It's funny living on a steep hill like I do. I swear that during these transitional periods between seasons, with warm days and cold nights, the cooler air basically just slides through my yard and settles lower, and this, in turn, displaces some warm air that moderates the temps up on the hill. I can't come up with a better hypothesis as to why it happens, but it does. I'm never comfortable with the forecast being below freezing and not doing anything, so I'll probably be throwing a lot of bed sheets onto my trees this weekend and hopefully (?????) won't need it.