Model Output Discussion 4th Dec.2013-12z onwards.

[Catacol]

Good grief! that looks hideous...

 

 

RJS gets it right again at 2 months range. Astonishing - at least: if it turns out that way it will be.

[legritter]

Any cooler/colder incursions no doubt much dependent on final track of LP systems expected in the run up to the festive period. The devil of course very much remains in the detail, although a rather punchy NW Pm type airstream can and usually does throw absolutely anything at us, bar the kitchen sink

there was a kitchen sink picked up by the gales back in the late 80s ,in someones back yard it was awaiting fixing by plumbers ,so going by current models westerly theme up till christmas with some colder uppers possible ,i think beyond 10 days could be a tricky one to forecast .

[Summer Sun]

RJS gets it right again at 2 months range. Astonishing - at least: if it turns out that way it will be.

 

Indeed this is what he wrote for those who have not read his LRF yet

 

I'm expecting some rather lengthy intervals of very mild southwest flow and occasional heavy rainfalls and strong winds during much of December, late January and possibly into part of February although here I expect any mild spells to be more caused by southerly flow associated with European blocking. March by contrast may be dominated more by cold zonal flow patterns.

 

His Christmas predictions may be out (more so the temperature) be as ever time will tell

 

Meanwhile the chances of a white Christmas seem rather low from this perspective, with a peak in temperatures right on the 25th in the research output, in fact Christmas Day is indicated as having the best chance of all dates this winter to set a record high temperature which would be 14 to 17 C in most regions. Not saying it will necessarily be that mild but above 12 would not surprise me at all given the strength of this mild signal (which then fades away rapidly by New Years).

[NorthernRab]

Some fantastic input in there as mentioned   and yes, today's windstorm looks to be the first of many to effect the North and Outer Isles over the coming days. 

 

Where are the North Isles and the Outer Isles, GTLTW? I assume you mean the Northern and Western? 

[gottolovethisweather]

Where are the North Isles and the Outer Isles, GTLTW? I assume you mean the Northern and Western? 

 

Being a Sarf England resident, my geographical knowledge becomes quite poor North of Watford.

 

For the benefit of others, best go by Rabs description of those Northern parts who should be battening down the hatches as I speak, a lot of rainfall to boot as clearly indicated by the current radar.

Edited December 14, 2013 by gottolovethisweather

[weatherguy]

GFS once again going for this interesting feature cropping up around Christmas time:

 

 

Very marginal, but a potential rain-snow event as the low moves north east:

 

 

As I say, very marginal, and silly to back it at this range, but something to keep an eye on given that it keeps being modelled

Edited December 14, 2013 by weatherguy

[ICETAB]

Indeed this is what he wrote for those who have not read his LRF yet

 

I'm expecting some rather lengthy intervals of very mild southwest flow and occasional heavy rainfalls and strong winds during much of December, late January and possibly into part of February although here I expect any mild spells to be more caused by southerly flow associated with European blocking. March by contrast may be dominated more by cold zonal flow patterns.

 

His Christmas predictions may be out (more so the temperature) be as ever time will tell

 

Meanwhile the chances of a white Christmas seem rather low from this perspective, with a peak in temperatures right on the 25th in the research output, in fact Christmas Day is indicated as having the best chance of all dates this winter to set a record high temperature which would be 14 to 17 C in most regions. Not saying it will necessarily be that mild but above 12 would not surprise me at all given the strength of this mild signal (which then fades away rapidly by New Years).

Christmas is currently looking like having below average temperatures with winds coming from the north west? I find your post a little misleading...

[Mapantz]

Christmas is currently looking like having below average temperatures with winds coming from the north west? I find your post a little misleading...

If you read the first line, you'll see that it was someone else's post.The latest GFS run shows winds are actually coming from the south/south east on Xmas day but as it is in the low resolution part of the models, it's too far out for any details.

[Captain Shortwave]

Christmas is currently looking like having below average temperatures with winds coming from the north west? I find your post a little misleading...

