AccuWeather.com meteorologists report the summer of 2012 is in the running for one of the top three hottest summers in the past 60 years in the United States and southern Canada.
Temperatures in and are expected to span the 100 to 102 degrees spectrum this week.
Steven Root, certified consulting meteorologist and president and CEO of WeatherBank, Inc. has been examining hourly and daily temperatures in 59 hub cities dating back to Jan. 1, 1950, according to materials provided Wednesday by Alex Sosnowski, AccuWeather.com expert senior meteorologist.
WeatherBank is an AccuWeather, Inc., long-range forecasting and data partner.
Root computes the cooling degree days (CDD) for each city, each day of the year. Cooling degree days are the number of degrees that a day's average temperature is above 65 degrees. The period from May 15 to Sept. 15 is considered to be the air conditioning/cooling season for the United States and Canada.
Root estimates this summer will finish up with 59,484 CDDs, based on what has happened so far and what is projected.
"The summer of 2012 is on pace to finish third hottest on the list of 62 summers since 1950, but is still in the running for number two or one on the list," Root told Sosnowski.
The hottest summer on Root's records was last year (2011) with 60,402 CDDs. The second hottest summer, according to Root, was 1951 with 60,078 CDDs. Comparatively, the coolest summer was 1965 with 43,337 CDDs.
Root's approximate 60-year average is 51,923 CDDs. The commonly used National Oceanic and Atmospheric Administration's (NOAA) most recent 30-year average is 53,933 CDDs. In the past 10 years, the average CDDs is 56,134.
"This tells you that the summers are trending hotter in the most recent decades and years for the U.S. and southern Canada as a whole," Root said.
According to AccuWeather.com's long-range forecasting department, headed by veteran meteorologist Paul Pastelok, "We expect more surges of heat to build out of the Plains and into the East in the coming weeks."