We have now seen three straight days with temperatures in the 80s after beginning last week in the lower 50s! The warm up has been courtesy of a dominant area of high pressure causing what meteorologists refer as the "Omega block" to develop. Once that set up in the Great Lakes, sunshine and southerly winds moved in, allowing temperatures to increase each day last week before hitting the 80s Saturday, Sunday and Monday. Those 80s were a good 20 degrees above normal for this time of year. And we won't be seeing temperatures that high for awhile.
So how abnormal is it to see 80s in mid-April? Well, it really isn't. In a normal year, we record our
first 80-degree day on April 20th. This year, that happened on April 16th, 17th and 18th. That is only four days off of the average first occurrence of 80°. We have hit 80° as early as March 15th, and we've gone as late as June 1st without seeing 80°. So, if you're wondering whether seeing the 80s is unusual for this time of year in Northern Illinois, the answer is not really. What is slightly abnormal is the fact that we saw three straight days in the lower 80s. Typically in mid-April, these types of warm ups are a one or maybe two day thing as colder air usually prevents them from lasting much longer. Hopefully you enjoyed the 80s because we may not be seeing them for quite some time!