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  2. And so the train rolls on. Icon 120. Better heights into Greenland.
  3. @DiagonalRedLine constructed an excellent jargon glossary some time ago here: Keep in mind that often terms are used quite loosely. Abbreviations too, are overloaded, e.g. SW can mean south-westerly, south-west, shortwave, stratospheric warming depending on the context.
  4. Whilst Glossea isnt at the moment showing a SSW what it does seem to agree on is weak zonal winds at the start of December Still quite a bit of interest in this for me.
  5. On November 18, the World Climate Service issued its seasonal forecast and discussion for winter (December-February) 2019-2020 in the U.S. and Europe. WCS seasonal outlooks include an overview of expected climate anomalies, key drivers, and risk factors for the upcoming three-month season, and our forecast document contains detailed discussion of available predictors, including dynamical model forecasts and statistical and analog guidance. Analog analysis has long been a staple of the WCS methodology for seasonal forecasting, and we invariably rely on diverse sets of analogs derived from numerous aspects of current global climate patterns. Only on rare occasions do we focus on individual analog years, because the climate phase space is rarely a very good match to any previous year in the modern history in more than a few respects; there are nearly always significant differences from any candidate analog year. Moreover, the degrees of freedom in the climate system are too numerous to expect a close correspondence with any past year to continue into the future, and so any search for “the perfect analog” is a fool’s errand (even if the climate were assumed to be unchanging). Nevertheless, the latest WCS seasonal forecast report discusses a very notable confluence of similarities between the present climate and that of winter 2002-2003. In keeping with usual practice, the WCS winter forecast is not unduly influenced by the 2002-03 analog, but the degree of similarity is so striking that it is worth considering the 2002-03 outcome as a plausible outcome and risk scenario for winter 2019-20. The following list of similarities was presented in the forecast document and is reproduced here: 2002 is the top QBO analog year, based on the 12-month evolution of the 30mb QBO index The Indian Ocean Dipole was strongly positive in September and October 2002, and tropical convective patterns were similar; 2002 is the third best analog year for 200mb equatorial velocity potential A region of highly anomalous warmth developed in the northeastern Pacific in late summer 2002 and persisted through autumn, similar to 2019 Arctic sea ice was low in summer 2002 and set a record at the time for low September ice extent The October Northern Hemisphere circulation was similar in 2002, with Arctic blocking, a trough over northwestern Europe, and a very similar ridge-trough pattern over western North America. The November MSLP pattern was also similar with respect to high pressure north of Scandinavia, low pressure near the British Isles, and low pressure south of the Aleutians. October 2002 had the highest snow cover on record (1967-present) over North America; October 2019 was the third highest The 10mb polar vortex was much stronger than usual in the first half of November 2002, but the Arctic Oscillation was negative for November, similar to this year. No other year provides such a close match to this unusual combination, although 2018 is also a good analog. Remarkably, 2002 is nearly a perfect match to 2019 (better than any other year since 1900) for Central England Temperature in August, September, and October. Perhaps coincidentally, October 2002 England & Wales precipitation was also nearly identical to 2019, and November was also extremely wet (October-December 2002 was the third wettest such period on record). 2002 and 2019 are the only years on record with a strong Southern Hemisphere SSW (Sudden Stratospheric Warming) event; both of these occurred in late austral winter and led to Southern Hemisphere blocking in both October and November. The most significant difference between 2002 and 2019 is that 2002 had more warmth in the eastern equatorial Pacific and much less in the West Pacific; El Niño was more classical (East Pacific) rather than Modoki-like. There was also much less anomalous warmth in the subtropical and northern North Pacific in 2002. In view of the extensive and remarkable similarities betweeen 2002 and 2019, it is tempting to conclude that winter 2019-2020 will be closely analogous to 2002-2003, with a strongly blocked pattern, unusual cold in the eastern two-thirds of Europe and the eastern United States, and reduced precipitation and wind in central and northern Europe (see below). However, as noted above, the WCS approach is to treat individual analog years with caution, regardless of how impressive the similarities appear to be. The combined consensus of a large array of dynamical and statistical predictors is a more reliable guide to likely seasonal patterns, and the WCS forecast is constructed accordingly, but the winter of 2002-2003 should be regarded as a plausible alternative scenario. Climate Pattern Similarities Between 2002 and 2019 | World Climate Service WP.WORLDCLIMATESERVICE.COM Discussion of similarities between late autumn conditions in 2002 and 2019
  6. Hi Griff, welcome to netweather, fellow south Oxfordshire resident! So, retrogression is relating to high pressure blocks - usually weather moves west to east, dictated by the jet stream, but retrogression is the movement of weather systems in the opposite direction, most significant on here is a high pressure block over Scandinavia moving west towards Greenland in the winter. Phasing is two areas of low pressure merging and becoming one. Ridging is the building of an area of high pressure. And short-waves, these are basically small areas of low pressure that mess up what we think will happen! Air circulates round a high clockwise, and a low counter clockwise, so if we think we've got an idea about this on a larger scale dictated by high pressure, a short-wave low pressure cropping up can change the picture altogether.
