Conditions are coming together for a widespread severe weather outbreak across the Great Lakes Region Wednesday evening into Wednesday night that could impact NW Ohio with widespread high wind. As of now here are the details of what I am expecting to develop but also remember that this will likely be adjusted a bit over the next 24 hours as new data comes in.
As of now, The National Weather Service has placed NW Ohio under a rare “Moderate Risk” for severe weather for Wednesday evening and Wednesday night.
A closer look at the region.
Notice that West Central Ohio is right on the edge of the higher risk area, that is because this anticipated Mesoscale Convective System, or, “MCS” will probably develop somewhere over Northern Illinois Wednesday evening and track SE toward Ohio into the overnight hours. An MCS is a large and organized area of thunderstorms that typically persists for several hours. They usually congeal or develop into a well-defined bow echo that can bring widespread wind damage to a region. Sometimes MCS’s can be classified as a Derecho, but that doesn’t happen until AFTER the storm has ended based on how widespread and long-lived the wind damage is. As of now, I don’t feel comfortable saying “possible Derecho” simply because we won’t know until after any damage is assessed.
Here is the set up for the system Wednesday evening. A strengthening area of low pressure will pull a warm front north up into Northern Illinois, Indiana, and NW Ohio late Wednesday evening. This will all develop in a very moist and unstable environment just to the south of the warm front. The area where the potential MCS will develop will likely lie right near the “Triple Point”, or in other words, in the region by the low, cold front, and warm front.
It’s important to note here that today’s weather forecast models typically have a VERY hard time forecasting exactly where an MCS will develop. So honestly, it won’t be until the system develops Wednesday evening that we’ll have a much better idea of where it will track. So for now I’m going to assume that it will track along the warm front which will extend into Western Ohio.
Very high wind shear values will be present along the warm front that will allow for this system to maintain most of its strength into the overnight hours as it tracks towards Western Ohio. If there is any silver lining to all of this it is that this system is expected to move through in the 10 PM to 3 AM timeframe, a time not typically best for severe weather. However, I do believe that the wind shear present in the atmosphere will be enough to overcome any loss of daytime heating and help maintain strength.
So here is the bottom line.
High wind will over 60 mph will be very possible with any thunderstorms from about 10 PM to 3 AM Wednesday night. Isolated tornadoes can also spin up along an MCS, but aren’t typically very strong. MCS systems also have the tendency to bring very heavy rain, flooding with this system is definitely a concern as well with over 2 inches of rain possible Wednesday night. Make a plan now to cover or secure anything outdoors Wednesday night and have a plan in place for your family in case warnings are issued. Here is my overall threat outlook.
I will definitely be watching this very closely and update as new data comes in!