Aurora over the Poles
The Auroral Oval is basically the fallout area of the Aurora over the poles, which expands and retracts with the intensity of the Solar Wind that penetrates, and causes geomagnetic activity, within our atmosphere when the Earth’s magnetic field reverses (see What Causes Aurora).
The oval uses true north, so fallout during less intense Solar Storms leading to Aurora over far northern Europe, say 66° north along the rim of the Arctic Circle over far Northern Europe and North Western Russia, as the planet rotates, will cause Aurora at lower latitudes over the US and Canada.
Image – NOAA Auroral Oval
To understand the Auroral Oval, the NOAA’s Aurora forecasting tool, this displays a changing prediction of the oval using info from the solar wind, and Interplanetary magnetic field (IMF) to give 30 minute forecasts, monitoring this will help you understand how the oval changes, and areas that may receive Aurora during strong solar winds.