Alert – Electron 2 MeV Integral Flux exceeded 1,000 pfu on April 17, 2026

An Electron 2 MeV Integral Flux Alert was issued on April 17, 2026 after flux levels surpassed the threshold of 1,000 pfu. This continued alert, originating from April 3, 2026, was based on measurements such as a maximum 2 MeV electron flux of 2,407 pfu recorded the previous day. The heightened flux levels were observed at geosynchronous orbit as reported by the NOAA Space Weather Prediction Center.

According to the alert, satellite systems may experience significant charging resulting in increased risk to satellite operations. When the electron flux exceeds 1,000 pfu, such conditions can impact satellite health and longevity due to enhanced internal charging.

The latest official forecast indicated that electrons greater than 2 MeV at geosynchronous orbit continued to reach high levels, with a peak of 3,248 pfu noted on April 15, 2026 at 18:20 UTC. This trend was expected to remain through April 17, with only a brief reduction anticipated on April 18 as a negative polarity coronal hole high-speed stream approaches Earth.