Back in my summer forecast, I predicted that the pattern for Summer 2007 would consist of ridges over the Southwest and Southeast and a primary storm track along the U.S.-Canadian border. As I mentioned in my mid-summer update, from a synoptic standpoint I wasn’t far off except for one small detail. I did not predict the pesky upper-level low that got trapped between the ridges that led to the flooding across the southern Plains during June and early July. Now that the upper level low has been swept away by the cold fronts of late July, the race to 100 is on!
As mentioned in the summer forecast, there has not been widespread 100 degree temperatures over Kentucky since the hot summer of 1999. That should change this week as a broad ridge will allow scorching air from the deserts to move across the southern plains into the Mid-South. It appears that eastern Missouri (St. Louis) and far western Kentucky (Paducah) will bear the worst of this hot blast as both are expected to have high temperatures around 100-103 Wednesday and Thursday with heat indices around 110. South-central KY (including Bowling Green) will likely hit 100 at least once this week (with the best chance Thursday or Friday) as the core of the hot air moves across the region.
How long will it last? Right now it is highly likely that the 95+ temperatures will continue through at least mid-month with very little chance of any meaningful precipitation. The GFS brings a cold front across the region after the 15th, but there is not much model support from the ensembles.
Bottom Line: While the summer of 2007 began with the promise of extreme heat, it looks like the reality of that extreme heat is finally here. This heat wave should push south-central KY into the extreme drought category by the end of August.