Philip Eden wrote:

For those who like to view Britain's weather through the flawed
prism of the NAO index, that index during March was negative,
very very negative, more negative even than any calendar month
since Feb 1986.

And yet there was much mobility over the Atlantic Ocean and
western Europe south of latitude 50 degN, and this mobility
penetrated across the whole of the British Isles during the second
week of March and again from the 24th onwards, resulting in an
outstandingly wet month in many parts of the UK ... exactly
what one is supposed to get with a -ve NAOi month, right?

I can never remember what the southern oscillation is supposed to
produce. And I rather think there are 3 or 4 phases to it rather than
the simplified el nino/la nina approach.\/

Charts: http://www.climate-uk.com/monpre/0603.htm
The Monthly Review at: http://www.climate-uk.com/monthly/0603.htm
Graphs: http://www.climate-uk.com/graphs/0603.htm and http://www.climate-uk.com/graphs/200603.htm

The
Not The Long Range Forecast: http://www.climate-uk.com/page4.html

The mean sea-level chart shows that the Icelandic Low is displaced far to the
southwest of its normal position, with the main centre 999mbar just ESE of
Newfoundland but a marked trough extends ENE-wards across the Atlantic and
the British Isles to the central North Sea.

A weak Azores High (1018mbar) is displaced to Madeira, while abnormally
high pressure (1030+ mbar) sits over northern Greenland.

The mean flow is SW-ly over England, Wales, both parts of
Ireland, and southern Scotland, but E-ly over north Scotland.

The main features of the sea-level pressure anomaly field are the big departures
over Greenland (+ve) and mid-Atlantic (-ve) and the extensive zone of anomalous
E-ly gradient between.

The main centres a
+13mbar over Greenland
-12mbar between the Azores and Newfoundland
-7mbar over Romania

Over the British Isles pressure anomaly ranges from zero over
Shetland and -8mbar at Valentia.

The anomalous flow is E-ly over Scotland, Northern Ireland
and northern England, but S-ly over the bulk of England and
Wales.

CET (after Manley) 5.0°C (-1.4 degC wrt 1971-2000)
CET (after Hadley) 4.95°C (-1.45 degC)

and by this measure it was the coldest March since 1996, /\
although only marginally colder than March 2001.

E&W Rain:
87.1mm (119% of 1971-2000 mean) making it the first month with above-average
rainfall since November, and also the wettest March since 2001.

E&W Sunshine: 106.3 hr (94% of 1971-2000 mean)
It was outstandingly dull after the first six days which were exceptionally sunny.

CScotT: 4.1°C (-1.7 degC)
ScotRain: 98.8mm (141%)
ScotSun: 83.6 hr ( 80%)

NIT: 5.7°C (-1.1 degC)
NI Rain: 91.8mm (147%)
NI Sun: 101.2 hr ( 91%)

Rainfall totals ranged from 403.0mm at Capel Curig (Snowdonia) to
20.3mm at Southend (Essex)

Percentages ranged from 277 at West Freugh (Galloway) to 49 at Hurn (Dorset).

Sunshine totals ranged from 156.0hr at St Helier (Jersey) -a CS recorder
- to 56.5hr at Kinloss (Moray) -a KZ sensor.

Percentages ranged from 109 at Cromer (Norfolk) to 48 at Kinloss.

(c) Philip Eden

The NAO index is useful *if* you know how to use it.

There is a misconception that a negative NAO always means a blocked pattern
- it doesn't.That can be seen clearly in the mathematics as a negative NAO can
arise from a shallower than normal Icelandic low and a less intense Azores high.

Even a high over Iceland all month can still mean lows/fronts crossing the UK but
further south than normal.

The NAO is really only useful for climatologists and possibly for
seasonal prediction -not for the prediction of individual months and weeks.

It is an atmospheric mode of variability ie part of the spectrum that causes
variability in the atmospheric flow over the North Atlantic, to understand it
properly one needs to go into wave theory, which is involved.

Once again we see people dabbling in and using something they don't properly
understand (I don't mean you BTW Philip). And you can't understand it properly
without many weeks/months of training in mathematics and meteorology.

Actually you don't need much more than schoolboy physics to know that
there is no way a wave can travel unaided through a gas. Some people
still believe that the air around a storm an fill with electricity in
order to produce lightning.

(Sometime after the first serious research showed it to be too unlikley
to be so.)

Once a portion of the atmosphere has been compressed or whatever, it
would take a force of orders of magnitude greater than that first
cause, to pass it on.

Without risking further ire from ne'er do anythings like ***:
The oceanic oscillations seem to rely on the ice cover of the various
seas in them -or in the snow cover of the land-masses surrounding
others. Maybe both.

(Probably both.)

Whether or not this is a cyclical thing that is regulated by the
distortion of the planet's orbit or merely by poor land management or
(again) both, remains to be seen.

It is stupid to actively persuade others to follow know-nothings into
ignoring other paths. For there is no other "wave" that can act over a
series of years.

Is there?