Model Output Discussion - 14th Jan 12z Onwards

[Polar Maritime]

A cold N/N/W Pm flow to end the run, Turning North, But with so much uncertainty mid-term I would't take much notice, If at all..

 

Edited January 15, 2015 by Polar Maritime

[Captain Shortwave]

Question is PM,is Teits looking at same output because that screams heavy snow showers pushing well inland.

It's a job for nearer the time to be honest when we can look at skew-t charts to see whether we can actually get decent convection instead of a persistent blanket of stratus pushing in off the north sea. Mainly we need low 500mb heights and as big a difference between the sea surface temperatures and the 850s. 

In general easterly spells become less snowy and more cloudy the later we get into the season. 

Edited January 15, 2015 by Captain shortwave

[SMU]

Afraid I'm not following that Steve. As far as I can see the GFS has it re your trajectory. In any case the position of the front at T120 must be problematic as a glance at the METO fax will reveal.

Chart weatherbell

 

Sorry knocker I meant 132 not 120...

http://www.wetterzentrale.de/pics/Rmgfs1323.gif

 

06z Mean further south with the cold & further amplified, the slow progression SW continues....

 

My forecast track would hold the PPN not reaching the aforementioned counties...

S

 

T120 00z mean - had the -6c line over EA, the 114 06z has it now back over IOW up to Chester & across to NI.

Edited January 15, 2015 by Steve Murr

[karlos1983]

A cold N/N/W Pm flow to end the run, Turning North, But with so much uncertainty mid-term I would't take much notice, If at all..

 

Better positioned PV as well for further chances.

[karlos1983]

It's a job for nearer the time to be honest when we can look at skew-t charts to see whether we can actually get decent convection instead of a persistent blanket of stratus pushing in off the north sea. Mainly we need low 500mb heights and as big a difference between the sea surface temperatures and the 850s. 

In general easterly spells become less snowy and more cloudy the later we get into the season.

But surely sea temps are still pretty high given the lack of cold this winter?

[bradymk]

Quick question to anyone, does anyone know when the new hi-res GEFS is going to be made live to go along with the new GFS?

[swfc]

But surely sea temps are still pretty high given the lack of cold this winter?

Given the correct set up ie an easterly ,good 850s and a strong flow feb has produced epic falls of snow as i recall in the 70s and early 80s.

[Ali1977]

GEFS out to 180 and there are many different outcomes, none particually bad and some very good.....After day 4 anything could still happen although cold will be a guaranteed element for the majority of next week atleast.

[IDO]

Looking at the GEFS up to D8 and it is clear with a little tweaking either way the south could have rain or snow. The slider low is the main driver of the snow chances and the short London ens highlight that. There is still no pattern:

 

 

At the moment for the London region it looks about a 35% chance of snow from that slider low, similar to the 0z (for the D5-7 period). This far out it looks borderline:

 

  fergieweather
W COUNTRY Cold conditions will extend through all of next week, with a fine balance between seeing rain/sleet/snow across all of S England.
15/01/2015 11:37

 

  fergieweather
W COUNTRY CONT'D It'll be first rather prolonged cold phase since March '13. Temps rtn to about average gradually, within next ca. 10-15d
15/01/2015 11:42 Edited January 15, 2015 by i'm dreaming of...

[snowprincesspboro]

hi all, new to posting but not new to the site, been a lurker for a long time haha. just thought id ask a simple question please, so everyone is getting moaned at for talking about the where will it snow (obvs too far in fi) but why is it when its due in the next day or so, noone wants to mention it, i understand (esp in my location) the want (and need in some cases ) for snow, people will  look out to fi to find it and everyone is being bashed for doing so, but then when it comes into a reliable timeframe, noone is interested in it???? how comes when something exciting is showing up in fi, 0-72hrs seems to be ignored?

 

anyway i also wanted to say well done to everyone for keeping this site interesting and fun to read. im sure your efforts will soon be rewarded (fingers crossed with buckets and buckets full of snow haha) 

[Ali1977]

 

Looking at the GEFS up to D8 and it is clear with a little tweaking either way the south could have rain or snow. The slider low is the main driver of the snow chances and the short London ens highlight that. There is still no pattern:

 

graphe4_0000_306_141___Londres.gif

 

At the moment for the London region it looks about a 35% chance of snow from that slider low, similar to the 0z (for the D5-7 period). This far out it looks borderline:

 

  fergieweather

W COUNTRY Cold conditions will extend through all of next week, with a fine balance between seeing rain/sleet/snow across all of S England.

