Collocations for sunny - adj.

be, look
become, get
remain, stay

brilliantly, very
a brilliantly sunny day

pretty, quite (BrE)
mostly
beautifully, gloriously (esp. BrE), gorgeously
It's gorgeously sunny outside.
a gloriously sunny morning

bright sunny …
It was a bright sunny day.

Sunny is used with these nouns:
afternoon, beach, day, disposition, morning, optimism, outlook, side, sky, smile, spell, spot, temperament, terrace, weather, window, yellow