Heat Index Counts for the Jacksonville International Airport (JAX)
Counts represent the total number of days each year when the maximum heat index reached or exceeded the threshold temperature (1973 - current).
| Year | ≥ 100°F | ≥ 105°F | ≥ 108°F | ≥ 110°F | ≥ 115°F |
|---|---|---|---|---|---|
| 1973 | 25 | 2 | 0 | 0 | 0 |
| 1974 | 6 | 0 | 0 | 0 | 0 |
| 1975 | 26 | 0 | 0 | 0 | 0 |
| 1976 | 30 | 5 | 0 | 0 | 0 |
| 1977 | 62 | 8 | 2 | 1 | 0 |
| 1978 | 45 | 11 | 5 | 3 | 0 |
| 1979 | 44 | 11 | 3 | 0 | 0 |
| 1980 | 83 | 28 | 16 | 12 | 5 |
| 1981 | 69 | 41 | 19 | 12 | 2 |
| 1982 | 58 | 15 | 6 | 1 | 0 |
| 1983 | 45 | 11 | 5 | 3 | 0 |
| 1984 | 18 | 1 | 1 | 1 | 0 |
| 1985 | 30 | 5 | 4 | 2 | 1 |
| 1986 | 49 | 8 | 5 | 3 | 0 |
| 1987 | 57 | 15 | 4 | 3 | 0 |
| 1988 | 38 | 9 | 0 | 0 | 0 |
| 1989 | 40 | 5 | 2 | 0 | 0 |
| 1990 | 46 | 11 | 2 | 0 | 0 |
| 1991 | 66 | 8 | 3 | 1 | 0 |
| 1992 | 43 | 6 | 1 | 0 | 0 |
| 1993 | 65 | 20 | 11 | 5 | 0 |
| 1994 | 34 | 3 | 0 | 0 | 0 |
| 1995 | 44 | 15 | 7 | 2 | 0 |
| 1996 | 23 | 4 | 2 | 1 | 0 |
| 1997 | 33 | 3 | 2 | 2 | 0 |
| 1998 | 70 | 26 | 13 | 3 | 1 |
| 1999 | 35 | 15 | 8 | 5 | 2 |
| 2000 | 35 | 5 | 3 | 1 | 0 |
| 2001 | 19 | 1 | 0 | 0 | 0 |
| 2002 | 20 | 4 | 1 | 0 | 0 |
| 2003 | 12 | 0 | 0 | 0 | 0 |
| 2004 | 36 | 5 | 1 | 0 | 0 |
| 2005 | 49 | 10 | 2 | 1 | 0 |
| 2006 | 23 | 1 | 0 | 0 | 0 |
| 2007 | 34 | 8 | 4 | 1 | 0 |
| 2008 | 8 | 0 | 0 | 0 | 0 |
| 2009 | 33 | 5 | 2 | 0 | 0 |
| 2010 | 67 | 21 | 4 | 2 | 1 |
| 2011 | 46 | 7 | 2 | 1 | 0 |
| 2012 | 28 | 4 | 2 | 0 | 0 |
| 2013 | 25 | 0 | 0 | 0 | 0 |
| 2014 | 24 | 4 | 0 | 0 | 0 |
| 2015 | 46 | 10 | 3 | 0 | 0 |
| 2016 | 59 | 11 | 3 | 0 | 0 |
| 2017 | 51 | 8 | 2 | 1 | 1 |
| 2018 | 56 | 4 | 0 | 0 | 0 |
| 2019 | 48 | 11 | 5 | 2 | 0 |
| 2020 | 55 | 10 | 2 | 0 | 0 |
| 2021 | 25 | 4 | 1 | 0 | 0 |
| 2022 | 53 | 13 | 2 | 0 | 0 |
| 2023 | 60 | 22 | 12 | 6 | 1 |
| 2024 | 62 | 26 | 3 | 0 | 0 |
| 2025 | 61 | 26 | 15 | 6 | 1 |
| Average | 42 | 10 | 4 | 2 | 0 |
