Canadian airlines are sending planes to the Dominican Republic as well as Turks and Caicos to bring people back to Canada ahead of Hurricane Irma.

The first Air Transat and WestJet planes left Toronto's Pearson and Montreal's Trudeau airports by 7 a.m. ET, and were all slated to return by 7 p.m. ET, while Air Canada says it is taking steps to help customers.

Neither Air Transat nor WestJet specified precisely how many passengers are expected to return to Canada.

Montreal-based Air Transat said it is sending aircraft to the Dominican Republic — seven to Punta Cana, two to Puerto Plata and one to Samana. 

"All aircraft should arrive in the Dominican Republic on the morning of September 6th, and passengers should be back in Canada in the afternoon or early evening," the airline said in a news release.

Calgary-based WestJet said it has "a number" of 737-800s operating as rescue flights to Punta Cana and Puerto Plata on Wednesday. For Thursday, the airline plans to run additional flights to Santa Clara and Cayo Coco in Cuba to return travellers to Canada.

Earlier, Westjet had said it was sending five planes to the Caribbean: three to Punta Cana, another to Puerto Plata, and one aircraft to Turks and Caicos.

Air Canada, headquartered in Montreal, said it is "monitoring the situation closely and taking steps to assist our customers, including proactively contacting them on location to inform them on increased capacity and additional flights." 

Irma, considered the most powerful Atlantic Ocean hurricane in recorded history, made landfall in the northeast Caribbean overnight. The storm is following a path predicted to then rake Puerto Rico, the Dominican Republic, Haiti and Cuba before possibly heading for Florida.

The Category 5 storm had maximum sustained winds of 295 km/h, according to the U.S. National Hurricane Center in Miami.

On Tuesday, Air Canada added extra flights to Antigua and Providenciales in the Turks and Caicos island chain. 

The airline added extra flights to the Dominican Republic on Wednesday and is replacing some routes to Cuba and Florida with larger aircraft to accommodate those wishing to travel early, said Isabelle Arthur, senior manager of media relations with the airline. 

The airline has also waived fees for customers wanting to change flights.

American Airlines has added extra flights out of the Caribbean islands of St. Maarten and St. Kitts and Nevis, and is also allowing people booked on flights in Irma's path to rebook with no change and under certain guidelines. 

Sunwing said southbound flights departing Wednesday and Thursday to Punta Cana, and Wednesday through Friday to Puerto Plata have been cancelled, but customers have been given the option to rebook or change destination. The company said passengers due to depart to Cuba between Wednesday and Sunday can also rebook or change destination. 

Sunwing also said northbound service from Punta Cana and Puerto Plata is scheduled to depart as normal on Wednesday, "in addition to special flights arranged to bring passengers currently in destination home early." The company did not specify the number of special flights.

Toronto resident Adrianna Prosser, however, said she has had no success in getting hold of anyone with Sunwing. Prosser arrived in Punta Cana  on Monday, and said the phone lines are dead and company representatives on the island can't be found.

"There are no flights," she told CBC News. "There are a lot of cancellations and people are making the best of it."

"Right now, the trajectory [of the storm] has swooped up a little bit north, so we're hoping that we just get the tropical storm rather than the hurricane."

Bahamas Prime Minister Hubert Minnis said his government was evacuating the six islands in the south because authorities would not be able to help anyone caught in the "potentially catastrophic" storm.

People there would be flown to Nassau starting Wednesday in what he called the largest storm evacuation in the country's history.

Hurricane Irma Dominican Republic

Members of the country's civil defence force prepare their gear ahead of Hurricane Irma, in Santo Domingo, Dominican Republic. (Ricardo Rojas/Reuters)

With files from The Canadian Press