Oops, it doesn't look like 'weather service can predict with any kind of accuracy what will happen in a day' is a national day..

Other days

Hiv Awareness Day

Gallery Day

Special Education Day

African Immigrant And Refugee Hiv And Hep Awareness Day

Cursing Day

Slime Day

Fiancee Day

Tell Ur Crush You Like Them Day

Hannah Day

Blanket Fort Day