Zak M

Snow? What's this 'snow' you speak of? Anyway, back to the models. P29 is a stonker...

Here's the ECM 500hpa anomalies for the second week of December.

12z GFS is showing a bitterly cold northerly at around the T300 hrs mark..

Just flicked through the 12z GEM ensembles and quite a few perturbations are showing some colder options on the table. The GFS is also showing some colder perturbations too. ECM mean @240 is showing the building blocks of a northerly, with height rises in the N Atlantic: And look at the ECM clusters... 33/51 of them are showing some sort of northerly at around day 10-11 - some agreement there but we need this to be in the reliable timeframe (<5 days) So there is clearly some signals for a colder start to December... overall it’s looking positive going forward. Let’s hope some of these charts actually verify this time! (Narrator): They didn't...

GEM at 240 lines up a northerly: Think there’s a reasonable chance of some cold weather at the start of Dec.

Take a look at those uppers on this mornings ECM run... reaching near -16c in the Shetland Islands!

Clear skies here has lead to the sight of Jupiter and Saturn to my south.

The GFS parallel is hinting at something a bit different ...

And here’s the uppers... Very good chart!

Some similarities between the GFS control and op run...

Pub run is going bonkers as usual...nothing to see here! It's even having a go at another shot too. Some very cold 850hpa temps - uppers in excess of -16c near SE Iceland and NW Scotland..

Nights and evenings will start to get lighter in 4 weeks. Thank the lord. Absolutely hate these dark evenings.

Ladies and gentleman... I present you perturbation 19. Crikey!!

Looks like a few lightning strikes have been detected over Scotland and the Shetland Islands this morning, including a 743kA positive strike. That amount of power is hard to fathom.

Lucky you @Tamara! It's been a day of endless cold and rain here. Currently 8c. I'd love to stay in Portugal during the winter! I would prefer days of sun and 20c rather than cold rain and single-digit temps.

As much as I hate to say this, the CFS isn't a reliable model to use for looking what this coming winter may bring I'm afraid. In fact, some reliable models even struggle nailing down details at day 4!

Evening all. I'm a bit bored this evening. In fact, I'm always bored at around this time. So there might be a long post coming up. I haven't even finished yet so I don't know how long this post will be Some great posts tonight, by the way. Thanks to all the members that contribute in this thread. I really appreciate it. My emotions were a bit mixed tonight, when I saw the charts. Obviously I hate the cold (I don't mind it when there's snow or a storm overhead at the time), but the GFS and it's other runs might be quite good in terms of snow and I like snow. It's way, way, way (x2000) out into FI however, so anything could happen haha. The ECM looks a tad underwhelming if it's cold and snow you're looking for. Here's the day 10 chart: That ridge gets pushed away too quickly by the raging Atlantic. If that ridge stayed there and slowly migrated to the NE, then we may have a decent chance of some cold arriving from Europe or Scandinavia. The chart is quite good for the hills of Scotland though. The -4c isotherm is present, so I would expect some snow to fall on higher ground in the north if that chart verifies. Other models, like the GFS and GEM, show the most cold potential. The goofus, its control run and its other perturbations, are the best models tonight for any cold/snow potential. The blocking over Scotland/Iceland allows some cold from eastern Europe to travel westwards and eventually reach the UK (it's important to note that not all of the GFS perturbations show this). A few of the GFS perturbations actually drag even colder uppers from the north because of a blocking that establishes itself over the Atlantic and Greenland, which then introduces a very cold northerly to parts of N England at T384. The GEM is quite similar to the GFS, and includes the blocking but this time, the GEM has it further east over Scandi, and doesn't allow the uppers to travel as far as the UK. If the GEM had the same timeframe as the GFS, then we might've seen the cold eventually reach the British Isles at around the T300 mark. The 18z GFS shows the blocking near Scandi, but it arrives later this time, and the cold only gets as far west as Germany. Next up, the ECM clusters. The picture above is the ECM clusters for day 7. Literally all of them have the high slap bang on top of the UK. If we fast forward right to the beginning of December, they show this: Both are showing above average heights in or near Greenland, which is a good start. The first cluster doesn't look like the best however, with above average heights to our south and east, which makes that cluster look like it would deliver some mild and wet weather if it verified. The next cluster, however, could indicate something more colder to come. Obviously, these are only the 500hpa heights, so it's quite hard to tell how cold that cluster could be. But above average heights over Greenland, below average heights slap bang over us, and what looks like above average heights just in the frame near Scandinavia, is usually a good sign if we want to crave some colder weather. I stumbled across ECMWF's website for the first time (yes, you read that right!) and found some interesting features that they added a couple of months back. I found a chart which showed the 500hpa geopotential anomaly for the ensemble mean in the NH view, which updated earlier today. I had a look through it, and the first two weeks showed above average heights to our south and east, but it showed this for the end of November and the start of December (charts both linked below if you want to have a proper look at all of them): ECMWF Forecasts WWW.ECMWF.INT It looks very similar to one of the ECM clusters I posted above, which includes above average heights near Greenland and Scandi, and below average heights near the UK. I don't know much about this chart or this feature, so I'm not entirely sure how accurate this is, but could we see a cold end to November and start to December? The ECM clusters and the GFS also thinks so. And lastly, here's the GFS/ECM 8-10 day 500mb mean: They're both not the best and don't really look like they are showing something cold for us. We really need that HP cell over NW Europe to migrate either northwards or eastwards for the better chance of seeing any cold. But I'd rather hear the opinions of two far more experienced and knowledgeable people: @johnholmes and @mushymanrob, and even a few others! Oh, I'll include this too. So, it's rather uncertain as for what could happen at the end of November and at the start of December. For now, I'll be sitting on the fence. I still have a feeling that this winter will be more snowy than the previous few. I unfortunately don't have much evidence of that happening at the moment, but it's just a feeling from my gut! As always, please let me know if you spot any mistakes I have made. I'm still a teenager and have only been watching the models for just over a year, but with all these wonderful posters, I'm always able to learn more things everyday! Have a good nights sleep all. Each day is a step closer to winter. ZM

Sorry for my above post, I couldn't help myself. I need to teach myself better next time. Yes, it looks similar to its op run too, but instead the cold uppers from the continent actually reach us: Judging by the last two frames of the control run, that HP cell to our north seems to stall there, so the uppers from the continent might keep on coming..

And here's T384... look at that cold pool to our north.

Seriously cold uppers start to flow southwards on the 12z GFS. I'm waiting to see what T384 will look like. Could potentially be a stonking chart for snow. The 12z GEM is also quite similar to the GFS: What could possibly go wrong!

GFS quite similar to its previous run. Except it has much colder uppers coming our way from the continent...

Just seen a distant lightning flash and it was quite bright considering how far away the storm is.

If the GFS went up to 400+ hrs then I wouldn't be surprised to see a cold shot lead by possible blocking over Greenland, Iceland and the N Atlantic. You can also notice some cold air arriving into C. Europe, we would need that Atlantic blocking to migrate westwards for any chance of some cold coming from the continent. The 12z GEM is quite a chilly run with the cold nearby into Scandi as the jet dives south - way into FI of course Could this be a very good NH pattern as we head into December? Asking for a friend..

First lightning strikes inland are in Dorset. Meteologix has three of them detected as +CGs.