September weather forecastWaimanalo, HI
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Waimanalo, Hawaii, with an average temperature varying between 80.6°F (27°C) and 77°F (25°C).Temperature
September, recognised by an average high temperature of 80.6°F (27°C) and a low of 77°F (25°C), is Waimanalo's warmest month.Heat index
In September, the heat index is appraised at 84.2°F (29°C). With constant exposure and activity, a state of weariness might ensue, leading to potential heat cramps.Understanding the heat index involves considering values for shaded locales with light wind. Exposure to the sun directly might heighten the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'felt air temperature', is calculated by taking the relative humidity value for a specific location and factoring it into the air temperature reading. The experience of temperature can be subjective, varying based on the individual's activity and heat perception, 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 quite important for babies and toddlers. Young ones often do not realize the necessity to rest and replenish their fluids. Thirst is a delayed indication of dehydration - keeping hydrated, particularly in prolonged physical activity, is crucial.
Humidity
In Waimanalo, the average relative humidity in September is 75%.Rainfall
In Waimanalo, during September, the rain falls for 13 days and regularly aggregates up to 0.94" (24mm) of precipitation. In Waimanalo, during the entire year, the rain falls for 169.9 days and collects up to 13.15" (334mm) of precipitation.Daylight
In Waimanalo, the average length of the day in September is 12h and 15min.On the first day of the month, sunrise is at 6:14 am and sunset at 6:46 pm. On the last day of September, sunrise is at 6:22 am and sunset at 6:19 pm HST.
Sunshine
In Waimanalo, the average sunshine in September is 9.3h.UV index
July through October, with an average maximum UV index of 7, are months with the highest UV index. A UV Index of 6 to 7 symbolizes a high health vulnerability from unprotected exposure to Sun's UV rays for ordinary individuals.Note: The UV index of 7 during September translates into the following guidance:
Guard against overexposure. Protection from sun-induced harm is essential. Be aware that the sun's UV radiation is strongest between 10 a.m. and 4 p.m. and try to reduce direct sun exposure during this period as much as possible. Employ a wide-brim hat for potent defense against up to 50% of UV rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Waimanalo, HI
- Average high temperature in September: 80.6°F
The warmest month (with the highest average high temperature) is September (80.6°F).
The month with the lowest average high temperature is February (74.5°F).
- Average low temperature in September: 77°F
The months with the highest average low temperature are September and October (77°F).
The coldest month (with the lowest average low temperature) is February (70.5°F).
Average pressure in September
Waimanalo, HI
- Average pressure in September: 29.97"Hg
The month with the highest atmospheric pressure is April (30.06"Hg).
The months with the lowest atmospheric pressure are September and October (29.97"Hg).
Average wind speed in September
Waimanalo, HI
- Average wind speed in September: 11.9mph
The windiest month (with the highest average wind speed) is July (14.1mph).
The calmest month (with the lowest average wind speed) is January (10.7mph).
Average humidity in September
Waimanalo, HI
- Average humidity in September: 75%
The months with the highest relative humidity are April, June, July, August and December (76%).
The months with the lowest relative humidity are January and November (74%).
Average rainfall in September
Waimanalo, HI
- Average rainfall in September: 0.94"
The wettest month (with the highest rainfall) is March (1.69").
The driest month (with the least rainfall) is July (0.55").
Average rainfall days in September
Waimanalo, HI
- Average rainfall days in September: 13 days
The month with the highest number of rainy days is March (16.9 days).
The month with the least rainy days is June (11.3 days).
Average daylight in September /
Average sunshine in September
Waimanalo, 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 12min).
The month with the least sunshine is December (Average sunshine: 6h and 36min).
Average sunshine days in September
Waimanalo, HI
- Average sunshine days in September: 11 days
The month with the most sunshine days is June (13.6 days).
The months with the least sunshine days are March and November (6.6 days).
Average UV index in September
Waimanalo, HI
- Average UV index in September: 7
The months with the highest UV index are July, August, September and October (UV index 7).
The months with the lowest UV index are January, February, March, April, May, June, November and December (UV index 6).
Average cloud cover in September
Waimanalo, HI
- Average cloud cover in September: 27
The month with the most cloud cover is March (Cloud cover 36).
The month with the least cloud cover is September (Cloud cover 27).
Average visibility in September
Waimanalo, 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).
