Model Output Discussion - Spring 5th March Onwards 6z--->

[Frosty.]

Here comes the Azores high on Ecm 12z..looking very good.

Edited March 12, 2015 by Frosty.

[Cloud 10]

Worth noting that today's updates from GFS and ECM both have the MJO heading into phase 8,with the ECM then taking it into phase 1.

 

GFS..  ECM..

[Polar Maritime]

The GFS maintains the cool theme, As winds swing a more Pm N/Wly driving fronts S/E bringing bouts of wet unsettled weather. With a wintry mix for Scotland.

 

[Frosty.]

I'm pleased with the 12z output this evening, the ukmo, gem and ecm all build the Azores high into the UK next week, the ecm shows a strong ridge later in the run to keep control, I think 3 out of 4 is very good. :-)

[seaside 60]

Worth noting that today's updates from GFS and ECM both have the MJO heading into phase 8,with the ECM then taking it into phase 1.

 

GFS..NCPE_phase_21m_small.gif  ECM..ECMF_phase_51m_small.gif

Didn't I read on here earlier this week not to take any notice of these, due to major westerlies somewhere, that has produced an inflated reaction.

Having seen this quoted all this winter, most of it never came true.

Surely its all model based and if anything to go by the state of the model runs at the moment ( and the last few months) I think we should go back to the1960's style weather forecasting......

It cant be any worse.

[johnholmes]

IF the NOAA 6-10 is to be believed and it has been trending towards this then a Greenland ridge is a distinct possibility in the 6-10 day scale?

The air over N Scotland is sourced from the north of Canada and that over southern England from not much further south.

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

[ANYWEATHER]

A rather cold outlook for the next few days , I think cloud cover will be a problem, but a cold easterly will bite a little over the weekend , mainly dry albeit some wintry snizzle at times. A very messy mix next week, no detail for the weather on a day to day format will not be possible ,just stay in tune with the latest....  PS ....Phone a friend

Edited March 12, 2015 by ANYWEATHER

[johnholmes]

 I think we should go back to the1960's style weather forecasting......

It cant be any worse.

You mean 2-3 days ahead at most?

[damianslaw]

GFS out on its own today, with ECM, UKMO and GEM going for the high pressure overhead scenario next week, with a surge of heights from the azores building across the country and generally maintaining a more settled outlook, though northern parts will be under the influence of the atlantic somewhat with weak atlantic frontal attacks.

 

Longer term - lots of projected changes over northern hemispheric base state with the PV forecast to split and strong heights set to develop over the Poles, a good solid base state for potential colder outlook as we end the month and move into April.. much will depend on the position of the Jetstream and where heights over the Pole transfer.

[Frosty.]

I think we should go back to the 1960's style weather forecasting......

It cant be any worse.

Things haven't changed much have they :-)

[Cloud 10]

Didn't I read on here earlier this week not to take any notice of these, due to major westerlies somewhere, that has produced an inflated reaction.

Having seen this quoted all this winter, most of it never came true.

Surely its all model based and if anything to go by the state of the model runs at the moment ( and the last few months) I think we should go back to the1960's style weather forecasting......

It cant be any worse.

 

The MJO can be a useful forecasting tool when it is in a high amplitude as it is at the moment.

 

Cohen's blog posted further up the page is well worth a read as it explains  the large changes underway across the Northern hemisphere,which probably accounts for the volatility of the model output.

[seaside 60]

Things haven't changed much have they :-)

Proper forecasters in those days....

Having said that I pose a serious question.

I wonder how those guys from those days would fair with today's technology.

[seaside 60]

The MJO can be a useful forecasting tool when it is in a high amplitude as it is at the moment.

 

Cohen's blog posted further up the page is well worth a read as it explains  the large changes underway across the Northern hemisphere,which probably accounts for the volatility of the model output.

Thanks for the reply.

Playing devils advocate here.

Dont you think that the models seem to have been very inconsistent in recent times.

Also do you think there is possibly  to much info available with ridiculous future timescales being forecasted.

When in fact it is more or less only a less than 50% chance of them being right even with a 10 day or less timescale.

[johnholmes]

Proper forecasters in those days....

Having said that I pose a serious question.

I wonder how those guys from those days would fair with today's technology.

That first comment is rather unfair on the professional forecasters. All are trained in much the same way as in the 1960's but with an emphasis on how to use that training to interpret computer output.

