Interesting. I've never seen so much water near Black Mountain, but I haven't been going there in nasty conditions since the gate is almost always locked if the trail is wet. The Cleveland NF site still shows Black Mt., Upper Santa Ysabel, and Lusardi Truck trail as closed. I assume the gates were open when you got there.
I figured the gates are closed at the slightest chance of nasty weather by the very close-by Ramona ranger station. Maybe they left Friday night and didn't have ranger coverage to lock 'em Sunday?
If
http://www.fs.fed.us/r5/cleveland/conditions/ says the trail is closed but you found it open, it wouldn't be the first time I've called Cleveland HQ to advise them the web site is not being kept up to date. Sigh......