Fog and clouds can form quickly especially in rio de janeiro as the city is subject to micro-meteorology

Hang gliders can be safely launched, flown and landed in winds from zero to about 30 miles per hour, with ideal winds for launching and landing between 5 to 20 miles per hour depending on the flying site. during flight wind speed is not as important, since the pilot controls the air speed of the glider, independently of the wind speed.

hang gliders use wind lifts to gain altitude and ridge lift occurs when horizontal wind hits a mountain or a cliff and is deflected upward - Thermal lift occurs when the terrain or ocean is heated by the sun transferring heat to the surrounding air which rises and can take the glider with it.