September weather forecastRichland, OR
September
Weather in September
The first month of the autumn, September, is also an agreeable month in Richland, Oregon, with an average temperature varying between 47.3°F (8.5°C) and 71.2°F (21.8°C).Temperature
The onset of September is marked by a decrease in temperature, transitioning from a moderately hot 81.3°F (27.4°C) in August to an agreeable 71.2°F (21.8°C). In September, the temperature sees a substantial plunge from daytime highs to a low average of 47.3°F (8.5°C).Humidity
The average relative humidity in September is 47%.Rainfall
In Richland, Oregon, in September, it is raining for 6.5 days, with typically 0.43" (11mm) of accumulated precipitation. Throughout the year, in Richland, there are 113.5 rainfall days, and 12.56" (319mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall.Daylight
In Richland, the average length of the day in September is 12h and 30min.On the first day of the month, sunrise is at 6:12 am and sunset at 7:24 pm. On the last day of September, sunrise is at 6:46 am and sunset at 6:30 pm PDT.
Sunshine
In September, the average sunshine is 10.7h.UV index
In September, the average daily maximum UV index is 4. A UV Index of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV radiation for the ordinary person.Note: A maximum daily UV index of 4 during September morphs into the following directions:
Undertake precautions - Guarding against sun damage is counselled. Considering the harmful UV rays from the Sun during midday, it's essential to reduce exposure. To cut down UV radiation exposure by about half, sport a wide-brim hat. Take heed! The reflection of snow can intensify 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
Richland, OR
- Average high temperature in September: 71.2°F
The warmest month (with the highest average high temperature) is July (81.7°F).
The month with the lowest average high temperature is December (30.7°F).
- Average low temperature in September: 47.3°F
The month with the highest average low temperature is August (53.8°F).
The coldest month (with the lowest average low temperature) is December (18.5°F).
Average pressure in September
Richland, OR
- Average pressure in September: 29.96"Hg
The month with the highest atmospheric pressure is January (30.22"Hg).
The month with the lowest atmospheric pressure is August (29.92"Hg).
Average wind speed in September
Richland, OR
- Average wind speed in September: 5.4mph
The windiest month (with the highest average wind speed) is April (6.2mph).
The calmest months (with the lowest average wind speed) are September and October (5.4mph).
Average humidity in September
Richland, OR
- Average humidity in September: 47%
The month with the highest relative humidity is January (88%).
The month with the lowest relative humidity is August (40%).
Average rainfall in September
Richland, OR
- Average rainfall in September: 0.43"
The wettest month (with the highest rainfall) is December (1.77").
The driest month (with the least rainfall) is August (0.31").
Average rainfall days in September
Richland, OR
- Average rainfall days in September: 6.5 days
The month with the highest number of rainy days is March (15.6 days).
The month with the least rainy days is August (4.4 days).
Average snowfall in September
Richland, OR
- Average snowfall in September: 0"
The month with the highest snowfall is December (10.59").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Richland, OR
- Average snowfall days in September: 0.2 days
The month with the highest number of snowfall days is December (14.7 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Richland, OR
- 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: 10h and 42min
The month with the most sunshine is August (Average sunshine: 12h and 6min).
The month with the least sunshine is January (Average sunshine: 4h and 48min).
Average sunshine days in September
Richland, OR
- Average sunshine days in September: 21.4 days
The month with the most sunshine days is July (22.7 days).
The months with the least sunshine days are February and March (11.3 days).
Average UV index in September
Richland, OR
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in September
Richland, OR
- Average cloud cover in September: 15
The month with the most cloud cover is February (Cloud cover 50).
The months with the least cloud cover are July and August (Cloud cover 9).
Average visibility in September
Richland, OR
- Average visibility in September: 6mi
The months with the highest visibility are April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January, February and December (4mi).
