San Luis Obispo September 21 Weather Records

Daily averages and all-time records for weather in San Luis Obispo, California for the date of September 21.
September 21 All-Time Records
1893–2024
Highest temperature 107 °F 1943
Lowest temperature 45 °F 1970
Lowest daily high 62 °F 1945
Highest daily low 72 °F 1939
Most precipitation 0.04 inches 1990
September 21 Average Weather
1991–2020 1
Average high 80.0 °F
Average low 53.3 °F
Chance precipitation 4.7%
San Luis Obispo September 21 Weather by Year
Year High (°F) Low (°F) Precip. (inches) Snow (inches)
2023 73 55 0.00 n/a
2022 78 55 0.00 n/a
2021 83 56 0.00 n/a
2020 76 53 0.00 0.0
2019 91 57 0.00 0.0
2018 77 54 0.00 0.0
2017 72 53 0.00 0.0
2016 76 53 0.00 0.0
2015 99 64 0.00 0.0
2014 78 61 0.00 0.0
2013 70 58 0.01 0.0
2012 80 48 0.00 0.0
2011 76 57 0.00 n/a
2010 72 50 0.00 n/a
2009 82 56 0.00 n/a
2008 77 54 0.00 n/a
2007 76 47 0.00 n/a
2006 85 55 0.00 n/a
2005 80 50 0.00 n/a
2004 86 52 0.00 n/a
2003 90 48 0.00 n/a
2002 80 51 0.00 n/a
2001 74 55 0.00 n/a
2000 82 65 0.02 n/a
1999 73 46 0.00 n/a
1998 75 54 0.00 0.0
1997 85 53 n/a n/a
1996 82 50 0.00 0.0
1995 80 54 0.00 0.0
1994 78 53 0.00 0.0
1993 75 48 0.00 0.0
1992 83 50 0.00 0.0
1991 79 51 0.00 0.0
1990 80 51 0.04 0.0
1989 n/a 48 0.00 0.0
1988 68 55 n/a n/a
1987 92 50 0.00 0.0
1986 70 47 0.00 0.0
1985 72 49 0.00 0.0
1984 74 58 0.00 0.0
1983 94 60 0.01 0.0
1982 87 56 0.00 0.0
1981 85 51 0.00 0.0
1980 76 48 0.00 0.0
1979 90 53 0.00 0.0
1978 86 55 0.00 0.0
1977 77 54 0.00 0.0
1976 75 54 0.00 0.0
1975 77 50 0.00 0.0
1974 72 50 0.00 0.0
1973 75 55 0.00 0.0
1972 91 59 0.00 0.0
1971 72 53 0.00 0.0
1970 79 45 0.00 0.0
1969 70 52 0.00 0.0
1968 72 46 0.00 0.0
1967 94 58 0.00 0.0
1966 76 49 0.00 0.0
1965 79 51 0.00 0.0
1964 83 52 0.00 0.0
1963 74 53 0.00 0.0
1962 71 50 0.00 0.0
1961 67 54 0.00 0.0
1960 79 52 0.00 0.0
1959 74 52 0.00 0.0
1958 86 54 0.00 0.0
1957 75 50 0.00 0.0
1956 74 51 0.00 0.0
1955 75 55 0.00 0.0
1954 90 47 0.00 0.0
1953 72 54 0.00 0.0
1952 85 50 0.00 0.0
1951 83 53 0.00 0.0
1950 90 60 0.00 0.0
1949 81 51 0.00 0.0
1948 71 54 0.00 0.0
1947 95 57 0.00 0.0
1946 84 55 0.00 0.0
1945 62 59 0.00 0.0
1944 75 45 0.00 0.0
1943 107 50 0.00 0.0
1942 n/a 49 0.00 n/a
1941 78 52 0.00 n/a
1940 76 50 0.00 n/a
1939 102 72 0.00 n/a
1938 77 52 n/a n/a
1937 75 51 0.00 n/a
1936 75 51 0.00 n/a
1935 73 53 0.00 n/a
1934 69 55 0.02 n/a
1933 85 57 0.00 n/a
1932 72 50 0.00 n/a
1931 94 54 0.00 n/a
1930 76 58 0.00 n/a
1929 67 56 0.03 n/a
1928 70 48 0.00 n/a
