Mesoscale Discussion 0796
NWS Storm Prediction Center Norman OK
0556 PM CDT Sat May 25 2019
Areas affected...Portions of the Texas Panhandle into northwest
Texas...western and central Oklahoma...southern Kansas
Concerning...Tornado Watch 242...
Valid 252256Z - 260100Z
The severe weather threat for Tornado Watch 242 continues.
SUMMARY...The severe threat continues for Tornado Watch 0242, with
convection translating eastward, towards the eastern bounds of the
watch. As such, a WW issuance downstream may be needed soon.
DISCUSSION...Multicellular clusters and transient supercell
structures alike, have begun to grow upscale into a more coherent
MCS structure along the Texas Panhandle/Oklahoma border area. The
atmosphere across southern Kansas into north Texas may be
characterized by ample buoyancy (up to 3000 J/kg MLCAPE) and modest
deep-layer shear (bulk effective shear of around 40 knots), but weak
low level shear. ICT, TLX, and FDR WSR-88D derived VAD-profiler
data, and latest RAP forecast soundings all indicate relatively poor
speed and directional shear in the lowest 3-km. The weak low-level
shear will likely impede tornado potential to a degree for the
remainder of Tornado Watch 0242.
While nocturnal strengthening of the low-level jet may boost
low-level shear magnitudes to a degree, convection is expected to
have organized into an MCS by then. As such, continued upscale
linear growth, with damaging wind gusts (most likely with bowing
segments and the most intense water loaded downdrafts) are expected
to present the greatest severe weather threat across this area,
though a few instances of large hail are possible. As the upscale
growing convection translates eastward, a new WW may become
necessary for areas east of Tornado Watch 0242.
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 32940157 37350099 37460022 37599904 37649748 37099674
36169638 34929653 33579807 33149951 32940157