See northern lights forecast, how to watch aurora in the U.S. this week

The potential for the aurora activity comes as the sun is near the peak of an 11-year cycle at which these plasma eruptions occur with greatest frequency. The eruptions, known as coronal mass ejections (CMEs), originate from sunspot regions that tend to be particularly active around this solar maximum.

A boisterous sunspot region is pointed at the Earth and began releasing CMEs over the weekend. According to SpaceWeather.com, some of them merged, forming a “cannibal CME,” which could produce a strong geomagnetic storm when it arrives at Earth. Geomagnetic storms are what cause auroras.

Geomagnetic storms are rated 1 to 5 on the G-scale (G stands for geomagnetic), with 5 being the most intense. NOAA’s Space Weather Prediction Center is predicting conditions ranging from G1 to G3 through early Wednesday.

A G3 storm often produces an aurora as far south as the northern half of the United States. Such storms can also have minor effects on power systems and disrupt satellite and low-frequency radio navigation.

In May, a G5 storm hit the Earth, producing an aurora as far south as the tropics. By many accounts, it was the most widespread display in at least two decades.

High-latitude locations such as Alaska, Canada and northern Europe have the best chance to see auroras Monday and Tuesday nights.

Late Monday and toward Tuesday morning, when the geomagnetic storm may be strongest, the lights could extend south toward the midlatitudes.

If the storm materializes as predicted, the lights may be visible into the Midwest, New England and the Pacific Northwest. Spots even farther south, including parts of California, the southern Plains and the Mid-Atlantic, could see a faint glow on the horizon, especially with the aid of long-exposure photography.

However, because forecasting the arrival of CMEs is difficult, the timing of the most intense storm activity could shift.

To follow the intensity of geomagnetic storm activity, consider monitoring the K-index. If and when this index reaches 7 or higher, that’s when auroras in the midlatitudes are most probable.

Best viewing will be where skies are clear and away from city lights. Clouds are most likely to interfere with viewing in the eastern United States and Pacific Northwest on Monday and Tuesday nights. However, even where clouds are forecast, it’s worth taking a peek outside, as there are sometimes unexpected breaks in the cloud canopy.

Because the moon is in its last quarter phase, it will illuminate significantly less than when it was full about 10 days ago.

The chance to see the aurora could extend beyond Tuesday night.

Because a large sunspot region is facing Earth, there is the chance for more CMEs this week.

“The active region is now directly facing our planet and in a great position for Earth directed eruptions,” SolarHam.com, an online resource for space weather and auroras, wrote on X.