773
ACUS02 KWNS 221730
SWODY2
SPC AC 221728

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1228 PM CDT Thu May 22 2025

Valid 231200Z - 241200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE CENTRAL INTO SOUTHERN PLAINS...

...SUMMARY...
A few severe storms are expected across portions of the central into
southern Plains on Friday, with large hail and severe gusts the main
threats. More isolated strong to severe storms remain possible
across portions of western Texas and southeast Florida.

...Synopsis...
A mid-level trough will eject into the Atlantic as upper ridging
prevails over the central CONUS and a mid-level trough impinges on
the Interior West tomorrow (Friday). An embedded mid-level impulse
will crest the central U.S. ridge, encouraging surface low
development over the southern Plains. Rich low-level moisture will
cyclonically pivot around the low through the forecast period, with
at least some of this moisture reaching the Colorado Front Range by
late afternoon. Strong to severe thunderstorms should develop over
the central High Plains during the afternoon, with additional
development possible overnight across the central to southern Plains
at the nose of a low-level jet. A few strong storms also remain
possible over eastern parts of the Florida Peninsula along
sea-breeze boundaries.

...Central High Plains (Late Afternoon and Evening)...
By afternoon, southeasterly upslope flow along the higher terrain,
from the Colorado Front Range to the WY/NE border, will advect
adequate moisture that is pivoting northward around the surface low.
At least mid 50s F surface dewpoints, beneath 9 C/km low and
mid-level lapse rates, will contribute to 1000-2000 J/kg MLCAPE.
40-50 kts of northwesterly 500 mb flow from the upper ridge,
overspreading weaker southeasterly flow, will support elongated,
mostly straight hodographs and corresponding 35-40 kts of effective
bulk shear. Storms that form and move off of the higher terrain
should be splitting supercells with mainly a large hail threat,
perhaps accompanied by severe gusts as well. Given such steep lapse
rates through a deep-layer of the troposphere, and elongated
hodographs, 2+ inch diameter hail is possible and a tornado cannot
be ruled out.

...Southern High Plains (Late Afternoon and Evening)...
By afternoon peak heating, robust mixing within the boundary layer
will encourage the eastward advancement of the dryline over western
TX. Resultant low-level convergence along the dryline will support
the development of high-based storms atop a surface airmass with mid
90s/upper 50s F temperatures/dewpoints. 8-9 C/km lapse rates through
most of the troposphere will boost MLCAPE to 3000 J/kg, while
gradual veering with height of the vertical wind profiles supports
over 35+ kts of effective bulk shear. Isolated multicell complexes
should develop, and given poor low-level shear and high evaporative
cooling potential, these storms should be outflow dominant. A couple
instances of large hail may accompany the stronger storm cores at
the beginning of their life-cycles, followed by the potential for a
severe gust or two when cold pools/outflow becomes dominant. Storms
should diminish during the evening as the boundary layer stabilizes
and the dryline retreats westward.

...Central into the Southern Plains (Overnight)...
Considerable amounts of convective inhibition should be in place
across much of the central into southern Plains tomorrow afternoon
and evening, casting doubt on the persistence of the central High
Plains supercells into this region overnight. However, even if the
High Plains supercells dissipate, additional storm development is
likely overnight. A 40-50 kt southwesterly low-level jet, centered
at about 850 mb in altitude, is expected to develop over the
southern Plains, with the terminus positioned over southern KS
between 00-06Z. Elevated storms should develop along the terminus,
atop the inversion layer (i.e. above 850 mb). 9+ C/km 850-500 mb
lapse rates and elongated hodographs will support supercell
structures with a large hail risk, though upscale growth into an MCS
is possible, with a continued risk for hail and perhaps a few severe
gusts if a strong enough cold pool can develop.

...Eastern Florida Peninsula (Afternoon)...
By late morning into early afternoon, robust surface heating will
support the mixing and destabilization of a moist boundary layer,
with near 70 F dewpoints beneath 7+ C/km mid-level lapse rates
resulting in 2000-3000 J/kg SBCAPE. The strong surface heating will
encourage the generation and onshore movement of sea-breeze
boundaries, which in tandem with the heating will support
thunderstorm initiation. Modest westerly mid-level flow
overspreading this environment will encourage 30+ kts of effective
bulk shear (modestly elongated, straight hodographs), supporting the
potential for multicellular development, along with an isolated wind
gust/hail threat with the stronger storms.

..Squitieri.. 05/22/2025

$$