October CET

[summer blizzard]

Tinybill: 6.4C

Joneseye: 7.5C

Optimus Prime: 9.3C

Tinybill: 9.4C

Snow-Man2006: 9.5C

Hiya: 9.8C

Beng: 9.9C

Shuggee: 10C

Convection currents: 10.1C

Red Raven: 10.1C

Steve Murr: 10.2C

Stormchaser1: 10.3C

Summer Blizzard: 10.4C

Senior Ridge: 10.5C

Medway Frezee: 10.5C

Wilson: 10.5C

WindWatcher: 10.6C

Intrepid: 10.7C

Snowmaiden: 10.7C

Stargazer: 10.7C

Reef: 10.8C

Wellington Boot: 10.8C

AtlanticFlamethrower: 10.8C

Roger J Smith: 10.9C

PhilipEden: 10.9C

Skiwi: 10.9

Viking141: 11C

Lesta_snow: 11C

The Abominable Snowman: 11C

Tesaro: 11.1C

Anti-Mild: 11.2C

Mr Sleet: 11.2C

ChrisL: 11.4C

Kold weather: 11.5C

Mr Maunder: 11.6C

Snowyowl9: 11.7C

Stricklands: 11.7C

Dawlish: 11.7C

Parmenides3: 11.8C

Rollo: 11.9C

Somerset Squall: 12C

Stephen Prudence: 12C

The PIT: 12C

Bham Chris: 12.1C

Robbie: 12.1C

Bottesford: 12.2C

Megamoonflake: 12.3C

Summer of 95: 12.3C

Windswept: 12.4C

Timmy H: 12.4C

Suruike: 12.5C

Tugmistress: 12.6C

Snowprincess: 12.7C

Scorcher: 12.7C

Glacier Point: 12.9C

West is Best: 13.4C

Mike W: 13.6C

Wilson, the 1970-2000 average is most commonly used and is 10.4C, therefore your CET estimate would be 10.6C, would you like to stay with the 10.3C or shall i ajust it for you.

Edited October 2, 2006 by summer blizzard

[VillagePlank]

On the basis of this:

I am revising my Oct CET upwards to be 10.5C

[Gray-Wolf]

I think, purely on the basis of recent trends and a quick glimpse at the GFS, that I'll plump for 13.2*c.

Again it'll be the night-time mins that count and not so much outragously high day-time temps

[Cymru]

I'll go for 12.4, though I do suspect that it will come out slightly higher than that.

[Guest Mike W]

As it's only the 3rd, if possible I would like to change mine to 9.8 please.

[SNOW-MAN2006]

Is a mild october a good thing? :lol:

No it isnt i cant wait for the cold to arirve but what i am stating is that the models have changed to what they where predicting the other day (which was cooler weather) but now it looks like it is staying milder... :blink:

SNOW-MAN2006

[Stratos Ferric]

Having been preoccupied with far more weighty matters for a few weeks now, a quick perusal of the Atlantic SSTs this morning has come as a big shock; the Atlantic is widely 2-3C above par. The hemispheric surface anomaly is fairly extensively warm or very warm, particularly so in locations that might otherwise be the source of cold air. The jet looks very energised, to the extent that it is splitting yet again in the E hemi; in recent years that has tended to indicate mild weather, pushing the PF well poleward around our longitude.

Looking at the numbers, October is the one month of the year that had, particularly up until last year, and after July, most resisted the year round warming: in the previous ten years October was outside +/- 0.5C on the upside only three times, and on the cold side twice. The rolling average 30 for October is around 10.7, pulled up smartly by last year's sudden rise. Back to back warm Octobers are very unusual, though I made a similar observation about the sequence of warm Septembers!

Ordinarily I'd punt lower than this, but on the basis that I should have followed my hunch in September, rather than the numbers, and given the the fundamentals have not changed, then I could easily see this month getting close to record territory again, certainly in the 2-2.5C above par band. Therefore I would project:

12.9C

[Stratos Ferric]

11.2 C for me.

Reflecting on the year so far, it is quite obvious that the relatively blocked nature of our weather is playing havoc with monthly CET's.I wouldn't be surprised if the year as a whole ( which is the really important measure) continued the recent downward trend in CET.

