Athens Heat

There is research that shows passive stations are prone to T biases. However, Stevenson Screen stations are also perfectly reliable if properly maintained despite being fanless. Both Heathrow and Waddington are Stevenson Screen stations from what I understand so there is no reason for their values to be discounted even if not placed in ideal surroundings provided of course they are properly maintained and correctly calibrated to avoid any T biases. Meteorology has relied on Stevenson Screen stations like for ever..

This tweet is not entirely correct. If a Stevenson Screen station is relatively new with modern technology and well maintained then T biases are minimal. However the golden standard is fan aspiration. That's why more and more metoffices around the world are rapidly switching to fan aspirated automatic stations (especially Davis ones). This gives you the advantage to have extremely reliable temperature readings even in the most urban environments.

I think they are checking the readings to make sure everything was ok. As long as the stations are Stevenson Screen or automatic fan aspirated then there is no reason for the readings to be discounted. For example Coningsby is a passive automatic station so there must be a T bias there. Waddington on the other hand seems a Stevenson Screen so I am not sure why people say its been rejected. Especially if we are talking about fan aspirated stations then these are extremely reliable readings even if a station is located in totally urban locations. So far the highest fan aspirated reading I have found for anywhere in the UK yesterday is 39.3C in two Davis stations located in London. However, I have checked only a handful of them. Its a huge task to check one by one all Davis stations in the UK. If anyone has a Davis fan aspirated station which registered over 40C yesterday please let us know!

This is now reported in Ogimet. So I guess equals the record Synop report summary WWW.OGIMET.COM

So, I checked the closest Davis stations from the WeatherLink Network in Coningsby. One reported 40.6C and the other 40.0C Both unfortunately are passive.

It's a huge task to go one by one all the Davis fan aspirated stations today that hit 40+ in the UK. If we find any then I am confident that they would be in urban areas.

Look, I would feel more confident if the record went to a Stevenson Screen station. Out of all the proper 40's today in the UK I think the only Stevenson Screen that is relatively free of criticism is the 40.2C in St. James Park

If you want to find problems with the Coningsby record I can point out the most obvious. It's a passive automatic station. Only difference is that it belongs to the Met Office network.

Υes, 4 out of 5 proper 40s in the London area.

40.3C in Waddington

39C Upton Park, London from the Davis fan aspirated station

39.1C Charlwood

There are 2 Davis stations immediately North of Charlwood registering 38+ right now but they are not fan aspirated.

37.3C the Davis fan aspirated station in Upton Park, London

Where did you get this observation from?I am checking now weatherobs and Charlwood is at 37.3C

Maybe a foehn?

36.1C the Davis Fan Aspirated station in Upton Park, London

35.9C Heathrow

Here is the link for the Davis Fan Aspirated station in Upton Park to look out WeatherLink Home WWW.WEATHERLINK.COM

35.9C the Davis fan aspirated station in Upton Park. Wow!! London is hotting up significantly EDIT: 36C now!!!

35.7C right now the Davis Fan Aspirated station from WeatherLink Network in Upton Park, London

34.6C Kew Gardens

The highest T from a Davis fan aspirated station that I can find right now from the WeatherLink Network is 38.4C at a location called Hollow Farm just outside Cambridge.

35.6C in Upton Park, London Davis fan aspirated station

35.0C from the Davis fan aspirated station in Upton Park, London WeatherLink Home WWW.WEATHERLINK.COM