A brief weakening of storm system Isaias will likely end with the squall hitting Florida as a hurricane, but still sparing South Carolina the brunt of the storm.
Isaias became a hurricane Thursday night, but weakened upon hitting the Bahamas on Saturday afternoon. Meteorologists said Saturday evening that they expected the system to regain hurricane status Saturday night or early Sunday morning as it creeps toward Southeast Florida.
But wind shear will likely weaken the system again as it heads up the Atlantic coast, leading meteorologists to predict Isaias would again revert to a tropical storm before reaching the Lowcountry on Monday. A tropical storm watch was in effect for that period in Beaufort, Berkeley, Charleston, Colleton and Dorchester counties.
Coastal communities can expect up to 6 inches of rain Monday, along with storm surge, rip tides and strong winds.
Isaias' slowing northwest crawl makes it difficult to predict flooding in the tri-county area, National Weather Service meteorologist Steve Rowley said. The system, pronounced ees-ah-EE-ahs, was traveling northwest at 9 mph as of 11 p.m. Saturday.
"It's the Monday night tide we need to keep an eye on, but Tuesday morning isn't off the table (for tidal flooding)," Rowley said. "We're watching the rain ... it's not just the saltwater we're worried about."
Initial models of storm surge are predicting as much as a 8 1/2-foot tide at Isaias' closest brush, which is 1 1/2 feet higher than the point where flooding starts in Charleston. But Charleston National Weather Service metorologist Mike Emlaw said that projection, like many, would likely change as the track becomes clearer.
"Even with a 7-foot tide, if it drops three to five inches of rain over a couple hours on top of that, it could cause problems," he said.
Charleston city staff worked Friday to clean drains and lowered water levels in Colonial Lake and Lake Dotterer.
The city has opted not to offer sandbag filling stations at this time but continues to monitor the storm’s progress, Emergency Management Director Shannon Scaff said.
“The reality of this thing is there is still some question of timing of its arrival,” he said. “It’s a measured approach but we are doing things to prepare.”
Right now, Charleston has 75,000 sandbags and a stockpile of 90,000 masks for emergency personnel.
The city was not planning to board up windows and hasn't encouraged local businesses to do that either.
But after reviewing the storm's forecast Friday night, city officials opened several downtown parking garages to residents free of charge to allow people to get their cars off the street in the case of flooding.
“We know timing is important because of high tides,” Scaff said. “We likely will see a lot of rainfall and that, with the alignment of the tides, will present a problem.”
The following garages will be open 8 a.m. Sunday to 8 a.m. Tuesday: Queen Street Garage, 93 Queen St.; Aquarium Garage, 24 Calhoun St.; Visitor Center Garage, 63 Mary St.; and St. Philip Street Garage, 93 St. Philip St.
Boats, trailers and golf carts are not allowed in the garages, officials said.
The Category 1 storm appears to be prevailing in its struggle against dry air and wind shear.
Meteorologists say Isaias could weaken a bit Saturday afternoon while passing over the Bahamian islands. However, the cyclone should restrengthen after the center moves back over the warm Gulf Stream Saturday evening.
Gov. Henry McMaster said Friday he was not planning to call a mandatory evacuation in advance of the storm. Emergency managers generally want an evacuation to commence 36 to 48 hours before a storm arrives, and that window was beginning to close.
Kim Stenson, director of the S.C. Emergency Management Division, said Charleston, Berkeley and Dorchester counties are considering shelter requests for people who are concerned their homes can't sustain high winds and have nowhere else to go.
If shelters open, screening will be in place to ensure nobody who is obviously ill enters in an attempt to stem the spread of COVID-19. The state has had to drastically modify its sheltering plan this year, and can keep only 20 percent of the people who need assistance in traditional shelter spaces, using hotels for the rest.
Though Isaias's impact to the Bahamas was limited to shorn shingles and tumbled trees, the islands are still recovering from Hurricane Dorian's devastation. Residents on Abaco who've been in temporary structures since September, along with Bahamians on the eastern end of Grand Bahama, were evacuated to safer shelter. Some areas lost power.
"People are doing the best they can to prepare, but a lot of businesses still have not repaired their roofs," said Paula Miller, Mercy Corps director for the Bahamas. "Even a lower level storm could really set them back."
And Bahamians are suffering from an onslaught of COVID-19, which further complicates evacuation safety.
In Florida, officials rushed to balance the dangers of coronavirus and storm impact with evacuation centers set up with distancing in mind. The state has one of the highest rates of coronavirus in the nation, with 2,183 known infections per 100,000 residents.
The storm's center was expected to hit the Sunshine State's southeast coast Sunday night, then travel along the east shore through Monday.
The Associated Press contributed to this report.