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
As August transitions into September, Darby sees a drop in the average high-temperature, transitioning from a warm 74.1°F (23.4°C) to an enjoyable 64.9°F (18.3°C). Despite a noticeable differential from daytime highs, Darby notes an average nighttime low-temperature of 40.1°F (4.5°C) in September.Humidity
In September, the average relative humidity is 54%.Rainfall
In Darby, during September, the rain falls for 9.5 days and regularly aggregates up to 1.65" (42mm) of precipitation. In Darby, during the entire year, the rain falls for 96.6 days and collects up to 32.95" (837mm) of precipitation.Snowfall
January through June, August through December are months with snowfall. In Darby, in September, during 2.5 snowfall days, 4.49" (114mm) of snow is typically accumulated. In Darby, Idaho, during the entire year, snow falls for 160.8 days and aggregates up to 200.16" (5084mm) 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 6:48 am and sunset at 7:59 pm. On the last day of September, sunrise is at 7:21 am and sunset at 7:06 pm MDT.
Sunshine
The average sunshine in September is 9.9h.UV index
In September, the average daily maximum UV index is 3. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV radiation for the ordinary person.Note: The maximum daily UV index of 3 in September converts into the following recommendations:
Make use of precautions - It is urged to ward off sun damage. The mid-day Sun emits the most powerful UV radiation, so seek shade and minimize exposure. On days when the sun blazes, arm yourself with sunglasses that block UVA and UVB radiation. Be aware! The reflective nature of snow can magnify the Sun's UV radiation almost twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the usual temperature for Darby in September?
What is the average humidity in September in Darby?
How many days does it rain in September?
How many days does it snow in September?
What is the average length of the day in September?
When is the sunrise / sunset in September?
How long on average sun shines in September?
What is the UV index reading in September?
Average temperature in September
Darby, ID
- Average high temperature in September: 64.9°F
The warmest month (with the highest average high temperature) is July (75.4°F).
The month with the lowest average high temperature is December (23.2°F).
- Average low temperature in September: 40.1°F
The month with the highest average low temperature is July (46.9°F).
The coldest month (with the lowest average low temperature) is December (7.7°F).
Average pressure in September
Darby, ID
- Average pressure in September: 29.99"Hg
The month with the highest atmospheric pressure is January (30.27"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Darby, ID
- Average wind speed in September: 5.6mph
The windiest month (with the highest average wind speed) is June (6.2mph).
The calmest months (with the lowest average wind speed) are January and December (4.8mph).
Average humidity in September
Darby, ID
- Average humidity in September: 54%
The month with the highest relative humidity is February (94%).
The month with the lowest relative humidity is August (47%).
Average rainfall in September
Darby, ID
- Average rainfall in September: 1.65"
The wettest month (with the highest rainfall) is February (4.13").
The driest month (with the least rainfall) is July (0.91").
Average rainfall days in September
Darby, ID
- Average rainfall days in September: 9.5 days
The month with the highest number of rainy days is May (15.5 days).
The month with the least rainy days is January (3 days).
Average snowfall in September
Darby, ID
- Average snowfall in September: 4.49"
The month with the highest snowfall is February (34.33").
The month with the least snowfall is July (0").
Average snowfall days in September
Darby, ID
- Average snowfall days in September: 2.5 days
The month with the highest number of snowfall days is March (23.6 days).
The month with the least snowfall days is July (0.1 days).
Average daylight in September /
Average sunshine in September
Darby, ID
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 24min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- Average sunshine in September: 9h and 5min
The month with the most sunshine is July (Average sunshine: 11h and 42min).
The month with the least sunshine is February (Average sunshine: 3h and 18min).
Average sunshine days in September
Darby, ID
- Average sunshine days in September: 16.7 days
The month with the most sunshine days is July (20.3 days).
The month with the least sunshine days is April (6.2 days).
Average UV index in September
Darby, ID
- Average UV index in September: 3
The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, March, October, November and December (UV index 1).
Average cloud cover in September
Darby, ID
- Average cloud cover in September: 20
The month with the most cloud cover is February (Cloud cover 73).
The month with the least cloud cover is August (Cloud cover 14).
Average visibility in September
Darby, ID
- Average visibility in September: 6mi
The months with the highest visibility are May, June, July, August, September and October (6mi).
The months with the lowest visibility are January, February, March and December (3mi).
Darby, Idaho, USA
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