Why do northwestern and southwestern England receive more rain than some eastern regions?

The variation in rainfall across England is primarily driven by the country's position in relation to atmospheric circulation patterns and the movement of moisture-laden air masses from the west.1

Rain-producing systems typically arrive from a westerly direction, bringing maritime air from the Atlantic Ocean. As these air masses move across the country, the western regions—specifically the northwest and southwest—are the first to encounter this moisture, leading to higher annual precipitation. In contrast, eastern regions, such as Norfolk, Suffolk, and the Thames estuary, are sheltered from the full impact of these westerly systems. Consequently, these eastern areas receive significantly less rainfall, often averaging less than 30 inches (750 mm) annually, and may frequently experience drought conditions.12