Weather Boy

Quite, and that's exactly what is shown on this temperature chart that someone posted earlier. 36°C at Heathrow and, er, 20°C, maybe only 17° on north Essex/ Suffolk coast! Incidentally, meto are saying 34° for southern counties later in week. Baffled as to why BBC persist with 25° maxes. Are they expecting a temperature inversion??!! Still, meto reassuring me I'm not going mad.

Hi Rob I think that there are a couple of flaws here. Firstly, there are at least tentative signs that the part I have bolded may be wrong. Second, happy to be corrected, but it seems to me that on this forum everyone says Greenie high = southward forced jet = washout summer. True, we have seen that before, the classic being 2007. Yet, we have had HP in place in the region (Iceland too) throughout the spring and conditions, certainly in my location have been generally very benign. So I don't think it follows. Thirdly, don't really buy your opening sentence! It's not a lack of articulation, it's a lack of evidence, to my mind! Cheers, WB

For the benefit of newer model watchers. StormChaseUK is making a ridiculous statement. The models are usually pretty sold for maybe a week ahead, and one can look at trends for perhaps two weeks ahead. To suggest that they are worth taking seriously beyond that timeframe is for the birds. Sometimes even within a week there can be doubts, even for the general trend, and contradictions between the models. Some of the more knowledgeable posters on here (see, for example, Tamara's post I think it was yesterday) try to look at long term trends using background signals that are way beyond me. But even they will admit that this is taxing, fraught with difficulty and often wrong. Even these exercises will not normally look much beyond a month, certainly not with any confidence. Seasonal forecasts are extremely difficult and certainly not based upon a few days' of operational model output. So, anyone attempting to make a prediction for an entire season during its opening days based on current model output hasn't a clue (or is, as Danm implied, doing it for their own reasons). They might be right of course, but if they are it will be because the weather happens to tie in with what they said by coincidence, not because they were interpreting the models correctly. I hope this is of benefit to those possibly confused by such comments.

I disagree. I just did a little experiment by tracking the eastern edge with my cursor and my conclusion is that whilst the boundaries are not 100% static, generally it's not budging. Eastern edge is pretty well Oxford, as it was some hours ago. It seems to be merging with the precipitation further east, though, which is moving NW.

Absolutely, Nick. It's not perfect, but I think my answer to his question is correct!

Because they are one of the few location specific ensembles that are freely available (and it's close enough to the UK that it probably doesn't make much odds).

Hopefully a tongue in cheek comment? If not, very unscientific as it literally means that you are allowing your emotions to determine which model output is likely to be correct!

I'm not sure there is ever much point looking at GFS post 144h. Certainly not 240h.

As I understand it, the strength of a block is not indicative as to its stubbornness or otherwise. 1050Mb can be blown away relatively easily, whereas 1028Mb might just not shift.

Ditto, although that is applying the de minimus rule, as we have had a few instances of 0.2 mm. That aside, last rain was early hours of 30 May. If it stays dry today and tomorrow, that will double my previous record! Insane.

Sorry, Gavin, not following you there. The scale below is inches. Most of the country has in the region of 0.2 inches which is 5mm. Am I getting something wrong, or are you?

I'm guessing that's because the snow blows far more readily than rain, so can hit the ground at a different location from where it starts falling from. Maybe,

Is it snowing with you? I am in the City up a big tower and I probably see your location. Currently sun peeping out here, after white out conditions earlier. Looks to me like you don't have the same at present.

My feeling is this is right. Why? Well, blizzards in a snowy breakdown were forecast in 1987 (I think it might have been). Forecast to be midlands or even further north but didn’t get further than Devon. Obviously forecasts are much better now but that was an error in forecasting that night, we are now discussing something 6 days away. Same situation I feel just more days away. Second BBC not really discussing milder weather in forecast for next weekends weather. Not even mentioned as a possibility right now. Third, SSW played havoc with models, looks like second one is doing the same. My current bet is that frontal system gets barely up beyond the channel. Downside for snow lovers if I’m right is no snow from it. In which case just have to be content with 10-20 cm predicted from showers for those of us in the east at least!

January 1987 probably best comparable and I think NW did OK then, did it not? Not sure about February 1991 also.