Using what have become known as teleconnections is a part of that for forecasts beyond 6-10 days. The MJO is one such feature but care is needed using it as with any model output and it has to be used along with every other available output. A trained forecaster then assesses the most likely outcome, this takes years of experience. So care need to be taken in judging forecast outputs between a professional and an amateur, good as some are. As an ex forecaster I would say that forecasting has improved in just about every time scale. In the 60's there were no computers and basic meteorology was used to forecast. The complexities of weather forecasting are so huge than no human can even attempt without a computer anything beyond about 3 days. Computers are enabling more and more accurate forecasts to be issued for 3-10 days ahead with increasing but SLOW improvements out a bit beyond that. it depends how much detail you expect at time scales beyond about 3-7 days? Even closer trying to predict rainfall amounts, when, where, still causes problems even at 12-24 hours. Add in will it snow with a further 7 or 8 variables and that is down to less than that.

Hope that helps explain  some of the problems so don't be too hard on forecasters, professional or amateur.

Edited March 13, 2015 by johnholmes

[IDO]

An inevitable but rather delayed eureka moment from the GFS with the op now showing the HP dominated weather extending out till D10:

 

 

 

Of course it is behind the curve and no doubt has overdone the pressure rise and longevity so probably best to keep with the GEM and ECM for the moment.

 

GEM stalls the high further west this morning allowing the east to be on the periphery of the lower heights in Europe, but mainly settled for most:

 

 

 

ECM has also adjusted like the GEM with a similar forecast:

 

 

 

No point looking beyond D8 on the GEFS as at that time they are still showing large spread with no discernible pattern:

 

 

Looking at the ECM D10 NH profile nothing to raise interest here apart from the PV showing signs of becoming less of a driver as would be expected in late March:

 

 ditto GEM: 

 

The bias corrected GEFS MJO still showing the signal de-amplifying in phase 7: 

 

In the shorter term feeling cold in the east/SE this weekend with "feels like" temps around 3c at best with lots of cloud. As the hi res models predicted some hill snow with the front today as it stalls and moves back west. 

 

 

[Frosty.]

Cross model support now for the Azores high to build into the UK by around the middle of next week, the Gfs was the missing piece from the jigsaw yesterday but the op is very bullish about it this morning. Next week would see a gradually improving picture with increasing amounts of sunshine and light winds, becoming pleasant by day but cold at night with slight air frosts under clearing / clear skies.

Edited March 13, 2015 by Frosty.

[Gibby]

HERE IS MY LATEST ANALYSIS USING DATA SUPPLIED BY THE NWP OUTPUT COVERING 5 OF THE WORLDS MOST POWERFUL WEATHER COMPUTERS ISSUED AT 08:00 ON FRIDAY MARCH 13TH 2015.

 

THE CURRENT GENERAL SITUATION A front across Central Britain this morning will weaken and move West with a cold and fresh Easterly wind establishing across the UK.

 

http://www.wetterzentrale.de/pics/Rtavn001.gif 

 

MODELS-2 WEEK HEADLINE A lot of dry weather with some sunshine and just occasional rain especially at first in the South and in the North later. Temperatures will be close to average or a little below overall.

 

THE GFS JET STREAM ENSEMBLE FORECAST The Jet Stream Ensemble Forecast shows the the main thrust of the flow moving North across the Atlantic, Iceland and the Norwegian Sea. Meanwhile a Southern arm over Spain and Portugal blows for a time before the Northern hemispheric jet flow pattern becomes more confused and disorientated late in the period.

 

http://www.netweather.tv/index.cgi?action=jetstream 

 

GFS OPERATIONAL The GFS operational run today shows a lot of High pressure based weather, firstly over Europe giving the UK a spell of cold east winds and later over the UK with more sunshine, lighter winds and night frosts most likely at that time. the pattern looks more unsettled later with rain at times as Low pressure gradually takes at least temporary control over the UK.

 

http://www.wetterzentrale.de/pics/Rtavn1441.gif

 

http://www.wetterzentrale.de/pics/Rtavn3841.gif 

 

THE GFS CONTROL The GFS control run is somewhat different as the cold East then SE flow across the UK looks like lasting for much of next week with an increasing threat of unsettled weather creeping into Southern and later Central areas with rain or even sleet at times in places. Its not until a ridge collapses SE across the UK later in the period that a spell of equally chilly but unsettled weather under West or NW winds bringing spells of rain and wintry showers across the UK.

