Model Output Discussions 06z 04/11/16

[feb1991blizzard]

7 minutes ago, swfc said:

at 192 check out the tip of greenland on the 12z to the 18z .change a foot on this run.scandi high for me 

Greeny for me - just differing route.

[Snowy L]

That gap between between East Canada Low and Iceland Low is far small close for comfort. Though should the GH materialise it hopefully means no West Based NAO.

 

Edit: Or no negative NAO at all. Quite the collapse.

Edited November 17, 2016 by Snowy L

[bobbydog]

15 minutes ago, Barry95 said:

First it was the middle of November, then the end of November, and now the start of December for the pattern change to significant blocking! Let's hope this isn't a theme of this winter as I have dejavu of this thing happening  from the last couple of winters. A couple of days ago Ian posted about a strong signal towards a more blocked pattern, with GLOSEA and MOGREPS both supporting that. But less than 24 hours later, the signals towards a more blocked pattern had already waned, which goes to show just how hard it is forecasting the weather anymore than a week in the UK. I'm currently not getting excited just yet as all the blocking charts seem to be remaining in the 10-15 day timeframe. The GFS 12z run everyone was getting excited about has already changed  on the 18z. The Northern Hemisphere background does still look much better than last year, but all the good background signals in the world don't gurantee cold/snowy weather for the UK. Until these blocked/cold charts get to at least day 7, theirs no point getting too excited in my opinion.

 

Erm... this is now. The 17th of November.

That's significant blocking....

[Frosty.]

All roads lead to cold..hopefully! 

Another very encouraging run for coldies from the Gfs 18z with arctic air & snow featuring, especially towards the end with cold reload potential from the nw / n.

Edited November 17, 2016 by Frosty.

[Geordiesnow]

4 minutes ago, bobbydog said:

Erm... this is now. The 17th of November.

That's significant blocking....

Well he clearly means blocking which affects the UK weather in a cold snowy type of way and he's right really, people do mention dates as a potential of interest then its keeps getting dragged further and further back where it becomes laughable really.

I do think the outlook is interesting and you can't rule significant cold set ups for sure but as of yet, the models havant exactly shown much in the way of significant cold set ups which is sometimes a good thing as something unexpected can sometimes pop up at more shorter notice instead of following a cold set up at 200 hours hoping it will become reality.

[Nouska]

15 minutes ago, bobbydog said:

Erm... this is now. The 17th of November.

That's significant blocking....

Indeed! and as they give details on anomalies, a look at those for today.

 

Substantial high level blocking to the north, north west and north east. 

Precisely as detailed in updates from professional sources.

It is the middle of November and already two cold shots with snow for some.

CET for first ten days coldest since 1980 (from CET thread).

That's good going in my opinion - both from the models .... and the weather.

Edited November 17, 2016 by Nouska

[Zakos]

Im amazed at the continuity of the blocking in the atlantic. 3 day snapshots of the 18z run show positive height anomalies in the atlantic for the entire run.

 

By far the best NAO forecast this season.

 

 

 

 

[bobbydog]

Just now, Geordiesnow said:

Well he clearly means blocking which affects the UK weather in a cold snowy type of way and he's right really, people do mention dates as a potential of interest then its keeps getting dragged further and further back where it becomes laughable really.

I do think the outlook is interesting and you can't rule significant cold set ups for sure but as of yet, the models havant exactly shown much in the way of significant cold set ups which is sometimes a good thing as something unexpected can sometimes pop up at more shorter notice instead of following a cold set up at 200 hours hoping it will become reality.

The point is, it is (or has been) showing blocking in many forms through to the end of the month. Normally we are looking for the slightest hint that blocking might even occur during winter at this time of year. The problem is, as soon as it appears, people expect to be building snowmen in the garden within a week. It's November. It won't happen yet. I'm not expecting it yet. I do however, think that we are seeing weather patterns right into the stratosphere which will mean that when winter does arrive (and there's officially 3 months of it) even where I live in the snowless south, my daughter Molly will be building her first snowman ever. And she's 5 in March!

[Frosty.]

7 hours ago, Barry95 said:

First it was the middle of November, then the end of November, and now the start of December for the pattern change to significant blocking! Let's hope this isn't a theme of this winter as I have dejavu of this thing happening  from the last couple of winters.

