Sri Lanka in the south-west monsoon
Wind Tunnel opens on Sri Lanka in the south-west monsoon, which blows across the island from May to September.
What the satellite saw
No NASA photograph shows a clean vortex street behind Sri Lanka, so this page shows the tunnel's own picture instead. A large island in a monsoon makes a wake that is real but rarely drawn neatly in cloud.
Why Sri Lanka
Size. Sri Lanka is large, about 430 km from north to south; in the tunnel the island's width across the wind sets the Re and the size of the eddies.
Height. Pidurutalagala rises to 2,524 m, high enough to split the monsoon.
The monsoon. Steady from the south-west for four months.
Make it in Wind Tunnel
- Open the link below, or press Sri Lanka under Island: the wind starts from 225°, south-west.
- Press Ink under Look: saffron and pearl dye by which way the water spins.
- Choose 4K and 20 seconds under Save, and press MP4 once the street has formed.