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Hi Daisy- Ive just seen this post Via a PM from Paul- cant do anything today- but I will put something together tomorrow for you- best regards Steve

Hi rollo - I havent got time to do a long reply now- However I will have a look later- and post up a few charts from the archives etc-- S

And with the aforementioned section highlighted the pinnacle of a High Amplitude jet its the rare evolution of A 4 WAVE PATTERN... ( the left one) This basically ensures that Nothing changes fast.... S

WW- welcome first of all- Ive not looked at South Wales- it seems to have not been covered today- anyway- I 'Think' looking at the 3 big hitters 12z runs that when tonight Fax come out at 11pm they will be heavily modifed- So lets wait for them and we perhaps can begin to take a closer look at a regional level.... best regards S

Perhaps I went a bit OTT with the -30C- anyway- realistically we have a potential -12C windchill This is the NWS image for Windchill- assume the surface temps are 0c which is ~ 30F- Go down the 30F coloumn and go to 40 MPH sustainded winds but gusting around 60MPH- Celsius to Fahrenheit Conversion Chart Celcius converter At 30F with that wind we are looking at -12C- thats still one hec of a windchill- if you start getting surface temps of below say -5C - which isnt out of the question in scotland then windchill values could be as low as -20C which is cold wherever you are .... regards Steve

Here we go on the radio link- Top dog from NCEP!!!!! S

Also one important piece of information is as of today for the first time since Mid Dec 2004 the Northern Hemisphere Sea ice cover has recovered to Normal values- Best Regards Steve PS Current live winter link- Click listen now Link Larry cosgrove top american pro met Top dog now on from NCEP- Wheres damien??? Talking about NAO... LISTEN IN.......

This loop is most useful= SST loop- S

Morning GP The Winter Forecast is released today- that one will be very interesting- I reakon the Parameters will be -PDO, NAO swings to Neg POS- No sustained periods either way, ENSO- La Nina- And in terms of the States- a definate Midwest Winter/ Northern Plains- with below average Snowfall for the north-East- Strong Alaskan PV with contined storms till start of Dec where it all begins to drop in to the Midwest- Hurricane season Not seeming to figure on that one- NO apparent analogues- and a bit of an Accuweather Bashing!!! regards Steve

Evening ALL-- Some Important Changes over the last few weeks in terms of SST' Patterns- PDO- With the Strong polar Vortex over the Gulf of Alaska in recent weeks- upwelling continues in the North East pacific- This has developed more Cold anomalies which will act as a buffer against the warmer anomalies to the South which stretch back to the Japanese Coast- This Colder Upwelling continues to drop the PDO further into Negative- In terms of the US The theaory in terms of PDO being Neg will be a Strong Pacific Jet - Trough on the West Coast- Ridge on the East - Coast- This is indicitive of a Neutral to NEGATIVE PNA Pattern NOT POSITIVE- Greenland / Labrador as well has seen Stormy weather lately- especially across the Southern side-Again we have had Cold upwelling Developing dropping the SST's into -VE anomalies- This again will act as a buffer against the warmer Surface currnets pushing North- Should this upwelling continue this will push the Colder SST's South- which is a better picture in terms of moving towards a complimentary SST' pattern for a Negative NAO- Looking at ENSO regions 1/2 & 3/4 a La Nina is developing- and is worth keeping an eye on- just based on this sentence - ANY FORECAST basing its forecast around the parameter of a Neutral ENSO is WRONG and needs to be updated- ( This includes any forecast planning a +VE PDO, +VE PNA- Its Not going to Happen........ ) As for the NAO- Medium term outlooks look for significant drops over Early December, Mid Dec & Early Jan, also March- ( Based on MJO oscillation) Finally- if anyone uses the PNA & NAO data PLEASE use the CDC Data NOT the CPC data- the CPC Methodology is different and not valid- ( I seem to remember someone mentioned the other day the NAO looked wrong) Best regards Steve

Evening John- Ive been following a forecast for the NAO that relates to the cycles of the MJO- Seeing as theres nothing in the models showing- The next forecast for a significant Negative NAO pattern to develop is the last day or so of Nov into the first week of Dec - which the forecaster is saying this will usher in some severe wintry weather... We Shall see..... Steve

