August weather in Grand Coulee, WA
The average temperature in Grand Coulee in August is 72.6°F (58.3°F–86.9°F). Average precipitation: 0.33 inches.
August is a summer month in Grand Coulee, and is warmer than the annual average of 49.9°F. Daily temperatures swing about 28.6°F between overnight low and afternoon high. Expect about 3 days with precipitation. Daylight averages about 14h 6m. For travel, August is a comfortable month to visit.
Avg High
86.9°F
Avg Low
58.3°F
Precipitation
0.33 in
Daylight
14h 6m
August records in Grand Coulee
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| August 1 | 104.0°F (1971) | 48.9°F (2006) | 0.05 in (1937) |
| August 2 | 102.9°F (1971) | 48.0°F (1964) | 0.27 in (2013) |
| August 3 | 106.0°F (1939) | 48.0°F (1976) | 0.40 in (1956) |
| August 4 | 109.9°F (1961) | 48.0°F (1956) | 1.22 in (1948) |
| August 5 | 104.0°F (1998) | 45.0°F (1948) | 0.56 in (2004) |
| August 6 | 99.0°F (1940) | 45.0°F (2002) | 0.30 in (2020) |
| August 7 | 100.0°F (1972) | 44.1°F (2002) | 0.42 in (1976) |
| August 8 | 105.1°F (1945) | 42.1°F (2010) | 0.25 in (2021) |
| August 9 | 105.1°F (1945) | 48.0°F (1944) | 0.06 in (2019) |
| August 10 | 102.9°F (1939) | 46.0°F (2002) | 0.36 in (2013) |
| August 11 | 104.0°F (1939) | 46.9°F (1949) | 0.72 in (2019) |
| August 12 | 102.9°F (1971) | 50.0°F (1957) | 0.38 in (2019) |
| August 13 | 102.9°F (2004) | 46.0°F (1985) | 0.21 in (1978) |
| August 14 | 104.0°F (2004) | 32.0°F (1985) | 0.57 in (1979) |
| August 15 | 102.9°F (2023) | 43.0°F (1972) | 0.76 in (2014) |
| August 16 | 102.9°F (1934) | 46.9°F (1995) | 0.67 in (1972) |
| August 17 | 102.9°F (1967) | 44.1°F (1976) | 0.16 in (1968) |
| August 18 | 104.0°F (2008) | 44.1°F (1995) | 0.45 in (1935) |
| August 19 | 102.9°F (1942) | 46.0°F (1945) | 0.25 in (1968) |
| August 20 | 102.0°F (1945) | 45.0°F (1945) | 0.28 in (1965) |
| August 21 | 102.0°F (1939) | 46.9°F (1945) | 0.77 in (1990) |
| August 22 | 100.9°F (1939) | 41.0°F (1960) | 0.41 in (2023) |
| August 23 | 100.9°F (1939) | 41.0°F (1992) | 0.38 in (2014) |
| August 24 | 102.9°F (1966) | 39.0°F (1975) | 0.75 in (1997) |
| August 25 | 100.0°F (1934) | 42.1°F (2003) | 0.48 in (1978) |
| August 26 | 104.0°F (1934) | 44.1°F (1976) | 1.15 in (1941) |
| August 27 | 100.0°F (1934) | 42.1°F (1960) | 0.64 in (1968) |
| August 28 | 102.0°F (1934) | 44.1°F (1966) | 1.02 in (1951) |
| August 29 | 100.9°F (1934) | 43.0°F (1965) | 0.18 in (1943) |
| August 30 | 98.1°F (1940) | 39.9°F (1951) | 0.78 in (2023) |
| August 31 | 102.9°F (1938) | 37.9°F (1951) | 0.33 in (1999) |