Autumn And Winter Lrfs

[Turnedoutniceagain]

Time for "Autumn Discussion" to appear on the Forum Board ??

C'Mon Mods, another week or so & TEITS will be spotting Easterlies at T760+ :lol:

[Anti-Mild]

Time for "Autumn Discussion" to appear on the Forum Board ??

C'Mon Mods, another week or so & TEITS will be spotting Easterlies at T760+

Autumn Discussion should appear on 1st September. As for an Easterly, I'm sure I saw one on the GFS FFFFFI :lol: :lol: !!!

[John Cox]

Autumn Discussion should appear on 1st September. As for an Easterly, I'm sure I saw one on the GFS FFFFFI :lol: :lol: !!!

A field day it will be for TEITS and all us SACRA members, sooner than usual

[Damien]

Well for those who want some easterlies at T2688 I *may* have some good news tomorrow. :lol:

Thursday is the big day this week. And it's not to do with NCEP. Let's all cross our fingers. :lol:

[Anti-Mild]

Well for those who want some easterlies at T2688 I *may* have some good news tomorrow.

Thursday is the big day this week. And it's not to do with NCEP. Let's all cross our fingers.

If this is the 'worm guy' I'll be less than impressed :lol: :lol: !

Or have you been doing some grebe studying?

AM

[Thundery wintry showers]

I pray to God to not have a winter like that. In Oslo were i live february 1990 set a record for a winter month that I hope never will be beaten(even with GW):

A mean temperature of 3,4 C (7,4 above 61-90 mean). Forget frost and snow in Britain and even in most parts of Norway with that kind of winter.

Was January 2005 similarly warm? According to the Weather Log, Oslo's mean temperature was a full 7.4C above the 61-90 mean in that month.

It seems to me that the warmest conditions in Oslo happen from two setups- either the south-westerly gale conveyor belt (as in February 1990) or high pressure over the S or SW of Britain, sending anticyclonic westerly winds over to Norway with air originating in the tropics.

[tinybill]

Well for those who want some easterlies at T2688 I *may* have some good news tomorrow. :lol:

Thursday is the big day this week. And it's not to do with NCEP. Let's all cross our fingers. :lol:

well i hope the east winds dont come just yet as next mouth on the east coast we got the highest tides for20 years coming, with all the damage to our coast line at the moment that will mean huge problems, in norfolk, suffolk

[Glacier Point]

Always possible Tim - but a couple of reasons I don't think we'll see it this year - 89/90 was at or near the peak of the solar cycle and sea surface anomolies were very different:

http://www.osdpd.noaa.gov/PSB/EPS/SST/data....90.anomaly.gif

Back in 89/90 there was a developing La Nina in the pacific (quite a potent one I believe) - and also the cold North Atlantic, combined with a warm Southern North atlantic - classic indicator of a positive NAO.

This winter we may have a weakish El Nino, and I suspect a warm North Atlantic (50-60 degrees latitude), combined with a cooler (relative) southern north Atlantic.

http://www.osdpd.noaa.gov/PSB/EPS/SST/data...t.8.15.2006.gif

Okay so we're still 3-4 months away from Winter and there's plenty of time for the sea temp profile to change as we go through Autumn, but right now I'd say we're looking at more blocking this winter.

:lol:

I very much agree with these sentiments. As things stand, several factors look favourably placed:

1) the warm north Atlantic and cooler central Atlantic bipole - the residual SSTA built up over several months now will not change for the current Winter so a -ve NAO will be a stronger prospect allowing for the leading of the Artic Oscillation.

2) Solar minima.

3) Weaker Pacific Jet and much more amplified jet pattern across the hemisphere.

Taking these into account, I would suggest at this early stage, the probabilities of a large pool of cold air developing to our east are reasonable, and crucially with no Pacific Jet to blast it away, we might stand a better chance of landing the easterly this time round.

GP

[SMU]

I very much agree with these sentiments. As things stand, several factors look favourably placed:

1) the warm north Atlantic and cooler central Atlantic bipole - the residual SSTA built up over several months now will not change for the current Winter so a -ve NAO will be a stronger prospect allowing for the leading of the Artic Oscillation.

2) Solar minima.

3) Weaker Pacific Jet and much more amplified jet pattern across the hemisphere.

Taking these into account, I would suggest at this early stage, the probabilities of a large pool of cold air developing to our east are reasonable, and crucially with no Pacific Jet to blast it away, we might stand a better chance of landing the easterly this time round.

