Overview
- An X5.1 flare from active region AR 4274 on Nov. 11 launched a fast coronal mass ejection, prompting NOAA SWPC watches that include a potential G4 geomagnetic storm on Nov. 12 within a G2–G4 outlook through Nov. 13.
- SWPC linked the activity to an R3 (strong) radio blackout earlier on Nov. 11 and reports a moderate S2 solar radiation storm in progress.
- Arrival is forecast from the evening of Nov. 11 into Nov. 12 with high confidence of an Earth‑directed component and only moderate certainty on exact timing and peak intensity.
- Officials caution about disruptions to HF radio, degraded GPS/GNSS accuracy and timing, satellite anomalies and stress on wide‑area power grids, while noting no direct risk to human health.
- Mexico’s UNAM SCIESMEX issued an alert and is coordinating with civil protection authorities, and forecasters say auroras could be visible at unusually low latitudes, including parts of the continental U.S. and northern Mexico.