September weather in Sullivan's Island, SC
The average temperature in Sullivan's Island in September is 76.8°F (67.7°F–85.9°F). Average precipitation: 5.47 inches.
September is a fall month in Sullivan's Island, and is warmer than the annual average of 65.5°F. Daily temperatures swing about 18.2°F between overnight low and afternoon high. Daylight averages about 12h 11m. For travel, September is a wet month.
Avg High
85.9°F
Avg Low
67.7°F
Precipitation
5.47 in
Daylight
12h 11m
September records in Sullivan's Island
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 96.1°F (1958) | 62.1°F (1999) | 2.90 in (1988) |
| September 2 | 96.1°F (1991) | 57.0°F (1968) | 1.99 in (1983) |
| September 3 | 96.1°F (2012) | 55.0°F (2007) | 1.07 in (1958) |
| September 4 | 97.0°F (1961) | 63.0°F (1979) | 4.50 in (1979) |
| September 5 | 97.0°F (2020) | 57.0°F (2007) | 2.75 in (1977) |
| September 6 | 95.0°F (1983) | 60.1°F (1997) | 1.59 in (1993) |
| September 7 | 97.0°F (1970) | 60.1°F (1988) | 2.35 in (2004) |
| September 8 | 97.0°F (2012) | 60.1°F (1988) | 2.60 in (2014) |
| September 9 | 96.1°F (2010) | 57.0°F (1956) | 1.91 in (1988) |
| September 10 | 99.0°F (2010) | 54.0°F (1972) | 1.69 in (2021) |
| September 11 | 93.9°F (1985) | 55.9°F (1956) | 3.95 in (1975) |
| September 12 | 93.9°F (1991) | 61.0°F (1967) | 3.08 in (1958) |
| September 13 | 90.0°F (1953) | 57.9°F (1967) | 3.06 in (1955) |
| September 14 | 93.9°F (1972) | 54.0°F (1985) | 1.91 in (2016) |
| September 15 | 93.9°F (1970) | 57.9°F (1969) | 3.49 in (2016) |
| September 16 | 96.1°F (2008) | 59.0°F (1961) | 0.90 in (2011) |
| September 17 | 93.9°F (1972) | 57.0°F (1961) | 2.01 in (2023) |
| September 18 | 95.0°F (1958) | 57.9°F (1969) | 2.00 in (1988) |
| September 19 | 91.9°F (2019) | 52.0°F (1981) | 2.55 in (2023) |
| September 20 | 91.0°F (2016) | 50.0°F (2008) | 1.37 in (1979) |
| September 21 | 96.1°F (2010) | 48.0°F (2008) | 1.76 in (1952) |
| September 22 | 95.0°F (1988) | 46.0°F (2008) | 2.22 in (1952) |
| September 23 | 93.9°F (2018) | 54.0°F (1983) | 0.74 in (1951) |
| September 24 | 95.0°F (2018) | 54.0°F (1963) | 0.65 in (2009) |
| September 25 | 93.9°F (2018) | 55.9°F (1981) | 3.05 in (1975) |
| September 26 | 93.9°F (2018) | 51.1°F (2008) | 4.70 in (2002) |
| September 27 | 91.0°F (2019) | 53.1°F (1984) | 2.90 in (1953) |
| September 28 | 93.9°F (2018) | 51.1°F (1993) | 3.08 in (1997) |
| September 29 | 91.9°F (2017) | 48.0°F (1970) | 4.20 in (2014) |
| September 30 | 91.0°F (2018) | 48.9°F (1967) | 1.95 in (2010) |