The present exceptionally weak phase of the Arctic
Oscillation appears to have been the dominant influence
on the synoptic characteristics of the summer quarter
(J,J,A) of 2009.

Mean sea-level pressure and anomaly charts can be found at

http://www.climate-uk.com/monpre/09QQ.htm

The mean sea-level pressure field shows the Icelandic
Low displaced well south of its normal location at
56N 20W, central pressure 1009mbar. The Azores
High is at normal intensity (1022mbar) slightly SW of
its normal position. The net effect is to transfer and squeeze
the strongest surface flow across the Atlantic to between
latitudes 40 and 50degN instead of its normal position
between lats 45 and 60degN. There is an anomalous
area of high pressure, 1020mbar, centred over Greenland.
The mean surface flow over the British Isles is SW-ly
instead of the more usual W-ly.

The mean anomaly field is dominated by two centres:
-7mbar off SW Ireland (at 51N 19W)
+8mbar over central/NE Greenland
The anomalous flow over the British Isles is SSW-ly over
England, Wales and Ireland, and SSE-ly over Scotland.
Mean anomaly ranges from -1.5mbar in Sussex and Kent
to -5mbar on the west coast of Ireland. The 'southerliness'
index has only been exceeded in four summers in 137
years of records: in 1947, 1950, 1994 and 2003.

CET (Manley): 15.93°C (+0.3 degC wrt 1971-2000)
E&W Rainfall: 252.3mm (128% wrt 1971-2000)
E&W Sunshine: 589.0h (100% wrt 1971-2000)

CScotT: 14.76°C (+0.7 degC)
Scot Rainfall: 300.2mm (150%)
Scot Sunshine: 542.6h (114%)

NIT: 14.78°C (+0.5 degC)
NI Rainfall: 307.8mm (161%)
NI Sunshine: 567.1h (117%)

(c) Philip Eden