Severe Weather Impacts Today; TORNADOES & DAMAGING WINDS

…SUMMARY…

Severe storms capable of damaging winds and tornadoes are likely this evening and overnight across the ArkLaMiss region and Tennessee Valley

 

Categorical Outlook

10% Tornado Probability

30% Wind Probability

5% Hail Probability

Simulated RADAR Reflectivity 

…SUMMARY…

Severe storms capable of damaging winds and tornadoes are likely this evening and overnight across the ArkLaMiss region and Tennessee Valley.

   …ArkLaMiss this evening to the TN Valley overnight…

A mid-upper jet streak over the Red River Valley of TX/OK will

progress east-northeastward to the OH Valley overnight, within a

broad cyclonic flow regime over much of the central/northern CONUS.

Cyclogenesis in association with the left-exit region of the jet is

expected from the central Plains to the Great Lakes, and the

influence of the cyclogenesis will extend far enough south to draw

low-level moisture northward today into tonight from the Gulf Coast.

The surface warm sector is confined to southeast TX and the LA coast

as of mid morning, with extensive low clouds to the north in the

developing warm advection regime across the lower MS Valley.

Strengthening low-level flow will result in fairly rapid moisture

transport to the northeast just above the surface today, and will

contribute to elevated thunderstorm development across MO/AR.  The

northeastward progress of the surface warm sector will be slower,

with boundary-layer dewpoints into the upper 60s and at least weak

surface-based buoyancy expected into the ArkLaMiss by this evening.

The initial elevated storms could pose a marginal hail threat into

the afternoon, though the more substantial storms rooted near the

surface are not expected until closer to 00z across northern

LA/southeastern AR.  Wind profiles will become favorable for

supercells (effective SRH 400-600 m2/s2), and assuming sufficient

destabilization with mid 60s dewpoints into middle TN and upper 60s

into northern MS by tonight, there will be a threat for tornadoes,

including a couple of strong tornadoes.  Convection will

subsequently spread northeastward along a cold front and likely

evolve into a QLCS.  Low-midlevel flow of 50-70 kt, large curved

hodographs, and weak buoyancy in a narrow corridor ahead of the

front will support a threat for damaging winds and tornadoes with

embedded circulations into the overnight hours.