The 'ol drinkin' buddies are a common topic here. And for good reason. Many of us have had to face it.
You've received some excellent feedback here. I wasn't entirely sure when you said "entertain him" whether that meant he will be staying at your home (if so, it sounds like he invited himself) or that he'll be at your place but not for the whole visit.
I can only add that in addition to having a dry house, whether he's with you for all or part of the time, you need to be upfront with him. A thoughtful email can help a lot.
I'd lay it on the line honestly. Something like this:
"Both before and after my recent accident, I've had to ask some hard questions about myself and my drinking. As part of that process, I am no longer drinking. It has made me feel better about myself, my business and my marriage to your sister, who is the world to me.
"I want to let you know in advance that there will not be alcohol in our home. It's the right thing for me -- and your sister. I also wanted to do the right thing by you and let you know about this in advance.
"I'm really at peace with my decision and thank you in advance for supporting me. It's going to be really great to see you here in Minnesota."
How's that work for you?