Everyone clapped at nothing when the sun came back

The thunderstorm in Trinity Bellwoods Park started with no warning on a Sunday afternoon, and a crowd of us packed under the same huge tree. A man began handing out the snacks from his picnic. A student shared a tarp. We stood there for half an hour, shoulder to shoulder, soaked at the edges, while the lightning moved off east. When the sun came back everyone clapped at nothing in particular. I have gone back every Sunday. I have not found the tree. It is very large. It is hiding.