This varies from year to year. The 13th, August, 2010, is a Friday.
August 13 1999 was a Friday.
August 13, 1990 was a Monday.
Saturday
It was a Friday.
August 13, 1963 fell on a Tuesday.
The given date was a Saturday.
The day of the week for August 13, 1983 is Saturday on the 2nd week of August 1983
August 13, 1959, was a Thursday.
13 August 2006 was a Sunday.
August 13 1985 was on a Tuesday.
August 13 1977 was a Saturday.
August 13 2010 was a Friday.