A powerful G4 geomagnetic storm is bearing down on Earth, promising a rare mix of technological risk and spectacular skies for people far from the polar regions. As the storm intensifies, power grid operators, satellite controllers and aviation networks are on alert, even as skywatchers prepare for a potential curtain of color stretching across much of the continent.
I see this storm as part of a broader pattern of increasingly intense solar activity that is reshaping how we think about space weather, from the resilience of our infrastructure to the way ordinary people track the northern and southern lights. The same forces that can disturb navigation and communications are also poised to turn the night sky into a temporary gallery of shimmering aurora.
What a G4 solar storm actually means
On the five-step scale that space weather forecasters use, a G4 event sits just below the most extreme category, signaling a severe geomagnetic storm with the potential to disturb key technologies and ignite auroras far from the poles. The classification reflects how strongly the solar wind and its embedded magnetic field are buffeting Earth’s own magnetic shield, a process tracked in real time by the space weather center that issues alerts to utilities, airlines and emergency managers.
At this level, the storm is strong enough that federal agencies treat it as a potential hazard, not just a curiosity in the sky. Earlier coverage of G4 conditions has noted that at these intensities, FEMA is notified so it can prepare for possible communication interruptions, and forecasters at the same national center coordinate with grid operators and other critical sectors. That institutional response underscores that a G4 is not routine background noise from the Sun, but a space weather event with real-world stakes.
How this storm could hit power, satellites and communications
The main concern with a severe geomagnetic storm is not a Hollywood-style blackout, but a series of cascading stresses on systems that quietly underpin daily life. When charged particles from the Sun interact with Earth’s magnetic field, they induce currents in long conductors such as high-voltage transmission lines, pipelines and undersea cables, which can overload equipment or force operators to take protective actions. Earlier G4 and G5 events have shown that Storm Consequences can include high-voltage lines tripping on the ground while satellites experience anomalies in orbit.
Radio and navigation systems are also vulnerable, particularly those that rely on the ionosphere, the electrically charged layer of the upper atmosphere that a storm can disturb. Past events have produced Effects such as degraded high-frequency radio, loss-of-lock for GPS receivers and disruptions to aviation communications on polar routes. Risk analysts warn that a G4 storm can create widespread disruption to radio and electrical systems, particularly when it is driven by a fast coronal mass ejection that has produced a halo signature around the Sun, a pattern highlighted in assessments of why a Oct G4-class event drew so much attention from insurers and infrastructure planners.
Lessons from the biggest storms in decades
To understand what this new G4 could do, I look back at the cluster of powerful storms that hit earlier in the current solar cycle, which offered a kind of dress rehearsal. The solar storms of May 2024 were a series of intense events, with extreme solar flares and geomagnetic disturbances that produced auroras across wide swaths of the Northern and Southern Hemispheres, as documented in reconstructions of the solar storms of May. Those storms were strong enough that scientists described them as among the most significant in the past 20 years, and they provided a wealth of data on how modern infrastructure responds.
Space agencies have since detailed how they tracked and analyzed that sequence, noting that Mara Johnson and colleagues described May 2024 as a particularly stormy month for the Sun, with activity rivaling some of the most intense storms in the past 500 years. Another analysis of What Happened During the Biggest Geomagnetic Storm in Over 20 Years explains that On May 10, 2024, the first G5 or “severe” geomagnetic storm of this cycle struck, prompting scientists to study how best to weather similar events in the future. Those case studies now inform how operators are preparing for the current G4, from adjusting satellite orientations to reconfiguring grid loads.
Real-world damage: from farms to grids
One of the most sobering lessons from recent storms is that the damage is not theoretical. During the May 2024 sequence, researchers found that the storm negatively affected ground-based systems in ways that translated directly into financial losses. In one documented case, Affected farms lost an estimated $17,000 each when automated equipment malfunctioned as a result of the storm’s effects, a figure that underscores how even rural operations far from big cities can feel the impact of space weather.
Those findings came from work by University of Victoria researchers, who traced how geomagnetically induced currents and communication glitches cascaded into real-world disruptions. Their analysis dovetails with broader warnings that a G4 magnetic storm has a high impact force that can affect communications, power grids, navigation systems, satellite flight, oil and gas pipelines, long-distance telephone lines and even human health, as summarized in regional advisories that describe how A G4 magnetic storm can influence everything from drilling operations to medical devices. Taken together, these examples show that the stakes of the current storm extend well beyond the power grid alone.
Why the aurora will reach so far from the poles
For all the concern about infrastructure, a severe geomagnetic storm is also a rare gift for skywatchers, because it pushes the auroral oval far toward the equator. During the May 2024 storms, auroras were visible in many places at unusually low latitudes, with maps showing the typical midnight equatorward boundary of aurorae at different Kp levels and documenting sightings as far south as 24°S MLAT, a pattern captured in the Auroras section of that event’s record. Those displays demonstrated how a strong storm can transform the night sky for people who have never seen the northern or southern lights before.
