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Posted
  • Location: Weston Super Mare , North Somerset
  • Location: Weston Super Mare , North Somerset

With regard to Mon/Tue:

I think the GFS ensambles illustrate what we are seeing with these charts - total uncertainty only 2-3days out.

See the circled area for potential 2m temps for Wilts (choosen as its central southern UK; an area that highlights how marginal things are).

You will very rarley see so much disagreement with only 2-3days to go.

Another example:

Last 4 runs for Wiltshire for Monday day and Tue Night:

18Z

Heavy Rain Mon

Light Rain Tue

00z

Heavy Sleet Mon

Heavy Snow Tue

06z

Light rain Mon

Heavy Sleet Tue

12z

Heavy Sleet Mon

Heavy Snow Tue

The North/East/South/West positioning differential of the Monday and Tuesday lows are as follows:

circa t96 = +/- 250miles

circa t72 = +/- 200miles

circa t48 = +/- 125miles

circa t24 = +/- 50miles

Im a betting man, and i wouldnt put a bet on either rain or snow at this stage!

Would agree with most of that , We had a surprise 2 hours Heavy Snowfall (Massive Flakes) In Leicester this afternoon and it wasn't forecast . Settled as well out of the City Center . I think GFS thinks Sunday's ppn will be Snow in the midlands as by Midnight it has temps shooting down to -5 still with ppn about so It must be including Snow cover. Monday I am not so sure about , the low track is not nailed by a long shot , But as shown it has a very large warm sector with it and if the Mild air beats the front it will be a very wet day .

As for your bettering Comment , I have just placed a bet on Leicester Thrashing Plymouth tomorrow , but you never know the way the models are at the minute it may get called off due to a Snow logged pitch . :)

The advisory for snow on monday covers more than just the midlands. The fax would suggest a repeat of yesterday with Norh West Mids favoured for snow with rain on the SE side of the low. As this pulls away in a SE direction more areas will see snow including East mids and East Anglia. It looks very marginal for anyone from Midlands south and I wouldn't be optimistic of snow after sunday if I lived south of the M4.

Yes I know I just couldn't be bothered to write all the areas in , I should have said Midlands Northwards. The main point I was trying to make was about the Thur/ Fri comment you made as temps are going to dip tonight where showers have fallen there is an obvious Ice Risk .

As I said in my previous comment it is probably going to be late Sunday before we can attempt to call Monday's Event . I remember a couple of years back in Feb when a low was suppose to go into France but changed track and traveled NE and gave most of the UK Heavy Snow. The track change was so late that it wasn't shown by any of the models until after it happened.

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Posted
  • Location: portsmouth uk
  • Weather Preferences: extremes
  • Location: portsmouth uk

my thoughts towars the models have not changed some are showing cooler air with possibility of snow events although marginal apart from nothern scotland also i see here the risk decreasing fairly quickly from mid week onwards,

and pressure build in the med area and around southern europe pushing milder ridges towards us although never really getting right over us but this is helping to push systems sw to northeast and eventually west to east,

and deep cold air now is retreating towards the north more and more with the deepcold in scand retreating aswell.

im pretty confident our long cold winter is coming to an end,

maybe out with a bang towards midlands and ireland and scotland where the east wind is blowing infact nearly acroos the northern alantic perhapes futher than northern scotland,

so this pretty good keeping them sst down in the northern alantic,

so in my humble opion this means although theres scope for the jet to return north i think we wont be seeing it going to far north for a very longtime as this could be a part of a prolonged cycle.

but over all i think spring is coming now and i expect it to be pretty active spring aswell,

in the near future though pretty dam white for a little while then becoming pretty dam wet windy and lively as week head through the new working week and becoming slowly milder from the south but nothing blowtourch yet.:)

The way the models are performing the low could be 300miles or more out in all directions from

what is being shown at present so no one is excluded I think.

A much more encouraging run from the ECM tonight and IF the lows are slightly more

suppressed then this would be a very wintery run for many.

Tentative signs of some good blocking to the northeast in the FI part of the run.

fi is fi if the models are performing bad now then why bother with fi please.

explain why you are so fixed on blocking?

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Posted
  • Location: Liphook
  • Location: Liphook

The advisory for snow on monday covers more than just the midlands. The fax would suggest a repeat of yesterday with Norh West Mids favoured for snow with rain on the SE side of the low. As this pulls away in a SE direction more areas will see snow including East mids and East Anglia. It looks very marginal for anyone from Midlands south and I wouldn't be optimistic of snow after sunday if I lived south of the M4.

