A piteraq is a cold katabatic wind which originates on the Greenlandic icecap and sweeps down the east coast. The word "piteraq" means "that which attacks you" in the local language. Piteraqs are most common in the autumn and winter. Wind speeds typically reach 50 to 80 m/s (180–288 km/h; 111–178 mph). On February 6, 1970 the community of Tasiilaq was hit by the worst documented piteraq ever in Greenland (estimated at 90 m/s — about 325 km/h or 200 mph) causing severe damage. Since the beginning of 1970 special piteraq warnings are issued by the Danish Meteorological Institute.