Winter Model Discussion - 12/01/13 06z Onwards

[polarlow2]

I'm really sorry to ask a 'will it snow' question, but there seems to be questions of marginality cropping up for Monday's snow event in the south-east - could I get someone's opinion on that?

[MR EXTREMES]

http://www.metoffice...egionalForecast

and it was last updated this morning at 0400 ok its not updated yet.

Edited January 12, 2013 by model rollercoaster

[lord stratus]

Great news for coldies, latest meto goes for continued cold with severe frosts and more snow, although there is uncertainty from thursday onwards, on balance, a cold solution is favoured..i'm happier now.

Not as cold as most thought it would be next week. Met office actually say it will be on the cold side.

[on the coast]

Great news for coldies, latest meto goes for continued cold with severe frosts and more snow, although there is uncertainty from thursday onwards, on balance, a cold solution is favoured..i'm happier now.

Where have you seen this?

[Polar Maritime]

Where have you seen this?

[Snowman.]

Not as cold as most thought it would be next week. Met office actually say it will be on the cold side.

Which im not buying

They usually underplay the cold when its a few days away.

[IDO]

I'm really sorry to ask a 'will it snow' question, but there seems to be questions of marginality cropping up for Monday's snow event in the south-east - could I get someone's opinion on that?

Quote from UKMO for Monday: An area of sleet and snow will come eastwards across England during the early morning, probably becoming light and patchy later in the morning as it slows down over eastern areas. However, later in the day it is expected to intensify again, at the same time turning back to rain in places. Through the day there is the risk of 5 cm accumulations in places, and more than that above 200 m. However, there is greater than average uncertainty at this range, especially in the extent to which snow affects southern counties, and it is quite possible that the Alert will be upgraded to an amber Warning if confidence increases.

I suspect that caveat is more to do with the fronts stalling. At the moment the suggestion is that the second front will slow/stall in the SE ( and linger on Tuesday in the far SE). However the first front is being modelled to be less of an event for the south, stalling north of this area. Probably will not know till Sunday afternoon. These snow events can upgrade or downgrade very quickly. The closer you are to the coast the less likely for lying snow I would have thought.

liamdutton

Still uncertainty about Monday's snow, but Scotland, central, N'ern & E'ern Eng most at risk. 3-7cm low levels, more hills. #uksnow #c4news

12/01/2013 13:08

A recent tweet again highlighting uncertainty for south/SE.

Edited January 12, 2013 by i'm dreaming of...

[lord stratus]

I'm really sorry to ask a 'will it snow' question, but there seems to be questions of marginality cropping up for Monday's snow event in the south-east - could I get someone's opinion on that?

Basically the precipitation is not coming from a great direction so unfortunately there will be warmer uppers in the mix, meaning rain for some.

This is not as straight forward as say easterlies bringing in convective showers or a channel low.

There are complications with a channel low however if it travels too far north it would mean warmer uppers to the south of the low would mix in with the cold uppers. I think the snow/rain event will have to be a wait and see event.

[manutdmatt1986]

Quote from UKMO for Monday: An area of sleet and snow will come eastwards across England during the early morning, probably becoming light and patchy later in the morning as it slows down over eastern areas. However, later in the day it is expected to intensify again, at the same time turning back to rain in places. Through the day there is the risk of 5 cm accumulations in places, and more than that above 200 m. However, there is greater than average uncertainty at this range, especially in the extent to which snow affects southern counties, and it is quite possible that the Alert will be upgraded to an amber Warning if confidence increases.

I suspect that caveat is more to do with the fronts stalling. At the moment the suggestion is that the second front will slow/stall in the SE ( and linger on Tuesday in the far SE). However the first front is being modelled to be less of an event for the south, stalling north of this area. Probably will not know till Sunday afternoon. These snow events can upgrade or downgrade very quickly. The closer you are to the coast the less likely for lying snow I would have thought.

liamdutton

Still uncertainty about Monday's snow, but Scotland, central, N'ern & E'ern Eng most at risk. 3-7cm low levels, more hills. #uksnow #c4news

12/01/2013 13:08

A recent tweet again highlighting uncertainty for south/SE.

