Model Output Discussion

[pyrotech]

Don't know what to make with gfs at the moment , It has been performing quite badly on tropical depression two as has ukmet. Obviously If these tropical systems travel north eastwards it has an impact on our setup . Best forecast at the minute for the next 5 days would be continuing unsettled in the north and west with showers or longer spells of rain and strong winds at times in the far north west. Remaining more settled in the south with showers few and far between although it may get rather cloudy at times especially so in the north midlands. Temps ranging from 24 at times in the south to 12-16 in the north and west.

A little nip in the air tonight which reminds me that winter is not that far away . Although I do worry that if the Jet finally goes north as we head towards winter that it would ruin our snow chances , although it would probably mean dry and frosty over christmas which alot of people will be happy with . If I was a betting man i'd go for a very cold and snowy late winter mid Jan/feb/march.

Chris

Could not agree more.

My reasons are due to solar minimum this has an ongoing effect which starts after a normal minimum ( or max). There is a delay before the effects but we have passed timescale of normal minimum and its deeper. The chances of an 80s style winter are getting greater. ooops that will make the Met office winter forecast about as accurate as their BBQ summer one.

The post before mentioned the effect on the Jet, This seems to follow the slight changes in the North Atlantic conveyor ( drift). Would make sense as the jet is caused by warm air from tropics meeting the cold air at the poles.

I think this years model output discussion will be very busy with Autumnal deep storms causing major discussions as we go towards the last quarter of 2009 and then massive discussions on Snow and cold for the coming winter.

On the models they really sem to all be struggling to get anything resembling accurate beyond 5 days, But it is a pretty unusual setup world wide. Lots of storms in pacific area and still waiting for first atlantic tropical storm( This time last year we had 6 named storms) Things seem to be livening up slightly it the Atlantic and this may allow the normality to effect the models giving a similarity in the fi period.

At least its interesting due to its unusual behaviour but there does seem to be a pattern arising as i predicted of more like 80s winters and wetter summers.

[William of Walworth]

there does seem to be a pattern arising as i predicted of more like 80s winters and wetter summers.

It is HUGELY open to debate (and in a different thread, too!!) to suggest that we are set for a recurring pattern in future years of wetter summers (I think the 80s winters thing -- you mean colder? -- is open to question as a pattern too).

Call me bad news resistent, but I refuse to accept as a given that three poor (or at best average) summers -- 2007, 2008 and 2009 -- mean that we are locked into similar summers for the foreseeable few years.

Wouldn't take much shifts in the detail for 2010 to turn out a prolonged warm dry and summery one for the UK. NO-ONE on here can rule this out ....

At least as plausible is the idea that current patterns are highly volatile and unpredictable and changeable. Leaving the windows of possibilitie sopen that next summer could end up very different.

As rightly said by someone above, we are still very unclear beyond the next few days even ....

Death to inevitablist doomsayers say I!

Edited August 13, 2009 by William of Walworth

[Nick.F]

The atmospheric system is too vast, too complex and too chaotic for there to be any link between this year's weather (or the last year and the year before) and next year's. Countless factors coming in to play.

There may be trends (but there is no evidence that the last three years indicate any sort of trend), but it was only 6-8 years ago the the world was set alight by claims of rising temps, droughts, Mediterranean summers, temps regularly over 40c - it hasn't happened. We do not have enough information to scientifically or definitively identify such trends.

There could be a massive "ejective" volcanic eruption somewhere in the next year, like those at Mt Pinatubo or Novarupta, which would effect the global weather patterns for months.

It is also important to remember small differences in location can make tremendous differences to the experience for weather. Here in NE Essex, this summer has been generally quite nice; not too hot, not too cold, mostly sunny, dry and warm. These conditions bear little relation to what most people have experienced. So for me this summer has not been anything like 2007/2008.

[pyrotech]

It is HUGELY open to debate (and in a different thread, too!!) to suggest that we are set for a recurring pattern in future years of wetter summers (I think the 80s winters thing -- you mean colder? -- is open to question as a pattern too).