That would require a OND combination cooler than seven of the last ten, and all that against a general trend of warming: the most recent ten year average is fully 1.0C warmer than that for the ten years ending 1995. If this year does come in cooler than last it's going to require something very unusual in the modern autumn, and something spectacular given the current warmth in surrounding waters. Even if it does come in lower, as in the past three years, the drop will be well iside the margins of rounding errors. I think it looks like coming in warmer now, probably by 0.2-0.3C, and a new record cannot be ruled out.

Not really, if the pattern runs the same, the pattern runs the same. There can be no analogue at all otherwise.

Either analogues have value or they do not, they can't have some value for part of the year and not for others.

Yes and no. If I turn my boiler on for an hour in summer the ouse ends up a lot warmer than it does if I turn it on for an hour in winter. Direction of flow is only part of the story, the SSTs for the source, and along the track of the cold air are also important. I'd hasard that c.f. the late 60s our SSTs are now 1-2C warmer than they were then. On the basis same synoptics won't necessarily produce weather cold enough for widespread snow. In any case, this is just another example of the seasonal pressure build regarding prospects for a cold winter, and nowadays it's about the only example of a cold high pressure that we ever get.

[Thundery wintry showers]

A bold prediction by Stratos, though I wouldn't rule such a high outturn out.

I went for 11.9C, though I think there's more chance of it being higher than lower.

[Mr Sleet]

That would require a OND combination cooler than seven of the last ten, and all that against a general trend of warming: the most recent ten year average is fully 1.0C warmer than that for the ten years ending 1995. If this year does come in cooler than last it's going to require something very unusual in the modern autumn, and something spectacular given the current warmth in surrounding waters. Even if it does come in lower, as in the past three years, the drop will be well iside the margins of rounding errors. I think it looks like coming in warmer now, probably by 0.2-0.3C, and a new record cannot be ruled out.

Yes and no. If I turn my boiler on for an hour in summer the ouse ends up a lot warmer than it does if I turn it on for an hour in winter. Direction of flow is only part of the story, the SSTs for the source, and along the track of the cold air are also important. I'd hasard that c.f. the late 60s our SSTs are now 1-2C warmer than they were then. On the basis same synoptics won't necessarily produce weather cold enough for widespread snow. In any case, this is just another example of the seasonal pressure build regarding prospects for a cold winter, and nowadays it's about the only example of a cold high pressure that we ever get.

Judging by your record in predicting the CET, which is about as good as mine, I suggest we wait and see.

Edited October 3, 2006 by Mr Sleet

[Glacier Point]

Therefore I would project:

12.9C

Copycat! In essence we agree that little has changed since September so why not a much above return.

The SSTA reanalysis late '60s vs 2000s

clearly major differences there, most notably all of the Atlantic, most of the Pacific and the polar region.

The western Atlantic is notable because in terms of differentials, the situation is not as different compared to say the Pole - we have replaced cold water anomalies with neutral ones whilst the warm anomalies have become increasingly stronger north-east of Newfoundland more particularly in the last two years in this area.

A crude inference from this would be that most CETs should follow the warming suit although sudden and often dramatic reversals in CET over the last two years stand as anomalies to this uniform warming. If October followed the predicted outcome, I for one would not be that quick to draw conclusions of Nov - Dec- Jan - Feb following the trend. If anything, I think it would inspire some quiet confidence in at least one of these months producing a big turnaround. This I think is where the real skill in the CET trophy will be displayed - sucessfully predicting that below average month.

Edited October 3, 2006 by Glacier Point

[Thundery wintry showers]

SF makes a very good point about SSTs btw; I think they may well have contributed to why August 2006 wasn't a cold month despite having frequent north-westerly winds, for example. They may also explain, in part, why for example the "westerly" cold snap of 18 January 2005 didn't produce as much snow as similar synoptics, and 850hPa temperature values, did in for instance January 1984.

I find it hard to see where significantly below average temperatures come from at the moment; probably a long-draw northerly would suffice, but there isn't much evidence of any such synoptic happening for a while.

[parmenides3]

I would go with SF on this one: I was tempted last week to go high, but everyone would have put that down to some kind of personal prejudice, so I got conservative all of a sudden. mean + 2-2.5C is certainly feasible.

