https://www.wfaa.com/article/news/crime/gunman-killed-in-shootout-with-officers-outside-federal-courthouse-in-downtown-dallas/287-f9dec5e2-ffc5-4dde-82be-67def26c41d6
In the video a reporter asked a question about it. The reporter said the shooter had posted on FB saying a storm is coming.
Yes, it looks that way to me.