When is the best time of year to drive from California to Maryland?

When is the best time of year to drive from California to Maryland?
That depends on where you plan on crossing at. If you are crossing closer to the south then I would cross in the spring when everything is in bloom. I wouldn't cross in the summer because it gets very hot and would be uncomfortable even in an air conditioned car. If you are crossing closer to the north, I would go in the fall so you can see the aspen change color in Colorado. I would not go in the winter because it's very cold there would be a chance of road closures due to snow and ice.