rains

Rains are a form of precipitation consisting of liquid water droplets that fall from clouds and reach the Earth's surface. Rain is part of the hydrological cycle, formed when moist air rises, cools, and condensation leads to droplet growth until they become too heavy to be suspended.

Clouds form as water vapor condenses around microscopic particles. As droplets merge and grow, precipitation occurs when their size and fall speed overcome updrafts and air resistance. The rate at which rain falls is described as intensity, typically measured in millimeters of water per hour.

Rain occurs in several patterns such as convective rain from localized thunderstorms, frontal rain along weather fronts, and orographic rain formed as air masses are lifted over terrain. In tropical regions, rains can be intense and frequent, while mid-latitudes often show seasonal rainfall.

Rainfall is measured with rain gauges; total rainfall per day is reported in millimeters or inches. Weather radar and satellite data help forecast rain and track storm systems.

Rain supports agriculture, replenishes freshwater supplies, and sustains ecosystems, but heavy or excessive rainfall can cause floods, erosion, and infrastructure damage. Acid rain, caused by pollutants, can lower pH in soils and waters and harm vegetation.

Rain patterns vary by region and season, and climate variability and change are expected to alter rainfall distribution, intensity, and timing.