September U.S. Percentage Areas Very Warm/Very Cold
%
1895
25.45
12.02
1896
0.11
25.89
1897
26.19
5.82
1898
3.54
0.83
1899
2.48
4.21
1900
28.86
17.80
1901
0.00
23.34
1902
0.10
21.61
1903
0.00
20.09
1904
1.56
2.80
1905
5.40
0.00
1906
28.74
2.37
1907
0.96
9.10
1908
16.77
4.79
1909
0.00
6.12
1910
16.23
4.06
1911
36.41
11.98
1912
8.41
43.04
1913
0.35
19.48
1914
0.50
9.81
1915
3.33
6.04
1916
0.00
5.46
1917
0.00
13.25
1918
1.52
57.60
1919
1.33
1.51
1920
7.80
5.43
1921
45.67
12.19
1922
12.56
1.10
1923
0.00
9.84
1924
0.00
29.79
1925
35.27
12.54
1926
19.54
25.04
1927
6.88
11.40
1928
0.00
23.37
1929
0.00
17.49
1930
16.01
6.62
1931
61.83
1.81
1932
1.12
4.57
1933
61.44
5.06
1934
3.55
12.99
1935
2.43
9.46
1936
24.94
0.00
1937
1.57
2.73
1938
17.58
2.88
1939
32.92
0.00
1940
17.07
9.43
1941
9.42
28.81
1942
0.00
12.19
1943
7.70
13.27
1944
0.89
1.20
1945
9.88
0.25
1946
1.64
0.00
1947
15.45
0.00
1948
19.04
0.75
1949
2.04
21.89
1950
0.10
7.43
1951
2.04
17.96
1952
3.80
0.00
1953
4.94
0.00
1954
34.18
0.00
1955
0.90
0.00
1956
12.71
12.78
1957
1.46
1.38
1958
1.00
0.00
1959
6.58
0.00
1960
5.78
0.10
1961
11.36
39.30
1962
0.10
8.69
1963
26.83
9.39
1964
0.00
2.31
1965
0.00
48.59
1966
6.70
5.31
1967
14.97
31.69
1968
1.66
11.17
1969
2.17
0.19
1970
14.71
22.43
1971
8.21
18.61
1972
6.26
9.14
1973
1.34
3.88
1974
7.23
44.98
1975
0.90
41.92
1976
0.00
7.89
1977
12.49
0.00
1978
18.43
7.85
1979
22.84
3.04
1980
17.54
0.00
1981
0.50
2.39
1982
1.20
0.00
1983
12.23
3.24
1984
3.42
16.51
1985
0.00
36.06
1986
4.42
34.97
1987
2.93
0.48
1988
1.10
2.35
1989
0.90
12.81
1990
29.85
0.00
1991
6.75
9.42
1992
0.00
0.00
1993
0.00
24.72
1994
13.16
0.51
1995
6.46
2.56
1996
0.08
5.65
1997
11.88
0.00
1998
72.49
0.00
1999
3.53
0.00
2000
10.35
0.00
2001
25.23
2.57
2002
20.37
0.00
2003
14.80
3.22
2004
9.37
0.00
2005
47.34
0.00
2006
0.00
20.54
2007
12.10
0.00
2008
5.69
1.30
2009
30.79
0.00
2010
25.07
0.00
2011
30.98
0.69
2012
16.62
0.00
2013
25.45
0.00
2014
13.13
0.00
2015
58.26
0.00
2016
35.44
0.00
2017
14.46
0.00
2018
47.96
0.00
2019
60.68
0.00
2020
23.01
0.28
2021
43.88
0.00
2022
48.90
0.00
2023
42.85
0.00