Model Output Discussion - 1st August 00z---------->

[William of Walworth]

Lovely charts Frosty -- for those going away in early Sept, rather than the coming weekend! 

 

</grumpy to be heading away with wind and rain threatening from Thursday, while confined to home when the traditional September UK High might take over>

Edited August 18, 2015 by William of Walworth

[Methuselah]

The Gfs 12z shows an anticyclonic early September with high pressure building in and intensifying over the UK with max temps into the low 20's c but cool nights under clear skies, especially in the north. As for closer range, there are some occasionally dry, sunny & very warm and hot days across the s/e, the first of which is Saturday and then again at times next week but we are in for an unsettled spell with variable temperatures and sometimes breezy/windy but summery weather too, the southeast quarter of England has the best of it on this run with the northwest, as usual being coolest and most unsettled until the end of August.

lol Frosty. By the time that chart comes to fruition, we'll be having persistent frost and fog!      

[Roadrunner]

William I feel your pain. Typical isn't it that the weather sometimes seems to conspire to spoil anything that you're planning to do outside! I too am hoping for dry weather as we're off camping in East Sussex.

Only thing I can say is I've been following the GFS rainfall charts (I know some don't rate these but I've always found them most useful) and with each run and for the area I'm interested in it seems to be pushing the heavier rain more to the west. While this doesn't help you for where you are going, if this does keep adjusting then things may look better.

I am in no way an expert and still learning. Do enjoy this model watching, even though sometimes it is painful!

Edited August 18, 2015 by Roadrunner

[Frosty.]

lol Frosty. By the time that chart comes to fruition, we'll be having persistent frost and fog!      

Yeah you're probably right there Pete although I think the met office update today mentioned something about a generally settled spell at the end of August so perhaps the gfs 12z is on to something, at least I hope it is.

[Winter Cold]

Hmm unfortunately the last two GFS runs have been far above the mean in terms of pressure towards the end. Its highly unlikely at present that anything like that will happen. As you can see the 06z was a clear outlier at the end:

 

 

 

Better news for early next week though as the ECM and UKMO have watered down the low which I posted earlier with only the GFS now still showing a dart board. One to keep watching though

Edited August 18, 2015 by Winter Cold

[Methuselah]

Yeah you're probably right there Pete although I think the met office update today mentioned something about a generally settled spell at the end of August so perhaps the gfs 12z is on to something, at least I hope it is.

I certainly hope not! Anywho, just keep the charts coming?

[Frosty.]

just keep the charts coming?

I will

Interesting Ecm 12z this evening, becoming very warm and humid across southern areas during Friday and throughout the weekend with Sunday looking very warm and humid for a large swathe of the UK, hot in the s/se with mid 80's F, it looks to me like there could be some thunderstorms / heavy downpours breaking out and pushing north during the weekend. More warm weather at times next week too.

[Methuselah]

I will

Interesting Ecm 12z this evening, becoming very warm and humid across southern areas during Friday and throughout the weekend with Sunday looking very warm and humid for a large swathe of the UK, hot in the s/se with mid 80's F, it looks to me like there could be some thunderstorms / heavy downpours breaking out and pushing north during the weekend. More warm weather at times next week too.

I'll just about buy that...It's not far away from what the Beeb/MetO are suggesting.

[Nick F]

12z ECM deter sees quite a change from the 00z deter for the weekend, the 500mb trough to the west a lot more amplified on the 12z - which allows a shallow low to develop over France in response to the upper trough developing an increasingly -ve tilt before the surface low moves north across England and Wales on Sunday along a frontal boundary. Some very warm and humid air advecting north ahead of this boundary across the UK. But some heavy rain/storms along the boundary. No deep low on Monday like GFS either.

 

 

With this chopping and changing, 12z ECM deter actually quite similar to the 00z GFS op earlier today with regards to this weekend, it's difficult to put any detail beyond the end of the week. It seems the strong upper ridge over Scandinavia this week is causing some model wobbles as it tries to bring in an upper trough east from the Atlantic. It seems the models maybe too quick to push the Scandi block away, rather than disrupting the trough coming in from the west. The Atlantic trough wins out eventually next week though, but less convincingly now on ECM - with the block to the east and NE never really going away. 

