Heat wave day 2, Heathrow Airport about 36C

Posted: July 1, 2015 by tchannon in weather

As expected, see here ,

Day 2 of the June/July 2015 heatwave in England topped out at an hourly mean of 35.9C which will be bumped up by spot noise to >36C, unless the Met Office finds a higher reading from somewhere out of sight. The weather was very humid and under variable cloud, wind SSE which brings it from urban.

No time for neat formatting, from quick SS sort.

3772 2015-07-01Z 14:00:00 na 35.9 Heathrow Airport
3672 2015-07-01Z 16:00:00 na 35.1 Northholt Airport
99080 2015-07-01Z 14:00:00 na 34.8 Wisley Garden
3772 2015-07-01Z 16:00:00 na 34.6 Heathrow Airport
3672 2015-07-01Z 14:00:00 na 34.5 Northholt Airport
99095 2015-07-01Z 15:00:00 na 34.5 Kew Gardebs
3672 2015-07-01Z 15:00:00 na 34.3 Northholt Airport
3772 2015-07-01Z 15:00:00 na 34.3 Heathrow Airport
99095 2015-07-01Z 14:00:00 na 34.2 Kew Gardebs
3772 2015-07-01Z 10:00:00 na 34.1 Heathrow Airport
99057 2015-07-01Z 15:00:00 na 34.1 Woburn (ARS)
3462 2015-07-01Z 12:00:00 na 33.9 RAF Wittering

Quick plot of all station data to 16hr BST (data times UT)
Yesterday’s plot
ZIP of data as CSV

Following written yesterday but not published

Hourly maximum

  • 30.4C @16hrs Northolt Airport, London
    Highest maximum temperature Northolt 30.5 °C
    Issued at: 0003 on Wed 01 Jul 2015
  • 30.4C @16hrs Jersey Airport, Channel Islands
  • 30.2C @15hrs Kew Gardens, London
  • 30.0C @14hrs Jersey Airport, Channel Islands
  • 29.9C @15hrs Heathrow Airport, London

Observation: Both Northholt and Jersey thermometers are close downwind of local heat sources: A40 expressway; building and storage area. The late peak, 16hrs points to phase lag from thermal inertia. Heathrow is slightly better placed with the wind as it was.

Weather collapsed into thunderstorms, lightning, rumbling and slight rain here after cloud built up.

Cleared, right now I can see a full moon though haze.
Later, another rain shower, rumbling.

Forecast: hotter tomorrow, pause, hot Friday.

Written 1st July, had to go out, car thermo soaked in sun read 45C, twin air con condenser cooling fans came on immediately at high speed, almost unknown, happens at 40C. On moving thermo settled at 34C. Hazy sun or cloud, hot and steamy.

Here we go

U.N. warns of risks as Europe enjoys scorcher

The United Nations warned on Wednesday of the dangers posed by hot weather, especially to children and the elderly, as much of Europe sweltered in a heatwave whose intensity it blamed on climate change.

Authorities should give people as much warning as possible of potentially dangerous high temperatures so that they take can precautions, the World Meteorological Organization and the World Health Organization said.

It also reminded people to drink plenty of water.

Tens of thousands of people died across Europe in a 2003 heatwave and again in Russia in 2010.

Post by Tim

  1. tchannon says:

    I’ll add a curiosity, it is also a full moon. There is a known temperature linkage in atmospheric data but I’ve yet to find it in surface data.

    Chilbolton Observatory yesterday showed a surprising amount of noise on insolation data even though here not many miles away I thought it was a clear sunny day. This was probably humidity burning out, hence the building thunderclouds.

  2. michael hart says:

    How’s Gravesend doing? Isn’t that one of the go-to places for records these days?

  3. tchannon says:

    Not with an up estuary wind, East.

    At 11hrs UT the wind swung from E to ESE then back to E
    The temperature rose from ~30C to 33C and then back.

    Data files are linked in the article.

  4. scute1133 says:

    Yes, Michael, you’re right and Tim is quite an expert on Gravesend. I was wondering too.

    Also, in their article today, the BBC quoted the 2003 Faversham “highest ever” temp of 38.5°C. I believe that’s the agricultural college one that we found to be in the middle of a field. Completely unofficial and probably read sporadically by students.

  5. Richad111 says:

    Hah! on this heat wave!


    Warmish yesterday, about 16/17 today, solid overcast, foggy at lunch time.

  6. tchannon says:

    Just checked as best I can, the tide turn seems to match the wind direction wiggle.

  7. rysiekski says:

    anyone got a picture of where the heathrow weather station is ? tks.

  8. Tim

    Telegraph are reporting 36.7C at Heathrow today.


