A thermometer in the wind Consider two cases, 
Situation 1: a thermometer is stationary and air is blowing past it.
Situation 2: the thermometer is moving with the wind, say on a car or something.
Assuming now friction between the wind and the thermometer, will the two thermometers read the same temperature?
 A: As heat is essentially a measure of the kinetic energy of the particles in a substance, technically a thermometer with excellent precision would measure a difference.
The particles of air colliding with the thermometer (in Situation 2) will have a smaller relative speed to the thermometer (compared with situation 1), thus their collisions will have lower energy on average, and less heat/kinetic energy will be transferred to the body of thermometer.
This effect can be observed when meteors of high speed travel into the earth's atmosphere, and burn up due to the frictional force created (luckily...).
However, as most thermometers work through the expansion/contraction of some substance due to a heat rise/fall (e.g. Mercury or spirit thermometers), their precision certainly isn't good enough to measure such a change (at typical speeds). Most standard thermometers used in measuring liquid temperatures have suggested submersion levels, in order to minimize errors from heat spikes at the bottom, or expansion/contraction of the glass tubing, so there's certainly a lot of error associated in the readings of these thermometers.
