Forecaster summary - Issued 2025-07-22T00:14:44

GOES-19 Electron flux has continued persistently High since 19 Jul, with the outer Van Allen belt seeing some significant charging after the recent fast wind periods. The onset of CH66/- later on day 1 (22 Jul) but perhaps more likely on day 2 (23 Jul), is likely to cause some compression of this belt, along with shedding of some of this charge, and a subsequent drop in observed flux at GEO. This may process may also be further enhanced by the inclusion of any glancing CME, although this is low confidence. Further charging is likely from this fast wind connection however, with some recovery likely through day 3-4 (24-25 Jul), likely rising again to High at diurnal maximum

The associated 24 hour fluence is currently well above the Active level, but has likely seen its peak at 7.67e8 integrated pfu on 21 Jul, with a very slow decline now likely. Any drop out could bring fluence levels below Active for a time of later day 2 and day 3 (23-24 Jul), however these are likely to recover by day 4 with a chance of rising above Active again by the end of the period. However this is low confidence by this stage. REFM is currently suggesting ongoing Active fluence, but continues to under-estimate likely fluence values.