Model Output Discussion

[grab my graupel]

A fresh thread to discuss the latest Model Output.

Please remember to utilise the the various other threads for any non Model related dicussion. And above all, keep it friendly

All the up to date Model Output, plus much more, can be found in the Netweather Data centre: http://www.netweather.tv/index.cgi?action=charts;type=home;sess=

Please continue

[LomondSnowstorm]

Im hoping for member

Interesting that what some of the ensembles show is the intial LP move E and then LP to our S pulls in colder E,lys.I agree with Niok we do need the ECM/GFS to move the pattern further E. Otherwise it will be marginal snow for most of us followed by it becoming less cold.So im not saying this due to my location but because we would all benefit as the cold spell would be more prolonged. I have to say though this isn't exactly common what the models are suggesting. So I expect the models to struggle with this upcoming pattern.

It does look as though this will bring a welcome top up to the rather limited store of cold air to the northeast at the moment

Here

Here

would like to see the pattern further east as it would certainly extend and increase the severity of the spell for all but my area is probably less vulnerable to slight changes in the position of the pattern than others.

A reasonable control run also Here

Also nice parallel control too. Here

LS

[Weather-history]

Shhhh!

Has something happened? Is the outlook so boring and beneign that people cant be bothered? I need something to read with my morning coffees and fags, bored of chats about Carol Kirkwoods hat.

(Now theres a post tailor made for deleting....)

Why don't you look yourself and give an opinion

http://www.wetterzentrale.de/topkarten/fsavneur.html

Edited February 10, 2010 by Mr_Data

[MKN]

http://www.accuweather.com/video-on-demand.asp?video=19668940001&title=Another%20Blizzard!&ctr=2

you could watch that and then you realise is it worth commenting on the possibility of 2-5cms?

[scottishandy]

Not much happening in the models unless you live in SE corner of Kent.

Other than a couple of interesting looking LP's dropping in from the North in a weeks time on the euro outputs. Not entirely used to meteociel format but they look cold and interesting to me.

[Frosty.]

Why don't you look yourself and give an opinion.

Well my take on the 00z is that the gfs is trending even further west in FI so eventually the pattern goes pear shaped, arctic air flooding into mid atlantic is not what I want to see!! Next week would still be rather cold and unsettled but snow would be restricted to the north and mainly on high ground and eventually milder air is easily allowed to spread in from the southwest. I don't like the ecm or ukmo trends either, too far west which appears to be the trend.

We should all go to east kent tonight as this is the only part of the uk to be in the firing line of heavy snow showers with drifting in fresh to strong NE'ly winds, what a huge downgrade from what the models showed several days ago.

[len]

Unfortunately the models seem to be settling on a very iffy trajectory for the Low descending from the North.

Somehow the High gets away NW, without us ever getting into the Arctic shot!

It's very reminiscent of post Christmas. As the Low descends over us it keeps the real cold shot out in the Atlantic. North West will be best if this happens, and Western Ireland as well, which will be a replay for them to.

I know the Toppler-Northerly usually deflects East at the last moment, but this is not the same scenario and indeed it played out as advertised last time. Only hope is some teleconnections referred to on the Tech Thread that don't support this rapid retrogression

[mountain shadow]

Well, i guess it's quiet on here as the current cold spell isn't really delivering for the south east and the one for next week probably won't either.

Fo northern ireland, much of scotland, north east england, north west england and north wales it continues to look excellent for heavy snow next week with frequent snow showers and longer spells of snow. Obviously the higher you are the more likely the snow will stick.

Cross model agreement on the trough being situated around northern scotland at T+144, after that is FI.

[bluearmy]

only output not too far west next week is the GEFS. the rest of it going down a slippery slope. ebbs and flows but dont expect a flood of optimisim in here before the 12z's and probably beyond. wanted to see more of an east trend today or at least yesterdays 12z's repeat.

[karyo]

I was hoping that the models would have adjusted the pattern eastwards but instead they moved it west again! There is no northerly on the ECM anymore I'm afraid. In fact the winds are coming from a generally southerly direction as the low dives from Scotland southwestwards. Cold enough for snow for a time but then rain and a rise in temperatures. FI is horrible looking!

Karyo

[Weather-history]

Well my take on the 00z is that the gfs is trending even further west in FI so eventually the pattern goes pear shaped, arctic air flooding into mid atlantic is not what I want to see!! Next week would still be rather cold and unsettled but snow would be restricted to the north and mainly on high ground and eventually milder air is easily allowed to spread in from the southwest. I don't like the ecm or ukmo trends either, too far west which appears to be the trend.

