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ALERT: Geomagnetic K-index of 4

ALERT: Geomagnetic K-index of 4 · Threshold Reached: 2026 Oct 21 2059 UTC · Synoptic Period: 1800-2100 · Active Warning: YES · Comment: · NOAA Space Weather Scale descriptions can be found at · www.swpc.noaa.gov/noaa-scales-explanation

Bulletin issued
21 October 2026 at 21:30 UTC
First saved by us
21 October 2026 at 21:40 UTC
Last included in a daily record
21 October 2026

The linked daily edition preserves what we captured that UTC day; this event page is not a live warning.

Source classification
ALERT · Published bulletin

A recent feed check does not mean a new observation. This page preserves source records; it does not establish current safety or warning status.

The saved record

What changed

0 updates · 1 first record

Each update compares two versions we saved. This may not include every update from the source. A missing report does not mean an event has ended.

First saved record · 21 October 2026 at 21:40 UTC
  1. Saved by us

    Starting point

    First saved record

    Our first saved version of ALERT: Geomagnetic K-index of 4. We have no earlier saved version to compare.

    Bulletin issued: 21 October 2026 at 21:30 UTC

    View saved version 1

    Original saved fields, unchanged. This is our record, not an archived copy of the external webpage.

    {
      "id": "swpc:K04A:2026-10-21T21:30:28.363Z",
      "category": "solar",
      "title": "ALERT: Geomagnetic K-index of 4",
      "occurredAt": "2026-10-21T21:30:28.363Z",
      "issuedAt": "2026-10-21T21:30:28.363Z",
      "timeBasis": "Bulletin issued",
      "place": "Space weather",
      "coordinates": null,
      "severity": "ALERT",
      "status": "Published bulletin",
      "summary": "ALERT: Geomagnetic K-index of 4 · Threshold Reached: 2026 Oct 21 2059 UTC · Synoptic Period: 1800-2100 · Active Warning: YES · Comment: · NOAA Space Weather Scale descriptions can be found at · www.swpc.noaa.gov/noaa-scales-explanation",
      "url": "https://www.swpc.noaa.gov/products/alerts-watches-and-warnings",
      "source": "swpc",
      "sourceName": "NOAA SWPC",
      "revision": "753eb4e32ed28797f3baf06771e866a52ab8e8c025c8f1bb47e662795994ca8d"
    }
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