"It's important for the people of Ashburton to remember the event, to remember all those affected - from victims, staff and other service agencies involved - and to move on and work towards Ashburton becoming the safe place it has always been," Mr McKay said.
The Ministers' Association will speak on behalf of the families. Work and Income will be represented by chief executive Brendan Boyle and the community by the mayor.
Ms Cleveland, 55, was buried in Alexandra on Saturday and Ms Noble, 67, was farewelled at the Ashburton Event Centre on Monday.
Lindy Curtis, 43, who was critically injured in the shooting, is recovering in hospital.
Meanwhile, police have recovered a tablet computer and are continuing to look for a car linked to the man accused of the shootings, Russell John Tully.
A police dive squad continued to search the Ashburton River yesterday.
Divers were looking for any unrecovered personal items that might be related to the investigation, including an additional firearm and ammunition that may have been in the man's possession.
Tully, 48, has been charged with two counts of murder and one of attempted murder and has been remanded in custody.