Model output discussions pm 31/12/15

[SMU]

Morning all

first of all happy new year  

well, its been a pretty ropey couple of days in the world if virtual weather - IE living 4,5,6 days in model land -

for me - relating to the forecast its been good & bad news 

In the post the other day I mentioned changes for 2 things - the atlantic profile & the shortwave over norway -

well the positive news was the energy that was predicted to exit North out of Scandi did infact correct to move westwards towards iceland & more positive heights are identified -

if we look at the UKMO 72 & 96 that energy moving west did change the angle of the cold over europe to a more westerly flow - always a positive for the UK

in terms if the atlantic though - the ridge wasnt sufficient or acute enough to deliver energy surging south of the UK

infact the final position of the jet ended up trending to be angles ENE ( instead of ESE )  so instead of low pressures diving across the Uk they are now projected to move through the uk & will deliver next to nothing in the way of wintryness for the UK except for the scottish hills -

pretty disapointing in an initial set up the promised more -

in terms of future set ups like this & the fact that the UK will of course experience cold weather again we can:

* look for the routes to cold for the UK & see if they manifest in the models & actually deliver

* look at the models & look for the ways the potentially may develop & scupper the cold for the Uk

* forecast endless mild weather & because of the general weather for the UK claim success because of it

 

neither of the latter 2 interest me, its Winter & if we cant all enjoy a bit of the white stuff then were on the wrong forum.

More rubbish weather to come - nothing for most of the populus in the next 10 days which puts us at virtually halfway house for winter 15/16

im already thinking this winter is going to be destined for the bin but hope to proved wrong...

enjoy 

s  

 

[SMU]

Ps

look how close todays GFS is at 108

 

Edited January 2, 2016 by Steve Murr

[Eskimo]

17 minutes ago, Steve Murr said:

im already thinking this winter is going to be destined for the bin but hope to proved wrong...

enjoy 

s  

It was just two days ago you said things would change to colder weather. 48 hours later, you're writing off Winter. 

 

Edited January 2, 2016 by PerfectStorm

[Polar Maritime]

3 minutes ago, PerfectStorm said:

It was just two days ago you said things would change to colder weather. 48 hours later, you're writing off Winter. 

 

It was a punt that went wrong.. Lets keep discussion based around the Model Outputs please, Thanks.

[SMU]

17 minutes ago, PerfectStorm said:

It was just two days ago you said things would change to colder weather. 48 hours later, you're writing off Winter. 

 

 

If we dont get cold on the best opportunity of the winter then it doesnt bode well for the rest of winter bearing in mind theres only really 2 areas of blocking that deliver cold for the UK - scandi & greenland -

6 weeks of winter down & the 1 & only block to the NE has failed to deliver -

so if thats the run rate for the winter then winter is over -

if we had lucked into cold then of course it would be a different story....

[Polar Maritime]

Can we leave the Winters over posts for the relevant threads please, And continue with model discussion. Goodness there's 2 Months of Winter left!.. Thanks.

[Severe Siberian icy blast]

3 minutes ago, Steve Murr said:

 

If we dont get cold on the best opportunity of the winter then it doesnt bode well for the rest of winter bearing in mind theres only really 2 areas of blocking that deliver cold for the UK - scandi & greenland -

6 weeks of winter down & the 1 & only block to the NE has failed to deliver -

so if thats the run rate for the winter then winter is over -

if we had lucked into cold then of course it would be a different story....

Steve even you can't believe what you've just said . The first month of winter rarely delivers for us , it was always gonna be a late burner this one . And it was only you that said an easterly was on the cards , nobody else thought it was gonna happen , I hoped , but never believed . 

We have every chance of a northerly of sorts mid month , and Ian f has always said it was a colder second half and continues to do so . All to play for 

[The PIT]

Well at the from midweek Scotland and the highlands the place to be. Nothing else for the rest of us but more rain and showers. No big storms shown up the GFS although the ECM between T120 and T168 does suggest something more lively. Despite being on the right side of the jet stream cold still not be delivered and the bad news is that this is indicated to move back north again.  Thankfully FI so things may once change to a positive aspect for us.

[knocker]

The anomalies this morning are more or less on the same page. Aleutian LP, Alaskan ridge and trough down the eastern seaboard of the US. Another trough in the eastern Atlantic over the UK. Thus, not unexpectedly, the bouts of wet and windy weather within the westerly regime continue. There will  of course be interludes of quite wintry conditions with snow on the higher ground, particularly up north, as LP systems traverse the country.

In the ext period the ridging over Alaska weakens and with the vortex anchored over N. Canada the trough swings east into the central Atlantic. With the ecm this maintains the WSW flow and a continuation of the unsettled regime but the GFS again has the HP to the south ridging over the UK which backs the flow and would introduce more settled weather. This is something the ops suggested this morning, not for the first time, Clearly the evolution post day ten is not satisfactorily resolved.

 

[Man With Beard]

Another end of the world storm from GFS this morning - this is a MEAN wind speed chart, so hurricane force winds reaching N Devon

Details are changing run by run but potential is there for a serious storm on all op runs this morning. It's looking like February 2014 all over again but with the pattern 200/300 miles further south, so more snow 'opportunities' too especially further north, and as the northerly side of the trough feeds round from the NW.

