Forecaster summary - Issued 2025-10-29T12:46:49

GOES19 >2MeV electron flux is currently at background to moderate levels. The HSS onset from CH91/92 is later than originally anticipated and so far has been weak. As such, confidence in the strength of this HSS has reduced, and this uncertainty transfers to the electron flux forecast. The flux is still thought likely to see a rising trend during the period, but confidence in the peak strength of this has lowered.

The associated 24 hr fluence is likely to rise in response to the HSS, with a chance of becoming Active by Days 3-4 (31 Oct-01 Nov). MOSWOC REFM shows a gradual rise, however if the HSS gets stronger REFM is likely to start forecasting higher fluence values. The 27-day recurrence is likely overestimating fluence values, as a very strong connection was observed on the previous rotation, resulting in Active fluence being reached during the equivalent of Day 1 (29 Oct). It is also worth noting that Very Active fluence was observed with the enhancement on the previous rotation, and while this would correspond to Day 5 (02 Nov) of this forecast, the strength of the connection is expected to be weaker on this occasion, with lower peak fluence.