Forecaster summary - Issued 2018-12-15T00:19:52

The high energy electron flux (greater than 2MeV) has been at moderate to high levels in line with the diurnal cycle. As the solar wind is at background levels this variation is expected to continue today, albeit with a slightly declining peak. The onset of the high speed stream from coronal hole 58 may then increase the electron flux, but this is subject to the redistribution as a result of any significant geomagnetic enhancements.

The corresponding 24-hour fluence has remained very close to the High threshold (1e8 integrated pfu) for the last 24 hours, either slightly above or slightly below the High threshold. The fluence is now expected to remain just above the High threshold (1e8 integrated pfu) for the start of the forecast period, but is then likely to gradually fall below the High threshold through today, perhaps increasing above again during day 3 (17 Dec).