Jump to content
Sign in to follow this  
Paul

Model output discussion - 20th Feb onwards

Recommended Posts

2 minutes ago, IDO said:

And of course it's one run; it's the 06z, so worthless after D7; has no support from its mean and an outlier in FI:

gensnh-21-1-384.thumb.png.d94fa155f98a18graphe6_1000_306_141___Londres.thumb.gifgraphe4_1000_306_141___Londres.thumb.gif:

 

 

Nonsense. The 06z isn't 'useless.' I don't know why this old chestnut keeps getting brought up. A mean chart for two weeks away on the other hand is truly useless.

Share this post


Link to post
Share on other sites
17 minutes ago, solarcycle said:

Nonsense. The 06z isn't 'useless.' I don't know why this old chestnut keeps getting brought up. A mean chart for two weeks away on the other hand is truly useless.

I disagree I think the 10-15 anomalies, used correctly, and in conjunction with det. outputs, are very useful tool in establishing the upper air pattern which obviously drives surface developments.

Regarding the MJO to my untutored eye the ECM seasonal models do not look particularly amplified.

E.thumb.jpg.6de13163d1d22dacb2fc4fe19f7356d1a85cf0160_E1.thumb.jpg.0f392e3132348

 

Edited by knocker

Share this post


Link to post
Share on other sites
10 minutes ago, solarcycle said:

Nonsense. The 06z isn't 'useless.' I don't know why this old chestnut keeps getting brought up. A mean chart for two weeks away on the other hand is truly useless.

Hi

Please read this as it will explain why you are mistaken. The 06z has less data put in and that is essential as by the time D7 comes, that loss of data increases the error with time. This is a scientific study so may put this debate to rest. The 06z is poor compared to the 0z and 12z and when there is entropy then this magnifies its "uselessness":

https://ams.confex.com/ams/27WAF23NWP/webprogram/Handout/Paper273676/GFS4cycle_2015_NWP_Chicago_15A.pdf

 

Share this post


Link to post
Share on other sites

the 06 always seems too progressive a run when compared to other gfs runs,see it every time in the winter

 

Share this post


Link to post
Share on other sites
54 minutes ago, SLEETY said:

yes what is the reason behind the air not getting that cold,the unusual warm in the Artic this Winter??

 

Global warming has to be a factor.  Certainly the lack of ice north of Norway too.

Share this post


Link to post
Share on other sites
1 hour ago, SLEETY said:

yes what is the reason behind the air not getting that cold,the unusual warm in the Artic this Winter??

 

 

13 minutes ago, mountain shadow said:

Global warming has to be a factor.  Certainly the lack of ice north of Norway too.

The super el nino and of course climate/global warming. It saddens me to say it, but a warming Arctic is the future and something that every winter forecast from now on will have to factor!

By the way, I disagree with people who say that it is late in the season for those synoptics to deliver. February and March are normally very good months for snow but what we know as normal is currently changing.

Edited by karyo

Share this post


Link to post
Share on other sites

no interest for wednesday 84 hours away then?

gfs-2-84.png?12

gfs-2-90.png?12

gfs-2-96.png?12

or friday next week?

gfs-2-144.png?12

Share this post


Link to post
Share on other sites
2 minutes ago, andymusic said:

no interest for wednesday 84 hours away then?

 

gfs-2-96.png?12

...but if you look at the 0c Isotherm then that snow will only fall at over 600 meters on Wednesday and 300m on Friday (at least):

Wednesday: 96-526UK.thumb.gif.855cc5ccb6a41bc7556ee  Friday: 144-526UK.thumb.gif.83c93ca6ffcd5c9f4b96

Not much use for most of us in that zone.

Its best when looking at those charts to align them with other metrics, otherwise they can be misleading.

Share this post


Link to post
Share on other sites
32 minutes ago, IDO said:

...but if you look at the 0c Isotherm then that snow will only fall at over 600 meters on Wednesday and 300m on Friday (at least):

Its best when looking at those charts to align them with other metrics, otherwise they can be misleading.

I don't think you need 0C for snow, that just shows the freezing level...conditions would have to be exceptional in March to get an 'ice day' anyway. As discussed before, it's quite possible to get snow when temperatures are well above freezing, as long as other conditions are perfect. 

Nevertheless, I'm quite sure the GFS is overcooking the snow risk. 

Edited by PerfectStorm

Share this post


Link to post
Share on other sites

All fairly academic at this range,but conditions on Wednesday and Friday morning  are favourable for snow falling down to quite low levels,although how much would actually settle is another matter.

 

Both days have 850's between -4 and -7 with sub-zero dew-points as well as low thicknesses.

 

Wed..90-7UK.thumb.GIF.6f2d3471706763113f7e00290-101UK.thumb.GIF.1747bb54f436af4769e1e

 

Fri..138-7UK.thumb.GIF.097c140da4352483f002e7138-101UK.thumb.GIF.01d9611f501f991e4559

Share this post


Link to post
Share on other sites

Worth keeping an eye on

 

16030406_2_2712.gif

Rtavn1383.gif

Given the time of day a covering could well be possible

Moves further South later

16030412_2_2712.gif

 

 

Edited by Banbury

Share this post


Link to post
Share on other sites

ECH1-168.GIF?27-0

ECM continues the chilly unsettled theme, wintry for North one would think

Share this post


Link to post
Share on other sites
1 minute ago, Banbury said:

ECH1-168.GIF?27-0

ECM continues the chilly unsettled theme, wintry for North one would think

Decent ridging again but again underwhelming cold pooling to our north.