:)P

[Stratos Ferric]

Judging by your record in predicting the CET, which is about as good as mine, I suggest we wait and see.

I think we're all waiting and seeing; that is the nature of this game. I was amused last month, and before, by Philip's ability to project very accurately the surface synoptic mean - far far in excess of anything anyone else on here could muster I suspect - yet not convert that into a temperature that was, on the face of it, as accurate. The best anyone can hope for is to be in the ballpark; any more than that is just good luck really.

What might be an interesting analysis is to see whether the average of our averages is any good, or of some permutation of people.

Copycat! In essence we agree that little has changed since September so why not a much above return.

The SSTA reanalysis late '60s vs 2000s

clearly major differences there, most notably all of the Atlantic, most of the Pacific and the polar region.

The western Atlantic is notable because in terms of differentials, the situation is not as different compared to say the Pole - we have replaced cold water anomalies with neutral ones whilst the warm anomalies have become increasingly stronger north-east of Newfoundland more particularly in the last two years in this area.

A crude inference from this would be that most CETs should follow the warming suit although sudden and often dramatic reversals in CET over the last two years stand as anomalies to this uniform warming. If October followed the predicted outcome, I for one would not be that quick to draw conclusions of Nov - Dec- Jan - Feb following the trend. If anything, I think it would inspire some quiet confidence in at least one of these months producing a big turnaround. This I think is where the real skill in the CET trophy will be displayed - sucessfully predicting that below average month.

I have to say I did allow myself a smile when I read the thread this morning, but only after posting my projection, and saw your analysis.

Not sure I concur re the sudden changes in CET though. I assume you mean monthly, in which case the only particularly cold outliers in the past four years have been March this year, and October 2003. I do agree that the cleverness in projecting is spotting the outlier, particularly at present on the downside, though doing so without always predicting low is the essence. This site has more than a few people who shout out loud on their own behalf when they call successfully a cold spell, without observing that they made the same call unsuccessfully several times previously.

[Thundery wintry showers]

I'm not sure if I can remember all of my predictions correctly, but I can at least vaguely recall the predictions I made. Here are the comparisons since

June 2005: prediction 14.3, actual 15.6 (+1.3)

July 2005: prediction 16.5, actual 16.9 (+0.4)

August 2005: prediction 16.5, actual 16.2 (-0.3)

September 2005: prediction 15.2, actual 15.2 (0.0)

October 2005: prediction 12.4, actual 13.1 (+0.7)

November 2005: prediction 8.2, actual 5.8 Manley, 6.2 Hadley (-2.4 or -2.0)

December 2005: prediction 5.5, actual 4.7 Manley, 4.4 Hadley (-0.8 or -1.1)

January 2006: prediction 2.8, actual 4.3 (+1.5)

February 2006: prediction 4.3, actual 3.7 (-0.6)

March 2006: prediction 5.5, actual 4.9 (-0.6)

April 2006: prediction 8.2, actual 8.6 (+0.4)

May 2006: prediction 11.8, actual 12.2 (+0.4)

June 2006: prediction 14.7, actual 16.2 Manley, 15.9 Hadley (+1.5 or +1.2)

July 2006: prediction 17.6, actual 19.7/19.9 (+2.2)

August 2006: prediction 16.9, actual 16.1 (-0.

September 2006: prediction 15.5, actual 16.7 (+1.2)

Overall, on average I underestimated CETs by 0.3C and was on average 0.9C out from the actual outturn.

[SteveB]

10.2c for me.

[Stratos Ferric]

SF makes a very good point about SSTs btw; I think they may well have contributed to why August 2006 wasn't a cold month despite having frequent north-westerly winds, for example. They may also explain, in part, why for example the "westerly" cold snap of 18 January 2005 didn't produce as much snow as similar synoptics, and 850hPa temperature values, did in for instance January 1984.

I find it hard to see where significantly below average temperatures come from at the moment; probably a long-draw northerly would suffice, but there isn't much evidence of any such synoptic happening for a while.

