Winter / Autumn 2009-10 Part 4

[Don]

A fairly typical Nino Winter expected by IB then with generally mild conditions dominating until February. Sounds quite feasible. However, I'm sure we will have at least some short lived cold snaps between now and February!

[karyo]

Even if it is a mild winter, frosty nights will be quite common, am i correct?

It depends! The diabolicaly mild winters of 1997/8 and 2006/7 had precious little frosts! This lead to trees blossoming early etc.

However, non extreme mild winters have relative frequent frosts.

Karyo

[Backtrack]

I don't think Ian's forecast specifies no snow at all during December and January, it just suggests a dominance of warm south-westerlies and high pressure to the SE. But most such months do have occasional snow events particularly in the north- take 1989/90 for example. 1988/89 was exceptional for its absence of snow events in December and January- even December & January 1974/75 had a few snow events in the north.

And indeed, it is just a forecast, and no long-range forecast should ever be taken as gospel.

Thanks Ian.

Hopefully we will get a few cold events.

It depends! The diabolicaly mild winters of 1997/8 and 2006/7 had precious little frosts! This lead to trees blossoming early etc.

However, non extreme mild winters have relative frequent frosts.

Karyo

Cheers Kayro

Edited November 13, 2009 by Backtrack

[Rich_Clements]

I think we'll get some colder interludes but overall I have a horrible feeling the winter will be on the mild side, not by any scientific data just a hunch.

[SP1986]

I can't see anywhere that anyone said there wouldn't be any cold spells until February.. however the pasychology is interesting, I can see many people getting irritated, due to most likely chances being of a milder than average winter. Of course even people with very limited meteorological knowledge know that a mild winter doesn't mean there will be no snow, it's fairly obvious there will be at least one snow event in the UK this winter.

[Fozfoster]

I can't see anywhere that anyone said there wouldn't be any cold spells until February.. however the pasychology is interesting, I can see many people getting irritated, due to most likely chances being of a milder than average winter. Of course even people with very limited meteorological knowledge know that a mild winter doesn't mean there will be no snow, it's fairly obvious there will be at least one snow event in the UK this winter.

i hope the one snow event is on the 25th december, Just had a fiver @ 7/1.

[Rich_Clements]

Of course even people with very limited meteorological knowledge know that a mild winter doesn't mean there will be no snow, it's fairly obvious there will be at least one snow event in the UK this winter.

I think I come into that catagory

[Backtrack]

I can't see anywhere that anyone said there wouldn't be any cold spells until February.. however the pasychology is interesting, I can see many people getting irritated, due to most likely chances being of a milder than average winter. Of course even people with very limited meteorological knowledge know that a mild winter doesn't mean there will be no snow, it's fairly obvious there will be at least one snow event in the UK this winter.

Because of El Nino though, doesn't that mean they will be very short lived?

I also want an event on 24th/25th December.

[SP1986]

Maybe by the coast, in my experience though it doesn't make much difference inland.

[Backtrack]

Maybe by the coast, in my experience though it doesn't make much difference inland.

My location is quite near the coast

Seriously im going to smash my weather stations up now.

[osmposm]

Gee I wonder what they said in the MWP or LIA!

Well, in the LIA they probably said "Damn, it's cold - is it ever going to change?" . Of course it did, but it took a very long time - and it still used to throw us odd, nasty reminders of how it had been.

As to the MWP, well we still don't really know how it affected the UK in detail - and there is good evidence of the Thames freezing over, for example, from time to time during the period, so maybe it wasn't so mild....but even if it was comparable with today, what I bang on about is how the current phase (assuming that's all it is) is unprecedented within our cultural memory. That - at the very least - saddens me greatly.

[MR EXTREMES]

Wow... Seriously that sucks. Forget it, i hate winter now. How can we have nothing not even frost, colder night NOTHING until Feb! that makes no sense! :lol:

ofcoarse we will have cold snaps and snow and frost but prolonged not likely let be honest prolonged cold is rare anyway.

