Forecaster summary - Issued 2026-05-01T00:26:54

GOES19 High energy (>2 MeV) electron flux is showing a steady tendency in its diurnal oscillation, staying at mostly moderate levels. This is likely to remain at background to moderate levels as the arrival of the HSS from CH48/- will keep the outer Van Allen belt compressed below GEO. As the HSS begins to ease later in the period there is an increasing possibility of electron flux rising, reaching high levels at the diurnal peak and potentially becoming predominantly high through Day 4 (04 May). Confidence is fairly low however, as recurrence can not be relied upon due to the smaller nature of CH48 on this rotation and subsequently slower wind speeds.

The 24 hour integrated fluence is expected to remain below the Active (1e8 integrated pfu) threshold at first, but with an increasing possibility of breaching Active fluence from Day 2 (02 May)). MOSWOC REFM is forecasting below Active fluence during the next three days, although with an increasing trend which is accepted.