Radiosonde Receiver
Track weather balloons
What it does
SimpleTwice a day, all around the world, weather scientists let go of big balloons that carry a little gadget high into the sky. As the balloon rises — sometimes over 30 km up! — the gadget measures the air and radios the readings back down. Eventually the balloon pops and the gadget parachutes back to the ground.
This app can catch those messages and show you where the balloon is and how high it got. Some hobbyists even chase the landed gadgets like a treasure hunt.
How it works
SimpleThe little gadget under the balloon has its own GPS, just like a phone, plus tiny sensors for temperature and humidity. It packs all that into a radio message and sends it down many times a second. The app catches the messages and reads the balloon's height and position so you can follow its journey up and back down.
How to use it, step by step
Simple- Open the 'Radiosonde' app.
- Set it near 400 MHz.
- Try around balloon-launch times (often early morning and evening).
- Wait for data and watch the balloon's height climb.
- Follow the position as it drifts with the wind.
Examples
Decode a launch, follow its ascent to burst altitude, and predict where it will parachute down.
Watch a single balloon climb past 25–35 km — higher than any airliner flies.
See how the balloon slides sideways with high-altitude winds as it rises.
Tips & things to try
- Launch times cluster around 00:00 and 12:00 UTC — plan your listening then.
- A slightly directional antenna pointed toward the nearest weather station's launch site helps a lot.
- Once a sonde is high up, line-of-sight is huge — you can hear it from very far away.