Gusts of wind whipped palm trees and fishermen pulled their boats in and tied them down along Mexico's Caribbean coast as rain and strong waves moved ashore in Cancun and neighboring Puerto Juarez. Tourists, meanwhile, tried to continue vacationing as usual despite the Category 1 storm.

"I figure probably in a couple hours we'll be stuck inside," said Julie Randolph, 40, a social worker from Ormand Beach, Florida, who braved the rain to jog along the near-empty beach.

Randolph said she was monitoring Ida's progress on her iPhone. "I'm always concerned about storms, but I feel comfortable and safe in my surroundings," she said. "We would have left if we felt threatened. We still can leave now."

The Cancun airport was still open and there were no plans to close it, according to airport spokesman Eduardo Rivadeneira.

As winds picked up and intermittent rains intensified Sunday morning, restaurants and nightclubs near the waterfront began covering their windows with large pieces of plywood.

Officials said the worst of the storm would likely hit Cancun around midday. They advised residents to stay inside and avoid putting their trash out on the streets.

"Right now it is very, very calm," Civil Defense director Ruben Avalos Gutierrez said. "The phenomenon is going to be very close. We will get rain and wind gusts."

Ida had winds of about 90 mph (150 kph). The storm was passing about 60 miles (100 kilometers) offshore from Cancun, and 85 miles (135 kilometers) southwest of Cuba.

It was moving northwest at about 12 mph (19 kph) on a projected path that could have it arriving at the U.S. Gulf coast around Tuesday.

Forecasters at the U.S. National Hurricane Center in Miami, Florida, said Ida could become a Category 2 hurricane late Sunday.

It is expected to interact with a weakening cold front over open seas and will most likely be a tropical storm or perhaps a low-level hurricane when it gets to the Gulf Coast, said Jack Beven, a hurricane specialist at the center.

But when that will happen isn't entirely clear, he said, which prompted officials to issue a hurricane watch for the coastline from Grand Isla, Louisiana, to the Mississippi-Alabama state line. The watch means hurricane conditions are possible within 36 hours.

Parts of the Yucatan Peninsula remained under a hurricane warning, and a tropical storm warning was in place for the western tip of Cuba with heavy rains expected.

In El Salvador, Interior Minister Humberto Centeno reported 40 dead from flooding following three days of heavy rains that may be indirectly tied to Ida.

Dave Roberts, a Navy hurricane specialist at the hurricane center, said Ida's presence in the Caribbean may have played a role in drawing the Pacific low pressure system toward El Salvador, causing those rains.

However, he said, "if there were deaths associated with this rainfall amount in El Salvador, I would not link it to Ida."

Hurricane Ida passed through neighboring Nicaragua on Thursday, damaging or destroying about 500 homes, as well as roads, bridges and public buildings.