Model Output Discussion - 16th Jan 12z onwards - Smile While You Post!

[gottolovethisweather]

Too many one liners.

 

Any chance of some quality over quantity postings in here please or I might ask Paul to shut the thread for a wee while, a bit drastic but you never know it might help.    How was school today kids. 

 

 

Please use the report function, think before you post and also you have the option to use PM for contacting an individual over his or her posts, rather than clutter up the thread with non related discussion. 

 

Thanks

Edited January 16, 2015 by gottolovethisweather

[SMU]

ECM 96

 

First band of atlantic driven weather will bring rather a weak band of snow across the west ( possibly into the south )

Crucially lower heights than the UKMO -

 

http://www.meteociel.fr/modeles/ecmwf/runs/2015011612/ECH1-96.GIF?16-0

 

ECM 120

 

http://www.meteociel.fr/modeles/ecmwf/runs/2015011612/ECH1-120.GIF?16-0

 

 

Not to bad- better than the UKMO, snow moving through turning to rain in the South & SW, decent for the NE & Scotty !!

 

Look purely at the 850s **MAYBE** just maybe the snow will hold for longer as the -5 lines is still south of the M4 !!!! everyones favourite location...

http://www.meteociel.fr/modeles/ecmwf/runs/2015011612/ECU0-120.GIF?16-0
S

 

HI WIB yes to all of the above but no time to explain all that at work- so just went with how it manifests which is a flatter azores high

Edited January 16, 2015 by Steve Murr

[Cheshire Freeze]

ECM is very similar to the UKMO output earlier at 120 hrs but there is some good news....we can see the 850s and they're at or around -5. Should be good enough to support a snowfall as BA suggested earlier.

[chionomaniac]

I'd rather spend my own time looking at the models rather than removing personal digs at each other. I suggest some of you walk away from your computers for a bit, or timeouts will be enforced.

Thanks.

[Snowy L]

ECM looking good for a snow event I think. I can't tell because the charts are 24 hours apart and there is no precipitation chart, but it looks like a shortwave on the leading edge of the atlantic low moves across the UK from NW to SE. The 850s are good for most places so could potentially be a good snow event?

 

http://www.wetterzentrale.de/pics/Recm961.gif

 

I'm guessing the precip chart for this would show precipitation on the east coast?

Edited January 16, 2015 by Snowy L

[Kentish Snowman in Yorks]

ECM is very similar to the UKMO output earlier at 120 hrs but there is some good news....we can see the 850s and they're at or around -5. Should be good enough to support a snowfall as BA suggested earlier.

Indeed, I might go as far as to say that ECM 120 chart is the best yet for widespread snow from that slider.

With the surface cold already in place some areas could take a pasting!

[Mark Bayley]

ECM looking good for a snow event I think. I can't tell because the charts are 24 hours apart and there is no precipitation chart, but it looks like a shortwave on the leading edge of the atlantic low moves across the UK from NW to SE. The 850s are good for most places so could potentially be a good snow event?

 

http://www.wetterzentrale.de/pics/Recm961.gif

 

Agreed, i quite like the ECM so far. Cold enough to support snow for most regions, although as alluded too by Steve, a little more marginal in the South and West, but even here would see snow for a time. Precipitation charts should be available here in a few hours > http://en.vedur.is/weather/forecasts/atlantic/#type=prec

 

Another snow (to sleet/rain) event at T168, although marginal 

Edited January 16, 2015 by Mark Bayley

[Team Jo]

I feel like a stuck record, but please hit report if you feel a post doesn't belong in here or isn't appropriate. Please don't reply to said post commenting about how you feel it's inappropriate, like I said this morning, we are a small team and this creates loads more work....

So.. Report if you don't like it! we will get to deal with it faster.

[Dancerwithwings]

To be fair that's a good run so far from the ecm! Looks very snowy for much of the uk!! Anything that's not like the ukmo i will take! ! Ecm could just have saved the day and the nerves!!

This would bring a very snowy outlook come 96h & 850s are at -6 to -7 so most PPN would be of SNOW

 

[The Enforcer]

ECM is very similar to the UKMO output earlier at 120 hrs but there is some good news....we can see the 850s and they're at or around -5. Should be good enough to support a snowfall as BA suggested earlier.

I am struggling to follow this presently, because the links on the first post of this thread have not updated? I can't see the 12z's for the UKMO, GEM or now ECM. Also, what's the rationale for the UKMO model not containing 850 info, which appears fairly standard for most models and would be helpful in drawing comparisons? And while I'm in inquisitorial mode, why aren't the DAM lines shown on the T+0 and T+24 Fax Charts? Sorry for so many questions, hope they are sufficiently model related not to be deleted.

 

EDIT - UKMO just updated.

Edited January 16, 2015 by The Enforcer

[igloo]

Indeed, I might go as far as to say that ECM 120 chart is the best yet for widespread snow from that slider.

With the surface cold already in place some areas could take a pasting!al 

yes most of the country should get some but its short lived and followed with the more normal type rain

Edited January 16, 2015 by igloo

[warrenb]

Slider followed by slider at 168, but little to far east.

[Nick F]

While the ECMWF rolls out, here’s a rundown of what’s happening over the next 3-4 days.

 

Friday night/Saturday

 

A trough/occlusion tracks SE across Ireland and the southern UK overnight and Saturday morning. so we are likely to see the sleet and snow showers already across the NW move southeast across NW England, Wales, Midlands and West Country by 6am Saturday, snow accumulating over higher ground, but also to lower levels too in places with heavier bursts. The band of sleet and snow showers reaching SE England and E Anglia by mid-morning, though perhaps falling mostly as rain/sleet across southern coastal counties and London area with the air having warmed up by the time the showers arrive. Further snow showers for northern Britain into the afternoon – particularly N Ireland, W Scotland and NW England, drier and sunnier afternoon across southern areas, though some showers spreading in across SW England and Wales in the afternoon, mostly rain at lower levels, but falling as snow over Welsh hills.

