September weather forecastKirkland, WA
September
Weather in September
September marks an emphatic shift towards autumn with a notable dip in temperature from the summer livelihood. Specific climatic patterns mimic August, with a steady decline in warmth observed as the month progresses. Although summer relinquishes its hold, September continues to benefit from long hours of daylight and warm weather. Despite the minor decrease in temperature, the handsome blend of summer and autumn sets a captivating tone throughout the city.Temperature
The arrival of September suggests a slight decrease in the average high-temperature, moving from a moderately hot 75.9°F (24.4°C) in August to a pleasant 69.3°F (20.7°C). Throughout the month of September, Kirkland witnesses an average temperature of 50.2°F (10.1°C).Humidity
The average relative humidity in September is 75%.Rainfall
In September, in Kirkland, the rain falls for 10.9 days. Throughout September, 1.3" (33mm) of precipitation is accumulated. Throughout the year, in Kirkland, there are 175.1 rainfall days, and 28.58" (726mm) of precipitation is accumulated.Snowfall
In Kirkland, snow does not fall in May through October.Daylight
In September, the average length of the day is 12h and 33min.On the first day of the month, sunrise is at 6:28 am and sunset at 7:48 pm. On the last day of September, sunrise is at 7:07 am and sunset at 6:49 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 of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for ordinary individuals.Note: The maximum daily UV index of 4 in September converts into the following recommendations:
Prioritize safety - The need to safeguard skin and eyes from harm is emphasized. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Kirkland, WA
- Average high temperature in September: 69.3°F
The warmest month (with the highest average high temperature) is August (75.9°F).
The month with the lowest average high temperature is December (42.8°F).
- Average low temperature in September: 50.2°F
The month with the highest average low temperature is August (53.2°F).
The coldest month (with the lowest average low temperature) is December (34.7°F).
Average pressure in September
Kirkland, WA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is August (30"Hg).
Average wind speed in September
Kirkland, WA
- Average wind speed in September: 3.8mph
The windiest months (with the highest average wind speed) are January and March (5.2mph).
The calmest month (with the lowest average wind speed) is August (3.4mph).
Average humidity in September
Kirkland, WA
- Average humidity in September: 75%
The month with the highest relative humidity is January (85%).
The month with the lowest relative humidity is July (70%).
Average rainfall in September
Kirkland, WA
- Average rainfall in September: 1.3"
The wettest month (with the highest rainfall) is December (4.21").
The driest month (with the least rainfall) is July (0.43").
Average rainfall days in September
Kirkland, WA
- Average rainfall days in September: 10.9 days
The month with the highest number of rainy days is March (19.9 days).
The month with the least rainy days is August (6.1 days).
Average snowfall in September
Kirkland, WA
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.95").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Kirkland, WA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (3.9 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
Kirkland, WA
- Average daylight in September: 12h and 30min
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 30min).
- Average sunshine in September: 9h and 24min
The month with the most sunshine is August (Average sunshine: 10h and 42min).
The months with the least sunshine are January and December (Average sunshine: 4h and 24min).
Average sunshine days in September
Kirkland, WA
- Average sunshine days in September: 16.5 days
The month with the most sunshine days is August (22.8 days).
The month with the least sunshine days is March (8.9 days).
Average UV index in September
Kirkland, WA
- Average UV index in September: 4
The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Kirkland, WA
- Average cloud cover in September: 33
The months with the most cloud cover are January and December (Cloud cover 55).
The month with the least cloud cover is August (Cloud cover 25).
Average visibility in September
Kirkland, WA
- Average visibility in September: 6mi
The months with the highest visibility are April, May, June, July, August, September and October (6mi).
The months with the lowest visibility are January, February, March, November and December (5mi).
