Summary and Forecast

Geomagnetic Summary and Forecast

Geomagnetic Summary and Forecast


 
The forecast is based on a linear prediction filter applied to ACE data. The prediction fails or looses accuracy for disturbances not directly driven by the solar wind, such as substorms.

Disturbance levels are based on the measured deviation in the Horizontal component (dH):

Tromsø:

Active: dH > 480 nT                          (indicative of K > 4)
Moderate: 160 nT < dH < 480 nT   (indicative of K = 3 – 4)
Quiet: dH < 160 nT                           (indicative of K < 3)

Dombås:

Active: dH > 180 nT                           (indicative of K > 4)
Moderate: 60 nT < dH < 180 nT      (indicative of K = 3 – 4)
Quiet: dH < 60 nT                              (indicative of K < 3)

 

The corresponding provisional K-indices in last seven days

Provisional K-index Tromsø
Provisional K-index Dombås