The weather pattern for the region is that of an oceanic climate (Cfb, according to the Köppen climate classification), with humid and moderate summers and relatively cool winters, although polar air masses from Antarctica are frequent. The average temperatures for January reach 20 °C (68 °F) and 8 °C (46 °F) for July. The West-Southwest winds bring down the temperature below 0 °C (32 °F), while the Southeast ones (the so-called Sudestada) are stronger, producing coastal showers and rough seas, as well as strong squalls, but the cold is much less intense.
There are about 20 days of frost each year, and almost 60 in the west hills area (some 300 mts above the sea level). Snowfall is not uncommon, but snow accumulation on the ground is rare, a phenomenon that takes place every 6 years or so, according to the last 40 year's data.
Among the most best known such occurrences were the 1975 and 1991 snowstorms, but there were also snow accumulations in 1994 and 1997, in the highest hills area of Sierra de los Padres, in 1995 along the southern coast, and other two during the first hours of July 10, 2004 and July 15, 2010.There were flurries in September 1986, June 2007 and July 2011. There is fog in the last days of fall, and springtime is often marred by sea winds and sudden temperature's changes. There are some ten days of 30 °C (86 °F) each summer, certainly milder values than the rest of the pampasregion. Usually, the summer nights are cool and pleasant, with values between 13 °C (55 °F) to17 °C (63 °F). The record high is 41 °C (106 °F) on January 1957 (105 Fahrenheit). The wet season occurs during spring and summer, specially in January, with values between the 70 and 80 mm. The average annual rainfall is 780