Afternoon All- Once again for the endless references for Queries regarding where we do and dont want warm & Cold pooling to be observed here is the Correlation chart for SST best fit pattern for a NEGATIVE NAO pattern This is the Strongest signal that we can use to Forecast NAO at the moment- Remember its NOT just about the GIN corrisoor- its Global especially taking into Consideration the Negative PDO- If you refer to the Current Unysis Map- The pacific side is almost Spot on- even down to the developing Cold pool of Japan- Atlantic side whilst NOT quite perfect EVERY day is seemingly inching towards an almost perfect analogue.... Much reason to be happy inspite of some of the more recent Weather and postings on the board Steve

This thing is all but stalled at the moment- Hows this for unlucky-( and a bit worrying) My X-Girlfriend is currently in Cancun with her friend from wk- on her friends honeymoon as she split up with her other half- Havent heard from her in 3 days- Nor has her sister- Lets hope the direction changes soon as.... S

Evening All- I will have a look at tracks and get back to peeps- Until then I will leave you with an image of Cozumel One for the holiday broschure S

this is what it looks like.... but as youve seen them im saving the space... thanks sb Steve.....

HI GW- I havent spent much time looking at Wilma Today- been on the Winter section- The current track is as Mondy says a dirct hit on Cozumel ( Slightly west of NHC predictions)- the Upper level ridge will begin to weaken and allow the turn away from the Yucatan- If there is a direct hit in the Yucatan especially further south where there is higher terrain then Wilma will struggle and may be severely downgraded- which will be good news for Florida- However a little furtehr east across the water and she will escape unscathed- Its a margin of error of only a 100 miles or so.... Also the ERC is pretty much complete now- look for a re-opening of the eye and re-intensification back to Possible Cat 5 status- Also watch for a slowdown of forward motion- a precursor to a change in direction.... Such a close call this one... S

Here is what a full phase will look like- Phase And here are the current just updated tracks... These are the ones to observe for accuracy- as they handle phasing better GFDI GFTI GFDL CONU NGPI Steve

Its funny you should post that link SB- I chat to that Professional forecaster sometimes Via PM- He is Excellent- but his forecasts are for America im Afraid..... S

Evening All- Well I did say last night I thought it was ghonna bomb... but bloody hell- Some of you may remember me talking yesterday about the phasing of the pacific trough and causing devestation in the North east- I was going to pass further comment on this based on the 12z runs but one of my colleagues has already blogged it- Phase blog S

