I have to report an error in zone America/Kentucky/Louisville zdump gives zdump -V -c 1945,1950 America/Kentucky/Louisville America/Kentucky/Louisville Tue Aug 14 22:59:59 1945 UT = Tue Aug 14 17:59:59 1945 CWT isdst=1 gmtoff=-18000 America/Kentucky/Louisville Tue Aug 14 23:00:00 1945 UT = Tue Aug 14 18:00:00 1945 CPT isdst=1 gmtoff=-18000 America/Kentucky/Louisville Sun Sep 30 06:59:59 1945 UT = Sun Sep 30 01:59:59 1945 CPT isdst=1 gmtoff=-18000 America/Kentucky/Louisville Sun Sep 30 07:00:00 1945 UT = Sun Sep 30 01:00:00 1945 CST isdst=0 gmtoff=-21600 America/Kentucky/Louisville Tue Jan 1 05:59:59 1946 UT = Mon Dec 31 23:59:59 1945 CST isdst=0 gmtoff=-21600 America/Kentucky/Louisville Tue Jan 1 06:00:00 1946 UT = Tue Jan 1 01:00:00 1946 CDT isdst=1 gmtoff=-18000 America/Kentucky/Louisville Sun Jun 2 06:59:59 1946 UT = Sun Jun 2 01:59:59 1946 CDT isdst=1 gmtoff=-18000 America/Kentucky/Louisville Sun Jun 2 07:00:00 1946 UT = Sun Jun 2 01:00:00 1946 CST isdst=0 gmtoff=-21600 America/Kentucky/Louisville Sun Apr 27 07:59:59 1947 UT = Sun Apr 27 01:59:59 1947 CST isdst=0 gmtoff=-21600 America/Kentucky/Louisville Sun Apr 27 08:00:00 1947 UT = Sun Apr 27 03:00:00 1947 CDT isdst=1 gmtoff=-18000 with a strange transition CST to CDT on 1 January 1946. I have searched Louisville newspaper archives and find no report of such a clock change around New Year 1946. I find however the begin of CDT for 28 April 1946, and the switch back to CST on 2 June 1946. Shanks also has the transition on 28 April 1946. The cause I thnk is the strange formulation of Louisville rules # This also includes Clark, Floyd, and Harrison counties in Indiana. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER Rule Louisville 1921 only - May 1 2:00 1:00 D Rule Louisville 1921 only - Sep 1 2:00 0 S Rule Louisville 1941 1961 - Apr lastSun 2:00 1:00 D Rule Louisville 1941 only - Sep lastSun 2:00 0 S Rule Louisville 1946 only - Jun 2 2:00 0 S Rule Louisville 1950 1955 - Sep lastSun 2:00 0 S Rule Louisville 1956 1960 - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Kentucky/Louisville -5:43:02 - LMT 1883 Nov 18 12:16:58 -6:00 US C%sT 1921 -6:00 Louisville C%sT 1942 -6:00 US C%sT 1946 -6:00 Louisville C%sT 1961 Jul 23 2:00 -5:00 - EST 1968 -5:00 US E%sT 1974 Jan 6 2:00 -6:00 1:00 CDT 1974 Oct 27 2:00 -5:00 US E%sT I attach a newspaper article describing the swith on 28 April.
