Rideable? YES, use caution and good judgement.
Let lots of air out of your tires and be very careful of down hill or off camber turns in the trees or anywhere you can build up a little speed.
Thin snow over ice is the conditions I would call it. Whole trail is rideable.
If your sliding or spinning let more air out of your tires and please try not to lock up and slide your tires. When you slide you expose the ice beneath making it no fun next time around.
Couple people in there earlier today. By the looks of things they were sliding all over the place due to high tire pressures.
Once I got my pressures right I didn't have to walk a single hill.