It lashed the city with unprecedented strength resulting in destructive winds and floods with 115 miles per hour wind speed making Mekunu the strongest storm to ever hit the country.
Underpasses have been flooded as the cyclone drenched the city in water. The Arabian Sea churned Saturday morning, sending mounds of sea foam into the air.
The search is ongoing for eight Indian sailors who went missing when the cyclone hit Socotra's port.
Gulf News reported on Sunday that the death toll from Mekunu had risen to 10, with 40 others still missing.
The airport, which has been closed since Thursday, will reopen early on Sunday, Oman's civil aviation authority said.
In a statement, the authority said the airport would close at midnight Thursday for a 24-hour period, which, it said, could be extended further depending on climatic developments.
Seventeen people are now missing on Socotra Island in the Arabian Sea, where the cyclone has already hit.
People visit a road which has been cut by the flood water after Cyclone Merkunu in Salalah Oman Saturday
Flash floods engulfed Socotra's streets, cutting electricity and communication lines.
The Port of Salalah, a key gateway for the country, is also closed with its cranes secured against the pounding rain.
Civil defence officials said a man and a 12-year-old girl were killed, while three Asian nations were missing after the cyclone hit Oman's Dhofar and AlWusta provinces.
Meanwhile, Yemen's government has declared the island of Socotra a disaster zone.
The entire country of Oman is in grave danger as Tropical Cyclone Mekunu travels over the Arabian sea.
Socotra has a unique ecosystem and is home to plants, snails and reptiles that can be found nowhere else.
In 2007, Cyclone Gonu tore through Oman and later even reached Iran, causing $4 billion in damage in Oman alone and killing over 70 people across the Mideast.
"Latest observations show that tropical Cyclone Mekunu has intensified to Category 2", with high wind speeds, Oman's Directorate General of Meteorology said on Twitter.
Moon, Kim discuss scrapped summit as Donald Trump signals optimism
At that meeting, they declared they would work towards a nuclear-free Korean peninsula and a formal end to the 1950-53 Korean War. He said, if the summit does happen it will likely remain in Singapore and be on that same June 12 date.