Sea Surface Temperature And Sea Ice Trends(2)

[summer blizzard]

Looking at the latest sea surface temperature charts, the things that spring out at me are:

1) The general split in sea surface temperature anomolies in the Meditteranian Sea still remains with the west being warm, and the east being cold...

This favours the downstream high over western Europe but a trough over Eastern Europe which opens up the possibility of retrogression.

2) Tripole pattern in place and developing...

The GIN area is now almost entirely average to below average favouring a Polar Vortex to the east of Greenland and continued ice development

3) Hudsons Bay looks to be cooling, leading to ice buildup.

Once Hudsons Bay is frozen, this will encourage the develpment of a surface high, reinforcing the Greenalnd High and pushing the Jet Stream south.

4) The mid and low lattiude central Pacific has developed a warm anomoly at low lattitude and cold anomoly at mid lattitude favouring a northerly Jet Stream in the central Pacific, the western Pacific is also developing cold anomolies at mid-lattitudes...

This will encourage a positive PNA pattern and may also indicate a weakening of the westerly QBO because warm water at low lattitudes indicates easterly trade winds.

5) The anomolies across the whole Pacific continue to favour a neutral PDO value.

I believe that the current negative PDO is what is causing a weakening of the QBO.

6) El Nino looks to be fairly static with weekly drops and rises...

I expect anomolies to peak this month and slowly reduce over the next few months.

[Iceberg]

Alot going on today, but looking at recent velocities around the NAD, it seems pretty fast flowing, anyone like to volunteer how this will effect the weather in NW europe.

The NAD is clearly viewable on this chart but seems very large around as it passes Scandy.

Matt

[AtlanticFlamethrower]

Alot going on today, but looking at recent velocities around the NAD, it seems pretty fast flowing, anyone like to volunteer how this will effect the weather in NW europe.

The NAD is clearly viewable on this chart but seems very large around as it passes Scandy.

Matt

Here we are - latest chart. Plus Gulf Stream forecasts from Mercator.

Edited November 24, 2006 by AtlanticFlamethrower

[summer blizzard]

Can't make any detailed posts for another week or two, but a strong thermal gradiant is setting itself up in the mid-Atlantic, expect some very deep storms on a fairly southerly track to develop during the last ten days of the month.

[beng]

http://weather.unisys.com/surface/sst_anom.html

For anyone interested, there's been a definite weakening of El Nino in the area just off the S American coast - I would presume this may have implications for the PNA pattern through the winter - as well as the jet strength.

Also - hopefully we'll see a weakening of the warm pool south of Newfoundland as the cold pool over NE America moves out to sea.

[Stratos Ferric]

Alot going on today, but looking at recent velocities around the NAD, it seems pretty fast flowing, anyone like to volunteer how this will effect the weather in NW europe.

The NAD is clearly viewable on this chart but seems very large around as it passes Scandy.

Matt

I'd be less worried about speed than I would temperature.

[summer blizzard]

Signs of a more positive NAO signal as we head towards the new year.

[Gavin P]

LOL! Thats grim news. Thats when most of us thought winter might actually kick in! Is this going to be "The Year Without A Winter?"

[summer blizzard]

My internet may be back online tonight or tommorow so i will post in detail then, however with the main atlantic cold anomoly now above the warm anomoly, that points towards a more positive NAO, though combined with the cold anomoly to the east of Greenland, this may point towards a milder AND snowier outcome for this winter.

[summer blizzard]

Starting in the Pacific, the thermal gradiant increases the further east you go, which is what is causing the neutral PNA however the Atlantic is more complex as cold anomolies have developed underneath warm anomolies in the north Atlantic supporting both a large thermal gradiant but crucially a southerly tracking Jet Stream in the western and central Atlantic however with a warm anomoly downstream of the cold anomoly, this will only serve to strengthen a high pressure area around Spain, in the Mediteranian, we are looking at warm anomolies however there are much warmer anomolies in the Baltic region and around Scandinavia with a cold anomoly between Iceland and Norway.

Based on sea surface temperatures alone, i would say that the Beast From The East will arrive with vengance towards the end of January, but only in Europe and that while anticyclonic, the best we should hope for is south easterliesuntil at least February.

