Javascript is disabled on this browser.
Javascript must be enabled for this website to display and function correctly.

Geomagnetic and Solar Activity Forecast Service

The forecasts available are:
  • Daily local geomagnetic activity (DRX index), global geomagnetic activity (Ap index) and solar activity (F10.7 index) for up to 27 days ahead, using a linear prediction method.
  • Daily global geomagnetic activity (Ap index) for up to 3 days ahead, using a non-linear prediction method.
  • Smoothed monthly solar (F10.7 and SSN indices) and geomagnetic (Aa index) activity for the next solar cycle, using a linear prediction method.

Please enter your name and email address

Select the desired forecast from below

To submit the query, press this button: .

To clear the form, press this button: .

Further Information

The DRX index (Daily Range in the X component), in units of nT, is a range index summarising geomagnetic activity that is local to the observatory. It is the average of the 24 hourly ranges in X and not the overall range for the day. The activity classification is a qualitative description of local magnetic activity based on DRX at the observatory. Click for a quick view of the classifications used for each of the three UK observatories.

Daily Ap indices, which are produced using K indices from a worldwide network of observatories, summarise global geomagnetic activity. The observed values of Ap, in units of 2 nT, given in this forecast service are estimates. The definitive values of Ap are provided by GeoForschungsZentrum Potsdam, Adolf-Schmidt-Observatorium für Geomagnetismus, Niemegk, Germany on behalf of the International Service of Geomagnetic Indices (ISGI) of the International Association of Geomagnetism and Aeronomy (IAGA).

Solar activity can be summarised by daily measurements of solar radiation at a wavelength of 10.7 cm (F10.7), given in solar flux units (sfu). The observed values of F10.7 given in this forecast service are from Penticton, Canada and are obtained through the Space Environment Center (SEC), Boulder, Colorado.

The linear 27-day forecasts for the geomagnetic series and solar radio flux have been produced from auto-regressive, integrated, moving-average (ARIMA) models.

Neural net forecasts are available for the index level, and the activity class. Both use time series of Ap and the BGS solar activity index as input data. A different neural net is used for each forecast type.

The long-term predictions of smoothed monthly solar and geomagnetic activity use a modified McNish-Lincoln method constructed from activity cycles 12 and 18 onwards respectively.