 

THE GFS CLUSTERS There is a large differentiality between the members of the GFS pack this morning in where we will be synoptically in 2 weeks time. High pressure is likely to be towards the South and SW of the UK by then but what is at disagreement is the influence of Low pressure to the North of the UK and how much influence affects the British Isles.

 

http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=euro&MODELL=gefs&MODELLTYP=2&BASE=-&VAR=cpre&HH=372&ZOOM=0&ARCHIV=0&RES=0&WMO=&PERIOD=

 

UKMO UKMO this morning shows the ridge from the East holding control early next week with the cold East wind lasting at least to the middle of the week across the South as High pressure builds over the North. rather cloudy skies with light showers look likely before more generally dry and perhaps brighter conditions feed South later next week.

 

http://www.wetterzentrale.de/pics/Rukm1441.gif 

 

THE FAX CHARTS The Fax Charts follow the theme of the operational well with a well established High well to the NE of the UK with a complex and slack Easterly flow across the UK with weak disturbances feeding West at times.

 

http://www.weathercharts.org/ukmomslp.htm#t120.

 

GEM GEM today shows the High pressure over Europe gradually transferring its influence from Europe to lie over the UK for a time and then further West onto the Atlantic with a chilly Northerly influence setting up to some extent across the UK later with perhaps slightly less settled conditions too.

 

http://www.wetterzentrale.de/pics/Rgem2401.gif 

 

NAVGEM NAVGEM differs to GEM and relaeases the continental High pressure's influence across the UK  next week in return for Low pressure edging in from the NW albeit slowly to leave all areas under cyclonic winds at the end of the period with wind and rain at times.

 

http://www.wetterzentrale.de/pics/Rnvg1681.gif.

 

ECM ECM this morning shows a complex and slowly changing High pressure based pattern over the next week. The winds will be maintained largely from an Easterly source with rather cold conditions persisting, especially in the South. High pressure developing close to the North later next week gives dry and fine weather ahead of a fall in pressure from the North at the closing days of the period with wind and rain edging South. 

 

http://www.wetterzentrale.de/pics/Recm2401.gif

 

ECM 10 DAY MEAN The 10 Day Mean Chart this morning is slowly edging towards a more Atlantic based Westerly feed with rain at times as we approach the 10 day mark replacing the High pressure based pattern beforehand.

 

http://www.wetterzentrale.de/pics/Reem2401.gif 

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The collapse of the European High next week is well supported but the evolutions thereafter continue to show no concistency today.

 

31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKM & ECM The current verification statistics for the past 31 days shows ECM leading the way at 3 days with 97.8 pts followed by UKM at 97.4 pts and GFS at 96.7. At 5 days ECM  continues to lead the field at 91.3 pts over UKMO at 89.3 pts and GFS at 86.0. At 8 days ECM remains the leader with 68.7 pts over GFS's 62.9 pts. Then at Day 10 ECM retains superiority at 51.1 pts over GFS at 46.3. 

 

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day3_PMSL_MSL_G2NHX.png 

 

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day5_PMSL_MSL_G2NHX.png

 

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day8_PMSL_MSL_G2NHX.png

 

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day10_PMSL_MSL_G2NHX.prig

 

 

MY THOUGHTS There is good support in the short term model runs this morning for a spell of chilly Easterly winds, rather cloudy skies and light showers, perhaps wintry in places over the next 4-5 days as High pressure to the NE of the UK remains dominant. As next week passes it still looks like a rise of pressure will also occur to the West and NW of the UK feeding drier and clearer conditions with more sunshine and frosty nights late next week. From that point on though conditions look much more sceptical and uncertain with a variety of options on the table, most leaning towards a gradual return to more Atlantic based weather though this in itself doesn't look like being the mild and changeable variety with most of the options I've seen this morning supporting this theme looking like bringing quite cold air from the North with it, especially over the North. The details of the longer term this morning is too hard to call so the best summary I can give is for most folks to have to look forward to a spell of rather cold weather under a lot of cloud and a few showers, these across the South and especially early next week. Later in the week more sunshine could develop with perhaps more in the way of frost by night before a more unsettled patten may develop from the North late in the period.   

 

Issued at 09:00 Friday March 13th 2015

[seaside 60]

That first comment is rather unfair on the professional forecasters. All are trained in much the same way as in the 1960's but with an emphasis on how to use that training to interpret computer output.

