Forecaster summary - Issued 2023-05-23T00:26:11

The high energy electron flux (greater than 2MeV) as observed at GOES-16 has varied from Background to briefly peak at High in the last 24 hours. This is as a consequence of the increase in electrons from the recent solar wind enhancements. However these enhancements have likely also suppressed the observed flux at GEO due to the compression of the Van Allen belt to below this level. While further solar winds enhancements are possible day 1 and into day 2 (23 and 24 May), these are low confidence, with a gradual easing of solar wind pressure expected. This will enable counts to rise at GEO, bringing more persistent Moderate, and increasingly long periods of High flux by day 2.

The associated 24 hour electron fluence is likely to remain below the Active threshold until day 2 (24 May), when there is an increasing likelihood of fluence rising above this level. This rising trend is supported by REFM, which is giving reasonable guidance up to T+24. Beyond this, REFM is currently below the expected observed fluence.