The Northern Lights may be seen in northern U.S. states and along the U.S.-the Canada border this weekend after space weather forecasters predicted favorable geomagnetic storm conditions.
The National Oceanic and Atmospheric Administration’s Space Weather Prediction Center’s forecast has a G1-rated geomagnetic storm likely commencing overnight on Saturday, May 17 through Sunday, May 18.
It comes in the wake of the biggest solar flare in 2025 so far, and just over a year after an extreme G5 geomagnetic storm on May 10-11, 2024. That was the strongest for 20 years and perhaps for hundreds of years.
Those under clear, dark skies away from light pollution may see the glow of the aurora borealis low on the northern horizon from northern U.S. states, with a waning gibbous moon rising well after midnight making conditions ideal.
Aurora Alert: Where To See The Northern Lights
A G1 geomagnetic storm is forecast to begin around 09:00 UTC on Sunday, May 18. That translates to 5:00 a.m. EDT, 4:00 a.m. CDT, 3:00 a.m. MDT and 2:00 a.m. PDT. However, forecasts are very fluid, both in terms of timings and intensity. It could, in practice, turn out to begin sooner or later, and be either a weaker display or a stronger G2 geomagnetic storm.
During G1 storms, aurora is commonly visible at high latitudes — such as northern Michigan and Maine — according to NOAA. G2 storms are generally seen as far south as New York and Idaho.
U.S. states where aurora could be glimpsed in the north include Alaska, northeastern Washington, northern Idaho, Montana, North Dakota, northern South Dakota, Minnesota, northern Michigan, Wisconsin and northern Maine.
Aurora is typically seen in polar regions at around latitudes of 70 degrees north and south, but during strong geomagnetic conditions the auroral oval can bulge, with displays then seen as far as 40 degrees north and south. Solar activity is currently at a 23-year high, though slightly on the wane since the solar maximum in late-2024.
Aurora Alert: How Strong The Northern Lights Will Be
The predicted displays of aurora borealis have a predicted Kp index of 4.67. The Kp index is an imperfect measure of how far from the poles the aurora oval reaches. According to NOAA, during a Kp 3-5 display, “the aurora will move further from the poles, it will become brighter, and there will be more auroral activity (motion and formations). If you are in the right place, these aurora can be quite pleasing to look at.”
Space weather is unpredictable and the forecast can change quickly. Skywatchers are advised to check NOAA’s Aurora view line, which is available for tonight and tomorrow night, as well as its 30-minute forecast and X account, where the latest forecasts are posted.
The Northern Lights are caused by the solar wind, a stream of charged particles from the sun that interacts with Earth’s magnetic field. As charged particles strike Earth’s magnetic field, they accelerate down its magnetic field lines at the north and south poles, exciting particles in the atmosphere to create ovals of green and red.
Aurora Alert: Recent Solar Flares
X1.2 and X2.7 solar flares — intense bursts of energy and electromagnetic radiation — were ejected by the sun on May 13 and May 14. X-class denotes the most intense flares, while the number provides more information about its strength, according to NASA. They were the strongest since March 28, and of 2025 so far. Two slightly weaker M-class solar flares, rated M5.3 and M4.7, followed on May 14.
Wishing you clear skies and wide eyes.
