Model Output Discussion 31/03/14 onwards.

[knocker]

Regarding next weekend the upper anomaly is changing slowly according to the ECM. The situation still much the same over the UK with the warm air to the east making little headway but the western block is slowly weakening, a card that the ECM has been playing for some time that wil eventually lead to a westerly flow. In the meantime the surface is dominated by a low to the west of the UK giving SWs over the UK giving fairly settle weather but showery with temps around normal.

 

 

[Frosty.]

The Ecm 00z op run shows the very warm uppers (T850 hPa) persisting across the east of the uk for much of the week ahead although pressure will be falling with an increasing risk of thundery showers with torrential downpours between very warm sunny periods, further to the west and southwest, closest to the main trough, the weather slowly trends cooler and fresher with atlantic air making inroads bringing more extensive cloud cover and  showery outbreaks, again these could be heavy and thundery. The end of the run hints at the azores anticyclone trying to build in with the main trough energy being shunted further northwest meaning the south & east becomes drier and pleasantly warm with the most unsettled weather eventually becoming concentrated across the northwest of the uk....all in all, can't really complain about this weather, it's warm or very warm..hopefully a sign of things to come this summer.. cheers all 

[tinybill]

looking at the models deep in to fantasy world  i hope its  not the start of our monsoon season its not looking very nice at the  moment after Wednesday

 

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=2&ech=6

 

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=2&ech=204

[mushymanrob]

hmmmm ..... theres a huge difference this morning between the operationals and the anomaly charts. i always use the anomaly charts now for the best indication of what might lie ahead beyond 6 days time, they are very accurate when they agree, and even when they dont they are still pretty close.my feeling is that this weeks complex area of low pressure close to us throws up too many solutions and throws the evolution out of sync.... i like the anomaly charts which suggest the mean upper trough will drift further away from us and with high pressure to our northeast and far northwest lock in the trough. so whilst itll be unsettled at first, it should dry up especially in the northwest as the uk picks up a southeasterly draft. if the anomaly charts are correct, the last week in may should be a very pleasant one, especially in northwestern areas which could become hot.however, the anomaly charts, whilst most accurate 6 days ahead +, can change dramatically overnight, being such a long range prediction. so which set of runs will be right? the operationals that suggest a messy unsettled, warm but showery/thundery/muggy regime until the end of the month, or the anomaly charts which suggest it becoming drier and warmer especially away from the southwest. (after an unsettled week).

 

 

oops..... think once, think twice, think 'read the dates before making an incorrect comparison'... lol. yep i was viewing yesterdays anomaly charts and comparing them with todays ops.ill get my coat.

[Polar Maritime]

Morning Mushy good to see you posting again, Yes I think you need a strong Coffee.. 

[Frosty.]

ill get my coat.

no need for the coat mush..t-shirt and shorts weather today

[Summer Sun]

GFS 00z ensembles showing some fairly steady pressure from the 26th to the end of the ensembles runs

 

 

Although it wouldn't be totally dry conditions should become less unsettled with longer dry spells and of course when your in the sun now its pretty strong so it easily makes up for any lower than normal temperatures

Edited May 18, 2014 by Summer Sun

[vladthemert]

GFS 00z ensembles showing some fairly steady pressure from the 26th to the end of the ensembles runs

 

 

Although it wouldn't be totally dry conditions should become less unsettled with longer dry spells and of course when your in the sun now its pretty strong so it easily makes up for any lower than normal temperatures

 

heavy rainfalls there.   Can I ask do these tend to include convection rainfall or its unpredictable to work so on the day those levels could increase dramatically due to convection.

[knocker]

The ECM EPS similar to ops but the colder air at 500mb is more to the SE. And evolving to the weekend after.....................

 

 

[mushymanrob]

Morning Mushy good to see you posting again, Yes I think you need a strong Coffee.. 

 

 

no need for the coat mush..t-shirt and shorts weather today

 

hi guys.

 

i have no plans to post regularly though, no need for my witterings when others do a far better job.