Good evening All- Well this is my first real serious look at a Long range outlook- The forecast Period covered is December/January/Febuary ( Abbrieviated DJF) and covers the 'expected' Northern hemispehere atmospheric flow patterns generated from my source data- with obvious particular attention to North-Western Europe- This Forecast WILL NOT attempt to Pin down certain dates over the Winter as from my own experience this is still beyond our reach- The forecast is driven by Oceanic & Atmospheric data which drive the Teleconnection patterns- For the record it may be pertinent to remind people that ALL Patterns discussed here are born out of Oceanic/SST trends - ( This means they start in the ocean & Work their way up into the Atmosphere) this is with the exception of the AO which starts in the atmosphere and works its way downwards- The basic rationale for ocean observations for climate research and forecasting is straightforward. Basically, the upper 10 feet of the ocean has the same heat capacity as the entire atmosphere and therefore has a tremendous influence on both short- and long-term air temperature changes. Likewise, the ocean holds a significant amount of carbon dioxide, which can influence future atmospheric levels of this greenhouse gas. Observing these properties of the ocean and incorporating relevant data into models—like what is done in weather forecasting—is essential to the prediction of our future climate (whether it is the onset of the next El Niño or the longer term decadal changes linked to the AO, PDO, and NAO). Therefore, the accuracy of future climate forecasts will depend on improvements to our ocean observations (especially temperature, salinity, and currents) within the upper layers of the ocean. Before we get into the finer detail of the decadal oscillations we must first draw a line in the sand.... The starting point for any preliminary forecast would be one of assesment - Data that is supported by evidence of continual global trends will be a good overall precursor to the overall temperature anomalies against the Mean for the forecast period- For this there are some statistics & graphs that demonstrate this adequatly with this particular one driving the point home- 0 The current overall Temperature anomaly against the mean average is upwards of 1C - that may seem insignificant- but bring this back to the marginality of our Wintry events and this is the route number 1 cause of the problem- Should we wish to correlate our own CET in terms of a similar plotted graph I would suggest that it is very simlar in trend with perhaps a bigger upward deviation of anomaly since the late 80's- Also If I take September 05 as a snapshot of the current global picture then things are pretty much as expected in terms of warming- if a little more pronounced- I dont want to really go into the Global Warming discussion- this is because the data shows the trends and for the purpose of the forecast AGW or NO AGW its irrelavent-However as a caveat to the last statement I would like to briefly explain why the rate of warmth experienced by the UK has been exaggerated since the late 80's- especially through the mild winters of the Nineties- Its our dependancy on high lattitude Blocking to interupt the westerly Zonal flow of the jet to induce cold spells- especially ones that last longer than 2 days- Globally speaking the KEY driver of this is the Polar Vortex and its strength- The strength of the Polar Vortex has a direct effect on the gradients driving the Jet stream- The Simple key is the Stronger the Vortex the steeper the gradients and stronger the Jet stream- Moving a stage further- the Strength of the PV ( Polar Vortex ) is driven by the Temperature in the Stratosphere- the COLDER that is the Stronger the Vortex and vice versa- The graph illustrated below is the Stratospheris Temps anomaly from 1978 to current- highlighted in BOLD is the link to AGW... The Stratospheric temps- The figure above shows the monthly temperature deviations from a seasonally adjusted average for the lower stratosphere - Earth's atmosphere from 14 to 22 km (9 to 14 miles). Red is an increase in the temperature from the average, and blue is a decrease in temperature. The large increase in 1982 was caused by the volcanic eruption of El Chichon, and the increase in 1991 was caused by the eruption of Mt. Pinatubo in the Philippines. November 2000 was the coldest month on record for stratospheric temperatures. The long-term downward trend in lower stratospheric temperatures is believed to be the result of ozone depletion (primarily), and to a lesser extent the increase in carbon dioxide concentrations due to the burning of fossil fuels. If we now put the Strong Polar vortex into context and transpose this into jet stream terms- the jet has undergone some serious investment from the Stratosphere- and the trend continues- In terms of visibility and a quantifiable measure we use the teleconnection 'AO' and for those unsure of the technical description here it is- So Summary for the AO- remember (Globally speaking) A stronger Vortex means a higher +VE phase and less in the way of high lattitude blocking- >>>>>> Less Meridional Flows >>>>>> Less Southward Cold Air penetration.With the global anomaly explained as well as the Stratospheric anomalies layed out you would say that the odds against getting ANY MONTH below average let alone a WINTER below average are Stacked WELL against us- Well Maybe NOT so- The stratospheric temps have remained fairly constant over the last few years however there have been some significantly warmer pockets appearing over the poles- this will help slow the PV down...... So... Apart from the AO this winter and indeed ones to follow there are other influences / oscillations at a Global & Local level that may help to bring some of the equilibrium back to the Uk's temperature anomaly - At the very worst to level out against the average global +VE anomaly- and perhaps better still below the average +VE anomaly- For this Studying the ENSO, NAO, PDO, and to a point QBO Patterns is essential..... We move on..... The Overall Controlling Ocean Current in terms of effecting global patterns is the ENSO ( El Nino Southern oscillation) The current ENSO pattern is NEUTRAL and from the NOAA forecast suite without delving into to much detail the summary is.... 