Forecaster summary - Issued 2023-05-03T00:08:34

High energy (greater than 2MeV) electron flux as observed by GOES-16 at GEO is expected to continue to follow a generally diurnal cycle through the coming days, likely slowly reducing towards moderate or background levels, but with potential high levels at times of diurnal maxima. Any glancing CME arrivals have the potential to suppress the observed flux further if they occur. However, these are generally expected to miss Earth. By day 3 and 4 (5-6 May) a return to Moderate to Background flux is thought likely with the increasing interacting of the HSS associated with CH99/+ in the southern hemisphere helping to suppress electron activity.

Electron fluence is currently above the Active (1e8 integrated pfu) threshold and is likely to stay that way through the early period, but with an erratically decreasing trend.  Confidence reduces day 3 (5 May) onward, due to uncertainties about how quickly peak flux values will decay, along with the potential for any CME glancing blows and the approach of CH99/+. REFM model output supports a declining trend, however this is currently considered potentially somewhat too quick with its decline.