Forecaster summary - Issued 2020-12-09T00:19:47

The high energy electron flux (greater than 2 MeV) is likely to stay below the Alert threshold (1000 pfu) for most of the period, but with a probable rise for Days 3 and 4. The corresponding fluence level will likely remain well below the Active (1e8 integrated pfu) threshold. However, the High Speed Streams related to negative coronal holes 01 and 02 may increase the fluence towards the Active threshold from Day 3 onwards, following the enhancement in solar winds. 

This is supported by the Met Office REFM 3-day forecast and the 27-day recurrence, which strongly suggest levels will remain below the Active threshold. Although on the previous rotation the fluence did rise close to the threshold on the equivalent of day 1. The recurrence-persistence model has probabilities of exceeding Active at between 6 and 7 percent over the period. With an inbound CME and expected high speed stream on Days 1 and 2, these probabilities are considered reasonable, but probably too low from Day 3 onwards.