 

I have a hunch that this may mean more in the way of warmth for parts of the UK towards the end of August, as the Atlantic upper trough fails to make too much inroads east past the meridian, thanks to that block.

 

Certainly the 12z EPS 500mb HGHTS/anomaly + CPC 8-14 day 500mb HGHTS point towards this:

 

Edited August 18, 2015 by Nick F

[knocker]

The ext ECM is not in agreement with NOAA and weakens the trough quite rapidly post T240 allowing the Azores to ridge weakly into the UK with the low pressure regime north over Iceland.

[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 WEDNESDAY AUG 19TH 2015

 

THE CURRENT GENERAL SITUATION Troughs of Low pressure will move NE across all areas over the next 24-48hrs in a mild and muggy SW flow. The troughs will linger across the far NE tomorrow..

 

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

 

MODELS-2 WEEK HEADLINE Remaining somewhat mixed with a lot of dry weather for all but with occasional rain too at times.

 

THE GFS JET STREAM FORECAST The GFS Jet Stream Forecast shows the flow moving SW to NE across Northern Britain in the coming few days. It hen backs South to North by the weekend and then cyclonic around Southern Britain late in the weekend before settling West to east across the UK for much of the rest of the period, gradually weakening somewhat.

 

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

 

GFS OPERATIONAL The GFS Operational Run today dare I ay it has an early Autumn complexion about it as for most of it's period it illustrates SW winds across the UK with changeable periods of weather ranging from some dry and bright conditions in the SE where it might still feel reasonably warm at times to unsettled and very windy conditions with gales and spells of rain, occasionally everywhere but most frequently over Northern and Western areas.

 

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

 

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

 

THE GFS CONTROL The GFS Control Run today though a little more kind for the South at times also has a look of early Autumn about it with eyes always looking to the West for the next spell of cloud, wind and rain but some good drier spells in the South and SE at times where humidity could be high at times and the longest drier spells look likely. The early Autumn look of things is then exacerbated late in the period by an ex tropical storm crossing the UK from the SW with heavy rain and severe gales shown for a time.

 

THE GFS CLUSTERS(14 Days) The GFS Clusters this morning show an emphasis towards Low pressure near Northern Britain with a Westerly flow across the UK with rain at times. Some members equally show a ridge over the South giving some lengthy dry spells here.

 

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 today shows Low pressure in control of the weather usually up to the NW but occasionally closer in with the trend for winds to increase and the influence of rain and showers to extend to all areas by the end of the weekend and start to next week and not just the North and West.

 

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

 

THE FAX CHARTS The Fax Charts this morning show a very complex series of troughs hung up over the UK for the coming three days with rain at times for many before a cold front staggers East at the weekend and introduces fresher conditions ahead of more disturbed weather poised in the Eastern Atlantic to begin next week.

 

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

 

GEM GEM today also shows changeable weather in SW winds with troughs decelerating as they move East across the UK in the coming few days. The SE may see the best of the weather still this side of next week before a spell of more changeable and sometimes wet and breezy weather for all looks likely. Towards the end of next week some improvements are shown again especially for the East and South but the Day 10 chart still manages to show a trough up across the UK squeezed between two higher pressure areas to the West and East.

 

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

 

NAVGEM NAVGEM looks quite unsettled this morning with Low pressure never far away to the West and NW throughout. Then early next week it too shows a vigorous little Low whistling NE across the South with heavy rain and strong winds for a time before the most unsettled conditions return to the North and West later next week but never leaves the South and East immune.

 

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

 

ECM ECM this morning shows a strong SW flow developing over the period with some quieter days in the South for a short period at the weekend. All areas will see some rain and showers in the coming days with the best of any dry and warmer weather in the SE. Then next week sees all areas become equally unsettled with periods of rain and strong winds alternating with showers and temperatures close to average right out to Day 10 when some improvements look imminent.

 

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

 

ECM 10 DAY MEAN The ECM 10 Day Mean Chart  from last evening shows Low pressure up to the NW with a SW flow likely over the UK with some rain at times for all but still chiefly towards Northern and Western parts with some warmth and dry weather at times in the SE.

 

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

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The models are coming together in showing a rather turbulent spell of weather next week with the potential for heavy rain and local gales at times.