  7. Let's hope it delivers. Very mild today at 9c. A north easterly wind would be quite unusual for us?
  8. Category 6 - ASCOT, HAYDOCK, NAVAN TRIXIE. LEG 1: ITV RACES STAYER'S HANDICAP HURDLE (Haydock Sat.) - Selection - Eight And Bob LEG 2: HURST PARK HANDICAP CHASE (Ascot Sat.) - Selection - The Last Day LEG 3: TROYTOWN HANDICAP CHASE (Navan Sun.) - Selection - Ravenhill STAKE - 3 x 25p EACH WAY Doubles, 25p EACH WAY Treble.
  9. Listed below, are ANTONYBR7's predictions for Matchday 5: Tuesday 26th November Galatasaray (0-0) Club Brugge Lokomotiv Moscow (0-0) Bayer Leverkusen Atalanta (2-0) Dinamo Zagreb Crvena Zvezda (1-1) Bayern Munich Juventus (3-1) Atletico Madrid (Match of the Night). Manchester City (4-0) Shakhtar Donetsk Real Madrid (2-2) Paris Saint-Germain Tottenham Hotspur (3-0) Olympiakos FC Wednesday 27th November Valencia (2-2) Chelsea Zenit St. Petersburg (0-0) Lyon Barcelona (2-1) Borussia Dortmund Genk (1-1) Red Bull Salzburg Lille (1-2) Ajax Liverpool (3-0) Napoli RB Leipzig (2-0) Benfica (Match of the Night). Slavia Prague (0-1) Inter Milan Regards, Tom.
  10. Well it was, Pete, I'm less convinced it is now for the UK. More recently it seems to me to have been the case that the kind of major atmospheric upheaval caused by a SSW does seem increasingly to be a prerequisite for snowy weather in the south of the UK.
  11. December 2010 wasn't related to a SSW either.
  12. Lowest it got here overnight was 4.7 C , currently 6.3 C and cloudy
  13. And it's certainly possible to get spells of cold, snowy weather without an SSW: 1968-69 had several (five or six?) such periods between November and March...They cannot all have been SSW-related.
  14. Today
  15. Hi all, Long time lurker (well since 2018) but first time posting. Fascinated by how the next few months play-out, especially considering the long range winter forecasts vs recent model runs. I feel like I've learnt so much already but continue to be baffled on a daily if not hourly basis. Would love to understand the following terms in no particular order... retrogression, phasing, ridging and short-wave. Thanks, Griff.
  16. Listed below, are TOMSE12's predictions for Matchday 5: Tuesday 26th November Galatasaray (1-0) Club Brugge Lokomotiv Moscow (0-0) Bayer Leverkusen Atalanta (1-0) Dinamo Zagreb Crvena Zvezda (0-1) Bayern Munich Juventus (2-1) Atletico Madrid Manchester City (3-0) Shakhtar Donetsk Real Madrid (2-2) Paris Saint-Germain Tottenham Hotspur (2-0) Olympiakos FC (Match of the Night). Wednesday 27th November Valencia (2-1) Chelsea Zenit St. Petersburg (1-1) Lyon Barcelona (2-1) Borussia Dortmund Genk (0-0) Red Bull Salzburg Lille (1-2) Ajax Liverpool (3-1) Napoli (Match of the Night). RB Leipzig (2-0) Benfica Slavia Prague (0-0) Inter Milan Regards, Tom.
  17. I believe it is possible to have two SSW events during the winter, this link might help, suggests this happened in 98,99 https://www.earth-syst-sci-data.net/9/63/2017/essd-9-63-2017.pdf Looking at the trop model output this morning, it may even be that this warming event, if it happens, goes alongside a shift to a cold blocking pattern anyway. Speculation of course, but interesting times.
  18. Day 8 from the ECM, GEM and GEF. All decent but the ECM looks best with regards heights towards Greenland and a really good chance of a potent Northerly. I’ve stayed pretty confident of a cold end to the month over the last week or so so today’s switch towards that has been nice, will we keep the trend, lose it, or open the Arctic doors on the 12z I wonder. Fingers are crossed.
  19. to add to this all models do have this greenland area with promise of heights. and as you rightly say the pv is on the ropes with ongoing wave attacks. this morning both gfs models backed of from a strat event not completely. one run later its strengthened i've had a look at nasa model the jma and nav gem on the strat side of modeling all theses have not strat event but then they don't go out as far as the more main models. now there is however warming going on not substantial but more in the form of wave breaking which is nice to see. i've been strongly onside of the wedge into southern greenland. possible that these heights may increase further and that neg nao and ao could well plummet into december. especially if we get a warming event in the strat.