 

Sunday.

 

Now this is proving a bit of a headache towards the far south, an area of low pressure moving in across the Bay of Biscay spreads a ‘plume’ of moisture north towards southern England, you can see the northern extent of the plume by the warm front toward the SW. 12z Euro4, HIRLAM and GFS bring an area of rain in across southern counties of England on Sunday morning, turning to snow across the SW Moors and perhaps further east across higher parts of central S and SE England – what’s not so clear is, with increasingly cold air spreading south and evaporative cooling, whether the rain will turn to snow at lower levels too – a possibility that will be down to nowcasting! GFS, Euro4 and HIRLAM clear the rain/sleet/snow  by early Sun afternoon.

 

Further north, more clear cut, cold with sunny spells, but perhaps some bands of sleet and snow showers spreading south through the day, giving some accumulations in places – particularly over high ground.

 

Early next week

 

Monday’s looking mostly dry and bright or sunny and quite cold (temps 1-3C generally, 0C or below over the snow fields in the north), but a shallow low over the North Sea could bring sleet and snow showers towards eastern coastal counties.

 

Tuesday, confidence drops as we see an area of low pressure near Iceland and a shortwave upper trough moving SE aloft pushing an Atlantic frontal system in across the west, which stalls against the cold block. Lack of confidence revolves around how the models push in this frontal system and what falls out the sky where. To complicate issues, GFS forms a low over the SW before dropping S across western France. But general theme from GFS and other models is it pushes rain in from the west on Tuesday - which turns to snow across Scotland and N England, for Wales and SW England, it suggests more likely rain/sleet at lower levels. Extent east uncerain for now.

 

Mid-week and beyond, a difficult call, less cold air trying to push in from the west and cold stagnant air across the UK under a slack flow pattern is always going to cause the models problems. Model uncertainties over how far east to place upper trough extending down from Iceland/greenland by then. So wouldn’t want hazard a guess to where snow chances will be by then, suffice to say the cold will probably hang on longer than models suggest.

Edited January 16, 2015 by Nick F

[SMU]

So JMAs Take-

 

http://www.meteociel.fr/modeles/jma/runs/2015011612/J120-21.GIF?16-12

 

The tracks have certainly moved East / NE today moving the sweet spot closer to the NE of england where stalled out snow could develop-

 

From now on in it will really be IMBY related as to where the track goes-

 

Relating to the ECM 120-168 - lots of snow in the North sea.

We need it to bend back about 100 -200 miles which is certainly feesable!!

 

S

[Mucka]

ECM with the second slider, Scandi ridge and Easterly to follow?

As mentioned previously we don't need big corrections back West to stay on the cold side.

 

PV just won't relent. Probably too fast and flat upstream this run.

 

Edited January 16, 2015 by Mucka

[warrenb]

Well I didn't see that 192 chart coming.

[TSNWK]

Well I didn't see that 192 chart coming.

Nice surprise or not?

[warrenb]

Well not sure, the second slider seems to zip through, and we are left in a bit of no mans land.

[SMU]

2 pretty consistent runs from the ECM ( track headaches removed )

 

slider after slider, however the cold building to the East is the biggest retaining news...

 

http://www.meteociel.fr/modeles/ecmwf/runs/2015011612/ECH1-216.GIF?16-0

 

A slight nudge west ( circa 100 -200 miles & its a uk deep snowfest)

 

S

[Backtrack]

This would bring a very snowy outlook come 96h & 850s are at -6 to -7 so most PPN would be of SNOW

 

 

Look at that tasty low sat out in the Irish Sea. Wales and the North West would get absolutely hammered, with many showers penetrating further southwards too.

[Mark Neal.]

2 pretty consistent runs from the ECM ( track headaches removed )

 

slider after slider, however the cold building to the East is the biggest retaining news...

 

http://www.meteociel.fr/modeles/ecmwf/runs/2015011612/ECH1-216.GIF?16-0

 

A slight nudge west ( circa 100 -200 miles & its a uk deep snowfest)

 

S

How likely do we think that this 100-200mile nudge west is to occur? Any serious hope?!

[SMU]

How likely do we think that this 100-200mile nudge west is to occur? Any serious hope?!

 

You cannot put any quantifable numbers on that, could flatten east could nudge west,

But at least were in the game.....

 

Here is the ECM DET 240 - rounding off perhaps a nerve settling run. ECM is the midpoint of the tracks at day 5 ( 120 )

http://www.meteociel.fr/modeles/ecmwf/runs/2015011612/ECH1-240.GIF?16-0

 

PLENTY OF TIME FOR CORRECTIONS YET...

S

[craigore]

2 pretty consistent runs from the ECM ( track headaches removed )

 

slider after slider, however the cold building to the East is the biggest retaining news...

 

http://www.meteociel.fr/modeles/ecmwf/runs/2015011612/ECH1-216.GIF?16-0

 

A slight nudge west ( circa 100 -200 miles & its a uk deep snowfest)

 

S

I agree looking at that chart it all seems to be happening in mainland Europe and once again the u.k is in no mans land...

[igloo]

the ECM wants to give us our first s westerlies this season on the later parts of the run did ian not mention a few days back that the ECM 32 had us in either a west or sw pattern in february it may well be starting to pick this signal up 

 

[TSNWK]

How likely do we think that this 100-200mile nudge west is to occur? Any serious hope?!

Well past performance in similar situations is for all to drift east.. So it has to be an outside bet.. But we are in game so Not 100/1 outsider more like 10/1 I would punt.