Model output discussion - after the beast, what next?

[John Cox]

16 minutes ago, Midlands Ice Age said:

John..

 Thanks for the note.

I am afraid that I did not carry out examinations as to the reasons, I just noted the common occurrences as I was scanning through the historic re-analysis. If I had got side-tracked I would never have finished!

Typically, I examined up to  168 hours, after the initial date.

I did notice the straight Northerlies of the 19th Century, the fact  that the  Scandy high was south in the 1930's, and afterwards I realised how little cold we had in the earlier years for the period March onwards.

 The interesting thing would have been if we had the data going back to the 17th and 18th Centuries. 

Ah well..

Anyone fancy looking at the 'hot' outbreaks to see a similar pattern?

 I get the impression they are not so numerous, but who knows... 

MIA

I understand. Anyone of us could use your data and do some analysis and present. Thanks again.

It has been a memorable late winter and this is the time for post mortems

[Frosty.]

3 hours ago, Frosty. said:

The Gem 00z ends with warm high pressure centred to the east..I really think after the week ahead we will see above average temperatures widely as the MO are again indicating which is very good news.???

Good news from the Gem 12z too, ends with 21c 70f across parts of the uk!...fingers crossed we will break through the 70f barrier in the next few weeks.??

[Frosty.]

Looking at the GEFS 12z mean, there's certainly some good news in terms of temperatures, at least for southern parts of the uk both in the week ahead and further ahead through week 2..it's not promising a settled outlook but I do get the impression there would be some fine weather, especially week 2...so, considering parts of the SE had 19c yesterday, the idea of reaching or exceeding 21c 70f at some stage during the next couple of weeks sounds quite realistic if we do get a more southerly / southeasterly airflow as the mean suggests!??

[Mike Poole]

The ECM couldn't be more different to the GFS, this looks like the real deal.  PLUME! T216

Edit: And T240 BOOM!

Edited April 8, 2018 by Mike Poole

[Summer Sun]

What a stunning end to ECM 12z

Happy days

[Frosty.]

summer sun beat me to it but what a beautiful end to the Ecm 12z..BANK!???..BBQ time if that verifies

Quote

???????

 

 

Edited April 8, 2018 by Frosty.

[Summer Sun]

It doesn't get much better than this for the 2nd half of April

Bring it on I say

[Mike Poole]

52 minutes ago, Summer Sun said:

It doesn't get much better than this for the 2nd half of April

Bring it on I say

Those TWO charts you quote are quite ridiculously red for the upper temperatures given.  What colour do they use for uppers of 20C?  Meteociel only uses that shade of red for 20C plus.

Be that as it may, the ECM ensemble mean at T240 is saying a big YES to a warm up:

Thats quite a strong signal for a mean chart at 10 days.

Edited April 8, 2018 by Mike Poole

[Dancerwithwings]

57 minutes ago, Summer Sun said:

It doesn't get much better than this for the 2nd half of April

Bring it on I say

Huge same time line differences between the above ECM and the below GFS.......I'm with the ECM

Edited April 8, 2018 by Dancerwithwings

[Summer Sun]

The 12z GFS op is all over the place after Sunday week looking at the London ens - the mean remains above average until at least the 23rd

[Daniel*]

Poles apart were the ECM and GFS judging from gefs very little support however unsettled weather cannot be ruled out (approaching new week looks fairly unsettled improving late on in the week) into following week most likely to affect west. We could see our weather finally settling down as ECM shows an intense anticyclone developing. I reckon there will be some very good useable weather further into April, best is yet to come.

[Summer Sun]

Saturday onwards sees temperatures starting to increase especially so in the eastern side to start with and more widely later on upper teens to low 20's depending on sunshine amounts

[Summer Sun]

ECM and GEM again show some very warm air moving towards the UK as we move out of the weekend thanks in part to that deep low out in the Atlantic

The GFS 7-day forecast mean shows temperatures widely above average and locally significantly so

[Summer Sun]

The 00z GFS op beyond day 7 is not in sync with the mean and control again this morning on the London ens

The mean and control keep the 850's quite a bit above average for the next 2 weeks at least

[Frosty.]

Lovely stuff from the Ecm 00z..summery charts in april!?

[Frosty.]

I mentioned how great the Ecm 00z was earlier but the Gem 00z is also very impressive with 21 to 22c 70-72f indicated!..hope we are trending towards an early summery spell ???

Edited April 9, 2018 by Frosty.

