McALLEN, Texas (AP) — Texas mobilized National Guard troops and residents along the Gulf Coast near the Mexican border were buying plywood, flashlights and gasoline as Tropical Storm Dolly gained strength early today over the Gulf on its way to becoming a hurricane before it hits land.

Hurricane warnings were in effect for parts of the Texas and Mexico coasts, meaning hurricane conditions were expected in those areas by the end of today.

Forecasters at the National Hurricane Center in Miami said Dolly’s winds were expected to strengthen to hurricane force, which would mean at least 74 mph, before landfall.

Dolly was expected to make landfall later this week and bring with it high winds and up to 15 inches of rain and coastal storm surge flooding of 4 to 6 feet above normal high tide levels.

Emergency officials feared major flooding problems and urged coastal residents to prepare. Gov. Rick Perry activated 1,200 National Guard troops and other emergency crews.

 Shell Oil said it was evacuating workers from oil rigs in the western Gulf of Mexico. Shell said it didn’t expect its production to be affected by the storm.