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 onset brings a reduction in the average high-temperature, from a moderately hot 74.7°F (23.7°C) in August to a comfortable 65.3°F (18.5°C). Lemhi observes a substantial disparity between daytime high and the average low-temperature of 40.6°F (4.8°C) during September nights.Humidity
In Lemhi, the average relative humidity in September is 50%.Rainfall
In September, the rain falls for 9.4 days. Throughout September, 0.94" (24mm) of precipitation is accumulated. Throughout the year, there are 129.5 rainfall days, and 12.4" (315mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, September through December. September is the first month it typically snows. Throughout September, in the average 0.3 snowfall days, it receives 0.43" (11mm) of snow. In Lemhi, during the entire year, snow falls for 63.5 days and aggregates up to 22.76" (578mm) of snow.Daylight
In September, the average length of the day is 12h and 30min.On the first day of September, sunrise is at 6:57 am and sunset at 8:10 pm. On the last day of the month, sunrise is at 7:32 am and sunset at 7:16 pm MDT.
Sunshine
In Lemhi, the average sunshine in September is 9.4h.UV index
In September, the average daily maximum UV index is 3. A UV Index value of 3 to 5 symbolizes a moderate health risk from unsafe exposure to UV radiation for the average person.Note: A daily high UV index of 3 in September leads to these guidelines:
Take precautions - Protection against skin and eye damage is obliged. The Sun's most harmful UV rays are emitted around midday; avoid staying outdoors for long during this time. Sunglasses that guard against UVA and UVB rays are pivotal in minimizing sun-induced ocular damage. Be on the lookout! Nearly twofold UV radiation from the Sun can be reflected by snow.
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 to snow?
How many hours of daylight does Lemhi have in September?
When are sunrise and sunset in September in Lemhi?
How many hours of sunshine does Lemhi have in September?
How high is the UV index in September?
Average temperature in September
Lemhi, ID
- Average high temperature in September: 65.3°F
The warmest month (with the highest average high temperature) is July (75.7°F).
The month with the lowest average high temperature is December (25.2°F).
- Average low temperature in September: 40.6°F
The month with the highest average low temperature is August (47.5°F).
The coldest months (with the lowest average low temperature) are January and December (9.5°F).
Average pressure in September
Lemhi, ID
- Average pressure in September: 29.99"Hg
The month with the highest atmospheric pressure is January (30.25"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Lemhi, ID
- Average wind speed in September: 4.5mph
The windiest months (with the highest average wind speed) are March and April (5.2mph).
The calmest month (with the lowest average wind speed) is August (4.3mph).
Average humidity in September
Lemhi, ID
- Average humidity in September: 50%
The month with the highest relative humidity is February (89%).
The month with the lowest relative humidity is August (43%).
Average rainfall in September
Lemhi, ID
- Average rainfall in September: 0.94"
The wettest month (with the highest rainfall) is June (2.05").
The driest months (with the least rainfall) are July and August (0.51").
Average rainfall days in September
Lemhi, ID
- Average rainfall days in September: 9.4 days
The month with the highest number of rainy days is May (18.3 days).
The month with the least rainy days is January (6.3 days).
Average snowfall in September
Lemhi, ID
- Average snowfall in September: 0.43"
The month with the highest snowfall is February (5").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Lemhi, ID
- Average snowfall days in September: 0.3 days
The month with the highest number of snowfall days is February (12.3 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Lemhi, 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 2min
The month with the most sunshine is July (Average sunshine: 11h and 48min).
The month with the least sunshine is January (Average sunshine: 5h and 6min).
Average sunshine days in September
Lemhi, ID
- Average sunshine days in September: 17.7 days
The month with the most sunshine days is July (19.4 days).
The month with the least sunshine days is April (7.7 days).
Average UV index in September
Lemhi, 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 and December (UV index 1).
Average cloud cover in September
Lemhi, ID
- Average cloud cover in September: 19
The month with the most cloud cover is February (Cloud cover 53).
The month with the least cloud cover is August (Cloud cover 13).
Average visibility in September
Lemhi, 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 (4mi).
Lemhi, Idaho, USA
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