Forecasts for the current G4 suggest a similar expansion, with models indicating that the Northern Lights, also called aurora borealis, could be visible across a broad swath of the United States if the storm’s magnetic field lines up favorably with Earth’s. A recent outlook noted that a geomagnetic storm of this strength could make the Northern lights visible for several nights in a row for states well south of their usual viewing zone, while another forecast highlighted that a severe geomagnetic storm could make the aurora visible as far south as New York City and Chicago in a detailed Northern lights forecast. For those in the Southern Hemisphere, images of Aurora Australis in Antarctica captured during a period of heightened solar activity in May 2024 show how the ongoing solar cycle is already boosting the aurorae visible here in both intensity and frequency.
Tracking the lights: where and when to look
For anyone hoping to see the sky light up, timing and location matter as much as the storm’s raw strength. The best views typically come around local midnight, when the auroral oval is centered on the night side of Earth and the sky is darkest, but strong storms can produce visible structures for hours on either side of that peak. To narrow down the odds, I rely on regional tools such as the aurora forecast that provides short-term predictions of activity over Alaska and surrounding regions, translating complex space weather data into simple maps that show where the lights are most likely to appear.
National forecasts complement those regional tools by translating geomagnetic indices into plain-language guidance about where the aurora might be visible on the ground. One recent advisory explained that a strong storm could make the Northern Lights visible across North America and as far south as Mexico, with photos showing curtains of color stretching over cities and rural landscapes alike during a Severe geomagnetic storm that lasted well into the night. Another forecast tied to a G4 watch noted that the category G4 watch from the national space weather center meant the aurora could reach as far south as California, with California specifically highlighted as a place where residents might glimpse the glow if skies cleared.
Why this storm fits a more active solar cycle
The current G4 storm is not an isolated outburst, but part of a broader ramp-up in solar activity as the Sun approaches the peak of its roughly 11-year cycle. Scientists tracking the cycle have already revised their expectations, noting that solar activity is now expected to peak earlier and to be stronger than previously thought, a shift that was underscored when a recent geomagnetic storm turned out to be the strongest since 2005. In that context, analysts have emphasized that while this geomagnetic storm is unlikely to cause catastrophic failures, it is a reminder that Solar activity can stress systems in ways that demand careful preparation, even if most people will be mostly protected.
Some of the most dramatic recent storms have been driven by enormous sunspots and rapid-fire eruptions, a pattern that appears to be repeating now. Earlier in the cycle, forecasters warned that a sunspot seven times the size of Earth was sending a series of coronal mass ejections toward our planet, explaining that Since these oncoming coronal mass ejections had a relatively strong magnetic field, Friday’s auroras were forecast to make the lights visible across a wide range of US states, according to an analysis that traced the threat back to a region of the Sun described by Since and Friday. Another report chronicled how the Sun released another powerful burst of energy that triggered a secondary peak in an Extreme geomagnetic storm, noting that The Sun continued to fire off eruptions through the afternoon of May 13, 2024. That pattern of repeated hits is exactly what forecasters are watching for as the current G4 unfolds.
How officials and operators are preparing
Behind the scenes, a severe geomagnetic storm triggers a well-rehearsed choreography among agencies and private operators. When forecasters issue a G4 watch, grid managers begin adjusting power flows, scheduling extra staff and reviewing contingency plans so they can respond quickly if transformers or transmission lines show signs of stress. One widely cited briefing on the strongest solar storm since 2005 explained that at the strong G4 level, impacts on our infrastructure are possible, but that advance warning allows operators to prepare and respond quickly, a point captured in the section titled How will the solar storm impact Earth’s infrastructure. That same analysis stressed that Earth is not defenseless, because modern grids are designed with some margin for geomagnetic disturbances.
Emergency managers and aviation authorities are also part of the response. A recent overview of a severe geomagnetic storm that hit Earth noted that a severe geomagnetic storm that hit Earth had the potential to knock out power and electronics, but also emphasized that advance alerts give operators time to take protective action, a point highlighted in a detailed explanation of how a G4 watch for Earth allows utilities and satellite controllers to adjust. In practice, that can mean rerouting polar airline flights to lower latitudes to avoid radio blackouts, putting some satellites into safe mode to reduce the risk of damage and coordinating with pipeline operators who monitor induced currents along long stretches of buried infrastructure.
Balancing risk and wonder in the night sky
For all the technical complexity, a G4 storm is also a profoundly human event, because it invites people to look up and see Earth’s magnetic shield in action. During a recent severe storm, photographers captured vivid curtains of color across North America and as far south as Mexico, with images showing how the aurora danced over city skylines and rural fields alike in a North America and Mexico display that lasted well into the night. Those scenes are likely to be repeated if the current storm’s magnetic field tilts southward, opening a channel for energy to pour into the upper atmosphere.
At the same time, there is evidence that our systems are becoming more resilient, even as storms grow stronger. Commentators tracking the latest G4 event have noted that, Fortunately, as of November 12th, 2025 no serious disruptions to the utility grid have been reported from the G4 that’s lighting up the skies, a reassuring line from an analysis that framed the storm as both a risk and a spectacle, captured in the observation that Fortunately the grid has held up. Video explainers have echoed that dual message, with one widely shared clip describing how the most powerful solar storm of the year has just struck our planet, igniting skies with dazzling auroras while also walking viewers through why the most powerful solar storm of the year is not expected to cause catastrophic failures. For now, the challenge is to keep strengthening the systems we rely on, even as we step outside to enjoy the rare light show that a severe solar storm can bring.
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