A severe solar storm struck Earth Tuesday, creating vivid views of auroras—often referred to as the Northern Lights— and potentially affecting power grids and GPS tracking.
The storm intensified around 10 a.m. ET Tuesday to G4 status, just one notch below the highest level solar storm, according to the NOAA's Space Weather Prediction Center.
The geomagnetic storm is the strongest so far of the current solar cycle, which happens every 11 years or so, according to Spaceweather.com. It's expected to carry on into the evening.
The event happened in response to a pair of coronal mass ejections that were observed leaving the sun on Sunday.
CMEs, which are basically bursts of gas and magnetic field emitted from the sun, can impact power systems, radio transmissions and GPS signals when they interact with the Earth's atmosphere, according to NOAA. However, it said it hadn't received reports of impacts as of yet.
Before sunrise, bright auroras were sighted over several northern-tier U.S. states, including Minnesota, Wisconsin, Montana, the Dakotas and Washington, according to Spaceweather.com.
Space Weather branch chief Brent Gordon told The Associated Press that if the storm effects continued through Tuesday evening, there was a "very strong possibility" that the northern lights could be seen as far south as the middle United States, even Tennessee and Oklahoma. That also means much of Russia and northern Europe, as far south as central Germany and Poland, had the potential for the sky show.
The current solar cycle is also expected to bring a total solar eclipse Friday, the first of its kind in 16 years. The event is expected to be a serious challenge for Europe, which has the world's largest interconnected grid.
As much as 35,000 mega watts of solar energy—the equivalent of nearly 80 medium size conventional power plants—will be pulled from Europe's electrical system, according to the European Network of Transmission System Operators. It has the potential to knock out photovoltaic power production.
The Associated Press contributed to this report.