Model Output Discussion 12z 23/05/13

[bluearmy]

looking at the ecm ens mean/spread out to day 10 and the energy is headed further south into europe so i'd say a decent trend in general.

[Methuselah]

Tonight the Irish Met Service have said that temperatures next week will reach 25c over central parts of Ireland, contrast that with the UK Met. and you wonder are we on the same planet. It looks like posters here are well and truly ahead of the game, so well done and enjoy!

Don't forget that we have a cold North Sea and English Channel to think about? Just enjoy your good weather... 

[049balt]

The Irish Met mostly use the ECM model for their forecasts.

I would have thought they would look at most of the models, as we do here

Edited May 31, 2013 by 049balt

[049balt]

Don't forget that we have a cold North Sea and English Channel to think about? Just enjoy your good weather... 

You have no idea how much we will enjoy some warm sunshine, it might even add to our GDP!

[Barry12]

 

Another good, increasingly warm run

Edited May 31, 2013 by Barry95

[Barry12]

Parts of Eastern Iceland reaching 20C

 

https://www.google.co.uk/search?um=1&hl=en&q=egilsstadir&bav=on.2,or.r_qf.&biw=1360&bih=639&ie=UTF-8&sa=N&tab=iw&ei=Dh-pUfzZBOXz0gXk7oGYDg#hl=en&sclient=psy-ab&q=egilsstadir+weather+forecast&oq=egilsstadir+for&gs_l=serp.1.0.0i22i30l2.8030.10449.0.11327.4.4.0.0.0.0.90.342.4.4.0...0.0...1c.1.15.psy-ab.z6bfOUvVaiE&pbx=1&bav=on.2,or.r_qf.&bvm=bv.47244034,d.d2k&fp=ad746c489e9ddf9a&biw=1360&bih=639

 

Edited May 31, 2013 by Barry95

[Tony27]

Gavin will need to get his De -Icer spary out going by the GFS 18z

http://cdn.nwstatic.co.uk/gfsimages/gfs.20130531/18/132/ukmintemp.png

Edited May 31, 2013 by Tony27

[Barry12]

Gavin will need to get his De -Icer spary out going by the GFS 18z

http://cdn.nwstatic.co.uk/gfsimages/gfs.20130531/18/132/ukmintemp.png

GFS has been going mad recently...

[Steve C]

Gavin will need to get his De -Icer spary out going by the GFS 18z

http://cdn.nwstatic.co.uk/gfsimages/gfs.20130531/18/132/ukmintemp.png

 

Zero chance of that verifying, considering the Sun will have risen the best part of a couple of hours ealier.

[AWD]

One would think that this chart would be dry and relatively sunny for all of us;

But looking at the equivalent PPN chart, you can already see the hint of showers breaking out down the western side of the country;

This theme then continues for the rest of the UKMO output;

A typical sunshine and showers pattern there. Some places will have more sunshine, some might see a frequent amount of showers. As ever in this scenario, it all depends on location and luck.

A similiar pattern also developing on this mornings GFS Op run;

The Op a well supported run throughout too, with an increase in PPN as next week progresses;

You can also see this in the SLP, where there is a relaxation in pressure through next week;

This has been the broad trend for a few days now. Temperatures always on the pleasent side though, so where you miss any shower activity, you could find yourself with a good deal of warm sunshine over the next couple of weeks. Just be prepared for some showers in the second half of the coming week however. Not a bad start to summer, little sign of any cool or deeply unsettled weather on the horizon.

Should also add, the above pattern looks fairly well supported by this mornings 500mb anomaly charts too, with positive anomalies to the north of the UK and a trough to the South/South West;

Edited June 1, 2013 by AWD

[Frosty.]

A nice weekend followed by a very nice start to next week on the 00z with an anticyclonic first half to next week with warm temperatures and lots of strong sunshine, however, from around midweek onwards it looks like becoming more humid with an increasing threat of thundery showers but still with sunny periods and a more continental feel to the weather by the second half of next week but there could be some torrential downpours later next week, with high pressure having migrated to the north of the uk and low pressure moving up from france across southern england.

