Forecaster summary - Issued 2021-04-24T00:27:01

The current diurnal oscillation of High energy Electron flux (greater than 2MeV) is expected to remain within the High bracket for much of the coming four-day period, given the recent prolonged high speed stream from coronal hole 46.

Activity from CH47 may serve to dent these counts through the UTC weekend. Given current levels however, in all likelihood the soon-to-arrive threat from the 22 April CME should soon restore any depletion in levels after the combination of CH47 and the CME onset, meaning that the coming working week remains Likely to still see resulting Active 24-hour electron fluence.

The presence of a transient in the forecast means that both the recurrence-persistence model and REFM are not thought to offer particularly useful guidance in the period, especially given the likely dominance of the CME on geomagnetism.