El Niño has far-reaching impacts on weather. In the U.S., it typically brings cooler, wetter winters to the southern states and drier, milder winters to the northern regions. This is due to changes in the jet stream, a high-altitude wind current that influences weather systems. The altered jet stream can lead to increased rainfall and flooding in the southern U.S., while the northern states may experience less snow and warmer temperatures. These changes can also affect hurricane activity, often reducing the number and intensity of storms in the Atlantic while increasing storm activity in the Pacific.