Model Output Discussion

[Southender]

So Saturday seems to be the key day for most of the U.K.

Will the HP bugger off towards Greenland is the question.

The 6z shows it doing so. With an Artic blast for Valentines day?...

Edited February 9, 2010 by LeighShrimper

[Lewis]

I must admit though, i have seen huge differences/changes in the short term when there's not much agreement of course, but with such good agreement between the euros and of course the GFS i thought it was very unlikely to see such changes in such reliable time frame.

It shows a huge upgrade, although now the easterly seems to be very progressive. It also looks very messy friday onwards into Saturday. I would like to see the ensembles first, short term good, friday afterwards is of course up in the air.

I think saturday is the most important day to concentrate on. The HP is key to where our weather comes from t92-t144 onwards.

lewis

Edited February 9, 2010 by Storm Force Lewis

[TEITS]

So Saturday seems to be the key day for most of the U.K.

Will the HP bugger off towards Greenland is the question.

The 6z shows it doing so. With an Artic blast for Valentines day?...

I feel the Greenland HP is pretty much nailed. What happens afterwards is uncertain.

From a selfish point of view I would ideally prefer the pattern to be further E with NE,lys via the Greenland HP with the LP much further E. This is a much safer option plus the colder spell would be more prolonged.

I keep thinking to myself that when the models suggest a N,ly at +144 they have this centred across the UK. However as this moves into +72 the N,ly tend to back E and hit Holland instead. Ideally I would like to see this trend this time because we would have bitter NE,lys instead of a LP system!

[Iceberg]

The 138 chart on the GFS 06Z ops is a very welcome site, the ridge stays in place for longer, keeping the northern, more as a northerly and preventing the cold air from blasting out too far west, much better sign.

[Lewis]

Here she comes!

[Iceberg]

The 12Z's will be most interesting today I think.

[Lewis]

The 12Z's will be most interesting today I think.

i agree mate.

When do the fax charts (ukmo) update again mate.

[TEITS]

Well it certainly won't be mild!

http://www.wetterzentrale.de/pics/Rtavn17417.png

A fasinating spell of model watching to come I feel. An absolute nightmare to forecast and im not convinced any of the models have this correct just yet. Im even dubious of the ECM/UKMO especially as we're supposed to be experiencing mild S,lys with temps of 16C today!!

Lewis the fax charts upto +72 will update between 17.00-1830 tonight. The +96/+120 between 21.30-22.30.

Edited February 9, 2010 by THE EYE IN THE SKY

[Iceberg]

Not sure tbh, should be around lunchtime.

Very good NAE 06Z, showing light snow down the spine of the country and upto the Welsh borders, tomorrow lunchtime.

[Weather-history]

Just a quick word about some of the comments saying the E,lys have been disappointing and the best snow events have come from the N. Im surprised some are making such sweeping statements like this. This all depends on your location because for me my best snowfall has come from the E and this also applies for my broher in Northumberland who has seen alot of snow from convection. Just remember your snowfalls from the N might not have occured if the intial cold from the E hadn't moved W. For example like I say Feb 5 2009 gave me 8 inches of snow from the S but it was the intial blast from the E that allowed this to fall as snow.

It does depend on location but if you read my post I said the "most widespread snowfalls" ie the ones that affected the UK the most and they undoubtly came from the north and not the east. I don't totally agree with your assessment about the initial cold and the snowfall from the north because it is pretty irrelevant if there is a mild sector involved. Yes, if cold is present it increases your chance of snow with the initial system but the mild sector is a bigger factor and as we found that out in NW England, when we had little snow with that system that Saturday night before Christmas even though cold air was in front and behind the system.

Edited February 9, 2010 by Mr_Data

[Lewis]

Im looking forward to the fax charts, areas in the east, the GFS and UKMO have been showing a trough feature when the cold pool hits around 3am tomorrow morning. I could get some snow, and wake up to a good covering in morning, you never know

[Southender]

Great run this morning.

Hopefully 12z's will follow suit.

Very exciting times indeed.

Edited February 9, 2010 by LeighShrimper

[TEITS]

It does depend on location but if you read my post I said the "most widespread snowfalls" ie the ones that affected the UK the most and they undoubtly came from the north and not the east.

Still don't agree.

Locations that have seen their most widespread snowfall from NE/E,lys are NE Scotland/NE England/E Anglia/SE/E Midlands. The locations that are exempt from this are mainly NW/SW England/Wales who have seen frontal snowfall.

The amount of snow I have seen from the N measures 0cm so far this winter!!

[nick sussex]

I feel the Greenland HP is pretty much nailed. What happens afterwards is uncertain.

From a selfish point of view I would ideally prefer the pattern to be further E with NE,lys via the Greenland HP with the LP much further E. This is a much safer option plus the colder spell would be more prolonged.

I keep thinking to myself that when the models suggest a N,ly at +144 they have this centred across the UK. However as this moves into +72 the N,ly tend to back E and hit Holland instead. Ideally I would like to see this trend this time because we would have bitter NE,lys instead of a LP system!

Yes its a bit frustrating in that northerly topplers are often pushed east but proper Greenland highs seem to result in troughing often too far west, we certainly need the eastwards trend from the gfs 06hrs run continued with this evening,I'd also agree with Karyo earlier on, not liking that ECM run after 168hrs as it pulls everything too far west.

[Lewis]

Still don't agree.

