Sst's And Sea Ice - Trends

[Optimus Prime]

I would actually prefer a warm english channel much of the eastern sea mild then a cold one. During 2003 we had a notable easterly spell which caused some surprisingly deep snowfall around the south east. London recorded 10CM and some parts a lot more. I haven't got the SST's for that period but I expect the sea's were warm around us then to allow a front to develop across the north sea.

If we get warm anomalies with cold air going across it I personally think it increases our chances of a big snow event similer to 1991. If the cold air is coming across cold sea surely there's no convection to allow much of a front to develop

Edited October 4, 2005 by Optimus Prime

[Zerouali lives]

I would actually prefer a warm english channel much of the eastern sea mild then a cold one. During 2003 we had a notable easterly spell which caused some surprisingly deep snowfall around the south east. London recorded 10CM and some parts a lot more. I haven't got the SST's for that period but I expect the sea's were warm around us then to allow a front to develop across the north sea.

If we get warm anomalies with cold air going across it I personally think it increases our chances of a big snow event similer to 1991. If the cold air is coming across cold sea surely there's no convection to allow much of a front to develop

<{POST_SNAPBACK}>

This is the catch 22 situation. Most people on this thread are naturally hoping for a decrease in SST anomalies to promote colder weather. However, as OP has just described, low SST's don't support large convective snowfalls from a continental easterly for example; unlike warmer seas which would allow for a 'lake effect snow' scenario producing heavy snowfalls. So the question is - do we really want below average SST's in the North Sea? Surely we couldn't refuse such a thing?!

[TG312274]

So basically in a nutshell:

We want cold seas in the mid-Atlantic and the Iceland/Greenland area, and warm seas in the North Sea and Channel.

[summer blizzard]

We do not want a cold anomoly in the mid Atlantic as that would favour a Atlantic High, although we do want cold anomolies to soround Greenland and the Bermuda region, we want cold anomolies along the latitude of France as that would favour a southerly tracking Jet Stream, i personally do not care what happens in the English Channel or North Sea.

[Optimus Prime]

i personally do not care what happens in the English Channel or North Sea.

<{POST_SNAPBACK}>

So by saying that you don't want a channel low that can give some tremendous snow cover to the south? A warm sea should allow for channel lows to develope deeper then a cold sea.

[TG312274]

He probably doesn't want a Channel Low to bring snow to the South as he lives near Leeds.

[SMU]

He probably doesn't want a Channel Low to bring snow to the South as he lives near Leeds.

<{POST_SNAPBACK}>

Just bringing back this topic to the title SST's-

Im surprised no-one has mentioned The Current pacific trend is for a Negative PDO- which is in turn good news for us brits- as the severe winters have generally occured in Negative PDO driven Winters...

Steve

Edited October 5, 2005 by Steve Murr

[kold weather]

Hi Steve,yeah thats intresting although worth remembering that most winters in the 80's had a positive PDO and so i suspect that this feature only has a slight influance on our weather but can help to shape our large-scale weather..Also what I've started to nice is that we may have the starts on La Nina prehaps in the Pacific on the last few days worth of SST's.Worth watching that I'd have thought.

Colder SSt's seem to be digging south-westwards towards the U.K as well it seems.

[Glacier Point]

The old conundrum, +ve PNA bad or good for west European winter ?

I think the trend will be very much towards a +ve PNA pattern this winter with large +ve SST anomalies off the NW coast of N.America, colder ones further west and cold anomalies to the south-east around the Caribbean. The NOAA seasonal temp and ppn forecasts seem to bear this out.

The implications of this for us I flagged up yesterday, but in essence a +ve PNA could still be good news IF the sub-tropical jet takes centre stage.

But, I would agree a (strongly) -ve PNA and -ve NAO is thoroughly good news for us, particularly if accompanied by a -ve AO. The situation developing now reminds me of late July with blocking further NE and the Greeland High gaining strength combined with strong ridging over the eastern seeboard of the USA.

GP

[Wayneywoo]

This time last year there was nearly 200,000 square kilometres less Greenland sea ice.

