Model Output Discussion 1200 hrs 15/11/14

[MR EXTREMES]

not to bad in the south frost perhaps fog looks like scotland could be a bit wet and windy.

north south split looks likely nothing terribly exciting as matt suggested in the strat thread and others i think jan could be the month were cold sets in.

 

if and its a big IF  the strat gets blow torched but who knows!

 

tbh been a rather static picture for awhile so perhaps we need the zonal train to start again.

 

the jet dont look terrible though after powering up direct at northern uk it does seem to weaken but has it done enough to allow the zonal push in far enough......

Edited November 24, 2014 by emotional rollercoaster

[shaky]

Very interesting parallel run at 138 hours! ! Stronger arctic high amd everything further west aswell!! Ukmo has an easterly in already at 96 hours!

[MR EXTREMES]

could we get a arctic flow from here 2009 2010 heights building in the alantic with lows dropping into scandi perhaps a ne flow into december.

just an idea 

 

ukmo has a brief easterly/south easterly but not sustained 

 

gfs certainly snow even at lower levels for the north and wales on the mountains and hills not the worst run.

nothing mild here at least snow will be in the forecast if this run was to be correct.

to be honest a pretty nice looking run bit messy but looks much nicer from the hemispheric view.

ukmo is rather a let down which throws the gfs under the bus as it is a different evolution to the gfs although the ukmo would have frosty more settled to the southern half but north very windy and wet but snow could still feature for the north in the coming week or so in there longer term outlook.

 

i think us in the south will have to wait awhile yet.

Edited November 24, 2014 by emotional rollercoaster

[MR EXTREMES]

what is rather unsettling is the bigger part of the vortex lobe is on or around the greenland area always makes be a little nervous for the up and coming winter.

[nick sussex]

I think I'll keep my mouth shut in future. The GFS is progressive, , the GFS P is caught in between two minds if you're going to get the cross polar flow you need to see more trough disruption at T144hrs, effectively here the Arctic high is trying to force the jet south.

 

We really want an either or scenario, either low heights run ne and allow  high pressure further north or the Arctic high forces the jet so far south that the incoming troughing at T144hrs disrupts to the sw of the UK.

 

The GFS P is now doing neither, so effectively you end up with troughing stuck to the north but not far enough north and no easterly. I'm glad I didn't go on a ballon ride today, it surely would have hit an electrical pylon!

 

So the Arctic high turned up teased, trashed the easterly and then weakened! Off now to hit my head against a brick wall!

Edited November 24, 2014 by nick sussex

[summer blizzard]

GFS turns on the engine in FI but once again both runs have high pressure build..

 

 

[cold snap]

To be honest ,the Atlantic not been cut off it any output I've seen

Yes There's a block to are east ,but are main thrust of operations is still to strong .

Atlantic still operating the weather ,different to last year For sure .but any serious trend Change looks unlikely

[blizzard81]

The trend for tonight's 12z runs so far are for the atlantic to gain the upper hand and this ties in with the Meto forecast. I fully expect the 12z ECM to go the same way and therefore look quite a lot different to this mornings run. I knew it was too good to be true!

[Summer Sun]

GEM offers the chance of some snow in the SE for a time next week

 

 

What does the purple hash lines mean? Freezing rain?

 

[carinthian]

To be honest ,the Atlantic not been cut off it any output I've seen

Yes There's a block to are east ,but are main thrust of operations is still to strong .

Atlantic still operating the weather ,different to last year For sure .but any serious trend Change looks unlikely

Yes, certainly the lows are stalling now in the vicinity of the British Isles. However, the Atlantic is not breaking down the Russian high. The latest mid-day runs from GFS and UKMO continue the theme of sinking that high, that was the case 14 days ago but its still there amassing a cold entrenchment under snow cover. Pointless looking beyond 5 days. Temperatures will rise somewhat under a warmer feed with less rainfall than recently but a colder drift looks likely at weekend in the South. Beyond that, I think changes will still occur in the daily models with a increasing hint to a colder December,

C

[gottolovethisweather]

I think I'll keep my mouth shut in future. The GFS is progressive, , the GFS P is caught in between two minds if you're going to get the cross polar flow you need to see more trough disruption at T144hrs, effectively here the Arctic high is trying to force the jet south.

