Residents are already experiencing extreme weather, with severe storms hitting the Dallas-Fort Worth area in late May and sporadic storms continuing into June.
But once the storm clouds clear, the sweltering Texas summer sun will emerge.
While North Texas residents take refuge in public pools, splash pads, cooling centers or their own home air conditioners, a common question remains: When will we see the first day temperatures exceed 100 degrees?
When will temperatures reach 100 degrees in the summer of 2024?
As with most weather forecasts, National Weather Service officials say it’s hard to give a definitive answer.
“We’re meteorologists, but we don’t know any more about these things than other people, especially when it comes to things that could happen in the weeks and months ahead,” said Daniel Huckaby, a meteorologist with the National Weather Service in Fort Worth.
According to the Weather Service, the average date for the first time temperatures to exceed 100 degrees is July 1. This average is based on data going back to 1899.
But Huckaby predicts that because wet ground and healthy vegetation often result in cooler daytime temperatures, this spring’s excess rains will likely mean the first day with temperatures above 100 degrees will likely be after July 1.
Still, the first day with temperatures over 100 degrees could come sooner. Huckaby says a weather phenomenon called a high-pressure ridge (a high-pressure system between two and five miles above the ground) is what causes the summer heatwaves. This usually happens around the summer solstice in June, which is June 20 this year. If it happens as scheduled, he says, the first day with temperatures over 100 degrees could happen in June.
How many days does it get above 100 degrees in D-FW?
On average, Dallas-Fort Worth experiences triple-digit temperatures 17 days a year.
The averages are based on the same data set, stretching back to 1899, but data from more recent periods reflect an increase in days with temperatures above 100 degrees and warmer temperatures.
Fifty years ago, D-FW averaged 15 days a year that were over 100 degrees, Huckaby said. In the 30-year period from 1991 to 2020, an average of 20 days a year reached 100 degrees, he said.
In 2023, temperatures reached 100 degrees 55 times.
Huckaby said the NWS issued a forecast predicting a warmer-than-normal summer for 2024, following a trend of rising summer temperatures over the past few years. Last summer was the second-hottest in Dallas history and the third-hottest in Dallas-Fort Worth.
These hot summers are partly due to climate change, but also due to positive feedback loops that reinforce warmer temperatures, which can intensify weather patterns like ridges and droughts that already cause warmer weather, leading to more warming, he said.
“Today’s weather is related to both yesterday’s and tomorrow’s weather,” Huckabee said in an email. “This correlation can extend to longer time scales. If it were as random as the Las Vegas games, you’d expect several hot summers to be followed by a cool summer. But weather doesn’t work that way, because weather is not particularly random.”
Here are some things to remember during the Texas summer.
When has D-FW ever reached 100 degrees before?
Summer is getting hotter with more days reaching over 100 degrees, but the onset of those high temperatures appears to be delayed, Huckaby said.
A century ago, the average first 100 degree day fluctuated between June 23 and 26. Huckaby said a lack of data played a role, but it has been more stable over the past 50 years. During that time, the average moved from June 29 to July 1. In the 30-year average from 1991 to 2020, the first 100 degree day occurred even later, on July 3.
“At first glance, it’s unclear why this is the opposite of what was expected, but it may have something to do with the trend towards increased precipitation in spring,” he said.
Will we see more days with temperatures exceeding 100 degrees?
John Nielsen Gammon, a professor of atmospheric sciences at Texas A&M University, helped write the report, which looked at past and future weather trends in Texas from 1900 to 2036. The initial report was released in 2021 but was updated with additional data in 2024 to refine the report’s projections.
To examine days exceeding 100 degrees, the report tracked trends in four regions of Texas: Coastal, Northwest, Northeast and South Central. Over the past 50 years, the number of days exceeding 100 degrees has nearly tripled in three of the four Texas regions, according to the report. The Northeast region, which includes Dallas-Fort Worth, did not follow the trend, but that’s because the region has experienced heat before, Nielsen Gammon said in an email. Future trends in the Northeast region are expected to be similar to the rest of the state, he said.
By 2036, the number of days with temperatures exceeding 100 degrees will be nearly four times more common than in the 1970s and 1980s, according to the report.
Nielsen-Gammon expects that urban areas will experience more days with temperatures exceeding 100 degrees due to the urban heat island effect. Cities are often hotter than the surrounding countryside because urban infrastructure traps heat. Similarly, cities have less exposed soil and vegetation to cool the surrounding air.
What’s a North Texan to do in the heat?
Nielsen Gammon said steps to stay healthy in the heat include avoiding excessive exercise and staying well hydrated, which is of greater concern for people who spend most of their day outdoors.
“It’s important that workers have access to extended breaks to escape the heat and have plenty of fluids,” he said.
Nielsen Gammon also noted the challenges for people without air conditioning. Cooling down at night allows the body to recover from the heat and prevent major health problems. For those without access to air conditioning, cooling centers can help them weather the heat and avoid heat-related health problems.