'ENSO-neutral conditions are expected during the next 3-6 months.' When ENSO is Neutral we move onto the Secondary big Oceanic driven Patterns that effect us- The PDO ( The Pacific Decadal Oscillation) and NAO ( North Atlantic Oscillation) are both net end results of Oceanic Current movements and circulations- Before I go into detail regarding these Its a pertinent point to remind people that when these teleconnections phase strongly together either + or - VE then these are the most extreme winters - this is of course for both Mild or Cold conditions- The NAO ...... So many posts on the weather forums refer to this oscillation, However for those still unaware exactly what is it a brief overview and a link to a more detailed explanation- The basis of my forecast for NAO this Winter is based around 2 Caveats- 1) Tropical Convection 2) SST anomalies So then... Tropical Convection- ( And also remember SUMMER Convection can leave a WINTER SST Blueprint - some members here keen to dismiss ideas of Summers, Autumns and Winters are not linked) Let me start by saying that this does not establish black and white rules by any means, and this stuff should be used with caution like anything else, but all other things being equal, there does appear to be at least a hint of correlation here. What has been examined is how tropical convection (NOT necessarily tropical storms and hurricanes, but convection in general) affects the circulations in the Atlantic, which in turn can affect the SSTs, which in turn can have an effect on the atmosphere. They used OLR anomalies to measure convection, then used computer modeling to simulate how enhanced areas of convection alter the atmospheric circulations. What they found was that enhanced convection (decreased OLR-Outgoing Longwave Radiation) in the Caribbean and over central Africa lead to a weakening of the trade winds via an anomalous low in the central Atlantic (the enhanced convection in the Caribbean even led to Rossby-like waves that propogated northeastward toward Spain), especially when combined with less convection over South America along and just south of the Equator. This indicated a northward shift in the ITCZ and led to an alteration of the SST pattern in the autumn giving the tripole of warm water in the tropics, cooler water in the central Atlantic, and warmer water in the north Atlantic. Their studies showed that this pattern (which is the earmark of the -NAO) generally persisted into the early winter. When the results of the modeling were tested by comparing the modeled pattern to actual patterns during -NAO early winters, there was a good degree of correlation shown, but it was hypothesized that other factors (ENSO, etc) could override this. Composites of the OLR anomalies for the 15 years which had the strongest -NAO and a composite of the 15 years which had the strongest +NAO. Keep in mind decreased OLR means increased convection-!!! Jun/Aug Composite Neg NAO were- 54,57,59,62,63,64,65,67,68,70,76,77,78,84,95 Composite Pos NAO were- 73,74,80, 82,83,87,88,90,91,92,93,94,98,99,04- The composite maps for the -NAO years match the hypothesis very well,with enhanced convection in the Caribbean and over central Africa, as well as decreased convection over central South America. In addition, you can see that this isn't related to the hurricane season per se, as there are some high number hurricane seasons that actually had less convection overall, so one cannot simply go by hurricane number. Again, keep in mind the theory here. Summertime convection alters the Atlantic circulation, which alters the SST pattern in the Autumn, and the SSTs, all other things equal can leave an imprint on the atmosphere into the early winter. If you then transpose the same composite years across to the 1000mb plots for climo anomalies you can see the low anomalies in the -NAO years from 20-30ºN in the Atlantic, indicating the reduction in the trade winds, just as hypothesized in the Hurrell paper. The +NAO years have no such low anomaly in that region. There are some other stark differences as well, but we want to remain focused on the Atlantic to decide if the aforementioned ideas have any merit. It does indeed appear that the ideas do have some value, barring any other stronger outside influences, as we have established not only a correlation, but have identified a logical reason why this could work, and even shown how computer modeling came up with a similar look when initialized with the enhanced convection in the appropriate locations. So what does this have to do with now? Well, before I get into that, let's look back to last year. The hurricane season of 2004 obviously was quite active, which led some to call for a -NAO overall for the winter. Yes, we did get the massive block late winter and Late Feb into March, but overall, it was a +NAO winter The summer 2004 OLR anomalies will show the decreased convection over central South America, but notice how despite the active hurricane season, convection in the vicinity of the Caribbean and over central Africa was actually lower, which is the opposite of what is observed in the -NAO years. In fact, the 1000mb anomalies also more closely match the +NAO years. Looking closely at 2005- We have highly enhanced convection in the Caribbean, enhanced convection over central Africa, and decreased convection along and just south of the equator in South America, though not quite as concentrated as some of the -NAO years. So far, that alone would indicate a better chance for an early winter -NAO than a +NAO, but again looking at the Atlantic circulation measured by the 1000mb anomalies- Again, this too looks more like the -NAO years than the +NAO years. It will be interesting to see how this affects the SSTs as we head through the autumn. If it affects them in the ways mentioned above, then we should indeed get an early winter -NAO this year. But one must always consider the fact that not all -NAOs are alike, cand some do not even some with a snowy pattern. That said though, I think all snow lovers would prefer to take their chances with a -NAO than a positive one...... Some caveats... Most of the -NAO years also occurred when the negative phase of the PDO predominated, and that phase of the PDO also correlates to some similar looks, so again, I would say use this with a degree of caution, but I think that since the pattern in the Atlantic obviously has more to do with the NAO phase than does the Pacific, the correlation isn't entirely unusable, even though I think there are connections between the two........... 2) After the initial comparison for Tropical Convection is digested the output from this in terms of Autumn SST Patterns is for a pretty Sharp SST correlation to Support -NAO years.... Seeing as many many people quote SST anomalies on a daily basis I have produced from the CDC site a correltaion map which lends itself perfectly for a -NAO... The above correlation map from CDC of the SST anomaly pattern for -NAOs.