Model Output Discussion

[Freezing-Point]

What I do like about the ECM and the same can be said for other models runs is the first hurdle towards a very cold spell in the UK is already in place. Some of you might be wondering what im on about but what im referring to is a bitter cold pool to our N/NE.

One of my gripes with this winter and the same can be said in recent winters is a general lack of extensive very cold pools to our N/NE. What we have been seeing is small pockets of cold pools around -10C/-15C. This is why the E,ly in Jan actually became warmer!

I have always said at times the synoptics prior to a cold spell are just as important as to the synoptics bringing the actual cold spell itself. For example Feb 05 E,ly was very weak because prior to this the continent was subjected to mild S/SW,lys. The other extreme is Jan 1987 when an incredibly cold pool spread S prior to backing SW across the UK.

So with this in mind the model output does suggest a cold pool will be to our N/NE so thats the first hurdle out of the way. The next hurdle is getting the right synoptics so this backs SW. Now the 12Z ECM is a very good run because we do see the colder temps back SW. However it could be better and it would only require the LP to track slightly further S to back an even colder E,ly flow. Also worth mentioning that the chance of a Scandi HP remains possible as has been shown on some of the GEFS ensembles.

If the ECM continues with this trend it could get very exciting. However this LP is reminding me of my ex girlfriend i.e extremely unpreditable!

A great post TEITS. This winter has been good but has missed the potential of some sub-15 pools. Potent E'lys always rely on a very cold continent which we have not had during the E'lys of the last 5 years. I am confident the cold trend will continue to emerge and prehaps next year the real BEAST will arrive.

One of the other things this winter has not yet delivered could be coming if the models verify.... A notherly born LP with the potential to tap into even colder air.....Interesting times ahead.... I recall some of these in the 80s with huge unforecast snowfalls.

But I am still to witness a POLAR LOW. Can anyone post a chart of a classic?

[cold snap]

GFS 18Z is a bitter run if you live in the atlantic becuase that where the cold artic air is going

[nick sussex]

Interesting UKMO fax charts for 96 and 120 hrs, its funny if you looked at the 120hrs without seeing any other output and asked what happens next you'd be pushed to come up with anything but a cold outlook.

But the models have other ideas allegedly! Maybe we can order an extra supply of reverse zonal winds to send that low even further sw!

[Cumulonimbus Tower]

GFS 18Z is a bitter run if you live in the atlantic becuase that where the cold artic air is going

GFS is following the ECM of earlier, bringing colder air in from the north (West/East) before this time next week and also setting up a cut off low towards the mid atlantic. For all of you with model fatigue out there, i think we are uncovering the next part of the plot

Not exactly the same by 180 admittedly, but hey....

[mountain shadow]

GFS 18Z is a bitter run if you live in the atlantic becuase that where the cold artic air is going

That has been the case for the last 48 hours, however signs that the snow risk will increase as the week progresses as we tap into that very air as the trough looks like pulling into the continent.

Very strange movement of the trough and I'm not understanding whats steering it.

[Bolton67]

It has seemed like an eternity as we watched Snowmaggedon Easterlies gradually evaporate to a short blast into France. Then we consoled ourselves with a real Northerly Arctic blast in the offing; this will now try to warm the Central Atlantic. We now face a messy & marginal Limbo.

But ECM still says real cold is just "yet another week away". It's always a week away.

I, for one, don't believe it.

Time to call it quits i think len!!

Nobody can complain about this winter..

But once again we are looking at chasing the cold...but the cold is not chasing us.

March will soon be upon us...Sun will be higher and a little more powerful. still, we still could see some wintry weather , but gone are the days of December and January.

[cold snap]

Interesting UKMO fax charts for 96 and 120 hrs, its funny if you looked at the 120hrs without seeing any other output and asked what happens next you'd be pushed to come up with anything but a cold outlook.

But the models have other ideas allegedly! Maybe we can order an extra supply of reverse zonal winds to send that low even further sw!

I sure Nick they are out to confuse us GFS 18Z comes out With the UK fax Charts.

To different outcomes nearly everytime.

Model fatigue is now seting in.

[mountain shadow]

Time to call it quits i think len!!

Nobody can complain about this winter..

But once again we are looking at chasing the cold...but the cold is not chasing us.

March will soon be upon us...Sun will be higher and a little more powerful. still, we still could see some wintry weather , but gone are the days of December and January.

Don't count your chickens yet, the trend is colder as the week progresses.

[cooling climate]

Interesting UKMO fax charts for 96 and 120 hrs, its funny if you looked at the 120hrs without seeing any other output and asked what happens next you'd be pushed to come up with anything but a cold outlook.

But the models have other ideas allegedly! Maybe we can order an extra supply of reverse zonal winds to send that low even further sw!

