Hell on Earth: The Vault
This tornadic supercell's vault region -- near the interface between main updraft tower and downshear precipitation area -- was bathed in continuous lightning. The cyclonically curved mid-level bands (middle right) arc inward toward the storm, while the flared, laminar low level cloud deck (lower left) marks the east edge of the main mesocyclone updraft area. The vault of a supercell is an extremely dangerous place! Cloud-ground lightning can be alarmingly frequent there; and it is often completely surrounded by gigantic hail and damaging gusts. [Vault started as a radar term for a bounded weak echo region (BWER), an arch of intense rain and hail above weaker echoes and often corresponding to this visual structure in supercells.] This part of a supercell is also commonly in the path of the mesocyclone and tornado. Go under the vault, and you risk serious injury or death from every weapon in the storm's arsenal. Also common there: "anvil zits," which are fleeting bursts of high-level cloud-to-air filament lightning like those at upper right. Despite its humble beginnings, this storm dropped hail at least 3 inches in diameter and later produced a fat tornado which my crew and I saw while driving north to catch up.
5 SSE Brinkman OK (2 Apr 99) Looking N