The sun causes you to perspire, which removes the water from your body but leaves the alcohol in. This can cause impairment to happen more quickly. A blood alcohol of .10 or more was found in 30 percent of the fatalities. Only time will sober a person, NOT black coffee or a cold shower. It is NOT easy to tell if someone is impaired.
Many experienced drinkers can hide their impairment.
You are NOT the best person to judge if you are fit to drive. Your judgement is one of the first things you lose when you drink. Remember, safe boating starts before your first trip out on the water. Do not wait until an accident happens to educate yourself as well as your family on the rules of safe boating. DON'T mix alcohol and boating.