Model output discussion 10/02/21

[Guest]

Looks almost impossible to avoid a below average CET for looking at GFS this evening. Would either a ridiculously mild second half of the month or a complete capitulation of the forecast northerly.  

Either way its grim across the board, UMKO, GEM, ICON all back up GFS showing the cold hanging around well into next week.

[Frigid]

4 minutes ago, Alderc said:

Looks almost impossible to avoid a below average CET for looking at GFS this evening. Would either a ridiculously mild second half of the month or a complete capitulation of the forecast northerly.  

Either way its grim across the board, UMKO, GEM, ICON all back up GFS showing the cold hanging around well into next week.

We said that about February with regards of it being near impossible for a warmer than average month during the first week, and look what happened. 5.1c CET. I wouldn't be too surprised if we got a warmer than average month tbh. 

[lassie23]

the BBC weather presenter just said the S word on national television

[damianslaw]

Await ECM, GFS and UKMO going fir a direct arctic northerly Easter Monday, most northerly alignment you can have with a major rise of pressure over Greenland, certainly would bring risk of snow to low lying parts in the north at least. 

GFS locks in the cold thereafter further shots of wintry precipitation.

Let's see what ECM does, the timeframes are moving into the reliable now.. less room for corrections. The high hanging around to our west is helping to store up the build and depth of cold over Greenland, a release our way will bring significant cold.

[stodge]

Evening all

Pending ECM's 12z, it looks like a significant cold blast from the north incoming at T+120 so while much of Easter will be reasonable for most, Monday looks potentially unseasonably cold.

One of the interesting developments from the evening modelling is as the HP eases slightly west, a new LP is able to form to the west and south west of Iceland and swing SE towards the British Isles re-enforcing the N'ly flow later next week.

The 12Z GFS OP is remarkably chilly for most of the run as is Control with the HP remaining in mid-Atlantic and heights persisting over Greenland keeping us on the cold side of the trough for several days and towards mid month.

[The Northern Ramper]

1 hour ago, minus10 said:

Yes the gfs 12z lines up at least 3 more organised sleet/snow chances for some in between the sunshine and wintry showers. 

I think the UKMO T120 presents the almost perfect northerly Mike....

 

Am I wrong to be thinking polar low?

[Frigid]

GFS, GEM and ICON, are all renewing the northerly around the 8th April and keeping it cold throughout. If that GFS 12Z came off I wouldn't be surprised if April came in cooler than March and possibly the coolest April since 1989 in the CET zone, if the second half keeps it cool/average. 

[Mike Poole]

ECM T120 follows suit with the other models.  It is the full on northerly blast, let’s see how long it lasts in subsequent frames!

The slight NNNW angle might actually bring in further cold air?

[Griff]

ECM Monday 120hrs

Edit... What Mike said, innit, ^

Edited March 31, 2021 by Griff

[Griff]

And 144

[Mike Poole]

ECM T144

The cold keeps coming...

[The Northern Ramper]

Winter model watching at its finest, in April

[Griff]

Just now, Ramp said:

Winter model watching at its finest, in April

Yes, where's @Battleground Snowand @MATTWOLVESetc? 

[Griff]

Clinging on at 168 too

[minus10]

20 minutes ago, Ramp said:

Am I wrong to be thinking polar low?

With the potency of this northerly polar lows have got to be a real risk..

[Mike Poole]

Just now, Griff said:

Clinging on at 168 too

Yep, and looking at the pressure chart, could be more cold coming:

Looks even sharper. 

[minus10]

6 minutes ago, Griff said:

Yes, where's @Battleground Snowand @MATTWOLVESetc? 

And @Nick Sussex ?

[Mike Poole]

1 minute ago, minus10 said:

With the potency of this northerly polar lows have got to be a real risk..

Well they would be in the depths of winter, but I’m not sure in April - doesn’t SSTs play a role in these phenomena?  

It looks like SSTs are generally above average to the north anyway, so I don’t see polar lows.

[Griff]

Either going West or a lull before the reload  

Edited March 31, 2021 by Griff

[Griff]

7 minutes ago, Griff said:

Either going West or a lull before the reload  

Tough call, a long way out and likely to change but "potential"

Edited March 31, 2021 by Griff

[The Northern Ramper]

7 minutes ago, Mike Poole said:

Well they would be in the depths of winter, but I’m not sure in April - doesn’t SSTs play a role in these phenomena?  

It looks like SSTs are generally above average to the north anyway, so I don’t see polar lows.

I don’t have the knowledge in this field, mainly due to them being as rare as hens teeth. 

[Griff]

ECM says next week will be cold then

[snowlessayr]

14 minutes ago, Mike Poole said:

Well they would be in the depths of winter, but I’m not sure in April - doesn’t SSTs play a role in these phenomena?  

It looks like SSTs are generally above average to the north anyway, so I don’t see polar lows.

My understanding is that you need the warm waters as that is what forms these polar lows as it is the temperature gradient that fuels the low. the warmer they are the better is my understanding for polar lows. Unless I have it totally wrong which I may have. 

[knocker]

8 minutes ago, Ramp said:

I don’t have the knowledge in this field, mainly due to them being as rare as hens teeth. 

Polar lows are complicated beasts. This might be useful

http://www.eumetrain.org/satmanu/CMs/PL/index.htm

[Griff]

3 minutes ago, Griff said:

ECM says next week will be cold then

For flips sake, I should have just checked the GEM