Baroclinic - A state of the atmosphere in which isotherms intersect isobars. The geostrophic wind results in temperature advection, and hence disturbances modify with time. Short waves are baroclinic and therefore modify. Barotropic - A state of the atmosphere where isotherms are parallel to isobars. No temperature advection occurs.
Long waves are barotropic.
Bright band - In radar, indicates the melting point of a snowflake. High intensity return is caused by the water surrounding the ice crystal, hence appearing large. With the wind at your back, low pressure is to your left in the Northern Hemisphere. CAPE - Convective available potential energy. Cirrus - A cirriform cloud composed of ice.