I made another heatmap: dance weekends. I took the data from the weekend and festival survey I ran a few months ago, went over it again to pull down a few more band names that have been posted in the interim, and collected locations while I was at it. Then I put them all on a map:

(interactive zoomable version)

Looking at this, there's a giant red blob in the Northeast, but in 2012 I wrote:

Dance weekends are not a major part of contra dance culture in the northeast, but seem to be much more central elsewhere.

What's going on?

Some of it is that the Northeast weekends/festivals aren't branded as "dance weekends": Pinewoods, the Flurry, the Snowball, the Dawn Dance, DEFFA. Some of it is that the weekends that do exist aren't put on by the local dances in a 1-1 relationship: in much of the country the area dance organization runs a weekly/monthly dance and organizes a yearly weekend, but in the Northeast they tend to be separately organized. What else? Or is my impression about the significance of weekend culture just wrong?