were awake during the event, and most people were, you would know that a hail storm effected parts of the area Sunday night. I line of thunderstorms erupted ahead of a fast moving cold front Sunday night producing gusty winds and lots of small hail. We did receive reports of up to golf ball size hail in Montalba but most of the storms produced pea size hail. A storm that formed along the Rusk Panola county line produced a heavy dose of pea size hail which lasted for about 20 minutes. This caused an accumulation of small hail in some areas to reach 10” in depth. Now this occurs occasionally in western states but an accumulating hail even is very rare for East Texas. A big thank you to Rusty Nix for sending me photos of the hail accumulation.