Cat-4 and still strengthening. Sustained winds of 140 MPH in the core.
Sounds a bit like Camille. Camille was a cat 5 and struck on the other side of Louisiana, but it weakened, swung up to Ohio and out to see where it reintensified into a tropical storm.
Calcasieu has a recently-closed refinery. Port Arthur has the biggest single refinery in the country (Motiva).
In Harvey, you had so much rain it collapsed the roofs of oil tanks. I don't think this will be a similar rain event from what I've seen (it's projected to move, not linger). With this storm surge, you hope that the berms around the facilities aren't overtopped.