Terry’s Take: Late summer heat and September frost?

Posted on: 10:26 pm, September 3, 2013, by

Terry Swails Weather Blog

FROST AND SNOW BY THE END OF SEPTEMBER? A case can be made for just that based on late season heat waves like the one we just experienced. Meteorologist Jim Lee of the NWS in Des Moines did a nice analysis of the recent heat wave in Iowa. In it he pointed out a startling correlation between late season heat and a September cold snap. He made this quote regarding his findings,”following are some notes on a few of the more notable late summer heat waves on record in Iowa. It should be pointed out that in many (but not all) cases, extreme heat in late August and early September has been followed by early freezes and even snow later in September, as described below. This is certainly not an assurance that an early freeze will occur next month, but given the history of similar events, it is a possibility”.



Below I’ve included the link to the post and if nothing else it’s interesting reading about some of the wintry September weather that occurred following the late summer heat of 1983, 1976, 1939, 1913, 1895, and 1881. In all those years frost, and in some cases hard freezes (and snow) occurred by mid to late September. Now that’s a chilling thought!
Despite the evidence, I currently see no signs or trends that point towards such an occurrence. However, things can turn quickly once the winds of change decide to blow!