Meteorologists warned that Mekunu was gaining strength and would be "extremely severe" when it crashes into the mainland Arabian Peninsula. Mekunu, which may be upgraded to Category 3, is expected to make landfall on Friday night.
Tourists rushed to catch the last flights out before Salalah International Airport closed at midnight Thursday for the storm, where sandbags already stacked against some doors.
Mekunu will not directly hit the UAE, but could bring thundery showers.
"The weather around 1000 kms of Cyclone Mekunu is rough and wind is very strong, we had issued an advisory to fishermen to not venture in the sea".
The officials said Friday that over 230 families had been relocated to shelter in sturdier buildings and other areas, including those more inland and in the island's mountains.
Flash floods engulfed Socotra streets, washed away thousands of animals and cut electricity and communication lines, they said.
Socrotra is now embroiled in another kind of storm, as tensions between the Yemeni government and the United Arab Emirates over the presence of Emirati troops on the island recently reached a head.
Yemen's self-exiled President Abed Rabbo Mansour Hadi in a statement ordered troops under his command on the island to help citizens, deliver supplies and reopen roads.
The officials told Associated Press that heavy rains were now pummelling Yemen's easternmost province of Al Mahra, on the border with Oman.
Yemen's pro-government SABA news agency reported that 17 people were missing after two ships capsized in the storm and three vehicles washed away.
Workers take a rest in a school turned into a shelter in Salalah Oman
The cyclone caused landslide, collapsing coastal roads in Hadibu.
Socotra has a unique ecosystem and is home to rare species of plants, land snail and reptile species that can be found nowhere else around the planet. It is known for its flower-and-fruit bearing dragon blood tree, which resembles an umbrella and gets its name from the dark red sap it secretes.
State-run television said authorities had evacuated hundreds of residents from a small island off Salalah, the town where Oman's Sultan Qaboos was born. The storm sent torrents of rain pouring through homes and streets, leaving residents soaking wet and trying to wade to safety. It also evacuated the critically ill from Sultan Qaboos Hospital in Salalah, flying them north to Muscat.
The port of Salalah, crucial to Qatar amid a boycott by four Arab nations over a diplomatic spat with Doha, said it also had taken precautions and secured cranes ahead of the cyclone.
Streets quickly emptied across the city. Standing water covered some roads and caused at least one auto to hydroplane and overturn. A sizable police presence fanned out, many in Royal Oman Police SUVs with chicken wire over the windows.
As torrential rains poured down, authorities opened up schools to shelter those whose homes are at risk. About 600 people, mostly labourers, huddled at the West Salalah School, some sleeping on mattresses on the floors of classrooms, where math and English lesson posters hung on the walls.
Shahid Kazmi, a worker from Pakistan-controlled Kashmir, said police had moved him and others to the school. He acknowledged being a bit scared of the storm but said: "Inshallah, we are safe here".
Seasonal rains are not unusual for southern Oman this time of year. While the rest of the Arabian Peninsula bakes in areas where temperatures near 50 degrees Celsius (122 degrees Fahrenheit), those in the sleepy port city of Salalah enjoy rainy weather that sees fog and cool air wrap around its lush mountainsides. Temperatures drop down around 77 degrees during its annual monsoon festival.
The death is the first confirmed in the powerful cyclone. Over a roughly 100-year period ending in 1996, only 17 recorded cyclones struck Oman.
In 2007, Cyclone Gonu tore through Oman, killing at least 49 people and causing damage estimated at $3.9 billion (3.3 billion euros).