[stodge]

Late morning all

A damp and disappointing start to the week in London but some signs yesterday of a hint of something better around or just after mid-month. This morning takes us to Thursday April 19th and we kick off as always with ECM 00Z at T+240:

A strongly anticyclonic with plenty of dry and warm weather from an HP centred over Denmark. The easterly this week fades by Friday but the Atlantic disrupts north and south as the LP approaches western Europe with heights rising to the east and LP deflected north and south.

GEM 00Z OP at T+240:

Similar to the ECM and the evolution not too different.

GFS 00Z OP at T+240:

A very different evolution with persistent heights east from Greenland preventing the Atlantic KLP disrupting north so the whole LP moves SE keeping the weather unsettled especially over southern and western parts. Further into FI and the LP persists close to the British Isles even as the Azores HP tries to ridge in from the SW.

GFS 06Z OP at T+234:

A more definite ridge south from heights well to the north of the British Isles means a light ESE'ly for most and decent weather with the LP kept well to the SW. Further into FI and a brief flirtation with warmth is replaced by cooler conditions as heights end up to the NE with LP to the SW and SE meaning a broadly northerly flow over the British Isles but the coldest air always well to the east.

GFS 00Z Control at T+240:

More akin to the GEM and ECM than the OP and a more defined SE'ly flow. Further into FI as the LP approaches from the south, the flow shifts more east and eventually north east as the HP retrogresses to Greenland.

The GEFS at T+240:

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

A very strong signal for heights to the east or north east of the British Isles with OP and Control not far apart and leading the majority cluster. One or two Members have the LP a little closer but the net effect t is more wind from the SE rather than anything else.

Further on and plenty of uncertainty as you'd expect but with no strong signal for any particular pattern.

In summary, plenty of agreement this morning on heights building to the east or north east next week. Whether these develop from a disrupting LP to the west or from Greenland is less clear but the net effect is the same. HP to the east brings SE'ly winds so warmer and drier conditions for all. Southern and South-western areas would still be at risk from rain or showers if the 00Z OP verified. GEM and ECM break up the LP and send energy both north and south while GFS moves everything to the south or south east. Quite possible we'd see 20c from the GFS Control, the GEM or the ECM but the east coast would still be at risk from fog.

[Summer Sun]

Little change on the 06z forecast mean for the next 7 days widely above average potentially well above average locally in a few spots

[Wildswimmer Pete]

29 minutes ago, Summer Sun said:

Little change on the 06z forecast mean for the next 7 days widely above average potentially well above average locally in a few spots

Is this a sign of impending pattern change and/or the end of the influence of the recent SSW?

[Man With Beard]

By D10, the ensemble means are quite close to the magic 1030mb mean high to our east

  

Chances of a very warm period (comfortably into the 20Cs) between 18th and 20th April have got to be quite good on that, but not in the bag yet.

ECM ensembles D11-D15 continue on the whole to suggest warm and mostly dry weather incoming - 70% of ensembles going this way on the clusters. Has been a theme for a while.

Though confidence for me is not as high as this - there's been a tendency for the ECM to downplay troughing over Europe for a good 6 months now - and certainly a look at the ensemble mean at T300 is fairly inconclusive:

My feeling is that a longer settled spell will come eventually but may take a go or two to get established.

 

[phil nw.]

Could some sun and warmth finally be on offer next week?I hope so after these last few weeks of an incessant run of wet and often chilly days with very little break around these parts.

Looking at the mean charts at day 10 there is some reason to be cheerfull

 

A building ScEuro high deflecting the jet north and hopefully some warmer air wafting up from the Med/S.Europe on a nice south/south easterly.

 

[Summer Sun]

UKMO 12z and GFS 12z handling Sunday's low very differently

[Mike Poole]

Well. It's a 1040 high on GFS at T228!

 

[Cheshire Freeze]

12 minutes ago, Mike Poole said:

Well. It's a 1040 high on GFS at T228!

 

Will be interesting to see if the retrogressive signal carries on apace.

We could go from pleasant to not very pleasant at all in the space of a day or two...

By the end of the run, it goes on to show that even in late April, the cold can still hit- snow risk returns for Scotland.

Edited April 9, 2018 by CreweCold

[Cheshire Freeze]

Following on from the post above...some musings...if we are to see a S'ly tracking jet stream to end April or even start May, we won't be able to glean a lot about prospects further ahead. Analogues are fairly mixed for HLB in May. Some years show we go on to be very wet ala 2007 and others produce heat going forward. However, I have a feeling that this year we will struggle to break out of any wet period (owing to a rather neutral looking ENSO signal). Potentially a very wet period coming up in the extended (May-June) IMO but we'll see. We may get lucky with ridge placement.