Alert – Electron 2 MeV Integral Flux exceeded 1,000 pfu issued on August 22

An alert for Electron 2 MeV Integral Flux exceeding 1,000 pfu was issued by NOAA SWPC on August 22, 2026, at 05:00 UTC. The alert continues from serial number 3724, with high electron flux levels first exceeding the threshold beginning at 11:05 UTC on August 21, 2026. The maximum 2 MeV electron flux reached 1,062 pfu at 04:50 UTC on August 22, confirming persistently high energetic electron activity.

Elevated levels of electron flux at geosynchronous orbit can increase charging risks to satellite components, potentially affecting satellite operations, including anomalies and increased backgrounds in detectors. The alert remains in effect as levels continue above the threshold.

The high electron activity is currently attributed to the influence of a coronal hole high speed stream (CH HSS), as stated in the latest NOAA SWPC forecast discussion. The greater than 2 MeV electron flux is expected to remain at high levels through August 24, 2026, due to ongoing influences from the CH HSS.