[PaulAJ]

So you've picked a couple of locations and dates at random, and gee, there is more noise than signal in your tiny sample.

Now try doing that systematically. Take the monthly averages over 20 years from a few thousand sites. Don't forget to correct for the urban heat-island effect, which creates a false impression of warming when a city grows out around an airport.

Do that, present your results, and it might be worth taking you seriously.