The twelve days of Christmas 2016

I’m sure this last Christmas is now a dim and distant memory to most, so I thought that now we’ve reached Epiphany, and not an epiphany, although some of you may well have, it was a chance to look back and reflect about what the twelve days of Christmas mean to a complete weather nerd through each day’s 12 UTC visible satellite image. If you remember it started with a record mild Christmas day in the UK, and then before the New Year plenty of fog in the south and across France, and then of course there was low Axel as it developed and tracked southeast into the continent from Scandinavia, dragging all that cold air behind it as it went.

Figure 1 images courtesy of the UKMO and EUMETSAT

 

Low cloud reluctant to break

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The BBC presenters are still adamant about sunny spells coming through today as the cloud thins and breaks, but apart from in the southeast of England, there is little sign of it happening in this morning’s visible satellite images. The new NWP model that the Met Office have introduced, seems to be a bit too keen to get rid of low cloud, as it did the other day. Peter Gibbs keeps on about the drier air coming in from the continent, and that may be true at the 925 hPa level, but the surface humidities don’t reflect that dryness at the moment. Paradoxically, the central North Sea seems to be where the dry surface air is at the moment, as you can see from this chart of surface relative humidities for 1100 UTC. The stratocumulus sheet with a base of around 3000-4000 feet across the country is very thin by the looks of it, and who knows perhaps this afternoon the cloud will go, we shall see.

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Updated 1315 UTC

I find it fascinating that when Peter Gibbs hands over to Jay Wynne, how the story subtly changes from one of ‘sunny spells today’ to ‘variable cloud this afternoon’, very slick, but they are still using the same graphics, and nowhere like the amount of clear skies indicated by the model, although the clearer slightly convective air has advanced along southern counties.

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Exeter airport – November 2016

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It’s amazing what you can do with a month’s worth of  hourly SYNOPs from OGIMET. Here for example is a full climatological report for last month (November 2016) for Exeter airport. I think I’ve used more or less every scrap of climate data that is locked up in an hourly report, although I must admit that because Exeter returns hourly sunshine and radiation data there is no way to visualise that it in a monthly tabulated report like this, unless you plot the hourly values in a graph.

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Exeter airport – November 2016

I remember when I was a lad having to fill a Metform (it did have a number but I forgot it) in very similar but not as detailed as this, that’s when I was an assistant scientific officer [ASO] with the Met Office at a variety of outstations around the UK. The beauty of a desktop application like this though, is that I can download all the ~7200 hourly observations required for a month, and produce a climate report like this, in just a few seconds from anywhere in the UK. It would probably work for stations from the rest of the world, but because different countries use and abuse the SYNOP format in different ways, it will need a bit of extra tweaking for general overseas use.

What a month November 2016 was at Exeter by the way, storm Angus and a three-day wet spell, and then eight dry days to finish!

The one thing of course the report screen lacks is access to long-term averages, so that anomalies for temperature, rainfall and sunshine can be included. Some of this long-term monthly average data is available for some key stations around the UK, so it may be possible to add this functionality to the application in time. The other thing it does that any self-respecting climatological application can do is produce a variety of charts :

  • Hygrograph
  • Thermograph
  • Barograph
  • Hyetograph
  • Anemograph
  • Sunshine graph (what is the latin like name for this one?)

This application is still a beta, that’s a fancy way of saying that it’s not quite finished, but that’s the problem with the majority of the many weather applications that I write. The report screen is more or less complete and the way I want it and data it displays is correct, but the graphs do need more polishing as you can see:

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Barograph – bug in the date range label

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Sunshine – another bug in the date label !

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Anemograph – what happened to the 30th?

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Hyetograph – finally one that looks right

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Hygrograph – date problems again!

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Thermograph – with more date problems

Low cloud more persistent that the BBC may have thought

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Today’s persistent low cloud over parts of England and Wales – a mix of stratus and stratocumulus – has been a little more persistent than the BBC weather presenters would have us believe – and ultimately what the Met Office NWP model forecast. Despite TV weather presenters Carol Kirkwood, Darren Bett and Chris Fawkes all promising how the low cloud would readily break up over England and Wales, it’s been stubbornly persistent, although there have been some breaks along the south coast and in the far southwest.

Meanwhile, yet again for the bulk of Scotland (apart from the far north), Northern Ireland, Northwest England and the West of Wales it’s been another beautiful day with gorgeous blue skies and another sharp frost tonight.

