Wind certainly is a big factor. Many wonder why ice doesn't form right away when it hits 0 degrees (C). It is all chemistry and thermal energy. Once the water reaches 0 degrees (C) it takes a very large loss of energy in order for the molecules of water to change to a solid. This is known as Heat of Fusion. For example it takes the loss of 1 calorie to drop the temperature of 1 gram of water 1 degree (C). This is true until water reaches 0 degrees(C). Water must now change from a liquid to solid and this takes an additional loss of nearly 80 calories per gram of water. If you placed a thermometer in the water and watched as it cooled you would see a steady decline in temperature until it reached 0 degrees (C) then the temperature would remain at 0 degrees until all of the liquid had changed to a solid (ice).
If you have trouble understanding this don't worry my chemistry students had trouble also!
