Model Output Discussion 12hrs. 01/10/13

[Frosty.]

Well. tonight's Ecm 12z operational run is another peach, very good agreement now for the weather to settle down by the weekend and through next week, only the northwest corner of the uk being a bit windier and more unsettled but for most of the uk, it looks increasingly warm and settled with lots of sunshine and winds becoming light and variable, it's another SSsssmokin ecm run....BANK 

[smithyweather]

 

But what is so good about 18c and cloud in mid-October? Isn't about time we have some more autumnal weather???

We've got ample time for cold weather yet

 

we've got the second half of October, November, December, January, February and possibly march

 

Something more unsettled / cooler is bound to arrive at some point but now those seeking cooler weather need to have a bit of patience

 

Any way ECM ends settled but cooler which could allow fog to  develop overnight and maybe some frosts in sheltered parts

 

 

 

Yea but it's October and not August. Maybe you didn't notice but it's warmer in the British isles more than it is colder so I think we've already had ample warmth it's about time we have some cold. So no there actually is not ample time for cold.

 

All i'm asking for is frosts and sunshine, i'm not expecting snow or anything just some cold nights i.e not 12c...

Edited October 1, 2013 by smithyweather

[cold snap]

Nice to see some cold pooling within the last frames to are far north from ECM and GFS,we'll out of the reliable of course.

Could be a change within two weeks

[Summer Sun]

Latest from Gibby

 

Good evening folks. Here is tonight's trip through the midday outputs issued by GFS, UKMO, GEM, NAVGEM and ECM for today Tuesday October 1st 2013.All models show a similar sequence of events to this morning with the rest of the week seeing a change to wetter and more volatile conditions, albeit just for a short while. Through this period while still mild there will be some heavy rain already in the SW spreading slowly NE tonight with another potent area of very heavy rain expected on Thursday with a short bright and showery period in the day tomorrow. Behind Thursday's rain fresher air will move East across the UK by Friday with a pressure rise likely as High pressure develops over Southern Britain at the weekend. So after some showers on Friday the weekend looks dry and bright over the South and East and still relatively warm while the North and West remain at risk of more cloud, wind and at least a little rain at times.

 

GFS then shows High pressure receding away East into Europe next week with a warm SE flow again prevalent for several days under falling pressure with an increased risk of rain from midweek. Things remain changeable then out to the end of the run with SE winds and a broad trough near the UK continuing to deliver occasional rain leading into a more Autumnal and Atlantic westerly type flow to end the run.

 

UKMO tonight closes it's run with High pressure receding away over Europe too with a weak SE flow carrying rather cloudy and misty weather from Europe over the UK. The far NW could see thicker cloud with some rain at times with temperatures near or a little above normal.

 

GEM tonight shows High pressure weakening slightly early next week as it slips East into Europe. However, it never really loses it's grip entirely maintaining a lot of dry and quiet weather over the SE while the West and North see a spell of windier weather as Low pressure swing SE to the NW of Britain with some rain at times for all these areas through the week.

 

NAVGEM too shows High pressure gradually moving away East over Europe next week with some rain in the North and west at times as the week goes on. Temperatures would remain close to or somewhat above normal.

 

ECM again comes up with a more prolonged fine and settled spell next week with some fine and potentially warm weather to be had with some foggy nights possible in light winds. Should this form it may prove stubborn to clear in the mornings making it rather colder here. As the responsible High pressure weakens into slack pressure at the end of next week a small Low raises the risk of some scattered rain or showers late in the run in the North before renewed cooler and dry weather develops as new High pressure moves in from the West.

 

The GFS Ensembles show uppers consistently higher than average for the duration of tonight's run especially in the South. After this week's short burst of rainier weather another period of largely dry conditions looks likely especially in the South where even the recent indications of the return to more unsettled conditions by the end of the run not very marked tonight.

 

The Jet Stream shows the flow currently blowing East over France moving North later this week towards the NW of Scotland where it undulates slightly North and South next week. The very end of the run shows a very strong surge across the Atlantic towards the British Isles which is what is needed to potentially spawn some more powerful Atlantic depressions than we have seen so far this Autumn. It is shown as being nearly two weeks out though.