Yep thats true though ther eis enough uncertainty to not be quite sure wi9th how this evolves, take that low 70 miles further SE and it brings all but the very far south coast into play. Based on the 12z models though the area that got snow yesterday would very roughly be the line I'd use this time as well, though the west Midlands would be favoured though as you say due to the track of the low and colder air coming in.

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Posted
  • Location: Bristol, England
  • Location: Bristol, England

Wow, it would seem next week could see several snow events, as a succession of low pressure systems move across or just to the south of the UK.

Monday looks very interesting for many places. Massive temperature gradient about 10C in the English Channel and only

-1C over parts of SE Wales and SW Midlands.

I admit I'm disappointed about the weekend - yesterday they were predicting mainly sunny weather,

now Saturday and Sunday morning could see a wintry mix instead.

Very interesing times ahead!

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Posted
  • Location: st albans
  • Location: st albans

the 12z ecm in fi is pretty crazy in the nw atlantic as part of the p/v is ejected from n canada and heads se towards iceland. of course it wont happen but fantastic to look at the neg mid twenties uppers draining into the area south of greenland.

post-6981-12666134200417_thumb.png

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Posted
  • Location: swansea craig cefn parc 160 m asl
  • Location: swansea craig cefn parc 160 m asl

Yep thats true though ther eis enough uncertainty to not be quite sure wi9th how this evolves, take that low 70 miles further SE and it brings all but the very far south coast into play. Based on the 12z models though the area that got snow yesterday would very roughly be the line I'd use this time as well, though the west Midlands would be favoured though as you say due to the track of the low and colder air coming in.

Fair enough but what output do met use but there weather warning extends a far greater range than thursday snow.
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Posted
  • Location: hertfordshire
  • Location: hertfordshire

absolutely blast ive hearing this tune everyday for weeks from cc although i respect his idears i think it can in the end become rather dissapointing for some of the less expeienced members who think his predictions will happen.

fi is fi if the models are performing bad now then why bother with fi please.

explain why you are so fixed on blocking?

In regards your first question the reason we are seeing cold weather now is in part because

of high pressure to the northeast. On many occasions I have given data to back up my reasoning,

if you look through previous model threads you will see this.

My timing may be off with regards to seeing a substantial block developing to our north and north

east but when dealing with MMW and downward propagating negative zonal winds and warming

(blocking) timing issues are still very much a guessing game. By the turn of the month or there abouts

we will be feeling the effects of this blocking. The models will start to show such synoptics anytime now.

In regards to your second question I said a couple of days ago along with a few others that the models

would be volatile and unreliable at the moment due to these meandering lows and the splitting of the

vortex and trailing pieces of energy. Because of this it is not worth looking beyond t72 at the moment

and certainly no further than t144.

Obviously a significant error in the short range will be greatly compounded further down the line.

I said in a post this morning that my CET guesstimate will be way out even though we are going to

have a cold cet return for the month and for the same reasons that I predicted a very cold month just

without the potency of cold I was expecting. It would not have taken much earlier in the month or now

even to have had a much colder month than we are having.

The earlier post I made showing the increasing levels of ozone to the north and northeast is another

signal along with the warming over Svalbard and Scandinavia that blocking in this area is IN MY OPINION

going to happen.

Cheers.

Edited by cooling climate
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Posted
  • Location: Glasgow, Scotland (Charing Cross, 40m asl)
  • Weather Preferences: cold and snowy in winter, a good mix of weather the rest of the time
  • Location: Glasgow, Scotland (Charing Cross, 40m asl)

Hmmm, just wishing THIS was the UKMO at 72 hours http://91.121.94.83/modeles/wmc/run/wmc-1-120.png

'drool'

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Posted
  • Location: Manchester City center/ Leeds Bradfor Airport 200m
  • Location: Manchester City center/ Leeds Bradfor Airport 200m

I could really see this setup we have now dragging on for ages, similar to an Atlantic driven winter (one that you can't get rid of). Perhaps lasting into March, whether this a good thing or not it remains to be seen, for some we would be stuck in a rut for others a gold mine. It looks like been wet in the South with the odd snow, snowy in the Midlands/Wales with rain at times, and Snowy in the far south of Northern England. With Scotland's and the far north of England/Ireland been predominantly dry.

Edited by 10123
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Posted
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.
  • Weather Preferences: Snow and storms
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.

im pretty confident our long cold winter is coming to an end,

explain why you are so fixed on blocking?

