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Model Output Discussion; into 2015


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I agree with the pessimist on here and I live at a modest altitude up north!

Cool zonality rarely delivers even up here as snow tends to be restricted to areas from the Southern Uplands northwards, cold zonality like January 1984 is as rare as rocking horse droppings.

I think this pattern of cool wind and rain will be with us a long while as indicated on the GEFS, the pattern could become more amplified later in January but at the moment that is just hope casting.

The only positive I can find is that a Bartlett pattern is unlikely so we should get some nice sunny spells between depressions and of course it's great for the Scottish ski industry who,s demise was clearly overdone several years ago.

Andy

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12z clusters are offering glimpses of a different story after mid-month with markedly more meridional pattern(s), but of course it's just not worth detailing all that stuff showing out post-15 Jan unt

Some very poor quality posts have been creeping into the discussion which really don't add anything to the thread apart from raising the ire of many who view this thread....Even a simpleton (in meteor

Nice tease from the ECM, no surprise looking at the strat charts, shame it can't happen though because apparently cold is not possible before Mid Jan!?!   Rule nothing out folks, as I posted yeste

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Does everyone remember all that pre Christmas drama with the models well the verification stats for the 12hrs outputs show just how dismal their performance was:

 

They all fell off a cliff, the UKMO came out best, the ECM/GFS were woeful but the wooden spoon goes to the GEM!

 

attachicon.gifcor_day6_HGT_P500_G2NHX.png

That's interesting Nick. I wonder what caused such a drop!

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That's interesting Nick. I wonder what caused such a drop!

If I remember it was the drama over the low to the sw and the shortwave ejection ne'wards. The ECM also had that western negative NAO for a while but that was further out.

 

As soon as the models are given anything difficult to deal with they often make a hash of it! We should bear this in mind with that Arctic high possibility and theres also now the drama with that shortwave to the north and the upstream Canadian low in terms of track and depth.

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Not at all I think, the op wanted to give a period of west-based -NAO; none of the models picked the eventual outcome until T120 - ensemble means or op runs.

 

Thanks. I'm sure it was the first to spot the low SE of Greenland though.

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If I remember it was the drama over the low to the sw and the shortwave ejection ne'wards. The ECM also had that western negative NAO for a while but that was further out.

 

As soon as the models are given anything difficult to deal with they often make a hash of it! We should bear this in mind with that Arctic high possibility and theres also now the drama with that shortwave to the north and the upstream Canadian low in terms of track and depth.

This is the trouble with getting true cold to our shores - too many variables! I certainly won't be counting on that arctic high to save us, that's one thing I do know. It just lols about on the other side of the pole and must think this side of the pole smells too much!
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There is a lot to like about the Gfs 06z if you like cold weather, there are several reloads of polar / arctic air throughout the run but more especially during low res as we tap into cold air more frequently, so, lots of snow showers and sharp frosts during early January if this run comes off. Technically mild days are few and far between, next Thursday would be the first but then it turns colder from the NW.

post-4783-0-93966600-1419772491_thumb.pn

post-4783-0-15680200-1419772579_thumb.pn

post-4783-0-22544500-1419772705_thumb.pn

post-4783-0-26362400-1419772730_thumb.pn

post-4783-0-29630000-1419772770_thumb.pn

Edited by Frosty.
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This is the trouble with getting true cold to our shores - too many variables! I certainly won't be counting on that arctic high to save us, that's one thing I do know. It just lols about on the other side of the pole and must think this side of the pole smells too much!

Are headache is the Azores heights coupled with a resilient vortex and in terms of solar activity it most certainly seems to feed Azores domination I don't know exactly why but something that I've been very interested in since the start of cycle24.

Although it is worth taking note there is no Bartlett high and awhile back some models did seem to show this setup.

Although since that idea has been dropped!.

so really in this aspect no uncle Barry does favour the North getting something!.

But by far it's no where near ideal.

The ukmo is the best model and over the next few days I will be keeping a keen eye on the ecm up to 144 and the ukmo

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There is a lot to like about the Gfs 06z if you like cold weather, there are several reloads of polar / arctic air throughout the run but more especially during low res as we tap into cold air more frequently, so, lots of snow showers and sharp frosts during early January if this run comes off. Technically mild days are few and far between, next Thursday would be the first but then it turns colder from the NW.

It is great if you like a windy, rainy set up.

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This is the trouble with getting true cold to our shores - too many variables! I certainly won't be counting on that arctic high to save us, that's one thing I do know. It just lols about on the other side of the pole and must think this side of the pole smells too much!

Yes but it can help force the jet further south, at this point it's a leap of faith to see some cross polar flow developing but I'd rather see the Arctic high than some PV blob in that region.

