A surprise aurora lit much of the U.S. overnight Nov. 11–12 after a strong solar flare and coronal mass ejection. Another CME is headed toward Earth and could produce auroras again on the night of Nov. 12, but forecasts are uncertain because CMEs can change en route and small speed errors shift arrival by hours. Officials say the Veterans Day flare ranked among the larger events of Solar Cycle 25, and a rare G4 "severe" geomagnetic watch was issued — raising concerns about power, satellite and navigation impacts.
Will the Northern Lights Return Tonight? Why the aurora forecast is so uncertain
A surprise aurora lit much of the U.S. overnight Nov. 11–12 after a strong solar flare and coronal mass ejection. Another CME is headed toward Earth and could produce auroras again on the night of Nov. 12, but forecasts are uncertain because CMEs can change en route and small speed errors shift arrival by hours. Officials say the Veterans Day flare ranked among the larger events of Solar Cycle 25, and a rare G4 "severe" geomagnetic watch was issued — raising concerns about power, satellite and navigation impacts.
10:57 PM, 11/12/2025Science
Will the Northern Lights Return Tonight? Why the aurora forecast is so uncertain
A spectacular aurora display surprised much of the United States overnight on Nov. 11–12, and forecasters say it remains unclear whether a repeat will occur. Another strong coronal mass ejection (CME) is en route to Earth, so auroras could appear again on the night of Nov. 12 if conditions align.
Predicting the aurora is notoriously difficult. Unlike terrestrial weather forecasting, space-weather forecasters must follow activity on the sun roughly 93 million miles away, and CMEs frequently change strength and trajectory as they travel toward Earth.
“There are so many uncertainties, it makes it difficult to predict,” said Bill Murtagh, program coordinator at the Space Weather Prediction Center. He added that space-weather forecasting still lags terrestrial meteorology by decades.
Small errors in the predicted solar wind speed matter: if the forecasted speed is off by just 1%–2%, the CME’s arrival time can shift by about 1–2 hours — a large difference when visibility depends on whether the storm coincides with local night.
Space Weather Prediction Center service coordinator Shawn Dahl told AccuWeather that the Veterans Day solar flare was among the strongest so far in Solar Cycle 25. The sun moves through roughly 11-year cycles; as of late 2025 the sun is near the peak of Solar Cycle 25, when solar activity is highest.
On Nov. 11 the Space Weather Prediction Center issued a rare G4 “severe” geomagnetic storm watch, warning that the event could not only produce widespread auroras but also impact power systems, spacecraft operations, and satellite and radio navigation. According to DTN Weather, only four G4 watches had been issued during the current 11-year cycle (which began in December 2019) as of November 2025. The geomagnetic scale runs from G1 (minor) to G5 (extreme).
What to watch
- Timing: Arrival could shift by 1–2 hours from current forecasts — whether the lights are visible depends on whether the disturbance lasts into local night.
- Location: If a strong geomagnetic storm arrives after dark, auroras could be visible as far south as Alabama and northern California; the northern tier of the U.S. is most likely under the current outlook.
- Impacts: A G4 storm can affect power grids, satellites, GPS accuracy and radio communications — follow official advisories if you work with sensitive systems.
- Viewing tips: Seek a dark-sky location away from city lights, check updated space-weather alerts, and be prepared for short notice.
This story has been updated with new information. Originally published by USA TODAY: "Northern lights forecast for Wednesday in flux. Here's what to know."