They foiled the head and shoulders topping pattern which is usually bullish, but I have a feeling it will be a whipsaw kind of day. Futures should find resistance at around 4k in the morning session and then another test of 3900 next week to take out stops (yellow arrow). A bigger sell off would likely get us back down to 3800 by Thanksgiving (red arrow). I don't think the rally today will continue past the previous high of 4050 - as of now.
Good luck!