Postrain

Postrain is a term used in meteorology and related disciplines to describe the interval and conditions after a rainfall event. The term combines post- with rain, signaling “after the rain.” In common usage, postrain refers to the short period immediately following precipitation, when rainfall has ceased but residual effects persist. Typical postrain conditions include a cessation of visible precipitation, a tendency for humidity to remain elevated, ground moisture, and changes in surface temperature as skies clear.

In scientific usage, postrain dynamics are of interest for understanding drainage, soil moisture gradients, and the drying rate of surfaces. Researchers may examine postrain temperature changes, dew formation, and the evolution of wind fields as convective systems dissipate. The duration of a postrain phase can vary from minutes to hours depending on climate, terrain, and storm intensity.

Applications and implications: postrain conditions affect agricultural management by influencing disease pressure and irrigation timing, and they influence urban drainage planning and flood risk assessment by informing estimates of surface runoff after rain events. The term is informal and may appear in field notes, forecasting discussions, and climate blogs; more formal terminology often uses post-precipitation or post-rainfall specifications.

See also: after rain, post-precipitation, rainfall, humidity.