September weather forecastMartha Lake, WA
September
Weather in September
The first month of the autumn, September, is still a refreshing month in Martha Lake, Washington, with an average temperature ranging between max 67.1°F (19.5°C) and min 51.4°F (10.8°C).Temperature
A mild drop in Martha Lake's average high-temperature is observed in September, transitioning from a pleasant 72.7°F (22.6°C) in August to a refreshing 67.1°F (19.5°C). Martha Lake's September nights cool down to an average low-temperature of 51.4°F (10.8°C).Humidity
In Martha Lake, the average relative humidity in September is 77%.Rainfall
In Martha Lake, Washington, during September, the rain falls for 11.3 days and regularly aggregates up to 1.5" (38mm) of precipitation. In Martha Lake, during the entire year, the rain falls for 173.1 days and collects up to 26.02" (661mm) of precipitation.Snowfall
In Martha Lake, snow does not fall in May through October.Daylight
The average length of the day in September is 12h and 33min.On the first day of September, sunrise is at 6:28 am and sunset at 7:48 pm. On the last day of the month, sunrise is at 7:07 am and sunset at 6:49 pm PDT.
Sunshine
In September, the average sunshine is 9.4h.UV index
In September, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a medium vulnerability from unprotected exposure to Sun's UV rays for the ordinary person.Note: In September, the maximum UV index of 4 suggests these recommendations:
Take precautions - Protection against sunburn is recommended. To protect against the Sun's most potent rays, avoid direct exposure around midday. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Martha Lake, WA
- Average high temperature in September: 67.1°F
The warmest month (with the highest average high temperature) is August (72.7°F).
The month with the lowest average high temperature is December (42.6°F).
- Average low temperature in September: 51.4°F
The month with the highest average low temperature is August (54°F).
The coldest month (with the lowest average low temperature) is December (35.4°F).
Average pressure in September
Martha Lake, WA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The months with the lowest atmospheric pressure are March, August and September (30.01"Hg).
Average wind speed in September
Martha Lake, WA
- Average wind speed in September: 4.2mph
The windiest month (with the highest average wind speed) is November (6.2mph).
The calmest month (with the lowest average wind speed) is August (3.6mph).
Average humidity in September
Martha Lake, WA
- Average humidity in September: 77%
The months with the highest relative humidity are February and December (84%).
The month with the lowest relative humidity is July (72%).
Average rainfall in September
Martha Lake, WA
- Average rainfall in September: 1.5"
The wettest month (with the highest rainfall) is December (3.54").
The driest month (with the least rainfall) is July (0.43").
Average rainfall days in September
Martha Lake, WA
- Average rainfall days in September: 11.3 days
The month with the highest number of rainy days is March (19.8 days).
The month with the least rainy days is August (6.3 days).
Average snowfall in September
Martha Lake, WA
- Average snowfall in September: 0"
The month with the highest snowfall is February (4.61").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Martha Lake, WA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (5.2 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
Martha Lake, WA
- Average daylight in September: 12h and 36min
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 30min).
- Average sunshine in September: 9h and 24min
The month with the most sunshine is August (Average sunshine: 10h and 42min).
The month with the least sunshine is January (Average sunshine: 4h and 24min).
Average sunshine days in September
Martha Lake, WA
- Average sunshine days in September: 16.5 days
The month with the most sunshine days is August (22.6 days).
The month with the least sunshine days is November (9.1 days).
Average UV index in September
Martha Lake, 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
Martha Lake, WA
- Average cloud cover in September: 32
The month with the most cloud cover is December (Cloud cover 54).
The month with the least cloud cover is August (Cloud cover 25).
Average visibility in September
Martha Lake, 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).





