Electron 2 MeV Integral Flux Alert issued on June 8, 2026

An alert was issued for June 8, 2026, after the electron 2 MeV integral flux at geosynchronous orbit surpassed the 1,000 pfu threshold, according to the latest notification from the NOAA Space Weather Prediction Center. The alert was first continued on June 7 at 11:43 UTC and updated on June 8 at 05:16 UTC, with yesterday’s maximum flux reported at 2,874 pfu.

Elevated electron flux levels such as these are known to potentially impact satellite operations by increasing the risk of surface charging, particularly in geosynchronous orbit. High fluxes can pose a hazard to spacecraft electronics but do not correspond to NOAA’s Solar Radiation Storm S-scale, which is based on proton flux levels rather than electron flux. No radiation storm threshold on the S-scale was reached during the period covered by this alert.

The latest SWPC forecast discussion indicated that the high electron flux followed minor solar flare activity, primarily C-class flares from active regions numbered 4456 and 4455. No major Earth-directed coronal mass ejections (CMEs) were observed in recent imagery. The electron flux levels are expected to return to normal to moderate values with the arrival of the CME from June 6, though high levels may return by late June 9 and persist through June 10.