Looking at the t120 FAX chart I would think the only direction the low would be going is east, southeast.

The GFS 18s looks wrong to me,totally implausible.

Lets see what tomorrows runs bring.

[ribster]

Time to call it quits i think len!!

Nobody can complain about this winter..

But once again we are looking at chasing the cold...but the cold is not chasing us.

March will soon be upon us...Sun will be higher and a little more powerful. still, we still could see some wintry weather , but gone are the days of December and January.

I think all that view the model thread are abundantly aware that winter runs from 1st December to 28th Feb, I keep hearing we are running out of time, well yes, winter ends in two weeks - nothing new there. I think we could see some fun and games yet, but yes, the sun is getting higher in the sky and stronger, it's the inevitable changing of the seasons, another year older etc etc.

[Cumulonimbus Tower]

Time to call it quits i think len!!

Nobody can complain about this winter..

But once again we are looking at chasing the cold...but the cold is not chasing us.

March will soon be upon us...Sun will be higher and a little more powerful. still, we still could see some wintry weather , but gone are the days of December and January.

Looking at the models we still have a period of uncertainty to contend with... (brings out the chocolate and cookies) Oh my god, i think i'm turning into....

The models are starting to show the possibility of further cold outbrakes towards the end of next week and i for one do not think that mid feb is the end of winter....

[kent]

The ECM was a good run because it gave hope. The GFS is wrong because it removes hope. People are seeing what they want to believe, surely this is proof that these models dont work. The only true forecast is the one on your doorstep.

[Guest North Sea Snow Convection]

The ECM was a good run because it gave hope. The GFS is wrong because it removes hope. People are seeing what they want to believe, surely this is proof that these models dont work. The only true forecast is the one on your doorstep.

True! And it's snowing again!

The ECM tonight is the next piece of the jigsaw - the control member is the band piper!

Night all!

[Rollo]

Looking at the models we still have a period of uncertainty to contend with... (brings out the chocolate and cookies) Oh my god, i think i'm turning into....

The models are starting to show the possibility of further cold outbrakes towards the end of next week and i for one do not think that mid feb is the end of winter....

Harking back to winters of old,come mid-feb there was plenty of time for further quite intense cold,bearing in mind all the outside factors I feel we could still experience a pretty cold snowy spell but hey lets not be greedy as most of us have done pretty well for snow and cold thus far.

[January Snowstorm]

Very subtle trends on the 18z and ECM of an upgrading of both the short and medium term

Next week's low has potential to deliver surprise snowfall in many areas as the uppers quite regularly hover at -5.

Also a trend developing of an Easterly setting in behind the low.

As Nick said earlier it's now or never & there's a small but growing chance it could be now

[Liam J]

winter does end in 2 weeks in the world of weather, however remains winter until the clocks move forward, but by no means does it mean the end of winter type weather as many years can prove during march and april can produce heavy snowfall march in particular can be snowier for some areas.

the big difference is the sun strength which modifies any cold air mass through the day with surface heating, so you may get to 6c in and arctic air mass in march sun but when a snow shower comes along the temp plummets.

you may think its not worth it but ive been looking at the cfs long range model and march has been looking very cold and below average.

[Thundery wintry showers]

I mentioned that the models weren't supporting the possibility of the low drifting to the SE, but that's no longer true as the ECM shows exactly why that would be the best option for those after another widespread snowy spell. A cold easterly backing north-easterly and then northerly as the low retreats eastwards.

GFS 18Z however looks like it keeps the low on top of Britain and the precipitation charts indicate a slow-moving frontal system trapped within the low and keeping it dull and wet rather than bright and showery- always a possibility in a slack cyclonic sort of setup.

[nick sussex]

Very subtle trends on the 18z and ECM of an upgrading of both the short and medium term

Next week's low has potential to deliver surprise snowfall in many areas as the uppers quite regularly hover at -5.

Also a trend developing of an Easterly setting in behind the low.

As Nick said earlier it's now or never & there's a small but growing chance it could be now

Yes given the set up and the very cold air about to drop into western Russia in conjunction with the PV being displaced by the current stratospheric warming then this is the final chance to see a freeze. Of course I'm not saying theres no further snow chances as we head into March, that can be a snowy month but what i'm talking about is the chance for seeing very cold daytime temps with snow that lasts and doesn't turn into a slushy mess by midday.

Of course the models may well just decide to go with the slow painful lifting out of the cold as the low just sits over the UK, theres no guarantees any of that very cold air to the east will get far enough west but looking at the overall model output theres enough there to hold out some hope that we may see one final very cold spell.

[damianslaw]

Yes given the set up and the very cold air about to drop into western Russia in conjunction with the PV being displaced by the current stratospheric warming then this is the final chance to see a freeze. Of course I'm not saying theres no further snow chances as we head into March, that can be a snowy month but what i'm talking about is the chance for seeing very cold daytime temps with snow that lasts and doesn't turn into a slushy mess by midday.

