When surface winds are calm, hot air balloon ride pilots can control the altitude of the balloon very finely by heating or venting the air inside. During the day these light surface winds are broken up by “thermals” These are rising columns of warm air that spiral skywards, caused by the heating effect of the sun on the ground. Birds and glider pilots love them but for a hot air balloon; thermals make it very difficult to control the balloon. So the warmer the day the greater the possibility of thermals.
Sunrise and Sunset
These are the optimal times to fly due to the low possibility of thermal activity; largely due to the heating and cooling of the surface. Hot air balloon flights rely on the wind being light for the first few hours after dawn and to decrease before dusk. Both of these situations can provide the opportunity for an enjoyable and safe balloon flight. For a safe balloon flight surface winds must be less than 10 miles an hour during the hour after dawn or before dusk. Of course we have to let our passengers know well before so we have to use forecasts and rely on this information to be able to make the decision to call the flight on. Sometimes the forecast will be wrong and we may on rare occasions have to cancel at the launch site because conditions just don’t work out as the forecasters would have us believe. Or conversely we may end up cancelling a flight that turns out to be flyable, but only with the benefit of hindsight because it was just not predictable with any confidence.
Visibility can be very difficult to predict and is probably the most commonly occurring error in weather forecasts. The different conditions to form mist, fog or low cloud are so subtle that they can vary within a few miles, with a low-lying valley area for example being fogged in and a neighbouring area of elevated land being as clear as a bell.
If visibility issues are relevant to the forecast, our balloon pilot’s will want to access the most up to date information and may also rely on local knowledge.
Our Pilot cancelled and we saw other balloons flying?
Firstly every balloon flights pilot has to make their own judgement of the conditions in which they are confident to fly passengers. SAFETY is our #1 PRIORITY!