September weather forecastKeoneoio, HI
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Keoneoio, Hawaii, with an average temperature fluctuating between 79°F (26.1°C) and 76.1°F (24.5°C).Temperature
Keoneoio, Hawaii, reaches its highest average temperatures in September, measuring 79°F (26.1°C) at the peak and 76.1°F (24.5°C) at the lowest.Humidity
The average relative humidity in September is 77%.Rainfall
The month with the least rainfall is September, when the rain falls for 8.1 days and typically collects 0.43" (11mm) of precipitation.Snowfall
The only month with snowfall is September. The month with the most snowfall days is September, when snow falls for 0.1 days.Daylight
In Keoneoio, Hawaii, the average length of the day in September is 12h and 15min.On the first day of September, sunrise is at 6:09 am and sunset at 6:40 pm. On the last day of the month, sunrise is at 6:16 am and sunset at 6:14 pm HST.
Sunshine
In September, the average sunshine is 9.5h.UV index
September is the month with the highest UV index, with an average maximum UV index of 7. A UV Index value of 6 to 7 symbolizes a high threat to health from unprotected exposure to Sun's UV rays for ordinary individuals.Note: The maximum UV index, 7 during September, leads to the following recommendations:
Enforce precautions and stick to sun safety measures. Preservation from skin and eye damage is essential. It's important to stay in the shade and limit exposure to the sun from 10 a.m. to 4 p.m., when UV radiation is most intense, although remember that shade structures may not provide full sun protection. Employ a hat with a wide brim for robust protection, cutting UV exposure by half. Foresee this! The reflection from snow can nearly double the intensity of UV radiation from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Keoneoio, HI
- Average high temperature in September: 79°F
The warmest month (with the highest average high temperature) is September (79°F).
The month with the lowest average high temperature is March (72.9°F).
- Average low temperature in September: 76.1°F
The month with the highest average low temperature is September (76.1°F).
The coldest month (with the lowest average low temperature) is March (69.8°F).
Average pressure in September
Keoneoio, 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
Keoneoio, HI
- Average wind speed in September: 12.6mph
The windiest month (with the highest average wind speed) is June (14.4mph).
The calmest month (with the lowest average wind speed) is January (10.9mph).
Average humidity in September
Keoneoio, HI
- Average humidity in September: 77%
The months with the highest relative humidity are July and August (78%).
The months with the lowest relative humidity are January and February (76%).
Average rainfall in September
Keoneoio, HI
- Average rainfall in September: 0.43"
The wettest month (with the highest rainfall) is October (2.17").
The driest month (with the least rainfall) is September (0.43").
Average rainfall days in September
Keoneoio, HI
- Average rainfall days in September: 8.1 days
The month with the highest number of rainy days is March (14.1 days).
The month with the least rainy days is September (8.1 days).
Average snowfall days in September
Keoneoio, HI
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is September (0.1 days).
The months with the least snowfall days are January, February, March, April, May, June, July, August, October, November and December (0 days).
Average daylight in September /
Average sunshine in September
Keoneoio, HI
- Average daylight in September: 12h and 12min
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 30min
The months with the most sunshine are June and July (Average sunshine: 11h and 18min).
The month with the least sunshine is December (Average sunshine: 6h and 42min).
Average sunshine days in September
Keoneoio, HI
- Average sunshine days in September: 15.5 days
The month with the most sunshine days is January (16.8 days).
The month with the least sunshine days is November (11.2 days).
Average UV index in September
Keoneoio, HI
- Average UV index in September: 7
The month with the highest UV index is September (UV index 7).
The months with the lowest UV index are January, February, March, April, May, June, July, August, October, November and December (UV index 6).
Average cloud cover in September
Keoneoio, HI
- Average cloud cover in September: 23
The month with the most cloud cover is March (Cloud cover 33).
The month with the least cloud cover is September (Cloud cover 23).
Average visibility in September
Keoneoio, 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).