 

In Summary the weather still looks like becoming dry and fine again for many next week as High pressure developing over the UK at the weekend only slowly slips away SE raising the risk at least of a little rain in the South again later next week. ECM still has other ideas keeping High pressure in control with a warm feed through the week and a cooler feed the following weekend as a new High develops to the West. Whatever happens it still looks as though we are along way from our first notable frost of the season and from any serious blow or reservoir filling rainfall once this week's brief downpours pass.

 

http://www.norton-radstockweather.co.uk/Model-Analysis%282859336%29.htm

[Frosty.]

Fantastic model output from saturday onwards for those of us who enjoy fine and warm weather, exceptional weather by october standards and still no sign of a full blown pattern change even remotely on the distant horizon...it's all a bonus now so make the most of it. : - )

[phil nw.]

But what is so good about 18c and cloud in mid-October? Isn't about time we have some more autumnal weather???

 

 

Yea but it's October and not August. Maybe you didn't notice but it's warmer in the British isles more than it is colder so I think we've already had ample warmth it's about time we have some cold. So no there actually is not ample time for cold.

 

All i'm asking for is frosts and sunshine, i'm not expecting snow or anything just some cold nights i.e not 12c...

 

 

Let's be honest here, there is no way a settled spell will last for 2 weeks in October. I think your getting ahead of yourselves.

 

Just a reminder folks that there is the other Model thread here-

http://forum.netweather.tv/topic/76235-model-banter-moans-and-ramps/

 

for more subjective comments or talk about weather preferences.

[joggs]

Well im happy that the models continue to build high pressure our way(if it comes off!),we have plenty of time for autumnal weather so we might as well rest the central heating lol.Kerching.

Edited October 1, 2013 by joggs

[Captain Shortwave]

ECM mean day 10 sums up where we are

 

GFS mean for the same time

Very stable Euro-high pattern. Given the lack of energy in the Atlantic this set up will be very hard to crack to be honest.

I think this could last beyond mid-October the way things are going.

If the flow comes in off the continent it will be very pleasant with sunny skies and cool misty nights. Nothing wrong with that.

[Scorcher]

Yea but it's October and not August. Maybe you didn't notice but it's warmer in the British isles more than it is colder so I think we've already had ample warmth it's about time we have some cold. So no there actually is not ample time for cold.

 

All i'm asking for is frosts and sunshine, i'm not expecting snow or anything just some cold nights i.e not 12c...

 

I think you may need to rein in your expectations as it's only early October and frosts are not the norm for most of us this early in the month. In fact many parts of southern England (and often areas further north) generally don't see an air frost until November. In case you've forgotten we were still enduring cold in May so I think many will welcome the warmth hanging on into October.

Edited October 1, 2013 by Scorcher

[smithyweather]

Off topic but first frost date here is Mid-October so it is not long to we experience our first frost here normally. - From current date.

Edited October 1, 2013 by smithyweather

[Weather Boy]

Its only epic if you want a contiuation of cloud and very mild temps. You see I wouldn't mind the high pressure if it brought sunshine and frosts, but thats not going to happen.

I think that newer members would be pleased if you could say why you hold the view that there will be a lot of cloud, as would I. Personally I have yet to work out how to distinguish a cloudy high from a clear high and welcome any guidance on that from those who know more. So what makes this a cloudy high?

[smithyweather]

I have no idea how you would do that. I am still finding difficulty after all this time, tbh most of the members just post charts and say 'oh this would be brilliant for cold or warmth' but they don't explain why. 

 

I don't know what a cloudy or clear high would look like i'm just basing it on experience on where I live and usually here the azores high will bring cloud and low diurnal ranges. 

As for what makes it a cloudy high? Not got a clue but i'm going to take a wild guess and say that the moisture from the atlantic (azores high) produces high humidity which is condensed into clouds and since the sun is not strong enough the cloud just stays for days on end. 

