Model Output Discussions 12z 01/09/2016

[phil nw.]

Ok guys let's get back on track and discuss the charts-if you want banter then use the correct threads or pm-ta.

[Dancerwithwings]

The 12z UKMO looking decidedly unsettled come Friday, but still a lot to play for even at 144h, the last chart 

[Grimers]

Let's just say it's looking quite cool for the time of year. Many models continuing with an E wind through the next 10 days with temperatures below average. As others have pointed out, there's a possibility of a deep low sitting to the SW of the UK on Friday. If only this was in the middle of Winter! That would be good!

Edited October 16, 2016 by Grimers

[knocker]

The GFS has the Canadian train getting into motion next week resulting in a general area of surface low pressure to the west and south west and some very nifty WAA if of course it verified, If I may borrow a phrase from the mafia if this was only a couple of months hence then roast chestnuts would be quite apt.

Edited October 8, 2016 by knocker

[knocker]

The ecm is not dissimilar to the GFS for next week although obviously the detail will vary.

[Frosty.]

The Ecm 12z looks particularly chilly around the middle of next week with strengthening ESEly winds as a trough pushing up from the southwest bumps up against the scandi high and tightens the isobars and the high is forced further north before drifting northwest towards Iceland / Greenland. It shows our weather gradually becoming more unsettled later next week from the SW but also milder / warmer as winds swing around to a SWly / Sly and the s / se briefly imports some warm air from france and generally beyond midweek the temperatures across the uk recover somewhat but especially for the south.

[Grimers]

The chilly spell that has been over most parts of the UK for several days continues on into next week as both the ECM model and the GFS model show. However, the ECM shows a somewhat deep low just to the WSW of Cornwall possibly bringing strong SE winds to W parts of the UK.

However, surprisingly the GFS model predicts the low to be weaker but still in a similar position.

It seems to be the only interesting day next week apart from the persistently chilly NE wind.

Edited October 16, 2016 by Grimers

[bluearmy]

Whilst there is some sniffing around the Atlantic trough getting far enough east and becoming sustained enough to bring a mean southerly component to the flow, the eps post day 10 continue to paint high anomolys  to the wnw and low to the ese

as a result, temps remain on the low side of average post any temporary recovery to average/slightly above. 

 

[shaky]

Is it me or since the really warm 00z runs from this morning theres seems to be an increase in heights across iceland and greenland and more undercutting of low pressures into the continent continuing the cool temps!!wouldnt be surprised if theres is no plume at all by tomorrow mornings runs!!

[blizzard81]

1 minute ago, shaky said:

Is it me or since the really warm 00z runs from this morning theres seems to be an increase in heights across iceland and greenland and more undercutting of low pressures into the continent continuing the cool temps!!wouldnt be surprised if theres is no plume at all by tomorrow mornings runs!!

You are right, that has been the theme of the 12z runs. They may revert back to to 00z runs of yesterday, they may not. What I will say is the models will struggle as these are not your typical autumn zonal synoptics :-o

[knocker]

Today and Monday

The upper low to the east continues to be the main influence as it drifts south thus a continuation of the northerly/easterly flow. Broken cloud for much of the country but more cloudy along North Sea coasts with some showers. Quite cool in these areas as well otherwise quite pleasant in the relatively light winds.

The rest of the week courtesy of the GFS.

Although the conduit for energy remains the the precise orientation of the resulting trough does strongly influence where the surface features set up and bt midweek this is further to the south west than previously thus leaving the UK under the influence of the HP to the NE and in an easterly wind component.

Things then begin to unravel as the conduit adjusts east and initiates low pressure domination over the UK for the weekend bringing some quite unsettled weather, This is pretty knife edge stuff and just slight adjustments to the upper pattern makes some large differences to the surface analysis and with tropical storms moving north along the eastern seaboard a continuation of a watching brief is probably the wisest move for the time being.

Absolutely n point in looking further ahead at this stage but just to note it does move the Scandinavian HP away to the NE in a quite active upper air pattern.

Edited October 9, 2016 by knocker

[Man With Beard]

The ECM this morning a little on its own in reviving the summer, as other runs plonk a great big low over us by T144. The latter allow northern blocking to remain, the ECM crushes it. Any guidance from the GEFS? Not this morning, it's like an old radio that's lost its frequency.

[knocker]

Well there is some guidance MWB

It's tending to keep positive anomalies in the Iceland area whilst declining the Scandinavian block and thus returning the upper flow to the westerly quadrant.and perhaps with temps nudging a little above average.

[Man With Beard]

18 minutes ago, knocker said:

Well there is some guidance MWB

It's tending to keep positive anomalies in the Iceland area whilst declining the Scandinavian block and thus returning the upper flow to the westerly quadrant.and perhaps with temps nudging a little above average.

