Tyndrum DCNN 1405 – Definitely a cold site or maybe not.

56.41913 -4.66108 Met Office Assessed CIMO Class 5 Installed 1/01/1990

The remit of the Surface Stations Project was to supply objective and factual assessments of each and every of the over 380 Met Office Synoptic and Climate weather reporting stations. The particular emphasis was on temperature recording accuracy which affects numerous aspects of science, technology and social decisions not least of which is “Net Zero”. Typically reviews centre on higher temperature aspects but obviously cold records are equally important. Tyndrum is not usually a hot place but maybe sometimes?……..

A summer view of this location is quite charming, a rural idyll, but the above -10°C is cold by any UK standards. It is also by no means a remote location, Tyndrum has the distinction in being the smallest village to have two railway stations. These are physically just a few hundred yards apart but being on two separate lines are over 20 miles apart by rail journey.

A curiosity regarding the above day’s data is that the Met Office simultaneously claimed “This site is not reporting observations” as below

This claim seems somewhat odd given that it obviously was (how else would they claim the national coldest temperature of the day?) and its data was available online as below. The Met Office always seem rather sloppy with their online presentation of actual data which contrasts sharply with the slick non data based image they portray.

Back to the site, it is given the lowest CIMO Class 5 rating and judging by the street view image should really be 5S due to the obvious shading. The Ordnance Survey sheet indicates the weather station is at the bottom of a steep valley (the reason for the two separate railway routes) and the cause of likely cold frost pocket formation. This is a very popular area with walkers along the West Highland Way and the weather station itself, alongside St Fillans Priory and Priest’s Well, is a well known landmark. {Anyone with any additional imagery please let me know in comments below}

Obviously this type of site is invaluable for weather reporting in such a key road, rail and even waterway (River Fillan) transport route. However, such low area representation (Class 5) rather calls into question the validity of using its readings to judge long term temperature changes. Furthermore, whilst often Tyndrum records very cold, not that surprisingly, it very occasionally records high temperatures from localised weather effects.

“Scotland has seen the hottest day of the year so far, with the temperature hitting 24.5C.

It was recorded in Tyndrum, Stirling, but forecasters are warning it could get even warmer on Wednesday.

Temperatures could reach 25C in the same spot, according to BBC Scotland Weather.”

To be quoting annual averages from sites so prone to such stochastic extremes is only ever likely to produce unrealistic climate representations. Certainly keep this important site for its original intended purpose but surely there is no real reason to include its data in the historic climate record.

Source: https://tallbloke.wordpress.com/2024/11/29/tyndrum-dcnn-1405-definitely-a-cold-site-or-maybe-not/