Forecaster summary - Issued 2018-12-29T00:07:13

High energy electron flux levels seen at GOES 15 have been suppressed through the UTC day of Friday, probably in part due to compression of the magnetosphere from the unexpectedly strong coronal hole 61.

Relative to recent guidance, the chances of surpassing Active 24-hour integrated electron fluence are now higher, and the peak is likely to be earlier, although any exceedence will probably fall outside day one due to ongoing Active Kp intervals holding the electron flux near background levels early in the day.

Persistence is now judged to be a poor guide, given the roughly 150km/s discrepancy in current and past solar wind speeds related to CH61, so confidence in conditions is therefore lower than usual.