St Swithun’s forecast correct in 20 of the last 86 summers

Figure 1 – Courtesy of Twitter

The Met Office have claimed on Twitter (fig 1) that the bit of St Swithun day weather lore nonsense about 40 days of rain has never come true – I beg to differ, and I can prove it using data that is freely downloadable from the Met Office website itself. According to the UKP daily rainfall figures for England and Wales, St Swithun has been proved correct in at least 20 of the last 86 summers. Of course, I am stretching a point to its absolute limit with this assertion, because the UKP series is derived from gridded rainfall data, and I’m counting days with at least 0.01 mm of rainfall, but as you can see (fig 2), the last time it occurred was as recently as 2015, in fact it seems to have occurred fairly regularly in the last twenty years for some reason.

Figure 2

For the purists amongst you who like to define a ‘rain’ day as being a day with at least 0.2 mm of rainfall or more, then the number of wet St Swithun forecasts is drastically reduced, but not to zero. Interestingly, the 15th of July 1931 did herald a spell of 40 days of rain, and here’s a detail graph to prove it (fig 3).

Figure 3

For any of my loyal followers, you may have read a similar blog from me a couple of years ago, but I lost that when I deleted the old WordPress blog in a moment of madness a couple of years ago and thought that I would rewrite it.

Over 2,000 Met Office employees

I was really very surprised to find the other day that the Met Office had over two thousand employees. I found the information in their 2015 Employee Profile, and on the 31st of January 2015 it reported that they had 1,806 full-time and 239 part-time employees on their books, which adds up to 2,045 in total. I say very surprised, because I thought the total was closer to 1,500, but I may have been mixing that up with just the number of people who worked out of their Exeter HQ.

I won’t ask the obvious question, because I’m sure you can probably guess what that is, and because until just over five years ago I was one of ‘two thousand’, but I would have thought that with never-ending automation, and the rundown of our military bases in recent years, that numbers would (or should) have contracted and be closer to one thousand rather than two.

It was also interesting to see that the oldest person working for them was 71 years of age, and that there were 65 people over the age of 60 still working on. By law, I think that they’re required to publish their employee profile and diversity data which is a good thing, I wonder if Google, Microsoft, Amazon are obliged to do a similar thing.

Arctic sea ice on the mend (a bit)


The recent demise in the Arctic sea ice extent reminds me of a story that went around about the death of Mark Twain, which he refuted by saying “The reports of my death are greatly exaggerated”. It didn’t look good in September and October as the graph of the sea ice extent showed how slow the Arctic was creating new sea ice. So I decided to look at the figures from the NSIDC in a bit of a new way. The graph above shows daily anomalies, that is the value on the day, divided by the 1988-2016 long-term average [LTA] for that day of the year, multiplied by a 100 to get a percentage. The graph as you can see had two distinct dips, one in early September just after that early minimum when the anomaly was around 65% of the LTA. The sea ice bounced back very quickly from that minimum and before the end of October was above 76% of the LTA. Those gains were quickly lost though, and by the middle of October the values had dropped to less than 68%. But interestingly, in fits and starts, the sea ice extent has bounced back and is now above the 85% mark. If you look back at summer 2012 just before the summer minimum things were a lot worst than in September with the LTA  less than 55% of the LTA for a few days. Here’s a bit more of a close-up of the last few months.


This method of graphing daily anomalies is very sensitive to any daily changes in the sea ice extent, and I think it’s one of the best ways of keeping an eye on sea ice extent levels both in the Arctic, and the Antarctic, and talking of the Antarctic, here are the latest daily anomalies south of the equator.


The above graph shows very nicely the rise and fall of Antarctic sea ice in recent years. If you remember up until early 2015 Antarctic sea ice had gained a lot of new sea ice. In fact the 2014 season set a new maximum extent of over 20 million square kilometres, but since then things have been going down hill, and since early October of 2016 the sea ice anomalies have been tumbling. At the moment (3 December 2016) the anomaly stands at 84% of the LTA for that day, not a record low by any means, but certainly this season’s melt looks very aggressive, and these daily anomalies are the lowest since early 2011.

Sea ice extent is certainly in crisis, in both the Arctic and the Antarctic, but at least in the Arctic the season seems to be finally getting itself into gear a little.

