Most fence posts are treated with a wood. preservative to increase their service life, but the. installation method can affect the actual life of. the fence post. These pages will serve as a quick. guide to installing preservative-treated fence. posts for the greatest serviceable life.
The entire lifetime of a thunderstorm can vary. Typical afternoon thun â¦ derstorms in the summer usually consist of just 1 cell, thus lasts 20-30 minutes. Severe thunderstorms can consist of numerous cells, and last several hours.
A thunderstorm will form first and develop toward the region that has the best combination of: high PBL moisture, low convective inhibition, CAPE and lifting mechanisms. The difference between a thunderstorm and a severe thunderstorm is the wind field. For a severe thunderstorm, the ingredients that must be present are moisture, instability, lift and strong speed and directional storm relative wind shear. Ideally, wind will have a veering directional change of 60 degrees or more from the surface to 700 millibars, upper level winds will be greater than 70 knots, and the 850 to 700 mb winds (low level jet) will be 25 knots or greater.