Amalfi thunderstorms

Ellen, I don't know as anyone can give you a definitive answer. Every year can be different, as far as number of storms. Every day can be different too; predicted thunderstorms may last all day, a few hours or sometimes fall completely apart, just as at home. They also may occur in one part of the coast but not another, as we experienced one October. It rained from Rome all the way to Naples and onwards to Capri...where the ferry emerged into bright sunshine just short of the pier! It hadn't rained there at all.

And I don't know if this will be reassuring or not but this is a very recent post on TA about some recent rough seas seriously delaying the car ferries between Naples and Capri, and the advice to always have a bad-weather plan B. But also note that the "Destination Expert for Naples" informs that weather bad enough to cancel ferries is infrequent. Oh, and just a rainstorm isn't enough to cancel them; it's more likely to be a WIND event or combo of the two.

https://www.tripadvisor.com/ShowTopic-g1783025-i17866-k13721520-Ferry_Boat_From_Capri_During_Bad_Weather-Island_of_Capri_Province_of_Naples_Campania.html

(Edited a typo)

Like others mentioned, hard to predict. We were there for the month of September 2014. No rain, calm seas, lovely weather. Looking back to previous threads from 2014-15 the weather was pleasant. That said, we take a lightweight waterproof rain jacket with hood. Another item we bring is something for motion sickness in case of rough seas. We have sailed over the years & we don’t leave home without Bonine or facsimile. https://community.ricksteves.com/travel-forum/italy/amalfi-oct-too-late

We were in Italy late Sept. and almost all of Oct. this year. We were along the Etruscan Coast in Tuscany, just east of the island of Elba for a week, so north of the Amalfi region, but for what it’s worth, weather was sunny and fair most of the week Sept. 28 thru Oct. 5. But the night of Oct. 2, starting just after sunset, a violent thunderstorm started. It lasted over 3 hours, with a wide stretch of lightning strikes visible for miles and miles. We didn’t lose power, but the apartment next door did. But that storm was just at night.

The week before, there was a long, drenching rainstorm in Bologna, just that one day that week.

The week after (Oct. 5-Oct. 12), in Umbria, two days of the week were steady rain all day. I realize this is inland and farther north, so may not be too useful for reporting Amalfi conditions. No lightning or thunder, but it did rain on our parade.

Following week was on the Italian western coast again, even farther north, in the Cinque Terre. Sun and no storms. Our final week, Oct. 19 thru 26, Rome was sunny and fair the entire time. So the storms weren’t constant this year, but September (at least late September) did have a huge, heavy rain day, and earlier October had some, as well. Mid and later October was the driest time for us, for where we were in Italy.

Start looking through the videos of vlogger Nicki Positano. She often shows torrential rains and even hail on the Amalfi coast, plus roads getting washed out. Also fog.

We just completed our trip to Italy Oct. 1-16. The middle of the trip included a forecast of 8 straight days of 70% or greater chances of rain. It ended up raining 1 day with light drizzle on another day. Overall we were very fortunate. Be flexible and have the right clothes for hiking. Our 3 days in Amalfi were perfect!
Contrast that with our experience 2 years ago in October, when the gang plank on the boat in Positano was rising and falling 3-5 feet from the dock. They were encouraging and pushing people off the boat. Hilarious and frightening at the same time!

I have stayed on the Amalfi coast in March, April, May, June, September, and October, and more than once in every one of these months, but the only month that I experienced thunderstorms was October.