Seriously
Having been dunked and thrown off a boat in a F10 gale in the Mil for sea survival think long and hard about what you wear and take
Essential is an emersion suit with warm clothing underneath
ELT
Life jacket
Liferaft
Most will laugh at this, I can assure you having spent 1 hour off Plymouth in the sea with water temp of 5degrees the sea is an unfunny place to survive.
I do a lot of windsurfing this time of year and wear a 5mm wet suit. Still get cold after a couple of hours. Normal clothing in the Irish Sea probably 30 mins at most before hyperthemia and death.
Choose the shortest distance across, check the weather, very difficult to make out an horizon in grey cloud, grey sea if you cant see the land.
Most of all enjoy it and the last tip, the ac will sound different when you coast out, nothing wrong with it just your hightened senses.