It looks a bit like how the pre-Christmas cold spell went with a low coming down from the north

Edited February 10, 2010 by Mr_Data

[Frosty.]

It looks a bit like how the pre-Christmas cold spell went with a low coming down from the north

Very interesting, however, if the trend keeps moving westwards, next week will begin to turn less cold with rain and the only snow will be on the top of a hill or mountain.

[cooling climate]

only output not too far west next week is the GEFS. the rest of it going down a slippery slope. ebbs and flows but dont expect a flood of optimisim in here before the 12z's and probably beyond. wanted to see more of an east trend today or at least yesterdays 12z's repeat.

Must admit I was quite optimistic before seeing the models this morning, but we are still

talking a week away so nothing is nailed yet.

I think with all the northern blocking and a true Greenland high developing cold and snow

lovers in the UK could count themselves rather unlucky if we do not get on the right side

of any troughs or low pressures to deliver another potent blast of wintry weather in the next

three to four weeks.

Take this cold spell for instance we wanted the high further northwest but it does not look likely

now, then as the pattern retrogresses lol, we want everything shunted further southeast.

Still as I say the pattern is not nailed yet + we have sleet and snow showers to contend with in

the east today and some possible significant snow for the southeast corner tonight.

[Pennine Ten Foot Drifts]

Well, i guess it's quiet on here as the current cold spell isn't really delivering for the south east and the one for next week probably won't either.

Fo northern ireland, much of scotland, north east england, north west england and north wales it continues to look excellent for heavy snow next week with frequent snow showers and longer spells of snow. Obviously the higher you are the more likely the snow will stick.

Cross model agreement on the trough being situated around northern scotland at T+144, after that is FI.

Would tend to agree, although it's now starting to get more marginal even for more favoured areas, and if over the next three or four days the pattern shifts further west by even just another 100 miles (which is nothing really) then it's rain/sleet for virtually everyone next week. Even the GFS 00z, which has probably the best setup of the main models, is showing warm sectors mixed into that trough, and as we saw pre-Xmas, and as Mr Data has already pointed out, it doesn't seem to need much in the way of warm sectors for things to be the wrong side of marginal in a setup like this.

[nick sussex]

As that saying goes too much of a good thing can be bad for you! in this case the reverse zonal winds have backed the pattern so far west that as we've seen from this mornings model output the cold air spills into the Atlantic.

These reverse zonal winds are often welcomed as they can help with cold patterns but here we see a western based negative NAO with a low stuck over the UK.

However even allowing for this how the low sets up near the UK isn't quite certain yet. The ECM De Bilt ensembles for the Netherlands still look okay which suggests that northern areas of mainland Europe still look on the cold side. It could be that the trough sets up so far west that a se flow is introduced, then its how this low interacts with low pressure over Iberia that could still develop slightly more interest than is currently shown.

I really can't see a massive eastward shift in the pattern but theres room for manouevre in terms of the phasing between the UK and Iberian lows and whether pressure can build out of the Arctic and drive the pattern se in the further outlook.

Edited February 10, 2010 by nick sussex

[Frosty.]

WOW it's so quiet in here, is everyone going to east kent tonight on the snowwatch tour bus

General model agreement that the rest of this week including the weekend will be mainly dry but rather cold with plenty of sunshine, light winds will increase the frost risk and fog formation in places, a few wintry showers will keep pecking away at eastern coastal areas once the snow clears kent tomorrow morning. Next week is currently looking very unsettled with spells of rain and generally cyclonic conditions, temps recovering to near average but maybe cold enough for snow on hills, especially in the north.

[aspire27]

Wow 13 posts since midnight.

Seems to me, as i said before, that this month has been a case of chasing the cold that has never been in the reliable time frame. Looks like the rest of the month will be the same, with only 18 days of winter left (in my book) this Feb is going out with a big wimper.

A very big turn around in the models (showing in the reliable) is now needed, looking at charts in FI caught us out last week in regards to this weeks downgrades and again last night and on moday people saying next week is the week to watch.

Chasing cold in FI is mad, if we cannot get any cold in the reliable nailded first.

IMBY this week has been fine dry and sunny so far with temps just below average, feels like spring in the sunshine....out of the wind mind you.

[TEITS]

I really can't see a massive eastward shift in the pattern but theres room for manouevre in terms of the phasing between the UK and Iberian lows and whether pressure can build out of the Arctic and drive the pattern se in the further outlook.

Yes that is what im hoping for.