I just get the feeling that something different is gonna happen this year. The SST's are completely different.

Maybe last year something happened that will be used as a start for this winter

I wish I could put a more technical post up like WO or GP but unfortunately I can't so I'm just saying what I think!

:lol:

[Optimus Prime]

What's notably different this year is the Greenland ice sheet is aveage or even above average.

What a turn around from last year!

[smith25]

There abit of a change north of us...Its grown slightly larger in size but has also become less potent. The warm anomoly around the pole has shrunk slightly and the atlantic has more colder pools of water. Still along way to go yet so plenty of changes yet to come.

https://www.fnmoc.navy.mil/products/NCODA/U..._sstanomaly.gif

Very different from this time last year though.

https://www.fnmoc.navy.mil/products/NCODA/A..._sstanomaly.gif

Edited October 7, 2005 by smith25

[Cecil Hogmanay Melchett]

Smith25,you really need to go to ssts anonymous ,ps only kidding,keep up the good work !

[Anti-Mild]

The contrast to last year is very cheering and encouraging. I actually think that the colder areas to the north have become more potent.

I hope to goodness tho, that like Enforcer has suggested, the situation doesn''t unravel come December time and +anomalies take over again and open the door to the 'corridor of death'.   

That is being unduly pessimistic at this stage though and currently signs are still pretty good. The METO forecast, at this stage, gives some backing to optimism too. Also IMO the reverse positon in showing warm atlantic anomalies (in contrast to last year) suggests to me that any HP blocking might not be anchored in mid atlantic like last yr. The METO prediction of colder and drier weather than normal suggests blocking in a more favourable position.

Albeit, there is a long way to go, and yes much could change but so far - pretty good.

Ramp stage 3 at present.

SP

<{POST_SNAPBACK}>

I agree with that prognosis SP. The current SST anomalies are in just the right position for us and are definitely cause for optimism, especially when comparing them to last year.

However, as you say, it is early days yet and lots can happen between now and December. I am reluctant to go to SATSIGS level 3 this early though !

AM

[Big Bear]

I have to admit yes going by where HP was situated last year, the prominent blocking will hopefully occur to our north for the first time in yonks.

Remember HP has a tendancy to develop & settle over cold pools in Winter and warm pools in summer. Hence the mid atlantic/ Azores HP we saw all year this summer.

[John Cox]

Albeit, there is a long way to go, and yes much could change but so far - pretty good.

Ramp stage 3 at present.

SP

<{POST_SNAPBACK}>

Hi SP,

I agree. The SST's anamolies to our north are getting better by the day.

Regards,

John

[Michael Fishermans Friend]

Noticed though that the Eastern seaboard of the United States is very warm in comparison to last year and 'if' there was rapid cooling on land surely this would 'keep alive' LP moving into the GIN sea area in future months, I haven't really studied SST anomolies in previous years but how quick can the transistion take from negative to positive values? But the cool/cold pooling to the north does give us some optimism (at present).

Edited October 7, 2005 by Timmy H

[The Enforcer]

Noticed though that the Eastern seaboard of the United States is very warm in comparison to last year and 'if' there was rapid cooling on land surely this would 'keep alive' LP moving into the GIN sea area in future months, I haven't really studied SST anomolies in previous years but how quick can the transistion take from negative to positive values? But the cool/cold pooling to the north does give us some optimism (at present).

<{POST_SNAPBACK}>

Very quickly. The first week of October 2002 was extremely similar to the current charts, but by November 2002 positive anomalies had replaced the negative anomalies and by the onset of winter 2002/03 they had become massive positive anomalies.

Edited October 7, 2005 by The Enforcer

[Mr Maunder]

The contrast to last year is very cheering and encouraging. I actually think that the colder areas to the north have become more potent.

I think you are right there SP.

There is definately more ice in the Greenland Sea than at the same time in either 2001 and 2002.

Fo this reason alone I remain optimistic that the negative anomalies to the north will remain, although as ever time will tell.

