No repeat of last year’s late June string of eight 90s

Last summer’s most enduring hot spell began one year ago and included eight consecutive days with temperatures 90° or higher. The coming week will be very different, with little prospect of another 90° reading. It’s likely only four 90s will be on Chicago’s 2006 books as June closes. Past years with similar 90° counts heading into July have often gone on to produce cooler than average meteorological summers—below the long term average by 0.9°. Such years have also tended to finish with fewer 90s—19 versus the long term average of 24. There is no guarantee this season’s weather will respond in precisely the same way, but past trends can offer insights into what’s ahead.
T-storms Thursday produced some wild weather, including morning hail and downpours —ultimately slashing dewpoints (which reflect atmospheric moisture) from Wednesday’s four year high of 77° to 57° by nightfall Thursday.
-Tom Skilling