Temperature similarity

We all recognize the importance of weather on grass performance, grass species selection, and maintenance requirements. I've been studying ways to compare the growing conditions at different locations, and one approach that I've found interesting is shown in this chart.

I took the daily temperatures for PACE Turf member locations, and from those daily temperatures over the past five years I calculated average monthly high temperatures and average monthly low temperatures. That gave 24 monthly temperature values for each location:…