October weather forecastMercer Island, WA
October
Weather in October
October, like September, is another refreshing autumn month in Mercer Island, Washington, with temperature in the range of an average low of 44.2°F (6.8°C) and an average high of 58.6°F (14.8°C).Temperature
Mercer Island in October demonstrates a small temperature transition, adjusting from an average high of an agreeable 70°F (21.1°C) in September to a refreshing 58.6°F (14.8°C). In Mercer Island, October is marked by an average low-temperature of 44.2°F (6.8°C).Humidity
In Mercer Island, the average relative humidity in October is 79%.Rainfall
In Mercer Island, during October, the rain falls for 10.5 days and regularly aggregates up to 1.1" (28mm) of precipitation. Throughout the year, in Mercer Island, there are 119.1 rainfall days, and 11.97" (304mm) of precipitation is accumulated.Snowfall
In Mercer Island, snow does not fall in April through October.Daylight
The average length of the day in October in Mercer Island is 10h and 50min.On the first day of the month, sunrise is at 7:09 am and sunset at 6:47 pm. On the last day of October, in Mercer Island, sunrise is at 7:52 am and sunset at 5:52 pm PDT.
Sunshine
In October, the average sunshine in Mercer Island is 5.5h.UV index
In Mercer Island, the average daily maximum UV index in October is 3. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for average individuals.Note: In October, a daily maximum UV index of 3 leads to the following instructions:
Preventative actions are necessary - Recommendations to ward off sunburn are given. To prevent harmful UV exposure, minimize direct contact with the Sun around midday. Enhance your sun protection with tightly woven, yet airy clothing.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in October
Mercer Island, WA
- Average high temperature in October: 58.6°F
The warmest month (with the highest average high temperature) is August (76.6°F).
The month with the lowest average high temperature is December (42.8°F).
- Average low temperature in October: 44.2°F
The month with the highest average low temperature is August (53.4°F).
The coldest month (with the lowest average low temperature) is February (34.5°F).
Average pressure in October
Mercer Island, WA
- Average pressure in October: 30.04"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 October
Mercer Island, WA
- Average wind speed in October: 4.2mph
The windiest month (with the highest average wind speed) is March (5.1mph).
The calmest month (with the lowest average wind speed) is August (3.4mph).
Average humidity in October
Mercer Island, WA
- Average humidity in October: 79%
The month with the highest relative humidity is January (85%).
The month with the lowest relative humidity is July (69%).
Average rainfall in October
Mercer Island, WA
- Average rainfall in October: 1.1"
The wettest month (with the highest rainfall) is December (2.01").
The driest month (with the least rainfall) is July (0.24").
Average rainfall days in October
Mercer Island, WA
- Average rainfall days in October: 10.5 days
The month with the highest number of rainy days is March (13.7 days).
The month with the least rainy days is August (4.1 days).
Average snowfall in October
Mercer Island, WA
- Average snowfall in October: 0"
The month with the highest snowfall is February (1.77").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in October
Mercer Island, WA
- Average snowfall days in October: 0 days
The month with the highest number of snowfall days is February (3 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in October /
Average sunshine in October
Mercer Island, WA
- Average daylight in October: 10h and 48min
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 October: 5h and 30min
The month with the most sunshine is August (Average sunshine: 10h and 42min).
The month with the least sunshine is December (Average sunshine: 4h and 12min).
Average sunshine days in October
Mercer Island, WA
- Average sunshine days in October: 18.6 days
The month with the most sunshine days is August (24.9 days).
The month with the least sunshine days is February (13.8 days).
Average UV index in October
Mercer Island, WA
- Average UV index in October: 3
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in October
Mercer Island, WA
- Average cloud cover in October: 42
The month with the most cloud cover is December (Cloud cover 56).
The month with the least cloud cover is August (Cloud cover 25).
Average visibility in October
Mercer Island, WA
- Average visibility in October: 5mi
The months with the highest visibility are May, June, July, August and September (6mi).
The months with the lowest visibility are January, February, March, April, October, November and December (5mi).
