Wind speeds and directions were measured for the first time in the Mars polar region using the Phoenix lander’s Telltale instrument. Astronomers recorded Easterly winds of approximately 15-20 kilometres per hour during the martian mid-summer. When autumn approached, the winds increased and switched round to come predominantly from the West. While these winds appeared to be dominated by turbulence, the highest wind speeds recorded of up to nearly 60 kilometres per hour coincided with the passing of weather systems, when also the number of dust devils increased by an order of magnitude.