Maybe they were celebrating the summer soltice?

[Wade]

Two mysterious objects were seen floating above Kansas City. They (probably) weren't aliens - CNN

What was interesting here is that the article brought up two possibilities and both were nixed. So we still have a what is it? Usually the "object" gets explained away but this time?

 

[CasualBystander]

I didn't know anyone used blue/white instrument packages (which are all but invisible).

The balloon would be considerably bigger at altitude.

I'm going with weather balloons on this.

The balloons are normally bigger than this (2 m).

They will continue to rise until they are out of sight.