Multiple solar events, including a series of coronal mass ejections (CMEs) and a high-speed solar wind stream, are forecast to impact Earth in early June 2026. Forecasters predict geomagnetic storms ranging from minor (G1) to severe (G4) levels, potentially making the aurora borealis visible across northern U.S. states.
Event Overview and Timeline
June 3-4, 2026
On June 3, a series of X-class solar flares were observed, followed by the launch of two to three Earth-directed CMEs, expected to reach Earth on June 5, according to Spaceweather.com.
On June 4, NOAA forecast a rapid escalation from quiet to active geomagnetic conditions, reaching G2 (Moderate) to G3 (Strong) levels mid-to-late in the day, with a chance of isolated G4 (Severe) conditions at night.
The U.K. Met Office advised that geomagnetic activity is expected to increase sharply on June 4, with G1–G3 conditions likely and a slight chance of isolated G4 intervals.
June 5, 2026
Forecasters anticipate the arrival of CMEs from the June 3 flares, which could combine with earlier disturbances. A G3 (Strong) to G4 (Severe) geomagnetic storm is possible, which could push the aurora viewing line further south into the United States.
Key Causes
Multiple solar events are being monitored as sources of the forecast geomagnetic activity:
- Coronal Mass Ejections (CMEs): Two to three CMEs were launched from the sun following X-class solar flares on June 3. Additionally, a CME launched on May 30 is also expected to contribute to the disturbance. Multiple CMEs traveling in close succession can interact and intensify, a phenomenon sometimes called a "cannibal CME."
- Co-rotating Interaction Region (CIR): A region where fast solar wind compresses slower material is expected to arrive.
- High-Speed Solar Wind Stream: A stream from a coronal hole is adding to the disturbance.
Aurora Visibility Forecast
U.S. States with Potential Visibility
NOAA and other forecasters have identified states with the highest potential for aurora visibility. Under G3 storm conditions, the northern lights may push into the northern U.S. If G4 conditions develop, visibility may extend to mid-latitudes.
- Best Prospects (States fully or partially within viewline): Washington, Idaho, Montana, Wyoming, North Dakota, South Dakota, Minnesota, Wisconsin, Michigan, New York, and Maine.
- Additional Potential States: Oregon, Nebraska, Iowa, Illinois, Indiana, Ohio, Pennsylvania, Massachusetts, Connecticut, Rhode Island, Vermont, New Hampshire, and possibly Colorado and Missouri.
- Specific Forecast for Utah: Under a G3 watch, the aurora may be visible in northern Utah and potentially across the rest of the state, according to a map from the Space Weather Prediction Center.
International Visibility
Auroras may also be visible over parts of Canada and northern Europe, including the U.K., subject to local cloud cover.
Observing Conditions and Challenges
- Best Viewing Time: The recommended viewing window is between 10 p.m. and 4 a.m. local time. The peak geomagnetic activity on June 4 is forecast for the afternoon and evening in North America.
- Lunar Interference: An 82%-lit waning gibbous moon will rise after midnight, potentially interfering with the visibility of faint aurora.
- Seasonal Limitations: In the lead-up to the June solstice, short nights and twilight may limit darkness, making aurora harder to see even under favorable geomagnetic conditions.
- Viewing Recommendations: Observers are advised to seek dark locations away from light pollution with an unobstructed view of the northern horizon. Smartphone cameras in night mode may detect faint auroral glows not visible to the naked eye.
Forecast Limitations and Key Indicators
Space weather forecasts can change rapidly. Accurate prediction of CME arrival and impact is limited, with NOAA's DSCOVR satellite providing only approximately 30 minutes of warning after the CME arrives at its position.
The crucial factor for aurora intensity is the orientation of the interplanetary magnetic field's north-south component (Bz). A sustained southward Bz of -5 nT or stronger typically signals imminent aurora.
Causes and Scientific Background
A CME is a cloud of superheated gas and magnetic fields ejected from the sun. When these clouds interact with Earth's magnetic field, they can trigger geomagnetic storms. These storms are classified on a scale from G1 (minor) to G5 (extreme).
The aurora borealis is an atmospheric phenomenon that occurs when charged particles from the sun interact with Earth's magnetic field lines near the poles, colliding with nitrogen and oxygen molecules and causing them to release energy as light.
The current period of heightened auroral activity aligns with the solar maximum, the peak of the sun's 11-year cycle, which produces increased solar flares and CMEs. Forecasters expect conditions for auroral displays to begin to lessen after 2026.