Bounded weak echo region
Videos
The bounded weak echo region, also known as a BWER or a vault, is a radar signature within a thunderstorm characterized by a local minimum in radar reflectivity at low levels which extends upward into
BWER associated with a tornadic supercell in 2006, as seen from different elevation angles. The lower angles (upper left) shows a weaker area of reflectivity but not at higher levels.
Mesocyclone
Videos
A mesocyclone is a meso-gamma mesoscale region of rotation, typically around 2 to 6 mi in diameter, most often noticed on radar within thunderstorms. In the Northern Hemisphere, it is usually located
A mesocyclone (at left) in the Central Zone of the city of Piracicaba, in southeastern Brazil, on January 28, 2025
Supercell diagram with the mesocyclone rotation in red
Mesocyclones are sometimes visually identifiable by a rotating wall cloud like the one in this thunderstorm over Texas.
A tornado developing under a wall cloud within a mesocyclone near Falcon, Colorado