Of course the models may well just decide to go with the slow painful lifting out of the cold as the low just sits over the UK, theres no guarantees any of that very cold air to the east will get far enough west but looking at the overall model output theres enough there to hold out some hope that we may see one final very cold spell.

Eeven if the low just sits over us, it will eventually fizzle out in situ, there is nothing chasing it from the atlantic, an attack from the NE is likely eventual outcome or indeed a southerly tracking low will appear in its place, either way the longer term outlook is looking a cold one from the north east.

Its interesting how the gfs has switched from yesterday in its tracking of the low, whereas ECM and UKMO have been less erratic, could this be yet another case of the gfs having orginally got the right trend only mid period to change its ming and then once again revert back to what it originally thouhgt, watch GFS as it seems to always be doing fall in line with ECM and pull this low eventually south east - it seems this is the only place for it to eventually go..

[nick sussex]

Eeven if the low just sits over us, it will eventually fizzle out in situ, there is nothing chasing it from the atlantic, an attack from the NE is likely eventual outcome or indeed a southerly tracking low will appear in its place, either way the longer term outlook is looking a cold one from the north east.

Its interesting how the gfs has switched from yesterday in its tracking of the low, whereas ECM and UKMO have been less erratic, could this be yet another case of the gfs having orginally got the right trend only mid period to change its ming and then once again revert back to what it originally thouhgt, watch GFS as it seems to always be doing fall in line with ECM and pull this low eventually south east - it seems this is the only place for it to eventually go..

I think we do actually need another shortwave to develop and run ese to help pivot the low and at the same time absorb it and thats what the ECM wants to do this then makes the low further south the main feature,then when this begins to track ne it does so more favourably further se and allows the ridge to build over the top.

Overall the UKMO looks to have called the set up more accurately as the models have backed the pattern west and with it that early low that drops south.

[snowray]

Interesting UKMO fax charts for 96 and 120 hrs, its funny if you looked at the 120hrs without seeing any other output and asked what happens next you'd be pushed to come up with anything but a cold outlook.

But the models have other ideas allegedly! Maybe we can order an extra supply of reverse zonal winds to send that low even further sw!

I'm just loving the Fax charts.

I wonder if UKMO has got it right this time? ECM has moved in the right direction big time, GFS is slowly but surely shifting as well. We will know more undoubtedly by the morning.

[kumquat]

Re 18z GFS: Being a complete noob, but trying to learn the evolution, am I right in saying that the low that is giving the grief is born out of the warm air advection in the Atlantic building towards the Canadian HP and being deflected East because it gets squeezed between this and height rises over Greenland. The strong Scandi low combined with flabby HP over the UK then means it gets pinballed down over us?

hey - i tried

Edit: I see things have moved on a lot with regards to the ECM 12z output and also the UKMO

Much more encouraging after a deflated Friday afternoon at work.

[dewei]

ECMWF still isolated this morning with the low going well south of the UK. GFS, UKMO, NOGAPS, GME, GEM all in close agreement in having the low turning and festering over the BI!

[winterof79]

Re 18z GFS: Being a complete noob, but trying to learn the evolution, am I right in saying that the low that is giving the grief is born out of the warm air advection in the Atlantic building towards the Canadian HP and being deflected East because it gets squeezed between this and height rises over Greenland. The strong Scandi low combined with flabby HP over the UK then means it gets pinballed down over us?

hey - i tried

Edit: I see things have moved on a lot with regards to the ECM 12z output and also the UKMO

Much more encouraging after a deflated Friday afternoon at work.

Just had a peek at 00z GFS,shows a snow event Tuesday morning and Thursday morning if i see it correctly.528 dam line across a good portion of the UK most of the week.Precipitation heavy also.Another very interesting week in a very interesting winter...so far

[bluearmy]

another interesting set of runs from the 00z's.

i wouldnt say that any model has a decent hold on the med term. faxwise, the snow potential for tues is slightly downgraded on the T84 compared to the T96 due to the angle of approach of the fronts being more nw/se than w/e. however, what should be noted is the sqeeze of pressure to the se T72 which holds up its progress and could well spring a surprise or two.

ecm is good in that it continues yesterdays 12z idea of dragging the cold air in from the ne by droping the shortwave further south. the neg zonal flow takes energy into the atlantic which prevents the ne flow we saw on yesterdays 12z. however, cold uppers are dragged into the general flow over us and there are snow opportunities aplenty on that run T144 and beyond. for scotland, it stays cold pretty well throughout.

would like to see UKMO T144 looking to take the trough further south on the 12z run.

GFS fi makes me chuckle as usual.