[Alex95]

It depends! The diabolicaly mild winters of 1997/8 and 2006/7 had precious little frosts! This lead to trees blossoming early etc.

However, non extreme mild winters have relative frequent frosts.

Karyo

However, even 1997/98 had a couple of significant snowfalls here. 06/07 and 07/08 had none, and you have to go back quite a long time to find a winter as poor a those ones, and a very long time indeed to find 2 consecutive winters that poor.

It is worth noting that if January 2008 was 1°C colder than it was, there'd have probably been 3 significant snowfalls that month.

[Solar Cycles]

Well, in the LIA they probably said "Damn, it's cold - is it ever going to change?" . Of course it did, but it took a very long time - and it still used to throw us odd, nasty reminders of how it had been.

As to the MWP, well we still don't really know how it affected the UK in detail - and there is good evidence of the Thames freezing over, for example, from time to time during the period, so maybe it wasn't so mild....but even if it was comparable with today, what I bang on about is how the current phase (assuming that's all it is) is unprecedented within our cultural memory. That - at the very least - saddens me greatly.

Off topic, but I couldn't let this pass. Where is this evidence, that the Thames froze over during the MWP?

Yes I agree, the last 22 years have been mostly disappointing. But cycles come, and cycles go, so chin up, things are a changing!

[karyo]

It is worth noting that if January 2008 was 1°C colder than it was, there'd have probably been 3 significant snowfalls that month.

Yes, January 2008 was very wet and the jet was quite southerly in the first part of the month but not southerly enough unfortunately. The second half was milder and still wet. A very disappointing month.

There are many recent examples where we were at the wrong side of marginal for snow. That's why I don't like the persistent mildness we are having. It leads to higher SSTs so the cold spells that arrive in the latter part of winter are moderated and coastal areas in particular struggle to see snow.

That's one big advantage last winter, the autumn that preceded it had cool temperatures

that helped to lower the SSTs.

Karyo

Edited November 13, 2009 by karyo

[Cheese Rice]

Well i dont really mind if we get another mild winter, its not like we aren't used to it, it would hardly be a shock to the system. Most places see some snow every year no matter how mild the winter is. And we will still see frosts, there will be frost and snow in December, just not everywhere. Most places in the South didn't see any snow till Februarylast year. Most of you didn't mind as that one week was worth it, so who's to say it won't happen again.

[reef]

There are many recent examples where we were at the wrong side of marginal for snow. That's why I don't like the persistent mildness we are having. It leads to higher SSTs so the cold spells that arrive in the latter part of winter are moderated and coastal areas in particular struggle to see snow.

That's one big advantage last winter, the autumn that preceded it had cool temperatures

that helped to lower the SSTs.

Karyo

It doesnt really make much difference to be honest. Despite a colder Autumn, almost all of the events last year were the wrong side of marginal here (December and January had no lying snow). Whats more important is the source and potency of the cold air. The problem last winter was that the upper air was generally never from very cold sources. Indeed, the winter as a whole comprimised mainly of weak northerlies sourced from not very far north. The only real cold air of note was from that early Feb easterly, but that was so brief it didnt really gives us anything here.

Thats not to say mild synoptics dont have an impact. A classic example was January/February 2005. The mild, zonal January meant tropical maritime air was sent deep into Russia and to our north-east. This meant that the northerly on 13th February and the easterly in the final third of the month produced little in the way of lying snow unless you were inland with a bit of altitude. The northerly on the 20th however was sourced when cold air was present, so many eastern areas had snowcover then.

[osmposm]

Off topic, but I couldn't let this pass. Where is this evidence, that the Thames froze over during the MWP?

See this post of mine (and follow the link within for more detail): http://forum.netweather.tv/topic/57341-winter-autumn-2009-10/page__st__170__p__1607727entry1607727

But if we want to debate it more, SC, probably best over in Climate Change - a new thread even....?

