Forecaster summary - Issued 2021-09-19T00:15:23

Recent CME effects ought to provoke a rising response in high energy electron flux in the next 24 hours, although the degree to which this occurs is uncertain. The fluence forecast carries a lower than usual confidence, and although it has an upward trajectory it is unlikely to breach the 1e8 Active threshold.

With no more Earth-bound CMEs featuring in the forecast, the triplet of coronal holes CH01, CH04 and CH02 are the only possible drivers of increased electron populations in the period. Being the more well-defined and possibly now signalled as having arrived at STEREO A, coronal hole 02 may be the most significant of these, however this will likely put any electron response beyond the four-day forecast and into the second half of the coming working week UTC.

Neither MOSWOC REFM nor the Recurrence-Persistence model suggest any exceedence of Active fluence in likely in the period, with this general idea accepted.