 

 

 

Indeed Nick, I wouldn't look beyond Saturday now as until we know how the NH Jetstream is going to behave the evolving UK weather pattern could go anywhere beyond this. According to the current state of play, there is a split Jet out in Mid-Atlantic at t+117 and this being the first I've seen of it, from within this latest run, I'm not so sure about this new trend.  

 

 

Back on the 18th November (my last comprehensive NH Jet posting), it was projected to act in the following manner by 12pm on 1st December, which is only a couple of days on, ie. next Monday.

 

 

Now, the uncertainty of the overall NH pattern hints at the following being likely at 12pm on 1st December.

 

 

 

The above chart is only at t+168 hours, but I'll believe it when I see it.  :nonono:CHALK AND CHEESE.

 

Incidentally prior to the above timeframes, some warm uppers brought into the mix during next weekend, look a possibility at this long-range before being ushered away by a blast of PM air come t+168 hours or thereabouts. Thereafter, deep into the first week of December we get a stand-off between an Atlantic reload (as predicted by the seeming GFS default pattern) or a polar mix influence via the East and Northeast flow. The trend for the start of December being largely dry and fairly chilly by day is a fairly strong one for now. All we need is some further cross-model agreement regarding these timeframes and a bit of daily inter and intra-run consensus before I firmly jump on board with the likelihood of either scenario, be it with the UK in no man's land or under an Atlantic influence. By the middle to end of this week we will know our fate, for sure. 

Edited November 24, 2014 by gottolovethisweather

[492]

00Z ECM continues the theme of expanding the area of low pressure to the south of the UK which has the effect of propping up the ridge and allowing cold air to flood over the UK from europe in a stiff northeasterly. 

http://www.meteociel.fr/modeles/ecmwf.php

 

!2Z UKMO T+ 96 to T+144 has come into line with ECM indicating that the trough diving SE in the Atlantic disrupts and cuts off with a sizeable area of low pressure moving east across Spain resulting in an easterly feed across the south of the UK. If correct colder air will eventually be drawn in from further east.

http://www.meteociel.com/modeles/ukmo2.php?ech=6&carte=1021

[Captain Shortwave]

Still very unconvinced on any cold easterly developing. People have mentioned the one starting from Friday, to be honest the predicted temperatures down here are 12-14C despite the wind being from the east so little joy in that department (btw these are metoffice/BBC predictions)

It all seems to be on the depth of the low over Iberia, a deeper low might support an easterly just, but any downgrades in the strength and we will end up with high pressure over the UK with light and variable winds. The GEMs shortwave development looks dubious too as it cuts through the Azores high to bring a minute pocket of cold air from SE Europe to the UK.

Overall I am feeling no different from this morning. More settled weather with frosty nights would be my call beyond this coming weekend. Though plenty of time for change.

After a brief cool and settled spell. Round 9 million between the Atlantic and eastern European block 

 

Lastly at the end of week 2, some hints of something cooler developing again with low heights beginning to sink south east through the UK and into Europe. Worth keeping an eye on.

Edited November 24, 2014 by Captain shortwave

[Nick F]

The trend for tonight's 12z runs so far are for the atlantic to gain the upper hand and this ties in with the Meto forecast. I fully expect the 12z ECM to go the same way and therefore look quite a lot different to this mornings run. I knew it was too good to be true!

 

Don't bet on it, wouldn't guarantee the Atlantic will gain the upper hand past day 6 when GFS op goes rampant with it. Personally think the GFS might be too progressive with eroding the mid-latitude ridge that links Azores and Russian highs across the UK this weekend.

 

About 50% 12z GEFS members going for mid-latiitude HP holding on across the UK by t+180 (next Tuesday):

 

http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=1&ech=180

Edited November 24, 2014 by Nick F

[picog]

What does the purple hash lines mean? Freezing rain?

I think so. "Verglas" means black ice.

Edited November 24, 2014 by picog

[nick sussex]

After my earlier tirade I've calmed down now!

 

Tonights NAVGEM illustrates what you want to happen if the Arctic high is going to play a prominent role, you get more trough disruption around T144hrs.

