Northern Lights spotted over Chicago amid severe solar storm

CHICAGO - For the first time in nearly 20 years, a Severe (G4) Geomagmetic Storm Watch was issued on Thursday, after a series of solar flares were observed.

According to the Space Weather Prediction Center, the Northern Lights could be visible as far south as northern Alabama overnight and early Saturday morning.

Auroras occur when a solar storm emits extra charged particles into space, and those charged particles interact with Earth's atmosphere to create a natural colorful light display in the sky.

Where in Chicago can you view the Northern Lights?

To get a good view, you'll want to get away from city lights and other sources of light pollution. The best time to try to see the Northern Lights will be in the early morning hours of Saturday – by 2 a.m. or 3 a.m.

However, on Friday night, the lights could faintly be seen over the city of Chicago.

A quick-moving low pressure system was forecast to arrive Friday evening, bringing clouds and showers to the area until around 1 a.m. or 2 a.m. Quickly following these showers, the clouds will begin to thin out from northwest to southeast.

Northern lights forecast

You may be able to see auroras, better known as the Northern Lights, as far south as Alabama, the agency says, but they are more likely the farther north you are. You should travel away from cities and lights for best viewing Friday night or early Saturday.

Experts stressed it would not look like the dramatic curtains of color normally associated with the Northern Lights, but more like splashes of greenish hues.

Friday night into Saturday, the FOX Weather Forecast Center says skies look clear for most of the northern U.S. with less than 10% cloud cover expected from the Midwest to the Northwest. However, clouds will be around in the Northeast.

RELATED: 'Severe' solar storm could trigger Northern Lights as far south as Alabama on Friday night

G4 solar storm watch

The National Oceanic and Atmospheric Administration upgraded a geomagnetic solar storm watch from a Level 3 ("moderate") to a Level 4 ("severe") watch after several solar flares combined.

According to NOAA, the explosive acceleration of charged and superheated plasma, known as a coronal mass ejection or CME, speeds through space and expands.

NOAA is calling this an "unusual event," pointing out that the flares seem to be associated with a sunspot that’s 16 times the diameter of Earth.

"Watches at this level are very rare," NOAA stated in the alert.

This is the first "severe" geomagnetic storm watch issued since January 2005.

Effects on power grid, communications

An extreme geomagnetic storm in 2003 took out power in Sweden and damaged power transformers in South Africa.

This weekend, NOAA says a swath of the planet could see a blackout of high frequency radio communications for hours. The geomagnetic storm could also cause widespread voltage irregularities in power systems which trigger false alarms on security devices, cause drag on low earth orbit satellites preventing them from orienting and cause range errors and a loss-of-lock for GPS systems.

What was the Carrington Event?

Earth has experienced space storms throughout its history. Scientific data from ice samples taken from the arctic show evidence of massive geomagnetic storms as early as 774 A.D.

In 1859, the Carrington Event, named after British astronomer Richard Carrington, caused mass terror when it obliterated the entire global telegraph system. Auroras were visible as far south as Colombia in what is considered the largest recorded account of a solar storm to hit Earth.

Telegraph operators reported receiving electric shocks when touching their instruments as telegraph paper reportedly caught fire from the charges.