Since water conducts heat from the body 25 x more efficiently than air, cold water can kill if you're not prepared. Even water temperatures the same as a fairly comfortable air temperature, like 50ºF, can be dangerous. Please do not minimize this danger. People have died when their kayak or boat capsized in cold water, not from drowning, but exposure to the cold.
Cold water means a wetsuit, or, in extreme conditions, a drysuit. Now when do you put on a wetsuit? The simplest answer is, “When you start feeling cold.” But that's not enough. There are all sorts of wetsuits, generally categorized by thickness. The long and the short of it is: the thicker the wetsuit, the warmer the wetsuit. Wetsuit thickness is measured in millimeters.
The O'Neill website has a gauge for how thick your wetsuit should be for a given temperature, which isn't a bad guide. They say at temperatures 5ºC (41ºF) to 10ºC (50ºF), wear a thick 5/4 mm wetsuit. This means a wetsuit with 5 mm thickness at the torso and 4 mm thickness at the limbs. They suggest a 4/3 mm wetsuit when the temperature gets to about 15ºC (59ºF). After that. a thinner wetsuit of 3/2 thickness is fine until the water is warm enough for no wetsuit. (Wetsuits can get even thicker — up to 8 mm — but these aren't used commonly.)
The O'Neill Mutant wetsuit, a serious 5/4 mm wetsuit with a detachable hood. It's warm and cozy.
There are short-sleeve suits and “shorty” wetsuits available too. Shorties are wetsuits that are like a pair of horts and tee shirt attached to each other. Also available are a type of suit called a “Farmer John”, which resembles a farmer's overalls. Farmer John wetsuits can also be nicely combined with a wetsuit jacket.
A Neil Pryde shorty wetsuit.
An NRS Farmer John wetsuit. (NRS is a kayak supply company but they sell great accessories, like wetsuits and booties, which windsurfers can use. They're prices are good too.)
This is a simplistic explanation, of course. You need to experiment what temperature is comfortable for you. Keep in mind that air temperature is an important factor. If the air is 65ºF and the water is 43ºF, make sure you wear a wetsuit for the water temperature, not the air. Even if you're sweating and losing pounds of water weight, wear a wetsuit for the water temperature. One fall will teach you why.
An important thing to remember if you're going out in cold water is to never go out alone during dangerous conditions. If you get in trouble, nobody can help you. Also, when the water is cold, don't go out in wind above your skill level. You'll get tired wrestling your gear and spend a lot of time in the water. Better to wait on shore and ask the more skilled sailors a lot of questions.





















