Mesoscale Discussion 0641
NWS Storm Prediction Center Norman OK
0116 PM CDT Sun May 05 2024
Areas affected...Northeast AR...Southeast MO...Northwest
MS...Western TN
Concerning...Severe potential...Watch unlikely
Valid 051816Z - 052015Z
Probability of Watch Issuance...20 percent
SUMMARY...Some threat for locally damaging winds and a brief tornado
will spread northeastward this afternoon.
DISCUSSION...A convectively enhanced shortwave trough is moving
northeastward across the ArkLaTex region this afternoon. A loosely
organized arc of convection is ongoing along the northeastern
periphery of the deeper cloud field associated with the shortwave,
from northeast AR into northwest MS. The southern part of this
convective arc is intersecting a weak, nearly stationary front near
the AR/TN/southeast MO border region.
While midlevel lapse rates are expected to remain weak, diurnal
heating of a relatively moist airmass will support moderate
destabilization with time, especially near and to the east of the
surface front, with MLCAPE potentially increasing to 1000-1500 J/kg.
Some intensification of the ongoing convection into a loosely
organized MCS will be possible as downstream instability gradually
increases. Further heating and steepening of low-level lapse rates
may eventually support potential for localized strong/damaging gusts
as storms move northeastward this afternoon. Also, while convection
may tend to outpace northeastward advance of stronger 1-2 km AGL
flow (noted in KLZK and KSHV VWPs), low-level shear/SRH may become
sufficient to support a brief tornado, especially where storms
intersect the weak surface front.
At this time, the severe threat is expected to remain isolated,
making watch issuance unlikely. Trends will continue to be monitored
for an uptick in storm organization through the afternoon.
..Dean/Smith.. 05/05/2024
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...PAH...MEG...JAN...LZK...SGF...
LAT...LON 35439178 35749225 36239204 36499154 36988993 36618926
35798886 34788869 34128896 33758951 33678971 33729036
33769064 34569077 35109122 35439178