I am thinking about visiting Miami Beach in December. I have heard that day time temperature averages around 75 degrees in December. But I have been unable to find the average water temperature at the beach. What I need to know is the water warm enough to swim comfortably in December?

First of all, be prepared that it is just as likely to be daytime averages in the 60's (or the 80's) to make that average.

The water is way too cold for Floridian to swim. But it is often "just right" for northerners who come down. If you've ever been swimming in a Michigan or Wisconsin Lake in the summer, you'll probably think the ocean is warm in December!

We've been on the beach in Miami in December--in our sweaters. Brrr! It was just us and a lot of lonely seagulls. Not another single soul in sight.

It could get cold, but usually DEC. still very warm. Water could be cold, but if sun is out, it feels great...

It is basically the Gulf Stream so the water temps don't really dip below 75 degrees.

For what it is worth, the Atlantic Coast above North Carolina 75 degrees is a summer high water temp up through New York/New Jersey.