FT Wind Sensors have a maximum heating power consumption of 30V and 6A, giving an effective heater capacity of 180W.
Due to the size of the sensors (FT742-DM @ 380g) this gives a very high heating power : mass ratio of 0.47 Watts per gram.
For comparison, if you had a heavier 1.6kg sensor with 240W of heating power this would only be 0.15 Watts per gram; ~30% as effective as an FT wind sensor.
This is why FT Wind Sensors are chosen for cold-climate, data-critical applications and make frozen sensors a thing of the past.