I'm assuming this didn't show up until after the cold temps. If so, then yep, that's what it looks like to me!
Perhaps others might know different, but since the rest of the plant looks healthy and green, I see no reason to suspect otherwise.
Barb

This is exactly what mine look like in Houston after that 28 degree with frost night a couple weeks ago. The yellow leaves will drop, and you will get new beautiful growth in the spring and recover nicely.

See my post under Hibiscus Indoors--do I have the same problem?

Thanks!

These pics are of tropical Hibs, correct?

Can't anyone answer this question?

Yes, they look like tropical hibiscus.

Thanks!