Mercer Island Weather Forecast 15 Days, Weather in Mercer Island Today
Current weather conditions and 15 day weather forecast for Mercer Island, Washington, USA including weather daily high/low temperature, warnings, chance of precipitation, pressure, humidity/wind chill, rain risk, wind speed, cloud, pressure, and UV index.
Current weather conditions at Mercer Island
| 12 August 2026 Wednesday 23.9 ° C / 74.9°F  Clear |
Feels Like : 25.2 ° C / 77.4°F Humidity : % 50 Pressure : 1017 mb Wind Speed : 8.3 kmph / 5.1 miles from NNE  Visibility : 16.1 km Precipitation (rainfall) : 0 mm Cloud (%) : 0 |
15 day weather forecast for Mercer Island, WA, USA
Weather Forecast for next 15 Days for Mercer Island including weather warnings, temperature, rain, wind speed, cloud, snow, wind speed and wind direction, pressure and UV index.Here is weather for the next 15 days in Mercer Island, Washington state, US. To see the daily forecast, scroll to the table below.
| Date | Weather forecast | Low temperature | High temperature | Avg. temperature | Humidity | Chance of rain | UV Index | Sun Position | Moon Position | |
|---|---|---|---|---|---|---|---|---|---|---|
| 11 August 2026 Tuesday | Sunny |
13.5 ° C (56.3°F) |
28.2 ° C (82.8°F) |
20.1 ° C (68.1°F) |
% 63 | 4% | 7.3 | Sunrise:05:59 AM Sunset: 08:28 PM |
Moonrise:03:56 AM Moonset: 08:03 PM Moon Phase ( New Moon ) |
|
| 12 August 2026 Wednesday | Sunny |
14.4 ° C (57.9°F) |
25.7 ° C (78.3°F) |
19.8 ° C (67.6°F) |
% 66 | 6% | 4.9 | Sunrise:06:01 AM Sunset: 08:26 PM |
Moonrise:05:26 AM Moonset: 08:29 PM Moon Phase ( New Moon ) |
|
| 13 August 2026 Thursday | Sunny |
12.6 ° C (54.8°F) |
28.9 ° C (84°F) |
20.3 ° C (68.6°F) |
% 63 | 4% | 3.6 | Sunrise:06:02 AM Sunset: 08:25 PM |
Moonrise:06:55 AM Moonset: 08:50 PM Moon Phase ( New Moon ) |
|
| 14 August 2026 Friday |  Patchy rain nearby |
14.5 ° C (58°F) |
29.8 ° C (85.7°F) |
20.2 ° C (68.4°F) |
% 69 | 42% | 2.8 | Sunrise:06:03 AM Sunset: 08:23 PM |
Moonrise:08:21 AM Moonset: 09:08 PM Moon Phase ( Waxing Crescent ) |
|
| 15 August 2026 Saturday | Sunny |
13.1 ° C (55.6°F) |
29 ° C (84.1°F) |
19.9 ° C (67.8°F) |
% 64 | 17% | 2 | Sunrise:06:04 AM Sunset: 08:21 PM |
Moonrise:09:44 AM Moonset: 09:26 PM Moon Phase ( Waxing Crescent ) |
|
| 16 August 2026 Sunday | Sunny |
12.4 ° C (54.4°F) |
27.9 ° C (82.1°F) |
19.4 ° C (66.9°F) |
% 62 | 5% | 7 | Sunrise:06:06 AM Sunset: 08:20 PM |
Moonrise:11:04 AM Moonset: 09:44 PM Moon Phase ( Waxing Crescent ) |
|
| 17 August 2026 Monday | Sunny |
12.7 ° C (54.9°F) |
29.3 ° C (84.8°F) |
20.3 ° C (68.5°F) |
% 58 | 4% | 7 | Sunrise:06:07 AM Sunset: 08:18 PM |
Moonrise:12:23 PM Moonset: 10:05 PM Moon Phase ( Waxing Crescent ) |
|
| 18 August 2026 Tuesday |  Partly Cloudy |
15.9 ° C (60.6°F) |
29.3 ° C (84.7°F) |
21.5 ° C (70.6°F) |
% 48 | 3% | 7 | Sunrise:06:08 AM Sunset: 08:16 PM |
Moonrise:01:41 PM Moonset: 10:30 PM Moon Phase ( First Quarter ) |
|
| 19 August 2026 Wednesday | Sunny |
13.7 ° C (56.6°F) |
29 ° C (84.1°F) |
20.5 ° C (68.9°F) |
% 52 | 3% | 7 | Sunrise:06:10 AM Sunset: 08:14 PM |
Moonrise:02:55 PM Moonset: 11:01 PM Moon Phase ( First Quarter ) |
|
| 20 August 2026 Thursday | Sunny |
14.5 ° C (58.1°F) |
24.5 ° C (76.1°F) |
18.2 ° C (64.8°F) |
% 67 | 6% | 6 | Sunrise:06:11 AM Sunset: 08:12 PM |
Moonrise:04:04 PM Moonset: 11:41 PM Moon Phase ( First Quarter ) |
|
| 21 August 2026 Friday | Sunny |
12.5 ° C (54.5°F) |
27.5 ° C (81.5°F) |
19.3 ° C (66.7°F) |
% 66 | 5% | 7 | Sunrise:06:13 AM Sunset: 08:11 PM |
Moonrise:05:03 PM Moonset: Does not set today Moon Phase ( First Quarter ) |
|
| 22 August 2026 Saturday | Sunny |
13 ° C (55.4°F) |
30.3 ° C (86.5°F) |
20.8 ° C (69.5°F) |
% 59 | 3% | 8 | Sunrise:06:14 AM Sunset: 08:09 PM |
Moonrise:05:51 PM Moonset: 12:30 AM Moon Phase ( Waxing Gibbous ) |
|
| 23 August 2026 Sunday | Sunny |
15.4 ° C (59.7°F) |
30.5 ° C (87°F) |
21.6 ° C (71°F) |
% 56 | 3% | 8 | Sunrise:06:15 AM Sunset: 08:07 PM |
Moonrise:06:28 PM Moonset: 01:29 AM Moon Phase ( Waxing Gibbous ) |
|
| 24 August 2026 Monday | Sunny |
15.4 ° C (59.7°F) |
33 ° C (91.4°F) |
23.4 ° C (74°F) |
% 52 | 2% | 8 | Sunrise:06:17 AM Sunset: 08:05 PM |
Moonrise:06:57 PM Moonset: 02:34 AM Moon Phase ( Waxing Gibbous ) |
|
Add a link to your web page; copy and paste this html to your web page