Call me bad news resistent, but I refuse to accept as a given that three poor (or at best average) summers -- 2007, 2008 and 2009 -- mean that we are locked into similar summers for the foreseeable few years.

Wouldn't take much shifts in the detail for 2010 to turn out a prolonged warm dry and summery one for the UK. NO-ONE on here can rule this out ....

At least as plausible is the idea that current patterns are highly volatile and unpredictable and changeable. Leaving the windows of possibilitie sopen that next summer could end up very different.

As rightly said by someone above, we are still very unclear beyond the next few days even ....

Death to inevitablist doomsayers say I!

Please move if in wrong area

Got to agree with you if based on 3 years

BUT

I predicted Storms ( DEEP LOW PRESSURE SYSTEMS) in the nineties followed by a gradual return to Eighties style winters. Wet humid summers ( wish we had eighties summers )

All this back in 1985

seems to be heading pretty much as expected

Climate change has been around for millions of years, well before human intervention.

The solar cycle has one of the biggest effects on weather and not something the models can cope with very well.

No one was able to forecast this solar minimum, and there is alot of disagreement about the effects.

BUT the North Atlantic drift is more predictable due tu lots of available data. It effects us in North western Europe greatly and 1/10 of a degree is huge in its effects.

The great thing about the forum is that like the Models there is a difference of opinion, like the models none of us will be exactly right. Maybe some will resemble something like what happens.

I respect your reply but you, assumed i made that comment on 3 year basis. NO!

How the models will cope with the solar minimum and any effects i am not sure but to be honest all the Big models GFS, Ecm have struggled for weeks with anything more than 3 days. I can only see this getting worse as we head into a unpredictable winter, with maybe the solar min having effects on Snow or No Snow scenarios.

As respected members whose posts i have read in the past i take note of your critism.

Can i ask if any one has an opinion on which model seems to be consistantly more accurate over a 3 - 7 day period since mid July as i can not find any consistancy as they all seem to be struggling. Please post reasons why if you have found one better than others .

[NorthantsSnow]

The weather isn't looking too shabby next week for many southern, central and eastern areas. Could be a lot of sunny, warm (dare I say it even hot) weather about. Last chance saloon for summer 2009 perhaps, although personally I wouldn't rule out indian summer conditions in September.

Edited August 13, 2009 by NorthantsSnow

[mushymanrob]

is there any chance of that high pressure progged for early next week, to hold its position over to our east instead of slowly drifting into the continent? it would be great IF it did hold over denmark/germany and intensified....

oh well.... one can but hope!

[William of Walworth]

The weather isn't looking too shabby next week for many southern, central and eastern areas. Could be a lot of sunny, warm (dare I say it even hot) weather about. Last chance saloon for summer 2009 perhaps, although personally I wouldn't rule out indian summer conditions in September.

One can but hope x 2

[MP-R]

is there any chance of that high pressure progged for early next week, to hold its position over to our east instead of slowly drifting into the continent? it would be great IF it did hold over denmark/germany and intensified....

oh well.... one can but hope!

Wouldn't it just. Ideally we would have high pressure migrating towards us then settling for a ten day period before moving off eastwards pulling up hotter air for the Bank Holiday weekend then a bang on the 31st like 2005 and a return to the Atlantic in September when everyone has gone back to work and school and can;t enjoy any good weather. A perfect evolution.

I've noticed the rain forecast for Friday and the weekend seems to stay away from the south so perhaps not as abad as first thought with the south staying mostly dry with average temperatures. I do feel sorry for those who are going to get a soaking though this coming weekend. 24.7C and sunny here!

[The PIT]

Well the models started downgrading the settled spell at the beginning of the week and then started upgrading it again as the week went on. FI probably around T72 at the moment. We also still seem to have the constant downgrade of any low pressures within T96. This started last winter I wonder why.

