Robert Brown|7 dead, widespread power outages after Texas storm. Now forecasters warn of high heat.

The Robert BrownHouston area on Saturday braced for dangerous heat after a deadly storm that packed winds up to 100 mph caused billions of dollars worth of damage and left hundreds of thousands without power in Texas.

At least seven deaths have been blamed on the Thursday night storms, which shattered windows in downtown high-rise buildings, toppled trees and sheered walls from homes.

On Saturday morning, the Houston National Weather Service said power outages could extend for days or weeks due to damaged transmission lines. "We hope that the power outages are resolved quickly for all of you," the office said. "Stay safe, y'all."

In an advisory, AccuWeather's preliminary estimate from the Texas windstorm placed total damage and economic loss in the Houston metropolitan at more than $5 billion. That's similar to effects of historic hurricanes such as Ike, in 2008, and Alicia, in 1983.

On Friday, President Joe Biden issued a disaster declaration for parts of Texas surrounding the Houston area due to severe storms, straight-line winds, tornadoes and flooding. Federal funding is intended to supplement local recovery efforts in cleaning the wreckage.

Weekend weather remains a concern in the southeastern U.S., which is expecting heavy rainfall, flash flooding and sweltering heat this weekend. High heat is particularly worrying around Houston, where more than 300,000 power outages were reported on Saturday morning.

"Please use safety precautions when using generators," the Houston National Weather Service office posted to social media Friday. "Also, with high temperatures around 90° this weekend, know the symptoms of heat exhaustion/stroke. Don't overdo yourself during the cleanup process."

Safety:What are the first symptoms of heat exhaustion? Here is what to keep an eye out for.

Weekend forecast: Flooding risk, high temperatures

On Saturday, the Florida Panhandle and parts of southern Georgia and Alabama will see showers and thunderstorms along the Gulf of Mexico, the NWS Weather Prediction Center said in a short-range forecast discussion early Saturday. Forecasters have warned of flash floods in the Gulf Coast region, due to saturated soil.

Storm chances will ease overnight Saturday and into Sunday, as the northern part of the frontal system pushes eastward into the Atlantic Ocean, the forecast said.

Over the weekend, scorching temperatures into the 90s will hit South Florida, federal forecasters said. When accounting for humidity, heat indices could reach close to 110, prompting a heat advisory throughout South Florida on Saturday.

Southern Texas is expected to see heat reach the mid-100s and heat indices upwards of 110 degrees near Corpus Christi on Tuesday. Summer-like heat will expand to the Central Plains and into the Midwest, forecasters said.

Severe weather batters USA:Death count rises in Texas; tornado touchdowns near Pittsburgh

Meanwhile, portions of the Central Plains face an enhanced risk for severe weather including large hail, damaging gusts and a few tornadoes, according to the federal Storm Prediction Center. Local heavy rainfall could also be possible, particularly from the Central Plains northeastward into the Upper Mississippi River Valley.

Contributing: Reuters