15/01/2015 11:37

 

  fergieweather

W COUNTRY CONT'D It'll be first rather prolonged cold phase since March '13. Temps rtn to about average gradually, within next ca. 10-15d

15/01/2015 11:42

 

Looks like next weekend will be the end of the real cold reading those, GEFS agreeing with that too.....Could be wrong though!

[MPG]

hi all, new to posting but not new to the site, been a lurker for a long time haha. just thought id ask a simple question please, so everyone is getting moaned at for talking about the where will it snow (obvs too far in fi) but why is it when its due in the next day or so, noone wants to mention it, i understand (esp in my location) the want (and need in some cases ) for snow, people will  look out to fi to find it and everyone is being bashed for doing so, but then when it comes into a reliable timeframe, noone is interested in it???? how comes when something exciting is showing up in fi, 0-72hrs seems to be ignored?

 

anyway i also wanted to say well done to everyone for keeping this site interesting and fun to read. im sure your efforts will soon be rewarded (fingers crossed with buckets and buckets full of snow haha) 

Because people always look for the breakdown rather than look out the window or go outside and enjoy it.

[Sussex snowstorm]

We ain't even in the cold yet and people are looking for a ending for it already, the models change daily, for instance tomorrow's modles will say different then today past even 96hours! It gives me headaches this model watching, but keeps me on my toes, All I know is that the cold is set in stone next week, for snow it's to early to say this far out, it's just a waiting game!

[SMU]

Remember the 06z ens suite will be poor, as is the 18z with NE blocking- however there is subtle swings afoot-

 

expect a full backtrack to cold circa day 8-12 by 12z tomorrow -

 

Looking forward to this afternoons runs with higher expectations than yesterday- & that's for all aspects-

* snow IMBY

* extended cold

* possible deep cold.

 

( * this pasted from retron on TWO this morning)

This morning's 0z ECM control run shows a Scandinavian High setup with the -10C 850 line moving in at T+264, then the deep cold air stays around for many until T+324 - although by then it's leaving Scotland. It's accompanied by NE'lies and it's no surprise that SE England especially is shown to have snow from it. Of course, that's so far out it's purely for interest's sake.

It's actually the snowiest control run yet this winter, with the majority of the UK already having seen snow by T+96.

 

S

Edited January 15, 2015 by Steve Murr

[chionomaniac]

hi all, new to posting but not new to the site, been a lurker for a long time haha. just thought id ask a simple question please, so everyone is getting moaned at for talking about the where will it snow (obvs too far in fi) but why is it when its due in the next day or so, noone wants to mention it, i understand (esp in my location) the want (and need in some cases ) for snow, people will  look out to fi to find it and everyone is being bashed for doing so, but then when it comes into a reliable timeframe, noone is interested in it???? how comes when something exciting is showing up in fi, 0-72hrs seems to be ignored?

 

anyway i also wanted to say well done to everyone for keeping this site interesting and fun to read. im sure your efforts will soon be rewarded (fingers crossed with buckets and buckets full of snow haha) 

Hi and welcome spp. I have started a cold discussion thread here for further info with this type of discussion.

 

https://forum.netweather.tv/topic/82292-upcoming-cold-spell-discussion/

Edited January 15, 2015 by chionomaniac

[Pennine Ten Foot Drifts]

 

Looking at the GEFS up to D8 and it is clear with a little tweaking either way the south could have rain or snow. The slider low is the main driver of the snow chances and the short London ens highlight that. There is still no pattern:

 

graphe4_0000_306_141___Londres.gif

 

 

Aye, and looking at the ensembles in general, scatter starts to be very noticeable from 19-20/01 onwards. In other words even from the beginnings of the key slider low as it starts its journey from west of Iceland to (eventually) northern France the models are really not hugely consistent as to how things will develop. So given how critical the path of this low is to cold/snow outcomes, and given how much uncertainty there is about that path (as well as orientation and intensity), then it's pretty clear that we're still very much in the realms of 'probability-casting'. I would suggest it'll be a few days yet before we can have a reasonable degree of confidence, and therefore start to make reasonably accurate predictions about likely outcomes, regarding what is in store after next Monday, (other than of course that it almost certainly will get noticeably colder, which is about all we can say with any degree of certainty right now).

