Hurricane Dolly left more than 27,000 electric customers without power in South Texas by midmorning Wednesday as bands of heavy wind and rain came ashore near Brownsville, just north of the U.S.-Mexico border.
The number of customers affected by the storm will grow Wednesday as the storm -- which strengthened as it neared the coast -- moves slowly onto land and across a large swath of South Texas served by American Electric Power's Texas utility, said spokesman Larry Jones.
"It's likely going to be a long day," Jones said.
Dolly was upgraded to Category 2, with winds of 100 mph as it slowed Wednesday morning before making landfall, the National Hurricane Center said.
AEP's outages were highest in Cameron County at the tip of Texas, where 24,400 customers, or 30 percent, lost power, according to a report at 11:45 a.m. New York time.
Power outages were also reported in the City of Brownsville, which is served by a municipal utility. Officials could not be reached immediately for comment.
Arrangements were made a day earlier for as many as 1,350 additional contractors to arrive after the storm to trim trees and restore power, AEP said.
In addition to high wind snapping trees and power lines, flooding is a concern, Jones said. "Flooding can contribute to outages and hamper repair work," he said.
The storm's predicted landfall and strength were unlikely to threaten offshore drilling rigs and production platforms in the Gulf of Mexico. U.S. crude oil prices hit 6-week lows Tuesday and fell further Wednesday to below $126 a barrel.
The hurricane center issued a hurricane warning for the southern Texas coast as far north as Corpus Christi.
Category 3 to 5 storms are considered the most dangerous but a Category 2 hurricane is still capable of causing damage to poorly built dwellings such as mobile homes.
The seaport serving Corpus Christi, a major U.S. oil refining center, was closed to ship traffic as a precaution.
The NHC said Dolly could dump 15 inches of rain on low-lying areas in South Texas and northeastern Mexico in coming days.
That has spurred concerns that torrential rains could overcome levees holding back the Rio Grande River and cause widespread flooding.
Texas Gov. Rick Perry put 1,200 National Guard troops on alert and issued a disaster declaration for 14 low-lying counties. State officials said they would not order mandatory evacuations unless Dolly reached Category 3, with wind speeds of over 111 mph .
Some 250 buses stood by in the inland city of San Antonio to evacuate coastal residents if needed.
Flooding a Major Concern
In Cameron County near the Mexico border, officials expected up to 20 inches of rain. "That's going to do a number on our county," said Johnny Cavazos, the county's emergency management coordinator.
Levees holding back the Rio Grande could fail if Dolly drives a surge of water from the mouth of the river inland, Cavazos said.
The levees held under similar conditions during Hurricane Beulah in 1967, but have "seriously deteriorated" since then, he said.
Texas State Police Captain Joe Gonzalez, who heads the combined emergency management system in Brownsville, said he was confident the levees would hold.
A platoon of Texas National Guard troops had deployed to the populous, flood-prone Rio Grande Valley, Gonzalez said.
Officials late Tuesday closed a causeway connecting Brownsville with the barrier island resort of South Padre Island. Many residents had already left.
In the Mexican city of Matamoros, across the border from Brownsville, police and military vehicles patrolled mostly deserted streets.
Authorities evacuated 23,000 people, but some were reluctant to leave, fearing looters.
"I didn't want to leave because I have been living in the same place for 40 years and I know what this is about," said Arturo Gutierrez, 55, a fisherman from the village of Chichonal who finally agreed to leave. "I am now going to the shelter because my wife forced me to."
The United States largely escaped the past two Atlantic hurricane seasons after being pummeled in 2004 and 2005, when a series of powerful hurricanes, including the catastrophic Katrina, ravaged Florida and the U.S. Gulf Coast.
The 2008 Atlantic hurricane season is already a month ahead of schedule. On average, the fourth tropical storm of the six-month season does not occur until Aug. 29. Dolly, this year's fourth, formed on July 20.