I’m training for my first HM on 10/10 (Nantucket!) then I’ll take a few weeks off and start training again in early Nov. Also I live in New England so any tips for training in the bitter cold, I’m all ears. (I’m so afraid I’ll end up on a treadmill for the last 6 weeks and that can’t be good right?)
Clothing layers are your friends. I run throughout the winter except for when there's too much ice on the roads. You will need to experiment to find what winter gear works for you. I can run in a long sleeve shirt, tights and a wind-resistant headband, running gloves for many temp conditions--down to about 30, I'd say, because I get warm when I run. But if it's colder, windier, snowier, etc, I also have a heavy wind-resistant running shirt, some warmer underwear, smartwool socks, wind-resistant hat, running mittens So I just adjust to the conditions.
I bought a pair of running cleats for when it's snowy/slight;y icy underfoot. IMO, they seem to work best in packed snow conditions. If it's icy outside, I just don't run outdoors.
Treadmills can be your friend. Use them when your need. They can keep you on track with your workouts when the outdoors just won't cooperate. I have done a 15 mile run on a treadmill, and while it required some creativity to keep it from being too boring, it kept me on track (my secret was to break it into 5 mile segments and switch treadmills. I was at a gym, so that worked for me)
You'll find a way to make it work.