Winter Model Discussion 12Z 15/02/13 onwards.

[Tamara]

No comments on the ukmo??

It is at t60. What is noticeable over this short period on the Meteocil sequence is how the cold pool generates over western Russia and Eastern Europe

[Ian Brown]

No comments on the ukmo??

It's only to T72?

[Harsh Climate]

Just like to say, this looks very light snow/light snow showers for eastern areas but some places have it for over 36 hours.

In the area under 0.2mm - 0.5mm/hour snowfall rates, over 36 hours that would = 7 - 18cm of snow. All relative though ; )

Edited February 15, 2013 by Harsh Climate

[Hammer]

UKMO clearly being modified in real time by Ian F before we see it.

Edited February 15, 2013 by Hammer

[PB22]

Given how GFS was for so long struggling to grasp the forthcoming pattern, its consistency between the 12z and 6z run is remarkable at T+162:

http://modeles.meteo...fs-0-162.png?12

http://modeles.meteo...fs-1-162.png?12

More of an Atlantic push into the southwest on this run, could bring a significant snow event if it were to verify which is unlikely at this range.

The 12z UKMO is going to be dramatic tonight and not come out!

Edited February 15, 2013 by Paul B

[Johnp]

It's only to T72?

Is it? I only have up to T60?

[No Balls Like Snow Balls]

There doesn't seem much change on the GFS upto T144, still the risk of light snow flurries / showers on the East Coast and perhaps turning up anywhere later in the week. The main interest is from the end of next week onwards with LP pushing up against the block, so obviously could be a good deal of snow for someone depending how far the LP gets. Of course this far out there may not even be LP shown this time next week, so all taken with a pinch of salt.

Edited February 15, 2013 by No balls like Snow Balls

[Spurry]

Not sure if people have missed this but for Leeds because its inland the GFS is suggesting that we could go 10 days with no precipitation (even then we are relying on a low resolution low)..

There will be a drought in March then , reservoirs will be low and we'll be praying for rain

[LomondSnowstorm]

Just like to say, this looks very light snow/light snow showers for eastern areas but some places have it for over 36 hours.

In the area under 0.2mm - 0.5mm/hour snowfall rates, over 36 hours that would = 7 - 18cm of snow. All relative though ; )

Hard to judge intensity given that that includes breaks in the showers, so it could either be a longer spell of continuous light snow or heavier stuff in the form of intermittent showers. As an average rate though that's actually fairly reasonable for convective easterlies. Not quite late November 2010 though

[latitude]

Looks like a downgrade with regard to the western movement of the cold air. On this run it dosent get passed Cornwall.

[Harsh Climate]

We know what's coming here, rain preceded by a spell of snow pushing north eastwards...

With milder air filtering in as the lack of any real cold source to the east about to hurt us.

Edited February 15, 2013 by Harsh Climate

[shaky]

What the hells happening to the ukmo!!it goes out upto 60hours and then just as it gets to the important part of the run its stops working!!somebody must be fiddling around with it!!

[Isolated Frost]

UKMO seems to have pushed everything 100mi W, as is often the case in these situations-

Cold reels in by the start of the next working week though... snow showers and sharp frosts for England, Wales, and parts of Scotland at t120.

[Cheshire Freeze]

We know what's coming here, rain preceded by a spell of snow pushing north eastwards...

Followed by mild..

How can that low push much further north when there's a big block stopping that eventuality?

[Tim Bland]

Just like to say, this looks very light snow/light snow showers for eastern areas but some places have it for over 36 hours.

In the area under 0.2mm - 0.5mm/hour snowfall rates, over 36 hours that would = 7 - 18cm of snow. All relative though ; )

Doesn't realy work like that unless the DP and temp etc are Very low. Even if they were around -10C then the sun would still melt the light snow preventing it from accumulating. Snow wise, only Kent and a few miles inland from the east coast can expect a dusting next week IMO. For widespread snow we need either a tough pushing in from the NE of a battlegraound with the atlantic pushing in from the SW

[PB22]

UKMO 12z now coming out:

T+96: http://www.meteociel...96-21.GIF?15-17

T+120: http://www.meteociel...20-21.GIF?15-17

Similar theme to this morning's run, the Scandinavian High a touch further south than the GFS has it.

Edited February 15, 2013 by Paul B

[BlueHedgehog074]

It's encouraging to have seen the GFS pretty much backtrack towards the ECMWF (the GFS 12Z seems to be heading in that direction, too) and all the other models who show blocking in a favourable place to the North/North-East with attempts of drawing in colder uppers from the East for later next week. I was starting to get worried, at one point, that the other models would have backed down with their idea of getting deeper cold further West along with their idea of more energy going South under the High-Pressure system (despite the fact the GFS seemingly under-estimates Low undercutting potential).

More changes will clearly be likely for next week with regards to how far West the block to the North-East gets. Hopefully we can continue to get a favourable angle to the placement of the high with perhaps more of a direct East, or East-North-East, wind direction to really squeeze those potent uppers as far West as possible (if it's deep cold and/or snow you are looking for). In a way, something like what the GEM shows with uppers around -10*C or colder spillin' into Eastern parts of the UK:

[Methuselah]

What the hells happening to the ukmo!!it goes out upto 60hours and then just as it gets to the important part of the run its stops working!!somebody must be fiddling around with it!!

It's collapsed under a weight of snow...

[Harsh Climate]

Hard to judge intensity given that that includes breaks in the showers, so it could either be a longer spell of continuous light snow or heavier stuff in the form of intermittent showers. As an average rate though that's actually fairly reasonable for convective easterlies. Not quite late November 2010 though

If the snow was all powder with little moisture those numbers would be easily achieved but in reality with day time temps just above freezing and not overly cold ground temps, most people would be lucky to see more than 50% of what falls settle, then build up.

[Tamara]

UKMO at t120 looks the same as this morning pretty much so far. Coldest and most unstable uppers some way still to the east

Edited February 15, 2013 by Tamara Road

[No Balls Like Snow Balls]

I like the look of the HP on the UKMO @ T96. It has a very pleasing shape.

Edited February 15, 2013 by No balls like Snow Balls

[PB22]

12z UKMO T+144:

Paving the way for an Arctic blast further down the line?

[Cheshire Freeze]

12z UKMO T+144: http://www.meteociel...44-21.GIF?15-17

Paving the way for an Arctic blast further down the line?

Yes, very nice

[Harsh Climate]

UKMO says no to initial easterly but looks like colder air pushing into eastern scandinavia/russia, so maybe better long term.

[That ECM]

GFS from t180 to t216 would give huge amounts of snow. Love the GFS! ,