Model Output Discussion 06Z, 13 Sep. 2013 ---->

[Frosty.]

The latest met office update is pretty much as the Ecm 00z ensemble mean shows (charts I posted on this page) with an increasingly unsettled spell arriving by the weekend and then continuing through next week, some of the showers and persistent rain are likely to be heavy with a risk of thunder but there will also be drier and sunnier spells at times, most of these tending to be across the south & east of the uk, especially later in the period as the balance shifts with the northwest of the BI eventually having the most unsettled, windiest and relatively cooler weather with only short lived clearer interludes. For the next week or so, winds are likely to be generally from the south, sometimes south of east and south of west which is a very mild direction but in the more prolonged spells of rain from the end of this week it will be feeling cool but in any sunshine it will feel rather nice, as time goes on, a northwest/southeast split is likely with pressure rising to the southeast across the near continent but pressure generally low to the northwest of scotland. In the meantime, a pleasant spell but with large areas of cloud although the late september sun will punch some holes in the cloud sheet at times and where skies clear overnight for any length of time, that's a recipe for thick fog patches to form, eventually the risk of fog will vanish as winds freshen or indeed strengthen at times through next week, there is still an olive branch of hope for indian summer conditions to develop during october with a lot of fine and warm weather possible, especially for the south & east.

Edited September 23, 2013 by Frosty.

[MR EXTREMES]

take your pick looks like autumn will arrive at long last.

and potential to become fairly stormy with high rainfall totals.

 

and average but slightly above for the south at times.

 

jma at t144

gfs t144

ukmo t144

gem at t114

gefs at t144

gefs Jetstream at t144 way to the south

gem Jetstream t144 adding fuel to developing systems to our southwest.

intresting but clear indication the autumn weather is approaching possibly stormy in time.

 

navgem takes low heights south with heights building around scandi area.

although other models don't agree.

[Captain Shortwave]

^Navgem looks similar to the last couple of ECM runs

(Example chart from this morning)

 

ECM has shown this solution the last few runs and the only model showing any real consistency (shown the same solution past day 7 on the last 3 runs). UKMO has moved in weakening the energy heading west towards Scandinavia, it's starting to move towards that solution. GFS looks lost in my opinion. 

I think something close to the ECM will be the correct answer with a cyclonic southerly flow bringing rain and showers at times with temperatures at or a little above average.

I think autumnal storms are unlikely at this juncture, especially considering we are on the quieter side of the pole at the present moment.

Also JMA doesn't update until the same time as the ECM so that's yesterdays run

Edited September 23, 2013 by Captain shortwave

[draztik]

If we are to believe the ensembles, then some stormy weather for t192 approaching, looks nailed on with cross model support. Using 12z gfs ens & 0z ecm/ggem

[Summer Sun]

GFS 12z ensembles suggest above average uppers lasting till October 5th this evening before falling to average

 

 

[Captain Shortwave]

If we are to believe the ensembles, then some stormy weather for t192 approaching, looks nailed on with cross model support. Using 12z gfs ens & 0z ecm/ggem

Unsettled yes, stormy not. A moderate southerly breeze never used to be described as stormy. The operationals show nothing worse either at the moment.

Friday/Saturday could provide something interesting with 12-14C uppers and an active cold front pushing east

4 runs on the bounce from the ECM has shown this high form to our north east

Edited September 23, 2013 by Captain shortwave

[Frosty.]

The Gfs 12z operational & Gefs 12z control run are showing an unsettled spell developing from later this week which is in line with the latest met office thoughts, the unsettled spell lasts for some time but it's interesting to note that later in FI both the control and op runs show an anticyclonic spell evolving through early october which just happens to be what the met office are currently thinking but the Gefs 12z mean currently looks more unsettled in that timeframe, however, sometimes the gfs is very good at picking trends a few weeks in advance..maybe this is another of those occasions.

[Milhouse]

Increasingly unsettled but staying warm looks to be the way things are going as we approach the weekend. With high pressure dominant to our northeast i cant see any way through for low presssure so it looks like staying over or just to the west of the UK dragging up more warm air.

 

[Milhouse]

Rather unsettled and warm from the GEFS ensemble mean in a weeks time with the best of the dry weather to be found in the east.

