Wind-Chill-Factor

Actual air temperature is not the whole story: when you are outside sailing the airflow around you will remove heat from your body, and therefore the perceived temperature will be lower than the actual one. The result is that you will feel much colder when there is a wind blowing.

This must be taken into account when deciding the length of time that your crew will spend on deck on watch. Keep the hot drinks flowing and look for early signs of Hypothermia.

Wind-Chill-Factor

	Temperature (C)
Wind knots	>	15	12	10	5	1	-5	-10
	5	13	10	8	2	-2	-8	-13
	10	10	6	4	-2	-7	-15	-21
	15	8	4	1	-5	-11	-19	-26
	20	6	2	-1	-8	-13	-22	-29
	25	5	1	-2	-9	-15	-24	-32
	30	5	0	-3	-10	-17	-26	-33
	35	4	-1	-3	-11	-18	-27	-36
	40	4	-2	-4	-12	-19	-28	-37

Source: UKSA