Rising Nighttime Temperatures in Texas: A Growing Concern

It’s hard to avoid triple-digit temperatures during the summer months in Texas. But most people expect a respite from the heat at night. However, new research shows that relief may be less available, particularly in the Southwest. The analysis by Climate Central, a climate education nonprofit, shows that nationwide, average summer nighttime lows have risen just over 3 degrees in the last 50 years.

In Texas, that trend is most clearly exemplified in El Paso, where the average summer minimum temperature rose almost 9 degrees from 1970 to 2024. This significant increase in nighttime temperatures can have severe consequences for the health and well-being of residents, especially during the hot summer months.

In drier climates, changes in local greenhouse gas concentrations can have a particularly noticeable effect on night temperatures, according to John Nielsen-Gammon, Texas state climatologist. Nielsen-Gammon pointed out water vapor is also a greenhouse gas, which has likely risen in the region due to increased irrigation. This combination of global climate change and local climate change is contributing to the rising nighttime temperatures in Texas.

The Impact of Rising Nighttime Temperatures

He also pointed to rising night temperatures in major urban areas: D-FW and Houston also saw increases above the national average — 5 and 5.8 degrees, respectively. He said the change is largely expected as it follows the urban heat island effect, which is particularly impactful as large cities have grown. The urban heat island effect occurs when built-up areas, such as cities, absorb and retain heat from the sun, making them warmer than surrounding rural areas.

“It’s a combination of global climate change and local climate change,” he said. This means that the rising nighttime temperatures in Texas are not just a result of global climate change, but also due to local factors such as urbanization and changes in land use.

Why is Nighttime Heat Dangerous?

Being exposed to high temperatures for an extended period can cause cumulative stress on the human body, according to the World Health Organization. Higher nighttime temperatures extend that period of stress, ultimately increasing the risk of illness and death from heat exposure. This is particularly concerning for vulnerable populations, such as the elderly, young children, and people with pre-existing medical conditions.

A 2017 study found higher nighttime temperatures add to the mortality risk in people below age 65. The study also said warm nights preceded by a hot day have the greatest health impacts. In 2023, which was one of the hottest years on record, 563 heat-related deaths were recorded in Texas, according to the Texas Campaign for the Environment. Last year’s first heat-related fatality was recorded in August with the death of a 79-year-old Dallas County woman, who had no pre-existing medical conditions.

What Steps is Dallas Taking?

The city of Dallas, in partnership with electricity provider Reliant, has opened two Beat the Heat cooling centers to provide a space for residents to take refuge in the summer months to reduce the need for home electricity. The centers — West Dallas Multipurpose Center at 2828 Fish Trap Road and Martin Luther King, Jr. Community Center at 2922 Martin Luther King Jr Blvd. — will be open to all residents during normal business hours and will have snacks and beverages available, according to officials.

All public buildings are also open to residents during regular business hours to find relief from the heat, including public libraries and recreation centers. The public-private partnership, in its 16th year, will also sponsor the distribution of 260 evaporative cooling units. Residents can contact either community center to apply. These centers do not directly address nighttime heat, as they are not open late, but they can help prevent the risk of heat-related illness since residents can use city facilities to ensure they don’t experience prolonged exposure.

Deputy Mayor Pro Tem Adam Bazaldua said at a news conference for the “Beat the Heat” kickoff that if nighttime temperatures soar, the city will open inclement weather shelters. For that resource to become available, the National Weather Service must forecast the temperature to reach 90 degrees in Dallas between the hours of 10 p.m. and 8 a.m. the next day.

“We recognize that not all residents have access to cool air in their homes during the Texas summer, due to many uncontrollable factors like not having central AC systems or increased costs of electricity,” Bazaldua said. “Heat exhaustion and heat stroke are very real dangers, but they are preventable.”

Prevention and Preparedness

To beat the heat, residents can take several precautions. Staying hydrated by drinking plenty of water, avoiding strenuous activities during the hottest part of the day, and wearing light, loose-fitting clothing can help prevent heat-related illnesses. Residents can also use city facilities, such as public libraries and recreation centers, to find relief from the heat.

For more tips to beat the heat, check out our guide here. By taking these precautions and being aware of the risks associated with rising nighttime temperatures, residents can stay safe and healthy during the hot summer months.

Conclusion

Rising nighttime temperatures in Texas are a growing concern, with significant increases in average summer nighttime lows over the past 50 years. The combination of global climate change and local climate change is contributing to this trend, with major urban areas such as D-FW and Houston experiencing increases above the national average. The city of Dallas is taking steps to address the issue, including opening cooling centers and distributing evaporative cooling units. By being aware of the risks and taking precautions, residents can stay safe and healthy during the hot summer months.

Frequently Asked Questions

Q: What is the urban heat island effect?

A: The urban heat island effect occurs when built-up areas, such as cities, absorb and retain heat from the sun, making them warmer than surrounding rural areas.

Q: How can I prevent heat-related illnesses?

A: To prevent heat-related illnesses, stay hydrated by drinking plenty of water, avoid strenuous activities during the hottest part of the day, and wear light, loose-fitting clothing.

Q: What are the symptoms of heat exhaustion and heat stroke?

A: The symptoms of heat exhaustion include heavy sweating, pale and cool skin, faint or weak pulse, and nausea or vomiting. The symptoms of heat stroke include high body temperature, confusion, slurred speech, and loss of consciousness.

Q: Where can I find relief from the heat in Dallas?

A: You can find relief from the heat at public buildings, such as libraries and recreation centers, which are open during regular business hours. You can also visit the Beat the Heat cooling centers, which are open to all residents during normal business hours.