This is a tell-all expose - a rigorous attempt to plumb the depths of meteorological science to lay bare the inscrutable secrets behind the annual progression of daily air temperatures across the greater Atlanta metropolitan area. A major heat island.
The graph above plots 8500 daily air temperatures recorded by the National Weather Service at the Atlanta Airport from 1980 thru 2003. These are daily average temperatures, mind you, averaged over a full 24-hour day, not the detested afternoon maximums experienced by thousands during their commutations over hot asphalt.
Applying non-linear least squares, the following harmonic regression model was fitted to these data to isolate the fundamental forcing functions:
Predicted daily temperature = M + A*(sin(2*Pi*T)/365 + C)
M = long-term average temperature was found to be 62.95 deg F;
A = the maximum degrees above this average equals 18.51 F; and,
C = the seasonal phase shift becomes 4.48.
Apparently, in Atlanta the prevailing summer temperatures are much higher than those in winter reaching a maximum in July. However, during any particular year daily maximums can occur just about any time, with winter temperatures up-and-down all over the place.
Title: © Atlanta Air Temperatures.
Series: None of the Above
Location: Atlanta, Georgia
Date: February 2005