September weather forecastKaumalapau, HI
September
Weather in September
September, the first month of the autumn in Kaumalapau, is still a warm month, with an average temperature ranging between min 77.4°F (25.2°C) and max 81°F (27.2°C).Temperature
The month of September sees the highest average temperatures, reaching 81°F (27.2°C) at the peak and 77.4°F (25.2°C) at the low.Heat index
The heat index for September is evaluated at a hot 86°F (30°C). If one stays active during extended exposure, it might induce fatigue and result in heat cramps.In the scope of the heat index, its values resonate with shade and light wind conditions. Direct sunlight has the potential to heighten heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', is an indicator that blends the effects of temperature and humidity to depict perceived warmth. Depending on the activity and the individual's heat perception, which may vary due to factors including wind, clothing, and metabolic variations, this effect remains subjective. Keep it in mind, direct sunlight can augment the heat you experience, possibly pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly important for children. Young individuals are typically more threatened than adults due to their reduced perspiration. Also, the larger skin surface proportionate to their small bodies and the increased heat from their activities magnify their risk.
Humidity
In Kaumalapau, the average relative humidity in September is 74%.Rainfall
In Kaumalapau, during September, the rain falls for 7.1 days and regularly aggregates up to 0.43" (11mm) of precipitation. In Kaumalapau, during the entire year, the rain falls for 98.9 days and collects up to 7.64" (194mm) of precipitation.Snowfall
September is the only month when snow falls. September has the most snowfall days of the year in Kaumalapau. Snow falls for 0.1 days.Daylight
In September, the average length of the day in Kaumalapau is 12h and 15min.On the first day of September, sunrise is at 6:12 am and sunset at 6:43 pm. On the last day of the month, sunrise is at 6:18 am and sunset at 6:16 pm HST.
Sunshine
In September, the average sunshine in Kaumalapau is 9.8h.UV index
May 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 risk from unprotected exposure to Sun's UV rays for the average person.Note: The average daily UV index of 7 in September transforms into the following instructions:
Inhibit overexposure. Warding off sun damage is of utmost importance. Stay in the shade and limit sun exposure from 10 a.m. to 4 p.m., when UV radiation is most potent. Keep in mind that shade structures like parasols or canopies do not offer full protection. To cut down UV radiation exposure by about half, sport a wide-brim hat. Beware! Reflection from snow can magnify the Sun's UV radiation nearly twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Kaumalapau, HI
- Average high temperature in September: 81°F
The warmest month (with the highest average high temperature) is September (81°F).
The month with the lowest average high temperature is February (74.8°F).
- Average low temperature in September: 77.4°F
The months with the highest average low temperature are August and October (77.5°F).
The coldest month (with the lowest average low temperature) is March (71.6°F).
Average pressure in September
Kaumalapau, HI
- Average pressure in September: 29.97"Hg
The month with the highest atmospheric pressure is April (30.05"Hg).
The month with the lowest atmospheric pressure is October (29.96"Hg).
Average wind speed in September
Kaumalapau, HI
- Average wind speed in September: 9.7mph
The windiest months (with the highest average wind speed) are March and November (10.9mph).
The calmest month (with the lowest average wind speed) is October (9mph).
Average humidity in September
Kaumalapau, HI
- Average humidity in September: 74%
The month with the highest relative humidity is July (75%).
The months with the lowest relative humidity are January and November (73%).
Average rainfall in September
Kaumalapau, HI
- Average rainfall in September: 0.43"
The wettest month (with the highest rainfall) is March (1.26").
The driest month (with the least rainfall) is July (0.16").
Average rainfall days in September
Kaumalapau, HI
- Average rainfall days in September: 7.1 days
The month with the highest number of rainy days is March (12.7 days).
The month with the least rainy days is July (4.7 days).
Average snowfall days in September
Kaumalapau, 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
Kaumalapau, 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 48min
The month with the most sunshine is June (Average sunshine: 11h and 36min).
The month with the least sunshine is December (Average sunshine: 7h and 6min).
Average sunshine days in September
Kaumalapau, HI
- Average sunshine days in September: 21.5 days
The month with the most sunshine days is July (25.6 days).
The month with the least sunshine days is February (12.7 days).
Average UV index in September
Kaumalapau, HI
- Average UV index in September: 7
The months with the highest UV index are May, June, July, August, September and October (UV index 7).
The months with the lowest UV index are January, February, March, April, November and December (UV index 6).
Average cloud cover in September
Kaumalapau, HI
- Average cloud cover in September: 18
The month with the most cloud cover is March (Cloud cover 27).
The month with the least cloud cover is September (Cloud cover 18).
Average visibility in September
Kaumalapau, 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).
