Radar signatures#radar#supercell#hail

BWER — Bounded Weak Echo Region

Also: BWER · vault

At a glance

A pocket of *weak* radar return sitting inside an otherwise intense storm — the updraft is so strong it's holding precipitation aloft.

Deep dive

A BWER (a.k.a. the 'vault') is a 3-D feature: a column of low reflectivity bounded above and laterally by high reflectivity. It appears when an intense updraft carries small hydrometeors high into the storm before they can grow into detectable sizes.

BWERs correlate strongly with supercells and giant hail. On a volumetric radar scan, look for a clear area on the inflow side of the storm below a 50+ dBZ core at mid-levels.