Many places 10°C or more cooler

Figure 1

Many places across England and Wales were up to 10°C or more cooler on Thursday (22 June) than they were or Wednesday (21 June). Trawsgoed in Ceredigion, was top of the list and 12.5°C colder (fig 1). Rather surprisingly, places on the northeast coast of England were almost 5°C warmer on Thursday, once they had lost Wednesday’s sea breeze (fig 2).

Figure 2

Apparently, it’s the hottest June day since 1976 in the UK

Figure 1 – Courtesy of the Met Office and Twitter

Not a lot of people know this, but according to Twitter (fig 1) apparently this afternoons maximum of 34.5°C at Heathrow, make today the warmest June day since 1976 in the UK. All the weather presenters are very excited about all this, so I thought I would get in on the act, and take a wander down memory lane to see what the charts looked like back then. According to the TORRO website the three days with temperatures above 35°C in June 1976 were:

  • June 26  35.4  North Heath (W Sussex), East Dereham (Norfolk) 1976
  • June 27  35.5  Southampton-Mayflower Park 1976
  • June 28  35.6  Southampton-Mayflower Park 1976

I have SYNOP reports for main synoptic hours back to 1973, but unfortunately, in the older SYNOP format temperatures were reported in whole degrees, so it’s not possible to pinpoint the exact maximum at any SYNOP station on these days (figs 2, 3 & 4).

  • I can’t corroborate the reports at North Heath and East Dereham on the 26th, because neither are SYNOP stations, although both Heathrow and Southampton reported 35°C on that day.
  • The Southampton temperature of 35°C on the 27th fits with the TORRO maximum temperature of 35.5°C because the value would have been thrown to the odd.
  • The highest maximum on the 28th at Southampton was reported as 34 in the SYNOPs that I have so I don’t know what’s going on there.

Both the 26th and 27th were very similar days synoptically (figs 5 & 6), with a large anticyclone over Ireland (~1028 hPa) and a ridge eastward extending across the north of England and the North Sea, with a light or moderate E’NE flow over southern England. No real weather to speak of although there was a thunderstorm reported at Exeter on the 18 UTC chart on the Sunday (27th) with a pressure of 1027.6 hpa which is pretty good going (fig 6).

Figure 5

Figure 6

Here’s this afternoons chart for 14 UTC on June the 21st (fig 7), synoptically quite different from June 1976, with high pressure in the German bight (~1020 hPa), low pressure to the NW and trough and cold fronts coming into western Ireland, there is a light to moderate SE’ly flow over southern England this afternoon.

Figure 7

I wonder just how many more hectares of buildings, concrete and tarmac there are surrounding the Stevenson screen at Heathrow compared with 40 odd years ago. I personally think that climate stations and busy aerodromes aren’t a good fit, but historically that’s how the observing network the Met Office now manages evolved.

Figure 8

Maximum temperature of 49.7°C Nuevo León in Mexico

Figure 1

I heard Eddie Mair going on about the temperature in Phoenix Arizona in yesterday evening’s PM program on BBC Radio 4, so I thought I’d keep an eye out on the maximum temperatures and see what turned up. Well to trump Phoenix (no pun intended) the maximum temperature reported at 00 UTC from Nuevo León in Mexico was 49.7°C (121.4°F), and a shade (I can’t help it) higher than the 48.3°C in Arizona. Excuse the contouring of temperatures is far too smooth and not accurate.

36.8°C at Le Mans

Figure 1

Jersey airport ended up being the warmest place in WMO block #03 as suspected with 32.4°C, but Le Mans was the hottest place in France with 36.8°C this afternoon. That air over France will start to feed up across the channel as the gradient starts to veer overnight and possibly produce an even hotter day tomorrow across the south.

Figure 2

Warmest June day here since at least 2004

Jersey looks like taking the crown today as the warmest SYNOP station in WMO block #03, with a temperature just over 90°F at 14 UTC (fig 1).

Figure 1

Here in Bradninch mid-Devon, the temperature has been hovering around 30 or 31°C for much of the afternoon, so to escape the sun that I’d string some code together and look at a couple of thermographs since Saturday for Exeter (fig 2) and Heathrow (fig 3).

Figure 2

Not bad going for Devon, when you consider that Exeter is always starting several degrees cooler than Heathrow each day. I think the sea breeze just kicked in time to prevent the temperature at Exeter airport possibly exceeding 31°C at 14 UTC, as it did here in Bradninch. My Vantage Pro has been recording temperature since September 2004 and this afternoon’s max of 31.3°C makes it the warmest June day in that time.

Figure 3

Phew, what a scorcher!

Figure 1

I count 26 stations with 30°C or higher today, and tomorrow, particularly in the southwest it may be even a little hotter again (fig 1). With temperature as high as 32°C, which they’ve been in the London area this afternoon, which could trigger one or two isolated thunderstorms in places.

Figure 2

17 June 2017 – maximum temperatures

High of 41.4°C in Córdoba

Figure 1

It looks like it will be another very hot day for mid May in Córdoba, Andalusia Spain, although it may not top the 41.4°C (106.5°F) that it reached their yesterday (fig 1). It looks like temperatures have been on the rise in that part of Spain for the last four days or so (fig 2).

Figure 2

According to the climate information in Wikipedia from the Agencia Estatal de Meteorología, yesterdays maximum of 41.4°C (fig 3) was still a long way short of the existing June all time maximum of 45.0°C.

As is fairly typical for Iberia it’s also been fairly sunny in Spain this May, and at the moment Córdoba is also probably the sunniest place in Europe, with over 164 hours of sunshine in the first 12 days of May (fig 4).

Figure 4

More reminiscent of early Autumn than early summer

Quite a week of weather coming up for the British Isle in the next week, if these latest GFS forecast frames are anything to go by. Very mobile till the weekend, with a pulse of very warm air for Saturday and Sunday thrown in for good measure. The gradient over northeast Scotland looks very tight on Wednesday, and there’s plenty of more rain to come for western areas, both on Wednesday and Friday by the look of it.

Figure 1

 

 

Normal service is now resumed

After two consecutive days with Lossiemouth in the number one position as the hottest place in the country, normal service has now been restored as far as temperature is concerned in that part of the world.