Mesoscale Discussion 0020
NWS Storm Prediction Center Norman OK
0630 PM CST Fri Jan 10 2020
Areas affected...portions of south-central/southwest Texas
Concerning...Severe Thunderstorm Watch 4...
Valid 110030Z - 110230Z
The severe weather threat for Severe Thunderstorm Watch 4 continues.
SUMMARY...A broken line of thunderstorms, including supercells, has
developed along the dryline from south-central Texas down to Eagle
Pass, TX. Large hail remains the main threat, although damaging
winds and a tornado or two are also possible.
DISCUSSION...Storms are moving northeast but are remaining close to
the dryline with steering flow mostly parallel to the boundary. Hail
sizes of 0.5 - 1.25 inches have been reported. Large hail remains
the primary threat given steep mid-level lapse rates of 7+ C/km and
long hodographs with effective bulk shear of 50-70 knots. Storms
will continue to develop and move northeast near the dryline for the
next 1-2 hours, but will eventually coalesce into a line and move
east-northeast as the upper-level trough ejects out over the Plains.
A tornado or two is possible, especially with any discrete
supercells, although a weak, brief tornado cannot be ruled out when
the squall line forms. Damaging winds are also possible both with
discrete cells and after the line forms. The severe threat will
continue through 0400 UTC across much of the watch, but the severe
threat will diminish from west to east behind the line.
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 28720056 29669939 30389877 30879818 30909717 30829698
30199699 29259727 28379913 28180023 28720056