GP

Yes & Thats what all the climate models are currently pointing to with an associated warm pool in the atlantic- (Prob the intense WAA)

S

[summer blizzard]

I thought that i would post my preliminary CET estimates for the winter period at this stage.

November: 3.9C - Coldest since 1925 (Based on teleconnections forecast to be released in next few days)

December: 3.4C - Coldest since 1996

January: 2.6C - Coldest since 1997

February: 3.1C - Coldest since 1996

March: 2.6C - Coldest in the past centuary

Winter CET: 3C

[SMU]

I've said several times (probably on the wrong thread lol) that this coming winter could well take the progression of the last winter a stage further with the pacific jet playing ball much better and allowing cold pooling to advect further west.

To me, things look very nicely placed overall at this stage, and whilst it is still only August, optimism remains and with the summer heat bubble burst, I am looking forward in earnest now to the shorter days and waiting for the clearer winter signals to shape up for what may be in store.

The increasing dominance of a blocked pattern over last 18 months, reduced zonality with only brief non Corridor of Death zonal spells and weaker penetration of atlantic activity too much beyond the meridian over that time (look at the record over last winter and this year for example), and the SSTA set-up and solar minima are reasons to be cheerful at this time.

Tamara

This is what we want to hear!

:lol:

Tamara

A cold polar vortex has already developed early this season in the Artic....

Here illustrated on the 12Z ECM for the Artic- day 3

There is some sub -10C air at the heart of that which is around 6-10 degrees cooler than normal....

S

[BLAST FROM THE PAST]

Yes & Thats what all the climate models are currently pointing to with an associated warm pool in the atlantic- (Prob the intense WAA)

S

Steve and GP

I was mentioning in another thread, and indeed Steve you responded kindly to one post that the SST set up [apart from the NE USA/Newfoundland warm pool] looks to me a better scenario than last year. Interesting too is the cold pool developing to our north in the high arctic which Carinthian is monitoring. I have posted/still believe that we have a 'real' shot of a princely cold spell in Nov and Dec at this stage. I think this longterm synoptic change some of us called last year is very real now...and some of those are on this page :lol:

BFTP

[SMU]

Steve and GP

I was mentioning in another thread, and indeed Steve you responded kindly to one post that the SST set up [apart from the NE USA/Newfoundland warm pool] looks to me a better scenario than last year. Interesting too is the cold pool developing to our north in the high arctic which Carinthian is monitoring. I have posted/still believe that we have a 'real' shot of a princely cold spell in Nov and Dec at this stage. I think this longterm synoptic change some of us called last year is very real now...and some of those are on this page :lol:

BFTP

indeed .... its only a matter of time...

S

[smith25]

indeed .... its only a matter of time...

S

Is polar vortex going to make you change your winter forcast?

[Snowyowl9]

A cold polar vortex has already developed early this season in the Artic....

Here illustrated on the 12Z ECM for the Artic- day 3

There is some sub -10C air at the heart of that which is around 6-10 degrees cooler than normal....

S

This does look promising as much as I remember the cold winters of the 80`s.

I don`t expect any like that but slightly colder and snowier than last year will do me.

:lol:

[reef]

A little tounge in cheek, but Im moving to a house in October without central heating fitted, so you can almost guarantee it will be the coldest winter for many years :lol:

In all seriousness, the polar vortex and cold pool to our direct north is indeed rather early. Lets just hope it stays there this winter, instead of being stuck over Greenland until March like the last.

Edited August 16, 2006 by reef

[ScandiHigh]

Was January 2005 similarly warm? According to the Weather Log, Oslo's mean temperature was a full 7.4C above the 61-90 mean in that month.

It seems to me that the warmest conditions in Oslo happen from two setups- either the south-westerly gale conveyor belt (as in February 1990) or high pressure over the S or SW of Britain, sending anticyclonic westerly winds over to Norway with air originating in the tropics.

Hi TWS

According to Met.no(The Norwegian MET office) January 2005 was 1,7 (6 C above the 61-90 mean:)

http://met.no/observasjoner/oslo/2005/januar/index.html

However, the first 18 days had a mean of 3,5 C, but a more anticyclonic pattern the last half prevented that kind of figures for the month as a whole.

