Forecaster summary - Issued 2021-12-25T12:27:05

The high energy electron flux has been at mainly moderate to high levels due to the input from the high speed stream of coronal hole 35. As this high speed stream declines, the diurnal maximum is expected to decline on days 1 and 2 (25th and 26th), with high levels increasingly unlikely. A more sustained drop in electron flux is expected on day 3 (27th) due to the connection with the high speed stream from coronal hole 37. The increase in geomagnetic activity will result in a redistribution of the electrons within the belts, with the strength of the high speed stream likely to distort the belts out of GEO. A minor recovery in counts may develop through day 4 (28th).

Electron fluence values are following a declining trend, which is reflected in the MOSWOC REFM model. This pattern is accepted through the forecast period, with a decreasing chance of exceeding the Active threshold.