A very wet 48 to 66 hours for some in the Northeast
Meteorologist , Steve Garry
To say we have a tropical air mass in place is an understatement , very high humidity / dew points is creating a ton of low level moisture.
The tropical air mass has been transported by a 850mb & surface warm front right into the mid/north atlantic & into the northeast.
We have a pretty strong cold front to our west that is currently sparking severe storm and flash flood warnings.
This cold front appears to be on schedule to sweep through the northern mid atlantic / northeast by tomorrow morning or early afternoon.
This cold front passage early in the day suggests that instability in the atmosphere will be quite limited , which will inhibit the development of strong/severe storms.
However , one thing this cold front will do is provide very heavy downpours to isolated locations tomorrow leading to flash flooding.
This cold front will eventually stall around southern PA , and southern new jersey leading to the threat of widely scattered showers on through thursday afternoon.
A pretty robust wave of low pressure will form along and ride the boundary layer thursday evening into friday morning.
this wave of low pressure will bring very heavy rainfall into the philadelphia and new york city areas leading to flash flood threats.
with PWAT values or precipitable water values of 1.7 to as high as 2.2 , this rainfall is capable of producing 1-2″ rainfalls an hour.
Not everyone will see this , but those that do keep in mind flash flooding a real threat.
I have some concerns that some model guidance might be suggesting a hot/dry weekend ahead by pushing the boundary a bit too far south.
I am a little skeptical of this and would not surprise me to see a few more showers & storms around for the weekend.
The GFS has a much more quiet / dry / warmer forecast than the EUROPEAN ENSEMBLE does , and i tend to lean towards the euro ensemble because IMO it has a better handle on the pattern & has been the most consistent.
So for the weekend we will see , but don’t be surprised if showers prevail instead of sunshine.
comments or questions greatly appreciated , you can follow me on twitter ( SteveGwx)