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, May sees a drop in the average high-temperature, transitioning from a moderately hot 75.4°F (24.1°C) to a comfortable 65.7°F (18.7°C). May anticipates a considerable drop in temperature at night in September, with an average low of 41.5°F (5.3°C).Humidity
In September, the average relative humidity is 45%.Rainfall
In May, in September, it is raining for 6.9 days, with typically 0.51" (13mm) of accumulated precipitation. Throughout the year, there are 75.7 rainfall days, and 6.38" (162mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through June, September through December. September is the first month it typically snows. Throughout September, in the average 0.5 snowfall days, it receives 0.67" (17mm) of snow. In May, during the entire year, snow falls for 51.7 days and aggregates up to 18.62" (473mm) of snow.Daylight
In September, the average length of the day is 12h and 30min.On the first day of the month, sunrise is at 6:59 am and sunset at 8:11 pm. On the last day of September, sunrise is at 7:33 am and sunset at 7:17 pm MDT.
Sunshine
In September, the average sunshine is 9.5h.UV index
In September, the average daily maximum UV index is 3. A UV Index value of 3 to 5 symbolizes a medium health hazard from unprotected exposure to Sun's UV rays for the ordinary person.Note: In September, the maximum UV index of 3 transforms into these recommendations:
Heed the precautions - Protecting the skin and eyes from damage is compulsory. Sun's radiation is most powerful around mid-day, so it's best to limit outdoor activities during this time. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades. Be advised! The UV radiation from the Sun can be almost doubled due to the reflective properties of snow.
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Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are September temperatures in May?
What is the average humidity in September?
How many days does it rain in September?
When does it start to snow?
How many hours of daylight does May have in September?
What time are sunrise and sunset in September?
How many hours of sunshine does May have in September?
What is the UV index intensity in September?
Average temperature in September
May, ID
- Average high temperature in September: 65.7°F
The warmest month (with the highest average high temperature) is July (76.6°F).
The month with the lowest average high temperature is December (26.1°F).
- Average low temperature in September: 41.5°F
The month with the highest average low temperature is August (47.8°F).
The coldest month (with the lowest average low temperature) is January (8.1°F).
Average pressure in September
May, ID
- Average pressure in September: 29.98"Hg
The month with the highest atmospheric pressure is January (30.27"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
May, ID
- Average wind speed in September: 5.2mph
The windiest months (with the highest average wind speed) are June and July (5.7mph).
The calmest month (with the lowest average wind speed) is January (4.8mph).
Average humidity in September
May, ID
- Average humidity in September: 45%
The month with the highest relative humidity is February (87%).
The months with the lowest relative humidity are July and August (38%).
Average rainfall in September
May, ID
- Average rainfall in September: 0.51"
The wettest month (with the highest rainfall) is June (1.1").
The driest month (with the least rainfall) is July (0.28").
Average rainfall days in September
May, ID
- Average rainfall days in September: 6.9 days
The month with the highest number of rainy days is June (10.2 days).
The month with the least rainy days is January (3.8 days).
Average snowfall in September
May, ID
- Average snowfall in September: 0.67"
The month with the highest snowfall is February (3.54").
The months with the least snowfall are July and August (0").
Average snowfall days in September
May, ID
- Average snowfall days in September: 0.5 days
The month with the highest number of snowfall days is December (10.1 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in September /
Average sunshine in September
May, ID
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 30min).
The month with the shortest days is December (Average daylight: 8h and 54min).
- Average sunshine in September: 9h and 3min
The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is January (Average sunshine: 5h and 48min).
Average sunshine days in September
May, ID
- Average sunshine days in September: 21.6 days
The month with the most sunshine days is July (24.1 days).
The months with the least sunshine days are March and April (17.2 days).
Average UV index in September
May, ID
- Average UV index in September: 3
The months with the highest UV index are June and July (UV index 5).
The months with the lowest UV index are January, February, March, April, October, November and December (UV index 2).
Average cloud cover in September
May, ID
- Average cloud cover in September: 16
The month with the most cloud cover is February (Cloud cover 44).
The month with the least cloud cover is July (Cloud cover 11).
Average visibility in September
May, ID
- Average visibility in September: 6mi
The months with the highest visibility are April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January and February (4mi).
May, Idaho, USA
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