abigkahuna
As of 11 PM Thurs. Nite: Tell him to get out. If he can move fast, leave no later than noon Saturday - at the very very latest if he feels lucky. Forecast is sustained winds of 35mph, gusts of 70; buckets of rain. Rain and lightning perhaps tornados, power problems, etc. etc. If the predictions of a stall are right, this could last for days.
That's how it looks at this hour. If it were me and I were vacationing, I'd leave Friday heading West.
Of course things could change, Rita is wobbly right now. I would strongly advise either: He keeps a constant eye on the situation, or you do it for him and call. He and his wife should be prepared to bug-out quick.
Local tv with weather at: KLTV
One foot/two feet/three feet of rain depending on whether it stalls out there.