weather- rules of thumb.
Just to add a little helpful meteorology. Air movement is counterclockwise around a low pressure area, and clockwise around a high. With the passage of a front, the wind always changes in speed and direction. When you see the surrounding isobars around a low or a high pressure area, the closer they are together, the larger the wind gradient. And finally, if you see an anvil shaped cumulonimbus, the storm is usually traveling in the direction the anvil is pointing. The anvil is formed by the upper level stronger winds "knocking" the top of the thunderstorm downwind, and often will emit hail into the "clear" zone beneath the anvil. The correct formula for estimating how far away lightning is, is when you see the lightning count the number of seconds it takes for the thunder to reach you. 5 seconds = i mile, not 5 seconds = 5 miles as some people believe. Since lightning can strike up to 10 miles away, we're dealing with the time from lightning to thunder of 50 seconds!!!!! ( Note: due to the curvature of the earth, a 6 foot man at sea level, only sees the horizon seven miles away. Of course a 40,000 ft storm cloud is visible a long ways away.)
|
06-11-2008, 07:30 PM
Threaded Mode