Aurora forecast – Northern lights forecast

The KP index is a scale from 0 to 9 that provides an indication of geomagnetic activity—meaning how the solar wind affects the Earth's magnetic field. Higher values mean that the atmosphere is exposed to greater solar influence, which increases the likelihood of the northern lights being visible—even further south than usual. This information can be useful for predicting when and where you have the best chance to see the spectacular light show.

The G-scale is a scale from G1 to G5 that provides an indication of the intensity of geomagnetic storms – that is, how strongly the solar wind is disturbing the Earth's magnetic field. At lower values, such as G1, the storms are mild and the effects relatively limited. As the values rise toward G4 or G5, we're talking about strong storms that can not only cause technological disruptions but also increase the likelihood of the northern lights being visible much further south than usual. This scale helps us predict when spectacular aurora experiences might occur, while also alerting us to potential challenges for power grids and satellite communications.

IMF: North-South Direction (Bz) shows the orientation of the sun's magnetic field relative to Earth's magnetic field. When Bz is negative, it means that the sun's magnetic field is directed toward Earth, which increases the transfer of energy to the atmosphere and creates better conditions for strong auroras. Conversely, when Bz is positive, the sun's magnetic field is aligned in the same direction as Earth's, reducing the energy transfer and often resulting in weaker auroras.

IMF: Total Strength (Bt) indicates the overall strength of the sun's magnetic field, regardless of its direction. When the Bt value is high, it suggests that the sun's magnetic field is strong, which can enhance the transfer of energy to Earth's magnetic field. This increases the likelihood of stronger geomagnetic activity and better conditions for visible auroras. Conversely, when Bt is low, the sun's magnetic field is weaker, and the energy transfer to Earth is less efficient, often resulting in weaker auroras.

The speed of the solar wind indicates how quickly solar particles stream from the sun and reach Earth. When the speed is high, it results in a faster and more intense transfer of energy to Earth's magnetic field, which can trigger stronger geomagnetic storms and thus create better conditions for a visible aurora. Conversely, when the solar wind moves slowly, the energy transfer is reduced, and aurora activity is generally weaker.

Solar Wind: Proton Density indicates the number of solar particles—mainly protons—in a given volume of the solar wind. When the proton density is high, it means that more charged particles are hitting Earth's magnetic field, which can increase the energy transfer to the atmosphere. This may lead to stronger geomagnetic disturbances and create better conditions for observing the aurora. Conversely, when the proton density is low, fewer particles reach Earth, reducing the energy transfer and often resulting in weaker auroras.