Climate Insights for Cát Bà

The climate in Cát Bà is warm and mild. The average annual temperature is 24°C and approximately 1971mm of precipitation falls per year. August is the wettest month, receiving around 573mm of rainfall. 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 February, January, March, when temperatures can drop to 15°C.

Cát Bà sees moderate temperature variation throughout the year, ranging from 15°C to 31°C. The warmest month is June, when average highs reach 31°C and the mean temperature sits around 30°C. February is the coolest month, with minimum temperatures around 15°C and an average of 16°C. Daily temperature variation is modest, with an average difference of 2°C between highs and lows. The sharpest temperature change occurs between March and April, with a 4°C shift in average temperatures.

Cát Bà is a fairly wet location, receiving approximately 1971mm of precipitation annually, which averages out to around 164mm per month. The wettest month is August, averaging 573mm of rainfall. September and July also tend to see above-average precipitation. The driest month is December, with just 10mm. That's 562mm 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 relatively calm, with an average annual wind speed of 5km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is July, averaging 6km/h, though still comfortable for most outdoor activities. The calmest conditions occur in April, with average winds dropping to 4km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 2km/h gap between the calmest and windiest months.

It is currently summer in Cát Bà, which began on June 21, 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 February near 15°C. Autumn is next, beginning on September 23, 2026 — 63 days from now.

The best time to visit Cát Bà is during 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 31mm 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.