Looking at the individual clustering at D10

http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=1&ech=240

heights are all over the place. Some runs bring back the Azores HP, some build heights over Europe and a few maintain a block to the north. Even at T168, there is a big split between runs keeping the trough west of the UK or over the top of us. I'd say the mean chart is of limited use in such circumstances?

Incidentally, the GEFS end of month signal for a decent east-based vortex is still there - but what's changed is an increased appetite for a Canada-Greenland based one too - not overwhelming and there's still a chance for a cold shot at the UK further down the line, but the tendency is growing, which would make it more difficult to get Arctic winds to filter this far south.

Edited October 9, 2016 by Man With Beard

[knocker]

3 minutes ago, Man With Beard said:

Looking at the individual clustering at D10

http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=1&ech=240

heights are all over the place. Some runs bring back the Azores HP, some build heights over Europe and a few maintain a block to the north. Even at T168, there is a big split between runs keeping the trough west of the UK or over the top of us. I'd say the mean chart is of limited use in such circumstances?

I certainly wouldn't bet the house on one run and without support from the ecm but one has to try and get a handle on the drift. Having said that it is why I haven't been looking further than next weekend and even that's not anywhere near a done deal.

[Grimers]

There's a bit of a difference in the ECMWF model, UKMO model and GFS model this morning.

The ECMWF model shows a weaker low to the W of Ireland introducing less of an E breeze.

However, the UKMO model shows a low to the S of SW England introducing an E breeze making it feel chilly in exposure.

However, unlike the ECMWF model and UKMO model, the GFS model shows a somewhat weaker low over SW England instead of in the Atlantic approaches.

There's obviously disagreement in the models, but seen as the low is not very significant, there's not a lot to be concerned about.

Edited October 14, 2016 by Grimers

[Frosty.]

19 minutes ago, knocker said:

 that is why I haven't been looking further than next weekend and even that's not anywhere near a done deal.

Yesterday you were looking at January as it showed above average temps and calling it realistic!

[Man With Beard]

13 minutes ago, Frosty. said:

Yesterday you were looking at January as it showed above average temps and calling it realistic!

sorry off topic mods - I think that was Sidney posting not Knocker! or maybe a little joke at the expense of OTT cold rampers.

[Frosty.]

On 06/10/2016 at 15:57, Man With Beard said:

 

Two months ahead of my expected schedule, I declare the winter chase 2016/17 open!

Speaking of OTT cold rampers!

 

Edited October 9, 2016 by Frosty.

[Man With Beard]

11 minutes ago, Frosty. said:

Speaking of OTT cold rampers!

 

Going by the runs of the last two days, I'm almost ready to close it again still a chance that heights will be strong enough towards Greenland to allow an end-of-month cold plunge but the window would seem to be closing on that one.

 

[Frosty.]

12 minutes ago, Man With Beard said:

 still a chance that heights will be strong enough towards Greenland to allow an end-of-month cold plunge but the window would seem to be closing on that one.

 

It's no cause for concern MWB, we have 3 months of winter to look forward to, from one cold ramper to another

Edited October 9, 2016 by Frosty.

[MR EXTREMES]

yes the other days i was out of the blocks like a scared greyhound,

but knocker was on the money!

when he suggested the blocking heights would slowly decline into a more seasonal october flow.

not seeing to much interest for the cold crew still some chilly ish weather until lows approach with perhaps brief upper air warmth then back to more normal!.

 

but becoming unsettled.

and i admit there has been many october nov blocks,

that suggested retrogression to greenland then completely decline,

 so my garden path is alot longer than most lol.

next hype from me will be when im above 80% certain on the pattern.

Edited October 9, 2016 by MR EXTREMES

[bobbydog]

i wouldn't worry about short term variations for now, tentative good news is, from ian ferguson, the EC seasonal is showing HP anomalies over Greenland/N-NW of the UK. from november right through to february!

back to now, how will the track of TS Matthew affect the models now it is predicted to travel east into the Atlantic rather than curve back to the Bahamas?

[Grimers]

On 10/9/2016 at 11:56, bobbydog said:

i wouldn't worry about short term variations for now, tentative good news is, from ian ferguson, the EC seasonal is showing HP anomalies over Greenland/N-NW of the UK. from november right through to february!

So, I would presume this is suggesting a colder than average Winter then? A high to the N and a low to the S mean E winds...

Edited October 14, 2016 by Grimers

[knocker]

5 minutes ago, bobbydog said:

i wouldn't worry about short term variations for now, tentative good news is, from ian ferguson, the EC seasonal is showing HP anomalies over Greenland/N-NW of the UK. from november right through to february!

back to now, how will the track of TS Matthew affect the models now it is predicted to travel east into the Atlantic rather than curve back to the Bahamas?

 

He also mentioned low pressure to the south west so i can envisage some warm south westerly zephyrs. He also added the caveat best wait for the November outputs.

Anyway back to the here and now with Mathew and Nicole