Climate Insights for Cát Bà

The climate in Cát Bà is warm and mild. The average annual temperature is 25°C and approximately 1987mm of precipitation falls per year. Cát Bà receives a notable amount of rainfall throughout the year, including during its driest month. Cát Bà is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: June, July, August. The coldest months are January, February, December, when temperatures can drop to 17°C.

Cát Bà sees moderate temperature variation throughout the year, ranging from 17°C to 31°C. The warmest month is June, when average highs reach 31°C and the mean temperature sits around 30°C. January is the coolest month, with minimum temperatures around 17°C and an average of 18°C. Daily temperature variation is modest, with an average difference of 3°C between highs and lows. The sharpest temperature change occurs between November and December, with a 4°C shift in average temperatures.

Cát Bà is a fairly wet location, receiving approximately 1987mm of precipitation annually, which averages out to around 166mm per month. The wettest month is August, averaging 477mm of rainfall. September and July also tend to see above-average precipitation. The driest month is February, with just 30mm. That's 447mm less than August, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic.

Cát Bà is moderately windy, with an average annual wind speed of 21km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is June, averaging 24km/h, noticeable enough to affect lighter outdoor activities. The calmest conditions occur in September, with average winds dropping to 19km/h, making it an ideal period for wind-sensitive activities. Wind conditions are fairly consistent throughout the year, varying by only 5km/h between the calmest and windiest months.

It is currently spring in Cát Bà, which began on March 20, 2026. Cát Bà is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in June at around 31°C, while the coldest stretch bottoms out in January near 17°C. Summer is next, beginning on June 21, 2026 — 89 days from now.

The best time to visit Cát Bà is during January, February, March, April, November and December, when the weather is most comfortable for travellers. During these months, average temperatures hover around 21°C with modest rainfall averaging 42mm per month. By contrast, June can be uncomfortably hot with temperatures reaching 31°C. A light rain jacket is recommended, though showers are generally brief and shouldn't disrupt your plans.

The table below shows monthly climate averages for Cát Bà based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.