The growing interest in non intrusive wireless sensors networks for meteorological, agricultural1, environment monitoring2 has urged the development of miniaturized low power sensors capable of detecting both the wind direction and velocity. Mechanical cup-and-vane anemometers still represent the simplest and less expensive solution when miniaturization and a small detection limit are not required. Ultrasonic anemometers3 are more reliable and robust than mechanical ones but, similarly to the latter, are not suitable to be downscaled below dimensions of several centimeters. Thermal anemometers are precise and sensitive devices that, however, are marked by excessive power consumptions to be employed in battery powered network nodes4. Thermal flow meter with reasonable power consumptions (mW range) and dimensions in the millimeter range can be easily obtained by means of silicon micromachining techniques5 but their intrinsic fragility prevents their direct exposure to wind streams. A possible solution using micromachined thermal anemometers to measure gas flow rates derived from the pressure differences generated by the wind around a cylindrical6 or spherical body. In this way the micro-sensor might operate in a more protected environment, but, with the configuration presented so far estimation of both the wind direction and velocity is not straightforward. In this work we describe an original channel distribution capable of deriving a flow that depends in a sinusoidal fashion on the wind direction. A prototype based on two orthogonal sections equipped with integrated thermal micro-flow sensors have been proven effective in estimating both the wind velocity and direction with simple and reliable calculations.