[Polar Maritime]

A nice N/N/Wly showing for around the 13th on the 6z run. A cold flow dragging in -6/-7 850's across the UK. Ending with -10 uppers touching Scotland.

 

Edited January 2, 2016 by Polar Maritime

[Captain Shortwave]

Indeed PM, the GFS has again found a cold solution for around the 13th/14th onwards. This time an Atlantic low undercuts the developing Atlantic ridge and slides through the channel, northerly follows with perhaps a chance to veer the winds north easterly as the low clears and heights build to the north/north east.

There certainly seems to be a window of opportunity around mid-month again after a spell of unsettled and stormy weather. That said said I would like to see some strengthening anomaly evidence for this from the ensembles and NOAA.

Edited January 2, 2016 by Captain Shortwave

[karyo]

1 minute ago, Polar Maritime said:

A nice N/N/Wly showing for around the 13th on the 6z run.

 

It is something to watch but unfortunately it relies on that flimsy Atlantic ridge. It can easily downgrade with the appearance of n unwanted shortwave.

[The PIT]

Well these charts do keep coming up Deep FI at T200 plus one day one may come off. Whats the verification at T200 plus? Nice charts but don't go down to the bookies on it.

[Day 10]

Very frustrating that we are here with that huge block to the east dangling the usual snow and cold carrot,

 

and voila end up with no block and more wind and rain.

Time to start looking north in the medium term I think. Let's hope the next snow and cold carrot doesn't end up in the Atlantic! I would just be happy to see snow falling outside the window right now nevermind a bitter freeze.

[Polar Maritime]

Heights pushing up into Greenland towards the end of the 6z run with a slack N/E flow. I like the look of that.. As Cap't points out we could well see a cold spell around or just after mid-Month. 

Edited January 2, 2016 by Polar Maritime

[blizzard81]

Well, surprise, surprise! It's raining again. However, one ray of sunshine today so far is the latter stages of the gfs 06z. Not too disimilar to how jan 47 got underway  

[Captain Shortwave]

For the current set up the pattern started off too far east to give us a realistic shot of cold weather.

On new years day the ridge building the high is sitting over France and Germany, several hundred miles east of us. It would have taken a lot of good fortune to develop something decent from here, especially given the persistent strong ow heights to our west and north west which makes backing the high east a tall order.

The GFS whilst we can't take it seriously offers another developing Scandi high at the end of its run. This one however if it verified would be a textbook developing cold spell.

The ridge is build between the Azores and Iberia and stretches up the western side of the UK with cold air covering most of the UK, especially so in souther and eastern areas. At this point the high will be forced north east and the base of the ridge will be eroded away by a pincer movement of the disrupting trough to our west and the deepening cold pool and low heights over most of central/southern Europe. That high would drift north eastwards in the following days to set up a very cold east to north easterly flow with snow for many eastern areas, possibly extending west.

-8C isotherm over SE England, it would only get colder for all from here. We have a finger of 850s as low as -18C over the Baltic states, that could move our way potentially.

No point taking the actual evolution seriously (as in it will happen, this is a chart 16 days away) but the run shows a good example of how a cold pattern can develop from the building of heights eventually to our north east as opposed to the pattern we are in now where a true cold easterly isn't likely to occur.

Edited January 2, 2016 by Captain Shortwave

[knocker]

Digressing but quite interesting

Definition of a sub-trop jet off 1 loop. Current WV is a perfect example.. Polar jet diving down now as well http://mp1.met.psu.edu/~fxg1/SAT_US/animwv.html …

[The PIT]

Surprised nobodies posted the beast from the east

 

 

Edited January 2, 2016 by The PIT

[blizzard81]

Just now, The PIT said:

Surprised nobodies posted the beast from the east

 

 

This has been discussed this morning - see posts above.

[carinthian]

This is about as good a flow as it gets for snow showers in Cheshire, South Manchester and Peak District. Of course if it ever came off !

 C

[karlos1983]

3 minutes ago, The PIT said:

Surprised nobodies posted the beast from the east

 

 

Not really the beast we are after, more of its lame lesser cousin. Which is pretty unlikely to verify, very weak ridge that is certain to get shoved east as is usual with the GFS imo 

[BLAST FROM THE PAST]

Will probably post longer after the 12s but I can't understand the despondency. Yes we fail on the direct hit but the chances remain of more shots at cold, and I don't think they will go away either.  We haven't seen the well vaunted pressure rise from the SW have we...

BFTP

[Yarmy]

10 minutes ago, karlos1983 said:

Not really the beast we are after, more of its lame lesser cousin. Which is pretty unlikely to verify, very weak ridge that is certain to get shoved east as is usual with the GFS imo 

I realise it's arguing about how many angels can dance on the head of a pin, but the high strengthens to that point and, as the Captain say, even with a shove east you end up with a genuine Scandi high and an ever colder flow into western Europe, and potentially a battleground over the UK.

Anyway in the short term, how many runs actually showed our phantom Easterly penetrating the UK? One T144 12z from the UKMO, and a handful of GEFS perturbations maybe? 

Edited January 2, 2016 by Yarmy