Meanings of brilliant yellows in English

The crisp fall air, the brilliant yellows, or­anges, and reds, the long good-bye to summer.

Forsythias and flaming bushes were in bloom, brilliant yellows and scarlets against the gray background.

It was, again, as if she had opened the door onto Oz-anOz of autumn-tonedTechnicolor: hallucinatorically brilliant yellows, golds, reds, oranges.

These same colourful leaves painted brilliant yellows and reds in reality are actually "zombies", already dead leaves awaiting their ultimate fate -leaf drop.