The threat of severe weather has prompted the Storm Prediction Center to issue a slight risk for both Thursday and Friday which can be seen below.
Besides the infiltration of colder air behind the cold front, many factors will help lead to this severe threat. Taking a look at the latest 12Z NAM model run to view these, the first thing to notice is the upper air support that will be in place as the jet stream sinks into the United States from Canada. Below is what that may look like come Thursday evening and Friday evening.
As this trough digs and becomes more neutral, the storms will likely increase in intensity for Friday. While winds in the jet stream will only be about 50 knots above the Mid-Atlantic come Friday evening, this will still be more upper air support than this area has seen in awhile and therefore will help any thunderstorms that form that day.
The next thing to consider is the moist and unstable air mass that this front will be pushing into. Below are the images showing the dewpoint temperatures and CAPE values on Thursday evening and then below that on Friday evening.
What is being depicted here is a drastic change in the amount of moisture in the air before the front and behind the front. In front of this cold front, we may expect to see dewpoint temperatures on both Thursday and Friday in the 60s and perhaps lower 70s in a few places. CAPE values will likely remain between 1000 and 2000 J/kg for most but a few areas could see values reach at or above 3000 J/kg. Behind the front, CAPE values fall drastically to values closer to 0 as expected with a sharp cold front but more dramatically, dewpoint temperatures will fall to below 60 and in some cases to near 40! This drastic change will result in numerous thunderstorms initiating on both days as shown by the composite reflectivity from Thursday evening and Friday evening below.
Due to the fairly low shear environment across much of the threat area on most days, the threat of tornadoes should remain pretty low. However, a tornado or two cannot be ruled out, especially on Thursday across the Midwest. That being said, the main threat should be damaging winds with some large hail possible. Keep an eye on this developing situation as we head into the late work week.