When I went annually, I always went anywhere from November - February. And the weather could be WILDLY unpredictable, and vary WILDLY during my week (give or take) visit. I've been there in January when it's been in the 70's during the day, and downright chilly (even for a Northerner) at night ( I LOVED it!!). And I've been there when it's been in the 90's during the day. And I've also been there when it's not been hot temperature-wise, but been so daggone HUMID that I was MISERABLE, and my glasses and camera got/stayed fogged up, and I was dripping, irritable, and in pain.
But I still consider the gamble of this time of year MUCH easier to take, and even assume, to some extent, than to make/take during the times outside of my "window months", at least in my particular case. Would not, could not, will not do it. Sam I am.