High pressure ans showers

[lorrimor]

Hi Guys, 

 

I wonder if you could help, this might seem a pretty basic stupid question but its something that I just cant seem to work out!

 

Using this chart as an example there is high pressure over the south of country yet the rainfall chart is showing the high pressure bringing showers in.

 

Why is this as usually you would associate high pressure with dry weather.  Is it because the air picks up moisture as it travels over water which then causes showers when the air passes over land because of the temperature difference between the sea and land?

 

Thanks in advance for any help:)

 

[Andy Bown]

Those could be a few reasons and also, what that chart won't show, is if there's a weak front or trough amongst the HIGH.