Alert – Electron 2 MeV Integral Flux exceeded 1,000 pfu on August 27

An alert for Electron 2 MeV Integral Flux exceeding 1,000 pfu was issued on August 27, 2026, by the NOAA Space Weather Prediction Center. The alert remains in effect from August 21, 2026, when high electron flux levels were first detected, with the most recent daily maximum recorded at 1,049 pfu at 09:25 UTC on August 27, 2026.

Elevated levels of high-energy (above 2 MeV) electrons in Earth’s outer radiation belt can increase internal charging on satellite components, potentially affecting their operation. Operators of geosynchronous and other high-altitude spacecraft should remain alert for possible impacts during periods when electron fluxes exceed 1,000 pfu.

This heightened electron flux event is taking place during ongoing solar activity, including M-class flares observed from Region 4513, the largest and most complex active region visible on the solar disk. The 24-hour summary indicated that a peak electron flux of 1,650 pfu was measured on August 26, 2026, and conditions are forecast to remain elevated through August 27, with a return to moderate levels expected on August 28–29.