MD 0071 CONCERNING TORNADO WATCH 24… FOR EAST TEXAS…NORTHWEST LOUISIANA…AND PARTS OF SOUTHERN AND CENTRAL ARKANSAS
Mesoscale Discussion 0071
NWS Storm Prediction Center Norman OK
1148 AM CST Wed Jan 18 2023
Areas affected...east Texas...northwest Louisiana...and parts of
southern and central Arkansas
Concerning...Tornado Watch 24...
Valid 181748Z - 181915Z
The severe weather threat for Tornado Watch 24 continues.
SUMMARY...A threat for a few tornadoes, damaging winds, and perhaps
small hail is expected to continue for the next couple of hours
across the watch area.
DISCUSSION...Mixed-mode convection has developed from south-central
Arkansas to east Texas in association with a cold front moving
through the region. A few semi-discrete supercells have developed
slightly ahead of the front in association with low-level warm-air
advection. These should pose the greatest short-term threat for
severe hazards. Current mesoanalysis shows that these storms are
forming along the theta-e nose within an environment characterized
by modest MLCAPE (500-1000 J/kg) and large bulk shear (50-60 kts).
This is supported by recent estimates of 60+ kts 0-6-km shear from
the KLZK VAD. The KLZK VAD also contains substantial low-level SRH
(around 350 J/kg from 0-3 km AGL), most of which is contained in the
lowest layers (300+ J/kg from 0-1 km AGL). This has fostered the
development of a couple semi-persistent low-level mesocyclones, and
an attendant threat for tornadoes. An isolated damaging wind threat
should also exist with these storms.
This favorable kinematic environment is coupled with a destabilizing
boundary layer. Partly cloudy conditions in this region have allowed
for gradual warming, now evidenced by surface temperatures around
70-75 F and dewpoints in the mid 60s F. These conditions should
favor ongoing supercell maintenance (in south-central Arkansas and
northern Louisiana) and continued development of any additional
cells that form slightly ahead of the front (in east Texas).
Somewhat steady low-level mesocyclones should continue to be
supported, particularly if observed storm motions (around 240
degrees at 40 kts) remain several degrees to the left of estimated
Bunkers-right motions.
..Flournoy/Gleason.. 01/18/2023
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LZK...LCH...SHV...HGX...
LAT...LON 34599202 34559181 34369163 34099170 33609189 33119221
32449263 31899301 31469335 30899390 30619445 30559505
30679526 31379500 32299434 32929359 33949304 34359272
34569241 34599202
