Plain English Meaning

SCT means there are clouds covering between about a third and a half of the sky at that height. It is not a solid layer — there are clear gaps between the clouds.

Full Definition

In a METAR, SCT is a sky cover code indicating that clouds cover three-eighths to four-eighths (3/8 to 4/8) of the sky at the reported layer. It is reported with the height of the cloud base in hundreds of feet above the airport, for example SCT040 means a scattered layer with bases at 4,000 feet AGL.

Context Anchor

Seen in METAR cloud reports, often followed by a three-digit height group, such as SCT025.

Derivation

From the everyday word 'scattered,' meaning spread out with gaps between. The aviation use keeps that idea but pins it to a specific fraction of the sky — 3/8 to 4/8 covered.