Rainwater from Cyclone Gonu floods Al-Khoud Street in Muscat, the capital of Oman, on Wednesday afternoon. Oman evacuated tens of thousands of people Wednesday, suspended oil exports and closed the major port of Sohar as the cyclone roared toward the Strait of Hormuz, the world's major transport artery for Persian Gulf oil.

Muscat, Oman ? Cyclone Gonu battered Oman’s coast Wednesday with fierce winds and torrential rains, forcing thousands from their homes and shutting down oil installations before heading toward the world’s most important crude oil tanker route.

The storm – a rarity in the Middle East – weakened slightly and dropped below hurricane strength late Wednesday, according to the U.S. military’s Joint Typhoon Warning Center.

It was expected to make landfall on the southeastern Iranian coast late tonight, but it was likely to spare Iran’s offshore oil installations that lie more than 120 miles to the west, the center and oil officials said.

In Muscat, the cyclone unleashed sheets of rainfall and howling winds rarely seen in the quiet seaside capital. Police and emergency vehicles could hardly move through the flooded streets, and authorities used text messages to warn people away from low-lying areas.

The storm caused little damage to Oman’s relatively small oil fields. But raging seas prevented tankers from sailing from Omani ports, effectively shutting down the country’s oil exports, said Nasser bin Khamis al-Jashimi of the Ministry of Oil and Gas.

Authorities also closed all operations at the port of Sohar and evacuated 11,000 workers, port spokesman Dirk Jan De Vink said.

To the north, the port of Fujairah in the United Arab Emirates suspended all refueling and ship-to-ship supply operations the world’s third-largest shipping fuel center. Ships were allowed to berth but other activities were halted, causing a delay in loading oil tankers, officials said.

A few ships were sailing through the nearby Strait of Hormuz despite 4- to 6-foot swells and strong winds, according to Suresh Nair of the Gulf Agency Co. shipping firm. About one-fifth of the world’s oil passes through the narrow waterway at the entrance to the Persian Gulf.

“About 17-21 million barrels a day of oil are coming out of the Persian Gulf. Even if only some of the tankers are delayed, that could reduce the supply of oil and increase prices,” said Manouchehr Takin, an analyst at the Center for Global Energy Studies in London.

But Tim Evans, an analyst at Citigroup Global Markets, said the storm shouldn’t have a major impact on prices because while it may delay oil shipments, they will eventually get to their destinations. Oil prices rose 25 cents to $65.86 a barrel in midday trading on the New York Mercantile Exchange after initially falling.