713
ACUS11 KWNS 231601
SWOMCD
SPC MCD 231601
MEZ000-MAZ000-NHZ000-VTZ000-NYZ000-231730-

Mesoscale Discussion 1382
NWS Storm Prediction Center Norman OK
1101 AM CDT Sun Jun 23 2024

Areas affected...eastern New York...much of Vermont...and western
Massachusetts.

Concerning...Severe potential...Watch likely

Valid 231601Z - 231730Z

Probability of Watch Issuance...80 percent

SUMMARY...A tornado watch is likely by early afternoon.

DISCUSSION...A mid-level jet streak can be seen on water vapor
crossing southern Ontario late this morning. As this spreads east
through the afternoon, expect thunderstorm development along a
pre-frontal trough, which is currently crossing Lake Ontario. A very
moist airmass is present across eastern New York with upper 60s to
low 70s dewpoints. In addition, some heating has occurred between
broken cloudcover with temperatures now in the upper 70s to low 80s.
Some additional heating, combined with cooling temperatures aloft,
should combine to increase MLCAPE from around 500 J/kg as of 15Z to
around 1200-1500 J/kg by 17-18Z. This instability combined with a
favorable supercell wind profile (45-50 knots of 0-6km shear per TYX
VWP) should result in severe storms by early to mid afternoon. Some
hail is possible given supercell storm mode, but the warm lower
troposphere (14kft freezing temps) may limit the hail threat
somewhat. The greater threat is expected to be damaging wind gusts
and a few tornadoes. Veered surface flow is the primary mitigating
factor to a greater/more intense tornado threat given the supercell
storm mode and 170 m2/s2 0-1 SRH (per TYX VWP). However, despite the
somewhat veered surface flow, the low-level jet is expected to
strengthen through the afternoon/evening which will support the
threat.

A tornado watch will likely be issued by 17Z.

..Bentley/Hart.. 06/23/2024

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...GYX...BOX...BTV...ALY...BGM...BUF...

LAT...LON   42467589 42967612 43787610 44687566 45077395 45047157
            44747069 44027010 43537018 43017053 42667056 42227123
            42117211 42077346 42137382 42467589