 

31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The Verification Statistics of GFS, UKMO and ECM. This morning's verification statistics show ECM leading the way at 3 days with 95.9 pts followed by UKMO at 95.5 pts and GFS at 94.6pts. At 5 days ECM is stll king at 85.8 pts followed by UKMO at 85.0 and GFS at 83.1 pts. Then at 8 Days ECM still leads at 61.1 pts over GFS's 55.4 pts. Finally at Day 10 ECM leads GFS at 40.7 pts to 36.6 pts from GFS.

 

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 Not much cheer from the models this morning if it's fine and nationwide settled weather your after for the rest of the Summer as from this morning's output it looks very unlikely to happen. After a period between now and the weekend of SW winds and occasional rain for most the gradient of pressure involving Low pressure to the NW and High to the South and SE is going to steepen early next week as Low pressure takes a swipe at more Southern areas too as well as the North with attendant heavy rain and potential gales racing in off the Atlantic. After some relaxation of this feature last night a fair amount of output shows this vigorous Low this morning and while it's position and intensity remains uncertain at best it looks like all areas will see some very unsettled weather early next week with some heavy rain and fresh winds with temperatures closer to average. Most output then shows a mixture of evolutions ranging from a return to a NW/SE split in the weather again or a maintained sequence of Low pressure off the Atlantic crossing the North with fronts and further wind and rain continuing to plague the UK all the way to the end of August. I do feel though that taking specific details for weather in any one place beyond a weeks time is futile at the moment but the general pattern seems to be that with a Jet flow that looks like continuing to be well South of it's normal location over the Eastern Atlantic and over the UK for some considerable portion of the next two weeks the most likely scenario will be to maintain an Atlantic driven pattern with rain at times and temperatures near average and occasionally a bit above in the SE. 

 

Next update from 09:00 Thursday Aug 20th 2015

[johnholmes]

I think all thought of ridging playing a major part for most of the UK is stone dead looking at how the anomaly charts have evolved over the past few days. That covers the next 2 weeks or so. Glimpses of hope for the SE quarter but not for anywhere else it seems. What is not in the equation yet and will be sure to upset every applecart is the entry of any ex tropical storms. No model of any kind is able to deal with these from any time scale until maybe T+48 possibly T+72 for a general idea.

[ANYWEATHER]

Just a quick one as I'm holiday, and ouch comes to mind if you want a fine settled spell for the finale of summer. Unsettled just about sums it up for all ,with southeast England most favourable for tapping into any late summer heat. Time I feel to call last orders on proper summer weather. Of course that does not mean we won't some pleasant weather during Autumn

Edited August 19, 2015 by ANYWEATHER

[Winter Cold]

Saturday looks like a hot day for England. Some high temps showing which will hopefully lead to a fun evening when thunderstorms will spark off. Still looking good for Northern England and the Midlands:

 

  

 

 

Models look promising at this stage and netweather also mentioning the threat of storms in today's update so fingers crossed

[Geordiesnow]

I think one main theme in the current outputs is that despite it look like quite a wet outlook, it is still going to feel warm and muggy. I still would not be surprised if we do see a deeper low pressure system for Sunday as this has been hinted at and its one of those yet developed lows which the models could very much swap and change on albeit the odds does favour a more shallow low pressure system. 

[Polar Maritime]

Can we get back to discussing the 'Model Outputs' please in here, I thought i had logged on to a holiday/travel Forum.

 

Thanks, PM.

[knocker]

I don't know about Danny in the Atlantic but the super typhoons are sure churning up the Pacific. Downstream affects for the UK possible next week ?

 

Ryan Maue â€@RyanMaue 6m6 minutes ago

Two Super Typhoons can really build downstream ridges. GFS 12z has 600 dm contour touching Alaska next week (+3.8σ)

 

Ryan Maue â€@RyanMaue 23m23 minutes ago

Super Typhoon #Atsani recurves in North Pacific next week ... huge ridge & tropical upper-level air into Alaska.

Edited August 19, 2015 by knocker

[knocker]

Complicated analysis from the ECM beginning of next week.

 

Sunday 18z thundery low N. France with a band of rain associated with low north of Scotland lying along the west of the UK. Another low north west Spain.

