I was on Trulia checking into a property for a buyer client and happened upon your question about our weather. I don't feel that the earlier answer was correct. While we may have a 30 degree day here or there in the winter, there are typically stretches in January when the temp may not even reach 0 degrees. So to say that our winters are in the 30s is quite misleading. Also, we do see our share of warm, summer temps, but our "summer" is short-- about 8-10 weeks!
Our temps change rather dramatically, too. Today for instance it's 32 degrees outside. Last week it was 55. One just never knows.
From November to the end of March or early April we'll see a decline from the 30s down as low as 0 or below, then slowly back up to about freezing by early spring.
Spring weather comes about mid-April while summer weather starts about July 1, lasting until about mid- September. During that period the days are warm (70-80ish) and the night temps dip into the low 60s. Once in a while we have temps in the 90s, but it's unusual.
Our weather isn't as severe as Chicago's, Minneapolis', etc., and it certainly is gorgeous here no matter what the thermometer says. Feel free to contact me if you'd like more information. email@example.com