Two tropical depressions gained strength off the coasts of Mexico and became tropical storms Sunday − and one could become a "significant hurricane" by Wednesday, the National Hurricane Center warned.

Chantal has weakened into a post-tropical cyclone and the flash flood threat from the storm has wanted, according to the National Hurricane Center.

The Atlantic coast of the United States is set to experience an active and dynamic hurricane season in a possible repeat of last year’s lineup of devastating storm systems, experts warn. As many as 18 ...