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Showing content with the highest reputation on 20/01/16 in all areas

  1. Oh dear more winters over posts, and no chance of snow, that's it... exactly where we were at the end of the year, and look how things changed 2 weeks on.. I rarely look in this thread.. and I will continue to do so.. its the same in the summer, washout etc etc no sun no warmth... this is a depressing thread to read at anytime of the year.
    9 points
  2. Thanks to @lorenzo, he just reminded me of the NASA GEOS5 model. Looks cool, with the nice seen region where the warming is charging from (the positive vertical velocity). We can also see some of the gravity waves. and regarding the u-wind, its is close to ECM. And also by the wave 1 strength. height wise, its going for a strong wave 1.
    9 points
  3. Not quite fishing , but a decent heads up, it thought about it on the zonal wind plot last night, this moves things into 'ramp' stages. 30mb on tonight's GFS sees a split over this period also with the vortex pegged to Siberia. Bit of a change in the last 48 hrs... Looking at the extent of that and the question of instant and lagged responses -very difficult to second guess things, looks to me though that this impacts right across the column and we are in for a quick hit.
    9 points
  4. Some encouraging posts and signs we may be about to see the polar vortex hit considerably over the latter part of this month, setting up a different northern hemispheric background as we enter February, one far more conducive to producing a colder outlook and more importantly also perhaps a drier more blocked set up. So whilst the immediate outlook looks less than inspiring for anyone who likes cold settled weather, in the background significant building blocks could be emerging towards a very different set up come next month.
    5 points
  5. Latest from the woodshed for the beginning of Feb
    5 points
  6. Not particularly for last year - but we were recently discussing on twitter the importance of the Kara high for AO and NAO blocking events especially when combined with SSW's. Low heights in this region combined with no SSW gave the worst AO/NAO outlook and a strong Kara high combined with an SSW gave a great -ve NAO. The hard work was yet again supplied by the brilliant Ant Masiello. If you go to the tweet chains then you can see a comparison of the years
    5 points
  7. Karyo Do you only make posts in this thread with a negative tone?
    5 points
  8. I must admit I've enjoyed the past couple of days , a good sharp frost,and bright sunny days, makes you feel better in yourself. How anyone can say that they prefer Atlantic driven mild crap is totally beyond me. It's about as much use to anyone as a marzipan crowbar
    4 points
  9. Yes, Tomas forecast looks a bit more relevant now. I actually thought it was a very good presentation and he explained his logic perfectly. Shame it wasn't more appreciated on these forums as the message was badly misrepresented.
    4 points
  10. America is a huge continent so there is always going to a massive snowstorm somewhere on most days during winter.
    4 points
  11. The ECM output for yesterday certainly shows the effects over the next 10 days of the top warming gradually downwelling slowing the mean zonal wind speeds. added to the warming at the trop. level,a real squeeze being put on that cold mid-level.It's the closest i have seen the forecast to a total reversal. To my untrained eye we should see a switch to a -AO quite soon into February if those zonal wind forecasts verify.Maybe a vortex displacement rather than a split at this stage?
    3 points
  12. It only goes out to the 5th of feb so i have no idea what you mean here
    3 points
  13. Also remembering the research that was linked last winter - to have strongest heights centred over the Taymyr peninsula but most important that those heights extend through all layers of the atmosphere. 100mb 50mb
    3 points
  14. the noaa's look, to me, like they support high pressure close to our south/southeast... the mean upper flow remains broadly southwestherly . an early taste of spring is in the offing... with chances of a cold evolution receding . is winter over? not with any certainty but the chances of a decent cold snowy spell must be taking a dive now .
    3 points
  15. February 2009 also delivered deep snow and very low temps with a minimum of -18.4c recorded at Aviemore, I think even London had around 8 inches of snow and some areas more than double that.
