johnholmes
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Posts posted by johnholmes
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Drty but mostly cloudy, a low of 5.1C, at about 0100 before it turned cloudy, now 7.1C
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The NOAA output supports that idea k, the 6-10 is still solid in the block with actual contour ridge and marked +ve heights but the 8-14 is a marked change on the last issue I have stored, 2 days ago. If it remains with this theme then the idea of blocking for 7-8 days or so slowly changing to a 500mb flow from about WSW encroaching from the NW looks about right. Temperatures recovering to give mean values about or a shade above normal for late October. Also likely to become less settled over all parts, spreading from the W/NW.
NOAA link below
http://www.cpc.noaa.gov/products/predictions/610day/500mb.php
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This thread bodes ill for the model thread when we get the first 528DM line within reindeer distance of Scotland!
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Dry but cloudy, showers late evening, a low of 6.8C
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Not quite a ground frost, curreent low is 3.9C, clear sky, no wind, and 3.9C is the lowest since 28 April.
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Some striking model output on offer so far today, which is a nice progression from the fairly uninspiring charts of the past couple of days. This is largely down to the high looking to have more of a chance of retrogression west of the UK for a time... but what are the odds that the changes to a more zonal regime not only manifest but do so at just the right time to topple the high before anything much comes out of it
not if the anomaly charts are anywhere near correct between 6 and 14 days!
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Beautiful from mid morning and practically cloudless this afternoon, very little breeze in my back garden,max of 16.4C and saw XH558 on finals into Doncaster, maybe another flight before it finishes?
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both very similar there john. have any other years seen this type of pattern persisting through october?
sorry my memory is not up to that sort of filing, someone else may be able to say though. It is different to what we saw at this time last year. Caution though, for you or anyone else, trying to match October patterns to the coming winter. The huge computer facilities at NOAA, UK Met and ECMWF have never been able to get enough to be able to use this, on its own, as any indicator. The issue of 3 month or more forecasting is still in its infancy and it may well take decades before anything shows usable results in my view. That said the model output from UK Met IF looked at objectively is not bad. Well that is my opinion over the last couple of autumn into winter periods. So long as folk look at it like I say objectively and as a background idea.
just read the post by chio above, should have done this before I posted, very interesting comments there.
apologies to admin and mods if this should really just have a link after the first sentence and be put in the winter thread?
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as promised the EC-GFS output this morning, both about the same as each other in broad terms and both pushing the idea of blocking over/close by UK
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Question..
As we head further into the realms of winter, and IF that gigantic high in the Atlantic sits there and sways west east North south for the coming few months.. IF it does push North into Greenland SAY at the end of October into November how long can a Greenland high realistically last with the correct set up..
normally not beyond 7-10 days, often less, very infrequently 2 weeks, on past climate/weather data
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Dry, no wind, mostly cloudy with a mix of Sc and Ci, a low of 8.7C so qute a mild start
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That surface chart does not really fit the 3 anomaly charts I use. These suggest the upper high being centred W of the UK with any upper trough to the east over Europe. What is possible, but not showing, is for the pattern to allow colder air to filter round the northern flank. Even so the heights look fairly 'high' as they are originating (for far south of the UK) from northern California and just south of the Gt Lakes. This would not suggest any markedly colder weather in the next 2 weeks to me?
links
http://www.cpc.noaa.gov/products/predictions/814day/814day.03.gif
will drop the latest ECMWF-GF in when they arrive this morning, along with anycomment if they do not look much as yesterday morning's output.
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Thick fog with sky obscured, no wind, and a low of 4.5C
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Mostly cloudy with no breeze, the low was at 2300 last evening before the cloud appeared, 7.8C
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The GEFs anomalies tonight continue with the theme of the last few days. The 6-10 has ridging from the SW over the UK, LP Canada giving a surface analysis of a swathe of HP from the south west through to Scandinavia. The actual detail Depends on where HP cells settle but generally temps below average, In the 11-15 period there is less amplification and the influence of the HP weakens leading to more zonal flow with temps average, Nothing sinister in the woodshed. NOAA would appear to be less inclined to take the zonal option
I would be inclined to take the NOAA version as the most likely!
I actually reckon that some ways this could make it more tricky to anticipate the overall trend beyond a week's range
hence why, in my view, I believe the best option for basic upper air ideas and from that the general idea of the 'type' of weather is the 500mb anomaly charts, best are NOAA and then ECMWF-GFS IF it tends to agree with NOAA. Having said that over the past 9 months or so the EC-GFS variant has, at least, 4 times in that period been the leader rather than led by NOAA for the correct upper air pattern at 6-10 days.
