Hi Tinkermom3
We cruised at the end of February last year (2/26 - 4 night).
There was a cool wind, but it was sunny at Port Canaveral when we left PC. The first night the sea was VERY rough and I was having serious concerns about the rest of the trip.

However, I have since learned that it is common for the first night to be rough / choppy seas due to the currents the ship is crossing.
However by the time we woke up, docked in Nassau it was a beautiful day
Temperatures were really warm, without being overly hot, just right IMO ...and so it remained so for the rest of the trip.
We had no problems docking at CC and we had a lovely day there. We swam in the sea and lazed on the beach

Our day at sea was equally good calm, warm & sunny .....nice enough to catch the rays on the deck.
Even back at PC the weather remained good.
Yes, I believe the weather can be variable, and I do also think that people opinion of water temperature / hot weather will also vary depending on their own comfort levels and what they are used to at home/holidays.
Still, plenty of people are repeat cruisers in December and January, let alone February, and Disney ships sail full even then..... so on the whole, while you can be unlucky, I don't think it can be all that bad
Hope that puts your mind at rest a little, and hoping that 'lightning doesn't strike twice' for you
