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Live forecasts update automatically; written guidance last reviewed 16 June 2026 by the Norwich Wire weather desk. Data from national met services via Open-Meteo.
Live data from Open-Meteo · updates automatically ·
A weather balloon is a latex or synthetic balloon filled with helium or hydrogen, carrying a radiosonde that measures temperature, humidity, pressure and wind speed up to around 35 km altitude. In the UK, the Met Office launches two each day from six stations, including one near Norwich.
Check the live forecast above for current surface conditions at Balloonport – wind speed and direction are critical for a safe launch.
How high does a typical weather balloon reach?
Most weather balloons climb at roughly 5 m/s and burst at an altitude between 30 km and 40 km, expanding as atmospheric pressure drops. The maximum recorded weather balloon height exceeds 50 km, but standard radiosonde flights end around 35 km before the balloon bursts and descends by parachute.
What is the purpose of a weather balloon?
The primary weather balloon purpose is to gather vertical profiles of the atmosphere for numerical weather prediction. Radiosondes transmit real-time data that feed into models used by forecasters on the UK weather hub and for the 10-day weather forecast. Amateur meteorologists and educators sometimes buy a weather balloon kit from Amazon UK or specialist suppliers to conduct their own high-altitude experiments.
Can I buy a weather balloon for sale in the UK?
Yes. Weather balloon for sale options include specialist science retailers and online marketplaces like Amazon. A basic weather balloon kit costs roughly £200–£300, excluding the radiosonde and helium. Always check Civil Aviation Authority regulations before launch.
How long does a weather balloon flight last?
From launch to burst typically takes 90–120 minutes. The descent under parachute adds another 30–60 minutes, depending on wind. Total flight time is usually under three hours, and the payload can travel over 100 km downwind.
What happens to the weather balloon after it bursts?
The balloon fragments fall back to Earth, while the radiosonde descends by parachute. Many are recovered and reused if found. The Met Office publishes predicted landing zones; members of the public can return found radiosondes for recycling.