lorenzo

This link is an interesting read which looks at how ensembles are perturbed, lots of heavy going physics in parts, if you skim through it there are some great points of interest. It discusses in the main part the ECM approach to ensembles. http://www.elsevierscitech.com/emails/physics/climate/Ensemble_forecasting.pdf or try here, saw forecaster link this earlier this week in the model thread, http://www.ecmwf.int/products/forecasts/guide/user_guide.pdf

There are a few different spread charts around on meteociel some display difference in Dam or difference within ensembles. Blue Army is the best person to ask, he uses them a lot. My understanding is they are divergence from the mean. http://www.ecmwf.int/products/forecasts/d/charts/medium/eps/ensm/essential!Temperature%20at%20850hPa!Europe!192!pop!od!enfo!plot_ensm_essential!2012011212!!/ The NAEFS aside from being the best verifying ensemble suite, is interesting for the selections on offer - http://www.meteociel.fr/modeles/naefs_cartes.php?ech=6&code=6&mode=0&map=&runpara= You have Mode - minimum 10% , mediane and maximum 90%, which when selected present the charts in standard z500 style.

Yeah saw Ian F comments, good to read as this answers a lot of discussion in the model discussion about TV discussion! Also interesting to read of the projected Easterly influence, hope he drops another post in later on how they view the UKMO run, will heighten anticipation if less modified than previous evenings. Would be great if more of their stuff was in public domain, especially now the tight airsed ECMWF have removed the free access to the ensembles and the sample page. Grrr.

Try these BUS, it's a GIF you are wanting to make. http://picasion.com/ http://imgflip.com/gifgenerator LS were you looking for NAE earlier ? http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=ukuk&MODELL=nae&MODELLTYP=1&BASE=200912201800&VAR=tmin&HH=24&ARCHIV=0&ZOOM=0&PANEL=0&WMO= Also whilst I am at the links, found this random link for the Fax Charts http://weather.noaa.gov/fax/otherfax.shtml

Put these in the Regional thread, best to share here too. ECM Ens & Spread Interesting reading Matt on Twitter mentioning the 84 hrs Fax chart and the problematic potential development of a low currently in situe SW of Iceland. Will be something to watch in the next 12-24 hrs. From NMM on NetWx, some damn fine looking cold air. Progression of the 850hpa temps, I like this view as you see exactly what is going on with the WAA over Greenland, earlier in the week this was more inclined to Baffin Bay versus over the peninsula itself. After this a close watch to see where the high goes, GWO giving credence to the Scandi Block and then backing West again, am hoping it cycles as projected and we get something like this..

Couple of charts to save on hazmat suits.. ! 850hpa Temps and Wind Vectors, the Atlantic view details the Warm Air Advection over Greenland and the colder air inbound for the start of the week. Fax charts from this morning, show the 528 line comfortably travelling down the country with a couple of troughs in the flow. 510 dam air not too far behind, but from the chart below you can see the warmer upper air drifting east as the high elongates. End position from the mean shows the relocation of the blocking to Scandi. However, looking at the spread which for want of a better description is how sure the models are on what's going to happen next, or , Shannon Entropy, for a more technical meto. phrase, we can see that the positioning of the High Latitude blocking is far from certain. Warmer colours - less confidence. FI then at 120 hrs / Day 5. Monday evening and we will be on the radar and looking at lamp posts, this from NMM on NetWeather Extra. NAE will be worth a look as it rolls out over the weekend, hopefully a few busted snow shields to start the season...

If you add the images side by side rather than heading vertically down the page, they open and when open the arrow key appears to allow you to move onto the next image.

Just visited model thread...hard work for the mods in there tonight...! Right pub run...bring the madness..

Had a good look at the strat charts this morning, Interesting vorticity charts within the next 24 hours at the Tropopause level and as a result on the 100hpa strat heights chart. Interesting due to the repeat of the trend in the atmosphere which continues for earlier Autumn to deliver troughing deep into the heart of the continent, this energy also diluting the vortex somewhat and leading to clear elongation by day 10. Diagram gives example of the heights of the PV surfaces. EP Flux is interesting also the peak influence as a result of that huge ridge across the other side of the globe, with peaks on the 8th and the 12th. Chart from the 8th has the vectors smashing in all directions which to me is a sign of some of the energy impacting the vortex. The hovmoller plot pretty clear for November. Some activity developing again at day 10 on wave 2 plots. The impact of the displacements caused by that mean Aleutian high, combined with the Atlantic ridging forecast making things interesting as November continues especially where the core of the Vortex is destined again for Siberia, at 50hpa the Strat troughing and relocation. With respect to the AO forecasts and this rampaging negative plot from GEFS, if OPI mean AO figure turns out to be accurate and verified for DJFM as a whole, with this plot verifying for November, what kind of ominous AO figure would we expect for the rest of Winter?

