Mark said:
I have such a thermometer too. Usually the accuracy of the
thermometer is so low that the extra digit provides no useful
information. I round those numbers almost automatically. One night the
low was 32F (the actual display was 31.8F).
Mine are very accurate, and yes when I record the
temperature I round it. The real issue is that
most people use thermometers to determine
temperatures that are constantly changing. Check
a digital one with an outside probe attached.
The inside temperature is in a housing that is
heavy enough to act as a heat reservoir so the
temperature changes slowly, while the outside one
has hardly any heat sink.
I have a dual sensor thermometer sitting on a file
case in my office. Under carefully controlled
conditions both the internal and the outside
sensors read the same. In actual practice the
outside and inside sensors seldom read the same
even though the sensors are only 5 inches apart.
I can walk past the sensors (about 2 feet away)
and stir the air enough that the outside sensor
changes 0.4-0.5 degrees.
Outside, temperatures often fluctuate so much that
anything less that a degree makes no sense. I
find it hilarious to listen to the weatherman say
excitedly say that the first freezing night of the
fall was 27 degrees. What he never says is the
period. That low of 27 degrees may have existed
less than a minute and most likely less than 5
minutes and the time below 32 degrees may have
been less than 10 minutes.