Westerly wind speeds in the polar vortex for the 2023-24 winter (dark blue line). The season has been active, with at least 2 disruptions (dips below the zero line, which mean that the prevailing west-to-east winds at 60˚North have reversed directions). The exact count won't be known until later in the spring. For example, the forecast (light magenta line) says that the vortex will recover from the most recent breakdown. If it does not, then the event will be counted as the "final warming," which is the normal end of each season, not an in-season breakdown. NOAA Climate.gov graph, adapted from original by Laura Ciasto.