Checking all SUMOs in the morning, then leave for the cold. We inflate the balloon at the old Aurora station. SODARs were installed next to the station. They measure the air turbulence by means of acoustic signals. Funny beeps with changing frequencies. Sounds like a very cheap bird imitation in the totally silent, almost windless valley.

Gusty winds come up with 10m/s just when the balloon is ready to rise. The balloon has to be brought down and stored in the container.

Meanwhile, the copter was sitting on the ground running with temperature / humidity / pressure sensors. The temperature is quickly floating between -13°C and -9°C. It rises to a steady -8°C when the wind gets stronger. Seems the cold air that slowly flowed from the slopes was displaced by warmer sea air from the fjord.