The most recent violence has left 12 dead and at least 38 injured.
“four or more people are shot or killed, not including the shooter.”
The holiday weekend nine were killed and more than 60 were injured in attacks fitting that description.
Earlier in the day, a shooting in Philadelphia left two women dead and two others injured.
As Americans debate the possibility of new gun regulations in the wake of the horrific Uvalde school attack, gun violence continued unabated with the official start of summer, June 21, and its hottest nights still ahead.
Two people were killed and two others injured in a shooting at a nightclub, NBC affiliate KPNX of Phoenix reported.
"One month ago it was New York, Texas and California. This weekend it’s Pennsylvania, South Carolina and Tennessee.
In a post on Twitter, Chattanooga Mayor Tim Kelly expressed anger and frustration over the incident.
The president and first lady Jill Biden visited Uvalde on Sunday, meeting with first responders and the families of those who lost children in the deadly shooting