theweatheroutlook

Remove ads from site

TimS
  • TimS
  • Advanced Member
10 August 2020 09:44:45

Really heating up noticeably here now, but not reflected in the LCY station reading yet. I think we’ll see a big jump at 10.30

Originally Posted by: TimS 


Nope, surprisingly modest rises. 29C at regular early riser Headcorn. Otherwise still low to mid 20s in the SE. Biding its time.

Brockley, South East London 30m asl
Rob K
10 August 2020 09:45:38


 


That's a pretty amazing example, really lucky to see a good one right over a weather station.


The most extreme ones that have temps 70C+ have never been offically recorded (otherwise they would hold the world temperature record). You don't want to be under one of them though. Crops destroyed in seconds and people with instant burns.


 


Originally Posted by: Quantum 


Is there any evidence that this has ever or could ever happen? Even 70C air, which I strongly doubt a heat burst could ever reach, would not burn anybody. I mean, you can sit in a sauna with an air temperature of 90 to 100C quite happily without burning. Wilt crops, possibly, but the damage would be more likely caused by the associated strong winds!


 


I think the world record for tolerating dry air temperatures is something like 400F, as I read many years ago in an old Guinness Book of Records. Heat bursts are characterised by a sudden drop in dewpoint as well as a rise in temps.


 


Edit - yep, 400F with no clothes and 500F "heavily clothed".... 


 


Highest dry-air temperature borne

In US Air Force experiments carried out in 1960, the highest dry-air temperatures endured by naked men was 400F, while heavily-clothed men could tolerate 500F. By comparison, the hottest bearable sauna is about 284F.


 


https://www.thefreelibrary.com/Guinness+Book+of+Records+1999%3A+Part+One+-+Amazing+people%3B+THE+LOOK...-a083099412

Yateley, NE Hampshire, 73m asl
"But who wants to be foretold the weather? It is bad enough when it comes, without our having the misery of knowing about it beforehand." — Jerome K. Jerome
Heavy Weather 2013
10 August 2020 09:46:32


 


Well there is this


https://en.wikipedia.org/wiki/Heat_burst


They are very rare but are almost certainly responsible for the hottest temperatures ever recorded on Earth.


70C+ are possible with them.


Difficulty is they are so rare they haven't happened over an official weather station before, and if they did would it break?


 


Originally Posted by: Quantum 


I think there was a heat burst last year during the July heatwave. Obviously not as spectacular as that.

Mark
Beckton, E London
Less than 500m from the end of London City Airport runway.
Rob K
10 August 2020 09:57:45


London looks on course for 36-37C today.


Originally Posted by: xioni2 


You really think so? I think 34.x will be the limit today; no model that I can see goes above 34.


 


Wednesday is probably the one chance this week of getting 36 anywhere.


 


Having said that Herstmonceux was 4C higher than yesterday at 10am. It seems generally pretty cloudy across the SE today though.

Yateley, NE Hampshire, 73m asl
"But who wants to be foretold the weather? It is bad enough when it comes, without our having the misery of knowing about it beforehand." — Jerome K. Jerome
xioni2
10 August 2020 10:21:56


 You really think so? I think 34.x will be the limit today; no model that I can see goes above 34.


 

Originally Posted by: Rob K 


There is def some uncertainty due to cloud cover, at the moment it's mostly high level, but there is a risk of some mid-level cloud in the afternoon. The wind profile looks much more favourable and temps so far are higher day on day, so we should peak >36C.

Rob K
10 August 2020 10:24:39
Herstmonceux seems to be the new Heathrow! 29.2C at 11am.
Yateley, NE Hampshire, 73m asl
"But who wants to be foretold the weather? It is bad enough when it comes, without our having the misery of knowing about it beforehand." — Jerome K. Jerome
Heavy Weather 2013
10 August 2020 10:26:07

Temperatures starting to surge now I feel.

Mark
Beckton, E London
Less than 500m from the end of London City Airport runway.
Heavy Weather 2013
10 August 2020 10:27:34

Herstmonceux seems to be the new Heathrow! 29.2C at 11am.

Originally Posted by: Rob K 


Is headcorn an official site. That I think might be close to 31C

Mark
Beckton, E London
Less than 500m from the end of London City Airport runway.
Stormchaser
10 August 2020 10:27:35
Generally higher humidity today, more moisture in the air.