[Gibby]

Good morning everyone. Here is my take on the midnight outputs of GFS, UKMO, GEM, NAVGEM and ECM for today Saturday June 1st 2013.

All models continue to show a similar course of events as we progress through the next 7 days. The UK weather through the next week will be governed by the transit of High pressure to the SW of the UK via the UK and away to the North later next week. There will be dry and fine weather for many throughout this period with pleasant and warm sunshine by day but rather chilly nights with some valley mist patches around dawn. Winds will be light and cloud amounts rather variable and sometimes rather large by day. After midweek pressure leaks away over the UK with a slacker airflow pattern developing. With small upper air features floating about and the trend for lower pressure to develop from the South the incidence of showers will increase from midweek with some heavy and thundery ones possible in the South before next weekend.

GFS then takes us through the second weekend and following week with Low pressure close to the SW for a time with thundery showers here while Northern and Eastern parts see dry and fine conditions persist. Through the rest of FI, though a lot of fine and dry weather prevails small disturbances affect the UK at times with the risk of showers never totally eliminated.

The GFS Ensembles show solid agreement with very little spread between members on a period of slightly above average uppers next week before things revert to more average levels thereafter. The North holds on to the driest weather while the South looks increasingly showery for a time perhaps reducing a little later.

The Jet Stream looks like remaining weak and disorganized over this part of the Northern hemisphere for the next week or so. With no definitive pattern there will be fingers of air moving around all over the place in the upper atmosphere over the next week making predicting developments of weather features very hard to predict.

UKMO today has High pressure to the North of the UK to end next week with the UK lying in a slack Easterly flow. Some decent weather will be maintained for many with some warm sunny spells while the South and SW in particular run the risk of thundery showers later.

GEM has high pressure retreating away West then NW later next week and weekend with Low pressure feeding down the North Sea to be centred close to Southern England to end the run with showers breaking out in many Southern areas later while the best of the dry and bright weather retreats towards the NW.

NAVGEM keeps a very slack pressure pattern over the UK at the end of next week and weekend with High pressure clinging on to the UK most influential towards the north and NW. With pressure slowly falling and with lower pressure over the Continent cooler uppers could introduce some showery activity in the South later.

ECM today is disappointing as it pulls up a more coherent area of thundery Low pressure north from France late next week and more especially over the weekend. Thundery showers will break out over the South late in the week with some longer spells of thundery rain at the weekend in developing cool conditions with any dry weather under these synoptics restricted to the far NW.

In Summary there is very little change in the synoptic progression this morning to that of late. The main question is how soon will showers be introduced over the UK in response to the High pressure moving further away from the UK. In answer all models show the risk of this soon after midweek with ECM disappointingly poor longer term this morning with a wet 2nd weekend shown for Southern Britain. Using a broad sweep method the most likely scenario would be for guaranteed dry and bright weather head further NW as here there looks a very good chance of staying dry, bright and at times warm. In the South there will be a lot of this weather too but it would be amiss of me to not mention the risk of heavy showers becoming much more likely with time as we move towards and through next weekend with all models showing Low pressure close to the South to a greater or lesser degree by then.

[Summer Sun]

Gavin will need to get his De -Icer spary out going by the GFS 18z

http://cdn.nwstatic.co.uk/gfsimages/gfs.20130531/18/132/ukmintemp.png

 

Not a cat in hells chance of the happening you only need to look at the highest they could be at the same time

 

 

 

UKMO keeps pressure high till the end of next week but the South SW could see some thundery downpours by this time with a trough developing

 

 

ECM is following its ensemble run from last night for its latter stages in lowering pressure so its no great surprise to see this

 

 

The above has ensemble support from ECM

 

[snowking]

 

 

ECM is following its ensemble run from last night for its latter stages in lowering pressure so its no great surprise to see this

 

 

The above has ensemble support from ECM

 

 

 

 

Yep and unfortunately this looks a very plausible route to me and is exactly in line with the summer expectations, with a changeover date of circa 10th June.

