Sep. 27--AUSTIN -- With temperatures on the rise and the power still out for much of East Texas in the aftermath of Hurricane Rita, another public safety crisis may be in the making.

The National Weather Service has issued heat advisories -- with dangerously high temperatures predicted -- in almost the entire area hit by the storm.

At the same time, hundreds of thousands of households could remain without electricity -- and without air conditioning or fans - - for weeks or months to come, officials said.

"It's almost like the perfect storm, where everything coming together is bad news," said Carol Biedrzycki, a consumer advocate. "People survived the hurricane. But if they still don't have electricity, they have to be careful because they might not survive the heat."

No heat-related deaths were reported Monday in the affected area, but officials were watching the situation very closely, a spokesman for the state's office of emergency management said. The military was setting up a mobile field hospital in Shelby County in East Texas.

Temperatures have already soared near 100 degrees and high temperatures are expected to continue through today from near Matagorda on the Texas coast into southwestern Louisiana.

With the stifling humidity left behind by the storm, the heat index in some areas could reach 117 degrees, according to the National Weather Service.

"We will evacuate anybody who has a special need or has a problem related to the heat," spokesman Ray Perez said.

Up to 1.2 million Texans had been without power, but that number had dropped to about 500,000 by Monday. Still, thousands of Texans - - particularly in rural areas -- could remain without power for a month or more.

Entergy, which serves the Beaumont area, reported the loss of major power lines running between Houston and Louisiana. The company began rolling blackouts Monday, a Public Utility Commission spokesman said.

Entergy has at least 10,000 workers on the job -- restringing and testing lines and clearing debris -- and will likely bring in more workers in the coming days. The company reported 255,000 customers still without power Monday afternoon.

Houston's Centerpoint Energy reported 149,000 customers without power Monday, and TXU Electric Delivery reported 40,000 without power.

PUC spokesman Terry Hadley said that some of the smaller electric cooperatives took severe hits.

In Jasper, all 20,900 Newton Electric Cooperative customers were without power. And around Kountze and Hardin County, 61,000 out of 64,000 Sam Houston Electric Cooperative customers were without service, he said.

"Anybody who can man a chain saw can help in the process of getting the power back on by clearing brush," he said.

ONLINE: National Weather Service Forecast Office, www.srh.noaa.gov/hgx