Yes, snake boots would be a neccesity here. I have only lived here ( south west GA) for about 14 months and have seen 12-13 rattle snakes, 2-3 moaccasins and countless non venomous species. Even in winter months the temp doesn't drop below 60's in the day. Probably 5 out of 12- 13 rattlers were seen in Oct - Dec range. Though they were not really responsive they were out of the ground. We actually have a festival here in Jan. called the "Rattle Snake round up" I hope this was of some help to you.
Absolutely needed and necessary.
As waltor stated it doesn't get cold enough for them to completely stop moving about. Those Cottonmouths can be really aggressive and will come looking for trouble.
If you will be wading thru water or easing along swamp edges I would go a step farther and get some snake proof chaps as well and watch your hands, most snake bites are to the hand/forearm area.
Try to put your tree stand in a tree with plenty of background cover, keep the prevailing winds for that time of the year to your face, and take care of those pesky squeaks and creaks your stand may have developed while sitting in the shed. A good treestand lube can be made by heating petroleum jelly until it reaches a liquid form. Some hunters have reported success by including a cover scent in this mixture before applying it to their stands.