Cold Spell Discussion

[Osbourne One-Nil]

Inland temperatures of +1c does not constitute a thaw in my book. As for coastal areas they were expected to rise

2or 3 degrees above freezing for the next 24 to 36 hours.

Certainly we have lost the deep cold but a thaw, I don't think so.

Well, I'm 600ft up in the far north, 40 miles from the sea, and it's 2.6C. The snow is melting - slowly. Perhaps it's temporary, but 2.6C and melting snow is a thaw in my mind.

[snowmackem]

Well, I'm 600ft up in the far north, 40 miles from the sea, and it's 2.6C. The snow is melting - slowly. Perhaps it's temporary, but 2.6C and melting snow is a thaw in my mind.

Oon, agreed. Snow falling off roofs, clear patches appearing on the ground, everything dripping everywhere, snow gone from cars and feeling comparatively mild (out of the wind), let alone 2" shaved off the top of level measurable snow = THAW, no two ways about it.

Lol, we now have Thaw Denyers !

Karl

[snowingtequila]

Not quite a thaw here but the snow has lost its powderyness which is the first sign of a change.

[ukmoose]

I think we have to say that this slight thaw has taken nearly everyone by surprise. Yesterday here, during daylight hours, the temperature did not get above minus 1. Light snow was forecast for up to 24 hours, maybe longer and the temperature was set to remain below zero.

I could tell when we went out at 7.30 yesterday evening that something was 'wrong' already - the temperature had risen just enough to get above freezing and whilst no precipitation, the air felt (and still feels) 'damp' not dry and cold.

I can only assume that the warm front had marginally higher temperatures than expected and that, along with passage over the North Sea, made all the difference.

Can't quite explain the snow in the south west though..?

And are we now in for a slow thaw over the next few days as warmer air tries to push in?

Whatever happens it has been a good spell of cold whether if not exceptional in these parts. Certainly more exceptional in other parts of the country though and the north may yet still remain cold.

[Mark Bayley]

I think most can expect a slow thaw over the coming days. Its melting steadily over here. But not at an extreme rate. Would probably take a a good few days to melt! Which is the same for everyone else with good accumulations. Lets not forget it will freeze overnight if temps drop! I can't say I'm to disappointed. five days of around 10cm-15cm on the ground is not to bad. It was never going to stick around for ever. Even if the snow does melt its not going to turn mild. Just less cold for most away from the South West and some Southern Counties. My next hope is for a warm spring with a mixed Feb!

[Terminal Moraine]

No thaw here as yet although the temp is close to 0c, snow is still drifting above 300m.

[High Altitude]

I'll no doubt be as popular as a skunk in a very small bag but it has to be said. I've just posted this in the Yorks etc thread as there seems a lack of realism in there also-no doubt in the other regional threads.

I find some of the comments on this regional thread and the model thread pretty amusing.

What we have this morning was correctly predicted about 5 days ago. The deep cold going and being replaced by +ve daytime temperatures, slight precip and that of sleet or at best wet snow, frost unlikely after late Saturday evening.

What have we got-precisely that-so why the consternation?

I've plotted outputs from Extra and NMM daily and its not done at all badly-it has failed to get the minimum values I've had but other than that its done okay.

I suggest a closer and more objective look at the models for some people and an acceptance that the various models will show slightly different end solutions. The trick is being objective and plotting a 'middle' path. That way there is less chance of thinking something is going to happen when the reality is its not going to.

As to what is likely through the latter end of the week then its not going to get mild anywhere other than the far SW. Will the cold return, whatever that means. If you mean the bitter cold with -12C 850's, then that currently looks unlikely as there is no source of such cold air. That is not to say it cannot develop as a result of the weather most of Europe and Scandinavia has experienced for the past 7-14 days-it can. In the meantime we have to live with a more traditional British winter scene-heavy snow in places, especially over high ground with a more wintry mix for southern lower lying areas and the lovely fluffy snow many of us had for several days becoming rather slushy by day and horribly icy when we get an overnight frost.

I'll go now before I get lynched!

A good informative post as always but not quite sure i agree with your assessment.

Since last Sundays countryfile all talk was off scattered snow showers throughout the week, heavy in places with a significant snow event for this weekend - Sat/Sun/Mon brought about by Easterly winds.

This weekend event was forecast to effect all regions from the midlands south starting in the East and spreading West with substantial accumulations in parts. Throughout the week all forecasts have continued with this theme although weakening the precipitation as we’ve got closer to the event.

