Storm of Century
(not shown)
930313/1200
Warm
Advection - wind blows from
warmer air to colder
air, acts to build UL
ridge by expanding
air column
Cold
Advection -wind blows
from colder air to
warmer air, acts to deepen
UL trough by contracting
air column
UL
Divergence
L975
Ahrens,
Meteorology Today, 5th Ed.