Northern lights could be seen in Pittsburgh area tonight

PITTSBURGH (KDKA) — The northern lights may be visible in Western Pennsylvania on Friday. 

First Alert Meteorologist Ray Petelin says it's possible but not guaranteed. The Pittsburgh area typically needs to be close to an 8 on the K-index, which measures the magnitude of geomagnetic storms. Friday we'll be around a 6 or a 7, he says.  

There was a chance the northern lights would be visible on Thursday, but there's an even higher chance for Friday. The K-index will likely be too weak to see them on Saturday.

If the northern lights are visible in Western Pennsylvania, you should look toward a dark spot on the northern horizon. It's recommended you give your eyes a bit of time to adjust to the darkness. 

The northern lights have already graced the Pittsburgh area a couple of times this year. Both the aurora borealis and the Perseid meteor shower were visible one night in August, making for a dazzling celestial show. Green, purple, red and pink hues were also visible in Western Pennsylvania skies back in May.    

What causes the northern lights? 

When a geomagnetic storm occurs, solar wind is sent toward Earth. Charged protons and electrons follow Earth's magnetic field and enter the Earth where the magnetic fields are the weakest: the poles. The electrons smash into all the different molecules that make up our atmosphere, creating a dazzling display of colors in the sky.

It's rare for the northern lights to be seen so clearly this far south. Most of the time, we're lucky if it even happens once a year.

In:
• Pittsburgh