Even last night both BBC and SKY were forecasting a front approaching from the East bringing persistent light/medium snow to effect all southern regions which would produce significant accumulations throughout Sunday into Monday. This morning, 8 hours later and we’ve got a totally different picture. Now, the forecast is for light patchy snow flurries that seem to be petering out to nothing in most parts with positive temp values and a slight thaw. I’m sure some have received significant snow and are still in negative temp territory but the ‘event’ was always forecast to effect a vast area of England and Wales, not just sporadic pockets.

From a generalised point of view the Mid week snow seems to have been the more significant producing snow with this weekends pretty much a non event.

[Thundery wintry showers]

I think we have to say that this slight thaw has taken nearly everyone by surprise. Yesterday here, during daylight hours, the temperature did not get above minus 1. Light snow was forecast for up to 24 hours, maybe longer and the temperature was set to remain below zero.

I could tell when we went out at 7.30 yesterday evening that something was 'wrong' already - the temperature had risen just enough to get above freezing and whilst no precipitation, the air felt (and still feels) 'damp' not dry and cold.

Yes- as early as 6pm last night I noticed that the 12cm of powder snow at UEA Norwich had compacted quite a bit, which if there isn't any sunshine about, strongly implies temperatures significantly above freezing. I haven't checked the depth yet today but it's likely to be less than half that.

I did warn people that there would be some warmer air tied in with this system and that it would be marginal, with a slow thaw near the east coast of Scotland and N England, but the extent of it has taken even me by surprise. I certainly didn't expect upland parts of Cumbria to be getting 2.6C and a thaw- I thought those conditions would be reserved for the likes of South Shields (where it's currently a whopping 5.1C!).

The GFS may have been very poor at modelling this cold spell but its 2m temperature projections from 3-4 days out were very good, and were my basis for suspecting something like this might happen but on a much smaller scale than observed.

Once this lot shifts it will turn colder again for most, with chances of further snow events, but unfortunately for many it will be a case of partially thawed/refreezed ice on the ground which will be of little use to either snow lovers, or those hoping for a complete thaw and a pattern change to much milder weather. However, it's worth noting that this was traditionally a problem in many of the old-school winters of the 40s, 50s, 60s and 1978-87- snow in the UK has always been marginal.

[robnor1]

I'll no doubt be as popular as a skunk in a very small bag but it has to be said. I've just posted this in the Yorks etc thread as there seems a lack of realism in there also-no doubt in the other regional threads.

I find some of the comments on this regional thread and the model thread pretty amusing.

What we have this morning was correctly predicted about 5 days ago. The deep cold going and being replaced by +ve daytime temperatures, slight precip and that of sleet or at best wet snow, frost unlikely after late Saturday evening.

What have we got-precisely that-so why the consternation?

I've plotted outputs from Extra and NMM daily and its not done at all badly-it has failed to get the minimum values I've had but other than that its done okay.

I suggest a closer and more objective look at the models for some people and an acceptance that the various models will show slightly different end solutions. The trick is being objective and plotting a 'middle' path. That way there is less chance of thinking something is going to happen when the reality is its not going to.

As to what is likely through the latter end of the week then its not going to get mild anywhere other than the far SW. Will the cold return, whatever that means. If you mean the bitter cold with -12C 850's, then that currently looks unlikely as there is no source of such cold air. That is not to say it cannot develop as a result of the weather most of Europe and Scandinavia has experienced for the past 7-14 days-it can. In the meantime we have to live with a more traditional British winter scene-heavy snow in places, especially over high ground with a more wintry mix for southern lower lying areas and the lovely fluffy snow many of us had for several days becoming rather slushy by day and horribly icy when we get an overnight frost.

I'll go now before I get lynched!

With regard to the first line above - yes you had it right..........according to the BBC late last night and Francis Wilson on the back of the Times (and Sky) today they had colder & snowier solutions than yours which are both wrong especially to central south area & western M4 corridor.

Sounds like you should be on the box.....

[Snowyowl9]

Still -0.5c here with odd light snow grains and some drifting,quite abit of drifting overnight.

[cooling climate]

I must admit to being at a loss to understand the poor precipitation forcasts so far this weekend.

The forcasts and warnings were still calling for moderate to perhaps significant snowfall for east Anglia,

the 3 counties, London and the south east during the 24 period from midday yesterday through the night

and into today.

Looking at the radar yesterday afternoon I could not see where this snow was coming from and when

family members rang to ask when was the bad weather to set in I replied "I haven't a clue" as there was

no evidence of any adverse weather on the radar for these areas in the near or longer term(overnight).