Maybe not (from your POV), but with HP to the north and LP to the south, and therefore winds from the east bring in any disturbances from that direction, it's hardly surprising.

Can someone explain to me why everyone thinks that the track will be more southerly than currently progged?

Similarly, we are still under snow and ice. I understand go 20 miles odd West and there is nothing. I'd like to know why. Snow fell at both locations but only settled here. Tiny surface temperature variations.

Thank you very much but: A) how, meteorologically is that different from a full High and B) how do you spot it from the charts? Again, offers gratefully received!

John, for the years on this forum I've been puzzled about the difference between 'surface' And, erm, 'real' high for want of a better word and I still don't know. Furthermore, how do you tell the difference from a chart like that? Assistance gratefully received from a bit so newbie....!

Right.... So, today we know that the models are definitely right. Whereas yesterday, when they were showing cold, we may have thought that they were right, but we now know they definitely weren't. That is illogical. There is no reason to think that the models are any more likely to be right today than they were yesterday. You don't need much experience of the models to see that, but it still seems that some are insistent on believing what they want to believe from a particular day's runs. Nobody knows for sure what the weather will be like much after next weekend, including the models.

Thanks, guys, for not lettting me skwak into the ether without any response from anyone! I'll come back to the topic of weather, rather than bank holidays, in a second, but prior to the June election this year, Jeremy Corbyn proposed 4 new bank holidays for the saints day of each patron saint. Fine in principle, I thought, but 3 of them are in the spring, when we have too many bank holidays anyway, and the other is in November, one of the dreariest months of the year (although that one at least does break up the long stretch from August until Christmas). Interesting article, Malcolm. I hadn't actually googled the issue at all. Summarising, it sounds as if we have roughly 1/3 of BH's broadly fine across the country, 1/3 broadly wet, and 1/3 hit and miss, depending on where you are, presumably with the usual scenario that it's most likely to be the NW that gets the bad weather and SE getting the better weather. I don't know how that compares with the weather in May and late August generally. This leads me to the topic I want to explore again soon, which is, based purely on the weather, are the BH's in the right place? I made the observation in my original post that the August BH is far wetter than average. Note also the differential between average August max here and the average for the last week. A fall of 1.85 C, suggesting that the first week of August, where the BH was prior to 1965 when it was moved, saw even more of a differential! I'll post again when I research this further. Finally, the mention of August BH 1986 made me go back to my childhood records, but unfortunately, they started in December 1986, so just missed that.

Hi Created a new topic which might be of interest to those in our region: Please visit and comment. WB

