I'm not interested in short term temperature variations but would like to answer a question like "How cold has it been last month?". A histogram of temperature variation is one possibility to answer such a question.
What you will see on my updated temperature page are histograms displaying temperature variation over a month's time period. On Sep. 17th I've relocated the temperature sensor and used a special housing for the sensor itself therefore the first histogram covers a time period from Sep. 17th to Sep. 30th only.
I've published the Matlab Script I've used to generate this type of histogram on my github project page.