Locations that have seen their most widespread snowfall from NE/E,lys are NE Scotland/NE England/E Anglia/SE/E Midlands. The locations that are exempt from this are mainly NW/SW England/Wales who have seen frontal snowfall.

The amount of snow I have seen from the N measures 0cm so far this winter!!

Hello

I think both of you have a good case for argument. I'll step in the middle and confirm i recieved most of my snow from the N/NNE this winter , although my heaviest accumulation did come in fact from an Easterly

[cooling climate]

The trend is certainly for things to back east over the coming days.

The residual energy(shortwave )that hangs to the west of Svalbard

could very well disappear or move south with the rest of the trough

over subsequent runs which would lead to a much colder run than is

presently being shown.

Plenty to watch over the coming days.

[Uncle_Barty]

Oh my god, after all that from me yesterday about the trend of the HP being way too far South, and it continuing to do so. It's pushed North again!! and I and other people are in the firing line now.

I cant believe it, i look like an idiot now. Maybe i need to stop been so hasty and learn how to read the blooming models better. I really am shocked, it's proved me so blooming wrong lol, 12 runs south 2 runs North. :|

And that's why I always say that nothing is ever nailed on until it arrives. There was certainly a trend to move the high south over the BI and that might yet still happen! It's all down to specifics that are chopping and changing all the time. Personally I am using the model output as a guide, together with the valuable mutterings of GP et al.

[nick sussex]

It's a shame these NAE precip forecasts change so much between runs!

http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=frfr&MODELL=nae&MODELLTYP=1&BASE=201002090600&VAR=prty&HH=48&ZOOM=0&ARCHIV=0&WMO=

Time to get the supplies in down here! What a difference from the first winter down here in 07/08, that winter I didn't see a single snow flake away from the mountains although at the time I was renting further west towards Orthez which is only 300 feet above sea level, thankfully I moved east and higher up.

It certainly looks interesting for the UK towards the end of the weekend as those fronts head south into the cold air, the GFS 06hrs run was a good start but I think another few hundred miles further east could make a huge difference to extending the cold and bringing more snow.

[mountain shadow]

Once in a generation, snowmageddon charts for the North West if the GFS 6z verifies (which it wont).

Hopefully a trend towards a more neutral based -NAO which would provide the chance for substantial snowfall in the medium term for many. Even a slightly west based -NAO would provide for here.

Strange for once that we want the medium term output to move east where in times not long gone, we would see whole lot ship east into the continent.

Exciting times ahead.

[Buzzit]

At this point I have to say I have been following the NAE and NMM and in my opinion they have been rubbish this week

Getting precipitation completely wrong even by the time the data is released. Very poor.

Goes to show how uncertain the actualities are at the moment

[bluearmy]

I note that chio on the strat thread feels that the retrogression is a tad overdone at the moment. looking at the latest NAEFS, i'd agree and say that the 06z fits in pretty well with what that shows out to day 10. although the 06z is then typically progressive, the NAEFS never really warms up out to T384 with a new omega block developing in the atlantic.

very reminiscent of december though possibly a tad further east (hopefully) to avoid the south warming up.

[karyo]

The trend is certainly for things to back east over the coming days.

The residual energy(shortwave )that hangs to the west of Svalbard

could very well disappear or move south with the rest of the trough

over subsequent runs which would lead to a much colder run than is

presently being shown.

Plenty to watch over the coming days.

Hopefully, but at the moment this trend can only be seen in the 6z gfs, not in the all important euro models!

Very interesting to watch the developments this afternoon!

Karyo

[Bobby]

Well it certainly won't be mild!

http://www.wetterzentrale.de/pics/Rtavn17417.png

Well that's wrong, it shows 0c for me but it's currently 3.1c.

Next week is looking very interesting, in fact I'm getting a feeling of Deja Vu as it's looking so similar what we've seen already this winter. It may not come off but at least it should be interesting model watching unlike this boring dry anticyclonic weather.

This looks like being a very unstable Northerly next week and if the latest GFS/ECM verified no doubt a lot of places would get pasted. There will possibly be features developing from the flow giving widespread snow also, not just the favoured places in a Northerly - remember the Jan 6th South snow event, shows what can happen in unstable Arctic flows.

Then the possibility showing of attacks from the Atlantic with potential battleground snow. Going to be interesting model watching coming up for sure.

ECM and GEM do have the outbreak too far West which is not so good, further East like the GFS is better.

Edited February 9, 2010 by Barb-

[Weathizard]

Well that's wrong, it shows 0c for me but it's currently 3.1c.

Next week is looking very interesting, in fact I'm getting a feeling of Deja Vu as it's looking so similar what we've seen already this winter. It may not come off but at least it should be interesting model watching unlike this boring dry anticyclonic weather.

This looks like being a very unstable Northerly next week and if the latest GFS/ECM verified no doubt a lot of places would get pasted. There will possibly be features developing from the flow giving widespread snow also, not just the favoured places in a Northerly - remember the Jan 6th South snow event, shows what can happen in unstable Arctic flows.

Then the possibility showing of attacks from the Atlantic with potential battleground snow. Going to be interesting model watching coming up for sure.

Its for Next week...

[Bobby]

Its for Next week..

Oops, I saw Tue and assumed it was today.

GEM and ECM do have the outbreak too far West which could be the spoileer, more east like the GFS is preferred.

Edited February 9, 2010 by Barb-