In Depth Model Discussion, Analysis and Summaries

[chionomaniac]

I don't think that a weak El Nino would be a bad thing for winter

[summer blizzard]

MEI is already at +0.9.

[chionomaniac]

Would say August is now again looking pretty doubtful as the angular momentum seems to have stalled a bit by this link:

http://www.esrl.noaa...m.sig.90day.gif

And solar cycles are pretty low according to these links:

http://solarham.net/

http://spaceweather.com/

Which to me is a cause for concern with the August sypnotics as more sunspots means more radiation to get the jet stream in a more desirable position.

All looking very tentative and liable to change methinks.

By what process does that work and instantly Ledders?

[Methuselah]

Would say August is now again looking pretty doubtful as the angular momentum seems to have stalled a bit by this link:

http://www.esrl.noaa...m.sig.90day.gif

And solar cycles are pretty low according to these links:

http://solarham.net/

http://spaceweather.com/

Which to me is a cause for concern with the August sypnotics as more sunspots means more radiation to get the jet stream in a more desirable position.

All looking very tentative and liable to change methinks.

How do you arrive at that conclusion, ledders? Does it have any validity?

[Radiating Dendrite]

I thought that the idea was that a more active sun promoted a more northerly tracking jet, which should be better for summer.

Anyway, it is not an instant feedback mechanism.

[summer blizzard]

Think I am relying on the Piers Corbyn and James Madden theory too much. I do agree a little bit what they say even if it isn't completely the case at times. You guys are correct and maybe I should decide things for myself. Very pleasing that the MEI is in weak el niño territory.

I personally believe that sunspots are a poor measurement of overall solar activity as they vary in strength quite a lot and as such i prefer the solar flux data measurement (monthly values below)...

http://www.esrl.noaa.gov/psd/data/correlation/solar.data

This shows that solar activity as a whole is still historically low for this stage in the solar cycle and that the peak of this cycle so far actually occured in Novemeber 2011, so solar activity may actually have already peaked in terms of energy output.

[Greybird]

My understanding is that it is the strength of emitted UV that influences the jetstream.

Thus a high level of UV could be present even though overall energy out put is low and the reverse, low UV levels coupled with high overall energy output.

edit: http://www.bbc.co.uk/news/science-environment-15199065

Edited July 27, 2012 by Greybird

[Polar Maritime]

Feb 2013 is the expected peak for this cycle.

Edited July 28, 2012 by Polar Maritime

[cooling climate]

Sorry I thought this was the technical model discussion thread.

Some of the posts in here are a joke.

[johnholmes]

Sorry I thought this was the technical model discussion thread.

Some of the posts in here are a joke.

was that comment at all necessary?

It saddens me that you have made this comment-yes its a technical thread but it is encouraging when folk try to add something even if their knowledge is less than others. A lyou have to do if someone annoys you is set them to ignore.

[johnholmes]

Know I have enjoyed contributing to this site and posting in this section but would like it if my membership was closed as it appears that I am struggling a bit and don't want to make an idiot of myself on a site that is beyond me. If people want to follow me on Twitter my username is @pjl20101. Good luck guys.

ledders, there are times when your posts have irritated me, capitals etc, but I do hope you will reconsider, this forum is for all, those with a deep knowledge of meteorology and those that do not have that depth of knowledge.

I have been a member for 8 years or so. One of the things I have found encouraging is the number of folk who arrive on here with not much meteorological knowledge but who obviously have learnt a lot and go on to make a real contribution to the site.

think again.

[samadamsuk]

here here John. Ledders come back! Being humble and open about a lack of knowledge is a commendable thing - some people are too proud or egotistical to do this, and they wont progress half as fast. It doesnt mean you cant make valuable contributions to a discussion, and certainly doesnt mean the vast majority dont want you to be part of it!

Sorry mods - delete this if needs be

Sam

[cooling climate]

Ledders John is right I should not of made that post. It was abrupt and

unnecessary and for that I apologize.

[cooling climate]

1948 -4.44 -5.78 -7.31 -6.70 -5.57 -4.73 -5.51 -7.22 -7.24 -6.07 -6.28 -8.18

1949 -9.77 -11.80 -11.72 -10.69 -9.34 -9.43 -9.07 -9.08 -8.32 -7.01 -6.43 -7.24

1950 -8.99 -11.37 -10.63 -8.19 -6.09 -6.61 -7.11 -6.51 -3.82 -2.39 -2.18 -3.31

1951 -6.01 -5.32 -1.93 0.91 2.26 -0.30 -2.70 -5.31 -5.92 -4.59 -3.65 -3.98

1952 -6.80 -7.71 -6.99 -5.68 -4.76 -6.00 -7.60 -8.15 -5.73 -2.96 -0.51 -1.65

1953 -2.94 -2.68 -1.22 1.30 2.69 1.86 0.10 -1.21 -1.28 -0.39 -0.59 -2.18

1954 -5.05 -6.88 -7.98 -9.01 -11.38 -12.72 -13.40 -14.53 -12.83 -10.35 -9.99 -9.56

