September weather forecastBrownsville, OR
September
Weather in September
The first month of the autumn, September, is still a warm month in Brownsville, Oregon, with temperature in the range of an average high of 73.4°F (23°C) and an average low of 48.9°F (9.4°C).Temperature
September's arrival signals a moderate reduction in the average high-temperature, easing from a moderately hot 81.1°F (27.3°C) in August to a still warm 73.4°F (23°C). In September, the temperature registers a significant dip to an average of 48.9°F (9.4°C) at night.Humidity
In Brownsville, the average relative humidity in September is 71%.Rainfall
In Brownsville, in September, during 8.8 rainfall days, 1.5" (38mm) of precipitation is typically accumulated. Throughout the year, there are 163.3 rainfall days, and 29.92" (760mm) of precipitation is accumulated.Snowfall
In Brownsville, snow does not fall in April through October.Daylight
In September, the average length of the day is 12h and 30min.On the first day of September, sunrise is at 6:35 am and sunset at 7:47 pm. On the last day of the month, sunrise is at 7:09 am and sunset at 6:53 pm PDT.
Sunshine
In September, the average sunshine is 9.4h.UV index
The average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a medium health hazard from exposure to the Sun's UV rays for the average person.Note: The maximum daily UV index, 4 in September, converts into the following recommendations:
Be mindful. Individuals with a lighter skin tone may suffer burns in less than 30 minutes. To avoid the Sun's strongest rays, limit exposure around the mid-day period. Stay sun-safe with clothing that is both closely woven and worn loosely.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Brownsville, OR
- Average high temperature in September: 73.4°F
The warmest month (with the highest average high temperature) is August (81.1°F).
The month with the lowest average high temperature is December (45.3°F).
- Average low temperature in September: 48.9°F
The month with the highest average low temperature is August (51.8°F).
The coldest month (with the lowest average low temperature) is December (34.2°F).
Average pressure in September
Brownsville, OR
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.12"Hg).
The months with the lowest atmospheric pressure are August and September (30.01"Hg).
Average wind speed in September
Brownsville, OR
- Average wind speed in September: 4mph
The windiest months (with the highest average wind speed) are January and March (5.1mph).
The calmest month (with the lowest average wind speed) is August (3.9mph).
Average humidity in September
Brownsville, OR
- Average humidity in September: 71%
The months with the highest relative humidity are January, February, March and December (86%).
The month with the lowest relative humidity is August (66%).
Average rainfall in September
Brownsville, OR
- Average rainfall in September: 1.5"
The wettest month (with the highest rainfall) is December (4.41").
The driest month (with the least rainfall) is July (0.24").
Average rainfall days in September
Brownsville, OR
- Average rainfall days in September: 8.8 days
The month with the highest number of rainy days is March (20.1 days).
The months with the least rainy days are July and August (3.8 days).
Average snowfall in September
Brownsville, OR
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.13").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Brownsville, OR
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (2.5 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
Brownsville, 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: 9h and 24min
The month with the most sunshine is August (Average sunshine: 11h and 12min).
The month with the least sunshine is February (Average sunshine: 4h and 12min).
Average sunshine days in September
Brownsville, OR
- Average sunshine days in September: 19.3 days
The month with the most sunshine days is July (25.6 days).
The month with the least sunshine days is March (9.1 days).
Average UV index in September
Brownsville, OR
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Brownsville, OR
- Average cloud cover in September: 30
The month with the most cloud cover is February (Cloud cover 59).
The month with the least cloud cover is August (Cloud cover 20).
Average visibility in September
Brownsville, OR
- Average visibility in September: 6mi
The months with the highest visibility are July, August and September (6mi).
The month with the lowest visibility is February (4mi).





