Electron 2 MeV Integral Flux Alert issued on October 29

An Electron 2 MeV Integral Flux Alert was issued by NOAA SWPC on October 29, 2026, at 16:14 UTC. The alert continues from an earlier event that began on October 23, 2026, at 11:40 UTC, and remains in effect due to elevated electron flux levels. The maximum observed 2 MeV electron flux reached 2,493 pfu at 18:05 UTC on October 28, 2026.

This alert indicates that the integral flux of 2 MeV electrons has exceeded 1,000 pfu, a threshold for enhanced electron flux events. Such elevated fluxes can pose increased risks to spacecraft operations, potentially causing surface charging and impacts to satellite systems in geosynchronous orbit. Operators in relevant sectors are advised to be alert for possible spacecraft anomalies.

According to the latest SWPC forecast discussion, the greater than 2 MeV electron flux was observed at high levels and is expected to remain elevated on October 29 before decreasing to normal to moderate levels by late October 30 and through October 31, 2026. No significant solar flare or geomagnetic event triggered this alert, as solar activity remains at very low levels with quiet geomagnetic field conditions.