Overview
- NOAA’s Space Weather Prediction Center and the U.K. Met Office have active watches for the CME linked to a Dec. 6 M8.1 flare, with arrival expected around midday Tuesday and peak viewing Tuesday night.
- Forecasts call for Kp values near 5–6 and potential G3 (“strong”) conditions, though outcomes hinge on the CME’s Bz orientation, which will be known only in real time.
- NOAA’s viewlines indicate possible visibility from parts of Alaska, Washington, Idaho, Montana, the Dakotas, Minnesota, Wisconsin, Michigan, northern Iowa and New York, plus Vermont, New Hampshire and Maine.
- Agencies expect limited, manageable effects to satellites, GPS, HF radio and power-grid operations, and advise operators and the public to track SWPC updates and local cloud cover.
- A brief uptick to stronger levels is not ruled out by some outlets, and the viewing window overlaps with the building Geminid meteor shower for skywatchers under dark, clear skies between 10 p.m. and 2 a.m. local time.