Model Output Discussion

[cooling climate]

The paralle run shows what I was referring to in my last post and a very very cold

prospect ensues for the Europe and the UK.

I think most cold and snow lovers would be happy with that outcome.

The trend to cold is growing.

[snowfish]

The 06z is the most plausible operational run I have seen in the last 3 days.

It is a good demonstration of how many cold solutions in FI have gone the way of the pear.

Have to agree with you there.....At least an end to the deluge of rain, with any luck.....Still time for a Christmas Wintery scene - Let's keep our fingers and toes crossed! lol!

[Frosty.]

The paralle run shows what I was referring to in my last post and a very very cold

prospect ensues for the Europe and the UK.

I think most cold and snow lovers would be happy with that outcome.

The trend to cold is growing.

I admire your optimism but the only trend I can see at the moment is for average or mild.

[cooling climate]

[Weather-history]

I admire your optimism but the only trend I can see at the moment is for average or mild.

Actually there is another trend, a trend for higher pressures.

[Duane S.]

Thanks for saving me the bother of looking then. I missed the 18z run but understand it was a good one for coldies, how often does the following run bring things down crashing and burning.

I saved a couple of them

[Cal]

Seems the Parallel run is the cherry pick of this mornings F.I. output, not surprisingly

http://91.121.94.83/modeles/gfsp/run/gfsnh-0-372.png?6

http://91.121.94.83/modeles/gfsp/run/gfs-1-372.png?6 -18* Isotherm on the coast of Norfolk in a near gale easterly :lol: :lol: .

Hopefully we will have some settled weather in the not too distant future .

[Radiating Dendrite]

I saved a couple of them

We all know what you will be doing later then

I have to admit the 06z was a let down......but every run is going to throw up different solutions in FI. In the reliable, the same trends were still there though.

[snowmadchrisuk]

Seems the Parallel run is the cherry pick of this mornings F.I. output, not surprisingly

http://91.121.94.83/modeles/gfsp/run/gfsnh-0-372.png?6

http://91.121.94.83/modeles/gfsp/run/gfs-1-372.png?6 -18* Isotherm on the coast of Norfolk in a near gale easterly :lol: :lol: .

Hopefully we will have some settled weather in the not too distant future .

I think I am correct in saying the parallel run has done very well this year , and has been far out preforming the GFS Operational when it comes to verification on what actually happens , at least in the +240 stage. It stuck to the constant low pressure over the uk and was right.

[Frosty.]

I saved a couple of them

Thanks, that cheered me up

It's just a case of wait and see, there is growing support now for a settled spell beginning in around a week or so from the south but the big question will be where will the high go then, how will it orientate, will it sink etc. the 6z op run is thoroughly depressing but I realise there are colder solutions, will we be lucky enough to get one of them though.

[Radiating Dendrite]

Seems the Parallel run is the cherry pick of this mornings F.I. output, not surprisingly

http://91.121.94.83/...snh-0-372.png?6

http://91.121.94.83/...gfs-1-372.png?6 -18* Isotherm on the coast of Norfolk in a near gale easterly .

Hopefully we will have some settled weather in the not too distant future .

I think that run should come with a thermal underwear warning!

It clearly highlights the different possibilities that could occur though!

[Iceberg]

The alternative 06Z is a fantastic run, and the two outcome scenario's of either very mild or very cold are still in play and will continue in play until the begining of next week IMO.

These two extremes are very much in line with the split PV and Jet positionings.

You have to favour the warm scenario, but cannot discount the colder one, except the one given by the alternative which tbh is too good to be true and would be 1 in 20 year event.

[Cecil Hogmanay Melchett]

The trend to HP is now beginning to interest me.

While its beginning to look like any HP is going be centred over Europe i actually suspect we may see some inversion cold as we head past mid month.Another intersting angle is the potential for cold air flooding down the eastern flank of the high,IF we get a south

easterly flow off the continent it could end up getting quite cold!IMO its the best option on the table,we can talk until we are blue

in the face about scandy highs and greenland highs but its all FI and with the jet as it is,i just cant see it happening.

As i have said,my expectations are very low this year so just a let up in the wind and rain will do me fine.Anything else would be

a most unexpected bonus.

06z is whatid expect given the jet,and i'd take it right now.

[snowmadchrisuk]

The alternative 06Z is a fantastic run, and the two outcome scenario's of either very mild or very cold are still in play and will continue in play until the begining of next week IMO.

These two extremes are very much in line with the split PV and Jet positionings.

You have to favour the warm scenario, but cannot discount the colder one, except the one given by the alternative which tbh is too good to be true and would be 1 in 20 year event.

We had a 1 in 20 year event last year , Well all the news story's said it was the worse snowfall Since 1991 for the South.

Edited December 4, 2009 by snowmadchrisuk

[Frosty.]

Actually there is another trend, a trend for higher pressures.

