London And The South East Regional Discussion Thread - II

[winter watcher]

some bad news here.. its raining, just come in from mates just 10mins down the road, yep def raining, could be dew points aint that low yet?

See i have seen snow tonight but because of the rate its falling it is just turning wet on cars and roofs ect. So i would guess the same applies nanu?

[danm]

Do Thames streamers affect North London?Good luck you guys anyway, I hope im more lucky with the event later in the week, the one Roger was talking about.

Depends on the wind direction. For north London (particularly north west London) to be affected by a Thames streamer, you need more of a straight easterly. Sometimes an ENE can also deliver, depending on how much the showers push inland and not fizzle out. An ESE wind would be ideal for north London.

In November 2010, the wind was generally ENE and the worst affected regions were SE Essex, NW Kent and SE London - many in those areas got nearly a foot of snow. However, i'm in NE London and i still got several inches of snow from that event. However, many people in NW London, just 10 miles west of me, were complaining about getting absolutely nothing.

[danm]

some bad news here.. its raining, just come in from mates just 10mins down the road, yep def raining, could be dew points aint that low yet?

There are spits of rain in it :(

Damn.

Obviously not quite cold enough just yet.

[PureOcean]

One thing I will say is that this is building and widening gradually, its covering more ground and is certainly interesting. Not going to bed for some time, as this is a different weather event and I am intrigued.

[winter watcher]

Even if it has fallen as light rain for some it proves one thing to me. That no chart can predict streamers and local snow events even at t6+ i would therefore take no notice of the BBC forecast and the meto forecasts and instead stick to radar and this thread for guidance. The BBC and Meto seem to me a good bet to follow when a large scale snowfall is predicted and even then they are prone to balls it up.

[Gowon]

You lot reckon those showers will reach Croydon? Debating whether to call it a night.

[95 Degrees]

Very Light Prepiciption moving down towards coastal Sussex? thats what Rain Today is showing, temp is 0.9C.

Edited January 31, 2012 by BrightInBrighton

[PureOcean]

This convergence and the way its building is very similiar to lake snow effect that I have encountered in the great lakes a few times. Not exactly the same but certainly interesting. Does make me laugh as the BBC weather team all never mentioned snow or anything in Kent really, and yet I have been telling family and friends that I thought this exact thing would happen - I am convinced they stick heads and eyes in laptops and dont look outside at the conditions.

[Biggin]

You lot reckon those showers will reach Croydon? Debating whether to call it a night.

Bout another hour n half 2 hours yet if it does

[PureOcean]

Bout another hour n half 2 hours yet if it does

Longer still as this is very very slow moving, its just spreading, I would doubt it would go that far west, but yet never know!

The geography of where it has come in, is flat marsh land spreading upwards to hills towards Canterbury. Be interesting to see how it copes moving inland.

[Neilsouth]

Naff

[Gowon]

Thanks for the replies, I think I'll call it a night and hopefully wake up to a nice covering :winky:

[Paul Sherman]

Well I have seen enough of the last 2 radar runs to call it a night and it is only 30 odd miles to my SE. Pretty sure this is a Kent Clipper, winds veered back to a more Northerly Componant around that area just recently. Expect Ashford and Canterbury to be the limits of Inland Motions, mixture of snow, sleet and slops around Herne to Ramsgate etc.

Lets see what tomorrow's models bring

[essexweather]

Quick post before leaving the office, and not good news.

The Met Office are relying heavily on their 'MOGREPS' and own ensemble data for this weekend's breakdown. Looking at the most recent postage-stamps there is VERY high confidence of a quick breakdown with more than 70% showing the cold leaving the East coast by Sunday. 20% keep a anti-cyclonic Easterly and the other 10% mixed.

The MOGREPS has performed very well in these situations since inception in 2006 and can see why Exeter are happy with tonights FAX charts and new 7-15 day text outlook. We will most likely see further downgrades tomorrow in the new issue around 11.30Z.

Anything can happen beyond T+120 and we will most likely see the continental feed return in 10-15 days time. However, time is running out for this winter.

Keep positive, it could be all change when the 00Z runs and ensembles arrive.

[Robbie Garrett]

[Snow Queen one]

In car on a2. Just been to cover TOT white did not even attempt to go down hill to cover town. Now just outside canterbury and it is sleet. Off down m20 in a mo the pink blob on radar for canterbury is a mix of sleet and snow

[Snow Queen one]

I meant dover predictive txt fail

[polarlow2]

Depends on the wind direction. For north London (particularly north west London) to be affected by a Thames streamer, you need more of a straight easterly. Sometimes an ENE can also deliver, depending on how much the showers push inland and not fizzle out. An ESE wind would be ideal for north London.

