Calvi and the sea breeze

Figure 1

It’s been an interesting week at Calvi in northwest Corsica weather wise. In the heatwave that’s been going on in that part of the world, there’s been a constant battle going on between the sea breeze from the north, and the foehn wind from over the mountains to the south (fig 3). The effect of the sea breezes arrival must be very noticeable at times, and must come as a welcome relief to the town (fig 1). It looks like the flip-flop between the two can happen at anytime of the day judging by the plot grid (fig 2), and the land breeze – sea breeze, must obviously be very finely balanced. Yesterday evening for example, the sea breeze which had set in earlier was quickly replaced by a land breeze that kicked in at 22 UTC and increasing the temperature from 26.3 to 31.6°C. The land breeze then failed early this morning at 02 UTC, and the temperature dropped again from 32.5 to 27.8°C, eventually the land breeze set back in at 10 UTC this morning as daytime heating cancelled out the sea breeze. I have marked out some other sharp fluctuations in the plot grid (fig 2).

Figure 2

The observing station at Calvi is located at the airport, in a valley a few kilometres to the southeast of the town itself (fig 3), with the Mediterranean sea to the north, and ringed by high ground to the south, east and west (fig 3).

Figure 3 – Courtesy of Google Maps

Baking hot

The baking hot weather over southern Europe continues for another day with little sign in the short-term of any relief, here are the 12 UTC temperatures for that part of the world (fig 1), and as you can see that there are a number of stations already reporting 40°C or higher on it.

Figure 1

Alghero in Sardinia is one of the hottest places on the chart, with a temperature of 41°C at 12 UTC. This is a coastal site but these observations are from the airport which is a short distance inland, here are the temperature stats for Alghero for the last month (fig 2).

Figure 2

So today makes five days in a row that the temperature has exceeded 40°C. Here are this week’s plotted 3 hourly observations for Alghero (fig 3).

Figure 3

You would have thought than a 12 knot wind from 200° would have brought a cooling sea breeze into that part of Sardinia and cooled things down at the airport (fig 4), but of course there is very little in the way of gradient over the Mediterranean, so I suppose the low-level flow could be from more of an easterly point.

Figure 4 – Courtesy of Google

It’s not till this time next week before the hot air looks like it loses its grip in that part of the world, according to the GFS model (fig 5), and this hot weather will only exacerbate the severe and very serious drought conditions that are affecting a large part of Italy at the moment.

Figure 5

 

 

Tropical Heatwave continues

Figure 1

The heatwave continued yesterday over much of central and eastern Europe, and was particularly intense over parts of SE France, Italy and the Balkans, with temperatures in excess of 40°C in places (fig 1). In the above chart of maximum temperatures for yesterday the temperature at Alghero in Sardinia reached 41.9°C. Yesterdays overnight minimum at Capo Caccia never fell below 30.4°C (fig 2).

Figure 2

I didn’t quite believe this one, because of course Capo Caccia is a cape that’s stuck out in the sea, but on closer scrutiny it does seem to agrees well with the hourly temperatures (fig 3). The station is at 204 M, so it’s not exactly on the beach, and may well explain why it stayed so warm overnight. Then it all came back to me that I’ve actually been to Capo Caccia, because at the bottom of a series of concrete stairs built into the cliff face, is a series of sea caves called Neptune’s Grotto, that my wife and I visited on our first holiday abroad in 1985, over 30 years ago!

Figure 3

Here’s a picture of Capo Caccia with its lighthouse that I never thought to capture in a picture back in 1985, perhaps because Kodachrome 25 was very expensive back then (fig 4). All I can imagine is that somewhere on the site is an AWS, it’s very similar to Berry Head in Devon, but a lot more dramatic.

Figure 4 – Courtesy of an unknown Italian drone pilot

The poor old southeast

Figure 1

It’s not often that you can say this, but the poor old southeast didn’t score very high on yesterday’s (24 July) summer index. It was cloudy and cool in the moderate northerly airstream, I’m sure that there’s a much better chance of the cloud clearing today. I thought that Exeter might be the sunniest place in the UK (fig 2 & 4), but the time of year and the 23.5° inclination of the Earth put paid to that, and Edinburgh, with 15.3 hours took the honours.

