I have only ever lived in 3 places in my life: Chicago, New York and Montana, so I am familiar with long, brutal winters. Sometimes it seems like winter will never end.
In the midst of my first Montana winter, a friend of mine joked, "Last year, summer in Montana was on a Tuesday." He was lucky that he was talking to the only person in the world who could possibly find that funny. I love winter, though. The crisp air has always cleared my mind in a way hot, humid weather never could.
But it is undeniable that winter makes running harder than in warmer months. You can't just throw on some shorts and a pair of shoes and head out the door. Winter running takes a bit more preparation but cold weather is no reason to stop running.
When attempting to run in the cold, each runner should first be sure to spend time warming up properly. Doing dynamic stretches and starting each run slowly will help allow your legs to warm up and prevent injury. Cold weather runners must also take time to consider the proper gear for the conditions.
If it is cold but there is no snow or ice then this consideration is made simpler. Any good pair of running shoes will work in cold weather, though if it is very cold you may want to throw on some thick wool socks. The nice thing about wool, in addition to the warmth it provides, is that it is a naturally moisture wicking material that prevents blistering very well. There are also several brands that make merino wool t-shirts, leg-tights and outerwear for runners. So, if you love your wool socks, you might like a merino wool t-shirt as well!
Regardless of material, you will want to make sure that both your upper body and lower body are warm, but you can decide what clothes you prefer while running. Also, make sure not to forget a hat and gloves, because a cold run can be made unbearable without those basics.
One final piece of apparel to consider is a buff. I used one every run this winter whether it was 30 degrees or -30... If you have never used one, a buff is basically a circular piece of cloth that can be worn around your neck for warmth. If it is super cold, you can also pull it up over your mouth to create warm air while breathing through it. On less cold days, the buff can serve as a headband when it is too warm to wear a hat, but too cold to have nothing covering your ears. Basically, a buff is an all-purpose piece of apparel that anyone who runs in cold weather should utilize.
If you live in a snowy or icy region, gearing up for winter runs can be even more complicated. Slipping and falling on ice while running can happen easily, leaving you upset and possibly injured. There are several gear options that help prevent slipping when conditions are icy. First, you could purchase traction devices that go on your shoes. My personal favorites are Kathoola Nano Spikes because they are super small and non-intrusive, yet they do a great job of preventing you from falling.
Another great option would be to get a pair of running shoes made with non-slip rubber. Many of the major running shoe companies put out a shoe each year that is designed specifically to prevent slipping. The final option would be to avoid running outside entirely by running on a treadmill.
Winter should never stop you from running. As long as you dress properly and start your runs slowly to allow your legs to warm up, winter will never be a hindrance to training. So, while everyone else is stuck inside, get out the door and go enjoy nature which you will likely have all to yourself!