 

Edited September 23, 2013 by Milhouse

[Cloud 10]

Could be some fireworks over Southern France on Friday with +2016 uppers. 

 

[Captain Shortwave]

Again like previous ECM ops the Atlantic low is really struggling here

Bit of a tease maybe but again warmth from the south is pushing northwards

Edited September 23, 2013 by Captain shortwave

[Summer Sun]

ECM showing a deep low at t192 as per the ensemble this morning it however doesn't get fully in and instead it just sits in the Atlantic losing strength

 

 

Huge area of high pressure developing to our east

 

t240 has the centre of the low passing western Ireland and Scotland

 

 

Remaining mild

 

Edited September 23, 2013 by Summer Sun

[ANYWEATHER]

I Think sooner or later we will have the clash of the air masses. The Artic is pounding with increasing cold whilst the tropical storms in the Atlantic inject some heat over the Uk, quiet for now right up to Friday, then perhaps some Autumn storms into October....  

[Man With Beard]

 

Now this one is a real forecaster's nightmare. Fronts approaching from all directions, one bring colder weather from the north, the other meandering back and forth. The current warmer air squeezed in the middle. Just about any weather could come out of this except snow - sunny spells/v warm, showers, heavy rain, colder air. Maybe all of them. Surely the risk of some real downpours too?

[Summer Sun]

Latest from Gibby

 

Good evening. Here is the report on the midday outputs from GFS, UKMO, GEM, NAVGEM and ECM for today Monday September 23rd 2013.

 

All models show High pressure close to the East of the UK gradually weakening over the coming days giving rise to some warm sunshine by day but thick fog in places overnight. A weak trough intensifies a little towards Northern Scotland tomorrow and on Wednesday a showery trough of Low pressure will move North across Western areas late in the day. Some rain for Scotland will sink South tomorrow while showery rain moves North over Western Britain later on Wednesday. Later in the week pressure continues to fall, especially over the South with an increasing threat from thundery rain or showers looking likely by Friday gradually extending North and East to other areas over the weekend. It will stay reasonably warm though until the weekend away from Northern Scotland where it may be rather cold for a time over the next 48hrs.

 

GFS shows Low pressure extending NE across the UK with rain at times, some of it heavy especially in the South. Through next weekend the weather stays changeable with some rain at times as Low pressure continues to track NE across the UK at times. Temperatures would remain close to average on the whole with a change to somewhat more settled weather shown at the end of the run as High pressure slowly builds in from the West with bright days and fog again at night.

 

UKMO tonight shows Low pressure gaining strength near Southern Britain with some heavy rain or showers here with any fine and dry weather becoming confined towards the North and East where a cool SE wind develops.

 

GEM shows a feed of Low pressure from the SW on several occasions from the end of the week out to the end of the run each one pushing rain bearing fronts North and East across most areas with the most rain across Southern and Western areas with drier and brighter interludes most likely in the East while near average temperatures look likely.

 

NAVGEM shows High pressure out to the NE while deep Low pressure lies to the SW with fronts crossing NE over the UK at times bringing outbreaks of heavy rain at times with just brief brighter intervals. The most rain will concentrate on Southern and Western areas while the best of the brighter spells should be towards the North and East away from North Sea coasts.

 

ECM shows Low pressure anchored close to SW Britain with troughs pushing NE across many areas on regular occasions. With the air from Southerly latitudes the air would be inherently warm though the sheer expanse of cloud cover for much of the time would restrict temperatures to average levels. This same warm source of air could make some of the rain very heavy and thundery at times.

 

The GFS Ensembles indicate the closest grouping between the members for some considerable time with solid support for a steady fall in uppers over the coming few weeks eventually reaching the seasonal average. After a few more dry days the risk of rain for all increases with some quite wet conditions possible at times through the weekend and next week.

 

The Jet Stream shows the flow to the North weakening and becoming obsolete over the coming few days before the flow relocates to the South of the UK where it looks to remain over the reliable time frame tonight.

