September weather in Lebanon, NH
The average temperature in Lebanon in September is 60.7°F (48.6°F–72.9°F). Average precipitation: 3.44 inches.
September is a fall month in Lebanon, and is warmer than the annual average of 46°F. Daily temperatures swing about 24.3°F between overnight low and afternoon high. Expect about 13 days with precipitation. Daylight averages about 12h 17m. For travel, September is a comfortable month to visit.
Avg High
72.9°F
Avg Low
48.6°F
Precipitation
3.44 in
Daylight
12h 17m
September records in Lebanon
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 95.0°F (2010) | 37.9°F (1970) | 1.73 in (1965) |
| September 2 | 93.9°F (2010) | 36.0°F (2017) | 1.40 in (2019) |
| September 3 | 91.9°F (1999) | 37.9°F (1970) | 1.35 in (1974) |
| September 4 | 91.0°F (1999) | 39.0°F (1963) | 1.64 in (1966) |
| September 5 | 91.0°F (2018) | 34.0°F (2000) | 0.74 in (2011) |
| September 6 | 93.0°F (2023) | 35.1°F (1962) | 2.06 in (1985) |
| September 7 | 91.9°F (2023) | 33.1°F (1962) | 0.79 in (2011) |
| September 8 | 91.9°F (2002) | 39.0°F (1962) | 1.20 in (1987) |
| September 9 | 95.0°F (2002) | 36.0°F (2013) | 1.90 in (1987) |
| September 10 | 93.0°F (2002) | 34.0°F (1978) | 1.30 in (2015) |
| September 11 | 93.0°F (2013) | 34.0°F (1963) | 2.93 in (1968) |
| September 12 | 88.0°F (1982) | 36.0°F (1965) | 0.98 in (1971) |
| September 13 | 87.1°F (1982) | 32.0°F (1963) | 1.70 in (2015) |
| September 14 | 87.1°F (2005) | 28.0°F (1963) | 1.07 in (1977) |
| September 15 | 84.9°F (2024) | 30.9°F (1963) | 1.12 in (1998) |
| September 16 | 88.0°F (2018) | 30.0°F (1964) | 4.70 in (1999) |
| September 17 | 86.0°F (2018) | 34.0°F (2013) | 0.82 in (1999) |
| September 18 | 86.0°F (2018) | 34.0°F (2020) | 1.31 in (1970) |
| September 19 | 87.1°F (2024) | 29.1°F (2020) | 1.64 in (2022) |
| September 20 | 90.0°F (1983) | 28.0°F (1979) | 1.36 in (2001) |
| September 21 | 89.1°F (1965) | 27.0°F (1962) | 1.30 in (1974) |
| September 22 | 90.0°F (1965) | 28.2°F (2020) | 1.82 in (1981) |
| September 23 | 86.0°F (2017) | 27.0°F (1963) | 1.42 in (2003) |
| September 24 | 91.9°F (2017) | 19.9°F (1963) | 1.02 in (1965) |
| September 25 | 90.0°F (2017) | 24.1°F (1963) | 1.77 in (2025) |
| September 26 | 89.1°F (2017) | 30.0°F (1966) | 1.04 in (2024) |
| September 27 | 89.1°F (2017) | 26.1°F (1965) | 1.99 in (1985) |
| September 28 | 86.0°F (2025) | 24.1°F (1965) | 0.75 in (1981) |
| September 29 | 82.9°F (2025) | 25.0°F (2000) | 1.21 in (1963) |
| September 30 | 82.0°F (1986) | 28.0°F (1981) | 2.29 in (2015) |