TEITS

I don't mean any disrespect to Gibby but I strongly disagree with his summary of the models. Firstly the UKMO has a LP sliding SE and as it does so will pull in colder E,lys into the circulation. The GFS has LPs sliding SE and when you already have existing cold over the UK and cold NW,lys following the sliding LP, then snowfall even at lower levels is likely. The models have certainly changed towards a colder outlook today compared to yesterday.

As the operationals have been covered excellently I thought I would look at the ensembles. Much colder compared to yesterday for my location. http://cdn.nwstatic.co.uk/ensimages/ens.20140123/00/t850Cambridgeshire.png Even Cornwall is around -3C. http://cdn.nwstatic.co.uk/ensimages/ens.20140123/00/t850Cornwall.png Looking at the UKMO and its consistency is very impressive especially with regards to the strength, position, orientation of the block to our NE. http://www.wetterzentrale.de/pics/Rukm1441.gif All models have there strengths and weaknesses. The GFS tends to be very good in a zonal pattern and also handles blocking over Greenland fairly well. The UKMO has always been very good with regards to blocking to our NE, hence why in the past we have always wanted the UKMO on board when E,lys are predicted. As I said many days ago I feel the Met O forecast will change to become more wintry.

Im not surprised to see the fax back the UKMO model. http://www.meteociel.fr/ukmo/fax/fax120s.gif?22-12 E,ly following the LP sinking SE is looking favourite right now. Beyond and its difficult to say except it looks as though it will remain unsettled which isn't good news whether it falls as rain or snow. My hunch is that the outlook could well be colder and more wintry than some are expecting. Shall explain more tomorrow morning.

I can remember it was Jan 2013. http://modeles.meteociel.fr/modeles/gfs/archives/gfs-2013011900-0-6.png?0 ECM/GFS handled the period dreadfully with the UKMO outperforming these during that cold spell.

Mixed views on the output this morning. If like me you haven't even seen one snowflake this winter then the output is positive because all models show a chance of snowfall next week. However if you're seeking a prolonged deep freeze with ice days and widespread heavy snowfalls then the output is disappointing. The pick of the bunch is the UKMO because note the LP makes a clean break and tracks SE. However more importantly note how much further NW the HP is compared to the ECM. http://www.wetterzentrale.de/pics/Rukm1441.gif http://www.wetterzentrale.de/pics/Recm1441.gif Now if the UKMO is correct we could see snowfall on the northern flank of the LP as it clears S. Beyond and further snowfall would be likely as following the E,ly we would see a cold NW,ly. Speaking of cold NW,lys, the GFS is at times a snowy run albeit marginal in some locations. The OP was much milder than the mean around the 31st Jan. http://cdn.nwstatic.co.uk/ensimages/ens.20140122/00/t850Cambridgeshire.png Alot of uncertainty but one thing looks certain is that we won't get a break from the unsettled weather from the Atlantic. Hopefully though this will consist more of snow than rain!

Yes a forecasting nightmare could well be coming up. Seems like we have good agreement of an E,ly as the LP sinks S. However the threat from the Atlantic will continue but with the jet aligned NW-SE these could track SE. Now the combination of cold air already over the UK plus cold NW,lys following the LP from the NW, this could bring frontal snowfalls. So it looks as though at the end of the month a E vs W battle will continue but this time we look to be in a better position for snowfall.

Some excellent runs this morning and you have to say what the ECM is predicting is the most likely based on the model runs over the past few days. My only reservation is something I mentioned many days ago and that is the importance of the LP moving S of the UK. The UKMO is also heading the same way as the ECM. Looking at the GEFS ensembles I think this is the first time this winter the mean has dropped below -5C for my location. Just shows what a crap winter it has been so far! http://cdn.nwstatic.co.uk/ensimages/ens.20140121/00/t850Cambridgeshire.png I can see the Met O outlook changing to a more wintry outlook. Have to be honest I haven't agreed with there outlook these past few days as it appears out of kilter with the model output.

I can simplify it to help newcomers. A pattern change is going to occur and we are talking about charts around the end of the month. The chance of a colder pattern developing is very good as increasing heights to our N appear to force LP S of the UK. So anyone saying no signs of any cold spell are wrong. However that does not guarantee we're going to be hit by a big freeze. We are going to see a pattern change and this is our best chance of winter arriving in the UK. Looking at the 12Z GEFS ensembles this is the fifth run on the trot to show the SLP at 1030mb for Iceland. This might be higher than the mean but just watch that mean increase over the next 24/48hrs. http://cdn.nwstatic.co.uk/ensimages/ens.20140118/12/prmslReyjavic.png

They are highly unusual, I have never seen charts like they currently show in over 4 years of intensive watching them every day.I keep saying, interesting, but it really is, well to me, whatever follows. I agree John and without being rude to any members I feel some are missing the bigger picture in their quest for a snowflake. The pattern WILL change but for the moment we have no idea how this will pan out for the UK. However for a cold spell in the UK you need the ingredients and so far this winter we haven't had any. This isn't the case based on the output and we just need them to come together. If I come off the fence my instincts are telling me we are in for a superb cold spell beginning end of Jan with a N,ly with this cold spell reaching its peak via an E,ly around the end of the first week of Feb. I would expect this to continue as Feb is likely to be cold and much drier with plenty of blocking HPs. Quote got messed up. I was quoting John H post.

