Among those cities, first freeze — defined as the first calendar date from Aug. 1 onwards with low temperatures at or below 32°F — is happening 12 days later on average.
Zoom in: Cleveland's first freeze is arriving 16 days later on average in comparison to 1970.
Now, the first freeze typically occurs between Oct. 16-31.
Caveat: "First freeze" is different from "first frost," which can happen with slightly higher temperatures.