Would you go in? I'll dip my toes in Lake Ontario but I'm not swimming in it.
You really can't swim in that temp for very long....It just drains your strength in a quick few minutes. I tried it once and then understood how people drowned so easily.
From the web....
Cold water can kill you in less than a minute. It's actually so dangerous that it kills a lot of people within seconds. Thousands of people have drowned after falling into cold water and a
lot of them died before they even had a chance to reach the surface.
That's a scientific and medical fact that most people have trouble understanding - because they have no personal experience actually being in cold water. When they hear or think about 50F (10C) water, it doesn't sound particularly cold - or dangerous - because they're
mentally comparing it to 50F (10C) air. It's a big mistake that gets a lot of people killed each year. This is explained in much greater detail in the section
Why Cold Water is Dangerous.
You should treat any water temperature below 70F with caution.
coldwatersafety.org
.
Water Temperature Safety Guide
Below 77F (25C)
Breathing begins to be affected.
This is why the official water temperature required for Olympic swimming competition is 77-82F (25-28C).