Most of the thunderstorms from earlier today are lifting north of our region. However, there are thunderstorms remaining in Delaware as of just before 5 PM. While the activity has been isolated, it has formed during the past two days over the portions of our region that are the most populated. Until dusk, I cannot rule out an additional isolated thunderstorm across our region as there is plenty of instability still in place and even the slightest trigger such as an outflow boundary could lift the air and pop a thunderstorm.
Later tonight, we should see a partly to mostly cloudy evening with very humid and uncomfortable conditions. The air at the surface may become quite stagnant just like last night. There will be some areas of fog developing, especially in areas that received measurable rainfall today. There is a slight chance of a thunderstorm in the western fringes of the region overnight, but I think most activity dies out after dusk and will not return until later Sunday.
On Sunday, another afternoon of scattered thunderstorms with some locally severe can be anticipated. Very high moisture content remains in place making it feel uncomfortable as it will be very humid. Later in the day, more organized clusters of thunderstorms or even a squall-line of some sort may approach the region. While we are under a slight risk of severe thunderstorms according to the Storm Prediction Center, the late day and nighttime arrival of the cold front and prefrontal thunderstorms leaves the coverage of severe weather with the front itself in doubt. Some gusty, southerly winds are possible Sunday Afternoon ahead of the cold front with gusts of 25 to 35 MPH possible. In Summary, as it stands right now…the greatest risk of severe weather will be west of the region tomorrow…with a chance of a few severe thunderstorms in our region.
Then here we go again with having to insert that chance of thunderstorms just about every single day in the extended forecast. On Monday, the cold front may stall in our southern areas. Does this stall in Southern NJ or Northern DE or move further south? It is hard to make that call at this moment with enough confidence. Points along and south of the front will have the best shot for thunderstorms while areas north of the front will likely see dropping humidity and mostly sunny conditions. Any thunderstorm ahead of the cold front on Monday could turn severe. The front puts on the breaks and begins to reverse as a warm front for the remainder of the week as waves of energy ride along it. Then a cold front will approach sometime on Friday, if not sometime on Saturday. At this time, Tuesday may be the driest day of the next seven.