In Italy, a southern European country overlooking the Mediterranean Sea, there are
different types of climate: moderately continental in the Po Valley, cold in the Alps, Mediterranean on coasts and islands, and finally, cool and windy in the Apennines.
Precipitation is between 650 and 1,300 millimeters (26 and 51 inches) per year in the central-northern plains, while in the south it goes down to 400 mm (15.5 in) in the driest areas of Sardinia and Puglia. The mountainous areas are generally more humid, and in upper Tuscany and in the north-east it can exceed 2,500 mm (98 in) a year.
Autumn in Italy is the rainiest season, and floods can sometimes occur in October and November.
July and August are the warmest months, with daytime temperatures around 30/33 °C (86/91 °F) in the plains and along the coasts, and the weather is generally good, except in the Alps, where thunderstorms in the afternoon are quite frequent.
Italy is a
sunny country in the centre-south, where generally more than 2,500 hours of sunshine are recorded per year, while in the north, the amount of sunshine is moderate: there are around 1,800 hours of sunshine per year at the foot of the Alps, and about 2,000 hours in the Po valley.
Even though mild, westerly currents generally prevail, in winter there can be
irruptions of cold air from Eastern Europe, with temperatures around freezing or even below, especially in eastern Italy, while in summer, the hot wind from Africa can bring
very hot periods, with highs of 37/38 °C (99/100 °F) and more, especially in inland areas and in the south.
The climate in detail
Po Valley
In northern Italy, the Po-Venetian plain has a
moderately continental climate. Winters, from December to February, are quite cold, the sky is often cloudy and sometimes fog can form, especially in the western part. Summers, from June to August, are hot and muggy, and sometimes thunderstorms can break out in the afternoon and in the evening, especially in the part to the north of the Po and closer to the Alps.
Relative
humidity is high throughout the year, and the wind is normally weak, especially in the west-central part: being closed on three sides, the Po valley is one of the least windy areas in the world.
Precipitation in the Po Valley is moderate, between 650 and 1,000 millimeters (25 to 40 inches) per year, typically, with two maxima in spring and autumn and two relative minima in winter and in summer.
The Alps protect northern Italy from
cold winds: the northerly wind can sweep away the blanket of mist and fog, but since it descends from mountain slopes, it is heated by compression and takes on the form of
Föhn, a dry and relatively warm wind, which blows even more often in the Alpine valleys. Therefore, cold waves in northern Italy come from eastern Europe. In these cases, sometimes it can even snow, especially in the western part and in Emilia-Romagna.
In
Milan, Lombardy, in the central-western part of the plain, the monthly average temperature ranges from 3.5 °C (38 °F) in January to 25 °C (77 °F) in July. In winter, the temperature is a bit milder than in the surrounding areas due to the city's heat island.
Milan is located in the rainiest part, i.e. the one north of the Po river and not far from the Alps, and receives 945 mm (37 in) of rain per year.
At the northern border of the plain and at the foot of the Pre-Alps, the shores of the
lakes (Maggiore, Como, and
Garda) are slightly milder and less foggy in winter, while in summer the heat is less intense and quite often broken by thunderstorms.
The amount of rainfall is high especially in the lakes of the north-west: in
Como, where the average in January is 4 °C (39 °F), 1,300 mm (51 in) of rain fall per year, with two maxima in May of 160 millimeters (6.3 in) and in August of 135 mm (5.3 in); autumn is rainy as well, and sometimes heavy rains can raise the level of the lake.
On the coast, in Veneto and Romagna, the climate is a little milder, but also windier, since both the cold wind from the north-east, the Bora, and the warm wind from the south- east, the Sirocco, can blow.
In
Venice, the temperature fluctuates between 4 °C (39 °F) in January and 24 °C (75 °F) in July. Rainfall is lower than in Milan, and amounts to 750 mm (29.5 in) per year.
In the Northern Adriatic
Sea, the water temperature becomes pleasantly warm for swimming in summer, especially in July and August, although being a small and shallow sea, it may experience remarkable changes depending on weather condition.
Alps and high mountains
The Alpine Chain, which stretches from west to east separating Italy from central Europe, has a
mountain climate, cold and snowy in winter and mild in summer, when thunderstorms frequently break out. There are many winter sports resorts. In the highest peaks such as Mont Blanc, 4,810 meters (15,781 feet), Monte Rosa, and Matterhorn, there are also glaciers. In Italy, the
snowline is a bit higher than on the northern side of the Alps, and is around 3,000 meters (9,800 ft).
In general, the west-central part of the Alps, exposed to southern winds, receives the bulk of the snow in late autumn and early winter, while the eastern part is more exposed to northern currents, so it receives most of the snow in winter and early spring.
In the weather station of
Plateau Rosa, at 3,500 meters (11,500 ft), on the slopes of Monte Rosa, Aosta Valley, where you can do summer skiing, the average is between -11 °C (12 °F) in February and 3 °C (37.5 °F) in July.
In the mountain resorts, located above 1,000 metres (3,300 feet), winter is cold, while summer is very mild, with some hot days, and possible thunderstorms in the afternoon and in the evening.