Model output discussion - 20th Feb onwards

[Weather-history]

Is UKMO bringing that low closer with each run?

[feb1991blizzard]

1 minute ago, Banbury said:

Crap uppers??

 

What an odd comment

If you really class the -6c isotherm as something great then you are easily pleased.

[karlos1983]

Just now, mulzy said:

A cool largely dry spell with night-time frosts is now to be expected according to the latest NWP.  There is a risk of some precipitation in the west on Friday which may turn wintry in places (UKMO day 4 chart is more suggestive of this).

Friday night into Saturday would be of interest to me. Wish we got to see the Precip, not to worried about 850's.

[Harsh Climate]

Nice charts If you live in the east and are happy with just the sight of light/moderate sleet or snow showers blowing in off the north sea with no settling.

But for appreciable snowfall away from the north yorkshire moors we need at very least that -10 850 dam line crossing the UK. In march 2013 it was generally -12s on that day of heavy snowfall. I'm sorry but uppers of minus 6/7 just aren't going to cut the mustard at this time of year for convective snow showers. And I'm not just talking about the temperature being cold enough for settling snow, without double digit uppers the north sea will struggle to generate appreciable snow showers.

But this upcoming cold spell still is of interest, I think our greatest chance of snow will come from energy trying to spill in from the west into our dry cold air, uppers of -6/-7 in this situation should suffice!

Edited February 22, 2016 by Harsh Climate

[Mapantz]

I have to agree on the convective front. There's nothing remotely convective showing up at that particular time frame. I don't know whether its because it is a little far out to be questioning those parameters or not..

Taking it as it shows it now, I suspect it would be little more than snow grains and the odd wintry shower here and there. The humidity levels look pretty low as well.

It's pretty pointless speculation anyway, I just thought i'd post my thoughts on it.

 

[Gowon]

Just now, Banbury said:

Crap uppers??

 

What an odd comment

its crap trust me.. it will feel cold but to generate proper snow showers were going to need lower than -5 uppers. 

[feb1991blizzard]

1 minute ago, Weather-history said:

Is UKMO bringing that low closer with each run?

Yes, I am far more interested in what might evolve from these type of setups as the Easterly just wont cut it, the second slider might just be about to deliver an almighty blizzard on the GFS but obviously too far out.

[winterof79]

2 minutes ago, Vivian said:

its crap trust me.. it will feel cold but to generate proper snow showers were going to need lower than -5 uppers. 

We're getting higher uppers wth each post.We started at -8 you're at -5 now.Clarify with a chart from Saturday please.I posted one with -8/7 uppers.

 

[Biggin]

50 minutes ago, feb1991blizzard said:

Precip charts 5 days away ? lol

[Banbury]

7 minutes ago, feb1991blizzard said:

If you really class the -6c isotherm as something great then you are easily pleased.

Never spoil a good story with the facts eh

[winterof79]

5 minutes ago, feb1991blizzard said:

Yes, I am far more interested in what might evolve from these type of setups as the Easterly just wont cut it, the second slider might just be about to deliver an almighty blizzard on the GFS but obviously too far out.

As with nearly every snow potential it won't cut it for all.Tell North Yorkshire and the east it won't though.

[feb1991blizzard]

3 minutes ago, Biggin said:

Precip charts 5 days away ? lol

Ok then - I actually think that pressure chart with similar uppers and 500mb profile is very likely to verify so we will see what showers we get, what do you think will be showing on the graphics on the BBC forecasts on Friday night? if its any more than a few white dots on the East coast then I will walk down the high street stark naked.

Edited February 22, 2016 by feb1991blizzard

[karlos1983]

-7 Uppers it would appear

Would feel pretty unpleasant I might add

 

Edited February 22, 2016 by karlos1983

[johnholmes]

11 minutes ago, Vivian said:

its crap trust me.. it will feel cold but to generate proper snow showers were going to need lower than -5 uppers. 

not true -5C depending on what the value is at 700mb and at the surface can quite easily give snow showers.