[Snowmaggedon]

Remember the 06z ens suite will be poor, as is the 18z with NE blocking- however there is subtle swings afoot-

 

expect a full backtrack to cold circa day 8-12 by 12z tomorrow -

 

Looking forward to this afternoons runs with higher expectations than yesterday- & that's for all aspects-

* snow IMBY

* extended cold

* possible deep cold.

 

( * this pasted from retron on TWO this morning)

 

S

Hi Steve do you expect a strong easterly feed to develop as next week progresses which the models are already suggesting?

[johnholmes]

In terms of the 500mb flow for days 6-10 after we have got to day 6, using the synoptic models, then the link below shows what EC-GFS are suggesting, otherwise there seems not a lot to alter the post I made (261 page 14) last evening.

Enjoy the cold those that like the cold, snow for many on low ground at some point in the next 10 days. Forget expecting any model to give you much accuracy more than 24h out probably only 12, but they will, IF consistent, give a general idea of where to look for the most likely areas.

http://mp1.met.psu.edu/~fxg1/ECMWF_12z/hgtcomp.html

Sure is a different mid January to last January. Who knows what February might bring.

Hi Steve do you expect a strong easterly feed to develop as next week progresses which the models are already suggesting?

 

Not Steve but if the anomaly charts just posted are anything like the upper flow turns out to be that is a probability I would suggest. 50%+ at the moment but the NOAA version, often the closest to the actual is not that keen from what I remember last evening.

[ukpaul]

hi all, new to posting but not new to the site, been a lurker for a long time haha. just thought id ask a simple question please, so everyone is getting moaned at for talking about the where will it snow (obvs too far in fi) but why is it when its due in the next day or so, noone wants to mention it, i understand (esp in my location) the want (and need in some cases ) for snow, people will  look out to fi to find it and everyone is being bashed for doing so, but then when it comes into a reliable timeframe, noone is interested in it???? how comes when something exciting is showing up in fi, 0-72hrs seems to be ignored?

 

anyway i also wanted to say well done to everyone for keeping this site interesting and fun to read. im sure your efforts will soon be rewarded (fingers crossed with buckets and buckets full of snow haha) 

 

The main reason is that, with a couple of days to go then the pattern is set and, usually, little will change. At this point it's over to the regional threads if you want to talk about what you are or aren't getting or the ramps/moans thread if you just want a countrywide broadcast ramp/moan.

 

The model thread isn't focused on what will happen now, rarely on what will happen tomorrow.

[ukpaul]

Quick question to anyone, does anyone know when the new hi-res GEFS is going to be made live to go along with the new GFS?

 

Q3 apparently, so expect it around Summer/Autumn.

[SMU]

Hi Steve do you expect a strong easterly feed to develop as next week progresses which the models are already suggesting?

 

Yes -80%

 

I am doing a round up post before the 12's however 2 key things to look for which I will detail later-

 

The usual failing of our Easterlies is not enough low heights to the SE, that's not the case here -  the easterly is odds on favourite, its the longevity that's the question, high pressure is required to the NE for that to happen-

 

We need to see if we can get a good link up from the high to the North of the atlantic & fledgling High over scandi

Also I am looking at the angle of cold dropping into scandi at 144- 

 

regards

Steve

[alexisj9]

But surely sea temps are still pretty high given the lack of cold this winter?

That's a good thing, the temp difference between the sea and the cold air causes the convection that drops the snow showers.

[Timmytour]

Looks like next weekend will be the end of the real cold reading those, GEFS agreeing with that too.....Could be wrong though!

With reference to this being the coldest spell since March 2013.....I'm a little disappointed April 2013 gets ignored.....the mean CET for the first week didn't rise above 4c.  tbh I'm not sure we are going to get seven consecutive days where that's the case coming up although it certainly will be colder on some of those days

[Met4Cast]

Do people on these forums learn nothing over the years?

 

The cold spell hasn't really started yet and you're already talking about a return to Westerlies in over 10 days time? Lets take 2010 for an example, the models were continuously forecasting a return to milder weather at around the 10 day mark and with every run it was being pushed back, and back.

 

Why you're putting so much confidence in the return to milder weather at a distance of 10-15 days when we haven't even got detailed for this weekend/early next week pinned down yet is beyond me.

 

00z ECM, GFS and the 6z GFS are incredible runs. Details on snow remain uncertain but synoptically, they're a million miles away from anything we saw last year.

[SMU]

Last one-( & slightly off topic but relating to the above post )

 

I expect the Mean for Scotland for next week to be between -2c & -5c.

 

S