Florida Keys in December

[emoreira]

3/2 is fine for me in anything above 68 or so. You'll be fine. Weather is a bit unpredictable that time of year though.

I'm just in the Miami International Airport waiting my fly back to my country. I've arrived last Saturday morning for a Telecom Conference starting on Monday. I had reserved a place for a dive trip on Sunday morning.
All diving activities were suspended this week owing to hurricane IDA. Strong winds and high seas.
You cannot imagine how upset I was. I've been waiting this trip and the diving reward for months. Nothing could be done. No one is to blame, please, do not misunderstand me, but it was a real pitty.

[suzette]

There are a lot of great Ops in the Keys. Many however don't do snorkeling. Rainbow Reef does do snorkeling, but I *think* they put snorkelers on one boat, and divers are on another. Since you plan to dive one day, and snorkel on another, I'd say none of that is a problem.

If you are MM100, and diving the upper keys, I would recommend N. Dry Rocks and NN Dry Rocks for both a dive, and some snorkeling. The water is very shallow, but it's generally not a crowded spot.

Snappers Ledge is another cool spot with a ton of life.

The City of Washington is a cool spot as you can do a bit of reef, and a bit of wreck. They also feed the fish out there, and there are generally some Goliath Groupers about, as well as Nurse sharks, and the regular cast of characters.

Have fun, and enjoy.

I agree with everything here, except one thing- Rainbow will put the snorkelers on the same boat as the divers- if there are snorkelers on, the captain will pick a site that's both diver and snorkel friendly, like snapper ledge, the Benwood or the like.
In the interest of full disclosure, I do not work for them, but my husband does and I dive with them several times a week (on a good week!) They also put a guide in the water for each dive at no extra charge, so they are (IMHO) a good choice for someone without much navigation experience.

[Garrobo]

emoreira: I know how frustrating the weather can be. It's usually pretty mild around Key Largo and Islamorada where I do most of my diving. Yet, some days, it gets a little rough and the dive operator who I use is pretty conservative and will cancel on their own if they think the waves are too high. Also, on occasion some of the divers will cancel if they are afraid to go out for one reason or the other in higher seas. Then it isn't economical to just take out one diver in an eleven ton boat with twin diesels. That's when I get on the telephone and bring up other dive shops or the operator starts calling local people, offering them a break on the fees so as to get more people on the boat. In four years of going to the Upper Keys I got stuck in the motel for a day only one time. On several occasions when my usual OP wouldn't go out when we got out to the dive sight with another OP there was only an 18" chop. I see no problem with having a mix of snorkelers and divers. I've dived many times with this combination. They are up top and can get back on the boat at any time or just float around till the divers are back on board and they do not interfere with the divers down below. I go to a weather website which has a 10 day forcast for about everywhere in the USA. Also, you can get local Keys wind/wave forcasts on the NOAH's website or the Weather Channel.If I knew how to include a link I'd post them here. Maybe someone else a little smarter can do it. Better luck next time. S*** happens.

[Steveginthekeys]

If you dive Largo you will not even feel like you have been to the keys. Go at least to Marathon (I recommend Captain Hooks and ask for Hilary), lots of shallow water diving and snorkeling, great places to eat and not as crazy as Key West (yet only 50 miles away). A thin wetsuit or even a shorty will work fine for most people...I have never been cold in the water in the Keys in December and I have a hundred dives at least in December alone. A dry suit...you must be kidding.