The radar images showed no precipitation over northeast France or the low countries during this time

period either and with the higher resolution radar imagery that they have at there disposal this must

have been obvious to them as well.

John I wonder if you could shed some light on this as I was just wondering in situations like this do they

tend to generalize more rather than be specific.

[Nick L]

the breakdown has already happened here in the south fast thaw going on drizzle.

id say m4 north staying in the colder air for awhile yet,

anything south of this by thursday will have to wait for a reload.

but im dissapointed its gone but happy with the memory of winter 2010 it was brillant.

*Checks calendar* Sorry I must be going mad, I could have sworn there was another half to winter somewhere...

[StormChaseUK]

Looks like the cold spell has ended , latest beeb forecast shows positive temps now for much of south

[mushymanrob]

yes the term-lost the deep cold seems about right to me.

Its pretty obvious I would have thought that if temperatures are above freezing then some kind of 'thaw' Will lake place. Unless the temperatures get above about 4C then its a slow one certainly not rapid.

The weather seems to show no signs of becoming mild by definition in any time scale.

Regarding the precipitation-I continue to suggest that slight intensity-outside the exceptional cold values at 850mb for most of last week, almost always lead to a 'wintry' mix-rain, sleet, frozen raindrops, rain. For snow to fall in the conditions we are now in then height is required and/or intensity. Both will give snow, maybe wet rather than the dry variety of the past week but snow but not with very slight intensity at any low level, near the sea or not.

its thawing here right now, slowly but surely. looks like this is our lot for the week, cold, dull, breezy.

[Guest]

Once this lot shifts it will turn colder again for most, with chances of further snow events, but unfortunately for many it will be a case of partially thawed/refreezed ice on the ground which will be of little use to either snow lovers, or those hoping for a complete thaw and a pattern change to much milder weather.

For many of us in Scotland this cycle of snow/thaw/freeze has already been in full swing on and off since the start of the cold spell. I posted up countless photos in the Scottish thread of thick layers of white ice created from frozen slushy snow which had formed during these types of milder periods. Undisturbed "white" cover in my local area is between 6-8inches deep; only the top 2-3 inches of this is proper snow, the rest is varying types of crusty snow and ice from a few days of +2C or +3C around New Year time. This does of course mean that we have a 4 inch layer of fairly solid ice on the ground which will not melt in air temps of 3C or 4C

[Nick L]

The Met Office early warnings for today have been CANCELLED, never seen that before. They are admitting they got it wrong for a change!

[Upgrade]

I must admit to being at a loss to understand the poor precipitation forcasts so far this weekend.

The forcasts and warnings were still calling for moderate to perhaps significant snowfall for east Anglia,

the 3 counties, London and the south east during the 24 period from midday yesterday through the night

and into today.

Looking at the radar yesterday afternoon I could not see where this snow was coming from and when

family members rang to ask when was the bad weather to set in I replied "I haven't a clue" as there was

no evidence of any adverse weather on the radar for these areas in the near or longer term(overnight).

The radar images showed no precipitation over northeast France or the low countries during this time

period either and with the higher resolution radar imagery that they have at there disposal this must

have been obvious to them as well.

John I wonder if you could shed some light on this as I was just wondering in situations like this do they

tend to generalize more rather than be specific.

I was led to believe there'd be 8 inches of snow by the end of today- bbc London were going with this as late as 8pm yesterday evening. It has turned out to be nothing of the sort, just light rain and a thaw. there wasnt even a hint it would rain on the forecast, indeed snow forecast was greater, later in the day, with threats of drifting in streghtening winds etc. no winds came and it rained.

Steve Murr was right - he saw the way it was going early yesterday . hats off to him.

Edited January 10, 2010 by jimmyay

[johnholmes]

This does of course mean that we have a 4 inch layer of fairly solid ice on the ground which will not melt in air temps of 3C or 4C

that is pretty true CmD

[damianslaw]

Certainly has turned out much milder this morning than anticipated, with temps of 2 degrees at 10.00am and a slight thaw taking hold turning everything at lower levels very slushy and mucky indeed. However maxes of 2-3 degrees followed by nights close to freezing which looks the order of the day for the upcoming week is hardly mild, so the thaw will be a slow drawn our process, ground above about 300m will probably see no real thaw at all, so the fells will keep their white cloak.

Its been a notable cold spell here, with a 7 day period of not getting above freezing from the 3rd-9th Jan. Last time that happened was between 23rd dec - 31st dec 1995.

