Weekend worsening: Saturday stable, Sunday rain in the Northwest

The weekend will bring a sharp deterioration after days of stability. Saturday, October 17th will still be a largely stable and sunny day across much of Italy, despite some increasing cloudiness in the Northwest and over the Tyrrhenian regions. Only southern Sicily might see some showers in the afternoon.

Sunday, October 18th, however, the situation will change radically with the arrival of a disturbance. Rain will primarily affect the Northwest and some areas of the Tyrrhenian side, with possible thunderstorms. Isolated phenomena are also expected in the South, particularly in southeastern Sicily and Ionian Calabria. Temperatures will see a slight drop in the areas affected by the precipitation.

The incoming weather change marks the end of a high-pressure period that has ensured stable and sunny weather across Italy for several days, with temperatures above the seasonal average. This spell of fine weather was determined by the expansion of an anticyclone over Western Europe and the central Mediterranean.

The arrival of bad weather is caused by a "trough," that is, an area of low pressure descending from Northern Europe. This configuration will push an Atlantic disturbance toward Italy. The trough's particular position, shifted further west, means the regions most exposed to the phenomena will be the northwestern and Tyrrhenian ones, while elsewhere the change will mainly be limited to an increase in cloud cover. The transition will be gradual, allowing for another day of relative stability on Saturday before the worsening conditions on Sunday.