Yeovilton WMO03853 – The issues of using aviation sites for climate recording

51.00634 -2.64291 Met Office CIMO Assessed Class 1 Installed 1/1/1964

Yeovilton weather station in Somerset is one of those sites which I am sure the public might query if it were given its full title of Royal Naval Air Station (RNAS) Yeovilton. Although the Royal Navy principally uses helicopters and relatively short take off (or even vertical take off) aircraft, the main runway (08/26) is still 2,292 metres (7,520 feet) long with 04/22 at 1463 metres (4,800 feet). It is one of just 2 main RNAS bases along with RNAS Culdrose though there are other smaller sites notably HMS Gannet at Prestwick.

The entire issue of suitability of aviation sites for climate reporting purposes is one of much debate that I shall continue here.

My review of Culdrose was almost entirely written by reader “HiFast” a former USAF Jet Fighter Pilot and member of the American Meteorological Society who offered his views from both sides of the operational fence. So firstly to contrast with his opinions I will briefly review the site. Tim Channons 2012 review and imagery stands good to this day.

I cannot argue with Tim’s assessment that this site meets the technical requirements of Class 1 as set out by the WMO. I also cannot disagree with his subtle add-on that ” I expected this to be easy Class 1 but it isn’t.” The issue here is not whether the site meets tape measurements, flatness, surrounding vegetation, shading etc but what actually goes on around the screen on a regular basis.

HiFast made this cutting remark that I also cannot disagree with.

” If the Met Office is including aerodrome temperatures in its climate assessments, that’s worthy of ridicule.  The transient spikes in temperatures associated with aircraft operations or zephyr-advected pavement-heated air render those readings unfit for climate use.  For aviators…those inflated numbers are satisfactory.“

Ironically, even the Met Office themselves used to admit to a level of unsuitability of aviation sites.

“It is unavoidable that some sites do not meet all these requirements, particularly where a station set up for one purpose gradually takes on a different role, for example an airport site originally established for aviation observing may become a key synoptic or climate station while suffering the effects of urbanisation.“

What perspective can I offer here to possibly balance the view in favour of such sites given that so many weather stations fall into the “aviation” bracket? Again from the above link

“Aviation Network. Some 130 stations of the Aviation Network, based at airfields, produce half hourly METAR observations (see 4.3) for the requirements of short period aviation forecasting. There is considerable overlap with stations in the Basic Synoptic Network.“

This is rather a large chunk of the overall network to dismiss, however, the purposes of historic climate reporting should not require hundreds of reporting sites providing those used are representative of a wide area i.e. good quality. For example the exceptionally good US Climate Reference Network only consists of 114 sites for the contiguous US states and even adding Alaska and Hawaii only brings the number up to 143. The US at nearly 10 million square kilometres is over 40 times the 244,000 square kilometres area of the UK. On that ratio an improbably low number of 4 sites would suffice but i personally feel 30 would be a more suitable number.

The world’s longest running temperature series – the CET – is currently only operating on three sites though with two of them of rather dubious quality at Class 4 Stonyhurst and Class 4 Pershore College. Only Rothamsted is of good quality and it should be noted that in recent times both Ringway Airport and Blackpool Squires Gate airport have been included. {For those who may feel the CET is being well curated now by the Met office I would state it most certainly is not as evidenced by the late former Vice Principal of the Royal Meteorological society, Philip Eden once establishing a competing system better reflecting the original series intent.}

The demerits of this site need to be studied and just like Shawbury the video evidence is rather damning.

The above clip is of routine and regular operations in which glimpses of the screen pop in and out of shot regularly, most readily identified by the 10 metre wind mast alongside it. It can be assumed that rotor wash is a regular occurrence in and around the screen leading to doubtful quality of readings detected by a rapid responding PRT. These events are certainly not unusual and airshows and displays are regular events at Yeovilton. The site has actually become a tourist attraction with an aviation museum and even a Concorde on display.

This is the level of site activity on an event day.

I do feel it is reasonable to suggest that on balance, however good the CIMO rating, Yeovilton like so many other aviation sites should be avoided.

Source: https://tallbloke.wordpress.com/2025/11/30/yeovilton-wmo03853-the-issues-of-using-aviation-sites-for-climate-recording/