The mistral is a strong, cold, northwesterly wind that blows from southern France into the Gulf of Lion in the northern Mediterranean. It produces sustained winds averaging 31 miles an hour, sometimes reaching 60 miles an hour. It can last for several days. Periods of the wind exceeding 30 km/h for more than sixty-five hours have been reported. It is most common in the winter and spring, and strongest in the transition between the two seasons. From Wikipedia