To avoid adding more cars to its gridlocked city streets, the municipal government of Haikou, in southern China’s Hainan province, issued an urgent notice Wednesday night asking local companies to allow workers to stay home Thursday.

Due to severe fog over the Qiongzhou Strait, the water that divides the holiday island from the mainland, all three of Haikou’s ports have seen their ferry services suspended from time to time over the past week. As a result, some 10,000 cars and many more homebound travelers had still not been able to make the 35-kilometer crossing by Wednesday night.

“In Hainan, you see cars from all around China — many people choose to drive here because they come with a big family and need to carry a lot of stuff,” said Li Xingguo, 62, who is still vacationing in Hainan after arriving two weeks ago. “Traffic jams happen around this time almost every year.”

Since 2010, when Hainan’s tourism industry began taking off, the number of private cars arriving at the island during Spring Festival has increased by more than 15 percent every year, according to Party newspaper People’s Daily. This year, some 90,000 cars are estimated to have made their way to Hainan, which enjoys balmy weather even in winter.

Such thick fog has not been seen during Spring Festival since 1951, according to the Haikou government.

Flight tickets out of Hainan have surged in price as tourists struggle to return home by Thursday, the first working day after the weeklong Chinese New Year break. Flights from Sanya, a city in Hainan, to Harbin, in northeastern China’s Heilongjiang province, currently cost nearly 20,000 yuan (about $3,150) and do not return to their usual level of around 3,000 yuan until next Wednesday. Flights to other major cities also cost multiples of what they commonly go for, or are fully booked for days.

John Hu, a transportation analyst at Shenzhen-based Morningstar Investment Services, said he believes the Civil Aviation Administration is trying to adhere to the principle of market-determined pricing. In December, the authority loosened price limits on popular routes, though Hu added that he was unsure whether that policy change was having an effect.

“Now that the Civil Aviation Administration hasn’t made any comments, I personally believe the message is that they insist that the aviation companies have autonomy over the pricing,” Hu told Sixth Tone. The current extreme weather could serve as a wake-up call, he concluded, suggesting that the authority make contingency plans for similar situations in future.

Li, the vacationer, drove to Hainan with his wife a week ahead of the Spring Festival from his hometown in eastern China’s Zhejiang province. Although he originally planned to leave right after the holiday, the jam at all the three ports made the retired couple reconsider. “We’ve decided to stay another week or two,” Li told Sixth Tone.

Editor: Kevin Schoenmakers.

(Header image: A traffic jam is seen in Haikou, Hainan province, Feb. 21, 2018. Song Guoqiang/VCG)