A comparative analysis was made of day of the week variations in homicide and suicide deaths among 15-24-year-old white males, black males, white females, and black females in the 22 counties with the most black persons in the United States. Thirty-seven percent of black Americans and 14 percent of white Americans lived in these densely populated counties. The authors expected a weekend excess of homicide and a Monday excess of suicide. They found a pronounced excess of homicides on weekends, especially among white males. A slight excess of suicide was observed on Monday, but other slight excesses of suicide were also found. Young black males exhibited an unexpected excess of homicides and suicides on Thursday. On Thursdays the black male-white male ratio for homicide was 1.43 and for suicide, 1.26. Possible explanations for the young black males' blue Thursday phenomenon are offered.