Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
In the transition to September, Rosalia observes a drop in the average high-temperature, moving from a warm 83.8°F (28.8°C) in August to a pleasant 72.9°F (22.7°C). During the month of September, Rosalia experiences a steady low-temperature average of 53.2°F (11.8°C).Humidity
In September, the average relative humidity in Rosalia is 45%.Rainfall
In Rosalia, Washington, in September, it is raining for 5.6 days, with typically 0.24" (6mm) of accumulated precipitation. Throughout the year, in Rosalia, there are 84.3 rainfall days, and 7.24" (184mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, September, November and December. September is the first month it typically snows in Rosalia. Throughout September, in the average 0.1 snowfall days, it receives 0.04" (1mm) of snow. In Rosalia, during the entire year, snow falls for 32.5 days and aggregates up to 14.09" (358mm) of snow.Daylight
In September, the average length of the day is 12h and 32min.On the first day of the month, sunrise is at 6:09 am and sunset at 7:28 pm. On the last day of September, in Rosalia, sunrise is at 6:48 am and sunset at 6:30 pm PDT.
Sunshine
In September, the average sunshine is 10.4h.UV index
In Rosalia, the average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for the average person.Note: The UV index of 4 in September translates into these instructions:
Prioritize safety - Recommendations to avert sunburn are shared. Direct exposure to the Sun's intense radiation around midday should be avoided for health reasons. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear. Notice this! Nearly double the intensity of the Sun's UV radiation can be caused by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the usual temperature for Rosalia in September?
What is the average humidity in September?
How many days does it rain in September?
When does it start to snow?
How many hours of daylight does Rosalia have in September?
When are sunrise and sunset in September?
How long on average sun shines in September?
What is the UV index reading in September?
Average temperature in September
Rosalia, WA
- Average high temperature in September: 72.9°F
The warmest month (with the highest average high temperature) is July (84.4°F).
The month with the lowest average high temperature is December (33.1°F).
- Average low temperature in September: 53.2°F
The month with the highest average low temperature is August (61.3°F).
The coldest month (with the lowest average low temperature) is December (23.9°F).
Average pressure in September
Rosalia, WA
- Average pressure in September: 29.95"Hg
The month with the highest atmospheric pressure is January (30.19"Hg).
The month with the lowest atmospheric pressure is August (29.9"Hg).
Average wind speed in September
Rosalia, WA
- Average wind speed in September: 7mph
The windiest month (with the highest average wind speed) is March (8.8mph).
The calmest month (with the lowest average wind speed) is August (6.6mph).
Average humidity in September
Rosalia, WA
- Average humidity in September: 45%
The month with the highest relative humidity is January (87%).
The month with the lowest relative humidity is August (36%).
Average rainfall in September
Rosalia, WA
- Average rainfall in September: 0.24"
The wettest months (with the highest rainfall) are January and May (0.91").
The driest month (with the least rainfall) is July (0.16").
Average rainfall days in September
Rosalia, WA
- Average rainfall days in September: 5.6 days
The month with the highest number of rainy days is March (10.1 days).
The month with the least rainy days is July (3.5 days).
Average snowfall in September
Rosalia, WA
- Average snowfall in September: 0.04"
The month with the highest snowfall is February (3.82").
The months with the least snowfall are June, July, August and October (0").
Average snowfall days in September
Rosalia, WA
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is December (9.3 days).
The months with the least snowfall days are June, July, August and October (0 days).
Average daylight in September /
Average sunshine in September
Rosalia, WA
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 36min).
- Average sunshine in September: 10h and 2min
The month with the most sunshine is August (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 4h and 18min).
Average sunshine days in September
Rosalia, WA
- Average sunshine days in September: 23.6 days
The month with the most sunshine days is July (26.6 days).
The month with the least sunshine days is February (15.9 days).
Average UV index in September
Rosalia, WA
- Average UV index in September: 4
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Rosalia, WA
- Average cloud cover in September: 19
The months with the most cloud cover are January and December (Cloud cover 55).
The month with the least cloud cover is July (Cloud cover 11).
Average visibility in September
Rosalia, WA
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January and December (5mi).
Rosalia, Washington, USA
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