MM

[TG312274]

I noticed on the link to the SST temps site at the top of this page (I think it was a US Navy Weather site? :o ) that there are negative anomalies to our north and positive anomalies to our west. Last year meanwhile it appeared there were positive anomalies to our north and negative anomalies to our west (on the two charts given anyway). Are the two linked in some way? Does -ve anomalies to our north mean +ve to our west generally or what?

[BLAST FROM THE PAST]

Hi SP,

I agree. The SST's anamolies to our north are getting better by the day.

Regards,

John

<{POST_SNAPBACK}>

Depending which chart you use some are more encouraging than others ie look at unysis...terrific. Can't post the link, cr@p at that sort of thing.

BFTP

[BLAST FROM THE PAST]

I'm increasingly confident they will remain too - altho I can well understand Enforcer's significant wariness on the matter. We have certainly 'been there' before and don't want to 'go there' again!! :o  

Somebody (sorry forgotten who ) posted a very impressive temp forecast for the Greenland ice-cap interior of -50C this weekend - which must be fairly unusual for Oct (at least these 21st century days) and assuming it comes off.

Could be another signal that those - anomalies will hold tight this time. I know there has been disagreement about this but I still reckon the GH has held up well and been prominent a lot of the time since Spring.

Reasons to be cheerful

SP

<{POST_SNAPBACK}>

SP

Yes ice retention is apparently much better in that part of the world than of recent times. I am of the opinion that these ssts will hold due to synoptic pattern up there. I am really pleased too that we haven't had the plunge from up there yet too...it would be too early.

BFTP

[Optimus Prime]

SST update;

Things are looking very good indeed. The cold pool around Northern Iceland is very intense. Some 3.0c below average. There are however warm anomalies north of the intense cold around Iceland. The cold seas around the area I would estimate as being larger than the size of India.

So any cold blasts we get are most certainly going to be intensified.

The warm anomalies for the atlantic are much less warm and a cool pool seems to be developing amongst it which I expect will soon develop into a negative anomaly.

Moving onto North America, there are some potent warm anomalies that seem to be hanging around east Canada and the eastern seaboard of America (Particularly potent around the Rhode Island/New York region) while there seems to be a cold pool developing south of that. far north Canada has rather cool seas.

The chuchki sea (Bit between Alaska and Russia) is still very warm and hasn't shown signs of cooling. Perhaps slightly cooler than a week ago.

So overall, exciting to the north of us and I don't see them - anomalies dissapearing into the near future. otherwise it's on the warm side.

[summer blizzard]

The current northern hemisphere sea surface temperature anomolies are very encouraging, although i would like to see the Chucki Sea cool down soon.

The anomolies in the Pacific Ocean are also encouraging, the cold anomoly to the south west of the British Isles will favour a Omega block and therefore a posotive PNO in conjunction with the posotive anomoly near the north eastern United States however i would like to see the posotive anomoly in the middle of the Pacific Ocean move west as in its current location, it will not have much effect on the location of the Jet Stream as it will bericate before reaching the United States, due to the fact that the warm anomoly to the north east of the United States is more intense than the cold anomoly to the south west of the United States, i expect the Omega block to be displaced further west than normal resulting in a colder than average United States with a posotive PNO due to central and eastern United States being colder than average rather than the usual west-east split or displaced eastwards block resulting i warmer than average coinditions for the United States.

As for the anomolies in the Atlantic, the intense cold pool to the east of Greenland will promote nothern blocking, along with the posotive anomoly in the middle of the Atlantic Ocean, which will promote a southerly tracking Jet Stream and the cold anomolies in the southern Atlantic Ocean, these are all encouraging signs.

Several things which could be improved are:

1) the negative anomolies in the southern Atlantic Ocean could be more widespread and intense

2) the posotive anomolies in the middle of the Atlantic Ocean should not be more intense than the cold anomolies either side of it

3) if a cold anomoly develops in the middle of the Atlantic Ocean, that is okay as long as the warm anomoly is beow the cold anomoly

[The Enforcer]

Looking at the differences between 6th and 7th October charts I see the very first signs of the cold anomalies being eroded away.