Currently: A wave of low pressure over the Eastern Shore of Maryland, combined with various mesoscale boundaries across the region have triggered areas of showers and thunderstorms. For those not receiving any rain, the overall day was not so bad today.
Tonight: Most of the convection is diurnally-driven, so I would expect any thunderstorms to diminish rapidly after dark, although I'd keep just a chance in until around midnight, especially along the south coast, where we're closer to the Long Island Sound breeze boundary. Temperatures are a bit tricky tonight- first, because some areas have seen rain, which has cooled the air, and others have not, and secondly, because it is uncertain how much we'll clear tonight. I don't see any mechanism to clear the skies out so much tonight, so I'll go a degree warmer than the warmest guidance. This yields lows mostly in the mid 60s.
Tomorrow: Not a whole lot going on... there is deep layer marine flow most of the day, which does two things this time of year. First, it keeps temperatures cooler, and secondly, it stabilizes the atmosphere. There is also no real mechanism for a lot of sun tomorrow. I'll go with the warmer guidance sets tomorrow for two reasons. First, models tend to overdo onshore flow's effect on temperatures this time of year, and secondly, because any peak of sun will rapidly raise the temperatures. So I'll call for highs generally around 80, except cooler along the immediate south coast.
Tomorrow Night/Fri: Still not too much going on. Onshore flow will continue, so this will continue to suppress both temperatures and thunderstorm chances. I'll use a guidance split for temperatures, as high-resolution guidance tends to really be too cold in onshore flow, especially that far out. Still, with lots of clouds and a deep marine layer, highs should generally only be in the mid 70s, except maybe a few upper 70s in the CT valley.
Long Term (the weekend and beyond): In summary, it will turn much hotter for the bulk of the long term, as the flow becomes more land-based and the Bermuda Ridge takes over. The best chances for thunderstorms will be in the beginning and end of the period, with something of a lull in the middle.
The dailies- Saturday: Guidance temperatures are generally accepted. Diurnal-based thunderstorms should be scattered about during the day, with some lingering instability. Humidity will be on the increase, with highs in the lower 80s.
On Sunday, it will continue to turn hotter, as the Bermuda Ridge continues to assert itself. Look for high temperatures in the mid to upper 80s. An MCS will dive out of the Great Lakes during the day Sunday. Any thunderstorms in association with this system should hold off until after dark. Partly due to the timing, and partly due to the nature of the instability associated with this system, the NW hills would be favored to see the most action from this system.
For Monday, guidance temperatures again are accepted, which yields upper 80s in all locations, and some locations in the I 91 corridor reaching or exceeding 90! Thunderstorm activity should be pretty quiet, although on a day like this, you can't rule out an isolated storm across the NW hills. One of them just might go strong to severe, as well, given the amount of CAPE in the atmosphere, due to the heat.
Tuesday's temperatures should be very close to those of Monday. I went above guidance by a couple of degrees both days. There really is not much air mass change, but the MOS is cooler, due to climatology having a bigger influence in the algorithm that far out. Wednesday's temperatures should be 2 to 3 degrees cooler than those of Monday, due to the fact that we'll likely see more cloud cover and storminess. A fairly strong cold front approaches Tuesday afternoon. Due to the Bermuda Ridge being so strong, it is likely that this front stalls somewhere over the Northeast US. Therefore, a line of thunderstorms likely affects the state later Tuesday and waves of showers and thunderstorms could continue right through Wednesday.
Long Range musings: There doesn't appear to be any trigger for a huge pattern change in the long range, so I'd generally expect a lot more of the same: temperatures generally normal to above normal, with frequent chances for thunderstorms.
Now, let's take a look at a couple systems slated to affect the region... I'll show Saturday's possible thunderstorms and then a look at early next week, in graphical format. On this map, valid midday Saturday, you can see showers and thunderstorms across New Jersey. They should head toward our area later on. At this time, due to timing, it is unclear how much will survive. However, western sections of the state would be favored.