Figure 2

As regards highest temperature, again I thought Devon might have topped that table, but Hurn in Dorset, with a late burst of 6.6 hours of sunshine in the afternoon took that accolade with 24.5°C (fig 3). I reckon it’s about time that the Met Office put an AWS in mid-Devon, because in yesterdays northerly flow down from off Exmoor, gave Bradninch a maximum of 25.9°C, which although a bit on the high side, are seldom reflected in temperatures from Exeter airport just 10 km to the south.

Figure 3

Figure 4

 

Izaña Observatory – Tenerife

Figure 1 – Observatory Izaña – Tenerife – Courtesy of Wikipedia

Izaña Observatory is a great place to watch the stars at night from, it sits at 2,390 metres (7,841 feet) above sea level in Izaña in Tenerife, just below Mount Teide on the Canary Islands. Mount Teide is of course a quiescent volcano, and is significantly higher than the observatory  at 3,718 metres (12,198 feet) making it the highest point in Spain, and the highest point above sea level of all the islands in the Atlantic. As well as being a very important observatory, it also has an AWS that reports hourly SYNOPs, with some very interesting observations throughout the year.

Because for a lot of the time the observatory sits above any inversion and any low cloud, humidities can get pretty low, in fact they are the lowest relative humidities I’ve ever seen from any station, as low as 1% at 04 UTC on the 30th of June this summer for instance (fig 2).

Figure 2

The observatories AWS is fully accessible over the internet so you can watch the weather at the observatory from anywhere in the world.

-80°C at Concordia Station

The summer solstice apparently occurred at 0424 UTC this morning, and of course ushers in the first day of summer in the northern hemisphere, which is a shame because the current heatwave is due to end tomorrow, so we’d better make the most of today.

With all this talk of hot weather, I thought that I’d have a scout round and find the coldest place in the world at the moment, and that of course is in Antarctica, at the Concordia research station to be precise, which sits 3,233 metres up on top of the Antarctic plateau. The temperature there at the moment (06 UTC on the 21st of June) is -80.1°C (-112°F), which is considerably colder than the -68.5°C at Vostok. I never realised that the Concordia research station existed till I found it listed in the SYNOP reports, and it wasn’t till I read the Wiki article about the French-Italian run concern that opened in 2005 did I realise that in sat right in the middle of a disputed area, apparently Australia hold claim to all that ice, the ridiculousness of this situation nicely sums up the stupidity of man in a nutshell. Below is the thermograph trace from Concordia for the last three months (fig 1). Let’s hope that they’re main purpose there isn’t to drill through the ice cap and release some alien life form like in the film ‘The Thing‘.

Figure 1

 

6 June 2017 – wind

Figure 1

This is a chart of highest gusts from 20 UTC on the 5th to 18 UTC on the 6th (fig 1). The highest mean wind speeds were along the open water of the English Channel, where a westerly gale force 8 or 9 blew for much of the day, in fact it briefly made storm force 10 for a time, at the light vessels F3 and Sandettie, in the Straits of Dover. The highest gust in the table was 65 knots (75 mph) from the F3 light vessel. Inland on low ground, gusts were typically in the range 35 to 45 knots. I understand that there were gusts higher than this today on the hills, probably from High Bradfield in South Yorkshire (~1295 feet amsl), the observations from which the Met Office like to keep to themselves, probably I think because the site is owned and run by Sheffield University.

Rainfall still flirting with southeast

The bulk of the heavier rain is still west of London and flirting with the far southeast again like it did yesterday. The main rainfall band is sprawled across central southern England and towards Lincolnshire, where it’s a thoroughly wet and miserable day with some heavier rain now starting to show its hand (fig 1).

Figure 1

Estimates from the weather radar indicate that Portland was the wettest station from 06 UTC with 20.8 mm, and by the looks of this mornings totals from the SYNOPs I wasn’t far out (fig 2).

Figure 2

I thought that the Met Office had now fixed the ‘spiking’ that they got from the Chenies radar (fig 1), but it looks like the tall trees there are still causing problems. Using the position of each of the six spokes that radiate west from the radar site, you could probably map the position of each of the offending trees. After extensive digging on the Internet I couldn’t locate any of the information regarding the tree’s at Chenies that I used in an article a couple of years ago, but this image from the lane that runs past the site gives you a better picture of the problem courtesy of Google street view (fig 3).

