We see currently a very amplified weather pattern across the US , a bit of a pleasant shift in the pattern for warm weather lovers this week as the MJO has entered phases 4-5 , we have seen a shift from a ridge in the west trough in the east, to a nice large ridge over the east, trough towards the western US , this upper level ridge has shifted off the east coast which is leading to a southwest flow at all levels of the atmosphere, this flow is transporting a very warm and humid air mass up the east coast
High temperatures in the 80s for most of the area can be expected over the next 2 days , with lows only capable of falling into the low 60s interior to mid to upper 60s elsewhere under this humid air mass , so clearly a summer-like air mass in place.
The only fly in the ointment is pop up thunderstorms , we have some pesky upper level disturbances coming from the southwest ahead of the trough to our west, this combined with the warm humid air mass will lead to the chance for some isolated showers and thunderstorms this afternoon and tomorrow afternoon , yesterday afternoon there was no activity due to an area of sinking air that developed over the region, but on the satellite we see that has shifted to the east of the forecast area, and more moisture is building in today
These threats wont be widespread , most locations will remain dry but if your unlucky enough to get into these showers or storms they will likely be long-lasting and capable of very heavy rainfall , tomorrow as we see the cold front come a little closer the threat for these storms will be a bit better but still nothing widespread , and again tomorrow most areas will see highs 80s , mid to upper 80s will be widespread , low 80s along the New Jersey coast with a bit of Atlantic influence , the south shore Long Island will be the cool spot where temperatures will be stuck in the mid 70s and lows will be in the 60s area wide , for the most part tomorrow will be partly to mostly sunny, just keep an eye to the sky for an isolated storm
It is not until Thursday , especially later in the afternoon that we will see a widespread shower/thunderstorm event as the cold front responsible for the deadly tornadoes and hundreds of severe weather reports in the Plains comes east
Above is tomorrow and we can see for the most part rainfall is scattered in nature and a nice large ridge remains over the east
Also, through a lot of the day Thursday showers and storms will be isolated to scattered in nature, but we see the cold front approaching from the west
The cold front is expected to have its peak impact Thursday evening with a line of rain and thunderstorms, some of these storms could be strong with some hail, strong winds and frequent lightning but given the timing of this the severe threat doesn’t appear to be too big right now, of course with the warm, humid and unstable air mass and isolated severe thunderstorm is possible
There is the threat of this front slowing down or even stalling along the east coast, with such a large ridge over the western Atlantic I like the idea the models are showing here, with this cold front and thus showers and storms lingering around the forecast area through much of Friday , there is also a chance for an area of low pressure to ride this front and enhance the chances for rain through Friday , there could be localized flash flooding in this time period, between Thursday evening and Friday evening , we have to watch to see exactly where this front may stall and if it stalls out , there is potential for widespread rainfall amounts to exceed 2 inches in the period, and potentially up to 3-4 inches total for areas that encounter isolated storms over the next 2 days
The good news is , a powerful Canadian high pressure is expected to come southeast, which should clear the rain and cold front out by Saturday morning and lead to tranquil weather, the bad news is this Canadian air mass is going to be quite chilly considering this weekend is Memorial day weekend and the unofficial start to summer , with highs only in the upper 50s to low 60s NE PA to mid to upper 60s along the coast, lows in the mid to upper 30s NE PA , to lows only in the 40s for the rest of the area, upper 40s along the coast , so clearly this weekend will be more of a barbecue in the back yard type of Memorial day weekend , not the usual “go the beach” type of holiday weekend.