Model output discussion 10/02/21

[Frosty.]

11 minutes ago, johnholmes said:

Definitely the prediction can be rated pretty severe. Even the change from the very mild/warm of a few days ago to the next 24 hours when, here for example, there was a drop from 24.1 to 6.3 C in 24 hours, a drop of 14.2 C. In mid winter that would have been unusual for a fall of 14 C. Similarly the maxes of 6-8 C for Monday would be some 6-10 C lower in mid winter so pretty unusual synoptics I would agree.

Indeed, and between the strong spring sunshine when showers blow through in the arctic air flow the temps will drop like a stone to near freezing point..much colder for Scotland of course...anyway..it’s going to feel bitterly cold in that Northerly wind and nights will be frosty where skies clear with icy patches from late showers and some temporary accumulations, especially early & late..think that covers all bases! ..oh and.. thunder & lightening for some..looking forward to the yellow / amber / red weather warnings!   

Edited April 2, 2021 by Jon Snow

[Griff]

T - 60....

[Griff]

Fffffffff scorchio....

Edited April 2, 2021 by Griff

[Mike Poole]

UKMO T850s T72 and T96, and it is a direct hit once more:

We need to keep our eye on this, because the scenario picked up in the occasional ensemble run in recent days of the purple slug making it all the way to the UK, can’t as of yet be totally discounted!

[Cheshire Freeze]

9 minutes ago, Mike Poole said:

UKMO T850s T72 and T96, and it is a direct hit once more:

We need to keep our eye on this, because the scenario picked up in the occasional ensemble run in recent days of the purple slug making it all the way to the UK, can’t as of yet be totally discounted!

UKMO is a lot better than the GFS for instability and thus shower activity. GFS has edged the pattern east slightly on both the 6z and 12z runs. Not a trend I'd like to see continued.

[Griff]

GEM  

[Britneyfan]

Personally if your in the south apart from some wintry showers Monday with a cold wind chill still plenty of sunshine and temps up to 11 degrees by Thursday

[ICE COLD]

Really is impressive cold for April -14s in Scotland-11 to -12 quite widely for everyone else

[Empire Of Snow]

Atlantic vs Arctic at 174h for a reload. If Arctic wins it's going to be another very cold blast. 

[ICE COLD]

The Gem has -15 850s in Scotland and down to -13s in London 

[Griff]

3 minutes ago, Empire Of Snow said:

Atlantic vs Arctic at 174h for a reload. If Arctic wins it's going to be another very cold blast. 

Looks cold

[ICE COLD]

6 minutes ago, Empire Of Snow said:

Atlantic vs Arctic at 174h for a reload. If Arctic wins it's going to be another very cold blast. 

Looks like the cold Arctic air is gonna win . 

Edited April 2, 2021 by ICE COLD

[Empire Of Snow]

1 minute ago, ICE COLD said:

Looks like the cold Arctic air is gonna win . 

Briefly yes. Still this is deep in FI. 

[BlueHedgehog074]

Wow, am amazed lol! Have resisted looking at the models for the last few days and am astonished they’re still going for a cold Northerly early next week! (Maybe a touch Westward shift for the Northerly on the GFS would be nice though, otherwise a chance for a wintry mix of sleet, graupel, hail and snow showers for places, particularly towards Eastern UK). Possibly with further attempts as High Pressure to our West tries to re-amplify. 

While I am looking forward to some warmer weather, aside from the spell some of us had earlier this week, I feel like it’s paid off avoiding looking at the models in the last few days. Guess it’s always possible the Northerly could still go a little bit too far East with more places remaining dry. But considering it’s not that far away now, that is probably unlikely - particularly for Easter Monday, where it looks like it could be a direct hit for the UK. The thought of seeing quite a potent Arctic blast at this time year - one that again looks chilly enough for some wintry weather, makes me want to take one last trip on that Polar Express before Spring sets in deeper

[Thundery wintry showers]

Still some uncertainty on how far west this northerly ends up, I am watching with interest as this setup has potential to bring a rare April snowfall here in Exeter (I think the most that I can expect on the ground is a brief dusting early on the 6th, like happened in Exeter on 6 April 2008, but any wintry weather is noteworthy here at any time of year, let alone this late in the season).  GFS at T+72 has the main "thrust" of the northerly going down the east of the UK, though it does have a feed of showers heading through Wales into the West Country overnight 5th/6th despite pressure of around 1025mb:

However, the UKMO has the main thrust of the northerly further west hitting the whole country:

Indeed, tonight's UKMO out to T+144 is a very wintry run with a second potent northerly likely out at T+168.  It's worth noting that the GFS still has very cold 850hPa temperatures hitting the whole country, just with higher pressure possibly meaning fewer showers generally especially in the west.

For the longer term, potential for another switch-around back to warm sunshine, or at least a transition to settled weather with temperatures closer to normal, some sunshine by day and chilly nights, with high pressure building from the west, though there's a fair chance of another northerly blast or two before this happens.

This morning's ECMWF was more similar to the current GFS, though with the northerly a little further west than on the GFS.

Edited April 2, 2021 by Thundery wintry showers

[Methuselah]

So, after a week of decent snow-chances, things still look like becoming a tad more spring-like, as we approach mid-month:

    

[I remember Atlantic 252]

big advantage at this time of the year, if cold fails it may not be vile, unlike in Dec to early March, good chart for first day of retail

[Dancerwithwings]

10 minutes ago, I remember Atlantic 252 said:

big advantage at this time of the year, if cold fails it may not be vile, unlike in Dec to early March, good chart for first day of retail

I don’t think for some reason peps are interested in and what the weather will be when the shops open next week !!!

its this Monday, look at the drop on that  

T

 

Edited April 2, 2021 by Dancerwithwings

[Dominic Carey]

I’m hoping for a major last minute shift of cold as next week’s charts look positively vile for us southerns cold and wet yuck. Enjoy your snow northerners.

[Mike Poole]

GEFS minimum, 50th percentile, and maximum across the suite at T78:

Cold is nailed on, but the uncertainty exists about the depth of the cold even as early as this, as shown by the various op runs too.

Edited April 2, 2021 by Mike Poole

[Methuselah]

Wouldn't it be grand, were we to be welcomed out of lockdown (and into the beer garden!) by something like this? 

    

Edited April 2, 2021 by General Cluster

[Cloud 10]

Crazy cold gefs member of the day goes to lucky  7,which almosts gets to the -20

 

[Dancerwithwings]

11 minutes ago, General Cluster said:

Wouldn't it be grand, were we to be welcomed out of lockdown (and into the beer garden!) by something like this? 

    

That’s more like it, that’s the type of shopping I’ll be doing

[The Northern Ramper]

35 minutes ago, General Cluster said:

So, after a week of decent snow-chances, things still look like becoming a tad more spring-like, as we approach mid-month:

    

Open the pubs

[Frosty.]

One of the joys of the anticipation of a major cold plunge for me is viewing the dam thicknesses nose diving at 3h intervals..does anyone else like doing that?..or am I just a weird cold weather enthusiast? ..may raise a few eyebrows!