Just my opinion and you and other may well disagree with my ideas.
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this is probably appropriate in this thread?
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.pdf
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That is true, but being somewhat pedantic, could we say they do take past weather into account when the algorithms are tweaked?
again no to the best of my knowledge but perhaps an e mail to UK Met might reveal, if their web site does not, exactly what goes into their model?
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Beautiful morning, less than 1-2/8 CuSc until 45 minutes ago when a lot of shallow Cu developed, no wind, sunny what more could one ask for in October?, T=15.6C
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yep there most certainly was i wonder if models use winter 09/10 in there data when producing outputs.
nope
simply run with current actual weather as they always have done
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Cloudless with no wind, a low of 5.4C
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For those interested here's today's report link:-
http://www.norton-radstockweather.co.uk/Model-Analysis(2859336).htm
copied below
THIS PAGE PROVIDES THE LATEST ANALYSIS FROM THEWORLD'S MOST POWERFUL SUPER WEATHER COMPUTERS
CALCULATING THE UK WEATHER FOR UP TO 15 DAYS
AHEAD OF THE PRESENT
UPDATED DAILY
HERE IS MY LATEST ANALYSIS USING DATA SUPPLIED BY THE NWP OUTPUT COVERING 5 OF THE WORLDS MOST POWERFUL WEATHER COMPUTERS ISSUED AT 09:00 ON WEDNESDAY OCT 7TH 2015THE CURRENT GENERAL SITUATION Low pressure will move away out into the North Sea today followed by a ridge of High pressure moving East into the UK today and tomorrow.
http://www.wetterzentrale.de/pics/Rtavn001.gif
CURRENT SNOW LYING UK AND NORTHERN HEMISPHERE There is currently no snow lying in the UK with the freezing level at just under 5000ft in Western Ireland and close to 8000ft in eastern England.
http://www.snow-forecast.com/maps/dynamic/uk
http://www.natice.noaa.gov/pub/ims/ims_gif/DATA/cursnow.gif
MODELS-2 WEEK HEADLINE Changeable with a little rain at times but with some lengthy dry and settled periods developing again too especially later.
THE GFS JET STREAM FORECAST The GFS Jet Stream Forecast shows he flow split to the North and South of the UK for the next few days. The flow becomes weak next week and gradually realigns well to the NW of Britain before diving South across the UK in Week 2 in association with Low pressure to the East and NE.
http://www.netweather.tv/index.cgi?action=jetstream
GFS OPERATIONAL The GFS Operational Run today shows the weather improving now as High pressure builds across the UK which first to the East and NE of the UK before High pressure in the Atlantic takes control in Week 2 with a chilly North or NW flow towards the end of the run. Rainfall amounts look very limited for all of the UK throughout the period of the run today.
http://www.wetterzentrale.de/pics/Rtavn1441.gif
http://www.wetterzentrale.de/pics/Rtavn3841.gif
THE GFS CONTROL The theme of the GFS Control Run shows much very similar conditions with High pressure developing as I type and persisting in one shape or form across or near the UK until towards the end of Week 2 when the Atlantic breaks through with some rain and wind.
http://www.meteociel.fr/modeles/gefs_cartes.php
THE GFS CLUSTERS(14 Days) The GFS Clusters in 14 days has a majority bias towards High pressure lying close to or to the West and SW of the UK with fine weather for most of the UK.
UKMO UKMO today shows High pressure building across principally over the North over the weekend and start to next week with fine and dry weather there while the South comes perilously close to being influenced by Low pressure to the South with a chilly Easterly flow and the risk of some rain in places.
http://www.wetterzentrale.de/pics/Rukm1441.gif
THE FAX CHARTS The Fax Charts this morning shows High pressure developing to the NE of the UK with an east or SE flow developing across the UK. Low pressure lies to both the South and NW early next week with most of the rain bearing troughs associated with this held mostly at bay at the 5 day time point.
http://www.weathercharts.org/ukmomslp.htm#t120
GEM GEM also builds High pressure back across the UK from the North-east later this week with some fine and settled weather for many for a time. Then through next week the trend is for High pressure to decline slowly and Low pressure with rain to edge up across the UK from the SW towards the end of the week.