I am also confident bb that our long cold winter is coming to an end as well. In fact I give the cold lasting no more than 9 more days this winter with still the ability to produce more surprise snowfalls in this time.

And after you may ask? Well I see spring occurring. And if the propagation of negative mean zonal winds occurs to the troposphere then this could also start off well below average.

post-4523-12666140487517_thumb.gif

The main question that I wonder about is whether that any resultant northern blocking will affect us. I think that cc is too confident that it will, but I see the potential but there are still hurdles to overcome which may not be achieved. The 100 hPa stratospheric charts are now looking less favourable than they did a couple of days ago. So, whereas the start of March may come in below average I am less sure now that a big freeze is likely, but I also don't see a rapid warm up either.

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Posted
  • Location: Manchester City center/ Leeds Bradfor Airport 200m
  • Location: Manchester City center/ Leeds Bradfor Airport 200m

Yeah I agree I do think there will be a Easterly/North Easterly, but I could see us been stuck in this pattern for a while thus delaying the easterly till early March. Whether this easterly is potent enough remains to be seen but I'm confident we will see winds coming from the east at some point, be it for a few days or a few weeks.

Also "bad boy" I think you're been unfair considering you have been singing Atlantic driven weather which has yet to materialise, if we had gone by your IMBY posts everywhere in England would have seen rain, but all I have seen everyday is snow.

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Posted
  • Location: Liverpool
  • Location: Liverpool

"Hi,

Is the situation for next week best described as a "battleground" situation with a low from the SW moving into colder air from the north, is it similar synoptically to February 1996 or March 2006 when parts of Northern England ended up with a lot of snow?

Luke

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Posted
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.
  • Weather Preferences: Snow and storms
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.

In regards your first question the reason we are seeing cold weather now is in part because

of high pressure to the northeast. On many occasions I have given data to back up my reasoning,

if you look through previous model threads you will see this.

My timing may be off with regards to seeing a substantial block developing to our north and north

east but when dealing with MMW and downward propagating negative zonal winds and warming

(blocking) timing issues are still very much a guessing game. By the turn of the month or there abouts

we will be feeling the effects of this blocking. The models will start to show such synoptics anytime now.

In regards to your second question I said a couple of days ago along with a few others that the models

would be volatile and unreliable at the moment due to these meandering lows and the splitting of the

vortex and trailing pieces of energy. Because of this it is not worth looking beyond t72 at the moment

and certainly no further than t144.

Obviously a significant error in the short range will be greatly compounded further down the line.

I said in a post this morning that my CET guesstimate will be way out even though we are going to

have a cold cet return for the month and for the same reasons that I predicted a very cold month just

without the potency of cold I was expecting. It would not have taken much earlier in the month or now

even to have had a much colder month than we are having.

The earlier post I made showing the increasing levels of ozone to the north and northeast is another

signal along with the warming over Svalbard and Scandinavia that blocking in this area is IN MY OPINION

going to happen.

Cheers.

Whereas I agree with a lot of your post cc, I think that this last bit may be a little bit too simplistic for more complex dynamical stratospheric to tropospheric interactions that are likely to occur during this MMW. The stratospheric FI charts have been changing significantly and these can be relied on no more than the tropospheric charts.

I know that you have seen the potential for a serious cold outbreak this month and in truth so have I. But that is all it is, and with such stratospheric and tropospheric model volatility at present, neither you or I can say that it will definitely happen.

There is definitely a chance though.

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Posted
  • Location: Manchester City center/ Leeds Bradfor Airport 200m
  • Location: Manchester City center/ Leeds Bradfor Airport 200m

Is the situation for next week best described as a "battleground" situation with a low from the SW moving into colder air from the north, is it similar synoptically to February 1996 or March 2006 when parts of Northern England ended up with a lot of snow?

Battle ground scenario ATM, could change in the coming week.

Edited by 10123
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Posted
  • Location: Portishead
  • Location: Portishead

very sad to be on here and looking at charts (but am off to pub after this post!):

up to t39 so far and i think the gfs will go for a similar run to 12z onwards, however slightly further north prognosis on the lows on monday and tuesday, but with cooler temps surrounding. still very marginal, southern yorks winning.

only a thought.

ch'o

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Posted
  • Location: portsmouth uk
  • Weather Preferences: extremes
  • Location: portsmouth uk

I am also confident bb that our long cold winter is coming to an end as well. In fact I give the cold lasting no more than 9 more days this winter with still the ability to produce more surprise snowfalls in this time.

