Cold air, a nor'easter and atmospheric river moisture will bring rain, snow and travel delays to college and NFL tailgates this weekend. See the forecast.
It's still gaining steam and likely to become record strong. Here's how this El Niño is already impacting weather in the U.S., including rain and temperatures.
This was a weird early warping of the polar vortex. It could cool parts of the U.S. later this month, but El Niño will also have a say in the weather pattern.
They can dump snow and ice over large swaths of the country. Here's when and where these larger winter storms usually kick in over the Lower 48 States.