Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1119 AM CDT Thu May 23 2024

Valid 231630Z - 241200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS EVENING
AND TONIGHT OVER PORTIONS OF NEBRASKA AND WESTERN IOWA...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
PLAINS STATES...MAINE...AND THE TENNESSEE VALLEY...

...SUMMARY...
Severe thunderstorms are possible today across parts of the Plains,
Tennessee Valley, and Maine.  A concentration of severe winds --
some 75 mph or more -- is expected across a portion of the central
Plains this evening into tonight.

...Northern Plains...
Visible satellite imagery shows strong daytime heating occurring
across much of the central and northern Plains, with southerly
low-level winds drawing moisture northward into the region. 
Dewpoints will only be in the 50s across ND/SD/NE/KS this afternoon
as initial thunderstorms develop ahead of a potent upper trough and
associated mid-level speed max.  These initial storms will be
relatively high-based supercells capable of very large hail and
damaging winds.  A tornado or two is also possible.  As the evening
progresses,  model guidance is in strong agreement that storms will
grow upscale into a fast-moving QLCS with an enhanced risk of
damaging winds across much of central/eastern NE into western IA.

...Southern Plains...
Multiple rounds of thunderstorms over TX during the past 24 hours
have resulted in a complex surface pattern, with pockets of
low-clouds and more stable air.  This tends to limit the confidence
in where robust thunderstorms will form later today.  Two areas of
concern are 1) western OK/northwest TX along the dryline, and 2)
central/north TX in vicinity of remnant outflow boundaries.  In both
areas, very large CAPE values and favorable vertical profiles will
favor supercell storms capable of very large hail, damaging winds,
and a tornado or two.  Considered adding an small ENH to western OK,
but there wasn't sufficient confidence on where to place it.

...Maine...
Thunderstorms are beginning to develop along a cold front extending
from NH into Quebec.  Strong heating is occurring ahead of the front
across ME, where a few severe storms are possible later today.  See
MCD #909 for further details.

...TN Valley...
Strong heating is ongoing across parts of middle/east TN and central
KY.  Dewpoints near 70F will likely lead to a cluster of
thunderstorms this afternoon.  Forecast soundings show sufficient
westerly flow aloft and steep low-level lapse rates to pose a risk
of damaging wind gusts and hail in the strongest cells.

..Hart/Wendt.. 05/23/2024

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Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1221 PM CDT Thu May 23 2024

Valid 241200Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHEAST
TEXAS ACROSS PARTS OF THE MISSISSIPPI AND LOWER OHIO VALLEYS AND TO
SOUTHERN WISCONSIN AND LOWER MICHIGAN...

...SUMMARY...
Severe thunderstorms capable of damaging gusts and large hail are
possible from southern Lake Michigan across the Mid Mississippi and
Lower Ohio Valleys on Friday. Damaging gusts and very large hail
also will be possible across parts of southeast Oklahoma and the
ArkLaTex area.

...Synopsis...
On Friday, a shortwave trough will move from the northern Plains
into western Ontario, with a southern lead wave pivoting across the
upper MS valley and Great Lakes. A surface low will move north out
of MN, with a cold front extending south from IA into MO and toward
northern TX by afternoon. A very moist air mass will remain ahead of
the cold front, resulting in an expansive instability field to the
east, with corridors of severe wind and hail expected.

...Mid/Upper MS Valley toward southwest Lower MI...
Thunderstorms are likely to be ongoing from MN southward to perhaps
northern MO, and possibly in concert with the previous nights MCS.
Heating east of the cold front and any ongoing activity will lead to
moderate destabilization, favoring either a continuation of damaging
wind threat or providing foci for later development along outflows. 

Shear profiles will be most favorable for supercells over eastern
IA/northern IL into southern WI where a warm front will enhance
low-level shear. Cells that develop here may produce a couple
tornadoes, assuming storm mode is not linear.

Farther south into MO and IL and IN, the large instability field
will support any MCS that forms during the heat of the day, with
localized areas of wind damage expected.

...Northeast TX into AR/Mid South...
Isolated supercells will be possible anywhere along the front where
heating can remove the cap. Scattered large storms producing hail
and locally damaging winds are anticipated as the air mass will be
very moist and unstable. Low-level winds will be weak but moderate
mid to high level winds should aid storm organization and hail
potential. 

Otherwise, ongoing storm clusters cannot be ruled out over much of
the area from southern MO into AR and TN, and these would likely
persist east/southeastward across the broad and unstable air mass
with damaging wind corridors.

..Jewell.. 05/23/2024

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