The high temperature this past Wednesday of 96 degrees was the warmest of the year. If that holds, it would continue our trend in recent years of our maximum yearly temperature being below the historical average. From 1900 through 1990 the average yearly maximum temperature was 99 degrees.
Since 1990 the average maximum has been 96 degrees. The abundant moisture since the early 1990s and the corresponding wetter soils tend to lower the potential air temperature. Plus, atmospheric patterns have rarely been conducive to high heat in the past two decades as well. That average maximum of just 96 in the past 20 years is even colder than the average maximum high in the 1880s. That decade, which is overall the coldest decade on record, had an average maximum yearly temperature of 98 degrees.
The only time frame which experienced cooler maximum temperatures then what has been recorded in recent years was in the first decade of the 1900s when the average yearly maximum was 94 degrees.