Issued 331 PM EDT Sat Oct 20 2018 Valid Sun Oct 21 2018 - Tue Oct 23 2018 ...Heavy rainfall threat the lower Texas coast and Rio Grande Valley... ...Much colder air across the Midwest and eastern U.S.... A slow-moving frontal boundary extending from the southern Mid-Atlantic region to the Gulf coast region will continue to provide the focus for showers and thunderstorms as it pushes slowly southeast this evening. As the front begins to move onshore and high pressure settles i...