Panayiotis

You've posted the wrong chart for the 06Z, that's yesterday's

The PV moving away from Greeland with height rises replacing it has definetely gained momentum in the last 24hrs, really looking forward to tomorrow's runs as I feel something is awaiting... To the medium term, the PM incursion looking increasingly cold, with snow showers just about anywhere once the cold air gets established

JMA showing the two pressure attacks on Greenland beautifully:

GFS showing the 'double attack' of pressure rises over Greenland which I alluded to in yesterday's post. The low pressure hits the block to our west, which leaves it unable to go anywhere hence dragging the PV down and away from Greenland towards the U.K. In doing so it feeds a prolonged NW flow, which in itself gives a lot of oppurtunities for snowfall especially for N and W areas. Again it must be noted how this same low pressure drives heights from Scandinavia towards Greenland (first animation) - Pressure Attack 1 With the PV away from Greenland (and filling over the UK) it leaves a window of opportunity (around day 10/19th) for a pressure rise from the Atlantic (i.e. animation 2)- Pressure Attack 2 UKMO shows the first pressure attack a lot more clearly than the GFS. A linkup of these heights could help us deliver a Greenland high, which is something I'll be keeping my eye on for the next few days to see how developments go.

Ive been more of a lurker this winter regarding posting in this thread but heres a post on my thoughts. I think its fair to say (as mentioned by some) that the quest for a near-term easterly (which could deliver snow) is quickly becoming non-existent. The closest we get to a feed off the continent is from the SE which originates from Greece @120hrs and with no deep cold pooling over Europe, this is only likely to bring upper air temperatures just below 0C. Looking at those charts from 120hrs, Im finding it difficult to see where a potential easterly (cold and snowy type) could come from. The centre of the high on all of the models is located over Russia, which is in completely the wrong place for the UK to benefit as the flow and subsequently colder temperatures are directed towards Turkey/Black Sea. Despite the MLB not directly delivering for the UK, I think it will help us in the longer term. All the charts above also have another feature in common: a raging and circular PV over Greenland. Its after this point (120hrs) where there is developments for low pressure to move away from Greenland, and in doing so it faces the block to the east. Its this low pressure which delivers the polar maritime air mass forecast for the UK, and because its unable to move away due to the block, it keeps the PM feed for longer. The interesting trend which I'm picking up on is that the same low pressure which delivers the cold PM air to the UK is also responsible in driving away the PV from Greenland. Charts below are for 168hrs: From experience when the PV moves away from Greenland, it is replaced by a pressure rise. Now if the low pressure can dig SE (as shown by the models) then we will see a movement of the heights from the MLB on the NE flank of the low. Hence what I'm looking for is a double 'attack' of pressure rises over Greenland, one from the east and one from the south. For an example of what could happen, I give the 00z run from the NASA model:

Surprising to see bristol getting heavy settling snow and not here in Cardiff. We had heavy wet snow a hour ago but turned back to light rain/sleet/snow. Front starting to swivel around now, seems to be stalling just east of Cardiff.

Heavy wet snow in Cardiff town about a hour ago, turned to light sleet/rain with snowflakes mixed in. Radar suggests front swivelling around Cardiff with moderate PPN but not much falling anymore

Yes PPN starting to pep up in places now, probably to do with the moisture flux from storm Ana to the south....

Warmest temperature today was 3.6C which was during the early hours! As for when the sun came out, temperatures have not gone over 2C which is quite extraordinary especially as bbc weather yesterday night had Cardiff forecast to reach 8C today with heavy rain. This has slowly backtracked throughout the day. It's been snowing on and off here with some accumulations on cars/grass etc

Try screenshotting the image...

It's settled here a bit though from earliers heavy snowfall, covering on roofs/grass/cars

Yeah mixture of rain, sleet and light snow now

Snowflakes the size of a 50p here now!

Yeah moderate to heavy snowfall here in Cardiff still surprised to see no warning from MetOffice. The snow line has definetely shifted south...

Heavily snowing here in Cardiff, settling now after raining all night...

Just a quick look at some of the high res models for the feature we have currently stretching across the country. Radar below just so everyone knows what feature I am talking about: Now a look at the EURO4, NMM 2km, AROME 2.5km, ICON and ARPEGE at 3am: ICON and the ARPEGE dont make much of the feature however the other models seem reasonable with the extent of the PPN band but have it shifted north compared to the realtime radar. I feel as though this really puts a real sense into how difficult it will be to forecast the slider for this weekend and where the associated snow risk will be...

Light Snow, sleet and rain here in Cardiff with DPs below 0C

I wonder if the storms entering the UK in the SW and the storms currently over thw S will 'blow' up as the sun sets... great watching nevertheless!

Quick developments north of London by the looks of the satellite, with some of the cloud tops casting shadows I would expect some action there this afternoon. Also that MCS over NE France is a beauty, people in Kent should be having their eyes right on it!

One flash (just to the south) and some thunder followed by some intense rain. Nice to see!

Ice crystals/sleet falling for most of the morning here. At times there was brief snow showers with varying sizes of snowflakes. PPN to the NE looks decent, however it arrives when I'm out the county, so good luck to all today/tonight! PS: While I was writing this, it started to snow a bit more heavily (small flakes)

After being below 0C all day, the DP has risen above freezing in the last two hours, not conductive for snow at this present time:

Been snowing on and off all day here in Reading (very lightly) but it picked up a bit in the last 20mins. Peculiar as radar doesnt show much, quite a good sign as the more unstable air is predicted for tomorrow and Saturday....

Lightly snowing here in Reading

Very cold run for the next 2 months from the CFS 9month! http://www.meteociel.fr/modeles/cfse_cartes.php?ech=1254&mode=0&carte=0&run=0