Forecast Discussion
SPC AC 020630
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0130 AM CDT Tue Apr 02 2019
Valid 041200Z - 051200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER
MS VALLEY...
...SUMMARY...
Severe threat is expected to focus across the lower Mississippi
Valley Thursday.
...Lower MS Valley...
Low-latitude short-wave trough that is expected to progress across
the southern Rockies toward the Arklatex region by 04/12z should
deamplify a bit as it ejects toward the southern Appalachians during
the overnight hours. Pronounced day2 lee trough will be dislodged
east to a position from western AR into northeast TX during the
afternoon. This boundary should serve as the focus for potential
severe thunderstorm development as surface temperatures warm into
the mid 70s near the wind shift. Prior to this scenario, early-day
low-level warm advection should focus ascent across the northern
half of the SLGT Risk region ahead of the short wave. Steep
mid-level lapse-rate plume will overspread this region early and
elevated convection that roots atop the boundary layer could produce
hail. Latest model guidance suggests thunderstorm clusters will be
the predominant mode early within the warm advection regime. Ample
shear should support the possibility for at least isolated
supercells. Per earlier reasoning, surface-based thunderstorms may
develop near/just in the wake of ejecting short wave along weakening
surface boundary. This activity would tend to spread southeast
during the evening hours as mean flow becomes more westerly.
..Darrow.. 04/02/2019
