Yes, you read that correctly!
It might be slightly nippy but that’s no reason at all to hang up the ol’ diving suit and wait for summer.
Do as I do and get yourself a Waterproof D9 breathable (http://waterproof.eu/en/products/drysuits/d9-breathable/) and the Waterproof Dry Glove set (http://waterproof.eu/en/products/accessories/drysuit-accessories/ultima/) and the cold will not be a problem anymore.
I’ve gone diving almost every week in November and December (and the previous months but the temperatures really started dropping in November) and I haven’t had any problems.
In 30m depth, it’s cold anyway, so why not make the best of it.