An active weather pattern will take shape for the end of the week into early next week.
Primary concerns for the Pine Belt in Mississippi are for the threat for severe weather from late Friday through Friday night, and then perhaps a new round of storms/heavy rainfall affecting mainly southern portions of the forecast area as we go into Monday. Following that, drier but significantly colder air is expected as we go into mid week.
Concerning severe weather potential from late Friday through Friday night – a powerful storm system is expected to develop over the central CONUS and approach the Pine Belt as we go through Friday. As previously described, the airmass will initially be capped with a strong elevated mixed layer being maintained above increasingly moist lower levels, but a strong split upper level jet will enhance upper level divergence/ascent over Arkansas, and the resulting pressure falls/moisture transport is expected to help erode the cap and increase convective instability sufficiently for deeper convection/storms to develop over mainly the upper Delta region by late Friday afternoon. At this time, better instability will be west of the Pine Belt, and while deep layer shear will support a few severe storm clusters and
supercells suggested by some of the recent CAM guidance, relatively weak low level shear/instability will be limiting
factors for greater tornado potential.
The initial round of ascent will move out during the evening with additional lift developing over most of the Pine Belt as the primary trough axis pushes east across the region, with perhaps a more enhanced area storms affecting southern portions of the Pine Belt area associated with a separate smaller southern stream trough. Similar limitations, particularly with low/mid level lapse rates should continue to keep this from being a more significant event, but it should be noted that on the synoptic scale, this set-up has an impressive look and will need to be monitored closely for overachieving moisture transport/instability that could increase the severe weather threat.
For early next week, in the wake of Friday night`s trough passage, upstream height falls are expected to eventually buckle the baroclinic zone back to the north and this should allow for a round of elevated shower/thunderstorm activity to develop over roughly the southeast half of the Pine Belt from Sunday.
Models are showing differences with handling of this set-up, and confidence is on the low side regarding QPF, but there is some potential for locally heavy rainfall to develop, although the chance for sfc-based storms is rather low at this time.
For later in the week, there is good agreement in the ensemble guidance for a longwave trough over most of the central/eastern CONUS to allow for a prolonged period of below normal temperatures to occur. At this time, no significant intrusions of arctic air are indicated for Mississippi as global models show the arctic stream digging more into northeastern portions of the CONUS…will monitor for any westward trends of CAA trajectories.