 

It's good news that the HLB is delayed, gives us more chance of potent wintry weather when it matters, in winter. I can't see any downgrades in the models or the MO updates either..patience grasshopper! the fantastic updates from SM, GP and Tamara, to name but a few, are also very encouraging.

Edited November 18, 2016 by Frosty.

[joggs]

 No charts to post but a little something I've picked up on here over the years.Don't get hyper on every run fgs.

Look at the more knowledgeable on here and take a 24 hr run and take the same run a day later etc.

No wonder there's toys out of pram and one liners that don't add anything to the thread.

The UK is in a good latitude but alot of others things going against us if it's cold winters your after but enjoy what we receive.We're always on the edge of something good (so it seems lol)but there's going to be more mild winters than not.Accept it.

Enjoy the ride and don't be too down when things go against the grain.

Also(and it might ruin the way people do thingso on here)I read the metoffice outlooks before reading the models(they are pro's but not untouchable)they give you a good guidance and you won't led down the garden path as much.

But if you like that sort of chase,ignore this post lol.

All the best everyone needs here's hoping you sell get the weather you're after(mild or cold).

See you all around.

[Ross Andrew Hemphill]

Regarding the model output for tonight's snow, the more persistent band seems to be further North, streaming through the Clyde-Forth valley. Great news for me by the way, it's already snowing heavily! Long may it continue 

[Nouska]

On more immediate matters, the energy for the weekend storm is departing the Canadian arctic - blob NNE of Newfoundland.

And for the future; coldest extended ECM means seen yet.

  

But not able to work out the pattern from a very blended Z500 mean.

[asjmcguire]

So I had a quick look at the GEFS tonight as I have been over the last few nights because I am interested in seeing how low the pressure for my location will go - and as you would expect the first several days have runs pretty much in agreement with each other until tonight when the GEFS of all 4 runs combined shows this - how can there be any faith in any of the data when Day 0 has so much spread?

Edit: The air pressure for this location is currently 982hPa just to compare to any of the ensembles.....

Edited November 18, 2016 by Andrew Simon Jones
Add actual air pressure reading.

[Mucka]

4 hours ago, Barry95 said:

First it was the middle of November, then the end of November, and now the start of December for the pattern change to significant blocking! Let's hope this isn't a theme of this winter as I have dejavu of this thing happening  from the last couple of winters. A couple of days ago Ian posted about a strong signal towards a more blocked pattern, with GLOSEA and MOGREPS both supporting that. But less than 24 hours later, the signals towards a more blocked pattern had already waned, which goes to show just how hard it is forecasting the weather anymore than a week in the UK. I'm currently not getting excited just yet as all the blocking charts seem to be remaining in the 10-15 day timeframe. The GFS 12z run everyone was getting excited about has already changed  on the 18z. The Northern Hemisphere background does still look much better than last year, but all the good background signals in the world don't gurantee cold/snowy weather for the UK. Until these blocked/cold charts get to at least day 7, theirs no point getting too excited in my opinion.

 

We are getting blocking though, just not in the right places to bring us cold so far (That is always a caveat.) although the next few days are far from mild just maybe not quite cold enough for snow to fall at low levels which is difficult to achieve in the Autumn.

What has been slightly disappointing though, is that blocking has been at the mid latitude rather than higher latitude so far.

Still all to play for and we are in a good position as we head toward winter and still with a chance of something colder before November is out.

The chase can be frustrating but it is also part of the fun.

 

Edited November 18, 2016 by Mucka

[knocker]

morning campers starting with today.

Similar to yesterday although not quite so many vigorous squalls. The east will be the drier area with less showers and after that the SW, Wales and the NW will be prone to more extensive wintry showers but not, as previously mentioned not as blustery as yesterday. N. Ireland and Scotland will get the worst of the weather where the showers will be quite wintry with risk of hail, thunder, etc. Given that the temps will be quite depressed, the more so the further north you go, and still with a fresh westerly breeze, all in all quite unpleasant and definitely a day for Long Johns.

A quick look at the weekend

It looks like the rain will reach Cornwall around 21z Saturday and by 03z Sunday will extend SE of a line Bristol to the Wash. It doesn't look as if conditions will right for any snowfall on the northern flank and the stronger winds should be further south over northern France

.

Further afield

The gfs has the next low swinging in from the SW and is over the SE bu 00z Tuesday and rapidly tracking into the North Sea. Simultaneously the fluid amplification is taking place and by 1800z Wednesday finds the cut off upper low over Iberia with Atlantic HP surging NE. Not unfamiliar territory and again the position of the trough is of some importance because the WAA is to the east and the UK is close to the cold air.warm air divide

From this position the HP and LP tend to revolve slowly clockwise in tandem so that eventually we arrive at the position of HP to the north and an area of low pressure stretching from the SW east. Ergo the UK is under an easterly airstream  So essentially after a cool and wet start to the week it will become drier with temps nearer average although the south could still see some unsettled spells and Scotland could well see some quite nifty frosts in anticyclonic conditions.

Looking further ahead we find the HP retrogressing and energy pincer movements from the NW and the eastern seaboard resulting in mayhem, best left for now.

Edited November 18, 2016 by knocker

[bluearmy]

The ec ops are sinking the Arctic ridge towards our part of the NH in the latter stages of the runs. not an easy fella to model and could be indicative of a general sinking of the pattern over time.  Trying to work out an escape plan for our mid lat high! 

[knocker]

The ecm det. run is not hugely different to the gfs so not much useful to add. Suffice it to say it does tend to end with the HP cell being more influential

[bluearmy]

Found this on twitter showing mid Dec on the ec46

annoyingly the para hasn't updated so I can't contrast and compare with the whole run. My view of the op 46 is it's similar to previous but probably more Atlantic high influence for us through weeks 3 and 4 with the sceuro low anomaly further east than the last few runs post week. Still seasonal though!

[northwestsnow]

32 minutes ago, bluearmy said:

The ec ops are sinking the Arctic ridge towards our part of the NH in the latter stages of the runs. not an easy fella to model and could be indicative of a general sinking of the pattern over time.  Trying to work out an escape plan for our mid lat high! 

Yes me too Blue, looks mainly dry and cold on the ecm 00z but one wonders where we go from the day 10....that said got a lovely dusting of snow this morning, beautiful to see in mid November! 

Edited November 18, 2016 by northwestsnow

[Ali1977]

8 minutes ago, bluearmy said:

Found this on twitter showing mid Dec on the ec46

annoyingly the para hasn't updated so I can't contrast and compare with the whole run. My view of the op 46 is it's similar to previous but probably more Atlantic high influence for us through weeks 3 and 4 with the sceuro low anomaly further east than the last few runs post week. Still seasonal though!

Not a bad position for a high for the UK, by mid Dec we would be dragging in a cold N/NE flow from that. Arctic high forming too so looking good further into Dec.

[NO LONGER POSTING]

Weekend low still not nailed assuming today's runs will try firm up more..

High res starting to come in and there is a lot of difference here is Net weather's take on gusts up to the end of the run totally different to the above 

 

[BLAST FROM THE PAST]

9 hours ago, booferking said:

GFS has been back tracking since yesterday ECM looks to be the form horse.

I thought the GFS was the short wave king.

Still holds the HP further north.

00z messy but brings hurricane force Northerlies at the end with the PV sat over us.....lol that'll be spot on then

[mb018538]

I'll happily take this mornings ECM run - things settling down with a nice cold, crisp winter high.....no Atlantic steam train in sight!  

[carinthian]

10 minutes ago, Surrey said:

Weekend low still not nailed assuming today's runs will try firm up more..

High res starting to come in and there is a lot of difference here is Net weather's take on gusts up to the end of the run totally different to the above 

 

Certainly, nothing nailed. The high res numericals coming into effect will now have to be backed up from the North Atlantic synoptics available. As I can see there is now a formation of a low taking place . You would expect the deepest fall in pressure and track to follow the tight Baroclinic boundary along Polar Jet. Based on that the low should pass the SW of Ireland coast line 300 miles away and head to Brittany before starting its expected curve towards Southern Britain. However, more evidence required for exact track and intensity. It is noted that UKMO model this morning almost drops the secondary low development in to France at 120 hours. So nothing certain from what I can read into.

 C

[Frosty.]

The Gfs 00z is a chilly run,  especially further north and shows next week's trough over the uk getting squeezed, filling and being replaced later next week by high pressure, especially further north and the mid range becomes benign and continues chilly with night frosts and fog but then later it becomes very unsettled from the NW with potential for an Arctic blast..early December could be wintry, it could even happen before that..The models are very interestingly poised.

Edited November 18, 2016 by Frosty.