Heavy rain and embedded thunderstorms could dump 1-2″ of rain
Good afternoon everyone!
An ULL that gave parts of the northern/central plains and great lakes region severe weather early this week, will impact the northeast with heavy rain and embedded thunderstorms today thru friday afternoon. A mid level low right now around lake superior will move NNE towards james bay. As a result a trailing cold front will advance eastward from the ohio river valley to the applachians. This very slow moving cold front is the direct result of the Upper level trough going into a negative tilt, and a pretty vigorous ULL in the atlantic that is blocking this cold front from advancing to the coast.
A very important water vapor image observation here is a moisture gradient via the ULL in the atlantic, and our trough over the great lakes that is setting up over our area. We have plenty of moisture being drawn in via the gulf and the atlantic as well from the surface to the mid levels. Here is the latest moisture transport and precipitable water values currently.
Notice the very high pwat values to our south , and also the direction that the gradients are moving in. This will result in any showers or thunderstorms that do develop to provide very heavy rainfall and flash flooding concerns. The central and Eastern portions of PA and western / central NY will receive heavy rainfall first. These showers and thunderstorms will gradually move east through the evening and overnight hours. Most locations today from central jersey , CT , LI and points NE will remain dry. The hudson river valley , and areas around NYC metro along with the jersey coast should start to see rainfall later this evening. The weekend quite frankly is not looking all that great especially the further east you are over the region. The cold front will stall along the coast tomorrow night and saturday. This will result in showers for the region especially over eastern LI , CT , and eastern New england.
I should note that most thunderstorms will remain below severe levels especially with a SE wind in place bringing in a relatively more stable air mass. The biggest threat here is the chance of localized very heavy rainfall and flash flooding. The latest precip amounts via the WPC
Thursday graphic , the heavy rain moves in from west to east , the weekend especially for far eastern sections looks a bit shaky
Questions / comments you can always get me at SteveGwx on twitter
have a great day!