September weather forecastAltamont, OR
September
Weather in September
The first month of the autumn, September, is also an agreeable month in Altamont, Oregon, with an average temperature fluctuating between 72.7°F (22.6°C) and 43.7°F (6.5°C).Temperature
Altamont's progression into September involves a gentle drop in the average high-temperature, from a moderately hot 80.8°F (27.1°C) in August to an agreeable 72.7°F (22.6°C). September's nights exhibit a sharp contrast from day highs, with an average temperature of 43.7°F (6.5°C).Humidity
The average relative humidity in September is 53%.Rainfall
In Altamont, during September, the rain falls for 4.1 days and regularly aggregates up to 0.43" (11mm) of precipitation. In Altamont, during the entire year, the rain falls for 100.4 days and collects up to 13.15" (334mm) of precipitation.Snowfall
January through June, 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 0.12" (3mm) of snow. Throughout the year, there are 70.5 snowfall days, and 42.52" (1080mm) of snow is accumulated.Daylight
In Altamont, the average length of the day in September is 12h and 28min.On the first day of September, sunrise is at 6:33 am and sunset at 7:40 pm. On the last day of the month, sunrise is at 7:03 am and sunset at 6:49 pm PDT.
Sunshine
The average sunshine in September is 11h.UV index
In Altamont, the average daily maximum UV index in September is 3. A UV Index reading of 3 to 5 represents a medium health hazard from unprotected exposure to Sun's UV rays for the average person.Note: The maximum daily UV index of 3 in September converts into the following recommendations:
Take care. Persons with lighter skin might suffer burns in less than 30 minutes. Considering the strength of solar radiation at midday, one should avoid direct Sun exposure. During bright days, sunglasses that offer UVA and UVB defense are recommended. Be watchful! The reflection of snow can enhance the intensity of the Sun's UV radiation nearly double.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Altamont, OR
- Average high temperature in September: 72.7°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is December (36.9°F).
- Average low temperature in September: 43.7°F
The month with the highest average low temperature is July (48.6°F).
The coldest month (with the lowest average low temperature) is December (25.2°F).
Average pressure in September
Altamont, OR
- Average pressure in September: 29.98"Hg
The month with the highest atmospheric pressure is January (30.18"Hg).
The month with the lowest atmospheric pressure is August (29.96"Hg).
Average wind speed in September
Altamont, OR
- Average wind speed in September: 5mph
The windiest months (with the highest average wind speed) are March and April (6.3mph).
The calmest months (with the lowest average wind speed) are August and September (5mph).
Average humidity in September
Altamont, OR
- Average humidity in September: 53%
The month with the highest relative humidity is January (84%).
The month with the lowest relative humidity is August (49%).
Average rainfall in September
Altamont, OR
- Average rainfall in September: 0.43"
The wettest month (with the highest rainfall) is December (2.09").
The driest month (with the least rainfall) is July (0.2").
Average rainfall days in September
Altamont, OR
- Average rainfall days in September: 4.1 days
The month with the highest number of rainy days is April (13.1 days).
The month with the least rainy days is August (3.6 days).
Average snowfall in September
Altamont, OR
- Average snowfall in September: 0.12"
The month with the highest snowfall is December (10.63").
The months with the least snowfall are July and August (0").
Average snowfall days in September
Altamont, OR
- 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 July and August (0 days).
Average daylight in September /
Average sunshine in September
Altamont, OR
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in September: 11h and 0min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is January (Average sunshine: 5h and 18min).
Average sunshine days in September
Altamont, OR
- Average sunshine days in September: 23.7 days
The month with the most sunshine days is August (24.9 days).
The month with the least sunshine days is March (10.6 days).
Average UV index in September
Altamont, OR
- Average UV index in September: 3
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is February (UV index 1).
Average cloud cover in September
Altamont, OR
- Average cloud cover in September: 14
The month with the most cloud cover is December (Cloud cover 46).
The month with the least cloud cover is July (Cloud cover 8).
Average visibility in September
Altamont, OR
- Average visibility in September: 6mi
The months with the highest visibility are April, May, June, July, August, September, October and November (6mi).
The month with the lowest visibility is January (4mi).
