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 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
The commencement of September involves a temperature shift, with the average high-temperature dropping from a warm 81.7°F (27.6°C) in August to an agreeable 70.9°F (21.6°C). The month of September sees a significant daily temperature drop, recording an average low-temperature of 49.1°F (9.5°C) in Fairfield.Humidity
In September, the average relative humidity is 39%.Rainfall
In Fairfield, during September, the rain falls for 6.2 days and regularly aggregates up to 0.43" (11mm) of precipitation. In Fairfield, during the entire year, the rain falls for 74.4 days and collects up to 8.03" (204mm) of precipitation.Snowfall
January through May, September through December are months with snowfall. September is the first month it typically snows. Throughout September, in the average 0.2 snowfall days, it receives 0.04" (1mm) of snow. In Fairfield, during the entire year, snow falls for 44.1 days and aggregates up to 29.65" (753mm) of snow.Daylight
In September, the average length of the day is 12h and 29min.On the first day of the month, sunrise is at 7:04 am and sunset at 8:13 pm. On the last day of September, sunrise is at 7:36 am and sunset at 7:21 pm MDT.
Sunshine
In September, the average sunshine in Fairfield is 9.6h.UV index
In Fairfield, the average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a medium vulnerability from unsafe exposure to UV radiation for the average person.Note: In September, the maximum UV index of 4 transforms into these recommendations:
Exercise prevention - Warding off sunburn is urged. Midday is when the Sun's radiation is strongest; avoid prolonged exposure during this time. Employ a hat with a wide brim for robust protection, cutting UV exposure by half. Take careful note! The UV radiation of the Sun can be nearly doubled by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are September temperatures?
What is the average humidity in September?
How much does it rain in September?
When does it start snowing?
What is the average length of the day in September?
What time are sunrise and sunset in September?
How many hours of sunshine does Fairfield have in September?
How high is the UV index in September?
Average temperature in September
Fairfield, ID
- Average high temperature in September: 70.9°F
The warmest month (with the highest average high temperature) is July (82.9°F).
The month with the lowest average high temperature is December (27.9°F).
- Average low temperature in September: 49.1°F
The months with the highest average low temperature are July and August (55.6°F).
The coldest month (with the lowest average low temperature) is January (14.4°F).
Average pressure in September
Fairfield, ID
- Average pressure in September: 29.94"Hg
The month with the highest atmospheric pressure is January (30.28"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed in September
Fairfield, ID
- Average wind speed in September: 6.6mph
The windiest months (with the highest average wind speed) are April and June (7.6mph).
The calmest month (with the lowest average wind speed) is December (5.3mph).
Average humidity in September
Fairfield, ID
- Average humidity in September: 39%
The month with the highest relative humidity is January (84%).
The month with the lowest relative humidity is August (32%).
Average rainfall in September
Fairfield, ID
- Average rainfall in September: 0.43"
The wettest month (with the highest rainfall) is February (1.02").
The driest month (with the least rainfall) is July (0.28").
Average rainfall days in September
Fairfield, ID
- Average rainfall days in September: 6.2 days
The month with the highest number of rainy days is May (12 days).
The month with the least rainy days is January (2.8 days).
Average snowfall in September
Fairfield, ID
- Average snowfall in September: 0.04"
The month with the highest snowfall is February (7.87").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Fairfield, ID
- Average snowfall days in September: 0.2 days
The month with the highest number of snowfall days is December (10.5 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Fairfield, ID
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- Average sunshine in September: 9h and 4min
The month with the most sunshine is July (Average sunshine: 12h and 0min).
The months with the least sunshine are January and December (Average sunshine: 5h and 54min).
Average sunshine days in September
Fairfield, ID
- Average sunshine days in September: 21.2 days
The month with the most sunshine days is October (23.5 days).
The month with the least sunshine days is May (15.6 days).
Average UV index in September
Fairfield, ID
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, March, October, November and December (UV index 2).
Average cloud cover in September
Fairfield, ID
- Average cloud cover in September: 13
The month with the most cloud cover is December (Cloud cover 38).
The month with the least cloud cover is July (Cloud cover 9).
Average visibility in September
Fairfield, ID
- Average visibility in September: 6mi
The months with the highest visibility are March, April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January, February and December (5mi).
Fairfield, Idaho, USA
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