Plain English Meaning

Clouds being pushed sideways by the wind from one place to another. An automated weather sensor on the ground can only see clouds that drift directly over it, so clouds moving past off to one side may be missed in the report.

Full Definition

The horizontal movement of clouds across an area, carried by the prevailing wind. In automated weather observing systems, cloud advection is a recognized limitation because the sensor only detects clouds passing directly overhead, not clouds that may be visible nearby but are being blown across the area without crossing the sensor.

Context Anchor

Seen in automated weather observing discussions, especially where a ground sensor reports clouds as they pass over the airport.

Derivation

Advection comes from the Latin advectio, meaning 'to carry toward.' In it is used for any horizontal transport by the wind, whether of , , or — as here — clouds themselves. Knowing this helps separate advection (sideways movement) from (vertical movement).