And after you may ask? Well I see spring occurring. And if the propagation of negative mean zonal winds occurs to the troposphere then this could also start off well below average.

post-4523-12666140487517_thumb.gif

The main question that I wonder about is whether that any resultant northern blocking will affect us. I think that cc is too confident that it will, but I see the potential but there are still hurdles to overcome which may not be achieved. The 100 hPa stratospheric charts are now looking less favourable than they did a couple of days ago. So, whereas the start of March may come in below average I am less sure now that a big freeze is likely, but I also don't see a rapid warm up either.

thanks for that chiono.

its always a possibility it could pan out ok for cc but it has been the case that after jan the strat although has had an influence on our weather type it has not gone completely to plan after the jan cold spell,

dont get me wrong it certainly been a exciting winter and im very intrested already how next winter may pan out im somewhat hoping solar outputs dont become to high and atm still pretty below the cycle 23 22 averages.

but ofcoarse the here and now is messy and pretty confident that if thease systems wernt causing all thease chaos then it would be easy to predicted what happens next,

but its all a lesson to be lernt and how the strat has thease effects on our weather is becoming a very valuable tool in forecasting as is gp and his thoughts,

so all in all very messy wet down here on the dare i say sunny southcoast and some snow events still possible although over the coming week turning much more marginal.

great stuff though.:rofl:

Edited by badboy657
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Posted
  • Location: Bristol, England
  • Location: Bristol, England

The 18Z is looking absolutely spot on for the South West for Monday morning, but wouldn't wish to be driving to work in the resultant snow if that chart came off!

Don't drive anyway but that is beside the point really.

Edited by Thundersquall
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Posted
  • Location: Liphook
  • Location: Liphook

Still some big uncertainties for Sunday, the GFS gives an event for the Midlands on the leading part of the front, Wales and the north of England throughout...meanwhile the 18z NAE looking at the spot totals is even further *south* then its 12z run with the heaviest precip over my location...hopefully not as I've got a train to catch on Sunday, it can go away further north as far as I'm concerned.

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Posted
  • Location: Glasgow, Scotland (Charing Cross, 40m asl)
  • Weather Preferences: cold and snowy in winter, a good mix of weather the rest of the time
  • Location: Glasgow, Scotland (Charing Cross, 40m asl)

'Sigh' useless 18Z for Scotland, with really just cold, dry weather continuing. It is rather frustrating to see the potential has shifted a bit further south at the moment but I don't know if this will be the final outcome.

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Posted
  • Location: st albans
  • Location: st albans

Still some big uncertainties for Sunday, the GFS gives an event for the Midlands on the leading part of the front, Wales and the north of England throughout...meanwhile the 18z NAE looking at the spot totals is even further *south* then its 12z run with the heaviest precip over my location...hopefully not as I've got a train to catch on Sunday, it can go away further north as far as I'm concerned.

NNM and GFS both show this precip as rain sunday pm anyway Kold. N24 mentioned rain showers in the south so even if the NAE shows it as snow, its a bit 'out on a limb'.

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Posted
  • Location: Bristol, England
  • Location: Bristol, England

Not getting my hopes up just yet, but Tuesday on the 18Z shows a massive Channel Low with monster amounts of precipitation centered over the West Sountry / SW Milands!

Looks like next week could indeed get very interesting! There I was thinking I've had enough of the snow, was rather hoping for Spring to make an early appearance.

post-3528-12666168085417_thumb.pngpost-3528-12666168263817_thumb.pngpost-3528-12666168402717_thumb.pngpost-3528-12666168563717_thumb.png

Edited by Thundersquall
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Posted
  • Location: Manchester City center/ Leeds Bradfor Airport 200m
  • Location: Manchester City center/ Leeds Bradfor Airport 200m

Another snow event shown for the Midlands, alot of uncertainty to the northern extent of these lows so still so nothing set in stone, I could see either a big shift south or north of the low on Monday.

prectypeuktopo.png

Edited by 10123
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Posted
  • Location: Bristol, England
  • Location: Bristol, England

Minus 12C on Wednesday night for parts of Southern England? :whistling: The 18Z charts are a stunner! Maybe a bit into FI but it is good to look at all the same.

Edited by Thundersquall
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Posted
  • Location: North Bromsgrove 185m (moved 100m lower...)
  • Location: North Bromsgrove 185m (moved 100m lower...)

3 channel lows between Mon and Thu! Just to see such output within the 7-day timeframe is impressive enough. To see even one come off in reality would be a bonus of course.

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