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On May 11, 2024, there was a G5 class geomagnetic storm affecting the Earth. The last event of this class was in October 2003.
The current solar cycle is expected to peak later this year or in early 2025, and end sometime around 2030. Solar flares are much more common during the peak of a cycle than near the end of one, but there are some recorded instances of strong flares late in a cycle.
Any event over the next few days counts as a continuation of the current event for the purposes of this question, unless the causal flare was generated entirely by a different sunspot.
A solar day (a rotation of the sun about its axis) lasts 25 Earth days. The sunspot that generated the May event will soon rotate to the part of the sun that is not facing Earth, but it can come back around in another couple weeks. As far as I am aware, sunspots usually do not continue producing flares at the same strength for this length of time, but if this did occur (in late May or early June), it would count as a separate event for the purposes of this question.
Resolves according to NOAA criteria.
The graph on this page made me confused about whether the October 2024 storm was G5 or not, since the graph of solar storms by month shows a KP9 (G5) storm occured: https://en.wikipedia.org/wiki/Solar_cycle_25
I did a little more digging and discovered that "9" and "9-" are separate classifications, and the October 10 storm was "9-", which maps to G4 and not G5. Putting this here so I don't have to rediscover this if it happens again a few years from now.