[Man With Beard]

GFS 12Z maintains unsettled conditions from Wednesday until well into next week, with the depression stuck on top of us. I imagine it wouldn't be non-stop rain but rather spells of rain. With warmer air being pushed out faster, the risk of torrential rain perhaps becoming less. The idea of this low stalling out west is fading fast now.

[knocker]

For the of the week the GFS has the main wet day Thursday. Rain spreading up from France starting at midnight  By midday the heavier rain is over norhern England with the low 998mb centred there.

[Summer Sun]

For the of the week the GFS has the main wet day Thursday. Rain spreading up from France starting at midnight  By midday the heavier rain is over norhern England with the low 998mb centred there.

 

Yep looking like Thursday could potentially be the wettest day of the week once the main band of rain moves northwards showers follow on behind it though parts of the SE & east Anglia could miss those showers

 

Edited May 18, 2014 by Summer Sun

[ANYWEATHER]

For the of the week the GFS has the main wet day Thursday. Rain spreading up from France starting at midnight  By midday the heavier rain is over norhern England with the low 998mb centred there.

As always with these situations though, precip is notoriously  difficult to predict!

[Milhouse]

It all gets a bit messy towards the end of the ECM but pressure is rising so there should be some increasingly dry and pleasant weather to be had but still the risk of showers around. At t+240 the summer version of the beast from the east is lurking just across the north sea.

 

Edited May 18, 2014 by Milhouse

[Captain Shortwave]

Hmm

 

Seems like there are signs of high pressure trying to rebuild to the north/north east of the UK. The GEM showed a similar solution this morning. GFS ensembles show heights rising in that locale too but later on during week 2. So possibly a slack unsettled spell following by the pattern settling down perhaps. No guarantees though.

[Summer Sun]

After an unsettled week ECM shows pressure rising from BH Monday although temps would be down on this weekend the strong sun now would make it feel quite pleasant in any sunshine

 

Edited May 18, 2014 by Summer Sun

[IDO]

It seems that two days ago (only 4 runs) when ECM were running with that heat plume, however the op was completely in the wrong ball park, and in fact the colder option may be closer to the surface conditions come D7.

 

Todays ECM uppers for the 25th 2pm:  2 days ago: 

 

So temps returning to average to just below by Wednesday morning. GEFS London: 

 

The mean 2m temps keep it close to average for the foreseeable. Relatively unsettled throughout but not a washout by any means, especially the further south you are.

 

GFS in week 2 continues with recent output for  a flatter upstream:  

 

Leading to a more Atlantic driven pattern, however the PV has lost its ooomph and it is a rather slack flow, probably allowing for transient short wave ridges and troughs. So drier interludes becoming more likely.

 

GFS FI not really running with a pressure build in our locale yet, the pattern is too flat as a whole, though tentative signs of a Scandi/Euro ridge by the end of the run from the mean.

 

ECM at D10 has the upper trough dig SE into the Med allowing heights to build towards Scandi promoting a surface high to our NE:

 

 

ECM D7-10 charts are not the top of my events that are likely to happen list at the moment; progressive ECM height rises, they ran with that two days ago and we see what that came to. So I will wait to see support from the GEFS for that, though it appears more feasible than their last effort, and GEFS have a cluster heading that way but with a 2-3 days delay. Its a balance between GFS with its Atlantic bias and ECM with its propensity to over do height rises? More runs needed.

 

 

[ANYWEATHER]

It seems that two days ago (only 4 runs) when ECM were running with that heat plume, however the op was completely in the wrong ball park, and in fact the colder option may be closer to the surface conditions come D7.

 

Todays ECM uppers for the 25th 2pm: http:////f1.nwstatic.co.uk/forum/public/style_images/tctc91_simplify/attachicon.gifECM0-168.gif 2 days ago: http:////f1.nwstatic.co.uk/forum/public/style_images/tctc91_simplify/attachicon.gifECM0-216 (3).gif

 

So temps returning to average to just below by Wednesday morning. GEFS London: http:////f1.nwstatic.co.uk/forum/public/style_images/tctc91_simplify/attachicon.gifgraphe6_1000_306_141___Londres (6).gif

 

The mean 2m temps keep it close to average for the foreseeable. Relatively unsettled throughout but not a washout by any means, especially the further south you are.

