That is what a normal mix of fescue and Kentucky bluegrass looks like in the colder climates this time of year. Does it green up in the summer? If so then that is what you have. The lawns which do not look brownish in the winter are 100% fescue lawns.

Kentucky bluegrass normally goes dormant when the weather cools down. It does not have to as was proved on another forum, but to make it so that it does not turn brown is a Herculean effort. Do you want to take that on? It involves getting a good soil test (not a university or extension service test) and then getting good advice as to how to proceed with those test results. And then it further involves frequent organic fertilizer apps all season long. Here is a picture of what that looks like...

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This lawn is in Eastern Pennsylvania. It is 100% Kentucky bluegrass, as are the rest of the lawns down the street. In the summer his lawn looks even better. That picture was taken in April, 2010. Owner is morpheuspa if you want to look him up.

Thanks so much for the information. I'm sure you are spot on. If I think of it, I'll post a picture in a month or so of the same area, so others can compare it to their own situation.