Sudden change in weather in the afternoon with a drop in temperatures in most parts of the country is forecast for Monday. The change will initially affect the northwestern parts with heavy storms during the night. Winds will be variable and wind velocity will reach 7 on the Beaufort scale. Temperatures in the north will range from 13C to 35C. Fair on the islands, 20C-33C. Sunny in Athens, 23C-35C; Scattered clouds in Thessaloniki, 19C-31C.