No. You are totally misreading the synoptics. The cold air is in place over England but warmer air is aloft from the Atlantic. This mixes out the cold layers and a weakening band of PPN sinks SE.

 

But the air from the Atlantic is barely any warmer aloft than the cold air over the UK. It's close to -10C both ahead and behind, at the 850mb level. Normally I would agree but I think you are not taking into account the unusually cold air source from the NW.

The mean 850 temp is just as low, if anything a fraction colder, once the front passes through:

 

Did you do as I suggested and run the preceip type charts for the GFS? Remember, this is with a much stronger mild sector than GEM and MetO, the only other runs which go out so far (which are any cop!)

Here, this is Tuesday evening as the warm sector slides away eastwards...

EDIT: And the GEFS show the mean values for the warm sector on Tuesday are now -5C or -6C, compared with -7C from the 6z run. Much colder than the op, in other words...

Yes, thanks Darren.

I think the main issue I have is that I just feel (therefore, just a hunch) that it will be diluted as we get nearer the time. I have rarely seen the W deliver widespread snow unless it is a breakdown event and I feel the 850s will be diluted in due course.

I understand that this thread is about analysing the data on hand and in that respect, the points raised are valid enough. However, IMHO, I do find that there is sometimes too much data to look at - especially when it comes to PPN type/intensity/timing; I find these type of charts nothing more than fancy gimmicks, though this is my opinion only.

I understand that this thread is about analysing the data on hand and in that respect, the points raised are valid enough. However, IMHO, I do find that there is sometimes too much data to look at - especially when it comes to PPN type/intensity/timing; I find these type of charts nothing more than fancy gimmicks, though this is my opinion only.

That's one point of view. The alternative is that even forecasting agencies such as the UKM are increasingly dependent on them and make less and less use of manual input / fax charts. 

 

Have you had a bad day at work Ian? Normally I rate your commentary highly for its realism. Today I think you're being unduly pessimistic. 

I guess it is subjective? Ian may be disappointed that the outlook is colder than average rather than mild hence his use of the word “poor”. If like some you are looking for early spring weather then the outlook is indeed poor this evening. There is no big freeze as such but over the last 24hrs the output has shifted*towards a more wintry scenario with the chance of snow for some. Lots of uncertainty and lots of chance for things to go wrong but not “poor” from a cold weather fan’s point of view.

*As Darren has mentioned, as and experience shows, such shifts can also flip back again to a milder outlook.

Bearing in mind the GFS op run wasn’t one of the colder data sets this evening http://wxmaps.org/pix/temp4.png 

 

That's one point of view. The alternative is that even forecasting agencies such as the UKM are increasingly dependent on them and make less and less use of manual input / fax charts. 

Yes, you're right Brian. I think I am still stuck in the dark ages in that respect but I do feel nothing beats a human slant on things.

If the 850s are as low as projected for Tuesday, then indeed there will be snow around for sure. Interesting to see what happens in the days ahead.

 

That's one point of view. The alternative is that even forecasting agencies such as the UKM are increasingly dependent on them and make less and less use of manual input / fax charts. 

12z GEFS snowrow is interesting to say the least.

They don't look that great until you realise its the -5 line and not the 0

 

Have you had a bad day at work Ian? Normally I rate your commentary highly for its realism. Today I think you're being unduly pessimistic. 

That's fair enough, my pessimism is from the fact that the energy is going over the top quickly, very little window for PPN from the East and the worst possible angle of attack from the Atlantic, and regardless of how cold the Atlantic air is behind the front, the damage would be done from the initial warm front unless there is rapid squeezing out of the mild sector.

 

That's fair enough, my pessimism is from the fact that the energy is going over the top quickly, very little window for PPN from the East and the worst possible angle of attack from the Atlantic, and regardless of how cold the Atlantic air is behind the front, the damage would be done from the initial warm front unless there is rapid squeezing out of the mild sector.

Your mate Steve is ramping it up on the other side!

To be honest it all looks very messy at the moment. A lot happening, but since normally the least cold outcome wins, we should probably go with that for now and anything more is a bonus

It seems to me FI is at about day 3 in this situation, never mind the finer detail.  For me, its a case of sit back and wait.

