We forecasted traffic speeds for each hour of the day for the city of Porto. Figure 6 shows predicted traffic speeds at the city scale (taken at 6 a.m., noon, 6 p.m., and midnight.). The map shows that, spatially, the traffic speed of highways is much higher than that of city roads. Traffic speed is lowest at the center of the city. Temporally, traffic speed is higher at night than at any other time, and traffic speed is lowest during commuting hours (6 p.m. in this map). The red lines in Figure 6 have the lowest traffic speed, revealing areas of traffic congestion.