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
September's arrival comes with a decrease in the average high-temperature, moving from a moderately hot 78.4°F (25.8°C) in August to an agreeable 68.7°F (20.4°C). September nights present a stark temperature decrease to a cold 41.9°F (5.5°C).Humidity
The average relative humidity in September is 62%.Rainfall
In September, the rain falls for 9 days. Throughout September, 0.94" (24mm) of precipitation is accumulated. Throughout the year, there are 140.1 rainfall days, and 22.2" (564mm) of precipitation is accumulated.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 0.43" (11mm) of snow. In Smelterville, during the entire year, snow falls for 57.8 days and aggregates up to 45.31" (1151mm) of snow.Daylight
The average length of the day in September is 12h and 33min.On the first day of September, sunrise is at 6:04 am and sunset at 7:24 pm. On the last day of the month, sunrise is at 6:43 am and sunset at 6:25 pm PDT.
Sunshine
The average sunshine in September in Smelterville is 9.5h.UV index
The average daily maximum UV index in September is 3. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for average individuals.Note: The maximum daily UV index of 3 in September interprets into the following recommendations:
Be vigilant - A duty to shield skin and eyes from injury exists. The midday Sun can be dangerous due to its intense radiation; always find shade and reduce exposure. Consider a wide-brim hat essential for effective sun defense covering your face, neck, and eyes. Note this! The Sun's UV radiation can nearly be doubled by the reflection off snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature?
What is the average humidity in September?
How much does it rain in September?
When does it start to snow?
What is the average length of the day in September?
What time are sunrise and sunset in September?
How many hours of sunshine does Smelterville have in September?
What is the UV index reading in September?
Average temperature in September
Smelterville, ID
- Average high temperature in September: 68.7°F
The warmest month (with the highest average high temperature) is August (78.4°F).
The month with the lowest average high temperature is December (30.4°F).
- Average low temperature in September: 41.9°F
The month with the highest average low temperature is August (49.8°F).
The coldest month (with the lowest average low temperature) is December (19.8°F).
Average pressure in September
Smelterville, ID
- Average pressure in September: 29.97"Hg
The month with the highest atmospheric pressure is January (30.19"Hg).
The months with the lowest atmospheric pressure are June and August (29.92"Hg).
Average wind speed in September
Smelterville, ID
- Average wind speed in September: 4mph
The windiest month (with the highest average wind speed) is April (4.8mph).
The calmest months (with the lowest average wind speed) are September and December (4mph).
Average humidity in September
Smelterville, ID
- Average humidity in September: 62%
The month with the highest relative humidity is January (92%).
The month with the lowest relative humidity is August (52%).
Average rainfall in September
Smelterville, ID
- Average rainfall in September: 0.94"
The wettest month (with the highest rainfall) is January (2.8").
The driest month (with the least rainfall) is July (0.51").
Average rainfall days in September
Smelterville, ID
- Average rainfall days in September: 9 days
The month with the highest number of rainy days is March (17.8 days).
The month with the least rainy days is August (6.3 days).
Average snowfall in September
Smelterville, ID
- Average snowfall in September: 0.43"
The month with the highest snowfall is January (12.36").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Smelterville, ID
- Average snowfall days in September: 0.2 days
The month with the highest number of snowfall days is December (13.5 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Smelterville, ID
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in September: 9h and 3min
The month with the most sunshine is August (Average sunshine: 11h and 48min).
The months with the least sunshine are January and December (Average sunshine: 3h and 36min).
Average sunshine days in September
Smelterville, ID
- Average sunshine days in September: 19.6 days
The month with the most sunshine days is July (22.9 days).
The month with the least sunshine days is March (8.7 days).
Average UV index in September
Smelterville, ID
- Average UV index in September: 3
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 1).
Average cloud cover in September
Smelterville, ID
- Average cloud cover in September: 25
The months with the most cloud cover are January, February and December (Cloud cover 64).
The month with the least cloud cover is August (Cloud cover 14).
Average visibility in September
Smelterville, ID
- Average visibility in September: 6mi
The months with the highest visibility are May, June, July, August and September (6mi).
The months with the lowest visibility are January, February and December (3mi).
Smelterville, Idaho, USA
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