September weather forecastDumai, Indonesia
September
Weather in September
The first month of the autumn, September, is still a tropical month in Dumai, Indonesia, with temperature in the range of an average high of 32.2°C (90°F) and an average low of 24°C (75.2°F).Temperature
The onset of September notes an average high-temperature of a still hot 32.2°C (90°F), subtly shifted from August's 32.4°C (90.3°F). An average low-temperature of 24°C (75.2°F) is common during the nights of September.Heat index
The heat index value for September is calculated to be a blazing hot 45°C (113°F). Attention: Heat exhaustion and heat cramps are anticipated. Prolonged effort can result in heatstroke.One should consider that heat index numbers are for shaded settings and light wind. Uninterrupted exposure to the sun may boost the heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'feels like', gives a temperature feeling by integrating air temperature and humidity. The perception of temperature can be subjective, varying based on activity and individual heat sensitivity, influenced by factors like wind, attire, and metabolic variations. Direct sun rays have a notable impact on perceived temperature, which can raise the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly relevant to children. Young ones regularly neglect the requirement for rest and fluid replenishment. Thirst is a late stage of dehydration - so, it is necessary to keep hydrated, particularly during extended periods of physical exertion.
The body's natural response to excessive warmth is perspiration, as it allows for cooling through sweat evaporation. In high relative humidity, the body's ability to evaporate heat is diminished, resulting in a heightened feeling of warmth. As the body accumulates more heat than it can release, body temperature goes up, increasing the risk of heat-related health issues.
Humidity
The average relative humidity in September is 79%.Rainfall
In Dumai, in September, it is raining for 24.6 days, with typically 82mm (3.23") of accumulated precipitation. Throughout the year, there are 286.4 rainfall days, and 1200mm (47.24") of precipitation is accumulated.Sea temperature
In Dumai, the average seawater temperature in September is 29.4°C (84.9°F).Note: Between the temperatures of 25°C (77°F) and 29°C (84.2°F), water is considered very warm, providing pleasure in water activities without discomfort over lengthy periods.
Daylight
The average length of the day in September is 12h and 7min.On the first day of September, sunrise is at 06:09 and sunset at 18:18. On the last day of the month, sunrise is at 06:01 and sunset at 18:07 WIB.
Sunshine
In Dumai, the average sunshine in September is 8.5h.UV index
The months with the highest UV index are January through September and November, with an average maximum UV index of 7. A UV Index of 6 to 7 symbolizes a high threat to health from unsafe exposure to UV radiation for the ordinary person.Note: The maximum UV index of 7 during September translates into these guidelines:
Apply measures and align with sun safety principles. Safeguarding against skin and eye injury is pivotal. Avoid direct Sun exposure and stay in the shade between 10 a.m. and 4 p.m., a time when UV radiation is most intense, noting that not all shade structures offer full protection. Protect your eyes, ears, face, and neck from the Sun by wearing a wide-brimmed hat. Caution! The reflection of sand and water significantly amplifies the Sun's UV radiation.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Dumai, Indonesia
- Average high temperature in September: 32.2°C
The warmest month (with the highest average high temperature) is June (32.8°C).
The months with the lowest average high temperature are January and December (30.6°C).
- Average low temperature in September: 24°C
The month with the highest average low temperature is May (24.7°C).
The coldest month (with the lowest average low temperature) is December (23.7°C).
Average pressure in September
Dumai, Indonesia
- Average pressure in September: 1009.8mbar
The months with the highest atmospheric pressure are January and February (1010.3mbar).
The month with the lowest atmospheric pressure is May (1008.8mbar).
Average wind speed in September
Dumai, Indonesia
- Average wind speed in September: 4.8km/h
The windiest month (with the highest average wind speed) is February (5.8km/h).
The calmest month (with the lowest average wind speed) is April (4.5km/h).
Average humidity in September
Dumai, Indonesia
- Average humidity in September: 79%
The months with the highest relative humidity are November and December (83%).
The month with the lowest relative humidity is February (78%).
Average rainfall in September
Dumai, Indonesia
- Average rainfall in September: 82mm
The wettest month (with the highest rainfall) is October (142mm).
The driest month (with the least rainfall) is February (52mm).
Average rainfall days in September
Dumai, Indonesia
- Average rainfall days in September: 24.6 days
The month with the highest number of rainy days is November (26.4 days).
The month with the least rainy days is February (18.7 days).
Average sea temperature in September
Dumai, Indonesia
- Average sea temperature in September: 29.4°C
The best months for swimming (with the highest average sea temperature) are May and June (30.2°C).
The coldest month (with the lowest average sea temperature) is January (28.4°C).
Average daylight in September /
Average sunshine in September
Dumai, Indonesia
- Average daylight in September: 12h and 6min
The month with the longest days is June (Average daylight: 12h and 12min).
The month with the shortest days is December (Average daylight: 12h and 0min).
- Average sunshine in September: 8h and 30min
The month with the most sunshine is October (Average sunshine: 8h and 48min).
The month with the least sunshine is December (Average sunshine: 7h and 0min).
Average sunshine days in September
Dumai, Indonesia
- Average sunshine days in September: 4.3 days
The month with the most sunshine days is June (7.2 days).
The month with the least sunshine days is November (3 days).
Average UV index in September
Dumai, Indonesia
- Average UV index in September: 7
The months with the highest UV index are January, February, March, April, May, June, July, August, September and November (UV index 7).
The months with the lowest UV index are October and December (UV index 6).
Average cloud cover in September
Dumai, Indonesia
- Average cloud cover in September: 41
The month with the most cloud cover is November (Cloud cover 54).
The months with the least cloud cover are February and June (Cloud cover 39).
Average visibility in September
Dumai, Indonesia
- Average visibility in September: 9km
The months with the highest visibility are January, February, March, April, May, June, July, August, September and October (9km).
The months with the lowest visibility are November and December (8km).
