September weather forecastHolualoa, HI
September
Weather in September
The beginning of autumn is marked in September with a slight decrease in the average high temperature to 77°F (25°C). Nature flourishes, lending a unique charm to the city of Holualoa, Hawaii. The mild decline in temperature and the frequent rainfall rejuvenate the island, enhancing its tropical allure. This month is the start of the shift towards cooler months ahead.Temperature
The transition from August to September in Holualoa sees average high-temperatures adjusting to a still moderately hot 77°F (25°C), from a not significantly different 77.5°F (25.3°C). A consistent average low of 74.1°F (23.4°C) is noted throughout September, only a small step down from its daytime high.Humidity
In Holualoa, the average relative humidity in September is 78%.Rainfall
September is the month with the most rainfall. Rain falls for 15.5 days and accumulates 1.02" (26mm) of precipitation.Daylight
The average length of the day in September is 12h and 14min.On the first day of the month, sunrise is at 6:08 am and sunset at 6:38 pm. On the last day of September, sunrise is at 6:14 am and sunset at 6:12 pm HST.
Sunshine
In September, the average sunshine in Holualoa, Hawaii, is 9.3h.UV index
January through December, with an average maximum UV index of 6, are months with the highest UV index. The months with the lowest UV index in Holualoa are January through December, with an average maximum UV index of 6. A UV Index value 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 6 during September leads to these instructions:
Stand by precautions and apply sun safety measures. Evading sunburn is of great importance. Seek shade and minimize exposure to direct Sun in a period between 10 a.m. and 4 p.m. when UV radiation is most intense; keep in mind that shade structures like parasols or canopies do not provide perfect sun protection. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Holualoa, HI
- Average high temperature in September: 77°F
The warmest month (with the highest average high temperature) is August (77.5°F).
The month with the lowest average high temperature is February (72.7°F).
- Average low temperature in September: 74.1°F
The months with the highest average low temperature are August and October (74.3°F).
The coldest month (with the lowest average low temperature) is January (69.3°F).
Average pressure in September
Holualoa, HI
- Average pressure in September: 29.96"Hg
The month with the highest atmospheric pressure is April (30.04"Hg).
The months with the lowest atmospheric pressure are September and October (29.96"Hg).
Average wind speed in September
Holualoa, HI
- Average wind speed in September: 6mph
The windiest months (with the highest average wind speed) are April and May (6.2mph).
The calmest months (with the lowest average wind speed) are July and December (5.5mph).
Average humidity in September
Holualoa, HI
- Average humidity in September: 78%
The months with the highest relative humidity are July and August (79%).
The month with the lowest relative humidity is February (71%).
Average rainfall in September
Holualoa, HI
- Average rainfall in September: 1.02"
The wettest month (with the highest rainfall) is September (1.02").
The driest month (with the least rainfall) is January (0.47").
Average rainfall days in September
Holualoa, HI
- Average rainfall days in September: 15.5 days
The month with the highest number of rainy days is May (16.6 days).
The month with the least rainy days is January (8.3 days).
Average daylight in September /
Average sunshine in September
Holualoa, HI
- Average daylight in September: 12h and 12min
The month with the longest days is June (Average daylight: 13h and 18min).
The month with the shortest days is December (Average daylight: 11h and 0min).
- Average sunshine in September: 9h and 18min
The month with the most sunshine is May (Average sunshine: 11h and 12min).
The month with the least sunshine is December (Average sunshine: 7h and 24min).
Average sunshine days in September
Holualoa, HI
- Average sunshine days in September: 7.9 days
The month with the most sunshine days is January (17.6 days).
The month with the least sunshine days is May (6.7 days).
Average UV index in September
Holualoa, HI
- Average UV index in September: 6
The months with the highest UV index are January, February, March, April, May, June, July, August, September, October, November and December (UV index 6).
The months with the lowest UV index are January, February, March, April, May, June, July, August, September, October, November and December (UV index 6).
Average cloud cover in September
Holualoa, HI
- Average cloud cover in September: 21
The months with the most cloud cover are June and July (Cloud cover 24).
The month with the least cloud cover is January (Cloud cover 12).
Average visibility in September
Holualoa, 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).