Edited October 1, 2013 by smithyweather

[Frosty.]

I don't think it will be a cloudy high, patchy cloud cover yes but not overcast apart from early mornings before it breaks up,, although winds will initially be a moister sw'ly drawn up from the azores, the wind direction then looks like backing more to due south to se'ly and we will then import drier continental air and clearer skies with longer sunny spells and warmth.

[Thundery wintry showers]

Looking at the current model outputs, the odds favour sunnier than average conditions from the high over England and Wales, as we pull in continental air via a relatively short sea track over the English Channel, rather than having easterlies bringing moisture in off the North Sea.  However, there is a greater chance of there being some cloudy days mixed in at this time of year than earlier in the season, because the weaker solar strength means that banks of low cloud are more likely to hang around for a while on the continent, which can sometimes be imported into the British Isles, while low cloud and fog that forms overnight over the British Isles can be slow to shift during the daytime.  Thus, at this range, it could be anything from slightly sunnier than average to exceptionally sunny.

 

For Scotland and Northern Ireland cloudy conditions are likely due to the moist west to south-westerly flow if the ECMWF is right, but the GFS shifts the high a bit further north which would promote sunnier than average conditions.

 

As things currently stand I think we're only likely to see a generally cloudy high south of the Scottish Lowlands if the models revise its position significantly, but cloud amounts can catch us all out sometimes during the winter half-year.  I remember one instance around mid-March 2012 when I predicted that a high would bring plenty of sunshine thanks to a southerly regime, but a bank of cloud formed over the British Isles overnight and brought a couple of mainly cloudy days afterwards- whereas in contrast, just ten days later, a high in a similar position brought clear skies almost nationwide.

[Mark Parsons]

But what is so good about 18c and cloud in mid-October? Isn't about time we have some more autumnal weather???

Whats good about it is if you work outside the damned winter is shorter!!!!

[smithyweather]

I don't think it will be a cloudy high, patchy cloud cover yes but not overcast apart from early mornings before it breaks up,, although winds will initially be a moister sw'ly drawn up from the azores, the wind direction then looks like backing more to due south to se'ly and we will then import drier continental air and clearer skies with longer sunny spells and warmth.

Now is this for England or is it British isles wide?

[draztik]

Regarding cloud cover, the ECM 12z will supply many breaks in cloud, giving long sunny spells in England & Wales. However, it looks like being fairly cloudy in N.I. and Scotland, from start to the end of its run. If ECM verifies, people in the South may need to pinch themselves, as they sit out in the sun with temps in the low 20s?

Is it really October, or mid August!!

Edited October 1, 2013 by draztik

[Frosty.]

Now is this for England or is it British isles wide?

Most of the uk if the models are right, however, the models show low pressure influence to the northwest of the uk so the nw corner of the BI which covers n.ireland, n and w scotland could be breezier and cloudier with fronts brushing across bringing occasional rain, it all depends on the eventual extent of the azores / euro anticyclone. Edited October 1, 2013 by Frosty.

[Chris K]

GFS 18z run really is showing a rinse and repeat pattern of what we have had since Humberto headed across the Atlantic last month. (Of course i'm not saying it will definitely happen as it shows tonight, as there will never be an "exact" repeat)

 

So...it's currently showing...

• Trough heads towards the UK, bolstering the high which transfers into Europe bringing mild air originally from the SW, swinging round to a flow from the continent
• Low pressure system heads NE grazing NW parts.
• Secondary Low forms and dives to the SW of the UK. Becomes sluggish and begins to fill in
• Another system starts sliding down towards the Low that is filling in to our SW.
• Question is...will it then do another push of rain up from our South, similar to what we are having over the next couple of days?

