Model Output Discussion - 05/01/2016 18z onwards

[tight isobar]

Yes the Canadian lobe wants to hold its hands up against further height rise @greenland. not to concerned! 

[Rocheydub]

Just now, Ali1977 said:

Yeah didn't expect it to look wrong this early, still shows some volatility in the outlook...still, let's wait and see

How does it look wrong? I'm sorry, but the broad picture remains the same. It's still absolutely game on, and we're well into FI now on this run. I'm more than happy with it I have to say, a much earlier incursion of the cold than the 12z run. Nothing wrong with it IMO.

[Geordiesnow]

3 minutes ago, feb1991blizzard said:

There is a danger here looking at the flow around SW Greenland that we end up with SWerlies at around 240, hope not but.....

I won't care if it does as its at 240 hours, its around 138 hours there is changes in how the ridging plays out but it will be subject to change so I don't think there be too much to worry about if we do see a west based -NAO on this run. 

Either way, its another cold run and a good run also imo. 

[chicken soup]

Remember this is 18z not the most reliable run of the day...its not called the pub run for nothing....all will be well come the 00zs in the morning.

 

[winterof79]

Just now, Rocheydub said:

How does it look wrong? I'm sorry, but the broad picture remains the same. It's still absolutely game on, and we're well into FI now on this run. I'm more than happy with it I have to say, a much earlier incursion of the cold than the 12z run. Nothing wrong with it IMO.

Quite correct do not fall into the trap of over analysing every GFS run.You will end up on Prozac.

[damianslaw]

A cold period shown by all models today, notably cold as well. ECM backtracked and showing a very cold sustained period, with Greenland heights and scandi high, more of an east based negative NAO solution, winds from the NE..

GFS has trended with the Euros, but may be hinting at the ridge being a bit further to the west.

Either way - the trend is for much colder weather for all, plenty of frost and temps below average, perhaps notably so. Forecasting snow at this range is a waste of time - will be a case of nowcasting, however, from a NW perspective, there appears to be a trough/low pressure system development in the NW flow mid week which would very much bring snow to low levels.

 

[radiohead]

3 minutes ago, Ali1977 said:

Yeah didn't expect it to look wrong this early, still shows some volatility in the outlook...still, let's wait and see

The ridge being skinnier and further west wasn't an encouraging sign. 

Now hopefully we don't see this replicated on the 0Z runs. 

[swilliam]

1 minute ago, winterof79 said:

Quite correct do not fall into the trap of over analysing every GFS run.You will end up on Prozac.

Yes that is fine as long as it does not become a trend (i.e we something similar in the morning and then the ensembles show it more)

[feb1991blizzard]

1 minute ago, Geordiesnow said:

I won't care if it does as its at 240 hours, its around 138 hours there is changes in how the ridging plays out but it will be subject to change so I don't think there be too much to worry about if we do see a west based -NAO on this run. 

Either way, its another cold run and a good run also imo. 

True but is this the reason the MO are still doubting longjevity, this really is the one synoptic that can render this spell very short, if it topples from that postion it will bring an Easterly but the West based scenario is the one that can scupper it.

[Rocheydub]

1 minute ago, damianslaw said:

A cold period shown by all models today, notably cold as well. ECM backtracked and showing a very cold sustained period, with Greenland heights and scandi high, more of an east based negative NAO solution, winds from the NE..

GFS has trended with the Euros, but may be hinting at the ridge being a bit further to the west.

Either way - the trend is for much colder weather for all, plenty of frost and temps below average, perhaps notably so. Forecasting snow at this range is a waste of time - will be a case of nowcasting, however, from a NW perspective, there appears to be a trough/low pressure system development in the NW flow mid week which would very much bring snow to low levels.

 

Copy and paste this for every future: "Oh, this looks worryingly different at 72 hrs" post from here on. Bravo sir!

Edited January 6, 2016 by Rocheydub

[bradymk]

A great day. Awesome ECM run, best we've seen for a long time. Talk about going from one extreme to another with December's records to a possible very cold end to January. In regards to MetO, I would hedge my bets that tomorrow is an important day regarding there outlook. If we have a solid day again tomorrow just like today, there outlook will change. There clearly supporting the cold outlook, but not public on the longetivity and potency yet...

