Yesterday I hypothesized that using ranked air temperatures would provide people with the ability to judge August air temperatures against long-term averages. One of the strengths of the method I proposed was the ability to look at how common an observed temperature was. In the graph below, I organized data collected from NOAA into three ranked air temperature lines (Minimum, Mean, and Maximum observed temperatures) for Ann Arbor from 1926-2006.
Using this graph, it is now possible to see how far removed from the median observed mean air temperature for the month of August was in the fair city of Ann Arbor. Looking at the reported average temperature (from weatherunderground.com) for August 2007, we can see that an average daily temperature of 71F means that (on average) August air temperatures were around the 25th percentile. Similarly, average daily high temperatures for August 2007 was 80F; ~37th percentile. The average daily low temperature for the same period was 55F; ~20th percentile. All three numbers point to an August that was - for Ann Arbor - cooler than the 80 year median for all three parameters.