744
ACUS02 KWNS 171732
SWODY2
SPC AC 171730

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1230 PM CDT Fri May 17 2024

Valid 181200Z - 191200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHEAST INTO THE CAROLINAS...

...SUMMARY...
Isolated to scattered severe thunderstorms appear possible across
portions of the Southeast and Carolinas on Saturday, and parts of
the Upper Midwest. Damaging winds should be the main threat, but
occasional severe hail and a tornado or two may also occur.

...Southeast/Carolinas...
There is still some uncertainty with the placement and intensity of
an MCS that will likely be ongoing at the start of the period
Saturday morning along/near the central Gulf Coast. This convection
will be tied to a mid-level shortwave trough and related 50-70 kt
jet that is forecast to move quickly east-northeastward across the
Southeast and Carolinas through the period. Due to the influence of
prior convection in the Day 1 period, there should be a fairly sharp
gradient of low-level moisture and instability along a convectively
reinforced baroclinic boundary extending from southern AL into GA.

Most guidance suggests the ongoing MCS will continue
east-northeastward over these areas into SC Saturday morning while
posing a threat for mainly severe/damaging winds given the presence
of weak to moderate instability downstream. Modest but sufficient
low-level shear should also be present to support a threat for an
embedded tornado or two. Greater severe wind potential will likely
remain confined along and south of the convectively reinforced
boundary. But, some chance for strong to locally severe
thunderstorms with associated hail and gusty wind threat may also
exist across a broader portion of the Southeast into NC along/south
of a cold front through Saturday afternoon.

...Upper Midwest...
Within broad upper troughing across the northwestern CONUS and
western Canada, a compact shortwave trough should advance
northeastward over the northern Plains and Upper Midwest through the
day. A related surface cold front is forecast to surge eastward
across the Upper Midwest through the period. A narrow corridor of
weak to locally moderate destabilization, with MLCAPE generally
ranging 500-1500 J/kg, should develop through Saturday afternoon
along/ahead of the front from parts of far eastern MN into WI and
the U.P. of MI. A belt of strong mid-level west-southwesterly flow
will accompany the shortwave trough, and contribute to around 30-40
kt of deep-layer shear. Organized thunderstorms should develop by
Saturday afternoon, while posing an isolated threat for both
damaging winds and severe hail while spreading eastward through the
early evening. This activity should eventually weaken through
Saturday evening with the loss of daytime heating.

...Central Plains...
Low-level convergence along the cold front and large-scale ascent
aloft become more limited with southward extent into IA and central
Plains. Some guidance does show convective development across these
regions, including near a surface triple point across KS. However,
the overall severe threat appears too limited/isolated to include a
Marginal Risk at this time.

..Gleason.. 05/17/2024

$$