1955 -5.82 -1.71 1.37 4.40 6.58 6.73 5.99 7.20 8.16 9.02 7.63 3.82

1956 -1.01 -3.23 -2.01 -2.01 -6.16 -11.02 -13.04 -15.17 -14.67 -14.90 -16.96 -15.02

1957 -13.05 -11.89 -6.68 -2.01 1.80 3.21 4.05 6.30 8.36 10.46 10.11 7.35

1958 5.25 4.10 4.27 1.98 -4.71 -10.60 -13.91 -15.59 -15.93 -16.39 -16.91 -18.96

1959 -20.06 -17.24 -14.02 -9.27 -5.91 -2.30 3.15 7.07 10.09 11.69 10.71 8.30

1960 4.79 3.39 -0.04 -1.08 -3.91 -8.98 -13.86 -16.04 -16.01 -15.62 -14.42 -11.36

1961 -5.47 -0.62 0.54 2.82 6.88 7.96 6.69 5.60 6.02 7.59 8.74 6.25

1962 2.84 3.68 5.26 2.04 -3.64 -11.42 -15.49 -15.00 -15.19 -15.33 -15.40 -15.16

1963 -17.35 -16.68 -19.93 -21.52 -24.18 -20.08 -9.27 -1.35 3.52 7.54 8.87 5.48

1964 3.94 5.26 5.46 5.94 6.32 2.23 -0.56 -0.57 -0.67 0.42 0.71 0.04

1965 -1.03 -2.26 -1.98 -3.44 -7.10 -12.01 -16.00 -18.19 -20.03 -20.13 -19.74 -21.27

1966 -21.90 -17.14 -11.07 -2.33 2.16 5.42 7.47 7.63 9.23 11.00 11.74 13.26

1967 11.03 10.49 10.94 10.13 5.79 -0.58 -5.65 -6.76 -6.06 -4.82 -6.05 -7.27

1968 -8.38 -10.21 -9.11 -12.25 -14.39 -19.27 -21.00 -21.82 -17.45 -14.58 -13.11 -11.36

1969 -8.58 -4.43 -1.50 3.98 8.18 9.35 9.08 9.78 9.74 9.75 7.34 5.00

1970 0.30 -1.41 -4.63 -7.25 -12.21 -16.25 -18.62 -21.38 -21.67 -22.12 -22.48 -17.39

1971 -10.67 -3.67 0.91 3.75 6.77 8.28 8.88 8.34 8.95 8.48 8.47 9.10

1972 8.20 7.95 7.35 6.22 -2.59 -10.70 -15.45 -19.28 -20.40 -21.17 -20.49 -16.78

1973 -4.40 0.08 3.40 6.28 8.12 8.63 6.94 5.86 5.51 5.20 4.92 2.31

1974 -0.91 -1.31 -1.08 -1.92 -7.58 -13.86 -19.58 -23.14 -23.52 -23.12 -22.48 -22.57

1975 -16.70 -15.39 -13.04 -5.12 1.18 4.47 7.41 9.06 10.25 10.65 11.27 10.95

1976 9.22 8.92 9.70 11.53 10.04 2.78 -1.90 -4.89 -6.19 -8.23 -8.89 -11.85

1977 -14.44 -14.90 -17.61 -14.93 -17.14 -21.33 -18.17 -11.24 -5.09 -1.81 -0.26 1.69

1978 3.21 6.07 9.34 12.98 12.23 8.36 6.02 5.84 5.91 6.22 4.04 1.46

1979 1.86 4.12 0.89 -3.57 -12.90 -19.60 -21.27 -22.24 -22.70 -23.32 -22.20 -16.99

1980 -10.11 -5.65 -2.90 2.31 6.24 7.33 8.74 9.61 12.67 13.10 12.15 9.73

1981 8.51 6.72 7.51 8.28 3.01 -3.49 -5.22 -8.24 -8.59 -9.53 -9.62 -12.31

1982 -12.52 -14.71 -16.67 -15.55 -15.26 -15.94 -8.95 -1.58 4.21 8.27 9.51 10.35

1983 10.85 11.40 12.17 13.81 11.93 3.12 -3.38 -6.53 -7.75 -10.12 -10.29 -11.42

1984 -10.65 -11.34 -12.98 -14.58 -15.05 -17.97 -25.39 -27.90 -25.44 -21.59 -13.19 -8.16

