An event or movement in Buffalo N.Y. was mentioned at Monday evening's Elbows Up meeting in downtown Toronto. The information I have is that Americans will gather on the Shoreline Trail Bridge near the Peace Bridge.
Here is an archived link to a Niagara Falls-area "Metroland" story:
“Niagara’s U.S. neighbours putting their ‘elbows up’ for Canada”
See also this local radio station item: www.610cktb.com
N.B. the Elbows Up Toronto meeting was posted to Youtube via this link