Quizzes & Puzzles4 mins ago
Rain from nowhere?
The other day I was playing cricket under an absolutely cloudless sky, no clouds whatever (one of the few days this year) when it started to rain. Not enough for the game to be stopped but definitely a light wetting which lasted for perhaps, five or six minutes. Can anyone explain? maybe something to do with humidity or "dew point" or some such.
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For more on marking an answer as the "Best Answer", please visit our FAQ.In certain weather conditions, you may recall seeing rain that doesn't reach the ground. It's called virga and, generally, is caused by rain falling and evaporating before reaching the earth's surface. Similar to this is the phenomena of rain falling at one place but being carried fairly long distances by shearing winds that need not be of great velocity and allowing the rain to reach the surface along the upper winds route. Very uncommon, since the action of the shearing wind tends to evaporate the rain, but does, as you've experienced, happen.
Alternately, you don't indicate how much of the sky dome you could see, but as an airline pilot for many years I, and others, learned hard lessons by flying underneath the overhanging 'anvil head' of a cumulo-nimbus associated thunderstorm even though several miles from the actual storm center as depicted on radar. The hail that comes from such a storm, if well developed, can be spewed out of the anvil head and fall many mile from the visual storm. Aircraft have been damaged from this unexpected hail fall. Such hail could be carried for several miles and melt into rain drops before reaching the surface...
Alternately, you don't indicate how much of the sky dome you could see, but as an airline pilot for many years I, and others, learned hard lessons by flying underneath the overhanging 'anvil head' of a cumulo-nimbus associated thunderstorm even though several miles from the actual storm center as depicted on radar. The hail that comes from such a storm, if well developed, can be spewed out of the anvil head and fall many mile from the visual storm. Aircraft have been damaged from this unexpected hail fall. Such hail could be carried for several miles and melt into rain drops before reaching the surface...
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There's always moisture in the air. Even on a cloudless day. Changes in air pressure and temperature can allow this moisture to form microscopic droplets that start to fall. As they descend, they pick up more moisture, and the droplets increase in size and can become quite bug raindrops. It isn't necessary for a cloud to have formed first. I've even experienced a shower of hailstones in the Saudi desert under similar circumstances. And it was 125 F� in the shade at the time!