September weather forecastLummi Island, WA
September
Weather in September
The first month of the autumn, September, is also an enjoyable month in Lummi Island, Washington, with an average temperature ranging between min 50.9°F (10.5°C) and max 65.3°F (18.5°C).Temperature
In Lummi Island, the average high-temperature in September slightly decreases from a pleasant 71.1°F (21.7°C) in August to an enjoyable 65.3°F (18.5°C). During the nights in September, Lummi Island observes an average low-temperature of 50.9°F (10.5°C).Humidity
In Lummi Island, the average relative humidity in September is 79%.Rainfall
In Lummi Island, in September, it is raining for 13.4 days, with typically 2.52" (64mm) of accumulated precipitation. In Lummi Island, during the entire year, the rain falls for 178.6 days and collects up to 37.32" (948mm) of precipitation.Snowfall
In Lummi Island, snow does not fall in May through October.Daylight
In Lummi Island, the average length of the day in September is 12h and 34min.On the first day of the month, sunrise is at 6:29 am and sunset at 7:51 pm. On the last day of September, sunrise is at 7:10 am and sunset at 6:50 pm PDT.
Sunshine
In Lummi Island, the average sunshine in September is 9.3h.UV index
In September, the average daily maximum UV index is 4. A UV Index value of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV rays for the ordinary person.Note: A maximum daily UV index of 4 during September morphs into the following directions:
Take necessary precautions - Defending against sun damage is advocated. Sun's radiation is most powerful around mid-day, so it's best to limit outdoor activities during this time. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Lummi Island, WA
- Average high temperature in September: 65.3°F
The warmest month (with the highest average high temperature) is August (71.1°F).
The month with the lowest average high temperature is December (41.9°F).
- Average low temperature in September: 50.9°F
The month with the highest average low temperature is August (53.8°F).
The coldest month (with the lowest average low temperature) is February (35.2°F).
Average pressure in September
Lummi Island, WA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.08"Hg).
The month with the lowest atmospheric pressure is March (30"Hg).
Average wind speed in September
Lummi Island, WA
- Average wind speed in September: 3.9mph
The windiest month (with the highest average wind speed) is November (6.2mph).
The calmest month (with the lowest average wind speed) is August (3.7mph).
Average humidity in September
Lummi Island, WA
- Average humidity in September: 79%
The month with the highest relative humidity is January (84%).
The month with the lowest relative humidity is July (74%).
Average rainfall in September
Lummi Island, WA
- Average rainfall in September: 2.52"
The wettest month (with the highest rainfall) is November (5.71").
The driest month (with the least rainfall) is July (0.67").
Average rainfall days in September
Lummi Island, WA
- Average rainfall days in September: 13.4 days
The month with the highest number of rainy days is November (20.1 days).
The month with the least rainy days is August (7.3 days).
Average snowfall in September
Lummi Island, WA
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.56").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Lummi Island, WA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (3.8 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
Lummi Island, WA
- Average daylight in September: 12h and 36min
The month with the longest days is June (Average daylight: 16h and 6min).
The month with the shortest days is December (Average daylight: 8h and 24min).
- Average sunshine in September: 9h and 18min
The months with the most sunshine are July and August (Average sunshine: 10h and 30min).
The months with the least sunshine are January and December (Average sunshine: 4h and 12min).
Average sunshine days in September
Lummi Island, WA
- Average sunshine days in September: 15.3 days
The month with the most sunshine days is August (21.9 days).
The month with the least sunshine days is November (8.5 days).
Average UV index in September
Lummi Island, WA
- Average UV index in September: 4
The months with the highest UV index are June and 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
Lummi Island, WA
- Average cloud cover in September: 33
The months with the most cloud cover are January and December (Cloud cover 56).
The month with the least cloud cover is August (Cloud cover 25).
Average visibility in September
Lummi Island, WA
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).
