For tonight, with a fresh cold frontal passage and low relative humidities, we should be able to radiate effectively. Expect low temperatures to range from 50 to 55 in the coldest locations, to 60 to 65 in the warmest locations.
For tomorrow, expect plenty of sun and cooler temperatures than today, on the heels of the aforementioned cold frontal passage. High temperatures should generally be in the 80 to 85 degree range, except in the upper 70s in the far NW hills.
Now for tomorrow night and Thursday... models vary with the exact track of low pressure system during the day on Thursday. Depending on which model is right, the low could be anywhere from upstate New York to Southern Pennsylvania Thursday morning. This track will have a considerable impact on our weather. Either way, the weather will be unsettled on Thursday and it is not a day you want to be planning outdoor activities. If the low tracks further north over upstate New York and then into Northern and Central New England, expect a squall line of strong to severe thunderstorms with it. If the low tracks right through the NJ/NY border and into Southern Connecticut, a tornado risk would come with it. Finally, if the low tracks through Southern Pennsylvania and through Southern New Jersey, a cool rain would be more likely. I think, at this point, a southern track would be more likely; however, not as far south as the extreme southernmost solutions. Therefore, I'l forecast a chilly rain for Thursday, with some imbedded thunderstorms possible for the far south, but no severe weather. All of that action should remain well to the south. Most of the state should stay in the 60s all day on Thursday, except for a possible rogue 70 degree reading in the far west. Keep in mind, if the storm tracks further north, temperatures could end up much warmer. Timing looks to be from about mid morning to about the evening rush hour for now.
Longer Term: Much of the longer term period is quiet, with the next cold frontal passage and thunderstorm threat not slated until probably next Tuesday. In between, look for lots of sun, with high temperatures mostly in the 80 to 85 degree range, except cooler right along the immediate south coast.
On Tuesday, the next cold front will probably affect the state, with a chance of thunderstorms. Obviously, it's way too far out to speculate on timing and strength of the storms.
A few notes on the long range... Many long range forecasters have been persistent in calling for a hot or very hot summer. I have not. I just don't see the mechanism for getting big, persistent heat into the Northeastern United States. From DC to Philly that might be a different story. Can it get hot, or even very hot, for a few days? Sure, it's summer! But will we get days and days of very hot weather like some summers? I doubt it, because too many things have to change and the clock is now ticking.
The first thing that would have to change is the ridging over the Aleutian Islands. It isn't as strong as it could be in the winter, but no jet feature is ever as strong in the summer as it is in the winter. Ridging in that part of the world creates high pressure over Southeastern Canada, which would favor cooler air in the Eastern United States.
Another thing that would have to change, and this could be even harder to do, would be the placement of the Bermuda-Azores high. Typically, when the Bermuda high flexes its muscle, it sets up shop near Cape Hatteras or Virginia Beach, and the flow around it is Southwesterly. This acts as a heat pump, and brings very hot and humid weather into our area. However, this high is shifted too far north this year- east of Nantucket Island. Positioning like that creates more of a Southerly or Southeasterly flow, which would favor a deep marine layer.
Finally, let's say a heat ridge gets pumping and really bakes Philly and DC. Typically, around the periphery of a heat ridge, a phenomenon known as the "ring of fire"- not the Johnny Cash song- sets up. What this means is that in an almost circular fashion around the heat, hence the term ring of fire, showers and thunderstorms form. So if a heat ridge pumped heat to our south, we'd likely get numerous showers and thunderstorms, which would negate the potential of a very warm air mass.
So can it still be a very hot summer? In meteorology, anything is possible, but the clock is ticking, and this is starting to remind me of forecasts of "vodka cold" that was always ten days away in the winter of 2001-02.
Now, let's take a look at some of the features that will be affecting our area in graphical format. First, here's a look at a model's depiction valid midday Thursday.
Next, I'll give you a long range treat. This map shows the progged pattern at 18,000 feet up (a level where a great majority of our weather comes from), valid Day 11, or July 2.