Mesoscale Discussion 1190
NWS Storm Prediction Center Norman OK
0551 PM CDT Thu Jun 18 2026
Areas affected...portions of extreme southern Oklahoma into
north-central Texas
Concerning...Severe potential...Watch possible
Valid 182251Z - 190045Z
Probability of Watch Issuance...60 percent
SUMMARY...An MCS may develop over the next few hours and produce a
severe wind swath. A few gusts exceeding 75 mph will be possible. A
Severe Thunderstorm Watch may be needed once timing of convective
initiation can be better ascertained.
DISCUSSION...A cold front and modified outflow boundary continue to
sag southward along the Red River, where a minimally capped,
extremely unstable airmass resides. South of the Red River, 90-100
F/upper 70s F surface temperatures/dewpoints, beneath 8+ C/km
mid-level lapse rates, supports 4500-5500 J/kg MLCAPE. However,
vertical wind shear south of the Red River remains poor given
stronger mid-level flow displaced farther north, away from the
surface-based airmass.
Towering CU have been noted at the intersection of the modified
outflow boundary/cold front, and the current thinking is that
convergence along these boundaries will eventually support robust
convective development. Rapid cold pool mergers (due to weak
vertical wind shear), amid extreme instability, may support a
burst-MCS, with an initial and intense outflow surge capable of
producing a severe wind swath. Given the weak shear, most severe
gusts will probably remain in the 60-70 mph range. However, gusts
exceeding 75 mph are possible given downdraft water-loading and
subsequent evaporative cooling within an extremely buoyant
environment.
It remains unclear when storms will initiate. However, should storm
initiation and organization becomes apparent, a Severe Thunderstorm
Watch will be needed.
..Squitieri/Smith.. 06/18/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...FWD...OUN...SJT...
LAT...LON 32779981 33469941 33979909 34269877 34389841 34169778
33439716 32439688 31879700 31579735 31489787 31649850
32039925 32779981
MOST PROBABLE PEAK WIND GUST...65-80 MPH
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