Water takes much more energy input than air to raise its temperature by a given amount e.g. a degree Celsius.

So, slower temp climbs can be expected.

On the flip side, moisture also has a ‘greenhouse effect’, so heat won’t escape as readily.

I believe the ‘blanketing’ effect outweighs the heat capacity effect overall, which makes higher max temps achievable for a given amount of sunshine. Not 100% on that, though!
If you have any problems or queries relating to TWO you can Email [email protected]

https://twitter.com/peacockreports 
2023's Homeland Extremes:
T-Max: 30.2°C 9th Sep (...!) | T-Min: -7.1°C 22nd & 23rd Jan | Wettest Day: 25.9mm 2nd Nov | Ice Days: 1 (2nd Dec -1.3°C in freezing fog)
Keep Calm and Forecast On
TimS
  • TimS
  • Advanced Member
10 August 2020 10:27:54

Herstmonceux seems to be the new Heathrow! 29.2C at 11am.

Originally Posted by: Rob K 


Nah, Headcorn's the one: 30C.


For all the focus on Heathrow, so far it's shared the national high temperature once and only been a runner up on other days. Such a shame we've lost Gravesend Broadness though (although not so much the last 2 days with the NE flow).

Brockley, South East London 30m asl
warrenb
10 August 2020 10:28:47
29.5c here now
Tonbridge 45m 
Chidog
10 August 2020 10:36:09


 


Nah, Headcorn's the one: 30C.


For all the focus on Heathrow, so far it's shared the national high temperature once and only been a runner up on other days. Such a shame we've lost Gravesend Broadness though (although not so much the last 2 days with the NE flow).


Originally Posted by: TimS 


Is Headcorn official? It recorded 36.0 on Saturday for instance but this was never mentioned

Rob K
10 August 2020 10:40:09


 


Is headcorn an official site. That I think might be close to 31C


Originally Posted by: Heavy Weather 2013 


I don't think it's an official site. It's not on the map at https://www.metoffice.gov.uk/research/climate/maps-and-data/uk-synoptic-and-climate-stations and I've never seen it mentioned in a daily summary.

Yateley, NE Hampshire, 73m asl
"But who wants to be foretold the weather? It is bad enough when it comes, without our having the misery of knowing about it beforehand." — Jerome K. Jerome
TimS
  • TimS
  • Advanced Member
10 August 2020 10:41:18


 


Is Headcorn official? It recorded 36.0 on Saturday for instance but this was never mentioned


Originally Posted by: Chidog 


It's one of the AWS sites that report METARs each half hour, so I assume so. Didn't see it had registered 36C on Saturday though? It's the only automatic station in the Kentish Weald that shows up on xcweather (though Frittenden is nearby).


 

Brockley, South East London 30m asl
Rob K
10 August 2020 10:44:10


 


It's one of the AWS sites that report METARs each half hour, so I assume so. Didn't see it had registered 36C on Saturday though? It's the only automatic station in the Kentish Weald that shows up on xcweather (though Frittenden is nearby).


 


Originally Posted by: TimS 


Where are you getting the data from? The only Headcorn weather station I can find is this one but it seems to be a private station and very unofficial. It also recorded 36.0C on Saturday. http://www.headcorn.org/html/weather_details.html


 


Googling for Headcorn METAR only brings up data from Lydd.


 


 


The Headcorn site is already reading 32.9C so I suspect it is not a good exposure.

Yateley, NE Hampshire, 73m asl
"But who wants to be foretold the weather? It is bad enough when it comes, without our having the misery of knowing about it beforehand." — Jerome K. Jerome
nsrobins
10 August 2020 10:51:43
When is a station an ‘official’ station ? Always been an issue. If someone could define and clarify this I for one would benefit.
Does the site have to be audited and calibrated routinely to qualify? And by who?If so I guess many of the less formal sites would not count and most of the amateur ones (not just the side of sheds and car sensors).
Neil
Fareham, Hampshire 28m ASL (near estuary)
Stormchaser, Member TORRO
warrenb
10 August 2020 10:54:00
31c here now, so for here on my station that is now 5 days in a row with a temp over 30c.
Tonbridge 45m 
Gusty
10 August 2020 10:58:09

29.3c @ noon here.