The media seemed to have now picked up on this autumn’s shenanigans going on in the Arctic, a little bit late, but never mind.

Here is a list of recent articles that I’ve written on the subject, and I think it’s fairly evident that I have a bit of a thing for sea ice.

So you can see when I add a comment to the Met Office blog, and 10 days later it’s still sat there “awaiting moderation”, I do get a bit irked. I’m not sure what’s particularly wrong with it, there are no swear words or personal insults, just a few comments about the slightly arrogant tone of the piece, and how slow off the mark they’ve been (in my opinion). So here is what I said and you can be the judge, because after 10 days I think they binned them – so much for democracy!


Cloud problems again

Courtesy of BBC

The graphics from the BBC weather forecast (10.58 AM) above, show just how quickly out of step the Met Office model can get within just a few hours:

  • The frontal cloud currently flooding northeast across Ireland is much more advanced than in the visible satellite image than it is in the forecast fame for 1100 UTC (underdone).
  • In the Southwest of England, although some low cloud has spread across Dartmoor and southern parts of Cornwall from the English Channel, the rest of the peninsula is having a glorious cloud free morning, although a few bits of cirrus have now started to make an appearance (overdone). I must admit when I first saw this same graphic in the 8.15 AM forecast I thought that we were in for a cloudy old day.
  • The low cloud is more extensive over the Northeast and central belt of Scotland (underdone).

I would say the Met Office have more than a few problems with their new model, especially with low cloud, but to be fair a lot of the general public will never notice these shortcomings, but this old curmudgeon did.  I Personally don’t think the BBC presenters make as much use as they should during the day of visible satellite imagery, NWP data is fine, but when it’s out of step with reality, it’s just plain misleading.


By the way,  the question marks in the top image are there because I’ve never clearly understood what the different shades of shadows are supposed to represent!

Better late than never…

Rather bizarrely the Met Office finally did get round to issuing a fog warning at 1546 UTC this afternoon, even though visibilities had been less than 100 M all day in the areas that the warning was intended for. It seems to me that someone else is reading these missives of mine other than my 23 regular subscribers…


Here for example are today’s observations from Yeovilton. The visibility was no better than 200 M all day and the maximum temperature was only +0.6°C, so for much of the time the fog could have been freezing.03853-yeovilton-united-kingdom-22-m-amsl-51-0-n-2-6-w

These observations from as close as 3 miles away at Exeter airport show how visibilities had been reported by the AWS as 100 M since 0900 UTC in the morning, ironically they improved at 1600 UTC as the warning was finally issued.03844-exeter-airport-united-kingdom-31-m-amsl-50-7-n-3-4-wMeanwhile at Chivenor in North Devon they had also had been reporting fog since 0500 which persisted all day with visibilities 100 M or less for much of that time.


I don’t know what’s going on at these places but surely the aviation bench must have been pushing out TAF’s in the southwest with fog in them and issuing warnings to various authorities, obviously forecasters don’t do much in the way of interacting or looking out the window these days. The fog didn’t need to thicken up I’m afraid, it had been there all day in Devon, Somerset and west Dorset.

The biggest fog patch that you’re ever likely to see!


According to Ben Rich and Holly Green on the BBC TV weather at lunchtime, this big blob over Dorset, Somerset and East Devon is just a fog patch, well you could have fooled me! Here are the latest observations from 1400 UTC, I would suggest if it’s not budged all day, and as it’s now 1500 UTC, it might even thicken up a bit, not that I want to tell you how to do your jobs that is.


How thick does fog have to get before a warning is issued by the Met Office?

We live with a mile and a half of the M5 and at the moment (2.30 PM) we have a visibility of around 100 M. I have been retired for almost 5 years now, and in that time I’ve never seen fog as thick as this persist as it’s done today in Bradninch. I would have thought that the Met Office would have a warning in force this afternoon of fog for drivers on the motorways and roads across East Devon, Dorset and Somerset. But the warnings board on the Met Office website is as you can see completely blank.

So how thick does fog have to get before a warning is issued by the Met Office?

