The location of jet streams shift throughout the year and they are said to "follow the sun" since they move north with warm weather and south with cold weather. Jet streams are also stronger in the winter because there is a large contrast between colliding arctic and tropical air masses. In the summer, the temperature difference is less extreme between the air masses and the jet stream is weaker.
One of the most important impacts of the jet stream is the weather it brings. Because it is a strong current of rapidly moving air, it has the ability to push weather patterns around the world. As a result, most weather systems do not just sit over an area, but they are instead moved forward with the jet stream. The position and strength of the jet stream then helps meteorologists forecast future weather events. In addition, they are important to air travel because flying in or out of them can reduce flight time and fuel consumption. One future benefit of jet streams could be to power airborne wind turbines.
Two main jet streams affect weather in North America.
polar jet stream: between 23,000 to 39,000 feet above the ground; located between 30° to 60° north latitude; has the
strongest winds
subtropical jet stream: between 33,000
to 52,000 feet above the ground; located at 30° north latitude; has lower wind speeds
El Nino is a climate event where a tropical South Pacific ocean current found around the equator and countries of Peru and Chile warms a few degrees. It is a convection current, not a storm. It is one of the largest factors in global weather.
El Nino is Spanish – the boy
El Nino = Peru current – cold current in the south east Pacific