From the Richmond Daily Dispatch February 5, 1863:
The coldest night.
–Tuesday night was the coldest one since 1857. This fact was ascertained by a comparison of the thermometer at the City Water Works, where the mercury in the tube indicated eight degrees below zero. Should the present weather continue, our soldiers in the field must suffer considerably. The signs of the times indicate that we shall be afforded more opportunities than we care to embrace for getting in a supply of ice sufficient to last through the summer months.
You can read about the Ice trade at Wikipedia and Ice Harvesting at Historic Sodus Point.