Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
Haiku's temperature records reveal September as the warmest month, marked by average highs of 79°F (26.1°C) and lows of 76.1°F (24.5°C).Humidity
In Haiku, 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
September is the only month when snow falls. The month with the most snowfall days is September, when snow falls for 0.1 days.Daylight
The average length of the day in September in Haiku, Hawaii, is 12h and 15min.On the first day of the month, sunrise is at 6:09 am and sunset at 6:40 pm. On the last day of September, in Haiku, sunrise is at 6:16 am and sunset at 6:13 pm HST.
Sunshine
The average sunshine in September in Haiku is 9.5h.UV index
The month with the highest UV index is September, with an average maximum UV index of 7. A UV Index value of 6 to 7 symbolizes a high health vulnerability from unsafe exposure to UV radiation for average individuals.Note: In September, a daily maximum UV index of 7 leads to the following instructions:
Sustain precautions and conform to sun safety norms. Preventing sunburn is necessary. The Sun's UV radiation is most potent between 10 a.m. and 4 p.m. Try to limit direct exposure to the Sun during this period. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses. Be mindful! The reflection from snow can increase the Sun's UV radiation nearly twice.
Frequently asked questions
What time of the year is the hottest in Haiku?
What are the temperatures in Haiku in September?
What is the average humidity in September in Haiku?
What is the driest month in Haiku?
How many days does it rain in September in Haiku?
What is the snowiest month in Haiku?
When does it start snowing in Haiku?
How many hours of daylight does Haiku have in September?
When is the sunrise / sunset in September in Haiku?
How many hours of sunshine does Haiku have in September?
What is the month with the highest UV index in Haiku?
How high is the UV index in September in Haiku?
Average temperature in September
Haiku, 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
Haiku, 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
Haiku, 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
Haiku, 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
Haiku, 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
Haiku, 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
Haiku, 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
Haiku, HI
- Average daylight in September: 12h and 2min
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 3min
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
Haiku, 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
Haiku, 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
Haiku, 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
Haiku, 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).
Haiku, Hawaii, USA
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