minus10

Crazy spread...from +14 to - 13 850s !!

Rain All Night yes now in zonal wind reversal territory... ...expect to see some eractic model runs turning up...perhaps....

Mike Poole Thats just crazy...1 minute.....not expert in this but dont current model runs take a few hours?..this AI has the potential to revolutionalise the way modelled forecasting is produced...i should imagine far less computing power is needed although the AI still needs the input of traditional nwp runs..historical to inform its continual learning...but will there come a time when that is not required ?...

Incredible...wettest February since records started in 1856 here in the south according to the met.. ..also much warmer than average more broadly.. ...my own very untechnical rain guage recorded 120mm rain for February or 110mm upto 28th as this year is a leap...well over twice the average for this area..and another 22mm so far for March.. ..weidly woke up to a frost and mist this morning .... ...ground is so saturated though...as others have said desperately need period of dry weather...with some sun would be nice...as a gardener sodden ground makes usually enjoyable work very challenging... ..am i hopefull?..well a good start would be to see elimination of those rain spikes on the model runs... ....mmm...oh well there is another SSW on the way apparently... ...interestingly the latest ecm zonal wind chart keeps winds reversed from about 5th to 29th of this month...maybe enough time to promote some blocking that will enable drier weather to take hold...lets hope so, particularly for gardeners and growers..

Cheshire Freeze ..yes looking closer at the uk gfs0z it is a very wet picture for sw areas and pretty wet from north Wales down to London for next couple of weeks.. ..no wonder with this being continually being shown on gfs.. ...as i alluded to yesterday the position of the blocking high failing to prevent the atlantic trough from coming up around the base to south western areas.. ..those precip spikes keep appearing.. ..ec maybe bit drier but fair few rain spikes on the ens.. ...the drier spell many , including me are hoping for still not looking certain...

Well clear signal for the scandi high this morning...gfs,ecm and gem 0z ..even in the means.. ..problem is the previous hoped for drier picture not looking so secure now as with this pattern throughs are moving ese around the block with potential for more unsettled and cool weather.. ...rain spikes keep appearing later in the runs.. ...Pressure ens not indicative of longer periods of dry settled weather either..although significant uncertainty later on as you would expect... ...lets just hope it is not going to be miserable March...

Another trough dropped down and nowhere to go on the gfs 12z...

Dramatic difference in ecm0z and gfs6z day 10... ..whats going on??

Gfs keener to bring in the block from the ene...6z..day 10 ...although chilly in.any wind with perhaps frosty nights it should feel nice in the strengthening sun...and best of all..should be dry .. ...ecm still not so keen presently..

Main thing of concern down here in the south is the amount of rain...another 12mm here today...thoroughly miserable day...ground beyond saturated... ...so far this month here as recorded by my highly untechnical rain guage we have had 106mm...and eight of the last ten months well over 60mm rain has fallen.. ..hoping as per gfs 12z fi that this will allow some drying out.. ...however accumulated prec charts for day 10 gfs and ecm still show south and west catching lions share of the rain.. ...and a very wet France, particularly the south and northern tip of Iberia... ...some hints at higher pressure according to the ens.. ....although as seems to happen a lot lately with the gfs op it is an outlier later in the run. ..all a bit tenuous.... ...no longer interested in cold now...just want some dry or at least drier weather to be able to get out into the gardens....

Dennis looks like you have been left on your own mate ! ...good for you...keep flying the cold flag... ..edit see @Rain All Nightbeat me to it....

LRD wasnt suggesting you were mate..

LRD yes..take your point...i have probably been as guilty as others at taking pressure anoms too much at face value..need to use them in conjunction with other charts.... TIdbits has mslp contours and anomalies.. ..this illustrates your point nicely with the low to the south of Greenland..however would be good if there was a chart that showed height anomalies together with mslp...i am not aware of one but i may have missed it...

12z Gesf's 850s showing the lessening of the cold signal for the last week of Feb or so... ...although still represents a cooler than average period nothing exceptional...although op and control dipping later... ..the pressure shows the the op to be at lower end eg trough further south than the mean ... ...mean more in line with the way ecm has been going... ...not very encouraging for the last chance saloon for cold... ...the anoms still showing an atlantic ridge towards end of the month.. ...trough to the east and over north eastern Canada but what jumps out at you is the trough over the Aleuticians..bit of a monster and responsible for real cold over that area... ...the amount of above average temps over Europe and Eurasia is quite incredible by late February.. ...the Tropical Tidbits animation of temp anomalies over the hemisphere really shows the problem with getting cold in from a uk point of view.. 850s 2m ..the real cold is being shunted east over siberia and round to the Aleuticians and although the Atlantic ridge and trough over our part of the world is bringing sonewhat colder air it seems to be being watered down over time.. ..the main takeaway though is just the amount of warmth in the atmosphere over our side of the hemisphere..very hard i think to get any meaningfull cold with this situation..and time fast running out...

Difference between gfs0z and ecm at day 10 quite telling... ..looking at the jet you can clearly see the less amplified ecm.. ...you kind of just know dont you....

RJBingham was showing the gefs mean and comparing with the gfs op..

northwestsnow i thought you were hardcore!... gefs 12z still showing colder from soon after 22nd... ...however bit less cold from the ens although conversly colder op still... ..trough reaching down into spain with this run.. ...anoms also showing height lines with increased westerly component .. ...850 anoms little less cold.. ...so is this the start of the watering down of the colder signal (again) that the gefs has been modelling for days?...is it a wobble?...will the ops continue to be colder than the mean?...and of course the ssw ??? ...zonal winds should be in the process of weakening now however latest predicted reversal looks brief ...still all to play for i suppose...one last time...

daz_4 they are 2m temps....here's the uppers..