The one hope I can see is a sustained continental feed, NE/ENE would be required. That, though, would need a HP to our N, which would in turn require either a low energy PFJ, or one displaced well south. It's the latter two that I cannot see being sustained, and whilst ever we have so much energy in the jet that it continues to branch to our north we aren't going to get HP stationary there; small intermittent mobile features forming where and if the flow loops back are possible - and have been a particular feature of the past 2-3 winters that I don't recall previously (though this may just be because until recently we didn't have readily available surface and upper data to link cuase and effect) producing occasional small "shallow" HPs, but these have been mobile and with a tendency to drift.

[Optimus Prime]

According to the latest GFS run by the 8th October will stand at 12.4c. 2.0c above average for the whole month or around 0.9c above for the first half.

[acbrixton]

Looking at the numbers, October is the one month of the year that had, particularly up until last year, and after July, most resisted the year round warming: in the previous ten years October was outside +/- 0.5C on the upside only three times, and on the cold side twice.

12.9C

Pedants' Corner: SF I think you mean June and not July...

Regards

ACB

[Polar Continental]

Ok, here’s my October prediction, a fairly typical autumnal month ahead i think, 10.7c about average.

Paul

[ukmoose]

Warm ground, warm seas nothing much in the way of change in the near future with the wind direction not changing much between west and south and no particularly cold nights o bring the mild days down - I'll go for a mild 12.9 degrees C.

ukmoose

[Stratos Ferric]

Pedants' Corner: SF I think you mean June and not July...

Regards

ACB

No, I did mean July. Yes, this year was exceptional, but in the past ten years it has come in more than 0.5C below the current 30 yr average four times, and above by 0.5C or more four times. Octobber runs it close at a 2-3 spilt prior to this year. Not other month comes close on this measure.

[Terminal Moraine]

As I just can't see October being below average after such a warm September I'll go for 11.9c

T.M

[summer blizzard]

Tinybill: 6.4C

Joneseye: 7.5C

Optimus Prime: 9.3C

Tinybill: 9.4C

Snow-Man2006: 9.5C

Hiya: 9.8C

Mike W: 9.8C

Beng: 9.9C

Shuggee: 10C

Convection currents: 10.1C

Red Raven: 10.1C

Steve Murr: 10.2C

SteveB: 10.2C

Stormchaser1: 10.3C

Summer Blizzard: 10.4C

Mammatus: 10.4C

Senior Ridge: 10.5C

Medway Frezee: 10.5C

Wilson: 10.5C

WindWatcher: 10.6C

Intrepid: 10.7C

Snowmaiden: 10.7C

Stargazer: 10.7C

Paul Carfoot: 10.7C

Reef: 10.8C

Wellington Boot: 10.8C

AtlanticFlamethrower: 10.8C

Roger J Smith: 10.9C

PhilipEden: 10.9C

Skiwi: 10.9

Viking141: 11C

Lesta_snow: 11C

The Abominable Snowman: 11C

Tesaro: 11.1C

Anti-Mild: 11.2C

Mr Sleet: 11.2C

ChrisL: 11.4C

Kold weather: 11.5C

Mr Maunder: 11.6C

Snowyowl9: 11.7C

Stricklands: 11.7C

Dawlish: 11.7C

Parmenides3: 11.8C

Rollo: 11.9C

Terminal Moraine: 11.9C

Somerset Squall: 12C

Stephen Prudence: 12C

The PIT: 12C

Bham Chris: 12.1C

Robbie: 12.1C

Bottesford: 12.2C

Megamoonflake: 12.3C

Summer of 95: 12.3C

Windswept: 12.4C

Timmy H: 12.4C

Cymru: 12.4C

Suruike: 12.5C

Tugmistress: 12.6C

Snowprincess: 12.7C

Scorcher: 12.7C

Glacier Point: 12.9C

Stratos Ferric: 12.9C

Ukmoose: 12.9C

Gray-Wolf: 13.2C

West is Best: 13.4C

Mike W: 13.6C

I just though that i would say that people predicting 12.9C are unlikely to be correct, as two years having the same October CET is unprecidented.

If October had the same drop as August from July, the CET would be 13.2C.

Edited October 3, 2006 by summer blizzard

[Mammatus]

A typical Autumn month ahead I feel. Pleasent spell next week, cooler after mid month. 10.4C

Mammatus