"Figure 1. Number of Unfrozen Days in the Contiguous 48 States, 1979–2023",
Source: EPA's Climate Change Indicators in the United States: www.epa.gov/climate-indicators,
"Data source: Kim and Kimball, 2024",
Web update: January 2025,
Units: days,
,
Year,Deviation from long-term average
1979,-5.422511111
1980,-13.25851111
1981,-5.925511111
1982,-9.669511111
1983,-9.401511111
1984,-7.404511111
1985,-12.12951111
1986,0.809488889
1987,-1.909511111
1988,-1.872511111
1989,-7.889511111
1990,-4.155511111
1991,-2.058511111
1992,5.745488889
1993,1.917488889
1994,-7.115511111
1995,1.115488889
1996,-11.93551111
1997,-1.152511111
1998,4.221488889
1999,2.903488889
2000,-5.046511111
2001,7.700488889
2002,-9.664511111
2003,-5.566511111
2004,3.590488889
2005,1.458488889
2006,2.653488889
2007,1.015488889
2008,2.000488889
2009,1.411488889
2010,7.102488889
2011,4.548488889
2012,12.61748889
2013,-7.446511111
2014,-0.969511111
2015,11.36548889
2016,16.38348889
2017,13.03448889
2018,-4.032511111
2019,0.992488889
2020,8.760488889
2021,10.27848889
2022,-4.920511111
2023,17.32048889