 

We see strong signs of lowering heights and an overall Sceuro trough type development once more from the GFS at day 10 today:

 

 

We can see signs of life from this sort of pattern on this mornings operational ECM too:

 

 

The 12z Glasgow ensembles depict the transition rather well:

 

 

And indeed the tendency shown by the MJO to move into phase 2:

 

 

Corresponds to a similar pattern:

 

 

But perhaps what best illustrates the likelihood of a return to below average temperatures and unsettled conditions is this:

 

 

So from current medium range output the likelihood is of increasingly unsettled conditions by around the 10th of June.

 

Of course before all that, we have some very pleasant days to look forward to - I would expect to see a 24c, perhaps even a 25c before the week is out where the sun stays out all day, and really we couldn't ask for a better start to summer.

 

SK

Edited June 1, 2013 by snowking

[johnholmes]

You can also see this in the SLP, where there is a relaxation in pressure through next week;

image.jpg

This has been the broad trend for a few days now. Temperatures always on the pleasent side though, so where you miss any shower activity, you could find yourself with a good deal of warm sunshine over the next couple of weeks. Just be prepared for some showers in the second half of the coming week however. Not a bad start to summer, little sign of any cool or deeply unsettled weather on the horizon.

Should also add, the above pattern looks fairly well supported by this mornings 500mb anomaly charts too, with positive anomalies to the north of the UK and a trough to the South/South West;

image.jpg

the differences on the 500mb patterns between those shown here by AWD and the NOAA issue last evening in the 6-10 day time range is interesting.

NOAA suggest much less of an actual closed centre upper low. This difference will have implications for the amount and extent of the upper low/trough effect for the south and perhaps how far north this then extends.

On the 8-14 NOAA they have combined a long wave trough shown on their 6-10 from southern Greenland with the relatively minor trough they had close to their -ve height anomalies off Iberia.

So some differences in the 6-10 day and further out but the shorter term looks much as Gibby suggests.

Just seen the post from SK, broadly I would agree with the post but suggest some caution about using the NAO at lengthy time scales, ok for the first week less belief in it on consistency beyond that?

Edited June 1, 2013 by johnholmes

[snowking]

Just seen the post from SK, broadly I would agree with the post but suggest some caution about using the NAO at lengthy time scales, ok for the first week less belief in it on consistency beyond that?

 

Hi John,

 

Completely agree. I was using it more as an easy demonstration of where we were headed as opposed to using it as an actual forecast tool

 

SK

[Frosty.]

Hi John,

 

Completely agree. I was using it more as an easy demonstration of where we were headed as opposed to using it as an actual forecast tool

 

SK

I hope things don't turn out as bad as you say from mid June onwards, I enjoy reading your technical posts though, reminds me a little of Glacier Point who is sorely missed on here by many i'm sure.

[Tamara]

The EPS members at day 7 are showing the scenario consistently suggested in the NAEFS anomaly charts in recent days with High pressure to the north of the UK and lower pressure down to the south and south west which starts to squeeze out the pleasant anticyclonic conditions as we get into and beyond the 8 to 10 day time period.

 

As might be expected the anomaly signal becomes diffused with time but the suggestion is that shallow low pressure takes up residence once again close to the UK with perhaps a weak signal for pressure to rise in the atlantic to the west and again relatively higher pressure towards eastern europe. That suggests fairly unsettled and showery once more and temperatures fairly cool - although without being suppressed in the way they have been through the Spring

 

 

 

It appears its a case of making the most of some fine days ahead before the changes start to occur towards or by the close of next week.

Edited June 1, 2013 by Tamara Road

[snowking]

I hope things don't turn out as bad as you say from mid June onwards, I enjoy reading your technical posts though, reminds me a little of Glacier Point who is sorely missed on here by many i'm sure.

Thank you for your kind words

Believe me I very much hope I am wrong too! I can deal with cold but it's the constant rain during the previous few summers that irritates me.

We should end up better overall than the previous summers, with the next lengthy settled spell likely in mid July.

