You have not specified a location, so it can only be said that it was a sunny day in some parts of the world and not in other parts.
February 13, 1956 fell on a Monday.
February 13, 1956 fell on a Monday.
May 13, 1956 fell on a Sunday.
June 13th 1956 was a Wednesday.
August 13, 1969 is a Wednesday.
Monday
November 13, 1956 was a Tuesday.
July 13, 1956 was on a Friday.
April 13, 1956 was a Friday.
December 13 1956 was a Thursday.
February 13, 1956 fell on a Monday.
February 13, 1956 fell on a Monday.
May 13, 1956 fell on a Sunday.
The Ernie Kovacs Show - 1952 1956-08-13 was released on: USA: 13 August 1956
The Rosemary Clooney Show - 1956 1-13 was released on: USA: 14 August 1956
To Tell the Truth - 1956 - 1957-08-13 was released on: USA: 13 August 1957
To Tell the Truth - 1956 1957-08-13 was released on: USA: 13 August 1957