With such a large gap weather wise it will be hard to determine what to wear until closer to race time. I kind of like winter running and as long as the wind chill is not below 0 I run outside even in winter, I just can not stand the treadmill. Even on training runs anything above 40 is shorts weather and a short sleeve shirt for me. A half that is above 40 will have me take my shirt off after about 5. I am pretty good at getting up to temperature and not wearing a shirt makes me feel a lot cooler. 30's is usually a long sleeve running shirt (something wicking) and wind pants. I have a hind and brooks jacket and a brooks wind shell for if it gets colder and I may start in a running hat or band that covers the ears if it is cold. It really depends on how far and fast I am going and also if it is the beginning or end of winter. What seems cold in November doesn't seem so bad in February. Specific brands are hard because what works for me might not work for you, plus a lot of brands have different fits for men and women. I would recommend going to a local running store to see what they have. Most of my wicking shirts are shirts I have gotten at races, so they are all brands.
Of course everyone is different so just because all that works for me doesn't mean it will work for you. Here are a couple of guidelines for longer races in cold weather.
First and most important...avoid cotton. It just absorbs sweat and you will end up wet and cold. This includes socks.
You want to be a little cold at the start, you will warm up after a couple of miles.
If you don't want to shed a layer and lose it or get stuck carrying it around with you wearing a garbage bag is a low cost, low tech, and very efficient way to start a race or wait in the corral. Just cut a head out for the head and wear it until the race starts. They are keep the warmth in while you are just standing and you will feel a refreshing burst of cool air on our running body when you shed it. Some people shed it right at the start and some after about a mile so they build up some warmth.
Something none clothing related also to keep in mind is to stretch and do some short warm up jogging to get the muscles loose. It is a lot easier to pull a muscle if they are cold, I have had to learn this lesson the hard way.
Good luck and congratulations on your first half. I'm curious, which half are you doing?