Oops, it doesn't look like 'tropical shirt day' is a national day..

Other days

reading

Reading Day
pumpkin

Pumpkin Day
martini

Martini Day
nae nae

Nae Nae Day
pick me

Pick Me Day
artists

Artists Day
self care

Self Care Day
comfy

Comfy Day
gum

Gum Day
nail polish

Nail Polish Day