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pyrotech

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Posts posted by pyrotech

  1. Brady  pretty much sums things up

    The met office model which we do not see as public, is still showing some Snow Friday into Saturday but becoming rain later, in fact whole South UK in the less cold air before Wednesday, however it is also changing the output on each run. 

    The warm air is initially likely to flow over the colder more dense air but that does two things, one it cools the warm air allowing some precipitation, but also the colder dryer air will start to kill off the precipitation. Some areas could see freezing rain for a time.

    Models certainly going wrong way after initially pushing a classic breakdown back, it now looks like a damp squib with transient snow if lucky for many.

     

    • Like 1
  2. For me its not the low thats the problem, the Azores high ridges to try to join up with the Scandi high. That blocks the jet Stream.

    Without that we may have had a corridor allowing slider lows. So close but no cigar for Far South and West UK.

    Little bit envious of those on the East UK

     

    Then we have possibility that the Scandi high moves South East. I am guilty of relying on the MJO phase to hold the high in position, and eventually travel westwards, but other drivers overcome the lagged effect of MJO, but for how long?

  3. GFS keeps us mainly dry but looks perfect to maintain cold, except it squeezes the Scandinavian high into Greece, that would be goodbye winter hello Spring, however its just another option. I say that because its against the MJO, so it would be a strong push by the low to force that, not impossible but just another of 100s of evolutions. Something we can say we are used to at the moment is models that can not handle the current synoptics.

    • Like 1
  4. Met office Model, shows snow Friday, 3 hours. Then Snow Saturday that becomes Marginal later as heads towards London and decays. Seems cold may be fighting back late Sunday but close call, temps 3 - 5 c on this run late Sunday near M4 belt. It looks like a slow push East that goes nowhere, this is too tight to call .

     

    • Like 1
  5. 22 minutes ago, goosey007 said:

    A good read thanks ....8 degrees for Monday on bbc  dampens my enthusiasm into next week ...

    Its one model run, i can assure you every run Met Office model shows is different just like ECM and GFS, trust me i have just checked.

    However even latest run gives snow Friday and Saturday.

    They are holding back from decisive forecast for the end of the week in general and when mentioned they talk about potential snow and uncertainty.

    Thats what model shows, different timings and extent for potential snow.

    If the forecast for Friday is not decided, what does it say about forecast for Monday?

    It says that current prediction (latest run) is one of many possibilities.

     

    • Like 1
  6. Remember folks

    We have no issues getting Precipitation here in Wales, its cold we struggle to get.

    We have the cold and it will be difficult to move.

    Breakdowns are our best option and Storm Emma was an attempted breakdown.

    Models have hinted at a transient snow followed by rain even, now hinting at extending the cold instead. So we can not only see opportunity extended, but also chance of multiple attempt at failed breakdowns. Nothing is nailed on by ANY model including Met Office hi rez.

    This can still be a very good even where everywhere in UK will have seen significant snow

    Scotland ❋

    East England ✻

    Very good chance that South West and Wales will get it soon ✻

    Central England follows ✽

    Now with that as a fair possibility i would say its better outlook than all of last winter

    Patience Friends

    • Like 6
  7. 27 minutes ago, Allseasons-si said:

    Yes Scott then phase 8/1 for complete retrogression for a northerly afterwards,all roads lead to cold at the moment,lets see if w can get the second bite of the cherry from 192 the a third one later on,seems plausable but don't take my word for it lol

    BTW,i hope that your mother is doing OK mate☺️

    Wow guys really looking ahead, thats next weekend for phase 8 and 24th for effect

    Although phase 6 is Scandinavian blocking 7/8 in Greenland blocking and into phase 1 is Atlantic taking over.

    With the lag effect we do have a fortnight plus of opportunity with Easterly  then most  likely Northerly and if we get that far it can have its phase 1,  i know thats forecast but in all honesty i see phase 8 into COD, but we will see.

     

     

    • Like 1
  8. 5 minutes ago, sheikhy said:

    Is there any support for this kinda scandi high from the mjo and other background signals?!!

