Complex sentence: In the winter there is infiltration of cold air mass from the polar front, in the winter, the thermometers can come close to 22 degrees F (Farenheit) the city is marked by black ice that decimated the agriculture in 1975.
Split into simpler sentences: In the winter there is infiltration of cold air mass from the polar front, temperatures can come close to 22 degrees Fahrenheit. When this happens, the city is marked by black ice that decimated the agriculture in 1975.