31 October 2005
Above-average weather
Today a TV weather presenter told us that today’s top temperature at the Gold Coast was 28˚ – five degrees above average. Average what?
I think this means the daily maximum temperature for the month of October (i.e. the arithmetic mean of all daily maxima from that recording station for every October day since records began). Is it a useful piece of information? Only partly: today is the last day of October and I’m sure the average maximum for 31 October is more than 23˚. We may hear tomorrow that a similar maximum temperature to today’s is less than the average!
Why don’t they use daily averages? There must be enough separate recordings for every day of the year (except perhaps 29 February) to calculate a meaningful average maximum temperature. It makes sense to compare apples with apples, and not with … well, you know!
At least we weren’t told it was five degrees above normal!
