Forecaster summary - Issued 2023-04-05T00:15:40

High energy electron flux (greater than 2MeV) is forecast to continue to oscillate between moderate and high (1000 pfu) levels through the forecast period, due to the ongoing high speed stream effects. The British Antarctic Survey radiation belt model (BAS-RBM) is forecasting an increased density of electrons held below GEO, so there is a small chance that a forecast decline in solar wind speeds (and consequently solar wind pressure) could lead to an expansion of electrons towards GEO later in the period. 

Electron fluence values have declined just below Active (1e8 integrated pfu), but with a recent slight increase. The MOSWOC REFM model has until recently been under-forecasting the level of the electron fluence, with a declining trend forecast in the coming days. Overall, it seems possible that fluence may just reach Active levels again in the coming hours, with levels probably staying near or just below Active, although confidence is low. The slight increase in probabilities later in the period reflects the assessment that the radiation belts may relax back towards GEO orbits, bringing increased electron counts.