Land and Resources, Climate

The climate of Italy is highly diversified, with extremes ranging from frigid in the higher elevations of the Alps and Apennines, to semitropical along the coast of the Ligurian Sea and the western coast of the lower peninsula. The average annual temperature, however, ranges from about 11° to 19°C (about 52° to 66°F); it is about 13°C (about 55°F) in the Po Valley, about 18°C (about 64°F) in Sicily, and about 14.5°C (about 58°F) in the coastal lowlands. Climatic conditions on the peninsula are characterized by regional variations, resulting chiefly from the configurations of the Apennines, and are influenced by tempering winds from the adjacent seas. In the lowlands regions and lower slopes of the Apennines bordering the western coast from northern Tuscany (Toscana) to the vicinity of Rome, winters are mild and sunny, and extreme temperatures are modified by cooling Mediterranean breezes. Temperatures in the same latitudes on the east of the peninsula are much lower, chiefly because of the prevailing northeastern winds. Along the upper eastern slopes of the Apennines, climatic conditions are particularly bleak. The climate of the peninsular lowlands below the latitude of Rome closely resembles that of southern Spain. In contrast to the semitropical conditions prevalent in southern Italy and along the Gulf of Genoa, the climate of the Plain of Lombardy is continental. Warm summers and severe winters, with temperatures as low as -15°C (5°F), prevail in this region, which is shielded from sea breezes by the Apennines. Heaviest precipitation occurs in Italy during the fall and winter months, when westerly winds prevail. The lowest mean annual rainfall, about 460 mm (about 18 in), occurs in the Apulian province of Foggia in the south and in southern Sicily; the highest, about 1,520 mm (about 60 in), occurs in the province of Udine in the northeast.