Plain English Meaning

/SK is a label that says 'what follows is extra detail about the clouds' — usually the type of cloud and the height of the bottom and top of each cloud layer.

Full Definition

In a coded weather report, /SK is a remark identifier that introduces a description of cloud layers as observed from a fixed point on the ground, typically reporting cloud type and the heights of layer bases and tops in hundreds of feet MSL. It appears in the remarks section of certain surface aviation weather reports and pilot reports to give a more detailed picture of the sky than the standard cloud-coverage groups provide.

Context Anchor

Seen in aviation weather reports or weather chart station plots when a reporting station does not include sky-condition information.