Temperatures were expected to reach 90 degrees this week for the first time since September, although the thermometer had hit only 87 at D/FW Airport as of 4 p.m. Wednesday.
The last time the official North Texas temperature hit the 90s was Sept. 27, 2009, when a high of 95 was recorded, according to National Weather Service data.
Temperatures are rising because a cap of dry air was firmly positioned over North Texas, said Eric Martello, a meteorologist with the weather service office in Fort Worth. Tuesday's high was 85 degrees.
A weak cold front pointed south toward the region was not expected to degrade the cap, and there were no southeasterly winds to dampen the area with moisture from the Gulf of Mexico.
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"It's very dry out," Martello said. "It's a westerly flow right off the deck here, and a westerly flow is a dry flow."
The record high for May 5 is 95 degrees in 1984.
Thursday's high was also expected to be around 90, beneath mostly sunny skies, the weather service said.
Friday will be mostly sunny, but the forecast calls for the arrival of a more robust cold front. That system will push temperatures back into the high 70s, although 80 degrees is possible, the weather service said.
Saturday will be partly sunny with a high around 76 and a 20 percent chance of showers.
Sunday also has a 20 percent chance for showers because southeasterly winds will return to the region, packing a new supply of gulf moisture.
Monday and Tuesday are expected to be partly cloudy with highs near 90 both days, according to the long-range forecast.