Forecaster summary - Issued 2026-04-21T00:18:33

High energy (>2 MeV) electron flux at GOES19 is currently Moderate to High levels, during its diurnal cycle. While charging of the radiation belt is expected to have occurred as a consequence of the recent high speed stream arrival from CH42/-, this is now lower confidence due to recent geomagnetic activity. However, the observed flux at GEO still has a chance of becoming persistently High, especially as solar winds ease later in the period. 

The associated 24 hour fluence was at Background. As flux recovers on day 1 (21 Apr), fluence will also rise, and is likely to become Active days 2-4 (22-24 Apr). This is supported by 27-day recurrence, although the onset is expected to be a little slower. MOSWOC REFM is slightly over estimating wind speeds which are expected to ease a little quicker than indicated. However, this does not take into account recent geomagnetic activity.