September weather forecastDee, OR
September
Weather in September
The first month of the autumn, September, is also an agreeable month in Dee, Oregon, with an average temperature fluctuating between 47.1°F (8.4°C) and 68.9°F (20.5°C).Temperature
Transition into September marks a drop in the average high-temperature, moving from a moderately hot 78.4°F (25.8°C) in August to an agreeable 68.9°F (20.5°C). Dee, in the heat of September, registers a significant plunge to a mean of 47.1°F (8.4°C) during the nights.Humidity
In September, the average relative humidity is 66%.Rainfall
In Dee, in September, during 9.2 rainfall days, 1.14" (29mm) of precipitation is typically accumulated. Throughout the year, there are 159.7 rainfall days, and 31.42" (798mm) of precipitation is accumulated.Snowfall
April through October are months without snowfall.Daylight
In September, the average length of the day is 12h and 31min.On the first day of the month, sunrise is at 6:28 am and sunset at 7:43 pm. On the last day of September, sunrise is at 7:04 am and sunset at 6:47 pm PDT.
Sunshine
In Dee, the average sunshine in September is 9.9h.UV index
The average daily maximum UV index in September is 3. A UV Index estimate of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for average individuals.Note: An average UV index of 3 in September transforms into this advice:
Undertake precautions - It is suggested to shield oneself from sunburn. Sun's radiation is most powerful around mid-day, so it's best to limit outdoor activities during this time. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Dee, OR
- Average high temperature in September: 68.9°F
The warmest month (with the highest average high temperature) is August (78.4°F).
The month with the lowest average high temperature is December (36°F).
- Average low temperature in September: 47.1°F
The month with the highest average low temperature is August (51.4°F).
The coldest month (with the lowest average low temperature) is December (27°F).
Average pressure in September
Dee, OR
- Average pressure in September: 29.99"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is August (29.97"Hg).
Average wind speed in September
Dee, OR
- Average wind speed in September: 5mph
The windiest month (with the highest average wind speed) is June (6.1mph).
The calmest month (with the lowest average wind speed) is October (4.8mph).
Average humidity in September
Dee, OR
- Average humidity in September: 66%
The months with the highest relative humidity are February and December (88%).
The month with the lowest relative humidity is July (59%).
Average rainfall in September
Dee, OR
- Average rainfall in September: 1.14"
The wettest month (with the highest rainfall) is January (5.67").
The driest month (with the least rainfall) is July (0.28").
Average rainfall days in September
Dee, OR
- Average rainfall days in September: 9.2 days
The month with the highest number of rainy days is March (20 days).
The month with the least rainy days is August (4.2 days).
Average snowfall in September
Dee, OR
- Average snowfall in September: 0"
The month with the highest snowfall is February (4.76").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Dee, OR
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is December (4.1 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Dee, OR
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 36min).
The month with the shortest days is December (Average daylight: 8h and 48min).
- Average sunshine in September: 9h and 54min
The month with the most sunshine is July (Average sunshine: 11h and 42min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in September
Dee, OR
- Average sunshine days in September: 18.7 days
The month with the most sunshine days is July (25.4 days).
The month with the least sunshine days is March (8.4 days).
Average UV index in September
Dee, OR
- Average UV index in September: 3
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February and November (UV index 1).
Average cloud cover in September
Dee, OR
- Average cloud cover in September: 29
The months with the most cloud cover are January and February (Cloud cover 64).
The months with the least cloud cover are July and August (Cloud cover 17).
Average visibility in September
Dee, OR
- Average visibility in September: 6mi
The months with the highest visibility are May, June, July, August and September (6mi).
The months with the lowest visibility are January, February and December (4mi).





