Is it possible for my husband to take my name off our joint bank account without me knowing or telling me about it?
I would call the bank ASAP and ask them.
The bank shouldn't have let him do that unless he has a power of attorney. As for the question of is it OK, that depends. Personally I'd be really upset with both him and the bank but I'd ask him why he did it. If it's a good reason fine, I'll get over it, but if it's a bad reason I'd blow up at him
When I closed an account with my ex, we both had to appear with photo ID to do so. If not, the not present party would have to sign and have documents notarized.
It should not be possible for them to do this. When my husband and I closed an account we had, we both had to be present at the bank to do it. I would call the bank, though, asap, and see what the story is.