The northern lights could dip into nine US states tonight

Skywatchers across a swath of the northern United States have a chance to see the aurora borealis without leaving the country, after forecasters flagged a geomagnetic disturbance strong enough to push the light show unusually far south. Space weather forecasters say the display could become visible in as many as nine states, stretching well beyond the far-northern latitudes where the aurora is normally confined. The exact reach of any given storm is notoriously hard to pin down in advance, but the forecast has been enough to send aurora chasers scrambling to plan a clear-sky viewing spot for tonight.

A Geomagnetic Storm Pushes the Aurora South

Per forecast coverage circulating ahead of the event, the aurora could reach as far south as nine US states tonight, a noticeably wider reach than the handful of northern-tier states that typically get a shot at seeing it. A geomagnetic storm forms when a burst of charged particles from the sun slams into Earth’s magnetic field, energizing it and funneling extra particles down toward the poles, where they collide with atoms in the upper atmosphere and release the glowing greens, reds, and purples associated with the aurora. The stronger the storm, the farther from the poles that glow becomes visible, which is why an unusually active night can put the aurora within reach of viewers far south of its normal range.

What’s Driving Tonight’s Solar Storm

Aurora displays reaching into the mid-latitudes are almost always tied to activity on the sun, whether a coronal mass ejection hurling a cloud of plasma toward Earth or a high-speed stream of solar wind flowing from a gap in the sun’s outer atmosphere. Both types of events can compress and disturb Earth’s magnetic field once they arrive, and the resulting geomagnetic storm is typically rated on a scale that runs from minor to extreme based on how strongly it disturbs the field. A storm strong enough to push visibility into nine states suggests a moderate-to-strong disturbance, the kind that shows up a few times a year rather than something that happens on a nightly basis.

Space weather agencies typically rank geomagnetic storms on a graduated scale running from minor disturbances up through extreme events, with each step up the scale corresponding to a wider band of latitudes where the aurora might become visible and a greater risk of side effects like radio interference or fluctuations in satellite and power-grid systems. A minor storm might only nudge the aurora slightly beyond its usual range near the poles, while a severe or extreme storm can, in rare cases, push visibility deep into the middle latitudes of a country the size of the United States. Forecasters watch incoming measurements of the solar wind’s speed, density, and magnetic orientation in the hours before a storm arrives, since a stronger and more southward-pointing magnetic field in the incoming plasma tends to couple more efficiently with Earth’s own field and produce a more intense display.

Why the Aurora Glows in Different Colors

The aurora’s color depends on which atmospheric gas is being struck by incoming charged particles and at what altitude the collision happens. Oxygen atoms produce the familiar green glow that dominates most displays when struck at lower altitudes, while oxygen higher in the atmosphere can produce a rarer red hue. Nitrogen molecules, meanwhile, tend to contribute blue and purple tones, often appearing along the lower fringes of a display. A particularly energetic storm can drive particles deep enough into the atmosphere, and across a wide enough range of altitudes, to produce a fuller mix of these colors in a single night’s display rather than the more typical green-dominated glow, which is part of why unusually strong storms tend to produce the vivid, multicolored photos that circulate widely afterward.

Where the Northern Lights Might Be Visible

When a storm like this hits, the odds of a clear view are generally best across the northern tier of the country, from the Pacific Northwest through the Upper Midwest and into New England, along with parts of the Mountain West at higher elevations and darker skies. Visibility on any given night still depends heavily on local weather, cloud cover, and how far a viewer is from city light pollution, so even within states officially included in a forecast, some observers will have a far better shot than others simply based on where they are standing and what the sky looks like above them.

Tips for Catching a Glimpse

Aurora hunters generally have the best luck heading away from urban light domes to a spot with an unobstructed view of the northern horizon, since the display often appears low in the sky rather than directly overhead unless the storm is unusually intense. Modern smartphone cameras, with their longer exposure times, frequently pick up faint auroral color that is barely perceptible to the naked eye, so taking a quick photo of the northern sky can help confirm whether a subtle glow is actually the aurora before writing off a clear night as a bust. Patience matters too, since geomagnetic activity can ebb and flow over the course of a single night.

How NOAA Tracks and Forecasts Aurora Activity

The federal government’s primary hub for this kind of forecasting is the Space Weather Prediction Center, which monitors solar activity around the clock and issues alerts when a coronal mass ejection or high-speed solar wind stream is likely to reach Earth. Forecasters there track incoming space weather using a network of satellites positioned between the sun and Earth, giving them roughly a day or more of advance warning before a disturbance arrives, though the precise strength and timing of the resulting aurora display often remains uncertain until the event is already underway.

This article was produced with the assistance of AI and reviewed by Morning Overview editors.

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