    Can’t find any confirmation at Met Office, who give 35.9C

    Any ideas?

  9. craigm350 says:

    Reblogged this on the WeatherAction News Blog and commented:
    The UK has seen the hottest July day on record, with temperatures hitting 36.7C (98F).

    The Met Office said the reading had been registered at Heathrow – breaking the previous record set in 2006.


    In other news I am declaring the coldest day evah as I stuck my head and a thermometer in an ice bucket, which probably has as much credibility as using a site next to an expressway in Sydney. I mean just look at this pristine environment, what’s not to like?


  10. oldbrew says:

    A steady 22C or so on the beach at Port Logan this afternoon, mainly overcast with a few spots of rain now and then. What’s this about a heatwave 😉


    Looking like this [credit: visitscotland.com]

  11. oldbrew says:

    Other Heathrow news – after report recommends a third runway:

    ‘Airport expansion: What happens next?’

    NB Accuweather also reports 36.7C at Heathrow.

  12. tchannon says:

    Brogdale, err… I know more about that than more than a handful, dossier here with the muck. My problem is copyright, have the photos, don’t have permission.

    The old double screen was wired upright to metal tubes, over a rabbit warren, over ground dessicated by a massive conifer hedge and all in an active work area. Dark stuff spilling into the site from dump mounds.
    The screen (appeared to be poorly maintained) was vanished by the Met Office and replaced by a plastic single, moved a month later.

    Etc., lots.

  13. Stephen Richards says:

    Quote UKMet and BBC. “This is so anormal for the max temp to be at the beginning of July”. Are they all thick as s”(t. The difference in ave temp between the 1st and 20 july (the climatic max) is NOTHING you idiots.
    AND temps were as high in 1976 when Heathrow had less concrete and fewer aircraft.

  14. Stephen Richards says:

    tchannon says:

    July 1, 2015 at 8:13 pm

    It also has a special position near the river but in a spit of land

  15. craigm350 says:

    Heathrow has added an awful lot of concrete since the last heatwave in ’06 with a swathe of new developments (not that H’row ever stops developing but it does seem to have intensified over the past decade). My uncle worked at the airport and loathed hot days there with a passion as the runways were ‘a furnace’ – a few miles away it was bearable.

    At the rate we’re going declaring inappropriate records (or at least stating these records without caveats that thermometers are placed next to ovens) we should count the 40C recorded on centre court yesterday for Murray’s match. I regularly recorded 30+ during the 80’s+90’s in my conservatory (now that was a greenhouse!).

    Tim – rain last night (we skirted the T-Storms) had some nice red dust.

  16. Stephen Richards says:

    WMO definition of a heatwave goes something like : 5 days with a temp 5°C above average. This is not a heatwave its a heat spell

  17. tchannon says:

    “rysiekski says:
    July 1, 2015 at 7:29 pm

    anyone got a picture of where the heathrow weather station is ? tks.”

    Top menu, surfacestations, links to this 3 year old article

    Or click for location via whatever aerial images are available but via this large PDF (11MB) from my own blog

  18. tchannon says:

    “Stephen Richards says:

    WMO definition of a heatwave goes something like : 5 days with a temp 5°C above average. This is not a heatwave its a heat spell”

    A good point.
    I’m not going to edit the article title, causes problems, unless I am too far out of line. Am I?

  19. tchannon says:

    “Paul Homewood says:


    Telegraph are reporting 36.7C at Heathrow today.


    Can’t find any confirmation at Met Office, who give 35.9C

    Any ideas?”

    The Met Office did, I have written an automatic data collection software, downloads and processes. Trip it manually to get recent. Met Office Datapoint.

    It is the hourly Met Office figure. I waited for 4pm readings to be probably (+30 mins and a bit) available and tripped a collect, rapid write he article offline and upload. Any rise after 4 is either a freak or a faulty station.

    The hourly is inflated by capture any brief higher value plus instrument noise, Nyquist matters, etc.

    That’s why the title says about 36C

    The instrument response should mimic mercury in glass inside a wooden whitewashed screen. Actually self coloured PVC screens with PRT and various spotty electronics / firmware.

  20. Thanks Tim, I was looking at the hourly numbers too. It seems a huge difference, but the record figure seems to be all over the place. Maybe it shows how much difference a waft from a jet engine makes!

    The Met link says all figures are provisional and can take up to six months to verify, which makes you wonder why they have rushed out within hours with irresponsible claims

  21. craigm350 says:

    Hadn’t seen this little titbit mentioned –
    Heathrow was the hotspot – both politically and physically – as the mercury clocked 36.7C, the highest in July since records began in the mid 1870s with the introduction of standardised thermometer exposure, and edging out Wisley, Surrey, which saw 36.5C in 2006.