  20. 'Catastrophic' fire alert in two Australian states WWW.BBC.COM The warnings for South Australia and Victoria come as massive fires ravage other parts of the nation. South Australia was very hot today but there were no serious bushfires and a cool change has now gone through. There were ten November heat records in South Australia but Adelaide's 41.6 wasn't one of them ( it was 1.4c short of the November record but 16c above average) and the state maximum was 46.6c at Nullarbor ( 20 above average ) near the coast, in the western part of South Australia. This was just 1.5c short of the state record for November. Thursday will be hot and windy in Victoria and Tasmania. Temperature records far less likely. The catastrophic alert for Victoria is just for northern districts. Nullarbor's readings were pretty impressive today. I have never seen a 1% relative humidity reading before. Nullarbor also started the day at 13c minimum - a massive 33c diurnal temperature range.
  21. Afternoon Got some Ecmwf,Gem and Gfs snapshots below.. Ecmwf.. 22nd.. 23rd.. 25th.. 27th.. 30th.. Gem.. 23rd.. 25th.. 27th.. 29th.. 30th.. GFS.. 23rd.. 25th.. 27th.. 29th.. 30th.. A slow transition to more unsettled conditions they all agree on the overall pattern around the UK with higher pressure continuing to influence close to Greenland forcing the jet south with low pressure systems being the main driver of our weather which means frequent spells of rain with sunshine and showers in quiter interludes with temperatures higher than recently although colder air is never too far away especially by day 10 though that is too far out to have too much confidence yet.. there are some rather interesting very wintry scenarios being churned out by the GFS model past day 10 but shouldn't be taken seriously at all at this stage but fun to look at I'm sure. Will use Gfs for a little more detail.. Rain for the far west today elsewhere dry this is the case for tonight too the rain will push westwards into tomorrow morning but then by tomorrow afternoon and evening it finally starts to push northeast through much of the country but mainly showery bursts of rain nothing particularly heavy indicated atm apart from the far west of the UK.. Thursday morning and evening.. Friday showery areas of rain push northwards but some dry spells too particularly for the far East temperatures milder than recently. Then a more organised area of rain courtesy of the low pressure system responsible for the weather front today pushes North into most of England and Wales during Saturday this heavier more widely winds turn to the east as this low pressure system pushes north most parts perhaps wet until evening. Friday afternoon and Saturday afternoon.. Sunday is looking mostly dry though atm apart from some patchy rain for Scotland but even here not that wet with drier spells. Monday looking much more unsettled once again as more bands of rain push across the country as low pressure moves into the west.. winds are now blowing from the west at this point with quite windy conditions too. Monday 25th midday.. A ridge of higher pressure for the UK in between rain bearing systems for Tuesday means atm it's mostly dry with some sunshine. Tuesday 26th midday.. But by tuesday night the next frontal system pushes swiftly across the country giving a wet start to Wednesday morning.. Wednesday 27th.. Then beyond that the Gfs continues the unsettled theme with more rain and perhaps strong winds too at times but there will be drier and sunnier weather in between.. Staying fairly mild particularly for the south until day 10 when the Gfs then shows colder northerly winds beginning to effect the country but this is subject to change. GFS rainfall totals for the next 10 day's..Wettest for Western areas. Gem rainfall totals for the next 10 day's.. Similar to the Gfs.. Finally the Gem and Gfs ensembles.. Gem ensembles show a milder trend for a time turning unsettled too by next week plenty of rainfall.. The upper air temperature differential during the latter stages of the updates are very big some very mild ensembles but also a few pretty cold ones which seem to cancel each other out enough for the mean to be around average.. That red ensemble member really wants to raise the upper air temperature nearly off the Chart! GFS ensembles not too dissimilar.. The operational Gfs has very big rainfall spikes at the end of the period this is associated with some significant snow in places too but as you can see not well supported as you would expect that far out.
  22. It's all looking very interesting towards month end wrt to a pattern change. Suggestions of a northerly have been showing up on a few runs. I thought maybe a short lived one at first as the trop. vortex moved across towards Siberia with Atlantic ridging moving in after. Now though with continuing wave attacks on the vortex from both sides we are seeing a building trend for Greenland blocking later on. This along with the Siberian placement of the pv promises a greater chance of a more notable cold outbreak. Some interesting outputs coming out now that's for sure.
  23. Strange one this. Didnt Stevenage investigate this interviewed the witnesses and found now case to answer?. I expect the FA have further evidence otherwise this does seem odd. Also do we know in what way he ment what he said?
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