How to Launch a Weather Balloon

Preparation

• 1

  Attach the radiosonde to bottom of the weather balloon. The radiosonde measures pressure, temperature and relative humidity. Turn on the receiving equipment and ensure the signal from the radiosonde is being picked up.

• 2

  Attach a radiosonde parachute to the radiosonde for safe return to Earth. The parachute should open automatically on descent. If planning a night-time launch, attaching a light stick to the balloon will make tracking its initial flight easier.

• 3

  Secure an addressed mailbag to the radiosonde to enable return if it is found. Please note, The National Service Weather Forecast Office says only 1/5 of the 75,000 radiosondes sent up each year are found and returned, so be prepared not to see it again.

• 4

  Check wind direction, speed and consult the weather forecast for the day. Releasing a weather balloons requires the right conditions. Strong winds could carry the balloon off course, preventing data collection over the required area. It is also important not to release below a storm as this can corrupt the data.

Inflation and Release

• 5

  Fill with either helium or hydrogen. Be careful not to over inflate as this could cause premature bursting. The balloon should inflate to about 6 feet, so inflation should only take place outside.

• 6

  Release the balloon. Ensure the area is free from any overhead obstacles, such as power lines, telephone cables or high-rise buildings.

• 7

  Turn on the receiver and begin collecting data. A weather balloon can rise up to 20 miles into the atmosphere and a flight lasts for about two hours. When a balloon reaches its ceiling height, it expands to about 20 feet before bursting.