Model Output Discussion

[Coast]

OK folks, you know the drill. Current Model Output Discussion here only.

Other chat, joy/despair, non current model related conversation, one-liners or comments about nothing in particular have their own threads where you can share your thoughts with others.

[TEITS]

Looking at the UKMO and I feel the only chance of a spell of snow is during Monday night into Tues. Look at the links below and note the band of snow moving SE but also note the cold pool across E Anglia/SE.

So based on what I have seen today I would say a realistic appraisal of the models is a band of rain moving SE turning to snow as it does so. Beyond this probably becoming less cold with snow being restricted to higher ground in Scotland and maybe the far N of England.

[grab my graupel]

Evening everyone, can we get back to discussing the actual model output please?

The 'Robert' related posts have been moved to here:

http://forum.netweather.tv/topic/61151-model-chat-and-moods/page__pid__1768498__st__119entry1768498

Thanks

[MKN]

Think theres a slightly pessimistic view regards to next weeks weather on here. Current charts dont quite show the blizzard we were hoping for apart from favoured areas of scotland. However for the rest of us i wouldnt be suprised to see 2/3 hours of heavy snowfall that causes problems for a short period of time in many parts of the uk. Accumulations may only be temporary but could still be quite interesting non the less. After next week things could still favour cold with all the northern blocking, so overall things arent that bad. Reading this thread without seeing the charts would have you believe we were getting atlantic storm after atlantic storm rolling in next week with temps around 12c.

[TEITS]

Think theres a slightly pessimistic view regards to next weeks weather on here.

Far better to be realistic rather than mislead members. I realise some members don't fully understand how to read models and I don't want them to believe blizzards are coming when the models don't suggest this.

As I said earlier Mon/Tues offers the best hope. See my post above and the latest fax chart.

http://www.meteociel.fr/ukmo/fax/fax72s.gif

Beyond this and the problem with the model output is the LP remains centred over the UK. Looking at the UKMO +144 and we can see bitter E,lys to the N but unless the LP moves eirher S or SE we're unlikely to pull any colder air in.

[MR EXTREMES]

Think theres a slightly pessimistic view regards to next weeks weather on here. Current charts dont quite show the blizzard we were hoping for apart from favoured areas of scotland. However for the rest of us i wouldnt be suprised to see 2/3 hours of heavy snowfall that causes problems for a short period of time in many parts of the uk. Accumulations may only be temporary but could still be quite interesting non the less. After next week things could still favour cold with all the northern blocking, so overall things arent that bad. Reading this thread without seeing the charts would have you believe we were getting atlantic storm after atlantic storm rolling in next week with temps around 12c.

it does look like the gfs was trying to swirl the cold around it but its all gone a bit pete tong if you ask me we look like its going to be middle ground situation for sometime yet it seems everything is counter acting against each other.

so if northern blocking wernt there then maybe it would have been a different outcome,

everything is pukka inregards to the teleconnections,

but not so good with system movement.

i really does go to show how much everything needs to come together perfectly for the right outcome.

i get the feeling the colder air is really trying to have ago at us but the system thats causing the problems is causing more problems futher out.

we need this low pressure to pea off or move somewhere else,

but its not likely to for sometime.

im also pretty confident that the met office will remove there advisory for us in southern england by sunday.

it should not be there perhapes rain and sleet and thats pushhing it more likely to be rain for sure,

infact the charts dont really hold much hope unless cumbria north and perhapes high ground of wales.

still its been intresting winter and very messy week of model watching and im happy the setup is here so nomore dissapointment which for me is a good thing lol.

[Secret Society]

i find it funny people still beleive in the models.

they didnt know their butt from their elbow last week for days on end.

in the end UKMO won out (with human intervention)

Edited February 12, 2010 by Secret Society

[ChartViewer]

As I said earlier Mon/Tues offers the best hope. See my post above and the latest fax chart.

http://www.meteociel.fr/ukmo/fax/fax72s.gif

Beyond this and the problem with the model output is the LP remains centred over the UK. Looking at the UKMO +144 and we can see bitter E,lys to the N but unless the LP moves eirher S or SE we're unlikely to pull any colder air in.

That Fax chart is actually nearly a very good chart. Quite frustrating when you see blocking

to our NW some blocking elsewhere and we still cannot get that LP to slip S/SE.......Very

annoying fax chart as that is not that far away from UK seeing a nice snow event

Edited February 12, 2010 by grab my graupel

[MKN]

This day brought heavy rain which unforecast at the time quickly changed to heavy snow.

The system is further east but i want to highlight the 850s. Not always the defining factor and under low pressure ive tended to find more margin of error.

[karyo]

No excitement from the 12z output so far. The ensembles show nothing mild but nothing particularly cold either! The UKMO is looking very frustrating with the low keeping the cold uppers at bay!

Let's see what the ECM will bring...

Karyo

[Cumulonimbus Tower]

No excitement from the 12z output so far. The ensembles show nothing mild but nothing particularly cold either! The UKMO is looking very frustrating with the low keeping the cold uppers at bay!

Let's see what the ECM will bring...

Karyo

NOGAPS seems to go off to somewhere interesting longer term... I'm backing the ECM to follow that

[D KARLSON]

Far better to be realistic rather than mislead members. I realise some members don't fully understand how to read models and I don't want them to believe blizzards are coming when the models don't suggest this.

