That's Doc Radawski, and if I may deign to speak on his behalf, he says that as a general range....the island is a big place.
Doc R is on the South side at CCV, and at this general time frame, you can easily expect 82 degrees in the shallows of that area. On the North and West, it often runs maybe two degrees cooler.
In that last week (2/10 timeframe) there were some ongoing rains, the West and North were fairly well shut down with wind and wave. CCV continued dive operations, but you could see that although it was still pretty flat calm on the South, the water was stirred up. Fresh water runoff from rain will do that, but it also throws a layer of cooler water onto the surface. Thus can result in a 79 degree reading, which doesn't sound like much of a 3 degree difference, but it's a shock ascending from the depths at 80-82 and climbing tgrough the 78-79 degree layer.
I have seen water temps in the high 90's in the shallows of the CCV Front Yard, not all that uncommon March > September. Even at those times, if you go to 150fsw, you can find 78 degree readings. The only reason to do that in this otherwise spectacular shallow environment is to go looking for sharks. Not worth it to me, but if you want to- they do like cooler water.
Another consideration is if you're at CCV and doing those 5X a day dives, your core temp is affected considerably more than if you were doing a one or three a day schedule elsewhere. Something to consider in regards to thermal protection choices...an answer of thickness of suit that only you can decide with experience. What I use likely wont work for you, such advice is absolutely anecdotal in the strictest definition.
Looking at the CCV webcam this morning, it was bright and Sunny, seas were calm, again- looking South.