There seems to be a warm sector on the second low which looks like hitting areas to the south of London, potentially ruining what would otherwise be a good snow event for me.

Edited January 12, 2013 by manutdmatt1986

[Geordiesnow]

One thing I will say about the ECM is that on yesterdays 12Z run, it had a better amplified ridge in the short term(first 72 hours) thus the shortwave went up to the SW of Greenland, today's ECM came into line with the UKMO/GFS run with having the shortwave coming across and landing to the south of Greenland so it shows even in the short term, even the ECM can get minor details incorrect.

I think sods law will tell us the ECM is more likely to be correct, but as per ever, its a wait and see process, hopefully the 12Z runs will give us a little bit of a clue as to what may happen around mid-week onwards.

Edited January 12, 2013 by Geordiesnow

[Frosty.]

It's not being underplayed at all (MO UPDATE), it's a cold outlook very much in line with the gfs 06z actually with sharp frosts and sleet and snow, compare that with the mild dross over christmas and new year!

Edited January 12, 2013 by Frosty039

[iowpompeylee]

With the ECM starting to swing.it looks like the temps. especially in the very south look a lot milder according to the met office.this cold snap might not be turning out to be what everyone thought.i do hope I'm wrong.been model watching for a week now chasing the holy grails of runs.....the runs tonight will rubber stamp the situations

[Su Campu]

Taking the models' word for it just up to 96 hrs and going on experience thereafter, I still see no real signal for substantial northward height builds and a retrogressive pattern out to 10-12 days. I still think a slow progressive pattern will preclude much westward cold extension, but SE England is always in with a chance of a brief glancing blow. I think we'll see NAO forecasts take a bump upwards from what they've been showing.

After that of course it's all to play for as we see how the SSW propogates.

Edited January 12, 2013 by Su Campu

[Frosty.]

the runs tonight will rubber stamp the situations

I don't think anything will be rubber stamped today, it remains an extremely complex picture, although thankfully, a cold and complex picture for the vast majority of the uk with only the far west exposed to something less cold at times.

Edited January 12, 2013 by Frosty039

[Buzz]

Those worrying about the ECM for next Thursday (5 days away!) should read Chiono's recent post in the Strat thread:

[Methuselah]

Great news for coldies, latest meto goes for continued cold with severe frosts and more snow, although there is uncertainty from thursday onwards, on balance, a cold solution is favoured..i'm happier now.

No probs peeps: come Thursday, we'll all have no power, no transport network and no net-weather; and our front doors will be sealed-up, by fifteen-foot deep snowdrifts!

[MR EXTREMES]

Quote from UKMO for Monday: An area of sleet and snow will come eastwards across England during the early morning, probably becoming light and patchy later in the morning as it slows down over eastern areas. However, later in the day it is expected to intensify again, at the same time turning back to rain in places. Through the day there is the risk of 5 cm accumulations in places, and more than that above 200 m. However, there is greater than average uncertainty at this range, especially in the extent to which snow affects southern counties, and it is quite possible that the Alert will be upgraded to an amber Warning if confidence increases.

I suspect that caveat is more to do with the fronts stalling. At the moment the suggestion is that the second front will slow/stall in the SE ( and linger on Tuesday in the far SE). However the first front is being modelled to be less of an event for the south, stalling north of this area. Probably will not know till Sunday afternoon. These snow events can upgrade or downgrade very quickly. The closer you are to the coast the less likely for lying snow I would have thought.

liamdutton

Still uncertainty about Monday's snow, but Scotland, central, N'ern & E'ern Eng most at risk. 3-7cm low levels, more hills. #uksnow #c4news

12/01/2013 13:08

A recent tweet again highlighting uncertainty for south/SE.

well 09/10 07/08 we had good snowfall here on the southcoast so i dont disscount anything.

[Frosty.]

No probs peeps: come Thursday, we'll all have no power, no transport network and no net-weather; and our front doors will be sealed-up, by fifteen-foot deep snowdrifts!

i agree with that but no netweather would be a nightmare, lets have the 15 foot snowdrifts though

[Southender]

Quote from UKMO for Monday: An area of sleet and snow will come eastwards across England during the early morning, probably becoming light and patchy later in the morning as it slows down over eastern areas. However, later in the day it is expected to intensify again, at the same time turning back to rain in places. Through the day there is the risk of 5 cm accumulations in places, and more than that above 200 m. However, there is greater than average uncertainty at this range, especially in the extent to which snow affects southern counties, and it is quite possible that the Alert will be upgraded to an amber Warning if confidence increases.

