September weather forecastEwa Beach, HI
September
Weather in September
September in Ewa Beach witnesses an exquisite balance between the receding summer and the upcoming fall. The maintained ocean temperature underlines the persistent allure of the beachfront. The weather upholds the summer charm, facilitated by the pleasant temperatures and long beaches. However, the increasing rainfall and shrinking daylight hours subtly hint at the changing season. Meanwhile, the beach town basks in the outstanding Hawaiian climate, savoring the final beats of summer.Temperature
During August and September, Ewa Beach experiences its highest average temperatures, peaking at 81.5°F (27.5°C).Heat index
In September, the heat index is computed to be a hot 86°F (30°C). If one sustains activity during exposure, it could lead to a sense of fatigue, with a chance of heat cramps.Heat index values are typically calculated for conditions of shade and a light breeze. Direct sunlight might lead to a heat index increase by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', offers an insight into how hot it feels when we factor in moisture content. Elements such as metabolic variations, pregnancy, and physical exertion can influence one's weather perception. Always consider that direct sunlight exposure might heighten the heat's effects, pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values are largely significant for babies and toddlers. Children usually face more risks than adults as their ability to sweat is less. Additionally, their larger skin surface in relation to their petite bodies and higher heat output due to their activities increases their vulnerability.
Humidity
January, April through June, August through November, with an average relative humidity of 74%, are the least humid months.Rainfall
In Ewa Beach, in September, during 13.3 rainfall days, 0.83" (21mm) of precipitation is typically accumulated. Throughout the year, there are 172.2 rainfall days, and 12.72" (323mm) of precipitation is accumulated.Ocean temperature
The month with the warmest seawater is September, with an average ocean temperature of 80.6°F (27°C).Note: Water temperature ranging from 77°F (25°C) to 84.2°F (29°C) is recognized as warm and pleasant by all, making water activities comfortable and delightful for long durations.
Daylight
In September, the average length of the day is 12h and 15min.On the first day of the month, sunrise is at 6:15 am and sunset at 6:47 pm. On the last day of September, sunrise is at 6:23 am and sunset at 6:20 pm HST.
Sunshine
In Ewa Beach, the average sunshine in September is 9.3h.UV index
June through September, with an average maximum UV index of 7, are months with the highest UV index in Ewa Beach. A UV Index reading of 6 to 7 represents a high health risk from exposure to the Sun's UV rays for ordinary individuals.Note: The daily high UV index of 7 during September translates into the following recommendations:
Incorporate safeguards and honour sun safety principles. Protection from skin and eye damage is obligatory. Between 10 a.m. and 4 p.m., UV radiation is strongest. Make an effort to avoid direct sunlight during this time, remembering that shade structures may not provide full sun protection. For minimizing sun-related eye damage, always choose sunglasses with UVA and UVB coverage. Alert! UV radiation becomes sharper due to reflections from sand and water.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Ewa Beach, HI
- Average high temperature in September: 81.5°F
The warmest months (with the highest average high temperature) are August and September (81.5°F).
The month with the lowest average high temperature is February (74.8°F).
- Average low temperature in September: 76.3°F
The months with the highest average low temperature are August and September (76.3°F).
The coldest month (with the lowest average low temperature) is February (69.4°F).
Average pressure in September
Ewa Beach, HI
- Average pressure in September: 29.97"Hg
The months with the highest atmospheric pressure are March and April (30.05"Hg).
The months with the lowest atmospheric pressure are September and October (29.97"Hg).
Average wind speed in September
Ewa Beach, HI
- Average wind speed in September: 9.8mph
The windiest month (with the highest average wind speed) is July (11.9mph).
The calmest months (with the lowest average wind speed) are January and October (9.1mph).
Average humidity in September
Ewa Beach, HI
- Average humidity in September: 74%
The month with the highest relative humidity is December (76%).
The months with the lowest relative humidity are January, April, May, June, August, September, October and November (74%).
Average rainfall in September
Ewa Beach, HI
- Average rainfall in September: 0.83"
The wettest month (with the highest rainfall) is March (1.77").
The driest month (with the least rainfall) is July (0.43").
Average rainfall days in September
Ewa Beach, HI
- Average rainfall days in September: 13.3 days
The month with the highest number of rainy days is March (18.1 days).
The month with the least rainy days is July (11.3 days).
Average sea temperature in September
Ewa Beach, HI
- Average sea temperature in September: 80.6°F
The best month for swimming (with the highest average sea temperature) is September (80.6°F).
The coldest month (with the lowest average sea temperature) is March (75.7°F).
Average daylight in September /
Average sunshine in September
Ewa Beach, HI
- Average daylight in September: 12h and 18min
The month with the longest days is June (Average daylight: 13h and 24min).
The month with the shortest days is December (Average daylight: 10h and 54min).
- Average sunshine in September: 9h and 18min
The month with the most sunshine is June (Average sunshine: 11h and 0min).
The month with the least sunshine is November (Average sunshine: 6h and 42min).
Average sunshine days in September
Ewa Beach, HI
- Average sunshine days in September: 12.2 days
The months with the most sunshine days are July and August (15.3 days).
The month with the least sunshine days is March (6.8 days).
Average UV index in September
Ewa Beach, HI
- Average UV index in September: 7
The months with the highest UV index are June, July, August and September (UV index 7).
The months with the lowest UV index are January, February, March, April, May, October, November and December (UV index 6).
Average cloud cover in September
Ewa Beach, HI
- Average cloud cover in September: 30
The month with the most cloud cover is March (Cloud cover 37).
The month with the least cloud cover is September (Cloud cover 30).
Average visibility in September
Ewa Beach, HI
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
