•The character of the
outward rush of air depends on the low-level wind
shear in the environment ahead of the squall
line.
•In some situations, the
outrush will occur along a large segment of the line
creating a large bow echo 150-200 km long.
•The bow often develops
rotating eddies on either end, which is called
“bookend vortices”.
•Small tornadoes sometime
observed within the northern booked
vortex.