On Friday and Saturday nights, viewers from San Francisco to Tasmania were treated to amazing auroras in the night sky. One of the biggest geomagnetic storms in decades may continue tonight and even through the week, according to the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center.

«At least five Earth-directed coronal mass ejections were observed and expected to arrive as early as midday Friday, May 10, 2024, and persist through Sunday, May 12, 2024,» the center noted. «Several strong flares have been observed over the past few days and were associated with a large and magnetically complex sunspot cluster, which is 16 times the diameter of Earth.»

In most cases, geomagnetic storms cause little to no disruption on Earth, with radio communications and satellites affected most often. In extreme cases, a geomagnetic storm can cause significant and potentially life-threatening power outages, as well as problems with satellite systems and radio communications.

«Geomagnetic storms can impact infrastructure in near-Earth orbit and on Earth’s surface, potentially disrupting communications, the electric power grid, navigation, radio and satellite operations,» NOAA said, adding that representatives of the center have notified the operators of these systems so they can take protective action. 

The Washington Post notes that «anyone using high-frequency radio in the aurora viewing zone may experience some disruptions,» but also reports that most people will not be affected or need to take any special precautions beyond those they’d take with any storm that could knock out power.

Since consumer wireless networks use different radio frequencies, CNN notes that your phone is unlikely to be affected. Severe geomagnetic storms could affect the power grid, but wireless carriers generally have backups and can deploy mobile cellular towers.

In most cases, geomagnetic storms also present unique opportunities to see auroras in the night sky. When the storms hit, the plasma they carry creates a jaw-dropping aurora, illuminating the night sky with brilliant colors. Those auroras can be especially pronounced during the most intense phases of the storm, making for nice stargazing.

Where can you see these aurora borealis light shows?

«Geomagnetic storms can also trigger spectacular displays of aurora on Earth,» the NOAA said. «A severe geomagnetic storm includes the potential for aurora to be seen as far south as Alabama and Northern California.»

NOAA has created some (experimental) viewlines for watching the auroras, as well as a 30-minute aurora forecast that shows the last 24 hours of activity.

Does it seem like you can never see a hyped aurora where you live? Bill Murtagh, program coordinator at NOAA’s Space Weather Prediction Center, talked to CNET about this very issue back in 2022. Murtagh compared it to a popular outdoor hobby that also takes a lot of patience — fishing.

«You might be out hunting it for hours on end,» he told me, «and then, the perfect storm of events comes along, and you finally see it.»

He also noted that city dwellers are at a disadvantage due to light pollution, which is pretty much exactly what it sounds like, the brightening of the night sky in the city, caused by streetlights and other sources. That inhibits our ability to see stars and planets.

But say you get in the car and drive out of your city or suburb to a rural area with no streetlights. There’s another element that’s out of your control — the weather. Cloudy conditions can roll over any state at any time, making aurora sightings even tougher to predict.

Many people travel to Alaska or northern countries just in the hope of seeing, and photographing, an aurora. Murtagh recommended Anchorage, Fairbanks, Yukon, Helsinki and northern Scandinavia. There are even trip planners now who organize tours around hoping to see the aurora.