Geomagnetic Storm Could Hit This Week: When To See the Northern Lights

The northern lights may be visible as far south as New York and Idaho in the coming days thanks to a geomagnetic storm roiling over Earth.

These aurorae will result from the arrival of a coronal mass ejection (CME) flung out from one of the sun's sunspots, which will spark a geomagnetic storm in our planet's magnetic field and atmosphere tomorrow and the day after.

"A G1 (Minor) watch has been issued for 28 Nov and a G2 (Moderate) watch was issued for 29 Nov due to the arrival of a CME associated with a filament eruption that took off the Sun late on 25 Nov," NOAA's Space Weather Prediction Center said in a Geomagnetic Storm Watch.

Stock image of the northern lights (main) and solar plasma (inset). A coronal mass ejection from the sun is expected to spark a geomagnetic storm tomorrow and the day after. ISTOCK / GETTY IMAGES PLUS

NOAA's Geomagnetic Forecast reveals that G1 conditions are expected tomorrow evening, with G2 conditions enduring into the early hours of Friday morning.

CMEs are huge plumes of solar plasma that have been spat out from magnetically active areas of the sun's surface, usually sunspots.

These giant clouds of solar material and magnetic field are usually but not always associated with a solar flare, but take a lot longer to reach the Earth, traveling at speeds of between 560,000 mph to as fast as nearly 6.7 million mph.

What is a geomagnetic storm?

When a CME collides with the Earth, usually 1–3 days after being ejected, it creates a shockwave as it compresses Earth's magnetosphere.

If the magnetic field of the CME is oriented in a way that opposes Earth's magnetic field (southward-directed), a process called magnetic reconnection occurs, which allows energy and particles from the CME to penetrate Earth's magnetic defenses—triggering a geomagnetic storm.

During the geomagnetic storm, the charged particles of the CME can flow along the Earth's magnetic field and collide with the atmosphere further south than usual, which sparks the northern lights in places they're not usually seen.

The more energetic and dense the CME, the stronger the geomagnetic storm, and the further south the northern lights are seen.

NOAA classifies geomagnetic storms on a scale of G1 (minor) to G5 (extreme), with G5 being the most powerful and least common. The G5 storm that was seen in May this year was the first of its kind since 2003, and resulted in aurorae being seen across all 50 U.S. states.

The upcoming CME was ejected from sunspot region 3901 at the same time as a powerful M9.4-class solar flare.

"A CME associated with a filament eruption occurred on 25/2024 near Region 3901 (S09W46, Hax/alpha). The filament eruption was modeled and is projected to hit Earth mid to late day on 28 Nov, the SWPC said in a forecast discussion.

"Filaments tend to be slower movers and can linger longer allowing it to disturb Earth's magnetic field longer. Therefore, a G1 Watch has been issued for the initial disturbance on 28 Nov with a G2 Watch for lingering enhancements into 29 Nov."

G1 storms can result in the northern lights being visible as far south as northern Michigan and Maine, while G2 storms may be visible from New York and Idaho.

How to see the Northern Lights well

Being further north gives you a better chance of spotting the northern lights in general, however, those further south hoping to catch a glimpse of the phenomena should seek dark skies with minimal light pollution or clouds.

"You need clear night skies," Huw Morgan, head of the solar physics group at the United Kingdom's Aberystwyth University, told Newsweek.

"Having a dark sky without light pollution is important. Taking a long exposure picture with your phone is an excellent way of recording the Northern Lights."

As well as the northern lights, geomagnetic storms can also induce electric currents in power lines, leading to transformer damage or large-scale blackouts, and may cause satellite damage or radio blackouts.

"The affected infrastructure that is of most importance is large-scale power grids, without which modern society would not be able to function," Brett Carter, an associate professor in space science at RMIT University in Australia, previously told Newsweek.

"Geomagnetically Induced Currents (GICs) are imposed on the power grids, and operators need to contend with them to make sure the equipment does not become overloaded; this is effectively what caused the widespread power outages across Quebec in the infamous 1989 storm.

"However, research over recent decades has significantly improved the resilience of power grids in key areas."

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