So how good is Sigma's temperature measurement? I had a stand-alone electronic thermometer on my bike and found serious latency problems. Say in winter, there would be a considerable temperature difference between the garage and outside. After ten minutes of ride, the thermometer would be still showing a temperature closer to the garage than to the outside. Also, while the thermometer was showing tenths of a degree, it was off by about 1.5F, not very convenient if you wanted to know whether to expect ice melting under your tires or water solidifying into ice.
I have since gone to a bimetal thermometer and it is excellent. The reading moves right away as I pull the bike in front of the garage and it gives local temperature variations during the ride. E.g. the reading goes down when I am on an overpass etc.
I don't really rely on the computer temperature. As soon as its in the sun, the unit pickup heat and the temperature become innacurate.