    2 points
  16. Just a poll from Florida and this really does some up TrumpMania Florida poll: Trump 48%!!, Cruz 16%, Rubio 11%, Bush 10% And Everyone knows in terms of winning the elections Florida is a crucial swing state In general election matchups, Trump leads Clinton 47.1 to 44.3. Clinton is essentially tied with Rubio, and narrowly trails Bush 45 percent to 42 percent. http://www.tampabay.com/blogs/the-buzz-florida-politics/fla-poll-trump-48-cruz-16-rubio-11-bush-10/2261994
    2 points
  17. 3 years out of......23 years. That's all I went back to, I didn't even bother to look beyond this and you could argue, you could add 2006 into the equation. They are recent examples. That's all I have done.
    2 points
  18. Hey? Based on what? Certainly not historically. 1993, 2004, 2005?
    2 points
  19. Nope but it managed to boost his popularity in America more, So trump was the winner
    2 points
  20. 2 weeks will only take into the opening days of Feb, would you really write off the rest of winter based on what happens over the next 2 weeks? Feb can be a very wintry month but no guarantee of course... We shall see, 20 year anniversary coming up of the epic Feb 1996 blizzard, repeat to mark the occasion please Lets hope charts like these continue to be churned out and gather cross model support into the reliable time frame (if you want wintry weather of course)... GFS GEM
    2 points
  21. You might want to ask some of your Islamic friends that they might know.
    2 points
  22. 2 points
  23. UK Outlook for Thursday 4 Feb 2016 to Thursday 18 Feb 2016: The first weekend of February is expected to herald a move to slightly colder conditions as a north to south split forms across the country. Northern areas are forecast to remain wet and windy, with further gales and hill snow possible in the northwest. Southern parts should stay drier, with lighter winds. Temperatures through most of the period are likely to remain close to or slightly above average, but may fall just below normal by the middle of next month. http://www.metoffice.gov.uk/public/weather/forecast
    2 points
  24. absolutely agree that we could get wintry weather into march. but i think most cold fans here are looking for a decent dumping of snow, and thats unlikely into march. the direction the models are going suggests a shift away from a possible cold evolution - and cold evolutions (or any) dont usually pop out of nowhere but can be seen evolving as the synoptic pattern gets into a favourable position. tbh, unless something pops up in the next 2 weeks (and it could do) then its unlikely that we will be getting any more snow this season.
    2 points
  25. Just under 6 weeks of winter left so plenty of time for change, and if we're really desperate we can string it out to the 21st of March until the end of the astronomical winter!! Thankfully the weather doesn't care what season it is & wintry weather potential doesn't just stop once February is over and the risk of wintry weather extends well into the start of spring. But cold & snow in March aren't everyone's cup of tea, it takes something exceptional to get ice days in March and the stronger sun means more snow melt by day.
    2 points
  26. The direction of travel is clear there but 60N 10hpa still has positive winds of 25m/s at day 10. We had some very positive strat charts last winter from ECM op output which never verified at all. However, with decent ncep support, it seems all is not too well with this leviathan of a strat vortex and the current roar (loud though it is) is likely it's last noisy one this season.
    2 points
  27. I am puzzled by your comment! You have obviously cherry picked the 'negative' comments. It was only last week when I was the first to comment on the 12z showing a major warming. There are plenty of comments here when things are looking promising but then it goes quiet when the warming doesn't materialise to the extent that it was showing before which may lead to inexperienced members thinking that it is still due to happen. For example, many people in the models output discussion thread are basing their hopes in the SSW. My comments are always based on fact whether you like them or not. :-)
    2 points
  28. I never thought I'd say this but....I'm actually beginning to understand the content of this thread. Recretos you're a genius. Not just for what you know about this subject, but for explaining it in such a way that it gets through my senile, dullard brain and makes sense. Thank you!