(NEG) Focusing on the Atlantic. Notice the correlations? A negative NAO correaltes best with an Atlantic setup where, there are above normal SSTs in the tropics to 20N. Below normal water above that up to around 50N. Another belt of above normal water, above this north of 50N, to south and west of Grenland. And another band of below normal SSTs above this north of Iceland and east of Greenland. The setup is very similar to what is in the Atlantic right now, EXCEPT there is warm water currently off the NE US.However this is slower being replaced by Colder waters sinking south- iF these turns to negative anomalies, then it is almost a perfect -NAO setup in the Atlantic.... As I mentioned earlier phasing with the PDO WHEN it is Negative can create Very extreme conditions- First of all a breif overview of the PDO-again another Oceanic Oscillation- Again referring to the CPC site I have produced the 500 Mb Geopotential Height anomalies for both +VE & -VE PDO Phases- The key here is the Height rises encouraged over Greenland and Lower anomalies over the Iberian penninsula inline with the Negative PDO phase- Whilst the PDO is NOT the driving factor for Greenland in context with Phasing with -VE NAO years its crucial- Ive posted the link to the TABLET form both PDO & NAO below- ( Again the Key Months are Nov,Dec,Jan NAO Tabular averages PDO tabular averages If you look at the PDO Cycle the biggest -VE period was the late 40's early 50's through the 60's & 70's- since then Positive on the whole-Especially the last 4 years- ALL Positive.... until last year- 3 months of neg and a trend this Autumn towards the Neg- this will hopefully spell the PDO beginning to oscillate to a cool phase...... We will need to keep an eye on that PDO...... With these 2 Big teleconnections summarised I just want to add my feelings around the Scale of any -VE NAO /PDO's- and how this will effect us- Firstly I would Say both Teleconnections are in a mode of Change towards Negative trends - However values below -1 index of NAO are still considerred NEUTRAL.... The PDO is pretty Static at the moment which means no real movement away from the -VE phase- This means that Should things remain fairly static in terms of SST anomalies or continue to gather a little pace in our favour things look set for a higher than recent chances of at least ONE sustained Cold spell- This is Where People like the MET-Office have upgraded to Amber Alert Because the likleyhod is increased- Sadly though Im NOT expecting this year to be the Bumper Year- Im going for 07/08 on that one- WIth Hopefully A phase of Sunspots/NAO & PDO all strongly -VE- Also the key withe NAO will not be so much height rises over Greenland, but significant height decreases over the iberian peninsula allowing for Southerly advection into the UK- What I Am expecting is ONE month to be the Winner in terms of Breaking the chain of Above averages- This Im expecting to be December or Jan- Based on the early phasing of NAO & PDO- and the displacement of the PV ....... Should the Phasing have been Stronger -VE then maybe I would have gone for more- BUT this is a even larger teapot and one cant get away from those land based Temperature anomalies- What I expect this Year in terms of pattern development is ( Broad Scale) November- Cyclonic - The energy in the Jet Still to Strong for High lattitude blocking ( due to the Tropical Storm season being Active) with this probably being the wettest Month of the Autumn for the Uk> Above average Rainfall for the UK Above average CET for the UK~ 7.5C final December- A Split- between Cyclonic & Anti-Cyclonic, the key here will be the beginnings of the transfer south of that Polar front, I dont expect anything FULL on for Dec, but a couple of Potent northerlies to wet the appetite.... Approximate Level Rainfall for the UK Above average CET for the UK ~ 5C January- Anti-cyclonic Im looking at Jan to buck the trend of recent Winters- Gone is the storm season & so fingers crossed will be the Omni present Icelandic low- Im looking for Greenland/East zone of +VE Heights and a Good repetative feedback for 7-10 days of Cold air, maybe more- Below average Rainfall for the UK below Average CET for the UK ~ 3C Febuary- Anti-Cyclonic The early Winter SST movements will determin this one- I would at this stage go for a month of 2 halves- Northerly Blocking V Southerly Blocking- again NO strong Jetstream to mention of, however Im wary that repetative Greenland blocking also ends with Bartlett Blocks... So Below average Rainfall for the UK Above Average CET for the UK ~ 4C Ok that just about wraps it up- hope this sheds some light as well on the often Misquoted Met office review of the -NAO as it doesnt Guarentee anything- Many regards to you all... Steve As Sf says all this of course this is mere conjecture.......

They are 100% linked... Steve

Evening All- A large part of My winter outlook covers the SST anomalies... I will edit it Now and post the finished work around 10pm this evening.... Steve

Thanks for the comments All- Again a Total phase with the pacific trough in the mid west is needed for Total devestation- A possible Sub 950 Mb low in the Norther East will mean Flooding for sure.... My updated discussion.. Regards Steve

Sub 900 Mb Soon to come can she break the 885 Mb barrier????? S

Morning All- OMG total bomb 70 millibar over night...... Another sub 900 again.... S