Scolton Country Park DCNN8156 – Why put a Screen in such a poor location when there were much better ones available?

51.85964, -4.9216 Met Office CIMO Assessed Class 4 Installed 1/1/1989

Scolton Country Park lies 7km/4.4 miles northeast of Haverfordwest in south west Wales. Now a major area tourist attraction the manor started hosting a weather station in 1989 though the Victorian Kitchen Garden there is known to have housed a weather station from shortly after construction in 1840. This same kitchen garden claims to have grown (in 2018) the first pineapple in Wales in over 100 years – such is the effect of these micro climates.

The current screen is away from the micro climate of the walled garden but unfortunately, despite the grounds exceeding 60 acres, the Met office still managed to locate the screen under 10 metres from dense woodland and ended up with a lowly CIMO Class 4 site.

This is not some pedantic nit pick on the part of the World Meteorological Organisation with its International Standards Organisation guidelines, the original Met Office own guidelines recommended a 100 feet (the modern day 30 metres) separation so they really did not even adhere to their own specifications.

The Met office regularly excuses itself for its poor locations as follows

“WMO Siting Classifications were designed with reference to a wide range of global environments and the higher classes can be difficult to achieve in the more-densely populated and higher latitude UK. For example, the criteria for a Class 1 rating for temperature suits wide open flat areas with little or no human influenced land use and high amounts of continuous sunshine reaching the screen all year around, however, these conditions are relatively rare in the UK. Mid and higher latitude sites will, additionally, receive more shading from low sun angles than some other stations globally, so shading will most commonly result in a higher CIMO classification – most Stevenson Screens in the UK are class 3 or 4 for temperature as a result but continue to produce valid high-quality data. WMO guidance does, in fact, not preclude use of Class 5 temperature sites – the WMO classification simply informs the data user of the geographical scale of a site’s representativity of the surrounding environment – the smaller the siting class, the higher the representativeness of the measurement for a wide area. Indeed, it should be noted that WMO Class 5 is not the same as a Met Office ‘Unsatisfactory’ inspection assessment, which ultimately determines the ongoing use of a site. We use the Met Office grading system to determine record verification because; it has historical relevance, covering a wide range of long-standing criteria at UK observation sites, the equipment, and the exposure in a holistic manner and has clear meaning to what is acceptable or not. It tells us how much confidence we have in the data and permits comparisons.”

{My bold, and note there is no quantification to “how much” in terms of “confidence”. For my part, at sites like these and very many more, it is ” no confidence at all”}

The above reads more like a list of excuses for failure rather than genuine reasons. There were over 60 acres of mostly open countryside around Scolton Manor to choose from so why pick on a known compromised point?

There are no street view images available of the screen itself and I could not find any on normal promotional images for the site. In such circumstances I end up trawling through any privately uploaded clips on “Youtube” and in this case got lucky with this one https://www.youtube.com/watch?v=1CjnsOpwLE8 from which the still below has been stripped.

The blurry white box centre image is the Stevenson screen located just 10 metres in front of the line of notably tall trees that are guaranteed to act as windbreaks and cause severe shading effects. The trees are mature and did not just grow overnight. A site that looks poor from aerial imagery appears even worse from ground level. As the video clip goes on to show there are many good locations that could have been used.

On top of this poor siting is the surprising preponderance of weather stations in this area of the UK. As I have pointed out many times, the distribution of Met office sites is more predicated on forecasting requirements than historic climate observations. The south western approaches are key areas for incoming weather fronts thus important to monitor for predictions but no more so for climate reporting than anywhere else. Whilst this Pembrokeshire location has numerous weather stations, other similar sized areas have very few or even none at all.

It is genuinely hard to see the reasoning behind Scolton weather station in its current location. I will not be using any of its data for an historical climate reconstruction.

Source: https://tallbloke.wordpress.com/2026/05/17/scolton-country-park-dcnn8156-why-put-a-screen-in-such-a-poor-location-when-there-were-much-better-ones-available/