Jesus answered and said unto them, "When it is evening, ye say, It will be fair weather: for the sky is red. And in the morning, It will be foul weather to day: for the sky is red and lowering. O ye hypocrites, ye can discern the face of the sky; but can ye not discern the signs of the times?" "A wicked and adulterous generation seeks after a sign; and there shall no sign be given unto it, but the sign of the prophet Jonas." And he left them, and departed. Matthew 16:2-4 (KJV)