    2 points
  29. Actually, it would go perhaps at max to -30 to -25°. Not sure how its averaged. But it surely doesn't go to the max. temp you see on the charts. As far as the zonal wind goes, and the easterly reversal and so on. Allow me to give you a quick crash course (again ) in stratospheric winds. First let me just drop the GEFS 00z trend for the zonal mean zonal winds, which is encouraging for now. Next, let me drop the same parameter, just from the last 3 GFS runs, since there was some talk about reversals. Well, GFS is not there yet. now, when we talk about zonal winds and reversals and so on, what exactly is it all about? I know it must sound confusing. First lets define the wind. Each wind has components. An east-west (zonal) component and a north-south (meridional) component. What these components actually tell us, is how much or how fast the wind or actually the air has "moved" in what direction. For example, if we have a 10m/s west wind, that is 100% zonal wind. But if we have 10m/s of SW wind, that means that it moves 50% to the east and 50% to the north. And those are the zonal and meridional components. here is a visual example of a SW wind. The vj is the meridional component, which tells us how much has the air moved to the north (or south, depending on the direction of the wind) and the ui is the well known zonal component, which tells us how far east (or west, depending on wind direction) has the air moved with the wind. The black arrow is the wind vector, which defines the speed and direction of the wind. In short we usually call zonal u, and meridional v components. Those are also the official definitions in model parameters. Now as far as our strat goes, when we talk about the zonal mean zonal wind, we mean the average zonal component along a latitude line across the globe. The most used example for the strat is the 60N lat line at 10mb. i made an example, from GFS, the 10mb wind speed, with wind vectors. I have marked in circle, the 60N lat line. And around that line is where we usually average the zonal components. here we can see that there is a lot of north-south wind movement, or winds with strong meridional components. And that automatically reduces the zonal wind speed, because there is not a lot of eastward movement along that line. A bit better example is if I change the perspective. We can see how the wind moves generally eastward, but with a lot of north-south movement, due to the wave1 pressure which bends the polar night jet. What is interesting, is that there is little to no westward movement, or zonal reversal as we call it. The main reason why the GFS largely reduces the zonal wind speed, is due to the increase in the meridional component. Or basically the wind blows more in the north-south than west to east as in a perfect zonal example. And an example from GFS, how an almost perfect zonal flow looks like. We can also see this increase on the ECMWF zonal mean zonal wind plots. That plot basically does the same job as my graphic, with the exception, that my graphics shows you exactly where and how much zonal or meridional wind is there at a certain level at a certain point in time, while the ECMWF plot basically just averages all the zonal components from left to right on my graphics and shows you the average zonal component. I also added the same plot for GFS, which practically tells the same story, just now you actually might now how it looks in reality on the normal lat/lon charts. Now if I plot only the west-east or the zonal component, this is how it looks. This tells us how much and where the air moves on a west-east or left to right line. The positive values indicate a westerly wind, while negative values mean an easterly wind. The meridional component then defines if a wind within a negative region is a NE'ly, or a SE'ly. The zonal components define the W and E in the name, and the meridional components define the N or S in the name of the wind. Here we can see that there is basically no zonal reversal going on, Now when we talk about the zonal reversal at 10mb 60N, we do not mean an actual wind blowing in a straight line from east to west, but just simply the majority of the zonal components being reversed, so the wind is NE instead of NW, or SE instead of SW along the 60N line. We basically average (zonaly from left to right) all the zonal components, to see which one is the dominant one. Now the point of this reversal is not in the very wind itself, like the usual "we need that -1 m/s average zonal component, or else there is no SSW and no effect"... There is hardly any difference between a +1m/s average zonal component or a -1m/s average zonal component. except for the purposes of classification and so on... The very point of this reversal is somewhere else, and