NOAA's Global Ensemble Forecasting System (GEFS for short) predicts that the Northern Hemisphere polar vortex will strengthen to slightly above average wind speeds in early February (heavy magenta line), following a major sudden stratospheric warming on January 16 (where heavy purple line fell below 0 meters per second wind speed). The spread of the individual forecasts (thin magenta lines) remains wide in mid- to late-February. A couple individual forecasts predict another polar vortex reversal and major warming, while one individual forecast predicts record strong winds near the end of the forecast period. Climatology of highest and lowest daily values is from Climate Forecast System Reanalysis. NOAA Climate.gov graph, adapted from original by Laura Ciasto.