During summer the thermal wind reaches easily 16-20 knots. The thermal wind blows from SW and it is quite frequent and constant. Frontal winds can be very strong (over 30 knots) due to the structure of the Sicilian Channel. NW (Maestrale) is a no-go, get your car and drive to West Sicily (Stagnone or Puzziteddu), other directions are ok. Frontal winds are also quite frequent, especially during spring (mainly S winds) and fall (mainly N winds).