September weather forecastStanley, ID
September
Weather in September
September signifies the commencement of fall in Stanley. The landscape begins to shift its colours as temperatures start to decline, averaging 62.1°F (16.7°C) in the daytime. An increase in rainfall from the summer months rehydrates the environment preparing it for the upcoming cold months. Residents and visitors alike revel in the changing seasons, watching as the surroundings transition from vibrant summer greens to the orange hues of fall.Temperature
The transition into September involves a decrease in the average high-temperature, falling from a pleasant 71.4°F (21.9°C) in August to a comfortable 62.1°F (16.7°C). Stanley experiences a substantial divergence from daytime highs in September, with average lows hovering around an icy 36.5°F (2.5°C).Humidity
The average relative humidity in September is 53%.Rainfall
In Stanley, in September, it is raining for 9.5 days, with typically 1.18" (30mm) of accumulated precipitation. Throughout the year, there are 98.2 rainfall days, and 19.25" (489mm) of precipitation is accumulated.Snowfall
January through June, September through December are months with snowfall in Stanley. September is the first month it typically snows in Stanley. Throughout September, in the average 1.5 snowfall days, it receives 1.38" (35mm) of snow. In Stanley, during the entire year, snow falls for 131.3 days and aggregates up to 100.24" (2546mm) of snow.Daylight
The average length of the day in September is 12h and 29min.On the first day of the month, sunrise is at 7:03 am and sunset at 8:15 pm. On the last day of September, sunrise is at 7:37 am and sunset at 7:21 pm MDT.
Sunshine
In Stanley, the average sunshine in September is 9h.UV index
The average daily maximum UV index in September is 2. A UV Index reading of 2, and below, represents a minimal health vulnerability from unsafe exposure to UV radiation for the ordinary person.Note: The maximum daily UV index, 2 in September, converts into the following recommendations:
Many can withstand an hour in the sun without burning, yet children must always have protection against sunlight. The intensity of the Sun's UV radiation during midday suggests reducing time spent outdoors. Using UVA and UVB-protective sunglasses and sun-protective clothing is effective against UV radiation. Watch out! The Sun's UV radiation can be nearly magnified twofold due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Stanley, ID
- Average high temperature in September: 62.1°F
The warmest month (with the highest average high temperature) is July (72.7°F).
The month with the lowest average high temperature is December (23.9°F).
- Average low temperature in September: 36.5°F
The month with the highest average low temperature is July (43.3°F).
The coldest month (with the lowest average low temperature) is December (5.4°F).
Average pressure in September
Stanley, ID
- Average pressure in September: 29.96"Hg
The month with the highest atmospheric pressure is January (30.26"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Stanley, ID
- Average wind speed in September: 5mph
The windiest month (with the highest average wind speed) is July (5.8mph).
The calmest months (with the lowest average wind speed) are January and October (4.8mph).
Average humidity in September
Stanley, ID
- Average humidity in September: 53%
The months with the highest relative humidity are February and March (91%).
The month with the lowest relative humidity is July (44%).
Average rainfall in September
Stanley, ID
- Average rainfall in September: 1.18"
The wettest month (with the highest rainfall) is March (2.17").
The driest months (with the least rainfall) are July and August (0.63").
Average rainfall days in September
Stanley, ID
- Average rainfall days in September: 9.5 days
The month with the highest number of rainy days is May (16.3 days).
The month with the least rainy days is January (3.1 days).
Average snowfall in September
Stanley, ID
- Average snowfall in September: 1.38"
The month with the highest snowfall is December (16.77").
The months with the least snowfall are July and August (0").
Average snowfall days in September
Stanley, ID
- Average snowfall days in September: 1.5 days
The month with the highest number of snowfall days is March (21.6 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in September /
Average sunshine in September
Stanley, ID
- Average daylight in September: 12h and 30min
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 0min
The month with the most sunshine is July (Average sunshine: 11h and 48min).
The months with the least sunshine are January and December (Average sunshine: 4h and 24min).
Average sunshine days in September
Stanley, ID
- Average sunshine days in September: 18.2 days
The month with the most sunshine days is July (20 days).
The month with the least sunshine days is April (8.1 days).
Average UV index in September
Stanley, ID
- Average UV index in September: 2
The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, March and November (UV index 1).
Average cloud cover in September
Stanley, ID
- Average cloud cover in September: 20
The month with the most cloud cover is February (Cloud cover 65).
The month with the least cloud cover is July (Cloud cover 12).
Average visibility in September
Stanley, ID
- Average visibility in September: 6mi
The months with the highest visibility are June, July, August, September and October (6mi).
The month with the lowest visibility is February (3mi).
