6 days ago
- Climate
- San Francisco Chronicle
Northern lights may be visible Sunday night over California. Here's the best way to see them
The northern lights were visible across unusually low latitudes of the U.S. on Saturday night and could even make an appearance across portions of California on Sunday night.
Residents in Seattle were treated to a dazzling display of purple and green hues early Sunday morning. Webcams across Northern California picked up northern lights, scientifically known as the aurora borealis, on the horizon. The enhanced auroral activity is being caused by a 'severe' geomagnetic storm, a level 4 out of 5 on the Space Weather Prediction Center's scale.
A G4 or greater geomagnetic storm watch remains in effect Sunday into Monday morning. At this intensity, the northern lights could again be visible in portions of Northern California, especially from long-exposure cameras.
Skies are expected to be mainly clear across Northern California on Sunday night, but there will be a few scattered high clouds to contend with. Some patchy fog along the coast could also spoil visibility of the aurora.
Areas away from city light pollution will provide the best viewing chances for the northern lights. A waxing crescent moon could also make the aurora more difficult to see with the naked eye.
The ongoing solar storm is caused by coronal mass ejections, pulses of the sun's magnetic field lurching toward Earth.
G4 watch remains in effect for tonight, June 1 (EDT), as CME passage continues. CME passage is slowly weakening, but conditions still elevated, therefore additional periods of G3-G4 remain possible, although less likely. Continue to visit for latest info
— NOAA Space Weather Prediction Center (@NWSSWPC) June 1, 2025
'The G4 (Severe) geomagnetic storm watch remains in effect for tonight, June 1, as CME passage continues,' the Space Weather Prediction Center wrote. 'There are indications that the coronal mass ejection (CME) passage is weakening, but the solar wind conditions remain elevated, therefore additional periods of G3-G4 (Strong-Severe) levels remain possible.'
According to the Space Weather Prediction Center, as 'CMEs leave the sun, it is possible to predict their path to determine if they will impact Earth. This technique is more challenging and the accuracy of these medium-range forecasts is not as good.' However, the aurora can be predicted 'quite accurately' 15 to 45 minutes in advance by measuring other astronomical conditions, such as the solar wind and interplanetary magnetic field upstream of Earth.
Strong coronal mass ejections can disrupt radio and satellite transmissions, potentially cause power outages and interfere with other pieces of infrastructure.
Solar activity, which rises and falls on an 11-year cycle, is peaking. In May 2024, an extreme geomagnetic storm resulted in northern lights sightings all across California, even for some city dwellers. In October 2024, a severe geomagnetic storm brought another display to portions of the state, although less widespread than the May event.
An average of 100 severe geomagnetic storms are classified as severe or greater in a typical 11-year solar cycle, according to the Space Weather Prediction Center.
