Flooded on Vacation

My parents are out of town in Minocqua Wisconsin with some friends for Memorial day weekend. My sister and her boyfriend went up as well on Friday and are also spending the weekend up there. Grandma went up to Aunt Laurel and Uncle Larry's lake house for the weekend so she is gone as well.
I couldnt request off work this weekend because it was opening weekend for hangover and I have class on Saturday mornings anyways so I had to stay home. I'm not complaining though because its been great having the house to myself for a while. Today the entire basement flooded though. I went down there earlier to check on everything during the storm and sure enough we had water. I get down there and theres a huge puddle coming out of the water softener closet. The next closet over which holds all our camping gear and boxes of random stuff is full of water also. The basement bathroom also flooded and I have no idea how. There is water everywhere downstairs! On top of all the flooding mess in the basement our cat wont come back. The cats hadn't been outside all night so they were really wild and crazy this morning running around the house. They had so much energy so I let them outside early this morning. It was just cloudy then but later on the storm came through and I was calling them for ever. Harry eventually came running inside but its about an hour later and George still hasn't come inside. Is he just hiding or maybe something happened to him? I'm kind of freaking out about it right now but I'm trying to think positive that he'll come back later and I'm trying to worry about the basement issue. I've talked to my parents multiple times, laying towels out isn't doing anything and I cant even mop it all up. John suggested using the shop vac that we have in our garage. I don't even know what a shop vac is let alone how to go about using it.
HELP!!!!!!!!!!!!!!!

Aunt Laurel and Uncle Larry are supposed to be around sometime this afternoon dropping grandma off so I'm hoping they can help me. My dad said I'm just going to have to leave it until they get home on Monday otherwise. Theres not really anything else I can do. I hope we don't get anymore water down there. I also hope George comes back because I have work later. Theres no way I can leave for work knowing George is still outside in this weather.