You should tell the priest. Never go to the woman directly.
What? lol
Like the priest has time for that at the moment of stopping her (or him) from entering. You need ushers for that.
For regular church "members" this is an easy, "fix it or leave" scenario, if they are out of town and probably think it's a regular Novus Ordo Church, well, they're in the wrong place if they can't change. Sorry. This is a bigger offense to God than people think, in my opinion.