Autumn is here. This is what experts are saying about the weekend.

The calendar and nature will be in sync for the start of autumn, weather experts say.

A cold front will cross the Carolinas late Thursday, bringing an end to the September heat wave and possibly closing the door on 90-degree temperatures for this year.

In the wake of the front’s passage will be the coolest weather since May, according to meteorologists.

And the front is predicted to cross the area around the time that autumn officially begins – 9:03 p.m. Thursday.

One more day of 90-degree temperatures was forecast Thursday, but a big change is on the way, according to National Weather Service meteorologist Trish Palmer.

Thursday would be the 63rd day of 90 degrees, or hotter, this year for Rock Hill, but the National Weather Service’s Justin Lane said earlier this week that this week’s outbreak of 90s could be the last of 2022 for the Rock Hill region and the rest of the western Carolinas.

Forecasters say you’ll notice the difference when you walk out the door Friday morning.

Temperatures are expected to fall into the low 50s by daybreak Friday, and a wind gusting to 25 mph will make it feel even chillier.

“As we usher in fall, we’ll do so with an absolutely beautiful day Friday,” Palmer says, adding that high temperatures will be “a good 15-plus degrees cooler than Thursday.”

The forecast high Friday in the Rock Hill area is around 75 degrees.

Even cooler weather is predicted for Friday night, with a Saturday morning low forecast of 50. That would be the coldest since it dropped to 43 on May 10.

If you’re planning a Saturday outing, you might want to dress in layers. After the chilly start, temperatures are expected to rebound back near 80 degrees, forecasters say.

Palmer says we’ll have a one-day warm up Sunday, with highs expected to reach the mid 80s. But another cold front will cross the area Sunday night, and high temperatures next week are predicted to hit 80 on Monday and then the mid and upper 70s after that.

Your parched lawns and gardens might get a break in the coming days.

Forecasters say there is a small chance of a passing shower Thursday evening, and then a better chance (30 to 40 percent) of a shower or thunderstorm Sunday night.

Palmer says the long-term forecast remains murky. Computer models can’t agree on the future track of a potential tropical disturbance that is expected to strengthen this weekend in the Caribbean. Should that disturbance develop into a tropical storm, it could bring rain to parts of the Southeast late next week.

Autumn outlook

As for the long-term autumn outlook, the U.S. government’s meteorologists are predicting a good chance of above-average temperatures in October, November and December in the Carolinas.

And they say there’s an “equal chance” of above- or below-average precipitation.

Typically, much of the Carolinas’ early-autumn rainfall depends on possible tropical storms and hurricanes.

Here are average high and low temperatures for various dates this fall:

• First full day of autumn. High: 83; Low: 61.
• Halloween. High: 70; Low: 47.
• Last day of autumn. High 52; Low: 33.

This story was originally published September 22, 2022 at 2:03 PM.