September weather forecastIsland Park, ID
September
Weather in September
In Island Park, September is a blend of lingering summer warmth and the incoming cooler temperatures of autumn. Days remain relatively warm, but nights become increasingly chilly as the month progresses. A visible increase in rainfall, from 0.71" (18mm) to 1.14" (29mm), and a decrease in temperature is a clear herald of autumn's onset. The town begins to take on a multicolored façade as leaves turn into shades of red, yellow, and orange, making it an appealing month for leaf-peeping.Temperature
A shift in the average high-temperature occurs in September in Island Park, reducing from a warm 75.7°F (24.3°C) in August to an enjoyable 65.8°F (18.8°C). Nighttime in September brings a stark departure from the daily high in Island Park, resting at an average low-temperature of 40.1°F (4.5°C).Humidity
The average relative humidity in September is 53%.Rainfall
In Island Park, during September, the rain falls for 7.9 days and regularly aggregates up to 1.14" (29mm) of precipitation. In Island Park, during the entire year, the rain falls for 106.1 days and collects up to 20.83" (529mm) of precipitation.Snowfall
January through July, September through December are months with snowfall. September is the first month it typically snows in Island Park. Throughout September, in the average 1.2 snowfall days, it receives 1.69" (43mm) of snow. Throughout the year, in Island Park, Idaho, there are 138.1 snowfall days, and 107.64" (2734mm) of snow is accumulated.Daylight
In Island Park, the average length of the day in September is 12h and 30min.On the first day of September, sunrise is at 6:49 am and sunset at 8:01 pm. On the last day of the month, sunrise is at 7:23 am and sunset at 7:07 pm MDT.
Sunshine
The average sunshine in September in Island Park is 9.9h.UV index
In September, the average daily maximum UV index in Island Park is 3. A UV Index estimate of 3 to 5 represents a moderate health risk from exposure to the Sun's UV radiation for ordinary individuals.Note: A maximum UV index of 3 in September translates into the following recommendations:
Preventative actions are necessary - Recommendations to ward off sunburn are given. It's crucial to reduce time in the direct Sun around mid-day due to the intense solar radiation. Safeguard your eyes, ears, and face from sun rays with the aid of a wide-brim hat. Mind you! Snow reflection can increase the intensity of the Sun's UV radiation nearly twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Island Park, ID
- Average high temperature in September: 65.8°F
The warmest month (with the highest average high temperature) is July (77.4°F).
The month with the lowest average high temperature is December (22.3°F).
- Average low temperature in September: 40.1°F
The month with the highest average low temperature is August (46.6°F).
The coldest months (with the lowest average low temperature) are January and December (6.8°F).
Average pressure in September
Island Park, ID
- Average pressure in September: 29.99"Hg
The month with the highest atmospheric pressure is January (30.26"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Island Park, ID
- Average wind speed in September: 5.5mph
The windiest month (with the highest average wind speed) is June (6.3mph).
The calmest month (with the lowest average wind speed) is January (4.4mph).
Average humidity in September
Island Park, ID
- Average humidity in September: 53%
The months with the highest relative humidity are January and February (94%).
The month with the lowest relative humidity is August (47%).
Average rainfall in September
Island Park, ID
- Average rainfall in September: 1.14"
The wettest month (with the highest rainfall) is February (2.64").
The driest month (with the least rainfall) is July (0.47").
Average rainfall days in September
Island Park, ID
- Average rainfall days in September: 7.9 days
The month with the highest number of rainy days is May (17 days).
The month with the least rainy days is January (3.8 days).
Average snowfall in September
Island Park, ID
- Average snowfall in September: 1.69"
The month with the highest snowfall is January (19.84").
The month with the least snowfall is August (0").
Average snowfall days in September
Island Park, ID
- Average snowfall days in September: 1.2 days
The month with the highest number of snowfall days is December (23 days).
The month with the least snowfall days is August (0 days).
Average daylight in September /
Average sunshine in September
Island Park, 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 54min
The month with the most sunshine is July (Average sunshine: 12h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days in September
Island Park, ID
- Average sunshine days in September: 19.3 days
The month with the most sunshine days is July (21.2 days).
The month with the least sunshine days is February (5.9 days).
Average UV index in September
Island Park, 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, November and December (UV index 1).
Average cloud cover in September
Island Park, ID
- Average cloud cover in September: 19
The month with the most cloud cover is February (Cloud cover 67).
The month with the least cloud cover is July (Cloud cover 13).
Average visibility in September
Island Park, 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 and December (3mi).
