Texans know that summer has a tendency to overstay its welcome. This year, fall has evaded Dallas-Fort Worth even longer than normal.
For over two weeks, the high temperature has stayed between 87 and 92 degrees, according to the National Weather Service’s Fort Worth office. It’s been significantly warmer than normal – during the same period, the high would be expected to fall from 86 degrees to 79 degrees.
John Nielsen-Gammon, the Texas state climatologist based at Texas A&M, said the first night in the 50s is usually a good indicator of fall’s arrival for North Texas. Historically, that temperature has arrived around Sept. 21, almost exactly lining up with the autumnal equinox. D-FW has yet to see temperatures dip that low this year.
If a low in the 50s still hasn’t arrived by Thursday – which is not predicted in the forecast – this year will see the latest arrival of the fall chill ever recorded.
D-FW Weather Wise
It’s not the first time that the first half of autumn has been hotter than expected. Over the last 10 years, highs and lows in September and October have frequently been above normal, by about 2 degrees on average. That “normal” benchmark is calculated by the weather service as a 30-year average, from 1991-2020.
Nielsen-Gammon said this warming trend is broadly a result of human-caused climate change, among other factors. As Texas and the globe continue to get hotter, he said that warming will be felt in every season.
The latter arrival of fall may become permanent, but Nielsen-Gammon also pointed to recent weather patterns to explain the absence of an early-October cold front.
“A lot [of weather] is influenced by the particular pattern of the jet stream, where it happens to dip northward or dip southward,” he said.
The jet stream is a narrow band of strong wind currents that blow from west to east around the planet. When its pattern is farther to the north, as it has been recently, Texas experiences hotter and drier weather, Nielsen-Gammon said. That has allowed a stationary high-pressure system to sit over the region.
Those drier conditions have persisted since early September. In the last month, DFW International Airport has received only 0.42 inches of precipitation, compared to the normal of about 3 inches.
Nielsen-Gammon said the last 30 days have been the fifth driest on record for most of Texas’ major metro areas. Farther west, conditions have been more normal.
There’s some exciting news for fall lovers, though: Change is coming.
A cold front is expected to move in this weekend, bringing notable rain chances and a significant temperature drop for Sunday. According to the weather service, rain chances are strongest Saturday afternoon and evening, with a high of 83 degrees expected on Sunday.
“It looks like things turn a bit cooler later in the month,” Nielsen-Gammon said. “So fall will start eventually.”