 

In Summary tonight we have more or less universal support for a change to more unsettled and at times wet weather as Low pressure to the SW comes much closer to UK air space by the weekend. The rain looks like being heavy at times perhaps with thunder as the flow from Southern parts of the North Atlantic will be quite warm. As usual in these situations the heaviest rain will be in the South and West while the NE will possibly see less though with a cool SE breeze on the North Sea coast at times.

 

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

[Frosty.]

There is no denying it's going to become very unsettled from the weekend onwards but tonight's Ecm 12z is at least warm for the time of year with winds sourced from africa/spain, it's probably going to be feeling more humid with showers becoming heavy and thundery, maybe even some imported thunderstorms pushing up from france on friday/saturday and a risk of stalling fronts over the weekend producing a lot of rain as a trough gets stuck over the uk, so for those who think the current weather is boring..that is soon going to change, showers spreading up the western side of the uk through midweek is just a little taste of what's to come, but it does look like staying warm according to this run and in any decent sunny spells it will feel very warm.

[MR EXTREMES]

ecm looks like it could end the ukmo 30 day hopes of an October heatwave lol everything is being pushed well south on the later ecm and scandi heights trying to make its mark intresting.

 

some stormy weather could be on its way plenty of rain now were heading for autumn but overall nice week coming up to end summer of the high side of temps.

[MR EXTREMES]

 

Now this one is a real forecaster's nightmare. Fronts approaching from all directions, one bring colder weather from the north, the other meandering back and forth. The current warmer air squeezed in the middle. Just about any weather could come out of this except snow - sunny spells/v warm, showers, heavy rain, colder air. Maybe all of them. Surely the risk of some real downpours too?

nice polar heights on the fax low pressure taking a dive south very intresting could this be the sign of things to come.

[Captain Shortwave]

ECM ens show pretty good agreement with the operational. Turning more unsettled in the coming weekend, mixed the following week, rain or showers but also some sunny spells and in those sunny spells it would feel quite warm for the time of year.

 

 

 

That low doesn't seem to be making much eastwards progress.

[bluearmy]

upstream, cpc has extremely low confidence. no sh*t sherlock - seemed like that for a long while now !

[Gaz1985]

Overall it's not a bad run of temps tonight especially for England & Wales

 

Tomorrow...

 

 

Wednesday....

 

 

Thursday it cools off a bit but becomes warm again below on Friday but again only for England & Wales and parts of N Ireland

 

Edited September 23, 2013 by Gaz1985

[mushymanrob]

i dont think many will like the general outlook, which generally is looking largely cloudy, but when it breaks overnight fog will be an issue, largely dry, but light patchy rain/drizzle might afftect some areas, warm - average - warm - average - warm - average as two more pulses of warmer continental air is expected to be drawn up over us over the next week or so.

 

the apparent lack of sun, or low levels of sun, plus no extremes and quite alot of grey overcast skies isnt what most weather enthusiasts would like to see, but thats appears to be whats on offer for many for a while.

 

ok, nowt technical there, but i cant be enthused about degrees of greyness!

[Captain Shortwave]

ECM is interesting this morning, it's building the high closer to us, in fact it will probably keep the East dry

[Frosty.]

The Fax chart for saturday shows a showery trough pushing in from the southwest and the airmass across the uk still looks warm and humid with the air sourced from southern europe, it suggests bands of heavy rain and heavy showers pushing slowly northeastwards across southern and central areas with a risk of thunder but some areas drier and brighter, especially further northeast where there is less trough influence although probably a lot of misty low cloud around too, but across the southern half of the uk there is a risk of torrential rain with local flooding.

Edited September 24, 2013 by Frosty.

[ANYWEATHER]

i dont think many will like the general outlook, which generally is looking largely cloudy, but when it breaks overnight fog will be an issue, largely dry, but light patchy rain/drizzle might afftect some areas, warm - average - warm - average - warm - average as two more pulses of warmer continental air is expected to be drawn up over us over the next week or so.

 

the apparent lack of sun, or low levels of sun, plus no extremes and quite alot of grey overcast skies isnt what most weather enthusiasts would like to see, but thats appears to be whats on offer for many for a while.

 

ok, nowt technical there, but i cant be enthused about degrees of greyness!

And of course the growing potential of some thundery downpours too......