[gottolovethisweather]

1 hour ago, Biggin said:

I was beginning to think along similar lines, is the climate going a bit into unknown territory? ie behaving a tad unusual than in the past??

Its not really discussion for this thread BUT being as Svalbard (positioned between Norway and the North Pole) recently had an anomaly of +17c I'd say all that additional heat would cause mayhem somewhere in the globe. 

 

EDIT: I had quick look around the web and I believe that figure should read +17f  in old money it is still more than 10c above the norm and that is breathtaking enough. 

Edited January 6, 2016 by gottolovethisweather

[winterof79]

2 minutes ago, swilliam said:

Yes that is fine as long as it does not become a trend (i.e we something similar in the morning and then the ensembles show it more)

Look at John Holmes's post for trends.

[chionomaniac]

Wouldn't be surprised to see the block reinforced dragging in a bitter NEasterly

[swilliam]

Just now, winterof79 said:

Look at John Holmes's post for trends.

That was based on the 12Z

[ukpaul]

Two issues combining here, changing the position of the Arctic high, pushing the WAA west and a low pressure feature that refuses to move to the northwest of Scotland, which is then ignominiously forced to drift southwards, dragging warm sectors with it. The former is one to watch but the latter is a here today/gone tomorrow feature.

[winterof79]

1 minute ago, swilliam said:

That was based on the 12Z

ok.I'll leave you to it.Enjoy.

[nick sussex]

I think the first  issue with this GFS run is the Iceland bulge!  Its trying to develop a shortwave and this sticks out into the Atlantic, we want rid of this. There are also some changes with the troughing make up over the ne USA.

 

 

 

[swilliam]

1 minute ago, winterof79 said:

ok.I'll leave you to it.Enjoy.

Well I am expecting and hoping that it is not a trend - we will see in the morning.

[Liam J]

16 minutes ago, feb1991blizzard said:

There is a danger here looking at the flow around SW Greenland that we end up with SWerlies at around 240, hope not but.....

You may be right about this run! 

[PolarWarsaw]

As mentioned earlier, nothing set in stone as much as we would want it to be. 18z isn't the most reliable run of the day, but it hasn't been known to pick up trends (something that the GFS is well known for doing). Personally, I think this run will be closer to how things end up being. I can't see the beautiful synoptics of the 12z coming to fruition - BUT, I also don't expect this to be a 2 day toppler. I think we will be somewhere in the middle. 3-5 days of much colder weather. Frosts for ALL and snow for favoured areas of Scotland/Ireland - these look a cert to me. 

 

Let's hope we see a bigger wedge ridging into Greenland come the 0z. Can't see it myself, but we definetely have a good shot at it. 

 

Night all.

[Ali1977]

hopedully an outlier within the ensembles, still a pretty good run though.

Hopefully still a signal for an SSW event in FI though.

Edited January 6, 2016 by Ali1977

[Met4Cast]

Yes, let's all get upset over a single operational run. We don't even know if this new "trend" as some are already calling it is supported by it's ensembles.

This is but a single run, one option of many of what could happen come next week. The trend on the 18z continues to be that colder weather will flood across the UK next week. Beyond that has always been in doubt. Can we maybe try being more objective instead of throwing toys out of the pram because our Atlantic high has been to slimming world?

Edited January 6, 2016 by Daniel Smith

[nick sussex]

In terms of the GFS 18hrs pattern in the ne USA and Canada, this looks a no go in terms of what the PV is supposed to do. That's expected to remain over Hudson Bay. And the associated troughing expected to remain amplified.

The earlier shortwave though near Iceland is something that we need to watch.

[swilliam]

3 minutes ago, Daniel Smith said:

Yes, let's all get upset over a single operational run. We don't even know if this new "trend" as some are already calling it is supported by it's ensembles.

This is but a single run, one option of many of what could happen come next week. The trend on the 18z continues to be that colder weather will flood across the UK next week. Beyond that has always been in doubt. Can we maybe try being more objective instead of throwing toys out of the pram because our Atlantic high has been to slimming world?

No-one said it was a trend and no-one is getting upset - just commenting on the run. I said it was a problem if it became a trend.

Edited January 6, 2016 by swilliam