Edited January 11, 2007 by summer blizzard

[summer blizzard]

Pacific, stronger thermal gradiant in western Pacific and continuing into central Pacific, eastern Pacfic setup supports Alaskan ridge and low pressure to the south of the ridge despite negative PDO continuing and setup favouring negative PNA, as a result, as a result, expect neutral to positive PNA.

Atlantic, setup in the Pacific favours a negative NAO with Greenland blocking and Azores Low, though it also favours a European Ridge, so expect south easterlies to dominate first ten days of February, no complete undercut of European block, but also expect two periods of retrogression into central Atlantic and northerlies.

Edited January 23, 2007 by summer blizzard

[summer blizzard]

Pointers for mid February..

Strong signs of amplification in the Pacific with a split Jet Stream.

Major storms in the south west of the USA due to Jet Stream becoming confluent west of the USA.

Positive PNA signiture.

Western Atlantic trough.

Western European blocking.

In summary, i suspect the Jet Stream will have too much energy to undercut the European block completely however i think that there will be an atempted easterly around mid-February.

[summer blizzard]

I will go into detail later, however sea surface temperatures now support blocking over Greenland and Scandinavia from the 20th onwards, with a resultant southern Jet Stream and cold, cold, cold!!!!

[summer blizzard]

Looking at the current chart, there is a strong signal for a strong Pacific and Atlantic Jet Stream, with the greatest amplification occuring in the western Pacific and eastern Atlantic however there.

Unfortanutely for the UK, being on the edge of the decelerating Jet Streak, this is likely to lead to a Decemeber 2006 senario with a block over the UK itself, though i would expect the Jet Stream over Aisa to be fairly amplified.

Once again, i feel that this is a setup which would be conducive to above average warmth in the northern hemisphere as a whole with well above average anomolies over the USA.

In summary, look out for pressure to build over the UK around the 10th, though given the current anomolies, i would expect the high to sink rather than retrogress afterward.

[summer blizzard]

I will go into detail later, however sea surface temperatures now support blocking over Greenland and Scandinavia from the 20th onwards, with a resultant southern Jet Stream and cold, cold, cold!!!!

Just noticed that i posted this, and look how close we actually came.

Looking at the latest sea surface temperature anomoly chart, you can see that the strongest thermal gradiant appears to be in the central Pacific, however the Jet Stream over the eastern Pacific and the USA looks to be more amplified for around the 15th, in favour of a slightly positive PNA however the thermal gradiant in the western Atlantic still looks strong decreasing the further east in the Atlantic that you go however with the UK on the front of a decelerating Jet Stream, i expect that the high pressure over the British Isles around the 10th, will have moved eastwards slightly, bringing a warmer air flow to the British Isles.

[summer blizzard]

Looking at the latest sea surface temperature anomoly chart, you can see that there is a fairly weak thermal gradiant in the western Pacific, however there is a strong thermal gradiant in the central Pacific though the Jet Stream once again amplifies over the USA with a ridge over the central plains and a trough over the eastern USA and western Atlantic with the Jet Stream decelerating further in the central Atlantic, causing a pressure build over both Greenland and Europe, which would support a ridge just to the south or south west of the British Isles resulting in sunny, dry but rather average temperatures with the ridge most likely retrogressing towards Greenland afterwards around the 25th would be my guess...

On the chart above, i have annotated two areas...

1) This is the area where i expect a mean area of low pressure, in the Gulf Of Alaska

2) This is the area where i expect the mean ridge to form, in the central Atlantic

If i remember correctly, an Alusian Trough and Atlantic Ridge are two hallmarks of a La Nina pattern, indicating the rapid onset of La Nina which is already showing up in the Tropical Pacific.

In summary, between the 20th and 25th, i expect a strong Pacific Jet Stream, though a rather amplified global pattern and a ridge to the spouth or south west of the British Isles, though pressure to be above average meaning that the wind direction could range from southerly to north westerly dependant on how far east the Azores High ridges.

[summer blizzard]

Looking at the latest sea surface temperature anomoly chart which may correspond to the setup around the 28th, you can see that there is a weak thermal gradiant in the western Pacific, though the thermal gradiant once again increases in the central Pacific before becoming more amplified to the west of the USA, allowing a weak ridge over the central plains with low pressure to the west and east of the USA, however the thermal gradiant will once again increase in the western and central Atlantic however it will once again decelerate supporting a mean ridge over Europe.