    Yes phase 7 on 26th Jan, into phase 6 and now heading into Phase 7 again,  been 12 days since entered phase 7/6 which is right for influence Northern hemisphere. Discussed this few days back, Why models seemed to go with stronger jet due to temp contrast over USA and seemed to ignore effect of MJO. Seems models caught up now. 

    • Thanks 2
  9. Anyone noticed that the model thread has become the South East regional thread.

    Do not talk about West UK whatever you do, get hounded lol

    Weekend looking okay here in Wales but i am not seeing lots of Snow. 

    Wednesday look interesting, but hope the fronts push in and then stall before retreating again.

    I am not a fan of transient snow, so hopefully some ideas by models and indications by Met O, that this could happen does happen.

     

    • Like 7
  10. 10 minutes ago, Scott Ingham said:

    This reflects my own opinion on the likely way forward

    Put simply in this period we have 1 force competing against two.

    In the mild corner (1)- The SPV wants to chuck a lobe of the vortex over America and the atlantic firing up the jet

    In the cold corner (2) We have a stangnant highly amplified signal in phase 7 which eventually moves to phase 8 of the MJO AND we have a spike im AAM due to peak around the 13th of the month.

    Option 1 is flat option 2 encourages further height rises both over Griceland and Scandi.

    All winter the models have showm to underestimate momentum and tropical signals until within 120.

    Its around 168-210 the breakdown is shown to occur.

    If my own logic is correct in two days time friday 12z i expect to see models prolonging the cold and either strong wedges or heights pushing the atlantic energy under prolonging the easterlies or creating battlegrounds in a favourable manner

    A well put post that highlights the conundrum. I agree that MJO is the most likely to overwhelm the SPV, but any ideas why the models have such a poor comprehension regarding this battle. I would suggest MJO influence is not accountable in output and the models are at times reverting to "normal" intensification with out the MJO effect or they believe that the contrast is great enough to displace the blocking MJO would normally build with strength.   

  11. Hi res is showing precipitation to west of Ireland Tuesday turning to snow, 100 miles out to sea. Thats a good indication that anything trying to push in will be readily falling as snow, The Southwest approaches has precipitation the same.

    Can i add, slightly off topic The latest BBC (stav  Danaos) only went as far as Sunday. I compared the graphics and they very much showed the UK Met output. Not ECM.  They will do paid services for forecasts when the weather is potentially disruptive ( i believe). 

    • Like 5
  12. 7 minutes ago, Don said:

    A good post pyrotech.  Do you think it's a case of the favourable MJO vs a strong jet stream courtesy of brutal cold coming out of the USA and seeing which gains the upper hand moving forward?

    Yes i think thats what some of the model runs are showing, but  some runs have a less effect East North Atlantic ( UK) so its intriguing how those models are handling the contrast in air temperature, the resulting jet stream and the low.  I would hope a seasoned forecaster with vast experience like John Holmes would pop in and give his thoughts. (There are quite a few others on here too)  I need to look at 500mb charts to see what is driving the data correctly or incorrectly. 

    There could be some interesting warnings pop up over the weekend  (for next week) if MET output remains same, but that changes like the other models by run to run, especially 5 day plus. Interesting as in where they are !

    • Like 1
    • Thanks 1
  13. My post was about the models and what is shown in Fi

    Its probably the most interesting part of model watching right now, as cold and snow is almost guaranteed for the South East during Saturday - Tuesday.

    Its likely for some snow even imby. Many areas will see some snow and settled snow.

    How much and where exactly is pointless as it will change and cause some disappointment and others will have nice surprise.

    Its fun thou and we all enjoy seeing the possible accumulations mount up, including me.