A look at the 850 anomalies modeled up there tells the story

ECH100-144.GIF?27-0

no doubt some snowfall for Scotland,especially the higher ground,though.

Apart from the general background of a strong pv through the Winter I do wonder whether the frequent warm air ridging into northern Russia has continually undermined a stable cold pool being able to establish to our north. east.

 

Share this post


Link to post
Share on other sites
12 minutes ago, Banbury said:

ECH1-168.GIF?27-0

ECM continues the chilly unsettled theme, wintry for North one would think

Can't see much away from the hills / mountains to be quite honest the 850's just aren't cold enough

ECM0-168.GIF?27-0

Share this post


Link to post
Share on other sites

I'm beginning to wonder whether these on the face of it good synoptics are just the final insult. All winter spent chasing some decent synoptics and as soon as some appear any decent cold to tap into is nowhere to be seen.

You can see the problem on the ECM even when a chunk of colder air appears near Iceland theres no decent ridge to help pull that in to the UK.

Without a strong block its hard to see where any deep cold is going to come from.

Share this post


Link to post
Share on other sites
1 hour ago, Summer Sun said:

Can't see much away from the hills / mountains to be quite honest the 850's just aren't cold enough

ECM0-168.GIF?27-0

At 1300 hours too true , but through the night time and early hours snow could be a possibilty

Share this post


Link to post
Share on other sites

Every cold spell modeled this year shows major snow event then to be watered down closer to the event with warm sectors popping up everywhere it just not happening this year time to move on and look forward to spring we can do this next winter hopefully with more success as this year is a bust for the majority of us.. .

Share this post


Link to post
Share on other sites

The final insult for coldies right now after such a poor almost non existent winter would be a prolonged spell of very mild south or south westerly winds but I'm just not seeing any sign of that. The Ecm 12z for example shows most of our weather for the next 10 days or more coming from the north west more than anywhere else with the jet generally aligned nw / se..so, mild weather in very short supply apart from briefly around next tues / wed and mostly rather colder and continuing unsettled thereafter, cold enough at times for a wintry mix, even some snow at times but probably the highest chance of snow further north and with elevation but I'm not seeing anything spring like. 

ecmt850.096.png

ecmt850.144.png

ecmt850.168.png

ecmt850.192.png

ecmt850.216.png

ecmt850.240.png

Share this post


Link to post
Share on other sites
13 minutes ago, Banbury said:

Agreed Frosty, nothing Spring like at all

Really, as a coldie I'm quite encouraged by the latest models as there is generally a signal for below average temperatures indicated and rather cold at times. I also understand that we could be looking at winds predominantly from north of west, perhaps even a direct northerly from the arctic at times during march..unless I am mistaken.

I'm not ready to let go of wintry potential in march or even April for that matter having been so short changed from the last 3 months!:)

Share this post


Link to post
Share on other sites

Today we were under these values in the south of the U.K. And we're seeing temperatures at the surface of 7-8c. 

Any other year, if some said to me with 850's and DP that low with an easterly feed you'll get to 7-9c, I would laugh.

still time for a surprise, but without any real embedded cold to tap into, it's not looking good. Very different to 2013.

 

image.gif

image.gif

Share this post


Link to post
Share on other sites
3 minutes ago, karlos1983 said:

Today we were under these values in the south of the U.K. And we're seeing temperatures at the surface of 7-8c. 

Any other year, if some said to me with 850's and DP that low with an easterly feed you'll get to 7-9c, I would laugh.

still time for a surprise, but without any real embedded cold to tap into, it's not looking good. Very different to 2013.

 

image.gif

image.gif

time of year surely? Dec wouldn't be 8C, would be 0-1

Share this post


Link to post
Share on other sites

Evening all :)

A few reflections on this evening's 12Z output (even as the 18Z GFS OP starts rolling out).

I first saw in the GFS Parallel a couple of days ago a trend toward MLB rather than HLB and I still see that for early March. I had hoped next weekend's LP dive into Europe might be sufficient amplification to see the long sought-after link between the Greenland and Azores HP and the much-cherished mid-Atlantic block and to be fair GFS still offers retrogression in FI but more immediately the Azores HP moves north but stops and the jet is too strong for the ridging to occur.

Again, to be fair, GEM tonight keeps us in the cold though the synoptic evolution looks doubtful to my eyes while ECM is also predominantly cold into next weekend.  The GFS Members are still strongly in the cold camp and, again to be fair, HLB via a Scandi HP is well represented.

The problem, as has been well documented, is the lack of a significant cold pool in the vicinity. Oddly enough, I'm less concerned about that if we can get the synoptic pattern right as N or NE airflows in March can get very cold very quickly (better than a pure E'ly).

I feel we've nudged half a step back from a strongly below-average March (and no one's talking about 2013) to simply a below-average but there's plenty of cards still on the table and we've certainly got (after a mild snap early in the week) a likely return to some unpleasant if not unusual conditions from midweek onward (and some quite strong winds down the east coast in particular). I presume no one is concerned about tidal flooding issues at this time.

 

 

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.
Sign in to follow this  

×
×
  • Create New...