Gosh, carrotop, you heard spring peepers in January? Wow!
Robins show up here in large flocks in late winter. I have not yet seen them. Last year while I was out walking I saw a huge flock of robins in two silver maple trees. There were so many that I stopped to count them (roughly) -- there were over 150 birds.
We have cold weather right now, very wintery. Sometimes we get a little January thaw like you had.
I am really looking forward to spring.