Know what each member has for gear within the group and what their skills are before leaving the beach. The discussion of contingency plans should be a consultative endeavour, and done at before launching. A VHF radio or cell phone is a worthwhile investment, regardless of the time of year. As most winter paddling is not too remote, direct line of communication and range receptivity is usually not a problem. Excellent waterproof protection is available for these devices, allowing them to be used while kayaking.
Small charts are available for many prime kayaking areas.
They fit on your deck nicely, giving information that may help you avoid marine hazards. You may also want to perform the supreme test of preparedness by practicing self and assisted rescues in actual cold, rough water. This can be done under controlled conditions with highly experienced paddlers at hand or with the accompaniment of a chase boat. Part of the reason time is taken to plan and exercise good judgement in choosing your winter routes is to avoid potential risk and inconvenience. Marine hazards only impose themselves when you are ignorant of them and fail to plan ahead or adjust.