Two Atlantic storm systems to bring rain and cold to Italy through 14 November

Two Atlantic disturbances on the way

Forecasters expect two Atlantic disturbances to bring rain to most of Italy this week. Federico Brescia, a meteorologist at iLMeteo.it, says the first front will cross the peninsula between Monday 9 and Wednesday 11 November, while the second, the more structured of the two, will bring widespread rain between Thursday 12 and Friday 13 November. Mario Giuliacci expects a large depression to shape the whole week from Monday 9 to Saturday 14 November, ending an unusually mild spell with a marked drop in temperatures. The forecast for the first wave points to 10 to 20 mm of rain in 24 hours over the north, with snow in the Alps from a line between 1,500 and 1,700 metres. Giuliacci also expects snow on the central-western Alps between Tuesday and Thursday, possibly reaching hill altitudes.

Liguria and Tuscany face the heaviest totals

Liguria is set to take the heaviest rain. Forecasts give 5 to 15 mm in 24 hours there and in the central regions on Tuesday 10 November, followed by 50 to 70 mm in the Spezzino area on Wednesday 11 November. Upper Tuscany is expected to see showers of 30 to 50 mm in 24 hours on the same day. On Thursday 12 November Liguria could be hit by cloudbursts with accumulations of 100 to 150 mm in 24 hours. Tuscany's regional civil protection operations room has issued a yellow alert for hydrogeological and hydraulic risk on minor watercourses, valid from 8 to midnight on Tuesday 10 November. The alert covers Lunigiana, Versilia, Garfagnana and the Lucca area.

Strong winds and rough seas

Winds are set to strengthen as the week goes on. Scirocco and Libeccio are forecast to gust at 40 to 50 km/h on Wednesday 11 November, with waves of 1.5 to 2 metres on the Ligurian and Tyrrhenian seas. On Thursday 12 November Libeccio gusts could reach 60 to 70 km/h, with waves of 2.5 to 3 metres in open water. Rai's outlook warns of winds up to 90 km/h and of rain accumulations up to 100 mm across the week. The sea state is also expected to rise as the second disturbance approaches.

The satellite images from Sunday 8 November showed what Giuliacci calls a 'majestic and powerful Atlantic cyclone', with its typical comma-shaped cloud. He explains that the air cannot pile up inside the depression and is pushed upward, where it cools and forms cloud and precipitation.

“That is why 'cyclones' are synonymous with 'bad weather'.”

Timing and the end of the spell

Brescia expects instability to persist into Friday and early Saturday over the central and southern regions, with a gradual improvement from Saturday afternoon as the system moves east. Giuliacci expects fine weather to return from the following week. Il Messaggero says the spell could run into the weekend, in what it calls an 'estate di San Martino' of storms, even though the saying usually promises mild, dry weather.