Also, an interesting post from 10 days ago, because in my view, snowking, as well as others, have been very close, if not spot on many times this year. And so far this little summary from him below seems to be on track so far?? (I'm not brown-nosing honest! From a learning perspective, I just enjoy scanning through posts from over a week before to see how people's views have panned out) 

 

----------------------------------------------------------------------------------------------------------

 

 Posted by snowking on 21 September 2013 - 13:57 in Forecasting Model Discussion

MJO Phase 6 signature (increasingly unsettled) beginning to be reflected in the days 5-10 NWP output. Expect some further swings for a couple of days yet as I imagine NWP is probably still having a little difficulty in resolving the energy fusing in to the jet stream from Humberto. Hopefully in to Monday/Tuesday a more consistent signal should begin to appear...and unfortunately that consistent signal looks as though it will be an unsettled one.

 

The next shot at something more settled currently around days 15-25, with little coherent MJO or GWO signal as both tropical convection and global angular momentum fall to average levels...this is not a guarantee of settled conditions, merely the best chance of such conditions.

 

Beyond that there is a growing trend from OLR plots to introduce something around phases 1/2/3 through the second half of October - all three of which suggest something rather unsettled.

 

So as a rough timetable based upon current projections:

 

27th Sept - 5th October - Unsettled

6th-16th October - Something more settled?

17th October Onwards - Unsettled once again

 

Timings are of course approximate

 

SK

 

-----------------------------------------------------------------------------------------

 

 

I hope he doesn't mind me referencing his comments in this post

Edited October 1, 2013 by Chris K

[Frosty.]

Sensational, stunning Ecm 00z op run, high pressure heaven and becoming very warm for the time of year, not much else to say really, it's an amazing run for this stage of the autumn, you don't expect summery charts like these towards mid october in the uk but then, we have had some amazing weather this year so why not have more..

[Frosty.]

And the UKMO 00z is also a cracker, that anticyclone would look even stronger by T+168 hours summery weather here we come..again settling down from the weekend as the azores high builds in strongly, warming up, becoming sunnier and eventually even the far northwest joining in the fun, superb october weather on the way.

[Frosty.]

One word springs to mind with these charts...BLOCKED... 

 

The Gem & Gfs 00z are also looking very anticyclonic as we go deeper into october, amazing output this morning.

[johnholmes]

Well at last the anomaly charts seem to have got over the autumn blues, this year taking a lot longer than I have known over the past 3-4 years.

The pattern they seem to be settling down to is shown below, first the ECMWF-GFS from this morning

http://www.meteo.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

 

then the NOAA isuue last evening for 6-10 and 8-14

http://www.cpc.ncep.noaa.gov/products/predictions/610day/500mb.php

 

The ECMW-GFS and 6-10 NOAA are very similar. What will be interesting is if the suggested upper pattern on the 8-14 does develop. Essentially it is a very similar one to the 6-10, just less marked; the main trough remains west of the UK suggesting that there is no cold outbreak before mid October at the very least.

[simshady]

And the UKMO 00z is also a cracker, that anticyclone would look even stronger by T+168 hours summery weather here we come..again settling down from the weekend as the azores high builds in strongly, warming up, becoming sunnier and eventually even the far northwest joining in the fun, superb october weather on the way.

 

To be honest it's hardly summery really, just normal September/October weather. Grey days followed by some warmer days interspersed by spits and spots of rain.....last year was virtually the same in my neck of the woods if a little wetter. Describing it as summery can be a little confusing to new people who are getting to grips with the charts. Might be warmer and more summery the further south you go but here 'oop north it's not necessarily so.

Edited October 2, 2013 by simshady

[Frosty.]

To be honest it's hardly summery really normal September/October weather. Grey days followed by some warmer days interspersed by spits and spots of rain.....last year was virtually the same in my neck of the woods if a little wetter. Describing it as summery can be a little confusing to new people who are getting to grips with the charts. Might be warmer and more summery the further south you go but here 'oop north it's not necessarily so.

I would say low to potentially mid 70's F for the south & east and potentially low 20's c for the north and west would be summery by early to mid october standards, the near continent, the azores and southern europe is still very warm and that is where our air will be coming from these are the best charts you could wish for at this stage of the autumn..huge potential with an anticyclone becoming centred to the east enabling a warm flow.