 

I should add regarding the Canadian Low if updated comments from NCEP regarding that are correct then the GFS P 06hrs run will not verify, you'll see from their view in the Michigan state forecasts that this bears no resemblance to that output.

 

...WITH THE 500MB LOW IN THE SW PUSHING ACROSS THE S PLAINS

AND NUDGING A SFC LOW UP THE MS VALLEY...TO AROUND CENTRAL/S LOWER

MI BY 18Z SATURDAY...THEN RAPIDLY DEEPENING ACROSS S ONTARIO AND

QUEBEC SATURDAY NIGHT.

 

It's hard to tell with the UKMO as it has the shortwave but weakish at that point, but one things for certain if you're a coldie you want  to see that deepening upstream low.

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Hi guys/gals-I don't often post in the model thread as I really do not have the knowledge to 'suss' out the charts! All I can say (& sorry this is a bit IMBY )is that where I live-165m asl near Huddersfield it hardly got above freezing yesterday & is 1 degree today-lovely picture postcard scenery here in the pennines. There was as far as I can gather MORE snow in a more extensive area & the snow was not just high ground. So...with all the science & models in the world....mother nature can catch us out & give more snow than forecast. I seem to remember a few days ago the extent of snow was not forecast to this degree. Anyway-I'm rambling-I still 'feel' this winter will deliver more extensive snow. Mods-please delete if you feel this post is not appropriate..........

 

P.S. Frosty-did you get snow in Wakefield?

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The long-wave pattern is pretty bog standard zonal - yes there are some polar maritime incursions and some model runs suggest the jet digging south but all in all pretty normal January faire.

 

The NAO ensembles suggest a pretty positive NAO going forward:

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/nao.sprd2.gif

 

This can be clearly seen in the 10 day means (caveats accepted)...

 

gensnh-21-1-240.png?6

 

EDH1-240.GIF

 

 

Yes, this is an improvement on last year but we were really expecting things to be worse?  December CET is currently a very mild 5.9C and I expect January CET (first 10 days) to be pretty average or even slightly above.

 

I'm just reporting what the models are showing - there are changes afoot viz. the strat and I'm not sure if and when these will be reflected in the NWP.

Edited by mulzy
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.

 

I'm just reporting what the models are showing - there are changes afoot viz. the strat and I'm not sure if and when these will be reflected in the NWP.

Exactly my friend. There's lots of interest going on over in the strat thread and surely the models are not picking up on this yet. If a strat warming event takes place, which is more than possible in the near future, then the models are sure to get more interesting sooner than we think.

So in the short term things are looking a bit iffy, but by as soon as late next week we could be seeing a completely different picture.

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Looks like a very unsettled pattern taking hold as we head into January, wet & windy even stormy at times. It'll be on the cool/cold side mainly with PM incursions which would produce snow for northern hills and perhaps to some lower levels at times in what look like marginal situations with a mainly Atlantic flow. Enjoy the first half of this week which will produce some crisp clear & frosty winter weather, if that's what floats your boat! 

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The trend is your friend. I like the UKMO at 00z because it built further on the 12z with better height gains over GL and more favorable orientation of that Artic high. I think something good is going to show up within the 168 time frame very soon maybe even today. The ECM is even better than the UKMO at 144hrs. We can work with this. It's all about the trend toward more amplification + split PV - also note the gradual weakening of the vortex over Canada in the last 4 runs has been very noticeable.

 

Recm1441.gif

Edited by The Eagle
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Hi all!

 

Nice models after the 5th of jan for cold but I am very new with this charts so I would like to ask...

 

what model predicted or got closer (long range or mid range) the cold event that we had on boxing day??? I would like to see if it can do the same over the next 2nd half of january.

which would you guys say is the best models to watch out? I always look GFS and EcM together with UKMO but Id like to know your opinion for these cold events, models tend to exagerate or under-rate certain patterns and I dont think there is just one that does the good work but would be good to know which is good for what.. (not sure if this is off toping... if it is, sorry! :) )

 

 

I know that its difficultbecause they are in FI but a week before this recent cold event we were 14 degrees in warrington... anything can happen, no?

 

thanks to all!!! I love the thread!

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Yes but it can help force the jet further south, at this point it's a leap of faith to see some cross polar flow developing but I'd rather see the Arctic high than some PV blob in that region.

 

I should add regarding the Canadian Low if updated comments from NCEP regarding that are correct then the GFS P 06hrs run will not verify, you'll see from their view in the Michigan state forecasts that this bears no resemblance to that output.

