Where did the phrase: "Out of the (clear) Blue" come from? (we've all used it a hundred times)
It derives from an older phrase. "Dropping out of the clear blue sky" The meanings are simmilar.
Lightning, the voltage is so great off the top of a cumulonimbus cloud (thunder cloud) lightning can travel 20 plus miles and strike ahead of the storm while the sky is still clear and blue.
Thus, the saying "out of the clear blue" or "out of the blue"
Every now and then you hear of someone getting struck and killed by lightning with a clear blue sky.
Read more: http://wiki.answers.com/Q/What_is_the_Origin_of_the_phrase_out_of_the_blue#ixzz23BB5V6Ik
It means, "Out of nowhere," or to pose it in modern venacular, "It is an inuitive thought."
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