In September 2016 I visited the Environment Canada Weather Station in Inuvik, NWT. I arrived just as they were preparing for the 2300z weather balloon launch, and they let me hang around and take some pictures.
Every twelve hours around the globe, approximatley 800 radiosondes are launched. These weather balloons record temperature, pressure, humidity, and location from the surface all the way up to 100k feet, or higher. These measurement are fed into weather models for long-term weather forecasting. These launches happen worldwide at 1100 and 2300 UTC, which gives the balloon enough time to be up at altitude around noon and midnight UTC.
This is the Vaisala RS92-SGPD radiosonde, which measures location, pressure, temperature, and humidity as the balloon ...Read More →