Many issues I have with this post.

1) the post you quoted was quoting a part of Roger J Smith's forecast.

2) The metoffice update disagrees with your statement

UK Outlook for Thursday 19 Dec 2013 to Saturday 28 Dec 2013:

It is likely to remain windy and generally unsettled across much of the UK, especially in the north and west, where there will be a continuing risk of heavy rain and severe gales. Some drier and brighter interludes are also likely, particularly across southern and eastern parts. Generally mild although some wintry showers are possible in the northwest at times, and there will be some overnight frosts. Into the following week, there is still likely to be the risk of severe gales and heavy rain, mainly in the northwest. It should still be mild at times, however there will be temporary spells of cooler than average conditions, bringing a risk of patchy frost and snow over higher ground in the north.

3.

GFS mean

Looks pretty wet and average

GEM mean

Winds are more south west than north west I'm afraid.

 

I am a coldie during the winter, but I am fed up of people being labelled as wind up merchants or trolls just because they post what the charts are saying in the situation where they don't favour and winter wonderland scenario. It doesn't mean that we will see an average/mild and wet Christmas, just that the odds are more in favour of that as opposed to other scenarios. 

 

Right now washing myself down after posting deep FI mean charts

 

UKMO still looks on it own with it's version of day 5/6, which of course offers much more hope as opposed to the other models. I for one hope the UKMO is right and we might be able to stop the usual train of low pressure systems from taking their standard track just north of the UK into northern Scandinavia, and are diverted more through the UK and into central Europe.

Edited December 14, 2013 by Captain shortwave

[Frosty.]

There continues to be a good chance of the weather being cold enough for snow on christmas day and through towards the new year, especially in the north, there is also the chance of very stormy weather during the same period and speaking of disturbed weather, the next 7-10 days continue to look very unsettled with very wet and windy spells sweeping in off the atlantic, the combination of high pressure to the south, low pressure to the north west and very cold air moving out of North America is the cause of the very unsettled spell. The very cold air spilling out of the eastern US is helping to fire up the jet stream and there is currently no end in sight. The GEFS 06z mean shows a weak pressure rise to the south east of the uk at T+168 hours which may bring some respite to the southeastern corner of the uk during next weekend but persistent low heights to the northwest are likely to keep most of the uk locked into a very disturbed pattern and occasionally cold enough for wintry ppn, especially on northern hills & mountains, after that brief ridge to the southeast is pushed away, the low pressure domination intensifies on the mean from T+240 until the end of the run with a broadly westerly flow and within that flow there are likely to be colder incursions blasting across the uk as the jet digs further south.

[MR EXTREMES]

every model suggests cold enough for snow in the nw but nothing cold through December likely anywhere else although some very stormy weather is certain in places gusty at times else where.

im a coldie and would be very happy to ramp about cold if it was there but nothing in the models suggest this no northern blocking no mlb either.

 

vortex holding firm at this time so we can write of December 2013 as typicall average perhaps slightly above in the south.

 

roll on jan not that I hold much hope for jan.

[MR EXTREMES]

but saying this the vortex on the gfs at t78 is pretty much at the bottom tip of Greenland now can this vortex send a spawned low pressure se would this aid in futher developments with heights into scandi one to watch just maybe.

[Catacol]

Indeed this is what he wrote for those who have not read his LRF yet

 

I'm expecting some rather lengthy intervals of very mild southwest flow and occasional heavy rainfalls and strong winds during much of December, late January and possibly into part of February although here I expect any mild spells to be more caused by southerly flow associated with European blocking. March by contrast may be dominated more by cold zonal flow patterns.

 

His Christmas predictions may be out (more so the temperature) be as ever time will tell

 

 

Actually he was a bit more specific than the passage you quote, and if mods will permit this non-model post this is what he actually said 2 months in advance - and accurate not for the first time.

