noun
wind speed
Often used in sailing, fishing, or weather reports to describe how fast the wind is blowing. Can also appear in literary descriptions of wind movement.
今日は風足が強いから、ヨットは出せない。
We can't take the yacht out today because the wind speed is strong.
風足が弱まって、湖面が静かになった。
The wind speed weakened and the lake surface became calm.
風速 is the standard technical term for wind speed in meteorology, while 風足 is more literary or traditional, often used in maritime contexts.
Compound of 風 (kaza, 'wind') and 足 (ashi, 'foot' or 'leg'), literally 'wind legs', referring to the speed or pace of the wind. The exact historical derivation is uncertain, but the imagery is of the wind moving as if it had legs.