  I've been talking about Thursday 12zs for days now being key in giving us a clear steer on the events of 5th and 6th Feb, but I'm now thinking it will take til as late as Saturday evening before the glass clears.

All extremely absorbing and fascinating.  If I wasn't so busy with work, this would be a highly addictive period of 'unremitting' model watching.

At least we're into the inner reaches of FI (120-144 in this set up) rather than the nonsense of looking at lala land at day 10.

I wont bother getting drawn into discussion of detail til the weekend, and by then , who knows "where we will be?!"

 

 

No. You are totally misreading the synoptics. The cold air is in place over England but warmer air is aloft from the Atlantic. This mixes out the cold layers and a weakening band of PPN sinks SE.

 

You clearly know more than Chris Fawkes then,............when is your first broadcast 

Whereas on the other hand, I am seeing what is probably the best chance so far this winter of us here at . . . * gasps in amazement * Kent getting to see some of the white stuff as we go into the first half of next week (I'm ignoring Saturday's set up as that looks far too sloppy and marginal-like).  But 1) it still looks tenuous/borderline and 2) it is classed as a long way off in forecasting terms anyway. It might end up being like 5th Feb '12 where I got to see a decent snowfall event out of what was a very unlikely looking synoptic, that certainly took me by surprise when I was expecting heavy rain and gale force southerly winds.

<---- Walks over to the other end of this web site to pick up my discarded towel.

And I have to travel to Deal from Folkestone for dental treatment on Monday. Urgh.

 

You clearly know more than Chris Fawkes then,............when is your first broadcast 

It sometimes feels like Brian Gaze is to Frederick Treves as Shropshire is to John Merrick.

https://en.wikipedia.org/wiki/Joseph_Merrick

It seems to me FI is at about day 3 in this situation, never mind the finer detail.  For me, its a case of sit back and wait.

  I've been talking about Thursday 12zs for days now being key in giving us a clear steer on the events of 5th and 6th Feb, but I'm now thinking it will take til as late as Saturday evening before the glass clears.

All extremely absorbing and fascinating.  If I wasn't so busy with work, this would be a highly addictive period of 'unremitting' model watching.

At least we're into the inner reaches of FI (120-144 in this set up) rather than the nonsense of looking at lala land at day 10.

I wont bother getting drawn into discussion of detail til the weekend, and by then , who knows "where we will be?!"

Sums things up nicely for me.

 

Your mate Steve is ramping it up on the other side!

To be honest it all looks very messy at the moment. A lot happening, but since normally the least cold outcome wins, we should probably go with that for now and anything more is a bonus

very sensible as this climate of ours dictates the least wintry outcome very often verifies. With this in mind, most probably a spell of cold rain at the weekend and thereafter a cooler spell looks in the offing, possible wintryness for usual suspects. Nothing major, nothing to bring excitement, just a bog standard phase leading up to the buchan cold spell of mid February 

 

very sensible as this climate of ours dictates the least wintry outcome very often verifies. With this in mind, most probably a spell of cold rain at the weekend and thereafter a cooler spell looks in the offing, possible wintryness for usual suspects. Nothing major, nothing to bring excitement, just a bog standard phase leading up to the buchan cold spell of mid February 

Out of curiosity why are you discounting the risk of snow at the weekend? Do you think the Met Office don’t know how to analyse the NWP output? And secondly a bog standard phase of colder than average weather for wintertime may be a bit more realistic. Bearing in mind that average in winter can be, well, wintry  

 

Your mate Steve is ramping it up on the other side!

To be honest it all looks very messy at the moment. A lot happening, but since normally the least cold outcome wins, we should probably go with that for now and anything more is a bonus

Agree.GEFS 12h is not supportive of the easterly solution.Number  of easterly ENS  at 144h 2,at 240h 4 at 360h 8.

 

Out of curiosity why are you discounting the risk of snow at the weekend? Do you think the Met Office don’t know how to analyse the NWP output? And secondly a bog standard phase of colder than average weather for wintertime may be a bit more realistic. Bearing in mind that average in winter can be, well, wintry  

perhaps, but not so much in the modern era, just ask the good folk of the south who I’m sure will testify that snow is now a rare beast indeed. 

as to the MetO, I’ve lost count as to how many times I’ve heard about snow that doesn’t materialise IMBY, warnings after warnings for nothing. The proof of any pudding is in the eating is it not?