 

"Note that this pattern places ridges near 110 W and 55 W which if you do the math places the next downstream ridge close to the Greenwich meridian. That would suggest a Bartlett or Euro-high pattern but with such an active jet stream expected it's more likely to become a fast stormy flow, so I have added the detail that at least one major windstorm is probable this winter. As readers of my forecasts know, I tend to favour northern maximum around full moon in Dec (16-17) and Jan (15-16) for wind storm potential with new moon a secondary peak. However, the new moon of 1 January is well timed to coincide with a circulation change and so that could turn out to be the stage for the strongest windstorm potential. The following new moon event on 30-31 Jan is also well timed from the trend in the model output."

 

So Dec 16/17 was picked out at long range in the midst of a euro high setup.

 

I am struggling to understand Roger's methods - but he trumps the models at 2 months range or more on many an occasion.

 

Look out for another storm at NY, a colder spell on the horizon by 6 Jan and the storm possibility on 15/16 Jan when the time comes. Worth a discussion all of its own if he pulls off another forecasting coup this year.

Edited December 14, 2013 by Catacol_Highlander

[MR EXTREMES]

am I right in saying that at t108 on the gfs that is a piece of vortex at the tip of Scotland ?

[MR EXTREMES]

certainly would not be mild on if the gfs is correct so I stand corrected.

[IDO]

I was of the impression that the UKMO had backed off this morning.

 

Last night:

 

I could see where the energy was going and there was potential.

 

This morning: 

 

It looked like some of the energy was going over the top and thus flatten any heights in the NE.

 

We will see in a the 12z soon so maybe it came reverse this. 

[MR EXTREMES]

oh no the azores high is back not good  

[Cheshire Freeze]

oh no the azores high is back not good  

 

Better polar profile at 144 hrs though. Better heights in general.

[radiohead]

Like this morning's ECM, the GFS is now showing potential stormy conditions on Wednesday for NI and western Scotland.

 

 

NAVGEM :

 

Edited December 14, 2013 by radiohead

[Cloud 10]

The UKMO now has the LP at 96 hrs.

 

http://www.meteociel.fr/ukmo/runs/2013121412/UW96-21.GIF?14-17

[TSNWK]

12z. Well you to say that GFS keeps going with this theme of dropping the vortex over the North Atlantic and towards us during chritsmas week and beyond.. Ukmet stuck on 96 ?

[Iceberg]

Not much discussion yet on that GFS 12z run.....

 

Looks a corker to me, rapid PV movement, cold, with snow shower at times for the north. Major storm for the 19th for midlands northwards (something scarily the models are starting to firm up on). Then from Boxing Day onwards the UK is blasted with Major Storms, Massive winds and enough rain to p1ss even the ducks off (those that havent been eaten over Christmas). There certainly wouldn't be a long Christmas for the forecasters or emergency services if that comes off. Strangely though even with it being in the extended timeframe its all to probably with the amount of energy and location of the PV fragments.

[karyo]

The main positive I can find in the 12z GFS is that the stratosphere is showing the signs of a significant warming at the 30hpa level towards the end of the run. The first time this season that a bit of orange appears over East Asia.

 

Let's hope this is not a false dawn and that the following runs will continue with this warming.

 

Karyo. 

[Mucka]

I wonder if the MetO run will update past T96 before the New Year?

[tinybill]

Not much discussion yet on that GFS 12z run.....

 

Looks a corker to me, rapid PV movement, cold, with snow shower at times for the north. Major storm for the 19th for midlands northwards (something scarily the models are starting to firm up on). Then from Boxing Day onwards the UK is blasted with Major Storms, Massive winds and enough rain to p1ss even the ducks off (those that havent been eaten over Christmas). There certainly wouldn't be a long Christmas for the forecasters or emergency services if that comes off. Strangely though even with it being in the extended timeframe its all to probably with the amount of energy and location of the PV fragments.

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=2&ech=204

 

looking at that  at  the moment its  gone  mild  again""" with  rain!!!