Coldest temperature:  36° May 4, 1940 and May 4, 1957
Coldest high temperature:  47° May 4, 1935 and May 4, 1957
Coldest average daily temperature:  42° May 4, 1957
(The cold temperatures on May 4, 1957 were accompanied by 20 to 25 mph north winds!)

Warmest temperature:  94° May 2, 1959
Warmest low temperature:  72° May 14, 1886
Warmest average daily temperature:  79° May 14, 1886

Wettest:  3.15" of rain May 5, 2018
Frozen precipitation:  On May 6, 1989 sleet was observed from 1:01pm to 1:05pm.
Out of the 150 Derby Days, 72 (48%) experienced rain at some point during the day.
Longest stretch of consecutive wet Derby Days (24-hr):  7 (2007-2013)
Longest stretch of consecutive wet Derby Days (1pm-7pm):  6 (1989-1994)
Longest stretch of consecutive dry Derby Days (24-hr):  8 (1937-1944)
Longest stretch of consecutive dry Derby Days (1pm-7pm):  12 (1875-1886)

(The above records, unless otherwise noted, are for the entire calendar day -- not necessarily race time. Also, the data were taken at the official observation site for the city of Louisville, not at Churchill Downs itself.)

For recent years, "Aftn/Early Eve Precipitation" = 2pm-8pm EDT.

Coldest temperature:  38° May 19, 1894
Coldest high temperature:  44° May 19, 1894
Coldest average daily temperature: 41°  May 19, 1894

Warmest temperature:  94° May 6, 1949
Warmest low temperature:  73° May 25, 1918
Warmest average daily temperature:  81.5°  May 25, 1918

Wettest:  1.40" May 5, 1961
Out of the 150 Kentucky Oaks Days, 79 (53%) experienced rain at some point during the day.
Longest stretch of consecutive wet Oaks Days (24-hr): 6 (1899-1904, 1943-1948, 1993-1998)
Longest stretch of consecutive wet Oaks Days (1pm-7pm):  3 (1945-47, 1989-91, 1996-98)
Longest stretch of consecutive dry Oaks Days (24-hr):  7 (1881-1887)
Longest stretch of consecutive dry Oaks Days (1pm-7pm):  10 (1969-1978)

(The above records, unless otherwise noted, are for the entire calendar day -- not necessarily race time. Also, the data were taken at the official observing site for the city of Louisville, not Churchill Downs itself.)

Coldest temperature: 34° in 2005
Coldest high temperature: 45° in 1999 
Coldest average daily temperature: 42.5° April 17, 1999 and April 23, 2005

Warmest temperature:  87° in 2022
Warmest low temperature: 64° in 2001 and 2002 
Warmest average daily temperature: 75° April 23, 2022

Wettest: 1.09" in 1996 
Frozen precipitation: Sleet was observed at Louisville International Airport in 1990. Sleet was observed at the venue in 2005.
Out of the 34 Thunder Over Louisville Days, 16 (47%) experienced rain at some point during the day
Longest stretch of consecutive wet Thunder Over Louisville Days (24-hr): 4 (1996-1999)
Longest stretch of consecutive wet Thunder Over Louisville Days (2pm-8pm): 2 (1998-1999)
Longest stretch of consecutive dry Thunder Over Louisville Days (24-hr):  4 (2013-2016)
Longest stretch of consecutive dry Thunder Over Louisville Days (2pm-8pm): 8 (1990-1997)

(The dates used below assume Thunder Over Louisville was held two Saturdays before the Kentucky Derby, with the exception of years in which that weekend was Easter weekend when Thunder was moved to the week before, and except for the 1990 Thunder since Thunder's web page indicates the event was held on April 17 that year.)

Data listed here were taken from the nearest official observing site for the city of Louisville, not at the venue site itself.

Banner photo credit: Aroun Kesavaraj. The image was cropped to fit the banner.