It's an obvious point, but noise does get carried by the wind. At Brands Hatch circuit the prevailing wind direction is West to East, so those villages that lie East of the circuit will tend to notice circuit activity more often. 

Winds are described in terms of where they come from, so as examples: 

• A Northerly wind will blow towards the South
• An Easterly wind will blow towards the West
• A Westerly wind will blow towards the East
• A Southerly wind will blow towards the North 

Humidity also effects how far noise is carried. It will travel shorter distances on dry, warm summer days, and longer distances in mist and fog. On a foggy day with a breeze, noise will travel the furthest. 

For up to date information on current weather conditions in the Brands Hatch area, click here to visit the BBC's weather site.