Forecaster summary - Issued 2018-04-17T00:02:07

The high energy electron flux (greater than 2 MeV) at geosynchronous Earth orbit, has peaked a little lower than yesterday, 4220 pfu at 16/2200 UTC. A slow downward trend is expected over the next few days, before a likely more significant reduction during day 4 (20th) as the next coronal hole (90) becomes geo-effective.

REFM models predict a gradual decline in the 24-hour integrated fluence, with a likely drop below the Active threshold by day 3 (19th). Fluence values are then likely to drop more significantly when coronal hole 90 becomes geo-effective, currently expected to be by the end of day 4 (20th).