Pembroke Dangler

Trigger low will drop into France and then we have a scandi Russian high link up.

This is a boom chart for us southern wales folk right here all snow as we are on the northern flank, please let this verify we do have cross model agreement of sorts for Tuesday of a channel low with wales on the north side of it.

It’s better that it’s no storm because with deeper low pressure is likely to lift the colder uppers out ahead of the system meaning more rain than snow hope that clears it up

If we can retain heights in the area in the red box I drew and the energy goes under exiting the esb I think we will be in business.

Looks a very slack pressure chart good for retaining the cold ahead of the system could be good this bank it

Will it go north will it go south all up for grabs but hopefully we hit the jackpot my fingers are crossed for a good old dumping of the white stuff

That’s the 00z going by the 6z running out now you can shift that lot about 200 miles south

Snow in the Swansea snow dome let’s have it

From what I can remember just before last years beast the models couldn’t get to grips with the position of the high pressure to our north and just 3 days before it came, the ecm showed the main thrust of cold heading to France and north Spain, before just the next day a north correction and we were in the sweet spot so I’m going to give it until Monday 12z before calling it, we might just get this easterly you never know .

They have but it’s now under 120 hours until it unfolds so time is of the essence here and I just think barring a monumental back track in the next 36 hours max then it’s a done deal and the Euro trough will sink to far south east allowing the Azores high to topple in over us rather than to the north of us.

Shocking run to run consistency across the board really none have painted themselves in glory in the reliable time frames upto 120 hours wobbles or not it’s not good. UKMO charts ecmwf gfs take your pic they all have been woeful this last couple of days. So on that note I’m out to.

Yeah your right it’s fragmented and you can see the why it’s definitely waiting for some back up from the south which would be the warm sector I would imagine

The front approaching over Ireland looks like it’s stalling and pivoting could be a few surprises and the air is definitely got an easterly element out there tonight could be a now cast thing come the morning

Could be retrogression to Greenland here allowing cold reinforcement from the north east then we are locked in for cold for a while.

Snow moving from west to east on that front nothing marginal here -4 -5 uppers drawing a continental feed ahead of the front very nice indeed

Would you look at that the Swansea snow shield has been breached hooraaa

Not like you Steve to forget how to spell snow model fatigue maybe setting in have a break mate cold is coming snow will follow

It can also depend on Sea Ice extents in the arctic circle but due to climate change and less sea ice compared to about 30 years ago the modifying is more extreme due to less ice over our side of the pole so the modification of the air mass is quicker. I think there’s a learning thread that bb62/63 posted in before explaining this in more depth.

The system travels over a relatively warm ocean surface to reach us so milder air can mix out the colder air aloft as it moves from north to south where as the states has no warm sea for the airmass to get to modified so cold uppers remain intact as it moves north to south.

Could do with system being about 200 miles further east so more of a direct northerly would allow less mixing of the airmass over the Atlantic still cold enough for snow with modest elevation in the south less height required up north probably need to be away from the coasts though. Temps around 0-3 north of Manchester 3-6 south of Manchester hence elevation required

History will tell us these slider scenarios always tend to come down to now casting and more often correct south and west as the models firm up on the position of the Azores high being further displaced in the mid Atlantic. Also the sliders themselves tend to be less rounded and more sharp as they move through on a nw/se axis.

I’d bank this one cold air in place sliding lows and all still in winter ?

I believe the fi frames on the 6z will be most welcome, and judging by what Nick F posted a few pages back with the lag effect of the MJO and coupled with the ssw downwelling lag we may see a period in between where cold zonal will be the form horse before amplification in the mid Atlantic linked with MJO phase 7/8 arrive and I believe a link up of the arctic high forming over the pole linked to the ssw downwelling will then get us to the holy grail and lock in cold for a good spell. I would include pics but can’t as on my phone. Its been a painfully slow process it seems but, a process allot of the pros have been talking about on here and on social media. Patients is the buzz word it seems and we will need to be but rewards will be coming in plentiful supply starting with sliders and raw nw winds followed by a true arctic northerly.

That’s what we want to see develope a low over Iberia just needs to take root. Happy new year all here’s hoping for a snowy last few months of winter

The U.K. high will migrate nw towards Greenland dragging the higher heights away from Iberia allowing the pv to drop over Scandi and an undercut of low pressure meeting it heading to where the high used to be over Spain and caboom locked in cold.