Forecaster summary - Issued 2024-04-21T00:13:30

High energy electron flux as observed by GOES16 has persisted at mainly Normal Background levels, with an enhanced solar wind environment due to the CME arrival of 19 April and also the possible hesitant coronal hole fast wind connection to CH25/-.

The above has likely increased electron populations at lower orbits, and as solar wind pressure eases into the new UTC working week, the observed flux at GEO is expected to increase to diurnally reach Moderate, perhaps eventually peaking at High flux. This rationale is low confidence however due to the chance of glancing CME arrivals which may serve to redistribute any increased counts.

The associated 24-hour integrated electron fluence is expected to persist below the Active threshold, but with a Slight Chance of approaching this level later in the period. This would most likely require inbound CME arrivals to miss, allowing the build up of flux.

MOSWOC REFM is not expected to offer useful guidance in the period given glancing CME influence, however should these all miss Earth the upward trend in the next 72 hours is considered reasonable, albeit still peaking below Active.