 

...WITH THE 500MB LOW IN THE SW PUSHING ACROSS THE S PLAINS

AND NUDGING A SFC LOW UP THE MS VALLEY...TO AROUND CENTRAL/S LOWER

MI BY 18Z SATURDAY...THEN RAPIDLY DEEPENING ACROSS S ONTARIO AND

QUEBEC SATURDAY NIGHT.

 

It's hard to tell with the UKMO as it has the shortwave but weakish at that point, but one things for certain if you're a coldie you want  to see that deepening upstream low.

All eyes on the eastern states at 144hrs on tonight's 12z runs. Nail biting stuff yet again but we love it lol.
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I'm taking all the NWP outputs with a pinch of salt at the moment. I think we are almost guaranteed a Sudden Stratospheric Warming and with Zonal winds at 1HPa switching from over 150mph last week to a standstill nxt week. This will play havoc with the models. I expect to see lots of choping and changing as to where a block will form.

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The trend is your friend. I like the UKMO at 00z because it built further on the 12z with better height gains over GL and more favorable orientation of that Artic high. I think something good is going to show up within the 168 time frame very soon maybe even today. The ECM is even better than the UKMO at 144hrs. We can work with this. It's all about the trend toward more amplification + split PV - also note the gradual weakening of the vortex over Canada in the last 4 runs has been very noticeable.

 

Recm1441.gif

 

That is a surface high with little WAA and the Atlantic flow just pushes it east. Later at D8 the ECM op tries again but at that range the mean is the best bet:

 

post-14819-0-94498500-1419777588_thumb.gpost-14819-0-30154400-1419777589_thumb.g

 

The op has very little support from it's members, and although some may say the hi-res is leading it's members; if that was the case this winter would have been a snowfest of GH, SH, etc. None of the ECM D8-10 blocking signals have verified this winter and there have been plenty of them. Of course this may be the run that proves the rule but IMO that is v. unlikely.

Edited by i'm dreaming of...
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Models past day 5 will continue to chop and change, I think until we know what's happening with the strat then we will continue to see big differences in the model outputs.

Our next cold spell could come out of nowhere, as stated above all eyes are on the eastern side of the states to see if we can lose the vortex over Canada and move heights into Greenland. Hopefully we get a SSW in the next 10 days which can only aid in our hunt for our next cold snap.

The good thing though is the vortex is nowhere near as strong as last year so we can forget about a repeat of last winters rubbish, even without Northern blocking the trend for Northern incursions will still keep our winter interesting. Game on

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I'm taking all the NWP outputs with a pinch of salt at the moment. I think we are almost guaranteed a Sudden Stratospheric Warming and with Zonal winds at 1HPa switching from over 150mph last week to a standstill nxt week. This will play havoc with the models. I expect to see lots of choping and changing as to where a block will form.

 

I am not confident of an SSW from the current warming, though still a chance. So more likely we will have to wait till after mid-Jan. That may have a quick trop response but if we have to wait 1-2 weeks then the last week of Jan may be favourite IMO. So I doubt we will see anything in the GEFS for 1-2 weeks yet? I am not sure if the current Alaskan Ridge/Polar High (potential) is a trop response to the current forecast warming but suspect it is as the November Pacific ridge was at least partly accredited to the earlier warming.

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It could be a stormy start to the new year as a vigorous depression heads towards nw Scotland, the same feature is then responsible for drawing colder air SE during Friday and Saturday with increasingly wintry showers, especially in the north. So although it will turn milder late in the week, it soon turns colder again with frosts returning.

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None of the ECM D8-10 blocking signals have verified this winter and there have been plenty of them. Of course this may be the run that proves the rule but IMO that is v. unlikely.

 

Not quite true. This was the forecast 8 days ago for today:

 

get_legacy_plot-web248-20141228151639-15

 

Here we are today:

 

ECM1-0.GIF?28-12

 

It's pretty close. At T+144 and above all models struggle but to state that none of the ECM high pressure forecasts at 8-10 days have verified is incorrect. In many years of model watching I have seen nothing to suggest that GFS, GEM or JMA are any better at accurately predicting blocks and their position. 

Edited by Catacol_Highlander
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Not quite true. This was the forecast 8 days ago for today:

 

get_legacy_plot-web248-20141228151639-15

 

Here we are today:

 

ECM1-0.GIF?28-12

 

It's pretty close. At T+144 and above all models struggle but to state that none of the ECM high pressure forecasts at 8-10 days have verified is incorrect. In many years of model watching I have seen nothing to suggest that GFS, GEM or JMA are any better at accurately predicting blocks and their position. 

 

Isn't that a toppler Atlantic Ridge. Not sure I would classify that as a block? But I maybe wrong. The day before it was showing:

 

post-14819-0-78636300-1419780581_thumb.g

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