Interesting question, obviously the answer is thicker than 100 M, or they would already have a warning in force to cover a motorway and busy regional airport…


Met Office see a cold start to the winter…

Courtesy of Met Office

I don’t know why I’m getting carried away with the latest news from the Met Office about a cold start to the beginning of winter 2016/17, but I must admit I am a little. It must be the little boy in me that just wants to see the world turn white, at least for a few days or so, preferably over the Christmas holidays. I love the infographic they use in their long-range forecasting it says very little in effect, but apparently because the QBO is in an easterly phase and totally out of phase, this is expected to weaken the westerlies over the North Atlantic and allow blocked conditions to occur more and hence more winds from the north and east. One thing about the Met Office is it knows how to take advantage of social media in all it’s forms, I can just see them getting warmed up down at the Daily Express at this very moment!


Courtesy of the Met Office


A triple warm sector – not something you see everyday!

The boys down at Exeter have really outdone themselves today with the 06Z analysis – a triple warm sector – I kid you not, three distinct warm sectors, embedded one within the other, between Iceland and Norway.


There is no doubt that warmer air aloft – above 4000 feet at least – has spread down from the northwest over northern Scotland since midnight, take a look at this thermograph of hourly temperatures from the AWS on Cairngorm [1237 M].


At least the low cloud cleared from all but parts of Yorkshire today, so yesterday’s forecast was correct after all. We have had seen some thick cirrus (from the frontal system over central France) to the south for most of the day in Devon, but I notice that’s now finally starting to edge away this afternoon.satellite-image-1330-utc-on-fri-25-november-2016

Why isn’t Met Office NWP data free?

The new £20 million building to house the new supercomputer in Exeter

There’s a link on the Met Office site that gives you a menu of available NWP [numerical weather prediction] models that they produce and that you can buy, but try as I might I couldn’t find any indication of what that NWP data might cost you.

Courtesy of the Met Office

My simple question is: why isn’t Met Office NWP data free?

Don’t get me wrong, I don’t think that all model data should be made freely available, but certainly a subset of it should be, much like the Americans do with their Global Forecast System [GFS] model. At the same time they may like to produce a simple desktop and mobile application for the people of this fair land to view that forecast data with, because there are growing band of ‘expert users’ across the country that feel disenfranchised by the way that they are barred from being able to view what is essentially our forecast data.

Yes, I know the Met Office is a Trading Fund and part of the Department for Business, Energy and Industrial Strategy [BEIS] and expected to turn in some kind of profit each year, but with the help of a simple application they could use this free subset of NWP data to showcase what they can provide and actually generate interest and increase sales of more specific detailed forecast data from the other models that they run.

You could argue that we do see the Met Office data across all the time on our TV weather forecasts, and that’s undeniably true, but how do we know it’s the best forecast data that is being used? With that thought in mind, please take a look at the T+120 forecast for midnight (22 November 2016) from each of the three major NWP models in the world, and see how each of them have done with a forecast made 5 days ago on the 17th.

The boys from Exeter didn’t do too well did they? And they were also not too great at nailing storm Angus at T+120 either.  I didn’t cherry pick this particular example, because until an hour ago I didn’t even know I was going to write this article. Why do I use Wetterzentrale to compare NWP forecast charts? Well, they have for many years provided a website where you can examine and compare up to as many as nine different NWP models from around the world, using the same standard map projection for each. The Met Office do publish forecast fax charts out to T+120 which may be subtly different from the raw model output, but I prefer this way of doing it, after all I am comparing model data.

2016-11-22_084205I want our NWP data to be made more freely available for the sake of transparency, because I would like to know just how well our model compares with the American, French, German and European models, but as you can see that’s far from easy to do. Please don’t email with sites that do this with some fancy statistical RMS verification score because I have seen and they don’t help. My kind of verification is of the mark one eyeball – give me an analysis and any number of forecast charts and I’ll pick out the best one. I know all models perform better the higher in the atmosphere that you go, but for me it’s level zero that’s the most important one.

This article started out as another one of my Don Quixote type crusades to right what I see is a wrong – free NWP data for all. But as I wrote it, it developed more into a questioning of why are the Met Office so reluctant to free their model data, and the year on year spiralling cost of the whole thing. But that’s what blogs and blogging is all about I suppose.

If our NWP model consistently outperforms the rest, then I can see how the £97 million cost of the latest Cray XC40 supercomputer, the £20 million for the building that it sits in, and the time and effort put into its development have been fully justified, but at the moment I have my doubts that it does.