Gefs 12zstill continuing with the colder conditions for last week of February.. Slightly earlier the mean going below the long term average today..towards 22nd Feb.. ...its quite incredible though how different the 12z op is ..just continuing with that raging vortex to the north west.. ....and now as others have stated the ecm too.. ...although promise in the extended per the clusters... ...the long and winding garden path ??...

The gefs 12z still showing the colder pattern for last week of Feb.. this is what i am checking now to see if this stays in the modelling or gets put back/watered down etc..kind of last chance saloon really.. ...looking at the 850s 12z today compared to yesterday for when the mean drops though the long term mean to get an idea whether this is remaining or being pushed back... ...berween 22nd and 23rd still seems time slot for this...however we shall see...interesting ecm 12z though..

Does seem like endlessly chasing the pot of 'cold' at the end of the rainbow... Gefs 12z still wanting to cool down for the last few days of Feb..850 anoms ...homing in on Europe.. ...note how Scandi going into the freezer again..what a winter they have had...not a million miles away distance wise but the difference couldnt be more stark ... ...nw height rises and Scandi/ European trough still being signalled the cause of the modelled cooldown.. ...trough position not perhaps completely ideal but hey...would be an improvement on current synoptics... ..north westerly to northerly i would think... ...we really need to see this signal not pushed back any further and if possible moved forward a day or five...encouraging that the ec clusters that Mike analysed also show quite a lot of nw blocking / heights so ...come on...one last push .....to get that cold at the end of this very long rainbow..

Gfs 12z showing nice retrogression of heights from the east to the west/ north west in second half of run...with the scandi/ European trough digging down...

Well looking at the anomalies it seems there is still a reasonable signal for those height rises to the north west later in the month.. Gefs6z/eps 0z ...basic pattern similar on a broad scale with a split vortex?..more of a trough over scandi down to Europe on the Eps.. ...this height rise also shown on yesterdays cpc anoms.. ..what does this mean for the airmass temp though..looking at 850 temp anoms for gefs/eps for the same time.. ...seems that eps is more bullish with both the heat extending up into Siberia, heat over Greenland and Canada and also colder for the uk in general.. ..looking at the surface...2m temp anoms.. ...generally more heat around on the eps but also colder for most of the uk...interesting...as we know good broadscale synoptics often dont lead to colder air at 850 or indeed the surface but certainly on the anoms this colder signal for the uk is one we need to see gain traction..although overall it seems fairly tenuous when you consider the amount of heat also being shown.. ...one last point...the last 4 gefs runs.. ...ops aside...first sight they dont look that good however look closely and you can see the mean ever so slowly decreasing..back towards long term average and a bit below...also couple of ens hitting -14 850s in the latest...so if we are looking for trends then maybe this is a positive sign...fully understand that the situation is not good at present for cold with the many let downs...just trying to find evidence of more positive trends that could still deliver...

Looking at the gesf anoms 0z you could be forgiven for thinking that this is a good chart with blocking to the north west later this month.. ...however all is not what it seems...it seems...i think as others have stated the blocking signal is there but it is not in the right place for the uk..too far north to be effective for cold. The trough underneath allowing milder air up from the south... ..the gefs mean also shows this... More like an artic high ..while the op shows a meaty vortex again for around this time..only the op i know but talk about insult to injury!! ..in addition gfs op has been been at the higher end of the pack for a number of runs now with the mean also getting higher... ...this looks like a trend unfortunately... Even the eps are milder... ..the EPS anoms (only going out to t270 at present on Titbits) also showing that north west hight rise but again looks like it will not be effective for delivering cold to the uk if it goes the same way as gefs.. ..so although from a macro hemispheric perspective it may be going the way as dictated by the main drivers it seems as ever in the uk if the pieces dont fall right it wont make any difference...still can change of course and I really hope it does as would love to see a bit of proper cold before spring...but somehow i just feel it is slipping away... ...noticeable again this year the Daffs are up and out in some places...ground temps warmer than they should be...of course March colder snaps still likely and will cause problems for the flora... Original post: https://community.netweather.tv/topic/99814-model-output-discussion-22nd-jan-2024-onwards/?do=findComment&comment=5032526

Looking at the gesf anoms 0z you could be forgiven for thinking that this is a good chart with blocking to the north west later this month.. ...however all is not what it seems...it seems...i think as others have stated the blocking signal is there but it is not in the right place for the uk..too far north to be effective for cold. The trough underneath allowing milder air up from the south... ..the gefs mean also shows this... More like an artic high ..while the op shows a meaty vortex again for around this time..only the op i know but talk about insult to injury!! ..in addition gfs op has been been at the higher end of the pack for a number of runs now with the mean also getting higher... ...this looks like a trend unfortunately... Even the eps are milder... ..the EPS anoms (only going out to t270 at present on Titbits) also showing that north west hight rise but again looks like it will not be effective for delivering cold to the uk if it goes the same way as gefs.. ..so although from a macro hemispheric perspective it may be going the way as dictated by the main drivers it seems as ever in the uk if the pieces dont fall right it wont make any difference...still can change of course and I really hope it does as would love to see a bit of proper cold before spring...but somehow i just feel it is slipping away... ...noticeable again this year the Daffs are up and out in some places...ground temps warmer than they should be...of course March colder snaps still likely and will cause problems for the flora...