Why Adriatic Weather Surprises Experienced Sailors

After more than thirty years of sailing in different parts of the world, I thought I had developed a sound routine for interpreting weather forecasts before and during a passage. Like many experienced sailors, I would carefully examine the wind forecast, pressure systems, expected gusts and sea state before deciding whether to sail, where to anchor, or when to seek shelter.

Then, on a summer passage to Venice, I learned an important lesson.

During the night crossing of the northern Adriatic, we encountered a violent Nevera while still well offshore. Fortunately, we had sea room. As the wind rapidly strengthened in the 50 knots and the storm approached, we decided not to fight it but to bear away and run before the storm in open water under storm jib only. For nearly two hours we stayed well clear of the coast, allowing the worst of the weather to pass before turning back towards the Venetian Lagoon. It was an uncomfortable night, but it ended as a good seamanship story: the crew stayed calm, the boat behaved well, and we reached Venice safely.

Looking back, I was satisfied that we had made the right tactical decisions. The surprise came later...

The following evening, reassured by improving conditions and a forecast showing only moderate winds, we anchored in the narrow Torcello Canal, North-West of Venice. In the middle of the night, another violent convective storm swept through the lagoon. Before we had time to react, the anchor started dragging and the boat was rapidly pushed sideways towards the shallow bank. Within minutes we were aground on the edge of the five-metre-deep canal.

The forecast had not seemed particularly alarming.

Yet the atmosphere still had one more surprise in store.

That experience forced me to ask myself a simple question:

What had I failed to understand?

It certainly wasn’t seamanship. We had reacted correctly in open water and escaped the first storm without damage. The problem was more subtle. I had been looking almost exclusively at the surface weather—wind, pressure and gust forecasts. I had not yet learned to ask the questions that experienced meteorologists routinely ask:

• Is the atmosphere unstable?

• Is there enough moisture to sustain deep convection?

• Is there a trigger capable of initiating thunderstorms?

• Can those storms become organised?

• And most importantly: where will they move relative to my boat?

A few days ago, the same questions came back to mind when several boats were driven ashore during another Nevera at Unije, one of the anchorages I regularly use when sailing from Pula. Many of those crews were almost certainly experienced sailors. Like us in Venice, they probably checked the weather forecast before dropping anchor there.

from Hell in Potkujni. Storm strikes sailors at Unije: moorings torn away and boats crashed onto the rocks

A Croatian sailing friend of mine sent me a picture of a French sailing boat having drifted on shore in the same night.

A picture sent by a Croatian sailor friend from Šibenik on 21st July. Probably an Amel Santorin 46'

The purpose of this series is not to criticise those decisions, nor to suggest that every Nevera can be predicted with certainty. Rather, it is to show that there is another layer of weather information—often available to every skipper—that many of us simply never learned to use.
Learning to read that layer has completely changed the way I prepare for sailing in the Adriatic.
In the articles that follow, we will gradually build that understanding, from the large-scale weather systems that shape the Adriatic, to the local triggers that create Neveras, and finally to a practical decision-making framework that any skipper can use before leaving harbour.