Central England Temperature Update (part 1)
It's been a while since I last looked at the longest-running temperature record in the world. This update takes us to 31st May 2026
Yes, it was hot over here in the UK last May; and it was particularly hot down here in the South West where we make cider and drive around in tractors (pronounced ‘trakkers’)1. I’ve no idea what the record-breaking record for the UK as a whole was and, TBH, I’m not bothered about this. I’m not bothered for two reasons, these being: 1). the reliance by the UK Met Office on weather station data of such a lowly grade that we may as well throw it in the trash, and 2.) the sheer nonsense we find ourselves bathing in on a regular basis. I recently typed out a short note on this that I’ll reproduce here for convenience. A few days ago, I said this…
Whenever the Met Office announces another record-breaking temperature we ought to stop and consider what it means. If the previous record was set 100+ years ago, well before we invented the SUV, and when atmospheric CO2 was 128ppm lower than it is today, then it’s not saying much for the theory behind climate change.
…and that little rant has bagged me the highest ‘like’ count of any note I have penned to date!
I’m not going to even try discussing the issue of low-grade weather station data, the issue of the Met Office using fake stations, the issue of urban heat islands, and the issue of the Met Office ignoring historic sample bias. That’s the game we’re in these days; in a nutshell they need to tell a story to retain their funding, and that story must match government policy or they’ll be no more. I’m not waffling in a wishful manner nor relying on conspiratorial intel here, but reporting my own experience as a G7 government scientist and high level policy advisor from 1995 – 1999 without saying anything I shouldn’t. You can catch a glimpse of that story here.
OK, so politics aside (and bearing in mind pretty much every single climate dataset is likely rigged in some way), then let us proceed to look at some numbers because that’s what I like doing, and I particularly like the Hadley Centre Central England Temperature (HadCET) dataset. I could say that it is a rather cool dataset, but I’d also have to say that it is a rather hot dataset, but then everyone would groan. Here’s what you’ll find on the landing page:
The CET dataset is the longest instrumental record of temperature in the world. The mean, minimum and maximum datasets are updated monthly, with data for a month usually available by the 3rd of the next month. A provisional CET value for the current month is calculated on a daily basis. The mean daily data series begins in 1772 and the mean monthly data in 1659. Mean maximum and minimum daily and monthly data are also available, beginning in 1878.
These daily and monthly temperatures are representative of a roughly triangular area of the United Kingdom enclosed by Lancashire, London and Bristol. The monthly series, which begins in 1659, is the longest available instrumental record of temperature in the world. The daily mean-temperature series begins in 1772. Manley (1953, 1974) compiled most of the monthly series, covering 1659 to 1973. These data were updated to 1991 by Parker et al (1992), who also calculated the daily series. Both series are now kept up to date by the Climate Data Monitoring section of the Hadley Centre, Met Office. Since 1974 the data have been adjusted to allow for urban warming: currently a correction of -0.2 °C is applied to mean temperatures.
That pathetic correction for urban warming annoys me. It’s almost certainly a fudge, for whenever I’ve looked at historic temperature data these last few years the urban environment has tended to come out a few degrees above the rural environment. But, hey, that’s the climate science grift for you!
Onwards and upwards…
Stop Me & Buy One
Before we get going I ought to mention that the HadCET data are available in several formats, but my preference is for the raw daily values, with the mean daily temperature dating back to 1772, and the maximum/minimum daily values dating back to 1878. There is also a rather useful list of active CET stations dating back to 1853, and I shall be looking at this a bit later on.
Graphs of daily data dating back to 1772 can get a wee bit crowded, so I’ll be boiling these 92,931 daily values down into 3,054 monthly means/minima/maxima as well as 255 annual means/minima/maxima. This is where it gets complicated because we can track the absolute (extreme) value of any daily minimum or maximum, and we can track the mean daily minimum as well as the mean daily maximum over both monthly and annual time frames. All in all we can find ourselves ogling no less than 13 historic time series, and that’s before we consider standard deviations. I guess this is going to have to be a case of stopping me and buying into one particular graph that floats your boat.
