How much rain the model puts on the steep slopes where the Vernazzola's floods are born — and what it expects next. Not a flood warning.
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Vernazza's worst floods come down the Vernazzola — the stream that drops off the steep slopes behind the village, runs under Via Roma in a covered channel, and empties at the harbour. On 25 October 2011, about 542 mm of rain fell in roughly six hours on these hills; the stream and a hundred small landslides buried Via Roma and Piazza Marconi under metres of mud, and three people in the village died. Rain over the harbour tells you little. What matters is how much is falling up on the slopes, where the water gathers. This page reads a weather model at three points — from the ridge down to the village — so you can see what's been falling where the floods are born, and what the model expects next. It is not a flood warning.
The real warnings come by radio
Autumn is the high-risk season
Almost no rain has fallen along this stretch of the catchment in the last two days.
The model expects almost no rain along this stretch over the next two days.
These are weather-model estimates of rain, not measurements — and rain figures are never a flood forecast.
From the high slopes down to town — the order the water travels. Rain up top can reach the valley hours later; rain in town says little about what is coming downstream.
The steep upper slopes and terraces behind the village, around the Madonna di Reggio path, where the Vernazzola's water first gathers. On ground this steep, rain runs off fast.
The narrow valley the stream runs down toward town. What falls on the ridge passes through here on its way to the village.
Where the Vernazzola runs under Via Roma in a covered channel before reaching the harbour — the stretch that overwhelmed in 2011.
Every figure here is a weather model’s estimate for an area, not a rain gauge and not a river gauge. The model works on a coarse grid — one mountain valley can catch a storm the model spreads across the whole slope, or misses.
“On October 25th, in a few hours, it was washed away by torrential rains and an avalanche of mud, dirt, and debris.”
That experience is the honest frame for this page. Heavy rain on the mountains is a reason to be more watchful; calm skies are never a promise of safety. This page can add context — it can never replace the warning chain above.
Updated 10 July at 0:23. Rainfall figures are model estimates from Open-Meteo (CC BY 4.0), read at the points named above; high-slope points use an elevation setting so the model downscales to that height. No river-level gauge feeds this page — none is publicly available here.