I don't know what part of NY you are coming from, but with a trip like that (NY to NC) I'd break it up. I live near Buffalo. I've been going to So. Pines from here which is about 938 miles one way. I have one horse and a 3 horse GN which is opened up so Harry can ride facing backwards because that's the way he likes it. He has plenty of room to move, and plenty of hay in front of him.
You never can be certain of roads and or weather or traffic problems. I've always stopped half way with friends so that I got there during the day and was able to turn him out for a while before supper so he could stretch his legs.
Last year I went to SE VA. I still stopped half way. I tried for almost 2 weeks to leave but the weather and roads were so bad I did not want to take a chance. I finally left the first day the roads looked decent. It took me 45 minutes to drive 13 miles to get to the main highway.
Through the mts. on 15, they had closed the Southbound 2 lane, and just had the Northbound running South and North from the top of the mt at Fry Bros Turkey Ranch to just north of Williamsport. (The roads were so bad the day before they had semi's in a pile at Lawrenceville because the roads were so icy getting up on to the 4 lane. By the time we got to Fry Bros, the roads were one lane and okay, but then we had one lane S. one N. and a Jersey barrier for about 18 miles. There was just enough snow on either side of the one lane to 'hold' the trailer in a groove. It was fine by the time we got to Williamsport, but because of the backups and road problems we were 3 hours later than scheduled. I was exhausted, and glad we stopped moving, as I know Harry and Tutti were as well.
I was an owner operator truckdriver for 15 years and drove FL to Boston every week, and through the Winter to Idaho, Oregon, and AZ. I know how stressful driving in the Winter can be, and how unpredictable the roads, weather and traffic can be. No need to put your horses through this especially since they have limited movement in a 2 horse. Can you do it? Sure, but consider the horses - and consider yourself. They need to be able to stop moving and relax, drink and eat, so should you. Not all horses will drink in a trailer, or eat. Some of them never poop or pee.
This can cause a variety of serious problems.
If it's below 30 degrees, I'll put a sweat sheet on Harry, crack the windows in the center, and put a thin wool sheet on until the temps get above 45 (usually around Williamsport). I stop, pull off the wool sheet and leave the sweat sheet. He is a travelling man, and doesn't get sweaty. The next day he goes naked because it's been (for the last 5 years anyway) in the mid 40's.
We stop every 100-150 miles for about 15 min. Long enough for me to get fuel and a coffee and take Tutti for a walk and get some fresh air. With the exception of last December...we've managed to arrive fresh safe and happy.