Jayces

Night All, hope everyone gets something snowy over the coming week.

I think some of the confusion is in the timing of the precipitation and what it will be. So, as far as I am aware there is a chance of a light dusting of snow for the SE starting tomorrow night and stopping Monday morning. Then on Monday afternoon a more heavier band is due to arrive BUT within this band there is likely to be sleet and rain. However this is forecast to turn back to snow as the night progresses. The questions will be 1) whether your location is under the sleet / rain possibility and if you are then 2) whether it turns back to snow again before the band passes through. Nobody and I mean nobody can answer those 2 questions.....yet. Yes, we can make a prediction based on the charts but it's changing every 6 hours and we are but a small country and the type of shifts East / West can have a huge impact on us. It's going to get chilly and there might be settling snow in the SE over the next week, that's about a good a forecast as anyone else's ;-)

Was it white rain? ;-)

In his defence what he showed for the 12z run was correct, now it's changed on the 18z s you can't blame him for that? People should listen to what the pro's have said and don't try to predict whether it will snow so far ahead. Just look at the live forecasts and the Meto, they haven't guaranteed anything for Monday because they just don't know.

Not to put a dampner on things but those snow charts are woefully unreliable :-( According to them it should be snowing across the SE right now but it's not. You need to combine them with temperature to see what is going to happen. Yes the current run on the GFS does show the cold being pushed back East slightly on this run meaning the uppers at lunchtime on Monday will be higher hence more chance of rain / sleet for much of this region. Having said that it has moved back and fourth every 6 hours hence my earlier post and others saying don't bother reacting to what may fall until it's a few hours away and no more then 6, especially in this situation where it could be marginal for snow during the day.

Because it's a lower resolution and doesn't discern between snow, sleet and rain. Also £3.49 is nothing and guess goes towards maintaining this great site ;-)

Will it snow in my garden? Please for the love of crimany I need to know so I can cover my daffs and knit woolly jumpers for the birds. Seriously people, the fact is nobody on here, at the Meto, at the BBC, on the international spacestation or even Felix Baumgartner can tell you if it will snow in your location in 36 - 48 hours time because the time is too far away and the conditions keep changing. As Steve already said, 6 hours out tops but even then it's still a guide. Trust me, I have sat here before and watched an intense pink band of snow approach London over the period it took to cross the capital has fizzled out to nothing or another time where it hit warm air and turned green (sleet) and then blue (rain) over my house yet a few miles away it was snow. There is only one way you can guarantee if it's going to snow at your location and that is to observe it at the time, wither through a window or stand outside. The next best thing is to use a weather radar that shows precipitation type (the Net Weather one costs £3.49 for a month and is dead simple) Now.....does anyone know when the snow is coming?

Maybe it's them that are falling?

Nearly splurted cider on my laptop! lol

No point in getting upset, clearly (as has been said many many many times) we will have to see what falls out of the sky when it arrives. Yeah it will be a bitter disappointment after all that ramping if we get rain in the South of the region but no point in worrying about it now as we just don't know whir way it's going to go.

If I don't see snow up to my office window ledge on monday I will be very upset and i'm on the first floor!

We are back to 2 against 1 again but this time the 1 is the model that has the best 5 day verification stats. I think for sanity stick to T72 being FI.

Morning all, big up to John and his great updates and great to see Yamkin back to his old ramping self ;-) I've got me NW radar subscription renewed (thanks Surrey) and there is mostly rain around but sleet from Wolverhampton down to North London and showing it turning to snow around Wolverhampton now. Monday Tuesday looking better and better each day which is great because normally as the events get closer they seem worse. As for beyond that, i'd advise not to take anything beyond T72 for granted. The models just don't know how to handle our current weather. This may be due to the stratosphere thingy who knows. For now chance of snow today but doubt it will settle and then the debate on whether to go to work Monday and risk getting stuck in a snowy rush hour jam in the evening

Or you could use the better radar on this site ;-) Pay £3.49 and it will show difference between rain, sleet and snow too :-)

Ah right I see Kold in the higher res version what you mean. Hopefully the cold air will be further West by then (and colder) so the warm sector doesn't affect us :-) Oh ehmm Sexy in South Norwood?