[summer blizzard]

Looking at the latest sea surface temperature anomoly chart, you can see that there is a weak Jet Stream in the western Pacific and that the thermal gradiant increases in the central Pacific however there are signs of a more amplified Jet Stream developing with quite a negative PDO (Pacific Decadel Occilation) signiture, though once again the thermal gradiant weakens in the eastern Pacific with a mean hemispheric trough in the Gulf Of Alaska, this lends itself to a rather flat but weak Jet Stream over the USA with a ridge over the central Plains and a trough either side, however once in the western Atlantic, the thermal gradiant increases once again before weakening in the central and eastern Atlantic, this is a complex pattern because i expect the upper flow to be south easterly while i expect the highest thickness levels to be just to the south or south west of the British Isles, at anyb rate, i expect the first few days of April to usher in extreme warmth relative to average and possibly thundery.

The chart below shows where i think the mean hemispheric ridge and troughs will be...

[summer blizzard]

In summary, look out for pressure to build over the UK around the 10th, though given the current anomolies, i would expect the high to sink rather than retrogress afterward.

It looks like i called the building of high pressure correctly, however the high pressure now looks to retrogress.

Edited March 14, 2007 by summer blizzard

[summer blizzard]

As you can see from the chart above, i expect the mean hemispheric trough to be in the Gulf Of Alaska and the mean hemispheric ridge to be in the central Atlantic, this is a pattern which supports a neutral to negative PNA over the USA and a very amplified setup in the central and eastern Atlantic, with low pressure to the west of Europe and a ridge over western Europe providing the conditions for a Spanish plume or extreme heat.

Given the setup five days ago was similar, i would say that there is a high chance of the first ten days of April being the warmest on record.

[reef]

As you can see from the chart above, i expect the mean hemispheric trough to be in the Gulf Of Alaska and the mean hemispheric ridge to be in the central Atlantic, this is a pattern which supports a neutral to negative PNA over the USA and a very amplified setup in the central and eastern Atlantic, with low pressure to the west of Europe and a ridge over western Europe providing the conditions for a Spanish plume or extreme heat.

Given the setup five days ago was similar, i would say that there is a high chance of the first ten days of April being the warmest on record.

The problem at the moment of predicting a spanish plume and a record warm first 10 days of April is that the heat simply isnt there yet to tap into. Even way out to T+180, the majority of Spain is still under 20°C at the surface, with the 5 and 10°C 850hPa isotherms well back into Africa. A look at April 1st 2006 for example shows the 15°C isotherm already over southern Spain and a large 20+°C pool of 850hPa air over Northern Africa, just not the case at the moment. What you're suggesting is akin to a Siberian blast in mid-November when there is no cold pooling to be seen, its just far too early.

Thats not to say we couldnt get some settled anticyclonic weather with higher temperatures that way.

[The Enforcer]

Look at those current North Sea temperatures. No wonder Hedon is struggling to get a decent covering of snow - again.

[reef]

Look at those current North Sea temperatures. No wonder Hedon is struggling to get a decent covering of snow - again.

They will really make their effect known when the wind swings to to east of North tomorrow. Not only will we have rogue warm sectors to deal with but SSTs are well over 2°C above average. Look at the same time last year compared to now, theres a huge difference:

2006:

2007:

[The Enforcer]

I dread to think how warm the seas around our shores will be in about 6 months time. If there's dark greens and bright yellows all over the place on the anomaly maps then I won't be expecting much of a winter (again).

[Thundery wintry showers]

It's a bit over-simplistic to say we need a cold summer to keep those SST anomalies down; the reason why this winter has seen such high SST anomalies is the persistence of anomalous warmth. Yes, Summer 2006 contained exceptional heat in June and July, but it was also followed by a record-breaking autumn with a notable lack of cold snaps, and Winter 2006/07, while not record-breaking, was exceptionally mild.

1976 contained a record-breaking hot summer, but a cold cloudy autumn followed, and so the hot summer did not prevent December 1976 and January 1977 from containing noteworthy cold spells.

1995 was quite a close analogue to 2006 in terms of seasonal temperatures; spring was close to average, summer much above, and autumn also much above, but cold weather in early December was enough to send those SSTs plummeting.

We can have a warm summer and still end up with much lesser anomalies for 2007/08; the only pre-requisites there are that we don't end up with a very warm autumn, and early winter as well.