Forecaster summary - Issued 2023-12-05T13:20:10

Electron flux is at background levels with the Van Allen belts still suppressed following recent enhanced geomagnetic activity. Continued suppression is expected as a result of geomagnetic activity associated with the HSS from CH76/-. An increase towards Moderate to High diurnal levels is possible by later Day 2 or Day 3 (06-07 Dec) as the electron belts relax back towards ambient positions. However, the slight chance of a glancing blow from a CME on Day 3 reduces confidence in the forecast. 

The associated 24 hour electron fluence is expected to remain below the Active (1e8 integrated pfu) threshold. However, a rising trend is likely from Day 2 onwards with an increasing chance of exceeding the Active threshold into Day 3 or more likely Day 4 (07-08 Dec). Current REFM forecast is considered to be providing reasonable guidance.