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
The shift from August to September includes a small decrease in the average high-temperature, from a pleasant 73°F (22.8°C) to a refreshing 67.1°F (19.5°C). John Sam Lake, during September nights, observes an average temperature of 50°F (10°C).Humidity
In September, the average relative humidity in John Sam Lake is 77%.Rainfall
In September, the rain falls for 12.3 days. Throughout September, 1.77" (45mm) of precipitation is accumulated. Throughout the year, there are 179.1 rainfall days, and 29.57" (751mm) of precipitation is accumulated.Snowfall
May through October are months without snowfall.Daylight
The average length of the day in September in John Sam Lake is 12h and 33min.On the first day of the month, sunrise is at 6:28 am and sunset at 7:49 pm. On the last day of September, sunrise is at 7:08 am and sunset at 6:49 pm PDT.
Sunshine
In September, the average sunshine is 9.2h.UV index
In John Sam Lake, Washington, the average daily maximum UV index in September is 3. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for the average person.Note: During September, 3 as the daily maximum UV index converts into the following advice:
Exercise caution. Those with pale skin may experience burns in less than half an hour. Sun's radiation is most powerful around mid-day, so it's best to limit outdoor activities during this time. Sunglasses providing both UVA and UVB protection are non-negotiable on sunlit days.
Frequently asked questions
What is the average September temperature in John Sam Lake?
What is the average humidity in September in John Sam Lake?
How much does it rain in John Sam Lake in September?
When it does not snow in John Sam Lake?
What is the average length of the day in September in John Sam Lake?
When are sunrise and sunset in September in John Sam Lake?
How many hours of sunshine does John Sam Lake have in September?
What is the UV index intensity in September in John Sam Lake?
Average temperature in September
John Sam Lake, WA
- Average high temperature in September: 67.1°F
The warmest month (with the highest average high temperature) is August (73°F).
The month with the lowest average high temperature is December (42.3°F).
- Average low temperature in September: 50°F
The month with the highest average low temperature is August (52.5°F).
The coldest month (with the lowest average low temperature) is December (34.7°F).
Average pressure in September
John Sam Lake, WA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The month with the lowest atmospheric pressure is August (30"Hg).
Average wind speed in September
John Sam Lake, WA
- Average wind speed in September: 4mph
The windiest months (with the highest average wind speed) are March and November (5.8mph).
The calmest month (with the lowest average wind speed) is August (3.5mph).
Average humidity in September
John Sam Lake, WA
- Average humidity in September: 77%
The months with the highest relative humidity are January and December (85%).
The month with the lowest relative humidity is July (73%).
Average rainfall in September
John Sam Lake, WA
- Average rainfall in September: 1.77"
The wettest month (with the highest rainfall) is November (4.06").
The driest month (with the least rainfall) is July (0.47").
Average rainfall days in September
John Sam Lake, WA
- Average rainfall days in September: 12.3 days
The month with the highest number of rainy days is March (19.8 days).
The month with the least rainy days is August (6.1 days).
Average snowfall in September
John Sam Lake, WA
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.68").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
John Sam Lake, WA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (3.1 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
John Sam Lake, WA
- Average daylight in September: 12h and 4min
The month with the longest days is June (Average daylight: 16h and 0min).
The month with the shortest days is December (Average daylight: 8h and 24min).
- Average sunshine in September: 9h and 1min
The month with the most sunshine is August (Average sunshine: 10h and 36min).
The months with the least sunshine are January and December (Average sunshine: 4h and 12min).
Average sunshine days in September
John Sam Lake, WA
- Average sunshine days in September: 16.1 days
The month with the most sunshine days is August (23.1 days).
The months with the least sunshine days are February and November (8.6 days).
Average UV index in September
John Sam Lake, WA
- Average UV index in September: 3
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
John Sam Lake, WA
- Average cloud cover in September: 34
The month with the most cloud cover is December (Cloud cover 57).
The month with the least cloud cover is August (Cloud cover 26).
Average visibility in September
John Sam Lake, WA
- Average visibility in September: 6mi
The months with the highest visibility are March, April, May, June, July, August, September and October (6mi).
The months with the lowest visibility are January, February, November and December (5mi).
John Sam Lake, Washington, USA
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