LOL ! Wonder what this actually ended up at !!

GFS Pub Run & Control Run - delivering epic craziness.

GFS pub run & Control run = more madness.. That's an early 80s January winter chart..!!

http://www.weathercharts.org/ukmomslp.htm#t120 I like that link because they are time stamped and it saves my brain working out if am looking at the latest one or last nights !

Check where the 528dam line is on the one.. Lovely.

Welcome back - LOL nearly -40 500hpa temps on that Control run earlier..

Wow, bit of an epic 24 hours of model runs, looking at some of these charts is eye watering in the midst of a proper industrial 2 day hangover. Too old for mid week partying til 4am ! Insane Control Run. A real box of frogs. This is a pleasure to see at just 144hrs out. -9.7 850hpa temps on tonight 12z. Some crazy, crazy model watching the propensity of High Pressure to develop across the NH in that control run is one of the maddest things I think have seen.. Some great, great posts today. Superb analysis, Debbie Harry, Kelly LeBrock - ooft ! magic Video Ben and a whole bunch of wild charts in the offing. Cannae beat model watching in Winter. Though we might get something exciting, certainly did not expect a 2010 revisited.. Very interesting from here creeping into Fax range.

Atlantic tripole correlates with negative NAO and improved blocking. On phone so can't chart to illustrate. Google tripole ssta nao loads of papers come up

Nice and clear again this morning. Couple of 'other' charts that don't normally put in an appearance among the regular ones, both highlighting the trend for blocked Atlantic and falling 850hpa temps. Meteogram for Aberdeen NAEFS - best verifying of all the ensemble runs, just marginally ahead of GEFS, this at 180 which means it is staying with the trend. Way out in GFS FI there are some mad charts, well there always are, but in particular the modelling of the vortex and it's drop into Europe is insane, worth keeping an eye on.

More on verification...I caught a video over the weekend where Big Joe B advised that the CFS was outperforming the GFS at some points already this season. Not inspiring confidence on the Winter ahead from the GFS. Found the Ensembles within that page, NAEFS showing exactly why it is closely monitored. Next one is interesting as it compares within the ECM op with the control run. GFS ---> NCEP GFS forecasts from T00Z ECM ---> ECMWFf orecasts from T12Z CTL ---> NCEP ensemble control forecasts from T00Z ctl ---> ECMWF ensemble control forecasts from T12Z If anyone wants to have a look through try http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/ensm/ and http://www.emc.ncep.noaa.gov/GEFS/verif.php

This page is also excellent within the Roundy pages, bit of a technical challenge to read ! Directory of MJO HovMoller plots - http://www.atmos.albany.edu/facstaff/roundy/waves/hovsdetmjo/ Current equatorial Plot - http://www.atmos.albany.edu/facstaff/roundy/waves/hovsdetmjo/0_7.5N/2013.png

The zonal wind profile on Berlin site shows the GWO impact well. Had to double check the year at day 5 or so it looks like an easterly QBO. That wave 2 plot is a great watch upwelling then completely across the grid. Heights

Managed to get along to last months meeting, can't make this one unfortunately, work calls, off to Manchester to attend an awards gig, managed to somehow convince someone that I actually work when at the office. Cannae turn down a free bar and free evening meal, plus an overnight in a hotel, with no hungry baby waking you up at silly o'clock ! Hopefully you all get to meet up, great idea, if it doesn't happen this time, we should arrange a date for all fellow Kilters to meet up and have a few ales and a blether.

CFS or GFS !! 12z going off on one... All day pub session from the GFS today, rather than waiting til the evening.

Just to save Buried any confusion, am not Lorenzo either.. Totally agree with LSorenzos post above, flipping from the Winter Side of November back to the Autumnal. Rain Today already loaded over Ireland..

Much the same here Cheggers, took a wander out to the local shop around 8pm last night and nearly fell on my airse a few times. Not got a weather station of any kind, but it was cold enough to freeze the wheely bin lid shut, which I guess is -2 / -3 overnight. Still looks frosty out there, Atlantic action inbound. http://meteocentre.com/sat/get_sat.php?map=_vis&anim=1&area=uk〈=en From the Hi Res Satellite, snow cover extent on the mountains looking amazing. Here's another site to play around with Meteogram comparisons. http://meteocentre.com/models/get_mgram.php?stn=Aberdeen&mod=compar&run=12&var=std〈=en&map=UK