Severe Storm exam - Assignment Example

It is because of this movement that a derecho is referred to as a; “straight-line wind damage”. Derecho winds originate from downbursts. They possess almost similar characteristics. The inherent difference is that; derechos assume a curved shape, while downbursts maintain horizontal dimensions of approximately 4 to 6 miles. Winds in a derecho have must be greater than 57mph for them to be considered as severe wind gusts (according to the National Weather Service). There are three different types of derechos: serial derencho, progressive derencho, and boundary waters-Canadian derencho.

The serial derencho originates from multiple bow echoes in a wide squall line. The progressive derecho originates from single bow echoes in short line of winds and thunderstorms. The Boundary Waters-Canadian Derecho develops from a narrow progressive derecho in the bow echo system. The ‘derecho triangle’ is extensive; from Minneapolis to Dallas to Pittsburgh. Derechos occur mostly in the late spring and summer seasons. They take place along two axes: the extensive “corn-belt” region; from the upper Mississippi Valley to the Ohio Valley and from the mid Mississippi Valley to the southern plains.

They are not common during autumn and winter. If they occur during these seasons, they are experienced in eastern Texas to the south eastern states. Isolated derecho have been experienced in the western United States during the spring. In the mid-Atlantic, derechos are mostly experienced in the warm season. They take place on the fringes of great heat waves. Large-scale heat waves provide conditions that are conducive for the development of derechos. The heat waves and derechos are linked by an Elevated Mixed Layer (EML); mid-tropospheric layer of air that develops over the elevated arid terrain.

Emls exhibit steep reductions in temperature with height. These temperature differentials enhance