The Northern Lights have made their comeback, signaling the onset of summer with a breathtaking show along the U.S.-Canadian border. Here’s how to witness the aurora borealis this week.

The U.S. National Oceanic and Atmospheric Administration’s (NOAA) Space Weather Prediction Center (SWPC) forecasts that the Northern Lights will be observable across northern U.S. states on June 1. This display may persist until June 2, although it will be notably weaker.

As is typically the case, your likelihood of witnessing the aurora increases the farther north you are. The SWPC notes that the Northern Lights could be seen “as far south as New York to Wisconsin to Washington state” on Sunday. Those located near the U.S.-Canadian border might still experience a sighting on Monday if fortune favors them, though the area of visibility for the aurora will have diminished considerably.

This aurora borealis is a result of a coronal mass ejection that took place on the Sun’s surface on Friday. The SWPC issued a serious G4 geomagnetic storm warning on Sunday, with expectations that conditions will downgrade to minor G1 storm levels by Monday evening.

According to the NOAA Space Weather Scales, G4 geomagnetic storms can lead to widespread disruptions in power systems and extended interruptions of radio and satellite navigation. On the other hand, G1 storms might only result in slight fluctuations in power grids and minimal effects on satellite operations. Thankfully, the SWPC’s alerts enable us to prepare for and lessen potential disruptions.

However, auroras produced by G1 geomagnetic storms are not visible in as many locations as those generated by more intense storms. While G4 storms have previously created auroras visible as far south as Alabama and northern California, auroras from G1 storms are generally only witnessed at higher latitudes like northern Michigan and Maine.

How to achieve the best experience viewing the Northern Lights

Simply venture outside at night and look upward. Even if you find yourself slightly outside the expected visible area, it’s worthwhile to take a look, as auroras can be seen from over 600 miles away under ideal conditions. To enhance your chances of spotting the aurora, consider several factors.

The SWPC indicates that the optimal time to view the Northern Lights is between 10 p.m. and 2 a.m., as geomagnetic activity peaks during this timeframe. This period also corresponds to the darkest part of the night, creating a strong contrast that makes the aurora borealis more noticeable.

Observing the aurora borealis from a location with low light pollution will also prove beneficial. Some of the prime spots for viewing the Northern Lights are likely to be Certified Dark Sky Places near the U.S.-Canadian border, acknowledged for their low light pollution levels.

What is the origin of the Northern Lights?

Auroras are the result of activity occurring on the Sun’s surface, particularly solar flares and coronal mass ejections. During these events, substantial quantities of plasma and magnetic fields are expelled from the corona, the outermost layer of the Sun.

These expulsions generate a solar wind that travels through space until it reaches Earth. The duration of this journey varies based on the type of event. Radiation from solar flares can arrive at Earth in as little as eight minutes, whereas winds from coronal mass ejections can take hours to several days.

Once the solar wind arrives at Earth, the planet’s magnetic field redirects most of it back into space. However, some charged ion particles penetrate the magnetic field, moving toward Earth’s polar regions where the field is weakest.

These charged ions react with oxygen and nitrogen atoms, resulting in chemical reactions that produce the stunning colored lights referred to as auroras. Both the aurora borealis and aurora australis occur due to the same mechanism, with the former in the Northern Hemisphere and the latter in the Southern Hemisphere.