For many Americans, this Christmas Eve could come with a bonus spectacle: shimmering curtains of green, red and purple northern lights stretching over parts of the night sky. A combination of fast solar wind and a recent coronal mass ejection (CME) from the sun is expected to disturb Earth’s magnetic field enough to trigger a minor geomagnetic storm, raising the odds of aurora sightings across several northern U.S. states on the night of December 24–25, 2025.

Image Illustration. Photo by Juho Luomala on Unsplash

What’s Driving the Christmas Eve Aurora Forecast

Forecasters at NOAA’s Space Weather Prediction Center (SWPC) expect active geomagnetic conditions and a G1-class geomagnetic storm—classified as “minor” on a five-step scale—around Christmas Eve, as Earth passes through high-speed solar wind emerging from a large “coronal hole” on the sun and feels the glancing effects of a CME that erupted on December 20. A G1 storm typically corresponds to a planetary Kp index of 5, an internationally used scale from 0 to 9 that measures disturbances in Earth’s magnetic field, with values of 5 or above signaling a geomagnetic storm. During such events, auroras often intensify and spread farther from the poles.

Recent forecasts highlight that space weather remains “unsettled” in the days leading up to Christmas, with solar wind speeds running roughly double their normal rate due to the coronal hole, a cooler, magnetically open region of the sun’s outer atmosphere that funnels charged particles into space at high speed. That fast wind, combined with any extra jolt from the December 20 CME, is what could set the stage for a festive light show.

Which U.S. States Could See the Northern Lights?

Based on NOAA’s experimental aurora “viewline” maps—which use models of expected geomagnetic activity between 6 p.m. and 6 a.m. Central Time to show where auroras are most likely—the Christmas Eve storm could push visible auroras into parts of roughly 10 northern U.S. states. Those odds are highest where the auroral oval—the ring of activity around the magnetic pole—normally brushes the continental United States.

According to analyses of NOAA’s forecast, skywatchers in the following states are likely to have the best chances if skies are clear:

• Alaska

• Washington

• Idaho

• Montana

• North Dakota

• South Dakota

• Minnesota

• Wisconsin

• Michigan

• Maine

These states lie closest to the forecast view line for a Kp of around 5 on December 24–25, when a G1 storm is most likely. In stronger-than-expected bursts—if the storm briefly intensifies or if the magnetic field aligns just right—fainter glows could even creep toward the northern horizons of states like northern New York, Vermont or New Hampshire, though those locations are on the edge of current predictions.

Why the Northern Lights Are Reaching Farther South

The Christmas Eve forecast doesn’t come out of nowhere. The sun is in a stormy phase of its roughly 11-year solar cycle, known as solar maximum, when sunspots, flares and CMEs become more frequent and powerful. Over the past year, several strong geomagnetic storms have pushed auroras into unusually low latitudes, with one November 2025 event lighting up skies from New York to Texas and California during a G4 (“severe”) storm.

Auroras are caused when charged particles from the sun stream along Earth’s magnetic field lines and collide with atoms of oxygen and nitrogen in the upper atmosphere, typically 60 to 250 miles above the surface. Those collisions energize the atoms, which then emit light as they return to their normal state. The precise colors depend on which atoms are involved and at what altitude—green often comes from oxygen around 60 to 150 miles up, while red auroras often form higher, and purples and blues can arise from nitrogen.

Understanding the Kp Index and G-Scale

For anyone trying to decode aurora alerts, two numbers matter most: the Kp index and the NOAA “G-scale.” Kp runs from 0 (quiet) to 9 (extreme storm). NOAA categorizes storms from G1 (minor) at Kp 5 up to G5 (extreme) at Kp 9. As Kp rises, the auroral oval expands toward the equator. Around Kp 6–7, auroras can reach the northern edges of the contiguous United States; during rare Kp 8–9 blowouts, they may be visible as far south as the central U.S.

NOAA notes that even at more modest Kp levels of 3 to 5, observers under dark skies in the right locations can see dynamic, photogenic auroras if they are directly beneath the auroral oval or just poleward of it. That’s why northern-tier states are so well positioned for Christmas Eve: they sit close to the typical edge of the oval during a G1 storm, increasing the odds of at least a faint glow.

How to Give Yourself the Best Chance to See the Lights

Even with favorable forecasts, seeing the northern lights is never guaranteed. The aurora can flare up and fade quickly, and local conditions on the ground can make or break visibility. NOAA recommends four main ingredients: strong geomagnetic activity, clear skies, darkness and patience.

• Check short-term space weather maps: NOAA’s 30-minute aurora forecast uses real-time solar wind data to estimate auroral intensity and location up to about 90 minutes ahead.

• Get away from city lights: Light pollution can easily wash out faint auroras, especially near the horizon. Rural locations with dark northern horizons improve the odds dramatically.

• Watch the northern sky between 10 p.m. and 2 a.m.: Statistically, auroras are most active around local midnight, though displays can appear earlier or later during strong storms.

• Use your camera: Modern smartphones in night or long-exposure modes can capture subtle auroral color and structure that the naked eye may only perceive as pale gray or milky arcs.

A Holiday Treat With a Technological Edge

Behind the beauty of the aurora lies serious space weather. Even minor geomagnetic storms like the G1-level event forecast for Christmas Eve can disturb radio signals, satellite operations and power grids, though significant impacts are rare at this level. More intense storms, such as those reaching G3 or G4 on NOAA’s scale, can cause intermittent high-frequency radio blackouts, degrade GPS accuracy and induce currents in long power lines.

This year, as the sun continues its active peak, space weather experts expect more chances for mid-latitude auroras in the months ahead. For now, Christmas Eve offers a timely reminder that the same solar storms that gently paint the sky with color can, under the right circumstances, ripple through the technologies that power modern life.

If the Forecast Holds, Look Up

Forecasts can and do change quickly in space weather, and even accurate models cannot guarantee that any given town or city will witness the aurora on Christmas Eve. Cloud cover, local light pollution and the timing of geomagnetic disturbances all play a role. But for residents of Alaska and the northern tier of the continental United States, the odds this year are better than usual that Christmas lights might extend far beyond the front yard and into the high atmosphere itself.