Cat Ba Archipelago consists of 367 islands, including Cat Ba Island. This island is located in the south of Halong Bay, off the coast of Haiphong City and Quang Ninh province, about 30 km from Haiphong City, and about 25 km from Halong City. In terms of administration, the archipelago belongs to Cat Ba District (Haiphong City). Cat Ba Island is recognized as the world biosphere reserve by UNESCO. Infrastructure in Cat Ba Island is well developed with complex of hotels, motels, resorts, and temples, and especially the whole island area was equipped with wireless base stations. Weather in Cat Ba Island is influenced by both weather in Northeast Vietnam and weather in Red River Delta.
Cat Ba is a beautiful and romantic island, located at average latitude of 70 m above the sea level (in the range of 0-331 m). Cat Ba weather is specified by the tropical monsoon climate and influenced by the ocean. Thus, the averages of temperature, humidity, and precipitation in Cat Ba Island are equivalent to areas nearby. However, it is characterized with less cold in winter and cooler in summers than that of mainland area. To specify, the average temperature is from 25-28°C ranging according to seasons. In summer, the figure can reach 30°C, while in winter, it is about 15-20°C, even 10°C sometimes with the operation of north-east monsoon. The average precipitation in Cat Ba is about 1700-1800mm per year, which fluctuates according to seasons. Rainy season runs from July to August. The tidal fluctuation is from 3.3m to 3.9m. The salinity is from 0.930% in wet season to 3.111% in dry season.
Climate in Cat Ba Island is neither too hot nor too cold. Here, the average temperature is 23-24°C with two distinct seasons: dry season and rainy season. Cat Ba Island is the main island in the Cat Ba Archipelago with various terrain, cool climate, quite diverse and rich natural resources on the island. Notably, Cat Ba National Park was recognized as the World Biosphere Reserve by UNESCO in 2003. And, this is the third world biosphere reserve in Vietnam after Can Gio National Park and Cat Tien National Park. Mangrove coastal areas in the island are the habitats of unique species of aquatic plants and animals, especially waterfowl and migratory seasonal birds. The attraction of Cat Ba National Park represents through constituents in topography and geology with lakes in limestone, unique caves and beautiful coral reefs along the foot of small islands in Lan Ha Bay.
The best time to travel Cat Ba Island is from late September to November. During this time, weather in Cat Ba is portrayed by mild temperature and azure sky. These months are really an ideal period to enjoying wonderful time on the beach and contemplating stunning scenery of this island. Cat Ba Island weather in December is described by cold and dry air. In March and April, the temperature is higher, and rains occur, causing high humidity. Traveling Cat Ba at any time during a year, tourists will be lured into beautiful beaches, amazing caves, and fresh seafood. In addition, taking part in games and activities on the beach is an indispensable things to do in Cat Ba Island.
Cat Ba Island as well as many tourist attractions in Northern Vietnam will be very appropriate if you travel in summer to feel the cool breeze of the sea, enjoy beautiful sunlight, and turquoise waters. However, at the beginning of autumn, Cat Ba Island is also very beautiful and romantic. Come to Cat Ba Island in autumn, tourists can enjoy blue and cool seawater without being interfered by the crowd like in summer. You will have serene moments to look at each change of natural landscapes here.