The normalized hourly demand values for the 54 BAs are shown for four different three-day time slices, one from each season. The empty (white) cells were either ‘missing’ or flagged as anomalous. In each panel of the figure, there is an example of the predictor values (red cells) that would be used to predict a given demand value (orange cell). The three days shown are all Tuesday, Wednesday, and Thursday and end on the first hour of Friday UTC. The heatmap color range is scaled the same for all seasons to show the seasonal trends. The daily cycle is visible as well.