Mesoscale Discussion 0120
NWS Storm Prediction Center Norman OK
0319 PM CST Thu Feb 27 2025
Areas affected...parts of Indiana and Ohio...and far northern
Kentucky
Concerning...Severe potential...Watch unlikely
Valid 272119Z - 272345Z
Probability of Watch Issuance...5 percent
SUMMARY...Damaging gusts and perhaps a couple marginally-severe
hailstones are possible this afternoon across parts of Ohio, eastern
Indiana, and far northern Kentucky. A watch is not anticipated.
DISCUSSION...A 500 mb trough axis is situated over portions of the
Ohio Valley this afternoon with very cold temperatures aloft
(approximately -30 C at 500 mb per RAP analyses). This is atop a
post-frontal air mass with surface dewpoints generally in the upper
30s F, resulting in MLCAPE values of 300-400 J/kg with steep lapse
rates. Convective temperature has been reached in portions of
southwest Ohio, where low-topped convection has been ongoing, and
additional low-topped convection is developing along a weak cold
front across portions of northern Indiana and northwest Ohio.
Given the steep lapse rates, low freezing level, straight hodograph,
and the fact that most or all of the buoyancy is above the freezing
level, a few marginally-severe hailstones may occur. The primary
limiting factors for severe hail is expected to be the low-topped
nature of the convection and slightly marginal deep-layer shear.
Additionally, flow in the boundary layer is not overly strong, with
850 mb winds of approximately 30 kts, but convection may mix that
down to the surface and provide some enhancement to produce a few
damaging gusts. The convection, and therefore the severe threat, is
expected to wane later in the afternoon and evening as storms move
to the east and east-southeast with the loss of diurnal heating.
..Supinie/Gleason.. 02/27/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...PBZ...RLX...CLE...ILN...IWX...IND...
LAT...LON 39168552 39928598 40938617 41238537 41478430 41178300
40718205 40258168 39778163 39458178 39008204 38748242
38568349 38618437 38708486 39168552
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