re: Severe Weather Moving East Today

quote:

---

A volatile weather pattern continues to be apparent for Friday from
eastern TX/OK into the lower MS Valley. An intense mid/upper
shortwave trough over the southern Rockies into northern Mexico will
intensify as it shifts east into the southern Plains through the end
of the period. Most guidance shows a 100+ kt 500 mb jet streak
spreading across eastern OK/TX after 00z, with a 60+ kt
south/southwesterly low level jet developing over the
Arklatex/Sabine River vicinity by 00z. Guidance varies some in the
development of a surface low, located somewhere from north TX to
northern OK Friday morning. The low will deepen as it shifts
east/northeast across AR to near the MO Bootheel vicinity by
Saturday morning.

While the evolution of the surface low remains a bit uncertain,
strong south/southeasterly low level flow ahead of the low and its
associated cold front, will bring rich Gulf moisture northward
across eastern OK/TX and the lower MS Valley. Upper 60s F to low 70s
F dewpoints over eastern and coastal TX will spread eastward across
LA/southern AR and into MS and southwest AL by 12z Saturday. Atop
this anomalously moist boundary layer, steep midlevel lapse rates
courtesy of an EML spreading east/northeast from the Mexican Plateau
will result in pockets of MLCAPE from 750-1500 J/kg from eastern TX
into LA and adjacent portions of AR/MS where stronger heating is
expected. Further north, where temperatures and dewpoints will be
lower, instability will quickly diminish to less than 500 J/kg into
the mid-MS Valley. Mixed convective mode is likely, with a QLCS
developing in the vicinity of the surface cold front by late
afternoon across OK/north TX. Intense shear will aid in damaging
wind potential and very moist low levels, combined with backed low
level flow/strong SRH, will support mesovortex development along the
line. The QLCS will develop east/northeast through the overnight
hours.

Additionally concerning is any convection that develops across the
warm sector ahead of the front/QLCS. Guidance continues to indicate
that more discrete warm sector development is possible, across parts
of eastern TX into LA. Supercells capable of all severe hazards,
some possibly significant, appear most probable across this area
from late afternoon into the overnight hours.

---