The northern lights were visible in the Pittsburgh area. Here's a look at the spectacular photos.
The northern lights were on display in the Pittsburgh area on Tuesday night.
The aurora borealis — the phenomenon more commonly known as the northern lights — was spotted all across southwestern Pennsylvania, including in Butler, Indiana, Westmoreland, Washington and Venango counties.
Scientists at the National Oceanic and Atmospheric Administration's Space Weather Prediction Center issued a "severe" geomagnetic storm alert for Tuesday. These G4 storms can produce the northern lights, but can also interrupt radio, TV, satellite and cell phone communications.
The northern lights were visible in about two dozen states on Tuesday, one day after many southern states caught a glimpse of the light show on Monday.
Here's a look at pictures from the Pittsburgh area on Tuesday that show the vivid hues of purple, pink, green and blue in the sky.
What causes the colorful northern lights?
Eruptions from the sun, known as coronal mass ejections, occur, and these eruptions interact with Earth's atmosphere and magnetic fields, resulting in a colorful display of the northern lights.
How to see the northern lights
If you missed the northern lights on Tuesday, it's not out of the realm of possibility to see the light show again this year.
When that time comes, you will want to find a dark place with a good view of the northern sky. The lights show up best in pictures, so use "night mode" on your phone.
You can also search for a forecast from NOAA. It shows a 30-minute window of the location and intensity of the aurora.