You are right about warm conditons in Oslo in winter. Those conditions can often bring fohn to Southeast Norway, with temperatures of 10 C or more.

I think you will find a high correlation between winter temperature in Norway and Britain. We are in the same boat. The 88/89 ,89/90 and 04/05 winters were extremely mild winter in your location too? At the other end of the scale, I see often references to the january 87 episode in this forum. January 10th 87 has entered the record books in Oslo as well. Not for the lowest minima, but for lowest maxima ever recorded. Until that that day the lowest maxima ever recorded in a day was -18,5. On Jan 10th the max temp was -20,5 in Oslo. I have looked at the 850 HPA temps for that that day and it is beyond anything in the GFS archive. -25C air over Oslo!

Cold setups may bring -20C air over southern Norway, but this was -25! Will we ever(in our lifetimes) see that again?

[kold weather]

I'm very intrested in that polar vortex, though prehaps its a touch to early to read into that as one decent string of NE moving ex-hurricanes could well get rid of it as its stil la fdairly small feature on the grand scale of things. The one thign this polar vortex may also do this Autumn is to make it quite wet, like a proper Autumn with plenty of unsettled weather about.

I am pretty sure that the polar vortex is as cold as it is right now for 2 reasons. the first being the solar min is present right now and the second is the lack of any tropical cyclones getting into the jet stream which has meant the amount of heat getting northwards has also been reduced, esp when you compare it to recent years.

I've not really got much of a clue how this winter will turn out, I'm still watching the tropics for the most part however I am noting that the SOI continues to remian very negative on the 30 day rolling and the SSt's are now becoming favorable for El nino to pop its head by the end of the year offically.

Still I dare sahy if the polar vortex can keep in a similar position till October any northerly may well have some bite about them, hopefully!

[The Enforcer]

As ever, there are always promising signs on paper, but will these actually translate into anything useful in the core winter month of January? There is normally at least one factor that refuses to play ball.

There is also a problem with wintry conditions pitching up in early/late winter. When you see a chart with south-westerlies on it you get wind, rain and silly nightime temperatures. Anticyclonic charts produce fog and frosts. When you get a northerly or easterly scenario, it always looks terrific on paper and GFS starts churning out those precipitation charts showing the whole of the UK in a blanket of snow. In reality, all that happens is that it feels cold and raw. Not what it says on the tin.

[Anti-Mild]

As ever, there are always promising signs on paper, but will these actually translate into anything useful in the core winter month of January? There is normally at least one factor that refuses to play ball.

There is also a problem with wintry conditions pitching up in early/late winter. When you see a chart with south-westerlies on it you get wind, rain and silly nightime temperatures. Anticyclonic charts produce fog and frosts. When you get a northerly or easterly scenario, it always looks terrific on paper and GFS starts churning out those precipitation charts showing the whole of the UK in a blanket of snow. In reality, all that happens is that it feels cold and raw. Not what it says on the tin.

Last winter the main stumbling blocks seemed to be a raging Pacific Jet Stream and a less than impressive cold pool at high latitudes. This year if the forecasted weak El Nino event happens we can expect the Jet to track out of the Southern US - good news for a possble -ve NAO so that takes care of the Jet :lol: ! The cold pool is better now than at the same time last year, although it is still very early and things can change rapidly!

I would expect the frequent blocking of the past 18 months to continue, so it is probably just a case of geting the HP in the right place for us - hopefully a Scandi or a northerly misplaced AH linked with a GH please !

[Anti-Mild]

Yes, AM the Pacific Jet was the problem for us during the early to middle part of the winter, as it precluded the height rises over Greenland that we needed to get the cold continental air our way. Another problem were shortwave features developing to our North and North West which I believe were related to the amount of energy that remained in the system from the late Summer warmth.

As Enforcer alludes, getting cold is one thing, getting widespread snowfall is quite another and so many factors need to come together at the same time.

I must admit that I would love a heap of snow but I would prefer a February 1986 style month; not a great deal of snow but very cold. Even if a huge HP was parked over us for most of the winter bringing nothing but sunny days and cold frosty nights I would be happy with that. It's just mild and wet that I hate!

AM

[reef]

Last winter the main stumbling blocks seemed to be a raging Pacific Jet Stream and a less than impressive cold pool at high latitudes. This year if the forecasted weak El Nino event happens we can expect the Jet to track out of the Southern US - good news for a possble -ve NAO so that takes care of the Jet :lol: ! The cold pool is better now than at the same time last year, although it is still very early and things can change rapidly!

