NOAA SWPC / Event history

ALERT: Geomagnetic K-index of 4

ALERT: Geomagnetic K-index of 4 · Threshold Reached: 2026 Oct 21 0429 UTC · Synoptic Period: 0300-0600 · Active Warning: YES · Comment: · NOAA Space Weather Scale descriptions can be found at · www.swpc.noaa.gov/noaa-scales-explanation

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Bulletin issued: 21 October 2026 at 04:29 UTC
First saved by us: 21 October 2026 at 04:40 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

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First saved record · 21 October 2026 at 04:40 UTC

Saved by us

21 October 2026 at 04:40 UTC

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 04:29 UTC

View saved version 1

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

{
  "id": "swpc:K04A:2026-10-21T04:29:25.873Z",
  "category": "solar",
  "title": "ALERT: Geomagnetic K-index of 4",
  "occurredAt": "2026-10-21T04:29:25.873Z",
  "issuedAt": "2026-10-21T04:29:25.873Z",
  "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 0429 UTC · Synoptic Period: 0300-0600 · 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": "011e903ba4b035cb43057ebb114efebec7a9a00c28620e9fa2a70863f47cb01e"
}

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