Probability of Watch Issuance...60 percent
SUMMARY...Scattered severe thunderstorms, primarily capable of
damaging wind gusts, are anticipated this afternoon and into the
evening across portions of New England into eastern Pennsylvania,
southern New York, and New Jersey. Though there is some uncertainty
in the degree of convective organization and evolution, a severe
thunderstorm watch could be warranted later this afternoon.
DISCUSSION...Satellite and radar trends show convection developing
across PA into NY in an environment characterized by moderate
buoyancy (~1000-1500 J/kg MLCAPE) and strong deep-layer shear (40-45
kt 0-6km). Though deep convection has yet to form, it is anticipated
that as daytime heating and mixing continues, the environment will
support strong, organized thunderstorm updrafts.
Given long, straight hodographs and appreciable 0-1 km lapse rates
approaching 8 C/km, along with seasonably high precipitable water
content approaching 2.00 inches, the primary threat will be for
damaging straight-line winds of 55-70 MPH within thunderstorm
downdrafts. Hail or a brief tornado cannot be ruled out with any
stronger, isolated organized convection that occurs, though
low-level shear and mid-level lapse rates do not suggest that they
are likely at this time.