Southwest Haiti and portions of Jamaica were bracing for "catastrophic" flash flooding and landslides from the intense and fast-developing hurricane, which has already killed at least four people.

Evan Thompson, director of Jamaica's Meteorological Service, said hurricane conditions would be felt in Jamaica starting Monday, and the storm is expected to move across the country Tuesday. Strong winds were already being felt.

"There is a slight shift in the track, moving it a little west than where it was originally projected," he said. "We earlier had said that it would make impact or landfall along the coast of Clarendon, but it seems now to be shifted more to Manchester."

Both are parishes on Jamaica's southern coast, with Manchester about 25 miles west of Clarendon. The island's parishes are divided among three counties.

Meteorologists said the projections of up to 35 inches of rain were "unprecedented."

"We are expecting that a lot of rainfall will continue to be dousing the island," Thompson added.

In Cuba, which struggles to keep electricity running even in dry weather conditions, authorities were cleaning streets to prevent clogged drains and flying debris, trimming trees, and taking down traffic lights as coastal communities were ordered evacuated. Six provinces were under a hurricane watch.

In the Dominican Republic, nearly 4,000 people had been evacuated by midday Sunday, and four southern provinces were on red alert, said General Juan Manuel Méndez, the director of the country's Emergency Operations Center.

Some bridges and homes had been damaged by rain days before the storm's official arrival, he said.

Méndez urged citizens to be mindful of the enormous amounts of rain that could cause landslides. He urged people to heed warnings and stay indoors and announced his cell phone number if anyone needed to be evacuated if they were caught in landslides.

"We can't post a soldier in every city for people to stay in their homes," he said.

A teenager who had been swimming in the sea near Santo Domingo was missing, and another man was swept away by a river, Dominican authorities said.

In Haiti, authorities acknowledged that they were unable to reach some communities that are under gang control.

About 2,000 people were in shelters across southern Haiti. Three people there had died, and 15 more were injured, authorities said. A mudslide in Fontamara killed two of the three and the third, a 70-year-old man, died when he was struck by a falling tree in Marigot in the south near Jacmel, according to Haiti's civil defense agency.

In Praville, a hamlet in the northern Haitian city of Gonaïves, a wall collapsed under the force of runoff water, injuring 15 people, civil defense authorities said.

In Les Cayes, a city in southern Haiti, the main cemetery and a public school were flooded. People who had to evacuate after flooding in September were forced to leave their houses again.

Jenel Loubeau, a 28-year-old soccer coach in Les Cayes, said his house had taken in about 1 foot of water.

"I left and took all my important papers, because the flood was so bad, I was worried the whole house would fall," he said. "The inside of the house was full of water. Everything is wet, my passport, documents, and my food and other things."

The United Nations World Food Program said it started sending emergency cash to Haitian communities in anticipation of the storm. About 45,000 people received a total of $900,000.

In the Dominican Republic, 4,000 families received cash assistance from the program, while the organization positioned food in eastern Cuba to feed 275,000 people for up to 60 days.

More relief items were being shipped to Barbados to send them to Jamaica if needed, the agency said.

In Jamaica, disaster management committees have been activated and are ready, and residents appear to be taking the storm seriously and beginning to panic, said Norman Scott, the mayor of Spanish Town, just west of the capital, Kingston.