 

GFS in week 2 continues with recent output for  a flatter upstream:  http:////f1.nwstatic.co.uk/forum/public/style_images/tctc91_simplify/attachicon.gifgfsnh-0-252.png

 

Leading to a more Atlantic driven pattern, however the PV has lost its ooomph and it is a rather slack flow, probably allowing for transient short wave ridges and troughs. So drier interludes becoming more likely.

 

GFS FI not really running with a pressure build in our locale yet, the pattern is too flat as a whole, though tentative signs of a Scandi/Euro ridge by the end of the run from the mean.

 

ECM at D10 has the upper trough dig SE into the Med allowing heights to build towards Scandi promoting a surface high to our NE:

 

http:////f1.nwstatic.co.uk/forum/public/style_images/tctc91_simplify/attachicon.gifECM1-240 (9).gif

 

ECM D7-10 charts are not the top of my events that are likely to happen list at the moment; progressive ECM height rises, they ran with that two days ago and we see what that came to. So I will wait to see support from the GEFS for that, though it appears more feasible than their last effort, and GEFS have a cluster heading that way but with a 2-3 days delay. Its a balance between GFS with its Atlantic bias and ECM with its propensity to over do height rises? More runs needed.

Remember what I said earlier the shift Eastward is normal, models always over do this scenario   :closedeyes:

[damianslaw]

Difficult to call with confidence how things will pan out by next weekend - the position and depth of the trough currently strung out just off the irish seaboard will determine events. The models are suggesting a very slow eastward moving trough, with all parts in the cooler atlantic air by Thursday and plenty of showers and downpours across the country through this slow transition.

 

Heights are projected to remain very strong to our NW and W and also to our east the reason for the slow moving stuttering trough.

 

We struck fortunate this weekend with the dry warm weather, but I suspect our luck will run out for next weekend and a much cooler showery theme is likely to surface.

 

Its a complicated set up at the moment - models are struggling.

[Summer Sun]

Interesting ECM ensemble this evening with it going for a steady rise in pressure from the 26th

 

Edited May 18, 2014 by Summer Sun

[Captain Shortwave]

 

 

The models keep pressure high to the east of the UK with pressure slowly rising from the south as the amplified pattern in the Atlantic relaxes. Probably a north/south split with average conditions would be my bet beyond this coming week. Though with the high over Europe and Scandinavia, then there is every chances of developing drier and warmer weather at times.

Edited May 18, 2014 by ajpoolshark
just to prune response to hidden post

[Gordon Webb]

are these showers over the next few days a case of everyone seeing them or more hit and miss affairs that vary day by day ?

[Frosty.]

The word unsettled will be used more and more in the days ahead, especially from midweek as the weather goes downhill with temperatures tapering off to normal by the end of the week from the west but still pleasantly warm in the strong sunshine.

[knocker]

I've had a quick look at the GFS and fax charts this morning and feel there is little point in attempting any detail for the end of the week and the weekend. Suffice it to say the area of low pressure over the UK persists with a series of troughs circulating and the where and type of rain is going to be dependent on their position.

 

However taking an overview one can't help wondering how much the strange behaviour of the jet stream, already the cause of some very weird weather in the US, and the extreme heat to the east which appears likely to effect the Arctic is aiding and abetting the models struggle to get to grips with our own fairly unusual synoptic set up.

 

With the emergence of late spring, high temperature anomalies typically cool in the Arctic as polar amplification seasonally fades. However, the two Jet Stream weaknesses have continued to provide heat transport and push Arctic temperatures above normal and into ice-threatening ranges. Now, a third hot ridge, this one over Western Russia and Eastern Europe, has emerged and strengthened to provide yet one more Arctic heat delivery engine

 

 

 

Edited May 19, 2014 by knocker