Late season heat wave could be the longest in over two decades for St. Joseph

A late season scorcher has settled into much of the United States this week, stretching from the deep south to parts of the Midwest. For Northwest Missouri and Northeast Kansas daily record high temperatures have yet to be broken this time around, although the longevity of daily high temperatures at or above 95 degrees has been significant.

As of Friday, Sep. 4, St. Joseph has had 7 consecutive days of 95 + degree heat. This number will likely continue rising, as a stagnant pattern remains anchored in place through the weekend and early next week. If the streak continues through Saturday, that would mark 8 days, the longest stretch of 95+ degree temperatures in St. Joseph since a 13-day scorcher in August of 2003. 

St. Joseph’s longest 95+ degree stretch ever recorded was 19 days. Believe it or not this took place on two separate occasions, first in July of 1934, then again in August of 1936. These brutal heat waves occurred in tandem with crippling drought during the infamous Dust Bowl, a period when St. Joseph’s all-time record high temperature of 110 degrees was also achieved in 1934.

Speaking of crops, the drying process of mature corn has begun taking place in recent weeks. As cornstalks release less moisture through transpiration, also known as corn sweat, oppressive humidity becomes less of an issue this time of year. While relatively moist air can still migrate northward from the Gulf in September, the absence of corn sweat means heat index values are less likely to soar above 110 degrees like they did in July and early August. On the flip side, less humid air masses are able to heat up more efficiently, allowing actual temperatures to spike by several more degrees.