Derecho May Strike Ohio Valley Tomorrow

For the 9:55 PM CDT Update (7/23), CLICK HERE

There does appear to be potential for yet another derecho tomorrow into the Ohio Valley and Mid Atlantic regions, as the latest NAM model shows a strong bowing segment of storm cells storming through the Ohio Valley at around 4:00 PM CDT. With the potential for a second derecho, one begins to wonder, how does this happen? This summer, there has been a strong ridge of high pressure stationed over much of the Plains into other portions of the nation, and around this ridge is called the 'Ring of Fire' This Ring of Fire earns its name by being the hotspot for multiple complexes of showers and thunderstorms on an almost daily basis. This happens by a warm, moist and unstable air mass surging into an area. The Ring of Fire, which carries with it the Lower Level Jet stream, combines instability and wind shearing into the potential for potentially multiple complexes of showers and storms, also called a mesoscale convective system (MCS). This potential derecho situation looks to be part of this Ring of Fire. 

According to the latest 12z WRF run shown on the left, valid for tomorrow afternoon, there is also a derecho shown, but this one goes more into the Mid Atlanti than into the Ohio Valley. Either way, the potential remains for significant storms to fire tomorrow in the Ohio Valley and Mid Atlantic, and this could become a derecho. It will certainly have to be monitored.

Andrew