Concerns For The Fourth……
With most on vacation this week and all of the 4th of July parties and bar-b-q’s nobody wants to see a thunderstorms roam through their backyard. Thankfully, today’s storms were isolated and relatively weak…all have dissipated and with high pressure settling in for the next 24 hours don’t expect to see any tonight or tomorrow.
The 4th on the other is looking pretty active when it comes to thunderstorms. First of all, insane heat in the middle of the country will be located just to our SW and typically clusters of storms ride along that boundary. I expect another cluster to develop tomorrow night, supported by a mid-level vort max and a warmfront at the surface, we should see showers and thunderstorms first thing Wednesday morning. Those storms will have very heavy downpours, lots of lightning too. There is question as to how far the warmfront gets because of a wave of low pressure developing along it somewhere in Southern NE…places south of the front will warm into the 80s and north of the front will stay in the 70s. Along with the 80s hazy sun will break out and destabilize the atmosphere once again so the final placement is critical but right now we have to assume that most of Southern NE will see some hazy sun and therefore the warmer temps with the end result leading to more thunderstorms. The afternoon and evening storms could be quite strong with damaging wind and hail. Any storms that develop appear to be fast movers and should be fading shortly after sunset.
The one fly in the ointment and a potential obstacle for later in the evening and a second shortwave diving down from the north. The vort could, and I stress could, prolong rainfall through the night in one of two ways. First, any dying storms could collapse into a steadier area of rain that would be very slow moving and even though the lightning would be gone, rain is never good for outdoor firework viewing and parties. The second way rain could be a player later in the night is that second vort could strengthen the developing surface low along the warmfront and cyclonic flow along with the incoming lift from the vort could produce a lingering area of rain especially along the coast…also not good. Again, these are worst case scenarios, but ones we will be evaluating through the next 24 hours as we fine tune the fourth forecast.