Cwmbach Climate

I promise this will be the one and only photo of my garden, and locality (please remove it if it bothers you, Dave) but I find the subject of local climate and its effect on moth catches intriguing, so to continue the debate with Adam:
As you can see, my garden is fairly sheltered. It is on a S.West facing hillside, which means we tend to catch the prevailing westerlies, but are spared the worst of the North and East winds. The house, which is close behind me, forms an effective barrier to cold air flowing down slope from the hill and tends to form a frost pocket, which only really becomes an issue in the winter (GMS) and spring. The horizon visible is at about 900ft and isn't actually the top of the hill.After a false flat, the hill carries on up to 1200ft.