Question

Explain, in detail, the formation of the negative perturbation pressure center that forces a rear inflow jet without using vorticity arguments.

Answer 1

Damaging winds are known to be associated with a rear inflow jet , which on radar scans is usually marked as a rear inflow notch and/or bow echo . In certain situations, downward pressure perturbation force induced by bookend (line-end) mesovorticies may cause RIJ to descend to the ground and produce strong winds . The most damaging winds tend to be found within a strong lowlevel mesovortex coinciding with RIJ on the edge of the bow echo .

Numerical modeling studies show that the RIJ develops in response to the formation of midlevel horizontal pressure gradients to the rear of the convection the blocking or channeling of ambient flow oriented perpendicular to the combined circulation between “bookend vortices” and the dynamic irrotational pressure gradient . The RIJ in turn supplies cool, dry midlevel air to aid in the production of the convective- and system-scale downdrafts .