Forecaster summary - Issued 2021-07-29T00:30:33

High energy electron flux (greater than 2MeV) is currently at mainly background levels, perhaps due to the recent slightly elevated geomagnetic activity. Weak enhancements are likely over the next two days, as the near Earth environment stabilises and allows electrons from the current high speed stream to seed the radiation belts. High (1e3 pfu) levels are possible from 29 July onwards on diurnal peaks, but no corresponding increase was observed on the previous rotation, leading to a low probability of a similar increase occurring on this rotation. The forecast possible CME effects on 29 July and 01 August, could also lead to electron redistribution, a compression of radiation belts out of GEO orbit and subsequent suppression of any electron increase.

Electron fluence values are following a sharply declining trend, with this likely to reverse into an increasing trend through the period due to any increase in electron flux. This is subject to any contrary effects indicated above, with a low chance of the Active threshold being reached.