that is in the fact that as we see how dominant the zonal winds can be in the stratosphere, at that notorious 10mb 60N line (which above indicates a strong vortex), we know that it takes a whole deal of energy, both potential, thermal and kinetic and effort to actually reduce and reverse those zonal components. So the very deal is more as this zonal components being an indicator of the strength of the polar vortex or the polar anti-vortex, or wave activity, or the stratospheric polar high, and so on. When we see the reversed zonal components, where there was +50m/s a few days prior, you know you have a strong and intense process happening in the stratosphere, which can potentially affect the troposphere. So thats why at least to me, its not about the wind if its +2 or -4 or so on, but how fast and how much does the zonal component change, which i use as an indicator of the strength of the processes happening. We also must note, that sometimes when we have strong wave activity, more likely in a wave 2 scenario, the zonal winds can actually increase due to the increasd pressure gradients as the two highs press against the vortex, which by default fights back, and we can sometimes see the vortex actually intensify with a wave 2 activity, especially if the wave 2 is shorter-lived and can leave a stronger vortex behind. So not all wave activity is always good. generally speaking. but as a rule, just remember that the more wave flux you have, the better. As for the downwelling itself, which in this case is not mentioned very often, but that is normal since there is nothing in reliable time frames to talk about. We have to take the connection of the trop-strat into consideration here. is it coupled, is it decoupled? Because if you get a downwelling SSW of a medium strength, which is the most common, in my personal view, it is better to have a coupled trop-strat (logically) preferably a positive AO. Why? because if you have a positive AO, the chances are the tropospheric and the stratospheric vortex are strongly coupled. And as the upper one goes to sleep, the chances are better for the lower one to get hit in a similar way by the "destruction wave". Think of it a as a "channel" connecting the strat and trop polar vortex. Where in a situation where you have a decoupled trop-strat, with no clear definite connection between the strat and trop polar vortex, the upper vortex might fail, but it could not have as much effect on the trop vortex, since it already spins in its own regime, more than being dominated by the strat vortex like in a moderate to strong +AO situations. The effects of an SSW can still come, but might have unwanted effects on the general circulation patterns, basically causing warmer weather in UK and Europe instead of cold, and can sometimes even disrupt the cold patterns already in place. And that is not a coincidence, because if there was already a cold pattern in place, chances are good it was in a negative AO, and if an SSW happened and downwelled at that time into a decoupled system, it could disrupt the circulation and actually cause a shift in wave numbers and positions in the troposphere, enough to create a warm pattern out of a cold one. So there is a reason why sometimes (not that often but it can happen) SSWs can actually cause warm weather instead of cold. We also know that the effects of SSWs are not instant, but can vary from a few days to two weeks or more roughly. So each situation needs specific analysis. This is just some of my thinking, which is not necessarily the same as someone else's, but it could serve you as a guideline or as a basic explanation of why and how strat works the way it does. best regards
    2 points
  30. Well i go to Scotland for two years in a row, to get my snow fix Scotland really delivers for the white stuff, just head for the high ground It was snowing in Glasgow High street last Sunday evening, to the sound of Bagpipes. Fantastic
    1 point
  31. not sure what the point is old chap.... 3 out of 23, possibly 2 more when there was a brief cold spell, thats 17 when there wasnt.... surely that qualifies as 'unlikely' does it not?... i didnt say there WONT be a cold snap... just that its unlikely IF theres no synoptic building blocks to allow one by mid feb (4 weeks time). i cant really see what the issue is
    1 point
  32. The GFS trick known within the magic circle as 'the Phantom Easterly' Now you see it Now you don't Plus a quote from the other thread I'm not at all sure what he's getting at.
    1 point
  33. http://droughtmonitor.unl.edu/ Looks very healthy in the Plains for a change. I'm feeling pretty optimistic.
    1 point
  34. Why would Cameron et al want to shout cobblers? Why would any sane person want to emulate the antics of Palin and Trump?
