I know Philip Eden has already mentioned it, but why and what has
caused the the Greenland High to be so dominant over the past 3
months?

http://www.wetterzentrale.de/pics/bracka.html

If only this was Winter, we may be in for some interesting cold
weather.

However in Summer it is just a spoiler.

If this continues, people may stop talking about global warming and
start talking about localised cooling!