MIAMI (AP) - A day after forming, Tropical Storm Don is moving across the Gulf of Mexico toward southeastern Texas, where it's expected to make landfall Friday.

A tropical storm watch is in effect from the mouth of the Rio Grande northward to west of San Luis Pass.

The National Hurricane Center in Miami says Don's maximum sustained winds Thursday are near 40 mph (65 kph) with some strengthening possible.

The storm is centered about 545 miles (875 kilometers) east-southeast of Corpus Christi, Texas, and is moving west-northwest near 10 mph (17 kph).

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