Was the Exodus natural or supernatural, fact or fiction?

[Confused Ape]

In the case of Santorini geologists have tracked the ash cloud and the bulk of it moved north east into Asia Minor. The amount of volcanic ash in Egypt is miniscule by comparison which means that there would not have been a sufficient impact on the land to produce these dire plagues. Secondly, the Santorini tsunami is generally attributed to caldera collapse which would have come at the end of the eruption but still long before the bulk of the ash settled on the land...even if the ash had been aimed in the right direction.

I found something interesting on the United States National Library of Medicine.

Medical Papyri Show The Effects Of The Santorini eruption heavily influenced the development of ancient medicine.

Abstract
Exposure to ash from the catastrophic Santorini eruption radically changed Bronze Age medicine, triggering the development of new remedies, the wide dissemination of medical data, and the transfer of technologies. These developments were identified in medical papyri thanks to remedies for ailments linked to volcanic matter an oddity in Egypt, a country without volcanoes. The anomaly was traced back to the Santorini eruption, which through volcanic ash, acidified bodies of waters, and acid rain affected the whole eastern Mediterranean without sparing Egypt. Using available technology, doctors developed new remedies for severe irritation to eyes from ash and for burns on the skin, or imported foreign remedies as exemplified by paragraph 28 of the London Medical Papyrus (L28), thus resorting to technology transfer even if so crude. Furthermore, medical manuals rather than being guarded by families of physicians were now used to disseminate remedies as widely as possible. Finally, besides providing historical data, the medical reaction to the Santorini eruption could still be of use today. The remedies could be integrated in manuals for emergency situations for population left without adequate medical infrastructure at a time of exposure to heavy volcanic fallout or acidified rain.

The 1986 Camaroon disaster really happened.

1986: Hundreds gassed in Cameroon lake disaster

The article includes a photo of the lake which had turned reddish brown.

It looks like the Santorini disaster could have affected ancient Egypt in some ways and people elsewhere could have heard how it had affected other places from travellers.

There's a lot of evidence that the stories of the Egyptian plagues were based on real events. So what? None of it proves that any deity exists. Some religious extremists were claiming that the Boxing Day Tsunami in 2004 was God's punishment but that doesn't mean the tsunami never happened.