Longest stretch of 90° so far this year

Some of the hottest weather we've felt in years will be arriving in the Stateline later this weekend and persist into the middle to end of next week.  In anticipation of the upcoming heat, the Quad Cities NWS has issued an Excessive Heat Watch beginning Sunday afternoon and lasting through Wednesday evening for Stephenson, Jo Daviess, Carroll and Whiteside counties.  I do anticipate some type of watch or advisory to be extended further east in the upcoming days. 

Today's 87° is going to be the coolest we'll feel over the next week and a half as a very strong ridge of high pressure builds across the center of the country.  This will pull the hot air mass that has been bottled up in the south, thanks to a significant ongoing drought, northward.  Temperatures next week will rise into the low, middle and possibly upper 90s as the dew points rise into the lower 70s.  This will cause heat index values, starting Sunday, to top off near 100° and higher.  There may be a little break from the oppressive heat on Tuesday as a cold front tries to move through but because the ridge will be so strong, it likely won't make it through.  Wednesday could actually end up being the hottest day out of the week. 

So, how does this compare with the deadly heat wave that struck Chicago back in 1995?  Several factors contributed the significant amount of deaths that occurred that year.  The heat wave of 1995 started on July 12th and lasted through the 16th where temperatures ranged from 94°, on the 16th, all the way to 106° on the 13th.  Not only were the daytime temperatures very high, nighttime lows didn't fall past the mid 70s.  We often look for some type of relief at night and unfortunately didn't get that.  One of the factors that played into the lows not falling much was what is known as the "Urban Heat Island" effect.  You may have heard meteorologists talk of this and it's caused by a high concentration of buildings, parking lots and roads in urban areas.  These features tend to absorb more heat during the day and as a result, radiate more heat at night than the surrounding areas.  Lack of an ability to warn of the heat, power failures and residents who were reluctant to open windows, because of the fear of crime, also helped contribute to high number of deaths.  While I don't think we'll tip the century mark with temperatures, this is going to be the longest stretch of 90° we've felt in several years so it's best to be prepared now!