August weather in Roslyn, WA
The average temperature in Roslyn in August is 63.0°F (49.8°F–76.1°F). Average precipitation: 0.87 inches.
August is a summer month in Roslyn, and is warmer than the annual average of 45.2°F. Daily temperatures swing about 26.3°F between overnight low and afternoon high. Daylight averages about 14h 3m. For travel, August is a comfortable month to visit.
Avg High
76.1°F
Avg Low
49.8°F
Precipitation
0.87 in
Daylight
14h 3m
August records in Roslyn
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| August 1 | 98.1°F (2022) | 45.0°F (2006) | 0.37 in (1934) |
| August 2 | 95.0°F (2017) | 46.0°F (2006) | 0.00 in (1905) |
| August 3 | 93.0°F (2017) | 37.9°F (2006) | 0.44 in (2014) |
| August 4 | 95.0°F (2017) | 39.0°F (2006) | 0.88 in (2021) |
| August 5 | 96.1°F (2017) | 41.0°F (2005) | 0.30 in (1933) |
| August 6 | 93.0°F (2012) | 45.0°F (2008) | 0.13 in (2023) |
| August 7 | 93.0°F (2017) | 46.0°F (2006) | 0.30 in (2004) |
| August 8 | 91.9°F (2022) | 37.9°F (2004) | 0.03 in (2008) |
| August 9 | 96.1°F (2018) | 37.9°F (2004) | 0.02 in (2016) |
| August 10 | 98.1°F (2018) | 37.0°F (2004) | 0.71 in (2013) |
| August 11 | 93.9°F (2025) | 42.1°F (2004) | 0.20 in (2013) |
| August 12 | 96.1°F (2021) | 46.0°F (2006) | 0.48 in (2013) |
| August 13 | 96.1°F (2004) | 43.0°F (2006) | 0.78 in (2014) |
| August 14 | 98.1°F (2004) | 43.0°F (2018) | 0.14 in (2009) |
| August 15 | 98.1°F (2023) | 44.1°F (2017) | 0.57 in (1950) |
| August 16 | 98.1°F (2023) | 39.9°F (2011) | 0.11 in (2025) |
| August 17 | 99.0°F (2008) | 42.1°F (2006) | 0.06 in (2005) |
| August 18 | 99.0°F (2008) | 44.1°F (2006) | 0.61 in (2024) |
| August 19 | 91.0°F (2012) | 42.1°F (2005) | 0.03 in (2008) |
| August 20 | 90.0°F (2009) | 44.1°F (2005) | 0.11 in (2008) |
| August 21 | 90.0°F (2006) | 41.0°F (1933) | 0.25 in (2008) |
| August 22 | 90.0°F (2006) | 39.0°F (1933) | 0.29 in (2004) |
| August 23 | 89.1°F (2025) | 39.0°F (1933) | 0.15 in (2024) |
| August 24 | 93.9°F (2025) | 39.9°F (2012) | 0.43 in (2004) |
| August 25 | 96.1°F (2025) | 37.9°F (2012) | 1.54 in (2004) |
| August 26 | 95.0°F (2025) | 34.0°F (1933) | 0.18 in (2008) |
| August 27 | 96.1°F (2025) | 39.0°F (1933) | 0.12 in (2008) |
| August 28 | 93.0°F (2023) | 39.0°F (2007) | 0.90 in (1951) |
| August 29 | 95.0°F (2023) | 39.0°F (2007) | 0.17 in (1951) |
| August 30 | 89.1°F (2003) | 37.9°F (2012) | 0.30 in (2005) |
| August 31 | 91.9°F (2022) | 39.0°F (2006) | 0.35 in (2014) |