Friday, July 15, 2016 3 P.M.
This has become an ongoing problem recently – wide model divergence on thunderstorm chances. It’s back again today. Both the GFS and NAM literally ignore the chances for thunderstorms later today while the short-term models develop storms in the area over the next few hours.
With a weak, slow-moving cold front lying over southern IN and plenty of low level moisture available, it should look like a no-brainer for storms. However, there are some problems. Even though the surface is moist, the upper air doesn’t appear to have much water to add. And, there’s no readily available upper air energy to initiate convection.
Still, the surface-based instability is high along the Ohio River. And we’re in the time of maximum daytime temperatures, so the surface conditions should suffice to create at least some small thunderstorms over the next few hours (until 7-8 P.M.) The cold front should also be favorable to allowing a nearly solid line of storms to form and drift southeast. So, it looks like most (if not all) of the Louisville Metro should experience a shower and/or thunderstorm later this afternoon