The advisory is in effect until 7 p.m. Saturday night.
Weather Updates
For continual updates on the heat, check out News 8 Weather online or tune in to weather reports every 10 minutes on News 8.
With temperatures ranging between 100 and 105 degrees, the heat indices could rise to nearly 110 degrees.
You're urged to stay in an air conditioned area, out of the sun and check up on relatives and neighbors, especially the young and elderly.
Wednesday's temperature hit 105 degrees making it the hottest June 24th in Austin weather history and area residents broke another record just trying to keep cool.
June 24 marked an all-time peak demand of energy.
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Heat Advisory News 8's Bob Robuck explains the effects of a heat advisory and which groups of people are most susceptible.
Between 4 and 5 p.m., 2,518 megawatts of power surged through Austin power lines, according to Leslie Schneiweiss with Austin Energy.
Ironically, the previous record of 2,514 megawatts was set just last year during the typical peak of summer, but in August. Wednesday's record fell on only the third full day of summer 2009.
"On a normal summer day when temperatures are in the 90s, peak demand is usually somewhere between 2,200 and 2,400 megawatts. In the spring it's more like 1,900 megawatts," Schneiweiss said.
Austin Energy's original peak projection for this year of 2,542 megawatts had actually been lowered to 2,477 megawatts based on the downturn in the economy.
Experts advise residents not to worry, as more power is available if it's needed.
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•Use the following interactive tutorial to determine your household energy use, by clicking on the link.
"We have 2,700 megawatts of firm power generation, so we have plenty of power to keep Central Texans cool on these hot summer days," Schneiweiss said.
Texas' energy grid, maintained and controlled by ERCOT, holds a 17 percent reserve beyond their peak.
However, more record hot days in the triple digits ahead means a greater chance for another record of peak usage. There are some steps you can take to help lighten the power load.
The city recommends you leave lights off and avoid running power-hungry appliances like dishwashers and dryers during the hottest hours of 3-6 p.m.
Heat Advisory Impact
Due to the heat, the number of heat-related Emergency Medical Services (EMS) calls is up.
Children, the elderly, and those with fixed incomes are especially susceptible to extreme heat.
Austin/Travis County EMS has handled about 40 heat-related calls in less than two weeks. If the area continues to hover around these kinds of temperatures, EMS is going to get a whole lot busier.
And, so will the homeless shelters.
The Austin Resource Center for the Homeless, or ARCH, has gone into expansion mode.
It's making more space to add to its 175-person occupancy.
"We'll offer additional night's sleep to 40 men, 40 additional mats,” Amber Fogarty, of ARCH, said. “And, based on the numbers we've been seeing the last few nights, that should cover the need."
Shelters have a more detailed plan to help the homeless in the winter months, but that’s not the case in the summer. Shelter organizers are now rethinking that.
Voters' Guide For Central Texas Election Information, including a list of statewide candidates and links to county voting locations, click the link. Primary election day is March 2. The general election is Nov. 2.
Tuesday morning, a judge agreed to hear a divorce case between a same-sex couple. This is the second case heard in Texas. Do you agree with his decision to hear the case?