Model Output Discussion

[johnholmes]

will snow for me?

Monday or any other day?

see pdf file below

go on try it it does work but remember ONLY if the charts are showing PRECIPITATION and also remember trying to predict even rain in summer let alone will it snow in winter more than 24 hours ahead has more problems than the mods have trying to keep this thread in some semblance of order!

will it snow 7 feb 2010.pdf

[lorenzo]

Think the confusion is between height charts and thickness charts relating to the 528 DAM line.

http://www.weatheron...M=0&PANEL=0&WMO=

Am pretty much a novice so someone correct me if I am wrong here..

[johnholmes]

Think the confusion is between height charts and thickness charts relating to the 528 DAM line.

http://www.weatheron...M=0&PANEL=0&WMO=

Am pretty much a novice so someone correct me if I am wrong here..

you could be right about that although I have not investigated the claims this morning

[SussexmarkyMark]

Think the confusion is between height charts and thickness charts relating to the 528 DAM line.

http://www.weatheron...M=0&PANEL=0&WMO=

Am pretty much a novice so someone correct me if I am wrong here..

Thanks for that. You may well be right, but I'm not an expert either.

Edited February 7, 2010 by SussexmarkyMark

[Bobby]

As I see it from the models for next week...

First half: Cold air filters in from the NE bringing occasional light rain/sleet/snow showers into E and more so SE England. Mainly dry elsewhere with some overnight frosts.

Second half: Showers becoming more of snow and potentially becoming heavier and more widespread later into the week although disruptive snowfall unlikely.

Hints then next week of a more potent cold and snowy outbreak as high pressure migrates to greenland.

Edited February 7, 2010 by Barb-

[bluearmy]

http://www.meteociel.fr/modeles/gfse_cartes.php?ech=6&code=0&mode=3

this ones easier to make sense of

no issue with thicknesses

no issue with snowfall through the week. as with the last cold spell, some will get some will not. doubt we'll see totals we had last time though.

[TEITS]

FYI I have spent quite a bit of time looking at the charts this morning. I have looked again at the same time scale as the chart that you have produced (ie the GFS +48 chart) and the one I am looking at does not show the 528 DAM over the UK. If the chart is wrong, then so-be-it, but I can only look at the charts that are being shown. So perhaps it would have been politer to ask which charts I was looking at without the rude comment to finish your post ?

http://www.weatheron...=0&ARCHIV=0&WMO=

I see what you mean, apologies for that.

These are the charts you should be looking at.

http://expert.weatheronline.co.uk/daten/proficharts/en/2010/02/07/basis06/euro/tpps/10020906_0706.gif

http://www.wetterzentrale.de/pics/Rtavn483.png

As you can see these agree with the UKMO fax chart at +48 that I posted with regards to the 528 line.

With regards to the Met O/BBC forecast. What im saying is these forecasts tie in nicely with my summaries of the model output for the last few days.

Back to the model and output and you can see why the BBC mentioned more prolonged snow for Wed. A trough is going to move S and then push SW. The GFs agrees with this.

http://www.wetterzentrale.de/pics/brack2.gif

http://www.wetterzentrale.de/pics/Rtavn844.png

!

Edited February 7, 2010 by THE EYE IN THE SKY

[Methuselah]

will snow for me?

Monday or any other day?

see pdf file below

go on try it it does work but remember ONLY if the charts are showing PRECIPITATION and also remember trying to predict even rain in summer let alone will it snow in winter more than 24 hours ahead has more problems than the mods have trying to keep this thread in some semblance of order!

will it snow 7 feb 2010.pdf

Hear! Hear! All this predicting Thames, Sneckie, Hull, Embra (or any other) snowstreamers ten-days in advance really is getting somewhat annoying...the synoptics change with each-and-every run on each-and-every model...Yes, it's looking cold and, yes, snow will feature. But, IMO, that's all we can say the now???

And, yes - it might all go the way of the pear??? Are we forgetting last-year's 'nailed-on' certainty that never was?

[SussexmarkyMark]

I see what you mean, apologies for that.

These are the charts you should be looking at.

http://expert.weathe...020906_0706.gif

http://www.wetterzen...cs/Rtavn483.png

Thanks for clarifying.

Edited February 7, 2010 by SussexmarkyMark

[evansc5487]

Sems the really cold air keps getting put back. Now its next wekend before the fun starts

In the meantime for central and western regions, nothing too much to get excited about

Same old story, how many times have we heard 'the cold keeps getting pushed back' and 'its been put back a few days'. Very frustrating, me thinks this potent cold is just not going to make it right across the UK, just flirting with the east of the country once again.

[bluearmy]

the models appear to be keen to retrogress the high nw quite quickly once it is able to move in that direction (WAA north west atlantic and trough ejecting ne out of greenland ). this is showing in fi GFS runs as allowing the atlantic in around the 18/20th feb. note that the ecm ens also go less cold by this timeframe. i'm not convinced that this will be such a quick evolution and we may enjoy longer periods with excellent potential for snowfall than currently looks to be the case. at the moment, the ens go for a 9 day period below -5c in the se. i think it may well be longer or at least, a continental feed as we approach any breakdown may make uppers between -5 and 0c less relevant than usual.

i posted midweek that i thought there was the opportunity for maybe 3 snow events out of this upcoming spell and i see nothing several days later to make me think differently.

[TEITS]

Same old story, how many times have we heard 'the cold keeps getting pushed back' and 'its been put back a few days'. Very frustrating, me thinks this potent cold is just not going to make it right across the UK, just flirting with the east of the country once again.

Im not sure I agree.

