A tropical storm warning is in effect for parts of Texas as Tropical Storm Don approaches the southwestern U.S. state, bringing with it much-needed rain.

Storm warnings have been posted from the mouth of the Rio Grande to Matagorda as the weather system swirls in the Gulf of Mexico, moving toward the west-northwest. The National Hurricane Center in Miami said in its latest report that Don is currently 155 kilometers southeast of Corpus Christi, with 85 kilometer-per-hour winds.

The center of the storm is expected to strengthen before coming ashore late Friday and move across the southern part of the state Saturday. Steady weakening is expected after Don makes landfall.

Normally, U.S. officials worry about the vast damage that can be caused by tropical storms, and more powerful hurricanes with winds of 120 kilometers an hour or more.

But this time, Texas officials say they are looking for Don to produce much-needed rain. Forecasters expect the system could produce up to 15 centimeters of rain in some areas. That could alleviate water rationing regulations, and provide water for parched lawns and drought-rutted farmlands. The officials say they do not expect to have to order residents near the Gulf of Mexico shoreline to evacuate.

Texas has had months of drought and parts of the state have an annual rain shortage of about 38 centimeters.