snowking

Precisely what I came here to say when I saw the runs this morning. Wavelengths change, and given the timing of the initial ridge, a slow burner (or freezer) is probably not a bad option to have at this stage. It all still feels a bit too early to me to deliver anything too substantial

If it's early disruption to the fledgling vortex you're looking for, then there are far worse patterns to see at Day 10 than this: We would ideally want a stronger negative Aleutian anomaly, but given these are ensemble means I would be happy to settle for that for now

This is definitely the feature most interesting me at the moment. We get some sort of convergence around that sort of line between 7-9pm initially on the Euro4 modelling of this: This then fades for a while before returning in the early hours This has been there on the last couple of runs, although it could well be gone again come the 12z. I suspect the radar will look significantly less dry than that too in reality

Yeah that had been my first thought James, but it is very much actually melting on contact rather than laying and then disappearing, so it didn't appear to me at least to be sublimation

It's a really strange one, I've just been out for a walk and even on bone dry cars and concrete, with properly powdery type snow, it just seems to melt on contact. The only other thing I could think of is that the wind is having a warming effect (but it certainly doesn't feel like it!). I suspect it just needs something heavy to come down to cover the ground sufficiently to cool it to be honest. Fingers crossed for tonight

6z Euro4 goes very slightly further South with the convergence zone - again remembering what we have already seen, assume that the extent of such a feature is undermodelled, so probably sprawling slightly further North and South than depicted here: Looks to be in a line through approx Norwich - Cambridge - Milton Keynes It will all ultimately come down to a radar watch I suspect, but that sort of zone currently modelled to get something in the region of an additional 5-20cms from what is already lying, perhaps more through that zone in southern Norfolk. Thames streamer also modelled at times, but a bit more coming and going with that feature

Yes it is a little disappointing, it must be ground temps that are just that little bit too high to sustain the covering we did have on concrete at least. Hopefully we can get something a bit heavier in again later and overnight to give us a decent covering that can help cool the ground temperature too. Praying that the convergence zone manages to edge south enough to affect us

I'm not too sure if this has been posted yet, but very interesting FAX charts for the region tomorrow, first of all across the far North of the region: And then a bit further south across East Anglia, running into the west of London and then further south: Now I'll be honest, my experience with convergence zones on FAX charts are that they tend to shift position through until around 12-18 hours before hand, so I'm not getting my hopes up here just yet. However the risk clearly there. They're aligned pretty well to the EURO4 at the moment: Worth bearing in mind with these that as we have seen recently, even high res models struggle to model the overall amount of precipitation. Signs though of something through the Thames estuary too, and noticable that the EURO4 is slightly south of the FAX chart with the streamer through EA tonight: Will be interesting to see how (or even if!) this sets up tonight. Arome pretty well aligned with EURO4 too: In any case, where it does set up, you can see the potential for some very large totals: And a slightly more zoomed in look: Looks to be that zone through North Norfolk and into N Cambs that hits the jackpot. Plenty more of interest over the next couple of days

Yeah eyes on that here too. I’ve got my eye even more on the stuff just starting to form further up the coast into Norfolk (Fakenham sort of area) - if we can get that to form into a streamer that will hopefully be pretty much bullseye for us with a NE-ENE flow. Should be an interesting evening, not expecting more than a covering here and hoping to be pleasantly surprised

This is a good sign - I suspect this is the start of the convection which has formed showers to your north starting to work it’s way south. There may well be a fair bit of this over the next few hours where the snow seems to start without anything showing on the radar (given the 10-15 min delay on the radar vs current time)

Okay, I’ll bite. Probably because it hasn’t missed us? There’s plenty of pictorial evidence to support this. As for “record breaking snowfall”, has anyone actually predicted that? Apologies if they have and I have missed it but I do not recall seeing anyone predicting that.

Absolutely this - compare that to what is shown on even hi res models, and you can see the potential for the next 48 hours

Yeah, where the deepest cold uppers are yet to reach my friend....

If you want an example of how models underestimate convective showers, take a look at the 12z EURO4 prediction for around now Then take a look at what’s happening off the East of Scotland

Huge flakes of snow in the rain here already. Though I think we may now be waiting until tomorrow night to see much more than this

Always fun we start to see showers forecast by the high res models and blowing well inland. What should be even more exciting is that these are almost always underplayed by models.

Presumably then it’s looking even more Impressive than these 12 hourly accum. charts from the 12z which was recently posted:

12z Euro4 completes the set among high resolution modelling to back things further S & E - still looks good around the mouth of the Estuary

I'm afraid aside from the GFS, the trend to push everything further SE is continuing, with the Arome and Harmonie models also significantly further SE than on their 6z runs. At this rate, we might as well just get rid of the system and rely on showers off the North Sea instead

The GFS has actually been surprisingly consistent with this idea for quite a few runs now, it must be some sort of convergence line I just wish it were something other than the GFS!

Hi there. I think we are right on the periphery of proceedings if current modelling is to be believed. Right now I'm not expecting more than a few cms here Sunday-Monday, but I suspect it will be a case of radar watching on Sunday morning and hoping to see things reach a little further North and West than forecast. It could well be a bit of a frustrating one for us looking at it right now, but let's hope for some upgrades

Duplicate - delete

Indeed Nick, I think @kold weather mentioned earlier about previous such events around 2009/2010 which saw this effect happen with some amplification of the precipitation extent and intensity vs modelling when it runs through the estuary, running both North and South. We could very well be into that territory come Sunday. An exciting 72 hours ahead.

For those concerned about being just outside the Amber Warning, probably worth bearing in mind 3 things: 1. It's worth a read of the Yellow warning explanation too, in which it says that 10-20cm is quite possible even within that area the further east you head 2. The warning area and the modelling of the snow will almost certainly move around yet (even just taking a look through the Arome and Arperge ensembles there's still such a large spread) and will again inevitably be different to what is modelled anyway - bear in mind the last two attempts at snow events for our region as a whole have ended up significantly further North than was forecast even 6-12 hours away - this could well end up further North or South by some margin come T+0 3. This only covers this coming weekend. What comes after that is even less model-able, and we've seen many times before many more showers/streamers/longer spells of snow developing and pushing inland than currently modelled. There's a reason broadcast meteorologists are joking around on Twitter about what on earth they are going to say in their forecasts over the next few days as nothing is really off the table. Exciting times though look far more certain for those immediately around the estuary

Indeed Pete. I think a lot of us will be hoping for a bit more of a push North and West when it gets to the reality of the situation.... ....perhaps something like this! Whichever model has fed those graphics, I'll take it