Model Output Discussions 12z 01/06/2017

[Frosty.]

Summer looks like making a comeback next week..in the nick of time!..glad I didn't throw the towel in now

The Gefs 00z mean looks increasingly good beyond this week

Edited August 14, 2017 by Frosty.

[Summer Sun]

GFS and UKMO couldn't be more different at D7

[I remember Atlantic 252]

3 minutes ago, Frosty. said:

Summer looks like making a comeback next week..in the nick of time!..glad I didn't throw the towel in now

Not really on ECM, just the usual S/SE, my location and many northern areas looking not much better

[stodge]

Morning all

Looking at the models this morning, I'm struck by the influence of events to the south rather than the south west. A lot of people are looking at the Azores HP but perhaps they should be looking at the African/Iberian LP which GFS in particular makes a lot of trying to bring it further north. The movement of this potentially thundery area forces the HP at first north over us and then splits the HP leaving us under the influence of the trough with heights shunted to the north.

GEM phases the Iberian and Atlantic LPs into a single feature as a mid-Atlantic ridge builds behind it at T+204:

GFS doesn't quite do the same but the trough from the south is hugely influential as it shunts the HP north:

ECM does nothing with this at all and is again out of kilter with the American/Canadian models.

The role of the trough to the south is significant as it either keeps the HP to the north or prevents it building across from the south west leaving us in the trough trap as I termed it the other day between the trough to the north or north west and the thundery trough to the south.

[stodge]

2 hours ago, Summer Sun said:

GFS and UKMO couldn't be more different at D7

The key difference is how the two models deal with Tropical Storm Gert. I would guess UKMO moves it through quicker absorbing it into the LP which then comes over the UK as illustrated. With GFS it's slower and the LP is slowed allowing HP to develop to the east.

[mb018538]

Still a hell of a lot to be resolved - but I think the general picture is probably the best its been for a while. The GFS is very consistent and bullish in returning high pressure to the UK in some way - it just depends whether its dry and pleasant, or dry and warm/hot. Tropical disturbances wreaking havoc as usual at this time of year.

[Man With Beard]

Bank holiday weather already within range of ensembles. Both GEFS and ECM favouring settled scenarios over unsettled ones at the moment.

GEFS clusters for 27 August: http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=euro&MODELL=gefs&MODELLTYP=2&BASE=-&VAR=cz50&HH=348&ARCHIV=0&ZOOM=0&PERIOD=&WMO=

ECM clusters:

We shall see how things unfold!

[Summer Sun]

Sunday is shaping up to be a decent day at this stage

[knocker]

Members of the jury I would, if I may, just like to draw your attention to the point i attempted to make yesterday about treating individual runs with great care when looking too far ahead in patterns that are very fluid. An illustration of this for next week from the the gfs 06 and 12

Which at day ten is leading to a cold plunge

 

Edited August 14, 2017 by knocker

[Frosty.]

The Ecm 12z is trying its best to spoil what little remains of summer 2017 with trough / ridge / trough..etc..high pressure just can't build in properly..always seems to be day 10 when there are better signs upstream! I think the best way of describing this run politely is generally changeable with occasional drier, brighter days, mainly across the s / se but also unsettled at times, especially further n / nw.

I really want to see a warm / very warm settled end to this summer as I'm sure most of us do but there's no sign of it on this evidence. This morning I was singing the praises of the Gefs mean in the mid / longer range but unless all the models are on-board, especially the ecm, it doesn't count for anything!

Edited August 14, 2017 by Frosty.

[mb018538]

I wouldn't count anything in or out for a couple of days, until the tropical feature is resolved properly. You'd favour the more unsettled ukmo and ecm solution, but let's just see what happens.

[Frosty.]

Tonight's  Ecm 12z ensemble mean really perks up by day's 9 and 10 with pressure rising across the uk..

[Allseasons-Si]

I am really liking the 6-10 and the 8-14 day from noaa if it is correct,nice southerly plumes on them i would of thought

now come on op's play catch up

[Fourty Point Three Degrees]

in some of these GFS runs I'm seeing HP centred right over the UK but why are temps so idle? Showing maxes of around 19 to 21C - surely with HP splattered right across us in August maxes should be around 26 to 30c?

[knocker]

At the risk of sounding very much like a stuck record the anomalies last evening once more show little inclination of significant change in the next 14 days. Having said that in the latter period there is room for some disagreement with the trough to the NW taking a more friendly alignment and a weakening westerly flow perhaps the Azores could become a tad more influential, although probably only in the southern half of the UK. Temps still around average generally, perhaps a little below.

In the ten day time frame a not unfamiliar pattern although an upper low has appeared over Greenland courtesy it would seem, of the Canadian ridge migrating a north into the Arctic and a creating a pathway from the Alaskan trough. Anyway still a quite strong westerly upper flow thus changeable/unsettled weather continuing over the UK and once more it will be down to the det runs to sort the detail of the continuing interaction between the cooler/warmer air and the influence of the Azores in what is still portending to be a N/S split.

