The storm I started talking about last week is now fully developed and just beginning to move towards the eastern US , this storm will bring rapidly increasing clouds tonight , and a gradual increase in both winds and chances of rain as we go through late tonight for southern areas , to tomorrow night for northeastern areas of the forecast area , winds will begin to increase out the east tonight and tomorrow with generally 15-25 mph ENE winds by tomorrow afternoon with gusts up to 35 , winds will gradually shift to the southeast as a warm front slowly makes its way through Wednesday into Thursday.
The pattern is setting up just right for a major potentially flooding rainstorm , now we look at the radar and it appears that rain is already rapidly filling in, however if you look at the water vapor you see a big counter clockwise spin to our north and east , this is a block developing which will force the whole set up to slow down rapidly overnight and this block will prevent any significant rain from filling into a good chunk of the area until late tomorrow afternoon or tomorrow night even.
The rain showers will have no problem spreading into the Washington DC metro through the Philadelphia metro by later tonight and earlier tomorrow but north and east of there its going to take longer for the rain to spread in with this block setting up, of course though once the rain starts in your area it wont be stopping for a while.
So tomorrow will be cloudy for all with increasing winds, a showery and rainy day is expected for the Philadelphia metro, SE PA , SNJ and the Delmarva area , places like NYC and CT along with Central NJ points northeast look to be mostly dry tomorrow with just a few light showers possible , temperatures will be very cool everywhere with the easterly flow with temperatures generally in the upper 40s to mid 50s for highs
By tomorrow night the showers will become widespread and spread northeast gradually becoming heavier by early Wednesday for everyone as a warm front approaches , the main low will be stalling around the Great Lakes and the warm front will only very slowly pass through , leading to slowly developing steady moderate to heavy rain by early Tuesday evening for southern areas, and mid Wednesday morning for NYC area points north-east
Wednesday will be a very chilly day Philadelphia points north as the easterly slow continues with many areas struggling to break out of the 40s , gusty east winds and steady rain can be expected area wide , as the warm front passes by and a cold front basically is either stalled or very slowly crawling eastward, along with an established southwesterly flow flow from the Gulf of Mexico up the east coast and even a easterly flow from the Atlantic, heavy thunderstorms will become possible by Wednesday night through Thursday afternoon , this is when the most rainfall is expected as of now and flooding and flash flooding will become a concern area wide.
While flooding is the main concern some storms could reach severe levels , especially for southern NJ. Philadelphia points southwest with damaging winds possible, temperatures will also rapidly rise with 60s and low 70s expected for most of the area Thursday besides Connecticut where the easterly flow may never turn southerly
The rain will slowly become more showery in nature Thursday afternoon and evening although isolated to scattered showers will be a threat through Saturday, the bulk of the rain will fall by Thursday afternoon.
By Friday and Saturday there could be some peeks of sun but mostly cloudy skies and isolated to scattered showers will still be possible with highs falling back towards the mid 50s to low 60s and lows in the 40s area wide
Total rainfall around the area is generally expected to be 3-5 inches for most , there could be a tight gradient over CT with the way the block is forming, where northeast parts of the state may be limited to 2 inches or maybe even a bit less as the block keeps the rain away from you guys the longest , while southern areas of the state could see 3-4 but most of the area is pretty solidly in the 3-5 inch range , the best potential for 5+ inch amounts will be over southern NJ and SE PA into the Washington DC area where the rain will start earlier than elsewhere .
The storm will totally clear out by Saturday evening most likely but on its heels will be another cold front for early next week which could stall out and dump more significant rainfall , but that’s just skepticism now.