[MR EXTREMES]

I agree looking at the uppers being mixed out by warmer air from the med as nick Sussex suggested earlier.

we need the low to move further se into the med.

ive not said I want an easterly anyway because I know the uppers wont be good enough that's why I suggested northeasterly or arctic northerly.

and maybe I'm wrong then about -6 -7 uppers being good enough for snowfall.

so to keep things flowing nicely in the forum id like to apoligise

[Essex snowman]

Omg your all getting toys out of Pram calm down go with the flow if like me I get to see some snow flakes then lovely if not never mind I won't get depressed about what charts are showing for 5 days away 

[winterof79]

2 minutes ago, feb1991blizzard said:

Ok then - I actually think that pressure chart with similar uppers and 500mb profile is very likely to verify so we will see what showers we get, what do you think will be showing on the graphics on the BBC forecasts on Friday night? if its any more than a few white dots on the East coast then I will walk down the high street stark naked.

Brave man with -8 uppers and a stiff Easterly

[feb1991blizzard]

Just now, johnholmes said:

not true -5C depending on what the value is at 700mb and at the surface can quite easily give snow showers.

But John on that chart it looks to me (by looking at 500mb) that the mid level lapse rates wouldn't be steep enough for anything significant, could you please confirm or deny whether the chart I posted above would give more than a few light showers.

[Gowon]

10 minutes ago, johnholmes said:

not true -5C depending on what the value is at 700mb and at the surface can quite easily give snow showers.

Thanks John..  I don't think it's going to be enough though but we'll see.

Edited February 22, 2016 by Vivian

[NorthYorksWeather]

Looking at the GFS, uppers of between -6c and -8c are forecast along the East Coast this coming weekend. Living in the NE I keep taps on the conditions in which my area experience convective  snowfalls, last Sunday/Monday we had uppers of around -7/-8c in which snow fell to lower levels even during the day, of course settling was a different matter and this only occurred either overnight or during the heaviest showers. For my area General rule of thumb is -5c for snow falling above 200m and -7c for low levels (my elevation). This is by no means a forecast as there are many more variables but my input after recording snow here near the east coast for a good few years. 

Edited February 22, 2016 by vizzy2004

[chris55]

58 minutes ago, karlos1983 said:

Almost a nice snow event for the Southwest at +96 on the GFS

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=96&mode=0

This caught my attention on the 00z ECM this morning.

Risk of that front edging into the west is certainly a possibility!

This mornings ECM at 96

And as you say GFS 12z  follows suite and develops the system into Friday! The front doesn't make that much progress into the UK but it's literally a few hundred miles, so way to early to determine eventual outcome.

As Ian mentioned above Friday is definitely a day to watch if your in the west!

 

 

[Jason M]

Tbh, it doesn't look anything special to me at the moment. I think those expecting ice days and deep snow are going to be disappointed.

I thought Steve Murr nailed it earlier today when he said there was a good chance of falling snow at sea level, but maybe not settling. IMHO we are looking at a bog standard UK cold spell based on current output. Basically, what Fergie seemed to allude to earlier.

It could change, but after such a warm winter (both in NW Europe and in the northern hemisphere more generally) I simply can't see anything severe on the horizon. Probably best case scenario is an area of snow moving northwest out of France associated with low pressure to our SE. Maybe we could get a covering from something like that.

In any case, no point in getting wound up about it. We will find out who is right or wrong over the next week or so.

 

 

[throwoff]

That GFS snow risk chart is amazing, it literally touches the edge of the entire east coast!

[bigdog1]

Why are people arguing over charts that are five days away there will be lots of upgrades and downgrades before we get there 

[Liam J]

Not seeing any charts suggesting a proper convective easterly. Ideally you want to see 850's around -10c or lower and deeper cold 500mb temps for the instability. 

 

Easterly wind off relatively warm North Sea SST's with 850's of only -6/-7c keeping eastern areas above freezing. 

Anyway we're talking 5/6 days away so plenty of time for upgrades. 

 

The coldest air moving south midweek with -10c 850's into the north.