Forecaster summary - Issued 2025-04-24T00:16:14

High energy electron flux (greater than 2MeV) has been at mostly moderate levels during the last 24 hours. The current HSS is likely to be driving an increase in electron flux below GEO, given the strong wind speeds and recent geomagnetic activity. As the HSS continues to ease a little, and the Van Allen belts relax back towards GEO, diurnally high flux levels are possible by around Days 2 onwards (24 Apr). However, the timing of the increase is low confidence given that the coronal hole is a large feature with a chance of increased geomagnetic activity on day 3 and 4 (26-27 Apr) due to a connection to a HSS from the eastern extent of the CH34/+. This is also complicated by potential CME arrival on day 2 (24 Apr).

The associated 24 hour fluence is currently below Active (1e8 integrated pfu) and has been on a slow and steady rise. A further rise in fluence is possible in the period, with an slight chance of reaching above the Active (1e8 integrated pfu) threshold perhaps more likely from day 2 onwards. MOSWOC REFM appears to have a conflicting trend and is therefor viewed with significant uncertainty.