Wind Intensity
0No wind: Queit, smoke straightened upwards
1Soft wind: Leaves vibrate gently, smoke can represents direction.
2Gentle wind: Leaves vibrate with gentle noise, wind can be felt.
3Mild wind: Leaves and branches vibrate incessantly, flag can be unfolded
4Moderate breeze: blow up tiny dirts, paper scraps, small branches vibrate
5cool breeze: treelets vibrate sometimes, ribbles can be seen on the lake's surface
6Strong wind: Trees vibrate vigorously, wires whirring, difficult in holding up umbrella