[Thundery wintry showers]

ECMWF seems to be doing a much better job with these attempts at high pressure development than GFS at the moment, with the GFS 12Z falling into line with ECMWF, in suggesting just a brief interlude of drier warmer sunnier weather for the south-eastern third of Britain. GEFS ensembles also strongly back up this evolution.

[Eugene]

As ever any hot southerly plume is shunted eastwards, 19th to 21st not looking anywhere as hot as on August 11th GFS 12Z

[J10]

Some decent weather this week and this weekend is looking better further south, and the ensembles show drier weather for much of next week, however I can fully understand the despondency to the North West, we had this weather in July.

[damianslaw]

Have to say the models have been in fickle mood these past few days, as already stated, the synoptics earlier in the week were calling a downgrade in conditions for many by tomorrow, now it seems the low pressure and fronts are only really going to affect N Ireland and W Scotland, here in Cumbria we are forecast to be spared the worst - will be interesting to see what the situation is tomorrow and how far south and east the rain stretches.

Consequently I have little faith in the models at present, pressure patterns and longer term evolution is difficult to predict, attempts of heights building to the east could further intensify next week leading to a southerly airstream as low pressure becomes stuck in situ to the west, otherwise it will be the atlantic all the way, the azores high is a weak player at present with the jet in a more southerly position it isn't ever going to get a hold on us, best hopes longer term for settled warm weather is for heights to build further east over near continent.

One observation of this summer just like 2007 and 2008 has been the complete absence of the euro high, where has it gone? I haven't been following whats been happening in the rest of Europe this year, but there have been no reports of heatwaves etc, so where is the europe heat this summer? It must be somewhere??? Answers...

[mountain shadow]

Some decent weather this week and this weekend is looking better further south, and the ensembles show drier weather for much of next week, however I can fully understand the despondency to the North West, we had this weather in July.

It's worse than that, much worse...

This weekend is going to be awful and even looking further ahead to next weekend we have another LP lining up some wet, windy and depressing weather for the North West..

http://91.121.93.17/pics/Recm2161.gif

[chapmanslade]

It really is a tale of two halves this summer - with a perfectly average summer in the south and pretty grim at times in the north. Another nice day today at 24C which makes it 4.5 out of the last 6 being warm and sunny, and dinner outside again tonight (I'm not going to say how many BBQ's we have had for fear of riling our northern brethren).

Looks pretty much the same for the week ahead with much of the south faring pretty well. I'll be in France enjoying the 20C 850's predicted for much of next week leading to temperatures in the low to mid 30's. I'll blow as hard as I can to push it north, although it does look like there will be some heat in the south of the UK.

[NorthantsSnow]

Conditions look nigh on ideal for the start of the Northamptonshire Balloon Festival tomorrow with very light winds, relatively clear skies and good visibility. Unfortunately as the day progresses a moderate SWly wind is likely to develop with wind speeds potentially in excess of 14-15mph, casting serious doubt over Friday's evening lift and both of the lifts planned for Saturday. On Sunday conditions should improve with lengthy sunny periods and calmer winds but it's a knife edge situation that's changing all the time.

In 2008, only 3 of the scheduled 6 flights took place due to predominantly wet and windy weather. In both 2006 and 2007, only 2 flights went ahead. But 2005 was a better year, with 5 of the 7 scheduled flights taking place, including an extra one on the Thursday to mark 15 years of the festival. And in 2003, ideal conditions meant that 5 of the 6 planned lifts were successful.

[chionomaniac]

The MJO is now entering phase 1 as forecast.

http://www.bom.gov.au/bmrc/clfor/cfstaff/matw/maproom/RMM/phase.Last40days.html

This is due to an increase in tropical convection in the Indian Ocean as can be seen by the latest OLR maps.

http://www.bom.gov.au/bmrc/clfor/cfstaff/matw/maproom/OLR/m.3d.html

The tropical convection in this area is forecast to increase further leaving us in a stronger phase 1 amplitude orbit with a possibility of entering phase 2.

http://www.cpc.ncep.noaa.gov/products/people/wd52qz/mjoindex/index/diagram_40days_forecast_GEFS_membera.gif

As I have mentioned before, the MJO 500hPa anomaly composites for these phases are completely different to that of the GWO and the composites GP suggested a couple of days ago. I can't see the GWO signal being overridden currently ( certainly the models don't suggest that it will) but the stronger the MJO signal becomes the more influence it will have. The GWO suggests the possibility of a pressure rise from the south but a trough never too far away from the north ( possibility wet with warm/ hot humid weather), the MJO a ridge extending in from the west ( dry and ? sunnier) . GWO still edging it.

c

[Frosty.]

