How was the weather like the night the titanic sunk?

Crystal clear and very calm, but freezing cold with sub-zero temperatures. The sea was 'as smooth as glass' according to survivors, with no wind or waves. There was no moon but the sky was ablaze with stars, and it was EXTREMELY cold- water temperature was at least -17 degrees Centigrade, meaning that nobody could survive for long in the sea.

Daybreak saw the seas getting a bit rougher, with a heavier swell on the sea and a cutting North-Westerly wind. Fortunately though, the survivors in the lifeboats were rescued by the SS Carpathia soon afterwards.