ACUS11 KWNS 182150
SWOMCD
SPC MCD 182150
CTZ000-MAZ000-NYZ000-PAZ000-182345-

Mesoscale Discussion 1654
NWS Storm Prediction Center Norman OK
0450 PM CDT Sat Jul 18 2026

Areas affected...Parts of southern NY and northeast PA into far
western MA/CT

Concerning...Severe Thunderstorm Watch 494...

Valid 182150Z - 182345Z

The severe weather threat for Severe Thunderstorm Watch 494
continues.

SUMMARY...A threat for damaging wind, isolated hail, and possibly a
tornado will spread across the eastern portion of WW 494. The need
for downstream watch issuance is uncertain.

DISCUSSION...A small storm cluster with an embedded supercell north
of Binghamton is moving east-southeastward as of 2130 UTC. This
cluster has a history of producing wind damage, while MRMS hail-size
estimates with the embedded supercell have occasionally exceeded 1
inch. This cluster will continue to pose a short-term threat of
damaging wind and perhaps isolated hail in the short term as it
approaches the eastern extent of WW 494.

Downstream, earlier convection and persistent cloudiness has limited
diurnal heating and destabilization, though rich moisture and
temperatures gradually warming into low/mid 70s F have allowed
MLCAPE to rise into the 500-1000 J/kg range. With rather strong
deep-layer shear in place, this modest buoyancy may be sufficient to
maintain ongoing organized storm structures as they move out of WW
494. Poor lapse rates may tend to limit the magnitude of the threat
as storms approach the Hudson Valley, but at least a localized
wind-damage threat may persist. Also, veering wind profiles and
favorable low-level SRH (as depicted on the 18Z ALB sounding and
recent VWPs from KENX) may also support a brief tornado threat
within the effective warm-frontal zone.

The need for downstream watch issuance remains uncertain, and will
depend on trends regarding ongoing storm intensity/organization and
downstream destabilization.

..Dean/Hart.. 07/18/2026

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fjg!7eMjzDbuBfw9GHcIGVG24E1IirZ8EHN8kO1IwFBBSKe6DG1HLrhnQ2oLFJNS5SNnbmG1fEjFRPFiZzFLJwk-F3gJARg$ for graphic product...

ATTN...WFO...OKX...ALY...BGM...CTP...

LAT...LON 42667562 42427392 42297347 42057330 41477306 41167333
41497463 41877592 41977734 42197756 42667562

MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN


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* Origin: capitolcityonline.net * KY, USA (1:2320/107)