Since the 1960s, temperatures across the Southeast and the entire world have been increasing, although there is a lot of year-to-year variability which is the bane of farmers everywhere. For the Southeast, a temperature increase of 1 degree F translates into a roughly one-week increase in the length of the growing season based on some work I did with Melissa Griffin (FSU climatologist at that time, and now with the South Carolina SC Office). However, frosts are related more to short-term weather patterns rather than climate trends, so late frosts will continue to be a serious problem even when spring blooms are coming earlier than in the past due to warmer temperatures. Insurance Journal ran an article this week discussing some of the changes that are being seen and how it will impact plant behavior in the future. You can read it here.
If you are interested in seeing the trends of temperature and precipitation for your area, check out the “Climate at a Glance” tool from NCEI at https://www.ncdc.noaa.gov/cag/regional/time-series/. You can adjust this to look at different regions or subregions and also to look at different weather variables. If you do that you will see that most of the warming is from increases in nighttime (minimum) temperature, with only small increases in daytime (maximum) temperatures. Here are some examples for the April through September main growing season.
