433
ACUS02 KWNS 160540
SWODY2
SPC AC 160538

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1238 AM CDT Wed Jul 16 2025

Valid 171200Z - 181200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN
MISSOURI INTO PARTS OF THE OHIO VALLEY...MID-ATLANTIC...AND
NORTHEAST...

...SUMMARY...
Isolated damaging gusts are possible from southern Missouri into the
Ohio Valley, Mid-Atlantic, and Northeast on Thursday.

...Northeast...

A shortwave trough is forecast to extend from southern Quebec to
near Long Island early Thursday. At the surface, low pressure will
track from Lake Huron northeast along the St. Lawrence Valley. A
trailing cold front will develop east across the Upper Ohio Valley
and Northeast during the afternoon and evening. Ahead of the front,
a very moist airmass will be in place, supporting MLCAPE values from
around 1000-2000 J/kg.

While 30-40 kt of westerly flow will overspread portions of the
Northeast, effective shear will remain modest, but sufficient for
isolated organized cells (20-30 kt). The surface low is likely to
remain north of the international border, but the cold front should
provide some focus for afternoon/evening thunderstorm activity.
However, subsidence behind the morning shortwave and possibly some
early day showers and cloud cover could hinder thunderstorm
development initially. As a result storms may develop a bit further
south and east than previously forecast, and the Marginal risk
(level 1 of 5) has been removed for parts of the Upper OH
Valley/Lower Great Lakes vicinity. Storms that do develop across the
Northeast still may pose a risk for locally strong gusts, and closer
to the surface low, a tornado or two.

...Southern MO/OH Valley to the Mid-Atlantic...

A seasonally very moist airmass will reside to the south of the
southward sagging cold front extending from the MO Ozarks into
southern IL/IN/OH. A corridor of strong instability is expected
ahead of the front, aided by 70s dewpoints and heating into the mid
80s to mid 90s. Vertical shear will be much weaker with southward
extent, but any MCVs from prior day`s convection coupled with the
sagging cold front, should provide focused for scattered
thunderstorm development. Thunderstorm clusters will mainly pose a
risk for strong gusts from water laden downdrafts.

Additional storms are expected to develop over the higher terrain of
WV/VA along a surface trough and ahead of the surface cold front. A
similar environment to that further east will exist (high CAPE, weak
shear). Thunderstorm clusters may produce isolated strong gusts.

..Leitman.. 07/16/2025

$$