What is the tick bite danger season?

April-September. During spring and summer ... When we [and the ticks] are enjoying the gorgeous weather.
Agree with Dr. Yep. But i would also add that ticks can become active if there is any period, a few days or longer, with temperatures exceeding 55degrees. So, if you have a warm week in december, it's possible to get a tick bite then (although not terribly likely).