As summer draws to a close, several states across the U.S. are preparing for an unseasonably cool start to September, potentially influenced by a weakened polar vortex. Meteorological models indicate that much of the United States could experience below-average temperatures in the early weeks of September. This phenomenon is attributed to stratospheric warming events and a negative phase of the Quasi-Biennial Oscillation (QBO), both of which can disrupt the stability of the polar vortex.