 

Versus a halfhearted attempt on the GFS P.

[Timmytour]

You can go back to the start of this thread and read plenty of thoughts about what the trends are from D6.

The only thing I can read from the models is continuing stalemate. A place in no man's land between the Atlantic and the East which will provide us with a continuing fare of showers and longer periods of rain interspersed with the occasional chilly night or two. In a week's time it might be possible to be more positive about one outcome or the other dominating, but I've seen too many indicators of the Atlantic breaking through after D6 onwards over the past couple of weeks to believe that the situation is really going to resolve itself one way or the other this time.

For me, wednesday represents the next potential time for a gamechanger.....will the rain currently showing make it through and away from the South East as quickly as is forecast?

I suspect it may linger and cause problems and that may indicate the block to the east asserting itself.....but it's waiting on time to tell as, as has been the case for much of this month!

[nick sussex]

The ECM thankfully doesn't do an Arctic high tease and saves my sanity.

 

So far it looks similar to this mornings output, don't get me wrong an Arctic high can be a good thing but in the current set up if it doesn't deliver the NAVGEM solution then you're stuck with the GFS P middle ground solution.

 

I think we need to buy some time whilst the PV decides what it wants to do, we might yet get to some much more interesting output but in the meantime at least might get some more seasonal temps with a colder flow off mainland Europe.

[Captain Shortwave]

Mixed feelings about the ECM tonight

That chart pretty much sees us heading back to where we are now as cold air from Greenland breaches the ridge and dives towards Iberia.

Or maybe not

Week 2 spells wet, cool and miserable really as neither the Atlantic or high pressure gets a foothold and results in a cyclonic north easterly with bands of rain spinning around.

Edited November 24, 2014 by Captain shortwave

[gottolovethisweather]

Mixed feelings about the ECM tonight

That chart pretty much sees us heading back to where we are now as cold air from Greenland breaches the ridge and dives towards Iberia.

 

Yes No man's land by then is looking the most viable option right now but the bigger NH view ain't half bad. The Atlantic doesn't get a look in (temporarily it could at D5 for parts NW) and also, the continent will have also cooled down nicely by next Monday. No deep cold and none forecast but certainly looking ever more like a case of EYES North East and East come December after a few settled cool/cold days to kick December off. BANK! 

Edited November 24, 2014 by gottolovethisweather

[Cloud 10]

The ECM thankfully doesn't do an Arctic high tease and saves my sanity.

 

So far it looks similar to this mornings output, don't get me wrong an Arctic high can be a good thing but in the current set up if it doesn't deliver the NAVGEM solution then you're stuck with the GFS P middle ground solution.

 

I think we need to buy some time whilst the PV decides what it wants to do, we might yet get to some much more interesting output but in the meantime at least might get some more seasonal temps with a colder flow off mainland Europe.

 

Here's the JMA at 192 hrs to calm your fevered brow.....  

 

[Summer Sun]

If ECM is correct it would turn cooler early next week with winds coming in from the east / north east

 

 

A more seasonal start to December if nothing else its a big improvement on 12 months ago

 

Edited November 24, 2014 by Summer Sun

[nick sussex]

It doesn't matter how strong the PV is as long as you maintain low pressure over southern Europe. This is strongly correlated with cold weather for the UK, at least December starts off on a seasonal note so although no fireworks on the ECM its okay IMO.

[nick sussex]

Here's the JMA at 192 hrs to calm your fevered brow.....  

 

JN192-21.GIFJN192-7.GIF

Lol! Yes we're left in this difficult position because on one hand the Arctic high could just flatter to deceive like the GFS P, or it could help deliver the JMA/NAVGEM solutions.

 

Once the ECM postage stamps come out we'll be able to see how many have the similar set up at T120hrs to the JMA/NAVGEM.

[blizzard81]

Lol! Yes we're left in this difficult position because on one hand the Arctic high could just flatter to deceive like the GFS P, or it could help deliver the JMA/NAVGEM solutions.

 

Once the ECM postage stamps come out we'll be able to see how many have the similar set up at T120hrs to the JMA/NAVGEM.

These two models are the cannon fodder though Nick!