    Great comment under the story which no doubt will censored by morning
    repent you will all die soon. The CAGW is upon you.

  22. tchannon says:

    It wasn’t a clear day, was variable air thickness so its possible there was a brief peak.

    Note yesterday at Northolt which is ~7km away, the hourly and spot were 0.1C different.

    Subtract a degree or two and you will have a fair stab at reality for a fully competent site without urban.

  23. tchannon says:

    The standard data capture is in, for the 24hrs of the 1st.

    Once again it turns out localise temperature oddity is associated with a minor weather front. This explains to very variable visibility too. This happened eg. 2003 when also the heat was originating in continental Europe.

    Plot is not ideal, I ought to produce better work, better than nothing.

    I’ve put the lot inside a zip.
    https://tallbloke.files.wordpress.com/2015/07/report-weather-2015-07-01.zip 1MB

    This includes the Chilbolton check plot, so different I double checked the date..
    Particularly notice the pressure plot does not show the passage of a low pressure centre, a different weather regime was just west of the hot area.
    You can follow this on the Met Office data plots.

  24. […] an ongoing discussion here which will evolve as more data comes […]

  25. The more urbanisation,
    The more heat you create,
    And it helps the alarmists
    Their wild claims to inflate!

  26. rysiekski says:

    thanks for photo. Also can anyone explain why london city airport was 3c cooler than heathrow when you might have thought central london would be hotter than suburbs . maybe london city is on a mountain? Even st james park is 35 [heat island alert] lol http://www.weatheronline.co.uk/weather/maps/current?LANG=en&UP=0&R=310&TYP=tmax&ART=tabelle&LANG=en&DATE=1435748400&KEY=UK&LAND=UK&CONT=ukuk&SORT=3&SI=mph&CEL=C&UD=0

  27. rysiekski says:

    i did get a response from Meto as to why London city was 3c cooler. they said “”It’s all down to the wind direction. It was blowing in from the east/southeast yesterday so temperatures at London City Airport would have been lower due to the influence of a breeze from the North Sea in the morning and the Thames in the afternoon, while Heathrow would have had air that had warmed further as it passed over London. You can see this effect in the maxima for the day; Shoeburyness 26.3C, Gravesend 34.7C, Kew Gardens 35.7C and Heathrow 36.7C” If that is Meto’s logic then this hot air stayed south of the river thames heated up by london all the time till Kew then jumped over to heathrow [and apparently gravesend missed the northsea/thames cooling that london city got?} So all heathrow was then was heat island effect of at least 3c if london warmed it up? London can have a heat island of 6c so its well within bounds. So 100 years ago this temp would not have been reached given the heat island would have been less and there would have been no heathrow airport full of hundreds of hot jets? So this record is actually an artificial record made up of very modern factors without which it would never have happened. Don’t find that caveat in the press. “100 years ago it would have been 34c ”. Which would make london city the real temp because according to Meto it didn’t have the heat island and that temp at london city was 3c lower. So any temp at heathrow from air over london should have a caveat of up to say +5c inflation.

  28. hunter says:

    It is hot in July.
    The end of the world is nigh at hand.

  29. tchannon says:

    Some good additional information turned up last night. This is probably plenty for a new blog post if I can figure out how to merge two sets of image information. As I suspected the normal weather charts etc. did not tell all. This is as I said one of the strange line events which are in history associated with outlier highs.

  30. Anything is possible says:

  31. rysiekski says:

    Meto got back to me so i wrote back thus “Met wrote “Observations have been made at Heathrow for 66 years, making it a valuable long running historical record.” [my words now–>] here are some pics of heathrow from 1950 where we learn “Before the first terminal was completed in 1955, the airport was a collection of tents” http://www.wings900.com/vb/general-squawk-talk/29576-london-heathrow-early-pics.html So not really like with like? heathrow then is not heathrow now so the temperatures can’t be claimed as continuous? Never mind that London heat island has probably increased too?. How much temperature increase do you allow for the extra buildings replacing tents since 1949?” I’d be surprised if they respond now lol. The point is all this hottest ever stuff needs to be challenged and documented because now with screaming headlines in media every co2 kook is coming out demanding action over climate change when in fact its just the London heat island. But i think i made enough of a point now lol!

  32. tchannon says:

    Lovely photos there rysiekski.

  33. oldbrew says:

    Paul Homewood reports: “Record” Heathrow Temperature Not Supported By Nearby Locations


  34. tchannon says:

    There is a technical explanation for why outlier conditions existed very locally. The evidence for that is still pending access to image archives, why I paused.

    For sound technical reasons I do not trust the Met Office.