Like most countries of Southeast Asia in the coral triangle, the island of Bali has a tropical, warm and humid climate all year round due to its close location to the Equator. With an average air temperature of 26°C, the weather in Bali is enjoyable all year round. It is important to note that the Indonesian island has two main seasons: the rainy season from November to April, and the dry season from May to October.
So far, I went diving in Bali during two very different periods of the year, the first time during the rainy season in January and the second time at the end of the dry season in October. It has taught me you can really travel anytime during the year to Bali, but it has some pros and cons you need to weigh in, especially if you want to be sure to go during the mola-mola season (oceanic sunfish).
Diving in Bali at a glance
How good diving in Bali is?
General recommendation about the best time to visit Bali
The air temperature is usually between 29°C and 31°C during the day, while it drops to 23°C at night. While Bali climate is tropical, it is essential to note that it is a volcanic island with a maximum altitude of 3,031 m; hence, the temperature decreases with the altitude. When I visited Ulun Danu Beratan Temple, which is at 1,459 m of altitude, the temperature during the day was below 20°C.
If you want to avoid the crowds, crazy traffic and higher prices on accommodation, try not to travel to Bali in July, August, Easter, Christmas, Chinese New Year and Golden Week holidays. Prices on accommodation can be 50% cheaper and the traffic on the roads more manageable outside these periods.
What you need to know about the Mola-Mola season
Something you’ll want to take into account as a passionate diver visiting Bali is mola-mola season which is from July to October. You may see elsewhere that this season is from June to November, but avoid the shoulder months if you want to increase your odds of meeting one. For a first scuba diving trip to Bali, September would be the best choice you could make to have a chance to meet Mola-Mola in Nusa Penida.
In the summer, the sea temperature decreases, due to an upwelling phenomenon that brings cold nutrient-rich waters from the depths to the surface. What happens next is the phytoplankton blooms as the dry season starts and sun exposure increases. Oceanic sunfish usually live in great depths (down to 600 m below the surface) and prefer cooler waters. This is why during the summer months, they come closer to the surface to feed on the plankton, offering scuba divers the unique opportunity to see them.
Average diving conditions in Bali
You can expect Bali water temperature to be between 27°C (July) and 30°C (January) but note the temperature can drop with depth and currents. For instance, in Crystal Bay, where the mola-molas can be seen it is usually advised to wear at least a 5mm wetsuit as the temperatures are generally between 23 and 25°C at 30 m. On the other hand, water temperatures in Menjangan Island are usually warmer than Bali’s average.
In Bali, the visibility varies with the amount of rainfall; it can drop to 10 m (*) in the rainy season, and can reach 40 m (*****) in the heart of the dry season.
Diving Bali in January
Most of January is considered low season as in the middle of Bali’s rainy season.
Conditions:
- Average water temperature at the surface: 29°C
- Air temperature: min 26°C – max 30°C
- Average days of rain: 18
- Visibility *
Peak season:
Chinese New Year is a peak tourist season due to holidays of people from China, the exact dates change every year between January and February.
Feedback from my experience:
While January is in the middle of the rainy season in Bali, this is the month I chose for my first trip there. It mainly was raining at night and maybe an hour or two during the day. I enjoyed sunny weather most days and lower rates on accommodation (10€ for a private bungalow in Amed for example). The main drawback was the rain did affect the visibility underwater. The water temperature was warm, between 28 and 29°C.
Diving Bali in February
Most of February is considered low season as in the middle of Bali’s rainy season.
Conditions:
- Average water temperature at the surface: 29°C
- Air temperature: min 26°C – max 30°C
- Average days of rain: 17
- Visibility *
Peak season:
Chinese New Year is a peak tourist season due to holidays of people from China; the exact dates change every year between January and February.
Diving Bali in March
Most of March is considered low season as in the middle of Bali’s rainy season.
Be aware of Balinese new year called “Nyepi” is a full 24-hour period where silence and inactivity must be observed, visitors must stay at their hotel the whole day and can’t engage in any activity. It is usually at the end of the month, check the exact date.
