369
ACUS03 KWNS 270731
SWODY3
SPC AC 270730

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CDT Thu Jun 27 2024

Valid 291200Z - 301200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF OH
INTO WESTERN PA AND NORTHERN WV...

...SUMMARY...
Damaging winds and a couple tornadoes are possible across parts of
the upper Ohio Valley and Northeast on Saturday.

...Parts of the Ohio Valley and Northeast...
A mid/upper-level shortwave trough and related surface low are
forecast to move from parts of the upper Midwest into Ontario/Quebec
on Saturday, while a trailing shortwave will move southeastward
across the upper Great Lakes during the evening. One or more MCVs
may move eastward within a belt of westerly midlevel flow from parts
of the Midwest/Ohio Valley into the Northeast. A cold front trailing
from the primary surface low will move eastward across parts of the
Midwest, Ohio Valley, and Great Lakes, and eventually into parts of
the Northeast by Sunday morning.

Rich low-level moisture is forecast to stream northeastward
along/ahead of the cold front, aided by a belt of relatively strong
southwesterly 850 mb flow. Midlevel lapse rates are expected to
remain weak, but low 70s F dewpoints and modest diurnal heating
could support moderate to locally strong buoyancy by mid/late
afternoon, though the influence of early-day convection on
destabilization remains rather uncertain.

Scattered thunderstorms may develop during the afternoon from OH
into western PA, with more isolated development possible along the
trailing front into the lower OH Valley. Deep-layer shear will be
sufficient for organized convection, and a few supercells and/or
organized clusters could develop and move eastward during the
afternoon into the evening, with a threat of scattered damaging
wind. Some tornado threat could also evolve, in the presence of rich
moisture and somewhat favorable low-level shear/SRH.

A Slight Risk has been added from OH into western PA. Some expansion
of this risk area is possible with time, depending on extent of
destabilization farther east, and storm coverage farther southwest.

...Ozark Region into the south-central Plains...
Strong buoyancy is forecast to develop during the afternoon along
the trailing cold front from parts of southern KS/MO into northern
OK/AR. Deep-layer flow is expected to be rather weak, but modest
veering with height may support effective shear of 20-30 kt near the
front. Storm coverage along the front in this region remains
somewhat uncertain, but isolated strong to severe storms will be
possible, with a threat of localized severe gusts and possibly some
hail. A couple stronger storms may also develop within a
post-frontal regime across parts of the southern/central High
Plains.

..Dean.. 06/27/2024

$$