After several days of rare solar activity, the National Oceanic and Atmospheric Agency (NOAA) has issued a Severe (G4) Geomagnetic Storm Watch for this weekend. In addition to potential disruptions to power grids, navigation, radio, and satellite operations, NOAA experts predict that the northern lights could be visible across much of the United States, "as far south as Alabama and northern California."

Here's what you need to know about seeing the Northern Lights this weekend and the other potential consequences of a geomagnetic storm.

Before we get into the aurora borealis, let’s talk about the potential geomagnetic storm it could cause. According to Shawn Dahl, a service coordinator at NOAA’s Space Weather Prediction Center (SWPC), two sunspot clusters, one in the Northern Hemisphere and one in the Southern Hemisphere, have been emitting a large number of high-energy solar flares this week.

Currently, the SWPC is monitoring at least seven coronal mass ejections (CMEs) — explosions of plasma and magnetic fields from the sun's corona that can trigger geomagnetic storms if they're aimed at Earth. That's what prompted the agency to issue a Severe (G4) Geomagnetic Storm Watch for the first time since January 2005.