Mesoscale Discussion 0631
NWS Storm Prediction Center Norman OK
0132 AM CDT Sun Jun 03 2018
Areas affected...southeast Arkansas...Mississippi...and far western
Concerning...Severe potential...Watch possible
Valid 030632Z - 030830Z
Probability of Watch Issuance...60 percent
SUMMARY...Organized cluster of thunderstorms across far eastern
Arkansas and northern Mississippi will continue to quickly move
south-southeast. Strong, gusty winds will be possible with this
cluster for the next few hours.
DISCUSSION...Long-lived thunderstorm cluster, with history of
producing wind damage, is moving quickly south-southeast across far
eastern Arkansas and northwest Mississippi. Radar inspection of this
thunderstorm cluster suggests it has developed internal
structure/organization, including rear-inflow jet, supportive
potentially strong surface winds for at least the next few hours.
Extrapolation of current storm motions/trends suggests this
thunderstorm complex will arrive in the I-20 corridor in the next
2-3 hours. Additionally, thunderstorm intensity has increased with
a thunderstorm/thunderstorm cluster across northeast Mississippi.
00Z JAN sounding, along with recent mesoanalysis data, suggests
effective bulk shear around 30 knots and a sufficient CAPE reservoir
to maintain ongoing thunderstorms.
Biggest question regarding severe potential centers around the
thunderstorm clusters' ability to bring the strong winds downward
through an increasingly stable nocturnal boundary layer. An
increasingly hostile low-level environment (such as decreasing
low-level lapse rates, increasing convective inhibition) should
decrease the ability to mix down strong winds. However, the ability
of current thunderstorms to produce wind damage suggests the ability
to overcome this detriment and a severe thunderstorm watch is
currently being considered.
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 33509128 34379106 34988895 33828800 32818840 32159015