September weather in Rockville, MD
The average temperature in Rockville in September is 68.7°F (60.0°F–77.5°F). Average precipitation: 4.01 inches.
September is a fall month in Rockville, and is warmer than the annual average of 56.2°F. Daily temperatures swing about 17.5°F between overnight low and afternoon high. Expect about 10 days with precipitation. Daylight averages about 12h 14m. For travel, September is a comfortable month to visit.
Avg High
77.5°F
Avg Low
60.0°F
Precipitation
4.01 in
Daylight
12h 14m
September records in Rockville
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 96.1°F (1953) | 48.0°F (1976) | 4.00 in (1952) |
| September 2 | 96.1°F (1953) | 42.1°F (1970) | 1.98 in (1959) |
| September 3 | 95.0°F (1953) | 43.0°F (1920) | 1.40 in (1982) |
| September 4 | 95.0°F (1953) | 44.1°F (1916) | 1.38 in (1999) |
| September 5 | 98.1°F (1954) | 46.0°F (1914) | 2.99 in (1979) |
| September 6 | 99.0°F (1954) | 45.0°F (1982) | 3.67 in (1979) |
| September 7 | 98.1°F (1954) | 42.1°F (1976) | 0.95 in (1974) |
| September 8 | 97.0°F (1919) | 46.0°F (1962) | 4.07 in (1987) |
| September 9 | 97.0°F (1919) | 39.9°F (1979) | 1.55 in (1974) |
| September 10 | 93.9°F (1964) | 36.0°F (1914) | 1.29 in (1909) |
| September 11 | 93.9°F (1964) | 32.0°F (1917) | 3.16 in (1996) |
| September 12 | 93.0°F (1964) | 35.1°F (1917) | 2.62 in (1960) |
| September 13 | 93.0°F (1915) | 37.0°F (1917) | 1.11 in (1949) |
| September 14 | 91.0°F (1915) | 35.1°F (1975) | 2.36 in (1973) |
| September 15 | 91.9°F (1915) | 39.9°F (1975) | 0.95 in (1916) |
| September 16 | 93.0°F (1991) | 37.0°F (1979) | 2.36 in (1976) |
| September 17 | 93.9°F (1991) | 35.1°F (1979) | 1.96 in (1957) |
| September 18 | 90.0°F (1958) | 39.0°F (1979) | 1.55 in (1918) |
| September 19 | 91.9°F (1965) | 39.9°F (1916) | 1.05 in (2000) |
| September 20 | 91.0°F (1965) | 32.0°F (1979) | 0.90 in (1964) |
| September 21 | 91.0°F (1965) | 37.0°F (1916) | 1.07 in (1979) |
| September 22 | 95.0°F (1980) | 37.9°F (1962) | 2.40 in (1979) |
| September 23 | 93.9°F (1970) | 36.0°F (1918) | 1.92 in (1975) |
| September 24 | 93.0°F (1959) | 28.0°F (1974) | 2.17 in (1912) |
| September 25 | 93.0°F (1970) | 34.0°F (1974) | 2.00 in (2000) |
| September 26 | 91.9°F (1958) | 37.9°F (1967) | 4.46 in (1975) |
| September 27 | 93.0°F (1998) | 35.1°F (1914) | 2.51 in (1985) |
| September 28 | 90.0°F (1954) | 34.0°F (1914) | 1.60 in (1974) |
| September 29 | 91.0°F (1954) | 30.0°F (1978) | 1.97 in (1963) |
| September 30 | 90.0°F (1986) | 35.1°F (1978) | 1.40 in (1920) |