As the city exemplifies the urban heat island effect, temperatures in commercial areas and in the industrialized areas along interstates are often higher than in the suburbs, often as much as 5 °F (2.8 °C).
 Louisville's lowest solar noon is 28.4 degrees with the shortest day-length being 9 hours and 30 seconds, both occurring from December 17–26. The city's highest solar noon is 75.2 degrees with the longest day-length being 14 hours and 39 seconds, both occurring from June 17–25. The city's March and September equinox occurs at 50.5 degrees.