Editor’s Note: Are you in the path of the storm? Please share images with CNN if it is safe to do so.

Story highlights

Florida Gov. Rick Scott has declared a state of emergency in preparation for storm

Dominica PM says 20 people are dead, millions of dollars of property destroyed

CNN  — 

A day before a weak Tropical Storm Erika was predicted to arrive, Florida’s governor declared a state of emergency. He was worried about flooding from the storm, which has killed 20 people.

They died on the Caribbean island of Dominica as torrential rains burst the banks of rivers and streams with turbulent force. Erika swept away even more people, who are still missing, authorities there said.

As tropical storms go, Erika’s winds are not impressive. As it staggers over Cuba on Saturday, it is predicted to weaken to a tropical depression, but Florida Gov. Rick Scott is leery of potential heavy rainfall.

Shot August 27, 2015 on island of Dominica
Tropical Storm Erika blamed for deaths in Dominica
01:41 - Source: CNN

“We don’t know how much land it’s going to go over,” Scott said at a news conference Friday. “We don’t know how much water we’re going to get.”

Though the National Hurricane Center forecast calls for patches of strong thunderstorms, as Erika crawls along Florida’s western coastline early this week, the Tampa area in particular could be vulnerable to high water, as it is still saturated from storms a couple of weeks ago.

Track Erika’s path

Grief among ruins

Despite the sagging winds, the torrents that pelted Dominica, located just north of Martinique, are an unforgiving reminder that flooding is the number one storm killer.

Dominica was deluged by 12 inches of rain in fewer than 10 hours, CNN meteorologist Chad Myers said. The waters also pushed walls of mud down hills, destroying homes and livelihoods.

They have cut off the village of Petite Savanne, where rescuers are searching for mudslide victims, with other countries in the region providing helicopters and other assistance.

Images of loss – swamped villages and washed out roads and buildings – flooded social media. People in Dominica are bereft, the nation’s Prime Minister said Friday night.

“Rest assured, my brothers and sisters, you are not alone in your period of mourning in your period of pain, in your period of suffering and anxiety,” Prime Minister Roosevelt Skerrit told the nation.

Worst damage seen

Repairing infrastructure will cost tens of millions; the damage will set the island back for two decades he said.

The Prime Minister, who was in Saint Lucia when the storm first hit, deflected criticism that the government didn’t issue proper warnings to its 70,000 citizens.

“There is no need to indulge in blaming others for what has happened in Dominica,” he told the nation. He said forecasters had been focused on the larger islands in the Caribbean and Florida.

Trisha Scotland has watched many black storms rage over Dominica in her lifetime, but this is the worst damage she’s ever seen.

“I’ve experienced at least six to seven hurricanes. I’m not even counting the storms. I’m not even counting the depressions,” Scotland said.

She walked 6 miles from her home in Jimmit to the capital, Roseau, to check on her mother’s business, photographing the devastation along the way.

Approaching South Florida

Early Saturday, Erika was between Haiti and Cuba. The storm was expected to drop 3 to 6 inches of rain, in localized spots up to 10 inches.

“These rains could cause life-threatening flash floods and

mud slides,” the hurricane center warned. Erika’s maximum sustained winds were 45 mph, with higher gusts.

As Erika approaches South Florida, it is expected to weaken to a depression then possibly pick back up to tropical storm strength.

The U.S. Coast Guard has warned boaters and cargo ships in Key West on Friday to prepare for the possibility of sustained gale-force winds.

Tropical storms and hurricanes: Fast facts for 2015

CNN’s Steve Almasy contributed to this report.