The BBC are forecasting more or less clear skies across England and Wales for tomorrow – let’s hope they get that right. Apparently the model is forecasting a cloudy weekend, but the way it’s performing at the moment I wouldn’t bank on it!

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Clear and frosty in the north – mild and windy in the south

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High speed stratus at 300 feet over Devonshire early this morning

The minimum temperature last night [18-06] dipped to -8.5°C (16.7°F) at Tulloch Bridge, Inverness-shire, meanwhile temperatures at many places across the south didn’t fall any lower than 10°C, that’s because there’s a fresh to strong E’NE blowing across areas south of 53°N, and a full gale blowing down the English Channel – in the opposite direction to which it was blowing on Sunday and Monday just for a change. I just wonder if there’s some kind of theme already starting to play out for the weather over the coming winter months here?

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Alex Beresford – the ITV Weather presenter – says that it will be breezy over Cornwall today, well spotted Alex.

Scotland – the place to be!

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Webcam image courtesy of Winter Highland (I have a sneaky feeling that the hills in the distance are part of the Nevis range)

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Images courtesy of the Met Office

 

Scotland is once again the place to be at the moment, at least if it’s glorious late Autumn weather and views of snow-capped mountains that you’re after, thanks to high pressure that’s reestablishing itself over the north of the country. As well as snow on the highlands, snow is also clearly visible on the southern uplands and the mountains of the Lake District. Here are the visible satellite images of the UK for the last seven days, and if you take a close look you’ll see that the snow-capped mountains of Scotland have been visible for 6 out of 7 of those days.

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Images courtesy of the Met Office

Of course clear days by day spell cold nights and nights have been quite cold. I’m not privy to the hourly Braemar temperatures which the Met Office keep under lock and key but here is the thermograph for the last 10 days or so from Aboyne just down the road and a little bit warmer.

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Data courtesy of OGIMET

Mostly dry frost and fog from midweek?

According to Tomasz Schafernaker’s headlines in the BBC weather forecast as 12.55 PM, it will turn “Mostly dry with frost and fog” from midweek. Well that may be true for the bulk of the country north of 53°N, but not for the south if the latest GFS forecast is anything to go by. Thursday looks a particularly kind of bleak day in the south, with strong easterly winds and I don’t see the remotest chance of any overnight fog unless it’s of the high velocity type. In fact, it stays rather breezy in the south right through till next weekend if the GFS model is to be believed.  Meanwhile the weather in Scotland once again looks fine and anticyclonic throughout, at least away from the far north.

Who writes these headlines? A much more accurate headline would have been “Fine in the north windy in the south”.

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A little belter

The trough that’s heading into Northwest Wales is a bit of a belter. On the 1100 UTC chart  the pressure at Valley is slightly lower that at Ronaldsway so a circulation is starting to form on the tip of it due to the large pressure falls ahead of it.

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The rainfall has been no less spectacular this morning with some very bright echoes coming into Cardigan Bay. Interestingly, the rain is running well ahead of the surface trough.

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8/9 November 2016 – trough disruption

The trough disruption that occurred yesterday across the British Isles was well forecast by both the GFS and UKMO models, here are a couple of animations in hourly time steps of it happening. The warm air quickly occluded out as it came up against the cold air over Scotland and northern England and a secondary low formed on the triple point as the pressure continued to fall. This low tracked ESE across Wales and southern England with strong winds on its SW flank and behind the cold front.

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Further north snow fell quite widely east of the Pennines even to low levels.

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They’ve finally got the projection right..

Good news! The Met Office has retained the Channel 5 contract to supply the broadcaster with a weather forecasting service. It uses the same Visual Graphics engine that they’ve jointly developed with some other high-flying graphics company and which powers the ITV weather graphics.

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Courtesy of Twitter

Unlike the ITV weather the map projection on the new Channel 5 weather forecast from the Met Office, they seem to be using the right map projection judging from this Twitter image. All Scottish people across the land will feel an immense sense of relief as Scotland now appears the right size instead of being that shrunken bit up at the top.

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Courtesy of the Met Office

Now we’ve only got them to apply the same path to the ITV Visual Graphics system and we’ve done it! Mind you they still need to fix the number of triangles and semi circles that appear on cold and warm fronts to really finish the job. Here’s an example of just how silly this kind of chart looks to anyone irrespective of how much meteorological knowledge they have.

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