WEATHER UPDATE: Models shifting around a bit with heavy rains…still on course.
We are going to shift modes a bit here to the short range as the remnants of Tropical Storm Bill make their way toward us. The latest National Weather Service rainfall forecast graphic below is from this morning and the number have been raised to 1.50 to 2+ inches. Note that in the areas in grey there are no amounts shown because this is outside the National Weather Service NY forecast zone and DOES NOT MEAN that no rain falls in that area. This rain will begin late this evening and continue into tomorrow morning before beginning to move away to the east. The issue with tropical systems is that sometimes models can’t pick up the local variability that occurs thanks to thunderstorms and amounts locally can certainly be higher.
Below is the map produced by the National Weather Service which shows a wide area of 2 inch plus rains for almost New Jersey and a small portion of SE Pennsylvania. Big amounts also extend southwestward into Northern Virginia. Also note the sharp cut off that occurs over Northeast Pennsylvania as far as the northern fringe of the 1 inch line. It is a fairly tight area of heavy rain however the models are all fairly close in where the heaviest rains are expected to fall.
The visible satellite picture this morning shows a very well defined circulation at mid levels and even at low levels an intact surface low remains. Much of the rains are near the core of clouds over Kentucky. The low is forecast to move east northeast and should be off the New Jersey coast around 8am Sunday. It should continue northeast from there at a decent clip and that is why we feel confident that weather conditions should improve to some degree. However the cold front with the strong low in Upstate NY will be moving through later in the day and that could produce additional showers in some areas for late afternoon. The heaviest rains however with the tropical low will be done between 9am and noon.
he nam model below from today is still pretty much in line with prior runs. The dark red marks the 2 inches plus area and the brighter reds inside show amount to 2.5-3 inches. This map shows total precip through tomorrow evening. By this time the low is long gone. Weather conditions will improve dramatically on Monday as we go to mostly sunny skies and temperatures in the 80s.