Track time is always good, you just need to adjust your riding to the track conditions. I treat cold days like rainy days - gotta be SMOOTH on the brakes and easy on picking up the throttle, focus on body position, and dial it down a notch or two. There's a lot you can learn on cold and rainy days while riding at say %60 of your normal pace.
Summit Main is slick when it's cold in my experience. If you haven't had much experience with pushing the front through a turn, then be on the ready for it! Tire warmers won't do much on a day when it's that chilly out. If you use warmers, that's fine, but don't let them give you false confidence. You'll lose whatever heat the warmers put in the tires while you're gridding up for your session. If you have those wheel blankets/curtains to shield your wheels from the cold, that helps a LITTLE, but your cold wheels will sap some of the heat out of the tires that the warmers put in them as well.
Keep your body warm. UnderArmour cold gear stuff is awesome, and get a box of rubber gloves (I like those blue ones) - wear them under your gloves and they'll keep your hand much warmer. Good warm socks, and a neck warmer. Be prepared for your face shield to fog up from time to time. If you don't have one of those nose covers on the chin bar of your helmet, some duct tape over the bridge of your nose connected to the chin bar does a pretty good job of keeping your breath from blowing up across the face shield. Breathe Right (or similar) nasal strips are also a must for me on cold/rainy days. Taking some of these variables out of the equation helps to keep your focus on your riding. It sucks when your fingers get numb from the cold and you start worrying about your digits rather than being smooth and consistent on the bike.
But yeah man, go ride. Track time is track time. And if it's your first day out this season, it's a good way to brush off the cobwebs, and it'll force you to take it easy and focus on the most important aspects of riding.
