MD 0207 CONCERNING SEVERE POTENTIAL…TORNADO WATCH LIKELY FOR PORTIONS OF FAR SOUTHEASTERN OK INTO AR…SOUTHEASTERN MO…AND FAR WESTERN TN
Mesoscale Discussion 0207
NWS Storm Prediction Center Norman OK
0106 PM CST Sun Mar 06 2022
Areas affected...Portions of far southeastern OK into
AR...southeastern MO...and far western TN
Concerning...Severe potential...Tornado Watch likely
Valid 061906Z - 062130Z
Probability of Watch Issuance...80 percent
SUMMARY...The threat for a few tornadoes, damaging winds, and
isolated large hail should increase this afternoon. Tornado watch
issuance is likely in the next couple of hours.
DISCUSSION...Showery convection has persisted for much of the day
across eastern OK into northern/central AR, likely related to the
continued lift associated with a 25-35 kt south-southwesterly
low-level jet. A shortwave trough over the Southwest and adjacent
southern/central High Plains will eject northeastward through this
evening. Large-scale ascent over AR and vicinity is expected to
remain nebulous in the near term. Still, it appears increasingly
likely that sustained, surface-based storms will develop by 21-22Z
(3-4 PM CST) as continued diurnal heating and low-level warm
advection aid parcels in reaching their LFCs, and as a pronounced
inversion around 670 mb observed on the 12Z LZK sounding slowly
erodes.
These storms will have access to rich low-level moisture to the
south of a cold front, with surface dewpoints generally in the low
to mid 60s. MLCAPE around 500-1250 J/kg will support surface-based
storms. Even though low-level flow is not overly strong early this
afternoon, it is forecast to quickly strengthen by late afternoon
and especially the early evening as the shortwave trough approaches
from the west. Marginally favorable hodographs for updraft rotation
around 21-22Z should increasingly become more elongated/curved
through 02-03Z in the boundary layer. With the low-level jet likely
strengthening to 45-50+ kt in this frame, the corresponding increase
in low-level shear should prove favorable for a threat for a few
tornadoes late this afternoon and evening. Some of these tornadoes
could be strong with effective SRH of 200-300+ m2/s2, especially
with any supercell that can remain discrete ahead of the cold front.
Isolated large hail may also occur with any of the initially
discrete convection, as 40-50 kt of deep-layer shear will be
favorable for supercells. Later this evening, damaging winds may
become more of a concern if storms can grow upscale into one or more
small bowing clusters. Given expectations for a gradual increase in
the overall severe threat this afternoon, a Tornado Watch will
likely be needed in the next couple of hours.
..Gleason/Hart.. 03/06/2022
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...PAH...MEG...LZK...SGF...SHV...TSA...
LAT...LON 34069483 34639517 35129491 35919375 36639136 36919031
36978977 36718943 36148939 35658972 35479007 34739159
33879315 33629389 33729446 34069483