Well the peachy charts I have been expecting have arrived. I have been following the Iceland SLP ensembles and note how the operational has much higher pressure than the mean. http://cdn.nwstatic.co.uk/ensimages/ens.20140118/00/prmslReyjavic.png This has been the case for several runs now and combined with the ECM it illustrates the operationals are what you need to follow. The GEFS ensembles will be playing catch up on this. Back to the ECM/GFS and note how the increasing heights to our N are forcing the LP to track south of the UK. I would be wary of this at the moment because at this range I have seen this before only for the LP to sit across the UK rather than clearing S. http://www.wetterzentrale.de/pics/Recm2401.gif My overall summary though is very positive. Forget about looking for an E,ly in the nearer timeframe because as you know I have never fancied this occurring. The real action is towards the end of the month when a massive change is going to occur. The combination of the Arctic HP, Scandi HP, lack of LP tracking across the Atlantic, bitter airmass moving S from the pole, will provide some very exciting model watching days ahead of us. However this pans out for us there is no doubt a change from the weather pattern we have seen so far this winter is going to occur.

Depends because yes sometimes blocking to our N/NE doesn't deliver especially if we have a W based negative NAO. However sometimes it does i.e 2009/10. Using the GEFS ensembles for the period we are referring to i.e late Jan is pointless. I would rather use seaweed or a certain forecaster that the Daily Express uses for forecasts! Very much expecting some peachy charts to appear from the GFS over the next few days including the ECM when it comes in range.

Just a quickie. Looks like this stalemate is going to continue but personally I don't care as the end of Jan/early Feb is more interesting to me. The models suggest increasing heights across the pole with winter arriving in the UK from the N, not the E. Also the E side of the US/Canada will also be hit by a big freeze whilst the W remains milder.

Don't forget the 10% chance that the Met O mention is based on previous days outputs. At the moment 24hrs is a very long time and this is especially true with this current pattern. Personally the chance of marginal snow fall via a relatively cool E,ly flow has increased somewhat this morning. I still believe the last week of Jan/ 1st week of Feb is when winter will properly arrive from the E.

Looks like the models has made those, and I include myself, look right fools saying no chance of an E,ly and a return to mild W,lys is a certainty. http://www.wetterzentrale.de/pics/Recm1681.gif I should not be surprised though because after years of following the models its pretty obvious the models have a flaw in the programming when low pressure comes up against blocking to our NE. Nearly every time the models want to blast the block away to the E allowing this return to a W,ly pattern. What is clearly happening is we are seeing the usual shift W of the pattern by the models and today/tomorrow we should keep an eye on this continuing especially around the +72 to +120 period. I still doubt a typical deep cold E,ly is likely simply because the main cold pool is so far away. However we could yet see a marginal snow event come from this. Having said I got it wrong I did say this yesterday. http://forum.netweather.tv/topic/78680-model-banter-moans-and-ramps-winter-201314/page-43

Rather premature to write the whole of Jan off just yet as +384 takes us to the 31st. I always had a feeling the first attempt at an E,ly would fail. However the 2nd attempt would be more succesful and I shall stick with my instincts and suggest the last week of Jan is when winter will finally arrive. Im not expecting the period of W,lys to last very long before we see more trough disruption but this time successfully moving SE allowing colder NE/E,lys to arrive.

Still unimpressed with the output including last nights ECM. The block to our NE still does not look like bringing anything wintry and in my opinion is only delaying the inevitable return of a more mobile W,ly pattern. The only positive is the delay reduces the chances of further flooding.

Depends because their are many different types of E,ly and on todays ECM your 9 out of times comment isn't correct for whats being projected. If todays ECM was predicting -10C E,lys then I would agree with you. Personally what the ECM is projecting is perfectly plausible but unfortunately the chances of a deep cold E,ly are extremely unlikely. For starters the core of the cold is to the NE of the HP and if we compare to the chart below you see the complete opposite. http://www.wetterzentrale.de/archive/ra/1987/Rrea00119870109.gif Finally if we skip between +168 to +240 the core of the HP is actually moving E rather than extending W. So from a point of view of looking for cold & snow im disappointed even with the ECM output. Cannot help but be in awe of that Jan 87 chart. The perfect E,ly with part of the Polar Vortex sitting underneath the Arctic HP.

