The worst storm of the season so far was on track to hit Hong Kong as Typhoon Nida barreled Monday toward south China. The Hong Kong Observatory, a government weather agency, issued a No. 8 storm signal late Monday as schools suspended classes and airports canceled more than 120 flights. No. 8 signals indicate that gales or storm-force winds are expected with sustained speeds up to 72 mph and gusts up to 112 mph.

As of 11 p.m. local time, Typhoon Nida was about 106 miles east-southeast of Hong Kong, moving west-northwest at about 16 mph, according to the observatory. It was on schedule to make landfall Tuesday.

"People should be aware that the weather will deteriorate rapidly after sunset. There will be squalls, heavy rain, rough seas and the possibility of flooding in low-lying areas,” observatory scientist Shum Chi-tai told the South China Morning Post. "If Nida hits Hong Kong directly or skirts just to the south of the territory, the impact on us will be even more serious, especially if the storm surge coincides with the high tide on Tuesday morning."

AccuWeather compared Typhoon Nida to a Category 2 hurricane. It's the fourth typhoon in China in 2016, Reuters reported.

The storm just came through the Philippines, where it was called Typhoon Carina. The system displaced nearly 9,000 people in two provinces, flooded rivers with 10 inches of rain and caused power outages over the weekend, the Manila Times reported.

Certain cities in China were already preparing for Typhoon Nida Monday, with Guangzhou shutting down schools and factories and gathering its emergency response teams. Shenzen suspended sea and shore operations and encouraged fishermen to dock their boats, according to Xinhua.

The storm will "rapidly weaken" once making landfall, AccuWeather meteorologist Adam Douty said. But it will continue to pose a serious rain threat through Thursday.

Check out social media photos of locals getting ready for and reacting to Typhoon Nida below: