Model Output Discussions 12z 01/09/2016

[Mapantz]

9 minutes ago, ANYWEATHER said:

The black arrow shows ex Hurricane Matthew

Nicole has had a sex change?!

[I remember Atlantic 252]

17 minutes ago, ANYWEATHER said:

Hello Everyone! A general consensus from the ecm and gfs  from now to Tuesday is for unsettled conditions . A ridge builds ahead of ex hurricane Matthew and with cold air in situ a real mix of frost mist and fog  After that some wild swings thanks to Matthew !!! The black arrow shows ex Hurricane Matthew

 

1 hour ago, Matthew Wilson said:

Warm air blasted into the arctic by the ECM by ex hurricane Nicole. Hopefully this isn't the joker in the pack when the hurricane season ends.

Was going to post, is it Matthew or Nicole???????

[Matthew.]

4 minutes ago, I remember Atlantic 252 said:

 

Was going to post, is it Matthew or Nicole???????

I thought it was Nicole from Knockers post earlier

 

Edited October 13, 2016 by Matthew Wilson

[ANYWEATHER]

Sorry for the confusion Blasted Hurricanes.  Nicole  rather than Matthew How dare they confuse us

Edited October 13, 2016 by ANYWEATHER

[knocker]

I was interested to see how the EPS developed this over the next five days.

For the next couple of days little change and from then until the end of the run the trough weakens and very strong anomalous positive heights edge west to be in the Iceland area accompanied by slight ridging from the Azores. This is not mid Atlantic amplification but it's not far off of it and we are still in ball park of positive height rises. This scenario would indicate surface HP stretching from the Azores in the south west through the UK to strong ridging in the North Sea with a SWS flow over the UK This of course will not be the situation in a few days time but the models are certainly playing around with high pressure in the vicinity of the UK.

[Frosty.]

Tonight's Ecm 12z ensemble mean paints an increasingly pretty picture next week as the trough at the start of next week is quickly sent packing by high pressure building in from the southwest and settling things down with daytime temps becoming pleasant during the second half of next week with chilly nights where skies clear but mist and fog forming. By T+240 there is a trough knocking on the door just to the west but the east and southeast would still be fine.

[mb018538]

A bit of a fly in the ointment today that wasn't picked up in the last couple of days - Nicole is buckling the jet in such a way that it is allowing low pressure to slide down the eastern half of the UK



As such, the GFS never really settles down. UKMO shows something similar too - so west could again be best if this plays out in this manner.

[Ali1977]

Day 14 average pressure chart from the GFS ENS, the main thing that jumps out is a distinct lack of any PV .

[knocker]

The transition to a showery and warmer (relatively) for the weekend starts later today with the approach of low pressure and fronts from the south west. Meanwhile a rather cloudy cool day for most and particularly foul for the eastern half of Scotland with some heavy showers, perhaps thundery, and feeling decidedly chilly.

low pressure just to west over the weekend tracks north and establishes a conduit to large area of LP over northern Canada which allows the next upper trough to shoot SE across the UK on Tuesday bringing some wet and windy weather with it.

But here things begin to get interesting. The trough sticks over Germany and intensifies and meanwhile Nicole has tracked to a position SE of Greenland where a deep pool of cold air resides and HP has ridged to the west of the UK. Whether Nicole has anything do with the turn of events is above my pay grade I'm afraid.

From this position it's all down hill with a vigorous cold upper trough emerging from Greenland to effect all of the mid Atlantic moving slowly east with the potential to bring some very inclement weather to the UK by the weekend.

 

Edited October 14, 2016 by knocker

[bluearmy]

Latest ec46 is a departure from previous runs in that the mean height anomoly through much of November (relevant to us ) is a slightly raised European one.  Gone are the high anomolys just to our north and northwest and mean uppers for the month showing above average for us.

have to wait until tuesday morning to see if this is going to become the form horse now it has gone back to a more traditional aspect. 

I haven't looked in any detail at what happens on a hemispheric basis so assessing what the run might mean looking further ahead into winter proper has no comments from me

[SMU]

The trend of the GFS ensembles from day 10 - 16 is to drop the vortex into siberia -- which has been suggested for a few days now-

many many runs depict a strong 2 wave pattern - with this being the cherry on the somewhat icy cake - 

I may go & check the October AO date record today - it could be under threat--

S

[mb018538]

A VERY interesting ECM run this morning, developing yet another Scandi high, with an Azores low. Anything but zonal, that's for sure:

[Ali1977]

Not great news that the EC46 has swung away from high lat blocking - lets hope it reverts back next run!!

[knocker]

The ecm has Nicole tracking north and phasing in with the Greenland trough next Weds with ridging in the eastern Atlantic. This initiates the formation of the next trough which is negatively tilted and runs SE to dominate the eastern Atlantic. Because of the tilt the jet and upper flow run around the southern quadrant of the trough which produces a quite a warm SW flow over the UK, albeit possibly quite wet. and hopefully keeps the much colder of the trough to the west. Aided and abetted by HP still being very strong to the NE

 

Edited October 14, 2016 by knocker

[Frosty.]

According to the Gfs 00z the main thing we will notice this weekend and the start of next week is how mild it will become as we will be within the circulation of  low pressure to the southwest pumping tropical maritime air northwards across the uk with temps in the south reaching 17/18c and widely 14/16c...so today is the last of the chilly feeling days at least for England and Wales, having said that, the south will be feeling milder today than recent days with 14/15c. It does gradually become cooler again next tues / wed from the northwest with the southeast holding on to the mild air for longest and we will all see some rain and showers during this period but with pleasant sunshine too.

Edited October 14, 2016 by Frosty.

[A.J]

some off topic posts by the usual suspects removed from the thread, please stay on topic and discuss the models.....thanks

[terrier]

45 minutes ago, Ali1977 said:

Not great news that the EC46 has swung away from high lat blocking - lets hope it reverts back next run!!

Yes but as we all know with models for our little island they will always revert to the default pattern. But as you say it isn't a great sign that it moves away from the high latitude blocking. Abit nearer to the here and now and the gfs looks rather pleasant into next week with a return to some milder air moving in. 

[Midlands Ice Age]

1 hour ago, Steve Murr said:

The trend of the GFS ensembles from day 10 - 16 is to drop the vortex into siberia -- which has been suggested for a few days now-

many many runs depict a strong 2 wave pattern - with this being the cherry on the somewhat icy cake - 

I may go & check the October AO date record today - it could be under threat--

S

Steve

This will extend the SAI very much westwards if this is anything like verified.

Could  it be there is a connection between these 2 different sets of observations?

MIA

[SMU]

30 minutes ago, Midlands Ice Age said:

Steve

This will extend the SAI very much westwards if this is anything like verified.

Could  it be there is a connection between these 2 different sets of observations?

MIA

Hi

I think its more cause & effect - that then helps become self perpetuating-

Significantly low ice > Tamar region high geopotential heights > Southward & westward SAI development > Winter feedbacks supporting -AO 

This feedback isnt the MAIN driver of the weather - ENSO / Strat profiles can overule this - however when the strat is condusive & the ENSO isnt super + it certainly helps-

S

[Grimers]

The GFS model and the ECMWF model show a low to the SW of Ireland bringing light SE winds and cool temperatures to all parts of the UK tomorrow.

   

 

 

 

Edited October 16, 2016 by Grimers

[Frosty.]

The GEFS 00z mean looks settled nationwide from around next midweek onwards with largely very pleasant surface conditions with good sunny spells and mild daytime temps offset by some chilly nights with mist and fog patches but really nothing to grumble about, it's a benign nice extended outlook judging by this.

[Nick F]

IMO Hurricane Nicole will be instrumental in rebuilding that H500 anomaly over Scandi/Barents as indicated by the 00z GEFS and EPS H500 anomaly charts into the extended range

The tropical warmth wrapped in Nicole is indicated to be transported poleward NE toward Norwegian Sea in the mid-levels - which will rebuild the block and cause troughing pushing east across the Atlantic to disrupt SE once the block re-intensifies to the NE:

It appears high latitude blocking will be with us until the end of October, 00z GEFS even hints at retrograde of the anomaly, whether it hangs on into November, when the air sources to the east will get progressively colder, remains to be seen. But the persistence of the blocking signal to the NE certainly an early positive sign for coldies as we head into the cold season.

[Frosty.]

The GEM 00z shows a surprisingly unsettled outlook throughout next week and later in the run becomes unseasonably warm but windy thanks to a deepening low to the southwest.

[carinthian]

On 12/10/2016 at 14:06, carinthian said:

The main feature to notice here in 10 days is the prolonged establishment of the block to the east with increasingly cold surface flow by this time. Looks like a repeat phase of narrow trough distruption. Jet stream pattern remains fragmented and meridional rather than full frontal zonal, so eventual placement of any troughing will be hard to locate at this time stage.

 C

Glad to read Nick F latest positive thoughts this morning on this scenario. Really, quite a strong persistent block for the time of season,aided and better by the strong warm air affected poleward . As he hints come November the continental flow will turn markedly colder. Positive picture for lovers of cold emerging.

C

 

 

[Grimers]

36 minutes ago, carinthian said:

Glad to read Nick F latest positive thoughts this morning on this scenario. Really, quite a strong persistent block for the time of season,aided and better by the strong warm air affected poleward . As he hints come November the continental flow will turn markedly colder. Positive picture for lovers of cold emerging.

C

I agree! I feel the EC seasonal output may well be correct this year, but you never know what will happen at this stage.

Edited October 14, 2016 by Grimers