Geomagnetic Storm to Bring Northern Lights Further South on March 19-20

A powerful geomagnetic storm is underway, potentially bringing the aurora borealis – commonly known as the northern lights – to unusually low latitudes. The National Oceanic and Atmospheric Administration’s (NOAA) Space Weather Prediction Center (SWPC) issued a G2 geomagnetic storm warning for March 19 (UTC), with G1 conditions expected to continue into March 20, as multiple coronal mass ejections (CMEs) impact Earth.

What is a Geomagnetic Storm?

Geomagnetic storms are disturbances in Earth’s magnetosphere caused by solar activity, specifically coronal mass ejections (CMEs). CMEs are large expulsions of plasma and magnetic field from the Sun. When these reach Earth, they can interact with our planet’s magnetic field, causing a range of effects, including auroras.

Aurora Visibility Forecast

The predicted G2-level storm could bring the northern lights as far south as Novel York and Idaho. There is also a possibility that conditions could escalate to G3 levels, potentially extending visibility even further south into mid-latitude regions like Illinois and Oregon . The aurora is typically observed as a green oval centered on Earth’s magnetic pole, turning red when more intense .

It’s important to note that even during strong geomagnetic storms, aurora visibility is not guaranteed. Optimal viewing conditions require clear skies and minimal light pollution.

Understanding the G-Scale

Geomagnetic storms are classified using a G-scale, ranging from G1 (minor) to G5 (extreme). Here’s a brief overview:

• G1 (Minor): Weak power grid fluctuations, minor impacts on satellite operations, and auroras visible at high latitudes.
• G2 (Moderate): High-latitude power systems may experience voltage alarms, long-duration storms may cause radio blackouts on high-frequency radio, and auroras visible to mid-latitudes.
• G3 (Strong): Power system voltage fluctuations, sporadic HF radio blackouts, and auroras visible at lower latitudes.
• G4 (Severe): Widespread voltage control problems, significant HF radio blackouts, and auroras visible on a broad scale.
• G5 (Extreme): Complete power system collapse, widespread and long-lasting HF radio blackouts, and auroras visible globally.

Impacts of Geomagnetic Storms

Beyond the visual spectacle of the aurora, geomagnetic storms can impact various technologies:

• HF Radio Communication: Geomagnetic storms can disrupt high-frequency radio communications.
• GPS/GNSS Satellite Navigation: Accuracy of GPS and other satellite navigation systems can be affected.
• Electric Power Transmission: Ground-induced currents can impact electric power grids.

Where to Uncover More Information

For the latest updates and forecasts, you can consult the following resources:

• NOAA Space Weather Prediction Center – Aurora Viewline
• NOAA Space Weather Prediction Center – Aurora 30 Minute Forecast
• SpaceWeatherLive.com

The aurora is an indicator of space weather and provides situational awareness for a number of technologies. It is closely related to the ground-induced currents that impact electric power transmission.