 

By 12z Monday the French low has run north through the UK to be south west Scotland/ Negligible CAPE. Not that that means anything at this stage.

 

The GFS not running with this and brings a low in from the south west.

Edited August 19, 2015 by knocker

[Skullzrulerz]

​

 

Today's Wxmap's Showing Above Then Normal Temperature for the time of the year for most of the uk

[Man With Beard]

These troughs to the west do throw up quite bizarre changes run to run - get too close and its wind/rain/cool, a little further away and, like tonight's ECM, get blasts of southerly heat before a thundery breakdown. This weekend now looks good for the latter, the following week, who can say!

[knocker]

Interesting observation from NOAA this evening.

 

 FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOVE AVERAGE, 4 OUT OF 5, DUE  TO GOOD AGREEMENT AMONG THE VARIOUS MODEL GUIDANCE, OFFSET SLIGHTLY BY  UNCERTAINTY OVER THE NORTH PACIFIC AND ITS DOWNSTREAM IMPACTS, ALONG WITH  TROPICAL CYCLONE ACTIVITY OVER THE WESTERN ATLANTIC. 

 

Regarding the 8-14 it's possible edging towards the other anomalies with a weakening and positive inclination of the trough allowing an incursion of the Azores ridge. Yes well, that's the theory.

Edited August 20, 2015 by knocker

[summer blizzard]

 

 

 

Can't speak for the south east but Yorkshire northward is not pretty next week.

[knocker]

The analysis for the beginning of next week continues to be complicated and interesting, I've included  the Sunday and Monday fax charts which may help to shed some light.

 

At 00z Sunday this morning's GFS has a low moving up from France into southern England with a front stretching up through the UK with an approaching low out to the south west.

 

By 12z the UK low has nipped up to the Hebrides with the front edging east.

 

Twelve hours later, Monday 00 the front has reached the North Sea with the low to the south west now over Brest.

 

By 12z Monday this has morphed into a general slack area of low pressure over the whole of the UK.

 

So quick summary.

Looks like a band of rain crossing the UK on Sunday with the next batch arriving from the south west early Monday morning. Temperature wise the very warm air on Saturday (around 27C over England) is replaced by much cooler conditions as the front moves east. Perhaps some convective activity?

http://www.tropicaltidbits.com/

Edited August 20, 2015 by knocker

[Summer Sun]

Looking at Saturday and Sunday it could be a very warm and humid

 

 

If we have any rain it has the potential to be torrential at times with some thunderstorms

[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 THURSDAY AUG 20TH 2015

 

THE CURRENT GENERAL SITUATION. A large depression South of Iceland will dominate the Eastern Atlantic and the UK with a warm and moist SW flow across all areas.

 

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

 

MODELS-2 WEEK HEADLINE Remaining somewhat mixed with a lot of dry weather for all but with occasional rain too at times.

 

THE GFS JET STREAM FORECAST The GFS Jet Stream Forecast shows the flow moving SW to NE across Northern Britain in the coming few days. It then backs South to North by the weekend and then cyclonic around Southern Britain late in the weekend before settling West to East or SW to NE across the UK for much of the rest of the period.

 

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

 

GFS OPERATIONAL The GFS Operational Run today is once again a very changeable selection of charts indicating much as the Summer so far in that all areas will be at risk of some rain or showers at times with warm air flirting with the South and SE at times. A Low pressure complex developing near the UK later this weekend together with high humidity is shown to enhance the prospect of heavy rain for all before fresher Westerly winds return from next week.

 

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

 

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

 

THE GFS CONTROL The GFS Control Run today is largely similar in profile through Week 1 with an unsettled and occasionally wet prospect for a time late this weekend. Then Westerly winds are shown for next week with warm air again flirting with the SE at times, interrupted by further weakening troughs crossing over all areas later. At the end of the run pressure is shown to build across the UK bringing fine and settled weather to many areas to end the period.

 

THE GFS CLUSTERS(14 Days) The GFS Clusters this morning still show a bias towards Westerly winds over the UK most likely in two weeks with some members showing the South in particular under influence of High pressure. Confidence is quite low on any one evolution with a maximum of 35% indicated by a theme of slack pressure likely to be lying across the UK at that point.

