Forecaster summary - Issued 2026-03-20T12:05:20

GOES‑19 high‑energy (>2 MeV) electron flux has reduced from high to moderate levels following the arrival of the 16th Mar CME early today (20 Mar), which will likely suppress electrons at GEO. Further CMEs are likely to arrive Days 1 and 2 (20-21 Mar) which should keep electrons suppressed through much of the period, with a coronal hole fast wind then following.

The associated 24hr electron fluence is currently above the Active threshold (1e8 integrated flux) and is expected to reduce through Days 1-2, but in an uncertain manner. MOSWOC REFM is currently significantly under-estimating the fluence, with observed values expected to reduce closer to predicted model values over the next 24-48 hours. However, a better representative trend looks to be recurrence, which is much closer to observed values and shows a likely drop below the Active threshold, perhaps from later Day 1 (20 Mar).