Northern Lights Sightings

In the early hours of June 1st and 2nd of 2025, the Northern lights, otherwise known as the aurora borealis were visible in Northern California. This is for the second year in a row, having been visible last in May of 2024. Why is this? Where were they seen? When will they be seen next?

The aurora borealis are caused by several factors coming together, in this instance there was a massive geomagnetic storm that was triggered from a coronal mass ejection (CME) from the sun. This specific CME originated from sunspot AR4100, which promptly reached Earth on June 1st, 2025. This caused a G-4 class geomagnetic storm, the second strongest level on a five point scale. G-4 class storms are capable of affecting plenty of things, such as electronics, satellites and power grids. On a positive note, it creates the perfect conditions for the aurora borealis.

The situation has been monitored closely by astronomers and space weather experts, these individuals are providing information on how to view the Northern lights and alerts on when. Experts like Gerald McKeegan, an astronomer at Chabot Space and Science Center, advised residents to find dark, elevated locations away from city lights for optimal viewing. According to an article by SFGATE, “This aurora borealis is special however, as the States as south as Alabama were able to witness them.”

When will they be seen next? This is a very open ended question, however as we approach the Solar Maximum in July of 2025, next month, solar activity will increase. With the increase of solar activity it is expected to see an increase of geomagnetic storms, causing more auroral displays. Unfortunately, with the dates for these most recent sightings having passed, opportunities to witness the Northern lights in California should come again in the next few months. The chances of being able to view these phenomena increase as you stay informed through space weather forecasts and being prepared to venture into dark, rural areas to increase the chance of viewing the Northern lights.

Image Courtsey: Rémi Lanvin