Tropical Storm Tammy likely will have done her worst by noon today after surprising the Lowcountry with rain, gusts and the threat of tornados Wednesday. Don't look now, but another one might be right behind her.

Either way, weather will be nasty through the weekend.

A mass of weather between Cuba and the Yucatan Peninsula in Mexico could become a tropical depression before bringing squally weather to Florida and then overland into South Carolina by late Friday.

"That's what we expect at the moment," said National Hurricane Center meteorologist Chris Sisco on Wednesday.

"It may actually have an attempt at spinning up another tropical system," said meteorologist Gerald Mohler of AccuWeather, a private forecasting company. It could get strong enough to get the 20th name of the season, Vince. "Yeah, I can see that (happening)."

Tammy was expected to drop up to 3 to 5 inches of rain on the Lowcountry and as much as double that in some spots. Its remnants will keep raining in an onshore wind into the weekend, and the next tropical system will feed into that.

"There are several bouts of heavy rain still ahead of us," said meteorologist Steve Wilkinson of the National Weather Service's Charleston office. "We should dry out early next week."

The storm also brought coastal flooding and a high risk of rip currents at the beaches. But, for the most part, it brought needed rain.

It struck just as State Climatologist Hope Mizzell was ready to reconvene a drought response committee after a relatively dry summer.

"We were that close. It's a welcome rain," she said Wednesday. "We feel pretty confident it's going to be a statewide soaker. But for coastal locations, it's going to be more rain than is welcome."

On Wednesday, nine city of Charleston drainage crews and four jet-vacuum trucks raced against the storm to about a dozen major, usual-suspect flooding areas from the Market to West Oak Forest in West Ashley.

The city has a drainage system that in parts dates to the 1880s. It has a million feet of ditches and a recurring problem of people dumping debris that clogs them, said assistant storm water superintendent Butch Pannell.

"When you're below sea level, and much of Charleston is, and the tide starts coming in, you've got nowhere to go," he said. "My end of it is to try to keep the water flowing as fast as I can." High tide today comes at 10:21 a.m.

In early afternoon, the tropical storm abruptly swooped down on the peninsula, the first feeder band coming in off the ocean as a black cloud swallowed buildings and spewed wind and rain.

Charleston, Dorchester and Colleton raised their operations alert level to prepare for the storm.

By evening, a 54 mph gust had smacked Folly Beach, and a 45 mph gust blew through downtown Charleston, according to the National Weather Service in Charleston. It had dropped 1-1/2 inches of rain in some parts of the Lowcountry.

South Carolina Electric & Gas Co. reported late Wednesday that about 3,500 customers were without power in the greater Charles-ton area. That number was expected to fluctuate.

"We're getting power restored to our customers; while you still have these strong wind gusts, additional customers are going out," said Jodie Roberts-Smith, a spokeswoman for the utility.

The National Weather Service reported that nearly all of the Edisto area had lost power late Wednesday and was being hit with tropical-storm-force winds.