What's the best temperature to set your thermostat during Texas summers? What experts say

It’s a familiar debate among families and roommates: What’s the ideal temperature to set the thermostat? In a Texas summer, that discussion can get heated — fast.

And while it may still feel early in the season, the scorching temperatures say otherwise.

Just in time for the start of summer on June 20, a heat wave is expected to scorch a large section of the United States, forecasters said.

According to the Weather Prediction Center, the heat will begin June 20 across the Plains, then expand over the weekend across portions of the Midwest and Great Lakes. The heat is then expected to shift and persist across the Ohio Valley, Northeast and Mid-Atlantic late this weekend through next week.

"The hottest weather of the season so far will build over the central United States later this week with widespread highs in the 90s and some 100-degree readings in store from the Rockies to the Mississippi Valley," said AccuWeather meteorologist Alex Sosnowski in an online forecast June 15.

A few rare locations could approach or top 100 degrees, including Denver, which happens only twice a year on average, said Weather.com meteorologist Jonathan Erdman, who added that "New York City and Philadelphia could also flirt with the century mark during the peak of the heat wave next week."

In Texas, temperatures are expected to soar well above 100 degrees, according to local weather service offices.

Extreme heat is the deadliest weather-related hazard in the United States, claiming more lives each year than hurricanes, floods or tornadoes, making it crucial to prepare ahead of time and know how to care for yourself and others.

As the heat intensifies, Texans must balance staying cool with conserving energy. With triple-digit temperatures expected, the temptation to crank up air conditioning is high, but it’s important to be mindful of energy usage to avoid straining the state’s power grid.

What temperature should I set for my AC this summer?

As Texas experiences soaring temperatures, other factors can contribute to thermostat preferences, such as:

• What feels comfortable to you and the other people in your household.
• The health conditions of people in your household.
• How well your home is insulated and otherwise protected against heat.
• What other cooling methods you use (floor fans, ceiling fans, closed curtains/shades, etc.).
• How much you're willing to pay on your electric bill.

Is 78 the 'magic number'?

The U.S. Department of Energy has lauded 78 degrees as the ideal temperature for the summer, providing the most savings without too much discomfort.

Should I turn my air conditioner off at night and open the windows?

If you don't have central air conditioning, opening windows and turning on fans is a good alternative. However, it might be counterproductive if you use AC during the day.

Depending on humidity, leaving windows open can let in hot, moist air. In addition to being uncomfortable, this air can be absorbed by carpet and furniture, increasing the possibility of mildew.

Plus, nighttime temperatures are warming faster than daytime temperatures, meaning you may not get the relief you expected. It might not be worth opening windows at night if you're trying to conserve energy and avoid running the AC, as temperatures may remain uncomfortably high even after sunset.

Opening windows could also let out the cooler air that was circulating throughout the day, which defeats the purpose of trying to keep the interior cool. Instead, it might be more effective to set the thermostat a few degrees higher during the night, rather than allowing the cool air to escape.

Should I turn off my air conditioner if I leave for work or vacation?

Texas Energy recommends setting your thermostat at 85 while away to save up to 10% on your yearly costs.

However, the duration of your absence and personal preferences will determine whether this is worthwhile. Depending on outside temperatures and the size of your home, it might take some time for conditions to become comfortable again.

Keep the home cooler for people more susceptible to heat

Older adults are more prone to heat stress, according to the Centers for Disease Control. They don't adjust as well to temperature changes, they're more likely to have a chronic medical condition that changes their normal responses to heat, and they're more likely to take prescription medicines that affect the body's ability to control its temperature.

Older people are also more prone to Alzheimer's disease and other dementia-related illnesses, and scorching heat can be even more dangerous for people who might not notice that they're overheating, might not understand what it means, might have impaired judgment, or might not be able to tell anyone about it.

Best ways to keep your home cool and save energy

• Replace your air filter regularly: A dirty filter reduces airflow and makes your system work harder. Check it monthly during summer.
• Use a programmable or smart thermostat: Set higher temps when you're away or asleep to save energy without sacrificing comfort.
• Close blinds and curtains during the day: Blocking sunlight helps reduce indoor heat, especially on south- and west-facing windows.
• Seal windows and doors: Prevent cool air from escaping by sealing any leaks with caulk or weather stripping.
• Limit heat-generating activities: Use the oven, stove or dryer during cooler times of day — or opt for an air fryer, microwave, toaster oven or grill.
• Don't leave ceiling fans on: They help rooms feel cooler, but they don’t lower actual temperature — so turn them off when leaving the room.