Virga

Virga is precipitation that evaporates or sublimates before reaching the ground, often appearing as streaks or wisps extending below a cloud.

Evaporation: The transition of a liquid into vapor from its surface. Raindrops vanish when surrounding air takes up their liquid water.
Cloud: A visible mass of suspended water droplets, ice crystals, or both in the atmosphere. Virga begins as precipitation falling from a cloud.
Dry microburst: A strong downdraft that reaches the ground with little or no accompanying rain. Virga can signal evaporation-driven downdrafts that intensify into dry microbursts.
Virga versus rain shaft: A distinction between precipitation that evaporates aloft and a visible column that reaches the surface. A rain shaft continues to the ground; virga fades before it does.
Sublimation: The direct transition of a solid into a gas without becoming liquid. Ice crystals can disappear directly into water vapor before reaching the ground.
Precipitation: Water in liquid or solid form that falls from the atmosphere toward Earth's surface. Virga is precipitation that fails to reach the surface.
Microburst: A localized, intense downdraft that spreads outward after striking the ground. Dry microbursts are one type of the broader microburst phenomenon.
Drizzle: Light precipitation consisting of numerous small liquid water drops. Drizzle reaches the ground, while virga does not.
Relative humidity: The ratio of water vapor present in air to the amount needed for saturation at the same temperature. Low relative humidity leaves the air able to absorb falling precipitation.
Rain: Liquid water drops that fall from clouds to Earth's surface. Rain can evaporate into dry air and form virga.

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