NOAA Issues ‘Moderate’ Geomagnetic Storm Watch for the Weekend

The Northern Lights, or aurora borealis, appear in the sky over Bifrost, Western Iceland, on March 1, 2017. (Rene Rossignaud/AP)

New York and Chicago residents could see the Northern Lights, or the aurora borealis, over the weekend due to a coronal mass ejection (CME) from the sun, according to U.S. weather officials.

The National Oceanic and Atmospheric Administration (NOAA) posted a map on March 20, saying that a “G2 (Moderate) geomagnetic storm watch is in effect for the 23 March, 2019 ... due to anticipated CME arrival.”

The agency said that an “asymmetric halo CME was observed,” and it appears to be partially directed at the Earth.

A map shows the potential for sightings of the Aurora Borealis over the weekend in the United States (NOAA)

According to the map, the most likely area of an aurora event is between the green line and the yellow line, which appears to encompass parts of New York, northern Illinois (including Chicago), Wisconsin, North and South Dakota, Montana, Idaho, Washington state, Iowa, Michigan, Maine, Vermont, New Hampshire, and Massachusetts.

The very northern parts of Ohio, Pennsylvania, Connecticut, Rhode Island, and Indiana might see the Northern Lights.

“An asymmetric halo CME was observed in SOHO/LASCO coronagraph imagery and initial analysis of the CME in both LASCO and STEREO-A coronagraph imagery shows an Earth-directed component is likely,” the NOAA added.

The NOAA further explained: “The largest storms that result from these conditions are associated with solar coronal mass ejections where a billion tons or so of plasma from the sun, with its embedded magnetic field, arrives at Earth. CMEs typically take several days to arrive at Earth, but have been observed, for some of the most intense storms, to arrive in as short as 18 hours.”

According to CNET, the sun’s solar flare caused some disruptions for radio operators in Africa and Europe. It’s being followed by a CME, which is a massive cloud of charged particles emitted during a flare.

NASA said there is a difference between a solar flare and CME.

“There are many kinds of eruptions on the sun. Solar flares and coronal mass ejections both involve gigantic explosions of energy, but are otherwise quite different. The two phenomena do sometimes occur at the same time—indeed the strongest flares are almost always correlated with coronal mass ejections—but they emit different things, they look and travel differently, and they have different effects near planets,” NASA explained in 2014.

One of the worst solar storms ever recorded was the 1859 Carrington Event, which is said to have created an aurora around the world and caused telegraph wires to erupt into flames, CNET reported. If the same event were to happen today, it could produce disastrous results.

If one wants to witness the Aurora Borealis, travel far away from cities as the light pollution interferes with one’s ability to see the night sky.

The Aurora Borealis (Northern Lights) is seen over a mountain camp north of the Arctic Circle, near the village of Mestervik on Oct. 1, 2014. (Reuters/Yannis Behrakis)

“The Aurora Borealis (Northern Lights) and Aurora Australis (Southern Lights) are the result of electrons colliding with the upper reaches of Earth’s atmosphere. (Protons cause faint and diffuse aurora, usually not easily visible to the human eye),” according to NOAA’s website.

The aurora typically forms some 50 miles to 300 miles above the Earth’s surface, according to NOAA.

Every year, tens of thousands of tourists travel to Norway, Iceland, Alaska, Canada, and other northern areas to see the Aurora Borealis.

Northern lights at Hillesoy Island, Norway. Amateur scientists in Canada have helped researchers discover a new type of northern lights, dubbed “Steve.” (Frank Olsen/Public domain)

But, “when space weather activity increases and more frequent and larger storms and substorms occur, the aurora extends equatorward,” said NOAA. During large solar events, that’s when Aurora Borealis can be observed in much of the United States, Europe, and Asia.

“During very large events, the aurora can be observed even farther from the poles ...  Of course, to observe the aurora, the skies must be clear and free of clouds. It must also be dark so during the summer months at auroral latitudes, the midnight sun prevents auroral observations,” the agency says.