Brighter yellow shows thicker clouds.
Coarse, sandy soils, as in the desert southwest and High Plains, may appear mottled yellow, even with clear skies. Dark blue shows thicker cirrus. May also be associated with extremely cold surface temperatures in winter. The depth estimates are not valid for multiple cloud layer conditions. Some areas of IFR may not be detectable by the GOES product due to insufficient thickness, obscuration by cirrus, or insufficient temperature data.