The first public decode of a weather balloon over India

The India Meteorological Department launches a weather balloon every morning. As far as I can find, nobody had publicly decoded one in India. This one was received and decoded on a Raspberry Pi.

Satellite image of a city with the balloon's track coloured by altitude, a dashed gap where the signal was lost, and the descent. — 8 November 2026, coloured by altitude. Dashed: signal lost for 86 minutes, the burst is in there. The track stops at 1.5 km so no house is singled out.

04:44 → 07:19IST, launch to last fix

2 m/sclimb rate, from the decoded GPS altitude

86 minsignal lost, with the burst somewhere inside

The flight

Climbed at 2 m/s, lost at 7.4 km, back at 8.1 km falling, last fix a few metres above the ground.

Done before?

Not from India, as far as I can find (decoder projects, SondeHub, YouTube, Reddit, news). The one exception is across the border: a station in Bangladesh, S21CY, uploads IMD Kolkata's sondes to SondeHub daily.

Network data: SondeHub. Imagery: Esri, Maxar, Earthstar Geographics. Hardware: a hobby SDR and a Raspberry Pi.