Are Bank Holidays associated with bad weather? Introduction Following the recent hot and sunny bank holiday (“BH”), I wanted to test the widely held belief that BHs are associated with poor weather. Method and Limitations of Work I used my own weather data to test the hypothesis. This has the following limitations: 1. 1. It dates back only 10 years. 2. It is for my location only. h 3. The data may not be as accurate as Meto stations, especially prior to mid-2013 when I upgraded my weather station. This is particularly so for sunshine hours, as these are based on daily estimates. Nevertheless, it should act as at least a guide for the hypothesis for my region of the country (south-east/ East Anglia). I could have used Met Office local data, but it seems better to compare like with like, i.e. my data with my data. I calculated the average for the relevant weeks of each BH, and then calculated the average for each BH for the same years. I only looked at the two May holidays and August, because the winter holidays don’t seem to receive the same attention (as nobody is expecting warm, settled weather in any case) and Easter is difficult due to its variable date. Note that I only looked at the day itself. I did not look at BH weekends as a whole. A further note is that these stats relate to the whole 24 hours, ending late evening. This means that stats could mislead one if, say, one BH had heavy rain the previous night, clearing to a sunny day (although my notes do not suggest that this has often been the case, if at all). Overall, therefore, this is not a very scientific study, but it is a reasonable guide to the issue. Results and Comment Early May Bank Holiday I have not set out all of the data, only the averages: Max (C) Min (C) Rain (mm) per day Sun hrs May generally 18.92 7.95 1.48 5.88 Average 1-7 May 17.3 6.48 1.4 5.65 May BH 17.22 6.99 1.07 6.1 Late May Bank Holiday Max (C) Min (C) Rain (mm) per day Sun hrs May generally 18.92 7.95 1.48 5.88 Average 25-31 May 18.93 9.65 2.43 5.73 May BH 18.93 10.11 2.79 5.11 August Bank Holiday Max (C) Min (C) Rain (mm) per day Sun hrs Aug generally 22.7 12.97 1.9 5.27 Average 25-31 Aug 20.95 12.46 3.73 5.3 Aug BH 20.57 12.46 3.9 6 Conclusion Summary I am no statistician but it seems to me that deviation from average is not significant in any instance. Indeed, in some instances, the exact correlation with average is almost spooky. The following are the slight differences observed: Early May BH Slightly drier and sunnier than average, with slightly higher minima. Rain-wise this BH appears to be less variable than the others and notably drier. Perhaps not surprisingly, the range of temperatures is however variable with maxima varying by 12C and minima a huge 17C (2-15C). There were no sunless days and it was significantly sunnier than the late May holiday despite the days being shorter. Late May BH This also has higher minima (at 0.7C, this is arguably significant) but is also cloudier and wetter than average. As that rainfall is some 24% more than average, one might think that was significant. However, it should be noted that the mean rainfall is hugely skewed by 2017 which received 16 mm of rain. If we eliminate that year, the mean would be only 1.01 per day and thus very significantly drier than average. Therefore, it seems unlikely that this is significant. 2017, along with just one other year, was also sunless, and it is this that makes the BH slightly cloudier than average. Balancing this, 2012 and 2013 were both very sunny (and the former was the warmest). Temperatures are the least variable for this BH, with a maxima range of 10.7C. August BH This has slightly cooler maxima and very slightly wetter but nevertheless sunnier than average (and this latter difference is more significant). Rainfall wise, this was the most variable BH. 2014 and 2015 were two ‘stinkers’ in a row, with zero sun and substantial rainfall of 18 and 16 mm respectively. Apart from those two, there was barely any rain at all. These were the only sunless BHs, but generally, sunshine totals are not impressive. Maxima was also very variable, with 2013 being almost as warm as 2017 but the two ‘stinkers’ mentioned above logging a pathetic 15.7C and 14.1C respectively, the latter being the joint lowest August maximum I have ever recorded. This means that August BH maxima have a range of 13.1C, the highest of the three. Brief Executive Summary There is most likely no notable variation between average weather likely at the times of year and weather experienced over bank holidays. This is not surprising given that the weather does not know or care when England &Wales has its bank holidays. The limited variations that exist are unsurprising and probably not statistically significant. Hence, they vary both ways: some suggest better BH weather, some worse. Whilst not particularly unscientific, I think that when people next complain of BH weather, I shall say that on average it is no different from average for the time of year. Follow Up Work This begs a further question as to whether we have Bank holidays at the right time of year. The average annual rainfall at my location based on my data is a fairly modest 601 mm which equates to almost 1.65 mm per day. The early May BH is below this average but the other two days, and indeed in August, both the week and the BH itself, the figure is almost double that! I propose to take a look at this issue in a follow up and it is for this reason that I have inserted the averages for the entire months in which the BH falls. Meanwhile, it appears to me that more work could be done to investigate this hypothesis using CET and Met Office data over a longer period than the 10 years I have used. I hope that this work provokes some discussion. WB

Rob - that is the six million dollar question with a lot of model watching. Which weather system 'causes' another to be in a particular location. I don't think anyone knows for sure - certainly not me. Disagree with your second para. Weather systems and patterns can and do change at any time of the year, sometimes quite unpredictably. I don't consider that this unsettled spell was modelled at all well until relatively short notice i.e. less than a week. It started in a very low key way and expanded. Who's to say that there might be a similar change to settled at some point, maybe even relatively soon. I totally agree that there is zero signal of that at the moment, but I think it's wrong to make any firm predictions beyond roughly the end of this month. Had I attempted to do so about a fortnight ago, based on model watching, I'd have been suggesting that we would be sweltering round about now! I suppose you are referring to history, but you can't seriously be saying that all or even most Augusts end up exactly the same way as they started, if unsettled?