Things have become hot and humid across the area the past couple of days. However, comparing the heat this year to that of last year (through July 18th) we see that there really is no comparison. Last year through this date there was a total of 47 days in Chicago (45 days at Rockford) in which the mercury topped out at 85 degrees or above. This year there have only been 22 such days in Chicago (19 days in Rockford), a far cry from last year. Even more impressive is difference in the number of 90+ degree days. In 2012 there was a total of 32 days through July 18th at both Chicago and Rockford with temperatures at or above 90. This year, those numbers have been 5 at Chicago and 10 at Rockford. The green bars have been corrected to represent the average number of 85+ and 90+ days through July 18th for a direct comparison. Therefore, although it has been unpleasant across the area the last few days, we can see that it was much worse last year.
The other interesting statistic is that of the annual precipitation (bottom figure above). This year Chicago has had a total of 29.07 inches of precipitation, which is the most precipitation through July 17th on record. This is also more than the 26.91 inches of precipitation that fell through the entire 2012 year. Similarly, very wet conditions have been in place this year in Rockford, albeit not record breaking. A total of 28.17 inches has fallen through July 17th, which is also already more than the 23.35 inches of precipitation that fell during the entire 2012 year. In stark contrast, last year up to this date we were ranking amongst some of the driest years on record at both Rockford and Chicago.
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