Model Output Discussion

[cooling climate]

ECM keeps it very cold.

The Euro's are colder which I think is the right way to go as the GFS seems to still be upgrading the

potency of the northerly.

[phil nw.]

ECM shows the same picture at T120hrs.

http://www.wetterzen...cs/Recm1201.gif

http://www.wetterzen...cs/Rukm1201.gif

http://www.wetterzen...s/Rtavn1201.png

A decent Northerly modelled by all the output .

and continuing in the same way.

http://www.wetterzen...cs/Recm1441.gif

It looks at least a 4 day event now and a trend perhaps of keeping surface cold beyond as High pressure rises from the West.

http://www.meteociel...68&mode=1&map=0

Edited January 25, 2010 by phil n.warks.

[bluearmy]

ECM t144 uppers -8c (just) in the highlands to -5c in cornwall. thicknesses around 520dam.

maybe not quite as cold as it looks. good continuity to T168 from ecm which incidentally will upgrade as of the 12z tomorrow with a higher resolution in the op horizontal down to 16km.

Edited January 25, 2010 by bluearmy

[cooling climate]

The ECM t168 chart shows more promise to me as it enters the FI stage.

[phil nw.]

Some new fax`s out and T72hrs. shows the sypnotics on Thurs,which seems to be day 1 of the arrival of the Arctic air.

It doesn`t look much at this stage but it is in line with 12z raw output.

http://www.wetterzentrale.de/pics/Rukm721.gif

[ChartViewer]

The ECM t168 chart shows more promise to me as it enters the FI stage.

Unfortunately ECM12z is a downgrade in terms of cold uppers etc up to T144......Shame but

true............Minus 8 uppers the max we can expect to see in the reliable timeframe.

[Cecil Hogmanay Melchett]

Unfortunately ECM12z is a downgrade in terms of cold uppers etc up to T144......Shame but

true............Minus 8 uppers the max we can expect to see in the reliable timeframe.

yes thats terrible isn;t it? :(

ECM keeps it cold from Thr to Mon with some places seeing snow,imposible to know at this range where but i cant nderstand people using the smiley when we are looking at a 4 to 5 day potent cold spell.

maybe CV would prefer SW winds or somethinhg?

[MR EXTREMES]

The wind won't push the showers inland, so no, we need a NE wind if we want the showers to push anywhere near inland.

i do not agree 2004 snow band with thunder snow moved south even here in the southcoast we had an inch.

i cant see why any where in the uk get snow showers.

ukmo ecm great where it goes beyond is anyones guess its also something that held firm last december january with high in the alantic and over us was very cold under that block ive got a feeling beyond the northerly the block could sit west of us or even apon us.

as for snow it could fall anywhere how much is anyones guess aswell.

but for now anyway winter is back.

lmao downgrade where

Edited January 25, 2010 by badboy657

[aspire27]

yes thats terrible isn;t it?

ECM keeps it cold from Thr to Mon with some places seeing snow,imposible to know at this range where but i cant nderstand people using the smiley when we are looking at a 4 to 5 day potent cold spell.

maybe CV would prefer SW winds or somethinhg?

Is it potent? any predicted 2m temps?

[TEITS]

Unfortunately ECM12z is a downgrade in terms of cold uppers etc up to T144......Shame but

true............Minus 8 uppers the max we can expect to see in the reliable timeframe.

Always likely with a N,ly. Very rare to see much colder upper temps i.e -12C etc with the exception of N Scotland. Simple reason is due to the longer fetch across the sea compared to an E,ly.

Having said this upper temps of -8C will mean surface temps ranging from 0 to 3C and possibly around 5C in the SW. Obviously the mountains of Scotland will see sub zero temps.

Back to the ECM and to be honest its rather poor in F.I and I knew as much at +168. If we are to see this cold spell prolonged i.e E,ly then we need LP to sink SE at the +168/+192. timeframe.

[Lewis]

i do not agree 2000 or 2001 snow band with thunder snow moved south even here in the southcoast we had an inch.

i cant see why any where in the uk get snow showers.

ukmo ecm great where it goes beyond is anyones guess its also something that held firm last december january with high in the alantic and over us was very cold under that block ive got a feeling beyond the northerly the block could sit west of us or even apon us.

as for snow it could fall anywhere how much is anyones guess aswell.

but for now anyway winter is back.

The only way you will see showers pushing inland affecting central and S areas will only be with an associated trough/front.

[Cecil Hogmanay Melchett]

Is it potent? any predicted 2m temps?

850's are low enough to support snow widely i would imagine.BBC N24 talking of artic air sweeping south on Fri.

I guess some folk are never happy.

[cooling climate]

Bags of potential from the t240 chart.

I feel the easterly is gaining some momentum, further improvements likely.

Unfortunately ECM12z is a downgrade in terms of cold uppers etc up to T144......Shame but

true............Minus 8 uppers the max we can expect to see in the reliable timeframe.

GFS has only got 850 temperatures of -7c over east Midlands, east Anglia and the southeast

for Saturday afternoon yet a projected 2m temperature of -2c.

I am sure this was all discussed during the last cold spell.

[Thundery wintry showers]

FI does throw up a different scenario to most other runs so far, going for high pressure coming close to Britain almost immediately. Significantly we get the duration of the northerly increased by a further day on this run, much like with the UKMO, perhaps indicating that although it will break down after a few days, the GFS might be being a little too progressive.

