Model Output Discussions 06z 04/11/16

[Summer Sun]

Lot's of scatter on the latest NAO update still every chance it will remain negative

Edited November 20, 2016 by Summer Sun

[blizzard81]

14 minutes ago, phil nw. said:

It looks like 5/6 days of quiet weather under a mid-latitude high across the UK from around mid week before any further changes.

From what i can see further on is that we have a weaker set of +ve hts across Greenland with the main core moving west towards Canada at day 10.On that basis it's difficult to see a way that any deep cold  will come south to the UK-we do need to see more solid blocking around Greenland for that.

Day 10 Ht anomaly charts

Those heights do keep the mean path of the jet further south towards us so after the rather cold high at the surface the most likely development is more changeable but rather cold weather as the high fades.

A look at the London graph

 

shows temperatures dipping to just below  average towards month end.There some colder members but as ever at the later range we need many more showing before we can expect a real cold spell as we go into the new month.

I think the one thing we can take from the latest outputs is that we have no strong signal for a period of mild south westerlies from a traditional early Winter raging jet.

With regards to the high being too far west (over north east Canada) as opposed to Greenland, I remember GP posted the other day that this may help to raise heights over Scandi/Barents Sea. Maybe something to look out for in the 10 day plus range.

[Gael_Force]

45 minutes ago, nick sussex said:

Yes but NCEP in doing their monthly forecast use a wide range of models so I would have thought they would include the GEM and ECM. I hope the USA isn't going to steal our cold again!

There's a lot of N American models and they all, bar one, forecast very positive anomalies for the US in December.

http://www.cpc.ncep.noaa.gov/products/NMME/current/ustmp2m_Lead1.html

If I'm reading between the lines correctly, they're saying what should happen with -AO is not necessarily what you'll get as NH mode is a bit lopsided atm.

 

[Banbury]

1 hour ago, blizzard81 said:

Sort of ties in with the lt meto forecast of more unsettledates, windy weather as we hit Dec. A bit of a change from a couple of days ago.

Wrong thread , but that's not what the latest says at all ??

[blizzard81]

The NAO update kindly posted above is much improved on yesterday's update. As is the AO update. Maybe some decent 12z runs to come later?

Edited November 20, 2016 by blizzard81

[blizzard81]

2 minutes ago, Banbury said:

Wrong thread , but that's not what the latest says at all ??

25th Nov - 4th Dec forecast ends with potential for more unsettled, windy weather at the start of December.

[Polar Maritime]

Just the Models Outputs please, Thanks.

[Methuselah]

How odd...After 24 hours' connectivity problems, I come back a few runs later to find that the models have flip-flopped at T+384?

But, unless I am barking up entirely the wrong tree (not unheard of!) things are still looking good for at least a few days' frost and fog - before something happens...Will the HP retrogress towards Greenland? Will it sink away to the SW and introduce an Atlantic influence? Or, will it become a beastly Bartlett?

So, do not despair or assume the worst - many of the seasonal signals would still favour a retrogression toward Greenland over the other two options - I take the uncertainty highlighted by Fergie to be a major positive, this time round...It is, after all, only November 20!

 

 

[Sweatyman]

2 hours ago, blizzard81 said:

I'm beginning to think that any significant UK cold will have to wait until the middle of Dec. The trend with the models has been to delay any early Dec cold and move it back somewhat. On a positive note though, I am looking forward to the seasonal dry, frosty, foggy weather heading our way later this week

God the patience word will start again. It'll be end of December then wait til January etc

[blizzard81]

2 minutes ago, Sweatyman said:

God the patience word will start again. It'll be end of December then wait til January etc

Got a feeling the 12z runs will please most on here tonight.

[Frosty.]

5 minutes ago, Sweatyman said:

God the patience word will start again. It'll be end of December then wait til January etc

More runs are needed!

There are more positives in the extended range compared to this time last year when it was all negatives staring into a mild abyss.

[Sweatyman]

5 minutes ago, blizzard81 said:

Got a feeling the 12z runs will please most on here tonight.

Hope so blizzard!

[Frosty.]

8 minutes ago, Sweatyman said:

Hope so blizzard!

Regarding the comment about the 12z likely to be more pleasing on the eye for coldies,  either which way I'm not just hoping for more wintry low res, I'm expecting it more often than not. I'm also looking forward to the frosty fine weather that the models are firming up on..there could however be some persistent fog which would make affected areas very cold by day, maybe hovering around freezing or just above.

Edited November 20, 2016 by Frosty.

[Singularity]

I believe we are in a time of exceptional unpredictability due to many extremes of atmospheric state taking place at once, which is increasing both the likelihood of errors in modelling and the extent to which errors can amplify into large discontinuities between models and runs.

Strength of mind will be needed to withstand this.

Edited November 20, 2016 by Singularity

[igloo]

On 11/18/2016 at 22:33, Frosty. said:

On 11/18/2016 at 22:41, Catacol said:

there is a huge difference between this time last year to now. the state of the PV is very near non existent even when you go back to the the extreme of 1962-63 you can still see a big blob of PV over the hudson bay but still it delivered the coldest of 1900s 

 

 

 

 

 

Edited November 20, 2016 by igloo

[Ali1977]

To me this already looks better st 162, especially in the Newfoundland area.

Where on the 06z a low formed in that area stopping the PV head south East it hasn't this run, allowing slightly higher pressure to form behind it which could get us back in line with the 00z. We shall see.

Edited November 20, 2016 by Ali1977

[booferking]

This run is looking better the high is closed of east and pushed further west.. better heights getting into Canadian area

[knocker]

MV tweeted this yesterday but also gives an idea of the EPS ext 500mb anomaly

 

Edited November 20, 2016 by knocker

[Ali1977]

Now we need the WAA in the Atlantic to head through the gap towards Labrador then its game on.

[Cheshire Freeze]

Surely that one conveniently placed shortwave isn't going to stop the retrogression is it??

This is the UK...it probably will!

[Jonan92]

Big are of high pressure in the pole (1030hpa)

 

[bobbydog]

1 minute ago, CreweCold said:

Surely that one conveniently placed shortwave isn't going to stop the retrogression is it??

This is the UK...it probably will!

Hopefully not. The lobe over the north west is moving (painfully slowly) in the right direction. If it can reinforce the scandi trough then it should end up like the 00z. Come on GFS, the force is strong...

[Frosty.]

3 minutes ago, CreweCold said:

Surely that one conveniently placed shortwave isn't going to stop the retrogression is it??

This is the UK...it probably will!

Shortwave drama..you can tell its almost winter!

[Ali1977]

Shortwaves are weakening, replaced by Heights this could be a great run. 

So slow, it's like the UK has a little forcefield to the North stopping anything entering without a battle !!

Edited November 20, 2016 by Ali1977

[Cheshire Freeze]

2 minutes ago, bobbydog said:

Hopefully not. The lobe over the north west is moving (painfully slowly) in the right direction. If it can reinforce the scandi trough then it should end up like the 00z. Come on GFS, the force is strong...

How the hell did we get into a position where heights to our S are an issue?