As I said earlier Mon/Tues offers the best hope. See my post above and the latest fax chart.

http://www.meteociel.fr/ukmo/fax/fax72s.gif

Beyond this and the problem with the model output is the LP remains centred over the UK. Looking at the UKMO +144 and we can see bitter E,lys to the N but unless the LP moves eirher S or SE we're unlikely to pull any colder air in.

Unfortuately i think that very cold air trapped just to the north of scotland with the attendant scandi high will stay where it is, at least for the time being.

Looking at similar synoptics in the past it looks like the low willcontinue to hug the edge of the high pressure until it fills and decays and that takes us past 144 hrs ,so looking beyond that which is speculation at thios point, there maybe a window where by the high might make some progress into Scotland on the back of a northeasterly and then perhaps our next cold outbreak with lows passing across central parts of the uk.

As for Scotland its quite common for some very snowy weather in february as cold air hangs on with milder air to push up from the south, this ceratinly seems to be the case this time round and they could get a pasting up there next week

Edited February 12, 2010 by D KARLSON

[bluearmy]

The problem beyond the initial push s of the trough next week is that for most of the country it brings a sw flow. without a flow off the continent, the current models are generally showing no snow away from n england/scotland and high ground of wales/n midlands. still time for a subtle shift in the flow or a small change in the track but time running out fast for widespread lowland snow next week apart from a transient rain preceded by etc etc to begin with.

[remymartin]

The ecm is a turn up has the low much more south

[January Snowstorm]

The ecm is a turn up has the low much more south

Yes ECM is a very good run compared to the rest.

This could easily upgrade next week yet

One thing I would say about next week is that really frigid air being so close is not the norm and may have an impact

[cooling climate]

The ECM chart at t168 is a lot better with the Iberian low phasing with the low centered over

Ireland and pulling it southwards. Hopefully this is the way the models will go and pressure

then building over Scandinavia pulling in a very cold continental feed.

[damianslaw]

Don't bank on what any of the models are showing for early next week will be the end result, there is a good 48 hours still to go and as we know when unusual set ups are progged, the eventual outcome is not normally known until the actual event is upon us.

There does semm a trend to show the low filling over the country which is quite unusual for a winter low, there is some very cold air just to our north and we are also pulling in some cold from the continent as the front moves in, I think there are going to be some surprises and the forecasters are going to get caught out on this one with some localised snowfalls occuring where not expected.

What the models cannot do at this stage is forecast the intensity of the precipitation and hence add in the factor of evaporative cooling, I've seen far more marginal situations for snow deliver the goods.

Longer term if the low does pull to the south and south east then that cold to the north will quickly spill our way, the overall outlook for the foreseeable future is cold and wintry.

Edited February 12, 2010 by damianslaw

[karyo]

NOGAPS seems to go off to somewhere interesting longer term... I'm backing the ECM to follow that

Well, I am pleasantly surprised with the ECM at 144 and 168 hours! The secondary feature further south, deapens and becomes the main low. As a result the centre of the low pressure is further south at 168 hours with a much cooler easterly flow over the UK!

This should be in line with the 0z De Bilt ensembles which were chilly throughout!

Karyo

[Snowyowl9]

The ecm is a turn up has the low much more south

Very nice!

http://www.wzkarten.de/pics/Recm1681.gif

Next chart is even better.

[TEITS]

The ECM chart at t168 is a lot better with the Iberian low phasing with the low centered over

Ireland and pulling it southwards. Hopefully this is the way the models will go and pressure

then building over Scandinavia pulling in a very cold continental feed.

Yep the ECM is showing the ideal route back to cold. As you say the Iberian low pulls our LP S and merges before tracking NE.

Some of the GEFS ensembles have suggested this scenario which is why some members have dropped below -15C. Should this occur then colder upper temps won't be in short supply as its bitter to our N.

The ideal scenario is the phasing of these LPs occurs but the track of the LP is slightly further S than the 12Z ECM shows. Further S means a quicker return to bitter E,lys and trust me this would be very cold!

[Cumulonimbus Tower]

Well at least this evenings ECM and NOGAPS show that there is a cold way out of next weeks set up. Whether it is just a blip or a new trend remains to be seen.

In the later frames of the ECM it almost seems like the west based pattern has become so west base we become under the influance of the Scandi trough while the low pressure progged over us drifts out to the mid atlantic not really bothering us.... If you know what i mean....

Edited February 12, 2010 by ned

[TEITS]

Just to let you know the upper temps across the UK at +216/+240 are around -10C especially N/E areas. Over in Scandinavia they are -25C. Lets hope the models trend towards bringing that cold pool towards us.

[Cloud 10]

Indeed there is some very cold air to our NE in the late stages of the ecm 12z and we manage to tap into it on this run although obviously a long way out at +216hrs.

[Frosty.]

ECM 12z turns into a very wintry run, especially the second half of it with ENE'ly winds pulling down across the uk with snow showers and sharp frosts but initially next week looks like becoming very unsettled with spells of rain, sleet and snow, the snow most likely on hills and in the north but hopefully a colder trend for all. The gfs 12z op run was a bit disappointing with rain and sleet rather than snow.

[Duane S.]

I don't want this to sound like hopecasting but I really think the ECM is more on the button than the rest tonight.

With the Jetstream sat at so low a latitude and with no heights underneath us to speak of I just can't see a low pressure loitering around us for as long as some models would have us believe. Surely the logical outcome would be to merge in with the Iberian low pressure as per the ECM?