Temperatures in July
It's warm in July in Mercer Island with an average temperature of 26°C. Temperatures this month range from a low of 23°C to a high of 31°C. At night, you can expect temperatures between 15°C and 18°C.
Max and Min Temperatures per Day
This chart shows the daily maximum and minimum temperatures in degrees Celsius for Mercer Island in July. The red line indicates the max temperatures, and the blue line shows the minimums.
Start of July
The month of July starts in Mercer Island with warm temperatures, averaging around 26°C during the day and nights close to 16°C. There’s little chance of precipitation. The weather is mostly sunny and dry.
Since temperatures can differ between day and night, it’s a good idea to dress in layers.
Mid-July
By mid-July, the average daytime temperature rises to around 27°C, with nights close to 16°C. Not much precipitation expected during this period. It’s mostly dry with sunshine.
Temperatures vary between day and night, so it’s smart to wear layers.
End of July
By the end of July, the average daytime temperature in Mercer Island will be around 28°C, with nights close to 17°C. Barely any chance of precipitation. The weather will mostly be dry with lots of sunshine.
As it gets cooler in the evening, it’s best to wear layers.
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Precipitation in July
According to weather history, there is only 9,4 mm of precipitation in July. The wind speed is around 3 Bft, mostly coming from the West.
The average chance of precipitation is only 5% in July.
Precipitation Chance
This chart shows the daily precipitation chance (in percentages) in July for Mercer Island. 0% means it never rained on that day in the past 10 years, and 100% means it rained every day. All values in between represent the average chance of precipitation on that day.
Mercer Island in July |
London | ||
|---|---|---|---|
 Average Temperature |
26°C | 23°C | |
 High Temp |
31°C | 27°C | |
| Low Temp |
23°C | 21°C | |
 Total Precipitation |
9,4 mm | 52 mm | |
| Rainy Days |
2 days | 9 days | |
June
UV index
The UV index is a maximum of 8 this month. That's a very high value on the intensity scale of 1 to 11. Unprotected skin can burn within 10-15 minutes.
Is July a good time to visit Mercer Island?
Want nice weather? Then July is a great time to be in Mercer Island. You’ll have pleasant temperatures and not too much rain this month.
Temperature records for Mercer Island in July
With 36°C, Mercer Island hit the highest temperature in the last 10 years in July 2015. The lowest daytime temperature in this month was 15°C in 2022. The extreme night temperatures ranged from a low of 10°C to a high of 21°C.
Check out the climate of Mercer Island for all months and discover the best travel time
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Daily Temperature in July in Mercer Island
This chart shows the average daily temperatures, both day and night, for each day in July in Mercer Island, measured in degrees Celsius. The red line represents the maximum temperatures, while the blue line shows the minimums. The days of the month are displayed at the bottom of the chart. The data, based on historical observations, gives an overview of the average daily temperatures during this month.
Daily Precipitation in July in Mercer Island
The chart below shows the average daily precipitation in July for Mercer Island, measured in millimetres over the past years. Precipitation is always measured as water, even if it’s snow or hail. The days of the month are shown at the bottom of the chart.
A low average precipitation means that the chance of rain on that day is usually small, while a higher average suggests that rain is more likely. But it’s still an average, so each day can be different. Based on historical weather data for July, you can expect around 2 days of rain in Mercer Island.
Daily UV Index in July in Mercer Island
This chart shows the average daily UV index in July in Mercer Island, with the UV index ranging from 0 to a maximum of 11. The bottom of the chart shows the days of the month. Based on historical data, this chart provides an idea of the daily UV radiation levels you can expect.
Temperature in July in Mercer Island Over the Years
This chart shows the average temperature in July in Mercer Island, measured in degrees Celsius, over the past years.
Total Precipitation in July in Mercer Island Over the Years
This chart shows the average precipitation in July in Mercer Island, measured in millimetres over the past years. Precipitation is always measured as water, even if it’s snow or hail.
Daily climate in July for Mercer Island
Click on a specific day in July for detailed info on the typical weather on that day in Mercer Island. Check out the historical temperatures and precipitation over the past 10 years on this day.
Weather experiences in July in Mercer Island
Have you been to Mercer Island in July?
Share your weather experience in July in Mercer Island.
Average Weather in Mercer Island by Month
Click on a month below to see detailed weather info for Mercer Island. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.
Or check out the climate of Mercer Island for all months at once
