Yes!
The scion exchanges promote January and February but that's out of convenience for when we prune just before flowering and when we prune other trees. The best times to graft are usually late spring but you can graft avocados really any time of year because they are Evergreen and are growing throughout the year. You can graph now and so long as your root stock is still pushing New Growth had a good clip it will grow well. Just make sure you protect from the Heat and the sun. Let The graft push two or three flushes and then it should be set. I have seen graphs push one flush and then die afterwards. I don't know if this is because there is eventual graph die back or if the graft is weak and becomes easily dislodged by critters.