I suspect that caveat is more to do with the fronts stalling. At the moment the suggestion is that the second front will slow/stall in the SE ( and linger on Tuesday in the far SE). However the first front is being modelled to be less of an event for the south, stalling north of this area. Probably will not know till Sunday afternoon. These snow events can upgrade or downgrade very quickly. The closer you are to the coast the less likely for lying snow I would have thought.

liamdutton

Still uncertainty about Monday's snow, but Scotland, central, N'ern & E'ern Eng most at risk. 3-7cm low levels, more hills. #uksnow #c4news

12/01/2013 13:08

A recent tweet again highlighting uncertainty for south/SE.

Which is exactly why I said earlier there is more concern about how much ppn will be left on the fronts. So often I have seen fronts decay and have very little left on them, after they have crossed the whole country.

Hopefully that will not be the case and the ppn holds together by the time it reaches us and gives us a good covering.

Marginality not so much of an issue the further North and East you are in our region.

[TrickyRicky]

With the ECM starting to swing.it looks like the temps. especially in the very south look a lot milder according to the met office.this cold snap might not be turning out to be what everyone thought.i do hope I'm wrong.been model watching for a week now chasing the holy grails of runs.....the runs tonight will rubber stamp the situations

With all due respect, there'll be no rubber stamping tonight. People have been trotting out that old chestnut for days now and nothing is sorted yet. Remember record Shannon Entropy means the models are all over the place.

[Buzz]

With the ECM starting to swing.it looks like the temps. especially in the very south look a lot milder according to the met office.this cold snap might not be turning out to be what everyone thought.i do hope I'm wrong.been model watching for a week now chasing the holy grails of runs.....the runs tonight will rubber stamp the situations

Not a chance. And as for temps in the very south being "a lot milder according to the met office" - they said no such thing. Here, I'll cut and paste their outlook from today and put in bold the most important sections:

"UK Outlook for Thursday 17 Jan 2013 to Saturday 26 Jan 2013:

There remains a lot of uncertainty in the details throughout this period, however on the whole it should remain on the cold side across many parts of the United Kingdom, with a good deal of dry and frosty weather, especially for central areas. There will also be some sleet and snow to watch out for on occasion, with perhaps eastern areas most likely at risk seeing any significant snowfall. Also there will be an ongoing risk of icy stretches overnight, and freezing fog may also be an issue during the cold and clearer nights. Some milder conditions and more persistent rain and hill snow though may fringe into western areas on occasions throughout the period."

Do note that this starts on Thursday, well into what we are currently seeing as FI in the model output (which is about 72 hours).

[lord stratus]

well 09/10 07/08 we had good snowfall here on the southcoast so i dont disscount anything.

Different set up though. However this may change and the set up may improve as we get closer to the event.

[cyclonic happiness]

No probs peeps: come Thursday, we'll all have no power, no transport network and no net-weather; and our front doors will be sealed-up, by fifteen-foot deep snowdrifts!

It'd better be, or you're in trouble

[Polar Maritime]

I don't think anything will be rubber stamped today, it remains an extremely complex picture, although thankfully, a cold and complex picture for the vast majority of the uk with only the far west exposed to something less cold at times.

Yes Frosty, what with the complicated set-up and the SSW taking hold nothing will be rubber stamped out from 3/4 days out, something we will have to get used to over the next week or so...

[lord stratus]

With the ECM starting to swing.it looks like the temps. especially in the very south look a lot milder according to the met office.this cold snap might not be turning out to be what everyone thought.i do hope I'm wrong.been model watching for a week now chasing the holy grails of runs.....the runs tonight will rubber stamp the situations

It could turn out to be a non event. The trouble is that a lot of members are so desperate for a cold and snowy spell that they are ramping up snow events from the north west! These events are always marginal! I expect to see a few surprises this week though!