All the latest models look similar out to T plus 144 hours with a ridge set to transfer eastwards on monday and become absorbed into the main continental anticyclone by tues/wed. It looks a pretty fair/warm week for south-eastern britain but the dire summer is set to continue in the north west close to ever present low pressure. It will probably turn generally unsettled everywhere by later next week but high pressure to the south and east of the uk could hold on and keep the south east mostly rain free which would be good news for the test match although on second thoughts..

[mushymanrob]

tbh i dont agree that the ecm is outperforming the gfs regarding high pressure, the gfs was the first to pick out the 'nearly' event earlier this month, and next weeks mini warm spell. ok it initially overcooked the extent of the high, but nontheless it still spotted it.

nice bit if fi eye candy, a great big fat high sat on top of us! this will happen at sometime as im still very much expecting a lengthy settled/high spell in autumn.

[Frosty.]

This summer has flattered to deceive and the latest model runs continue the disappointing trend especially in northern and western areas with low pressure close by, the best weather restricted to the south and south east of england as usual. The ecm 00z is disappointing next week with lots of unsettled weather as a trough develops ahead of the main atlantic low, the gfs 00z is somewhat better with more ridging in the south keeping the bad weather further to the north/west, the ukmo 00z is probably the pick of the model runs so far today showing fine and warm conditions for central/southern & eastern england for most of next week.

[William of Walworth]

Well I'm in West Wales (Swansea) and heading for Devon early on Friday 21st for our last summer excursion (the fate-temptingly named 'Beautiful Days' festival -- and farcically so named the same weekend last year!). As you can guess I'm hoping the current UkMO modelling is the winner, GFS would be acceptable as well. But for us it's all about whether any driness/warmth in the South lasts right through til the 23rd and 24th, obviously this far out there's still considerable doubt about that.

I do feel sorry for anyone up in North Western parts though -- we had it pretty bad in most of Wales in July and for now the worst seems to be concentrating on areas somewhat further North.

[Thundery wintry showers]

tbh i dont agree that the ecm is outperforming the gfs regarding high pressure

Interesting you say that, because the latest runs (GFS 06Z, ECM 00Z) have brought the southerly plume back for midweek next week. The south-eastern half of Britain is down on the GFS as having two hot dry sunny days on Tuesday and Wednesday followed by thundery showers on Thursday, while ECMWF has also started to show something resembling a plume. Perhaps the GFS might not turn out to be as wrong as I thought? The 12Z runs today will certainly be of interest.

[Methuselah]

At last...A sliver of potential on the GFS.

Should it materialize (by no-means certain!) there could be a two-week spell of warmth; if not wall-to-wall sunshine???

My CET GUESS of 14.8(?) may have been a tad pessimistic??

[mushymanrob]

the 06z is a peach of a run throughout! doubt if just how much will happen but the 06z recently seems to be a much warmer 'better' run then the rather reticent 00z.

as for next weeks 'plume event'... well those in the south east might benefit by this glancing blow from the plume, but most of us will miss out... the settled anticyclonic first few days of next week is more or less 'in the bag', the big question is what happens next. a return to the atlantic? or a rebuild of pressure as the 06z suggests.

[Derp Patrol]

Well it looks like i'll miss out most of the settled weather we have been missing all summer when I go away next Thursday..

Anyway, my early thought on Autumn are that we will have an indian summer, with September being well above average temperature wise and quite dry.