SAN JUAN, Puerto Rico (AP) — Tropical Storm Franklin churned through the Caribbean Sea Tuesday as authorities in Haiti and the Dominican Republic warned residents to prepare for landslides and heavy floods.

The storm was centered early Tuesday about 255 miles (415 kilometres) south of Santo Domingo, the capital of the Dominican Republic, and had maximum sustained winds of 50 mph (85 kph). It was moving northwest at 3 mph (5 kph) and was expected to turn northward.

Franklin was expected to strengthen before making landfall early Wednesday in Hispaniola, the island shared by Haiti and the Dominican Republic.

The storm is forecast to drop up to 10 inches (25 centimetres) of rain in both countries, with up to 15 inches (38 centimetres) in isolated areas. Heavy rainfall is of great concern to Haiti, where severe erosion in many places often leads to dangerous flooding. More than 40 people died in June following a day of heavy rain from a thunderstorm.

“The mudslide risk there is just awful,” said Phil Klotzbach, a meteorologist at Colorado State University, noting that a slow-moving storm poses great danger in Haiti given that it’s so stripped of trees.

Meanwhile, a tropical depression in the Gulf of Mexico strengthened overnight to become Tropical Storm Harold and was expected to hit the southern coast of Texas later Tuesday. It had maximum sustained winds of 45 mph (75 kph) and could strengthen further before making landfall.

A tropical storm warning is in place for the area between the mouth of the Rio Grande and Port O’Connor, meaning tropical storm conditions are expected within 12 hours. The National Hurricane Center predicted “scattered instances of flash flooding” on land and “life-threatening surf and rip-current conditions” at the coast.

Several Haitians in the capital, Port-au-Prince, told the Associated Press that they didn’t know a tropical storm was coming, despite authorities posting warnings on social media.

Marie Christine Bonjour, 39, who sells used clothes, said she didn’t have any preparations in place.

“God is the only plan. He’ll look over me and my kids,” she said. “There is nothing I can do.”

The storm approached as more than 200,000 people in Haiti are displaced, having to stay with family or in makeshift shelters because warring gangs pillaged and set fire to their homes.

“I hope God will direct the storm in another direction,” said street vendor Anne Jean-Pierre, 45. “We can’t take any more.”

Jean-Pierre, who has moved twice already because of gang violence, said she would put her essential documents in a plastic bag because she lives in an area that floods easily.

A tropical storm warning was in effect for the entire southern coast of the Dominican Republic and Haiti. A tropical storm watch was posted for the Turks and Caicos Islands.

On Aug. 10, the National Ocean and Atmospheric Administration updated its forecast and warned that this year’s hurricane season would be above normal.

Between 14 to 21 named storms are forecast. Of those, six to 11 could become hurricanes, with two to five of them possibly becoming major hurricanes, the NOAA said.

The Atlantic hurricane season runs from June 1 to November 30.