The northern lights may be visible overnight from up to 10 northern U.S. states on Saturday, April 25, into Sunday, April 26, according to a forecast by space weather experts at the National Oceanic and Atmospheric Administration.
It comes in the wake of double M1-class solar flares on the sun on April 23. In their wake, NASA’s orbiting Solar Dynamics Observatory tracked a coronal mass ejection (CME) — a cloud of super-charged particles — traveling in the direction of Earth. CMEs often cause aurora displays. According to Spaceweather.com, this one is expected to graze Earth’s magnetic field.
Northern Lights Tonight: Forecast
The forecast is for a G1 (minor) geomagnetic storm in the offing. “Isolated G1 (Minor) geomagnetic storming conditions are possible on April 26 in response to the arrival of the glancing CME impact,” said NOAA.
The northern lights are caused by the solar wind, a constant stream of charged particles flowing from the sun that interacts with Earth’s magnetic field. While most are deflected, some particles spiral along magnetic field lines toward the poles, colliding with oxygen and nitrogen atoms high in the atmosphere. These collisions excite the gases, causing them to release energy as shimmering light.
Northern Lights Forecast: Where And When
A G1-class geomagnetic storm could see aurora visible on the northern horizon from around 10 northern U.S. states and Canada on Saturday, April 25, into Sunday, April 26 — though timings are always subject to change.
U.S. states that may see aurora include States with the best chance include Alaska and (northerly parts of) Washington, Idaho, Montana, North Dakota, South Dakota, Minnesota, Wisconsin, Michigan and Maine.
If a G2-class geomagnetic storm erupts, aurora may be viewable from states farther south, such as Oregon, Wyoming, Nebraska, Iowa, Illinois, Indiana, Ohio, New York, Vermont and New Hampshire.
Since urban glow can make faint aurora hard to see, drive 30-60 minutes north from city centers or use a light pollution map to locate darker skies. Dark Sky Places and lakeshores north of cities often make excellent viewing spots. The rule is simple: the darker the northern sky, the more vibrant the display — even during moderate geomagnetic storms.
Northern Lights Forecast: Latest Updates
To check visibility in real time, use NOAA’s 30-minute aurora forecast or download apps such as Aurora Now, My Aurora Forecast or Glendale Aurora for up-to-the-minute alerts and live solar wind data.
Aurora-chasers frequently use the Kp index to predict the intensity of a geomagnetic storm, but for aurora displays, the interplanetary magnetic field’s Bz component is more important (you’ll find it in some of the above apps and on SpaceWeatherLive.com). Bz determines how easily solar energy enters Earth’s magnetosphere. When Bz points north, Earth’s field resists it; when Bz swings south, the two fields connect, allowing plasma to stream in. A sustained southward Bz of −5 nT or stronger usually signals an imminent display of aurora.
Northern Lights Forecast: How To Photograph Aurora
A mirrorless or DSLR camera is ideal (ISO 1600, 2-10 seconds, f2.8), though newer smartphones are increasingly capable of stunning results. If your smartphone has a Night Mode or Pro Mode, you can capture a beautiful aurora photo with these steps:
- Use your main lens, not the ultra-wide, for sharper results.
- Stabilize the camera using a tripod or rest it on a firm surface such as a car roof, wall, or post.
- Shoot in RAW format if available, as it makes post-editing easier.
- Expect long exposures between five and ten seconds. Even faint glows that look grayish to the eye often appear vividly green, purple or red in photos.
Wishing you clear skies and wide eyes.
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