Before we talk about the Fall weather that arrives by the end of the week, we have the feature in the atmosphere that will bring us storms Tuesday night. A developing Low pressure will send a cold front across the Four states that will then produce a squall line. Squall lines are known for the strong wind and also the initial heavy rainfall and both of these factors will occur Tuesday evening and Wednesday Morning.
The Storm Prediction Center has placed a Slight Risk over the entire 4 states area. The overly humid air and sunshine that is forecasted for Tuesday morning will give the air enough energy for any storm to become a thunderstorm or even a severe storm. There is one factor that has become somewhat of a toss up and that is the wind shear.
Shear is what keeps storms alive but is also the source of tornadic weather. The wind shear profile favors a strong wind setup but not enough spin to lean me towards a worry for tornadic storms.
The Weather Prediction Center has between 1 and 2 inches of total rainfall for the system Tuesday night and Wednesday morning. We have had humid air for quite a while now. The dewpoint has sat between 65 and 70 for two weeks now and now we have a cold front to provide lift. That lifting will form and fuel our storms that will result in rainfall through the night and into Wednesday morning. The dewpoint has another quality that doesn’t fully represent humidity though.
This morning our dewpoint is in the upper 60s which is excessively high for the second week of October. When the dewpoint reaches this level, it releases “energy” into the air called latent heat. Latent heat is basically gasoline for the engines of the storms that are produced. Add in direct sun light and you can get a strong to severe setup for storms. For us, direct sunlight might be hard to come by. Therefore, keeping our risk for severe weather lower.
The cold front that is the driver for our severe weather, will also be the driver for the Fall weather! Yes, sweater weather kicks off Thursday and I couldn’t be happier. I’m aware that a good majority of us are not the biggest fans of colder air but let us Winter folk get excited! The cold air arriving means the allergens will die off, the insect population will drop, and the air will become a bit more comfortable for all of us.