Humberto made landfall on the Texas coast early Thursday shortly after strengthening into a Category 1 hurricane, the National Hurricane Center said.

The center of the storm crossed the Texas coast just east of High Island at about 2 a.m. (3 a.m. ET) with maximum winds of 85 mph (135 kmh). Humberto -- a slow mover -- is primarily going to be a rainmaker, CNN Meteorologist Chad Myers said.

"It will dump a lot of rain in one place, and it will move a little bit and dump a lot more rain and move a little bit," Myers said.

Ahead of the storm, Texas Gov. Rick Perry activated state resources, including 50 vehicles, 200 soldiers, six Blackhawk helicopters and two swift-water rescue teams.

"Some areas of our state remain saturated by summer floods, and many communities in this storm's projected path are at high risk of dangerous flash flooding," Perry said.

At 1:15 a.m. ET, Humberto's center was about 20 miles east of Galveston, Texas, and about 15 miles south of High Island, Texas, the National Hurricane Center said.

It was moving north-northwest at near 8 mph (13 kmh). Hurricane-force winds extended only about 15 miles from the center of the storm.

"Little additional strengthening is expected prior to landfall," forecasters said.

A hurricane warning was issued from east of High Island to Cameron, Louisiana.

A Category 1 hurricane, the weakest categoy, has winds of 74 mph or greater. The storm is poised to dump more than a foot of rain over some already-soggy parts of Texas and Louisiana.

"On the forecast track, the center should be crossing the upper Texas coast within the warning area early Thursday," forecasters said.

The center of the storm turned northward rather than making landfall near Galveston on Wednesday night, CNN Meteorologist Chad Meyers said. That gave the storm more time over the warm Gulf waters -- meaning more time to strengthen prior to landfall.

The storm emerged as a tropical depression late Wednesday morning. By 2 p.m. ET, the hurricane center in Miami announced Humberto had achieved tropical storm status.

A tropical storm warning was in effect from east of Sargent, Texas, to Intracoastal City, Louisiana. An earlier warning from Sargent westward to Port O'Connor, Texas, was discontinued.

The warning means tropical storm conditions, including winds of at least 39 mph, are possible within 24 hours.

Forecasters predicted the storm could dump 5 to 10 inches of rain along the already-saturated Texas and Louisiana coasts, with isolated amounts of up to 15 inches possible. Humberto could bring storm surges of 3 to 4 feet above normal tides near and to the east of where it makes landfall.

In addition, isolated tornadoes are possible overnight in southeastern Texas and southwestern Louisiana, the hurricane center said.

"I urge all Texans to heed the warnings of their local leaders and take all possible precautions to stay out of dangerous situations as this severe weather continues," Perry said.

The region has seen higher-than-normal rainfall throughout the summer, and Tropical Storm Erin dumped about 6 inches of rain on the Houston area after it hit near Corpus Christi in mid-August.

Flooding triggered by the heavy rain was blamed for at least one death.

Humberto will be the third hurricane to hit the region this year. Last week, Hurricane Felix barreled into northern Nicaragua as a powerful Category 5 storm, claiming at least 65 lives. Three weeks ago, Hurricane Dean slammed into Mexico's Yucatan Peninsula, also as a Category 5.

Separately, the hurricane center said Tropical Depression Eight had formed in the Atlantic Ocean and could become a tropical storm Wednesday night or Thursday morning.

As of 11 p.m. ET, the depression's winds were near 35 mph (55 kmh), just short of the 39 mph needed to become a tropical storm.

The center of the depression was located about 1,005 miles east of the Lesser Antilles, and it was moving west at near 12 mph (55 kmh). If it becomes a named storm, it will be assigned the name Ingrid.

"It has a lot of time to get bigger," Myers said.