The Euros make a lot less of Friday's disturbance meaning snow instead of rain for many western areas but staying dry and clear in the central belt of the country. With a slight easterly component to the wind the ECMWF for Friday would mean snow showers heading a fair distance inland in the east.

[Polar Continental]

It seems, some people on here will never be happy unless the models are showing the next ice age, a few comments made further up are straight out of a comic book lol.

The models are showing a northerly for the UK, not Iceland, -5c to –8c uppers are the norm in most maritime arctic air from northern England south, anything lower would be a bonus.

Take a look in the archives, you will see that the majority of northerly outbreaks south of the Scottish borders will show this.

Even during the bitter winter of 1962-63, uppers below –10c were not as common as you would think, -5c to –8c was the norm even in that winter.

If the 12z modes verify, then a good chance of some wintriness over northern England and even southern areas if the instability in the northerly hold true to the models.

[MR EXTREMES]

The only way you will see showers pushing inland affecting central and S areas will only be with an associated trough/front.

i agree but its not worth saying it wont happen when its to far out to be forecasting where snow will fall in my years on this planet ive seen showers push to the far southcoast from the north trough snow and showers.

but this is for another forum the outputs are fantastic its not been to warm here in the south today and the weekend will be cold -8 air is pukka.

as for longterm fi its not worth the typing effort although it does look like it gets messy but then models differ in fi so until each show a full blown sw flow in the right timeframe im happy atm.

[Cecil Hogmanay Melchett]

It seems, some people on here will never be happy unless the models are showing the next ice age, a few comments made further up are straight out of a comic book lol.

The models are showing a northerly for the UK, not Iceland, -5c to –8c uppers are the norm in most maritime arctic air from northern England south, anything lower would be a bonus.

Take a look in the archives, you will see that the majority of northerly outbreaks south of the Scottish borders will show this.

Even during the bitter winter of 1962-63, uppers below –10c were not as common as you would think, -5c to –8c was the norm even in that winter.

If the 12z modes verify, then a good chance of some wintriness over northern England and even southern areas if the instability in the northerly hold true to the models.

excellent post sir.

[Uncle_Barty]

i do not agree 2000 or 2001 snow band with thunder snow moved south even here in the southcoast we had an inch.

i cant see why any where in the uk get snow showers.

That thundersnow (28 Jan 04) came as a result of a very active cold front/line squall that came straight down from the north introducing arctic air for a day or two.

A northerly airflow almost never delivers snow down here on the coast as the air is too dry by the time it gets here.

I am expecting a few crisp cold dry days out of this before it turns less cold next week.

[Ben_Cambs]

A mixed bag of GEFS ensembles tonight, some going for a return of cold in deep deep FI and others going for something milder. All in all, a very uncertain outlook IMO, I would put FI at T+168 atm

[phil nw.]

ECM goes much warmer after the Northerly,on this run.

This chart is a nightmare for cold lovers.

I can`t remember a chart with +10c 850`s since Winter started.

[MR EXTREMES]

A mixed bag of GEFS ensembles tonight, some going for a return of cold in deep deep FI and others going for something milder. All in all, a very uncertain outlook IMO, I would put FI at T+168 atm

one thing i have noticed with the gefs ensembles is none are very mild which has been as classic feature so far this winter and long may it continue lol.

anyway there showing = chances of milder or colder its very exciting.

but as it stand the models up to the almost realiable timeframe has some colder air im happy with tonights infact todays outputs.

as for thundesnow thanks for pointing out the year 2004.

lol but i still do not agree with snow not falling from showers from the north its right that normally there out of juice by the time they get here but its not a rule.

and excellent post by polar c

[Lewis]

one thing i have noticed with the gefs ensembles is none are very mild which has been as classic feature so far this winter and long may it continue lol.

anyway there showing = chances of milder or colder its very exciting.

but as it stand the models up to the almost realiable timeframe has some colder air im happy with tonights infact todays outputs.

as for thundesnow thanks for pointing out the year 2004.

lol but i still do not agree with snow not falling from showers from the north its right that normally there out of juice by the time they get here but its not a rule.

and excellent post by polar c

Im sorry to dissapoint you, but other than a frontal event, or a trough disturbance in the flow, expect to be cold and dry during the day, with a harsh frost over night.

[ChartViewer]

Lol, I'm sure Chartviewer is taking the mick here. In most recent winters the coming Northerly would be THE highlight of the winter.

Ian,

The ecm12z IS a downgrade from the previous two 12z's.....Because the Northerly shows rain for most

with Western, Cenral and South Central not seeing much out of a snow event.......No reload

to my eyes........No need to start going 0n about the early Jan synoptics as they have gone

and have NO bearing on what we are seeing now....Which is a Mid atlantic High toppler end of

Sorry but the synoptics arent that great

Regards

CV

[Frosty.]

A strong Arctic blast is now guaranteed and it will begin to affect northern scotland as early as wednesday afternoon with showers turning wintry as NNW winds increase to near gale force. It looks a straight Northerly on the gfs,ukmo and ecm 12z so the wishbone effect will apply, meaning that snow showers will be mainly confined to western, northern and eastern coastal areas with northern scotland and the n.isles likely to be hardest hit by the snow and N'ly gales between wed night and sun afternoon with drifting in the strong winds. Most inland parts of the uk will probably have almost unbroken sunshine but also very cold and with widespread sharp frosts. FI not looking wintry with a trend towards less cold / milder conditions and the ECM 12z beyond the weekend is hardly eye catching but since it's 7-10 days away it has plenty of time to improve.

[grab my graupel]

Evening folks, may I remind you that there is a 'Model moods' thread available