Sorry I must be misreading the charts but this seems like a massive upgrade on the precip charts for mon / tue so far for us? It shows continues (sp) snow over our area from 7 am saturday to 7 pm tuesday so far?

Thanks Nick, it does beg the question though, why are the models barking up the wrong tree? I am going to guess that they are dealing with data entry at the start of the run that doesn't match up to what they are used to and defaulting to what they have done i the past in those situations and thus the end result is unexpected output? Will be quite a coup I guess for the human LRF's who predict the correct weather if it goes against the computers.

There is this rare condition called snow madness and it's spreading rapidly in here, it causes people to panic needlessly, look way too far ahead for the white stuff and on rare occasions buy their own lampost ;-) Anyway as others have said, the best forecast is nowcasting for snow unless there is a stupid amount coming a few hours away. Tomorrow is a nowcast / radar watching / lampost event. Some may get lucky and see settling snow but I think most in our region will miss out :-( Sunday definitely a radar day as I believe it's odd showers could be anywhere. Monday / Tuesday that could fall in the stupid amounts category (for us anything over a cm is a stupid amount) and monday morning will reveal how much and when but will be more of the long persistent type I expect. I am quietly confident that the whole of our region will see lying snow of some sort over the next 4-5 days but the details still need a lot of fine tuning.

Nick or for that matter anyone who might know, if I am reading that correctly you are suggesting that what is being modelled is a scenario that in the history of computer model forecasting hasn't happened before. Is this because it's just not possible or where you allude to there always being a first time can it actually happen? I mean the models are just a very complex computer program with specific parameters in them, surely they can only produce outcomes that we know are possible because we have programmed them, ie we know hurricanes weaken over land and without wind shear strengthen over warm water so no model will show the opposite ever as they aren't programmed to I guess. But are there unknowns in the weather world still (like the strat effects) that are maybe being added now to computer models and giving us a better understanding of what is really going on and showing scenarios we thought were not possible? Or am I waffling?

I can do my job from home, you clearly can't but if the trains aren't running do you still get paid?

Fingers crossed everyone for a wintry week next week. The massive swing from the ECM compared to 12 hours ago just goes to show how pointless it is to look beyond a few days. I'm still sticking to looking ahead 3 days max for the most likely weather outcome so currently chance of a dusting between now and Monday morning. I am 100% sure there will be snow in the SE between now and then but locations and amounts unknown. Looking ahead out of the reliable (for me) we have the chance of a good amount Monday / Tuesday.but again stress that is still too far out to give details. As an example looking at the last 4 GFS runs for the precipitation for the SE the amount and intensity has increased each time for the same time frame starting with nothing initially and now showing a large amount (this is for 7 am Tuesday). Now consider there are more 15 runs of the GFS it does show the futility of thinking snow is guaranteed that far ahead. We can get a little excited though ;-)

I believe that GP (Stewart) expected a milder incursion at the end of the week before more prolonged cold after that. This morning's ECM just goes to show the futility of looking beyond T72 at the moment, with some 12 degrees temperature difference being shown for 6-7 days away from 12 hours ago.

Sorry was just giving an example of what one was, they can come from a number of places in the UK but I only know how the Thames one works having been under it. The gist is the same if you are in a favourable location with a favourable wind off of the North sea and favourable temperatures as it's al about convection I believe. Someone else can probably list the streamer locations in the UK and where they affect, the Thames one affects the Thames valley to the south of the Thames mainly and spreads SW from there affecting a wider area in a cone shape say from Brighton ish to Isle of Wight....or something like that.

Panicking ;-) Snow can't be reliably or accurately predicted more then a few hours out usually so don't get yourself worked up for next week just yet ;-)

WIth a favourable wind direction ie from ENE for a thames streamer it produces a stream of snow showers that start in the thames estuary and spread to isle of wight widening as they go and giving very crazy accumalations of snow, got a foot before in one night, some people more.