1985 -0.37 4.21 6.30 11.11 13.57 14.04 11.10 11.08 11.72 11.84 11.45 9.51

1986 8.74 10.15 11.96 9.11 3.56 -2.15 -5.25 -9.60 -10.21 -9.60 -8.01 -10.51

1987 -9.93 -11.37 -14.23 -16.20 -20.05 -21.47 -13.96 -0.60 5.88 9.35 9.23 8.41

1988 7.81 6.17 5.86 6.59 5.46 0.42 -3.96 -2.58 -2.29 -1.53 -0.84 -2.42

1989 -2.87 -3.56 -1.63 -1.93 -5.46 -9.38 -13.86 -16.98 -18.83 -21.30 -19.01 -13.54

1990 -8.71 -6.74 0.95 5.72 11.46 12.90 12.54 12.63 13.21 12.39 11.55 10.68

1991 8.71 8.44 9.00 10.69 3.82 -3.34 -10.36 -14.69 -13.96 -12.21 -12.27 -12.68

1992 -13.96 -14.33 -16.84 -17.79 -15.96 -15.34 -12.05 -4.75 1.30 3.94 6.33 8.19

1993 9.63 10.81 11.36 12.60 13.56 6.55 0.38 -1.20 -1.14 -4.04 -5.76 -6.00

1994 -7.64 -9.84 -11.29 -14.71 -18.03 -23.09 -28.65 -27.02 -19.07 -10.29 -0.30 5.93

1995 8.38 8.01 8.79 11.79 14.92 15.62 11.74 9.53 6.98 3.43 -0.77 -4.57

1996 -5.79 -6.90 -9.92 -11.08 -14.88 -17.03 -23.93 -25.85 -26.02 -23.40 -18.08 -9.86

1997 -3.57 1.94 4.77 9.74 12.37 14.50 14.85 11.69 11.64 9.91 5.74 0.78

1998 -0.85 -2.96 -4.92 -7.82 -14.08 -18.57 -22.97 -24.70 -22.12 -18.77 -12.22 -3.96

1999 3.09 5.84 8.59 13.51 15.56 15.23 14.11 11.91 11.18 10.62 6.01 6.43

2000 4.85 4.20 5.51 3.98 -0.99 -7.83 -13.13 -15.31 -15.52 -14.04 -15.07 -14.56

2001 -15.69 -15.53 -15.99 -17.73 -20.99 -23.31 -24.45 -21.67 -14.29 -10.81 -3.88 1.48

2002 4.64 8.00 9.32 14.03 14.16 13.26 10.05 10.60 8.90 7.66 4.46 -0.50

2003 -1.39 -1.43 -3.30 -8.56 -13.63 -17.71 -22.99 -24.64 -22.51 -20.34 -17.86 -11.38

2004 -4.84 2.61 5.45 10.46 12.97 11.75 9.96 8.74 7.29 8.00 4.35 2.45

2005 -0.69 -0.96 -0.33 -6.64 -15.09 -20.59 -24.20 -25.87 -27.80 -28.76 -29.55 -25.04

2006 -18.83 -11.24 -0.38 5.00 10.36 11.47 10.75 9.10 10.20 10.86 10.10 6.21

2007 2.61 2.43 1.24 -5.18 -14.06 -21.33 -24.92 -27.41 -28.13 -29.05 -27.61 -19.48

2008 -12.42 -4.70 2.19 6.43 11.53 13.45 13.27 11.63 11.60 11.05 9.13 10.46

2009 10.71 12.33 11.44 9.11 1.56 -5.47 -12.21 -14.45 -13.81 -11.69 -13.83 -15.57

2010 -16.02 -16.98 -19.68 -23.57 -26.28 -25.05 -9.84 1.45 6.58 10.83 12.16 10.97

2011 9.18 10.05 10.44 10.71 10.02 3.90 0.44 -0.49 -2.30 -3.05 -9.09 -16.25

2012 -16.09 -15.26 -16.75 -17.63 -22.05 -25.90 -27.83 -999.00 -999.00 -999.00 -999.00 -999.00

-999.0

QBO

Calculated at NOAA/ESRL PSD

30mb zonal wind at the equator, zonal average

30mb zonal winds at the equator for July is -27.83 down again from

Junes reading so it appears we will be in a negative or easterly phase

QBO state into the first half of winter. In the lower stratosphere.

[legritter]

although i have not posted in this thread i find it very educational and interesting .i will read up on some of the technical aspects and try and put some post together .i have always felt that this branch of meteorology once researched and studied ,of course over a period of time with a professional loging of information will add alot of good information to the pot . cheers

[summer blizzard]

http://www.cpc.ncep.noaa.gov/data/indices/qbo.u30.index

Whilst the original data does indeed show a small increase, the standardised data shows a small decrease indicating the -QBO peaked in June.

