Liguria owns its lovely climate to its peculiar geographical position. It is a natural amphitheatre facing south and shielded from the cold northern winds by the Alps and the northern Apennines. These very same elements influence winter temperatures, especially on Western Liguria where they range between 10° C and 14° C.
Both Western and Eastern Liguria are generally characterised by a warm temperate climate, though further subdivisions are possible. For instance, along the farthest part of Western Liguria - from Capo Mele to the border with France - you can find even better climatic conditions.
In fact, a recent study by "Il Sole 24 ore" based on 10 different weather parameters (days of sun, days of rain, days of strong wind, humidity, etc) calculated over the period 2008 – 2018, has crowned West Liguria as "Best Climate in Italy" ranked n.1, followed far away by Catania and then Pescara. The complete Report can be seen on the following link: https://lab24.ilsole24ore.com/indice-del-clima/
The orography of Liguria influences considerably the pattern and distribution of rains. Eastern Liguria is affected by sirocco winds that cause bad weather conditions, while Western Liguria is affected by westerlies that allow for more settled weather conditions. In particular, when winds blow from north and north-east, temperatures rise considerably and the rate of humidity lowers. At this stage, the weather in Eastern Liguria is cloudy and rainfall is high, while it is lower in Western Liguria rains. From December to February, the area between Capo Mele and the border with France has lower rainfall than Genoa and slightly higher rainfall than the mountainous area between Chiavari and La Spezia -in this area the rainfall total is sometimes similar to the one registered in North-eastern Italy during the same period of time.
In cases of settled weather conditions, Western Liguria is characterised by Levanters (from East) all along its extent to the border with France. Sirocco winds (from South - South-east) are rare. North-west and west winds are also rare because of the Western Alps. This two phenomena are at the basis of the exceptionally lovely climate of the coastal area between Capo Mele and the border with France. And this is why Western Liguria can enjoy a high number of sunny days - equal, or more, to the one in Southern Italy - even during wintertime.
The sea acts as a thermoregulator and thus there are no substantial differences between the minimum temperatures of the two sides of Liguria, though in winter notable differences can be registered between minimum temperatures in seaside resorts - always above zero - and the hinterland.
During wintertime, the temperature range is low; the number of sunny hours per day is high; and the rainfall is low. The mountains act as a barrier that shields Western Liguria from disturbance, thus differentiating the climate in these two bordering areas. San Remo and its surroundings can actually enjoy a fairly milder climate than nowhere. Snow and harsh temperatures are almost exceptional events along the Italian Riviera.