Using what have become known as teleconnections is a part of that for forecasts beyond 6-10 days. The MJO is one such feature but care is needed using it as with any model output and it has to be used along with every other available output. A trained forecaster then assesses the most likely outcome, this takes years of experience. So care need to be taken in judging forecast outputs between a professional and an amateur, good as some are. As an ex forecaster I would say that forecasting has improved in just about every time scale. In the 60's there were no computers and basic meteorology was used to forecast. The complexities of weather forecasting are so huge than no human can even attempt without a computer anything beyond about 3 days. Computers are enabling more and more accurate forecasts to be issued for 3-10 days ahead with increasing but SLOW improvements out a bit beyond that. it depends how much detail you expect at time scales beyond about 3-7 days? Even closer trying to predict rainfall amounts, when, where, still causes problems even at 12-24 hours. Add in will it snow with a further 7 or 8 variables and that is down to less than that.

Hope that helps explain  some of the problems so don't be too hard on forecasters, professional or amateur.

Thanks for your reply John,

Expanding a bit on the "forecasters of those days", 

I might be wrong but in times gone by you were a meteorologist who became a TV weather presenter.

While there are the same today I feel that many of today's presenters are just that, they present the weather, rather then being a meteorologist.

[mushymanrob]

While there are the same today I feel that many of today's presenters are just that, they present the weather, rather then being a meteorologist.

 

not on the bbc.... i believe the bbc employ people from the met office, or who have had training. itv employ presenters.

[seaside 60]

An inevitable but rather delayed eureka moment from the GFS with the op now showing the HP dominated weather extending out till D10:

 

gfs-0-120 (1).png gfs-0-240 (17).png

 

Of course it is behind the curve and no doubt has overdone the pressure rise and longevity so probably best to keep with the GEM and ECM for the moment.

 

GEM stalls the high further west this morning allowing the east to be on the periphery of the lower heights in Europe, but mainly settled for most:

 

gem-0-150.png gem-0-240 (23).png

 

ECM has also adjusted like the GEM with a similar forecast:

 

ECM1-120 (4).gif ECM1-216 (10).gif

 

No point looking beyond D8 on the GEFS as at that time they are still showing large spread with no discernible pattern:

 

Meteociel_-_Panel_GEFS 4.png

 

Looking at the ECM D10 NH profile nothing to raise interest here apart from the PV showing signs of becoming less of a driver as would be expected in late March:

 

ECH1-240 (4).gif  ditto GEM: gemnh-0-240 (6).png

 

The bias corrected GEFS MJO still showing the signal de-amplifying in phase 7: ensplume_full (6).gif

 

In the shorter term feeling cold in the east/SE this weekend with "feels like" temps around 3c at best with lots of cloud. As the hi res models predicted some hill snow with the front today as it stalls and moves back west. 

Last night Cloud 10 stated that it was phase 8 going into phase 1.

Is this because the models have changed or different peoples interpretations.

A genuine question as the MJO has been quoted so much this year.

Edited March 13, 2015 by seaside 60

[Summer Sun]

Better late than never GFS has finally woke up and followed what UKMO and ECM have shown for the past 2 days or so

 

[March Blizzard]

not on the bbc.... i believe the bbc employ people from the met office, or who have had training. itv employ presenters.

 

In the North West we occasionally have a south London fashion designer presenting our weather, this is on the BBC by the way. I'll eat every hat ever made in Stockport if she's a qualified meteorologist...

 

Anyway, apologies for being off topic.

[Polar Maritime]

Ok back to Model Output Discussion please, Thanks.

 

PM.

[IDO]

Last night Cloud 10 stated that it was phase 8 going into phase 1.

Is this because the models have changed or different peoples interpretations.

A genuine question as the MJO has been quoted so much this year.

Hi.. I usually post the bias corrected GEFS MJO as that appears to be more reliable at times. Very complicated at the moment with other factors that maybe pushing the high amplification phase 7. Also we have several Cyclones in the Pacific possibly disrupting the wave pattern and we wait to see if they will force a pattern change:

https://twitter.com/anthonywx/status/576320632012578816

Edited March 13, 2015 by IDO

[Frosty.]

There will be some snow on high ground today, the northern pennines and Cumbria as a front stalls down the spine of the UK. Turning colder this weekend.