In early September, several longer range models were suggesting a window of high pressure moving in from mid-September onward. Now that mid-September is upon us, short-term forecast models indicate that this period will not be settled. Quite the opposite actually - a continued mixed regime with several windows of rain,

Throughout today, a frontal boundary will move southward across the British Isles, bringing a band of rain with it, which could be quite heavy in places. There will however be a notable rain shadow effect, which the chart below exemplifies quite well (chart valid for midnight into Sunday): This is a