Yesterday we were talking about model resolution. Here's an example of a GFS 6z op chart plotted at 0.02deg instead of 0.25deg. The resolution is SO high that I've had to make the plot bigger and skip grid points to make it readable. Of course it all matters not a bean to the forecast accuracy and that is the point often lost on people. Factors determining that are: model input data, model physics, internal model resolution which is different thing

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That's 3 GFS parallel runs in the trot with evolution to a Scandi high in FI. Unusual consistency so far out. Looking through the ENS there does appear to be some support. It all seems to depend on the extent of the Iberian high ridging North. 

Given it's FI, all very possible that the evolution could disappear in the next run, but interesting all the same. 

 

I make it four. Such consistency across one model is normally reserved for the 3-5 day range, not 10-12. Something up, or could it just be random, like throwing four sixes with four rolls of the dice ? Even if it disappears - which is surely must do even if it turned out to be an actual evolution in 10 days time - it has to be of interest? Does the Para lose half its resolution after 192hrs as per the Op?  I had a quick look for the Para's verification stats but couldn't locate 

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Sure the parallel is an outlier but it is not a one off is it? That scenario has been shown a few times now and something similar popped up in the op yesterday.

Many times disappointed but never dismissive!

 

Yes also no -10c uppers in FI like in previous runs:

 

What is most noticeable, is have another 4 day milder (less cold, not mild) spell similar to current one, with the trend (mean) then reverting to about 4c below long term norm.

 

Whilst they may not be that interesting, there is something unusual in that we keep reverting to the bit colder than normal, nothing that could remotely be described as a warm plume.

 

What is frustrating is that for much of the country it just brings more cold rain, or sleet.  Not what most people consider as a proper winter. But a potential for a long winter (and a wet one)

 

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All eyes down for the 12z. Icon first out of the blocks and t180 as far out as the model runs, looks to be going the same way as the gfs para runs. Pressure remains high to the north with troughs disrupting west to east across the UK and very cold air to the the n/e pushing south. With cold pooling to our east.

Great start to this afternoons runs.

 

 

What is most noticeable, is have another 4 day milder (less cold, not mild) spell similar to current one, with the trend (mean) then reverting to about 4c below long term norm.

 

Whilst they may not be that interesting, there is something unusual in that we keep reverting to the bit colder than normal, nothing that could remotely be described as a warm plume.

 

What is frustrating is that for much of the country it just brings more cold rain, or sleet.  Not what most people consider as a proper winter. But a potential for a long winter (and a wet one)

 

Amazing that this winter looks like being a below average winter CET.

Does a consistantly below average winter from Dec - April be classed as a classic without a proper snowfall ?

 

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Think the Para will need to pull a rabbit out of the hat to save this one!

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Think the Para will need to pull a rabbit out of the hat to save this one!

It did find something with ears and a fluffy tail about 100hrs later😉🤡

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Think the Para will need to pull a rabbit out of the hat to save this one!

Operational has southerly tracking lows which follow the 12z Para. I wonder how this Op run will sit in the ENS!?

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Parallel goes for a northerly rather than easterly but still cold, and the GFS op run follows suit.

GEM also close to an easterly towards the end.

 

And P10 of the GEFS throws a curveball, binning the mild incursion altogether with a frigid blast from the north

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Few more ENS members flirting with a Scandi high in 11 days

Amazing that this winter looks like being a below average winter CET.

Does a consistantly below average winter from Dec - April be classed as a classic without a proper snowfall ?

 

One of the problems with the CET is in winter it favours an area of the Country that is relatively good for snowfall and frosts. We have had very few frosts and virtually no snowfall this winter. I bet my mean temp is higher than the CET.

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Short term 12z 850's down again to -6.8C mean on 25th. Snow row up to 20 (All London data)

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Trend for a renewed cooldown in early Feb is growing IMHO.

Hopefully we will start to see that come into range of the ECM within a day or two.

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One of the problems with the CET is in winter it favours an area of the Country that is relatively good for snowfall and frosts. We have had very few frosts and virtually no snowfall this winter. I bet my mean temp is higher than the CET.

Imby I'm below the CET as had quite a few days with fog or cloudy with cold rain keeping the temp low but no snow

https://www.cl.cam.ac.uk/research/dtg/weather/period-text.cgi?2021-01 

ECM looks primed for a NE /E outbreak

Fascinating ECM plenty of snow interest even for the south upto 144h . Then goes very mild.

Has snow event on Sunday  for the South and EA. Plenty of snow up north especially for Scotland.

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Mild rain or cold rain. Take your pick.

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Back to the drawing board if ECM on the right track!

Mild rain or cold rain. Take your pick.

No need to pick I'll be able to enjoy both varieties

Some interesting signals still in the longer range output and GFS still reasonably confident of a cooldown post the milder few days in the middle of the run.

GEM ended on an intriguing note with a rather amusing contrast of -10 850s from the East/North East and +10 850s (few higher splodges) coming in from the SW.

ECM is an odd run - T168 to T192 the Atlantic seems to reverse and then  T216 it wanders a LP through and in to Scandi with no issues. The T240 chart is I would say 'poised' in that it could lead to cold or very mild quite easily. 

All good fun

I think the outlook up to the 30th Jan is being modelled consistently enough to have a reasonable degree of confidence in it verifying (down south, chilly/cold for 5/6 days, then mild/very mild for 3/4 days but I'll reserve judgement on the longer term outlook for the time being. Decent chance of cold is there but some very mild stuff is possible too. I guess we might be really unlucky and be on the boundary of both airmasses and just get even more rain

 

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