    1 point
  35. UK Outlook for Monday 25 Jan 2016 to Wednesday 3 Feb 2016: Monday and Tuesday should be mainly cloudy and windy with outbreaks of rain in the north of the country. Drier conditions are likely across southern parts, but even here rain is possible at times, as rain pushes in from the Atlantic. This pattern is expected to persist through the rest of the week and into next weekend, with gales occasionally in the far northwest, along with some snow on hills. As we move into February, a northwest to southeast split may develop, with unsettled weather in the northwest and drier, brighter conditions in the southeast. Temperatures should be around average for much of the country, but slightly below in the south at first with a risk of overnight frosts. http://www.metoffice.gov.uk/public/weather/forecast
    1 point
  36. No extreme heat in Australia this January and there doesn't appear to be a signal for a change in that weather pattern for the rest of the month. Rainfall has exceeded expectations in New South Wales, thru the drought stricken central Queensland area and in central Australia. It may even be a cooler January than average. Tasmania now faces some major economic challenges with the lack of rainfall since the beginning of spring ( a record low total for that season and likely to be a record low spring-mid summer total ). Hydro electricity dam levels are now at 20% of capacity and dropping by about 1% a week. Tasmania's electricity supply is predominately Hydro generated with a small but growing wind component. A gas run power station has just been brought back on line but it is expensive to run, it can only generate about 15% of the islands needs. In 2006 an electricity cable was laid under Bass Strait to connect Tasmania up to the national grid. It too has a limit, capable of bringing in a maximum of 40% of the islands requirements. Just before Christmas a fault cut service to the line. The fault has not been diagnosed, engineers have to drag it off the ocean bed by submarine to investigate, with a timeline for repair near mid March. A near 1% p/w fall in Hydro storage until then will enforce power rationing in the state, for the first time since the 1960s. Farming is also facing a crisis with a lack of fodder for cattle, drying up dams, and massive price spikes for farmers in water costs. On the fire front there are dozens of scrub, grass and bush fires burning across the state ( mostly in remote areas in the usually wet west, and in the north ). There have been no extreme heat events but there's been no rain to put them out in the natural way. Could be a big problem in February in aheat/wind event. In the meantime most of the island is shrouded in haze, it's shifting around at the whim of the prevailing wind. Horrible for people with asthma and respiratory conditions with health alerts to stay inside. Hobart and Launceston this week ( northern Tasmania ).
    1 point
  37. Think we can write of next 4 weeks at least yes people can say about strat warming but I'm not positive about that hope for better winter next year
    1 point
  38. I'd be surprised if we get a SSW by the end of Jan/early Feb but I'm not sure we need it given then the forcing from the trop. All we need is is the continued trop to strat influence and a bit of fingers crossed if you want cold. The signs are in place regarding the MJO and the constriction of the PV shown over current runs. What happens next, if at at all, is like a ball hitting the reds from a snooker break i.e. no guarantee that they end up where you want them. So a bit of short term pain with the constriction and then who knows? Certainly the NWP models have been guessing.
    1 point
  39. Yes, the temps are warming up here for the weekend, up to double figures - wondering if I will be able to go gliding on Sunday but suspect there may be some low cloud which may put the mockers on that.
    1 point
  40. I have a disability myself so why would i be a fan of mocking the disabled? Lfc dude has already answered that anyway.
    1 point
  41. @Cloud10 What I am trying to tell you, is that you must consider the fact that the JMA graphs, like the NOAA graphs are area-averaged. They probably avrage the whole area from 60N-90N, Or 65N or something like that. Your estimate went up to -8, which was the maximum temp on the chart, and not what the JMA would get if they averaged the whole polar cap from 60N to 90N. Even if the very spot of the north pole at 90N would be taken it is still a too big estimate. You must average the entire area to get the temp for that graph, not just the highest temps.
    1 point
  42. Industrial-era global ocean heat uptake doubles in recent decades http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate2915.html
    1 point
  43. I'm afraid not Paul I can only upload through URL address thing quite the mystery.
    1 point
  44. 1 point
  45. UK Outlook for Sunday 31 Jan 2016 to Sunday 14 Feb 2016: As we move from January into February we continue in a very uncertain period of weather. The strongest signal is for the northern half of UK to see an unsettled period, with rain or showers, strong winds and some snow at times mixed with brighter, drier periods. Southern parts in contrast should see drier and more settled conditions with frost and fog at times, although even here occasional rain cannot be ruled out. Temperatures should be generally around average for the time of year, but towards the middle of February the potential for greater incidences of colder weather increases. http://www.metoffice.gov.uk/public/weather/forecast
    1 point
  46. I'm edging towards a 'leave' vote. If it actually happened the UK govt wouldnt pull the UK out straight away - it would force them and the EU 'superpowers' to re- negotiate certain key terms. Yes......vote to leave and the Establishment would have to listen and act.
    1 point
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