Mr. Amber Cat always did something like this, every Spring. And his idea of Spring was anytime between Jan 1 and May 15. It would start for no apparent reason, and eventually go away, and I would suddenly realize he'd been quiet for two whole days!

Also, if it is a full moon, that brings out the weird in some cats (I'm not sure what phase the moon is in tonight.)

So, as someone else said, if all else is well, he is just being a cat.