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Gavin P

Nao Forecast For Winter 2012/2013

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A according to Matt Hugo, the EC seasonal forecast update signals a -ve pressure anomaly to the NW of the UK, meaning a +NAO, ultimately meaning wet, windy & mild.

Very early days but the current signs don't seem to be good for Winter 2012/13. Cold weather lovers may well have to pay for this cool Summer in 5/6 months time!

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Very early days but the current signs don't seem to be good for Winter 2012/13. Cold weather lovers may well have to pay for this cool Summer in 5/6 months time!

Unfortunetly not.

As Matt Hugo has said, the EC Seasonal output back in March did forecast the current +ve pressure anomaly we have now to our north west correctly, and it has been upgraded from system 3 to system 4 ( ie higher res ), so it shouldn't be ignored.

This and the QBO do forecast a rather mild and wet winter. However, at this stage, we obviously do have plenty of time.

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Very early days but the current signs don't seem to be good for Winter 2012/13. Cold weather lovers may well have to pay for this cool Summer in 5/6 months time!

That is actually debatable.

The -PDO which seems to be persisting bodes well.

The -QBO could peak as late as September (or now) so winter will be neutral.

The +MEI (El Nino) is unlikely to be strengthening through winter and is not a bad thing necessarily anyway.

Ultimately depends on which of those signals is the most powerful but i would be leaning towards a -AO in December and January at this stage.

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That is actually debatable.

The -PDO which seems to be persisting bodes well.

The -QBO could peak as late as September (or now) so winter will be neutral.

The +MEI (El Nino) is unlikely to be strengthening through winter and is not a bad thing necessarily anyway.

Ultimately depends on which of those signals is the most powerful but i would be leaning towards a -AO in December and January at this stage.

Agreed, 2009/10 winter had a strong Nino and it was the coldest for 30 years, thank god there wont be a significant Nina event this winter, anything around neutral ENSO or above will do for me, i know this is not massively scientific but if you look at the ENSO signal for the last few winters then one would be forgiven for thinking that La Nina is what has given us the shocking last winter and a half.

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just a hunch with no scientific reasoning whatsoever.... NAO negative going into autumn, an indian summer on the way me thinks....then turning positive till January, wet windy early winter... then something a little more seasonal.... Negative NAO from January onwards...as I said no reasoning just a hunch and gut feeling.

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It does seem at this stage that the jet stream is heading north over the next week or so giving us more typical summer conditions. I am starting the think we will end up with another indian summer like that we have had over the last 6/7 years again, as a strengthing Azores high begins to appear. I really don't understand why people are already going for a average/above average winter in terms of rainfall and temperature. I could really see a possible repeat of 2009 (But not to the same extent) What do you guys think?

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Have been looking at the quarters since 1950 which have seen at least 2 months 1.5C or more below the 1981-2010 averages.

Data indicates that actually El Nino is the better bet for a cooler Q4 and Q1 with a transitional QBO (it must be a miracle but that is the conditions expected in the upcoming winter).

Raw data is below.....

oct: 10.7

nov: 7.1

dec: 4.6

jan: 4.4

feb: 4.4

mar: 6.6

jan

1952

1954

1955

1959

1963

1966

1977

1979

1980

1982

1985

1987

1997

2010

feb

1954

1955

1956

1963

1968

1969

1970

1978

1979

1983

1985

1986

1991

1996

2010

mar

1951

1955

1962

1969

1970

1971

1975

1976

1979

1980

1984

1985

1986

1987

2006

oct

1952

1955

1964

1974

1980

1981

1992

1993

2003

nov

1952

1962

1966

1967

1969

1985

1988

1993

2010

dec

1950

1952

1961

1962

1963

1968

1976

1981

1995

1996

2009

2010

q1

1954*: e1

1955**: l2

1963*: l1

1969*: e2

1970*: e1

1979**: e1/+1

1980*: e2/-1

1985**: l1/+1

1986*: e1/+1

2010*: e2/-2

70% El Nino

60% +QBO

q4

1952**: e1

1962*: l1

1981*: e1/-1

1993*: e2/-1

2010*: l2/+2

60% El Nino

66% -QBO

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http://jisao.washington.edu/pdo/PDO.latest

Confirmed - 4th longest -PDO streak (one more month puts us into 3rd, a couple of months puts us into second).

The comparable periods are 1970-1972, 1961-1963 and 1948-1951.

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After this awful summer I hope we get another mild winter, last winter was lovely with just the one short lived cold spell

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Well the summer been so crap lets hope the winter makes it up with lots of snow and cold.

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After this awful summer I hope we get another mild winter, last winter was lovely with just the one short lived cold spell

I find it interesting how much the Brits expect in winter because that 'short lived cold spell' delivered a 12 day mean below 0C, not short at all historically.

