ATLANTA FORECAST

Friday: High: 90

Friday night: Low: 72

Saturday: High: 89

» For a detailed forecast, visit The Atlanta Journal-Constitution weather page.

The National Weather Service has issued severe thunderstorm warnings for Coweta, Fayette and Spalding counties until 6:45 p.m. Warnings for DeKalb, Newton and Rockdale counties expired at 6 p.m.

Traffic has gotten considerably worse since scattered downpours developed across the metro Atlanta area.

Trees are down in Cobb County, and traffic lights lost power along Haynes Bridge Road in Alpharetta, Channel 2 Action News reported.

A huge oak tree fell in someone's yard in east Cobb County at 25 Ancient Oak Court. (Credit: Channel 2 Action News)

Credit: Channel 2 Action News

icon to expand image

Credit: Channel 2 Action News

And it isn’t smooth riding for MARTA passengers on the Gold line due to a fallen tree between the Brookhaven and Lenox stations, MARTA said in a tweet. All train service north of Lenox station has been shut down, and there’s no estimated time for when it’ll reopen.

Multiple wrecks across the metro area are also causing problems, according to the WSB 24-hour Traffic Center.

There were heavy delays due to a crash on Ga. 400 South at Sidney Marcus Boulevard, the Traffic Center reported. In Sandy Springs, a downpour jammed both directions on Ga. 400 near Abernathy Road.

But at least there are fewer cows on the interstate now.

After six hours, crews cleared an overturned cattle hauler on the I-285 South ramp to I-20 East in DeKalb County. The three dozen cows trapped inside the truck were transported and the rig was towed away. Three cows were killed in the crash, officials said.

MORE: Tractor-trailer crash that killed 3 cows in DeKalb County cleared

RELATED: 10 cows killed in crash that closed I-75 for hours

One Cobb County roadway is closed for railroad replacement and won't reopen today. Piedmont Road between Canton and Morgan roads in Marietta is scheduled to reopen Saturday, the Cobb County Department of Transportation said.

Temperatures climbed into the 80s, which is only fueling these slow-moving scattered showers, Channel 2 Action News meteorologist Katie Walls said. It’s currently 82 degrees in Atlanta.

Atlanta will feel that moisture moving in as dew points continue to rise today.

“You can expect hot temperatures, and it’s going to be feeling even hotter because of that increased humidity, so there will be a bit of a heat index to consider this afternoon and into this weekend as well,” Walls said.

Downpours Friday should be contained to the afternoon and evening before the sun goes down.

“The rain chance is fairly minimal for today,” Walls said. “It could be one of those situations where you drive through a downpour and then within 10 minutes, it’s done.”

The chances of rain only go up from there, with Saturday at 30 percent and Sunday at 40 percent. However, Walls said these should be very isolated showers, so there’s no need to cancel outdoor plans. Like on Friday, the afternoon has the best chance of showers developing throughout the weekend.

The rain will bring temperatures back down to the 80s, according to the latest forecast.

“That’s not a washout by any means, but one of those weekends to be weather aware,” Walls said.

The same can’t be said for Monday and Tuesday. Both have a 60 percent chance of rain and thunderstorms, which will be more widespread both days, according to Channel 2.

» For a closer look at the weekend outlook and things to do in your area:

Cobb DeKalb | Gwinnett North Fulton

» For updated traffic information, listen to News 95.5 and AM 750 WSB and follow @ajcwsbtraffic on Twitter. 

» Download The Atlanta Journal-Constitution app for weather alerts on-the-go.