The reason this has gone pearshaped is its called "the curse of telling your friends and family a cold, snowy spell of weather is on its way". As soon as I do this the models flip!!

Well it looks as though a post of mine a few days ago saying the first attempt at a E,ly will fail was completely wrong. Rather unusual watching this unfold because im so used to following E,lys from +240 disappear at +72. On this occasion we are seeing upgrades at a much earlier timeframe. If we look at the GEFS ensembles for my location they clearly show whats going on. http://cdn.nwstatic.co.uk/ensimages/ens.20140108/00/t850Cambridgeshire.png Note how closely the control follows the OP and combined with the other models then if the operationals of the ECM, GFS etc continue the same then in a few runs time that mean will be around -10 to -12C. The way this is likely to pan out is a front will attempt to move SW to NE but become stalled somewhere with a chance of snow. The LP will sink S allowing a colder E,ly flow to establish with snow showers into E areas. At this stage it doesn't look to be the coldest or longest in duration E,ly I have ever seen but its far better than the rubbish we have endured so far this winter. Having said this though the way the models are upgrading it would be foolish of me to predict the severity or end of this coming cold spell.

Historically the models have always struggled in these situations. The GFS is useless and really isn't worth paying attention to. The ECM can be the other extreme being rather OTT with the blocking and then you have the UKMO which often handles these situations more accurately. My instinct though is telling me the first attempt at a cold spell from the E/NE will fail and the cold will not get further W than E Germany. However the 2nd attempt will be successful around the period between 20th-23rd Jan.

I shall add to this by saying that I would be very surprised if we didn't see a pattern change very soon. Our climate is notorious for being changeable and no spell of weather lasts for very long whether this is stormy, cold or dry and settled. We have had such a stormy, wet period I would be amazed if this continued for the remainder of Jan.

Worth mentioning that the Met O spotted the Dec 09 cold spell weeks in advance even when it was not apparent in the model output. I have not posted much recently because im clueless what the outlook will be. You only have to look at the past 3 ECM runs to see big differences in the +168 to +240 range. I could make a case that mild, zonal is the likely outlook but I could also say the same for a cold E,ly. Its also worth adding that E,lys are extremely fickle because they can simply disappear from the model output even at +96 but can also reappear quiet suddenly, Dec 2005 springs to mind. For the time being im going to quietly follow the models and continue to read the updates from the experts at the Met O. If they believe a colder spell of weather is on its way in 15 days time then thats good enough for me.

Some interesting posts. A pattern change is going to occur over the next 10 days but how will this impact us here in the UK is the big question for me. If we look at the link below you will see all of Europe is mild. http://www.wetterzentrale.de/pics/Rtavn062.png What is likely to happen is a very cold surge is likely to spread S into Russia and E Europe during the first week of Jan. However as per usual will this advect W and reach the rest of Europe including the UK is always uncertain especially at this range. Our chance of a cold spell is most likely to come from the E as opposed to a N,ly, however it could begin by a brief NW/N,ly if LP systems start tracking on a SE,ly trajectory. At this stage I feel its foolish to assume our mild, stormy weather is going to continue into Jan. Im expecting the model output between +192 to +240 to swing wildly over the next few days which is why nobody can be confident of the outlook yet. The only confidence I have is a pattern change is going to occur but will it impact the UK??

I feel I need to add some balance because the word "Mild" is being incorrectly used for the outlook period. The 06Z is a good illustration of what i've been harping on about. If we look at the charts below you would assume mild. http://www.wetterzentrale.de/pics/Rtavn2041.png http://www.wetterzentrale.de/pics/Rtavn2042.png However due to HP, flow off continent the majority of us would actually see chilly max temps during the day and frost at night. http://www.wetterzentrale.de/pics/Rtavn22817.png Just remember mid Dec is when you can experience the coldest temps under such synoptic set ups and one of the main causes is the lack of daylight hrs. I have known ice days, well below freezing mins and hoar frost remaining all day under these conditions. Should mention all of the above does not apply to extreme W/SW!

Little change for me in the output. A dry, settled outlook although temps still look uncertain except the extreme W/SW where it could be very mild. Still the risk of Central/E/SE being cold during both night and day. Ensembles show this clearly with a mean SLP between 1020 - 1030mb. http://cdn.nwstatic.co.uk/ensimages/ens.20131204/00/prmslCambridgeshire.png A bitter E,ly is still a long shot. If we look at the Berlin ensembles only one member suggesting a very cold airmass. http://cdn.nwstatic.co.uk/ensimages/ens.20131204/00/t850Berlin.png A rather boring period of weather coming up to be honest.