Changes in Temperature and Relative Humidity at Flight Level 4 AGL

On the 29th, the UAVSonde was launched three times to collect air temperature and relative humidity data. The data show the air temperature remaining nearly constant on the ground until the late afternoon. The air temperature aloft increased significantly in the late afternoon. This unexpect result means I need to refly this mission again and with more flights.

The relative humidity on the ground decreased through out the day; but aloft, it increased slightly by evening.