How often it actually gets hot in Tennessee — the number of days a year reaching 90 °F, 95 °F and 100 °F, how this year is running against that, and which counties take the worst of it. Counts are daily high temperatures from the NOAA nClimGrid gridded record, averaged across this area’s counties.
Daily maximum temperatures come from NOAA/NCEI’s nClimGrid-Daily gridded analysis, 1951–present, with the current year carried forward on the 2.5 km URMA analysis. A “90 °F day” is one whose high reached 90 anywhere in that county. Normals are the recent period. Area figures are the mean across the area’s counties — an area average, so a large county counts the same as a small one. The 1951-present series is published per state, not per county, so the trend chart is labelled with the state it describes.