From Upton's late morning AFD:
Showers are nearing Orange county and continue to move east into
the early afternoon. A shortwave trough swings across New
England today sending a fast moving cold front into the region.
Have increased PoPs to account for the latest radar trends. Also
have noted rising dew points advecting north from the NJ coast.
CAPE is beginning to increase with the higher moisture and
should reside mainly east of NYC later this afternoon,
supporting a line of low topped convection. Organized lift ahead
of shortwave energy passes to the north, but convergence along
the surface cold front will be the main factor in producing
showers this afternoon/early evening. A few lightning strikes
are possible and due to strong shear, gusty winds and an
isolated severe gust cannot be ruled out. SPC has placed Long
Island and Connecticut in a marginal risk for severe weather.
This line of convection should develop around 20z western Long
Island and southwest CT and quickly sweep through and be
offshore 23-00z. No concerns for any flooding due to the quick
movement of the system.