By the way, I don't know if you saw this post of mine taking up your winter wager! It got a bit stuck at the end of the closed thread: http://forum.netweather.tv/topic/57341-winter-autumn-2009-10/page__st__459__p__1611708entry1611708

Ossie

Edited November 13, 2009 by osmposm

[weather eater]

Off topic, but I couldn't let this pass. Where is this evidence, that the Thames froze over during the MWP?

Yes I agree, the last 22 years have been mostly disappointing. But cycles come, and cycles go, so chin up, things are a changing!

827

917 possibly

923 possibly

998

855/56 possibly

908 possibly

1020 possibly

1047 possibly

1061

1092/93 possibly

1114/15 possibly

1149/50

1204/05

1209/10 possibly

1224/25 or 1225/26 possibly

1269/70

1281/82

1309/10

http://booty.org.uk/booty.weather/climate/histclimat.htm

Plenty of other severe winters that might have caused the Thames to freeze. We need to keep in mind that in those days it was easier for the Thames to freeze, this was the case until the Thames was made deeper and less wide due to work on the banks during the Victorian era.

[Thundery wintry showers]

I think SSTs can have a big impact in coastal areas if both the autumn and winter are mostly very warm. July 2006 was a record-breaking hot month, Autumn 2006 was a record-breaking warm one and the winter of 2006/07 was then one of the top ten warmest winters on record. The result was that the SSTs around Britain were exceptionally high. Thus, when we got synoptically potent-looking northerlies around 22-25 January, 5-9 February and 18-20 March accompanied by fairly deep cold air, the SST modification was so huge that many of the usually-favoured northern and eastern coasts struggled to see any accumulations of snow at all. At Cleadon, a NE'ly from the Arctic on 22nd January, with 850hPa temperatures of around -8C, gave a maximum of 7.5C, and even Newton Aycliffe in Durham managed 6.3C.

But then again, two of the most dramatic November northerlies of the last two decades for north and east-facing coasts- 17th November 1995 and 8th/9th November 2001- occurred when SSTs in the North Sea were unusually high following exceptionally warm Octobers. Despite this, there was a good peppering of sleet and snow showers, and the sharp contrast between the deep cold air and the anomalously warm sea also produced a fair amount of thundery activity.

But no matter how anomalously high those SSTs are, a prolonged spell of below average temperatures in winter will tend to bring them down close to normal quite quickly, as happened in the Decembers of 1995 and 2001.

[LomondSnowstorm]

CFS weekly average was showing colder than average for most of the winter for months but has just changed to average or milder than average - slightly worrying for cold lovers but hopefully not too significant.

[Solar Cycles]

See this post of mine (and follow the link within for more detail): http://forum.netweat...7entry1607727

But if we want to debate it more, SC, probably best over in Climate Change - a new thread even....?

By the way, I don't know if you saw this post of mine taking up your winter wager! It got a bit stuck at the end of the closed thread: http://forum.netweat...8entry1611708

Ossie

At best they are assuming going that far back. However a very interesting read Os!

As for the bet, your right on that one!

[reef]

I think SSTs can have a big impact in coastal areas if both the autumn and winter are mostly very warm. July 2006 was a record-breaking hot month, Autumn 2006 was a record-breaking warm one and the winter of 2006/07 was then one of the top ten warmest winters on record. The result was that the SSTs around Britain were exceptionally high. Thus, when we got synoptically potent-looking northerlies around 22-25 January, 5-9 February and 18-20 March accompanied by fairly deep cold air, the SST modification was so huge that many of the usually-favoured northern and eastern coasts struggled to see any accumulations of snow at all. At Cleadon, a NE'ly from the Arctic on 22nd January, with 850hPa temperatures of around -8C, gave a maximum of 7.5C, and even Newton Aycliffe in Durham managed 6.3C.

