Thunderstorms

There are several types of Thunderstorms for our area. Squall lines-associated with fronts, "Popcorn variety cells that pop up out of nowhere along a frontal boundary, and then occasionally we get Supercells. These usually form on their own and become raging machines as there is no rain or interference around the South and East sides to occlude their fuel, warm air and moisture. These cells can cover an area as large as 2000 square miles and travel as fast as 70 mph for hours. These are the ones of main concern, as they will produce the damaging winds, outflows/gust fronts in excess of 70 mph, microbursts with winds in excess of 150 mph, very large hail, and tornadoes. The squall lines are also an issue here too. They can produce supercells on the Southern end of the line where the fuel is, or in breaks in the squall line where they can get good inflow, uncooled by the advancing rain. A lot of them become Derechos also. A Derecho is when the squall line gets a boost from winds and begins to bow out along the middle of the line mostly, forming a bow shape like so- ) (a bow) usually moving from West to East. The center of the bow will have much faster winds, but is usually short lived as it pushes itself out to the point it separates from the line and loses its backing. The "popcorn" variety of cells are usually harmless if they don't grow into anything. They just come and go kind of like fireworks in the sky, appearing for a short burst, then fading out.

Cloud formations will give a good clue as to what you will see. This is a cumulonimbus cloud, with a shearing anvil, moving towards the camera. This is a large thunderstorm aerial shot from probably 30-40,000 feet up. Note that from the ground, you wont see much of this, but if you see this formation from a distance, keep an eye on it. See the little plumes in center of pic going up underneath the anvil? That is the leading edge of the storm. This is where the fuel is coming in and feeding the "machine":

They will gradually go higher and get overtaken by the main tower, and new ones will rise up, thus, a machine, repeating this cycle. Here is an explanation of this process:

Also you will notice the flat top of the anvil. This is our cap, where the atmosphere is stopping the upward build of the cell. The cap may erode away, and with the cycle, the leading towers can generate higher, eventually punching through the cap with enough lift, thus making the storm stronger. The Jarrell cell came into an area of no cap and topped out at 58,000 feet.

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