Forecaster summary - Issued 2020-09-29T00:09:11

The high energy (greater than 2 MeV) electron flux, as observed by GOES-16, reached High levels again today due to the high speed stream from CH82/+. Flux levels are expected to remain mostly above the High threshold (greater than 1000pfu) throughout the period, although further geomagnetic activity over the next 24 hours may temporarily suppress flux values. A sharp increase in flux levels is likely later on Day 1 or on Day 2 (29 or 30 Sep). Solar winds are expected to gradually ease later in the period, with a very gradual declining trend in peak electron flux values likely from Day 3 (01 Oct).

The associated 24 hour fluence is currently above the Active (1e8 integrated pfu) threshold, and expected to continue climbing through Days 1 and 2. This is likely to peak just below the Very Active threshold (1e9 integrated pfu), but with a chance of rising above later on Day 1 or on Day 2, with peak values most likely to occur on Day 2. Whilst fluence values will very gradually decline thereafter, Active fluence will persist through the period. This rising trend, and persistent fluence is supported by REFM. The 27-day persistence from the previous rotation, which saw Active conditions lasting 12 days, also supports an extended period of Active fluence.