30c here we come again. 

Steve - Folkestone, Kent
Current conditions from my Davis Vantage Vue
https://www.wunderground.com/dashboard/pws/IFOLKE11 
Join Kent Weather on Facebook.
https://www.facebook.com/stevewall69/ 



Rob K
10 August 2020 11:04:48

When is a station an ‘official’ station ? Always been an issue. If someone could define and clarify this I for one would benefit.
Does the site have to be audited and calibrated routinely to qualify? And by who?If so I guess many of the less formal sites would not count and most of the amateur ones (not just the side of sheds and car sensors).

Originally Posted by: nsrobins 


I take it to mean the stations that are included by the Met Office in their daily and monthly summaries. Both Met Office-run sites and also the approved private stations, many of which are operated manually so will only be included in the monthly summaries. 

Yateley, NE Hampshire, 73m asl
"But who wants to be foretold the weather? It is bad enough when it comes, without our having the misery of knowing about it beforehand." — Jerome K. Jerome
Rob K
10 August 2020 11:07:36

Worth adding that some of the manual stations will only have the max recorded once a day at 9am GMT, so there could be some higher “official” readings than the ones that are made public and the end of each day, as they won’t get picked up till the following morning.


That happened last year of course, with the Cambridge reading. And I think the 2003 Brogdale measurement came in days or even weeks later (possibly not till the end of the month?)

Yateley, NE Hampshire, 73m asl
"But who wants to be foretold the weather? It is bad enough when it comes, without our having the misery of knowing about it beforehand." — Jerome K. Jerome
TimS
  • TimS
  • Advanced Member
10 August 2020 11:08:52
Widely 18-19C dewpoints today. So a warm night ahead.

I've noticed that Heathrow (currently 17C), and to some extent other sites in the Thames Valley, often see a big drop in DPs in early afternoon on very hot days, when there is a Southerly or SE wind. The direction is due to turn more SE this afternoon so will be interesting to see if it happens. On 10 Aug 2003 (this day, 17 years ago!) it went down if I recall from 18C in the morning to a low of 7C before bouncing back up late afternoon. I thought at the time it might be turbulence from the downs bringing drier, adiabatically heated upper air to the surface. A kind of micro-foehn.

Brockley, South East London 30m asl
The Beast from the East
10 August 2020 11:11:04

My fridge has stopped working I think the vents are iced up due to overwork


Attempting to defrost with a hair dryer

"We have some alternative facts for you"
Kelly-Ann Conway - special adviser to the President
redmoons
10 August 2020 11:12:00
28.5c @ midday | hazy sunshine

Since last thursday, the max / min temperatures are...

06/8/2020 - 29.8c / 14.4c
07/8/2020 - 35.8c / 20.4c
08/8/2020 - 32.2c / 16.9c
09/8/2020 - 33.6c / 17.6c
Andrew,
Watford
ASL 35m
http://weather.andrewlalchan.co.uk 





Rob K
10 August 2020 11:14:09
Heathrow catching up, 30.0C just behind Herstmonceux 30.3C at noon.
Yateley, NE Hampshire, 73m asl
"But who wants to be foretold the weather? It is bad enough when it comes, without our having the misery of knowing about it beforehand." — Jerome K. Jerome
xioni2
10 August 2020 11:16:09

Widely 18-19C dewpoints today. So a warm night ahead.

I've noticed that Heathrow (currently 17C), and to some extent other sites in the Thames Valley, often see a big drop in DPs in early afternoon on very hot days, when there is a Southerly or SE wind. The direction is due to turn more SE this afternoon so will be interesting to see if it happens. On 10 Aug 2003 (this day, 17 years ago!) it went down if I recall from 18C in the morning to a low of 7C before bouncing back up late afternoon. I thought at the time it might be turbulence from the downs bringing drier, adiabatically heated upper air to the surface. A kind of micro-foehn.

Originally Posted by: TimS 


This should happen today with DPs in Heathrow etc. dropping to 13-14C by 4pm when the air temperature will be peaking (36.7C is my lucky guess).


 


 

Remove ads from site

Ads