Lets use Dublin as an example which is obviously the last stop of the E,ly train.

http://cirrus.netweather.tv/ensimages/ens.20100207/06/t850Dublin.png

Even here the mean drops to around -8C.

Devon is even colder.

http://cirrus.netweather.tv/ensimages/ens.20100207/06/t850Devon.png

[Mark Parsons]

Same old story, how many times have we heard 'the cold keeps getting pushed back' and 'its been put back a few days'. Very frustrating, me thinks this potent cold is just not going to make it right across the UK, just flirting with the east of the country once again.

This all seems similar to the pattern leading up to the last cold spell so no need to be to dispondant, it will come in good time and the models will probably show this over the coming week.

[Backtrack]

Well look at the chart, the 0s in the East (where the precip is). That's above freezing.

Here is the GFS precip chart for the same time:

As you can see, mainly rain/sleet.

I'm talking about FI, next weekend and after. This ECM chart for example:

http://www.meteociel...M1-216.GIF?06-0

How is 0c above freezing?

0c is freezing, and any precip will fall as snow due to the colder 850's!

[Harsh Climate]

How is 0c above freezing?

0c is freezing, and any precip will fall as snow due to the colder 850's!

Not necessarily, during the last dec cold spell it rained at -1C due to a sector of milder air that moved in from the north sea.... The air predicted to move in from the east isnt exceptionally cold neither, maybe with the exception of kent, who will almost certainly fair best out of this coming cold spell....

Edited February 7, 2010 by Jed Bickerdike

[Bobby]

How is 0c above freezing?

0c is freezing, and any precip will fall as snow due to the colder 850's!

Look at the legend, the lighter colour is the 0-2c isotherm so anything in that area is freezing or above.

[Snowyowl9]

As I see it from the models for next week...

First half: Cold air filters in from the NE bringing occasional light rain/sleet/snow showers into E and more so SE England. Mainly dry elsewhere with some overnight frosts.

Second half: Showers becoming more of snow and potentially becoming heavier and more widespread later into the week although disruptive snowfall unlikely.

Hints then next week of a more potent cold and snowy outbreak as high pressure migrates to greenland.

It`s going to cold all week starting today,not quite cold enough for snow today more like the last day with drizzle,tonight geting more wintry.

Country tracks forecast was quite a surprise more snow that I expected,be it light in the west but that`ll do for me with charts like this. :lol:

The high close by atlantic is put to sleep.

http://wzkarten.de/pics/brack1a.gif

Edited February 7, 2010 by Snowyowl9

[J10]

Which charts are you looking at that suggest widespread snow and potent cold, I wonder? I've had a look through the output for the main three models this morning and they all seem to keep the very cold air to the south and east of us, with the 528 DAM line barely reaching the UK before +144, whereas a couple of days ago the 512 DAM line was making an appearance over SE England. The HP seems to be much more centred over the UK through the next four or five days, keeping the colder air over mainland Europe. Only once we get towards next weekend and beyond does any potent cold arrive in the UK which, as we all know from the last week, is well beyond the reliable time-frame.

Sub 528 air and indeed sub and more importantly 129 air is over the UK within 24 hours according to the latest GFS charts.

[Iceberg]

Look at the legend, the lighter colour is the 0-2c isotherm so anything in that area is freezing or above.

That legend is mm of precip surely. ?

[Bobby]

That legend is mm of precip surely. ?

I mean the dew point chart:

http://www.meteociel.com/modeles_gfs/run/78-101.GIF?07-6

[Iceberg]

I mean the dew point chart:

http://www.meteociel.com/modeles_gfs/run/78-101.GIF?07-6

Sorry not trying to be perdantic, but that shows nothing above 0C for the UK.

I know the shading is for 0-2 but if it where 1 or 2, then it would show 1 or 2 and not 0.

[nick sussex]

Good news the MJO has slowed down and is slowly creeping towards phase 8.

http://www.cawcr.gov.au/bmrc/clfor/cfstaff/matw/maproom/RMM/phase.Last40days.html

We don't want it to move too quickly though phase 7 and 8.

[Bobby]

Sorry not trying to be perdantic, but that shows nothing above 0C for the UK.

I know the shading is for 0-2 but if it where 1 or 2, then it would show 1 or 2 and not 0.

Well if you want to be pedantic, even 0.000000000000000000000000000000001c is above 0c (and above freezing). So unless there's a place there that's 0.0c to infinity exactly, everywhere there is above 0c (freezing).

(in that 0-2c isotherm)

[Methuselah]

Maybe a tad OT...But, remember this when you accuse peeps of ramping-up the models???

[damianslaw]

Its a classic slow evolution to deep cold uppers as we head through this week. Initially we will have a light easterly flow favouring some snow showers in eastern parts, as we head through the week a stronger NE/E flow will develop pulling in colder uppers and increasing chances of more widespread snow in the east perhaps filtering into central parts and maybe western areas by the weekend. During the weekend retrogression of heights to Greenland and then bingo we are in firm upper cold territory with chance of significant widespread snowfalls anywhere courtesy of troughs from the north thanks to the scandi trough and lowering heights over Scandi, later on chance of southerly tracking lows/undercutting etc...

The period 13th-20th Feb looks to be when we see the significant cold weather and opportunities for widespread significant snowfall, the coming week whilst cold with some sharp frosts in the west and some snow showers in the east is going to look tame compared to the following week. I sound like a broken record inr ecent days but all signs have been for strong heights to ridge down from Greenland as we head towards middle of Feb - watch the models ontinue to show this synpotical evolution in the coming days. Wouldn't it be great to see a polar low before the winter is out.. mmm maybe we will see such a one..