ACUS03 KWNS 160735
SWODY3
SPC AC 160734
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0234 AM CDT Thu Jul 16 2026
Valid 181200Z - 191200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE OHIO VALLEY INTO THE MID-ATLANTIC...
...SUMMARY...
Severe thunderstorms will be possible across portions of the Ohio
Valley during the late afternoon and evening hours before moving
southeast toward the Mid-Atlantic overnight. Additional
strong-to-severe thunderstorms will be possible during the afternoon
across portions of the Mid-Atlantic.
... Synopsis ...
The CONUS-wide mid-level ridge centered over the north-central
Plains for much of the past week will have retrograded west by
Saturday and be located across the US and Canadian Rockies. Strong
mid-level westerlies will persist on the ridge's northwest, north,
and northeast periphery. Embedded within the westerlies, a series of
short-wave troughs and smaller-scale vorticity/speed maxima will
move across the Great Lakes and Northeast.
At the start of the forecast period, the main short-wave trough will
be located across central Ontario, with its associated jet streak
located across the Upper Midwest. This feature will dig southeast on
Saturday, ending up in the vicinity of northern New England by
Sunday morning. Ahead of this main wave, the 20260716/00 UTC
guidance suite shows multiple speed/vorticity maxima moving through
the west-northwesterly flow, each of which will be capable of aiding
the development of scattered elevated thunderstorms.
At the surface, a weak surface low should develop Saturday morning
across southern Ontario/the northern Great Lakes. This low will
slowly deepen during the day as it digs southeast, reaching upstate
New York by evening. Ahead of the surface low, southwesterly
low-level flow will transport a very moist airmass northeast into
the Lower Great lakes, with 70F surface dewpoints possible as far
northeast as western New York.
To the southwest of the surface low, a surface cold front will serve
as an initiating boundary for thunderstorms during the afternoon. An
unstable and strongly sheared airmass will be in place by later
afternoon across Ohio northeast into western New York. As
thunderstorms initiate along the front, large hail will be possible
before thunderstorm outflows eventually congeal into one or more
linear clusters posing a threat for damaging winds. This line of
storms will push south and east during the evening and overnight
with a continued threat of strong, damaging thunderstorm winds.
Farther southeast across the Mid-Atlantic, most model guidance
indicates the development of a surface trough to the east of the
Appalachians during the late afternoon. To the east of this trough
axis, temperatures will warm into the 90Fs, although there is some
uncertainty how far north the hot boundary layer will extend. Given
the presence of this surface trough and strong diurnal heating,
several clusters of thunderstorms will be possible during the
afternoon, especially if any of the previously discussed
vorticity/speed maxima can interact with the low-level trough.
Strong, damaging winds will be possible with any thunderstorm
complex during the afternoon. Additional severe potential will also
exist overnight as the remnants of the convection along the cold
front approaches the region. Gusty thunderstorm winds will be the
likely threat with these storms.
..Marsh.. 07/16/2026
$$
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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)