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After this awful summer I hope we get another mild winter, last winter was lovely with just the one short lived cold spell

Be prepared for people to quickly put you down in the winter season like people but cool lovers down during the summer - because you're in the very small minority.

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The current IOD maps for winter (December to February) suggest it to be a drier than average again for many parts

tprep.glob.DJF2013.1jul2012.gif

Temperature wise some parts of the north west, scotland and northern ireland are below average but for england and wales were average or just slightly above average

temp2.glob.DJF2013.1jul2012.gif

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A drier than average near average temperature winter will do me just fine smile.png

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I find it interesting how much the Brits expect in winter because that 'short lived cold spell' delivered a 12 day mean below 0C, not short at all historically.

Yes, last winters 'one cold spell' was for England a preety potent one all the same with a mean below 0 degree over a quite lengthy 12 day period and not the 3-4 day cold spells we endured through most winters from 07/08 through to 08/09. I think it will be forgotton quite quickly unfortunately because of the severe lengthy cold spells in late Nov - Dec 10 and more generally mid dec - mid jan 09/10. It was also a proper wintry spell with snow on the ground for quite a number of days and a notable freezing rain event took place.

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February 2012 - snow lying on the ground for more than a week here - temps down to -12 or -13C at Church Fenton - actually Church Fenton was -12C at 2am in February at one point - cloud ruined it - could have gotten seriously low.

It was more of a southern cold spell though.

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Some interesting early thoughts and signs from Matt Hugo concerning the upcoming winter:

http://t.co/k67pnkvR http://t.co/KaGaRjuB

ECMWF seasonal update is out covering D/J/F & has a -ve pressure anom to the E of the UK, with potential ridging to the W...Troughing to the E in winter isn't a bad thing and the +NAO pattern isn't as strong as the July update with temps near/slightly below avg

There is also a strong signal in the ECMWF seasonal for higher pressure over the poles and hence a -AO pattern is evident by the looks.

Seasonal ECM update is interesting esp D/J/F for N Hem with a clear signal for a +ve pressure anom over the pole -AO etc

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Some interesting early thoughts and signs from Matt Hugo concerning the upcoming winter:

http://t.co/k67pnkvR http://t.co/KaGaRjuB

ECMWF seasonal update is out covering D/J/F & has a -ve pressure anom to the E of the UK, with potential ridging to the W...Troughing to the E in winter isn't a bad thing and the +NAO pattern isn't as strong as the July update with temps near/slightly below avg

There is also a strong signal in the ECMWF seasonal for higher pressure over the poles and hence a -AO pattern is evident by the looks.

Seasonal ECM update is interesting esp D/J/F for N Hem with a clear signal for a +ve pressure anom over the pole -AO etc

If this comes off it could be good news for winter lovers.

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If this comes off it could be good news for winter lovers.

Unless, like almost all LRFs, it changes next week?

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Just been looking at the MEI and QBO data for the coming weekend and the QBO will peak anytime between now and November (we had the joint strongest -QBO value for August).

The MEI value surprisingly dropped and cold water has developed near the American coast at the surface, this may simply be a short term thing or result in neutrality for winter.

1984 looks the strongest analogue overall.

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Just been looking at the MEI and QBO data for the coming weekend and the QBO will peak anytime between now and November (we had the joint strongest -QBO value for August).

The MEI value surprisingly dropped and cold water has developed near the American coast at the surface, this may simply be a short term thing or result in neutrality for winter.

1984 looks the strongest analogue overall.

How close were the analogues last winter sb? Did any years come close to the winter recorded?

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How close were the analogues last winter sb? Did any years come close to the winter recorded?

2008: -0.7

1999: -1.2

1995: -0.6

1985: -0.2

1970: -1.5

1967:

These were the analogues i used last winter (ignore the value next to them) - don't have the CET data on hand so see if any were close.

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2008: -0.7

1999: -1.2

1995: -0.6

1985: -0.2

1970: -1.5

1967:

These were the analogues i used last winter (ignore the value next to them) - don't have the CET data on hand so see if any were close.

I can't believe you spent so long working out the analogue years and then didn't check after the event!!

http://www.metoffice.gov.uk/hadobs/hadcet/ssn_HadCET_mean.txt

Above are the seasonal CET figures since 1659. I have put them next to your years to see if there is any pattern.

2008: 5.6ºC

1999: 5.4ºC

1995: 5.9ºC

1985: 2.7ºC

1970: 3.3ºC

1967: 5.1ºC

Average: 4.7ºC

and 2012: 5.1ºC

So, overall when averaged out the analogues are fairly close to the actual, but there are probably statistically significant differences in those years. Interestingly, 1967 was bang on.

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