http://www.wetterzentrale.de/pics/Rgem2401.gif
NAVGEM NAVGEM looks a lot like UKMO this morning with North is best in regard to fine and settled weather as a ridge of High pressure persists across these areas next week. Meanwhile Low pressure to the South may be close enough to being a keen easterly breeze, cloud and some rain at times up into the far South.
http://www.wetterzentrale.de/pics/Rnvg1681.gif
ECM ECM this morning has the building of High pressure too through the end of the week and weekend. the axis of this is a little further South than the rest of the output maintaining fine weather for all in light winds. Later in the run the ridge relaxes South and allows Atlantic westerly winds and rain to slowly feed down from the NW.
http://www.wetterzentrale.de/pics/Recm2401.gif
ECM 10 DAY MEAN The ECM 10 Day Mean Chart from last night indicates the UK lying in slack pressure between High pressure both to the SW and NE with the weather likely to be mostly quite benign across the British Isles but with some rain at times towards the North and West and perhaps elsewhere in more isolated form.
http://www.wetterzentrale.de/pics/Reem2401.gif
NOTABLE TREND CHANGES FROM PREVIOUS RUNS There is still good agreement now on a largely fine and benign spell of weather developing again across the UK from later this week once the demise and final resting place of ex hurricane Joaquin is established.
31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The verification Statistics of GFS, UKMO and ECM show at 24 hours ECM tying with UKMO at 99.5 pts with GFS closely behind at 99.3 pts. At 3 days ECM is leading with 97.0 pts to UKMO's 96.9 pts while GFS lags behind at 95.8 pts. At 5 days ECM leads with 87.8 pts to UKMO at 86.8 pts then GFS at 83.7 pts. Then at 8 Days ECM still leads at 58.3 pts over GFS's 50.1 pts. Finally at Day 10 ECM leads GFS at 35.2 pts to 33.3 pts.
http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day1_PMSL_MSL_G2NHX.png
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.png
MY THOUGHTS The models have finally settled on the final resting place of ex hurricane Joaquin and it seems we can now rest assured that it will remain out of harms way to both the NW and South while the UK settles into a period of benign and quiet weather as High pressure builds from both the NE and SW. Low pressure looks like remaining to the South of the UK for quite some time delivering a chill Easterly breeze across the South with some output indicating that Low pressure could be close enough to give a little rain to Southernmost parts. then in the latter stages of the two week period High pressure seems to hold on as the most governing factor across the UK, maybe slipping a little in dominance later as the Atlantic finally wakes up again. Nevertheless, once more today there are no major weather problems looking likely over the coming few weeks and a lot of the weather for outdoor activities look's generally OK given the time of year it is.
WORST CHART OF THE DAY 00z RUN
http://www.wetterzentrale.de/pics/Rgem2401.gif
I was struggling to find a particularly bad chart today but the GEM 10 day chart would ensure a cool and wet day for much of the UK especially the South as Low pressure moves up from the SW.
BEST CHART OF THE DAY 00z RUN
http://www.wetterzentrale.de/pics/Recm1441.gif
Contrastingly, spoilt for choice in the best chart series with the GFS 144hr chart representative of many as High pressure is shown well established over the North of the UK with fine and settled weather for all.
Next update from 09:00 Thursday Oct 7th 2015
Quick question Gibby, took me 20 secs, so why do you not do the same please, rather than the link to your web site?
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That's an interesting article; never realised these differences in data assimilation existed.
One current weakness in the GFS relative to the ECMWF, noted in the New York Times article, is its technique for data assimilation (bringing as many observations as possible into the starting point of a model run). ECMWF employs a four-dimensional data assimilation technique, while the GFS uses a 3D technique. The fourth dimension is time: the 4D system allows data from satellites and other sensors to be woven into a model run over multiple time steps, rather than being injected into the model at a single time step. In this and several other ways, including the ability to draw on a wider range of observations, the ECMWF data assimilation appears to give it the edge. A 4D data assimilation system is now being developed for the GFS, perhaps to be incorporated within the next year.
Run data sources for the ECM.
Mind bogglingly extensive!
Just a 'bit' different to the days when surface observations on land and sea were, along with 6 hourly radio sonde data, the only data available at each main synoptic hour. Those were the days!
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Raining again but not had much overnight, a low of 12.2C
Model Output Discussion 18z 30/09/15
in Forecast Model Discussion
Posted
Can we try and keep posts in their correct threads please? Several above are more suited to the winter thread rather than the model, or am I in a minority here? Nothing wrong with the discussion though.