Forecaster summary - Issued 2021-06-17T00:30:31

The high energy electron flux (greater than 2MeV) is likely to start at mainly moderate levels, but is expected to increasingly exceed the high (1e3 pfu) threshold from day 1 (17 June) onward due to the input from the coronal hole high speed stream. This is subject to any geomagnetic enhancements, which may temporarily reduce values as a result of the forecast CME on 19 or 20 June.

Electron fluence values are following a rising trend, with the MOSWOC REFM model predicting a rise above the Active (1e8 integrated pfu) threshold from day 1. This is considered to be reasonable guidance based on the current solar wind environment, with values above the Active threshold then likely through much of the forecast period.