Nida is generating winds up to 150 kilometers per hour (93 miles per hour) as it moves northwest towards southwest China.
"When it finally makes it there, it will slow down and weaken," CNN meteorologist Allison Chinchar said. "The weakening part is the good news. The slowing down is not the good news because that will allow for some training so the rain will end up going over and the same spots as the waves come in."
According to Hong Kong International Airport
's website, 181 flights scheduled to depart or arrive Hong Kong between Monday and Tuesday have been canceled.
All Cathay Pacific Airways and Dragonair flights scheduled to go through Hong Kong between 10 p.m. local time on Monday until 2 p.m. the next day will be suspended, the airlines said in a press statement.
A spokesman for Hong Kong's Airport Authority said the public should check its website and with their airline before departure for the latest flight information.
The Hong Kong Observatory issued a Tropical Cyclone Signal 3
Monday at midday, closing all kindergarten schools and special needs classes. It will raise the signal to a level eight later in the evening.
"The weather will deteriorate rapidly after sunset. There will be squalls, heavy rain and rough seas. There may be flooding in low-lying areas," the Observatory said.
Nida is expected to arrive during high tide increasing the threat of flooding, it noted.
China's National Meteorological Center also issued an orange alert warning for gales and torrential rain in its southern provinces. It is the second-highest level on the country's four-tier weather warning system.
People in affected areas have been instructed to stock up on daily necessities to last one to three days, the China National Commission for Disaster Reduction said, according to Xinhua.
Nida, also called Tropical Storm Carina, hit the Philippines on Saturday pouring up to 287 millimeters (11 inches) of rain over the country's northern parts.
Northern Luzon and the provinces of Zambales and Bataan are still on alert for flash floods and landslides triggered by the rains, the Philippines Atmospheric Geophysical and Astronomical Services Administration (PAGASA) said.
Government agencies are also on standby to provide aid, CNN Philippines reported
, with over 31,000 family food packs prepared.