As Tropical Storm Alex gains strength, Gov. Rick Perry issued a disaster proclamation for the 19 counties expected to be hit later this week.

Hurricane watches were in effect for southern Texas and northern Mexico. Perry also ordered up to 2,500 Texas National guardsmen to be ready for deployment and activated disaster management teams around South Texas.

Locally, more than a dozen members of the Austin Fire Department and a few people from the Red Cross are mobilizing. The 15 Austin firefighters were sent to College Station, awaiting for further instructions. The Red Cross said it will deploy help Tuesday.

The storm is prompting hurricane watches for the lower Texas coast, from the mouth of the Rio Grande up to Baffin Bay (which is just south of Corpus Christi). A tropical storm watch is in effect from Baffin Bay up the middle coast to Port O’Connor. In Mexico, the government has also issued a hurricane watch that extends from the Rio Grande to La Cruz.

A hurricane watch means that hurricane conditions are possible within 48 hours, and a tropical storm watch means that tropical storm conditions are possible within 48 hours.

According to the 4 p.m. update from the National Hurricane Center, Alex was located about 520 miles southeast of Brownsville with sustained winds of 60 mph.

Moving to the north-northwest at a slow pace of 5 mph, the official forecast shows Alex curving generally towards the international border during the next few days. The tropical storm is expected to achieve Category 1 hurricane status Tuesday with wind speeds between 74-95mph.

Landfall would be possible Wednesday night at the earliest, according to the latest data. The National Weather Service said Alex could bring up to a foot of flash flooding and hurricane-force winds to South Texas by Wednesday. City officials in South Padre Island on Monday declared a local state of disaster in anticipation of Alex coming ashore.

Multiple computer models continue to insist on a more northern track that would increase the impact of wind, rain and surge on Texas. Steering wind currents could nudge the storm left or right.

In South Padre Island, city officials declared a local state of disaster and tourists had already begun canceling hotels for the busy July 4th weekend.

Stacy Stewart, a senior hurricane specialist at the National Hurricane Center in Miami, said the storm's center isn't expected to approach the area of the oil spill off Louisiana's coast. But Alex's outer wind field could push oil from the spill farther inland and hinder operations in the area.

Stay tuned to our tropical update at :48 past each hour on "Weather on the Eights" in addition to the latest on the weather homepage.

The Associated Press and Adam Krueger contributed to this report.