I will add that although the pattern does look similiar to Dec the actual weather on the ground will differ hugely. If we use Dec 23rd as an example despite the warmer upper temps my surface temps remained around freezing until around the 26th. However this time my temps are likely to be around 5-6C. Some will ask why is this? Well its a combination of the E,ly beforehand being much colder which resulted in deep lying snow in my area combined with the short daylight hrs.

Have to say I do feel rather short changed looking at the models. What could of been 2 weeks of very wintry weather has turned into wintry showers for this week followed by cold rain next week. Just hope the output changes more favourably.

[nick sussex]

Yes that is what im hoping for.

I will add that although the pattern does look similiar to Dec the actual weather on the ground will differ hugely. If we use Dec 23rd as an example despite the warmer upper temps my surface temps remained around freezing until around the 26th. However this time my temps are likely to be around 5-6C. Some will ask why is this? Well its a combination of the E,ly beforehand being much colder which resulted in deep lying snow in my area combined with the short daylight hrs.

Have to say I do feel rather short changed looking at the models. What could of been 2 weeks of very wintry weather has turned into wintry showers for this week followed by cold rain next week. Just hope the output changes more favourably.

I tend to agree, even in such a good winter there have been quite a few near misses and the easterlies have generally been over modelled in terms of length and severity.

Generally the signal for retrogression has meant that the easterlies are being squeezed out by troughing developing over Scandi and this pattern has played out for the winter as a whole.

Even though I'm not that keen on todays model output there is still some uncertainty with low pressure near the UK and Iberia, some of the ensembles pull these further south, some phase these into one low this will make a difference.

[Polar Continental]

Can someone take away the model controls from Ian Brown, lol, and hand them over to Steve M.

The models are continuing with the jet shifted well to the south of the UK, northern blocking is very evident for the foreseeable future, yet we it seems somehow we manage to get the mildest possible solution out of the scenario. So I can understand the frustration from the cold lovers on here, as we have a unique Atmospheric set-up, something that has been missing for many years and we seem to end up with none starter really.

But at the end of the day, the UK has to be quite lucky to end up with an especially cold set-up, because of our position and exposure to the warm Atlantic, so this projected set-up should not come as a surprise really.

Obviously there is time for the high to regress just far enough westward and still allow a cold northerly plunge next week.

The 0z GFS shows the better route to a colder solution, but is far from perfect. The ECM regress the high so far north west that the low coming down from the north ends up the wrong side of the UK and produces damp southerly winds for the bulk of the UK. The GEM follows the ECM. The UKMO is similar to the GFS, projecting the low to centre over the UK.

ECM low ends up the wrong side of UK

0z GFS, not bad, but not perfect.

[Weather-history]

This type of scenario could easily develop into this and the northern and Irish members remember this one very well.

[Duane S.]

+1 with what some others have said above.

With these synoptics it really would be unlucky for us to miss out on a couple of weeks of cold - very cold leading to snowy weather. A strong SSW leading to reversed zonal winds and a retrogressed HP to Greenland sounds, on the face of it, to be perfect BUT if the models and current trends are to be believed then it certainly doesn't look overly good. But whilst we have these synoptics it wouldn't take a massive shift to pull things back in our favour. Still time to see a new trend and it would hardly be the first time this winter!

[cooling climate]

Just had a very intense snow shower here in Hertfordshire about 15minutes ago

which lasted about 10 minutes and made everything temporarily white barring the

main roads.

It may be quite an eventfull day in the east and southeast today.

The 06z GFS run slightly further east again at t114, at t120 I am still surprised as

to why the low in the northsea will not continue to move southeast.

[D KARLSON]

I tend to agree, even in such a good winter there have been quite a few near misses and the easterlies have generally been over modelled in terms of length and severity.

Generally the signal for retrogression has meant that the easterlies are being squeezed out by troughing developing over Scandi and this pattern has played out for the winter as a whole.

Even though I'm not that keen on todays model output there is still some uncertainty with low pressure near the UK and Iberia, some of the ensembles pull these further south, some phase these into one low this will make a difference.

Although i agree ,theres just one problem the models for next week are only forecasts and will most definitely change whether to a milder option or colder is unclear even though the basic set up will be much the same.

As i said there is a lot of scope for change and even just the slightest change in the postioning could bring a lot of snow to northwestern parts withn this risk extending southeast according to error.

I think the MET will be following this one closely as there is quite a number of different solutions to thios synoptic set up

[Rollo]

"Cooling Climate" says in his post above "he cannot understand why next weeks low pressure system insists at this stage on appearing to go farther west than he thought it would", I have to say that I concur and would like the views of some of our resident experts. I know the weather will do what the weather will do but certainly the norm is for lows to move on a south-easterly track down the North Sea.