Forecaster summary - Issued 2018-05-11T00:09:27

The solar wind speed from the current coronal hole is now considered to have peaked, meaning that the day-on-day rise in flux levels should now halt before a gradual reduction sets in, manifesting on the 24-hour integrated fluence in the coming hours.

As mentioned in earlier guidance, the REFM model is considered dubious guidance beyond 24 hours - the preferred forecast is to transpose the levels shown near 1e11 beyond 24 hours down two decades to describe a declining trend. This would mean continuation of Very Active through day one, perhaps crossing into Active on days two (preferred) or even three (possible). The proximity of current counts to the threshold makes the precise timing of this crossing difficult to pinpoint, especially given the sensitivity of electron flux to geomagnetic activity. Further activity in this vein is not entirely implausible, especially while the solar wind speed remains elevated and while Bz shows a negative bias.