After a pleasant day today, for most, and the start of tomorrow, the next low arrives from the NW with the associated fronts arrives on Wednesday and the latter cross the country clearing into the North Sea by Thursday

The low continues to track east en rout to Scandinavia leaving the UK in a showery north westerly before some brief ridging on the Saturday and far less frequent showers. By Sunday 00z a deep low has tracked NE to be SW of Iceland and the associated fronts are starting to impact the NW and depressing the ridge somewhat. The low in fact is the result of TC (Gert) phasing with a another depression over NE Canada on it's travels.and then hitching a ride on the jet.

The fronts only really effect the northern half of the UK before petering out against the ridge  And this appears to be the message from here as the resurgent Azores behind the main depression once more, according to the gfs, becomes very influential next week portending a dry spell for most, the exceptions being possibly N.I and Scotland, albeit the temps no great shakes.

 

 

[mushymanrob]

8 hours ago, Allseasons-si said:

I am really liking the 6-10 and the 8-14 day from noaa if it is correct,nice southerly plumes on them i would of thought

now come on op's play catch up

trouble is, we keep the mean upper westerly and the high pressure remains to our south. good news for southern areas, and indeed there might be a plume if we get ridging crossing the uk. thats always likely with high pressure close to our south, but we still get a westerly flow.

[Summer Sun]

High pressure gradually building in during next week according to ECM

[knocker]

The ecm this morning is actually in quite good agreement with the gfs all things considered, At 12z Sunday it has the main low SWS of Iceland with the fronts impacting the NW of the UK. The north remains in the circulation of the low over the next 48 hours as the it tracks NE and loses it's identity before the Azores ridges in for the rest of the run.Essentially it typifies the N/S split in these pattern although the runs this morning could well be indicating a more general settled spell, albeit not necessarily of lengthy duration. But as ever this is over a week away but would not be out of place within the projected upper air analysis.

 

Edited August 15, 2017 by knocker

[stodge]

Morning all

Yes, Hurricane Gert doing us a huge favour by lifting the jet north next week and allowing pressure to rise from the south so an increasingly dry and settled theme to the models this morning.

Not hot, it's fair to day but pleasantly warm  - the problem is the HP meanders around to the west and sometimes drifts far enough away to allow weak frontal systems to move down from the north west bringing in cooler air. On other occasions, the HP drifts NW and with pressure lower to the south with the Iberian LP, there's always the hint of an E'ly flow for the far south and possible attendant thundery showers but little evidence of a plume or any influx of hotter air at this stage through to month end.

[mb018538]

Next Monday could be the warmest day for quite a while, somewhere could top 80f:

All in all, not a terrible outlook, though lots still to iron out.

[phil nw.]

The ens outputs are showing perhaps a more settled outlook towards week 2 with more influence from the Azores high modelled to move across the UK.

The day 10 charts both from this mornings GFS and the overnight ECM mean show this

The Greenland trough shown to have shrunk losing it's influence as the high ridges in quite strongly. 

A look at the pressure ens graphs for both Warks and Aberdeen confirm the pretty widespread pressure rise in week 2 

 

It doesn't look like a heatwave though as we are still under relatively cooler air as the high builds in but never the less it should be quite pleasant if this pattern should verify.

Fingers crossed that Summer may go out on a more cheerful note.

 

[Summer Sun]

4 hours ago, mb018538 said:

Next Monday could be the warmest day for quite a while, somewhere could top 80f:

All in all, not a terrible outlook, though lots still to iron out.

As things stand Hurricane Gert could be what is required to get some warmth back with it tracking NW of Scotland it should drag up some welcome warmth 

Edited August 15, 2017 by Summer Sun

[mb018538]

Bit of difference again on the 12z, GFS keeping the low further away to the north, whereas UKMO tracks it over the UK and is therefore much more unsettled. 

Why cant they just get along and agree for once! 

[northwestsnow]

42 minutes ago, mb018538 said:

Bit of difference again on the 12z, GFS keeping the low further away to the north, whereas UKMO tracks it over the UK and is therefore much more unsettled. 

Why cant they just get along and agree for once! 

So frustrating!!

UKMO looks poor , whereas GFS looks good.

Hoping ecm sides with gfs.

[chris55]

Haven't posted for ages, snow and cold seems to be my vice lol. However with an important outside event upcoming (26th) and potential hurricane Gert set to potentially and finally shift the jet north, the mid term NWP is on my radar! 

I'm pretty sure we will finally break this awful August at some point (we have to, surely?) and the models are finally hinting at such a change.

A long way to go mind, here's hoping summer gets a reset towards the end.