Electron 2 MeV Integral Flux Alert issued on September 30

An Electron 2 MeV Integral Flux Alert was issued on September 30, 2026, after flux levels exceeded the threshold of 1,000 pfu. The alert was based on data from the GOES-19 station, with the threshold reached at 09:45 UTC and official issuance at 10:04 UTC. The previous day’s maximum flux was reported at 5,622 pfu at 16:20 UTC on September 29.

When the 2 MeV electron flux exceeds 1,000 pfu, it can indicate an elevated risk of minor spacecraft surface charging, which can affect satellite operations in geosynchronous orbit. According to the alert details, the high flux levels were observed continuously, with background levels for the greater than 10 MeV proton flux.

Forecast discussion from NOAA’s Space Weather Prediction Center confirms that the greater than 2 MeV electron flux is expected to remain at high levels through October 1, with a return to normal to moderate levels expected on October 2. No significant solar flare activity or Earth-directed CMEs were reported as the trigger for this event.