Tonight: A stray thunderstorm is possible at any time, but the most organized area of rain looks to occur overnight. Most of the state should get at least some rain tonight, with the SE coast POSSIBLY staying dry, depending if there is anything left of the rain by the time it gets that far east. NAM temperatures seem too cool vs. reality. I do realize that if steady rain moves in, the temperature should cool to the dew points, but NAM temperature guidance somehow lowers the dew points despite no real air mass change. Therefore, GFS temperatures will be used. It will be a warm and muggy night, with lows only 70-75 across the state.
Tomorrow: It will still be quite hot, but it will be significantly drier. As is the case with summertime cold fronts, a lot of times the drier air will outrace the cooler air. That, plus a downslope component to the winds should yield high temperatures in the mid to upper 80s. Dew points should fall to 50 to 55, so it will be more comfortable.
Tomorrow Night/Wed: A reinforcing shot of cold air arrives, combined with the possibility of some type of coastal wave developing along a front that will be slowing as it encounters the Bermuda Ridge. High temperatures should only be in the mid to upper 70s on Wed. The NAM does not seem to think any coastal reflection exists. Although I do believe there will be some type of wave, due to thermal differences and slowing of the front (and even without the coastal low we should have some chances for showers), I won't go all in, in deference to the NAM. There also is some question IF there is a coastal wave how far north the precipitation will get. (It is not impossible to see these slip SE, since the front is in motion). Therefore, I think a period of at least light rain is likely for the SW portion of the state, with a chance of a shower or two for the rest of the state. The far NE portion of the state may very well not see any rain at all. Modifications to this forecast could be needed with time.
Long Term (Thu-Sat and beyond): Beautiful summer weather should dominate Thu thru Sat. High pressure of Canadian origin will be in control. This should keep storms, as well as hot and humid weather. at bay. With downsloping winds and plenty of sun on Thu and Fri, I'll go a few degrees higher than guidance high temps, but then a couple degrees lower on Saturday, with increasing clouds and a more onshore component to the wind. This yields highs in the low 80s on Thursday, then trending down a couple of degrees each day, to near 80 Friday and mid to upper 70s on Saturday.
A warm front may trigger a brief shower or thunderstorm later Sat night or early Sun morning. Model guidance currently does not show a lot of precipitation, but you always have to be careful with warm fronts, since they come from moisture-rich sources and tend to bring that air with them.
Sunday looks to be hot and humid, as we'll be in the warm sector and under control of the Bermuda High. Temperatures could be tricky, as it may not be totally sunny. Being so far out and not wanting to try to forecast exactly how much convective debris cloudiness could spill into our area, I'll just go close to guidance on temperatures. Highs should generally be in the mid 80s statewide, except maybe a few degrees cooler in the NW hills.
A strong cold front approaches on Monday. Since most of the precipitation is behind the coldfront (anafront), I wouldn't expect a lot of severe thunderstorms. Even if the timing is not favorable for severe weather, a front with this big of a thermal and isodrosotherms packed that tightly suggests there should, at the very least, be some type of shower and thunderstorm activity accompanying the frontal passage. In addition, with such a strong Bermuda high in place, there's always a chance the front slows down. With clouds and showers around, and a much cooler air mass in place, guidance looks too warm for Monday. In fact, it is entirely possible, if not likely, that most of the state doesn't get out of the 60s on Monday.
The long range looks to turn more stormy in general, especially towards the end of the month and beyond. Temperatures look close to normal, or a bit above normal, perhaps cooling to near or below normal after July 4th or so.
Now, let's take a look at some systems expected to affect our region in the coming week. First, let's take a look at the potential frontal wave for Wednesday evening. On this map, you can propogate the precipitation ENEWard at about 250-260 degrees. You can mark I 84 as a good cutoff line for a few hours of steady, light rain, vs nothing at all.