As the sun continues to display heightened activity, a solar radiation event, strong flare event, and multiple coronal mass ejections (CMEs) have occurred. This increase in solar activity may lead to the northern lights being visible in parts of the U.S. this week. Despite sounding overwhelming, these occurrences are typical during Solar Cycle 25, a phase in which the sun is currently situated.
Solar cycles, which last 11 years, involve the sun reversing its magnetic poles, resulting in space weather such as flares and CMEs. These events, which are eruptions of plasma and magnetic material from the sun, can reach Earth in as little as 15 to 18 hours. According to NOAA, we are nearing the peak of the current solar cycle, as reported by the agency’s Space Weather Prediction Center (SWPC) last month.
Over the past few days, the SWPC has been monitoring various solar activities. Last week, the center detected multiple flares on the sun, which can affect high-frequency radio signals but have minimal impact on the general public. Additionally, the SWPC recently reported minor solar radiation storm and polar cap absorption (PCA) events, both of which have minor impacts mainly on high-frequency radio users and a possible slight risk to space launches.
This heightened solar activity has prompted the SWPC to issue a geomagnetic storm watch extending through Wednesday, as multiple CMEs are expected to arrive at Earth, potentially leading to increased geomagnetic activity. CMEs, as explained by NASA, create currents in Earth’s magnetic fields that send particles to the North and South Poles, resulting in the stunning display of the northern lights.
To gauge the strength of geomagnetic storms, the SWPC uses a 5-point scale, with G1 being the lowest and G5 being the most extreme. As a result of the CMEs, G1 to G2-level geomagnetic storm conditions are expected through Wednesday. These types of storms are not uncommon, as a G2 moderate geomagnetic storm affected Earth last month after a solar material eruption was observed.
Despite no concerns to the general public, there is a chance for residents in northern parts of the U.S. to catch a glimpse of the northern lights. Alaska and much of Canada have the highest chance of witnessing the aurora on Monday and Tuesday, with several states at or above the view line likely having a slim chance of seeing the phenomenon.
The further north one is located, the greater the chance of seeing the aurora when it appears. For residents in southern states, a much stronger geomagnetic storm event would be required to have any possibility of witnessing the northern lights.
Should the geomagnetic storm reach G3 status, residents living as far south as Illinois and Oregon may have the opportunity to see the aurora. However, more severe geomagnetic storms, such as G4 or G5, are much rarer, with solar activity causing these types of storms only a few times per solar cycle.
In southern states such as Florida, Texas, or Hawaii, in addition to a G4 or G5 storm, other factors must align perfectly, including the storm impacting Earth around 8 or 9 p.m., a clear sky, and a view unobstructed by light pollution from cities and towns.
The likelihood of seeing the northern lights in various parts of the U.S. on Monday and Tuesday is detailed in the SWPC’s forecasts, with areas in red having the highest likelihood and those in green having the lowest. The impact and visibility of the northern lights will be determined by the strength of the geomagnetic storm.
Overall, the fluctuations in solar activity bring about the potential for a stunning display of the northern lights, offering a unique celestial spectacle for residents in specific regions of the U.S.