But then again, two of the most dramatic November northerlies of the last two decades for north and east-facing coasts- 17th November 1995 and 8th/9th November 2001- occurred when SSTs in the North Sea were unusually high following exceptionally warm Octobers. Despite this, there was a good peppering of sleet and snow showers, and the sharp contrast between the deep cold air and the anomalously warm sea also produced a fair amount of thundery activity.

But no matter how anomalously high those SSTs are, a prolonged spell of below average temperatures in winter will tend to bring them down close to normal quite quickly, as happened in the Decembers of 1995 and 2001.

Indeed, my observations in 2006/07 were pretty similar to yours. Aside from a dusting in January, snow failed to accumulate at all here during that season. The well above average SSTs also helped to hold temperatures up close to the coast at night, so much so that even in calm, clear conditions under relatively cool upper air we failed to record a frost.

With northerly blasts, the potency of the polar air and the exact wind direction make a major difference. A straight northerly or NNE flow tend to be the most productive for snowfall as long as 850hPa temperatures are -7C or -8C. However, with a north-easterly flow 850hPa air of -8C may often not be enough. The dates you mention in January and March 2007 are classic examples, but even more so at the end of February 2005 when it rained here despite 850hPa air temperatures of -9C and -10C (the same day Kent got buckets of snow) - and that was when SSTs were at their lowest.

[Snowyowl9]

However, even 1997/98 had a couple of significant snowfalls here. 06/07 and 07/08 had none, and you have to go back quite a long time to find a winter as poor a those ones, and a very long time indeed to find 2 consecutive winters that poor.

It is worth noting that if January 2008 was 1°C colder than it was, there'd have probably been 3 significant snowfalls that month.

2007/08 wasn`t a total loss if you liked freezing fog and a few ice days in december,and a brief easterly in January,and a little cold zonailty in the same month.

2006/07 did give a very large snowfall on february 9th and almost got down to -6c on the 7th.

But I suppose those 2 years did remind me of the late 80`s,but with no easterlies or freezing fog etc.

Spring 2008 was very much difference of course,with snow late March/April.

It`s only really that 1988/89 winter when it was november snow/N-ly and April 89 very cold easterly was the memorable part of that year in terms of cold/snow.

Otherwise these days it`s the april cold and snow that seems to of dissapeared most notable in the 00`s

[J10]

Indeed, my observations in 2006/07 were pretty similar to yours. Aside from a dusting in January, snow failed to accumulate at all here during that season. The well above average SSTs also helped to hold temperatures up close to the coast at night, so much so that even in calm, clear conditions under relatively cool upper air we failed to record a frost.

With northerly blasts, the potency of the polar air and the exact wind direction make a major difference. A straight northerly or NNE flow tend to be the most productive for snowfall as long as 850hPa temperatures are -7C or -8C. However, with a north-easterly flow 850hPa air of -8C may often not be enough. The dates you mention in January and March 2007 are classic examples, but even more so at the end of February 2005 when it rained here despite 850hPa air temperatures of -9C and -10C (the same day Kent got buckets of snow) - and that was when SSTs were at their lowest.

In February 2007 (9th), there was a very significant snow event that gave about 4-5 inches that fell during daylight hours right down to sea level. These couple of days were the only notable snow events, with the rest of a winter being a write off.

http://www.wetterzentrale.de/topkarten/fsreaeur.html

http://www.wetterzentrale.de/topkarten/fsreaeur.html

http://www.wetterzentrale.de/topkarten/fsreaeur.html

http://www.bbc.co.uk/wales/mid/sites/in_pictures/pages/snow_february_2007_5.shtml?4

The event was caused by a (channel) low pressure coming up from the south and meeting cold air over us from previous days.

As for SSTs there don't tend to make that much of a difference, with we are quite a bit inland from the NNW winds that tend to being the snow showers here in winter. However apart from one day in Febraury last year, these have failed to deliver for teh past 3 winters.