Model output discussion - mid-winter

[karlos1983]

Just now, Snowmadsam said:

Again, 100 miles south and we could all do well on that, needs watching. Evaporative cooling COULD happen but precipitation would have to be intense...

UKMO shows no sign of said low...

It’s entering Benelux at 144

[Methuselah]

What do we reckon here, then? Overnight rain, sleet or snow - followed by a tricky drive into work?

[karyo]

Good to see that the low is less deep on the 12z. It is still there though so it needs to be monitored in future runs. The UKMO looks better than the gfs at the same timeframe as the feature is shallower.

[mulzy]

Hmmm, GFS looks very progressive after day 6.  Worrying trend...

 

Edited January 12, 2018 by mulzy

[Snowmadsam]

4 minutes ago, karlos1983 said:

It’s entering Benelux at 144

so it is, missed that! cheers

 

[karyo]

Just now, mulzy said:

Hmmm, GFS looks very progressive after day 6.  Worrying trend...

 

Lots of shortwave activity over northeast Canada and southern tip of Greenland so difficult for a ridge to develop northwards.

[radiohead]

7 minutes ago, Snowmadsam said:

Again, 100 miles south and we could all do well on that, needs watching. Evaporative cooling COULD happen but precipitation would have to be intense...

UKMO shows no sign of said low...

Here is the low at T144.

[Maz]

16 minutes ago, Ali1977 said:

GFS always seems to model a band of snow in the central belt - right accross to the East from Manchester , through Sheffield area accross to Grimsby. I wonder why!!

Wind just north of west sets up a convergence zone (North Wales mountains help to distort the flow), leading to organised band of showers in southern parts of NW England, sometimes across Pennines.  Often gives Manchester its famously grey, wet days.  Maybe this time it could be less grey and more white...

[MR EXTREMES]

Impressively cold northern hemisphere

[❄️❄️❄️❄️❄️❄️❄️❄️❄️]

[ukpaul]

2 minutes ago, karyo said:

Lots of shortwave activity over northeast Canada and southern tip of Greenland so difficult for a ridge to develop northwards.

This could even form into another runner and the 850s are still frigid by that time (-6 to -8).

A chance to savour Northern Europe covered by those.

[karyo]

By next Friday winds turn more westerly. Still cold but more systems coming from the Atlantic.

 

[terrier]

Don’t forget guys gfs tends to over do the precipitation charts. Think it’s futile to be looking at any snow depth charts at moment for next week. They can even be wrong at t48. Still think this away from elevation will be cold wet sleety mix. But maybe if your 1000ft above sea level you should do ok. 

[johnholmes]

36 minutes ago, karlos1983 said:

I don’t really go along with that, I think the more we learn about the drivers that ultimately decide what whether we may or may not have, the better. But i just don’t think a 3 month view on temps against average is particularly useful for deterring for example how cold February might be.

Of course we have to remember that they are issued for the general public, but for those in commerce and industry who also take more detailed forecasts which we do not see.

I would suggest you have a look at the Met O website, and even consider sending an e mail to politely ask how this data is used.

[karyo]

1 minute ago, ukpaul said:

This could even form into another runner and the 850s are still frigid by that time (-6 to -8).

A chance to savour Northern Europe covered by those.

It is impressive but if the ridge doesn't develop the pattern will flatter too much.

[Snowmadsam]

UKMO sadly, slightly takes away the -4 isotherm at +144

All worth watching! (if any of this is wrong, please tell me!) still very much learning!

[andymusic]

2 minutes ago, karyo said:

By next Friday winds turn more westerly. Still cold but more systems coming from the Atlantic.

 

yep bumping into cold uppers and dumping more snow

[Thunderywintrysnow]

2 minutes ago, mulzy said:

Hmmm, GFS looks very progressive after day 6.  Worrying trend...

 

Never fear runner runner is here.

[Methuselah]

Another slider in the offing?

[MR EXTREMES]

8 minutes ago, karyo said:

Lots of shortwave activity over northeast Canada and southern tip of Greenland so difficult for a ridge to develop northwards.

Ridge will come either out from the north or retrogression from Scandinavia through to Iceland.

But agree not likely to see Azores ridge north right up into Greenland.

But plenty of options on the table.

Edited January 12, 2018 by MR EXTREMES

[andymusic]

and more snow

[MR EXTREMES]

5 minutes ago, Ed Stone said:

Another slider in the offing?

As long as it's not giving us the runner around the slider channel runner is all part of the fun.

And split vortex......

And the retrogression of the Scandinavia heights slightly north of Iceland and merging with shallow heights north of Greenland.

 

Edited January 12, 2018 by MR EXTREMES

[mulzy]

3 minutes ago, Ed Stone said:

Another slider in the offing?

Yet another M4 north event. Arghhhhhhhhhhhhhhhhhhh!!

[andymusic]

and ummmmmmmmmmmmmmm oh yeah more snow

[Methuselah]

And another one for the Friends of The M4!