 

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 today looks very unsettled as we look towards the latter half of the weekend and start to next week as Low pressure is shown to be centred over or to the West and North of the UK with rain and showers for all. It will be humid and warm in the SE at first but cooler air is shown to extend to many parts early next week.

 

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

 

THE FAX CHARTS The Fax Charts this morning show a very complex series of troughs hung up over the UK for the coming three days strengthening with time as very warm and humid air to the East of the troughs extend across the UK. The resuktant rain and drizzle of the next 24-48hr will become much more intense and thundery across the weekend before the fronts clear East by Monday with fresher but still unsettled air across the UK from then on into the new working week.

 

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

 

GEM GEM today shows cyclonic conditions across the UK throughout it's run this morning. There will be Low pressure over or eventually close to Northern Britain with thundery rain or showers gradually becoming replaced by cooler Atlantic winds and rain at times next week. Towards the end of the run improvements are shown to edge towards the South as High pressure slowly builds from there.

 

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

 

NAVGEM NAVGEM looks quite unsettled this morning too with Low pressure migrating slowly North across the UK late in the weekend and next week with thundery rain or showers in warm and humid air at the weekend turning into more traditional cooler Atlantic mix of rain and showers and sunny spells thereafter.

 

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

 

ECM ECM this morning looks unsettled too with rain at times, some very heavy and thundery over the weekend as Low pressure forming to the SW engages some very warm and humid air across the UK. Then through next week the Low complex moves North across the UK with the weather becoming generally unsettled, cooler and breezy with rain at times under less humid Westerly winds. Hints of a pressure rise from the South or West are hinted at right at the end of the run.

 

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

 

ECM 10 DAY MEAN The ECM 10 Day Mean Chart  from last evening maintains it's long lasting theme of Low pressure up to the NW and winds from a SW source across the UK with some rain or showers at times and warm air flirting with the South and East at times.

 

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

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The models stil show a lot of cyclonic weather across the UK next week with hints of some improvements in the second week of the period.

 

31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The Verification Statistics of GFS, UKMO and ECM. This morning's verification statistics show ECM leading the way at 3 days with 95.9 pts followed by UKMO at 95.5 pts and GFS at 94.7 pts. At 5 days ECM is stll king at 85.7 pts followed by UKMO at 85.3 and GFS at 83.1 pts. Then at 8 Days ECM still leads at 61.3 pts over GFS's 56.1 pts. Finally at Day 10 ECM leads GFS at 41.0 pts to 38.9 pts from GFS.

 

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 The spell of indifferent Summer weather where all areas see rain at times is going to continue for some considerable while yet and indeed from this morning's output it looks like some areas could get jolly wet before things start to improve a bit towards the end of the month. What we have currently is a moist and mild SW flow across the UK with some warm sunshine but coastal and hill fog and drizzly showers in the West. This continues for a day or so as pressure gently falls down to the SW. As a result of this winds back SE and very warm or hot air is wafted North into the UK at the weekend. With high humidity and instability aloft as pressure falls the ingredients are there for a period of rain and potential thunderstorms later in the weekend. Then next week we witness the slow progress of this Low pressure complex starting down to the SW to migrate towards the North of the UK opening the door for cooler, fresher Atlantic air from the West to flood across the UK. Low pressure remains the dominant feature up to the NW and North throughout next week though so further rain at times can be expected. Then as we move into Week 2 the jury appears to be out on specific detail but it does look like that a trend towards something drier, brighter and perhaps warmer is likely to return to at least the South of the UK at the end of the month. While this is a welcome sight with a bank holiday weekend looming it comes with the caveat that it is a long way out in weather forecasting terms and there is a lot of weather to get through first before we get there and plenty of time for the models to have a rethink on these events. The one thing that has receded this morning is the prospect of high winds as the rapidly deepening Low shown in the early part of next week has largely been removed now in preference of a still potent Low but with less pressure gradient around it. So all in all it's more of the same and I am still unable to report on the prospect of a sustained very warm spell again today though I will hang my hopes on the GFS Control Runs Week 2 suggestions here

 

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=336&mode=0&carte=0

 

as that would ensure something much nicer than anything else I can see in the models today.

 

Next update from 09:00 Friday Aug 21st 2015