Nova Scotia to Baja California

Thom and jplante have excellent advice. I have used all of those routes in the winter. The best advice is get south as fast as you can and avoid Boston, New York City, Baltimore and Washington DC. The suggested routes by these two people do that. I prefer I-20 over I-10 as it is shorter and has less traffic..... however it is further north than I-10. If the weather is good use I-20 as the two roads become one in West Texas.