Cloud Altitude at NearSys Station, 24 March 2018

At 5:30 PM MST, NearSys Station was 100% overcast with stratus.

The UAVSonde reported the temperature at ground level was 51.6 F and the relative humidity was 19%. At 400 feet AGL, the air temperature was 49.0 F and the relative humidity was 19%. That's a lapse rate of 6.5 F per 1,000 feet.

According to the thermal imager, the ground temperature was 34 F and the clouds has a temperature of -8 F. Assuming a dry adiobatic lapse of 5.4 F per 1,000 feet, the clouds were at an altitude of 7,800 feet.

Thermal image of the stratus over NearSys Station

Visible image of the same clouds

According to the weather station, the air temperature is 53 F and the dew point is 19 F. Assuming a dry acrobatic lapse rate of 5.4 F per 1,000 feet, the clouds are at an altitude of 6,300 feet.

Averaging the two estimates, the status clouds over NearSys Station have a base altitude of 7,050 feet. According to Wikipedia, straits clouds are no higher than 6,500 feet (2,000 m).