When does the average daily temperature begin to rise?

MIKE MOSS SAYS:       John,     Using the daily climate normal from the National Climatic Data Center computed for the Raleigh-Durham airport, the normal (more or less a 30 year average ending with the most recent "zero" year) climbs from 49 to 50 degrees on January 19th following several days at 49, the coldest "normal high" of the year. That also represents the time that daily mean temperature begins to increase. Of course, these are based on long-term statistics, and any given year can have its coldest period anywhere from late December to late February or so.

Looking ahead some, the opposite reversal point in summer comes on July 23rd, when the normal high drops back to 89 degrees after a few days at 90.