Technical: Strong to Severe Thunderstorms Likely Late This Afternoon
After some record warmth over the past few days, we are about to get our usual strong cold front “snap” back towards seasonable temperatures. But considering how warm and moist the atmosphere is initially, this means there will be quite an impressive temperature gradient, which is often a great fuel for storm development. Although the severe weather event in the Ohio Valley greatly underperformed (as expected), that does not necessarily portend an under-performer further east. While things do not necessarily lead to a major severe weather outbreak, the recent model guidance has actually trended a bit more impressive with a line of thunderstorms for late Saturday afternoon.
The reason this is happening is because there is a lot more backed low-level flow in our area compared to what the Ohio Valley had, meaning the surface winds are bending back to the southeast instead of the southwest. This adds more directional wind shear to the profile, considering winds just above the surface turn southwest — so that southeast to southwest turning with height provides some low-level rotation and thus a bit more organized updrafts. Additionally, there is a well-timed increase in the 850mb jet and lower just ahead of the strongest convection, allowing the line of thunderstorms to maintain its strength.