Rochester has a problem with flooding but it's usually in the spring and usually minor flooding. The Zumbro River flows thru the city and the flooding is usually along the river with the occassional bridge being closed. The majority of the flooding that you've been hearing about on the news is an area that is about 50 miles or so directly east of Rochester. The reason that it's so bad is because that area is very hilly and the majority of homes are in the valley so all the water is running down into the towns. It is very unusual for the area to get that much rain but it does happen. The annual precipitation for MN is around 24" for the entire year. Some of these towns got about 10-15" in a day or 2.
As for computer jobs, I know there is a company whose headquarters are in Upstate NY (poughkeepsie I think) that has a branch there but I think at the moment they are either having problems finding people to do the work or enough work for the people who relocated there from NY.
Rochester is close enough to The Cities to go to sports events, concerts and theatre.
There seems to be a varied mix of people from all over that live there and of course there are the usual conflicts when cultures are combined. I think the main misunderstanding or problem has been between some Somalian immigrants and the locals. Not sure about this though.
I think that the largest employer in town is the Mayo Clinic. I'm not sure about the job market in general down there.
As for schools, Rochester has a community and technical college. You can check out
Minnesota State Colleges & Universities for locations of more state colleges and universities in the area.