Mesoscale Discussion 0127
NWS Storm Prediction Center Norman OK
0257 PM CST Sun Feb 23 2020
Areas affected...Parts of the eastern Texas/Oklahoma Panhandle
region...northwest Oklahoma and adjacent portions of southwest
Kansas
Concerning...Severe potential...Watch unlikely
Valid 232057Z - 232330Z
Probability of Watch Issuance...5 percent
SUMMARY...Scattered thunderstorms are expected to continue forming
late this afternoon, with the development of an isolated supercell
or two possible by 4-6 PM CST. This may be accompanied by some risk
for severe weather, but, overall, this threat still appears marginal
in nature.
DISCUSSION...Within lee surface troughing, a surface low appears in
the process of developing and deepening near Liberal KS, with recent
objective mesoanalysis suggesting sustained boundary layer
convergence maximized along a confluence zone to the southeast and
south of this feature, into the Texas Panhandle. This is just to
the east of where boundary layer warming (surface temps into the
lower 70s F) and mixing have become maximized, with associated
destabilization contributing to gradually deepening convective
development the past couple of hours.
Due to weak boundary layer moisture return through the southern
Plains, including upper 40s near 50F across southern/eastern
portions of the Panhandle region, objective analysis and forecast
soundings indicate that mixed-layer CAPE is still very weak.
However, stronger ascent and cooling in the exit region of a
cyclonic mid-level jet streak (50-70+ kt at 500 mb) is expected to
begin overspreading this region, into the vicinity of the surface
low, by 22-00Z. As this occurs, it appears that mixed-layer CAPE
may increase up to around 500 J/kg, contributing to at least some
further intensification of thunderstorm activity.
Although the environment, overall, still appears marginal, the
evolution of one or two sustained supercells appears possible. This
may be accompanied by at least some risk for severe hail and
localized strong surface gusts. Low-level hodographs may not be
particularly large, but an isolated brief tornado might not be out
of the question, mainly in the immediate vicinity of the surface
low, east-southeastward along an effective warm frontal zone into
northwest Oklahoma (north of Gage).
..Kerr/Hart.. 02/23/2020
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...OUN...DDC...LUB...AMA...
LAT...LON 36370121 37170098 37400021 36979947 36419939 35380000
34470046 34110092 34750158 35560147 36370121
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