Possible Clues:

• One's going to court around Circle Line
• Weather graphic
• Thus I exclude pressure all the same along there
• Thus I forbid pressure, all the same, along the line
• Meteorological line joining points of equal pressure
• Weathermap line
• It connects similar pressure points
• I fly around British feature on map
• (Map) line of constant pressure
• One's going to pub around the Circle Line