1927 n/a n/a n/a n/a
1926 n/a n/a n/a n/a
1925 n/a n/a n/a n/a
1924 n/a n/a n/a n/a
1923 n/a n/a n/a n/a
1922 n/a n/a n/a n/a
1921 n/a n/a n/a n/a
1920 n/a n/a n/a n/a
1919 n/a n/a n/a n/a
1918 n/a n/a n/a n/a
1917 n/a n/a n/a n/a
1916 n/a n/a n/a n/a
1915 n/a n/a n/a n/a
1914 n/a n/a n/a n/a
1913 n/a n/a n/a n/a
1912 n/a n/a n/a n/a
1911 n/a n/a n/a n/a
1910 n/a n/a n/a n/a
1909 n/a n/a n/a n/a
1908 n/a n/a 0.00 n/a
1907 n/a n/a 0.00 0.0
1906 n/a n/a 0.00 0.0
1905 n/a n/a n/a n/a
1904 n/a n/a n/a n/a
1903 n/a n/a n/a n/a
1902 n/a n/a n/a n/a
1901 n/a n/a n/a n/a
1900 n/a n/a n/a n/a
1899 n/a n/a n/a n/a
1898 n/a n/a n/a n/a
1897 n/a n/a n/a n/a
1896 n/a n/a n/a n/a
1895 n/a n/a 0.00 n/a
1894 n/a n/a 0.00 n/a
1893 n/a n/a 0.00 n/a
What's the all-time high for San Luis Obispo on 9/21?
For the date of Sep 21, the highest temperature ever reached in San Luis Obispo history is 107 °F which happened in 1943.
Highest Temperatures in San Luis Obispo on September 21
Rank Temperature Year
1 107 °F 1943
2 102 °F 1939
3 99 °F 2015
4 95 °F 1947
5 94 °F 1931
5 94 °F 1967
5 94 °F 1983
8 92 °F 1987
9 91 °F 1972
9 91 °F 2019
What's the all-time low for San Luis Obispo on 9/21?
For the date of Sep 21, the lowest temperature ever reached in San Luis Obispo history is 45 °F which has happened 2 times, most recently in 1970.
Lowest Temperatures in San Luis Obispo on September 21
Rank Temperature Year
1 45 °F 1944
1 45 °F 1970
3 46 °F 1999
3 46 °F 1968
5 47 °F 2007
5 47 °F 1954
5 47 °F 1986
8 48 °F 1989
8 48 °F 1980
8 48 °F 2003
8 48 °F 1993
8 48 °F 2012
8 48 °F 1928
Lowest High Temperatures in San Luis Obispo on September 21
Rank Temperature Year
1 62 °F 1945
2 67 °F 1961
2 67 °F 1929
4 68 °F 1988
5 69 °F 1934
6 70 °F 1969
6 70 °F 1986
6 70 °F 2013
6 70 °F 1928
10 71 °F 1948
10 71 °F 1962
What's the most it has ever rained in San Luis Obispo on 9/21?
For the date of Sep 21, the most precipitation ever recorded in San Luis Obispo history is 0.04 inches which happened in 1990.
All-Time Most Precipitation in San Luis Obispo on September 21
Rank Precipitation Year
1 0.04 inches 1990
2 0.03 inches 1929
3 0.02 inches 2000
3 0.02 inches 1934
5 0.01 inches 2013
5 0.01 inches 1983
Weather Station Details
Years Station Coordinates
1999–2024 San Luis Obispo Airport location
1893–1998 San Luis Obispo Poly location
Notes
1: Daily averages are a moving average which includes 14 days before and after the date.
© H Brothers Inc, 2021–2024
Contact us | Privacy policy