Good news. Today and the rest of the week should be relatively cooler.

While the National Weather Service may issue another heat advisory for today, high temperatures are expected to drop to 94 degrees and to 92 on Thursday. And high temperatures are expected to be around 90 degrees for the rest of the week, according to the Weather Service. There is a chance of showers and thunderstorms on Thursday and Friday.

Charleston got a cruel double-whammy Tuesday, when record high temperatures coincided with the longest day of the year and the official start of summer.

It was the second consecutive day that temperatures hit 100 degrees. On Monday, the temperature at the airport reached 102 degrees, breaking the record for that date. On Tuesday, the airport's high of 100 degrees tied the daily record set in 1990. Downtown Charleston reached 100 degrees Monday, tying a daily record set in 1928, but only reached a high of 96 Tuesday.

The Weather Service issued a heat advisory Tuesday for most of South Carolina and part of bordering Georgia that lasted until 8 p.m.

In order to reduce the risk of heat-related illness, residents were urged to stay inside air-conditioned areas, drink plenty of fluids and check in on relatives and neighbors.

Residents, apparently, took heed.

On Monday, Charleston County EMS was dispatched to 11 heat-related emergencies, EMS Director Don Lundy said. On Tuesday, it had only six such calls.

"I think after that first day, people took it to heart," Lundy said. "They stayed home, stayed inside and they hydrated."

The Medical University of South Carolina's emergency room treated some patients suffering from dehydration Tuesday, but spokeswoman Megan Fink said the number was not extraordinary for this time of year. The ERs at downtown Roper Hospital, Trident Medical Center in Goose Creek and St. Francis in West Ashley had seen no patients with heat-related illnesses by late afternoon.

John Hart, owner of Hart & Son Roofing on Johns Island, said his crew of four is taking extra precautions due to the record heat.

"We're trying to get on the job as early as we can and working shorter work days," he said. "My guys are only working four-and-a-half to five hours a day, taking frequent breaks and drinking plenty of fluids."

Chris Coleman, president of C & C Heating & Air Conditioning in Mount Pleasant, said his company normally gets 25 to 30 calls daily but is now getting 40 to 50.

"Yeah, it's been a little crazy the last two days," he said.

Weather Service meteorologist Pete Mohlin said the recent drought is largely to blame for the heat. "It's mainly because we've had such a dry spring so far, and we haven't really seen much in the way of cooling showers and thunderstorms," Mohlin said. He added that the sea breeze has been slow moving inland.

Usually, Charleston's highest average temperatures are reached in late July and early August, but 100-degree weather even then is out of the ordinary.

Luckily enough for kids, families or any other Charlestonians needing relief, Splash Zone was reopened for "Two for Tuesday." A water main break had closed the James Island water park Sunday and Monday to allow electrical components to dry.

David W. MacDougall contributed to this report. Reach Ryan Quinn at 937-5906.