[TEITS]

The temps certainly have been surprising. However im going to show you a PM I recieved yesterday morning.

"Hi TEITS, we have not spoken before but i have a question i would like to ask which is, i have noticed that you use the NMM Hi Res model and i am concerned about the temperatures it is showing for Sunday when we are hoping to get some persistent snow.It is showing 3/4 degress quite widely across our region and a snow risk of only 45% and as you have a greater knowledge of model watching than me would you share my concerns?

Hope you don't mind me asking you personally but i value your input on model threads and thought you are the man to ask."

My reply was not to worry as all the other models disagreed with the NMM including the BBC/Met O forecasts. I have certainly learn't a lesson over these past few days and shall spend more time focussing on the NMM rather than the BBC!

[MR EXTREMES]

*Checks calendar* Sorry I must be going mad, I could have sworn there was another half to winter somewhere...

sorry yeah im not saying winter 2010 is over honestly ive got some good memories from this event.

i think met should have revised there warnings lastnight,

i think this was very poor information given here,

regardless of whether i was waiting for a snow event or not,

but theres been panic buying here in the south for milk and stuff and this was evident yesterday,

what im saying is more money is waisted while police and special units setup for cold weather when instead its melting,

this also changes everything for the reast of the week in regards to very snowy event in the south,

the models are unsure aswell but i think the shift this time will be a little quicker than most would expect,

but it does not mean the cold is gone for the rest of winter and reload is very much possible.

i no this is of topic but id love us all to go into the chatroom we can then let rip lol:whistling:

[Nick L]

Seeing as the end of the REAL wintry spell is now pretty much here, time for a quick sum up:

Snowfall - Nothing special

Temperatures - Very cold

Longevity - Very good

All in all, not bad compared to the dross we have been used to.

[Upgrade]

The Met Office early warnings for today have been CANCELLED, never seen that before. They are admitting they got it wrong for a change!

A bit of a boo boo for the met. The thaw is underway across the UK now. Just as we were looking forward to another big dump.

People underestimated the warm front pushing from the east , it had too much of a southerly element to the origin of the air, perhaps? Where did our forecast of strong easterlys go? its calm here ?

anyway i'm quite happy, had a great day in Richmond Park yesterday , and walked on frozen ponds- had nearly a week of snow in London which is rare ( plus the week before Christmas). Not bad when we havent even finished the second week in Jan.

[azores92]

sorry yeah im not saying winter 2010 is over honestly ive got some good memories from this event.

i think met should have revised there warnings lastnight,

i think this was very poor information given here,

regardless of whether i was waiting for a snow event or not,

but theres been panic buying here in the south for milk and stuff and this was evident yesterday,

what im saying is more money is waisted while police and special units setup for cold weather when instead its melting,

this also changes everything for the reast of the week in regards to very snowy event in the south,

the models are unsure aswell but i think the shift this time will be a little quicker than most would expect,

but it does not mean the cold is gone for the rest of winter and reload is very much possible.

i no this is of topic but id love us all to go into the chatroom we can then let rip lol:whistling:

sorry, i know this isnt strictly on topic mods, so delete if you want. what i will say is this, although the event for the south east wasnt correct, the bbc did highlight the fact that snow today would be light and patchy, with maybe a couple of cms piling up. there wasnt a hint of significant snowfall from rob mcelwee last night(save the southeast which was wrong, and the met office have admitted fault). lo and behold, today is cloudy with light and patchy snow. for most of britain, the forecast hasn't been too bad imo. i think its time to return to a more average outlook imho. the icy surfaces are making things treacherous, everybody is fearing the thaw and looking for that breakdown with anxiety. at least with an average outlook, you cant be getting yourself excited only to be let down, and most importantly, you arent clinging to the models 24/7! its been a brilliant memorable spell of weather, but this is the british isles, not poland, and normality is likely to ensure sooner or later.

Edited January 10, 2010 by azores92

[Thundery wintry showers]

This cold spell has, on its own, produced about as much snow over the UK as a whole as the entire 2008/09 season, so a pretty remarkable spell of weather. And although the severest is over (here I agree with Mushymanrob- a cold, dull, breezy week is in prospect for most) the cold spell is not yet over. Temperatures will still be a few degrees below the January average in most parts and while there is the continued chance of attacks from the Atlantic, there's also the continued chance of attacks from the east.

I think it's unfair to slag off the Met Office too much regarding the forecasts for today, because let's face it, all of us got it wrong to some degree. The NMM model has proved itself, once again, to be a good forecast tool as it called the current event pretty well at 24 hours out.