0
Days with thunderstorms per month in Boulder
YearJANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDECYEAR
1971 0 0 0 4 7 16 13 6 4 3 0 0 53
1972 0 0 1 0 6 17 13 12 7 1 0 0 57
1973 0 0 0 2 6 8 16 15 6 0 0 0 53
1974 0 0 1 0 2 11 18 9 4 2 0 0 47
1975 1 0 0 0 4 10 14 11 4 1 0 0 45
1976 0 0 0 2 9 10 12 14 7 0 0 0 54
1977 0 0 0 6 10 11 19 12 3 0 0 0 61
1978 0 0 1 2 8 6 9 7 2 0 0 0 35
1979 0 0 0 0 5 6 16 12 4 0 0 0 43
1980 0 0 1 2 9 5 17 7 1 0 0 0 42
1981 0 0 0 0 12 11 13 17 9 0 0 0 62
1982 0 0 1 1 12 13 13 16 7 2 1 0 66
1983 0 1 2 0 5 16 18 13 5 1 1 0 62
199000136718151100061
1991001114171716600072
199200219121816210061
19930002148913600052
19940004991315721060
1995000213148111000058
1996000031511141110055
199700008191321410066
199800217101214710054
19990000991314400049
2000000333917410040
20010023571815810059
20020000510312610037
2003000101013116200052
200400126141712920063
20050002615119510049
200600007815124000 46
200700111148111562059
20080000 35 5 114 2 0 0 30
2009000 16 17 1510600055
20100002491010110037
2011000338207211149
20120004311164400
201300104101516720063
20140000
1990-2002 average0.00.00.51.37.810.511.814.86.8.70.080.054.4
1990-1996 std0.00.00.91.13.33.94.52.03.20.8.40.0X
1971-96 average0.10.10.51.68.211.114.312.65.80.70.20.0X
1971-96 std.2.20.71.63.53.83.33.22.80.9.40.0X

Thuderstorm data for 1971-present excludes the years 1984-1989 (not currently available). Data was taken by a different person for the time periods 1971-1983 and 1990-present. Days are 5pm MST to 5pm MST for 1990 to present and midnight-midnight for 1971-1983.