September weather forecastBiak, Indonesia

Weather in September

September brings the least rainfall of the year, dropping down to 135mm (5.31"), which is notably lower than in August. This decrease in rainfall creates a drier environment, though it does not significantly alter the tropical nature of the climate. A slight decrease in humidity is observed, but the general weather elements remain similar to the preceding months. The sunlight hours extend to nearly nine hours per day, suffusing the city with a luminous tropical vibe. The constant sea temperature and increasing number of sunny days offer an appealing scenario for water-focused activities.

Temperature

Biak registers an average high-temperature of a still moderately hot 29.2°C (84.6°F) with the arrival of September, showing minor deviation from the preceding month. Biak maintains an average low-temperature of 25.5°C (77.9°F) throughout September's nights.

Heat index

September's average heat index is estimated at a fiery hot 35°C (95°F). Ensure heightened precautions, risk of heat cramps and heat exhaustion is significant. Sustained activity could provoke heatstroke.
Heat index determinations are made taking into account the shade and light air movements. Heat index values have the potential to be boosted by 15 Fahrenheit (8 Celsius) degrees due to direct sunlight.
Note: The heat index, also known as 'real feel' or 'apparent temperature', is what the temperature feels like to the human body when the air temperature is combined with the relative humidity. The impact of weather is individual, with diverse individuals experiencing it differently due to variations in body mass, height, and activity levels. Consider the fact that direct sun exposure can influence how hot one feels, potentially raising the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for children. Kids often lack the knowledge about the necessity to take breaks and consume liquids. Thirst, as a late symptom of dehydration, necessitates the maintenance of hydration, particularly during enduring physical activities.
To prevent overheating and help regulate its internal temperature, the human body sweat and rely on the evaporation to cool down. Under conditions of high relative humidity, the rate of evaporation decreases. This results in the body retaining more heat than under conditions of dry air. Inadequate heat shedding in the face of rising body temperatures hints at potential dehydration risks.

Humidity

In Biak, the average relative humidity in September is 78%.

Rainfall

In Biak, Indonesia, during September, the rain falls for 25.8 days and regularly aggregates up to 135mm (5.31") of precipitation. In Biak, during the entire year, the rain falls for 323.4 days and collects up to 2132mm (83.94") of precipitation.

Sea temperature

The months with the coldest seawater are January through October and December, with an average sea temperature of 29°C (84.2°F).
Note: For any water activity, surface water temperatures between 25°C (77°F) and 29°C (84.2°F) are considered as excellent and extremely pleasant for lengthened periods.

Daylight

In Biak, the average length of the day in September is 12h and 7min.
On the first day of the month, sunrise is at 05:53 and sunset at 17:58. On the last day of September, sunrise is at 05:42 and sunset at 17:49 WIT.

Sunshine

In September, the average sunshine is 8.2h.

UV index

The months with the highest UV index are January, March through November, with an average maximum UV index of 7. A UV Index reading of 6 to 7 represents a high health risk from unsafe exposure to UV radiation for the average person.
Note: The daily high UV index of 7 during September translates into the following recommendations:
Stick with precautions and abide by sun safety procedures. Evading sunburn is essential. Try to minimize direct Sun exposure between 10 a.m. and 4 p.m., the peak period for UV radiation. Also note that objects like parasols or canopies might not provide complete sun protection. Limit sun-induced ocular harm with sunglasses that feature UVA and UVB filtration. Beware! Reflecting off water and sand, UV rays are much stronger.