How many 90° days has Charlotte had this season and what is their all-time record for that mark?
Posted October 13, 2007
MIKE MOSS SAYS: Pete, So far this year Charlotte has logged 75 days reaching or exceeding 90 degrees. The record for that city is 88 days in 1954.
Note that you had another question regarding record soil temperatures and whether this year produced record values that might delay the occurrence of the year's first frost. I do not currently have access to a soil temperature climatology that would provide normals and records to compare this year's readings to, but on physical principles it is likely that the extreme air temperatures that we experienced, especially in August, would lead to extreme soil temperatures as well. Since the heat capacity and somewhat slow conduction of heat through soil results in a storage factor and a lag in the uptake or release oh heat from soil, it seems plausible that especially warm soil temperatures could result in a small delay in the first occurence of frost for the year, at least in terms of frost on the ground (as opposed to rooftops, mailboxes, vehicle roofs and the like). This is difficult to quantify, but would likely be a relatively small effect.