Map: Track Cristobal as the storm makes its way to the U.S.

Here comes Cristobal.

The rain-heavy tropical storm, which has already brought flooding to Mexico and portions of Central America, is forecast to gain strength as it travels across the Gulf of Mexico over the next 48 hours.

Tropical storm-force winds could arrive in the U.S. as early as Sunday, according to the National Hurricane Center at NOAA. Parts of the Florida, Louisiana and Mississippi coasts are under a Storm Surge Watch.

Track the movement of the storm center and the latest in the forecast from the National Hurricane Center with this map:

source: nbcnews.com