Yes there is.....and as others have already said, the 6z parallel run is a bit cold

Edited December 4, 2009 by Frosty039

[Radiating Dendrite]

We had a 1 in 20 year event last year , Well all the news story's said it was the worse snowfall Since 1991 for the South.

The Easterly shown on the parallel run would be a million times better than the one last year, which had certain flaws.

[smich]

Seems the Parallel run is the cherry pick of this mornings F.I. output, not surprisingly

http://91.121.94.83/...snh-0-372.png?6

http://91.121.94.83/...gfs-1-372.png?6 -18* Isotherm on the coast of Norfolk in a near gale easterly .

Hopefully we will have some settled weather in the not too distant future .

That first pic you've put there Cal, shows Steve Murr's favourite -

The Heart Shaped High

Smich

[kold weather]

Looks to me like the models are already reducing the chances of a cold inversion with this high, the mornings runs have shunted the high just a little further east again which then leaves us in a milder southerly flow rather then a colder flow just off the continent. The general set-up needs us to get rid of the Atlantic trough, as long as it sticks there then we will not get any sort of 'proper' cold flow...full stop, best we could really hope for is a cold inversion high.

[Guest North Sea Snow Convection]

Theres a bit of irony here. You reply to Nick who suggests theres a lot of imagination is involved in some posts and then bring out a chart from the FI-end of the GEM (a not particularly reliable model anyway) suggesting how it 'could' proceed to a cold spell. Problem is that model goes out to T+240 and it leads to... mild southerlies:

http://www.wzkarten....cs/Rgem1921.gif

And T+240 is no better either:

http://www.wzkarten....cs/Rgem2401.gif

As it stands its safe to say theres nothing in the next 7 days that will bring anything even remotely wintry. The annual chase for the carrot on a stick has begun it seems. FI will always be dominated by chaos theory, even in the mildest winters there will always be T+300 easterlies. Its sometimes good to be positive, but you might as well say every chart could lead to a cold spell if you go this route.

That chart from the t168 GEM is actually quite representative of the likely pattern by then. If you were to take into account the background factors and the suggested split in the vortex and -AO then you can see how a colder scenario could emerge. Perhaps you are not doing that and just see it from the usual warming persistence factor pespective that overules every synoptic set up irrespective of the suggestions that the individual background factors and indicators might have?

TEITS amongst others is looking at the actual pattern without being overly focused on any global warming issues and post 1987 UK winter mishaps. The models are influenced by these background factors and telecommunications etc so discussion relating to those is entirely pertinent - irrespective of the eventual outcome, cold or mild.

Edited December 4, 2009 by North Sea Snow Convection

[snowmadchrisuk]

The Easterly shown on the parallel run would be a million times better than the one last year, which had certain flaws.

I Agree In terms of how cold , But we had 12 days of non stop falling snow in Leicestershire , and IMO that will take a hell of a lot of beating. Even the met Office admit we will have periods of cold and snow this year , but the beauty of the snowfall last year was caused by warmer Atlantic air bumping into the cold air over the uk.

As I thought the Gfs Operational was one of the warmest in the ensembles with the trend to colder resuming.

Edited December 4, 2009 by snowmadchrisuk

[karyo]

The 6z ensembles: http://www.netweather.tv/index.cgi?action=ensviewer;sess=

A number of cold solutions after the 15th with a mouth watering control run!

I am mainly concentrating on the possibility of high pressure taking over and possibly give us some inversions. The operational though is sometyhing we don't want to see: the pressure

sitting to our south/southeast with a mild Atlantic feed for the UK.

Karyo

[Radiating Dendrite]

I Agree In terms of how cold , But we had 12 days of non stop falling snow in Leicestershire , and IMO that will take a hell of a lot of beating. Even the met Office admit we will have periods of cold and snow this year , but the beauty of the snowfall last year was caused by warmer Atlantic air bumping into the cold air over the uk.

But a lot of areas did not see that and were stuck in the warm sectors of the lows that caused the snow further north. The Easterly shown on the parallel would bring lots and lots of snow for nearly everyone.......especially with the North sea still being relatively warm.

[Weather-history]

Here's the mean 500hpa chart at 156hrs and it looks distinctly Bartlett

http://91.121.94.83/modeles/gens/run/gens-21-1-162.png?6

The control run has an easterly as well in FI but not as potent as the parallel run.

http://91.121.94.83/modeles/gens/run/gens-0-1-336.png?6

[kold weather]

Saying that Karyo temps stil lwouldn't be that far from average on the 06z op, and would only need a small shift westwards again to be cold, however I think its hard to ignore the 0z eCM and the GFS both shifting the intial high a little too the east again, its a trend I'm already noting this winter...one of under-estimating the jet, esp outside of 144hrs.

[mountain shadow]

The Ops and Control start to diverge a week today, anything past that date can be ignored.

When you see such differences in the model output I tend to ignore it and listen to the likes of Glacier Point and John Holmes. From what GP was saying earlier, their is nothing in the GWO to show the atlantic trough moving away, and as such a mild wet pattern is likely to continue for at least a further two weeks in my opinion.