Conditions:
- Average water temperature at the surface: 29°C
- Air temperature: min 26°C – max 31°C
- Average days of rain: 15
- Visibility *
Peak season:
Easter is a peak tourist season due to the holidays of people from Europe and Australia; the exact dates change every year between March and April.
Diving Bali in April
Most of April is considered low season, this is the last month of Bali’s rainy season.
Conditions:
- Average water temperature at the surface: 29°C
- Air temperature: min 26°C – max 31°C
- Average days of rain: 11
- Visibility **
Peak season:
Easter is a peak tourist season due to the holidays of people from Europe and Australia; the exact dates change every year between March and April.
Last week of April is a peak tourist season due to Golden week holidays for people from Japan.
Diving Bali in May
Most of May is considered shoulder season and it is the first month of Bali’s dry season.
Conditions:
- Average water temperature at the surface: 29°C
- Air temperature: min 26°C – max 30°C
- Average days of rain: 9
- Visibility ***
Peak season:
First week of May is a peak tourist season due to Golden week holidays for people from Japan.
Diving Bali in June
June is shoulder season and in the middle of Bali’s dry season.
Conditions:
- Average water temperature at the surface: 28°C
- Air temperature: min 25°C – max 29°C
- Average days of rain: 7
- Visibility ***
Diving Bali in July
July is peak tourist season and in the middle of Bali’s dry season. This is also the start of the mola-mola season (oceanic sunfish) at Crystal Bay between Nusa Ceningan and Nusa Penida.
Conditions:
- Average water temperature at the surface: 27°C
- Air temperature: min 24°C – max 28°C
- Average days of rain: 5
- Visibility ****
Peak season:
July is a peak tourist season due to summer holidays for people from Europe.
Diving Bali in August
August is the peak tourist season and in the middle of Bali’s dry season. August is in the heart of the mola-mola season (oceanic sunfish) at Crystal Bay between Nusa Ceningan and Nusa Penida.
Conditions:
- Average water temperature at the surface: 27°C
- Air temperature: min 24°C – max 28°C
- Average days of rain: 4
- Visibility *****
Peak season:
August is a peak tourist season due to summer holidays for people from Europe.
Diving Bali in September
September is shoulder season and in the middle of Bali’s dry season. This month is still in the heart of the mola-mola season (oceanic sunfish) at Crystal Bay between Nusa Ceningan and Nusa Penida.
Conditions:
- Average water temperature at the surface: 27°C
- Air temperature: min 24°C – max 29°C
- Average days of rain: 5
- Visibility ****
Diving Bali in October
October is shoulder season and is the last month of Bali’s dry season. This is when the mola-mola season (oceanic sunfish) ends at Crystal Bay between Nusa Ceningan and Nusa Penida.
Conditions:
- Average water temperature at the surface: 28°C
- Air temperature: min 25°C – max 30°C
- Average days of rain: 8
- Visibility ***
Feedback from my experience:
For my second trip to Bali, I planned according to the mola-mola season. The weather was hot and sunny with temperatures above 30°C most days. However, mid-October was a bit late to see the mola-molas. Luckily, I saw one on my first dive in Crystal Bay. At Manta Point, it was like a manta ray highway; it is not always like this, but you are almost sure to see them at this time of the year. The water temperature is cooler in Nusa Penida, between 23 and 25°C, whereas in Bali, it was around 30 in Tulamben and even 32°C in Menjangan.
Diving Bali in November
November is low season and in the first month of Bali’s rainy season.
Conditions:
- Average water temperature at the surface: 29°C
- Air temperature: min 26°C – max 31°C
- Average days of rain: 12
- Visibility **
Diving Bali in December
Most of December is low season and is in the middle of Bali’s rainy season.
Conditions:
- Average water temperature at the surface: 29°C
- Air temperature: min 26°C – max 30°C
- Average days of rain: 14
- Visibility *
Peak season:
The end of December with Christmas and New Year’s Eve is a peak tourist season due to the holidays of people from Europe and Australia.
Do you need more information to plan your dive trip to Bali? Check these additional articles about travelling and scuba diving in Bali:
If you enjoyed this post, subscribe to WAD Newsletter to receive the latest posts directly into your inbox.