Shower (precipitation)

A shower is a mode of precipitation characterized by an abrupt start and end and by rapid variations in intensity.

[1] In a meteorological observation, such as the METAR, they are noted SH giving respectively SHRA, SHSN, SHPL, SHGS and SHGR.

[2][3] Convection occurs when the Earth's surface, especially within a conditionally unstable or moist atmosphere, becomes heated more than its surroundings and in turn leading to significant evaporation.

The raised air parcel in a colder environment at altitude will cool but according to the adiabatic thermal gradient forming clouds, and later precipitation above the lifted condensation level (LCL).

However they can be embedded into a continuous rain episode when there is presence of band of conditional symmetric instability in an otherwise stable air mass.