Additionally the collapse to neutral is normally very quick and as such a neutral to +QBO is more likely.

[cooling climate]

http://www.cpc.ncep....s/qbo.u30.index

Whilst the original data does indeed show a small increase, the standardised data shows a small decrease indicating the -QBO peaked in June.

Additionally the collapse to neutral is normally very quick and as such a neutral to +QBO is more likely.

In the upper stratosphere yes but not in the lower stratosphere.

[summer blizzard]

A potentially unstable outlook in my opinion which could easily swing to anonomously warm to cold and back again.

Looking at the USA we see a classic El Nino pattern with a +PNA and pretty amplified Jet Stream, the result of which is a -NAO (especially during summer when the thermal gradient is low). Now the unstable pattern i refer to comes into the fray now because on the one hand such a scenario can encourage pressure to build over Greenland and a subsequent Atlantic Ridge/northerly however on the other hand the scenario can also result in a slow moving trough near the Azores which corresponds to todays scenario with a ridge over the UK/Scandinavia and at this time of year that is a warm outlook.

Given the -PDO and -QBO i must lean towards the Atlantic Ridge scenario however if GLAMM can increase measureably then we could see the later scenario persist.

On the whole however i would suggest the outlook is drier and probably sunnier than average, it is the temperature which is up in the air.

[SMU]

Chono or Stewart

can you post the link to the NCEP reanalysis charts & the link to the 60 N Zonal wind anomaly

many thanks

Steve

[chionomaniac]

Chono or Stewart

can you post the link to the NCEP reanalysis charts & the link to the 60 N Zonal wind anomaly

many thanks

Steve

Hi Steve,

Reanalysis can be found from this main page:

http://www.esrl.noaa.gov/psd/data/reanalysis/reanalysis.shtml

Best page for actual zonal wind throughout the year can be found from here:

http://acdb-ext.gsfc.nasa.gov/Data_services/met/ann_data.html

or here for charts:

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/

I have plenty of other similar links if these are not the right ones.

c

[Glacier Point]

Extended range ensemble means are suggesting a very amplified long wave pattern to develop across the Northern Hemisphere in the next 2-3 weeks. Are they right in doing so ? Roughly I think they are although I suspect the placement of the trough in our locale is going to be the hardest part to nail and thinking would be that they are under-estimating anomalous ridging over Europe.

Over the last 5-10 days, frictional torques have been negative, suggestive of attempts for the atmosphere to add westerlies to the global circulation.

There are now indications that these torques are starting to bear fruit, with tendency in angular momentum rising and likely to rise sharply in the next week as mountain torques (especially North American) begin to respond to this forcing and we get a wave breaking from the Pacific associated with forecast development of tropical system Sanba. Notably, the Southern Oscillation Index has started to drift back to El Nino status after a bit of a lull (potential for more tropical storms to develop across the Northern Hemisphere) and MJO forecasts are starting to drift towards a phase 8 destination, again El Nino type activity.

This will drive the GWO into high amplitude phase 4 which favours a very meridional wave pattern, ridges over Alaska and Siberia, deep trough over eastern half of North America. Composite below.

Notice however the residual heights over Europe which will deflect any northerly plunge into Europe further east and restrict it to Scandinavia. Upper level polar westerlies have just started to develop, so there are two factors calling for some moderation of the trough signal put up by the models at present. There is also a weak troughing signal underneath the mid Atlantic ridge which complicates things, trapping tropical systems underneath the ridge causing model headache.

Moving forward, frictional and mountain torques will want to cycle back and remove westerlies in the absence of a strong coupled atmosphere - ENSO signal. This will shift the GWO back towards a low amplitude phase 2 or 3. Composites below:

Both maintain weakish ridges close to the UK or just north and west of the UK.

So not much weight for anything deeply unsettled, more cool and showery with longer dry spells looks the call at present.

Edited September 13, 2012 by Glacier Point

[summer blizzard]

Interesting, any early thoughts on winter this year GP?

[BLAST FROM THE PAST]

Interesting, any early thoughts on winter this year GP?

IMO its about the jet and I believe more south than normal and meridional. I see no reason for any real change. I don't think we'll see a cold unfriendly PV dominating. BFTP

[chionomaniac]

IMO its about the jet and I believe more south than normal and meridional. I see no reason for any real change. I don't think we'll see a cold unfriendly PV dominating. BFTP

Is that a specific forecast for this winter Fred, or upcoming winters in general?

[Cal]

IMO its about the jet and I believe more south than normal and meridional. I see no reason for any real change. I don't think we'll see a cold unfriendly PV dominating. BFTP

Ah, is there anything in this theory to back it up? After all this is the Tech Model thread....