Cat Ba Weather in September
September in Cat Ba typically sees daytime highs of 31°C (88°F) and nighttime lows of 27°C (81°F). September falls within the rainy season, so heavy rainfall is to be expected.
Rainfall in Cat Ba in September
As part of the rainy season, Cat Ba sees around 14 days of rain in September, with an average of 330 mm (13 in). Showers during the rainy season tend to be heavy and can come down intensely. An umbrella is often not enough, so a poncho or waterproof jacket is a better choice.
Temperature in Cat Ba in September
In September, Cat Ba gets very high temperatures, with highs of 31°C (88°F). Nights cool to around 27°C (81°F). Mornings and evenings are often more comfortable than the peak afternoon hours. With overnight lows of 27°C (81°F), nights stay very warm. Air conditioning makes a real difference if you're sensitive to heat. A cold shower before bed can also help you get to sleep more comfortably.
Sunshine in Cat Ba in September
There are approximately 190 hours of sunshine this month, despite being the rainy season. Rain often arrives in the late afternoon or evening, keeping mornings and early afternoons sunny. Even during the wet season, it could still be a nice time to visit.September in Cat Ba can still be great, but if you prefer pleasant temperatures along with dry and sunny conditions, our weather planner can help you explore other options in the world.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Vietnam, check out our Cat Ba's climate page.
Cat Ba Temperature in September
Min Temperature
27°C (81°F)
Max Temperature
31°C (88°F)
Chance of Rain
47%
Precipitation
330 mm (13 in)
Rainy days
14 days
Humidity
83% *
Sunshine
190 hours *
Percentage Sunshine
*
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Cat Ba typically stay consistent throughout September, with daily highs averaging around 31°C (88°F). Nights are warm, with lows around 25°C (77°F).
Average temperatures in September
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in September
Historical weather for Cat Ba in September
Browse day-by-day weather records for Cat Ba spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Cat Ba historical weather extremes in September
Based on weather observations in Cat Ba between 1976 and 2025, these are the recorded extremes during September.
- The hottest September day on record in Cat Ba reached 37°C (99°F) (September 5, 2024).
- On September 27, 1997, Cat Ba saw its coldest September day with temperatures maxing out at 19°C (66°F).
- Cat Ba registered its coldest September night on September 27, 1997, with temperatures dropping to 16°C (61°F).
Best Places in Vietnam in September
Find out more about the weather in Vietnam and which places have the best travel conditions in this month. See all of Vietnam in September →
perfect weather
pleasant
tolerable
unpleasant
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What to Wear in Cat Ba in September
Warm weather calls for comfortable, breathable clothing in September. Cotton t-shirts, shorts, light dresses, and sandals are perfect. You might still want a light layer for evenings or air-conditioned places (for example buses). Also bring a poncho, it will rain a lot! Waterproof everything you can. Don't forget sun protection, sunglasses, sunscreen, and a hat. These are all good ideas with this much sunshine.What To Do in Cat Ba in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Vietnam, check out our Cat Ba's climate page.
Temperature Rainfall Sunshine Humidity
See the full Cat Ba climate overview or explore weather in Vietnam.
