Fall arrives Wednesday night but temperatures will stay warm in Dallas-Fort Worth

When fall returns to North Texas at 10:09 p.m. Wednesday, the mercury should be in the mid-to-lower 70s, headed for a Thursday high temperature of about 90 degrees.

That's two notches above September's daily average of about 88 degrees.

But with temperatures a few degrees above normal for the past couple of weeks, some North Texans may be wondering when the heat will finally break.

Pinpointing that date on a calendar, however, is challenging.

A few days ago, National Weather Service forecasters predicted temperatures would stay in the low 90s this week, then drop -- maybe.

On Monday, however, computer models were at odds about whether an autumn chill would arrive next week.

"Some (models) show decent cooldowns, but others continue to show it staying fairly warm," said Dennis Cavanaugh, weather service meteorologist in Fort Worth.

Forecasters last week were watching a cold front in the northern plains to see if it might drag cooler air into Texas by the end of this week.

That system had weakened by Monday.

However, an upper-level low pressure system was brewing in the Pacific Ocean. It might reach the Pacific Northwest by Thursday afternoon, Cavanaugh said.

"It's not a question of how strong it will be but, rather, where it will go," he explained. "If it moves south, we could see a pretty decent chance for a cold front.

"And if that were to happen, lows in the 50s would not be out of the question."

But, he stressed, that possibility, as of Monday, was "far from certain."

"It's just hard to tell for the next week," he added. "That's 150 hours away."

If the temperatures don't drop next week, it may not be much longer before they do.

The first day of fall, Wednesday, marks the autumnal equinox -- when the Sun is directly over Earth's equator.

Daylight-savings time, which began March 14, ends Nov. 7. And the next change of season will be when winter arrives at 5:38 p.m. Dec. 21.

Winter's a long way away. Tuesday's high is expected to reach 92 degrees around 4 p.m., according to the weather service forecast. The readings at that time, however, were 87 degrees in Fort Worth and 90 at DFW Airport and Dallas.

Tuesday and Wednesday will be 89 degrees with a 20 percent chance for thundershowers both days and on Thursday.

Temperatures will edge closer to 90 degrees Thursday and Friday, but then slide back to the high 80s Saturday and Sunday.

A 30 percent chance for showers has been added for Friday night and Saturday.

Rain chances slip to 20 percent Saturday night and Sunday, according to the forecast.

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