ASOS Temperature Sensor
Platinum wire Resistance sensor.
Air drawn past sensor by a small fan.
Sensor shielded to protect from radiation.
Samples once every 30 seconds.
Determines a 1-minute mean.
The last 5-minutes of 1-minute mean values are averaged for a 5-minute average.
Maximum and minimum temperatures are determined from the 5-minute averages and reported at proper synoptic time.