August weather in Westby, MT
The average temperature in Westby in August is 65.9°F (51.8°F–80.0°F). Average precipitation: 1.64 inches.
August is a summer month in Westby, and is warmer than the annual average of 39.1°F. Daily temperatures swing about 28.2°F between overnight low and afternoon high. Daylight averages about 14h 11m. For travel, August is one of the best months of the year to visit.
Avg High
80.0°F
Avg Low
51.8°F
Precipitation
1.64 in
Daylight
14h 11m
August records in Westby
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| August 1 | 100.9°F (1989) | 39.0°F (2009) | 0.50 in (2001) |
| August 2 | 99.0°F (1983) | 35.1°F (1942) | 0.96 in (1998) |
| August 3 | 105.1°F (1947) | 36.0°F (1978) | 0.65 in (2000) |
| August 4 | 102.9°F (1961) | 43.0°F (1978) | 0.52 in (1951) |
| August 5 | 100.0°F (1983) | 41.0°F (1977) | 2.53 in (1965) |
| August 6 | 108.0°F (1983) | 43.0°F (1989) | 0.56 in (1950) |
| August 7 | 107.1°F (1983) | 44.1°F (1964) | 0.74 in (1944) |
| August 8 | 107.1°F (1958) | 36.0°F (2024) | 1.92 in (2025) |
| August 9 | 100.0°F (1940) | 37.0°F (2024) | 1.60 in (2006) |
| August 10 | 98.1°F (1978) | 37.9°F (1977) | 0.95 in (1980) |
| August 11 | 105.1°F (1984) | 36.0°F (1964) | 1.00 in (2007) |
| August 12 | 104.0°F (2018) | 34.0°F (1964) | 0.90 in (2010) |
| August 13 | 102.0°F (1984) | 39.0°F (1977) | 0.90 in (1947) |
| August 14 | 100.0°F (1961) | 35.1°F (1979) | 0.84 in (1974) |
| August 15 | 102.0°F (2015) | 36.0°F (1975) | 1.63 in (1968) |
| August 16 | 100.0°F (1958) | 36.0°F (1975) | 0.96 in (1980) |
| August 17 | 105.1°F (1958) | 34.0°F (1950) | 0.54 in (1947) |
| August 18 | 97.0°F (1945) | 39.0°F (1940) | 1.56 in (1968) |
| August 19 | 98.1°F (2023) | 36.0°F (1956) | 0.35 in (1948) |
| August 20 | 100.0°F (1942) | 30.9°F (2004) | 1.36 in (1966) |
| August 21 | 100.0°F (1969) | 36.0°F (2004) | 0.69 in (1966) |
| August 22 | 102.9°F (1971) | 37.9°F (1940) | 0.73 in (1990) |
| August 23 | 104.0°F (1976) | 35.1°F (1942) | 1.66 in (1968) |
| August 24 | 100.0°F (1952) | 28.9°F (1958) | 0.96 in (1965) |
| August 25 | 102.9°F (1952) | 33.1°F (1964) | 1.99 in (1960) |
| August 26 | 99.0°F (1939) | 37.0°F (1980) | 0.58 in (2002) |
| August 27 | 102.0°F (1971) | 34.0°F (1982) | 0.68 in (1942) |
| August 28 | 100.0°F (1971) | 37.0°F (1988) | 0.84 in (1997) |
| August 29 | 97.0°F (1972) | 37.0°F (1942) | 0.80 in (1975) |
| August 30 | 98.1°F (1948) | 34.0°F (1992) | 1.32 in (1951) |
| August 31 | 100.0°F (1983) | 35.1°F (1994) | 0.50 in (1952) |