Outflow, in
meteorology, is air that flows outwards from a storm system. It is associated with ridging, or
anticyclonic flow. In the low levels of the
troposphere, outflow radiates from thunderstorms in the form of a wedge of rain-cooled air, which is visible as a thin rope-like cloud on
weather satellite imagery or a fine line on
weather radar imagery. Low-level outflow boundaries can disrupt the center of small
tropical cyclones. However, outflow aloft is essential for the strengthening of a tropical cyclone. If this outflow is undercut, the tropical cyclone weakens. If two tropical cyclones are in proximity, the upper level outflow from the system to the west can limit the development of the system to the east.