The weather: the determining element of a balloon's flight

The principle of a balloon is to be a ball of gas lighter than air in the air.

More there is wind, faster it will go and harder it will be to land. Therefore the balloon does not like wind and from a certain speed on, it can neither take-off, nor land ! The wind encompasses two important phenomenons: gusts and the increase in the force of the wind with altitude.

We figure as such that the gust can double the average wind speed and the wind at 150 m in altitude is 50 % stronger than at the surface level. For example, if the wind at the surface is 20 km/h, it is on average 30 km/h with gusts of 60 km/h at 150 m in altitude.

The balloon's other enemy is the storm.
In cases of storm risks, flying is strickly forbidden