This is a multi-part message in MIME format...

------------=_1537571096-1955-1314
Content-Type: text/plain

ACUS11 KWNS 212304
SWOMCD
SPC MCD 212304
NYZ000-PAZ000-WVZ000-OHZ000-220100-

Mesoscale Discussion 1494
NWS Storm Prediction Center Norman OK
0604 PM CDT Fri Sep 21 2018

Areas affected...Eastern Ohio...western and central
Pennsylvania...western and central New York

Concerning...Severe Thunderstorm Watch 386...387...

Valid 212304Z - 220100Z

The severe weather threat for Severe Thunderstorm Watch 386, 387
continues.

SUMMARY...Mainly a damaging wind threat continues with storms along
a cold front. Gradual weakening is expected as the boundary layer
cools, and storms begin moving into a less heated/more stable
airmass. A wider warm sector in western/central Pennsylvania may
allow for storms with isolated damaging wind gusts to continue east
of Severe Thunderstorm Watch 0386, and a Severe Thunderstorm Watch
issuance downstream may be necessary.

DISCUSSION...Earlier semi-discrete storms have recently congealed
into a squall line, from ROC, down to LCK, with the corridor of
strongest storms (with a history damaging wind gusts) located from
just west of BFD to PHD. These storms have organized in a kinematic
environment characterized by 50-60 knots of bulk effective shear,
with up to 250-300 m2/s2 effective SRH noted in northwest PA into
western NY. Despite the favorable shear environment, the airmass
downstream of the squall line (central PA to central NY) is more
stable, with surface temperatures mainly in the low 70s, owing to a
stratus deck which has limited insolation.

As such, the squall line is expected to traverse a more buoyant
airmass for the next few hours, characterized by surface
temperatures in the lower 80s and MLCAPE up to 1000 J/kg. During
this time, storms may continue to produce damaging wind gusts and
perhaps exhibit transient low-level rotation (given the strong
low-level speed shear in place). Thereafter, a weakening trend is
expected given the cooler temperatures to the east and the
cooling/decoupling of the boundary layer overall.

The buoyant warm sector between the ongoing squall line and a more
stable airmass to the east is narrower in New York as opposed to
western and central Pennsylvania. Storms may continue past the
eastern bounds of Severe Thunderstorm Watch 0386 with at least an
isolated damaging wind threat and an additional Severe Thunderstorm
Watch issuance may become necessary in a few more hours.

..Squitieri/Grams.. 09/21/2018

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

ATTN...WFO...BTV...ALY...BGM...BUF...CTP...PBZ...CLE...

LAT...LON 40098211 40668190 41428057 42487904 43337784 43817645
44247538 43967495 43417492 42097615 41227696 40377816
39947927 39978099 40098211



------------=_1537571096-1955-1314
Content-Type: text/plain; charset="US-ASCII"
Content-Disposition: inline
Content-Transfer-Encoding: 7BIT

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. ------------=_1537571096-1955-1314--

--- SBBSecho 3.06-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)