MD 2227 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR PORTIONS OF THE CENTRAL/EASTERN TX PANHANDLE THROUGH NORTHWESTERN OK.
Mesoscale Discussion 2227
NWS Storm Prediction Center Norman OK
0343 AM CDT Wed Oct 04 2023
Areas affected…portions of the central/eastern TX Panhandle
through northwestern OK.
Concerning…Severe potential…Watch possible
Valid 040843Z – 041115Z
Probability of Watch Issuance…40 percent
SUMMARY…Through the remainder of the pre-dawn hours, increasing
thunderstorm coverage and intensity is expected to spread across the
discussion area from the TX Panhandle into northwestern OK.
Sporadic large hail is possible, and isolated gusts near severe
limits cannot be ruled out.
DISCUSSION…Surface mesoanalysis shows a cold front from central KS
south-southwestward across the northwesternmost part of the main
body of OK, then west-southwestward as a temporarily quasistationary
boundary to a low over the northern Panhandle near DUX. The cold
front continued southwestward from there to east-central NM. An
outflow boundary was drawn ahead of the front across north-central/
northwestern OK, moving south-southeastward about 15 kt but
decelerating, and likely to become quasistationary over north-
central/northwestern OK in the next few hours. Along and ahead of
the front, a narrow plume of favorable low-level moisture was
evident, manifest at the surface as low-mid 60s F dewpoints.
Available GPS-derived data and modified RAP soundings suggest around
1.25-1.5-inch PW near ICT, gradually diminishing to around 0.75-1
inch over the north-central Panhandle. This will be maintained by a
corridor of southwesterly 25-35-kt flow near 850 mb for a few more
hours, diminishing after about 12Z due to the diurnal coupling
cycle.
In the meantime, IR satellite and radar imagery indicate widely
scattered young convection of varying depths, including a couple
thunderstorms, building in the central Panhandle roughly between
AMA-HHF. This activity is growing south of the surface frontal
zone, near the eastern rim of increasing large-scale ascent related
to a shortwave trough over the Four Corners region, and the western
part of the favorable low-level moisture field. Modified 00Z AMA
RAOB and forecast soundings indicate this activity is mostly
elevated above a shallow layer of diabatic, nocturnal near-surface
stabilization, and should remain so as it moves east-northeastward
to northeastward and interacts with the top of the outflow pool
along and north of the prefrontal boundary. 25-40-kt effective-
shear magnitudes and MUCAPE around 1500-2500 J/kg suggest a
parameter space favorable for storm-scale rotation and large hail
from the most intense cells. Given the fairly shallow nature of the
near-surface stable layer, isolated strong-severe downdrafts also
may reach the surface.
..Edwards/Thompson.. 10/04/2023
…Please see www.spc.noaa.gov for graphic product…
ATTN…WFO…OUN…AMA…
LAT…LON 35330017 35160136 35280187 35890197 36180170 36480005
36879864 36509788 35629863 35330017
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