    However  the real interest now in meteorology is watching the models try to get a grip on the length of the cold spell and the depth of the cold. The battleground can be amazing.  So far, we have seen the cold air retreat and return South 3 times, its really stubborn against the cold dense air. I have never said the cold spell is over, i just posted two charts from 2 main player models with one possible scenario that their operation runs suggest, with then the Ensembles contradicting somewhat, what they show. The UKMO and previous runs have indicated a better solution.  What would be useful on here is some valid analysis on the heights to our North and the effect on Jet stream (including USA storm) and how the models are changing them. The MJO with lag is perfect for a more blocked pattern, for me it must be the contrast in temp  coming from USA that is causing the changes predicted, but are they likely or over cooked.

    Please do not see this as in anyway taking away the snow many of us will see over the next 5 days plus, but if we can look for cold in fi when not in place, surely we can look in fi for signals from the models on what is likely next.  

     

    • Like 5
  14. The cold spell is on but the certainty evaporates around 9th/11th.

    We have two major models now that deepen the low until it is strong enough to affect  the cold air, we also have heights over Greenland diminishing.

    If we look at the ECM and GFS at 11th Jan, There are strong South Westerly winds that will rapidly change any frontal snow back to rain. 

    1112771372_Screenshot2021-02-03at21_18_08.thumb.jpg.63c6162786494040eb1828c100cc52e8.jpg1102500589_Screenshot2021-02-03at21_17_56.thumb.jpg.f0a812243b45265f18aef9c609cb0fe5.jpg

    However, the models are playing with a number of opportunities in that range.

    A Strong jet stream is the main driver, it changes from a North West too South East jet, to becoming a Westerly Jet. This allowed by the forecast loss of heights to the North over Greenland. It is also affected by The high over Scandinavia slipping away but strengthening. Both of these can be more stubborn than predicted.

    Question is how much these scenarios are credible due to that severe cold boundary coming off the East Coast USA.

     

    The Ensembles show a lot of uncertainty on this scenario, i show Cardiff, but they follow similar path in Essex so this is a good example.

    642607522_Screenshot2021-02-03at21_17_02.thumb.jpg.fc00eb91c7dccc8734d18c86b127faa7.jpg

    We have seen that low become less deep and a slider and that could return.

    The breakdown or attempted breakdown may not be something many want to talk about, but for many in South UK and especially those in South West this is very often the route to any meaningful snow. So sorry if this talk about breakdown is not the main talk for those in North Sea Coastal zones.

    Definitely a worry that the two big boys have this scenario, in what is definitely fi ground, but for now i see it as a valid option (disappointing one) as it not only limits the throw of the dice for South West uk, but also shortens the cold spell for those who get the snow.

    The pub run may show the better option again, but i feel it will be at least Saturday before the attempt of breakdown is decided. Many of the twitter accounts from professional are eerily quiet and i think that tells the story. 

     

     

     

    • Like 4
  15. 14 minutes ago, Man Without Beard said:

    Based on all the models I've seen in the past 24 hours, this is my interpretation, well it was a picture or 1000 words 🙂 

    562570822_Forecast7-10Feb.thumb.jpg.25c3f7856c82a31f59ca89f9fea6c98a.jpg

    I have to say, that is quite a good summary of the main potential this next week. All those lines can be adjusted in every direction and some surprises are likely too. i would add that the middle band could change to heavy snow followed by rain, but i am really in hope that does not happen.

    I have a sneaky feeling that this may be a rare occasion where a satellite image shows all areas of mainland UK with a covering of snow. The potential is definitely there.

    • Like 3
  16. Its a well known fact, that here in UK, we need the cold in first. We have no issues generally for precipitation.

    However, in Wales and Southwest England we are in prime position, for breakdown or attempted breakdown scenarios.

    These of course can be all or nothing, but good example is 2018, when Storm Emma crept into South Wales and dumped lots of the whitestuff over us.

    Next week has opportunity for similar conditions

    Embedded cold over UK, slider low pressure nudging into the cold.

    The beg question is will Wednesdays low slip to far South, into France?

    If so i expect the low behind it, to push a little further into UK.

    Perfect conditions are these lows to just nudge in and not go to far North. its currently a viable option.

    If they do push too far North it would be heavy snow followed by sleet / rain.

    Either way next week looks like we will all see some snow and possibly disruptive sustained snow.

    • Like 6
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