I would expect the frequent blocking of the past 18 months to continue, so it is probably just a case of geting the HP in the right place for us - hopefully a Scandi or a northerly misplaced AH linked with a GH please !

Problem is the jet coming out of the southern US is all good and well, but if the jet ends up over us we stay in the mid-90s pattern of SW-NE travelling depressions, the sort of pattern which gave stinker winters like 1988/89, 1989/90 and 1997/98.

Looking back at the El Nino years, I still remain to be convinced it can be a good thing for our winters. The following winters had an El Nino:

1957/58 - close to average

1965/66 - mild

1972/73 - very mild

1977/78 - mild

1982/83 - mild

1987/88 - very mild

1991/92 - mild

1992/93 - mild

1994/95 - very mild

1997/98 - very mild

2002/03 - mild

The coldest of those winters had a CET of 4.10°C (Manley), and only 1957/58 was marginally below average. Im not sure how snowfall levels were in those winters, though the recent post-87 in that list were all relatively poor by memory.

Edited August 17, 2006 by reef

[BLAST FROM THE PAST]

I'm very intrested in that polar vortex, though prehaps its a touch to early to read into that as one decent string of NE moving ex-hurricanes could well get rid of it as its stil la fdairly small feature on the grand scale of things. The one thign this polar vortex may also do this Autumn is to make it quite wet, like a proper Autumn with plenty of unsettled weather about.

I am pretty sure that the polar vortex is as cold as it is right now for 2 reasons. the first being the solar min is present right now and the second is the lack of any tropical cyclones getting into the jet stream which has meant the amount of heat getting northwards has also been reduced, esp when you compare it to recent years.

I've not really got much of a clue how this winter will turn out, I'm still watching the tropics for the most part however I am noting that the SOI continues to remian very negative on the 30 day rolling and the SSt's are now becoming favorable for El nino to pop its head by the end of the year offically.

Still I dare sahy if the polar vortex can keep in a similar position till October any northerly may well have some bite about them, hopefully!

KW

Maybe you can enlighten me, I thought that this year was predicted to be a horror hurricane season with the East Coast USA getting battered. Where are these hurricanes? I mean it seems a rather modest season so far

BFTP

[kold weather]

Blast, yeah its been pretty sedate so far, and pretty clsoe to average as well, mind you we still ar eonly at the start of the peak and ther eis still time for the hurricanes to get going, indeed the 06z GFS suggests the exact sort of pattern that gives the east coast of the USA a scare:

http://www.nco.ncep.noaa.gov/pmb/nwprod/an...en_l_loop.shtml

[Anti-Mild]

Problem is the jet coming out of the southern US is all good and well, but if the jet ends up over us we stay in the mid-90s pattern of SW-NE travelling depressions, the sort of pattern which gave stinker winters like 1988/89, 1989/90 and 1997/98.

Looking back at the El Nino years, I still remain to be convinced it can be a good thing for our winters. The following winters had an El Nino:

1957/58 - close to average

1965/66 - mild

1972/73 - very mild

1977/78 - mild

1982/83 - mild

1987/88 - very mild

1991/92 - mild

1992/93 - mild

1994/95 - very mild

1997/98 - very mild

2002/03 - mild

The coldest of those winters had a CET of 4.10°C (Manley), and only 1957/58 was marginally below average. Im not sure how snowfall levels were in those winters, though the recent post-87 in that list were all relatively poor by memory.

The winters that you listed all experienced fairly strong El Nino levels. In fact in terms of the ONI (Oceanic Nino Index) the lowest level in any of those winter months was 0.5c in February 1988 which followed on from a weak El Nino. Most of the others were up above 1.5c

http://www.cpc.ncep.noaa.gov/products/anal...ensoyears.shtml

Given that the prediction is for continued neutral levels followed by a weak El Nino event, looking back through that table the closest parallels for this years data are:

1967 - Winter CET 67/68 = 3.5c

1979 - Winter CET 79/80 = 4.6c

1981 - Winter CET 81/82 = 2.6c

1986 - Winter CET 86/87 = 3.5c

1990 - Winter CET 90/91 = 3.0c

Of these analogues, 1986 and 1967 are probably closest to this year whereas 1979 is a bit tenuous.

TBH, I'd take a winter CET of 3.5c right now!