Verdict?

At least it gave us something to talk about in the "build up"

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Verdict?

 

Bin it.

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Very good result for E and NE USA but didn't work out for NW Europe at all well

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Put it this way I don't think it will be discussed with as much enthusiasm this October.

It will probably be plus figure in October and we will be buried up to our waist in snow the following Winter, putting a further nail in OPI coffin

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Verdict?

Little correlation with what happened, unfortunately:

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao_index_ensm.shtml

One swallow doesn't a summer make, but the first real test of the OPI hasn't shown it in a good light...

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hmm....

It certainly hasnt been a mild winter, lots of snow for some places, and I would argue a large portion of the UK has seen snow falling, with another large amount seeing it settle.

This to me in my eyes despite being fairly benign for MBY, has been a more wintry than average winter (but only slightly) I think the OPI has probably delivered a signal.. but not a concrete answer. I think people are unfairly expecting snow on the ground for weeks on end.. that kind of scenario is a 1 in 20 yr event probably. This isnt reflective of the typical UK Winter.

The winter of 2014/15 should be considered a classic - similar to how the summer of 2014 was seen.

I think the OPI should be considered as a good indicator in the winter forecasts in future.

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Little correlation with what happened, unfortunately:

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao_index_ensm.shtml

One swallow doesn't a summer make, but the first real test of the OPI hasn't shown it in a good light...

 Very good summary IMO. 

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A different angle this, but how often does the AO climb all the way up to +6 as shown for a week's time...? Seems pretty extreme 

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The mean AO index figure for winter 2014/15 was +0.85. This is one of the highest figures in the historic series going back to 1950. So the OPI was a very poor predictor of the AO index this year.

Highest DJF AO index mean figures

1988/89  2.69 
1992/93  1.77
1989/90  1.25
1999/00  1.13
1991/92  1.09
1972/73  1.09
2006/07  1.00
1975/76  0.99
2007/08  0.86
2014/15  0.85

So winter 2014/15 saw the 10th highest AO index in the last 65 years

A different angle this, but how often does the AO climb all the way up to +6 as shown for a week's time...? Seems pretty extreme 

The AO index exceeded +5 yesterday (7 March). http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao_index.html

Prior to yesterday the AO index had only exceeded +5 on 14 days since 1950. So this is indeed very unusual. The AO index has never reached 6 so it will be interesting to see what happens over the next few days. All previous instances of a >+5 index have been in Dec, Jan or Feb.

Highest daily AO figures on record