Looking a little further ahead, the best month of the year could end up being October. But overall we may get off lightly rainfall wise - the near continent looks to have well above average rainfall, and we could see some issues here with flooding as the summer goes on, so anyone with a holiday planned, I wouldn't expect too much weather wise

SK

[049balt]

Yep and unfortunately this looks a very plausible route to me and is exactly in line with the summer expectations, with a changeover date of circa 10th June.

 

We see strong signs of lowering heights and an overall Sceuro trough type development once more from the GFS at day 10 today:

 

 

We can see signs of life from this sort of pattern on this mornings operational ECM too:

 

 

The 12z Glasgow ensembles depict the transition rather well:

 

Screen Shot 2013-06-01 at 09.29.22.png

 

And indeed the tendency shown by the MJO to move into phase 2:

 

 

Corresponds to a similar pattern:

 

 

But perhaps what best illustrates the likelihood of a return to below average temperatures and unsettled conditions is this:

 

 

So from current medium range output the likelihood is of increasingly unsettled conditions by around the 10th of June.

 

Of course before all that, we have some very pleasant days to look forward to - I would expect to see a 24c, perhaps even a 25c before the week is out where the sun stays out all day, and really we couldn't ask for a better start to summer.

 

SK

Now I am depressed, if this scenario materialises are we likely to see a return of last years heavy rain and which parts are likely to be the wettest?

[J10]

http://www.cpc.ncep.noaa.gov/products/predictions/610day/500mb.php shows slight difference to the analyses above, as with the others LP building to the South East, but perhaps not making as much progress northwards as some of the other above. It does seem quite likely some sort of breakdown form the south is now likely, as to whether this is a temporary one with PP rebuilding from our west the Azores High seems quite likely to help us, or a longer period of unsettled weather is another matter.

 

One final word of warning about "upper" charts, they often show trends well in advance to actual surface changes, how long last winter was it going for High Pressure over Greenland, before it actually happened.

[Jezzer]

After a few days of excitement for warmth/sun lovers it's back to reality with a bump after reading this morning's comments.

This brief spell if decent weather looks like it's going to be followed by more dross.

Not sure I could cope with another soggy summer! Any glimpses of hope long term?

[Kentspur]

Thank you for your kind words :)Believe me I very much hope I am wrong too! I can deal with cold but it's the constant rain during the previous few summers that irritates me.We should end up better overall than the previous summers, with the next lengthy settled spell likely in mid July.Looking a little further ahead, the best month of the year could end up being October. But overall we may get off lightly rainfall wise - the near continent looks to have well above average rainfall, and we could see some issues here with flooding as the summer goes on, so anyone with a holiday planned, I wouldn't expect too much weather wiseSK

Interesting you mention mid July as the next settled spell-my birthday 15th is famous for it being dry St swithuns day:-))

[Scorcher]

After a few days of excitement for warmth/sun lovers it's back to reality with a bump after reading this morning's comments.

This brief spell if decent weather looks like it's going to be followed by more dross.

Not sure I could cope with another soggy summer! Any glimpses of hope long term?

 

As far as I'm concerned there is plenty of hope, it looks mainly dry and fine into FI so there's no point worrying further ahead, these long term signals give us indications of what may happen but they are not nailed on, just enjoy the next few days is what I say. If you're a warm weather fan there's no need to depress yourself by looking for a breakdown, it will come when it comes, for now the sun is out (it could be warmer I know, but it's out!).

[Summer Sun]

The latest met office update to mid June aint too bad really

 

UK Outlook for Thursday 6 Jun 2013 to Saturday 15 Jun 2013:

 

There will still be a good deal of fine and dry weather, although cloud during Thursday could be thick enough to produce a few isolated sharp showers. On Friday and into the weekend, there will be an increased risk of rain or showers, some heavy with thunder, initially across southern parts with the risk of becoming rather more widespread with time. The best of the drier and brighter weather will remain in northern and western areas. Temperatures will remain generally around normal, but above normal in sunnier areas inland, especially in the west, and conversely cooler around eastern coasts. The following week may continue to see some unsettled weather around the UK, with showers or longer spells of rain interspersed with drier and brighter conditions.

 

We've had worse starts to a UK summer

Edited June 1, 2013 by Gavin.