Karen measured her height as 59 inches that is 27 inches more than half her older sister height how tall is her older sister

To find out how tall Karen's older sister is, we need to subtract 27 inches from Karen's height.

Half of Karen's height is 59 inches / 2 = <<59/2=29.5>>29.5 inches.
So Karen's older sister is 29.5 inches - 27 inches = <<29.5-27=2.5>>2.5 inches tall. Answer: \boxed{2.5}.