In November 2010, the wind was generally ENE and the worst affected regions were SE Essex, NW Kent and SE London - many in those areas got nearly a foot of snow. However, i'm in NE London and i still got several inches of snow from that event. However, many people in NW London, just 10 miles west of me, were complaining about getting absolutely nothing.

I can vouch for that. In Hanwell, west London we got a dusting from several hours of light snow while south-east London got hammered. Frustrating.

[Buzzit]

The Met Office are relying heavily on their 'MOGREPS' and own ensemble data for this weekend's breakdown. Looking at the most recent postage-stamps there is VERY high confidence of a quick breakdown with more than 70% showing the cold leaving the East coast by Sunday. 20% keep a anti-cyclonic Easterly and the other 10% mixed.

The MOGREPS has performed very well in these situations since inception in 2006 and can see why Exeter are happy with tonights FAX charts and new 7-15 day text outlook. We will most likely see further downgrades tomorrow in the new issue around 11.30Z.

I assume you mean they are using the MOGREPS 15 day ensemble and UKMO ensemble as the basis for their forecast ?

[WheresTheSnow]

Thanks for the reply danm, we usually get a fair amount of snow wherr I am, clearly not this winter yet. I saw a chart earlier that looked good for snow tommorow afternoon, is this the case? Shame its raining for some, you wouldve thought it was cold enough for snow.

Also im not sure im part of this thread but nevermind, a lot more ramping goes on in here than 3 counties thread!

[essexweather]

I assume you mean they are using the MOGREPS 15 day ensemble and UKMO ensemble as the basis for their forecast ?

Yes, on the earlier conference call they totally dismissed the American model (GFS) and stuck with their own model out to T+120 and then used the ECM out to day 10 with some confidence.

It was noted that the colder air hangs on longest in the SE with a increased snow risk around days 5 and 6.

[danm]

Yes, on the earlier conference call they totally dismissed the American model (GFS) and stuck with their own model out to T+120 and then used the ECM out to day 10 with some confidence.

It was noted that the colder air hangs on longest in the SE with a increased snow risk around days 5 and 6.

Do you work for the Met? How were you involved in this conference call?

[Paul Sherman]

Dont want to sound harsh but 2 of the lines in your Signature need changing if the Met Office are so on the ball.

[winter watcher]

Quick post before leaving the office, and not good news.

The Met Office are relying heavily on their 'MOGREPS' and own ensemble data for this weekend's breakdown. Looking at the most recent postage-stamps there is VERY high confidence of a quick breakdown with more than 70% showing the cold leaving the East coast by Sunday. 20% keep a anti-cyclonic Easterly and the other 10% mixed.

The MOGREPS has performed very well in these situations since inception in 2006 and can see why Exeter are happy with tonights FAX charts and new 7-15 day text outlook. We will most likely see further downgrades tomorrow in the new issue around 11.30Z.

Anything can happen beyond T+120 and we will most likely see the continental feed return in 10-15 days time. However, time is running out for this winter.

Keep positive, it could be all change when the 00Z runs and ensembles arrive.

Unless you work for the met office mate i would suggest you remove the post before people start questioning this and here is why:

First point: Yes the Meto have access to models we do not see but they seem to be siding with the ukmo which is all to progressive with the pattern and within the reliable we keep noticing short term upgrades within t72+ i.e the block being modeled further west and the recent tweets from the pros state high uncertainty i.e there sitting on the fence.

Second point to add: The Meto state that the only place to likely see milder conditions returning is the far north west of england and not the south east of england unless you class max temps of +1c to 4c tops before signals and outputs are suggesting a further plunge of cold weather to the united kingdom.

Third and final: Have you seen the latest BBC and Meto forecasts suggesting that this period is likely to be mainly snow less? Well tonight we have seen parts of the region hit by snow showers and a streamer setting up although not nationwide suggests to me that the BBC and METO are very much underplaying the chances for snow in the very near future.

[essexweather]

Do you work for the Met? How were you involved in this conference call?

I work for a private forecasting company and in charge of gritting for a number of councils so lucky enough to be kept in the loop when it comes with data and discussions.

Personally, I wouldn't put all my confidence on one model and one set of ensembles - but the MO havn't put a foot wrong yet this winter.

Edited January 31, 2012 by essexweather