Figure 3 – Courtesy of Google Street View

In the aerial view I can now see why the tree’s are such a problem for the Met Office and how they affect the radar signal when they are in leaf (fig 4), and by means of the same image I can also see why they’ll never be removed. The problem lies in a large ‘stately’ home which lies almost due west of the radar. By the look of it is the original house that RAF Chenies was first built around in the 1930’s, and may have served as the admin offices and quarters for officers, but apart from the radar tower, a large aerial and a few other buildings associated with the 1950’s listening post, the rest of the RAF station has been demolished. The house remains though, and sits in a prime location in an isolated spot in the Chilterns, looking very well maintained and very expensive (fig 4). Interestingly, it’s the only time when I’ve ever used street view that I’ve found that I can’t drag the marker to where I can gain a view of this house. Try it yourself, drop the little man and it will take you back to the gates of the radar site. Be warned each time you do it a little red light will flash at Google HQ and all your personal details will be entered into a report at GCHQ. Maybe I’ve stumbled on Theresa May’s house and I don’t mean Chequers? It’s amazing what you can learn in an article ostensibly about weather radar in my blog.

 

Mount Batten dry spell ends

The dry spell at Plymouth Mountbatten has come to an abrupt end overnight, but I’m sure that the rain will have come as a welcome relief to farmers and growers, as well as to all gardeners (fig 1).

Figure 1

I’ve driven by but never visited Plymouth in the 14 years that we’ve been down here, so I hadn’t realised the exact location of the weather station at Mount Batten or the lie of the land (fig 2). I now realise why the can be a lot warmer than you would think in a summer southeasterly, and the wind would be have to be west of south before you got the full effect of the cooling from any sea breeze.

Figure 2 – Courtesy of Google Maps

April 2017 – Weather World

Figure 1 – Courtesy of Armagh Observatory

I’ve just watched another interesting installment of Weather World on the BBC and noticed from the credits that it was written by Nick Miller. He and Sarah Keith-Lucas hosted the proceedings that were centred at a number of locations in Northern Ireland:

  • Belfast International Airport – Aldergrove to you and me, and saw why weather is so important for aviation at airports.
  • Ulster Aviation Society Museum – where they looked at the history of ‘weather flights’ across the Atlantic.
  • Armagh Observatory – and saw how observations are made today, and at their long running climate recordings, which started on the 27th of December 1794.

I’ve changed some sunshine cards in my time at a number of stations across the UK, some of the locations that the recorder was sited were far from ideal, but the observatory at Armagh as a novel approach to getting around the problems of trees getting in the way, the sunshine recorder sits in a lift like device that raises and lowers the old Campbell-Stokes sunshine recorder what looks like 50 foot into the air (fig 1), I hope after that platform doesn’t affect the wind speeds that they measure from the anemometer up there though. They take their weather observations very seriously at Armagh!

At a 24 hour station you could always change the sunshine card late in the evening, it seems strange to see it being changed at 09 UTC in the morning, there were times that someone forgot to change the card, or on very wet days the card almost disintegrated because it was so wet.  Seagulls also liked to attack the cards for some reason, and then there was the perilous job of checking the previous shift’s sunshine card, was that a continuous burn or not, and just when did you start or stop measuring the trace at sunrise and sunset?

I like Sean Kelly the weather observer at Armagh, he’s been doing the job for the last 18 years, and seems to have the right attitude to technology, they’ve tried automatic weather stations in the past, but found that they weren’t reliable enough. That’s what we said in the Met Office for over 30 years, we had a good run for our money but in the end we were replaced by an AWS, try getting a job as a weather observer at the Jobcentre now, Sean might well be one of the last one of us left here in the UK. Nick explained about how observations are taken each morning at 9 o’clock, “this weather ritual that has been happening for over 200 years” he said, except for last Tuesday when it looks like they had a day off (fig 2).

Figure 2 – Courtesy of the BBC

Given the brief from the producer, and the time constraints of the program, Nick Miller did a pretty good job in getting his story across, Sarah Keith-Lucas came across as a really nice person that I’m sure she is. Interestingly they kept it to just the two of them, and wisely in my opinion, didn’t include any input from the ubiquitous Carol Kirkwood. It’s possible that the BBC have decided to use Nick Miller for these kind of programs in favour of John Hammond from now on, and maybe that’s the reason why he decided to take an early shower.